Preparation of SiO2/PMMA composite particles via conventional emulsion polymerization

A series of SiO2/PMMA composite particles with different morphologies were prepared by conventional emulsion polymerization by the aid of acid-base interaction between the silanol groups of unmodified silica particles and the amino groups of 4-vinylpyridine. In this approach, no surface treatment for nanosilica particles was required. The morphologies of composite particles, for example, multicore-shell, raspberry-like, and conventional core-shell, could be controlled by modulating emulsifier content, monomer/silica ratio, silica size, and monomer feed method. The possible particle formation mechanisms were discussed. (c) 2006 Wiley Periodicals, Inc.