| abstract |
A fluorine-containing elastomer capable of giving a vulcanized product with a good permanent set through peroxide vulcanization is produced by homopolymerization or copolymerization of a fluorine-containing olefin having 2 to 8 carbon atoms in the pressence of an iodine and bromine-containing compound represented by the general formula RBrn Im, where R represents a fluorohydrocarbon group, a chorofluorohydrocarbon group, a chlorohydrocarbon group or a hydrocarbon group, and n and m are integers of 1 and 2, and a small amount of 1,1-difluoro-2-bromoethylene. |