Aerogels have been in existence for more than 80 years. Invented in 1931 by Dr. Samuel Kistler at the College of the Pacific in California, aerogel is a lightweight silica solid derived from gel in which the liquid component of the gel has been replaced with gas. When the liquid is removed, what remains is “puffed-up sand”, with up to 99% porosity. The result is an extremely low density solid with several remarkable properties, most notably its effectiveness as a thermal insulator.
The silica solids, which are poor conductors, consist of very small, three-dimensional, intertwined clusters that comprise only 3% of the volume. Conduction through the solid is therefore very low. The remaining 97% of the volume is composed of air in extremely small nanopores. The air has little room to move, inhibiting both convection and gas-phase conduction.
These characteristics make aerogel the world’s lowest density solid and most effective thermal insulator. The outstanding thermal properties of aerogels have been studied for decades, but Aspen Aerogels has developed a technically and economically viable form of aerogel for industrial insulation uses. Our unique process integrates aerogel into a fiber-batting reinforcement to create flexible, resilient, durable aerogel blankets with superior insulating properties.