Patent ID: 9221925
Filing Date: 2015-12-29
Classification: B29C,B29K,C08F,C08J

Abstract:
1. A process for making an expanded functional TFE copolymer material, said process comprising: a) emulsifying at least one functional comonomer having a functional group to form a functional comonomer emulsion comprising water and a fluorosurfactant to form a functional comonomer emulsion; b) providing at least a portion of the functional comonomer emulsion to a polymerization vessel; c) providing tetrafluoroethylene (TFE) monomer to the polymerization vessel; d) polymerizing TFE monomer and the at least one functional comonomer in an aqueous dispersion polymerization process; e)consuming the at least one functional comonomer in the polymerization or removing the at least one functional comonomer prior to completion of the polymerization; f) continuing polymerization of the TFE monomer after consuming or removing the at least one functional comonomer and in the absence of comonomer; g) collecting a dispersion of particles or fine powder of a functional TFE copolymer having pendant functional groups, h)coagulating the dispersion of particles or fine powder of the functional TFE copolymer to form coagulated particles or coagulated fine powder; i) washing and drying the coagulated particles or coagulated fine; and j) processing by paste extrusion and subsequently expanding into a porous polymeric material having a microstructure of nodes interconnected to fibrils.