When it comes to insulation, Styrofoam and other similar materials may have just met a worthy competitor, recently developed by engineers at the University of Maryland (UMD), which is much lighter, and more durable and environmentally friendly than its counterparts.
“This can insulate better than most other current insulators, including Styrofoam. It is extremely promising to be used as energy efficient building materials,” said Tian Li, a post-doctoral student at UMD.
The material, dubbed “nano-wood” by the research team, is just plain old wood stripped of lignin and hemicellulose which gives wood its characteristic brown colour and rigidity, leaving nothing but the skeletal nano-fibres of cellulose.
To rid the cell walls of lignin and hemicellulose, the researchers used nothing fancier than cheap, everyday chemicals, such as sodium hydroxide, sodium sulphite, and hydrogen peroxide (the stuff you use to bleach your hair).
The resulting material, composed of parallel strings of cellulose fibres, is extremely sturdy and effective at reflecting incoming heat, and dissipating whatever heat does manage to sneak through.
Preliminary testing revealed the material to be approximately 10 percent more efficient at blocking heat than Styrofoam and silica aerogel (considered to be the cutting edge in its class), and 30 times more durable than Styrofoam and other commercial insulators.
The additional benefits of the material being made from ordinary, recyclable wood are quite apparent – in the words of Jeff Youngblood of Purdue University in West Lafayette, Illinois, who was not involved in the research:
“This work shows that with proper treatment, wood can become stronger and more insulating than commonly used insulation, such as fiberglass for houses, with the added benefits that it is non-toxic and sustainable“.
Furthermore, the production costs of “nano-wood” are extremely low, and consist of the price of chemicals used in the process – around 7$ per square metre.
The technology is already on the way to the market through Inventwood, a UMD spinoff company set up by Liangbing Hu’s group behind the research project.
A paper detailing the new scourge of current insulation materials has been published on 9 March 2018 in the journal Science Advances.