Microstructure and performance characterization of thermal-insulating and water-resistive aerogel incorporated cement-based materials

In this work, four types of diatomite-silica aerogel incorporated composites (DSAC) with various diatomite-silica aerogel mass ratios of 1:1, 2:1, 3:1 and 4:1 were prepared by the negative pressure adsorption method. Subsequently, four groups of DSAC with different mass ratios of 0.1, 0.15, 0.2 and 0.25 were added into the cement-based matrix. Observing the morphology and microstructure of DSAC with scanning electron microscope (SEM) and pore size and specific surface area analyzer can find that diatomite and aerogel are well coupled; the characterization results of X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR) and laser confocal Raman spectroscopy (LRS) analysis prove that the DSAC is chemically stable. DSAC contribute to the improvement of thermal insulation performance and water resistance of cement-based materials, and result in a decreasing tendency of dry density and mechanical strength. The highest reduction in thermal conductivity of cement-based materials reached up to 84%.