Who hasn't walked to their car after getting groceries or the like and suddenly found a nice, large scratch where you're fairly sure there wasn't one before? Then you think do you spend $50 on some random infomercial product claiming to fix scratches of every color, get the thing repainted, or just live with it? In my case, of course, the third is the obvious option. What can I say? I'm cheap, and my car is instantly recognizable for its terrible paint job (let me tell you, black + Florida weather = bad idea).
But what if my car's paint could fix itself? That would be worth dropping a huge wad of cash on. And it turns out that scientists aren't too far off from a self-healing paint. And the best part? All it would require to heal itself is sunlight.
A study, published in Science, shows that scientists are just a step or two away from creating the magical paint. The researchers started with polyurethane - a major consituent of current paints and other high-performance materials. They then added an oxetane-substituted chitosan, a compound similar to the chitin which makes up the exoskeleton of arthropods like lobsters and crabs. When the special compound mix is scratched, the oxetane, which is a ring, is broken. If ultraviolet light then strikes the mix, the chitosan is stimulated to bond with the broken ring, eventually dragging the two sides back together, thus eliminating the scratch. The image to the right shows photos of the process in action. The whole process, according to the researchers, could take as little as an hour to completely fix minor scratches.
The special reaction between the oxetane and the chitosan only occurs where the paint is damaged, so it won't be changing the look of the paint in any other ways. The scientists are hopeful that a film like the one they tested could one day be used for a variety of uses, adding pigment to create car paint just being one of them. Of course, more testing and tweaking is required before the products could be marketed. Also, because its a derivative of chitin, it's quite green compared to other paints.
*sigh* Since they obviously will need people to test out these products, I guess I could be kind enough to do my part and subject my poor abused car to being a test subject. It could REALLY use a new paint job... just ask anyone whose seen it. It's not a pretty sight.
Ghosh, B., & Urban, M. (2009). Self-Repairing Oxetane-Substituted Chitosan Polyurethane Networks Science, 323 (5920), 1458-1460 DOI: 10.1126/science.1167391