Mapping Heterogeneity in Polymeric Materials Using Atomic Force Microscopy: Phase Imaging and Nanoindentation.
Mapping Heterogeneity in Polymeric Materials Using
Atomic Force Microscopy: Phase Imaging and
Gu, X.; VanLandingham, M. R.; Raghavan, D.; Nguyen, T.
Polymeric Materials: Science and Engineering (PMSE).
Spring Meeting. Volume 82. Proceedings. American
Chemical Society (ASME). March 26-30, 2000, San
Francisco, CA, American Chemical Society, Washington,
DC, 50-51 pp, 2000.
microscopy; coatings; degradation; heterogeneity;
nanoindentation; phase imaging
Polymer coatings are heterogeneous and often contain
nanoscale degradation susceptible regions. Therefore,
mapping and identification of these regions would
provide essential information for understanding the
mechanism of the degradation of polymeric coatings. A
combination of phase imaging and nanoindentation in
tapping mode FM has emerged as a powerful technique to
provide direct mapping of surface morphology and
identification of surface heterogeneity with nanometer
resolution. The application of this technique for
studying heterogeneity of unannealed and annealed
poly(methyl methacrylate)/polybutadiene blends has been
investigated. The effects of force level and annealing
time on the phase image contrast and force curves are
discussed. The results show that this combined technique
can provide data to distinguish nano- and micro-scale
heterogeneous domains in the blend films. The use of
this technique for studying heterogeneity in a polyester
film exposed to an alkaline solution is also presented.