engleski

Cellulose aerogels – from characterisation to implementation

Aerogels are a diverse class of open-pore solid- network materials that compile a range of disparate and extreme properties into a single material. Generally, aerogels are known for their high porosity (>90%), high specific surface area, with pores in meso/macro range. Several properties, such as very low thermal conductivity has been utilised for thermal insulation, extreme porosity for catalyst supports, etc. Recently, a new generation of so-called bio-aerogels which are biomass-based, mainly polysaccharide-based, raise special attention as they forester the concepts of availability, renewability, biocompatibility, and non-toxicity. Combination of such materials and general aerogel properties suggests considering of acoustic insulation application, particularly as this route of application did not yet develop. In this work, two different series of samples are investigated ; using either NaOH solvent (3–7 wt% of microcrystalline cellulose, MCC, 8 wt% NaOH) or EMImAc/DMSO solvent (50/50 wt/wt ; 3–10 wt% of MCC) and drying process based on supercritical fluid and freeze-drying. All freeze-dried samples turn out to be too fragile for a reliable characterisation of mechanical properties, which heavily diminishes their possible application. Samples dried by supercritical CO2 drying show more compact habitus which was confirmed by SEM and nitrogen adsorption/desorption isotherms and thereof are subjected to further refractometric acoustic characterisation.

bio-aerogels, cellulose, supercritical CO2 drying

nije evidentirano