Since it was initially presented in 2016, transparent wood has actually been established by scientists at KTH Royal Institute of Technology as an ingenious structural product for developing construction. It lets natural light through and can even keep thermal energy.
The essential to making wood into a transparent composite product is to remove out its lignin, the significant light-absorbing element in wood. But the empty pores left by the lack of lignin require to be filled with something that brings back the wood’s strength and enables light to penetrate.
In earlier variations of the composite, scientists at KTH’s Wallenberg Wood Science Centre utilized fossil-based polymers. Now, the scientists have actually effectively checked an environmentally friendly option: limonene acrylate, a monomer made from limonene. They reported their lead to Advanced Science.
“The new limonene acrylate it is made from renewable citrus, such as peel waste that can be recycled from the orange juice industry,” states lead author, PhD trainee Céline Montanari.
An extract from orange juice production is utilized to produce the polymer that brings back delignified wood’s strength and enables light to go through.
The brand-new composite deals optical transmittance of 90 percent at 1.2 mm density and extremely low haze of 30 percent, the scientists report. Unlike other transparent wood composites established throughout the previous 5 years, the product established at KTH is planned for structural usage. It reveals durable mechanical efficiency: with a strength of 174 MPa (25.2 ksi) and flexibility of 17 GPa (or about 2.5 Mpsi).
Yet all along, sustainability has actually been a concern for the research study group, states Professor Lars Berglund, the head of the KTH’s Department of Fibre and Polymer Technology.
“Replacing the fossil-based polymers has been one of the challenges we have had in making sustainable transparent wood,” Berglund states.
Environmental factors to consider and so-called green chemistry penetrate the whole work, he states. The product is made without any solvents, and all chemicals are stemmed from bio-based basic materials.
The brand-new advances might make it possible for a yet undiscovered series of applications, such as in wood nanotechnology, Berglund states. Possibilities consist of wise windows, wood for heat-storage, wood that has integrated lighting function – even a wood laser.
“We have looked at where the light goes, and what happens when it hits the cellulose,” Berglund states. “Some of the light goes straight through the wood, and makes the material transparent. Some of the light is refracted and scattered at different angles and gives pleasant effects in lighting applications.”
The group is likewise dealing with Sergei Popov’s photonics group at KTH to check out the nanotechnology possibilities even further.
Reference: “High Performance, Fully Bio‐Based, and Optically Transparent Wood Biocomposites” by Céline Montanari, Yu Ogawa, Peter Olsén and Lars A. Berglund, 2 May 2021, Advanced Science.
Funding: Knut and Alice Wallenberg Foundation