The effects of fillers on environmental stress cracking of high-density polyethylene have been investigated. The samples filled with four kinds of inorganic fillers were prepared. The samples with a single notch and unnotched samples were fractured under constant loads in methanol environment. The relation between stress and fracture time has been studied by using unnotched samples. Furthermore, the relation between the stress intensity factor and crack propagation rate has been studied by using notched samples. From these relations, we discuss the effects of fillers on fracture behavior of high-density polyethylene in methanol environment.

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In order to investigate the difference in moisture adsorptivity between the three hydroxyl groups in cellulose-glucopyranose unit, the moisture sorption isotherm and the heat of moisture sorption were observed for a series of cellulose acetates over whole range of relative humidity from dryness up to saturation at 30°C. The series of cellulose acetates, including a regenerated cellulose and a tri-acetate as extremes, were well-defined in terms of the partial degrees of substitution of the three hydroxyl groups, <f_i>, where i is 2, 3, or 6 indexing the carbon atom to which the hydroxyl group is bonded.
It was revealed that the B. E. T.'s multilayer adsorption model was not applicable to the analysis of the isotherm not only for the cellulose acetates, but even for the regenerated cellulose, explicitly, at low relative humidities of less than 5%. The isotherms in the low humidity range were analyzed successfully by a composite isotherm model of three components; D'Arcy and Watt's model composed of two Langmuir terms and a linear term. One of the two Langmuir terms with relatively large adsorptive energy factor, the other Langmuir term with relatively small adsorptive energy factor, and the linear term, were attributed to the adsorptions due to OH-6 (the hydroxyl group bonded to the C-6 carbon), to OH-2, 3 (the hydroxyl groups bonded to the C-2 and C-3 carbons), and to OAc-2, 3, 6 (the substituted acetyl groups), respectively.
The differential heat of moisture sorption at dryness, Q_L(α=0), was found to decrease sequentially with increase in the total degree of substitution; from 341±22 for the regenerated cellulose to 184±10 cal/gram of liquid water for the tri-acetate. Assuming the differential heat of moisture sorption in bulk at dryness to be simple sum of these of the polar groups, the Q_{L, OH-6}(α=0), Q_{L, OH-2, 3}(α=0), and Q_{L, OAc-2, 3, 6}(α=0) were determined as 383, 320, and 180cal/gram of liquid water, respectively, in good accordance with the above assignments of the three kinds of moisture adsorption mechanism, at least qualitatively.

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Chitosan membranes with various degrees of deacetylation were prepared by casting acetic acid solutions of chitosan. The effective charge density on the membranes was calculated by Teorell-Meyers-Sievers theory from the membrane potential determined with potassium chloride. The charge density unexpectedly decreased with the increased deacetylation, suggesting the influence of decrease of the amorphous regions containing dissociable amino groups. The permeability of the membranes was determined for four simple electrolytes. At low electrolyte concentrations, permeability increased with the concentration through the Donnan effect. At high concentrations it became independent of ionic concentration and was negatively dependent on the radii of hydrated ions. The microporous membranes showed 2-3 times higher permeability than the dense membranes, while their concentration dependences were similar to each other.

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In order to know the difference in the diffusion behaviour of dye molecules in porous and less porous polymer substrates, investigations were carried out by two different ways; i) Sorption rates of p-aminoazobenzene (p-AAB) on porous acrylic fibers Aqualon WM1 and less porous acrylic fibers Acryl RK1 from the aqueous solution were measured in the range of 65 to 100°C, and ii) the change of diffusion profile of p-AAB in porous and less porous polyacrylonitrile (PAN) membrane assemblies was examined at 60, 70 and 80°C as a function of diffusion time.
From the evaluation of these data, it was proved that for the porous PAN substrates, the dye molecules diffuse rapidly through pore liquid and simultaneously in the polymer matrix with slow rate, while for the less porous substrates only the slow diffusion can take place exclusively in the polymer matrix.

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When an observer rates whether clothes are well-becoming to the wearer or not, his rating must be usually based on the recognition of certain visual factors characterizing the clothes and wearer. The purpose of this article is to look for such factors being essential to the visual rating of becomingness and to establish a mathematical model that can elucidate the mechanism of rating. In the previous model, the final total rating is estimated only by simple addition of the rating scores of many elemental factors, so that the effect of crossing between the factors can not be taken into account. The present approach can treat the effect of interaction between the factors of wearers and clothes.
A set of words, adjectives in Japanese to represent the visual images of clothes and of wearers were chosen, eithteen and twenty pairs of words were adopted for clothes and for wearers, respectively. A hundred test clothes, fifty nine test wearers, and thirty eight observers were prepared for the rating experiment.
The degree of becomingness was graded into three degrees by the sensory test. From a factor analyzed the results of rating, five common factors were induced for clothes and six were for wearer. A calculation scheme was established to express the criterion of rating on becomingness in terms of those common factors. It was found that this method was able to elucidate the cross effect of visual factors between the wearers and the clothes and gave a good estimation to the actual becomingness.

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The tension of running yarn during twist setting with a heating plate was studied in terms of the original yarn's physical properties.
The results obtained are as follows:
(1) The heat shrinkage of the original yarn caused by heating in the static state is influenced by the thermal hysteresis during spinning process, and this phenomenon depends on the characteristics of the original yarn. However, in the case of the hard twist yarn, the shrinkage did not occur, because the effects of twisting torque and elasticity caused by its spiral shape are large.
(2) When the circumferential velocity of a feed roller equals a delivery roller's velocity, the tension during heat-setting can be estimated by the distance of the rollers, heater length and stress-strain behaviour of twist-setted yarn.
(3) When the yarn tension during re-heating is too large, the twisting torque does not appear, because molecular chains begin to flow. Accordingly in order to obtain the high-quality crepe fabric, it is necessary to determine the scouring condition considering the twist-set temperature and the thermal hysteresis of the original yarn.

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Commercial nylon 66 fiber was dipped in a chloroform solution of dicumyl peroxide (DCP) by refluxing under N₂ atmosphere for predetermined days and then it was heated at 150°C for 2hr resulting in crosslinking. The fiber became insoluble in hot formic acid after 5 days of dipping. By the treatment the crystalline region was little changed and a part of DCP was crystallized in the amorphous region. Tenacity and elongation decreased and modulus increased with crosslinking. Upon water absorption, decrease of tenacity and elongation was not observed for the crosslinked fibers.

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Neutron scattering was used to investigate the network structure and the response of network to deformation in epoxies. Partially deuterated diglycidyl ether of bisphenol A was cured both with and without amine curing agents. The difference in scattering intensity between cured materials and the monomers will be discussed. The change of the average distance between crosslinks due to deformation and solvent swelling was measured and the results will be discussed in terms of an network unrolling model.

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