Aerogels are porous ultralight materials. They are produced from a gel, in which the liquid component of the gel has been replaced with a gas through supercritical drying. They find application in areas such as catalysis, thermal insulation, drug delivery, gas storage, liquid absorption, and space and particle research.
Wim Thielemans and colleagues, University of Nottingham, UK, prepared mesoporous chitin nanowhisker aerogels by the aqueous self-assembly of chitin nanowhiskers under low-power sonication, followed by solvent exchange with ethanol and drying with scCO2. These aerogels were highly porous, with low densities and moderate surface areas. Shrinkage during drying was found to be extremely limited at only 4 %.
The aerogels also retained the crystalline structure and the thermal stability of the chitin nanowhiskers which could prove invaluable in many applications, and also displayed mechanical properties in the upper range of other reported aerogels.
These aerogels could find applications as thermal insulators, catalyst supports and for the construction of biomedical materials.