Abstract: Maleic anhydride, styrene (St), dicumyl peroxide (DCP), waste rubber powder (WRP) and polypropylene (PP) were mixed evenly in high-speed mixer and then compatibilized by in-situ reaction in a twin screw extruder. Influences of contents of MAH/St/DCP on mechanical properties were discussed in detail. The analysis of FTIR showed that MAH and St were successfully grafted with PP. The effects of one-step reaction compatibilization on the microstructure and phase interfaces were analyzed based on the scanning electron microscope (SEM) of the sections. The results showed that the increase in notch impact strength and tensile strength values were due to the improved interface by one-step reaction compatibilization, and the optimized ratio of PP/WRP/DCP/MAH/St (70/30/0.1/1.5/1.5).

Key words: polypropylene, waste rubber powder, one-step method, reactive extrusion, compatibilizer