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Volume 38, Issue 11
Displaying 1-14 of 14 articles from this issue
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Masuhiro Tsukada, Guy Bertholon, Kiyoshi Hirabayashi1982 Volume 38 Issue 11 Pages T451-T456
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSIn order to elucidate the polypeptide model, which is closely related to a modification of silk of bombyx mori, the molecular structure of poly(Gly-L-Ala) and copoly(L-Ala-Gly, L-Ser-Gly) (2:1) have been studied by x-ray powder diffraction, infrared spectra and circular dichroism. The main interests are focused on the effect of introducing the seril residue into the polypeptides chains. A marked similarity between x-ray powder patterns, and CD spectra in the DCA-TFE mixture suggest that poly(Gly-L-Ala) bears a marked structural resemblance to copoly(L-Ala-Gly, L-Ser-Gly) (2:1). However, in the amide I region, a strong infrared band comparing with that of poly(Gly-L-Ala) at 1695 cm-1 in copoly (L-Ala-Gly, L-Ser-Gly) (2•1) assigned to the antiparallel beta structure are observed. The principal advantage of the effect on introducing the seril residues into the polypeptide backbone's chain can be summarized as follows. The backbone chains of copoly (L-Ala-Gly L-Ser-Gly) (2:1) holding at the position of Cα atoms of seril residues crystallize into cross beta structure or antiparallel beta form, while that of poly (Gly-L-Ala) possesses a slight amount of antiparallel beta structure.View full abstractDownload PDF (312K) -
Hirohisa Yoshida, Yasuji Kobayashi, Reiko Yoshida1982 Volume 38 Issue 11 Pages T457-T464
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSMigration of acrylonitrile monomer from styrene-acrylonitrile copolymer of food container into the five kinds of food simulants was studied. It reveals that migration process is made up by two kinds of diffusion steps. The initial step is believed to be the migration process from the non-plasticized polymer and the second step from the solvent-plasticized polymer. These migration processes were affected by the concentration of ethanol and by annealing at the temperature just below its glass transition temperature, e. g. 80°C. The diffusion coefficient, which was calculated from the Fickian equation, increased linearly with increasing the concentration of ethanol. The swelling capacity of the copolymer with the solvent was reduced by annealing. The diffusion coefficient of the annealed specimen at the initial step became one-half of that of the original one by annealing at 80°C for 65 hrs.View full abstractDownload PDF (488K) -
Akira Takaku, Shun Terui, Chiaki Suzuki, Jiro Shimizu1982 Volume 38 Issue 11 Pages T465-T471
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe effect of heat treatment on the dynamic mechanical properties of polyacrylonitrile (PAN) was investigated in connection with whether the change of the mechanical loss tangent (tan δ) peak at 160°C at the earlier stages of heat treatment can be attributed to thermal degradation proceeding preferentially in accordance with the ordering in polymer structure. The temperature dependence of the dynamic mechanical properties of the PAN films and fibers heat-treated at 220°C and 260°C for various periods, respectively, were measured at a constant frequency of 110Hz. The infrared absorbances at specified wave numbers and x-ray scatterings of those samples were also measured to characterize the chemical and physical changes of the polymer structure with heat treatment. The tan δ peak at 160°C decreased its peak height eminently by heat treatments for shorter periods, and simultaneously the x-ray scattering peaks at the Bragg angle 2θ=17.0° and 2θ=29.5° sharpened, whereas neither the infrared absorbance due to a carbon-carbon double bond nor the absorbance due to a carbon-nitrogen triple bond made a significant change. This indicates that the thermal degradation in PAN will not be a major cause of the decrease of the tan δ peak at 160°C. It is considered that the decrease of the tan δ peak at 160°C with heat treatment will be due to the change of the less ordered region to the ordered region, and that in thermo-degradative treatment under the proper conditions PAN will go through a step where the chain-to-chain lateral order augments, before the cyclization due to polymerization of the nitrile side groups proceeds substantially.View full abstractDownload PDF (464K) -
Takatoshi Kinoshita, Akira Takizawa, Yoshiharu Tsujita1982 Volume 38 Issue 11 Pages T472-T478
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSTo investigate the interaction between side chains of glutamic acid residues in a series of copolymers of L-glutamic acid and methyl L-glutamate, the IR spectra, the dynamic mechanical behaviors and the permeation characteristics were studied. The presence of hydrogen bonding between CO2H groups was confirmed by the IR absorption bands at 1720cm-1 being characteristics of the side chain CO stretching and also at 2700 cm-1 of restricted OH stretching for a 30/70 copolymer membrane (30/70=molar ratio of glutamic acid and methyl 1-glutamate). This side chain interaction gives a characteristic mechanical relaxation peak for a 17/83 copolymer and a 30/70 copolymer at about 70°C (0.25Hz). Poly(γ-methyl L-glutamate) (PMLG) has no such a relaxation peak in a similar temperature range. This mechanical relaxation behavior was almost consistence to the result that the OH stretching peak at 2700cm-1 was disappeared at 80°C. The relaxation peak of the copolymers which contain a certain amount of water was observed at room temperature. One of the copolymers, a 17/83 copolymer has the relaxation peak at 30°C when the relative humidity p/p0 was fixed at 0.5 and at 14°C for p/p0=0.65. In case of a 30/70 copolymer, the relaxation peak was observed at 28°C for p/p0=0.4. The mechanical loss of these copolymers could be investigated as a function of water, methyl alcohol and ethyl alcohol concentration at 25°C. The amount of solvent raising the relaxation peak in each system suggests that the hydrogen bonding interaction between two glutamic acid residues could be broken by about one solvent molecule. The order of the strength of this plasticizing effect is methyl alcohol>ethyl alcohol>water. The temperature dependence of the permeabilities of water vapor through a 17/83 copolymer membrane has an inflection point at about 30°C, which was attributed to the beginning of L-glutamic acid side chain motion. This permeation behavior was also consistence to the results of the mechanical relaxation measurements.View full abstractDownload PDF (431K) -
Masaki Miyamoto, Kenji Honda, Shigeru Sasakawa1982 Volume 38 Issue 11 Pages T479-T483
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSWe have evaluated the compatibility of various fibers as the leukocytes separators by the quantification of the amounts of enzymes which were leaked from adhering granulocytes to fibers. When granulocytes adhered to synthetic and natural fibers, changes in the shape of adhering cells and leakage of lysosomal enzymes were observed, depending on the chemical and physical structure of fibers. However, morphological changes and enzyme leakage were not always correlative. Physical factors such as the diameter and the shape of fibers were important. These changes increased as the diameter of fibers decreased. They could be suppressed by coating the surface of fiber with albumin.View full abstractDownload PDF (1631K) -
Akira Takahashi, Sugahara Yasusato, Kikuo Hozaki, Shiro Takahashi1982 Volume 38 Issue 11 Pages T484-T490
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSNone catalytic photo-induced graft copolymerization of methyl methacrylate onto acetylcelluloses having a different combined acetic acid content has been studied.
The degree of grafting and the number of grafted chains increased at a lower combined acetic acid content, corresponding to a lower degree of polymerization. These values using a quartz tube were greater than those using a pyrex tube. In case of regenerated cellulose, the degree of grafting also increased with decreasing the degree of polymerization.
Adding a small amount of solvent in the polymerization system generally increased the degree of grafting and the branched chain length, but adding more decreased these values. Furthermore, the chain transfer constants to the solvent and to the trank polymer were determined. The ultraviolet photolysis of acetylcellulose was also investigated by the infrared spectra.
From these results, it is concluded that the grafting proceeds at the chain ends of trank polymer and the grafting started by the photolysis of acetyl groups is denied.View full abstractDownload PDF (414K) -
TOSHIRO MASUDA, MASAOKI TAKAHASHI1982 Volume 38 Issue 11 Pages P491-P498
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
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Yoshio Tanaka, Hideki Shiozaki1982 Volume 38 Issue 11 Pages T491-T499
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe heterogeneous addition reaction of di- and trifunctional epoxides with wool keratin was investigated in carbon tetrachloride and toluene at 50-75°C, by using an aqueous solution of various salts as padding catalysts. The reaction rates depended on the nature of the salt, the epoxide and the solvent, and on the temperature. The rate increased with the salt concentration and reached a maximum value at a certain concentration of the salt. The effect of salt was attributed to the basicity or the nucleophilicity of the anions. The weight gains were described mainly by the reaction of the epoxide with the hydroxyl groups of the tyrosine and serine residues, although lysine, histidine, arginine and cystine residues were found to react. The wool fabrics treated with the epoxides were imparted with lower solubility in HCOOH/H2O2 and NH4OH solutions, and with poorer resistance to aqueous NaOH solutions.View full abstractDownload PDF (591K) -
JIRO SHIMIZU1982 Volume 38 Issue 11 Pages P499-P507
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
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Kensaku Mizoguchi1982 Volume 38 Issue 11 Pages T500-T506
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe simulation model offered in the previous paper was extended and effects of operation conditions on levelness of rope dyeing were investigated in more detail.
From the analysis, effects of operation conditions on degree of dyeing levelness were arranged apparently, and in addition, following suggestions were obtained in relation to level dyeing:
1) Unlevel dyeing occurs strongly in a certain stage of dyeing.
2) Degree of dyeing levelness depends on the parameter β which relates to flow conditions of dye liquor.
3) In the stage of constant end point temperature, it is suggested that to suppress flow of dye liquor is desirable from the view point of preventing unlevel dyeing.
4) From 1) to 3), an optimal flow condition of dye liquor is suggested.
5) Temperature rising rate dT/dt also gives strong effects on degree of dyeing levelness.
6) If dyeing is performed under a constant dT/dt, lower end point temperature is suitable to avoid unlevel dyeing.View full abstractDownload PDF (407K) -
Shigeo Hirose, Tatsuko Hatakeyama, Hyoe Hatakeyama1982 Volume 38 Issue 11 Pages T507-T511
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
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MICHIKAGE MATSUI1982 Volume 38 Issue 11 Pages P508-P513
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSDownload PDF (1670K) -
HIROSHI YASUDA1982 Volume 38 Issue 11 Pages P514-P520
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSDownload PDF (2195K) -
KATSUMI HASEGAWA1982 Volume 38 Issue 11 Pages P521-P527
Published: November 10, 1982
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSDownload PDF (1099K)
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