Property Changes of SiO2 Aerogel on Insulation Performance under Different Time and High Temperature Condition

To study the impacts of structural change of SiO2 aerogel on its insulating properties, the samples were treated in long time (0-12h) at 500°C, 600°C, 700°C and 800°C. The results show that with the time increased, the shrink extends in thickness, the weight loss and the density is basically unchanged under the 500°Cand 600°C. As for 700°C and 800°C, the results were treated with 0-12h, the shrink extends in thickness, the weight loss and density increases considerably. Besides, the structure and composition of SiO2 aerogel after the different temperature treaded with 0.5h were tested. The results show that when the heat treatment temperature is between 200-800°C, the small pores in SiO2 aerogel collapses and large pores increase, and the density is stil1 able to maintain the 1ow value due to the unbroken skeleton. When the heat temperature is between 800-1000°C, the secondary particle size increases and the rnutual integration of the secondary particles occurs, the density will be significantly increased.