Patent ID: 8623963

Claim:
An emulsion mixture comprising: i) a first emulsion of a composition comprising a crosslinkable fluoroelastomer terpolymer consisting essentially of tetrafluoroethylene (TFE), perfluoroalkyl vinyl ether (PAVE), and perfluorocyano vinyl ether (CNVE) monomer units and that contains no additional crosslinking agent, coagent or catalyst, and ii) a second emulsion comprising a functionalized polytetrafluoroethylene (PTFE) polymer comprising 0.1 to 3 mol % perfluorocyano vinyl ether (CNVE), wherein the particle size of the functionalized PTFE polymer is about 10 nm to 100 nm, and wherein a composite comprising functionalized PTFE-crosslinkable fluoroelastomer terpolymer isolated from an emulsion mixture of said first and second emulsions contains less than 3000 ppb of metals and is crosslinked in the absence of a crosslinking agent, coagent or catalyst.