Plastic heals itself by mimicking the human body

LG made the news last year when it released a mobile phone that could self-repair minor damage to its plastic casing. While unusual, it was mostly a novelty; anything more than a shallow scratch and the damage remained.

A paper published in Science today (subscription required) details how to create plastic objects that can self-repair damage that stretches more than an inch across. An object can be damaged over and over and still repair itself without seriously compromising its strength.

The system relies on two liquids that flow into holes and cracks and form criss-crossing lines that create a gel-like scaffolding. A third material then causes the structure to harden, leaving the object repaired.

“The reactive liquids we use form a gel fairly quickly, so that as it’s released it starts to harden immediately,” study lead Scott White said in a release. “If it didn’t, the liquids would just pour out of the damaged area and you’d essentially bleed out. Because it forms a gel, it supports and retains the fluids.” 

The system works much like veins in the human body. Tubes run through a plastic material and, when it is damaged, they ooze the liquid into the area that needs repair.

The research team, which is based out of the University of Illinois, said the plastics could be used for often-damaged items like car bumpers. They could also be applied to industries where it is very difficult to make repairs, like aerospace.