Textural, surface and chemical properties of polyvinyl chloride particles degraded in a simulated environment

• Published in: Marine pollution bulletin Vol. 133; no. C; pp. 392 - 401
• Main Authors: Tang, Chih-Cheng, Chen, Huey-Ing, Brimblecombe, Peter, Lee, Chon-Lin
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01-08-2018; Elsevier
• Subjects: Environmental degradation; Marine debris; Marine plastics; Surface morphology; Thermal degradation; Ultraviolet B (UVB) radiation degradation; Ultraviolet B (UVB) radiation degradation; Environmental degradation; Surface morphology; Marine debris; Marine plastics; Thermal degradation
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2018.05.062

Virgin polyvinyl chloride (PVC) particles were exposed to heat, ultraviolet B (UVB) and solar radiation either in artificial seawater or in air for different periods of time. The surface and chemical properties of fresh and degraded particle surfaces were determined via image analysis using scanning electron micrographs, a Brunauer-Emmett-Teller (BET) specific surface area analyzer and infrared spectroscopy. Thermal and UVB degradation resulted in unique PVC morphologies. In addition, the increased presences of functional groups were evident as dehydrochlorination and oxidation during the degradation process, which altered the chemical properties of PVC. In contrast, under solar exposure with or without seawater, unevenness to the surface was noted that seems to originate from degradation of the PVC surface; in addition, no new functional groups were found. This suggests that the chemical properties of PVC are stable over extended periods in the marine environment.
•PVC exposed to heat and UVB radiation presented altered morphologies and produced new functional groups on the surface.•The chemical properties of eroded PVC underwent a dehydrochlorination and oxidation process during the aging process.•Seawater slows down UVB degradation and inhibits formation of ester carbonyl functional groups.•The chemical properties of PVC debris appear durable over extended periods in the tropical marine environment.•Textural analysis of SEM images represents an independent set of additional parameters.