Patent ID: 8415418

Claim:
A heat-curing reactive composition based on natural and/or synthetic polymers containing olefinic double bonds, and vulcanizing agents, which composition contains a) at least one liquid cis-1,4-polyisoprene with a weight-average molecular weight of between 20000 and 70000 b) a vulcanization system c) at least one polybutadiene liquid at 22° C. wherein 60 to 90% of the double bonds take the form from cis-1,4 polymerization, wherein the liquid cis-1,4-polyisoprene a) constitutes a proportion of the entire composition in the range from 9 to 15 wt. %, the vulcanization system b) is selected from the group consisting of: b1) sulfur and one or more vulcanization accelerator(s), b2) peroxide or disulfide vulcanization systems b3) quinones, quinone dioximes or dinitrosobenzene, and the at least one polybutadiene c) liquid at 22° C. constitutes a proportion of the entire composition in the range from 16.8 to 29 wt. %.