FIBERS FROM POLYPROPYLENE AND LIQUID-CRYSTAL POLYMER BLENDS .3. A COMPARISON OF POLYBLEND FIBERS CONTAINING VECTRA-A900, VECTRA-B950 AND RODRUN-LC3000

Polyblend fibres were made of polypropylene (PP) and three thermotropi c liquid crystal polymers (LCPs). The LCPs were found to exist in diff erent morphological structures; the Vectra A900 and Vectra B950 LCPs e xisted mainly as fibrils, while the Rodrun LC3000 existed as short elo ngated ribbons. The tensile properties of the as-spun fibres were impr oved on addition of the LCPs, with the properties of the drawn polyble nd fibres varying with the drawing procedure. In one-stage drawing, th e polyblend fibres gave poorer tensile properties than the pure PP fib re. However in two-stage drawing, the Vectra A900 blend showed an incr ease in initial modulus over that of the pure PP fibre, while the Rodr un LC3000 blend produced an improvement in fibre tenacity.