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Volume 53, Issue 9
Displaying 1-7 of 7 articles from this issue
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Wataru MIZUNO, Machiko KAWAGUCHI, Nobuko SARUKURA, Izumi OMODAKA, Shig ...1996 Volume 53 Issue 9 Pages 513-521
Published: September 25, 1996
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSDegradation properties of injection molded biodegradable polymers were investigated by biodegradability tests in soil and aqueous environments in Toyama prefecture. Biopol was cracked by degradation. The strength was rapidly decreased by cracks in samples. Mater-Bi was degraded from the surface, and the resin and plasticizer were dissolved during the test. The strength and the weight of samples were decreased during the tests. Ecostarplus was not degraded except for the grains of starch on the surface. The strength and the weight loss changed according to the places and depths of the soil where the test samples were buried. The decreases in the strength and the weight during spring and fall were faster than the decreases during winter and spring. It seems that the degradation was effected by degradation bacilli and climate.View full abstractDownload PDF (8187K) -
Akira SUZUKI, Atsushi KAMEYAMA, Tadatomi NISHIKUBO1996 Volume 53 Issue 9 Pages 522-529
Published: September 25, 1996
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe syntheses of soluble polyesters with pendant hydroxy groups were studied. The polyaddition of bisphenol A diglycidyl ether (BPGE) with adipic acid (AA) using tetrabutylammonium bromide (TBAB) as a catalyst at 60°C for 24 h provided a soluble polymer with number-average molecular weight (Mn) =9800 in 79% yield. Certain soluble polyesters were prepared in good yields by the polyaddition of various bisepoxides with dicarboxylic acids under the similar controlled reaction conditions. The reaction of the resulting polymer with diazonaphthoquinone sulfonyl chloride (DNQ), which is a typical photo-decomposable compound, proceeded in 85% degree of esterification to give the corresponding photo-reactive polymer P-2a. Photochemical reaction of P-2a film occurred smoothly by the irradiation with UV-light. The photo-irradiated polymer film became soluble in 3% alkali aqueous solution.View full abstractDownload PDF (1420K) -
Akinori TSUBATA, Atsushi KAMEYAMA, Tadatomi NISHIKUBO1996 Volume 53 Issue 9 Pages 530-536
Published: September 25, 1996
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe syntheses of polyesters containing norbornadiene (NBD) residues in the main chain were studied. The ring-opening copolymerization of 2, 5-NBD-2, 3-dicarboxylic acid anhydride (NBDA) with phenyl glycidyl ether using stannous chloride as a catalyst at room temperature for 3 days in toluene gave a polyester containing NBD residues in the main chain in high yield. The number average molecular weight of the resulting polyester was nearly 3500. The ring-opening copolymerization of NBDA with various epoxy compounds under the same conditions proceeded to give the corresponding NBD polyesters. The photochemical valence isomerization of NBD polymers in the film state proceeded quantitatively to produce the corresponding quadricyclane (QC) polymers upon irradiation with a xenon lamp for 7 h. However, it was also found that these polymers were effectively sensitized by the addition of 4, 4′-bis (diethylamino) benzophenone or 4- (dimethylamino) benzophenone. The photo-irradiated polymers containing QC moieties released about 70-79 kJ/mol of thermal energy.View full abstractDownload PDF (1238K) -
Naoki HASEGAWA, Arimitsu USUKI, Akane OKADA1996 Volume 53 Issue 9 Pages 537-541
Published: September 25, 1996
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSStar-shaped nylon 6 s, whose polymer arms radiated from the initiator, were prepared, and its thermal properties were studied. The melting point and the heat of fusion decreased, as the number of the polymer arms increased. The decrease of melting point was caused by the diminution of the molecular weight of polymer arms. The decrease of heat of fusion was due to the presence of the initiator in polymer chains, indicating that the nylon 6 units near the initiator could not crystallize. The glass transition temperature increased, as the number of the polymer arms increased. The initiators of star-shaped nylon 6 played a role as the cross-linking points. Consequently, the thermal properties of the star-shaped nylon 6 were dependent on the number of the polymer arms, the molecular weight of polymer arms, and the size of the initiator.View full abstractDownload PDF (818K) -
Koji KANO, Hiroshi TAKASHIMA, Yasuko TANIUCHI1996 Volume 53 Issue 9 Pages 542-547
Published: September 25, 1996
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe poly (vinyl chloride) (PVC) thin films embedding amphiphilic cyclodextrins at the one sides of the films have been prepared by spreading the solutions of the mixtures of PVC and cyclodextrin derivatives in THF-toluene on water. The XPS analyses indicate that the hydrophilic cyclodextrin head groups are arranged at the surfaces of the polymer films. The chiral recognition of such cyclodextrin films has been studied by dipping the films in the aqueous solutions of (R) - and (S) -1, 1′-binaphthy1-2, 2′-diylphosphates (BNP) and analyzing the films by means of XPS spectroscopy. The (S) -BNP is preferentially bound to the cyclodextrin-embedding PVC films, which is in agreement with the results obtained for the homogeneous aqueous system as well as those for the cyclodextrin monolayer and LB membranes. The enantiomer selectivity of the film is altered by the dipping time. The XPS and FT-IR measurements indicate that the 2-naphthoate anion in water is bound to the cyclodextrin film in its salt form. Deducing from this result, the BNP anion in water seems to be transferred to the cyclodextrin film in its salt form. It is assumed that the chiral recognition is achieved by the enantioselective inclusion of BNP into the cyclodextrin cavity at the surface of the PVC film.View full abstractDownload PDF (2360K) -
Hiromasa ADACHI, Teruo HASEGAWA1996 Volume 53 Issue 9 Pages 548-554
Published: September 25, 1996
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSThe distribution in the diameter of the cross sections of cells in some flexible polyurethane foams was cleared. In addition the distribution in the diameters of the three-dimensional cells was estimated on the basis of Saltykov's theorem. As a result, the mean diameter of the cell cross sections showed a linear relationship with the mean diameter of the three-dimensional cells. It was confirmed that cell structure of the foam, which should have been analyzed taking into account of the three-dimensional shapes of the cells, was evaluated by analysis of the cell cross sections. The cell number which is measured for the equidimensional hexagonal model is closely related to the cell diameter, and is comparable with the cell number experimentally measured. By examining the relation between the cell diameter and the mechanical properties, a linear relationship was found between the hardness and the cell diameter.View full abstractDownload PDF (2704K) -
Masayuki NAGAI, Hiroki UEHARA, Tetsuo KANAMOTO1996 Volume 53 Issue 9 Pages 555-562
Published: September 25, 1996
Released on J-STAGE: March 15, 2010
JOURNAL FREE ACCESSPoly (vinylidene fluoride) films with a variety of initial morphologies have been drawn by solid-state coextrusion and two-stage drawing. The resultant structure and tensile properties of drawn products have been studied by X-ray diffraction, infrared spectroscopy, dynamic mechanical measurements, and tensile tests. It was found that the ductility and the crystal structure of the resultant drawn products were significantly influenced by both the initial morphologies and the drawing techniques. Solid-state coextrusion of GEL (10 wt%) films slightly below the melting point produced oriented films with only the crystalline form; those have a high chain orientation with fc=0.993, and a higher crystallinity of 55%. The chain orientation and crystallinity of such samples were significantly higher than those of the β form samples usually prepared by cold-drawing of a melt-quenched film. Further, the highest achieved tensile modulus and strength at room temperature of 9.0 GPa (dynamic modulus at 35 Hz of 10 GPa) and 0.90 GPa, respectively, were obtained by two-stage drawing of GEL films. Such a tensile modulus corresponds to approximately 1.4 times the highest previously reported modulus value of 6.5 GPa. The fairly low ductility of PVDF is ascribed to the crystal transformation from the initial soft α-crystal form to the hard β-form during deformation.View full abstractDownload PDF (2788K)
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