The Impact of an Emergent Hierarchical Filler Network on Nanocomposite Dynamics

ORAL

Abstract

The performance of nanoscale-filled elastomers is related to the structure of the aggregated filler network in addition to interfacial chemical affinity and filler dispersion. This structure emerges due to a competition between the thermodynamically driven filler immiscibility and the kinetically driven mixing process. A hierarchical filler network model evidenced in x-ray scattering is linked to the dynamic response at low strains in the linear viscoelastic regime. The primary nanoscale network that percolates locally at ~5 vol % displays a mesh-size, which is related to the changes in the dynamic spectrum at frequencies below the Einstein-Smallwood enhancement associated with the elastomer within the network pores in the high frequency region. The secondary micron-scale network associated with the Payne effect and bulk electrical conductivity that percolates globally at ~20 vol %, influences the gel-like dynamic response at very low frequencies. The hierarchical filler network is described by two crossover frequencies in the dynamic spectrum and two related structural scaling regimes.

*Supported by the National Science Foundation through grants CMMI-1635865 and CMMI-1636036. This research used resources of the Advanced Photon Source under Contract No. DE-AC02-06CH11357.

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Presenters

  • Kabir Rishi

    • Dept. Chem. and Mat. Eng, University of Cincinnati, OH
    • Chemical and Materials Engineering, University of Cincinnati
    • University of Cincinnati

Authors

  • Kabir Rishi

    • Dept. Chem. and Mat. Eng, University of Cincinnati, OH
    • Chemical and Materials Engineering, University of Cincinnati
    • University of Cincinnati

  • Greg Beaucage

    • Dept. Chem. and Mat. Eng, University of Cincinnati, OH
    • Chemical and Materials Engineering, University of Cincinnati
    • University of Cincinnati

  • Vikram K Kuppa

    • University of Dayton Research Institute, University of Dayton, OH
    • Nonstructural Materials Division, University of Dayton Research Institute
    • University of Dayton Research Institute, Nonstructural Materials Division, University of Dayton
    • University of Dayton Research Institute

  • Alex McGlasson

    • Chemical and Materials Engineering, University of Cincinnati
    • University of Cincinnati

  • Jan Ilavsky

    • Advanced Photon Source, Argonne National Laboratory