Brominated unsaturated ether cure site monomers useful in the invention include ethers such as 2-bromo-perfluoroethyl perfluorovinyl ether and fluorinated compounds of the class CF2Br???Rf???O???CF???CF2(Rf is perfluoroalkylene), such as CF2BrCF2O???CF???CF2, and fluorovinyl ethers of the class ROCF???CFBr or ROCBr???CF2, where R is a lower alkyl group or fluoroalkyl group, such as CH3OCF???CFBr o