| AVS 63rd International Symposium & Exhibition | |
| Applied Surface Science | Wednesday Sessions |
| Session AS-WeA |
| Session: | Multiple Technique Approaches for Real-World Industrial Problem Solving |
| Presenter: | Jorge Bañuls Ciscar, University of Surrey, UK |
| Authors: | J. Bañuls Ciscar, University of Surrey, UK M.L. Abel, University of Surrey, UK J.F. Watts, University of Surrey, UK |
| Correspondent: | Click to Email |
Polymeric methyl diphenyl diisocyanate (p-MDI) is a versatile isocyanate commonly used in coatings and adhesives applications because of its excellent mechanical properties. In this work, we are aiming to understand the chemistry involved at the interface between p-MDI and a specific stainless steel as a result of different processing parameters. This steel has distinct surface properties. On one side the surface has been ground and the composition is mostly iron oxide (Fe2O3) whereas on the other side the steel has a mill-finished surface and the composition is predominantly chromium oxide (Cr2O3). Therefore, in our system of interest, the stainless steel has different physical and chemical properties on each side. As such, understanding the adhesion aspects of p-MDI on each side could lead to an improvement of its use in many steel applications.
Preliminary work using XPS and ToF-SIMS has shown an interaction between nitrogen and chromium oxide at the interface. A low binding energy peak ( ̴397 eV) was identified in the N1s high resolution XPS spectrum. This peak represents nitrogen atoms which have a higher electronic density as a result of the electron withdrawing effect of the MDI on the metal substrate. Additionally, peaks of characteristic fragments of N-Cr interaction were found in the ToF-SIMS spectra. This will form the basis of further work to determine the exact chemistry involved in such interfacial regions.