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  • Polymer and Materials Science  (16)
  • anionic  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 24 (1986), S. 1675-1683 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The polymerizability of a variety of mono- and multi- nitriles in the presence of free radical initiators at high temperature is determined by the concentration of available cyano-groups. Mononitriles do not polymerize, but multinitriles do so readily. If alkyl substituents are introduced in a molecule that easily polymerizes, this concentration and the ability to polymerize are lowered; if several or bulky substituents are introduced, the polymerization is completely prevented. Multinitriles containing ester groups undergo decarbomethoxylation in these polymerizations. The polymers are black and highly insoluble. From the few reactions that were attempted on these polymers, we can conclude that the structure is probably not the simple conjugated imine structure proposed by earlier investigators, but more experiments are needed to prove this point. The black polymers had conductivities less than 10-9 Ω-1 but, after heating at 700°C, conductivities in the range from 10-3 to 10-6 Ω-1 are observed.
    Additional Material: 3 Tab.
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  • 2
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 28 (1990), S. 551-558 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Six new gem-dicyanocyclobutanes containing carbomethoxy and hydroxyl/acetoxy functions were synthesized by cycloaddition of the appropriate vinyl ethers or alkoxystyrenes to methyl β,β-dicyanoacrylate. They proved to be too thermally labile to allow polycondensation to potentially piezoelectric linear polyesters.
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  • 3
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 28 (1990), S. 1781-1791 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New electrophilic derivatives of maleic anhydride were synthesized to test their reactivity in ene reactions with the terminal double bond of hydrocarbon polymers. The methyl ester and new ethyl ester of sulfomaleic anhydride (SMA) were reacted with 2,2,4-trimethyl-1-pentene 3, which is a model compound for the end group of the hydrocarbon polymers. The SMA esters were more oleophilic than SMA itself, but many side reactions occurred. Higher alkyl esters of SMA could not be synthesized. Two silyl esters of SMA, trimethylsilyl and t-butyldiphenylsilyl, were also synthesized and reacted with 3; ene reactions proceeded well in bulk, but the ene adducts decomposed upon heating. The powerful dienophilic character of these SMA esters was demonstrated by a series of [4 + 2] cycloadditions.
    Additional Material: 1 Tab.
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  • 4
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 30 (1992), S. 2321-2332 
    ISSN: 0887-624X
    Keywords: polyarylate ; pyrolysis ; thermal decomposition ; color ; phenols ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Thermal decompositions and pyrolyses of p-tert-butylphenol, 4,4'-isopropylidenediphenol (BPA), and their acetate and pivalate esters as model compounds for the polyarylate synthesis have been performed. Acetate esters decompose chiefly into phenols and ketene. Pivalate esters, unable to form ketene, are more stable. Acetates and pivalates undergo homolytic cleavage both at ester and alkyl groups. Styrene derivatives stabilize acetate esters, considerably reducing the amount of phenol formed during the decomposition. No intensely colored aromatic compounds were found, although this result is probably an artifact of the methods used. From this study we conclude that ketene is one source of colored materials during polyarylate synthesis. © 1992 John Wiley & Sons, Inc.
    Additional Material: 4 Tab.
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  • 5
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 24 (1986), S. 955-964 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alternating copolymers of styrene (St) with electron-deficient olefins trisubstituted or tetrasubstituted with cyano and carboalkoxy groups have been subjected to 60Co γ-radiolysis together with a series of copolymers of methyl methacrylate (MMA) and St. The chain scission susceptibility Gs - Gx determined by membrane osmometry drastically decreases as St is incorporated in poly(methyl methacrylate) (PMMA). Whereas the alternating St-MMA copolymer is slightly crosslinked upon irradiation, an alternating copolymer of St with diethyl 2-cyano-1,1-ethylenedicarboxylate maintains a fairly high degradation sensitivity (Gs - Gx = 1.2). The reactive-ion etch rates were determined for the series of polymers in CF4/O2 (92/8). The etch resistance is significantly increased by introduction of St units in PMMA, and the highly substituted alternating copolymer etches as slowly as the MMA(50) - St(50) copolymers. Thus the alternating copolymer of NCCH=C(CO2Et)2 with St behaves like PMMA when exposed to high-energy radiation but is comparable to PSt in plasma environments.
    Additional Material: 6 Ill.
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  • 6
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 27 (1989), S. 2871-2881 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alternating copolymers of styrene with β-carboalkoxy-substituted t-butyl α-cyanoacrylates undergo facile deesterification at 150-190°C, about 60°C below the deprotection temperature of poly(t-butyl methacrylate), and decarboxylation at 170-200°C. When the β-substituent is a methyl ester, the two events are clearly separated, with the deesterification occurring at a maximum rate at 165°C and decarboxylation at 193°C. Anhydride formation is negligible in this case. The copolymer with t-butyl cyanofumarate exhibits simultaneous deesterification and decarboxylation events at 180°C with concomitant minor dehydration.
    Additional Material: 5 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 30 (1992), S. 2341-2347 
    ISSN: 0887-624X
    Keywords: piezoelectric ; pyroelectric ; cyano-containing copolymers ; methyl vinylidene cyanide ; Lewis acid ; acrylonitrile ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of a series of novel cyano-containing copolymers is described. Alternating copolymers of acrylonitrile with vinyl esters are obtained by increasing the electrophilic character of the nitrile monomers by complexation with zinc chloride. Copolymers of methyl and ethyl α-cyanoacrylates with vinyl esters are prepared using radical initiators in the presence of 7% acetic acid as inhibitor for anionic polymerization. The copolymers of methyl α-cyanoacrylate with the vinyl esters have Tg's above 140°C. Methyl vinylidene cyanide (MVCN) copolymerizes spontaneously with para-substituted styrenes to yield copolymers with high inherent viscosities and high Tg (160°C) and the copolymer of MVCN with vinyl acetate is also synthesized. The pyroelectric constants p for these polymers were measured and the values of p for the copolymers of vinyl acetate with methyl β,β-dicyanoacrylate, methyl α-cyanoacrylate, or MVCN were in the same range as the well-studied vinylidene cyanide/vinyl acetate copolymer. A higher concentration of dipoles generally results in higher Tg's and higher pyroelectric coefficients. © 1992 John Wiley & Sons, Inc.
    Additional Material: 4 Tab.
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  • 8
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2787-2792 
    ISSN: 0887-624X
    Keywords: 4-vinylpyridine ; zinc ; complexes ; spontaneous ; copolymerization ; electron-rich ; monomers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The spontaneous copolymerization of 4-vinylpyridine (4-VP) complexed with three different zinc salts (chloride, acetate, and triflate) with various electron-rich vinyl monomers (p-methoxystyrene, MeOSt; p-methylstyrene, MeSt; α-methylstyrene, α-MeSt; p-tert-butylstyrene, BuSt; styrene, St) was investigated in methanol at 75°C. Increasing the zinc salt concentration or the nucleophilicity of the electron-rich monomer increased the copolymer yields. All obtained copolymers are characterized by high molecular weight (105) and broad molecular weight distribution. Both 1H-NMR and elemental analyses confirmed the almost 1 : 1 copolymer structure. Changing the anion of the zinc salt does not have a considerable effect either on the copolymerization rate or on the molecular weight. The proposed mechanism exhibits the formation of a σ-bond between the β-carbons of the two donor-acceptor monomers. This creates the 1,4-tetramethylene biradical intermediate which can initiate the copolymerization reaction. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2787-2792, 1997
    Additional Material: 2 Tab.
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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. 1673-1679 
    ISSN: 0887-624X
    Keywords: polyaniline ; acylation ; alkylation ; solubility ; conductivity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Various alkylating and acylating agents, with different electrophilicity, were allowed to react with polyaniline “emeraldine base” (Pan-EB) or its anion. Replacing the N-hydrogens of polyaniline by various acyl or benzyl groups strongly affected the solubility and the electrical conductivity of the polymer. Neutral Pan-EB was reacted with benzoyl chloride, p-t-butylbenzoyl chloride or pivaloyl chloride in N,N′-dimethylpropylene urea (DMPU) solutions. While the benzoyl and pivaloyl derivatives showed very poor solubility in common organic solvents, the p-t-butylbenzoyl derivative was readily soluble in THF, chloroform, DMSO, etc. As expected, these acyl derivatives showed diminished electrical conductivity relative to that of the parent Pan-EB. Benzyl chlorides did not react with neutral Pan-EB. Attempts to prepare solutions of the nitrogen anion of Pan-EB by reaction with sodium hydride in DMSO or DMPU led invariably to crosslinked insoluble material. This was ascribed to Michael addition of the formed nitrogen anions to the quinonimine moieties. However forming the nitrogen anion in presence of p-t-butylbenzyl chloride trapped it to form N-benzylated Pan-EB. This was a soluble high molecular weight, electrically conductive (4.3 × 10-1 S cm-1 as the hydrochloride) N-alkyl Pan-EB. Reacting Pan-EB with excess of both sodium hydride and benzyl chlorides led to film-forming per-benzylated Pan-leucoemeraldine reduced form. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1673-1679, 1997
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  • 10
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 2703-2710 
    ISSN: 0887-624X
    Keywords: N-cyanomethanimine ; homopolymerization ; copolymerization ; anionic ; free radical ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New imine monomers containing C-aryl and N-cyano substituents were synthesized and polymerized by both radical and anionic initiation. Homopolymerization yielded low molecular weight polymers (Mn 〈 2100). Higher yields were obtained with anionic initiation rather than radical initiation. Radical initiated copolymerization with p-methoxystyrene gave low yields of low molecular weight copolymers. Radical initiated copolymerization with methyl acrylate gave copolymers of 15,000-,32,000 molecular weight in moderate yields, but with rather low incorporation of the imine monomer. The C-substituent affected the anionic and free radical reactivity similarly. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2703-2710, 1997
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