2022 Volume 63 Issue 9 Pages 1281-1286
The effects of binder chemistry on electrical-conductivity development, i.e., dynamic percolation, in carbon nanotube (CNT)-filled epoxy-based pastes during curing were investigated. The electrical resistivities of the pastes are influenced not only by the dispersivity of the CNT filler but also by the binder chemistry of the pastes. The electrical-conductivity-development kinetics are accelerated by introducing a reactive diluent, namely phenyl glycidyl ether, to the binder. As shown by alternating current impedance spectroscopy, the electrical-conductivity development is governed by the decrease in interfacial electrical resistance between the filler units. Electrical-conductivity development does not occur synchronously with the curing shrinkage of the binder; thus, the chemical state of the interface adjacent to the fillers is a key parameter for enhancing electrical conductivity. Thus, control of this interfacial chemistry is an essential concept for developing electrically conductive CNT-filled pastes.
