KR20040077894A - Lubricating oil compositions with improved friction properties - Google Patents

Abstract

The present invention relates to friction reducing agents for use in lubricating oil compositions comprising certain groups of aromatic compounds, esters, narrow mixtures of substrate raw materials, and / or amorphous polymers such as amorphous olefin copolymers. These compositions, when mixed with lubricating oil, can provide advantages such as substantial reduction of coefficient of friction and improved fuel economy without adverse effects such as instability, undesirable high viscosity and precipitation. In one aspect of the invention, pentaerythritol esters and optionally triol esters can be added to the lubricating oil composition to provide reduced friction and improved fuel economy. In a second aspect of the present invention, similar results can be obtained by adding hydrocarbyl aromatic to a lubricating oil composition containing one or more of Group II and Group III based raw materials. In a third aspect, the present invention relates to a lubricating oil composition comprising an amorphous olefin copolymer and at least one of Group II and Group III based raw materials. In one embodiment, the third aspect also includes one or more of the hydrocarbyl aromatic and polyol esters as part of the composition. In a fourth aspect, appropriate concentrations of hydrocarbyl aromatics are used in lubricating oil compositions comprising paraffin base oil and preferably polyisobutenyl succinimide borate ashless dispersant.

Description

LUBRICATING OIL COMPOSITIONS WITH IMPROVED FRICTION PROPERTIES}

Lubricants for internal combustion engines, in addition to one or more lubricant base oils, contain additives that enhance the performance of the lubricant. Various additives such as detergents, dispersants, friction reducers, viscosity index enhancers, antioxidants, corrosion inhibitors, antiwear additives, pour point depressants, seal compatibility additives, and antifoaming agents are used in lubricating oil compositions.

It is important to sufficiently maintain a high lubricating film thickness on the metal surface to maintain low friction and reduce wear of the metal parts at various operating temperatures. It is also important to maintain cleanliness over the full range of operating conditions with minimal wear and tear and to maintain good total lubrication performance even under the most severe operating temperatures. Conventional lubricating oil and engine oil techniques are those that reduce one or more friction classes of compounds, such as alcohols, hydrocarbyl diols, hydrocarbyl triols, alkanes diols or triols, esters, fatty esters, hydroxy esters, fatty acids Amides such as oleamides, hydroxy alkyl hydrocarbyl amides, bis hydroxyalkyl hydrocarbyl amides such as bis (2-hydroxyethyl) oleamides, hydroxy alkyl hydrocarbyl amines, bis hydroxyalkyl hydrocarbyls Amines (e.g. bis (2-hydroxyethyl) oleylamine), the above borate counterparts, the above acylated counterparts, phosphorus based compositions (e.g. trioleyl phosphites), molybdenum compounds (e.g. For example, inorganic molybdenum and / or organic molybdenum compounds such as molybdenum dithiocarbamate, molybdenum force Rodayi thio benzoate, strongly depend on the traditional friction reducer selected from amines and / or molybdenum complexes of the alcohol residue). Friction reducing agents often include mixtures of two or more of the components of this class. Some of the preceding friction reducing compositions often have been found to have significant amounts of undesirable side effects. Therefore, it is desirable to select several improved fuel saving components and / or systems from blends of high quality fuel economy enhancing lubricants.

Summary of the Invention

The present invention relates to a friction reducing agent for use in lubricating oil compositions comprising a specific group of aromatic compounds, esters, substrate raw materials, and / or amorphous polymers such as amorphous olefin copolymers. These compositions can provide the advantages of substantial reduction in coefficient of friction and improved fuel economy without adverse effects such as instability, undesirable high viscosity and precipitation when mixed with lubricating oils.

In one aspect of the invention, pentaerythritol esters and optionally triol esters are added to the lubricating oil composition to provide reduced friction and improved fuel economy. In a second aspect of the invention, hydrocarbyl aromatics are added to a lubricating oil composition containing at least one of a Group II based raw material, a Group III based raw material, and a wax isomerate based raw material to obtain similar results. In a third embodiment, the present invention relates to a lubricating oil composition comprising an amorphous olefin copolymer and at least one of a Group II based raw material, a Group III based raw material and a wax isomerate based raw material. In one embodiment, the third aspect also includes one or more of hydrocarbyl aromatic and polyol esters as part of the composition of the present invention. In a fourth embodiment, a suitable concentration of hydrocarbyl aromatic is used in a lubricating oil composition comprising paraffin base oil and preferably polyisobutenyl succinimide borate ashless dispersant.

The present invention relates to a lubricating oil composition suitable for use in an internal combustion engine.

1 shows the function of temperature and coefficient of friction for various compositions.

Engine oils contain lubricant base oils and various additives. Such additives include detergents, dispersants, friction reducing agents, viscosity index enhancers, antioxidants, corrosion inhibitors, antiwear additives, pour point depressants, seal compatibility additives and antifoaming agents. To be effective, these additives must be oil-soluble or oil-dispersible. Oil-soluble means that the compound is soluble in base oil or lubricating oil compositions under normal mixing conditions.

The present invention provides a narrow mixture of aromatic compounds, esters, substrate raw materials, which can provide substantial reductions in coefficient of friction and improved fuel economy, without adverse effects such as instability, undesirable high viscosity and precipitation when mixed with lubricating oils, and And / or a friction reducing agent for use in a lubricating oil composition of a particular group of amorphous polymers such as amorphous olefin copolymers.

In one aspect, the present invention relates to certain pentaerythritol esters that have been found to provide unexpected significant fuel economy improvement (friction reduction) advantages when formulated with lubricating oils containing hydrocarbyl aromatic compositions. This fuel economy improvement can also be further improved by adding a specific ester to the pentaerythritol ester. In particular, this additional fuel economy improvement is seen in triol and pentaerythritol ester systems mixed in the presence of relatively low concentrations of hydrocarbyl aromatics (eg alkylated naphthalenes). Useful concentrations of hydrocarbyl aromatics are at least about 1%. It is often thought that about 2% to about 45% hydrocarbyl aromatic is more preferred, more preferably about 2 to about 30%, more preferably about 3 to about 15%.

Preferred esters include pentaerythritol esters derived from mono-, di-, and poly-pentaerythritol polyols reacted with mixed hydrocarbyl acid (RCO ₂ H), wherein a significant amount of usable -OH groups are esters Is switched. Substituent hydrocarbyl groups R of acid residues and esters comprise from about C ₆ to about C ₁₆ or more, with preferred ranges from about C ₆ to about C ₁₄ , alkyl, alkenyl, cycloalkyl, cycloalkenyl, linear, branched Chain and related hydrocarbyl groups and optionally contain S, N and / or O groups. Pentaerythritol esters together with mixtures of substituent hydrocarbyl groups R are often preferred. For example, the substituent hydrocarbyl group R contains significant amounts of C ₈ and C ₁₀ hydrocarbyl residues in a ratio of about 1: 4 to 4: 1. In this aspect, preferred pentaerythritol esters have an R group having about 55% C ₈ , about 40% C ₁₀ , and the remainder of approximately 5% C ₆ and C ₁₂₊ residues. For example, one useful pentaerythritol ester has a viscosity index of about 148, a pour point of about 3 ° C and a kinematic viscosity of about 5.9 cSt at 100 ° C. Pentaerythritol ester may be used in the lubricating oil composition at a concentration of about 3 to about 30%, preferably about 4 to about 20%, more preferably about 5 to about 15%.

Esters also include esters such as trimethylolpropane and trimethylolethane.

The hydrocarbyl aromatic that may be used may be any hydrocarbyl molecule containing at least 5% of its weight derived from aromatic residues such as benzenoid residues or naphthenoid residues or derivatives thereof. These hydrocarbyl aromatics include alkyl benzenes, alkyl naphthalenes, alkyl diphenyl oxides, alkyl naphthols, alkyl diphenyl sulfides, alkylated bisphenol A, alkylated thiodiphenols, and the like. The aromatics can be mono-alkylated, dialkylated, polyalkylated and the like. The aromatic may be mono- or multi-functionalized. The hydrocarbyl group may also consist of a mixture of alkyl groups, alkenyl groups, alkynyl, cycloalkyl groups, cycloalkenyl groups and other related hydrocarbyl groups. The hydrocarbyl group may range from about C ₆ to about C _{60, with} the range of about C ₈ to about C ₄₀ often being preferred. Mixtures of hydrocarbyl groups are often preferred. The hydrocarbyl group may optionally contain sulfur, oxygen, and / or nitrogen containing substituents. The aromatic group can also be derived from natural (petroleum) sources, provided that at least about 5% of the molecule consists of aromatic residues of this type. Viscosities at 100 ° C. of about 3 to about 50 cSt are preferred, and viscosity of about 3.4 cSt to about 20 cSt is more preferred for the hydrocarbyl aromatic component. In one embodiment, alkyl naphthalene is used in which the alkyl group consists primarily of 1-hexadecene. Other alkylates of aromatics can be advantageously used. For example, naphthalene may be alkylated with olefins such as octene, decene, dodecene, tetradecene or more, mixtures of similar olefins, and the like. Useful concentrations of hydrocarbyl aromatics in the lubricating oil composition may be about 2 to about 25%, preferably about 4 to about 20%, more preferably about 4 to about 15%, depending on the application.

Alkylated aromatics, such as the hydrocarbyl aromatics of the present invention, can be produced by Friedel-Crafts alkylation of well-known aromatic compounds. See Friedel-Crafts and Related Reactions, Olah, GA (ed). , Interscience Publishers, New York, 1963. For example, aromatic compounds such as benzene or naphthalene are alkylated with olefins, alkyl halides, alcohols in the presence of a Friedel-Craft catalyst. See Friedel-Crafts and Related Reactions, Vol. 2, part 1, chapters 14, 17, and 18, Olah, GA (ed), Interscience Publishers, New York, 1964]. Many homogeneous or heterogeneous solid catalysts are known to those skilled in the art. The choice of catalyst depends on the reactivity of the starting materials and the product quality requirements. For example, strong acids such as AlCl ₃ , BF ₃ , or HF can be used. In some cases, milder catalysts, such as FeCl ₃ or SnCl _4, are preferred. Other alkylation techniques use zeolites or solid super acids.

The fuel economy improvement is manifested as a synergistic mixture of (a) a Group II or III paraffin oil blend, comprising a wax isomerate base oil, and (b) a hydrocarbyl aromatic. In particular, it comprises a specific hydrotreated base oil in the presence of low concentrations of polyol-based esters (eg derived from trimethylolpropane and mixed hydrocarbyl acid) and hydrocarbyl aromatics (eg alkylated naphthalene). The above-mentioned base stocks provide significant unexpected fuel economy (friction reduction) advantages when compared directly to lubricants containing relatively high amounts of about 40% of high quality synthetic fluids derived from olefin oligomers such as 1-decene oligomers. Turned out to be. For comparison, all groups of base stocks have a viscosity of about 4 to about 50 cSt and a similar viscosity index of at least about 110 to about 150 at 100 ° C.

In another aspect of the invention, certain amorphous olefin copolymers are unexpected when formulated with lubricating oils, in particular lubricating oils containing a substantial amount of Group II or Group III base oils, including wax isomerates having a viscosity index of at least about 110 to about 150. It has been found to provide significant fuel economy improvements (reduction of wear). Such olefin copolymers are not predominantly crystalline. The copolymer used in the present invention has a molecular weight of at least about 20,000, preferably at least 60,000, more preferably at least 100,000, more preferably at least 150,000. For example, in one embodiment, the amorphous ethenylene-propylene copolymer comprising significant to most amounts of propylene-derived copolymer has a molecular weight of at least about 20,000. The fuel economy advantage is that the amorphous olefin copolymer is at least about 1% to about 30%, preferably at least about 2% to about 25%, more preferably at about 3% to about 20% of a typical ester such as alkyl naphthalene. And / or when used in finish blended lubricating oils in the presence of hydrocarbyl aromatics.

In the present invention, the use of such amorphous olefin copolymers provides surprising low temperature pumpability in lubricating oil compositions.

In another aspect of the invention, using a suitable concentration of hydrocarbyl aromatic, preferably in the presence of at least small amounts of Group II or Group III hydrocracked and / or hydrotreated substrate stocks (including wax isomerates) Significant fuel economy improvements are achieved. Such hydrocarbyl aromatics have been described above. Group II and Group III based raw materials and wax isomerate based raw materials are described below. The presence of certain ashless dispersants is believed to contribute significantly to the observed fuel economy improvement.

For example, preferred compositions have been found to be particularly useful as long as they include about 20% hydrocarbon aromatics, about 40% Group II paraffin based raw materials, about 3% polyisobutyl succinimide borate ashless dispersant. Useful ashless dispersants are disclosed below.

Group II and / or Group III hydrotreated or hydrolyzed base stocks comprising wax isomerates or their synthetic counterparts such as polyalphaolefin lubricating oils are lubricated when used with the components of each of the above aspects of the invention. Preferred as base oil. At least about 20% of the total composition should comprise a Group II and / or Group III based raw material comprising a wax isomerate, sometimes at least about 30% is more preferred, at least about 50% is more preferred and about 80% The above is more preferable. Gas-to-Liquid (GTL) base stocks may also optionally be used with the components of the invention as part or all of the base stocks used to blend the finished lubricant. Mixtures of all or part of these base stocks are advantageously used and are often preferred. These improvements and advantages may be achieved in lubricating oil systems in which the components of the invention are primarily composed of Group II and / or Group III based raw materials comprising wax isomerates, such as hydrocarbyl aromatics such as C ₁₂ , C ₁₄ , It is believed to be best when used with small amounts of selective fluids such as C ₁₆ and / or C ₁₈ alkylated naphthalene). In some cases, hydrocarbyl aromatic products comprising substantially mono-alkylated naphthalenes are preferred.

Other ingredients, including effective amounts of co-based raw materials and various performance additives, can be advantageously used with the components of the present invention. These co-based raw materials include polyalphaolefin oligomer low viscosity, medium viscosity and high viscosity oils, dibasic acid esters, polyol esters, other hydrocarbon oils such as those derived from GTL type technology, supplemental hydrocarbyl aromatics, and the like. . These co-based raw materials may include a predetermined amount of decene-derived trimers and tetramers, and also a predetermined amount of Group I based raw materials, provided that Group II and / or Group III comprising the wax isomerate Substrate stocks of the type occupy and occupy at least about 50% of the total substrate stock contained in the fluids comprised of the elements of the present invention which require a substantial portion of these stocks. The base raw material, sub-base raw material and other performance additives are described in more detail below.

The present invention provides effective amounts of additional lubricating oil components (eg, polar and / or nonpolar lubricants) and performance additives in the lubricating oil compositions such as, but not limited to, antioxidants, metal and nonmetallic dispersants, metal and nonmetallic detergents, corrosion and Rust inhibitors, metal deactivators, antiwear agents (metals and nonmetals, phosphorus- and non-phosphorus, sulfur- and non-sulfur types), extreme pressure additives (metals and nonmetals, phosphorus- and non-phosphorus, sulfur- and sulfur-based Types), anti-seizure agents, pour point depressants, wax modifiers, viscosity modifiers, seal stabilizers, friction modifiers, lubricants, antifouling agents, colorants, antifoams, emulsifiers, and the like. For many commonly used additives, see the following references: Klamann in Lubricants and Related Products, Verlag Chemie, Deerfield Beach, FL .; ISBN 0-89573-177-0]. The document also discusses a number of lubricant additives discussed below. See also, "Lubricant Additives", M. W. Ranney, Noyes Data Corporation of Parkridge, N.J. (1973).

Base oil

A wide range of lubricants are known in the art. Lubricants useful in the present invention are natural and synthetic oils. Natural and synthetic oils (or mixtures thereof) may be used in the crude, refined or refined state (also known as recycled or reprocessed oil). Crude oil is obtained directly from natural or synthetic sources and used without further purification. These include sail oil obtained directly from the retort operation, petroleum obtained directly from the primary distillation, and ester oil obtained directly from the esterification process. Refined oils are similar to the oils discussed for crude oil except that it is introduced into one or more refining steps to improve one or more lubricant properties. Those skilled in the art will be familiar with many purification methods. These methods include solvent extraction, secondary distillation, acid extraction, base extraction, filtration and pore perfusion. The refined oil is obtained using the oil used in the unit by a method similar to refined oil.

Groups I, II, III, IV and V are a broad range of base oils developed and defined by the American Petroleum Institute (API Publication 1509; www.API.org ). Group I based raw materials generally have a viscosity index of about 80 to 120 and contain at least about 0.03% sulfur and / or less than about 90% saturates. Group II based raw materials generally have a viscosity index of about 80 to 120 and contain up to about 0.03% sulfur and at least about 90% saturates. Group III raw materials generally have a viscosity index of at least about 120 and contain up to about 0.03% sulfur and at least about 90% saturates. Group IV includes polyalphaolefins (POA). Group V base raw materials include base raw materials not included in Groups I to IV. The table below summarizes the characteristics of each of these five groups.

Natural oils include animal oils, vegetable oils (eg castor oil and lard oil) and inorganic oils. Treatment of animal and vegetable oils may yield advantageous thermal oxidative stability. Of the natural oils, inorganic oils are preferred. Inorganic oils are very broad, depending on their crude source, for example paraffinic, naphthenic or mixed paraffinic-naphthenic. Oils derived from char or sail are also useful in the present invention. Natural oils also vary according to the methods used for their preparation and purification, such as the distillation range and whether they are carried out directly, decomposed, hydrogen purified or solvent extracted.

Synthetic oils include hydrocarbon oils. Hydrocarbon oils include oils such as polymerized olefins and interpolymerized olefins (eg, polybutylene, polypropylene, propylene isobutylene copolymers, ethylene-olefin copolymers and ethylene-alphaolefin copolymers). Polyalphaolefin (PAO) oil based raw materials are commonly used synthetic hydrocarbon oils. For example, PAO derived from C ₈ , C ₁₀ , C ₁₂ , C ₁₄ olefins or mixtures thereof can be used. See US Pat. Nos. 4,956,122, 4,827,064 and 4,827,073, which are hereby incorporated by reference in their entirety.

Number average molecular weights of PAOs that are known and generally available from major sources such as ExxonMobil Chemical Company, Chevron-Phillips, BP-Amoco, etc. Silver is generally about 250 to about 3,000, although PAO consists of a viscosity of about 100 cSt or less (100 ° C.). PAOs are generally relatively non-limiting of alpha olefins, including C ₂ to about C ₃₂ alpha olefins, preferably C ₈ to about C ₁₆ alpha olefins, for example 1-octene, 1-decene, 1-dodecene. Low molecular weight hydrogenated polymers or oligomers. Preferred polyalphaolefins are poly-1-octene, poly-1-decene and poly-1-dodecene and mixtures thereof and mixed olefin-derived polyolefins. However, dimers of higher olefins in the range of C ₁₄ to C ₁₈ can be used to provide a low viscosity base stock of an acceptable low volatility. Depending on the viscosity grade and the starting oligomer, PAOs are mostly trimers and tetramers of the starting olefins, only small amounts are higher oligomers and have a viscosity of 1.5 to 12 cSt.

PAO fluids can be prepared by the use of polymerization catalysts such as preedel-craft catalysts (e.g., aluminum trichloride, boron trifluoride or boron trifluoride) and esters such as alcohols such as water, ethanol, propanol or butanol, carboxylic acids, ethyl acetate or ethyl propionate Complex compounds), which can be prepared conventionally by polymerization of alpha olefins. For example, the methods disclosed in US Pat. No. 4,149,178 or 3,382,291 are commonly used herein. PAO synthesis is disclosed in US Pat. Nos. 3,742,082, 3,769,363, 3,876,720, 4,239,930, 4,367,352, 4,413,156, 4,434,408, 4,910,355, 4,956,122 and 5,068,487. Dimers of C ₁₄ to C ₁₈ olefins are disclosed in US Pat. No. 4,218,330. All of these patents are incorporated herein by reference in their entirety.

Other useful synthetic lubricating base oils disclosed in, for example, the following documents, which are hereby incorporated by reference in their entirety, may also be used. See, "Synthetic Lubricants", Gunderson and Hart, Reinhold Publ. Corp., New York 1962].

Among the alkylated aromatic raw materials, alkyl substituents are generally alkyl groups having 8 to 25 carbon atoms, typically 10 to 18 carbon atoms, and up to three such substituents may be present, as described for alkyl benzene in the following literature. Petroleum Chemistry Preprint 1053-1058, "Poly n-Alkylbenzene Compounds: A Class of Thermally Stable and Wide Liquid Range Fluids", Eapen et al., Phila. 1984]. Trialkyl benzenes can be produced by ring propolymerization of 1-alkaine of 8 to 12 carbon atoms as disclosed in US Pat. No. 5,055,626. Other alkylbenzenes are disclosed in European Patent Application No. 168534 and US Patent No. 4,658,072. Alkylbenzenes are used in particular as lubricant base oils and for papermaking oils for low temperature applications (Polar vehicle service and refrigerated oil). These are linear alkyls such as Vista Chem. Co, Huntsman Chemical Co., Chevron Chemical Co., and Nippon Oil Co. It is commercially available from the producer of benzene (LAB). Such linear alkylbenzenes generally have good low pour points and low temperature viscosities and viscosity index values greater than 100 and good solubility for additives. Other alkylated aromatics that can be used when needed are described, for example, in "Synthetic Lubricants and High Performance Functional Fluids", Dressler, H., chap 5, (RL Shubkin (Ed.)), Marcel Dekker, NY 1993].

Other useful lubricant base oils include base oils, hydroisomerized Fischer-Tropsch (Fischer), including wax isomerate based raw materials and hydroisomerized wax raw materials (e.g., gas oils, slack waxes, fuel hydrocracked tower oils, etc.). -Tropsch) waxes, GTL based raw materials and base oils, and other wax isomerate hydroisomerized based raw materials and base oils, or mixtures thereof. Fischer Tropsch wax, the high boiling point residue of Fischer Tropsch synthesis, is a highly paraffinic hydrocarbon with very low sulfur content. The hydrotreatment used in the production of these base stocks may utilize amorphous hydrocracking / hydroisomerization catalysts such as specialized lubricating oil hydrocracking (LHDC) catalysts or crystalline hydrocracking / hydroisomerization catalysts, preferably zeolite catalysts. have. For example, one useful catalyst is ZSM-48 disclosed in US Pat. No. 5,075,269, which is incorporated herein by reference in its entirety. Methods for the preparation of hydrocracked / hydroisomerized distillates and hydrocracked / hydroisomerized waxes are described in U.S. Pat. 1,440,230 and 1,390,359. Each of these patents is hereby incorporated by reference in their entirety. Particularly preferred methods are disclosed in European patent applications 464546 and 464547, which are incorporated herein by reference. Methods of using Fischer Tropsch wax feeds are disclosed in US Pat. Nos. 4,594,172 and 4,943,672. GTL base oils, Fischer-Tropsch wax-derived base oils and other wax-derived hydroisomerized (wax isomerate) base oils are preferably used in the present invention and are used in the range of about 3 to about 50 cSt, preferably about 3 to about 30 cSt. And, more preferably, can have a useful kinematic viscosity at 100 ° C. of about 3.5 to about 25 cSt, and can be represented by GTL 4 having a kinematic viscosity of about 4.0 cSt and a viscosity index of about 141 at 100 ° C. GTL base oils, Fischer Tropsch wax-derived base oils and other wax-derived hydroisomerized base oils can have useful pour points up to about -20 ° C. and under some conditions can have advantageous pour points up to about -25 ° C. and useful pour points Is about -30 to -40 ° C. Useful compositions of GTL base oils, Fischer-Tropsch wax derived base oils, and wax-derived hydroisomerized base oils are disclosed in US Pat. Nos. 6,080,301, 6,090,989, and 6,165,949, which are incorporated herein in their entirety. .

GTL base oils, Fischer-Tropsch wax derived base oils have the advantage of favorable kinematic viscosity over conventional Group II and Group III base oils, which are very advantageously used in the present invention. GTL base oils can have a fairly high kinematic viscosity at 100 ° C. up to about 20-50 cSt, while conventional Group II base oils can have a kinematic viscosity at 100 ° C. up to about 15 cSt and a typical Group III base oil at 100 ° C. It may have a kinematic viscosity of about 10 cSt or less. The higher kinematic viscosity range of GTL base oils as compared to the more limited kinematic viscosity ranges of Group II and Group III base oils can provide additional advantageous advantages in formulating lubricating oil compositions when combined with the present invention. In addition, the exceptionally low sulfur content and other wax-derived hydroisomerized base oils of the base oils of GTL have very low total sulfur contents when the appropriate olefin oligomers and / or alkyl aromatic base oils are combined with the present invention with low sulfur content. It can advantageously provide further advantages in lubricating oil compositions that can affect lubricating oil performance.

Alkylene oxide polymers and interpolymers and their derivatives containing modified terminal hydroxyl groups obtained, for example, by esterification or etherification, are useful synthetic lubricants. By way of example, these oils may be polymerized with ethylene oxide or propylene oxide, alkyl and aryl ethers of these polyoxyalkylene polymers (e.g., methyl-polyisopropylene glycol ethers having an average molecular weight of about 1000, molecular weights of about 500 to 1000). Diphenyl ether of polyethylene glycol having, and diethyl ether of polypropylene glycol having a molecular weight of about 1000 to 1500) or their mono- and poly-carboxylic acid esters (acidic acid esters, mixed C _3-8 fatty acid esters, or tetra C ₁₃ oxo acid diesters of ethylene glycol).

Esters include useful substrate raw materials. Additive solubility and sealing suitability can be assured using esters such as esters of dibasic acids and monoalkanols and polyesters of monocarboxylic acids. Esters of the electronic type are, for example, phthalic acid, succinic acid, alkyl succinic acid, alkenyl succinic acid, maleic acid, azalaic acid, suveric acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkyl Esters of dicarboxylic acids such as malonic acid, alkenyl malonic acid and various alcohols such as butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, and the like. Specific examples of these types of esters are dibutyl adipate, di (2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azlate, diisodecyl azlate, dioctyl Phthalates, diedecyl phthalates, diecosyl sebacates and the like.

Particularly useful synthetic esters are one or more polyhydric alcohols, preferably hindered polyols (eg neopentyl polyols such as neopentyl glycol, trimethylol ethane, 2-methyl-2-propyl-1,3-propane) Alkanoic acid (preferably caprylic acid, campanic acid, lauric acid, myristic acid, palmitic acid) having at least about 4 carbon atoms for diols, trimethylol propane, pentaerythritol and dipentaerythritol , Saturated straight chain fatty acids such as stearic acid, arachidic acid, and corresponding branched fatty acids or unsaturated fatty acids such as oleic acid or C ₅ to C ₃₀ acids such as mixtures of these substances).

Suitable synthetic ester components include esters of trimethylol propane, trimethylol butane, trimethylol ethane, pentaerythritol and / or dipentaerythritol with one or more monocarboxylic acids having from about 5 to about 10 carbon atoms. These esters are commercially widely available and include, for example, Mobil P-41 and P-51 esters (ExxonMobil Chemical Company).

Silicone oils are another class of useful synthetic lubricants. These oils include polyalkyl-, polyaryl-, polyalkoxy-, and polyaryloxy-siloxane oils and silicate oils. Examples of suitable silicone oils include tetraethyl silicate, tetraisopropyl silicate, tetra-2 (-ethylhexyl) silicate, tetra- (4-methyl-hexyl) silicate, tetra- (pt-butylphenyl) silicate, hexyl-4 (-Methyl-2-pentoxy) disiloxane, poly (methyl) siloxane and poly- (methyl-2-methylphenyl) siloxane.

Another class of synthetic lubricants is esters of phosphorus-containing acids. These include, for example, tricresyl phosphate, trioctyl phosphate, diethyl ester of decanephosphonic acid. Another class of oils includes polymer tetrahydrofuran and the like.

In addition to the unique additive effects of the hydrocarbyl aromatic and high molecular weight olefin oligomers of the present invention, highly refined low sulfur group II / III base oils (e.g., hydrogenated oil, HDP) and wax isomerate base oils can be substituted for Group IV and V base oils. It is contemplated that it may be used as a base material used in conjunction with or in addition to the components of the present invention to provide the above mentioned excellent performance characteristics.

The type and amount of performance additive used with the present invention in the lubricating oil composition is not limited by the examples shown herein.

Wear Resistant and EP Additives

Internal combustion engine lubricating oils require the presence of wear and / or extreme pressure (EP) additives to provide proper wear resistance of the engine. Details of engine oil performance have increasingly turned to the improved wear resistance of the oil. Wear and extreme pressure EP additives play a role by reducing friction and wear of metal parts.

Although many different types of antiwear additives have existed for decades, the main antiwear additives for internal combustion engine crankcase oils are metal alkylthiophosphates, more specifically primary metal components zinc, or zinc dialkyldithio. Metal dialkyldithio phosphate that is phosphate (ZDDP). ZDDP compounds are generally of the general formula Zn [SP (S) (OR ¹ ) (OR ² )] ₂ , wherein R ¹ and R ² are C ₁ -C ₁₈ alkyl groups, preferably C ₂ -C ₁₂ alkyl groups Has These alkyl groups can be straight or branched chain. ZDDP is generally used in amounts of about 0.4 to 1.4 weight percent of the total lubricating oil composition, although sometimes some amount may be advantageously used.

However, it has been found from these additives that phosphorus adversely affects the catalyst phase in the catalytic converter and also adversely affects the oxygen sensor in automobiles. One way to minimize this effect is to replace some or all of the ZDDP with a phosphorus-free antiwear additive.

Various non-phosphorus additives are also used as antiwear additives. Sulfurized olefins are useful as antiwear and EP additives. Sulfur-containing olefins may be prepared by sulfidation or by various organic materials including aliphatic, arylaliphatic or cycloaliphatic olefin hydrocarbons having about 3 to 30 carbon atoms, preferably 3 to 20 carbon atoms. The olefin compound contains one or more non-aromatic double bonds. Such compounds are defined by Formula I:

R ³ R ⁴ C = CR ⁵ R ⁶

Where

R ³ to R ⁶ are independently hydrogen or hydrocarbon radicals. Preferred hydrocarbon radicals are alkyl or alkenyl radicals. Any two of R ³ to R ⁶ may be linked to form a cyclic ring. Additional information relating to sulfided olefins and their preparation is disclosed in US Pat. No. 4,941,984, which is incorporated herein by reference.

The use of polysulfides of thiophosphoric and thiophosphoric esters as lubricant additives is disclosed in US Pat. Nos. 2,443,264, 2,471,115, 2,526,497 and 2,591,577. The addition of phosphorothionyl polysulfides as antiwear, antioxidant and EP additives is disclosed in US Pat. No. 3,770,854. Alkylthiocarbamoyl compounds such as molybdenum compounds (e.g., oxymolybdenum diisopropylphosphorodithioate sulfides) and phosphorus esters (e.g. dibutyl hydrogen phosphite) as abrasion resistant additives in lubricants The use of bis (dibutyl) thiocarbamoyl) is disclosed in US Pat. No. 4,501,678. U.S. Patent No. 4,758,362 discloses the use of carbamate additives to provide improved wear and extreme pressure properties. The use of thiocarbamates as antiwear additives is disclosed in US Pat. No. 5,693,598. Thiocarbamate / molybdenum complexes such as moly-sulfur alkyl dithiocarbamate trimer complexes (R═C ₈ -C ₁₈ alkyl) are also useful antiwear agents. Each of these patents is incorporated herein by reference in its entirety.

Esters of glycerol can be used as antiwear agents. For example, mono-, di-, and tri-oleates, mono-palmitates and mono-myristates can be used.

ZDDP is combined with other compositions that provide wear resistance. U.S. Pat.No. 5,034,141 discloses that a combination of a thiodigentogen compound (e.g. octylthiodogenogen) and a metal thiophosphate (e.g. ZDDP) can improve wear resistance. U.S. Patent No. 5,034,142 discloses improved abrasion resistance when a combination of metal alkoxyalkylgentate (e.g. nickel ethoxyethylgentate) and diezentogen (e.g. diethoxyethyl diegentogen) and ZDDP is used. It is disclosed. Each of these patents is incorporated herein by reference in their entirety.

Preferred antiwear additives are phosphorus and sulfur compounds such as zinc dithiophosphate and / or various organo-molybdenum derivatives including sulfur, nitrogen, boron, molybdenum phosphorodithioate, molybdenum dithiocarbamate and heterocyclic , For example dimercaptothiadiazole, mercaptobenzothiadiazole, triazine and the like, and alicyclic, amine, alcohol, ester, diol, triol, fatty amide and the like can be used. Such additives may be used in amounts of about 0.01 to 6% by weight, preferably about 0.01 to 4% by weight.

Viscosity Index Improver

Viscosity index improvers (known as VI enhancers, viscosity modifiers and viscosity improvers) provide lubricants with high and low temperature workability. These additives impart shear stability at high temperatures and acceptable viscosity at low temperatures.

Suitable viscosity index improvers include high molecular weight hydrocarbons, polyesters and viscosity index improver dispersants that function as both viscosity index improvers and dispersants. Typical molecular weights of these polymers are about 10,000 to 1,000,000, more preferably about 20,000 to 500,000, more preferably about 50,000 to 200,000.

Examples of suitable viscosity index improvers are polymers and copolymers of methacrylate, butadiene, olefins or alkylated styrenes. Polyisobutylene is a commonly used viscosity index improver. Another suitable viscosity index improver is polymethacrylate (eg, copolymers of alkyl methacrylates of various chain lengths), some of which also act as pour point depressants. Other suitable viscosity index improvers include copolymers of ethylene and propylene, hydrogenated block copolymers of styrene and isoprene and polyacrylates (eg, copolymers of acrylates of various chain lengths). Specific examples include styrene-isoprene or styrene-butadiene-based polymers having a molecular weight of 50,000 to 200,000.

Viscosity index improvers may be used in amounts of about 0.01 to 8% by weight, preferably about 0.01 to 4% by weight.

Antioxidant

Antioxidants delay the oxidative decomposition of base oils during operation. This degradation can cause precipitation on the metal surface, the presence of sludge or an increase in viscosity in the lubricating oil. Those skilled in the art will know a wide variety of antioxidants useful in lubricating oil compositions. See Klamann in Lubricants and Related Products (cited above) and US Pat. Nos. 4,798,684 and 5,084,197, which are hereby incorporated by reference in their entirety.

Useful antioxidants include hindered phenols. These phenolic antioxidants may be ashless (metal free) phenolic compounds or neutral or basic metal salts of certain phenolic compounds. Typical phenolic antioxidant compounds are hindered phenols which contain sterically hindered hydroxyl groups, which include derivatives of divalent aryl compounds in which the hydroxyl groups are in the o- or p-position relative to one another. Common phenolic antioxidants include hindered phenols substituted with C ₆₊ alkyl groups and alkylene coupled derivatives of these hindered phenols. Examples of phenolic substances of this type include 2-t-butyl-4-heptyl phenol, 2-t-butyl-4-octyl phenol, 2-t-butyl-4-dodecyl phenol, 2,6-di-t- Butyl-4-heptyl phenol, 2,6-di-t-butyl-4-dodecyl phenol, 2-methyl-6-t-butyl-4-heptyl phenol, and 2-methyl-6-t-butyl-4 There is dodecyl phenol. Other useful hindered mono-phenolic antioxidants include, for example, hindered 2,6-di-alkylphenol proprioone ester derivatives. Bisphenolic antioxidants can also be advantageously used in combination with the present invention. Examples of other coupled phenols are 2,2'-bis (6-t-butyl-4-heptyl phenol), 2,2'-bis (6-t-butyl-4-octyl phenol) and 2,2 ' -Bis (6-t-butyl-4-dodecyl phenol). Para-coupled bisphenols include, for example, 4,4'-bis (2,6-di-t-butyl phenol) and 4,4'-methylene-bis (2,6-di-t-butyl phenol) do.

Non-phenolic antioxidants that can be used include aromatic amine antioxidants and can be used alone or in combination with phenols. General examples of non-phenolic antioxidants are alkylated and non-alkylated aromatic amines, for example general formula R ⁸ R ⁹ R ¹⁰ N [where R ⁸ is an aliphatic, aromatic or substituted aromatic group and R ⁹ is aromatic Or a substituted aromatic group, R ¹⁰ is H, alkyl, aryl or R ¹¹ S (O) xR ¹² wherein R ¹¹ is an alkylene, alkenylene, or aralkylene group, and R ¹² is a higher alkyl group, al Is a kenyl, aryl, or alkaryl group, x is 0, 1, or 2). Aliphatic R ⁸ has 1 to about 20 carbon atoms, preferably about 6 to 12 carbon atoms. Such aliphatic groups are saturated aliphatic groups. Preferably, both R ⁸ and R ⁹ are aromatic or substituted aromatic groups, said aromatic groups may be conjugated ring aromatic groups such as naphthyl. Aromatic groups R ⁸ and R ⁹ may be bonded together with other groups such as S.

Typical aromatic amine antioxidants have alkyl substituents of about 6 or more carbon atoms. Examples of aliphatic groups include hexyl, heptyl, octyl, nonyl and decyl. Generally, aliphatic groups contain up to about 14 carbon atoms. Common types of amine antioxidants useful in the compositions of the present invention include diphenylamine, phenyl naphthylamine, phenothiazine, imidodibenzyl and diphenyl phenylene diamine. Mixtures of two or more aromatic amines are also useful. Polymeric amine antioxidants may also be used. Specific examples of aromatic amine antioxidants useful in the present invention include p, p'-dioctyldiphenylamine, t-octylphenyl-alpha-naphthylamine, phenyl-alphanaphthylamine and p-octylphenyl-alpha-naphthylamine It includes.

Sulfated alkyl phenols and their alkali or alkaline earth metal salts are also useful antioxidants. Low sulfur peroxide decomposers are useful as antioxidants.

Another class of antioxidants used in lubricating oil compositions are oil soluble copper compounds. Suitable copper compounds of any oiliness can be blended into the lubricant. Examples of suitable copper antioxidants include copper dihydrocarbyl thio or dithio-phosphate and copper salts (naturally occurring or synthetic) of carboxylic acids. Other suitable copper salts include copper dithiocarbamate, sulfonate, phenate and acetylacetonate. Basic, neutral or acidic copper Cu (I) and / or Cu (II) salts derived from alkenyl succinic acids or acid anhydrides are known to be particularly useful.

Preferred antioxidants include hindered phenols, arylamines, low sulfur peroxide decomposers and other related ingredients. These antioxidants can be used individually or in combination with each other depending on the type. Such additives may be used in amounts of about 0.01 to 5% by weight, preferably about 0.01 to 1.5% by weight.

Freshener

Detergents are commonly used in lubricating oil compositions. Common detergents are anionic materials containing the long chain lipophilic portion of the molecule and small amounts of anionic or oleophobic portions of the molecule. The anionic portion of the detergent is generally derived from organic acids such as sulfuric acid, carboxylic acids, phosphoric acid, phenols or mixtures thereof. Counter ions are generally alkaline earth metals or alkali metals.

Salts containing substantially stoichiometric amounts of metals are described as neutral salts and have a total base number of 0 to 80 (TBN measured by ASTM D2896). Many compositions are overbased and contain large amounts of metal bases achieved by the reaction of excess metal compounds (such as metal hydroxides or oxides) with acidic gases (carbon dioxide). Useful detergents may be neutral, mildly overbased, or highly overbased.

It is preferred that at least some degree of detergent be overbased. Overbased detergents help neutralize the acidic impurities produced by the combustion process and are bound in the oil. In general, overbased materials have a ratio of metal ions to anionic portions of a detergent of about 1.05: 1 to 50: 1 on an equivalent basis. More preferably, the ratio is about 4: 1 to about 25: 1. The resulting detergents are generally overbased detergents having a TBN of at least about 150, often at least about 250 to 450. Preferably, the overbased cation is sodium, calcium or magnesium. Mixtures of detergents that differentiate TBN can be used in the present invention.

Preferred detergents include alkali or alkaline earth metal salts of sulfates, phenates, carboxylates, phosphates and salicylates.

Sulfonates can generally be prepared from sulfonic acids obtained by sulfonation of alkyl substituted aromatic hydrocarbons. Hydrocarbon examples include those obtained by alkylating benzene, toluene, xylene, naphthalene, biphenyl and their halogenated derivatives such as chlorobenzene, chlorotoluene and chloronaphthalene. The alkylating agent generally has about 3 to 70 carbon atoms. The alkali sulfonates generally contain about 9 to about 80 or more carbon atoms, more generally about 16 to 60 carbon atoms.

Klamann in Lubricants and Related Products, cited above, discloses a number of overbased metal salts of various sulfonic acids useful as detergents and dispersants in lubricating oils. Likewise, "Lubricant Additives", C. V. Smallheer and R. K. Smith, Lezius-Hiles Co., Cleveland, Ohio (1967) disclose a number of overbased sulfonates useful as dispersants / cleaners.

Alkaline earth metal phenates are another useful class of cleaning agents. These detergents can be prepared by reacting alkaline earth metal hydroxides or oxides (CaO, Ca (OH) ₂ , BaO, Ba (OH) ₂ , MgO, Mg (OH) ₂ ) with alkyl phenols or sulfided alkylphenols. Useful alkyl groups include straight or branched C ₁ -C ₃₀ alkyl groups, preferably C ₄ -C ₂₀ . Examples of suitable phenols include isobutylphenol, 2-ethylhexylphenol, nonylphenol, 1-ethyldecylphenol, and the like. It should be noted that the starting alkylphenols may each contain one or more alkyl substituents, each independently straight or branched. If non-sulfurized alkylphenols are used, the sulfided products can be obtained by methods well known in the art. Such methods include heating a mixture of alkylphenols and sulfiding agents (including elemental sulfur, sulfur halides such as sulfur dichloride, etc.) and reacting the sulfided phenols with alkaline earth metal bases.

Metal salts of carboxylic acids are also useful as detergents. These carboxylic acid detergents can be prepared by reacting a basic metal compound with one or more carboxylic acids and removing free water from the reaction product. These compounds can be overbased to produce the desired amount of TBN. Detergents made from salicylic acid are one preferred class of detergents derived from carboxylic acids. Useful salicylates include long chain alkyl salicylates. One useful class of compositions has Formula II:

Where

R is a hydrogen atom or an alkyl group having 1 to about 30 carbon atoms, n is an integer of 1 to 4, and M is an alkaline earth metal. Preferred R groups are C ₁₁ or more, preferably C ₁₃ or more alkyl chains. R may be optionally substituted with substituents that do not interfere with the function of the detergent. M is preferably calcium, magnesium or barium. More preferably, M is calcium.

Hydrocarbyl substituted salicylic acid can be prepared from phenol by Kolbe reaction. For additional information on the synthesis of these compounds, see US Pat. No. 3,595,791, which is incorporated herein by reference in its entirety. Metal salts of hydrocarbyl-substituted salicylic acid can be prepared by double decomposition of metal salts in polar solvents such as water or alcohols.

Alkaline earth metal phosphates are also used as cleaning agents.

The detergent may be a simple detergent or a complex detergent known as a hybrid. The latter can provide the properties of the two detergents without the need to mix separate materials. See, eg, US Pat. No. 6,034,039. Preferred detergents include calcium phenate, calcium sulfonate, calcium salicylate, magnesium phenate, magnesium sulfonate, magnesium salicylate and other related compounds (including borated detergents). Generally, the total detergent concentration is about 0.01 to about 6.0 weight percent, preferably about 0.1 to 0.4 weight percent.

Dispersant

During engine operation, oil insoluble oxidation by-products are produced. Dispersants help keep these byproducts in solution and thus reduce these precipitations on the metal surface. Dispersants are essentially free of ash or form ash. Preferably, the dispersant is ashless. So-called ashless dispersants are organic materials that do not substantially form ash upon combustion. For example, non-metal-containing or metal-borate-free dispersants are considered stepless. In contrast, the above-mentioned metal-containing detergents form ash upon combustion.

Suitable dispersants generally contain polar groups attached to relatively high molecular weight hydrocarbon chains. The polar group generally contains one or more elements of nitrogen, oxygen or phosphorus. Typical hydrocarbon chains contain 50 to 400 carbon atoms.

Chemically, many dispersants may be characterized by phenates, sulfonates, sulfide phenates, salicylates, naphthenates, stearates, carbamates, thiocarbamates, phosphorus derivatives. Particularly useful classes of dispersants are generally long-chain substituted alkenyl succinic compounds, typically alkenylsuccinic derivatives produced by the reaction of substituted succinic anhydrides with polyhydroxy or polyamino compounds. The long chain constituting the lipophilic molecular moiety that imparts solubility in oil is typically a polyisobutylene group. Many examples of this type of dispersant are well known commercially and are known in the literature. Exemplary US patents describing such dispersants include 3,172,892, 3,2145,707, 3,219,666, 3,316,177, 3,341,542, 3,444,170, 3,454,607, 3,541,012, 3,630,904, 3,632,511, 3,787,374 and 4,234,435. Other types of dispersants include U.S. Patents 3,036,003, 3,200,107, 3,254,025, 3,275,554, 3,438,757, 3,454,555, 3,565,804, 3,413,347, 3,697,574, 3,725,277, 3,725,480 3,726,882, 4,454,059, 3,329,658, 3,449,250, 3,519,565, 3,666,730, 3,687,849, 3,702,300, 4,100,082, 5,705,458. Further dispersants are disclosed, for example, in European Patent Application No. 471 071, to which reference is hereby made. Each of the aforementioned patents is incorporated herein by reference.

Hydrocarbyl-substituted succinic acid compounds are noted dispersants. In particular, succinimides, succinate esters or succinate ester amides which are preferably prepared by the reaction of hydrocarbon-substituted succinic acid compounds having at least 50 carbon atoms with at least one equivalent of alkylene amine in hydrocarbon substituents.

Succinimide is formed by the condensation reaction between alkenyl succinic anhydrides and amines. The molar ratio can vary depending on the polyamine. For example, the molar ratio of alkenyl succinic anhydride to TEPA is about 1: 1 to about 5: 1. Representative examples are disclosed in US Pat. Nos. 3,087,936, 3,172,892, 3,219,666, 3,272,746, 3,322,670 and 3,652,616, 3,948,800 and Canadian Patent 1,094,044, which are hereby incorporated by reference in their entirety. .

Succinate esters are formed by the condensation reaction between alkenyl succinic anhydrides and alcohols or polyols. The molar ratio varies depending on the alcohol or polyol used. For example, condensation products of alkenyl succinic anhydride and pentaerythritol are useful dispersants.

Succinate ester amides are formed by the condensation reaction between alkenyl succinic anhydrides and alkanol amines. For example, suitable alkanol amines include ethoxylated polyalkylpolyamines, propoxylated polyalkylpolyamines and polyalkenylpolyamines such as polyethylene polyamines. One example is propoxylated hexamethylenediamine. Representative examples are shown in US Pat. No. 4,426,305, which is incorporated herein by reference.

The molecular weight of the alkenyl succinic anhydride used in this paragraph is generally from 800 to 2,500. The product may be post-reacted with various reagents such as sulfur, oxygen, formaldehyde, carboxylic acids such as oleic acid, and boron compounds such as borate esters or borate high content dispersants. The dispersant may be borated to about 0.1 to about 5 moles of boron per mole of dispersant reaction product.

Mannich base dispersants are formed from the reaction of alkylphenols, formaldehyde, and amines. See US Pat. No. 4,767,551, which is incorporated herein by reference. Reaction aids and catalysts such as oleic acid and sulfonic acid may be part of the reaction mixture. The molecular weight of alkylphenols is 800 to 25,000. Representative examples are disclosed in US Pat. Nos. 3,697,574, 3,703,536, 3,704,308, 3,751,365, 3,756,953, 3,798,165, and 3,803,039, which are incorporated herein by reference.

Typical high molecular weight aliphatic acid modified Mannich condensation products useful in the present invention can be prepared from high molecular weight alkyl-substituted hydroxyaromatics or HN (R) ₂ group-containing reactants.

Examples of high molecular weight alkyl-substituted hydroxyaromatic compounds are polypropylphenols, polybutylphenols and other polyalkylphenols. These polyalkylphenols may alkylate phenol with high molecular weight polypropylene, polybutylene and other polyalkylene compounds in the presence of an alkylation catalyst such as BF ₃ to provide alkyl substituents on the benzene ring of phenols having an average molecular weight of 600 to 100,000 molecular weight. Can be.

Examples of HN (R) ₂ group-containing reactants are alkylene polyamines, mainly polyethylene polyamines. Other representative organic compounds containing at least one HN (R) ₂ group suitable for use in the preparation of the Mannich condensation product are well known and are mono- and di-amino alkanes and their substituted analogs such as ethylamine and Diethanol amines; Aromatic diamines such as phenylene diamine, diamino naphthalene; Heterocyclic amines such as morpholine, pyrrole, pyrrolidine, imidazole, imidazoline and piperidine; Melamine and substituted analogs thereof.

Examples of alkylene polyamide reactants include alkylene polyamines of the general formula H ₂ N- (Z-NH-) _n H, wherein Z is divalent ethylene and n is 1 to 10 of the above formula. Ethylenediamine, diethylene triamine, triethylene tetraamine, tetraethylene pentaamine, pentaethylene hexamine, hexaethylene heptaamine, heptaethylene octaamine, octaethylene nonaamine, nonaethylene decaamine and the corresponding nitrogen moieties and Decaethylene undecamine and mixtures of these amines. Corresponding propylene polyamines such as propylene diamine and di-, tri-, tetra-, pentapropylene tri-, tetra-, penta- and hexaamines are also suitable reactants. The alkylene polyamines are usually obtained by the reaction of ammonia and dihalo alkanes, for example dichloro alkanes. Thus, the alkylene polyamines obtained from the reaction of 2 to 11 moles of ammonia with 1 to 10 moles of dichloro alkanes having 2 to 6 carbon atoms and chlorine on different carbons are suitable alkylene polyamine reactants.

Aldehyde reactants useful in the preparation of the polymeric products useful in the present invention include aliphatic aldehydes such as formaldehyde (also as paraformaldehyde and formalin), acetaldehyde and aldol (b-hydroxybutyraldehyde). Formaldehyde or formaldehyde-receiving reactants are preferred.

Hydrocarbyl substituted amine ashless dispersant additives are well known to those skilled in the art. See, for example, US Pat. Nos. 3,275,554, 3,438,757, 3,565,804, 3,755,433, 3,822,209, and 5,084,197, which are hereby incorporated by reference in their entirety.

Preferred dispersants include succinimide borates and non-borate salts, including derivatives derived from mono-succinimides, bis-succinimides and / or mixtures of mono- and bis-succinimides, wherein the hydrocarbyl succinimides A hydrocarbylene group such as polyisobutylene or a mixture of such hydrocarbylene groups of about 500 to about 5000, preferably about 1000 to 3000, more preferably about 1000 to 2000, more preferably about 1000 to 1600 Derived from). Other preferred dispersants include succinic acid-esters and amides, alkylphenol-polyamine coupled Mannich adducts, blocked derivatives thereof, and other related components. Such additives may be used in amounts of about 0.1 to 20% by weight, preferably about 0.1 to 8% by weight.

Pour point depressant

Conventional pour point depressants (also known as lubricant flow enhancers) may optionally be added to the compositions of the present invention. These pour point depressants are added to the lubricating oil composition of the present invention to lower the minimum temperature at which the fluid can flow or flow. Examples of suitable pour point depressants include polymethacrylates, polyacrylates, polyarylamides, condensation products of haloparaffin waxes and aromatic compounds, terpolymers of vinyl carboxylate polymers and dialkylfumarates, vinyls of fatty acids and allyl vinyl ethers Contains esters. U.S. Patent Nos. 1,815,022, 2,015,748, 2,191,498, 2,387,501, 2,655,479, 2,666,746, 2,721,877, 2,721,878, 3,250,715 disclose useful pour point depressants and / or methods for their preparation It is. Each of these documents is hereby incorporated by reference in its entirety. Such additives may be used in amounts of about 0.01 to 5% by weight, preferably about 0.01 to 1.5% by weight.

Corrosion inhibitor

Preservatives are used to reduce the decomposition of metal parts in contact with the lubricant composition. Suitable preservatives include thiadiazole. See, for example, US Pat. Nos. 2,719,125, 2,719,126, and 3,087,932, which are hereby incorporated by reference in their entirety. Such additives may be used in amounts of about 0.01 to 5% by weight, preferably about 0.01 to 1.5% by weight.

Sealing compatibility additive

Seal compatibility reagents help to inflate an elastomeric seal by causing a chemical reaction in the fluid or a physical change in the elastomer. Suitable sealing compatibility reagents for lubricating oils include organic phosphates, aromatic esters, aromatic hydrocarbons, esters (eg butylbenzyl phthalate) and polybutenyl succinic anhydride. Such additives may be used in amounts of about 0.01 to 3 weight percent, preferably about 0.01 to 2 weight percent.

Antifoam

Defoamers may be advantageously added to the lubricating oil composition. These reagents delay the formation of stable bubbles. Organosilicon compounds and organic polymers are typical antifoaming agents. For example, polysiloxanes such as silicone oils or polydimethyl siloxanes provide antifoam properties. Defoamers are commercially available and can be used in conventional small amounts with other additives such as emulsifying agents. Typically the amount of these blended additives is less than 1%, often less than 0.1%.

And antirust additives

Antirust additives (or corrosion inhibitors) are additives that protect lubricated metal surfaces against chemical attack by water or other contaminants. A wide range of these additives are commercially available, see, for example, Klamann in Lubricants and Related Products, cited above.

One type of antirust additive is a polar compound that differentially wets the metal surface to protect the metal surface with an oil film. Another type of antirust additive is introduced into the water-in-oil emulsion to absorb water so that only oil contacts the metal surface. Another type of antirust additive is chemically bonded to the metal to create a non-reactive surface. Examples of suitable additives include zinc dithiophosphate, metal phenolates, basic metal sulfonates, fatty acids and amines. Such additives may be used in amounts of about 0.01 to 5% by weight, preferably about 0.01 to 1.5% by weight.

Friction modifier

Friction modifiers are any material (s) or fluids containing such materials that can change the coefficient of friction of any lubricant. Friction modifiers or lubricant agents or oil enhancers, also known as friction reducers, and other additives that change the coefficient of friction of other lubricant base oils, formulated lubricating compositions, or functional fluids are optionally combined with the base oil or lubricant composition of the present invention. Can be effectively used. Friction modifiers that lower the coefficient of friction are particularly advantageous when combined with the base oil and lubricating oil compositions of the present invention. Friction modifiers may include metal-containing compounds or materials as well as ashless compounds or materials, or mixtures thereof. Metal-containing friction modifiers may include metal salts or metal-ligand complexes in which the metal comprises an alkali, alkaline earth metal or transition group metal. Such metal-containing friction modifiers may also have low ash content. The transition metal may include Mo, Sb, Sn, Fe, Cu, Zn and the like. The ligands are alcohols, polyols, glycerol, partial ester glycerol, thiols, carboxylates, carbamates, thiocarbamates, dithiocarbamates, phosphates, thiophosphates, dithiophosphates, amides, imides, amines, thiazoles, thiadias Other polar molecular functional groups containing an effective amount of sol, dithiazole, diazole, triazole, O, N, S or P, individually or in combination. In particular, Mo-containing compounds, in particular Mo-dithiocarbamate, Mo (DTC), Mo-dithiophosphate, Mo (DTP), Mo-amine, Mo (Am), Mo-alcolate, Mo- Alcohol-amides and the like can be particularly effective.

Ashless friction modifiers also include lubricating oil materials that contain effective amounts of polar groups, such as hydroxyl-containing hydroaryl base oils, glycerides, partial glycerides, glyceride derivatives, and the like. Polar groups in friction modifiers may include hydrocarbyl groups containing an effective amount of O, N, S, or P, individually or in combination. Other friction modifiers that may be particularly effective are, for example, salts of fatty acids (both re-containing and ashless derivatives), fatty alcohols, fatty amides, fatty esters, hydroxyl-containing carboxylates and comparable synthetic long chain hydrocarbyl acids, alcohols , Amides, esters, hydroxy carboxylates and the like. In some cases fatty organic acids, fatty amines, and sulfurized fatty acids may be used as appropriate friction modifiers.

Useful concentrations of friction modifiers may range from about 0.01 to 10 to 15 weight percent or more, more preferably about 0.1 to 5 weight percent. The concentration of molybdenum containing material is often described as the Mo metal concentration. Advantageous concentrations of Mo may be at least about 10-3000 ppm, with preferred ranges of about 20-2000 ppm, and in some cases more preferred ranges of about 30-1000 ppm. All types of friction modifiers can be used alone or in combination with the materials of the present invention. Mixtures of two or more friction modifiers or mixtures of friction modifiers with optional surface active materials are also often preferred.

Typical amount of additive

When the lubricating oil composition contains one or more of the additives mentioned above, the additive is mixed into the composition in an amount sufficient to perform the intended function. Typical amounts of such additives useful in the present invention are shown in the table below.

Most of the additives are shipped from manufacturers and used with certain amounts of base oil solvent in the formulation. Thus, the weight percentages in the table below as well as other amounts mentioned in this patent application relate to the amount of active ingredient (ie, non-solvent or non-dilution amount of the ingredient). The weight percentages mentioned below are based on the total weight of the lubricating oil composition.

Experiment

Unless otherwise specified, the kinematic viscosity at 40 ° C. or 100 ° C. is measured according to ASTM test method D445, the viscosity index is measured by ASTM test method D 2270, the pour point is measured by ASTM test method D 97, and TBN is It is measured by ASTM test method D 2896.

In the following examples the hydrocarbyl aromatic is alkylated naphthalene (primarily mono-alkylated) having a kinematic viscosity of about 4.6 cSt at 100 ° C. Primary monoalkylated naphthalenes are prepared by alkylating naphthalene with olefins consisting predominantly of 1-hexadecene.

In the examples, the following components are used in the lubricating oil composition.

All examples presented herein are intended to illustrate the invention, not to limit the compositions of the invention.

A series of industry-approved Sequence VIB fuel economy engine tests (ASTM Research Report D02-1469) were performed to determine the effect of compositional changes on fuel savings of test lubricants. Fuel economy improvement (FEI) limits for various SAE viscosity grades are given in ASTM D 4485. In Table 3, Comparative Example 3.1 is a reference engine test formulation and forms the baseline FEI values used for comparison with the Examples of the present invention. The percentage difference (positive or negative) for FEI between Comparative Example 3.1 and standard D 4485 is first calculated. Similarly, the percentage difference (positive or negative) for FEI between various candidate oils and the standard D4485 limit is calculated. Comparative Example 3.1 The degree (%) of how favorable the candidate FEI value is to the FEI value is calculated. The% of the results of the advantages for each of the candidate oils is summarized in Table 3 below.

It has been unexpectedly found that the addition of about 8-9 to about 15% of the pentaerythritol ester (PE ester) results in significantly surprising fuel economy improvement. The 9.4% mixture of these PE esters for SAE 10W-30 automotive engine oils showed a surprising 44% fuel economy improvement. This 12% mixture of these PE esters for SAE 10W-30 automotive engine oils showed a surprising 65% fuel economy improvement. The 15% mixture of PE esters for SAE 10W-30 automotive engine oils showed a remarkable 77% fuel economy improvement. It has been found that higher concentrations of these PE esters result in greater fuel economy improvements. Each of these test oils contains a hydrocarbyl aromatic base oil, and the presence of such hydrocarbyl aromatics is believed to have contributed to the preferred results obtained.

The addition of about 8% or more of the pentaerythritol ester (PE ester), optionally coupled with the addition of 2% trimethylolpropane ester, provides a much larger and more surprising fuel economy improvement of more than 25% in Sequence VIB engine testing. Turned out unexpectedly. These test oils contain hydrocarbyl aromatics, and the presence of such hydrocarbyl aromatics is believed to have contributed to the preferred results obtained.

As shown in Examples 3.2, 3.3 and 3.4 of Table 3, up to 78% fuel economy improvement was found in this combination. These advantages include from about 0 to about 20% hydrocarbyl aromatic, from about 20 to about 60% group II paraffin based raw materials and from about 0.5 to about 5% by weight pure polyisobutenyl succinimide borate ashless dispersant (0.33 to 3.3). Weight% active ingredient)-said polyisobutenyl mono and bis succinimides are prepared by reacting polyisobutenyl succinic anhydrides with amines having a PIB group of approximately 1300 Mn with amines. Preferred amounts are from about 4 to about 15% hydrocarbyl aromatic, from about 30 to about 50% group II paraffin based raw material and from about 1 to about 4% polyisobutenyl succin, when expressed in weight corresponding to the dispersant HFRR test in FIG. Imide borate ashless dispersant. Pure polyisobutenyl succinimide borate ashless dispersant is approximately 2/3 active ingredient and provides about 2% active ingredient when added to the oil blend.

Those skilled in the art will readily appreciate that this finding can be extended to any paraffinic base stock. The inventors also noted that group III based raw materials and preferably GTL or Fischer-Tropsch based raw materials can be used for this discovery. Thus, as a non-limiting descriptive sample, the inventors of the present invention have a balance of about 70% by weight Group III based raw material, about 8-9% by weight pentaerythritol derived ester and about 5-6% by weight hydrocarbyl aromatic It is noted that the performance additive package of will also achieve the same surprising fuel economy increase.

A series of industry-licensed Seasight VIB fuel economy engine tests were performed to determine the effect of compositional changes on the fuel economy of the test lubricant. In Table 4, Comparative Example 4.1 is used as a reference engine test formulation to form baseline FEI values used for subsequent calculations as described above.

Surprisingly, when a relatively high concentration of Group II / Group III type paraffinic base stock is included in the lubricating oil composition in the presence of hydrocarbyl aromatic and polyol esters, for example esters derived from trimethylolpropane, significant FEI improvement is achieved in the sequence. It was unexpectedly found in a VIB engine test. A 30% fuel economy improvement is observed using approximately 44% of this paraffinic base oil, approximately 2% trimethylolpropane ester, and approximately 5% alkylated naphthalene as the hydrocarbyl aromatic. An equally surprising fuel economy improvement of 26% was found using approximately 44% of this paraffinic base oil, approximately 2% trimethylol propane ester, and approximately 5.5% alkylated naphthalene as the hydrocarbyl aromatic. These advantages include about 3 to about 30% hydrocarbyl aromatic, about 40 to about 90% paraffin base oil and about 1 to about 20% by weight trimethylolpropane ester, preferably about 4 to about 20% hydrocarbyl. Achieve maximum when using aromatics, at least about 40% paraffin base oil and about 2 to about 10% trimethylolpropane esters. These engine tests clearly demonstrate the benefits of formulations that improve this fuel economy.

The fuel economy advantage is that the Group II / III paraffinic raw materials in the finish blended lubricating oil are from about 1 to about 10% of any conventional polyol ester and / or hydrocarbyl aromatics such as alkyl naphthalene and / or other co-base oils. It is thought to be further improved when used in the presence of the above.

Those skilled in the art will readily recognize that this finding may extend to any paraffinic base stock. The inventors also noted that group III based raw materials and preferably GTL or Fischer-Tropsch based raw materials can be used for this discovery. Thus, as a non-limiting descriptive sample, the inventors of the present invention found that about 40 wt% Group III based raw materials, about 30 to 35 wt% PAO, about 2 wt% trimethylolpropane and about 4 to 6 wt% hydro It was noted that mixtures of carbyl aromatics and the remaining performance additive packages would also achieve the same surprising fuel economy increase.

When certain amorphous olefin copolymers are formulated with lubricating oils, especially lubricating oils containing significant amounts of Group II or III base oils having a viscosity index of at least about 110 to about 150, it is expected to provide an unexpected significant fuel economy improvement (friction reduction) advantage. Turned out. A series of industry-licensed Seasight VIB fuel saving engine tests were performed to determine the effect of compositional changes on the fuel economy of the test lubricant. Comparative Example 5.1 is a reference engine test formulation and forms the baseline FEI values used in subsequent calculations as described above.

Surprisingly, adding 5% amorphous olefin copolymer to blended oils blended with polyalpha olefin based raw materials derived from mixed Group II / Group III and decene-type olefins resulted in fuel economy improvements of 26% to 38% in Sequence VIB engine testing. It turned out to be amazing. These results clearly demonstrate the unexpected fuel economy improvement benefits of such formulations comprising from about 1 to about 20%, preferably from about 2 to about 15%, most preferably from about 3 to about 10% of an amorphous olefin copolymer. .

The inventors have found that the amorphous olefin copolymer is used in the presence of about 1 to about 10% or more of hydrocarbyl aromatics and / or other co-base oils such as any conventional polyol esters and / or alkyl naphthalenes in the finish blended lubricating oil. When it was discovered that fuel economy advantages could be further improved.

Those skilled in the art will readily appreciate that this finding can be extended to any paraffinic base stock. The inventors also noted that group III based raw materials and preferably GTL or Fischer-Tropsch based raw materials can be used for this discovery. Thus, as a non-limiting descriptive sample, the inventors of the present invention found that about 30% by weight Group III based raw material, about 40% by weight PAO, about 2% by weight trimethylolpropane and about 4-10% by weight hydrocarbyl aromatic It was noted that the mixture and the remaining performance additive packages will also achieve the same surprising fuel economy increase.

Sequence VIB engine testing was carried out using moderate concentrations of hydrocarbyl aromatics in the presence of at least small amounts of Group II or Group III, or in the presence of hydrolyzed and / or hydrotreated base stock (including wax isomerate base oils). It has been found that fuel economy improvements can be obtained. The presence of certain ashless dispersants may also contribute significantly to the observed fuel economy improvement. A series of industry-licensed Seasight VIB fuel economy engine tests were performed to determine the effect of compositional changes on the fuel economy of the test lubricant. Comparative Example 6.1 forms baseline FEI values that are used as reference engine test formulations and used in subsequent calculations as described above.

Surprisingly, it has been found that the use of certain paraffin based raw materials in the presence of moderate concentrations of hydrocarbyl aromatics and preferably certain polyisobutenyl succinimide borate ashless dispersants improves fuel economy. As shown in Examples 6.2, 6.3 and 6.4 of Table 6, up to 77% fuel economy improvement was found in this formulation. This advantage is at maximum using about 0 to about 20% hydrocarbyl aromatic, about 20 to about 60% group II paraffin based raw materials and about 0.5 to about 5% by weight polyisobutenyl succinimide borate ashless dispersant. Different. Preferred amounts are from about 4 to about 15% hydrocarbyl aromatic, from about 30 to about 50% group II paraffin based raw material and from about 1 to about 4 weight percent polyisobutenyl succine, corresponding to the HFRR test of the dispersant in FIG. Mid borate ashless dispersant (expressed by weight). Sequence VIB fuel economy engine test results clearly demonstrate the unexpected advantages that can be obtained using the components of the present invention.

Those skilled in the art will readily appreciate that this finding can be extended to any paraffinic base stock. The inventors also noted that group III based raw materials and preferably GTL or Fischer-Tropsch based raw materials can be used for this discovery. Thus, as a non-limiting descriptive sample, the inventors of the present invention found that about 30% by weight Group III based raw material, about 30-40% PAO, about 2% trimethylolpropane and about 5-40% hydrocarbyl Note that the mixture of aromatics and the remaining performance additive packages will also achieve the same surprising fuel economy increase.

All US patents, non-US patents and patent applications and non-patent literature cited herein are incorporated by reference in their entirety.

Claims (10)

A lubricating oil composition comprising a mixture of about 3 to about 30 weight percent pentaerythritol ester in the base stock and containing more than about 18 weight percent saturation, wherein the percentage is based on the total lubricating oil composition. The method of claim 1, A lubricating oil composition containing at least 20% by weight (based on the total lubricating oil composition) of a base material having a saturation of 90% or more. The method of claim 1, Lubricating oil composition wherein the base material is a gas-to-liquid (GTL) base material. The method of claim 1, A lubricating oil composition comprising at least one triol ester. The method of claim 4, wherein Lubricating oil composition wherein the base material comprises at least 90% saturates. The method according to claim 4 or 5, A lubricating oil composition wherein said triol ester is provided at least about 2% by weight. The method of claim 6, Lubricating oil composition wherein the base material is a GTL base material. The method of claim 1, A lubricating oil composition comprising hydrocarbyl-substituted succinimide borate salts, wherein the hydrocarbyl group has a Mn of about 1000 to about 5000. The method of claim 8, Wherein the polyisobutenyl succinimide borate is present in about 0.3% to about 3.3% by weight activity. The method of claim 9, Lubricating oil composition wherein the isobutenyl succinimide borate comprises both mono and bis succinimide.