Mixed phosphorus esters for lubricant applications
AssigneeThe Lubrizol Corporation
InventorsWilliam D. Abraham, Nga H. Nguyen, Paul E. Adams, Kurt F. Wollenberg
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Abstract
A lubricant composition of an oil of lubricating viscosity and a phosphite ester reaction product of a monomeric phosphorous acid or an ester thereof with a first alkylene diol having two hydroxy groups in a 1,4 or 1,5 or 1,6 relationship and a second, alkyl-substituted, diol being a substituted 1,3-propylene diol, exhibits good wear and frictional performance.
Claims27
A lubricant composition comprising an oil of lubricating viscosity and a phosphite ester composition (A), other than a zinc salt, which comprises the reaction product of
- (a) a monomeric phosphorous acid or an ester thereof with
- (b) at least two alkylene diols:
- a first alkylene diol (i) having two hydroxy groups in a 1,4 or 1,5 or 1,6 relationship;
- a second alkylene diol (ii) being an alkyl-substituted 1,3-propylene diol with one or more of the alkyl substituents thereof being on one or more of the carbon atoms of the propylene unit, the total number of carbon atoms in the alkyl-substituted 1,3-propylene diol being about 5 to about 12;
- wherein the relative molar amounts of monomeric phosphorous acid or ester thereof (a) and the total of the alkylene diols (b) are in a ratio of about 0.9:1.1 to about 1.1:0.9;
- wherein the relative molar amounts of the first alkylene diol (i) and the alkyl-substituted 1,3-propylene diol (ii) are in a ratio of about 30:70 to about 65:35;
- and
- a grease thickener.
A method of lubricating a hydraulic fluid system, a circulating oil system, a turbine system, or an industrial gearbox, comprising supplying thereto a lubricant comprising an oil of lubricating viscosity and a phosphite ester composition (A), other than a zinc salt, which comprises the reaction product of
- (a) a monomeric phosphorous acid or an ester thereof with
- (b) at least two alkylene diols:
- a first alkylene diol (i) having two hydroxy groups in a 1,4 or 1,5 or 1,6 relationship;
- a second alkylene diol (ii) being an alkyl-substituted 1,3-propylene diol with one or more of the alkyl substituents thereof being on one or more of the carbon atoms of the propylene unit, the total number of carbon atoms in the alkyl-substituted 1,3-propylene diol being about 5 to about 12;
- wherein the relative molar amounts of monomeric phosphorous acid or ester thereof (a) and the total of the alkylene diols (b) are in a ratio of about 0.9:1.1 to about 1.1:0.9;
- wherein the relative molar amounts of the first alkylene diol (i) and the alkyl-substituted 1,3-propylene diol (ii) are in a ratio of about 30:70 to about 65:35.
Dependencies are inferred from the claim text.