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true challenge is in organizing CNTs three-dimensionally. Such a feat is no trivial
task, as it is not physically feasible to organize such a large number of individual
CNTs. As such, the only viable way to achieve such spatial organization is through
self-assembly.
As mentioned in Section 1.2.2, CVD can be used to grow vertically-aligned
arrays of CNTs whose spacing and orientation are predefined by the growth
conditions. In contrast to the typical method of introducing CNTs to a polymer, the
success of this method lies in introducing the polymer to these already-oriented
CNT arrays. This technique of polymer infiltration was first explained in-depth in
2005 through the infiltration of methyl methacrylate prior to polymerization [34].
Assuming there is sufficient surface interaction (wetting] between the CNTs and the
desired matrix (a surface wetting study between CNTs and many common matrix
polymers is given in a report by Barber et al. [35]), this method of composite
preparation is as trivial as infiltrating the aligned forest with the matrix polymer
prior to crosslinking (for curable polymers), with or without the use of a solvent. A
similar polymer infiltration method was the technique used for this thesis work, and
specific details are given in Section 3.1.
1.4. Research Motivations
While there has been much research on the development of CNT-reinforced
composites, there are still very significant issues with agglomeration and dispersion.
This is particularly true for very-large-aspect-ratio CNTs, which become virtually