Patent ID: 7728087

Claim:
A method comprising polymerizing in an aqueous medium at least one fluorinated monomer in the presence of a non-copolymerizable, non-fluorinated surfactant, the surfactant selected from: (i) a non-ionic surfactant selected from, polyoxyethylene mercaptans, polyoxyethylene alkylamides, polyoxyethylene alkalamides, polyalkylene oxide block copolymers, fatty alkanol amides, amine oxides, sulfoxides, phosphine oxides, acetylenic glycols, and combinations thereof, or (ii) a non-ionic surfactant selected from polyoxyethylene mercaptans, polyoxyethylene alkylamides, polyoxyethylene alkalamides, polyalkylene oxide block copolymers, fatty alkanol amides, amine oxides, sulfoxides, phosphine oxides, acetylenic glycols, and combinations thereof, and a surfactant according to the formulas R1-CH 2 -L − M + , R1-CH—(R2L − M + )-R3-CH—(R4L − M + )-R5 or M +− L-CH 2 —R1-CH 2 -L − M +− ; wherein R1 to R5 can be an aromatic, alkyl, or alkenyl group, L is one of —COO − , PO 3 − , —OPO 3 − , —SO 3 − , or —OSO 3 − , and M + is a monovalent cation; and wherein the polymerization is carried out in the absence of a fluorinated surfactant and the resulting polymer is a partially fluorinated polymer having a semicrystalline or crystalline structure.