Elastic electric wires formed using polymer tubes filled with liquid metal
Researchers from North Carolina State University have developed elastic, self-healing wires by using liquid-metal core and the polymer sheath reconnect at the molecular level even after being severed.
“Because we’re using liquid metal, these wires have excellent conductive properties,” says Dr. Michael Dickey, an assistant professor of chemical and biomolecular engineering at NC State and co-author of a paper on the work. “And because the wires are also elastic and self-healing, they have a lot of potential for use in technologies that could be exposed to high-stress environments.”
The tiny tunnels called microfluidic channels were created and are filled with liquid-metal alloy of indium and gallium. They form liquid-metal wire in an elastic sheath. These wires can be stretched along with the polymer sheath.
Wire slicing severing makes the liquid metal to oxidize forming a “skin” that prevents it from leaking out of its sheath. The severed edges can be connected by holding the edges together, the liquid metal reconnects and the sheath re-forms its molecular bonds.
“We’re also excited about this work because it allows us to create more complex circuits and rewire existing circuits using nothing more than a pair of scissors by cutting and reconfiguring the wires so that they connect in different ways,” Dickey says.
The paper, “Self-Healing Stretchable Wires for Reconfigurable Circuit Wiring and 3D Microfluidics,” is published online in Advanced Materials. The lead author is former NC State postdoctoral research assistant Dr. Etienne Palleau. Co-authors include Stephen Reece, an undergraduate at NC State; Sharvil Desai, a former postdoctoral researcher at NC State; and Dr. Michael Smith of Arkema Inc. The research was done with support from the National Science Foundation.