A team of scientists at the University of North Carolina at Chapel Hill has developed a groundbreaking chemical recycling method that could offer a cleaner, more sustainable solution to the growing global problem of tire waste.
Each year, more than 274 million tires are discarded in the United States, with millions ending up in landfills. The study, recently published in the journal "Nature," outlines a novel method of breaking down used rubber and transforming it into useful industrial materials—specifically, precursors for epoxy resins used in products like adhesives, wind turbines and automotive parts.
“There’s a substantial amount of rubber accumulating in landfills,” said Dr. Aleksandr Zhukhovitskiy, lead author of the study and an assistant professor of chemistry at UNC-Chapel Hill. “These tires provide an environment for microorganisms to grow and potentially release toxic materials, and over time, they can generate microplastics and other pollutants we don’t yet fully understand.”
Zhukhovitskiy’s lab has been focused on what he calls “editing the skeletons” of plastic materials—changing the structure of polymers to make them easier to break down or reuse. In the case of tire rubber, the researchers used a gentle chemical process to insert nitrogen atoms into the material, creating a pathway for it to break apart into smaller, soluble pieces.
“Rubber is made of carbon atoms tightly linked together, which makes it really tough to deconstruct,” he said. “But if you change its chemical composition, you can open the door to breaking it down—and then build something entirely new from the pieces.”
Unlike traditional recycling methods—such as shredding tires into small particles or using high-heat pyrolysis—this chemical process operates at low temperatures and uses mild, environmentally friendly solvents. Zhukhovitskiy says that makes it a cleaner, less energy-intensive alternative.
“You’re not burning the material, so you avoid releasing pollutants like carbon dioxide and sulfur oxides, which can contribute to acid rain,” he said.
The end result is a liquid solution that contains amine-functionalized polymers, which can then be used to create epoxy resins with performance properties similar to those made from bisphenol A, a compound under scrutiny for its environmental and health risks.
“I was honestly shocked at how well it worked,” Zhukhovitskiy said. “Often in science, your ideas don’t go as planned. But this one just clicked.”
While the innovation offers promising environmental benefits, it’s still in the early stages. Zhukhovitskiy said scaling the process to industrial levels will require further research, collaboration with engineers, and substantial funding.
“To go from a discovery in a university lab to something that can be adopted at scale is a long road,” he said. “But it’s a road worth taking if it helps improve environmental and human health.”
The research team is now seeking grants to support larger-scale experiments and explore additional applications of the technique, including recycling other hard-to-break-down polymers.
“This kind of work starts in academic labs, but it’s where a lot of real-world innovation begins,” Zhukhovitskiy said. “If we support the next generation of scientists, they’ll be the ones creating cleaner technologies and shaping a more sustainable future.”