Novel multifunctional aerogel materials from synergy of additive manufacturing and sol-gel processing

Many highly porous materials with pore volumes greater than 90% are attractive due to their high specific surface area and tunable surface energy. These materials cannot be easily adopted in advanced applications due to their poor mechanical strength and low handling stress. The advent of 3D-printing methods comes handy in such cases. The porous materials can be 3D-printed directly as metamaterials that offer much higher elongation and compliance in response to extensional stress than the parent porous materials themselves. The porous materials can also be made an integral part of 3D-printed, load bearing scaffolds to take advantage of their multi-functional attributes in thermal insulation, liquid-liquid separation, and nanoparticle removal from air with performance close to those of HEPA filters. This talk will illustrate three such examples. In one example, polyurethane aerogel metamaterials show substantially high elongation due to strategic arrangements of the highly porous limbs. In the second example, high porosity polyimide domains are grown inside or on surfaces of solid polymer scaffolds to produce excellent thermal insulation or provide efficient removal of noxious dye molecules from aqueous streams. In last example, variable surface energy strands of syndiotactic polystyrene or polyimide are used in removing water droplets from a hydrocarbon oil. Some generalizations will be made that other researchers can use and expand the concepts presented in this talk to an array of materials systems.