Synthesis of SiO 2 /PS composite particles via emulsion polymerization

SiO 2 particles prepared by Stöber method were modified using 1,3,5,7‐tetravinyl‐1,3,5,7‐tetramethylcyclotetrasiloxane (Vi‐D 4 ), and SiO 2 /polystyrene (PS) composite particles with core‐shell structure were synthesized adopting mulsion polymerization of PS in a water–ethanol medium. The products were characterized by infrared spectra, X‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and Zetasizer analyzer. The average diameter of SiO 2 particles prepared by Stöber method was about 80 nm, the SiO 2 particles were modified using the molar ratio of Vi‐D 4 and SiO 2 particles 1 : 10 (the dosage of Vi‐D 4 benever too much), and the size of modified silica particles was about 90 nm. The infrared spectra indicated that the Vi‐D 4 had bonded to the silanol groups on surface of SiO 2 particles, and XPS indicated the grafting efficiency of Vi‐D 4 on surface of SiO 2 particles had reached 90%. The infrared spectra indicated the PS had been incorporated with SiO 2 particles, and TEM indicated the composite particles have obvious core‐shell structure. The suitable size of SiO 2 particles should be lower than 200 nm, and the optimum volume ratio of ethanol and water should be 1 : 9 or 1 : 4. A kind of monodisperse SiO 2 /PS composite particles having function of self‐assembling was successfully and effectively synthesized. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011