TIRE CURING BLADDER WITH IMPROVED RELEASE FROM THE TIRE INNERLINER

摘要

Disclosed are expandable bladders for use in curing presses for hydrocarbon rubbers such as pneumatic tires. The bladders are a crosslink elastomer comprising isobutylene repeat units and the bladder composition includes graphite. A preferred isobutylene elastomer is a brominated copolymer of isobutylene and pmethylstyrene. The bladders have enhanced lubricity, low adhesion to tire innerliners, and lower hot tension set. The above enhancements allow hydrocarbon rubbers such as tires to be molded with fewer defects caused by abraded or deformed bladders. They also enhance the useful life of the bladder reducing the cost of tire curing.