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.

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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