What do you get when you dehydrate ultralight material made of gel and gas, leaving only 99% air? Aerogel, that’s correct! Nicknamed “frozen smoke” or “solid cloud,” this ethereal material has been creeping its way into products since 1931. Aerogel is the lightest solid ever to be created. It is durable enough to support the weight of a thousand bricks and endure the vacuum of space but is as fragile as a snowflake.
The synthetic ultralight material is derived from silica gel, that is substituted with gas. The result is a stable gas with very low density and remarkably low thermal conductivity. 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 over a bet. In 1931 Samuel Stephen Kistler bet Charles Learned to see who could replace the liquid inside of a jelly jar with gas without causing shrinkage. Dr. Samual Kistler won by inventing Aerogel.
Futuristic Aerogel looks like the slice of a cloud but with some pretty remarkable properties. It adds a shielding screen because air is a terrible conductor of heat. It offers an ultra sheer layer of protection between a heat source and the object.
Aerogel is made up of a variety of substances, and scientists have come up with over thirty different recipes depending on how the material will be used. Aerogel’s main ingredient is silica, one of Earth’s most abundant minerals. The scientists cycle the wet Aerogel through many phases of heating and cooling, pressure, and drying out time.
The resulting Aerogel is almost entirely air, making it the most lightweight solid we know to man. Due to the air’s inability to conduct much heat, it is an excellent insulator. Applications such as providing insulation for the Mars Rover is just one of the commercial products using Aerogel.
You can find Aerogel in applications such as modern cosmetics, paints, wetsuits, roofing materials, and carpets, to name a few. It is even making its way into the fashion industry by being incorporated into incredibly thin, warm, yet very fashionable winter wear. It’s most useful application to date is in the area of oil spill-cleanup. Aerogel’s non-toxic, highly porous nature, the potential for a large surface area, and the fact it can hold up to seven times its weight makes it one of the most valuable cleanup tools.
Not all Aerogel can be easily broken, but many applications of this material have limitations due to the substance’s instability. “The first thing most people do when they touch a piece of silica aerogel for the first time is to shatter it into a million pieces,” says the E.O. Lawrence Berkeley National Laboratory website on silica aerogels.
Classic Aerogel can hold a brick a thousand times its weight by volume. The catch is the block must be placed feather-light and very smooth. There must not be any cracks in the Aerogel itself, or it will shatter. Despite its brittleness, Aerogel is very strong. It can support up to 4,000 times its weight making this ultralight material ten times stronger than steel.
With seemly magical qualities, scientists are looking at future applications for Aerogel in such products as capacitors, lasers, spacecraft, and there is an excellent potential for fuel cells for energy-efficient automobiles. However, we have a long way before we see the unstable Aerogel in significant product production. More research needs to be conducted to make this ultra-light material affordable for large scale operations.