Effect of glass fiber on the mechanical and thermal insulation performances of kaolinite-based thermal insulator

The development of high-performance thermal insulators is essential for achieving building energy efficiency. The mechanical properties of traditional inorganic porous thermal insulators are not ideal enough. Among various inorganic fiber materials, glass fiber is widely recognized as the most cost-effective option and is expected to significantly enhance the mechanical performance of inorganic porous thermal insulators. The present study employed kaolinite and water glass as primary raw materials, with the addition of glass fiber as a reinforcing material. By means of the chemical foaming method, a kaolinite-based thermal insulator was prepared. The impact of glass fiber on the physicochemical properties of insulator was investigated. The results revealed that the samples containing 15 wt% glass fiber exhibited compressive strength of 1.06 MPa and thermal conductivity of 0.075 W/(m·K), while achieving a remarkable strength-to-density ratio of 4.36. After undergoing heat treatment, the samples exhibited enhanced thermal insulation performance with a reduction in thermal conductivity by approximately 34.2 %. However, the compressive strength showed a significant decline. The samples showcased exceptional thermal insulation capabilities in a simulated high-temperature outdoor environment. • Mechanical properties of glass fiber reinforced porous thermal insulation material are studied. • Effect of heat treatment on glass fiber and porous thermal insulation material was analyzed. • Thermal insulation performance under simulated high temperature environment was evaluated.