The crosslinked polystyrene particles possessing photofunctional N,N-diethyldithiocarbamate groups on their surface were prepared by free-radical emulsion copolymerization of a mixture of styrene, divinylbenzene and 4-vinylbenzyl N,N-diethyldithiocarbamate with redox system as an initiator under UV irradiation. In this copolymerization, the inimer 4-vinylbenzyl N,N-diethyldithiocarbamate acted the formation of hyperbranched structures by living radical photopolymerization. The particle sizes (number-average particle diameter = 214-523 nm) were controlled by varying the feed amount of surfactant and size distributions were relatively narrow. Subsequently, core-shell particles were synthesized by photoinduced atom transfer radical polymerization approach of methyl methacrylate initiated by photofunctional polystyrene particles as a macroinitiator. Such core-shell particles were stabilized sterically by grafted chains in organic solvents. (c) 2007 Wiley Periodicals, Inc.