CNT aggregation mechanisms probed by electrical and dielectric measurements

Aggregation of carbon nanotubes in silicone oil was studied by electrical and dielectric measurements. The use of a liquid medium allowed us to slowly dilute and precisely vary the filler contents. With this method, the percolation thresholds were measured with a great accuracy. The filler aggregation process was also probed as a function of time, showing a decrease in the percolation threshold over time after agitation was stopped. In contrast with previous studies on dynamic percolation, in a liquid medium a progressive separation between fillers and matrices is evidenced at a long time. In addition, no permittivity divergence was measured at the transition, this also results from the liquid nature of the matrix.