Silica-PMMA core-shell and hollow nanospheres

Monodispersed silica-polymer core-shell nanospheres (CSNs) were prepared by emulsion polymerization. To coat the cores by polymer, silica nanoparticles were modified by 3-(trimethoxysilyl) propyl methacrylate (MPS). The thicknesses of polymer shells were found to be dependent on the amount of monomer and grafted silica nanoparticles, the concentration of emulsifier and the sizes of grafted silica nanoparticles, and the morphologies of CSNs were affected by the kind of monomer. The formation mechanism of SiO2-PMMA CSNs was speculated. In addition, we investigated the formation of hollow polymer nanospheres.