Effect of fumed silica properties on the thermal insulation performance of fibrous compact

The particle properties play an important role in developing advanced thermal insulation board made by fumed silica. In this study, the effect of hydrophilic or hydrophobic on the thermal conductivity and fracture strength of the resultant insulation board was investigated. A higher thermal conductivity and higher strength were obtained in using hydrophilic particles. Very low thermal conductivity, below 0.02 W/m K, was achieved in using hydrophobic particles. The difference of thermal conductivity was mainly dominated by solid part. The decrease of thermal conductivity and increase of fracture strength were related to the bonding condition between particles in the boards.