BLENDS OF A LIQUID-CRYSTALLINE POLYMER WITH POLYETHER ETHER KETONE

Blends of Polyether ether ketone (PEEK) and a thermotropic liquid crystalline Polymer (LCP) based on paraoxy-benzoyl and oxy-biphenylene terepthaloyl units were prepared using a static mixer attached to a single screw extruder at 420-degrees-C. Rheological studies indicated an increase in the viscosity of the blends upon the addition of LCP. Thermal studies on these blends demonstrated their poor thermal stability compared to the parent materials. The mechanical properties indicated improvement in Young's tensile and flexural modulus but no improvement in the break strength with the addition of the LCP. Morphological studies indicated the formation of ellipsoids of LCP at low LCP concentration in the matrix of PEEK, with extended ellipsoids being observable at 25 percent LCP composition. Phase inversion was noticeable at higher LCP content blends with the formation of PEEK fibrils in the matrix of the LCP. Dynamic studies on these blends showed an increase in the storage modulus with the addition of LCP.