Scientists have designed a heat-insulating material made from wood that is both light and strong and made entirely from tiny, stripped-down wood fibers.
The so-called nanowood, described in the journal Science Advances, could one day be used to make more energy-efficient buildings. It's cheap and biodegradable, too.
"Nature is producing this kind of material," said senior author Liangbing Hu, a materials scientist and engineer at the University of Maryland in College Park.
Managing heat is a major issue in the cities we build. It's hard to keep heat indoors in the winter and keep it outdoors in the summer. The insulating materials currently in use are often very expensive to make, both in terms of money and of energy. They're not usually biodegradable and ultimately contribute to our growing landfills. So scientists have been trying to come up with cheaper, more environmentally friendly options.
I read about this this morning. I feel like this could be a step in a better direction for conventional building but it's really hard to say without more detail. It could be really energy intensive and use a bunch of icky stuff in making it, or it could be pretty awesome. Is there any info on the process itself?
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Looks interesting - Science Advances makes most of their (perhaps all?) published papers free to access. Here is a link to the original Nanowood Article. I'm afraid I have not had time to read through it but hopefully the full paper would answer some of the questions regarding how nanowood is produced.
Edit: Got curious and read through part of the article. Here is the section talking about how it is produced:
The nanowood is directly fabricated from natural American basswood. Note that we use American basswood as a demonstration, and that other wood species can also be used. The sample was cut along the growth direction (fig. S1). The original wood piece was treated with a mixture of NaOH and Na2SO3 heated to boiling temperatures, followed by subsequent treatment with H2O2 to remove the lignin and most of the hemicellulose from the natural wood (fig. S2) (45, 46). The wood microstructure and the hierarchal alignment are well-preserved during this process, and the sample is subsequently freeze-dried (fig. S3) (47) to preserve the nanoporous structure of the delignified wood. The weight loss and lignin content change for a 12 mm × 30 mm × 120 mm sample during the chemical process are also shown in fig. S2. The resulting nanowood is composed of mainly cellulose nanofibrils in the form of fibril aggregates. The effectiveness of lignin and hemicellulose removal is also demonstrated by high brightness of the fabricated nanowood (Figs. 1 and 2C, and figs. S1 to S3 and S7).