Preparation of Monolithic Silica Aerogel via Ambient Pressure Drying

Monolithic silica aerogel was prepared through sol-gel process under ambient pressure drying with industrial water glass as silica source, formamide as catalust and glycol as DCCA. The effects of type and concentration of acids on properties of silica areogel was investigated. The exterior and microstructure of silica aerogel was observed, and the performance of aerogel was examined, the results show that type of acids has distinct effects on monolithic silica aerogel, complete monolithic silica aerogel was obtained by using acetic acid. When the concentration of acetic acid is 1.2 mol·L-1, the density, porosity and contraction percentage are 0.22 g·cm-3, 90%, and 11%, respectively.