Preparation of compressible silica aerogel reinforced by bacterial cellulose using tetraethylorthosilicate and methyltrimethoxylsilane co-precursor

Abstract

Silica aerogel is one of the most attractive insulation materials but has not been broadly applied yet because of limitation of its fragile nature. In this work, we synthesized a compressible bacterial cellulose/silica aerogel composite from the co-precursor of tetraethylorthosilicate and methyltrimethoxylsilane by a two-step acid-base catalyzed sol-gel method followed by supercritical CO2 drying. This aerogel composite possessed a series of excellent properties: standing the considerable strain, high resilience, dust-free, low density of 0.066g/cm3 and low thermal conductivity of 0.0292W/(m·K) along with hydrophobicity with a water contact angle of 147°. Weight loss analysis indicated that the thermal stability of the as-prepared composites was about 270°C which primarily depended on the thermal stability of the bacterial cellulose. These outstanding properties were attributed to the Interpenetration Polymer Network structure formed via the co-precursors and the bacterial cellulose and the excellent fabric of the aerogel retained by the supercritical CO2 drying. The results suggest that the as-prepared aerogel composite has potential applications as a suitable insulation material with dust-free and resilience.