Surface modification of monodisperse hydroxyl functionalized polymeric microspheres using ceric ammonium nitrate

The surface modification of monodisperse hydroxyl functionalized polymeric microspheres was carried out by utilizing a redox initiation system. Styrene, divinylbenzene and hydroxyethyl methacrylate were used as the second monomer in the seeded polymerization. An excessive amount of the second monomer emulsion was swollen into the polystyrene (PS) seed particles completely by controlling the medium solvency and swelling temperature. The hydroxyl functional groups were radicalized by the ceric ammonium nitrate in nitric acid solution, and the methyl methacrylate was reacted uniformly on the surface of microspheres. From the SEM, and FE-TEM measurements, highly monodisperse microspheres having a smooth surface, and polymethylmethacrylate (PMMA) coating layer were observed, respectively. The surface characteristics of the PS seed particles, hydroxyl functionalized and surface-modified polymeric microspheres were confirmed by utilizing FT-IR, XPS and thermal analysis.