Synergetic enhancement of thermal conductivity for highly explosive‐filled polymer composites through hybrid carbon nanomaterials

The one‐dimensional (1D) carbon nanotubes (CNTs) and two‐dimensional (2D) graphene nanoplatelets (GNPs) were adopted to enhance the thermal conductivity (K) of polymer‐bonded explosives (PBX). Seven 1,3,5‐triamino‐2,4,6‐trinitrobenzene (TATB)‐based PBX formulations without or with 1.31 vf % carbon materials were designed and fabricated. The results indicated that, the K was only slightly improved by pure GNPs or CNTs. However, a remarkable synergetic effect between GNPs and CNTs in improving the K of PBX was demonstrated. The K of PBX with hybrid GNPs and CNTs was obviously higher than that of PBX with pure GNPs or CNTs. The bridging interactions between GNPs and CNTs could lead to the formation of a more efficient 3D percolating network. Moreover, the presence of CNTs triggered the percolation effect in the GNPs as the enhanced K was more pronounced with increasing GNPs. Additionally, the nonlinear dependence of the K of PBX on GNPs content was fitted by an analytical model which incorporated the percolation effect. The theoretical results were found to be in reasonably good agreement with the experimental data. Finally, the thermal shock resistance of PBX with hybrid CNT/GNP was significantly enhanced. POLYM. COMPOS., 39:E1452–E1462, 2018. © 2017 Society of Plastics Engineers