Lubricating Compositions

Abstract

A lubricating composition suited to use in lubricating an internal combustion engine includes an oil of lubricating viscosity and a compound comprising a polyolefin-substituted bridged hydroxyaromatic compound or metal salt thereof, wherein the polyolefin is derived from a isobutylene having a number average molecular weight of 150 to 800.

What is claimed is: 
     
         1 . A lubricating composition comprising:
 an oil of lubricating viscosity; and   a compound comprising a polyolefin-substituted bridged hydroxyaromatic compound 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 branched alkene comprises isobutylene. 
     
     
         3 . 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. 
     
     
         4 . The lubricating composition of  claim 1 , wherein the polyolefin has a number average molecular weight of 150 to 400. 
     
     
         5 . The lubricating composition of  claim 1 , wherein the compound is a metal salt or pnictogen salt. 
     
     
         6 . The lubricating composition of  claim 1  wherein the polyolefin is prepared in the absence of a chain transfer agent and has a polydispersity greater than 1.5. 
     
     
         7 . The lubricating composition of  claim 6 , wherein the metal in the salt comprises calcium. 
     
     
         8 . The lubricating composition of  claim 1 , wherein the metal is overbased. 
     
     
         9 . The lubricating composition of  claim 1 , wherein the compound is bridged with a sulfide bridge. 
     
     
         10 . The lubricating composition of  claim 1 , wherein the compound is bridged with an alkylene bridge. 
     
     
         11 . The lubricating composition of  claim 1 , wherein the compound is a bridged metal phenate. 
     
     
         12 . The lubricating composition of  claim 1 , wherein the compound is free of C8 and higher unbranched alkyl chains. 
     
     
         13 . The lubricating composition of  claim 1 , wherein the compound includes a bridged phenate unit represented by the formula: 
       
         
           
           
               
               
           
         
         and salts thereof, 
         where each R1 and each R2 represents a polyolefin group; 
         X represents a bridging group; 
         Y and Z each represent a terminal group; 
         each n is at least 1; 
         m is at least 1; and 
         p is at least 1. 
       
     
     
         14 . The lubricating composition of  claim 13 , wherein the compound is not coupled with cresol. 
     
     
         15 . The lubricating composition of  claim 13 , wherein n is 1. 
     
     
         16 . The lubricating composition of  claim 13 , wherein each R1 and R2 is independently a polyolefin of 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. 
     
     
         17 . The lubricating composition of  claim 13 , wherein each R1 and each R2 is a polyisobutylene. 
     
     
         18 . The lubricating composition of  claim 1 , wherein each R1 is a 300-400 MW polyisobutylene. 
     
     
         19 . The lubricating composition of  claim 1 , wherein the compound has a weight-average molecular weight of 550-5600 in its unsalted form. 
     
     
         20 . The lubricating composition of  claim 1 , wherein the compound has a weight average molecular weight of up to 2800 in its unsalted form. 
     
     
         21 . The lubricating composition of  claim 1 , wherein the compound is at least 0.01 wt. % of the lubricating composition. 
     
     
         22 . The lubricating composition of  claim 21 , wherein the compound 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. 
     
     
         23 . The lubricating composition of  claim 21 , wherein the compound 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. 
     
     
         24 . 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. 
     
     
         25 . The lubricating composition of  claim 1 , wherein the oil of lubricating viscosity is at least 10 wt. % of the lubricating composition. 
     
     
         26 . The lubricating composition of  claim 25 , wherein the oil of lubricating viscosity is at least 30 wt. % of the lubricating composition. 
     
     
         27 . The lubricating composition of  claim 1 , wherein the oil of lubricating viscosity is up to 95 wt. % of the lubricating composition. 
     
     
         28 . 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. 
     
     
         29 . The lubricating composition of  claim 1 , wherein the lubricating composition has a SAE viscosity grade of XW-Y, wherein X is selected from 0, 5, 10 and 15; and Y is selected from 16, 20, 30, or 40. 
     
     
         30 . A lubricating composition comprising:
 an oil of lubricating viscosity; and   a compound which is the reaction product of a polyolefin and a hydroxyaromatic compound, the compound including at least one bridge between first and second hydroxyaromatic groups and including a counterion and 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.   
     
     
         31 . A method of lubricating a mechanical device comprising supplying to the device the lubricating composition of  claim 1 . 
     
     
         32 . The method of  claim 31 , wherein the mechanical device comprises an engine or driveline device. 
     
     
         33 . The method of  claim 31 , wherein the mechanical device comprises a heavy duty diesel or marine diesel engine. 
     
     
         34 . A method of forming a lubricating composition comprising:
 reacting a phenol with a branched polyolefin to form a polyolefin-substituted phenol 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;   bridging the polyolefin-substituted phenol with a bridging agent selected from sulfur and an aldehyde;   optionally, reacting the polyolefin-substituted phenol or bridged polyolefin-substituted phenol with a metal base to form a salt; and   combining the bridged polyolefin-substituted phenol or salt with an oil of lubricating viscosity.   
     
     
         35 . The method of  claim 34 , wherein the reaction between the phenol and the branched polyolefin is carried out in the presence of a catalyst. 
     
     
         36 . The method of  claim 34 , wherein a ratio of phenol to polyolefin in the reaction is at least 2:1. 
     
     
         37 . Use of the lubricating composition of  claim 1  for lubricating a mechanical device.