WO2009148110A1

WO2009148110A1 - Lubricating oil composition and use of same

Info

Publication number: WO2009148110A1
Application number: PCT/JP2009/060231
Authority: WO
Inventors: 良輔金重; 洋樹江端; 秀一松村
Original assignee: 三井化学株式会社; 学校法人慶應義塾
Priority date: 2008-06-04
Filing date: 2009-06-04
Publication date: 2009-12-10
Also published as: JP5398708B2; JPWO2009148110A1

Abstract

Provided is a lubricating oil composition having viscosity characteristics (viscosity index improving effect) and friction characteristics similar to or better than those when a PMA-based viscosity modifier is used. Also provided is a lubricating oil composition having superior biodegradability while having the abovementioned characteristics. The lubricating oil composition includes (A) base oil and (B) ricinolic acid (co)polymer of weight average molecular weight measured by GPC (gel permeation chromatography) of 10,000 or above, in proportions by weight of (A)/(B) from 70/30 to 99.5/0.5.

Description

Lubricating oil composition and use thereof

The present invention relates to a lubricating oil composition containing a ricinoleic acid (co) polymer and its use. More specifically, the present invention relates to a lubricating oil composition containing a ricinoleic acid (co) polymer having good viscosity characteristics and friction characteristics and high biodegradability, and uses thereof.

Petroleum products generally have a so-called viscosity temperature dependency in which the viscosity changes greatly when the temperature changes. The lubricating oil also has a temperature dependency of the viscosity, and it is preferable that the temperature dependency of the viscosity is small. For the purpose of reducing the temperature dependence of the viscosity, a polymer soluble in a lubricating base oil is used as a viscosity index improver. As a typical viscosity modifier, a mineral oil solution of an olefin copolymer or a polymer of polymethacrylate (hereinafter referred to as PMA) is known.

On the other hand, in recent years, with the growing awareness of global environmental issues, development of products with reduced environmental impact is desired in each industry. Such a demand is not an exception for lubricating oil compositions, and lubricating oil compositions having various biodegradability have been proposed.

For example, lubricating oil compositions for grease and engine oil containing vegetable oils such as soybean oil and rapeseed oil as base oils and synthetic esters such as polyols have been proposed (for example, see Non-Patent Document 1).

However, since such a lubricating oil composition has a lower viscosity than the conventional lubricating oil composition, the range of use has been limited.

Further, as a result of examination by the present inventors, a lubricating oil composition containing vegetable oil as a base oil has problems in storage characteristics and stability at low temperatures. When such a lubricating oil composition contains a viscosity modifier such as an OCP (olefin copolymer) viscosity modifier, the viscosity modifier is poorly soluble in vegetable oil and difficult to apply.

Furthermore, the solubility of the viscosity modifier in the base oil is improved by selecting a PMA (polymethacrylate) viscosity modifier as the viscosity modifier of the lubricating oil composition based on vegetable oil or synthetic ester. However, since the PMA-based viscosity modifier contains 50% by weight or more of a mineral oil having a low biodegradation rate as a diluent oil, the biodegradation rate of the lubricating oil composition was significantly reduced.

Then, it makes it a subject to provide the lubricating oil composition which has a viscosity characteristic (viscosity index improvement effect) and a friction characteristic equivalent or more compared with the case where a PMA type | system | group viscosity modifier is used. Another object of the present invention is to provide a lubricating oil composition having excellent biodegradability, which does not include a diluent oil such as mineral oil that has the above-described properties and reduces biodegradability.
Another object of the present invention is to provide a viscosity modifier for lubricating oil that has high biodegradability.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have used a specific ricinoleic acid (co) polymer as a viscosity modifier, so that a lubricating oil can be used as compared with the case where a PMA viscosity modifier is used. It has been found that the composition exhibits an equal or higher viscosity characteristic (viscosity index improving effect) and friction characteristic, and is extremely excellent in biodegradability, and the present invention has been completed.

That is, the lubricating oil composition containing the ricinoleic acid (co) polymer according to the present invention (hereinafter sometimes referred to as a lubricating oil composition for convenience) is specified by the following matters.

The lubricating oil composition according to the present invention comprises (A) a base oil and (B) a ricinoleic acid (co) polymer having a weight average molecular weight of 10,000 or more as measured by GPC (gel permeation chromatography). The weight ratio of (A) to (B) (weight of (A) / weight of (B)) is 70/30 to 99.5 / 0.5.

The base oil is preferably vegetable oil and / or synthetic ester.

The synthetic ester is preferably a diester or a polyol ester, more preferably an aliphatic diester or an aliphatic polyol ester.

The weight average molecular weight of the ricinoleic acid (co) polymer (B) is preferably 10,000 to 300,000.

In addition to (A) and (B), the lubricating oil composition comprises an antioxidant, an extreme pressure agent, a rust inhibitor, a metal deactivator, an antiwear additive, an antifoaming agent and a cleaning dispersant. It is preferable to include at least one additive (C) selected from the group consisting of:
The lubricating oil composition preferably has a biodegradation rate of 60% or more as measured by the modified MITI test method OECD301C method.

The lubricating oil composition is preferably gear oil, hydraulic oil, engine oil, grease, or metalworking oil.

Furthermore, the viscosity adjusting agent for lubrication according to the present invention is characterized by comprising a ricinoleic acid (co) polymer having a weight average molecular weight of 10,000 or more as measured by GPC (gel permeation chromatography).

According to the lubricating oil composition of the present invention, compared with a biodegradable lubricating oil composition composed of a viscosity modifier such as a PMA viscosity modifier and a vegetable oil or a synthetic ester, the lubricating oil composition is equivalent or more. In addition to its viscosity characteristics (viscosity index improving effect) and friction characteristics, it can exhibit excellent biodegradability.

Furthermore, when the base oil is a vegetable oil, good low-temperature storage stability can be exhibited together with the above effects.

Moreover, the viscosity adjusting agent for lubrication of the present invention, when added to the lubricating oil composition, imparts excellent biodegradability to the lubricating oil composition, along with viscosity characteristics (viscosity index improving effect) and friction characteristics. Can do.

Hereinafter, the lubricating oil composition containing the ricinoleic acid (co) polymer according to the present invention (hereinafter, sometimes referred to as a lubricating oil composition for convenience) will be described in detail for each component.
[Base oil (A)]
In the present invention, examples of the base oil (A) include vegetable oils, synthetic esters, low molecular weight poly α-olefins, and the like. Of these, vegetable oils and synthetic esters are preferred.

In addition, since the biodegradability of the lubricating oil composition can be further improved, rapeseed oil, soybean oil, castor oil, palm oil, sunflower oil, safflower oil, corn oil, meadow foam oil, rice bran oil, olive oil, Jojoba oil and the like are preferable, and rapeseed oil, soybean oil, castor oil, and palm oil are more preferable. Moreover, you may use 1 type, or 2 or more types of these vegetable oils.

In addition, the biodegradability of the lubricating oil composition is slightly inferior to the case where the base oil is a vegetable oil, but since the lubricating oil composition can be used under a wide range of temperature conditions, the synthetic ester includes a diester, Polyol esters are preferred.

Furthermore, since the lubricating oil composition can be used under a wide range of temperature conditions from a low temperature range (below room temperature) to a high temperature range (50 ° C. to 100 ° C.), as a diester, di-2-ethylhexyl sebacate, Aliphatic diesters such as dioctyl adipate, dioctyl decanedioate, diisodecyl adipate, and dioctyl sebacate are preferred, and the polyol ester is an aliphatic polyol ester such as pentaerythritol tetraoleate, trimethylolpropane tripelagonate, or neopentyl polyol. Preferably, one or more of these synthetic esters may be used.

As the base oil (A), one or more kinds of vegetable oils and one or more kinds of synthetic esters may be mixed and used.

In order to obtain a lubricating oil composition having appropriate lubricity, the base oil (A) should have a kinematic viscosity at 40 ° C. (according to ASTM 445 kinematic viscosity test method) of 10 to 80 mm ² / s. Is more preferable, and 20 to 60 mm ² / s is more preferable.

In addition, in order to obtain a lubricating oil composition having appropriate fluidity in a low temperature range (room temperature or lower), the pour point of the base oil (A) (according to the measurement method of JIS K2269) should be 0 to -50 ° C. Is preferred.
[Ricinolic acid (co) polymer (B)]
The weight average molecular weight measured from GPC (gel permeation chromatography) of the ricinoleic acid (co) polymer (B) according to the present invention is 10,000 or more, preferably 10,000 to 300,000. More preferably, it is 30,000 to 150,000. By using the ricinoleic acid (co) polymer (B) having a weight average molecular weight in such a range, the lubricating oil composition blended with the ricinoleic acid (co) polymer has excellent viscosity increase and viscosity index improvement effects. And excellent biodegradability can be imparted. Moreover, when base oil is vegetable oil, favorable low-temperature storage stability can be provided.

In addition, ricinoleic acid (co) polymer (B) having a weight average molecular weight in such a range is obtained by using ricinoleic acid (12-hydroxy-cis-9-octadecenoic acid) as shown in the following reaction formula (I). It can be synthesized from an ester derivative or from a ricinoleic acid ester derivative and a hydroxycarboxylic acid ester derivative (for example, 12-hydroxystearic acid methyl ester) through an ester polymerization reaction with lipase.

In the above polymerization reaction, when a ricinoleic acid ester derivative alone is polymerized, polyricinoleic acid which is a homopolymer is obtained. On the other hand, when a hydroxycarboxylic acid ester derivative is copolymerized with a ricinoleic acid ester derivative, a ricinoleic acid copolymer is obtained.

Also, since the ester polymerization reaction is good and a high molecular weight polyricinoleic acid is obtained, the ricinoleic acid ester is preferably methyl ricinoleate.

The ricinoleic acid copolymer is composed of a ricinoleic acid ester derivative and a hydroxycarboxylic acid ester derivative as monomer components. Here, the hydroxycarboxylic acid ester derivative is not particularly limited as long as it is a carboxylic acid ester derivative having a hydroxyl group (hydroxyl group), but is preferably hydroxystearic acid.

Further, the charged molar ratio of the ricinoleic acid ester derivative to the 12-hydroxystearic acid ester derivative (ricinoleic acid ester derivative / 12-hydroxystearic acid ester derivative) is preferably 100/0 to 20/80.

Further, as the ricinoleic acid (co) polymer (B) of the present invention, a polymer obtained by subjecting the polyricinoleic acid or ricinoleic acid copolymer to hydrogenation may be used as desired.

(Scheme I)
The lipase is preferably an immobilized lipase derived from Burkholderia cepacia (for example, Lipase PS-C Amano II (trade name), PS-D Amano I (trade name), etc., manufactured by Wako Chemical Co., Ltd.). Since the lipase is not easily deactivated even at high temperatures, the reaction temperature can be increased to 90 ° C. The reaction conditions are preferably a batch method using a reactor equipped with a stirrer under bulk conditions.

The reaction time is usually 4 to 7 days, although it varies depending on conditions such as catalyst concentration and polymerization temperature.

Further, as shown in the above reaction formula (I), the ester polymerization reaction using lipase is a reversible reaction, and it is preferable to sequentially remove the produced alcohol in order to advance the efficient ester polymerization reaction. . Specifically, maintaining the pressure state in the reaction system in a reduced pressure state, or performing a synthesis reaction after placing a hygroscopic agent such as synthetic zeolite (for example, molecular sieve 4A) in the reaction system in a non-contact manner. Is mentioned. By carrying out the ester polymerization reaction under such conditions, the ester polymerization reaction can be advanced simply and easily, and a high molecular weight polyricinoleic acid can be synthesized efficiently.

Further, the viscosity adjusting agent for lubrication composed of a ricinoleic acid (co) polymer synthesized by the above-mentioned method and having a weight average molecular weight measured by GPC of 10,000 or more should be added to the lubricating oil composition. Thus, excellent biodegradability can be imparted to the lubricating oil composition together with viscosity characteristics (viscosity index improving effect) and friction characteristics.
[Lubricating oil composition]
In the lubricating oil composition according to the present invention, the weight ratio of the (A) base oil to the (B) ricinoleic acid (co) polymer (weight of (A) / weight of (B)) is 70/30 to It is 99.5 / 0.5, preferably 75/25 to 99/1, and more preferably 80/20 to 97/3. Within such a range, the base oil (A) and the ricinoleic acid (co) polymer (B) are contained in the lubricating oil composition by including the base oil (A) and the ricinoleic acid (co) polymer (B). Good compatibility is obtained, and a thickening effect is imparted to the lubricating oil composition. Further, even under room temperature conditions, the lubricating oil composition can exhibit an appropriate viscosity index, and therefore has good fluidity. Furthermore, when the base oil (A) is a vegetable oil, the low temperature storage stability of the lubricating oil composition can be improved.

Further, since an appropriate lubricating performance can be imparted to the lubricating oil composition in an intermediate temperature range (room temperature to 50 ° C.), the kinematic viscosity (based on ASTM D445) at 40 ° C. of the lubricating oil composition according to the present invention is 50 preferably to ~ 300mm ² / s, and even more preferably from 80 ~ 200mm ² / s.

In addition, since the lubricating oil composition can be provided with appropriate lubricating performance in a high temperature range (50 ° C. to 100 ° C.), the kinematic viscosity at 100 ° C. (according to ASTM D445) of the lubricating oil composition according to the present invention is: The thickness is preferably 10 to 100 mm ² / s, and more preferably 15 to 50 mm ² / s.

In addition, since the lubricating oil composition can be used in a wide temperature range and appropriate lubricity can be maintained at each temperature, the viscosity index (based on ASTM D2270) of the lubricating oil composition according to the present invention is 180. Is preferably from 250 to 250, and more preferably from 200 to 250.

In addition, when the lubricating oil composition is naturally scattered (leakage), it is required to be quickly decomposed (biodegraded) in the natural environment, so that the modified MITI test of the lubricating oil composition according to the present invention is performed. The biodegradation rate based on the method “OECD301C” is preferably 60% or more.
[Additive (C)]
In addition to the base oil (A) and the ricinoleic acid (co) polymer (B), the lubricating oil composition according to the present invention is used for the purpose of improving oxidation stability, rust prevention, extreme pressure, defoaming, etc. Accordingly, it is preferable to include an additive (C).

Such an additive (C) is one or more selected from the group consisting of antioxidants, extreme pressure agents, rust inhibitors, metal deactivators, antiwear additives, antifoaming agents and detergent-dispersants. It is preferable that

Further, the total amount of the additive (C) can be appropriately blended within a range not impairing the object of the present invention, but is 0.05 to 25% by weight with respect to 100% by weight of the lubricating oil composition. It is preferable.
[Antioxidant]
As the antioxidant used in the lubricating oil composition of the present invention, known antioxidants can be used. Specifically, di (alkylphenyl) amine (alkyl group has 4 to 20 carbon atoms), phenyl-α -Naphthylamine, alkyldiphenylamine (alkyl group has 4 to 20 carbon atoms), N-nitrosodiphenylamine, phenothiazine, N, N'-dinaphthyl-p-phenylenediamine, acridine, N-methylphenothiazine, N-ethylphenothiazine, dipyridylamine, Amine antioxidants such as diphenylamine, phenolamine, 2,6-di-t-butyl-α-dimethylaminoparacresol, 2,6-di-t-butylparacresol, 4,4′-methylenebis (2, 6-di-t-butylphenol), 2,6-di-t-butyl-4-N, N-dimethyl Phenolic antioxidants such as minomethylphenol, 2,6-di-t-butylphenol, dioctyldiphenylamine, organic iron salts such as iron octoate, ferrocene, iron naphthoate, cerium naphthoate And organic metal compound-based antioxidants such as organic cerium salts such as cerium toluene and organic zirconium salts such as zirconium octoate. Moreover, although antioxidant may be used independently, it can also be used in combination of 2 or more types.
(Extreme pressure agent)
As the extreme pressure agent used in the lubricating oil composition of the present invention, known extreme pressure additives can be used. Specifically, chlorine compounds such as chlorinated paraffin, chlorinated diphenyl, and chlorinated fatty acid; Sulfur compounds such as fatty acids, sulfurized fatty acid esters, sulfurized animal oils, sulfurized vegetable oils, dibenzyl disulfide, synthetic polysulfides, amine salts or alkali metal salts of alkylthiopropionic acids, and amine salts or alkali metal salts of alkylthioglycolic acids; phosphoric acid Esters, acidic phosphates, amine salts of acidic phosphates, and phosphorus compounds such as chlorinated phosphates and phosphites, zinc dialkyldithiophosphates or zinc diallyldithiophosphates, organomolybdenum compounds, naphthenic acids Metal soap such as lead, organic borate Le and metal salts thereof and amine salts, organic phosphonic acids and their metal salts or amine salts.

One or two or more extreme pressure agents can be added to the lubricating oil composition of the present invention, and the combination of extreme pressure additives used when two or more extreme pressure agents are added has the desired characteristics of the resulting lubricating oil composition. It can be arbitrarily combined so that it can have.

The content of the extreme pressure agent in the lubricating oil composition is preferably 0.5 to 10 parts by weight, preferably 2 to 8 parts by weight, with respect to 100 parts by weight of the base oil (A). Further preferred.
[anti-rust]
Examples of the rust inhibitor used in the lubricating oil composition of the present invention include petroleum sulfonate, alkylbenzene sulfonate, dinonylnaphthalene sulfonate, alkenyl succinic acid ester, and polyhydric alcohol ester.
[Metal corrosion inhibitor]
Examples of the metal corrosion inhibitor used in the lubricating oil composition of the present invention include benzotriazole and its derivatives, and thiazole compounds.
[Antiwear additive]
Examples of the antiwear additive include phosphorus compounds, organic molybdenum compounds, fatty acid ester compounds, and aliphatic amine compounds.

Examples of antiwear additives for phosphorus compounds include zinc alkyldithiophosphates, phosphoric acid, phosphorous acid, phosphoric acid monoesters, phosphoric acid diesters, phosphoric acid triesters, phosphorous acid monoesters, Examples thereof include phosphoric acid diesters, phosphite triesters, salts of (phosphite) esters, and thiophosphoric acid, thiophosphorous acid or esters thereof, and mixtures thereof. Among these, zinc alkyldithiophosphate is preferably used, and usually contains a hydrocarbon group having 2 to 30 carbon atoms, preferably 3 to 20 carbon atoms. Examples of the hydrocarbon group having 2 to 30 carbon atoms include an alkyl group, a cycloalkyl group, an alkylcycloalkyl group, an alkenyl group, an aryl group, an alkylaryl group, and an arylalkyl group.

Examples of the organic molybdenum compound as the antiwear additive include molybdenum dithiocarbamate, molybdenum dithiophosphate, and molybdate amine salt. Molybdenum dithiocarbamate is particularly preferable.
[Defoaming agent]
As the antifoaming agent used in the lubricating oil composition of the present invention, known antifoaming agents can be used. Examples thereof include silicon-based antifoaming agents such as dimethylsiloxane and silica gel dispersion; alcohols and ester-based antifoaming agents. Can be mentioned.
[Cleaning dispersant]
As the detergent dispersant used in the lubricating oil composition of the present invention, known detergent dispersants can be used. For example, metal sulfonates such as calcium sulfonate, magnesium sulfonate, barium sulfonate, thiophosphonate, phenate, salicylate, succinimide , Benzylamine, succinic acid ester and the like.
[Method for producing lubricating oil composition]
The lubricating oil composition of the present invention is obtained by mixing and kneading a base oil (A), a predetermined ricinoleic acid (co) polymer (B), and, if necessary, an additive (C) at a predetermined ratio.

Here, when mixing and kneading the base oil (A), the ricinoleic acid (co) polymer (B) and, if necessary, the additive (C), these components are mixed simultaneously or in any order. -You may add to a kneading apparatus.

Also, as a mixing / kneading means, a known mixing / kneading apparatus such as a tank blend method or an auto blender method can be used.

In order to improve the uniformity of each component in the lubricating oil composition, it is preferable to mix and knead each component after heating to 60 to 80 ° C. or while heating.
[Use of lubricating oil composition]
The lubricating oil composition according to the present invention is very useful as a lubricating oil composition for each application because it has good viscosity characteristics and friction characteristics and is excellent in biodegradability.

Specific applications include, for example, gear oil, hydraulic oil, engine oil (two-cycle engine oil, gasoline engine oil, diesel engine oil, etc.), grease, cutting oil, grinding oil, punching oil, drawing oil, press oil , Drawing oil, rolling oil, forging oil, sliding oil, electrical insulation oil, turbine oil, gear oil, air compressor oil, compressor oil, vacuum pump oil, bearing oil, heat medium oil, mist oil, refrigerator oil, lock Drill oil is preferred.

Next, although an Example is shown and this invention is demonstrated further in detail, this invention is not limited by these. The measurement conditions and production conditions for the weight average molecular weight of the ricinoleic acid (co) polymer, and the evaluation criteria for the physical properties of the lubricating oil composition are shown below.
(Weight average molecular weight)
The weight average molecular weight of the ricinoleic acid (co) polymer was calculated in terms of polystyrene by molecular weight measurement using GPC.
The apparatus and measurement conditions used for the measurement are shown below.
Pump: 880-PU (JASCO Corporation)
Column: Shodex K-804L + K-800D (Showa Denko KK)
Detector: 830-RI (JASCO Corporation)
Recorder: 807IT (JASCO Corporation)
Eluent: Chloroform (including 1% ethanol)
Measurement conditions: flow rate 1.0 ml / min
: Injection volume 200 μl (2 mg / ml)
: Temperature 25 ℃
Standard sample for calibration curve: Special polystyrene standard (Chemco Chemical Co., Ltd.) (Mw = 600,000, Mw = 50,000, Mw = 17,500, Mw = 9000, Mw = 2,200, Mw = 906) )
[Production Example 1] (Production of polyricinoleic acid P-1)
Polyricinoleic acid (P-1) was synthesized in a batch manner using a 10-ml test tube equipped with a stirrer.

Specifically, first, 500 mg of methyl ricinoleate (manufactured by Sigma-Aldrich Sakai Japan Co., Ltd.) and 250 mg of immobilized lipase derived from Burkholderia cepacia (Wako Chemical Co., Ltd., Lipase PS-C Amano II) were placed in a test tube. Stirring reaction was carried out at 3 ° C. for 3 days. However, in order to remove the condensate (methanol) from the reaction system, the reaction was carried out by attaching a tube filled with molecular sieve 4A to the top of the test tube.

After the reaction for 3 days, 8 ml of chloroform was added to the obtained polyricinoleic acid crude product (including immobilized lipase) to dissolve polyricinoleic acid, and then insoluble in chloroform by filtration. The immobilized lipase was removed. Chloroform was concentrated with an evaporator to prepare about 1 ml of concentrated polyricinoleic acid. The obtained polymer solution is dropped into methanol, which is a poor solvent, to precipitate high molecular weight polyricinoleic acid and decantate to give 400 mg of the desired polyricinoleic acid (weight average molecular weight 40,600) as a precipitate. Got as. By repeating the same operation, 5 g of polyricinoleic acid (P-1) was prepared. The polymerization conditions and the weight average molecular weight of the obtained polymer are shown in Table 1.

[Production Example 2] (Production of polyricinoleic acid P-2)
Polyricinoleic acid (P-2) was synthesized under the same conditions as P-1, except that the polymerization time was changed. The polymerization conditions and the weight average molecular weight of the obtained polymer are shown in Table 1.

[Production Example 3] (Production of polyricinoleic acid P-3)
Polyricinoleic acid (P-3) was synthesized under the same conditions as P-1, except that the amount of enzyme used as a catalyst and the polymerization time were changed. The polymerization conditions and the weight average molecular weight of the obtained polymer are shown in Table 1.

[Production Example 4] (Production of polyricinoleic acid P-4)
Polyricinoleic acid (P-4) was synthesized under the same conditions as P-3 except that the immobilized lipase PS-C (trade name) used as the catalyst was changed to the immobilized lipase PS-D (trade name). did. The polymerization conditions and the weight average molecular weight of the obtained polymer are shown in Table 1.

[Production Example 5] (Production of ricinoleic acid copolymer P-5)
The same as P-3, except that the monomer species used as a raw material was changed from a ricinoleic acid methyl ester alone to a monomer blend (equimolar charge ratio) consisting of ricinoleic acid methyl ester and 12-hydroxystearic acid methyl ester. Under the conditions, polyricinoleic acid (P-5) was synthesized. The polymerization conditions and the weight average molecular weight of the obtained polymer are shown in Table 1.

* 1: Enzyme amount (wt%) indicates the amount of enzyme used when the raw material (monomer type) is 100 wt%.
[Properties of base oil]
Table 2 shows the properties of the following base oils used in Examples and Comparative Examples.

Rapeseed oil: MP Biomedical DIDA (diisodecyl adipate): Daihachi Chemical Industries H-334R (neopentyl polyol fatty acid ester): NOF Corporation

[Evaluation criteria]
Hereinafter, (i) storage stability, (ii) viscosity characteristics (kinematic viscosity), (iii) viscosity characteristics (viscosity index), (vi) friction characteristics and (v) biodegradability of the lubricating oil composition will be described. Show.
[(I) Storage stability]
10 g of the lubricating oil composition obtained in the examples and comparative examples was placed in a 20 ml screw mouth bottle, heated at 50 ° C. for 30 minutes, left at room temperature, and then at 25 ° C., 0 ° C., −5 ° C. The compatibility (fluidity, crystallization) as storage stability was evaluated based on the following criteria.
○: The components of the lubricating oil composition are uniformly dispersed and not separated.
(Triangle | delta): Although each component of a lubricating oil composition is not isolate | separated, the microparticles | fine-particles crystallized slightly are seen.
X: Each component of the lubricating oil composition is separated, and crystal solidified fine particles are observed.
[(Ii) Viscosity characteristics (kinematic viscosity)]
Kinematic viscosity: Kinematic viscosities at 40 ° C. and 100 ° C. were measured based on ASTM D445.
[(Iii) Viscosity characteristics (viscosity index)]
Viscosity index: The viscosity index was determined based on ASTM D2270.
[(Vi) Friction characteristics]
Using an Optimol SRV friction and wear tester, the friction coefficient (maximum and minimum) and the wear scar depth at a load of 200 N and a temperature of 80 ° C. were measured by a ball-on-disk (steel ball / steel disk) method. .
[(V) Biodegradability]
The biodegradation rate was measured in accordance with the modified MITI test method “OECD301C”. The Eco Mark certification standard revised in July 1998 requires the biodegradation rate to be 60% or more.
[Example 1]
As polyricinoleic acid (P-1) and base oil, the weight ratio of rapeseed oil to polyricinoleic acid (P-1) (weight of (P-1) / weight of rapeseed oil) is 97/3. The rapeseed oil was mixed to prepare a lubricating oil composition. The physical properties (compatibility, viscosity characteristics, friction characteristics) of the obtained lubricating oil composition were evaluated based on the above evaluation criteria. The results are shown in Table 3.

[Example 2]
As polyricinoleic acid (P-1) and base oil, the weight ratio of rapeseed oil to polyricinoleic acid (P-1) (weight of (P-1) / weight of rapeseed oil) is 95/5. A lubricating oil composition was prepared in the same manner as in Example 1 except that rapeseed oil% was mixed, and the physical properties were evaluated. The results are shown in Table 3.

Example 3
As polyricinoleic acid (P-1) and base oil, the weight ratio of rapeseed oil to polyricinoleic acid (P-1) (weight of (P-1) / weight of rapeseed oil) is 90/10. A lubricating oil composition was prepared in the same manner as in Example 1 except that rapeseed oil was mixed, and the physical properties were evaluated. The results are shown in Table 3.
Example 4
A lubricating oil composition was prepared in the same manner as in Example 1 except that polyricinoleic acid (P-1) was changed to polyricinoleic acid (P-2), and physical properties were evaluated. The results are shown in Table 3.
Example 5
A lubricating oil composition was prepared in the same manner as in Example 2 except that polyricinoleic acid (P-1) was changed to polyricinoleic acid (P-2), and physical properties were evaluated. The results are shown in Table 3.
Example 6
A lubricating oil composition was prepared in the same manner as in Example 3 except that polyricinoleic acid (P-1) was changed to polyricinoleic acid (P-2), and physical properties were evaluated. The results are shown in Table 3.
Example 7
A lubricating oil composition was prepared in the same manner as in Example 1 except that polyricinoleic acid (P-1) was changed to polyricinoleic acid (P-3), and physical properties were evaluated. The results are shown in Table 3.
Example 8
A lubricating oil composition was prepared in the same manner as in Example 2 except that polyricinoleic acid (P-1) was changed to polyricinoleic acid (P-3), and physical properties were evaluated. The results are shown in Table 3.
Example 9
A lubricating oil composition was prepared in the same manner as in Example 3 except that polyricinoleic acid (P-1) was changed to polyricinoleic acid (P-3), and physical properties were evaluated. The results are shown in Table 3.
Example 10
A lubricating oil composition was prepared in the same manner as in Example 2 except that polyricinoleic acid (P-1) was changed to polyricinoleic acid (P-4), and physical properties were evaluated. The results are shown in Table 3.
Example 11
A lubricating oil composition was prepared in the same manner as in Example 2 except that polyricinoleic acid (P-1) was changed to ricinoleic acid copolymer (P-5), and physical properties were evaluated. The results are shown in Table 3.

Example 12
A lubricating oil composition was prepared in the same manner as in Example 5 except that rapeseed oil was changed to synthetic ester DIDA (diisodecyl adipate) as a base oil, and physical properties were evaluated. The results are shown in Table 3.
Example 13
A lubricating oil composition was prepared in the same manner as in Example 5 except that rapeseed oil was changed to synthetic ester H-334R (neopentyl polyol fatty acid ester) as a base oil, and physical properties were evaluated. The results are shown in Table 3.
[Comparative Example 1]
A lubricating oil composition was prepared in the same manner as in Example 1 except that no viscosity modifier was added to the rapeseed oil as the base oil, and the physical properties were evaluated. The results are shown in Table 4.
[Comparative Example 2]
Except for changing polyricinoleic acid (P-1) to Aclove 728 (manufactured by Sanyo Kasei Co., Ltd .: mineral oil 40-30%, alkyl methacrylate copolymer 60-70%), a commercially available polymethacrylate viscosity modifier. Prepared a lubricating oil composition in the same manner as in Example 2, and evaluated the physical properties. The results are shown in Table 4.
[Comparative Example 3]
Other than changing polyricinoleic acid (P-1) to Sunlub 1502 (manufactured by Sanyo Kasei Co., Ltd .: mineral oil 30-40%, alkyl methacrylate copolymer 60-70%), a commercially available polymethacrylate viscosity modifier Prepared a lubricating oil composition in the same manner as in Example 2, and evaluated the physical properties. The results are shown in Table 4.
[Comparative Example 4]
Other than changing polyricinoleic acid (P-1) to Sunlube 1703 (manufactured by Sanyo Chemical Co., Ltd .: mineral oil 35-45%, alkyl methacrylate copolymer 55-65%), a commercially available polymethacrylate viscosity modifier Prepared a lubricating oil composition in the same manner as in Example 2, and evaluated the physical properties. The results are shown in Table 4.
[Comparative Example 5]
A lubricating oil composition was prepared in the same manner as in Example 12 except that polyricinoleic acid (P-2) was changed to a commercially available polymethacrylate viscosity modifier include 728, and physical properties were evaluated. The results are shown in Table 4.
[Comparative Example 6]
A lubricating oil composition was prepared and physical properties were evaluated in the same manner as in Example 13 except that polyricinoleic acid (P-2) was changed to Acube 728, which is a commercially available polymethacrylate viscosity modifier. The results are shown in Table 4.
[Comparative Example 7]
A lubricating oil composition was prepared and the physical properties were evaluated in the same manner as in Example 12 except that polyricinoleic acid (P-2) was changed to a commercially available polymethacrylate viscosity modifier Sunlube 1502. The results are shown in Table 4.
[Comparative Example 8]
A lubricating oil composition was prepared in the same manner as in Example 13 except that polyricinoleic acid (P-2) was changed to Sunlube 1502, which is a commercially available polymethacrylate viscosity modifier, and the physical properties were evaluated. The results are shown in Table 4.
[Comparative Example 9]
A lubricating oil composition was prepared in the same manner as in Example 12 except that polyricinoleic acid (P-2) was changed to a commercially available polymethacrylate viscosity modifier Sunlube 1703, and physical properties were evaluated. The results are shown in Table 4.
[Comparative Example 10]
A lubricating oil composition was prepared in the same manner as in Example 13 except that polyricinoleic acid (P-2) was changed to Sunlube 1703, which is a commercially available polymethacrylate viscosity modifier, and the physical properties were evaluated. The results are shown in Table 4.

Claims

(A) a base oil and (B) a ricinoleic acid (co) polymer having a weight average molecular weight of 10,000 or more as measured by GPC (gel permeation chromatography), and (A) and (B) A lubricating oil composition having a weight ratio (weight of (A) / weight of (B)) of 70/30 to 99.5 / 0.5.
The lubricating oil composition according to claim 1, wherein the base oil is a vegetable oil and / or a synthetic ester.
The lubricating oil composition according to claim 2, wherein the synthetic ester is a diester or a polyol ester.
The lubricating oil composition according to claim 3, wherein the synthetic ester is an aliphatic diester or an aliphatic polyol ester.
The lubricating oil composition according to any one of claims 1 to 4, wherein the ricinoleic acid (co) polymer has a weight average molecular weight of 10,000 to 300,000.
In addition to (A) and (B), the lubricating oil composition comprises an antioxidant, an extreme pressure agent, a rust inhibitor, a metal deactivator, an antiwear additive, an antifoaming agent and a cleaning dispersant. The lubricating oil composition according to any one of claims 1 to 5, comprising at least one additive (C) selected from:
The lubricating oil composition according to any one of claims 1 to 6, wherein the biodegradation rate measured by the modified MITI test method OECD301C method is 60% or more.
A gear oil comprising the lubricating oil composition according to any one of claims 1 to 7.
A hydraulic oil comprising the lubricating oil composition according to any one of claims 1 to 7.
An engine oil comprising the lubricating oil composition according to any one of claims 1 to 7.
A grease comprising the lubricating oil composition according to any one of claims 1 to 7.
A metal working oil comprising the lubricating oil composition according to any one of claims 1 to 7.
A viscosity modifier for a lubricating oil comprising a ricinoleic acid (co) polymer having a weight average molecular weight of 10,000 or more as measured by GPC (gel permeation chromatography).