Disclosed are compositions containing at least one of the following: (1) estolide polyethylene glycol diesters; (2) hydroxy derived estolide polyethylene glycol diesters; (3) unsaturated hydroxy derived estolide polyethylene glycol diesters; (4) estolide trimetholpropane diesters; (5) hydroxy derived estolide trimetholpropane diesters; (6) unsaturated hydroxy derived estolide trimetholpropane diesters; (7) estolide epoxide polyethylene glycol diesters; (8) estolide dihydroxide polyethylene glycol diesters; (9) mono-capped hydroxy derived estolide epoxide polyethylene glycol diesters; (10) mono-capped hydroxy derived estolide dihydroxide polyethylene glycol diesters;
and mixtures thereof; and optionally a carrier. All the compounds can be used as a viscosity index improver thereby improving a lubricant's performance.

This invention relates to the use of a metallic or non-metallic detergent which is a hydrocarbyl-substituted salicylic acid or a derivative thereof in a non-aqueous lubricant composition as an inhibitor of lead corrosion associated with ashless, organic ester, anti-wear additives and/or friction modifiers.

A lubricant composition is provided which comprises a base oil and hydroxytyrosol and/or esters thereof. Also provided is a lubricant composition in which the esters have a solubility in the base oil at 25 C. of at least 0.1 g/l. Further provided is a lubricant composition in which the esters are at least partly carboxylic acid esters comprising esters of hydroxytyrosol and C.sub.2-10 carboxylic acids.

A liquid anti-friction composition includes an ester product having a number average molecular weight that is greater than 3800 g/mol, and obtained by subjecting a mixture that includes diglycerol, a monobasic acid component, and a dibasic acid component to an esterification reaction. The monobasic acid component includes at least one C.sub.14-C.sub.24 branched chain fatty acid.

The present invention relates to a lubricated system comprising: a) a component comprising a first surface which is a diamond-like carbon (DLC) surface; b) a component comprising a second surface; and c) a lubricant formulation interposed between the first surface and second surface. The lubricant formulation comprises: i) a base stock; ii) a molybdenum compound; iii) an organic polymer comprising a hydrophobic polymeric sub unit selected from polyesters and functionalised polyolefins and a hydrophilic polymeric sub unit selected from polyethers; and iv) optionally, other additives. The combination of the molybdenum compound and the organic polymer in the lubricant formulation reduces the wear on one or more of the surfaces in the lubricated system when compared with using the molybdenum containing friction modifier alone.

A lubricant base oil composed of an ester. The ester includes a component (A) derived from trimethylolpropane in a molar percentage A.sub.mol % of 25 to 42 mol %; components (B) derived from monovalent straight-chain saturated fatty acids each having a carbon number of 8 to 12 in a molar percentage B.sub.mol % of 33 to 55 mol %: and a component (C) derived from adipic acid in a molar ratio C.sub.mol % of 12 to 34 mol %. The components (B) include lauric acid in a molar percentage of 5 to 50 mol %, and (B.sub.COOH+C.sub.COOH)/A.sub.OH is 0.90 to 1.02. A.sub.OH represents a hydroxyl equivalent of the component (A), B.sub.COOH represents a carboxyl group equivalent of the components (B); and C.sub.COOH represents a carboxyl group equivalent of the component (C).

A base oil includes an ester compound obtained by reacting a fatty acid component and a monohydric alcohol component. The fatty acid component includes a C.sub.4-C.sub.28 fatty acid. The monohydric alcohol component includes at least one C.sub.4-C.sub.22 straight chain monohydric alcohol and at least one C.sub.4-C.sub.22 branched chain monohydric alcohol. A lubricant oil composition including the base oil is also disclosed.

Ester compounds, such as for use in a lubricant, are based on di-, tri- or higher functional carboxylic acids according to formula (I)

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Levulinic-capped estolides having improved physical properties that make them more desirable and suitable as bio-based industrial or commercial products are disclosed. The physical properties of the disclosed estolide compositions have surprisingly low pour points that are substantially lower than previously known estolide compounds and superior to petroleum-based compounds designed for similar applications.

Improved organic anti-wear additive compositions are disclosed containing certain citric acid esters, e.g., mixtures comprising citrate oligomers, and fatty acid alkanolamides. The combination exhibits excellent and synergistic anti-wear activity in lubricants. The compositions of the invention beneficially allow one to reduce amounts of zinc and phosphorus that are often used in lubricants, while boosting anti-wear performance and maintaining, and often enhancing, friction reduction properties.