Please be advised that the site will be down for maintenance on Sunday, September 1, 2024, from 08:00 to 18:00, and again on Monday, September 2, 2024, from 08:00 to 09:00. We apologize for any inconvenience this may cause.
dc.contributor.author | Venner, W.V. (Victor) | |
dc.contributor.author | Puts, Gerard Jacob | |
dc.contributor.author | Crouse, Philippus L. | |
dc.date.accessioned | 2018-12-12T11:24:35Z | |
dc.date.issued | 2019-01 | |
dc.description.abstract | PTFE homopolymer synthesised using ammonium persulfate initiator discolours at sintering temperatures of approximately 380 °C. No report on this phenomenon is available in the open literature. To shed light on the problem, PTFE samples were synthesised using various initiators and different pH buffers. The initiators used included ammonium persulfate, sodium persulfate, potassium permanganate, di-tertiary butyl peroxide and hydrogen peroxide. Borax and potassium carbonate were used as the buffering agents. The samples were pressed into discs and sintered at 380 °C. The samples were analysed using FTIR and Raman spectroscopy to determine the influence of decomposition of the end-groups during sintering. Each initiator resulted in unique end-groups, with a suggestion of multiple termination reactions in several of the samples. The discolouration of the samples occurs because of amorphous carbon deposition into the polymer matrix after elimination from the end-groups during sintering. The level of discolouration is dependent on the type and concentration of initiator used. | en_ZA |
dc.description.department | Chemical Engineering | en_ZA |
dc.description.embargo | 2020-01-01 | |
dc.description.librarian | hj2018 | en_ZA |
dc.description.uri | http://www.elsevier.com/locate/fluor | en_ZA |
dc.identifier.citation | Venner, W.V., Puts, G.J. & Crouse, P.L. 2019, 'Influence of initiators on the sintering discolouration of PTFE', Journal of Fluorine Chemistry, vol. 217, pp. 63-71. | en_ZA |
dc.identifier.issn | 0022-1139 (print) | |
dc.identifier.issn | 1873-3328 (online) | |
dc.identifier.other | 10.1016/j.jfluchem.2018.10.017 | |
dc.identifier.uri | http://hdl.handle.net/2263/68094 | |
dc.language.iso | en | en_ZA |
dc.publisher | Elsevier | en_ZA |
dc.rights | © 2018 Elsevier B.V. All rights reserved. Notice : this is the author’s version of a work that was accepted for publication in Journal of Fluorine Chemistry. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. A definitive version was subsequently published in Journal of Fluorine Chemistry, vol. 217, pp. 63-71, 2019. doi : 10.1016/j.jfluchem.2018.10.017. | en_ZA |
dc.subject | Poly(tetrafluoroethylene) (PTFE) | en_ZA |
dc.subject | Tetrafluoroethylene (TFE) | en_ZA |
dc.subject | PTFE discoloration | en_ZA |
dc.subject | TFE polymerisation | en_ZA |
dc.subject | PTFE radical initiators | en_ZA |
dc.subject | Polymer end-groups | en_ZA |
dc.title | Influence of initiators on the sintering discolouration of PTFE | en_ZA |
dc.type | Postprint Article | en_ZA |