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  • 1
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 29 (1958), S. 257-274 
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The kinetics of polymerization of vinylene carbonate have been studied as a function of the concentration of initiator, the concentration of monomer, and the temperature. In acetone solution, the order of reaction with respect to the concentration of initiator is equal to 0.5, independent of the monomer concentration ((M) = 4.15 and 14.7 mole/l.); moreover any thermal polymerization is absent at 70°C. Contrary in ethylbenzoate ((M) = 3.41 mole/l. at 77°C.) the apparent order with respect to the initiator is 0.77; in agreement with the results of Scanlan in the case of vinylacetate. This behavior is interpreted on the basis of an efficiency factor q, corresponding to the fraction of solvent radicals able to reinitiate a growing chain. In ethylbenzoate solution this factor q is equal to 0.45 and 0.80 for vinylene carbonate and vinylacetate, respectively. With respect to the monomer concentration, the order of the reaction is 1 in the presence of ethylene carbonate as solvent over the total range of concentrations. The transfer constant with this solvent is negligible because it results from molecular weight determinations at constant initiator concentration. In acetone and in benzene the apparent order of reaction is 1, only in dilute solutions; in concentrated solutions small amounts of solvent cause a strong decrease of the rates of reactions. This behavior has been interpreted on the basis of a general kinetic scheme, in which the cross-termination rate constant Φ and the chain transfer constant with the solvent are the predominant factors. In ethylbenzoate the reaction is characterized by a partial degradative chain transfer. The overall activation energy of the polymerization of vinylene carbonate is 22.2 kcal./mole and the coefficient A of the Arrhenius equation is equal to 3.0 × 10-9.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 60 (1962), S. S26 
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 20 (1956), S. 537-550 
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Several problems in the process of radical polymerization, e.g., the relation between the chemical structure of vinyl monomer and its chemical reactivity, the prevalence of head-to-tail configuration, the reactivity of initiator radicals, the alternation tendency in heteropolymerization, and the relative ease of coupling in several cases of homopolymerization, are treated by the theory previously proposed by the present authors, in which reactivity is represented by the magnitude of stabilization energy due to π conjugation between a monomer and a radical in the transition state. In addition, a brief discussion on the existing theories of reactivity and some applications of Hush's method to the problem of termination are presented. The agreement between results of calculation and experiment is shown to be almost statisfactory.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Letters Edition 17 (1979), S. 29-31 
    ISSN: 0360-6384
    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
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  • 5
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 20 (1976), S. 967-974 
    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: In order to extend the application of grafting for the modification of natural polymers, the graft polymerization of methyl methacrylate onto gelatin by radical initiators was studied in aqueous solution at temperatures between 60°C and 80°C. Among the initiators used (peroxy-sulfates, α,α′-azobisisobutylonitrile, and benzoyl peroxide), potassium peroxysulfate was found to be the most efficient initiator in this particular graft polymerization. From the kinetic data with this initiator, it was shown that (1) efficiency of grafting is higher at lower temperature; (2) a sharp increase in the efficiency of grafting occurs at the later period of the polymerization at high temperature, which is attributable to the combination between homopolymer and backbone gelatin; and (3) generally, the number of branches was small and the molecular weight of the branch polymer was high in this polymerization.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 34 (1987), S. 2747-2756 
    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: A series of p-dimethylaminobenzylidene derivatives was able to sensitize the photodecomposition of diphenyliodonium salt to afford highly photosensitive negative-type resins. When a polymer-bearing methacryloylated group in the side chain was sensitized with a combination of the p-dimethylaminobenzylidene compounds and the iodonium salt, the polymer demonstrated high sensitivity even to 488 nm light emitted from an Argon laser. The same photoinitiator systems were applicable to insolubilize poly(glycidyl methacrylate) through cationic photopolymerization. The storage stability of these types of photoinitiators depends on the structure of the benzylidene compounds; decreasing the basicity of the amino group enhanced the thermal stability.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 18 (1974), S. 3633-3651 
    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: Three kinds of trapped radicals are observed in poly(maleic anhydride) (Poly-MAH) which were prepared by the use of radical initiators such as AIBN or BPO. It was found that these radicals were transformed to the active species so as to initiate the cationic polymerization. The structure of these radicals was studied by the ESR and the kinetic analysis of MAH polymerization in the presence of various additives.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
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  • 8
    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 cationic polymerization of 1,2-butylene oxide initiated by radical catalysts has been investigated in detail in the presence of maleic anhydride. The active species of this ionic polymerization was thought to be a conjugated radical of poly(maleic anhydride).
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 9
    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: In a previous paper1 it was mentioned that trapped radicals in poly(maleic anhydride) (Poly-MAH) have the ability to initiate cationic polymerization. In this paper, the cationic polymerization of isobutyl vinyl ether (IBVE) is described using Poly-MAH as the initiator. These radicals show different behavior during polymerization depending upon their structure. In particular, large conjugated radicals initiate ionic polymerizations.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 29 (1991), S. 1197-1202 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monodisperse microspheres of poly(diethylene glycol dimethacrylate) with diameters in the size range 0.4-4.8 μm were prepared by the radiation-induced polymerization. Effects of solvent viscosity and monomer solubility were investigated for various kinds of solvents. The number of the nuclei, produced in the early stage of the polymerization, was found to be constant during the remainder of the polymerization. The nuclei grow to be monodisperse polymer particles without aggregation. This is attributed to the low mobility of the growing polymer particles.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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