Process and mechanism of surface modification of silica with silane coupling agent APTS

After modification using gamma aminopropyltriethoxysilane(APTS), the silica surface demonstrates unique performance in the applications to rubber, plastics, catalyst, chromatography column, adsorbent, biologicals and pharmaceuticals. A large number of literatures focus on APTS modification of silica in the specific application background for achieving ideal and controllable modification. Summarizing these scattered results and discoveries can effectively promote research further on a new stage. Based on an analysis of literatures, the mechanism of reaction, process of modification, kinetics of reaction, stability and structure of the modified layer are reviewed. The existing problems in the current state of the research and the directions for further research are proposed.