Researchers in California may have designed a synthetic version—a flexible, electrically conductive, self-healing polymer.
The result is part of a decadelong miniboom in “epidermal electronics”—the production of circuits thin and flexible enough to be attached to skin (for use as wearable heart rate monitors, for example) or to provide skinlike touch sensitivity to prosthetic limbs. The problem is that silicon, the base material of the electronics industry, is brittle. So various research groups have investigated different ways to produce flexible electronic sensors.
Chemists, meanwhile, have become increasingly interested in “self-healing” polymers. This sounds like science fiction, but several research groups have produced plastics that can join their cut edges together when scientists heat them, shine a light on them, or even just hold the cut edges together.
To demonstrate that both the mechanical and the electrical properties of the material could be repeatedly restored to their original values after the material had been damaged and healed, the researchers cut the polymer completely through with a scalpel. After pressing the cut edges together gently for 15 seconds, the researchers found the sample went on to regain 98% of its original conductivity. And crucially, just like the ESPCI group’s rubber compound, the Stanford team’s polymer could be cut and healed over and over again.
"I think it’s kind of a breakthrough," says John J. Boland, a chemist at the CRANN nanoscience institute at Trinity College Dublin. "It’s the first time that we’ve seen this combination of both mechanical and electrical self-healing."
Definitely worth the short read.