Study on Properties of Coal Gangue Derived SiO_2 Aerogel and Composite Mortar

摘要

In the paper, a kind of SiO_2 aerogel based on coal gangue was synthesized and its physical properties were investigated. The properties of the composite mortar prepared with the synthesized aerogel as aggregate were further discussed. The results showed that the aerogel gained has a specific surface area of 690 m~2/g, a porosity of >90%, an average pore size of 20-50 nm, a density of 0.19 g/cm~3, and a thermal conductivity of 26.5×10~(-3) W/(m·K). The composite mortar was designed by the volume method. The performance of composite mortar with different aerogel content was studied. The results showed that the thermal conductivity, compressive strength and flexural strength of 28 days reached 0.06 W/(m·K), 3.81 MPa and 2.23 MPa, respectively.