ENHANCED AEROGEL FABRICATION
Ben M. Gauthier (Ann Anderson), Department of Mechanical Engineering, Union College, Schenectady, New York 12308

Referred to as frozen fog, aerogels are nanostructures consisting of approximately 90-99% air. With the lowest density of any solid, aerogels have the lowest known thermal, electrical, and acoustical conductivities. Aerogels are fabricated by applying sol-gel chemistry to produce a polymer matrix, and a carefully controlled solvent exchange to replace the original solvent (usually an alcohol) with the desired solvent, air. The underlying obstacle in the fabrication of an aerogel is that any surface tension in the gel will inevitably lead to fracture. One method of fractureless evacuation involves a supercritical fluid exchange with CO2 in a pressure vessel. While specimens can be produced this way, the method is costly, and monolithic sizes are limited by the size of the pressure vessel. Ambient pressure techniques are also used, but have not yet proven fully reliable. A third solution, recently developed at Lawrence Livermore uses the supercritical state of a fluid in a one-step, contained mold process. My presentation will describe a new technique developed at Union College to manufacture aerogels based on the contained mold process. This approach, if successful, could yield aerogel monoliths in minutes, as opposed to hours or weeks, with reduced costs and minimal waste.