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arXiv · 1409.8646

Micelle fragmentation and wetting in confined flow

Mona Habibi·Colin Denniston·Mikko Karttunen
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Abstract

We use coarse-grained molecular-dynamics (MD) simulations to investigate the structural and dynamical properties of micelles under non-equilibrium Poiseuille flow in a nano-confined geometry. The effects of flow, confinement, and the wetting properties of die-channel walls on spherical sodium dodecyl sulfate (SDS) micelles are explored when the micelle is forced through a die-channel slightly smaller than its equilibrium size. Inside the channel, the micelle may fragment into smaller micelles. In addition to the flow rate, the wettability of the channel surfaces dictates whether the micelle fragments and determines the size of the daughter micelles: The overall behavior is determined by the subtle balance between hydrodynamic forces, micelle-wall interactions and self-assembly forces.

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Mona Habibi, Colin Denniston, Mikko Karttunen. 2014-09-30. Micelle fragmentation and wetting in confined flow. https://doi.org/10.1209/0295-5075%2F108%2F28005

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