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  • 1
    Electronic Resource
    Electronic Resource
    Polyarylates. II. The molecular weight distribution measured by GPC (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 1709-1712 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1987.080250623
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  • 2
    Electronic Resource
    Electronic Resource
    Polyarylates. III. Kinetic studies of interfacial polycondensation (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 2195-2206 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of interfacial polycondensation of bisphenol A with isophthaloyl chloride and terephthaloyl chloride in dichloromethane with triethylbenzylammonium chloride (TEBAC) as the catalyst was investigated via measurements of bisphenolate concentration by UV. The reaction was found to be second order with respect to bisphenolate. The dependence of the rate constant on stirring speed, amount of TEBAC, and reaction temperature was studied. The rate constant was increased with an increase of stirring speed, quantity of TEBAC added, as well as the reaction temperature. The activation energy was found to be 7.7 kcal/mol at a stirring speed of 700 rpm in the presence of 0.160 of TEBAC. The role of TEBAC was found to be interesting. It did not alter the equilibrium (the partition coefficient remained the same in the presence of TEBAC), but it did enhance the transfer rate of bisphenolate.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1987.080250816
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  • 3
    Electronic Resource
    Electronic Resource
    Molecular composite. II. Novel block copolymer and semi-interpenetrating polymer network of rigid polyamide and flexible polyimide (1994)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 32 (1994), S. 2629-2639 
    Details
    ISSN: 0887-624X
    Keywords: molecular composite ; liquid-crystalline polymer ; lyotropic polyamide ; polyimide ; semi-interpenetrating polymer network ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2,2'-Dimethyl-4,4'-diamino-biphenyl was used to prepare a lyotropic amine-terminated polyamide (PBTA) prepolymer with terephthaloyl dichloride, and an amide oligomer with reactive endcaps of maleimide, respectively. The former was employed in an attempt to increase the solubility of PA/PI block copolymers, and the latter to produce a three-dimensional (isotropic) reinforced molecular composite through the technology of a semiinterpenetrating polymer network (semi-IPN). PBTA prepolymer was copolymerized with an amine-terminated polyimide via a coupling reaction using terephthaloyl dichloride. The resultant block copolymers were characterized by IR, NMR, ηinh and GPC to confirm that the copolymerization reaction was precisely accomplished, as well as to determine their composition and molecular weight. Thermal analysis and lyotropic behavior were also studied for these copolymers. Rigid-rod amide oligomer was crosslinked in the presence of another flexible polyimide. Five sets of semi-IPN films were prepared under varying compositions. The curing conditions were investigated by DSC; in addition, the cured semi-IPNs exhibited a single phase (1 Tg) according to examination by an instrument for thermally stimulated current (TSC). No large-scale phase separation was observed in SEM images of the fractured surfaces. © 1994 John Wiley & Sons, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1994.080321404
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  • 4
    Electronic Resource
    Electronic Resource
    Polyarylates. V. The influence of phase transfer agents on the interfacial polycondensation (1988)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 26 (1988), S. 2039-2046 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effect of various phase transfer agents on the interfacial polycondensation of bisphenol A with isophthaloyl chloride was investigated. It was found that the transfer rate of bisphenolate and, thus, the reaction rate of polycondensation were increased with an increasing lipophilicity of the phase transfer agent, i.e. TBAC 〉 TEBAC 〉 TEAC, whereas the equilibrium of bisphenolate between the organic phase and the aqueous phase was hardly affected. Moreover, experimental evidence indicated that a phase transfer agent of high lipophilicity reduced the hydrolysis of the acid chloride, an important aspect in interfacial polycondensation.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1988.080260805
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  • 5
    Electronic Resource
    Electronic Resource
    Synthesis and characterization of polyimides based on novel tricyclo[6,2,2,02,7] dianhydride (1990)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 28 (1990), S. 3347-3362 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 3-Phenyl-tricyclo [6,2,2,02,7]dodeca-2,11-ene-5,6,9,10-tetracarboxylic dianhydride was prepared from 1,1-diphenyl ethylene and maleic anhydride in 1 : 2 mole ratio by [4 + 2]π Diels-Alder cycloaddition. The structure of the dianhydride was determined by mass spectroscopy, IR, 1H-NMR, elemental analyses, and single crystal x-ray diffraction. The monomer was condensed with several diamines in N-methyl pyrrolidone or m-cresol. The polyamic acids and the polyimides synthesized had inherent viscosities in the range of 0.19-0.31 and 0.17-0.25 dL/g, respectively, measured in N-methyl pyrrolidone at 30°C. Both the polyamic acids and the polyimides were found to be soluble in m-cresol, N-methyl pyrrolidone, dimethylacetamide, dimethyl formamide, and dimethyl sulfoxide. The polymides showed a low degree of crystallinity from wide angle x-ray diffraction. Thermal analysis of these polyimides revealed that their glass transition temperatures (Tg) were in the 215-237°C range and they decomposed in two stages. The first-stage decomposition temperatures were almost the same in O2 or N2 atmospheres, but the polymers showed a better thermal stability in O2 rather than in N2 in the second stage. The mechanism of thermal degradation is discussed.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1990.080281214
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  • 6
    Electronic Resource
    Electronic Resource
    Thermal degradation of polymethacrylic acid (1992)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 30 (1992), S. 2389-2397 
    Details
    ISSN: 0887-624X
    Keywords: polymethacrylic acid ; thermal degradation ; kinetics ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal degradation of polymethacrylic acid was found to have two separate decomposition regions. The first decomposition region, due to anhydride formation primarily, was caused by the conversion of polymethacrylic acid to polymethacrylic anhydride. This reaction followed first-order kinetics and had an activation energy of 40.5 kcal/mol. The second decomposition region was the thermal degradation for the corresponding polymethacrylic anhydride. In this region, the fragmentation of anhydride rings structure in polymethacrylic anhydride constitutes the major decomposition reaction with an activation energy of 37.4 kcal/mol. © 1992 John Wiley & Sons, Inc.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1992.080301113
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  • 7
    Electronic Resource
    Electronic Resource
    Polyarylates (I): Investigation of the interfacial polycondensation reaction by UV (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 1505-1515 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The interfacial polycondensation of bisphenol A with isophthaloyl chloride and terephthaloyl chloride in dichloromethane with triethylbenzylammonium chloride as the catalyst was described. A well-defined two-phase system had been observed, so the concentration of bisphenolate in the aqueous phase could be determined by UV spectrometer. The conversion was found to increase rapidly with reaction time, but the rate of increase in molecular weight was slow. At the initial stage with conversion up to 95%, the reaction proceeded similarly to that of solution polycon-densation because the synthesized polyarylate could be dissolved in dichloromethane, and a polymer with a low molecular weight resulted. At the final stage of the reaction, the molecular weight was increased to a very high value due to the local concentration effect. The mole ratio of bisphenol A to diacid chlorides was found to affect the molecular weight very much. In the case of a mole ratio less than 1, the reaction remained in the initial stage mostly, and the molecular weight was low. However, for a mole ratio greater than 1, polyarylate with a very high molecular weight could be obtained because the local concentration effect was much more significant owing to the high concentration of bisphenolate that remained in the aqueous phase at the final stage.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1987.080250605
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  • 8
    Electronic Resource
    Electronic Resource
    Polyarylates. IV. Synthesis of block copolymers via two-step interfacial polycondensation (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 3405-3412 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new method for preparing block copolyarylates via two-step interfacial polycondensation is proposed. First, oligomers with acid chloride end groups were obtained from interfacial polycondensation with a mole ratio of bisphenol A to diacid chloride(s) less than I. In the second step, two reaction systems containing various oligomers were mixed thoroughly and more bisphenolate was charged into this mixture. The synthesis of the block copolyarylates was justified from the viewpoint of statistics, and of differences in molecular weight between oligomers and block copolymers. These block copolyarylates could be differentiated from polyarylates through crystal-line behavior and solubility in m-cresol analyses.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1987.080251220
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  • 9
    Electronic Resource
    Electronic Resource
    Synthesis, characterization, and kinetics studies of organic soluble photosensitive copolyimide (1989)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 27 (1989), S. 1481-1497 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A copolyimide synthesized from 3,3′,4,4′-benzophenone tetracarboxylic dianhydride, 3,5-diaminobenzoic acid, and 2,3,5,6-tetramethyl-p-phenylene diamine was found to be soluble in N-alkyl substituted amides. An organic soluble photosensitive polyimide was obtained by further reaction of the copolyimide with methacrylic acid glycidyl ester. After adding Michler's ketone, the UV spectra absorbance near 360 nm of the copolyimide decreased rapidly upon the irradiation of mercury lamp. Using benzoic acid and methacrylic acid glycidyl ester as model compounds and N, N-dimethylbenzylamine as catalyst, the mechanism of reaction between the carboxylic group of the copolyimide and epoxy group of methacrylic acid glycidyl ester in N-methyl-2-pyrrolidone was found to have two competitive reactions, namely the auto-catalytic and the catalytic reactions. The apparent rate constants of each reaction were determined. Comparison of apparent rate constants between the model compound and the polymer reaction system are also reported.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1989.080270503
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  • 10
    Electronic Resource
    Electronic Resource
    Molecular composite. I. Novel block copolymers of liquid-crystalline polyamide and amorphous polyimide: Synthesis and characterization (1993)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 31 (1993), S. 2775-2784 
    Details
    ISSN: 0887-624X
    Keywords: molecular composite ; liquid-crystalline polymer ; block copolymer ; lyotropic polyamide ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Two series of PA/PI block copolymers have been prepared from a two-pot polycondensation reaction. Acid-terminated poly-p-benzamide (PBA) prepolymer, composed of a rigid-rod structure and lyotropic character, was synthesized by applying the phosphorylation reaction of Yamazaki. On the other hand, two amine-terminated polyimide prepolymers with an amorphous structure were prepared by a typical low-temperature condensation reaction from 4,4′-(hexafluoroisopropylidene)-bis(phthalic anhydride) (6FDA)/2,2′-bis-(4-aminophenyl)-hexafluoropropane (BAAF) and 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA)/2,3,5,6-tetramethyl-p-phenylene diamine (TMPD). The molecular weight of these prepolymers was determined by intrinsic viscosity or GPC. The copolymerization was carried out by mixing two prepolymer solutions. The products were analyzed by extraction, IR, and ηinh so as to confirm that the copolymerization reaction was precisely accomplished. Thermal analysis and lyotropic behavior were studied for these block copolymers and the critical concentration in NMP-LiCl was found to be 6.0% for one among those block copolymers. The copolymers were observed to form anisotropic liquid-crystalline domains under polarized light once the solutions had been prepared at (and beyond) the critical concentration. © 1993 John Wiley & Sons, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1993.080311114
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