Researchers have found a way to make strong, stretchable graphene oxide yarn.

The fibers were made by scientists at the Pennsylvania State University and Shinshu University in Japan. The team said that their method of creating graphene yarn can help create several practical products. For example, removing oxygen from Graphene oxide fibers could increase its conductivity. Graphene fibers with silver nanorods could make the fibers as conducive as copper fibers. Additionally, these fibers are lighter than copper, making them a potential replacement in copper transmission lines.

"The importance is that we can do almost any material, and that could open up many avenues - it's a lightweight material with multifunctional properties," said Mauricio Terrones - professor of physics, chemistry and materials science and engineering at Penn State, according to a news release.

The team made thin films of graphene by using chemicals to scrap off graphene flakes from graphite. These flakes were then mixed with water. The slurry was then concentrated by centrifugation. The resultant material was then poured over a large plate. Once the water evaporated - researchers could lift the large, transparent film off the plate. The film was then cut into narrow strips, which were then wound together using an automatic fiber scroller. The resultant fiber was strong, light and stretchable.

"We found this graphene oxide fiber was very strong, much better than other carbon fibers. We believe that pockets of air inside the fiber keep it from being brittle," said Terrones.

The study, "Super-stretchable Graphene Oxide Macroscopic Fibers with Outstanding Knotability Fabricated by Dry Film Scrolling," is published in the journal ACS Nano." It was supported by Research Center for Exotic Nanocarbons, Japan and the Center for Nanoscale Science, Penn State.

Recently, researchers from Australia and Ireland said that graphene oxide can be used to make smart clothes. These fabrics can detect chemicals and even pressure changes in the environment.