Controllable preparation of monodisperse polystyrene microspheres with different sizes by dispersion polymerization

Monodisperse polystyrene (PS) microspheres with different sizes were prepared by dispersion polymerization in dispersion media of ethanol/water and isopropayl alcohol/water, respectively. The effect of polarity of the dispersion medium, stabilizer and initiator concentration on the average sizes and size range were evaluated. The results show that monodisperse PS microspheres with different sizes could be prepared in dispersion media of ethanol and isopropyl alcohol/water when appropriate initiator and stabilizer concentrations were employed, and the latter is a more appropriate medium to prepare uniform PS microspheres. It was found that the microsphere sizes reduced with increasing water content in the dispersion medium. Furthermore, in isopropyl alcohol/water dispersions, the average sizes decreased with increasing stabilizer concentration.