An Electrically and Mechanically Self-Healing Composite With Pressure- And Flexion-Sensitive Properties for Electronic Skin Applications

Nat Nanotechnol. 2012 Dec;7(12):825-32. doi: 10.1038/nnano.2012.192. Epub 2012 Nov 11.

Abstract

Pressure sensitivity and mechanical self-healing are two vital functions of the human skin. A flexible and electrically conducting material that can sense mechanical forces and yet be able to self-heal repeatably can be of use in emerging fields such as soft robotics and biomimetic prostheses, but combining all these properties together remains a challenging task. Here, we describe a composite material composed of a supramolecular organic polymer with embedded nickel nanostructured microparticles, which shows mechanical and electrical self-healing properties at ambient conditions. We also show that our material is pressure- and flexion-sensitive, and therefore suitable for electronic skin applications. The electrical conductivity can be tuned by varying the amount of nickel particles and can reach values as high as 40 S cm(-1). On rupture, the initial conductivity is repeatably restored with ∼90% efficiency after 15 s healing time, and the mechanical properties are completely restored after ∼10 min. The composite resistance varies inversely with applied flexion and tactile forces. These results demonstrate that natural skin's repeatable self-healing capability can be mimicked in conductive and piezoresistive materials, thus potentially expanding the scope of applications of current electronic skin systems.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Biomimetics / methods
  • Electric Conductivity
  • Molecular Structure
  • Nanotechnology / methods
  • Polymers / chemistry*
  • Pressure*
  • Skin / chemistry*
  • Surface Properties
  • Wound Healing / drug effects*

Substances

  • Polymers