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Volume 35, Issue 11
Displaying 1-11 of 11 articles from this issue
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Shoji ICHIHARA, Yuzuru KONO, Masayuki EGAMI, Setsuya FUKUI1978 Volume 35 Issue 11 Pages 677-684
Published: November 25, 1978
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSAnti-static electricity (AS) of biaxially oriented polypropylene film was studied from points of view of (1) the relation between the amount of AS agent on the film surface and AS effect, and (2) the relation between the diffusion rate of AS agent onto film surface and AS effect. In the early stage of migration, it seems that AS agent on the film is present as isolated “island”. Then the islands are connected together and AS agent forms monolayer on the film. After the monolayer of AS agent was formed, AS effect of film becomes nearly constant. AS effect vs. log (aging period) curves at different temperature can be superimposed along log (aging period). On the assumptions that the electric conductivity of a film surface is proportional to the amount of AS agent migrated onto the film surface and that the rate of migration of AS agent is expressed by a diffusion equation, a relation between AS effect and aging period is derived. The resulting equation explains the experimental results with enough accuracy for practical uses.View full abstractDownload PDF (1236K) -
Shizunobu HASHIMOTO, Isao FURUKAWA, Hideaki YAMAMOTO1978 Volume 35 Issue 11 Pages 685-692
Published: November 25, 1978
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe synthesis of poly (p-xylylidene) from p-xylylene dichloride by solution method using potassium t-butoxide in DMSO, and by phase-transfer catalyst method using tetra-n-butylammonium chloride was investigated. The latter method gave the polymer in a good yield, which contained a small amount of ether linkage in the main chain. This polymer showed a poorer thermal stability than the polymer obtained by solution method. Poly (p-xylylidene) derivatives containing chlorine or nitro group in the aromatic ring and sulfonyl or carbonyl group in the main chain were also prepared from the corresponding substituted p-xylylene dichloride by solution method. All the polymers except one containing nitro group started decomposing at ca. 340°C. Thus the substituted groups in the polymer scarcely affected the thermal stability of the polymers.View full abstractDownload PDF (1241K) -
Yoshiaki TANAKA1978 Volume 35 Issue 11 Pages 693-698
Published: November 25, 1978
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSAn isocyanurate having N- [ω-hydroxypoly (tetramethylene oxide)] groups was prepared in high yield by the reaction of a-chloro-ω-hydroxypoly (tetramethylene oxide) with sodium cyanate in N, N-dimethyl-formamide. The structure of this product was determined by elemental analysis, and IR and NMR spectra. This triol isocyanurate was more viscous than the glycerine-based poly (oxypropylene) triol having the same molecular weight. A polyurethane rigid foam was prepared by the polyaddition of the polyethertriol isocyanurate with crude 4, 4′-diphenylmethane diisocyanate. The foam has a favorable friability and high heat and flame resistant properties.View full abstractDownload PDF (1008K) -
Yasuo MURATA, Masao SUMITA, Keizo MIYASAKA, Kinzo ISHIKAWA1978 Volume 35 Issue 11 Pages 699-703
Published: November 25, 1978
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe effect of aqueous solutions of sulfuric acid, the sole known solvent for Kevler [poly (p-phenylene terephthalamide)] fiber, on the mechanical properties of the fiber placed in the solution, was investigated. The tensile strength and breaking elongation of Kevler decreased with increasing concentration of sulfuric acid, whereas the Young's modulus, determined at 1% strain of this fiber, remained nearly constant in the range of sulfuric acid concentration from 0 to 60 vol % in water. Above this concentration the modulus decreased rapidly due to the dissolution of the fiber. Sulfuric acid gave no effect on the stress relaxation of the fiber in the concentration range of 0 to 50 vol In solutions of sulfuric acid concentration above 70 vol %, the relaxation moduli decreased owing to the dissolution of the fiber, while any remarkable change in stress relaxation was not observed when the fiber was allowed to stand in the solution for a long time. These results suggest that the effect of aqueous sulfuric acid solutions on the mechanical properties of Kevler fibers is different from a plasticizer effect which is well known for usual polymer-solvent systems and seems to be caused by the solvent cracking.View full abstractDownload PDF (800K) -
Rate Constants of Elementary Reactions in Radical Polymerization of 2, 6-Dimethylphenyl MethacrylateTakayuki OTSU, Bunichiro YAMADA, Shigeru SUGIYAMA1978 Volume 35 Issue 11 Pages 705-711
Published: November 25, 1978
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSAbsolute rate constants of propagation and termination in radical polymerization of 2, 6-dimethyl-phenyl methacrylate were determined by means of a rotating sector method as 6.8×101 and 2.10×106lmol-1 sec-1, respectively, in bulk at 30°C. The propagation rate was decreased by introducing o-methyl groups on the benzene ring. Absolute rate constants of cross propagations were calculated from the absolute propagation rate constant and the monomer reactivity ratios of copolymerizations, to estimate the reactivities of the monomer and the polymer radical. The methyl groups at 2- and 6-positions were found to decrease the reactivities of both the monomer and the polymer radical by comparing of the calculated rate constants with those for phenyl methacrylate and its polymer radical. The decrease in the reactivities seems to be accounted for by a steric effect of the methyl groups which are conformationally close to the carbon-carbon double bond or the radical center.View full abstractDownload PDF (1118K) -
Preparation of Polyamide-imides from Phosphorus-Containing Bisamide-Anhydrides and Aromatic DiaminesMasaru SEITA, Moriyuki SATO, Masaaki YOKOYAMA1978 Volume 35 Issue 11 Pages 713-719
Published: November 25, 1978
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSPhosphorus-containing polyamide-imides were synthesized by the bulk polycondensation of 4, 4′- [3, 3′- (alkylphosphoryldiphenylene) -bis (iminocarbony1)] diphthalic anhydride (APBPA) with aromatic diamines at high temperatures, and the reaction conditions were investigated. The polymers were insoluble in organic solvents such as DMF, DMA and DMSO. When diamines containing hetero atom (S or P) were used, the polymers were soluble in conc. H2SO4. Reduced viscosities of polymers measured in conc. H2SO4 solution at 30°C were 0.24-0.26 g-1dl. Thermal analyses showed that the polymers degraded at 400-500°C in air or in nitrogen and that apparent activation energies for thermal decomposition under nitrogen atmosphere were 40-62 kcal/mol. The polymers were self-extinguished immediately after the flame was removed.View full abstractDownload PDF (1079K) -
Yasuji OHTSUKA, Takao SENGA1978 Volume 35 Issue 11 Pages 721-727
Published: November 25, 1978
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSLight-focusing plastic rods (LFRs) with quadratic gradient of refractive index were prepared by the two-step copolymerization of a diallyl ester and methyl methacrylate (MMA). Diallyl isophthalate (DAI) -MMA monomer pair was found to yield LFRs with wider acceptance angle (2θ) and larger ΔW (weight increment in the immersion process) than those prepared from diallyl phthalate-MMA monomer pair. The above results are explained in terms of the difference in unsaturation of diallyl ester units in prepolymer gel rods (GRs). The relations between index-distribution constant A and ΔW of DAI-MMA LFR and the preparation conditions (composition of DAI GR, initiator concentration, immersion temperature, immersion time and heat treatment) were elucidated in terms of diffusibility of MMA monomer in GR and fixation of MMA unit by copolymerization with allylic group of DAI polymer. The radial distribution of refractive index estimated from the distribution of copolymer composition for a representative DAI-MMA LFR gave distribution-constant A which is in good agreement with the value calculated from lens function of the LFR.View full abstractDownload PDF (1074K) -
Hiroshi UENO, Shinya OTSUKA, Kazuo TAIRA, Akira KISHIMOTO1978 Volume 35 Issue 11 Pages 729-733
Published: November 25, 1978
Released on J-STAGE: March 25, 2010
JOURNAL FREE ACCESSTemperature and molecular weight dependences of bulk diffusion coefficient (DB) and local diffusion coefficient (DL) of Nylon 12 in melt have been studied. For Mn=9, 200-29, 000, DB and the apparent activation energy (EDB) were 10-10-10-18 cm2/sec and 71.1-114 kJ/mol at 185-250°C, respectively. DL and the apparent activation energy (EDL) were 10-5-10-6 cm-2/sec and 22.2-23.0 kJ/mol, respectively. Log DB was a linear function of log MW, while log DL, stayed almost constant.View full abstractDownload PDF (835K) -
Yasuji OHTSUKA, Masao CHINO1978 Volume 35 Issue 11 Pages 735-741
Published: November 25, 1978
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSPhotocopolymerizations of 2, 2, 2-trifluoroethyl methacrylate (M1) with vinyl o-chlorobenzoate (M2) were carried out in the presence of benzoin (B) to yield light-focusing plastic rods with parabolic gradient of refractive index in the region near center axis (radius Rc). The gradient-constant A was measured by reduction rate of image (γ). A method to estimate Rc from γ and view field of the rod lens was proposed. Both A and Rc decreased with an increase in monomer feed ratio M1/M2 ranging from 3.0 to 5.0. An increase in the concentration of B from 0.025 to 0.100 wt% caused an increase in A accompanied by a reduction in Rc. Elevation of photocopolymerization temperature from 20 to 40°C caused decreases in both A and Rc. The above results are explained qualitatively in terms of the computer simulated index-distribution profiles. It is concluded that the photopolymerization at low temperature yields the LFR with excellent optical properties.View full abstractDownload PDF (1100K) -
Kiyokazu IMAI, Masakazu MATSUMOTO1978 Volume 35 Issue 11 Pages 743-746
Published: November 25, 1978
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSPoly (vinyl alcohol) s derived from the product of polymerization of vinyl propionate and vinyl butyrate in bulk at 60°C have been characterized by measuring their clouding time in aqueous dimethyl sulfoxide solution and swelling degree in water, and by carrying out the coloration reaction with iodine. The polymer properties varied with their starting monomer structure. It was thus estimated that the structural regularity of poly (vinyl alcohol) was obtained in the order of vinyl butyrate>vinyl propionate>>vinyl acetate.View full abstractDownload PDF (607K) -
Kiyokazu IMAI, Unpei MAEDA, Masakazu MATSUMOTO1978 Volume 35 Issue 11 Pages 747-750
Published: November 25, 1978
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSConcentrated aqueous solutions of poly (vinyl alcohol) were derived from the polymerization of vinyl acetate at 60°C in solutions of ethylene carbonate, acetonitrile, acetic anhydride, acetone, methanol, and 40-% aqueous methanol. Their viscosity stability was found to depend markedly on the nature of polymerization medium used.View full abstractDownload PDF (577K)
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