Insulating windows with silica aerogels

Silica aerogels, a newly developing type of material, also have been produced as thermal insulations with superinsulation characteristics. The nanometer-size cells limit the gas phase conduction that can take place. The aerogels are transparent to visible light, so they have potential as window insulation. The use of superinsulations at present is limited by cost and the need to have a design that protects the evacuated packets or aerogels from mechanical damage. 

Figure 4 Spectral specific extinction (absorption) of pure silica aerogel (dashed), silica aerogel doped with 5% carbon black (dotted), and RF aerogel (solid). Note that the transmission window in pure silica aerogel between 3 and 5 j4m leads to a dramatic increase in thermal radiative transport and renders pure Si02 aerogels ineffective as thermal insulators above 100°C. The integration of an opacifier markedly improves the thermal resistance of Si02 aerogels.

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