ALBERT

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 118〈/p〉 〈p〉Author(s): Payam Mokhtari, Mehrorang Ghaedi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, facile and green method for synthesis of imprinted material was introduced which subsequently applied for efficient delivery of Riboflavin (vitamin B〈sub〉2〈/sub〉). Characterization of the prepared polymer was carried out by the Fourier Transform Infrared (FT-IR) spectroscopy and Scanning Electron Microscopy (SEM). The weight ratio of functional monomer to template over 5–20 W/W% was evaluated in order to find the best loading condition and subsequent release into synthetic biomimetic media namely simulated body fluid (SBF) and media including 1% NaCl solution, simulated gastric fluid (SGF) solution at pH 1.5 and the solution of 1% W/W Na〈sub〉2〈/sub〉SO〈sub〉4〈/sub〉. Under optimized condition, the highest value of released riboflavin was achieved at 1:20 ratio of riboflavin to polymer in NaCl (55.07%) media which providing that the body requirement about 5 days of this vitamin between minimum effective concentration (MEC) and maximum safe concentration (MSC) of Riboflavin in short release time (45 min). Moreover, the experimental data were fitted to Higuchi model in order to calculate Higuchi solubility constant.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001430571930518X-ga1.jpg" width="367" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 118〈/p〉 〈p〉Author(s): Marcin Mackiewicz, Jan Romanski, Pamela Krug, Maciej Mazur, Zbigniew Stojek, Marcin Karbarz〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nanogels are promising carriers for drug delivery, especially when they degrade under conditions typical for cancer cells to release a drug. By using the precipitation polymerization we synthesized a biocompatible and degradable nanogel based on poly(ethylene glycol) methyl ether methacrylate (OEGMA) and di(ethylene glycol) methyl ether methacrylate (MEO〈sub〉2〈/sub〉MA) cross-linked with a redox-sensitive linker, 〈em〉N,N′〈/em〉-bis(methacryloyl)cystine – (mBISS). The application of appropriate proportions of monomers during the nanogel synthesis allowed us to set its volume-phase-transition temperature to the body temperature while the aggregation of the nanogel in physiological conditions was eliminated. The presence of carboxylic groups in mBISS made the nanogel sensitive to pH, gave it stability under conditions of high ionic strength and allowed it to bind the anticancer drug – doxorubicin (DOX). The degradation of nanogel was examined by using electron microscopies. In the presence of a high concentration of glutathione (a reducing agent for the -S-S- bridges) which is the case for most cancer cells, the spherical shape of the nanogel and correspondingly its structure were destroyed. The obtained profiles for the release of DOX from the nanogel revealed that the smallest amount of DOX was released from the nanogel at pH 7.4, while under conditions present in most cancer cells, this is at pH 5.0 and c〈sub〉GSH〈/sub〉 = 40 mM, the highest cumulative release of DOX was observed. The DOX loaded nanogels were cytotoxic against MCF-27 and HT-29 cancer cells similarly to DOX alone. The unloaded gel nanoparticles did not inhibit proliferation of the cells.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719306299-ga1.jpg" width="498" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 118〈/p〉 〈p〉Author(s): Andrea Dodero, Lara Pianella, Silvia Vicini, Marina Alloisio, Massimo Ottonelli, Maila Castellano〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Alginate-based hydrogels can be obtained by the simple addition of bivalent ions to aqueous polysaccharide solutions without the use of toxic chemicals; however, the hydrogels prepared by this way result inhomogeneous and irreproducible due to the extremely fast crosslinking reaction. To overcome such limitations, in the present work a novel preparation approach is proposed and optimized; the method is based on the use of agar moulds rich of bivalent ions as diffusing system to modulate the release of Ca〈sup〉2+〈/sup〉, Sr〈sup〉2+〈/sup〉, and Ba〈sup〉2+〈/sup〉 cations in order to guarantee a better control of the crosslinking process. A full factorial experimental design was applied to assess the effects and the mutual interactions of three selected parameters (sodium alginate concentration, crosslinking agent concentration within the agar moulds, crosslinking time) on the gelation process. The swelling and mechanical properties of the prepared hydrogels were investigated both in deionized water and in a saline environment; furthermore, the hydrogels were characterized by means of thermogravimetric analysis and field-emission scanning electron microscopy. The obtained results demonstrated that both the experimental variables and the environmental conditions have a significant influence on the structure and the performances of the resulting hydrogels. In particular, the use of high polymer concentration and crosslinking agent amount leads to strong hydrogels corresponding to a superior crosslinking degree; more in detail, Ba〈sup〉2+〈/sup〉 ions show a great affinity for alginate leading to the hydrogels with the highest mechanical properties. Moreover, the ion-exchange occurring in saline environment seems to strongly reduce the effective crosslinking degree of alginate hydrogels with a consequential loss of mechanical properties and stability. The collected data were finally elaborated through statistical analysis combined with response surface methodology to develop theoretical models successfully able to correlate the crosslinking degree to the experimental conditions, thus opening the way of designing and fabricating alginate-based hydrogels with tailored morphology and mechanical properties.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719306986-ga1.jpg" width="370" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Maria Toplishek, Ema Žagar, David Pahovnik〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A synthetic approach to the dicyano-substituted ε-caprolactone was developed. It consists of a cyclohexanone ring assembly through the Diels-Alder reaction followed by the Baeyer-Villiger oxidation. Ring-opening polymerization of the synthesized monomer, catalyzed by the aluminum alkoxides, was performed in a well-controlled manner and provided the nitrile-polyester homopolymers of various molar masses. The synthesized nitrilePCL homopolymers are amorphous with a significantly higher glass transition temperature (66–69 °C) compared to the unsubstituted PCL. The dicyano-substituted ε-caprolactone monomer was copolymerized with the unsubstituted ε-caprolactone to prepare the statistical and block copolymers. Furthermore, the cyano groups of the nitrilePCL homopolymers were transformed into the amide groups by post-polymerization modification under anhydrous conditions using the Wilkinson’s catalyst. The resulting amide-functionalized polyesters are water-soluble when the degree of transformation is higher than 80%.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001430571931225X-ga1.jpg" width="339" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Ander Reizabal, José Manuel Laza, José María Cuevas, Luis Manuel León, José Luis Vilas-Vilela〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Different polycyclooctene (PCO) and linear low-density polyethylene (LLDPE) blends were crosslinked with 2 wt% of dicumyl peroxide (DCP) in order to obtain thermoresponsive shape memory materials with transition temperatures close to bodýs external temperature. These polymeric blends allow tailoring properties by the synergic combination of shape-memory capability of PCO and effective mechanical and processing performance of polyethylene. Thermal stability of these materials was characterised by thermogravimetric analysis (TGA), whereas mechanical performance was measured by dynamic mechanical analysis (DMA) and tensile tests. Besides, thermal properties were measured by differential scanning calorimetry (DSC), where the melting temperature of crystalline PCO phase around 40–50 °C were observed. Considering this shape memory triggering temperature, the shape memory capabilities of the samples were studied by thermo-mechanical analysis (TMA), and outstanding shape recovery ratios were obtained. Finally, water contact angle (WCA) and water vapour transmission rate (WVTR) were measured above and below that transition temperature to assess moisture permeability changes. In this case, observed increase by an order of magnitude in vapour permeability with temperature offers promising opportunities in developing thermo-active membranes for textile applications with these PCO-LLDPE blends.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719309899-ga1.jpg" width="365" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Busra Tugce Duymaz, Fatma Betul Erdiler, Tugba Alan, Mehmet Onur Aydogdu, Ahmet Talat Inan, Nazmi Ekren, Muhammet Uzun, Yesim Muge Sahin, Erdi Bulus, Faik Nüzhet Oktar, Sinem Selvin Selvi, Ebru ToksoyOner, Osman Kilic, Muge Sennaroglu Bostan, Mehmet Sayip Eroglu, Oguzhan Gunduz〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Poly(ε-caprolactone) (PCL), gelatin (GT) and different concentrations of low molecular weight 〈em〉Halomonas〈/em〉 levan (HLh) were combined and examined to develop physical networks serving as tissue scaffolds to promote cell adhesion for biocompatibility. Three-dimensional bioprinting technique (3D bioprinting) was employed during manufacturing the test samples and their comprehensive characterization was performed to investigate the physicochemical properties and biocompatibility. Physical properties of the printing materials such as viscosity, surface tension, and density were measured to determine optimal parameters for 3D bioprinting. The scanning electron microscope (SEM) was used to observe the morphological structure of scaffolds. Fourier-Transform Infrared Spectroscopy (FT-IR) and differential scanning calorimetry (DSC) were used to identify the interactions between the components. 〈em〉In-vitro〈/em〉 cell culture assays using standard human osteoblast (Hob) cells showed increased biocompatibility of the printing materials with increasing HLh content. Thus, the formulations including the HLh are expected to be a good candidate for the production of 3D printed materials.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719313862-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Maria A. Murcia Valderrama, Robert-Jan van Putten, Gert-Jan M. Gruter〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Plastic materials are indispensable in everyday life because of their versatility, high durability, lightness and cost-effectiveness. As a consequence, worldwide plastic consumption will continue to grow from around 350 million metric tons per annum today to an estimated 1 billion metric tons per annum in 2050. For applications where polymers are applied in the environment or for applications where polymers have a bigger chance of ending up in the environment, (bio)degradable polymers need to be developed to stop endless accumulation of non-degradable polymers irreversibly littering our planet.〈/p〉 〈p〉As monomers and polymers represent more than 80% of the chemical industry’s total production volume, a transition from fossil feedstock today (99% of the current feedstock for polymers is fossil-based) to a significantly larger percentage of renewable feedstock in the future (carbon that is already “above the ground”) will be required to meet the greenhouse gas reduction targets of the Paris Agreement (〉80% CO〈sub〉2〈/sub〉 reduction target for the European Chemical Industry sector in 2050).〈/p〉 〈p〉The combination of the predicted polymer market growth and the emergence of new feedstocks creates a fantastic opportunity for novel sustainable polymers. To replace fossil based feedstock, there are only three sustainable alternative sources: biomass, CO〈sub〉2〈/sub〉 and existing plastics (via recycling). The ultimate circular feedstock would be CO〈sub〉2〈/sub〉: it can be electrochemically reduced to formic acid derivatives that can subsequently be converted into useful monomers such as glycolic acid and oxalic acid. In order to assess the future potential for these polyester building blocks, we will review the current field of polyesters based on these two monomers. Representative synthesis methods, general properties, general degradation mechanisms, and recent applications will be discussed in this review. The application potential of these polyesters for a wide range of purposes, as a function of production cost, will also be assessed. It is important to note that polymers derived from CO〈sub〉2〈/sub〉 do not necessarily always lead to lower net overall CO〈sub〉2〈/sub〉 emissions (during production of after use, e.g. degradation in landfills). This needs to be evaluated using robust LCA’s and this information is currently not available for the materials discussed in this review.〈/p〉 〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719309164-ga1.jpg" width="260" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Kunshan Ding, Yajie Zhang, Zhihao Huang, Baolei Liu, Qiunan Shi, Lihua Hu, Nianchen Zhou, Zhengbiao Zhang, Xiulin Zhu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Digital polymers with precise arrangements of units acting as the 0- or 1-bit, have shown bright promise for the data storage media. The easiness of encoding and decoding these polymers is essential when putting them into practical applications. Herein, the concept of utilizing sequence building block and sequencing indicator to generate easily encodable and decodable digital polymers is proposed. With the thiol-maleimide Michael coupling for digital chain growth, the dithiosuccinimide (DTS) motifs generated from the succinimide thioether linkages are used as the sequence building block. The DTS can be equipped with different groups, thus greatly enabling the modular encoding process. Importantly, the tandem mass spectrometry (MS/MS) results unveil the relatively abundant DTS-induced MS signal, which facilitates the decoding process with DTS acting as the sequencing indicator. The synergetic MS/MS induced cleavages of the two C〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉S bonds on DTS are responsible for the relatively abundant MS signal. Finally, the work exemplifies the quantitatively decoding of a digital polymer with DTS as the sequence building block and sequencing indicator. This study demonstrates the concept of sequence building block and sequencing indicator, which advances the digital polymers for practical applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉The easily encodable and decodable digital polymer using dithiosuccinimide as sequence building block and sequencing indicator was proposed.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719310225-ga1.jpg" width="253" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Fatemeh Zarei, Azam Marjani, Roozbeh Soltani〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉To capture heavy metals in aqueous solution, it is imperative to develop viable and safe heavy metals uptake techniques. Herein, we report polymer matrix nanocomposite adsorbents with 2 and 5 wt.% nanofiller contents based on functionalised mesoporous fibrous silica KCC-1, chitosan, and oleic acid (abbreviated as TA-KCC-1/Chi-OLA NC). TA-KCC-1/Chi-OLA NCs relying on physicochemical adsorption are potential candidates for heavy metals removal because of their facile fabrication procedure, low toxicity, biodegradability, and high affinity toward heavy metals. The adsorption of Pb(II) cations onto green TA-KCC-1/Chi-OLA 5 wt.% adsorbent was studied in the batch system. Langmuir and pseudo-second-order models were found to be the best fit models to predict isotherms and kinetics of adsorption, respectively. The maximum adsorption capacity according to the Langmuir model was 168 mg g〈sup〉−1〈/sup〉 (adsorption conditions: pH: 9.0, adsorbent dose: 20.0 mg; contact time: 100 min; initial concentration: 100 mg L〈sup〉−1〈/sup〉).〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719312339-ga1.jpg" width="399" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Benjámin Gyarmati, Béla Pukánszky〈/p〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 118〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Andrés Felipe Chamorro Rengifo, Natalia Marcéli Stefanes, Jessica Toigo, Cassiana Mendes, Débora Fretes Argenta, Marta Elisa Rosso Dotto, Maria Cláudia Santos da Silva, Ricardo José Nunes, Thiago Caon, Alexandre Luis Parize, Edson Minatti〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Intact carboxymethyl-hexanoyl chitosan/dodecyl sulfate nanoparticles loaded with pyrazoline H3TM04 were dispersed in biodegradable PEO-chitosan nanofiber mats (PEOChNps) for application in skin cancer treatment. The nanomaterial was formed by co-electrospinning in aqueous solution. The structural and morphological properties of the PEOChNps were investigated by FEG-SEM, TEM, AFM, FTIR, DSC and TGA. The PEOChNps nanofibers showed a narrow size distribution (197.8 ± 4.1 nm) with a homogenous distribution of the nanoparticles inside the nanofibers, promoting the controlled release of H3TM04 from both diffusion and erosion processes over a period of 120 h. An increased transport rate of H3TM04 through the epidermis was also found when PEOChNps was used as the carrier. In 〈em〉in vitro〈/em〉 cytotoxicity assays, the incorporation of H3TM04 into the nanocarriers increased its cytotoxic effect toward B16F10 melanoma cells. These findings suggest that the proposed nanofiber mats could be used for controlled drug release in local chemotherapy treatment for skin cancer.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719311279-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Javier Quílez-Bermejo, Alessio Ghisolfi, Daniel Grau-Marín, Emilio San-Fabián, Emilia Morallón, Diego Cazorla-Amorós〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉P-postmodified polyaniline was obtained by reacting phosphorus trichloride (PCl〈sub〉3〈/sub〉) and chlorodiphenylphosphine (PPh〈sub〉2〈/sub〉Cl) and polyaniline (PANI), under mild conditions. The reaction was found to be very selective, as only the imine groups were involved in the P-functionalization, and efficient as well, affording a P-loading of 3 at.% and 5 at.% for PPh〈sub〉2〈/sub〉Cl and PCl〈sub〉3〈/sub〉, respectively. All the polymers were characterized by different techniques and the results were endorsed by theoretical calculations. Experimental and Density Functional Theory results proved that the reaction occurs through the imine groups and the phosphorus atoms, generating N〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉P bonds. The electrochemical properties of the N〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉P modified materials were evaluated and the catalytic activity towards oxygen reduction reaction was measured. It was found that a high concentration of phenyl groups from PPh〈sub〉2〈/sub〉Cl (about 3 at.%) affected negatively the activity of the catalyst since they prevented the access of the oxygen molecules to the catalytic active sites. However, a lower amount of 〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉PPh〈sub〉2〈/sub〉 groups (1 at.%) or the use of PCl〈sub〉3〈/sub〉 avoided this hindrance and resulted in an improved catalytic activity with respect to pristine PANI.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719309231-ga1.jpg" width="273" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 118〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Arpit Shukla, Krina Mehta, Jignesh Parmar, Jaimin Pandya, Meenu Saraf〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Microorganisms can utilize an extensive assortment of carbon and nitrogen sources as well as various added nutrients ranging from simple to complex. Depending on the microbe and the metabolic pathway they undergo, these nutrients are efficiently converted into complex and diverse biopolymers with varied physico-chemical properties. Exopolysaccharides (EPS) are biopolymers that primarily contain- carbohydrates. The extensively studied EPS producing bacteria include 〈em〉Leuconostoc mesenteroides〈/em〉, 〈em〉Xanthomonas campestris〈/em〉, 〈em〉Acinetobacter calcoaceticus, Lactobacillus sp〈/em〉. and 〈em〉Alkaligenes〈/em〉 sp. However, some prominent fungal exopolysaccharides produced by 〈em〉Aspergillus niger〈/em〉, 〈em〉Lentinula edodes〈/em〉, 〈em〉Fusarium solani〈/em〉, 〈em〉Botryosphaeria rhodina〈/em〉, 〈em〉Coriolus versicolor〈/em〉 have also been put to commercial use. While the microbes may vary substantially in their physiology, the production of EPS depends largely on the optimization of the growth by varying various parameters influencing growth and the meticulous designing of its production media. EPS acts as an invaluable asset for the producing microbe by providing manifold benefits including but not restricted to: protection against- desiccation, starvation, phagocytosis, UV radiation, environmental stress and water retention. Being eco-friendly and biodegradable, major microbial EPS such as; dextran, xanthan, alginate, hyaluronan, pullulan, chitosan and lentinam have found numerous vital applications in pharmaceutical, agriculture, food and cosmetics industries. This review provides an inclusive insight into the world of microbial exopolysaccharides covering its major aspects, namely- its types, biosynthesis and the factors that influence its production along with various techniques used for its recovery and further characterization. Special emphasis is placed on the applications of EPS in various large-scale commercial and industrial sectors.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719307815-ga1.jpg" width="291" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Suzhen Liu, Li Zhang, Xiaohong Chen, Tingting Chu, Yanzhu Guo, Meihong Niu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel kind of cationic cellulose-〈em〉g〈/em〉-oligo(ε-caprolactone) amphiphilic polymer (QC-〈em〉g〈/em〉-OCL) was obtained by homogeneous ring-opening polymerization of ε-caprolactone (ε-CL) from quaternized cellulose (QC) in 1-butyl-3-methylimidazolium chloride (BmimCl) ionic liquids. Chemical structures and properties of the copolymers were characterized by FT-IR, 〈sup〉1〈/sup〉H NMR, 〈sup〉13〈/sup〉C NMR, XRD and TGA techniques. The grafting ratios of OCL chain onto QC-〈em〉g〈/em〉-OCL were adjusted by changing the molar ratio of CL to QC. The micelles self-assembled from QC-〈em〉g〈/em〉-OCL were prepared by ultrasonic-assisted dissolution method, and comprehensively analyzed by dynamic light scattering (DLS), TEM and fluorescence spectroscopy techniques. The micelles were in spherical shape with average hydrodynamic radiuses (R〈sub〉h〈/sub〉) in the range of 170–237 nm. Moreover, their critical micelle concentration (CMC) values were decreased from 0.302 mg/mL to 0.089 mg/mL with increasing the degree substitution values of OCL (DS〈sub〉OCL〈/sub〉) from 0.16 to 0.60. The ζ-potentials of micelles in water were ranged from 37.2 mV to 48.3 mV, indicating that the shells of micelles were constituted by ationic quaternary ammonium group. All of these findings established that the cationic cellulose-based micelles would be a promising aqueous carrier for hydrophobic drug.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719312662-ga1.jpg" width="343" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: September 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 118〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Isao Yamaguchi, Gintaro Nagase, Aohan Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The reaction of 〈em〉N〈/em〉-(2,4-dinitrophenyl)pyridinium chloride (〈strong〉salt(Cl〈sup〉−〈/sup〉)〈/strong〉) with lithium bis(trifluoromethanesulfonyl)imide (TFSI〈sup〉−〈/sup〉LI〈sup〉+〈/sup〉) and lithium bis(nonafluorobutanesulfonyl)imide (NFSI〈sup〉−〈/sup〉LI〈sup〉+〈/sup〉) resulted in the anion exchange between Cl〈sup〉−〈/sup〉 and TFSI〈sup〉−〈/sup〉 and Cl〈sup〉−〈/sup〉 and NFSI〈sup〉−〈/sup〉 that yielded new Zincke salts, namely 〈strong〉salt(TFSI〈sup〉−〈/sup〉)〈/strong〉 and 〈strong〉salt(NFSI〈sup〉−〈/sup〉)〈/strong〉, respectively. The reaction of 〈strong〉salt(TFSI〈sup〉−〈/sup〉)〈/strong〉 with piperazine, (〈em〉R〈/em〉)-(–)- or (〈em〉S〈/em〉)-(+)-2-methylpiperazines in methanol without the use of a catalyst resulted in the opening of pyridinium ring to yield ionic polymers with 5-piperazinium-2,4-dienylideneammonium bis(trifluoromethanesulfonyl)imide or 5-(2-methylpiperazinium)-2,4-dienylideneammonium bis(trifluoromethanesulfonyl)imide units, namely 〈strong〉polymer(H;TFSI〈sup〉−〈/sup〉)〈/strong〉, 〈strong〉polymer(〈em〉R〈/em〉-Me;TFSI〈sup〉−〈/sup〉)〈/strong〉, and 〈strong〉polymer(〈em〉S〈/em〉-Me;TFSI〈sup〉−〈/sup〉)〈/strong〉, respectively. The reaction of 〈strong〉salt(NFSI〈sup〉−〈/sup〉)〈/strong〉 with piperazine yielded 〈strong〉polymer(H;NFSI〈sup〉−〈/sup〉)〈/strong〉 having a 5-piperazinium-2,4-dienylideneammonium bis(trifluoromethanesulfonyl)imide unit. Model compounds with TFSI〈sup〉−〈/sup〉 or NFSI〈sup〉−〈/sup〉 were synthesized to compare their structures and chemical propeties with those of the corresponding polymers. UV–vis measurements revealed that the π-conjugation system expanded along the polymer chain due to the orbital interaction between the electrons on the two nitrogen atoms of the piperazinium or 2-methylpiperazinium rings. Cyclic voltammetry analysis suggested that the polymers obtained in this study received electrochemical oxidation and reduction.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719307177-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Kenji Kanazawa, Sei Uemura〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Herein, electrochromic terpyridine-triphenylamine (Terpy-TPA) polymer films were prepared by electropolymerization of a Terpy-TPA monomer solution in acetonitrile:toluene (1:4, v/v) and. characterized by cyclic voltammogram and absorption spectra in a 50 mM aqueous tetramethylammonium perchlorate as an electrolyte using a standard three-electrode system. The above films could be reversibly color changes between orange (neutral state) and cyan (oxidized state) and maintained a high coloration efficiency of 229 cm〈sup〉2〈/sup〉 C〈sup〉−1〈/sup〉 at 750 nm in the aqueous electrolyte solution.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719312753-ga1.jpg" width="442" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: October 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 119〈/p〉 〈p〉Author(s): Mostafa Khoshsefat, Abbas Dechal, Saeid Ahmadjo, S. Mohammad M. Mortazavi, Gholamhossein Zohuri, Joao B.P. Soares〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We designed a series of dinuclear structures (F〈sub〉1〈/sub〉–F〈sub〉5〈/sub〉) bearing different linkers (rigid to flexible) between the Fe centers to investigate that how they could control the catalyst behaviour and polymer properties. The dinculear structures were used for polymerization of ethylene in presence of MMAO and TiBA. Based on initial results, catalyst F〈sub〉2〈/sub〉 containing methyl-substituted phenyl bridge owned the highest activity (4.9 × 10〈sup〉6〈/sup〉 g PE/mol Fe.h) through dinuclearity and optimum bulkiness among the structures studied. This performance was along with the greatest crystallinity (χ〈sub〉c〈/sub〉) of PE made by the catalyst. Polymerization at higher temperature and monomer pressure exhibited high thermal stability and performance of catalyst F〈sub〉2〈/sub〉, respectively. For further structures, decreasing of effective electronic and steric features led to lower activity. In addition, not only catalyst F〈sub〉4〈/sub〉 bearing the short ethylene bridge exhibited the lowest productivity, but also produced the PE containing high level of short chain branches (37.2 SCB/1000C) affording a branched microstructure of polyethylene in presence of TiBA. It could attribute to low steric and electronic effects and short distance between the centers (ethylene linker) that made it suitable and active for SCB formation. Regarding to it, the electrophilicity index (ω) of F〈sub〉4〈/sub〉 also was greater that led to high capacity or propensity of the specie to accept the (macro) monomer. For this sample, virtually no χ〈sub〉c〈/sub〉 observed in DSC and SSA thermograms. Moreover, MMAO acted as an effective cocatalyst in comparison to TiBA, according to the kinetic profiles of ethylene polymerization. The observations were in respect of strength and affinity of the cocatalysts in deactivation and reactivation of the centers at prolonged time.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719312078-ga1.jpg" width="355" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 31 October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Ali Behnood, Mahsa Modiri Gharehveran〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Asphalt binders play an integral role in the performance and properties of asphalt mixtures. Increased traffic-related factors on the roadways such as heavier loads, higher traffic volume, and higher tire pressure combined with substantial variation in daily and seasonal temperatures of the pavement have been responsible for the asphalt pavements failure. To prevent or mitigate these failures, many attempts have been made by polymer scientists and civil engineers to improve the performance of asphalt pavements by modifying the properties of asphalt binders. A good modifier changes the failure properties such that binder yields more stresses and strains before failure. Modification of asphalt binders through the addition of a polymer to improve their rheological and physical properties has a long history in asphalt industry. Once the polymer is properly mixed with the asphalt binder, a swallowed polymer network is formed, which contributes to the changes in viscoelastic behavior. However, polymer-modified asphalt binders may have some drawbacks related to the poor solubility of polymers. Understanding the internal structure of polymer-modified asphalt binders has been the subject of numerous research studies.〈/p〉 〈p〉Available studies regarding the affecting parameters on the properties of the polymer-modified asphalt binders are reviewed here. Various types of polymers used in asphalt industry and their effects on the rheological, morphological, physical and mechanical properties of polymer-modified asphalt binders are also discussed in this paper. In addition, this paper provides a review on the techniques used to overcome/mitigate the shortcomings of conventional polymer-modified asphalt binders.〈/p〉 〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718318019-ga1.jpg" width="341" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Barbara Fahrngruber, Johanna Eichelter, Sabine Erhäusl, Bernhard Seidl, Rupert Wimmer, Norbert Mundigler〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The implementation of bio-based additives in polymer formulations provides possibilities to tailor material characteristics for more sustainable solutions. Fibers derived from natural sources and of sustainable origin have been gaining importance for bio-based as well as biodegradable packaging, showing also high performance. In this research, potato-fiber modified thermoplastic starch (TPS, fiber contents 1, 3 and 5 wt%) was prepared, which was used in the subsequent production of TPS/polyester compounds. Characterization results revealed a reduced formation of closely-packed crystalline structures in TPS, along with increasing fiber content. Likewise, an increase in materials rigidity was observed, as determined via dynamic mechanical analysis. Within the compounded material, potato-fiber additions enhanced a molecular weight reduction in starch while the formation of agglomerates was induced. The prepared films exhibited increased mechanical stiffness and also modified sorption characteristics. The identified property profiles are instrumental in creating novel, custom-tailored packaging materials.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718316768-ga1.jpg" width="356" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 31 October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Aide Wu, Nurettin Sahiner, Wayne F. Reed〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Using time resolved total intensity light scattering a two phase process was found in the conversion of 2-(3,4-dihyroxyphenyl)ethylamine, dopamine (DP), into microparticles. Phase 1 appears to involve oxidation of the DP, and may also include oligomerization below the light scattering threshold of detectability. After a certain lag time, the ‘Phase 1 Period’ (P1P), dependent upon reaction conditions, the light scattering increases sharply, heralding the onset of Phase 2. Precipitating particles are eventually formed in latter Phase 2. The solution goes through a series of color changes throughout Phase 1 and 2, starting as pink in Phase 1, and culminating in black particles in Phase 2. The reaction proceeds under virtually any conditions; purged with O〈sub〉2〈/sub〉 or N〈sub〉2〈/sub〉, unpurged, stirred or unstirred, under different pH conditions, etc. Stirring, increasing temperature, and adding potassium persulfate (KPS), all accelerate the reaction. 〈em〉P1P varied over nearly four orders of magnitude, from 10 s (pH〈sub〉initial〈/sub〉 = 9.5) to 8 × 10〈sup〉4〈/sup〉 s (T = 25 °C, no pH control).〈/em〉 Arrhenius behavior is found for P1P with low activation energies in the range of 10–25 Kcal/Mole. The precipitating particulates rapidly formed in Phase 2 suggest that they may involve non-covalent associations of oligomers formed in Phase 1, possibly due to loss of oligomeric solubility, in addition to possibly involving covalent polymer branching and cross-linking. Non-covalent aggregation of oligomers formed in Phase 1 seems most likely.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718316203-ga1.jpg" width="295" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 110〈/p〉 〈p〉Author(s): Ruiyu Wang, Jianping Pan, Meng Qin, Tianying Guo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, macro cyclic amine type of functional monomers, (4-vinylbenzyl)-1,4,7-triazacyclononane (VBTN) and 1,4-bishydroxyethyl-7-(4-vinylbenzyl)-1,4,7-triazacyclononane (VBTNOH), were synthesized to prepare enzyme-mimic molecular imprinting polymers (MIPs) nanoparticles with the hollowed morphology, which are expected to eliminate organophosphorus pesticide pollutants. The resulted MIPs show higher catalytic hydrolysis activity compared to the self-hydrolysis of substrate methyl parathion. Especially, the MIP with functional monomer containing alcohol assistant group (MIP-VBTNOH), shows the best performance, whose initial rate is 3.51 * 10〈sup〉−2〈/sup〉 mM/h, 415-fold higher than substrate self-hydrolysis. Its Michaelis-Menten constant is as low as 0.87 mM. We attribute the good performance of MIP-VBTNOH to its alcohol assistant group on the funcional monomers because the alcohol OH is more nucleophilic than water. Such mechanism is confirmed by the observation of the intermediate in this catalytic process by 〈sup〉31〈/sup〉P NMR spectrum. In addition, the introduce of hollowed nanocapsule morphology makes MIPs effectively absorb p-nitrophenol produced by the hydrolysis of organophosphate compounds, another pollutant needs to be eliminated.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718317464-ga1.jpg" width="408" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 109〈/p〉 〈p〉Author(s): Claire Negrell, Coline Voirin, Bernard Boutevin, Vincent Ladmiral, Sylvain Caillol〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Chemistry in general, but polymer chemistry in particular has to face the major challenge of finding solutions to ensure a sustainable and environmental-benign development of industry to answer consumer needs. Aldehydes are very important chemical groups for polymer science of the synthesis of phenolic resins for example, however, most molecular aldehydes (such as formaldehyde) are toxic. Finding less toxic and sustainable aldehydes is not easy because this functional group is relatively scarce in nature. In consequence aldehydes-containing building blocks must be synthesized. The present review gives an overview of the different synthetic methods to prepare such aldehyde building blocks. It then focusses on the use of radically polymerizable aldehyde-containing monomers to prepare polymers and materials featuring available aldehyde pendent group. Indeed, owing to the rich reactivity and properties of aldehydes, such functional polymers will undoubtedly lead to the development of high-added value applications. This review also gives a brief overview of such potential applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718315982-ga1.jpg" width="331" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 28 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Chi-Chi Chang, Yung-Chi Chang, Wei-Yi Lu, Yi-Chun Lai, Kuo-Hui Wu, Ya-Fan Lin, Hsuan-Ying Chen〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A series of Al complexes bearing diethyl 2-((arylamino)methylene)malonate and diethyl 2-((alkylamino)methylene)malonate ligands (AMM ligands) were synthesized and their application in the ring-opening polymerization of 〈em〉ε〈/em〉-caprolactone was studied. All the Al complexes bearing AMM ligands exhibited higher catalytic activity (approximately 2.8–16.5 fold) than those Al complexes bearing ketiminate ligands did, except 〈strong〉O〈sup〉iPr〈/sup〉AlMe〈sub〉2〈/sub〉〈/strong〉 (2 fold lower catalytic activity). In addition, Al complexes with steric hindrance or electron-withdrawing groups in the ligands revealed the greater catalytic activity, and the chelating effect reduced the reactivity of ring-opening polymerization.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719300898-ga1.jpg" width="317" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 28 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Xiaoran Hu, Yan Li, Yu Gao, Runguo Wang, Zhao Wang, Hailan Kang, Liqun Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Poly (butylene succinate) (PBS) is one of the most mature Bio-based plastics in the current market. However, its excellent mechanical properties are disappointed eclipsed by its inherent poor toughness. Herein, a novel bio-based elastomer poly (2,3-butanediol-〈em〉co〈/em〉-1,4-butanediol-〈em〉co〈/em〉-succinate) (PBBS) was designed and synthesized from three bio-based monomers in order to improve the toughness of PBS. Butanedio and succinic acid were used to ensure a good compatibility between PBBS and PBS, while 2,3-BDO was introduced into PBBS to inhibit the crystallization of PBBS and promote high elasticity of PBBS. Besides, 2,3-BDO could tailor the compatibility between PBBS and PBS and helps to adjust the phase separated structure. The elongation at break and impact strength of the PBBS/PBS blend could improve from 350% and 4.7 kJ/m〈sup〉2〈/sup〉 to 525% and 41.7kJ/m〈sup〉2〈/sup〉 compared with the neat PBS. The synthesized PBBS shows a super toughing effect on PBS without any compatilizer, which could contribute to a wider application of PBS.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719304823-ga1.jpg" width="489" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 28 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Taras Kavetskyy, Oleh Smutok, Olha Demkiv, Sigita Kasetaite, Jolita Ostrauskaite, Helena Švajdlenková, Ondrej Šauša, Khrystyna Zubrytska, Nataliia Hoivanovych, Mykhailo Gonchar〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Laccase-based amperometric enzyme biosensors of the third generation for analysis of phenol derivates have been constructed using graphite rods (type RW001) as working electrodes and the photocross-linked polymers as a matrix. Such matrix consisted of epoxidized linseed oil (ELO), bisphenol A diglycidyl ether (RD) as reactive diluent and 50% mixture of triarylsulfonium hexafluorophosphate in propylene carbonate (PI) as photoinitiator. The synthesis was made by the reaction of ELO and 10 mol.% or 30 mol.% of RD, using 3 mol.% of PI (ELO/10RD and ELO/30RD, respectively). The holding matrixes were used for an immobilization of commercial laccase from the fungus 〈em〉Trametes versicolor〈/em〉. The network properties of the polymer matrixes, holding biosensing element, were studied by means of swelling and positron annihilation lifetime spectroscopy measurements. The amperometric enzyme biosensor parameters were evaluated using cyclic voltamperometry and chronoamperometric analysis. A correlation between the constructed biosensor parameters and microscopical free volume of the biosensor holding matrixes was established.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001430571930463X-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 27 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Youyan Wei, Xubao Jiang, Shusheng Li, Xiang Zheng Kong〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Highly uniform polymer microspheres are widely used for a variety of applications. Uniform polyurea (PU) microspheres have been prepared by precipitation polymerization of isophorone diisocyanate (IPDI) in a binary mixture of H〈sub〉2〈/sub〉O-acetone (AT). With AT replaced by N,N′-dimethylformamide (DMF) in the binary mixture, a significant acceleration effect is observed. Through measurements of the solubility of IPDI and its polymer in the binary solvents of different composition, catalytic effect of DMF is confirmed, and a mechanism of catalysis is proposed. The polymerization is carried out at different temperature with varied IPDI concentration in H〈sub〉2〈/sub〉O/DMF or H〈sub〉2〈/sub〉O/AT/DMF of different composition, with objective to optimize the preparation of PU microspheres. The results demonstrate that, with the polymerization done at 60 °C in a ternary mixture of H〈sub〉2〈/sub〉O-DMF-AT, highly uniform PU microspheres are well formed with IPDI concentration of up to 13.0 wt%, which represents an increase of 3 wt% compared to the highest IPDI concentration allowed to have these microspheres in the binary solvent of H〈sub〉2〈/sub〉O-AT. This is also accomplished in an obviously shortened time. PU structure and properties are briefly discussed. This work provides a simple and fast protocol for large-scale production of uniform and functional PU microspheres with DMF as a cosolvent and catalyst.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718325266-ga1.jpg" width="291" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 27 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Svetlana A. Sorokina, Yulia Yu. Stroylova, Sofia A. Tishina, Zinaida B. Shifrina, Vladimir I. Muronetz〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Misfolding and aggregation of amyloidogenic proteins are responsible for the onset of neurodegenerative diseases. This makes studies directed towards prevention of these processes of particular importance. In this paper we report that cationic pyridylphenylene dendrimers of the second (G2), third (G3) and fourth (G4) generations act as effective suppressors of the amyloid aggregation of the full-length ovine prion protein (PrP). The dendrimers are able to inhibit both the formation of the most toxic soluble oligomers and amyloid fibrils. Dendrimer binding prevents the structural conversion of PrP and further protein fibrillation. The effect is dependent on the dendrimer generation with G4 being the most potent. Importantly, after the treatment with the dendrimers, PrP does not induce the pathological conformational changes in native PrP, indicating the loss of amyloidogenic properties. The cell viability assay reveals the dependence on the cell line and the dendrimer generation used. The observed fundamental principles of the dendrimer interaction with PrP helped us to elucidate the protective effect of the dendrimers and to suggest the potential mechanism of the dendrimer action. Noteworthy, the dendrimers preserve their protective effect regardless of the aggregation conditions applied, indicating the important role of their structural features, e.g. rigidity and permanent charge, in anti-amyloid behavior.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718322122-ga1.jpg" width="289" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 30 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Blanca S. Pascual, Miriam Trigo-López, José A. Reglero Ruiz, Jesús L. Pablos, Juan C. Bertolín, César Represa, José V. Cuevas, Félix C. García, José M. García〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We prepared microporous aramid films through a simple, inexpensive and green way, using ionic liquids (IL) as porosity promoters. Commercial poly(m-phenylene isophthalamide) (MPIA) films with different IL proportions were prepared, and then microporous films were obtained by removing the IL in distilled water. Microporous films presented density values between 0.34 and 0.71 g⋅cm〈sup〉-3〈/sup〉 (around five times lower to commercial MPIA), with a homogeneous and controlled cellular morphology dependent on the proportion of the IL, showing cell sizes in the microcellular range (radii between 1 and 8 µm). Thermal, mechanical and electrical properties (specifically ionic conductivity) of the aramid films were analyzed to evaluate the influence of the IL proportion. Finally, it was observed that the MPIA/IL system presented a reversible thermally induced phase-separation process around 60 °C, which was characterized through AFM-Raman images and spectra, together with the variation of the ionic conductivity.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719302940-ga1.jpg" width="266" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 29 March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Clément Lacoste, José-Marie Lopez-Cuesta, Anne Bergeret〈/p〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718321566-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 110〈/p〉 〈p〉Author(s): Hao Jiang, Haiyan Peng, Guannan Chen, Honggang Gu, Xiuguo Chen, Yonggui Liao, Shiyuan Liu, Xiaolin Xie〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Ordered materials, which hold organized structures of heterogeneous matter and thus always present superior performance than their non-ordered counterparts, have been constantly pursued. Nevertheless, the direct, precise and nondestructive observation of the ordering process, which is especially critical for evaluating the quality of consecutive manufacturing, remains a formidable challenge. Herein, we introduce Mueller matrix ellipsometry (MME) as a nondestructive method to quantitatively investigate the nanocomposite ordering process upon holography. This nondestructive investigation directly offers the exact width of, refractive index and nanoparticle fraction in each bright (constructive) and dark (destructive) interference area, which is impossible to be implemented using other existing techniques. Interestingly, the width of dark regions in the formed holographic gratings is observed to decrease while the width of bright regions increases with an augmentation of holographic recording time, distinct from previous width-equal assumption. Meanwhile, an apparent diffusion coefficient of 2 × 10〈sup〉−15〈/sup〉 m〈sup〉2〈/sup〉 s〈sup〉−1〈/sup〉 for nanoparticles is determined on the basis of time dependent grating parameter variation, which is 3 orders of magnitude lower than the initial value theoretically predicted by the Stokes-Einstein diffusion equation. The distinct diffusion coefficient is attributed to the rapid increase of viscosity driven by polymerization during holography. No depolarization is observed in these holographic polymer nanocomposites, indicating uniform dispersion of nanoparticles in the polymer matrices. The proposed protocol herein is envisioned to pave the way for precisely and nondestructively understanding the formation of ordered structure in electronics, photonics, photovoltaics, biomaterials and other disciplines.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718314824-ga1.jpg" width="263" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Yue Han, Donghao Tang, Guangxing Wang, Ying Guo, Heng Zhou, Wenfeng Qiu, Tong Zhao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Low melting phthalonitrile monomers containing allyl and/or methoxyl groups were designed, synthesized and characterized. In order to evaluate their potential application in phthalonitrile resins, these monomers were blended with 1,3-bis(3,4-dicyanophenoxy)benzene and 4-(4-aminophenoxy)phthalonitrile, then cured into polymers. Curing mechanisms of different prepolymers were proposed and compared, and processability, thermal and mechanical properties were characterized. The introduction of methoxyl units was found to postpone the curing, and thermal properties were slightly compromised. On the contrary, the usage of allyl was beneficial to both processability and thermal properties. More importantly, the impact strength for allyl-containing polymers could be as high as 13.63 kJ m〈sup〉−2〈/sup〉, indicating such resin could be applied as high temperature structural composite matrices.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718321232-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Arkadiusz Zych, Alice Verdelli, Maria Soliman, Roberta Pinalli, Alessandro Pedrini, Jérôme Vachon, Enrico Dalcanale〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉High Density and Very Low Density PolyEthylene-〈em〉graft〈/em〉-Maleic AnHydride (HDPE-MAH and VLDPE-MAH respectively) functionalized with 1-aminopyrene (AP) are prepared via reactive extrusion. Covalent attachment of AP is confirmed by lack of residual free AP after extraction with dichloromethane. Differential scanning calorimetry, tensile test, dynamical mechanical thermal analysis and rheology are employed to investigate the influence of AP incorporation on thermal, mechanical and rheological properties when grafted on both HD and VLDPE-MAHs. Fluorescent emission spectroscopy reveals pronounced changes in fluorescent behavior under stress due to the breakup of the pyrene excimers. For HDPE-MAH-AP this change is sudden with a clear drop of excimer content (I〈sub〉E〈/sub〉/I〈sub〉M〈/sub〉) of around 50% due to necking of the material stretched above 50% strain. In contrast, VLDPE-MAH-AP shows no necking and a linear decrease of I〈sub〉E〈/sub〉/I〈sub〉M〈/sub〉 ratio down to 30% when elongated up to 1100% strain, while HDPE-MAH-AP broke after 200% strain.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718316069-ga1.jpg" width="278" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 10 October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Laura Lemetti, Sami-Pekka Hirvonen, Dmitrii Fedorov, Piotr Batys, Maria Sammalkorpi, Heikki Tenhu, Markus B. Linder, A. Sesilja Aranko〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Gaining insights into the processes that transform dispersed biopolymers into well-ordered structures, such as soluble spidroin-proteins to spider silk threads, is essential for attempts to understand their biological function and to mimic their unique properties. One of these processes is liquid-liquid phase separation, which can act as an intermediate step for molecular assembly. We have shown that a self-coacervation step that occurs at a very high protein concentration (〉200 gl〈sup〉−1〈/sup〉) is crucial for the fiber assembly of an engineered triblock silk-like molecule. In this study, we demonstrate that the addition of a crowding agent lowers the concentration at which coacervation occurs by almost two orders of magnitude. Coacervates induced by addition of a crowding agent are functional in terms of fiber formation, and the crowding agent appears to affect the process solely by increasing the effective concentration of the protein. Furthermore, induction at lower concentrations allows us to study the thermodynamics of the system, which provides insights into the coacervation mechanism. We suggest that this approach will be valuable for studies of biological coacervating systems in general.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718316665-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 11 October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Xiongliang He, Rongtao Zhou, Chenglong Ge, Ying Ling, Shifang Luan, Haoyu Tang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The understanding of molecular structure and thermoresponsive property relationships and development of water-soluble thermoresponsive polymers with tunable cloud point temperatures (〈em〉T〈/em〉〈sub〉cp〈/sub〉s) are crucial toward versatile practical uses. Herein, OEGylated polypeptides bearing Y-shaped pendants, namely poly(γ-4-(propoxycarbonyl)benzyl-〈sub〉L〈/sub〉-glutamate)-oligo(ethylene glycol) conjugates (8-OEG〈em〉x〈/em〉, 〈em〉x〈/em〉 = 2, 3) were synthesized by the combination of ring-opening polymerization of γ-4-(allyloxycarbonyl)benzyl-〈sub〉L〈/sub〉-glutamic acid based 〈em〉N〈/em〉-carboxyanhydride (〈strong〉4〈/strong〉) and subsequent side-chain modifications, including bromination of poly(γ-4-(allyloxycarbonyl)benzyl-〈sub〉L〈/sub〉-glutamate) (〈strong〉5〈/strong〉), nucleophilic substitution of 〈strong〉5〈/strong〉 in the presence of NaN〈sub〉3〈/sub〉, and subsequent copper-mediated 1,3-dipolar cycloaddition. Both 〈sup〉1〈/sup〉H NMR and FTIR analysis confirmed the molecular structures of the intermediates and 8-OEG〈em〉x〈/em〉. In aqueous solutions, 8-OEG〈em〉x〈/em〉 samples showed reversible lower critical solution temperature (LCST)-type phase transitions in broad polymer concentration range (0–30 mg·mL〈sup〉−1〈/sup〉). Variable-temperature UV–vis spectroscopy results revealed that the LCST-type 〈em〉T〈/em〉〈sub〉cp〈/sub〉 of 8-OEG〈sub〉2〈/sub〉 at high polymer concentrations (e.g., ≥10 mg∙mL〈sup〉−1〈/sup〉) was in the range of 37.5–42.5 °C. 8-OEG〈sub〉2〈/sub〉 showed a remarkable increase of hydrophilicity than PBLG-OEG〈sub〉4〈/sub〉 with the same amount of OEG units as well as linear shaped pendants. The 〈em〉T〈/em〉〈sub〉cp〈/sub〉 of OEGylated polypeptides increased by addition of NaI, yet it decreased upon addition of NaCl, NaBr, or KCl, which obeys the Hofmeister effect.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉We developed a new type of OEGylated polypeptides bearing Y-shaped pendants (8-OEG〈em〉x〈/em〉, 〈em〉x〈/em〉 = 2, 3) that showed a reversible LCST-type phase transition in a broad polymer concentration range and the LCST-type 〈em〉T〈/em〉〈sub〉cp〈/sub〉 can be tuned close to human body temperature. We have demonstrated that the water-solubility and LCST-type 〈em〉T〈/em〉〈sub〉cp〈/sub〉 can be improved by incorporation of Y-shaped and OEG pendants due to the increment of hydrophilicity.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001430571831231X-ga1.jpg" width="239" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 17 October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): María P. Fernández-Ronco, Rudolf Hufenus, Manfred Heuberger〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Melt-polymer processing is conventionally employed for thermoplastic polymeric materials. The rheological behaviour of the polymer is then of critical importance to correctly accomplish the process. The effect of pressurized fluid additives (PFA), such as CO〈sub〉2〈/sub〉 and N〈sub〉2〈/sub〉, has been investigated in this work to determine the extension of their beneficial plasticization effect on PLA. 〈em〉In-line〈/em〉 measurements performed by a custom-designed slit-die rheometer were conducted at different temperatures and PFA concentrations, and the viscosity values of PLA/PFA mixtures were experimentally determined and compared to those obtained when adding a commercial plasticizer, acetyltributylcitrate (ATBC), to PLA. Our results suggested that a twofold reduction of PLA viscosity is achievable using addition of 2.65 wt% pressurized CO〈sub〉2〈/sub〉 respect to similar contents of ATBC. Furthermore, a decrease of 10 °C of the processing temperature could be attained when adding 1.70 wt% of CO〈sub〉2〈/sub〉. This work aims at shedding light on the rheological behaviour that PLA experiences during assisted-melt extrusion processing, and on how more favourable energetic processing could be achieved by lowering temperature, if the appropriate type and concentration of PFA is employed during processing.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718312734-ga1.jpg" width="318" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 11 October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Abdalla Abdal-hay, Mahmoud Agour, Yu-Kyoung Kim, Min-Ho Lee, Mohamed K. Hassan, H. Abu El-Ainin, Abdel Salam Hamdy, Sašo Ivanovski〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study aimed to design an adhesive biodegradable polymer layer on the surface of titanium (Ti) implants for enhanced surface bioactivity. To this end, a coating of magnesium-particles doped biodegradable polyurethane (PU) was introduced as a composite layer on Ti surfaces using a simple spin coating technique. The coating’s performance and characteristics were investigated in terms of the surface topography, composition, surface roughness, wettability, adhesion and electrochemical behavior of composite coatings on untreated (polished) and alkaline treated Ti substrates. Interestingly, the Ti samples coated with the composite layers showed superior corrosion resistance compared to the uncoated samples. Additionally, the coating on alkali-treated Ti surfaces demonstrated enhanced adhesion (5B, measured by cross-cut test) compared to the coating on untreated Ti (1B), indicating the vital role of the alkaline-treatment step. A composite thin layer coated on alkaline-treated Ti enhanced osteoblastic-like (MC3T3-E1) cellular adhesion and cell proliferation and was found to support osteoblastic differentiation compared to uncoated alkaline-treated Ti. Surface modification of alkaline-treated Ti with a biodegradable Mg-particles/PU thin layer appears to be a promising strategy for developing surface bioactivity of orthopedic devices.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718314101-ga1.jpg" width="495" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Hui Liu, Zhengfeng Ma, Wufang Yang, Xiaowei Pei, Feng Zhou〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this paper, using one-step method of sub-surface initiated atom transfer radical polymerization (SSI-ATRP), the novel polymer brushes accompanied with structured surface were prepared on the resin base. Compared with the traditional surface initiated atom transfer radical polymerization (SI-ATRP) method, either surface chemical composition or topography was obtained through SSI-ATRP synchronously. Besides, we found that the structured polymers brush interface had better stability and long-term synergistic antifouling effect under seawater medium through soaking experiment and ocean field assay for long time. While, the bio-fouling assay results indicated that their excellent antifouling performances would be hindered by salt responsiveness of 3-sulfopropyl methacrylate potassium salt (SPMA) polymer brushes. Because it could be screened by high salt (e.g. Ca〈sup〉2+〈/sup〉 or Mg〈sup〉2+〈/sup〉) concentration, which decreased the hydration effect and further weakened the antifouling effect. The zwitterionic polymer (sulfobetaine methacrylate, SBMA), however, still showed excellent antifouling performances under high salt concentration since it produced stabilized ionic bonds with water molecules than those created from other hydrophilic materials. Given this, the structured zwitterionic and anionic copolymer brushes were fabricated as well, which realized the ideal stability and long-term antifouling effect under marine environment, ever high salt concentration medium. This research is of great value to marine antifouling in the long run and some other relevant fields.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718306694-fx1.jpg" width="279" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Alexander W. Bassett, Claire M. Breyta, Amy E. Honnig, Julia H. Reilly, Kayla R. Sweet, John J. La Scala, Joseph F. Stanzione〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Commercially available methacrylates often contain derivates of bisphenol A (BPA), a known human endocrine disruptor and petrochemical derived compound; therefore, alternatives are being investigated to increase sustainability and reduce toxicity. An asymmetric, bio-based bisphenol, VAC, was synthesized via an electrophilic aromatic condensation of vanillyl alcohol and cardanol. The alkyl side chain of VAC was subsequently hydrogenated to yield VAHC to determine the effects of side chain unsaturation on material properties. These bisphenols were methacrylated to prepare VACDM and VAHCDM, blended with a reactive diluent, cured, and compared to BPA dimethacrylate (BPADM), bio-based bisguaiacol dimethacrylate (BGDM), and a commercial BPA based vinyl ester (VE828). Resins containing VACDM and VAHCDM have reduced viscosities relative to BGDM and both BPA-based dimethacrylates, and the unsaturation on the side chain was shown to provide further reduced viscosities. Cured resins with VACDM and VAHCDM exhibit directly comparable thermal stability in both inert and oxidative environments, and decreased glass-transition temperatures due to increased aliphatic character relative to BPA-based resins. The toughness of the thermosets comprised of the bio-based bisphenols were greater than that of BPADM, where the alkyl substituent was shown to impart toughness into the network, yet the level of side chain saturation shows minimal effect on fracture toughness.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718321347-ga1.jpg" width="431" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Lin Zhang, Liang Zhao, Ying Ling, Haoyu Tang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉OEGylated homopolypeptide (i.e., P(Azo-S-OEG〈sub〉7〈/sub〉)) bearing azobenzene, thioether spacers, and oligo(ethylene glycol) OEG tails were prepared via a copper-mediated 1,3-dipolar cycloaddition. P(Azo-S-OEG〈sub〉7〈/sub〉) showed an upper critical solution temperature (UCST)-type thermo-, light-, and oxidation-responsive in ethanol/water solvent mixtures. The UCST-type cloud point temperature (〈em〉T〈/em〉〈sub〉cp〈/sub〉) decreased after UV irradiation and it increased after visible light irradiation due to the 〈em〉trans〈/em〉-〈em〉cis〈/em〉 isomerization of azobenzene moieties. P(Azo-S-OEG〈sub〉7〈/sub〉) can be readily oxidized in the presence of H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉, yielding P(Azo-S〈sup〉OX〈/sup〉-OEG〈sub〉7〈/sub〉) with sulfone or sulfoxide spacers. P(Azo-S〈sup〉OX〈/sup〉-OEG〈sub〉7〈/sub〉) showed an increase of UCST-type 〈em〉T〈/em〉〈sub〉cp〈/sub〉 after UV irradiation and the 〈em〉T〈/em〉〈sub〉cp〈/sub〉 decreased after visible light irradiation, which is an opposite trend to the UCST-type phase behavior of P(Azo-S-OEG〈sub〉7〈/sub〉) as well as previous report. P(Azo-S-OEG〈sub〉7〈/sub〉) showed poor water-solubility, yet it underwent H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 induced solution phase transition yielding P(Azo-S〈sup〉OX〈/sup〉-OEG〈sub〉7〈/sub〉) with lower critical solution temperature (LCST)-type phase behavior in water. The P(Azo-S〈sup〉OX〈/sup〉-OEG〈sub〉7〈/sub〉) aqueous solutions showed a decrease of LCST-type 〈em〉T〈/em〉〈sub〉cp〈/sub〉 after UV irradiation and consequently 〈em〉T〈/em〉〈sub〉cp〈/sub〉 decreased after visible light irradiation.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉We report the preparation and stimuli-responsive property of a thermo-, light-, and oxidation-responsive homopolypeptide bearing azobenzene, thioether spacers, and oligo(ethylene glycol) tails. After oxidation, the polypeptide showed unusual light-tunable thermoresponsive behaviors namely the UCST-type 〈em〉T〈/em〉〈sub〉cp〈/sub〉 increased while the LCST-type 〈em〉T〈/em〉〈sub〉cp〈/sub〉 decreased after UV light irradiation.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718320500-ga1.jpg" width="246" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Zhenyu Cui, Wei Li, Haiyi Zeng, Xiuxiu Tang, Jing Zhang, Shuhao Qin, Na Han, Jianxin Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, thermally induced phase separation (TIPS) method was adopted to manufacture polyvinylidene fluoride (PVDF) blend hollow fiber microfiltration membrane with tenon-connection structure, which is used to fasten in Chinese traditional building by the stronger friction between rabbet and mortise, for water treatment by blending polyvinyl butyral (PVB). In this microstructure formation process, the distribution of PVB within the matrix and its regulatory role were investigated. Especially, the comprehensive effect of rabbeting and PVB adhesion on strength (The maximum breaking strength reached 17.08 MPa) was discussed. The results showed that a suitable PVB will markedly reduce the thickness of skin-layer close to the outside surface even for the solid-liquid (S-L) phase separation while the excessive PVB result in a thick skin-layer. Besides the strength, PVB markedly improved the hydrophilicity and permeability of the membrane. The breaking strength is more than 8 MPa, the maximum pure water flux is as high as 929.23 L m〈sup〉−2〈/sup〉 h〈sup〉−1〈/sup〉 and the rejection rate of carbon particles is nearly 100% even the polymer content is only 22%. In addition, the membrane showed a β-phase and an improved anti-fouling capacity. The investigation presented a simple way to regulate microstructure, enhance mechanical strength, flux and anti-fouling capacity of the membrane via the TIPS process for water treatment.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718316653-ga1.jpg" width="267" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Peter T.M. Albers, Stefan P.W. Govers, Jozua Laven, Leendert G.J. van der Ven, Rolf A.T.M. van Benthem, Gijsbertus de With, A. Catarina C. Esteves〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Bio-lubricated surfaces found in nature have inspired the design of low friction polymer coatings for biomedical applications. This work presents a systematic study of the relation between the network structure parameters and the macroscopic friction properties of highly lubricious dual hydrophobic/hydrophilic polyurethane (PU) coatings in an aqueous environment. Chemically cross-linked PU coatings were prepared by adding poly(ethylene glycol) mono-methyl ether (mPEG) as hydrophilic dangling chains, or poly(ethylene glycol) (PEG)-diol as hydrophilic elastically active network chains, to poly(propylene glycol) (PPG)-PU coating formulations. The friction behaviour of the water swollen coatings was measured using a custom-made water immersed tribology setup. Addition of the PEG segments or mPEG dangling chains to hydrophobic PPG coatings greatly enhances the lubricious properties of the coatings. These dual hydrophobic/hydrophilic diol PU network exhibit a surface with a lower coefficient of friction compared to reference coatings from either individual precursors, demonstrating a large synergistic effect between the hydrophobic PPG and the hydrophilic PEG in the coatings. Based on network structure and surface chain considerations it is hypothesized that the existence of a thin and softer hydrated surface layer on top of a less hydrated, more rigid, coating bulk layer gives rise to the observed enhanced lubricious properties, hereby mimicking to some extent bio-lubricated systems, such as cartilage.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718317014-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 110〈/p〉 〈p〉Author(s): Shuzhen Ni, Baobin Wang, Hui Zhang, Yongchao Zhang, Zhulan Liu, Weibing Wu, Huining Xiao, Hongqi Dai〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉An effective and facile approach to functionalize starch was developed using glyoxal and ammonium zirconium carbonate (AZC) as the co-crosslinking agents. The resultant starch was characterized for chemical structure, surface morphology, thermal stability, optical and hydrophobic properties and mechanical strength. 〈sup〉1〈/sup〉H and 〈sup〉13〈/sup〉C nuclear magnetic resonance (NMR) spectrum confirmed the successful Schiff-base reaction on the starch. X-ray diffraction (XRD) showed that the low glyoxal dosage had an adverse impact on the degree of crystallinity. Thermalgravimetric (TG) results revealed the weakened thermal stability at the initial decomposition process and enhanced thermal stability above the maximum degradation temperature. A smoother surface on the resultant film was observed by scanning electron microscopy (SEM) after the addition of glyoxal. Significantly, enhanced mechanical and hydrophobic properties as well as ultraviolet (UV) blocking capacity of the resultant starch film were achieved at 5% (wt) glyoxal and 5% (wt) AZC content. Improved hydrophobic property and mechanical strength were also obtained even with very low dosages of glyoxal (0.5%, wt) and AZC (2.5%, wt). This new type of starch with double functionalities (i.e., hydrophobic and UV blocking capacity) provides beneficial implications for improving the performance of starch-based materials.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718319670-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 110〈/p〉 〈p〉Author(s): Christopher Stubbs, Thomas R Congdon, Matthew I. Gibson〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Antifreeze, ice binding and ice nucleating proteins modulate the formation and growth of ice in biological systems, enabling extremophiles to survive in sub-zero temperatures. A common feature is their rigidity, and segregated hydrophobic and hydrophilic domains. It has been demonstrated that increased hydrophobicity in rigid, facially amphipathic, synthetic polymers enhances ice recrystallisation inhibition (IRI) activity, but has not been evaluated in flexible systems. Here photochemical RAFT/MADIX polymerisation is used to obtain well-defined poly(〈em〉N〈/em〉-vinyl pyrrolidone), PVP, copolymers to probe the impact of hydrophobicity on ice recrystallisation inhibition in a fully flexible polymer system, to increase the understanding on how to mimic antifreeze proteins. It is observed that PVP homopolymers have only very weak, molecular weight dependent, IRI and that hydrophobic co-monomers give very modest changes in IRI, demonstrating that the spacial segregation of ‘philicities’ is crucial, and not just the overall hydrophobic content of the polymer. These results will help design the next generation of IRI active polymers for cryopreservation applications as well as aid our understanding of how biomacromolecules can inhibit ice growth.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718318676-ga1.jpg" width="363" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Ruiwen Chen, Sarah J. Benware, Sawyer D. Cawthern, Justin P. Cole, Jacob J. Lessard, Isabelle M. Crawford-Eng, Riya Saxena, Erik B. Berda〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We present the synthesis of poly(oxanorbornene imide) single-chain nanoparticles (SCNP) by intrachain radical polymerization of pendant methacryloyl units. Well-defined poly(oxanorbornene imide)s were first prepared 〈em〉via〈/em〉 ring-opening metathesis polymerization (ROMP) of methacryloyl-containing monomers. Handling and polymerizing these monomers requires some special care to prevent undesired premature reaction of the methacryloyl groups. Addition of AIBN to dilute solution of the ROMP polymers triggers intrachain radical polymerization of pendant methacryloyl groups, folding the linear polymers into SCNP. Characterization by NMR spectroscopy and SEC confirmed SCNP formation and revealed structure/property relationships related to methacryloyl pendent length and percent incorporation.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718321876-ga1.jpg" width="276" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Leyre Pérez-Álvarez, Leire Ruiz-Rubio, Iñigo Azua, Vanessa Benito, Ainhoa Bilbao, José Luis Vilas-Vilela〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Antibacterial coatings have been widely explored to inhibit biofilm formation in order to prevent post-implantation infections of biomedical devices. However, due to the complex mechanism of bacterial adhesion and proliferation, only the combination of different strategies can lead to higher antibacterial efficiency, especially in the initial stages. For this, layer by layer (LbL) assembly of hyaluronic acid (HA) and chitosan (CHI) was successfully developed onto activated surface of polyethylene terephthalate in order to obtain polyelectrolyte multilayers (PEMs) that combine adhesion resistance, contact killing properties and modulated releasing of antibacterial agents. PEMs showed high efficiency for loading of triclosan (TRI) and rifampicin (RIF). The release of these bactericides could be modulated by their sequential incorporation along the polysaccharide layers. HA/CHI multilayers inhibited 〈em〉E. coli〈/em〉 adhesion onto developed surfaces and when TRI and RIF were loaded in the coatings, better antibacterial activity was demonstrated. The possibility of acting as antibacterial reservoir added to the antibacterial properties of the polysaccharide layer make these multilayers promising materials as implants substrates.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718321311-ga1.jpg" width="299" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Xibo Yan, Veronica La Padula, Sabine Favre-Bonte, Julien Bernard〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Mannosylated macro chain transfer agents (MacroCTA) have been used for the RAFT emulsion polymerization of glycidyl methacrylate (GMA) to prepare a series of glyconanoparticles with different morphologies via polymerization-induced self assembly (PISA). Upon increase of PGMA block length and solids content, morphologies progressively evolved from spheres to large vesicles. The epoxide functions located in the core of the nanoparticles were exploited as convenient handles to cross-link the PGMA core and attach red emissive fluorescent tags. Thanks to the presence of multiple 〈em〉n〈/em〉-heptyl α-〈span〉d〈/span〉-mannose ligands on their shell, the glyconanoparticles strongly interacted with type 1 piliated 〈em〉Escherichia coli〈/em〉 leading to the formation of large bacterial clusters.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718322183-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Ville Hynninen, Pezhman Mohammadi, Wolfgang Wagermaier, Sami Hietala, Markus B. Linder, Olli Ikkala, Nonappa〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Methylcellulose/cellulose nanocrystal (MC/CNC) nanocomposite fibers showing high ductility and high modulus of toughness were prepared by a simple aqueous wet-spinning from corresponding nanocomposite hydrogels into ethanol coagulation bath followed by drying. The hydrogel MC aq. concentration was maintained at 1 wt-% while the CNC aq. loading was systematically varied in the range 0–3 wt-%. This approach resulted in MC/CNC fiber compositions from 25/75 wt-%/wt-% to 95/5 wt-%/wt-%. The optimal mechanical properties were achieved with the MC/CNC composition of 80/20 wt-%/wt-% allowing high strain (36.1%) and modulus of toughness (48.3 MJ/m〈sup〉3〈/sup〉), still keeping a high strength (190 MPa). Further, we demonstrate that the continuous spinning of MC/CNC fibers is potentially possible. The results indicate possibilities to spin MC-based highly ductile composite fibers from environmentally benign aqueous solvents.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718324960-ga1.jpg" width="460" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Jurong Lu, Xingcui Feng, Yihong Huan, Naiwu Chen, Renzhi Li, Wenyong Lai, Bing Liu, Deqing Gao, Wei Huang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A series of double-cable polymers 〈strong〉PFT-C〈sub〉4〈/sub〉-PDI〈/strong〉, 〈strong〉PFT-C〈sub〉6〈/sub〉-PDI〈/strong〉 and 〈strong〉PFT-C〈sub〉8〈/sub〉-PDI〈/strong〉, composed of the poly(fluorene-alt-thiophene) (PFT) backbone, the perylene diimide (PDI) pendants and the length-various (four-, six- and eight-carbon) covalent alkoxy linkers, were presented. The backbone polymer chain created the hole-transporting channel and the inner-chain aggregation of PDI units created the electron-transporting channel, but the aggregation became weaker along with the longer linker, as proven by the UV–Vis absorption and fluorescence quenching. The polymers were non-conducting, but functioned as efficient compatibilizers. The doping of the polymers induced the formation of the bi-continuous networks inside P3HT:PCBM blends, facilitated photo-generated exciton dissociation and charge transporting. 〈strong〉PFT-C〈sub〉4〈/sub〉-PDI〈/strong〉 more efficiently increased the absorption coefficient and the charge-carrier mobility of the P3HT:PCBM film. The power conversation efficiency (PCE) of the P3HT:PCBM bulk-heterojunction solar cells with 3 wt% 〈strong〉PFT-C〈sub〉4〈/sub〉-PDI〈/strong〉, 〈strong〉PFT-C〈sub〉6〈/sub〉-PDI〈/strong〉 and 〈strong〉PFT-C〈sub〉8〈/sub〉-PDI〈/strong〉 doping were improved by 16.9%, 9.2% and 8.0%, respectively, relative to the non-doped reference device.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718312801-ga1.jpg" width="420" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Sheng-Yaw Hsu, Sheng-Chi Lin, Jeng-An Wang, Tzu-Yu Cheng, Chih-Wen Lin, Yi-Hong Chen, De-Hao Tsai, Chen-Chi M. Ma〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, a facile synthetic approach was demonstrated for the preparation of graphene oxide (GO)-modified soluble polyimide (SPI) nanocomposites with enhanced mechanical properties. Firstly, a two-step method was employed to form SPI via polymerization of cycloaliphatic dianhydride (bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride) and aromatic diamine (2,2′-Bis[4-(4-aminophenoxy)phenyl]propane). Amino-substituted silsesquioxane (SQ) was used to conjugate with GO to form SQ-grafted graphene oxide (SQ@GO) and thermally-treated SQ@GO (TSQ@GO). Fourier-transformed infrared spectroscopy, 〈sup〉29〈/sup〉Si nuclear magnetic resonance spectroscopy, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectrometry were used complementarily for the study of the chemical structures of the prepared SQ@GO, TSQ@GO and SPI/TSQ@GO nanocomposite film (i.e., TSQ@GO in SPI matrix). Results show successful synthesis of SQ@GO, TSQ@GO and SPI/TSQ@GO nanocomposite film. With support of excellent dispersibility of TSQ@GO in SPI matrix, the tensile properties of SPI improved significantly via hybridization with TSQ@GO: tensile strength enhanced to 1.3X and elongation at break increased to 3 folds. This study demonstrated a prototype method for fabrication of pre-imidized SPI/TSQ@GO nanocomposite, which has shown the promise for moderate-temperature manufacture (below 200 °C) of emerging electronic applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718308413-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Chao Liu, Youming Li, Yi Hou〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Biomass nanomaterials based on aromatic ring monomers have broad application prospects in the fields of drug delivery, catalysis and environment. In this paper, based on the effective dissolution of commercial alkali lignin in imidazole ionic liquids, lignin nanospheres were rapidly prepared by adding anti-solvent of water. In the three imidazole ionic liquids (1-amyl-3-methylimidazolium acetate (C5mim][Ac]), 1-butyl-3methylimidazolium acetate ([Bmim][Ac]) and 1-ethyl-3-methylimidazolium acetate ([Emim][Ac])), lignin can dissolve well, and the dissolution rates are all 〉25%, which is much higher than other organic solvents. And the longer the alkyl chain in imidazole ring is, the lower the solubility of lignin is. The paper also studied the effects of lignin concentration, the addition rate of anti-solvent, stirring rate and pH on the size of lignin nanospheres. It was found that the lignin nanospheres prepared under suitable conditions have particle size in the range of 52–210 nm and have good stability for over two months. And, compared to other studied, the particle size of the nanospheres is much smaller and easier to control. Moreover, the quality of lignin nanospheres was elucidated by Fourier transform infrared spectroscopy (FT-IR), Gel permeation chromatography (GPC) and UV–vis spectroscopy (UV–Vis) measurements which found the molecular weight of lignin nanospheres was slightly lower the raw alkali lignin, and the main structure of the aromatic ring of lignin is preserved in the process of preparation of the nanospheres by ILs. The method of preparing lignin nanosphere from lignin-ionic liquids solution with water as anti-solvent is simple, rapid and environmentally friendly, and provides an efficient and feasible path for the high value utilization of lignin.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718320299-ga1.jpg" width="265" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 110〈/p〉 〈p〉Author(s): 〈/p〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Tiphaine Messin, Stéphane Marais, Nadège Follain, Corinne Chappey, Alain Guinault, Guillaume Miquelard-Garnier, Nicolas Delpouve, Valérie Gaucher, Cyrille Sollogoub〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A multilayer film composed of alternating layers of polycarbonate (PC) and poly(m-xylene adipamide) (MXD6) was elaborated by using an innovative multilayer coextrusion process. Quasi-continuous thin MXD6 layers (nanolayers) alternating with PC layers were successfully obtained. The PC/MXD6 multilayer film showed a confining effect of MXD6 exerted by PC layers leading to an improvement of barrier properties despite a low degree of crystallinity (X〈sub〉c〈/sub〉 〈 10 wt%). In order to further improve the barrier performances, crystallization treatments induced by water and by heating were then applied on the multilayer film and allowed reaching around 30 wt% of crystallinity in MXD6 layers. To decouple crystallization and geometrical constraint effects on the barrier properties in the multilayer films, the two treatments were also applied on MXD6 films. Surprisingly, despite an increase of the degree of crystallinity from 6 to 26%, water crystallization did not permit to improve gas barrier performances of the MXD6 film nor into the PC/MXD6 multilayer film. On the other hand, thermal crystallization of MXD6 in the multilayer film seems to be a more efficient route to strongly decrease the gas and moisture permeability, up to 75% for nitrogen, 58% for oxygen, 84% for carbon dioxide and 43% for water.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718310097-ga1.jpg" width="303" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Małgorzata Burek, Klaudia Kubic, Izabela Nabiałczyk, Sylwia Waśkiewicz, Ilona Wandzik〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Five acid-labile diacetal crosslinkers containing disaccharide trehalose were synthesized. Effects of different substituents on aromatic ring on hydrolysis kinetics were compared using time-dependent 〈sup〉1〈/sup〉H NMR spectroscopy. A model protein (bovine serum albumin, BSA) was physically entrapped within bulk acrylamide-type hydrogels during redox-initiated free-radical polymerization. Under acidic conditions, hydrogel degradation occurred 〈em〉via〈/em〉 cleavage of diacetal crosslinks to aqueous-soluble polymeric chains and free trehalose. The relationship between hydrogel degradation and protein release at around physiological pHs was studied. It was shown that selecting an appropriate crosslinker structure and main monomer type allows the tailoring of protein release profiles.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718318251-ga1.jpg" width="395" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Antigoni Theodoratou, Luca Costa, Laurent Bonnet, Christophe Blanc, Vincent Lapinte, Pascal Etienne, Pierre-Emmanuel Milhiet, Jean-Jacques Robin, Julian Oberdisse, Joël Chopineau, Anne Aubert-Pouëssel〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A comprehensive characterization of physical-chemical properties and biological interactions of ca. 200-nm-thick hybrid films based on silylated (inorganic part) castor oil (organic part) is proposed. A series of such nanofilms was fabricated and cross-linked by a sol-gel procedure, and their properties such as hydrophilicity, hardness and water vapour transmission rate were systematically studied as a function of the ratio of silylated agent to castor oil. It was found that the nanofilms have contact angles always below 90°, tunable Young modulus and hardness in the MPa range. Moreover, their water vapour transmission rates are increased by decreasing the silica ratio. The protein adsorption and cytocompatibility were evaluated using model proteins and cells. The adsorption of the proteins bovine serum albumin (BSA) and lysozyme was characterized using a quartz crystal microbalance in energy dissipation mode (QCM-D), and atomic force microscopy (AFM). The combination of the latter provided evidence for the different affinities of the proteins with the films. It was found that BSA and lysozyme form rigid layers on the surface with surface coverage close to 30%, and that both protein layers decrease their thickness after their dehydration. Finally, cell culture experiments exhibited a good viability of the fibroblasts compared to ultra-low adhesion surfaces, which makes them potential candidates for biomedical applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718317038-ga1.jpg" width="380" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Alexandra Langford, Clement Matthew Chan, Steven Pratt, Christopher J. Garvey, Bronwyn Laycock〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The crystallisation of a range of as-produced poly(3-hydroxybutyrate-〈em〉co〈/em〉-3-hydroxyvalerate) copolymer blends from a mixed culture polyhydroxyalkanoate production process, with low (15%), high (82%) and intermediate (62% and 50%) average 3-hydroxyvalerate (3HV) contents, was studied at different temperatures using polarised optical microscopy, differential scanning calorimetry and X-ray crystallography. The low-3HV content material had narrow compositional distribution and crystallised in the typical highly regular banded spherulite morphology, while the other materials displayed varying degrees of interpenetrating crystallisation of separate crystal phases comprising either the 3HV or 3-hydroxybutyrate (3HB) crystal lattice structure. Because of the differing and competing crystallisation kinetics of these phases coupled with diffusion effects, there was a very strong influence of crystallisation temperature on the resulting morphology. Thus manipulation of the final material properties of such copolymeric materials is dependent on understanding these effects and controlling their processing and crystallisation temperatures and conditions.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718319943-ga1.jpg" width="465" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: April 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 113〈/p〉 〈p〉Author(s): Laura Aliotta, Patrizia Cinelli, Maria Beatrice Coltelli, Andrea Lazzeri〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉In recent years the plastics market is moving towards biopolymers and the increasing demand of not oil derived products has led to the development of new composites deriving from renewable resources. Undoubtedly the most studied biopolymer is poly(lactic acid) (PLA). This work is focused on the use of rigid inorganic fillers as toughening agents, in order to obtain a rigid and tough PLA composite and enlarge the range of applications for PLA. The rigid filler toughening mechanism has been studied and, as toughening agent, commercial calcium carbonate particles with and without surface treatment have been compared. Because of the PLA intrinsic fragility, a plasticization of the matrix was necessary to favor the plastic deformation and consequently the stretching of interparticle ligaments.〈/p〉 〈p〉In particular, in this work, the effect of both the plasticizer and the particles surface treatment with stearic acid were analyzed. It has been observed that the surface treatment alone is not able to provide a significant increase in the PLA toughness. In fact, the particle surface coating favors the particles dispersion and reduces the adhesion with the matrix, favoring debonding, but the plastic deformation of the matrix around the voids is not significant without a plasticizer addition. Moreover, the best impact performance and ductility were achieved with the surface treated calcium carbonate, in agreement with a more controlled growth of voids formation during material solicitation, as resulting from tensile dilatometric tests.〈/p〉 〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718318536-ga1.jpg" width="292" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Marcin Masłowski, Justyna Miedzianowska, Krzysztof Strzelec〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Unmodified and silanized cereal straw and two types of silica (hydrophilic and hydrophobic) were chosen to produce functional hybrid fillers. The method of mechanical grinding with simultaneous mixing was used to combine the applied compounds. The obtained materials were subjected to thermal, morphological and dispersive analysis as well as surface wettability. The introduction of an inorganic phase into the lignocellulosic material improved the thermal stability of the systems. A new functional additive with significantly lower polarity was obtained by combining hydrophobic silica and silanized straw. The prepared organic-inorganic hybrid materials were used as fillers of natural rubber (NR). The determined processing and usage properties indicate the beneficial effect of newly formed additives on the parameters of crosslinking, rheometry characteristics and aging resistance. In addition, organic-inorganic hybrid additives are capable of producing a more developed filler structure in the elastomer matrix, which results in an increase in crosslinking density and mechanical strength of the vulcanizates. The presence of the straw-silica hybrid system has a significant influence on the barrier properties and flammability of the NR vulcanizates.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718320834-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Juliana Anggono, Ágnes Elvira Farkas, András Bartos, János Móczó, Antoni, Hariyati Purwaningsih, Béla Pukánszky〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Polypropylene composites were prepared from sugarcane bagasse fibers by extrusion and injection molding. Wood flour was used as reference filler in the study. The fiber content of the composites changed between 0 and 30 wt% in 5 wt% steps. Maleated polypropylene was used as coupling agent to improve interfacial adhesion. Mechanical properties were characterized by tensile and fracture testing, while local deformation processes were followed by acoustic emission and instrumented impact testing, as well as by the analysis of scanning electron micrographs. The results showed that sugarcane bagasse fibers reinforce polypropylene similarly to other natural fibers. They increases stiffness, but decrease tensile yield stress, tensile strength and deformability. Increased interfacial adhesion leads to the considerable improvement of reinforcement. Bagasse fiber and wood flour filled composites have very similar properties. The impact resistance of the composites increased in the presence of both fibers compared to the neat matrix. Debonding is the dominating process in the absence of the coupling agent, while mainly fiber fracture occurs in its presence. Increased plastic deformation after debonding results in slightly improved impact resistance.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718320317-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Nejib Kasmi, Niki Poulopoulou, Zoi Terzopoulou, Dimitrios G. Papageorgiou, Dimitrios N. Bikiaris, George Z. Papageorgiou〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Poly(1,4-cyclohexane dimethylene 2,5-furandicarboxylate) (PCHDMF) is a sustainable thermoplastic that can be prepared from renewable resources with potential uses as a replacement for its terephthalate (PCHDMT) and naphthalate (PCHDMN) analogues. A detailed study has been undertaken to assess its thermal behavior and chemical/structural characteristics, in comparison to its counterparts. The melting temperature of PCHDMF was observed at 〈em〉T〈/em〉〈sub〉m〈/sub〉 = 264.5 °C, the glass transition was obtained at 77 °C and the cold crystallization temperature was seen at 121 °C. The melting of the polymers was studied under a variety of conditions and all samples displayed the characteristic melting-recrystallization-remelting behavior. Isothermal and dynamic crystallization tests revealed that PCHDMF crystallizes at faster rates than its analogues, while the equilibrium melting point of PCHDMF was established at 300 °C. The enthalpy of fusion values for the polyesters were found Δ〈em〉H〈/em〉〈sub〉m〈/sub〉 = 137 J/g for PCHDMF, Δ〈em〉H〈/em〉〈sub〉m〈/sub〉 = 108 J/g for PCHDMT, Δ〈em〉H〈/em〉〈sub〉m〈/sub〉 = 119 J/g for PCHDMN. Using the Lauritzen-Hoffman analysis of spherulite growth rates, larger 〈em〉K〈/em〉〈sub〉g〈/sub〉 values were found for PCHDMF, due to its less flexible structure.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001430571831680X-ga1.jpg" width="247" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Swarup Ghosh, Thi Nhan Nguyen, Thuy Tran Thi, Esteban Mejía〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Herein we re-evaluate the synthesis of Poly(ε-caprolactone) (PCL) by ring-opening polymerization (ROP) using simple dialkylmagnesium compounds as catalysts. This old reaction has been never studied thoroughly before and a consensus on the intervening mechanism is lacking, being an anionic pathway proposed in the classic literature. In our hands, all tested catalysts exhibit high efficiency and complete conversion was achieved within a few hours with high yield and high number-average molecular weight (〈em〉M〈/em〉〈sub〉n〈/sub〉) in a living fashion. Moreover, kinetic studies revealed that the ROP of ε-CL has a first order dependency on monomer (ε-CL) as well as catalyst concentration. Furthermore, mechanistic studies of the ROP demonstrated that the reaction follows a coordination-insertion mechanism where the alkyl group initiates the polymerization and is incorporated as one of the terminal groups in the polymer chain.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718320913-ga1.jpg" width="254" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Bora Onat, Sinem Ulusan, Sreeparna Banerjee, Irem Erel-Goktepe〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We report the surface modification of chitosan/poly(ethylene glycol) (chitosan/PEG) hydrogel materials via layer-by-layer (LbL) technique using stimuli-responsive polymers. Water-soluble complexes of Tannic Acid (TA) and a broad-spectrum antibiotic, Ciprofloxacin (Cipro) were prepared and co-assembled at the surface of Chitosan/PEG hydrogels with poly(N-vinyl caprolactam) (PVCL). Compared to the bare hydrogels, the surface spreading and proliferation of human fibroblasts were significantly enhanced on precast hydrogels coated with TA-Cipro/PVCL multilayers. LbL coating also provided enhanced Cipro release from the hydrogel surface at 37 °C compared to bare hydrogels. TA-Cipro/PVCL coated hydrogels showed antibacterial activity through chitosan and temperature-induced release of Cipro from multilayers. Chitosan and Cipro showed a coordinated antibacterial effect on 〈em〉Eschericia coli〈/em〉 and 〈em〉Bacillus cereus〈/em〉, reducing their minimum inhibitory concentration (MIC). This effect was more pronounced on 〈em〉B. cereus〈/em〉. LbL modification of chitosan-based hydrogels using stimuli responsive polymers can be advantageous for bringing multiple functionalities to these materials without sacrificing their intrinsic properties such as antibacterial activity and biocompatibility. Such LbL-coated hydrogels hold promise in wound treatment as they may promote fibroblast proliferation and skin tissue regeneration.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718316227-ga1.jpg" width="277" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Zhipeng Hou, Wei Zhang, Jing Guo, Zhangpei Chen, Jianshe Hu, Liqun Yang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Poly(trimethylene carbonate-co-2, 2′-dimethyltrimethylene carbonate) [P(TMC-co-DTC)] with a molecular weight of about 150 kDa and different copolymer composition were synthesized by ring opening copolymerization of trimethylene carbonate (TMC) and 2, 2′-dimethyltrimethylene carbonate (DTC), using stannous octoate [Sn(Oct)〈sub〉2〈/sub〉] as catalyst. The results of thermal properties investigation showed that the glass transition temperature (〈em〉T〈/em〉〈sub〉g〈/sub〉) of P(TMC-co-DTC) elevated with the increase of DTC segments in the composition. Furthermore, the acquired P(TMC-co-DTC) presented high thermal stability and good flexibility. The 〈em〉in vitro〈/em〉 enzymatic degradation of P(TMC-co-DTC) was carried out in the lipase solutions (from 〈em〉Thermomyces lanuginosus〈/em〉, ≥100,000 U/g). The results showed that P(TMC-co-DTC) exhibited much better form-stability and lower degradation rate than poly(trimethylene carbonate) (PTMC),and the higher the DTC content, the lower the degradation rate. Hence, the methylated-functionalization caused by the introduction of DTC segments was an effective strategy to control the degradation behavior of PTMC.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718317828-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Abhishek Gupta, Marek Kowalczuk, Wayne Heaselgrave, Stephen T. Britland, Claire Martin, Iza Radecka〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Wound treatment has increased in importance in the wound care sector due to the pervasiveness of chronic wounds in the high-risk population including, but not limited to, geriatric population, immunocompromised and obese patients. Furthermore, the number of people diagnosed with diabetes is rapidly growing. According to the World Health Organization (WHO), the global diabetic occurrence has increased from 4.7% in 1980 to 8.5% in 2014. As diabetes becomes a common medical condition, it has also become one of the major causes of chronic wounds which require specialised care to address patients’ unique needs. Wound dressings play a vital role in the wound healing process as they protect the wound site from the external environment. They are also capable of interacting with the wound bed in order to facilitate and accelerate the healing process. Advanced dressings such as hydrogels are designed to maintain a moist environment at the site of application and due to high water content are ideal candidates for wound management. Hydrogels can be used for both exudating or dry necrotic wounds. Additionally, hydrogels also demonstrate other unique features such as softness, malleability and biocompatibility. Nowadays, advanced wound care products make up around $7.1 billion of the global market and their production is growing at an annual rate of 8.3% with the market projected to be worth $12.5 billion by 2022.〈/p〉 〈p〉The presented review focuses on novel hydrogel wound dressings, their main characteristics and their wound management applications. It also describes recent methodologies used for their production and the future potential developments.〈/p〉 〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718318317-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Yin Li, Maarten Vergaelen, Ella Schoolaert, Richard Hoogenboom, Karen De Clerck〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, benzophenone was introduced onto partially hydrolyzed poly(2-ethyl-2-oxazoline) (PEtOx-PEI) to prepare a poly(2-ethyl-2-oxazoline)-benzophenone (PEtOx-BP) copolymer, which was used to produce water stable nanofibers 〈em〉via〈/em〉 aqueous electrospinning and photocrosslinking. Three different ultraviolet (UV) irradiation methods, 〈em〉i.e.〈/em〉 pre-crosslinking before electrospinning, in-situ crosslinking during electrospinning and post-crosslinking after electrospinning, were used to prepare crosslinked nanofibers. The influence of UV-irradiation at these different stages of the nanofiber production process was investigated in terms of alterations in viscosity, nanofiber morphology and water stability of the fibers. It was shown that pre-crosslinking the polymer solutions had a great influence on the solution viscosity which could both positively or negatively alter the stability of the electrospinning process. Whereas the strategy of crosslinking nanofibers during the production process did not lead to uniform nor water-stable nanofibers, the pre-crosslinking and post-crosslinking strategies greatly increased the water stability of the nanofibers. In both techniques the crosslinking density and therefore water solubility can be easily tuned by manipulating the polymer concentration, UV-irradiation time and membrane thickness. Complete insolubility, 〈em〉i.e.〈/em〉 the formation of crosslinked networks, was achieved by the post-crosslinking strategy. This work provides straightforward methods to increase the water stability of the PEtOx nanofibers, which will definitely be of great value to biomedical applications such as drug delivery and tissue engineering.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718322031-ga1.jpg" width="449" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Bekir Satilmis, Tamer Uyar〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Polymers of intrinsic microporosity (PIMs) are increasingly recognized as a potential membrane material for adsorption and separation applications due to their permanent porosity and solution processability. PIM-2 can be produced using commercially available 5,5′,6,6′-Tetrahydroxy-3,3,3′,3′-tetramethyl-1,1′-spirobisindane and decafluorobiphenyl monomers in the powder form. It possesses considerable amount of fluorine in the polymer backbone and this feature could provide significant hydrophobicity to polymer. This research aims to investigate the fabrication of self-standing PIM-2 fibrous membranes by electrospinning method to introduce a useful material for adsorption applications. Electrospinning was performed using tetrachloroethane as a solvent and bead-free, uniform fibers were produced as confirmed by SEM imaging. Average fiber diameter was calculated as 5.5 ± 1.5 μm for a self-standing fibrous membrane of PIM-2. Structural characterization was conducted using FT-IR, NMR and XPS spectroscopies showing the purity of pristine powder and fibrous membrane of PIM-2. Thermal stability of PIM-2 fibrous membrane was investigated using TGA and it shows no discernible weight loss below 450 °C. The porosity of fibrous membrane was investigated by N〈sub〉2〈/sub〉 adsorption/desorption measurements that indicates significant microporosity with ∼600 m〈sup〉2〈/sup〉 g〈sup〉−1〈/sup〉 BET surface area. In addition, the hydrophobicity of PIM-2 was tested by water contact angle measurements, showing 155 ± 6° WCA, indicating superhydrophobicity owing to rough surface and high fluorine content. Consequently, the combination of straightforward synthesis, solution processability, high thermal stability, high surface area, and superhydrophobicity makes PIM-2 a promising candidate for adsorption applications. Therefore, it was successfully employed in organic and oil adsorption. Fibrous membranes of PIM-2 has shown up to 2200 ± 100% and 1900 ± 100% weight gain after in contact with silicon oil and DMSO respectively. In addition, dense membrane of PIM-2 was prepared by solvent casting method and the uptake ability was compared with fibrous membrane showing that fibrous form is more convenient for liquid adsorption applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718319335-ga1.jpg" width="337" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Priyanka Chaudhary, Dheeraj Kumar Maurya, Samiksha Sikarwar, B.C. Yadav, G.I. Dzhardimalieva, Rajiv Prakash〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present paper reports the polymer matrix of Ni(NO〈sub〉3〈/sub〉)〈sub〉2〈/sub〉(AAm)〈sub〉4〈/sub〉·2H〈sub〉2〈/sub〉O thin film as an electrical and opto-electronic humidity sensor. For this purpose, films were prepared by spin-coating method to investigate the adsorption/desorption of humidity at room ambient. The sensing element was investigated through X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and UV–Vis absorption techniques. XRD exhibited the crystalline nature of the nanomaterial thin film and evaluated average crystallite size was 30 nm. SEM showed highly porous nanostructures of different size distributed throughout the film. Energy band-gap of the film was estimated as 4.034 eV. TEM image showed the nanostructures with the average grain size of 4-21 nm and SAED confirmed the crystalline nature of the material. The film was further employed for two different modes of humidity sensing i.e., impedance-based electrical humidity measurement and transmission based opto-electronic humidity measurement which gave a maximum average sensitivity of 37.79 MΩ/%RH and 1.31 µW/%RH respectively at room temperature.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718318457-ga1.jpg" width="330" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Fiona C. Binks, Gabriel Cavalli, Michael Henningsen, Brendan J. Howlin, Ian Hamerton〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A series of adducts were prepared based on the reaction of 1-ethyl-3-methylimidazolium acetate and benzaldehyde in various stoichiometries (from equimolar reaction to benzaldehyde in 10-fold excess) and the resulting adducts were characterized using nuclear magnetic resonance spectroscopy (〈sup〉1〈/sup〉H, 〈sup〉13〈/sup〉C, DEPT, and HQSC experiments). Differential scanning calorimetry was used to examine the initiating behaviour of the adducts towards mono- and di-functional epoxy resins and the data were used to determine kinetic parameters for the polymerization. The lower temperature peak, due to carbene formation, is sensitive to adduct concentration; the residual ionic liquid in the adduct mixture contributes towards the initiation of the curing reaction. When a monofunctional epoxy and the 1:1 adduct was subjected to a 2-week period of storage at room temperature and sub-zero temperatures in the freezer, the profiles of the thermograms for the frozen samples do not change considerably over the storage period and the formulation retains a light yellow colour (rather than the viscous, dark red appearance of the formulation stored at room temperature).〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718318408-ga1.jpg" width="305" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Chulu Zhou, Yang Wang, Lanxiao Zhao, Zhizhou Liu, Jianhua Cheng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉We present a new cyclooctene monomer with abundant biorenewable limonene oxide as side group via simple esterification, which could be polymerized by ring-opening metathesis polymerization (ROMP) using Hoveyda-Grubbs second-generation catalyst (〈strong〉H2〈/strong〉) to afford polymer with remarkably high head-to-tail regioregularity and high 〈em〉trans〈/em〉-stereoregularity, as well as precisely placed ether branches on every eighth backbone carbon. Due to the presence of easily functional oxirane in limonene oxide side chain, the polymer can be efficiently modified by thiol, or dibutyl phosphate that shows impart flame-resistant property, even bearing pendent cyclic carbonate groups by CO〈sub〉2〈/sub〉 insertion catalyzed by tetrabutylammonium bromide. In all cases, the main chains of the polymer remain intact. Differential scanning calorimetry (DSC), thermal gravimetric analyzer (TGA) and the microscale combustion calorimeter test (MCC) were used to study the thermal properties and flame retardancy.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉A new cyclooctene monomer with abundant biorenewable limonene oxide as side group which could be polymerised by regio-/stereoselective ring-opening metathesis polymerization (ROMP) using Hoveyda-Grubbs second-generation catalyst (〈strong〉H2〈/strong〉). Moreover, the oxiane in limonene oxide side chain could be efficiently modified by many functional group.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001430571832007X-ga1.jpg" width="347" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 16 October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): J. Zhang, J. Lalevée, F. Morlet-Savary, B. Graff, P. Xiao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Diamino-anthraquinone derivatives [1,4-bis(isopropylamino)anthraquinone (SB36), 1-amino-4-anilinoanthraquinone (SB68), and 1,4-bis(p-tolylamino)anthraquinone (SG3)] exhibit absorption maxima in red light wavelength range and demonstrate broad ground state light absorption from ultraviolet to infrared light. When combined with coinitiators (〈em〉e.g.〈/em〉 iodonium salt), SB36-based photoinitiating systems exhibit the highest photoinitiation efficiency among all the studied diamino-anthraquinone derivative-based combinations for both cationic and free radical photopolymerization upon exposure to a red LED bulb. And SB36-based systems even demonstrate higher photoinitiating ability for free radical photopolymerization than that of previously studied 1,4-bis(pentylamino)anthraquinone (〈em〉i.e.〈/em〉 oil blue N)-based systems. In contrast, SG3-based photoinitiating systems show the lowest photoinitiation efficiency especially for free radical photopolymerization. Interestingly, the SB36/iodonium salt/N-vinylcarbazole system is a capable multicolor photoinitiating system able to initiate both cationic and free radical photopolymerization under the irradiation of UV to red LED bulbs and IR lamp. The photochemical mechanism associated with the production of cations and radicals from the diamino-anthraquinone derivative-based photoinitiating systems are investigated using steady state photolysis, fluorescence, laser flash photolysis, and electron spin resonance spin-trapping techniques.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718314149-ga1.jpg" width="324" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 15 October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): XuYing Zheng, ShiYang Song, JiaRui Yang, JiLin Wang, Lulu Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉4-formyl dibenzo-18-crown-6 (FDB18C6) was synthesized through dibenzo-18-crown-6 (DB18C6), and it was added into polyvinyl alcohol (PVA) through acetal reaction to form a new type of membrane (F〈sub〉X%〈/sub〉-P). Then the F〈sub〉X%〈/sub〉-P membranes were immersed into the KOH solution to prepare F〈sub〉X%〈/sub〉-P-K membranes, which through the complexation of crown ion on K〈sup〉+〈/sup〉. The complex crown ether cation was successfully applied as anion conducting groups. The characterization and experimental results showed that F〈sub〉X%〈/sub〉-P-K membranes had already successfully synthesized, and possess better anionic conductivity and alkali resistance stability compared with other anion exchange membranes (AEMs). The water uptake and swelling ratio of F〈sub〉20%〈/sub〉-P-K membrane was reduced to 25.0% and 14.5%, separately, suppressed effectively the excessive swelling of PVA. And the dimensional stability of F〈sub〉20%〈/sub〉-P-K was 21.1%, which reflected excellent membrane stability. In addition, especially outstanding performance was the anionic conductivity of F〈sub〉X%〈/sub〉-P-K membranes increased from 7.63 mS·cm〈sup〉−1〈/sup〉 to 25.32 mS·cm〈sup〉−1〈/sup〉 at 70 °C, which confirmed excellent anionic conductive ability. After alkali treatment of preparing membranes, the conductivity degradation rate is less than 8.6% reflected superb alkali resistance. The aforementioned results defined that the F〈sub〉X%〈/sub〉-P-K membranes comply with the requirements in the anion exchange membrane fuel cell.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718314927-ga1.jpg" width="164" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 13 October 2018〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal〈/p〉 〈p〉Author(s): Francisco Nunes de Souza Neto, Renata Lang Sala, Renan Aparecido Fernandes, Tatielih Pardim Oliveira Xavier, Sandra Andrea Cruz, Caio Marcio Paranhos, Douglas Roberto Monteiro, Debora Barros Barbosa, Alberto Carlos Botazzo Delbem, Emerson Rodrigues de Camargo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Acrylic resin employed in dental materials can act as substrate for microorganisms’ adhesion and biofilm formation. To overcome this, silver nanoparticles (AgNPs) were combined with poly(methyl methacrylate) (PMMA) to reduce denture stomatitis caused by 〈em〉Candida glabrata〈/em〉. Although AgNPs antimicrobial activity is already known, the physicochemical properties of its nanocomposites, which dictate the performance of these commercial targets remain little explored. We evaluated the effect of different amount of AgNPs in PMMA obtained by the thermal polymerization. Among the mechanical tests employed, PMMA flexural strength decreased with higher AgNPs concentration. The microbiological adhesion test against 〈em〉Candida glabrata〈/em〉 revealed the nanocomposite with 0.05% of AgNPs has greater capacity to inhibit the biofilm formed on its surface. Although we observed distinct thermo-mechanical behavior in the presence of AgNPs, antimicrobial property was not linearly dependent of nanoparticles concentration and was influenced by nanoparticles dispersion and distribution in the polymer matrix.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305717322085-ga1.jpg" width="275" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Bufeng Zhang, Zhiyong Wei, Yabiao Zhao, Rui Che, Yanshai Wang, Xuefei Leng, Yang Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Biobased dihydroxy-terminated aliphatic copolyesters were synthesized from melt-polycondensation of 1,6-adipic acid with 1,6-hexanediol and 1,10-decanediol. The isodimorphic behavior of the copolyesters was explored to identify the pseudo-eutectic copolyester, which was selected as macro-initiator for ring opening polymerization of 〈span〉l〈/span〉-lactide to prepare poly(〈span〉l〈/span〉-lactide)-b-poly(hexamethylene-co-decamethylene adipate)-b-poly(〈span〉l〈/span〉-lactide) (PLLA-b-PHDA-b-PLLA) triblock copolymers varying PLLA block length. The blocky structure was confirmed by GPC and NMR, and the influence of PLLA block length on physical and mechanical properties was investigated. Impact testing showed that the impressive impact strength was achieved, that is, the values of PLLA10-PHDA-PLLA10 and PLLA20-PHDA-PLLA20 were largely enhanced to 357.2 J/m and 259.6 J/m, respectively, about 9–12 times greater than that of PLLA homopolymer (28.6 J/m). SEM micrographs of impact fractured surface showed that the triblock copolymers underwent a transition from brittle fracture of neat PLLA to ductile fracture, which is attributed to the introduction of flexible aliphatic polyester as middle soft building block of triblcok copolymers. This work demonstrated isodimorphic aliphatic copolyesters as midblock of PLLA-based triblock fully biobased biodegradable copolymers towards highly toughened PLLA material.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718320123-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: February 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 111〈/p〉 〈p〉Author(s): Bing Li, Zhongshun Yuan, John Schmidt, Chunbao (Charles) Xu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The submitted work presented new foaming formulations demonstrated for production of bio- phenol formaldehyde (BPF) resins and thermal insulation foams using raw kraft lignin (KL) as a green feedstock, reducing both petroleum-based phenol and formaldehyde by up to 50%. The obtained lignin-based BPF foams exhibited low apparent density (20–80 kg/m〈sup〉3〈/sup〉), strong compressive strength (up to 1.01 MPa), excellent thermal conductivity (0.03–0.048 W/m·K) and combustion properties (LOI: 32–33%), and satisfactory closed cell structure, all comparable to commercial phenol formaldehyde (PF) foams. These BPF foams, using KL, can act as flame retardant and insulation materials for construction or retrofitting of buildings, thereby future commercialization of these lignin-derived phenolic foams would lead to cleaner production of flame retardant and insulation materials using forestry and agricultural residues/waste.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718319098-ga1.jpg" width="265" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: March 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 112〈/p〉 〈p〉Author(s): Aiman A. Gulamhussein, Danyall Meah, Damian D. Soja, Stephen Fenner, Zakaria Saidani, Aneel Akram, Simran Lallie, Ashlyn Mathews, Culum Painter, Monique K. Liddar, Zain Mohammed, Lai Ki Chiu, Sabiha S. Sumar, Hannah Healy, Nabeel Hussain, Jaimin H. Patel, Stephen C.L. Hall, Timothy R. Dafforn, Alice J. Rothnie〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Amphipathic co-polymers such as styrene-maleic acid (SMA) have gained popularity over the last few years due to their ability and ease of use in solubilising and purifying membrane proteins in comparison to conventional methods of extraction such as detergents. SMA2000 is widely used for membrane protein studies and is considered as the optimal polymer for this technique. In this study a side-by-side comparison of SMA2000 with the polymer SZ30010 was carried out as both these polymers have similar styrene:maleic acid ratios and average molecular weights. Ability to solubilise, purify and stabilise membrane proteins was tested using three structurally different membrane proteins. Our results show that both polymers can be used to extract membrane proteins at a comparable efficiency to conventional detergent dodecylmaltoside (DDM). SZ30010 was found to give a similar protein yield and, SMALP disc size as SMA2000, and both polymers offered an increased purity and increased thermostability compared to DDM. Further investigation was conducted to investigate SMALP sensitivity to divalent cations. It was found that the sensitivity is polymer specific and not dependent on the protein encapsulated. Neither is it affected by the concentration of SMALPs. Larger divalent cations such as Co〈sup〉2+〈/sup〉 and Zn〈sup〉2+〈/sup〉 resulted in an increased sensitivity.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718311832-ga1.jpg" width="372" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 110〈/p〉 〈p〉Author(s): Xiang Li, Nóra Hegyesi, Yunchong Zhang, Zhiping Mao, Xueling Feng, Bijia Wang, Béla Pukánszky, Xiaofeng Sui〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work, the Pickering emulsion template method was used to introduce lignin nanoparticles into poly(lactic acid) (PLA) with improved dispersion. The effect of lignin as the stabilizer of Pickering emulsions was studied in this paper, including the thermal, rheological and mechanical properties of the blends. The PLA/lignin films had reduced light transmission in the UV light region, and Young’s modulus of PLA/lignin blends increased, while their tensile strength and elongation-at-break decreased as compared to neat PLA film. The introduction of lignin improved crystallinity of PLA from 7.5% to over 15%, and increased its decomposition temperature by about 10 °C. The lignin in the blends prepared using the Pickering emulsion template approach had much larger load bearing capacity than the dispersed lignin particles in the usual melt blended material. All the results indicated that the Pickering emulsion template method improves the dispersion of lignin (over 5.0 wt%) in PLA and improves UV protection, crystallinity, decomposition temperature and Young’s modulus of PLA.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305718320561-ga1.jpg" width="329" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 120〈/p〉 〈p〉Author(s): Jun Feng, Daiyong Ye〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In order to find an alternative method to effectively distribute ZnO, an inorganic photoinitiator, in the UV-cured films of waterborne polyurethane acrylates (WPUAs), toluene diisocyanate and hydroxyl acrylate were reacted onto the ZnO surface to prepare novel polymerizable ZnO photoinitiators, which were characterized by the Fourier transform infrared spectroscopy, X-ray diffraction analysis, particle size analysis, 〈em〉Zeta〈/em〉 potential analysis, energy dispersive spectroscopy, and thermogravimetric analysis etc. The thermogravimetric analysis data showed that the reacted content of hydroxyl acrylates on the ZnO surface was about 4.2%. Then, the polymerizable ZnO photoinitiators were added into UV-curable WPUAs to formulate UV-curable coatings. Effects of polymerizable ZnO contents and the types of hydroxyl acrylates on the properties of the UV-cured films were studied. Figures of scanning electron microscope showed that the modified ZnO was uniformly dispersed in UV-cured WPUAs films. The real-time UV-curing kinetics showed that the photopolymerization process of the UV-curable WPUAs was zero-order reaction. The UV-cured films’ properties proved the double bonds on ZnO could participate in the UV-curing reaction, which made better combination of ZnO as both inorganic photoinitiators and additives. Therefore, this investigation demonstrated a novel method for ZnO photoinitiators to have a good compatibility within organic coatings matrix.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719311097-ga1.jpg" width="287" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 120〈/p〉 〈p〉Author(s): Gina A. Guillory, Justin G. Kennemur〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The interplay between equilibrium ROMP thermodynamics and the regioregular insertion of allylic trialkylsiloxy-substituted cyclopentenes during propagation with Hoveyda-Grubbs 2nd generation catalyst at varying temperatures is investigated. In general, bulkier substituents reduce monomer conversion and increase regioregular insertion. However, polymerization entropy (Δ〈em〉S〈/em〉〈sub〉p〈/sub〉) also appears to play an important role on ROMP thermodynamics when compared to ring strain (Δ〈em〉H〈/em〉〈sub〉p〈/sub〉) which is typically the parameter of focus for the efficacy of low-strain monomer conversion. This analysis has allowed for the determination of a “Goldilocks” monomer (i.e. one that provides the best compromise of monomer conversion (56% conversion at −10 °C) and regioregularity (97% HT insertion) to be 3-(〈em〉tert〈/em〉-butyldimethylsiloxy)cyclopentene which has never before been explored or reported. Due to this study, this monomer has now been identified as the ideal choice for isotactic polypentenamer studies moving forward.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉 〈p〉A series of allylic trialkylsiloxy-substituted cyclopentene monomers are examined for their ROMP thermodynamic values and the amount of head-to-tail (HT) regioregular insertion they supply to their respective polymers. With the goal of finding the best of both worlds, a new monomer is found to polymerize with up to 56% conversion at −10 °C and an unprecedented level of HT insertion (97%). This discovery allows continuation of this monomer towards highly isotactic and regioregular polypentenamers.〈/p〉 〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719317082-ga1.jpg" width="233" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 120〈/p〉 〈p〉Author(s): Ondrej Sedlacek, Victor R. de la Rosa, Richard Hoogenboom〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Poly(2-oxazoline)s (in literature abbreviated as PAOx, POx, or POZ, herein referred to as PAOx) represent an emerging class of biocompatible polymers outperforming polyethylene glycol (PEG) in many aspects, including their high synthetic versatility and structural modularity. In this review, we provide a brief introduction to PAOx chemistry and biology to sketch their potential in biomaterials science. Further, we provide a detailed comprehensive overview of the literature on PAOx-protein conjugates with emphasis on their critical evaluation and comparison with analogous systems based on PEG. Based on this literature overview, PAOx seem to be an excellent alternative to PEG in the construction of therapeutic polymer-protein conjugates.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S001430571931571X-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 120〈/p〉 〈p〉Author(s): Izabela Zaborniak, Paweł Chmielarz, Krzysztof Matyjaszewski〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This article presents the state-of-the-art modification of wood and wood cell wall components 〈em〉via〈/em〉 atom transfer radical polymerization (ATRP). This paper primarily focuses on summarizing the ATRP techniques with an emphasis on methods carried out with diminished amounts of catalyst that were used to synthesize bioactive surfaces and functional biomaterials based on raw wood and wood cell walls components, such as a cellulose and lignin. The biocomposites have many potential applications, including stimuli-responsive drug delivery systems with controlled release, cationic gene carriers, adsorbents for removal of pollutants, membranes with protein binding capacities, antimicrobial and low-adherent surfaces, and fibers for the textile industry. Recent advances in preparation of biopolymers indicate that ATRP, in particular procedures with low catalyst concentration, have become excellent tools for the synthesis of advanced biomaterials with a wide range of industrial applications.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719312959-ga1.jpg" width="500" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 121〈/p〉 〈p〉Author(s): Akhtar Ali, Ikrima Khalid, Muhammad Usman Minhas, Kashif Barkat, Ikram Ullah Khan, Haroon Khalid Syed, Ayesha Umar〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Drug delivery systems based upon combination of natural and synthetic polymers are considered as stable formulations with promising release characteristics. In current research work, Chondroitin sulfate (Natural), Carbopol-934 (Synthetic) and 2-Acrylamido-2-methylpropane sulfonic based semi-interpenetrating hydrogels were synthesized through free radical polymerization technique using Ethylene Glycol Dimethylacrylate as a cross linker. Nine formulations with different concentrations of Chondroitin sulfate and Carbopol-934 were prepared. Structural and morphological characterization was accomplished by using SEM, FTIR, DSC, TGA and XRD. Chemical evaluation was carried out to explore pH independent swelling characteristics, porosity, drug entrapment efficiency, bioadhesive strength and 〈em〉in-vitro〈/em〉 drug release behavior. Results were then statistically analyzed and optimum formulation was selected by using numerical approach of 3〈sup〉2〈/sup〉 factorial design. Results confirmed the formation of stable and firm hydrogel formulation with pH independent and controlled release of Loxoprofen sodium. These hydrogel formulations can be used as suitable alternative to conventional drug delivery systems to achieve optimum therapeutic outcomes.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719314387-ga1.jpg" width="185" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 European Polymer Journal, Volume 121〈/p〉 〈p〉Author(s): Elisabeth Rossegger, Franz Pirolt, Stephanie Hoeppener, Ulrich S. Schubert, Otto Glatter, Frank Wiesbrock〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Considering the pseudo-livingness of the cationic ring-opening polymerization of various 2-oxazoline monomers, micelles formed by amphiphilic diblock copoly(2-oxazoline)s are potential candidates for drug delivery. Copoly(2-oxazoline)s of the composition poly(2-ethyl-2-oxazoline)〈sub〉100-n〈/sub〉-〈em〉block〈/em〉-poly(2-dec-9′-enyl-2-oxazoline)〈sub〉n〈/sub〉 (n = 5, 10, 15) were found to form micelles in aqueous solution. The hydrophobic cores of these non-spherical micelles could be crosslinked by the thiol-ene reaction with glycol dimercapto acetate, the ester bonds of which can be cleaved by esterases. While the hydrodynamic radii of the non-crosslinked micelles increased if the hydrophobic block of poly(2-dec-9′-enyl-2-oxazoline) grew larger, the opposite trend could be observed for the crosslinked micelles. In the course of an oil uptake study, the hydrodynamic radii of the crosslinked as well as non-crosslinked micelles increased. In oil-filled micelles of poly(2-ethyl-2-oxazoline)〈sub〉100-n〈/sub〉-〈em〉block〈/em〉-poly(2-dec-9′-enyl-2-oxazoline)〈sub〉n〈/sub〉 (n = 5, 10, 15), the hydrodynamic radii of the non-crosslinked micelles were significantly larger in comparison with the crosslinked ones in case of n = 5 and 10, while the hydrodynamic radii of non-crosslinked and crosslinked micelles were of the same range in case of n = 15. The changes of diameter in micelles with polar molecules such as Zidovudine covalently attached to the hydrophobic core support the proposed antagonism of the inclusion of non-polar/polar molecules into the micelles’ cores and the degree of crosslinking.〈/p〉〈/div〉 〈/div〉 〈div xml:lang="en"〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0014305719313266-ga1.jpg" width="216" alt="Graphical abstract for this article" title=""〉〈/figure〉〈/p〉〈/div〉 〈/div〉