Gear oil composition and preparation method thereof

Abstract

The invention provides a gear oil composition and a preparation method thereof. The gear oil composition comprises a benzotriazole derivative, an antioxidant, an anti-wear reagent at extreme pressure, an anti-rust agent and lubricant base oil, wherein the structure of the benzotriazole derivative is as shown in formula (I): # imgabs0 #, wherein the definition of each group is as shown in the specification. The gear oil composition provided by the invention has excellent oxidation resistance, corrosion resistance and rust resistance, and can meet the requirements of GL-5 and above extreme-pressure heavy-load gear oil products.

Description

Technical Field

[0001] The present invention relates to a lubricating oil composition, and particularly to a gear oil composition and a preparation method thereof. Background Art

[0002] With the development of mechanical technology, gears heat up rapidly during operation due to accelerating rotation, resulting in an increasingly high oil temperature during work, which causes the oxidation of the oil product, accelerates the corrosion and wear of the tooth surface, and directly affects the working performance of the equipment. At a certain temperature, components such as sulfur compounds and aromatics in the oil product react with oxygen and trace water in the air to form organic acids and gums, and finally form precipitates. These precipitates will cause metal corrosion, increase gear wear, damage the gear profile, lead to a decrease in working efficiency, and even cause failures. Therefore, higher requirements are also put forward for the anti-corrosion performance of gear oils. Most of the existing technologies focus on the anti-wear performance of gear oil compositions, and the attention to their anti-corrosion performance is far from enough.

[0003] The gear oils manufactured using the existing technologies can no longer fully meet the requirements of modern gear oils. The existing technologies require a gear oil composition that should not only meet the increasingly stringent requirements of gear oils for anti-wear and anti-oxidation performance, but also have excellent anti-corrosion performance. Summary of the Invention

[0004] The present invention provides a gear oil composition and a preparation method thereof.

[0005] The gear oil composition of the present invention comprises a benzotriazole derivative, an antioxidant, an extreme pressure anti-wear agent, a rust inhibitor, and a lubricating oil base oil, wherein the structure of the benzotriazole derivative is shown in formula (I):

[0006]

[0007] In formula (I), n is an integer between 1 and 10; the R1 group is selected from C 1-20 a linear or branched alkylene group; the R2 groups in n repeating units are the same or different from each other, and are each independently selected from C 1-20 a linear or branched alkylene group; the R3 group is selected from H and C 1-20 a linear or branched alkyl group; the A groups in n repeating units are the same or different from each other, and are each independently selected from the group shown in formula (II) and the group shown in formula (III);

[0008]

[0009] In formula (II) and formula (III), * represents the bonding end bonded to formula (I);

[0010] The R4 group and the R5 group are each independently selected from H and C 1-10Straight-chain or branched-chain alkyl group.

[0011] According to the present invention, preferably, in formula (I), n is an integer between 1 and 5, and the R1 group is selected from C 1-10 Straight-chain or branched-chain alkylene group, and the R2 groups in n repeating units are each independently selected from C 1-10 Straight-chain or branched-chain alkylene group, and the R3 group is selected from H and C 1-10 Straight-chain or branched-chain alkyl group, and the R4 group and the R5 group are each independently selected from C 1-4 Straight-chain or branched-chain alkyl group.

[0012] According to the present invention, more preferably, in formula (I), n is an integer between 1 and 3, and the R1 group is selected from C 1-8 Straight-chain or branched-chain alkylene group, and the R2 groups in n repeating units are each independently selected from C 1-8 Straight-chain or branched-chain alkylene group, and the R3 group is selected from H and C 1-8 Straight-chain or branched-chain alkyl group, the R4 group and the R5 group are selected from tert-butyl group, or the R4 group is selected from tert-butyl group and the R5 group is selected from H.

[0013] According to the present invention, examples of the benzotriazole derivative may include one or more of the following structural compounds:

[0014]

[0015] According to the present invention, the preparation method of the benzotriazole derivative includes the following steps:

[0016] (1) Reacting the compound represented by formula (α) with a peroxide;

[0017]

[0018] In formula (α), n is an integer between 1 and 10; the R1 group is selected from C 1-20 Straight-chain or branched-chain alkylene group; the R2 groups in n repeating units are the same or different, and are each independently selected from C 1-20 Straight-chain or branched-chain alkylene group; the R3 group is selected from H and C 1-20 Straight-chain or branched-chain alkyl group; the A” groups in n repeating units are selected from -CH=CH-; the R4 group and the R5 group are each independently selected from H and C 1-10 Straight-chain or branched-chain alkyl group;

[0019] (2) Subjecting the reaction product of step (1) to a hydrolysis reaction;

[0020] (3) Reacting the hydrolysis reaction product of step (2) with the compound represented by formula (β), and collecting the product;

[0021]

[0022] The X group therein is selected from OH, F, Cl, Br, and I.

[0023] According to the present invention, preferably, in formula (α), n is an integer between 1 and 5, and the R1 group is selected from C 1-10 linear or branched alkylene, and the R2 groups in n repeating units are each independently selected from C 1-10 linear or branched alkylene, the R3 group is selected from H and C 1-10 linear or branched alkyl, and the R4 group and the R5 group are each independently selected from C 1-4 linear or branched alkyl.

[0024] According to the present invention, further preferably, in formula (α), n is an integer between 1 and 3, and the R1 group is selected from C 1-8 linear or branched alkylene, and the R2 groups in n repeating units are each independently selected from C 1-8 linear or branched alkylene, the R3 group is selected from H and C 1-8 linear or branched alkyl, the R4 group and the R5 group are selected from tert-butyl or the R4 group is selected from tert-butyl and the R5 group is selected from H.

[0025] According to the present invention, in step (1), the compound represented by formula (α) can be selected from cardanol and alkylated cardanol, and the alkylated cardanol can be obtained by reacting cardanol with an alkylating agent. For example, tert-butylated cardanol can be obtained by reacting cardanol with tert-butyl chloride.

[0026] According to the present invention, in step (1), the peroxide is preferably one or more of hydrogen peroxide, performic acid, peracetic acid, peroxysulfonic acid, m-chloroperbenzoic acid, tert-butyl hydroperoxide, tert-butyl peracetate, methyl ethyl ketone peroxide, benzoyl peroxide, and cyclohexanone peroxide, and more preferably one or more of hydrogen peroxide, performic acid, peracetic acid, and peroxysulfonic acid.

[0027] According to the present invention, the reaction product of step (1) can be obtained by reacting cardanol or alkylated cardanol with a peroxide, or can also be obtained by first reacting cardanol with a peroxide and then reacting with an alkylating agent.

[0028] According to the present invention, in step (2), the hydrolysis reaction is to hydrolyze the reaction product of step (1) with water, and the amount of water used is generally 20% to 200% of the mass of the reaction product of step (1).

[0029] According to the present invention, in step (3), the compound represented by formula (β) may be selected from one or more of benzotriazole-5-carboxylic acid, benzotriazole-5-carbonyl fluoride, benzotriazole-5-carbonyl chloride, benzotriazole-5-carbonyl bromide, and benzotriazole-5-carbonyl iodide, preferably benzotriazole-5-carboxylic acid.

[0030] According to the present invention, the molar ratio between the compound represented by formula (α) and the peroxide and the compound represented by formula (β) is preferably 1:0.5-10:0.5-10, more preferably 1:1-5:1-5.

[0031] According to the present invention, the reaction temperature in step (1) is preferably 50-100 °C, more preferably 60-90 °C; the reaction temperature in step (2) is preferably 50-150 °C, more preferably 70-100 °C; the reaction temperature in step (3) is preferably 50-200 °C, more preferably 70-160 °C.

[0032] According to the present invention, the reaction time for steps (1), (2), and (3) is generally longer, the better. Generally speaking, the reaction time in step (1) is preferably 1-10 h, more preferably 3-5 h; the reaction time in step (2) is preferably 0.5-10 h, more preferably 1-3 h; the reaction time in step (3) is preferably 1-10 h, more preferably 3-6 h.

[0033] According to the present invention, a catalyst may be added in step (1). The catalyst is preferably an acidic catalyst, and for example, one or more of concentrated sulfuric acid, zinc chloride, aluminum trichloride, benzenesulfonic acid, and titanate may be selected. The addition amount of the catalyst is preferably 0.01%-3% of the compound represented by formula (α). After the reaction in step (1) is completed, the catalyst may be removed by alkali washing and / or water washing.

[0034] According to the present invention, a catalyst may be added in step (2). The catalyst may be an acidic catalyst or a basic catalyst, and for example, one of concentrated sulfuric acid, concentrated hydrochloric acid, concentrated nitric acid, sodium hydroxide, and potassium hydroxide may be selected, preferably concentrated sulfuric acid. The addition amount of the catalyst is preferably 0.5%-10% of the sum of the masses of the compound represented by formula (α) and the peroxide in step (1). After the reaction in step (2) is completed, the catalyst may be removed by alkali washing (when an acidic catalyst is used), acid washing (when a basic catalyst is used), and water washing.

[0035] According to the present invention, a catalyst may be added in step (3). The catalyst is preferably an acidic catalyst, and for example, one or more of concentrated sulfuric acid, zinc chloride, aluminum trichloride, benzenesulfonic acid, and titanate may be selected. The addition amount of the catalyst is preferably 0.5%-10% of the compound represented by formula (α). After the reaction in step (3) is completed, the catalyst may be removed by alkali washing and / or water washing.

[0036] According to the present invention, the reaction steps (1), (2), and (3) can be carried out in the presence of a diluent and / or a solvent, or without using a diluent and / or a solvent.

[0037] According to the present invention, the diluent can be selected from one or more of API Group I, II, III, IV, and V base oils. Common commercial products or grades include 150SN, 200SN, 350SN, 500SN, 650SN, 150BS, HVI-100, HVI-150, HVI-200, HVI-350, HVI-400, HVI-500, HVI-150BS, PAO4, PAO6, PAO8, PAO10, alkylbenzene, alkylnaphthalene, etc.

[0038] According to the present invention, the solvent can be selected from water, C 6-20 aromatics (such as benzene, toluene, xylene, and cumene), C 6-10 alkanes (such as n-hexane, cyclohexane, and petroleum ether), solvent naphtha, acetone, dimethylformamide, or one or more of them. These solvents can be used alone or in combination of two or more. The solvent can be removed by methods well known to those skilled in the art, such as under normal pressure or reduced pressure, after the reaction.

[0039] According to a particular embodiment of the present invention, the diluent and / or solvent can be added in a conventional amount in the art at any stage of the reaction step, without particular limitation.

[0040] According to the present invention, the steps (1), (2), and (3) can be carried out under the protection of an inert gas atmosphere. As the inert gas, for example, nitrogen, argon, etc. can be cited, without particular limitation.

[0041] According to the present invention, through the foregoing preparation method, as reaction products, a single compound can be produced, or a mixture composed of multiple compounds can be produced, or a mixture composed of one or more compounds and the foregoing diluent (if used) can be produced. These reaction products are all expected by the present invention, and the difference in their existing forms does not affect the realization of the effects of the present invention. Therefore, in the context of this specification, these reaction products are collectively referred to as benzotriazole derivatives without distinction. In view of this, according to the present invention, there is no absolute necessity to further purify the reaction products or further isolate a specific structure of benzotriazole derivative from the reaction products. Of course, this purification or separation is preferred for further enhancing the expected effects of the present invention, but it is not essential for the present invention. Nevertheless, as the purification or separation method, for example, methods such as purifying or separating the reaction products by column chromatography method or preparative chromatography can be cited.

[0042] The preparation method of the benzotriazole derivative of the present invention has simple steps and high conversion rate in the reaction process.

[0043] According to the present invention, the antioxidant is selected from one or more of phenolic ester type, thiophenol type, hindered phenol type and hindered amine type antioxidants. For example, for phenolic ester type antioxidants, hydroxy phenyl carboxylic esters with a molecular weight of 200-500 can be selected, and common commercial products include T512, IRGANOX L-135, etc. For thiophenol type antioxidants, T535, L115, L118, etc. can be selected. For hindered phenol type antioxidants, one or more of 2,6-di-tert-butyl-α-dimethylamino-p-cresol, 2,6-di-tert-butyl-p-cresol, 4,4-methylenebis(2,6-di-tert-butylphenol) and 2,6-di-tert-butyl-4-alkoxyphenol can be selected, and common commercial brands include T501. For hindered amine type antioxidants, one or more of alkylated aniline, alkylated diphenylamine and phenyl-α-naphthylamine can be selected, and common commercial products include IRGANOX L-01, IRGANOX L-57, T534, etc. The antioxidant is preferably a phenolic ester type antioxidant.

[0044] According to the present invention, the extreme pressure and anti-wear agent is selected from one or more of phosphate esters, phosphite esters, amine salts of phosphate esters, nitrogen-containing derivatives of thiophosphoric acid and amine salts of thiophosphates. For example, one or more of dibutyl acid phosphite, nitrogen-containing derivatives of thiophosphoric acid, tricresyl phosphate, amine salts of thiophosphates and amine salts of acid phosphate esters can be selected, and common commercial brands include T304, T305, T306, T307, T308, etc. The extreme pressure and anti-wear agent is preferably a phosphite ester.

[0045] According to the present invention, the rust inhibitor is selected from one or more of petroleum sulfonates, alkylbenzene sulfonates, imidazoline alkenyl succinates, alkenyl succinate esters, and zinc naphthenate. For example, barium petroleum sulfonate, sodium petroleum sulfonate, sodium alkylbenzene sulfonate, 17-alkenyl imidazoline alkenyl succinate, zinc naphthenate, and alkenyl succinate ester can be selected, and common commercial brand names include T701, T702, T703, T704, T706, T746, etc. The rust inhibitor is preferably a petroleum sulfonate.

[0046] According to the present invention, the lubricating oil base oil can be selected from one or more of API I, II, III, IV, and V types of lubricating oil base oils, such as mineral lubricating oil and / or synthetic lubricating oil. Common commercial brand names of the mineral lubricating oil include 100SN, 150SN, 600SN of type I, 100N, 150N, 150BS of type II, etc. Common commercial brand names of the synthetic lubricating oil include PAO4, PAO6, PAO8, PAO10, etc. The lubricating oil base oil is preferably a lubricating oil base oil with a viscosity index greater than 80, a saturated hydrocarbon mass fraction greater than 90%, and a sulfur content mass fraction less than 0.03%. The mineral lubricating oil can be a mixture of API type I lubricating oil base oil and API type II lubricating oil base oil, and the mass ratio between the two can be 1:0.5 - 5.

[0047] According to the present invention, the benzotriazole derivative accounts for 0.01% - 5% of the total mass of the gear oil composition, preferably 0.02% - 1%, more preferably 0.03% - 0.5%; the antioxidant accounts for 0.02% - 5% of the total mass of the gear oil composition, preferably 0.04% - 3%, more preferably 0.05% - 2%; the extreme pressure and anti-wear agent accounts for 0.01% - 10% of the total mass of the gear oil composition, preferably 0.05% - 8%, more preferably 1% - 5%; the rust inhibitor accounts for 0.01% - 10% of the total mass of the gear oil composition, preferably 0.05% - 5%, more preferably 0.1% - 3%; the lubricating oil base oil constitutes the main component of the gear oil composition.

[0048] The preparation method of the gear oil composition of the present invention includes the step of mixing each component in proportion.

[0049] The gear oil composition of the present invention has excellent antioxidant performance, anti-corrosion performance, and rust prevention performance, and can meet the requirements of GL-5 and above extreme pressure heavy-duty gear oil products. Detailed implementation manners

[0050] The following further illustrates the present invention through examples, but does not constitute a limitation to the present invention.

[0051] Unless otherwise specified, in the context of the present invention, the percentages mentioned are all mass percentages.

[0052] The sources of the main raw materials used are as follows:

[0053] Cardanol, Shanghai Wujing Chemical Technology Co., Ltd., industrial grade

[0054] Zinc chloride, Sinopharm Chemical Reagent Co., Ltd., analytical pure

[0055] Concentrated sulfuric acid, Sinopharm Chemical Reagent Co., Ltd., analytical pure

[0056] Hydrogen peroxide (30%), Sinopharm Chemical Reagent Co., Ltd., analytical pure

[0057] Formic acid, Sinopharm Chemical Reagent Co., Ltd., analytical pure

[0058] Benzotriazole-5-carboxylic acid, Sinopharm Chemical Reagent Co., Ltd., chemical pure

[0059] tert-Butyl chloride, Sinopharm Chemical Reagent Co., Ltd., analytical pure

[0060] Antioxidant T512, Xingpu Company of Sinopec Research Institute of Petroleum Processing, industrial grade

[0061] Metal deactivator T551, Xingpu Company of Sinopec Research Institute of Petroleum Processing, industrial grade

[0062] Toluene, Sinopharm Chemical Reagent Co., Ltd., analytical pure

[0063] Dimethylformamide, Sinopharm Chemical Reagent Co., Ltd., analytical pure

[0064] Diisooctyl sebacate, Chongqing Branch of Sinopec Lubricant Company, industrial grade

[0065] Extreme pressure and anti-wear agent T304, produced by Shandong Zibo Huihua Chemical Co., Ltd., industrial grade

[0066] Rust inhibitor T701, Jinzhou Donggong Petrochemical Products Co., Ltd., industrial grade

[0067] Base oil 100SN, base oil 150BS, Shanghai Petrochemical, industrial grade

[0068] Preparation of tert-butylated cardanol in Example 1

[0069] Take 100 g of cardanol, 8 g of formic acid, 0.3 g of sulfuric acid, and 200 g of hydrogen peroxide, add them into a three-necked flask equipped with mechanical stirring, a reflux condenser and temperature control, turn on the stirring and heating. Maintain the reaction temperature at 70 °C and react for 3 hours. After the reaction is completed, cool down to obtain a brownish-red transparent liquid. Filter the reaction product and wash it with 5% KOH solution for alkali washing, then wash it with distilled water until neutral. Distill the organic phase under reduced pressure at 100 Pa and 150 °C for 1 h to remove water and unreacted raw materials, and obtain an orange-red transparent liquid, epoxidized cardanol.

[0070] Dissolve 35 g of epoxidized cardanol in 100 ml of acetone, put it into a 250 ml three-necked reaction flask after dissolving, add 0.9 g of zinc chloride catalyst, turn on the stirring and heating. Maintain the reaction temperature at 60 °C, slowly drop 9.5 g of tert-butyl chloride into the reaction flask, and continue to react for 3 hours after the dropping is completed. After the reaction is completed, cool down to obtain a brownish-red transparent liquid. Filter the reaction product and wash it with 5% KOH solution for alkali washing, then wash it with distilled water until neutral. Distill it under reduced pressure at 1000 Pa and 120 °C for 1 h to remove the solvent, water and unreacted raw materials, and obtain a brownish-red viscous liquid, tert-butylated epoxidized cardanol.

[0071] The example reaction formula of the above reaction is shown as follows.

[0072]

[0073] Example 2

[0074] Add 20 g of the tert-butylated epoxidized cardanol prepared in Example 1, 0.2 g of concentrated sulfuric acid, 10 g of water, and 10 g of toluene into a three-necked flask equipped with mechanical stirring and a reflux condenser, stir and heat, and react at 85 °C for 1 h. After the reaction is completed, dissolve 12 g of benzotriazole-5-carboxylic acid in 80 g of dimethylformamide (DMF), drop it into the flask, and continue to reflux and react for 5 h after the dropping is completed, then stop the reaction. Wash the product 3 times with water and evaporate the solvent to obtain the benzotriazole derivative W-01 of the present invention, and the conversion rate is 91.3%.

[0075] The example reaction formula of the above reaction is shown as follows.

[0076]

[0077] Perform infrared spectroscopy and nuclear magnetic resonance hydrogen spectrum tests on the product W-01 prepared in Example 2. The analysis results of the infrared spectrum are shown in Table 1, and the analysis results of the nuclear magnetic resonance hydrogen spectrum are shown in Table 2.

[0078] Table 1 Infrared analysis results of product W-01

[0079]

[0080] As can be seen from Table 1, characteristic peaks such as the OH stretching vibration peak, the ester carbonyl C=O stretching vibration peak, the benzene ring skeletal stretching vibration peak, the C-N stretching vibration peak, and the NH bending vibration peak exist in the product W-01, indicating that the synthesized product is the target compound.

[0081] Table 2 Analysis Results of the 1H NMR Spectrum of Product W-01

[0082]

[0083] As can be seen from Table 2, it can be confirmed that the synthesized product is the target compound according to the attribution of each H element therein.

[0084] Example 3

[0085] Add 10 g of the tert-butylated epoxy cardanol prepared in Example 1, 0.2 g of concentrated sulfuric acid, 10 g of water, and 10 g of toluene to a three-necked flask equipped with a mechanical stirrer and a reflux condenser, stir, heat, and react at 95 °C for 1 h. After the reaction is completed, dissolve 12 g of benzotriazole-5-carboxylic acid in 80 g of dimethylformamide (DMF), add it dropwise to the flask, and continue refluxing for 3 h after the addition is complete, then stop the reaction. Wash the product 3 times with water, evaporate the solvent, and obtain the benzotriazole derivative W-02 of the present invention, with a conversion rate of 90.4%.

[0086] Example 4

[0087] Add 20 g of the tert-butylated epoxy cardanol prepared in Example 1, 0.2 g of concentrated sulfuric acid, 10 g of water, and 100 g of toluene to a three-necked flask equipped with a mechanical stirrer and a reflux condenser, stir, heat, and react at 110 °C for 1 h. After the reaction is completed, dissolve 50 g of benzotriazole-5-carboxylic acid in 120 g of dimethylformamide (DMF), add it dropwise to the flask, and continue refluxing for 6 h after the addition is complete, then stop the reaction. Wash the product 3 times with water, evaporate the solvent, and obtain the benzotriazole derivative W-03 of the present invention, with a conversion rate of 91.6%.

[0088] Examples 5-10 and Comparative Examples 1-4 of the Gear Oil Composition

[0089] The formulation compositions of Examples 5-10 and Comparative Examples 1-4 of the gear oil composition are shown in Table 3. Add each component in proportion to a blending container, and heat and stir at 60 °C for 2 hours to obtain the examples and comparative examples of the gear oil composition.

[0090] Corrosion stability tests were respectively carried out on the gear oil compositions of Examples 5-7 and Comparative Examples 1-3 according to the ASTM D130 copper strip corrosion test method. The test conditions were 121 °C and 3 h. After the test was completed, take out the copper strip and measure the copper dissolution amount. The test results are shown in Table 4.

[0091] The antioxidant performance tests of the gear oil compositions of Examples 5 to 7 and Comparative Examples 1 to 3 were carried out using a DSC instrument of model HP DSC 2+ from Mettler Toledo. The test temperature was 175 °C, the oxygen pressure was 3.5 MPa, and the heating rate was 10 °C / min. The test results are shown in Table 4.

[0092] Table 3

[0093]

[0094] Table 4

[0095]

[0096] The rust performance tests of the gear oil compositions of Examples 5 to 10 and Comparative Examples 2 and 4 were carried out using a rust tester (GB / T 11143 rust prevention performance tester produced by Dalian Intelligent Instrument Co., Ltd.). The test conditions were: artificial seawater, test temperature 60 °C, and test time 24 h. The test results are shown in Table 5.

[0097] Table 5

[0098]

[0099] As can be seen from Tables 3 to 5, the gear oil composition of the present invention has excellent antioxidant performance, corrosion resistance, and rust prevention performance.

Claims

1. A gear oil composition comprising a benzotriazole derivative, an antioxidant, an extreme pressure and antiwear agent, a rust inhibitor and a lubricating oil base oil, wherein the structure of the benzotriazole derivative is shown in formula (I): In formula (I), n is an integer between 1 and 10; the R1 group is selected from C 1-20 a linear or branched alkylene group; the R2 groups in the n repeating units are the same as or different from each other, and are each independently selected from C 1-20 a linear or branched alkylene group; the R3 group is selected from H and C 1-20 a linear or branched alkyl group; the A groups in the n repeating units are the same as or different from each other, and are each independently selected from the group shown in formula (II) and the group shown in formula (III); In formula (II) and formula (III), * represents the bonding end bonded to formula (I); The R4 group and the R5 group are each independently selected from H and C 1-10 a straight-chain or branched-chain alkyl group.

2. The gear oil composition according to claim 1, characterized in that, In formula (I), n is an integer between 1 and 5, and the R1 group is selected from C 1-10 a linear or branched alkylene group, and the R2 groups in n repeating units are each independently selected from C 1-10 a linear or branched alkylene group, the R3 group is selected from H and C 1-10 a linear or branched alkyl group, and the R4 group and the R5 group are each independently selected from C 1-4 a linear or branched alkyl group.

3. The gear oil composition according to claim 1, characterized in that, In formula (I), n is an integer between 1 and 3, and the R1 group is selected from C 1-8 a linear or branched alkylene group, and the R2 groups in n repeating units are each independently selected from C 1-8 a linear or branched alkylene group, the R3 group is selected from H and C 1-8 a linear or branched alkyl group, the R4 group and the R5 group are selected from tert-butyl or the R4 group is selected from tert-butyl and the R5 group is selected from H.

4. The gear oil composition according to claim 1, characterized in that, The benzotriazole derivative comprises one or more of the following structural compounds:

5. The gear oil composition according to claim 1, characterized in that, The preparation method of the benzotriazole derivative comprises the following steps: (1) Reacting the compound shown in formula (α) with a peroxide; In formula (α), n is an integer between 1 and 10; the R1 group is selected from C 1-20 a linear or branched alkylene group; the R2 groups in the n repeating units are the same as or different from each other and are each independently selected from C 1-20 a linear or branched alkylene group; the R3 group is selected from H and C 1-20 a linear or branched alkyl group; the A" groups in the n repeating units are selected from -CH=CH-; the R4 group and the R5 group are each independently selected from H and C 1-10 a linear or branched alkyl group; (2) Subjecting the reaction product of step (1) to a hydrolysis reaction; (3) Reacting the hydrolysis reaction product of step (2) with the compound shown in formula (β), and collecting the product; Wherein the X group is selected from OH, F, Cl, Br, I.

6. The gear oil composition according to claim 5, characterized in that, In formula (α), n is an integer between 1 and 5, and the R1 group is selected from C 1-10 a linear or branched alkylene group, and the R2 groups in the n repeating units are each independently selected from C 1-10 a linear or branched alkylene group, the R3 group is selected from H and C 1-10 a linear or branched alkyl group, and the R4 group and the R5 group are each independently selected from C 1-4 a linear or branched alkyl group.

7. The gear oil composition according to claim 5, characterized in that, In formula (α), n is an integer between 1 and 3, and the R1 group is selected from C 1-8 a linear or branched alkylene group, and the R2 groups in the n repeating units are each independently selected from C 1-8 a linear or branched alkylene group, the R3 group is selected from H and C 1-8 a linear or branched alkyl group, the R4 group and the R5 group are selected from tert-butyl or the R4 group is selected from tert-butyl and the R5 group is selected from H.

8. The gear oil composition according to claim 5, characterized in that, The compound shown in formula (α) is selected from cardanol, alkylated cardanol; the peroxide is selected from one or more of hydrogen peroxide, performic acid, peracetic acid, peroxysulfonic acid, m-chloroperbenzoic acid, tert-butyl hydroperoxide, tert-butyl peracetate, methyl ethyl ketone peroxide, benzoyl peroxide and cyclohexanone peroxide; the compound shown in formula (β) is selected from one or more of benzotriazole-5-carboxylic acid, benzotriazole-5-carbonyl fluoride, benzotriazole-5-carbonyl chloride, benzotriazole-5-carbonyl bromide and benzotriazole-5-carbonyl iodide.

9. The gear oil composition according to claim 5, characterized in that, The molar ratio between the compound shown in formula (α), the peroxide and the compound shown in formula (β) is 1:0.5 - 10:0.5 - 10; the reaction temperature of step (1) is 50 - 100 °C; the reaction temperature of step (2) is 50 - 150 °C; the reaction temperature of step (3) is 50 - 200 °C.

10. The gear oil composition according to any one of claims 1 to 9, characterized in that, The antioxidant is selected from one or more of phenolic ester type, thiophenol type, hindered phenol type and hindered amine type antioxidants; the extreme pressure and antiwear agent is selected from one or more of phosphate esters, phosphite esters, amine salts of phosphate esters, nitrogen-containing derivatives of thiophosphoric acid and amine salts of thiophosphoric acid; the rust inhibitor is selected from one or more of petroleum sulfonates, alkylbenzene sulfonates, imidazoline alkenyl succinates, alkenyl succinates and zinc naphthenate; the lubricating oil base oil is selected from one or more of API Group I, II, III, IV, V lubricating oil base oils.

11. The gear oil composition according to any one of claims 1 to 9, characterized in that, The benzotriazole derivative accounts for 0.01% - 5% of the total mass of the gear oil composition; the antioxidant accounts for 0.02% - 5% of the total mass of the gear oil composition; the extreme pressure and antiwear agent accounts for 0.01% - 10% of the total mass of the gear oil composition; the rust inhibitor accounts for 0.01% - 10% of the total mass of the gear oil composition; the lubricating oil base oil constitutes the main component of the gear oil composition.

12. The preparation method of the gear oil composition according to any one of claims 1 - 11, comprising the step of mixing each component therein in proportion.

Images