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  • 1
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 33 (1995), S. 1059-1067 
    ISSN: 0887-624X
    Keywords: radical polymerization ; methyl trans-β-vinylacrylate ; kinetics propagation radical ; monomer reactivity ratios ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Methyl trans-β-vinylacrylate (MVA) undergoes radical polymerization with α,α′-azobis(isobutyronitrile) (AIBN) in bulk and solution. The polymer obtained consists of 85% trans-1,4 and 15% trans-3,4 units. Poly(MVA) (PMVA) is readily soluble in common organic solvents, but insoluble in n-hexane and petroleum ether. PMVA exhibits a glass transition at 60°C, and loses no weight up to 300°C in nitrogen. The kinetics of MVA homopolymerization with AIBN was investigated in benzene. The rate of polymerization (Rp) can be expressed by Rp = k[AIBN]0.5[MVA]1.0, and the overall activation energy has been calculated to be 94 kJ/mol. The propagation radical of MVA at 80°C was detected by ESR spectroscopy, which indicated that the unpaired electron of the propagating radical was completely delocalized over the three allyl carbons. Furthermore, the steady-state concentration of the propagating radical of MVA at 60°C was determined by ESR spectroscopy, and the propagation rate constant (kp) was calculated to be 1.25 X 102 L/mol ·s. Monomer reactivity ratios in copolymerization of MVA (M2) with styrene (M1) are r1 = 0.16 and r2 = 4.9, from which Q and e values of MVA are calculated as 4.2 and -0.32, respectively. © 1995 John Wiley & Sons, Inc.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 371-376 
    ISSN: 0887-624X
    Keywords: poly(arylene ether ether ketone) ; photoreactive polymer ; nucleophilic substitution ; photosensitivity ; contrast ; negative type ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Isopropyl substituted poly(phenylene ether ether ketone) with a high molecular weight was prepared by nucleophilic substitution reaction of isopropyl-substituted difluoro diaryl ether with hydroquinone. This polymer was amorphous and soluble in common organic solvents, such as THF, chloroform, and cyclohexanone. Thermogravimetry of the polymer showed good thermal stability, indicating that a 10% weight loss of the polymer was observed at 470°C in nitrogen. The glass transition temperature of the polymer was 145°C. The polymer had a broad UV absorption band over 250-380 nm. The polymer acted as a photosensitive resist of negative type for UV radiation. The resist had a sensitivity of 40 mJ/cm2 and a contrast of 2.8, when it was developed with DMF at room temperature. © 1997 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2259-2266 
    ISSN: 0887-624X
    Keywords: poly(m-phenylene) ; selective coupling ; regiocontrolled polymer ; oxidative coupling polymerization ; thermal stability ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(4,6-di-n-butoxy-1,3-phenylene) (6) was prepared by oxidative coupling polymerization of 1,3-di-n-butoxybenzene (1) or 2,2′,4,4′-tetra-n-butoxy biphenyl (3). Polymerizations were conducted in nitrobenzene in the presence of FeCl3 at room temperature and produced polymers with number-average molecular weights up to 42,000. The effects of various factors, such as amount of FeCl3 and reaction temperature and time were studied. The structure of polymer 6 was characterized by 270 MHz 1H- and 68.5 MHz 13C-NMR spectroscopies and was estimated to consist of almost completely 1,3-linkage. The regiocontrolled polymer was readily soluble in common organic solvents. Thermogravimetric analysis of polymer 6 showed 10% weight loss at 390°C in nitrogen. © 1997 John Wiley & Sons, Inc. J Polym Chem 35: 2259-2266, 1997
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 0887-624X
    Keywords: photosensitive polyimide ; highly dimensional stability ; low dielectric constant ; poly(amic acid) ; diazonaphthoquinone ; positive type ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A positive-working photosensitive polyimide precursor based on fluorinated poly(amic acid) (FPAA) and 2,3,4-tris(1-oxo-2-diazonaphthoquinon-4-ylsulfonyloxy)benzophenone (D4SB) as a photosensitive compound has been developed. FPAA was prepared by ring-opening polyaddition of dianhydrides, pyromellitic dianhydride and biphenyltetracarboxylic dianhydride, with diamine, 2,2′-bis(trifluoromethyl)benzidine, in methanol. The FPAA film showed excellent transparency to UV light and good solubility in a wide range of organic solvents. The dissolution behavior of FPAA containing 30 wt % D4SB after exposure was studied, and it was found that the difference of dissolution rate between exposed and unexposed parts was enough to get high contrast due to the photochemical reaction of D4SB in the polymer film. The photosensitive fluorinated polyimide (FPI) precursor containing 30 wt % D4SB showed a sensitivity of 80 mJ cm-2 and a contrast of 7.8 with 365 nm light when it was developed with 0.3% aqueous tetramethyl ammonium hydroxide solution at room temperature. The FPI film cured up to 360°C had a low coefficient of thermal expansion of 10.3 ppm °C-1 and a low dielectric constant of 3.04. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2261-2267, 1998
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2267-2272 
    ISSN: 0887-624X
    Keywords: poly(arylene ether)s ; pendant benzoyl groups ; polyxanthenes ; Friedel-Crafts cyclization ; thermal stability ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(arylene ether)s (3), (4) containing pendant benzoyl groups as precursors for novel polyxanthenes (7), (8) were prepared by nucleophilic substitution reaction of 2,5-difluoro-4-benzoylbenzophenone (1) or 2,5-difluoro-4-(4-dodecylbenzoyl)-4′-dodecylbenzophenone (2) with hydroquinone derivatives in the presence of potassium carbonate in N,N-dimethylacetamide. The polycondensation proceeded smoothly at 165°C and produced poly(arylene ether)s with inherent viscosities up to 0.80 dL/g. The novel polyxanthenes were synthesized via the reduction of poly(arylene ether)s followed by the Friedel-Crafts cyclization of diol polymers. The structure of the polyxanthenes was characterized by 1H-NMR and IR spectroscopies. Polyxanthene 8 was quite soluble in chloroform and THF. The 10% weight loss temperature of polyxanthene 7 was 510°C in nitrogen and it was 90°C higher than the corresponding poly(arylene ether) 3. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2267-2272, 1997
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 413-419 
    ISSN: 0887-624X
    Keywords: liquid crystalline polymer ; polyarylates ; 4-hydroxy-2,3,5,6-tetrafluorobenzoic acid ; 6-hydroxy-2-naphthoic acid ; fine structure ; thermal property ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 4-Hydroxy-2,3,5,6-tetrafluorobenzoic acid/6-hydroxy-2-naphthoic acid copolymers (FHBA/HNA copolymer) with different copolymer compositions were prepared and the influence of FHBA residue on the thermal properties and structures of the copolymers were investigated. Introduction of FHBA decreased the crystal/nematic phase transition temperatures(TCNs) of the FHBA/HNA copolymers. TCNs of the copolymers were in the temperature range between 200 and 250°C, depending on the copolymer composition. They are approximately 40°C lower than those of 4-hydroxybenzoic acid/HNA copolymers. FHBA/HNA copolymers exhibited low crystallinity, and annealing treatment hardly influenced the crystalline natures. FHBA residue possibly interferes with the recrystallization during annealing. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 413-419, 1998
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 36 (1998), S. 2309-2314 
    ISSN: 0887-624X
    Keywords: direct polycondensation ; ordered polymer ; polyamide ; condensing agent ; steric effect ; nonsymmetric monomer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The ordered (-aacdbbdc-) polymer was prepared by the direct polycondensation of a pair of symmetric monomers (XabX), 4,4′-(oxydi-p-phenylene)dibutanoic acid (XaaX) and 2-methoxyisophthalic acid (XbbX), with a nonsymmetric monomer (YcdY), 4-aminobenzhydrazide, using the condensing agent diphenyl (2,3-dihydro-2-thioxo-3-benzoxazolyl)phosphonate (1). The polymerization was carried out by a one-pot procedure, that is, mixing the dicarboxylic acids, condensing agent 1 and triethylamine in NMP for 2 h at room temperature, followed by the addition of 4-aminobenzhydrazide. This polymerization proceeded smoothly, yielding the ordered polymer with an inherent viscosity of 0.34 dL g-1. The microstructure of the ordered polymer was confirmed by comparing the authentic ordered polymer in their 13C-NMR spectrum. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2309-2314, 1998
    Additional Material: 3 Ill.
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  • 8
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 34 (1996), S. 109-115 
    ISSN: 0887-624X
    Keywords: poly(ether ether ketone) ; photoreactive polymer ; nucleophilic substitution ; electrophilic substitution ; photosensitivity ; contrast ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(ether ether ketone)s containing alkyl groups were prepared by nucleophilic substitution reaction of alkyl-substituted difluoro diaryl ethers with hydroquinone or by electrophilic substitution reaction of alkyl-substituted diaryl ether with 4,4′-oxydibenzoic acid in PPMA. Polycondensations proceeded smoothly and produced polymers having inherent viscosities up to 0.5--1.6 dL/g. The polymers were quite soluble in strong acid, dipolar aprotic solvents, and chloroform at room temperature. Thermogravimetry of the polymers showed excellent thermal stability, indicating that 10% weight loses of the polymers were observed in the range above 450°C in nitrogen atmosphere. The glass transition temperatures of the polymers ranged from 128 to 146°C. Furthermore, Polymer 3b functioned as a photosensitive resist of negative type for UV radiation. The resist had a sensitivity of 42 mJ/cm2 and a contrast of 2.5, when it was postbaked at 100°C for 10 min, followed by development with THF/acetone at room temperature. © 1996 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
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  • 9
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 605-611 
    ISSN: 0887-624X
    Keywords: poly(arylene ether)s ; pendant benzoyl groups ; 2,5-difluoro-4-benzoyl-benzophenone ; hydroquinone derivatives ; thermostability ; semi-crystalline polymer ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Poly(arylene ether)s (3) containing pendant benzoyl groups were prepared by the aromatic substitution reaction of 2,5-difluoro-4-benzoylbenzophenone (2) with hydroquinone (1a) and methylhydroquinone (1b) in the presence of potassium carbonate in N,N-dimethylacetamide. The polycondensation proceeded smoothly at 165°C and produced poly(arylene ether)s with inherent viscosities up to 0.8 dL/g. The polymer (3b) derived from methylhydroquinone was quite soluble in common organic solvents and could be processed into uniform films from solutions. On the other hand, the polymer (3a) derived from hydroquinone was only soluble in pentafluorophenol and methanesulfonic acid and had a high crystallinity. These polymers showed 10% weight losses at around 420 and 490°C in nitrogen. Polymer 3b also showed good tensile strength and tensile moduli. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 605-611, 1997
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Macromolecular Rapid Communications 16 (1995), S. 469-475 
    ISSN: 1022-1336
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Poly[2-(tert-butoxycarbonyl)-1,4-phenylene] (2) was prepared by the Ni-catalyzed polymerization of tert-butyl 2,5-dichlorobenzoate (1). The microstructure of polymer 2 was probably alternating head-to-head and tail-to-tail. This polymer was soluble in dipolar aprotic solvents, chloroform, tetrahydrofuran, and dichloromethane. Polymer 2 was saponified easily by thermal or acid treatment to yield poly[2-carboxy-1,4-phenylene] (3). Decarboxylation of polymer 3 in quinoline in the presence of copper(II) oxide produced poly(p-phenylene) (PPP) (4).
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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