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  • 1
    Electronic Resource
    Electronic Resource
    Studies on New Polyesters. Transition Temperatures of Poly[p-benzoyl(1,1-dimethyl-2-ethyl)oxy] (1980)
    s.l. : American Chemical Society
    Macromolecules 13 (1980), S. 1582-1587 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma60078a042
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    Paper (German National Licenses)
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  • 2
    Electronic Resource
    Electronic Resource
    Kinetics and mechanism of the formation of glycol esters: Benzoic acid-ethylene glycol system (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 3217-3239 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Esterification-hydrolysis and condensation-glycolysis are the principal equilibria entailed in a system comprised of benzoic acid, ethanediol, ethanediol monobenzoate, ethanediol dibenzoate, and water. These equilibria are characterized by three interrelated equilibrium constants that pertain to the hydrolysis of both ethanediol monobenzoate and ethanediol dibenzoate and to the condensation of ethanediol monobenzoate. The rate constants related to these reactions and to the corresponding reverse reactions were all found to be functions of the concentration of carboxy groups. Antimony triacetate, a well-known transesterification catalyst, catalyzed the condensation reaction strongly but did not affect the esterification reaction. Based on a mechanism that entailed the considered three principal equilibrium reactions, a set of both the kinetic and thermodynamic parameters was obtained by a nonlinear regression procedure. With these parameters the nonlinear rate equations were integrated numerically, using the fourth-order Runge-Kutta method. Excellent agreement between the values thus calculated and the experimental data were obtained in all cases except when considerable concentrations of both benzoic acid and ethanediol dibenzoate were present in the system. It has been concluded that in these instances the formation of the dibenzoate is paralleled by a pyrolysis reaction that is strongly catalyzed by carboxy groups.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.170171013
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Terephthalic acid esterification kinetics: 2-(2-methoxyethoxy)ethyl terephthalates (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 3241-3254 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The process of esterification of terephthalic acid is characterized by a mechanism that involves three equilibrium reactions. Two are esterification-hydrolysis equilibria entailing the reactions of the two terephthalic acid carboxyl groups with alcoholic hydroxyl groups, whereas the third one is a transesterification-acidolysis equilibrium that is concerned with the reaction between two terminal terephthalic acid moieties. The products of these three interrelated equilibria are terephthalic acid, its monoester and diester, the particular alcohol, and water. The alcohol used in the present study was 2-(2-methoxyethoxy)ethanol. Equilibrium constants and rate constants were developed from experimental data obtained at 230°C. The esterification-hydrolysis reactions were found to be catalyzed by carboxyl groups, and the rate of transesterification was found to be a function of the terephthalic acid concentration. With the constants developed, the system of nonlinear differential equations, as derived from the mechanism postulated, was integrated numerically using the Runge-Kutta method. Good agreement between calculated and experimental values was observed.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.170171014
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  • 4
    Electronic Resource
    Electronic Resource
    Synthesis of poly(ester carbonate) copolymers (1980)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 18 (1980), S. 75-90 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of poly(ester carbonate) copolymers based on bisphenol A, terephthalic acid, and phosgene is reviewed, and a new synthetic route is described leading to polymers which are different from those obtained by methods described in the literature. The most important features of the new method are quantitative incorporation of the dicarboxylic acid into the polymer and absence of undersirable side reactions. Synthesis of the random copolymer in which the dicarboxylic acid and carbonic acid groups are present in about equal molar amounts is discussed. Solution properties, effects of M̄n and copolymer composition on Tg, sequence length distribution, the effect of ester interchange reactions on molecular weight distribution, and effects of monofunctional chain termination on molecular weight of the final product are also discussed.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1980.170180109
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  • 5
    Electronic Resource
    Electronic Resource
    Thermotropic polyester carbonates. II. Polyester carbonates as high performance fibers (1988)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 36 (1988), S. 805-817 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The fiber spinning and heat treatments of spun fibers from thermotropic polyester carbonates are described. Thermotropic polyester carbonates derived from t-butylhydroquinone, methylhy-droquinone, diphenyl terephthalate, and diphenyl carbonate in the molar ratios of 50 : 50 : 55 : 45; 50 : 50 : 57.5 : 42.5; can be spun successfully, and after proper heat treatment, yield fibers with tenacity as high as 20 g/denier. Normally the best spinning temperature is 10-20°C above melting.
    Additional Material: 8 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1988.070360406
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  • 6
    Electronic Resource
    Electronic Resource
    Thermotropic polyester carbonates. III. Thermotropic polyester carbonates as self-reinforced plastics (1988)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 36 (1988), S. 819-827 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Thermotropic polyester carbonates derived from t-butylhydroquinone, methylhydroquinone, diphenyl terephthalate, and diphenyl carbonate in the molar ratio of 50 : 50 : 55 : 45; 50 : 50 : 57.5 : 5 : 42.5 and 50 : 50 : 60 : 40 can be injection molded successfully from temperatures 10°C below melting to 30-40°C above melting. Normally the best molding temperatures are 10-20°C above melting. If the molding conditions are controlled properly, tensile strengths as high as 1.8 × 104 psi, tensile moduli as high as 7.4 × 105 psi, and flex moduli as high as 1.1 × 106 psi can be obtained.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1988.070360407
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    Paper (German National Licenses)
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