Stanford University announced Monday that a team of chemists and engineers created a flexible, self-healing, conductive material. Led by chemical engineering professor Zhenan Bao, the researchers combined a plastic consisting of chains of molecules joined by hydrogen bonds, with rough nanoparticles of nickel that one of the researchers, Benjamin Chee-Keong Tee, describes as mini-machetes. The bumpy edges, Tee said, concentrate the electrical field and make it easier for current to flow from one particle to the next. Twisting or pressing on the material changes the distance between the metal particles and therefore the resistance; such changes can be translated to measurements of pressure.
When sliced with a scalpel and then pressed back together, the material recovers 75 percent of its mechanical strength and electrical conductivity in seconds; 100 percent in about half an hour.
The team envisions prosthetic arms that can detect the pressure of a handshake or the degree of bend in a joint, as well as electrical wires that can repair themselves when broken.
Caption: A researcher cuts a piece of the self-healing "skin". Photo: Stanford University.