Catalyst effect on the transesterification reactions between polycarbonate and polycaprolactone-B-polydimethylsiloxane triblock copolymers

Transesterification reactions between bisphenol-A polycarbonate and polydimethylsiloxane-polycaprolactone block copolymers were studied in melt at 270°C. Influence of the composition of reaction mixture and the catalyst type on the formation and properties of the products obtained were investigated by spectroscopic, chromatographic and thermal methods. Both of the catalysts used, zinc acetate and lanthanum acetylacetonate are very efficient transesterification catalysts for the system studied. GPC and DSC results clearly show the formation of novel polymers displaying combined properties of the polycarbonate and the silicone-ester copolymer.