Lubricating base oil, preparation method thereof, lubricating oil composition and application

Abstract

The invention belongs to the technical field of lubricating oil, and particularly relates to lubricating base oil, a preparation method thereof, a lubricating oil composition and application. The preparation method comprises the following step: in the presence of an initiator and a solvent, carrying out copolymerization reaction on vinyl laurate and a comonomer containing tetravinyl tetramethyl cyclotetrasiloxane and vinyl polyoxypropylene ether. The lubricating base oil prepared by the preparation method disclosed by the invention not only has demulsibility and lubricating wear resistance, but also realizes good compatibility with the graphene powder.

Description

Technical Field

[0001] The present invention belongs to the technical field of lubricating oils, and particularly relates to a lubricating base oil, a preparation method thereof, a lubricating oil composition and an application. Background Art

[0002] In the modern industrial field, lubricants are key materials for the normal operation of mechanical equipment, and their performance directly affects the efficiency, life and reliability of the equipment. With the continuous progress of industrial technology, the working conditions of mechanical equipment are becoming increasingly complex, and the performance requirements for lubricants are also getting higher and higher. Although traditional lubricating base oils perform well in lubricity and anti-wear properties, their anti-emulsification and stability are often difficult to meet the requirements under extreme working conditions (such as high temperature, high humidity, high load, etc.). In addition, traditional lubricants are prone to performance degradation due to the sedimentation or failure of additives during long-term use, which limits their application in high-performance fields.

[0003] In recent years, the rapid development of nanomaterial technology has provided new possibilities for improving the performance of lubricants. As a new type of two-dimensional nanomaterial, graphene exhibits excellent mechanical properties, thermal conductivity and chemical stability due to its unique structure and high specific surface area, and is considered an ideal additive in the field of lubricants. However, the application of graphene in lubricants faces a key problem: its compatibility with the base oil is poor, and it is prone to agglomeration, resulting in uneven dispersion, which affects the overall performance of the lubricant. Summary of the Invention

[0004] In the first aspect of the present invention, a preparation method of a lubricating base oil is provided, and the preparation method includes:

[0005] In the presence of an initiator and a solvent, vinyl laurate is copolymerized with a comonomer containing tetravinyltetramethylcyclotetrasiloxane and vinyl polyoxypropylene ether.

[0006] The lubricating base oil in existing lubricating oils is the main component of the lubricating oil. In order to lubricate and anti-wear, inorganic powders are generally added to the lubricating oil composition. The most common one is graphene powder at present, which can better increase the lubrication and anti-wear properties of the lubricating oil. However, the dispersibility of graphene powder in the existing lubricating base oil is poor, and precipitation will occur especially at low temperatures. The lubricating base oil in the present invention has excellent high-temperature resistance, and it can better increase the dispersibility of graphene powder in it. It is speculated that because the lubricating base oil contains the structural unit provided by tetravinyltetramethylcyclotetrasiloxane, its siloxane can better interact with graphene powder, and at the same time, the short branched chain of methyl can make graphene powder better dispersed.

[0007] As a preferred technical solution of the present invention, the molar ratio of vinyl laurate to tetravinyltetramethylcyclotetrasiloxane is 1:(0.02 - 0.1), for example, 1:0.02, 1:0.03, 1:0.04, 1:0.05, 1:0.06, 1:0.07, 1:0.08, 1:0.09, 1:0.1, and preferably 1:(0.03 - 0.04).

[0008] In the present invention, it is found that the lubricating base oil prepared by controlling the molar ratio of vinyl laurate to tetravinyltetramethylcyclotetrasiloxane within the above range has better comprehensive properties when used as a lubricating oil, especially lubricating anti-wear performance.

[0009] Allyl epoxy ether vinyl polyoxypropylene ether contains allyl (-CH 2 -CH=CH 2 ) and oxypropylene ether structure. The inventors in the present invention found that the lubricating base oil prepared by adding vinyl polyoxypropylene ether in the comonomer has a demulsification effect. It is speculated that because the oxypropylene ether structure in vinyl polyoxypropylene ether has a certain hydrophobicity, the lubricating oil containing the lubricating base oil has excellent demulsification effect. As a preferred technical solution of the present invention, the average molecular weight of the vinyl polyoxypropylene ether is 1000 - 2000 g / mol, for example, 1000 g / mol, 1200 g / mol, 1500 g / mol, 1800 g / mol or 2000 g / mol, and preferably 1200 - 1800 g / mol.

[0010] In the present invention, it is found that the lubricating base oil prepared by using vinyl polyoxypropylene ether with a molecular weight within the above range can make the lubricating oil composition have better lubricating anti-wear performance and anti-emulsification effect. At the same time, the lubricating base oil prepared by using vinyl polyoxypropylene ether with too large a molecular weight is not conducive to the dispersion of graphene powder.

[0011] As a preferred technical solution of the present invention, the molar ratio of vinyl laurate to vinyl polyoxypropylene ether is 1:(0.1 - 1), for example, 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.7, 1:0.8, 1:0.9, 1:1, and preferably 1:(0.2 - 0.4).

[0012] In the present invention, the lubricating base oil prepared by controlling the amounts of vinyl laurate and vinyl polyoxypropylene ether within the above range has better comprehensive properties.

[0013] As a preferred technical solution of the present invention, the comonomer further contains 1-vinyl-3-hexylimidazolium salt.

[0014] The inventors of the present invention further found in their research that 1-vinyl-3-hexylimidazolium salt can enable the lubricating base oil to better synergistically interact with graphene powder to increase the lubricating and anti-wear properties of the lubricating oil composition during the preparation of the lubricating base oil. It is speculated that this is because the cations and anions provided by the structural units in the lubricating base oil it provides can be adsorbed on the metal surface through electrostatic interaction to form a stable lubricating film, reducing the direct contact between the friction pairs.

[0015] As a more preferred technical solution of the present invention, the 1-vinyl-3-hexylimidazolium salt is selected from at least one of 1-vinyl-3-hexylimidazolium bromide, 1-vinyl-3-hexylimidazolium tetrafluoroborate, 1-vinyl-3-hexylimidazolium hexafluorophosphate, and 1-vinyl-3-hexylimidazolium bis(trifluoromethanesulfonyl)imide salt, and is preferably 1-vinyl-3-hexylimidazolium hexafluorophosphate.

[0016] In the present invention, it is found through research that when the anion of the 1-vinyl-3-hexylimidazolium salt is hexafluorophosphate ion, the prepared lubricating base oil has better lubricating and anti-wear properties when used in the lubricating oil composition. It is speculated that this is because hexafluorophosphate can react with the metal on the mechanical surface to generate a phosphate protective film during use.

[0017] As a more preferred technical solution of the present invention, the molar ratio of the vinyl laurate to the 1-vinyl-3-hexylimidazolium salt is 1:(0.05 - 0.2), such as 1:0.05, 1:0.07, 1:0.08, 1:0.09, 1:1, 1:0.13, 1:0.15, 1:0.18, 1:0.2, and is preferably 1:(0.12 - 0.15).

[0018] In the present invention, the lubricating base oil prepared by controlling the amounts of the vinyl laurate and the 1-vinyl-3-hexylimidazolium salt within the above ranges has better comprehensive properties.

[0019] In the present invention, the type of the initiator can be any initiator capable of initiating copolymerization reaction in the art. As a preferred technical solution of the present invention, the initiator is selected from peroxide initiators and / or azo initiators.

[0020] Peroxide initiators that can be listed in the present invention include benzoyl peroxide, dicumyl peroxide, dilauroyl peroxide, di-tert-butyl peroxide, diisopropyl peroxydicarbonate, tert-butyl peroxyneopentanoate, hydrogen peroxide, ammonium persulfate, methyl ethyl ketone peroxide, acetylacetone peroxide, etc.

[0021] The azo initiators that can be listed in the present invention include azobisisobutyronitrile, azobisisoheptonitrile, dimethyl azobisisobutyrate, dicyclohexylmethyl azoformamide, azobis(isobutyramidine) hydrochloride, dimethyl azobisisobutyrate, diethyl azobisisobutyrate, dibutyl azobisisobutyrate, diisopropyl azobisisobutyrate, diethyl azobisisobutyrate, etc.

[0022] The initiator in the present invention is preferably an azo initiator. Specifically, azobisisobutyronitrile is used as an example to illustrate the advantages of the present invention, but it does not represent a limitation to the present invention.

[0023] As a preferred technical solution of the present invention, based on the total mass of vinyl laurate and the comonomer, the mass of the initiator is 0.05 - 0.5 wt%, preferably 0.1 - 0.2 wt%; that is, the dosage of the initiator is 0.05 - 0.5 wt% of the total mass of vinyl laurate and the comonomer, preferably 0.1 - 0.2 wt%.

[0024] The solvent in the present invention can be any solvent in the art that does not participate in the copolymerization reaction and can promote heat transfer and avoid local overheating during the copolymerization reaction. As a preferred technical solution of the present invention, the solvent is selected from at least one of benzene, xylene, and tetrahydrofuran, preferably toluene.

[0025] As a preferred technical solution of the present invention, based on the total mass of vinyl laurate and the comonomer, the mass of the solvent is 1.2 - 5 times, preferably 2 - 4 times; that is, the dosage of the solvent is 1.2 - 5 times the total mass of vinyl laurate and the comonomer, preferably 2 - 4 times.

[0026] To avoid the influence of oxygen and water vapor in the air on the copolymerization reaction, as a preferred technical solution of the present invention, the conditions for the copolymerization reaction include: carried out in a nitrogen atmosphere.

[0027] As a preferred technical solution of the present invention, the conditions for the copolymerization reaction include: the temperature is 60 - 80 °C.

[0028] As a preferred technical solution of the present invention, the conditions for the copolymerization reaction include: the time is 1 - 5 hours, preferably 2 - 2.5 hours.

[0029] In the present invention, it is found that the viscosity of the lubricating base oil prepared with too long copolymerization time is too high and it cannot be used well as a lubricating base oil.

[0030] The lubricating base oil obtained after the copolymerization reaction of the present invention still contains a solvent. In order to obtain the final lubricating base oil, as a preferred technical solution of the present invention, the copolymerization reaction further includes a post-treatment step of removing the solvent. Preferably, the post-treatment step is distillation, and this distillation method is a conventional method in the art, and the present invention will not elaborate on it here.

[0031] The second aspect of the present invention provides a lubricating base oil, which is prepared by the preparation method of the lubricating base oil described in the first aspect of the present invention.

[0032] The lubricating base oil prepared by the preparation method of the present invention not only has excellent lubricating and wear resistance, but also has excellent demulsibility.

[0033] The third aspect of the present invention provides a lubricating oil composition, which contains graphene powder and the lubricating base oil described in the second aspect of the present invention.

[0034] In the present invention, the lubricating oil composition containing the lubricating base oil of the present invention not only has excellent lubricating and wear resistance, but also has excellent dispersion stability for graphene powder at low temperature.

[0035] The graphene powder in the present invention is a conventional graphene powder in the art and can be obtained commercially. For example, the KNG-G2 graphene powder purchased from Xiamen Kaina Graphene Technology Co., Ltd.

[0036] As a preferred technical solution of the present invention, the mass ratio of the graphene powder to the lubricating base oil is (0.5 - 2):100, preferably (1 - 1.2):100.

[0037] The fourth aspect of the present invention provides the application of the lubricating oil composition described in the third aspect of the present invention in machinery.

[0038] The lubricating oil composition in the present invention can play a role in reducing friction and wear when used in machinery, such as moving parts of engines, gearboxes, bearings, etc.

[0039] When the lubricating oil composition in the present invention is used, the various components in the composition can be mixed and then used. The mixing method is preferably shearing at a shearing speed of 20000 - 40000 r / min for 10 - 20 min, then sanding at a sanding line speed of 10 - 20 m / s and with 1 - 2 mm ceramic beads for 1 - 1.5 h, and finally ultrasonicating at an ultrasonic power of 1000 - 2000 W for 20 - 30 min to obtain the lubricating oil.

[0040] Compared with the prior art, the present invention has at least the following beneficial effects:

[0041] 1. The lubricating base oil in the present invention itself has excellent anti-emulsification and lubricating anti-wear properties, can maintain stable lubricating performance under complex working conditions, effectively reduce friction and wear, and extend the service life of mechanical equipment.

[0042] 2. As a new type of nanomaterial, graphene powder has an extremely high specific surface area, excellent mechanical strength and thermal conductivity, and can significantly improve the comprehensive performance of lubricants. In the present invention, there is good compatibility between graphene powder and lubricating base oil, which enables graphene to be evenly dispersed in the base oil, avoiding performance degradation caused by agglomeration, and the combination of the two further enhances the anti-wear and friction reduction effects of the lubricant. Specific Embodiments

[0043] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0044] Example 1

[0045] Preparation of lubricating base oil:

[0046] Toluene and azobisisobutyronitrile were added to the reaction kettle, and then vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether (average molecular weight of 1800 g / mol) and 1-vinyl-3-hexylimidazolium hexafluorophosphate with a molar ratio of 1:0.03:0.4:0.12 were added. After purging the air in the reaction kettle with nitrogen for 30 minutes, the reaction system was heated to 60 °C and reacted for 2.5 hours and then cooled to room temperature. The reaction solution was distilled to remove toluene to obtain the lubricating base oil; wherein, the mass of toluene was 2.3 times the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether and 1-vinyl-3-hexylimidazolium hexafluorophosphate, and the mass of azobisisobutyronitrile was 0.12 wt% of the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether and 1-vinyl-3-hexylimidazolium hexafluorophosphate.

[0047] Example 2

[0048] Preparation of lubricating base oil:

[0049] Toluene and azobisisobutyronitrile were added to a reaction kettle, and then vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether (average molecular weight 1200 g / mol), and 1-vinyl-3-hexylimidazolium hexafluorophosphate with a molar ratio of 1:0.04:0.2:0.15 were added. After purging the air in the reaction kettle with nitrogen for 30 min, the reaction system was heated to 80 °C and reacted for 2 hours, and then cooled to room temperature. The reaction solution was distilled to remove toluene to obtain a lubricating base oil; wherein, the mass of toluene was 2.5 times the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether, and 1-vinyl-3-hexylimidazolium hexafluorophosphate, and the mass of azobisisobutyronitrile was 0.15 wt% of the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether, and 1-vinyl-3-hexylimidazolium hexafluorophosphate.

[0050] Example 3

[0051] Preparation of lubricating base oil:

[0052] Toluene and azobisisobutyronitrile were added to a reaction kettle, and then vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether (average molecular weight 1200 g / mol), and 1-vinyl-3-hexylimidazolium hexafluorophosphate with a molar ratio of 1:0.035:0.3:0.15 were added. After purging the air in the reaction kettle with nitrogen for 30 min, the reaction system was heated to 70 °C and reacted for 2.5 hours, and then cooled to room temperature. The reaction solution was distilled to remove toluene to obtain a lubricating base oil; wherein, the mass of toluene was 2.5 times the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether, and 1-vinyl-3-hexylimidazolium hexafluorophosphate, and the mass of azobisisobutyronitrile was 0.15 wt% of the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether, and 1-vinyl-3-hexylimidazolium hexafluorophosphate.

[0053] Example 4

[0054] Preparation of lubricating base oil:

[0055] Toluene and azobisisobutyronitrile were added into a reaction kettle, and then vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether (average molecular weight: 3200 g / mol), and 1-vinyl-3-hexylimidazolium hexafluorophosphate with a molar ratio of 1:0.035:0.3:0.15 were added. After purging the air in the reaction kettle with nitrogen for 30 min, the reaction system was heated to 70 °C and reacted for 2.5 h, and then cooled to room temperature. The reaction solution was distilled to remove toluene to obtain a lubricating base oil. Among them, the mass of toluene was 2.5 times the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether, and 1-vinyl-3-hexylimidazolium hexafluorophosphate, and the mass of azobisisobutyronitrile was 0.15 wt% of the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether, and 1-vinyl-3-hexylimidazolium hexafluorophosphate.

[0056] Example 5

[0057] Preparation of lubricating base oil:

[0058] Toluene and azobisisobutyronitrile were added into a reaction kettle, and then vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether (average molecular weight: 500 g / mol), and 1-vinyl-3-hexylimidazolium hexafluorophosphate with a molar ratio of 1:0.035:0.3:0.15 were added. After purging the air in the reaction kettle with nitrogen for 30 min, the reaction system was heated to 70 °C and reacted for 2.5 h, and then cooled to room temperature. The reaction solution was distilled to remove toluene to obtain a lubricating base oil. Among them, the mass of toluene was 2.5 times the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether, and 1-vinyl-3-hexylimidazolium hexafluorophosphate, and the mass of azobisisobutyronitrile was 0.15 wt% of the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether, and 1-vinyl-3-hexylimidazolium hexafluorophosphate.

[0059] Example 6

[0060] Preparation of lubricating base oil:

[0061] Toluene and azobisisobutyronitrile were added to a reaction kettle, and then vinyl laurate, tetravinyltetramethylcyclotetrasiloxane and vinyl polyoxypropylene ether (average molecular weight: 1200 g / mol) with a molar ratio of 1:0.035:0.3 were added. After purging the air in the reaction kettle with nitrogen for 30 min, the reaction system was heated to 70 °C and reacted for 2.5 h, and then cooled to room temperature. The reaction solution was distilled to remove toluene to obtain a lubricating base oil; wherein, the mass of toluene was 2.5 times the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane and vinyl polyoxypropylene ether, and the mass of azobisisobutyronitrile was 0.15 wt% of the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane and vinyl polyoxypropylene ether.

[0062] Example 7

[0063] Preparation of lubricating base oil:

[0064] Toluene and azobisisobutyronitrile were added to a reaction kettle, and then vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether (average molecular weight: 1200 g / mol) and 1-vinyl-3-hexylimidazolium bromide with a molar ratio of 1:0.035:0.3:0.15 were added. After purging the air in the reaction kettle with nitrogen for 30 min, the reaction system was heated to 70 °C and reacted for 2.5 h, and then cooled to room temperature. The reaction solution was distilled to remove toluene to obtain a lubricating base oil; wherein, the mass of toluene was 2.5 times the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether and 1-vinyl-3-hexylimidazolium bromide, and the mass of azobisisobutyronitrile was 0.15 wt% of the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane, vinyl polyoxypropylene ether and 1-vinyl-3-hexylimidazolium bromide.

[0065] Comparative Example 1

[0066] Preparation of lubricating base oil:

[0067] Toluene and azobisisobutyronitrile were added to a reaction kettle, and then vinyl laurate, tetravinyltetramethylcyclotetrasiloxane and 1-vinyl-3-hexylimidazolium hexafluorophosphate with a molar ratio of 1:0.035:0.3:0.15 were added. After purging the air in the reaction kettle with nitrogen for 30 min, the reaction system was heated to 70 °C and reacted for 2.5 h, and then cooled to room temperature. The reaction solution was distilled to remove toluene to obtain a lubricating base oil; wherein, the mass of toluene was 2.5 times the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane and 1-vinyl-3-hexylimidazolium hexafluorophosphate, and the mass of azobisisobutyronitrile was 0.15 wt% of the total mass of vinyl laurate, tetravinyltetramethylcyclotetrasiloxane and 1-vinyl-3-hexylimidazolium hexafluorophosphate.

[0068] Comparative Example 2

[0069] Preparation of lubricating base oil:

[0070] Toluene and azobisisobutyronitrile were added to a reaction kettle, and then vinyl laurate, vinyl polyoxypropylene ether (average molecular weight 1200 g / mol) and 1-vinyl-3-hexylimidazolium hexafluorophosphate with a molar ratio of 1:0.035:0.3:0.15 were added. After purging the air in the reaction kettle with nitrogen for 30 min, the reaction system was heated to 70 °C and reacted for 2.5 h and then cooled to room temperature. The reaction solution was distilled to remove toluene to obtain the lubricating base oil; wherein, the mass of toluene was 2.5 times the total mass of vinyl laurate, vinyl polyoxypropylene ether and 1-vinyl-3-hexylimidazolium hexafluorophosphate, and the mass of azobisisobutyronitrile was 0.15 wt% of the total mass of vinyl laurate, vinyl polyoxypropylene ether and 1-vinyl-3-hexylimidazolium hexafluorophosphate.

[0071] Application Examples 1-7 and Application Comparative Examples 1-2

[0072] The lubricating base oils in Examples 1-7 and Comparative Examples 1-2 were respectively used to prepare lubricating oils. The specific preparation method was as follows:

[0073] Graphene powder (KNG-G2 graphene powder purchased from Xiamen Kaina Graphene Technology Co., Ltd.) and lubricating base oil with a mass ratio of 1:100 were sheared at a shear rate of 30000 r / min for 15 min, then sanded for 1 h under the conditions of a sanding linear velocity of 12 m / s and 1.5 mm ceramic beads, and finally ultrasonically treated for 30 min under the condition of an ultrasonic power of 1200 W to obtain the lubricating oil.

[0074] 1. Demulsibility: According to the standard method of GB / T 7305, the lubricating oils in the examples and comparative examples were respectively used as test samples for the demulsibility test: 40 mL of each of the test sample and distilled water were respectively put into a graduated cylinder, and stirred at a speed of 1500 r / min for 5 min at a test temperature of 54 °C. Record the separation time of the lubricating oil and water (40 oil - 40 water - 0 emulsion layer) mL. The shorter the separation time, the better the demulsibility of the oil product.

[0075] 2. Whether there is precipitation: The lubricating oils in the examples and comparative examples were respectively placed at -5 ± 1 °C for 7 days and observed whether there was precipitation.

[0076] 3. Friction coefficient test: The test conditions were: testing was carried out at a temperature of 25 ± 5 °C, a load of 196 N, and a spindle speed of 1200 r / min.

[0077] The results of the anti-emulsification property of the lubricating oil, whether there is precipitation, and the friction coefficient are shown in Table 1.

[0078] Table 1 Results of the anti-emulsification property of the lubricating oil, whether there is precipitation, and the friction coefficient

[0079]

[0080]

[0081] From the above performance test results, it can be seen that the lubricating base oil prepared in the present invention not only has anti-emulsification property and lubricating and anti-wear property, but also achieves good compatibility with graphene powder.

[0082] The above is the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing a lubricating base oil, characterized in that: The preparation method comprises: in the presence of an initiator and a solvent, vinyl laurate and a copolymer monomer containing tetravinyltetramethylcyclotetrasiloxane and vinyl polyoxypropylene ether are copolymerized.

2. The preparation method according to claim 1, characterized in that: The molar ratio of the vinyl laurate to tetravinyltetramethylcyclotetrasiloxane is 1:(0.02-0.1).

3. The preparation method according to claim 1, characterized in that: The average molecular weight of the vinyl polyoxypropylene ether is 1000-2000 g / mol; the molar ratio of the vinyl laurate to the vinyl polyoxypropylene ether is 1:(0.1-1).

4. The preparation method according to claim 1, characterized in that: The comonomer also contains 1-vinyl-3-hexyl imidazole salt.

5. The preparation method according to claim 1, characterized in that: The initiator is selected from peroxide initiators and / or azo initiators; based on the total mass of vinyl laurate and the comonomer, the mass of the initiator is 0.05-0.5wt%.

6. The preparation method according to claim 1, characterized in that: The solvent is selected from at least one of benzene, xylene and tetrahydrofuran; based on the total mass of vinyl laurate and the comonomer, the mass of the solvent is 1.2-5 times.

7. The preparation method according to claim 1, characterized in that: The copolymerization reaction conditions include: being carried out in a nitrogen atmosphere; the temperature is 60-80° C.; and the time is 1-5 hours.

8. A lubricating base oil, characterized in that: The lubricating base oil is prepared by the preparation method described in any one of claims 1 to 7.

9. A lubricating oil composition, characterized in that: The lubricating oil composition contains graphene powder and the lubricating base oil according to claim 8.

10. Use of the lubricating oil composition according to claim 9 in machinery.

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