Heat-shrinkable polymer blends through interchain crosslinking based on ethylene propylene and chlorosulfonated polyethylene

The blending of hypalon (chlorosulfonated polyethylene [CSM]) with ethylene propylene (EP) in the presence of different grafting agents is expected to improve the interchain crosslinking between the non-functionalized EP and CSM phases. Five different grafting agents were chosen to introduce functional groups in the EP polymer. The reactive blending technique was used in the present work. The EP/CSM blending improves the shrinkability of the blends. The maximum extent of crosslinking is obtained in the presence of 4-4' diamine diphenyl methane while the minimum magnitude in found the presence of maleic anhydride. The interchain crosslinking phenomenon has been put forward through grafting, the extent of which depends on the grafting agent used. The results of the X-ray diffraction study are in good agreement with thermal analysis. (C) 2000 Elsevier Science B.V. All rights reserved.