JPH0587117B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a fluid composition for traction drives, and more particularly to a fluid composition for traction drives that has excellent traction coefficients and high-temperature properties. BACKGROUND TECHNOLOGY In the power transmission section of a traction drive device such as a ball & cone type, cone & ring type, wheel & disc type, chain & sheave type, toroidal type, or planetary roller type, the rolling contact surface Since power is transmitted using the rolling friction created by the hardening of the lubricating oil film, the lubricant used there, that is, the traction drive fluid, must have excellent power transmission ability, that is, a high traction coefficient. is required. At the same time, the traction drive fluid is exposed to extremely high temperature conditions when the traction drive device operates at high speeds, so in order to form an oil film on the friction surface even under high temperature conditions, it is necessary to have high temperature characteristics. It is required to have a small amount of evaporation loss and a certain level of viscosity even at high temperatures. Conventionally, regarding traction drive fluid, for example, Japanese Patent Publication No. 46-338, No. 46-339,
No. 47-7664, No. 48-29715, No. 48-42067,
No. 48-42068, No. 53.-36105, No. 58-12319
No. 58-27838, No. 60-1353, No. 60-1354
No. 60-19951, No. 60-43391, No. 60-
Various compounds have been proposed in Patent No. 43392 and many other patents and documents. Problems to be Solved by the Invention However, the known traction drive fluids listed above have not been put into practical use due to reasons such as difficulty in obtaining raw materials, complicated manufacturing methods, and unsuitable traction coefficients for practical use. 2,4-dicyclohexyl-2-methylpentane, which was proposed in Japanese Patent Publications No. 53-36105 and No. 58-12319, is considered to be practical, and may be used as a fluid as it is or be expanded to this. It is only used as a grease by blending it with an agent. However, although this 2,4-dicyclohexyl-2-methylpentane has an excellent traction coefficient, it has the drawbacks of high evaporation loss and low viscosity under high temperature conditions. The present inventors have conducted extensive research to overcome the drawbacks of the conventionally known traction drive fluids as described above, and as a result, a composition containing compounds having specified structures and properties in a specific ratio has been developed. The present inventors have discovered that this fluid has excellent performance as a drive fluid, and have completed the present invention. An object of the present invention is to provide a fluid composition for a traction drive that has a high traction coefficient and excellent high-temperature properties, that is, has low evaporation loss under high-temperature conditions and excellent viscosity properties. Means for Solving the Problems The present invention provides a polymeric polymer at 40°C obtained by homopolymerizing or copolymerizing at least one of () (A) squalane and (B) an olefin having 3 to 12 carbon atoms. one or more chain hydrocarbon compounds selected from the group consisting of polyolefin oils having a kinematic viscosity of 2 to 40 cSt and an average molecular weight of 100 to 500, 20 to 80% by weight, and () General formula

[Formula, n represents an integer of 0 or 1, R ₁ and R ₂ are R ₂ = CH 3 when R 1 = H, and R ₂ = CH ₃ when R ₁ = CH ₃
Each group represents a group in which R ₂ =H. The present invention provides a fluid composition for traction drive, characterized in that it is made by mixing 80 to 20% by weight of polycyclohexyl alkane represented by: Hereinafter, the content of the present invention will be explained in more detail. In the present invention, the component () is obtained by homopolymerizing or copolymerizing at least one of (A) squalane and (B) an olefin having 3 to 12 carbon atoms, and has a kinematic viscosity of 2 at 40°C. One or more chain hydrocarbon compounds selected from the group consisting of polyolefin oils having a weight of ~40 cSt and an average molecular weight of 100 to 500. (A) Squalane here means 2, 6, 10,
15,19,23-hexamethyltetracosane (chemical formula
It is a colorless, transparent, tasteless and odorless liquid whose main component is a saturated chain hydrocarbon called C ₃₀ H ₆₂ ).Industrially, squalene is obtained by separating and refining fish oil such as shark liver oil or vegetable oil such as olive oil. Furthermore, acetylene can be produced by hydrogenation under high temperature and high pressure using a hydrogenation catalyst, and by decomposition of natural gas and geranylacetone (which is synthesized from isoprene), which is available as a raw material for isophytol synthesis. It is obtained by hydrogenolyzing the reaction product of 1,3-butadiyne, which is produced as a by-product. In addition, (B) polyolefin oil here refers to a homopolymerization or copolymerization of at least one olefin having 3 to 12 carbon atoms, specifically, for example, propylene, butene, hexene, octene, decene, dodecene, etc. Kinematic viscosity 2~
It refers to polyolefin oil with an average molecular weight of 40cSt (@40℃) and 100 to 500, and specifically includes polypropylene, polybutene, polyisobutylene, polyhexene, polyoctene, polydecene, polydodecene, and mixtures thereof having the above properties. It will be done. In addition to the above-mentioned properties, the polyolefin oil should also have a temperature below -30°C, preferably -40°C.
It is desirable that the pour point is below ℃. The manufacturing method of this polyolefin oil is well known to those skilled in the art, and includes aluminum chloride, aluminum chloride-aluminum bromide system, aluminum chloride-aluminum bromide system,
Cationic polymerization using so-called Friedel-Crafts catalysts such as ester, aluminum bromide, aluminum bromide-hydrogen bromide, magnesium chloride, boron fluoride, boron fluoride-alcohol, or their complex compounds, etc. Any method can be used in the present invention as long as it satisfies the above properties, such as by radical polymerization using a peroxide or a Ziegler catalyst. Furthermore, in the present invention, a hydrogenated polyolefin oil obtained by hydrogenating the double bonds contained in the above-mentioned polyolefin oil using a known method such as a nickel or nickel molybdate catalyst can also be used. Furthermore, as the component () of the present invention, the above (A)
It is also possible to use a mixture of squalane and (B) polyolefin oil in any proportion. On the other hand, the component () as used in the present invention refers to the general formula

It is a polycyclohexyl alkane represented by In the above formula, n represents an integer of 0 or 1, and R ₁
and R ₂ represent a group in which R ₂ =CH ₃ when R ₁ =H, and R ₂ =H when R ₁ =CH ₃ . This component (), polycyclohexylalkane, is produced by, for example, polymerizing α-methylstyrene or thermally decomposing poly-α-methylstyrene to obtain triphenylalkane or tetraphenylalkane, and then These can be produced by nuclear hydrogenation. Specifically, for example, in the polymerization of α-methylstyrene, a solid acid catalyst such as acid clay, activated clay, silica-alumina, montmolinite type viscosity, or silica gel is used, and an oxygen-containing catalyst such as water, dihydric alcohol, or ether is used. This reaction can be easily carried out by using a compound as a reaction regulator and reacting α-methylstyrene under heating. In addition, the nuclear hydrogenation reaction is performed by using a nuclear hydrogenation catalyst such as nickel, nickel-diatomaceous earth, Raney-nickel, platinum, platinum-alumina, rhodium, rhodium-alumina, etc. This can be easily done by contacting with hydrogen. Depending on the conditions, the polycyclohexylalkane obtained by the above method may have a structure other than the component () of the present invention (dicyclohexylalkane,
Pentacyclohexylalkanes, cyclic compounds, etc.) may also be mixed in as by-products, so if necessary, the target compound can be extracted by separation operations such as distillation. In the traction drive fluid composition of the present invention, the mixing ratio of components () and () is as follows:
The proportion of component () is 80 to 20% by weight, preferably 70 to 30% by weight, relative to 20 to 80% by weight, preferably 30 to 70% by weight of component (). If the mixing ratio of component () is less than the above range, the viscosity of the composition becomes too high, and in particular, component () alone is semi-solid at room temperature and cannot be put to practical use. On the other hand, if the mixing ratio of component () exceeds the above range, the high temperature properties and traction coefficient of the composition will decrease, which is not preferable. In the present invention, a traction drive fluid with excellent various performances can be obtained by mixing the above-mentioned components () and () in a specific ratio, but the 2,4- It can also contain dicyclohexyl-2-methylpentane. The content of this 2,4-dicyclohexyl-2-methylpentane is arbitrary, but usually 100 parts by weight or less per 100 parts by weight of polycyclohexylalkane, which is the component ().
Preferably it is 50 parts by weight or less. When this 2,4-dicyclohexyl-2-methylpentane is used in combination, the components () and () of the present invention are mixed to obtain the fluid composition for traction drive according to the present invention, and then 2,4-dicyclohexyl-2-methylpentane is used. -dicyclohexyl-2-methylpentane may be mixed. Furthermore, as mentioned above, when producing component () by polymerizing α-methylstyrene, depending on the reaction conditions, in addition to component (), 2,4-dicyclohexyl-
Since 2-methylpentane is also produced as a by-product, the by-produced 2,4-dicyclohexyl-2-methylpentane may be mixed with component () in the form of a mixture with component () without being separated and removed. Furthermore, as mentioned above, when producing component () by polymerizing α-methylstyrene, depending on the reaction conditions, a cyclic compound (α-
Nuclear hydrogenated products of cyclic dimers, cyclic trimers, and cyclic tetramers of methylstyrene may also be produced as by-products, but these cyclic compounds can also be used in the process of the present invention to the extent that they do not impair the effects of the present invention. It may be included in the fluid composition for shock driving. Furthermore, various commonly used lubricating oil additives can be added to the traction drive fluid composition of the present invention, if necessary. Specifically, for example, hindered phenols such as 2,6-di-t-butyl-p-cresol, aromatic amines such as phenyl-α-naphthylamine, organometallic compounds such as zinc dialkyldithiophosphate, sulfides, and disulfides. Antioxidants such as sulfur compounds such as carboxylic acids, sulfonic acids, phosphates, amines, alcohols, rust inhibitors such as esters, organic sulfur compounds, organic halogen compounds, etc.
Organic metal salts such as zinc dialkyldithiophosphate, molybdenum dialkyldithiophosphate, and molybdenum dialkyldithiocarbamate, extreme pressure agents such as phosphate esters, polymethacrylate,
Viscosity index improvers such as polyisobutylene, antifoaming agents such as silicone oil, etc. can be added. Although the amount of these known lubricating oil additives added is arbitrary, it is usually desirable to add them so that the total amount added is 20% by weight or less, preferably 10% by weight or less, based on the total amount of the composition. . Furthermore, known organic or inorganic thickeners for greases, specifically soap-based thickeners such as lithium soap, sodium soap, calcium soap, lithium complex soap, calcium complex soap, Complex soap thickeners such as aluminum complex soaps, non-soap thickeners such as organic siloxanes, terephthalamates, polyureas, organically treated clays, and silica aerogels can be added to the traction drive fluid composition of the present invention. It can also be mixed and used as a traction grease. The amount of thickening agent mixed when used as a traction grease is arbitrary, but the content of thickening agent is usually 1 to 1% based on the total amount of the grease composition.
It is preferable to mix it so that it is 30% by weight, preferably 3 to 20% by weight. EXAMPLES OF THE INVENTION The contents of the present invention will now be explained in more detail with reference to Examples and Comparative Examples. Examples 1 to 4 and Comparative Examples 1 to 5 Traction drive fluid compositions (Examples 1 to 4) according to the present invention were obtained with the compositions shown in Table 1. In addition, each component shown in Table 1 has the following properties. () Component squalane: A substance whose main component is 2,6,10,15,19,23-hexamethyltetracosane obtained by further hydrogenating squalane obtained from shark liver oil. viscosity
18.9cSt (@40℃), pour point -65℃ or less, flash point 230
°C, average molecular weight 423. Polybutene 1: Isobutylene-1-butene copolymer obtained by low polymerization of the butane-butene fraction produced by naphtha decomposition. Kinematic viscosity 2.7cSt (@40℃), pour point -70
℃ or less, flash point 87℃, average molecular weight 220. Polybutene 2: Isobutylene-1-butene copolymer obtained by low polymerization of the butane-butene fraction produced by naphtha decomposition. Kinematic viscosity 7.5cSt (@40℃), pour point -
67.5℃, flash point 115℃, average molecular weight 280. 1-decene oligomer: A branched hydrocarbon compound obtained by low polymerization of 1-decene. Kinematic viscosity 17.5cSt (@40℃), pour point -73℃, flash point 216℃, average molecular weight 353. () Component polycyclohexylalkane: A distillate with a boiling point of 415 to 430°C (converted to normal pressure) obtained by nuclear hydrogenation of a product obtained by polymerizing α-methylstyrene using activated clay as a catalyst using a nickel catalyst, and then distilling the product. minutes, is semi-solid at room temperature (20℃),

[Chemical formula] (R ₁ = CH ₃ , R ₂ = H or R ₁ = H, R ₂ = CH ₃ ) is the main component (content 95% by weight). Examples 1-4
The following performance evaluation test was conducted on the composition, and the results are also shown in Table 1. Performance Evaluation Test [High Temperature Viscosity] The kinematic viscosity at 100°C was measured according to the kinematic viscosity test method specified in JIS K 2283.3. [Evaporation Loss] After heating at 10° C. for 100 hours according to the lubricating oil thermal stability test method specified in JIS K 2540, the evaporation loss (weight loss) of the oil was determined in weight %. [Traction coefficient] Using a four-cylinder rolling friction tester, 1500 rpm,
Measurements were made under the conditions of a load of 92.5 Kg/mm ² and a slip ratio of 2%. For comparison, the case where only component () was used (Comparative Examples 1 to 4) and the case where 2,4-dicyclohexyl-2-methylpentane, which is widely used as a traction drive fluid, were used (Comparative Example 5). ) was also subjected to the above performance evaluation test,
The results are also listed in Table 1.

【table】

[Table] Effects of the Invention As is clear from the comparison of the performance evaluation tests of the Examples in Table 1 and Comparative Examples 1 to 4, the high-temperature properties are significantly improved by blending component () compared to when component () is used alone. (increased viscosity at high temperatures and reduced evaporation loss) and also improved the traction coefficient. Component (), which cannot be put to practical use alone, works extremely effectively as a combination agent of component (). I know what you're doing. Furthermore, the compositions of Examples according to the present invention have particularly excellent high-temperature properties compared to 2,4-dicyclohexyl-2-methylpentane of Comparative Example 5, which is generally used as a traction drive fluid. Useful as a shock drive fluid.

Claims (1)

[Scope of Claims] 1 () A polymer having a kinematic viscosity of 2 to 2 at 40°C, obtained by homopolymerizing or copolymerizing at least one of (A) squalane and (B) an olefin having 3 to 12 carbon atoms. 2 to 80% by weight of one or more chain hydrocarbon compounds selected from the group consisting of polyolefin oils having an average molecular weight of 40 cSt and an average molecular weight of 100 to 500, and () general formula [formula] (where n is Indicates an integer of 0 or 1, R ₁ and R ₂ are R ₂ = CH ₃ when R 1 = H, and R ₂ = CH 3 when R ₁ = CH ₃
Each group represents a group in which R ₂ =H. ) A fluid composition for a traction drive, characterized in that it is made by mixing 80 to 20% by weight of a polycyclohexyl alkane represented by: