Contact Line Pinning on Microstructured Surfaces for Liquids in the Wenzel State
2010 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 26, no 2, 860-865 p.Article in journal (Refereed) Published
The wettability of surfaces microstructured with square pillars was studied, where the static advancing contact angle on the planar surface was 72 degrees. We observed elevated advancing angles (up to 140 degrees) on these structures for droplets in the Wenzel state. No air was trapped in the structured surf ices beneath the liquid, ruling out the well-known Lotus leaf effect. Instead, we show that the apparent hydrophobicity is related to contact line pinning at the pillar edges, giving a strong dependence of wetting hysteresis oil the fraction of the contact line pinned on pillars. Simulating the contact line pinning oil these Surfaces showed similar behavior to our measurements, revealing both strong pinning at the edges of the pillars as well as mechanistic details.
Place, publisher, year, edition, pages
2010. Vol. 26, no 2, 860-865 p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-141028DOI: 10.1021/la902296dISI: 000273403400034OAI: oai:DiVA.org:uu-141028DiVA: diva2:384830