In order to achieve monodisperse particles with high content of antibacterial groups covalently bonded on surface, a bicationie viologen, N-hexyl-N-（4-vinylbenzyl）-4,4＇-bipyridinium bromide chloride （HVV） was devised as a surfrner in dispersion polymerization of styrene （St） using a mixture of methanol （or ethylene glycol） and water as media. Effects of content of HVV, its addition profile and composition of reaction media on particles size and incorporation of HVV moieties were mainly investigated. The attachment of silver and gold nanoparticles on particle surface under UV irradiation ascertained the surface-bonded HVV segments. SEM, TEM observations and XPS, zata potential measurements indicated that increase of initial HVV contents and addition of HVV （when polymerization had been performed for 3 h） led to grown particles and enhanced immobilization of HVV moieties. Using a mixture of ethylene glycol and water as reaction media, small particles （520-142 nm） with highly attached HVV moieties were prepared. Furthermore, antibacterial efficacy of the resultant particles against S. aureus was assayed, and particles with more HVV moieties anchored on surface demonstrated greater efficiency of antibacterial activity.
