Three core-shell fluoroacrylate copolymer latices with different fluorinated side chain structure were synthesized in this article by semicontinuous seed emulsion polymerization, using butyl acrylate (BA) and methyl methacrylate (MMA) as acrylate monomer and trifluoroethyl methacrylate (TFEM, C6H7O2F3), hexafluorobutyl methacrylate (HFBM, C8H8O2F6), and dodecafluoroheptyl methacrylate (DFHM, C11H8O2F12)as fluorine-containing acrylate monomer. The core-shell fluoroacrylate copolymer latices were named as BA/MMA/TFEM, BA/MMA/HFBM, and BA/MMA/DFHM, respectively. The latex particle morphology and the particle size were determined by transmission electron microscopy and differential scanning calorimetry. The final chemical structure of the latex was analyzed by NMR. The effect of the fluorinated side chain on the core-shell copolymer latex and film properties, as well as on the superiority of core-shell copolymer latex to general fluoroacrylate copolymer latex was investigated by energy dispersive X-ray detector, thermogravimetric analysis, and the determination of contact angle. The analysis results indicated that the particle of fluoroacrylate copolymer latex presented uniform sphere core-shell structure. Compared with core-shell BA/MMA/TFEM and BA/MMA/HFBM, BA/MMA/DFHM exhibited not only better surface property as increasing temperature but also better thermal stability. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 1615-1621, 2009