Titanium carbide (TiC) ⁄ acid-modified polypropylene (m-PP) composite is one of the candidate as the PTC resistor stable in relatively high temperatures, which is utilized for a self-recoverable element protecting from over currents in many kinds of electrical circuits. In the present study, the m-PP-based composites containing various volume fraction (φ₂) of TiC have been prepared; then, their viscoelastic characteristics were investigated in comparison with their electric conductivity as a function of temperature. Melting behaviors of the samples were also examined and discussed in terms of their morphological features. Alternatively, the changes in the storage moduli at room temperature with various φ₂ values of the samples could be expressed by a modified Kerner equation with the maximum φ₂ value of 0.69. When the value of φ₂ exceeded up to be 0.36, the resistivities of the sample decreased steeply with increasing φ₂ values. The filling structure of TiC⁄m-PP Composites is expected to be in random packing systems.

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The purpose of this paper is to compare different approaches toward the prediction of human psychological perception of clothing comfort performance from fabric physical properties. A series of running wear trial, which involved 8 sets of tight-fit garment and 38 subjects, was conducted in an environmentally controlled chamber. Thirty-three fabric physical property indexes were measured and 9 individual sensations (clammy, sticky, breathable, damp, heavy, prickly, scratchy, tight and cool) and overall comfort were rated by the subjects during the running period. Different predictive models were derived on the basis of human perception process to predict clothing comfort from fabric physical properties. Results show that hybrid models consist of data reduction (abstract fabric properties and sensations into physical and sensory factors respectively), self-learning capability (to learning the behaviour of individuals) and fuzzy reasoning (handle the fuzziness between sensory factors and overall clothing comfort) able to generate better predicted clothing comfort score than other predictive models in this study The correlation between predicted and actual clothing comfort rating was 0.739, with significant level of 0.001.

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The effects of washing on color were quantitatively examined using a colorimeter to elucidate subtle color difference between cotton cloth samples dyed with natural indigo and synthetic indigo. Color produced by reactive dye and indigo was also compared and the results were analyzed by a CIELAB color system. Color unevenness was subjectively evaluated by seven professional indigo dyers. With repeated washing, L^* value in cloth dyed with natural indigo increased at a lower rate than in cloth dyed with synthetic indigo. Color unevenness is related to dye absorption and dye aggregation.

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Native and regenerated cellulosic fabrics such as cotton, cupro, polynosic, viscose rayon taffeta and viscose rayon muslin were treated with ammonia-gas under various conditions. The dyeing and KES (Kawabata Evaluation System) mechanical properties were obtained. Although X-ray diffraction intensity profiles of the cotton showed almost no change by the treatment for 10 min, the peaks assigned to cellulose I decreased in intensity by the treatment for 60 min, and new peak intensity maxima assigned to cellulose III_I appeared at scattering angles of 2θ = 11.6° and 21.0°. On the other hand, the profiles of the regenerated cellulosic fabrics were not changed at all by the ammonia-gas treatment. Apparent dyeing rate of the cotton decreased regardless of the treating conditions, whereas the dyeing rate of the regenerated fabrics was unchanged by the treatment. KES shearing and bending properties (the moduli G and B; the hysteresis widths 2HG, 2HG5 and 2HB) in relation to the fabric hand decreased. Therefore, it is clear that the ammonia-gas treatment is effective to improve the soft hand of the cellulosic fabrics, especially for the regenerated cellulosic fabrics.

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Melting behavior of hydrogels of syndiotacticity-rich PVA derived from poly(vinyl pivalate) was investigated. One point six gram per deciliter aqueous solution of PVA with diad-syndotacticity of 61.2% (s-PVA(L)) turned to a gel when left standing at 2°C. Hydrogel made from 6 g⁄dl s-PVA(L) solution showed the melting temperature of 90°C. Melting temperatures of hydrogels of PVA with diad-syndotacticity of 68.7% (hs-PVA(L)) were above 100°C. The apparent enthalpy of fusion of a junction point in s-PVA(L) hydrogel was estimated to be 102 kJ⁄mol and this value was 2.6 times that of atactic PVA derived from poly(vinyl acetate).

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1,3,5,7-Tetraoxacyclononan (TOCN) was crystallized by cooling down to -20°C and then examined by transmission electron microscopy (TEM) at about -70°C with a cryo-transfer specimen holder. Long rodlike crystals and short lath-like ones of TOCN were recognized, and most of the rodlike ones were too thick for TEM observation. Some of fine tips of the rodlike crystals and most of the lath-like ones were, however, thin enough to take their selected-area electron diffraction patterns which showed that each of the crystals is highly crystalline like a single crystal (or like a twin crystal whose twin plane is parallel to the long axis of the crystal). Together with these rodlike and lath-like crystals, ill-formed crystalline aggregates of TOCN were also recognized.

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A novel biodegradable film was developed using paramylon from Euglena gracilis and its physical properties were investigated. Formic acid was suitable for the preparation of a solution of paramylon, and the film was prepared by casting the solution on a glass plate and drying the cast film in air without using coagulation bath. The film was strengthened through a hot steam treatment at 135°C for 2h. The strength and elastic modulus for the steam-treated film were 49.9 MPa and 1.99 GPa, respectively.

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