Fine particles of poly(N-vinyl-2-pyrrolidone-co-2-methylene-1,3-dioxepane) (poly(NVP-co-MDOP)) were produced by means of aerosol solvent extraction system (ASES). Dichloromethane (DCM) was used as solvent and supercritical carbon dioxide was used as antisolvent. Mean diameter of obtained polymer particles ranged from 0.18 to 0.26 mu m. The effects of temperature, pressure and solution flow rate on the particle size were investigated. And the relation of particle size and initial drop size was also considered. The size and morphology of particles were investigated by scanning electron microscope. (c) 2006 Elsevier B.V. All rights reserved.