R. Bongiovanni et al., High resolution XPS investigation of photocured films containing perfluoropolyether acrylates, POLYMER, 41(2), 2000, pp. 409-414
The paper reports an XPS investigation on films obtained by photopolymerisi
ng new perfluoropolyether methacrylates as pure products or added in low am
ounts to a typical UV-curable resin (Bisphenol A bis-ethylether diacrylate)
. The structure of the fluorinated monomers is Rf-Rh type, where Rh = -CH2O
-CO-NH-CH2-CH2-OCOC(CH3) = CH2 while Rf = CF3-CF2O-(CF2O)(n)(CF2-CF2O)(m)-C
F2- for monomer 1 (PM 890, m/n = 1.68), and Rf = Cl-CF2-CF(CF3)-O-(CF2CF(CF
3)-O)(2)-CF2- for monomer 2. Quantitative evaluation of the different atomi
c ratios was performed using take-off angles of 45 and 10 degrees (very sur
face region) on both film sides, the one in contact with the glass substrat
e and the one exposed to air. The results obtained indicate strong fluorine
enrichment on the air side of the films and a concentration gradient at th
e surface, while the glass side has a composition similar to the bulk. (C)
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