CBE Colloquia - Understanding Polymer Degradation: Structural Pathways to Microplastics and Biodegradations

Polymers have profoundly impacted modern society through applications in food preservation, lightweight transportation, electronics, and advanced medical technologies such as extracorporeal membrane oxygenation (ECMO). At the same time, increasing environmental concerns—particularly related to microplastics (MPs)—have intensified research interest. A fundamental understanding of MP formation, physicochemical properties, and environmental behavior is essential, yet remains incomplete.
Polymer degradation involves the loss of mechanical integrity, color changes, and morphological alterations under environmental stressors including heat, light, chemicals, microorganisms, and mechanical forces. Degradation proceeds through multiple pathways. Physical degradation occurs via fragmentation driven by mechanical or electrical stimuli, while chemical degradation is initiated by abiotic reactions that modify molecular structures, reduce molecular weight, and introduce new functional groups, often leading to MP formation.
Biodegradation represents a desirable end-of-life pathway, occurring through enzymatic processes following biofilm adhesion. However, balancing long-term performance stability during use with efficient degradation after disposal remains a major challenge.