KR20080103588A - Lubricant oil additive compositions - Google Patents

Abstract

A lubricant oil composition having a synergistic oxidative stability is disclosed, the composition comprising at least one hindered phenolic antioxidant, at least one mono-boronated hindered phenolic antioxidant, at least one di-boronated hindered phenolic antioxidant, at least one alkylated diphenylamine and at least one organomolybdenum compound. The invention also provides a lubricating oil additive concentrate composition that imparts synergistic oxidative stability to a lubricant oil upon its addition, the concentrate composition comprising at least one hindered phenolic antioxidant, at least one mono-boronated hindered phenolic antioxidant, at least one di-boronated hindered phenolic antioxidant, at least one alkylated diphenylamine and at least one organomolybdenum compound. Further, the concentrate compositions of the present invention may also be prepared with a high concentration of hindered phenolic antioxidants without deleterious effects on viscosity or lubricant solubility.

Description

Lube oil additive composition {LUBRICANT OIL ADDITIVE COMPOSITIONS}

The present invention relates to a lubricating oil additive composition and a lubricating oil composition containing the same. More specifically, the present invention relates to a combination of hindered phenolic antioxidants, boronated hindered phenolic antioxidants, alkylated diphenylamines and organomolybdenum compounds useful as lubricating oil compositions and lubricating oil additive compositions.

Impaired phenols and boronated impaired phenols, including polymeric phenols incorporating moieties such as 2,6-di-tert-butylphenol, are well known in the art. See, for example, the following US and foreign patents: US 4,927,553; US 3,356,707; US 3,509,054; US 3,347,793; US 3,014,061; US 3,359,298; US 2,813,830; US 2,462,616; GB 864,840; US 5,698,499; US 5,252,237; US RE 32,295; US 4,547,302; US 3,211,652; And US 2,807,653.

The use of alkylated diphenylamines as antioxidant additives in lubricating oil formulations is also well known in the art. See, for example, the following US patents: US 5,620,948; US 5,595,964; US 5,569,644; US 4,857,214; US 4,455,243; And US 5,759,965.

There are many examples in the patent literature that show the use of molybdenum additives as deposition control additives, antiwear additives and friction modifiers. See, for example, the following US and foreign patents: US 5,840,672; US 5,814,587; US 4,529,526; WO 95/07966; US 5,650,381; US 4,812,246; US 5,458,807; WO 95/07964; US 5,880,073; US 5,658,862; US 5,696,065; WO 95/07963; US 5,665,684; US 4,360,438; US 5,736,491; WO 95/27022; US 5,786,307; US 4,501,678; US 5,688,748; EP 0 447 916 A1; US 5,807,813; US 4,692,256; US 5,605,880; WO 95/07962; US 5,837,657; US 4,832,867; US 4,705,641; EP 0 768 366 A1; US 6,103,674; US 6,010,987; US 6,110,878; EP 1 136 496 A1; US 6,150,309; US 6,232,276; US 6,306,802; EP 1 136 497 A1; US 5,888,945; US 6,187,723; US 6,117,826; US 6,103,674; US 6,063,741; US 6,017,858; US 5,994,277; And US 6,174,842.

Summary of the Invention

The present invention generally provides a lubricating oil composition with improved oxidative stability, which composition comprises at least one hindered phenolic antioxidant, at least one mono-boronated hindered phenolic antioxidant, at least one di-boronated hindered Phenolic antioxidants, one or more alkylated diphenylamines and one or more organomolybdenum compounds. The present invention also provides a lubricating oil-added concentrated composition which gives synergistic oxidative stability to the lubricating oil, the addition of which comprises at least one hindered phenolic antioxidant, at least one mono-boronated hindered phenolic antioxidant At least one di-boronated hindered phenolic antioxidant, at least one alkylated diphenylamine and at least one organomolybdenum compound. Additionally, the concentrated compositions of the present invention can also be prepared from high concentrations of hindered phenolic antioxidants without detrimental effects on viscosity or lubricant solubility.

Lubricating oil compositions and lubricating oil concentrate compositions (at least one hindered phenolic antioxidant, at least one mono-boronated hindered phenolic antioxidant, at least one di-boronated hindered phenolic antioxidant and at least one alkylated diphenylamine Synergistic improvements in oxidative stability in PCT Application No. PCT / claiming priority to co-owned US Provisional Application 60 / 758,754, and US Provisional Application 60 / 758,754, filed Jan. 13, 2006, US 2007/060489, both incorporated herein by reference to the extent that their entirety is permitted by patent law. In the present invention, which improves the disclosure of US Provisional Application 60 / 758,754, a lubricating oil composition and a lubricating oil concentrate composition (one or more hindered phenolic antioxidants, one or more mono-boronated hindered phenolic antioxidants, one or more de-boronated Hindered phenolic antioxidants, including one or more alkylated diphenylamines and one or more organomolybdenum compounds) exhibit improved oxidative stability compared to conventional formulations.

In one aspect, a lubricating oil or lubricating oil concentrate composition comprising: (a) 4,4'-methylenebis (2,6-di-tert-butylphenol) for use in lubricants (b) 4,4'-methylenebis (2,6-di-tert-butylphenol) -mono- (di-alkyl orthoborate), (c) 4,4'-methylenebis (2,6-di -tert-butylphenol) -di- (di-alkyl orthoborate), (d) alkylated diphenylamine and (e) organomolybdenum compounds.

In another aspect, a lubricating oil or lubricating oil concentrate composition comprising: (a) a hindered phenolic antioxidant, (b) a boron bound to a hindered phenolic oxygen , Single or multiple orthoborate esters derived from a hindered phenolic antioxidant, or combinations thereof and (c) alkylated diphenylamines and (d) organomolybdenum compounds.

Brief Description of the Invention

1 shows the graphical results of Example A.

Detailed description of the invention

Suitable hindered phenols for use in the compositions of the present invention include phenols incorporating 2,6-di-tert-butylphenol moieties. A suitable hindered phenol marketed by ALBEMARLE CORPORATION ^™ under the trade name ETHANOX ^® 702 is 4,4'-methylenebis (2,6-di-tert-butylphenol), hereinafter referred to as MBDTBP and has the structure of structure I Has:

[Structure I]

Other suitable hindered phenols are 2,4-di-tert-butylphenol, 2,6-di-tert-butylphenol, 6-tert-butyl-ortho-cresol, 2,6-di-isopropylphenol, 2, 4-di-sec-butylphenol, high molecular weight hindered phenolic antioxidants (2,4-di-tert-butylphenol, 2,6-di-tert-butylphenol, 6-tert-butyl-ortho-cresol, 2,6-di-isopropylphenol or 2,4-di-sec-butylphenol), butylated hydroxy toluene (BHT) and the like.

The amount of hindered phenol present in the compositions of the present invention ranges from about 1 to about 50% by weight of the total concentration of hindered phenol, boronated hindered phenol and alkylated diphenylamine. In another aspect of the amount of hindered phenol present in the compositions of the present invention, from about 1 to about 40%, about 1 to about 30% by weight of the total concentration of the hindered phenol, boronated hindered phenol and alkylated diphenylamine, From about 1 to about 25 weight percent, from about 1 to about 20 weight percent and from about 1 to about 15 weight percent.

Mono- and di-boronated hindered phenols suitable for use in the compositions of the present invention are derived from the hindered phenols described above by reaction with tri-alkyl orthoborate. One such method is disclosed in US 4,927,553. In one aspect, suitable mono- and di-boronated hindered phenols have the structure of the following structures II and III:

[Structure II]

[Structure III]

Where R ₁ , R ₂ , R ₃ and R ₄ Is independently selected from the group consisting of linear, branched and cyclic C ₁ to C ₈ alkyl groups. Examples of this group are methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, n-pentyl, 2-methylbutyl, 3-methylbutyl, 2-methyl-2-butyl , 3-methyl-2-butyl, isopentyl, n-hexyl, cyclopentyl, cyclohexyl, 2-ethylbutyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 3-methyl-3-pentyl, 3,3-dimethylbutyl, 3,3-dimethyl-2-butyl, 2,3-dimethyl-2-butyl, 2-methyl-2-hexyl , 2,2-dimethyl-3-pentyl, 2-heptyl, 3-heptyl, 2-methyl-3-hexyl, 3-ethyl-3-pentyl, 2,3-dimethyl-3-pentyl, 2,4-dimethyl 3-pentyl, 5-methyl-2-hexyl, 4,4-dimethyl-2-pentyl, 5-methylhexyl, n-heptyl, n-octyl, iso-octyl, 2-ethylhexyl, 2-propylpentyl, 2-octyl, 3-octyl, 2,4,4-trimethylpentyl, 4-methyl-3-heptyl and 6-methyl-2-heptyl.

Other mono- and di-boronated hindered phenols may be derived from reacting tri-alkyl orthoborate with certain hindered phenols or mixtures of hindered phenols described above.

The combined total amount of mono- and di-boronated hindered phenols present in the compositions of the present invention ranges from about 10 to about 80 weight percent of the total concentration of hindered phenols, boronated hindered phenols and alkylated diphenylamines. The ratio of mono-boronated hindered phenol to di-boronated hindered phenol can vary from about 0.01: 1 to about 1: 0.01. The amount of mono-boronically hindered phenol can be approximately equal to or greater than the di-boronated hindered phenol.

The amount of MBDTBP in conventional lubricating oil concentrate compositions has been limited by about 10% by weight of the total added concentrate by its solubility. However, the present invention provides a method for increasing the concentration of a hindered phenolic antioxidant in a lubricating oil concentrate composition by about 50% by weight by including boronized hindered phenolic antioxidant in the lubricating oil concentrate composition.

Alkylated diphenylamines suitable for use in the compositions of the present invention are prepared from diphenylamines by reaction with olefins. One particularly useful method of preparing alkylated diphenylamines is U.S. Patent Publication No. US-2006-0276677-A1, filed on Jun. 2, 2005, which is hereby incorporated by reference in its entirety to the extent permitted by patent law. US Patent Application Provisional Application No. 60 / 687,182 and US Patent Application Serial No. 60/717322, filed on September 14, 2005, which relates to US 11/442856, filed May 30, 2006). Both mono- and di-alkylated diphenylamines can be used alone or in combination and have the structures shown in the following structures IV and V:

[Structure IV]

[Structure V]

Where R ₁ , R ₂ And R ₃ is linear, branched and cyclic C ₄ to C ₃₂ It is independently selected from the group which consists of an alkyl group. Examples of this group include, but are not limited to, alkyl groups derived from linear alpha-olefins, isomerized alpha-olefins, polymerized alpha-olefins, low molecular weight oligomers of propylene and low molecular weight oligomers of isobutylene. Specific examples include butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, dipropyl, tripropyl, tetrapropyl, pentapropyl, hexapropyl, heptapropyl, octapropyl, Diisobutyl, triisobutyl, tetraisobutyl, pentaisobutyl, hexisobutyl, and heptisobutyl.

The combined total amount of mono- and di-alkylated diphenylamines present in the compositions of the present invention ranges from about 10 to about 80 weight percent of the total concentration of the hindered phenols, boronated hindered phenols and alkylated diphenylamines. The ratio of mono- to di-alkylated diphenylamines can vary from about 0.01: 1 to about 1: 0.01.

Examples of suitable alkylated diphenylamines is no biotinylated diphenylamine (NDPA), octanoic tilhwa diphenylamine, mixed oxide tilhwa / styrenated diphenylamine (e.g. Durad ^® AX55) and mixed butylated / octanoic tilhwa diphenylamine (e.g. Vanlube ^® 961). Additionally, the nitrogen content of the alkylated diphenylamine may be in the range of about 2.0 to about 6.0 weight percent. Lower concentrations of nitrogen weaken the effects of alkylated diphenylamines, while higher concentrations of nitrogen can negatively affect the compatibility of the alkylated diphenylamines in the lubricant or the volatility of the lubricants. The alkylated diphenylamines can also be liquid or low melting solids.

Organomolybdenum compounds suitable for use in the present invention include sulfur-free compounds, phosphorus-free compounds and sulfur containing compounds. The molybdenum content of the organomolybdenum compound may vary from about 1% to about 15% by weight. The concentration of the organomolybdenum compound may range from about 1% to about 40% by weight of the total concentration of the hindered phenol, boronated hindered phenol, alkylated diphenylamine, and organomolybdenum compound.

The amount of organomolybdenum compound used in the composition of the present invention has a weight ratio of molybdenum to boron of about 0.01: 1 to about 10: 1. The molybdenum content of the lubricating oil may range from about 50 to about 1000 ppm and the boron content may range from about 50 to about 500 ppm. The molybdenum content of the lubricating oil may range from about 100 to about 400 ppm and the boron content may range from about 100 to about 400 ppm.

Sulfur- and unmanned organomolybdenum compounds can be prepared by reacting sulfur-free and unmanned molybdenum sources with organic compounds containing amino and / or alcohol groups. Examples of sulfur-free and unmanned molybdenum sources include molybdenum trioxide, ammonium molybdate, sodium molybdate and potassium molybdate. The amino group can be a monoamine, diamine or polyamine. The alcohol group may be a mono-substituted alcohol, diol or bis-alcohol or polyalcohol. As an example, the reaction of fatty oil with diamine produces a product containing both amino and alcohol groups that can react with sulfur-free and unmanned molybdenum sources.

Examples of sulfur-free and unmanned organomolybdenum compounds suitable for use in the present invention include: Compounds prepared by reacting some basic nitrogen compounds with molybdenum sources as defined in US Pat. Nos. 4,259,195 and 4,261,843; Compounds prepared by reacting a hydrocarbyl substituted hydroxy alkylated amine with a molybdenum source as defined in US Pat. No. 4,164,473; Compounds prepared by reacting phenol aldehyde condensation products, mono-alkylated alkylene diamines and molybdenum sources as defined in US Pat. No. 4,266,945; Compounds prepared by reacting fatty oil, diethanolamine with a molybdenum source as defined in US Pat. No. 4,889,647; Compounds prepared by reacting fatty oils or fatty acids with 2- (2-aminoethyl) aminoethanol and molybdenum sources as defined in US Pat. No. 5,137,647; Compounds prepared by reacting a secondary amine with a molybdenum source as defined in US Pat. No. 4,692,256; Compounds prepared by reacting a molybdenum source with a diol, diamino or amino-alcohol compound as defined in US Pat. No. 5,412,130; Compounds prepared by reacting fatty oils, mono-alkylated alkylene diamines and molybdenum sources as defined in European Patent Application EP 1 136 496 A1; And compounds prepared by reacting fatty acids, mono-alkylated alkylene diamines, glycerides and molybdenum sources as defined in European patent application EP 1 136 497 A1.

Commercially available sulfur-free and unattended soluble molybdenum compounds are Sakura-Lube 700, manufactured by Asahi Denka, and Molyvan 856B and Molyvan 855, manufactured by R. T. Vanderbilt Company, Inc.

Molybdenum compounds prepared by reacting fatty oil, diethanolamine and molybdenum sources as defined in US Pat. No. 4,889,647 are sometimes described as having one or both of the following structures where R is a fatty alkyl chain:

.

.

The exact chemical structure of such materials is not fully known and may in fact be a multicomponent mixture of many organomolybdenum compounds.

Sulfur-containing organomolybdenum compounds can be prepared in various ways. One method involves reacting sulfur-free and unmanned molybdenum sources with amino groups and one or more sulfur sources. Sulfur sources include carbon disulfide, hydrogen sulfide, sodium sulfide and elemental sulfur. Alternatively, sulfur-containing molybdenum compounds can be prepared by reacting a sulfur-containing molybdenum source with an amino group or thiuram group and optionally a second sulfur source. Examples of sulfur-free and unmanned molybdenum sources include molybdenum trioxide, ammonium molybdate, sodium molybdate, potassium molybdate and molybdenum halides. The amino group can be a monoamine, diamine or polyamine. As an example, the reaction of molybdenum trioxide with secondary amines and carbon disulfides produces molybdenum dithiocarbamate. Alternatively, reaction of (NH ₄ ) ₂ Mo ₃ S ₁₃ .n (H ₂ O) with tetraalkylthiuram disulfide, where n may vary from 0 to 2, results in trinuclear sulfur containing molybdenum dithiocarbamate .

Examples of sulfur-containing organomolybdenum compounds suitable for use in the present invention include: Compounds prepared by reacting molybdenum trioxide with secondary amines and carbon disulfides as defined in US Pat. Nos. 3,509,051 and 3,356,702 ; Compounds prepared by reacting a sulfur-free molybdenum source with secondary amines, carbon disulfides and additional sulfur sources as defined in US Pat. No. 4,098,705; Compounds prepared by reacting molybdenum halides with secondary amines and carbon disulfides as defined in US Pat. No. 4,178,258; Compounds prepared by reacting a molybdenum source with a basic nitrogen compound and a sulfur source as defined in US Pat. Nos. 4,263,152, 4,265,773, 4,272,387, 4,285,822, 4,369,119 and 4,395,343; Compounds prepared by reacting ammonium tetrathiomolybdate with a basic nitrogen compound as defined in US Pat. No. 4,283,295; Compounds prepared by reacting olefin, sulfur, amine and molybdenum sources as defined in US Pat. No. 4,362,633; Compounds prepared by reacting ammonium tetrathiomolybdate with a basic nitrogen compound and an organic sulfur source as defined in US Pat. No. 4,402,840; Compounds prepared by reacting a phenolic compound, an amine and a molybdenum source with a sulfur source as defined in US Pat. No. 4,466,901; Compounds prepared by reacting triglycerides, basic nitrogen compounds, molybdenum sources, and sulfur sources as defined in US Pat. No. 4,765,918; Compounds prepared by reacting an alkali metal alkylthioxateate salt with molybdenum halide as defined in US Pat. No. 4,966,719; Compounds prepared by reacting tetraalkylthiuram disulfide with molybdenum hexacarbonyl as defined in US Pat. No. 4,978,464; Compounds prepared by reacting alkyl dixanthogen with molybdenum hexacarbonyl as defined in US Pat. No. 4,990,271; Compounds prepared by reacting an alkali metal alkylxanthate salt with dimolybdenum tetraacetate as defined in US Pat. No. 4,995,996; Compounds prepared by reacting (NH ₄ ) 2 Mo ₃ S ₁₃ .2 (H ₂ O) with an alkali metal dialkyldithiocarbamate or tetraalkyl thiuram disulfide as defined in US Pat. No. 6,232,276; Compounds prepared by reacting acids, molybdenum sources and carbon disulfides with esters or diamines as defined in US Pat. No. 6,103,674; And compounds prepared by reacting an alkali metal dialkyldithiocarbamate with 3-chloropropionic acid followed by molybdenum trioxide as defined in US Pat. No. 6,117,826.

Examples of commercially available sulfur soluble molybdenum compounds include Sakura-Lube ^® 100, Sakura-Lube ^® 155, Sakura-Lube ^® 165 and Sakura-Lube ^® 180 from Asahi Denka Kogyo KK, Molyvan ^® A from RT Vanderbilt Company , Molyvan ^® 807 and Molyvan ^® 822 and Naugalube ^® MolyFM from Crompton Corporation.

Molybdenum dithiocarbamate is a suitable organomolybdenum compound and has the structure:

Wherein R is independently selected from hydrogen or an alkyl group containing from 4 to 18 carbon atoms and X is independently selected from oxygen or sulfur.

Lubricant can be any basestock or base oil (specified as Group I, II, III, IV, or V defined by the API base stock classification system) or predominantly aromatic, naphthenic, paraffinic. Lubricants consisting of system, polyalpha-olefins and / or synthetic esters. In addition, lubricants may also contain additional additives to make the system usable in a variety of applications. These additives include dispersants, cleaners, viscosity index enhancers, pour point depressants, antiwear agents, extreme pressure additives, friction modifiers, corrosion inhibitors, rust inhibitors, emulsifiers, water separators, antifoams, colorants, seal swelling agents and additional antioxidants. Include.

The present invention relates to passenger car engine oils, diesel engines for heavy vehicles, medium diesel oils, railway rail oils, marine engine oils, natural gas engine oils, two-cycle engine oils, steam turbine oils, gas turbine oils, combined cycle turbine oils. cycle turbine oil, R & O oil, industrial gear oil, automatic gear oil, compressor oil, manual transmission oil, automatic transmission oil, slideway oil, quench oil, flush oil oils and hydraulic fluids. Preferred applications are in engine oils. The most preferred application is in low phosphorus engine oils which are characterized by a phosphorus content of less than 1000 ppm.

The lubricating oil concentrate may or may not contain diluent oil. If diluent oil is used, the diluent oil is typically present in 1 to 80% by weight of the concentrate.

Typically, the total amount of hindered phenol, boronated hindered phenol, alkylated diphenylamine and organomolybdenum compounds added to the fully formulated oil depends on the end use application. For example, in turbine oil, the total amount of the hindered phenol, boronated hindered phenol, alkylated diphenylamine, organomolybdenum compound added to the oil ranges from about 0.05 to about 1.0 weight percent. In contrast, in engine oils, the total amount of hindered phenols, boronated hindered phenols, alkylated diphenyl amines, and organomolybdenum compounds added to the oil ranges from about 0.2 to about 3.0 weight percent. The total amount of hindered phenols, boronated hindered phenols and alkylated diphenylamines in the ultra-low phosphorus engine oil can reach up to 5.0% by weight.

Examples of lubricating oil concentrates according to the invention are as follows:

(a) 10% by weight of 4,4'-methylenebis (2,6-di-tert-butylphenol);

(b) 4,4'-methylenebis (2,6-di-tert-butylphenol) mono- (di-sec-butyl orthoborate) and 4,4'-methylenebis (2,6-di-tert- Butylphenol) di- (di-sec-butyl orthoborate) 40% by weight;

(c) 10% by weight of dinonyldiphenylamine and monononyldiphenylamine;

(d) 20% molybdenum dithiocarbamate containing 4.5% molybdenum; And

(e) 20% by weight paraffinic diluent oil.

Examples of low phosphorus engine oils according to the invention are as follows:

(a) 0.5% by weight of 4,4'-methylenebis (2,6-di-tert-butylphenol);

(b) 4,4'-methylenebis (2,6-di-tert-butylphenol) mono- (di-sec-butyl orthoborate) and 4,4'-methylenebis (2,6-di-tert- Butylphenol) di- (di-sec-butyl orthoborate) 1.0% by weight;

(c) 0.75 wt% dinonyldiphenylamine and monononyldiphenylamine;

(d) 0.2 wt% molybdenum dithiocarbamate containing 4.5 wt% molybdenum;

(e) 4.8 wt% dispersant concentrate;

(f) 1.8% by weight of overbased calcium detergent concentrate;

(g) 0.5 wt% neutral calcium detergent concentrate;

(h) 0.6 wt% zinc dialkyldithiophosphate;

(i) Pour point depressant at 0.1% by weight;

(j) 8.0 weight percent viscosity index improver concentrate;

(k) 0.5 weight percent organic friction modifier; And

(l) 81.25 wt.% paraffinic lubricant.

Example  A: Elevated  Temperature of oil Thickening  And oxidation

The following materials were combined to prepare a preblend of passenger car engine oil in accordance with the present invention:

(a) 5.000 wt% ashless dispersant;

(b) 1.875 weight percent calcium containing overbased detergent;

(c) 0.521 weight percent calcium containing neutral detergent;

(d) 0.625 wt% secondary zinc dialkyldithiophosphate; And

(e) 91.979% by weight 150N group II base oil.

To the preblend of the engine oil was added the components shown in Table 1.

Table 1. Example  Components of A.1 to A.6

Oxidation stability of the finished engine oil was evaluated in the bulk oil oxidation test. Each oil (300 mL) was treated with an iron naphthenate oxidation catalyst to deliver 110 ppm of iron to the finished oil. The oil was heated in a block heater at 150 ° C. during which 10 liters / hour of dry oxygen were bubbled through the oil. Samples of oxidized oil were removed at 24, 48, 72, 96, 120, 144, 168 and 192 hours. The kinematic viscosity of each sample was measured at 40 ° C. The percent increase in viscosity of oxidized oil relative to fresh oil was calculated. The results of the percent increase in viscosity are shown in Table 2.

Table 2. Percentage increase in viscosity of finished oils A.1 to A.6 in bulk oxidized oil tests

The higher percent increase in viscosity is a measure of increased oxidation and degradation of the lubricant. The results clearly show that the inventive antioxidant combinations of Examples A.3 to A.6 provide good oxidation protection compared to other Examples (A.1 to A.2). 4,4'-methylenebis (2,6-di-tert-butylphenol), boronated 4,4'-methylenebis (2,6-di-tert-butylphenol), nonylated diphenylamine and organo Antioxidant systems that do not contain a combination of molybdenum compounds exhibit poor oxidation control, while systems containing BMBDTBP, NDPA, and MoDTC show good oxidation control. These results are shown graphically in FIG. 1.

Example  B-Pressurized Differential Scanning Calorimetry ( PDSC )

Oxidation stability of the finished engine oil prepared in Example A was evaluated using the ASTM standard test method D6186 after pressure differential scanning calorimetry, using the following operating conditions: isothermal = 18O < 0 > C, 100 mL / min. Oxygen gas with a flow rate of @ 500 psig, approximately 3 mg sample size, open aluminum pan. Each oil was treated with an iron naphthenate oxidation catalyst to deliver 55 ppm of iron to the finished oil. Oxidation induction time (OIT) was measured according to the ASTM method. Each oil was tested in two replicates and the results averaged. OIT results are shown in Table 3.

Table 3. PDSC Induction time (min) for finished oils A.1 to A.6 tested using

Longer induction times are a measure of the increased oxidative stability of the lubricant. The results clearly show that the antioxidant combinations of the invention of Examples A.4 to A.6 provide excellent oxidation protection compared to Examples (A.1 to A.2) which are not the invention. Of 4,4'-methylenebis (2,6-di-tert-butylphenol), boronated 4,4'-methylenebis (2,6-di-tert-butylphenol), nonylated diphenylamine and molybdenum Antioxidant systems that do not contain a combination show poor oxidation control, while systems containing BMBDTBP, NDPA and MoDTC show good oxidation control. In addition, oil A.3 of the present invention, compared to non-inventive oil A.2, exhibited the same performance level in PDSC even with significantly less antioxidants, i.e., less than 25% (statistically 112.12 and 110.77 minutes). .

Although the compositions and methods of the invention are described as preferred embodiments, it will be apparent to those skilled in the art that the compositions, methods and / or processes and steps or order of method steps described herein may be altered without departing from the spirit and scope of the invention. Do. More specifically, it is clear that certain agents that are both chemically and physiologically related can be substituted for the agents described herein as long as the same or similar results can be obtained. All such similar substitutions and modifications apparent to those skilled in the art are considered to be within the scope and concept of the invention.

Claims (52)

A lubricating oil composition comprising at least one hindered phenolic antioxidant, at least one boronated hindered phenolic antioxidant, at least one alkylated diphenylamine and at least one organomolybdenum compound. The lubricating oil composition of claim 1, wherein the at least one boronically impaired phenolic antioxidant is derived from at least one impaired phenolic antioxidant. 3. The lubricating oil composition of claim 2, wherein the at least one boronically impaired phenolic antioxidant comprises mono- and di-boronated impaired phenolic antioxidants. 4. The lubricating oil composition of claim 3, wherein the hindered phenolic antioxidant is 4,4'-methylenebis (2,6-di-tert-butylphenol). 5. The mono-boronically impaired phenolic antioxidant of claim 4 has the structure:

, Di-boronated hindered phenolic antioxidants have a lubricating oil composition having the structure:

[In the meal, R ₁ , R ₂ , R ₃ and R ₄ are independently selected from the group consisting of linear C ₁ to C ₈ alkyl groups, branched C ₁ to C ₈ alkyl groups and cyclic C ₃ to C ₈ alkyl groups. 6. The lubricating oil composition of claim 5, wherein the at least one alkylated diphenylamine comprises mono- and di-alkylated diphenylamines. 7. The monoalkylated diphenylamine of claim 6, wherein the monoalkylated diphenylamine has the structure:

, Lubricating oil compositions in which the di-alkylated diphenylamines have the structure:

[In the meal, R ₁ , R ₂ And R ₃ is linear, branched and cyclic C ₄ to C ₃₂ Independently selected from the group consisting of alkyl groups. 8. A group according to claim 7, wherein the mono- and di-alkylated diphenylamines consist of nonylated diphenylamine, octylated diphenylamine, mixed octylated / styrenated diphenylamine and mixed butylated / octylated diphenylamine. Lubricant composition selected from. 4. The lubricating oil composition of claim 3, wherein the organomolybdenum compound is selected from the group consisting of a sulfur-free organo molybdenum compound, a phosphorus-free organomolybdenum compound, and a sulfur-containing organomolybdenum compound. 10. The lubricating oil composition of claim 9, wherein the organomolybdenum compound is molybdenum dithiocarbamate having the structure

[In the meal, R is independently selected from hydrogen or an alkyl group containing from 4 to 18 carbon atoms, and X is independently selected from oxygen or sulfur. The lubricating oil composition of claim 10, wherein the concentration of the organomolybdenum compound is in the range of about 1% to about 40% by weight of the total concentration of the hindered phenol, boronated hindered phenol, alkylated diphenylamine, and organomolybdenum compound. . The lubricating oil composition of claim 11, wherein the weight ratio of molybdenum to boron ranges from about 0.01: 1 to about 10: 1. 13. The lubricating oil composition of claim 12, wherein the molybdenum content ranges from about 50 ppm to about 1000 ppm and the boron content ranges from about 50 ppm to about 500 ppm. The lubricating oil composition of claim 13, wherein the molybdenum content is in the range of about 100 ppm to about 400 ppm and the boron content is in the range of about 100 ppm to about 400 ppm. 5. The total concentration of 4,4'-methylenebis (2,6-di-tert-butylphenol) according to claim 4, wherein the concentration of the hindered phenol, the boronated hindered phenol, the alkylated diphenylamine and the organomolybdenum compound is determined. About 1 to about 50% by weight of the lubricant composition. 16. The method of claim 15 wherein the concentration of mono- and di-boronated hindered phenols is from about 10 to about 80 weight percent of the total concentration of hindered phenols, boronated hindered phenols, alkylated diphenylamines and organomolybdenum compounds. Lubricant composition. The lubricating oil composition of claim 16, wherein the ratio of mono-boronically impaired phenol to di-boronated impaired phenol is from about 1: 1 to about 1: 0.01. 18. The lubricating oil composition of claim 17, wherein the concentration of alkylated diphenylamine is from about 10% to about 80% by weight of the total concentration of the hindered phenol, the boronated hindered phenol, the alkylated diphenylamine, and the organomolybdenum compound. A lubricating oil addition concentrate composition comprising at least one hindered phenolic antioxidant, at least one boronated hindered phenolic antioxidant, at least one alkylated diphenylamine and at least one organomolybdenum compound. 20. A lubricating oil-added concentrated composition according to claim 19, wherein the at least one boronically impaired phenolic antioxidant is derived from at least one impaired phenolic antioxidant. 21. The lubricating oil-concentrated composition of claim 20, wherein the at least one boronically impaired phenolic antioxidant comprises mono- and di-boronated impaired phenolic antioxidants. 22. The lubricating oil-added concentrated composition according to claim 21, wherein the hindered phenolic antioxidant is 4,4'-methylenebis (2,6-di-tert-butylphenol). 23. The mono-boronically impaired phenolic antioxidant of claim 22 has the structure:

, Lubricant-added concentrated composition wherein the di-boronated hindered phenolic antioxidant has the structure:

[In the meal, R ₁ , R ₂ , R ₃ and R ₄ are independently selected from the group consisting of linear C ₁ to C ₈ alkyl groups, branched C ₁ to C ₈ alkyl groups and cyclic C ₃ to C ₈ alkyl groups. 24. The lubricating oil addition concentrate composition of claim 23, wherein the at least one alkylated diphenylamine comprises mono- and di-alkylated diphenylamines. The method of claim 24, wherein the mono-alkylated diphenylamine has the structure

, Lubricant-added concentrated composition wherein the di-alkylated diphenylamine has the following structure:

[In the meal, R ₁ , R ₂ And R ₃ is linear, branched and cyclic C ₄ to C ₃₂ Independently selected from the group consisting of alkyl groups. 26. The group of claim 25, wherein the mono- and di-alkylated diphenylamines consist of nonylated diphenylamines, octylated diphenylamines, mixed octylated / styrenated diphenylamines, and mixed butylated / octylated diphenylamines. Lubricant-added concentrated composition selected from. 22. The lubricating oil composition of claim 21, wherein the organomolybdenum compound is selected from the group consisting of sulfur-free organomolybdenum compounds, unmanned organomolybdenum compounds, and sulfur-containing organomolybdenum compounds. 28. The lubricating oil composition of claim 27, wherein the organomolybdenum compound is molybdenum dithiocarbamate having the structure

[In the meal, R is independently selected from hydrogen or an alkyl group containing from 4 to 18 carbon atoms, and X is independently selected from oxygen or sulfur. The lubricating oil composition of claim 28, wherein the concentration of the organomolybdenum compound is in the range of about 1% to about 40% by weight of the total concentration of the hindered phenol, boronated hindered phenol, alkylated diphenylamine, and organomolybdenum compound. . The total concentration of the hindered phenols, boronated hindered phenols, alkylated diphenylamines, and organomolybdenum compounds of claim 22, From about 1 to about 50% by weight of a lubricating oil-added concentrated composition. 31. The method of claim 30 wherein the concentration of mono- and di-boroning hindered phenols is from about 10 to about 80 weight percent of the total concentration of hindered phenols, boronated hindered phenols, alkylated diphenylamines and organomolybdenum compounds. Lubricant-added concentrated composition. 32. The lubricating oil concentrate composition according to claim 31, wherein the ratio of mono-boronically hindered phenol to di-boronated hindered phenol is from about 1: 1 to about 1: 0.01. 33. The lubricating oil addition concentrate composition of claim 32, wherein the concentration of alkylated diphenylamine is from about 10 to about 80 weight percent of the total concentration of the hindered phenol, the boronated hindered phenol, the alkylated diphenylamine and the organomolybdenum compound. 34. The lubricating oil addition concentrate composition of claim 33, further comprising diluent oil. 35. The lubricating oil addition concentrate composition of claim 34, wherein the concentration of diluent oil is from about 1 to about 80 weight percent. An engine oil composition comprising at least one hindered phenolic antioxidant, at least one boronated hindered phenolic antioxidant, at least one alkylated diphenylamine and at least one organomolybdenum compound. 37. The engine oil composition of claim 36, wherein the hindered phenolic antioxidant is 4,4'-methylenebis (2,6-di-tert-butylphenol). 38. The engine oil composition of claim 37, wherein the at least one boronically impaired phenolic antioxidant comprises: Mono-boronated hindered phenolic antioxidants having the structure:

And Di-boronated hindered phenolic antioxidants having the structure:

[In the meal, R ₁ , R ₂ , R ₃ and R ₄ are independently selected from the group consisting of linear C ₁ to C ₈ alkyl groups, branched C ₁ to C ₈ alkyl groups and cyclic C ₃ to C ₈ alkyl groups. The engine oil composition of claim 38, wherein the at least one alkylated diphenylamine comprises: Mono-alkylated diphenylamines having the structure:

And Di-alkylated diphenylamines having the structure:

[In the meal, R ₁ , R ₂ And R ₃ is linear, branched and cyclic C ₄ to C ₃₂ Independently selected from the group consisting of alkyl groups. 40. The group of claim 39, wherein the mono- and di-alkylated diphenylamines consist of nonylated diphenylamine, octylated diphenylamine, mixed octylated / styrenated diphenylamines and mixed butylated / octylated diphenylamines. Engine oil composition selected from. 41. The engine oil composition of claim 40, wherein the organomolybdenum compound is molybdenum dithiocarbamate having the structure

[In the meal, R is independently selected from hydrogen or an alkyl group containing from 4 to 18 carbon atoms, and X is independently selected from oxygen or sulfur. 42. The total concentration of 4,4'-methylenebis (2,6-di-tert-butylphenol) of claim 41, wherein the concentration of the hindered phenol, boronated hindered phenol, alkylated diphenylamine and organomolybdenum compounds From about 1 to about 50 weight percent of the mono- and di-boronated hindered phenols, and the concentration of the hindered phenols, boronated hindered phenols, alkylated diphenylamines and organomolybdenum compounds from about 10 to about 80 wt%, the ratio of mono-boronated hindered phenol to di-boroned hindered phenol is from about 1: 1 to about 1: 0.01, and the concentration of alkylated diphenylamine is hindered phenol, boronated hindered phenol, From about 10% to about 80% by weight of the total concentration of alkylated diphenylamine and organomolybdenum compounds, wherein the concentration of organomolybdenum compound is a total of hindered phenol, boronated hindered phenol, alkylated diphenylamine and organomolybdenum compounds About 1 to about 40 weight percent of the engine A composition. 43. The engine oil composition of claim 42, wherein the engine oil is used to lubricate an engine selected from the group consisting of gasoline engines, heavy vehicle diesel engines, natural gas engines, marine engines, and railway rail engines. An engine oil added concentrated composition comprising at least one hindered phenolic antioxidant, at least one boronated hindered phenolic antioxidant, at least one alkylated diphenylamine and at least one organomolybdenum compound. 45. The engine oil addition concentrate composition according to claim 44, wherein the hindered phenolic antioxidant is 4,4'-methylenebis (2,6-di-tert-butylphenol). 46. The engine oil added concentrate composition of claim 45, wherein the at least one boronically impaired phenolic antioxidant comprises: Mono-boronated hindered phenolic antioxidants having the structure:

And Di-boronated hindered phenolic antioxidants having the structure:

[In the meal, R ₁ , R ₂ , R ₃ and R ₄ are independently selected from the group consisting of linear C ₁ to C ₈ alkyl groups, branched C ₁ to C ₈ alkyl groups and cyclic C ₃ to C ₈ alkyl groups. 47. An engine oil added concentrate composition according to claim 46, wherein the at least one alkylated diphenylamine comprises: Mono-alkylated diphenylamines having the structure:

And Di-alkylated diphenylamines having the structure:

[In the meal, R ₁ , R ₂ And R ₃ is linear, branched and cyclic C ₄ to C ₃₂ Independently selected from the group consisting of alkyl groups. 48. The group of claim 47, wherein the mono- and di-alkylated diphenylamines consist of nonylated diphenylamine, octylated diphenylamine, mixed octylated / styrenated diphenylamines and mixed butylated / octylated diphenylamines. Engine oil addition concentrated composition selected from. 49. The engine oil addition concentrate composition according to claim 48, wherein the organomolybdenum compound is molybdenum dithiocarbamate having the structure

[In the meal, R is independently selected from hydrogen or an alkyl group containing from 4 to 18 carbon atoms, and X is independently selected from oxygen or sulfur. 50. The total concentration of 4,4'-methylenebis (2,6-di-tert-butylphenol) according to claim 49, wherein the concentration of the 4,4'-methylenebis (2,6-di-tert-butylphenol) is impaired. From about 1 to about 50 weight percent of the mono- and di-boronated hindered phenols, and the concentration of the hindered phenols, boronated hindered phenols, alkylated diphenylamines and organomolybdenum compounds from about 10 to about 80 wt%, the ratio of mono-boronated hindered phenol to di-boroned hindered phenol is from about 1: 1 to about 1: 0.01, and the concentration of alkylated diphenylamine is hindered phenol, boronated hindered phenol, From about 10% to about 80% by weight of the total concentration of alkylated diphenylamine and organomolybdenum compounds, wherein the concentration of organomolybdenum compound is a total of hindered phenol, boronated hindered phenol, alkylated diphenylamine and organomolybdenum compounds About 1 to about 40 weight percent of the engine Be added concentrated composition. 51. The engine oil addition concentrate composition according to claim 50, wherein the engine oil is used for lubricating an engine selected from the group consisting of gasoline engines, heavy vehicle diesel engines, natural gas engines, marine engines, and railway rail engines. A method of increasing the concentration of one or more hindered phenolic antioxidants in a lubricating oil concentrate composition, the method comprising adding one or more boronically hindered phenolic antioxidants to a lubricating oil concentrate.

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