Predicting the yield stress of polymer glasses directly from processing conditions: application to miscible systems

A previously developed model which predicts the yield stress of a polymer glass directly from processing conditions is applied to a system of miscible polymers. The selected system consists of a blend of polycarbonate with polyester and three blend compositions of increasing weight percentages polyester are investigated with respect to their aging kinetics. Based on these kinetics, the yield stress as it results form the thermal history experienced during processing is predicted and found to be in good agreement with experimental results. The parameters governing the evolution of the yield stress are shown to follow the rule of mixtures, enabling the prediction of the yield stress of any blend composition.