Aerogels make cool insulators.Sometimes known as solid smoke, the ultralight ul·tra·light n. A recreational aircraft constructed of lightweight materials such as aluminum, graphite composites, or high-strength plastics, having an engine of roughly 15 to 40 horsepower and often resembling a hang glider with wings. materials called aerogels are showing promise as insulators (SN: 11/17/90, p. 316). In fact, carbon-based aerogels made with resorcinol-formaldehyde can insulate better than any other material known, Xianping Lu of the University of Wurzburg in Germany and his colleagues report in the Feb. 21 Science. The researchers tested the insulating potential of several of these red, gossamer solids by placing a platinum wire through a small sample of each, passing an electrical current through each wire and then measuring how hot the wires got. The results show that the aerogel aerogel, any of a group of extremely light and porous solid materials; the lightest is less than four times as dense as dry air. Aerogels are produced from certain gels (see colloid) by heating the gel under pressure, which causes the liquid in the gel to become consisting of 88 percent air conducts one-third as much heat as a typical polyurethane foam Noun 1. polyurethane foam - a foam made by adding water to polyurethane plastics polyfoam polyurethan, polyurethane - any of various polymers containing the urethane radical; a wide variety of synthetic forms are made and used as adhesives or plastics or insulator. The aerogel's many tiny pores make it difficult for trapped air to move and carry heat away from the wire, says Richard W. Pekala, who helped develop aerogels at the Lawrence Livermore Lawrence Livermore may refer to:
These materials could replace insulating foams made from chlorofluorocarbons chlorofluorocarbons (klōr'əfl  r`əkär'bənz, klôr'–) (CFCs), organic compounds that contain carbon, chlorine, and fluorine atoms. , but first scientists must develop ways to make large quantities cheaply, Pekala notes.
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