Use of Laser Scanning Confocal Microscopy for Quantitative Characterization of Physical Changes of Polymer Coatings After UV Exposure.
Use of Laser Scanning Confocal Microscopy for
Quantitative Characterization of Physical Changes of
Polymer Coatings After UV Exposure.
(848 K)
Sung, L. P.; Jasmin, J.; Gu, X.; Nguyen, T.; 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.
Keywords:
coatings; lasers; microscopy; exposure; atomic force
microscopy; degradation; film ablation; ablation;
Fourier Transform Infrared spectroscopy; laser scanning
confocal microscopy; morphology; surface roughness;
thickness measurement; ultraviolet exposure
Abstract:
Laser scanning confocal microscopy (LSCM) has become a
powerful tool for monitoring physical changes in
polymeric coatings following ultraviolet (UV) radiation
exposure. Physical changes caused by UV exposure include
film ablation, formation of pits and other surface
defects, and increases in surface roughness. The
physical changes as a function of exposure time were
compared to chemical degradation measured with Fourier
Transform Infrared (FTIR) spectroscopy. It was found
that after 400 h of UV exposure, film thickness changes
measured by LSCM were not correlated to the thickness
predicted by chemical degradation in an acrylic urethane
coating. Local physical changes (pit formation and
surface deformation) were observed that might contribute
to chemical changes.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899