Low molecular weight amide/ester containing quaternary ammonium salts

Abstract

The present technology is related to amide or ester containing quaternary ammonium salts having a hydrocarbyl substituent of number average molecular weight ranging from 300 to 750, and the use of such quaternary ammonium salts in fuel compositions to improve the water shedding performance of the fuel composition.

What we claim: 
     
         1 . A composition comprising an ester or amide containing quaternary ammonium salt (“amide/ester quat”), wherein the amide/ester quat comprises the reaction product of:
 a) a quaternizable compound that is the reaction product of:
 (i) a hydrocarbyl-substituted acylating agent, wherein the hydrocarbyl-substituent has a number average molecular weight ranging from 300 to 650 and comprises at least one polyisobutenyl succinic anhydride or polyisobutenyl succinic acid, and 
 (ii) a nitrogen containing compound having an oxygen or nitrogen atom capable of reacting with said hydrocarbyl-substituted acylating agent to form an ester or amide, and further having at least one quaternizable amino group; and 
 
 b) a quaternizing agent comprising a hydrocarbyl epoxide or a hydrocarbyl epoxide in combination with an acid; and 
 wherein the reaction of a) and b) is essentially free of any additional acid component other than the acid group present in the acylating agent. 
 
     
     
         2 . The composition of  claim 1 , wherein the amide/ester quat comprises compounds having the structure: 
       
         
           
           
               
               
           
         
         wherein R 21  and R 22  are hydrocarbyl groups containing from 1 to 10 carbon atoms; R 23  is a hydrocarbylene group containing from 1 to 20 carbon atoms; R 24  is a hydrocarbyl group containing from 20 to 55 carbon atoms; X is a group derived from the quaternizing agent; and Y is oxygen or nitrogen. 
       
     
     
         3 . The composition of  claim 1 , wherein the hydrocarbyl-substituted acylating agent has a number average molecular weight ranging from 350 to 650. 
     
     
         4 . The composition of  claim 3 , wherein the hydrocarbyl-substituted acylating agent has a number average molecular weight ranging from 350 to 550. 
     
     
         5 . The composition of  claim 1 , further comprising a diesel fuel. 
     
     
         6 . The composition of  claim 5 , wherein the amide/ester quat is present in the diesel fuel at a treat rate of 5 to 1000 ppm. 
     
     
         7 . The composition of  claim 5 , wherein the diesel fuel further comprises at least one other additive that is a detergent, a dispersant, a demulsifier, a lubricity agent, a cold flow improver, an antioxidant, or a mixture thereof. 
     
     
         8 . The composition of  claim 7 , wherein the at least one other additive comprises at least one hydrocarbyl-substituted quaternary ammonium salt. 
     
     
         9 . The composition of  claim 8 , wherein the hydrocarbyl-substituent is a polyisobutylene having a number average molecular weight ranging from 100 to 5000. 
     
     
         10 . The composition of  claim 7 , wherein the at least one other additive comprises at least one detergent/dispersant that is an amphiphilic substance which possess at least one hydrophobic hydrocarbon radical with a number average molecular weight of 100 to 10000 and at least one polar moiety selected from (i) Mono- or polyamino groups having up to 6 nitrogen atoms, at least one nitrogen atom having basic properties; (ii) Hydroxyl groups in combination with mono or polyamino groups, at least one nitrogen atoms having basic properties; (v) Polyoxy-C2 to C4 alkylene moieties terminated by hydroxyl groups, mono- or polyamino groups, at least one nitrogen atom having basic properties, or by carbamate groups; (vii) Moieties derived from succinic anhydride and having hydroxyl and/or amino and/or amido and/or imido groups; and/or (viii) Moieties obtained by Mannich reaction of substituted phenols with aldehydes and mono- or polyamines. 
     
     
         11 . The composition of  claim 10 , wherein the at least one other additive comprises at least one Mannich compound. 
     
     
         12 . The composition of  claim 5 , further comprising at least one of a soap having a number average molecular weight (M n ) of less than 340, a polyisobutylene succinimide (PIBSI) having a number average molecular weight (M n ) of less than 400, or a mixture thereof. 
     
     
         13 . The composition of  claim 5 , further comprising from 0.01 to 25 ppm of a metal and from 1 to 12 ppm of a corrosion inhibitor. 
     
     
         14 . The composition of  claim 13 , wherein the corrosion inhibitor is an alkenyl succinic acid comprising at least one of dodecenyl succinic acid (DDSA), hexadecenyl succinic acid (HDSA), or mixtures thereof. 
     
     
         15 . A method of reducing and/or preventing injector deposits, said method comprising supplying the composition of  claim 5  to the engine and operating the engine. 
     
     
         16 . The method of  claim 15 , wherein the engine comprises a high pressure common rail injector system. 
     
     
         17 . A method of improving water shedding performance of a diesel duel, said method comprising adding the composition of  claim 1  to the diesel fuel.