Abstract
Blends of poly(butylene terephthalate) (PBT) and thermotropic liquid crystalline polymer (LCP) containing 60 mol% p-hydroxybenzoic acid and 40 mol% poly(ethylene terephthalate) were investigated in terms of mechanical, morphological and rheological properties. Mechanical property of PBT/LCP blends was affected by their compositions and fibril formations. Tensile and impact strengths of the PBT/LCP (95/5) blend were one and half times higher than those of PBT itself. Improvement of mechanical properties was obtained by LCP reinforcing effect in the PBT matrix with excellent dispersity and with partial miscibility between PBT/LCP as observed by Scanning Electron Microscope (SEM). Fracture surface of the injection molded samples showed that the LCP formed finely dispersed spherical domains in the PBT matrix, and the LCP domains were the larger spherical droplet with increasing LCP content. However, PBT/LCP (95/5) blend showed tHe smallest LCP droplets in the whole compositions. Addition of 5~10 wt% of LCP slightly increased the melt viscosity of PBT/LCP blends. However, above 10 wt% of LCP content effectively affected a reducing melt viscosity of the PBT/LCP blends, and sharp shear thinning was shown at high shear rate.
