Fragility of Polymer Nanocomposites with Ideal Nanoparticle Dispersion

ORAL

Abstract

We investigate the impact of the addition of nanoparticles (NP) on the fragility of a model glass forming polymer melt by molecular dynamics simulation. We first consider a fixed density path and find that the fragility changes, like the change in the glass transition temperature, follow directly from the attractive or repulsive polymer-NP interactions. We further show how the fragility can be connected with local vibrational changes, quantified by the Debye-Waller factor. We contrast these results with those we obtain along a path of fixed pressure, more experimentally relevant. For the isobaric case, we find changes in packing can have a larger effect on fragility than surface effects due only to NP interactions at fixed system density.

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Authors

  • Beatriz Pazmino

    • Physics Dept., Wesleyan University, Middletown, CT

  • Jack Douglas

    • National Institute of Standards and Technology
    • Polymers Division, NIST Gaithersburg
    • National Institute of Standards and Technology, Gaithersburg, MD, USA
    • Polymer Division, NIST, Gaithersburg, MD
    • Polymers Division, NIST
    • Polymers Division, National Institute of Standards and Technology, Gaithersburg, MD 20899
    • NIST
    • Polymers Division, NIST, USA

  • Francis Starr

    • Physics Dept., Wesleyan University, Middletown, CT
    • Wesleyan University
    • Physics Dept., Wesleyan University, Middletown
    • Physics Dept, Wesleyan University, Middletown CT
    • Wesleyan U., Middletown, CT