The main varieties of impact modifier include chlorinated polyethylene (CPE), methyl methacrylate butadiene styrene copolymer (MBS), acrylonitrile butadiene styrene copolymer (ABS), EVA, ACR, acrylonitrile butadiene random copolymer (NBR) and rigid particles. The mechanical properties of impact modifier are better than that of low-density polyethylene, and its melting point is higher than that of low-density polyethylene, about 126 136 ℃. Its embrittlement is mainly used as a modifier of PVC to improve the impact resistance of PVC.