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Volume 15, Issue 158
Displaying 1-8 of 8 articles from this issue
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Shigeo Iwayanagi, Heinosuke Nakane, Teruo Hideshima1958 Volume 15 Issue 158 Pages 333-338
Published: June 25, 1958
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSThe Effect of γ-irradiation upon the (bulk) viscosity of several silicone oils is investigated under various conditions and the linear relation between the fluidity and radiation does as determined by Charlesby is found to be substantiated in its main features. A method of radiation dosimetry utilysing the relationship is proposed and discussed briefly. The viscosity as a function of shear rate (Non-Newtonian viscosity) is measured on one specimen irradiated with a radiation dose slightly smaller than that for the incipient gel formation.View full abstractDownload PDF (1123K) -
III. Electrophoretic Study of a Synthetic Polyelectrolyte, Poly (vinyl alcohol) Partially Acetalized with Glyoxylic AcidNorio Ise, Masao Hosono, Ichiro Sakurada1958 Volume 15 Issue 158 Pages 339-347
Published: June 25, 1958
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSElectrophoretic behaviors of poly (vinyl alcohol) partially acetalized with glyoxylic acid were studied. The mobility was found to be almost independent of the degree of polymerisation and to increase with the carboxyl group content. The mobility decreased steadilty with the polymer concentration for samples of low charge density, while it went through a minimum for those of higher charge density. The mobility, moreover, decreased in the sequence of increasing ionic strength under our experimental conditions. Comparing the number of charges of this polyacid in buffer solutions by means of Debye-Henry's theory from the mobility and the value conductometrically determined, it's applicability was confirmed to quantitatively describe the electrophoretic behavior.View full abstractDownload PDF (2687K) -
II. On Gelation of PVA Aqueous SolutionsYasuji Ohyanagi, Masakazu Matsumoto1958 Volume 15 Issue 158 Pages 348-352
Published: June 25, 1958
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSIt is well known that the viscosity of concentrated aqueous solutions (10-20%) of PVA increases with time. Varying polymer concentration, polymerization degree, and polymerization temperature, at which original polyvinyl acetate was synthesized, their effects on the increase of viscosity were studied. The increase of apparent viscosity with time is well represented by ηt=η0 (1+αt), where ηt and η0 are the solution viscosity at time t and 2 and α is a constant. The constant a is proportional to the square of the concentration, independent on polymerization degree, polymerization conversion, and molecular weight distribution of PVA.The apparent “activation energy”of K from it's temperature dependence is-13.5kcal/mol. It is remarkable that K is dependent on the polymerization temperature at which original polyvinyl acetate was polymerized.The higher the polymerization temperature, the smaller is K.View full abstractDownload PDF (905K) -
I. Chain Transfer of Styrene Radical to Poly-2-vinylpyridineSeizo Okamura, Kenji Takeya1958 Volume 15 Issue 158 Pages 353-358
Published: June 25, 1958
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSWhen styrene is polymnerized in presence of poly-2-vinylpyridine having low molecular weight (called α-polymer), the degree of polymerization of polystyrene becomes lower by chain tmansfer reaction. Therefore, the chain transfer constant of poly-2-vinylpyridine (Cp) can be calculated by usual method. The value of this Cp was obtained;Cp=8×10-4-10×10-4 (50°C). It was found that the initiator, benzoylperoxide or 2, 2′-azobisisobutyro nitrile, which was used in the polymerization of 2-vinylpyridine, had no effect on the Cp value, and the Cp was independent of the molecular weight of a-polymer. These facts suggest that the chain transfer to the end group of α-polymer is negligible small. By the method of turbidimetric titration, the existence of 2-vinylpyridine-styrene graft copolymer could be found evidently.View full abstractDownload PDF (1053K) -
III. Solution Polymerization of Vinyl Acetate with Presence of Polyvinyl AlcohoTakuhiko Motoyama, Seizo Okamura1958 Volume 15 Issue 158 Pages 359-363
Published: June 25, 1958
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSSoluble grafted polymer is obtained by the solution polymerization of vinyl acetate in 50% acetic acid aqueous solution with presence of polyvinyl alcohol. Grafting efficiency of polyvinyl alcohol becomes larger as the degree of polymerization increases, and these mechanism are considered.View full abstractDownload PDF (830K) -
IV. Graft-polymerization of Acrylonitrile on to Polyvinyl Acetate and Its Spinning ExperimentsTakao Yamashita, Seizo Okamura1958 Volume 15 Issue 158 Pages 363-367
Published: June 25, 1958
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSAcrylonitrile is polymerized in emulsion or solution with presence of polyvinyl acetate and graft polymers are found to form between two polymers. The grafted polymers are spun into fibers from dimethyl formamide solution. The fiber obtained from grafted polymers is more heat-resistant than that of copolymer or mixture. These results are coincided with that previously reported by Mori and Sakurada (on polyvinylalcohol fibers) and also by Coleman (on polyethylene terephthalate fibers).View full abstractDownload PDF (907K) -
XXIV. The Cationic Copolymerization of Styrene and Acenaphthylene Catalysed by Borontrifluoride-Eatherate (The Copolymerization Reactions and the Properties of the Copolymers)Kazuo Saotome, Minoru Imoto1958 Volume 15 Issue 158 Pages 368-373
Published: June 25, 1958
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSCopolymerization of styrene and acenaphthylene c atalysed by borontrifluoride-eatherate in benzene solution was studied. The rates of copolymerization reactions were much lower than the rates of either of their homopolymerization reactions. The monomer reativity ratios at 30°C were determined;
γ1=0.3±0.1γ2=4.4±0.3
The softeninig point of the copolymer rised with the increase of acenaphthylene in composition. The intrinsic viscosities of the copolymers were much lower than that of polystyrene prepared under the same conditions. The solubility of the copolymers was also investigated.View full abstractDownload PDF (1000K) -
XXV. The Kinetics of the Cationic Copolymerization of Styrene and Acenaphthylene Catalysed by Borontrifluoride-EatherateKazuo Saotome, Minoru Imoto1958 Volume 15 Issue 158 Pages 373-380
Published: June 25, 1958
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSThe kinetics of the cationic copolymerization of styrene and acenaphthylene catalysed by borontrifluoride-eatherate in benzene solution were studied. The rate equations of homopolymerization of styrene and acenaphthylene were expressed as follows;-d [M]/dt=k1 [M] 2 [C](styrene), -d [M]/dt=k2 [M][C](acenaphthylene). Assuming possible reaction mechanisms, the rate equations of the copolymerization reaction were discussed. The lowering of the rate in copolymerization reaction and of intrinsic viscosity of copolymers were able to be explained with the mechanism involved “Cross termination” reactions. The effect of water on the copolymerization reaction was also invertigated.View full abstractDownload PDF (1157K)
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