Bismaleimide Bridged Silsesquioxane Aerogel with Excellent Heat Resistance: Effect of Sol-Gel Solvent Polarity

Owing to the poor heat-resistance and intrinsic weakness of the bridging moieties in aerogel matrix, it remains greatly challenging to fabricate highly thermostable and toughened silsesquioxane aerogel. By utilizing bismaleimide as the bridging part and optimizing the solvent polarity, lightweight (ρ < 0.09 g/cm3), compressible (80% strain) and superhydrophobic (CA ≈ 150o) bismaleimide bridged silsesquioxane aerogels (BMIT-BSAs) are constructed. The microstructure and compressive modulus of BMIT-BSAs can be tuned by the sol-gel solvents with different polarity. Moreover, a stable low-temperature wettability at -196 oC and significantly increased initial deposition temperature of 336oC for both N2 and O2 atmosphere were measured, demonstrating a wide temperature tolerance of BMIT-BSAs.