SEED DISPERSION POLYMERIZATION TO MICRON-SIZE MONODISPERSE POLYMER PARTICLES

Seed dispersion polymerization of methyl methacrylate (MMA) in the pre sence of monodisperse PMMA particles was carried out in an aqueous met hanol using poly(methacrylic acid) stabilizer. The polymerization usin g 2.5 mu m-sized seed particles gave monodisperse PMMA particles in th e diameter up to 4.9 mu m. The solvent composition and monomer concent ration greatly affected the polymerization behavior. Under appropriate conditions, monodisperse PMMA particles in the diameter up to 8.9 mu m was prepared from 4.6 mu m-sized seed particles. The seed dispersion polymerization of styrene in the presence of the seed particles produ ced monodisperse PMMA-polystyrene particles in the micron range. The p articles were supposed to have a structure consisting of PMMA-core and polystyrene-shell from ESCA analysis.