6533b872fe1ef96bd12d3947

RESEARCH PRODUCT

Method for wettability characterization based on contact line pinning.

Kurt BinderA. MilchevA. MilchevD. I. Dimitrov

subject

Condensed Matter::Soft Condensed MatterPhysics::Fluid DynamicsContact angleWork (thermodynamics)Materials scienceInterface (computing)Contact lineThermodynamicsWettingMechanicsCurvatureNanoscopic scaleCharacterization (materials science)

description

We demonstrate an efficient and reliable method for wettability characterization by determining the contact angle theta which a liquid-vapor interface makes with a solid wall. The purpose is to overcome the difficulties, related to the curvature of the liquid-vapor interface, which make measurements of theta rather uncertain, especially on the micro- and nanoscale. The method employs a specially designed slitlike channel in contact with a reservoir whereby the wettability of one of the slit walls is to be examined whereas the other (auxiliary) wall is separated by half into a lyophilic and a lyophobic part so as to pin the incoming fluid and fix the one end of the liquid-vapor interface. In the present work, the physical background of the method is elucidated theoretically while the method's applicability is demonstrated by molecular-dynamics simulation of a typical Lennard-Jones fluid, in contact with an atomistic wall. The wettability of the latter, as described by the corresponding contact angle theta, is accurately determined by variation of the liquid-wall interaction in a very broad interval.

10.1103/physreve.81.041603https://pubmed.ncbi.nlm.nih.gov/20481731