Transparent crab shell holds the secret to bendable screens
By Mark Brown, wired.co.uk
| Published 20 minutes ago
Biologists from Kyoto University in Japan have turned a crab's shell transparent. More than just a neat party trick, the research into see-through structures could help the construction of flat panel displays, solar cells and bendy screens.
Muhammad Iftekhar Shams and his team at Kyoto University took an entire (dead) crab, and treated its body to a brew of acids and chemicals. Hydrochloric acid, sodium hydroxide and ethanol stripped the body of minerals, proteins, lipids, fats and pigments.
This left a crab shell made entirely of translucent chitin. Chitin is a long-chain polymer that is the main component of crustacean exoskeletons.
Finally, the shell was immersed in an acrylic resin monomer. Polymerisation kicked in (monomer molecules react together to form polymer chains), and the team ended up with a perfect, ghostly recreation of a crab, only now completely see-through.
Buoyed by their success, Shams and colleagues crushed up chitin from crab shells and spread the powdered material into a nanocomposite sheet. Then, much like the crab body, the paper-like sheet was given the acrylic resin monomer treatment, leading to an optically transparent panel.
The material is exciting because it doesn't expand or lose its stability when heated—in fact, it's ten times as resistant to heat as traditional materials such as glass-fiber epoxies. This makes it a potential material for building bendable screens or solar cells that are moulded into shapes. It has a high light transmittance too.
"This class of materials is an interesting candidate for transparent substrates in next-generation electronic devices such as flexible displays and solar cells," the team writes in the paper's abstract—published by the Royal Society of Chemistry.
Better still is that chitin—the secret ingredient—is abundant in nature. Not only is it found in the shells of crabs, lobsters and shrimps, this adaptable natural material also shows up in the cell walls of fungi, the exoskeletons of arthropods and insects, the tongue-like radulas of mollusks, and the beaks of cephalopods.
Image courtesy of Royal Society of Chemistry/Kyoto University