A new plastic that bleeds and heals like human skin was demonstrated to the American Chemical Society this week. The plastic turns red when it becomes damaged, then repairs itself if exposed to light or temperature changes, with the color fading away as it heals itself.
and colleagues at the University of Southern Mississippi in
Hattiesburg were inspired to create their self-healing plastic by signs
of healing in nature such as newly formed tree bark.
Earlier self-healing materials
do not change colour and require focused laser light for repairs. This
new material turns red when damaged and repairs itself when exposed to
visible light or changes in temperature or pH. It can also fix itself
multiple times, unlike previous materials.
New plastics turn red when damaged, then heal
themselves when exposed to light.
Credit: Prof. Marek W. Urban, Ph.D.
“Mother Nature has endowed all kinds of biological systems with the
ability to repair themselves,” explained Professor Marek W. Urban,
Ph.D., 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
Urban, who is with the University of Southern Mississippi in
Hattiesburg foresees a wide range of potential applications for plastic
with warn-and-self-repair capabilities. Scratches in automobile fenders,
for instance, might be repaired by simply 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. And there could be a range of applications
in battlefield weapons systems.
Unlike other self-healing materials, this plastic’s healing process
can work over and over, he added. It could serve a variety of purposes,
from things like nail polish to self-healing car fenders to airplanes.
It would improve safety by drawing attention to a structural defect, and
it could repair minor defects in the presence of intense light.
“Where degradation occurs or [there is] mechanical damage, the color would start to change,” Urban said.