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A systematic electrical and rheological characterization of percolation in commercial polydisperse polystyrene (PS) nanocomposites containing multiwall carbon nanotubes (MWCNTs) is presented. The MWCNTs confer appreciable electrical conductivities (up to ca. 1 S/m) to these nanocomposites at a concentration of 8 vol %. In addition to enhancing the electrical properties, even at small concentrations (ca. 2 vol %), MWCNTs significantly enhance the rheological properties of PS melts. At concentrations exceeding 2 vol %, a plateau appears in the storage modulus G‘ at low frequencies, indicating the formation of a percolated MWCNT network that responds elastically over long timescales. Network formation, in turn, implies a diverging complex viscosity vs complex modulus curve. A focus of this study is on the correlation between electrical and rheological properties at the onset of percolation. The experimental results indicate that the elastic load transfer and electrical conductivity are far more sensitive to ...

Polyaromatic compounds, with terminal functional groups, can be non-covalently bonded to the sidewall of carbon nanotubes. This architecture preserves the structural, mechanical, electrical, and electromechanical properties of the CNTs and ensures that an unhindered functional group is available to bond with an extended polymer matrix. Spectroscopic measurements and high resolution imaging are used to confirm the functionalization and incorporation of functionalized MWNTs into a nylon 12 matrix.