Viscoelasticity, yield stress, and diffusivity in jammed monodisperse emulsions: effects of droplet size
Journal
Journal of Molecular Liquids
Journal Volume
435
Start Page
128112
ISSN
0167-7322
Date Issued
2025-10-01
Author(s)
Abstract
Concentrated emulsions exhibit solid-like behavior due to their jammed structure, and their properties are significantly influenced by droplet size. However, in experiments, limitations in accurately controlling droplet size hinder systematic investigations of its effects. To generate emulsions composed of precisely uniform droplets, this study employs dissipative particle dynamics simulations and explores how the droplet radius (d) affects the thermodynamic and rheological properties of monodisperse concentrated emulsions. At equilibrium, both interfacial internal energy and osmotic pressure are proportional to d−1. Diffusive behavior of the continuous phase resembles that in porous media, showing slower diffusion and increased tortuosity with decreasing d. Moreover, the shear-thinning viscosity and static yield stress determined from shear flow, as well as the dynamic yield stress and flow point obtained from oscillation tests, are all found to increase linearly with d−1. Due to higher Laplace pressure, smaller droplets are shown to resist deformation more and require greater stress to initiate shear or elongational flow.
Subjects
Concentrated emulsion
Diffusion
Osmotic pressure
Shear-thinning
Yield stress
Publisher
Elsevier BV
Type
journal article