The emulsifier-free core-shell polyacrylate latex nanoparticles containing fluorine and silicon in shell were successfully synthesized by emulsifier-free seeded emulsion polymerization with water as the reaction medium. The silicon-containing fluorinated polymer could be fixed on the surface of polyacrylate nanoparticles due to the formation of the crosslinked network structure. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis indicated that the obtained emulsifier-free core-shell nanoparticles were uniform and possessed narrow size distributions. The core-shell structure and chemical components of the emulsifier-free core-shell nanoparticles were investigated by TEM and Fourier transform infrared (FTIR) spectrometry, respectively. X-ray photoelectron spectroscopy (XPS) analysis and contact angle measurement on the latex films proved the propensity of fluorine and silicon enrichment at film-air interface. In addition, the thermal stability of the latex films was improved with increasing the concentration of fluorine and silicon. (c) 2007 Elsevier Ltd. All rights reserved.