Spreading of liquid mixtures at the microscopic scale: A molecular dynamics study of the surface-induced segregation process

The spreading of liquid mixtures on a solid substrate is studied using Mole cular Dynamics. The droplets are constituted by 16-atom and 8-atom chains a nd the solid substrate is described at the atomic level. In all the simulat ions reported here, the atoms are, for simplicity, equidistributed among th e two types of molecules (50%-50%). The influence of the strength of the so lid, short molecules interaction on the coating of the solid surface by the liquid first layer is analyzed, for both the "wetting/nonwetting" and "wet ting/ wetting" mixtures. A surface-induced segregation process of the mixtu re is reported in the "wetting/ nonwetting" case and the conditions accordi ng to which this segregation of the initial drop occurs are investigated.