Abstract
The effects of the amount of methanol and that of the ionic comonomer on the particle size have been studied for the soap-free emulsion polymerization of styrene. In the case of poly (methyl methacrylate) microspheres, the particle size was controlled both by the ionic comonomer concentration and by the methnaol content. In the case of polystyrene microspheres, the particle size was not controlled precisely by the methnaol content, because the solubility of styrene in methanol-water media was lower than that of methyl methacrylate. The solvent composition was thus changed by using ethanol. The results show that the particle size decreased with decreasing content of ethnaol and with increasing ionic comonomer concentration. We there by succeeded in controlling the particle size, which ranges from 100 nm to 1 μm, by changing the content of ethanol and that of the ionic comonomer.
