Samples of carbon-fiber filled epoxy resin composites were moulded under centrifugal force. The gradient distribution of fiber content of samples was derived in direction of centrifugal force. Rectangular solid specimens were made from samples and surfaces of specimens were polished by sand papers. The electrical conductivity of specimens was measured by four-point probe method in both directions parallel to and parpendicular to the centrifugal force direction. The elastic modulus was derived from strain measurements during compression test in same directions as conductivity measurements. The correlation between conductivity and elastic modulus was found in both directions parallel to and parpendicular to the centrifugal force direction.

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The breaking processes of monofilaments of nylon6 and polyvinylidene fluoride were studied under elongation. The load was measured by a piezoelectric element and fracture surfaces were observed by an electron microscope. The breaking of nylon started from scratches on surfaces, and had three processes, i.e., a crack formation and a lowspeed growth, a high speed growth, the complex growth accompanied with other fractures. Each process had a cheracteristic fracture morphology and was partitioned by two border lines. The crack growth speeds of each process were 20, 41, 69m/s, respectively and the average was 33m/s. The heat by crack growth was culculated 150°C from the average speed and fracture surfaces were estimated to become 260°C . This temperature was consisted with the melted morphologies. The breaking of polyvinylidene fluoride started from inside and had three processes, i.e., the formation of a cohered molecular bundle and its cutting, a low speed growth, a high speed growth. The bundle was composed with molecular chains of 10⁸. The crack growth speeds were 22m/s at low, 36m/s at high and 29m/s at the avrage. Areas were partitioned by a border line and had different morphologies respectively.

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Thermoluminescence (TL), differential scanning calorimeter (DSC) and stress-strain (S-S) curve were studied for polypropylene (PP) fibers irradiated with ultraviolet (UV) rays.
As for the samples which were irradiated with UV rays for 2 to 8 hours, a TL peak was observed at about 110°C. By contrast, UV irradiation over 10 hours gave rise to an appearance of luminescence peak at around 160°C, which could be ascribed to the suitable crystals.
It seemed that the two types of PP crystal play an important role as a trap of the excited electron and released some of trapped electrons emitting thermoluminescence in the temperature range of crystalline dispersion and melting. Two endothermic peaks on DSC were observed. The intensity of the lower peak decreased with an increase of UV irradiation time, being correlated with the TL behavior.
The breaking point on S-S curve was shifted to the lower strain side by this UV irradiation almost along the curve of the unirradiated fiber, and reached the yielding point after UV irradiation for 8 hours.
TL was thus proved to be one of the useful techniques for investigation of UV degradation on fibers.

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Polymerization behavior of acrylonitrile (AN) and methylacrylate (MA) was investigated in homogeneous melt phase. It was found that homogeneous melted mixture of polyacrylonitrile, acrylonitrile, and water could be prepared through the polymerization of AN and MA in water (monomer/water=80/20) at conversion over 80%. Reactivity ratio of the polymerization showed that higher alternating tendency and closer composition with monomer mixture than those in bulk and dispersion polymerization.

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In this report, a measuring method of bobbin thread of lockstich sewing machine was proposed and an apparatus was constructed to confirm the utilities.
Relationships between the bobbin thread tension detected and the crank angle were investigated by the motion diagram.
The simplicity of the measurment of the bobbin thread tension makes possible the application of this method in simultanious measurment of the needle and the bobbin thread tension.

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Three kinds of azo dyes underwent rapid biodegradation under anaerobic condition. Aromatic amines were produced as the degradation products of azo dyes determined by HPLC analyses. The products were further degraded and 60% of the COD components could be mineralized under aerobic condition.

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In order to investigate the asymmetry in structure and properties of fabrics in the direction of the right and left 45° bias with respect to the warp, shingohsen twill weave and rayon plain weave were used. These two kinds of the bias samples for each fabrics were examined by the observation of scanning electron microscope photographs, microscope photographs, load-elongation curves and extension in length of circular flare skirts. The shape changes by extension, load-elongation curves and extension in length of circular flare skirts of two kinds of the bias samples were very different each other. These results show that the samples in the directions of the right and left 45° bias directions are asymmetrical with respect to the warp. The difference of two kinds of the bias samples for shingohsen and rayon materials both were seen due to the structure of the twist of the weaving threads and/or the textile weaves.

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