Atom-transfer radical graft polymerization initiated directly from silica applied to functionalization of stationary phases for high-performance liquid chromatography in the hydrophilic interaction chromatography mode

Initiation of atom-transfer radical polymerization of a ,number of monomers ( styrene, methyl acrylate, 3-[N,N-dimethyl-N-( methacryloyloxyethyl) ammonium] propanesulfonate, butyl methacrylate, 2,3- epoxypropyl methacrylate) directly from chlorinated porous silica particles has been performed. The grafting has been confirmed and evaluated by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. This initiation technique results in a hydrolytically stable initial Si-C bond, tethering the polymer to the silica substrate. The resulting grafted particles have been used as separation materials for both reversed-phase and hydrophilic interaction chromatography.