Experimental Mechanics

, Volume 49, Issue 5, pp 707–717 | Cite as

Characterization of Microvascular-Based Self-healing Coatings

  • K. S. Toohey
  • N. R. Sottos
  • S. R. White


A protocol is described to assess self-healing of crack damage in a polymer coating deposited on a substrate containing a microvascular network. The bio-inspired coating/substrate design delivers healing agent to cracks in the coating via a three-dimensional microvascular network embedded in the substrate. Through capillary action, monomer flows from the network channels into the crack plane where it is polymerized by a catalyst embedded in the coating. The healing efficiency of this materials system is assessed by the recovery of coating fracture toughness in a four-point beam bending experiment. Healing results for the microvascular networks are compared to data for a coating containing microencapsulated healing agents. A single crack in a brittle epoxy coating is healed as many as seven times in the microvascular systems, whereas microcapsule-based healing occurs for only one cycle. The ability to heal continuously with the microvascular networks is limited by the availability of catalyst in the coating.


Self-healing Coating Microvascular Substrate Fracture toughness Autonomic 



This work was funded by the Air Force Office of Scientific Research Multidisciplinary University Research Initiative (Grant # F49550-05-1-0346), and the Beckman Institute for Advanced Science and Technology Graduate Fellows Program.


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Copyright information

© Society for Experimental Mechanics 2008

Authors and Affiliations

  1. 1.University of Illinois at Urbana-ChampaignChampaignUSA

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