REACTIVE COMPATIBILIZATION OF PET LCP BLENDS BY A MULTIFUNCTIONAL EPOXY COUPLER/

A commercially available tetra-functional epoxy monomer has demonstrat ed to be a highly efficient reactive compatibilizer in compatibilizing the immiscible and incompatible polymer blends of poly(ethylene terep hthalate) (PET) and liquid crystalline polymer (LCP). This multi-funct ional epoxy monomer is able to react with both base polymers simultane ously as a coupling agent to form the desirable epoxy-co-PET-co-LCP mi xed copolymer. This mixed copolymer possessing segments of PET and LCP tends to reside at the interface to reduce the interfacial tension in the melt and the size of the resultant phase domains. Additionally, t he presence of this epoxy compatibilizer enhances the formation of gre ater numbers and finer dimension of the in situ-formed LCP fibrils. It requires only a very small amount of the epoxy monomer, a few fractio ns of one percent, to improve drastically the mechanical properties of the PET/LCP blends. The compatibilization mechanism by this multi-fun ctional epoxy monomer acting as a coupling agent has been discussed in detail. (C) 1997 Elsevier Science Ltd.