Lubricant composition
A lubricating composition including an ester; a viscosity index improver; and at least one of a sterically hindered sulfur-containing, phosphorus-containing compound, and its salt.
1 . A lubricating composition comprising:
an ester;
a viscosity index improver; and
at least one of a sulfur-containing, phosphorus-containing compound and a salt of the sulfur-containing, phosphorus-containing compound.
2 . The composition of claim 1 , wherein the ester has a viscosity less than or equal to about 2 cSt at 100° C.
3 . The composition of claim 1 , wherein the ester has the formula RCO 2 R 1 , wherein R comprises an alkyl radical having from about 4 to about 9 carbon atoms and R 1 comprises an alkyl radical having from about 4 to about 15 carbon atoms.
4 . The composition of claim 1 , wherein the ester comprises at least one of isononyl 2-ethylhexanoate, isooctyl 2-ethylhexanoate, 2-ethylhexyl 2-ethylhexanoate, isononyl heptanoate, isononyl isopentanoate, isooctyl heptanoate, isononyl pentanoate, isooctyl isopentanoate, isooctyl pentanoate, octyl pentanoate, nonyl pentanoate, decyl pentanoate, octyl heptanoate, nonyl heptanoate, decyl heptanoate and mixtures thereof.
5 . The composition of claim 1 , wherein the viscosity index improver is a polyalphaolefin.
6 . The composition of claim 5 , wherein the polyalphaolefins has a viscosity of from about 40 to about 1000 cSt at 100° C.
7 . The composition of claim 1 , wherein the sterically hindered sulfur-containing, phosphorus-containing compound is at least one of a compound of formulae (II) and (V):
wherein n is an integer from 1 to 5; and
wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 10 , and R 11 are independently selected from the group consisting of hydrogen, cyano, and hydrocarbyl groups comprising from about 1 to about 30 carbon atoms.
8 . The composition of claim 7 , wherein in formula (II) R 1 and R 2 are methyl and R 3 , R 4 , R 5 , and R 6 are hydrogen.
9 . The composition of claim 1 , wherein the salt of the sulfur-containing, phosphorus-containing compound is at least one of a compound of formulae (III) and (VI):
wherein n is an integer from 1 to 5; and
wherein R 1 , R 2 , R 3 , R 4 , R 6 , R 7 , R 8 , R 9 , R 10 , and R 11 are independently selected from the group consisting of hydrogen, cyano, and hydrocarbyl groups comprising from about 1 to about 30 carbon atoms.
10 . The composition of claim 9 , wherein in formula (III) R 3 , R 4 , R 5 , R 6 , R 7 and R 8 are hydrogen; R 1 and R 2 are methyl; and R 9 is a tertiary C 12-14 alkyl group.
11 . The composition of claim 9 , wherein in formula (VI) R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 are hydrogen; R 9 is a tertiary C 12-14 alkyl group; and R 10 and R 11 are alkyl groups comprising from about 1 to about 6 carbon atoms.
12 . The composition of claim 1 , further comprising a synthetic base oil.
13 . The composition of claim 12 , wherein the synthetic base oil comprises a polyalphaolefins.
14 . The composition of claim 12 , wherein the viscosity index of the combination of the synthetic base oil, the viscosity index improver, and the ester is about 200 or greater.
15 . The composition of claim 1 , further comprising a gas-to-liquid base oil.
16 . The composition of claim 1 , further comprising a boron-containing compound.
17 . The composition of claim 16 , wherein the boron-containing compound is present in the composition in an amount to provide about 5 ppm to about 500 ppm boron.
18 . The composition of claim 16 , wherein the boron-containing compound is a borated nitrogen-containing compound.
19 . The composition of claim 16 , wherein the boron-containing compound is a borated phosphorus-containing compound.
20 . The composition of claim 1 , further comprising an acid and a nitrogen-containing compound, wherein at least one of the acid and the nitrogen-containing compound is a friction modifier.
21 . The composition of claim 20 , wherein the acid is a friction modifier chosen from at least one of an organic carboxylic acid, organic phosphorus acid, organic sulfonic acid, inorganic phosphorus acid, and a mixture thereof.
22 . The composition of claim 21 , wherein the organic phosphorus acid is at least one of dialkyl phosphorus acid, monoalkyl phosphorus acid, dialkyl dithiophosphorus acid, dialkyl thiophosphorus acid, amyl acid phosphate, 2-ethylhexyl acid phosphate, and a mixture thereof.
23 . The composition of claim 20 , wherein the nitrogen-containing compound is a friction modifier and is a mixture of C 8-16 tertiary primary alkyl amine.
24 . A method of lubricating an automotive gear comprising using as the lubricant the composition of claim 1 .
25 . A method of improving antiwear protection in an automotive gear comprising placing a composition according to claim 1 in the automotive gear.
26 . A method of improving fuel efficiency in an automotive gear comprising placing a composition according to claim 1 in an automotive gear.
27 . A method of lubricating an axle comprising using as the lubricant the composition of claim 1 .
28 . A method of improving antiwear protection in an axle comprising placing a composition according to claim 1 in the axle.
29 . A method of improving fuel efficiency in an axle comprising placing a composition according to claim 1 in the axle.
30 . A method of lubricating a stationary gearbox comprising using as the lubricant the composition of claim 1 .
31 . A method of improving antiwear protection in a stationary gearbox comprising placing a composition according to claim 1 in the stationary gearbox.
32 . A method of improving fuel efficiency in a stationary gearbox comprising placing a composition according to claim 1 in the stationary gearbox.
33 . A method of passing ASTM D5704 comprising lubricating a gear with a composition according to claim 1 .
34 . A method of passing ASTM D6121 with lubricated and nonlubricated gear sets comprising lubricating a gear with a composition according to claim 1 .
35 . A method of passing ASTM D6121 with nonlubricated gear sets at least about 325° F. for at least about 16 hours comprising lubricating a gear with a composition according to claim 1 .
36 . A method of maintaining GL-5 and/or SAE J2360 performance comprising lubricating a gear with a composition according to claim 1 .
37 . A lubricating composition comprising an ester; a viscosity index improver; and a reaction product of a sulfur-containing compound, a phosphorus-containing compound, and a nitrogen-containing compound.