Rheological properties and electrical conductivity of irradiated MWCNT/PP nanocomposites

Novel rheological features and conductivity results of irradiated PP/MWCNT nanocomposites are presented. Elongational flow measurements reveal a strain hardening behaviour which is compatible with the creation of long chain branched macromolecules provoked by irradiation. However, oscillatory shear flow results suggest that irradiation does not affect interactions of MWCNTs with PP chains. The addition of carbon nanotubes brings about conductivities of the order of 10−2 S/cm, but its scavenger effect reduces the number of radicals generated by irradiation, lessening the strain hardening effect. The employed mixing method provides a dispersion of MWCNTs in a PP matrix, which followed by an ad hoc irradiation, allows obtaining an electrical conductive polypropylene with a strain hardening behaviour. The obtained results open novel routes to conductive nanocomposites apt to be processed using methods discarded for linear PPs, such extrusion-blowing and others.