Experimental and theoretical investigations of the rheological and electrical behavior of nanocomposites with universal percolation networks

摘要

Electrically conductive ceramic/polymer nanocomposites with universal percolation networks and varying contents of conductive nanoparticles were prepared herein; the effects of the dispersed state of the conductive nanoparticles on the electrical conductivity of the nanocomposites were investigated. The conductive nanocomposites were prepared by coating carbon black (CB) nanoparticles with a silane coupling agent, followed by their subsequent dispersion in the 1,6-hexanediol diacrylate (HDDA) photocurable polymer. The physical properties of the conductive nanocomposites, such as viscosity, photocurability, flowability, dispersibility, and electrical conductivity were investigated with respect to the loaded CB content. A correlation between conductivity and internal dispersibility was established by conducting theoretical analysis based on conditions of particle dispersion, aspect ratio, orientation, and interface. A comparison of the experimental values and theoretically obtained results assisted in identifying the nanoparticle network structure in the polymer matrix as universal percolation networks with imperfect/tunneling interfaces and a percolation threshold (c*) of 0.016. The electrical conductivity, heat deflection temperature (HDT), and tensile strength of 3D-printed conductive nanocomposite products were analyzed; scanning electron microscopy (SEM) was also employed to examine these samples. This study suggests a new development strategy for improving the quality of nano-products based on the quantitative dispersibility analysis of nanocomposite materials.