STEADY-STATE RHEOLOGICAL BEHAVIOUR AND MORPHOLOGY OF POLY(ETHYLENE TEREPHTHALATE)/LIQUID CRYSTALLINE POLYMER BLENDS

摘要

The theological behaviour of injection molded blends of polyethylene terephthalate , PET, with a liquid crystalline polymer, LCP, Vectra A950, from Hoechst, was analyzed using a controlled strain rheometer, ARES and a controlled tension rheometer, SR-200, both from Rheometrics, in a paralell plate geometry. Also capillar rheometry was used. PET/LCP blends in a weight percent ratio of 80/20, 60/40 40/60 and 20/80 were studied. It was observed that above 10 s~(-1), the addition of the LCP resulted in a decrease of the viscosity values. In all the blends, it was also observed an increase in the melt elasticity above 10 s~(-1). The dynamic rheological properties increased with the increase in LCP; up to the 60/40 ratio the creep recovery increased. The usual skin-core morphology was observed by scanning electron microscopy.