Anti-ultraviolet radiation antifriction and antiwear lubricating grease composition

Abstract

The invention discloses an anti-ultraviolet radiation antifriction wear-resistant lubricating grease composition, which relates to the technical field of lubrication, can be used under the mechanical working condition of sunlight or ultraviolet irradiation, and is characterized by comprising the following components in percentage by weight based on the total weight of the components: 60-90 wt% of base oil, 5-35 wt% of a thickening agent, 0.1-10 wt% of a beta-diketone organic molybdenum compound, 0.1-10 wt% of an antioxidant, 0.1-10 wt% of a lubricant and 0.1-10 wt% of a lubricant. 0.5 wt%-5wt% of an extreme pressure anti-wear additive; according to the lubricating grease composition, the beta-diketone organic molybdenum complex and the extreme pressure anti-wear agent are innovatively selected to be compounded for use, and the specific combination can absorb and reflect ultraviolet rays and prevent the lubricating grease from being oxidized and aged, so that the lubricating grease composition has ultraviolet radiation resistance, and meanwhile, the lubricating grease composition also shows excellent antifriction and anti-wear characteristics.

Description

Technical field:

[0001] The invention relates to the technical field of lubrication, in particular to an anti-ultraviolet radiation friction-reducing and anti-wear grease composition. The composition can be used in mechanical working conditions irradiated by sunlight or ultraviolet light. Background technology:

[0002] Grease is an indispensable lubricant for the operation of various machines. Among all lubricants, grease has unique properties that cannot be replaced by others. It is a lubricant with non-Newtonian fluid characteristics, which has the functions of lubrication, rust prevention and sealing. Grease is a semi-solid colloidal dispersion system formed by dispersing a thickener into a base oil, and its microstructure is a highly entangled fiber mesh structure. With the continuous improvement and development of industrial technology, lubrication conditions are becoming more and more harsh, and more and more parts are using grease, resulting in an increasing demand for grease performance, especially the aging and deterioration of grease during use. Ultraviolet rays, oxygen, heat, etc. in the environment will cause grease to age. Aging will not only shorten the service life of the grease, but also the substances produced during the aging process may corrode the equipment.

[0003] Ultraviolet light has a significant impact on the chemical bonds of the base oil and thickener of grease, which in turn seriously affects the performance of the grease. Traditional greases are prone to performance degradation under long-term exposure to ultraviolet rays and cannot meet the needs of certain outdoor application scenarios. In order to solve this problem, there is an increasing demand in the market for greases with anti-UV radiation properties, which can maintain excellent performance under ultraviolet exposure conditions. The core of anti-UV radiation grease is to add anti-UV additives so that it can effectively absorb or reflect ultraviolet rays, thereby protecting the grease matrix from damage by ultraviolet rays. However, in actual applications, selecting suitable anti-UV additives and base oils, and ensuring their uniform distribution and long-term stability in greases, is an important challenge in technical development. In addition, anti-UV additives must have good compatibility with other components of the grease and not affect its lubrication performance, antioxidant properties and corrosion resistance.

[0004] β-diketone compounds are compounds containing 1,3-dicarbonyl structures. They are an important class of oxygen-containing ligands with conjugated structures. By changing the linked substituent groups, ligands ranging from chain to ring, from bidentate to multidentate can be obtained. They can form stable metal complexes with most metals. At the same time, due to their special chemical structure, β-diketone compounds can absorb ultraviolet rays and dissipate their energy in a harmless way, and have a photostabilizing effect, thereby protecting materials from damage by ultraviolet rays. They are often used to prepare antioxidants, anti-ultraviolet agents, anti-aging agents, etc.

[0005] Organic molybdenum is one of the most widely used lubricating materials. It is a grease additive with excellent tribological properties. Its tribological properties mainly come from the formation of a molybdenum-containing composite protective film on the friction surface. Because it greatly improves the mechanical efficiency and fuel economy of the engine, it has been widely used in the automotive industry, heavy industrial machinery and aerospace fields. Molybdenum disulfide (MoS2), molybdenum dialkyl dithiocarbamate (MoDTC), and molybdenum dialkyl dithiophosphate (MoDDP) are the most common molybdenum compounds used as lubricating materials. However, long-term use of additives containing high concentrations of S and P elements will corrode equipment and pollute the environment. Therefore, the design and synthesis of low-sulfur and phosphorus organic molybdenum additives is particularly important and is one of the development trends of environmentally friendly lubricating materials in the future.

[0006] Therefore, in order to solve the above problems, the present invention selects to add β-diketone organic molybdenum compounds to provide an ultraviolet radiation-resistant antifriction and antiwear grease composition, which has good stability under ultraviolet radiation conditions and maintains efficient antifriction and antiwear properties. Summary of the invention:

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] An anti-ultraviolet radiation anti-friction and anti-wear grease composition, characterized in that, based on the total weight of the components, it comprises the following components in percentage by weight:

[0009] Base oil: 60wt%~90wt%

[0010] Thickener: 5wt%~35wt%

[0011] β-diketone organic molybdenum compound: 0.1wt%~10wt%

[0012] Extreme pressure and anti-wear additives: 0.5wt% to 5wt%.

[0013] Further settings are as follows:

[0014] Preferably, the base oil is one of synthetic base oil poly-α-olefin, hydrogenated mineral base oil, ester oil or polyether oil.

[0015] Preferably, the thickener is one of a polyurea thickener, a lithium-based thickener, a calcium-based thickener or an aluminum-based thickener.

[0016] Preferably, the β-diketone organic molybdenum compound is MoO2(R1COCHCOR2)2:

[0017]

[0018] In the formula: R1 and R2 can be independently selected from one of an alkyl group, an aryl group, an aralkyl group and a cycloalkyl group.

[0019] Preferably, the β-diketone organic molybdenum compound is selected from one or more of the following compounds: MoO2(C6H5COCHCOC6H5)2, MoO2(C6H5COCHCOCH3)2, MoO2(CH3COCHCOCH3)2, MoO2(C6H5CH3OCOCHCOC6H5CH3O)2.

[0020] Preferably, the β-diketone organic molybdenum compound is obtained by coordination of a β-diketone organic group R1COCHCOR2 and a molybdate.

[0021] Preferably, the extreme pressure and anti-wear additive may be one or more of dialkyl dithiophosphates, dialkyl dithiocarbamates, isobutylene sulfide, tetramethylthiuram disulfide, mercaptothiadiazole, organic phosphates or organic borates.

[0022] The present invention also provides a method for preparing an anti-ultraviolet radiation anti-friction and anti-wear grease composition, which is characterized by: (1) mixing the components, heating to 80-250°C and stirring to obtain a uniform mixture; and (2) cooling the mixture and then grinding it to obtain the anti-ultraviolet radiation anti-friction and anti-wear grease composition.

[0023] Preferably, the stirring in step (1) has a stirring rate of 100 rpm / min to 2000 rpm / min and a stirring time of 0.5 to 2 h.

[0024] Preferably, in the grinding of step (2), the grinding equipment is selected from one of the following: a colloid mill, a three-roll mill or a high shear mixer, the grinding temperature is 20 to 60° C., the grinding time is 30 to 120 min, and the grinding number is 3 to 5 times.

[0025] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0026] (1) Significant anti-ultraviolet radiation performance and anti-friction and anti-wear properties: The present invention innovatively selects a β-diketone organic molybdenum complex and an extreme pressure anti-wear agent for compound use. This specific combination can absorb and reflect ultraviolet rays, prevent the oxidation and aging of the grease, and make it have anti-ultraviolet radiation performance. At the same time, the grease composition also exhibits excellent anti-friction and anti-wear properties.

[0027] (2) Significant mechanical stability: The grease composition is not easily softened or hardened under high shear conditions before and after ultraviolet irradiation, thus maintaining the rheological stability of the grease during use.

[0028] (3) Stable chemical properties: The grease composition maintains excellent chemical stability under harsh conditions such as high temperature and high pressure before and after ultraviolet irradiation, and is not easily oxidized, decomposed or deteriorated.

[0029] (4) Environmental friendliness: The additive system used in the present invention does not contain harmful heavy metals and organic solvents, is environmentally friendly, complies with environmental protection regulations, and has good environmental friendliness.

[0030] (5) Simple process: The mixed grinding method is simple and easy to operate. It does not require complicated equipment and conditions during the production process, which can effectively reduce production costs and improve production efficiency. Description of the drawings:

[0031] Figure 1 The UV absorption spectra of grease compositions A and A1 before and after two weeks of UV radiation.

[0032] Figure 2 The UV absorption spectra of grease compositions B and B1 before and after two weeks of UV radiation.

[0033] Figure 3 The UV absorption spectra of grease compositions C and C1 before and after two weeks of UV radiation. Specific implementation method:

[0034] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] In the embodiment of the present invention, each performance detection method is as follows:

[0036] Tribological performance testing: The tribological performance testing method of grease composition complies with standard GB3142-82.

[0037] Anti-ultraviolet performance test: The grease composition was evenly applied on a glass slide, placed in a dark box irradiated with ultraviolet light, and taken out after irradiation for 2 weeks. The ultraviolet absorption spectrum of the grease composition before and after ultraviolet radiation was tested using an ultraviolet-visible spectrophotometer.

[0038] Cone penetration test: The cone penetration performance test method of grease composition shall comply with the standard GB / T 269-2023.

[0039] Copper sheet corrosion detection: The test method for the copper sheet corrosion performance of grease compositions shall comply with standard GB 5096-2017.

[0040] Dropping point test: The dropping point performance test method of grease composition shall comply with standard GB 4929-1985.

[0041] Copper mesh oil separation rate detection: The performance test method of the copper mesh oil separation rate of the grease composition shall comply with the standard NB / SH / T0324-2010.

[0042] Evaporation test: The evaporation performance test method of grease composition shall comply with standard SH / T 0337-1992.

[0043] Unless otherwise specified, the components in the embodiments of the present invention refer to known products or commercially available products, such as:

[0044] The polyurea thickener may be DPU-AS polyurea thickener produced by Shandong Red Star Chemical Co., Ltd.

[0045] The fatty acid lithium soap thickener can be AMKE lithium soap powder produced by Shenzhen Aisek Lubricating Materials Co., Ltd.

[0046] The composite aluminum-based thickener can be a commercially available product, or can be prepared by the following method: aluminum isopropoxide: benzoic acid: stearic acid are mixed in a molar ratio of 1:3:3, and the composite aluminum-based thickener is obtained by reaction.

[0047] The β-diketone organic molybdenum compound (MDBM) in the embodiment of the present invention is prepared by the following method: 3.38 g of dibenzoylmethane is dissolved in 50 ml of anhydrous ethanol, and 1.09 g of sodium molybdate hydrate is added to a colorless solution in 0.5 mmol of hydrochloric acid to form a yellow precipitate. After the reaction, the solution is filtered and separated to obtain a yellow solid, which is then washed with ethanol and dried in vacuum at 60° C. to obtain a β-diketone organic molybdenum compound MoO2(C6H5COCHCOC6H5)2.

[0048]

[0049] Embodiment 1:

[0050] 700 g of PAO6 base oil, 80 g of composite aluminum-based thickener, 25 g of β-diketone organic molybdenum compound (MDBM) and 20 g of zinc dialkyl dithiophosphate (ZDDP) were mixed and stirred at 200°C for 0.5 h at a speed of 500 rpm / min to obtain a uniform mixture. After the mixture was cooled to room temperature, it was ground three times with a three-roll mill to obtain a grease composition marked as A.

[0051] Comparative Example 1:

[0052] The preparation method is the same as that of Example 1, except that the formula does not contain MDBM and ZDDP. The prepared grease composition is marked as A1.

[0053] Performance Test:

[0054] The grease compositions prepared in Example 1 and Comparative Example 1 were tested for anti-ultraviolet and tribological properties, respectively. The results are shown in Table 1.

[0055] Table 1

[0056] Performance Indicators <![CDATA[Comparative Example 1 (A1)]]> Example 1 (A) Coefficient of friction (ACOF) 0.1172 0.0685 Wear spot diameter (WSD / mm) 0.54 0.35 .

[0057] Embodiment 2:

[0058] 700 g of PAO6 base oil, 80 g of fatty acid lithium soap thickener, 25 g of β-diketone organic molybdenum compound (MDBM) and 20 g of tetrabutylthiuram disulfide (TBTD) were mixed and stirred at 190°C for 0.5 h at a speed of 500 rpm / min to obtain a uniform mixture. After the mixture was cooled to room temperature, it was ground three times with a three-roll mill to obtain a grease composition marked as B.

[0059] Comparative Example 2:

[0060] The preparation method is the same as that of Example 2, except that the formula does not contain MDBM and TBTD. The prepared grease composition is marked as B1.

[0061] Performance Test:

[0062] The grease compositions prepared in Example 2 and Comparative Example 2 were tested for their anti-ultraviolet and tribological properties. The results are shown in Table 2.

[0063] Table 2

[0064]

[0065]

[0066] .

[0067] Embodiment 3:

[0068] 450 g of mineral oil 150BS base oil, 50 g of polyurea thickener, 10 g of molybdenum acetylacetonate and 10 g of zinc dialkyl dithiophosphate (ZDDP) were mixed and stirred at 210°C for 1 hour at a speed of 500 rpm / min to obtain a uniform mixture. After the mixture was cooled to room temperature, it was ground three times with a three-roll mill to obtain a grease composition marked as C.

[0069] Comparative Example 3:

[0070] The preparation method is the same as that of Example 2, except that the formula does not contain molybdenum acetylacetonate and ZDDP. The prepared grease composition is marked as C1.

[0071] Performance Test:

[0072] The grease compositions prepared in Example 3 and Comparative Example 3 were tested for their anti-ultraviolet and tribological properties. The results are shown in Table 3.

[0073] Table 3

[0074] Performance Indicators <![CDATA[Comparative Example 3 (C1)]]> Example 3 (C) Coefficient of friction (ACOF) 0.1190 0.0632 Wear spot diameter (WSD / mm) 0.55 0.35 .

[0075] Anti-ultraviolet performance test:

[0076] The grease compositions prepared in Examples 1-3 and Comparative Examples 1-3 were tested for their UV absorption spectra before and after two weeks, and their related properties before and after two weeks of treatment under UV radiation, according to the aforementioned UV resistance testing method. Figure 1-3 , as shown in Table 4:

[0077] Table 4. Comparison of relevant properties of grease before and after two weeks of treatment in UV radiation environment

[0078]

[0079]

[0080] Depend on Figure 1-3 , It can be seen from Table 4 that:

[0081] (1) From the test data, it can be seen that the cone penetration of the embodiment before and after ultraviolet radiation changes little, which shows that the grease composition has a certain hardness stability. The cone penetration of the comparative example decreases significantly, indicating that the hardness of the grease increases and becomes harder after ultraviolet radiation.

[0082] (2) The copper sheet corrosion test results show that the embodiment maintains a corrosion level of 1b before and after ultraviolet radiation, while the comparative embodiment has a significantly increased corrosion.

[0083] (3) In the dropping point test, the dropping point of the examples slightly decreased, but still remained at a high level, indicating that the thermal stability of the grease composition was good. In contrast, the dropping point of the comparative examples decreased significantly, indicating poor thermal stability.

[0084] (4) The change in the oil separation rate of the copper mesh shows that the oil separation rate of the embodiment changes little after ultraviolet radiation, showing good structural stability. The oil separation rate of the comparative example increases significantly, reflecting that its structural stability is poor and it is easy to separate oil after ultraviolet radiation.

[0085] (5) The results of the evaporation test show that the evaporation of the examples remains stable at high temperatures, has low volatility, and exhibits excellent durability. The evaporation of the comparative examples increases significantly, indicating that these greases have high volatility at high temperatures and are easy to evaporate.

[0086] (6) The ultraviolet absorption spectrum test results show that the ultraviolet absorption of the grease composition of the embodiment is higher than that of the comparative example before and after ultraviolet radiation, indicating that the grease composition of the embodiment has strong anti-ultraviolet radiation performance. Therefore, the various properties of the grease composition of the embodiment show good stability before and after ultraviolet radiation, proving that the grease composition has anti-ultraviolet radiation performance.

[0087] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments.

Claims

1. An anti-ultraviolet radiation anti-friction and anti-wear grease composition, characterized in that: The total weight of each component includes the following by weight percentage: composition: Base oil: 60%~90% Thickener: 5%~35% β-diketone organic molybdenum compound: 0.1%~10% Extreme pressure and anti-wear additives: 0.5% to 5%.

2. The anti-ultraviolet radiation anti-friction and anti-wear grease composition according to claim 1, characterized in that: The base oil is one of synthetic base oil polyalphaolefin, hydrogenated mineral base oil, ester oil or polyether oil.

3. The anti-ultraviolet radiation anti-friction and anti-wear grease composition according to claim 1, characterized in that: The thickener is one of a polyurea thickener, a lithium-based thickener, a calcium-based thickener or an aluminum-based thickener.

4. The anti-ultraviolet radiation anti-friction and anti-wear grease composition according to claim 1, characterized in that: The β-diketone organic molybdenum compound is MoO2(R1COCHCOR2)2, wherein: R1 and R2 can be independently selected from one of an alkyl group, an aryl group, an aralkyl group and a cycloalkyl group.

5. The anti-ultraviolet radiation anti-friction and anti-wear grease composition according to claim 4, characterized in that: The β-diketone organic molybdenum compound is selected from one or more of the following compounds: MoO2(C6H5COCHCOC6H5)2, MoO2(C6H5COCHCOCH3)2, MoO2(CH3COCHCOCH3)2, MoO2(C6H5CH3OCOCHCOC6H5CH3O)2.

6. The anti-ultraviolet radiation anti-friction and anti-wear grease composition according to claim 4, characterized in that: The β-diketone organic molybdenum compound is obtained by coordinating a β-diketone organic group R1COCHCOR2 with a molybdate radical.

7. The anti-ultraviolet radiation anti-friction and anti-wear grease composition according to claim 1, characterized in that: The extreme pressure and anti-wear additive is one or more of dialkyl dithiophosphate, dialkyl dithiocarbamate, isobutylene sulfide, tetramethylthiuram disulfide, mercaptothiadiazole, organic phosphate or organic borate.

8. A method for preparing the anti-ultraviolet radiation anti-friction and anti-wear grease composition according to claim 1, characterized in that: The following steps are involved: (1) mixing the components, heating them to 80-250° C. and stirring them to obtain a uniform mixture; (2) cooling the mixture, and then grinding it to obtain an anti-ultraviolet radiation anti-friction and anti-wear grease composition.

9. The method for preparing the anti-ultraviolet radiation anti-friction and anti-wear grease composition according to claim 8, characterized in that: The stirring in step (1) has a stirring rate of 100 rpm / min to 2000 rpm / min and a stirring time of 0.5 to 2 h.

10. The method for preparing the anti-ultraviolet radiation anti-friction and anti-wear grease composition according to claim 8, characterized in that: In the grinding of step (2), the grinding equipment is selected from one of the following: a colloid mill, a three-roll mill or a high shear mixer, the grinding temperature is 20 to 60° C., the grinding time is 30 to 120 min, and the grinding times are 3 to 5 times.

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