Titlebar

Export bibliographic data
Literature by the same author
plus on the publication server
plus at Google Scholar

 

Quantification of photooxidative defects in weathered microplastics using ¹³C multiCP NMR spectroscopy

Title data

Mauel, Anika ; Pötzschner, Björn ; Meides, Nora ; Siegel, Renée ; Strohriegl, Peter ; Senker, Jürgen:
Quantification of photooxidative defects in weathered microplastics using ¹³C multiCP NMR spectroscopy.
In: RSC Advances. Vol. 12 (7 April 2022) Issue 18 . - pp. 10875-10885.
ISSN 2046-2069
DOI: https://doi.org/10.1039/D2RA00470D

Project information

Project title:
Project's official titleProject's id
SFB 1357 Mikroplastik391977956

Project financing: Deutsche Forschungsgemeinschaft
Open Access Publishing Fund of the University of Bayreuth

Abstract in another language

Weathering of microplastics made of commodity plastics like polystyrene, polypropylene and polyethylene introduces polar polymer defects as a result of photooxidation and mechanical stress. Thus, hydrophobic microplastic particles gradually become hydrophilic, consisting of polar oligomers with a significant amount of oxygen-bearing functional groups. This turnover continuously changes interactions between microplastics and natural colloidal matter. To be able to develop a better understanding of this complex weathering process, quantification of the corresponding defect proportions is a first and essential step. Using polystyrene, 13C enriched at the α position to 23%, we demonstrate that 13C cross polarisation (CP) NMR spectroscopy allows for probing the typical alcohol, peroxo, keto and carboxyl defects. Even the discrimination between in- and end-chain ketones, carboxylic acids and esters as well as ketal functions was possible. Combined with multiCP excitation, defect proportions could be determined with excellent accuracy down to 0.1%. For materials with 13C in natural abundance, this accounts for a detection limit of roughly 1%. The best trade-off between measurement time and accuracy for the quantification of the defect intensities for multiCP excitation was obtained for CP block lengths shorter than 250 μs and total build-up times longer than 2 ms. Further measurement time reduction is possible by using multiCP excitation to calibrate intensities obtained from series of 13C CP MAS NMR spectra. As photooxidation is an important degradation mechanism for microplastics in the environment, we expect these parameters to be transferable for probing defect proportions of weathered microplastics in general.

Further data

Item Type: Article in a journal
Refereed: Yes
Institutions of the University: Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Inorganic Chemistry III > Chair Inorganic Chemistry III - Univ.-Prof. Dr. Jürgen Senker
Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Macromolecular Chemistry I > Chair Macromolecular Chemistry I - Univ.-Prof. Dr. Hans-Werner Schmidt
Research Institutions > Research Centres > Nordbayerisches Zentrum für NMR-Spektroskopie - NMR-Zentrum
Research Institutions > Collaborative Research Centers, Research Unit > SFB 1357 - MIKROPLASTIK
Faculties
Faculties > Faculty of Biology, Chemistry and Earth Sciences
Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry
Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Inorganic Chemistry III
Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Chair Macromolecular Chemistry I
Research Institutions
Research Institutions > Research Centres
Research Institutions > Collaborative Research Centers, Research Unit
Result of work at the UBT: Yes
DDC Subjects: 500 Science
500 Science > 540 Chemistry
600 Technology, medicine, applied sciences > 620 Engineering
Date Deposited: 25 Apr 2022 11:26
Last Modified: 29 Apr 2022 10:02
URI: https://eref.uni-bayreuth.de/id/eprint/69336