Patent ID: 7932335

Claim:
A fluorine-containing elastomer having a copolymer composition, which comprises the following components: (a) 50-85 mol % of vinylidene fluoride, (b) 0-25 mol % of tetrafluoroethylene, (c) 7-20 mol % of perfluoro(methyl vinyl ether), (d) 2.5-15 mol % of CF 2 ═CFO(CF 2 CF(CF 3 )O) n CF 3 , where n is an integer of 2-6, (e) 0.5-1 mol % of CF 2 ═CFO(CF 2 CF(CF 3 )O) m CF 2 CF 3 where m is an integer of 2-6, and (f) 0.1-2 mol % of RfX where Rf is an unsaturated fluorohydrocarbon group having 2-8 carbon atoms, which can contain at least one ether bond, and X is bromine or iodine.