Surface functionalization of PEEK films studied by time-of-flight secondary ion mass spectrometry and x-ray photoelectron spectroscopy

The Surface Characterisation of Polyetheretherketone (PEEK) Modified via the Direct Sputter Deposition of Calcium Phosphate Thin Films

“…According to Pawson et al [28], peaks below m/z 60 within the negative survey have not been found to be useful diagnostically and intensities are low, which, from looking at other literature, was expected. Work by Henneuse-Boxus et al [27] has detailed a number of peaks for the m/z ratios of PEEK fragments which have been found within the negative survey presented here, these included 25, 41, 49, 73, 108, 121, and 196, which were recorded as corresponding to C 2 H − , C 2 OH − , C 4 H − , C 6 H − , C 6 H 4 O 2 − , C 7 H 5 O 2 − and C 13 H 8 O 2 − , respectively. The peak at the m/z ratio of 197 has been assigned to the PEEK monomer.…”

“…The surface maps for m/z 108, 121, and 196 have been associated with aromatic polymers or fragments of PEEK [27], it was expected that these would be present in a higher intensity than they were found, in comparison to a modified surface. C n H m clusters were observed in much higher intensities than the peaks chosen (m/z 108, 121, and 196) and are known as attributable to carbonaceous species, these have been thought of as generally indicative of a polymeric material; however, these were considered too generic to utilise on this occasion as, according to literature, they have not been considered diagnostic of PEEK [28].…”

“…The negative ion survey of the CaP thin films sputter deposited onto the PEEK surface for up to 10 min in the m/z 20-100 range is shown in Figure 11b, with characteristic peaks within the spectra noted at an m/z 63 and 79 corresponding to PO2 − and PO3 − . Peaks were also observed at 25, 41, 49, and 73, corresponding to the main negative fragments of PEEK, C2H − , C2OH − , C4H − and C6H − [27], these have been attributed to either PEEK or surface contamination due to their exposure to atmospheric conditions. Similar results were observed for figure the positive and negative ion spectra for the HA600 sample, as shown in Figure 12a,b, respectively.…”

“…The O 1s envelope ( Figure 4a) revealed two peaks, the most intense peak attributable to the ether, O-C group, at 533.2 eV (O2) (73%) whilst the peak located at 531.1 eV (O1) was found to be indicative of the carbonyl group, C=O, (27%) [25,26]. The C 1s core level spectrum, as shown in Figure 4b has been peak fitted using four peaks, of which the highest intensity peak has been noted at 285.0 eV (C1), C-H and C-C bonds [27][28][29]. A further peak was noted at 286.6 eV (C2) which is known to correspond to the binding of C and O atoms, C-O ether bonding.…”

“…In order to determine the presence or otherwise of particular chemical species, ToFSIMS was employed to provide information about the chemical nature of the outermost molecular layer (1-10 Å) of the PEEK and CaP modified PEEK (HA10, HA300 and HA600) samples via a mass survey. Given the high mass resolution of SIMS it was particularly well suited to polymer surface analysis; however, the analyses of PEEK via ToFSIMS has been scarcely described within the literature [27,28]. The positive and negative ion spectra for the PEEK polymer have been acquired in the relevant m/z ranges of 0-200.…”