US20080090742A1

US20080090742A1 - Compound and method of making the compound

Info

Publication number: US20080090742A1
Application number: US11/548,915
Authority: US
Inventors: Naresh C. Mathur
Original assignee: Afton Chemical Corp
Current assignee: Afton Chemical Corp
Priority date: 2006-10-12
Filing date: 2006-10-12
Publication date: 2008-04-17
Also published as: GB0718303D0; DE102007045657A1; FR2907450B1; GB2442841B; GB2442841A; FR2907450A1

Abstract

The present application is directed to compounds that are the reaction product of (i) a polyacrylate, (ii) a hindered phenol, (iii) a diaryldiamine and optionally (iv) an alkyl amine. Methods for making these compounds and formulations employing the compounds are also disclosed.

Description

FIELD OF THE DISCLOSURE

The present application is directed to novel compounds, processes for making the compounds, and compositions that comprise the compounds.

BACKGROUND OF THE DISCLOSURE

Lubricating oils as used in the internal combustion engines and transmissions of automobiles or trucks are subjected to a demanding environment during use. This environment results in the oil suffering oxidation which is catalyzed by the presence of impurities in the oil, such as iron compounds, and is also promoted by the elevated temperatures of the oil during use.
The oxidation of lubricating oils during use is often controlled to some extent by the use of antioxidant additives. Antioxidant additives can extend the useful life of the lubricating oil by, for example, reducing or preventing unacceptable viscosity increases.
A combination of antioxidants are often employed in lubricants. One such combination includes both hindered phenol compounds and alkylated diphenylamines as antioxidants. These antioxidants are believed to work synergistically by converting relatively reactive alkoxy and/or alkyl radicals to less reactive phenoxy radicals.

SUMMARY OF THE DISCLOSURE

In accordance with the disclosure, one aspect of the present application is directed to a compound that is the reaction product of (i) a polyacrylate, (ii) a hindered phenol, (iii) a diaryldiamine and optionally (iv) an alkyl amine.
Another aspect of the present application is directed to a compound of formula V

- where Y is a group having a formula VI,

- R¹is an aliphatic or aromatic group,
- R²is hydrogen or methyl,
- R³and R⁴are independently chosen from hydrogen or a linear or branched C₁to C₁₂alkyl group, with the proviso that at least one of R³and R⁴is a branched C₃to C₁₂alkyl group,
- R⁵is a secondary amine substituent,
- R⁶and R⁷are independently chosen from saturated or olefinically unsaturated aliphatic alkyl groups, and
- Ar and Ar′ are groups independently chosen from substituted or unsubtituted aryl groups having from 6 to 50 carbon atoms.

Another aspect of the present application is directed to a process for forming a first compound, the process comprising combining (i) a polyacrylate, (ii) a hindered phenol, (iii) a diaryldiamine and optionally (iv) an alkyl amine.
Another aspect of the present application is directed to a lubricant composition. The composition comprises a base oil; and a first compound that is the reaction product of (i) a polyacrylate, (ii) a hindered phenol, (iii) a diaryldiamine and optionally (iv) an alkyl amine.
Another aspect of the present application is directed to an additive package. The additive package comprises a diluent; and a first compound that is the reaction product of (i) a polyacrylate, (ii) a hindered phenol, (iii) a diaryldiamine and optionally (iv) an alkyl amine.
Another aspect of the present application is directed to a method for reducing the oxidation of a lubricating oil. The method comprising placing in the crankcase of an internal combustion engine a lubricating composition of the present application.
Additional aspects and advantages of the disclosure will be set forth in part in the description which follows, and can be learned by practice of the disclosure. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure, as claimed.

DESCRIPTION OF THE EMBODIMENTS

The present application is directed to compounds prepared by reacting (i) a polyacrylate, (ii) a hindered phenol, (iii) a diaryldiamine and optionally (iv) an alkyl amine. In some aspects of the present application, the resulting compounds comprise both a hindered phenol functional group and a diaryldiamine functional group. The plurality of functional groups of the compounds of the present application may result in useful properties, such as, for example, compounds having good antioxidant function and/or other capabilities, as described in more detail below.
Representative examples of suitable polyacrylates used to form the compounds of the present application include, but are not limited to, compounds of the formula I,
wherein R¹is an aliphatic group or aromatic group, R²is hydrogen or methyl and q is an integer from about 2 to about 4. Non-limiting examples of a polyacrylate suitable for use herein include trimethylolpropane triacrylate (TMPTA), hydroquinone diacrylate, hydroquinone dimethacrylate, pyrogallol diacrylate, pyrogallol dimethacrylate, pyrogallol triacrylate, resorcinol diacrylate, resorcinol dimethacrylate, glycol diacrylate, glycol dimethacrylate, glycerol diacrylate, glycerol trimethacrylate, 1,1,1-trimethylol ethane triacrylate, glucose polyacrylate, pentaerythritol tetraacrylate, pentaerythritol trimethacrylate, diethyleneglycol diacrylate, triethyleneglycol dimethacrylate, propyleneglycol diacrylate and the like.
Suitable hindered phenols for use in the present application include compounds of formula II,
wherein R³and R⁴can be independently chosen from, for example, hydrogen or a linear or branched C₁to C₁₂alkyl group, with the proviso that at least one of R³and R⁴is a branched C₃to C₁₂alkyl group. Non-limiting examples of suitable phenols include compounds chosen from 2-tert-butylphenol; 2,6-ditert-butylphenol; 2-isopropylphenol; 2,6-diisopropylphenol; 2-sec-butylphenol; 2,6 di-sec-butylphenol; 2-tert-hexylphenol; 2,6-ditert-hexylphenol; 2-tert-butyl-o-cresol; 2-tert-dodecylphenol; 2-tert-decyl-o-cresol and 2-tert-butyl-6-isopropylphenol. In one embodiment, the hindered phenol is 2,6 di-tert-butylphenol.
Suitable diaryldiamines for use in forming the compounds of the present application include reactant compounds of the formula III,
wherein Ar and Ar′ each independently represent a substituted or unsubtituted aryl group having from about 6 to about 50 carbon atoms; and wherein R⁵is an amine substituent. Non-limiting examples of suitable amines include primary amine substituents such as —NH₂, —[NH(CH₂)_n]_mNH₂, —(CH₂)_nNH₂, and —CH₂-aryl-NH₂in which n is an integer ranging from about 1 to about 20, such as from about 1 to about 10, or in another embodiment, from about 2 to about 4; and m is an integer having a value of from about 1 to about 20, such as from about 2 to about 10. Non-limiting examples of other substituents that can also be bonded to Ar and Ar′ in addition to the R⁵substituent include one or more additional primary amine substituents, such as those listed above for R⁵; aliphatic hydrocarbon groups, such as alkyl groups having from about 1 to about 20 carbon atoms; hydroxyl; carboxyl and nitro groups. In some embodiments, both Ar and Ar′ can be phenyl groups. For example, the diaryldiamine can be an N-phenylphenylenediamine (NPPDA), such as N-phenyl-1,3-phenylenediamine, N-phenyl-1,2-phenylenediamine and N-phenyl-1,4-phenylenediamine.
Any suitable alkyl amines can optionally be included as reactants in the present application. When included, the alkyl amines can provide increased solubility of the resulting compounds. In some embodiments, suitable alkyl amines can include secondary amines of formula IV,

- where R⁶and R⁷are independently chose, saturated or olefinically unsaturated aliphatic alkyl groups. For example, R⁶and R⁷can be C₁-C₃₀alkyl groups. Representative examples of such secondary amines include, but are not limited to, di-iso-amylamine, di-n-octylamine, di-(2ethylhexyl)amine, di-(tert-octyl)amine, di-n-nonylamine, dilauryl amine, di-hexadecylamine, di-octadecylamine, and di-oleylamine. In some embodiments, primary amines can be employed, such as n-octylamine, 2-ethylhexylamine, tert-octylamine, n-decylamine, n-undecylamine, lauryl amine. hexadecylamine, heptadecylamine, octadecylamine, decenylamine, dodecenylamine, palmitoleylamine, oleylamine, linoleylamine, and eicosenylamine.

The above described reactant compounds can be employed to produce the product compounds of the present application. The product compounds of the present application can be compounds of general formula V,
where Y is the acrylate or methacrylate group of the polyacrylate of formula I above, the Y group having a formula VI,
and where ′R⁵is an amine formed by bonding the R⁵amine with a Y group of the polyacrylate of formula I, and R¹, R², R³, R⁴, R⁶, R⁷, Ar and Ar′ are defined as set forth above. Suitable examples of ′R⁵amine substituents include —NH—, —[NH(CH₂)_n—]_m—NH—, —(CH₂)_n—NH—, and —CH₂aryl—NH— in which n and m are as defined above.
In one embodiment, the product compound can have the formula VII,
where Y, R⁶and R⁷are defined as above.
The process of reacting the reactant compounds described above can be performed in any suitable manner which will produce the desired product compounds of the present application. During the reaction, the vinyl group double bonds of the polyacrylate can react with the hindered phenol, diaryldiamine and the alkyl amine reactant compounds to form the desired product compounds.
Any suitable concentrations of the above reactant compounds can be mixed together and reacted under suitable conditions that will result in the compounds of the present application. For example, reactants can be combined in ratios ranging from about a 1:x:y:z molar ratio of polyacrylate, hindered phenol, diaryldiamine and alkyl amine, where x and y can range from about 1 to about 4; and z can range from 0 to about 2. Suitable reaction temperatures and concentrations of reactants employed in forming the compounds of the present application can be determined by one of ordinary skill in the art.
In one embodiment, the process can include mixing suitable amounts of all the ingredients, including the polyacrylate, hindered phenol, diaryldiamine and the alkyl amine reactant compounds under conditions which result in a reaction to form the desired product compounds. In other embodiments, the reactant compounds can be reacted in a stepwise manner.
In stepwise reaction processes, the diaryldiamine, hindered phenol, and alkyl amine can be combined with the polyacrylate in any order to form the product of Formula V, as illustrated below. For example, the polyacrylate can be reacted with the diaryldiamine to form a first intermediate product; followed by providing and reacting the hindered phenol with the first intermediate product to form a second intermediate product; and then combining and reacting the alkyl amine with the second intermediate product to form the final product of formula V above. In another example, the polyacrylate can be reacted with the alkyl amine to form a first intermediate product; followed by combining and reacting the hindered phenol with the first intermediate product to form a second intermediate product; and then combining and reacting the diaryldiamine with the second intermediate product to form the final product of formula V above.
The compounds of the present application may have many uses. For example, the compounds may be useful as antioxidants, anti-knocking agents, and/or as performance enhanced additives useful for improving or maintaining viscosity, or reducing discoloration and/or sludge or deposit formation in a variety of formulations, such as lubricant compositions, fuel compositions, or plastics. Other related applications may also be readily apparent to one of ordinary skill in the art.
The lubricating compositions disclosed herein can comprise a base oil. Base oils suitable for use in formulating the disclosed compositions can be selected from, for example, synthetic or mineral oils, or mixtures thereof.
The base oil can be present in a major amount, wherein “major amount” is understood to mean greater than or equal to 50% by weight of the lubricant composition, such as from about 80% to about 98% by weight of the lubricant composition. The base oil typically has a viscosity of, for example, from about 2 to about 15 cSt and, as a further example, from about 2 to about 10 cSt at 100° C.
Non-limiting examples of mineral oils suitable as base oils include animal oils and vegetable oils (e.g., caster oil, lard oil) as well as other mineral lubricating oils such as liquid petroleum oils and solvent treated or acid-treated mineral lubricating oils of the paraffinic, naphthenic or mixed paraffinic-naphthenic types. Oils derived from coal or shale are also suitable. Further, oils derived from a gas-to-liquid process are also suitable.
Non-limiting examples of synthetic oils include hydrocarbon oils such as polymerized and interpolymerized olefins (e.g., polybutylenes, polypropylenes, propylene isobutylene copolymers, etc.): polyalphaolefins such as poly(1-hexenes), poly-(1-octenes), poly(1-decenes), etc. and mixtures thereof: alkylbenzenes (e.g., dodecylbenzenes, tetradecylbenzenes, di-nonylbenzenes, di-(2-ethylhexyl)benzenes, etc.); polyphenyls (e.g., biphenyls, terphenyl, alkylated polyphenyls, etc.); alkylated diphenyl ethers and alkylated diphenyl sulfides and the derivatives, analogs and homologs thereof and the like.
Alkylene oxide polymers and interpolymers and derivatives thereof where the terminal hydroxyl groups have been modified by esterification, etherification, etc., constitute another class of known synthetic oils that can be used. Such oils are exemplified by the oils prepared through polymerization of ethylene oxide or propylene oxide, the alkyl and aryl ethers of these polyoxyalkylene polymers (e.g., methyl-polyisopropylene glycol ether having an average molecular weight of about 1000, diphenyl ether of polyethylene glycol having a molecular weight of about 500-1000, diethyl ether of polypropylene glycol having a molecular weight of about 1000-1500, etc.) or mono- and polycarboxylic esters thereof, for example, the acetic acid esters, mixed C_3-8fatty acid esters, or the C₁₅Oxo acid diester of tetraethlene glycol.
Another class of synthetic oils that can be used includes the esters of dicarboxylic acids (e.g., phthalic acid, succinic acid, alkyl succinic acids, alkenyl succinic acids, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid dimer, malonic acid, alkyl malonic acids, alkenyl malonic acids, etc.) with a variety of alcohols (e.g., butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene glycol, etc.) Specific examples of these esters include dibutyl adipate, di(2-ethylhexyl)sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, didecyl phthalate, dieicosyl sebacate, the 2-ethylhexyl diester of linoleic acid dimer, the complex ester formed by reacting one mole of sebacic acid with two moles of tetraethylene glycol and two moles of 2-ethylhexanoic acid and the like.
Esters useful as synthetic oils also include those made from C_5-12monocarboxylic acids and polyols and polyol ethers such as neopentyl glycol, trimethylol propane, pentaerythritol, dipentaerythritol, tripentaerythritol, etc.
Hence, the base oil used to make the compositions as described herein can be selected from any of the base oils in Groups I-V as specified in the American Petroleum Institute (API) Base Oil Interchangeability Guidelines. Such base oil groups are as follows:
Group I contain less than 90% saturates and/or greater than 0.03% sulfur and have a viscosity index greater than or equal to 80 and less than 120; Group II contain greater than or equal to 90% saturates and less than or equal to 0.03% sulfur and have a viscosity index greater than or equal to 80 and less than 120; Group III contain greater than or equal to 90% saturates and less than or equal to 0.03% sulfur and have a viscosity index greater than or equal to 120; Group IV are polyalphaolefins (PAO); and Group V include all other basestocks not included in Group I, II, III or IV.
The test methods used in defining the above groups are ASTM D2007 for saturates; ASTM D2270 for viscosity index; and one of ASTM D2622, 4294, 4927 and 3120 for sulfur.
Group IV basestocks, i.e. polyalphaolefins (PAO) include hydrogenated oligomers of an alpha-olefin, the most important methods of oligomerisation being free radical processes, Ziegler catalysis, and cationic, Friedel-Crafts catalysis.
The polyalphaolefins typically have viscosities in the range f 2 to 100 cSt at 100° C., for example 4 to 8 cSt at 100° C. They can, for example, be oligomers of branched or straight chain alpha-olefins having from about 2 to about 30 carbon atoms; non-limiting examples include polypropenes, polyisobutenes, poly-1-butenes, poly-1-hexenes, poly-1-octenes and poly-1-decene. Included are homopolymers, interpolymers and mixtures.
Regarding the balance of the basestock referred to above, a “Group I basestock” also includes a Group I basestock with which basestock(s) from one or more other groups can be admixed, provided that the resulting admixture has characteristics falling within those specified above for Group I basestocks.
Exemplary basestocks include Group I basestocks and mixtures of Group II basestocks with Group I basestock.
Basestocks suitable for use herein can be made using a variety of different processes including but not limited to distillation, solvent refining, hydrogen processing, oligomerisation, esterification, and re-refining.
The base oil can be an oil derived from Fischer-Tropsch synthesized hydrocarbons. Fischer-Tropsch synthesized hydrocarbons can be made from synthesis gas containing H₂and CO using a Fischer-Tropsch catalyst. Such hydrocarbons typically require further processing in order to be useful as the base oil. For example, the hydrocarbons can be hydroisomerized using processes disclosed in U.S. Pat. Nos. 6,103,099 or 6,180,575; hydrocracked and hydroisomerized using processes disclosed in U.S. Pat. Nos. 4,943,672 or 6,096,940; dewaxed using processes disclosed in U.S. Pat. No. 5,882,505; or hydroisomerized and dewaxed using processes disclosed in U.S. Pat. Nos. 6,013,171; 6,080,301; or 6,165,949.
Unrefined, refined and rerefined oils, either mineral or synthetic (as well as mixtures of two or more of any of these) of the type disclosed hereinabove can be used in the base oils. Unrefined oils are those obtained directly from a mineral or synthetic source without further purification treatment. For example, a shale oil obtained directly from retorting operations, a petroleum oil obtained directly from primary distillation or ester oil obtained directly from an esterification process and used without further treatment would be an unrefined oil. Refined oils are similar to the unrefined oils except they have been further treated in one or more purification steps to improve one or more properties. Many such purification techniques are known to those skilled in the art such as solvent extraction, secondary distillation, acid or base extraction, filtration, percolation, etc. Rerefined oils are obtained by processes similar to those used to obtain refined oils, where the processes are applied to refined oils which have been already used in service. Such rerefined oils are also known as reclaimed or reprocessed oils and often are additionally processed by techniques direceted to removal of spent additives, contaminants, and oil breakdown products.
The lubricant compositions of the present application can be used in any engine or other combustion systems or mechanical devices that may benefit therefrom. For example, the lubricant compositions can be suitable for use in the crank case of an internal combustion engine.
The product compounds of the present application can be included in a lubricant composition in an amount sufficient to improve the antioxidant property of the lubricant. For example, an amount ranging from about 0.05 to about 10 weight percent, such as from about 0.1 to about 4 weight percent, relative to the total amount of the lubricant composition is usually sufficient.
In some embodiments, the compounds of the present application can be added to the oil in the form of a concentrate additive composition. These are concentrates dissolved in a diluent, such as mineral oil, synthetic hydrocarbon oils, and mixtures thereof. When combined to the base oil, the concentrate additive composition can provide an effective concentration of the additives in the base oil. The amount of the compounds of the present application in the additive package can vary from about 5 wt % to about 75 wt % of the additive composition, such as from about 10 wt % to about 50 wt.
The additive composition and finished lubricant composition of the present application can contain other additional additives. Examples of such additional additives include dispersants, detergents, anti-wear agents, supplemental antioxidants, viscosity index improvers, pour point depressants, corrosion inhibitors, rust inhibitors, foam inhibitors, anti-swell agents and friction modifiers. Such additives are well known in the art, and choosing effective amounts of additional additives in lubricant compositions would be within the ordinary skill of the art.
The following examples are presented to illustrate the manner in which the additives of the invention can be prepared and are not to be considered as limiting as to any aspect thereof.

EXAMPLES

Example 1

Method of Making a Compound

An exemplary process for making an compound of the present application was carried out as follows:
Step 1: A 1-liter 4-neck flask equipped with nitrogen sub-surface was charged with 236.8 g of trimethylolpropane triacrylate (TMPTA), 300 g methanol, and 0.8 g of laural mercaptan. To this solution 192.8 g of bis(2-ethylhexylamine) was added dropwise over 4 hr period and then allowed to stir at room temperature for 3 hrs. The temperature was then raised to 65° C. to distill methanol and finally vacuum stripped and filtered over Celite. A total of approximately 424 g of product was isolated. % N=2.74%
Step 2: A 500 mL flask was charged with 149 g of process oil, 64 g of 2,6-di-tert butylphenol and 1 g of potassium hydroxide. The mixture was heated to about 120° C. and then mild vacuum was applied to remove about 1.3 ml of distillate. Vacuum was removed and the mixture was then heated to 140° C. 161 g of the product isolated from step 1 was then added dropwise over a 2-3 hr period. After the addition was complete, the reaction was held at 140° C. for 3 hrs and 8 g of talc was added and stirred for 30 min. The mixture was then filtered over Celite. A total of approximately 235 g of product was obtained. % N=1.27; TBN=47.2
Step 3: 127.3 g of the product obtained from step 2 and 240 ml of butanol were chared to a 500 ml flask and equipped with nitrogen sub-surface and condenser. The mixture was heasted to about 80° C. and 9.2 g of N-phenylphenylenediamine (NPPDA) was added all at once. The temperature was raised to 120° C. and held for approximately 10 hrs. Butanol was removed under vacuum. The product thus obtained was diluted with 34.7 g of process oil, allowed to cool to room temperature overnght and then filtered over Celite. % N=1.43; TBN=47. The resulting product was tested as an antioxidant as described in Example 3 below.

EXAMPLE 2

Method of Making an Compound

Another exemplary process for making a compound of the present application was carried out as follows.
A 500 ml flask was charged with 74 g of TMPTA and 240 g of butanol. The flask was equipped with nitrogen sub-surface and reflux condenser and heated to about 80° C. 46 g of NPPDA was added in portions over 30 min and the mixture was then heated to reflux for 8 hrs. 51.5 g of 2,6-di-tert butylphenol and 0.7 g potassium hydroxide were added and the mixture was again held at reflux for 7 hrs. The reflux condenser was replaced with a distillation apparatus and the mixture was heated to 145° C., during which almost 200 ml butanol was removed. The mixture was cooled to 65° C. and 60.3 g of bis(2-ethylhexyl)amine was added dropwise over a 2 hr period. The mixture was held at 65° C. for 3 hrs and then vacuum stripped. 7 g of talc was added and stirred for 30 minutes, followed by filteration through paper to remove solids. The filtered product had 4.22% N and had a TBN of 131.

EXAMPLE 3

Evaluation of Engine Oils Containing the Compound of Example 1 in the Thermo-Oxidation Engine Oil Simulation Test (TEOST MHT-4)

The TEOST MHT-4 is a standard lubricant industry test for the evaluation of the oxidation and carbonaceous deposit-forming characteristics of engine oils. The test is designed to simulate high temperature deposit formation in the piston ring belt area of modern engines. The test utilizes a patented instrument (U.S. Pat. No. 5,401,661 and U.S. Pat. No. 5,287,731; the disclosure of each patent is hereby incorporated by reference in its entirety) with the MHT-4 protocol being a relatively new modification to the test. Details of the test operation and specific MHT-4 conditions have been published by Selby and Florkowski (Selby et al.) in a paper entitled, “The Development of the TEOST Protocol MHT as a Bench Test of Engine Oil Piston Deposit Tendency” presented at the 12th International Colloquium Technische Akademie Esslingen, Jan. 11-13, 2000. Wilfried J. Bartz editor. The Selby et al. paper is hereby incorporated by reference in its entirety.
Oil Blends A, B, and C were evaluated using the TEOST MHT-4 with the results shown in the attached Table 1. Blend A was the baseline to which 0.5 and 1 wt % of the compound of Example 1 were combined to make blends B and C, respectively.

TABLE 1

Blend A	Blend B	Blend C

Core Pack “A” of	90	90	90
additives
Alkylated	0.8	0.8	0.8
diphenylamines
Compound of	0	0.5	1.0
Example 1
Motiva 5 cst base	9.2	8.7	8.2
stock
Total wt %	100	100	100
TEOST (MHT-4),	38	23.7	16
mg

As shown in Table I above, blends B and C showed lower deposits (in mg) than blend A. These results demonstrate improved antioxidant performance from the compound of Example 1, as compared with blend A, which did not contain a compound of the present application.
For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing quantities, percentages or proportions, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
It is noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the,” include plural referents unless expressly and unequivocally limited to one referent. Thus, for example, reference to “an acid” includes two or more different acids. As used herein, the term “include” and its grammatical variants are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that can be substituted or added to the listed items.
While particular embodiments have been described alternatives, modifications, variations, improvements, and substantial equivalents that are or can be presently unforseen can arise to applicants or others skilled in the art. Accordingly, the appended claims as filed and as they can be amended are intended to embrace all such alternatives, modifications variations, improvements, and substantial equivalents.

Claims

1. A compound that is the reaction product of (i) a polyacrylate, (ii) a hindered phenol, (iii) a diaryldiamine and optionally (iv) an alkyl amine.

2. The compound of claim 1, wherein the polyacrylate is a compound of the formula I,

where R¹is an aliphatic or aromatic group, R²is hydrogen or methyl and q is an integer from about 2 to about 4.

3. The compound of claim 1, wherein the polyacrylate is a compound chosen from trimethylolpropane triacrylate (TMPTA), hydroquinone diacrylate, hydroquinone dimethacrylate, pyrogallol diacrylate, pyrogallol dimethacrylate, pyrogallol triacrylate, resorcinol diacrylate, resorcinol dimethacrylate, glycol diacrylate, glycol dimethacrylate, glycerol diacrylate, glycerol trimethacrylate, 1,1,1-trimethylol ethane triacrylate, glucose polyacrylate, pentaerythritol tetraacrylate, pentaerythritol trimethacrylate, diethyleneglycol diacrylate, triethyleneglycol dimethacrylate, and propyleneglycol diacrylate.

4. The compound of claim 1, wherein the hindered phenol is a compound of the formula II,

where R³and R⁴are independently chosen from hydrogen or a linear or branched C₁to C₁₂alkyl group, with the proviso that at least one of R³and R⁴is a branched C₃to C₁₂alkyl group.

5. The compound of claim 1, wherein the hindered phenol is a compound chosen from 2-tert-butylphenol; 2,6-ditert-butylphenol; 2-isopropylphenol; 2,6-diisopropylphenol; 2-sec-butylphenol; 2,6 di-sec-butylphenol; 2-tert-hexylphenol; 2,6-ditert-hexylphenol; 2-tert-butyl-o-cresol; 2-tert-dodecylphenol; 2-tert-decyl-o-cresol and 2-tert-butyl-6-isopropylphenol.

6. The compound of claim 1, wherein the hindered phenol is 2,6 di-tert butyl phenol.

7. The compound of claim 1, wherein the diaryldiamine is a compound of the formula III,

where Ar and Ar′ each independently represent a substituted or unsubtituted aryl group having from about 6 to about 50 carbon atoms; and

R⁵is an amine substituent.

8. The compound of claim 7, wherein R₅is a substituent chosen from —NH₂, —[NH(CH₂)_n]_mNH₂, —(CH₂)_nNH₂, and —CH₂-aryl-NH₂, in which n and m are each an integer having a value of from about 1 to about 10.

9. The compound of claim 7, wherein at least one of Ar and Ar′ is substituted with one or more substituents in addition to R₅, the one or more additional substituents being chosen from primary amine substituents, aliphatic hydrocarbon groups, hydroxyl groups, carboxyl groups, and nitro groups.

10. The compound of claim 7, wherein Ar and Ar′ are phenyl groups.

11. The compound of claim 1, wherein the diaryldiamine is a compound chosen from N-phenyl-1,3-phenylenediamine, N-phenyl-1,2-phenylenediamine, and N-phenyl-1,4-phenylenediamine.

12. The compound of claim 1, wherein the compound is the reaction product of (i), (ii), (iii) and (iv), the alkyl amine being a compound of the formula IV,

where R⁵and R⁷are substituents independently chosen from hydrogen and saturated or olefinically unsaturated aliphatic alkyl groups, with the proviso that at least one of R⁵and R⁷is not hydrogen.

13. The compound of claim 1, wherein the compound is the reaction product of (i), (ii), (iii) and (iv), the alkyl amine being a compound chosen from di-iso-amylamine, di-n-octylamine, di-(2ethylhexyl)amine, di-(tert-octyl)amine, di-n-nonylamine, dilauryl amine, di-hexadecylamine, di-octadecylamine, di-oleylamine; n-octylamine, 2-ethylhexylamine, tert-octylamine, n-decylamine, n-undecylamine, lauryl amine, hexadecylamine, heptadecylamine, octadecylamine, decenylamine, dodecenylamine, palmitoleylamine, oleylamine, linoleylamine, and eicosenylamine.

14. A compound of formula V,

where Y is a group having a formula VI,

R¹is an aliphatic or aromatic group,

R²is hydrogen or methyl,

R³and R⁴are independently chosen from hydrogen or a linear or branched C₁to C₁₂alkyl group, with the proviso that at least one of R³and R⁴is a branched C₃to C₁₂alkyl group,

′R⁵is a secondary amine substituent;

R⁶and R⁷are independently chosen from saturated or olefinically unsaturated aliphatic alkyl groups, and

Ar and Ar′ are groups independently chosen from substituted or unsubtituted aryl groups having from 6 to 50 carbon atoms.

15. A process for forming a first compound, the process comprising combining (i) a polycrylate, (ii) a hindered phenol, (iii) a diaryldiamine and optionally (iv) an alkyl amine.

16. The process of claim 15, wherein:

the polyacrylate is a compound of the formula I,

where R¹is an aliphatic or aromatic group, R²is hydrogen or methyl and q is an integer from 2 to 4;

the hindered phenol is a compound of the formula II,

where R³and R⁴are independently chosen from hydrogen or a linear or branched C₁to C₁₂alkyl group, with the proviso that at least one of R³and R⁴is a branched C₃to C₁₂alkyl group; and

the diaryldiamine is a compound of the formula III,

where Ar and Ar′ each independently represent a substituted or unsubituted aryl group having from 6 to 50 carbon atoms, and R⁵is an amine substituent.

17. The process of claim 16, wherein the first compound is prepared by combining the alkyl amine with (i), (ii) and (iii), the alkyl amine being a compound of the formula IV,

where R⁶and R⁷are substituents independently chosen from hydrogen and saturated or olefinically unsaturated aliphatic alkyl groups, with the proviso that at least one of R⁶and R⁷is not hydrogen.

18. A lubricant composition comprising:

a base oil; and

a first compound that is the reaction product of (i) a polyacrylate, (ii) a hindered phenol, (iii) a diaryldiamine and optionally (iv) an alkyl amine.

19. The lubricant composition of claim 18, wherein the concentration of the compound ranges from about 0.05 wt % to about 10 wt % of the lubricant composition.

20. The lubricant composition of claim 18, further comprising one or more additional additives chosen from dispersants, detergents, anti-wear agents, supplemental antioxidants, viscosity index improvers, pour point depressants, corrosion inhibitors, rust inhibitors, foam inhibitors, anti-swell agents and friction modifiers.

21. The lubricant of claim 18, wherein:

the polyacrylate is a compound of the formula I,

where R¹is an aliphatic or aromatic group, R²is hydrogen or methyl and q is an integer from about 2 to about 4;

the hindered phenol is a compound of the formula II,

where R³and R⁴are independently chosen from hydrogen or a linear or branched C₁to C₁₂alkyl group, with the proviso that at least one of R⁵and R⁴is a branched C₃to C₁₂alkyl group; and

the diaryldiamine is a compound of the formula III,

where Ar and Ar′ each independently represent a substituted or unsubstituted aryl group having from about 6 to about 50 carbon atoms; and

R⁵is an amine substituent.

22. The lubricant of claim 21, wherein R₅is a substituent chosen from —NH₂, —[NH(CH₂)_n]_mNH₂, —(CH₂)_nNH₂, and —CH₂-aryl-NH₂in which n and m are each an integer having a value of from about 1 to about 10.

23. The lubricant of claim 22, wherein Ar and Ar′ are phenyl groups.

24. The lubricant of claim 21, wherein the first compound that is the reaction product of (i), (ii), (iii), and (iv), the alkyl amine being a compound of the formula IV,

25. The lubricant of claim 18, wherein:

the polyacrylate is a compound chosen from trimethylolpropane triacrylate (TMPTA), hydroquinone diacrylate, hydroquinone dimethacrylate, pyrogallol diacrylate, pyrogallol dimethacrylate, pyrogallol triacrylate, resorcinol diacrylate, resorcinol dimethacrylate, glycol diacrylate, glycol dimethacrylate, glycerol diacrylate, glycerol trimethacrylate, 1,1,1-trimethylol ethane triacrylate, glucose polyacrylate, pentaerythritol tetraacrylate, pentaerythritol trimethacrylate, diethyleneglycol diacrylate, triethyleneglycol dimethacrylate, and propyleneglycol diacrylate;

the hindered phenol is a compound chosen from 2-tert-butylphenol; 2,6-ditert-butylphenol; 2-isopropylphenol; 2,6-diisopropylphenol; 2-sec-butylphenol; 2,6 di-sec-butylphenol; 2-tert-hexylphenol; 2,6-ditert-hexylphenol; 2-tert-butyl-o-cresol; 2-tert-dodecylphenol; 2-tert-decyl-o-cresol and 2-tert-butyl-6-isopropylphenol; and

the diaryldiamine is a compound chosen from N-phenyl-1,3-phenylenediamine, N-phenyl-1,2-phenylenediamine, and N-phenyl-1,4-phenylenediamine.

26. The lubricant of claim 25, wherein the first compound is the reaction product of (i), (ii), (iii) and (iv), the alkyl amine being a compound chosen from di-iso-amylamine, di-n-octylamine, di-(2ethylhexyl)amine, di-(tert-octyl)amine, di-n-nonylamine, dilauryl amine, di-hexadecylamine, di-octadecylamine, di-oleylamine; n-octylamine, 2-ethylhexylamine, tert-octylamine, n-decylamine, n-undecylamine, lauryl amine, hexadecylamine, heptadecylamine, octadecylamine, decenylamine, dodecenylamine, palmitoleylamine, oleylamine, linoleylamine, and eicosenylamine.

27. The lubricant of claim 25, wherein:

the polyacrylate is TMPTA;

the hindered phenol is 2,6 di-tert butyl phenol; and

28. A lubricant composition comprising:

a base oil; and

the compound of claim 14.

29. An additive package comprising:

a diluent; and

30. The additive package of claim 29, wherein the concentration of the compound ranges from about 5 wt % to about 75 wt % of the additive package.

31. The additive package composition of claim 29, further comprising one or more additional additives chosen from dispersants, detergents, anti-wear agents, supplemental antioxidants, viscosity index improvers, pour point depressants, corrosion inhibitors, rust inhibitors, foam inhibitors, anti-swell agents and friction modifiers.

32. The additive package of claim 29, wherein:

the polyacrylate is a compound of the formula I,

the hindered phenol is a compound of the formula II,

the diaryldiamine is a compound of the formula III,

R⁵is an amine substituent.

33. The additive package of claim 32, wherein R₅is a substituent chosen from —NH₂, —[NH(CH₂)_n]_mNH₂, —(CH₂)_nNH₂, and —CH₂-aryl-NH₂in which n and m are each an integer having a value of from about 1 to about 10.

34. The additive package of claim 33, wherein Ar and Ar′ are phenyl groups.

35. The additive package of claim 32, wherein the first compound is the reaction product of (i), (ii), (iii) and (iv), the alkyl amine being a compound of the formula IV,

36. The additive package of claim 29, wherein:

37. The additive package of claim 36, wherein the first compound is the reaction product of (i), (ii), (iii) and (iv), the alkyl amine being a compound chosen from di-iso-amylamine, di-n-octylamine, di-(2ethylhexyl)amine, di-(tert-octyl)amine, di-n-nonylamine, dilauryl amine, di-hexadecylamine, di-octadecylamine, di-oleylamine; n-octylamine, 2-ethylhexylamine, tert-octylamine, n-decylamine, n-undecylamine, lauryl amine, hexadecylamine, heptadecylamine, octadecylamine, decenylamine, dodecenylamine, palmitoleylamine, oleylamine, linoleylamine, and eicosenylamine.

38. The additive package of claim 36, wherein:

the polyacrylate is TMPTA;

the hindered phenol is 2,6 di-tert butyl phenol; and

39. A additive package composition comprising:

a base oil; and

the compound of claim 14.

40. A method for reducing the oxidation of a lubricating oil, the method comprising placing in the crankcase of an internal combustion engine a lubricating composition according to claim 18.