Facile synthesis of PEG-silica hybrid particles using one-step sol-gel reaction in aqueous solution

Abstract

A facile synthetic method for silica-PEG hybrid particles using one-step sol-gel reaction in aqueous solution is designed in this study. The preparation process of highly monodispersed hybrid silica spheres using organosilane molecules is applied to the synthetic method, which contains the self-hydrolysis step of poly(ethylene glycol) methyl ether-3-(triethoxysilyl) propyl isocyanate (PEGME-IPTES) monomers at high temperature of 80 degrees C for 2 days. Compared to the general sol-gel method and the sequential emulsion technique, our method is very facile and simple because (1) it just needs polymer-silane monomers without other silica sources and organic agents and (2) the reaction occurs in aqueous solutions. The size of particles is varied from 0.42 to 1.79 mu m, depending on the concentration of PEGME-IPTES precursor in the presence of NH4OH. Also, hybrid particles contain maximum 60 wt.% PEG polymer and have the surface area of 7.5 m(2) g(-1). Thermal stability of PEG polymer in hybrid particles largely increases compared with free PEG polymer and PEG polymer in PEG-grafted silica particles.