Sewage sludge induces changes in the surface chemistry and crystallinity of polylactic acid and polyethylene films

Research output: Contribution to journalArticlepeer-review

9 Scopus citations

Abstract

Plastic pollution is a major threat facing our environment. To understand the full effects, we must first characterize how plastics break down in environmental systems. Heretofore, there has been little work examining how exposure to sewage sludge facilitates the degradation of plastics, particularly of plastics that have been previously weathered. Herein, we characterize how the crystallinity, surface chemistry, and morphology of polylactic acid (PLA) and polyethylene (PE) films change due to sludge exposure. In this work, sludge-induced changes in carbonyl index were found to depend on the level of prior exposure to ultraviolet (UV) irradiation. The carbonyl indices of un-irradiated films increased while those of UV-aged films decreased after 35 days of sludge exposure. In addition, the carbon‑oxygen and hydroxyl bond indices of PE films increased with sludge exposure, suggesting the surface oxidation of PE. As for PLA, crystallinity was found to increase with sludge exposure, consistent with a chain scission mechanism. This work will help to predict the behavior of plastic films after transfer from wastewater to sewage sludge.

Original languageEnglish (US)
Article number164313
JournalScience of the Total Environment
Volume890
DOIs
StatePublished - Sep 10 2023

Bibliographical note

Funding Information:
This research was funded through the Environment and Natural Resources Trust Fund (ENRTF). Melissa A. Maurer-Jones was funded through Minnesota's Discovery, Research, and InnoVation Economy (MnDRIVE). The authors would like to acknowledge Magdalene Jones and Jonathan Tigner for taking DSC measurements. Parts of this work were carried out in the Characterization Facility, University of Minnesota, which receives partial support from the National Science Foundation through the Materials Research Science and Engineering Centers (MRSEC) program.

Publisher Copyright:
© 2023

Keywords

  • Degradation
  • Plastic films
  • Prior irradiation
  • Sewage sludge

MRSEC Support

  • Shared

PubMed: MeSH publication types

  • Journal Article

Fingerprint

Dive into the research topics of 'Sewage sludge induces changes in the surface chemistry and crystallinity of polylactic acid and polyethylene films'. Together they form a unique fingerprint.

Cite this