ORGANIC TUNGSTEN COMPLEXES
The present invention relates to lubricant compositions containing phosphorus and sulfur free organotungstates. The organotungstates are defined as either the reaction product of a mono- or diglyceride and a tungsten source, or as the reaction product of a secondary amine, a fatty acid derivative, and a tungsten source. These compositions exhibit improved antiwear, corrosion, and antioxidancy properties, particularly in low phosphorus and low sulfur environments.
1 . An organic tungsten complex prepared by reacting (a) a tungsten salt, wherein the tungsten salt is the reaction product of an acidic tungsten and a nitrogenous base; and (b) a fatty acid derivative.
2 . The organic tungsten complex according to claim 1 wherein the tungsten salt is an ammonium tungstate salt.
3 . The organic tungsten complex according to claim 1 wherein the fatty oil derivative is a reaction product of (a) a secondary amine and (b) a fatty oil or a fatty acid.
4 . The organic tungsten complex according to claim 3 wherein the fatty oil derivative is a monoglyceride.
5 . The organic tungsten complex according to claim 1 having the formula
wherein R1 and R2 may represent the same or different fatty oil residue; R3 and R4 may be the same or different, and each may be hydrogen, C1 to C25 straight or branched chain alkyl radicals, C1 to C12 alkoxy-(C6 alkylene) radicals, or C2 to C12 alkyl amino-(C2 to C6 alkylene) radicals; Q represents either nitrogen or oxygen; the sum of n+m is a value greater than or equal to 1; x is a value between 1 and 12; and y is a value greater than or equal to x.
6 . The organic tungsten complex according to claim 3 wherein the secondary amine is diethanolamine, 2-(2-aminoethyl)amino-ethanol or isodecyloxypropyl-1,3-diaminopropane.
7 . The organic tungsten complex according to claim 4 wherein the monoglyceride is glyceryl stearate.
8 . The organic tungsten complex according to claim 3 wherein the fatty oil is selected from the group consisting of tallow, coconut oil, corn oil, cornseed oil, linseed oil, peanut oil, palm oil, soybean oil, rapeseed oil, sunflower seed oil and mixtures thereof.
9 . The organic tungsten complex according to claim 2 wherein the nitrogenous base is selected from the group consisting of ammonium metatungstate, ammonium paratungstate, ammonium tungstate and mixtures thereof.
10 . The organic tungsten complex according to claim 1 wherein the nitrogenous base is a mono-, di-, or polyamine.
11 . The organic tungsten complex according to claim 10 wherein the nitrogenous base is ammonia.
12 . The organic tungsten complex according to claim 1 wherein the nitrogenous base is a primary, a secondary, a tertiary or a quaternary amine.
13 . The organic tungsten complex according to claim 10 wherein the nitrogenous base is a diamine according to the formula
wherein n is 1 to 5, and R9 is a hydrocarbon-containing group having at least 6 carbon atoms.
14 . The organic tungsten complex according to claim 10 wherein the nitrogenous base is a polyamine according to the formula
wherein R11 through R15 may be the same or different, and each may be C1 to C25 straight or branched chain alkyl radicals, C1 to C12 alkoxy-(C6 alkylene) radicals, C2 to C12 alkyl amino-(C2 to C6 alkylene) radicals, or sets of R11-R12 and R13-R14 may independently be a cyclic structure; each n can be the same or different ranging from 2 to 6; m is a number from 0 to 10.
15 . The organic tungsten complex according to claim 10 wherein the nitrogenous base is a diamine according to the formula
wherein k is a number from 1 to 10 and R10 is a C1 to C6 hydrocarbon containing group.
16 . The organic tungsten complex according to claim 10 wherein the nitrogenous base is a polyamine according to the formula
wherein R16 and R17 may be the same or different, and may be hydrogen, C1 to C20 alkyl, C3 to C20 alkenyl, C5 to C12 cycloalkyl, or C7 to C15 arylalkyl; and R18 is a hydrogen or a C1 to C20 residue.
17 . The organic tungsten complex according to claim 10 wherein the nitrogenous base is a di- or polyamine according to the formula
wherein X is a hydroxyl or amino group; and R19 is a C8 to C22 alkyl group or a C8 to C22 fatty acid residue
18 . A lubricating composition comprising a major amount of a lubricating oil and about 50 to 50,000 ppm of tungsten provided from an organic tungsten complex, said organic tungsten complex prepared by reacting (a) a tungsten salt, wherein the tungsten salt is the reaction product of an acidic tungsten and a nitrogenous base; and (b) a fatty acid derivative.
19 . The lubricating composition according to claim 18 comprising between about 75 to 2500 ppm of tungsten.
20 . The lubricating composition according to claim 19 comprising between about 250 to 750 ppm of tungsten.
21 . The lubricating composition according to claim 18 further comprising an alkylated diphenylamine and/or an N-alkylated diphenylamine.
22 . The lubricating composition according to claim 18 further comprising a metal dialkyldithiophosphate.
23 . The lubricating composition according to claim 22 wherein the metal dialkyldithiophosphate is zinc dialkyldithiophosphate.
24 . The lubricating composition according to claim 23 wherein the zinc dialkyldithiophosphate is present in an amount of about 0.05 to 5.0 mass percent.
25 . The lubricating composition according to claim 24 wherein the zinc dialkyldithiophosphate is present in an amount of about 0.1 to 1.0 mass percent.
26 . The lubricating composition according to claim 18 further comprising a secondary diarylamine.
27 . The lubricating composition according to claim 21 wherein the alkylated diphenylamine, N-alkylated diphenylamine or secondary diarylamine is present in an amount of about 0.1 to 4.0 mass percent.
28 . The lubricating composition according to claim 27 wherein the alkylated diphenylamine is a polymerized 1,2-dihydro-2,2,4-trimethylquinoline or an alkylated diphenyl aminomethyl benzotriazole or a butylated-octylated diphenylamine.
29 . The lubricating composition according to claim 23 wherein the mass ratio of zinc dialkyldithiophosphate to the organic tungsten complex is about 100:1 to about 1:10.
30 . The lubricating composition according to claim 21 wherein the mass ratio of alkylated diphenylamine to organic tungsten complex is about 75:1 to about 1:3.
31 . The lubricating composition according to claim 18 wherein the composition has a sulfur content of 10 mass percent or less.
32 . The organic tungsten complex according to claim 1 wherein the complex is substantially sulfur-free and substantially phosphorus-free.
33 . The organic tungsten complex according to claim 14 wherein the R11-R12 and R13-R14 cyclic structures are polyisobutylene succinimide.