Surface-initiated atom transfer radical polymerization (ATRP) of methyl rnethacrylate (MMA) and 2-hydroxyethyl rnethacrylate (HEMA) was carried out separately on spherical silicon gel with surface-tethered alpha-bromoester initiator in aqueous media at ambient temperature. The chemical composition of the PMMA and PHEMA blushes grafted from the silicon gel surface was characterized by FT-IR spectroscopy and Xray photoelectron spectroscopy (XPS). As a result, two kinds of new inorganic/organic hybrid particles were obtained. The thermogravinmetric analysis (TGA) results indicated that the content of the grafted polymer was fairly high. The scanning electron microscope (SEM) images revealed the significant change of the morphology between the pristine and polymer modified particles and the polymer modified particles owned core-shell structure. The polydispersity index (PDI) of PMMA blushes was low and the "living" character of the PMMA chain end was further ascertained by the subsequent growth of new MMA, using the PMMA blushes as the macroinitiators. (c) 2005 Elsevier B.V. All rights reserved.