| abstract |
Curing systems for fluoroelastomers curable by peroxidic route which comprise bromine, optionally iodine, the bromine always being higher than iodine, comprising as essential elements:n (I) a curing agent comprising a bis-olefin having general formula:n wherein:n R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , equal to or different from each other, are H or alkyl C 1 -C 5 ; Z is a linear or branched alkylenic or cycloalkylenic radical C 1 -C 18 , optionally containing oxygen atoms, or a (per)fluoropolyoxyalkylenic radical. (II) a metallorganic hydride of formula:n wherein: M is selected from Sn, Si, Ge, Pb; x is an integer from 1 to 3; y, z are zero or integers from 1 to 3, with the proviso y + z = 4 - x ; w is an integer from 1 to 3; the R groups, equal to or different from each other, are selected from: alkyls C 1 -C 4 , aryls C 6 -C 12 , arylalkyls and alkylaryls C 7 -C 14 , optionally containing nitrile and/or hydroxyl groups. |