Increasing the electrical conductivity of polymer nanocomposites under the external field by tuning nanofiller shape

Abstract

It is very important to improve the electrical conductivity of polymer nanocomposites (PNCs), which can be used under the external field. In this work, by employing a coarse-grained molecular dynamics simulation, the effect of the external fields (tensile field and shear field) on the conductive probability of PNCs has been investigated in details by tuning the nanofiller shape. By carefully analyzing the conductive network, compared with the rod filler and the sphere filler, the Y filler and the X filler can protect the conducive networks well from their breakage perpendicular to the external fields, which thus can significantly enhance the conductive probability under the external fields. In other words, compared with under the quiescent state, the decrease or the increase of the conductive probability under the external fields depends on the nanofiller shape. Meanwhile, it is interesting to find that both the directional conductive probabilities parallel to the shear field and perpendicular to the shear field increase with the shear rate for the Y fillers, which further reflects their high conductive probability under the shear field. The reason can be attributed to two aspects: (1) the gradual aggregation of Y fillers under the external field; (2) the multi-arm structures of Y fillers. In summary, this work presents some further understanding how to improve the electrical conductivity of PNCs under the external fields by tuning the nanofiller shape.