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Author
Gu, X. | Nguyen, T. | Sung, L. P. | Ho, D. L. | Vanlandingham, M. R. | Jean, Y. C. | Martin, J. W.
Title
Advanced Techniques for Nanocharacterization of Polymeric Coating Surfaces.
Coporate
National Institute of Standards and Technology, Gaithersburg, MD University of Missouri-Kansas City Army Research Laboratory, Aberdeen Proving Ground, MD
Book or Conf
Federation of Societies for Coatings Technology (FSCT) Technical Program Annual Meeting, 81st. November 12-14, 2003, Federation of Societies for Coatings Technology, Blue Bell, PA, Philadelphia, PA, 2003
Keywords
coatings | polymer coating surface | uv degradation | nanoindentation | characterization | nanoscale
Identifiers
tapping mode AFM
Abstract
The applications of AFM and nanoindentation on study of surface property of polymeric coatings have been demonstrated. The surface microstructure of several coatings was characterized using tapping mode AFM, and the morphological change of coatings during degradation was monitored with the exposure time. The results have shown that tapping mode AFM is a powerful technique for coating characterization with nanometer resolution because it can not only provide direct spatial mapping of surface topography, but also provide nanoscale microstructural information that reflects the property differences of heterogeneous coating materials. The capability of AFM on chemical heterogeneity imaging was also investigated. A small volume humidity chamber was used to control the tip and sample environment. The results have shown that the phase contrast between the hydrophilic regions and the hydrophobic areas can be enhanced by increasing the humidity of the environment, thus the sensitivity of AFM on surface chemical heterogeneity would be improved with the aid of the humidity chamber. Further, the application of nanoindentation instrument on the studies of surface mechanical properties, such as modulus, hardness and scratch resistance was also shown. It is believed that information from these nanoscal characterizations would be constructive for a better understanding on coating degradation mechanism, and therefore improving the service life performance of polymeric coatings.