Lubricating oil with enhanced piston cleanliness control

Abstract

Provided are formulations, methods of making, and methods of using one or more reaction products of polyisobutylenes and monounsaturated acylating agents of the present invention in a low sulfur, low sulfated ash, and low phosphorus lubricant to enhance piston cleanliness in internal combustion engines.

1 . A lubricant composition suitable for use in an internal combustion engine, which comprises an admixture of:
 (a) a major amount of an oil of lubricating viscosity;   (b) one or more ashless dispersants;   (c) one or more metal-containing detergents; and   (d) a piston-cleanliness-enhancing amount of at least one reaction product of a polyisobutylene and a monounsaturated acylating agents wherein the polyisobutylene has a number average molecular weight of about 200 to about 5000 Daltons;   wherein said lubricant composition has a sulfur content of at or below about 0.3 wt. %, a phosphorus content of at or below about 0.09 wt. %, and a sulfated ash content of at or below about 1.6 wt. %, based on the total weight of said lubricating oil composition.   
     
     
         2 . The lubricant composition of  claim 1 , wherein the reaction product of a polyisobutylene and a monounsaturated acylating agent is represented by either of the formulas: 
       
         
           
           
               
               
           
         
       
       wherein R 1  is a polyisobutylene chain with a number average molecular weight of about 200 to about 5000 Daltons; and R 2  is a carboxyl-containing group. 
     
     
         3 . The composition of  claim 1 , further comprising one or more additives selected from: antiwear agents, friction modifiers, antioxidants, corrosion -inhibitors, viscosity index improvers, anti-foaming agents, seal fixes, pour point depressants, and other multi-functional additives. 
     
     
         4 . The composition of  claim 1 , wherein the sulfur content of the composition is at or below about 0.2 wt. % based on the total weight of said composition. 
     
     
         5 . The composition of  claim 4 , wherein the sulfur content of the composition is at or below about 0.1 wt. %, based on the total weight of said composition. 
     
     
         6 . The composition of  claim 1 , wherein the phosphorus content of the composition is at or below about 0.08 wt. %, based on the total weight of said composition. 
     
     
         7 . The composition of  claim 6 , wherein the phosphorus content of the composition is at or below about 0.07 wt. %, based on the total weight of said composition. 
     
     
         8 . The composition of  claim 7 , wherein the phosphorus content of the composition is at or below about 0.05 wt. %, based on the total weight of said composition. 
     
     
         9 . The composition of  claim 1 , wherein the sulfated ash content of the composition is at or below about 1.0 wt. %, based on the total weight of said composition. 
     
     
         10 . The composition of  claim 9 , wherein the sulfated ash content of the composition is at or below about 0.8 wt. %, based on the total weight of said composition. 
     
     
         11 . The composition of  claim 10 , wherein the sulfated ash content of the composition is at or below about 0.5 wt. %, based on the total weight of said composition. 
     
     
         12 . The composition of  claim 11 , wherein the sulfated ash content of the composition is at or below about 0.45 wt. %, based on the total weight of said composition. 
     
     
         13 . The composition of  claim 1 , wherein the amount of the at least one reaction product of a PIB and a monounsaturated acylating agent is about 0.01 to about 5.0 wt. %, based on the total weight of the lubricant composition. 
     
     
         14 . The composition of  claim 13 , wherein the amount of the at least one reaction product of a PIB and a monounsaturated acylating agent is about 0.5 to about 4.0 wt. %, based on the total weight of the lubricant composition. 
     
     
         15 . The composition of  claim 14 , wherein the amount of the at least one reaction product of a PIB arid a monounsaturated acylating agent is about 1.0 to about 2.5 wt. %, based on the total weight of the lubricant composition. 
     
     
         16 . The composition of  claim 1 , wherein the PIB in the at least one reaction product of a PIB and a monounsaturated acylating agent has a number average molecular weight of about 500 to about 4500 Daltons. 
     
     
         17 . The composition of  claim 16 , wherein the PIB has a number average molecular weight of about 1000 to about 3500 Daltons. 
     
     
         18 . The composition of  claim 17 , wherein the FIB has a number average molecular weight of about 2300 Daltons. 
     
     
         19 . The composition of  claim 17 , wherein the PIB has a number average molecular weight of about 1300 Daltons. 
     
     
         20 . The composition of  claim 1 , wherein the PIB in the at least one reaction product of a PIB and a monounsaturated acylating agent is a highly reactive PIB. 
     
     
         21 . The composition of  claim 1 , wherein the monounsaturated acylating agent is derived from an anhydride or an anhydride-producing material. 
     
     
         22 . The composition of  claim 21 , wherein the monounsaturated acylating agent is derived from maleic anhydride. 
     
     
         23 . The composition of  claim 1 , wherein the one or more metal-containing detergents is present in an amount of about 0.05 to about 16 mM. 
     
     
         24 . The composition of  claim 1 , wherein the ashless dispersant is a bissuccinimide derived from one or more PIBSAs. 
     
     
         25 . The composition of  claim 24 , wherein the ashless dispersant is a bissucinimide derived from a PIBS A wherein the PIB chain has a number average molecular weight of about 2300 Daltons. 
     
     
         26 . The composition of  claim 24 , wherein the ashless dispersant is a bissucinimde derived from a mixture of a first PIBSA wherein the PIB chain has a number average molecular weight of about 2300 Daltons, and a second PIBSA wherein the PIB chain has a number average molecular weight of about 1300Daltons. 
     
     
         27 . The composition of  claim 24 , wherein the bissuccinimide is present in an amount of about 0.5 wt. % to about 1.0 wt. %. 
     
     
         28 . The composition of  claim 3 , wherein the antiwear agent is a metal dicarbyldithiophosphate. 
     
     
         29 . The composition of  claim 28 , wherein the metal dicarbyldithiophosphate is zinc dialkylthiophosphate. 
     
     
         30 . The composition of  claim 29 , wherein the amount of zinc dialkylthiophosphate present contributes from about 0.03 to about 0.075 wt. % of phosphorus to the composition. 
     
     
         31 . The composition of  claim 1 , wherein the ashless dispersant contributes about 0.08 to about 0.12 wt. % of nitrogen to the composition. 
     
     
         32 . The composition of  claim 1 , wherein the metal-containing detergent is a calcium overbased detergent. 
     
     
         33 . The composition of  claim 32 , wherein the calcium overbased detergent is selected from: calcium sulfonates, calcium phenates, calcium salicylates, calcium stearates, and mixtures thereof. 
     
     
         34 . The composition of  claim 3 , wherein the antioxidant is a diphenylamine. 
     
     
         35 . The composition of  claim 34 , wherein the diphenylamine is present from about 0.05 wt. % to about 5.00 wt. %, based on the total weight of the composition. 
     
     
         36 . The composition of  claim 3 , wherein the friction modifier is a molybdenum succinimide complex. 
     
     
         37 . The composition of  claim 36 , wherein the molybdenum succinimide complex is present in an amount of from about 0.15 to about 0.55 wt. %, based on the total weight of the composition. 
     
     
         38 . The composition of  claim 3 , wherein the viscosity index modifier is an ethylene polymer or a polyalkyl methacrylate copolymer. 
     
     
         39 . A method of improving piston cleanliness in an internal combustion engine, said method comprising:
 operating said internal combustion engine with, a low phosphorus, low sulfur and low sulfated, ash lubricating oil composition, which comprises;   (a) a major amount of a base oil of lubricating viscosity;   (b) one or more ashless dispersants;   (c) one or more metal-containing detergents; and   (d) a piston cleanliness-enhancing amount of at least one reaction product of a PIB and a monounsaturated acylating agent, wherein the PIB has a number average molecular weight of about 200 to about 5000 Daltons;   wherein said low phosphorus, low sulfur and low sulfated ash oil composition has a sulfur content of at or below about 0.3 wt. %, a phosphorus content of at or below about 0.09 wt. %, and a sulfated ash content of at or below about 1.6 wt. %, based on the total weight of the composition.   
     
     
         40 . The method according to  claim 39 , wherein the reaction product of a PIB and a monounsaturated acylating agent is represented by either of the formulas: 
       
         
           
           
               
               
           
         
       
       wherein R 1  is a PIB chain with a number average molecular weight of about 200 to about 5000 Daltons; and R 2  is a carboxyl-containing group. 
     
     
         41 . The method of  claim 39 , wherein the low phosphorus, low sulfur and low sulfated ash lubricating oil composition further comprises one or more additives selected from: antiwear agents, friction modifiers, antioxidants, corrosion inhibitors, pour point depressants, viscosity index modifiers, anti-foaming-agents, seal fixes, arid other multi-functional additives. 
     
     
         42 . The method of  claim 39 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfur content of at or below about 0.2 wt. %. 
     
     
         43 . The method of  claim 42 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfur content of at or below about 0.1 wt. %. 
     
     
         44 . The method of  claim 39 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a phosphorus content of at or below about 0.08 wt. %. 
     
     
         45 . The method of  claim 44 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a phosphorus content of at or below about 0.07 wt. %. 
     
     
         46 . The method of  claim 45 , wherein the low phosphorus, low sulfur and low sulfated, ash oil composition has a phosphorus content of at of below about 0.05 wt. %. 
     
     
         47 . The method of  claim 39 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfated ash content at or below about 1.0 wt. %. 
     
     
         48 . The method of  claim 47 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfated ash content at or below about 0.8 wt. %. 
     
     
         49 . The method of  claim 48 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfated ash content at or below about 0.5 wt. %. 
     
     
         50 . The method of  claim 49 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfated ash content at or below about 0.45 wt. %. 
     
     
         51 . The method of  claim 39 , wherein the amount of the at least one reaction product of a PIE and a monounsaturated acylating agent is about 0.01 to about 5.00 wt. %, based on the total weight of the lubricant composition. 
     
     
         52 . The method of  claim 51 , wherein the amount of the at least one reaction product of a PIB and a monounsaturated acylating agent is about 0.50 to about 4.00 wt. %, based on the total weight of the lubricant composition. 
     
     
         53 . The method of  claim 52 , wherein the amount of the at least one reaction product of a PIB and a monounsaturated acylating agent is about 1.00 to about 2.50 wt. %, based on the total weight of the lubricant composition. 
     
     
         54 . A method of operating an internal combustion engine provided with exhaust gas after-treatment devices, which method comprises lubricating said engine with a lubricating, oil composition according to  claim 1 . 
     
     
         55 . A method according to  claim 54 , wherein said internal combustion engine is selected from: (1) a light duty diesel-fueled internal combustion engine; (2) a heavy duty diesel-fueled internal combustion engine; and (3) a gasoline-fueled internal combustion engine. 
     
     
         56 . A method according to  claim 54 , wherein said exhaust gas after-treatment devices are one or more devices selected from particulate traps and catalytic converters. 
     
     
         57 . A method of making a lubricant composition comprising blending the following components:
 (a) a major amount of an oil of lubricating viscosity;   (b) one or more ashless dispersants;   (c) one or more metal-containing detergents; and   (d) at least one reaction product of a PIB and a monounsaturated acylating agent, wherein the PIB has a number average molecular weight of about 200 to about 5000 Daltons;   and resulting in a lubricant composition with a sulfur content of at or below about 0.3 wt. %, a phosphorus content of at or below about 0.09 wt. %, and a sulfated ash content of at or below about 1.6 wt. %, based on the total weight of the lubricant composition.   
     
     
         58 . The method according to  claim 57 , wherein the reaction product of a PIB and a monounsaturated acylating agent is represented by either of the formulas: 
       
         
           
           
               
               
           
         
       
       wherein R 1  is a PIB chain with a number average molecular weight of about 200 to about 5000 Daltons; and R 2  is a carboxyl-containing group. 
     
     
         59 . The method of  claim 57 , where one or more additives selected from: antiwear agents, friction modifiers, antioxidants, viscosity index modifiers, corrosion inhibitors, anti-foaming agents, seal fixes, pour point depressants, and other multi-functional additives, are further blended into said lubricant composition. 
     
     
         60 . The method of  claim 57 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfur content of at or below about 0.2 wt. %. 
     
     
         61 . The method of  claim 60 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfur content of at or below about 0.1 wt. %. 
     
     
         62 . The method of  claim 57 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a phosphorus content of at or below about 0.08 wt. %. 
     
     
         63 . The method of  claim 62 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a phosphorus content of at or below about 0,07 wt. %. 
     
     
         64 . The method of  claim 63 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a phosphorus content of at or below about 0.05 wt. %. 
     
     
         65 . The method of  claim 57 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfated ash content at or below about 1.0 wt. %. 
     
     
         66 . The method of  claim 65 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfated ash content at or below about 0.8 wt. %. 
     
     
         67 . The method of  claim 66 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfated ash content at or below about 0.5 wt. %. 
     
     
         68 . The method of  claim 67 , wherein the low phosphorus, low sulfur and low sulfated ash oil composition has a sulfated ash content at or below about 0.45 wt. %. 
     
     
         69 . The method of  claim 57 , wherein the amount of the at least one reaction product of a PIB and a monounsaturated acylating agent is about 0.01 to about 5.00 wt. %, based on the total weight of the lubricant composition. 
     
     
         70 . The method of  claim 69 , wherein the amount of the at least one reaction product of a PIB and a monounsaturated acylating agent is about 0.5 to about 4.0 wt. %, based on the total weight of the lubricant composition. 
     
     
         71 . The method of  claim 70 , wherein the amount of the at least one reaction product of a PIB and a monounsaturated acylating agent is about 1.0 to about 2.5 wt. %, based on the total weight of the lubricant composition.