Cars Will Heal Their Own Scratches and Scrapes
The key ingredient of the new material created by polymer scientist Marek Urban and his doctoral student Biswajit Ghosh is a dash of a precursor to chitosan, a structural element in the shells of crabs, shrimp, insects and fungi. To the chitosan precursor, the scientists added oxetane, a ringed molecule that can be broken without much energy. Then they incorporated this new OXE-CHI molecule into polyurethane, the material that might need repair.Several approaches have been taken to self-healing materials, and as humans begin to colonise more treacherous environments -- such as outer space, the sea bottom, the open seas, and polar environments -- it will become more important for their habitats and transport vehicles to be able to heal any breaches, perforations, or structural fatigue.
Scratching the new material breaks the oxetane rings, exposing a reactive end hungry to bind to something, explains Urban, of the University of Southern Mississippi in Hattiesburg. UV light then cleaves the chitosan component, which in turn binds to the reactive ends made by the scratch.
Test scratches made with a razor blade healed after less than an hour of exposure to a 120 watt florescent UV lamp, a little more power than you’d get from sitting in the sun, the researchers report. _ScienceNews
Our brave new future of rising hazard requires better materials. Anything less would be uncivilised.
Labels: materials science