Preparation of Functionalized SiO₂ Microspheres by One Step Method

Functional silica microparticle is a kind of important inorganic non-metallic oxide with a wide range of applications in many fields due to its excellent chemical and thermal stabilities. Post modification is the most common functional method, but, low efficiency. In this paper, a new acid hydrolysis and subsequent alkaline condensation method was developed to prepare SiO₂ microspheres with functional groups on surface by condensing or co-condensing functional organosilane precursors (γ-Aminopropyltriethoxysilane (APTES), γ-Mercaptopropyltriethoxysilane (MPTES) and γ-Mercaptopropyltrimethoxysilane (MPTMS) etc) with phenyltrimethoxysilane (PTMS). Series of characterization methods, such as IR, XPS and Raman, demonstrated that the surface of the as-prepared SiO₂ microspheres was successfully functionalized with amine or sulfydryl groups. This method may provide a reference for one-step preparation of functional SiO₂ microspheres.