FLUORORUBBER COPOLYMER EXCELLENT IN LOW-TEMPERATURE PROPERTY AND CURING COMPOSITION THEREFOR

摘要

PURPOSE: To economically obtain a fluororubber copolymer having excellent vulcanizability and good low-temperature resistance by copolymerizing vinylidene fluoride, perfluoro(methyl vinyl ether), hexafluoropropylene and tetrafluoroethylene in the presence of a specified diiodo compound. ;CONSTITUTION: The copolymer is obtained by radical polymerization in the presence of a diiodo compound represented by the formula RI₂ (wherein R is a 1-16C saturated fluorohydrocarbon group or chlorohydrocarbon group, or a 1-3C hydrocarbon group) and contains 65-85mol% vinylidene fluoride units, 3-20mol% perfluoro(methyl vinyl ether) units, 3-25mol% hexafluoropropylene units and 3-25mol% tetrafluoroethylene units. The iodine atoms introduced into the copolymer from the diiodo compound account for 0.01-1wt.% of the total weight of the copolymer, and the copolymer has a Mooney viscosity [ML₁₊₁₀(100°C)] of 20 to 150.;COPYRIGHT: (C)1996,JPO