Dual-phase continuity and phase inversion in polycarbonate/polystyrene blends during compounding

The morphology of polycarbonate (PC) and polystyrene (PS) blends during compounding both in a twin-extruder and in an injection molding machine was studied. The validity of the theoretical model in prediction of the point of phase inversion were also investigated in the composition range. It was shown that the dual-phase continuity of PC/PS blends is strongly affected by blend composition and melt blending stage and usually obtained at the point of phase inversion. A semi-empirical expression for predicting the point of phase inversion based on torque ratio was also proposed.