Two kinds of rigid polymers, poly (p-phenylene benzobisthiazole), P (PBZT), and poly (4, 4' biphenylene benzobisthiazole), P (BPBZT), and its blend were crystallized isothermally from 0.1 wt% concentrated sulfuric acid solution. The precipitates of pure polymers were unhulled-rice-like discs which were chained to form a straight rod or a rosary. Molecules were oriented normal to the long axis of rod. As structural similarities of P (PBZT) and P (BPBZT), such as a rigid structure, morphology and existence of the axial shift in the crystalline state, the formation of mixed crystals was expected in the precipitate of P (PBZT) / P (BPBZT) blend. Under the condition that the cloud temperatures of both polymers were closed to each other and the crystal growth rates of both polymers were almost the same, the precipitates of blend sample showed a lath-shaped morphology, which differed from either precipitate of pure polymers. Crystalline order of P (BPBZT) component in the precipitates of blend sample was low as same as the precipitate of pure P (BPBZT). The annealing temperature, at which crystallinity of P (BPBZT) component began to increase, was about 100°C higher than that for pure P(BPBZT) precipitate. In addition to crystallites of P (PBZT) and P (BPBZT), a mixed crystal or an ordered state of mixed molecules of both polymers coexisted in the boundary region of both crystallites.

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The structure development of poly(phenylene sulfide) (PPS) and poly(ethylene terephthalate) (PET) films in successive-biaxial drawing process was studied through the analysis of the structural change of films with thermal shrinkage. When the first and second step draw ratios were equal, molecular chains showed preferential orientaion along the second step draw direction. After the thermal shrinkage of the equal-biaxial drawn samples with the draw ratios of 2.0 for PPS and 4.0 for PET, the directions of crystal orientation (c-axis orientation for PPS and a^*-axis orientation for PET) changed from the second step draw direction to the first step draw direction. Both polymer films with lower draw ratios became almost isotropic, whereas the crystal orientation directions of the higher draw ratio films (c-axis orientation for both samples) remained intact with the thermal shrinkage. Accordingly it was speculated that these par-ticular draw ratios for both polymers correspond to the boundary between the formation of the oriented crystalline embryo and the completion of the fiber structure formation. In other words, the crystalline embryos can rotate during the second step drawing and the thermal shrinkage process, while the crystals cannot rotate anymore after the fiber structure was completely developed.

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Molecular orientation mechanism in fiber drawing process was discussed with the measurement results of birefringence and thermal shrinkage for unoriented amorphous poly (phenylene sulfide) (PPS) fiber. The drawing conditions were as follows; drawing temperature 90-110°C, drawing rate 0.005-0.040/s, draw ratio 1-4. Drawability of PPS fiber showed a sharp increase above 90°C, and also showed ‘super-draw’ phenomenon at 110°C. Strain induced crystallites which can be observed with X-ray diffraction were formed in the samples whose birefringence exceeded about 0.10, while the samples whose birefringence were within 0.06 to 0.10 contained oriented crystalline embryo because they indicated self-elongation and orientation increase in the thermal shrinkage process. The apparent relaxation times estimated with assuming upper-convected Maxwell model showed temperature dependence whose activation energy corresponded 50 to 80kJ/mol, and also showed obvious draw rate dependence and draw ratio dependence. Mechanical properties of drawn fibers at room temperature showed good relationships with the birefringences.

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Dispersion behavior has been characterized by acoustic microscopy method for polypropylene (PP) filled with calcium carbonate (CaCO₃). The heterogeneous structure of the large size such as aggregate, agglomerate of the filled particles and presumably void at polymer-particle interface possessing modulus heterogeneity in the compounds were evaluated. Binarization method was carried out in order to obtain area fraction of the structure. The relationship between dispersion behavior and content, size and surface treatment of the filler, and the mechanical property (elongation at break) has been investigated. The heterogeneous structure was inclined to increase with the increase in CaCO₃ content and the decrease in CaCO₃ particle size. The heterogeneous structure in composites filled with CaCO₃ of various particle sizes markedly decreased by the surface treatment of CaCO₃. While, the elongation at break of PP/CaCO₃ composites could roughly be expressed as a function of aggregation or agglomeration fraction calculated from ultra-sonic image.

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The equilibrium surface tension of the aqueous solutions of benzyl alcohol (BA) -C. I. Basic Yellow 11 (BY11) mixture and m-cresol (CR)-BY11 mixture was measured as a function of the total molarity (_??_) and the mole fraction of dye (_??_₂). By applying Matomura's thermodynamic equation, the mole fraction of dye in the adsorbed film (_??_^H₂) was estimated. The phase diagram of BA-BY11 system, which represents the relationship between _??_₂ and _??_^H₂, became a deformed semilunar type, and in comparison with the aqueous solution the adsorbed film abounded in the more surface-active BY11 molecules over the whole _??_₂ range. The phase diagram of CR-BY11 system having a minimum point was analoguous to that of an azeotropic mixture. It was concluded that the adsorbed film of CR-BY11 system abounds in the less surface-active CR molecules, and in the more surface-active BY11 molecules at the higher and the lower _??_₂ region than that at minimum point respectively. The _??_₂ value corresponding to the minimum point decreased along with the lowering of the surface tension. This adsorption behavior differed remakably from that of BA-BY11 system. It can be explained by the strong interaction between CR and BY11 molecules in the adsorbed film due to the phenolic hydroxy group of CR molecule.

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The mechanism of improvement in exhaustion and fixation of acid dyes in the recently reported low-temperature dyeing of silk fabrics with acid dyes in the presence of a hydrogen peroxide/glucose redox system was studied. The increases in dyeing rate and adsorption of acid dyes on silk fibers in the presence of the redox system could be attributed to the decrease in pH due to the decomposition of glucose with hydrogen peroxide but not to the covalent fixation of dyes on silk assisted by the free radicals.

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A comparative analysis is presented on the three conventional methods and our new one for evaluating the basic thermal insulation of cloting. A thermal manikin regulated at constant temperature over all parts was seated on a chair and, in the steady state, the environmental temperature, the amount of heat which the manikin lost, and the local skin temperature at nineteen points were measured for various clothing ensembles covering the body. From the data obtained were estimated the thermal insulation only by the skin when the manikin was unclothed and that by the total when clothed; based on these the basic thermal insulation of each clothing was evaluated by the current methods as well as ours and the results were compared. An investigation also on the role of the insulation by the outer clothing surface revealed that, if it was neglected, greater errors might be caused in estimating the basic thermal insulation of clothing.

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Cotton fabrics were wash and wear finished with a loop transfer applicator, one of low wet pick-up finishing apparatus. A resin solution was applied evenly to the fabrics at a low pick-up, where no resin migration occurred on drying, so that the reduction of strength might be lessened and the durable press properties and the wrinkle recovery might be enhanced. As a crosslinking agent, dimethyloldihydroxy-ethyleneurea, and as acidic catalyst, MgCl₂•6H₂O and glycolic acid were used and the add-on (pick-up) of the resin solution was adjusted to about 30%. In comparison to the ordinary finishing, the reduction of the strength in tensile and tearing in the low wet pick-up finishing was lower for any of the finished fabrics, at the same level of the durable press properties. The pretreatment with thermoplastic resins prevented the reduction of the tensile strength.

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