Preparation and film properties of SiO₂@P(MMA/BA/3FMA) composite nanoparticles

Nano-SiO₂@P(MMA/BA/3FMA) core-shell composite nanoparticles were synthesized by emulsion polymerization with the modified nano-SiO₂ from tetraethyl orthosilicate(TEOS) hydrolysis as the core and the fluorinated copolymer of methyl methacrylate(MMA), n-butyl acrylate(BA) and 2, 2, 2-trifluoroethyl methacrylate(3FMA) as the shell. In order to overcome the agglomeration of nano-SiO₂ particles and to improve the chemical integration to the shell copolymer, vinyltrimethoxysilane(VTMS) was used as the surface modifier for nano-SiO₂ particles. Fourier transforms infrared spectroscopy(FTIR), transmission electron microscope(TEM), dynamic light scattering(DLS), static contact angles(SCA), X-ray photoelectron spectroscopy(XPS) and thermogravimetric analysis(TGA) were employed to characterize the structures of the composite nano-particles and the film properties. The results indicated that SiO₂@P(MMA/BA/3FMA) composite presented the uniform spherical core-shell partials with 40-50 nm in diameter. 25%(Mass fraction) 3FMA gave the lowest surface energy due to the migration of fluorine to the surface during the film formation. The thermal behavior of SiO₂@P(MMA/BA/3FMA) was improved with the increase of 3FMA content.