Method for improving emulsion characteristics of engine oils

Abstract

A method for improving the ability of an engine lubricating oil contaminated with water and fuel to emulsify water contamination by using as the engine lubricating oil a formulated oil including a lubricating oil base stock as a major component and a coupled block copolymer as a minor component. A method for improving thermo-oxidative stability and elastomer compatibility in an engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil including a lubricating oil base stock as a major component and a coupled block copolymer as a minor component. A lubricating engine oil including a lubricating oil base stock as a major component and a coupled block copolymer as a minor component.

What is claimed is: 
     
         1 . A method selected from:
 (a) a method for improving the ability of an engine lubricating oil contaminated with water and fuel to emulsify water contamination by using as the engine lubricating oil a formulated oil comprising a lubricating oil base stock as a major component and a coupled block copolymer as a minor component;   
       wherein the coupled block copolymer comprises:
 an “A” block of a functionalized hydrocarbon moiety including one or more functional end groups derived from: epoxides, amines, acids, acid chlorides, acid anhydrides, halogens, vinyl or vinylidene double bonds, aromatic rings or thiols; and 
 a “B” block of a functionalized polyether moiety including one or more functional end groups derived from: epoxides, amines, acids, acid chlorides, acid anhydrides, halogens, vinyl or vinylidene double bonds, aromatic rings or thiols; 
 wherein the end group of the polyether moiety is different than the end group of the hydrocarbon moiety, and the hydrocarbon moiety and the polyether moiety are copolymerizable therewith; and 
 wherein, in an engine lubricated with said lubricating oil, the ability of the engine lubricating oil contaminated with water and fuel to emulsify water contamination is improved as compared to the ability of an engine lubricating oil contaminated with water and fuel to emulsify water contamination using a lubricating oil containing a minor component other than the coupled block copolymer; and 
 (b) a method for improving thermo-oxidative stability and elastomer compatibility in an engine lubricated with a lubricating oil by using as the lubricating oil a formulated oil comprising a lubricating oil base stock as a major component and a coupled block copolymer as a minor component; wherein the coupled block copolymer comprises: 
 an “A” block of a functionalized hydrocarbon moiety including one or more functional end groups derived from: epoxides, amines, acids, acid chlorides, acid anhydrides, halogens, vinyl or vinylidene double bonds, aromatic rings or thiols; and 
 a “B” block of a functionalized polyether moiety including one or more functional end groups derived from: epoxides, amines, acids, acid chlorides, acid anhydrides, halogens, vinyl or vinylidene double bonds, aromatic rings or thiols; 
 wherein the end group of the polyether moiety is different than the end group of the hydrocarbon moiety, and the hydrocarbon moiety and the polyether moiety are copolymerizable therewith; and 
 wherein, in an engine lubricated with said lubricating oil, thermo-oxidative stability and elastomer compatibility are improved as compared to thermo-oxidative stability and elastomer compatibility achieved using a lubricating oil containing a minor component other than the coupled block copolymer. 
 
     
     
         2 . The method of  claim 1  wherein the lubricating oil base stock comprises a Group I, II, III, IV or V base oil stock. 
     
     
         3 . The method of  claim 1  wherein the lubricating oil base stock comprises a poly alpha olefin (PAO) base stock. 
     
     
         4 . The method of  claim 1  wherein the hydrocarbon moiety is a poly-α-olefin and the polyether moiety is a polyalkylene glycol, and wherein the poly-α-olefin is difunctional and the polyalkylene glycol is difunctional. 
     
     
         5 . The method of  claim 4  wherein the polyalkylene glycol is a Jeffamine® polyetheramine, and wherein the Jeffamine® polyetheramine is at least one amine selected from the group consisting of: poly(propyleneglycol) bis(2-aminopropylether), and poly(propyleneglycol)-block-poly(ethyleneglycol-block poly(propyleneglycol) bis(2-aminopropylether). 
     
     
         6 . The method of  claim 1  wherein the hydrocarbon moiety is an alkyl glycidyl ether, Armeen® amine or dioctylamine. 
     
     
         7 . The method of  claim 1  wherein the block copolymer comprises a diblock copolymer or a repeating diblock copolymer, and wherein the block copolymer has an average molecular weight of 200 to 20000. 
     
     
         8 . The method of  claim 1  wherein the coupled block copolymer is present in an amount sufficient for the lubricating oil to pass ILSAC GF-5 specification and/or ASTM D7563, or wherein the ability of the engine lubricating oil to emulsify water and fuel as measured by ASTM D7563 shows no observable aqueous layer. 
     
     
         9 . The method of  claim 1  wherein the lubricating oil base stock is present in an amount of 50 to 90 wt % of the lubricant composition, and the coupled block copolymer is present in an amount of 1 to 10 wt % of the lubricant composition. 
     
     
         10 . The method of  claim 1  wherein the lubricating oil further comprises one or more of a viscosity improver, antioxidant, ashless antioxidant, antiwear, detergent, dispersant, pour point depressant, corrosion inhibitor, metal deactivator, seal compatibility additive, anti-foam agent, inhibitor, and anti-rust additive. 
     
     
         11 . A lubricating engine oil selected from:
 (a) a lubricating engine oil comprising a lubricating oil base stock as a major component and a coupled block copolymer as a minor component;   
       wherein the coupled block copolymer comprises:
 an “A” block of a functionalized hydrocarbon moiety including one or more functional end groups derived from: epoxides, amines, acids, acid chlorides, acid anhydrides, halogens, vinyl or vinylidene double bonds, aromatic rings or thiols; and 
 a “B” block of a functionalized polyether moiety including one or more functional end groups derived from: epoxides, amines, acids, acid chlorides, acid anhydrides, halogens, vinyl or vinylidene double bonds, aromatic rings or thiols; 
 wherein the end group of the polyether moiety is different than the end group of the hydrocarbon moiety, and wherein the hydrocarbon moiety and the polyether moiety are copolymerizable therewith; and 
 wherein, in an engine lubricated with said lubricating oil, the ability of the engine lubricating oil contaminated with water and fuel to emulsify water contamination is improved as compared to the ability of an engine lubricating oil contaminated with water and fuel to emulsify water contamination using a lubricating oil containing a minor component other than the coupled block copolymer; and 
 (b) a lubricating engine oil comprising a lubricating oil base stock as a major component and a coupled block copolymer as a minor component; 
 
       wherein the coupled block copolymer comprises:
 an “A” block of a functionalized hydrocarbon moiety including one or more functional end groups derived from: epoxides, amines, acids, acid chlorides, acid anhydrides, halogens, vinyl or vinylidene double bonds, aromatic rings or thiols; and 
 a “B” block of a functionalized polyether moiety including one or more functional end groups derived from: epoxides, amines, acids, acid chlorides, acid anhydrides, halogens, vinyl or vinylidene double bonds, aromatic rings or thiols; 
 wherein the end group of the polyether moiety is different than the end group of the hydrocarbon moiety, and wherein the hydrocarbon moiety and the polyether moiety are copolymerizable therewith; and 
 wherein, in an engine lubricated with said lubricating oil, thernmo-oxidative stability and elastomer compatibility are improved as compared to thermo-oxidative stability and elastomer compatibility achieved using a lubricating oil containing a minor component other than the coupled block copolymer. 
 
     
     
         12 . The lubricating engine oil of  claim 11  wherein the lubricating oil base stock comprises a Group I, II, III, IV or V base oil stock. 
     
     
         13 . The lubricating engine oil of  claim 11  wherein the lubricating oil base stock comprises a poly alpha olefin (PAO) base stock. 
     
     
         14 . The lubricating engine oil of  claim 11  wherein the hydrocarbon moiety is a poly-α-olefin and the polyether moiety is a polyalkylene glycol, and wherein the polyalkylene glycol is difunctional and the poly-α-olefin is difunctional. 
     
     
         15 . The lubricating engine oil of  claim 14  wherein the polyalkylene glycol is a Jeffamine® polyetheramine, and wherein the Jeffamine® polyetheramine is at least one amine selected from the group consisting of: poly(propyleneglycol) bis(2-aminopropylether), and poly(propyleneglycol)-block-poly(ethyleneglycol-block poly(propyleneglycol) bis(2-aminopropylether). 
     
     
         16 . The lubricating engine oil of  claim 11  wherein the hydrocarbon moiety is an alkyl glycidyl ether, Armeen® amine or dioctylamine. 
     
     
         17 . The lubricating engine oil of  claim 11  wherein the block copolymer comprises a diblock copolymer or a repeating diblock copolymer, and wherein the block copolymer has an average molecular weight of 200 to 20000. 
     
     
         18 . The lubricating engine oil of  claim 11  wherein the coupled block copolymer is present in an amount sufficient for the lubricating oil to pass ILSAC GF-5 specification and/or ASTM D7563, or wherein the ability of the engine lubricating oil to emulsify water and fuel as measured by ASTM D7563 shows no observable aqueous layer. 
     
     
         19 . The lubricating engine oil of  claim 11  wherein the lubricating oil base stock is present in an amount of 50 to 80 wt % of the lubricant composition, and the coupled block copolymer is present in an amount of 1 to 10 wt % of the lubricant composition. 
     
     
         20 . The lubricating engine oil of  claim 11  wherein the lubricating oil further comprises one or more of a viscosity improver, antioxidant, ashless antioxidant, antiwear, detergent, dispersant, pour point depressant, corrosion inhibitor, metal deactivator, seal compatibility additive, anti-foam agent, inhibitor, and anti-rust additive. 
     
     
         21 . The method of  claim 10  wherein the lubricating oil comprises a lubricating oil base stock selected from a Group I, II, III, IV or V base oil stock, a poly-α-olefin (PAO)-polyalkylene glycol (PAG) coupled block copolymer, a salicylate, sulfonate or phenate based detergent, an ashless antioxidant, a succinimide based dispersant, a zinc dialkyldithiophosphate (ZDDP), a friction modifier, a corrosion inhibitor, and a defoamant. 
     
     
         22 . The lubricating engine oil of  claim 20  which comprises a lubricating oil base stock selected from a Group I, II, III, IV or V base oil stock, a poly-α-olefin (PAO)-polyalkylene glycol (PAG) coupled block copolymer, a salicylate, sulfonate or phenate based detergent, an ashless antioxidant, a succinimide based dispersant, a zinc dialkyldithiophosphate (ZDDP), a friction modifier, a corrosion inhibitor, and a defoamant.