Electrical conductivity recovery in carbon nanotube polymer composites after transient shear

Investigations on electric conductivity have been performed on polycarbonate (PC) containing 0.6 vol% of multi-walled carbon nanotubes (MWNT) in a rheometer, where the plates act as capacitor plates for dielectric spectroscopy. The time dependent recovery of the DC-conductivity was recorded in the rest time after a transient shear deformation. The DC-conductivity shows a tremendous increase with the time after shearing. This conductivity recovery is explained by the reorganization of the conducting MWNT-network, which was destroyed by the shear. The reformation kinetics of MWNT-clusters is considered as a cooperative cluster-cluster aggregation coupled to electrical percolation of conductive MWNT. (c) 2007 WILEY-NCH Verlag GmbH & Co. KGaA, Weinheim.