Surface corrosion of polytetrafluoroethylene (PTFE) based microwave digestion vessels was monitored by reflection FTIR and FT-Raman techniques. Samples were taken from digestion vessels after 0 (new), 50, 100, and 200 digestion cycles of milk powder. The spectrum of the new (unused) sample was subtracted from the spectra of used vessels in order to identify small differences, e.g., surface degradation or modification, between the samples. The new IR features of CF2 and CF3 groups for PTFE samples at 1197, 1139, and 642 cm-1 refer to surface modification (degradation) of the polymer chain. Special surface species, such as aliphatic hydrocarbons, inorganic nitrates and FNO3, were identified. The Raman spectra of PTFE samples also showed formation of new CF3 groups, indicating that the polymer chain (or side chain) was changed (shortened) after different cycles.
|Number of pages||5|
|Journal||Croatica Chemica Acta|
|Publication status||Published - Dec 1 2006|
- FTIR micro ATR
- Surface degradation
- Teflon digestion vessel
ASJC Scopus subject areas