As an old adage cautions: “People who live in glass houses shouldn’t throw stones.”
Okay, great. But what if the house is actually made of see-through wood?
Although a recent breakthrough by researchers at the A. James Clark School of Engineering at the University of Maryland, College Park may not make it socially acceptable to act like an unrepentant hypocrite, it does open up the possibilities for a future in which glass has been swapped out for clear — yes, clear — wood.
The wood-goes-transparent discovery (not an entirely singular discovery but more on that in a bit) comes from a research team headed by Liangbing Hu, a materials scientist at the esteemed Mid-Atlantic research university. Hu described the
sorcery actually not-so-complicated two-step process involved with removing color molecules from a block of wood in an article recently published by the journal Advanced Materials.
“We were very surprised by how transparent it could go,” Hu admits. “This can really open applications that can potentially replace glass and some optical material.”
As detailed in the New York Times, Hu and his team first boiled a block of wood — in this case, a block of linden wood — in a solution of water, hydrogen peroxide and other chemicals for roughly two hours … and voila! During the boiling process, all traces of lingen, the aforementioned molecule that gives wood its rigidity and characteristic pulpy-brown hue, had vanished yielding a colorless block of wood.
The next step after the chemical bath?
The researchers then treated the block of transparent wood, stripped of its natural strength during the lingen-removal process, with epoxy to render it strong once again. The application of the epoxy also turned the now-white wood clear — or "mostly see-though," to be exact. In fact, the epoxy-coated wood, which kind of resembles a hunk of cloudy plastic, proved to be four to six times stronger than the untreated wood.
As the Times explains, the natural — now-transparent — channels found within wood give epoxy-treated blocks the potential to replace glass as a viable building material. “In traditional material the light gets scattered,” Hu explains. “If you have this waveguide effect with wood, more light comes into your house.”
This all said, I wouldn’t hold your breath waiting for the rise of a new era of light-strewn private homes in which the walls and windows are composed of see-though wood as the largest wood blocks to “go clear” under Hu and his team have measured 5-inches-by-5-inches. So perhaps a modest end table will come first …
And on the topic of end tables, researchers hailing from Sweden, a country that’s no stranger to the production of wooden home furnishings, have also developed a very similar two-step color-extraction and strengthening process for wood.
This project was headed by Lars Berglund of the Wallenberg Wood Science Center at the KTH Royal Institute of Technology in Stockholm. Curiously, Beglund's findings were published just weeks before those of the University of Maryland in Biomacromocules, a journal from the American Chemical Society.
Like Hu and his team, Berglund acknowledges the potential for transparent wood as an innovative, highly insulating building material that could potentially replace glass. “Wood is by far the most used bio-based material in buildings. It's attractive that the material comes from renewable sources. It also offers excellent mechanical properties, including strength, toughness, low density and low thermal conductivity.”
In addition to construction, Berglund also talked up the strengths of see-though wood in the manufacturing of solar panels. “Transparent wood is a good material for solar cells, since it's a low-cost, readily available and renewable resource," he explains. "This becomes particularly important in covering large surfaces with solar cells."
Via [NY Times]