Toolbox for dispersing carbon nanotubes into polymers to get conductive nanocomposites

The three main strategies for dispersing carbon nanotubes (NTs) into a polymer matrix to get conductive nanocomposites are described, and illustrated with some appealing examples. The direct mixing of the NTs and the polymer is the 'simplest' concept to achieve this goal. Other approaches concern the modification of either the polymer matrix or the NT walls in order to improve the wetting of the filler with the matrix material, and thus promote the incorporation of the NTs into the polymer matrix. Most promising results seem to be obtained upon the addition of a third component. The basic concept is the generation of a stable colloidal system containing both a suspension of NTs stabilized by surfactant molecules in water, and polymer latex. After removal of the water, the resulting powder can be processed into the desired shape. This versatile and environmentally benign concept offers low percolation thresholds and relatively high conductivity levels.