Surface stress decomposition in large amplitude oscillatory interfacial dilatation of complex interfaces

Anteun de Groot; Jack Yang; Leonard M C Sagis

doi:10.1016/j.jcis.2023.02.007

Surface stress decomposition in large amplitude oscillatory interfacial dilatation of complex interfaces

J Colloid Interface Sci. 2023 May 15:638:569-581. doi: 10.1016/j.jcis.2023.02.007. Epub 2023 Feb 4.

Authors

Anteun de Groot¹, Jack Yang², Leonard M C Sagis³

Affiliations

¹ Laboratory of Physics and Physical Chemistry of Foods, Wageningen University, Bornse Weilanden 9, 6708WG Wageningen, The Netherlands.
² Laboratory of Physics and Physical Chemistry of Foods, Wageningen University, Bornse Weilanden 9, 6708WG Wageningen, The Netherlands; Laboratory of Biobased Chemistry and Technology, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands.
³ Laboratory of Physics and Physical Chemistry of Foods, Wageningen University, Bornse Weilanden 9, 6708WG Wageningen, The Netherlands. Electronic address: leonard.sagis@wur.nl.

PMID: 36773519
DOI: 10.1016/j.jcis.2023.02.007

Abstract

Hypothesis: Multiphase materials are often subjected to large deformations during processing, but the rheological responses of complex interfaces (e.g. stabilized by proteins) in this nonlinear deformation regime are still poorly understood. We expect nonlinearities in the response to be introduce by changes of the interfacial network and surface density of the emulsifier.

Experiments: Large amplitude oscillatory dilatation (LAOD) experiments were performed on WPI-, pea albumin-, pea globulin- and rapeseed lecithin-stabilized interfaces and analyzed with a general stress decomposition (GSD). With GSD, the stress response was decomposed into the four stress terms (τ₁-τ₄). Here, τ₁ and τ₂ represent, the elastic and viscous contribution of the odd Fourier harmonics, and τ₃ and τ₄ represent the dissipative and recoverable contribution of the even harmonics.

Findings: Analysis of WPI-, pea albumin-, pea globulin- and rapeseed lecithin-stabilized interfaces revealed that higher odd harmonics (k≥3) describe in-plane network responses and that even harmonics describe surface density changes. Analysis of these complex interfaces showed that GSD is a valuable tool for (quantitative) description of interfacial responses in LAOD, providing new insights into the origin of asymmetric nonlinear stress responses.

Keywords: Complex interfaces; Interfacial rheology; Large amplitude oscillatory dilatation; Lissajous plots; Multiphase materials; Stress decomposition.