RF-CF4 Plasma Treatment of Tetrafluoroethane Pre-deposited Paper, Part 1: Hypotheses on Surface Reactions.

CF4 plasma treatment of a Teflon-like (1,1,1,2 tetrafluoroethane, TFE) chemical spray deposited on paper resulted in an increased level of elemental fluorine on the paper surface. However, TFE molecules undergo bond cleavage and ionization in the presence of the RF-CF4 plasma environment. The abundant fluorine radicals grafted onto the paper surface, via the substitution and opening of the bonds in the cellulose polymers, yielded CFx (x: 1–3) functionalities, as observed by XPS and ATR-FTIR analyses. Lower power (100 W) and treatment times (0.5 min) were sufficient to obtain very highly fluorinated surfaces. The change in the morphology of the surface by the exposure to plasma was complicated because the localized deposition and re-deposition of the plasma-generated molecules on the paper were superimposed on the surface reactions and degradation (etching) at the paper surface. [ABSTRACT FROM AUTHOR]