Chemistry Reference
In-Depth Information
glass substrates.
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A related study involved nanoviscosity of PDMS as
measured by an anthracene probe.
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6.3.4 Surface Pressure
The relationships between surface pressure and surface or interfacial area
can be used to gauge hydrophilicity. This method has been used, for exam-
ple, to quantify the hydrophilicity of PDMS modified with ethylene oxide
or propylene groups.
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6.3.5 Atomic Force Microscopy
Atomic force microscopy has been combined with nano-indentation mea-
surements to map hardness variations on the surface of a CaCO
3
-illed
sample of PDMS.
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In another application, PDMS-modified tips were used
to obtain friction coefficients involving self-assembled monolayers.
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6.3.6 Nuclear Magnetic Resonance
A relevant example in this area involves self-diffusion measurements in a
microemulsion consisting of water, oil, and ethoxylated polymethylsilox-
ane surfactant.
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6.3.7 Swelling
Surface modification of PDMS has been used to retard swelling in organic
solvents, which is particularly important for fabricating microfluidic de-
vices and for some types of lithography.
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6.3.8 Exposure to Seawater
PDMS has been widely used in antifouling coatings where it receives
extensive exposures to seawater. The nature and extent to which the
PDMS surface was modified can be determined in a variety of ways,
including scanning electron microscopy and x-ray photoelectron
spectroscopy.
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