Mapping Chemically Heterogeneous Polymer System Using Chemical Modification and Atomic Force Microscopy.
Mapping Chemically Heterogeneous Polymer System Using
Chemical Modification and Atomic Force Microscopy.
(619 K)
Raghavan, D.; Gu, X.; VanLandingham, M. R.; Nguyen, T.
ACS Polymer Preprints, Vol. 41, No. 2, 1423-1424, 2000.
Keywords:
mapping; microscopy; coatings; degradation;
heterogeneity; nanoindentation; phase imaging; polymers
Abstract:
The objective of this study was to demonstrate an
approach to map a chemically heterogeneous system using
chemical modification and Tapping Mode Atomic Force
Microscopy (TMAFM). This approach is based on selective
degradation of one of the phases in a two-phase polymer
blend system and the ability of TMAFM to provide
nanoscale lateral information about the different phases
in heterogeneous polymer system. A 70:30 PEA/PS blend
was exposed to a hydrolysis environment and analyzed
using TMAFM. Based on the TMAFM results, which show
similar degradation patterns between the pure PEA film
and the matrix of the PEA/PS blend, the domains in the
blend were identified as the PS-rich regions and the
matrix as the PEA-rich region. These results are
substantiated by AFM force curve measurements and
FTIR-ATR analysis of the hydrolyzed PEA and PEA/PS
samples. The usefulness of this approach in
understanding the degradation process of a coating film
will be discussed.
Building and Fire Research Laboratory
National Institute of Standards and Technology
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