Reactions of amide group with fluorine as revealed with surface analytics

Thin polyamide-6 films were exposed to fluorine gas and analysed with photoelectron and infrared spectroscopies. Fluorine cleaves the amide C–N bond resulting in the formation of the –COOH and –NF2 terminal groups. This is evident from large shifts in the N1s binding energy (+5 eV) and CO stretching frequency (∼80 cm−1), appearance of ester oxygen in the XPS spectra, as well as by the 19F nmr spectra of volatile products consistent with a terminal NF2 group.