Quantifying amines in polymers by XPS

A method to identify and quantify amines in polymers by X-ray photoelectron spectroscopy using the energetic distribution of N1s atomic orbitals is presented in this work. The N orbital energetic states were obtained and associated with the atomic chemical states of amines through their formation energy. Pyrrole and allylamine plasma polymers were used as test polymers of this method because they potentially have primary, secondary and tertiary amines in their structure; although, additional unsaturated and oxidized amines were also found in the test polymers as a function of the synthesis power. The participation percentages of amines obtained with this method indicated that secondary amines had the greatest participation in the polymers followed by unsaturated and tertiary amines. The lowest participation belonged to primary amines or to the oxidized amines found during the analyses. This method is new and can be applied to other materials in solid state, not only to polymers, with enough stability to resist the X-ray beams of the XPS spectrometers.