Compatibilization of poly(ethylene terephthalate)/liquid crystal polymer blends by means of bisphenol A polycarbonate

A compatibilization method that consists of the addition of minor amounts of a commercial thermoplastic, which interacts or reacts with both the matrix and the dispersed liquid crystalline polymer (LCP) of thermoplastic/LCP blends, has been tested in the case of poly(ethylene terephthalate)/Vectra A950 (PET/VA) blends by means of the addition of bisphenol A polycarbonate (PC). The smaller particle size, rougher surface of the fibers and higher ductility of the PET/VA blends with a 30% of the PET substituted by PC clearly showed the suitability of PC as a compatibilizer. The moduli of elasticity of the compatibilized and uncompatibilized blends were similar. This was due to the less-developed fibrillation of the compatibilized blends, a consequence of their smaller particle size and decreased matrix viscosity. These changes counteracted the effects of improved interfacial adhesion. The improved adhesion led to higher ductility and tensile and impact strengths in most of the compatibilized blends.