The suspension-emulsion combined polymerization of fluorinated acrylic monomer and the fluorinated latex film surface properties

The perfluoroacrylate-containing copolymer composite particles were fabricated by suspension-emulsion combined polymerization (SECP). The features and formation mechanism of resulting polymer particles in SECP were studied. The fluorinated latexes with better stability and those fluorinated films with high surface fluorine content were prepared by SECP using fluorine-free surfactants as an emulsifying agent, and the surface natures of the fluorinated films were characterized. It was found that P(MMA-BA) latex particles gradually coagulated with P(PFA-BA) particles after adding emulsion polymerization constituents at the midstage of the suspension polymerization, and fluorinated composite particles with core-shell structure and larger size were obtained. The fluorine contents either on the film surface or in the bulk of the film and the films from SECP are higher than those from miniemulsion polymerization at high PFA feed ratio (more than 20 wt.%). The model of PFA-MMA-BA SECP was proposed according to the variations of particle features of the composite particles.