Numerical analysis of Pickering emulsion stability: insights from ABMD simulations

Autor: Sicard, François, Striolo, Alberto
Rok vydání: 2016
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1039/C6FD00055J
Popis: The issue of the stability of Pickering emulsions is tackled at a mesoscopic level using dissipative particle dynamics simulations within the Adiabatic Biased Molecular Dynamics framework. We consider the early stage of the coalescence process between two spherical water droplets in decane solvent. The droplets are stabilized by Janus nanoparticles of different shapes (spherical and ellipsoidal) with different three-phase contact angles. Given a sufficiently dense layer of particles on the droplets, we show that the stabilization mechanism strongly depends on the collision speed. This is consistent with a coalescence mechanism governed by the rheology of the interfacial region. When the system is forced to coalesce sufficiently slowly, we investigate at a mesoscopic level how the ability of the nanoparticles to stabilize Pickering emulsions is discriminated by nanoparticle mobility and the associated caging effect. These properties are both related to the interparticle interaction and the hydrodynamic resistance in the liquid film between the approaching interfaces.
Comment: 15 pages (12 pages and Supplemental Information), 11 figures, to be published in Faraday Discussions (Royal Society of Chemistry)
Databáze: arXiv