Alkaline ashless additives and lubricating compositions comprising alkaline ashless additives

Abstract

The disclosed technology relates to a lubricating composition comprising: an oil of lubricating viscosity, and a ashless basic amine additive selected from a secondary amine containing an alpha-carbon aromatic substitution. The basic secondary amine additive used in the disclosed technology lubricating oil imparts basicity as measured by total base number (TBN) without the addition of sulfated ash. The lubricating oil containing the basic secondary amine additive of the disclosed technology simultaneously achieves seal compatibility, deposit and corrosion control.

Description

Technical Field

[0001] The technology disclosed in this invention relates to additives for lubricating oil compositions, lubricating oils containing these additives, and methods for lubricating engines. The additives used in the lubricating oils of the disclosed technology impart alkalinity as measured by total base number (TBN) without the addition of sulfated ash, phosphorus, and sulfur. These additives reduce crankcase corrosion and have improved compatibility with fluorinated elastomer seals. Background Technology

[0002] Lubricating oil compositions for internal combustion engines comprise a base oil having a lubricating viscosity as the primary component and various lubricating oil additives to improve oil performance. These additives improve detergency, reduce engine wear, provide stability against heat and oxidation, inhibit corrosion, and enhance engine efficiency by reducing friction. Internal combustion engines produce acidic and oxidizing byproducts due to the incomplete combustion of hydrocarbon fuels. These byproducts have detrimental effects in engine oils and also in the engine. For example, byproducts can oxidize hydrocarbons present in the lubricating oil, producing carboxylic acids and other oxygenated compounds. These oxidized and acidic hydrocarbons cause engine corrosion, wear, and deposit problems. Lubricants must be able to neutralize the acidic substances produced by combustion.

[0003] Historically, alkaline additives have been added to lubricants to neutralize such byproducts, thereby reducing their harmful effects on lubricants and engines. For some time, highly alkaline hydrocarbon sulfonic acid detergents containing metallic bases (such as oxides or carbonates of calcium or magnesium) have been used as acid removers, neutralizing acidic byproducts and protecting lubricants and engines. The neutralizing function of highly alkaline detergents is particularly important for extended oil drain intervals, during which reduced detergent levels can compromise oil life. However, as measured by sulfated ash, highly alkaline detergents can carry significant amounts of metals. When lubricating oils containing highly alkaline detergents are consumed, these metals form ash deposits and residues. Combining highly alkaline metallic detergents with anti-wear agents such as zinc dialkyl dithiophosphate (ZDDP) can increase sulfated ash, phosphorus, and sulfur (SAPS) byproducts, which can interfere with the performance of engine particulate filters and emission catalysts. New industrial upgrades in diesel engine and bus lubricants are continuously reducing restrictions on the amount of SAPs, and consequently, on the amount of highly alkaline detergents and / or anti-wear agents formulated into the oil. However, by minimizing the presence of highly alkaline detergents and anti-wear agents, the alkalinity of the oil and its ability to neutralize acidic byproducts formed during combustion are consequently reduced, ultimately compromising oil life and requiring shorter replacement intervals.

[0004] Oil life can be extended by increasing the oil's total basicity (typically expressed as total base number (TBN)). However, the challenge lies in delivering TBN without increasing SAPS or highly alkaline compounds that induce corrosion. Certain TBN-promoting compounds, such as amine compounds, have been used to help neutralize acids formed during combustion in the engine. However, some of these amine compounds can have adverse effects on elastomeric seals. It is believed that certain amines cause defluorination of the fluoropolymer backbone. The resulting unsaturations are easily oxidized, leading to loss of physical properties, seal degradation, and eventual failure. Seal failure impairs engine performance, increases the likelihood of engine damage, and results in unacceptable oil leaks from the crankcase environment.

[0005] However, basic amine additives have been studied as alternatives to highly basic metal detergents containing ash, such as alkyl and aromatic amines. Basic amine additives, such as succinimidyl dispersants, contain polyamine groups that provide a source of basicity. However, as mentioned above, such amines are believed to induce defluorination in fluorinated elastomer sealing materials. Generally, the basicity content or TBN of lubricants can only be moderately increased by amine dispersants before seal deterioration and / or corrosion become significant problems, thus limiting the amount of TBN that can be provided by such additives.

[0006] In the field of lubricant additives, two commonly used methods exist for measuring alkalinity. Total base number (TBN) can be measured using ASTM D2896, which titrates both strong and weak bases. On the other hand, ASTM D4739 titrates strong bases. It is known that amines titrated with ASTM D2896 are more corrosive to fluoropolymer seals, while amines titrated with D4739 are less corrosive. Therefore, many lubricant applications require TBN titrated using ASTM D4739.

[0007] Succinimid dispersants have a relatively high basic nitrogen content, expressed as TBN (ASTM D2896). Generally, a higher nitrogen content provides better dispersibility and deposit control. However, the objective is to deliver a high TBN, as measured by ASTM D4739, without compromising seal compatibility.

[0008] U.S. Patent 9,441,180 discloses anthranilate compounds as additives in lubricants. This document discloses compositions that supposedly deliver ashless alkali into lubricants as basic amine additives without adversely affecting seal compatibility. Examples report product TBN values ​​of 150 to 188, as measured by D2896 (including weakly basic titrations).

[0009] U.S. Patent 9,783,756 relates to N-monoalkyl-substituted γ-amino esters. While the γ-amino esters disclosed in this invention are titrated to ASTM D4739, they are less durable in oil life cycles requiring shorter drain intervals.

[0010] It is desirable to provide lubricant compositions with high TBN levels using TBN additives that do not contribute to SAPS. Since highly alkaline additives are known to induce corrosion and reduce the compatibility of lubricant compositions with fluorinated elastomer seals used in engines, it is advantageous to provide additives that do not induce corrosion and do not adversely affect seal compatibility. Furthermore, the demand for improved fuel economy, lower viscosity lubricants such as 0W and 5W, and Grade 30 lubricants is becoming increasingly desirable. To allow for easier formulation and reduced viscosity, the amount of polymer introduced by the additives should ideally be minimized.

[0011] The additives disclosed in this invention solve the problem of imparting strong alkalinity (as measured by ASTM D4739) to lubricants without introducing additional metal content in the form of SAPS, and without causing degradation of fluoroelastomer seals, as measured according to the specifications set forth in (“MB” - Mercedes Benz Seals) DBL6674-FKM. This is achieved by providing non-polymerized N-aryl α-carbonyl functionalized amine additives, as described more fully herein. As further stated, this technology provides the ability to impart relatively high TBN levels to lubricants while maintaining low SAPS levels as required by increasingly stringent government regulations, thus protecting seal performance and compatibility and mitigating corrosion of metal engine components. Summary of the Invention

[0012] In one aspect, the present technology relates to a lubricating oil composition for internal combustion engines, comprising one or more alkaline ashless additives for improving the TBN of the composition without introducing SAPS.

[0013] In one related aspect, the present technology relates to a lubricating oil composition for an internal combustion engine, comprising a major amount of an oil having a lubricating viscosity and an effective amount of one or more alkaline ashless amine additives, which are suitable for increasing the TBN of the composition without introducing SAPS and are compatible with fluoroelastomer seals.

[0014] In one related aspect, the present technology relates to a lubricating oil composition for an internal combustion engine, comprising a major amount of an oil having a lubricating viscosity and an effective amount of one or more alkaline ashless amine additives, which are suitable for increasing the TBN of the composition without introducing SAPS, are compatible with fluoroelastomer seals, and reduce corrosion of internal engine components.

[0015] In one related aspect, the present technology provides a method for preparing a high TBN lubricating oil composition for internal combustion engines having a reduced SAPS content, the high TBN lubricating oil composition comprising one or more basic ashless additives selected from secondary amines containing α-carbon aromatic substituted amines, the basic ashless additives being found to be useful as additives for increasing the TBN of the lubricating oil composition without introducing SAPS.

[0016] In one related aspect, the present technology provides the use of one or more secondary amines containing α-carbon aromatic substituted amines as TBN sources for ashless lubricating oil compositions.

[0017] In one related aspect, this technology provides a lubricating oil composition comprising one or more basic ashless additives selected from secondary amines containing α-carbon aromatic substituted compounds, which meets increasingly stringent standards for engine lubricant seal compatibility testing performance specifications of ASTM, DIN, ISO, CEC and other local and commercial OEM standards.

[0018] In one related aspect, the present technology provides a method for improving the wear life and other tribological properties of an internal combustion engine by adding an effective amount of one or more secondary amines containing α-carbon aromatic substituted compounds to a lubricating oil composition, and circulating the added oil having a lubricating viscosity through the internal combustion engine under normal engine operating conditions.

[0019] In one related aspect, the present technology provides an additive lubricating oil composition suitable for reducing engine deposits and corrosion, while improving TBN and preventing or mitigating the deterioration of elastomeric seals in internal combustion engines, said composition comprising:

[0020] a) Oils with lubricating viscosity, and

[0021] b) One or more secondary amines containing α-carbon aromatic substitutions.

[0022] In one aspect, the technology disclosed in this invention relates to a method for improving TBN, as measured by ASTM D4739. This method includes the step of adding an ashless amine additive selected from α-carbon aromatic substituted secondary amines to an oil having a lubricating viscosity.

[0023] In another related aspect, this technology relates to the use of one or more secondary amines containing α-carbon aromatic substitutions for increasing TBN, reducing SAPS, mitigating corrosion, and improving the seal compatibility of lubricating oils in internal combustion engines. Detailed Implementation

[0024] The following describes various aspects of the present technology. Various modifications, adaptations, or variations of these exemplary aspects described herein will become apparent to those skilled in the art as disclosed. It should be understood that all such modifications, adaptations, or variations that rely on the teachings of the present technology and have been improved in the art through these teachings are considered to be within the scope and spirit of the disclosed technology.

[0025] The technology disclosed in this invention provides a lubricating oil composition comprising:

[0026] a) Oils with lubricating viscosity; and

[0027] b) An additive selected from one or more secondary amines containing α-carbon aromatic substitutions, said additive being present in the internal combustion engine in an effective amount to increase TBN, reduce SAPS, mitigate corrosion, and improve seal compatibility.

[0028] The secondary amine additives disclosed in this invention are typically present in lubricants or lubricant formulations, one component of which is an oil having lubricating viscosity. The oil having lubricating viscosity is also called a base oil, and can be selected from any base oil in Group IV of the American Petroleum Institute (API) Base Oil Interchangeability Guidelines.

[0029] Oil with lubricating viscosity

[0030] Oils with lubricating viscosity may include, for example, natural and synthetic oils; oils derived from hydrocracking, hydrogenation, and hydrorefining; unrefined oils; refined and refined oils, and mixtures thereof. Oils with lubricating viscosity may also be defined as specified in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines.

[0031] Unrefined oils are oils that are typically obtained directly from natural or synthetic sources without (or with minimal) further purification. Refined oils are similar to unrefined oils, except that they have undergone further processing in one or more purification steps to improve one or more properties. Purification techniques are known in the art and include solvent extraction, double distillation, acid or alkali extraction, filtration, percolation, etc. Re-refined oils, also known as regenerated oils or reprocessed oils, are obtained by methods similar to those used to obtain refined oils and are often further processed by techniques involving the removal of waste additives and oil decomposition products. Natural oils that can be used to prepare the lubricants of this invention include animal and vegetable oils (e.g., castor oil), mineral lubricants (such as liquid petroleum), and solvent-treated or acid-treated alkanes, cycloalkanes, or mixed alkane-cycloalkanes type mineral lubricants, as well as oils derived from coal or shale or mixtures thereof. Synthetic lubricants are useful and include hydrocarbon oils such as polymeric olefins and interpolymeric olefins (e.g., polybutene, polypropylene, propylene isobutylene copolymers); poly(1-hexene), poly(1-octene), poly(1-decene), and mixtures thereof; alkylbenzenes (e.g., dodecylbenzene, tetradecylbenzene, dinonylbenzene, di-(2-ethylhexyl)benzene); polyphenylene (e.g., biphenyl, terphenyl, alkylated polyphenylene); diphenylalkanes, alkylated diphenylalkanes, alkylated diphenyl ethers, and alkylated diphenyl sulfides, and their derivatives, analogs, and homologues, or mixtures thereof. Other synthetic lubricants include polyol esters (such as Priolube.RTM.3970), diesters, phosphoric acid-containing liquid esters (e.g., tricresyl phosphate, trioctyl phosphate, and diethyl decanephosphonic acid), or polytetrahydrofurans. Synthetic oils can be produced by the Fischer-Tropsch reaction and are typically hydroisomerized Fischer-Tropsch hydrocarbons or waxes. In one respect, oil can be prepared through Fischer-Tropsch gas-to-oil synthesis processes and other gas-to-oil methods.

[0032] Oils with lubricating viscosity can also be defined as specified in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. The five base oil categories are as follows: Group I (sulfur content >0.03 wt% and / or <90 wt% saturated oil, viscosity index 80-120); Group II (sulfur content ≤0.03 wt% and ≥90 wt% saturated oil, viscosity index 80-120); Group III (sulfur content ≤0.03 wt% and ≥0.90 wt% saturated oil, viscosity index ≥120); Group IV (all polyalphaolefins (PAOs)); and Group V (all other oils not included in Groups I, II, III, or IV). Oils with lubricating viscosity include API Group I, II, III, IV, and V oils, or mixtures thereof. Typically, oils with lubricating viscosity are API Group I, II, III, and IV oils, or mixtures thereof. Alternatively, oils with lubricating viscosity are typically API Group II, III, and IV oils, or mixtures thereof. In some respects, the oils with lubricating viscosity used in the lubricant compositions include Group III base oils.

[0033] The lubricating oil composition disclosed in this invention comprises a major amount of an oil having lubricating viscosity and a minor amount of one or more N-aryl α-carbonyl functional amines. The amount of oil having lubricating viscosity is typically the balance remaining after subtracting the sum of the amounts of additives (including one or more N-aryl α-carbonyl functional amines as described below) from 100% by weight.

[0034] Alkaline ashless additives

[0035] The main additive included in the lubricating oil composition disclosed in this invention is an alkaline ashless additive selected from secondary amines containing α-carbon aromatic substitutions. α-carbon aromatic substitution means that at least one of the two α-carbon atoms adjacent to the amine nitrogen contains at least one aromatic substituent.

[0036] Throughout this specification, the term "aromatic" refers to an unsaturated aromatic carbocyclic group having a single ring (e.g., phenyl) or multiple fused rings (e.g., naphthyl, anthracene, and phenanthrene). In one aspect, an aromatic group is an allotropic ring (without heteroatoms) containing 6 to 14 ring carbon atoms. The term "aromatic" includes both substituted and unsubstituted aromatic compounds. Exemplary substituents include, but are not limited to, C1-C... 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations.

[0037] Aromatic groups include "heteroaromatic groups," which are unsaturated aromatic carbocyclic groups having 2 to 10 cyclic carbon atoms and at least one cyclic heteroatom, including but not limited to heteroatoms selected from nitrogen, oxygen, and sulfur. Heteroaromatic groups may have a single ring (e.g., pyridyl, furanyl) or multiple fused rings (e.g., indoleazinyl, benzothiopheneyl), which may or may not be aromatic.

[0038] In one aspect, the aromatic substituent is a phenyl group, which can be substituted or unsubstituted. In another aspect, the phenyl substituent is independently C1-C2. 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations of substitutions.

[0039] Throughout this specification and throughout the description, the term "hydrocarbon" is used in its common sense, as is well known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly bonded to at least one of the two α-carbon atoms adjacent to the nitrogen atom of the amine. In one aspect, a hydrocarbon group comprises a portion containing 1 to 24 carbon atoms, or 2 to 16 carbon atoms, or 3 to 12 carbon atoms, or 4 to 8 carbon atoms. The hydrocarbon group may be substituted or unsubstituted. Substituents include alkyl, alkenyl, amino, hydroxyl, alkoxy, and halogen groups. In one aspect, the hydrocarbon group is C1 to C2. 24 alkyl.

[0040] The term "alkyl" refers to and includes saturated straight-chain and branched hydrocarbon structures, as well as combinations thereof. Alkyl groups are those having 1 to 24, 2 to 16, 3 to 12, or 4 to 8 carbon atoms. When naming alkyl groups with a specific number of carbon atoms, the aim is to encompass and describe all geometric isomers having that number of carbon atoms; for example, "propyl" includes n-propyl and isopropyl, and "butyl" includes n-butyl, sec-butyl, isobutyl, and tert-butyl. Examples of this term include groups such as methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, pentyl, neopentyl, hexyl, heptyl, octyl, etc.

[0041] The term "alkenyl" refers to an unsaturated hydrocarbon group having at least one olefinic unsaturated site (i.e., having at least one carbon-carbon double bond). In one aspect, an alkenyl group contains 2 to 24, 2 to 16, 3 to 12, or 4 to 8 carbon atoms. Examples of alkenyl groups include, but are not limited to, vinyl, propenyl, octenyl, nonenyl, and oleoyl.

[0042] The term "alkynyl" refers to an unsaturated hydrocarbon group having at least one alkynyl unsaturated site (i.e., having at least one carbon-carbon triple bond). In one aspect, an alkynyl group contains 2 to 24, 2 to 16, 3 to 12, or 4 to 8 carbon atoms. Examples of alkynyl groups include, but are not limited to, ethynyl, propynyl, and butynyl.

[0043] In one aspect, the alkaline ashless additive disclosed in this invention is a secondary amine, which contains:

[0044] i) At least two aromatic substituents attached to either of the two α-carbons adjacent to the amine nitrogen;

[0045] ii) up to three aromatic substituents attached to two α-carbons, and up to two aromatic substituents on a single α-carbon;

[0046] iii) An optional hydrocarbon group on one or two α-carbons;

[0047] iv) At most one hydrogen substituent on any hydrocarbon-substituted α-carbon.

[0048] In one aspect, the alkaline ashless additive disclosed in this invention is a secondary amine having a first α-carbon and a second α-carbon bonded to an amine nitrogen, wherein each of the first α-carbon and the second α-carbon independently comprises a substituent selected from hydrogen, aromatic groups, hydrocarbon groups, and combinations thereof, wherein at least two aromatic groups are located at either or both of the first α-carbon and the second α-carbon, but not exceeding a total of two aromatic groups located on either the first α-carbon and the second α-carbon, and wherein the total number of aromatic groups located on the first α-carbon and the second α-carbon cannot exceed three, and wherein each of the first α-carbon and the second α-carbon respectively occupied cannot contain two hydrogen substituents unless an aromatic substituent is present.

[0049] In one related aspect, the first α-carbon contains two aromatic substituents, and the second α-carbon contains one aromatic substituent and one hydrocarbon substituent.

[0050] In one related aspect, the first α-carbon contains two aromatic substituents, and the second α-carbon contains two hydrocarbon substituents and no aromatic substituents.

[0051] In one related aspect, the first α-carbon contains an aromatic substituent and a hydrocarbon substituent, and the second α-carbon contains an aromatic substituent and a hydrocarbon substituent.

[0052] In one related aspect, the first α-carbon contains an aromatic substituent and a hydrocarbon substituent, and the second α-carbon contains an aromatic substituent and does not contain a hydrocarbon substituent.

[0053] In one related aspect, the aromatic group is independently selected from substituted and unsubstituted phenyl, naphthyl, anthracene, and phenanthrene groups.

[0054] In one related aspect, the aromatic group is selected from substituted and unsubstituted phenyl groups, which can be independently converted from C1 to C2. 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations of substitutions.

[0055] In one related aspect, the hydrocarbon substituent is selected from alkyl groups having 1 to 24, 2 to 16, 3 to 12, or 4 to 8 carbon atoms.

[0056] In one related aspect, the hydrocarbon group is an alkyl group selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and combinations thereof.

[0057] In one aspect, the alkaline ashless additive disclosed in this invention is a secondary amine, typically represented by the schematic structure (I):

[0058]

[0059] R1 to R6 are selected from hydrogen, C6-C 14 Aromatic groups, C1-C 24 Hydrocarbon group, or C2 to C 16 Hydrocarbon group, or C3 to C 12 A hydrocarbon group, or a combination of C4 to C8 hydrocarbon groups, wherein at least two of R1 to R6 represent an aromatic group, and no more than two of R1 to R3 or R4 to R6 can be aromatic at the same time, and the total number of aromatic groups represented by R1 to R6 cannot exceed three, and any two of R1 to R3 cannot be hydrogen at the same time unless one of R1 to R3 is an aromatic group, or any two of R4 to R6 cannot be hydrogen at the same time unless one of R4 to R6 is an aromatic group.

[0060] In one relevant aspect, R1 and R2 are aromatic, R3 is hydrogen, R4 is aromatic, R5 is hydrogen, and R6 is C1-C. 24 Hydrocarbon group.

[0061] In one relevant aspect, R1 and R2 are aromatic, R3 is hydrogen, and R4 and R5 are independently selected from C1-C2. 24It has a hydrocarbon group, and R6 is hydrogen.

[0062] In one relevant aspect, R1 is aromatic, R2 is hydrogen, and R3 is selected from C1-C2. 24 The hydrocarbon group has R4 as hydrogen, and R5 and R6 are independently selected from C1-C2. 24 Hydrocarbon group.

[0063] In one relevant aspect, R1 is aromatic, R2 is hydrogen, and R3 is selected from C1-C2. 24 The hydrocarbon group has R4 as an aromatic group, R5 as hydrogen, and R6 selected from C1-C6. 24 Hydrocarbon group.

[0064] In one relevant aspect, R1 is aromatic, R2 is hydrogen, and R3 is selected from C1-C2. 24 Hydrocarbon group, R4 is aromatic, R5 and R6 are hydrogen.

[0065] In one related aspect, the aromatic group is independently selected from substituted and unsubstituted phenyl, naphthyl, anthracene, and phenanthrene groups.

[0066] In one related aspect, the aromatic group is selected from substituted and unsubstituted phenyl groups, which can be independently converted from C1 to C2. 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations of substitutions.

[0067] In one related aspect, the hydrocarbon substituent is selected from alkyl groups having 1 to 24, 2 to 16, 3 to 12, or 4 to 8 carbon atoms.

[0068] In one related aspect, the hydrocarbon group is an alkyl group selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and combinations thereof.

[0069] In one aspect, the alkaline ashless additive disclosed in this invention is a secondary amine represented by the schematic structure (II):

[0070]

[0071] R3 and R6 are independently selected from hydrogen and methyl, and R is independently selected from hydrogen, C1-C. 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations.

[0072] In one aspect, the alkaline ashless additive disclosed in this invention is a secondary amine represented by the schematic structure (III):

[0073]

[0074] R6 is selected from hydrogen and methyl, and R is independently selected from hydrogen, C1-C. 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations.

[0075] In one aspect, the alkaline ashless additive disclosed in this invention is a secondary amine represented by the schematic structure (IV):

[0076]

[0077] R4 and R5 are independently selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and octyl, and R is independently selected from hydrogen, C1-C2, C2 ... 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations.

[0078] The alkaline ashless additives disclosed in this invention can be synthesized via conventional synthetic routes well known to those skilled in the art, such as, for example, by reductive amination of a carbonyl-containing compound (such as an aldehyde or ketone), or by alkylation of a primary amine to obtain the desired secondary amine product. In the preparation of the alkaline ashless additives disclosed in this invention, reductive amination requires reacting a primary amine with a carbonyl-containing compound in the presence of a reducing agent (such as sodium triacetoxyborohydride (STAB)).

[0079] Alternatively, the desired secondary amine product can be obtained by alkylating the primary amine with an alkyl halide or an aromatic-substituted alkyl halide.

[0080] In one aspect, based on the weight of the total lubricating composition, the amount (treatment rate) of the alkaline ashless secondary amine additive of the present invention, as a component of the oil having lubricating viscosity, is in the range of about 0.1 wt% to about 6 wt%, or about 0.2 wt% to about 4 wt%, or about 0.25 wt% to about 2 wt%, or about 0.3 wt% to about 1 wt%. This substance can also be used alone in concentrated form or in combination with other additives and a smaller amount of oil. In the concentrated form, the amount of the substance can be two to ten times the aforementioned concentration. The concentrated form can be used as a post-treatment additive to maintain the TBN between predetermined oil discharge intervals.

[0081] In lubricants, the amount of basic ashless secondary amine additive may be suitable to provide the lubricant with a TBN of at least 0.3, or 0.5, or 0.7, or 1.0, or 1.2, or 1.5 as measured by ASTM D4739, and in some aspects, at most 3, or 4, or 5 TBN. In one aspect, the basic ashless secondary amine delivers an ashless TBN of about 0.5 mg KOH / g to about 8 mg KOH / g, or about 0.7 mg KOH / g to about 7 mg KOH / g, or about 0.7 mg KOH / g to about 5 mg KOH / g, or about 0.8 mg KOH / g to about 4 mg KOH / g, or about 0.8 mg KOH / g to about 2.5 mg KOH / g, or about 0.8 mg KOH / g to about 1.5 mg KOH / g as measured by ASTM D4739. The increase in TBN is determined relative to the same composition without the basic ashless secondary amine additive.

[0082] As used herein, the term TBN refers to the total base number, expressed as measured in mg KOH / g sample, as determined by ASTM D2896 or ASTM D4739.

[0083] In some aspects, lubricants employing the technology of the present invention may have a total TBN of at least 5 or at least 6, 7, 8, 9 or 10 from all sources, and may have a TBN of up to (or less than) 25, 20 or 15. In some aspects, lubricants employing the technology of the present invention may have a sulfated ash content of less than 1.5% or less than 1.3% or 1.0% or 0.8% (as measured by ASTM D874) or may be at least 0.05% or 0.1%.

[0084] In addition to the alkaline, ashless secondary amine substances disclosed in this invention, the lubricating oil composition may optionally contain other performance additives. These other performance additives may include at least one of the following: detergents, metal passivators, dispersants, viscosity modifiers, friction modifiers, anti-wear agents, corrosion inhibitors, dispersants, viscosity modifiers, extreme pressure agents, anti-wear agents, antioxidants, foam inhibitors, demulsifiers, pour point depressants, sealing swelling agents, color stabilizers, and mixtures thereof. Typically, a fully formulated lubricating oil will contain one or more of these performance additives. Performance additives are not necessarily limited to those discussed below.

[0085] Cleaning agent

[0086] Detergents are typically highly basic substances, or called highly basic or superbasic salts, and are usually homogeneous Newtonian systems. Based on the stoichiometry of the metal and the detergent anion, their metal content exceeds the amount of metal present when used for neutralization. The amount of excess metal is usually expressed as a metal ratio, that is, the ratio of the total equivalent of the metal to the equivalent of the acidic organic compound. Highly basic substances are prepared by reacting an acidic substance (such as carbon dioxide) with an acidic organic compound, an inert reaction medium (such as mineral oil), a stoichiometric excess of a metal base or quaternary ammonium base, and a accelerator (such as phenol or alcohol). The acidic organic substance typically has a sufficient number of carbon atoms to provide oil solubility.

[0087] Highly alkaline detergents can be characterized by their total basicity (TBN), which is the amount of strong acid required to neutralize the alkalinity of all substances, expressed as mg KOH / g sample. Since highly alkaline detergents are typically supplied in the form of diluted oil, for the purposes of this literature, the TBN will be recalculated (when involving detergents or specific additives) to an oil-free basis. Some available detergents may have TBNs of 100 to 800, 150 to 750, or 400 to 700.

[0088] Metal compounds that can be used to prepare basic metal salts are generally any Group 1 or Group 2 metal compound (CAS version of the periodic table). Examples include alkali metals such as sodium, potassium, lithium, copper, magnesium, calcium, barium, zinc, and cadmium. In one aspect, the metal is sodium, magnesium, or calcium. The anionic moiety of the salt can be hydroxide, oxo, carbonate, borate, or nitrate. The lubricant compositions of the present invention may contain one or more of the following highly alkaline detergents.

[0089] In one respect, lubricants may contain highly basic sulfonate detergents. Suitable sulfonic acids include sulfonic acids and thiosulfonic acids, including mononuclear or polynuclear aromatic or cyclic aliphatic compounds. Some oil-soluble sulfonates may be derived from R... 10 -T(SO3 - ) a or R 11 (SO3 - ) b This indicates that a and b are each at least one; T is a cyclic nucleus, such as benzene or toluene; R 10 Aliphatic groups, such as alkyl, alkenyl, alkoxy, or alkoxyalkyl; (R 10 )-T typically contains at least 15 carbon atoms in total; R 3 These are aliphatic hydrocarbon groups that typically contain at least 15 carbon atoms. Groups T and R... 10 and R 11It may also contain other inorganic or organic substituents. In one aspect, the sulfonate detergent may be a predominantly straight-chain alkylbenzene sulfonate detergent with a metal ratio of at least 8, as described in paragraphs

[0026] to

[0037] of U.S. Patent 7,407,919. In some aspects, the straight-chain alkyl group may be attached to the benzene ring at any position along the straight chain of the alkyl group, but typically at the 2, 3, or 4 position of the straight chain, and in some cases, predominantly at the 2 position.

[0090] Another highly alkaline substance is the highly alkaline phenolate detergent. Phenols that can be used to prepare phenolate detergents can be derived from (R... 15 ) a -Ar-(OH) b It means that R 15 It is an aliphatic hydrocarbon group with 4 to 400, 6 to 80, 6 to 30, 8 to 25, or 8 to 15 carbon atoms; Ar is an aromatic group, such as benzene, toluene, or naphthalene; a and b are each at least one, and the sum of a and b is the number of substituted hydrogens on the aromatic nucleus of at most Ar, such as 1 to 4 or 1 to 2. For each phenolic compound, R 15 The group typically provides an average of at least 8 aliphatic carbon atoms. Phenolic detergents are sometimes also provided as a type of sulfur-bridged detergent.

[0091] In one respect, highly alkaline substances are highly alkaline salicylates. Highly alkaline salicylates are typically based on highly alkaline magnesium salts of salicylates derivatives. A general example of such salicylates derivatives can be represented by formula (V):

[0092]

[0093] Where Z is -CHO or -CH2OH, Y is -CH2- or -CH2OCH2-, and the -CHO group typically contains at least 10 mol% of the Z and Y groups; M is hydrogen, ammonium, or a metal ion in one valence state (i.e., if M is multivalent, one of the valence states is satisfied by the structure shown, while other valence states are satisfied by other types such as anions or by another instance of the same structure), R 17 It is a hydrocarbon group having 1 to 60 carbon atoms, m is 0 to usually 10, and each p is independently 0, 1, 2 or 3, provided that at least one aromatic ring contains R. 17 Substituents and all R 17 The total number of carbon atoms in the group is at least 7. When m is 1 or greater, one of the Z groups may be hydrogen. In one aspect, M is a Mg ion in a single valence state or a mixture of Mg and hydrogen. Salicylol detergents are disclosed in more detail in U.S. Patent 6,310,009, with particular reference to its synthesis method (column 8 and Example 1) and preferred amounts of various Z and Y groups (column 6).

[0094] Salicylate detergents are highly alkaline substances that can be represented by compounds containing at least one unit of formula (VI) or formula (VII):

[0095]

[0096] The compounds represented by formulas (VI) and (VII) each have end groups represented by formulas (VIII) and (IX):

[0097]

[0098] These groups are linked by a divalent bridging group A, which can be the same or different. In formulas (VI) to (IX), R 20 It can be hydrogen, a hydrocarbon group, or a metal ion or ammonium ion in one valence state; R 25 It is a hydroxyl or hydrocarbon group, and j is 0, 1, or 2; R 23 It is a hydrogen, hydrocarbon group, or heterosubstituted hydrocarbon group; or R 21 It is a hydroxyl group, and R 22 and R 24 Independently a hydrogen, hydrocarbon group, or heterosubstituted hydrocarbon group, or R 22 and R 24 Both are hydroxyl groups, and R 21 It can be a hydrogen group, a hydrocarbon group, or a heterosubstituted hydrocarbon group; the prerequisite is that R 21 R 22 R 23 and R 24 At least one of the components is a hydrocarbon group containing at least 8 carbon atoms; and the molecule contains, on average, at least one of unit (VI) or (VIII) and at least one of unit (VII) or (IX), and the ratio of the total number of units (VI) and (VIII) to the total number of units (VII) and (IX) in the composition is from 0.1:1 to 2:1. The divalent bridging group "A" may be the same or different each time it appears, including -CH2- and -CH2OCH2-, either of which may be derived from formaldehyde or formaldehyde equivalents (e.g., paraformaldehyde, formalin).

[0099] Salicylate alkoxide derivatives and their preparation methods are described in more detail in U.S. Patent No. 6,200,936 and PCT Publication WO 01 / 56968. It is believed that the salicylate alkoxide derivatives have a predominantly linear rather than macrocyclic structure, but both structures are intended to be encompassed by the term "salicylate alkoxide".

[0100] Glyoxylate detergents are similar highly alkaline substances based on anionic groups, and in one respect, they can have a structure represented by formula (X):

[0101]

[0102] Where R 30 Independently, it is an alkyl group containing at least 4 or 8 carbon atoms, provided that all R 30 The total number of carbon atoms in the substituents is at least 12, 16, or 24. Alternatively, each R 30 The substituents can be olefin polymer substituents. The acidic substance used to prepare highly basic glyoxylate detergents can be a condensation product of a hydroxy aromatic substance (such as a hydrocarbon-substituted phenol) and a carboxylic acid reactant (such as glyoxylic acid or another ω-oxoalkyl acid). Highly basic glyoxylate detergents and methods for their preparation are disclosed in more detail in U.S. Patent 6,310,011 and the references cited therein.

[0103] Highly alkaline detergents can also be highly alkaline salicylates, such as substituted alkali metal salts, alkaline earth metal salts, or ammonium salts of salicylic acid. The salicylic acid can be hydrocarbon-substituted, wherein each substituent contains an average of at least 8 carbon atoms / substituent and 1 to 3 substituents / molecule. The substituents can be polyolefin substituents. In one aspect, the hydrocarbon substituent group contains 7 to 300 carbon atoms and can be an alkyl group with a molecular weight of 150 to 2000. Highly alkaline salicylate detergents and methods for their preparation are disclosed in U.S. Patents 4,719,023 and 3,372,116.

[0104] Other highly alkaline detergents may include those having a Mannich base structure, as disclosed in U.S. Patent 6,569,818.

[0105] In some respects, the hydrocarbon substituents on the hydroxyl-substituted aromatic rings of the aforementioned detergents (e.g., phenolates, salicylates, salicylates, glyoxylates, or salicylates) contain no or substantially no C 12 Aliphatic hydrocarbon groups (e.g., less than 1 wt%, 0.1 wt%, or 0.01 wt% of substituents are C) 12 (Aliphatic hydrocarbon substituents). In some respects, such hydrocarbon substituents contain at least 14 or at least 18 carbon atoms.

[0106] In the formulations of this technology, on an oil-free basis, the amount of highly alkaline detergent is typically at least 0.6% by weight, or from 0.7% by weight to 5% by weight, or from 1% by weight to 3% by weight. A single detergent or multiple detergents may be present.

[0107] The amount of the highly alkaline detergent can also be expressed by the amount of metal, particularly alkaline earth metal, delivered to the lubricating composition by the detergent. In one aspect, the highly alkaline detergent is present in an amount delivering 500 ppm to 3000 ppm, or 800 ppm to 2400 ppm of alkaline earth metal, or a combination of alkaline earth metals, by weight to the composition. The highly alkaline detergent may be present in an amount delivering 1000 ppm to 2500 ppm of calcium, or in an amount delivering 400 ppm to 2500 ppm of magnesium, or a combination thereof, to the composition. In one embodiment, the lubricating composition comprises at least 400 ppm of magnesium and no more than 1500 ppm of calcium from the highly alkaline detergent.

[0108] The amount of highly alkaline detergent can also be expressed by the amount of sulfated ash delivered to the lubricating composition by the detergent. In one aspect, one or more highly alkaline detergents are present in an amount delivering 0.05% to 1.2% by weight, or 0.25% to 0.85% by weight, or 0.15% to 0.5% by weight of sulfated ash to the lubricating composition. In another aspect, the highly alkaline detergent is present in an amount delivering less than 1% by weight, or less than 0.75% by weight, or less than 0.45% by weight of sulfated ash to the lubricating composition.

[0109] dispersant

[0110] Dispersants are well-known in the lubricant industry and mainly include those known as ashless dispersants and polymeric dispersants. Ashless dispersants are named as such because, when used, they are metal-free and therefore generally do not contribute sulfated ash when added to lubricants. However, once added to lubricants containing metals, they can, of course, interact with the surrounding metals. Ashless dispersants are characterized by polar groups attached to relatively high molecular weight hydrocarbon chains. Typical ashless dispersants include N-substituted long-chain alkenyl succinimides with a variety of chemical structures, including those conforming to formula (XI):

[0111]

[0112] In one aspect, each R 35 Independently, it is an alkyl group, and on the other hand, it is based on the molecular weight (M) of the polyisobutylene precursor. n ) is a polyisobutylene group with a concentration of 500-5000, and R 36The amine moiety is an alkylene group, typically an ethylene (C₂H₄) group. These molecules are usually derived from the reaction of an alkenyl acylating agent with a polyamine, and in addition to the simple imide structure shown above, there may be various bonds between the two moieties, including various amides and quaternary ammonium salts. In the above structure, the amine moiety is shown as an alkylene polyamine, but other aliphatic and aromatic monoamines and polyamines can also be used. Additionally, R... 35 The groups in the imide structure can have various bond patterns, including various cyclic bonds. The ratio of the carbonyl group of the acylinter to the nitrogen atom of the amine can be from 1:0.5 to 1:3, and in other cases from 1:1 to 1:2.75 or from 1:1.5 to 1:2.5. Succinimide dispersants are described more fully in U.S. Patents 4,234,435 and 3,172,892 and EP 0355895.

[0113] Another type of ashless dispersant is high molecular weight esters. These substances are similar to the succinimides mentioned above, except that they can be prepared by reacting a hydrocarbon acylating agent with an aliphatic polyol (such as glycerol, pentaerythritol, or sorbitol). U.S. Patent 3,381,022 describes this substance in more detail.

[0114] Another class of ashless dispersants are Mannich bases. These are substances formed by the condensation of higher molecular weight alkyl-substituted phenols, alkylene polyamines, and aldehydes (such as formaldehyde). Such substances may have the general formula (XII):

[0115]

[0116] Where R 38 It is an alkylene group, such as an ethylene group (-CH2CH2-); and R 39 It is a hydrocarbon substituent having about 40 to about 20,000 carbon atoms, or about 80 to about 250 carbon atoms. In one aspect, R 39 The substituents are selected from polyisobutyl and polypropylene, derived from the partial alkylation of phenol using polybutene or polypropylene. The aforementioned Mannich base dispersant is described in more detail in U.S. Patent 3,634,515.

[0117] Other dispersants include polymer dispersing additives, which are typically hydrocarbon-based polymers containing polar functionality to impart dispersing properties to the polymer.

[0118] The dispersant can also be post-treated by reacting with any of a variety of reagents. These reagents include urea, thiourea, dimercaptothiadiazole, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, nitriles, epoxides, boron compounds, and phosphorus compounds. U.S. Patent 4,654,403 discloses a reference detailing such treatments.

[0119] Based on the total weight of the composition, the amount of dispersant in the fully formulated lubricant of the present invention may be at least 0.1%, or at least 0.3% by weight, or 0.5% by weight, or 1% by weight of the lubricant composition, and in some respects, at most 9% by weight, or 8% by weight, or 6% by weight, or 4% by weight, or 3% by weight, or 2% by weight.

[0120] Viscosity modifier

[0121] Another performance additive component that can be used in lubricants disclosed in this invention is a viscosity modifier. Viscosity modifiers (VMs) and dispersant viscosity modifiers (DVMs) are well known. Examples of VMs and DVMs may include polymethacrylates, polyacrylates, polyolefins, hydrogenated vinyl aromatic-diene copolymers (e.g., styrene-butadiene, styrene-isoprene), styrene-maleate copolymers, and similar polymers, including homopolymers, copolymers, and graft copolymers. DVMs may include nitrogen-containing methacrylate polymers, such as nitrogen-containing methacrylate polymers derived from methyl methacrylate and dimethylaminopropylamine.

[0122] Examples of commercially available VMs, DVMs, and their chemical types may include the following: polyisobutylene (such as Indopol from BPAmoco). TM Or obtained from ExxonMobil's Parapol TM ); olefin copolymers (such as Lubrizol derived from Lubrizol) TM 7060, 7065, and 7067, as well as Lucant from Mitsui. TM HC-2000L and HC-600); hydrogenated styrene-diene copolymers (such as Shellvis from Shell). TM 40 and 50, and those from Lubrizol 7308 and 7318); styrene / maleic acid ester copolymers, which are dispersant copolymers (such as those obtained from Lubrizol). 3702 and 3715); polymethacrylates, some of which have dispersant properties (such as Viscoplex from RohMax). TM Series, Hitec from Afton TM A series of viscosity index improvers and derived from Lubrizol 7702 7727、 7725 and 7720C); olefin-grafted-polymethacrylate polymers (such as Viscoplex from RohMax) TM2-500 and 2-600); and hydrogenated polyisoprene star polymers (such as Shellvis from Shell). TM Viscosity modifiers that can be used are described in U.S. Patents 5,157,088, 5,256,752, and 5,395,539. VM and / or DVM can be used in functional fluids at concentrations of up to 20% by weight. Concentrations of 1% to 12% by weight or 3% to 10% by weight can be used based on the weight of the total lubricant composition.

[0123] antioxidants

[0124] Another performance additive component that can be used in lubricants disclosed in this invention is an antioxidant. Antioxidants include phenolic antioxidants, which can be hindered phenolic antioxidants, with one or two ortho positions on the phenolic ring occupied by a bulky group (such as a tert-butyl group). The para position may also be occupied by a hydrocarbon group or a group bridging two aromatic rings. In some aspects, the para position is occupied by an ester-containing group (such as an antioxidant of, for example, formula (XIII)).

[0125]

[0126] Where R 40 The group is a hydrocarbon group, such as an alkyl group containing, for example, 1 to 18, 2 to 12, 2 to 8, or 2 to 6 carbon atoms; and the tertiary alkyl group may be a tert-butyl moiety. Such antioxidants are described in more detail in U.S. Patent 6,559,105.

[0127] Antioxidants also include aromatic amines. In one aspect, aromatic amine antioxidants may comprise alkylated diphenylamines (such as nonylated diphenylamine or a mixture of dinonylated diphenylamine and monononylated diphenylamine), or alkylated phenylnaphthylamines, or mixtures thereof.

[0128] Antioxidants also include sulfurized olefins, such as monosulfides or disulfides, or mixtures thereof. These substances typically have sulfur bonds containing 1 to 10 sulfur atoms, for example, 1 to 4, 1, or 2 sulfur atoms. Substances that can be sulfurized to form sulfurized organic compositions of the present technology include oils, fatty acids and esters, olefins and polyolefins, terpenes, or Diels-Alder adducts derived therefrom. Details of methods for preparing some of these sulfurized substances can be found in U.S. Patents 3,471,404 and 4,191,659.

[0129] Molybdenum compounds can also be used as antioxidants, and such substances can be used for a variety of other functions, such as anti-wear agents or friction modifiers. U.S. Patent 4,285,822 discloses a lubricating oil composition containing a molybdenum- and sulfur-containing composition, which is prepared by combining a polar solvent, an acidic molybdenum compound, and an oil-soluble basic nitrogen compound to form a molybdenum-containing complex and contacting the complex with carbon disulfide to form the molybdenum- and sulfur-containing composition.

[0130] Other substances that can be used as antioxidants include titanium compounds. U.S. Patent 7,727,943 discloses a variety of titanium compounds, including titanium alkoxides and titanium acid dispersants, which can also impart improved deposit control and filtration capabilities. Other titanium compounds include titanium carboxylate, such as titanium neodecanoate.

[0131] Typical amounts of antioxidants will, of course, depend on the specific antioxidant and its effectiveness, but based on the weight of the total composition, illustrative total amounts may range from about 0.01% by weight to about 5% by weight, or from about 0.15% by weight to about 4.5% by weight, or from about 0.2% by weight to about 4% by weight.

[0132] anti-wear agent

[0133] The lubricant compositions disclosed in this invention may further comprise anti-wear agents. In one aspect, the anti-wear agent is a metal phosphate salt of formula (XIV):

[0134] [(R 43 O)(R 44 O)P(=S)(-S)] n -M(XIV)

[0135] Where R 43 and R 44 It is independently a hydrocarbon group containing 3 to 30 carbon atoms, and can be obtained by heating phosphorus pentasulfide (P2S5) with an alcohol or phenol to form O,O-dialkyl dithiophosphate. The reaction provides R. 43 and R 44 The alcohol in the group can be a mixture of alcohols, such as a mixture of isopropanol and 4-methyl-2-pentanol, and in some cases, a mixture of secondary and primary alcohols (such as isopropanol and 2-ethylhexanol). The resulting acid can react with an alkaline metal compound to form a salt. The metal M with a valence state of n is typically aluminum, lead, tin, manganese, cobalt, nickel, zinc, or copper, and in many cases zinc, to form zinc dialkyldithiophosphate (ZDP). Such substances are well known and readily available to those skilled in the art of lubricant formulations. For example, U.S. Patent 7,772,171 discloses a suitable variation that provides good phosphorus retention in engines.

[0136] Examples of substances that can be used as anti-wear agents include phosphorus-containing anti-wear agents / extreme pressure agents, such as metal thiophosphates, phosphate esters and their salts, phosphorus-containing carboxylic acids, esters, ethers and amides as described above; and phosphites. In some aspects, phosphorus anti-wear agents may be present in amounts of about 0.01% to about 0.2%, or about 0.015% to about 0.15%, or about 0.02% to about 0.1%, or about 0.025% to about 0.08% phosphorus. Typically, the anti-wear agent is zinc dialkyl dithiophosphate (ZDP). For a typical ZDP that may contain 11% P (on an oil-free basis), suitable amounts may include about 0.09% to about 0.82%. Phosphorus-free anti-wear agents include borate esters (including borate epoxides), dithiocarbamate compounds, molybdenum-containing compounds, and sulfurized olefins.

[0137] Other substances that can be used as anti-wear agents include tartaric esters, tartaramides, and tartaric imides. Examples include oleyl tartaric imides (imides formed from oleylamine and tartaric acid) and oleyl diesters (from, for example, a mixture of C... 12 -C 16 Alcohols). Other related substances that may be used typically include esters, amides, and imides of other hydroxycarboxylic acids, including hydroxypolycarboxylic acids, such as tartaric acid, citric acid, lactic acid, glycolic acid, hydroxypropionic acid, hydroxyglutaric acid, and mixtures thereof. These materials can also impart additional properties to the lubricant beyond anti-wear properties. These substances are described in more detail in U.S. Patent No. 7,651,987 and PCT Publication WO WO2010 / 077630. Based on the total weight of the composition, such derivatives of hydroxycarboxylic acids (or compounds derived from hydroxycarboxylic acids) may typically be present in the lubricating composition in amounts from about 0.1% by weight to about 5% by weight, or from about 0.2% by weight to about 3% by weight, if present.

[0138] Unless otherwise stated, the amounts of each chemical component described herein do not include any solvents or diluents that are commonly found in commercial substances, i.e., on an active chemical basis. However, unless otherwise stated, each chemical or composition mentioned herein should be interpreted as a commercial-grade substance that may contain isomers, byproducts, derivatives, and other such substances generally understood to be present in commercial-grade products.

[0139] Based on the weight of the total composition, these additional performance additives may be present in the bulk lubricant composition in amounts of about 0% by weight or about 0.1% by weight to about 30% by weight, or about 1% by weight to about 20% by weight, or about 3% by weight to about 20% by weight, or about 5% by weight to about 18% by weight, or about 8% by weight to about 15% by weight, or about 10% by weight to about 12% by weight. In some aspects, an oil having a lubricating viscosity will constitute the balance of the composition, and / or based on the weight of the total composition, may be present in amounts of about 66% by weight to about 99.9% by weight, or about 99.8% by weight, or about 78% by weight to about 98.9% by weight, or about 78.5% by weight to about 94.5% by weight, or about 78.9% by weight to about 89.1% by weight, or about 83.9% by weight to about 89.1% by weight, or about 85% by weight.

[0140] In different respects, the lubricating composition may have the composition described in the table below.

[0141]

[0142] The lubricating compositions disclosed in this invention can be used in internal combustion engines. Engine components may have steel or aluminum surfaces (typically steel surfaces) and may also be coated with, for example, diamond-like carbon (DLC) coatings.

[0143] The aluminum surface can be made of an aluminum alloy, which can be a eutectic or hypereutectic aluminum alloy (such as those derived from aluminum silicate, alumina, or other ceramic materials). The aluminum surface can be present on cylinder bores, cylinder blocks, or piston rings having an aluminum alloy or aluminum composite.

[0144] The internal combustion engine may be equipped with an emission control system or a turbocharger. Examples of emission control systems include a diesel particulate filter (DPF) or a system employing selective catalytic reduction (SCR). The internal combustion engine may or may not have an exhaust gas recirculation system.

[0145] In one respect, an internal combustion engine can be a diesel-fueled engine (typically a heavy-duty diesel engine), a gasoline-fueled engine, a natural gas-fueled engine, or an engine fueled by a mixture of gasoline and alcohol. The engine can be a spark-ignition engine and / or a compression-ignition engine. The internal combustion engine can be a 2-stroke or 4-stroke engine. Suitable internal combustion engines include marine diesel engines, aviation piston engines, low-load diesel engines, and gasoline-fueled automobile and truck engines.

[0146] The internal combustion engine described in this article differs from a gas turbine. In an internal combustion engine, individual combustion activities convert linear reciprocating forces into rotational torque via rods and a crankshaft. Conversely, in a gas turbine (which may also be called a jet engine), the continuous combustion process continuously generates rotational torque without translation, and thrust can also be generated at the exhaust outlet. These differences in the operating conditions of gas turbines and internal combustion engines result in different operating environments and stresses.

[0147] Regardless of the sulfur, phosphorus, or sulfated ash (ASTM D-874) content, the lubricant composition for internal combustion engines is suitable for any engine lubricant. In one aspect, based on the total weight of the engine oil composition, the sulfur content of the engine oil having a lubricating viscosity may be 1% by weight or less, or 0.8% by weight or less, or 0.5% by weight or less, or 0.3% by weight or less. In another aspect, based on the total weight of the engine oil composition, the sulfur content may range from 0.001% by weight to 0.5% by weight, or from 0.01% by weight to 0.3% by weight. In another aspect, based on the total weight of the engine oil composition, the phosphorus content may be 0% by weight, or 0.2% by weight or less, or 0.12% by weight or less, or 0.1% by weight or less, or 0.1% by weight or less, or 0.085% by weight or less, or 0.08% by weight or less, or 0.06% by weight or less, or 0.055% by weight or less, or 0.05% by weight or less. In one aspect, the phosphorus content, based on the total weight of the engine oil composition, is 0 ppm, or may be in the range of 100 ppm to 1000 ppm, or 200 ppm to 600 ppm. In another aspect, the total sulfated ash content, based on the total weight of the engine oil composition, may be 2% by weight or less, or 1.5% by weight or less, or 1.1% by weight or less, or 1% by weight or less, or 0.8% by weight or less, or 0.5% by weight or less, or 0.4% by weight or less. In another aspect, the sulfated ash content, based on the total weight of the engine oil composition, may be 0.05% by weight to 0.9% by weight, or 0.1% by weight to 0.2% by weight, or up to 0.45% by weight.

[0148] In one aspect, the lubricating composition is characterized by having at least one of the following: (i) a sulfur content of about 0.5% by weight or less, or 0.4% by weight or less; (ii) a phosphorus content of about 0.1% by weight or less; and (iii) a sulfated ash content of about 1.5% by weight or less, or a combination thereof. In another aspect, the lubricating composition comprises less than about 1.5% by weight, or less than about 1.25% by weight, or less than about 1.0% by weight of unreacted polyisobutylene.

[0149] In some respects, the lubricant composition is an engine oil composition for turbocharged direct injection (TDI) engines.

[0150] The technology disclosed in this invention also provides a method for reducing deposits and mitigating seal degradation in an internal combustion engine, the method comprising:

[0151] (1) Providing an engine with a lubricant composition, the lubricant composition comprising:

[0152] a) Oils with lubricating viscosity; and

[0153] b) Basic ashless additives selected from secondary amines of the following formula:

[0154]

[0155] R1 to R6 are selected from hydrogen, C6-C 14 Aromatic groups, C1-C 24 Hydrocarbon group, or C2 to C 16 Hydrocarbon group, or C3 to C 12 The hydrocarbon group, or C4 to C8 hydrocarbon groups and combinations thereof, wherein at least two of R1 to R6 represent aromatic groups, and no more than two of R1 to R3 and R4 to R6 can be aromatic at the same time, and the total number of aromatic groups represented by R1 to R6 cannot exceed three, and no two of R1 to R3 can be hydrogen at the same time unless one of R1 to R3 is an aromatic group, or no two of R4 to R6 can be hydrogen at the same time unless one of R4 to R6 is an aromatic group; and (2) operating the engine. In some respects, the engine is a turbocharged direct injection (TDI) engine.

[0156] The following examples provide an illustration of the technology disclosed in this invention. Unless otherwise specified, the amounts of components listed in the following examples are given as a weight percentage based on the total weight of the composition. These examples are non-exhaustive and are not intended to limit the scope of the technology.

[0157] Example

[0158] Example A

[0159] Tetrahydrofuran (1500 ml) and diphenylmethylamine (172.8 g) were added to a 3 L flask equipped with a stirrer, thermocouple, nitrogen inlet, and water-cooled condenser. 2-Butanone (68 g) was added, and the mixture was stirred at ambient room temperature for approximately 1 hour. STAB (sodium triacetoxyborohydride) (250 g) was added to the mixture over approximately 1.5 hours, and the reaction mixture was stirred at ambient room temperature for approximately 4 days. At this point, the reaction mixture was quenched with 2M NaOH (aqueous solution) (551 ml) over 1.5 hours to control the exothermic reaction. Tert-butyl methyl ether (1268 ml) was added to the reaction mixture, and the organic layer was separated. The organic matter was dried, filtered, and the product was separated by vacuum stripping. The product was purified by adding 2M NaOH (aqueous solution) to a beaker with stirring for 1 hour. At this point, the mixture was extracted with dichloromethane (500 ml). The organic matter was separated, washed with water (500 ml), dried with MgSO4, and filtered. The solution was then stripped under reduced pressure to obtain N-diphenylmethylbut-2-amine (176.2 g) represented by the following structure:

[0160]

[0161] Example B

[0162] According to the procedure in Example A, benzaldehyde is amination with α-methylbenzylamine to obtain N-benzyl-1-phenylethyl-1-amine represented by the following structure:

[0163]

[0164] Example C (Comparison)

[0165] According to the procedure in Example A, 2-ethylhexanal is amination with α-methylbenzylamine to obtain 2-ethyl-N-(1-(4-methoxyphenyl)ethyl)hex-1-amine represented by the following structure:

[0166]

[0167] Example D (Comparison)

[0168] According to the procedure in Example A, 2-ethylhexanal is amination with 1-cyclohexylethylamine to obtain N-(1-cyclohexylethyl)-2-ethylhex-1-amine represented by the following structure:

[0169]

[0170] Example E

[0171] Xylene (2000 ml) was added to a 5 L flask equipped with a stirrer, PTFE thermocouple, nitrogen inlet, and water-cooled condenser, followed by diphenylmethylamine (238.9 g). Sodium carbonate (207.3 g) was then added, followed by 1-bromoethylbenzene (241.3 g). The reaction mixture was stirred and heated to 140 °C for 20 hours. The reaction mixture was then cooled and filtered. The filtrate was stripped under reduced pressure, leaving an orange oil (130.6 g). The product was further purified by silica gel column chromatography, eluting with 10% ethyl acetate / hexane. After solvent removal, N-diphenylmethyl-1-phenylethyl-1-amine (170.4 g), a pale yellow liquid, was obtained with the following structure:

[0172]

[0173] Example F

[0174] According to the procedure in Example E, α-methylbenzylamine is alkylated with 1-bromoethylbenzene to obtain bis(1-phenylethyl)amine having the following structure:

[0175]

[0176] Example G

[0177] According to the procedure in Example E, 1-(4-methoxy-phenyl)ethylamine is alkylated with 1-bromoethylbenzene to obtain 1-(4-methoxyphenyl)-N-(1-phenylethyl)ethyl-1-amine having the following structure:

[0178]

[0179] Example H (Comparison)

[0180] According to the procedure in Example E, 2-ethylhexylamine is alkylated with 1-bromoethylbenzene to obtain 2-ethyl-N-(1-phenylethyl)hex-1-amine having the following structure:

[0181]

[0182] Example 1 (Comparative)

[0183] According to the procedure in Example E, cyclohexylamine is alkylated with 1-bromoethylbenzene to obtain 1-cyclohexyl-N-(1-phenylethyl)ethyl-1-amine having the following structure:

[0184]

[0185] Lubricating composition and test data .

[0186] A series of 15W-40 engine lubricants with lubricating viscosity based on Group II base oils were prepared. These lubricants contained the aforementioned basic amine additives as well as conventional additives, including isobutylene succinimide dispersants, polymer viscosity modifiers, highly basic detergents, antioxidants (a combination of phenolic esters and diarylamines), zinc dialkyl dithiophosphate (ZDDP), and other conventional performance additives as listed below (Table 1). The calcium, magnesium, phosphorus, zinc, and ash contents of each embodiment are also partially presented in the table to show that each embodiment has similar amounts of these substances, and thus provide a suitable comparison between comparative examples and exemplary embodiments of the present technology.

[0187] Table 1 (Lubricating Compositions)

[0188]

[0189]

[0190] 1 Unless otherwise specified, all processing rates are oil-free.

[0191] 2 A combination of conventional (chlorination method) and thermal "ene" polyisobutylene succinimide dispersants was prepared using a mixture of aliphatic and aromatic polyamines.

[0192] 3 Boron-containing polyisobutylene succinimide dispersant.

[0193] 4 A combination of highly alkaline alkylbenzene sulfonate calcium detergent (TBN of 170 and 500 mg KOH / g).

[0194] 5 Highly alkaline calcium thiocoupling phenol detergent (TBN 400mg KOH / g).

[0195] 6 Combinations of sulfurized olefins, alkylated diarylamine compounds, and hindered phenolic ester compounds.

[0196] 7 Ethylene-propylene copolymers functionalized with a mixture of aromatic amines and aromatic polyamines.

[0197] 8 Other additives include pour point depressants, corrosion inhibitors, and defoamers.

[0198] The engine lubricant compositions formulated in Table 1 were evaluated in bench and engine tests designed to assess the lubricant's ability to prevent corrosion and mitigate seal degradation. Further testing of the lubricant compositions was conducted to evaluate their ability to prevent or reduce deposit formation, provide cleanliness, improve oxidation stability, and reduce or prevent acid-mediated wear or lubricant degradation. Industry-standard deposition and oxidation tests were performed on lubricant samples, such as Komatsu heat pipe (KHT), differential pressure scanning calorimetry (PDSC) (e.g., L85-99), MHT TEOST (ASTM D7097), and TEOST 33C (ASTM D6335). Industry-standard seal and corrosion bench tests were performed on the lubricant compositions.

[0199] Lubricant samples were subjected to a 168-hour, 150°C compatibility test with fluorocarbon seals. Seal material (“MB” - Mercedes Benz seal) DBL6674-FKM was evaluated before and after immersion in the lubricant under standard conditions. Corrosion testing of the lubricant was also performed according to ASTM D6594. The compositions and results are summarized in Table 2 below.

[0200] Table 2 (Evaluation of Corrosion and Seals)

[0201]

[0202] 1 Copper strip corrosion test (ASTM D130).

[0203] 2 ASTM D130 visual grade: Grade 1, Name - Slightly darkened, Description - Light orange, almost identical to a freshly polished strip (1a).

[0204] Data show that lubricant compositions containing amine additives of the present invention provide TBN titrated by both strong (D4739) and weak (D2896) substances while maintaining strong corrosion resistance.

[0205] Each of the foregoing references is incorporated herein by reference, including any prior application claiming priority thereto, whether or not specifically listed above. Reference to any reference is not an admission that the reference conforms to the prior art or constitutes general knowledge of a person skilled in the art in any jurisdiction. Unless expressly stated in the examples or otherwise, all numerical quantities of matter, reaction conditions, molecular weight, number of carbon atoms, etc., specified in this specification should be understood to be modified by the word “about.” It should be understood that the upper and lower limits of the quantities, ranges, and proportions described herein can be combined independently. Similarly, the range and quantity of each element of the technology disclosed in this invention can be used in conjunction with the range or quantity of any other element. As used herein, the expression “consisting substantially of…” allows for the inclusion of substances that do not materially affect the basic and novel properties of the composition under consideration.

Claims

1. A lubricant composition comprising: a) Oils with lubricating viscosity; and b) A secondary amine having a first α-carbon and a second α-carbon bonded to the amine nitrogen, wherein the first α-carbon contains two aromatic substituents and the second α-carbon contains one aromatic substituent and one alkyl substituent, wherein the alkyl substituent is selected from C1 to C2. 24 Alkyl group, or wherein the first α-carbon contains two aromatic substituents and the second α-carbon contains two alkyl substituents and no aromatic substituents, wherein the alkyl substituents are selected from C1 to C2. 24 Alkyl group, or wherein the first α-carbon contains an aromatic substituent and a hydrocarbon substituent and the second α-carbon contains an aromatic substituent and no hydrocarbon substituent, wherein the hydrocarbon substituent is selected from C1 to C2. 24 Alkyl group, or wherein the first α-carbon contains an aromatic substituent and a alkyl substituent and the second α-carbon contains an aromatic substituent and a alkyl substituent, wherein the alkyl substituent is selected from C1 to C2. 24 Alkyl group, and wherein at least one of the aromatic substituents is substituted with a substituent selected from the following: C1-C 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations.

2. The lubricant composition according to claim 1, wherein the aromatic substituent is selected from phenyl, naphthyl, anthraceneyl, phenanthrene, and combinations thereof.

3. The lubricant composition according to claim 1, wherein the aromatic substituents are independently C1-C2. 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations of substitutions.

4. The lubricant composition according to claim 2, wherein the aromatic substituents are independently C1-C2. 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations of substitutions.

5. The lubricant composition according to any one of claims 1-4, wherein the hydrocarbon substituent is selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and combinations thereof.

6. The lubricant composition according to any one of claims 1-4, wherein the aromatic substituent is a substituted and unsubstituted phenyl group, and the hydrocarbon substituent is a methyl group.

7. The lubricant composition according to claim 1, wherein component b) is selected from compounds of the following formula: Where R1 and R2 are aromatic substituents, R3 is hydrogen, R4 is an aromatic substituent, and R5 is hydrogen. R6 is C1-C 24 Alkyl groups, or wherein R1 and R2 are aromatic substituents, R3 is hydrogen, and R4 and R5 is independently selected from C1-C 24 Alkyl group, and R6 is hydrogen, or wherein R1 is an aromatic substituent, R2 is hydrogen, and R3 is selected from C1-C6. 24 Alkyl group, R4 is an aromatic substituent, and R5 and R6 are hydrogen.

8. The lubricant composition according to claim 7, wherein the aromatic substituent is selected from phenyl, naphthyl, anthraceneyl, phenanthrene, and combinations thereof.

9. The lubricant composition according to claim 7, wherein the aromatic substituents are independently C1-C2. 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations of substitutions.

10. The lubricant composition according to claim 8, wherein the aromatic substituents are independently C1-C2. 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations of substitutions.

11. The lubricant composition according to claim 7, wherein component b) is selected from compounds of the following formula: R6 is selected from hydrogen and methyl, and R is independently selected from hydrogen, C1-C. 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkyl groups and their combinations.

12. The lubricant composition according to claim 7, wherein component b) is selected from compounds of the following formula: R4 and R5 are independently selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and octyl, and R is independently selected from hydrogen, C1-C2, C2 ... 10 Alkyl, C2-C 10 alkenyl, amino, hydroxyl, and hydroxy-substituted C1-C 10 Alkyl, C1-C 10 Alkoxy groups and their combinations.

13. The lubricant composition according to any one of claims 1-4, wherein component b) is selected from N-diphenylmethyl-1-phenyl-1-amine, N-diphenylmethylbut-2-amine, N-benzyl-1-phenylethyl-1-amine, 1-(4-methoxyphenyl)-N-phenylethyl)ethyl-1-amine, and mixtures thereof.

14. The lubricant composition according to any one of claims 1-4, wherein the oil having a lubricating viscosity comprises mineral oil, synthetic oil, or a combination thereof.

15. The lubricant composition according to any one of claims 1-4, wherein the oil having a lubricating viscosity is at least one of API Group I oil, Group II oil, Group III oil, and mixtures thereof.

16. The lubricant composition according to any one of claims 1-4, wherein the secondary amine is capable of acid titration according to ASTM D4739.

17. The lubricant composition according to any one of claims 1-4, wherein the secondary amine is titrated to a value greater than 100 mg KOH / g according to ASTM D4739.

18. The lubricant composition according to any one of claims 1-4, wherein the secondary amine is present in an amount ranging from 0.1% to 6% by weight based on the total weight of the composition.

19. The lubricant composition according to any one of claims 1-4, wherein the secondary amine is present in an amount ranging from 0.2% to 4% by weight based on the total weight of the composition.

20. The lubricant composition according to any one of claims 1-4, wherein the secondary amine is present in an amount ranging from 0.25% by weight to 2% by weight based on the total weight of the composition.

21. The lubricant composition according to any one of claims 1-4, wherein the secondary amine is present in an amount ranging from 0.3% to 1% by weight based on the total weight of the composition.

22. The lubricant composition according to any one of claims 1-4, wherein the secondary amine delivers ashless TBN at a concentration of 0.5 mg KOH / g to 8 mg KOH / g as measured according to ASTM D4739.

23. The lubricant composition according to any one of claims 1-4, wherein the secondary amine delivers ashless TBN at a concentration of 0.7 mg KOH / g to 7 mg KOH / g as measured according to ASTM D4739.

24. The lubricant composition according to any one of claims 1-4, wherein the secondary amine delivers ashless TBN at a concentration of 0.7 mg KOH / g to 5 mg KOH / g as measured according to ASTM D4739.

25. The lubricant composition according to any one of claims 1-4, wherein the secondary amine delivers ashless TBN at a concentration of 0.8 mg KOH / g to 4 mg KOH / g as measured according to ASTM D4739.

26. The lubricant composition according to any one of claims 1-4, wherein the secondary amine delivers ashless TBN at a concentration of 0.8 mg KOH / g to 2.5 mg KOH / g as measured according to ASTM D4739.

27. The lubricant composition according to any one of claims 1-4, wherein the secondary amine delivers ashless TBN at a concentration of 0.8 mg KOH / g to 1.5 mg KOH / g as measured according to ASTM D4739.

28. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 1% by weight or less sulfur.

29. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.8% by weight or less sulfur.

30. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.5% by weight or less sulfur.

31. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.3% by weight or less sulfur.

32. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0% by weight of phosphorus.

33. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.2% by weight or less phosphorus.

34. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.12% by weight or less phosphorus.

35. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.1% by weight or less phosphorus.

36. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.085% by weight or less phosphorus.

37. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.08% by weight or less phosphorus.

38. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.06% by weight or less phosphorus.

39. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.055% by weight or less phosphorus.

40. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.05% by weight or less phosphorus.

41. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.4% by weight or less sulfated ash.

42. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.5% by weight or less sulfated ash.

43. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 0.8% by weight or less sulfated ash.

44. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 1% by weight or less sulfated ash.

45. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 1.2% by weight or less sulfated ash.

46. ​​The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 1.1% by weight or less sulfated ash.

47. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition contains 1.5% by weight or less sulfated ash.

48. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition further comprises an additive selected from one or more ashless dispersants, viscosity modifiers, pour point depressants, antioxidants, friction modifiers, detergents, anti-wear agents, corrosion inhibitors, defoamers, or any combination thereof.

49. The lubricant composition according to any one of claims 1-4, wherein the lubricant composition further comprises an additive selected from: one or more ashless dispersants, viscosity modifiers, pour point depressants, antioxidants, friction modifiers, zinc dithiophosphate, detergents, corrosion inhibitors, defoamers, or any combination thereof.

50. The lubricant composition of claim 48, wherein the lubricant composition further comprises a detergent selected from one or more highly alkaline metal detergents.

51. The lubricant composition of claim 50, wherein the one or more highly alkaline detergents are present in an amount sufficient to deliver 0.05% to 1.2% by weight of sulfated ash to the lubricant composition.

52. The lubricant composition of claim 50, wherein the one or more highly alkaline detergents are present in an amount sufficient to deliver 0.25% to 0.85% by weight of sulfated ash to the lubricant composition.

53. The lubricant composition of claim 50, wherein the one or more highly alkaline detergents are present in an amount sufficient to deliver 0.15% to 0.5% by weight of sulfated ash to the lubricant composition.

54. The lubricant composition of claim 50, wherein the one or more highly alkaline detergents are present in an amount sufficient to deliver less than 1% by weight of sulfated ash to the lubricant composition.

55. The lubricant composition of claim 50, wherein the one or more highly alkaline detergents are present in an amount sufficient to deliver less than 0.75% by weight of sulfated ash to the lubricant composition.

56. The lubricant composition of claim 50, wherein the one or more highly alkaline detergents are present in an amount sufficient to deliver less than 0.45% by weight of sulfated ash to the lubricant composition.

57. A method for mitigating the deterioration of crankcase seals in an internal combustion engine, the method comprising providing the internal combustion engine with a lubricant composition according to any one of claims 1 to 56.

58. A method of lubricating an internal combustion engine, the method comprising providing the internal combustion engine with a composition according to any one of claims 1 to 27 and operating the internal combustion engine under normal operating conditions.

59. A method for neutralizing acidic combustion byproducts in an internal combustion engine, the method comprising providing the internal combustion engine with a composition according to any one of claims 1 to 15 and operating the internal combustion engine under normal operating conditions.

60. A method for mitigating rust formation in an internal combustion engine, the method comprising providing the internal combustion engine with a composition according to any one of claims 1 to 56 and operating the internal combustion engine under normal operating conditions.

61. Use of the lubricant composition according to any one of claims 1 to 56 for reducing rust formation in an internal combustion engine.

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