Methods of reducing lead corrosion in an internal combustion engine
The present disclosure describes lubricant compositions effective to reduce lead corrosion through an admixture of lubricant additives including at least a base oil of lubricating viscosity, a dispersant, a friction modifier, and boron-containing compound.
1 . A method of reducing lead corrosion in an internal combustion engine lubricated with a lubricating oil composition, the method comprising supplying to the internal combustion engine a lubricating oil composition including a hydrocarbyl substituted succinimide dispersant obtained from a hydrocarbyl substituted acylating agent reacted with a nitrogen source, a nitrogen-free organic friction modifier having carboxylic acid and/or hydroxyl groups, and a major amount of a base oil or a blend of base oils of lubricating viscosity;
wherein the lubricating oil composition includes an admixture of a boron-containing compound selected from boric acid or boronic acid, the hydrocarbyl substituted succinimide dispersant, and the nitrogen-free organic friction modifier;
wherein the boron-containing compound has the structure X—B—(OH) 2 wherein X is a hydroxyl group, a linear or branched alkyl group, a cyclic hydrocarbyl group, one or more aromatic groups, a benzofuranyl group, a dibenzofuranyl group, or combinations thereof; and
wherein the method reduces lead corrosion in the internal combustion engine as compared to a method including a lubricating oil composition with reaction products of the boron-containing compound.
2 . The method of reducing lead corrosion in an internal combustion engine of claim 1 , wherein the nitrogen-free organic friction modifier has pendant hydroxyl groups obtained from a fatty acid reacted with an alkanol.
3 . The method of reducing lead corrosion in an internal combustion engine of claim 2 , wherein the lubricating oil composition includes about 250 ppm to about 350 ppm of boron provided by the boron-containing compound per each 1 weight percent of the nitrogen-free organic friction modifier.
4 . The method of reducing lead corrosion in an internal combustion engine of claim 3 , wherein the lubricating oil composition exhibits no more than about 500 ppm of lead corrosion per each 1 weight percent of the nitrogen-free organic friction modifier as measured by ASTM D6594.
5 . The method of reducing lead corrosion in an internal combustion engine of claim 1 , wherein the hydrocarbyl substituted succinimide dispersant is boronated from a source of boron separate from the boron-containing compound.
6 . The method of reducing lead corrosion in an internal combustion engine of claim 1 , wherein the boron-containing compound is a boronic acid with X being a linear or branched C1 to C10 group, one or more aromatic groups, a benzofuranyl group, a dibenzofuranyl group, or combinations thereof.
7 . The method of reducing lead corrosion in an internal combustion engine of claim 1 , wherein the nitrogen-free organic friction modifier includes a blend of mono- and di-esters of fatty acids.
8 . The method of reducing lead corrosion in an internal combustion engine of claim 7 , wherein the nitrogen-free organic friction modifier includes a blend of mono- and di-esters of oleic acid.
9 . The method of reducing lead corrosion in an internal combustion engine of claim 8 , wherein the nitrogen-free organic friction modifier includes glycerol monooleate.
10 . The method of reducing lead corrosion in an internal combustion engine of claim 4 , wherein the lubricating oil composition includes about 100 ppm to about 300 ppm of boron provided by the boron-containing compound, up to about 10 weight percent of the hydrocarbyl substituted succinimide dispersant, and up to about 1 weight percent of the nitrogen-free organic friction modifier.
11 . A lubricating oil composition for reducing lead corrosion in an internal combustion engine, the lubricating oil composition comprising:
an admixture of a hydrocarbyl substituted succinimide dispersant, a nitrogen-free organic friction modifier, and a boron-containing compound;
the hydrocarbyl substituted succinimide dispersant obtained from a hydrocarbyl substituted acylating agent reacted with a nitrogen source;
the nitrogen-free organic friction modifier having carboxylic acid and/or hydroxyl groups;
the boron-containing compound selected from boric acid or boronic acid, wherein the boron-containing compound has the structure X—B—(OH) 2 wherein X is a hydroxyl group, a linear or branched alkyl group, a cyclic hydrocarbyl group, one or more aromatic groups, a benzofuranyl group, a dibenzofuranyl group, or combinations thereof;
a major amount of a base oil or blend of base oils of lubricating viscosity; and
wherein the lubricating composition has a lead corrosion lower than a lead corrosion of a lubricating composition including reaction products of the boron-containing compound.
12 . The lubricating oil composition for reducing lead corrosion of claim 11 , wherein the nitrogen-free organic friction modifier has pendant hydroxyl groups obtained from a fatty acid reacted with an alkanol.
13 . The lubricating oil composition for reducing lead corrosion of claim 12 , wherein the lubricating oil composition includes about 250 ppm to about 350 ppm of boron provided by the boron-containing compound per each 1 weight percent of the nitrogen-free organic friction modifier.
14 . The lubricating oil composition for reducing lead corrosion of claim 13 , wherein the lubricating oil composition exhibits no more than about 500 ppm of lead corrosion per each 1 weight percent of the nitrogen-free organic friction modifier as measured by ASTM D6594.
15 . The lubricating oil composition for reducing lead corrosion of claim 11 , wherein the hydrocarbyl substituted succinimide dispersant is boronated from a source of boron separate from the boron-containing compound.
16 . The lubricating oil composition for reducing lead corrosion of claim 11 , wherein the boron-containing compound is a boronic acid with X being a linear or branched C1 to C10 group, one or more aromatic groups, a benzofuranyl group, a dibenzofuranyl group, or combinations thereof.
17 . The lubricating oil composition for reducing lead corrosion of claim 11 , wherein the nitrogen-free organic friction modifier includes a blend of mono- and di-esters of fatty acids.
18 . The lubricating oil composition for reducing lead corrosion of claim 17 , wherein the nitrogen-free organic friction modifier includes a blend of mono- and di-esters of oleic acid.
19 . The lubricating oil composition for reducing lead corrosion of claim 18 , wherein the nitrogen-free organic friction modifier includes glycerol monooleate.
20 . The lubricating oil composition for reducing lead corrosion of claim 14 , wherein the lubricating oil composition includes about 100 to about 300 ppm of boron provided from the boron-containing compound, up to about 10 weight percent of the hydrocarbyl substituted succinimide dispersant, and up to about 1 weight percent of the nitrogen-free organic friction modifier.
21 . The lubricating oil composition for reducing lead corrosion of claim 11 , wherein the lubricating oil composition is a passenger car motor oil.
22 . The method of reducing lead corrosion in an internal combustion engine of claim 1 , wherein the boron-containing compound is selected from boric acid, 2-methylpropyl boronic acid, phenyl boric acid, naphthalene-1-boronic acid, or combinations thereof.
23 . The lubricating oil composition for reducing lead corrosion of claim 11 , wherein the boron-containing compound is selected from boric acid, 2-methylpropyl boronic acid, phenyl boric acid, naphthalene-1-boronic acid, or combinations thereof.
24 . The method of reducing lead corrosion in an internal combustion engine of claim 1 , wherein the lubricating oil composition includes about 100 ppm to about 300 ppm of boron provided by the boron-containing compound, up to about 10 weight percent of the hydrocarbyl substituted succinimide dispersant, and up to about 1 weight percent of the nitrogen-free organic friction modifier;
wherein the nitrogen-free organic friction modifier includes glycerol monooleate; and
wherein the boron-containing compound is selected from boric acid, 2-methylpropyl boronic acid, phenyl boric acid, naphthalene-1-boronic acid, or combinations thereof.
25 . The method of reducing lead corrosion in an internal combustion engine of claim 24 , wherein the lubricating oil composition includes about 130 ppm to about 180 ppm of boron provided by the boron-compound and about 280 ppm to about 320 ppm of boron provided by the boron-containing compound per each 1 weight percent of the nitrogen-free organic friction modifier.
26 . The lubricating oil composition for reducing lead corrosion of claim 11 , wherein the lubricating oil composition includes about 100 ppm to about 300 ppm of boron provided by the boron-containing compound, up to about 10 weight percent of the hydrocarbyl substituted succinimide dispersant, and up to about 1 weight percent of the nitrogen-free organic friction modifier;
wherein the nitrogen-free organic friction modifier includes glycerol monooleate; and
wherein the boron-containing compound is selected from boric acid, 2-methylpropyl boronic acid, phenyl boric acid, naphthalene-1-boronic acid, or combinations thereof.
27 . The lubricating oil composition for reducing lead corrosion of claim 26 , wherein the lubricating oil composition includes about 130 ppm to about 180 ppm of boron provided by the boron-compound and about 280 ppm to about 320 ppm of boron provided by the boron-containing compound per each 1 weight percent of the nitrogen-free organic friction modifier.