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Volume 23, Issue 6
Displaying 1-8 of 8 articles from this issue
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(III). SMALL ANGLE DIFFRACTION PATTERNS OF REDRAWN FILMMasataka Kurokawa, Takashi Konishi, Hajime Sakano, Muneo Kondo1967 Volume 23 Issue 6 Pages 247-253
Published: June 10, 1967
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSAs previously reported, the redrawing mechanism of drawn polyethylene film depends upon the structure of the original drawn film and the temperature of redrawing. We have examined the structure of redrawn film with the small angle X-ray diffraction method. When the drawn film is redrawn through a sharp kink plane, its small angle patterns change from a streak-like pattern on the meridian of the original drawn region to a weak distorted four points pattern in the redrawn region. By annealing at freely contractable condition, the pattern varies to oblique two point pattern which is a part of ordinary four point pattern. But by annealing at fixed condition, it varies to ordinary four point pattern. When the film is redrawn without the formation of kink band, the small angle pattern of redrawn region is a streak-like distorted pattern which restores its original streak-like pattern on the meridian by annealing at freely contractable condition, but does not restore by annealing at fixed condition. From the difference of small angle pattern caused by the redrawing, one may conclude that the clear difference of redrawing mechanism exists in these two cases.
The condition of annealing, freely contractable of fixed, also affect the small angle pattern of redrawn and annealed film. External or internal stress acting upon the molecular chains during annealing will influence upon the recrystallization of redrawn film. Similar two point oblique pattern are observed when the polyethylene film with a-axis orientation is obliquely drawn and freely annealed. In both cases two point pattern will be formed by the structure recrystallized under the influence of shearing stress.View full abstractDownload PDF (3866K) -
(1) PRORERTIES OF POLYBUTENE-1 AND ITS COPOLYMERSFumio Sakaguchi, Waichiro Tsuji, Takashi Yamazaki, Toshio Kitao, Shogo ...1967 Volume 23 Issue 6 Pages 254-259
Published: June 10, 1967
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSMechanical properties of fibers and films of isotactic polybutene-1 and its copolymers were studied in relation to the crystalline transformation of the Form II to Form I.
No difference in the tensile strengths of fibers and films was recognized for the both crystalline forms, but there is a remarkable difference in the tensile elongation. Polybutene-1 fiber of the Form II shows much more drawability than that of the Form I. It is known that molecular and crystalline orientations in polybutene-1 fiber are more affected by drafting in melt-spinning than by drawing after spinning on account of accelerated transition due to drafting of the Form II to Form I.
An interesting feature of the copolymers of butene-1 with 3-methyl-1-butene or 4-methyl-1-pentene is an ability to cocrystallize in type of the Form II of polybutene-1. Though it is known that the Form II of butene-1 homopolymer is less stable at room temperature than the Form I, it was found that the Form II of those copolymers is stablized owing to incorporation of those comonomer units into the crystal lattice of the Form II. Therefore, it is expected to improve the adverse properties such as the difficulty of drawing after spinning and the devitrification caused by crystal transition of polybutene-1 without lowering of its melting point, tensile strength and flexibility.View full abstractDownload PDF (398K) -
(1) THE WEDGE EFFECT OF SOLID LUBRICANT ON THE LUBRICATION OF NYLON FIBREEiichi Kuze, Teruo Furushima1967 Volume 23 Issue 6 Pages 260-264
Published: June 10, 1967
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe frictional behaviours of the fibres lubricated with a solid lubricant have been studied. When the lubricant film between the sliding bodies is thinner, it is found that the solid lubricant has a wedge effect to the sliding bodies.
a. An increase in sliding speed increases the shear strength of the lubricant film, and thus the wedge effect is improved.
b. When the sliding bodies are lubricated with a bad lubricant from which intimate contacts of the bodies come, the intimate contacts decreases by an increased sliding speed. Then, the friction decreases as sliding speed increases.
c. It is apparent that the coefficients of friction for given speed are related to the figure of the surface of sliding body and its friction index.
d. Lamellar state of lubricant film is suggested by the change of friction index with sliding speed.
e. The wedge effect is stronger if the added lubricant on sliding bodies is thicker.View full abstractDownload PDF (411K) -
(2). THE QUASI-HYDRODYNAMIC EFFECT OF SOLID PARAFINE ON THE LUBRICATION OF FIBREEiichi Kuze, Teruo Furushima1967 Volume 23 Issue 6 Pages 265-268
Published: June 10, 1967
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSWhen the lubricant film between the sliding bodies is thicker, the solid lubricant may show a quasi-hydrodynamic behaviour.
It is assumed that the shearing force of lubricant film F is given as follows; where, U: the shearing speed, h: the thickness of lubricant film, A: the area of the film, υ, α: the constants depending on lubricants.
Then a formula of quasi-hydrodynamic lubrication may be expressed as follows; where, fi: frictional force that acts on the unit length of fibre or yarn, Ri: load that acts on the unit length of fibre or yarn, c, N: constants.
The formula is found to have a reasonable agreement with the experimental results.View full abstractDownload PDF (230K) -
(PART II) THE CHANGES IN ORIENTATION AT DRAWING PROCESSKenji Kamide, Yoshihiko Inamoto, Kunio Ono1967 Volume 23 Issue 6 Pages 269-276
Published: June 10, 1967
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe effect of molecular weight and drawing conditions (temperature, draw ratio) on the molecular orientation in amorphous and crystalline parts in polypropylene fiber were studied by birefringence, wide angle X-ray and density. The two kinds of undrawn filaments, one having the molecular weight 5.8×104 (birefringence; Δn=2.0×10-3, crystal form; smectic) (I) and the other of 18.0×104 (Δn=1.0×10-2, monoclinic) (II) were stretched at six temperatures in the range from a room temperature to 140°C. Being stretched at a room temrerature, the X-ray diffraction pattern of both sampes at equator becames broader in high draw ratio region, but at higher temperature, it stays sharp even in high ratio of draw. The above results are consistent with those reported in Part I of this study. The smectic form in filament (I) is converted into monoclinic form during the draw process, if the temperature is higher than 90°C. In this case, the c-axis of crystallite orientates in the direction of fiber axis with the increase in draw ratio. By Wilchinsky's method, the orientation parameter of crystalline <cos2σ>av was obtained from an azimuthal scan over intensity of (040) and (110) reflection. <cos2σ>av increases with the draw ratio, however its dependence upon the draw ratio differs with molecular weight. <cos2σ>av decreases with the draw temperature. There is a considerable correlationship between <cos2σ>av and Δn. The correlation between <cos2σ>av and Δn differs with molecular weight, which may be due to the dependence of shrinkage behavior on molecular weight. The orientation factor of crystallite fc obtained from fc=(3 <cos2σ>av-1)/l is generally larger than that of amorphous chains fa calculated from the experimental data on birefringence, crystallinity and from theoretical values of the birefringence of perfect crystallite and perfect amorphous chains, (Δnc)0, (Δna)0. Δnc plays more predominant role in Δn than in Δna, irrespective of molecular weight which suggests that the orientational relaxation of drawn filament during shrinkage at a room temperature occurs mainnly in amorphous region.View full abstractDownload PDF (1745K) -
(PART III). NECKING PHENOMENA AND STRETCHING STRESS-BIREFRINGENCE RELATIONSKenji Kamide, Kiyoshi Fujii1967 Volume 23 Issue 6 Pages 277-282
Published: June 10, 1967
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThis present paper intends to investigate necking phenomena occuring in stretching polypropylene filament and to study on stress-birefringence relations during stretching taking into consideration of the effects of molecular weight and molecular weight distribution.
Six kinds of polymer fractions ranging in molecular weight of 4.24×104 to 25.1×104 and unfractioned sample of molecular weight 18.0×104 were used. Samples were meltspun under same conditions except spinning temperature to get 30 denier filament.
Results obtaind are summerized as follows:
(1) Necking is manifested very sharply with decrease of molecular weight and of stretching temperature.
(2) Transverse lines in the stretched filament are observed when stretching is sufficiently large almost close to its breaking point. The distance between neighbouring lines becomes far apart with rise in stretching temperature. Transverse lines becomes not clear with increase in molecular weight.
(3) Relationship between stress and birefringence strongly depends on molecular weight even under same stretching conditions. The force for molecular orientation increases remarkably with increase in molecular weight.
(4) Birefringence of filament increases with stretching stress up to the assymptotic value, (Δn)max. (Δn)max for stretched filament at room temperature, at first, rapidly increases then decreases with increasing molecular weight. On the other hand, (Δn)max at 120°C continuously increases with molecular weight. It holds that (Δn)max at room temperature <(Δn)max at 120°C for filament of same molecular weight.
(5) After stretching birefiringence in filament was found to be reasonably constant over the time investigated in spite of fast relaxation of stress when the ends of filamentis fixed at constant distance.
(6) Increase in molecular weight gives more pronounced degree of shrinkage in length when the stretched filament is kept at natural length.View full abstractDownload PDF (2243K) -
Shuichi Uchiyama1967 Volume 23 Issue 6 Pages 283-290
Published: June 10, 1967
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSThe dry spinning condition to obtain continuous filaments of polyacrylonitrile from dimethylformaide solution was investigated as to residual solvent, yellowness (YI) and longitudinal dispersion of denier of undrawn filaments.
In this study, length and diameter of the spinning tower were fixed. Results obtained are;
1) The higher the temperature of hot air and spinning tower, the smaller the residual solvent content; and the increase of hot air intake results in the decrease of the residual solvent content of the undrawn filaments.
2) The spinning solution with larger yellowness (YI) results in the undrawn filaments with larger Yl obtained under the same spinning condition.
3) The larger the volume of hot air, the higher the concentration of the spinning solution and the smaller the spinning draft, the smaller is the longitudinal dispersion of denier.
Optimum range for temperature and concentration of the spinning solution, and temperature of hot air also results in the smaller dispersion of denier.
4) The dispersion of denier is not so much influenced by the viscosity of the spinning solution.
5) The larger initial drying rate of dimethylformamide from the extruded filaments, which is thought to be proportional to the constant drying rate, makes the longitudinal dispersion of denier smaller.View full abstractDownload PDF (468K) -
(III). DYEING PROPERTIES OF CHLORINATED POLYOLEFINE FIBRES (PART I)Izumi Fumoto1967 Volume 23 Issue 6 Pages 291-298
Published: June 10, 1967
Released on J-STAGE: November 28, 2008
JOURNAL FREE ACCESSPoly-ethylene, -propylene and -butene-1 fibres were chlorinated by chlorine gas, chlorine aqueous solution and by calcium hypochlorite which was activated by HCl, with or without exposure to light at 20°C.
With the low chlorinated fibres (less than 5% chlorine content) a decrease in tensile strength and the degradation of polymers were not recognized. A decrease in breaking elongation and an increase in Young's modulus, however, were appreciable, i. e. the chlorination made the fibre harder than the original one.
The chlorination had a pronounced effects on the dyeing properties of polyolefin fibres for cationic dyes. The chlorinated fibre could be easily dyed with cationic dyes under the suitable condition.
The physical and chemical characteristics of the chlorinated fibres concluded from this work are as follows:
1) The infra-red spectrum of chlorinated fibre contains a broad and weak absorption over the 600_??_700cm-1 range. This absorption is characteristic for chlorinated fibre and may be due to C-Cl linkage. New absorptions arising from the other linkage are not recognized.
2) Not all of the chlorine atoms in the chlorinated fibre are chemically bonded with the fibre, but some of them are merely adsorbed physically on the internal surfaces of the fibre, presumably in the form of HCl.
3) The crystallinity of the chlorinated fibre decreases with the degree of chlorination, but the birefringence fluctuates unsystematically.
4) The chlorination might occur selectively on the outer surface of the fibre.View full abstractDownload PDF (975K)
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