Disclosed is a method for polymerizing, in an aqueous medium, at least one fluorinated monomer in the presence of a non-copolymerizable, non-fluorinated surfactant. The surfactant is generally selected from a non-ionic surfactant, a primary anionic surfactant, or a combination thereof. Fluorinated surfactants are not utilized. The resulting partially fluorinated polymer in the aqueous medium is either a semi-crystalline polymer or a crystalline polymer.