ToF-SIMS Depth Profiling of a Complex Polymeric Coating Employing a C60 Sputter Source
نویسندگان
چکیده
A complex poly(vinylidene difluoride) (PVdF)/poly(methyl methacrylate) (PMMA) based coil coating formulation has been investigated using time-of-flight SIMS (ToFSIMS). Employing a Bi3 + analysis source and a Buckminsterfullerene (C60) sputter source, depth profiles were obtained through the polymeric materials in the outer few nanometres of the PVdF topcoat. These investigations demonstrate that the PVdF coating’s air/coating interface is composed principally of the flow agent included in the formulation. Elemental depth profiles obtained in the negative ion mode demonstrate variation in the carbon, oxygen and fluorine concentrations within the coating with respect to depth. All 3 elemental depth profiles suggest that the PVdF coating bulk possesses a constant material composition. The oxygen depth profile reveals the presence of a very thin oxygen rich sub-surface layer in the PVdF coating, observed within the first second of the sputter/etch profile. Retrospectively extracted mass spectra (from the elemental depth profile raw data set) of the PVdF coating subsurface and bulk layers indicates this oxygen rich sub-surface layer results from segregation of the acrylic co-polymers in the formulation towards the PVdF coating air/coating interface. Molecular depth profiles obtained in both the positive and
منابع مشابه
C60 molecular depth profiling of a model polymer
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