Nanoparticulates at liquid/liquid interfaces

Abstract

We analyse using molecular dynamics simulation the wetting behaviour of a particulate of nanometer size at a liquid/liquid interface. Our study shows that Young's equation provides accurate predictions of the contact angles that the particulate makes with the interface. This is found to be the case even for very small particulates whose size (≈15 Å) is approximately the same as the width of the interface. The line tension is an approximately linear function of the surface tension of the liquid/liquid interface. For the larger particulates studied here the line tensions are positive and of the order 10^-11 N, similar to values obtained from experiment on colloidal particles in the water/air interface.

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