Compositions vulcanisables à base de polymère ou copolymère d'oléfine et articles vulcanisés obtenus à partir de ces compositions

Vulcanizable compositions comprise an elastomeric copolymer of ethylene, another alphaolefin and optionally a cyclic or acyclic non-conjugated polyene, a reinforcing filler, a free radical acceptor and a peroxy ether of formula where n is 0 or 1, R1, R2 and R3 are C1- 10 saturated or aromatic hydrocarbon groups or halogen substitution products thereof, R1 being alternatively hydrogen, and R1 is a C1- 10 hydrocarbon group or a further ether or peroxyether group, optionally halogen substituted; or modifications thereof in which R1 and R2 are joined to form a cycloalkyl group or R2 is replaced by where R4 is a C1- 10 alkyl or t.-alkylaryl group and R11 is a C1- 10 saturated, unsaturated or aromatic group. The polymers may be derived from ethylene, propylene or butene-1 and optionally cyclooctadiene - 1,5, cyclooctadiene - 1,4, cyclododecadiene - 1,6, cyclododecadiene - 1,7, cyclododecatriene - 1,5,9, cycloheptadiene - 1,6, norbornadiene, methylene norbornene, hexadiene-1,5, 2 - methylpentadiene - 1,4, 5 - methyltetrahydroindene or dicyclopentadiene. Specified free radical acceptors are sulphur, quinonic and vinyl compounds, unsaturated polymers, dimaleimides and furfural and derivatives thereof. Many suitable peroxy ethers are specified and examples describe compositions comprising ethylene/propylene copolymers, sulphur or 1,3-difurfurylidene acetone, carbon black, zinc oxide, kaolin and 1-t.-butylperoxy-1-t.-butoxyethane, 2 - t. - butylperoxy - 2 - t. - butoxypropane, 1 - t. - butoxy - 1 - cumyl peroxide, a ,a 1 - di - (1 - t. - butoxy - ethylperoxy) - 1,4-diisopropylbenzene, 2 - ethoxy - 2 - t. - butylperoxypropane, a - methoxy - a - t. - butylperoxy - ethylbenzene, a - methoxy - a - cumylperoxy - ethylbenzene, a - isobutoxy - a - t.-butylperoxy - ethylbenzene, di - (1,11 - diphenyl-1,11 - diisobutoxy) - ethylperoxide, 2 - t. - butylperoxy - 2 - isopropoxypropane, 1,4 - di - [di-(2,21 - diethoxy) isopropylperoxy) isopropyl] benzene and a ,a 1-dimethoxy-a ,a 1-di-t. -butylperoxy-p-diethylbenzene.ALSO:2 - t - Butylperoxy - 2 - t - butoxypropane may be prepared by reacting t-butyl isopropyl ether with t-butyl hydroperoxide in the presence of cobalt acetate as catalyst.