High-performance ionic liquid and preparation method thereof, thiazole compound and lubricant

Abstract

The present invention relates to the technical field of grease, and specifically to a high-performance ionic liquid and a preparation method thereof, a thiazole compound and a lubricant. The ionic liquid is a thiazole-based ionic liquid, and the anion of the ionic liquid is one of tetrafluoroborate, hexafluorophosphate, trifluoromethanesulfonate or di(trifluoromethylsulfonyl)imide; the cation is an oil-soluble boric acid-modified thiadiazole, and the structure is shown in the following formula I, wherein R1 is -CH3 or -SH or -S-R3; R2 is -H or C1-C20 alkyl, ester or ether, and R3 is C1-C20 alkyl, ester or ether. The ionic liquid of the present invention can be used alone or as an additive mixed with a base oil to form a lubricant, which helps to reduce the friction and wear of equipment and reduce the corrosion caused to metals when used, and has good oxidation resistance. The preparation method of the ionic liquid is simple to operate, easy to control, and conducive to large-scale industrial production.

Description

Technical Field

[0001] The invention relates to the technical field of lubricating grease, and in particular to a high-performance ionic liquid and a preparation method thereof, a thiazole compound and a lubricant. Background Art

[0002] With the continuous development of high-tech fields, traditional lubricants can hardly meet the lubrication and protection requirements under harsh conditions (high vacuum, strong radiation, high and low temperature, high speed, high load, microgravity). People have put forward higher requirements on the comprehensive performance of lubricants. Lubricants with low vapor pressure, high stability and low-temperature fluidity have always been the goal pursued by aerospace, military industry, electronics, and computer industry due to their many advantages, especially in the lubrication of space machinery. Therefore, the research on high-performance lubricants will still be one of the urgent problems to be solved in the field of tribology.

[0003] As a type of green material, ionic liquid has the advantages of low volatility, high thermal stability, high ionic conductivity, good solubility, low melting point, high chemical stability, and large electrochemical window. It is widely used in analytical chemistry, electrochemical functional materials, synthetic chemistry, lubricants, and catalysts, and has made great progress. Because of its "designability" and "modifiability", it is expected to become an ideal, green, high-performance new lubricant. Since the 20th century, more and more scientists have conducted research on ionic liquids. Although ionic liquids have many advantages, there are still many problems. For example, the biodegradation of ionic liquids after use and the corrosion of metal friction pairs.

[0004] Traditional anti-wear additives cause corrosion to metals and cause environmental pollution, so green environmental protection and multifunctionality have become the research direction of lubricant additives. Boron additives are known as non-toxic and multifunctional new additives, mainly because of their stable chemical properties. They are an inactive additive that does not react with metals. Compared with traditional additives, they are non-corrosive and non-selective to metals and can adapt to the friction of various metal surfaces. Although these boric acid additives have good tribological properties, borates have poor oil solubility and cannot be evenly and stably dispersed in oil. Additional dispersants need to be added, but the thermal stability of dispersants is poor. Dispersants are easily thermally decomposed in high-temperature working environments, affecting the performance of lubricants. In addition, borates have poor anti-emulsification and anti-hydrolysis stability, and are increasingly unsuitable for the requirements of modern industrial production. Summary of the invention

[0005] In order to overcome the shortcomings and deficiencies in the prior art, the purpose of the present invention is to provide a high-performance ionic liquid and lubricant that can be used to solve the problem that the existing ionic liquid causes corrosion to metals during use and has insufficient oxidation resistance.

[0006] Another object of the present invention is to provide a method for preparing an ionic liquid, which is simple to operate, easy to control, and conducive to large-scale industrial production, and can produce a high-performance ionic liquid with stable product quality.

[0007] The object of the present invention is achieved by the following technical scheme: an ionic liquid, wherein the ionic liquid is a thiazolyl ionic liquid, the anion of the ionic liquid is one of tetrafluoroborate, hexafluorophosphate, trifluoromethanesulfonate or di(trifluoromethylsulfonyl)imide; the cation is an oil-soluble boric acid-modified thiadiazole, and the structure is shown in the following formula I:

[0008]

[0009] Formula I

[0010] Among them, R1 is -CH3 or -SH or -S-R3; R2 is -H or a C1-C20 alkyl group, ester group or ether group, and R3 is a C1-C20 alkyl group, ester group or ether group.

[0011] The lubricating ionic liquid of the present invention can be used alone or as an additive and mixed with a base oil to form a lubricant for use as a lubricant.

[0012] Another object of the present invention is achieved by the following technical solution: A method for preparing the above-mentioned ionic liquid comprises the following steps:

[0013] (1) long-chain alkyl methyl ester and ethylene glycol amine are mixed, KOH is used as a catalyst, and stirred to react under a nitrogen atmosphere to obtain N, N-dihydroxyethyl alkyl amide, as shown in formula II;

[0014] (2) Under nitrogen protection, thiadiazole or mercaptothiadiazole, anhydrous ethanol and 2-chloroethanol are added to a reaction container, heated in a water bath and stirred for reaction; after the reaction is completed, the mixture is cooled to room temperature, the insoluble matter is filtered, the mixture is allowed to stand for stratification, the lower layer of liquid is separated, and the mixture is washed with ether for 3-4 times, and the solvent is distilled off under reduced pressure to obtain 3-hydroxyethyl-2-mercapto-thiadiazole, as shown in Formula III;

[0015] (3) Under nitrogen protection, the compound of formula II, the compound of formula III and boric acid obtained by the reaction are added to a reaction vessel, and toluene is added to the mixture as a water carrier, and condensed and refluxed at 120-140° C. for 5-8 hours to obtain a crude product, which is purified to obtain an intermediate product as shown in formula IV;

[0016] (4) adding lithium tetrafluoroborate or lithium hexafluorophosphate or lithium trifluoromethanesulfonate or lithium bis(trifluoromethylsulfonyl)imide to the aqueous solution of the product of formula IV, stirring at room temperature for 22-26 hours, extracting with ethyl acetate after the reaction, washing with distilled water, drying over anhydrous magnesium sulfate, and distilling off the solvent under reduced pressure to obtain the target product;

[0017]

[0018]

[0019] Furthermore, in the step (1), the molar ratio of the long-chain alkyl methyl ester to ethylene glycol amine is 1:1-1.05, the reaction temperature is 80-120° C., and the reaction time is 3-8 hours.

[0020] Furthermore, in the step (1), the long-chain alkyl methyl ester is preferably but not limited to methyl butyrate.

[0021] Furthermore, in the step (2), the ratio of the thiadiazole or mercaptothiadiazole to 2-chloroethanol and anhydrous ethanol is 1 mol: 1.1-1.5 mol: 500-800 mL.

[0022] Furthermore, in the step (2), under nitrogen protection, thiadiazole or mercaptothiadiazole, anhydrous ethanol and 2-chloroethanol are added to a reaction vessel, heated in a water bath at 60-85° C., and stirred for reaction for 2-8 hours.

[0023] Furthermore, in step (3), the ratio of the compound of formula III, the compound of formula II, boric acid and toluene is 1 mol: 1-1.5 mol: 1-1.5 mol: 500-800 mL.

[0024] Furthermore, in step (4), the molar ratio of lithium tetrafluoroborate to the compound of formula IV is 1:0.8-1.

[0025] The present invention also provides a thiazole compound, the structural formula of the thiazole compound is shown in Formula V, Formula VI or Formula VII:

[0026]

[0027] Formula V

[0028]

[0029] Formula VI

[0030]

[0031] Formula VII

[0032] The above-mentioned thiazole compounds can be used as ionic liquids for lubricants to solve the problem that existing ionic liquids cause corrosion to metals during use and have insufficient antioxidant properties.

[0033] The present invention also provides a lubricant, the lubricant comprising the above-mentioned ionic liquid. The ionic liquid is added to the lubricant in a proportion of 1-15wt%. The ionic liquid can be used alone or as an additive mixed with a base oil to form a lubricant, and used as a lubricant, with an addition ratio of 1-15wt%.

[0034] Furthermore, the preparation method of the lubricant is: adding the above-mentioned ionic liquid to the base oil in proportion, heating to 60-80°C and stirring evenly, cooling to room temperature and filtering to obtain the finished product, wherein the base oil is at least one of mineral oil, synthetic oil or ester oil.

[0035] The preparation method of the ionic liquid of the present invention is simple to operate and easy to control. By controlling the ratio of various raw materials, and controlling specific steps and process parameters, an ionic liquid with excellent comprehensive performance is obtained, which helps to solve the problems of stability of the working torque of the shaft and long-term lubricity, and reduces friction and wear. The preparation method has low production cost, stable product quality, and is conducive to large-scale industrial production.

[0036] The beneficial effects of the present invention are as follows: the ionic liquid of the present invention can be used alone or as an additive mixed with a base oil to form a lubricant, which helps to reduce the friction and wear of equipment and the corrosion caused to metals when used, and has good oxidation resistance. The preparation method of the ionic liquid is simple to operate, easy to control, conducive to industrial mass production, and can produce a high-performance ionic liquid with stable product quality. DETAILED DESCRIPTION

[0037] In order to facilitate the understanding of those skilled in the art, the present invention is further described below in conjunction with embodiments, and the contents mentioned in the implementation modes are not intended to limit the present invention.

[0038] In one embodiment of the present invention, a thiadiazole-based ionic liquid, wherein the anion of the ionic liquid is one of tetrafluoroborate, hexafluorophosphate, trifluoromethanesulfonate, or di(trifluoromethylsulfonyl)imide; the cation is an oil-soluble boric acid-modified thiadiazole, and the structure is shown in the following formula I:

[0039]

[0040] Formula I

[0041] Among them, R1 is -CH3 or -SH or -S-R3; R2 is -H or a C1-C20 alkyl group, ester group or ether group, and R3 is a C1-C20 alkyl group, ester group or ether group.

[0042] In one embodiment of the present invention, a method for preparing the above-mentioned ionic liquid comprises the following steps:

[0043] (1) long-chain alkyl methyl ester and ethylene glycol amine are mixed, KOH is used as a catalyst, and stirred to react under a nitrogen atmosphere to obtain N, N-dihydroxyethyl alkyl amide, as shown in formula II;

[0044] (2) Under nitrogen protection, thiadiazole or mercaptothiadiazole, anhydrous ethanol and 2-chloroethanol are added to a reaction container, heated in a water bath and stirred for reaction; after the reaction is completed, the mixture is cooled to room temperature, the insoluble matter is filtered, the mixture is allowed to stand for stratification, the lower layer of liquid is separated, and the mixture is washed with ether for 3-4 times, and the solvent is distilled off under reduced pressure to obtain 3-hydroxyethyl-2-mercapto-thiadiazole, as shown in Formula III;

[0045] (3) Under nitrogen protection, the compound of formula II, the compound of formula III and boric acid obtained by the reaction are added to a reaction vessel, and toluene is added to the mixture as a water carrier, and condensed and refluxed at 120-140° C. for 5-8 hours to obtain a crude product, which is purified to obtain an intermediate product as shown in formula IV;

[0046] (4) adding lithium tetrafluoroborate or lithium hexafluorophosphate or lithium trifluoromethanesulfonate or lithium bis(trifluoromethylsulfonyl)imide to the aqueous solution of the product of formula IV, stirring at room temperature for 22-26 hours, extracting with ethyl acetate after the reaction, washing with distilled water, drying over anhydrous magnesium sulfate, and distilling off the solvent under reduced pressure to obtain the target product;

[0047]

[0048]

[0049] In one embodiment of the present invention, in the step (1), the molar ratio of the long-chain alkyl methyl ester to ethylene glycolamine is 1:1-1.05, the reaction temperature is 80-120° C., and the reaction time is 3-8 hours.

[0050] In one embodiment of the present invention, in step (2), the ratio of the thiadiazole or mercaptothiadiazole to 2-chloroethanol and anhydrous ethanol is 1 mol: 1.1-1.5 mol: 500-800 mL.

[0051] Furthermore, in the step (2), under nitrogen protection, thiadiazole or mercaptothiadiazole, anhydrous ethanol and 2-chloroethanol are added to a reaction vessel, heated in a water bath at 60-85° C., and stirred for reaction for 2-8 hours.

[0052] In one embodiment of the present invention, in step (3), the ratio of the compound of formula III, the compound of formula II, boric acid and toluene is 1 mol: 1-1.5 mol: 1-1.5 mol: 500-800 mL.

[0053] In one embodiment of the present invention, in step (4), the molar ratio of lithium tetrafluoroborate to the compound of formula IV is 1:0.8-1.

[0054] In one embodiment of the present invention, a lubricant includes the above-mentioned ionic liquid. The ionic liquid is added to the lubricant in a ratio of 1-15wt%. The lubricating ionic liquid of the present invention can be used alone or mixed with a base oil as an additive to form a lubricant, and used as a lubricant, with an addition ratio of 1%-15%.

[0055] Furthermore, the preparation method of the lubricant is: adding the above ionic liquid to the base oil in proportion, heating at 60-80°C, mixing and stirring evenly, cooling to room temperature and filtering to obtain the finished product. The base oil is at least one of mineral oil, synthetic oil or ester oil.

[0056] Example 1

[0057] The structure of a thiazolyl compound and a thiazolyl ionic liquid provided in this embodiment is shown in Formula V:

[0058]

[0059] Formula V

[0060] This embodiment provides a method for preparing a thiazole-based ionic liquid, the preparation method comprising the following steps:

[0061] (1) Add 0.5 mol of butyric acid and 0.5 mol of ethylene glycol amine into a reaction vessel, stir and mix, add 0.01 mol of 10% concentration KOH as a catalyst, stir and react at 110°C for 4 hours under a nitrogen atmosphere to obtain N,N-dihydroxyethyl butylamide with a yield of 75%, as shown in the following formula II. The reaction formula is as follows:

[0062]

[0063] (2) Under nitrogen protection, 0.5 mol of thiadiazole, 300 mL of anhydrous ethanol and 0.55 mol of 2-chloroethanol were added to a reaction vessel, heated in a water bath at 61°C, and stirred for reaction for 8 hours. After the reaction was completed, the reaction vessel was cooled to room temperature, the insoluble matter was filtered, and the layers were allowed to stand. The lower layer of liquid was separated, washed with ether for 4 times, and the solvent was distilled off under reduced pressure to obtain 3-hydroxyethyl-2-mercapto-5-methylthiadiazole, as shown in Formula III:

[0064]

[0065] (3) Under nitrogen protection, 0.2 mol of the compound of formula II, 0.2 mol of the compound of formula III and 0.25 mol of boric acid were added to a reaction vessel, 300 mL of toluene was added as a water carrier to the mixture, and condensed and refluxed at 120° C. for 5 h to obtain a crude product. After purification, the product was obtained as shown in formula IV:

[0066]

[0067] (4) 0.25 mol of lithium hexafluorophosphate is added to 0.2 mol of the aqueous solution of the product of formula IV, and the mixture is stirred at room temperature for 24 h. After the reaction is completed, the mixture is extracted with ethyl acetate, washed with distilled water, dried over anhydrous magnesium sulfate, and the solvent is evaporated under reduced pressure to obtain the target product, as shown in formula V.

[0068]

[0069] (5) Add the above ionic liquid into PAO 4 synthetic oil at 1 wt%, heat to 70°C and mix evenly, cool to room temperature and filter to obtain the finished product.

[0070] Example 2

[0071] The structures of a thiazolyl compound and a thiazolyl ionic liquid provided in this embodiment are shown in Formula VI:

[0072]

[0073] Formula VI

[0074] This embodiment provides a method for preparing a thiazole-based ionic liquid, the preparation method comprising the following steps:

[0075] (1) Add 0.5 mol of butyric acid and 0.5 mol of ethylene glycol amine into a reaction vessel, stir and mix, add 0.01 mol of 10% concentration KOH as a catalyst, stir and react at 110°C for 4 hours under a nitrogen atmosphere to obtain N,N-dihydroxyethyl butylamide with a yield of 68%. The reaction formula is as follows:

[0076]

[0077] (2) Under nitrogen protection, 0.5 mol of 2-thiobutyl-1,3,4-thiadiazole, 300 mL of anhydrous ethanol and 0.55 mol of 2-chloroethanol were added to a reaction vessel, heated in a water bath at 61°C, and stirred for 6 hours. After the reaction was completed, the reaction was cooled to room temperature, the insoluble matter was filtered, and the layers were allowed to stand. The lower layer of liquid was separated, washed with ether for 3-4 times, and the solvent was distilled off under reduced pressure to obtain 3-hydroxyethyl-2-mercapto-5-methylthiadiazole, as shown in Formula III:

[0078]

[0079] (3) Under nitrogen protection, 0.2 mol of the compound of formula II, 0.2 mol of the compound of formula III and 0.25 mol of boric acid were added to a reaction vessel, 300 mL of toluene was added as a water carrier to the mixture, and condensed and refluxed at 130° C. for 5 h to obtain a crude product. After purification, the product was obtained as shown in formula IV:

[0080]

[0081] (4) 0.25 mol of lithium trifluoromethanesulfonate is added to 0.2 mol of the aqueous solution of the product of formula IV, and the mixture is stirred at room temperature for 24 h. After the reaction is completed, the mixture is extracted with ethyl acetate, washed with distilled water, dried over anhydrous magnesium sulfate, and the solvent is evaporated under reduced pressure to obtain the target product.

[0082]

[0083] (5) Add the above ionic liquid into PAO 4 synthetic oil at 5 wt%, heat to 70°C and stir evenly. Cool to room temperature and filter to obtain the finished product.

[0084] Example 3

[0085] The structure of a thiazolyl compound and a thiazolyl ionic liquid provided in this embodiment is shown in Formula VII:

[0086]

[0087] Formula VII

[0088] The preparation method of the thiazole compound provided in this embodiment specifically comprises the following steps:

[0089] (1) Add 0.5 mol of butyric acid and 0.5 mol of ethylene glycol amine to a reaction vessel, stir and mix, add 0.01 mol of 10% concentration KOH as a catalyst, stir and react at 110°C for 4 hours under a nitrogen atmosphere to obtain N,N-dihydroxyethyl butylamide with a yield of 70%. The reaction formula is as follows:

[0090]

[0091] (2) Under nitrogen protection, 0.5 mol of 2-butyl thioacetate-1,3,4-thiadiazole, 300 mL of anhydrous ethanol and 0.55 mol of 2-chloroethanol were added to a reaction vessel, heated in a water bath at 60-62°C, and stirred for reaction for 4 hours. After the reaction was completed, the mixture was cooled to room temperature, insoluble matter was filtered, and the mixture was allowed to stand for stratification. The lower layer of liquid was separated, washed with ether for 4 times, and the solvent was distilled off under reduced pressure to obtain 3-hydroxyethyl-2-mercapto-5-methylthiadiazole, as shown in Formula III:

[0092]

[0093] (3) Under nitrogen protection, 0.2 mol of the compound of formula II, 0.2 mol of the compound of formula III and 0.25 mol of boric acid were added to a reaction vessel, and 300 mL of toluene was added to the mixture as a water carrier. The mixture was condensed and refluxed at 120° C. for 5 h to obtain a crude product. After purification, the product was obtained as shown in formula IV:

[0094]

[0095] (4) Add 0.25 mol of lithium bis(trifluoromethanesulfonyl)imide to 0.2 mol of the aqueous solution of the product of formula IV, stir and react at room temperature for 24 h. After the reaction is completed, extract with ethyl acetate, wash with distilled water, dry over anhydrous magnesium sulfate, and evaporate the solvent under reduced pressure to obtain the target product.

[0096]

[0097] (5) Add the above ionic liquid into mineral oil at 15 wt%, heat to 60-80°C and stir evenly. Cool to room temperature and filter to obtain the finished product.

[0098] Comparative Example 1

[0099] The lubricating oil used in this comparative example is PAO 4 synthetic oil in the prior art, and the PAO 4 synthetic oil does not contain the ionic liquid of Example 2.

[0100] Comparative Example 2

[0101] The lubricating oil used in this comparative example is the mineral oil in the prior art, and the mineral oil does not contain the ionic liquid of Example 3.

[0102] The lubricating oils prepared in Examples 1-3 and Comparative Examples 1-2 were tested for their performance, and the test data are shown in Table 1 below:

[0103]

[0104] The ionic liquid of the present invention is added to a lubricant as an additive, which helps to reduce the friction and wear of equipment and the corrosion caused to metals when used, and has good oxidation resistance and excellent comprehensive performance. The ionic liquid of the present invention can be used alone or mixed with a base oil as an additive to form a lubricant. The preparation method of the ionic liquid is simple to operate, easy to control, and is conducive to large-scale industrial production, and can produce a high-performance ionic liquid with stable product quality.

[0105] The above embodiments are preferred implementation schemes of the present invention. In addition, the present invention may also be implemented in other ways. Any obvious replacement without departing from the concept of the present invention is within the protection scope of the present invention.

Claims

1. An ionic liquid, characterized in that: The ionic liquid is a thiazolyl ionic liquid. The structural formula is shown in Formula V, Formula VI or Formula VII: Formula V Formula VI Formula VII.

2. A method for preparing the ionic liquid according to claim 1, characterized in that: The steps include: (1) 0.5 mol of butyric acid and 0.5 mol of ethylene glycol amine are added to a reaction container, stirred and mixed, and 0.01 mol of 10% concentration KOH is added as a catalyst. Under a nitrogen atmosphere, the mixture is stirred and reacted at 110° C. for 4 h to obtain N,N-dihydroxyethyl butylamide, as shown in Formula II; (2) Under nitrogen protection, 0.5 mol of thiadiazole, 300 mL of anhydrous ethanol and 0.55 mol of 2-chloroethanol were added to a reaction vessel, heated in a water bath at 61°C, and stirred for reaction for 8 hours. After the reaction was completed, the reaction vessel was cooled to room temperature, the insoluble matter was filtered, and the layers were allowed to stand for stratification. The lower layer of liquid was separated, washed with ether for 4 times, and the solvent was distilled off under reduced pressure to obtain 3-hydroxyethyl-2-mercapto-5-methylthiadiazole, as shown in Formula III; (3) Under nitrogen protection, 0.2 mol of the compound of formula II, 0.2 mol of the compound of formula III and 0.25 mol of boric acid were added to a reaction vessel, 300 mL of toluene was added to the mixture as a water carrier, and condensed and refluxed at 120° C. for 5 h to obtain a crude product, which was purified to obtain a product as shown in formula IV; (4) Add 0.25 mol of lithium hexafluorophosphate to 0.2 mol of the aqueous solution of the product of formula IV, stir and react at room temperature for 24 hours, extract with ethyl acetate after the reaction is completed, wash with distilled water, dry over anhydrous magnesium sulfate, and evaporate the solvent under reduced pressure to obtain the target product, as shown in formula V; Formula II Formula III Formula IV Formula V.

3. A method for preparing the ionic liquid according to claim 1, characterized in that: The steps include: (1) 0.5 mol of butyric acid and 0.5 mol of ethylene glycol amine are added to a reaction container, stirred and mixed, and 0.01 mol of 10% concentration KOH is added as a catalyst. Under a nitrogen atmosphere, the mixture is stirred and reacted at 110° C. for 4 h to obtain N,N-dihydroxyethyl butylamide, as shown in Formula II; (2) Under nitrogen protection, 0.5 mol of 2-thiobutyl-1,3,4-thiadiazole, 300 mL of anhydrous ethanol, and 0.55 mol of 2-chloroethanol were added to a reaction vessel, heated in a water bath at 61°C, and stirred for 6 hours. After the reaction was completed, the reaction was cooled to room temperature, the insoluble matter was filtered, and the layers were allowed to stand to separate. The lower layer of liquid was separated, and the solvent was removed by distillation under reduced pressure after washing with ether for 3-4 times to obtain 3-hydroxyethyl-2-mercapto-5-methylthiadiazole, as shown in Formula III; (3) Under nitrogen protection, 0.2 mol of the compound of formula II, 0.2 mol of the compound of formula III and 0.25 mol of boric acid were added to a reaction vessel, 300 mL of toluene was added as a water carrier to the mixture, and condensed and refluxed at 130° C. for 5 h to obtain a crude product, which was purified to obtain a product as shown in formula IV; (4) 0.25 mol of lithium trifluoromethanesulfonate is added to 0.2 mol of the aqueous solution of the product of formula IV, and the mixture is stirred at room temperature for 24 hours. After the reaction is completed, the mixture is extracted with ethyl acetate, washed with distilled water, dried over anhydrous magnesium sulfate, and the solvent is evaporated under reduced pressure to obtain the target product, as shown in formula VI; Formula II Formula III Formula IV Formula VI.

4. A method for preparing the ionic liquid according to claim 1, characterized in that: The steps include: (1) 0.5 mol of butyric acid and 0.5 mol of ethylene glycol amine are added to a reaction container, stirred and mixed, and 0.01 mol of 10% concentration KOH is added as a catalyst. Under a nitrogen atmosphere, the mixture is stirred and reacted at 110° C. for 4 h to obtain N,N-dihydroxyethyl butylamide, as shown in Formula II; (2) Under nitrogen protection, 0.5 mol of 2-butyl thioacetate-1,3,4-thiadiazole, 300 mL of anhydrous ethanol, and 0.55 mol of 2-chloroethanol were added to a reaction vessel, heated in a water bath at 60-62° C., and stirred for reaction for 4 hours. After the reaction was completed, the mixture was cooled to room temperature, insoluble matter was filtered, and the mixture was allowed to stand for stratification. The lower layer of liquid was separated, and washed with ether for 4 times. The solvent was then distilled off under reduced pressure to obtain 3-hydroxyethyl-2-mercapto-5-methylthiadiazole, as shown in Formula III; (3) Under nitrogen protection, 0.2 mol of the compound of formula II, 0.2 mol of the compound of formula III and 0.25 mol of boric acid were added to a reaction vessel, 300 mL of toluene was added to the mixture as a water carrier, and condensed and refluxed at 120° C. for 5 h to obtain a crude product, which was purified to obtain a product as shown in formula IV; (4) Add 0.25 mol of lithium bis(trifluoromethanesulfonyl)imide to 0.2 mol of the aqueous solution of the product of formula IV, stir and react at room temperature for 24 hours, extract with ethyl acetate after the reaction is completed, wash with distilled water, dry over anhydrous magnesium sulfate, and evaporate the solvent under reduced pressure to obtain the target product, as shown in formula VII; Formula II Formula III Formula IV Formula VII.

5. A lubricant, characterized in that: The lubricant comprises the ionic liquid according to claim 1.

6. The lubricant according to claim 5, characterized in that: The ionic liquid is added to the lubricant in an amount of 1-15 wt %.

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