Computational Chemistry of Soluble Additives for Perfluoropolyalkylether Liquid Lubricants

Computational chemistry has been applied in a practical manner to a perfluoropolyalkylether (PFPAE) liquid lubricant research and development program. Additives have been previously shown to be effective in a PFPAE liquid lubricant candidate gas turbine engine oil base fluid as oxidation inhibitors/metal deactivators, lubricity additives and antirust additives. In this effort, low energy configuration computer models of the base fluid and of selected additives were created. Simulated docking of the additive molecules in the base fluid media, onto low carbon steel and onto iron oxide substrates, provided information on the strength of the substrate/additive interactions. Also, the visual representation of each additive molecule's alignment on the metallic surface has provided insight into selection of the optimnum functionality in designing new additives. Data on the additive/metal attraction and corresponding additive effectiveness are presented.