The smart type of plastic, which automatically knits together when cracked or broken, could one day be used to make artificial organs.
The material contains microcapsules filled with a special healing agent.
Like human skin, it bleeds and heals itself, offering a potential breakthrough in vital materials used in surgical implants. It could also prove useful for making rocket and spacecraft components, which cannot be repaired once they are in use.
Wear and tear
Plastics are normally susceptible to cracking caused by vibration, bending, and heat. Often the damage is deep within a structure, where it is difficult to detect and repair.
But in fracture tests, the new self-healing plastic regained 75% of its original strength.
Scott White, a member of the University of Illinois team that developed the "skin", said: "When the material cracks, the microcapsules rupture and release the healing agent into the damaged region through capillary action."
The scientists are now trying to modify the plastic so that it is suitable for commercial use.
They believe the technology could revolutionise the plastics industry, with satellites, rocket motors and prosthetic organs prime candidates for treatment.
The research is reported in the journal Nature.