Ancient Building Techniques Inspire Wood That You Can See Through

A wooden smartphone screen might sound like science fiction, but researchers at Kennesaw State University have created a semi-transparent wood using surprisingly simple, natural ingredients – including egg whites and sticky rice that harken back to ancient building practices.

Presented at the American Chemical Society spring meeting in San Diego this week, the innovation tackles a pressing environmental problem: the overwhelming prevalence of non-biodegradable plastics in modern electronics and building materials.

“In the modern day, plastic is everywhere, including our devices that we carry around. And it’s a problem when we reach the end of that device’s life. It’s not biodegradable,” explained Bharat Baruah, a chemistry professor at Kennesaw State University who led the research.

The concept of transparent wood isn’t entirely new – scientists have been exploring it as a plastic alternative for years. But previous versions typically incorporated synthetic materials like epoxies to maintain structural integrity. Baruah’s approach is different, drawing inspiration from his personal background.

Growing up in northeastern India’s state of Assam, Baruah observed centuries-old buildings constructed long before modern cement existed. The ancient masons used a surprisingly effective mixture of sand, sticky rice, and egg whites as binding agents. This traditional knowledge sparked the idea for his natural transparent wood.

Creating the material involves a multi-step process that transforms ordinary wood into something extraordinary. The team first removes lignin and hemicellulose – two of wood’s three main components – using chemicals including sodium sulfite, sodium hydroxide, and diluted bleach in a vacuum chamber. This leaves behind a porous network of cellulose, essentially the skeleton of the wood.

The innovation comes in what happens next: instead of filling those pores with synthetic materials, Baruah and undergraduate student Ridham Raval impregnate them with a mixture of egg whites and rice extract, along with a small amount of curing agent to maintain transparency. The result is a flexible, durable material that allows light to pass through while maintaining wood’s natural structure.

Beyond creating an interesting material, the researchers explored practical applications. In one experiment, they modified a birdhouse with a transparent wood window and measured its insulating properties compared to glass. When placed under a heat lamp, the interior temperature remained 9 to 11 degrees Fahrenheit cooler with the transparent wood window – suggesting potential energy-efficiency benefits for building applications.

The team also developed an electrically conductive version by incorporating silver nanowires into the wood, opening possibilities for wearable sensors or solar cell coatings. While the silver component isn’t biodegradable, Baruah hopes to experiment with alternatives like graphene to maintain the material’s eco-friendly credentials.

Though still in early development – the transparency could be improved, for instance – the approach demonstrates that innovative materials don’t necessarily require expensive or environmentally harmful components.

“I want to send a message to my undergraduate students that you can do interesting research without spending thousands of dollars,” said Baruah, emphasizing the accessibility of the approach.

As concerns about plastic pollution continue to mount, developments like this transparent wood could offer alternatives for everything from electronics to building materials – potentially transforming how we think about the materials in our daily lives while drawing wisdom from centuries-old building techniques that have withstood the test of time.