Lubricating composition and method of lubricating an internal combustion engine

Abstract

The disclosed technology provides lubricating compositions and methods of lubricating internal combustion engines, wherein the lubricating composition comprises an oil of lubricating viscosity, one or more metal-containing, sulfur-free, alkylphenol-based detergents, an alkaline earth metal sulfonate detergent, a polyisobutenyl succinimide dispersant, and a dispersant viscosity modifier having a number average molecular weight of at least 20,000. The inventive lubricating compositions can be formulated to have a lower HTHS viscosity and reduced phosphorus content while providing protection against adhesive wear.

Description

Invention Field

[0001] The disclosed technology relates to lubricants, particularly for internal combustion engines, including diesel engines. In particular, the disclosed technology relates to lubricating compositions with lower viscosity, which provide improved protection against adhesive wear. Background Technology

[0002] Adhesive wear, also known as stick-tear wear, is a common wear problem in internal combustion engines. It occurs when material from two mating metal parts is unevenly transferred from one part to the other because the lubricant cannot keep the parts separated or maintain a sufficiently low temperature in the system. In these cases, micro-welds develop between the mating parts, which then tear apart as the parts move away from each other. Adhesive wear is typically addressed by increasing the viscosity of the lubricant and / or by increasing the amount of anti-wear additives in the lubricant composition.

[0003] Some lubricating compositions, such as crankcase lubricants, are formulated to have a lower high-temperature high-shear (HTHS) viscosity to improve fuel economy. Additionally, for environmental reasons, some lubricating compositions are formulated with lower levels of anti-wear additives, particularly phosphorus- or sulfur-containing anti-wear additives. However, a reduction in HTHS viscosity and / or anti-wear additives generally leads to increased metal-to-metal adhesive wear.

[0004] Therefore, a lubricant with a low HTHS viscosity is needed that still provides protection against adhesive wear. Furthermore, lubricating compositions containing low levels of phosphorus or sulfur are required to maintain adequate adhesive wear resistance. Summary of the Invention

[0005] In one embodiment, the present invention relates to a lubricating composition comprising an oil having a lubricating viscosity, one or more metal-containing sulfur-free detergents derived from alkylphenols in an amount of at least 0.2 wt% of an alkylphenol-containing soap, one or more alkaline earth metal sulfonate detergents in an amount of at least 0.8 wt% of a sulfonate soap, 1 wt% to 4.5 wt% of one or more polyisobutylene succinimide dispersants, and 0.1 wt% to 1.2 wt% of a dispersant viscosity improver derived from a polyolefin with a number average molecular weight of at least 20,000, wherein the lubricating composition contains less than 0.2 wt% of a sulfur-coupled phenolic salt detergent.

[0006] In another embodiment, the present invention relates to a method of lubricating a compression ignition internal combustion engine, comprising supplying a low-phosphorus lubricant composition to the engine, the low-phosphorus lubricant composition comprising an oil having a lubricating viscosity, one or more metal-containing sulfur-free detergents derived from alkylphenols in an amount of at least 0.2 wt% of an alkylphenol-containing soap, one or more alkaline earth metal sulfonate detergents in an amount of at least 0.8 wt% of a sulfonate soap, 1 wt% to 4.5 wt% of one or more polyisobutylene succinimide dispersants, and 0.1 wt% to 1.2 wt% of a dispersant viscosity improver derived from a polyolefin with a number average molecular weight of at least 20,000, wherein the lubricant composition contains less than 0.2 wt% of a sulfur-coupled phenol salt detergent.

[0007] In another embodiment, the present invention relates to a method for reducing adhesive wear in a compression engine lubricated with a low-phosphorus lubricant composition, comprising supplying a lubricant composition to the engine comprising an oil having a lubricating viscosity, one or more metal-containing sulfur-free detergents derived from alkylphenols in an amount of at least 0.2 wt% of an alkylphenol-containing soap, one or more alkaline earth metal sulfonate detergents in an amount of at least 0.8 wt% of a sulfonate soap, 1 wt% to 4.5 wt% of one or more polyisobutylene succinimide dispersants, and 0.1 wt% to 1.2 wt% of a dispersant viscosity improver derived from a polyolefin with a number average molecular weight of at least 20,000, wherein the lubricant composition contains less than 0.2 wt% of a thiocoupled phenol salt detergent. Invention Details

[0009] The disclosed technology provides lubricating compositions and methods for lubricating internal combustion engines. The lubricating compositions of the present invention comprise an oil having a lubricating viscosity, one or more metal-containing sulfur-free detergents derived from alkylphenols in an amount of at least 0.2 wt% of an alkylphenol-containing soap, 1 wt% to 4.5 wt% of one or more polyisobutylene succinimide dispersants, one or more alkaline earth metal sulfonate detergents in an amount of at least 0.8 wt% of a sulfonate soap, and 0.1 wt% to 1.2 wt% of a dispersant viscosity improver derived from polyolefins with a number average molecular weight of at least 20,000, wherein the lubricating composition contains less than 0.2 wt% of a sulfur-coupled phenolic salt detergent. Information regarding the components and other details of the lubricating compositions of the present invention is described below.

[0010] Oil with lubricating viscosity

[0011] The lubricating composition comprises an oil having a lubricating viscosity. This oil includes natural and synthetic oils, oils derived from hydrocracking, hydrogenation, and hydrorefining, unrefined, refined, and refined oils, and mixtures thereof. Various types of oils having lubricating viscosities are described below and can be used in the lubricating compositions of the present invention.

[0012] Unrefined oils are oils obtained directly from natural or synthetic sources, typically without (or with minimal) further purification.

[0013] 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.

[0014] Refined oil, also known as recycled oil or post-processed oil, is obtained through methods similar to those used to obtain refined oil, and is often further processed using techniques to remove waste additives and oil decomposition products.

[0015] Natural oils used to prepare the lubricants of this invention include animal oils, vegetable oils (e.g., castor oil), mineral lubricants such as liquid petroleum and solvent-treated or acid-treated mineral lubricants of the alkanes, cycloalkanes or mixed alkanes-cycloalkanes type, and oils derived from coal or shale or mixtures thereof.

[0016] Synthetic lubricants are useful and include hydrocarbon oils such as polymers and copolymers of olefins (e.g., polybutene, polypropylene, propylene isobutylene copolymer); 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.

[0017] Other synthetic lubricants include polyol esters (such as...) 3970), diesters, phosphoric acid-containing liquid esters (e.g., diethyl tert-methyl phosphate, diethyl trioctyl phosphate, and diethyl decanephosphonic acid), or polymerized tetrahydrofurans. Synthetic oils can be prepared 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 method, as well as other gas-liquid oils.

[0018] Oils with lubricating viscosity can also be defined according to the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. The five base oil groups are as follows: Group I (sulfur content >0.03 wt%, and / or <90 wt% saturated content, viscosity index 80-120); Group II (sulfur content ≤0.03 wt%, ≥90 wt% saturated content, viscosity index 80-120); Group III (sulfur content ≤0.03 wt%, ≥90 wt% saturated content, viscosity index ≥120); Group IV (all polyalphaolefins (PAOs)); and Group V (all others not included in Groups I, II, III, or IV).

[0019] Oils with lubricating viscosity can also be API Group II+ base oils. This term refers to Group II base oils with a viscosity index greater than or equal to 110 and less than 120, as described in SAE publications “Design Practice: Passenger Car Automatic Transmissions”, 4th edition, AE-29, 2012, pp. 12-9 and US8,216,448, column 1, line 57.

[0020] Oils with lubricating viscosity can also be API Group III+ base oils, a term referring to Group III+ base oils with a viscosity index greater than or equal to 130. Group III+ is known in the art and described in the "Lube Report," published February 26, 2014, by Nancy DeMarco in an article entitled "SKSees Group III Shortfall." This article can be obtained from http: / / www.aselube.com / media / 11910 / sk_sees_group_iii_shortfall.pdf.

[0021] Oils with lubricating viscosity can be API Group IV oils or mixtures thereof, i.e., polyalphaolefins. Polyalphaolefins can be prepared by metallocene catalytic methods or non-metallocene methods.

[0022] Oils with lubricating viscosity may include API Group I, II, III, IV, or V oils or mixtures thereof.

[0023] The amount of oil with lubricating viscosity present is usually the balance remaining after subtracting the sum of the amounts of the above-mentioned additives and other performance additives from 100% by weight.

[0024] The lubricating composition may be in the form of a concentrate and / or a fully formulated lubricant. If the lubricating composition disclosed is in the form of a concentrate (which may be combined with additional oils to form a whole or part finished lubricant), the ratio of each component of the disclosed technology to an oil having a lubricating viscosity and / or to a diluent includes 1:99 to 99:1 by weight, or 80:20 to 10:90 by weight.

[0025] In one embodiment, the lubricating composition may be a non-aqueous composition.

[0026] Oils with lubricating viscosity can refer to a single base oil or a mixture of base oils. According to ASTM D445-14, the kinematic viscosity of the oils used in the lubricating compositions of this invention at 100°C can be from 2 cSt to 20 cSt (or mm²). 2 / s). At ambient temperatures (5-30°C), the lubricating composition can be a liquid, i.e., not a gel or semi-solid.

[0027] Cleaning agent

[0028] The lubricating composition of the present invention contains a sulfur-free detergent containing metals and a sulfonate detergent containing alkaline earth metals. In addition, the lubricating composition may contain a small amount of a thiocoupled phenolic salt detergent.

[0029] As used herein, the term "soap" refers to the surfactant portion of a detergent, excluding metal bases such as calcium carbonate. "Soap content," metal ratio, and TBN are known to those skilled in the art and are explained in the standard textbook "Chemistry and Technology of Lubricants," Third Edition, Edited by RMMortier and S.T. Orszulik, Copyright 2010, pages 219 to 220 under the subheading 7.2.5. The term "soap" may also refer to the detergent matrix. For example, in the sulfonate detergents described herein, the soap may be a neutral salt of alkylbenzene sulfonic acid.

[0030] Furthermore, as used herein, all total base numbers cited were determined by ASTM method D2896-11.

[0031] Detergents containing metals are commonly referred to as “over-basic metal detergents.” Over-basic metal detergents can be considered as containing an oil-soluble neutral metal salt component and a metal carbonate component. Over-basic materials, also known as over-basic or super-basic salts, are typically homogeneous Newtonian systems characterized by a metal content exceeding the amount present according to the stoichiometric neutralization of the metal and a specific acidic organic compound that reacts with the metal. Over-basic materials are prepared by reacting an acidic material (typically an inorganic acid or lower carboxylic acid, and in one embodiment, carbon dioxide) with a reaction medium containing an acidic organic compound, an inert organic solvent (e.g., mineral oil, naphtha, toluene, xylene) for said acidic organic material, a stoichiometric excess of a metal base, and a mixture of a promoter such as phenol or alcohol and optionally ammonia. The acidic organic material typically has a sufficient number of carbon atoms, for example as a hydrocarbon substituent, to provide a degree of solubility in oil. The amount of excess metal is typically expressed as a metal ratio. The term “metal ratio” is the ratio of the total equivalent of the metal to the equivalent of the acidic organic compound. The metal ratio of a neutral metal salt is 1. A salt having 4.5 times the amount of metal present in a common salt will have a metal excess of 3.5 equivalents, or a ratio of 4.5.

[0032] Overly alkaline detergents are typically characterized by their Total Base Number (TBN - ASTM D2896-11). TBN is the amount of strong acid required to neutralize the alkalinity of all overly alkaline materials, expressed as potassium hydroxide equivalents (mg KOH / g sample). Since overly alkaline detergents are typically supplied in the form of a diluent oil, such as 40-50% oil, the actual TBN value of such a detergent depends on the amount of this diluent oil present, regardless of the “inherent” alkalinity of the overly alkaline material. For the purposes of this invention, the TBN of overly alkaline detergents should be recalculated on an oil-free basis. Detergents that can be used in the lubricating compositions of this invention may have a TBN of 100 to 800 (oil-free basis), 150 to 750 in one embodiment, and 400 to 700 in another embodiment. If multiple detergents are used, the total TBN of the detergent components (i.e., the average of all specific detergents) is typically within the above range.

[0033] 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). Group 1 metals in the metal compounds include Group 1a alkali metals such as sodium, potassium, and lithium, and Group 1b metals such as copper. A Group 1 metal can be sodium, potassium, lithium, or copper; in one embodiment, it is sodium or potassium, and in another embodiment, it is sodium. Group 2 metals that are basic metals include Group 2a alkaline earth metals such as magnesium, calcium, and barium, and Group 2b metals such as zinc or cadmium. In one embodiment, the Group 2 metal is magnesium, calcium, barium, or zinc; in another embodiment, it is magnesium or calcium. In some embodiments, the metal is calcium or sodium, or a mixture of calcium and sodium. Typically, the metal compound is provided as a metal salt. The anionic moiety of the salt can be hydroxide, oxide, carbonate, borate, or nitrate.

[0034] The lubricating compositions of the present invention contain an alkaline detergent. In particular, the lubricating compositions of the present invention contain one or more detergents derived from alkylphenols. In one embodiment, the metal-containing detergent derived from alkylphenols is sulfur-free.

[0035] In one embodiment, the metal-containing detergent derived from alkylphenols can be a perbasic phenolate detergent. The phenol that can be used to prepare the phenolate detergent can be derived from formula (R... 1 ) a -Ar-(OH) b It means that R 1 Ar is an aliphatic hydrocarbon group having 4 to 400 carbon atoms, or 6 to 80, 6 to 30, 8 to 25, or 8 to 15 carbon atoms; Ar is an aromatic group (which may be phenyl or other aromatic groups, such as naphthalene); a and b are independently a number of at least 1, and the sum of a and b is 2 up to the number of substituted hydrogens on one or more aromatic nuclei of Ar. In one embodiment, a and b are independently a number of 1 to 4 or 1 to 2. R 1 And a usually makes R of each phenolic compound 1 The group provides an average of at least 8 aliphatic carbon atoms. Phenolic detergents are sometimes also provided as sulfur-bridged species. The lubricating compositions of the present invention may contain at least one sulfur-free phenolic detergent. In another embodiment, the lubricating composition contains less than 0.2% by weight, or even less than 0.15% by weight, of a sulfur-coupled phenolic detergent. In another embodiment, the lubricating composition is substantially free of sulfur-coupled phenolic detergent. In yet another embodiment, the lubricating composition is free of sulfur-coupled phenolic detergent.

[0036] In one embodiment, the alkylphenol-based perbasic detergent can be a perbasic salicin detergent. Perbasic salicin detergents are typically based on perbasic magnesium salts of salicin derivatives. A general example of such salicin derivatives can be represented by formula (1):

[0037]

[0038] Where X includes -CHO or -CH2OH, Y includes -CH2- or -CH2OCH2-, wherein the -CHO group typically contains at least 10 mol% of the X and Y groups; M is the valence of hydrogen, ammonium, or a metal ion (that is, in the case of a multivalent metal ion, one valence is satisfied by the structure shown, and the other valences are satisfied by other species such as anions, or by another species with the same structure), R 1 It is a hydrocarbon group containing 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. 1 Substituents and all R 1 The total number of carbon atoms in the group is at least 7. When m is 1 or greater, one of the X groups can be hydrogen. In one embodiment, M is the valence of a Mg ion or a mixture of Mg and hydrogen. Salicylic acid detergents are disclosed in more detail in U.S. Patent 6,310,009, with particular reference to their synthesis methods (Column 8 and Example 1) and preferred amounts of various X and Y (Column 6).

[0039] In another embodiment, the alkylphenol-based overly alkaline detergent may further comprise a salixarate detergent. The salixarate detergent is an overly alkaline material that can be represented by a substantially linear compound comprising at least one unit of formula (2) or formula (3):

[0040]

[0041] Each end of this compound has a terminal group of formula (4) or (5):

[0042]

[0043] These groups are linked by divalent bridging groups A, which may be the same or different for each link; wherein in equations (2)-(5), R 3 It is the valence of hydrogen, hydrocarbon group, or metal ion; R 2 It is a hydroxyl or hydrocarbon group, j is 0, 1 or 2; R 6 It is a hydrogen, hydrocarbon group, or heterosubstituted hydrocarbon group; R 4 It is a hydroxyl group, R 5 and R 7 Independently, it is a hydrogen, hydrocarbon group, or heterosubstituted hydrocarbon group, or R 5 and R 7 Both are hydroxyl groups, R 4 It is a hydrogen, hydrocarbon group, or heterosubstituted hydrocarbon group; the condition is R. 4 R 5 R 6 and R 7At least one of them is a hydrocarbon group containing at least 8 carbon atoms; wherein the molecule contains, on average, at least one of unit (2) or (4) and at least one of unit (3) or (5), and the ratio of the total number of units (2) and (4) to the total number of units (3) and (5) in the composition is from about 0.1:1 to about 2:1. The divalent bridging group "A", which may be the same or different each time it appears, includes -CH2- (methylene bridge) and -CH2OCH2- (ether bridge), either of which may be derived from formaldehyde or formaldehyde equivalents (e.g., polyoxymethylene, formalin).

[0044] Salixarat derivatives and their preparation methods are described in more detail in U.S. Patent No. 6,200,936 and PCT Publication WO 01 / 56968. Salixarat derivatives are considered to have a predominantly linear, rather than macrocyclic, structure, although both structures are included in the term "salixarate".

[0045] The alkylphenol-based superalkaline detergent used in the lubricating compositions of the present invention may also be a superalkaline salicylate, which may be an alkali metal salt or alkaline earth metal salt of substituted salicylic acid. The salicylic acid may be a hydrocarbon-substituted salicylic acid, wherein each substituent contains an average of at least 8 carbon atoms per substituent, and each molecule contains 1 to 3 substituents. The substituents may be polyolefin substituents, wherein the polyolefins comprise homopolymers and interpolymers of polymerizable olefin monomers having 2 to 16, or 2 to 6, or 2 to 4 carbon atoms. The olefin may be a monoolefin, such as ethylene, propylene, 1-butene, isobutene, and 1-octene; or a polyolefin monomer, such as a diene monomer, such as 1,3-butadiene and isoprene. In one embodiment, one or more hydrocarbon substituents on the salicylic acid contain 7 to 300 carbon atoms and may be alkyl groups with a molecular weight of 150 to 2000. The polyolefins and polyalkyl groups are prepared by conventional procedures, and the substitution of these groups on the salicylic acid can be achieved by known methods. Alkyl salicylates can be prepared from alkylphenols via the Kolbe-Schmitt reaction; alternatively, calcium salicylate can be prepared by directly neutralizing alkylphenols followed by carbonation. Overly alkaline salicylate detergents and methods for their preparation are disclosed in U.S. Patents 4,719,023 and 3,372,116.

[0046] In addition to the metal-containing, sulfur-free detergents derived from alkylphenols as described above, the lubricating compositions of the present invention also contain a perbasic sulfonate detergent. In one embodiment, the perbasic sulfonate detergent comprises a sulfonate detergent containing an alkaline earth metal. The sulfonate detergents disclosed are known to those skilled in the art.

[0047] Sulfonate detergents are derived from sulfonic acids. Suitable sulfonic acids include sulfonic acids and thiosulfonic acids. Sulfonic acids include mononuclear or polynuclear aromatic or cyclic aliphatic compounds. Oil-soluble sulfonates can largely be represented by one of the following formulas: R 2 -T-(SO3-) a and R 3 -(SO3-) b Where T is a cyclic nucleus, such as benzene; R 2 It is an aliphatic group, such as alkyl, alkenyl, alkoxy, or alkoxyalkyl; (R 2 )-T typically contains at least 15 carbon atoms in total; R 3 It is an aliphatic hydrocarbon group that typically contains at least 15 carbon atoms. R 3 Examples are alkyl, alkenyl, alkoxyalkyl, and alkoxycarbonylalkyl groups. The groups T and R... 2 and R 3 It may also contain other inorganic or organic substituents. In the above formula, a and b are at least 1. In one embodiment, the sulfonate detergent may be a predominantly linear alkylbenzene sulfonate detergent with a metal ratio of at least 8, as described in paragraphs

[0026] -

[0037] of U.S. Patent Application 2005065045. In some embodiments, the linear alkyl group may be attached to the benzene ring at any position along the linear chain of the alkyl group, but typically at the 2, 3, or 4 position of the linear chain, and in some cases predominantly at the 2 position.

[0048] In another embodiment, the lubricating composition comprises a sulfonate detergent, such as a magnesium, sodium, or zinc perbasic sulfonate. Typically, any additional sulfonate detergent can be a magnesium sulfonate or sodium sulfonate detergent, more typically magnesium sulfonate.

[0049] In one embodiment, the lubricating composition comprises an alkaline earth metal sulfonate detergent with a metal ratio of 10 to 40 of 300 TBN or higher, and an alkaline earth metal sulfonate detergent with a metal ratio of 3 to 9 of 82 to 100 TBN or lower.

[0050] In one embodiment, the lubricating composition comprises an alkaline earth metal sulfonate detergent with a metal ratio of 10 to 40 (containing magnesium sulfonate detergent with a metal ratio of 300 TBN or higher) and an alkaline earth metal sulfonate detergent with a metal ratio of 1 to 5 (containing calcium sulfonate detergent with a metal ratio of 1 to 5).

[0051] In another embodiment, the lubricating composition comprises an alkaline earth metal sulfonate detergent with a metal ratio of 300 TBN or higher (which comprises a mixture of calcium sulfonate detergent and magnesium sulfonate detergent with a metal ratio of 10 to 40) and an alkaline earth metal sulfonate detergent with a metal ratio of 80 TBN or lower (which comprises calcium sulfonate detergent with a metal ratio of 1 to 5).

[0052] Detergents containing 300 TBN or higher alkaline earth metal sulfonates and detergents containing 80 TBN or lower alkaline earth metal sulfonates can be prepared from sulfonic acids with the same or different hydrocarbon-substituted groups. Typically, the hydrocarbon-substituted sulfonic acids are alkyl-substituted sulfonic acids.

[0053] Sulfonates can be prepared from mono- or di-alkyl-substituted benzene (or toluene, naphthalene, indene, indanyl, or dicyclopentadienyl) sulfonic acids, wherein the alkyl group may contain 6 to 40, 8 to 35, or 9 to 30 carbon atoms.

[0054] The hydrocarbon group may be derived from polypropylene or from a linear or branched alkyl group containing at least 10 carbon atoms. Examples of suitable alkyl groups include branched and / or linear decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecanyl, octadecyl, octadecenyl, nonadecanyl, eicosyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, or mixtures thereof.

[0055] In one embodiment, the hydrocarbon-substituted sulfonic acid may include polypropylene benzenesulfonic acid and C 16- C 24 Alkylbenzene sulfonic acid, or mixtures thereof.

[0056] In one embodiment, the 300TBN sulfonate detergent may be a predominantly linear alkylbenzene sulfonate detergent with a metal ratio of 10 to 40, as described in paragraphs

[0026] to

[0037] of U.S. Patent Application 2005065045 (granted US 7,407,919). Predominantly linear alkylbenzene sulfonate detergents can be particularly used to help improve fuel economy.

[0057] Typically, the metal ratio of alkaline earth metal sulfonate detergents with 300 TBN or higher is 12 to 30, or 12 to 22, or 16 to 20, or 10 to 20, or 20 to 30, or 22 to 25. In one embodiment, the 300 TBN metal ratio may be 16 to 20, and in another embodiment it is 22 to 25.

[0058] In one embodiment, the lubricating composition comprises a calcium sulfonate detergent in a metal ratio of 10 to 40 and a calcium sulfonate detergent in a metal ratio of 3 to 9.

[0059] In one embodiment, the lubricating composition comprises a calcium sulfonate detergent in a metal ratio of 10 to 40, a calcium sulfonate detergent in a metal ratio of 3 to 9, and a magnesium sulfonate detergent in a metal ratio of 12 to 40.

[0060] Magnesium sulfonate detergents may have TBN of 300 to 800, or 450 to 700 mg KOH / g; and a metal ratio of 12 to 40, or 14 to 25. Magnesium sulfonate may have sulfonic acids with the same or different hydrocarbon substitutions, and are defined in the same way as those described above for calcium sulfonate detergents.

[0061] Other overly alkaline detergents may include those having a Mannich base structure, such as those disclosed in U.S. Patent 6,569,818.

[0062] Overly alkaline materials are well known to those skilled in the art. Patents describing techniques for preparing basic salts of sulfonic acids, carboxylic acids, (hydrocarbon-substituted) phenols, phosphonic acids, and mixtures of any two or more of these include U.S. Patents 2,501,731; 2,616,905; 2,616,911; 2,616,925; 2,777,874; 3,256,186; 3,384,585; 3,365,396; 3,320,162; 3,318,809; 3,488,284; and 3,629,109.

[0063] As described above, the lubricating composition of the present invention comprises one or more metal-containing sulfur-free detergents derived from alkylphenols, in an amount sufficient to provide at least 0.2% by weight of alkylphenol-containing soap to the composition. In some embodiments, the metal-containing sulfur-free detergent may be selected from phenolate detergents, alkyl salicylates, Mg salicylates, or calcium salixarate.

[0064] The lubricating composition of the present invention further comprises one or more sulfonate detergents in an amount of at least 0.8% by weight of sulfonate soap. In one embodiment, the sulfonate detergent is an alkaline earth metal sulfonate detergent.

[0065] Succinimide dispersant

[0066] The lubricating composition further comprises a succinimide dispersant. In one embodiment, the lubricating composition comprises 1% to 4.5% by weight or 1% to 4% by weight of a polyisobutylene succinimide dispersant.

[0067] Succinimide dispersants can be derived from polyisobutylene succinimide, wherein the number average molecular weight of the polyisobutylene from which polyisobutylene succinimide can be derived is 350 to 5000, or 750 to 3000, or 1550 to 2500.

[0068] In some embodiments, the dispersant is prepared by a method involving the presence of small amounts of chlorine or other halogens, as described in U.S. Patent 7,615,521 (see, for example, column 4, lines 18-60 and Preparation Example A). Such dispersants typically have some carbocyclic structure at the connection between the hydrocarbon substituent and the acidic or amide “head” group. In other embodiments, the dispersant is prepared by a thermal method involving an “ene” reaction without the use of any chlorine or other halogens, as described in U.S. Patent 7,615,521; dispersants prepared in this manner are typically derived from high vinylene (i.e., greater than 50% terminal vinylene) polyisobutylene (see column 4, lines 61-5, line 30 and Preparation Example B). Such dispersants typically do not contain the aforementioned carbocyclic structure at the connection point. In some embodiments, the dispersant is prepared by radical-catalyzed polymerization of high vinylene polyisobutylene with an alkene-bonded unsaturated acylating agent, as described in U.S. Patent 8,067,347.

[0069] The dispersant can be derived from high-vinylene polyisobutylene as a polyolefin, i.e., having more than 50, 70, or 75% terminal vinylenes (α and β isomers). In some embodiments, the succinimide dispersant can be prepared via a direct alkylation route. In other embodiments, it may comprise a mixture of direct alkylation and chlorination dispersants.

[0070] Dispersants suitable for the compositions of the present invention include succinimidyl dispersants. In one embodiment, the dispersant may be present as a single dispersant. In another embodiment, the dispersant may be present as a mixture of two or three different dispersants, wherein at least one may be a succinimidyl dispersant.

[0071] The dispersant can also be post-treated by conventional methods through reaction with a variety of reagents. These include boron compounds, urea, thiourea, dimercaptothiadiazole, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, maleic anhydrides, nitriles, epoxides, and phosphorus compounds.

[0072] The dispersant for polyisobutylene succinimide can be derived from aliphatic polyamines or mixtures thereof. In one embodiment, the lubricating composition comprises a non-boronized succinimide dispersant.

[0073] The aliphatic polyamine can be an aliphatic polyamine, such as ethylene polyamine, propylene polyamine, butylene polyamine, or mixtures thereof. In one embodiment, the aliphatic polyamine can be an ethylene polyamine. In another embodiment, the aliphatic polyamine can be selected from ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, polyamine slurry, and mixtures thereof.

[0074] Polyisobutylene succinimide dispersants and their preparation are disclosed, for example, in U.S. Patents 3,172,892, 3,219,666, 3,316,177, 3,340,281, 3,351,552, 3,381,022, 3,433,744, 3,444,170, 3,467,668, 3,501,405, 3,542,680, 3,576,743, 3,632,511, 4,234,435, Re 26,433 and 6,165,235, 7,238,650 and EP Patent Application 0355895A.

[0075] Polyisobutylene succinimide may have a carbonyl to nitrogen ratio of 1:1 to 1:5, or 1:1 to 1:4, or 1:1.3 to 3, or 1:1.5 to 1:2, or 1:1.4 to 1:0.6.

[0076] In one embodiment, the polyisobutylene succinimide dispersant may include amine functionalized additives that may be derived from amines having at least 3 or 4 aromatic groups.

[0077] As used herein, the term "aromatic group" is used in its common sense and is known to be defined by the Hückel theory of a 4n+2π electron per ring system. Thus, an aromatic group can have 6, 10, or 14π electrons. Therefore, the benzene ring has 6π electrons, the naphthyl ring has 10π electrons, and the acridine ring has 14π electrons. Examples of amines having at least 3 or 4 aromatic groups can be represented by equation (6):

[0078]

[0079] Each variable is independent

[0080] R 1 It can be hydrogen or C 1-5 Alkyl groups (usually hydrogen);

[0081] R 2 It can be hydrogen or C 1-5 Alkyl groups (usually hydrogen);

[0082] U can be an aliphatic, alicyclic, or aromatic group, provided that when U is aliphatic, the aliphatic group can be a linear or branched alkylene group containing 1 to 5 or 1 to 2 carbon atoms; and

[0083] w can be 1 to 10, or 1 to 4, or 1 to 2 (usually 1).

[0084] Examples of amines having at least 3 or 4 aromatic groups can be represented by formula (6a):

[0085]

[0086] Each variable is independent

[0087] R 1 It can be hydrogen or C 1-5 Alkyl groups (usually hydrogen);

[0088] R 2 It can be hydrogen or C 1-5 Alkyl groups (usually hydrogen);

[0089] U can be an aliphatic, alicyclic, or aromatic group, provided that when U is aliphatic, the aliphatic group can be a linear or branched alkylene group containing 1 to 5 or 1 to 2 carbon atoms; and

[0090] w can be 1 to 10, or 1 to 4, or 1 to 2 (usually 1).

[0091] Alternatively, the compound of formula (6a) can also be represented by the following formula:

[0092]

[0093] Each variable U, R 1 and R 2 Same as above, and w can be 0 to 9, 0 to 3, or 0 to 1 (usually 0).

[0094] Examples of amines having at least 3 or 4 aromatic groups can be represented by any one of the following formulas (7) and / or (8):

[0095]

[0096] In one embodiment, the amine having at least 3 or 4 aromatic groups may comprise a mixture of compounds represented by the formulas disclosed above. Those skilled in the art will understand that the compounds of formulas (7) and (8) may also react with the aldehydes described below to form acridine derivatives. The acridine derivatives that can be formed include compounds represented by formulas (7a) or (8a) through (8c) below. In addition to the compounds represented by these formulas, those skilled in the art will also understand that other acridine structures are also possible, wherein the aldehyde reacts with other acridine structures having a benzyl group bridged to a >NH group. Examples of acridine structures include those represented by formulas (7a), (8a), or (8b) or (8c):

[0097]

[0098] Any or all N-bridged aromatic rings can be further condensed and may undergo aromatization. Another of the many possible structures includes equation (8b):

[0099]

[0100]

[0101] Any of the above formulas (7), (7a), (8) or (8a) to (8c) can also undergo further condensation reactions, resulting in the formation of one or more acridine structural moieties per molecule.

[0102] Examples of amines having at least 3 or 4 aromatic groups may be bis[p-(p-aminoanilino)phenyl]-methane, 2-(7-amino-acridin-2-ylmethyl)-N-4-{4-[4-(4-amino-phenylamino)-benzyl]-phenyl}-phenyl-1,4-diamine, N-4-{4-[4-(4-amino-phenylamino)-benzyl]-phenyl}-2-[4-(4-amino-phenylamino)-cyclohexyl-1,5-dienylmethyl]-phenyl-1,4-diamine, N-[4-(7-amino-acridin-2-ylmethyl)-phenyl]-phenyl-1,4-diamine, or mixtures thereof.

[0103] In one embodiment, the amine having at least 3 or 4 aromatic groups may be bis[p-(p-aminoaniline)phenyl]-methane, 2-(7-amino-acridin-2-ylmethyl)-N-4-{4-[4-(4-amino-phenylamino)-benzyl]-phenyl}-phenyl-1,4-diamine or a mixture thereof.

[0104] Amines having at least 3 or 4 aromatic groups can be prepared by a method involving reacting an aldehyde with an amine (typically 4-aminodiphenylamine). The resulting amine can be described as an alkylene coupling amine having at least 3 or 4 aromatic groups, at least one -NH2 functional group, and at least 2 secondary or tertiary amino groups.

[0105] Aldehydes can be aliphatic, alicyclic, or aromatic. Aliphatic aldehydes can be linear or branched. Examples of suitable aromatic aldehydes include benzaldehyde or o-vanillin. Examples of aliphatic aldehydes include formaldehyde (or its reactive equivalents, such as formalin or oligooxymethylene), acetaldehyde, or propionaldehyde. Typically, aldehydes can be formaldehyde or benzaldehyde.

[0106] Alternatively, amines having at least 3 or 4 aromatic groups can also be prepared by the method described in Berichte der DeutschenChemischen Gesellschaft (1910), 43, 728-39.

[0107] In one embodiment, an amine having at least 3 or 4 aromatic groups can be obtained / obtained by a method comprising reacting an indocyanine anhydride or an alkyl-substituted indocyanine anhydride with an aromatic amine having at least two aromatic groups and a reactive primary or secondary amino group. The resulting material can be described as an anthranilic acid derivative.

[0108] In one embodiment, the anthranilic acid derivative can be prepared by reacting an indocyanine anhydride or an alkyl-substituted indocyanine anhydride with an aromatic amine selected from phenylenediamine, 4-aminodiphenylamine, 1,4-dimethylphenylenediamine, and mixtures thereof. In one embodiment, the aromatic amine may be 4-aminodiphenylamine.

[0109] The above-described method for preparing anthranilic acid derivatives can be carried out at reaction temperatures ranging from 20°C to 180°C, or from 40°C to 110°C. The method can be carried out with or without a solvent. Examples of suitable solvents include water, diluent oil, benzene, tert-butylbenzene, toluene, xylene, chlorobenzene, hexane, tetrahydrofuran, or mixtures thereof. The reaction can be carried out in air or an inert atmosphere. Examples of suitable inert atmospheres include nitrogen or argon, typically nitrogen.

[0110] Dispersant viscosity improver

[0111] The lubricating composition of the present invention further comprises a dispersant viscosity improver. The lubricating composition comprises 0.1 to 1.2 wt% of a dispersant viscosity improver. In one embodiment, the lubricating composition comprises 0.1 to 1.2 wt% of a dispersant viscosity improver having a number average molecular weight of at least 20,000 as described herein.

[0112] Dispersant viscosity improvers may include functionalized polyolefins, such as ethylene-propylene copolymers functionalized with acylating agents such as maleic anhydride and amines; amine-functionalized polymethacrylates; or styrene-maleic anhydride copolymers reacted with amines. More detailed descriptions of dispersant viscosity improvers are disclosed in International Publication WO2006 / 015130 or U.S. Patents 4,863,623; 6,107,257; 6,107,258; 6,117,825; and US 7,790,661. In one embodiment, the dispersant viscosity improver may include those described in U.S. Patent 4,863,623 (see column 2, lines 15 through 3, lines 52) or International Publication WO2006 / 015130 (see page 2, paragraph

[0008] and preparation examples described in paragraphs

[0065] through

[0073] ).

[0113] In one specific embodiment, the dispersant viscosity improver comprises an olefin copolymer further functionalized with dispersant amine groups. Typically, the olefin copolymer may be an ethylene-propylene copolymer.

[0114] The dispersant amine group can be prepared / derived from an olefin copolymer (usually an ethylene-propylene copolymer) reacted with an acylation agent (usually maleic anhydride) and an aromatic amine having a primary or secondary amine group. Typically, the dispersant viscosity improver can be an ethylene-propylene copolymer acylated with maleic anhydride and reacted with an aromatic amine.

[0115] The formation of dispersant viscosity improvers is well known in the art. Dispersant viscosity improvers may include, for example, those described in column 2, line 48 through column 10, line 38 of U.S. Patent 7,790,661.

[0116] In one embodiment, the dispersant viscosity improver can be obtained by grafting an olefinic carboxylic acid acylated agent onto 15 to 80 mol% ethylene and 20 to 85 mol% C. 3-10 It is prepared by further reacting the grafted polymer with an amine (usually an aromatic amine) on an α-monoolefin and a polymer of 0 to 15 mol% of a non-conjugated diene or triene, the polymer having an average molecular weight of 5,000 to 500,000.

[0117] In another embodiment, the dispersant viscosity improver may be a reaction product of the following (a) and (b): (a) a polymer containing carboxylic acid functionality or a reactive equivalent thereof, the polymer having a number average molecular weight greater than 5,000; (b) an amine component comprising at least one amino group containing at least one amino group capable of condensing with the carboxylic acid functional group to provide a side group, and at least one additional group containing at least one nitrogen, oxygen, or sulfur atom, wherein the aromatic amine may be selected from (i) nitro-substituted aniline, (ii) an amine comprising two aromatic structural portions linked by a -C(O)NR- group, a -C(O)O- group, an -O- group, a -N=N- group, or a -SO2- group, wherein R may be hydrogen or a hydrocarbon group, one of the aromatic structural portions having the condensable amino group, (iii) aminoquinoline, (iv) aminobenzimidazole, (v) N,N-dialkylphenylenediamine, (vi) aminodiphenylamine (also N,N-phenylenediamine), and (vii) cyclic-substituted benzylamine.

[0118] Aromatic amines in dispersants and viscosity improvers may also include those represented by the general formula NH2-Ar or T-NH-Ar, where T may be alkyl or aromatic, and Ar may be an aromatic group, including nitrogen- or amino-substituted aromatic groups, and the Ar group includes any of the following structures.

[0119]

[0120] And multiple non-fused or connected aromatic rings. In these and related structures, R v R vi and R vii It can be independently, except for the other groups disclosed herein, -H, -C 1-18 Alkyl, nitro, -NH-Ar, -N=N-Ar, -NH-CO-Ar, -OOC-Ar, -OOC-C 1-18 Alkyl, -COO-C 18 Alkyl group, -OH, O-(CH2CH2-O)n C 1-18 Alkyl groups and -O-(CH2CH2O) n Ar (where n can be 0 to 10).

[0121] Aromatic amines include those in which the carbon atom of the aromatic ring structure is directly linked to an amino nitrogen atom. Amines can be monoamines or polyamines. The aromatic ring is usually a mononuclear aromatic ring (i.e., an aromatic ring derived from benzene), but can include fused aromatic rings, especially those derived from naphthalene. Examples of aromatic amines include aniline, N-alkylanilines such as N-methylaniline and N-butylaniline, di-(p-methylphenyl)amine, 4-aminodiphenylamine, N,N-dimethylphenyldiamine, naphthylamine, 4-(4-nitrophenylazo)aniline (Disperse Orange 3), sulphamethazine, 4-phenoxyaniline, 3-nitroaniline, 4-aminoacetaniline (N-(4-aminophenyl)acetamide), phenyl 4-amino-2-hydroxybenzoate (phenylaminosalicylate), N-(4-amino-phenyl)benzamide, various benzylamines such as 2,5-dimethoxybenzylamine, 4-phenylazoaniline, and their substituted forms. Other examples include p-ethoxyaniline, p-dodecylaniline, cyclohexyl-substituted naphthylamine, and thiophene-substituted aniline. Other suitable examples of aromatic amines include amino-substituted aromatic compounds and amines in which the amine nitrogen is part of the aromatic ring, such as 3-aminoquinoline, 5-aminoquinoline, and 8-aminoquinoline. Also included are aromatic amines such as 2-aminobenzimidazole, which contains a secondary amino group directly linked to the aromatic ring and a primary amino group linked to the imidazole ring. Other amines include N-(4-anilinophenyl)-3-aminobutyramide or 3-aminopropylimidazolium. Other amines include 2,5-dimethoxybenzylamine.

[0122] Further aromatic amines and related compounds are disclosed in U.S. Patents 6,107,257 and 6,107,258; some of which include aminocarbazole, benzimidazole, aminoindole, aminopyrrole, aminoindazolinone, aminopyrimidine, mercaptotriazole, aminophenithiazine, aminopyridine, aminopyrazine, aminopyrimidine, pyridine, pyrazine, pyrimidine, aminothiadiazole, aminothiothiadiazole, and aminobenzotriazole. Other suitable amines include 3-amino-N-(4-anilinophenyl)-N-isopropylbutyramide and N-(4-anilinophenyl)-3-{(3-aminopropyl)-(cocoyl)amino}butyramide. Other aromatic amines that can be used include various aromatic amine dye intermediates containing multiple aromatic rings linked by, for example, an amide structure. Examples include materials with the following general structures:

[0123]

[0124] and its isomer variants, of which R viii and R ixIndependently, it is an alkyl or alkoxy group, such as methyl, methoxy, or ethoxy. In one example, R viii and R ix Both are -OCH3, and the material is called FastBlue RR [CAS#6268-05-9].

[0125] In another instance, R ix It can be -OCH3 and R viii It could be -CH3, and the material is called Fast Violet B [99-21-8]. When R viii and R ix When both are ethoxylated, the material is Fast Blue BB [120-00-3]. US Patent 5,744,429 discloses other aromatic amine compounds, particularly aminoalkylphenthiazides. N-aromatic substituted amide compounds, such as those disclosed in US Patent Application 2003 / 0030033A1, can also be used for the purposes of the disclosed technology. Suitable aromatic amines include those in which the amine nitrogen is a substituent on an aromatic carboxylic acid compound, i.e., the nitrogen is not within the aromatic ring. p 2 Hybridization.

[0126] Aromatic amines may also include amines formed by reacting an aldehyde with 4-aminodiphenylamine. The resulting amine can be described as an alkylene coupling amine having at least four aromatic groups, at least one -NH2 functional group, and at least two secondary or tertiary amino groups. The aldehyde can be aliphatic, alicyclic, or aromatic. Aliphatic aldehydes can be linear or branched. Examples of suitable aromatic aldehydes include benzaldehyde or o-vanillin. Examples of aliphatic aldehydes include formaldehyde (or its reactive equivalents, such as formalin or oligooxymethylene), acetaldehyde, or propionaldehyde. Typically, the aldehyde can be formaldehyde or benzaldehyde. Alternatively, aromatic amines can also be prepared by the methods described in Berichte der Deutschen Chemischen Gesellschaft (1910), 43, 728-39.

[0127] Aromatic amines formed by coupling aldehydes and 4-aminodiphenylamine are described in European patent application EP 2401 348 A, and can also be represented by the following formula:

[0128]

[0129] Each variable

[0130] R 1 It can be hydrogen or C 1-5 Alkyl groups (usually hydrogen);

[0131] R 2 It can be hydrogen or C 1-5 Alkyl groups (usually hydrogen);

[0132] U can be an aliphatic, alicyclic, or aromatic group, provided that when U is aliphatic, the aliphatic group can be a linear or branched alkylene group containing 1 to 5 or 1 to 2 carbon atoms; and

[0133] w can be 0 to 9, 0 to 3, or 0 to 1 (usually 0).

[0134] In one embodiment, the aromatic amine includes 4-aminodiphenylamine, 4-aminodiphenylamine coupled to an aldehyde (typically formaldehyde), nitroaniline (3-nitroaniline), Disperse Orange 3 (DO3), or a mixture thereof.

[0135] The lubricating compositions of this invention comprise dispersant viscosity modifiers derived from polyolefins with a number average molecular weight of at least 20,000. In one embodiment, the lubricating composition may contain a mixture of low-molecular-weight and high-molecular-weight dispersant viscosity modifiers, provided that the total number of dispersant viscosity modifiers has a total number average molecular weight of at least 20,000. As used herein, low-molecular-weight dispersant viscosity modifiers are derived from polyolefin copolymers with a number average molecular weight of less than 20,000, or even 10,000 or lower. High-molecular-weight dispersant viscosity modifiers are derived from polyolefin copolymers with a number average molecular weight greater than 20,000, or even 40,000 or greater, or even 45,000 or greater, for example, polyolefin copolymers with a number average molecular weight of 40,000-1,000,000. For example, in one embodiment, the lubricating composition of the present invention may comprise a dispersant viscosity improver, wherein the dispersant viscosity improver comprises a mixture of at least one low molecular weight dispersant viscosity improver derived from a polyolefin with a number average molecular weight of less than 20,000 and at least one high molecular weight dispersant viscosity improver derived from a polyolefin with a number average molecular weight of at least 40,000. For example, in the above embodiment, the low molecular weight dispersant viscosity improver may be derived from a polyolefin with a number average molecular weight of 10,000. Furthermore, for example, in the above embodiment, the high molecular weight dispersant viscosity improver may be derived from a polyolefin with a number average molecular weight of 45,000 or greater.

[0136] Other performance additives

[0137] The lubricating compositions disclosed in this technology optionally include other performance additives. These other performance additives include at least one of antioxidants, metal deactivators, viscosity modifiers, friction modifiers, anti-wear agents, corrosion inhibitors, extreme pressure agents, foam inhibitors, demulsifiers, pour point depressants, sealing swelling agents, and mixtures thereof. Typically, fully formulated lubricating oils contain one or more of these performance additives.

[0138] The lubricating composition may optionally also contain at least one anti-wear agent.

[0139] Examples of suitable anti-wear agents include titanium compounds, esters, amides, and / or imides of α-hydroxycarboxylic acids (e.g., tartaric acid, malic acid, citric acid, glycolic acid), oil-soluble amine salts of phosphorus compounds, sulfurized alkenes, metal dialkyl dithiophosphates (e.g., zinc dialkyl dithiophosphate), phosphites (e.g., dibutyl phosphite), phosphonates (salts), and compounds containing thiocarbamates such as thiocarbamates, thiocarbamate amides, thiocarbamate ethers, alkylene-coupled thiocarbamates, and di(S-alkyldithiocarbamoyl) disulfides. In one embodiment, the anti-wear agent may comprise tartaric esters (salts) or tartaric imides, as disclosed in International Publication WO 2006 / 044411 or Canadian Patent CA 1 183 125. Tartaric esters (salts) or tartaric imides may contain alkyl ester groups, wherein the total number of carbon atoms on the alkyl group may be at least 8. In one embodiment, the anti-wear agent may include citrate esters (salts), as disclosed in U.S. Patent Application 20050198894.

[0140] Another class of additives includes oil-soluble titanium compounds disclosed in US 7,727,943 and US2006 / 0014651. Oil-soluble titanium compounds can be used as anti-wear agents, friction modifiers, antioxidants, deposit control additives, or one or more of these functions. In one embodiment, the oil-soluble titanium compound can be a titanium (IV) alkoxide. Titanium alkoxides can be formed from monohydric alcohols, polyhydric alcohols, or mixtures thereof. Monohydric alkoxides can have 2 to 16 or 3 to 10 carbon atoms. In one embodiment, the titanium alkoxide can be titanium isopropoxide (IV). In one embodiment, the titanium alkoxide can be titanium 2-ethylhexanoate (IV). In one embodiment, the titanium compound comprises an alkoxide of a 1,2-diol or polyol. In one embodiment, the 1,2-diol comprises a fatty acid monoester of glycerol, typically oleic acid.

[0141] In one embodiment, the oil-soluble titanium compound may be titanium carboxylate. In another embodiment, titanium carboxylate (IV) may be titanium neodecanoate.

[0142] In one embodiment, the lubricating composition may further comprise a phosphorus-containing anti-wear agent. Typically, the phosphorus-containing anti-wear agent may be a zinc dialkyl dithiophosphate, phosphite, phosphate, phosphonate, and ammonium phosphate, or a mixture thereof. Zinc dialkyl dithiophosphate is known in the art.

[0143] In one embodiment, the lubricating composition may further comprise a phosphorus-containing anti-wear agent based on zinc dialkyl dithiophosphate or a mixture thereof.

[0144] Zinc dialkyl dithiophosphate can be derived from aliphatic or aromatic hydrocarbon alcohols; the hydrocarbon group; the alcohol can be a primary or secondary alcohol. Zinc dialkyl dithiophosphate (or ZDDP) derived from a secondary alcohol is called secondary ZDDP. ZDDP derived from a primary alcohol is called primary ZDDP. ZDDP prepared from a mixture of primary and secondary alcohols is called mixed primary / secondary ZDDP. In one embodiment, ZDDP can be represented by the following structure:

[0145]

[0146] Each R can independently be a primary or secondary hydrocarbon group containing 1 to 24, for example 2 to 12 carbon atoms, including groups such as alkyl, alkenyl, aryl, aralkyl, alkylaryl, and alicyclic hydrocarbon groups. In one embodiment, R can be an alkyl group having 2 to 8 carbon atoms. In another embodiment, R can be an alkyl group having 5 or more carbon atoms. R can be, for example, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, pentyl, n-hexyl, isohexyl, n-octyl, decyl, dodecyl, octadecyl, 2-ethylhexyl, phenyl, butylphenyl, cyclohexyl, methylcyclopentyl, propenyl, and butenyl.

[0147] The R group of zinc dithiophosphate can be derived from, for example, primary alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, dodecanol, octadecanol, allyl alcohol, butenol, and 2-ethylhexanol; secondary alcohols such as isopropanol, sec-butanol, isobutanol, 3-methylbut-2-ol, 2-pentanol, 4-methyl-2-pentanol, 2-hexanol, 3-hexanol, pentanol; aryl alcohols such as phenol; substituted phenols (especially alkylphenols such as butylphenol, octylphenol, nonylphenol, and dodecylphenol); and disubstituted phenols. Certain primary glycols can also be used to prepare ZDDP; suitable primary glycols include ethylene glycol, propylene glycol, and esters of polyols such as glyceryl monooleate and combinations thereof. ZDDP can be prepared from combinations of primary alcohols and primary glycols.

[0148] In one embodiment, the R group of ZDDP may independently be a primary alkyl group, a secondary alkyl group, an aryl group, or a mixture thereof.

[0149] In one embodiment, the R group of ZDDP can be a secondary alkyl group.

[0150] When present, the amount of a metal dialkyl dithiophosphate, such as zinc dialkyl dithiophosphate, is sufficient to provide 0.1 wt% or less of phosphorus to the lubricating composition. In one embodiment, the lubricating composition contains less than 0.1 wt% of phosphorus. In another embodiment, the lubricating composition contains 0.08 wt% or less of phosphorus, for example, 0.01 wt% to 0.08 wt%. In another embodiment, the lubricating composition of the present invention contains a metal dialkyl dithiophosphate, such as ZDDP, wherein the alkyl group in the metal dialkyl dithiophosphate has 5 or more carbon atoms. In another embodiment, the lubricating composition of the present invention contains a metal dialkyl dithiophosphate, wherein at least about 65 mol% or even 75 mol% of the alkyl group has 5 or more carbon atoms.

[0151] In one embodiment, the lubricating composition of the present invention comprises a metal dialkyl dithiophosphate, wherein at least about 65 mol% or even 75 mol% of the alkyl group has 5 or more carbon atoms, such as 5 to 24 carbon atoms, or even 5 to 12 carbon atoms, or even 6 to 12 carbon atoms, wherein the lubricating composition comprises 1 wt% to 4 wt% of a polyisobutylene succinimide dispersant.

[0152] In one embodiment, the friction modifier may be selected from long-chain fatty acid derivatives of amines, long-chain fatty acid esters, or derivatives of long-chain aliphatic epoxides; aliphatic imidazolines; amine salts of alkyl phosphates; aliphatic alkyl tartrate esters; aliphatic alkyl tartrate imides; aliphatic alkyl tartrate amides; aliphatic glycolates; and aliphatic hydroxyacetamides. The friction modifier may be present in 0% to 6% by weight, or 0.01% to 4% by weight, or 0.05% to 2% by weight, or 0.1% to 2% by weight of the lubricating composition.

[0153] As used herein, the term “aliphatic alkyl” or “aliphatic” in relation to friction modifiers refers to a carbon chain having 10-22 carbon atoms, typically a linear carbon chain.

[0154] Examples of suitable friction modifiers include long-chain fatty acid derivatives of amines, aliphatic esters or aliphatic epoxides; condensation products of aliphatic imidazolines such as carboxylic acids and polyalkylene polyamines; amine salts of alkyl phosphates; aliphatic alkyl tartrate esters; aliphatic alkyl tartrate imides; aliphatic alkyl tartrate amides; aliphatic phosphonates; aliphatic phosphites; boronized phospholipids, boronized aliphatic epoxides; glycerides; boronized glycerides; aliphatic amines; alkoxylated aliphatic amines; boronized alkoxylated aliphatic amines; hydroxy and polyhydroxy aliphatic amines, including tertiary hydroxy aliphatic amines; hydroxyalkylamides; metal salts of fatty acids; metal salts of alkyl salicylates; and aliphatic... Azoline; fatty ethoxylated alcohol; condensation products of carboxylic acids and polyalkylene polyamines; or products derived from the reaction of fatty carboxylic acids with guanidine, aminoguanidine, urea or thiourea and their salts.

[0155] Friction modifiers may also include materials such as sulfurized fatty compounds and olefins, molybdenum dialkyl dithiophosphate, molybdenum dithiocarbamate, polyols, and sunflower or soybean oil monoesters of aliphatic carboxylic acids.

[0156] In another embodiment, the friction modifier may be a long-chain fatty acid ester. In another embodiment, the long-chain fatty acid ester may be a monoester; in yet another embodiment, the long-chain fatty acid ester may be a triglyceride.

[0157] Extreme pressure (EP) agents include oil-soluble compounds, including sulfur- and chlorinated sulfur-containing EP agents, CS2 derivatives of dimercaptothiadiazoles or dispersants (typically succinimide dispersants), derivatives of chlorinated hydrocarbon EP agents, and phosphorus EP agents. Examples of such EP agents include chlorinated waxes; sulfurized olefins (such as sulfurized isobutylene), hydrocarbon-substituted 2,5-dimercapto-1,3,4-thiadiazoles, or oligomers thereof, organic sulfur compounds and polysulfides such as dibenzyl disulfide, bis-(chlorobenzyl) disulfide, dibutyltetrasulfide, sulfurized methyl oleate, sulfurized alkylphenols, sulfurized dipentene, sulfurized terpenes, and sulfurized Diels-Alder adducts; phosphorus sulfurized hydrocarbons, such as the reaction products of phosphorus sulfur with turpentine or methyl oleate; phospholipids such as dihydrophosphites and trihydrophosphites, for example... Dibutyl phosphate, diheptyl phosphite, dicyclohexyl phosphite, pentylphenyl phosphite; dipentylphenyl phosphite, tridecyl phosphite, distearate phosphite, and polypropylene-substituted phenolic phosphite; metal thiocarbamates such as zinc dioctyl dithiocarbamate and barium heptaphenol diacid; amine salts or derivatives of alkyl and dialkyl phosphates, including, for example, amine salts of the reaction product of dialkyl dithiophosphite with propylene oxide and subsequently further with P2O5; and mixtures thereof (as described in US3,197,405).

[0158] Foam inhibitors that can be used in the compositions disclosed in the art include copolymers of polysiloxanes, ethyl acrylates and 2-ethylhexyl acrylates and optionally vinyl acetate; demulsifiers include fluorinated polysiloxanes, trialkyl phosphates, polyethylene glycols, polyethylene oxides, polypropylene oxides and (ethylene oxide-propylene oxide) polymers.

[0159] Pour point depressants that can be used in the compositions disclosed in the art include polyalphaolefins, esters of maleic anhydride-styrene copolymers, poly(meth)acrylates, polyacrylates, or polyacrylamide.

[0160] Demulsifiers include trialkyl phosphates, as well as various polymers and copolymers of ethylene glycol, ethylene oxide, propylene oxide, or mixtures thereof.

[0161] Metal deactivators include derivatives of benzotriazole (usually tolyltriazole), 1,2,4-triazole, benzimidazole, 2-alkyldithiobenzimidazole, or 2-alkyldithiobenzothiazole. Metal deactivators can also be described as corrosion inhibitors.

[0162] Sealing expanders include the sulfolane derivative Exxon Necton-37. TM (FN1380) and Exxon Mineral Seal Oil TM (FN 3200).

[0163] Industrial applications

[0164] The lubricating compositions of this invention can be used to lubricate any of a variety of mechanical equipment types, including but not limited to internal combustion engines, by providing them with the lubricating compositions described herein. In some embodiments, the engine may be a diesel (compression ignition) engine, such as a heavy-duty diesel engine. Other possible engines include gasoline (spark ignition) engines, as well as engines that consume alcohol, gasoline-alcohol mixtures, biodiesel fuels, various blended fuels, synthetic fuels, or gaseous fuels such as natural gas or hydrogen, two-stroke cycle engines, and marine diesel engines.

[0165] The internal combustion engines disclosed here may have steel surfaces on the cylinder bore, cylinder block, or piston rings.

[0166] Internal combustion engines may have surfaces made of steel, aluminum alloy, or aluminum composite materials.

[0167] Typically, compression-ignition internal combustion engines have a maximum load capacity of over 3,500 kg.

[0168] Compression-ignition internal combustion engines can refer to heavy-duty diesel engines. A full load weight (sometimes called gross vehicle weight rating (GVWR)) can exceed 2,700 kg (or 6,000 US pounds), or exceed 3,000 kg, or exceed 3,300 kg, or exceed 3,500 kg, or exceed 3,700 kg, or exceed 3,900 kg (or 8,500 US pounds). Typically, the upper limit for full load weight or GVWR can be set by a national government and can be 10,000 kg, or 9,000 kg, or 8,000 kg, or 7,500 kg. The upper limit range for full load weight can be as high as 400,000 kg, or up to 200,000 kg, or up to 60,000 kg, or up to 44,000 kg, or up to 40,000 kg. For off-highway vehicles, the full load capacity is typically above 120,000.

[0169] It is noted that heavy-duty diesel engines are limited to all motor vehicles with a "technically permissible maximum load capacity" exceeding 3,500 kg, equipped with compression ignition engines or forced ignition natural gas (NG) or LPG engines. In contrast, the EU states that for new light vehicles (passenger cars and light commercial vehicles) within the ACEA testing section "C" range, the "technically permissible maximum load capacity" does not exceed 2,610 kg.

[0170] There are significant differences between passenger car and heavy-duty diesel engines. The size difference, ranging from over 3,500 kg to under 2,610 kg, means the two types of engines will experience significantly different operating conditions, such as load, oil temperature, duty cycle, and engine speed. Heavy-duty diesel engines are designed to maximize traction torque for maximum fuel economy, while passenger car diesels are designed for commuting and acceleration for maximum fuel economy. This traction vs. commuting design purpose leads to different hardware designs and results in different stresses on the lubricants designed to protect and lubricate the engines. Another distinct design difference is the operating speed per minute (RPM) of each engine at traction vs. commuting. Heavy-duty diesel engines, such as typical 12-13 liter truck engines, typically do not exceed 2,200 rpm, while passenger car engines can reach 4,500 rpm.

[0171] In one implementation, the internal combustion engine may be a heavy-duty diesel compression ignition (or an electric spark assisted compression ignition) internal combustion engine.

[0172] The lubricating composition of the present invention is formulated containing the components and combinations thereof as described herein. The lubricating composition is formulated as a high-temperature, high-shear fluid having a dynamic viscosity of less than 3.5 cP, or even less than 3.1 cP, or even less than 3.05 cP, measured at 150°C according to ASTM D4683. Furthermore, the lubricating composition is formulated to have a kinematic viscosity of 10 cSt or less at 100°C, measured according to ASTM D445-17.

[0173] The following examples illustrate the invention. These examples are not exhaustive and are not intended to limit the scope of the invention. Example

[0174] A series of 10W-30 engine lubricants were prepared, containing the above-mentioned additives as well as other conventional additives known to those skilled in the art. The amounts (wt%) of each additive are shown in Table 1 below, with the balance of the lubricating composition being the base oil. The ability of the lubricating compositions to protect against adhesive wear was evaluated using ASTM WK53775. The lubricating compositions and test results are summarized in Table 1.

[0175] Table 1

[0176]

[0177] A series of 5W-30 engine lubricants were prepared, containing the above-mentioned additives as well as other conventional additives known to those skilled in the art. The amounts (wt%) of each additive are shown in Table 1 below, with the balance of the lubricating composition being the base oil. The ability of the lubricating compositions to protect against adhesive wear was evaluated using ASTM WK53775. The lubricating compositions and test results are summarized in Table 2.

[0178] Table 2

[0179]

[0180] The formulations in Examples 4, 5, and 11 particularly showed unexpectedly improved performance in terms of anti-adhesive abrasion protection.

[0181] It is known that some of the above-described materials may interact in the final formulation, such that the composition of the final formulation may differ from the initially added components. The resulting products, including those formed when the lubricant compositions of this disclosure are used for their intended purpose, may not be easily described. However, all such modifications and reaction products are included within the scope of this disclosure; this disclosure includes lubricant compositions prepared by mixing the above-described components.

[0182] As used herein, unless otherwise stated, the amounts of additives present in the lubricating compositions disclosed herein are based on oil-free, i.e., the amount of active material.

[0183] As used herein, the transitional term "comprising," synonymous with "including," "containing," or "characterized by," is inclusive or open-ended and does not exclude additional unlisted elements or method steps. However, in each statement of "comprising" herein, the term also includes, as alternative embodiments, the phrases "consistently composed of" and "composed of," wherein "composed of" excludes any unspecified elements or steps, and "consistently composed of" allows the inclusion of other undescribed elements or steps that do not substantially affect the essential, substantial, and novel characteristics of the composition or method under consideration. Additionally, as used herein, the phrase "substantially free of" means that a composition or component may include trace or contaminating amounts of material, but such material is not added in functional amounts.

[0184] As used herein, the term "compression-ignition internal combustion engine" is intended to encompass internal combustion engines with at least partial compression ignition. Therefore, the disclosed technology is intended to include methods for lubricating compression-ignition internal combustion engines and methods for using spark-assisted compression-ignition internal combustion engines.

[0185] Each document mentioned above is incorporated herein by reference. Except as expressly stated in the examples or otherwise, all values ​​for amounts of materials, reaction conditions, molecular weights, carbon numbers, etc., specified in this specification should be understood to be modified by “about”. Unless otherwise stated, each chemical or composition mentioned herein should be interpreted as a commercial-grade material that may contain isomers, byproducts, derivatives, and other such materials generally understood to be present in commercial-grade materials. However, unless otherwise stated, the amounts of each chemical component do not include any solvents or diluents commonly present in commercial materials. It should be understood that the upper and lower limits, ranges, and specific limits described herein can be combined independently. Similarly, the ranges and amounts of each element of the invention can be used in conjunction with the ranges or amounts of any other elements.

[0186] As used herein, the term "hydrocarbon substituent" or "hydrocarbon group" is used in its ordinary sense, as is well known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the rest of the molecule and having predominantly hydrocarbon properties. Examples of hydrocarbon groups include: hydrocarbon substituents, including aliphatic, alicyclic, and aromatic substituents; substituted hydrocarbon substituents, i.e., substituents containing non-hydrocarbon groups that do not alter the predominantly hydrocarbon properties of the substituent in the context of this invention; and heterosubstituents, i.e., similar substituents having predominantly hydrocarbon properties but containing elements other than carbon in the ring or chain. A more detailed definition of the term "hydrocarbon substituent" or "hydrocarbon group" is described in paragraphs

[0118] to

[0119] of PCT Publication WO2008 / 147704, or a similar definition is described in paragraphs

[0137] to

[0141] of U.S. Publication 2010-0197536.

[0187] As described below, the number-average molecular weights of dispersants, viscosity modifiers, and viscosity improvers were determined using known methods, such as GPC analysis using polystyrene standards. Methods for determining polymer molecular weights are well-known. These methods are described, for example, in: (i) P.J. Flory, “Principles of Polymer Chemistry”, Cornell University Press, 1953), Chapter VII, pp. 266-315; or (ii) “Macromolecules, an Introduction to Polymer Science”, F.A. Bovey and F.H. Winslow, Editors, Academic Press (1979), pp. 296-312.

[0188] While the invention has been described with respect to its preferred embodiments, it should be understood that various modifications will become apparent to those skilled in the art upon reading the specification. Therefore, it should be understood that the invention disclosed herein is intended to cover such modifications that fall within the scope of the appended claims.

Claims

1. A method for reducing adhesive wear in a compression engine lubricated with a low-phosphorus lubricant composition, comprising supplying a lubricant composition to the engine, said lubricant composition comprising: a) Oils with lubricating viscosity; b) One or more metal-containing sulfur-free detergents derived from alkylphenols, wherein the amount is at least 0.2% by weight of alkylphenol-containing soap provided to the composition; c) One or more alkaline earth metal sulfonate detergents, wherein the amount is at least 0.8% by weight of sulfonate soap provided to the composition; d) 1% to 4.5% by weight of one or more polyisobutylene succinimide dispersants; and e) 0.1%-1.2% by weight of dispersants and viscosity modifiers derived from polyolefins with a number average molecular weight of at least 20,000; The lubricant composition contains less than 0.2% by weight of sulfur-coupled phenolic detergent; The viscosity of the lubricant composition at 100°C is 10 centipoise or lower.

2. The method of claim 1, wherein the lubricant composition comprises less than 0.15% by weight of a sulfur-coupled phenolic detergent.

3. The method of claim 1 or 2, wherein the dispersant viscosity improver comprises a mixture of at least one low molecular weight dispersant viscosity improver and at least one high molecular weight dispersant viscosity improver, said at least one low molecular weight dispersant viscosity improver being derived from a polyolefin with a number average molecular weight of less than 20,000, and said at least one high molecular weight dispersant viscosity improver being derived from a polyolefin with a number average molecular weight of at least 40,000.

4. The method of claim 3, wherein the at least one low molecular weight dispersant viscosity improver is derived from a polyolefin with a number average molecular weight of 10,000 or lower.

5. The method of claim 3, wherein the at least one high molecular weight dispersant viscosity improver is derived from a polyolefin with a number average molecular weight of at least 45,000.

6. The method of claim 4, wherein the at least one high molecular weight dispersant viscosity improver is derived from a polyolefin with a number average molecular weight of at least 45,000.

7. The method according to any one of claims 1, 2, 4, 5 and 6, wherein the sulfur-free alkylphenol-based detergent is selected from alkylene-coupled alkylphenol detergents, alkyl salicylate detergents and combinations thereof.

8. The method of claim 7, wherein the sulfur-free alkylphenol-based detergent comprises Mg salicin.

9. The method of claim 7, wherein the sulfur-free alkylphenol-based detergent comprises Ca salixarate.

10. The method according to any one of claims 1, 2, 4, 5, 6, 8 and 9, further comprising: Metallic dialkyl dithiophosphate, wherein at least 65 mol% of the alkyl group has 5 or more carbon atoms, and is present in an amount of 0.01 to 0.08 wt% phosphorus to the composition.

11. The method according to any one of claims 1, 2, 4, 5, 6, 8 and 9, further comprising: Metallic dialkyl dithiophosphate, wherein at least 75 mol% of the alkyl group has 5 or more carbon atoms, which is present in an amount of 0.01 to 0.08 wt% phosphorus to the composition, and wherein the composition comprises 1 wt% to 4 wt% of one or more polyisobutylene succinimide dispersants.

12. The method according to any one of claims 1, 2, 4, 5, 6, 8 and 9, wherein the lubricant composition is a high-temperature, high-shear fluid having a dynamic viscosity of less than 3.05 at 150°C.

13. The method of claim 10, wherein the lubricant composition is a high-temperature, high-shear fluid having a dynamic viscosity of less than 3.05 at 150°C.

14. The method of claim 11, wherein the lubricant composition is a high-temperature, high-shear fluid having a dynamic viscosity of less than 3.05 at 150°C.

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