Surface rheology

Surface rheology is a description of the rheological properties of a free surface. When perfectly pure, the interface between fluids usually displays only surface tension.^[1] The stress within a fluid interface can be affected by the adsorption of surfactants in several ways:

Change in the surface concentration of surfactants when the in-plane flow tends to alter the surface area of the interface (Gibbs' elasticity).^[2]
Adsorption/desorption of the surfactants to/from the interface.^[3]

^ Lee, Junghaeng; Kim, Taehoon; Jang, Hyunkyu; Kwon, Mikyung; Cho, Kwang Soo (2023-02-01). "Rheological models for fluid mixtures: Theoretical foundation and linear viscoelasticity". Journal of Non-Newtonian Fluid Mechanics. 312: 104972. doi:10.1016/j.jnnfm.2022.104972. ISSN 0377-0257.
^ Langevin, Dominique (2020), "Thin Liquid Films", Emulsions, Microemulsions and Foams, Cham: Springer International Publishing, pp. 71–127, doi:10.1007/978-3-030-55681-5_2, ISBN 978-3-030-55680-8, retrieved 2023-11-28
^ Bergfreund, Jotam; Siegenthaler, Sarina; Lutz-Bueno, Viviane; Bertsch, Pascal; Fischer, Peter (2021-06-08). "Surfactant Adsorption to Different Fluid Interfaces". Langmuir. 37 (22): 6722–6727. doi:10.1021/acs.langmuir.1c00668. hdl:20.500.11850/490814. ISSN 0743-7463.