High-Performance Insulation or Superinsulation The Basics

Range of Thermal Conductivity Vaiues and the Physics of Heat Transport 

Organic aerogels Aerogels derived from organic compounds 0.012-0.020 

Vacuum insulation Silica core sealed and evacuated 0.003-0.01 C 

Vacuum glazing (VG) Double glazing unit with evacuated space 0.0001-0.0005  

VIP and VG offer outstanding thermal resistance because evacuation of the porous core material or the glazing cavity, respectively, results in a drastic reduction of heat transport by gas molecules. Aerogels on the contrary are nonevacuated superinsulators. Their low thermal conductivity is correlated with the pore structure of these materials. Before we briefly touch on the effect of the unique structural features of aerogels on heat transport, let us recapitulate the basics. Generally, heat is transferred by conduction, convection, and radiation. In porous materials there are five possible contributions to the total heat transfer, namely  

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