Sen'i Gakkaishi
Online ISSN : 1884-2259
Print ISSN : 0037-9875
Volume 44, Issue 11
Displaying 1-19 of 19 articles from this issue
  • Minekazu Kodama, Kazuo Kuramoto
    1988 Volume 44 Issue 11 Pages 529-534
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    For the purpose of studying the effect of stereoregularity of poly (methyl methacrylate) (PMMA) on the interaction and boundary phase structure between PMMA and polyamide substrate, the mechanical dispersion and X-ray photoelectron spectrum (XPS spectrum) were measured for PMMA composite reinforced with short Kevlar® fiber and PMMA film formed on nylon-6 plate, respectively. The interaction between the matrix and reinforcement is estimated to be weaker for the composite made with isotactic PMMA compared with the composites made with atactic and syndiotactic PMMA from the mechanical dispersion data. By analysing the XPS spectra, it can be shown that the enrichment of the carboxylic group at the vicinity of nylon-6 surface occurs for the cases of atactic and syndiotactic PMMA but cannot be seen for the case of isotactic PMMA. This means that the boundary phase structure varies depending on the stereoregularity of PMMA. These differences of the interaction and boundary phase structure can possibly be attributed to the difference of such a molecular characteristic of PMMA as the overall molecular conformation or the degree of constraint on the rotation of molecular chain depending on the tacticity of PMMA.
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  • Tetsuo Asakura, Makoto Demura
    1988 Volume 44 Issue 11 Pages 535-540
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    The physical state and orientation of the water trapped in porous Bombyx mori silk fibroin membranes were examined in the absence and presence of alkali metal salts, NaCl, KCl and LiCI by means of NMR spectroscopy. In spite of the high content of water (93%) in the membrane, doublet 1H NMR peaks of the water molecules were observed and its separation depended strongly on the angle, θ, between the membrane surface and the magnetic field. This trend was independent of the presence of alkali metal ions in the water. From the relationship between the separation of the doublet and the angle, θ, the orientation of the proton-proton axis of the water molecule was found, on the average, parallel to the surface of the membrane. 1H NMR peaks of the water and also, 23Na NMR peaks of the NaCl aqueous solution trapped in the membrane shifted to lower field with increasing angle, θ, indicating the anisotropy of the silk fibroin membrane itself. The diamagnetic susceptibility of the membrane was calculated to be -0.64ppm.
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  • Nobuyuki Tanaka
    1988 Volume 44 Issue 11 Pages 541-545
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    For RIS models of ethylene/propylene and propylene/ethylene random copolymers, the composition dependence of Tm, a and hx was investigated. Where Tm is the melting temperature of copolymer, a is the coefficient in equation (1) and hx is the transition enthalpy per molar structural unit due to quasi-crystal in the amorphous region. The value of a changed with increasing minor component units, differing from the experimental results for nylon-6, 66 and polyethylene-terephthalate copolymers. Whereas hx under the assumption of equation (2) was 454 cal/mol (extrapolated value at 1-XA=0) for ethylene/propylene copolymer and the reasonable value was not obtained for propylene/ethylene copolymer. For latter copolymer, it was presumed that in the range of 1-XA≤0.20 the quasi-crystal is not contained in the amorphous region. XA is the mole fraction of major component units.
    In the next stage, the derivation method of hx from the solubility parameter δp of homopolymers was discussed and for polyethylene-terephthalate and nylon-66, the good agreement between hxs from δp, and equation (1) was obtained. In this case, the transition temperature of the quasi-crystal in the amorphous region should be near the melting temperature of crystal.
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  • Shigeru Tasaka, Norihiro Inagaki, Seizo Miyata, Touru Chiba
    1988 Volume 44 Issue 11 Pages 546-550
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    Dielectric and piezoelectric constants of pullulan, dextran and amylose which were cyanoethylated were measured as functions of temperature and draw ratio. The cyanoethylated polysaccharides having amorphous structure showed two relaxation processes; glass transition at around 120°C and side chain dispersion due to cyanothyl group at -90°C. The dielectric constant, which depended on the molecular orientation of films, was more than 20 for the highly oriented films. Small intrinsic piezoelectric effect, e14, was observed in the drawn film. This may be attributed to the strain of amorphous chain backbone. The sample poled near glass transition temperature revealed a piezoelectric effect e31 on the basis of a C-CN dipole orientation.
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  • Masakazu Yoshikawa, Tomoki Ohsawa, Masataka Tanigaki, Wataru Eguchi, N ...
    1988 Volume 44 Issue 11 Pages 551-557
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    Separation of ethanol from aqueous ethanol solution was carried out by pervaporation through a membrane which consists of common synthetic polymers. A membrane from poly (cyclohexyl methacrylate-co-styrene) showed membrane performance that preferentially permeated ethanol from ethanol-water mixtures by pervaporation technique. The pervaporation of ethanol-water mixture through the present membrane was analyzed as a solution-diffusion process.
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  • Kenichiro Arai
    1988 Volume 44 Issue 11 Pages 558-562
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
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    Polystyrene-grafted cross-linked polystyrene beads were prepared with a two-step polymerization, consisting of the first step; suspension polymerization of styrene containing small amount of divinyl benzene using tetraethylthiuram disulfide as an initiator, and the second step; polymerization of styrene onto the cross-linked polystyrene beads. Both percent grafting and grafting efficiency by this method were higher than those by conventional graft polymerization onto the beads using benzoyl peroxide as an initiator. In sulfonation by 1, 4-dioxane-sulfur trioxide adduct, the higher the percent grafting, the fewer sulfonic acid groups were introduced into the beads. Catalytic activity of the sulfonated beads on the hydrolysis of dextrin, however, increased with the increasing percent grafting, especially at the percent graftings higher than 200%. The catalyses followed ordinary second-order kinetics. The results showed that the increase in the catalytic activity with the increasing percent grafting was due to the effect of grafted chain as a spacer to separate the sulfonic acid group from the insoluble matrix.
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  • Shigeo Hirose, Kunio Nakarnura, Tatsuko Hatakeyama, Hyoe Hatakeyama
    1988 Volume 44 Issue 11 Pages 563-568
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    An aromatic polysulfide was synthesized by the reaction of bis(4-fluorophenyl)phenylphosphine oxide (BFPO) with potassium salt of biphenyl-4, 4′-dithiol (BPDT) in the presence of 18-crown-6. In order to establish the characteristics of polymerization, reaction conditions such as the temperature and the time were changed. The polymerization in N-methyl-2-pyrrolidone (NMP) at 155°C gave the polysulfide having inherent viscosity of 0.71 dl/g(_??_w=6.8×104). An X-ray diffractogram of the polysulfide indicated a typical halo pattern, suggesting that it was amorphous. The thermal properties of the polysulfide were studied by differential scanning calorimetry (DSC) and thermogravimetry (TG). The glass transition was observed in DSC at 232°C. TG measurements showed the onset of thermal decomposition in nitrogen at 480°C, and its activation energy was 158kJ/mol.
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  • THE EFFECT OF THE MODIFICATION OF CELL MEMBRANE COMPLEX
    Kyohei Joko, Joichi Koga
    1988 Volume 44 Issue 11 Pages 569-573
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    The dyeing rate of stretched wool fibers pretreated with polar organic solvents which modify the cell membrane complex (CMC) was investigated in order to elucidate the structural effect in the individual histological components of the intact wool fibers on the dyeing rate of the stretched wool fibers.
    By comparing the relationships between the relative dye uptake (Ct/C) and the square root of the dyeing time (t1/2) for the different stretched wool fibers, considerable differences were found in the initial dyeing behavior between the stretched wool fibers pretreated with the different solvents. On the other hand, there was little difference in the slope of the linear line. These changes of initial dyeing behavior by stretching were attributed not only to the changes into the rough and porous nature of the surface layer, but also to the difference in the modified structure of CMC in the cuticle layer caused by the solvent treatment. The rate of dye penetration within the bulk phase of fibers was nearly the same for all of the stretched wools. A suggestion was made that the structural modification of the cortical-cortical CMC by the solvent treatment was offset by some structural modification in the cortical cells caused by stretching.
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  • Yuhji Kon, Jiro Shimizu, Yugo Morita, Kazuhisa Harakawa
    1988 Volume 44 Issue 11 Pages 574-586
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    The effect, on the spinning tension and false twist torque, of a rotary navel rotating in the same direction as that of the rotor was investigated. Differential equations were derived from the equilibrium of forces acting on the yarn element as it passes over the navel. Then, they were solved numerically based on some considerations on the geometrical position of the yarn. It was found that the navel rotation changes the spinning tension and the false twist torque; and that the angle of yarn direction at the edge of the navel affects their changes as well as the friction coefficient between the navel and the yarn. The results of numerical analysis were supported by experimental evidence. The use of the rotary navel to diminish the exceeding peripheral twist extent (PTE) improved the tenacity, the elongation and the initial modulus of the spun yarn. A navel on which curved-grooves were cut was used by way of trial to change the yarn direction at the edge of the navel. In result, actual reduction in yarn tension was not only observed, as was expected through the numerical analysis, but also brought about a spinning tension lower than the possible least one that had been so far supposed to be attained when friction is absent.
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  • Minekazu Kodama, Kazuo Kuramoto
    1988 Volume 44 Issue 11 Pages 587-590
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
    JOURNAL FREE ACCESS
    Study of X-ray photoelectron spectroscopy (XPS) has been made on the film of poly (hydroxypropyl ether of bisphenol A) (P)/Poly (methyl methacrylate) (M) blend formed on nylon-6 substrate to elucidate the boundary phase structure between the substrate and the polymer blend. It can be found by analysing the C1s spectrum that the boundary phase is almost composed of M alone. This result can be useful for fundamental information to understand the reinforcing mechanism of the Kevla ®-fiber reinforced composite made with P/M blend as matrix.
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  • Fusae Nakanishi
    1988 Volume 44 Issue 11 Pages 591-594
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
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    A new type of multilayer films was prepared using long-chain alkyl diesters of 5, 5′-(1, 4-phenylene)-bis (2-cyano-2, 4-pentadienoic acid). These compounds formed stable monolayers on the water surface when mixed with arachidic acid. The mixed multilayer films with Y-type deposition were obtained successfully. They are photosensitive towards visible light and yielded oligomers or polymers on irradiation.
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  • SUGIO OTANI
    1988 Volume 44 Issue 11 Pages P408-P412
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
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  • YOSHIO SUZUKI
    1988 Volume 44 Issue 11 Pages P413-P418
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
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  • NOBUATSU WATANABE, TSUYOSHI NADAJIMA
    1988 Volume 44 Issue 11 Pages P419-P424
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
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  • HARUO ITO
    1988 Volume 44 Issue 11 Pages P425-P429
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
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  • TAKAMASA KAWAKUBO
    1988 Volume 44 Issue 11 Pages P430-P436
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
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  • MICHIO INAGAKI
    1988 Volume 44 Issue 11 Pages P437-P439
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
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  • YASUHIRO TANABE, EIICHI YASUDA
    1988 Volume 44 Issue 11 Pages P440-P443
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
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  • SHINOBU YAMAOKA
    1988 Volume 44 Issue 11 Pages P444-P447
    Published: November 10, 1988
    Released on J-STAGE: November 28, 2008
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