Perfluoroelastomer composition

摘要

There is provided a perfluoroelastomer composition having a low glass transition temperature and excellent cold resistance and heat resistance and comprising a perfluoroelastomer comprising a tetrafluoroethylene unit (a), a perfluoro vinyl ether unit (b) and a cure site unit (c) having nitrile group, carboxyl group and/or alkoxycarbonyl group as a cure site, wherein the perfluoro vinyl ether unit (b) is contained in an amount of 8 to 23% by mole in the perfluoroelastomer.

主权项

1. A perfluoroelastomer composition comprising a perfluoroelastomer comprising:
(a) a tetrafluoroethylene unit, (b) a perfluoro vinyl ether unit represented by the formula (I): wherein Rf is a linear or branched perfluoroalkylene group having 1 to 6 carbon atoms; “n” is an integer of 2 to 20, and when “n” is 2 or more, Rfs in “n” (RfO) units may be the same or different; Rf′ is a linear or branched perfluoroalkyl group having 1 to 6 carbon atoms, and (c) a cure site unit having a nitrile group, a carboxyl group and/or an alkoxycarbonyl group as a cure site, said perfluoro vinyl ether unit (b) being contained in an amount of 13 to 23% by mole in the perfluoroelastomer, wherein a glass transition temperature of the perfluoroelastomer is −70° C. to −10° C., and wherein a temperature of the perfluoroelastomer measured with a thermogravimetric/differential thermal analyzer at 20% mass reduction is not less than 445° C.