Dispersibility-tailored conductive epoxy nanocomposites with silica nanoparticle-embedded silver nanowires

Abstract

We prepared epoxy/silver nanowire (AgNW) nanocomposites with excellent dispersibility and electrical conductivity by optimally embedding silica nanoparticles (SNPs) on AgNW surface. Through the use of tailored SNP-embedded content, enhanced electrical properties, such as high electrical conductivity (~101 S/m) and low electrical percolation threshold (<0.5 wt%) of epoxy nanocomposites were realized due to superb dispersion. Interfacial interactions between the epoxy matrix and SNP-AgNWs were improved by the combination of physical attraction and chemical reactions between the matrix and silanol moieties of silica, which led to the uniform dispersion of the nanowires in the matrix. The nanocomposites with well-chosen surface modification (i.e., embedding SNPs (2 h-reaction) on AgNW surface) exhibited results (~101 S/m) superior to those with untreated (~10−1 S/m) and highly treated surfaces (24 h-reaction; ~10−2 S/m). Rheological and electrical properties of the nanocomposites were primarily probed based on dispersion of nanowires influenced by the SNP coating on AgNW. Moreover, the morphological, compositional, and thermal properties of the nanocomposites were examined.