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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 37 (1974), S. 149-160 
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Pfropfung von Methylmethacrylatzweigen auf Cellulose durch Übertragungsreaktion wurde unter dem Einfluß von AIBN untersucht. Die Pfropfausbeute hängt von der Reaktionszeit, Temperatur, Monomerkonzentration, Initiatorkonzentration, vom Reaktionsmedium und von der Art des Substrats ab.
    Notes: Grafting of methyl methacrylate on cellulosic materials by chain transfer under the catalytic influence of azobisisobutyronitrile (AIBN) was extensively studied. The graft yield is influenced by reaction time, temperature, monomer and initiator concentration, reaction medium and nature of the substrate. In general, the grafting reaction shows an induction period after which the polymerisation proceeds rapidly. The graft yield increases and the induction period decreases by rising the reaction temperature from 50 to 70°C. This is also the case when the monomer concentration was increased from 2 to 6%. Increasing the AIBN concentration up to 0.01 M causes a significant enhancement in grafting while further increase brings about a marked fall in the graft yield. Among the reaction media studied, a water/solvent mixture containing 25% of either methanol, ethanol, propanol, butanol or acetone seems to constitute a reaction medium where the monomer and initiator are completely miscible and the swelling of cellulose by water is not hindered by the presence of these solvents. Increasing the solvent ratio in the water/solvent mixture causes a considerable decrease in the graft yield. The polymer content of the cellulosic materials, i. e. the graft yield, follows the order: partially carboxymethylated cotton 〉 cotton treated with 12N sodium hydroxide 〉 cyanoethylated cotton 〉 cotton treated with 0.5 N sodium hydroxide 〉 purified cotton. In addition, proof of grafting was provided by the fractional precipitation method.
    Additional Material: 6 Ill.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 101 (1981), S. 1-9 
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Mit Beize vorbehandeltes Baumwollgarn wurde locker mercerisiert, und locker mercerisiertes, nachverstrecktes Garn wurde in der Mercerisierungslösung auf 90, 94, 96, 100 und 103% der ursprünglichen Länge verstreckt. Die sechs so erhaltenen Substrate wurden zusammen mit der gebeizten Baumwolle mit Methylmethacrylat bzw. Acrylnitril unter Verwendung von Cer-Ammoniumnitrat als Initiator gepfropft. Pfropfgrad und Pfropfgeschwindigkeit waren bei der locker mercerisierten Baumwolle bedeutend höher als mit der gebeizten Baumwolle, unabhängig vom verwendeten Monomeren.Dasselbe gilt, jedoch in geringerem Maß, für vorbehandelte mercerisierte und auf 90% der Originallänge wiederverstreckte Baumwolle. Anders verhielt sich locker mercerisierte Baumwolle, die auf 94 und 103% wiederverstreckt war; diese Substrate zeigten einen niedrigeren Pfropfgrad und niedrigere Pfropfgeschwindigkeit als vorbehandelte Baumwolle. Außerdem erniedrigt sich die Pfropfausbeute und Pfropfgeschwindigkeit mit zunehmender Verstreckung. Ein ähnlicher Trend wurde beobachtet, wenn alle genannten Substrate mit Cerionen oxidiert wurden. Es wird angenommen, daß hier Unterschiede in der Mikrostruktur von gebeizter Baumwolle, locker mercerisierter Baumwolle und locker mercerisierter nachverstreckter Baumwolle verantwortlich sind.
    Notes: Scoured ply cotton yarn was slack mercerized and slack mercerized followed by restretching the yarn in the mercerizing solution to 90, 94, 96, 100, and 103% of the original length. The six substrates so obtained together with scoured cotton were grafted independently with methyl methacrylate and acrylonitrile using ceric ammonium nitrate as initiator. The extent and rate of grafting found with slack mercerized cotton were significantly higher than those of scoured cotton irrespective of monomer used.The same holds, but lo lesser degree, good for slack mercerized cotton followed by restretching to 90% of original length. Different situation was encountered with slack mercerized cotton followed by restretching to 94 and 103%; these substrates showed lower extent and rate of grafting than scoured cotton. Moreover, the extent and rate of grafting decreased by increasing the magnitude of stretching. Similar trend was observed when all the said substrates were subjected to oxidation with ceric ions. It is believed that there must be differences in microstructural features between scoured cotton, slack mercerized cotton and slack mercerized-restretched cottons that account for this.
    Additional Material: 4 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 213 (1993), S. 43-54 
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Pfropfcopolymerisation von Acrylamid (Aam) auf Maisstärke wurde mit Kaliumpersulfat als Initiator bei unterschiedlichen Reaktionsbedingungen, wie Initiatorbzw. Monomerkonzentration, Reaktionszeit und -temperatur sowie dem Feststoffgehalt untersucht. Basierent auf den erhaltenen Ergebnissen wurden die geeignetsten Bedingungen ausgewählt und den Pfropfpolymerisationen von anderen Monomeren auf Maisstärke zugrundegelegt. Von den eingesetzten Monomeren zeigte Acrylamid die größte Pfropffähigkeit, Acrylsäure die geringste; Acrylnitril und Methacrylsäure lagen dazwischen. Die Wasserlöslichkeit sowohl von stickstoffhaltigen als auch von Carboxygruppen enthaltenden Copolymeren steigt zunächst mit steigendem Momomergehalt an und sinkt ab einem bestimmten Wert wieder.
    Notes: Graft polymerization of acrylamide (Aam) onto maize starch using potassium persulfate as initiator was investigated under different conditions including concentration of initiator and monomer, polymerization time and temperature and liquor ratio. Based on the results obtained, appropriate conditions for grafting acrylamide onto starch were established. These conditions were also used for grafting other monomers onto maize starch. Results obtained indicate that acrylamide acquires the highest graft ability while acrylic acid acquires the least, while acrylonitrile and methacrylic acid in between. The water solubility of both nitrogen- and carboxy-containing copolymers increases by increasing the monomer content up to a certain value, then it decreases.
    Additional Material: 6 Tab.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 96 (1981), S. 59-68 
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Es wurde die durch 5wertiges Vanadium induzierte Pfropfcopolymerisation von Methylmethacrylat auf Nylon 6 untersucht. Die Pfropfausbeute sowie der Gesamtumsatz wurden in Abhängigkeit von der Vanadiumkonzentration, des Lösungsmittelgemisches sowie der Reaktionstemperatur bestimmt.
    Notes: Pentavalent vanadium ion (Vv)-induced graft polymerization of methyl methacrylate onto nylon 6 was investigated under a variety of conditions. Increasing the Vv-concentration up to 2 mmol/l was accompanied by an enhancement in grafting; the latter was not affected by further increase in Vv-concentration. Unlike grafting, the homopolymer and total conversion tended to increase by increasing Vv concentration. The graft yield enhanced significantly when the MMA-concentration was increased up to 3% further increase in MMA-concentration had no effect on grafting. Raising the polymerization temperature from 50° up to 70°C caused a significant increase in the rates of grafting, homopolymerization and total conversion. Using a solvent-water mixture as medium for polymerization affected considerably the magnitude of grafting. While using methyl alcohol, ethyl alcohol and acetone at any ratio in the solvent-water mixture resulted in decreased grafting, using an isopropyl alcohol-water mixture up to a ratio of 25 : 75 gave rise to increased grafting.
    Additional Material: 5 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 103 (1982), S. 143-152 
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Polymerisation von Allylmethacrylat und Nylon 6 und Dibenzoylperoxid als Initiator wurde unter verschiedenen Bedingungen durchgeführt. Die Ausbeute hängt von der Allylmethacrylat- und Dibenzoylperoxidkonzentration, der Polymerisationszeit, der Temperatur, sowie von der Zugabe von Metallsalzen oder organischen Lösungsmitteln ab. Die Ausbeute steigt mit zunehmender Initiatorkonzentration bis zu 0,5 mmol/l, sinkt dann aber bei weiterer Peroxidzugabe; sie nimmt zu mit steigender Allylmethacrylatkonzentration, untersucht von 80 bis 300 mmol/l. 85°C ist die optimale Polymerisationstemperatur, darunter und darüber wird eine geringere Ausbeute erhalten. Der Effekt der Polymerisationszeit ist mit der Polymerisationstemperatur verknüpft, es gibt keine Induktionszeit bei 95°C, dagegen 15 bzw. 30 Minuten bei 85 bzw. 75°C. Ein Zusatz von Cu+ + -Ionen zum Polymerisationsansatz verbessert die Ausbeute. Ähnlich ist es mit Fe+++ - und Li+ -Ionen. Ein Gemisch aus Wasser und einem organischen Lösungsmittel als Medium für die Polymerisation war vorteilhaft zur Erhöhung der Ausbeute, vorausgesetzt, daß das organische Lösungsmittel 1% bei Ethanol und Isopropanol und 4% bei Methanol nicht überstieg.
    Notes: Polymerization of allyl methacrylate with nylon 6 using benzoyl peroxide as initiator was carried out under different conditions. The polymer add-on was dependent upon allyl methacrylate and benzoyl peroxide concentrations, polymerization time and temperature as well as addition of metallic salts or organic solvents. The polymer add-on increased by increasing benzoyl peroxide concentration up to 0.5 mmol/l then decreased by further increase in peroxide concentration, whereas it increased as the allyl methacrylate concentration increased from 80 - 300 mmol/l. A polymerization temperature of 85°C constituted the optimal temperature, below or above this temperature resulted in lower polymer add-on. The effect of polymerization time was related to the polymerization temperature, no induction period occured at 95°C in contrast to 15 and 30 minutes at 85°C and 75°C, respectively. The incorporation of Cu+ +ions in the polymerization system improved the magnitude of polymer add-on. A similar situation was encountered with Fe+ + + and Li+ ions. Using a water/organic solvent mixture as a polymerization medium was advantageous in enhancing polymer add-on provided that the organic solvent did not exceed 1% in case of ethanol and isopropanol and 4% in case of methanol.
    Additional Material: 5 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 3137-3143 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ce(IV)-induced polymerization of allyl methacrylate (AMA) with cotton cellulose was investigated under a variety of conditions. Polymer add-on was directly related to AMA concentration. The same holds good for Ce(IV) ion concentration up to a certain concentration (30 mmol/L), after which it decreases. Polymer add-on was higher at 60 than at 50 and 70°C. A methanol/water mixture (20/80) offers the best medium for polymerization. Addition of nitric acid (up to 400 mol equivalent/L) or perchloric acid (up to 800 mol equivalent/L) to the polymerization system caused significant enhancement in polymer add-on. The reverse was the case with sulphuric acid irrespective of the concentration used. A comparison between polymer add-on values based on increase in weight and those based on estimated allyl double bonds indicated that the latter undergo partial homopolymerization.
    Additional Material: 5 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Acta Polymerica 33 (1982), S. 538-541 
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Cellulose sowie mit Methacrylsäure unterschiedlich gepfropfte Cellulose wurden mit Kaliumpersulfat bei verschiedenen Temperaturen und pH-Werten oxidiert. Die Oxidationsreaktion wurde hinsichtlich des Sauerstoffverbrauchs, des Masseverlustes, der Kupferzahl und des Carboxylgehaltes untersucht.
    Notes: Cellulose and cellulose grafted with methacrylic acid to different graft yields were oxidized with potassium persulphate at different temperatures and pH. The oxidation reaction was studied with respect to oxygen consumption, mass loss, copper number and carboxyl content of the samples.
    Additional Material: 8 Ill.
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  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 17 (1973), S. 2547-2556 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The ability of potassium permanganate in the presence of different acids to induce grafting of methyl methacrylate and acrylonitrile onto sodium hydroxide-treated cotton, partially carboxymethylated cotton, partially cyanoethylated cotton, and partially acetylated cotton was investigated. The copolymerization reaction was carried out under a variety of conditions. The graft yields are greatly enhanced by increasing concentration of monomer, reaction time, and temperature. The opposite holds true for initiator at higher concentrations. The effectiveness of the acids was: nitric acid 〉 sulfuric acid 〉 perchloric acid 〉 hydrochloric acid. The change in the physical and/or chemical structure of cellulose by its modification via etherification reaction or esterification reaction had a significant effect on the susceptibility of cellulose toward grafting. While partial carboxymethylation or partial cyanoethylation of cellulose prior to grafting increased the graft yield, partial acetylation caused a decrease.
    Additional Material: 7 Ill.
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  • 9
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Poly(glycidyl methacrylate) -starch graft copolymer was prepared using hydrogen peroxide/ferrous sulphate/thiourea dioxide redox system as initiator. The copolymer was treated with orthophosphoric acid (H3PO4) under a variety of conditions to discover appropriate conditions for synthesizing the copolymer that can serve as cation exchanger. Results obtained indicated that the cation-exchange capacity is enhanced by: (a) increasing the H3PO4/epoxy molar ratio up to 4; (b) using material-to-liquor ratio 1 : 2; (c) increasing duration (15-300 min) and temperature (60-90°C); (d) increasing the amount of epoxy groups of the copolymer; and (e) increasing the percent neutralization of H3PO4 up to 33.3%. Based upon the results obtained with these parameters, it was postulated that three reactions are involved during treatment of the copolymer with H3PO4. These reactions are phosphorylation, crosslinking, and hydrolysis. Conditions were established under which the phosphorylation reaction occurs exclusively. Studied also were the ion-exchange properties of the phosphorylated copolymer, namely, pKa values, capacity for heavy metal ions removal, moisture content, durability, swellability, and solubility.
    Additional Material: 4 Ill.
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  • 10
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 21 (1977), S. 1965-1970 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Grafting of nylon 66 with methyl methacrylate (MMA) under the initiating influence of dimethylaniline (DMA)-benzyl chloride (BC)-acetic acid (AC) mixture was studied to discover optimal conditions for grafting. Results of this investigation showed that a mixture of water/ethanol at a ratio of 90:10 constitutes the most favorable medium for the grafting reaction. Optimal grafting occurred when a concentration of 0.16 mole/l. DMA plus 0.17 mole/l. BC plus 0.2 mole/l. AC was used. Using lower or higher concentrations of this initiator led to lower grafting. On the other hand, increasing MMA concentration brings about a significant increase in the graft yield. The same holds true for reaction time and temperature, though an induction period was observed at a lower temperature (65°C) and when lower monomer concentration (2%) was used.
    Additional Material: 4 Ill.
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