Effect of Preparation Method on the Electrical and Mechanical Properties of PVC/Carbon Nanotubes Nanocomposites

The biggest challenge for the development of carbon nanotubes polymeric nanocomposites is in the suitable dispersion and distribution of the nanometric particles along the polymer matrix. Several preparation methods have been used to obtain nanocomposites, highlighting the mixture with polymer solution followed by solvent evaporation and the hot compacting. The first one has the advantage of allowing dispersion of the nanotubes in a low viscosity medium, while the second method is more environmental favorable due to reduced use of solvent. The aim of this work was to evaluate the influence of the preparation method on the electrical resistivity of PVC/carbon nanotubes nanocomposites, containing from 0.05 to 1.00%w of carbon nanotubes. The results showed a percolation threshold of 0.4%w and 0.15%w of nanotubes for the polymer solution method and hot compacting, respectively, and an electrical resistivity reduction of eight and nine orders of magnitude, respectively, compared to pure PVC. The tensile strength of PVC/MWNT nanocomposites was not affected by the presence or content of carbon nanotubes compared to PVC without addition of nanoparticles, regardless of the material preparation method, however the deformation at beak was largely reduced.