Elastic, low density epoxy/clay aerogel composites

Clay aerogels are ultra-low density materials formed by the freeze-drying of aqueous clay gels. While unmodified clay aerogels exhibit generally poor mechanical properties, incorporation of polymers into these structures can greatly increase their strengths and moduli; such polymer/clay aerogel composites have potential for use in a range of structural and insulation applications. Polymer/clay aerogel composites were formed by a new process in which water-soluble thermoset epoxy precursors are reacted within a clay hydrogel, which is then freeze-dried to produce the polymer/clay aerogel composites. The compressive properties of these polymer/clay aerogel composites greatly exceed those of plain clay aerogels; moreover, some of these composites exhibit novel elastomeric behavior, withstanding and recovering large amounts of compressive strain without failure or significant permanent deformation.