Abstract: Effect of shear-tensile alternating flow field on the dispersive and distributive mixing performance of high viscosity ratio blend systems was studied using a series of PP/PE-HD blends with different viscosity ratio in a triangle arrayed three-screw extruder and a traditional twin-screw extruder. It showed that the three-screw extruder gave better dispersive and distributive mixing performance for high viscosity ratio composite systems than those of the twin-screw extruder, and the toughening effect was enhanced with increasing viscosity ratio of the blend systems.

Key words: three-screw extruder, twin-screw extruder, high viscosity ratio, alternating flow field, blending modification