The name is absent

9

disperse CNTs into metal [30] and polymer [31]matrices, respectively. While many
have reported success with such procedures, there still exist concerns about the
survivability of the CNTs through such forceful methods [32].

Due to their gas permeability, another option for increased homogeneity
specifically in polymer matrices is through the use of surfactants; by lowering the
viscosity of the matrix through the "lubrication” of the polymer chains, the CNTs are
able to more-easily intercalate and spread homogeneously throughout the matrix.
Gong et al. were the first to report solvent addition to this end for CNT composites
[33], where they reported that the composite prepared with a solvent had a much
more significant shift in the glass transition (T_g) and a 30% increase in the elastic
modulus as compared to the traditionally-prepared control. They did note,
however, that agglomeration of the CNTs was still an issue. Over the following
decade, the use of solvents has become a favored technique for the manufacturing of
randomly-dispersed nanocomposites due to the ease of solvent removal after
dispersion has taken place.

1.3.2, Self-Assembly of CNTs to Achieve Composite Homogeneity

As it can be very difficult to break apart aggregates and then evenly disperse
nanoscale constituents in a matrix, a more favorable technique would be to organize
the CNTs prior to introducing the polymer. This was, in fact, the technique used in
the early days of CNT composite study, where randomly-aligned films of CNTs were
created through the dispersion in a solvent and subsequent filtering or evaporation
[28]. While this does provide a backbone for a two-dimensional composite film, the

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