Reversible glue developed by scientists to simplify packaging recycling
Key takeaways
- Newcastle University researchers have developed a reversible, water-based glue that bonds dissimilar materials.
- The solution enables easier reuse and recycling of packaging components such as labels and laminates.
- The glue uses clay-based “one-pot” formulations, offering a shelf life of at least one year.
Scientists from Newcastle University, UK, have developed a reversible glue that functions like conventional glue, but can be debonded on demand. The solution can be used for laminates and bottle labels, enabling easy separation for reuse or recycling.
The reversible glue is a water-based emulsion that enables bonding between dissimilar materials and can be separated on demand using acidic or alkaline water.
According to the study, published in Soft Matter, the new glue’s shelf life at room temperature is at least a year. It is said to work on a wider variety of surfaces compared to white-glues. The solution can be applied to PP and PE plastics.
Dr. Adriana Sierra-Romero, research associate at the School of Engineering and first author of the paper, says: “Reversible adhesives are starting to attract attention in the industry. They’re not yet mainstream, but we expect adoption to grow as companies look for more sustainable solutions.”
Low-cost scaling
The researchers incorporated clays into the glue formulations. Clays are commonly used as thickening agents to inhibit dripping, but can also enable debonding without the need for two separate formulations. This “one-pot” reversible glue aims to simplify recycling workflows.
Dr Adriana Sierra-Romero, professor Katarina Novakovic and professor Mark Geoghegan.Katarina Novakovic, professor of polymer engineering and co-investigator on the project, says: “It is more critical than ever to develop technologies that will enable net zero targets and our glue is doing exactly that.”
The glue is said to be developed from cheap materials, supporting scalability. Unlike many water-based adhesives, it does not experience bond failure in humid environments.
In the packaging industry, Fedrigoni recently unveiled its Wet-Glue Collection, highlighting wet glue application as an alternative for customers seeking to reduce their plastic use.
Last year, Henkel introduced Technomelt EM 335 RE, a hot melt adhesive designed to meet recycling requirements. The innovation aims to make PET bottle recycling compliant with PPWR.
