BLENDS OF POLY(ETHER ETHER KETONE) WITH A THERMOTROPIC LIQUID-CRYSTALLINE POLYESTER .1. THE MORPHOLOGY, CRYSTALLIZATION, AND MELTING BEHAVIOR

Blends of poly(ether ether ketone) (PEEK) with a thermotropic liquid crystal copolyester (LCP-111), obtained by solution precipitation, were investigated by optical microscopy and differential scanning calorimetry. The as-precipitated blends underwent phase segregation on heating, as being evident by the microscopy observation. The phase morphologies, melting and crystallization behaviors of the blends were found to be affected by the LCP composition, showing smaller crystal size, slight depression of T(m) and higher degree of crystallinity with increasing LCP content. When isothermally crystallized from the melt, a maximum overall rate of crystallization was found for the blend containing about 20 wt% of LCP. The results were discussed in terms of competition between the nucleation and dilution effects of LCP on the crystallization of PEEK.