Nonsupercritical 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 non-supercritical drying procedure. These results demonstrated the physical properties comparable with those of aerogels obtained by supercritical, drying can be obtained. © 2008 Wiley Periodicals, Inc.