THE NUCLEATING EFFECT OF A SEMIFLEXIBLE LIQULD-CRYSTALLINE POLYMER FOR THE CRYSTALLIZATION OF POLY(PHENYLENE SULFIDE)

Blends of poly(phenylene sulfide) and a semiflexible liquid-crystallin e polymer have been prepared, in the whole range of concentration, by melt mixing. The effect of the LCP phase on the crystallization of PPS has been studied by non-isothermal and isothermal calorimetry. It has been found that the addition of only 2-5% LCP into PPS strongly incre ases the crystallization rate of the latter polymer. This effect has b een interpreted as the result of an increased nucleation density. The morphology of the blends, studied by scanning electron microscopy, has shown that the two polymers are incompatible, although the phase disp ersion is good. Under elongational flow, the dispersed phase shows a d istinct tendency toward fibrillation.