Aerogel is a low-density material derived from a gel in which the liquid component of the gel has been replaced with air or nitrogen. The result is an extremely low density solid with several remarkable properties, most notably its effectiveness as a thermal insulator.

Aspect and properties : The nanostructure of aerogels and xerogels (pore size between 20 and 40 nm) gives them an extremely low thermal conductivity (around 0.02 W/m.K in normal temperature and pressure conditions).

Silica aerogels can either be prepared in monolithic form, powder or granule forms which can also give access to composite materials by impregnation of various fibres or by mixing with miscellaneous polymers.

Silica aerogels and xerogels