ABSTRACT
Cellulose, the most abundant renewable biomass on earth, has plentiful hydroxyl groups in the molecules, allowing for the formation of strong intra- and intermolecular hydrogen bonding. The effect of these interactions results in a physical cross-linking network required for the cellulose gels and further for aerogels. The combination of high porosity and surface area, superior processability and mechanical properties and excellent biocompatibility and biodegradability makes cellulose-based aerogel a valuable biomass as a new-generation aerogel following the inorganic oxide and the synthetic polymer aerogels. The cellulose-based aerogels can be categorised into neat cellulose and cellulose-derived aerogels according to the type of starting cellulose. The former includes cellulose II aerogels prepared via dissolution–regeneration method and cellulose I aerogels prepared without dissolving in solvents. Cellulose aerogels have been modified via chemical reactions or physical blending in the different stages of aerogel preparation to obtain cellulose-based composite aerogels. The flame-retardant modification of cellulose-based aerogels is a crucial task for expanding its applications.
