Abstract: A steady miniemulsion copolymer of trifluoroethyl methacrylate(TFMA), n-buty acrylate(BA) and styrene(St) was prepared by using predissolved polymer and hexanediol (HDL) as a costabilizer, AIBN as initiator, SDS/S100/OP as a complex emulsion system. The relationships of polymerization conditions between the final conversion and polymerization stability were discussed in detail. The optimal polymerization condition is 0.7% AIBN, 2% HDL, 0.5% predissolved polymer and m(OP):m(SDS):m(S100) = 2.5:1:0.3. The molecular weight and composition of copolymer were demonstrated by GPC, FT-IR, 1H-NMR, DSC and TGA. The result was showed that HFMA is effectively involved in the copolymerization, the fluorinated acrylate copolymer has a narrower molecular weight distribution. Add a small amount of predissolved polymer can not only improved the emulsion stability but also improved the hydrophobic properties of latex films. After perfluoroalkyl groups were introduced into polymer chains, the wetting-resistance, the water-resistance and the thermal stability of the latex films were evidently enhanced.

Key words: Miniemulsion polymerization, Fluorinated acrylate, Costabilizer, Latex films, Predissolved polymer