What is self-healing plastic skin?

The future of skin? Hemera
The future of skin? Hemera

Skin is pretty amazing stuff. It protects us. It repairs itself when injured. Oh yeah, and it serves as one of our primary ways of experiencing the world around us -- everything from sensing a slight chill in the air to feeling the warmth and pressure of a loved ones' embrace.

So whether you're contemplating the future of prosthetic limbs or some sort of humanoid robot lover, we always come back to the flesh. In fictional settings, we often skip over advanced synthetic skin. I never got the impression that we'd want to caress Commander Data's weird face. Likewise, the Terminator films and ancient Irish legend both skip ahead to the notion of growing real flesh grown over metallic limbs -- and, indeed, such cybernetic visions are inspiring. But in the shorter term, we'll need synthetic skin that can rival the genuine article. And even in the long term, I can easily imagine situations where advanced synthetic skin would be preferable to organics.

Luckily, we're seeing some pretty amazing stuff out of from Stanford Chemical Engineering Professor Zhenan Bao and her team. They recently succeeded in making the first synthetic skin material capable of subtle pressure sensation and self-healing. According to Stanford News, previous attempts at self-healing materials could only heal once and/or required high temperatures to do so.

Bao's skin material consists of a polymer made from long chains of molecules joined by hydrogen bonds. So it's bendable, but the bonds reorganize and restore the structure when broken. Next, the researchers added particles of nickle to make the stuff an excellent conductor of electricity. When they injured the material in a test, they found that it restored nearly 100 percent of its mechanical strength and electric conductivity in 30 minutes. They cut it again in the same place 50 times in a row, just to see how it fared. The skin repaired itself effectively each time.

And how does feeling work in this synthetic skin? Well those nickle particles conduct an electric current. Even the pressure of a handshake alters the distance between those embedded particles, which could be computed into a sensation of touch.

So the Bao is interested in how this material might improve prosthetic limbs, but she also envisions a day when the remarkable substance fills the walls of our buildings and coats our personal computing gadgets.

What if your smart phones could feel you back? What if the walls of your house ached during an earthquake?

About the Author: Robert Lamb spent his childhood reading books and staring into the woods — first in Newfoundland, Canada and then in rural Tennessee. There was also a long stretch in which he was terrified of alien abduction. He earned a degree in creative writing. He taught high school and then attended journalism school. He wrote for the smallest of small-town newspapers before finally becoming a full-time science writer and podcaster. He’s currently a senior writer at HowStuffWorks and has co-hosted the science podcast Stuff to Blow Your Mind since its inception in 2010. In his spare time, he enjoys traveling with his wife Bonnie, discussing dinosaurs with his son Bastian and crafting the occasional work of fiction.