A by-product of the pulp and paper industry has been turned into a safe and reusable hot-gun glue that could replace solvent-based adhesives that are toxic to humans and the environment. That is according to Ziwen Lv, a researcher from the Beijing Forestry University, who, with colleagues, has created glue from xylan, a component of plant cell walls.
“Xylan is the material that holds cellulose together, although it is not itself a ‘glue’ in the traditional sense,” according to Nick Aldred from the University of Essex, UK, who was not involved in the study. “This work aims to repurpose it as a glue.”
Lv’s team used sodium periodate and sodium borohydride to chemically modify the xylan, turning it into dialcohol xylan. They say the resulting glue, which is extruded from a hot gun, has a bonding strength of 30 megapascals, surpassing conventional adhesives, including epoxy resin.
The team focused on constructing plywood, using sheets of thin walnut timber held together by the xylan glue. In their research paper, the team says their three-ply product performed comparably with those made with phenol–formaldehyde resin adhesives and maintained its adhesion strength even after 10 reuse cycles. But the xylan plywood had a significant drawback. After soaking in water for one hour, the xylan glue dissolved, causing the sheets to separate.
Jonathan Wilker at Purdue University, Indiana, says sustainable replacements are needed for all of the petroleum-based adhesives currently in use. “[The] bonding performance [of the new glue] looked to be substantial, particularly with wood substrates,” Wilker says. “The life cycle assessment and water resistance results fell a bit short of incumbent glues now in use.”
“If it can be rolled out at scale in the plywood industry, it could be transformative,” Aldred says. “Plywood is one of the last remaining consumer products containing materials like phenol and formaldehyde, which were banned in products like cosmetics years ago.”
For more information: Lv, Z., Yan, X., Jia, S. et al. Bio-based hot-melt adhesive from xylan. Nat Sustain (2025). https://doi.org/10.1038/s41893-025-01579-9
