▎ 摘　　要

The very low percolation thresholds in carbon nanotube and graphene polymer composites are of great recent interest. The values of these thresholds are basically determined by the extreme aspect ratios of the carbon particles. However, examining the many data in the literature we found that, surprisingly, for the corresponding composites the exclusion of the particles positions, due to their "hard cores," is very small. We propose that this is associated primarily with the bending of these carbon particles within the actual composites. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4752714]