Stabilized Blends Containing Friction Modifiers

Abstract

The present invention relates to functional fluid compositions containing friction modifiers, and specifically stable compositions containing friction modifiers with limited solubility in and/or limited compatibility with the functional fluids with which they are used. In particular the present invention deals with functional fluids used in internal combustion engines, such as engine oils, and phosphorus-containing friction modifiers, where the friction modifier is present in the functional fluid composition at levels that would otherwise cause the composition to be unstable and/or hazy.

We claim: 
     
         1 . A composition comprising:
 (a) a medium comprising a solvent, a functional fluid, an additive concentrate or combinations thereof; and   (b) a friction modifier component comprising a phosphorus-containing compound that is not fully soluble in the medium; and   (c) a stabilizing component that is soluble in (a) and that interacts with (b) such that (b)'s solubility in (a) is improved;   wherein components (b) and (c), or (b) alone, are present in component (a) in the form of dispersed particles having an average diameter of less than 10 microns; and   wherein the stabilizing component comprises a compound having at least one hydrogen-donating group, a least one hydrogen-accepting group, and at least one hydrocarbyl group, where the hydrogen-donating group and the hydrogen-accepting group are not separated by more than 8 bonds, where said bonds include covalent and ionic bonds.   
     
     
         2 . The composition of  claim 1  wherein component (c), the stabilizing component, comprises:
 (i) a quaternary salt comprising the reaction product of (a) hydrocarbyl-substituted compound having a tertiary amino group and (b) a quaternizing agent suitable for converting the tertiary amino group of (a) to a quaternary nitrogen, wherein the quaternizing agent is selected from the group consisting of dialkyl sulfates, benzyl halides, hydrocarbyl substituted carbonates; hydrocarbyl epoxides in combination with an acid or mixtures thereof; 
 (ii) a poly(hydroxycarboxylic acid) amide salt derivative represented by the formula [Y—CO[O-A-CO] n —Z r —R + ] m pX q-  wherein Y is hydrogen, a hydrocarbyl group or a substituted hydrocarbyl group, A is a divalent hydrocarbyl group, n is from 1 to 100, m is from 1 to 4, q is from 1 to 4 and p is an integer such that pq=m, Z is a divalent bridging group which is attached to the carbonyl group through a nitrogen atom, r is 0 or 1, R +  is an ammonium group and X q-  is an anion; 
 (ii) a high molecular weight polyetheramine prepared by reacting one unit of a hydroxy-containing hydrocarbyl compound with two or more units of butylene oxide to form a polyether intermediate, and aminating the polyether intermediate by reacting the polyether intermediate with an amine or with acrylonitrile and hydrogenating the reaction product of the polyether intermediate and acrylonitrile; 
 (iii) an alkanolamine substituted phenol where the phenol contains a hydrocarbyl substituent; 
 (iv) a low molecular weight acylated nitrogen compound derived from an alkyl succinic anhydride and an alkanolamine; 
 (v) a fatty amine salt of a salicylic acid; 
 or any combination thereof. 
 (vi) a nitrogen-containing dispersant or borated version thereof having at least one of the following properties: (a) the dispersant includes at least one hydrocarbyl group containing 10 to 500 carbon atoms, (b) the dispersant has a TBN, as defined by ASTM D4739, of at least 10, (c) the dispersant contains at least 0.1% weight boron, and (d) the dispersant has a N:CO ratio of greater than 0.7; 
 (vii) an alkyl imidazoline comprising the reaction product of a polyethylene polyamine and a fatty acid; 
 or combinations thereof. 
 
     
     
         3 . The composition of  claim 2  wherein the hydrocarbyl-substituted compound having a tertiary amino group used to prepare the quaternary salt comprises:
 (1) the condensation product of a hydrocarbyl-substituted acylating agent and a compound having an oxygen or nitrogen atom capable of condensing with said acylating agent and said condensation product further having a tertiary amino group; 
 (2) a polyalkene-substituted amine having at least one tertiary amino group; 
 (3) a Mannich reaction product having a tertiary amino group, said Mannich reaction product being prepared from the reaction of a hydrocarbyl-substituted phenol, an aldehyde, and an amine; 
 (4) a polyester containing a tertiary amino group; 
 
       or any combination thereof. 
     
     
         4 . The composition of  claim 2  wherein the A in the formula of the poly(hydroxycarboxylic acid) amide salt derivative is fully saturated. 
     
     
         5 . The composition of  claim 2  wherein the high molecular weight polyetheramine is represented by the formula R(OCH 2 CHR 1 ) x A wherein R is a C 6  to C 30  alkyl group or a C 6  to C 30  alkyl-substituted phenyl group; R 1  is ethyl; x is a number from 5 to 50; and A is —OCH 2 CH 2 CH 2 NH 2  or —NR 2 R 3  wherein R 2  and R 3  are independently hydrogen, a hydrocarbyl group, or —(R 4 NR 5 ) y R 6  wherein R 4  is an alkylene group having 2 to 10 carbon atoms, R 5  and R 6  are independently hydrogen or a hydrocarbyl group, and y is a number from 1 to 7. 
     
     
         6 . The composition of  claim 1  wherein the turbidity of the overall composition is improved, as defined by a lower JTU and/or NTU value compared to the same composition that does not contain (c), the stabilizing component. 
     
     
         7 . The composition of  claim 1  wherein (b), the friction modifier component comprises a phosphate, a phosphite, a thiophosphate, an amine salt of any of these materials, or any combination thereof. 
     
     
         8 . The composition of  claim 1  wherein (b), the friction modifier component, comprises a phosphorus-containing compound represented by the formula:
   (X 1 ═) a P(X 2   b —R) 3  
 
 
       or a salted version thereof wherein: each X 1  is independently O or S, a is 0 or 1, each X 2  is independently O or S, b is 0 or 1, and R is H or a hydrocarbyl group with the proviso that at least one of the R groups is a hydrocarbyl group containing at least 1 carbon atom. 
     
     
         9 . The compositions of  claim 1  wherein the friction modifier further comprises: (i) a hydrocarbyl phosphoric acid or acid ester; (ii) an amine salt thereof; or combinations thereof. 
     
     
         10 . The composition of  claim 1  wherein the amount of component (b) in the overall composition is at least 0.5 percent by weight. 
     
     
         11 . A process of preparing a clear and stable composition comprising:
 (a) a medium comprising a solvent, a functional fluid, an additive concentrate, or combinations thereof; and   (b) a friction modifier component comprising a phosphorus-containing compound that is not fully soluble in the medium; and   (c) a stabilizing component that is soluble in (a) and that interacts with (b) such that (b)'s solubility in (a) is improved;   said method comprising the steps of:   I. adding components (b) and (c) to component (a) wherein component (b) is present in the overall composition at a level of no less than 0.15 percent by weight;   II. mixing the components so that components (b) are present in component (a) in the form of dispersed particles having an average diameter of less than 10 microns; and   wherein the stabilizing component comprises a compound having at least one hydrogen-donating group, a least one hydrogen-accepting group, and at least one hydrocarbyl group, where the hydrogen-donating group and the hydrogen-accepting group are not separated by more than 8 bonds, wherein said bonds include covalent and ionic bonds.   
     
     
         12 . The process of  claim 11  wherein component (c), the stabilizing component, comprises:
 (i) a quaternary salt comprising the reaction product of (a) the condensation product of a hydrocarbyl-substituted acylating agent and a compound having an oxygen or nitrogen atom capable of condensing with said acylating agent and said condensation product further having a tertiary amino group and (b) a quaternizing agent suitable for converting the tertiary amino group of (a) to a quaternary nitrogen, wherein the quaternizing agent is selected from the group consisting of dialkyl sulfates, benzyl halides, hydrocarbyl substituted carbonates; hydrocarbyl epoxides in combination with an acid or mixtures thereof; 
 (ii) a poly(hydroxycarboxylic acid) amide salt derivative represented by the formula [Y—CO[O-A-CO] n —Z r —R + ] m pX q-  wherein Y is hydrogen or a hydrocarbyl group, A is a divalent hydrocarbyl group, n is from 1 to 100, m is from 1 to 4, q is from 1 to 4 and p is an integer such that pq=m, Z is a divalent bridging group which is attached to the carbonyl group through a nitrogen atom, r is 0 or 1, R +  is an ammonium group and X q-  is an anion; 
 (ii) a high molecular weight polyetheramine prepared by reacting one unit of a hydroxy-containing hydrocarbyl compound with two or more units of butylene oxide to form a polyether intermediate, and aminating the polyether intermediate by reacting the polyether intermediate with an amine or with acrylonitrile and hydrogenating the reaction product of the polyether intermediate and acrylonitrile; 
 (iii) an alkanolamine substituted phenol where the phenol contains a hydrocarbyl substituent; 
 (iv) a low molecular weight acylated nitrogen compound derived from an alkyl succinic anhydride and an alkanolamine; 
 (v) a fatty amine salt of a salicylic acid; 
 or any combination thereof. 
 (vi) a nitrogen-containing dispersant or borated version thereof having at least one of the following properties: (a) the dispersant includes at least one hydrocarbyl group containing 10 to 500 carbon atoms, (b) the dispersant has a TBN, as defined by ASTM D4739, of at least 10, (c) the dispersant contains at least 0.1% weight boron, and (d) the dispersant has a N:CO ratio of greater than 0.7; 
 (vii) an alkyl imidazoline comprising the reaction product of a polyethylene polyamine and a fatty acid; 
 or combinations thereof. 
 
     
     
         13 . The process of  claim 11  wherein the clarity of the resulting mixture is improved, as defined by a lower JTU and/or NTU value compared to the same composition that does not contain (c), the stabilizing component. 
     
     
         14 . The process of  claim 11  wherein (b), the friction modifier component, comprises a phosphorus-containing compound represented by the formula:
   (X 1 ═) a P(X 2   b —R) 3  
 
 
       or a salted version thereof wherein: each X 1  is independently O or S, a is 0 or 1, each X 2  is independently O or S, b is 0 or 1, and R is H or a hydrocarbyl group with the proviso that at least one of the R groups is a hydrocarbyl group containing at least 1 carbon atom. 
     
     
         15 . The process of  claim 11  wherein (b), the friction modifier component, comprises: (i) a hydrocarbyl phosphoric acid or acid ester; (ii) an amine salt thereof; or combinations thereof.