Aerogel is a porous material in which the liquid component of a gel has been carefully dried out and replaced by gas, leaving a solid made up almost entirely of air. It long held the record as the world’s lightest solid and is also one of the most effective insulators in existence. While its inventor published his discovery in 1931, aerogel remained impractical for many decades due to its fragility and brittleness. NASA turned to the material to keep rocket fuel at cryogenic temperatures and worked with industry to create the world’s first practical, flexible aerogel blankets in the 1990s. Since then, aerogels have become widely used as insulation in subsea systems, oil refineries, industrial buildings, homes, refrigerators, jackets and shoe inserts.
Read more: http://spinoff.nasa.gov/Spinoff2010/cg_2.html
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