Novel Method Transforms Discarded Plastics into High-Value Polymers

Chemists from Oak Ridge National Laboratory have developed a novel technique to transform waste plastics into higher-value polymers, boosting sustainability.

• Upcycling reworks polymeric building blocks to yield improved plastics from waste
• Ring-opening and cross metathesis were used to customise new polymer structures
• Scientists aim for broader applications, including thermosets and environmentally friendly solvents

In a notable step towards more sustainable management of plastic waste, chemists at the Department of Energy’s Oak Ridge National Laboratory (ORNL) have announced an upcycling approach that may help rescue massive quantities of plastics from landfills. With an estimated 450 million tonnes of plastic discarded globally every year, and only 9% currently recycled, the technique is attracting the attention of researchers seeking more efficient and eco-friendly materials.

Precise Molecular Editing

At the heart of this development is a molecular editing process inspired by major chemical breakthroughs, including the metathesis reaction honoured with the 2005 Nobel Prize in Chemistry. By enabling the breaking and reforming of double bonds between carbon atoms, metathesis allows polymer subunits to exchange places, creating polymers with altered properties. ORNL’s Jeffrey Foster, who led the study published in the Journal of the American Chemical Society, explained the potential: “This is CRISPR for editing polymers,” he said. “However, instead of editing strands of genes, we are editing polymer chains. This isn’t the typical plastic recycling ‘melt and hope for the best’ scenario.”

Using ring-opening metathesis polymerisation and cross metathesis, the ORNL team rearranged the polymeric building blocks of discarded plastics such as polybutadiene (found in rubber tyres) and acrylonitrile butadiene styrene (used in plastic toys, keyboards, and more). Foster highlighted the significance of this approach for neglected waste streams: “This is a waste stream that’s really not recycled at all,” he noted. “We’re addressing a significant component of the waste stream with this technology. That’d make a pretty big impact just from conservation of mass and energy from materials that are now going into landfills.”

Industrial Potential and Next Steps

By dissolving synthetic or commercial polymers in dichloromethane at a modest temperature of 40°C for under two hours, the researchers introduced a ruthenium catalyst widely used in industrial settings. This catalyst facilitated the insertion of new functional units into the polymer chain, preserving nearly all the original mass. Foster emphasised the efficiency of this method: “The new process has high atom economy. That means that we can pretty much recover all the material that we put in.”

Because this method sidesteps traditional melting processes that degrade plastic quality, the resulting polymers retain their desirable properties or can even exhibit improved characteristics. Importantly for industrial-scale use, the approach can be adjusted to produce softer, more elastic materials, or robust thermosets like epoxy resins that cannot be reshaped once cured. While challenges remain—such as optimising solvents and managing plastic pre-processing—the team foresees adapting their approach to other polymer backbones, supporting a vision of a circular economy in which waste materials gain renewed value.

Researchers in the UK and worldwide may find immediate relevance in adopting these advanced polymer editing techniques for diverse applications. From developing next-generation medical devices to creating more sustainable packaging, ORNL’s upcycling strategy could lower reliance on virgin plastics. As efforts intensify to reduce global plastic pollution, this method offers a practical route to align environmental and economic interests in the pursuit of sustainable innovation.

As the ORNL team continues refining its technique, industry partners may see opportunities to integrate upcycling into existing manufacturing pipelines. By limiting energy-intensive steps typically associated with plastic reconstitution, this technology could pave the way for cost-effective production of novel polymer materials with improved mechanical and thermal properties. Future work will look at additional polymer classes, bridging the gap between fundamental science and commercial deployment.