On July 18th the Academites had the opportunity to tour the Aerogels Laboratory. Aerogels are a revolutionary porous insulation material that consists of 96% air. Most aerogels are silica-based, like glass, and as a result are extremely fragile. Therefore, research is being conducted at NASA Glenn to discover new ways to revolutionize this amazing material via strengthening and heat capacity.
Aerogel is manufactured through a solid-gel process. A rapid, exothermic reaction combines APTES (3-Aminopropyltriethoxysilan) and TMOS (Tetramethylorthosilicate) in an ethanol solvent to make the gel. In order to remove the solvent from the pores and to maintain structural integrity of the new gel, it is necessary to utilize supercritical fluid extraction. This prevents the capillary forces from collapsing the delicate structure. The porosity of the material can be controlled by varying different variables, including the formulation of reagents, the setting time, and differing the monomer and/or solvent.
Research being conducted with aerogels includes Aspen aerogels, which are organic aerogels. Here, polyimides are used to make the material more flexible, which proves useful for a re-entry vehicle. Alumina-Silicate gels are also being evaluated for integration into Alumina fiber felts. These materials are also applicable for thermal coatings in EVA’s, houses, windows, etc. Other uses of aerogels have been particulate collection and radioactive protection.