Photofunctional polymer as silane coupling agent (PFD) was prepared by free radical copolymerization of 4-vinylbenzyl N,N-diethyldithiocarbamate (VBDC) and methyl methacrylate (MMA) in the presence of (3-mercaptopropyl)trimethoxysilane (MPMS) as chain transfer agent. Next, silane (SiO2; the average diameter D-n = 192 nm) nanoparticles was surface-modified with PFD and 3-(trimethoxysilyl)propyl methacrylate (gamma-MPS) by covalent bond formed between silanol groups and silane coupling agents. The PFD and gamma-MPS functionalizations changed the silica surface into hydrophobic nature and provided grafting initiation sites and methacrylate terminal groups respectively. We performed the construction of hybrid nanocomposites by Using these modified SiO2 nanoparticles. It Was found from electron microscopy observations that SiO2 particles v,ere packed into repeating cubic arrangements in a poly(methyl methacrylate) (PMMA) matrix such as collodial crystals. (C) 2009 Wiley Periodicals, Inc. I Appl Polym Sci 112: 2434-2440, 2009