Preparation and properties of bacterial cellulose aerogel

Abstract

Bacterial cellulose (BC) aerogel was obtained by treating BC hydrogel in super critical fluid of ethanol at 6.38 MPa and 243°C. The apparent density of the BC aerogel was 6 Mg/cm3 and the porosity was more than 99 vol%. Scanning electron microscopy results showed that micro fibrils with 20 - 60 nm developed into a highly branched three-dimensional network structure. Compression stress-strain measurement indicated that the stresses of BC hydrogel were 20 kPa at 60% strain and 65 kPa at 80%, while the stresses of BC aerogel were 54 kPa at 60% strain and 140 kPa at 80%. If the BC aerogel was immersed in organic solvents, various kinds of organogels were obtained.