Tetramethoxysilane (TMOS) gels were synthesized and subsequently aged in various silanes, including TMOS, methyltrimethoxysilane (MTMS), and dimethyldimethoxysilane (DMDS). The surface area, pore structure and hydrophobicity were studied using nitrogen and water sorption measurements. 29Si MAS-NMR was also used for analyzing the reactions during aging. High surface areas above 1000 m2/g were obtained from the silica gels aged in TMOS and DMDS. The former has a large mesopore size of 62 angstrom and the latter has a small mesopore size of 28 angstrom. It has been found that precipitation of silane stiff layers and/or cross-linking within the pores are the primary mechanisms through which the pore structure and hydrophobicity of the gels are modified.
|Original language||English (US)|
|Number of pages||6|
|Journal||Materials Research Society Symposium - Proceedings|
|State||Published - 1995|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials