US Scientists develop new self-healing material

Researchers from Penn State University in the US have developed a new self-healing material with potentially wide-ranging applications.

The material can be broken, and then repaired through the application of a few drops of water and a small amount of heat.

Detailed in the latest edition of Scientific Reports, the material is a high-tech multi-phase polymer of considerable strength.

“What’s unique about this plastic is the ability to stick itself back together with a drop of water,” said Melik Demirel, professor of engineering science and mechanics, Penn State.

“There are other materials that are self healing, but not with water.”

Specifically, a small dog-bone shaped sample of the polymer was manufactured and then cut in half. After being exposed to water at 113º F (45 º C) and pressure applied by a metal tool, the two halves reformed back into the dog-bone shape.

Importantly, the material was found to retain similar levels of strength after healing its structure.

The researchers who developed this material were investigating compounds found within the teeth of several different species of squid. There they made the discovery that self-healing proteins were ubiquitous across these species around the world.

Despite this, due to the low amount of these proteins contained within a single squid, the researchers had to find an alternative source for this protein, so as not to deplete global populations of the animals.

As a solution, the Penn State researchers used biotechnology to create the proteins within bacteria. These can then either be moulded using heat or cast by solvent evaporation.

The research team believes that their material could have a number of potential applications in areas where objects are difficult or costly to repair.

“If one of the fiber-optic cables under the ocean breaks, the only way to fix it is to replace it,” said Demirel. “With this material, it would be possible to heal the cable and go on with operation, saving time and money.

In addition, they believe the self-healing material could also be used by the biotech industry.

“Maybe someday we could apply this approach to healing of wounds or other applications,” he said. “It would be interesting in the long run to see if we could promote wound healing this way.”