Studies on polycarbonate/polystyrene/polycarbonate-g-polystyrene blends. III. Optical properties of PC/PS/PC-g-PS blends

Polycarbonate (PC)/polystyrene (PS) blend is a typical immiscible system. It is, however, still transparent. In this paper, this irregular phenomenon is clarified experimentally and theoretically. A new method of obtaining birefringence-free polymers without sacrificing orientation in materials is proposed. This involves combining suitable amounts of PC and PS in the form of a blend. The observed drastic reduction in birefringence is the result of the compensation of positive and negative contributions to the overall birefringence. ©1997 SCI