The functionalization reaction of ethylene-propylene-diene monomer rubber (EPDM) and high-density polyethylene (HDPE) with maleic anhydride (MAH) during melt extruding through the high shear stress induced initiation by increasing the screw rotation speed of twin-screw extruder and changing the reaction temperature was investigated.With increasing the screw rotation speed

the scission of EPDM and HDPE molecule chains can be caused to form macroradicals and the reaction of EPDM/HDPE with MAH can be realized.The functionalized product (EPDM/HDPE)-g-MAH with higher percentage of grafting and better melt flow rate and lower gel content was prepared.The effects of (EPDM/HDPE)-g-MAH as a compatilizer on the compatibility

morphology and the mechanical properties of PA66/EPDM/HDPE blends were studied.The results showed that (EPDM/HDPE)-g-MAH greatly improved the compatibility of the blends.With an increase in (EPDM/HDPE)-g-MAH content in the blend

the size of minor component domains decreased greatly.And the Izod impact strength and elongation at break of the blends improved obviously.