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Volume 46, Issue 3
Displaying 1-9 of 9 articles from this issue
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Tomoyuki KASEMURA, Toshio HATA1989 Volume 46 Issue 3 Pages 125-130
Published: March 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSInterfacial tensions (γW/S) of solutions of poly (vinyl alkylate) s (PVAI) having various side chain lengths (number of carbon atoms, m) from C2 to C16 were measured in contact with water by the sessile drop method at various temperatures. Three kinds of solvents (chlorobenzene, toluene, and cyclohexane) were chosen so that the solubility parameter (SP) is larger than or smaller than that of all PVAl's, or has on intermediate value. The γW/S of the chlorobenzene and cyclohexane solutions increased with increasing m, while for the toluene solutions it went through a maximum value at m=4 and to the minimum at m=10. These results were analyzed using the following two factors: the polarity of PVAl represented by the ratio of the polar component of surface tension to the total one (xP=γP/γ), and the differences of SP (Δδ=|δS-δP|) between PVAI and solvent, which were calculated by Small's equation. In the case of both xP and Δδ decreasing with m, the γW/S increased monotonously. In the case of xP decreasing and Δδ increasing with m, the Δδ had the dominant effect on γW/S in the region of Δδ<0.5, while in the region of Δδ>0.5, the xP was the dominant factor in the behavior of γW/S. It was found that the γW/S plotted against the parameter P= (xP) × (Δδ) 2 gave a single characteristic curve for each series of solutions.View full abstractDownload PDF (1161K) -
Kazutomi SUZUKI, Kenji NAKATANI, Hiroshi OKANIWA, Shigenohu SOBAJIMA, ...1989 Volume 46 Issue 3 Pages 131-138
Published: March 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSA continuous process to prepare monolithically integrated amorphous silicon solar cells with polyester film substrates has been developed. In this report, the substrate films, pottants and protective covers are described. The substrates are exposed to temperatures above 200°C in the glow-discharged CVD apparatus. As a result, the substrates emit water and oligomers. The poly (ethylene terephthalate) films coated with aluminum and poly (ethylene naphthalate) films did not generate many oligomers even under high temperatures. Small dimensional changes under tensions and high temperatures during the CVD process, and effects of surface roughness were studied. Ethylene vinyl acetate copolymer was utilized as a pottant agent. Various accelerating weathering and degradation tests were performed. Glasses, poly (ethylene terephthalate) films and polycarbonate double-layered sheets were utilized for the protective cover. The highest practical conversion efficiency now available was 6.1% for a cell of 20×60cm size.View full abstractDownload PDF (2638K) -
Koichi TAKADA, Jiro RYUGO1989 Volume 46 Issue 3 Pages 139-144
Published: March 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSPartially hydrolyzed polyacrylamides whose molecular weight is more than ten million were prepared as polymeric flocculants. Samples of different molecular weight distributions were used. Their solution properties were evaluated as a function of molecular weights and distributions. Shear dependence of viscosity, spinnability and molecular chain scission give the useful means for practical characterizations of these high molecular weight samples. Among these, spinnability is the most effective because of the simplicity and the sensitivity to molecular weight distribution. In addition, the flocculation test in a clay suspension was performed as a function of molecular weight and its distribution. In the previous references it was reported that a broader distribution of molecular weight led to better performance of flocculation. But in the case where suspension concentration is high, this was not the case. Thus one has to choose a molecular weight distribution to meet the specific requirements of polymeric flocculants.View full abstractDownload PDF (959K) -
Koichi TAKADA, Jiro RYUGO1989 Volume 46 Issue 3 Pages 145-150
Published: March 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSSolution properties of polymeric flocculants made of partially hydrolyzed polyacrylamide whose molecular weight is more than ten million are evaluated as a function of the charge density (carboxylate content) and its distribution. It is found that neither Brookfield viscosity nor spinnability depend on the charge density distribution, but they do depend significantly on the molecular weight distribution, as reported in study (I). Therefore, these evaluations could not provide any means of practical characterization of charge density distribution, whereas it was useful for the characterization of molecular weight distribution as reported in study (I). Electrophoresis was an useful means for a practical characterization of the charge density distribution. The flocculation characteristics in a clay suspension are evaluated as a function of the charge density and its distribution. It is found that a narrow distribution gives a better performance of flocculation under any conditions of suspension such as concentration and pH of solution.View full abstractDownload PDF (1008K) -
Fumihiko OZAKI, Kiyoshi SAYAMA, Koichi KUROH, Yoshiaki FUJIKURA, Tetsu ...1989 Volume 46 Issue 3 Pages 151-160
Published: March 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSTo produce poly (γ-benzyl L-glutamate) (PBLG) film cast from liquid crystalline solution in an electric field, the changes of the superstructure during the cast process and the orientation behavior of the film were observed by means of polarized microscopy and small-angle light scattering techniques. At the beginning of cast process in an electric field, the polydomain structure in the liquid crystalline solution forms rodlike domains, flowing parallel to the field direction (FD); the major axes of the rodlike domains preferentially orient to the same FD. The molecular axes of PBLG in the rodlike domains are parallel to the FD. As the evaporation of solvent progresses, the center positions of the neighboring molecules are arranged in order by intermolecular interaction. Continuing this orderly process, the planes formed by their centers arrange perpendicular to the FD; these planes then form the layered structure with their surfaces perpendicular to the FD. As the result of an increase in viscosity by evaporation of the solvent, the flow of the solution comes to a halt. In this process, the molecular axes are parallel to the FD. This layered structure does not change until evaporation is accomplished; it can be referred to as a“band structure”. A cast process model of PBLG liquid crystalline solution in an electric field is proposed.View full abstractDownload PDF (3074K) -
Kaoru KAWASE, Hiroshi SAKAMI, Kiyoshi HAYAKAWA1989 Volume 46 Issue 3 Pages 161-168
Published: March 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSComplex coacervation introduced by gamma-ray induced polymerization of acrylamide in colloidal silica was studied. The complex coacervate was formed by polymerization of acrylamide dissolved in a colloidal silica and methanol mixture. Complex coacervation (two-phase separation of the mixture) was observed only when the concentration of methanol was between 33 and 41 percent by volume, and the concentration of colloidal silica did not affect it. Although two phase separation was not influenced by pH change, the content of polyacrylamide was bigger in the equilibrated solution in acidic regions. It was, however, bigger in the complex coacervate at neutral and in alkaline regions. The content of polyacrylamide was also calculated from the partticle diameter of complex coacervate measured by small angle X-ray scattering, and the result was well coincided with the analytical result. The stability of the complex coacervate against the addition of salts was better than that of the untreated colloidal silica. The rate of electrophoretic transport of the complex coacervate was also lower than that of the colloidal silica. From these observation it was concluded that the hydrophobic colloidal silica particles were protected by the surrounding hydrophilic polyacrylamide.View full abstractDownload PDF (1470K) -
Takao SASHIDA, Kenji MOTOSUGI, Kanako AKABA1989 Volume 46 Issue 3 Pages 169-176
Published: March 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSIn order to develop a capacitive type humidity sensor with high accuracy (±1% relative humidity), some characteristics as humidity-sensitive materials were investigated for many polymers with carbonyl groups or hydroxyl groups. Three kinds of polymers were picked up as suitably humidity-sensitive materials, with hysteresis less than 1.5% RH: poly (vinyl acetate), poly (methacrylic ester) s, and cellulose acetate butyrate. The changes of dielectric constants of polymers were caused by absorption and desorption of water to the hydrophilic groups in polymers. Moreover, the absorption of water was under the influence of both the kind of the hydrophilic group and the hydrophobic group around hydrophilic group.View full abstractDownload PDF (1484K) -
Takeshi YAMAMOTO, Kiyohisa TAKAHASHI, Yuhji KON, Kazunori KOBAYASHI1989 Volume 46 Issue 3 Pages 177-181
Published: March 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSTwo types of epoxy prepolymers: bisphenol A (EPIKOTE 828) and phenol novolak (EPIKOTE 154), were cured with 2 kinds of phosphazene derivatives: diamino-tetraphenoxy-cyclotriphosphazene (PC 10) and trichloro-tridimethylamino-cyclotriphosphazene (Cl 3). The temperature dependence of the tensile behavior and the heat resistance of the cured epoxy resins were investigated by uniaxial tensile testing and thermogravimetric analysis (TGA). The epoxy resin cured with Cl 3 showed higher Young's modulus values in the temperature range up to 100°C for EPIKOTE 828 and up to 130°C for EPIKOTE 154, compared with the epoxy resins cured with PC 10 and m-phenylenediamine. At 150°C, EPIKOTE 154 cured with Cl 3 showed the Young's modulus and breaking strength comparable to, and the elongation higher than, the values of that cured with m-phenylenediamine. The epoxy resins cured with PC 10 and Cl 3 showed higher weight remaining above 500°C in TGA. And the thermal decomposition became complete at around 800°C, which was about 200°C higher than for the epoxy resin cured with m-phenylenediamine.View full abstractDownload PDF (856K) -
Kiyoshi NARUCHI, Fumihiko AKUTSU, Tsutomu AYUHA, Masatoshi MIURA1989 Volume 46 Issue 3 Pages 183-188
Published: March 25, 1989
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESS1-Hexene-3, 4-dicarboxylic anhydride (1a), (E) -2-hexene-3, 4-dicarboxylic anhydride (2a), dimethyl 1-hexene-3, 4-dicarboxylate (1e) and dimethyl (E) -2-hexene-3, 4-dicarboxylate (2e) do not radically homopolymerize. Radical copolymerization of these monomers (M2) with acrylonitrile (AN, M1) was conducted at 60°C with AIBN, and the following monomer reactivity ratios were obtained:
AN-1a r1=5.02, r2=0.00
AN-2a r1=15.98, r2=0.00
AN-1e r1=8.46, r2=0.00
AN-2e r1=17.40, r2=0.00
At the same M1/M2 feed ratio, the terminal-olefinic monomers (1a and 1e), whether acid anhydride or ester, led to higher contents in the copolymers than the inner-olefinic counterparts (2a and 2e, respectively). The viscometric molecular weights of the copolymers decreased significantly with a decrease in acrylonitrile content in the monomer feed. For the AN-2a and AN-2e copolymers, the two types of methyl groups, one attached to the main chain and the other to the side chain, were discriminated by 1H NMR spectroscopy. 1H NMR analysis of the AN-1a and AN-1e copolymers thus showed that they did not contain repeat units derived from 2a and 2e which would be formed by migration of the double bond of 1a and 1e, respectively.View full abstractDownload PDF (824K)
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