Development of a Super-Insulating Aerogel Window: Production of Monolithic Silica Aerogel

While windows are designed to be aesthetically appealing features on buildings, they contribute greatly to overall building energy losses. A significant amount of energy can be lost through fenestration due to poor insulation, leakage, or heat transfer through a thermally conductive material. One promising alternative to traditional window insulation is silica aerogel. The benefits of aerogel-based fenestration over standard glass-based fenestration systems include its low density, low thermal conductivity, and high translucency. If a traditional window were replaced with the super-insulating aerogel window, less energy would be required to heat/cool interiors of buildings. To make an aerogel, a liquid precursor solution is poured into a sealed mold and placed between the platens of a hydraulic hot press. The solution gels while the hot press heats it to a state above the critical point of the solvent and then releases the solvent super-critically. The process is known as Rapid Supercritical Extraction (RSCE); it takes approximately 6.5 hours to make an aerogel from the liquid precursor solution with RSCE. The focus of this project was to make large aerogel monoliths that could be used to make an aerogel window. To do this, a new mold with improved contact surfaces and pressure and temperature instrumentation was designed and modified. The presentation will cover the effects of processing parameters, such as press force and gel time, and mold used on the quality of silica aerogel.