Stability investigations of the thermal insulating performance of aerogel blanket

Abstract

Nowadays fibre reinforced silica aerogels receive special attention due to their application in the building construction sector. Aerogel, besides the Vacuum Insulation Panels are one of the so-called super/advanced/nano-technological insulation materials due to their low declared thermal conductivity. However, these days their high manufacturing cost goes against their common use. Nonetheless, the investigations of their thermal and material properties are highlighted research topics in the last few years. The testing as well as the development of these insulation materials are very important both for the manufacturers and for the designers. Therefore investigations of the thermal properties (e.g.: thermal conductivity) are extremely important. In order to show the stability of the thermal insulation performance of glass fibre reinforced aerogel blankets, firstly, moisture related investigations will be presented taking special look at the sorption isotherm and the wetting kinetic curves of the samples carried out by climatic chamber method. Then thermal conductivity measurements will be presented after humidity and thermal annealing as climatic ageing and exposures. Two types of measurement series were accomplished for thermal annealing experiments: (a) time kinetic (isothermal) investigations at 70°C for 1–42 days and (b) isochronal (1 day) annealing experiments were done, where the temperature was changed from 70°C to 210°C. After both experiment series the thermal conductivities were registered by Holometrix 2000 apparatus. The measurement results will be presented as graphs, too. Afterwards, images taken with optical microscope for exploring the changes on the surface and in the hydrophobicity of the samples will be also presented. These investigations as well as the results can serve as proof of the good thermal stability and the excellent performance of this insulation.