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Volume 14, Issue 148
Displaying 1-7 of 7 articles from this issue
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Takaharu Nagano, Makoto Oguma1957 Volume 14 Issue 148 Pages 397-401
Published: August 25, 1957
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSThe reliable determination the coefficient of kinetic energy correction (viscometer coefficient) of capillary viscometer is difficult according to the calculation method which has hither to been used. From the results of measurements of effiux time of water at various temperatures (at the intervals of 5°C in the range from 5 to 80°C) not only the viscometer const. and viscometer coefficient could be determined precisely but also they were found to change with effiux time. The results shows the necessity of taking many experimental points, as in the present method, in order to get a precies coefficientView full abstractDownload PDF (893K) -
Ryozo Inoue, Seiichi Mima1957 Volume 14 Issue 148 Pages 402-411
Published: August 25, 1957
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSIn the polymerization of styrene catalyzed by acid, it is considered that styrene forms a conjugated acid, i. e., a carbonium ion, and reacts with it, growing to a polymer. In this paper, electronic spectra of styrene and some related compounds dissolved in sulfuric acid are shown. Carbonium ions give the absorption spectra which are quite different from those of original organic bases, and this shows that electronic states of the formers are clearly different from those of the tatters.Moreover, the carbonium ion of styrene monomer shows a different absorption spectrum from that of the ion of styrene dimer, owing to the hyper-conjugation effect of methyl radical in the former. Finally, energy level of carbonium ion is calculated by free electron model, and the result is compared with the experimental values, and discussion with regard to the acid catalyzed polymerization reaction of styrene is done.View full abstractDownload PDF (1370K) -
III. Swelling Equilibria of Polyvinyl Acetate in Binary Mixtures Containing Water as One ComponentAkio Nakajima, Kazuo Miyamichi, Ichiro Sakurada1957 Volume 14 Issue 148 Pages 412-418
Published: August 25, 1957
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSSwelling of crosslinked polyvinylacetate in binary mixtures of polar solvents, containing water as one component, was studied and the composition of liquids in the two phases (the polymer free liquid phase and the swollen polymer phase) measured.Thermodynamic relations in these ternary systems were discussed using the relations obtained in the binary systems.View full abstractDownload PDF (1093K) -
I. On Huggins' k′-value of PVAc Solution in Benzene and AcetoneKiyokazu Imai, Umpei Maeda, Masakazu Matsumoto1957 Volume 14 Issue 148 Pages 419-424
Published: August 25, 1957
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSThe viscosities of dilute solutions of the polyvinyl acetate, obtained by various polymerization conditions were measured in benzene and acetone and their concentration dependencies were compared.The Huggins' k′ value of the common polyvinyl acetate, obtained by solution and bulk polymerization, is nearly constant (0.35-0.40) and independent of the existence of branching. However, the k′ value of the product, obtained by special emulsion polymerization yielding many branches, is much higher than that of the former.View full abstractDownload PDF (1010K) -
II. The Concentration Coefficient of Viscosity Number of PVAc Solution in Methanol and Toluene[in Japanese], [in Japanese]1957 Volume 14 Issue 148 Pages 425-429
Published: August 25, 1957
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSThe viscosities of dilute solutions of polyvinyl acetate in methanol and toluene were measured. A relation of a2∝[η] n was obtained, where [η] is limiting viscosity number and a2 is the concentration coefficient of viscosity number; n is nearly 2 in methanol and 2.17 in toluene. It is generally observed that n is always 2 in good solvent system and the case of n<2 is restricted to poor solvent system.View full abstractDownload PDF (686K) -
Noboru Yamazaki, Shu Kambara1957 Volume 14 Issue 148 Pages 430-434
Published: August 25, 1957
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSThe reaction of etherdinitriles with formaldehyde in strong sulfuric acid solution at room temperature has been studied in detail. Etherdinitriles were prepared by cyanoethylation of glycols. Optimum concentration of sulfuric acid was about 95% and over fifteen times mol ratio of sulfuric acid and dinitriles was needed to accomplish the polymerisation smoothly. Polyetheramides produced have a melting point (decomp.) above 200°C and their intrinsic viscocities in formic acid solution were 0.08-0.48. Solvents for the polymer were similar to those for 66 nylon.View full abstractDownload PDF (866K) -
Tsutomu Akita, Shin Oishi1957 Volume 14 Issue 148 Pages 435-441
Published: August 25, 1957
Released on J-STAGE: October 14, 2010
JOURNAL FREE ACCESSOn the polymerizing reaction of unsaturated polyester in the presence of peroxide catalyst, a small amount of mercaptan has a marked promoting effect, but its excess has rather retarding effect. This phenomenon can be understood as parallel radical reactions; a redox system reaction between peroxide and mercaptan on one side, and a chain transfer reaction between a propagating radical and mercaptan molecule on the other. By this theory, the authors attempted to explain nit only the gelation phenomena of liquid resin, but also the Rockwell hardness curve of the cured cast resin at high temperature.View full abstractDownload PDF (1249K)
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