Oscillatory structural forces probed by the nanofilm Macroscopic contact angle

The research on oscillatory structural forces (OSF) has a long history. OSF arise when liquid dispersions of a nano/micellar solution of complex fluids are confined between surfaces. In recent years, significant pro-gress has been made in the measuring and modeling of OSF. Advanced techniques that use tools such as the surface forces apparatus (SFA), colloidal probe atomic force microscope (CP-AFM), and foam film cap-illary balance (FCB) were developed to gain information about nanofilm interactions in the confinement film geometry as the layer and in-layer particle entropy structural transition takes place. Henderson's theory, based on the statistical mechanics approach to model the OSF, proposed analytical results using the Laplace transformation of the radial distribution function (RDF) for two large hard spheres in a fluid to calculate the film free energy; this approach is commonly applied to the model of the nanofilm layering between two solid surfaces. To extend Henderson's theory to model the layer and in-layer structural transition of a capillary system, e.g., foam and emulsions, we propose the use of the foam film-meniscus macroscopic contact angle approach to calculate the nanofilm's OSF.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

The research discusses the history and recent advances in the measurement and modeling of oscillatory structural forces (OSF), including the use of advanced techniques and Henderson's theory. It also proposes a method to extend the theory to model the layer and in-layer structural transition of a capillary system.