Abstract: A method of freeze-drying comprising rapidly freezing either liquid or supercritical carbon dioxide in and around a material having pores at a rate of at least 0.2° C./min to limit the size of crystals formed from the carbon dioxide so as to avoid the formation of gas bubbles and damage to the pores and exposure of the material to gas-liquid interfaces. During freezing a solid layer primarily of solid carbon dioxide is formed on and surrounding the material by transferring heat with a cryogenic liquid circulating about the material. This solid layer protects the material from gas-liquid interfaces and surface tension before decreasing pressure about the material by venting carbon dioxide.
Abstract: A method of producing a metal form containing dispersed aerogel particles impregnated with polymers comprising a method of impregnating an aerogel with polymers, placing the aerogel impregnated with polymers within a dissolved polymer, cooling the dissolved polymer to create a polymer form with dispersed aerogel particles impregnated with polymers, adding molten metal to the polymer form, vaporizing the polymer form, replacing the polymer form with molten metal, and cooling the molten metal to yield a metal form containing dispersed aerogel particles impregnated with polymers. Dispersing the aerogel particles impregnated with polymers within the polymer form prior to adding molten metal allows the aerogel particles to be fully dispersed throughout the metal form.