Non-supercritical synthesis of microporous gels

In this work, the development of microporous gels using a novel degradation process not involving supercritical fluids is proposed. Photosensitive organic–inorganic hybrid sols in an alcoholic solution based on TEOS and an organic modified alcoxysilane were gelled by photopolymerization, and then dried at ambient pressure before sintering at 550°C. The result was a microporous gel with porosity higher than 90%. Chemical, physical, thermal, and mechanical characterizations were carried out on the microporous gel obtained by the nonsupercritical drying procedure. These results demonstrated the physical properties comparable with those of aerogels obtained by supercritical drying can be obtained.