JP2608305B2 - Fluid for traction drive - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traction drive fluid, and more particularly, to a traction drive fluid having low viscosity and excellent traction performance over a wide temperature range from low to high temperatures. .

[Problems to be solved by conventional technology and invention]

Generally, a traction drive fluid is a fluid used for a traction drive device (friction drive device by rolling contact), for example, a continuously variable transmission for automobiles, a continuously variable transmission for industry, hydraulic equipment, and the like, and has a high traction coefficient, heat and heat. Stability against oxidation, economy, etc. are required.

By the way, the size of the traction drive device is said to be inversely proportional to the traction coefficient of the traction drive fluid used to the 0.45th power.The more the traction drive fluid with the lowest traction coefficient in the operating temperature range is, the more the traction drive fluid is used. It is said that the device can be downsized.

In recent years, reductions in the size and weight of traction drive devices have been studied mainly for automotive applications, and accordingly, traction drive fluids used in this traction drive device can withstand use under various severe conditions. Demonstrate high performance (especially high traction coefficient, low viscosity, excellent heat and oxidation stability, etc.) over a wide temperature range from low temperature to high temperature (about -30 to 140 ° C). Is required.

However, various traction drive fluids have been developed, such as Japanese Patent Publication No. 46-338 and Japanese Patent Publication No. 46-339, but none of them can satisfy the above-mentioned required characteristics. There were various problems. For example, a compound exhibiting a high traction coefficient at a high temperature has a high viscosity and a large stirring loss, so that the transmission efficiency is low, and there is also a problem in low-temperature startability. On the other hand, a compound having a low viscosity and excellent transmission efficiency has a low traction coefficient at a high temperature, and also has a too low viscosity at a high temperature, which causes trouble in lubrication of a traction transmission device.

[Means for solving the problem]

Therefore, the present inventors have solved the above-mentioned problems of the prior art,
Intensive research was conducted to develop a traction drive fluid with low viscosity and excellent performance over a wide temperature range from low to high temperatures.

As a result, by polymerizing dicyclopentadiene or dihydrodicyclopentadiene, and further hydrogenating it, a polymer hydrogenated product having a weight average molecular weight of 250 or more is blended with another traction oil to achieve the intended purpose. It has been found that a traction drive fluid having traction performance can be obtained. The present invention has been completed based on such findings.

That is, the present invention provides a traction drive fluid comprising a polymer hydrogenated dicyclopentadiene and / or dihydrodicyclopentadiene having a weight average molecular weight of 250 or more and 2 to 95% by weight. To provide.

The polymer hydrogenated product in the present invention is dicyclopentadiene (DCPD), dihydrodicyclopentadiene (DHDCPD)
It is obtained by polymerizing and hydrogenating any one or both of the above as raw materials. Here, in addition to the above-mentioned DCPD and DHDCPD, a small amount of other aliphatic olefins or aliphatic dienes may be used as the polymerization raw material and may be copolymerized therewith, but components other than the above-mentioned DCPD and DHDCPD are excluded as much as possible. It is preferable to keep it.

In the polymerization of DCPD and / or DHDCPD,
Thermal polymerization may be performed at a temperature of 200 ° C. or higher without a catalyst, or polymerization may be performed in the presence of a catalyst. Further, these polymerizations can be carried out using a solvent, if necessary.

Various catalysts can be used as the catalyst used for the polymerization of DCPD or DHDCPD, but an acidic catalyst is generally used. Specifically, clays such as activated clay and acid clay, mineral acids such as sulfuric acid, hydrochloric acid and hydrofluoric acid, organic acids such as p-toluenesulfonic acid and triflic acid, aluminum chloride, ferric chloride and chloride Lewis acids such as stannic, boron trifluoride, boron tribromide, aluminum bromide, gallium chloride, gallium bromide, and solid acids such as zeolites,
Various materials such as silica, alumina, silica / alumina, cation exchange resin, and heteropolyacid can be used, but may be appropriately selected in consideration of ease of handling, economy, and the like.
The amount used is not particularly limited, but is usually the above-mentioned DCPD or DH
0.1-100% by weight, preferably 1-20% by weight based on DCPD
Range.

In the above polymerization, a solvent is not necessarily required, but it is preferable to use a solvent in handling the polymerization raw material or catalyst during the reaction or for controlling the progress of the reaction. Such solvents include n-pentane, n-hexane, heptane, octane, nonane, decane and the like, and most of saturated hydrocarbons such as cyclopentane, cyclohexane, methylcyclohexane and decalin, as well as benzene and toluene. , Xylene and other aromatic hydrocarbons, tetralin and the like can also be used.

The conditions of such a polymerization reaction may be appropriately selected according to various situations, and cannot be uniquely determined, but are usually appropriate in a temperature range of −30 to 300 ° C. depending on the type of the catalyst and additives. The conditions are set. For example, when the catalyst is clay or zeolite, the reaction temperature is from room temperature to 300 ° C., preferably 60 ° C. or higher, and if the other catalyst is −30 to 100 ° C.
C., preferably at 0-60.degree.

Next, the thus obtained DCPD or DHDCPD polymer (including a copolymer) is hydrogenated (hydrogenated) to obtain a desired polymer hydrogenated product. The hydrogenation may be performed on the entire amount of the above-mentioned polymer, or may be performed by fractionating or fractionating a part thereof.

This hydrogenation is generally carried out in the presence of a catalyst, such as nickel, ruthenium, palladium,
A catalyst known as a so-called hydrogenation catalyst containing at least one kind of metal such as platinum, rhodium, iridium, copper, chromium, molybdenum, cobalt, and tungsten can be used. The amount of the catalyst is in the range of 0.1 to 100% by weight, preferably 1 to 10% by weight, based on the polymer.

This hydrogenation proceeds in the absence of a solvent as in the case of the above-mentioned polymerization reaction, but a solvent can also be used. In this case, n-pentane, n-hexane, heptane, octane, nonane , Decane, dodecane, etc., and most liquid saturated hydrocarbons such as cyclopentane, cyclohexane, methylcyclohexane and the like can be used. Further, any liquids such as aromatics, olefins, alcohols, ketones, and ethers can be used, and saturated hydrocarbons are particularly preferable.

The reaction temperature is usually room temperature to 300 ° C, preferably 40 to 200 ° C.
° C, and the reaction pressure can be carried out within a range from normal pressure to 200 kg / cm ² G, preferably from normal pressure to 100 kg / cm ² G, and can be carried out by the same operation as general hydrogenation. is there.

DCPD and / or DHDCPD thus generated
The polymer hydrogenated product must have a weight average molecular weight of 250 or more, preferably 250 to 4000, particularly preferably 250 to 1300. This weight average molecular weight is 2
If it is less than 50, high traction performance cannot be exhibited.

The above-mentioned polymer hydrogenated product has a different viscosity depending on the degree of polymerization, but generally has a high viscosity, so that it is used for blending with another traction oil to improve its traction coefficient. In this case, the amount of the polymer hydrogenated compound may be appropriately selected depending on the type of the polymer hydrogenated product, the type of other traction oil to be blended, and the like. It is determined in the range of 2 to 95% by weight, preferably 5 to 85% by weight, particularly preferably 5 to 60% by weight.

Further, other traction oils to be blended with the above-mentioned polymer hydrogenated product include various oils such as those conventionally used as traction drive oils and oils that have low traction performance alone and are not practically used. I can give it. For example, mineral substances such as paraffin-based mineral oil, naphthenic-based mineral oil, and intermediate-based mineral oil, alkylbenzene, polybutene, poly-α-olefin, synthetic naphthene, ester, and ether can be used in a wide range of liquid substances. Among them, alkylbenzene, polybutene and synthetic naphthene are preferred. Here, examples of the synthetic naphthene include an alkane derivative having two or more cyclohexane rings, an alkane derivative having at least one decalin ring and one or more cyclohexane rings, an alkane derivative having two or more decalin rings, a cyclohexane ring or a decalin ring. Are compounds having a structure in which two or more are directly bonded. Specific examples of such a synthetic naphthene include:
1-cyclohexyl-1-decalylethane; 1,3-dicyclohexyl-3-methylbutane; 2,4-dicyclohexylpentane; 1,2-bis (methylcyclohexyl) -2-methylpropane; 1,1-bis (methylcyclohexyl)- 2
-Methylpropane; 2,4-dicyclohexyl-2-methylpentane; limonene dimer hydrogenation; pinene dimer hydrogenation; camphene dimer hydrogenation.

The fluid for traction drive of the present invention contains a polymer hydrogenated product of DCPD and / or DHDCPD as an essential component, and is prepared by further blending another liquid material (traction oil). Antioxidant, rust inhibitor, detergent / dispersant, pour point depressant, viscosity index improver, extreme pressure agent, anti-wear additive, anti-fatigue agent, defoamer, oiliness improver,
Various additives such as a coloring agent may be used in an appropriate amount.

〔Example〕

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples.

Comparative Example 1 Into a four-necked flask of Example 2, 552 g of toluene, 27.6 g of anhydrous aluminum chloride and 12.6 g of nitromethane were added, and the mixture was cooled to 0 ° C.
While stirring with, 181.2 g of methallyl chloride was added dropwise over 2 hours, and stirring was continued for 1 hour to complete the reaction. 75 ml of water is added to this to decompose aluminum chloride,
After the oil layer was further separated, the oil layer was washed once with 200 ml of water for 1 time.
It was washed twice with 300 ml of a specified aqueous sodium hydroxide solution and dried over anhydrous magnesium sulfate.

Next, by a rotary evaporator, after distilling off the unreacted raw materials, the mixture was distilled under reduced pressure and had a boiling point of 114 to 116 ° C / 0.14 mmHg.
Of 254 g was obtained.

As a result of analysis, this fraction was found to be composed of 80% of 2-methyl-1,2-ditolylpropane and the isomerized product of 2-methyl-1,1-
Ditolylpropane was found to be 20%.

Subsequently, 250 g of this fraction was put into one autoclave, and 20 g of a nickel catalyst (N-113 manufactured by Nikki Chemical Co., Ltd.) was added.
Hydrogenation was performed at a hydrogen pressure of 70 kg / cm ² G and a temperature of 180 ° C. for 5 hours. When the catalyst was removed from the obtained reaction product and analyzed, the hydrogenation rate was 99.9% or more, and 2-methyl-1,
80% of 2-di (methylcyclohexyl) propane, 2-
Methyl-1,1-di (methylcyclohexyl) propane is 2
It was found to be 0%.

 The properties of this product were as follows.

Kinematic viscosity 13.17 cSt (40 ° C) 2.622 cSt (100 ° C) Viscosity index -30 Specific gravity (15/4 ° C) 0.8824 Pour point -47.5 ° C Refractive index (n _D ) 1.4800 140
It was measured in a temperature range of ° C. The result is shown in FIG.

Example 1 A commercially available hydrogenated petroleum resin (weight average molecular weight 540, manufactured by Exxon Chemical Co., Ltd., trade name: dicyclopentadiene (DCPD)) was added to the fluid obtained in Comparative Example 1 above. E
SCOREZ5300) was mixed at 10% by weight to obtain a fluid.

 The properties of this fluid were as follows.

Kinematic viscosity 23.15 cSt (40 ° C) 3.686 cSt (100 ° C) Viscosity index −24 Specific gravity (15/4 ° C) 0.8991 Pour point −37.5 ° C Refractive index (n _D ) 1.4861 ° C
Was measured in the temperature range of The result is shown in FIG.

Comparative Example 2 Ethylbenzene (2700 g) was placed in a glass flask having an inner volume of 5.
Add 58g of metallic sodium and 16g of potassium hydroxide, 12
While stirring at 0 ° C., a mixture of 1100 g of α-methylstyrene and 300 g of ethylbenzene was gradually added dropwise over 5 hours, and then stirred for 1 hour to carry out a reaction.

After completion of the reaction, the reaction mixture was cooled to separate and collect an oil layer. To this, 200 g of methyl alcohol was added, and the mixture was washed three times each with a 5N aqueous hydrochloric acid solution 2 and a saturated saline solution 2. Next, after drying over anhydrous sodium sulfate, unreacted ethylbenzene was distilled off using a rotary evaporator, and 1350 g of a fraction having a boiling point range of 106 to 108 ° C at 0.06 mmHg was further distilled under reduced pressure.
Obtained.

Next, 500 ml of this fraction was put into an autoclave having an internal volume of 1, and a nickel catalyst for hydrogenation (manufactured by Nikki Chemical Co., Ltd .: N-
113) Add 20g, reaction temperature 200 ℃, hydrogen pressure 50kg / cm ² G
Was hydrotreated. After the reaction, remove the catalyst,
As a result of stripping and analyzing the light components, the hydrogenation ratio was 99.9% or more, and it was confirmed that the hydrogenated product was 2,4-dicyclohexylpentane.

 The properties of this product were as follows.

Kinematic viscosity 12.05 cSt (40 ° C) 2.750 cSt (100 ° C) Viscosity index 47 Specific gravity 0.8913 Refractive index (n _D ) 1.4832 Pour point -50 ° C or less In addition, the traction coefficient of this product is reduced from 60 ° C to 14
The measurement was performed in a temperature range of 0 ° C., and the results are shown in FIG.

Example 2 The fluid obtained in Comparative Example 2 was mixed with 10% by weight of the hydrogenated petroleum resin used in Example 1 to obtain a fluid.

 The properties of the obtained fluid were as follows.

Kinematic viscosity 19.89 cSt (40 ° C) 3.736 cSt (100 ° C) Viscosity index 52 Specific gravity 0.9074 Refractive index (n _D ) 1.4899 Pour point -47.5 ° C
The measurement was performed in a temperature range of ° C., and the results are shown in FIG.

Example 3 500 g of DCPD and 8 g of a developed Raney cobalt catalyst were placed in a stainless steel autoclave of 1, and hydrogen pressure was 10 kg / c.
Hydrogenation was performed at 100 ° C. for 1 hour at m ² G. After cooling, the catalyst was filtered and analyzed. As a result, about 500 g of a liquid containing 92% of DHDCPD, 2% of DCPD and 6% of tetrahydrodicyclopentadiene was obtained.

Next, a Dimroth reflux condenser and a thermometer were attached to one three-necked flask, and the liquid containing DHDCPD as a main component was used.
500 g and 100 g of dried activated clay were added and stirred at 150 ° C. for 10 hours.

After filtering the activated clay from the reaction mixture, unreacted DHDC
The PD was distilled off, placed in a stainless steel autoclave, hydrogenated with a nickel / diatomaceous earth catalyst (N-113, manufactured by Nikki Chemical Co., Ltd.) at a hydrogen pressure of 10 kg / cm ² G at 150 ° C., and DHDCP was added.
About 200 g of a hydrogenated polymer (weight average molecular weight: 320) of the dimer or more of D was obtained.

This polymer hydrogenated product was mixed with the fluid obtained in Comparative Example 1 at 10% by weight.

 Its properties were as follows.

Kinematic viscosity 18.10cSt (40 ℃) 3.153cSt (100 ℃) Viscosity Index -35 specific gravity 0.8994 refractive index (n _D) 1.4862 Pour point -37.5 ° C. Further, the traction coefficient of the product from 60 ° C. 14
The measurement was performed in a temperature range of 0 ° C., and the results are shown in FIG.

The measurement of the traction coefficient in Examples and Comparative Examples was performed using a two-cylinder friction tester. In other words, one of the two cylinders of the same size (52 mm in diameter, 6 mm in thickness, tyco type with a radius of curvature of 10 mm on the driven side, flat type without crowning on the driven side) at a constant speed (1500 rpm)
In, the other is continuously rotated from 1500rpm to 1750rpm,
A 7kg load is applied by a spring to the contact portion between the two cylinders, and the tangential force generated between the two cylinders, that is, the traction force, is measured.
The traction coefficient was determined. This cylinder is a bearing steel SUJ-2
Mirror-finished, maximum Hertz contact pressure is 112kgf / m
It was m ^2.

In measuring the relationship between the traction coefficient and the oil temperature, the oil temperature was changed from 60 ° C to 140 ° C by heating the oil closet with a heater, and the relationship between the traction coefficient and the oil temperature at a sliding rate of 5% was measured. Is plotted.

〔The invention's effect〕

As described above, the traction drive fluid of the present invention containing a polymer hydrogenated product of DCPD or DHDCPD has a high traction coefficient over a wide temperature range from room temperature to high temperature, and improves transmission efficiency. As a result, the size and weight of the traction drive device can be reduced, the life thereof can be extended, and the output can be increased, and the traction drive device can be widely used for various mechanical products such as a continuously variable transmission for automobiles or industries, and hydraulic equipment.

Further, the above-mentioned polymer hydrogenated product can increase the traction coefficient only by blending it in a small amount with another fluid, and can provide various excellent traction drive fluids.

[Brief description of the drawings]

FIGS. 1 and 2 are graphs showing temperature changes of traction coefficients of traction drive fluids obtained in Examples and Comparative Examples.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location C10N 40:04 40:08 60:02

Claims (1)

(57) [Claims] 1. A traction drive fluid comprising a hydrogenated polymer of dicyclopentadiene and / or dihydrodicyclopentadiene having a weight average molecular weight of 250 or more in an amount of 2 to 95% by weight. .