Integration of mineral powders into SiO 2 aerogels

• Published in: Journal of non-crystalline solids Vol. 186; pp. 291 - 295
• Main Authors: Kuhn, J., Gleissner, T., Arduini-Schuster, M.C., Korder, S., Fricke, J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 1995
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/0022-3093(95)00067-4

Composites of SiO 2 aerogels and μm-sized mineral powders were produced in order to develop opacified thermally insulating materials for application at temperatures up to 1000°C. The opacification effect was observed by Fourier transform infrared spectroscopy in the wavelength from 2 to 20 μm. The albedo of the powders varied from 0.97 for solely scattering TiO 2 to 0.25 for mainly absorbing B 4C. The extinction values of the pure SiO 2 of below 1 m 2/kg in the regarded spectral range increased to about 60 m 2/kg for an ilmenite-doped sample. An increase of temperature stability of the aerogels was achieved by adding fine Al 2O 3 powder. It was demonstrated that doped SiO 2 aerogels are efficient high-temperature insulating materials.