Lubricating grease composition with excellent heat-resistant stability as well as preparation method and application thereof

Abstract

The invention relates to the field of lubricating grease, in particular to a lubricating grease composition with excellent heat-resistant stability as well as a preparation method and application thereof, which are used for solving the problems that although an existing lubricating grease product is good in performance in daily application, the lubricating effect is still not ideal under high-temperature and high-speed operation; the reliability and the service life of the equipment are influenced; the lubricating grease composition comprises the following components: base oil, an organic phosphorus-nitrogen polyfluorine modifier, a thickening agent, an antioxidant, an antirust agent and nano tungsten disulfide, according to the preparation method, the lubricating property and the heat resistance of the lubricating grease composition can be remarkably improved by adding the organic phosphorus-nitrogen polyfluorine modifier into the lubricating grease composition, so that the lubricating grease composition keeps efficient lubricating property under a high-temperature condition; the lubricating grease composition can still continuously provide effective lubricating protection in high-temperature and severe environments, and the super-long service life under extreme working conditions of high-speed bearings, humanoid robot joints and the like is ensured.

Description

Technical Field

[0001] This invention relates to the field of lubricating greases, and more specifically to a lubricating grease composition with excellent heat resistance and stability, its preparation method, and its application. Background Technology

[0002] In industrial manufacturing, lubricating grease is a key material for reducing friction, wear, and heat accumulation in mechanical parts. It improves equipment operating efficiency and extends service life. While traditional lubricating greases perform well in everyday applications, their heat resistance and stability often fail to meet the demands of high-temperature or high-speed operation scenarios. This is especially true for high-speed bearings, where the high temperatures generated by their operation place even higher demands on the heat resistance of the grease. Existing lubricating greases exhibit poor thermal stability under high-temperature conditions, making them prone to deterioration or decomposition. For humanoid robots, which need to withstand complex and varied motion and environmental conditions, lubricating greases must not only possess excellent lubrication properties but also remain stable under various harsh conditions to ensure the flexible operation and reliable performance of the robot's joints.

[0003] In view of the above problems, developing a lubricating grease composition with excellent heat resistance and stability, as well as its preparation method and application, is of great practical significance. Summary of the Invention

[0004] In order to overcome the above-mentioned technical problems, the present invention aims to provide a grease composition with excellent heat resistance and stability, its preparation method and application, which solves the problem that although existing grease products perform well in daily applications, their lubrication effect is still not ideal under high temperature and high speed operation, thus affecting the reliability and life of equipment.

[0005] The objective of this invention can be achieved through the following technical solutions: In a first aspect, this application provides a grease composition with excellent heat resistance and stability, comprising the following components in parts by weight: The composition includes 78-86 parts base oil, 1-9 parts organophosphorus nitrogen polyfluorine modifier, 12-16 parts thickener, 0.8-1.6 parts antioxidant, 0.7-1.5 parts rust inhibitor, and 0.6-1.2 parts nano tungsten disulfide. The organophosphorus nitrogen polyfluorine modifier is prepared by the following steps: Step a1: 2,5-Dibromobenzene-1,4-dicarboxaldehyde, 4-trifluoromethylphenylboronic acid, tetra(triphenylphosphine)palladium, sodium carbonate, toluene, and deionized water were added to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Nitrogen gas was introduced for protection, and the mixture was stirred for 10-20 min at a temperature of 20-25℃ and a stirring rate of 200-300 r / min. Then, the temperature was raised to 80-90℃ and the stirring was continued for 20-30 h. After the reaction was completed, the reaction product was cooled to room temperature and then extracted with ethyl acetate 2-3 times. The extracts were combined and washed 2-3 times with distilled water and saturated brine, respectively. The mixture was then dried with anhydrous magnesium sulfate and vacuum filtered. The solvent was removed by rotary evaporation of the filtrate to obtain the dialdehyde polyfluoride compound. Step a2: Add the dialdehyde polyfluorinated compound, 4-trifluoromethylaniline and ethanol to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir the reaction at 0-5℃ and 200-300 r / min for 30-40 min. Then raise the temperature to 70-80℃ and continue stirring for 8-10 h. After the reaction is completed, cool the reaction product to 0-5℃ and then filter under vacuum. Wash the filter cake 2-3 times with ice-cold ethanol and then place it in a vacuum drying oven and dry it at 50-60℃ for 3-6 h to obtain the Schiff base polyfluorinated compound. Step a3: Add Schiff base polyfluoride compound, DOPO and ethanol to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection. Stir the reaction at 20-25℃ and 200-300 r / min for 10-20 min. Then raise the temperature to 50-60℃ and continue stirring for 2-3 h. Then raise the temperature to 70-80℃ and continue stirring for 8-10 h. After the reaction is completed, cool the reaction product to 0-5℃ and then filter under vacuum. Recrystallize the filter cake with N,N-dimethylformamide to obtain organophosphorus nitrogen polyfluoride modifier.

[0006] In a preferred embodiment of the present invention, the ratio of 2,5-dibromobenzene-1,4-dicarboxaldehyde, 4-trifluoromethylphenylboronic acid, tetra(triphenylphosphine)palladium, sodium carbonate, toluene and deionized water in step a1 is 10 mmol: 20 mmol: 0.2-0.3 g: 25-30 mmol: 40-50 mL: 10-15 mL.

[0007] In a preferred embodiment of the present invention, the ratio of the dialdehyde polyfluorinated compound, 4-trifluoromethylaniline and ethanol in step a2 is 10 mmol: 20 mmol: 60-70 mL.

[0008] In a preferred embodiment of the present invention, the ratio of Schiff base polyfluoride compound, DOPO and ethanol in step a3 is 10 mmol: 20 mmol: 90-100 mL.

[0009] Secondly, this application provides a method for preparing a lubricating grease composition with excellent heat resistance and stability, comprising the following steps: Step 1: Weigh out 78-86 parts of base oil, 1-9 parts of organophosphorus nitrogen polyfluorine modifier, 12-16 parts of thickener, 0.8-1.6 parts of antioxidant, 0.7-1.5 parts of rust inhibitor, and 0.6-1.2 parts of nano tungsten disulfide according to the following weight proportions, and set aside for later use; Step 2: Add 1 / 2 weight of base oil and thickener to the reaction vessel and stir and mix for 1-3 hours at a temperature of 100-120℃ and a stirring rate of 500-600 r / min. Then, raise the temperature to 150-160℃ and continue stirring and mixing for 30-50 minutes. After that, raise the temperature to 180-200℃ and continue stirring and mixing for 10-20 minutes. Then, lower the temperature to 100-120℃ and add the remaining base oil, organophosphorus nitrogen polyfluorine modifier, antioxidant, rust inhibitor, and nano tungsten disulfide. Continue stirring and mixing for 1-2 hours. After that, cool to room temperature to obtain a grease composition with excellent heat resistance and stability.

[0010] In a preferred embodiment of the present invention, the base oil is poly-α-olefin PAO100.

[0011] In a preferred embodiment of the present invention, the thickener is ASE-60 polyurea thickener.

[0012] In a preferred embodiment of the present invention, the antioxidant is a mixture of antioxidant and anti-aging agent T-531 in equal mass.

[0013] In a preferred embodiment of the present invention, the rust inhibitor is T706 rust inhibitor.

[0014] In a preferred embodiment of the present invention, the average particle size of the nano-tungsten disulfide is 100 nm.

[0015] Thirdly, this application provides a method for preparing a grease composition with excellent heat resistance and stability, and the application of the prepared grease composition with excellent heat resistance and stability in grease for humanoid robots and grease for high-speed bearings.

[0016] The beneficial effects of this invention are: This invention discloses a grease composition with excellent heat resistance and stability, its preparation method, and its application. The method involves mixing half the weight of base oil and a thickener, then adding the remaining base oil, an organophosphorus-nitrogen polyfluorine modifier, an antioxidant, a rust inhibitor, and nano-tungsten disulfide, continuing the mixing process, and then cooling to room temperature to obtain the grease composition with excellent heat resistance and stability. This preparation method significantly improves the lubrication and heat resistance of the grease composition by adding an organophosphorus-nitrogen polyfluorine modifier, enabling it to maintain high-efficiency lubrication performance under high-temperature conditions. This ensures that the grease composition can continuously provide effective lubrication protection in high-temperature and harsh environments, guaranteeing an ultra-long service life under extreme conditions such as high-speed bearings and humanoid robot joints.

[0017] In the preparation of a grease composition with excellent heat resistance and stability, an organophosphorus nitrogen polyfluorine modifier was first prepared. This involved reacting 2,5-dibromobenzene-1,4-dicarboxaldehyde with 4-trifluoromethylphenylboronic acid, where the bromine atom on 2,5-dibromobenzene-1,4-dicarboxaldehyde reacts with the boric acid group on 4-trifluoromethylphenylboronic acid to form a dialdehyde-based polyfluorine compound containing an aldehyde group and multiple fluorine atoms. Then, the dialdehyde-based polyfluorine compound reacts with 4-trifluoromethylaniline, where the aldehyde group on the dialdehyde-based polyfluorine compound reacts with the amino group on 4-trifluoromethylaniline to form a Schiff base structure, simultaneously introducing a large number of fluorine atoms to obtain a Schiff base polyfluorine compound. Finally, the Schiff base polyfluorine compound reacts with DOPO, where the Schiff base structure on the Schiff base polyfluorine compound undergoes an addition reaction with the pH group on DOPO. The reaction introduces benzene rings and organophosphorus compounds, yielding an organophosphorus nitrogen-fluorinated modifier. This modifier's molecular structure contains numerous benzene rings, endowing it with excellent thermal stability. Furthermore, its molecular structure contains a large number of CF bonds, which have extremely high bond energies and are very stable, making them difficult to break under high temperatures or oxidizing environments. This further enhances the overall molecular thermal decomposition temperature and chemical stability. Moreover, due to the extremely high electronegativity of fluorine atoms, it can significantly reduce surface energy, forming a dense, low-shear-strength fluorinated protective film that effectively isolates direct metal contact, significantly reducing the coefficient of friction. The presence of N and P atoms in the molecular structure not only further enhances thermal stability but also allows for strong chemical adsorption onto metal surfaces, forming a robust adsorption film that further improves lubrication performance. Therefore, adding the organophosphorus nitrogen-fluorinated modifier to a grease composition can significantly improve its lubrication and heat resistance. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1:

[0020] This embodiment describes a method for preparing a lubricating grease composition with excellent heat resistance and stability, comprising the following steps: Step S1: 10 mmol of 2,5-dibromobenzene-1,4-dicarboxaldehyde, 20 mmol of 4-trifluoromethylphenylboronic acid, 0.2 g of tetra(triphenylphosphine)palladium, 25 mmol of sodium carbonate, 40 mL of toluene, and 10 mL of deionized water were added to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Nitrogen gas was introduced for protection, and the mixture was stirred at 20 °C and a stirring rate of 200 r / min for 10 min. Then, the temperature was raised to 80 °C and the mixture was stirred for 20 h. After the reaction was completed, the reaction product was cooled to room temperature and then extracted twice with ethyl acetate. The extracts were combined and washed twice with distilled water and saturated brine, respectively. The mixture was then dried with anhydrous magnesium sulfate and then filtered under vacuum. The solvent was removed by rotary evaporation of the filtrate to obtain dialdehyde polyfluoride. Step S2: 10 mmol of dialdehyde polyfluoride, 20 mmol of 4-trifluoromethylaniline and 60 mL of ethanol were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 0 °C and 200 r / min for 30 min. Then the temperature was raised to 70 °C and the mixture was stirred for 8 h. After the reaction was completed, the reaction product was cooled to 0 °C and then vacuum filtered. The filter cake was washed twice with ice-cold ethanol and then placed in a vacuum drying oven and dried at 50 °C for 3 h to obtain Schiff base polyfluoride. Step S3: Add 10 mmol of Schiff base polyfluoride compound, 20 mmol of DOPO and 90 mL of ethanol to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir at 20 °C and 200 r / min for 10 min. Then raise the temperature to 50 °C and continue stirring for 2 h. Then raise the temperature to 70 °C and continue stirring for 8 h. After the reaction is completed, cool the reaction product to 0 °C and then filter under vacuum. Recrystallize the filter cake with N,N-dimethylformamide to obtain organophosphorus nitrogen polyfluoride modifier. Step S4: Weigh out 78 parts by weight of base oil, 1 part by weight of organophosphorus nitrogen polyfluorine modifier, 12 parts by weight of thickener, 0.8 parts by weight of antioxidant, 0.7 parts by weight of rust inhibitor, and 0.6 parts by weight of nano-tungsten disulfide, and set aside. The base oil is polyalphaolefin PAO100; the thickener is ASE-60 polyurea thickener; the antioxidant is a mixture of antioxidant and anti-aging agent T-531 in equal mass; the rust inhibitor is T706 rust inhibitor; and the average particle size of the nano-tungsten disulfide is 100 nm. Step S5: Add 1 / 2 weight of base oil and thickener to the reactor and stir and mix for 1 hour at 100°C and 500 r / min. Then, heat to 150°C and continue stirring and mixing for 30 minutes. Then, heat to 180°C and continue stirring and mixing for 10 minutes. Then, cool to 100°C and add the remaining base oil, organophosphorus nitrogen polyfluorine modifier, antioxidant, rust inhibitor and nano tungsten disulfide and continue stirring and mixing for 1 hour. Then, cool to room temperature to obtain a grease composition with excellent heat resistance and stability.

[0021] Example 2:

[0022] This embodiment describes a method for preparing a lubricating grease composition with excellent heat resistance and stability, comprising the following steps: Step S1: 10 mmol of 2,5-dibromobenzene-1,4-dicarboxaldehyde, 20 mmol of 4-trifluoromethylphenylboronic acid, 0.25 g of tetra(triphenylphosphine)palladium, 28 mmol of sodium carbonate, 45 mL of toluene, and 12 mL of deionized water were added to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Nitrogen gas was introduced for protection, and the mixture was stirred at 22 °C and 250 r / min for 15 min. The mixture was then heated to 85 °C and stirred for 25 h. After the reaction was completed, the product was cooled to room temperature and extracted twice with ethyl acetate. The extracts were combined and washed twice with distilled water and saturated brine, respectively. The mixture was then dried with anhydrous magnesium sulfate and vacuum filtered. The solvent was removed by rotary evaporation of the filtrate to obtain the dialdehyde polyfluoride compound. Step S2: 10 mmol of dialdehyde polyfluoride, 20 mmol of 4-trifluoromethylaniline and 65 mL of ethanol were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 3 °C and 250 r / min for 35 min. Then the temperature was raised to 75 °C and the mixture was stirred for 9 h. After the reaction was completed, the reaction product was cooled to 3 °C and then vacuum filtered. The filter cake was washed twice with ice-cold ethanol and then placed in a vacuum drying oven and dried at 55 °C for 4.5 h to obtain Schiff base polyfluoride. Step S3: Add 10 mmol of Schiff base polyfluoride compound, 20 mmol of DOPO and 95 mL of ethanol to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir at 22 °C and 250 r / min for 15 min. Then raise the temperature to 55 °C and continue stirring for 2.5 h. Then raise the temperature to 75 °C and continue stirring for 9 h. After the reaction is completed, cool the reaction product to 3 °C and then filter under vacuum. Recrystallize the filter cake with N,N-dimethylformamide to obtain organophosphorus nitrogen polyfluoride modifier. Step S4: Weigh out 82 parts by weight of base oil, 5 parts by weight of organophosphorus nitrogen polyfluorine modifier, 14 parts by weight of thickener, 1.2 parts by weight of antioxidant, 1.1 parts by weight of rust inhibitor, and 0.9 parts by weight of nano-tungsten disulfide, and set aside. The base oil is polyalphaolefin PAO100; the thickener is ASE-60 polyurea thickener; the antioxidant is a mixture of antioxidant and anti-aging agent T-531 in equal mass; the rust inhibitor is T706 rust inhibitor; and the average particle size of the nano-tungsten disulfide is 100 nm. Step S5: Add 1 / 2 weight of base oil and thickener to the reactor and stir and mix for 2 hours at 110°C and 550 r / min. Then, heat to 155°C and continue stirring and mixing for 40 minutes. Then, heat to 190°C and continue stirring and mixing for 15 minutes. Then, cool to 110°C and add the remaining base oil, organophosphorus nitrogen polyfluorine modifier, antioxidant, rust inhibitor and nano tungsten disulfide. Continue stirring and mixing for 1.5 hours. Then, cool to room temperature to obtain a grease composition with excellent heat resistance and stability.

[0023] Example 3:

[0024] This embodiment describes a method for preparing a lubricating grease composition with excellent heat resistance and stability, comprising the following steps: Step S1: 10 mmol of 2,5-dibromobenzene-1,4-dicarboxaldehyde, 20 mmol of 4-trifluoromethylphenylboronic acid, 0.3 g of tetra(triphenylphosphine)palladium, 30 mmol of sodium carbonate, 50 mL of toluene, and 15 mL of deionized water were added to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Nitrogen gas was introduced for protection, and the mixture was stirred at 25 °C and a stirring rate of 300 r / min for 20 min. Then, the temperature was raised to 90 °C and the mixture was stirred for another 30 h. After the reaction was completed, the reaction product was cooled to room temperature and then extracted three times with ethyl acetate. The extracts were combined and washed three times with distilled water and saturated brine, respectively. The mixture was then dried with anhydrous magnesium sulfate and then filtered under vacuum. The solvent was removed by rotary evaporation of the filtrate to obtain the dialdehyde polyfluoride compound. Step S2: 10 mmol of dialdehyde polyfluoride, 20 mmol of 4-trifluoromethylaniline and 70 mL of ethanol were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 5 °C and 300 r / min for 40 min. Then the temperature was raised to 80 °C and the mixture was stirred for 10 h. After the reaction was completed, the reaction product was cooled to 5 °C and then vacuum filtered. The filter cake was washed three times with ice-cold ethanol and then placed in a vacuum drying oven and dried at 60 °C for 6 h to obtain Schiff base polyfluoride. Step S3: Add 10 mmol of Schiff base polyfluoride compound, 20 mmol of DOPO and 100 mL of ethanol to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir at 25 °C and 300 r / min for 20 min. Then raise the temperature to 60 °C and continue stirring for 3 h. Then raise the temperature to 80 °C and continue stirring for 10 h. After the reaction is completed, cool the reaction product to 5 °C and then filter under vacuum. Recrystallize the filter cake with N,N-dimethylformamide to obtain organophosphorus nitrogen polyfluoride modifier. Step S4: Weigh out 86 parts by weight of base oil, 9 parts by weight of organophosphorus nitrogen polyfluorine modifier, 16 parts by weight of thickener, 1.6 parts by weight of antioxidant, 1.5 parts by weight of rust inhibitor, and 1.2 parts by weight of nano-tungsten disulfide, and set aside. The base oil is polyalphaolefin PAO100; the thickener is ASE-60 polyurea thickener; the antioxidant is a mixture of antioxidant and anti-aging agent T-531 in equal mass; the rust inhibitor is T706 rust inhibitor; and the average particle size of the nano-tungsten disulfide is 100 nm. Step S5: Add 1 / 2 weight of base oil and thickener to the reactor and stir and mix for 3 hours at 120°C and 600 r / min. Then, heat to 160°C and continue stirring and mixing for 50 minutes. Then, heat to 200°C and continue stirring and mixing for 20 minutes. Then, cool to 120°C and add the remaining base oil, organophosphorus nitrogen polyfluorine modifier, antioxidant, rust inhibitor and nano tungsten disulfide and continue stirring and mixing for 2 hours. Then, cool to room temperature to obtain a grease composition with excellent heat resistance and stability.

[0025] Comparative Example 1: This comparative example illustrates a method for preparing a lubricating grease composition with excellent heat resistance and stability, comprising the following steps: Step S1: Weigh out 86 parts by weight of base oil, 16 parts by weight of thickener, 1.6 parts by weight of antioxidant, 1.5 parts by weight of rust inhibitor, and 1.2 parts by weight of nano-tungsten disulfide, and set aside. The base oil is polyalphaolefin PAO100; the thickener is ASE-60 polyurea thickener; the antioxidant is a mixture of antioxidant and anti-aging agent T-531 in equal mass; the rust inhibitor is T706 rust inhibitor; and the average particle size of the nano-tungsten disulfide is 100 nm. Step S2: Add 1 / 2 weight of base oil and thickener to the reactor and stir and mix at 120°C and 600 r / min for 3 hours. Then, heat to 160°C and continue stirring and mixing for 50 minutes. Then, heat to 200°C and continue stirring and mixing for 20 minutes. Then, cool to 120°C and add the remaining base oil, antioxidant, rust inhibitor and nano tungsten disulfide and continue stirring and mixing for 2 hours. Then, cool to room temperature to obtain a grease composition with excellent heat resistance and stability.

[0026] Comparative Example 2: This comparative example illustrates a method for preparing a lubricating grease composition with excellent heat resistance and stability, comprising the following steps: Step S1: Weigh out 86 parts by weight of base oil, 9 parts by weight of 4-trifluoromethylaniline, 16 parts by weight of thickener, 1.6 parts by weight of antioxidant, 1.5 parts by weight of rust inhibitor, and 1.2 parts by weight of nano-tungsten disulfide, and set aside. The base oil is polyalphaolefin PAO100; the thickener is ASE-60 polyurea thickener; the antioxidant is a mixture of antioxidant and anti-aging agent T-531 in equal mass; the rust inhibitor is T706 rust inhibitor; and the average particle size of the nano-tungsten disulfide is 100 nm. Step S2: Add 1 / 2 weight of base oil and thickener to the reactor and stir and mix for 3 hours at 120°C and 600 r / min. Then, heat to 160°C and continue stirring and mixing for 50 minutes. Then, heat to 200°C and continue stirring and mixing for 20 minutes. Then, cool to 120°C and add the remaining base oil, 4-trifluoromethylaniline, antioxidant, rust inhibitor and nano-tungsten disulfide and continue stirring and mixing for 2 hours. Then, cool to room temperature to obtain a grease composition with excellent heat resistance and stability.

[0027] Comparative Example 3: This comparative example illustrates a method for preparing a lubricating grease composition with excellent heat resistance and stability, comprising the following steps: Step S1: Weigh out 86 parts by weight of base oil, 9 parts by weight of DOPO, 16 parts by weight of thickener, 1.6 parts by weight of antioxidant, 1.5 parts by weight of rust inhibitor, and 1.2 parts by weight of nano-tungsten disulfide, and set aside. The base oil is polyalphaolefin PAO100; the thickener is ASE-60 polyurea thickener; the antioxidant is a mixture of antioxidant and anti-aging agent T-531 in equal mass; the rust inhibitor is T706 rust inhibitor; and the average particle size of the nano-tungsten disulfide is 100 nm. Step S2: Add 1 / 2 weight of base oil and thickener to the reactor and stir and mix for 3 hours at 120°C and 600 r / min. Then, heat to 160°C and continue stirring and mixing for 50 minutes. Then, heat to 200°C and continue stirring and mixing for 20 minutes. Then, cool to 120°C and add the remaining base oil, DOPO, antioxidant, rust inhibitor and nano tungsten disulfide and continue stirring and mixing for 2 hours. Then, cool to room temperature to obtain a grease composition with excellent heat resistance and stability.

[0028] The grease compositions of Examples 1-3 and Comparative Examples 1-3 with excellent heat resistance stability were subjected to performance tests, and the test results are shown in the table below:

[0029] Referring to the data in the table above, and based on the comparison between Examples 1-3 and Comparative Examples 1-3, it can be seen that the addition of organophosphorus nitrogen polyfluorine modifiers can significantly improve the lubrication performance and heat resistance of the grease composition, and the final grease composition has excellent lubrication performance and heat resistance stability.

[0030] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0031] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in this application, they should all fall within the protection scope of the present invention.

Claims

1. A lubricating grease composition with excellent heat resistance and stability, characterized in that, Includes the following components by weight: The composition includes 78-86 parts base oil, 1-9 parts organophosphorus nitrogen polyfluorine modifier, 12-16 parts thickener, 0.8-1.6 parts antioxidant, 0.7-1.5 parts rust inhibitor, and 0.6-1.2 parts nano tungsten disulfide. The organophosphorus nitrogen polyfluorine modifier is prepared by the following steps: Step a1: 2,5-Dibromobenzene-1,4-dicarboxaldehyde, 4-trifluoromethylphenylboronic acid, tetra(triphenylphosphine)palladium, sodium carbonate, toluene and deionized water were stirred and reacted. After the reaction was completed, the reaction product was cooled and then extracted with ethyl acetate. The extracts were combined, washed and dried, then filtered under vacuum. The filtrate was evaporated by rotary evaporation to obtain dialdehyde polyfluoride. Step a2: The dialdehyde polyfluoride compound, 4-trifluoromethylaniline and ethanol were stirred and reacted. After the reaction was completed, the reaction product was cooled and then vacuum filtered. The filter cake was washed and dried to obtain the Schiff base polyfluoride compound. Step a3: Stir the Schiff base polyfluoride compound, DOPO and ethanol to react. After the reaction is complete, cool the reaction product and then filter it under vacuum. Recrystallize the filter cake with N,N-dimethylformamide to obtain the organophosphorus nitrogen polyfluoride modifier.

2. The lubricating grease composition with excellent heat resistance and stability according to claim 1, characterized in that, In step a1, the ratio of 2,5-dibromobenzene-1,4-dicarboxaldehyde, 4-trifluoromethylphenylboronic acid, tetrakis(triphenylphosphine)palladium, sodium carbonate, toluene, and deionized water is 10 mmol: 20 mmol: 0.2-0.3 g: 25-30 mmol: 40-50 mL: 10-15 mL; in step a2, the ratio of dialdehyde polyfluoride, 4-trifluoromethylaniline, and ethanol is 10 mmol: 20 mmol: 60-70 mL; and in step a3, the ratio of Schiff base polyfluoride, DOPO, and ethanol is 10 mmol: 20 mmol: 90-100 mL.

3. A method for preparing a lubricating grease composition with excellent heat resistance and stability as described in any one of claims 1-2, characterized in that, Includes the following steps: Step 1: Weigh out 78-86 parts of base oil, 1-9 parts of organophosphorus nitrogen polyfluorine modifier, 12-16 parts of thickener, 0.8-1.6 parts of antioxidant, 0.7-1.5 parts of rust inhibitor, and 0.6-1.2 parts of nano tungsten disulfide according to the following weight proportions, and set aside for later use; Step 2: Add 1 / 2 weight of base oil and thickener to the reaction vessel and stir and mix for 1-3 hours at a temperature of 100-120℃ and a stirring rate of 500-600 r / min. Then, raise the temperature to 150-160℃ and continue stirring and mixing for 30-50 minutes. After that, raise the temperature to 180-200℃ and continue stirring and mixing for 10-20 minutes. Then, lower the temperature to 100-120℃ and add the remaining base oil, organophosphorus nitrogen polyfluorine modifier, antioxidant, rust inhibitor, and nano tungsten disulfide. Continue stirring and mixing for 1-2 hours. After that, cool to room temperature to obtain a grease composition with excellent heat resistance and stability.

4. The method for preparing a lubricating grease composition with excellent heat resistance and stability according to claim 3, characterized in that, The base oil is polyalphaolefin PAO100.

5. The method for preparing a lubricating grease composition with excellent heat resistance and stability according to claim 3, characterized in that, The thickener is ASE-60 polyurea thickener.

6. The method for preparing a lubricating grease composition with excellent heat resistance and stability according to claim 3, characterized in that, The antioxidant is a mixture of antioxidant and anti-aging agent T-531 in equal mass.

7. The method for preparing a lubricating grease composition with excellent heat resistance and stability according to claim 3, characterized in that, The rust inhibitor is T706 rust inhibitor.

8. The method for preparing a lubricating grease composition with excellent heat resistance and stability according to claim 3, characterized in that, The average particle size of the nano-tungsten disulfide is 100 nm.

9. The application of a grease composition with excellent heat resistance and stability prepared by a method according to any one of claims 3-8 in the lubrication of humanoid robots and high-speed bearings.

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