Wires created that can stretch 8 times their original length

21 Dec 2012

Conductive wires have been developed by researchers from North Carolina State University that can be stretched up to eight times their original length while still functioning. The wires are suitable for use in a wide variety of consumer electronics, and may potentially be useful in future electronic textiles.

The wires are created by creating a thin tube from an elastic polymer, which is then filled with a conductive liquid metal alloy of gallium and indium.

"Previous efforts to create stretchable wires focus on embedding metals or other electrical conductors in elastic polymers, but that creates a trade-off," says Dr. Michael Dickey, an assistant professor of chemical and biomolecular engineering at North Carolina State University and co-author of a paper on the research.

"Increasing the amount of metal improves the conductivity of the composite, but diminishes its elasticity," Dickey says. "Our approach keeps the materials separate, so you have maximum conductivity without impairing elasticity. In short, our wires are orders of magnitude more stretchable than the most conductive wires, and at least an order of magnitude more conductive than the most stretchable wires currently in the literature."

Even though the manufacture of these wires is relatively simple, the fact that they leak if severed is an issue that needs to be resolved before this new technology becomes available commercially. The researchers are now addressing ways to minimise this leakage.

The research was funded by a National Science Foundation (NSF) CAREER award and the NSF's Research Triangle Materials Research Science & Engineering Center.

Further information
Researchers Use Liquid Metal to Create Wires That Stretch Eight Times Their Original Length