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Volume 28, Issue 8
Displaying 1-8 of 8 articles from this issue
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Koji Terada, Hideji Kitagawa, Koichi Kato1972 Volume 28 Issue 8 Pages 281-288
Published: August 10, 1972
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe birefringence of acrylic fibers was investigated in relation to their fine structure. The signs of the birefringence of fibers made by wet-spinning and subsequently stretched and dried under different conditions were determined by a polarizing microscope. The shape birefringences were investigated by using various immersion liquids and at the same time the fine structure of the fibers were observed by an electron microscope. The results obtained are as follows:
(1) Transparent fibers show negative birefringence irrespective of the immersion liquids.
(2) Two types of opaque fibers exist, one having a porous fibrillar structure all over the cross section and showing a positive ro negative birefringence according to the refractive indices of the immersion liquids, other having an inner porous fibrillar structure covered by a collapsed void-free skin and showing a positive birefringence due to the shape birefringence.
(3) A structure intermediate between the opaque and the transparent fibers exists, exhibiting a characteristic shape birefringence except when water is used as a immersion liquid.
(4) Using some solvents as immersion liquids, one can clearly ebserve that the skin of the coagulated fiber exhibits a positive birefringence, suggesting a molecular centripetal orientation.
(5) With both as coagulated and the stretched fibers, except when observed by using aromatic compounds as immersion liquids, the relation between the birefringence (denoted by retardation) and the refractive index of the immersion liquid follows Wiener's theory quite well, being rather independent of the solvent used in the wet-spinning. The deviation from Wiener's theory is considered due to the adsorption birefringence.
(6) All the commercial acrylic fibers tested showed negative birefringences, which is not consistent with the report that “Orlon” acrylic fiber has a positive birefringence.View full abstractDownload PDF (3079K) -
STUDY ON EQUILIBRIUM THERMAL STRESS AND THE RATE PROCESS OF DRAWN AND HEAT-TREATED NYLON-6 FILAMENTSIwao Matsumoto, Keiroku Fuchino1972 Volume 28 Issue 8 Pages 289-296
Published: August 10, 1972
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSIn the previous paper, the heat-treatment process and viscoelastic properties of the drawn poly-propylene filaments were studied in relation to the heat-treating temperature. It was shown that the change of stress was the unique function of temperature when the samples were kept at a constant drawn length at temperatures below the heat-treating temperature. The change of stress of the drawn and heat-treated nylon-6 filaments was not neccessarily represented as a function of temperature only, but also depended on the abrupt incaease of decrease of the temperature. When the temperature was incereased suddenly from the the room temperature to a given temperature, the stress change of the samples kept at the drawn length was measured as a function of time to obtain the following results:
1) The reduced stress as a function of time is represented by the following equation for the drawn and heat-treated samples. ΔH(=11.24kcal/mal), Tq(=-29°C) and exp Bq(=1.315) are constants. AT0, and Bc, (which depend on draw ratios and heat-treating temperatures) are also constants.
2) As the coefficient of time in eq. (1) follows the Arrhenius' equation, the apparent activation energy ΔH is obtained, which depends on neither draw ratios nor heat-treating temperature.View full abstractDownload PDF (626K) -
Kazuyoshi Okamoto, Tadahiro Yamamoto1972 Volume 28 Issue 8 Pages 297-301
Published: August 10, 1972
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSIn order to study the grafting onto collagen fiber, the polymerization of methyl methacrylate in the presence of collagen fiber (hide powder) was carried out with ceric sulfate as an initiator.
The graft copolymerization proceeded effectively at 40°C and the yield of graft polymer and the efficiency of grafting were high. The graft copolymerization did not occure when the concentration of the ceric salt was below a certain value. When the Ce-, Cr- and Zr-tanned leathers were used, the yield of graft polymer decreased with increased tanning action. The yield of graft polymer decreased with increased pH value. The yield was minimal, when pH was about 3.
On the basis of the results mentioned above, it was considered that the tanning action occurred between collagen fiber and the ceric salt.
The grafting of n-butyl acrylate onto collagen fiber was also studied. In this case, the yield of graft polymer was less than that of methyl methacrylate.View full abstractDownload PDF (375K) -
Akira Katayama, Nobuhiko Kuroki, Yasunori Kitano1972 Volume 28 Issue 8 Pages 302-308
Published: August 10, 1972
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe purpose of this work is to obtain the information on the dyeing behavior of polyester with disperse dyes from a perchloroethylene solution. The absorption isotherms for C. I. Disperse Red 88, azo-type, (I) and C. I. Disperse Red 60, anthraquinone-type, (II) were determined at 5°C intervals from 100° to 120°C, using polyester film. The absorption isotherms obtained were linear for all dyes. From the absorption isotherms, the partition coefficient and the heat of dyeing were calculated. The partition coefficient ranged from 8-14 for dye (I) to 0.6-0.7 for dye (II). These values are much smaller than for aqueous dyeing at the same temperature. The heats of dyeing for dye (I) and dye (II) were -7 and -2 kcal, respectively. These values are larger ca. 4 kcal than for aqueous dyeing. The diffusion coefficient in the substrate for dye (I) and dye (II) were determined at various temperatures by means of film roll method. The polyester film used was pretreated in a blank dyebath at 120°C. The diffusion coefficients thus obtained did not show any dependency on the concentration of the absorped dye in the film. The diffusion coefficient ranged from 2.56×10-9-2.74×10-8 for dye (I) to 1.87×10-8-5.91×10-8 cm2/min for dye (II). These diffusion coefficient are much larger than for aqueous dyeing. From the temperature dependence of diffusion coefficient, the activation energies for diffusion were calculated for dye (I) and dye (II). They were 32 and 17 kcal, respectively, which are smaller than for aqueous dyeing. From the results obtained in this work, a schematic drawing for swollen polyester in perchloroethylene was obtained.View full abstractDownload PDF (508K) -
Hitoshi Akami, Tatuya Kawakami1972 Volume 28 Issue 8 Pages 309-317
Published: August 10, 1972
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSIn this report, the opening energy of cotton tufts in Platt type Blowing Process was measured and the relation between the type of breakage of Blowing machine and the opening energy of tufts is descussed. The measuring apparatus of the opening energy of tufts consists of nip roller, taker-in roller, torque detector, strain amp., integrator and others. It is a kind of entanglement tester.
The entanglement of cotton tufts increases in Hopper type machine while it decreases in Cylinder or beater type machine.
Thus the opening energy of cotton tufts is larger in Hopper type machine than in Cylinder or beater type machines. The increase in the opening energy of tuft is accompanied by the increase in the un-opened nep like tufts in fleece on the taker-in roller.
Hopper type machine contains much un-opened nep like tufts in the fleece than Cylinder or Beater type machine. It was showned experimentally that the degree of the contact of tufts under sligrt compression influences on the opening energy of cottou tufts.View full abstractDownload PDF (2236K) -
Takeo Sone, Takashi Yamazaki, Seigo Oya, Yoichiro Muraoka1972 Volume 28 Issue 8 Pages 318-324
Published: August 10, 1972
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSIt is well known that sulfuric acid used as catalyst in the acetalization of polyvinylalcohol combines itself hard to the polymer. Although combined sulfuric acid has been generally believed to be injurious to the acetal, on the previous study it was shown that when combined sulfuric acid is neutralized it causes no trouble on the acetal, and that in the case of improved dyeing of benzalized vinylon the combined sulfuric acid is very effective as acid groups which have dyeing affinity with a cationic dyes.
This paper concerns with the utilization of the combined sulfuric acid for improved dyeing of formalized vinylon. Highly concentrated sulfuric acid of 22_??_30% was used as catalyst for acetalization in order to introduce a considerable amount of combined sulfuric acid into polyvinylalcohol.
The fiber thus prepared has good dyeing properties, fastness to light and washing. The tensile strength of fiber is just as high as that of the ordinary polyvinylalcohol fibers.View full abstractDownload PDF (487K) -
Izumi Fumoto, Akira Katayama, Nobuhiko Kuroki1972 Volume 28 Issue 8 Pages 325-327
Published: August 10, 1972
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe zeta-potential of fluorinated, chlorinated, brominated and untreated polypropylene fibers (PP) in buffer solutions [at pH 7.0 and 4.1] and in Methylene Blue aqueous solutions [at pH 4.1 and various dye concentrations] was measured at 25°C by the streaming potential method. In the buffer solutions, the fluorinated PP showed much more negative zeta-potential than those of chlorinated, brominated and untreated PP. In the basic dye aqueous solutions, the zeta-potential of the fluorinated PP has a tendency to increase positive zeta-potential than the others. Consequently, it was suggested that the fluorinated PP has a large affinity for organic cations, such as Methylene Blue, having the ability to interact with the fiber surface by van der waals and higher negative charge.View full abstractDownload PDF (169K) -
1972 Volume 28 Issue 8 Pages 828
Published: 1972
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSDownload PDF (58K)
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