New Self-Repairing Plastic Material Invented at Stanford

Linda A. Cicero/Stanford News

The latest invention from Stanford University's Department of Electrical Engineering sounds like something a superhero would have. A self-repairing plastic-metal material has been developed by a team of professors, researchers and graduate students.

This is the first material of its kind that can sense pressure and heal itself when burned, torn or cut - a little bit like human skin. The Stanford researchers report on their "flexible and electrically conducting material" in the journal Nature Nanotechnology.

Stanford Chemical Engineering Professor Zhenan Bao said the researchers combined self-healing ability of a plastic polymer and the conductivity of a metal to get what Bao called "the best of both worlds." The material, according to Stanford University News, took six months to develop.

"If you take a piece of cardboard, for example," graduate student Benjamin Tee said, "and you cut it into two, if you have this material, it brings the two pieces together to attach the two sides to each other without a need for glue - it does it itself. That is the magic."

During the development process, Bao told Stanford University News, "the researchers took a thin strip of the material and cut it in half with a scalpel. After gently pressing the pieces together for a few seconds, they found the material regained 75 percent of its original strength and electrical conductivity. The material was restored close to 100 percent in about 30 minutes."

"Even human skin takes days to heal. So I think this is quite cool," Tee said.

Tee suggested some ways this invention might be useful in the next few years. For example, if the material were to cover electronic devices such as phones and tablets, they might be made impervious to scratches or nicks.

It would only take "several minutes" for them to fix themselves, said Tee.

For bigger damage that the material is unable to repair on its own, Tee said that phones could be programmed to notify their owners of damage if they were unaware of it.

The Air Force Office of Scientific Research, which assisted in the funding of this research, said it hopes to put this material to good use in the field of prostheses.

Ideally, users would quickly be able to heal exterior damage make to their prosthetic legs or arms with the help of this new material.

Tee admitted that the material cannot heal interior damage, such as that done by gunshots or fire that might penetrate the material. "There are definitely some limits to how much the damage can be," said Tee. At least for now.