LATEX COMPOSITION BASED ON POLYISOPRENE EPOXIDE

The present invention relates to a rubber composition which improves the compromise between stiffness in the cured state and the hysteresis of the composition. The rubber composition comprises from 0 to less than 20 phr of a butyl rubber, from more than 50 to 100 phr of a polyisoprene matrix, the polyisoprene matrix containing an epoxidized polyisoprene having a molar degree of epoxidation ranging from 5% to less than 50%, a carbon black and a silica, the weight of carbon black being greater than 50% of the total weight of carbon black and silica, from 0 to less than 2 phr of a coupling agent, and a crosslinking system. The epoxidized polyisoprene is an epoxidized natural rubber or an epoxidized synthetic polyisoprene having a molar content of 1,4-cis bonds of at least 90% before epoxidation, or a mixture thereof, and, if the epoxidized polyisoprene is an epoxidized polyisoprene having a molar degree of epoxidation of from 5% to 25%, the rubber composition contains more than 50 phr of epoxidized polyisoprene.