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  • 11
    Electronic Resource
    Electronic Resource
    Iodine-initiated, solid-state copolymerization of tetraoxane with 1,3-dioxolane in the presence of methylal. V. Studies on molecular weight distribution of copolymer (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 23 (1979), S. 3383-3394 
    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 iodine-initiated, solid-state copolymerization of the tetraoxane-1,3-dioxolane-methylal system has been studied by measuring the molecular weight distribution of the copolymer. The molecular weight distribution of the copolymer is found to be strongly dependent on the addition method of the 1,3-dioxolane-methylal solution to tetraoxane. The copolymer obtained by the one-addition copolymerization has a molecular weight distribution curve that shows a very broad distribution, with a discernible shoulder; and the copolymer obtained by the continuous-addition copolymerization has a very sharp curve. Particle size of the copolymer also influences the molecular weight distribution. For the one-addition copolymerization, the larger the particle size of the copolymer, the broader the molecular weight distribution. For the continuous-addition copolymerization, however, the molecular weight distribution is nearly constant regardless of particle size. The dependence of the molecular weight distribution on the polymerization time and the concentrations of iodine, 1,3-dioxolane, and methylal is discussed in detail. These results suggest that this copolymerization system is characterized by a reaction that proceeds from the surface to the center of the tetraoxane crystals.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1979.070231122
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  • 12
    Electronic Resource
    Electronic Resource
    Iodine-initiated, solid-state copolymerization of tetraoxane with 1,3-dioxolane in the presence of methylal. VIII. Mechanical properties of copolymer (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 23 (1979), S. 3421-3426 
    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: Copolymers obtained by the solid-state copolymerization of tetraoxane with 1,3-dioxolane were pelletized using a vent-type extruder and the mechanical properties were measured. The mechanical properties were found to be largely influenced by the distributions of molecular weight and ethylene oxide, which were controlled by the addition method of the 1,3-dioxolane-methylal solution into polymeric system. The mechanical properties of the copolymers were also found to be intermediate between those of Duracon M90 and Delrin 500.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1979.070231125
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  • 13
    Electronic Resource
    Electronic Resource
    Synthesis of cationic flocculant by radiation-induced copolymerization of methyl chloride salt of N,N-dimethylaminoethyl methacrylate with acrylamide in aqueous solution (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 24 (1979), S. 1713-1721 
    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 radiation-induced copolymerization of the methyl chloride salt of N,N-dimethylaminoethyl methacrylate (DMAEM·MC) with acrylamide (AAm) was used to prepare a cationic polymer flocculant. The polymerization rate increased with increasing dose rate, polymerization temperature, monomer concentration and mole fraction of AAm in the monomer mixture. The molecular weight of the copolymer was also found to increase with monomer concentration and mole fraction of AAm, but at high concentration and fraction of AAm, intermolecular crosslinking tends to occur during the polymerization to form water-insoluble copolymer. A water-soluble copolymer having various molecular weights and cationic strengths can be synthesized by selecting suitable reaction conditions; i.e., this radiation process can provide a much higher molecular weight copolymer with a wide range of cationic strength. The flocculation effect was evaluated using sludge from wastewater of sugar manufacture. It was found that the radiation-polymerized copolymer DMAEM·MC-AAm has an excellent flocculation effect.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1979.070240711
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  • 14
    Electronic Resource
    Electronic Resource
    Synthesis of cationic flocculant by radiation-induced copolymerization of methyl chloride salt of N,N-dimethylaminoethyl methacrylate with acrylamide in aqueous solution. II. Copolymerization at higher monomer concentration (1981)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 26 (1981), S. 1585-1594 
    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 radiation-induced copolymerization of methyl chloride salt of N,N-dimethylaminoethyl methacrylate with acrylamide was studied to prepare a polymer flocculant that can be handled as a solid. The product obtained in the presence of 5-20% water was a solid and could be ground to a powder without drying. In order to obtain a water-soluble polymer at a higher concentration, the effect of various additives on the copolymerization was investigated and found that alcohols bearing a hydrogen atom attached to the tertiary carbon atom effectively inhibit intermolecular crosslinking to give water-soluble polymer. It is suggested that the formation of water-insoluble polymer is predominantly attributable to the crosslinking of polymer chains rather than to the imidation of amide groups. Copolymerization in the presence of isopropyl alcohol as inhibitor of the crosslinking was also studied and compared with that reported previously, which was carried out at a lower monomer concentration without additives.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1981.070260514
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  • 15
    Electronic Resource
    Electronic Resource
    Study on radiation grafting of acrylic acid onto fluorine-containing polymers. II. Properties of membrane obtained by preirradiation grafting onto poly(tetrafluoroethylene) (1981)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 26 (1981), S. 3871-3883 
    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: Some properties of the membranes obtained by the preirradiation grafting of acrylic acid onto poly(tetrafluoroethylene) (PTFE) film have been studied. The dimensional change by grafting and swelling, water uptake, electric conductivity, and mechanical properties of the grafted PTFE films were measured and were found to increase as the grafting proceeds. These properties were found to be dependent mainly on the degree of grafting regardless of grafting conditions except higher monomer concentration (80 wt %). The electric conductivity and mechanical properties of the membranes at 80 wt % monomer concentration is lower than those at a lower monomer concentration. The results suggest that the membranes obtained at 80-wt % acrylic acid solution have a somewhat heterogeneous distribution of electrolyte groups as compared with those prepared at a monomer concentration less than 60 wt %. X-ray microscopy of the grafted films revealed that the grafting begins at the part close to the film surface and proceeds into the center with progressive diffusion of monomer to give finally the homogeneous distribution of electrolyte groups. The membranes show good electrochemical and mechanical properties which make them acceptable for the practical uses as cation exchange membrane.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1981.070261132
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  • 16
    Electronic Resource
    Electronic Resource
    Radiation grafting of α,β,β-trifluoroethylenesulfonyl fluoride onto low-density polyethylene film by simultaneous irradiation method. I. Kinetic study of simultaneous-irradiation grafting (1988)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 36 (1988), S. 55-62 
    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: α,β,β-Trifluoroethylenesulfonyl fluoride (TFESF) was grafted onto polyethylene (PE) film by a simultaneous-irradiation method. The influences of the grafting conditions were analyzed kinetically. The dependencies of the grafting rate on the dose rates and monomer concentrations ranging from 10 to 75% were found to be of 1 and 0 order, respectively. The overall activation energy for the graft polymerization was 2.05 × 104 J/mol. The grafting rate was found to be independent of the film thicknesses ranging from 25 to 100 μm.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1988.070360105
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  • 17
    Electronic Resource
    Electronic Resource
    Iodine-initiated, solid-state copolymerization of tetraoxane with 1,3-dioxolane in the presence of methylal. I. Fundamental study on beaker-scale copolymerization (1977)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 21 (1977), S. 711-722 
    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 iodine-initiated, solid-state copolymerization of tetraoxane with 1,3-dioxolane in the presence of methylal has been studied on a beaker scale. It was found that tetraoxane can be easily copolymerized with 1,3-dioxolane by a small amount of iodine as initiator and gives oxymethylene copolymer with excellent thermal stability in a high yield. The copolymerization was largely influenced by the concentrations of iodine, 1,3-dioxolane, and methylal, i.e., the polymerization rate increased with increase not only in iodine but also in 1,3-dioxolane, and the thermal stability and the molecular weight of the copolymer were mainly affected by 1,3-dioxolane and methylal concentration, respectively.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1977.070210312
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  • 18
    Electronic Resource
    Electronic Resource
    Iodine-initiated, solid-state copolymerization of tetraoxane with 1,3-dioxolane in the presence of methylal. VI. Studies on copolymer composition (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 23 (1979), S. 3395-3409 
    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: In order to elucidate the mechanism of copolymerization of tetraoxane-1,3-dioxolane, the consumption rate of 1,3-dioxolane was measured by using gas chromatography, and the copolymer composition was determined by high-resolution NMR spectroscopy and differential scanning calorimetry. It was found that 1,3-dioxolane is rapidly consumed in the early stage of copolymerization if 1,3-dioxolane is added at once. The copolymer thus obtained is characterized by a heterogeneous distribution of 1,3-dioxolane in the copolymer chain. However, if 1,3-dioxolane is added continuously during the progress of the copolymerization, the distribution and content of 1,3-dioxolane in the copolymer chain was found to be very homogeneous.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1979.070231123
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  • 19
    Electronic Resource
    Electronic Resource
    Iodine-initiated, solid-state copolymerization of tetraoxane with 1,3-dioxolane in the presence of methylal. VII. Treatment of copolymer after polymerization (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 23 (1979), S. 3411-3420 
    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 various procedures for removing the residual reactants and impurities from the polymer particle obtained by the solid-state copolymerization of tetraoxane with 1,3-dioxolane have been examined. The removal of the residual reactants by washing with solvents, such as acetone or water, were very difficult, because the residual reactants are mainly located in the central part of the polymerized particle. By evacuation of the polymeric system just after polymerization, however, the residual reactants were found to be easily eliminated from the polymer particle. It was also found that the polymer degradation caused by the acid impurities formed during polymerization can be prevented satisfactorily by neutralization using gaseous ammonia. On the basis of these findings, the simple process for polyoxymethylene production has been achieved; i.e., it was found that the polymer particle including the residual reactants and impurities can be directly pelletized using a vent-type extruder, immediately after the copolymerization procedure and the ammonia gas treatment, to obtain the polyoxymethylene pellet with an excellent thermal stability and a well controlled molecular weight.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1979.070231124
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  • 20
    Electronic Resource
    Electronic Resource
    Radiation grafting of acrylic acid onto fluorine-containing polymers. I. Kinetic study of preirradiation grafting onto poly(tetrafluoroethylene) (1981)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 26 (1981), S. 3117-3124 
    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: Preirradiation grafting of acrylic acid onto poly(tetrafluoroethylene) film was studied. The trapped radicals formed upon irradiation are able to induce graft polymerization under appropriate conditions. The influence of the grafting conditions were analyzed kinetically. The grafting reaction begins close to the film surface and proceeds into the center with progressive monomer diffusion through the grafted layer. The dependences of the grafting rate on preirradiation dose and monomer concentration were found to be 0.2 and 1.1 order, respectively. The overall activation energies for this grafting were calculated to be 15.2 and 4.8 kcal/mol below and above 35°C, respectively. The relationship between the grafting rate and film thickness gave a negative first-order dependence.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1981.070260925
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