Comparison of static secondary ion mass spectrometry, ion scattering spectroscopy, and x-ray photoelectron spectroscopy for surface analysis of acrylic polymers

The comparison of three surface analytical tools, static secondary Ion mass spectrometry (SIMS), Ion scattering spectroscopy (ISS), and X-ray photoelectron spectroscopy (XPS or ESCA), Is presented. Information available from ISS and ESCA Is Illustrated by comparing plots of carbon/oxygen Intensity ratio vs. monomer composition for both methods. Both ESCA and ISS yield linear correlations, ESCA having the higher correlation coefficient. The ISS plot had some deviations which could not be explained by sterlc effects alone. Static SIMS results were Interpreted by using a “backbone/slde chain” model of polymer structure which explains Ions generated from bond breaking along the hydrocarbon backbone and the pendant side chain functionality which Is varied In the polymer series of poly(methacrylates). Positive Ion spectral patterns are Interpreted for short chain alkyl, Isomeric butyl, and cyclic and long chain alkyl functionalities.