UT’s Polymer Scientists are on the Forefront of Plastic Waste Reform
UT’s Polymer Scientists are on the Forefront of Plastic Waste Reform
By Abby Ann Ramsey Peters (’24)
Plastics have been around since the late 19th century, but they didn’t become ubiquitous for most Americans until the 1950s. Today, we buy food stored in plastic tubs, sip iced coffee from plastic straws punched through plastic cups, and microwave our leftover food in plastic containers.
These everyday actions form something called microplastics, which are smaller than a single human hair, and nanoplastics, which are much smaller than that. It’s something Paul and Wilma Ziegler Professor of Chemistry Mark Dadmun, who specializes in polymer science, knows all too well.
“Washing your clothes, driving your car tires down the road—these everyday actions that create a lot of friction create microplastics and nanoplastics,” says Dadmun, who also serves as associate dean for research and creative activity in the College of Arts and Sciences at the University of Tennessee, Knoxville. “We have been creating microplastics for a long time, and they’re everywhere. That makes studying them very difficult.”
While health and environmental experts look at where plastic trash ends up and how it impacts our bodies, there’s little discussion around how the microplastics and nanoplastics themselves are formed on a molecular level. That’s where polymer science comes in.
Mark Dadmun, Paul and Wilma Ziegler Professor of Chemistry and Associate Dean for Research and Creative Activity in the College of Arts and Sciences.
If nanoplastics aren’t properly expelled from the human body, how are those fragments of plastics structured, and are there different ways to construct them? If they’re lingering in the environment, what could polymer science reveal about recycling methods and the types of plastics we use every day to minimize that? To answer those questions, it’s important to understand how the nanoplastics and microplastics are formed.
Dadmun, along with students like Shelby Watson-Sanders (’25), is researching nanoplastics to determine how they form.
“We’re trying to answer the fundamental problems, and the research being done now may not seem like it’s going to turn around and solve problems tomorrow, but it informs the decisions that will need to be made years from now,” Dadmun says.
The research group recently published papers in both ChemSusChem and Nature Communications detailing their efforts in polymer chemistry to determine how nanoplastics form.
The research essentially tracks how test plastics break down and examines what crystalline structures—also known as nanoplastics—are left behind. The researchers also use X-ray scattering to characterize plastic samples. The X-rays interact with the samples to reveal a distinct structure that can clue them in on what kind of plastic (a Coke bottle versus a pill bottle versus a grocery bag) it came from.
“We need to start worrying about and studying nanoplastics, and I think our studies may serve as a starting point for that because it starts that conversation,” says Dadmun.
Because of the Paul and Wilma Ziegler Professorship, we have the opportunity to go and try things that we may not be able to try otherwise. Having that flexibility to take chances is where some of the most important progress in research happens.”
Mark Dadmun, Paul and Wilma Ziegler Professor of Chemistry
The Dadmun group uses X-ray scattering to characterize plastic samples.
The team’s research has not been linear—it’s been a winding road of discoveries that open up more possibilities.
Watson-Sanders, who has a PhD in chemistry and was a postdoctoral researcher for the past year, was funded to research recycling Coke bottles. She completed and published that research but also played a role in four other published papers along the way, contributing to a growing bank of knowledge in the polymer science community.
“All the other papers in between were random shoot-offs, where we were thinking, ‘Oh, what about this?’” Watson-Sanders says.
To take the time and resources to get creative in the lab is a rare privilege that has led to change-making discoveries. Dadmun’s endowed professorship gives him the flexibility to let his research team dip their toes into uncharted waters.
“Because of the Paul and Wilma Ziegler Professorship, we have the opportunity to go and try things that we may not be able to try otherwise,” says Dadmun. “Having that flexibility to take chances is where some of the most important progress in research happens.”
“I think it’s important for the entire population to realize how things that we’re currently using might affect us later on. Understanding plastics also helps us understand what’s going on in places like the Tennessee River, where fish are subject to eating these plastics.”
Shelby Watson-Sanders (’25)
A paper published by the team at the end of May in Green Chemistry explores a strategy of upcycling polyethylene terephthalate (PET) bottles, born from experimentation in the lab.
“That was an idea I had randomly in lab, and Dr. Dadmun said, ‘Sure, go ahead and do it,’” Watson-Sanders says. “And now we have a patent submitted on it, and it’s some of my favorite work I’ve done, because I had the idea, and he was able to give me the green light to try it out.”
The results of Dadmun’s and his group’s research could have sweeping impacts on questions that researchers in health, environmental studies, and other fields are trying to answer—but the implications spread past the world of academia.
For people across Tennessee, understanding the effect of certain kinds of plastics arms them with the tools they need to inform their decisions.
“I think it’s important for the entire population to realize how things that we’re currently using might affect us later on,” Watson-Sanders says. “Understanding plastics also helps us understand what’s going on in places like the Tennessee River, where fish are subject to eating these plastics.”
The work necessary to equip people with that information doesn’t happen in a vacuum. That’s why attending conferences and forming relationships with other researchers is so important to the pivotal research being done by polymer scientists like Dadmun.
“The Paul and Wilma Ziegler Professorship provides me with a cushion, allowing me to go to conferences,” says Dadmun. “Having those opportunities gives me a chance to broaden my network and see what other research is happening.”
UT is at the forefront of the conversations surrounding micro- and nanoplastics. And Dadmun’s team is just getting started.
“Our research in nanoplastics and microplastics is really just getting off the ground,” says Dadmun. “There’s a lot of things we could be doing, or places we could go with it, but also possibilities I don’t even see yet, which makes this work incredibly exciting.”
