Self-Healing Plastics A Positive And Attractive Advancement
Hard at work on making the impossible happen, scientists at Fraunhofer in Germany are developing a viable way for plastics to heal themselves over time.
Everything breaks, usually at a moment that is most inopportune. Tires blow out, windows shatter and plastic objects of every kind and description crack and snap at the most inconvenient of times. Thanks to the rigidity of most plastic material, once a crack has started, stopping it is impossible and it is inevitable that the object will eventually break and be rendered useless.
Typically, this breaking process starts long before we can see it with the naked eye, in the form of micro-cracks in the plastic's surface. These cracks spread and spiderweb and eventually lead to the familiar snapping of all our plastic pieces.
Using nature as their inspiration and focusing on those plants which feature the capsulated protein hevein to repair damage done to them, the Fraunhofer team has devised a way to help man-made structures repair themselves after they have been damaged.
Initially, the team used microcapsules filled with the healing agent polyisobutylene and placed them into an elastomer filled with synthetic plant material to simulate the healing process. The idea was that just as in nature the capsules would break when a crack appeared and spread their healing magic, but this proved ineffective. Placing the healing agent directly into the elastomer yielded better results, but the best method divined by the team was to charge the elastomers with ions in order to produce an attractive effect when the crack occurred and encourage the hevein particles to get together and spread the love.
While plastics using this method saw a significant reduction in microcracking even over as little as 30 minutes, it is important to note that this form of self-healing still required interference from an outside source, as the elastomers could not be automatically charged.
Still, the results are promising, as so many of our devices make the transition from wood or metal to plastic and we seem to get more aggressive with them by the day. We have confidence in progress, though - these Fraunhofer fellows and fraus seem to know what they're doing.