A new adhesive dissolves in alkaline solutions, making plastic recycling cleaner and more effective. This could greatly reduce waste and improve material reuse.
A recent study highlights a new adhesive that can be cleanly removed from plastic bottles and packaging before disposal, potentially improving the quality of recycled plastic.
Conventional adhesives used for attaching labels often leave behind residues that hinder the recycling and reuse of plastic.
Researchers from the University of Reading’s Department of Chemistry have developed a polymer adhesive that dissolves when exposed to basic or alkaline solutions. This allows labels to remain securely attached during use but enables easy removal during the recycling process, reducing contamination and enhancing recyclability.
Matthew Hyder, lead author of the research, said: “Existing commercial adhesives can prove extremely difficult to remove from plastic surfaces because of their chemical composition. Our new polymer adhesive has been designed so that it can be removed from a plastic surface when exposed to basic or alkaline solutions. By making labels that can be removed completely, we are helping improve the quality of recycled plastic and its usefulness in its next life.”
Multiple Uses
Published last month in the journal Macromolecules, the study describes how researchers designed and generated a polyurethane that incorporated sulfonyl ethyl urethane units, which act as a chemical switch when exposed to certain substances. In tests, treating the polymer adhesive with basic or alkaline solutions triggered this switch, making it lose up to 65% of its sticking power on a range of surfaces.
During everyday use, these adhesives have the potential to work just as well as current commercial alternatives. When tested, they proved strong enough at different temperatures on both glass and aluminum surfaces, making them suitable for everything from food containers to shipping packages to electronic appliances.
This development, sponsored by Domino Printing Sciences PLC in conjunction with the University of Reading, could transform how waste is handled across many industries. By making it easier to separate different materials during recycling, the quality of recycled materials could significantly improve, reducing the amount of waste that ends up in landfills.
Reference: “Thermally and Base-Triggered “Debond-on-Demand” Chain-Extended Polyurethane Adhesives” by Matthew J. Hyder, Jessica Godleman, Ann M. Chippindale, James E. Hallett, Thomas Zinn, Josephine L. Harries and Wayne Hayes, 2 January 2025, Macromolecules.
DOI: 10.1021/acs.macromol.4c02775
Never miss a breakthrough: Join the SciTechDaily newsletter.
Follow us on Google and Google News.
3 Comments
This is tremendous! When I was 6 years old my job was to remove labels from bottles at my father’s independent pharmacy. I spent hours peeling soaking and scraping. Even today as an adult when attempting to recycle a bottle it often isn’t easy. Keep changing the world!
Keep on experiment and Devolp Verious way rejected pet Bottles .this pet Metrial is unbreakable .also EAVER Lasting .
A light print is far more recycle friendly