Lubricating Oil Compositions

Abstract

Use of an oil-soluble hydrocarbyl phenol aldehyde condensate as an antiwear additive in a lubricating oil composition. The oil-soluble hydrocarbyl phenol aldehyde condensate has the following structure: wherein n is 0 to 10, preferably 1 to 8, more preferably 2 to 6, and most preferably 3 to 5; Y is a divalent bridging group, and is preferably a hydrocarbyl group, preferably having from 1 to 4 carbon atoms; and R is a hydrocarbyl group having from 4 to 30, preferably 8 to 18, and most preferably 9 to 15 carbon atoms.

1 . A method for reducing wear caused by operation of a marine crosshead diesel engine which method comprises:
 lubricating cylinders of said marine crosshead diesel engine with a marine diesel cylinder lubricant comprising an effective amount of a metal-free, oil-soluble hydrocarbyl phenol aldehyde condensate having the following structure:   
       
         
           
           
               
               
           
         
       
       wherein n is 0 to 10; Y is a divalent bridging group; and R is a hydrocarbyl group having from 4 to 30 carbon atoms. 
     
     
         2 . (canceled) 
     
     
         3 . The method of  claim 1 , wherein the hydrocarbyl phenol aldehyde condensate has a number average molecular weight in the range of 800 to 4500. 
     
     
         4 . The method of  claim 1 , wherein the condensate includes less than 5.0% mass of unreacted hydrocarbyl phenol. 
     
     
         5 . The method of  claim 1 , wherein the hydrocarbyl phenol aldehyde condensate is produced by the condensation reaction between at least one aldehyde or ketone or reactive equivalent thereof and a hydrocarbyl phenol, in the presence of an acid catalyst. 
     
     
         6 . The method of  claim 1 , wherein the hydrocarbyl group in the hydrocarbyl phenol aldehyde condensate is branched. 
     
     
         7 . The method of  claim 1 , wherein the hydrocarbyl phenol aldehyde condensate is a hydrocarbyl phenol formaldehyde condensate. 
     
     
         8 . The method of  claim 1 , wherein the hydrocarbyl phenol aldehyde condensate is tetrapropenyl phenol formaldehyde condensate. 
     
     
         9 . The method of  claim 1 , wherein said marine diesel cylinder lubricant includes at least one of the following additives: a detergent, a dispersant, an antioxidant, an antiwear additive, a pour point depressant, an antifoaming agent, a viscosity index improver, a dye, a metal deactivator, a demulsifier, or a mixture thereof. 
     
     
         10 . The method of  claim 1 , wherein said marine diesel cylinder lubricant has a TBN of greater than 55 mg KOH/g, as determined by ASTM D2896. 
     
     
         11 . The method of  claim 1 , wherein said hydrocarbyl phenol aldehyde condensate is sulphur-free. 
     
     
         12 . The method of  claim 1 , wherein said marine diesel cylinder lubricant comprises from about 0.1 to 20 mass % of said hydrocarbyl phenol aldehyde condensate. 
     
     
         13 . A marine diesel cylinder lubricant for a crosshead marine diesel engine, having a TBN of greater than 55 mg KOH/g, as determined by ASTM D2896, and comprising oil of lubricating viscosity and a metal-free, oil-soluble hydrocarbyl phenol aldehyde condensate having the following structure: 
       
         
           
           
               
               
           
         
       
       wherein n is 0 to 10; Y is a divalent bridging group; and R is a hydrocarbyl group having from 4 to 30 carbon atoms. 
     
     
         14 . The marine diesel cylinder lubricant of  claim 13 , wherein the hydrocarbyl phenol aldehyde condensate has a number average molecular weight in the range of 800 to 4500. 
     
     
         15 . The marine diesel cylinder lubricant of  claim 13 , wherein the condensate includes less than 5.0% mass of unreacted hydrocarbyl phenol. 
     
     
         16 . The marine diesel cylinder lubricant of  claim 13 , wherein the hydrocarbyl phenol aldehyde condensate is produced by the condensation reaction between at least one aldehyde or ketone or reactive equivalent thereof and a hydrocarbyl phenol, in the presence of an acid catalyst. 
     
     
         17 . The marine diesel cylinder lubricant of  claim 1 , wherein the hydrocarbyl group in the hydrocarbyl phenol aldehyde condensate is branched. 
     
     
         18 . The marine diesel cylinder lubricant of  claim 13 , wherein the hydrocarbyl phenol aldehyde condensate is a hydrocarbyl phenol formaldehyde condensate. 
     
     
         19 . The marine diesel cylinder lubricant of  claim 13 , wherein the hydrocarbyl phenol aldehyde condensate is tetrapropenyl phenol formaldehyde condensate. 
     
     
         20 . The marine diesel cylinder lubricant (MDCL) of  claim 13 , further comprising at least one of the following additives: a detergent, a dispersant, an antioxidant, an antiwear additive, a pour point depressant, an antifoaming agent, a viscosity index improver, a dye, a metal deactivator, a demulsifier, or a mixture thereof. 
     
     
         21 . The marine diesel cylinder lubricant of  claim 13 , wherein said hydrocarbyl phenol aldehyde condensate is sulphur-free. 
     
     
         22 . The marine diesel cylinder lubricant of  claim 13 , comprising from about 0.1 to 20 mass % of said hydrocarbyl phenol aldehyde condensate.