ո鴡: Polymer nanocomposites have unique multifunctional properties resulting from the size and shape of the fillers and display superior electrical, thermal and mechanical properties toconventional polymer composites due to the nanoscale size of the filler. Multiwall carbon nanotubes (MWCNT) as well as Copper and Silver nanowires were melt-mixedwithpolymers via solution mixing and in miniaturemixers, and electrical and mechanical properties were tested. The electrical,mechanical and rheological properties of these new materials were studied andevaluated for industrial applications such as personal electronics enclosures,shielding for aerospace, batteries and anti-static packaging. The morphology of thepolymer nanocomposites was characterized by transmission electron microscopy(TEM) and scanning electron microscopy (SEM) and revealed a unique honeycombstructure (segregated network structure) that helped to significantly lower theelectrical percolation threshold and increase electromagnetic shieldingproperties for applications such as cell phone and laptop enclosures. Hybridfiller systemsof Cu nanowire and carbon nanotubes in PS indicated that thereis an optimum nanofiller ratio for best electrical properties.Hybrid nanocomposites or MWCNT and Copper Nanowires (CuNW) displayed extremely lowelectrical percolation thresholds lower than 0.0005 volume fraction.The EMIshielding for these hybridmetal nanowire-polymer composites is among thehighest reported for nanocomposites. The outstanding performance of thesematerials in X-band also opens upopportunities for security and militaryapplications.By controlling the surface electrical properties of the filler, we found that there is an excellent opportunity to use these materials for charge storage applications by tuning the permittivity and dissipation factor.
Thursday, March 12, 2015 3:30 pm
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3:30 pm
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