The Effect of HVA-2 Addition on the Properties of PP–EPDM–NR Ternary Blends

Abstract

The effect of N, N′-m-phenylenebismaleimide (HVA-2) addition on the properties of polypropylene (PP)–ethylene–propylene diene terpolymer (EPDM)–natural rubber (NR) ternary blends is investigated in this study. The blends have been prepared in a laboratory internal mixer at 180 C and a rotor speed of 50 rpm. Process development, mechanical properties, and thermal and morphological studies are carried out for both PP–EPDM–NR blends with and without HVA-2. Results indicate that the torque values, the stabilization torque, tensile strength, and tensile modulus increased with the addition of HVA-2 in the blends, whereas elongation at break showed an opposite trend. The addition of HVA-2 reveals a tendency for the percentage of crystallinity ( Xc) to increase, but no significant evidence is observed in the thermogravimetric analysis. Scanning electron microscopy studies indicate that the formation of crosslinks in the rubber phases is responsible for the properties enhancement of PP–EPDM–NR blends with HVA-2.