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Electrically Conductive Metal Nanowire Polymer Nanocomposites

  • Author / Creator
    Luo, Xiaoxiong
  • This thesis investigates electrically conductive polymer nanocomposites formulated with metal nanowires for electrostatic discharge and electromagnetic interference shielding. Copper nanowires (CuNWs) of an average length of 1.98 µm and diameter of 25 ± 4 nm were synthesized. The oxidation reaction of the CuNWs in air can be divided into two stages at weight of 111.2% on TGA curves. The isoconversional activation energies determined by Starink method were used to fit the different master plots. Johnson-Mehl-Avrami (JMA) equation gave the best fit. The surface atoms of the CuNWs are the sites for the random nucleation and the crystallite strain in the CuNWs is the driving force for the growth of nuclei mechanism during the oxidation process. To improve the anti-oxidation properties of the CuNWs, silver was coated onto the surface of the CuNWs in Ag-amine solution. The prepared silver coated CuNWs (AgCuNWs) with silver content of 66.52 wt. %, diameter of 28–33 nm exhibited improved anti-oxidation behavior. The electrical resistivity of the AgCuNW/low density polyethylene (LDPE) nanocomposites is lower than that of the CuNW/LDPE nanocomposites with the same volume percentage of fillers. The nanocomposites formulated with CuNWs and polyethylenes (PEs) were compared to study the different interaction between the CuNWs and the different types of PE matrices. The electrical conductivity of the different PE matrices filled with the same concentrations of CuNWs correlated well with the level of the CuNW dispersion. The intermolecular force and entanglement resulting from the different macromolecular structures such as molecular weight and branching played an important role in the dispersion, electrical properties and rheological behaviour of the CuNW/PE nanocomposites. Ferromagnetic polycrystalline nickel nanowires (NiNWs) were synthesized with uniform diameter of ca. 38 nm and an average length of 2.68 µm. The NiNW linear low density polyethylene (LLDPE) nanocomposites exhibited electrical percolation threshold at NiNW volume fraction of 0.005. The power law fitting results imply that the electrical conductivity of the NiNW/LLDPE nanocomposites mainly originated from the contact among individual nanowires.

  • Subjects / Keywords
  • Graduation date
    2013-06
  • Type of Item
    Thesis
  • Degree
    Doctor of Philosophy
  • DOI
    https://doi.org/10.7939/R3W032
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.
  • Language
    English
  • Institution
    University of Alberta
  • Degree level
    Doctoral
  • Department
    • Department of Chemical and Materials Engineering
  • Specialization
    • Chemical Engineering
  • Supervisor / co-supervisor and their department(s)
    • Uttandaraman Sundararaj, Chemical and Petroleum Engineering, University of Calgary
    • Jingli Luo, Chemical and Materials Engineering, University of Alberta
  • Examining committee members and their departments
    • Dongyang Li, Chemical and Materials Engineering, University of Alberta
    • Yuning Li, Department of Chemical Engineering and Waterloo Institute for Nanotechnology (WIN), University of Waterloo
    • Jingli Luo, Chemical and Materials Engineering, University of Alberta
    • Uttandaraman Sundararaj, Chemical and Petroleum Engineering, University of Calgary
    • Jeffrey M. Stryker, Department of Chemistry, University of Alberta