Synthesis of methacryloxypropyltrimethoxysilane grafting silica cryogels using xylene as solvent

Grafting methacryloxypropyltrimethoxysilane (MPS) onto the surface of silica nanoparticles is the most common approach in surface chemical modification. Traditionally, ethanol or toluene was used as solvent in the grafting process. However, using ethanol as solvent brought about poor grafting result and toluene being regulated was also not an ideal grafting solvent. In order to overcome these disadvantages, we widen the grafting solvents and a novel solvent of xylene was utilized to prepare MPS grafting silica cryogels in this study. The hydrolysis of MPS was in the mixture of methanol and water using diluted hydrochloric acid solution as a catalyst. Both original and MPS-grafted samples were characterized by fourier transform infrared spectrometer (FTIR), thermogravimetric analysis (TG) and other methods. The results showed that xylene is an effective solvent in the process of grafting and the MPS was chemically bonded onto the surfaces of nano-silica particles.