A study on the reactive compatibilization of polyester (PBT)/ liquid crystalline polymer (LCP) blend: Catalyst effect

The in situ compatibilization of poly(butylene terephthalate) (PBT) with liquid crystalline polyester via catalyzed transesterification reaction was examined through thermal, rheological, morphological and mechanical studies. The addition of the catalyst, dibutyltin-dilaurate, was found to promote the transesterifications between PBT and LCP within a short reaction time. Produced copolymer acted on the interface to diminish the size of the dispersed phase (LCP), enhanced interfacial adhesion and caused an early increase of flexural strength. Depending on the amount of PET moiety in the LCP copolymer, physical properties showed different behaviour. Flexural strength was reduced after a long time reaction due to the chain scission. Transesterification confirmed by NMR spectroscopic analysis played a major role in the interchange process.