Polyester/ether, poly (ethylene-1, 2-diphenoxyethane-p, p'dicarboxylate) (PEET), fibers have been drawn under several conditions. Birefringence of the fibers only depended on draw ratio and crystallinity of the fibers mainly depended on drawing temperature. On the same drawing ratio, crystallinity and lateral crystallite size increased but amorphous birefringence and axial crystallite size decreased with an increase in drawing temperature. On the same drawing temperature, birefringence increased but crystallinity and crystallite size were almost constant with an increase in the drawing ratio. Melting point of the fibers depended both on axial and lateral crystallite sizes. These results could be explained by that highly aligned molecules were laterally well ordered but translationally shifted along the chain, because of long monomeric unit length.
Young's modulus of the fibers mainly depended on the birefringence but not on fiber morphology.

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Relationship between mechanical properties and fiber structure of the high modulus and the high tenacity fibers prepared by continuous zone-drawing and continuous roll-drawing methods were studied. In the zone-drawn fibers, birefringence of amorphous phase frequently exceeded that of crystalline phase. On the other hand, amorphous birefringence was always lower than that of crystalline phase for the fibers prepared by the continuous roll-drawing method. The crystalline block size and the degree of crystallinity for the continuous roll-drawn fibers were larger than those for the zone-drawn fibers. These results could be interpreted by that drawing stress in the zone-drawing is much larger than that in the roll-drawing, so that linkages of crystalline block are well developed and this leads to the high degree of amorphous orientation and the high modulus. Such linkages will be developed as an increase in crystallinity, when the crystallinity exceeds 77%. On the other hand, the tenacity was mainly dependent on the degree of crystallinity and showed almost the same value between the zone-drawn and the roll-drawn fibers.

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High-speed spinning of poly (ethylene terephthalate) has been carried out for take-up velocity up to 10000m/min in order to investigate the process of fiber structure formation. The temperature and diameter of fibers were measured along spinline using optical methods. The birefringence and the X-ray diffraction pattern of the filaments taken-out by trapping in spinline were estimated. In the case of 8000m/min, molecular orientation begins to increase near by the end of necking, where spinning stress is on the order of 10⁸dyn/cm² The molecular orientation of surface layer of fibers preceds to that of central layer. The temperature of fibers along spinline increased below the end of necking. This indicates that crystallization proceeds immediately after the end of necking. The process of growth of fiber crystals during high-speed spinning has been discussed.

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Four kinds of ethylene terephthalate/ethylene isophthalate copolymers (PET/PEI, PEI=0, 2, 5, 10mol%) were prepared and melt spun at take-up velocities from 1 to 7km/min. Birefringence and density of as-spun fibers increased with increasing take-up velocity. Density showed abrupt increase due to oriented crystallization at take-up velocities above 5km/min, where birefringence and density became lower for higher PEI contents. Radial variation of birefringence in filament cross-section measured with an interference microscope was also lower for the higher PET content fibers. Moreover, increase in PEI content caused the decrease in Young's modulus and tenacity and the increase in extension at break. These results suggest that development of fiber structure through the oriented crystallization was suppressed by the existence of the ethylene isophthalate component.
Filament diameter profiles in the spinline were measured using a diameter monitor. Below 4km/min, filaments attenuated smoothly along the spinline, while above 5km/min, neck-like deformation was observed. With increasing PEI content, position of the neck-like deformation moved downward in the spinline, and necking draw ratio decreased. From the relation between the neck-like deformation in the spinline and the physical and mechanical properties of high-speed spun fibers, it is concluded that birefringence, density, Young's modulus, tenacity and extension at break of as-spun fibers are governed by the necking draw ratio, and that the radial variation of birefringence is governed by the position of neck-like deformation.

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A thermodynamic consideration of the coefficient a in the modified Flory's equation (1) for the melting of random copolymers and the transition free energy (f_x) of quasi-crystals in the amorphous regions led to an equilibrium equation of F_A=F_B. F_A and F_B are the total interaction free energies per molar structural unit of major and minor components A and B in a copolymer, respectively. By using this equation, the conformation dependence of the intermolecular interaction free energy was investigated for the RIS model of methoxymethylated nylon-6 on the basis of the contour diagrams of conformational potential energy about backbone bonds.

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The relationship between the preparation conditions and the function of silk fibroin membrane was investigated in terms of water-sorption, membrane potential, ion permeability, X-ray diffraction and birefringence. We clarified the influences of preparation conditions of the silk fibroin membrane such as the concentration of fibroin solution (dilute and concentrated), substrate (acrylic resin and mercury) and drying rate (slow and rapid), on membrane potential and ion permeability of the fibroin membrane. The orientation function of the amorphous region is remarkably dependent on the preparation conditions, whereas that of crystal region is almost independent. When the mercury was used as a substrate and the drying rate is slow, the aggregation state of the fibroin membrane estimated from the iso-electric point, IEP was the highest. The membrane prepared from a concentrated solution on mercury at the slow-drying rate has the smallest average pore radius _??_. On the other hand, those for the membranes prepared from a dilute solution on an acrylic sheet are generally larger. It was clarified that the change of ion permeability of the membrane generally agreed to the order of IEP and _??_ of the membrane.

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Nickel salt of 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (MS-Ni) and its derivative (DS-Ni), benzophenone type UV absorber containing singlet oxygen quenching group, have been synthesized and its effects were examined on the photofading of some dyes in solution and on a solid with a UV irradiation. The rates of photofading of indigoid dye (C. I. Vat Blue 1), anthraquinonoid dye (C. I. Disperse Red 15) and azo dye (C. I. Acid Orange 20) were remarkably retarded in the presence of MS-Ni or DS-Ni not only in solution but also in a solid state, but that of Eosine (C. I. Acid Red 87) on a solid was suppressed scarcely. The effects of added Nickel p-toluenesulfonate and 2, 6-di-t-butylphenol on the photo-stability of dyes were also examined.

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The differences in clothing microclimates between the right and left half bodies have been studied for the subjects worn in the same or different material clothings on the respective side.
Shirts and trousers made of interlock fabric or tricot fabric were sewn, which could be divided into right and left half body pieces. Experiments were conducted for subjects in semi-nude or worn in variations of clothings under two conditions; one was that the subjects kept resting at an ambient temperature being kept constant and at the humidity being increased to a higher level for 50 minutes, and the other was that the subjects exercised for 10 minutes at a constant temperature and a constant humidity. Skin temperatures on six or twelve sites and temperatures and vapor pressures inside and outside the clothings at the back sites were recorded continuously. Oral temperature and weight loss were also measured. When subjects wore the same material clothings on the right and left halves, differences in clothing microclimates between the two halves were observed. These were inferred to reflect the states of the contact and air space between the skin and the clothing on each half body. The differences in heat and water transfers through the clothings between the right and left halves were found to be adequately estimated by a simultaneous comparison for a subject worn in clothings of different materials on each half body.

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Effect of load weight on the rub-fastness test has been investigated kinetically with standard cotton fabric samples stained with two kinds of iron oxide particles of different sizes. k₁, k_-1; and K, which were the rate constant of transfer of particles from adhered fabric to white cloth, the constant of the reverse process of k₁ and the equilibrium constant, respectively, were obtained. The values of k₁, k_-1 and K were empirically expressed as functions of the particle size and the load weight. Good agreements were confirmed between the experimentally observed amounts of removed particles and those calculated by the above relations.

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