As interest grows in using wood in high-performance buildings, researchers continue to push the boundaries of what is possible with wood assemblies. Researchers at KTH Royal Institute of Technology in Stockholm, Sweden, have developed wood that is transparent, insulates better than glass, and can store and release heat, according to the American Chemical Society.
The process for making wood transparent was developed first by the research team. Three years ago they discovered that by removing removing lignin from the cell walls in balsa wood and adding acrylic, it was possible to create a wood product that is translucent, yet hazy. It also is able to bear heavy loads.
By encapsulating a polymer called polyethylene glycol (PEG) into the wood, researchers have now been able to add thermal storage capacity to the clear wood. PEG absorbs heat and melts, and then releases the heat as it resolidifies. Researchers envision the material could be used at the building’s envelope to prevent heat penetration during the day, and release heat into the interior at night. This reduced demand on the HVAC system, plus the daylighting benefit provided by the translucency of the material could help reduce energy demand.
With further development, researchers say the material could be fully biodegradable, if the acrylic is replaced by a bio-based polymer. Researchers expect transparent wood to be available for use in building interiors within five years.
The research was presented at the American Chemical Society Spring 2019 National Meeting & Exposition.
Naomi Millán is senior editor of Building Operating Management.
