Microstructural and Physical Properties of Organically Modified Silica Gels Prepared by Two-Step Sol-Gel Process

초록

The relative rates of hydrolysis and condensation during sol-gel synthesis were greatly affected by pH of the starting sol. resulting in materials with different microstructure. Two-step acid/base catalysis can produce gels with properties intermediate to those of single acid or base-catalyzed gels. In this study, Poly(dimethylsiloxane)(PDMS) modified silica gels prepared by a two step acid/base catalyzed sol-gel process with various base/acid molar ratios ranging from 0.2 to 1.2. The influence of pH on the molecular structure, microstructure and subsequent properties of SiO2/PDMS hybrid gels were examined with FT-IR, SEM and BET analysis.