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  • Chemistry  (10,474)
  • Inorganic Chemistry  (602)
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  • 1995-1999  (10,932)
  • 1950-1954
  • 1996  (10,932)
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  • 1995-1999  (10,932)
  • 1950-1954
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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Journal of science education and technology 5 (1996), S. 193-201 
    ISSN: 1573-1839
    Keywords: Chemistry ; chemistry education ; multiple intelligences ; imagery ; visual-spatial thinking
    Source: Springer Online Journal Archives 1860-2000
    Topics: Natural Sciences in General , Technology
    Notes: Abstract Chemistry has evolved from a science dominated by mathematics into a science highly dependent on spatial-visual intelligence. Yet the chemical content of introductory courses remains taught essentially the same as 40–50 years ago. Chemistry, today, is recognized by chemists as the molecular science. Yet, school chemistry is alienated from that perception. Thanks to the computer, young people are more comfortable with visual imaging than their instructors were at the same age. Thus the time is rife to reinvigorate chemistry education by means of the visual-spatial approach, an approach wholly in conformance with the way modern chemistry is thought about and practiced.
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  • 2
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 333-339 
    ISSN: 0887-624X
    Keywords: reactivity ratios ; microstructure ; 13C-NMR spectroscopy ; (vinyl acetate)/(glycidyl methacrylate) copolymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (Vinyl acetate)/(glycidyl methacrylate) (V/G) copolymers were prepared by free radical solution polymerization in benzene. Copolymer composition was determined by 1H-NMR spectroscopy. Comonomer reactivity ratios were calculated by Kelen-Tüdos (KT) and error-in-variables (EVM) methods. The values reactivity ratios calculated by these methods are rV = 0.03 ± 0.01; rG = 38.9 ± 6.20 (KT) and rV = 0.03 ± 0.002; rG = 39.5 ± 1.97 (EVM). The microstructure of V/G copolymers in terms of the distribution of V and G centered was obtained from 13C{1H}-NMR spectra using the carbonyl carbon resonance signals of V as well as G units. © 1996 John Wiley & Sons, Inc.
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  • 3
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 117-124 
    ISSN: 0887-624X
    Keywords: polyimide ; polyamide ; adamantane ; thermal properties ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1,3-Diaminoadamantane (I) was used as a monomer with various aromatic dicarboxylic acyl chlorides and dianhydrides to synthesize polyamides and polyimides, respectively. Polyamides having inherent viscosities of 0.10-0.27 dL/g were prepared by low-temperature solution polycondensation. The polyamides were soluble in a variety of solvents such as N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), pyridine, dioxane, and nitrobenzene. These polyamides had glass transition temperatures in the 179-187°C range and 5% weight loss temperatures occurred at up to 354°C. Polyimides based on diamine I and various aromatic dianhydrides were synthesized by the two-stage procedure that included ring-opening to form polyamic acids, followed by thermal conversion to polyimides. The polyamic acids had inherent viscosities of 0.14-0.38 dL/g. The glass transition temperature of these polyimides were in the 245-303°C range and showed almost no weight loss up to 350°C under air and nitrogen atmosphere. © 1996 John Wiley & Sons, Inc.
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  • 4
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 141-148 
    ISSN: 0887-624X
    Keywords: polyacrylic acid ; silicone rubber membrane ; plasma-induced graft polymerization ; homobifunctional membrane ; 1,1-diphenyl-2-picryhydrazyl ; surface modification ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polyacrylic acid (PAA) was grafted onto the surface of silicone rubber membrane (SR) by plasma-induced graft copolymerization (PIP). Ar-plasma was used to activate the surface of SR. Also, a determination was made of the influences of plasma treatment power, pressure, time, grafted copolymerization reaction time, and monomer concentration on polymerization yield. The surface properties of SR were measured by ATR-FTIR, ESCA, and SIMS. In those analyses, the elemental composition and different carbon bindings on the surface of SR were examined by ESCA with the amount of O1s/C1s being approximately 0.7 at 60 s by Ar-plasma treatment (60 W, 200 mtorr). The peroxide group introduced on SR was measured via 1,1-diphenyl-2-picryhydrazyl (DPPH). The optimum amount of peroxide groups was 6.85 × 10-8 mol/cm2 at 60 s of Ar-plasma treatment. The peroxide group (33D peak) was introduced onto the surface of SR by negative spectra of SIMS analysis after SR treatment by Ar-plasma. An increase was obtained in grafted polymerization yield with a region of 5 to 50% (v/v) of acrylic acid aqueous solution. Both sites of polyacrylic acid were detected after staining by toluidine blue O. That is, a homobifunctional membrane was developed via this surface modification method. © 1996 John Wiley & Sons, Inc.
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  • 5
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 261-270 
    ISSN: 0887-624X
    Keywords: chemically modified polymers ; addition reactions ; carboxybetaines ; reaction mechanisms and kinetics ; pyridines ; imidazoles ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A detailed study of the synthesis of betaine products that result from addition reactions of poly (4-vinylpyridine) and poly (N-vinylimidazole) as well as of their model compounds, with α,β-unsaturated monocarboxylic acids is presented. A reaction mechanism based on experimental observations and proved by kinetic analysis is proposed. It consists of two reactions: the addition, which involves two molecules of acid and leads to X+B--like structures, where the cation X+ results from the addition of the amino nitrogen to the double bond of acid and B- is the carboxyl anion, and an equilibrium reaction between X+B- and the betaine structure X±. The latter occurs only in protic solvents and is coupled with the addition reaction. The process was especially investigated in methanol, because this solvent allows determination of the kinetic parameters. Some values of the addition rate constants are given. The study is based on 1H-NMR measurements and observations. © 1996 John Wiley & Sons, Inc.
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  • 6
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 301-303 
    ISSN: 0887-624X
    Keywords: thermosensitive polymer ; water soluble polymer ; polymer modification reaction ; poly(vinylamine) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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  • 7
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 157-163 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: From data in the literature on relative rates of copolymerization it has been possible to evaluate two constants, Q and e, characteristic of an individual monomer, which appear to account satisfactorily for its behavior in copolymerization. The constant Q describes the “general monomer reactivity” and is apparently related to possibilities for stabilization in a radical adduct. The constant e takes account of polar factors influencing copolymerization.
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  • 8
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 357-365 
    ISSN: 0887-624X
    Keywords: processable polyimides ; poly(pyromellitimide)s ; rigid-rod polyimides ; polyimides ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: From imidazole-blocked 2,5-bis[(n-alkyloxy)methyl]-1,4-benzene diisocyanates and pyromellitic dianhydride a series of new rigid-rod polyimides (Cn-PY-PI; n = 4, 6, 8) having linear and flexible (alkyloxy)methyl ((SINGLE BOND)CH2OCnH2n + 1; n = 4, 6, 8) side chains were prepared and characterized and their properties were measured and discussed with regard to effects of side chains. Incorporation of the side chains onto the rigid main chain greatly enhanced the solubility and fusibility of the polymers, and melting point of C8-PY-PI was determined to be 277°C. The UV-VIS absorption behavior was independent of side-chain length. TGA thermograms revealed a two-step pyrolysis behavior, in which the side chains split off separately at lower temperatures. X-ray diffractograms showed that all the polyimides are crystalline at room temperature. Sharp reflections in small-angle region obviously indicated the presence of a layered crystal structure. © 1996 John Wiley & Sons, Inc.
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  • 9
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 481-492 
    ISSN: 0887-624X
    Keywords: poly(benzobisthiazoles) ; sulfonated poly(benzobisthiazoles) ; rigid rod polymers ; polyelectrolytes ; thermally stable polymers ; conducting polymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Aromatic polyelectrolytes based on sulfonated poly(benzobisthiazoles) (PBTs) have been synthesized by a polycondensation reaction of sulfo-containing aromatic dicarboxylic acids with 2,5-diamino-1,4-benzenedithiol dihydrochloride (DABDT) in freshly prepared polyphosphoric acid (PPA). Several sulfonated PBTs, poly[(benzo[1,2-d:4,5-d′]bisthiazole-2,6-diyl)-2-sulfo-1,4-phenylene] sodium salt (p-sulfo PBT), poly[(benzo[1,2-d:4,5-d′]bisthiazole-2,6-diyl)-5-sulfo-1,3-phenylene] sodium salt (m-sulfo PBT), their copolymers, and poly[(benzo[1,2-d:4,5-d′]bisthiazole-2,6-diyl)-4,6-disulfo-1,3-phenylene] potassium salt (m-disulfo PBT), have been targeted and the polymers obtained characterized by 13C-NMR, FT-IR, elemental analysis, thermal analysis, and solution viscosity measurements. Structural analyses confirm the structures of p-sulfo PBT and m-disulfo PBT, but suggest that the sulfonate is cleaved from the chain during synthesis of m-sulfo PBT. m-Disulfo PBT dissolves in water as well as strong acids, while p-sulfo PBT dissolves well in strong acids, certain solvent mixtures containing strong acids, and hot DMSO. TGA indicates that these sulfonated PBTs are thermally stable to over 500°C. Free-standing films of p-sulfo PBT, cast from dilute neutral DMSO solutions, are transparent, tough, and orange in color. Films cast from basic DMSO are also free standing, while being opaque and yellow-green. p-Sulfo PBT was incorporated as the dopant ion in polypyrrole, producing conductive films with conductivities as high as 3 S/cm and electrical anisotropies as high as 10. © 1996 John Wiley & Sons, Inc.
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  • 10
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 517-518 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 11
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 721-728 
    ISSN: 0887-624X
    Keywords: polyurethane ; metal ions ; synthesis ; coordination ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of polyurethane organometallic complexes based on novel diols, bis[N-[[2-hydroxyphenyl]methylene]hydroxylethyleneamino]-copper(II) (DBSICu), were synthesized successfully. The products are elastomeric glassy materials or powders. Similar to other polyurethane elastomers, these coordination block copolymers exhibit 2-phase microstructure and thermoplastic properties. It is interesting to note that some of these polyurethanes show a Schlieren pattern under the polarizing optical microscope. The liquid crystalline properties of DBSICu and the coordination polymers are studied in detail in this study. © 1996 John Wiley & Sons, Inc.
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  • 12
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 747-754 
    ISSN: 0887-624X
    Keywords: poly(amide-imide)s ; bis(trimellitimide)s ; 3,3-bis[4-(4-aminophenoxy)phenyl]-phthalimidine ; triphenyl phosphite John Wiley & Sons, Inc. ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of novel bis(phenoxy)phthalimidine-containing poly(amide-imide)s III were synthesized by the direct polycondensation of 3,3-bis[4-(4-aminophenoxy)phenyl]phthalimidine (BAPP) with various aromatic bis(trimellitimide)s in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide-imide)s III, having inherent viscosities up to 1.36 dL/g, were obtained in quantitative yields. All resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All the soluble poly(amide-imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 267-322°C and the 10% weight loss temperatures were above 490°C in nitrogen. Some properties of poly(amide-imide)s III were compared with those of the corresponding isomeric poly(amide-imide)s III′ prepared from 3,3-[4-(4-trimellitimidophenoxy)phenyl]-phthalimidine and various aromatic diamines. © 1996 John Wiley & Sons, Inc.
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  • 13
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 801-809 
    ISSN: 0887-624X
    Keywords: zwitterion ; hydroxide inner salt ; polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The zwitterion, 1-[4-[(4-hydroxy-1-naphthyl)thio]butyl]quinuclidinium hydroxide inner salt, was synthesized from tetrahydro-1-(4-hydroxy-1-naphthyl)thiophenium hydrochloride and quinuclidine and characterized by NMR and IR spectroscopy. Polymerization of the zwitterion was studied over the temperature range 175-225°C. The polymer was identified as poly(1,4-piperidinediylethyleneoxy-1,4-naphthylenethiotetramethylene) based on NMR and IR spectroscopy. The polymer was found to contain 3-butenylthio and 4-hydroxy-1-naphthyl end groups. Based on the signal area of the olefinic end group, the polymer M⊼n varied between 8500 and 13,000. The highest molecular weight was achieved at the lowest temperature, indicating that termination became more favored at higher temperature. A mechanism is proposed to describe the polymerization. © 1996 John Wiley & Sons, Inc.
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  • 14
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 833-838 
    ISSN: 0887-624X
    Keywords: allyl glycidyl ether ; acrylonitrile ; copolymerization ; gamma-rays ; reactivity ratios ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolymers of allyl glycidyl ether (AGE) with acrylonitrile (AN) have been prepared by bulk polymerization of their monomers with gamma rays. Copolymers thus obtained were characterized by Fourier transform infrared (FTIR), and ultraviolet (UV) spectroscopic techniques. The composition of the copolymers is determined indirectly by FTIR, UV, and directly by elemental analysis. The results obtained by different methods are compared. The reactivity ratios of monomer pairs (AGE + AN) which copolymerized heterogeneously were calculated by using different methods of determination. Among the three experimental methods used for the analysis of compositions and two theoretical methods of computations, the elemental analysis technique and the application of nonlinear least-squares method gave the most reliable reactivity ratios. These are found to be 1.86 and 0.21 for acrylonitrile and allyl glycidyl ether, respectively. © 1996 John Wiley & Sons, Inc.
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  • 15
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 869-884 
    ISSN: 0887-624X
    Keywords: hot-melt polycondensation ; siloxane-modified sulfone-containing epoxy resin ; PMPS ; PDMS ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Siloxane-modified sulfone-containing epoxy resins (ESBS) were prepared by polycondensation of PMPS and/or PDMS siloxane oligomers with EBS, the sulfone-containing epoxy resin. Structures were analyzed by IR, 1H-, and 13C-NMR. The siloxane content in the copolymers was determined by 1H-NMR with an integration technique. Epoxy equivalent weight (EEW) determination indicated that the oxirane ring of EBS was intact with this hot-melt procedure. The GPC measurement of these ESBS copolymers showed that molecular weight (MW) increased with increasing siloxane content in PMPS-modified copolymers. Evidence of siloxane incorporation in the copolymer was discussed. © 1996 John Wiley & Sons, Inc.
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  • 16
    ISSN: 0887-624X
    Keywords: chain transfer ; addition-fragmentation ; peroxysilane ; radical polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ethyl 2-[1-(trimethylsilylperoxy)ethyl]propenoate 1, ethyl 2-[1-(dimethylvinylsilylperoxy)-ethyl]propenoate 2, ethyl 2-[1-(1-(2-ethoxycarbonyl-1-methyl-2-propenylperoxysilyl)-1-methylethylperoxy)ethyl]propenoate 3, and 2-phenyl-2-trimethylsilylperoxypropane 4 were synthesized and added to the free radical polymerization of vinylic monomers. 1 and 2 were found to show no homopolymerizability but act as effective chain transfer reagents in radical polymerizations of methyl methacrylate (MMA), styrene (St), and n-butyl acrylate (BA). The estimated chain transfer constants (Ctr) are as follows: Ctr (1) = 0.15 for MMA, 0.90 for St, and 2.03 for BA at 60°C; Ctr (2) = 0.12 for MMA, 1.16 for St, and 1.9 for BA at 60°C. 1H-NMR spectra of poly(St) formed in the presence of 1 is consistent with the view that the polymers bear an oxirane at one terminal and an trimethylsilyloxy fragment at the other end. Moreover, peroxysilane 4 showed very low transfer properties by direct homolytic substitution (SH2). These findings indicate that the ethyl 2-[1-(substituted dimethylsilylperoxy)ethyl]-propenoates 1-3 undergo chain transfer reaction via a intramolecular homolytic substitution (SHi) following an addition process. Preparation of poly(styrene) up to high conversion in the presence of 3 yielded to the formation of the corresponding polymeric structures bearing hydrolysable C(SINGLE BOND)O(SINGLE BOND)Si(SINGLE BOND)O(SINGLE BOND)C bonds. © 1996 John Wiley & Sons, Inc.
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  • 17
    ISSN: 0887-624X
    Keywords: emulsion terpolymerization ; control of microstructure ; monomer addition profile ; chemical composition distribution ; gradient polmer elution chromatography ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An optimal addition profile for the preparation of a chemically homogeneous emulsion terpolymer of styrene, methyl methacrylate, and methyl acrylate was determined using a recently developed model for describing composition drift in emulsion co- and terpolymerizations. TRISEPS, described in Part I of this series. The model uses recently published simplified equations to describe monomer partitioning and the terminal model for describing terpolymer composition. The optimal addition rate profile was determined from the calculated optimal addition profile with a purely empirical and iterative method. With gradient polymer elution chromatography (GPEC®) the homogeneity and/or heterogeneity of the terpolymers prepared in the iterative series of experiments could be determined and compared to the heterogeneity of the corresponding batch terpolymer described in Part I. It was shown that a homogeneous terpolymer could be obtained indicating that the simplified equations for monomer partitioning and the terminal model for terpolymer composition describe the system adequately. It was also shown that GPEC® was useful in the determination of the optimal addition rate profile. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 985-990 
    ISSN: 0887-624X
    Keywords: monovinylacetylene ; poly(vinylacetylene) ; anionic polymerization ; titration ; tertiary butyllithium ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A polymer consisting of a saturated carbon backbone with pendent acetylenic groups was prepared from monovinylacetylene. A titration was performed between the monomer and tertiary butyllithium, its lithiating agent. The charge transfer complex formed between the solvent THF and the tertiary butyllithium was used as an indicator of the unreacted butyllithium. Hence, a stoichiometric quantity of tertiary butyllithium was added dropwise to a solution of monovinylacetylene in THF to form lithiovinylacetylene. The addition of a slight excess of butyllithium led to the polymerization of the lithiated monomer. The obtained polymer was reprotonated and characterized. This polymerization was evaluated as a possible route to synthesize poly(vinylacetylene) with processable molecular weights, for its application as a potential carbon fiber precursor. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 971-984 
    ISSN: 0887-624X
    Keywords: radiation ; polyisobutylene ; NMR ; GC/MS ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: GC, GC/MS, GPC, and Solution NMR spectra were used to study the γ radiolysis of polyisobutylene (PIB) in vacuum to different total doses (0-900 kGy) and at different temperatures (77-423 K). NMR spectra show a large number of new resonances with relatively narrow line widths, and a variety of NMR techniques have been employed to determine and quantify the structures associated with these new resonances. Chemical shift assignments were made by comparison with those for small molecule model compounds and predictions based upon calculations according to several different schemes. Chain-end structures have been proposed that account well for the majority of the new resonances, all being the result of an initial chain scission reaction initiated by the radiation. These assignments support some previous proposals for the mechanism of radiation degradation of polyisobutylene and exclude others. For example, NMR provides no evidence for the formation of ethyl chain ends and some of the main chain unsaturated structures previously proposed. NMR also indicate that at higher doses the chain end products formed during initial stages undergo secondary reactions. GC/MS data show the formation of oligomers during irradiation, which may be due to a backbitting mechanism. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1015-1024 
    ISSN: 0887-624X
    Keywords: ambifunctional monomers ; 1-propenyl ethers ; 1-butenyl ethers ; vinyl ethers ; cationic polymerization ; photopolymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of a novel series of ambifunctional monomers containing cationically polymerizable vinyl and 1-propenyl ether or 1-butenyl ether groups in the same molecule has been carried out. Studies of the onium salt-induced photopolymerizations of these monomers indicate that both functional groups are highly reactive and that they undergo extensive copolymerization. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1083-1085 
    ISSN: 0887-624X
    Keywords: poly(metyhylene sulfide) ; condensation polymerization ; catalysis ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The condensation polymerization of sodium sulfide with methylene chloride in various solvents was studied in order to assess the influence of polarity on the yield and composition of condensation products. The effect of addition of polyethylene glycol was also studied. It has been found that the overall yield of polythiomethylenes rises from 13.9% in methanol to 85.2% (methanol, PEG15000). The use of solvents of higher polarity promotes the linear oligomers, whereas in methanol the cyclic products predominate. In presence of PEG the this equilibrium is shifted towards tetrathiane. The observed phenomena are discussed in terms of solvents polarity and reaction media viscosity. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 909-910 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1183-1188 
    ISSN: 0887-624X
    Keywords: anionic polymerization ; polybutadiene ; triallylstannyllithium ; star polymer ; reversible chain transfer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The anionic polymerization of 1,3-butadiene using a novel metalloidal anion initiator, triallylstannyllithium (TALi)-allyllithium (ALi), was studied. The TALi-ALi initiated anionic polymerization of 1,3-butadiene gave the star polymer along with the linear polybutadiene (PBD). The star polymer consisted of three PBD branches and a central tin atom. What is striking is a fact that the number-average molecular weights (Mn) and molecular weight distribution of three PBD branches and linear PBD were almost identical. A reversible chain transfer polymerization mechanism, which includes the equilibrium between tri(macroallyl)-stannyllithium and macroallylic anion, is proposed. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1203-1208 
    ISSN: 0887-624X
    Keywords: plasma polymerization ; graft polymerization ; polyethylene ; poly(methylacrylate) ; membrane ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Using a plasma-induced graft polymerization technique, which is well known as a surface modification method, the grafted polymer was formed in pores of the porous material. This study examined the filling mechanism. Five thin porous films were sandwiched together, and employed as the substrate. The substrate was treated by plasma, and the change in surface tension and radical formation was measured for each sheet after the sheet was separated. The only surface on which surface-tension change was detected, was that of the sheet directly exposed to the plasma. Although plasma treatment made polymer radicals primarily on the outer surface of the sheet, the treatment also formed a few radicals inside the sheets. The radicals inside the sheets reacted with methylacrylate and grafted polymer formed in the pores. The location of grafted polymer depended on the balance between monomer diffusivity and reactivity. The grafting rate depended on which monomer solvent was used for the polymerization. Thus, the grafted membrane morphology could be controlled by varying the grating solvent composition. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1433-1441 
    ISSN: 0887-624X
    Keywords: aromatic polyamides ; ether-dicarboxylic acids ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 4,4′-(1,4-Phenylenedioxy)dibenzoic acid (3), 4,4′-(2,5-tolylenedioxy)dibenzoic acid (Me-3), and 4,4′-(2,5-biphenylenedioxy)dibenzoic acid (Ph-3) were prepared by the nucleophilic substitution reaction of p-fluorobenzonitrile with hydroquinone, methylhydroquinone, and phenylhydroquinone, respectively, followed by alkaline hydrolysis. Several aromatic polyamides having inherent viscosities of 0.66-1.34 dL/g were directly prepared by a Yamazaki phosphorylation polyamidation technique from dicarboxylic acids 3, Me-3, and Ph-3, respectively, with aromatic diamines using triphenyl phosphite and pyridine as condensing agents. The solubility of methyl- or phenyl-substituted polyamides was remarkably enhanced when compared to that of nonsubstituted analogues. Most of the substituted polyamides revealed an amorphous nature and were readily soluble in a variety of organic solvents including N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide, dimethyl sulfoxide, and m-cresol. Transparent, flexible, and tough films of these polymers could be cast from the DMAc or NMP solutions. These films had tensile strength of 60-100 MPa, elongation to break of 6-11%, and tensile modulus of 1.68-2.25 GPa. The glass transition temperatures (Tg) of most polyamides could be determined by differential scanning calorimetry (DSC) and were in the range of 200-232°C. Thermogravimetric analyses established that these polymers were fairly stable up to 450°C, and the 10% weight loss temperatures were recorded in the range of 458-535°C in nitrogen and 468-528°C in air atmosphere. In general, the phenyl-substituted polyamides exhibited relatively higher Tg, thermal stability, and solubility. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1475-1482 
    ISSN: 0887-624X
    Keywords: anion exchange membranes ; electrodialysis ; relative transport number between two anions ; effect of hydrophobicity on anion transport ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A membranous copolymer crosslinked with divinylbenzene reacted with N,N,N′,N′-tetra-methylethylenediamine, N,N,N′,N′-tetramethyl-1,3-propanediamine, and N,N,N′,N′-tetramethyl-1,6-hexanediamine to prepare highly crosslinked anion exchange membranes. More than 80% of both tertiary amino groups of the diamines reacted with chloromethyl groups of the membrane to form crosslinkage. After formation of the high crosslinkage of the membrane was confirmed with dialysis of a neutral molecule, electrochemical properties of the obtained membranes (mainly, relative transport number between two anions in electrodialysis) were evaluated: nitrate ions to chloride ions, sulfate ions to chloride ions, fluoride ions to chloride ions, and bromide ions to chloride ions. Though larger anions, in general, were difficult to permeate through the membranes due to high crosslinkage, the number of methylene groups of the diamines (which means the increase in hydrophobicity of anion exchange groups) also affected the relative transport number between two anions. The lower the hydration of anions, the higher the relative transport number of the anions through the membranes with the hydrophobic anion exchange groups. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1493-1500 
    ISSN: 0887-624X
    Keywords: 2,7-bis(4-maleimidophenoxy)naphthalene ; bismaleimide ; Michael addition ; naphthalene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Crosslinking of 2,7-bis(4-maleimidophenoxy)naphthalene (BMPN) and 4,4-bismaleimi-dophenylmethane (BMPM) was investigated in the presence of 4,4-diaminodiphenylmethane (DDM) at the 2/1 molar ratio of bismaleimide/DDM. Their curing behaviors were characterized by infrared spectroscopy and differential scanning calorimetry. The presence of a naphthalene group in the backbone of the bismaleimide increased the curing temperature and reduced the polymerization reactivity. The exotherm was shifted to a lower temperature as the amine addition lead to chain extension. Thermal behavior and properties of cured products were investigated by thermogravimetric analyses and dynamic mechanical analyses. Also, at this molar ratio, the properties of the BMPN/DDM showed better Tg, thermal decomposition temperature, and moisture resistance than the epoxy derived from 2,7-dihydroxynapthalene cured with DDM system (DGEDN/DDM). © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1517-1527 
    ISSN: 0887-624X
    Keywords: anionic polymerization ; styrenic monomers ; aggregate reactivity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The long-standing presumption that aggregated organolithium species are unreactive in hydrocarbons has been examined for styryllithium head-groups. A computer based curve-fitting evaluation of the equilibrium constants assumed to govern the perceived dimer: singlet equilibria for polystyryllithium in benzene, cyclohexane, and toluene was done. From the calculated concentrations of singlet head-groups and the experimental propagation rates, the rate constant (kp) values were obtained. Some values were approximately equal to or larger than those measured for the ion-pair in etherial solvents. These hydrocarbon solution values are improbably large, raising serious doubts about the validity of the mechanism upon which they are based. The data for the styrenic monomers in toluene also failed to lend support to that mechanism. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1581-1588 
    ISSN: 0887-624X
    Keywords: aromatic polyesters ; soluble aromatic polyesters ; alkoxy or phenyl substituted aromatic polyesters ; rigid polymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Rigid aromatic polyesters containing alkoxy or phenyl-substituted oligophenyls were prepared. Soluble polymers were obtained also in cases where phenyl-substituted quinquephenyl diols were combined with asymmetric phenyl-substituted terephthalic acid. The synthesized polyesters were characterized by viscosimetry, gel permeation chromatography, thermal analysis, and dynamic mechanical analysis. The temperature dependence of the intrinsic viscosity was sensitive to the type of side groups. Thermogravimetry has shown that polyesters with aromatic substituents were stable up to 380-400°C. The glass transition temperatures of the polyesters with aromatic side groups were in the 220-260°C range as determined by DSC. Polyesters with hexyloxy side chains show crystallinity. Dynamic mechanical analysis showed that in the cases where aromatic substituents were used to increase solubility, the obtained polymers have very useful mechanical properties at high temperatures. The polymer having the quinquephenyl unit in the main chain has an almost constant modulus up to 340°C. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1343-1346 
    ISSN: 0887-624X
    Keywords: citral ; reactivity ratios ; error-in-variables ; substituted styrenes ; methyl methacrylate ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1347-1351 
    ISSN: 0887-624X
    Keywords: biopolymer ; alkaline hydrolysis ; molecular weight control ; microorganism ; poly(γ-glutamic acid) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1483-1491 
    ISSN: 0887-624X
    Keywords: epoxidation ; epoxide ; functionalization ; partial hydrogenation ; styrene ; butadiene ; block copolymer ; SBS ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The preparation of partially saturated lightly functionalized styrene-butadiene block copolymers of polyA-block-polyB-block-polyA type (SBS) is described. The work involves epoxidizing partially hydrogenated SBS block copolymers using peracetic acid in a cyclohexane/water heterogeneous system. Five partially hydrogenated model polymers containing low levels of unsaturated aliphatic double bonds were used to study the epoxidation reaction and kinetics. The existence of the epoxide functional group on the product polymer was evidenced by IR and 1H-NMR spectra and the epoxide concentration was determined by direct titration. The partially hydrogenated SBS copolymers were more difficult to epoxidize than the unhydrogenated ones. The temperature dependence of the epoxidation rate was studied and the activation energy was determined as 8.8 kcal/mole of double bonds. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1407-1414 
    ISSN: 0887-624X
    Keywords: molecular orbital method ; MOPAC ; transition state ; addition polymerization ; ethylene ; methyl acrylate ; methyl methacrylate ; dimethyl itaconate ; N-methyl itaconimide ; differential photocalorimetry ; DPC ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Transition states (TSs) of radical addition homopolymerization reactions of methyl acrylate, methyl methacrylate, dimethyl itaconate, and N-methyl itaconimide were examined with two-unit radical models using MOPAC (PM3 UHF) semiempirical method. Calculated activation energies (Eas) show good correlations with experimental values. Calculated activation entropies (-ΔS
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1529-1541 
    ISSN: 0887-624X
    Keywords: living cationic polymerization ; methyl tri(ethylene glycol) vinyl ether ; isobutyl vinyl ether ; diblock copolymers ; water-soluble polymers ; amphiphiles ; micelles ; hydrodynamic size ; critical micelle concentration ; cloud point ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Water-soluble diblock copolymers of methyl tri(ethylene glycol) vinyl ether (hydrophilic block) and isobutyl vinyl ether (hydrophobic block) of different molecular weights and composition were synthesized by living cationic polymerization. The molecular weight and comonomer composition of these copolymers were determined by GPC and 1H NMR spectroscopy, respectively. Aqueous solutions of the copolymers were characterized in terms of their micellar behavior using dynamic light scattering, aqueous GPC, and dye solubilization. All the copolymers formed aggregates with the exception of a diblock copolymer with only two hydrophobic monomer units. The micellar hydrodynamic size scaled with the 0.61 power of the number of hydrophobic units, in good agreement with a theoretical exponent of 0.73. An increase in the length of the hydrophobic block at constant hydrophilic block length or an increase in the overall polymer size at constant block length ratio both resulted in lower critical micelle concentrations (cmcs). The cloud points of 1% w/w aqueous solutions of the polymers were determined by turbidimetry. An increase in the length of the hydrophobic block at constant hydrophilic block length caused a decrease in the cloud points of the copolymers. However, an increase in the overall polymer size at constant block length ratio led to an increase in the cloud point. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1421-1431 
    ISSN: 0887-624X
    Keywords: polyamides ; “five-ring” ; dicarboxylic acids ; fluoro-displacement ; triphenyl phosphite ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The five benzene rings-containing (hereafter referred to as “five-ring”) dicarboxylic acids α,α′-bis[4-(4-carboxyphenoxy)phenyl]-1,4-diisopropylbenzene (p-III) and α,α′-bis[4-(4-carboxyphenoxy)phenyl]-1,3-diisopropylbenzene (m-III) were prepared by the fluoro-displacement of α,α′-bis(4-hydroxyphenyl)-1,4-diisopropylbenzene and α,α′-bis(4-hydroxyphenyl)-1,3-diisopropylbenzene with p-fluorobenzonitrile, and subsequent alkaline hydrolysis of the intermediate dinitriles. A number of high-molecular-weight polyamides based on these two “five-ring” dicarboxylic acids (p-III and m-III) and various aromatic diamines were directly synthesized in N-methyl-2-pyrrolidone (NMP) containing lithium chloride (LiCl) or calcium chloride (CaCl2) using triphenyl phosphite and pyridine as condensing agents. These polyamides were obtained with inherent viscosities above 0.51 and up to 0.91 dL/g. The weight-average molecular weight were in the range of 51,000-211,000. Most of these polyamides were amorphous and readily soluble in polar solvents such as NMP, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO), and afforded tough, flexible, and transparent films by solution-casting. The films had tensile strength of 50-83 MPa, elongation to break of 4-8%, and tensile modulus of 1.3-2.0 GPa. Most polyamides showed distinct glass transitions on the differential scanning calorimetry (DSC) curves ranging from 147 to 177°C. In nitrogen or air, all the polymers showed no significant weight loss up to 490°C, as indicated by thermogravimetric analysis (TG). © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1511-1516 
    ISSN: 0887-624X
    Keywords: poly(ethylene terephthalate) ; surface treatment ; VUV photochemistry ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(ethylene terephthalate) was exposed to radiation from different kinds of low-pressure plasmas in an oxygen atmosphere. The lower wavelength limit of the spectrum investigated, λ = 112 nm, is the cut-off of magnesium fluoride used for separating the specimen chamber from the plasma light source. The total surface oxygen concentration, and the formation of hydroxyl, carbonyl, and carboxyl groups were evaluated from XPS measurements in combination with chemical derivatizations, and their dependences on the radiation spectrum and the oxygen pressure in the sample chamber have been investigated. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1543-1552 
    ISSN: 0887-624X
    Keywords: polyester ; polyolefin and blend ; macromonomer and epoxy ; epoxy ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Methods for preparing saturated polyolefin oligomers with Si(SINGLE BOND)H, epoxy groups, and with dihydroxy groups have been developed. Anionic polymerization of butadiene, then termination of the chains with chlorodimethylsilane leads to controlled molecular weight oligomers with silane functionality, and wherein the microstructure can be tailored. Hydrogenation of these materials proceeds smoothly using colloidal nickel catalysts to yield the corresponding saturated materials, which are stable to conditions used for melt polyesterifications. Hydrosilation of allyl glycidyl ether with the Si(SINGLE BOND)H end groups produces epoxy functional oligomers, and subsequent hydrolysis of the epoxy rings yields oligomers with a dihydroxy group at one end. Melt copolymerization of the olefin macromers with 1,4-butanediol and 1,4-dimethylcyclohexanedicarboxylate in the presence of titanium isopropoxide affords poly(ester-g-olefin) graft copolymers. These copolymers are under study as model interfacial agents for polyester/polyolefin blends and as suspension agents for polyester particles in nonpolar media. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1553-1560 
    ISSN: 0887-624X
    Keywords: conducting polymers ; poly(isothianaphthene) ; mechanism of formation ; phthalic anhydride ; phthalide ; phosphorus pentasulfide ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The results of some mechanistic studies on the formation of poly(isothianaphthene) from phthalic anhydride and phthalide by reaction with phosphorus pentasulfide (P4S10) are described. Based on the observed intermediates during the polymerization and their reactivity, it is proposed that both reactions occur by a sequence of substitution (thionation), isomerization, and polymerization reactions. P4S10 is the most efficient reagent for the conversion of phthalic anhydride and phthalide, and Lawesson's Reagent (a commonly used thionating reagent) gives less satisfactory results. It is suggested that P4S10 assists the rate-determining step. Oxygen-containing monomers do not polymerize in the absence of a thionating reagent under the conditions for the synthesis of PITN, thereby keeping the incorporation of oxygen into the polymeric backbone to a minimum. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1567-1572 
    ISSN: 0887-624X
    Keywords: pyrolysis ; polypyrrolone film ; electrical conductivity ; carbonization ; graphitization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effects of the pyrolytic temperature on the structure of the pyrolyzed polypyrrolone (PMDA-DAB) films were investigated. The structure of pyrolyzed PMDA-DAB film was characterized by elemental analysis, XPS spectra, x-ray diffraction, and SEM images. It suggests that the pyrolysis process of PMDA-DAB films consists of carbonization and graphitization processes, and the transitional temperature is at ca. 800°C. During carbonization process (Tp 〈 800°C), most oxygen is removed and the enhancement of conductivity with the pyrolytic temperature may be due to an extended conjugation of π-electron orbitals resulting in an increase of the number of charge carriers. During graphitization (Tp 〉 800°C), both oxygen and hydrogen are removed completely, and an increase in the mobility of charge carriers may increase conductivity with pyrolytic temperature. A graphite-like structure with heterocyclic rings containing nitrogen atoms is proposed for the PMDA-DAB film pyrolyzed at 1200°C. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1609-1611 
    ISSN: 0887-624X
    Keywords: copper(I) iodide ; p-xylylene dibromide ; potassium carbonate ; poly[(p-xylylene carbonate)-co-(p-xylylene oxide)] ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1589-1595 
    ISSN: 0887-624X
    Keywords: graft polymerization ; peroxide group ; carbon black ; polymeric peroxide ; radical trapping ; vinyl polymer ; dispersibility ; e-value ; surface modification ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The introduction of peroxide groups onto carbon black surface was achieved through the trapping of the peroxide radicals formed by the decomposition of polymeric peroxide, such as poly(tetraethylene glycol peroxyadipate) (ATPPO), and bis-peroxide, such as 1,1′-bis (t-butyldioxy)cyclohexane (Perhexa-C), by the surface: the amount of peroxide groups introduced onto carbon black surface by the treatment with ATPPO and Perhexa-C were determined to be 0.07 mmol/g and 0.12 mmol/g, respectively. The polymerization of vinyl monomers with positive e-value, such as methyl methacrylate and 2-hydroxyethy methacrylate, was successfully initiated by the peroxide groups introduced onto carbon black surface. During the polymerization, the corresponding polymers were effectively grafted onto the surface as a result of the propagation of polymer from the surface radicals formed by decomposition of the peroxide groups. The polymerization of vinyl monomers with negative e-value, such as styrene and vinyl acetate, however, was scarcely initiated by the peroxide groups on carbon black. This may be due to the fact that surface active radicals, which were formed by the hydrogen abstraction from carbon black by fragment radicals, inhibit the polymerization of vinyl monomers with negative e-value. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1613-1615 
    ISSN: 0887-624X
    Keywords: ethyl nitrate ; DMSO ; poly(vinyl ester) ; poly(vinyl acetal) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1617-1621 
    ISSN: 0887-624X
    Keywords: dipropargyl derivatives ; carbazole ; palladium-catalyzed polycondensation ; crosslinking ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1373-1383 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Many 2,6-disubstituted phenols are readily oxidized with oxygen, a tertiary amine and a copper (I) salt being used as catalyst. The products are diphenoquinones (I) or 1,4-polyphenylene ethers (II):The effect of variation of the substituents on the phenol and the infrared spectra of the polymers is discussed. Amine complexes of copper salts are the only effective catalysts found for the polymer-forming reaction. The effect on the catalyst of varying the copper salt and the ligand is discussed.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1651-1655 
    ISSN: 0887-624X
    Keywords: polybutenes ; ethene-propene copolymer ; amidoalkylation ; trifluoroacetic acid ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Amidoalkylations of polybutenes and of ethene-propene copolymer, catalyzed by trifluoroacetic acid, result in 5,6-dihydro-4H,1,3-oxazino-substituted polyalkenes with the 2-position of the oxazine ring unsubstituted or occupied by a vinyl or a phenyl group. The vinyl-substituted dihydrooxazino polymers thus obtained readily add butylamine to the vinyl fragment yielding alkylamino-substituted derivatives. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1819-1822 
    ISSN: 0887-624X
    Keywords: cyclic carbonate ; L-phenylalanine ; ο-hydroxy carboxylic acid ; polycondensation ; DCC ; DMAP ; poly(ester-urethane) ; 1-methyl-2-fluoropyridinium salt ; trypsin ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1823-1826 
    ISSN: 0887-624X
    Keywords: hybrid inorganic/organic IPN ; porous materials ; poly(styrene) ; silica gel nanotubes ; mesoporous hexagonal silica ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1713-1721 
    ISSN: 0887-624X
    Keywords: polyurethane anionomers ; ionic diols ; methylene spacers ; TGA ; DSC ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ionic diols with varying methylene spacers were prepared from maleic anhydride and linear diols. Reaction across the unsaturated site by aqueous sodium bisulphite was used to prepare the ionic diols. Chain extended polyurethane ionomers were prepared by the reaction of prepolymer based on different polyols and diisocyanates with the ionic diols. The polyurethane anionomers were characterized by FT-IR and FT-NMR spectroscopy. The differential scanning calorimetric results show that Tg of the anionomers shifted towards low values as the ionic content in the polyurethane increases and as the length of the ionic diol increases. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1733-1740 
    ISSN: 0887-624X
    Keywords: LC side-group block copolymer ; morphology ; phase separation ; LC behavior ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Liquid crystalline triblock copolymers with LC inner block and amorphous outer blocks have been synthesized by “living” anionic polymerization and investigated using DSC, TEM, and small-angle x-ray diffraction. All samples of poly[styrene-block-2-(3-cholesteryloxycarbonyloxy) ethyl methacrylate-block-styrene] (PS-b-PChEMA-b-PS) show liquid crystalline behavior and phase separation between the blocks. Compared to triblock copolymers with PS inner block (PChEMA-b-PS-b-PChEMA) and diblock copolymers (PS-b-PChEMA) the LC block copolymers with PS outer blocks have the same properties. The LC behavior and the morphology do not depend on the block arrangement; they are only influenced by the volume fractions of the blocks. Those samples in which the liquid crystalline subphase is not continuous (spheres) only a nematic phase was found, whereas in all samples with a continuous liquid crystalline subphase, the smectic A phase of the homopolymer was observed. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1753-1761 
    ISSN: 0887-624X
    Keywords: photopolymerization ; copolymers ; hydrogels ; biocompatible polymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The study of the homo- and copolymerization of furfuryl methacrylate (F) and vinylpyrrolidone (P) in bulk, initiated by the photoactivation of AIBN at low temperatures (0 and 40°C), is described. The kinetic diagrams for the homopolymerization of F and P were obtained following the evolution of the heat of reaction by DSC, and revealed the autoacceleration and the vitrification effects on the polymerization rate. The influence of oxygen in the photoinitiated polymerization was analyzed by determining the steady-state concentration of oxygen from the kinetic data obtained for polymerizations performed out in the presence and absence of oxygen. The results obtained indicate that P is more sensitive than F to the presence of oxygen in free radical polymerization. The photoinitiated copolymerization process is little affected by the concentration of monomers, giving similar Rp and θm values for both systems. However, at low polymerization temperature 0°C non-crosslinked copolymers are obtained, whereas at a temperature of 40°C, the copolymers prepared at conversion higher than 20 mol % become crosslinked as a result of the active participation of the furfuryl ring in the polymerization process at this temperature. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1783-1792 
    ISSN: 0887-624X
    Keywords: bis[4-(2-hydroxyethoxy)aryl] compound ; copolyester with naphthalene groups ; melt polycondensation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolyesters containing naphthalene structure were synthesized from bis(hydroxyethyl)naphthalate (BHEN) or bis(hydroxybutyl)naphthalate (BHBN) and various aralkyloxy diols. The starting bis[4-(2-hydroxyethoxy)aryl] compounds were derived from a nucleophilic substitution of various bisphenols with ethylene carbonate in the presence of KI. Copolyesters having intrinsic viscosities of 0.45-0.60 dL/g were obtained by the melt polycondensation in the presence of metallic catalysts. The effect of reaction temperature and time on the formation of copolyesters were investigated to obtain an optimum condition for copolyesters manufacturing. Most copolyesters have better solubilities than polyethylene naphthalate (PEN) or polybutylene naphthalate (PBN) in aprotic solvents, such as N-methyl-2-pyrrolidone or m-cresol. The thermal properties of the copolyesters were investigated by the differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Glass transition temperatures (Tg) of copolyesters result from BHEN were in the range of 90-141°C, and 10% weight loss in nitrogen were all above 460°C. Another series of copolyesters result from BHBN have Tg in the range of 75-135°C, and 10% weight loss in nitrogen of over 420°C. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1815-1818 
    ISSN: 0887-624X
    Keywords: 1,3-pentadiene ; cationic polymerization ; crosslinking ; chain transfer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1629-1629 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1827-1828 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1633-1634 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1635-1649 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: When, in a poly-α-olefin, the probability that a given placement be isotactic depends upon the tacticity of only a finite number of immediate predecessors, the resulting diastereosequence distribution obeys the theory of Markoff chains. When this is not the case, one says that the resulting diastereosequence distribution is non-Markoffian. A special case of a Markoffian distribution is given by a simple Markof chain in which the tacticity of a given placement is assumed to be affected by only the tacticity of the immediately preceding placement. Another special case is, of course, the Bernoulli trial distribution in which the probability that a given placement be isotactic is independent of the tacticity of all other placements. A high resolution NMR spectrum can sometimes yield a quantitative determination of the concentrations of isotactic and syndiotactic placements and the concentrations of the three types of possible adjacent pairs of such placements (i.e., isotactic, syndiotactic, and heterotactic pairs). When this is the case, the spectrum can be used to determine whether or not a given diastereosequence distribution is Bernoullian. However, because the longest diastereosequences whose concentration can be measured by NMR spectroscopy involve only two placements, an NMR spectrum cannot check whether a given non-Bernoullian distribution be simple Markoffian or Markoffian in general. In fact, non-Markoffian distributions are compatible with existing NMR spectra on polymers prepared by anionic polymerizations. In this paper we work within the framework of Kac's theory of stationary statistical processes and point out some general results which are valid for both Markoffian and non-Markoffian processes. The results are applied to NMR spectroscopy and it is pointed out which calculations used to check the self-consistency of NMR data and to obtain the mean length of closed diastereosequences are valid for both Markoffian and non-Markoffian distributions.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1873-1880 
    ISSN: 0887-624X
    Keywords: cation exchange membranes ; pre-irradiation grafting ; FEP ; styrene ; states of water ; Chemistry ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
    Notes: The structure and some physico-chemical properties of radiation grafted FEP-g-polystyrenesulfonic acid proton exchange membranes were studied as a function of the degree of grafting. The distribution of grafted polymer across the membrane thickness was obtained from microprobe measurements. It was found that for low levels of grafting (ca. 3%), polystyrene chains are located near the membrane surface only, and the interior of the membrane remains ungrafted. With the increasing degree of grafting, polystyrene chains were incorporated into the interior of the membrane as well. An almost homogeneous distribution of grafts in the membrane was obtained at a graft level of 〉 13%. The influence of the degree of grafting on membrane properties, such as ion exchange capacity, swelling, and specific resistivity was studied. Three different states of water, viz., freezing free, freezing bound, and nonfreezing water have been identified in noncrosslinked membranes. However, the nature and the amount of crosslinker had a profound influence on the states of water in a membrane. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1897-1905 
    ISSN: 0887-624X
    Keywords: poly(aryl ether ketone)s ; poly(aryl ether phthalazine)s ; fluorinated ; high Tg ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two series of novel amorphous poly(aryl ether phthalazine)s have been prepared via an intramolecular ring closure reaction of poly(aryl ether ketone)s (PAEKs) with hydrazine monohydrate. Fluorinated PAEKs, which display solubility in solvents incorporating a ketone functionality such as acetone or ethyl acetate, were converted to poly(aryl ether phthalazine)s to observe if these polymers would display similar solubility characteristics. The poly(aryl ether phthalazine)s have glass transition temperatures in the range of 278-320°C and show 5% weight loss points greater than 500°C in air and nitrogen atmospheres. The fluorinated poly(aryl ether phthalazine)s were not soluble in ketonic solvents. A series of poly(aryl ether phthalazine)s incorporating pendant 2-naphthalenyl moieties has been prepared in an attempt to produce amorphous, thermally stable polymers with high glass transition temperatures. The polymers have glass transition temperatures in the range of 287-334°C and show 5% weight loss points greater than 500°C in air and nitrogen atmospheres. Poly(aryl ether phthalazine)s undergo an exothermic reaction above the glass transition temperature. The major product of this reaction is a rearrangement of the phthalazine moieties to quiazoline moieties, however some crosslinking of the polymers occurs. Cured samples of the poly(aryl ether phthalazine)s show a small increase in the polymer Tg and are insoluble in all solvents tested. © 1996 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 34:1897-1905, 1996
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1923-1931 
    ISSN: 0887-624X
    Keywords: phthalazines ; quinazolines ; poly(aryl ether)s ; thermochemistry ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(aryl ether phthalazine)s were found to undergo an exothermic reaction at a temperature range of 360-440°C. We elucidated the origin of the exothermic reaction and the physiochemical phenomena associated with it, based on thermal analyses, model compound studies, and 13C solid-state NMR studies. At elevated temperatures, polymers containing a diphenylphthalazine moiety 4 underwent extensive thermal crosslinking reactions as a result of a nitrogen elimination reaction of the phthalazine moiety. However, polymers containing the tetraphenyl or hexaphenyl phthalazine moiety 5 and 6 were found to undergo principally a backbone rearrangement reaction, in which the phthalazine moiety rearranged to a quinazoline. Utilizing this efficient thermal rearrangement of polyphenylated phthalazines, we have prepared a novel activated difluoride, 2,4-bis(4-fluorophenyl)-,5,6,7,8-tetraphenylquinazoline 9d, which underwent high-temperature solution polycondensation with BPA to give the quinazoline containing poly(aryl ether) 14. Polymer 14 is amorphous, has a glass transition temperature of 264°C, and has high thermooxidative stability with 5% weight loss being recorded at 514°C in nitrogen. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1951-1957 
    ISSN: 0887-624X
    Keywords: p-vinylbenzyl glycidyl ether ; itaconic acid monomethyl ester ; radical polymerization ; polymer yield ; gel fraction ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymers containing both pendant carboxyl and epoxy groups were synthesized by the radical copolymerization of p-vinylbenzyl glycidyl ether (VBGE) and itaconic acid monomethyl ester (IAME). The copolymerization proceeded smoothly under various conditions, and polymer soluble in 1,4-dioxane with no gel fraction was obtained. However, the carboxyl-epoxy addition reaction between VBGE and IAME was observed, when DMSO or DMF were used as polymerization solvents. The IR and 1H-NMR spectrum of copolymers of VBGE and IAME showed the corresponding structure. The thermal crosslinking reaction of the resulting copolymers was examined under various conditions. Tetrabutylammonium bromide (TBAB) showed catalytic activity for the reaction. However, a 100% gel fraction of polymer was achieved after only 15 min without any catalyst, when the crosslinking reaction was performed at 150°C. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1993-2001 
    ISSN: 0887-624X
    Keywords: 2-vinyloxy ethyl phthalimide ; 1-(isobutoxy) ethyl acetate ; cationic polymerization ; Chemistry ; Polymer and Materials Science
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    Topics: Chemistry and Pharmacology
    Notes: 2-Vinyloxy ethyl phthalimide (ImVE) was polymerized using 1-(isobutoxy) ethyl acetate as the initiator in the presence of ethyl aluminum dichloride and either ethyl acetate or ethyl benzoate. The resulting polymers have a narrow molecular weight distribution, and their molecular weight can be controlled within a narrow range by varying the monomer and initiator concentrations. Diblock copolymers with n-butyl vinyl ether can also be formed. The behavior of the polymerization is consistent with a living cationic mechanism. A brief comparison of the title system with other initiating systems is also presented. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2387-2397 
    ISSN: 0887-624X
    Keywords: poly(vinyl chloride) ; nucleophilic substitution ; stereospecific mechanisms ; solvent influence ; microstructural sensitivity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The nucleophilic substitution in poly(vinyl chloride) (PVC) with sodium benzenethiolate has been studied in two kinds of solvent differing in the molecular structure in the vicinity of the carbonyl group. From the evolution of the content of isotactic (mm), heterotactic (mr), and syndiotactic (rr) triads; and of mmmm, mmmr and rmmr isotactic pentads, in the unmodified parts of the polymer, as followed by 13C-NMR, it is unambiguously inferred that any chlorine but the central one of either the isotactic triad at mmr tetrads or the heterotactic triad at rmrr pentads is unreactive. Only a small fraction of mmr tetrads reacts occasionally by the central chlorine of its mr triad instead of the mm. Of those structures, the mmr, especially when located at the end of long isotactic sequences, proves to be highly reactive compared to the rmrr structure. By comparing quantitatively the microstructural changes with degree of substitution and taking into account that the reaction is of SN2 type, the mechanisms of substitution through the three foregoing reactive chlorines have been stated. They are found to be independent of the type of solvent and to account for all the changes in triad and pentad content as experimentally found. Instead, the solvent dependence of the ratio between the mmr- and rmrr-based processes of substitution is such that the depletion of mmr compared to that of rmrr structure may be controlled. The conformational sensitivity of this behavior is discussed on the basis of side work in our laboratory. As a whole, the results of the present work provide some original concepts as to the role of the tacticity dependent microstructure and the related local conformations in the chemical reactions of PVC. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2421-2438 
    ISSN: 0887-624X
    Keywords: poly(ethersulfone) ; Udel® ; lithiation ; sulfination ; sulfonic acid ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new process has been developed for the sulfonation of arylene polymers which can be lithiated, like polysulfone Udel®. The sulfonation process consists of the following steps: (1) lithiation of the polymer at temperatures from -50 to -80°C under argon, (2) gassing of the lithiated polymer with SO2; (3) oxidation of the formed polymeric sulfinate with H2O2, NaOCl, or KMnO4; (4) ion-exchange of the lithium salt of the sulfonic acid in aqueous HCl. The advantages of the presented sulfonation procedure are: (1) in principle all polymers which can be lithiated can be subjected to this sulfonation process; (2) by this sulfonation procedure the sulfonic acid group is inserted into the more hydrolysis-stable part of the molecule; (3) this process is ecologically less harmful than many common sulfonation procedures. The sulfonated polymers were characterized by NMR, titration and elemental analysis, by IR spectroscopy, and by determination of ionic conductivity. Also the hydrolytic stability of the sulfonated ion-exchange polymers was investigated. Polymers with an ion-exchange capacity of 0.5 to 3.2 mequiv SO3H/g Polymer have been synthesized and characterized. The following results have been achieved: membranes made from the sulfonated polymers show good conductivity, good permselectivity (〉90%), and good hydrolytic stability in 1N HCl and water at temperatures up to 80°C. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2473-2479 
    ISSN: 0887-624X
    Keywords: pulsed-laser polymerization ; styrene ; propagation rate constant ; polymerization kinetics ; parameter estimation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: For a temperature range of -11.8-92.6°C, the propagation rate constant kp of styrene has been determined with the use of pulsed-laser polymerization (PLP). The temperature dependency of the obtained kp data was evaluated using the Arrhenius equation. The NLLS error-in-variables method (EVM) is recommended for this fit. The resulting activation energy is 32.6 kJ mol-1 and the pre-exponential factor is 107.66 dm3 mol-1 s-1. A joint confidence interval for these parameters is given. © 1996 John Wiley & Sons, Inc.
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    ISSN: 0887-624X
    Keywords: macromonomer ; poly(N-isopropylacrylamide) ; polystyrene microspheres ; thermosensitivity ; water dispersibility ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermosensitive microspheres with 0.4-1.2 μm diameter consisting of a polystyrene core and poly(N-isopropylacrylamide) (polyNIPAAm) branches on their surfaces were prepared by the free radical polymerization of a polyNIPAAm macromonomer and styrene in ethanol. Electron spectroscopy for chemical analysis (ESCA) of the microsphere surface suggested that polyNIPAAm chains were favorably located on the surface of the microspheres. The morphology of the microspheres was observed by transmission electron micrograph (TEM) and the particle size of was estimated by submicron particle analyzer. The molecular weight of the polyNIPAAm macromonomer, the ratio of the macromonomer and styrene, and the polymerization temperature affected the particle size. Thermosensitive properties of polyNIPAAm-coated polystyrene microspheres were evaluated by the turbidity of their dispersion solutions and the hydrodynamic size of the miocrospheres. The transmittance in dispersion solutions changed clearly, similar to oligoNIPAAm and polyNIPAAm macromonomers. In addition, the particle size of microspheres decreased with rising temperature. These results were explained by the thermosensitivity of polyNIPAAm branches on the microsphere surface. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2595-2602 
    ISSN: 0887-624X
    Keywords: poly(N,N-diethylacrylamide-co-glycol methacrylate) ; diethyldithiophosphate ; transesterification ; polymer synthesis ; gels ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ester exchange reaction of poly(N,N-diethylacrylamide-co-glycol methacrylate) with O,O-diethyldithiophosphate is shown to result in attachment of functional dithio phosphate group onto gels. The presence of N,N-diethylacrylamide moieties in the gels causes the gels to collapse when heated above the lower critical solution temperature, whereas ionization of the dithio groups at pH 〉 1.6 leads to drastic swelling. Selectivity of diethyldithio group toward metal ions enables gels to preferentially bind copper over zinc or calcium. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 33-44 
    ISSN: 0887-624X
    Keywords: main-chain liquid crystal polymers ; segmented liquid crystal polymers ; synthesis ; characterization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Linear segmented polyurethanes based on poly(butylene adipate)s (PBA) of different molecular weight (Mn 2000, 1000, and 600), 4,4′-diphenylmethane diisocyanate (MDI) and the mesogenic diol 4,4′-bis-(6-hydroxyhexoxy)biphenyl (BHHBP) as well as the unsegmented polyurethane consisting of MDI/BHHBP units have been synthesized and characterized by elemental analysis, 13C-NMR and SEC. The thermal behavior and the morphology were studied by DSC, polarizing microscopy, and DMA. The properties of the MDI-polyurethanes were discussed in relation to the BHHBP chain extended 2,4-TDI-polyurethanes and common 1,4-butanediol chain-extended MDI products. MDI polyurethanes based on PBA (Mn 2000) exhibit a glass transition temperature Tg of about -40°C independent of the hard segment content up to ∼50% hard segments. At higher hard segment contents increasing Tgs were observed. Polyurethanes, based on the shorter polyester soft segments PBA (Mn 1000 or 600), reveal an increase in the glass transition temperatures with growing hard segment content. The thermal transitions caused by melting of the MDI/BHHBP hard segment domains are found at 50 K higher temperatures in comparison with the analogous TDI products with mesogenic BHHBP/TDI hard segments. Shortening of the PBA chain length causes a shift of the thermal transitions to lower temperatures. Polarizing microscopy experiments indicate that liquid crystalline behavior is influenced by both the content of mesogenic hard segments and the chain length of the polyester. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 81-87 
    ISSN: 0887-624X
    Keywords: 2-methylene-1,3-dioxolanes, benzoyl peroxide reaction of ; 2-methylene-1,3-oxazolidines, benzoyl peroxide reaction of ; polyacetals ; charge-transfer polymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of 2-methylene-1,3-dioxolanes and 2-methylene-1,3-oxazolidines with benzoyl peroxide (acceptor radical) and with N-ethylmaleimide (acceptor) was investigated. It was shown that benzoyl peroxide adds to monomers 1a and 1b, giving the corresponding linear diester amides 1a and 1b respectively. The oxazolidine 1c adds benzoyl peroxide, without ring opening, by addition to the exomethylene group. Together with N-ethylmaleimide the oxazolidines 1a or 1b produce deep-colored charge transfer complexes, resulting in high molecular poly-N-ethylmaleimides probably via a radical mechanism. The 1,3-dioxolanes 2a and 2b were radically polymerized to produce polyacetals by vinyl polymerization. 2c was polymerized to produce randomly containing acetal units and ester units. The mechanism of polymerization of 2e is complex, affording polymers of nonuniform character. 2-Methylene-4-phenyl-1,3-dioxolane polymerization leads to polyester as the main structure, and to a lesser degree polyacetal structures. The chemical structures of the polymers were confirmed by NMR spectra and elemental analysis. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2679-2688 
    ISSN: 0887-624X
    Keywords: oxazolines ; copolymers ; poly(N-acylethylenimines) ; olefin ; allyl ; pendant ; DSC ; WAXD ; crystalline ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Decenyl (D) and heptyl (H) oxazolines were copolymerized in o-dichlorobenzene solvent using methyl 4-nitrobenzenesulfonate as an initiator. A series of decenyl/heptyl oxazolines random copolymers (or DH copolymers) with a total degree of polymerization of 100 and narrow molecular weight distribution were obtained. These copolymers are considered as the poly(N-acylethylenimine)s with allyl pendant groups randomly attached to the far end of their polymethylene, (SINGLE BOND)(CH2)7(SINGLE BOND), side chains. The polymers were characterized by NMR, FT-IR. Both DSC and x-ray diffractometer demonstrated that the polymers are highly crystalline. © 1996 John Wiley & Sons, Inc.
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    ISSN: 0887-624X
    Keywords: oxazolines ; poly(N-acylethylenimines) ; poly(N-aroylethylenimines) ; copolymers ; allyloxy ; methoxyphenyl ; carboxyl ; mercaptoacetic acid ; pendant ; DSC ; WAXD ; crystalline ; surface properties ; adhesion ; anticorrosion ; coatings ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 4-Methoxyphenyl oxazoline (MPO) was synthesized from 4-methoxybenzonitrile and ethanolamine by using cadmium acetate as a catalyst. 4-Allyloxy phenyl oxazoline (APO) was synthesized from 4-allyloxybenzonitrile, which was made from 4-cyanophenol. A series of random copolymers of APO and MPO over the whole composition range, with an approximate degree of polymerization of 100, were synthesized. They are named as PAM(m/n), where m and n are the total number of APO and MPO monomer units. All the polymers are crystalline and show birefringence. Their melting points decrease with the increase of mole fraction of MPO, from 240°C for PAM(100/0) to 199°C for PAM(20/80), and then increase to 226°C for PAM(0/100). We reacted mercaptoacetic acid with the PAM(m/n) copolymers to generate polar groups that could strongly bond with metal surfaces. They are named as PAM(m/n)-SCH2COOH, which correspond to their starting PAM(m/n) copolymers. They were characterized by NMR, DSC, hot stage melting, water contact angle, peel strength measurements, and some preliminary anticorrosion tests on cold-rolled steel, electrogalvanized steel, and Zi/Ni electroplated steel. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2857-2865 
    ISSN: 0887-624X
    Keywords: naphthalene ; poly(amide-ester) ; direct polycondensation ; thermal stability ; mesophase ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of novel, fully aromatic high-molecular-weight poly(amide-ester)s was prepared by the direct polycondensation from terephthalic acid (TPA) and 2,6-naphthalene dicarboxlic acid (NDC) with various aromatic diols and diamines in the presence of diphenyl chlorophosphate (DPCP), LiCl, and pyridine. The structures and thermal properties of these synthesized poly(amide-ester)s were examined by FTIR, wide-angle x-ray diffraction (WAXD), differential scanning calorimetry (DSC), thermal polarized optical microscope, thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA). The effects of the kinds of the aromatic diols and diamines (bisphenyl units, naphthalene, and (un)substituted phenylene structures) on the thermal properties of the synthesized poly(amide-ester)s were investigated in this study. Strong interchain interactions were induced by using a 50:50 molar ratio of the amide groups to the ester groups, and, thus, no LC properties but good thermal stabilities were found in all of the synthesized poly(amide-ester)s containing naphthalene, substituted hydroquinone, or bisphenol segments in this study. However, another series of poly(amide-ester)s with a molar ratio of diamine to diol of 20:80 exhibited excellent mesophase stabilities, with various molar ratio of terephthalic acid (TPA) to 2,6-naphthalene dicarboxlic acid (NDC). © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 227-235 
    ISSN: 0887-624X
    Keywords: radical polymerization ; degradative transfer ; diphenylpicrylhydrazine ; 1,3-diphenylpropene ; fluorene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Degradative transfer reactions for diphenylpicrylhydrazine (DPPH-H), 1,3-diphenylpropene (DPP), and fluorene (FLU) have been examined using styrene and methyl methacrylate as monomers. A new procedure has been followed, depending upon analyses of polymers for end groups derived from azobisisobutyronitrile used as initiator for the polymerizations. The method requires information or assumptions about the efficiency of re-initiation during transfer particularly for a monomer, such as methyl methacrylate, for which disproportionation is prominent in the termination process. For DPPH-H, the efficiency of re-initiation is zero; for DPP and FLU with styrene, the efficiencies are close to unity but they are smaller when methyl methacrylate is used. © 1996 John Wiley & Sons, Inc.
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  • 73
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 217-225 
    ISSN: 0887-624X
    Keywords: hybrid monomer ; hybrid oligomer ; photoinitiated cationic polymerization ; photoinitiated radical polymerization ; vinyl ether moiety ; acrylate moieties ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New hybrid vinyl monomers with both cationic- and radical-polymerizable vinyl groups were synthesized by the reaction of bis[1(chloromethyl)-2-(vinyloxy)ethyl]terephthalate (3) with unsaturated carboxylic acids using 1,8-diazabicyclo[5.4.0]-undecene-7 (DBU) as a base. The reaction of 3 with methacrylic acid 4a was carried out using DBU in DMSO at 70°C for 24 h to give an 86% yield of the hybrid vinyl monomer (5a). Polycondensation of 3 with unsaturated dicarboxylic acids was also performed using DBU to give hybrid vinyl oligomers with radical polymerizable C (DOUBLE BOND) C groups (VR) in the main chain and cationic polymerizable vinyl ether moieties (VC) on the side chain. The photopolymerization of these hybrid vinyl compounds proceeded smoothly in bulk using either a cationic photoinitiator such as a sulfonium salt or a radical photoinitiator such as acyl phosphine oxide under UV irradiation. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 271-276 
    ISSN: 0887-624X
    Keywords: radical polymerization ; styrene derivatives ; kojic acid ; functional polymers ; complexation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A styrene derivative (1) bearing kojic acid moieties was prepared by the base-catalyzed reaction of p-formylstyrene with kojic acid. Hydroxyl groups in 1 were subjected to acetylation. Although 1 did not undergo radical polymerization, the acetylated styrene derivative (2) showed good radical homo- and copolymerizability. For instance, a polymer having the number average molecular weight (Mn) of 60,000 was obtained in almost quantitative yield (97%) by the polymerization of 2 in chloroform (1.5 M) at 60°C for 36 h using α,α′-azobis(isobutyronitrile) (AIBN, 5 mol %) as an initiator. Under similar conditions, copolymers of 2 with styrene were also obtained in high yield. By partial deacetylation of the copolymer with a triethylamine catalyst, a copolymer containing α-hydroxyketone structures originated from kojic acid moieties was successfully regenerated. The deacetylated copolymer can be crosslinked by complexation with metal salts such as Al3+. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 305-307 
    ISSN: 0887-624X
    Keywords: polymeric metalloporphyrins ; oxidation catalysts ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 155-156 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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  • 77
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 3103-3120 
    ISSN: 0887-624X
    Keywords: ketene acetals ; cyclic ketene acetals ; cationic polymerization ; photopolymerization ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A study of the photoinduced cationic polymerization of a novel series of cyclic and acyclic ketene acetal monomers was carried out. It was observed that the cyclic monomers underwent facile cationic polymerization to give high molecular weight polymers while the acyclic ketene acetals did not. Thermally induced polymerization was also observed on standing catalyzed by glass surfaces. Photoinduced cationic polymerizations employing both diaryliodonium and triarylsulfonium salt photoinitiators were studied. It was observed that the position and type of substitutents in the cyclic ketene acetals was the major factor in determining the proportion of vinyl and ring-opening polymerizations that take place. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2879-2888 
    ISSN: 0887-624X
    Keywords: thermosetting cyanate networks ; foams ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A general means of generating nanofoams from thermosetting materials was investigated. Foams were prepared from a thermosetting monomer copolymerized with a thermally labile material, such that the thermally labile coblock is the dispersed phase. Upon thermal treatment, the thermally unstable block undergoes thermolysis, leaving pores where the size and shape are dictated by the initial morphology. For this investigation the thermosetting resin was prepared from a cyanate monomer (4,4′-(hexafluoroisopropylidene) diphenyl-cyanate), with either poly(propylene oxide) or a propylene oxide-urethane copolymer as the thermally labile block. The propylene oxide-based oligomers were molecularly miscible with the cyanate resin over the entire range of compositions, and molecular weights investigated, but developed a two-phase structure upon reaction to form the polycyanurate thermoset. The molecular weight and composition of propylene oxide chemically incorporated into the polycyanurate was varied along with the curing condition, solvents, and catalyst. Dynamic mechanical and small-angle x-ray scattering measurements demonstrated a two-phase morphology in the cured networks wherein the propylene oxide domains are dispersed in the polycyanurate matrix. Upon decomposition of the propylene oxide component, however, the foam was found to collapse. Samples with the larger void size retained, to a large extent, their void composition upon the thermolysis of the propylene oxide component. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2915-2924 
    ISSN: 0887-624X
    Keywords: proteinoid ; aggregation ; fluorescence ; micelles ; methylene blue ; drug delivery ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polypeptide-based acidic proteinoid containing L-glutamic acid and L-aspartic acid in excess and five other neutral and basic amino acids in minor proportions have been synthesized and found that it forms organized aggregates in an aqueous solution. The proteinoid aggregate has been characterized using 13C-NMR, IR, and fluorescence spectroscopic techniques. The c.m.c. of the proteinoid has been determined by conductometric and pH metric methods. The aggregation studies were carried out at different temperatures and varying ionic strengths of the medium. The phase transition of the proteinoid aggregate has been determined using the fluorescence absorbance method. The aggregation behavior is shown to be dependent on the pH of the solution. This was also supported by conductivity measurements. Using methylene blue as a model drug, the drug delivery property of the proteinoid micelles were studied in acidic (pH 4.5) and neutral (pH 7.4) mediums. Using biphasic model thermochemical parameters, ΔG, ΔH, ΔS, and ΔCp have been evaluated. © 1996 John Wiley & Sons, Inc.
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  • 80
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2981-2989 
    ISSN: 0887-624X
    Keywords: electrocopolymerization ; aniline ; thiophene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In this study homopolymer, copolymer, and composites of aniline and thiophene were synthesized in nitrogen atmosphere by using TEATFB (Tetraethyl ammonium tetrafluoroborate) and Lithium perchlorate as supporting electrolytes. In order to analyze their structure and characteristics, IR spectrums of the samples were taken and thermogravimetric analysis (TGA) was applied. Also, the samples were photographed under scanning electron microscope (SEM) for microstructure analysis and their electrochemical properties were observed and conductivities were obtained by four probe method. Homopolymerization and copolymerization reactions were carried out in two different solvents viz. acetonitrile and benzonitrile in order to see the solvent effect on polymerization. However, changing the solvent was found to have no significant effect on the resulting properties. It was concluded that changing the supporting electrolyte caused a structural difference in the resulting homopolymer. It also affects the properties considerably. During the bilayer preparation changing the coating turn led to variations in the properties of the samples. When polythiophene (PT) was coated with polyaniline (PA), the resulting system was a composite. However, in coating PA with PT the system was identified to be a copolymer. © 1996 John Wiley & Sons, Inc.
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  • 82
    ISSN: 0887-624X
    Keywords: optically active poly(γ-ketosulfide)s ; cinchona and ephedra alkaloids ; asymmetric polyaddition ; induced optical activity ; circular dichroism ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Optically active poly(γ-ketosulfide)s having the asymmetric centers disposed along the main chain have been prepared by step polyaddition of 1,3-dimercaptobenzene to 4,4-dimethyl-2,5-cyclohexadiene-1-one, or to trans, trans-2,5-heptadiene-3-one, in the presence of catalytic amounts of chiral amines. The extent of asymmetric induction on the resulting polymeric product is found to be higher when the alicyclic ketone reagent is employed and is enhanced by lowering the catalyst concentration. The comparison of stereochemical features and chiroptical properties of appropriate low molecular weight analogues with those of the polymeric derivatives indicates that a comparable asymmetric induction occurs in polymers and model compounds, and that the former systems do not display appreciable evidence of ordered secondary structures, in agreement with a low stereoregularity degree along the macromolecular backbone. © 1996 John Wiley & Sons, Inc.
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  • 83
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    Keywords: phenothiazine ; fluorescence ; charge transfer complex ; photoinitiation ; C60 ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Four acrylic monomers bearing phenothiazine moieties, i.e., N-acrylyl-phenothiazine (APT), N-acrylyl-2-chlorophenothiazine (ACPT), N-acrylyl-2-acetylphenothiazine (AAPT), and 10-acrylyl-1-azaphenothiazine (AAzPT) were synthesized by dehydrohalogenation of the corresponding N-(β-chloropropionyl)-substituted phenothiazine derivatives with 1,8-diazabicyclo[5.4.0]undec-5-ene (DBU). These monomers could easily be polymerized by initiation with AIBN. The emission fluorescence spectra of the monomers and their polymers were recorded, which showed that the polymers displayed much stronger fluorescence than their corresponding monomers at the same chromophore concentrations. This phenomenon, as termed as “structural self-quenching effect,” was commonly observed for acrylic monomers bearing chromophore moieties and ascribed to the coexistence of the electron-donating chromophore and the electron-accepting double bond in the same molecule. Because of the formation of exciplex, the monomer APT, as well as ACPT, AAPT, AAzPT, and their polymers, could initiate the photopolymerization of AN. The charge transfer phenomenon between P(APT), P(ACPT), and C60 was also explored. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 2825-2825 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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  • 85
    ISSN: 0887-624X
    Keywords: hybrid fluorinated silicones ; silicon atom ; fluorinated chain ; hybrid homopolymers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of fluorinated hybrid silicones prepared in three steps from H2C—CH - C6F12—CH—CH2(I) and H2C—CHCH2 - C6F12 - CH2CH—CH2(II) is presented. First, both hydrosilylations of chlorodimethylsilane with these nonconjugated dienes were carried out in the presence of the Speier's catalyst leading to the expected bis-chlorosilane in excellent yield from (II) but giving a rearranged by-product from (I). However, a similar reaction from (I) initiated by a peroxide produced the expected bis-chlorosilane selectively. Second, these chlorosilanes were quantitatively hydrolyzed into the corresponding α,ω-bis silanols, whatever the spacer between the fluorinated group and the silicon atom. Finally, the polycondensations of these bis silanols were performed in the presence of an amine/acid adduct catalyst. Interestingly, the dihydroxysilane produced from (I) reacts much quicker than the other one. Moreover, thermal properties (Tg, Tdec) were investigated and compared to those of commercially available fluorosilicones or mentioned in the literature and show improvement of the behavior of these fluorosilicones at low and high temperatures. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 3263-3275 
    ISSN: 0887-624X
    Keywords: end group chemistry ; chemical modification ; fluoropolyether ; oligomer ; allyl ; epoxide ; polyol ; tetraol ; oxidation ; etherification ; NMR ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Different synthetic methods for the preparation of polyfunctional fluorinated oligomers were explored and the results compared. Fluoropolyether macromonomers bearing epoxy, allyl, and polyhydroxy end groups were synthesized and spectroscopically characterized. For obtaining a polyol (namely tetraol) functionality, a highly selective route was the reaction of the fluoropolyether macrodiol ZDOL with allylic halides and subsequent oxidation reaction at the C=C double bond by means of peroxyacids. This approach made it possible to obtain a segmented structure RH-RF-RH in which the molecular body RF consisted of a perfluoropolyether block endcapped by two hydrogenated segments RH, where RH = - CH2OCH2CH(OH)CH2OH. Unlike other more conventional syntheses, which always produce byproducts and higher molecular weight species such as RH-(RF-RH)n-RF-RH or RH-RF-(RH)n-, the described method offers high yields and selectivity. The fluoropolyether polyfunctional derivatives offer the possibility to prepare a variety of highly crosslinked fluorinated materials and, owing to their well defined regularly segmented structures, they also constitute interesting models for the understanding of basic structure-property relations of fluoro-oligomers and their copolymers. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 3071-3076 
    ISSN: 0887-624X
    Keywords: template polymerization ; poly(N-acyliminoethylene) ; molecular recognition ; hydrogen-bonding complex ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetic study of the photochemical polymerization of methacrylic acid (MAA) in aqueous dilute solution in the presence of poly(N-acetyliminoethylene) (PNAI) oligomers evidenced template features. The process proceeded in two stages, depending on [PNAI]/[MAA]0 ratio and polymerization duration, two different complexes being formed, both by a “zip” chain-growth mechanism. Computing and transmission electron microscopy data revealed that this aspect is due to the replacing of the initial PNAI template by the newly formed poly(methacrylic acid) daughter polymer, as a result of the structural peculiarities of the latter as a component of the primary complex. Its specific mode of packing in a complex aggregate was considered to be the main reason for the reported behavior. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 3061-3069 
    ISSN: 0887-624X
    Keywords: aggregation ; emulusion polymerization ; flocculation ; latex ; particles ; polymer ; size distribution ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The basic features of a three-step experimental process to produce supermicron polymer particles are described. First, a submicron emulsifier-free latex is prepared by a well-known technique. Second, the latex is aggregated by destabilizing with cetyl pyridinium chloride under constant stirring conditions, to yield roughly spherical clusters of 6-12 μ diameter. Third, the aggregates are stabilized with poly(vinyl alcohol) and internally coalesced by heating at or above the glass transition temperature. The final product particles have relatively smooth surfaces. Results are qualitatively interpreted in terms of a dynamic equilibrium where the aggregate size is determined by a balance between attractive interparticle potentials and stirring shear forces. Bimodal aggregate size distributions suggest the aggregate break-up mechanism may involve the erosion of individual latex particles and small fragments from the surface of aggregates. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 3255-3261 
    ISSN: 0887-624X
    Keywords: metathesis ; CVD ; polyacene-based structure ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2,4-Hexadiyn-1,6-diol (HDO) was polymerized on glass and silicon plates by chemical vapor deposition without transition metal catalysis to form homogeneous thin films. Structural properties of the films were investigated by FT-IR, UV-visible, Raman, x-ray diffraction, and XPS spectroscopic analyses. The structure of CVD-polymerized HDO (CVD-PHDO) films was different from that of metathesis polymerized HDO (metathesis-PHDO), showing a polyacene-based structure but no polyene structure with acetylenic side groups. © 1996 John Wiley & Sons, Inc.
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  • 90
    ISSN: 0887-624X
    Keywords: butyl acrylate ; methyl methacrylate ; vinyl acetate ; Bayesian design of experiments ; terpolymerization kinetics ; emulsion polymerization ; pilot plant experiments ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A systematic study of the terpolymerization of butyl acrylate/methyl methacrylate/vinyl acetate (BA/MMA/VAc) is being conducted. In this stage of the study, emulsion terpolymerizations were performed in a 5 L stainless steel pilot plant reactor. The experimental trials were of the two-level factorial type and were designed optimally using a Bayesian method. The design procedure allowed us to improve our knowledge about the process using our prior knowledge and our subjective judgement. The polymers produced were characterized for conversion, composition, molecular weight, and particle size. The Bayesian design of experiments is shown to have several advantages over conventional factorial designs. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 849-862 
    ISSN: 0887-624X
    Keywords: vinyl acetate ; emulsion polymerization of ; poly(vinyl alcohol) emulsifier ; poly(vinyl alcohol) ; grafting onto ; acetonitrile/water extraction ; water-soluble PVA ; water-insoluble PVA ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: During the emulsion polymerization of vinyl acetate (VAc) using poly(vinyl alcohol) (PVA) as stabilizer and potassium persulfate as initiator, the VAc reacts with PVA forming PVA-graft-PVAc. When the grafted polymer reaches a critical size it becomes water-insoluble and precipitates from the aqueous phase contributing to the formation of polymer particles. Since particle formation and therefore the properties of the final latex will depend on the degree of grafting, it is important to quantify and to characterize the grafted PVA. In this work, the quantitative separation and characterization of the grafted water-insoluble PVA was carried out by a two-step selective solubilization of the PVAc latex, first with acetonitrile to separate PVAc homopolymer, followed by water to separate the water-soluble PVA from the remaining acetonitrile-insoluble material. After the separation, the water-soluble and water-insoluble PVA were characterized by Fourier Transform Infrared (FTIR) spectroscopy and 1H and 13C nuclear magnetic resonance (NMR) analyses, from which the details of the PVA-graft-PVAc structure were obtained. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 705-705 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: No abstract.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 925-934 
    ISSN: 0887-624X
    Keywords: PVA ; crosslinking ; diisocyanates ; modification ; dianhydrides ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of acid chlorides with poly(vinyl alcohol) (PVA) leads to vinyl alcohol-vinyl ester copolymers. The esterification by Schotten-Baumann enables degrees of modification to be reached which depend on the chemical structure of the pendant unit introduced. High degrees of modification were obtained in the reaction with water-stable acid chlorides such as benzoyl or cinnamoyl chloride. The copolymers obtained were characterized by spectroscopic techniques, elemental analysis, thermal methods, and viscosity determinations. Since in all cases they were only partially modified, the remaining hydroxyl groups were reacted with difunctional hardeners, Epiclon B-4400, hexamethylene diisocyanate, and tolylene 2,4-diisocyanate, to obtain tridimensional networks. Vinyl alcohol-vinyl benzoate copolymers with different degrees of modification were crosslinked to study how the percentage of remaining hydroxylic groups affects the crosslinking process. The exotherm maximum of the curing process was lower when diisocyanates were used as hardeners and the degree of crosslinking was higher when hexamethylene diisocyanate was used according to the observed increase in Tg values. Whereas the TGA curves of linear polymers only showed one degradation, in crosslinked polymers two degradation steps were detected, suggesting several degradation mechanisms. © 1996 John Wiley & Sons, Inc.
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    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 963-969 
    ISSN: 0887-624X
    Keywords: substituted quinone methide ; polymerizability ; conjugative monomer ; electron-accepting monomer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 7,7-Bis(methoxycarbonyl)-, 7,7-bis(ethoxycarbonyl)-, and 7,7-bis(isopropoxycarbonyl)-1,4-benzoquinone methides (4a, 4b, and 4c) were successfully prepared as pure, isolable yellow-orange needles. The values of the first reduction potential for 4a, 4b, and 4c were measured in dichloromethane containing tetrabutylammonium perchlorate by cyclic voltammetry to be -0.54, -0.55, and -0.55 V, respectively, indicating that the alkyl groups do not significantly affect their electron-accepting properties. An anionic initiator butyllithium induced the homopolymerizations of 4a-c at 0°C, but a cationic initiator boron trifluoride etherate did not of 4a-c at 0°C. Compounds 4a and 4b homopolymerized with a radical initiator 2,2′-azobis(isobutyronitrile) (AIBN), but 4c did not, probably due to a larger steric hindrance effect of the isopropyl group compared with methyl and ethyl groups. Homopolymerizable compound 4a copolymerized with styrene in benzene in the presence of AIBN in a random fashion to give the monomer reactivity ratios r1 (4a) = 2.40 ± 0.40 and r2 (styrene) = 0.01 ± 0.02 at 60°C and the Q and e values of 4a were 21.2 and +1.13, respectively, indicating that 4a is a highly conjugative and electron-accepting monomer, while the nonhomopolymerizable compound 4c copolymerized with styrene in a perfectly alternating fashion in benzene in the presence of AIBN at 60°C. No copolymerizations of 4a or 4c with 7,7,8,8-tetracyanoquinodimethane took place in dichloromethane in the presence of AIBN at 60°C. © 1996 John Wiley & Sons, Inc.
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  • 95
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 997-1001 
    ISSN: 0887-624X
    Keywords: π-conjugated polymer ; n-type polymer ; reduction potential ; electron affinity ; linear relationship ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The ease of reduction of π-conjugated poly(p-phenylene)-, poly(naphthalene-2,6-diyl)-, and poly(naphthalene-1,4-diyl)-type polymers is determined by the electron accepting properties of the recurring aromatic units. Linear relationships hold between reduction potentials (Ered) of the π-conjugated poly(arylene)s and electron affinities (EA) of the recurring arylene units: Ered = ρEA + a. A ρ value of 0.85 ± 0.02 is found for the three types of polymers investigated. © 1996 John Wiley & Sons, Inc.
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  • 96
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1039-1047 
    ISSN: 0887-624X
    Keywords: PAmXD,6 ; Brabender plastograph ; hydrolysis ; condensation ; equilibrium constant ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: PAmXD,6 [poly(m-xylylene adipamide)] was processed using a Brabender plastograph at 30 rpm and at 265 ± 5°C. The evolution of the Mn versus mixing time determined from solution viscosity and chain end concentrations measurements shows that PAmXD,6 undergoes hydrolysis or condensation reactions depending on its initial molecular mass. Lower masses undergo condensation while higher masses undergo hydrolysis. The determination of water concentration in the melt during mixing time confirmed that this behavior is related to an equilibrium constant which was estimated at 500 ± 100. For a mixing period shorter than 20 min, a good correspondence was observed between Mn values determined either by chain end concentrations or by solution viscosity. However, for a mixing period longer than 20 min, discrepancy between Mn values using both methods witnesses the probable appearance of oxidative degradation of PAmXD,6. Mechanisms adapted from the established oxidation reactions of PA6 and PA6,6 are proposed to justify the PAmXD,6 behavior. Those reactions could explain the slight yellowing of PAmXD,6 during its processing. It was also shown that the PAmXD,6 Brabender plastograph mixing torque (30 rpm, 265 ± 5°C) is linearly related to Mn in a log/log diagram. © 1996 John Wiley & Sons, Inc.
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  • 97
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1049-1058 
    ISSN: 0887-624X
    Keywords: interpenetrating polymer networks (IPNs) ; differential scanning calorimetry (DSC) ; scanning electron microscopy (SEM) ; nonlinear optical (NLO) properties ; second harmonic generation (SHG) ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We report the synthesis and characterization of interpenetrating polymer networks (IPNs) exhibiting nonlinear optical (NLO) properties. The network consists of aliphatic polycarbonate urethane (PCU) and poly(methyl methacrylate-co-N,N-disubstituted urea), with a nonlinear optical (NLO) chromophore incorporated into N,N-disubstituted urea. The full IPNs have only one Tg, as determined by differential scanning calorimetry (DSC), together with scanning electron microscopy (SEM) observations, suggest a single phase morphology. The thin films of IPNs are transparent and the unpoled samples produced second harmonic generation (SHG) signals at room temperature. This result indicates that the NLO chromophore is oriented noncentrosymmetrically during the IPN formation process and is tightly held between the permanent entanglements of the two component networks of the IPN. © 1996 John Wiley & Sons, Inc.
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  • 98
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1095-1104 
    ISSN: 0887-624X
    Keywords: waterborne polyurethanes ; ionomers ; PCL ; PTAd ; PMVL ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Anionomer-type waterborne polyurethanes (PUs) were obtained from poly(β-methyl-δ-valerolactone) glycol (PMVL) and isophorone diisocyanate, following a prepolymer mixing process. The soft-hard segment phase separation in response to the variations of composition and structure of PU has been studied from the dynamic mechanical measurements of the emulsion cast films. The structural variation included ionic and hard segment content, molecular weight of NCO-terminated prepolymer, and type and length of the soft segment. It was found that phase separation is more sensitive to the soft segment length, rather than the soft segment content. With only phase separation, the rubbery modulus was significant even with lower hard segment content. Phase separation was much more pronounced with PU from poly(tetramethylene adipate) glycol, rather than from PMVL and poly(caprolactone) © 1996 John Wiley & Sons, Inc.
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  • 99
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    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 1105-1112 
    ISSN: 0887-624X
    Keywords: aromatic polyesters ; 1-phenyl-2,6-naphthalenedicarboxylic acid ; liquid crystallinity ; glass transition temperature ; melting temperature ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A series of new wholly aromatic polyesters was synthesized by melt polycondensation of 1-phenyl-2,6-naphthalenedicarboxylic acid (PNDA) and diacetates of various aromatic diols. The aromatic diols studied are hydroquinone (HQ), methylhydroquinone (MHQ), phenylhydroquinone (PHQ), (α-phenylisopropyl)hydroquinone (PIHQ), 2,6-naphthalenediol (2,6-ND), 1,4-naphthalenediol (1,4-ND), and 4,4′-biphenol (BP). These polyesters were characterized for their crystallinity, glass transition temperature (Tg), melting temperature (Tm), liquid crystallinity, and thermal stability. In general, crystallinity of the polyesters are very low and the Tg values of the polyesters range from 150 to 172°C depending on the structure of aromatic diols. All of the polymers formed nematic phases above their Tm or Tg. The polyesters derived from PHQ and PIHQ are soluble in chlorinated hydrocarbon solvents. The initial decomposition temperatures of the polyesters are above 400°C under N2 atmosphere. © 1996 John Wiley & Sons, Inc.
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  • 100
    ISSN: 0887-624X
    Keywords: bis(p-vinylphenyl) ether ; step-polymerization ; polymer structure ; mechanism ; kinetics ; molecular weight distribution ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A peculiar step-growth (cationic) polymerization of bis(p-vinylphenyl) ether (BVPE) in nonpolar or slightly polar aromatic solvents in the temperature range from 70 to 150°C in the presence of 2.5-5.0 mmol/L of p-toluenesulfonic acid has been studied. Optimum polymerization conditions were found. New linear unsaturated polymers of BVPE with terminal vinyl groups and weight-average molecular weight from 1500 to 10,000 were obtained. The structure and the formation mechanism of these oligomers and polymers were established, and the accompanying side reactions were considered. The rate constants were measured for eight temperatures, and the activation energy was found to be -42 kJ/mol. The optimum polymerization temperature was about 80°C. © 1996 John Wiley & Sons, Inc.
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