Microspherical hydrogel particles based on silica nanoparticle-webbed polymer networks

Abstract

Spherical hybrid hydrogel microparticles were facilely fabricated by particulation of an aqueous mixture of hydrophilic copolymer with alkoxysilyl side chains and silica nanoparticles in water/silicone oil suspensions. Inside the aqueous phase, the copolymers were webbed with silica nanoparticles to form polymer network through the silane coupling reactions between reactive side chains of copolymer with the silanol groups on silica nanoparticles. An amino-functionalized silane coupling reagent was used to terminate remaining reactive sites at the surface of the hydrogel particles to avoid aggregation. The size of the spherical hydrogel particles was well controlled by the viscosity of the silicone oil, whereas their properties were controlled by composition. The mechanical strength of the microspherical hybrid hydrogel was increased significantly with increasing the concentration of silica nanoparticles.