巻号一覧
26 巻, 12 号
選択された号の論文の6件中1～6を表示しています
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松本 喜代一, 佐藤 浩三, 石井 浩一, 今村 力造1970 年 26 巻 12 号 p. 537-549
発行日: 1970/12/10
公開日: 2008/11/28
ジャーナル フリーThis report shows the effects of crystalline orientation on the mechanical properties of the biaxially stretched polypropylene films prepared by dry-process.
In this study, polypropylene fiims T-die extruded with 150μ thickness and random orientation were used. In a recirculating hot-air bath at 145°C, and at constant rate 1600%/min, the films were stretched to various extensions using the filmstretcher, (i.e., uniaxially stretched under the conditions of free width and/or constant width, two-way successively, and simultaneously biaxially stretched), and then heat set at 150°C for 10min.
Mechanical properties of the variously stretched films were evaluated by stress-strain curves measured at 20°C, 65% R. H. On the other hand, the behaviors of crystalline orientation and crystallization in these stretched films were investigated by the x-ray diffractogram and density measruement.
The following results were obtained:
(1) The crystalline orientation of uniaxially stretched films under the conditions of free width has uniaxial orientation of which crystal c-axis is oriented parallel to the tensile axis, cylindrical symmetry around the stretching direction, as a fiber. For the uniaxially stretched films with the constant width, however, the crystallites have uniplanar-axialy orient in the way that the c- and a′-axies orient parallel to a filmsurface plane and the c-axis parallel to the tensile axis. The difference of both mechanical properties was connected with that of the orientation.
(2) The crystalline orientation of two-way successively biaxially stretched film varied depending on streching ratio, that is by successive stretching to transverse directon, the initiial uniplanaraxial orientation changes into the intermitted state, and finally approaches to the uniplanar-axial orientation to a transverse dirction. During the stretching, the crystallite begins to turn to transverse direction, and this process is presumably related to the unfolding of crystals. After the “blance point”, rectystallization seems to take place.
(3) The crystalline orientation of simultaneously biaxially stretched films is uniplanar orientation at all stretch ratio. Therefore, the equal mechanical properties are obtained within the stretched plane at all stretched ratio.抄録全体を表示PDF形式でダウンロード (3706K) -
小林 重夫1970 年 26 巻 12 号 p. 550-559
発行日: 1970/12/10
公開日: 2008/11/28
ジャーナル フリーThis paper describes the necking phenomena of undrawn polyester fibers in stretching under various conditions in the vieinity of glass transition temperature. Neck ungle is used as a parameter whichexpresses the characteristics of the necking geometry. This parameter means the angle between the direction of the necking shoulder and the fiber axis. The neck angle is very sensitive to the temperature and propagation rate. The plots of necking angle against the propagation rate abtained at different temperatures cone be superimposed to a master curve by shibting the plot along the rate axis. The shift factor log aT-temperature relationship agrees quite well with the WLF equation, with exception at temperatures lower than the apparent Tg under external force.
The necking phenomena are characterized by the necking draw ratio, the necking tension and the birefringence of the necking region. These factors depend a priori on the neck angle irrespective of the drawing condition.
Finally, it must be recognized that the necking is a relaxation phenomena within a large wale of temperature and therefore the necking always occurs at temperatures lower than Tg even in the very low rate of stretching.抄録全体を表示PDF形式でダウンロード (1923K) -
松崎 啓, 中村 茂夫, 塚本 治夫1970 年 26 巻 12 号 p. 560-566
発行日: 1970/12/10
公開日: 2008/11/28
ジャーナル フリーCellulose acrylate acetate, which has double bonds in the side chain, was synthesized and methyl methacrylate was grafted onto the cellulose ester in the homogeneous systems using benzoyl peroxide as an initiator and dioxane or cyclohexanone as a solvent.
The following results were obtained:
1) Grafting efficiency was low and was 28.1% at the most. The values at 80°C were larger than at 60°C. At 80°C the grafting in dioxane as a solvent resulted in a higher degree of grafting compared to that in cyclohexanone, but no difference was observed among solvents at 60°C.
2) The formation of homopolymer was larger at 80°C than at 60°C, and no difference was observed among solvents.
3) Although the reaction was carried out in the homogeneous systems, in which both the trunk polymer and the graft copolymer were dissolved, a number of grafted side chains per trunk polymer was less than unity irrespective of the reaction conditions. This is supposingly attributed to the difficulty of the attack on initiator and propagating polymer radicals on double bonds in the cellulose esters due to the steric hindrance of acetyl groups existing in the cellulose ester, and consequently the smaller reactivity of double bonds in this cellulose ester.
4) The graft copolymerization was also carried out using cellulose acetate instead of cellulose acrylate acetate under the same reaction conditions. Almost the same amount of homopolymer was obtained as in the case of cellulose acrylate acetate, but no graft copolymerization occurred. Accordingly, the double bond in acryloyl group was definitely involved in the reaction.
5) The grafted side chains could be perfectly isolated from the graft copolymers by hydrolyzing the trunk polymer for 12 hours at 105°C using a dioxane-HCl system which can dissolve both the graft copolymer and the side chain polymer.抄録全体を表示PDF形式でダウンロード (476K) -
滝沢 章, 根岸 孝雄, 石川 欣造1970 年 26 巻 12 号 p. 567-570
発行日: 1970/12/10
公開日: 2008/11/28
ジャーナル フリーThe interaction between amorphous non-polar polymer and non-polar solvent was examined using atactic polypropylene-n-paraffine systems with sorption method. In the higher relative vapor pressure region of sorption isotherm, the smaller the solvent molecule is, the more is it sorbed. The Flory-Huggins' parameter X1, is not constant in these systems over the whole relative vapor pressure range. In the case of polypropylene-n-pentane system, X1 versus pressure relation has a maximum, while that of the golypropylene-n-heptane system has a minimum at certath relative vapor pressures. These trends are explained by the combination of surface adsorption mechanism, increase of affinity of polymer to solvent with increase of pressure, and swelling effect (effect of elasticity of polymer network chains) which resists sorption.
The sorption isotherm of polypropylene-n-heptane system at 25°C is lower than that at 35°C. From the X1 vs. P/P0 relations, it is observed that when the temperature is low, the effect of swelling mechanism becomes remarkable because the region which does not contribute to the sorption increases.
It is clear that the atactic polypropylene has the distinct cohesive energy distribution, and from lower to higher cohesive energy region in succession, the polymer achieves a mare stable solvated state by the dissolving action of solvent.抄録全体を表示PDF形式でダウンロード (270K) -
秦 邦男, 横田 金吾1970 年 26 巻 12 号 p. 571-577
発行日: 1970/12/10
公開日: 2008/11/28
ジャーナル フリーPrevious work in this series has shown the preparation of cellulose-liq. SO2 solution in the presence of amine1) and a few properties of solutions under various conditions have also been reported2).
The present work was undertaken to investigate the effects of amines for viscosities of cellulose solutions. Diethylamine, triethylamine and piperidine were employed as dissolving aid for cellulose. Viscosities of the solutions were measured with capillary viscometer specially designed for liquid SO2.
In the above examination, it was observed that the reduced or intrinsic viscosities of the cellulose solutions containing ethylamine or piperidine were higher than those in which containing triethylamine. The solutions using free secondary amines became more viscous with increase of amine concentration and became less viscous by adding amine hydrochlorides. The similar phenomenon was observed on gelatinizing temperature of the cellulose solutions using secondary amines.
Meanwhile, the viscosity of cellulose solution using triethylamine was scarcely effected by the concentration of amine or by the addition of amine hydrochloride. The solution (cellulose 0.15g, triethylamine 0.1 mol, liq. SO2 100ml at 20°C) was not gelatinized even at -60°C, though the solution of the same composition prepared with diethylamine was gelatinized at -14°C.
Consequently, in view of the above facts the most reasonable conclusion to be drawn from available data is that the viscosity behaviors of the cellulose-SO2 solutions prepared with secondary amine are quite different from those of which prepared with tertiary amine. Secondary amine has N-H bonding in its structure (R2NH), and it is a well known fact that the hydrogen atom which directly combined with nitrogen atom is markedly active in liq. SO2. Therefore, in the case of using secondary amine as dissolving aid, the evidence thus obtained supports the suggestion that the cellulose molecule dispersed with amine-SO2 complex into the liq. SO2 is liable to form the intramolecular linkage by hydrogen bonding and the secondary amine-SO2 complex may promote such an interaction in liq. SO2.抄録全体を表示PDF形式でダウンロード (495K) -
松川 三郎, 長瀬 剛司, 佐々木 英夫, 大江 秀雄1970 年 26 巻 12 号 p. 578-582
発行日: 1970/12/10
公開日: 2008/11/28
ジャーナル フリーMerino wool fibers were treated with aqueous sodium bisulfite (a mild breaking agent for cystine cross-inkages) and followed by the treatment with aqueous alkali (an attacker for ortho-cortex in wool structure). The crimp force i.e. load (P mg) to pull out crimps of a single fiber and the number of crimps per unit length (cm) of extended fiber without stretching were measured before and after above treatments. Stress-Strain curves of the treated fibers, as well as increments of their elastic and plastic regions were also obtained.
The results are summarized as follows:
1) The treatment with sodium bisulfite solution at 20°C for 30 min did not alter the crimp force and the number of crimps, but treatments at 60°C and 80°C for 30 min minimized the crimp force.
2) The number of crimps in wool fiber treated with sodium bisulfite followed by alkali treatment increased remarkably and the crimp configuration became much more homogeneous.
3) Magnitudes of crimp force per crimp decraesed in the following order (independent of pretreatment); in air > in water > in chemical reagent solutions, and they were inversely proportional to degrees of swelling of fibers in measuring media.
4) Percentages of decrease in elasticity in the elastic regions and increase in plasticity in the plastic regions of a fiber seem to be correlated with degrees of swelling of the fibers.抄録全体を表示PDF形式でダウンロード (1164K)
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