Molten bisphenol‐A polycarbonate‐poly(ethylene terephthalate) blends. I. Identification of the reactions

This paper is devoted to the study of the reactions taking place in molten bisphenol‐A polycarbonate‐poly(ethylene terephthalate) mixtures. The analysis of the reaction products by infrared, proton and nuclear magnetic resonance spectroscopy, and by thermogravimetric analysis shows that the main reaction is an exchange reaction identical to that occurring in bisphenol‐A polycarbonate‐poly(butylene terephthalate) mixtures. However, some other reactions consecutive to this exchange reaction also take place, probably resulting from the instability of the ethylene carbonates produced by transesterification.