JP5717501B2 - Alkyl monoether alkyl monoester compounds, lubricating base oils, lubricating oils, grease base oils, and greases - Google Patents

Description

  The present invention relates to an alkyl monoether alkyl monoester compound, a lubricating base oil, a lubricating oil, a grease base oil, a grease, and an intermediate for producing an alkyl monoether alkyl monoester compound.

Lubricating oils are used in a wide range of temperature environments from low to high temperatures. Therefore, for example, a fluid bearing or an impregnated bearing used in a motor such as a hard disk drive is required to have a high viscosity index and good low temperature fluidity. In addition, a grease base oil having a high viscosity index and good low-temperature fluidity is also required for grease used in a wide temperature range from low temperature to high temperature.
In order to answer such needs, various base oils have been proposed. For example, a predetermined diester base oil that has both a high viscosity index and low temperature fluidity has been proposed for lubricating oils or greases (see, for example, Patent Documents 1 to 3).

JP 2003-321691 A JP 2010-275471 A JP 2007-039496 A

  However, even if the base oils described in Patent Documents 1 to 3 are used, lubricating oils and greases that sufficiently satisfy both the high viscosity index and the low temperature fluidity at various kinematic viscosities used in actual equipment are provided. It is difficult.

  The present invention relates to a compound having a high viscosity index and excellent low-temperature fluidity compared to a compound having a similar kinematic viscosity, a lubricating base oil, a grease base oil, and a mixture of these compounds. It is an object of the present invention to provide used lubricating oils, greases, and production intermediates of the compounds.

  In order to solve the above problems, the present invention provides the following alkyl monoether alkyl monoester compounds, lubricating base oils, lubricating oils, grease base oils, greases, and production intermediates for alkyl monoether alkyl monoester compounds. To do.

[1] An alkyl monoether alkyl monoester compound of 2,4-diethyl-1,5-pentanediol, which is represented by the following general formula (1):

（前記式において、アルキル基Ｒ、Ｒ’の炭素数は独立に５から１８までであり、前記式の化合物における総炭素数は２４から４０までである。）

(In the above formula, the alkyl groups R and R ′ independently have 5 to 18 carbon atoms, and the total carbon number in the compound of the above formula is 24 to 40.)

[2] A lubricating base oil comprising the alkyl monoether alkyl monoester compound described in [1] above.
[3] A lubricating oil characterized by using the lubricating base oil described in [2] above.
[4] A lubricating oil according to the above [3], wherein the lubricating oil is for oil-impregnated bearings or fluid bearings.
[5] A grease base oil comprising the alkyl monoether alkyl monoester compound described in [1] above.
[6] A grease characterized by using the grease base oil described in [5] above.
[7] Production of alkyl monoether alkyl monoester compound according to [1] above, which is represented by the following general formula (2) Intermediates.

（前記式において、アルキル基Ｒ’の炭素数は５から１８までである。）

(In the above formula, the alkyl group R ′ has 5 to 18 carbon atoms.)

  According to the novel alkyl monoether alkyl monoester compound of the present invention represented by the general formula (1), it has a high viscosity index and excellent low temperature fluidity. Therefore, it is useful as a base oil for lubricating oil and can be suitably used as a lubricating oil for oil-impregnated bearings or fluid bearings. It is also useful as a grease base oil and a grease formed by blending it. Furthermore, in producing the novel alkyl monoether alkyl monoester compound, the novel compound represented by the general formula (2) is useful as an intermediate.

¹ H NMR chart of 5-nonyloxy-2,4-diethyl-1-pentanol (intermediate) in Examples. IR chart of 5-nonyloxy-2,4-diethyl-1-pentanol (intermediate) in the examples. ¹ H NMR chart of dodecanoic acid 5-nonyloxy-2,4-diethyl-1-pentyl ester in Examples. IR chart of dodecanoic acid 5-nonyloxy-2,4-diethyl-1-pentyl ester in Examples.

  The present invention provides an alkyl monoether alkyl monoester compound of 2,4-diethyl-1,5-pentanediol represented by the following general formula (1).

ここで、式（１）において、アルキル基Ｒ、Ｒ’の炭素数は独立に５から１８までである。アルキル基Ｒの炭素数が４以下であると粘度指数が低くなるおそれがあり、万一加水分解を起こしたとき、低級脂肪酸を生成して腐食の原因となるおそれもある。
一方、アルキル基Ｒの炭素数が１９以上であると動粘度が上昇し、低温度領域での流動性が悪くなり、場合によっては固化してしまうおそれがある。それ故、アルキル基Ｒの特に好ましい炭素数は６から１６までである。
また、アルキル基Ｒ’の炭素数が４以下であると粘度指数が低くなるおそれがある。一方、アルキル基Ｒ’の炭素数が１９以上であると粘度指数の低下と高温度領域での蒸発性が高くなるおそれがある。それ故、アルキル基Ｒ’の特に好ましい炭素数は６から１６までである。

Here, in Formula (1), the carbon number of the alkyl groups R and R ′ is independently 5 to 18. If the number of carbon atoms of the alkyl group R is 4 or less, the viscosity index may be lowered. If hydrolysis occurs, a lower fatty acid may be generated and cause corrosion.
On the other hand, if the carbon number of the alkyl group R is 19 or more, the kinematic viscosity increases, the fluidity in the low temperature region is deteriorated, and in some cases, it may be solidified. Therefore, the particularly preferred carbon number of the alkyl group R is 6 to 16.
Further, when the alkyl group R ′ has 4 or less carbon atoms, the viscosity index may be lowered. On the other hand, when the carbon number of the alkyl group R ′ is 19 or more, there is a possibility that the viscosity index is lowered and the evaporability in a high temperature region is increased. Therefore, a particularly preferred carbon number of the alkyl group R ′ is 6 to 16.

  Furthermore, the total number of carbon atoms in the compound of formula (1) is from 24 to 40. If the total number of carbon atoms is 23 or less, the viscosity index is lowered, and the evaporability in a high temperature region may be increased. On the other hand, if the total number of carbon atoms is 41 or more, the kinematic viscosity increases, the fluidity in the low temperature region deteriorates, and in some cases, there is a risk of solidifying. Therefore, it is particularly preferred that the total carbon number is 26 to 36.

  The compound of the above formula (1) can be easily produced, for example, via an intermediate represented by the following general formula (2).

The intermediate (5-alkoxy-2,4-diethyl-1-pentanol) represented by the formula (2) is, for example, a correlation transfer of 2,4-diethyl-1,5-pentanediol and alkyl bromide. It can be produced by heating and stirring in a concentrated alkaline solution in the presence of a catalyst. Preferred reaction conditions and identification methods are as follows.
Temperature: 40-95 ° C (more preferably 60-80 ° C)
Time: 1 to 24 hours (preferably about 8 hours)
Catalyst: Phase transfer catalyst (tetrabutylammonium bromide, tetraisopropylammonium bromide, etc.)
Solvent: Sodium hydroxide aqueous solution with a concentration of 48% by mass or more
(You may replenish solid sodium hydroxide during the reaction.)
Identification: The transition of the reaction can be confirmed by gas chromatography.
(Detailed structure can be identified by mass spectrometry, NMR analysis, IR analysis, etc.)

Then, the monoether (intermediate) is separated by distillation from the mixture of monoether and diether obtained by the above-described production method and used for the production of the compound of formula (1).
Specifically, if 5-alkoxy-2,4-diethyl-1-pentanol and an alkylcarboxylic acid are heated and stirred in the presence of an acid catalyst to carry out an esterification reaction, and the generated water is removed. Good.
Also, the compound of formula (1) can be obtained in high yield by reacting the ether alcohol with alkylcarboxylic acid chloride in the presence of a base at room temperature.
In any reaction, the obtained compound contains impurities, but can be preferably used as a lubricating base oil or a grease base oil by distillation purification.

Two preferred examples of the esterification reaction are given below.
(Reaction of alcohol (formula (2)) with alkyl carboxylic acid)
Temperature: 100 to 190 ° C. (preferably 120 to 180 ° C.)
Time: 1 to 24 hours (more preferably about 8 hours)
Catalyst: Sulfuric acid, Tetrabutyl titanate, Tetraisopropyl titanate, Tetraethyl titanate Solvent: Toluene, xylene, trimethylbenzene, etc. Reactor: Dehydration using a Dean-Stark apparatus .
(Identified by mass analysis, NMR analysis, IR analysis, etc.

(Reaction of alcohol (formula (2)) with alkylcarboxylic acid chloride)
Temperature: 10 to 60 ° C. (more preferably 20 to 40 ° C.)
Time: 1 to 24 hours (more preferably about 4 hours)
Base: N, N-dimethylaniline, triethylamine, etc. Solvent: Tetrahydrofuran, dibutyl ether, dimethyl ether, etc. Identification: The transition of the reaction can be confirmed by gas chromatography.
(It can be identified by mass spectrometry, NMR analysis, IR analysis, etc.)

The compound of the above formula (1) has a high viscosity index and excellent low temperature fluidity. Therefore, it is useful as a base oil for lubricating oil and can be suitably used as a lubricating oil for oil-impregnated bearings or fluid bearings. It is also useful as a grease base oil and a grease formed by blending it.
Moreover, when using the compound of this invention as lubricating oil or base oil of grease, the additive for lubricating oil or grease can be mix | blended as needed. For example, antioxidants, rust preventives, solid lubricants, fillers, oiliness agents, metal deactivators, water resistance agents, extreme pressure agents, antiwear agents, viscosity index improvers, colorants, viscosity modifiers, etc. Is mentioned.
Extreme pressure agents include zinc dialkyldithiophosphates, molybdenum dialkyldithiophosphates, ashless dithiocarbamates, zinc dithiocarbamates, molybdenum dithiocarbamates, sulfur compounds (sulfurized oils, sulfurized olefins, polysulfides, sulfide mineral oils, thiophosphorus Acid, thioterpene, dialkylthiodipyropionate, etc.), phosphate ester, phosphite ester (tricresyl phosphate, triphenyl phosphite, etc.) and the like. Examples of the oily agent include alcohols, carboxylic acids, glycerides, esters and the like. The blending amount of these is preferably about 0.1 to 5% by mass (based on the total amount of lubricating oil or grease).

Examples of the antioxidant include amine-based antioxidants such as alkylated diphenylamine, phenyl-α-naphthylamine, alkylated phenyl-α-naphthylamine, 2,6-di-t-butyl-4-methylphenol, 4,4 Examples thereof include phenol-based antioxidants such as' -methylenebis (2,6-di-t-butylphenol), peroxide-based decomposition agents such as sulfur-based ZnDTP, and the like. Used at a rate of less than%.
Examples of rust preventives include benzotriazole, zinc stearate, succinic acid ester, succinic acid derivative, thiadiazole, benzotriazole, benzotriazole derivative, sodium nitrite, petroleum sulfonate, sorbitan monooleate, fatty acid soap, and amine compound. Can be mentioned.
Examples of the solid lubricant include polyimide, PTFE, graphite, metal oxide, boron nitride, melamine cyanurate (MCA), and molybdenum disulfide.
Further, as a viscosity modifier, a lubricating base oil such as DIOA (diisooctyl adipate) or DIDA (diisodecyl adipate) may be mixed and used in an amount of about 1% by mass to 30% by mass.

EXAMPLES Next, although an Example and a comparative example are given and this invention is demonstrated in more detail, this invention is not restrict | limited to these description content at all.
Table 1 shows specific examples and physical properties of the production intermediate of the formula (2) obtained by the method described in the above embodiment.

Below, the specific manufacturing method of the intermediate body 3 is described as an example.
(Production of 5-nonyloxy-2,4-diethyl-1-pentanol)
Under a nitrogen stream, 320 g (2 mol) of 2,4-diethyl-1,5-pentanediol and 311 g (1.51 g) of n-nonyl bromide were placed in a 2 L reactor equipped with a stirrer, a thermometer, a cooling pipe and a gas introduction pipe. Mol) and 12 g of tetrabutylammonium bromide were added, 532 g of a 52 mass / volume% aqueous sodium hydroxide solution was added, and the mixture was heated and stirred at 70-80 ° C. for 6 hours. After completion of the reaction, the mixture was left standing to cool overnight to precipitate white crystals, and the liquid layer was transferred to a separatory funnel by decantation. The white crystals were washed with 20 mL of hexane, and the hexane washing solution was added to the liquid layer.
The lower alkali layer was separated and removed, and the organic layer was washed with 500 mL of saturated brine and 100 mL of dilute sulfuric acid aqueous solution, washed with distilled water until neutral, and then the obtained organic layer was dried over magnesium sulfate.
After passing this organic layer through a column layer of 50 g of silica gel, mass analysis, NMR analysis and IR analysis of components fractionated by distillation under reduced pressure were carried out, and 5-nonyloxy-2,4-diethyl-1- It was confirmed that it was pentanol (mass analysis result m / z = 286). The amount obtained was 284 g (66% yield). The distillation residue was mainly 1,5-dinonyloxy-2,4-diethyl-1-pentane.
A ¹ H NMR chart of this compound is shown in FIG. 1, and an IR chart is shown in FIG.

  Table 2 shows the physical properties of the monoester compound of the formula (1) obtained by the method described in the above embodiment and the diester compound for comparison.

Below, the specific manufacturing method of the compound 4 is described as an example.
(Production of dodecanoic acid 5-nonyloxy-2,4-diethyl-1-pentyl ester)
In a 1 L three-necked flask equipped with a stirrer, a thermometer, a cooling tube, and a dropping funnel with a gas introduction tube, 260 g (0.91 mol) of 5-nonyloxy-2,4-diethyl-1-pentanol, N, N-dimethyl 112 g (0.92 mol) of aniline and 150 mL of tetrahydrofuran were charged, and 197 g (0.9 mol) of dodecyl chloride was added dropwise at room temperature under a nitrogen stream, followed by stirring. After dropping, the mixture was heated to 45 ° C. and stirred for 4 hours. After the reaction, a small amount of distilled water is added to dissolve the produced white solid, transferred to a separatory funnel, the aqueous layer is separated, 150 mL of tetrahydrofuran is added to the organic layer, and 300 mL of saturated brine and 20 mL of dilute sulfuric acid are added. Each was washed and washed with distilled water until neutral. The obtained organic layer was dried over magnesium sulfate. After removing the solvent with an evaporator, mass analysis, NMR analysis, and IR analysis were performed on components fractionated by distillation under reduced pressure to confirm that the product was a monoester compound (mass analysis result m / z = 468). . The amount obtained was 185 g (43% yield).
The ¹ H NMR chart of this compound is shown in FIG. 3, and the IR chart is shown in FIG.

  From Table 2, when the compound of the present invention (monoester) and the comparative compound (diester) are compared, in the case of the same kinematic viscosity, the compound of the present invention has a higher viscosity index and is excellent in low-temperature fluidity. I understand that. Therefore, it can also be understood that the compound of the present invention is useful as a base oil for lubricating oils and greases.

Claims (6)

An alkyl monoether alkyl monoester compound of 2,4-diethyl-1,5-pentanediol,
An alkyl monoether alkyl monoester compound represented by the following general formula (1):

(In the above formula, the alkyl groups R and R ′ independently have 5 to 18 carbon atoms, and the total carbon number in the compound of the above formula is 24 to 40.) A lubricating base oil comprising the alkyl monoether alkyl monoester compound according to claim 1. The lubricating base oil according to claim 2 is used. The lubricating oil according to claim 3, wherein the lubricating oil is for oil-impregnated bearings or fluid bearings. A grease base oil comprising the alkyl monoether alkyl monoester compound according to claim 1. A grease comprising the grease base oil according to claim 5.

Images