Preparation and characterization of aerogel/expanded perlite composite as building thermal insulation material

Aerogel was a potential substitute for the traditional thermal insulation materials. But aerogel's fragility and high prices have negative effects on the mechanical property and cost of aerogel-based building thermal insulation materials. To solve this problem, a novel thermal insulation composite aerogel/expanded perlite (AEP) was prepared by filling the aerogel into porous structure of expanded perlite (EP). The aerogel in the pores of AEP would be protected by solid skeleton of AEP, and also reduce the thermal conductivity of AEP. The AEP was characterized by X-Ray diffraction, Fourier transformation infrared, digital microscope, scanning electron microscope, N2 adsorption-desorption isotherms and transient hot-wire method. The results reveal that aerogel could be effectively distributed in porous structure of EP and has a positive effect on the pore structure and thermal insulation performance of EP. AEP has typical mesoporous structure and shows chemical stability and hydrophobicity. The mesoporous volumes and BET specific surface areas of AEP were about 100-280 times and 50-150 times as large as those of EP, respectively. And thermal conductivities of AEP were decreased by 14.7-31.8% than EP. All results suggested that AEP can be considered as potential building thermal insulation materials due to good thermal insulation performance and lower cost.