Researchers at the University of Illinois at Urbana-Champaign have developed the next generation of self-healing material that mimics human skin by healing itself time after time. The new materials rely on embedded, three-dimensional microvascular networks that emulate biological circulatory systems.
Said Nancy Sottos, Willett Professor of materials science and engineering, "In the same manner that a cut in the skin triggers blood flow to promote healing, a crack in these new materials will trigger the flow of healing agent to repair the damage. The vascular nature of this new supply system means minor damage to the same location can be healed repeatedly."
The researchers built a scaffold using direct-write assembly, a process that employs a concentrated polymeric ink, dispensed as a continuous filament, to fabricate a 3D structure, layer by layer. Once the scaffold has been produced, it is surrounded with an epoxy resin. After curing, the resin is heated and the ink is extracted, leaving behind a substrate with a network of interlocking microchannels. A brittle epoxy coating is deposited on top of the substrate, and the network is filled with a liquid healing agent.