Researchers at the University of Southern Mississippi have developed an injection moldable copolymer which they say can mimic the human skin’s ability to heal scratches, offering the potential of providing cell phones, laptops, cars and other products with self-repairing surfaces.
The copolymer changes color to warn of wounds and then heal itself when exposed to light, according to a paper presented at the 243rd National Meeting & Exposition of the American Chemical Society (ACS), the world’s largest scientific society.
“Mother Nature has endowed all kinds of biological systems with the ability to repair themselves,” says Professor Marek W. Urban, who reported on the research. “Some we can see, like the skin healing and new bark forming in cuts on a tree trunk. Some are invisible, but help keep us alive and healthy, like the self-repair system that DNA uses to fix genetic damage to genes. Our new plastic tries to mimic nature, issuing a red signal when damaged and then renewing itself when exposed to visible light, temperature or pH changes.”
He says that scratches in automobile fenders might be repaired by exposing the fender to intense light. Critical structural parts in aircraft might warn of damage by turning red along cracks so that engineers could decide whether to shine the light and heal the damage or undertake a complete replacement of the component.
Urban was reluctant to release to The Molding Blog many technical details, including even the types of plastic in the copolymer. He revealed this much to the ACS: The new copolymer has small molecular links that span the long chains that make a material a plastic. When the copolymer is scratched or cracked, these links break and change shape. He also said that the process for producing the plastic is water-based, “rather than relying on potentially toxic ingredients”. Research funding was provided by the U. S. Department of Defense.
He also told The Molding Blog via email: “This is (a) copolymer that can be injection moldable if designed properly, obtain(ed) by emulsion polymerization process and inexpensive.”
New plastics turn red when damaged, then heal themselves when exposed to light. Credit: Marek W. Urban
