Melt rheology of polyarylate/polybutylene terephthalate blends

Abstract

Abstract The viscosity, the activation energy of flow, and the exchange reactions of bisphenol A 50/50 isophthalic/terephthalic acid and poly(butylene terephthalate) blends are studied by means of an extrusion capillary rheometer, covering a range of 10 s −1 to 300 s −1 shear rate and 280°C to 300°C temperature. The results are interpreted in terms of compatibility and free volume additivity. The decrease in viscosity with time is explained as a result of transesterification rather than degradation.