Abstract
The interaction between poly(methyl methacrylate) (PMMA) and oxidized aluminium surfaces has been studied using Fourier transform infra-red multiple specular reflectance ( FTi.r.-MSR) and inelastic electron tunnelling spectroscopy (IETS). FTi.r.-MSR spectra of ultra thin (∼1 nm) PMMA films show an enhancement of the intensity in the low frequency wing of the carbonyl absorption. The peak is shifted to lower frequency and broadened compared to theoretical predictions. This suggests hydrogen bonding between the PMMA carbonyl species and the surface hydroxyl groups. The relative intensity of the carbonyl mode in the IETS spectrum is very low and its frequency is lowered compared to the i.r. result. In addition, a small band is observed at the position of the v s(CO − 2) vibration. However, ester bond cleavage and subsequent formation of ionic carboxylate bonds is very unlikely, because it contradicts the FTi.r.-MSR results. This suggests an intrinsically low intensity of carbonyl bands in IETS. The inertness of the lead counter electrode in IETS is discussed. The lead electrode may account for the downward shift of the carbonyl vibration in IETS.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.