CAS-MNP: Degradation of Plastics in the Environment: Decoupling the Roles of Polymer Type, Material Attributes, and Chemical Additives

With support from the Environmental Chemical Sciences (ECS) Program of the Division of Chemistry, Weile Yan and Margaret SobkowiczKline from the University of Massachusetts Lowell will investigate the environmental degradation behavior of plastics. In particular, the causal links between polymer properties, additive formulations, and their degradation will be investigated. This project will apply interdisciplinary approaches to study the transformation of plastic pollutants in the environment. The project aims to enable assessment of the long-term fate of the existing plastic pollutants, and also to inform future plastics design and processing strategies to minimize environmental accumulation. The PIs will engage a diverse student body at the institution through dedicated scholar and training programs and integrated lab and field learning experiences. The project will also lead to a community service project to increase public awareness of the local and regional sources of plastic pollutants in the Merrimack River watershed and the adjoining coastal environment. Existing studies on microplastics have revealed the importance of plastics fragmentation in the natural environment. However, the effects of the properties of different plastic materials and their processing history, including the presence of common additives such as antioxidants and UV stabilizers, on plastic degradation and fragmentation are largely unexplored. Plastic materials with well-controlled characteristics and additive formulations will be prepared in order to carry out systematic investigations to study the effects of polymer type, particle size and shape, and additive chemistry on plastic weathering and fragmentation. Characterizations of laboratory and field-collected samples to identify changes in polymer and surface chemistry, mechanical strength, and additive loss, in conjunction with quantitative analysis of fragmentation potential, are expected to generate new mechanistic insight into the formation of micro- and nano-plastics (MNPs) in the environment. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.