Method of reducing lead corrosion in internal combustion engines

Abstract

The present disclosure describes a lubricant composition effective to reduce lead corrosion by at least including a blend of lubricant additives having a base oil of lubricating viscosity, a dispersant, a friction modifier, and a boron-containing compound.

Description

Technical Field

[0001] This disclosure generally relates to lubricating oil compositions and additives thereof, as well as methods for reducing lead corrosion. Background Technology

[0002] Lubricants intended for use as motor oils (also commonly referred to as engine oils or crankcase oils) in gasoline or diesel automotive engines typically consist of a base oil, or a blend of a base oil with a lubricating viscosity, and one or more additives to meet certain performance requirements of the intended application. Modern industry standards impose increasingly stringent requirements on the composition and performance of such oils, often leaving very little room for flexibility in lubricant formulation. As lubricant manufacturers strive to meet a variety of industry standards, achieving all the required performance and industry standards cost-effectively becomes a challenge. While lubricants typically include various additive blends to achieve the desired performance for each application, improving performance with complex additive mixtures is often challenging because a particular additive that improves one performance benefit often adversely affects other desired benefits of the lubricant.

[0003] For example, friction modifiers are a class of lubricant additives that are typically used to improve the ability of lubricants to reduce friction and / or wear, which generally leads to improved fuel economy. A common type of friction modifier is a nitrogen-free organic friction modifier with carboxylic acid and / or hydroxyl groups. While such friction modifiers are beneficial additives that provide improved friction and wear, they also tend to be associated with an undesirable increase in lead corrosion. Lead corrosion in cases using such friction modifiers appears to be directly related to the treatment rate of the friction modifier, as increasing the amount of friction modifier results in a corresponding increase in lead corrosion. Summary of the Invention

[0004] According to one embodiment, this document describes a method for reducing lead corrosion in an internal combustion engine lubricated with a lubricating oil composition. In one aspect, the method includes supplying a lubricating oil composition to the internal combustion engine, the lubricating oil composition comprising a hydrocarbon-substituted acylating agent obtained by reacting a hydrocarbon-substituted succinimide dispersant with a nitrogen source, a nitrogen-free organic friction modifier having carboxylic acid and / or hydroxyl groups, and a major amount of a base oil or base oil blend having a lubricating viscosity. The lubricating oil composition includes a blend of boron-containing compounds selected from boric acid or boronic acid.

[0005] In other embodiments, the method described in the preceding paragraph may be combined with optional features and steps in any combination thereof. These optional features and / or steps include one or more of the following: wherein the nitrogen-free organic friction modifier has side hydroxyl groups obtained from the reaction of fatty acids with alkanols; and / or wherein the lubricating oil composition contains about 250 ppm to about 350 ppm of boron provided by a boron-containing compound per 1 wt% of nitrogen-free organic friction modifier; and / or wherein the lubricating oil composition exhibits no more than about 500 ppm of lead corrosion per 1 wt% of nitrogen-free organic friction modifier, as per ASTM. The measurement is as per D6594; and / or the alkyl-substituted succinimide dispersant is boronized from a boron source separate from the boron-containing compound; and / or the boron-containing compound has the structure XB-(OH)2, wherein X is a hydroxyl group, a straight-chain or branched alkyl group, a cyclic alkyl group, one or more aryl groups, a benzofuranyl group, a dibenzofuranyl group, or a combination thereof; and / or the boron-containing compound is borous acid, wherein X is a straight-chain or branched C1 to C10 group, one or more aryl groups, a benzofuranyl group, a dibenzofuranyl group. Or a combination thereof; and / or said nitrogen-free organic friction modifier comprises a blend of monoesters and diesters of fatty acids; and / or said nitrogen-free organic friction modifier comprises a blend of monoesters and diesters of oleic acid; and / or said nitrogen-free organic friction modifier comprises glyceryl monooleate; and / or said lubricating oil composition comprises about 100 ppm to about 300 ppm of boron provided by said boron compound, up to about 10 wt% of said hydrocarbon-substituted succinimide dispersant and up to about 1 wt% of said nitrogen-free organic friction modifier.

[0006] In another embodiment or method, this document describes a lubricating oil composition for reducing lead corrosion in internal combustion engines. In various aspects of this embodiment, the lubricating oil composition comprises at least the following blends: a hydrocarbon-substituted succinimide dispersant obtained by reacting a hydrocarbon-substituted acylated agent with a nitrogen source; a nitrogen-free organic friction modifier having carboxylic acid and / or hydroxyl groups; a boron-containing compound selected from boric acid or borous acid; and a major amount of a base oil or base oil blend having a lubricating viscosity.

[0007] In other embodiments, the composition described in the preceding paragraph may be combined with optional features and limitations in any combination thereof. These optional features and / or limitations include one or more of the following: wherein the nitrogen-free organic friction modifier has side hydroxyl groups obtained from the reaction of fatty acids with alkanols; and / or wherein the lubricating oil composition contains about 250 ppm to about 350 ppm of boron provided by a boron-containing compound per 1 wt% of nitrogen-free organic friction modifier; and / or wherein the lubricating oil composition exhibits no more than about 500 ppm of lead corrosion per 1 wt% of nitrogen-free organic friction modifier, as per ASTM. The measurement was taken by D6594; and / or the alkyl-substituted succinimide dispersant is boronized from a boron source separated from the boron-containing compound; and / or the boron-containing compound has the structure XB-(OH)2, wherein X is a hydroxyl group, a straight-chain or branched alkyl group, a cyclic alkyl group, one or more aryl groups, a benzofuranyl group, a dibenzofuranyl group, or a combination thereof; and / or the boron-containing compound is borous acid, wherein X is a straight-chain or branched C1 to C10 group, one or more aryl groups, a benzofuranyl group, a dibenzofuranyl group, or a combination thereof; and / or The nitrogen-free organic friction modifier comprises a blend of monoesters and diesters of fatty acids; and / or the nitrogen-free organic friction modifier comprises a blend of monoesters and diesters of oleic acid; and / or the nitrogen-free organic friction modifier comprises glyceryl monooleate; and / or the lubricating oil composition comprises about 100 ppm to about 300 ppm of boron provided by the boron-containing compound, up to about 10 wt% of the hydrocarbon-substituted succinimide dispersant, and up to about 1 wt% of the nitrogen-free organic friction modifier; and / or the lubricating oil composition is a bus electric motor oil.

[0008] In yet another embodiment or method, the use of a lubricating oil composition for reducing lead corrosion in an internal combustion engine is described herein. In various aspects of this embodiment, the use of the lubricating oil composition includes the use of at least the following blends: a hydrocarbon-substituted succinimide dispersant obtained by reacting a hydrocarbon-substituted acylation agent with a nitrogen source; a nitrogen-free organic friction modifier having carboxylic acid and / or hydroxyl groups; a boron-containing compound selected from boric acid or borous acid; and a major amount of a base oil or base oil blend having a lubricating viscosity to reduce lead corrosion in an internal combustion engine. Additionally, the use of the lubricating oil composition may also include any other embodiments as described in this summary.

[0009] The following terminology definitions are provided to clarify the meaning of certain terms as used herein.

[0010] The terms “oil composition,” “lubricating composition,” “lubricating oil composition,” “lubricating oil,” “lubricant composition,” “lubricating compound,” “fully formulated lubricant composition,” “lubricant,” “crankcase oil,” “crankcase lubricant,” “engine oil,” “engine lubricant,” “electric motor oil,” and “electric motor lubricant” are considered to be completely interchangeable synonyms and refer to finished lubricating products that contain a large amount of base oil plus a small amount of additives.

[0011] As used herein, the terms “additive package,” “additive concentrate,” “additive composition,” “engine oil additive package,” “engine oil additive concentrate,” “crankcase additive package,” “crankcase additive concentrate,” “electric motor oil additive package,” and “electric motor oil concentrate” are considered fully interchangeable synonyms and refer to the portion of a lubricating oil composition that excludes a significant amount of the base oil feedstock mixture. Additive packages may or may not include viscosity index improvers or pour point depressants.

[0012] As used in this article, “lead corrosion” refers to the change in lead concentration of the lubricant during an evaluation conducted according to ASTM D6594. Lead concentration can be measured by ICP according to ASTM D5185.

[0013] The term "highly basic" refers to metal salts, such as sulfonates, carboxylates, salicylates, and / or phenolates, in which the metal content exceeds the stoichiometric amount. These salts can have conversion levels exceeding 100% (i.e., they can contain more than 100% of the theoretical amount of metal required to convert the acid to its "normal," "neutral" salt). The expression "metal ratio," often abbreviated as MR, is used to represent the ratio of the total stoichiometric amount of metal in a highly basic salt to the stoichiometric amount of metal in a neutral salt, based on known chemical reactivity and stoichiometry. In normal or neutral salts, the metal ratio is one, while in highly basic salts, MR is greater than one. These are often referred to as highly basic, super-basic, or extremely basic salts and can be salts of organic sulfuric acids, carboxylic acids, salicylic acids, sulfonic acids, and / or phenols.

[0014] The term "alkaline earth metals" refers to calcium, barium, magnesium, and strontium, while the term "alkali metals" refers to lithium, sodium, potassium, rubidium, and cesium.

[0015] As used herein, the terms "hydrocarbon group" or "hydrocarbon substituent" or "hydrocarbon substituent" are used in their ordinary sense, as is well known to those skilled in the art. Specifically, it refers to a group having carbon atoms directly connected to the remainder of the molecule and having predominantly hydrocarbon characteristics. Each hydrocarbon group is independently selected from hydrocarbon substituents and hydrocarbon substituents containing one or more halogen groups, hydroxyl groups, alkoxy groups, mercapto groups, nitro groups, nitroso groups, amino groups, pyridyl groups, furanyl groups, imidazole groups, oxygen and nitrogen substitutions, and wherein no more than two non-hydrocarbon substituents are present for every ten carbon atoms in the hydrocarbon group.

[0016] As used herein, the term "hydroalkyl substituent" or "hydroalkyl group" is used in its usual sense, as is well known to those skilled in the art. Specifically, it refers to a group that is directly attached to the remainder of a molecule by two carbon atoms at two positions and is predominantly hydrocarbon-characteristic. Each hydroalkyl group is independently selected from divalent hydrocarbon substituents and contains substituted divalent hydrocarbon substituents such as: halogen groups, alkyl groups, aryl groups, alkylaryl groups, aralkyl groups, hydroxyl groups, alkoxy groups, mercapto groups, nitro groups, nitroso groups, amino groups, pyridyl groups, furanyl groups, imidazolyl groups, oxygen, and nitrogen, and wherein no more than two non-hydrocarbon substituents are present for every ten carbon atoms in the hydroalkyl group.

[0017] Unless otherwise expressly stated, as used herein, the term "percentage by weight" means the percentage of the said component by weight of the whole composition.

[0018] As used herein, the terms “soluble,” “oil-soluble,” or “dispersible” may, but do not necessarily, mean that a compound or additive is soluble, miscible, or capable of being suspended in oil in all proportions. However, the foregoing terms do mean that they are, for example, soluble, suspended, dispersible, or stably dispersed in oil to a degree sufficient to exert their intended effect in an environment where oil is used. Furthermore, the addition of other additives may be permitted, if desired, at higher concentrations of a particular additive.

[0019] The term “TBN” as used in this document refers to the total base number, expressed in mg KOH / g, as measured by the method of ASTM D2896.

[0020] As used herein, the term "alkyl" refers to a straight-chain, branched, cyclic, and / or substituted saturated chain moiety having about 1 to about 100 carbon atoms. The term "alkenyl" as used herein refers to a straight-chain, branched, cyclic, and / or substituted unsaturated chain moiety having about 3 to about 10 carbon atoms. The term "aryl" as used herein refers to monocyclic and polycyclic aromatic compounds, which may include alkyl, alkenyl, alkylaryl, amino, hydroxyl, alkoxy, halogen substituents, and / or heteroatoms, including but not limited to nitrogen, oxygen, and sulfur.

[0021] The molecular weight of any embodiment described herein can be determined using instruments such as gel permeation chromatography (GPC) instruments available from Waters, and the data processed using software such as Waters Empower software. The GPC instrument may be equipped with a Waters separation module and a Waters refractive index detector (or similar optional equipment). GPC operating conditions may include a guard column, four Agilent PLgel columns (300 × 7.5 mm in length; 5 μm particle size, and pore size range of...). The column temperature is approximately 40 °C. Unstabilized HPLC-grade tetrahydrofuran (THF) can be used as a solvent at a flow rate of 1.0 mL / min. GPC instruments can be calibrated with commercially available polystyrene (PS) standards with a narrow molecular weight distribution ranging from 500 g / mol to 380,000 g / mol. For samples with a mass less than 500 g / mol, calibration curves can be extrapolated. Samples and PS standards can be dissolved in THF and prepared at concentrations from 0.1 to 0.5 wt%, and used without filtration. GPC measurements are also described in US 5,266,223, which is incorporated herein by reference. GPC methods also provide information on molecular weight distribution; see, for example, WWYau, JJ Kirkland, and DDBly, “Modern Size Exclusion Liquid Chromatography,” John Wiley and Sons, New York, 1979, which is also incorporated herein by reference.

[0022] The lubricants described herein are formulated for use in various types of lubricants, such as automotive lubricants and / or greases, internal combustion engine oils, hybrid engine oils, electric motor lubricants, transmission lubricants, gear oils, hydraulic lubricants, tractor hydraulic fluids, metal working fluids, turbine engine lubricants, stationary engine lubricants, tractor lubricants, motorcycle lubricants, power steering fluids, clutch fluids, shaft fluids, wet break fluids, etc. Suitable engine types may include, but are not limited to, heavy-duty diesel engines, bus engines, light-duty diesel engines, medium-speed diesel engines, or marine engines. Internal combustion engines may be diesel fuel engines, gasoline fuel engines, natural gas fuel engines, biofuel engines, hybrid diesel / biofuel engines, hybrid gasoline / biofuel engines, alcohol fuel engines, hybrid gasoline / alcohol fuel engines, compressed natural gas (CNG) fuel engines, or mixtures thereof. Diesel engines may be compression ignition engines. Gasoline engines may be spark ignition engines. Internal combustion engines may also be used in combination with electrical or battery power sources. Engines constructed in this way are often referred to as hybrid engines. Internal combustion engines may be 2-stroke, 4-stroke, or rotary engines. Suitable internal combustion engines include marine diesel engines (such as those for inland vessels), aircraft piston engines, low-load diesel engines, and engines for motorcycles, automobiles, locomotives, and trucks. Engines can be coupled with turbochargers.

[0023] Regardless of the sulfur, phosphorus, or sulfate ash (ASTM D-874) content, the internal combustion engine lubricant composition is suitable for any engine lubricant. The sulfur content of the engine oil lubricant can be about 1% by weight or less, or about 0.8% by weight or less, or about 0.5% by weight or less, or about 0.3% by weight or less, or about 0.2% by weight or less. In one embodiment, the sulfur content can range from about 0.001% by weight to about 0.5% by weight, or from about 0.01% by weight to about 0.3% by weight. The phosphorus content can be about 0.2% by weight or less, or about 0.1% by weight or less, or about 0.085% by weight or less, or about 0.08% by weight or less, or even about 0.06% by weight or less, about 0.055% by weight or less, or about 0.05% by weight or less. In one embodiment, the phosphorus content can be from about 50 ppm to about 1000 ppm, or from about 325 ppm to about 850 ppm. The total sulfate ash content may be about 2% by weight or less, or about 1.5% by weight or less, or about 1.1% by weight or less, or about 1% by weight or less, or about 0.8% by weight or less, or about 0.5% by weight or less. In one embodiment, the sulfate ash content may be about 0.05% by weight to about 0.9% by weight, or about 0.1% by weight or about 0.2% by weight to about 0.45% by weight. In another embodiment, the sulfur content may be about 0.4% by weight or less, the phosphorus content may be about 0.08% by weight or less, and the sulfate ash content may be about 1% by weight or less. In yet another embodiment, the sulfur content may be about 0.3% by weight or less, the phosphorus content may be about 0.05% by weight or less, and the sulfate ash content may be about 0.8% by weight or less.

[0024] Additionally, the lubricants described in this manual are suitable for meeting one or more industry specifications, such as ILSAC GF-3, GF-4, GF-5, GF-6, PC-11, CF, CF-4, CH-4, CK-4, FA-4, CJ-4, CI-4Plus, CI-4, API SG, SJ, SL, SM, SN, SN PLUS, ACEA A1 / B1, A2 / B2, A3 / B3, A3 / B4, A5 / B5, C1, C2, C3, C4, C5, E4 / E6 / E7 / E9, Euro 5 / 6, JASO DL-1, Low SAPS, Mid SAPS, or original equipment manufacturer (OEM) specifications, such as Dexos1. TM Dexos2 TM,MB-Approval 229.1, 229.3, 229.5, 229.51 / 229.31, 229.52, 229.6, 229.71, 226.5, 226.51, 228.0 / .1, 228.2 / .3, 228.31, 228.5, 228.51, 228.61, VW 501.01、502.00、503.00 / 503.01、504.00、505.00、505.01、506.00 / 506.01、507.00、508.00、509.00、508.88、509.99, BMW Longlife-01, Longlife-01FE, Longlife-04, Longlife-12FE, Longlife-14FE+, Longlife-17FE+, Porsche A40, C30, Peugeot Automobiles B71 2290, B712294, B71 2295, B71 2296, B71 2297, B712300, B71 2302, B71 2312, B71 2007, B71 2008, Renault RN0700, RN0710, RN0720, Ford WSS-M2C153-H, WSS-M2C930-A, WSS-M2C945-A, WSS-M2C913A, WSS-M2C913-B, WS S-M2C913-C, WSS-M2C913-D, WSS-M2C948-B, WSS-M2C948-A, GM6094-M, Chrysler MS-6395、Fiat 9.55535G1, G2, M2, N1, N2, Z2, S1, S2, S3, S4, T2, DS1, DSX, GH2, GS1, GSX, CR1, Jaguar Land Rover STJLR.03.5003, STJLR.03.5004, STJLR.03.5005, STJLR.03.5006, STJLR.03.5007, STJLR.51.5122, or any past or future PCMO or HDD specifications not mentioned herein. In some implementations, for passenger car engine oil (PCMO) applications, the phosphorus content in the finished fluid is 1000 ppm or less, or 900 ppm or less, or 800 ppm or less.

[0025] In one embodiment, the lubricating oil composition is an engine oil, wherein the lubricating oil composition may have (i) a sulfur content of about 0.5% by weight or less, (ii) a phosphorus content of about 0.1% by weight or less, and (iii) a sulfate ash content of about 1.5% by weight or less.

[0026] In one embodiment, the lubricating oil composition is suitable for a 2-stroke or 4-stroke marine diesel internal combustion engine. In one embodiment, the marine diesel internal combustion engine is a 2-stroke engine. In some embodiments, the lubricating oil composition is not suitable for a 2-stroke or 4-stroke marine diesel internal combustion engine for one or more reasons, including but not limited to the high sulfur content of the fuel used to power the marine engine and the high TBN (e.g., above about 40 TBN in marine engine oils) required for marine applications.

[0027] In some embodiments, the lubricating oil composition is suitable for engines powered by low-sulfur fuels, such as fuels containing about 1 to about 5% sulfur. Highway vehicle fuels contain about 15 ppm sulfur (or about 0.0015% sulfur).

[0028] Further details and advantages of this disclosure will be set forth in part in the following description and / or may be learned by practicing this disclosure. The details and advantages of this disclosure may be realized and obtained by means of the elements and combinations particularly pointed out in the appended claims. It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only, and do not limit the disclosure as claimed. Attached Figure Description

[0029] Figure 1 This is a graph showing lead corrosion of existing non-boronized friction modifiers, which demonstrates that lead corrosion increases with the corresponding increase in friction modifier treatment rate;

[0030] Figure 2 This is a graph comparing lead corrosion of a lubricant with a pre-boronized friction modifier with a lubricant blend containing a friction modifier, a dispersant, and a boron-containing compound;

[0031] Figure 3 This is a graph showing lead corrosion using various lubricant blends containing boron compounds compared to a control lubricant without friction modifiers; and

[0032] Figure 4 This is a graph showing the lead corrosion of each 1% weight percentage of friction modifier compared to existing non-boronized friction modifiers, showing the lubricant blend of the present invention. Detailed Implementation

[0033] Engine or crankcase lubricant compositions are commonly used in vehicles with spark-ignition and compression-ignition engines to provide reduced friction and other benefits. Such engines can be used in passenger cars or heavy-duty applications and include automobiles, trucks, motorcycles, and / or locomotive / train internal combustion engines to indicate only a few applications, and can operate on fuels including, but not limited to, gasoline, diesel, alcohols, biofuels, compressed natural gas, etc. These engines may include hybrid electric engines, which include both an internal combustion engine and electric or battery power; and / or advanced hybrid engines or internal combustion engines that include an automatic engine stop function when the vehicle is stationary. The methods and lubricant compositions described herein are effective in reducing lead corrosion in such engines.

[0034] In one method or embodiment, this disclosure describes methods and compositions that can effectively reduce lead corrosion in an internal combustion engine lubricated with a lubricating oil composition. In one aspect, the method includes supplying a lubricating oil composition or lubricant to an internal combustion engine, the lubricating oil composition or lubricant comprising at least (i) a hydrocarbon-substituted succinimide dispersant obtained by reacting a hydrocarbon-substituted acylated agent with a nitrogen source, (ii) a nitrogen-free organic friction modifier having carboxylic acid and / or hydroxyl groups and, in some methods, including side hydroxyl groups obtained by reacting fatty acids with alkanols, and (iii) a major amount of a base oil or base oil blend having a lubricating viscosity. The lubricating oil composition also comprises a boron-containing compound selected from boric acid or borous acid. In some methods, the friction modifier is not pre-reacted with the boron-containing compound or is not pre-boronized with the boron-containing compound; instead, the succinimide dispersant, the friction modifier, and the boron-containing compound are blended into the lubricating composition. Surprisingly, the amount of lead corrosion is improved in the method described herein when using blended components compared to lubricants containing a friction modifier that has been pre-reacted with a boron-containing compound before being added to the lubricant.

[0035] The method described herein involves supplying an engine with a lubricating oil composition having a hydrocarbon-substituted succinimide dispersant, a nitrogen-free organic friction modifier, and a boron-containing compound blend. Therefore, even more surprisingly, the blend described herein exhibits superior lead corrosion resistance compared to lubricating oil compositions containing a pre-boronized friction modifier.

[0036] Regarding the components, the methods and lubricating compositions described herein primarily include a dispersant that comprises at least a hydrocarbon-substituted succinimide dispersant, which can be obtained by reacting a hydrocarbon-substituted acylated agent with a nitrogen source (such as various polyalkylene polyamines discussed in more detail below).

[0037] In the method, the dispersant may include oil-soluble ashless dispersants selected from the group comprising or consisting of succinimide dispersants, succinate dispersants, and / or succinate-amide dispersants. In the method, the lubricating composition herein may contain up to about 10 weight percent of the dispersant herein, or about 1 weight percent to about 8 weight percent of the dispersant, and in other methods, about 2 weight percent to about 6 weight percent (or any other range within such endpoints).

[0038] Hydrocarbon dicarboxylic acids or anhydrides are reacted with a nitrogen source (such as a polyalkylene polyamine) to prepare succinimid dispersants. Succinimid dispersants and their preparation are disclosed in U.S. Patents 7,897,696 and 4,234,435, both of which are incorporated herein by reference. The hydrocarbon moiety of the hydrocarbon dicarboxylic acid or anhydride can be derived from polyolefin-based polymers, such as, but not limited to, butene polymers, for example, polymers of isobutylene. Polyisobutylenes suitable for use herein include those formed from conventional polyisobutylene or highly reactive polyisobutylene having a terminal vinylene content of at least about 60% (e.g., about 70% to about 90% and higher). Suitable polyisobutylenes may include those prepared using a BF3 catalyst.

[0039] The number-average molecular weight of the hydrocarbon substituents (such as polyisobutylene substituents) in the dispersant can vary over a wide range, for example, from about 500 to about 5,000 (in other methods, from about 1,000 to about 3,000, or from about 1,000 to about 2,000), as measured by gel permeation chromatography (GPC) using polystyrene (with a number-average molecular weight of 180 to about 18,000) as a calibration reference. The polyisobutylene portion of the dispersant preferably has a molecular weight distribution (MWD), also known as polydispersity, as determined by the ratio of weight-average molecular weight (Mw) to number-average molecular weight (Mn). Polymers with an Mw / Mn ratio less than about 2.2, preferably less than about 2.0, are most desirable. Suitable polyisobutylene substituents have a polydispersity of about 1.5 to about 2.1, or about 1.6 to about 1.8.

[0040] The dicarboxylic acid or anhydride of the dispersant can be selected from carboxylic acid reactants, such as maleic anhydride, maleic acid, fumaric acid, malic acid, tartaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, mesoconic acid, ethyl maleic anhydride, dimethyl maleic anhydride, ethyl maleic acid, dimethyl maleic acid, hexyl maleic acid, etc., including the corresponding acidic halides and C1-C4 aliphatic esters. The molar ratio of the dicarboxylic acid or anhydride to the hydrocarbon moiety in the reaction mixture used to prepare the hydrocarbon-dicarboxylic acid or anhydride can vary widely. Thus, the molar ratio can vary from about 5:1 to about 1:5 (e.g., from about 3:1 to about 1:3). A particularly suitable molar ratio of acid or anhydride to hydrocarbon moiety is from about 1:1 to about 2:1. Another useful molar ratio of dicarboxylic acid or anhydride to hydrocarbon moiety is from about 1.3:1 to about 1.8:1.

[0041] Any of many polyalkylene polyamines can be used as a dispersant additive in the preparation of the lubricants described herein. Non-limiting exemplary polyamines may include aminoguanidine bicarbonate (AGBC), diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), pentaethylenehexamine (PEHA), and heavy polyamines. Heavy polyamines may comprise mixtures of polyalkylene polyamines having small amounts of polyamine oligomers, such as TEPA and PEHA, but primarily oligomers having seven or more nitrogen atoms, two or more primary amines per molecule, and more extensive branching than conventional polyamine mixtures. Typically, these heavy polyamines have an average of 6.5 nitrogen atoms per molecule. Further non-limiting polyamines that can be used to prepare hydrocarbon-substituted succinimide dispersants are disclosed in U.S. Patent 6,548,458, the entire disclosure of which is incorporated herein by reference. The molar ratio of the hydrocarbon-dicarboxylic acid or anhydride to the polyalkylene polyamine may be from about 1:1 to about 3:1.

[0042] In one embodiment, the dispersant may be a reaction product of polyisobutylene succinic anhydride (PIBSA) and a polyamine (e.g., polyethyleneamine, such as tetraethylenepentamine, or various heavy polyamines). The dispersant described herein may have a molar ratio of polyisobutylene-substituted succinic anhydride to polyamine in the range of about 4:3 to about 1:10.

[0043] In some cases, the dispersants described herein may optionally be borated, phosphorylated, or post-reacted with various reagents such as maleic anhydride or a boron source different from the boron-containing compound also incorporated into the lubricant before being incorporated into the lubricant. These dispersants are typically the reaction product of at least one phosphorus compound, a boron compound, and / or maleic anhydride and at least one ashless dispersant as described above. If the dispersant is borated before being incorporated into the lubricant, it is borated with a boron compound or boron source different from the boron compound incorporated into the lubricant.

[0044] If used, suitable boron compounds that can be used for pre-reaction with the dispersants described herein include any boron compound or mixture of boron compounds capable of introducing boron-containing substances into an ashless dispersant. Any organic or inorganic boron compound capable of carrying out this reaction can be used. Therefore, boron oxide, boron oxide hydrate, boron trifluoride, boron tribromide, boron trichloride, HBF4 boron acids such as borous acid (e.g., alkyl-B(OH)2 or aryl-B(OH)2), boric acid (i.e., H3BO3), tetraboric acid (i.e., H2B5O7), metaboric acid (i.e., HBO2), ammonium salts of these boron acids, and esters of these boron acids can be used. Using boron trihalides in complexes with ethers, organic acids, inorganic acids, or hydrocarbons is a convenient method for introducing boron reactants into the reaction mixture. Such complexes are known, for example, boron trifluoride-diethyl ether, boron trifluoride-phenol, boron trifluoride-phosphoric acid, boron trichloride-chloroacetic acid, boron tribromide-dioxane, and boron trifluoride-methyl ethyl ether.

[0045] If used, suitable phosphorus compounds for forming the dispersant include phosphorus compounds or mixtures of phosphorus compounds capable of introducing phosphorus-containing substances into the dispersant. Therefore, any organic or inorganic phosphorus compound capable of carrying out this reaction can be used. Thus, inorganic phosphorus compounds such as inorganic phosphoric acid and inorganic phosphorus oxides, including their hydrates, can be used. Typical organophosphorus compounds include full-ester and partial-ester forms of phosphoric acid, such as mono- and di- and tri-esters of phosphate, thiophosphoric acid, dithiophosphoric acid, trithiophosphoric acid, and tetrathiophosphoric acid; mono-, di-, and tri-esters of phosphite, thiophosphite, dithiophosphite, and trithiophosphite; trialkylphosphine oxides; trialkylphosphine sulfides; monoalkylphosphonates and dialkylphosphonates (RPO(OR')(OR”), where R and R' are hydrocarbon groups and R” is a hydrogen atom or a hydrocarbon group), and their monothio, dithio, and trithio analogs; monoalkylphosphonates and dialkylphosphonates (RP(OR')(OR”), where R and R' are hydrocarbon groups and R” is a hydrogen atom or a hydrocarbon group) and their monothio and dithio analogs; and so on. Therefore, compounds such as phosphorous acid (H3PO3, sometimes described as H2(HPO3), sometimes called orthophosphorous acid or phosphonic acid), phosphoric acid (H3PO4, sometimes called orthophosphoric acid), hypophosphoric acid (H4P2O6), metaphosphoric acid (HPO3), pyrophosphoric acid (H4P2O7), hypophosphorous acid (H3PO2, sometimes called hypophosphonic acid), pyrophosphorous acid (H4P2O5, sometimes called pyrophosphonic acid), hypophosphonic acid (H3PO), and tripolyphosphoric acid (H5P3O) can be used. 10 ), tetrapolyphosphoric acid (H5P4O) 13Phosphorus trioxide, phosphorus tetroxide, phosphorus pentoxide, etc. Partial or complete sulfur analogs, such as tetrathioacetic acid (H3PS4), thiophosphoric acid (H3PO3S), dithiophosphoric acid (H3PO2S2), trithiophosphoric acid (H3POS3), sesquisulfide, phosphorus heptasulfide, and phosphorus pentasulfide (P2S5, sometimes called P4S). 10 It can also be used to form the dispersant disclosed herein. Inorganic phosphorus halide compounds, such as PCl3, PBr3, POCl3, PSCl3, etc., can also be used.

[0046] Similarly, organophosphorus compounds such as monoesters, diesters, and trimers of phosphoric acid (e.g., trialkyl phosphates, dialkyl monoacid phosphates, monoalkyl diacid phosphates, and mixtures thereof), monoesters, diesters, and trimers of phosphorous acid (e.g., trialkyl phosphite, dialkyl hydrogen phosphite, alkyl diacid phosphite, and mixtures thereof), phosphonates (“primary” RP(O)(OR)2 and “secondary” R2P(O)(OR)), hypophosphonates, and phosphonyl halides (e.g., RP(O)Cl2 and R2P(O)Cl) can be used. Halogenated phosphites (e.g., (RO)PCl2 and (RO)2PCl), halogenated phosphates (e.g., ROP(O)Cl2 and (RO)2P(O)Cl), tertiary pyrophosphates (e.g., (RO)2P(O)—O—P(O)(OR)2), and all-sulfur or partially-sulfur analogs of any of the aforementioned organophosphorus compounds, wherein each hydrocarbon group contains up to about 100 carbon atoms, preferably up to about 50 carbon atoms, more preferably up to about 24 carbon atoms, and most preferably up to about 12 carbon atoms. Halogenated phosphine halides (e.g., alkyl tetrahalides, dialkyl trihalides, and trialkyl dihalides) and phosphine halides (monohalides and dihalides) may also be used.

[0047] In other methods, the hydrocarbon-substituted succinimide dispersant described herein may have the structure of Formula I:

[0048]

[0049] R1 is a hydrocarbon substituent (or those previously described) with a number-average molecular weight of about 350 to about 5,000; R2, R3, and R4 are independently divalent C1-C6 moieties; R5 and R6 are each independently hydrogen, C1-C6 alkyl groups, or form a 5- or 6-membered ring together with the nitrogen atom to which they are attached, optionally fused with one or more aromatic or non-aromatic rings; n is an integer from 0 to 8; and y and z are each integers, wherein y + z = 1. In some methods, the dispersant is a bis(succinimide), wherein R5 and R6 form a group of formula II together with the nitrogen atom to which they are attached.

[0050]

[0051] In some methods, the acylating agent is maleic anhydride, and the nitrogen source is a polyalkylene polyamine selected from polyethylene polyamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, or a mixture thereof having an average of 5 nitrogen atoms; and the hydrocarbon substituent has a number average molecular weight of about 1,000 to about 2,500.

[0052] The methods and lubricating compositions described herein subsequently include nitrogen-free organic friction modifiers having carboxylic acid and / or hydroxyl side groups that have not been pre-boronized with or pre-reacted with boron-containing compounds. Suitable friction modifiers may comprise metal-free and nitrogen-free organic friction modifiers, and may include, but are not limited to, imidazolines, amides, amines, succinimides, alkoxylated amines, alkoxylated ether amines, amine oxides, amides, nitriles, betaines, quaternary amines, imines, amine salts, aminoguanidines, alkanolamides, phosphonates, glycerides, sulfurized aliphatic compounds and olefins, sunflower oil, other naturally occurring vegetable or animal oils, dicarboxylic acid esters, esters or metaesters of polyols, and one or more aliphatic or aromatic carboxylic acids, etc.

[0053] Suitable friction modifiers may contain a hydrocarbon group selected from straight-chain, branched, or aromatic hydrocarbon groups or mixtures thereof, and may be saturated or unsaturated. The hydrocarbon group may consist of carbon and hydrogen or heteroatoms, such as sulfur or oxygen. The hydrocarbon group may range from about 12 to about 25 carbon atoms. In some embodiments, the friction modifier may be a long-chain fatty acid ester. In another embodiment, the long-chain fatty acid ester may be a monoester, diester, or (tri)glycerol ester. The friction modifier may be a long-chain fatty amide, a long-chain fatty ester, a long-chain fatty epoxide derivative, or a long-chain imidazoline.

[0054] In some methods, friction modifiers may include organic, ashless (metal-free), nitrogen-free organic friction modifiers. Such friction modifiers may comprise esters formed by reacting a carboxylic acid (or fatty acid) and an anhydride with an alkanol, and typically contain a polar end group (e.g., a carboxyl or hydroxyl group) covalently bonded to a lipophilic hydrocarbon chain. Examples of organic ashless nitrogen-free friction modifiers are generally known as glyceryl monooleate (GMO), which may contain blends of monoesters, diesters, and / or triesters of oleic acid. Other suitable friction modifiers are described in U.S. Patent No. 6,723,685, the entire contents of which are incorporated herein by reference. Preferably, the nitrogen-free organic friction modifier has a side hydroxyl group obtained from the reaction of a fatty acid (such as C10 to C20 fatty acids) with an alkanol. In other methods, nitrogen-free organic friction modifiers comprise blends of monoesters and diesters of fatty acids. In other methods, nitrogen-free organic friction modifiers include blends of mono- and diesters of oleic acid, and preferably, nitrogen-free organic friction modifiers primarily include glyceryl monooleate.

[0055] The lubricating compositions described herein may contain up to about 1 wt% of such friction modifier, and in other methods, contain about 0.1 wt% to about 1 wt%, about 0.1 wt% to about 0.8 wt%, about 0.2 wt% to about 0.8 wt%, or any other range therein.

[0056] The lubricating oil composition further includes a blend of a boron-containing compound with the dispersants and friction modifiers discussed above. Preferably, the boron-containing compound is selected from boric acid or one or more borous acids, but suitable boron-containing compounds may include any boron-containing compound or mixture of boron-containing compounds capable of introducing boron-containing substances or reacting with carboxylic acid or hydroxyl groups of nitrogen-free organic friction modifiers. Any organic or inorganic boron compound capable of carrying out such a reaction can be used. Thus, and depending on the friction modifier, boron oxide, boron oxide hydrate, boron trifluoride, boron tribromide, boron trichloride, HBF4 borates such as borous acids (e.g., alkyl-B(OH)2 or aryl-B(OH)2), boric acid (i.e., H3BO3), tetraboric acid (i.e., H2B5O7), metaboric acid (i.e., HBO2), ammonium salts of these borates, and esters of these borates can be used. In some cases, the use of boron trihalides in complexes with ethers, organic acids, inorganic acids, or hydrocarbons is a convenient method for introducing boron reactants into the reaction mixture. Such complexes are known, for example, boron trifluoride-diethyl ether, boron trifluoride-phenol, boron trifluoride-phosphoric acid, boron trichloride-chloroacetic acid, boron tribromide-dioxane, and boron trifluoride-methyl ethyl ether.

[0057] In one method, the boron-containing compound may have the structure XB-(OH)2, wherein X is a hydroxyl group, a straight-chain or branched alkyl group, a cyclic hydrocarbon group, one or more aryl groups, a benzofuranyl group, a dibenzofuranyl group, or a combination thereof. In other methods, the boron-containing compound may be borous acid, wherein X is a straight-chain or branched C1 to C10 group, one or more aryl, benzofuranyl, dibenzofuranyl groups, or a combination thereof. In yet another method, the boron-containing compound may be boric acid, (2-methylpropyl)boronic acid, phenylboronic acid, naphthalene-1-boronic acid, 4-(dibenzofuranyl)boronic acid, or a mixture thereof.

[0058] In the method, the blend of dispersant, friction modifier, and boron-containing compound can be prepared by blending at a temperature of about 50°C to about 100°C (or about 70°C to about 80°C) using a mild blending process of about 100 rpm to 500 rpm. The methods and lubricant compositions described herein contain about 100 ppm to about 300 ppm of boron provided by the boron-containing compound (and excluding boron from any pre-boronized compound), up to about 10 wt% of a hydrocarbon-substituted succinimidyl dispersant (or about 1 wt% to about 8 wt%), and up to about 1 wt% of a nitrogen-free organic friction modifier (or about 0.2 wt% to about 0.8 wt%). While not wishing to be limited by theory, the blends described herein may contain an amount of boron or a amount of a boron-containing compound that can be used for further reaction with the hydroxyl or other acid moieties present in or formed in the composition during use. In other methods, the methods and lubricant compositions described herein may contain about 250 ppm to about 350 ppm of a blend of boron provided by a boron-containing compound and a nitrogen-free organic friction modifier (or other suitable ranges within such endpoints) per 1 wt% of a nitrogen-containing compound.

[0059] In compositions and methods involving such boron and friction modifier weight relationships, and when the friction modifier is not pre-reacted (or pre-boronized) and is merely blended together, the methods and lubricant compositions described herein surprisingly exhibit lead corrosion of no more than about 500 ppm per 1 wt% of nitrogen-free organic friction modifier as measured according to ASTM D6594, compared to no more than about 400 ppm, 300 ppm, 200 ppm, or 150 ppm per wt% of nitrogen-free organic friction modifier in other methods as measured according to ASTM D6594. Even more surprisingly, as shown in the examples below, the lead corrosion of the blends described herein is generally better than that of pre-boronized friction modifiers, and in some cases, even surprisingly better than lubricant compositions without any friction modifiers.

[0060] Lubricating oil composition

[0061] The method described herein involves supplying a lubricating oil composition to an internal combustion engine, the lubricating oil composition comprising, as discussed above, dispersants, friction modifiers, and boron-containing compounds in most base oils or base oil blends. Such blends of the above-described additives may be combined with a major amount of a base oil or base oil blend having a lubricating viscosity (described below) incorporating one or more additional optional additives to produce the lubricating oil composition. In the method, the lubricating oil composition comprises about 50% by weight or more of a base oil blend, about 60% by weight or more, about 70% by weight or more, or about 80% by weight or more to about 95% by weight or less, about 90% by weight or less, about 85% by weight or less of a base oil blend, which is further discussed below.

[0062] Base oil blends The base oil used in the lubricating oil composition described herein may be an oil with lubricating viscosity and selected from any of the Group I to Group V base oils as specified in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. The five groups of base oils are as follows:

[0063] Table 1

[0064]

[0065] Groups I, II, and III are mineral oil processing feedstocks. Group IV base oils contain truly synthetic molecules prepared through the polymerization of olefinic unsaturated hydrocarbons. Many Group V base oils are also truly synthetic products and can include diesters, polyol esters, polyalkylene glycols, alkylated aromatic compounds, polyphosphates, polyethylene ethers, and / or polyphenylene ethers, but can also be naturally occurring oils such as vegetable oils. It should be noted that although Group III base oils are derived from mineral oils, the rigorous processing these fluids undergo results in physical properties very similar to some truly synthetic oils, such as PAO. Therefore, oils derived from Group III base oils can be referred to as synthetic fluids in industry. Group II+ can include high viscosity index Group II oils.

[0066] The base oil blend used in the disclosed lubricating oil composition may be mineral oil, animal oil, vegetable oil, synthetic oil, synthetic oil blends, or mixtures thereof. Suitable oils may be derived from hydrocracked, hydrogenated, hydrorefined, unrefined, refined, and refined oils, as well as mixtures thereof.

[0067] Unrefined oils are those derived from natural, mineral, or synthetic sources with little or no further purification. Refined oils are similar to unrefined oils, except that they undergo one or more purification steps, which may result in improvements in one or more properties. Examples of suitable purification techniques are solvent extraction, double distillation, acid or alkali extraction, filtration, percolation, etc. Oils refined to edible quality may or may not be useful. Edible oils may also be called white oils. In some embodiments, the lubricating oil composition does not contain edible oils or white oils.

[0068] Refined oils, also known as recycled or reprocessed oils, are obtained using the same or similar processes as refined oils. These oils are typically further processed using techniques designed to remove waste additives and oil decomposition products.

[0069] Mineral oils may include oils obtained through drilling or oils derived from plants and animals, or any mixture thereof. For example, such oils may include, but are not limited to, castor oil, lard, olive oil, peanut oil, corn oil, soybean oil, and linseed oil, as well as mineral lubricants, such as liquid petroleum and solvent-treated or acid-treated alkanes, naphthenes, or mixed alkanes-naphthenes. If desired, such oils may be partially or fully hydrogenated. Oils derived from coal or shale may also be applicable.

[0070] Useful synthetic lubricants may include hydrocarbon oils such as polymeric, oligomeric, or copolymeric olefins (e.g., polybutene, polypropylene, propylene-isobutylene copolymers); trimers or oligomers of poly(1-hexene), poly(1-octene), and 1-decene, such as poly(1-decene), which are commonly referred to as α-olefins, and mixtures thereof; alkylbenzenes (e.g., dodecylbenzene, tetradecylbenzene, dinonylbenzene, di-(2-ethylhexyl)benzene); polybenzenes (e.g., biphenyl, terphenyl, alkylated polybenzene); diphenylalkanes, alkylated diphenylalkanes, alkylated diphenyl ethers, and alkylated diphenyl sulfides and their derivatives, analogs, and homologues, or mixtures thereof. Polyα-olefins are typically hydrogenated materials.

[0071] Other synthetic lubricants include phosphoric acid-containing polyol esters, diesters, liquid esters (e.g., diethyl esters of toluene phosphate, trioctyl phosphate, and decanephosphonic acid), or polytetrahydrofurans. Synthetic oils can be produced via the Fischer-Tropsch reaction and are typically hydroisomerized Fischer-Tropsch hydrocarbons or waxes. In one embodiment, the oil can be prepared via a Fischer-Tropsch gas-liquid synthesis process, along with other gas-liquid oils.

[0072] The base oil included in the lubricating composition in a major amount may be selected from Group I, Group II, Group III, Group IV, Group V, and combinations of two or more of the foregoing, and wherein the base oil in a major amount is different from the base oil produced by providing additive components or viscosity index improvers in the composition. In another embodiment, the base oil included in the lubricating composition in a major amount may be selected from Group II, Group III, Group IV, Group V, and combinations of two or more of the foregoing, and wherein the base oil in a major amount is different from the base oil produced by providing additive components or viscosity index improvers in the composition.

[0073] The amount of oil with lubricating viscosity may be the balance remaining after subtracting the total amount of performance additives (including viscosity index improvers and / or pour point depressants and / or other top-treatment additives) from 100% by weight. For example, the amount of oil with lubricating viscosity that may be present in the finished fluid may be the main amount, such as greater than about 50% by weight, greater than about 60% by weight, greater than about 70% by weight, greater than about 80% by weight, greater than about 85% by weight, or greater than about 90% by weight.

[0074] Optional additives :

[0075] The methods and lubricant compositions described herein may, as needed, include a number of optional additives in combination with the dispersants, friction modifiers, and boron-containing compounds discussed above to meet performance criteria, provided that the aforementioned relationships are maintained. Those optional additives are described in the following paragraphs.

[0076] Optional dispersant The lubricating oil composition may optionally include one or more additional dispersants or mixtures thereof. Dispersants are generally referred to as ashless dispersants because they do not contain ash-forming metals before being incorporated into the lubricating oil composition, and typically do not provide any ash when added to the lubricant. Ashless dispersants are characterized by polar groups linked to relatively high molecular weight hydrocarbon chains. Typical ashless dispersants include N-substituted long-chain alkenyl succinimides. Examples of N-substituted long-chain alkenyl succinimides include polyisobutylene succinimides, wherein, as measured by GPC, the number average molecular weight of the polyisobutylene substituent is in the range of about 350 to about 50,000, or about 5,000, or about 3,000. Succinimid dispersants and their preparation are disclosed, for example, in U.S. Patent No. 7,897,696 or U.S. Patent No. 4,234,435. The alkenyl substituent can be prepared from a polymerizable monomer containing about 2 to about 16, or about 2 to about 8, or about 2 to about 6 carbon atoms. Succinimid dispersants are typically polyamines, usually poly(ethylidene) imides.

[0077] Preferred amines are selected from polyamines and hydroxylamines. Examples of polyamines that can be used include, but are not limited to, diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), and higher homologues such as pentaethylaminehexamine (PEHA).

[0078] Suitable heavy polyamines are mixtures of polyalkylene polyamines containing small amounts of lower polyamine oligomers (such as TEPA and PEHA (pentaethylenehexamine)) but primarily having 6 or more nitrogen atoms, 2 or more primary amines, and oligomers with more extensive branching than conventional polyamine mixtures. Heavy polyamines preferably comprise polyamine oligomers containing 7 or more nitrogen atoms per molecule and 2 or more primary amines per molecule. Heavy polyamines contain greater than 28% by weight (e.g., >32% by weight) of total nitrogen and 120-160 g / equivalent of primary amine groups.

[0079] In some methods, the appropriate polyamine is often referred to as PAM and contains a mixture of ethylenediamines, in which TEPA and pentaethylenehexamine (PEHA) are the main components of the polyamine, typically less than about 80%.

[0080] Typically, PAM contains 8.7–8.9 milliequivalents of primary amine per gram (equivalent to 115–112 grams per gram of primary amine) and approximately 33–34% by weight of total nitrogen. Heavy fractions of PAM oligomers, which contain almost no TEPA and only trace amounts of PEHA but primarily oligomers with more than 6 nitrogen atoms and greater branching, can produce dispersants with improved dispersibility.

[0081] In one embodiment, this disclosure further comprises at least one polyisobutylene succinimide dispersant derived from polyisobutylene with a number average molecular weight in the range of about 350 to about 50,000, about 5,000, or about 3,000, as determined by GPC. The polyisobutylene succinimide can be used alone or in combination with other dispersants.

[0082] In some embodiments, polyisobutylene (when included) may have terminal double bonds in amounts greater than 50 mol%, greater than 60 mol%, greater than 70 mol%, greater than 80 mol%, or greater than 90 mol%. This type of PIB is also referred to as highly reactive PIB (“HR-PIB”). HR-PIBs with a number-average molecular weight in the range of about 800 to about 5000, as determined by GPC, are suitable for embodiments of this disclosure. Conventional PIBs typically have terminal double bonds in amounts less than 50 mol%, less than 40 mol%, less than 30 mol%, less than 20 mol%, or less than 10 mol%.

[0083] HR-PIBs with a number-average molecular weight in the range of about 900 to about 3000, as determined by GPC, are suitable. These HR-PIBs are commercially available or can be synthesized by polymerizing isobutylene in the presence of a non-chlorinated catalyst (such as boron trifluoride), as described in U.S. Patent No. 4,152,499 to Boerzel et al. and U.S. Patent No. 5,739,355 to Gateau et al. When used in the aforementioned thermo-olefin reaction, HR-PIBs can increase the conversion rate and reduce the amount of sediment formed due to enhanced reactivity. A suitable method is described in U.S. Patent No. 7,897,696.

[0084] In one embodiment, this disclosure also includes at least one dispersant derived from polyisobutylene succinic anhydride (“PIBSA”). PIBSA may have an average succinic acid fraction between about 1.0 and about 2.0 per polymer.

[0085] Chromatographic techniques can be used to determine the activity percentage of alkenyl or alkyl succinic anhydrides. This method is described in columns 5 and 6 of U.S. Patent No. 5,334,321.

[0086] The conversion percentage of polyolefins is calculated from the activity percentage using the equations in columns 5 and 6 of U.S. Patent No. 5,334,321.

[0087] Unless otherwise stated, all percentages are by weight, and all molecular weights are number average molecular weights determined by gel permeation chromatography (GPC) using commercially available polystyrene standards (with a number average molecular weight of 180 to approximately 18,000 as a calibration reference).

[0088] In one embodiment, the dispersant may be derived from polyalphaolefin (PAO) succinic anhydride. In another embodiment, the dispersant may be derived from an olefin maleic anhydride copolymer. For example, the dispersant may be described as polyPIBSA. In another embodiment, the dispersant may be derived from an anhydride grafted onto an ethylene-propylene copolymer.

[0089] Suitable classes of nitrogen-containing dispersants may be derived from olefin copolymers (OCPs), more specifically, ethylene-propylene dispersants, which may be grafted with maleic anhydride. A more complete list of nitrogen-containing compounds that can react with functionalized OCPs is described in U.S. Patent Nos. 7,485,603; 7,786,057; 7,253,231; 6,107,257; and 5,075,383; and / or are commercially available.

[0090] Another suitable class of dispersants is the Mannich base. Mannich bases are substances formed by the condensation of alkyl-substituted phenols, polyalkylene polyamines, and aldehydes (such as formaldehyde) with higher molecular weight alkyl groups. Mannich bases are described in more detail in U.S. Patent No. 3,634,515.

[0091] Suitable dispersants can also be high molecular weight esters or hemiesteramides. Suitable dispersants can also be post-treated by conventional methods through reaction with any of a variety of reagents. These include boron, urea, thiourea, dimercaptothiadiazole, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, maleic anhydrides, nitriles, epoxides, carbonates, cyclic carbonates, hindered phenolic esters, and phosphorus compounds. US 7,645,726; US 7,214,649; and US 8,048,831 are incorporated herein by reference in their entirety.

[0092] In addition to carbonate and boric acid posttreatments, both compounds can be posttreated or further posttreated using a variety of posttreatment methods designed to improve or impart different properties. Such posttreatments include those outlined in columns 27 through 29 of U.S. Patent No. 5,241,003, which are incorporated herein by reference. Such treatments include treatments with: inorganic phosphorous acid or anhydrous substances (e.g., U.S. Patent Nos. 3,403,102 and 4,648,980); organophosphorus compounds (e.g., U.S. Patent No. 3,502,677); phosphorus pentasulfide; boron compounds as mentioned above (e.g., U.S. Patent Nos. 3,178,663 and 4,652,387); carboxylic acids, polycarboxylic acids, acid anhydrides, and / or acidic halides (e.g., U.S. Patent Nos. 3,708,522 and 4,948). 386); epoxides, polyepoxides, or thioepoxides (e.g., U.S. Patents 3,859,318 and 5,026,495); aldehydes or ketones (e.g., U.S. Patent No. 3,458,530); carbon disulfide (e.g., U.S. Patent No. 3,256,185); glycidyl (e.g., U.S. Patent No. 4,617,137); urea, thiourea, or guanidine (e.g., U.S. Patent Nos. 3,312,619; 3,865,813; and British Patent GB 1,065,595); organic sulfonic acids (e.g., U.S. Patent No. 3,189,544 and British Patent GB 1,065,595). 2,140,811); alkenyl cyanides (e.g., U.S. Patent Nos. 3,278,550 and 3,366,569); dienoketones (e.g., U.S. Patent No. 3,546,243); diisocyanates (e.g., U.S. Patent No. 3,573,205); alkane sulcolepsy (e.g., U.S. Patent No. 3,749,695); 1,3-dicarbonyl compounds (e.g., U.S. Patent No. 4,579,675); sulfates of alkoxylated alcohols or phenols (e.g., U.S. Patent No. 3,954,6... 39); cyclic lactones (e.g., U.S. Patent Nos. 4,617,138; 4,645,515; 4,668,246; 4,963,275; and 4,971,711); cyclic carbonates or thiocarbonates; linear monocarbonates or polycarbonates, or chloroformates (e.g., U.S. Patent Nos. 4,612,132; 4,647,390; 4,648,886; 4,670,170); nitrogen-containing carboxylic acids (e.g., U.S. Patent No. 4,971,598 and British Patent GB). 2,140,811); hydroxyl-protected chlorodicarbonyloxy compounds (e.g., U.S. Patent No. 4,614,522); lactams, thiolactams, thiolactones, or dithiolactones (e.g., U.S. Patent Nos. 4,614,603 and 4,666,460); cyclic carbonates or thiocarbonates; linear monocarbonates or polycarbonates, or chloroformates (e.g., U.S. Patent Nos. 4,612,132; 4,647,390; 4,646,860; and 4,670,170);Nitrogenous carboxylic acids (e.g., U.S. Patent No. 4,971,598 and British Patent GB 2,440,811); hydroxyl-protected chlorodicarbonyloxy compounds (e.g., U.S. Patent No. 4,614,522); lactams, thiolactams, thiolactones, or dithiolactones (e.g., U.S. Patent Nos. 4,614,603 and 4,666,460); cyclic carbamates, cyclic thiocarbamates, or cyclic dithiocarbamates (e.g., U.S. Patent Nos. 4,663,062 and 4,666,459); hydroxy aliphatic carboxylic acids (e.g., U.S. Patent Nos. 4,482,464; 4,520). 1,318; 4,713,189); oxidizing agents (e.g., U.S. Patent No. 4,379,064); combinations of phosphorus pentasulfide and polyalkylene polyamines (e.g., U.S. Patent No. 3,185,647); combinations of carboxylic acids or aldehydes or ketones and sulfur or sulfur chloride (e.g., U.S. Patent Nos. 3,390,086; 3,470,098); combinations of hydrazine and carbon disulfide (e.g., U.S. Patent No. 3,519,564); combinations of aldehydes and phenols (e.g., U.S. Patent Nos. 3,649,229; 5,030,249; 5,039,307); combinations of aldehydes and O-diesters of dithiophosphate. (e.g., U.S. Patent No. 3,865,740); combinations of hydroxyaliphatic carboxylic acids and boric acid (e.g., U.S. Patent No. 4,554,086); combinations of hydroxyaliphatic carboxylic acids, then formaldehyde and phenol (e.g., U.S. Patent No. 4,636,322); combinations of hydroxyaliphatic carboxylic acids and then aliphatic dicarboxylic acids (e.g., U.S. Patent No. 4,663,064); combinations of formaldehyde and phenol and then glycolic acid (e.g., U.S. Patent No. 4,699,724); combinations of hydroxyaliphatic carboxylic acids or oxalic acid, and then diisocyanates (e.g., U.S. Patent No. 4,713,191); inorganic acids of phosphorus or Combinations of acid anhydrides or their sulfur analogs with boron-containing compounds (e.g., U.S. Patent No. 4,857,214); combinations of organic diacids, then unsaturated fatty acids, then nitrosoaromatic amines, optionally followed by boron compounds, and then ethanol acidifying agents (e.g., U.S. Patent No. 4,973,412); combinations of aldehydes and triazoles (e.g., U.S. Patent No. 4,963,278); combinations of aldehydes and triazoles, then boron compounds (e.g., U.S. Patent No. 4,981,492); combinations of cyclic lactones and boron compounds (e.g., U.S. Patent Nos. 4,963,275 and 4,971,711). The patents mentioned above are incorporated herein by reference in their entirety.

[0093] The TBN of a suitable dispersant on an oil-free basis can be from about 10 mg to about 65 mg KOH / g, and if measured on a dispersant sample containing about 50% diluent oil, it is equivalent to about 5 TBN to about 30 TBN. TBN is measured according to the method of ASTM D2896.

[0094] In another embodiment, the optional dispersant additive may be a hydrocarbon-substituted succinamide or succinimide dispersant. In the method, the hydrocarbon-substituted succinamide or succinimide dispersant is derived from a hydrocarbon-substituted acylation agent reacted with a polyalkylene polyamine, and wherein, as measured by GPC using polystyrene as a calibration reference, the hydrocarbon substituent of the succinamide or succinimide dispersant is a straight-chain or branched hydrocarbon group with a number average molecular weight of about 250 to about 5,000.

[0095] In some methods, the polyalkylene polyamine used to form the dispersant has the formula...

[0096]

[0097] Each R and R' is independently a divalent C1 to C6 alkylene linking group, each R1 and R2 is independently a hydrogen, a C1 to C6 alkyl group, or a 5- or 6-membered ring optionally fused with one or more aromatic or non-aromatic rings together with the nitrogen atom to which they are attached, and n is an integer between 0 and 8. In other methods, the polyalkylene polyamine is selected from the group consisting of: mixtures of polyethylene polyamines having an average of 5 to 7 nitrogen atoms, triethylenetetramine, tetraethylenepentamine, and combinations thereof.

[0098] If an optional dispersant is present, it may be sufficient to provide up to about 20% by weight for use based on the final weight of the lubricating oil composition. Another amount of dispersant that may be used based on the final weight of the lubricating oil composition may be about 0.1% to about 15% by weight, or about 0.1% to about 10% by weight, or about 0.1% to about 8% by weight, or about 1% to about 10% by weight, or about 1% to about 8% by weight, or about 1% to about 6% by weight. In some embodiments, the lubricating oil composition utilizes a mixed dispersant system. A single type of dispersant or a mixture of two or more types of dispersants may be used in any desired ratio.

[0099] antioxidants The lubricating oil compositions described herein may optionally contain one or more antioxidants. Antioxidant compounds are known and include, for example, phenolates, phenolate sulfides, sulfide olefins, phosphosulfur terpenes, sulfide esters, aromatic amines, alkylated diphenylamines (e.g., nonyldiphenylamine, dinonyldiphenylamine, octyldiphenylamine, dioctyldiphenylamine), phenyl-α-naphthylamine, alkylated phenyl-α-naphthylamine, hindered nonaromatic amines, phenols, hindered phenols, oil-soluble molybdenum compounds, macromolecular antioxidants, or mixtures thereof. Antioxidant compounds may be used alone or in combination.

[0100] Hindered phenolic antioxidants may contain sec-butyl and / or tert-butyl groups as sterically hindered groups. The phenolic group may be further substituted with a hydrocarbon group and / or a bridging group attached to a second aromatic group. Examples of suitable hindered phenolic antioxidants include 2,6-di-tert-butylphenol, 4-methyl-2,6-di-tert-butylphenol, 4-ethyl-2,6-di-tert-butylphenol, 4-propyl-2,6-di-tert-butylphenol, or 4-butyl-2,6-di-tert-butylphenol, or 4-dodecyl-2,6-di-tert-butylphenol. In one embodiment, the hindered phenolic antioxidant may be an ester and may include, for example, Irganox, available from BASF. TM L-135 may be derived from the addition product of 2,6-di-tert-butylphenol and alkyl acrylate, wherein the alkyl group may contain about 1 to about 18, or about 2 to about 12, or about 2 to about 8, or about 2 to about 6, or about 4 carbon atoms. Another commercially available hindered phenolic antioxidant may be an ester and may include Ethanox, available from Albemarle Corporation. TM 4716.

[0101] Available antioxidants may include diarylamines and high molecular weight phenols. In one embodiment, the lubricating oil composition may contain a mixture of diarylamines and high molecular weight phenols, such that each antioxidant may be sufficient to provide up to about 5% by weight based on the final weight of the lubricating oil composition. In another embodiment, based on the final weight of the lubricating oil composition, the antioxidant may be a mixture of about 0.3 to about 1.5% by weight of diarylamine and about 0.4 to about 2.5% by weight of high molecular weight phenols.

[0102] Examples of suitable olefins that can be vulcanized to form vulcanized olefins include propylene, butene, isobutene, polyisobutene, pentene, hexene, hepten, octene, nonene, decene, undecene, dodecene, tridecene, tetradecene, pentadecene, hexadecene, heptadecene, octadecadecene, nonadecene, eicosene, or mixtures thereof. In one embodiment, hexadecene, heptadecene, octadecadecene, nonadecene, eicosene, or mixtures thereof, as well as their dimers, trimers, and tetramers, are particularly suitable olefins. Alternatively, the olefin may be a Diels-Alder adduct of a diene (such as 1,3-butadiene) and an unsaturated ester (such as butyl acrylate).

[0103] Another class of sulfurized olefins includes sulfurized fatty acids and their esters. Fatty acids are typically derived from vegetable or animal oils and generally contain about 4 to about 22 carbon atoms. Examples of suitable fatty acids and their esters include triglycerides, oleic acid, linoleic acid, palmitic acid, or mixtures thereof. Typically, fatty acids are derived from lard, pine oil, peanut oil, soybean oil, cottonseed oil, sunflower oil, or mixtures thereof. Fatty acids and / or esters can be mixed with olefins such as α-olefins.

[0104] In another alternative embodiment, in addition to the phenolic and / or amine antioxidants discussed above, the antioxidant composition also contains a molybdenum-containing antioxidant. When using a combination of these three antioxidants, preferably, the ratio of the phenolic antioxidant to the amine antioxidant to the molybdenum-containing antioxidant is (0 to 2):(0 to 2):(0 to 1).

[0105] The one or more antioxidants may be present in the range of about 0% by weight to about 20% by weight, or about 0.1% by weight to about 10% by weight, or about 1% by weight to about 5% by weight of the lubricating oil composition.

[0106] Anti-wear agent The lubricating oil compositions described herein may optionally contain one or more anti-wear agents. Examples of suitable additional anti-wear agents include, but are not limited to, metal thiophosphates; metal dialkyl dithiophosphates; phosphate esters or salts thereof; phosphate esters; phosphites; phosphoric acid esters, ethers or amides; sulfurized olefins; compounds containing thiocarbamates, including thiocarbamates, alkylene-coupled thiocarbamates and bis(S-alkyldithiocarbamoyl) disulfides; and mixtures thereof. A suitable anti-wear agent may be molybdenum dithiocarbamate. Phosphorus-containing anti-wear agents are described more fully in European Patent 612 839. The metal in the dialkyl dithiophosphate may be an alkali metal, an alkaline earth metal, aluminum, lead, tin, molybdenum, manganese, nickel, copper, titanium or zinc. A suitable anti-wear agent may be zinc dialkyl dithiophosphate.

[0107] Another example of a suitable anti-wear agent includes titanium compounds, tartrate esters, tartrate imides, oil-soluble amine salts of phosphorus compounds, sulfurized olefins, phosphites (such as dibutyl phosphite), phosphonates, and compounds containing thiocarbamates (such as thiocarbamates, thiocarbamate amides, thiocarbamate ethers, alkylene-coupled thiocarbamates, and bis(S-alkyldithiocarbamoyl) disulfides). The tartrate ester or tartrate imide may contain an alkyl ester group, wherein the total number of carbon atoms in the alkyl group may be at least 8. In one embodiment, the anti-wear agent may include a citrate ester.

[0108] The anti-wear agent may be present in the range of about 0% to about 15% by weight, or about 0.01% to about 10% by weight, or about 0.05% to about 5% by weight, or about 0.1% to about 3% by weight of the lubricating oil composition.

[0109] Cleaning agentsThe lubricating oil composition may optionally contain one or more neutral, low-alkaline, or high-alkaline detergents, or mixtures thereof. Suitable additional detergent matrices include benzoates, sulfur-containing benzoates, sulfonates, calixates, salicylates, salicylates, carboxylic acids, phosphoric acid, monothiophosphoric acid and / or dithiophosphoric acid, alkylphenols, thiocoupled alkylphenol compounds, or methylene-bridged phenols. Suitable detergents and methods of their preparation are described in more detail in several patent publications, including US 7,732,390 and the references cited therein.

[0110] The detergent matrix can be salted with, for example, but not limited to, the following alkali metals or alkaline earth metals: calcium, magnesium, potassium, sodium, lithium, barium, or mixtures thereof. In some embodiments, the detergent is barium-free. In some embodiments, the detergent may contain trace amounts of other metals, such as magnesium or calcium, such as 50 ppm or less, 40 ppm or less, 30 ppm or less, 20 ppm or less, or 10 ppm or less. Suitable detergents may include alkali metal or alkaline earth metal salts of petroleum sulfonic acids and long-chain mono- or dialkyl aryl sulfonic acids, wherein the aryl group is benzyl, tolyl, or xylyl. Examples of suitable detergents include, but are not limited to: calcium phenolate, calcium sulfonate, calcium calixarates, calcium salixarates, calcium salicylate, calcium carboxylate, calcium phosphate, calcium monothiophosphate and / or calcium dithiophosphate, calcium alkylphenolate, calcium thiocoupled alkylphenolate compounds, methylene-bridged calcium phenolate, magnesium phenolate, magnesium sulfonate, magnesium calixarates, magnesium salixarates, magnesium salicylate, magnesium carboxylate, magnesium phosphate, magnesium monothiophosphate and / or magnesium dithiophosphate, magnesium alkylphenolate, magnesium thiocoupled alkylphenolate compounds, methylene-bridged magnesium phenolate, sodium phenolate, sodium sulfonate, sodium calixarate. calixarates), sodium salixarates, sodium salicylate, sodium carboxylate, sodium phosphate, sodium monothiophosphate and / or sodium dithiophosphate, sodium alkylphenolate, sodium thiocoupled alkylphenolate compound, or sodium methylene-bridged phenolate.

[0111] Highly alkaline detergent additives are well known in the art and can be alkali metal or alkaline earth metal highly alkaline detergent additives. These detergent additives are prepared by reacting a metal oxide or metal hydroxide with a matrix and carbon dioxide gas. The matrix is ​​typically an acid, such as aliphatic-substituted sulfonic acids, aliphatic-substituted carboxylic acids, or aliphatic-substituted phenols.

[0112] The total base number (TBN) of the highly alkaline detergent in the lubricating oil composition may be about 200 mg KOH / g or greater, or, as in other examples, about 250 mg KOH / g or greater, or about 350 mg KOH / g or greater, or about 375 mg KOH / g or greater, or about 400 mg KOH / g or greater.

[0113] Examples of suitable high-alkalinity detergents include, but are not limited to: high-alkalinity calcium phenolate, high-alkalinity calcium sulfur-containing phenolate, high-alkalinity calcium sulfonate, high-alkalinity calcium calixarate, high-alkalinity calcium salicylate, high-alkalinity calcium carboxylate, high-alkalinity calcium phosphate, high-alkalinity calcium monothiophosphate and / or calcium dithiophosphate, high-alkalinity calcium alkylphenolate, high-alkalinity calcium sulfur-coupled alkylphenolate, high-alkalinity calcium methylene-bridged phenolate, high-alkalinity magnesium phenolate, high-alkalinity magnesium sulfur-containing phenolate, high-alkalinity magnesium sulfonate, high-alkalinity magnesium calixarate, high-alkalinity magnesium salicylate, high-alkalinity magnesium carboxylate, high-alkalinity magnesium phosphate, high-alkalinity magnesium monothiophosphate and / or magnesium dithiophosphate, high-alkalinity magnesium alkylphenolate, high-alkalinity magnesium sulfur-coupled alkylphenolate, or high-alkalinity magnesium methylene-bridged phenolate.

[0114] The total base value of high-alkalinity calcium phenolate detergents is at least about 150 mg KOH / g, at least about 225 mg KOH / g, at least about 225 mg KOH / g to about 400 mg KOH / g, at least about 225 mg KOH / g to about 350 mg KOH / g, or about 230 mg KOH / g to about 350 mg KOH / g, all as measured by the method of ASTM D-2896. When such detergent compositions are formed in an inert diluent (e.g., process oil, typically mineral oil), the total base value reflects the alkalinity of the overall composition, which includes the diluent and any other materials that may be contained in the detergent composition (e.g., accelerators, etc.).

[0115] The metal-to-matrix ratio of the highly alkaline detergent can be 1.1:1, 2:1, 4:1, 5:1, 7:1, or 10:1. In some embodiments, the detergent is effective in reducing or preventing rust in engine or other automotive components such as transmissions or gears. The detergent may be present in the lubricating oil composition from about 0% to about 10% by weight, or from about 0.1% to about 8% by weight, or from about 1% to about 4% by weight, or greater than about 4% to about 8% by weight.

[0116] Extreme pressure agentThe lubricating oil compositions described herein may optionally contain one or more extreme pressure agents. Oil-soluble extreme pressure (EP) agents include sulfur-containing and chlorine-containing sulfur EP agents, chlorinated hydrocarbon EP agents, and phosphorus EP agents. Examples of such EP agents include chlorinated waxes; organosulfurs and polysulfides, such as dibenzyl disulfide, bis(chlorobenzyl) disulfide, dibutyltetrasulfide, methyl oleate sulfur, alkyl phenol sulfur, dipentene sulfur, terpenes sulfur, Diels-Alder sulfur; phosphorus sulfides, such as the reaction products of phosphorus sulfide with turpentine or methyl oleate; phosphites, such as dialkyl phosphites and trialkyl phosphites, for example, dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, pentylphenyl phosphite; dipentylphenyl phosphite, tridecyl phosphite, distearate phosphite, and polypropylene-substituted phenyl phosphites; metal thiocarbamates, such as zinc dioctyl dithiocarbamate and barium heptylphenol diacid; amine salts of alkyl and dialkyl phosphates, including, for example, amine salts of the reaction products of dialkyl dithiophosphite with propylene oxide; and mixtures thereof.

[0117] Other friction modifiers The lubricating oil compositions described herein may optionally contain one or more additional friction modifiers. Suitable friction modifiers may include metal-containing and metal-free friction modifiers, and may include, but are not limited to, imidazolines, amides, amines, succinimides, alkoxylated amines, alkoxylated ether amines, amine oxides, amides, nitriles, betaine, quaternary amines, imines, amine salts, aminoguanidines, alkanolamides, phosphonates, metal-containing compounds, glycerides, sulfurized aliphatic compounds and olefins, sunflower oil, other naturally occurring vegetable or animal oils, dicarboxylic acid esters, esters or metaesters of polyols, and one or more aliphatic or aromatic carboxylic acids.

[0118] Suitable friction modifiers may contain a hydrocarbon group selected from straight-chain, branched, or aromatic hydrocarbon groups or mixtures thereof, and may be saturated or unsaturated. The hydrocarbon group may consist of carbon and hydrogen or heteroatoms, such as sulfur or oxygen. The hydrocarbon group may range from about 12 to about 25 carbon atoms. In some embodiments, the friction modifier may be a long-chain fatty acid ester. In another embodiment, the long-chain fatty acid ester may be a monoester, diester, or (tri)glycerol ester. The friction modifier may be a long-chain fatty amide, a long-chain fatty ester, a long-chain fatty epoxide derivative, or a long-chain imidazoline.

[0119] Other suitable friction modifiers may include organic, ashless (metal-free), nitrogen-free organic friction modifiers. Such friction modifiers may comprise esters formed by reacting carboxylic acids and anhydrides with alkanols, and generally contain polar end groups (e.g., carboxyl or hydroxyl groups) covalently bonded to a lipophilic hydrocarbon chain. Examples of organic ashless and nitrogen-free friction modifiers are generally known as glyceryl monooleate (GMO), which may contain monoesters, diesters, and trimers of oleic acid. Other suitable friction modifiers are described in U.S. Patent No. 6,723,685, the entire contents of which are incorporated herein by reference.

[0120] Amine friction modifiers may include amines or polyamines. These compounds may have straight-chain, saturated or unsaturated hydrocarbon groups, or mixtures thereof, and may contain about 12 to about 25 carbon atoms. Other examples of suitable friction modifiers include alkoxylated amines and alkoxylated ether amines. These compounds may have straight-chain, saturated or unsaturated hydrocarbon groups, or mixtures thereof. They may contain about 12 to about 25 carbon atoms. Examples include ethoxylated amines and ethoxylated ether amines.

[0121] Amines and amides may be used as is or as additions or reaction products with boron compounds such as boron oxide, boron halide, metaborates, boric acid or monoalkyl, dialkyl or trialkyl esters of borate. Other suitable friction modifiers are described in U.S. Patent No. 6,300,291, the entire contents of which are incorporated herein by reference.

[0122] Additional friction modifiers may optionally be present in the range of, for example, from about 0% to about 10% by weight, or from about 0.01% to about 8% by weight, or from about 0.1% to about 4% by weight.

[0123] molybdenum-containing components The lubricating oil compositions described herein may optionally contain one or more molybdenum-containing compounds. Oil-soluble molybdenum compounds may have functional properties as anti-wear agents, antioxidants, friction modifiers, or mixtures thereof. Oil-soluble molybdenum compounds may include molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, molybdenum dithiophosphonite, amine salts of molybdenum compounds, molybdenum xanthate, molybdenum thioxanthate, molybdenum sulfide, molybdenum carboxylate, molybdenum alkanolate, trinuclear organomolybdenum compounds, and / or mixtures thereof. Molybdenum sulfide includes molybdenum dithiophosphate. Molybdenum dithiophosphate may be in the form of a stable dispersion. In one embodiment, the oil-soluble molybdenum compound may be selected from molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, amine salts of molybdenum compounds, and mixtures thereof. In one embodiment, the oil-soluble molybdenum compound may be molybdenum dithiocarbamate.

[0124] Suitable examples of usable molybdenum compounds include commercial substances sold under trademarks such as Molyvan 822 from RTVanderbilt Co., Ltd.TM Molyvan TM A, Molyvan2000 TM And Molyvan 855 TM And Sakura-Lube, available from Adeka Corporation. TM S-165, S-200, S-300, S-310G, S-525, S-600, S-700, and S-710, and mixtures thereof. Suitable molybdenum compositions are described in US 5,650,381; US ​​RE 37,363E1; US ​​RE 38,929E1; and US RE 40,595E1, the entire contents of which are incorporated herein by reference.

[0125] Additionally, the molybdenum compound can be an acidic molybdenum compound. This includes molybdic acid, ammonium molybdate, sodium molybdate, potassium molybdate, and other alkali metal salts of molybdate, as well as other molybdenum salts such as sodium hydrogen molybdate, MoOCl4, MoO2Br2, Mo2O3Cl6, molybdenum trioxide, or similar acidic molybdenum compounds. Alternatively, these compositions may provide molybdenum via molybdenum / sulfur complexes of basic nitrogen compounds, as described, for example, in U.S. Patent Nos. 4,263,152; 4,285,822; 4,283,295; 4,272,387; 4,265,773; 4,261,843; 4,259,195 and 4,259,194; and WO 94 / 06897, the entire contents of which are incorporated herein by reference.

[0126] Another suitable class of organomolybdenum compounds are trinuclear molybdenum compounds, such as those having the formula Mo3SkLnQz and mixtures thereof, where S represents sulfur, L represents an independently selected ligand with an organic group having a number of carbon atoms sufficient to impart solubility or dispersibility of the compound in oil, n is 1 to 4, k varies from 4 to 7, Q is selected from the group of neutral electron-donating compounds, such as water, amines, alcohols, phosphine, and ethers, and z is in the range of 0 to 5 and includes non-stoichiometric values. A total of at least 21 carbon atoms, such as at least 25, at least 30, or at least 35 carbon atoms, may be present in the organic group of all ligands. Further suitable molybdenum compounds are described in U.S. Patent No. 6,723,685, the entire contents of which are incorporated herein by reference.

[0127] Oil-soluble molybdenum compounds may be present in amounts sufficient to provide molybdenum of about 0.5 ppm to about 2000 ppm, about 1 ppm to about 700 ppm, about 1 ppm to about 550 ppm, about 5 ppm to about 300 ppm, or about 20 ppm to about 250 ppm.

[0128] compounds containing transition metalsIn another embodiment, the oil-soluble compound may be a compound or metalloid containing a transition metal. Transition metals may include, but are not limited to, titanium, vanadium, copper, zinc, zirconium, molybdenum, tantalum, and tungsten. Suitable metalloids include, but are not limited to, boron, silicon, antimony, and tellurium.

[0129] In one embodiment, the oil-soluble transition metal-containing compound may function as an anti-wear agent, friction modifier, antioxidant, deposit control additive, or more than one of these functions. In one embodiment, the oil-soluble transition metal-containing compound may be an oil-soluble titanium compound, such as titanium(IV) alkoxide. Various Ti(IV) compounds, such as titanium oxide (IV); titanium sulfide (IV); titanium nitrate (IV); titanium(IV) alkoxides, such as titanium methoxide, titanium ethanol, titanium propoxide, titanium isopropoxide, titanium butoxide, titanium 2-ethylhexanol; and other titanium compounds or complexes, including but not limited to titanium phenolate; titanium carboxylate, such as titanium 2-ethyl-1-3-adipic acid (IV) or titanium citrate or titanium oleate; and titanium (triethanolamine) isopropoxide (IV). Other forms of titanium covered within the disclosed technology include titanium phosphate, such as titanium dithiophosphate (e.g., dialkyl titanium dithiophosphate), and titanium sulfonate (e.g., titanium alkylbenzene sulfonate), or generally, reaction products of titanium compounds reacting with various acidic materials to form salts (e.g., oil-soluble salts). Titanium compounds can therefore be derived, in particular, from organic acids, alcohols, and glycols. Ti compounds can also exist in dimer or oligomeric forms, containing a Ti-O-Ti structure. These titanium materials are commercially available or can be readily prepared using suitable synthetic techniques readily apparent to those skilled in the art. They exist in solid or liquid form at room temperature, depending on the specific compound. They can also be provided as solutions in suitable inert solvents.

[0130] In one embodiment, titanium can be supplied as a Ti-modified dispersant, such as a succinimide dispersant. Such materials can be prepared by forming a titanium mixed anhydride between a titanium alkoxide and a hydrocarbon-substituted succinic anhydride (such as an alkenyl (or alkyl) succinic anhydride). The resulting titanate-succinate intermediate can be used directly, or it can react with any of a number of materials, such as (a) polyamine-based succinimide / amide dispersants having free, condensable --NH functional groups; (b) components of polyamine-based succinimide / amide dispersants, namely alkenyl-(or alkyl-)succinic anhydrides and polyamines; and (c) hydroxyl-containing polyester dispersants prepared by reacting substituted succinic anhydrides with polyols, amino alcohols, polyamines, or mixtures thereof. Alternatively, the titanate-succinate intermediate can be reacted with other reagents, such as alcohols, amino alcohols, ether alcohols, polyether alcohols, or polyols or fatty acids, and the product can be used directly to impart Ti to lubricants, or additionally, as described herein, with a succinic acid dispersant. As an example, 1 part (molar) of tetraisopropyl titanate can be reacted with about 2 parts (molar) of polyisobutylene-substituted succinic anhydride at 140-150°C for 5 to 6 hours to provide a titanium-modified dispersant or intermediate. The resulting material (30 g) can be further reacted with a mixture of a succinimide dispersant derived from polyisobutylene-substituted succinic anhydride and a polyethylidene polyamine mixture (127 g + diluent oil) at 150°C for 1.5 hours to produce a titanium-modified succinimide dispersant.

[0131] Another titanium-containing compound can be a titanium alkoxide with C6 to C6 atoms. 25 The reaction products of carboxylic acids. The reaction products can be represented by the following formula:

[0132]

[0133] Where n is an integer selected from 2, 3, and 4, and R is a hydrocarbon group containing approximately 5 to approximately 24 carbon atoms, or is represented by the following formula:

[0134]

[0135] Where m+n=4 and n is in the range of 1 to 3, R4 is an alkyl moiety with 1 to 8 carbon atoms, R1 is selected from hydrocarbon groups containing about 6 to 25 carbon atoms, and R2 and R3 are the same or different and are selected from hydrocarbon groups containing about 1 to 6 carbon atoms, or titanium compounds can be represented by the following formula:

[0136]

[0137] Where x is in the range of 0 to 3, R1 is selected from hydrocarbon groups containing about 6 to 25 carbon atoms, R2 and R3 are the same or different and are selected from hydrocarbon groups containing about 1 to 6 carbon atoms, and R4 is selected from H, or C6 to C4. 25 A group consisting of carboxylic acid moieties.

[0138] Suitable carboxylic acids may include, but are not limited to, hexanoic acid, octanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, oleic acid, erucic acid, linoleic acid, linolenic acid, cyclohexanecarboxylic acid, phenylacetic acid, benzoic acid, neodecanoic acid, etc.

[0139] In embodiments, the oil-soluble titanium compound may be present in the lubricating oil composition in amounts of 0 to 3000 ppm titanium by weight, or 25 to 1500 ppm titanium by weight, or about 35 to 500 ppm titanium by weight, or about 50 ppm to 300 ppm titanium by weight.

[0140] Viscosity index improver The lubricating oil compositions described herein may optionally contain one or more viscosity index improvers. Suitable viscosity index improvers may comprise polyolefins, olefin copolymers, ethylene / propylene copolymers, polyisobutylene, hydrogenated styrene-isoprene polymers, styrene / maleate copolymers, hydrogenated styrene / butadiene copolymers, hydrogenated isoprene polymers, α-olefin maleic anhydride copolymers, polymethyl methacrylates, polyacrylates, polyalkylstyrene, hydrogenated alkenyl aryl conjugated diene copolymers, or mixtures thereof. Viscosity index improvers may include star polymers, and suitable examples are described in U.S. Publication No. 20120101017A1.

[0141] In addition to or in place of viscosity index improvers, the lubricating oil compositions described herein may optionally contain one or more dispersant viscosity index improvers. Suitable viscosity index improvers may include functionalized polyolefins, such as ethylene-propylene copolymers functionalized with the reaction product of an acylation agent (such as maleic anhydride) and an amine; amine-functionalized polymethacrylates; or esterified maleic anhydride-styrene copolymers reacted with an amine.

[0142] The total amount of viscosity index improver and / or dispersant may be from about 0% to about 20% by weight, from about 0.1% to about 15% by weight, from about 0.1% to about 12% by weight, or from about 0.5% to about 10% by weight of the lubricating oil composition.

[0143] Other optional additivesOther additives may be selected to perform one or more functions required for lubrication. Additionally, one or more of the mentioned additives may be multifunctional and provide functions other than those specified herein. Any lubricating oil composition according to this disclosure may optionally contain other performance additives. Other performance additives may be additives other than those specified in this disclosure and / or may include one or more of the following: metal passivators, viscosity index improvers, detergents, ashless TBN accelerators, friction modifiers, anti-wear agents, corrosion inhibitors, rust inhibitors, dispersants, dispersant viscosity index improvers, extreme pressure agents, antioxidants, foam inhibitors, demulsifiers, emulsifiers, pour point depressants, sealing swelling agents, and mixtures thereof. Typically, a fully formulated lubricating oil will contain one or more of these performance additives.

[0144] Suitable metal passivating agents may include derivatives of benzotriazole (typically toluenetriazole), dimercaptothiadiazole derivatives, 1,2,4-triazole, benzimidazole, 2-alkyldithiobenzimidazole, or 2-alkyldithiobenzothiazole; foam inhibitors, including copolymers of ethyl acrylate and 2-ethylhexyl acrylate and optionally vinyl acetate; demulsifiers, including trialkyl phosphate, polyethylene glycol, polyethylene oxide, polypropylene oxide, and (ethylene oxide-propylene oxide) polymers; and pour point depressants, including maleic anhydride-styrene esters, polymethacrylates, polyacrylates, or polyacrylamide.

[0145] Suitable foam inhibitors include silicon-based compounds, such as siloxanes.

[0146] Suitable pour point depressants may include polymethyl methacrylate or mixtures thereof. The pour point depressant may be present in an amount sufficient to provide from about 0% to about 1% by weight, from about 0.01% to about 0.5% by weight, or from about 0.02% to about 0.04% by weight based on the final weight of the lubricating oil composition.

[0147] Suitable rust inhibitors can be single compounds or mixtures of compounds that have the property of inhibiting corrosion on ferrous metal surfaces. Non-limiting examples of useful rust inhibitors herein include: oil-soluble high molecular weight organic acids, such as 2-ethylhexanoic acid, lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, behenic acid, and waxic acid; and oil-soluble polycarboxylic acids, including dimer and trimer acids, such as those derived from pine fatty acids, oleic acid, and linoleic acid. Other suitable corrosion inhibitors include long-chain α,ω-dicarboxylic acids with molecular weights ranging from about 600 to about 3000, and alkenyl succinic acids in which the alkenyl group contains about 10 or more carbon atoms, such as tetrapropylene succinic acid, tetradecenyl succinic acid, and hexadecenyl succinic acid. Another type of acidic corrosion inhibitor available is a half-ester of alkenyl succinic acid having about 8 to about 24 carbon atoms in the alkenyl group with an alcohol (such as polyethylene glycol). Corresponding semiamides of such alkenyl succinic acids are also useful. Useful rust inhibitors are high molecular weight organic acids. If a rust inhibitor is present, it may be used in amounts sufficient to provide about 0% to about 5% by weight, about 0.01% to about 3% by weight, or about 0.1% to about 2% by weight, based on the final weight of the lubricating oil composition.

[0148] Generally, the methods and lubricant compositions described herein may include additive components within the range listed in the table below.

[0149] Table 2: Suitable Lubricating Compositions

[0150]

[0151] Based on the weight of the final lubricating oil composition, the percentages for each component above represent the weight percentage of each component. The remainder of the lubricating oil composition consists of one or more base oils. Additives used to formulate the compositions described herein may be blended into the base oils individually or in various sub-combinations. However, it may be suitable to simultaneously blend all components using an additive concentrate (i.e., additive plus a diluent, such as a hydrocarbon solvent). Fully formulated lubricants typically contain an additive package, referred to herein as a dispersant / inhibitor package or DI package, which will supply the desired characteristics in the formulation.

[0152] Example

[0153] The following examples illustrate exemplary embodiments of this disclosure. In these examples, and elsewhere in this application, all ratios, parts, and percentages are by weight unless otherwise stated. These examples are intended to be presented for illustrative purposes only and are not intended to limit the scope of the invention disclosed herein.

[0154] Comparative Example 1

[0155] The lead corrosion of lubricants containing increased amounts of glyceryl monooleate friction modifiers was evaluated according to ASTM D 6594. This evaluation measured the amount of lead concentration in the oil between 0 and 168 hours when heated at approximately 135°C. The amount of lead was measured by ICP using ASTM D5185 or an equivalent measurement. The lubricants evaluated included similar amounts of base oil, viscosity index modifier, succinimidyl dispersant, anti-wear additive, detergent, and defoamer. See Table 3 below. Figure 1 The results showed that lead corrosion increased with the increase in the treatment rate of friction modifier.

[0156] Table 3: Lead Corrosion

[0157] 0.0 40 0.2 318 0.4 707 0.6 879 0.8 980

[0158] Example 1

[0159] Different types of boron-containing compounds were evaluated to passivate lead corrosion associated with the carboxylic acid and / or hydroxyl groups of nitrogen-free organic friction modifiers (in this case, glyceryl monooleate) by pre-reacting the friction modifier with the boron-containing compound or by simply blending the boron-containing compound with the friction modifier in a lubricant at 70°C along with other lubricant additives. Similar to Comparative Example 1, the lubricants evaluated also included comparable amounts of base oil, viscosity index improver, succinimide dispersant, anti-wear additive, detergent, and defoamer. As with Comparative Example 1, lead corrosion was measured according to ASTM D6594, and lead concentration was measured according to ASTM D5185. In either case, the molar percentages of the boron-containing compound and glyceryl monooleate were equal. Surprisingly, as shown by comparing the results in Tables 4 and 5, and as... Figure 2 As shown, lead corrosion is comparable and / or improved if the friction modifier is not pre-reacted with the boron-containing composition before being blended with other lubricant components.

[0160] Table 4: Lubricants containing friction modifiers and boron compounds

[0161]

[0162] *The boron / 1 wt% GMO ratio is calculated, for example, by dividing 174.9 ppm boron by a GMO treatment rate of 0.56% to provide a boron ratio of 312.3 ppm boron / 1 wt% friction modifier.

[0163] **Lead corrosion (ΔPb) / 1 wt% GMO is calculated, for example, by dividing 70.0 ppm lead corrosion by a GMO treatment rate of 0.56 to provide a lead corrosion ratio of 125.0 ppm / 1 wt% friction modifier.

[0164] Table 5: Pre-reacted friction modifiers and boron-containing compound lubricants with a 1:1 molar ratio

[0165]

[0166] *Lead corrosion (ΔPb) per 1 wt% GMO is calculated, for example, 150.3 ppm lead corrosion divided by 0.6% GMO treatment rate to provide a lead corrosion ratio of 250.4 ppm / 1 wt% friction modifier.

[0167] As shown in Table 4 and Figure 3 As shown, the blend of friction modifier and boron compound can even produce a lubricant with lower lead corrosion than a lubricant without friction modifier. Furthermore, comparing the lead corrosion in Tables 4 and 5, in some cases, the blend of friction modifier and boron compound can even produce a lubricant with improved lead corrosion compared to a lubricant containing a friction modifier pre-boronized with the same boron compound. Figure 4 It is also shown that the method and the admixtures of the present invention form robust compositions in which lead corrosion is largely independent of the friction modifier treatment rate. For example, Figure 4 The results show that as the friction modifier treatment rate of the present invention increases, the lubricant of the present invention maintains a consistently low lead corrosion rate, while the lead corrosion of existing non-boronized friction modifiers tends to increase with the increase of the friction modifier treatment rate.

[0168] It should be noted that, unless explicitly and definitively limited to one indicator, the singular forms “a” and “described” as used in this specification and the appended claims include multiple indicators. Thus, for example, reference to “antioxidant” includes two or more different antioxidants. The term “comprising” and its grammatical variations as used herein are intended to be non-limiting, such that the description of an item in the list does not exclude other similar items that may be substituted for or added to the listed items.

[0169] For the purposes of this specification and the appended claims, unless otherwise stated, all figures and other numerical values ​​used in the specification and claims to express quantities, percentages or proportions should be understood to be modified by the term "about" in all cases. Therefore, unless indicated to the contrary, the numerical parameters set forth in the following specification and the appended claims are approximations that may vary depending on the desired characteristics sought to be obtained through this disclosure. To a minimum, and without attempting to limit the application of the equivalence principle to the scope of the claims, each numerical parameter should be interpreted at least according to the number of significant figures reported and by applying general rounding techniques.

[0170] It should be understood that each component, compound, substituent or parameter disclosed herein should be interpreted as disclosed for use alone or in combination with one or more of each other component, compound, substituent or parameter disclosed herein.

[0171] It should also be understood that each range disclosed herein should be interpreted as a disclosure of each specific value within the disclosed range having the same significant digits. Thus, for example, the range 1 to 4 should be interpreted as an explicit disclosure of the values ​​1, 2, 3, and 4, and any range of such values.

[0172] It should also be understood that each lower limit of each range disclosed herein should be interpreted as a combination of each upper limit of each range and each specific value within each range disclosed herein for the same component, compound, substituent, or parameter. Therefore, this disclosure should be interpreted as the disclosure of all ranges derived by combining each lower limit of each range with each upper limit of each range or with each specific value within each range, or by combining each upper limit of each range with each specific value within each range. That is, it should also be understood that this document also discusses any range between endpoint values ​​within a wide range. Therefore, the range 1 to 4 also means the range 1 to 3, 1 to 2, 2 to 4, 2 to 3, etc.

[0173] Furthermore, the specific amounts / values ​​of components, compounds, substituents, or parameters disclosed in this specification or examples should be interpreted as disclosures of a lower or upper limit of a range, and therefore can be combined with any other lower or upper limit or specific amount / value of the range of the same components, compounds, substituents, or parameters disclosed elsewhere in this disclosure to form the range of that component, compound, substituent, or parameter.

[0174] While specific embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that may not currently be foreseen or possibly not currently foreseen may arise in the applicant or other persons skilled in the art. Therefore, the appended claims, as filed and as may be amended, are intended to cover all such alternatives, modifications, variations, improvements, and substantial equivalents.

Claims

1. A method for reducing lead corrosion in an internal combustion engine lubricated with a lubricating oil composition, the method comprising supplying the internal combustion engine with a lubricating oil composition comprising a hydrocarbon-substituted succinimide dispersant obtained by reacting a hydrocarbon-substituted acylation agent with a nitrogen source, a nitrogen-free organic friction modifier having carboxylic acid and / or hydroxyl groups, and a major amount of a base oil or base oil blend having a lubricating viscosity, wherein the lubricating oil composition comprises a boron-containing compound selected from boric acid or borous acid, a blend of the hydrocarbon-substituted succinimide dispersant and the nitrogen-free organic friction modifier, and a blend of the two compounds. The boron-containing compound has the structure XB-(OH)2, wherein X is a hydroxyl group, a straight-chain or branched alkyl group, a cyclic hydrocarbon group, one or more aryl groups, a benzofuranyl group, a dibenzofuranyl group, or a combination thereof; and The lead corrosion rate is improved when using the admixture compared to a lubricant containing a friction modifier that has been pre-reacted with a boron-containing compound before being added to the lubricant.

2. The method according to claim 1, wherein the nitrogen-free organic friction modifier has a side hydroxyl group obtained from the reaction of fatty acids with alkanols; and / or wherein the hydrocarbon-substituted succinimide dispersant is boronized from a boron source separate from the boron-containing compound; and / or wherein the nitrogen-free organic friction modifier comprises a blend of monoesters and diesters of fatty acids.

3. The method of claim 2, wherein the lubricating oil composition comprises 250 ppm to 350 ppm of boron provided by the boron-containing compound per 1% by weight of the nitrogen-free organic friction modifier.

4. The method of claim 3, wherein the lubricating oil composition exhibits no more than 500 ppm of lead corrosion per 1 wt% of the nitrogen-free organic friction modifier, as measured according to ASTM D6594.

5. The method according to claim 2, wherein the boron-containing compound is borous acid, wherein X is a straight-chain or branched C1 to C10 group, one or more aryl, benzofuranyl, dibenzofuranyl or a combination thereof.

6. The method of claim 2, wherein the nitrogen-free organic friction modifier comprises a blend of monoesters and diesters of oleic acid.

7. The method of claim 6, wherein the nitrogen-free organic friction modifier comprises glyceryl monooleate.

8. The method of claim 1, wherein the lubricating oil composition comprises 100 ppm to 300 ppm of boron provided by the boron-containing compound, up to 10 wt% of the hydrocarbon-substituted succinimide dispersant, and up to 1 wt% of the nitrogen-free organic friction modifier.

9. A lubricating oil composition for reducing lead corrosion in internal combustion engines, the lubricating oil composition comprising: Hydrocarbon-substituted succinimide dispersants, nitrogen-free organic friction modifiers, and blends of boron-containing compounds; and base oils or base oil blends having a major amount of lubricating viscosity. in, The hydrocarbon-substituted succinimide dispersant is obtained by reacting a hydrocarbon-substituted acylation agent with a nitrogen source; wherein the nitrogen-free organic friction modifier has a carboxylic acid and / or a hydroxyl group; wherein the boron-containing compound is selected from boric acid or borous acid, wherein the boron-containing compound has the structure XB-(OH)2, wherein X is a hydroxyl group, a straight-chain or branched alkyl group, a cyclic hydrocarbon group, one or more aryl groups, a benzofuranyl group, a dibenzofuranyl group, or a combination thereof; and The lead corrosion of the lubricating oil composition is improved when using the blend compared to lubricants containing friction modifiers that have been pre-reacted with boron-containing compounds before being added to the lubricant.

10. The lubricating oil composition according to claim 9, wherein the nitrogen-free organic friction modifier has a side hydroxyl group obtained from the reaction of fatty acids with alkanols.

11. The lubricating oil composition of claim 10, wherein the lubricating oil composition comprises 250 ppm to 350 ppm of boron provided by the boron-containing compound per 1% by weight of the nitrogen-free organic friction modifier.

12. The lubricating oil composition of claim 11, wherein the lubricating oil composition exhibits no more than 500 ppm of lead corrosion per 1 wt% of the nitrogen-free organic friction modifier, as measured according to ASTM D6594.

13. The lubricating oil composition of claim 9, wherein the hydrocarbon-substituted succinimide dispersant is boronized from a boron source separate from the boron-containing compound; and / or wherein the nitrogen-free organic friction modifier comprises a blend of monoesters and diesters of fatty acids.

14. The lubricating oil composition according to claim 13, wherein the boron-containing compound is borous acid, wherein X is a straight-chain or branched C1 to C10 group, one or more aryl, benzofuranyl, dibenzofuranyl or a combination thereof.

15. The lubricating oil composition of claim 9, wherein the lubricating oil composition comprises 100 ppm to 300 ppm of boron provided by the boron-containing compound, up to 10 wt% of the hydrocarbon-substituted succinimide dispersant, and up to 1 wt% of the nitrogen-free organic friction modifier.

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