Insulation materials, thermal glass wool

The thermal conductivities of various insulating materials are also given in Appendix A. Some typical values are 0.038 W/m °C for glass wool and 0.78 W/m °C for window glass. At high temperatures, the energy transfer through... 

Silicates of natural origin and synthetic manufacture have been used as raw materials for centuries for example, silicate glass for windows and household utensils, sand for mortar (cement), mica as an insulating material, montmorillonite as a lubricant during boring, asbestos as a thermally stable insulating material, glass wool in insulation, etc. 

Air is a unique case, as it is the only gaseous material in actual use as an insulator. Its dielectric constant is 1.0058, far less than that of any other dielectric material, and it has low thermal conductivity as well. It is particularly effective when trapped within a solid network, as in wool, cellular plastics, or glass fibers, or as an interlayer between wall panels. 

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