Toolbox for Dispersing Carbon Nanotubes into Polymers To Get Conductive Nanocomposites

Abstract

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.

Graphene-philic surfactants for nanocomposites in latex technology

“…Studies on CNT/polymer nanocomposites have provided important pointers to make conductive nanocomposite systems using this type of polymer [69,70,[171][172][173].…”

Effects of silane functionalization on the properties of carbon nanotube/epoxy nanocomposites

“…The wrapping becomes more serious for well-dispersed individual CNTs. The wrapped polymer perturbs the π electron system of the CNT walls [19]. Secondly, the improved dispersion of CNTs in polymer matrix is known to be detrimental to the formation of electrical networks, especially at CNT contents above the percolation threshold.…”

Reducing defects on multi-walled carbon nanotube surfaces induced by low-power ultrasonic-assisted hydrochloric acid treatment

“…Compared with SWCNTs, MWCNTs are lower cost, better availability and always conductive, which make them attractive materials for fabricating conductive polymer-based composites [4][5][6]. It is worth pointing out that the electronic properties of the perfect MWCNTs are rather similar to those of the perfect SWCNTs, because the coupling between the cylinders is weak in MWCNTs [1].…”

“…Incorporation of nanotubes into polymer can potentially provide structural materials with dramatically increased modulus and strength [4][5][6]. Meanwhile, the low-loading levels and the nearly one-dimensional electronic structure of the MWCNTs allow improved conductivity to be achieved, while avoiding or minimising the deterioration of the original properties of polymer, such as mechanical properties and the low-melt flow viscosity needed for material processing.…”

“…The sp 2 structure of the nanotube would be interrupted at the defect sites and, consequently, the electronic properties of the graphene would be altered. To meet the requirement of nanotube functionalisation, chemical reaction occurring on the surface must be controlled in a particular manner to ensure chemical modification of nanotubes as well as their initial properties [4,5].…”