Lubricating composition containing phenolic antioxidant and low active sulfur

Abstract

A lubricating composition comprises an oil of lubricating viscosity, a phenolic antioxidant, a sulfurized organic compound having an active sulfur content of no more than 8% by weight, and optionally one or more performance additives selected from the group consisting of succinimide dispersants and detergents. Further, a method for improving the oxidative stability of a lubricating oil in an engine comprises supplying to the engine a lubricating composition comprising an oil of lubricating viscosity, a phenolic antioxidant, a sulfurized organic compound having an active sulfur content of not more than 8% by weight, and optionally one or more performance additives selected from the group consisting of succinimide dispersants and detergents.

Description

Technical Field

[0001] Exemplary embodiments relate to lubricating compositions and find particular application with lubricating compositions containing a phenolic antioxidant and a sulfurized organic compound low in active sulfur that can provide both oxidation resistance and reduced corrosion. Background Art

[0002] Ashless additives (additives that produce little or no ash upon combustion) are commonly used in engine oil formulations to provide performance properties, such as antioxidant properties. Basic ashless additives, such as amines, are often used as antioxidants. Specifically, hydrocarbyl-substituted diphenylamines, such as octyldiphenylamine, dioctyldiphenylamine, and dinonyldiphenylamine, have been used. See, for example, U.S. Patent No. 10,800,992 B2 to Mosier et al., "LUBRICANT COMPOSITIONS FOR DIRECT INJECTION ENGINE," which describes lubricant compositions that may include diarylamine antioxidants, such as dioctyldiphenylamine.

[0003] Substituted diphenylamine (SDPA) antioxidants are known for their ability to inhibit engine oil oxidation. They are widely used in heavy-duty engine oil applications, where oxidation stability is critical for reducing deposit, sludge, and varnish formation, controlling viscosity increase, and thus maintaining optimal engine operation. However, in practice, hydrocarbyl-substituted diphenylamines can be detrimental to corrosion and deposit testing.

[0004] Attempts have been made to replace substituted diphenylamines with similar compounds, such as polymeric diphenylamines. For example, Farng et al., U.S. Publication No. 20190127526A, “ANTIOXIDANT POLYMERIC DIPHENYLAMINE COMPOSITIONS,” describes antioxidant polymer compositions comprising repeating units of diphenylamine monomers that can be combined with base oils and common lubricant additives.

[0005] Others use combinations of antioxidants. For example, Mayhew et al., U.S. Publication No. 20220145204A1, “METHOD OF LUBRICATING AN INTERNAL COMBUSTION ENGINE,” published on May 12, 2022, describes a lubricating composition comprising an antioxidant comprising a mixture of a phenolic antioxidant, an aminic antioxidant, and a sulfurized olefin.

[0006] However, such compositions generally do not provide a combination of good antioxidant properties and reduced corrosion. Achieving both corrosion resistance and oxidation control is challenging, particularly when using sulfur compounds and amine compounds. Furthermore, sulfiding olefins also presents problems. For example, U.S. Patent No. 4,873,006A, entitled "COMPOSITIONS CONTAINING ACTIVE SULFUR," issued to Vinci et al. on October 10, 1989, describes the use of nitrogen-containing carboxylic acid compounds to reduce hydrogen sulfide production from active sulfur compounds.

[0007] There remains a need for a lubricating composition that provides good antioxidant properties while reducing the corrosion tendency of lubricated equipment. Summary of the Invention

[0008] According to one aspect of the exemplary embodiment, a lubricating composition comprises an oil of lubricating viscosity, a phenolic antioxidant, a sulfurized organic compound having an active sulfur content of not more than 8 wt%, and optionally one or more performance additives selected from the group consisting of a succinimide dispersant and a detergent.

[0009] The lubricating composition may be at least substantially free of substituted diphenylamine (SDPA) antioxidants.The lubricating composition may be at least substantially free of aminic antioxidants.

[0010] The phenolic antioxidant may comprise at least 0.1 wt %, or at least 0.5 wt %, or at least 1 wt %, or at least 1.5 wt %, or at least 2 wt % of the lubricating composition. The phenolic antioxidant may comprise no more than 8 wt % of the lubricating composition, or no more than 6 wt %, or no more than 5 wt %, or no more than 4 wt %, or no more than 3 wt % of the lubricating composition.

[0011] The phenolic antioxidant may be selected from hindered phenols, hindered alkylphenol esters, hindered alkoxyphenols, hindered phenol acetates, hindered bisphenols, polyphenols, 4-tert-butylphenol-formaldehyde condensates, 4-tert-butylphenol-acetaldehyde condensates, and mixtures thereof. For example, the phenolic antioxidant may be selected from a mixture of C7-C9 branched alkyl esters of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionic acid; C4 alkyl esters of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionic acid, and 2,2'-thiodiethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

[0012] The sulfurized organic compound is typically a low active sulfur compound. The low active sulfur sulfurized organic compound has a low weight percent active sulfur or a low weight percent active sulfur in the total sulfur of the sulfurized organic compound, or both.

[0013] The sulfurized organic compound may have an active sulfur content of no more than 8 weight percent, or no more than 6 weight percent, or no more than 4.0 weight percent, or no more than 3 weight percent, or no more than 2.5 weight percent, or no more than 2 weight percent. The sulfurized organic compound may have a total sulfur content of at least 0.1 weight percent, or at least 1 weight percent, or at least 1.5 weight percent, or at least 2 weight percent, or no more than 18 weight percent, or no more than 15 weight percent, or no more than 14.0 weight percent, or no more than 12.0 weight percent, or no more than 5 weight percent. The active sulfur may comprise no more than 25 weight percent, or no more than 22 weight percent, or no more than 20 weight percent, or no more than 19 weight percent, or at least 1 weight percent, or at least 1.5 weight percent of the total sulfur in the sulfurized organic compound.

[0014] The sulfurized organic compound may provide at least 0.01 wt%, or at least 0.03 wt%, or at least 0.05 wt%, or up to 0.12 wt%, or up to 0.09 wt% sulfur in the lubricating composition. The sulfurized organic compound may provide no more than 0.02 wt% active sulfur, or no more than 0.018 wt%, or no more than 0.015 wt%, or no more than 0.013 wt% active sulfur in the lubricating composition.

[0015] The sulfurized organic compound may comprise at least 0.1 wt %, or at least 0.15 wt %, or at least 0.2 wt % of the lubricating composition. The sulfurized organic compound may comprise at most 1 wt %, or at most 0.8 wt %, or at most 0.6 wt %, or at most 0.5 wt % of the lubricating composition.

[0016] The sulfurized organic compound may be selected from the group consisting of oligomeric polysulfides, alkyl polysulfides, sulfurized esters, sulfurized alicyclic dialkyl esters, sulfurized alicyclic diene esters, and mixtures thereof.

[0017] The sulfurized organic compound may be selected from oligomeric polysulfides of formula I: R 1 ―S x ―[(C(R') v H 2-v ) n ―S x ] p ―R 2

[0018] Formula I, where R 1 and R 2Each is independently a C2-C20 alkyl, e.g., C3 or C4 or higher alkyl, or C16 or lower alkyl; each R' is independently a C1-C20 alkyl, or C6 or lower alkyl; each n is independently at least 1, or at least 2, or at most 8, e.g., 3-5, such as 3 or 4; p is independently at least 1, or at least 2, or at most 8; each v is 0-2, e.g., v is 0; and each x is independently at least 1.

[0019] The sulfurized organic compound may include an alkyl polysulfide of formula II: R 1 ―S x ―R 2 , where R 1 and R 2 Each is independently a C2-C20 alkyl group or a C3-C8 alkyl group, such as a C4 alkyl group; and each x is independently at least 1.

[0020] The sulfurized organic compound may include a sulfurized fatty acid ester of a fatty alcohol. The sulfurized fatty acid ester of a fatty alcohol may include a sulfurized triglyceride.

[0021] The sulfurized organic compound may include at least one of an alicyclic dialkyl ester and an alicyclic diene ester of Formula V: , where R 13 and R 14 Each of is independently a C2 or higher alkyl or alkenyl group; and x is at least 1.

[0022] The succinimide dispersant may comprise at least 0.2 wt%, or at least 0.5 wt%, or at least 1.0 wt%, or up to 7.0 wt%, or up to 6.0 wt% of the lubricating composition. The succinimide dispersant may provide no more than 0.1 wt% nitrogen to the lubricating composition.

[0023] The detergent may comprise at least 0.1 wt %, or at least 0.2 wt %, or at least 0.25 wt %, or at least 0.4 wt %, or at most 3.0 wt %, or at most 2.0 wt %, or at most 1.5 wt %, or at most 1.25 wt % of the lubricating composition. The detergent may provide at least 0.005 wt % boron, or at least 0.03 wt % boron, or at most 0.06 wt %, or at most 0.04 wt % boron to the lubricating composition. The detergent may provide at least 0.04 wt %, or at least 0.08 wt %, or at most 0.4 wt %, or at most 0.3 wt % calcium to the lubricating composition. The detergent may be selected from alkaline earth metal sulfonates, alkaline earth metal salicylates, alkaline earth metal salicylates, alkaline earth metal salicylates, alkaline earth metal hydrocarbyl-substituted hydroxybenzoates, and mixtures thereof.

[0024] The oil of lubricating viscosity may comprise at least 80 weight percent of the lubricating composition, or may comprise up to 94 weight percent of the lubricating composition.

[0025] The lubricating composition may further comprise at least one of an antiwear agent, a corrosion inhibitor, a viscosity modifier, a pour point depressant, a defoaming agent, an extreme pressure agent, a friction modifier, and combinations thereof. The antiwear agent may provide 300 ppm to 850 ppm by weight of phosphorus to the lubricating composition, based on the total weight of the lubricating composition.

[0026] The viscosity modifier may include a dispersant viscosity modifier comprising at least one of: a reaction product of an olefin polymer comprising carboxylic acid functional groups and 3-nitroaniline; and an amine-functionalized aromatic maleic anhydride-styrene copolymer. The dispersant viscosity modifier may comprise at least 0.01 wt %, or at least 0.1 wt %, or at least 2 wt %, or no more than 8 wt %, or no more than 7 wt % of the lubricating composition.

[0027] The molybdenum may be less than 800 ppm, or less than 400 ppm, or less than 150 ppm, or less than 100 ppm, or less than 80 ppm, or less than 50 ppm, or less than 20 ppm, based on the total weight of the lubricating composition.

[0028] A method for improving the oxidation stability of a lubricating oil in an engine may include supplying the lubricating composition described above to the engine. When the engine is a Volvo T-13 engine and is operated for 360 hours, the kinematic viscosity at 40°C (KV40) may increase from 300 hours to 360 hours to less than 75 or less than 50. Oxidation at the end of the test may be less than 125 A / cm, as measured by IR peak height.

[0029] The lubricating composition described above may be used to lubricate an engine, such as an internal combustion engine or a heavy-duty diesel engine.

[0030] According to another aspect of the exemplary embodiment, the lubricating composition comprises a sulfurized organic compound sufficient to provide at least 0.1% by weight of sulfur in the lubricating composition; at least 0.1% by weight of a phenolic antioxidant; at least 0.1% by weight of a detergent; and at least 2% by weight of a dispersant. The lubricating composition contains no more than 0.04% by weight of active sulfur.

[0031] In the lubricating composition, the detergent may include at least one of a calcium salicylate detergent and a calcium sulfonate detergent sufficient to provide at least 0.1 wt % or at least 0.12 wt % calcium to the lubricating composition; and a magnesium sulfonate detergent sufficient to provide at least 0.02 wt % or at least 0.04 wt % magnesium to the lubricating composition. DETAILED DESCRIPTION

[0032] Aspects of the exemplary embodiments relate to lubricating compositions and methods for lubricating mechanical devices. The compositions provide improved oxidative stability of lubricating oils in mechanical devices while minimizing corrosion of conductive metals.

[0033] As used herein, TBN is measured according to ASTM D2896-21 “Standard Test Method for Base Number of Petroleum Products by Potentiometric Perchloric Acid Titration,” ASTM International, West Conshohocken, PA, 2015, hereinafter D2896.

[0034] In one embodiment, the lubricating composition has a TBN of at least 5, or at least 7. In another embodiment, the lubricating composition has a TBN of no more than 20, or no more than 15, or no more than 12, or no more than 10.

[0035] An exemplary lubricating composition comprises: a) oil of lubricating viscosity, b) phenolic antioxidants, i.e. one or more phenolic antioxidants, c) a sulfurized organic compound, i.e., one or more sulfurized organic compounds, the sulfurized organic compounds being selected to provide a lubricating composition having a low active sulfur content, and d) optionally one or more performance additives, which may be selected from: i) a succinimide dispersant, i.e., one or more succinimide dispersants, and ii) detergents, i.e. one or more detergents, such as alkaline earth metal salts of alkyl sulfonates.

[0036] The lubricating composition may also contain one or more other performance additives.

[0037] The term "active sulfur" of a sulfur-containing compound refers to the relative ability of the sulfur-containing compound to chemically react with metal surfaces to form metal sulfides. As used herein, active sulfur is the weight percentage of sulfur available for reaction at 150°C, as determined by ASTM D1662-19, "Standard Test Method for Active Sulfur in Cutting Oils," hereinafter ASTM D1662. It should be noted that the active sulfur of a sulfur-containing compound is not solely a function of the mole percentage of sulfur it contains, and two sulfur-containing compounds can have very similar mole % (or wt %) sulfur but significantly different wt % active sulfur. The remainder of the sulfur is referred to as inactive sulfur.

[0038] In one embodiment, the lubricating composition is free or substantially free of substituted diphenylamines. "Substantially free" means that the lubricating composition contains no more than 0.1% or no more than 0.01% by weight of substituted diphenylamines. Substituted diphenylamines are defined as anilines having substituents on one or more carbon atoms of the phenyl ring. The substituents can be hydrocarbyl substituents selected from aliphatic substituents (including alicyclic substituents), aromatic substituents, substituents having alkyl and aryl moieties, and mixtures thereof.

[0039] The lubricating composition may have a lubricating 2 / s), or a kinematic viscosity at 100°C (KV_100) of at least 10 cSt, or at least 12 cSt, or at most 25 cSt, or at most 20 cSt, as measured by ASTM D445-21e1 "Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)", hereinafter "D445". The lubricating composition may be a liquid at ambient temperature (15°C-30°C), i.e., not a gel or semi-solid.

[0040] a) Oil of lubricating viscosity

[0041] The lubricating composition comprises an oil of lubricating viscosity. Suitable oils include natural and synthetic oils, oils derived from hydrocracking, hydrogenation and hydrofinishing, unrefined oils, refined oils, rerefined oils or mixtures thereof.

[0042] Oils of lubricating viscosity may also be defined in accordance with the provisions of "Appendix E - API Base Oil Interchangeability Guidelines for Passenger Car Motor Oils and Diesel Engine Oils," April 2008 edition, Section 1.3, Subheading 1.3, "Base Stock Categories." The API guidelines are also summarized in U.S. Patent No. 7,285,516. The five groups of base oils are as follows: Group I (sulfur content > 0.03 wt. %, and / or < 90 wt. % saturates, viscosity index 80-120); Group II (sulfur content > 0.03 wt. %, and / or < 90 wt. % saturates, viscosity index 80-120); Group III (sulfur content > 0.03 wt. %, and / or < 90 wt. % saturates, viscosity index 80-120); Group IV (sulfur content > 0.03 wt. %, and / or < 90 wt. % saturates, viscosity index 80-120); Group V ... < 0.03 wt%, and > 90% by weight saturates, viscosity index 80-120); Class III (sulfur content < 0.03 wt%, and > 90% by weight saturates, viscosity index > 120); Group IV (all polyalphaolefins (PAOs)); Group V (all other oils not included in Groups I, II, III, or IV). Exemplary oils of lubricating viscosity include API Group I, Group II, Group III, Group IV, Group V oils, or mixtures thereof. In some embodiments, the oil of lubricating viscosity is an API Group I, Group II, Group III, or Group IV oil, or mixtures thereof. In some embodiments, the oil of lubricating viscosity is an API Group I, Group II, or Group III oil, or mixtures thereof. In one embodiment, the oil of lubricating viscosity may be an API Group II, Group III mineral oil, a Group IV synthetic oil, or mixtures thereof. In some embodiments, at least 5 weight percent, or at least 10 weight percent, or at least 20 weight percent, or at least 40 weight percent of the lubricating composition is a polyalphaolefin (Group IV). Other groups (subgroups) from which oils of lubricating viscosity may be selected have been defined, including API Group II+ base oils, which refer to Group II base oils having a viscosity index ≥ 110 and less than 120, and API Group III+ base oils having a viscosity index ≥ 130, as described in the SAE publication "Design Practice: Passenger Car Automatic Transmissions," Fourth Edition, AE-29, 2012, pages 12-19. In one embodiment, Group II and / or Group III base oils are used.

[0043] Unrefined, refined, and re-refined oils, as well as natural and synthetic oils, are described, for example, in WO 2008 / 147704 and U.S. Publication No. 2010 / 197536. Synthetic oils can also be produced by the Fischer-Tropsch reaction and are typically hydroisomerized Fischer-Tropsch hydrocarbons or waxes. Oils can be produced by Fischer-Tropsch gas-to-liquid synthesis procedures and other gas-to-liquid procedures.

[0044] Unrefined oils are oils obtained directly from a natural or synthetic source, typically with little or no further purification treatment.

[0045] Refined oils are similar to unrefined oils except that they have been further treated in one or more purification steps to improve one or more properties. Purification techniques are known in the art and include solvent extraction, secondary distillation, acid or base extraction, filtration, percolation, and the like.

[0046] Rerefined oils are also known as reclaimed oils or reprocessed oils and are obtained by processes similar to those used to obtain refined oils, and are often additionally processed by techniques involving the removal of spent additives and oil breakdown products.

[0047] Natural oils include animal oils, vegetable oils (e.g., castor oil), mineral lubricating oils (such as kerosene and solvent-treated or acid-treated paraffinic, cycloparaffinic, or mixed paraffinic-cycloparaffinic mineral lubricating oils), and oils derived from coal or shale, or mixtures thereof. Example animal oils and vegetable oils include long-chain fatty acid esters, such as linseed oil, sunflower oil, sesame seed oil, tallow, lard, palm oil, castor oil, cottonseed oil, corn oil, peanut oil, soybean oil, olive oil, whale oil, menhaden oil, sardine oil, coconut oil, palm kernel oil, babassu oil, rapeseed oil, and soybean oil.

[0048] Synthetic oil can be produced by the Fischer-Tropsch reaction, and can be usually hydroisomerization Fischer-Tropsch hydrocarbon or wax.In one embodiment, oil can be prepared by Fischer-Tropsch gas-to-liquid synthesis procedure and other gas-to-liquid oils.Exemplary synthetic oil comprises hydrocarbon oil, such as polyalphaolefin, synthetic ester and polyester, polyacrylate and polymethacrylate, liquid ester of phosphorus acid and polymerized tetrahydrofuran.

[0049] Example synthetic esters include esters of dicarboxylic acids (e.g., selected from phthalic acid, succinic acid, alkylsuccinic acid, alkenylsuccinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkylmalonic acid, and alkenylmalonic acid) with alcohols (e.g., selected from butanol, hexanol, dodecanol, 2-ethylhexanol, ethylene glycol, diethylene glycol monoether, and propylene glycol). Specific examples of these esters include dibutyl adipate, di(2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, didecyl sebacate, 2-ethylhexyl diester of linoleic acid dimer, and a complex ester formed by reacting 1 mole of sebacic acid with 2 moles of tetraethylene glycol and 2 moles of 2-ethylhexanoic acid. Esters particularly useful as synthetic oils include C5 to C 12 Esters of monocarboxylic acids and polyols and esters prepared from polyol ethers such as neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol and tripentaerythritol. The esters may also be monoesters such as those available under the trade name Priolube 1976 ™ (C 18 -alkyl COO C 20 The synthetic esters useful herein may have a 2.5 mm 2 / s to 30mm 2 / s of KV_100.

[0050] Exemplary synthetic hydrocarbon oils include polymerized and interpolymerized olefins (e.g., polybutene, polypropylene, propylene-isobutylene copolymers); poly(1-hexene), poly(1-octene), poly(1-decene), and mixtures thereof; alkyl-benzenes (e.g., dodecylbenzene, tetradecylbenzene, dinonylbenzene, di-(2-ethylhexyl)-benzene); polyphenylenes (e.g., biphenyl, terphenyl, alkylated polyphenylenes); diphenylalkanes, alkylated diphenylalkanes, alkylated diphenyl ethers, and alkylated diphenyl sulfides, and derivatives, analogs, and homologs thereof, or mixtures thereof.

[0051] Mixtures of such oils are contemplated, such as mixtures of Group II and Group III base oils, or mixtures of Group III and Group IV base oils.

[0052] An oil of lubricating viscosity may have a kinematic viscosity (KV_100) of at least 1.8 cSt or at least 4 cSt at 100°C, as determined in accordance with D445, depending on the desired SAE grade of the lubricating composition. This viscosity may be achieved by a mixture of base oils, for example, a mixture containing a Group I mineral basestock, such as a neutral solvent (e.g., 500 NS or 600 NS), and a bright stock basestock. In admixture with additives, any other combination of mineral or synthetic basestocks or basestocks of vegetable origin having a viscosity compatible with the desired SAE grade may be used.

[0053] The amount of oil of lubricating viscosity present will generally be the balance remaining after subtracting from 100 weight percent the sum of the amounts of the additives as described above and any other performance additives.

[0054] The lubricating composition may be in the form of a concentrate and / or a fully formulated lubricant. If the lubricating composition is in the form of a concentrate (which may be combined with additional oils to form, in whole or in part, a finished lubricating composition), the ratio of the components of the lubricating composition (excluding the oil of lubricating viscosity) to the oil of lubricating viscosity may be from 20:80 to 90:10 by weight, or from 40:60 to 80:20 by weight. If the lubricating composition is in the form of a finished lubricating composition, the ratio of the components of the lubricating composition (excluding the oil of lubricating viscosity) to the oil of lubricating viscosity may be from 1:99 to 30:70 by weight, or from 5:95 to 20:80 by weight.

[0055] In one embodiment, the oil of lubricating viscosity (including diluent oil and oil present due to additives in the composition) comprises at least 20 wt%, or at least 40 wt%, or at least 60 wt%, or at least 80 wt%, or at least 82 wt%, or up to 94 wt%, or up to 92 wt%, or up to 90 wt% of the lubricating composition.

[0056] b) Phenolic antioxidants

[0057] The phenolic antioxidant may be present in the lubricating composition at a total concentration of at least 0.1 wt %, or at least 0.5 wt %, or at least 1 wt %, or at least 1.5 wt %, or at least 2 wt %, or at most 8 wt %, or at most 6 wt %, or at most 5 wt %, or at most 4 wt %, or at most 3 wt % of the lubricating composition.

[0058] Exemplary phenolic antioxidants include hindered phenols, including hindered phenol esters such as phenol alkyl esters, hindered phenol acetates, hindered phenol alkoxides, bisphenols and polyphenols, condensates of phenol with formic acid, and mixtures thereof. Hindered phenolic antioxidants typically contain sec-butyl and / or tert-butyl groups as steric hindering groups. The phenol group can typically be further substituted with a hydrocarbyl group (typically a linear or branched alkyl group) and / or a bridging group to a second aromatic group.

[0059] Exemplary phenolic antioxidants that can be used include: - hindered phenols, such as 2-tert-butylphenol, 2-tert-butyl-4-methylphenol, 2-tert-butyl-5-methylphenol, 2,4-di-tert-butylphenol, 2,6-di-tert-butylphenol, 2,4-dimethyl-6-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4-methoxyphenol, 3-tert-butyl-4-methoxyphenol, 2,5-di-tert-butylhydroquinone, 2,6-di-tert-butyl-4-ethylphenol; 4-methyl-2,6-di-tert-butylphenol, 4-ethyl-2,6-di-tert-butylphenol, 4-propyl-2,6-di-tert-butylphenol, 4-butyl-2,6-di-tert-butylphenol and 4-dodecyl-2,6-di-tert-butylphenol; - hindered alkylphenol esters, such as C7-C9 branched alkyl esters of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionic acid, alkyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid esters, such as n-octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid ester, n-butyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid ester and 2'-ethylhexyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid ester; - hindered alkoxyphenols, such as 2,6-di-tert-butyl-4-alkoxyphenol, for example 2,6-di-tert-butyl-4-methoxyphenol and 2,6-di-tert-butyl-4-ethoxyphenol; - Hindered phenol acetates, such as 3,5-di-tert-butyl-4-hydroxybenzylmercaptooctyl acetate; - Hindered bisphenols such as 2,2'-methylene-bis(4-alkyl-di-tert-butylphenol), for example 2,2'-methylenebis(4-methyl-di-tert-butylphenol) and 2,2-methylenebis(4-ethyl-di-tert-butylphenol), bisphenols such as 4,4'-butylenebis(3-methyl-6-tert-butylphenol), 4,4'-methylenebis(2,6-di-tert-butylphenol), 4,4'-bis(2,6-di-tert-butylphenol), 2,2-(di-p-hydroxyphenyl)propane, 2,2-bis(3,5-di-tert-butyl-4-hydroxyphenyl)propane, 4,4'-cyclohexylenebis(2,6-tert-butylphenol), hexamethylene ethylene glycol-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], triethylene glycol bis[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate], 2,2'-thio-[diethyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 3,9-bis{1,1-dimethyl-2-[3-(3-tert-butyl-4-hydroxy-5-methyl-phenyl)propionyloxy]ethyl}2,4,8,10-tetraoxaspiro[5,5]undecane, 4,4'-thiobis(3-methyl-6-tert-butylphenol) and 2,2'-thiobis(4,6-di-tert-butylresorcinol); - Polyphenols, such as tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, bis-[3,3'-bis(4'-hydroxy-3'-tert-butylphenyl)butyrate]ethylene glycol, 2-(3',5'-di-tert-butyl-4-hydroxyphenyl)methyl-4-(2'',4''-di-tert-butyl-3''-hydroxyphenyl)methyl-6-tert-butylphenol and 2,6-bis(2'-hydroxy-3'-tert-butyl-5'-methylbenzyl)-4-methylphenol; - 4-tert-Butylphenol-formaldehyde condensates and 4-tert-Butylphenol-acetaldehyde condensates; - and mixtures thereof.

[0060] Hindered phenol antioxidants often contain sec-butyl and / or t-butyl groups as sterically hindering groups. The phenol groups can typically be further substituted with hydrocarbyl groups (typically straight or branched alkyl groups) and / or bridging groups to which a second aromatic group is attached. Examples of suitable hindered phenol antioxidants include 2,6-di-t-butylphenol, 4-methyl-2,6-di-t-butylphenol, 4-ethyl-2,6-di-t-butylphenol, 4-propyl-2,6-di-t-butylphenol, 4-butyl-2,6-di-t-butylphenol, and 4-dodecyl-2,6-di-t-butylphenol. In one embodiment, the hindered phenol antioxidant is an ester and can include, for example, Irganox® from BASF. ™L 135 or L 115. Irganox ™ L 135 is a high molecular weight phenolic antioxidant, specifically a mixture of C7-C9 branched alkyl esters of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionic acid. ™ L 115 is 2,6-di-tert-butylphenol. A more detailed description of suitable ester-containing hindered phenol antioxidant chemistry can be found in U.S. Patent No. 6,559,105. In another embodiment, the hindered alkyl phenol is a C4 alkyl ester of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionic acid. In another embodiment, the hindered alkyl phenol is 2,2'-thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

[0061] The coupled phenols useful herein may contain two alkylphenols coupled to an alkylene group to form a bisphenol compound. Examples of suitable coupled phenol compounds include 4,4'-methylenebis(2,6-di-tert-butylphenol); 4-methyl-2,6-di-tert-butylphenol; 2,2'-bis(6-tert-butyl-4-heptylphenol); 4,4'-bis(2,6-di-tert-butylphenol); 2,2'-methylenebis(4-methyl-6-tert-butylphenol) and 2,2'-methylenebis(4-ethyl-6-tert-butylphenol).

[0062] Other phenolic antioxidants can include polyhydroxy aromatic compounds and their derivatives. Examples of suitable polyvalent aromatic compounds include esters and amides of gallic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 1,4-dihydroxy-2-naphthoic acid, 3,5-dihydroxynaphthoic acid, 3,7-dihydroxynaphthoic acid, and mixtures thereof. In one embodiment, the phenolic antioxidant includes a hindered phenol. In another embodiment, the hindered phenol is derived from 2,6-di-tert-butylphenol.

[0063] In one embodiment, the lubricating composition is free or substantially free of substituted diphenylamine (SDPA) antioxidants. This means that the SDPA antioxidant may be present in no more than 0.1 wt %, or no more than 0.01 wt %, or 0 wt % of the lubricating composition.

[0064] Substituted diphenylamines of this type include mono-, di-, tri- and polyalkyl, alkenyl, alkynyl, alkoxyalkyl, alkylamino, aryl, alkylaryl and / or alkoxyaryl substituted diphenylamines, for example C1-C24, especially C6 and higher alkyl substituted diphenylamines such as monooctyldiphenylamine, dioctyldiphenylamine, monobutyl-monooctyldiphenylamine, nonyldiphenylamine, dinonyldiphenylamine, trinonyldiphenylamine, decyldiphenylamine and didecyldiphenylamine. Aniline, as described, for example, in U.S. Patent Nos. 2,943,112; 4,824,601; 5,672,752; 6,204,412; 6,315,925; 6,355,839 and U.S. Publication Nos. 2015 / 0307803 and 2016 / 0017252, and polymers of such monomers, as described, for example, in U.S. Publication No. 20190127526A1. Aryl-substituted diphenylamines include phenyl-α-naphthylamine (PANA) and alkylated phenylnaphthylamines.

[0065] Other aminic antioxidants that may be excluded or substantially absent include 2,6-di-tert-butyl-α-dimethylamino-p-cresol.

[0066] In one embodiment, the lubricating composition is free or substantially free (less than 0.01 wt%, or less than 0.001 wt%, or 0 wt%) of all aminic antioxidants.

[0067] c) Sulfurized organic compounds

[0068] Exemplary sulfurized organic compounds help control wear in lubricated devices such as engines, particularly for extreme pressure conditions in cars, trucks, and industrial engines. They can also have very good thermo-oxidative stability and rust prevention properties.

[0069] Sulfurized organic compounds include those that are substantially nitrogen-free, i.e., do not contain nitrogen functional groups. Sulfurized organic compounds can be formed by sulfurizing an organic compound containing at least one olefinic double bond (non-aromatic double bond), i.e., a double bond connecting two aliphatic carbon atoms. In some cases, the organic compound to be sulfurized may contain a metal cation (e.g., from Group I or Group II, such as sodium, potassium, barium, calcium); a halogen group (e.g., chloro, bromo, or iodo); and / or an oxygen-containing group, such as an ester group.

[0070] Exemplary sulfurized organic compounds include dibenzyl monosulfide and disulfide, isobutylene sulfide, methyl oleate sulfide, alkylphenol sulfide, dipentene sulfide, terpene sulfide, and Diels-Alder adduct sulfide, as well as phosphosulfurized hydrocarbons such as the reaction products of phosphorus sulfide with rosin or methyl oleate, and the like.

[0071] Sulfurized organic compounds or mixtures of compounds particularly useful herein contain little or no active sulfur. Active sulfur compounds contain chains of at least two linked sulfur atoms. Chains of sulfur atoms facilitate molecule breakage between the sulfur atoms, and the resulting reactive sulfur species can cause corrosion of some metals, such as copper. Inactive sulfur compounds contain fewer than two linked sulfur atoms, meaning each sulfur atom is linked to an atom other than sulfur. Some compounds may contain both active and inactive sulfur, with some sulfur present in chains of two or more sulfur atoms and the remainder present as single sulfur atoms.

[0072] The sulfurized organic compound or mixture of sulfurized organic compounds (when two or more such compounds are used) can have an active sulfur content of no more than 8 weight percent, or no more than 6 weight percent, or no more than 5 weight percent, or no more than 4 weight percent, or no more than 3.5 weight percent, or no more than 3 weight percent, or no more than 2.5 weight percent, or as low as 0 weight percent active sulfur as determined by ASTM D1662 at 150° C. In some embodiments, active sulfur comprises at least 0.1 weight percent, or at least 0.5 weight percent, or at least 1.0 weight percent, or at least 1.5 weight percent, or at least 1.8 weight percent of the sulfurized organic compound or mixture of sulfurized organic compounds. When two or more sulfurized organic compounds are employed, the active sulfur content is the average (weighted average) active sulfur content.

[0073] The sulfurized organic compound or mixture of sulfurized organic compounds (when two or more such compounds are used) can have a total sulfur content of at least 1 weight percent, or at least 1.5 weight percent, or at least 2 weight percent, or not more than 18 weight percent, or not more than 15 weight percent, or not more than 14.0 weight percent, or not more than 12.0 weight percent, or not more than 5 weight percent as determined in accordance with ASTM D1552-16 (2021), “Standard Test Method for Sulfur in Petroleum Products by High Temperature Combustion and Infrared (IR) Detection or Thermal Conductivity Detection (TCD)”, hereinafter D1552. When two or more sulfurized organic compounds are employed, the total sulfur content is the average (weighted average) sulfur content.

[0074] In one embodiment, the weight percent of the total sulfur (as measured by ASTM D1552) in the sulfurized organic compound that is active sulfur (as measured by ASTM D1662) may be no more than 25 weight percent, or no more than 22 weight percent, or no more than 20 weight percent, or no more than 19 weight percent, and may be as low as 0 weight percent, or in some embodiments, at least 1 weight percent, or at least 1.5 weight percent, or at least 6 weight percent, or at least 10 weight percent, or at least 15 weight percent. In other words, the weight ratio of active sulfur to sulfur that is not active sulfur in the sulfurized organic compound may be no more than 25:75, or no more than 22:82, or no more than 20:80.

[0075] The sulfurized organic compound may be present in an amount sufficient to provide at least 0.01 wt%, or at least 0.03 wt%, or at least 0.05 wt%, or at most 0.12 wt%, or at most 0.09 wt%, or at most 0.07 wt% sulfur to the lubricating composition. Other sulfur sources in the lubricating composition may provide additional amounts of sulfur.

[0076] The sulfurized organic compound may be present in an amount sufficient to provide no more than 0.04 weight percent active sulfur, or no more than 0.03 weight percent, or no more than 0.025 weight percent, or no more than 0.02 weight percent, or no more than 0.015 weight percent active sulfur to the lubricating composition, and in some embodiments, to provide at least 0.005 weight percent, or at least 0.008 weight percent, or at least 0.01 weight percent active sulfur to the lubricating composition. Generally, the sulfurized organic compound is the sole source of active sulfur in the lubricating composition.

[0077] The sulfurized organic compound may be selected from the group consisting of oligomeric polysulfides, alkyl polysulfides, sulfurized esters, sulfurized alpha olefins, sulfurized fats and sulfurized soybean oil.

[0078] Oligomeric polysulfides may have the general formula shown in Formula I: R 1 ―S x ―[(C(R') v H 2-v ) n ―S x ] p ―R 2 Formula I, where R 1 and R 2 are each independently a C2-C20 alkyl group, such as a C3 or C4 or higher alkyl group, or a C16 or lower alkyl group, Each R' is independently a C1-C20 alkyl group, or a C6 or lower alkyl group; Each n is independently at least 1, or at least 2, or at most 8, for example 3-5, such as 3 or 4; p is independently at least 1, or at least 2, or at most 8; Each v is 0-2, for example, v is 0; and Each x is independently at least 1, and in some cases can be at least 2, or up to 3, or higher, provided that the above-mentioned restrictions on the active sulfur of the sulfurized organic compound are met.

[0079] Generally speaking, (for example, for at least 80% of S x group, or at least 90% S x group, or in some cases for all S x ), the value of x does not exceed 1. Thus, the lubricating composition may be substantially free of compounds of formula (I) wherein x is 4 or higher. In this context, "substantially free" means that no more than 5%, or no more than 2%, or no more than 1%, or no more than 0.5% of S x In the group, x is 4 or higher. Such oligomeric polysulfides and mixtures thereof may have a total sulfur content (ASTM D1552) ranging from 5% to 45% by weight, or at least 10% by weight. Such oligomeric polysulfides and mixtures thereof may have an active sulfur content (ASTM D1662) ranging from 0.5% to 10% by weight, or up to 9% by weight.

[0080] The alkyl polysulfide may have the general formula shown in Formula II: R 1 ―S x ―R 2 Formula II, where R 1 and R 2 are each independently a C2-C20 alkyl group, such as a C3 or higher alkyl group, or a C16 or lower alkyl group; and Each x is independently at least 1, and in some cases can be at least 2, or at most 3, or more, provided that the above-mentioned limits on active sulfur in the sulfurized organic compound are met. This generally means that the value of x does not exceed 1.5, or does not exceed 1.2 on average, and that the lubricating composition is substantially free of compounds of Formula II wherein x is 4 or more.

[0081] Such alkyl polysulfides and mixtures thereof may have a total sulfur content (ASTM D1552) in the range of 5% to 20% by weight, or at least 10% by weight. Such alkyl polysulfides and mixtures thereof may have an active sulfur content (ASTM D1662) in the range of 0.5% to 45% by weight, or up to 10% by weight, or up to 9% by weight, or up to 5% by weight. The molecular weight may be in the range of 200 Daltons to 2000 Daltons.

[0082] Exemplary sulfurized esters include sulfurized fatty acid esters of fatty alcohols such as glycerol, for example, monoglycerides, diglycerides, and triglycerides, such as the sulfurized triglycerides of the general formula shown in Formula III: CH2―O―C(=O)―R 3 │ CH2―O―C(=O)―R 4 │ CH2―O―C(=O)―R 5 Formula III, where R 3 、R 4 and R 5 are each independently a C8 or higher alkyl or alkenyl group, or a C10 or higher alkyl or alkenyl group, or up to a C30 or up to a C24 alkyl or alkenyl group; and where R 3 、R 4 and R 5 At least one of them is connected to the sulfur atom of the sulfur-containing part, the middle end of the alkyl group.

[0083] An exemplary sulfur-containing moiety may have the following general formula: ―S x ―, which is in R 3 、R 4 and R 5 a connection between the two; or ―S x ―R 6 , where R 6 is a C4 or higher, or C6 or higher, or C8 or higher, or C10 or higher, or up to C50 straight chain or branched alkyl or alkenyl group, such as -CH2CH=CHCH2(CH2CH2) q CH3, wherein q is at least 5, or at least 10, or at most 15; or a mixture thereof; wherein each x is independently at least 1, and in some cases can be at least 2, or up to 3, or higher, but is substantially free of compounds of formula II wherein x is 4 or higher, provided that the above limitations on the active sulfur of the sulfurized organic compound are met.

[0084] An exemplary sulfurized fatty acid ester is a sulfurized triglyceride of the general formula shown in Formula IV:

[0085] Formula IV, where R 6 As mentioned above, for example, CH2CH=CHCH2(CH2CH2) 13-15 CH3; R 7 、R 8 、R 9 、R 10 、R 11 and R 12 Each of which is independently a C2 to C8 alkyl or alkenyl group, for example, R 7 (CH2)6, R 8 (CH2)6CH3, R 9 (CH2)7, R 10 (CH2)5CH3, R 11 is (CH2)6, and R 12 is (CH2)6CH3; And each x is independently as described above.

[0086] The total sulfur content (ASTM D1552) of the sulfurized triglyceride according to Formula IV may be at least 5 weight percent, or at least 7 weight percent, or at most 15 weight percent, or at most 12 weight percent.

[0087] The active sulfur (ASTM D1662) of the sulfurized ester or mixture thereof may be less than 5 wt%, for example 3 wt% to 4 wt%.

[0088] Other sulfurized esters include sulfurized alicyclic dialkyl and diene esters of the general formula shown in Formula V:

[0089] Formula V, where R 13 and R 14 each of which is independently a C2 or higher alkyl group, such as a C3 or higher, or C4 or higher, or up to C10, or up to C6 alkyl or alkenyl group, for example a straight chain C4 alkyl group; and x is as described above, for example, x is 1 or 2.

[0090] The sulfur content of the sulfurized alicyclic diester can be at least 5% by weight, or at least 10% by weight, or at most 15% by weight, such as 10% by weight to 14% by weight, and the active sulfur can be from 1% by weight to 5% by weight. For example, the active sulfur content of a mixture of sulfurized alicyclic dibutyl esters of the form shown in Formula V can be at least 1% by weight, or at least 1.5% by weight, or at most 5% by weight, such as at most 3% by weight.

[0091] Example sulfurized organic compounds include sulfurized olefins (sulfurized chain alkenes), which can be obtained by reacting a sulfurizing agent with an olefin such as isobutylene in the presence of a catalyst. The sulfurizing agent includes elemental sulfur, hydrogen sulfide, sulfur halides, sodium sulfide, and a mixture of hydrogen sulfide and sulfur or sulfur dioxide. The amount of the sulfurizing agent used can be calculated based on the total olefinic unsaturated groups of the mixture. For example, 0.5 to 1.2 moles of sulfur are used per mole of olefinic bonds. The olefin compound can contain 2 to 50 carbon atoms.

[0092] Exemplary sulfurized olefins can be obtained from isobutylene, sulfur, and hydrogen sulfide by reacting mercaptans and sulfur in the presence of a basic catalyst using a catalytic process using a solid catalyst, such as the solid catalysts described in U.S. Pat. Nos. 6,472,354 B2 and 4,876,389 A. They can also be produced by a two-step process, such as that described in U.S. Pat. No. 4,937,385 A, which comprises synthesizing mercaptans from alkenes and H2S in the presence of a solid catalyst, and then reacting the mercaptans with sulfur and another heterogeneous catalyst to form sulfurized olefins.

[0093] Sulfurized olefins such as those shown in Formula IV can be prepared as described in U.S. Patent No. 4,957,651. The process employs a co-sulfurized mixture of two or more reactants selected from the group consisting of: (1) at least one fatty acid ester of a polyol, (2) at least one fatty acid, (3) at least one olefin, and (4) at least one fatty acid ester of a monool. Reactant (3) (olefin component) includes at least one olefin. The olefin can be an aliphatic olefin having 4 to 40 carbon atoms, such as 8 to 36 or 12 to 18 carbon atoms. Terminal olefins or α-olefins are particularly suitable, especially those having 12 to 20 carbon atoms.

[0094] The sulfurized organic compound of formula V may be the reaction product of a sulfurizing agent and at least one Diels-Alder adduct in a molar ratio of at least 0.75:1. The molar ratio of the sulfur source to the Diels-Alder adduct may be from 0.75:1 to 1:1.2. The Diels-Alder adduct may be composed of at least one compound consisting of —C(O)O—R o The dienophile of the carboxylate group represented by o is the residue of a saturated fatty alcohol having up to 40 carbon atoms, —R oThe fatty alcohol derived therefrom is a monohydric or polyhydric alcohol which may be selected from alkylene glycols, alkanols, alkoxy-substituted alkanols, ethanol, ethoxyethanol, propanol, butanol, β-diethylamino-ethanol, dodecanol, diethylene glycol, tripropylene glycol, tetrabutylene glycol, hexanol, octanol, isooctyl alcohol and mixtures thereof. Generally, there will be no more than two —C(O)O—R o group, and in one embodiment, only one —C(O)O—R o These substances can also be described as cyclohexene compounds with ester substituents. An example of a sulfurized organic compound of this type is 4-butoxycarbonylcyclohexene sulfide. This and other sulfurized organic compounds can be further treated with other substances such as aryl phosphates (e.g., triphenyl phosphite).

[0095] The sulfurization reaction can be carried out at elevated temperature (eg, 50-350°C or 100-200°C), with efficient stirring and typically in an inert atmosphere such as nitrogen, optionally in the presence of an inert solvent.

[0096] d) Performance additives

[0097] i) Dispersants

[0098] The lubricating composition optionally further comprises at least one dispersant. Exemplary dispersants include succinimide dispersants, Mannich dispersants, succinamide dispersants, and polyolefin succinates, amides, and ester-amides, and mixtures thereof.

[0099] In an exemplary embodiment, the dispersant includes at least one succinimide dispersant. The dispersant can be an N-substituted long chain alkenyl succinimide. An example of an N-substituted long chain alkenyl succinimide is polyisobutylene succinimide. The polyisobutylene from which the polyisobutylene succinic anhydride is derived has a number average molecular weight M of at least 300, or at least 350, or at least 500, or at least 550, or at least 750, or at least 1000. nand can be up to 5000, or up to 3000, or up to 2500. Such succinimides can be formed, for example, from high vinylidene polyisobutylene and maleic anhydride. Succinimide dispersants and their preparation are disclosed, for example, in U.S. Pat. Nos. 3,172,892, 3,219,666, 3,316,177, 3,340,281, 3,351,552, 3,381,022, 3,433,744, 3,444,170, 3,467,668, 3,501,405, 3,542,680, 3,576,743, 3,632,511, 4,234,435, Re 26,433, 6,165,235, and 7,238,650, and in EP 0 355 895 A2.

[0100] In one embodiment, the succinimide dispersant is derived from 1800M n Up to 2200M n A polyisobutylene succinimide dispersant of polyisobutylene containing 0.80 wt% to 1.0 wt% nitrogen.

[0101] In certain embodiments, the dispersant may be a polyolefin succinate, amide, or ester-amide. The polyolefin succinate-amide may be polyisobutylene succinic acid reacted with an alcohol (such as pentaerythritol) and a polyamine. Example polyolefin succinates include polyisobutylene succinate of pentaerythritol and mixtures thereof.

[0102] Exemplary dispersants can also be post-treated by conventional methods by reacting with any of a variety of reagents. These include boron compounds (such as boric acid), urea, thiourea, dithiothiadiazoles, carbon disulfide, aldehydes, ketones, carboxylic acids (such as terephthalic acid), hydrocarbon-substituted succinic anhydride, maleic anhydride, nitriles, epoxides, and phosphorus compounds. In one embodiment, the post-treated dispersant is borated. In one embodiment, the post-treated dispersant is reacted with dithiothiadiazoles. In one embodiment, the post-treated dispersant is reacted with phosphoric acid or phosphorous acid. In one embodiment, the post-treated dispersant is reacted with terephthalic acid and boric acid (as described in, for example, U.S. Publication No. 20090054278A1), which can be derived from an aliphatic polyamine or a mixture thereof. The aliphatic polyamine can be ethylene polyamine, propylene polyamine, butylene polyamine, or a mixture thereof. In one embodiment, the aliphatic polyamine can be ethylene polyamine. In one embodiment, the aliphatic polyamine may be selected from the group consisting of ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, polyamine still bottoms, and mixtures thereof.

[0103] For purposes of expressing the amounts of components in the compositions, dispersant viscosity modifiers are classified as viscosity modifiers rather than dispersants.

[0104] When present, the lubricating composition may comprise a total of at least 0.01 wt%, or at least 0.1 wt%, or at least 0.2 wt%, or at least 0.5 wt%, or at least 1 wt%, or at least 1.5 wt%, or at least 2 wt%, or at least 3 wt% dispersant, and in some embodiments, up to 15 wt%, or up to 10 wt%, or up to 8 wt%, or up to 7 wt%, or up to 5 wt% of such dispersant.

[0105] In one embodiment, the lubricating composition comprises at least 0.2 wt%, or at least 0.5 wt%, or at least 1.0 wt%, or up to 7.0 wt%, or up to 6.0 wt% of a succinimide dispersant, which may be borated or otherwise post-treated.

[0106] ii) Detergent

[0107] The lubricating composition optionally further comprises at least one detergent. Detergents are additives that reduce the formation of deposits on lubricated surfaces, such as high-temperature varnish and lacquer deposits on piston surfaces in engines. Exemplary detergents useful herein include metal-containing detergents, which may be neutral or overbased.

[0108] The metal of the metal-containing detergent can be zinc, sodium, calcium, barium or magnesium. The metal-containing detergent can be selected from sulfonates, sulfur-free phenates, sulfur-containing phenates, salicylates, salicylates and mixtures thereof or their borated equivalents. The metal-containing detergent can be borated with a borated agent such as boric acid.

[0109] Metal-containing detergents may also include "hybrid" detergents formed with mixed surfactant systems including phenate and / or sulfonate components, for example, phenate / salicylate, sulfonate / phenate, sulfonate / salicylate, sulfonate / phenate / salicylate, as described, for example, in U.S. Patent Nos. 6,429,178; 6,429,179; 6,153,565; and 6,281,179. In the case of a mixed sulfonate / phenate detergent, the mixed detergent would be considered equivalent to the amounts of different phenate and sulfonate detergents incorporating the same amounts of phenate and sulfonate soap, respectively.

[0110] Example overbased metal-containing detergents include sulfonates, phenates (including sulfur-containing and non-sulfur-containing phenates), salicylates, and hydroxybenzoates such as zinc, sodium, calcium, and magnesium salicylates, which may be substituted with hydrocarbyl groups. Such overbased sulfonates, salicylates, phenates, and salicylates may have a total base number (TBN) of 120 to 700, or 250 to 600, or 300 to 500 (on an oil-free basis).

[0111] Example sulfonate detergents include linear and branched alkylbenzene sulfonate detergents and mixtures thereof, which can have a metal ratio of at least 8, as described, for example, in U.S. Publication No. 2005065045. The linear alkylbenzene can have a benzene ring attached anywhere on the linear chain (typically at the 2-, 3-, or 4-positions), or a mixture thereof. In one embodiment, the alkylbenzene sulfonate detergent can be a branched alkylbenzene sulfonate, a linear alkylbenzene sulfonate, or a mixture thereof. The sulfonate detergent can be a metal salt of one or more oil-soluble alkyltoluene sulfonate compounds, as described in U.S. Publication No. 20080119378 A1.

[0112] Examples of hydrocarbyl-substituted hydroxybenzoate detergents include neutral and overbased alkaline earth metal C10 to C40 hydrocarbyl-substituted hydroxybenzoates, particularly C10 to C40 hydrocarbyl-substituted salicylates, as described, for example, in US Publication No. 20100062958A1.

[0113] For example, the detergent may include one or more of an overbased hydrocarbyl-substituted calcium hydroxybenzoate detergent (e.g., calcium salicylate detergent), an overbased calcium sulfonate detergent, and a magnesium sulfonate detergent. The calcium salicylate detergent may be present in an amount sufficient to provide at least 0.02% by weight Ca, such as at least 0.04% by weight, or at most 0.3% by weight, or at most 0.2% by weight, or at most 0.15% by weight Ca to the lubricating composition. The overbased calcium sulfonate detergent may be present in an amount sufficient to provide at least 0.02% by weight Ca, such as at least 0.04% by weight, or at most 0.2% by weight, or at most 0.15% by weight Ca in the lubricating composition. The magnesium sulfonate detergent may be neutral or overbased, such as an overbased sulfonate detergent having a metal ratio of 12 to 20, or 12 to 18, or 20 to 30, or 22 to 25. The magnesium sulfonate detergent may be present in an amount sufficient to provide at least 0.01 wt % Mg in the lubricating composition, such as at least 0.02 wt %, or at most 0.1 wt %, or at most 0.06 wt % Mg. One or more of these detergents may be borated sufficient to provide at least 0.005 wt % boron, or at least 0.03 wt % boron, or at most 0.06 wt %, or at most 0.04 wt % boron in the lubricating composition.

[0114] In one embodiment, the lubricating composition comprises a total of at least 0.1 wt%, or at least 0.2 wt%, or at least 0.25 wt%, or at least 0.4 wt%, or at most 3.0 wt%, or at most 2.0 wt%, or at most 1.5 wt%, or at most 1.25 wt% detergent.

[0115] The lubricating composition may also contain one or more of the following other performance additives: iii. Anti-wear agent The lubricating composition optionally further comprises at least one anti-wear agent other than a sulfurized organic compound. Examples of suitable anti-wear agents suitable for use herein include metal dihydrocarbyl dithiophosphates (such as zinc dialkyl dithiophosphate (ZDDP)), titanium compounds, tartrates, tartrimides, oil-soluble amine salts of phosphorus compounds, phosphites (such as dibutyl phosphite), phosphonates, thiocarbamate-containing compounds (such as thiocarbamates, thiocarbamate amides, thiocarbamate ethers, alkylene-coupled thiocarbamates, and bis(S-alkyldithiocarbamoyl)disulfides).

[0116] In one embodiment, the antiwear agent comprises zinc dialkyl dithiophosphate.The alkyl group of the dialkyl dithiophosphate may be linear or branched and may contain from 2 to 20 carbon atoms, provided that the total number of carbons is sufficient to render the zinc dialkyl dithiophosphate soluble in oil. Examples of suitable zinc dialkyl dithiophosphates (ZDDPs) include zinc di(2-methylpropyl)dithiophosphate, zinc di(pentyl)dithiophosphate, zinc di(1,3-dimethylbutyl)dithiophosphate, zinc di(heptyl)dithiophosphate, zinc di(octyl)dithiophosphate, zinc di(2-ethylhexyl)dithiophosphate, zinc di(nonyl)dithiophosphate, zinc di(decyl)dithiophosphate, zinc didodecyldithiophosphate, zinc didodecylphenyldithiophosphate, zinc di(heptylphenyl)dithiophosphate, and ZDDPs prepared from mixed alcohols such as methylpropyl and amyl alcohol, 2-ethylhexyl and isopropyl alcohol, 4-methyl-2-pentyl and isopropyl alcohol, and mixtures thereof.

[0117] In one embodiment, the ZDDP comprises at least 0.1 wt%, or at least 0.25 wt%, or at least 0.5 wt%, or at most 5 wt%, or at most 4 wt%, or at most 3 wt% of the lubricating composition.

[0118] In one embodiment, the ZDDP is present in an amount sufficient to provide at least 0.03 wt%, or at least 0.06 wt%, or at most 0.5 wt%, or at most 0.1 wt% Zn in the lubricating composition.

[0119] In another embodiment, the antiwear agent may include a tartrate or tartrimide, as described in U.S. Publication Nos. 2006 / 0079413; 2006 / 0183647; and 2010 / 0081592. The tartrate or tartrimide may contain an alkyl ester group, wherein the total number of carbon atoms in the alkyl group is at least 8. In one embodiment, the antiwear agent may include a citrate, as disclosed in U.S. Publication No. 20050198894.

[0120] In one embodiment, the lubricating composition is free of or substantially free of metal-containing antiwear agents. In other embodiments, the lubricating composition is free of or substantially free of phosphorus-containing antiwear agents. For example, phosphorus-containing antiwear agents are absent, or, when present, are present in an amount that provides no more than 0.8% by weight of phosphorus, or no more than 0.15% by weight of phosphorus to the lubricating composition. For example, a C3 / 6 blended secondary ZDDP may be present at up to 1.2% by weight, or at most 1% by weight, or at most 0.5% by weight.

[0121] When present, the lubricating composition may comprise at least 0.01 wt%, or at least 0.1 wt%, or at least 0.25 wt%, or at least 0.5 wt% antiwear agent, and in some embodiments, at most 5 wt%, or at most 4 wt%, or at most 3 wt% antiwear agent.

[0122] iv) Extreme pressure (EP) agents

[0123] In addition to sulfurized organic compounds having low active sulfur content, the lubricating composition may also contain extreme pressure agents. Examples of such non-sulfur EP agents include chlorinated waxes; phosphorus esters such as dihydrocarbon phosphites and trihydrocarbon phosphites, for example, dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, amylphenyl phosphite, diamylphenyl phosphite, tridecyl phosphite, distearyl phosphite, and polypropylene-substituted phenol phosphites; and barium heptylphenol diacid; amine salts of alkyl and dialkyl phosphoric acids and their derivatives, including, for example, amine salts of the product of the reaction of dialkyl dithiophosphoric acids with propylene oxide and subsequent further reaction with P2O5; and mixtures thereof. Other useful extreme pressure agents are described in U.S. Patent No. 3,197,405.

[0124] When present, the lubricating composition may comprise at least 0.01 wt%, or at least 0.1 wt%, or at least 0.5 wt% extreme pressure agent, and in some embodiments, at most 3 wt%, or at most 1.5 wt%, or at most 0.9 wt% extreme pressure agent.

[0125] v. Foam inhibitor

[0126] The lubricating composition may contain a foam suppressor. Foam suppressors useful in lubricant compositions include polysiloxanes; copolymers of ethyl acrylate and 2-ethylhexyl acrylate and optionally vinyl acetate; demulsifiers include fluorinated polysiloxanes, trialkyl phosphates, polyethylene glycols, polyethylene oxide, polypropylene oxide, and (ethylene oxide-propylene oxide) polymers.

[0127] When present, the lubricating composition may comprise at least 0.005 wt%, or at least 0.08 wt% of a foam inhibitor, and in some embodiments, at most 3 wt%, or at most 1.5 wt%, or at most 0.4 wt% of a foam inhibitor.

[0128] vi. Viscosity modifier

[0129] Lubricating compositions may include a viscosity modifier. Viscosity modifiers (sometimes also called viscosity index improvers or viscosity modifiers) useful in lubricant compositions are typically polymers, including polyisobutylene, polymethacrylates (PMAs) and polymethacrylates; diene polymers, polyalkylstyrenes, esterified styrene-maleic anhydride copolymers, hydrogenated alkenyl aromatic hydrocarbon-conjugated diene copolymers (such as styrene-butadiene copolymer resin (SBR)); and polyolefins, also known as olefin copolymers or OCPs. PMAs are prepared from a mixture of methacrylate monomers with varying alkyl groups. The alkyl groups can be linear or branched, containing 1 to 18 carbon atoms. Most PMAs are viscosity modifiers as well as pour point depressants. In one embodiment, the viscosity modifier comprises a styrene-butadiene resin. In another embodiment, the viscosity modifier comprises a polyolefin containing ethylene and one or more higher olefins, such as propylene.

[0130] In one embodiment, the viscosity modifier includes one or more dispersant viscosity modifiers (DVMs). DVMs provide dispersibility and viscosity adjustment. Example DVMs are made from polymers, such as olefin polymers (e.g., ethylene propylene copolymers) and / or vinyl aromatic polymers (e.g., polystyrene), that have been free-radically grafted with an ethylenically unsaturated carboxylic acid material (e.g., maleic anhydride) functionalized with one or more amines and / or pendant functional groups having sulfonate functional groups. This type of DVM is disclosed in, for example, U.S. Patent Nos. 4,863,623; 5,264,140; 5,409,623; 6,107,257; 6,107,258; 6,117,825; U.S. Publication Nos. 20120178656A1; 20120178659A1; 20090305923A1 and 20170283733A1.

[0131] When present, the lubricating composition may comprise at least 0.01 wt%, or at least 0.1 wt%, or at least 0.2 wt%, or at least 0.4 wt% of a viscosity modifier (including a dispersant viscosity modifier), and in some embodiments, up to 10 wt%, or up to 5 wt%, or up to 4 wt%, or up to 2 wt% of such a viscosity modifier. In one embodiment, the lubricating composition comprises at least 0.2 wt%, or at least 0.3 wt%, or at least 0.5 wt%, or up to 3.0 wt%, or up to 2.0 wt% of a dispersant viscosity modifier, which may be borated or otherwise post-treated.

[0132] In some embodiments, no viscosity modifier is used.

[0133] vii. Corrosion inhibitors and metal passivators

[0134] The lubricating composition may include a corrosion inhibitor. Corrosion inhibitors / metal passivators useful in exemplary lubricating compositions include fatty amines, octylamine octanoate, condensation products of dodecenylsuccinic acid or anhydride and fatty acids (such as oleic acid with a polyamine), derivatives of benzotriazole (e.g., tolyltriazole), 1,2,4-triazole, benzimidazole, 2-alkyldithiobenzimidazole, and 2-alkyldithiobenzothiazole.

[0135] When present, the lubricating composition may contain at least 0.005 wt%, or at least 0.01 wt%, or at least 0.015 wt%, or at least 0.02 wt% of the corrosion inhibitor, and in some embodiments, at most 5 wt%, or at most 2.5 wt%, or at most 0.1 wt% of the corrosion inhibitor. In some embodiments, no corrosion inhibitor is used.

[0136] viii. Pour Point Depressants

[0137] The lubricating composition may include a pour point depressant. Pour point depressants that can be used in exemplary lubricating compositions include polyalphaolefins, esters of maleic anhydride-styrene copolymers, polymethacrylates, polyacrylates, and polyacrylamides. In one embodiment, the pour point depressant is maleic anhydride-styrene copolymer.

[0138] When present, the lubricating composition may contain at least 0.005 wt%, or at least 0.01 wt%, or at least 0.1 wt%, or at least 0.15 wt% of a pour point depressant, and in some embodiments, up to 5 wt%, or up to 2 wt%, or up to 1 wt% of a pour point depressant. In some embodiments, no pour point depressant is used.

[0139] ix. Friction modifier

[0140] The lubricating composition may include a friction modifier. Friction modifiers that can be used in exemplary lubricating compositions include fatty acid derivatives, such as amines, esters, epoxides, fatty imidazolines, carboxylic acids, and condensation products of polyalkylene-polyamines, and amine salts of alkylphosphoric acids. The friction modifier may be an ashless friction modifier. Such friction modifiers are those that generally do not produce any sulfated ash when subjected to the conditions of ASTM D874-13a (2018). If the additive does not contribute metal content to the lubricant composition, it is referred to as "metal-free." As used herein, the term "fatty alkyl" or "fat" with respect to friction modifiers refers to a carbon chain having 8 to 30 carbon atoms, typically a straight carbon chain.

[0141] In one embodiment, the ashless friction modifier may be represented by the formula:

[0142] Wherein, D and D' are independently selected from -O-, >NH, >NR 23 , by combining the D and D' groups and forming R between the two >C=O groups 21 -N< group to form an imide group; E is selected from –R 24 -OR 25 -、>CH2、>CHR 26 、>CR 26 R 27 、>C(OH)(CO2R 22 )、>C(CO2R 22 )2 and>CHOR 28 ; where R 24 and R 25 Independently selected from >CH2, >CHR 26 、>CR 26 R 27 、>C(OH)(CO2R 22 ) and >CHOR 28 q is 0 to 10, provided that when q=1, E is not>CH2, and when n=2, both E are not>CH2; p is 0 or 1; R 21 are independently hydrogen or a hydrocarbyl group typically containing 1 to 150 carbon atoms, provided that when R 21 When it is hydrogen, p is 0, and q is greater than or equal to 1; R 22 is a hydrocarbon group generally containing 1 to 150 carbon atoms; R 23 、R 24 、R 25 、R 26 and R 27 are independently a hydrocarbyl group; and R 28is hydrogen or a hydrocarbyl group typically containing 1 to 150 carbon atoms, or 4 to 32 carbon atoms, or 8 to 24 carbon atoms. In certain embodiments, the hydrocarbyl group R 23 、R 24 and R 25 The alkyl group may be straight-chain or predominantly straight-chain.

[0143] In certain embodiments, the ashless friction modifier is a fatty ester, amide, or imide of various hydroxy-carboxylic acids, such as tartaric acid, malic acid, lactic acid, glycolic acid, and mandelic acid. Examples of suitable materials include di(2-ethylhexyl) tartrate (i.e., di(2-ethylhexyl) tartrate), di(C8-C8 tartrate), di(C9-C10 tartrate), di(C11-C12 tartrate, di(C12-C13 tartrate), di(C16-C17 tartrate), di(C18-C19 tartrate), di(C20-C19 tartrate), di(C30-C18 tartrate), di(C40-C19 tartrate), di(C5-C19 tartrate), di(C6-C19 tartrate), di(C7-C18 tartrate), di(C8-C19 tartrate), di(C9-C19 tartrate), di(C18-C19 tartrate 10 ) ester, tartaric acid di(C 12 - 15 ) esters, dioleoyl tartarate, oleoyl triamide, and oleoyl maleimide.

[0144] In certain embodiments, the ashless friction modifier may be selected from long-chain fatty acid derivatives of amines, fatty esters, or fatty epoxides; fatty imidazolines, such as condensation products of carboxylic acids and polyalkylene polyamines; amine salts of alkyl phosphoric acids; fatty alkyl tartaric acids; fatty alkyl tartarimides; fatty alkyl tartaramides; fatty phosphonates; fatty phosphites; borated phospholipids, borated fatty epoxides; glycerides; borated glycerides; fatty amines; alkoxylated fatty amines; borated alkoxylated fatty amines; hydroxy and polyhydroxy fatty amines, including tertiary hydroxy fatty amines; hydroxyalkylamides; metal salts of fatty acids; metal alkyl salicylates; fatty oxazolines; fatty ethoxylated alcohols; condensation products of carboxylic acids and polyalkylene polyamines; or reaction products from fatty carboxylic acids with guanidine, aminoguanidine, urea, or thiourea and their salts.

[0145] Friction modifiers may also encompass materials such as sulfurized fatty compounds and olefins, sunflower oil or soybean oil monoesters of polyols and aliphatic carboxylic acids.

[0146] In another embodiment, the friction modifier may be a long chain fatty acid ester. In another embodiment, the long chain fatty acid ester may be a monoester, and in another embodiment the long chain fatty acid ester may be a triglyceride.

[0147] The amount of ashless friction modifier in the lubricant can be 0.1% to 3% by weight (or 0.12% to 1.2% or 0.15% to 0.8% by weight). The material can also be present alone or in a concentrate with other additives and a smaller amount of oil. In a concentrate, the amount of material can be two to ten times the amount in the above concentration.

[0148] In some embodiments, the lubricating composition is free or substantially free of friction modifiers, e.g., contains no more than 0.001 wt % of a friction modifier. In other embodiments, the friction modifier may comprise at least 0.01 wt %, or at least 0.05 wt %, or at least 0.1 wt %, or at most 6 wt %, or at most 4 wt %, or at most 2 wt % of the lubricating composition.

[0149] Molybdenum compounds

[0150] In one embodiment, the lubricating composition contains a molybdenum compound. The molybdenum compound can serve various functions in the lubricating composition, such as an antiwear agent, a friction modifier, and an antioxidant.

[0151] For ease of description, the amount of molybdenum compound is not included in the amounts of antiwear agents, friction modifiers, and antioxidants described elsewhere.

[0152] Molybdenum-containing antiwear and antioxidant agents include molybdenum hydrocarbyl dithiocarbamates, molybdenum hydrocarbyl dithiocarbamate dimer complexes, and other molybdenum and sulfur-containing compounds, such as those described, for example, in U.S. Patent No. 4,285,822. Other molybdenum-containing materials include molybdenum dihydrocarbyl dithiophosphates; molybdenum-amine compounds such as those described in U.S. Patent No. 6,329,327; organo-molybdenum compounds prepared by reacting a molybdenum source, a fatty oil, and a diamine, such as those described in U.S. Patent No. 6,914,037; and trinuclear molybdenum-sulfur complexes such as those described in U.S. Patent No. 6,232,276. Other molybdenum compounds are disclosed in U.S. Publication No. 20080280795.

[0153] The molybdenum amine compound can be prepared by reacting a compound containing a hexavalent molybdenum atom with a compound having the formula NR 29 R 30 R 31 Represented by the reaction of primary amine, secondary amine or tertiary amine, wherein R 29 、R 30 and R 31 Each of is independently hydrogen or a hydrocarbyl group having 1 to 32 carbon atoms, and wherein R 29 、R 30 and R 31 At least one of is a hydrocarbyl group having 4 or more carbon atoms or represented by the following formula:

[0154] where R 32 represents a chain hydrocarbon group having 10 or more carbon atoms, s is 0 or 1, R 33 and / or R 34 represents a hydrogen atom, a hydrocarbon group, an alkanol group or an alkylamino group having 2 to 4 carbon atoms, and when s=0, R 33and R 34 Neither is a hydrogen atom or a hydrocarbon group.

[0155] Specific examples of suitable amines include monoalkyl (or alkenyl) amines such as tetradecylamine, stearylamine, oleylamine, tallow alkylamine, hardened tallow alkylamine, and soybean oil alkylamine; dialkyl (or alkenyl) amines such as N-tetradecylmethylamine, N-pentadecylmethylamine, N-hexadecylmethylamine, N-stearylmethylamine, N-oleylmethylamine, N-dodecyl(di)methylamine, N-tallow alkylmethylamine, N-hardened tallow alkylmethylamine, N-soybean oil alkylamine, ditetradecylamine, dipentadecylamine, dihexadecylamine , distearylamine, dioleylamine, N-cocoyl methylamine, dicocoylamine, bis(2-hexyldecyl)amine, bis(2-octyldodecyl)amine, bis(2-decyltetradecyl)amine, tallow dialkylamine, hardened tallow dialkylamine and soybean oil dialkylamine; and trialkyl(en)amines such as tetradecyldimethylamine, hexadecyldimethylamine, octadecyldimethylamine, tallow alkyldimethylamine, hardened tallow alkyldimethylamine, soybean oil alkyldimethylamine, dioleylmethylamine, tritetradecylamine, tristearylamine and trioleylamine. Suitable secondary amines have two alkyl (or alkenyl) groups having 14 to 18 carbon atoms.

[0156] Examples of compounds containing hexavalent molybdenum atoms include molybdenum trioxide or its hydrate (MoO3 nH2O), molybdic acid (H2MoO4), alkali metal molybdates (Q2MoO4) (wherein Q represents an alkali metal such as sodium and potassium), ammonium molybdate (e.g., (NH4)2MoO4 or heptamolybdate (NH4)6[Mo7O 24 ] 4H2O), MoOCl4, MoO2Cl2, MoO2Br2, Mo2O3Cl6, etc. Molybdenum trioxide or its hydrate, molybdic acid, alkali metal molybdates, and ammonium molybdate are generally suitable due to their availability. In one embodiment, the lubricating composition includes a molybdenum amine compound.

[0157] Other organo-molybdenum compounds can be the reaction product of a fatty oil, a monoalkylated alkylenediamine, and a molybdenum source. Such materials are generally prepared in two steps, a first step involving the preparation of an aminoamide / glyceride mixture at elevated temperature, and a second step involving the incorporation of the molybdenum.

[0158] Examples of fatty oils that can be used include cottonseed oil, peanut oil, coconut oil, linseed oil, palm kernel oil, olive oil, corn oil, palm oil, castor oil, rapeseed oil (low or high erucic acid), soybean oil, sunflower oil, menhaden oil, sardine oil, and tallow. These fatty oils are commonly referred to as glycerides, triacylglycerols, or triglycerides of fatty acids.

[0159] Examples of monoalkylated alkylenediamines that can be used include methylaminopropylamine, methylaminoethylamine, butylaminopropylamine, butylaminoethylamine, octylaminopropylamine, octylaminoethylamine, dodecylaminopropylamine, dodecylaminoethylamine, hexadecylaminopropylamine, hexadecylaminoethylamine, octadecylaminopropylamine, octadecylaminoethylamine, isopropyloxypropyl-1,3-diaminopropane, and octyloxypropyl-1,3-diaminopropane. Monoalkylated alkylenediamines derived from fatty acids can also be used. Examples include N-cocoalkyl-1,3-propylenediamine (Duomeen ® C), N-tall oil alkyl-1,3-propylene diamine (Duomeen ® T) and N-oleyl-1,3-propylenediamine (Duomeen ® O), all commercially available from Akzo Nobel.

[0160] The source of molybdenum for incorporation into the fatty oil / diamine complex is generally an oxygen-containing molybdenum compound similar to those described above, including ammonium molybdate, sodium molybdate, molybdenum oxide, and mixtures thereof. One suitable molybdenum source includes molybdenum trioxide (MoO3).

[0161] Commercially available nitrogen-containing molybdenum compounds include, for example, Sakura-lube available from Adeka ® 710 (which is a molybdenum amine compound) and Molyvan purchased from RT Vanderbilt ® 855.

[0162] When used, the nitrogen-containing molybdenum compound can comprise at least 0.001 wt %, or at least 0.002 wt %, or up to 2 wt %, or up to 1.0 wt % of the lubricating composition. When present, the molybdenum compound can provide at least 5 ppm, or at least 10 ppm, 5 ppm, or up to 300 ppm, or up to 800 ppm of platinum to the lubricant composition. In some embodiments, the lubricating composition contains less than 800 ppm of platinum, or less than 400 ppm, or less than 150 ppm, or less than 100 ppm, or less than 80 ppm, or less than 50 ppm, or less than 20 ppm, or less than 2 ppm, or less than 1 ppm of platinum, or 0 ppm.

[0163] In one embodiment, the molybdenum compound does not contain a dithiocarbamate moiety or ligand.

[0164] The lubricating composition may include a platinum compound in an amount that provides 40 wt ppm to 1200 wt ppm, or at least 50 wt ppm, or at least 60 wt ppm, or at least 100 wt ppm, or at least 300 wt ppm, or at most 1000 wt ppm, or at most 800 wt ppm, or at most 500 wt ppm, or at most 400 wt ppm, or at most 250 wt ppm, or at most 200 wt ppm of platinum to the composition. The actual amount of the compound will depend in part on the nature and formula weight of the anion or complexing agent associated with the platinum, which can be readily calculated. In some embodiments, the platinum compound is present in the lubricating composition in an amount of 0 wt % to 1.1 wt %, or at least 0.01 wt %, or at least 0.02 wt %, or at least 0.03 wt %, or at least 0.04 wt %, or at least 0.07 wt %, or at most 0.5 wt %, or at most 0.35 wt %, or at most 0.2 wt %, or at most 0.18 wt %.

[0165] Additional deposit control additives

[0166] The lubricating composition may contain one or more deposit control additives selected from alkylaryl sulfonates, amine oxides, carboxylated alcohol ethoxylates, ethoxylated amines, ethoxylated amides, glycerides, glycol esters, imidazolines, lecithin, lecithin derivatives, lignin, monoglycerides, monoglyceride derivatives, olefin sulfonates, phosphate esters, phosphate ester derivatives, propoxylated fatty acids, ethoxylated fatty acids, propoxylated alcohols or alkylphenols, sucrose esters, dodecylbenzene or tridecylbenzene sulfonates, naphthalenesulfonates, petroleum sulfonates, tridecylbenzenesulfonic acid or dodecylbenzenesulfonic acid, sulfosuccinates, sulfosuccinate derivatives, or mixtures of two or more thereof, each of which compounds having a hydrocarbon group of at least about 8 carbon atoms.

[0167] For example, alkoxylated hydrocarbyl-substituted phenolic compounds such as propoxylated polyisobutylene phenol as described in WO 2014 / 193543 A1 may be used.

[0168] When present, the additional deposit control additive may be at least 0.01 wt%, or at least 0.10 wt%, or at least 0.5 wt%, or at most 6 wt%, or at most 3.0 wt%.

[0169] In some embodiments, no deposit control additives are used.

[0170] Demulsifier

[0171] Demulsifiers useful herein include trialkyl phosphates, and various polymers and copolymers of ethylene glycol, ethylene oxide, propylene oxide, and mixtures thereof. When present, the demulsifier may comprise at least 0.001%, or at least 0.01%, or at most 0.10% by weight of the lubricating composition.

[0172] Seal expansion agent

[0173] Seal swell agents useful herein include sulfolene derivatives such as Exxon Necton-37 ™ (FN1380) and Exxon Mineral Seal Oil ™ (FN 3200).

[0174] Example Lubricating Compositions

[0175] The engine lubricant may have a composition as shown in Table 1. All additives are expressed on an oil-free basis.

[0176] Table 1: Example Lubricating Compositions

[0177] Use of lubricating compositions

[0178] End uses of the lubricating compositions described herein include use as cylinder lubricants for internal combustion engines (e.g., for passenger cars, heavy-, medium-, or light-duty diesel vehicles, small engines such as motorcycles and three-stroke oil engines, and two-stroke marine diesel engines), but may also be used as engine oils, as driveline lubricants (including gear and automatic transmission oils), and in other industrial oils (such as hydraulic lubricants).

[0179] An exemplary method of lubricating a mechanical device, such as an engine of an automobile or truck, includes supplying an exemplary lubricating composition to the device.

[0180] Generally, a lubricating composition is added to the lubrication system of an internal combustion engine, which then delivers the lubricating composition to the cylinders of the engine during its operation, where small amounts can be ignited with fuel.

[0181] The internal combustion engine can be a diesel-fueled engine, a gasoline-fueled engine, a natural gas-fueled engine, a gasoline / alcohol-fueled engine, or a biodiesel-fueled engine. The internal combustion engine can be a 2-stroke engine or a 4-stroke engine.

[0182] In one embodiment, the engine is a heavy duty diesel engine.

[0183] The lubricating composition can be suitable for use as a cylinder lubricant regardless of the phosphorus or sulfated ash (ASTM D874-13a (2018)) content of the fuel.

[0184] Without intending to limit the scope of the exemplary embodiments, the following examples illustrate the preparation and evaluation of exemplary lubricating compositions.

[0185] Example

[0186] Obtain the following materials: Oil : 4-cSt Group III base oil, a hydrotreated heavy paraffinic petroleum distillate, sold as Yubase 4, available from SK Lubricants Co., Ltd.

[0187] 6-cSt Group III base oil, a hydrotreated heavy paraffinic petroleum distillate, sold as Yubase 6, available from SK Lubricants Co., Ltd.

[0188] Diluent oil, Class III.

[0189] The following components are expressed on an oil-free basis: antioxidants : Hindered phenol antioxidant (HPAO), Irganox ™ L 135, available from BASF (3,5-dibutyl-4-hydroxyphenyl) propionate).

[0190] Substituted diphenylamine (SDPA) antioxidant (nonylated diphenylamine) was obtained from Lubrizol.

[0191] Sulfurized organic compounds

[0192] As shown in Table 2, the sulfurized organic compounds designated AF were obtained from Lubrizol Corporation. Active sulfur was determined by ASTM D1662. Total sulfur was determined by ASTM D1552.

[0193] Table 2: Sulfurized organic compounds

[0194] dispersants

[0195] As shown in Table 3, the dispersants designated AF were obtained from Lubrizol Corporation.

[0196] Table 3: Dispersants

[0197] detergent

[0198] An overbased calcium salicylate detergent with a TBN of about 300 is available from Wuxi.

[0199] A magnesium sulfonate detergent having a TBN of about 690 was available from Lubrizol.

[0200] An overbased calcium sulfonate detergent having a TBN of about 170 is available from Lubrizol.

[0201] Viscosity regulator

[0202] Hydrogenated styrene obtained from Lubrizol b -Butadiene copolymer resin viscosity modifier, LZ 7418A.

[0203] An olefin copolymer resin viscosity modifier having an ethylene content of about 50% by weight was obtained from Lubrizol Corporation.

[0204] Dispersant viscosity modifier

[0205] Aromatic dispersant viscosity modifier A (reaction product of an olefin polymer containing carboxylic acid functional groups and 3-nitroaniline) available from Lubrizol.

[0206] Aromatic dispersant viscosity modifier B (amine functionalized aromatic maleic anhydride-styrene copolymer) available from Lubrizol.

[0207] Other additives

[0208] Secondary ZDDPs, a combination of primary and secondary ZDDPs derived from C3 and C6 alcohols.

[0209] Pour point depressant: Maleic anhydride / styrene copolymer available from Lubrizol.

[0210] Foam Suppressor: Mixture of polydimethylsiloxanes.

[0211] Propoxylated polyisobutylene phenol deposit control agent obtained by the reaction of propylene oxide with polyisobutylene phenol and KOH as described in WO2014193543A1.

[0212] Irgamet, a triazole derivative corrosion inhibitor available from BASF ™ 30 (N,N-bis(2-ethylhexyl)-1-triazole-1-methylamine).

[0213] Preparation of lubricating compositions

[0214] SAE-5-W30 viscosity grade engine lubricant formulations suitable for heavy duty diesel engines prepared in a Group III base oil of lubricating viscosity containing the sulfurized olefins described herein were prepared according to the formulations shown in Tables 3, 4 and 5.

[0215] The weight % of all ingredients (except oil) are expressed as active (oil-free) basis.

[0216] In Table 4, Example 1 contains both a hindered phenol antioxidant (HPAO) and a substituted diphenylamine (SDPA) antioxidant, while Example 2 has essentially the same formulation as Example 1, except that only the hindered phenol antioxidant is used, with the amount increased to maintain the same total amount of antioxidants.

[0217] Table 4: Lubricating composition formulations Theoretical values ​​based on composition A series of engine lubricants suitable for heavy-duty diesel engines were prepared in a Group III base oil of lubricating viscosity containing sulfurized olefin B as described above and an amine-free antioxidant, along with a polymeric viscosity modifier, an ashless succinimide dispersant, an overbased detergent, an antioxidant, zinc dialkyldithiophosphate (ZDDP), and other performance additives, as shown in Table 5. In these examples, varying amounts of phenolic antioxidant were used.

[0218] Table 5: Lubricating composition formulations Theoretical values ​​based on composition A series of engine lubricants suitable for use in heavy-duty diesel engines prepared in a Group III base oil of lubricating viscosity containing various sulfurized olefins are shown in Table 6. The amount of sulfurized olefin was adjusted to provide approximately the same total amount of sulfur.

[0219] Table 6 Theoretical values ​​based on composition Evaluation of lubricating compositions The lubricating compositions of the above examples were subjected to various tests: Total Base Number (TBN) : Measured according to ASTM D2896-21.

[0220] Kinematic viscosity: The kinematic viscosity at 100°C (KV_100) and the kinematic viscosity at 40°C (KV_40) were measured according to ASTM D445-21e1.

[0221] Sulfated ash % (SA%) : Measured according to ASTM D874-13a.

[0222] Viscosity Index : Measured according to ASTM D2270-10 (2016) “Standard Practice for Calculating Viscosity Index from Kinematic Viscosity at 40°C and 100°C”.

[0223] Apparent viscosity : Determined by the following method: 1. Measured in cP using a Cold-Cranking Simulator (CCS) at -30°C according to ASTM D5293-20, “Standard Test Method for Apparent Viscosity of Engine Oils and Base Stocks Between –10°C and –35°C Using a Cold-Cranking Simulator.”

[0224] 2. ASTM D5481-21 “Standard Test Method for Measuring Apparent Viscosity at High-Temperature and High-Shear Rate by Multicell Capillary Viscometer” (HTHS), units are cP.

[0225] 3. For some embodiments, CEC L-36-90 “High shear high temperature viscosity measurement”, 2019.

[0226] Antioxidant properties

[0227] Oxidation performance was determined using the Renault Catalyst Oxidation Test (TOC-4) procedure from Renault (RNES-B-00023). This test method evaluates the oxidation resistance of engine lubricating oil compositions and simulates the harsh conditions of engine oils subjected to increased loads and conditions, as well as the variability of a thermowell. In the TOC-4 procedure, four tubes (each containing 150 g of oil containing an anhydrous iron(III) acetylacetonate catalyst (360 ppm iron)) were heated in a test cell at 170°C for 168 hours. During this time, air was blown through the oil in the tubes at a rate of 10 liters / hour. Samples (30 ml) of each oil were evaluated for oxidative degradation after 24, 120, 136, and 168 hours; the 120-hour sample provides the average value for the TOC-4 procedure. Infrared spectroscopy is used to assess the oxidative degradation of oil samples by measuring the area of ​​the infrared band between 1800 cm⁻¹ and 1650 cm⁻¹ (C=O) and comparing the increase in this band's area to that of the original oil (sample at t=0). A lower peak area increase indicates less oxidative degradation. To pass the TOC-4 test, the peak area increase after 120 hours must be less than 400.

[0228] Total Acid Number (TAN) (mg KOH / g) at 120 hours according to ASTM D664-18e2 “Standard Test Method for Acid Number of Petroleum Products by Potentiometric Titration”.

[0229] Antioxidant properties : Determined by the change in kinematic viscosity at 170°C for the following: 1. Relative change in KV_40 at 120 hours compared to the fresh lubricating composition, % (≤ 200 to meet Renault RN-17 specification).

[0230] 2. Relative change in KV_100 at a specified time (eg, 120 hours or 260 hours) compared to the fresh lubricating composition, %.

[0231] Oxidative stabilityVolvo T-13 Test: Measured according to ASTM D8048-21ae1, "Standard Test Method for Evaluation of Diesel Engine Oils in T-13 Diesel Engines," using a 2010 Volvo / Mack D13 / D8, 505 bhp, 13L inline 6-cylinder diesel engine with 6 electronic unit injectors, a variable geometry turbocharger, and cooled exhaust gas recirculation (EGR). This test evaluates the oxidative stability of an engine oil at a given fuel flow rate, running at 1500 RPM steady-state conditions for 360 hours, generating approximately 2200 Nm, an oil temperature of 130°C, and 19%-20% EGR.

[0232] Oxidation induction time OIT (Oxidation Intensity Test): Oxidation resistance of a film is measured in minutes as OIT, which is determined according to CECL-85-99: "Oxidative Stability of Lubricants by PDSC (Pressure Differential Scanning Calorimetry)." This represents the time after which oxygen uptake, as measured by pressure drop, ceases. The longer the OIT, the better the oxidation resistance.

[0233] Sediment control Deposit control was evaluated using the following MHT TEOST and Komatsu hot tube tests.

[0234] MHT TEOST Measured according to ASTM D7097-19, “Standard Test Method for Determination of Moderately High Temperature Piston Deposits by Thermo-Oxidation Engine Oil Simulation Test—TEOST MHT.” Total deposits are reported in mg.

[0235] Komatsu heat pipe test (280°C), KES_07.803: In this test, a glass tube is inserted into and heated by an aluminum heater block. The sample is pumped through a syringe pump at 0.31 cm 3 / hour flow rate together with 10cm3 At the end of the test, the tubes were rinsed and visually rated on a scale of 0 to 10, with 0 being a black tube and 10 being a clean tube.

[0236] Corrosion performance

[0237] Corrosion performance was evaluated according to ASTM D6594-20e1, "Standard Test Method for Evaluation of Diesel Engine Oil at 135°C" and ASTM D130-19, "Standard Test Method for Corrosiveness to Copper from Petroleum Products by Copper Strip Test." The ASTM D6594 test method covers testing diesel engine lubricants to determine their propensity to corrode various metals, particularly lead and copper alloys commonly used in cam followers and bearings.

[0238] Table 7 shows the results of the Volvo T-13 test for Example 1 and Example 2.

[0239] Table 7: Oxidative Stability

[0240] This test is a rigorous heavy-duty oxidation engine test. The lubricating composition of Example 2 showed excellent control of oxidation and viscosity increase, exceeding the required industry limits for this test. This result was unexpected considering the absence of an aminic antioxidant.

[0241] Additional test results for Examples 1-7 are shown in Table 8.

[0242] Table 8: Test results Too sticky to measure A lower peak area increase indicates lower oxidative degradation.

[0243] The results show that increasing the amount of phenolic antioxidant leads to improved oxidation resistance (e.g., oxidation induction time). At 4 wt.% phenolic antioxidant, the oxidation resistance is comparable to that of the composition containing SDPA. Examples 6 and 7 provide excellent oxidation performance and viscosity.

[0244] Table 9 shows the results of oxidation induction time of Examples 8 to 13.

[0245] Table 9: Oxidation induction time

[0246] The corrosion test results are shown in Table 10.

[0247] Table 10: Corrosion test results

[0248] As can be seen from Tables 9 and 10, Examples 9 and 10 provide excellent oxidation performance while also providing reduced metal corrosion.

[0249] Example 13 utilizes a sulfurized fatty acid ester of the type described in U.S. Patent No. 11,136,652 B1. Example 13 performs inferior to Examples 8, 9, and 10, which exhibit excellent oxidation performance. These three samples contain less than 0.015% active sulfur by weight of the lubricating composition and sulfurized olefins in which the amount of active sulfur is less than 20% by weight of the total sulfur in the sulfurized olefin.

[0250] The results show that relatively high levels (2 to 4 wt%) of SDPA-free phenolic antioxidants can achieve the desired oxidation performance previously relied upon for SDPA-based phenolic antioxidants, while also providing lower corrosion rates.

[0251] Each file mentioned above is incorporated herein by reference.Unless in the examples or otherwise clearly stated, all numerical values ​​for the amount of substance, reaction conditions, molecular weight, number of carbon atoms, etc., in this specification sheet should be understood to be modified by the word "about".Unless otherwise stated, each chemical or composition mentioned herein should be interpreted as commercial grade material, which may contain isomers, by-products, derivatives, and other such materials generally understood to be present in commercial grade. However, unless otherwise stated, the amount of each chemical component does not include any solvent or diluent oil, which may be present in commercial material generally. It should be understood that the upper and lower limits of amount, range, and ratio as described herein may be independently combined.Similarly, the scope and amount of each element of the present invention may be used together with the scope or amount of any other element.

[0252] The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

[0253] It will be appreciated that variations of the above-disclosed and other features and functions, or alternatives thereof, may be combined into many other different systems or applications, wherein various currently unforeseen or unanticipated alternatives, modifications, variations, or improvements may be subsequently made by those skilled in the art and are intended to be encompassed by the appended claims.

Claims

1. A lubricating composition comprising: oil of lubricating viscosity; phenolic antioxidants; Sulfurized organic compounds containing not more than 8% by weight of active sulfur; Optionally, one or more performance additives selected from the group consisting of: Succinimide dispersant, and Detergent.

2. The lubricating composition of claim 1, wherein the lubricating composition is at least substantially free of substituted diphenylamine (SDPA) antioxidants.

3. The lubricating composition according to any preceding claim, wherein the lubricating composition is at least substantially free of aminic antioxidants.

4. The lubricating composition of any preceding claim, wherein the phenolic antioxidant comprises at least 0.1 wt%, or at least 0.5 wt%, or at least 1 wt%, or at least 1.5 wt%, or at least 2 wt% of the lubricating composition.

5. The lubricating composition of any preceding claim, wherein the phenolic antioxidant comprises no more than 8 wt%, or no more than 6 wt%, or no more than 5 wt%, or no more than 4 wt%, or no more than 3 wt% of the lubricating composition.

6. The lubricating composition of any preceding claim, wherein the phenolic antioxidant is selected from the group consisting of hindered phenols, hindered alkylphenol esters, hindered alkoxyphenols, hindered phenol acetates, hindered bisphenols, polyphenols, 4-tert-butylphenol-formaldehyde condensates, 4-tert-butylphenol-acetaldehyde condensates, and mixtures thereof.

7. The lubricating composition according to any preceding claim, wherein the phenolic antioxidant is selected from the group consisting of: A mixture of C7-C9 branched alkyl esters of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionic acid; C4 alkyl esters of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionic acid, and 2,2'-Thiodiethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

8. The lubricating composition of any preceding claim, wherein the sulfurized organic compound has an active sulfur content of no more than 8 weight percent, or no more than 6 weight percent, or no more than 5 weight percent, or no more than 4.0 weight percent, or no more than 3 weight percent, or no more than 2.5 weight percent, or no more than 2 weight percent.

9. The composition of any preceding claim, wherein the sulfurized organic compound has a total sulfur content of at least 1 wt%, or at least 1.5 wt%, or at least 2 wt%, or no more than 18 wt%, or no more than 15 wt%, or no more than 14.0 wt%, or no more than 12.0 wt%, or no more than 5 wt%.

10. A lubricating composition according to any preceding claim, wherein the sulphurised organic compound provides at least 0.01 wt%, or at least 0.03 wt%, or at least 0.05 wt%, or at most 0.12 wt%, or at most 0.09 wt%, or at most 0.07 wt% sulphur to the lubricating composition.

11. A lubricating composition according to any preceding claim, wherein the sulphurised organic compound provides no more than 0.04 wt% active sulphur, or no more than 0.03 wt%, or no more than 0.025 wt%, or no more than 0.02 wt% active sulphur to the lubricating composition.

12. A lubricating composition according to any preceding claim, wherein the sulphurised organic compound comprises at least 0.1 wt%, or at least 0.15 wt%, or at least 0.2 wt% of the lubricating composition.

13. A lubricating composition according to any preceding claim, wherein the sulphurised organic compound comprises at most 1 wt%, or at most 0.8 wt%, or at most 0.7 wt%, at most 0.6 wt%, or at most 0.5 wt% of the lubricating composition.

14. The lubricating composition of any preceding claim, wherein active sulfur comprises no more than 25 weight percent, or no more than 22 weight percent, or no more than 20 weight percent, or no more than 19 weight percent of the total sulfur in the sulfurized organic compound, or at least 1 weight percent, or at least 1.5 weight percent, or at least 6 weight percent of the total sulfur in the sulfurized organic compound.

15. The lubricating composition of any preceding claim, wherein the sulfurized organic compound is selected from the group consisting of oligomeric polysulfides, alkyl polysulfides, sulfurized esters, sulfurized alicyclic dialkyl esters, sulfurized alicyclic diene esters, and mixtures thereof.

16. A lubricating composition according to any preceding claim, wherein the sulphurised organic compound comprises an oligomeric polysulphide or a mixture thereof.

17. The lubricating composition of claim 16, wherein the oligomeric polysulfide or mixture thereof has Formula I: R 1 ―S x ―[(C(R’) v H 2-v ) n ―S x ] p ―R 2 Formula I, where R 1 and R 2 Each is independently a C2-C20 alkyl group; Each n is independently at least 1; p is at least 1; Each v is 0-2; and Each x is independently at least 1.

18. The lubricating composition of claim 16, wherein the oligomeric polysulfide or mixture thereof has a total sulfur content of at least 5 wt.% and / or at most 45 wt.% and an active sulfur content of at least 0.5 wt.% and / or at most 10 wt.%.

19. A lubricating composition according to any preceding claim, wherein the sulphurised organic compound comprises an alkyl polysulphide or a mixture thereof.

20. The lubricating composition of claim 19, wherein the alkyl polysulfide or mixture thereof has Formula II: R 1 ―S x ―R 2 Formula II, where R 1 and R 2 are each independently a C2-C20 alkyl group; and Each x is independently at least 1.

21. The lubricating composition of claim 19 or 20, wherein the alkyl polysulfide or mixture thereof has a total sulfur content of at least 5 wt.% and / or at most 20 wt.% and an active sulfur content of at least 0.5 wt.% and / or at most 45 wt.%.

22. A lubricating composition according to any preceding claim, wherein the sulphurised organic compound comprises a sulphurised fatty acid ester of a fatty alcohol.

23. The lubricating composition of claim 22, wherein the sulfurized organic compound comprises a sulfurized triglyceride or a mixture thereof.

24. The lubricating composition of claim 23, wherein the sulfurized triglyceride or mixture thereof has formula III: CH2―O―C(=O)―R 3 │ CH2―O―C(=O)―R 4 │ CH2―O―C(=O)―R 5 Formula III, where R 3 、R 4 and R 5 are each independently a C8 or higher alkyl or alkenyl group, or a C10 or higher alkyl or alkenyl group, or up to a C30 or up to a C24 alkyl or alkenyl group; and where R 3 、R 4 and R 5 At least one of them is connected to the sulfur atom of the sulfur-containing portion, the middle end of the alkyl group.

25. The lubricating composition of claim 23 or 24, wherein the sulfurized triglyceride or mixture thereof has a total sulfur content of at least 5% by weight and / or at most 15% by weight and an active sulfur content of less than 5% by weight.

26. The lubricating composition of any preceding claim, wherein the sulfurized organic compound comprises at least one of a cycloaliphatic dialkyl ester, a cycloaliphatic diene ester, and mixtures thereof.

27. The lubricating composition of claim 26, wherein the at least one of the cycloaliphatic dialkyl ester, the cycloaliphatic diene ester, and mixtures thereof has Formula V: Formula V, where R 13 and R 14 Each of is independently a C2 or higher alkyl or alkenyl group; and x is at least 1.

28. The lubricating composition of claim 26 or 27, wherein the at least one of the cycloaliphatic dialkyl ester, the cycloaliphatic diene ester and mixtures thereof has a total sulfur content of at least 5 wt.% and / or at most 15 wt.% and an active sulfur content of at least 1 wt.% and / or at most 5 wt.%.

29. The lubricating composition of any preceding claim, wherein the succinimide dispersant comprises at least 0.2 wt%, or at least 0.5 wt%, or at least 1.0 wt%, or at most 7.0 wt%, or at most 6.0 wt% of the lubricating composition.

30. The lubricating composition of any preceding claim, wherein the succinimide dispersant provides no more than 0.1 wt% nitrogen to the lubricating composition.

31. The lubricating composition of any preceding claim, wherein the detergent comprises at least 0.1 wt%, or at least 0.2 wt%, or at least 0.25 wt%, or at least 0.4 wt%, or at most 3.0 wt%, or at most 2.0 wt%, or at most 1.5 wt%, or at most 1.25 wt% of the lubricating composition.

32. The lubricating composition of any preceding claim, wherein the detergent provides at least 0.005 wt% boron, or at least 0.03 wt% boron, or at most 0.06 wt%, or at most 0.04 wt% boron to the lubricating composition.

33. A lubricating composition according to any preceding claim, wherein the detergent provides at least 0.04 wt%, or at least 0.08 wt%, or at most 0.4 wt%, or at most 0.3 wt% calcium to the lubricating composition.

34. The lubricating composition of any preceding claim, wherein the detergent is selected from the group consisting of alkaline earth metal sulfonates, alkaline earth metal salicylates, alkaline earth metal salicylins, alkaline earth metal salicyl alkoxides, alkaline earth metal hydrocarbyl-substituted hydroxybenzoates, and mixtures thereof.

35. The lubricating composition of any preceding claim, wherein the oil of lubricating viscosity comprises at least 80 wt% of the lubricating composition, or at most 94 wt% of the lubricating composition.

36. The lubricating composition of any preceding claim, further comprising at least one of the group consisting of an antiwear agent, a corrosion inhibitor, a viscosity modifier, a pour point depressant, a defoamer, an extreme pressure agent, a friction modifier, a viscosity modifier, and combinations thereof.

37. The lubricating composition of claim 36, wherein the antiwear agent provides 300 ppm to 850 ppm by weight of phosphorus to the lubricating composition, based on the total weight of the lubricating composition.

38. The lubricating composition of claim 36, wherein the viscosity modifier comprises a dispersant viscosity modifier comprising at least one of: the reaction product of an olefin polymer containing carboxylic acid functional groups and 3-nitroaniline; and Amine functionalized aromatic maleic anhydride-styrene copolymers.

39. The lubricating composition of claim 38, wherein the dispersant viscosity modifier comprises at least 0.01 wt%, or at least 0.1 wt%, or at least 2 wt%, or no more than 8 wt%, or no more than 7 wt% of the lubricating composition.

40. The lubricating composition of claim 36, wherein the viscosity modifier comprises hydrogenated styrene- b - At least one of a butadiene copolymer resin viscosity modifier and an olefin copolymer resin viscosity modifier.

41. The lubricating composition of any preceding claim, wherein the molybdenum content is no more than 800 ppm, or no more than 400 ppm, or no more than 150 ppm, or no more than 100 ppm, or no more than 80 ppm, or no more than 50 ppm, or no more than 20 ppm, based on the total weight of the lubricating composition.

42. A method for improving the oxidation stability of a lubricating oil in an engine, the method comprising supplying to the engine a lubricating composition according to any preceding claim.

43. The method of claim 42, wherein when the engine is a Volvo T-13 engine and is run for 360 hours, the kinematic viscosity at 40°C (KV_40) increases from 300 hours to 360 hours is less than 75 or less than 50, and / or the oxidation at the end of the test is less than 125 A / cm, as measured by IR peak height.

44. Use of a lubricating composition according to any one of claims 1 to 41 for lubricating an engine.

45. A lubricating composition comprising: a sulfurized organic compound sufficient to provide at least 0.1 weight percent sulfur in the lubricating composition; at least 0.1% by weight of a phenolic antioxidant; at least 0.1% by weight of detergent; and at least 2% by weight of a dispersant; The lubricating composition contains no more than 0.04 wt % of active sulfur.

46. ​​The lubricating composition of claim 45, wherein the detergent comprises: at least one of a calcium salicylate detergent and a calcium sulfonate detergent sufficient to provide at least 0.1% or at least 0.12% by weight calcium to the lubricating composition; Sufficient magnesium sulfonate detergent to provide at least 0.02 wt. % or at least 0.04 wt. % magnesium to the lubricating composition.

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