Epoxidized ester additives for reducing lead corrosion in lubricants and fuels

Abstract

Fuels, especially hydrocarbon fuels, and lubricants, especially lubricating oils, contain a class of anti-corrosion, anti-fatigue, and anti-wear additives that are derived epoxidized esters of fatty acids. Epoxidized 2-ethylhexyl tallate is particularly effective.

1 . A composition comprising: 
 (A) a lubricant or a hydrocarbon fuel, and    (B) at least one epoxidized ester of the formula:                        wherein:    m is 1 to 36;    R 1  and R 2  are independently selected hydrocarbyl groups, optionally substituted with alkyl, cycloalkyl, alkenyl, aryl or alkoxy groups, and optionally containing OH, ether, or epoxide functionalities,    or R 1  is a polyol residue selected from the group consisting of                          wherein:      n is O to about 12;    R 4 , R 5 , and R 9  are independently selected from the group consisting of hydrogen and hydrocarbyl;    R 6  is selected from the group consisting of linear alkylene, branched alkylene, linear alkenyl, and branched alkenyl; and    R 3 , R 7 , and R 8  are independently selected from the group consisting of hydrogen and an acyl group of the form:                          wherein R 10  is hydrocarbyl, which may be further substituted.    
     
     
         2 . The composition of  claim 1  further comprising an additive that is corrosive to lead and/or copper.  
     
     
         3 . The composition of  claim 2  wherein the corrosive additive is selected from the group consisting of glycerol monooleate, partially hydrolyzed vegetable oils, full and partial esterification products of diols and polyols with and C 6 -C 36  carboxylic acids, C 6 -C 50  carboxylic acids, amides derived from C 6 -C 50  carboxylic acids, esters of hydroxypolycarboxylic acids, tetraalkyl thiuram disulfides, thionamides, thioureas, dithiocarbamates, hydrazides, succinylhydrazides, 4-imidazolidine thiones, 1,3,4-oxadiazole-2(3H)-thiones, 1,3,4-thiadiazolane-2-thiones, 2,3-dihydro-1,3,4-oxadiazoles, and mixed thio acid amide molybdenum complexes.  
     
     
         4 . The composition of  claim 1  wherein the epoxidized ester is an ester of a C 6 -C 22  unsaturated or polyunsaturated carboxylic acid or mixtures thereof.  
     
     
         5 . The composition of  claim 1  wherein the epoxidized ester is an ester of epoxidized oleic or linoleic acid, or a mixture thereof.  
     
     
         6 . The composition of  claim 1  wherein the epoxidized ester is an epoxidized C 4 -C 12  ester of oleic or linoleic acid, or mixture thereof.  
     
     
         7 . The composition of  claim 1  wherein the epoxidized ester is epoxidized 2-ethylhexyl tallate  
     
     
         8 . The composition of  claim 1  wherein the epoxidized ester is an epoxidized vegetable oil.  
     
     
         9 . The composition of  claim 1  wherein the epoxidized ester is selected from the group consisting of epoxidized soybean oil, epoxidized canola oil, and mixtures thereof.  
     
     
         10 . The composition of  claim 2  wherein the corrosive additive is glycerol monooleate.  
     
     
         11 . The composition of  claim 2  wherein the corrosive additive is selected from the group consisting of dithiocarbamates and thiuram disulfides.  
     
     
         12 . The composition of  claim 2  wherein the corrosive additive is a 4-imidazolidine thione.  
     
     
         13 . The composition of  claim 2  wherein the corrosive additive is selected from the group consisting of hydrazides, succinylhydrazides, 1,3,4-oxadiazole-2(3H)-thione, 1,3,4-thiadiazolane-2-thione, 2,3-dihydro-1,3,4-oxadiazole, and amides derived from C 6 -C 50  carboxylic acids.  
     
     
         14 . The composition of  claim 2  wherein the corrosive additive is selected from the group consisting of partially hydrolyzed vegetable oils, full and partial esterification products of diols and polyols with and C 6 -C 36  carboxylic acids and mixtures thereof, and esters of hydroxypolycarboxylic acids.  
     
     
         15 . The composition of  claim 2  wherein the corrosive additive is a triester of citric acid.  
     
     
         16 . The composition of  claim 2  wherein the corrosive additive is glycerol monooleate and the epoxidized ester is epoxidized 2-ethylhexyl oleate.  
     
     
         17 . A method for improving the anti-corrosive, anti-fatigue, and anti-wear properties of lubricants and hydrocarbon fuels comprising adding to said lubricants and hydrocarbon fuels a functional property-improving amount of at least one at least one epoxidized ester of the formula:  
       
         
           
           
               
               
           
         
       
       wherein: 
 m is 1 to 36;  
 R 1  and R 2  are independently selected hydrocarbyl groups, optionally substituted with alkyl, cycloalkyl, alkenyl, aryl or alkoxy groups, and optionally containing OH, ether, or epoxide functionalities,  
 or R 1  is a polyol residue selected from the group consisting of  
                     wherein:    
 n is 0 to about 12;  
 R 4 , R 5 , and R 9  are independently selected from the group consisting of hydrogen and hydrocarbyl;  
 R 6  is selected from the group consisting of linear alkylene, branched alkylene, linear alkenyl, and branched alkenyl; and  
 R 3 , R 7 , and R 8  are independently selected from the group consisting of hydrogen and an acyl group of the formula:  
                     
 wherein R 10  is hydrocarbyl, which may be further substituted.  
 
     
     
         18 . The method of  claim 17  wherein the epoxidized ester is an epoxidized ester of a C 6 -C 22  unsaturated or polyunsaturated carboxylic acid or mixtures thereof.  
     
     
         19 . The method of  claim 17  wherein the epoxidized ester is an epoxidized ester of oleic or linoleic acid, or a mixture thereof.  
     
     
         20 . The method of  claim 17  wherein the epoxidized ester is epoxidized 2-ethylhexyl tallate