On the Existence of Prewetting in Supracritical Fluid Mixtures

Jan Forsman; Clifford E. Woodward

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arXiv · 2410.19534

On the Existence of Prewetting in Supracritical Fluid Mixtures

Jan Forsman·Clifford E. Woodward

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Abstract

In this communication we demonstrate the existence of a first-order prewetting transition of a supracritical model polymer solution adjacent to an attractive surface. The model fluid we use mimics (qualitatively) an aqueous polyethylene oxide solution and, like the actual solution, displays a closed loop 2-phase region with an upper and lower critical solution temperature. The model fluid is shown to undergo a prewetting transition at an adjacent attractive surface even at temperatures below the lower critical solution temperature (supracriticality). This phenomenon follows from non-local thermodynamics when the lengthscale of the relevant fluid structures of surface films are commensurate or smaller than the range of intermolecular interactions.

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Jan Forsman, Clifford E. Woodward. 2024-10-25. On the Existence of Prewetting in Supracritical Fluid Mixtures. https://arxiv.org/abs/2410.19534

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