Regenerative and Remodeling Systems
Our group is pioneering the development of new synthetic material systems that mimic the regenerative and remodeling capabilities of biological systems. Regenerative materials build on our existing self-healing concepts, but address large scale damage in which significant mass loss is apparent (e.g. ballistic impact). We are developing materials that not only heal, but also regrow in response to a damage event. Remodeling materials have the capability to modulate their properties in response to environmental stimuli. By implementing features of regeneration and remodeling, we shift from a strategy of overdesign to damage management and mechanical homeostasis.
Regeneration: Nature's ability to recover and respond to damage or other environmental stimuli is unmatched in synthetic systems. Our aim is to replicate some of the key regenerative features in biology and apply them to synthetic materials. We are developing multifunctional materials that are capable of regenerating (regrowing) material when significant mass loss occurs in order to recover lost functionality. These materials require new strategies to achieve repeatable recovery and autonomous response to damage. The key challenge to this approach is the transport of active fluids that can undergo transformation from low viscosity fluids to high strength (polymeric) structural materials.
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| Impact damage in epoxy regenerated using a bi-stage restorative chemistry. Dual vascular channels deliver the isolated components of the bi-stage chemistry to the site of impact damage. Mixing of the fluidic components leads to gelation and in situ generation of a scaffold network. Subsequent polymerization of the monomer component leads to recovery of structural properties. Ref: White et al. Science, 2014. | Photo-polymerized acrylate coating being regenerated via release of monomer and photo-initiator from vascular substrate after coating removal. Photo-blocking compounds are incorporated into the substrate material to preserve chemical reactivity of the monomer reservoir. Ref: Gergely et al. Proceedings of the Fourth International Conference on Self-Healing Materials, June 16-20, 2013, Ghent, Belgium. 1. R. Gergely , W. Turchyn , B.P. Krull J.S. Moore , N.R. Sottos and S.R. White, Regenerative Polymeric Coatings, Conference proceedings of the Fourth International Conference on Self-Healing Materials, June 16, 20, 2013, Ghent, Belgium. |
Central excised hole in an epoxy substrate being filled and regenerated during active pumping of bi-stage regenerative chemistry through dual vascular networks. Ref. White et al. Science, 2014. |
Remodeling: Our strategy is to develop materials that can perpetually manage damage to achieve a state of mechanical stasis. Older or damaged material is continually replaced with new material on a periodic basis via vascular circulation. We are inspired by biology (e.g. bone) in which remodeling achieves replacement of materials in response to various environmental stimuli including mechanical stress.