Self-recovering: New polymer designed to repair itself when damaged

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Defekte Scheibe (Foto: ©CIS/ http://www.pixelio.de)

Brussels — For decades scientists have dreamed of plastics that heal themselves like human skin. Inspired by the human blood clotting system, a new polymer contains a network of capillaries that deliver healing chemicals to damaged areas, according to the Plastics Portal online-magazine. Cracks in water pipes and car bonnets would seal up. Satellites could repair their own damage. Broken electronic chips in laptops and mobile phones would spontaneously sort out their own problems.

One of the first big breakthroughs came in 2001 at the University of Illinois when a team of scientists infused a polymer with microscopic capsules containing a liquid healing agent. When the material cracked, the chemicals were released and bridged the gaps.

To fix larger breakages, the team have designed a new, vascular system – inspired by the arteries and veins of the human body.  A network of channels delivers a healing agent to the site of damage. „The chemicals arrive via two separate streams. They combine to seal the gap in a two-stage reaction. Initially, they form a gel scaffold across the hole. The gel then slowly hardens into a robust, solid structure.  Regions exceeding 35mm were filled within 20 minutes, and restored mechanical function within three hours,“ said the researchers.  Tests showed the material recovered about 62 percent of its original strength.

The new material paves the way for future polymers that can recover from ballistic impacts, such as bullets, bombs or rockets.

Source: Plastics Portal