Lubricating Compositions

Abstract

A lubricating composition suited for use in lubricating a driveline device 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;   a dispersant; 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  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  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 polyolefin-substituted bridged hydroxyaromatic compound or salt thereof 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 C 8  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 1 , 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 1 , 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 lubricant  claim 1  further comprising at least one of a phosphorus-containing antiwear agent comprising a non-ionic phosphorus compound; an amine salt of a phosphorus compound; a calcium-containing detergent; another phenate detergent; a sulphur-containing extreme pressure agent; a sulphur-containing corrosion inhibitor; or combinations thereof. 
     
     
         29 . The lubricating composition  claim 1  further comprising from about 0.05 to about 3 wt % of a C2-C18 di- or tri-hydrocarbyl phosphite, based on the total weight of said lubricant. 
     
     
         30 . The lubricating composition  claims 1  further comprising less than 2000 ppm zinc based on a total weight of said lubricant. 
     
     
         31 . The lubricating composition of  claim 1 , wherein the lubricant is substantially free of to free of a phenol alkylated with oligomers of propylene. 
     
     
         32 . A method of lubricating a manual transmission comprising supplying the lubricant composition of  claim 1  to said manual transmission. 
     
     
         33 . The method of  claim 32 , wherein the lubricating composition further comprises: a thiadiazole and a phosphorous containing antiwear agent. 
     
     
         34 . A method of lubricating automatic transmission comprising supplying the lubricating composition of  claim 1  to said automatic transmission. 
     
     
         35 . The method of  claim 34 , wherein the lubricating composition further comprises: a thiadiazole and a phosphorous containing antiwear agent. 
     
     
         36 . A method of lubricating an off-highway vehicle comprising supplying the lubricating composition of  claim 1  to said off-highway vehicle. 
     
     
         37 . The method of  claim 36 , wherein the lubricating composition further comprises: a zinc dialkyl dithiophosphate antiwear agent 
     
     
         38 . The method of  claim 37 , wherein the vehicle is a farm-tractor vehicle or a construction vehicle. 
     
     
         39 . A method of lubricating a highway vehicle comprising supplying the lubricating composition of  claim 1  to said off-highway vehicle. 
     
     
         40 . The method of  claim 39 , wherein the lubricating composition further comprises: a sulfurized olefin; a thiadiazole; and a phosphorous containing antiwear agent. 
     
     
         41 . A lubricating composition comprising:
 an oil of lubricating viscosity;   a dispersant;   a sulfurized olefin;   a thiadazole;   a phosphorous-containing anti-wear agent; and   a bridged phenate unit represented by the formula   
       
         
           
           
               
               
           
         
         and salts thereof, 
         where each R 1  and each R 2  represents a polyolefin group having a number average molecular weight of 200 to 500, or 300 to 400; 
         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.