Letter | Published:

Self-healing materials with microvascular networks

Nature Materials volume 6, pages 581585 (2007) | Download Citation

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Abstract

Self-healing polymers composed of microencapsulated healing agents exhibit remarkable mechanical performance and regenerative ability1,2,3, but are limited to autonomic repair of a single damage event in a given location. Self-healing is triggered by crack-induced rupture of the embedded capsules; thus, once a localized region is depleted of healing agent, further repair is precluded. Re-mendable polymers4,5 can achieve multiple healing cycles, but require external intervention in the form of heat treatment and applied pressure. Here, we report a self-healing system capable of autonomously repairing repeated damage events. Our bio-inspired coating–substrate design delivers healing agent to cracks in a polymer coating via a three-dimensional microvascular network6 embedded in the substrate. Crack damage in the epoxy coating is healed repeatedly. This approach opens new avenues for continuous delivery of healing agents for self-repair as well as other active species for additional functionality.

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Acknowledgements

This work has been financially supported by the Air Force Office of Scientific Research Multidisciplinary University Research Initiative (grant number F49550-05-1-0346). K.S.T. is supported in part by the Beckman Institute for Advanced Science and Technology Graduate Fellows Program. We extend our gratitude to the Imaging Technology Group at the Beckman Institute, especially S. Robinson, for assistance with scanning electron microscopy.

Author information

Affiliations

  1. Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA

    • Kathleen S. Toohey
  2. Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA

    • Kathleen S. Toohey
    • , Nancy R. Sottos
    • , Jennifer A. Lewis
    • , Jeffrey S. Moore
    •  & Scott R. White
  3. Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA

    • Nancy R. Sottos
    •  & Jennifer A. Lewis
  4. Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA

    • Jeffrey S. Moore
  5. Department of Aerospace Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA

    • Scott R. White

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Contributions

K.S.T. carried out all of the experiments and analysis. N.R.S. and S.R.W. conceived the microvascular substrate–coating experiment and directed the research. J.A.L. and S.R.W. developed the direct-write manufacturing method. J.S.M. assisted with the healing chemistry. All authors participated in discussions of the research and wrote the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Nancy R. Sottos.

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    Supplementary Information

    Supplementary information, scheme 1 and figures S1-S3

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DOI

https://doi.org/10.1038/nmat1934

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