POLYMER BLENDS OF SEMIAROMATIC LIQUID-CRYSTAL POLYMERS WITH ENGINEERING PLASTICS

Polymer blends of semi-aromatic liquid crystal polymers (LCP) with engineering plastics such as poly-(butylene terephthalate), polycarbonate, polyarylate, nylon-6, and amorphous nylon were investigated. Flexural moduli of these engineering plastics were increased by blending with LCP. Flexural moduli of LCP/ester-type plastics were increased almost linearly with weight ratio of LCP; those of amide-type plastics were not so effectively increased, however, as those of ester-type plastics. This difference in the reinforcing effect can be related to the morphology of the blends. The amount of LCP dispersed into a ester-type polymer were found to be much larger than into an amide-type polymer. The result of DSC analysis, which shows an apparent decreasing in melting point of nylon-6, is also related to the fine dispersion of LCP into nylon-6. However, poor impact strengthes of every blend suggest that the interface adhesion between LCP and each engineering plastic is essentially poor.