A spectroscopic study on defluorination of poly(tetrafluoroethylene) by alkyllithium/electron-donating solvents
Yasuhiro Okuda1, Fumihiro Hayashi, Hiroshi Sakurai
1Electronics & Materials R&D Laboratories, Sumitomo Electric Industries Ltd, 1-1-3 Shimaya, Konohana-Ku, Osaka 554-0024, Japan. okuda-yasuhiro@sei.co.jp
Abstract:
Defluorination of PTFE by alkyllithium/electron-donating solvents such as N,N,N',N'-tetramethylethylenediamine (TMEDA), hexamethylphosphoramide (HMPA) was studied by means of spectroscopy such as ESR, 7Li- and 13C-NMR, XPS, UV-Vis and IR. Based on the experimental results, it was concluded that an electron from radical species, which was generated in the alkyllithium/electron-donating solvent, was transferred onto PTFE molecule so as to eliminate fluorine atoms from the PTFE and to form carbon-centered radicals on the PTFE; concomitantly, the alkyl group of the alkyllithium was transferred onto the PTFE. Combined with the experimental results of the phenyllithium/HMPA system, mechanism of the fluorine atom elimination reactions from PTFE by the radical species is discussed.
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