Seminar

Understanding degradation behaviours of plastic polymers in common disposal environments is crucial to evaluate their polluting effects. This project includes in situ experiments to assess the 40-day degradability of conventional plastics in marine environments, and the six-month degradability of bioplastics in open-air and marine environments. This study reveals the early degradation signs of conventional plastics in marine environments, and their engagement in synergistic oxidative processes and oxidation product removal processes. Polymers with styrene groups or heteroatoms showed larger susceptibilities to oxidative processes, whereas pure polyolefins and expanded polystyrenes demonstrated higher fragmentation risks. Despite the objective of serving as a sustainable alternative to conventional plastics, bioplastics in this study demonstrated suboptimal degradability in natural environments. This study also reveals the larger degradability of biodegradable plastics that are bio-based over the fossil-based ones. By outlining and comparing the degradability of different polymers, this project sheds light on the identification of polymers with higher degradability and lower fragmentation risks to limit plastic pollution.

Additional information: Miss Cheung Ka Hei, ccc62000@connect.hku.hk