Influence of Hydrodynamic Interactions on Stratification in Drying Mixtures

ORAL

Abstract

It is desirable to control the structure of dried multicomponent films for many technologies, but there is an incomplete theoretical understanding of how evaporation affects film structure. Recent experiments1 showed that mixtures of small and large colloids unexpectedly stratify with the small colloids counterintuitively on top of the large colloids. Stratification can be modeled without hydrodynamic interactions (HIs) using dynamic density functional theory, but it was recently suggested2 that HIs cannot be reasonably neglected. We investigated the influence of HIs on stratification using nonequilibrium simulations of polymer films with explicit and implicit solvent models.3 The short chains stratified on top of the long chains in the implicit solvent (no HIs) in agreement with previous theoretical models and simulations. However, the explicit solvent model did not stratify at the same drying conditions due to HIs. Our work shows that it is critical to include HIs into models for drying films.

1. Fortini et al. Phys. Rev. Lett. 116, 118301 (2016)
2. Sear & Warren, Phys. Rev. E 96, 062602, (2017)
3. Statt et al. J. Chem. Phys. 149, 024902 (2018)

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Presenters

  • Antonia Statt

    Princeton University

Authors

  • Antonia Statt

    Princeton University

  • Michael P Howard

    Princeton University, McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, McKetta Department of Chemical Engineering, University of Texas at Austin, McKetta Department of Chemical Engineering, University of Texas, Austin

  • Athanassios Panagiotopoulos

    Chemical and Biological Engineering, Princeton University, Princeton University