An antiwear grease composition and a preparation method thereof

Abstract

This application relates to the field of lubricating compositions, and specifically discloses an anti-wear grease composition and a preparation method thereof. An anti-wear grease composition comprises: 45 - 60 parts of calcium sulfonate, 60 - 80 parts of oil, 2 - 6 parts of alcohol, 2 - 5 parts of boric acid-modified nano filler, 2 - 6 parts of surfactant, 1 - 2 parts of antioxidant, 1 - 5 parts of chitosan quaternary ammonium salt-modified elastic microparticles, 20 - 40 parts of water, 15 - 25 parts of emulsifier, and 1 - 2 parts of defoamer; the preparation method is as follows: mix calcium sulfonate and oil, add surfactant and mix evenly to obtain a preliminary mixture; add alcohol, boric acid-modified nano filler, chitosan quaternary ammonium salt-modified elastic microparticles, water, and emulsifier and mix to obtain a mixed material; heat the mixed material to 180 - 190 °C and keep it for 5 - 8 min, then cool it to 90 - 100 °C, add defoamer and antioxidant and mix evenly, and obtain the finished product through homogenization and degassing; it has the advantages of good extreme pressure and anti-wear properties and high stability.

Description

Technical Field

[0001] The present application relates to the field of lubricating compositions, and more specifically, it relates to an anti-wear grease composition and a preparation method thereof. Background Art

[0002] Grease is an oily semi-solid used for the friction parts of machinery to play a lubricating and sealing role; it can also be used on the metal surface to play a role in filling pores and preventing rust.

[0003] Among them, the complex calcium sulfonate grease has a lower friction coefficient and better lubricating performance, can reduce friction and wear during the operation of mechanical equipment, and has a certain high-temperature stability. It can still maintain stable lubricating performance in a high-temperature environment, and is not prone to adverse reactions such as oxidation and decomposition, ensuring the normal operation of mechanical equipment.

[0004] However, the lubricating stability of the complex calcium sulfonate grease in the prior art is poor, and the extreme pressure and anti-wear properties are poor. In applications with high requirements for temperature and load capacity, the extreme pressure and anti-wear performance still need to be further improved.

[0005] Therefore, it is urgent to develop a grease composition with good extreme pressure and anti-wear properties and high stability, broaden the versatility of the existing complex calcium sulfonate grease, enable the grease to be widely used in various mechanical equipment, and even in helicopters, to meet the requirement of multi-purpose use of one grease. Summary of the Invention

[0006] In order to develop a grease composition with good extreme pressure and anti-wear properties and stable performance, broaden the versatility of the existing complex calcium sulfonate grease, enable the grease to be widely used in various mechanical equipment, and even in helicopters, to meet the requirement of multi-purpose use of one grease, the present application provides an anti-wear grease composition and a preparation method thereof.

[0007] In a first aspect, the present application provides an anti-wear grease composition, adopting the following technical solution:

[0008] An anti-wear grease composition comprising the following raw materials in parts by weight: 45 - 60 parts of calcium sulfonate, 60 - 80 parts of oil, 2 - 6 parts of alcohol, 2 - 5 parts of boric acid-modified nano filler, 2 - 6 parts of surfactant, 1 - 2 parts of antioxidant, 1 - 5 parts of chitosan quaternary ammonium salt-modified elastic microparticles, 20 - 40 parts of water, 15 - 25 parts of emulsifier, and 1 - 2 parts of defoamer.

[0009] By adopting the above technical solution, calcium sulfonate, boric acid-modified nano-fillers, and chitosan quaternary ammonium salt-modified elastic microparticles are combined. Calcium sulfonate can reduce the direct contact between metals and lower wear under conditions of high mechanical load and high rotational speed. By utilizing the hydroxyl groups in boric acid and the amino and carboxyl groups in chitosan quaternary ammonium salt, it is convenient to form a stable lubricating film, thereby reducing friction and wear. Combining with the compressive and wear-resistant effects of nano-fillers and the elastic buffering effect of elastic particles, it further resists and buffers the high pressure exerted on mechanical equipment, disperses the pressure-bearing points, and further reduces the wear between metals, thus improving the wear resistance of the grease.

[0010] Boric acid-modified nano-fillers, chitosan quaternary ammonium salt-modified elastic microparticles, alcohol, and emulsifier are combined. Boric acid and chitosan quaternary ammonium salt are soluble in water. The hydroxyl groups in boric acid are convenient for attracting and connecting with the amino groups in chitosan quaternary ammonium salt. Combining with the hydroxyl groups of alcohol, it further constructs a connection network, enabling the nano-fillers and elastic microparticles to come into contact with each other. When under pressure, through the buffering effect of elastic microparticles and the compressive effect of nano-fillers, it further improves the extreme pressure and wear resistance of the grease; under the action of the emulsifier, the boric acid-modified nano-fillers and chitosan quaternary ammonium salt-modified elastic microparticles are evenly dispersed in the oil. Combining with promoters and specific surfactants, it improves the uniformity of the grease, ensuring the lubricating effect and stability of the grease.

[0011] Preferably, the calcium sulfonate is prepared from calcium sulfonate microparticles, phosphatidylserine, and polyvinyl alcohol solution with a mass ratio of 1:0.05 - 0.1:0.1 - 0.25.

[0012] By adopting the above technical solution, after being treated with phosphatidylserine and polyvinyl alcohol solution, the calcium sulfonate microparticles utilize the lipophilic group of phosphatidylserine to be convenient for connecting with oil, and utilize the hydrophilic groups of phosphatidylserine and polyvinyl alcohol to be convenient for connecting with boric acid-modified nano-fillers and chitosan quaternary ammonium salt-modified elastic microparticles, thereby realizing the formation of a connection network between calcium sulfonate and nano-fillers and elastic microparticles. The connection network can form a lubricating film with low friction, and the connection network is evenly dispersed, which can further improve the wear resistance uniformity and stability of the grease.

[0013] Preferably, the boric acid-modified nano-fillers are prepared from boric acid solution, hydroxyapatite microspheres, and boron nitride microspheres with a mass ratio of 1:0.5 - 1:0.2 - 0.5.

[0014] By adopting the above technical solutions, boric acid solution adheres to the surfaces of hydroxyapatite microspheres and boron nitride microspheres. Utilizing the hydroxyl groups in boric acid and coordinating with the hydroxyl groups on the surface of hydroxyapatite microspheres, the connection effect between the boric acid-modified nano-fillers and chitosan quaternary ammonium salt-modified elastic microparticles and calcium sulfonate is further improved. The existence of the connection network can further balance the extreme pressure, and in combination with the filling effects of hydroxyapatite and boron nitride, the formed lubricating film has high strength and stability, can reduce friction and wear while improving the abrasion resistance and stability of the grease.

[0015] Preferably, the average porosity of the hydroxyapatite microspheres is 10 - 20%, the average particle size of the hydroxyapatite microspheres is 40 - 100 nm, and the average particle size of the boron nitride microspheres is 10 - 40 nm.

[0016] By adopting the above technical solutions, by limiting the porosity of the hydroxyapatite microspheres, while ensuring the strength of the hydroxyapatite, the adsorption amount of boric acid solution can also be increased. With a high boric acid content on the surface of the hydroxyapatite microspheres, it promotes the formation of a connection network between the boric acid-modified filler, chitosan quaternary ammonium salt-modified elastic microparticles, and calcium sulfonate; in combination with the limitation of the average particle size of the spherical bodies, the spheres can flow more smoothly, reducing the frictional resistance and improving the abrasion resistance of the grease.

[0017] Preferably, the chitosan quaternary ammonium salt-modified elastic microparticles are prepared from a chitosan quaternary ammonium salt solution, polyether ether ketone microparticles, and polyimide microparticles with a mass ratio of 1:0.2 - 0.5:0.3 - 0.5.

[0018] By adopting the above technical solutions, the chitosan quaternary ammonium salt solution, polyether ether ketone microparticles, and polyimide microparticles cooperate with each other. Utilizing the viscosity of the chitosan quaternary ammonium salt solution, it adheres to the surfaces of the polyether ether ketone microparticles and polyimide microparticles. The amino groups of the chitosan quaternary ammonium salt are convenient for connecting with the hydroxyl groups and alcohols of boric acid to form a connection network, enabling the polyether ether ketone microparticles and polyimide microparticles to be dispersed near the hydroxyapatite microspheres and boron nitride microspheres. Utilizing the buffering effects of the polyether ether ketone microparticles and polyimide microparticles and in combination with the high strength of the hydroxyapatite microspheres and boron nitride microspheres, the high-pressure impact effect of the grease is further improved, and the abrasion resistance of the grease is enhanced.

[0019] Preferably, the average particle size of the polyether ether ketone microparticles is 1 - 3 μm, and the average particle size of the polyimide microparticles is 3 - 8 μm.

[0020] By adopting the above technical solutions, by limiting the particle sizes of the polyether ether ketone microparticles and polyimide microparticles to be larger than those of the hydroxyapatite microspheres and boron nitride microspheres, the force is further buffered and unloaded. After the pressure is dispersed in multiple directions, by reducing the force and in combination with the relatively high abrasion resistance of the polyether ether ketone microparticles and polyimide microparticles, the abrasion resistance of the grease is improved.

[0021] Preferably, the emulsifier is composed of glyceryl citrate and Tween 80 with a mass ratio of 1:1 - 3.

[0022] By adopting the above technical solution, glyceryl citrate contains both a hydrophilic hydroxyl group and a hydrophobic ester group. The hydrophilic group facilitates the connection with boric acid and chitosan quaternary ammonium salt, while the ester group facilitates the connection with oil, further improving the lubrication effect. Combining with the emulsifying effect of Tween 80, it improves the emulsification effect of the grease, reduces mechanical friction and wear, and improves the wear resistance while enhancing the lubrication effect.

[0023] Preferably, the alcohol is composed of isopropyl alcohol and polyethylene glycol 600 with a mass ratio of 1:1 - 2.

[0024] By adopting the above technical solution, due to the flexibility of its molecular chain, polyethylene glycol can form a smooth layered structure between the friction surfaces, forming a uniform lubricating film, effectively reducing the direct contact between the friction surfaces, thereby reducing the friction coefficient and wear rate; during the lubrication process, the hydroxyl groups of polyethylene glycol can form hydrogen bonds with water molecules, further reducing the surface friction and enhancing the lubrication effect; combined with the penetration effect of isopropyl alcohol, it further improves the lubrication effect and wear resistance of the grease.

[0025] Preferably, the surfactant is sodium dodecylbenzenesulfonate.

[0026] By adopting the above technical solution, using the solubilization effect and dispersion ability of sodium dodecylbenzenesulfonate, other components can be effectively solubilized and uniformly dispersed in the oil, thereby ensuring the uniformity and stability of the grease. And the molecular structure of sodium dodecylbenzenesulfonate contains lipophilic and hydrophilic groups, which enables it to form a lubricating film on the friction surface, reducing friction and wear, thus improving the wear resistance; at the same time, the addition of sodium dodecylbenzenesulfonate can improve the low-temperature fluidity of the grease, ensuring good lubricating performance under low-temperature conditions.

[0027] In the second aspect, the present application provides a preparation method of an anti-wear grease composition, adopting the following technical solution:

[0028] A preparation method of an anti-wear grease composition includes the following steps:

[0029] S1. Weigh calcium sulfonate and oil, mix them evenly under the condition of 80 - 90 °C, and then add the surfactant and continue to mix and stir evenly to obtain a preliminary mixture.

[0030] S2. Add alcohol, boric acid-modified nano filler, chitosan quaternary ammonium salt-modified elastic microparticles, water, and emulsifier to the preliminary mixture, heat it up to 110 - 120 °C and keep it for 60 - 80 min to obtain a mixed material.

[0031] S3. Heat the mixture to 180 - 190 °C, hold for 5 - 8 min, then cool to 90 - 100 °C, add defoamer and antioxidant, mix and stir evenly, and obtain the finished product through homogenization and degassing.

[0032] By adopting the above technical solution, the prepared grease composition has a good lubricating effect, and has excellent extreme pressure and anti-wear performance and high stability. It broadens the universality of the existing complex calcium sulfonate grease, enabling the grease to be widely used in various mechanical equipment, and even in helicopters.

[0033] In summary, the present application has the following beneficial effects:

[0034] 1. Calcium sulfonate, boric acid-modified nano-fillers, and chitosan quaternary ammonium salt-modified elastic particles are combined. Calcium sulfonate can reduce the direct contact between metals under high mechanical load and high rotational speed conditions, reduce wear. By using the hydroxyl groups in boric acid and the amino and carboxyl groups in chitosan quaternary ammonium salt, it is convenient to form a stable lubricating film, thereby reducing friction and wear. Combining with the compressive and wear-resistant effects of nano-fillers and the elastic buffering effect of elastic particles, it further resists and buffers the high pressure received by mechanical equipment, disperses the pressure bearing points, and further reduces the wear between metals, thereby improving the wear resistance of the grease.

[0035] 2. After the calcium sulfonate particles are treated with phosphatidylserine and polyvinyl alcohol solution, the lipophilic group of phosphatidylserine is convenient for connecting with oil, and the hydrophilic groups of phosphatidylserine and polyvinyl alcohol are convenient for connecting with boric acid-modified nano-fillers and chitosan quaternary ammonium salt-modified elastic particles, thereby realizing the formation of a connection network between calcium sulfonate and nano-fillers and elastic particles. The connection network can form a lubricating film with low friction, and the connection network is evenly dispersed, which can further improve the wear resistance uniformity and stability of the grease. Specific Embodiments

[0036] The following further elaborates on the present application with reference to examples.

[0037] The following raw materials are all commercially available.

[0038] Preparation Example of Calcium Sulfonate

[0039] Preparation Example 1: Calcium sulfonate is prepared by the following method:

[0040] Put polyvinyl alcohol in water and stir until it is completely dissolved to obtain a 1% (by mass) polyvinyl alcohol solution. Then, add 0.08 kg of phosphatidylserine to 0.2 kg of the polyvinyl alcohol solution and stir and mix at a rotation speed of 1000 r / min for 5 min to obtain a mixture. Spray the mixture evenly onto the surface of 1 kg of calcium sulfonate particles. The calcium sulfonate particles have a total base number in the range of 400 - 425 mg KOH / g and an average particle size of 3 μm. After drying and dispersion, the finished calcium sulfonate is obtained.

[0041] Preparation Example 2: The difference between this preparation example and Preparation Example 1 is that:

[0042] Put polyvinyl alcohol in water and stir until it is completely dissolved to obtain a 1% (by mass) polyvinyl alcohol solution. Then, add 0.05 kg of phosphatidylserine to 0.1 kg of the polyvinyl alcohol solution and stir and mix at a rotation speed of 1000 r / min for 5 min to obtain a mixture. Spray the mixture evenly onto the surface of 1 kg of calcium sulfonate particles. The average particle size of the calcium sulfonate particles is 3 μm. After drying and dispersion, the finished calcium sulfonate is obtained.

[0043] Preparation Example 3: The difference between this preparation example and Preparation Example 1 is that:

[0044] Put polyvinyl alcohol in water and stir until it is completely dissolved to obtain a 1% (by mass) polyvinyl alcohol solution. Then, add 0.1 kg of phosphatidylserine to 0.25 kg of the polyvinyl alcohol solution and stir and mix at a rotation speed of 1000 r / min for 5 min to obtain a mixture. Spray the mixture evenly onto the surface of 1 kg of calcium sulfonate particles. The average particle size of the calcium sulfonate particles is 3 μm. After drying and dispersion, the finished calcium sulfonate is obtained.

[0045] Preparation Examples of Boric Acid-Modified Nanofillers

[0046] Preparation Example 4: The boric acid-modified nanofiller is prepared by the following method:

[0047] Put boric acid in water and stir until it is completely dissolved to obtain a 15% (by mass) boric acid solution;

[0048] Mix 0.7 kg of hydroxyapatite microspheres and 0.3 kg of boron nitride microspheres and stir evenly. The average porosity of the hydroxyapatite microspheres is 20%, the average particle size of the hydroxyapatite microspheres is 80 nm, and the average particle size of the boron nitride microspheres is 20 nm. Then, evenly spray 1 kg of the boric acid solution on the surface. After drying, disperse them until the microspheres do not stick and agglomerate with each other to obtain the finished boric acid-modified nanofiller.

[0049] Preparation Example 5: The difference between this preparation example and Preparation Example 4 is that:

[0050] Mix 0.5 kg of hydroxyapatite microspheres and 0.2 kg of boron nitride microspheres evenly by stirring. The average porosity of the hydroxyapatite microspheres is 10%, the average particle size of the hydroxyapatite microspheres is 100 nm, and the average particle size of the boron nitride microspheres is 40 nm. Then, evenly spray 1 kg of boric acid solution on the surface, and after drying, disperse them so that the microspheres do not stick to each other or agglomerate, obtaining the finished boric acid-modified nano filler.

[0051] Preparation Example 6: The difference between this preparation example and Preparation Example 4 is that:

[0052] Mix 1 kg of hydroxyapatite microspheres and 0.5 kg of boron nitride microspheres evenly by stirring. The average porosity of the hydroxyapatite microspheres is 20%, the average particle size of the hydroxyapatite microspheres is 40 nm, and the average particle size of the boron nitride microspheres is 10 nm. Then, evenly spray 1 kg of boric acid solution on the surface, and after drying, disperse them so that the microspheres do not stick to each other or agglomerate, obtaining the finished boric acid-modified nano filler.

[0053] Preparation Examples of Chitosan Quaternary Ammonium Salt-Modified Elastic Microspheres

[0054] Preparation Example 7: The chitosan quaternary ammonium salt-modified elastic microspheres are prepared by the following method:

[0055] Place the chitosan quaternary ammonium salt in water and stir until it is completely dissolved to obtain a 5% (by mass) chitosan quaternary ammonium salt solution;

[0056] Mix 0.35 kg of polyetheretherketone microspheres and 0.45 kg of polyimide microspheres evenly by stirring. The average particle size of the polyetheretherketone microspheres is 2 μm, and the average particle size of the polyimide microspheres is 5 μm; then, evenly spray 1 kg of the chitosan quaternary ammonium salt solution on the surface, and after drying and dispersing, make the microspheres not stick to each other or agglomerate, obtaining the finished chitosan quaternary ammonium salt-modified elastic microspheres.

[0057] Preparation Example 8: The difference between this preparation example and Preparation Example 7 is that:

[0058] Mix 0.2 kg of polyetheretherketone microspheres and 0.3 kg of polyimide microspheres evenly by stirring. The average particle size of the polyetheretherketone microspheres is 3 μm, and the average particle size of the polyimide microspheres is 8 μm; then, evenly spray 1 kg of the chitosan quaternary ammonium salt solution on the surface, and after drying and dispersing, make the microspheres not stick to each other or agglomerate, obtaining the finished chitosan quaternary ammonium salt-modified elastic microspheres.

[0059] Preparation Example 9: The difference between this preparation example and Preparation Example 7 is that:

[0060] Mix 0.5 kg of polyether ether ketone particles and 0.5 kg of polyimide particles evenly by stirring. The average particle size of the polyether ether ketone particles is 1 μm, and the average particle size of the polyimide particles is 3 μm. Then, evenly spray 1 kg of chitosan quaternary ammonium salt solution on the surface, and after drying and dispersing until the particles do not adhere and agglomerate with each other, the finished chitosan quaternary ammonium salt modified elastic particles are obtained. Example

[0061] Example 1: An anti-wear grease composition:

[0062] 52 kg of calcium sulfonate, 70 kg of oil, 4 kg of alcohol, 3.5 kg of boric acid modified nano-filler, 4 kg of surfactant, 1 kg of antioxidant, 3 kg of chitosan quaternary ammonium salt modified elastic particles, 30 kg of water, 20 kg of emulsifier, 1 kg of defoamer; the calcium sulfonate is the calcium sulfonate prepared in Preparation Example 1, the oil is cottonseed oil, the alcohol is composed of isopropyl alcohol and polyethylene glycol 600 with a mass ratio of 1:2, the boric acid modified nano-filler is the boric acid modified nano-filler prepared in Preparation Example 4, the surfactant is sodium dodecylbenzenesulfonate, the antioxidant is antioxidant 1010, the chitosan quaternary ammonium salt modified elastic particles are the chitosan quaternary ammonium salt modified elastic particles prepared in Preparation Example 7, the emulsifier is composed of glyceryl citrate and Tween 80 with a mass ratio of 1:2, and the defoamer is polydimethylsiloxane;

[0063] The preparation method is as follows:

[0064] S1. Weigh calcium sulfonate and oil, mix them evenly under the condition of 85 °C, and then add a promoter and a surfactant and continue to mix and stir evenly to obtain a preliminary mixture.

[0065] S2. Add alcohol, boric acid modified nano-filler, chitosan quaternary ammonium salt modified elastic particles, water, and emulsifier to the preliminary mixture, heat up to 115 °C and keep it for 70 min to obtain a mixed material.

[0066] S3. Heat up the mixed material to 185 °C, keep it for 7 min, then cool it down to 95 °C, add a defoamer and an antioxidant and mix and stir evenly, and after homogenization and degassing, the finished product is obtained.

[0067] Example 2: The difference between this example and Example 1 is that:

[0068] 45 kg of calcium sulfonate, 60 kg of oil, 2 kg of alcohol, 2 kg of boric acid-modified nano filler, 1 kg of accelerator, 2 kg of surfactant, 1 kg of antioxidant, 1 kg of chitosan quaternary ammonium salt-modified elastic microparticles, 20 kg of water, 15 kg of emulsifier, 1 kg of defoamer; The calcium sulfonate is the calcium sulfonate prepared in Preparation Example 2, the oil is cottonseed oil, the alcohol is composed of isopropyl alcohol and polyethylene glycol 600 with a mass ratio of 1:1, the boric acid-modified nano filler is the boric acid-modified nano filler prepared in Preparation Example 5, the surfactant is sodium dodecylbenzenesulfonate, the antioxidant is antioxidant 1010, the chitosan quaternary ammonium salt-modified elastic microparticles are the chitosan quaternary ammonium salt-modified elastic microparticles prepared in Preparation Example 8, the emulsifier is composed of glyceryl citrate and Tween 80 with a mass ratio of 1:1, and the defoamer is polydimethylsiloxane;

[0069] The preparation method is as follows:

[0070] S1. Weigh and mix calcium sulfonate and oil, stir evenly at 80 °C, then add the accelerator and surfactant and continue to mix and stir evenly to obtain a preliminary mixture;

[0071] S2. Add alcohol, boric acid-modified nano filler, chitosan quaternary ammonium salt-modified elastic microparticles, water, and emulsifier to the preliminary mixture, heat up to 110 °C and hold for 80 min to obtain a mixed material;

[0072] S3. Heat the mixed material to 180 °C, hold for 8 min, then cool down to 100 °C, add the defoamer and antioxidant and mix and stir evenly, and then homogenize and degas to obtain the finished product.

[0073] Example 3: The difference between this example and Example 1 is that:

[0074] 60 kg of calcium sulfonate, 80 kg of oil, 6 kg of alcohol, 5 kg of boric acid-modified nano filler, 4 kg of accelerator, 6 kg of surfactant, 2 kg of antioxidant, 5 kg of chitosan quaternary ammonium salt-modified elastic microparticles, 40 kg of water, 25 kg of emulsifier, 2 kg of defoamer; The calcium sulfonate is the calcium sulfonate prepared in Preparation Example 3, the oil is cottonseed oil, the alcohol is composed of isopropyl alcohol and polyethylene glycol 600 with a mass ratio of 1:1, the boric acid-modified nano filler is the boric acid-modified nano filler prepared in Preparation Example 6, the surfactant is sodium dodecylbenzenesulfonate, the antioxidant is antioxidant 1010, the chitosan quaternary ammonium salt-modified elastic microparticles are the chitosan quaternary ammonium salt-modified elastic microparticles prepared in Preparation Example 9, the emulsifier is composed of glyceryl citrate and Tween 80 with a mass ratio of 1:3, and the defoamer is polydimethylsiloxane;

[0075] The preparation method is as follows:

[0076] S1. Weigh and mix calcium sulfonate and oil, stir evenly at 90 °C, then add the accelerator and surfactant and continue to mix and stir evenly to obtain a preliminary mixture;

[0077] S2. Add alcohol, boric acid-modified nano-fillers, chitosan quaternary ammonium salt-modified elastic microparticles, water, and emulsifier to the premix, heat up to 120 °C and hold for 60 min to obtain a mixed material.

[0078] S3. Heat up the mixed material to 190 °C, hold for 5 min, then cool down to 90 °C, add defoamer and antioxidant, mix and stir evenly, and homogenize and degas to obtain the finished product.

[0079] Example 4: The difference between this example and Example 1 is that:

[0080] In the raw materials, calcium sulfonate microparticles with the same mass are used to replace the calcium sulfonate prepared in Preparation Example 1.

[0081] Example 5: The difference between this example and Example 1 is that:

[0082] In the preparation process of the boric acid-modified nano-fillers in the raw materials, calcium carbonate with the same mass is used to replace hydroxyapatite microspheres and boron nitride microspheres, and the average particle size of calcium carbonate is 40 μm.

[0083] Example 6: The difference between this example and Example 1 is that:

[0084] In the preparation process of the emulsifier in the raw materials, glycerol citrate is not added. Comparative Example

[0085] Comparative Example 1: The difference between this comparative example and Example 1 is that:

[0086] Boric acid-modified nano-fillers and chitosan quaternary ammonium salt-modified elastic microparticles are not added to the raw materials.

[0087] Comparative Example 2: The difference between this comparative example and Example 1 is that:

[0088] In the raw materials, boric acid with the same mass is used to replace the boric acid-modified nano-fillers, and chitosan quaternary ammonium salt with the same mass is used to replace the chitosan quaternary ammonium salt-modified elastic microparticles.

[0089] Performance Detection Test

[0090] 1. Extreme Pressure Performance Detection

[0091] Prepare grease compositions by the methods of Examples 1-6 and Comparative Examples 1-2 respectively, refer to NB / SH / T0202 to detect the sintering load. The higher the sintering load, the better the extreme pressure lubricity of the grease, and record the data.

[0092] 2. Wear Resistance Detection

[0093] The grease compositions were prepared by the methods of Examples 1-6 and Comparative Examples 1-2 respectively. Referring to SH / T0204, the anti-wear performance (four-ball machine method) was detected. Under the conditions of 75 °C, 1200 r / min, 392 N, and 60 min, the scar diameter was detected and the data were recorded.

[0094] 3. Stability Detection

[0095] The grease compositions were prepared by the methods of Examples 1-6 and Comparative Examples 1-2 respectively. Referring to SH / T0324, under the conditions of 100 °C and 24 h, the oil separation on steel mesh was detected and the data were recorded. The smaller the oil separation, the better the stability.

[0096] Table 1 Performance Test Table

[0097]

[0098] Combined with Examples 1-3 and Table 1, it can be seen that the grease composition prepared in this application has a high sintering load, a small scar diameter, and a small oil separation on steel mesh, indicating that the extreme pressure and anti-wear performance of the grease is good and the stability is good.

[0099] Combined with Example 1 and Examples 4-6 and Table 1, it can be seen that in the raw materials of Example 4, calcium sulfonate prepared in Preparation Example 1 was replaced with calcium sulfonate microparticles of the same mass. Compared with Example 1, the sintering load of the grease prepared in Example 4 was lower than that of Example 1, the scar diameter was larger than that of Example 1, and the oil separation on steel mesh was larger than that of Example 1; it shows that phosphatidylserine and polyvinyl alcohol solution are combined. The lipophilic group of phosphatidylserine is convenient for connecting with oil, and the hydrophilic groups of phosphatidylserine and polyvinyl alcohol are convenient for connecting with boric acid-modified nano-fillers and chitosan quaternary ammonium salt-modified elastic microparticles, promoting the formation of a connection network of calcium sulfonate, boric acid-modified nano-fillers, and chitosan quaternary ammonium salt-modified elastic microparticles. The connection network can form a lubricating film with low friction, and the connection network is evenly dispersed, which can further improve the wear resistance uniformity of the grease.

[0100] In the preparation process of the boric acid-modified nano-fillers in the raw materials of Example 5, hydroxyapatite microspheres and boron nitride microspheres were replaced with calcium carbonate of the same mass. Compared with Example 1, the sintering load of the grease prepared in Example 5 was lower than that of Example 1, the scar diameter was larger than that of Example 1, and the oil separation on steel mesh was larger than that of Example 1; it shows that calcium carbonate has poor lubrication performance in heavy load and high temperature environments, while hydroxyapatite microspheres and boron nitride microspheres still have good lubrication effects in heavy load and high temperature environments; and calcium carbonate has poor affinity with oil, which easily affects the stability of the grease; at the same time, nano-calcium carbonate is prone to wear due to friction at high temperature, affecting the wear resistance of the grease.

[0101] In the preparation process of the emulsifier in the raw materials of Example 6, citric acid glycerol ester was not added. Compared with Example 1, the sintering load of the grease prepared in Example 6 was lower than that in Example 1, the wear scar diameter was larger than that in Example 1, and the oil separation amount of the steel mesh was larger than that in Example 1. It shows that citric acid glycerol ester contains both a hydrophilic hydroxyl group and an ester group of a hydrophobic group. The hydrophilic group facilitates the connection with boric acid and chitosan quaternary ammonium salt, while the ester group facilitates the connection with oil, further improving the lubrication effect. Combining with the emulsifying effect of Tween 80, it improves the emulsifying effect of the grease, reduces mechanical friction and wear, and improves the wear resistance and stability while enhancing the lubrication effect.

[0102] Combining Example 1 and Comparative Examples 1-2 and referring to Table 1, it can be seen that in Comparative Example 1, boric acid-modified nano-fillers and chitosan quaternary ammonium salt-modified elastic microparticles were not added to the raw materials. Compared with Example 1, the sintering load of the grease prepared in Comparative Example 1 was lower than that in Example 1, the wear scar diameter was larger than that in Example 1, and the oil separation amount of the steel mesh was larger than that in Example 1. It shows that the boric acid-modified nano-fillers and chitosan quaternary ammonium salt-modified elastic microparticles cooperate with each other. Utilizing the hydroxyl group in boric acid and the amino and carboxyl groups in chitosan quaternary ammonium salt, it is convenient to form a stable lubricating film, thereby reducing friction and wear. Combining with the compressive wear resistance effect of the nano-fillers and the elastic buffering effect of the elastic particles, it further resists and buffers the high pressure received by the mechanical equipment, disperses the pressure bearing points, and further reduces the wear between metals, thereby improving the wear resistance of the grease.

[0103] In Comparative Example 2, boric acid was used to replace the boric acid-modified nano-fillers in the raw materials with the same mass, and chitosan quaternary ammonium salt was used to replace the chitosan quaternary ammonium salt-modified elastic microparticles in the raw materials with the same mass. Compared with Example 1, the sintering load of the grease prepared in Comparative Example 2 was lower than that in Example 1, the wear scar diameter was larger than that in Example 1, and the oil separation amount of the steel mesh was larger than that in Example 1. It shows that the hydroxyl group in boric acid is convenient to attract and connect with the amino group in chitosan quaternary ammonium salt. Combining with the hydroxyl group of alcohol, it further constructs a connection network to make the nano-fillers and elastic microparticles contact each other. When under pressure, through the buffering effect of the elastic microparticles and the compressive effect of the nano-fillers, it further improves the extreme pressure wear resistance of the grease.

[0104] This specific embodiment is only an interpretation of the present application, and it is not a limitation of the present application. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. An anti-wear grease composition, characterized in that: The invention comprises the following raw materials in parts by weight: 45-60 parts of calcium sulfonate, 60-80 parts of oil, 2-6 parts of alcohol, 2-5 parts of boric acid modified nano filler, 2-6 parts of surfactant, 1-2 parts of antioxidant, 1-5 parts of chitosan quaternary ammonium salt modified elastic microparticles, 20-40 parts of water, 15-25 parts of emulsifier and 1-2 parts of defoamer; the boric acid modified nano filler is prepared from a boric acid solution, hydroxyapatite microspheres and boron nitride microspheres in a mass ratio of 1:0.5-1:0.2-0.5; the chitosan quaternary ammonium salt modified elastic microparticles are prepared from a chitosan quaternary ammonium salt solution, polyetheretherketone microparticles and polyimide microparticles in a mass ratio of 1:0.2-0.5:0.3-0.

5.

2. The anti-wear grease composition according to claim 1, characterized in that: The calcium sulfonate is prepared from calcium sulfonate particles, phosphatidylserine and polyvinyl alcohol solution in a mass ratio of 1:0.05-0.1:0.1-0.

25.

3. The anti-wear grease composition according to claim 1, characterized in that: The average porosity of the hydroxyapatite microspheres is 10-20%, the average particle size of the hydroxyapatite microspheres is 40-100 nm, and the average particle size of the boron nitride microspheres is 10-40 nm.

4. The anti-wear grease composition according to claim 1, characterized in that: The average particle size of the polyetheretherketone particles is 1-3 μm, and the average particle size of the polyimide particles is 3-8 μm.

5. The anti-wear grease composition according to claim 1, characterized in that: The emulsifier consists of glycerol citrate and Tween 80 in a mass ratio of 1:1-3.

6. The anti-wear grease composition according to claim 1, characterized in that: The alcohol consists of isopropanol and polyethylene glycol 600 in a mass ratio of 1:1-2.

7. The anti-wear grease composition according to claim 1, characterized in that: The surfactant is sodium dodecylbenzene sulfonate.

8. A method for preparing an anti-wear grease composition according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. Weigh calcium sulfonate and oil, mix them, stir them evenly at 80-90°C, then add a surfactant and continue to mix and stir them evenly to obtain a primary mixture; S2, adding alcohol, boric acid modified nanofiller, chitosan quaternary ammonium salt modified elastic particles, water, and emulsifier to the primary mixture, heating to 110-120° C. and maintaining for 60-80 min to obtain a mixture; S3. The mixture is heated to 180-190°C and maintained for 5-8 minutes, then cooled to 90-100°C, defoaming agent and antioxidant are added, mixed and stirred evenly, and the finished product is obtained after homogenization and degassing.

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