XPS STUDIES OF THE OXYGEN-1S AND OXYGEN-2S LEVELS IN A WIDE-RANGE OF FUNCTIONAL POLYMERS

Over 70 oxygen-containing polymers have been studied using high-resolution monochromated XPS. O 1s binding energies (BEs) are reported and compared with previous data from much smaller sample sets. The separation of the two components from O-C=O groups is quite sensitive to structural variation. O 1s peak widths and the effect of shake-up on peak areas are also discussed. For about a representative one-third of these polymers the O 2s region of the valence band has been studied in detail. O 2s BEs are reported and a new parameter is introduced: the O 1s-O 2s energy separation (oxygen valence parameter). This parameter has a greater range than the O 1s chemical shift, is independent of any surface charging, and appears to have interesting diagnostic potential. The origins of multiplet structures sometimes observed in the O 2s region are discussed in terms of simple MO theory.