By Cecilia Smith, Administrative Assistant, ACS Green Chemistry Institute
How can polymer additives help create stronger and more sustainable recycled plastics? At Columbia University, Assistant Professor Neil Dolinski explores this possibility through his group’s research on dynamic polymers, or polymers composed of bonds that reversibly make and break. As additives in recycled plastic, these dynamic polymers can enhance the mechanical properties of recycled materials. Supported by a 2023 Early Career Postdoctoral-Faculty Bridge Grant, Dolinski’s research advances circularity and touches on key U.N. Sustainable Development Goals.
The plastics crisis is one of the most pressing challenges facing humans and the environment, yet a number of obstacles hinder progress towards circularity and plastic pollution mitigation. When it comes to the end-of-life fate of plastics, the gap between global plastics production and recycling or valorization is quite staggering: in recent years, only about 9% of global plastic waste is recycled annually.
One of the reasons plastics recycling remains elusive is the poor mechanical performance of polymers after the melting and extrusion steps that occur during the recycling process. Neil Dolinski, Assistant Professor at Columbia University, aims to address this challenge through his research group’s work. Dolinski received a 2023 Early Career Postdoctoral-Faculty Bridge Grant, which allowed him to establish his research group in the Chemical Engineering department at Columbia and helped launch his work on polymer research.
Dolinski’s group focuses on developing dynamic polymers (polymers composed of bonds that reversibly make and break) that can act as additives to improve various aspects of polymer recyclability. The additives Dolinski’s group is developing are derived from biomass and industrial waste products, making them both renewable and more sustainable than many common polymer additives, which tend to be non-biobased. Dolinski’s group will explore the ability of these dynamic additives to improve the mechanical properties of recycled polymers. By aiding in plastic reclamation, the work touches on several U.N. SDGs, including industry, innovation, and infrastructure; responsible consumption and production; life below water; and life on land.
Since starting his position at Columbia University in January 2024, Dolinski has seen promising results in this work. His preliminary findings indicate that his group’s dynamic additives have been shown to “heal” polymer chain scission and improve the mechanical properties of recycled high-density polyethylene (HDPE) including modulus, yield stress, and ultimate strain, relative to virgin HDPE. His group also aims to use their dynamic additives to make immiscible blends of plastics compatible, such as low-density polyethylene and polystyrene.
Dolinski’s sustainability grant also provided resources for including green chemistry in his teaching. While Dolinski’s department at Columbia offers a new undergraduate course in Green Chemical Engineering, Dolinski has built on this small foundation by introducing a chemical engineering course targeted towards advanced undergraduate and materials-leaning graduate students, titled “Polymer Chemistry for Sustainable Solutions.” Additionally, Dolinski has recently begun teaching a senior Chemical Engineering and Applied Chemistry Lab course, which he aims to rework to include more of an emphasis on green chemistry and green engineering.
“For the next 2-3 years, I will be overhauling and replacing experiments with more modern examples that touch on sustainability,” says Dolinski. “Currently, I am rewriting experimental handbooks to incorporate the Principles of Green Chemistry as motivators for the modules – particularly enzyme kinetics (catalysis) and solar energy (use of renewable feedstocks) experiments.”
As both an educator and researcher, Dolinski has gained significant momentum in a crucial field of sustainable chemistry. “The ECP Bridge grant has been instrumental in accelerating my independent career in this exciting and important area of research,” says Dolinski.