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(dimethysiloxane)(PDMS) modified silica gels were prepared by a two step acid/base catalyzed solgel 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.