Environmentally friendly zwitterionic fluorocarbon surfactant for high-efficiency emulsion polymerization of fluoropolymers

Fluorocarbon surfactants are widely used, especially in the emulsion polymerization of fluoropolymers, due to their high surface activity, excellent stability, and excellent compatibility. However, the long-term environmental pollution of perfluoroalkyl and polyfluoroalkyl groups in fluorocarbon surfactants has made them banned. Here, we designed and prepared an environmentally friendly zwitterionic fluorocarbon surfactant (PFSC) through shortening fluorocarbon chains and covalent bonding them with the zwitterionic groups, and further demonstrated the effect on the emulsion polymerization of fluoropolymers. The results showed that the surface tension of the emulsion after adding PFSC reached 12 mN/m at a concentration above 0.05%, which is significantly superior to that of perfluorooctanoic acid (PFOA). The study also examined the reaction kinetics, emulsion particle size, and emulsion stability during the emulsion polymerization reaction. The results demonstrated that the fluorinated surfactant exhibits excellent emulsification effects and can serve as an alternative to PFOA. This work presents the synthesis strategy of a new environmentally friendly zwitterionic fluorocarbon surfactant for high-efficiency emulsion polymerization of fluoropolymers.