Abstract
Tailoring Vertically-Aligned Carbon Nanotube Growth for
Poly(dimethylsiloxane)-Infιltrated Nanoconiposites
by
Brent Carey
This thesis discusses the viability of the polymer infiltration nanocomposite
preparation technique for aligned carbon nanotubes (A-CNTs) as produced by two
methods: pre-deposited catalyst chemical vapor deposition (CVD), and vapor-phase
CVD. Both types of growth furnaces were constructed, and the resultant A-CNT
"forests” were impregnated with poly(dimethylsiloxane), a highly-compliant
silicone elastomer. The survivability of the CNT alignment subsequent to the
polymer infiltration was studied for the respective nanocomposites, and it was
observed that the thin-walled CNTs produced by the pre-deposited catalyst CVD
method were not robust enough to maintain alignment during the infiltration, in
contrast to the thicker-walled vapor-phase-grown CNTs. The dynamic mechanical
properties of the successfully-impregnated composites were then studied, and their
strain- and frequency-dependent behavior was probed both transverse and
longitudinal to the alignment direction of the CNTs, revealing distinct responses due
to their anisotropy.