ADDITIVE EFFECTS ON THERMOTROPIC LIQUID-CRYSTAL POLYMER ALLOYS .1. EFFECTS OF 3RD COMPONENT OF THERMOTROPIC LIQUID-CRYSTAL POLYMER ON MECHANICAL-PROPERTIES OF VECTRA-A-REINFORCED POLYCARBONATE

The effects of addition of the 3rd component of thermotropic liquid cr ystal polymer (TLCP) on the mechanical properties and structure of Vec tra A-reinforced polycarbonate (PC) were studied. The 3rd TLCP was the copolymer of p-hydroxybenzoate (PHB) and ethyleneterephthalate, known as X-7G TLCP. PC, Vectra A, and a small amount of the 3rd TLCP were b lended in the molten state, the extrudate of which was cut and injecti on-molded. The mechanical properties of the blends were improved drama tically by addition of a small amount of the 3rd TLCP component. SEM r evealed that the blend systems were always phase-separated, even after injection-molded, and the fibrils of Vectra A in the injection-molded blends became finer and longer in the presence of the 3rd TLCP.FT-IR indicated that no special chemical reaction took place between the TLC P and PC. The dynamic viscoelastic analysis indicated that the additio n of the 3rd TLCP component had almost no effect on the thermal endura nce of the blends. X-Ray diffraction analysis showed that the orientat ion of Vectra A fibril in the blend became higher when the 3rd TLCP wa s added, which led to the great improvement of the mechanical properti es. Based on the assumption of additivity law, the fibril modulus was evaluated and found to be in the same order as the orientation evaluat ion by X-ray diffraction. The thinning of fibrils by addition of the 3 rd TLCP component was discussed based on the crystallization kinetics of rodlike molecules.