CN1019021B - Phosphate lubricant - Google Patents

Abstract

Use as lubricants, especially for traction drives, of organophosphate esters of the general formula I:- (R<1>O)2- @-(OR<2>) I wherein each group R<1> individually represents a saturated alicyclic group, preferably cyclohexyl, optionally substituted by one or more alkyl, especially methyl groups, and R<2> represents R<1> or an alkyl or aryl group.

Description

Phosphate lubricant

This process relates to the application as some phosphate compound of lubricant, particularly their application in towing gear.

These lubricants can be used for various engineerings to be used, and is valuable especially in towing gear.Traction briefly is defined as the adhesion friction of object on its moving surface.Towing gear is such device, swinging moment is delivered to output element by the contact of nominal point or line from input element in this device, and the contact of this nominal point or line generally has tumbling action by the traction between contact member.And logical being usual to speak of traction element is to be in contact condition, generally believes to have fluid film betwixt.Nearly all towing gear all needs fluid to reduce phlegm and internal heat, avoid surface in contact abrasion and lubricating bearings and other moving parts relevant with transmission to remove.Thereby, replace metal contact with rolling between the metal, one deck introducing zone of action and the fluid film between between hardware are arranged.This fluidic characteristic has determined the limit of performance and the ability of transmission to a great extent.Most of towing gears are designed to operate with draw fluid, it is about more than 0.06 that this draw fluid preferably has drag coefficient, at 40 ℃--the range of viscosities that has in 20 ℃ the temperature range is about 4-20,000 milli handkerchief second (mpas), and have good thermostability and oxidative stability.This fluid also should not corrode common making material and have good load-carrying properties and low abrasion rate capability.

Mineral base oil is the lubricant of quite not satisfied towing gear, because generally their traction (friction) coefficient is low, this means for any fixed load of giving on the gear, and can be low by the maximum tangential force of friction wheel transmission.

Have been found that now some organophosphate is good lubricant and traction fluid.Therefore, the organophosphate that the invention provides formula I is as lubricant, particularly as the application of traction fluid

Wherein, each R ¹Base is represented the saturated fat cyclic group that is replaced arbitrarily by one or more alkyl, preferably C separately _5-7Cycloalkyl, R ²Represent R ¹Or alkyl or aryl.As R ¹Substituent alkyl on the base can be straight chained alkyl or branched-chain alkyl, and preferably contains 1-6 carbon atom, contains the combination that specially suitable physical properties and material cost are provided up to the group of 4 carbon atoms.Work as R ²When being alkyl or aryl, preferred base is C _1-6Alkyl, preferably C _4-6Branched-chain alkyl, for example, neo-pentyl, or the phenyl that has one or more alkyl to replace arbitrarily, for example, tolyl.

The organophosphate of preferred formula I is R wherein ¹Those compounds of the cyclohexyl that replaces for any alkyl.Best R ¹Be cyclohexyl or methylcyclohexyl, R ²Be cyclohexyl, methylcyclohexyl, tolyl or C _4-6Branched-chain alkyl.The ester of particularly preferred formula I is R wherein ¹And R ²Be those compounds that are selected from 2-methylcyclohexyl and 3-methylcyclohexyl respectively.

Organophosphate is known compound, thereby can prepare with known method, as in the presence of alkali (as pyridine or triethylamine), and also suitably exists under a kind of solvent, and phosphoryl chloride and suitable alcohol react and prepares.Nature, optimum reaction condition will specifically change according to used alcohol.Under the situation of hexalin and phosphoryl chloride reaction, think in dichloromethane solvent to be no more than under 25 ℃ and react that products therefrom is with the crystallization process result that purification can obtain from diethyl ether in temperature.Can use similar reaction conditions for the methylcyclohexyl analogue, and to purify with thin-film evaporator be useful.

The viscosity characteristics that it is believed that above-mentioned ester cpds is that the utmost point is applicable to for example friction drive (towing gear), in this purposes, they can with the grease thickener fusion of routine.These thickening materials can be to be commonly used to the material of thickening of mineral oil to any amount of lubricant viscosity, comprise organic and inorganic compositions, as metallic soap, synthetic polymer, organo-siloxane, carclazyte, wilkinite and colloidal silica.Aptly, the viscometric properties that be used for the compound of towing gear is like this, so that this compound can turn round at-30-150 ℃.For reaching this situation, the viscosity of the ester cpds in lubricant according to the present invention in the time of 40 ℃ at the most 1000, best 250mm ²/ s, in the time of 100 ℃ at least 1, best 3mm ²/ s is favourable.

These compounds can be used as lubricant in various engineerings are used.Because above-mentioned ester cpds shows excellent lubricating properties in traction in the transmission, thereby the present invention provides the application of these ester cpds as traction fluid particularly, and the operation of these esters as the towing gear of traction fluid is provided.

These ester cpds of the present invention itself can be used as lubricant.They can with other mix lubricant, for example mineral oil or synthetic oil, and can be with various additives, for example VI improving agent, pour point depressant, dispersion agent, purification agent, antioxidant or the like are added in these ester cpds.May use the mixture acquire a special sense to traction fluid is and polyolefine, and concrete is poly-alpha olefins, and the adulterant of polyisobutene particularly is because the existence of polymkeric substance can effectively improve the drag coefficient of liquid adulterant.The molecular weight of these polyolefin blend thing components is suitable in the 500-10000 scope, and the specific examples of suitable polyisobutene is " Hyvis ", and polyolefinic ratio can be in 0-70%(weight) change.

The following examples have illustrated the preparation of the representative compounds that the present invention is used, and their nature of friction and other physical properties also has been described simultaneously.

Embodiment I tricyclohexyl phosphate

Under the exsiccant nitrogen atmosphere, stir hexalin (751.2g, 7.5m) and pyridine (595.0g, the 7.5m) solution in methylene dichloride (3.5L), and in 1-2 hour, drip phosphoryl chloride (382.5g, 2.5m), and the temperature that keeps this reaction mixture between whole charge period is in 15-25 ℃.Add when material, continued at ambient temperature restir 18 hours, filter the mixture that obtains then, (3 * 5L) wash this organic solution and dry (at MgSO to water then ₄On).Evaporate solvent, the faint yellow heavy-gravity oil of slow solidified (730.3g) when obtaining leaving standstill in 30 ℃ in a vacuum.Should be slightly oil stir and be dissolved in the diethyl ether (750ml), and in dry ice/acetone cooling bath, stir and be cooled to-40--50 ℃.Also make it drying in 25 ℃ in a vacuum obtains tricresyl phosphate (cyclohexyl) ester (520.0g) to filtering precipitate, and it is a pale solid, fusing point 48-50 ℃.

Embodiment II tricresyl phosphate (methylcyclohexyl) ester

Under the exsiccant nitrogen atmosphere, be stirred in methyl-cyclohexanol in the methylene dichloride (10L) and (technical grade, contain isomer mixture; 2.08kg, 18.2m) and pyridine (1.44kg, solution 18.2m), and in 1.5 hours, drip phosphoryl chloride (930.2g, 6.07m), and between whole charge period with the temperature maintenance of the reaction mixture that stirs at 15-25 ℃.When adding material, continuous restir is 18 hours under envrionment temperature, filters the mixture that generates then, and water (4 * 6L) washings, and dry (at MgSO ₄On), evaporating solvent in 30 ℃ in the air at it and obtain thick product, it is a heavy-gravity oil.This thick oil is standing over night at room temperature, filter then, under KDL-4 thin-film evaporator evaporation (at 85 ℃ and 0.8mmHg(107 handkerchief)) remove pure and mild other volatile impunty of unreacted methylcyclohexyl, obtain containing the transparent toughening oil product (1.75kg) of various mixture of isomers.

Embodiment III-V

Adopt the method for embodiment II, but use respectively 2 methyl cyclohexanol, 3 methyl cyclohexanol and 4 methyl cyclohexanol (every kind suitable-and the situation of anti--mixture of isomers under) replace the methyl-cyclohexanol of technical grade, preparation has:

III-tricresyl phosphate (2-methylcyclohexyl) ester (oil)

IV-tricresyl phosphate (3-methylcyclohexyl) ester (oil)

V-tricresyl phosphate (4-methylcyclohexyl) ester (oil)

Single (aminomethyl phenyl) ester of embodiment VI phosphoric acid two (methylcyclohexyl)

Under the exsiccant nitrogen atmosphere in 15 ℃ be stirred in phosphoryl chloride in the methylene dichloride (750ml) (115.0g, 0.75m) and the mixture of cresols (cuts of isomer).(59.3g 0.75m), and keeps the temperature of reaction mixture to be lower than 20 ℃ during this is whole to drip pyridine in 20-30 minute.Under envrionment temperature, stirred the mixture 18 hours, and then the adding pyridine (118.7g, 1.5m).Mixture is cooled to 10-15 ℃, and (205.5g, 1.8m), and the temperature maintenance that makes reaction mixture during this is whole is at 15-20 ℃ adding methyl-cyclohexanol (technical grade as the embodiment II) in 30 minutes.In evening of continuously stirring, (4 * 500ml) washings and dry (on sal epsom), vaporising under vacuum goes out solvent to the mixture water then.The thick oil (315g) that generates by thin-film evaporator (150 ℃ with 0.8mmHg pressure (107 handkerchief) under) to remove volatile impunty, obtain single (aminomethyl phenyl) ester (230g) of desired phosphoric acid two (methylcyclohexyl), it is the brown oil that contains various mixture of isomers.

Two (methylcyclohexyl) the single neo-pentyl esters of embodiment VII phosphoric acid

Under the exsiccant nitrogen atmosphere in 15 ℃ of phosphoryl chloride (76.7g that are stirred in the methylene dichloride (500ml), 0.5m) solution, (44.1g, 0.5m), the temperature maintenance of chien shih reaction mixture is being lower than 20 ℃ in whole charge period to add neopentyl alcohol then in 15 minutes.Stirred the mixture 24 hours, (130.5g 1.65m) is cooled to 10-15 ℃ simultaneously to drip pyridine then.Add then methylcyclohexyl alcohol (technical grade as the embodiment II) (137.1g, 1.2m), and whole charge period the chien shih stirred mixture temperature maintenance at 10-20 ℃.Then 15-20 ℃ of following continuously stirring 18 hours, after this, the solution with water of generation (4 * 500ml) washings, dry (on sal epsom), and evaporation obtains crude product (200.3g) in a vacuum, and it is a yellow oil.Obtain two (methylcyclohexyl) the single neo-pentyl esters (131.g) of phosphoric acid with thin-film evaporator evaporation (under 150 ℃ and 0.7mmHg pressure (93 handkerchief)) the thick oil of purifying, it is the yellow toughening oil that contains various isomery object mixtures.

Embodiment VII Determination of Friction Coefficient

All frictions are measured and are all carried out on the double plate machine.The steel disk that hardens is fixed on the end of two axles so that tangentially contact mutually, and the radial force that can be applied with the 0-200kgf load is to force together these two dishes.Each dish electric motor driving.The speed of rotation difference of two dishes, making like this has a slip.

At motor and the between centers that carries lower sample the determinator that moment of friction is transmitted in indication is installed.Determinator is the gear ergometer of a band pendulum, and when transmission of power, the pendulum swing departs from its vertical equilibrium position, and the sine of the angle of inclination is exactly the size of moment.Measuring of moment is that design and specification by instrument demarcated in advance, and the moment of measurement takes advantage of the product of lower wall radius to be defined as frictional coefficient divided by radial force.

The diameter of two used dishes all is 50.0mm, on coil widely for 3mm, lower wall is wide to be 10mm.Apical axis speed is 606 rev/mins (rpm), and average tangent line (or surface) speed is 1.48 meter per second (ms ^-1).Used slip is 9.1%.

All tests are all carried out under envrionment temperature (21 ℃ ± 2 ℃).The friction reading is to provide under the load that equals 0.69,0.97,1.19 and 1.38 gpa (GPa) Hertzian stress.

The frictional coefficient of compound is shown in following table.For the fusing point of embodiment I is 48-50 ℃ compound, and these coefficients are in 21(± 2) ℃ under measure with supercooled liquid.

The kinematic viscosity character of compound is also listed in this table.

The frictional coefficient that is noted that these compounds all is good, but the frictional coefficient of the compound of embodiment III and IV is surprising good.

Claims (2)

1, the organophosphate of formula I is as the application of lubricant

R wherein ¹And R ²Be selected from 2-methyl cyclohexyl and 3-methyl cyclohexyl respectively.

2, according to the application of claim 1, wherein the organophosphate of formula I is the 3-(2-methylcyclohexyl) phosphoric acid ester or 3-(3-methylcyclohexyl) phosphoric acid ester.