Synthesis and characterization of thickness-aligned carbon nanotube - polymer composite films

To optimize the properties of carbon nanotube-polymer composites, it is important to control nanotube dispersion and alignment, One way to achieve such control is by growing homogeneous, well-aligned arrays of carbon nanotubes using chemical vapor deposition and infiltrating polymer or monomer into the arrays, followed by in situ polymerization. In this paper, pre-aligned multiwalled carbon nanotube arrays were infiltrated with methyl methacrylate (MMA) and the MMA was polymerized. The resulting composite films have well-dispersed, aligned nanotubes. Using the Washburn technique, it was found that the infiltration of monomers into aligned nanotube arrays is largely driven by the wetting of liquids against the nanotube walls and the low viscosity of liquids. Once polymerized, the PMMA had higher thermal stability. This synthesis process is adaptable to various polymers. It is possible to combine conventional micro-patterning techniques with infiltration process for achieving selective infiltration of polymer across nanotube arrays. Thus, the present synthesis strategy has tremendous implications toward building some of the novel architectures with nanotubes and polymers, having unique properties. © 2005 American Chemical Society.