Treatment of poly(ether ether ketone) (PEEK) surfaces by remote plasma discharge. XPS investigation of the ageing of plasma‐treated PEEK

The effect of a cold remote N 2 plasma (CRNP) or N 2 + O 2 plasma (CRNOP) on poly(ether ether ketone) (PEEK) is studied. The amount of nitrogen or oxygen uptake and functionalities are determined by x‐ray photoelectron spectroscopy (XPS). After CRNP treatment, the N/C and O/C atomic ratios are 0.301 and 0.333, respectively. Nitrogen functional groups are not detected by CRNOP treatment, and the O/C atomic ratio is then 0.785. The ageing process of the treated PEEK surface in the open air is investigated in both cases. For CRNOP treatment the O/C atomic ratio decreases by carbonate function departure, whereas for CRNP treatment the total amount of nitrogen and oxygen graft atoms goes through a maximum after 1 h of air exposure.