1. Electrical and Rheological Percolation in Polystyrene/MWCNT Nanocomposites
- Author
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Bani H. Cipriano, Arun K. Kota, Srinivasa R. Raghavan, Alan L. Gershon, Hugh A. Bruck, Dan Powell, and Matthew K. Duesterberg
- Subjects
Materials science ,Nanocomposite ,Polymers and Plastics ,Rheometry ,Organic Chemistry ,Concentration effect ,Carbon nanotube ,Dynamic mechanical analysis ,law.invention ,Condensed Matter::Soft Condensed Matter ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Electrical resistivity and conductivity ,law ,Percolation ,Polymer chemistry ,Materials Chemistry ,Polystyrene ,Composite material - Abstract
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 Gā 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 ...
- Published
- 2007