| 摘要 |
PURPOSE:A rubber composition containing halogenated butyl rubber is heat treated at high temperature before valcanization to reduce the rolling resistance and heat generation without any adverse effects on the wearing resistance, wet brake performance, tensile strength of its valcanized products and good processability while unvulcanized. CONSTITUTION:A rubber composition composed of a starting rubber containing more than 5wt% isobutylene-isoprene copolymer containing chlorine or bromine and of additives other than a vulcanization accelerator and sulur is heat treated at 180-220 deg.C and combined with a vulcanization accelerator and sulfur. The starting rubber composition preferably contains 5-30wt% chlorine or bromine- containing isobutylene-isoprene copolymer rubber, 40-95wt% natural rubber or polyisoprene rubber and less than 50wt% polybutadiene rubber. Further, a process oil containing more than 40% paraffin is preferably added by 5pts.wt. per 100pts. of the starting rubber to improve its processability. |
