Preparation of Raspberry-like Poly(styrene-co-2-vinylpyridine)/Silica Colloidal Nanocomposite Particles byAlcoholic Dispersion Polymerization

The field of polymer nanocomposites is rapidly growing an interest. Recently, there has been an increasing interest in the synthesis of colloidal nanocomposite particles. Such synthesestypically involve either emulsion or dispersion polymerization, although other techniques such as mini-emulsionpolymerization or the entrapment of preformed polymer during sol-gel processes have also been described[1]. There has been a lot of potential applications in the areas of drug-releasesystems, coatings, catalysis, and diagnostics. In this article, we present a preparation method for raspberry-like hybrid particlesstyrene/2-vinylpyridine (2-VP) copolymer (core و ) SiO2 (shell) via dispersion polymerization. Micrometer-sized silicastabilizedpolystyrene latex particles and submicrometer-sized polystyrene silica nanocomposite particles have been prepared in alcoholic media in the presence of a alcoholic silica sol asthe sole stabilizing agent. Micrometer-sized near-monodisperse silica-stabilized polystyrene latexes are obtained when the polymerization is initiated with 2,2- azobisisobutyronitril(AIBN) initiator