Characterization of degradation fragments released by arc-induced ablation of polymers in air
2016 (English)In: Journal of Physics D: Applied Physics, ISSN 0022-3727, E-ISSN 1361-6463, Vol. 49, no 5, 055502Article in journal (Refereed) PublishedText
Polymers exposed to high intensity arc plasmas release material in a process called arc-induced ablation. In order to investigate the degradation fragments released due to this process, two different polymeric materials, poly(oxymethylene) copolymer (POM-C) and poly(methyl methacrylate) (PMMA), were exposed to a transient, high-power arc plasma in air. A small fraction of the ablated material drifting away from the arcing volume was deposited on a fixed glass substrate during the total duration of a 2 kA ac current semicycle. In addition, another fraction of the released material was deposited on a second moving substrate to obtain a time-resolved streak 'image' of the arc-induced ablation process. For the first time, mass spectra of degradation fragments produced by arc-induced ablation were obtained from the material deposited on the substrates by using laser desorption ionization time-of-flight mass spectrometry (LDI-ToF-MS). It was found that oligomers with mean molecular weight ranging between 400 and 600 Da were released from the surface of the studied polymers. The obtained spectra suggest that the detected degradation fragments of POM could be released by random chain scission of the polymer backbone. In turn, random chain scission and splitting-off the side groups are suggested as the main chemical mechanism leading to the release of PMMA fragments under arc-induced ablation.
Place, publisher, year, edition, pages
Institute of Physics Publishing (IOPP), 2016. Vol. 49, no 5, 055502
arc plasma, polymer ablation, degradation, laser desorption ionization time-of-flight mass spectrometry
IdentifiersURN: urn:nbn:se:kth:diva-182768DOI: 10.1088/0022-3727/49/5/055502ISI: 000368944100029ScopusID: 2-s2.0-84957570081OAI: oai:DiVA.org:kth-182768DiVA: diva2:906102
QC 201602232016-02-232016-02-232016-02-23Bibliographically approved