Molecular Dynamics Simulation for Analysis of Surface Morphology of Tri-functional Lubricant Films

Coarse-grained molecular dynamics simulations have been applied to study the effect of polymer functionality on surface morphology of lubricant films. An effective molecular-mesh scanning method was newly introduced to detect the location of film surface. For comparisons, two kinds of double-functional perfluoropolyether (PFPE) Zdol 2000 and Zdol 4000 whose molecular weight was double that of Zdol 2000, and one tri-functional PFPE whose molecular weight was nearly the same as that of Zdol 4000 were selected. We clarified that the film surface of the tri-functional lubricant was smoother than Zdol 2000 when compared at the same film thickness condition