Enhancement of Electrical and Thermomechanical Properties of Silver Nanowire Composites by the Introduction of Nonconductive Nanoparticles: Experiment and Simulation

Abstract

Electrically conductive polymer nanocomposites have been applied extensively in many fields to develop the next generation of devices. Large amounts of conductive nanofillers in polymer matrices are, however, often required for a sufficiently high electrical conductivity, which in turn deteriorates the desired thermomechanical properties. We illustrate a novel but facile strategy to improve the electrical conductivity and the thermomechanical property of silver nanowire/polymer nanocomposites. We find that one may increase the electrical conductivity of silver nanowire/polymer nanocomposites by up to about 8 orders of magnitude by introducing silica nanoparticles with nanocomposites. The electrical percolation threshold volume fraction of silver nanowires decreases from 0.12 to 0.02. Thermomechanical properties also improve as silica nanoparticles are introduced. We carry out extensive Monte Carlo simulations to elucidate the effects of silica nanoparticles at a molecular level and find that van der Waals attractive interaction between silica nanoparticles and silver nanowires dominates over the depletion-induced interaction between silver nanowires, thus improving the dispersion of silver nanowires. Without silica nanoparticles, silver nanowires tend to aggregate, which is why additional silver nanowires are required for a desired electrical conductivity. On the other hand, with silica nanoparticles mixed, the electrical percolating network is likely to form at a smaller volume fraction of silver nanowires.

Outstanding electromagnetic interference shielding of silver nanowires: comparison with carbon nanotubes

“…Regarding the choice of llers, MWCNTs are proposed as promising candidates due to their huge surface area, high electrical conductivity, signicant corrosion resistance and industrial growth. 28,29 Accordingly, the literature comprises several studies that employed AgNWs as conductive nanollers in CPCs with the focus on electrical conductivity, [30][31][32][33] or EMI shielding behavior. These properties commend MWCNTs as excellent llers for EMI shielding applications.…”

Enhancement of electrostatic charge dissipation properties of polymers by a sustained-release effect of mesoporous silica nanoparticles

“…The incorporation of MCM‐41 to the SMS/PS composites also improves thermal properties through decreasing the CTE and increasing the decomposition temperature. Recent studies showed that conductive nanocomposites with a large CTE can cause reliability problems for electrical interconnections, because the mismatch of CTE between nanocomposites and substrates can lead to cracking and delamination at the interface during repeated thermal cycling, thus resulting in the mechanical and functional failure . As shown in Fig.…”

“…To achieve high electrical conductivity, a large amount of the additives in a polymer matrix is usually required (above 5 wt%) . This may deteriorate other physical properties of composites, such as optical transparency, mechanical properties, and viscosity, thus limiting the application of these polymer composites.…”

High-performance epoxy/silica coated silver nanowire composites as underfill material for electronic packaging

“…3b-d, AgNWs tend to agglomerate and are poorly dispersed in epoxy with high loading. This may be due to the unfavorable interactions between hydrophilic AgNWs and hydrophobic epoxy [34,35]. Also, the high surface energy of AgNWs does not favor well-dispersed epoxy/AgNWs composites.…”