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Updated: Sep 19, 2025
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Preparation and High-temperature Anti-adhesion Behavior of a Slippery Surface on Stainless Steel
Published on: March 29, 2018
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Surfaces Slippery to Liquids: Wettability, Adhesion, and Contact Line Friction
Glen McHale1, Gary G Wells1, Rodrigo Ledesma-Aguilar1
1Institute for Multiscale Thermofluids, School of Engineering, The University of Edinburgh, Edinburgh EH9 3FB, U.K.
Langmuir : the ACS Journal of Surfaces and Colloids
|June 3, 2025
Summary
New research explores contact line friction for designing advanced surfaces that repel water and prevent icing. This work re-evaluates surface wettability and offers insights into developing eco-friendly coatings without harmful chemicals.
Area of Science:
- Surface Science and Engineering
- Materials Chemistry
- Tribology
Background:
- Maintaining dry, clean, and fouling-resistant surfaces is a persistent engineering challenge.
- Traditional approaches like superhydrophobicity focused on surface wettability.
- Recent advancements involve minimizing surface heterogeneity with liquid-infused or liquid-like surfaces.
Purpose of the Study:
- To present a conceptual framework for understanding contact line friction.
- To derive design principles for developing practical, advanced surfaces.
- To explore new coating opportunities free from poly- and perfluoroalkyl substances (PFAS).
Main Methods:
- Analysis of contact line friction based on surface and liquid-film contact angles.
- Incorporation of contact angle hysteresis in friction prediction models.
- Re-evaluation of the established wettability spectrum concept.
Main Results:
- Established a predictive model for contact line friction using contact angles and hysteresis.
- Demonstrated how these parameters guide the design of functional surfaces.
- Highlighted the limitations of solely focusing on wettability.
Conclusions:
- Contact line friction offers a new paradigm for surface design beyond traditional wettability.
- Understanding contact angles and hysteresis is key to friction control.
- Opens avenues for developing sustainable, PFAS-free coatings to combat 'Forever Chemicals'.
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