Robust, lightweight gelatin composite aerogel with outstanding thermal insulation

Thermal insulation materials with high mechanical strength and low thermal conductivity play an important role in the construction industry. In this study, a compound aerogel with stable performance, high strength, low density and good thermal insulation performance was successfully prepared by using gelatin as the base and layered bimetallic hydroxide (LDH) as the reinforcing phase. 3-aminopropyl triethoxylsilane was used to modify the surface of layered bimetallic hydroxide to enhance interfacial bonding. The results show that the gelatin/layered bimetallic hydroxide composite aerogel has high porosity (> 96%) and low thermal conductivity (0.034–0.037 W/(m K)), volume density as low as 0.035 g/cm3. The maximum compression strength and compression modulus are 1.05 Mpa and 9.82 Mpa, respectively. The improvement of the mechanical strength of the composite aerogel may be attributed to the two-dimensional layered nanosheets of LDH to construct the internal micro/nano structure of the composite aerogel. Outstanding mechanical and low thermal conductivity enable its application in high-performance thermal insulation materials.Graphical abstract