Preparation of Monodisperse Crosslinked Organic‐Inorganic Hybrid Copolymer Particles by Dispersion Polymerization

This study presents a new method for producing monodisperse crosslinked organic‐inorganic hybrid polymer particles in micron‐size by using simple dispersion polymerization. Firstly, highly monodisperse hybrid copolymer particles were prepared by conventional dispersion polymerization of styrene and 3‐(trimethoxysilyl)propyl methacrylate (TMSPM) in a methanol/water medium. It was very interesting to find that slightly crosslinked hybrid polymer particles were formed by this simple dispersion polymerization due to a partial condensation reaction between the adjacent silanol groups of the TMSPM during the polymerization. Secondly, for the hydrolytic condensation of the remaining trimethoxysilyl groups, post treatment by sol‐gel process was carried out to form an inorganic siloxane network, which provides the particle with high crosslinking density. In the proper conditions, monodisperse crosslinked particles could be produced in high TMSPM concentrations, up to 20 wt.‐%. In addition, the size monodispersity of the hybrid polymer particles was maintained after the sol‐gel process. Crosslinking with inorganic networks formed by the sol‐gel process was confirmed by a thermal analysis and a ²⁹Si NMR spectroscopy.

Synthesis of crosslinked organic‐inorganic hybrid polymer particles by dispersion copolymerization and post sol‐gel process.