Patent ID: 7897682

Claim:
A process comprising polymerizing at least one fluorinated monomer in an aqueous polymerization medium comprising initiator and polymerization agent to form an aqueous dispersion of particles of fluoropolymer, said aqueous dispersion of particles of fluoropolymer formed by said process having a fluoropolymers solids content of at least about 10% by weight, said polymerization agent comprising fluoropolyether acid or salt thereof and hydrocarbon surfactant, said aqueous polymerization medium comprising less than about 300 ppm of perfluoroalkane carboxylic acid or salt fluorosurfactants, wherein said polymerization agent comprises a major amount by weight of fluoropolyether acid or salt thereof and a minor amount by weight of hydrocarbon surfactant and wherein said fluoropolyether acid or salt thereof is present in said aqueous polymerization medium in an amount of about 5 ppm to about 2000 ppm based on the weight of water in said aqueous polymerization medium.