Study on the photoaging process and metal ion release of plastic films with two kinds of structures in marine environment: Aliphatic and aromatic polymers

Mar Pollut Bull. 2024 May 18:203:116474. doi: 10.1016/j.marpolbul.2024.116474. Online ahead of print.

Abstract

The prevalence of plastics in the oceans has significantly intensified microplastic pollution, contributing to broader marine secondary pollution issues. This paper examines how plastic structure affects the aging characteristics of plastics and the release of metal ions, to better understand this secondary source of marine pollution. This study simulate the photoaging of plastics in natural environments, focusing on aliphatic and aromatic polymers. The results showed that the photodegradation degree was higher for aliphatic than aromatic polymers. All polymers contained thirteen detectable metals, with their release increasing over time due to photoaging, The release dynamics of these metal ions correlated more strongly with the level of polymer degradation rather than with the polymer structure itself, adhering to a second-order kinetic model driven by surface and intraparticle diffusion processes. The results will help control and treat marine plastic pollution.

Keywords: Marine; Mechanism; Metal additives; Plastic; Release characteristics; UV irradiation.