Equilibrium structure and mechanical properties of bidisperse concentrated emulsions
Journal
Physics of Fluids
Journal Volume
37
Journal Issue
9
Start Page
093366
ISSN
10706631
Date Issued
2025-09-01
Author(s)
Abstract
Concentrated emulsions possessing a jammed structure exhibit distinct solid-like behaviors, with their properties significantly influenced by droplet size and polydispersity. As a first exploration of polydispersity, bidisperse concentrated emulsions with precisely controlled droplet sizes are studied using dissipative particle dynamics simulations. The effects of varying droplet size ratios and large droplet fractions (ϕL) on the microstructure, thermodynamic properties, and mechanical properties are examined. From the radial distribution functions, the spatial arrangement of droplets is similar to that in monodisperse emulsions, with no segregation of large or small droplets occurring. Considering the mean droplet radius ( R ¯ ) as the reciprocal mean, both interfacial internal energy and osmotic pressure are proportional to 1 / R ¯ , while the self-diffusion coefficient of the continuous phase increases as R ¯ increases. Each elastic modulus (bulk, shear, and Young's) rises linearly with either decreasing ϕL or increasing 1 / R ¯ , indicating that smaller characteristic droplet sizes and higher effective Laplace pressure lead to greater resistance to deformation. In addition, the linear mixing model and the modulus-size relation for determining the moduli are presented. The Poisson's ratio remains close to 0.5, confirming the incompressibility of the material.
SDGs
Publisher
American Institute of Physics
Type
journal article