RADIATION-INDUCED GRAFTING OF VINYL MONOMERS ONTO POLYMER BLENDS .1. EFFECT OF VULCANIZING SYSTEMS ON THE GRAFTING OF ACRYLONITRILE ONTO EPDM PE BLENDS/

Ethylene propylene diene terpolymer (EPDM) was blended with high-densi ty polyethylene (HDPE) in the ratio 1:1. The blends obtained were vulc anized with sulfur or with peroxide vulcanizing systems. The vulcanize d samples were subjected to radiation graft copolymerization with acry lonitrile (AN). The parameters affecting graft yield, such as irradiat ion dose, monomer concentration, and type of solvent, were investigate d. It was found that sulfur-vulcanized blends are less susceptible tow ards graft copolymerization than peroxide-vulcanized blend even after purification from residual additives. Thus, the maximum graft yield wa s found to achieve 5% and 45% for sulfur- and peroxide-vulcanized samp les, respectively. In addition, the graft copolymerization of AN onto EPDM/PE blend improves its solvent resistance depending on graft yield , exceeding 8%. Also, the mechanical properties of the blends obtained were improved markedly at low graft percentages not exceeding 14%.