Erosion as a possible mechanism for the decrease of size of plastic pieces floating in oceans. (February 2018)

• Record Type: Journal Article
• Authors: Resmeriță, Ana-Maria; Coroaba, Adina; Darie, Raluca; Doroftei, Florica; Spiridon, Iuliana; Simionescu, Bogdan C.; Navard, Patrick
• Is Part Of: Marine pollution bulletin. Volume 127(2018)
• Page Start: 387
• Page End: 395
• Publication Date: 2018-02
• Subjects: Polypropylene -- Degradation -- Erosion -- Water -- Ocean; Marine pollution -- Periodicals; Marine Biology -- Periodicals; Water Pollution -- Periodicals; Mer -- Pollution -- Périodiques; Publications périodiques; Pollution des mers; Lutte antipollution; Electronic journals; 363.7394
• DOI: 10.1016/j.marpolbul.2017.12.025
• Languages: English
• ISSNs: 0025-326X

Abstract

Abstract: A sea water wave tank fitted in an artificial UV light weathering chamber was built to study the behaviour of polypropylene (PP) injected pieces in close ocean-like conditions. In air, the same pieces sees a degradation in the bulk with a decrease of mechanical properties, a little change of crystal properties and nearly no change of surface chemistry. Weathering in the sea water wave tank shows only a surface changes, with no effect on crystals or mechanical properties with loss of small pieces of matter in the sub-micron range and a change of surface chemistry. This suggests an erosion dispersion mechanism. Such mechanism could explain why no particle smaller than about one millimeter is found when collecting plastic debris at sea: there are much smaller, eroded from plastic surfaces by a mechano-chemical process similar to the erosion mechanism found in the dispersion of agglomerate under flow. Highlights: Polypropylene was weathered in ocean-like conditions with a UV sea water wave tank. Only surface changes are observed, contrary to weathering in air. Dispersion occurred by erosion, by a continuous detachment of sub-micron parts.