Thermal and mechanical behavior of polycarbonate–poly(ethylene terephthalate) blends

Abstract

Melt blends of polycarbonate and poly(ethylene terephthalate) were formed by continuous extrusion and injection-molded into bars for mechanical testing. Thermal analysis was used to ascertain transitional behavior and the level of PET crystallinity at various points in the fabrication and testing process. The mechanical properties showed little departure from additivity except for the percent elongation at break which was substantially larger for certain blends than expected. Glass transition behavior suggests two amorphous phases for PC rich mixtures and only one mixed phase in the PET rich region. Crystallizability of the PET after the blend was held for prolonged times in the melt state suggests that interchange reactions do not occur to any great extent.