Advanced Techniques for Nanocharacterization of Polymeric Coating Surfaces.
Advanced Techniques for Nanocharacterization of
Polymeric Coating Surfaces.
Gu, X.; Nguyen, T.; Sung, L. P.; Ho, D. L.;
Vanlandingham, M. R.; Jean, Y. C.; Martin, J. W.
Federation of Societies for Coatings Technology (FSCT)
Technical Program Annual Meeting, 81st. November 12-14,
2003, Philadelphia, PA, Federation of Societies for
Coatings Technology, Blue Bell, PA, 2003.
coatings; polymer coating surface; uv degradation;
nanoindentation; characterization; nanoscale
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.