Controlling Surface Chemical States of Halloysite Aerogel for Concrete Composites with Improved Thermal Insulation

Abstract

The stability and dispersion of aerogel in concrete is the key to evaluation of the thermal insulation performance of the aerogel/concrete system. This study focuses on the structural stability of aerogel under the effect of factors such as hydrophilic concrete system, mechanical mixing, and interaction between aerogel and the concrete matrix. Stable aerogel/concrete materials were prepared by regulating and controlling kinetic parameters of the surface of halloysite (HNT) aerogels. Characterizations of the samples were investigated using techniques such as Fourier-transform infrared spectrometer, thermogravimetric analysis, N2 adsorption-desorption isotherms, scanning electron microscope, and thermal constant analyzer. The results indicated that the surfactant successfully attaches to the surface of the HNT aerogels. Aerogel particles are stable in concrete and kept their original shape. The thermal conductivity of concrete becomes lower as the content of HNT aerogels increases.