ENGINE LUBRICANT

Description

FIELD OF THE DISCLOSURE

This application generally relates to lubricant compositions and methods related thereto.

BACKGROUND

Conventional engine lubricants generally contain, among other things, an oil base stock, an antiwear additive to reduce wear between engine parts, a detergent to help maintain engine cleanliness, a dispersant to suspend contaminants in the oil, and an antioxidant, though various blends and formulations may vary depending on application.

The American Petroleum Institute (API) defines Group I oil basestocks as solvent-refined mineral oils; Group I oil basestocks contain the least saturates and highest amount of sulfur and generally have the lowest viscosity indices. Group I generally defines the bottom tier of lubricant performance. Group II and Group III oil basestocks are high viscosity index and very high viscosity index basestocks, respectively. The Group III oil basestocks generally contain fewer unsaturates and sulfur than the Group II oils. Group IV oil basestocks consist of polyalphaolefins, which are produced via the catalytic oligomerization of linear alphaolefins (LAOs). Group V includes all the other oil basestocks not included in Groups I through IV; Group V basestocks include lubricants based on or derived from esters.

Engine oils including various API graded basestocks may be formulated and selected for various uses depending on application needs. Viscosity performance may be used among other factors to select an engine oil. Higher viscosity engine oils such as SAE xW-40 and xW-50 grades are widely used, in particular in heavy duty applications where additional wear, contaminants, harsh temperatures (e.g., below −15° C.), or other factors are present.

SUMMARY OF THE DISCLOSURE

Various details of the present disclosure are hereinafter summarized to provide a basic understanding. This summary is not an exhaustive overview of the disclosure and is neither intended to identify certain elements of the disclosure, nor to delineate the scope thereof. Rather, the primary purpose of this summary is to present some concepts of the disclosure in a simplified form prior to the more detailed description that is presented hereinafter.

According to an embodiment consistent with the present disclosure, lubricant compositions comprise: about 40 mass % to about 60 mass % of a first oil base stock, wherein the first oil basestock is an API group I basestock or API group II basestock; about 20 mass % to about 45 mass % of a second oil basestock, wherein the second oil basestock comprises an API group II extra heavy basestock, and wherein the API group II extra heavy basestock has: a kinematic viscosity (ASTM D445, 40° C.) of 320 cSt to 520 cSt, a kinematic viscosity (ASTM D445, 100° C.) of 22 cSt to 36 cSt, a viscosity index (ASTM D2270) of 80 to 119, a pour point (ASTM D97) of −6° C. or less, and a saturate content (ASTM D7419) of 90 mass % or greater.

In another embodiment consistent with the present disclosure, methods comprise: operating an engine with an engine oil, the engine oil comprising: about 40 mass % to about 60 mass % of a first oil base stock, wherein the first oil basestock is an API group I basestock or API group II basestock; about 20 mass % to about 45 mass % of a second oil basestock, wherein the second oil basestock comprises an API group II extra heavy basestock, and wherein the API group II extra heavy basestock has: a kinematic viscosity (ASTM D445, 40° C.) of 320 cSt to 520 cSt, a kinematic viscosity (ASTM D445, 100° C.) of 22 cSt to 36 cSt, a viscosity index (ASTM D2270) of 80 to 119, a pour point (ASTM D97) of −6° C. or less, and a saturate content (ASTM D7419) of 90 mass % or greater.

Any combinations of the various embodiments and implementations disclosed herein can be used in a further embodiment, consistent with the disclosure. These and other features and attributes of the disclosed compositions and methods of the present disclosure and their advantageous applications and/or uses will be apparent from the detailed description which follows.

BRIEF DESCRIPTION OF THE DRAWINGS

Not applicable.

DETAILED DESCRIPTION

This application generally relates to lubricant compositions and methods related thereto.

The term “mass %” as used herein indicates percentage by mass such as percentage by weight (e.g., wt %), “vol %” as used herein indicates percentage by volume, “mol %” as used herein indicates percentage by mole, “ppm” as used herein indicates parts per million, and “ppm wt” and “wppm” are used interchangeably and mean parts per million on a weight basis. All concentrations herein, unless otherwise stated, are expressed on the basis of the total amount of the composition in question.

The term “polymer” as used herein refers to any two or more of the same or different repeating units/mer units or units. The term “homopolymer” as used herein refers to a polymer having units that are the same. The term “copolymer” as used herein refers to a polymer having two or more units that are different from each other and includes terpolymers and the like. The term “terpolymer” as used herein refers to a polymer having three units that are different from each other. The term “different” as used herein as it refers to units indicates that the units differ from each other by at least one atom or are different isomerically. Likewise, the definition of polymer, as used herein, includes homopolymers, copolymers, and the like.

The term “alphaolefin” refers to any linear or branched compound of carbon and hydrogen having at least one double bond between the a and R carbon atoms. For purposes of this specification and the claims appended thereto, when a polymer or copolymer is referred to as including an alpha-olefin (e.g., a polyalphaolefin) the alpha-olefin present in such polymer or copolymer is the polymerized form of the alpha-olefin.

The term “oil base stock” as used herein refers to any base fluid that could be used in a lubricant including, but not limited to, a terpene, a mineral oil, a synthetic hydrocarbon, an ester, the like, or any combination thereof. An oil base stock as used herein may include Group I, II, III, IV, and V (as defined by American Petroleum Institute [API]) base oils, including any combination thereof. The terms “base oil”, “oil base stock”, “oil basestock,” “basestock oil,” “base stock oil,” simply “basestock,” or any grammatical variations thereof are used interchangeably herein.

According to the American Petroleum Institute (API) classifications, base stocks are categorized in five groups based on their saturated hydrocarbon content (saturates) (quoted as a weight percent (wt %)), sulfur level (wt %), and viscosity index (see Table 1 below). Lubricant base stocks are typically produced in large-scale from petroleum sources. Group I, II, and III base stocks are derived from crude oil via processing, such as solvent extraction, hydroprocessing, solvent or catalytic dewaxing, and hydroisomerization. Group III base stocks also can be produced from synthetic hydrocarbon liquids obtained from natural gas, coal or other fossil resources; Group IV base stocks, the polyalphaolefins (PAO), are produced by oligomerization of alpha olefins, such as 1-decene; Group V base stocks include everything that does not belong to Groups I-IV, such as naphthenics, polyalkylene glycols (PAG), and esters.

TABLE 1
API Basestock Group Classifications.

	API	mass %	mass %	Viscosity
	Classification	Saturates	Sulfur	Index (VI)
	Group I	<90 and/or	>0.03 and	≥80 and <120
	Group II	≥90 and	≤0.03 and	≥80 and <120
	Group III	≥90 and	≤0.03 and	≥120

	Group IV	Polyalphaolefins (PAO)
	Group V	All others not in Groups I, II, III, or IV

It should be noted that as used in lubricant compositions of the present disclosure, Group I and/or Group II base stocks may have at least one property that is enhanced relative to a minimum Group I and/or Group II specification, respectively.

Lubricating base oils, including API Group I and/or API Group II basestocks, of the present disclosure may be derived from any suitable source. Basestock oils useful in the present disclosure may include natural oils, synthetic oils, and/or unconventional oils (or mixtures thereof). Basestock oils suitable for the present disclosure may be used unrefined, refined, or rerefined (the latter is also known as reclaimed or reprocessed oil). Unrefined oils are those obtained directly from a natural or synthetic source and used without added purification and may include shale oil obtained directly from retorting operations, petroleum oil obtained directly from primary distillation, and ester oil obtained directly from an esterification process. Refined oils are similar to the oils discussed for unrefined oils except refined oils are subjected to one or more purification steps to improve at least one lubricating oil property. One skilled in the art will be familiar with many purification processes. Such purification processes may include solvent extraction, secondary distillation, acid extraction, base extraction, filtration, percolation, and the like. Rerefined oils may be obtained by processes analogous to refined oils but using an oil that has been previously used as a feed stock. API Group I and/or API Group II base stocks of the present disclosure may be processed in any suitable manner described herein including being solvent refined and/or hydrotreated.

Lubricant compositions and methods of the present disclosure may enable increased performance when used as an engine oil. Lubricant compositions of the present disclosure may enable reduced use of viscosity modifiers and/or lessened use of API group I high viscosity bright stock through the addition of API group II extra heavy basestock oil in combination with other components. Lubricant compositions of the present disclosure may have generally similar or enhanced cold temperature and viscosity properties compared to conventional lubricant compositions, while maintaining generally higher performance. Such higher performance of lubricant compositions of the present disclosure may include reduced shearing of the oil, reduced volatility of the oil, reduced oxidation of the oil, and reduced deposit formulation.

Lubricant compositions of the present disclosure may have various properties that meet or exceed various industry standards, including SAE xW-40 and xW-50 (e.g., SAE 20W-50). Lubricant compositions of the present disclosure may have a kinematic viscosity (ASTM D445, 100° C.) of 10 cSt to 30 cSt, or 12.5 cSt to 26.1 cSt, or 12.5 cSt to 16.3 cSt, or 16.3 cSt to 21.9 cSt. Lubricant compositions of the present disclosure may have a pour point (ASTM D97) of −9° C. or less, or −21° C. or less, or −9° C. to −69° C., or −21° C. to −63° C. Lubricant compositions of the present disclosure may have a NOACK Volatility (ASTM D5800) of 18 weight (mass %) or less, or 5 mass % to 15 mass %, or 7.5 mass % to 12 mass %. Lubricant compositions of the present disclosure may have a Cold-Cranking Simulator test result (ASTM D5293) of 10,000 cP or less, or 1,000 cP to 13,000 cP, or 1,000 cP to 9,500 cP, or 9,500 cP or less, or 1,000 cP to 7,000 cP, or 7,000 cP or less at the appropriate SAE J300 viscosity grades. Lubricant compositions of the present disclosure may have a Viscometer Yield Strength (ASTM D4684) of 35 Pa or less. Lubricant compositions of the present disclosure may have an Apparent Viscosity (ASTM D4684) of 60,000 cP or less, or 1,000 cP to 60,000 cP, or 10,000 cP to 60,000 cP at the appropriate SAE J300 viscosity grade.

Lubricant compositions of the present disclosure may have enhanced performance in several key lubricant areas. These areas may include, but are not limited to, shear stability, oxidation control, deposit control, and aged oil low temperature. Appropriate test methods for shear stability performance may include, but are not limited to, ASTM D7109, ASTM D6278, and ASTM D2603. Appropriate test methods for oxidation control may include, but are not limited to, CEC L-109-16, Daimler Truck methods for oxidation with and without B100 (available at ISP Salzbergen GmbH & Co. KG or APL Automobil-Prüftechnik Landau GmbH). Appropriate test methods for deposit control may include, but are not limited to, ASTM D6335, ASTM D7097, DIN 51535, JPI-5S-55-99, and FTM3462. Appropriate test methods for aged oil low temperature properties may include, but are not limited to, CEC L-105-12 and ASTM D7528.

The present disclosure includes methods and compositions relating to lubricants comprising a first oil basestock comprising an API group I basestock and/or an API group II basestock group, and additionally comprising a second oil basestock comprising an API group II basestock. Lubricant compositions of the present disclosure may include from about 10 mass % to about 80 mass %, or about 40 mass % to about 60 mass %, or about 42 mass % to about 58 mass %, or about 48 mass %, or about 44 mass %, or about 54 mass %, or about 56 mass % of a first oil basestock and from about 10 mass % to about 80 mass %, or about 20 mass % to about 45 mass %, or about 23 mass % to about 40 mass % or about, or about 35 mass %, or about 40 mass %, or about 23 mass %, or about 28 mass % of a second oil basestock.

Group I base stocks used within the first oil basestock of the present disclosure may have a kinematic viscosity (ASTM 445, 40° C.) of 5 cSt to 95 cSt, or 15 cSt to 80 cSt, or 27 cSt to about 32 cSt, or 29 cSt to 32 cSt. Group I base stocks used within the first oil basestock of the present disclosure may have a pour point (ASTM D97) of −9° C. or less, or −9º° C. to −20° C., or −9° C. to −15° C., or −12° C. or less.

Group II base stocks used within the first oil basestock of the present disclosure may have a kinematic viscosity (ASTM 445, 100° C.) of 5 cSt to 10 cSt, or 4 cSt to 8 cSt, or 4 cSt to 6 cSt, or 5 cSt to 6 cSt. Group II base stocks used within the first oil basestock of the present disclosure may have a pour point (ASTM D97) of −10° C. or less, or −15° C. to −20° C., or −15° C. to −18° C., or −16° C. or less.

It should be noted that first oil basestocks may comprise substantially no API group I high viscosity bright stock. “Group I high viscosity bright stock,” or any grammatical variations thereof as used herein refers to an API group I basestock oil with a kinematic viscosity (ASTM D445, 100° C.) greater than 20 cSt, or greater than 25 cSt, or from 30 cSt to 33 cSt. “Substantially no,” and grammatical variations thereof as used herein refer to a compound having less than about 1 mass %, or about 0.001 mass % to about 1 mass %, or about 0 mass % to about 1 mass % of a specified compound.

The second oil basestock may include suitable API group II basestocks such as group II extra heavy basestocks. Group II extra heavy basestocks of interest in the present disclosure, may have a kinematic viscosity (ASTM D445, 40° C.) of 300 cSt to 600 cSt (or 320 cSt to 520 cSt, or 380 cSt to 520 cSt, or 450 cSt to 520 cSt) and a kinematic viscosity (ASTM D445-21, 100° C.) of 22 cSt to 40 cSt (or 22 cSt to 36 cSt, or 27 cSt to 36 cSt, or 32 cSt to 36 cSt). Suitable Group II extra heavy basestocks may have a viscosity index (ASTM D2270) of 80 to 119 (or 95 to 115). Suitable Group II extra heavy basestocks may have a pour point (IP 15 or ASTM D97) of −35° C. to −6° C. (or −35° C. to −15° C., or −6° C. or less, or −15° C. or less). Suitable Group II extra heavy basestocks may have a saturate content (ASTM D7419) of 90 mass % or greater (or 90 mass % to 99.99 mass %, or 95 mass % to 99.99 mass %, or 98 mass % to 99.99 mass %, or 90 mass % to 99 mass %, or 95 mass % to 99 mass %, or 98 mass % to 99 mass %, or 95 mass % or greater, or 98 mass % or greater, or 99 mass % or greater). Other characteristics of suitable Group II extra heavy basestocks may include, but are not limited to: basestock color (ASTM D6045) of L1.5 to L0.5 (or L1.5 to L1.0, or L1.0 to L0.5); carbon residue (ASTM D4530) of 0.0001 mass % to 0.1 mass %, or 0.001 mass % to 0.01 mass %, or 0 mass % to 0.1 mass %, or 0 mass % to 0.01 mass %, or 0.1 mass % or less, or 0.01 mass % or less; cloud point (ASTM D2500) of −60° C. to −2° C., or −60° C. to −30° C., or −30° C. to −2° C., or −2° C. or less, or −30° C. or less, or −60° C. or less; flashpoint (ASTM D92) of 250° C. and 300° C., or 250° C. to 275° C., 275° C. to 300° C., or 250° C. or greater. Preferred Group II extra heavy basestocks for use as a second oil basestock may include those commercially available under the tradenames EHC™ (including, but not limited to, EHC 340 MAX™) (ExxonMobil Corporation).

Viscosity Modifier

One or more viscosity modifiers (also known as “Viscosity Index Improvers”, “VI improvers,” and “viscosity improvers”) may be included in lubricant compositions of the present disclosure. Viscosity modifiers can increase the viscosity of a lubricant. In some cases, viscosity modifiers can serve to provide lubricants with high and low temperature operability. These additives impart shear stability at elevated temperatures and acceptable viscosity at low temperatures. The viscosity modifier can be present in lubricant compositions in an amount from about 1.0 mass % to about 30.0 mass %, or about 1.0 mass % to about 20.0 mass %, or about 5.0 mass % to about 15.0 mass %, or about 8.0 to about 12.0 mass %, or about 10.0 mass %, or about 5.0 mass %, based on the total mass of a lubricant composition. Preferred lubricant compositions may include less than about 5.0 mass %, or about 0.1 mass % to about 5 mass % viscosity modifier.

Suitable viscosity modifiers include high molecular weight hydrocarbons, polyesters, and viscosity modifier dispersants that function as both a viscosity index improver and a dispersant. Typical molecular weights of these polymers are between about 10,000 to 1,500,000, more typically about 20,000 to about 1,200,000, and even more typically about 50,000 to about 1,000,000. The typical molecular weight for polymethacrylate or polyacrylate viscosity modifiers is less than about 50,000.

Examples of suitable viscosity modifiers are linear or star-shaped polymers and copolymers of methacrylate, isobutylene, butadiene, olefins, or alkylated styrenes. Preferred viscosity modifiers may include polyisobutylene. Another suitable viscosity modifier is polymethacrylate (e.g., copolymers of various chain length alkyl methacrylates), some formulations of which also serve as pour point depressants. Other suitable viscosity modifiers include, but are not limited to, copolymers of ethylene and propylene, hydrogenated block copolymers of styrene and isoprene, and polyacrylates (copolymers of various chain length acrylates, for example). Specific examples include, but are not limited to, styrene-isoprene or styrene-butadiene based polymers having a molecular weight of about 50,000 to 200,000.

Suitable olefin copolymers include, but are not limited to, those commercially available from: Chevron Oronite under the tradename PARATONE® (such as PARATONE® 24EX, PARATONE® 8900E and PARATONE® 8941); Afton Chemical Corporation under the tradename HITEC® (such as HITEC® 5850B); and The Lubrizol Corporation under the tradename LUBRIZOL® 7067C. Hydrogenated polyisoprene star polymers may include, but are not limited to, those commercially available from Infineum International under the tradename SV200 and SV600. Hydrogenated diene-styrene block copolymers may include, but are not limited to, those commercially available from Infineum International, e.g., under the tradename SV 50.

Dispersant

Lubricant compositions of the present disclosure can also include one or more dispersants. During engine operation, oil-insoluble oxidation byproducts can be produced. Dispersants can help keep these byproducts in solution, thus diminishing their deposition on metal surfaces. Dispersants used in the formulation of lubricant compositions can be ashless or ash-forming in nature. Preferably, dispersants included herein may be ashless, meaning that such dispersants are organic materials that forms substantially no ash upon combustion. For example, non-metal-containing or borated metal-free dispersants are considered ashless. In contrast, metal-containing detergents discussed above form ash upon combustion.

Such dispersants can be present in lubricant compositions in an amount of about 0.1 mass % to about 20.0 mass %, preferably about 0.5 mass % to about 8.0 mass %, or more preferably about 0.5 mass % to 4.0 mass %, based on a total weight of lubricant compositions. The hydrocarbon numbers of the dispersant atoms can range from C60 to C1000, or from C70 to C300, or from C70 to C200. These dispersants may contain both neutral and basic nitrogen or mixtures of both. The dispersants can be end-capped by borates and/or cyclic carbonates.

Suitable dispersants can contain a polar group attached to a relatively high molecular weight hydrocarbon chain. The polar group typically contains at least one element of nitrogen, oxygen, or phosphorus. Typical hydrocarbon chains contain 50 to 400 carbon atoms.

A particularly useful class of dispersants are the alkenylsuccinic derivatives, typically produced by the reaction of a long chain hydrocarbyl substituted succinic compound, usually a hydrocarbyl substituted succinic anhydride, with a polyhydroxy or polyamino compound. The long chain hydrocarbyl group constituting the oleophilic portion of the molecule which confers solubility in the oil is normally a polyisobutylene group. Many examples of this type of dispersant are well known commercially and in the literature. See, for example, U.S. Pat. Nos. 3,172,892; 3,215,707; 3,219,666; 3,316, 177; 3,341,542; 3,444,170; 3,454,607; 3,541,012; 3,630,904; 3,632,511; 3,787,374; and 4,234,435. Other types of dispersant are described in U.S. Pat. Nos. 3,036,003; 3,200,107; 3,254,025; 3,275,554; 3,438,757; 3,454,555; 3,565,804; 3,413,347; 3,697,574; 3,725,277; 3,725,480; 3,726,882; 4,454,059; 3,329,658; 3,449,250; 3,519,565; 3,666,730; 3,687,849; 3,702,300; 4,100,082; and 5,705,458. A further description of dispersants can be found, for example, in U.S. Pat. No. 5,366,648.

Hydrocarbyl-substituted succinic acid and hydrocarbyl-substituted succinic anhydride derivatives also can be used as dispersants. In particular, succinimide, succinate esters, or succinate ester amides prepared by the reaction of a hydrocarbon-substituted succinic acid compound, preferably having at least 50 carbon atoms in the hydrocarbon substituent, with at least one equivalent of an alkylene amine, are particularly useful. On occasion, having a hydrocarbon substituent having 20 to 50 carbon atoms can be useful.

Succinimides can be formed by the condensation reaction between hydrocarbyl substituted succinic anhydrides and amines. Molar ratios can vary depending on the polyamine. For example, the molar ratio of hydrocarbyl substituted succinic anhydride to TEPA can vary from 1:1 to 5:1. Representative examples are shown in U.S. Pat. Nos. 3,087,936; 3,172,892; 3,219,666; 3,272,746; 3,322,670; 3,652,616; and 3,948,800; and in Canada Patent No. 1,094,044.

Succinate esters can be formed by the condensation reaction between hydrocarbyl substituted succinic anhydrides and alcohols or polyols. Molar ratios can vary depending on the alcohol or polyol used. For example, the condensation product of a hydrocarbyl substituted succinic anhydride and pentaerythritol is a useful dispersant.

Succinate ester amides can be formed by a condensation reaction between hydrocarbyl substituted succinic anhydrides and alkanol amines. Suitable alkanol amines include ethoxylated polyalkylpolyamines, propoxylated polyalkylpolyamines, and polyalkenylpolyamines such as polyethylene polyamines. One example is propoxylated hexamethylenediamine. Representative examples are shown in U.S. Pat. No. 4,426,305.

The molecular weight of the hydrocarbyl substituted succinic anhydrides typically ranges between 800 and 2,500 or more. The above products can be post-reacted with various reagents such as sulfur, oxygen, formaldehyde, and carboxylic acids such as oleic acid. The above products can also be post-reacted with boron compounds such as boric acid, borate esters, and highly borated dispersants, to form borated dispersants generally having from 0.1 to 5.0 moles of boron per mole of dispersant reaction product.

Mannich based dispersants can also be used and are made from the reaction of alkylphenols, formaldehyde, and amines. See U.S. Pat. No. 4,767,551, which is incorporated herein by reference. Process aids and catalysts, such as oleic acid and sulfonic acids, can also be part of the reaction mixture. Molecular weights of the alkylphenols can range from 800 to 2,500. Representative examples are shown in U.S. Pat. Nos. 3,697,574; 3,703,536; 3,704,308; 3,751,365; 3,756,953; 3,798,165; and 3,803,039.

Typical high molecular weight aliphatic acid modified Mannich condensation products can be prepared from high molecular weight alkyl-substituted hydroxyaromatics or HNR₂ group-containing reactants.

Hydrocarbyl substituted amine ashless dispersant additives are well known to those skilled in the art. See, for example, U.S. Pat. Nos. 3,275,554; 3,438,757; 3,565,804; 3,755,433; 3,822,209; and 5,084,197.

Preferred dispersants may include borated and non-borated succinimides, including those derivatives from mono-succinimides, bis-succinimides, and/or mixtures of mono- and bis-succinimides, wherein the hydrocarbyl succinimide is derived from a hydrocarbylene group such as polyisobutylene having a Mn of from 500 to 5,000, or from 1,000 to 3,000, or from 1,000 to 2,000, or a mixture of such hydrocarbylene groups, often with high terminal vinylic groups. Other preferred dispersants may include succinic acid-esters and amides, alkylphenol-polyamine-coupled Mannich adducts, their capped derivatives, and other related components.

Polymethacrylate or polyacrylate derivatives are another class of dispersants. These dispersants are typically prepared by reacting a nitrogen-containing monomer and a methacrylic or acrylic acid ester containing 5 to 25 carbon atoms in the ester group. Representative examples are shown in U.S. Pat. Nos. 2,100,993 and 6,323,164. Polymethacrylate and polyacrylate dispersants are normally used as multifunctional viscosity index improvers. The lower molecular weight versions can be used as lubricant dispersants or fuel detergents.

The use of polymethacrylate or polyacrylate dispersants are preferred in polar esters of a non-aromatic dicarboxylic acid, preferably adipate esters, since many other conventional dispersants are less soluble. The preferred dispersants for polyol esters include polymethacrylate and polyacrylate dispersants.

Inhibitors and Antirust Additives

Antirust additives (or corrosion inhibitors) are additives that protect lubricated metal surfaces against chemical attack by water or other contaminants. A wide variety of such additives/inhibitors are commercially available.

One type of antirust additive is a polar compound that wets the metal surface preferentially, protecting it with a film of oil. Another type of antirust additive absorbs water by incorporating it in a water-in-oil emulsion so that only the oil touches the metal surface. Yet another type of antirust additive chemically adheres to the metal to produce a non-reactive surface. Examples of suitable antirust additives may include, but are not limited to, zinc dithiophosphates, metal phenolates, basic metal sulfonates, fatty acids, amines, the like, or any combination thereof. Such antirust additives may be used in an amount of about 0.01 mass % to about 10 mass %, or about 0.01 mass % to about 5 mass %, or about 0.01 mass % to about 2 mass %.

Pour Point Depressant (PPD)

Pour point depressants (also known as lube oil flow improvers) may be included in lubricant compositions of the present disclosure. Such pour point depressant may be added to lubricant compositions of the present disclosure to lower the minimum temperature at which the fluid will flow or can be poured. Examples of suitable pour point depressants may include, but are not limited to, polymethacrylates, polyacrylates, polyarylamides, condensation products of haloparaffin waxes and aromatic compounds, vinyl carboxylate polymers, and terpolymers of dialkylfumarates, vinyl esters of fatty acids, allyl vinyl ethers, the like, or any combination thereof. U.S. Pat. Nos. 1,815,022; 2,015,748; 2,191,498; 2,387,501; 2,655,479; 2,666,746; 2,721,877; 2,721,878; and 3,250,715 describe useful pour point depressants and/or the preparation thereof. Such pour point depressants may be used in an amount of about 0.01 mass % to about 10.0 mass % percent, or preferably about 0.01 mass % to about 5 mass %. Preferred lubricant compositions of the present disclosure may include about 1 mass % or less, or about 0.01 mass % to about 1.0 mass % pour point depressant.

Other Additives

Lubricant compositions of the present disclosure may additionally include other lubricant performance additives known in the art such as antioxidants, detergents, metal deactivators, extreme pressure additives, anti-seizure agents, wax modifiers, fluid-loss additives, seal compatibility agents, friction modifiers, lubricity agents, anti-staining agents, chromophoric agents, defoamers, demulsifiers, emulsifiers, densifiers, wetting agents, gelling agents, tackiness agents, colorants, and others. These additives are commonly delivered with varying amounts of diluent oil that may, for example, range from about 5 mass % to about 50 mass %. When lubricant compositions include one or more of the foregoing additives, the additive(s) may be blended into a “concentrate,” a “premix,” or a “slurry” to allow further use when blending a fully formulated lubricant.

Methods

The present disclosure may further include methods comprising operating an engine with an engine oil, the engine oil comprising lubricant compositions as described herein. The engine oil may provide lubrication to various moving parts of the engine. Said engine may comprise any suitable engine including preferably an internal combustion engine (e.g., an intermittent combustion engine (e.g., a piston engine, the like) or a continuous combustion engine (e.g., a gas turbine, a jet engine, the like)).

Additional Embodiments

To facilitate a better understanding of the embodiments of the present invention, the following examples of preferred or representative embodiments are given. In no way should the following examples be read to limit, or to define, the scope of the invention.

Embodiments disclosed herein include:

A. Lubricant compositions. The lubricant compositions comprise: about 40 mass % to about 60 mass % of a first oil base stock, wherein the first oil basestock is an API group I basestock or API group II basestock; about 20 mass % to about 45 mass % of a second oil basestock, wherein the second oil basestock comprises an API group II extra heavy basestock, and wherein the API group II extra heavy basestock has: a kinematic viscosity (ASTM D445, 40° C.) of 320 cSt to 520 cSt, a kinematic viscosity (ASTM D445, 100° C.) of 22 cSt to 36 cSt, a viscosity index (ASTM D2270) of 80 to 119, a pour point (ASTM D97) of −6° C. or less, and a saturate content (ASTM D7419) of 90 mass % or greater.

B. Lubricant methods. The methods comprise: operating an engine with an engine oil, the engine oil comprising: about 40 mass % to about 60 mass % of a first oil base stock, wherein the first oil basestock is an API group I basestock or API group II basestock; about 20 mass % to about 45 mass % of a second oil basestock, wherein the second oil basestock comprises an API group II extra heavy basestock, and wherein the API group II extra heavy basestock has: a kinematic viscosity (ASTM D445, 40° C.) of 320 cSt to 520 cSt, a kinematic viscosity (ASTM D445, 100° C.) of 22 cSt to 36 cSt, a viscosity index (ASTM D2270) of 80 to 119, a pour point (ASTM D97) of −6° C. or less, and a saturate content (ASTM D7419) of 90 mass % or greater.

Each of Embodiments A or B may have one or more of the following additional elements in any combination.

Element 1: wherein the first oil comprises substantially no group I high viscosity bright stock.

Element 2: wherein the first oil comprises less than 1 mass % of API group I high viscosity bright stock.

Element 3: wherein the first oil basestock comprises an API group I basestock, and wherein the API group I basestock has: a kinematic viscosity (ASTM 445, 40° C.) of 15 cSt to 80 cSt, and a pour point (ASTM D97) of −9° C. or less.

Element 4: wherein the first oil basestock comprises an API group II basestock, and wherein the API group II basestock has: a kinematic viscosity (ASTM 445, 100° C.) of 5 cSt to 10 cSt, and a pour point (ASTM D97) of −10° C. or less.

Element 5: wherein the lubricant composition a kinematic viscosity (ASTM D445, 100° C.) of 12.5 cSt to 26.1 cSt.

Element 6: wherein the lubricant composition has a pour point (ASTM D97) of −21° C. or less.

Element 7: wherein the lubricant composition has a NOACK Volatility (ASTM D5800) of 18 mass % or less.

Element 8: wherein the lubricant composition has a NOACK Volatility (ASTM D5800) from 5 mass % to 15 mass %.

Element 9: wherein the lubricant composition has a Cold-Cranking Simulator test result (ASTM D5293, −15° C.) of 10,000 cP or less.

Element 10: wherein the lubricant composition has a Viscometer Yield Strength (ASTM D4684, −25° C.) of 35 Pa or less.

Element 11: wherein the lubricant composition has an Apparent Viscosity (ASTM D4684, −25° C.) of 60,000 cP or less.

Element 12: wherein the lubricant composition comprises about 5 mass % or less viscosity modifier.

Element 13: wherein the lubricant composition meets or exceeds standards for SAE 20W-50.

Element 14: wherein the API group II extra heavy basestock has: a kinematic viscosity (ASTM D445, 40° C.) of 460 cSt to 520 cSt, a kinematic viscosity (ASTM D445, 100° C.) of 32 cSt to 36 cSt, a viscosity index (ASTM D2270) of 80 to 119, a pour point (ASTM D97) of −15° C. or less, and a saturate content (ASTM D7419) of 98 mass % or greater.

Exemplary combinations applicable to A and B include, but are not limited to, 1&2, 1&3, 1&4; 1&5; 1&6; 1&7; 1&8; 1&9; 1&10; 1&11; 1&12; 1&13; 1&14; 2&3; 2&4; 2&5; 2&6; 2&7; 2&8; 2&9; 2&10; 2&11; 2&12; 2&13; 2&14; 3&4; 3&5; 3&6; 3&7; 3&8; 3&9; 3&10; 3&11; 3&12; 3&13; 3&14; 4&5; 4&6; 4&7; 4&8; 4&9; 4&10; 4&11; 4&12; 4&13; 4&14; 1-3; 1-4; 1-5; 1-6; 1-7; 1-8; 1-9; 1-10; 1-11; 1-12; 1-13; 1-14; 2-4; 2-5; 2-6; 2-7; 2-8; 2-9; 2-10; 2-11; 2-12; 2-13; 2-14; 3-5; 3-6; 3-7; 3-8; 3-9; 3-10; 3-11; 3-12; 3-13; 3-14; 4-6; 4-7; 4-8; 4-9; 4-10; 4-11; 4-12; 4-13; 4-14; 5&6, 5-7; 5-8; 5-9; 5-10; 5-11; 5-12; 5-13; 5-14; 6-14; 7-14; 8-14; 9-14; 10-14; 11-14; 12-14; 13-14; 1&5-14; 2&5-14; 3&5-14; 1&4-14; 2&3&5-14; 2&4-14.

The present disclosure is further directed to the following non-limiting embodiments.

Embodiment 1. A lubricant composition comprising: about 40 mass % to about 60 mass % of a first oil base stock, wherein the first oil basestock is an API group I basestock or API group II basestock; about 20 mass % to about 45 mass % of a second oil basestock, wherein the second oil basestock comprises an API group II extra heavy basestock, and wherein the API group II extra heavy basestock has: a kinematic viscosity (ASTM D445, 40° C.) of 320 cSt to 520 cSt, a kinematic viscosity (ASTM D445, 100° C.) of 22 cSt to 36 cSt, a viscosity index (ASTM D2270) of 80 to 119, a pour point (ASTM D97) of −6° C. or less, and a saturate content (ASTM D7419) of 90 mass % or greater.

Embodiment 2. The lubricant composition of Embodiment 1, wherein the first oil comprises substantially no group I high viscosity bright stock.

Embodiment 3. The lubricant composition of Embodiment 1, wherein the first oil comprises less than 1 mass % of API group I high viscosity bright stock.

Embodiment 4. The lubricant composition of Embodiment 1, wherein the first oil basestock comprises an API group I basestock, and wherein the API group I basestock has: a kinematic viscosity (ASTM 445, 40° C.) of 15 cSt to 80 cSt, and a pour point (ASTM D97) of −9° C. or less.

Embodiment 5. The lubricant composition of Embodiment 1, wherein the first oil basestock comprises an API group II basestock, and wherein the API group II basestock has: a kinematic viscosity (ASTM 445, 100° C.) of 5 cSt to 10 cSt, and a pour point (ASTM D97) of −10° C. or less.

Embodiment 6. The lubricant composition of any one of Embodiments 1-5, wherein the lubricant composition a kinematic viscosity (ASTM D445, 100° C.) of 12.5 cSt to 26.1 cSt.

Embodiment 7. The lubricant composition of any one of Embodiments 1-6, wherein the lubricant composition has a pour point (ASTM D97) of −21° C. or less.

Embodiment 8. The lubricant composition of any one of Embodiments 1-7, wherein the lubricant composition has a NOACK Volatility (ASTM D5800) of 18 weight percent (mass %) or less.

Embodiment 9. The lubricant composition of any one of Embodiments 1-8, wherein the lubricant composition has a NOACK Volatility (ASTM D5800) from 5 weight percent (mass %) to 15 mass %.

Embodiment 10. The lubricant composition of any one of Embodiments 1-9, wherein the lubricant composition has a Cold-Cranking Simulator test result (ASTM D5293, −15° C.) of 10,000 cP or less.

Embodiment 11. The lubricant composition of any one of Embodiments 1-10, wherein the lubricant composition has a Viscometer Yield Strength (ASTM D4684, −25° C.) of 35 Pa or less.

Embodiment 12. The lubricant composition of any one of Embodiments 1-11, wherein the lubricant composition has an Apparent Viscosity (ASTM D4684, −25° C.) of 60,000 cP or less.

Embodiment 13. The lubricant composition of any one of Embodiments 1-12, wherein the lubricant composition comprises about 5 mass % or less viscosity modifier.

Embodiment 14. The lubricant composition of any one of Embodiments 1-13, wherein the lubricant composition meets or exceeds standards for SAE 20W-50.

Embodiment 15. The lubricant composition of any one of Embodiments 1-14, wherein the API group II extra heavy basestock has: a kinematic viscosity (ASTM D445, 40° C.) of 460 cSt to 520 cSt, a kinematic viscosity (ASTM D445, 100° C.) of 32 cSt to 36 cSt, a viscosity index (ASTM D2270) of 80 to 119, a pour point (ASTM D97) of −15° C. or less, and a saturate content (ASTM D7419) of 98 mass % or greater.

Embodiment 16. A method comprising: operating an engine with an engine oil, the engine oil comprising: about 40 mass % to about 60 mass % of a first oil base stock, wherein the first oil basestock is an API group I basestock or API group II basestock; about 20 mass % to about 45 mass % of a second oil basestock, wherein the second oil basestock comprises an API group II extra heavy basestock, and wherein the API group II extra heavy basestock has: a kinematic viscosity (ASTM D445, 40° C.) of 320 cSt to 520 cSt, a kinematic viscosity (ASTM D445, 100° C.) of 22 cSt to 36 cSt, a viscosity index (ASTM D2270) of 80 to 119, a pour point (ASTM D97) of −6° C. or less, and a saturate content (ASTM D7419) of 90 mass % or greater.

Embodiment 17. The method of Embodiment 16, wherein the API group II extra heavy basestock has: a kinematic viscosity (ASTM D445, 40° C.) of 460 cSt to 520 cSt, a kinematic viscosity (ASTM D445, 100° C.) of 32 cSt to 36 cSt, a viscosity index (ASTM D2270) of 80 to 119, a pour point (ASTM D97) of −15° C. or less, and a saturate content (ASTM D7419) of 98 mass % or greater.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, for example, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “contains”, “containing”, “includes”, “including,” “comprises”, and/or “comprising,” and variations thereof, when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Terms of orientation used herein are merely for purposes of convention and referencing and are not to be construed as limiting. However, it is recognized these terms could be used with reference to an operator or user. Accordingly, no limitations are implied or to be inferred. In addition, the use of ordinal numbers (e.g., first, second, third, etc.) is for distinction and not counting. For example, the use of “third” does not imply there must be a corresponding “first” or “second.” Also, if used herein, the terms “coupled” or “coupled to” or “connected” or “connected to” or “attached” or “attached to” may indicate establishing either a direct or indirect connection, and is not limited to either unless expressly referenced as such.

While the disclosure has described several exemplary embodiments, it will be understood by those skilled in the art that various changes can be made, and equivalents can be substituted for elements thereof, without departing from the spirit and scope of the invention. In addition, many modifications will be appreciated by those skilled in the art to adapt a particular instrument, situation, or material to embodiments of the disclosure without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, or to the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, reference in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, or component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative.

EXAMPLES

Experiment 1A: SAE 20W-50 Formulations

Example SAE 20W-50 lubricant compositions were formed for two different areas: Area A (Example A-1) including an API group I basestock oil as a first oil basestock with an API group II extra heavy basestock oil as a second oil basestock; and Area B (Example B-1) including an API group II basestock oil as a first oil basestock with an API group II extra heavy basestock oil as a second oil basestock. Each area included two comparative example compositions (A-CE-1 and A-CE-2, as well as B-CE-1 and B-CE-2, respectively) comprising an API group I bright stock as a second basestock oil (in lieu of the API group II extra heavy basestock oil). Compositions of example and comparative lubricant compositions for Areas A and B are shown in Table 2 below. AP/E CORE™ 150 is an API group I basestock oil, available from ExxonMobil Corporation. AP/E CORE™ 2500 is an API group I bright stock basestock oil, available from ExxonMobil Corporation. EHC™ 50 is a Group II basestock oil, available from ExxonMobil Corporation. EHC 340 MAX™ is a Group II extra heavy basestock oil, available from ExxonMobil Corporation.

TABLE 2
Compositions in Area A and B.

A-CE-1

A-CE-2

A-1

B-CE-1

B-CE-2

B-1

	Composition (mass %)

AP/E CORE ™ 150	54.00	47.00	47.50
AP/E CORE ™ 2500	24.30	35.50		31.20	42.05
EHC ™ 50				49.00	41.50	43.55
EHC 340 MAX ™			35.00			40.00
Dispersant-Inhibitor Package 1	12.40	12.40	12.40	12.40	12.40	12.40
Viscosity Modifier	9.00	4.80	4.80	7.10	3.75	3.75
Pour Point Depressant	0.30	0.30	0.30	0.30	0.30	0.30

Experiment 1B: Lubricant Characterization Testing

Lubricants compositions formulated in Experiment 1A were tested under various tests according to standards, as listed in Table 3 below.

TABLE 3
Results of testing of Examples.

	Target
	Values	A-CE-1	A-CE-2	A-1	B-CE-1	B-CE-2	B-1

Kinematic Viscosity	18.0-19.5	19.2	18.3	18.7	18.9	18.7	18.7
(cSt) (ASTM D445,
100° C.)
Kinematic Viscosity	—	159.8	164.6	169.6	158.8	171	168.4
(cSt) (ASTM D445,
40° C.)
Cold-Cranking	<9000	5725	9236	8089	5676	9229	7980
Simulator (cP) (ASTM
D5293, −15° C.)
Viscometer Testing:	<35	<35	<35	<35	<35	<35	<35
Yield Strength (Pa)
(ASTM D4684, −20° C.)
Viscometer Testing:	<60,000	21850	36500	19650	17350	25500	17900
Apparent Viscosity (cP)
(ASTM D4684, −20° C.)
Pour Point (° C.) (ASTM	—	−31.5	−39	−39	−33	−30	−40.5
D97)
Noack Volatility (mass	—	10.5	Not	8.7	9.0	Not	7.6
%) (ASTM D5800)			Measured			Measured

The target values listed in Table 3 above were used as representative targets to match the Kinematic Viscosity (ASTM D445, 100° C.) of samples and ensure the samples could reliably meet SAE J300 requirements for SAE 20W-50 in a production environment.

As shown in Table 3 above, Examples A-1 and B-1 were able to achieve a Cold-Cranking Simulator test result (ASTM D5293, −15° C.) of less than 9000 cP, as well as a Pour Point (ASTM D97) of −39° C. or less, and a Noack Volatility (ASTM D5800) of 8.7 mass % or less, while reducing viscosity modifier content by about 50% (as compared to A-CE-1 and B-CE-1, respectively). Furthermore, Examples A-1 and B-1 were able to achieve lower Apparent Viscosity (ASTM D4684, −20° C.) than Examples A-CE-2 and B-CE-2. Additionally, when comparing Examples A-1 and B-1 to A-CE-2 and B-CE-2, respectively, it is clear that compositions of A-1 and B-1 allow for targeted properties with a significant reduction in viscosity modifier usage. Furthermore, when comparing all Examples within Areas A and B, respectively it remains clear that reduction of viscosity modifier without alteration of underlying basestock oil (e.g., in the case of Examples A-CE-2 and B-CE-2) does not achieve the same results as the change in basestock oil (e.g., in Examples A-1 and B-1) when compared with Examples A-CE-1 and B-CE-1.

Experiment 2A: SAE 15W-40 Formulations

Example SAE 15W-40 lubricant compositions were formed for two different areas: Area C (Example C-1) including a premium API CK-4 additive system using API group II basestock oil as a first oil basestock with an API group II extra heavy basestock oil as a second oil basestock; and Area D (Example D-1) including a standard API CK-4 additive system using API group II basestock oil as a first oil basestock with an API group II extra heavy basestock oil as a second oil basestock. Each area included a comparative example composition (C-CE-1 and D-CE-1, respectively) comprising a single API group II medium viscosity basestock oil (with no use of the API group II extra heavy basestock oil). Compositions of example and comparative lubricant compositions for Areas C and D are shown in Table 4 below. EHC™ 45 is a Group II basestock oil, available from ExxonMobil Corporation. EHC™ 65 is a Group II basestock oil, available from ExxonMobil Corporation. EHC 340 MAX™ is a Group II extra heavy basestock oil, available from ExxonMobil Corporation.

TABLE 4
Compositions in Area C and D.

C-CE-1

C-1

D-CE-1

D-1

	Composition (mass %)

EHC ™ 45		55.5		53.9
EHC ™ 65	76.5		78.4
EHC 340 MAX ™		23		28
Dispersant-Inhibitor Package 2	19.2	19.2
Dispersant-Inhibitor Package 3			14.6	14.6
Viscosity Modifier	4	2	7	3.5
Pour Point Depressant	0.3	0.3

Experiment 2B: Lubricant Characterization Testing

Lubricants compositions formulated in Experiment 2A were tested to verify compliance with SAE 15W-40 viscosity grade according to standards, as listed in Table 5 below.

TABLE 5
Results of testing of Examples.

	Target
	Values	C-CE-1	C-1	D-CE-1	D-1

Kinematic Viscosity (cSt)	14.0-15.0	14	14.31 (Est)	14.5	14.7 (Est)
(ASTM D445, 100° C.)
Cold-Cranking	<6800	<6000 (Est)	6531 (Est)	5869	6749 (Est)
Simulator (cP)
(ASTM D5293, −20° C.)
Viscometer Testing: Yield	<35	<35		<35
Strength (Pa)
(ASTM D4684, −25° C.)
Viscometer Testing:	<60,000	17500		19400
Apparent Viscosity (cP)
(ASTM D4684, −25° C.)

The targeted values listed in Table 5 above were used as representative targets to match the Kinematic Viscosity (ASTM D445, 100° C.) of the samples and ensure the samples could reliably meet SAE J300 requirements for SAE 15W-40 in a production environment. Values listed above as (Est) indicate estimated values based on computational simulation.

As shown in Table 5 above, Examples C-1 and D-1 are expected to achieve a Cold-Cranking Simulator test result (ASTM D5293, −20° C.) of less than 6800 cP and Apparent Viscosity (ASTM D4684, −25° C.) of less than 60,000 cP while reducing viscosity modifier content by around 50%.

Therefore, the present invention is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular examples and configurations disclosed above are illustrative only, as the present invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative examples disclosed above may be altered, combined, or modified and all such variations are considered within the scope and spirit of the present invention. The invention illustratively disclosed herein suitably may be practiced in the absence of any element that is not specifically disclosed herein and/or any optional element disclosed herein. While compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions and methods can also “consist essentially of” or “consist of” the various components and steps. All numbers and ranges disclosed above may vary by some amount. Whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range is specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the element that it introduces.

Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth used in the present specification and associated claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the incarnations of the present inventions. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claim, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

One or more illustrative incarnations incorporating one or more invention elements are presented herein. Not all features of a physical implementation are described or shown in this application for the sake of clarity. It is understood that in the development of a physical embodiment incorporating one or more elements of the present invention, numerous implementation-specific decisions must be made to achieve the developer's goals, such as compliance with system-related, business-related, government-related and other constraints, which vary by implementation and from time to time. While a developer's efforts might be time-consuming, such efforts would be, nevertheless, a routine undertaking for those of ordinary skill in the art and having benefit of this disclosure.

While compositions and methods are described herein in terms of “comprising” various components or steps, the compositions and methods can also “consist essentially of” or “consist of” the various components and steps.