To make the material, the researchers took wood and stripped away two of its natural components -- lignin, which makes it brown and rigid, and hemicellulose. That turned the wood white and made it less able to conduct heat. The tubed structures within a tree that transport water and nutrients up the trunk run in one direction, and heat can conduct along those channels. But heat doesn't conduct across those channels very well and because stripping away the lignin and hemicellulose leaves a lot of gaps in the wood, wood treated to become nanowood conducts heat in that direction even less.
Along with insulating more effectively than currently used materials like Styrofoam, nanowood is also stronger, and it won't cause the same lung irritations that fibers from glass wool insulators do. The research team also says that it could be fabricated for as low as $7.44 per square meter, can be folded and rolled when less than one millimeter thick and is biodegradable, so it won't add to landfill waste like the insulating materials we often use now do.
"My research program experiments with nature's nanotechnology that we see in wood," project head Liangbing Hu, an associate professor in the department of materials science and engineering at the University of Maryland, said in a statement. "We are reinventing ways to use wood that could be useful in constructing energy efficient and environmentally friendly homes." The work was recently published in Science Advances.