Stephane Fabrice Rouanet

Development and processing of aerogels in a windowed autoclave

Processing of aerogels in a windowed autoclave has shown that the drying process and solvent play important roles in gel quality. Excellent aerogels have been obtained using acetone as the solvent during gel formation, followed by exchange with liquid carbon dioxide with gradient control, and evacuation under supercritical conditions. Observation of the drying process showed that contact between solution discontinuities and the aerogel during the solvent exchange process caused gel deformities. Control of the solvent exchange and elimination of gradient fronts resulted in outstanding aerogel quality. The ability to observe the process in a windowed autoclave allowed this improved understanding of key variables.