Nanoporous thermal insulation materials prepared with fumed SiO2 possess excellent thermal insulation property, and have been attracted much attention, but their mechanical properties are poor. Adding a small amount of fiber materials as a toughening material can improve the mechanical properties of the nanoporous thermal insulation materials. However, too much fiber materials additives will seriously affect the thermal insulation property. In this study, SiO2-based nanoporous thermal insulation materials were prepared, and the effects of addition amounts of xonotlite and forming pressure on the mechanical performance and thermal insulation performance of as-prepared thermal insulation materials were investigated. It was found that addition of 10% xonotlite and forming pressure of 2MPa were proper for the preparation of SiO2-based nanoporous thermal insulation materials. The compressive strength and thermal conductivity of as-prepared materials were 0.34 MPa and 0.031 W·m−1·K−1, respectively.

Keywords: Xonotlite; Nanoporous Insulation Materials; Fumed SiO2; Compressive Strength; Thermal Insulation Property.