Silica aerogel composites with excellent thermal insulation for building applications

In high altitude regions with low air pressure, the thermal insulation performance and thermal stability of building insulation materials are more demanding. Developing effective thermal insulation materials for buildings is crucial for achieving energy efficiency and reducing emissions. In this study, a modified glass fiber reinforced aerogel (GFRA) composite was successfully synthesized using inexpensive water glass as the raw material. Experimental results show that GFRA is significantly hydrophobic with water contact angle of 146° and low thermal conductivity of 0.018 W/(m·K). The complex network structure within the fiber mat and the high loading ratio of the aerogel contribute to the excellent thermal insulation properties of GFRA. Measurements indicate that 2.25 mm thick GFRA can maintain insulation temperature of 38.3 °C when exposed to 90 °C. Under simulated low pressure conditions in environmental chamber, with pressure of 0.06 MPa, the GFRA’s insulation temperature increased significantly, reaching 227.3 °C at approximately 400 °C. The thermogravimetric analysis confirmed the material’s excellent thermal stability, with maximum total mass loss limited to 7 % while maintaining significant hydrophobicity with water contact angle of 120.3° in high-temperature environments. GFRA’s properties demonstrate its exceptional thermal insulation capabilities, making it highly suitable for building applications.