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 enhancing antiwear properties of a lubricating composition, which method comprises: 
 blending an oil-soluble hydrocarbyl phenol aldehyde condensate and a lubricating oil, the 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 . The method of  claim 1 , wherein the lubricating oil composition is suitable for use in a marine diesel engine.  
     
     
         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 the lubricating oil composition 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.