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 (similar to80 cm(-1)), appearance of ester oxygen in the XPS spectra, as well as by the F-19 nmr spectra of volatile products consistent with a terminal NF2 group. (C) 2004 Elsevier B.V. All rights reserved.