Chemistry Reference
In-Depth Information
6.9.3 Tribology
The low coefficients of friction shown by the polysiloxanes have been
exploited in reducing abrasion or wear on a variety of materials. For
example, PDMS thin coatings on mica were studied in this regard.
167
PDMS block copolymers have been blended with polypropylene and
high-density polyethylene for this purpose.
168
Closely related is the
scratch resistance of elastomeric PDMS coatings on materials such as
stainless steel.
169
6.10 SOME NOVEL MATERIALS
6.10.1 Dendrimers
Dendrimers,
170 -173
including those based on organosilicon materials,
174
are
of great relevance in siloxane surface science, particularly since their sur-
faces have functionalities that are numerous and controllable.
6.10.2 Ceramic Phases and Coatings
Work in this area involves applying polysiloxane coatings on inorganic
substrates as has been done on silica,
175,
176
Al
2
O
3
/Ga As,
177
and the chan-
nels in microfluidic devices.
178
Variations include sol-gel blends of PDMS
and titania
179
and titania coatings on PDMS.
180
PDMS cores have also been
coated with poly(
N
-isopropylacrylamide) shells to give thermoresponsive
microspheres.
181
6.10.3 Micropatterning
Patterns with dimensions at the micron level have been placed on
PDMS
182, 183, 184
and PDMS-acrylic interfaces.
185
Such materials have nu-
merous applications, including soft lithography.
6.10.4 Nanofilaments and Molecular Wires
Polysiloxane nanofilaments can be superhydrophobic.
186
Such filaments
can be subsequently patterned to present a “superfunctional” surface.
187
Activation is achieved by an oxygen plasma followed by reaction with
