Patent ID: 7408006

Claim:
A crosslinking system of perfuoroelastomers curable by peroxidic way, having an improved thermal resistance at high temperatures, higher than 300° C., up to 350° C., comprising: as crosslinking agent, a bis-olefin having general formula: wherein: R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , equal to or different from each other, are H or C 1 -C 5 alkyls; Z is a C 1 -C 18 linear or branched alkylene or cycloalkylene radical, optionally containing oxygen atoms, or a (per) fluoropolyoxy-alkylene radical; the amount of the bis-olefin, expressed in per cent by weight on the total polymer, being from 0.6% to 1.8%; peroxides for the peroxidic curing, capable to generate radicals by heating, in an amount from 0.2% to 1.3% by weight on the polymer.