Lubricant additive

Abstract

A lubricant formulation. The lubricant formulation includes a polyol-based base lubricant, an ionic liquid, and an organic nanoparticle. The ionic liquid is selected from the group consisting of trihexyltetradecylphosphonium bis(2-ethylhexyl) phosphate, trihexyl(tetradecyl)phosphonium bis-2,4,4-(trimethylpentyl)phosphinate, and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, or a combination thereof. The organic nanoparticle has a median particle size less than about 200 nm. The organic nanoparticle forms about 0.01 to about 5% by weight of the lubricant formulation. The ionic liquid forms about 0.5 to about 10% by weight of the lubricant formulation.

What is claimed is: 
     
         1 . A method of lubricating at least two metallic tribo-contact surfaces, the method comprising the steps of:
 applying a base lubricant between the metallic tribo-contact surfaces; and   after applying the base lubricant between the metallic tribo-contact surfaces, adding an additive to the base lubricant, the additive comprising organic nanoparticles dispersed in an ionic liquid.   
     
     
         2 . The method of  claim 1 , wherein the ionic liquid is halogen-free. 
     
     
         3 . The method of  claim 2 , wherein the ionic liquid is a phosphonium-based ionic liquid. 
     
     
         4 . The method of  claim 3 , wherein the ionic liquid is selected from the group consisting of trihexyltetradecylphosphonium bis(2-ethylhexyl) phosphate, trihexyl(tetradecyl)phosphonium bis-2,4,4-(trimethylpentyl)phosphinate, and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, and combinations thereof. 
     
     
         5 . The method of  claim 1 , wherein the organic nanoparticle is graphene or other submicron particle of carbon. 
     
     
         6 . The method of  claim 1 , wherein the organic nanoparticle has a median particle size less than about 200 nm. 
     
     
         7 . The method of  claim 3 , wherein the base lubricant is a polyol-based lubricant. 
     
     
         8 . A method of lubricating an aircraft to extend the duration of safe flight during a loss of lubrication event, the method comprising the steps of:
 adding organic nanoparticles dispersed in an ionic liquid to an aircraft lubrication system.   
     
     
         9 . The method of  claim 8 , wherein the organic nanoparticles and the ionic liquid are added to the aircraft lubrication system as a base lubricant additive. 
     
     
         10 . The method of  claim 8 , wherein the ionic liquid is halogen-free. 
     
     
         11 . The method of  claim 8 , wherein the ionic liquid is a phosphonium-based ionic liquid. 
     
     
         12 . The method of  claim 8 , wherein the organic nanoparticle is graphene or other submicron particle of carbon. 
     
     
         13 . A lubrication system comprising:
 a first metallic surface;   a second metallic surface; and   a protective tribocoating formed between the first and second metallic surfaces, the protective tribocoating comprising a polyol-based lubricant, an ionic liquid, and organic nanoparticles.   
     
     
         14 . The lubrication system of  claim 13 , wherein the ionic liquid is halogen-free. 
     
     
         15 . The lubrication system of  claim 13 , wherein ionic liquid is a phosphonium-based ionic liquid. 
     
     
         16 . The lubrication system of  claim 13 , wherein the organic nanoparticle is graphene or other submicron particle of carbon.