Tailoring vertically-aligned carbon nanotube growth for poly(dimethylsiloxane)-infiltrated nanocomposites

摘要

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.