Magnesium sulfonate detergents with improved compatibility with friction modifiers

Abstract

The present disclosure provides a method of improving the storage stability of a lubricating composition comprising a peralkalized magnesium sulfonate detergent by post-treating the detergent with a selected hydrocarbyl-substituted succinic acid or anhydride compound.

Description

TECHNICAL FIELD

[0001] The present disclosure generally relates to lubricating oil compositions and magnesium sulfonate detergents having improved compatibility with friction modifiers for such lubricating oil compositions. BACKGROUND ART

[0002] Magnesium sulfonate is commonly used as a detergent in lubricating oil compositions for passenger cars and other vehicles. Detergents are typically used in overbased form, which are compounds having a stoichiometric excess of magnesium compared to the amount required to neutralize the sulfonic acid. However, in certain cases, prior overbased magnesium sulfonate detergents tend to have compatibility issues with other additives commonly used in lubricants. For example, overbased magnesium sulfonate detergents may have compatibility issues with common friction modifiers and especially glycerol monooleate, resulting in dropout, precipitation, and / or film formation in the oil composition. Thus, when a lubricating composition contains both overbased magnesium sulfonate and a friction modifier such as glycerol monooleate, one or more of the handling rates of such components are typically limited. Since it is often desirable to increase the level of friction modifier to improve fuel economy, the compatibility issues between these two components tend to be a limiting factor in improving the performance of lubricating compositions. SUMMARY OF THE INVENTION

[0003] According to one embodiment, a method for preparing an overbased magnesium sulfonate detergent having improved compatibility with a friction modifier is described herein. In one aspect, the method includes (a) preparing a mixture of a C14 to C24 alkylaryl sulfonic acid or its salt, magnesium oxide or magnesium hydroxide, and one or more branched C8 to C16 carboxylic acids; (b) carbonating the mixture to form an overbased magnesium sulfonate; and (c) treating the carbonated overbased magnesium sulfonate with about 6 wt% to about 10 wt% of a hydrocarbyl-substituted succinic acid or anhydride at about 160 °C to about 200 °C. In some aspects, the hydrocarbyl substituent of the hydrocarbyl-substituted succinic acid or anhydride has a number average molecular weight of about 900 to about 1500 and is derived from a polyisobutene having greater than 50 mol% terminal double bonds to form an overbased magnesium sulfonate detergent; and wherein the overbased magnesium sulfonate detergent has improved compatibility with a friction modifier.

[0004] In another method or embodiment, the method described in the previous paragraph may include other features, steps, or embodiments in any combination. These other features, steps, or embodiments may include one or more of the following: wherein the overbased magnesium sulfonate has a total base number (TBN) of at least about 450 mg KOH / g before treatment and the overbased magnesium sulfonate detergent has a total base number (TBN) of less than about 410 mg KOH / g after treatment; and / or wherein the overbased magnesium sulfonate detergent contains at least about 60 wt% of magnesium sulfonate as the active ingredient; and / or wherein the overbased magnesium sulfonate detergent has about 35 wt% or less of processing oil; and / or wherein the treatment step (c) is substantially free of dicarboxylic acids; and / or wherein the dicarboxylic acid is one or more of the following: phthalic acid, succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, malonic acid, or combinations thereof; and / or wherein before the treatment step (c), the overbased magnesium sulfonate is vacuum stripped at about 160 °C to about 200 °C; and / or wherein the overbased magnesium sulfonate detergent is storage stable at about 55 °C for at least about 18 weeks when combined with up to about 0.4 wt% of glyceryl monooleate.

[0005] In yet another method or embodiment, a storage stable overbased magnesium sulfonate detergent with improved compatibility with friction modifiers is described herein. In one aspect, the storage stable overbased magnesium sulfonate detergent is made by a method comprising the steps of: (a) preparing a mixture of a linear C14 to C24 alkylaryl sulfonic acid or its salt, magnesium oxide or hydroxide, and one or more branched C8 to C16 carboxylic acids; (b) carbonating the mixture to form an overbased magnesium sulfonate; and (c) treating the carbonated overbased magnesium sulfonate at about 160 °C to about 200 °C with about 6 wt% to about 10 wt% of a hydrocarbyl-substituted succinic acid or anhydride. In other aspects, the hydrocarbyl substituent of the hydrocarbyl-substituted succinic acid or anhydride has a number average molecular weight of about 900 to about 1500 and is derived from a polyisobutene having greater than 50 mol% terminal double bonds to form an overbased magnesium sulfonate detergent; and wherein the overbased magnesium sulfonate detergent has improved compatibility with friction modifiers.

[0006] In a further method, the storage-stable overbased magnesium sulfonate detergent of the previous paragraph comprises other features or embodiments in any combination. These other features or embodiments include one or more of the following: wherein the overbased magnesium sulfonate has a total base number (TBN) of at least about 450 mg KOH / g before treatment and the overbased magnesium sulfonate detergent has a total base number (TBN) of less than about 410 mg KOH / g after treatment; and / or wherein the overbased magnesium sulfonate detergent comprises at least about 60 wt% magnesium sulfonate as the active ingredient; and / or wherein the overbased magnesium sulfonate detergent has about 35 wt% or less of a processing oil; and / or wherein the treatment step (c) is substantially free of dicarboxylic acids; and / or wherein the dicarboxylic acid is one or more of the following: phthalic acid, succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, malonic acid, or combinations thereof; and / or wherein, prior to treatment step (c), the overbased magnesium sulfonate is vacuum stripped at about 160 °C to about 200 °C; and / or wherein the overbased magnesium sulfonate detergent has a total base number (TBN) of about 350 mg KOH / g to about 410 mg KOH / g and is storage-stable at about 55 °C for at least about 18 weeks when combined with up to about 0.4 wt% of a glycerol monooleate friction modifier.

[0007] In yet another method or embodiment, an engine oil lubricating composition is described herein that comprises a major amount of one or more base oils having lubricating viscosity, any embodiment of the storage-stable overbased magnesium sulfonate detergent described in the Summary of the Invention (e.g., from about 0.02 wt% to about 5 wt% or from about 0.2 wt% to about 2 wt%), and up to about 0.4 wt% of a glycerol monooleate friction modifier.

[0008] In yet another method or embodiment, a method of improving the storage stability of an overbased magnesium sulfonate detergent is described herein. In one aspect, the method comprises (a) preparing a mixture of a linear C14 to C24 alkylaryl sulfonic acid or its salt, magnesium oxide or magnesium hydroxide, and one or more branched C8 to C16 carboxylic acids; carbonating the mixture to form an overbased magnesium sulfonate; treating the formed overbased magnesium sulfonate with about 6 wt% to about 10 wt% of a hydrocarbyl-substituted succinic anhydride at about 160 °C to about 200 °C to form an overbased magnesium sulfonate detergent, wherein the hydrocarbyl substituent of the hydrocarbyl-substituted succinic anhydride has a number average molecular weight of about 900 to about 1500 and is derived from a polyisobutene having greater than 50 mol% terminal double bonds; and (b) combining about 0.02 wt% to about 5 wt% of the overbased magnesium sulfonate detergent with up to about 0.4 of a glycerol monooleate friction modifier; and wherein the combination of the overbased magnesium sulfonate detergent and the glycerol monooleate friction modifier is storage-stable at about 55 °C for at least about 18 weeks.

[0009] In other embodiments, the method of the previous paragraph may include additional steps, features, or embodiments in any combination. These additional steps, features, or embodiments include one or more of the following: wherein the overbased magnesium sulfonate has a total base number (TBN) of at least about 450 mg KOH / g before treatment and the overbased magnesium sulfonate detergent has a total base number (TBN) of less than about 410 mg KOH / g after treatment; and / or wherein the overbased magnesium sulfonate detergent comprises at least about 60 wt% magnesium sulfonate as the active ingredient; and / or wherein the overbased magnesium sulfonate detergent has about 35 wt% or less of processing oil; and / or wherein the treatment step (c) is substantially free of dicarboxylic acids; and / or wherein the dicarboxylic acid is one or more of the following: phthalic acid, succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, malonic acid, or combinations thereof; and / or wherein the overbased magnesium sulfonate is vacuum stripped at about 160 °C to about 200 °C before the treatment step (c); and / or wherein the overbased magnesium sulfonate detergent has a total base number (TBN) of about 350 mg KOH / g to about 410 mg KOH / g and is storage stable at about 55 °C for at least about 18 weeks when combined with up to about 0.4 wt% of a glycerol monooleate friction modifier.

[0010] In yet other methods or embodiments, the overbased magnesium sulfonate made by any method or embodiment of the present disclosure is post-treated with about 6 wt% to about 10 wt% of a hydrocarbyl-substituted succinic anhydride at about 160 °C to about 200 °C to form an overbased magnesium sulfonate detergent, and wherein the hydrocarbyl substituent of the hydrocarbyl-substituted succinic anhydride has a number average molecular weight of about 900 to about 1500 and is derived from a polyisobutene having greater than 50 mol% terminal double bonds; and wherein the combination of the post-treated overbased magnesium sulfonate detergent (e.g., about 0.02 wt% to about 5 wt%) and a glycerol monooleate friction modifier (up to about 0.4 wt%) is storage stable at about 55 °C for at least about 18 weeks. Uses may include any embodiment of the present disclosure.

[0011] Additional details and advantages of the present disclosure will be set forth in part in the following description, and / or may be learned by practice of the present disclosure. The details and advantages of the present disclosure may be realized and obtained by the elements and combinations particularly pointed out in the appended claims. It is to be understood that the foregoing general description and the following detailed description are merely exemplary and explanatory and are not restrictive of the present disclosure as claimed. Detailed Description

[0012] The present disclosure relates to an improved overbased magnesium sulfonate detergent, a method for preparing the improved overbased magnesium sulfonate detergent, and a method for improving the storage stability of an overbased magnesium sulfonate detergent. In one aspect, the methods and detergents herein produce an improved overbased magnesium sulfonate detergent having improved storage stability and / or compatibility with additives in a lubricating oil composition, and in particular, compatibility with friction modifiers such as glycerol monooleate commonly used in automotive lubricating oil compositions.

[0013] In one embodiment, a method for preparing an improved overbased magnesium sulfonate detergent having enhanced compatibility with a friction modifier (such as glycerol monooleate) is described herein. In one aspect, the method comprises: (a) preparing a reaction mixture of a C14 to C24 alkylaryl sulfonic acid or its salt, a magnesium compound, and one or more branched C8 to C16 carboxylic acids; (b) carbonating the reaction mixture to form an overbased magnesium sulfonate (carbonation is combined with the reaction mixture or is carried out after the reaction mixture is prepared); and (c) thereafter treating the carbonated overbased magnesium sulfonate at about 160 °C to about 200 °C with about 6 wt% to about 10 wt% of a hydrocarbyl-substituted succinic acid or anhydride (in other methods, about 6 wt% to about 8 wt% or about 8 wt% to about 10 wt%), and wherein the hydrocarbyl substituent of the hydrocarbyl-substituted succinic acid or anhydride has a number average molecular weight of about 900 g / mol to about 1500 g / mol (in other methods, about 900 g / mol to about 1200 g / mol) and is derived from a polyisobutene having greater than 50 mol% terminal double bonds. Such methods form an improved overbased magnesium sulfonate detergent. In another aspect, the improved overbased magnesium sulfonate detergent formed by such methods has enhanced compatibility with friction modifiers such as glycerol monooleate and / or has enhanced storage stability, as shown in the examples herein.

[0014] Prior (e.g., not post-treated as described herein) overbased detergents are well known in the art and can be alkali metal or alkaline earth metal overbased detergents. Such detergents can be prepared, for example, by reacting a metal oxide or metal hydroxide with a substrate and an overbased acid. The substrate is typically an acid and, in the case of sulfonate detergents, is a substituted sulfonic acid (e.g., an alkylaryl sulfonic acid or sulfonate). The term "overbasing" refers to the metal salts formed, such as metal salts in sulfonate form, in which the amount of metal present exceeds the stoichiometric amount. Such salts can have a conversion level of greater than 100% (i.e., they can contain greater than 100% of the theoretical amount of metal required to convert the acid substrate to its "normal" or "neutral" salt). The expression "metal ratio" is typically abbreviated as MR and is used to represent the ratio of the total chemical equivalents of metal in an overbased salt to the chemical equivalents of metal in a neutral salt, based on known chemical reactivity and stoichiometry. In a normal or neutral salt, the metal ratio is one, while in an overbased salt, the MR is greater than one. Such detergents are often referred to as overbased, superbased, or hyperbased salts and, in the case of sulfonate detergents, can be salts of organic sulfonic acids. As used herein, an overbased magnesium sulfonate detergent can have a TBN of greater than 170 mg KOH / gram, about 250 mg KOH / gram or greater, about 300 mg KOH / gram or greater, or about 350 mg KOH / gram or greater, or about 375 mg KOH / gram or greater, or about 400 mg KOH / gram or greater, or about 400 to about 410 mg KOH / gram, as measured by the method of ASTM D-2896. In other embodiments, the overbased magnesium sulfonate detergents herein have a TBN of about 175 mg KOH / gram to about 450 mg KOH / gram (or any other range therein).

[0015] In one method or embodiment, the improved overbased magnesium sulfonate detergents herein are prepared by post-treating a conventionally formed overbased magnesium sulfonate detergent with an effective amount of a selected hydrocarbyl-substituted succinic acid or anhydride under conditions effective to improve the stability of the overbased magnesium sulfonate detergent. As discussed in more detail below, it is preferred that the hydrocarbyl substituent of the succinic acid or anhydride post-treatment compound have a number average molecular weight of about 900 g / mol to about 1500 g / mol and be derived from a polyisobutene having greater than 50 mole % (in other methods, about 900 g / mol to about 1200 g / mol) terminal double bonds.

[0016] The starting conventionally formed overbased magnesium sulfonate can be prepared by methods known in the art using a one-step or two-step process. In an exemplary two-step process, first in the first step, a sulfonic acid or sulfonate (and preferably an alkylaryl sulfonic acid or sulfonate) is neutralized with a magnesium compound to produce a neutral magnesium sulfonate, and then an overbased magnesium sulfonate is formed by an additional overbasing step using additional magnesium and an overbasing acid as needed. Such two-step processes can also include water, optional promoters, base oils, and hydrocarbon solvents as needed. In most cases, the one-step process is generally preferred. In an exemplary one-step process, a sulfonic acid or sulfonate (and preferably an alkylaryl sulfonic acid or sulfonate) is combined with a molar excess of a magnesium compound, water, optional promoters, base oils, and hydrocarbon solvents. Then the overbasing acid is combined with the reaction mixture to form overbased magnesium hydroxide in a single-step process.

[0017] In one method, the starting alkylaryl sulfonic acid or sulfonate can be derived from the sulfonation of an alkyltoluene or alkylbenzene, such as a linear or branched alkyltoluene or benzene, using various known sulfonating agents such as sulfuric acid, sulfur trioxide, chlorosulfonic acid, or sulfamic acid. The alkylaryl sulfonic acid or alkylaryl sulfonate can be natural or synthetic, with synthetic alkylaryl sulfonic acids and / or alkylaryl sulfonates being preferred. The alkyl substituents in such alkylaryl moieties can have 14 or more carbon atoms, and preferably are linear or branched alkyl substituents of C14 to C24. In one method, the alkyl substituent is generally a polyolefin formed from an olefin having 2 to 5 carbon atoms, including ethylene, propylene, butene, and / or pentene monomers. In one method, the alkyl substitution is an olefin, such as a normal alpha-olefin having from about 14 to about 24 carbon atoms. More preferably, the olefin is a normal alpha-olefin having from about 20 to about 24 carbon atoms. In other methods, the alkyl substituent is a branched alkyltoluene or benzene and can be prepared by the alkylation of toluene with a branched olefin. The branched olefin can be prepared by the isomerization of a normal alpha-olefin having at least 14 carbon atoms (and preferably 14 to 24 carbon atoms). The normal alpha-olefin can be isomerized before, during, or after the alkylation step, but is preferably isomerized before the alkylation step. The methods for isomerizing olefins are known in the art. Preferably, the branched olefin is derived from the isomerization of a normal alpha-olefin having from about 14 to about 24 carbon atoms. More preferably, the branched olefin is derived from the isomerization of a normal alpha-olefin having from about 20 to about 24 carbon atoms. The branched olefin can also be derived from an oligomer of propylene or butene containing at least 9 carbon atoms, preferably from about 9 to 40 carbon atoms, more preferably from about 9 to 24 carbon atoms, and most preferably from about 10 to 18 carbon atoms.

[0018] In an embodiment, the magnesium compound provides alkalinity for overbased magnesium sulfonate and is present in a molar excess amount required stoichiometrically to react with the sulfonic acid. As noted above, the magnesium compound typically reacts in the presence of a hydrocarbon solvent and / or a low molecular weight alcohol. In one method, the magnesium compound is magnesium oxide (MgO), magnesium hydroxide (Mg(OH)₂), or a magnesium alkoxide (Mg(OR)₂), where the alkoxide is derived from an alcohol having, for example, 1 to 6 carbon atoms. Preferably, the magnesium compound is magnesium oxide or a mixture of magnesium oxide and magnesium hydroxide.

[0019] In some methods, the method of forming a conventional overbased magnesium sulfonate herein may further include a hydrocarbon solvent. Suitable hydrocarbon solvents can be n-pentane, n-hexane, cyclohexane, n-heptane, n-octane, isooctane, n-decane, benzene, toluene, xylene, or mixtures thereof. Preferably, the hydrocarbon solvent is an aromatic solvent and is xylene, benzene, toluene, or mixtures thereof, and most preferably, if used, the solvent is xylene.

[0020] In the method, the method of forming a conventional overbased magnesium sulfonate herein may further include an optional low molecular weight alcohol. If used, the low molecular weight alcohol must have a low enough boiling point such that it can be easily distilled off after the reaction has occurred. Generally, the low molecular weight alcohol will have from about 1 to about 13 carbon atoms and a molecular weight not higher than about 200. In one embodiment, the low molecular weight alcohol is a low molecular weight monohydric alcohol. In a more preferred embodiment, the low molecular weight monohydric alcohol can be selected from the group consisting of C1 to C 13 alcohols as well as glycol monoethers and monoesters. Preferably, the low molecular weight alcohol is a monohydric alcohol selected from the group consisting of: methanol, ethanol, propanol, isooctanol, cyclohexanol, cyclopentanol, isobutanol, benzyl alcohol, β-phenyl-ethanol, 2-ethylhexanol, dodecanol, tridecanol, 2-methylcyclohexanol, the monomethyl ether of ethylene glycol, the monobutyl ether of ethylene glycol, sec-pentanol, and tert-butanol. The most preferred low molecular weight monohydric alcohol is methanol (which can be added as an accelerator).

[0021] The method of forming a conventional overbased magnesium sulfonate may include an accelerator or a co-accelerator. The accelerator tends to improve acid-base contact to promote neutralization and subsequent overbasing reactions. If used, the accelerator or co-accelerator is preferably one or more monocarboxylic acids. Suitable monocarboxylic acids have 1 to 24 carbon atoms, preferably 8 to 16 carbon atoms, and most preferably 8 to 16 branched carbon chains. The monocarboxylic acid can be aliphatic or aromatic, saturated or unsaturated, and suitable monocarboxylic acids include formic acid, acetic acid, stearic acid, benzoic acid, salicylic acid, neodecanoic acid, or mixtures thereof. Preferably, the accelerator or co-accelerator is a branched C8-C16 carboxylic acid, and most preferably, the accelerator or co-accelerator is neodecanoic acid.

[0022] In the methods or embodiments herein, the method of forming the conventional overbased magnesium sulfonate herein is substantially free, and preferably free, of any promoter or co-promoter derived from or based on a hydrocarbyl-substituted succinic acid, anhydride, or their derivatives. For example, the methods herein are substantially free, and preferably free, of any promoter or co-promoter of dodecenyl succinic acid or anhydride, octadecenyl succinic acid or anhydride, and / or polyisobutylene succinic anhydride-based promoters. As used herein, "substantially free" means that the reaction mixture for forming the conventional overbased magnesium sulfonate comprises less than about 1 wt%, preferably less than about 0.5 wt%, and more preferably less than about 0.1 wt% of a hydrocarbyl-substituted succinic acid, anhydride, or derivative-based promoter or co-promoter. As used herein, "free" means that the reaction mixture for forming the conventional overbased magnesium sulfonate does not include a detectable amount of a hydrocarbyl-substituted succinic acid, anhydride, or derivative-based promoter or co-promoter. As discussed in more detail below, certain hydrocarbyl-substituted succinic acids or anhydrides are used in the post-treatment, but such post-treatment adds a promoter different from those previously used or co-promoters used during overbasing.

[0023] In the method, the overbasing acid used to form the conventional overbased magnesium sulfonate is any acid capable of providing an oil-soluble magnesium sulfonate having a greater than stoichiometric amount of magnesium relative to an alkaryl sulfonic acid or its salt. The most common overbasing acid is carbon dioxide, but other overbasing acids can include sulfur dioxide and / or sulfur trioxide. The acid itself can be part of the overbasing process, or alternatively an overbasing acid source such as ethylene carbonate can be used to introduce the overbasing acid. The most preferred acid is carbon dioxide, and the one-step or two-step method using the overbasing acid generally refers to components that are carbonated regardless of what overbasing acid may be used

[0024] An exemplary reaction scheme for forming the starting conventional overbased magnesium sulfonate is provided by Reaction Scheme I below, where R1 is hydrogen or a C1 to C4 hydrocarbyl group (preferably a methyl group), and R2 is a straight-chain or branched C14 to C24 hydrocarbyl group. As measured by the method of ASTM D-2896, the starting conventional overbased magnesium sulfonate has a total base number (TBN) greater than 170 mg KOH / gram, or as an additional example, a TBN of about 250 mg KOH / gram or greater, about 300 mg KOH / gram or greater, or about 350 mg KOH / gram or greater, or about 375 mg KOH / gram or greater, or about 400 mg KOH / gram or greater or about 400 to about 450 mg KOH / gram or greater.

[0025]

[0026] Such conventionally formed overbased magnesium sulfonates from Reaction Scheme I can also undergo a number of optional post-treatment steps (which are different from the post-treatment steps further described below). Suitable post-treatment steps can include one or more of the following: vacuum stripping, distillation, spraying, filtration, degassing, evaporation, wiped film evaporation, centrifugation, dilution, liquid-liquid extraction, membrane separation, chromatography, absorption, supercritical extraction, and / or combinations thereof, and all individual and / or combined post-treatments are typically carried out at a temperature of from about 160 °C to about 200 °C. Any such optional post-treatment steps are carried out with a selected hydrocarbyl-substituted succinic acid or anhydride prior to the post-treatment steps described more below.

[0027] As shown in the examples, such conventionally formed overbased magnesium sulfonates tend to be incompatible with friction modifiers commonly used in lubricating oil compositions and especially with glycerol monooleate. When such conventional overbased magnesium sulfonates are combined with glycerol monooleate in a lubricating oil composition, it tends to have a limited storage stability of no more than 7 to 10 weeks at about 55 °C before the formation of sloughings, deposits, and / or films. While not wishing to be bound by theory, it is believed that the inorganic magnesium core of the conventional overbased magnesium sulfonate can interact with various moieties of the friction modifier and especially with moieties of glycerol monooleate, resulting in instability of the composition and its detergent.

[0028] Post-treatment

[0029] To improve the storage stability of the conventionally formed overbased magnesium sulfonate detergent, the conventional overbased magnesium detergent is post-treated with a selected amount of a post-treatment reactant and under selected conditions, the post-treatment reactant comprising a hydrocarbyl-substituted succinic acid or anhydride and preferably having a hydrocarbyl substituent of polyisobutene having a number average molecular weight of from about 900 g / mol to about 1500 g / mol (in other methods, from about 900 g / mol to about 1200 g / mol, from about 900 g / mol to about 1100 g / mol, or from about 950 g / mol to about 1000 g / mol) and derived from a hydrocarbyl-substituted succinic acid or anhydride of polyisobutene having greater than 50 mol% terminal double bonds, as described more below.

[0030] In an embodiment, the post-treatment is carried out at a temperature of from about 160 °C to about 200 °C (in other methods, from 170 °C to about 185 °C, and in a further method, from 175 °C to about 185 °C, and most preferably about 180 °C), and is carried out using from about 6 wt% to about 10 wt% of a hydrocarbyl-substituted succinic acid or anhydride (in other methods, from about 6 wt% to about 8 wt% or from about 8 wt% to about 10 wt%). The post-treatment is carried out for from about 15 minutes to about 60 minutes, and then the mixture is cooled to from about 70 °C to about 80 °C. The post-treatment mixture typically comprises from about 60 wt% to about 70 wt% of overbased magnesium sulfonate (active base), from about 25 wt% to about 35 wt% of a processing oil, and an effective amount of the selected hydrocarbyl-substituted succinic acid or anhydride. Thus, in the embodiments herein, the improved overbased magnesium sulfonate detergent formed by the methods herein is a detergent or detergent composition comprising from about 60 wt% to about 70 wt% of overbased magnesium sulfonate (active base), from about 25 wt% to about 35 wt% of a processing oil, and from about 6 wt% to about 10 wt% (or from about 6 wt% to about 8 wt% or from about 8 wt% to about 10 wt%) of the selected hydrocarbyl-substituted succinic acid or anhydride.

[0031] Before the post-treatment, the TBN of the overbased magnesium sulfonate detergent is typically about 400 mg or KOH / gram or higher, and in some cases about 450 mg KOH / gram or higher (preferably greater than 410 to about 470 or about 420 to about 460), and after the post-treatment, the TBN of the improved overbased magnesium sulfonate detergent is typically from about 375 mg KOH / gram to about 410 mg KOH / gram (preferably, from about 400 mg KOH / gram to about 410 mg KOH / gram) or other TBN values indicated herein for overbased detergents. After the post-treatment, the KV100 of the post-treated overbased magnesium detergent (including the detergent, the processing oil, and the hydrocarbyl-substituted succinic acid or anhydride) is from about 100 centistokes to about 200 centistokes (ASTM D425), from about 125 centistokes to about 175 centistokes, or from about 140 centistokes to about 160 centistokes. As shown in the following examples, such an improved overbased magnesium sulfonate detergent is storage stable at about 55 °C for at least about 18 weeks, at least about 20 weeks, at least about 24 weeks, or longer when combined with up to about 0.4 wt% of glyceryl monooleate.

[0032] In some embodiments, the post-treatment step is substantially free of, and preferably free of, dicarboxylic acids. For example, the post-treatment step of the methods herein using a selected dicarboxylic acid is preferably substantially free of or free of dicarboxylic acids, including one or more of the following: phthalic acid, succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, malonic acid, or combinations thereof. As used herein, "substantially free of" in the context of a dicarboxylic acid during post-treatment means that the post-treatment comprises less than about 1 wt%, preferably less than about 0.5 wt%, and more preferably less than about 0.1 wt% of the dicarboxylic acid. As used herein, "free of" in the context of a dicarboxylic acid during post-treatment means that no detectable amount of any dicarboxylic acid is present.

[0033] Post-treatment agent : The post-treatment agent is a selected hydrocarbyl-substituted succinic acid or anhydride. The selected hydrocarbyl-substituted succinic acid or anhydride can be prepared as known in the art by reacting an olefinically unsaturated hydrocarbon of the indicated molecular weight with maleic acid or maleic anhydride (or analogs as discussed below) to form a hydrocarbyl-substituted succinic acid or succinic anhydride. A reaction temperature of about 100 °C to about 250 °C can be used. This reaction is often facilitated by the addition of chlorine.

[0034] The selected hydrocarbyl substituent can include olefins, such as, but not limited to, cracked wax olefins, linear alpha-olefins, branched alpha-olefins, polymers and copolymers of lower olefins. The olefins can be selected from ethylene, propylene, butenes such as isobutene, 1-octene, 1-hexene, 1-decene, etc. Some useful lower olefin polymers and / or copolymers include, but are not limited to, polypropylene, polybutene, polyisobutene, ethylene-propylene copolymer, ethylene-isobutene copolymer, propylene-isobutene copolymer, ethylene-1-decene copolymer, etc. The hydrocarbyl substituent is also made from olefin terpolymers. Available products can be made from: ethylene-C 3-12 alpha-olefin-C 5-12 non-conjugated diene terpolymers; such as ethylene-propylene-1,4-hexadiene terpolymer; ethylene-propylene-1,5-cyclooctadiene terpolymer; ethylene-propylene norbornene terpolymer, etc.

[0035] The number average molecular weight of the selected hydrocarbyl substituent of the post-treatment reactant used herein is limited to about 900 to about 1500 g / mol, in other methods, about 900 to about 1200 g / mol, and in other methods, about 950 to about 1100 g / mol, or about 950 to about 1000 g / mol, as determined by gel permeation chromatography (GPC) using polystyrene as a calibration reference as described herein. As shown in the following examples, when the resulting overbased magnesium sulfonate (even upon post-treatment) is combined with a friction modifier, the lower and higher molecular weights of the hydrocarbyl substituent unexpectedly reduce stability.

[0036] In some methods, carboxylic acid reactants other than maleic acid or maleic anhydride can also be employed to form the polycarboxylic acids or polycarboxylic anhydrides herein. Suitable reactants can also include, but are not limited to, fumaric acid, malic acid, tartaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, mesaconic acid, ethyl maleic anhydride, dimethyl maleic anhydride, ethyl maleic acid, dimethyl maleic acid, hexyl maleic acid, etc., including corresponding acid halides and lower aliphatic esters.

[0037] In some embodiments, the selected hydrocarbyl-substituted succinic anhydride or succinic acid can be prepared by the thermal reaction of a polyolefin with maleic anhydride, as described, for example, in US 3,361,673 and US 3,676,089, the disclosures of which are incorporated herein by reference. Alternatively, the substituted succinic anhydride can be prepared by the reaction of a chlorinated polyolefin with maleic anhydride, as described, for example, in US 3,172,892, the disclosure of which is also incorporated herein by reference. Further discussion of hydrocarbyl-substituted succinic anhydrides can be found, for example, in US 4,234,435; US 5,620,486 and US 5,393,309, the disclosures of which are incorporated herein by reference.

[0038] In some methods, the molar ratio of maleic anhydride (or other acylating agent) to the ethylenically unsaturated hydrocarbon can vary widely. By way of example, it can vary between about 5:1 to about 1:5, in other methods between about 3:1 to about 1:3, and in still other methods, maleic anhydride can be used in stoichiometric excess to force the reaction to completion. If desired, unreacted maleic anhydride can be removed by vacuum distillation.

[0039] In a preferred embodiment, the hydrocarbyl substituent used to form the post-treatment reactants herein is derived from polyisobutene (PIB), and most preferably a polyisobutene having a terminal double bond content of greater than 50 mol%, greater than 60 mol%, greater than 70 mol%, greater than 80 mol% or greater than 90 mol%. Such PIBs are referred to as highly reactive PIBs (“HR-PIBs”). HR-PIBs having a number average molecular weight in the range of about 900 to about 1500, as determined by GPC, are most suitable for the embodiments of the present disclosure. Conventional PIBs typically have a terminal double bond content of less than 50 mol%, less than 40 mol%, less than 30 mol%, less than 20 mol% or less than 10 mol%. Such HR-PIBs are commercially available or can be synthesized by the polymerization of isobutene in the presence of a non-chlorinated catalyst such as boron trifluoride, as described in US 4,152,499 and US 5,739,355, both of which are incorporated herein by reference.

[0040] Lubricating oil composition

[0041] The improved overbased magnesium sulfonate detergent herein can be combined with one or more additional optional additives and combined with a major amount of a base oil blend or a base oil blend having lubricating viscosity (as described below) to produce a lubricating oil composition. In the method, the lubricating oil composition contains about 50 wt% or more of the base oil blend, about 60 wt% or more, about 70 wt% or more, or about 80 wt% or more up to about 95 wt% or less, about 90 wt% or less, about 85 wt% or less of the base oil blend. The blend is further discussed below.

[0042] In the method, the lubricating oil composition herein can contain about 0.02 wt% to about 5 wt% of the improved overbased magnesium sulfonate detergent in the base oil or base oil blend. In other methods, about 0.2 wt% to about 3 wt%, and in still other methods, about 0.2 wt% to about 2 wt%. As shown in the following examples, the lubricating oil composition can also contain up to about 0.4 wt% of a friction modifier, and particularly glyceryl monooleate, and remain storage stable. Such combinations of additives (e.g., the improved overbased magnesium sulfonate detergent and glyceryl monooleate) are storage stable (e.g., free of precipitation, dropout, and / or film formation) at about 55 °C for at least about 18 weeks. As used herein, storage stable means no precipitate or film at the bottom of a 20 to 20 g sample in a clear glass vial and when observed under backlight.

[0043] The lubricants described herein, combinations of components, dispersant inhibitor packages, and / or individual components can be suitable for use in various types of lubricants, such as automotive lubricants and / or greases, internal combustion engine oils, hybrid engine oils, hybrid engine oils, electric engine lubricants, driveline lubricants, transmission lubricants, gear oils, hydraulic lubricants, tractor hydraulic fluids, metalworking fluids, turbine engine lubricants, stationary engine lubricants, tractor lubricants, motorcycle lubricants, power steering fluids, clutch fluids, shaft fluids, wet brake fluids, etc.

[0044] Suitable engine types can include, but are not limited to, heavy-duty diesel engines, passenger vehicles, light-duty diesel engines, medium-speed diesel engines, or marine engines. The internal combustion engine can be a diesel fuel engine, gasoline fuel engine, natural gas fuel engine, biofuel engine, hybrid diesel / biofuel engine, hybrid gasoline / biofuel engine, alcohol fuel engine, hybrid gasoline / alcohol fuel engine, compressed natural gas (CNG) fuel engine, or a mixture thereof. The diesel engine can be a compression ignition engine. The gasoline engine can be a spark ignition engine. The internal combustion engine can also be used in combination with a power supply or battery power source. An engine so constructed is commonly referred to as a hybrid engine. The internal combustion engine can be a two-stroke, four-stroke, or rotary engine. Suitable internal combustion engines include marine diesel engines (such as inland marine), aircraft piston engines, low-load diesel engines, and motorcycle, automotive, locomotive, and truck engines. The engine can be coupled to a turbocharger.

[0045] Regardless of the sulfur, phosphorus, or total sulfated ash (ASTM D-874) content, the lubricating oil composition for an internal combustion engine can be suitable for any engine lubricant. The sulfur content of the engine oil lubricant can be about 1 wt% or less, or about 0.8 wt% or less, or about 0.5 wt% or less, or about 0.3 wt% or less, or about 0.2 wt% or less. In one embodiment, the sulfur content can be in the range of about 0.001 wt% to about 0.5 wt%, or about 0.01 wt% to about 0.3 wt%. The phosphorus content can be about 0.2 wt% or less, or about 0.1 wt% or less, or about 0.085 wt% or less, or about 0.08 wt% or less, or even about 0.06 wt% or less, about 0.055 wt% or less, or about 0.05 wt% or less. In one embodiment, the phosphorus content can be about 50 ppm to about 1000 ppm, or about 325 ppm to about 850 ppm. The total sulfated ash content can be about 2 wt% or less, or about 1.5 wt% or less, or about 1.1 wt% or less, or about 1 wt% or less, or about 0.8 wt% or less, or about 0.5 wt% or less. In one embodiment, the sulfated ash content can be about 0.05 wt% to about 0.9 wt%, or about 0.1 wt% to about 0.2 wt% to about 0.45 wt%. In another embodiment, the sulfur content can be about 0.4 wt% or less, the phosphorus content can be about 0.08 wt% or less, and the total sulfated ash is about 1 wt% or less. In yet another embodiment, the sulfur content can be about 0.3 wt% or less, the phosphorus content is about 0.05 wt% or less, and the total sulfated ash can be about 0.8 wt% or less.

[0046] In addition, the lubricants of the present specification may be adapted to meet one or more industry specification requirements, such as ILSAC GF-3, GF-4, GF-5, GF-6, PC-11, CF, CF-4, CH-4, CK-4, FA-4, CJ-4, CI-4Plus, CI-4, API SG, SJ, SL, SM, SN, SN PLUS, ACEA A1 / B1, A2 / B2, A3 / B3, A3 / B4, A5 / B5, C1, C2, C3, C4, C5, E4 / E6 / E7 / E9, Euro 5 / 6, JASO DL-1, Low SAPS, Mid SAPS, or original equipment manufacturer specifications, such as Dexos1TM, Dexos2TM, MB-Approval 229.1, 229.3, 229.5, 229.51 / 229.31, 229.52, 229.6, 229.71, 226.5, 226.51, 228.0 / .1, 228.2 / .3, 228.31, 228.5, 228.51, 228.61, VW 501.01, 502.00, 503.00 / 503.01, 504.00, 505.00, 505.01, 506.00 / 506.01, 507.00, 508.00, 509.00, 508.88, 509.99, BMW Longlife-01, Longlife-01FE, Longlife-04, Longlife-12FE, Longlife-14FE+, Longlife-17FE+, Porsche A40, C30, Peugeot Automobiles B71 2290, B71 2294, B71 2295, B71 2296, B71 2297, B71 2300, B71 2302, B71 2312, B71 2007, B71 2008, Renault RN0700, RN0710, RN0720, Ford WSS-M2C153-H, WSS-M2C930-A, WSS-M2C945-A, WSS-M2C913A, WSS-M2C913-B, WSS-M2C913-C, WSS-M2C913-D, WSS-M2C948-B, WSS-M2C948-A, GM6094-M, Chrysler MS-6395, Fiat 9.55535G1, G2, M2, N1, N2, Z2, S1, S2, S3, S4, T2, DS1, DSX, GH2, GS1, GSX, CR1, Jaguar Land Rover STJLR.03.5003, STJLR.03.5004, STJLR.03.5005, STJLR.03.5006, STJLR.03.5007, STJLR.51.5122 or any past or future PCMO or HDD specification not mentioned herein. In some embodiments, for passenger car motor oil (PCMO) applications, the amount of phosphorus in the finished fluid is 1000 ppm or less, or 900 ppm or less, or 800 ppm or less.

[0047] Base oil or base oil blend : The base oil for use in the lubricating oil composition herein can be an oil having lubricating viscosity and is selected from any one of Group I to Group V base oils as defined in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. The five base oil groups are generally listed in Table 1 below:

[0048] Table 1

[0049]

[0050] Groups I, II, and III are raw materials for mineral oil treatment. Group IV base oils contain true synthetic molecular substances, which are prepared by polymerization of olefinically unsaturated hydrocarbons. Many Group V base oils are also true synthetic products and may include diesters, polyol esters, polyalkylene glycols, alkylated aromatics, polyphosphates, polyethylene ethers, and / or polyphenylene ethers, etc., but may also be naturally occurring oils such as vegetable oils. It should be noted that although Group III base oils are derived from mineral oils, the rigorous treatment these fluids undergo results in their physical properties being very similar to some true synthetic oils such as PAO. Therefore, oils derived from Group III base oils can be referred to as synthetic fluids in the industry. Group II+ may include Group II with a high viscosity index.

[0051] The base oil blend for the disclosed lubricating oil composition can be a mineral oil, an animal oil, a vegetable oil, a synthetic oil, a synthetic oil blend, or a mixture thereof. Suitable oils can be derived from hydrocracked, hydrogenated, hydrorefined, unrefined, refined, and re-refined oils, and mixtures thereof.

[0052] Unrefined oils are those oils derived from natural, mineral, or synthetic sources without or with very little further purification treatment. Refined oils are similar to unrefined oils, except that they have been treated with one or more purification steps, which may result in the improvement of one or more properties. Examples of suitable purification techniques are solvent extraction, secondary distillation, acid or base extraction, filtration, percolation, etc. Oils refined to edible quality may or may not be useful. Edible oils can also be referred to as white oils. In some embodiments, the lubricating oil composition does not contain edible oils or white oils.

[0053] Re-refined oils are also called recycled oils or reprocessed oils. Similar to refined oils, these oils are obtained using the same or similar processes. Generally, these oils are further treated by techniques aimed at removing waste additives and oil decomposition products.

[0054] Mineral oils can include oils obtained by drilling or oils from plants and animals, or any mixture thereof. For example, such oils can include, but are not limited to, castor oil, lard, olive oil, peanut oil, corn oil, soybean oil, and linseed oil, as well as mineral lubricating oils such as liquid petroleum and solvent-treated or acid-treated paraffinic, naphthenic, or mixed paraffinic-naphthenic type mineral lubricating oils. If desired, such oils can be partially or fully hydrogenated. Oils derived from coal or shale can also be useful.

[0055] Useful synthetic lubricating oils can include hydrocarbon oils such as polymerized, oligomerized or copolymerized olefins (e.g., polybutene, polypropylene, propylene-isobutylene copolymer); poly(1-hexene), poly(1-octene), trimers or oligomers of 1-decene such as poly(1-decene), such materials are commonly referred to as alpha-olefins, and mixtures thereof; alkyl-benzenes (e.g., dodecylbenzene, tetradecylbenzene, dinonylbenzene, di-(2-ethylhexyl)-benzene); polyphenyls (e.g., biphenyl, terphenyl, alkylated polyphenyl); diphenylalkanes, alkylated diphenylalkanes, alkylated diphenyl ethers and alkylated diphenyl sulfides and their derivatives, analogs and homologs or mixtures thereof. Polyalpha-olefins are typically hydrogenated materials.

[0056] Other synthetic lubricating oils include polyol esters containing phosphoric acid, diesters, liquid esters (e.g., tolyl phosphate, trioctyl phosphate and diethyl decylphosphonate) or polytetrahydrofuran. Synthetic oils can be produced by the Fischer-Tropsch reaction and can generally be hydroisomerized Fischer-Tropsch hydrocarbons or waxes. In one embodiment, the oil can be prepared by a Fischer-Tropsch gas-liquid synthesis process as well as other gas-liquid oils.

[0057] The major amount of base oil included in the lubricating composition can be selected from Group I, Group II, Group III, Group IV, Group V and combinations of two or more of the foregoing, and wherein the major amount of base oil is different from the base oil produced by providing additive components or viscosity index improvers in the composition. In another embodiment, the major amount of base oil included in the lubricating composition can be selected from Group II, Group III, Group IV, Group V and combinations of two or more of the foregoing, and wherein the major amount of base oil is different from the base oil produced by providing additive components or viscosity index improvers in the composition.

[0058] The amount of oil having lubricating viscosity can be the balance remaining after subtracting the total amount of performance additives (including viscosity index improvers and / or pour point depressants and / or other top treatment additives) from 100 weight%. For example, the oil having lubricating viscosity that can be present in the finished fluid can be a major amount, such as greater than about 50 weight%, greater than about 60 weight%, greater than about 70 weight%, greater than about 80 weight%, greater than about 85 weight% or greater than about 90 weight%.

[0059] Optional additive :

[0060] The lubricating oil compositions herein can also optionally include many optional additives in combination with optionally overbased and sulfided alkylphenate products as needed to meet performance criteria. Those optional additives are described in the following paragraphs.

[0061] Dispersant : The lubricating oil composition may optionally contain one or more dispersants or mixtures thereof. Dispersants are commonly referred to as ashless dispersants because they do not contain ash-forming metals before being incorporated into the lubricating oil composition and generally do not provide any ash when added to the lubricant. 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. Examples of N-substituted long-chain alkenyl succinimides include polyisobutylene succinimides, wherein the number average molecular weight of the polyisobutylene substituent, as measured by GPC, is in the range of about 350 to about 50,000 or up to about 5,000 or up to about 3,000. Succinimide dispersants and their preparation are disclosed, for example, in U.S. Patent No. 7,897,696 or U.S. Patent No. 4,234,435. The alkenyl substituents can be prepared from polymerizable monomers containing about 2 to about 16, or about 2 to about 8, or about 2 to about 6 carbon atoms. Succinimide dispersants are generally imides formed from polyamines, typically poly(ethyleneamine).

[0062] Preferred amines are selected from polyamines and hydroxylamines. Examples of polyamines that can be used include, but are not limited to, diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), and higher homologues such as pentaethylenehexamine (PEHA), etc.

[0063] Suitable heavy polyamines are mixtures of polyalkylene-polyamines containing small amounts of lower polyamine oligomers such as TEPA and PEHA (pentaethylenehexamine) but mainly oligomers having 6 or more nitrogen atoms per molecule, 2 or more primary amines, and more extensive branching than conventional polyamine mixtures. The heavy polyamines preferably include polyamine oligomers containing 7 or more nitrogen per molecule and 2 or more primary amines per molecule. The heavy polyamines contain greater than 28 wt% (e.g., >32 wt%) total nitrogen and an equivalent weight of primary amine groups of 120 g / equivalent - 160 g / equivalent.

[0064] In some methods, suitable polyamines are commonly referred to as PAM and contain mixtures of ethyleneamines, where TEPA and pentaethylenehexamine (PEHA) are the major parts of the polyamines, usually less than about 80%.

[0065] Typically, PAM has a primary amine content of 8.7 meq / g to 8.9 meq / g (equivalent weight of primary amine is 115 g / equivalent to 112 g / equivalent) and a total nitrogen content of about 33 wt% to 34 wt%. Heavier PAM oligomer cuts have little TEPA and only very small amounts of PEHA, but mainly contain oligomers with more than 6 nitrogens and more extensive branching, which can produce dispersants with improved dispersibility.

[0066] In one embodiment, the present disclosure also includes at least one polyisobutylene succinimide dispersant derived from polyisobutylene having a number average molecular weight in the range of about 350 to about 50,000 or up to about 5000 or up to about 3000, as determined by GPC. The polyisobutylene succinimide can be used alone or in combination with other dispersants.

[0067] In some embodiments, the polyisobutylene (when included) can have a terminal double bond content greater than 50 mol%, greater than 60 mol%, greater than 70 mol%, greater than 80 mol%, or greater than 90 mol%. Such PIB is also referred to as highly reactive PIB (“HR-PIB”). HR-PIB having a number average molecular weight in the range of about 800 to about 5000, as determined by GPC, is suitable for embodiments of the present disclosure. Conventional PIB typically has a terminal double bond content less than 50 mol%, less than 40 mol%, less than 30 mol%, less than 20 mol%, or less than 10 mol%.

[0068] HR-PIB having a number average molecular weight in the range of about 900 to about 3000, as determined by GPC, can be suitable. Such HR-PIB is commercially available or can be synthesized by polymerizing isobutylene in the presence of a non-chlorinated catalyst such as boron trifluoride, as described in U.S. Patent Nos. 4,152,499 to Boerzel et al. and 5,739,355 to Gateau et al. When used in the aforementioned thermal ene reaction, due to enhanced reactivity, HR-PIB can increase the conversion in the reaction and reduce the amount of sediment formation. Suitable methods are described in U.S. Patent No. 7,897,696.

[0069] In one embodiment, the present disclosure also includes at least one dispersant derived from polyisobutylene succinic anhydride (“PIBSA”). PIBSA can have from about 1.0 to about 2.0 succinic acid moieties per polymer on average.

[0070] Chromatographic techniques can be used to determine the active % of alkenyl or alkyl succinic anhydrides. This method is described in columns 5 and 6 of U.S. Patent No. 5,334,321.

[0071] Using the equations in columns 5 and 6 of U.S. Patent No. 5,334,321, the conversion percentage of the polyolefin is calculated from the active %.

[0072] Unless otherwise specified, all percentages are by weight (wt%) and all molecular weights are number average molecular weights determined by gel permeation chromatography (GPC) using commercially available polystyrene standards (with a number average molecular weight from 180 to about 18,000 as the calibration reference).

[0073] In one embodiment, the dispersant may be derived from polyalphaolefin (PAO) succinic anhydride. In one embodiment, the dispersant may be derived from an olefin maleic anhydride copolymer. For example, the dispersant may be described as polyPIBSA. In one embodiment, the dispersant may be derived from an anhydride grafted to an ethylene-propylene copolymer.

[0074] Suitable classes of nitrogen-containing dispersants may be derived from olefin copolymer (OCP), and more specifically, ethylene-propylene dispersants, which may be grafted with maleic anhydride. A more complete list of nitrogen-containing compounds that may react with the functionalized OCP is described in U.S. Patent Nos. 7,485,603; 7,786,057; 7,253,231; 6,107,257; and 5,075,383; and / or are commercially available.

[0075] One suitable class of dispersants may also be Mannich bases. Mannich bases are substances formed by the condensation of a higher molecular weight alkyl-substituted phenol, a polyalkylene polyamine, and an aldehyde such as formaldehyde. Mannich bases are described in more detail in U.S. Patent No. 3,634,515.

[0076] One suitable class of dispersants may also be high molecular weight esters or semi-ester amides. Suitable dispersants may also be post-treated by reacting with any one of a variety of reagents by conventional methods. Among these are boron, urea, thiourea, dimercaptothiadiazole, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, maleic anhydrides, nitriles, epoxides, carbonates, cyclic carbonates, hindered phenol esters, and phosphorus compounds. US 7,645,726; US 7,214,649; and US 8,048,831 are hereby incorporated by reference in their entireties.

[0077] In addition to carbonate and borate post-treatments, both compounds can be post-treated or further post-treated with a variety of post-treatment methods designed to improve or impart different properties. Such post-treatments include those outlined in columns 27 to 29 of U.S. Patent No. 5,241,003, which are incorporated herein by reference. Such treatments include treatment with: inorganic phosphorous acid or anhydrides (e.g., U.S. Patent Nos. 3,403,102 and 4,648,980); organic phosphorus compounds (e.g., U.S. Patent No. 3,502,677); phosphorus pentasulfide; boron compounds as described above (e.g., U.S. Patent Nos. 3,178,663 and 4,652,387); carboxylic acids, polycarboxylic acids, acid anhydrides, and / or acid halides (e.g., U.S. Patent Nos. 3,708,522 and 4,948,386); epoxides, polyepoxides, or thioepoxides (e.g., U.S. Patent Nos. 3,859,318 and 5,026,495); aldehydes or ketones (e.g., U.S. Patent No. 3,458,530); carbon disulfide (e.g., U.S. Patent No. 3,256,185); glycidol (e.g., U.S. Patent No. 4,617,137); ureas, thioureas, or guanidines (e.g., U.S. Patent Nos. 3,312,619; 3,865,813; and British Patent GB 1,065,595); organic sulfonic acids (e.g., U.S. Patent No. 3,189,544 and British Patent GB 2,140,811); vinyl cyanides (e.g., U.S. Patent Nos. 3,278,550 and 3,366,569); diketenes (e.g., U.S. Patent No. 3,546,243); diisocyanates (e.g., U.S. Patent No. 3,573,205); alkane sultones (e.g., U.S. Patent No. 3,749,695); 1,3-dicarbonyl compounds (e.g., U.S. Patent No. 4,579,675); sulfates of alkoxylated alcohols or phenols (e.g., U.S. Patent No. 3,954,639); cyclic lactones (e.g., U.S. Patent Nos. 4,617,138; 4,645,515; 4,668,246; 4,963,275; and 4,971,711); cyclic carbonates or thiocarbonates, linear monocarbonates or polycarbonates, or chloroformates (e.g., U.S. Patent Nos. 4,612,132; 4,647,390; 4,648,886; 4,670,170); nitrogen-containing carboxylic acids (e.g., U.S. Patent No. 4,971,598 and British Patent GB 2,140,811); hydroxy-protected chlorodicarbonyl-oxy compounds (e.g., U.S. Patent No. 4,614,522); lactams, thiolactams, thiolactones, or dithiolactones (e.g., U.S. Patent Nos. 4,614,603 and 4,666,460); cyclic carbonates or thiocarbonates, linear monocarbonates or polycarbonates, or chloroformates (e.g., U.S. Patent Nos. 4,612,132; 4,647,390; 4,646,860; and 4,670,170);Nitrogen-containing carboxylic acids (e.g., U.S. Patent No. 4,971,598 and British Patent GB 2,440,811); hydroxy-protected chlorodicarbonyl oxy compounds (e.g., U.S. Patent No. 4,614,522); lactams, thiolactams, thiolactones or dithiolactones (e.g., U.S. Patent Nos. 4,614,603 and 4,666,460); cyclic carbamates, cyclic thiocarbamates or cyclic dithiocarbamates (e.g., U.S. Patent Nos. 4,663,062 and 4,666,459); hydroxy aliphatic carboxylic acids (e.g., U.S. Patent Nos. 4,482,464; 4,521,318; 4,713,189); oxidizing agents (e.g., U.S. Patent No. 4,379,064); combinations of phosphorus pentasulfide and polyalkylene polyamines (e.g., U.S. Patent No. 3,185,647); combinations of carboxylic acids or aldehydes or ketones and sulfur or sulfur chloride (e.g., U.S. Patent Nos. 3,390,086; 3,470,098); combinations of hydrazine and carbon disulfide (e.g., U.S. Patent No. 3,519,564); combinations of aldehydes and phenols (e.g., U.S. Patent Nos. 3,649,229; 5,030,249; 5,039,307); combinations of aldehydes and O-diesters of dithiophosphoric acid (e.g., U.S. Patent No. 3,865,740); combinations of hydroxy aliphatic carboxylic acids and boric acid (e.g., U.S. Patent No. 4,554,086); hydroxy aliphatic carboxylic acids, then combinations of formaldehyde and phenols (e.g., U.S. Patent No. 4,636,322); combinations of hydroxy aliphatic carboxylic acids with then aliphatic dicarboxylic acids (e.g., U.S. Patent No. 4,663,064); combinations of formaldehyde and phenols with then glycolic acid (e.g., U.S. Patent No. 4,699,724); combinations of hydroxy aliphatic carboxylic acids or oxalic acid, and then diisocyanates (e.g., U.S. Patent No. 4,713,191); combinations of inorganic acids or anhydrides of phosphorus or partial or total sulfur analogues thereof with boron compounds (e.g., U.S. Patent No. 4,857,214); combinations of organic diacids, then unsaturated fatty acids with then nitroso aromatic amines, optionally subsequently boron compounds and then ethanolating reagents (e.g., U.S. Patent No. 4,973,412); combinations of aldehydes and triazoles (e.g., U.S. Patent No. 4,963,278); combinations of aldehydes and triazoles, then boron compounds (e.g., U.S. Patent No. 4,981,492); combinations of cyclic lactones and boron compounds (e.g., U.S. Patent Nos. 4,963,275 and 4,971,711). The patents mentioned above are incorporated herein by reference in their entirety.;

[0078] The TBN of a suitable dispersant can be from about 10 mg KOH / g to about 65 mg KOH / g dispersant on an oil-free basis, which is equivalent to about 5 TBN to about 30 TBN if measured on a dispersant sample containing about 50% dilution oil. TBN is measured by the method of ASTM D2896.

[0079] In still other embodiments, the optional dispersant additive can be a hydrocarbyl-substituted succinamide or succinimide dispersant. In the method, the hydrocarbyl-substituted succinamide or succinimide dispersant is derived from a hydrocarbyl-substituted acylating agent reacted with a polyalkylene polyamine, and wherein the hydrocarbyl substituent of the succinamide or succinimide dispersant is a linear or branched hydrocarbyl group having a number average molecular weight of from about 250 to about 5,000 as measured by GPC using polystyrene as a calibration reference.

[0080] In some methods, the polyalkylene polyamine used to form the dispersant has the formula

[0081]

[0082] wherein each R and R' is independently a divalent C1 to C6 alkylene linking group, each R1 and R2 is independently hydrogen, a C1 to C6 alkyl group or together with the nitrogen atom to which they are attached forms a 5- or 6-membered ring optionally fused to one or more aromatic or non-aromatic rings, and n is an integer between 0 and 8. In other methods, the polyalkylene polyamine is selected from the group consisting of mixtures of polyethylene polyamines having on average 5 to 7 nitrogen atoms, triethylene tetramine, tetraethylene pentamine, and combinations thereof.

[0083] If present, the dispersant can be used in an amount sufficient to provide up to about 20 wt% based on the final weight of the lubricating oil composition. Another amount of the dispersant that can be used is from about 0.1 wt% to about 15 wt%, or from about 0.1 wt% to about 10 wt%, or from about 0.1 wt% to about 8 wt%, or from about 1 wt% to about 10 wt%, or from about 1 wt% to about 8 wt%, or from about 1 wt% to about 6 wt% based on the final weight of the lubricating oil composition. In some embodiments, the lubricating oil composition utilizes a mixed dispersant system. A single type of dispersant or a mixture of two or more types of dispersants can be used in any desired ratio.

[0084] Antioxidant The lubricating oil composition herein may also optionally contain one or more antioxidants. Antioxidant compounds are known and include, for example, phenates, phenate sulfides, sulfurized olefins, sulfurized terpenes, sulfurized esters, aromatic amines, alkylated diphenylamines (e.g., nonyl diphenylamine, dinonyl diphenylamine, octyl diphenylamine, dioctyl diphenylamine), phenyl-α-naphthylamine, alkylated phenyl-α-naphthylamine, hindered non-aromatic amines, phenols, hindered phenols, oil-soluble molybdenum compounds, macromolecular antioxidants, or mixtures thereof. The antioxidant compounds can be used alone or in combination.

[0085] The hindered phenol antioxidant may contain secondary butyl and / or tertiary butyl as sterically hindered groups. The phenolic group may also be substituted by a hydrocarbon group and / or a bridging group linking to a second aromatic group. Examples of suitable hindered phenol antioxidants include 2,6-di-tert-butylphenol, 4-methyl-2,6-di-tert-butylphenol, 4-ethyl-2,6-di-tert-butylphenol, 4-propyl-2,6-di-tert-butylphenol or 4-butyl-2,6-di-tert-butylphenol, or 4-dodecyl-2,6-di-tert-butylphenol. In one embodiment, the hindered phenol antioxidant may be an ester and may include, for example, Irganox TM L-135 or an addition product derived from 2,6-di-tert-butylphenol and an alkyl acrylate, wherein the alkyl group may contain about 1 to about 18, or about 2 to about 12, or about 2 to about 8, or about 2 to about 6, or about 4 carbon atoms. Another commercially available hindered phenol antioxidant may be an ester and may include Ethanox TM 4716.

[0086] Available antioxidants may include diarylamines and high molecular weight phenols. In one embodiment, the lubricating oil composition may contain a mixture of diarylamines and high molecular weight phenols such that each antioxidant may be present in an amount sufficient to provide up to about 5 wt% based on the final weight of the lubricating oil composition. In one embodiment, based on the final weight of the lubricating oil composition, the antioxidant may be a mixture of about 0.3 wt% to about 1.5 wt% diarylamine and about 0.4 wt% to about 2.5 wt% high molecular weight phenol.

[0087] Examples of suitable olefins that can be sulfided to form sulfurized olefins include propylene, butylene, isobutylene, polyisobutylene, pentene, hexene, heptene, octene, nonene, decene, undecene, dodecene, tridecene, tetradecene, pentadecene, hexadecene, heptadecene, octadecene, nonadecene, eicosene or mixtures thereof. In one embodiment, hexadecene, heptadecene, octadecene, nonadecene, eicosene or mixtures thereof, and their dimers, trimers and tetramers are particularly suitable olefins. Alternatively, the olefin may be a Diels-Alder adduct of a diene (such as 1,3-butadiene) and an unsaturated ester (such as butyl acrylate).

[0088] Another class of sulfurized olefins includes sulfurized fatty acids and their esters. Fatty acids are typically obtained from vegetable or animal oils and generally contain from about 4 to about 22 carbon atoms. Examples of suitable fatty acids and their esters include triglycerides, oleic acid, linoleic acid, palmitoleic acid, or mixtures thereof. Typically, the fatty acids are obtained from lard, pine oil, peanut oil, soybean oil, cottonseed oil, sunflower seed oil, or mixtures thereof. The fatty acids and / or esters may be blended with olefins such as alpha-olefins.

[0089] In another alternative embodiment, in addition to the phenolic and / or amine antioxidants discussed above, the antioxidant composition further contains a molybdenum-containing antioxidant. When using a combination of these three antioxidants, preferably, the ratio of the phenolic antioxidant to the amine antioxidant to the molybdenum-containing antioxidant is (0 to 2):(0 to 2):(0 to 1).

[0090] The one or more antioxidants may be present in the lubricating oil composition in the range of from about 0 wt% to about 20 wt%, or from about 0.1 wt% to about 10 wt%, or from about 1 wt% to about 5 wt%.

[0091] Antiwear agent The lubricating oil compositions herein may also optionally contain one or more antiwear agents. Examples of suitable antiwear agents include, but are not limited to, metal thiophosphates; metal dialkyldithiophosphates; phosphate esters or their salts; phosphate esters; phosphite esters; phosphorus-containing carboxylic esters, ethers or amides; sulfurized olefins; compounds containing thiocarbamates, including thiocarbamates, alkylene-coupled thiocarbamates and bis(S-alkyldithiocarbamoyl) disulfides; and mixtures thereof. A suitable antiwear agent may be molybdenum dithiocarbamate. Phosphorus-containing antiwear agents are more fully described in European Patent 612 839. The metal in the dialkyldithiophosphates may be an alkali metal, alkaline earth metal, aluminum, lead, tin, molybdenum, manganese, nickel, copper, titanium or zinc. A suitable antiwear agent may be zinc dialkyldithiophosphate.

[0092] Other examples of suitable antiwear agents include titanium compounds, tartrate esters, tartramides, oil-soluble amine salts of phosphorus compounds, sulfurized olefins, phosphite esters such as dibutyl phosphite, phosphonate esters, compounds containing thiocarbamates such as thiocarbamates, thiocarbamate amides, thiocarbamate ethers, alkylene-coupled thiocarbamates and bis(S-alkyldithiocarbamoyl) disulfides. The tartrate esters or tartramides may contain alkyl ester groups, where the total number of carbon atoms in the alkyl group may be at least 8. In one embodiment, the antiwear agent may include citrate esters.

[0093] An antiwear agent may be present in an amount ranging from about 0 wt% to about 15 wt%, or about 0.01 wt% to about 10 wt%, or about 0.05 wt% to about 5 wt%, or about 0.1 wt% to about 3 wt% of the lubricating oil composition.

[0094] Boron-containing compound : The lubricating oil composition herein may optionally contain one or more boron-containing compounds. Examples of boron-containing compounds include borate esters, boronated fatty amines, boronated epoxides, boronated detergents, and boronated dispersants, such as boronated succinimide dispersants, as disclosed in U.S. Patent No. 5,883,057. The boron-containing compound, if present, may be used in an amount sufficient to provide up to about 8 wt%, about 0.01 wt% to about 7 wt%, about 0.05 wt% to about 5 wt%, or about 0.1 wt% to about 3 wt% of the lubricating oil composition.

[0095] Additional detergent : The lubricating oil composition may optionally further contain one or more neutral, low-alkalized, or over-alkalized detergents and mixtures thereof. Suitable detergent bases include benzoates, sulfur-containing benzoates, sulfonates, calixates, salicylates, carboxylates, phosphoric acid, monothiophosphoric acid, and / or dithiophosphoric acid, alkylphenols, sulfur-coupled alkylphenol compounds, or methylene-bridged phenols. Suitable detergents and methods for their preparation are described in more detail in a number of patent disclosures, including US 7,732,390 and the references cited therein.

[0096] The detergent base can be salified with alkali metals or alkaline earth metals such as, but not limited to, calcium, magnesium, potassium, sodium, lithium, barium, or mixtures thereof. In some embodiments, the detergent is free of barium. In some embodiments, the detergent may contain trace amounts of other metals, such as magnesium or calcium, in amounts such as 50 ppm or less, 40 ppm or less, 30 ppm or less, 20 ppm or less, or 10 ppm or less. Suitable detergents can include alkali metal or alkaline earth metal salts of petroleum sulfonic acids and long-chain mono- or di-alkylaryl sulfonic acids, where the aryl group is benzyl, tolyl, and xylyl. Examples of suitable detergents include, but are not limited to: calcium phenate, sulfurized calcium phenate, calcium sulfonate, calcium calixarates, calcium salixarates, calcium salicylate, calcium carboxylate, calcium phosphate, calcium monothiophosphate and / or calcium dithiophosphate, alkyl calcium phenate, sulfur-coupled alkyl calcium phenate compounds, methylene-bridged calcium phenate, magnesium phenate, sulfurized magnesium phenate, magnesium sulfonate, magnesium calixarates, magnesium salixarates, magnesium salicylate, magnesium carboxylate, magnesium phosphate, magnesium monothiophosphate and / or magnesium dithiophosphate, alkyl magnesium phenate, sulfur-coupled alkyl magnesium phenate compounds, methylene-bridged magnesium phenate, sodium phenate, sulfurized sodium phenate, sodium sulfonate, sodium calixarates, sodium salixarates, sodium salicylate, sodium carboxylate, sodium phosphate, sodium monothiophosphate and / or sodium dithiophosphate, alkyl sodium phenate, sulfur-coupled alkyl sodium phenate compounds, or methylene-bridged sodium phenate.

[0097] Overbased detergent additives are well known in the art and can be alkali metal or alkaline earth metal overbased detergent additives. Such detergent additives can be prepared by reacting a metal oxide or metal hydroxide with a base and carbon dioxide gas. The base is typically an acid, such as the following acids: sulfonic acids substituted with aliphatics, carboxylic acids substituted with aliphatics, or phenols substituted with aliphatics.

[0098] The term "overbased" refers to metal salts, such as metal salts of sulfonic acids, carboxylic acids, and phenols, where the amount of metal present exceeds the stoichiometric amount. Such salts can have a conversion level of more than 100% (i.e., they can contain more than 100% of the theoretical amount of metal required to convert the acid to its "normal" salt, "neutral" salt). The expression "metal ratio" is usually abbreviated as MR, and this expression is used to represent the ratio of the total chemical equivalent of the metal in the overbased salt to the chemical equivalent of the metal in the neutral salt, based on known chemical reactivity and stoichiometry. In a normal salt or neutral salt, the metal ratio is one, while in an overbased salt, the MR is greater than one. They are commonly referred to as overbased, superbased, or hyperbased salts, and can be salts of organic sulfuric acids, carboxylic acids, or phenols.

[0099] The total base number (TBN) of the overbased detergent of the lubricating oil composition can be about 200 mg KOH / gram or greater, or in other examples, about 250 mg KOH / gram or greater, or about 350 mg KOH / gram or greater, or about 375 mg KOH / gram or greater, or about 400 mg KOH / gram or greater. The TBN is measured by the method of ASTM D-2896.

[0100] Examples of suitable overbased detergents include, but are not limited to: overbased calcium phenate, overbased sulfur-containing calcium phenate, overbased calcium sulfonate, overbased calixarboxylate calcium, overbased salicylate calcium, overbased calcium carboxylate, overbased calcium phosphate, overbased calcium monothiophosphate and / or dithiophosphate, overbased calcium alkylphenate, overbased sulfur-coupled calcium alkylphenate compound, overbased methylene-bridged calcium phenate, overbased magnesium phenate, overbased sulfur-containing magnesium phenate, overbased magnesium sulfonate, overbased calixarboxylate magnesium, overbased salicylate magnesium, overbased magnesium carboxylate, overbased magnesium phosphate, overbased magnesium monothiophosphate and / or dithiophosphate, overbased magnesium alkylphenate, overbased sulfur-coupled magnesium alkylphenate compound or overbased methylene-bridged magnesium phenate.

[0101] The total base number of the overbased calcium phenate detergent is at least about 150 mg KOH / g, at least about 225 mg KOH / g, at least about 225 mg KOH / g to about 400 mg KOH / g, at least about 225 mg KOH / g to about 350 mg KOH / g or about 230 mg KOH / to about 350 mg KOH / g, all as measured by the method of ASTM D-2896. When such a detergent composition is formed in an inert diluent (such as process oil, typically mineral oil), the total base number reflects the alkalinity of the overall composition, which composition includes the diluent and any other materials (such as promoters, etc.) that the detergent composition may contain.

[0102] The ratio of metal to substrate of the overbased detergent can be 1.1:1, or 2:1, or 4:1, or 5:1, or 7:1, or 10:1. In some embodiments, the detergent is effective in reducing or preventing rust in an engine or other automotive components (such as a transmission or gears). The detergent can be present in the lubricating composition at about 0 wt% to about 10 wt%, or about 0.1 wt% to about 8 wt%, or about 1 wt% to about 4 wt%, or greater than about 4 wt% to about 8 wt%.

[0103] Extreme pressure agent: The lubricating oil composition herein may also optionally contain one or more extreme pressure agents. Extreme pressure (EP) agents soluble in oil include sulfur- and chlorosulfur-containing EP agents, chlorinated hydrocarbon EP agents, and phosphorus EP agents. Examples of such EP agents include chlorinated waxes; organic sulfides and polysulfides such as bis(dibenzyl) disulfide, bis(chlorobenzyl) disulfide, dibutyl tetrasulfide, methyl oleate sulfide, alkylphenol sulfide, dipentene sulfide, terpene sulfide, Diels-Alder adduct sulfide; phosphorus-sulfurized hydrocarbons such as the reaction product of sulfurized phosphorus with turpentine or methyl oleate; phosphites such as dialkyl phosphites and trialkyl phosphites, e.g., dibutyl phosphite, diheptyl phosphite, dicyclohexyl phosphite, amylphenyl phosphite; dipentyl phenyl phosphite, tridecyl phosphite, distearyl phosphite, and polypropylene-substituted phenyl phosphite; metal thiocarbamates such as zinc dioctyl dithiocarbamate and barium heptylphenol dithiocarbamate; amine salts of alkyl and dialkyl phosphoric acids, including for example the amine salts of the reaction product of dialkyl dithiophosphoric acid and propylene oxide; and mixtures thereof.

[0104] Friction modifier : The lubricating oil composition herein may also optionally contain one or more friction modifiers. Suitable friction modifiers may include metal-containing and metal-free friction modifiers, and may include but are not limited to imidazolines, amides, amines, succinimides, alkoxylated amines, alkoxylated ether amines, amine oxides, amidomines, nitriles, betaines, quaternary amines, imines, amine salts, aminoguanidines, alkanolamides, phosphonates, metal-containing compounds, glycerol esters, sulfurized fatty compounds and olefins, sunflower oil, other naturally occurring plant or animal oils, dicarboxylic esters, esters or partial esters of polyols, and one or more aliphatic or aromatic carboxylic acids, etc.

[0105] Suitable friction modifiers may contain a hydrocarbon group selected from linear, branched, or aromatic hydrocarbon groups or mixtures thereof, and may be saturated or unsaturated. The hydrocarbon group may consist of carbon and hydrogen or heteroatoms such as sulfur or oxygen. The hydrocarbon group may range from about 12 to about 25 carbon atoms. In some embodiments, the friction modifier may be a long-chain fatty acid ester. In another embodiment, the long-chain fatty acid ester may be a monoester or diester or (tri)glycerol ester. The friction modifier may be a long-chain fatty amide, long-chain fatty ester, long-chain fatty epoxide derivative, or long-chain imidazoline.

[0106] Other suitable friction modifiers can include organic, ashless (metal-free), nitrogen-free organic friction modifiers. Such friction modifiers can include esters formed by reacting carboxylic acids and anhydrides with alkanols and generally contain polar end groups (e.g., carboxyl or hydroxyl groups) covalently bonded to lipophilic hydrocarbon chains. Examples of organic ashless nitrogen-free friction modifiers are generally known as glycerol monooleate (GMO), which can contain mono-, di-, and triesters of oleic acid. Other suitable friction modifiers are described in U.S. Patent No. 6,723,685, which is incorporated herein by reference in its entirety.

[0107] Amine friction modifiers can include amines or polyamines. Such compounds can have linear chains, saturated or unsaturated hydrocarbon groups, or mixtures thereof, and can contain from about 12 to about 25 carbon atoms. Other examples of suitable friction modifiers include alkoxylated amines and alkoxylated ether amines. Such compounds can have linear chains, saturated or unsaturated hydrocarbon groups, or mixtures thereof. They can contain from about 12 to about 25 carbon atoms. Examples include ethoxylated amines and ethoxylated ether amines.

[0108] Amines and amides can be used as such or in the form of an adduct or reaction product with a boron compound (such as boron oxide, boron halide, metaborate ester, boric acid, or monoalkyl, dialkyl, or trialkyl borate). Other suitable friction modifiers are described in U.S. Patent No. 6,300,291, which is incorporated herein by reference in its entirety.

[0109] The friction modifier can optionally be present in ranges such as from about 0 wt% to about 10 wt%, or from about 0.01 wt% to about 8 wt%, or from about 0.1 wt% to about 4 wt%.

[0110] Molybdenum-containing component : The lubricating oil compositions herein can also optionally contain one or more molybdenum-containing compounds. Oil-soluble molybdenum compounds can have the functional properties of an antiwear agent, antioxidant, friction modifier, or mixtures thereof. Oil-soluble molybdenum compounds can include molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, molybdenum dithiophosphite, amine salts of molybdenum compounds, molybdenum xanthate, molybdenum thioxanthate, molybdenum sulfide, molybdenum carboxylate, molybdenum alkanol, trinuclear organomolybdenum compounds, and / or mixtures thereof. Molybdenum sulfide includes molybdenum disulfide. Molybdenum disulfide can be in the form of a stable dispersion. In one embodiment, the oil-soluble molybdenum compound can be selected from the group consisting of molybdenum dithiocarbamate, molybdenum dialkyldithiophosphate, amine salts of molybdenum compounds, and mixtures thereof. In one embodiment, the oil-soluble molybdenum compound can be molybdenum dithiocarbamate.

[0111] Suitable examples of molybdenum compounds that can be used include commercial substances sold under the following trade names: Molyvan 822 from R.T. Vanderbilt Co., Ltd. TM , Molyvan TM A, Molyvan 2000 TM and Molyvan 855 TM and Sakura-Lube available from Adeka Corporation TM S-165, S-200, S-300, S-310G, S-525, S-600, S-700 and S-710, and mixtures thereof. Suitable molybdenum components are described in US5,650,381; US RE 37,363 E1; US RE 38,929 E1; and US RE 40,595 E1, the entire texts of which are incorporated herein by reference.

[0112] Additionally, the molybdenum compound can be an acidic molybdenum compound. These include molybdic acid, ammonium molybdate, sodium molybdate, potassium molybdate and other molybdenum alkali metal salts and other molybdenum salts, such as sodium hydrogen molybdate, MoOCl4, MoO2Br2, Mo2O3Cl6, molybdenum trioxide or similar acidic molybdenum compounds. Alternatively, these compositions can provide molybdenum through molybdenum / sulfur complexes of basic nitrogen compounds, as described, for example, in U.S. Patent Nos. 4,263,152; 4,285,822; 4,283,295; 4,272,387; 4,265,773; 4,261,843; 4,259,195 and 4,259,194; and WO 94 / 06897, the entire texts of which are incorporated herein by reference.

[0113] Another class of suitable organomolybdenum compounds are trinuclear molybdenum compounds, such as those having the formula Mo3SkLnQz and mixtures thereof, where S represents sulfur, L represents a ligand independently selected having an organic group having a number of carbon atoms sufficient to confer solubility or dispersibility of the compound in oil, n is from 1 to 4, k varies in the range from 4 to 7, Q is selected from the group of neutral electron donor compounds such as water, amines, alcohols, phosphines and ethers, and z is in the range from 0 to 5 and includes non-stoichiometric values. A total of at least 21 carbon atoms may be present in the organic groups of all ligands, such as at least 25, at least 30 or at least 35 carbon atoms. Additional suitable molybdenum compounds are described in U.S. Patent No. 6,723,685, the entire text of which is incorporated herein by reference.

[0114] The oil-soluble molybdenum compound may be present in an amount sufficient to provide from about 0.5 ppm to about 2000 ppm, from about 1 ppm to about 700 ppm, from about 1 ppm to about 550 ppm, from about 5 ppm to about 300 ppm, or from about 20 ppm to about 250 ppm of molybdenum.

[0115] Compound containing transition metal : In another embodiment, the oil-soluble compound can be a transition metal-containing compound or a metalloid. Transition metals can include, but are not limited to: titanium, vanadium, copper, zinc, zirconium, molybdenum, tantalum, tungsten, etc. Suitable metalloids include, but are not limited to: boron, silicon, antimony, tellurium, etc.

[0116] In one embodiment, the oil-soluble transition metal-containing compound can function as an antiwear agent, a friction modifier, an antioxidant, a deposit control additive, or more than one of these functions. In one embodiment, the oil-soluble transition metal-containing compound can be an oil-soluble titanium compound, such as titanium(IV) alkoxide. There are various Ti(IV) compounds among the titanium-containing compounds that can be used in the disclosed technology or can be used to prepare the oil-soluble materials of the disclosed technology, such as titanium(IV) oxide; titanium(IV) sulfide; titanium(IV) nitrate; titanium(IV) alkoxides, such as titanium methoxide, titanium ethoxide, titanium propoxide, titanium isopropoxide, titanium butoxide, titanium 2-ethylhexoxide; and other titanium compounds or complexes, including but not limited to titanium phenoxide; titanium carboxylates, such as titanium(IV) 2-ethyl-1,3-hexanedioate or titanium citrate or titanium oleate; and titanium(IV) (triethanolamine) isopropoxide. Other forms of titanium covered by the disclosed technology include titanium phosphates, such as titanium dithiophosphate (e.g., dialkyldithiophosphate titanium), and titanium sulfonates (e.g., alkylbenzenesulfonate titanium), or generally, the reaction products of titanium compounds reacting with various acidic materials to form salts (such as oil-soluble salts). Titanium compounds can thus be derived especially from organic acids, alcohols, and diols. Ti compounds can also exist in dimeric or oligomeric forms, containing a Ti--O--Ti structure. Such titanium materials are commercially available or can be easily prepared by appropriate synthetic techniques obvious to those skilled in the art. They exist in solid or liquid form at room temperature, depending on the specific compound. They can also be provided in the form of solutions in suitable inert solvents.

[0117] In one embodiment, titanium may be supplied as a Ti-modified dispersant, such as a succinimide dispersant. Such materials can be prepared by forming a titanium mixed anhydride between a titanium alkoxide and a hydrocarbyl-substituted succinic anhydride, such as an alkenyl (or alkyl) succinic anhydride. The resulting titanate-succinate intermediate can be used directly, or it can be reacted with any of a number of materials, such as (a) a polyamine-based succinimide / amide dispersant having a free, condensable --NH functional group; (b) the components of a polyamine-based succinimide / amide dispersant, namely an alkenyl (or alkyl) succinic anhydride and a polyamine, (c) a hydroxy-containing polyester dispersant prepared by reacting a substituted succinic anhydride with a polyol, an amino alcohol, a polyamine, or a mixture thereof. Alternatively, the titanate-succinate intermediate can be reacted with other reagents, such as an alcohol, an amino alcohol, an ether alcohol, a polyether alcohol, or a polyol or a fatty acid, and the product can be used directly to impart Ti to a lubricant, or alternatively, it can be reacted further with a succinic acid dispersant as described herein. As an example, 1 part (molar) of titanium tetraisopropoxide can be reacted with about 2 parts (molar) of polyisobutylene-substituted succinic anhydride at 140 °C to 150 °C for 5 to 6 hours to provide a Ti-modified dispersant or intermediate. The resulting material (30 g) can also be reacted with a succinimide dispersant and a mixture of polyethylene polyamines (127 g + diluent oil) from polyisobutylene-substituted succinic anhydride at 150 °C for 1.5 hours to produce a Ti-modified succinimide dispersant.

[0118] Another titanium-containing compound can be the reaction product of a titanium alkoxide and a C6 to C 25 carboxylic acid. The reaction product can be represented by the formula:

[0119]

[0120] wherein n is an integer selected from 2, 3, and 4, and R is a hydrocarbyl group containing from about 5 to about 24 carbon atoms, or is represented by the formula:

[0121]

[0122] wherein m + n = 4 and n ranges from 1 to 3, R4 is an alkyl moiety having from 1 to 8 carbon atoms, R1 is selected from hydrocarbyl groups containing from about 6 to 25 carbon atoms, and R2 and R3 are the same or different and are selected from hydrocarbyl groups containing from about 1 to 6 carbon atoms, or the titanium compound can be represented by the formula:

[0123]

[0124] wherein x ranges from 0 to 3, R1 is selected from hydrocarbyl groups containing from about 6 to 25 carbon atoms, R2 and R3 are the same or different and are selected from hydrocarbyl groups containing from about 1 to 6 carbon atoms, and R4 is selected from the group consisting of H, or a C6 to C 25 carboxylic acid moiety.

[0125] Suitable carboxylic acids can include, but are not limited to, caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, oleic acid, erucic acid, linoleic acid, linolenic acid, cyclohexanecarboxylic acid, phenylacetic acid, benzoic acid, neodecanoic acid, etc.

[0126] In one embodiment, the oil-soluble titanium compound can be present in the lubricating oil composition in an amount of 0 ppm to 3000 ppm titanium by weight, or 25 ppm to about 1500 ppm titanium by weight, or about 35 ppm to 500 ppm titanium by weight, or about 50 ppm to about 300 ppm.

[0127] Viscosity index improver : The lubricating oil compositions herein may also optionally contain one or more viscosity index improvers. Suitable viscosity index improvers can include polyolefins, olefin copolymers, ethylene / propylene copolymers, polyisobutylene, hydrogenated styrene-isoprene polymers, styrene / maleate copolymers, hydrogenated styrene / butadiene copolymers, hydrogenated isoprene polymers, α-olefin maleic anhydride copolymers, polymethacrylates, polyacrylates, polyalkylstyrenes, hydrogenated vinyl aromatic conjugated diene copolymers, or mixtures thereof. Viscosity index improvers can include star polymers, and suitable examples are described in U.S. Publication No. 20120101017A1.

[0128] The lubricating oil compositions herein may also optionally contain one or more dispersant viscosity index improvers in addition to or in place of the viscosity index improvers. Suitable viscosity index improvers can include functionalized polyolefins, such as ethylene-propylene copolymers that have been functionalized with the reaction product of an acylating agent (such as maleic anhydride) and an amine; polymethacrylates functionalized with an amine, or esterified maleic anhydride-styrene copolymers reacted with an amine.

[0129] The total amount of the viscosity index improver and / or the dispersant viscosity index improver can be about 0 wt% to about 20 wt%, about 0.1 wt% to about 15 wt%, about 0.1 wt% to about 12 wt%, or about 0.5 wt% to about 10 wt% of the lubricating oil composition.

[0130] Other optional additives : Other additives can be selected to perform one or more functions required of the lubricating fluid. Additionally, one or more of the additives mentioned can be multifunctional and provide functions other than or different from the functions specified herein.

[0131] The lubricating oil composition according to the present disclosure may optionally contain other performance additives. The other performance additives may be additives other than the specified additives of the present disclosure and / or may include one or more of the following: metal deactivators, viscosity index improvers, detergents, ashless TBN boosters, friction modifiers, antiwear agents, corrosion inhibitors, rust inhibitors, dispersants, dispersant viscosity index improvers, extreme pressure agents, antioxidants, foam inhibitors, demulsifiers, emulsifiers, pour point depressants, seal swell agents, and mixtures thereof. Generally, the full formulated lubricating oil will contain one or more of these performance additives.

[0132] Suitable metal deactivators may include derivatives of benzotriazole (usually tolyltriazole), dimercaptothiadiazole derivatives, 1,2,4-triazole, benzimidazole, 2-alkyldithiobenzimidazole or 2-alkyldithiobenzothiazole; foam inhibitors, including copolymers of ethyl acrylate and 2-ethylhexyl acrylate and optionally vinyl acetate; demulsifiers, including trialkyl phosphates, polyethylene glycols, polyethylene oxides, polypropylene oxides, and (ethylene oxide - propylene oxide) polymers; pour point depressants, including esters of maleic anhydride - styrene, polymethacrylates, polyacrylates, or polyacrylamides.

[0133] Suitable foam inhibitors include silicon-based compounds such as siloxanes.

[0134] Suitable pour point depressants may include polymethyl methacrylate or mixtures thereof. The pour point depressant may be present in an amount sufficient to provide from about 0 wt% to about 1 wt%, about 0.01 wt% to about 0.5 wt%, or about 0.02 wt% to about 0.04 wt% based on the final weight of the lubricating oil composition.

[0135] Suitable rust inhibitors may be a single compound or a mixture of compounds having the property of inhibiting corrosion on the surface of ferrous metals. Non-limiting examples of rust inhibitors useful herein include: oil-soluble high molecular weight organic acids such as 2-ethylhexanoic acid, lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, behenic acid, and cerotic acid; and oil-soluble polycarboxylic acids including dimer acids and trimer acids such as those produced from tall oil fatty acids, oleic acid, and linoleic acid. Other suitable corrosion inhibitors include long-chain α,ω-dicarboxylic acids having a molecular weight in the range of about 600 to about 3000, and alkenyl succinic acids in which the alkenyl group contains about 10 or more carbon atoms such as tetrapropenyl succinic acid, tetradecenyl succinic acid, and hexadecenyl succinic acid. Another type of acidic corrosion inhibitor useful is a half-ester of an alkenyl succinic acid having about 8 to about 24 carbon atoms in the alkenyl group with an alcohol such as polyethylene glycol. The corresponding half-amides of such alkenyl succinic acids are also useful. Useful rust inhibitors are high molecular weight organic acids.

[0136] If present, the rust inhibitor is used in an amount sufficient to provide about 0 wt% to about 5 wt%, about 0.01 wt% to about 3 wt%, or about 0.1 wt% to about 2 wt% based on the final weight of the lubricating oil composition.

[0137] Generally, suitable lubricants including the neutral to overbased and sulfided alkylphenate products herein may include additive components within the ranges listed in the table below.

[0138] Table 2: Suitable lubricating compositions

[0139]

[0140] Based on the weight of the final lubricating oil composition, the percentage (%) by weight of each component above represents the weight percentage of each component. The remainder of the lubricating oil composition consists of one or more base oils. The additives used to formulate the compositions described herein may be blended into the base oil individually or in various sub-combinations. However, it may be suitable to use an additive concentrate (i.e., an additive plus a diluent such as a hydrocarbon solvent) to blend all components simultaneously. A fully formulated lubricant typically contains an additive package, referred to herein as a dispersant / inhibitor package or DI package, which will supply the desired characteristics in the formulation.

[0141] The following term definitions are provided to clarify the meaning of certain terms as used herein.

[0142] The terms "oil composition", "lubricating composition", "lubricating oil composition", "lubricating oil", "lubricant composition", "fully formulated lubricant composition", and "lubricant" are considered synonymous and fully interchangeable terms and refer to a finished lubricating product that contains a major amount of base oil plus a minor amount of additive composition.

[0143] As used herein, the terms "additive package", "additive concentrate", and "additive composition" are considered synonymous and fully interchangeable terms and refer to the portion of a lubricating oil composition that does not include a major amount of base oil feedstock mixture.

[0144] The term "overbased" relates to metal salts such as sulfonates, carboxylates, salicylates and / or phenates, where the metal content exceeds the stoichiometric amount. Such salts can have a conversion level of over 100% (i.e., they can contain more than 100% of the theoretical amount of metal required to convert the acid to its "normal", "neutral" salt). The expression "metal ratio", usually abbreviated as MR, is used to denote the ratio of the total chemical equivalents of metal in the overbased salt to the chemical equivalents of metal in the neutral salt, based on known chemical reactivity and stoichiometry. In a normal or neutral salt, the metal ratio is one, while in an overbased salt, the MR is greater than one. They are commonly referred to as overbased, superbased or hyperbased salts and can be salts of organic sulfuric acids, carboxylic acids, salicylic acids, sulfonic acids and / or phenols.

[0145] The term "alkaline earth metal" relates to calcium, barium, magnesium and strontium, and the term "alkali metal" refers to lithium, sodium, potassium, rubidium and cesium.

[0146] As used herein, the term "hydrocarbyl" or "hydrocarbyl substituent" or "hydrocarbyl group" is used in its ordinary sense, which is well known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly connected to the remainder of the molecule and predominantly having hydrocarbon character. Each hydrocarbyl group is independently selected from hydrocarbon substituents and substituted hydrocarbon substituents containing one or more of a halogen group, a hydroxy group, an alkoxy group, a mercapto group, a nitro group, a nitroso group, an amino group, a pyridyl group, a furyl group, an imidazolyl group, oxygen and nitrogen, and where there are no more than two non-hydrocarbon substituents per ten carbon atoms in the hydrocarbyl group.

[0147] As used herein, the term "subhydrocarbyl substituent" or "subhydrocarbyl group" is used in its usual meaning, which is well known to those skilled in the art. Specifically, it refers to a group that is directly attached to the remainder of the molecule at two positions in the molecule through carbon atoms and predominantly has hydrocarbon character. Each subhydrocarbyl group is independently selected from divalent hydrocarbon substituents and substituted divalent hydrocarbon substituents containing: a halogen group, an alkyl group, an aryl group, an alkaryl group, an aralkyl group, a hydroxy group, an alkoxy group, a mercapto group, a nitro group, a nitroso group, an amino group, a pyridyl group, a furyl group, an imidazolyl group, oxygen and nitrogen, and where there are no more than two non-hydrocarbon substituents per ten carbon atoms in the subhydrocarbyl group.

[0148] Unless otherwise expressly stated, as used herein, the term "weight %" refers to the percentage by weight of the component in the total weight of the composition.

[0149] As used herein, the terms "soluble", "oil-soluble", or "dispersible" may but do not necessarily mean that a compound or additive is soluble, dissolvable, miscible, or capable of being suspended in oil in all proportions. However, the foregoing terms do mean that they are, for example, soluble, suspendable, dissolvable, or stably dispersible in oil to an extent sufficient to perform their intended function in an environment employing oil. Additionally, if desired, the incorporation of other additives may also permit the incorporation of higher levels of a particular additive.

[0150] As used herein, the term "TBN" is used to denote the total base number in mg KOH / g as measured by the method of ASTM D2896.

[0151] As used herein, the term "lime" refers to compounds such as calcium hydroxide, calcium oxide, etc., also known as slaked lime or hydrated lime.

[0152] As used herein, the term "alkyl" refers to a straight-chain, branched-chain, cyclic, and / or substituted saturated chain moiety having from about 1 to about 100 carbon atoms. As used herein, the term "alkenyl" refers to a straight-chain, branched-chain, cyclic, and / or substituted unsaturated chain moiety having from about 3 to about 10 carbon atoms. As used herein, the term "aryl" refers to monocyclic and polycyclic aromatic compounds, which may include alkyl, alkenyl, alkaryl, amino, hydroxy, alkoxy, halogen substituents, and / or heteroatoms including, but not limited to, nitrogen, oxygen, and sulfur.

[0153] The molecular weight of any embodiment herein can be measured using an instrument such as a gel permeation chromatography (GPC) instrument obtained from Waters, and the data can be processed using software such as Waters Empower software. The GPC instrument can be equipped with a Waters separation module and a Waters refractive index detector (or similar optional equipment). The GPC operating conditions can include a guard column, 4 Agilent PLgel columns (length 300×7.5 mm; particle size is 5 μ, and the pore size range is ) The column temperature is about 40 °C. Unstabilized HPLC grade tetrahydrofuran (THF) can be used as the solvent, and the flow rate is 1.0 mL / min. The GPC instrument can be calibrated with commercially available polystyrene (PS) standards having a narrow molecular weight distribution ranging from 500 g / mol to 380,000 g / mol. For samples with a mass less than 500 g / mol, the calibration curve can be extrapolated. The samples and PS standards can be dissolved in THF and prepared at a concentration of 0.1 wt% to 0.5 wt%, and used without filtration. GPC measurements are also described in US 5,266,223, which is incorporated herein by reference. The GPC method additionally provides molecular weight distribution information; see, e.g., W.W. Yau, J.J. Kirkland, and D.D. Bly, "Modern Size Exclusion Liquid Chromatography", John Wiley and Sons, New York, 1979, which is also incorporated herein by reference.

[0154] Example

[0155] The following examples are illustrative of exemplary embodiments of the present disclosure. In these examples, as well as elsewhere in this application, all ratios, parts, and percentages are by weight unless otherwise indicated. These examples are presented for illustrative purposes only and are not intended to limit the scope of the invention disclosed herein.

[0156] Example 1

[0157] A comparative (e.g., conventional) overbased magnesium sulfonate detergent is prepared by overbasing a C14 to C24 alkylbenzene sulfonic acid with xylene, methanol as a promoter, a molar excess of magnesium oxide, carbon dioxide as an overbasing acid, and neodecanoic acid at a temperature of about 50 to about 70 °C. The mixture is vacuum stripped at about 180 °C to form a comparative overbased magnesium sulfonate detergent having a TBN of about 450 mg KOH / gram, about 9.5 wt% to about 10.5 wt% magnesium, and a KV100 viscosity of about 9 cSt to about 10 cSt. Unreacted solids are removed by filtration and / or centrifugation. The conventional or comparative detergent undergoes no further post-treatment after vacuum stripping.

[0158] Example 2

[0159] Then, the conventional overbased magnesium sulfonate detergent of Example 1 was further post-treated at about 180 °C with polyisobutylene succinic anhydride (PIBSA), wherein different polyisobutenes with number average molecular weights of about 550 g / mol, about 850 g / mol, about 950 g / mol, about 1000 g / mol or about 2400 g / mol were used. The polyisobutene in each case was considered to be HR-PIB having at least about 50 mol% terminal double bonds. The post-treated overbased magnesium sulfonate detergents were prepared by treating the comparative overbased magnesium sulfonate detergent of Example 1 at 180 °C with each of the post-treatment reactants in Table 2 below for about 15 minutes to about 60 minutes.

[0160] Table 2

[0161] Sample PIBSA, Mn Treatment rate of PIBSA during post-treatment, wt% 1 2400 5％ 2 2400 10％ 3 950 2％ 4 950 8％ 5 950 10％ 6 1000 10％ 7 850 10％ 8 550 10％

[0162] The storage stability of a lubricating oil composition containing overbased magnesium sulfonate and 0.4 wt% glycerol monooleate was evaluated at about 55 °C. For this study, the control (C) included the comparative or conventional overbased magnesium sulfonate of Example 1, followed by the post-treated overbased magnesium sulfonate detergents 1 to 8 of Example 2 from the same GF-6 lubricant (Table 2).

[0163] To test the storage stability, more than 20 grams to about 25 grams of each lubricant were added to clear glass vials. Each vial was stored at about 55 °C, and the stability was evaluated once a week (after about 168 hours) for up to 28 weeks. As shown in Table 3 below, passed stability was indicated by "P", and failed stability was indicated by "F". Passing means the lubricant was free of precipitation, dropout, and film formation. A failed sample meant that any deposits (solid particles) or film were present at the bottom of the vial upon visual inspection at the appropriate time (weeks) using backlighting.

[0164] Table 3: Stability chart

[0165]

[0166] As shown in the stability graph of Example 3, control sample C of conventional over-alkaline magnesium sulfonate and glycerol monooleate (i.e., untreated) lost stability only after 4 weeks. As shown in comparative sample 8, post-treatment with PIBSA of 550 molecular weight improved stability, but only by 1 week. Post-treatment with PIBSA of higher molecular weights of 850 or even 2400 improved stability, but only up to 17 weeks (i.e., comparative samples 1 to 2 and 7). Samples 4, 5, and 6 of the present invention post-treated with about 8 wt% to about 10 wt% of PIBSA of about 950 g / mol to about 1000 g / mol unexpectedly improved storage stability, up to at least 18 weeks (sample 4 of the present invention using about 8 wt% of about 950 Mn PIBSA), up to 27 weeks (sample 5 of the present invention using about 10 wt% of about 950 Mn PIBSA), and up to 26 weeks (sample 6 of the present invention using about 10 wt% of about 1000 Mn PIBSA).

[0167] It should be noted that, unless expressly and affirmatively limited to one indicator, as used in this specification and the appended claims, the singular forms "a / an" and "the" include plural indicators. Thus, for example, reference to "an antioxidant" includes two or more different antioxidants. The term "comprising" as used herein and its grammatical variants are intended to be non-limiting, such that the recitation of items in a list does not preclude other similar items that may be substituted or added to the listed items.

[0168] For this specification and the appended claims, unless otherwise indicated, all numbers and other numerical values representing quantities, percentages, or proportions used in the specification and claims shall be understood to be modified in all instances by the term "about". Thus, unless indicated to the contrary, the numerical parameters set forth in the following specification and appended claims are approximations that may vary depending upon the desired properties sought to be obtained by this disclosure. At the very least, and without attempting to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0169] It should be understood that each component, compound, substituent, or parameter disclosed herein is to be construed as being disclosed for use alone or in combination with one or more of each of the other components, compounds, substituents, or parameters disclosed herein.

[0170] It should be further understood that each range disclosed herein is to be construed as an express disclosure of every specific value falling within the disclosed range having the same numerical value of significant digits. Thus, for example, a range of 1 to 4 is to be construed as an express disclosure of the values 1, 2, 3, and 4 and any range of such values.

[0171] It should be further understood that each lower limit of each scope disclosed herein should be interpreted as being disclosed in combination with each upper limit of each scope disclosed herein for the same component, compound, substituent or parameter and each specific value in each scope. Therefore, the disclosure should be interpreted as being disclosed by combining each lower limit of each scope with each upper limit of each scope or with each specific value in each scope, or by combining each upper limit of each scope with each specific value in each scope. That is, it should also be further understood that any scope between the endpoint values in a wide range is also discussed herein. Therefore, the scope of 1 to 4 also means the scope of 1 to 3, 1 to 2, 2 to 4, 2 to 3, etc.

[0172] In addition, a specific amount / value of a component, compound, substituent or parameter disclosed in this specification or the examples should be interpreted as a disclosure of a lower or upper limit of a range, and therefore can be combined with any other lower or upper limit or specific amount / value of a range for the same component, compound, substituent or parameter disclosed elsewhere in this disclosure to form a range for that component, compound, substituent or parameter.

[0173] Although specific embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are not currently foreseen or may not currently be foreseen may occur to applicants or other persons skilled in the art. Therefore, the appended claims as filed and as they may be amended are intended to cover all such alternatives, modifications, variations, improvements, and substantial equivalents.

Claims

1. A method for preparing an overbased magnesium sulfonate detergent having improved compatibility with a friction modifier, the method comprising: (a) preparing a mixture of a C14 to C24 alkylaryl sulfonic acid or its salt, magnesium oxide or magnesium hydroxide, and one or more branched C8 to C16 carboxylic acids; (b) carbonating the mixture to form an overbased magnesium sulfonate; (c) treating the carbonated overbased magnesium sulfonate at about 160°C to about 200°C with about 6 wt% to about 10 wt% of a hydrocarbyl-substituted succinic acid or anhydride to form the overbased magnesium sulfonate detergent, wherein the hydrocarbyl substituent of the hydrocarbyl-substituted succinic acid or anhydride has a number average molecular weight of about 900 to about 1500 and is derived from a polyisobutene having greater than 50 mol% terminal double bonds; and wherein the overbased magnesium sulfonate detergent has improved compatibility with a friction modifier.

2. The method according to claim 1, wherein the overbased magnesium sulfonate has a total base number (TBN) of at least about 450 mg KOH / g before the treatment, and the overbased magnesium sulfonate detergent has a total base number (TBN) of less than about 410 mg KOH / g after the treatment; and / or wherein the treatment step (c) is substantially free of dicarboxylic acids, and wherein the dicarboxylic acids are one or more of the following: phthalic acid, succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, malonic acid, or combinations thereof.

3. The method according to claim 2, wherein the overbased magnesium sulfonate detergent contains at least about 60 wt% of magnesium sulfonate as an active ingredient; and / or wherein the overbased magnesium sulfonate detergent has about 35 wt% or less of processing oil.

4. The method according to claim 1, wherein before the treatment step (c), the overbased magnesium sulfonate is vacuum stripped at about 160°C to about 200°C; and / or wherein the overbased magnesium sulfonate detergent is storage stable at about 55°C for at least about 18 weeks when combined with up to about 0.4 wt% of glyceryl monooleate.

5. A storage-stable overbased magnesium sulfonate detergent having improved compatibility with a friction modifier, the storage-stable overbased magnesium sulfonate detergent being made by a method comprising: (a) preparing a mixture of a straight-chain C14 to C24 alkylaryl sulfonic acid or its salt, magnesium oxide or magnesium hydroxide, and one or more branched C8 to C16 carboxylic acids; (b) carbonating the mixture to form an overbased magnesium sulfonate; (c) treating the carbonated overbased magnesium sulfonate at about 160°C to about 200°C with about 6 wt% to about 10 wt% of a hydrocarbyl-substituted succinic acid or anhydride to form the overbased magnesium sulfonate detergent, wherein the hydrocarbyl substituent of the hydrocarbyl-substituted succinic acid or anhydride has a number average molecular weight of about 900 to about 1500 and is derived from a polyisobutene having greater than 50 mol% terminal double bonds; and wherein the overbased magnesium sulfonate detergent has improved compatibility with a friction modifier.

6. The storage-stable overbased magnesium sulfonate detergent according to claim 5, wherein the overbased magnesium sulfonate has a total base number (TBN) of at least about 450 mg KOH / g before the treatment, and the overbased magnesium sulfonate detergent has a total base number (TBN) of less than about 410 mg KOH / g after the treatment; and / or wherein the treatment step (c) is substantially free of dicarboxylic acids, and wherein the dicarboxylic acid is one or more of the following: phthalic acid, succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, malonic acid, or a combination thereof.

7. The storage-stable overbased magnesium sulfonate detergent according to claim 5, wherein the overbased magnesium sulfonate detergent comprises at least about 60% by weight of magnesium sulfonate as an active ingredient; and / or wherein the overbased magnesium sulfonate detergent has about 35% by weight or less of processing oil.

8. The storage-stable overbased magnesium sulfonate detergent according to claim 5, wherein before the treatment step (c), the overbased magnesium sulfonate is vacuum stripped at about 160 °C to about 200 °C; and / or wherein the overbased magnesium sulfonate detergent has a total base number (TBN) of about 350 mg KOH / g to about 410 mg KOH / g and is storage-stable at about 55 °C for at least about 18 weeks when combined with up to about 0.4% by weight of a glycerol monooleate friction modifier.

9. An engine oil lubricating composition, the engine oil lubricating composition comprising: a major amount of one or more base oils having lubricating viscosity, the storage-stable overbased magnesium sulfonate detergent according to claim 5, and up to about 0.4% by weight of a glycerol monooleate friction modifier.

10. A method for improving the storage stability of an overbased magnesium sulfonate detergent, the method comprising: (a) preparing a mixture of a linear C14 to C24 alkylaryl sulfonic acid or its salt, magnesium oxide or magnesium hydroxide, and one or more branched C8 to C16 carboxylic acids; carbonating the mixture to form an overbased magnesium sulfonate; treating the formed overbased magnesium sulfonate with about 6% to about 10% by weight of a hydrocarbyl-substituted succinic anhydride at about 160 °C to about 200 °C to form the overbased magnesium sulfonate detergent, wherein the hydrocarbyl substituent of the hydrocarbyl-substituted succinic anhydride has a number average molecular weight of about 900 to about 1500 and is derived from a polyisobutene having greater than 50 mol% of terminal double bonds; and (b) combining about 0.02 to about 5% by weight of the overbased magnesium sulfonate detergent with up to about 0.4 of a glycerol monooleate friction modifier; and wherein the combination of the overbased magnesium sulfonate detergent and the glycerol monooleate friction modifier is storage-stable at about 55 °C for at least about 18 weeks.

11. The method according to claim 10, wherein the overbased magnesium sulfonate has a total base number (TBN) of at least about 450 mg KOH / g before the treatment, and the overbased magnesium sulfonate detergent has a total base number (TBN) of less than about 410 mg KOH / g after the treatment.

12. The method according to claim 10, wherein the overbased magnesium sulfonate detergent comprises at least about 60% by weight of magnesium sulfonate as an active ingredient; and / or wherein the overbased magnesium sulfonate detergent has about 35% by weight or less of a processing oil.

13. The method according to claim 10, wherein the treatment step (c) is substantially free of dicarboxylic acids, and wherein the dicarboxylic acid is one or more of the following: phthalic acid, succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, malonic acid, or combinations thereof.

14. The method according to claim 10, wherein prior to the treatment step (c), the overbased magnesium sulfonate is vacuum stripped at about 160 °C to about 200 °C; and / or wherein the overbased magnesium sulfonate detergent has a total base number (TBN) of about 350 mg KOH / g to about 410 mg KOH / g and is storage stable at about 55 °C for at least about 18 weeks when combined with up to about 0.4% by weight of a glycerol monooleate friction modifier.

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