Dear Colleagues, it is well known that contact angle hysteresis (the difference between the advancing and receding contact angles) is influenced both by surface roughness and by the non-homogeneous distribution of polar grops (or microenvironments) on the surface. It is also well known, that using various wetting liquids (most frequently diiodo-methane and water) it is possible to at least estimate the polar and dispersive parts of the surface energy of a given solid (there are more sophisticated distinctions as well). I looked for, but did not find relavant literature on the relation between the contact angle hysteresis and the polar/dispersive parts of the surface energy? To put it simply: if the polar part is higher, does it result in higher hysteresis? (In this question I consciously neglected the surface roughness problem, which is a pet topic of suprhydrophobicity, but I believe that other practical problems would benefit greatly if such a correlation could be found). I would appreciate comments, or relevant references.
Dear Gyorgy Banhegyi, the conventional treatment of this consider three components equation : state of the substrate (roughness/defects), viscosity (concentration) of the liquid, and line tension (interface). In this later component intermolecular forces may interfere. However, they are not considered seaparately. Usually, when polar forces exist, they dominate dispersive forces. My Regards
(Chapter 3 from the Book: Wetting of real surfaces, Bormashenko, Edward Yu 2013):
https://doi.org/10.1515/9783110258790.50
https://www.nature.com/articles/s42005-021-00691-4
https://doi.org/10.1039/C6SM00920D
https://doi.org/10.1021/acs.langmuir.0c02668
Gyorgy Banhegyi
You are looking to find the relationship between the contact angle hysteresis and the polar / dispersive components of the surface energy for practical use. It is rather difficult to find a connection. Perhaps this will help you.
1 the processes of inflow and outflow are different processes. The difference between the contact angles for the inflow and outflow is called the ordinal hysteresis. The term "ordinal" emphasizes the importance of the sequence of contact of the solid surface with the other two phases involved in wetting.
2.Although the polar surface energy differs from the dispersive one. It is difficult to separate them. There may be synergistic effects.
(3) For water, a contribution from the nuclear quantum effect may appear.
On your question, I recommend an article by a well-known specialist in wetting B. D. SUMM
http://www.pereplet.ru/obrazovanie/stsoros/811.html
In the second link, a more complex work on hydrophobic interactions between hydrophobic beads involving the nuclear quantum effect
Article Nuclear Quantum Effects in Hydrophobic Nanoconfinement
@ Yuri Mirgorod thank you very much for your answer. It was just a feeling on my side and I am glad to hear an expert opinion. Lately, I have read a lot of papers, but still feel a bit uneasy. The directly available data are the sessile drop contact angle, the advancing and receding angles. (All complicated by the problems of contact angle relaxation). The specific surface energy is not measurable directly, only by extrapolations, based on certain models. As far as I know, there is no well-established relation between the sessile drop Young angle, the advancing and receding angles. In most cases where I have experimental data, the cos(Young angle) cannot be obtained from the arithmetic average of the cosines of the advancing and receding angles.
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