Chemistry Reference
In-Depth Information
with the syndiotactic polymer.
313
Other vinyl polymers have included
acrylics,
314 -315
poly(vinyl chloride),
316
polypropylene,
317
ethylene-propyl-
ene-diene monomer elastomers,
318
and ethylene-octene copolymers.
319
Other studies have focused on poly(dimethylsiloxane) blended with
polycarbonates,
320-322
polyisobutylene,
323
poly(ethylene oxide),
324
polyure-
thanes,
325
epoxies,
326-327
benzoxazines,
328-329
and poly(hexylthiophene).
330
In some cases, a polysiloxane oil was blended into polypropylene to facili-
tate its processing.
331
A variety of other siloxane materials have been
employed—for example, poly(diethylsiloxane),
332
polyurethanes,
333
fluori-
nated siloxane copoymers
334
and fluororubbers in general,
335
and trimethyl-
siloxy silicates.
336
3.6.2 Ceramic Phases and Coatings
Pyrolyses of siloxane materials leads to ceramic-like phases. For example,
ceramic fibers based on silicon carbide have been prepared from polycar-
bosilane/polymethylphenylsiloxane polymer blends.
337
PDMS coatings have been made less oleophobic by modifying them
using copolyacrylate side chains some of which are semifluorinated or
PDMS itself.
338
Also relevant here are UV-curable bismaleimides contain-
ing PDMS as hydrophobic agents.
339
3.6.3 Micropatterned Materials
PDMS emerged as the polymer of choice for micropatterned surfaces
and microfluidic devices. Fabrication is particularly straightforward
since PDMS can be cast against a suitable mold with high fidelity. The
optical, thermal, interfacial, permeability, and reactivity properties of
PDMS make possible numerous functionalities including optical detec-
tion, reversible deformation, reversible wetting, and management of
cell proliferation.
340
3.6.4 Nanofilaments and Molecular Wires
Metallic nanowires with vertical alignment have been prepared on
silicone substrates using a nanoporous alumina template.
341
The fact
that the substrate is flexible should be an advantage in a number of
applications.
