Fracture studies of PP/PC/SEBS Ternary Blends: the effects of SEBS content

Polypropylene/Polycarbonate/Poly(styrene-b-(ethylene-co-butylene)-b-styrene) (PP/PC/SEBS) ternary blends were produced via melt blending in a co-rotating twin-screw extruder. The fracture behaviors of the blends,including single edge notched three point bending (SEN-3PB), were studied to establish the role of SEBS in improving the fracture toughness of blends. Our results showed that, addition of 20 wt% SEBS induces the great improvement of fracture energy and a brittle-ductile transition occurs in the SEBS concentration of 20 wt%. The great increase of fracture energy in R20 and R30 samples was due to great increase of crack propagation energy. In addition, it can be concluded that brittle-ductile transition is controlled by crack propagation process