College of Engineering hosts Plastic Characterization Workshop

Event showcased core research facilities, advanced techniques

KINGSTON – July 18, 2022 — The College of Engineering hosted a workshop recently for researchers and industry leaders that showcased the advanced capabilities of its core research facilities that can be used for plastic characterization.

Irene Andreu, an adjunct professor of chemical engineering and the director of Operations for the Rhode Island Consortium for Nanoscience and Nanotechnology, organized the event. 

“The key thing about this workshop was that it [focused] on the type of material — so when I say polymers and plastics, I’m saying that very deliberately because if you’re a company that makes plastics, or if you’re doing pharmaceutical research, you refer to them as polymers,” she said. 

“The public associates plastics now as a bad thing because of micro plastics, so if you’re doing research on micro plastics, you talk to them about plastics,” she said, “but the thing is that the characterization techniques are the same for microplastics and manufactured polymers. So what I [wanted] to do with this workshop is bring people together that are looking at the exact same material, but from two different points of view.”

Andreu invited experts from Shimadzu Scientific Instruments (the manufacturer of most of the equipment in the core facilities), the American branch of the Japanese Shimadzu Corporation, to the event to speak about how others in the field are using these instruments. 

The presenters from Shimadzu and their topics were: Alan Owens, the use of gas chromatography-mass spectrometry for microplastic research; Gilbert Vial, the use of Fourier-transform infrared spectroscopy microscopy for plastic identification; Evan Moreira, the mechanical testing of composite materials; Meagan Moore, the use of liquid chromatography-mass spectrometry for polymer additives in the food industry; and Laura Mohanty, the thermal analysis of polymers. 

“We have a great relationship with the people at Shimadzu, so I’m very glad they came in-person,” Andreu said. It was the first time she had met many of them in-person, and it was the first time they had been able to see the facilities in-person as well.

“They were happy that the instruments have found a nice new home,” she said, “and they seem to be happy with the way that the facilities are managed and how the instruments are maintained.”

One of Andreu’s goals is to provide access to the facilities for students, researchers, a variety of industries, other academic institutions and government agencies to work on important issues like plastic and other types of pollution; pharmaceutical development, food testing, forensic toxicology, live cell imaging, fracture and stress analysis, among many others.

In addition to the team from Shimadzu, there were three presenters from URI: Vinka Oyanedel-Craver, a professor and associate dean of research for the Department of Civil and Environmental engineering, who gave the opening remarks; Tania Silva de Oliveria, a Ph.D. candidate in chemical engineering who does research in nanotechnology and colloidal science, who discussed atomic force microscopy to test the interaction of microplastics with bacteria; and Ph.D. candidate Sarah Davis.

Davis, who began her Ph.D. studies in biological and environmental sciences on the ecology and ecosystem sciences track last fall, explained how her team uses Raman spectroscopy for its research on environmental microplastics. 

“The focus of my research is investigating the presence, movement and impacts of microplastics in Rhode Island’s waterways, primarily in Narragansett Bay,” she said. “[We look at] pollutant transport in the bay, so waters like rivers and watershed areas surrounding the bay, and isolated freshwater areas as well. So just kind of getting a baseline understanding of what’s in the water, and on top of that, doing work to understand how it’s impacting the organisms.”

To get the samples that they use in the Raman microscope, Davis and her team take a 330-micron net which is about a third of a millimeter – or about a third of the size of the tip of a sharpened pencil – into the Bay and scrape the surface of the water. They then take the particles and put them under a high-resolution microscope to get a better view of what they look like, and then take a hot needle and poke them to see if they melt. If they do, then the sample is likely plastic, as opposed to other human-made products like spun cotton, or natural particles like rocks. 

After looking at the samples, the team takes a random sample of 20% of them to the Raman microscope. The researchers put the sample under the microscope and they can view it on a computer screen. Once it’s focused, the machine shines a laser on the object and produces a spectrum readout. Based on that readout, they’re able to identify the specific plastic in the sample.

In total, 55 people attended the event, including four from outside of the University, Andreu said. 

One attendee, Ire Asojo, is a rising sophomore in the Brown University/Rhode Island School of Design dual degree program. Asojo, who is studying the effect of input materials (different clays and burnout ratio) on ceramic water filters’ performance (strength and bacteria filtration), was interested in the event because she wanted to learn more about scientist’s work concerning microplastics.

“What interested me was knowing more about microplastics and the different ways of working

with and testing them.” she said. “I feel like I learned a lot. It’s very helpful to see what other people are working on, the different ways to analyze microplastics, and what applications these analyses have depending on what field you’re in.”

“It was really cool,” Davis said, “it was neat to hear the different applications for the types of machines that are in the core facilities.”

Davis also was glad for the opportunity to see how these machines can be applied to other fields, such as polymer manufacturing, and how that could be applied to her field. 

“It’s neat to hear what has already been done with those machines and how we might be able to sneak in our environmental stuff as well, in particular there’s the LC-MS (liquid chromatography-mass spectrometry), and we heard how they were testing for additives in wines and beers and different alcohols,” she said. “My mind was just asking ‘can we put some seawater in this? Can we do that with sea water samples?’”

“During the breaks people were chatting with each other and discussing their projects with researchers that they would not have met otherwise,” Andreu said, “I’m hoping that we get some new collaborations happening because of this.”

“People told me that they liked to see all of these techniques in context, and they got some ideas on doing things or using instruments that they hadn’t thought could be used for their research,” she said. “I think based on the feedback, we’ll try to host something like this again.”

The facilities are open to researchers and the general public both within and outside of the University, Andreu said, and she shared that she’d love to speak with people who are interested in learning more about them.

“If anybody ever wants to come and see the lab, whether it’s in the context of plastics or something else, or if people are just curious about the core facilities, they can contact me or come to the College of Engineering,” she said, “I’d be happy to show anybody around and talk about microscopes.”

Andreu can be reached via email at iandreu@uri.edu or by phone at 401-874-6885.

Mary Lind, a graduate student who works in URI’s Department of Marketing and Communications, wrote this release.