In order to improve the breaking strength and elongation of Polybutylene succinate (PBS) monofilament, the monofilament was produced by blending PBS and Polybutlyne adipate-co-terephthalate (PBAT). The PBS/PBAT blend monofilament was prepared by the melt spinning system, and the weight ratios of the compositions of PBS/PBAT was 100/0, 95/5, 90/10 and 85/15, respectively. The breaking strength, elongation, softness and crystallization of PBS/PBAT blend monofilament were analyzed by using a tensionmeter, softness measurement, X-ray diffractometer in the both dry and wet conditions. The PBS/PBAT blend monofilaments were spun in the take-up velocity of 1.19m/sec under the drawing ratio of 6.8:1 condition. The production volumes of PBS/PBAT blend monofilaments showed 20% less than that of Nylon. The breaking strength of PBS/PBAT blend monofilaments were decreased as PBAT contents increased, while elongation and softness were increased. In case of PBAT content were over 5%, the breaking strength, elongation and softness of PBS/PBAT blend monofilaments were not shown to increase in spite of increasing in PBAT contents. Based on these results, it was possible to make the monofilaments with the maximized physical properties when the PBAT contents at 5%.

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Several approaches have been suggested so far for the purpose of preparing thermoplastic prepregs: ( i ) the high shear rate, high-temperature method, based on the fact that the resin viscosity usually drops with increasing temperature and shear rate (shear thinning effect); (ii) the fiber-mixing method, ' where the impregnated strand is prepared by mixing the fiber-shaped resin and reinforcing fibers using a melt impregnation technique; (iii) the film method, according to which the fiber impregnation is made by heating two sheets of resin films containing the fiber bundles arranged between them; and (iv) the plasticizer addition method, * utilizing the phenomena that meltingpoint depression and viscosity reduction of the resin are caused by the addition of the diluents. However, all the methods mentioned above have respective disadvantages. For example, in the case of the plasticizer addition, the plasticizer must be removed in the after-treatment step of the prepreg manufacturing process, and for other methods, it is hard to achieve the complete wetting of fibers with molten resin because of the high viscosity of the resin? In particular, for the resin system whose melting point and thermal decomposition temperature do not differ so much, the lowering of melt viscosity by increasing temperature is hard to expect in view of thermal stability.T o overcome the deficiencies associated with resin viscosity, a new method has recently been p r~p o s e d ,~ where fiber bundles are covered with the dry powder of the impregnating resin and are passed through the heated nozzle to cause the melted resin to impregnate the fibers. But the application of this method is limited to the fiber-bundle system with relatively few filaments.Because of the above mentioned problems, we have developed a convenient method for preparing thermoplastic prepregs by means of the "solution-bond method," similar to the solution-microbond m e t h~d ,~ for preparing the pullout test specimen. According to this method, the impregnated strand, and, hence, the prepreg, may be produced by dissolving the thermoplastic polymer in an appropriate solvent, immerging the strand in resin solution, then evaporating the solvent by vacuum-drying, followed by reheating above the melting temperature of the resin polymer for removal of any residual solvent and for complete, uniform wetting of the fibers.T o test the validity of this method, the application to the glass fiber/high-density polyethylene (HDPE) system

We investigated the evolution of crystal formation as a function of drawing ratio in poly(1,4-diaminobutane-co-adipic acid-co-ε-caprolactam-co-diethylenetriamine)(nylon 466T) copolymer formed by four monomers, i.e 1,4-diaminobutane, adipic acid, ε-caprolactam, diethylenetriamine(DETA), using synchrotron X-ray scattering measurement. In case of pristine(as spun) nylon 466T fiber, it was consisted with unoriented nylon 6α and unoriented nylon 46αphases. As increase the drawing ratio, unoriented nylon 6α was transformed to oriented γ phase, while unoriented nylon 46αchanged to oriented 46 α phase. The effect of the addition of DETA was not observed in the pristine fibers.However, DETA affected to restrict the formation of crystals at the maximum drawing condition, and as a result it had a role to increase the moisture regain.

In order to study the crystal structures of Nylon 4 copolymer films by elevating temperature and shooting Xray along the three principal directions (through, edge, and end directions), HT (high temperature) WAXD (wide angle X-ray diffraction) was used. Three conclusions were derived from this work. First, the diffraction intensity of samples was strongest in the edge direction. Also, the diffraction intensity became stronger as the draw ratio increased. Second, the Brill transition appeared at 140 o C, which indicates that two peaks merged into one peak within the X-ray diffraction intensity graph. Finally, after cooling the specimen for 24 hours, the WAXD data returned to the same initial state.