JPH11302678A - Antioxidative lubricating oil additive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new antioxidative lubricating oil additive which can be added to all the kinds of lubricating oil by using a specific polyamine compd. as the additive. SOLUTION: The additive is a polyamine compd. of the formula (wherein R<1> and R<2> are each an alkylene; R<3> is H or a hydrocarbon group; and m and n are each 1 or higher). Pref., in the formula, m is 1; R<1> and R<2> are both ethylene; and R<3> H, an 1-18C alkyl, alkenyl, or aryl, Pref., a lubricating oil compsn. is prepd. by compounding a lube base oil with the additive in an amt. of 0.01-20 wt.% of the base oil. A mineral oil, a synthetic oil, or a mixture thereof can be used as the base oil. If necessary, the additive can be used jointly with other lubricating oil additives, such as an oiliness improver, a friction modifier, an extreme pressure agent, an antioxidant, a detergent, a dispersant, a viscosity index improver, and a rust preventive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an antioxidant lubricating oil additive and a lubricating oil composition containing the same.

[0002]

2. Description of the Related Art Lubricating oils deteriorate over time because they are subjected to physical shearing during use or exposed to an oxidizing atmosphere at high temperature and high pressure. The same applies to various additives that are added to lubricating oils, when they undergo oxidative deterioration before exhibiting their original performance and decompose to fail to exhibit their performance, or adversely affect the lubricating oil. There is also.

[0003] In recent years, lubricating apparatuses are required to have high speed, high output, miniaturization, maintenance-free operation, and the like. Along with this, various problems have also occurred in lubricating oil. For example, a reduction in the size of a lubricating device has led to a decrease in the amount of lubricating oil. Also, since three-way catalysts have become widespread in order to suppress the generation of nitrogen oxides (NO _x ) in exhaust gas, the amount of NO _x gas leaking into the crankcase increases, which accelerates the deterioration of lubricating oil. ing. Further, from the requirement of maintenance-free, lubricating oils are required to have long life, that is, long drain properties. As described above, the demand for lubricating oils to have high stability under severe conditions is increasing year by year.

On the other hand, in recent years, attempts have been made to improve the temperature-viscosity characteristics of the lubricating base oil itself in order to improve the problem of seizure at high temperatures and the problem of energy loss at low temperatures. That is, the use of a refined base oil obtained by highly refining a mineral oil obtained from crude oil as a base oil or a synthetic base oil synthesized by chemical means is increasing. For this reason, components having antioxidant performance, such as sulfur compounds and nitrogen compounds, which are impurities originally contained in mineral oil, have been eliminated, and the problem that the thermal stability of the lubricating base oil alone is reduced. Has occurred.

[0005]

SUMMARY OF THE INVENTION Under such circumstances,
In recent years, the importance of antioxidants added to lubricating oils has increased. Examples of the antioxidant lubricating oil additive generally include a hindered phenol-based antioxidant, a sulfur-containing antioxidant, and a metal antioxidant such as zinc dialkyldithiophosphate.

As other antioxidant lubricating oil additives, there are amine antioxidants. Examples of the amine-based antioxidant include diphenylamines, phenyl-α-naphthylamines, and phenylenediamines. Examples of blending these in lubricating oils include, for example,
No. 95297 discloses that mineral oil or synthetic oil is used as a base oil,
-P-alkylphenyl-α-naphthylamine or p,
A lubricating oil composition containing p'-dialkyldiphenylamine is disclosed. JP-A-3-215596 discloses a lubricant compound having a high degree of stability against oxidative decomposition of a lubricating oil by incorporating diphenylamine or phenothiazine into a lubricating base oil. JP-A-9-53087 discloses a lubricant antioxidant comprising a styrenated diphenylamine-based compound.

[0007] However, the types of base oils of current lubricating oils are diverse. Not only mineral base oils separated and refined from crude oil, but also chemically synthesized synthetic oils such as polybutene, hindered esters and polyalkylene glycol derivatives are used, and when used as a mixed base oil of these and mineral oil There is also. For this reason, depending on the base oil used, it is assumed that the amine-based antioxidant as disclosed in the above prior art has insufficient antioxidant performance. Accordingly, an object of the present invention is to provide a novel amine-based antioxidant lubricating oil additive.

[0008]

That is, the present invention provides the following general formula (1):

Embedded image (Wherein, R ¹ and R ² represent an alkylene group, R ³ represents a hydrogen atom or a hydrocarbon group, m represents a number of 1 or more, and n represents a number of 1 or more). An antioxidant lubricating oil additive comprising a compound and a lubricating oil composition obtained by blending the same with a lubricating base oil.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The antioxidant lubricating oil additive of the present invention comprises a polyamine compound represented by the above general formula (1). In the general formula (1), R ¹ and R ² are an alkylene group. Examples of the alkylene group include an ethylene group, a propylene group, and a butylene group. When m is 1, an ethylene group or a propylene group is preferable, and when m is 2 or more, an ethylene group is preferable.

R ³ represents a hydrogen atom or a hydrocarbon group.
Examples of the hydrocarbon group include an alkyl group, an alkenyl group,
Examples include an aryl group, a cycloalkyl group, and a cycloalkenyl group. Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, isobutyl,
Secondary butyl, tertiary butyl, pentyl, isopentyl, secondary pentyl, neopentyl, tertiary pentyl, hexyl, secondary hexyl, heptyl, secondary heptyl, octyl, 2-ethylhexyl, secondary octyl, nonyl, secondary nonyl, Decyl, secondary decyl, undecyl,
Secondary undecyl, dodecyl, secondary dodecyl, tridecyl, isotridecyl, secondary tridecyl, tetradecyl,
Secondary tetradecyl, hexadecyl, secondary hexadecyl,
Stearyl, icosyl, docosyl, tetracosyl, triacontyl, 2-butyloctyl, 2-butyldecyl,
2-hexyloctyl, 2-hexyldecyl, 2-octyldecyl, 2-hexyldecyl, 2-octyldodecyl, 2-decyltetradecyl, 2-dodecylhexadecyl, 2-hexadecyloctadecyl, 2-tetradecyloctadecyl, monomethyl Branched-isostearyl and the like.

Examples of the alkenyl group include vinyl, allyl, propenyl, butenyl, isobutenyl, pentenyl, isopentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tetradecenyl, oleyl and the like.

Examples of the aryl group include phenyl, toluyl, xylyl, cumenyl, mesityl, benzyl, phenethyl, styryl, cinnamyl, benzhydryl, trityl, ethylphenyl, propylphenyl, butylphenyl, pentylphenyl, hexylphenyl, heptylphenyl, octyl. Phenyl, nonylphenyl, decylphenyl, undecylphenyl, dodecylphenyl,
Examples include phenylphenyl, benzylphenyl, styrenated phenyl, p-cumylphenyl, α-naphthyl and β-naphthyl groups.

Examples of the cycloalkyl group and the cycloalkenyl group include, for example, cyclopentyl, cyclohexyl, cycloheptyl, methylcyclopentyl, methylcyclohexyl, methylcycloheptyl, cyclopentenyl, cyclohexenyl, cycloheptenyl, methylcyclopentenyl, methylcyclohexenyl, methylcyclohepenyl And a thenyl group.

Among these, an alkyl group, alkenyl group or aryl group having 1 to 18 carbon atoms is preferred. Note that m
× n R ^{3 s} are each independent and may be the same or different.

The antioxidant lubricating oil additive of the present invention is used by being blended with a lubricating base oil. The compounding amount is not particularly limited, but if the amount is too small, the antioxidant effect is not sufficiently exhibited, and if the amount is too large, sludge is caused. Therefore, the preferable compounding amount is 0.01 to 20% by weight based on the lubricating oil base oil, Preferably it is 0.05 to 15% by weight.

The lubricating base oil that can be used may be any of mineral oil, synthetic oil and mixtures thereof.
The kinematic viscosity of the lubricating base oil is not particularly limited, but is preferably 1 to 50 cSt at 100 ° C and 10 to 1,000 at 40 ° C.
about cSt, viscosity index (VI) is preferably 70 or more,
More preferably, it is 100 or more.

Mineral oil is separated from natural crude oil, and is produced by appropriately distilling, refining, and the like.
Main component of mineral oil is hydrocarbon (mostly paraffins)
And further contains a naphthene component, an aromatic component, and the like. Lubricating base oils that have been subjected to hydrorefining, solvent dewaxing, solvent extraction, solvent dewaxing, hydrogen dewaxing, catalytic dewaxing, hydrocracking, alkali distillation, sulfuric acid washing, clay treatment, etc. are also preferred. Can be used. These purification means are appropriately combined, and it is effective to repeat the same treatment in a plurality of stages. For example, (A) a method in which a distillate is subjected to a solvent extraction treatment or a solvent extraction treatment followed by a hydrogenation treatment and then a sulfuric acid washing, (B) a method in which a distillate oil is subjected to a hydrogenation treatment and then a dewaxing treatment, (C) a method of subjecting a distillate oil to a solvent treatment followed by hydrotreating, (D) a method of subjecting a distillate oil to a solvent extraction treatment and then treating a clay, and (E).
A method in which the distillate is subjected to two-stage or three-stage hydrotreatment, or alkali distillation or sulfuric acid washing treatment thereafter,
(F) A method of subjecting a distillate to hydrogenation or a method of alkali distillation or sulfuric acid washing after hydrogenation, or a method of mixing these treated oils is effective.

By performing these treatments, it is possible to remove aromatic components, sulfur components, nitrogen components, and the like. According to the present technology, these impurities can be removed to a trace amount or less, but the aromatic component has an effect of making the lubricating oil additive easy to dissolve. There is also. For example, the sulfur and nitrogen content in currently used highly refined mineral oil is 0.01% by weight or less, and in some cases 0.005% by weight or less. On the other hand, the aromatic content is 1
% By weight, in some cases 0.05% by weight or less, and 3% by weight remaining.

The synthetic oil is a chemically synthesized lubricating base oil such as poly-α-olefin, polyisobutylene (polybutene), diester, polyol ester, phosphate ester, silicate ester, and the like. Polyalkylene glycol, polyphenyl ether, silicone,
Examples include fluorinated compounds and alkylbenzenes. Among them, poly-α-olefin, polyisobutylene (polybutene), diester, polyol ester,
Polyalkylene glycol and the like can be used for general purposes, and can be preferably used for internal combustion engine oil, processing oil and the like.

Examples of the poly-α-olefin include 1
-Hexene, 1-octene, 1-nonene, 1-decene,
Examples thereof include those obtained by polymerizing or oligomerizing 1-dodecene, 1-tetradecene, and the like, and those obtained by hydrogenating them. Examples of the diester include glutaric acid,
Examples include dibasic acids such as adipic acid, azelaic acid, sebacic acid and dodecane diacid, and diesters of alcohols such as 2-ethylhexanol, octanol, decanol, dodecanol and tridecanol. Examples of the polyol ester include neopentyl glycol, trimethylolethane, trimethylolpropane, glycerin, pentaerythritol, sorbitol, dipentaerythritol, tripentaerythritol, or a polyol such as an alkylene oxide adduct thereof, butyric acid, isobutyric acid, Esters with fatty acids such as valeric acid, isovaleric acid, pivalic acid, capric acid, caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, and oleic acid. Examples of the polyalkylene glycol include polyethylene glycol, polypropylene glycol, polyethylene glycol monomethyl ether, mono- or dimethyl ether of a block or random copolymer of ethylene oxide / propylene oxide, and the like.

Since these synthetic oils are each chemically synthesized, they are single substances or mixtures of homologues. Therefore, for example, synthetic oils such as poly-α-olefin, polyisobutylene (polybutene), diester, polyol ester, and polyalkylene glycol are used as impurities contained in mineral oil such as benzene, polycyclic condensed aromatic components, and thiophene. Of sulfur, nitrogen such as indole and carbazole are not included.

The antioxidant lubricating oil additive of the present invention comprises:
If necessary, it can be used in combination with other lubricating oil additives. Representative lubricating oil additives include oil agents, friction modifiers, extreme pressure agents, antioxidants, detergents, dispersants, viscosity index improvers, defoamers, rust inhibitors, pour point depressants, etc. No.

Examples of the oily agent include fatty acids such as capric acid, caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, behenic acid, linoleic acid and linolenic acid, lauryl alcohol, myristyl alcohol , Palmityl alcohol, stearyl alcohol, alcohols such as oleyl alcohol, laurylamine, myristylamine, palmitylamine, stearylamine, amines such as oleylamine,
Examples include amides such as laurylamide, myristylamide, palmitylamide, stearylamine, and oleylamine.

Examples of the friction modifier include capric acid (mono, di, tri) glyceride and caproic acid (mono,
Di, tri) glyceride, caprylic acid (mono, di, tri)
Glyceride, lauric acid (mono, di, tri) glyceride, myristic acid (mono, di, tri) glyceride, palmitic acid (mono, di, tri) glyceride, stearic acid (mono, di, tri) glyceride, oleic acid (mono) ,
Esters such as di- and tri-glycerides; metal salts such as oxymolybdenum dialkyl dithiocarbamate and oxymolybdenum dialkyl dithiophosphate; polyol ethers and polyethers.

Examples of extreme pressure agents include sulfurized olefins,
Sulfurized paraffin, Sulfurized polyolefin, Sulfurized lard, Sulfurized fish oil, Sulfurized whale oil, Sulfurized soybean oil, Sulfurized pinene oil, Sulfurized phenol, Sulfurized alkyl phenol, Dialkyl polysulfide, Dibenzyl disulfide, Diphenyl disulfide, Polyphenylene sulfide, Alkyl mercaptan, Alkyl sulfonic acid, Dithiocarbamine Acid ester, 1,3,4-thiadiazole derivative, thiuram disulfide, butyl (thio, dithio) phosphate, hexyl (thio, dithio) phosphate, octyl (thio,
Dithio) phosphate, 2-ethylhexyl (thio, dithio) phosphate, nonyl (thio, dithio) phosphate, decyl (thio, dithio) phosphate, lauryl (thio, dithio) phosphate, myristyl (thio, dithio) phosphate, palmityl (thio, Dithio) phosphate, stearyl (thio, dithio) phosphate,
Oleyl (thio, dithio) phosphate, phenyl (thio, dithio) phosphate, cresyl (thio, dithio)
(Thio, dithio) phosphoric acids such as phosphates and the like.

As the antioxidant, for example, 2,6-di-
tert.-butylphenol, 2,6-di-tert.-butyl-
p-cresol, 2,6-di-tert.-butyl-4-ethylphenol, 2,4-dimethyl-6-tert.-butylphenol, 4,4′-methylenebis (2,6-di-ter
-butylphenol), 4,4'-bis (2,6-di-tert.-butylphenol), 2,2'-methylenebis (4-methyl-6-tert.-butylphenol), 2,
2'-methylenebis (4-ethyl-6-tert.-butylphenol), 4,4'-butylidenebis (3-methyl-
6-tert.-butylphenol), 2,2′-methylenebis (4-methyl-6-cyclohexylphenol),
2,6-bis (2′-hydroxy-3′-tert.-butyl-5′-methylbenzyl) 4-methylphenol, 3-
tert.-butyl-4-hydroxyanisole, 2-tert.-
Phenolic antioxidants such as butyl-4-hydroxyanisole; 1-naphthylamine, phenyl-1-naphthylamine, p-octylphenyl-1-naphthylamine, p-nonylphenyl-1-naphthylamine, p-dodecylphenyl-1-naphthylamine , Phenyl-2-
Naphthylamine-based antioxidants such as naphthylamine;
N'-diisopropyl-p-phenylenediamine, N,
N'-diisobutyl-p-phenylenediamine, N,
N'-diphenyl-p-phenylenediamine, N, N '
-Di-β-naphthyl-p-phenylenediamine, N-phenyl-N′-isopropyl-p-phenylenediamine, N-cyclohexyl-N′-phenyl-p-phenylenediamine, N-1,3-dimethylbutyl-N Phenylenediamine antioxidants such as' -phenyl-p-phenylenediamine, dioctyl-p-phenylenediamine, phenylhexyl-p-phenylenediamine, phenyloctyl-p-phenylenediamine; dipyridylamine, diphenylamine, p, p'- Di-n-butyldiphenylamine, p, p'-di-tert. -Butyldiphenylamine, p, p'-di-tert. -Pentyldiphenylamine, p, p'-dinonyldiphenylamine, p,
p'-didecyldiphenylamine, p, p'-didodecyldiphenylamine, p, p'-distyryldiphenylamine, p, p'-dimethoxydiphenylamine, 4,
And diphenylamine-based antioxidants such as 4'-bis (4-α, α-dimethylbenzoyl) diphenylamine and p-isopropoxydiphenylamine.

Examples of the detergent include calcium sulfonate, calcium phenate, calcium salicylate, magnesium sulfonate, magnesium phenate, magnesium salicylate, barium sulfonate, barium phenate, and barium salicylate. Examples of the dispersant include polyalkenyl succinimide, polyalkenyl succinimide boride, benzylamine and the like. Examples of the viscosity index improver include poly (meth) acrylate, polyisobutylene, polystyrene, ethylene-propylene copolymer, styrene-isobutylene copolymer and the like.

The lubricating oil additive of the present invention can be used by adding to lubricating oils for various uses. For example, industrial lubricating oils,
Examples include turbine oil, machine oil, bearing oil, compressor oil, hydraulic oil, hydraulic oil, internal combustion engine oil, refrigeration oil, gear oil, oil for automatic transmission, transaxle fluid, metalworking oil, various greases, and the like. Among them, it is suitable as an antioxidant for internal combustion engine oils such as vehicle engines, two-cycle engines, aircraft engines, marine engines, and locomotive engines. Examples of the internal combustion engine include a gasoline engine, a diesel engine, a jet engine, a gas turbine engine, an alcohol engine, and the like.

[0029]

EXAMPLES The present invention will be described more specifically with reference to the following examples. In the following examples, parts and percentages are by weight unless otherwise specified. The antioxidant lubricating oil additives of the present invention used in the tests are as follows: (Sample 1)

Embedded image

(Sample 2)

Embedded image

(Example 1) Base oil (commercial product: 120N oil)
To 100 parts, 0.1 part or 0.3 part of Sample 1 or 2 was added, and the differential heat was measured. The instrument used for the measurement was a high-speed differential thermal balance TGD-7000RH manufactured by Vacuum Riko Co., Ltd.
Type.

[0032]

[Table 1] As described above, the product of the present invention has antioxidant performance.

(Example 2) Base oil (commercial product: 120N oil)
To 100 parts, add 0.3 part of sample 1 or 2 and JIS-
The viscosity after deterioration and the total acid value were measured according to K-2415. <Conditions> Temperature: 165.5 ° C Rotation speed: 1,300 rpm Time: 24 hours

[0034]

[Table 2] As described above, the product of the present invention has antioxidant performance.

[0035]

The effect of the present invention is to provide a novel amine-based antioxidant lubricating oil additive and a lubricating oil composition containing the same.

Claims (4)

[Claims] 1. The following general formula (1): (Wherein, R ¹ and R ² represent an alkylene group, R ³ represents a hydrogen atom or a hydrocarbon group, m represents a number of 1 or more, and n represents a number of 1 or more). An antioxidant lubricating oil additive consisting of a compound. 2. In the general formula (1), m is 1.
R ¹ and R ² is an ethylene group, R ³ is a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, an alkenyl group or an aryl group, antioxidant lubricating oil additive of claim 1. 3. A lubricating oil composition containing the antioxidant lubricating oil additive according to claim 1 or 2 in a lubricating base oil. 4. The antioxidant lubricant additive according to claim 1 or 2 is added to the lubricating base oil in an amount of from 0.01 to 0.01%.
A lubricating oil composition containing 20% by weight.