The Recycle Pillar
The Trienens Institute Recycle pillar aims to help solve the plastics pollution crisis and create a viable circular economic model at scale.
Decarbonization research and innovation are central to the work of the Paula M. Trienens Institute for Sustainability and Energy. Together, the Trienens Institute Pillars of Decarbonization are building a suite of complementary solutions for a vibrant, sustainable future. Northwestern researchers, who are global leaders in their fields, are guiding diverse teams of experts to progress in this urgent mission.
What is plastic recycling important?
Demand is skyrocketing for all forms of plastic, from a candy box to the tires on a car. In one year, 100 pounds of plastic are produced per person on the planet. That’s 800 billion pounds total. Yet less than 10% of plastic waste is recycled.
In addition, the vast majority of plastic items are currently derived from fossil fuels. To create new plastic, those fossil fuels go through energy-intensive processes to refine the chemicals that are transitioned into plastic. Those processes release carbon dioxide (CO2) into the atmosphere.
Across the board, energy is saved when plastic is recycled as compared to producing new plastic, while fewer items wind up in landfills and circulate through the environment as microplastics.
Why is it challenging to recycle plastic?
All plastic is not equal. There are two main classes, thermoplastic and thermosets, which are then further categorized based on their chemical composition. They cannot be mixed when recycled, unlike materials such as glass or aluminum.
Thermoplastics can be melted and remolded into new products. However, there are limits to how many times they can be recycled because this process also slowly breaks down the polymer chains.
Thermosets have a network structure that cannot melt that was designed to endure indefinitely.
How can plastic be produced more sustainably?
As part of the Paula M. Trienens Institute Recycle pillar, Northwestern is leading the creation of advanced polymers and processing methods for materials that will help solve the plastics pollution crisis and create a viable circular economic model at scale. The pillar is one of Trienens' Six Pillars of Decarbonization aimed at leading interdisciplinary research in decarbonization.
An emerging area of research involves using carbon dioxide as a feedstock for new forms of plastic.
The Northwestern Solution
Research into upcycling some of the most common types of thermoplastics to extend their life, has been developing. In addition, Northwestern researchers and their partner organizations are developing a circular economy for a large subset of thermosets called polyurethanes. Recent advancements have included the development of methods to recycle polyurethane, followed by the discovery of a process to recycle polyurethane foam directly back into polyurethane foam for new uses.
Current Projects
LEARN MOREThe Experts
John Torkelson, Capture Pillar Co-Chair
John Torkelson
Walter P. Murphy Professor of Chemical and Biological Engineering and Materials Science and Engineering
John Torkelson earned his B.S. degree in Chemical Engineering from the University of Wisconsin, where he conducted research under Prof. James Koutsky and Prof. R. Byron (Bob) Bird. As an undergraduate and before pursuing his graduate studies, Torkelson completed internships at the Institute of Paper Chemistry in Appleton, Wisconsin, N.V. Philips Gloeilampenfabrieken in Eindhoven, the Netherlands, and the ARCO Research Laboratories in Plano, Texas. He obtained his Ph.D. in Chemical Engineering at the University of Minnesota under Prof. Matthew Tirrell. Upon completing his Ph.D., Torkelson embarked on his independent academic career at Northwestern University in 1983 as an Assistant Professor in the Department of Chemical Engineering and the Department of Materials Science and Engineering. He was promoted to Associate Professor in 1988 and to Professor in 1992. In 2002, he was appointed the Walter P. Murphy Professor of Chemical and Biological Engineering and of Materials Science and Engineering. From 1997 to 2002, Torkelson served as Associate Dean for Graduate Studies and Research in Northwestern’s McCormick School of Engineering and Applied Science. From 2003 to 2006, he was Director of Northwestern’s Materials Research Center and the NSF-MRSEC. He has also chaired the Materials Engineering & Science Division of AIChE, the Division of Polymer Physics of the APS, and the Gordon Research Conference on Polymer Physics. Torkelson has broad research interests in polymer science and engineering, recently focusing on two areas related to advancing (1) the methods and applications of polymer sustainability, particularly in developing fully reprocessable network polymers through dynamic covalent cross-links and utilizing CO2 as a reactant in polymer synthesis, and (2) the understanding and applications of polymer nanoscience and nanotechnology. His interest in polymer sustainability is unusually long-standing; his first publication on polymer recycling appeared in 1999.
Torkelson has been recognized for his excellence in teaching and research. He has received the Tau Beta Pi Outstanding Teaching Award and the Northwestern Engineering Advisor of the Year Award and has been named Engineering Teacher of the Year at Northwestern twice. Additionally, he has received the NSF-Presidential Young Investigator Award, the Wiley Polymer Physics Prize, the Charles M. Stine Award from the Materials Engineering and Science Division of AIChE, and two Best Paper Awards from the Society of Plastics Engineers Annual Technical Meeting. In 2024, ScholarGPS rated Torkelson as the #1 Highly Cited Researcher in the topic area of Transition Temperature, #3 in the topic area of Glass Transition, and #95 in the topic area of Polymers.
William Dichtel, Recycle Pillar Co-Chair
William Dichtel
Robert L. Letsinger Professor of Chemistry
William Dichtel received a B.S. degree in Chemistry from MIT, where he performed research with Prof. Tim Swager. Dichtel obtained his Ph.D. degree from UC-Berkeley under Prof. Jean M. J. Fréchet. He was a joint postdoctoral researcher with Prof. Fraser Stoddart, UCLA, and Prof. James Heath, Caltech. He began his independent academic career at Cornell University in 2008 and was promoted to Associate Professor in 2014. In 2016, he took sabbatical at UC-Berkeley as a Visiting Miller Professor and then moved to Northwestern University as the Robert L. Letsinger Professor of Chemistry. The unifying theme of Dichtel’s research is the use of organic synthesis to control the structure and reactivity of molecules, materials, and interfaces across chemical environments. His research has expanded the study of polymerization processes into the second and third dimensions in an emerging class of polymers known as covalent organic frameworks (COFs).
Dichtel’s research has been recognized nationally and internationally. He received the NSF CAREER Award, Beckman Young Investigator Award, ACS Cope Scholar Award, National Fresenius Award, and the IUPAC/Polymer International Award. Dichtel was also the recipient of the prestigious MacArthur Fellowship, the Doolittle Award, the Baekeland Award, the FRED Cottrell Award and the 2020 Blavatnik Award.
Subeen Kim
Subeen Kim
Graduate Student, Dichtel Group
Recycle Pillar Representative,
Trienens Research Implementation Committee (TRIC)
subeenkim2026@u.northwestern.edu
Logan Fenimore
Logan Fenimore
Graduate Student, Torkelson Group
Recycle Pillar Representative,
Trienens Research Implementation Committee (TRIC)
loganfenimore2025@u.northwestern.edu
Charles Musgrave
Charles Musgrave
Kreamer CleanTech Innovation Fellow,
Paula M. Trienens Institute for Sustainability and Energy
Postdoctoral Scholar, Sargent Group
charles.musgrave@northwestern.edu
In the News
New foam-to-foam recycling process opens doors to a circular economy for key plastics
Researchers discover how to dismantle and rebuild a common form of polyurethane | FULL STORY >
Confronting our planet’s polymer problem
Northwestern researchers seek solutions to the plastics pollution dilemma with new ideas on polymer design and upcycling | FULL STORY >
Tire dumps and aging mattresses may soon be relics of the past
Researchers are using simple chemistry to bring new life to 'non-recyclable' materials | FULL STORY >
How can I support polymer recycling?
You can support cutting edge research in carbon capture through the Trienens Institute Capture Pillar in several ways. Become a scientific partner or make a gift in support of the Institute. For industry professionals and other leaders who wish to go deeper, consider corporate partnership opportunities. For broader impact, consider joining the Trienens Institute Executive Council.