Influence of Starting Composition and Gelation Temperature on the Ratio between Meso- and Macropore Volume in Silica Xerogels with Bimodal Pore Structure

Abstract

The impact of gelation temperature and starting composition (solvent, silica, and polymer content) on the pore structure of silica xerogels with bimodal meso-/macropore structure is explored. Using statistical regression models, precise control over the pore structure is demonstrated, a challenge in previous studies. Higher gelation temperatures and increased polyethylene oxide (PEO) content enhance the mesopore volume, while higher solvent content and reduced polymer content increase the macropore volume. The ratio of mesopore to macropore volume can be effectively adjusted, facilitating the design of xerogels with tailored properties. These findings optimize silica xerogels with bimodal pore structure for applications in catalysis, thermal insulation, and other advanced technologies.