Alkylphenol detergents

Abstract

The disclosed technology provides a lubricating composition comprising an oil of lubricating viscosity and a detergent comprising a polyolefin-substituted hydroxy-aromatic carboxylic acid or salt thereof, wherein the polyolefin is derived from a branched alkene having at least 4 carbon atoms and wherein the polyolefin has a number average molecular weight of 150 to 800. The invention further relates to a method of lubricating a mechanical device with the lubricant composition.

What is claimed: 
     
         1 . A lubricating composition comprising:
 (a) an oil of lubricating viscosity; and   (b) a detergent comprising a polyolefin-substituted hydroxy-aromatic carboxylic acid or salt thereof, wherein the polyolefin is derived from a branched alkene having at least 4 carbon atoms and wherein the polyolefin has a number average molecular weight of 150 to 800.   
     
     
         2 . The lubricating composition of  claim 1 , wherein the polyolefin-substituted hydroxyl-aromatic carboxylic acid is represented by the structure: 
       
         
           
           
               
               
           
         
       
       wherein R 1  represents the polyolefin and R 2  is selected from hydrogen or a hydrocarbyl group of 1 to 40 carbon atoms. 
     
     
         3 . The lubricating composition of  claim 2 , wherein R 2  is a second polyolefin derived from a branched alkene having at least 4 carbon atoms and wherein the polyolefin has a number average molecular weight of 150 to 800. 
     
     
         4 . The lubricating composition of  claim 1 , wherein the carboxylic acid is a hydroxybenzoic acid. 
     
     
         5 . The lubricating composition of  claim 1 , wherein the polyolefin-substituted hydroxy-aromatic carboxylic acid is an alkylsalicylate represented by the structure 
       
         
           
           
               
               
           
         
       
       where R represents the polyolefin. 
     
     
         6 . The lubricating composition of  claim 1 , wherein the branched alkene comprises isobutylene. 
     
     
         7 . The lubricating composition of  claim 1 , wherein the polyolefin includes a chain derived from at least 4, or at least 5, or up to 6, or up to 7, or up to 8, or up to 18 branched alkene units. 
     
     
         8 . The lubricating composition of  claim 1 , wherein the polyolefin has a number average molecular weight of 150 to 400. 
     
     
         9 . The lubricating composition of  claim 1 , wherein the detergent is a metal salt. 
     
     
         10 . The lubricating composition of  claim 9 , wherein the metal in the salt comprises calcium. 
     
     
         11 . The lubricating composition of  claim 9 , wherein the metal is overbased. 
     
     
         12 . The lubricating composition of  claim 1 , wherein the detergent is free of C8 and higher unbranched alkyl chains. 
     
     
         13 . The lubricating composition of  claim 1 , wherein the polyolefin contains 8 to 50 carbon atoms, or at least 10 carbon atoms, or at least 10 carbon atoms, or at least 12 carbon atoms, or at least 14 carbon atoms, or at least 16 carbon atoms, or at least 18 carbon atoms, or at least 20 carbon atoms, or at least 24 carbon atoms, or up to 40 carbon atoms, or up to 35 carbon atoms, or up to 30 carbon atoms. 
     
     
         14 . The lubricating composition of  claim 1 , wherein the polyolefin is a polyisobutylene. 
     
     
         15 . The lubricating composition of  claim 14 , wherein the polyisobutylene has a number average molecular weight of up to 600. 
     
     
         16 . The lubricating composition of  claim 15 , wherein the polyisobutylene has a number average molecular weight of up to 500. 
     
     
         17 . The lubricating composition of  claim 16 , wherein the polyisobutylene has a number average molecular weight of 300 to 400. 
     
     
         18 . The lubricating composition of  claim 1 , wherein the polyolefin-substituted hydroxy-aromatic carboxylic acid is at least 0.01 wt. % of the lubricating composition. 
     
     
         19 . The lubricating composition of  claim 18 , wherein the polyolefin-substituted hydroxy-aromatic carboxylic acid is at least 0.1 wt. %, or at least 0.5 wt. % or at least 1 wt. %, or at least 2 wt. % of the lubricating composition. 
     
     
         20 . The lubricating composition of  claim 18 , wherein the polyolefin-substituted hydroxy-aromatic carboxylic acid is up to 20 wt. % or up to 10 wt. %, or up to 5 wt. %, or up to 3 wt. %, or up to 2.5 wt. % of the lubricating composition. 
     
     
         21 . The lubricating composition of  claim 1 , wherein the oil of lubricating viscosity comprises at least one of an API Group I, II, III, IV, and V base oil. 
     
     
         22 . The lubricating composition of  claim 1 , wherein the oil of lubricating viscosity is at least 10 wt. % of the lubricating composition. 
     
     
         23 . The lubricating composition of  claim 22 , wherein the oil of lubricating viscosity is at least 30 wt. % of the lubricating composition. 
     
     
         24 . The lubricating composition of  claim 1 , wherein the oil of lubricating viscosity is up to 95 wt. % of the lubricating composition. 
     
     
         25 . The lubricating composition of  claim 1 , further comprising at least one of the group consisting of detergents, antioxidants, dispersants, antiwear agents, friction modifiers, corrosion inhibitors, and combinations thereof. 
     
     
         26 . A method of lubricating a mechanical device comprising supplying to the device the lubricating composition of  claim 1 . 
     
     
         27 . The method of  claim 26 , wherein the mechanical device comprises an engine or driveline device. 
     
     
         28 . The method of  claim 26 , wherein the mechanical device comprises a heavy duty diesel or marine diesel engine. 
     
     
         29 . The method of  claim 26 , wherein the mechanical device is a hydraulic system, turbine system, or circulating oil system. 
     
     
         30 . The method of  claim 27 , wherein the mechanical device is a transmission. 
     
     
         31 . The use of the lubricating composition of  claim 1 , for lubricating a mechanical device. 
     
     
         32 . A method of forming a lubricating composition comprising:
 (i) forming a polyolefin-substituted hydroxy-aromatic carboxylic acid wherein the polyolefin is derived from a branched alkene having at least 4 carbon atoms and wherein the polyolefin has a number average molecular weight of 150 to 800 to form a substrate;   (ii) optionally, reacting the substrate with a metal base in the presence of carbon dioxide to form a metal salt; and   (iii) combining the polyolefin-substituted hydroxy-aromatic carboxylic acid salt thereof with an oil of lubricating viscosity.