Lubricating oil composition for hybrid vehicles

Abstract

A lubricating oil composition for hybrid vehicle is described. The composition includes major amount of an oil of lubricating viscosity; hydrocarbyl mono-carboxylic acid or mono-carboxylic acid ester, represented by formula (I) where each R1, R2, R3, R4, R5, and R6 is independently hydrogen or hydrocarbyl group; where one of R5 and R6 is hydrogen; where at least one of R1, R2, R3, and R4 is a hydrocarbyl group; or hydrocarbyl carboxylic acid represented by R-COOH where R is a hydrocarbyl group having at least 3 carbons; and an emulsifier.

Description

[0001] LUBRICATING OIL COMPOSITION FOR HYBRID VEHICLES CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 660,710 filed June 17, 2024, which is hereby incorporated by reference in its entirety. TECHNICAL FIELD

[0002] This disclosure relates to a lubricating oil compositions and methods of using the same. More specifically, the lubricating oil compositions provide rust protection in hybrid vehicles. BACKGROUND

[0003] Modern lubricating oils are formulated to exacting specifications often set by original equipment manufacturers. This often requires blending carefully selected lubricant additives with base oils of lubricating viscosity. The classes or types of lubricant additives found in lubricating oil compositions include, for example, dispersants, detergents, antioxidants, wear inhibitors, rust inhibitors, corrosion inhibitors, foam inhibitors, and / or friction modifiers. The specific application or use (e.g., hybrid vehicles) will typically govern the set of additives that goes into a lubricating oil composition.

[0004] Hybrid vehicles rely on two distinctly different types of motive technologies - internal combustion engine and electric motor. The internal combustion engine mainly drives the vehicle at high speeds. The electric motor drives the vehicle at low speeds and can also assist the internal combustion engine when additional power is needed. It is important for hybrid vehicles to distribute power from the engine and the motor in a well-balanced manner as the vehicle speed increases.

[0005] Moreover, hybrid vehicles typically feature a start-stop system in which the engine stops when the vehicle comes to a stop and the engine fuel system suspends when the vehicle is driven only by motor or braking. This can lead to accumulation of water and fuel in the oil as the engine is not able to sufficiently evaporate the water and fuel, resulting in formation of unstable emulsions which negatively impacts engine performance and leads to corrosion / rust in engine parts.

[0006] The differences between hybrid vehicles and conventional automobile vehicles are significant enough that conventional engine oils are not optimized for use in hybrid vehicles. As a result, lubricating oil compositions designed specifically for hybrid vehicles are needed. More particularly, there is a need for lubricating oil compositions that improve corrosion / rust protection of engine parts in hybrid vehicles. SUMMARY

[0007] In one aspect, there is provided a lubricating oil composition for hybrid vehicle comprising: a) major amount of an oil of lubricating viscosity; b) hydrocarbyl mono- carboxylic acid or mono-carboxylic acid ester, represented by wherein each R1, R2, R3, R4, R5, and R6 is independently hydrogen or hydrocarbyl group; wherein one of R5 and R6 is hydrogen; wherein at least one of R1, R2, R3, and R4 is a hydrocarbyl group; or hydrocarbyl carboxylic acid represented by R-COOH, wherein R is a hydrocarbyl group having at least 3 carbons; and c) an emulsifier.

[0008] In another aspect, there is provided a method of mitigating rust in a hybrid engine, the method comprising: lubricating the engine with a lubricating oil composition comprising: a) major amount of an oil of lubricating viscosity; b) hydrocarbyl mono-carboxylic acid or mono-carboxylic acid ester, represented by wherein each R1, R2, R3, R4, R5, and R6is independently hydrogen or hydrocarbyl group; wherein one of R5and R6is hydrogen; wherein at least one of R1, R2, R3, and R4is a hydrocarbyl group; or hydrocarbyl carboxylic acid represented by R-COOH, wherein R is a hydrocarbyl group having at least 3 carbons; and c) emulsifier. DETAILED DESCRIPTION

[0009] While the disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure as defined by the appended claims.

[0010] To facilitate the understanding of the subject matter disclosed herein, a number of terms, abbreviations or other shorthand as used herein are defined below. Any term, abbreviation or shorthand not defined is understood to have the ordinary meaning used by a skilled artisan contemporaneous with the submission of this application.

[0011] As used herein, the following terms have the following meanings, unless expressly stated to the contrary.

[0012] A “major amount” means in excess of 50 weight % of a composition.

[0013] A “minor amount” means less than 50 weight % of a composition, expressed in respect of the stated additive and in respect of the total mass of all the additives present in the composition, reckoned as active ingredient of the additive or additives.

[0014] “Active ingredients” or “actives” or “oil free” refers to additive material that is not diluent or solvent.

[0015] The present invention provides a lubricating oil composition that is useful for engines (e.g., engines in hybrid vehicles) that are particularly susceptible to corrosion and / or wear. In one embodiment, the present invention provides a lubricating oil composition comprising: (a) a major amount of an oil of lubricating viscosity; (b) a hydrocarbyl carboxylic acid; and (c) an emulsifier. Hydrocarbyl Carboxylic Acid

[0016] The lubricating oil composition of the present invention includes an hydrocarbyl carboxylic acid. Suitable hydrocarbyl carboxylic acids include organic mono-carboxylic acids, and carboxylic acid esters. Organic Mono-carboxylic acids

[0017] In some embodiments, the organic mono-carboxylic acid can be represented by the generalized formula R-COOH wherein R is a hydrocarbyl group having at least 3 carbons, such as at least 4 carbons, at least 5 carbons, at least 6 carbons, at least 7 carbons, at least 8 carbons, at least 9 carbons, at least 10 carbons, at least 11 carbons, at least 12 carbons, at least 13 carbons, at least 14 carbons, or at least 15 carbons. In some embodiments R is a hydrocarbyl group 3 to 50 carbons, such as 3 to 45 carbons, 3 to 40 carbons, 3 to 35 carbons, 3 to 30 carbons, 3 to 25 carbons, 3 to 20 carbons, 4 to 50 carbons, 4 to 45 carbons, 4 to 40 carbons, 4 to 35 carbons, 4 to 30 carbons, 4 to 25 carbons, 4 to 20 carbons, 5 to 50 carbons, 5 to 45 carbons, 5 to 40 carbons, 5 to 35 carbons, 5 to 30 carbons, 5 to 25 carbons, 5 to 20 carbons, 6 to 50 carbons, 6 to 45 carbons, 6 to 40 carbons, 6 to 35 carbons, 6 to 30 carbons, 6 to 25 carbons, 6 to 20 carbons, 7 to 50 carbons, 7 to 45 carbons, 7 to 40 carbons, 7 to 35 carbons, 7 to 30 carbons, 7 to 25 carbons, 7 to 20 carbons, 8 to 50 carbons, 8 to 45 carbons, 8 to 40 carbons, 8 to 35 carbons, 8 to 30 carbons, 8 to 25 carbons, 8 to 20 carbons, 9 to 50 carbons, 9 to 45 carbons, 9 to 40 carbons, 9 to 35 carbons, 9 to 30 carbons, 9 to 25 carbons, 9 to 20 carbons, 10 to 50 carbons, 10 to 45 carbons, 10 to 40 carbons, 10 to 35 carbons, 10 to 30 carbons, 10 to 25 carbons, 10 to 20 carbons, 11 to 50 carbons, 11 to 45 carbons, 11 to 40 carbons, 11 to 35 carbons, 11 to 30 carbons, 11 to 25 carbons, 11 to 20 carbons, 12 to 50 carbons, 12 to 45 carbons, 12 to 40 carbons, 12 to 35 carbons, 12 to 30 carbons, 12 to 25 carbons, 12 to 20 carbons, 13 to 50 carbons, 13 to 45 carbons, 13 to 40 carbons, 13 to 35 carbons, 13 to 30 carbons, 13 to 25 carbons, 13 to 20 carbons, 14 to 50 carbons, 14 to 45 carbons, 14 to 40 carbons, 14 to 35 carbons, 14 to 30 carbons, 14 to 25 carbons, 14 to 20 carbons, 15 to 50 carbons, 15 to 45 carbons, 15 to 40 carbons, 15 to 35 carbons, 15 to 30 carbons, 15 to 25 carbons, or 15 to 20 carbons.

[0018] In some embodiments, R is fully saturated. In some embodiments, R includes a single unsaturated bond. In some embodiments, R includes two unsaturated bonds. In some embodiments, R includes three unsaturated bonds.

[0019] Examples of organic monoacids include saturated fatty acids, unsaturated fatty acids, and polyunsaturated fatty acids. Saturated fatty acids include, for example, butyric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, and the like. Unsaturated fatty acids include, for example oleic acid, palmitoleic acid, and the like. Polyunsaturated fatty acids include linoleic acid, linolenic acid, arachidonic acid, and the like. Organic Acid Esters

[0020] The organic acid ester includes carboxylic acid functional group and ester functional group, wherein the compound is represented by formula (I), Formula I where each R1, R2, R3, and R4is independently a hydrogen or a hydrocarbyl group, R5and R6is independently a hydrogen, a hydrocarbyl group, or a polyalcohol group, wherein one of R5and R6is hydrogen; wherein at least one of R1, R2, R3, and R4is a hydrocarbyl group.

[0021] In some embodiments, the hydrocarbyl group can be an alkyl group or an alkenyl group. Alkyl groups refer to saturated hydrocarbyl groups, which can be linear, branched, cyclic, or a combination of cyclic, linear and / or branched. Alkenyl groups refer to unsaturated hydrocarbyl groups, which can be linear, branched, cyclic, or a combination of cyclic, linear and / or branched.

[0022] In some embodiments, the hydrocarbyl group of R1, R2, R3, or R4is independently a moiety having 1 to 400 carbons, for example, 1 to 380 carbons, 1 to 360 carbons, 1 to 340 carbons, 1 to 320 carbons, 1 to 300 carbons, 1 to 280 carbons, 1 to 260 carbons, 1 to 240 carbons, 1 to 220 carbons, 1 to 200 carbons, 1 to 180 carbons, 1 to 160 carbons, 1 to 140 carbons, 1 to 120 carbons, 1 to 100 carbons, 1 to 80 carbons, 1 to 60 carbons, 1 to 40 carbons, 1 to 30 carbons, 1 to 25 carbons, 1 to 20 carbons, 1 to 15 carbons, 1 to 10 carbons, 2 to 400 carbons, 2 to 380 carbons, 2 to 360 carbons, 2 to 340 carbons, 2 to 320 carbons, 2 to 300 carbons, 2 to 280 carbons, 2 to 260 carbons, 2 to 240 carbons, 2 to 220 carbons, 2 to 200 carbons, 2 to 180 carbons, 2 to 160 carbons, 2 to 140 carbons, 2 to 120 carbons, 2 to 100 carbons, 2 to 80 carbons, 2 to 60 carbons, 2 to 40 carbons, 2 to 30 carbons, 2 to 25 carbons, 2 to 20 carbons, 2 to 15 carbons, 2 to 10 carbons, 3 to 400 carbons, 3 to 380 carbons, 3 to 360 carbons, 3 to 340 carbons, 3 to 320 carbons, 3 to 300 carbons, 3 to 280 carbons, 3 to 260 carbons, 3 to 240 carbons, 3 to 220 carbons, 3 to 200 carbons, 3 to 180 carbons, 3 to 160 carbons, 3 to 140 carbons, 3 to 120 carbons, 3 to 100 carbons, 3 to 80 carbons, 3 to 60 carbons, 3 to 40 carbons, 3 to 30 carbons, 3 to 25 carbons, 3 to 20 carbons, 3 to 15 carbons, 3 to 10 carbons, 4 to 400 carbons, 4 to 380 carbons, 4 to 360 carbons, 4 to 340 carbons, 4 to 320 carbons, 4 to 300 carbons, 4 to 280 carbons, 4 to 260 carbons, 4 to 240 carbons, 4 to 220 carbons, 4 to 200 carbons, 4 to 180 carbons, 4 to 160 carbons, 4 to 140 carbons, 4 to 120 carbons, 4 to 100 carbons, 4 to 80 carbons, 4 to 60 carbons, 4 to 40 carbons, 4 to 30 carbons, 4 to 25 carbons, 4 to 20 carbons, 4 to 15 carbons, 4 to 10 carbons, 5 to 400 carbons, 5 to 380 carbons, 5 to 360 carbons, 5 to 340 carbons, 5 to 320 carbons, 5 to 300 carbons, 5 to 280 carbons, 5 to 260 carbons, 5 to 240 carbons, 5 to 220 carbons, 5 to 200 carbons, 5 to 180 carbons, 5 to 160 carbons, 5 to 140 carbons, 5 to 120 carbons, 5 to 100 carbons, 5 to 80 carbons, 5 to 60 carbons, 5 to 40 carbons, 5 to 30 carbons, 5 to 25 carbons, 5 to 20 carbons, 5 to 15 carbons, 5 to 10 carbons, 6 to 400 carbons, 6 to 380 carbons, 6 to 360 carbons, 6 to 340 carbons, 6 to 320 carbons, 6 to 300 carbons, 6 to 280 carbons, 6 to 260 carbons, 6 to 240 carbons, 6 to 220 carbons, 6 to 200 carbons, 6 to 180 carbons, 6 to 160 carbons, 6 to 140 carbons, 6 to 120 carbons, 6 to 100 carbons, 6 to 80 carbons, 6 to 60 carbons, 6 to 40 carbons, 6 to 30 carbons, 6 to 25 carbons, 6 to 20 carbons, 6 to 15 carbons, 6 to 10 carbons, 7 to 400 carbons, 7 to 380 carbons, 7 to 360 carbons, 7 to 340 carbons, 7 to 320 carbons, 7 to 300 carbons, 7 to 280 carbons, 7 to 260 carbons, 7 to 240 carbons, 7 to 220 carbons, 7 to 200 carbons, 7 to 180 carbons, 7 to 160 carbons, 7 to 140 carbons, 7 to 120 carbons, 7 to 100 carbons, 7 to 80 carbons, 7 to 60 carbons, 7 to 40 carbons, 7 to 30 carbons, 7 to 25 carbons, 7 to 20 carbons, 7 to 15 carbons, 7 to 10 carbons, 8 to 400 carbons, 8 to 380 carbons, 8 to 360 carbons, 8 to 340 carbons, 8 to 320 carbons, 8 to 300 carbons, 8 to 280 carbons, 8 to 260 carbons, 8 to 240 carbons, 8 to 220 carbons, 8 to 200 carbons, 8 to 180 carbons, 8 to 160 carbons, 8 to 140 carbons, 8 to 120 carbons, 8 to 100 carbons, 8 to 80 carbons, 8 to 60 carbons, 8 to 40 carbons, 8 to 30 carbons, 8 to 25 carbons, 8 to 20 carbons, 8 to 15 carbons, 8 to 10 carbons, 9 to 400 carbons, 9 to 380 carbons, 9 to 360 carbons, 9 to 340 carbons, 9 to 320 carbons, 9 to 300 carbons, 9 to 280 carbons, 9 to 260 carbons, 9 to 240 carbons, 9 to 220 carbons, 9 to 200 carbons, 9 to 180 carbons, 9 to 160 carbons, 9 to 140 carbons, 9 to 120 carbons, 9 to 100 carbons, 9 to 80 carbons, 9 to 60 carbons, 9 to 40 carbons, 9 to 30 carbons, 9 to 25 carbons, 9 to 20 carbons, 9 to 15 carbons, 9 to 10 carbons, 10 to 400 carbons, 10 to 380 carbons, 10 to 360 carbons, 10 to 340 carbons, 10 to 320 carbons, 10 to 300 carbons, 10 to 280 carbons, 10 to 260 carbons, 10 to 240 carbons, 10 to 220 carbons, 10 to 200 carbons, 10 to 180 carbons, 10 to 160 carbons, 10 to 140 carbons, 10 to 120 carbons, 10 to 100 carbons, 10 to 80 carbons, 10 to 60 carbons, 10 to 40 carbons, 10 to 30 carbons, 10 to 25 carbons, 10 to 20 carbons, 10 to 15 carbons, 15 to 400 carbons, 15 to 380 carbons, 15 to 360 carbons, 15 to 340 carbons, 15 to 320 carbons, 15 to 300 carbons, 15 to 280 carbons, 15 to 260 carbons, 15 to 240 carbons, 15 to 220 carbons, 15 to 200 carbons, 15 to 180 carbons, 15 to 160 carbons, 15 to 140 carbons, 15 to 120 carbons, 15 to 100 carbons, 15 to 80 carbons, 15 to 60 carbons, 15 to 40 carbons, 15 to 30 carbons, 15 to 25 carbons, 15 to 20 carbons, 20 to 400 carbons, 20 to 380 carbons, 20 to 360 carbons, 20 to 340 carbons, 20 to 320 carbons, 20 to 300 carbons, 20 to 280 carbons, 20 to 260 carbons, 20 to 240 carbons, 20 to 220 carbons, 20 to 200 carbons, 20 to 180 carbons, 20 to 160 carbons, 20 to 140 carbons, 20 to 120 carbons, 20 to 100 carbons, 20 to 80 carbons, 20 to 60 carbons, 20 to 40 carbons, 20 to 30 carbons, 20 to 25 carbons, 50 to 400 carbons, 50 to 380 carbons, 50 to 360 carbons, 50 to 340 carbons, 50 to 320 carbons, 50 to 300 carbons, 50 to 280 carbons, 50 to 260 carbons, 50 to 240 carbons, 50 to 220 carbons, 50 to 200 carbons, 50 to 180 carbons, 50 to 160 carbons, 50 to 140 carbons, 50 to 120 carbons, 50 to 100 carbons, 50 to 80 carbons, 50 to 60 carbons, 100 to 400 carbons, 100 to 380 carbons, 100 to 360 carbons, 100 to 340 carbons, 100 to 320 carbons, 100 to 300 carbons, 100 to 280 carbons, 100 to 260 carbons, 100 to 240 carbons, 100 to 220 carbons, 100 to 200 carbons, 100 to 180 carbons, 100 to 160 carbons, 100 to 140 carbons, 100 to 120 carbons, 200 to 400 carbons, 200 to 380 carbons, 200 to 360 carbons, 200 to 340 carbons, 200 to 320 carbons, 200 to 300 carbons, 200 to 280 carbons, 200 to 260 carbons, 200 to 240 carbons, 200 to 220 carbons, 300 to 400 carbons, 300 to 380 carbons, 300 to 360 carbons, 300 to 340 carbons, or 300 to 320 carbons.

[0023] Suitable examples of R1, R2, R3, or R4include fatty acid moieties (i.e., those derived from fatty acids) and isoaliphatic acid moieties (e.g., those derived from 8- methyloctadecanoic acid). In one embodiment, at least one of R1, R2, R3, and R4is a dodecenyl group. In one embodiment, at least one of R1, R2, R3, and R4is an octadecenyl group. In one embodiment, at least one of R1, R2, R3, and R4is a tetrapropenyl group.

[0024] In some embodiments, the hydrocarbyl group of R5or R6is independently a moiety having 1 to 50 carbon atoms, for example, 1 to 40 carbon atoms, 1 to 30 carbon atoms, 1 to 25 carbon atoms, or 1 to 20 carbon atoms.

[0025] Specific examples of hydrocarbyl di-carboxylic acid include tetrapropenyl succinic acid, pentylsuccinic acid, octylsuccinic acid, ethyl octylsuccinic acid, and the like.

[0026] In general, the hydrocarbyl carboxylic acid, or the acid ester can be present in the lubricating oil composition of the present disclosure in an amount ranging from about 0.05 to about 5.0 wt. %, based on the total weight of the lubricating oil composition, such as about 0.05 to about 4.5 wt.%, about 0.05 to about 4.0 wt.%, about 0.05 to about 3.5 wt.%, about 0.05 to about 3.0 wt.%, about 0.05 to about 2.5 wt.%, about 0.05 to about 2.0 wt.%, about 0.05 to about 1.5 wt.%, about 0.05 to about 1.0 wt.%, about 0.05 to about 0.5 wt.%, about 0.15 to about 4.5 wt.%, about 0.15 to about 4.0 wt.%, about 0.15 to about 3.5 wt.%, about 0.15 to about 3.0 wt.%, about 0.15 to about 2.5 wt.%, about 0.15 to about 2.0 wt.%, about 0.15 to about 1.5 wt.%, about 0.15 to about 1.0 wt.%, about 0.15 to about 0.5 wt.%, about 0.2 to about 5.0 wt.%, about 0.2 to about 4.5 wt.%, about 0.2 to about 4.0 wt.%, about 0.2 to about 3.5 wt.%, about 0.2 to about 3.0 wt.%, about 0.2 to about 2.5 wt.%, about 0.2 to about 2.0 wt.%, about 0.2 to about 1.5 wt.%, about 0.2 to about 1.0 wt.%, about 0.2 to about 0.75 wt.%, about 0.2 to about 0.50 wt.%, about 0.25 to about 5.0 wt.%, about 0.25 to about 4.5 wt.%, about 0.25 to about 4.0 wt.%, about 0.25 to about 3.5 wt.%, about 0.25 to about 3.0 wt.%, about 0.25 to about 2.5 wt.%, about 0.25 to about 2.0 wt.%, about 0.25 to about 1.5 wt.%, about 0.25 to about 1.0 wt.%, about 0.25 to about 0.75 wt.%, or about 0.25 to about 0.50 wt.%. Emulsifiers

[0027] The lubricating oil composition of this disclosure includes emulsifier. Suitable emulsifiers include alkyl ethoxylate and polyalkylene glycol. Alkyl Ethoxylate

[0028] The lubricating oil composition of the present invention includes an alkyl ethoxylate. Suitable alkyl ethoxylates include ethoxylates derived (i.e., reacted with one or more ethylene oxides) from primary, secondary, or tertiary alcohols.

[0029] The alkyl ethoxylate is present in an amount effective to impart a desired degree of rust protection to the lubricating oil composition. In some embodiment, the alkyl ethoxylate is present in about 0.05 to about 5.0 wt. %, based on the total weight of the lubricating oil composition, such as about 0.05 to about 4.5 wt.%, about 0.05 to about 4.0 wt.%, about 0.05 to about 3.5 wt.%, about 0.05 to about 3.0 wt.%, about 0.05 to about 2.5 wt.%, about 0.05 to about 2.0 wt.%, about 0.05 to about 1.5 wt.%, about 0.05 to about 1.0 wt.%, about 0.05 to about 0.5 wt.%, about 0.15 to about 4.5 wt.%, about 0.15 to about 4.0 wt.%, about 0.15 to about 3.5 wt.%, about 0.15 to about 3.0 wt.%, about 0.15 to about 2.5 wt.%, about 0.15 to about 2.0 wt.%, about 0.15 to about 1.5 wt.%, about 0.15 to about 1.0 wt.%, about 0.15 to about 0.5 wt.%, about 0.2 to about 5.0 wt.%, about 0.2 to about 4.5 wt.%, about 0.2 to about 4.0 wt.%, about 0.2 to about 3.5 wt.%, about 0.2 to about 3.0 wt.%, about 0.2 to about 2.5 wt.%, about 0.2 to about 2.0 wt.%, about 0.2 to about 1.5 wt.%, about 0.2 to about 1.0 wt.%, about 0.2 to about 0.75 wt.%, about 0.2 to about 0.50 wt.%, about 0.25 to about 5.0 wt.%, about 0.25 to about 4.5 wt.%, about 0.25 to about 4.0 wt.%, about 0.25 to about 3.5 wt.%, about 0.25 to about 3.0 wt.%, about 0.25 to about 2.5 wt.%, about 0.25 to about 2.0 wt.%, about 0.25 to about 1.5 wt.%, about 0.25 to about 1.0 wt.%, about 0.25 to about 0.75 wt.%, or about 0.25 to about 0.50 wt.%.

[0030] Alkyl ethoxylates of the present disclosure may be represented by the following generalized structure: R7-(O-CH2CH2)x-OH wherein R7is a linear or branched alkyl group having 1 to 50 carbons, and x is an integer between 1 and 6.

[0031] In some embodiments, R7 has 1 to 45 carbons, 1 to 40 carbons, 1 to 35 carbons, 1 to 30 carbon, 1 to 25 carbons, 1 to 20 carbons, 1 to 15 carbons, 2 to 50 carbons, 2 to 45 carbons, 2 to 40 carbons, 2 to 35 carbons, 2 to 30 carbons, 2 to 25 carbons, 2 to 20 carbons, 2 to 15 carbons, 3 to 50 carbons, 3 to 45 carbons, 3 to 40 carbons, 3 to 35 carbons, 3 to 30 carbons, 3 to 25 carbons, 3 to 20 carbons, 3 to 15 carbons, 4 to 50 carbons, 4 to 45 carbons, 4 to 40 carbons, 4 to 35 carbons, 4 to 30 carbons, 4 to 25 carbons, 4 to 20 carbons, 4 to 15 carbons, 5 to 50 carbons, 5 to 45 carbons, 5 to 40 carbons, 5 to 35 carbons, 5 to 30 carbons, 5 to 25 carbons, 5 to 20 carbons, 5 to 15 carbons, 6 to 50 carbons, 6 to 45 carbons, 6 to 40 carbons, 6 to 35 carbons, 6 to 30 carbons, 6 to 25 carbons, 6 to 20 carbons, 6 to 15 carbons, 7 to 50 carbons, 7 to 45 carbons, 7 to 40 carbons, 7 to 35 carbons, 7 to 30 carbons, 7 to 25 carbons, 7 to 20 carbons, 7 to 15 carbons, 8 to 50 carbons, 8 to 45 carbons, 8 to 40 carbons, 8 to 35 carbons, 8 to 30 carbons, 8 to 25 carbons, 8 to 20 carbons, 8 to 15 carbons, 9 to 50 carbons, 9 to 45 carbons, 9 to 40 carbons, 9 to 35 carbons, 9 to 30 carbons, 9 to 25 carbons, 9 to 20 carbons, 9 to 15 carbons, 10 to 50 carbons, 10 to 45 carbons, 10 to 40 carbons, 10 to 35 carbons, 10 to 30 carbons, 10 to 25 carbons, 10 to 20 carbons, or 10 to 15 carbons.

[0032] Specific examples of alkyl ethoxylates include, but are not limited, to the following structures: Polyalkylene glycol

[0033] The lubricating oil composition of the present invention includes a poly alkylene glycol (e.g., polypropylene glycol). According to an embodiment, poly alkylene glycol can act as an emulsifier and is represented by formula (II) Formula II wherein R7, R8, and R9are each independently a hydrogen radical or hydrocarbyl radical and n is from 5 to 1000, such as from 5 to 500, 7 to 500, 5 to 100, 5 to 75, 7 to 100, 7 to 75, and so forth. In some embodiments, n is from 7 to 900, 20 to 800, 50 to 750, 75 to 500, 100 to 400 or 200 to 300.

[0034] In some embodiments, the polyalkylene glycol has a molecular weight (MW) of about 400 g / mol to about 4000 g / mol such as from about 500 g / mol to 3500 g / mol, 750 g / mol to 3000 g / mol, 1000 g / mol to 2500 g / mol, 1250 g / mol to 2250 g / mol, 1500 g / mol to 2500 g / mol and so forth.

[0035] The polyalkylene glycol may be present in an amount ranging from about 0.05 to about 5.0 wt. %, based on the total weight of the lubricating oil composition, such as about 0.05 to about 4.5 wt.%, about 0.05 to about 4.0 wt.%, about 0.05 to about 3.5 wt.%, about 0.05 to about 3.0 wt.%, about 0.05 to about 2.5 wt.%, about 0.05 to about 2.0 wt.%, about 0.05 to about 1.5 wt.%, about 0.05 to about 1.0 wt.%, about 0.05 to about 0.5 wt.%, about 0.15 to about 4.5 wt.%, about 0.15 to about 4.0 wt.%, about 0.15 to about 3.5 wt.%, about 0.15 to about 3.0 wt.%, about 0.15 to about 2.5 wt.%, about 0.15 to about 2.0 wt.%, about 0.15 to about 1.5 wt.%, about 0.15 to about 1.0 wt.%, about 0.15 to about 0.5 wt.%, about 0.2 to about 5.0 wt.%, about 0.2 to about 4.5 wt.%, about 0.2 to about 4.0 wt.%, about 0.2 to about 3.5 wt.%, about 0.2 to about 3.0 wt.%, about 0.2 to about 2.5 wt.%, about 0.2 to about 2.0 wt.%, about 0.2 to about 1.5 wt.%, about 0.2 to about 1.0 wt.%, about 0.2 to about 0.75 wt.%, about 0.2 to about 0.50 wt.%, about 0.25 to about 5.0 wt.%, about 0.25 to about 4.5 wt.%, about 0.25 to about 4.0 wt.%, about 0.25 to about 3.5 wt.%, about 0.25 to about 3.0 wt.%, about 0.25 to about 2.5 wt.%, about 0.25 to about 2.0 wt.%, about 0.25 to about 1.5 wt.%, about 0.25 to about 1.0 wt.%, about 0.25 to about 0.75 wt.%, or about 0.25 to about 0.50 wt.%. Lubricating Oil Compositions

[0036] The oil of lubricating viscosity (sometimes referred to as “base stock” or “base oil”) is the primary liquid constituent of a lubricant, into which additives and possibly other oils are blended, for example to produce a final lubricant (or lubricant composition). A base oil, which is useful for making concentrates as well as for making lubricating oil compositions therefrom, may be selected from natural (vegetable, animal or mineral) and synthetic lubricating oils and mixtures thereof.

[0037] Definitions for the base stocks and base oils in this disclosure are the same as those found in American Petroleum Institute (API) Publication 1509 Annex E (“API Base Oil Interchangeability Guidelines for Passenger Car Motor Oils and Diesel Engine Oils,” December 2016). Group I base stocks contain less than 90% saturates and / or greater than 0.03% sulfur and have a viscosity index greater than or equal to 80 and less than 120 using the test methods specified in Table E-1. Group II base stocks contain greater than or equal to 90% saturates and less than or equal to 0.03% sulfur and have a viscosity index greater than or equal to 80 and less than 120 using the test methods specified in Table E-1. Group III base stocks contain greater than or equal to 90% saturates and less than or equal to 0.03% sulfur and have a viscosity index greater than or equal to 120 using the test methods specified in Table E-1. Group IV base stocks are polyalphaolefins (PAO). Group V base stocks include all other base stocks not included in Group I, II, III, or IV.

[0038] Natural oils include animal oils, vegetable oils (e.g., castor oil and lard oil), and mineral oils. Animal and vegetable oils possessing favorable thermal oxidative stability can be used. Of the natural oils, mineral oils are preferred. Mineral oils vary widely as to their crude source, for example, as to whether they are paraffinic, naphthenic, or mixed paraffinic- naphthenic. Oils derived from coal or shale are also useful. Natural oils vary also as to the method used for their production and purification, for example, their distillation range and whether they are straight run or cracked, hydrorefined, or solvent extracted.

[0039] Synthetic oils include hydrocarbon oil. Hydrocarbon oils include oils such as polymerized and interpolymerized olefins (e.g., polybutylenes, polypropylenes, propylene isobutylene copolymers, ethylene-olefin copolymers, and ethylene-alphaolefin copolymers). Polyalphaolefin (PAO) oil base stocks are commonly used synthetic hydrocarbon oil. By way of example, PAOs derived from C8 to C14 olefins, e.g., C8, C10, C12, C14 olefins or mixtures thereof, may be utilized.

[0040] Other useful fluids for use as base oils include non-conventional or unconventional base stocks that have been processed, preferably catalytically, or synthesized to provide high performance characteristics.

[0041] In some embodiments, the base oil may be a renewable or bio-derived engine oil. Examples of such engine oils are disclosed in WO2016061050 and US20190338211, which is incorporated herein by reference. According to some embodiments, the renewable or bio-derived base oil includes a biobased hydrocarbon, such as an isoparaffinic hydrocarbon derived from hydrocarbon terpenes, such as myrcene, ocimene, and farnesene. In some embodiments, the biobased hydrocarbon is produced from fatty acids or fatty esters.

[0042] Non-conventional or unconventional base stocks / base oils include one or more of a mixture of base stock(s) derived from one or more Gas-to-Liquids (GTL) materials, as well as isomerate / isodewaxate base stock(s) derived from natural wax or waxy feeds, mineral and or non-mineral oil waxy feed stocks such as slack waxes, natural waxes, and waxy stocks such as gas oils, waxy fuels hydrocracker bottoms, waxy raffinate, hydrocrackate, thermal crackates, or other mineral, mineral oil, or even non-petroleum oil derived waxy materials such as waxy materials received from coal liquefaction or shale oil, and mixtures of such base stocks.

[0043] Base oils for use in the lubricating oil compositions of present disclosure are any of the variety of oils corresponding to API Group I, Group II, Group III, Group IV, and Group V oils, and mixtures thereof, preferably API Group II, Group III, Group IV, and Group V oils, and mixtures thereof, more preferably the Group III to Group V base oils due to their exceptional volatility, stability, viscometric and cleanliness features.

[0044] Typically, the base oil will have a kinematic viscosity at 100oC (ASTM D445) in a range of 2.5 to 20 mm2 / s (e.g., 3 to 12 mm2 / s, 4 to 10 mm2 / s, or 4.5 to 8 mm2 / s). Lubricant Additives

[0045] The lubricating oil compositions of the present disclosure may also contain other conventional additives that can impart a desirable property to or improve the lubricating oil composition in which these additives are dispersed or dissolved. Any additive known to a person of ordinary skill in the art may be used in the lubricating oil compositions disclosed herein. Some suitable additives have been described in Mortier et al., “Chemistry and Technology of Lubricants”, 2nd Edition, London, Springer, (1996); and Leslie R. Rudnick, “Lubricant Additives: Chemistry and Applications”, New York, Marcel Dekker (2003), both of which are incorporated herein by reference. For example, the lubricating oil compositions can be blended with antioxidants (e.g., alkylated diphenylamine, phenolic antioxidants), anti- wear agents, detergents such as metal detergents, rust inhibitors, dehazing agents, demulsifying agents, metal deactivating agents, friction modifiers (e.g., ester-based friction modifier), viscosity modifiers (e.g., olefin copolymer), pour point depressants, antifoaming agents (e.g., silicon-based foam inhibitors), co-solvents, corrosion-inhibitors, dispersants, multifunctional agents, dyes, extreme pressure agents and the like and mixtures thereof. A variety of the additives are known and commercially available. These additives, or their analogous compounds, can be employed for the preparation of the lubricating oil compositions of the disclosure by the usual blending procedures.

[0046] In the preparation of lubricating oil formulations, it is common practice to introduce the additives in the form of 10 to 100 wt. % active ingredient concentrates in hydrocarbon oil, e.g. mineral lubricating oil, or other suitable solvent.

[0047] Usually, these concentrates may be diluted with 3 to 100, e.g., 5 to 40, parts by weight of lubricating oil per part by weight of the additive package in forming finished lubricants, e.g. crankcase motor oils. The purpose of concentrates, of course, is to make the handling of the various materials less difficult and awkward as well as to facilitate solution or dispersion in the final blend.

[0048] Each of the foregoing additives, when used, is used at a functionally effective amount to impart the desired properties to the lubricant. Thus, for example, if an additive is a friction modifier, a functionally effective amount of this friction modifier would be an amount sufficient to impart the desired friction modifying characteristics to the lubricant.

[0049] In general, the concentration of each of the additives in the lubricating oil composition, when used, may range from about 0.001 wt. % to about 20 wt. %, from about 0.01 wt. % to about 15 wt. %, or from about 0.1 wt. % to about 10 wt. %, from about 0.005 wt.% to about 5 wt.%, or from about 0.1 wt.% to about 2.5 wt.%, based on the total weight of the lubricating oil composition. Further, the total amount of the additives in the lubricating oil composition may range from about 0.001 wt.% to about 20 wt.%, from about 0.01 wt.% to about 10 wt.%, or from about 0.1 wt.% to about 5 wt.%, based on the total weight of the lubricating oil composition.

[0050] The following examples are presented to exemplify embodiments of the disclosure but are not intended to limit the disclosure to the specific embodiments set forth. Unless indicated to the contrary, all parts and percentages are by weight. All numerical values are approximate. When numerical ranges are given, it should be understood that embodiments outside the stated ranges may still fall within the scope of the disclosure. Specific details described in each example should not be construed as necessary features of the disclosure.

[0051] It will be understood that various modifications may be made to the embodiments disclosed herein. Therefore, the above description should not be construed as limiting, but merely as exemplifications of preferred embodiments. For example, the functions described above and implemented as the best mode for operating the present disclosure are for illustration purposes only. Other arrangements and methods may be implemented by those skilled in the art without departing from the scope and spirit of this disclosure. Moreover, those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto. EXAMPLES

[0052] The following lubricating oil examples are intended for illustrative purposes only and do not limit in any way the scope of the present disclosure.

[0053] The lubricating oils were evaluated by the Japanese Industrial Standard (JIS) K2246 test that has been slightly modified for hybrid vehicle lubricants. JIS K2246 test involves coating test piece sample with test oil and checking for rusting on the test sample. In the modified JIS K2246 test, the test piece sample is coated with a mixture containing test oil and distilled water. Table 2 summarizes the JIS K2246 test results.

[0054] The test piece sample is placed in a humidity cabinet above 95% relative humidity (RH) at 49°C and allowed to stand for 72 hours. The test assesses the ability of oils to prevent rust on metal materials or metal products, mainly consisting of iron and steel. The ASTM D1748 test (Humidity cabinet rust test) is run in a similar fashion. A lower rust rating indicates better anti-corrosion performance. A rating of 10 or lower indicates a pass rating.

[0055] The mixture containing test oil and distilled water was prepared according to the following steps: 1. Mix 30 ml of distilled water with 270 ml of test oil in a plastic container. 2. Transfer the mixture of test oil and distilled water to a 500 ml container. 3. Stir the mixture containing the test oil and distilled water on the day of the JIS K2246 test followed by 30 seconds handshaking. 4. Heat the test oil in a convection oven at 70 ºC for 30 min. 5. After 30 minutes, remove the test oil from oven and allow the test oil to cool down to room temperature. 6. Just prior to soaking the test sample in the test oil, handshake the test oil again for 30 seconds. 7. Start the JIS K2246 test. Baseline Formulation

[0056] Table 1 below summarizes the lubricating oil samples (inventive examples 1 and 2 and comparative examples 3, 4, 5, 6, and 7) that were tested. Table 1 1. Tetrapropenyl succinic acid mono ester of 1,2-propane diol 2. Oleic acid 3. Tetrapropenyl succinic acid 4. Glycerol mono-oleate 5. Ethoxylated secondary alcohols, C11-15, EO3 6. Polyoxyetheylene dodecylphenyl ether 7. Polypropylene glycol Mw=2000 8. Average of 3 runs (lower is better)

[0057] In all cases the baseline formulation is that of a GF-6 capable lubricating oil. Examples 1 and 2 show excellent results in the rust performance test demonstrating synergistic effect of combining carboxylic acid and alkyl ethoxylate.

[0058] Referencing Comparative Example 1, when the alkyl ethoxylate is replaced with an aryl ethoxylate, there is a dramatic decrease in performance (compared against Example 2).

[0059] When the alkyl ethoxylate is replaced with polypropylene glycol (Comparative Example 3), sharp decrease in performance is also observed.

[0060] When an alkyl carboxylic acid (oleic acid) is esterified to form a carboxylate ester (Comparative Example 5), there is a dramatic decrease in performance particularly when compared against Example 2.

[0061] When alkyl ethoxylate is omitted as in Comparative Example 6, no rust performance benefit is observed.

[0062] Similarly, when only alkyl ethoxylate is in the formulation (Comparative Example 7), there is no improvement in the rust performance.

[0063] All documents described herein are incorporated by reference herein, including any priority documents and / or testing procedures to the extent they are not inconsistent with this text. As is apparent from the foregoing general description and the specific embodiments, while forms of the present disclosure have been illustrated and described, various modifications can be made without departing from the spirit and scope of the present disclosure. Accordingly, it is not intended that the present disclosure be limited thereby.

[0064] For the sake of brevity, only certain ranges are explicitly disclosed herein. However, ranges from any lower limit may be combined with any upper limit to recite a range not explicitly recited, as well as, ranges from any lower limit may be combined with any other lower limit to recite a range not explicitly recited, in the same way, ranges from any upper limit may be combined with any other upper limit to recite a range not explicitly recited. Additionally, within a range includes every point or individual value between its end points even though not explicitly recited. Thus, every point or individual value may serve as its own lower or upper limit combined with any other point or individual value or any other lower or upper limit, to recite a range not explicitly recited.

[0065] Likewise, the term “comprising” is considered synonymous with the term “including.” Likewise, whenever a composition, an element or a group of elements is preceded with the transitional phrase “comprising,” it is understood that we also contemplate the same composition or group of elements with transitional phrases “consisting essentially of,” “consisting of,” “selected from the group of consisting of,” or “is” preceding the recitation of the composition, element, or elements and vice versa.

[0066] The terms "a" and "the" as used herein are understood to encompass the plural as well as the singular.

[0067] Various terms have been defined above. To the extent a term used in a claim is not defined above, it should be given the broadest definition persons in the pertinent art have given that term as reflected in at least one printed publication or issued patent. Furthermore, all patents, test procedures, and other documents cited in this application are fully incorporated by reference to the extent such disclosure is not inconsistent with this application and for all jurisdictions in which such incorporation is permitted.

[0068] The foregoing description of the disclosure illustrates and describes the present disclosure. Additionally, the disclosure shows and describes only the preferred embodiments but, as mentioned above, it is to be understood that the disclosure is capable of use in various other combinations, modifications, and environments and is capable of changes or modifications within the scope of the concept as expressed herein, commensurate with the above teachings and / or the skill or knowledge of the relevant art. While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

[0069] It is understood that when combinations, subsets, groups, etc. of elements are disclosed (e.g., combinations of components in a composition, or combinations of steps in a method), that while specific reference of each of the various individual and collective combinations and permutations of these elements may not be explicitly disclosed, each is specifically contemplated and described herein.

[0070] The embodiments described hereinabove are further intended to explain best modes known of practicing it and to enable others skilled in the art to utilize the disclosure in such, or other, embodiments and with the various modifications required by the particular applications or uses. Accordingly, the description is not intended to limit it to the form disclosed herein. Also, it is intended that the appended claims be construed to include alternative embodiments.

Claims

CLAIMS 1. A lubricating oil composition for hybrid vehicle comprising: a) major amount of an oil of lubricating viscosity; b) hydrocarbyl mono-carboxylic acid or mono-carboxylic acid ester, represented bywherein each R1, R2, R3, R4, R5, and R6is independently hydrogen or hydrocarbyl group; wherein one of R5and R6is hydrogen; wherein at least one of R1, R2, R3, and R4is a hydrocarbyl group; or hydrocarbyl carboxylic acid represented by R-COOH wherein R is a hydrocarbyl group having at least 3 carbons; and c) an emulsifier.

2. The lubricating oil composition of claim 1, wherein the hydrocarbyl carboxylic acid is a succinic acid.

3. The lubricating oil composition of claim 1, wherein the hydrocarbyl carboxylic acid is a saturated or unsaturated fatty acid.

4. The lubricating oil composition of claim 1, wherein the hydrocarbyl carboxylic acid or acid ester is present in about 0.05 to 5.0 wt.% based on the total lubricating oil composition.

5. The lubricating oil composition of claim 1, wherein the emulsifier is an alkyl ethoxylate or a polyalkylene glycol.

6. The lubricating oil composition of claim 5, wherein the alkyl ethoxylate is derived from primary, secondary, or tertiary alcohol.

7. The lubricating oil composition of claim 5, wherein the alkyl ethoxylate is represented by the structure, R7-(O-CH2CH2)x-OH, wherein R7is a linear or branched alkyl group having 1 to 50 carbons, and x is an integer between 1 and 6.

8. The lubricating oil composition of claim 5, wherein the emulsifier is present in about 0.05 to about 5.0 wt.%.

9. The lubricating oil composition of claim 5, wherein the polyalkylene glycol is polypropylene glycol.

10. A method of mitigating rust in a hybrid engine, the method comprising: lubricating the engine with a lubricating oil composition comprising: a) major amount of an oil of lubricating viscosity; b) hydrocarbyl mono-carboxylic acid or mono-carboxylic acid ester, represented bywherein each R1, R2, R3, R4, R5, and R6is independently hydrogen or hydrocarbyl group; wherein one of R5and R6is hydrogen; wherein at least one of R1, R2, R3, and R4is a hydrocarbyl group; or hydrocarbyl carboxylic acid represented by R-COOH wherein R is a hydrocarbyl group having at least 3 carbons; and c) emulsifier.

11. The method of claim 10, wherein the hydrocarbyl carboxylic acid is a succinic acid.

12. The method of claim 10, wherein the hydrocarbyl carboxylic acid is a saturated or unsaturated fatty acid.

13. The method of claim 10, wherein the hydrocarbyl carboxylic acid or acid ester is present in about 0.05 to 5.0 wt.% based on the total lubricating oil composition.

14. The method of claim 10, wherein the emulsifier is alkyl ethoxylate or polyalkylene glycol.

15. The method of claim 14, wherein the alkyl ethoxylate is derived from primary, secondary, or tertiary alcohol.

16. The method of claim 14, wherein the alkyl ethoxylate is represented by the structure, R7-(O-CH2CH2)x-OH, wherein R7is a linear or branched alkyl group having 1 to 50 carbons, and x is an integer between 1 and 6.

17. The method of claim 10, wherein the emulsifier is present in about 0.05 to about 5.0 wt.%.

18. The method of claim 14, wherein the polyalkylene glycol is polypropylene glycol.

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