Antioxidant lubricating oil composition and preparation method thereof

Abstract

The invention relates to the technical field of lubricating oil, in particular to an antioxidant lubricating oil composition and a preparation method thereof.The antioxidant lubricating oil composition is prepared from, by weight, 75-80 parts of paraffin base oil, 2.5-3 parts of antioxidant lubricating filler, 3-4 parts of active additive, 1.8-2 parts of viscosity improver, 0.8-1 part of pour point depressant, 0.08-0.1 part of defoaming agent and 0.8-1 part of antirust agent; the phosphate antioxidant is grafted on the filler in a covalent binding manner, compounded with the borate active additive and added into the base oil, so that the oxidation resistance of the lubricating oil is greatly improved, and the lubricating oil can exert better, longer and more stable high-temperature-resistant lubricating performance due to the introduction of the active additive.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lubricating oil, in particular to an antioxidant lubricating oil composition and a preparation method thereof. BACKGROUND

[0002] It is well known that one of the core roles of lubricating oil is to reduce friction and wear between mechanical parts. Reducing friction directly means improving mechanical efficiency, thereby reducing energy consumption. Reducing energy loss through the use of lubricating oil directly corresponds to less greenhouse gas (especially carbon dioxide) emissions, achieving low carbon emission effect.

[0003] Research has found that paraffin-based base oil accounts for the majority of the market share of lubricating oil due to its excellent viscosity-temperature performance, low cost and wide source. However, due to its molecular structure containing a large number of alkane chains, it is easy to undergo oxidative chain reaction under high temperature, oxygen and metal ion catalysis, resulting in changes in viscosity, blocking of oil paths, and accumulation of acidic substances, accelerating corrosion of metal parts, and thus producing deposits and wearing out equipment. For example, patent CN116042287B "Wear-resistant antioxidant lubricating oil and preparation method and application thereof" records the following technical solution: by adding a phosphorus-containing anti-wear agent, the antioxidant property of the lubricating oil is improved. However, researchers have further found that in order to improve the performance of the lubricating oil, various fillers are usually added to improve its lubricating performance, but the phosphoric acid ester antioxidant agent is difficult to cooperate with the fillers, and is prone to aggregation, thereby causing oxidation and reducing its performance. Therefore, a lubricating oil composition with excellent antioxidant property is needed. SUMMARY

[0004] The purpose of the present application is to provide an antioxidant lubricating oil composition and a preparation method thereof, which grafts a phosphoric acid ester antioxidant agent onto a filler in a covalent bonding manner, and is compounded with a boric acid ester active additive and added to a base oil, thereby greatly improving the antioxidant property of the lubricating oil, and the introduction of the active additive enables it to exhibit better and more long-term stable high-temperature lubrication performance.

[0005] The purpose of the present application can be achieved by the following technical solution: a preparation method of an antioxidant lubricating oil composition, comprising the following steps: weighing the following raw materials: 75-80 parts of paraffin base oil, 2.5-3 parts of antioxidant lubricating filler, 3-4 parts of active additive, 1.8-2 parts of viscosity improver, 0.8-1 part of pour point depressant, 0.08-0.1 part of defoaming agent and 0.8-1 part of anti-rust agent; mixing the paraffin base oil, the antioxidant lubricating filler, the active additive, the viscosity improver, the pour point depressant, the defoaming agent and the anti-rust agent, and ultrasonic dispersing for 15-20 min to prepare an antioxidant lubricating oil composition; The paraffin base oil is from Qingyang, and the specification is 150SN; The viscosity modifier is Viscotech 533; The pour point depressant is from Sanyo Chemical, and the specification is Aclube P-2100; The defoaming agent is from Wincrete, and the specification is Antifoam 793; The rust inhibitor is from Poly-Fan, and the specification is TS-6.

[0006] The active additive is prepared by the following steps: Step A1: 3, 5-di-tert-butyl-2-hydroxybenzaldehyde, N-phenyl-p-phenylenediamine and ethanol are mixed, and under the conditions of nitrogen protection, a stirring rate of 120-140 rpm and a temperature of 70°C, reaction is carried out for 2-3 h to prepare an intermediate; Step A2: benzotriazole, formaldehyde solution and deionized water are mixed, and under the conditions of a stirring rate of 120-140 rpm and a temperature of 80°C, reaction is carried out for 30-40 min, rotary evaporation is carried out, filtration is carried out, and a filter cake is obtained, the filter cake, boric acid and toluene are mixed, and under the conditions of a stirring rate of 120-140 rpm and a temperature of 110°C, reaction is carried out for 1.5-2 h, the intermediate is further added, the temperature is raised to 115°C, and reaction is continued for 2-3 h, filtration is carried out after vacuum distillation, and washing is carried out to prepare the active additive; Further, in step A1: the amount ratio of 3, 5-di-tert-butyl-2-hydroxybenzaldehyde, N-phenyl-p-phenylenediamine and ethanol is 2.3-2.4 g: 1.85-1.9 g: 40-45 mL; Further, in step A2: the amount ratio of benzotriazole, formaldehyde solution, deionized water, boric acid, toluene and the intermediate is 2.4-2.42 g: 45-50 mL: 15-20 mL: 0.61-0.62 g: 35-40 mL: 4.2-4.3 g, and the mass fraction of the formaldehyde solution is 36%.

[0007] Further, in the reaction process, the aldehyde group in 3, 5-di-tert-butyl-2-hydroxybenzaldehyde reacts with the primary amine group in N-phenyl-p-phenylenediamine to form a Schiff base structure to prepare the intermediate, benzotriazole reacts with formaldehyde to form an intermediate product with a hydroxyl group, the intermediate product reacts with boric acid to form a borate ester structure, the intermediate product is further added to the intermediate to react with the phenolic hydroxyl group in the intermediate to form an active additive containing boron-nitrogen coordination and a Schiff base structure.

[0008]

[0009] The antioxidant lubricating filler is prepared by the following steps: Step B1: graphene oxide, phosphomolybdic acid and deionized water were mixed and ultrasonic dispersed for 30-35 min, stirring at a stirring rate of 300-400 rpm and a temperature of room temperature, cetyltrimethylammonium bromide was added and stirred for 15-20 min, L-cysteine solution was added and ultrasonic dispersed for 10-15 min, it was transferred to a reaction kettle and reacted for 24 h at a temperature of 180℃, filtered, washed, dried, transferred to a tube furnace, heated to 750℃ at a rate of 5℃ / min under nitrogen protection, kept for 2 h, ground, and the precursor 1 was prepared; Step B2: precursor 1 and hydrogen peroxide solution were mixed and ultrasonic dispersed for 15-20 min, stood for 12 h, filtered, dried, and the precursor 2 was prepared, the precursor 2, deionized water and ethanol were mixed and ultrasonic dispersed for 40-50 min, stirring at a stirring rate of 120-180 rpm and a temperature of room temperature, iron dichloride tetrahydrate and iron chloride trihydrate hexahydrate were added and stirred for 15-20 min, heated to 80℃, ammonia water was added and reacted for 30-40 min, centrifugal filtration, washed, dried, and the precursor 3 was prepared; Step B3: the precursor 3 and isopropanol were mixed and ultrasonic dispersed for 15-20 min, stirring at a stirring rate of 120-180 rpm and a temperature of 60℃, O,O-diisooctyl phosphorodithioate was added and reacted for 24 h, centrifugal filtration, washed, dried, and the antioxidant lubricating filler was prepared.

[0010] Further, in step B1: the amount ratio of graphene oxide, phosphomolybdic acid, deionized water, cetyltrimethylammonium bromide and L-cysteine solution was 0.04-0.05 g:0.46-0.48 g:20-25 mL:0.008-0.01 g:8-10 mL, and the mass concentration of L-cysteine solution was 0.08 g / mL; The graphene oxide was from Pioneer Nano, with a product code of XFSG01; Further, in step B2: the amount ratio of precursor 1 and hydrogen peroxide solution was 0.45-0.5 g:30-35 mL, the molar concentration of hydrogen peroxide solution was 5 mol / L, and the amount ratio of precursor 2, deionized water, ethanol, iron dichloride tetrahydrate, iron chloride trihydrate hexahydrate and ammonia water was 0.1-0.12 g:50-60 mL:50-60 mL:0.14-0.15 g:0.36-0.37 g:20-25 mL, and the mass fraction of ammonia water was 15%; Further, in step B3: the amount ratio of precursor 3, isopropanol and O,O-diisooctyl phosphorodithioate was 0.14-0.16 g:80-100 mL:25-30 mL.

[0011] Further, in the reaction process, phosphomolybdic acid is used as a molybdenum source, L-cysteine solution is used as a sulfur source and a reducing agent, cetyltrimethylammonium bromide is used as a dopant and a surfactant, a hydrothermal method is adopted to load molybdenum disulfide on a graphene oxide substrate, a precursor 1 is prepared by calcination, the precursor 1 is soaked in a hydrogen peroxide solution, due to the doping of cetyltrimethylammonium bromide in the preparation process of molybdenum disulfide, defects appear in the molybdenum disulfide, and at the same time, the etching of the hydrogen peroxide solution makes the surface appear sulfur atom vacancies, a precursor 2 is prepared, a hydrothermal method is adopted to load ferroferric oxide on the surface of the precursor 2 by using ferrous chloride tetrahydrate and ferric chloride hexahydrate as an iron source, a precursor 3 is prepared, and the reaction between the sulfur atom vacancy defects and the mercapto group in O,O-diisooctyl dithiophosphate hydrogen is grafted on the precursor 3 to prepare an antioxidant lubricating filler.

[0012] The application discloses an antioxidant lubricating oil composition and a preparation method thereof.

[0013] The antioxidant lubricating filler is prepared by using graphene oxide as a substrate, loading molybdenum disulfide with defect sites, in-situ generating magnetic ferroferric oxide particles, and in-situ grafting an antioxidant agent through the defect sites. The introduction of the magnetic ferroferric oxide particles greatly improves the loading capacity of the filler. Due to the synthesis method, the magnetic ferroferric oxide particles can be uniformly distributed on the substrate and can reduce friction. Due to the magnetism of the magnetic ferroferric oxide particles, the filler can be more effectively adsorbed on the metal contact surface, which is stable and beneficial to lubrication. The special structure of the magnetic ferroferric oxide particles can change the friction mode, thereby further reducing the friction loss. After the covalent grafting of the phosphate antioxidant, the phosphate antioxidant is firmly fixed on the substrate and is compounded with the borate active additive. Due to the boron-nitrogen coordination and Schiff base structure of the active additive, the active additive can effectively play a synergistic effect after being compounded, thereby greatly improving the antioxidant performance of the lubricating oil. The active additive itself can also play a certain anti-wear performance, which further improves the lubricating effect of the lubricating oil. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0015] Embodiment 1: A preparation method of an antioxidant lubricating oil composition, comprising the following steps: weighing raw materials in the following weight parts: 75 parts of paraffin base oil, 2.5 parts of antioxidant lubricating filler, 3 parts of active additive, 1.8 parts of viscosity modifier, 0.8 parts of pour point depressant, 0.08 parts of defoaming agent and 0.8 parts of rust inhibitor; mixing the paraffin base oil, the antioxidant lubricating filler, the active additive, the viscosity modifier, the pour point depressant, the defoaming agent and the rust inhibitor, and ultrasonic dispersion for 15 min to prepare an antioxidant lubricating oil composition; The paraffin base oil is from Qingyang, and the specification is 150SN; The viscosity modifier is Viscotech 533; The pour point depressant is from Sanyo Chemical, and the specification is Aclube P-2100; The defoaming agent is from Wincrete, and the specification is Antifoam 793; The rust inhibitor is from Poly-Fan, and the specification is TS-6.

[0016] The active additive is prepared by the following steps: Step A1: mixing 3,5-di-tert-butyl-2-hydroxybenzaldehyde, N-phenyl-p-phenylenediamine and ethanol, and reacting for 2 h under the conditions of nitrogen protection, a stirring speed of 120 rpm and a temperature of 70 ℃ to prepare an intermediate; Step A2: mixing benzotriazole, formaldehyde solution and deionized water, and reacting for 30 min under the conditions of a stirring speed of 120 rpm and a temperature of 80 ℃, rotary evaporation, filtration to obtain a filter cake, mixing the filter cake, boric acid and toluene, and reacting for 1.5 h under the conditions of a stirring speed of 120 rpm and a temperature of 110 ℃, then adding the intermediate, heating to 115 ℃, and continuing to react for 2 h, filtration, washing and pressure reduction distillation to prepare the active additive; Further, in step A1: the amount ratio of 3,5-di-tert-butyl-2-hydroxybenzaldehyde, N-phenyl-p-phenylenediamine and ethanol is 2.3 g:1.85 g:40 mL; Further, in step A2: the amount ratio of benzotriazole, formaldehyde solution, deionized water, boric acid, toluene and the intermediate is 2.4 g:45 mL:15 mL:0.6 g:35 mL:4.2 g, and the mass fraction of the formaldehyde solution is 36%.

[0017] The antioxidant lubricating filler is prepared by the following steps: Step B1: Mix graphene oxide, phosphomolybdic acid and deionized water, and ultrasonic dispersion for 35 min, stir at a stirring rate of 300 rpm and room temperature, and then add cetyltrimethylammonium bromide and stir for 15 min, and then add L-cysteine solution and ultrasonic dispersion for 15 min, and then transfer to a reaction kettle and react for 24 h at a temperature of 180℃, filter, wash, dry, and then transfer to a tube furnace and heat to 750℃ at a rate of 5℃ / min under nitrogen protection, and then keep for 2 h, grind, and then obtain precursor 1; Step B2: Mix precursor 1 and hydrogen peroxide solution, and ultrasonic dispersion for 15 min, and then stand for 12 h, filter, and dry to obtain precursor 2, and then mix precursor 2, deionized water and ethanol, and ultrasonic dispersion for 40 min, and then stir at a stirring rate of 180 rpm and room temperature, and then add ferric chloride tetrahydrate and ferric chloride hexahydrate and stir for 15 min, and then heat to 80℃, and then add ammonia water and react for 40 min, and then centrifugal filter, wash, and dry to obtain precursor 3; Step B3: Mix precursor 3 and isopropanol, and ultrasonic dispersion for 20 min, and then stir at a stirring rate of 120 rpm and a temperature of 60℃, and then add O,O-diisooctyl phosphorodithioate and react for 24 h, and then centrifugal filter, wash, and dry to obtain antioxidant lubricating filler.

[0018] Further, in step B1: the amount ratio of graphene oxide, phosphomolybdic acid, deionized water, cetyltrimethylammonium bromide and L-cysteine solution is 0.04 g:0.48 g:20 mL:0.008 g:10 mL, and the mass concentration of L-cysteine solution is 0.08 g / mL; The graphene oxide is from Pioneer Nanometer, and the item number is XFSG01; Further, in step B2: the amount ratio of precursor 1 and hydrogen peroxide solution is 0.5 g:30 mL, the molar concentration of hydrogen peroxide solution is 5 mol / L, and the amount ratio of precursor 2, deionized water, ethanol, ferric chloride tetrahydrate, ferric chloride hexahydrate and ammonia water is 0.12 g:50 mL:60 mL:0.15 g:0.37 g:20 mL, and the mass fraction of ammonia water is 15%; Further, in step B3: the amount ratio of precursor 3, isopropanol and O,O-diisooctyl phosphorodithioate is 0.14 g:100 mL:25 mL.

[0019] A method for preparing an antioxidant lubricating oil composition, comprising the following steps: weighing the following raw materials: 80 parts of paraffin base oil, 2.5 parts of antioxidant lubricating filler, 3 parts of active additive, 2 parts of viscosity modifier, 0.8 parts of pour point depressant, 0.1 parts of defoaming agent and 0.8 parts of anti-rust agent; mixing the paraffin base oil, antioxidant lubricating filler, active additive, viscosity modifier, pour point depressant, defoaming agent and anti-rust agent, and ultrasonic dispersion for 20 min to prepare an antioxidant lubricating oil composition; The paraffin base oil is from Qingyang, with a specification of 150SN; The viscosity modifier is Viscotech 533; The pour point depressant is from Sanyo Chemical, with a specification of Aclube P-2100; The defoaming agent is from Wincreate, with a specification of Antifoam 793; The anti-rust agent is from Poly-Fan Industry, with a specification of TS-6.

[0020] The active additive is prepared by the following steps: Step A1: mixing 3,5-di-tert-butyl-2-hydroxybenzaldehyde, N-phenyl-p-phenylenediamine and ethanol, under the conditions of nitrogen protection, stirring rate of 140 rpm and temperature of 70℃, reacting for 2 h to prepare an intermediate; Step A2: mixing benzotriazole, formaldehyde solution and deionized water, under the conditions of stirring rate of 140 rpm and temperature of 80℃, reacting for 30 min, rotary evaporation, filtration to obtain a filter cake, mixing the filter cake, boric acid and toluene, under the conditions of stirring rate of 140 rpm and temperature of 110℃, reacting for 2 h, then adding the intermediate, heating to 115℃, continuing to react for 2 h, vacuum distillation, filtration and washing to prepare the active additive; Further, in step A1: the amount ratio of 3,5-di-tert-butyl-2-hydroxybenzaldehyde, N-phenyl-p-phenylenediamine and ethanol is 2.4 g:1.9 g:40 mL; Further, in step A2: the amount ratio of benzotriazole, formaldehyde solution, deionized water, boric acid, toluene and intermediate is 2.42 g:45 mL:15 mL:0.62 g:35 mL:4.2 g, and the mass fraction of formaldehyde solution is 36%.

[0021] The antioxidant lubricating filler is prepared by the following steps: Step B1: graphene oxide, phosphomolybdic acid and deionized water were mixed and ultrasonically dispersed for 30 min, stirring at a stirring rate of 300 rpm and a temperature of room temperature, cetyltrimethylammonium bromide was added and stirred for 15 min, L-cysteine solution was added and ultrasonically dispersed for 10 min, it was transferred to a reaction kettle and reacted for 24 h at a temperature of 180℃, filtered, washed, dried, transferred to a tube furnace, heated to 750℃ at a rate of 5℃ / min under nitrogen protection, and kept for 2 h, ground, and the precursor 1 was prepared; Step B2: precursor 1 and hydrogen peroxide solution were mixed and ultrasonically dispersed for 15 min, stood for 12 h, filtered, dried, and precursor 2 was prepared, precursor 2, deionized water and ethanol were mixed and ultrasonically dispersed for 40 min, stirring at a stirring rate of 120 rpm and a temperature of room temperature, iron dichloride tetrahydrate and iron chloride trihydrate hexahydrate were added and stirred for 15 min, heated to 80℃, ammonia water was added and reacted for 30 min, centrifugal filtration, washing, drying, and precursor 3 was prepared; Step B3: precursor 3 and isopropanol were mixed and ultrasonically dispersed for 15 min, stirring at a stirring rate of 120 rpm and a temperature of 60℃, O,O-diisooctyl phosphorodithioate was added and reacted for 24 h, centrifugal filtration, washing, drying, and the antioxidant lubricating filler was prepared.

[0022] Further, in step B1: the amount ratio of graphene oxide, phosphomolybdic acid, deionized water, cetyltrimethylammonium bromide and L-cysteine solution was 0.04 g:0.46 g:20 mL:0.008 g:8 mL, and the mass concentration of L-cysteine solution was 0.08 g / mL; The graphene oxide was from Pioneer Nano, with a product number of XFSG01; Further, in step B2: the amount ratio of precursor 1 and hydrogen peroxide solution was 0.45 g:30 mL, the molar concentration of hydrogen peroxide solution was 5 mol / L, and the amount ratio of precursor 2, deionized water, ethanol, iron dichloride tetrahydrate, iron chloride trihydrate hexahydrate and ammonia water was 0.1 g:50 mL:50 mL:0.14 g:0.36 g:20 mL, and the mass fraction of ammonia water was 15%; Further, in step B3: the amount ratio of precursor 3, isopropanol and O,O-diisooctyl phosphorodithioate was 0.14 g:80 mL:25 mL.

[0023] A method for preparing an antioxidant lubricating oil composition, comprising the following steps: weighing the following raw materials: 80 parts of paraffin base oil, 3 parts of antioxidant lubricating filler, 4 parts of active additive, 2 parts of viscosity modifier, 1 part of pour point depressant, 0.1 part of defoaming agent and 1 part of anti-rust agent; mixing the paraffin base oil, antioxidant lubricating filler, active additive, viscosity modifier, pour point depressant, defoaming agent and anti-rust agent, and ultrasonic dispersion for 20 min to prepare an antioxidant lubricating oil composition; The paraffin base oil is from Qingyang, with a specification of 150SN; The viscosity modifier is Viscotech 533; The pour point depressant is from Sanyo Chemical, with a specification of Aclube P-2100; The defoaming agent is from Wincreate, with a specification of Antifoam 793; The anti-rust agent is from Poly-Fan Industry, with a specification of TS-6.

[0024] The active additive is prepared by the following steps: Step A1: mixing 3,5-di-tert-butyl-2-hydroxybenzaldehyde, N-phenyl-p-phenylenediamine and ethanol, under the conditions of nitrogen protection, stirring rate of 140 rpm and temperature of 70℃, reacting for 3h to prepare an intermediate; Step A2: mixing benzotriazole, formaldehyde solution and deionized water, under the conditions of stirring rate of 140 rpm and temperature of 80℃, reacting for 40 min, rotary evaporation, filtration to obtain a filter cake, mixing the filter cake, boric acid and toluene, under the conditions of stirring rate of 140 rpm and temperature of 110℃, reacting for 2h, then adding the intermediate, heating to 115℃, continuing to react for 3h, reducing pressure distillation, filtration and washing to prepare the active additive; Further, in step A1: the amount ratio of 3,5-di-tert-butyl-2-hydroxybenzaldehyde, N-phenyl-p-phenylenediamine and ethanol is 2.4g:1.9g:45mL; Further, in step A2: the amount ratio of benzotriazole, formaldehyde solution, deionized water, boric acid, toluene and intermediate is 2.42g:50mL:20mL:0.62g:40mL:4.3g, and the mass fraction of formaldehyde solution is 36%.

[0025] The antioxidant lubricating filler is prepared by the following steps: Step B1: graphene oxide, phosphomolybdic acid and deionized water were mixed and ultrasonic dispersed for 35 min, stirring at a stirring rate of 400 rpm and a temperature of room temperature, cetyltrimethylammonium bromide was added and stirred for 20 min, L-cysteine solution was added and ultrasonic dispersed for 15 min, it was transferred to a reaction kettle and reacted for 24 h at a temperature of 180℃, filtered, washed, dried, transferred to a tube furnace, heated to 750℃ at a rate of 5℃ / min under nitrogen protection, kept for 2 h, ground, and the precursor 1 was prepared; Step B2: precursor 1 and hydrogen peroxide solution were mixed and ultrasonic dispersed for 20 min, stood for 12 h, filtered, dried, and the precursor 2 was prepared, the precursor 2, deionized water and ethanol were mixed and ultrasonic dispersed for 50 min, stirring at a stirring rate of 180 rpm and a temperature of room temperature, iron dichloride tetrahydrate and iron trichloride hexahydrate were added and stirred for 20 min, heated to 80℃, ammonia water was added and reacted for 40 min, centrifugal filtration, washed, dried, and the precursor 3 was prepared; Step B3: the precursor 3 and isopropanol were mixed and ultrasonic dispersed for 20 min, stirring at a stirring rate of 180 rpm and a temperature of 60℃, O,O-diisooctyl phosphorodithioate was added and reacted for 24 h, centrifugal filtration, washed, dried, and the antioxidant lubricating filler was prepared.

[0026] Further, in step B1: the amount ratio of graphene oxide, phosphomolybdic acid, deionized water, cetyltrimethylammonium bromide and L-cysteine solution was 0.05 g:0.48 g:25 mL:0.01 g:10 mL, and the mass concentration of L-cysteine solution was 0.08 g / mL; The graphene oxide was from Pioneer Nano, with a product code of XFSG01; Further, in step B2: the amount ratio of precursor 1 and hydrogen peroxide solution was 0.5 g:35 mL, the molar concentration of hydrogen peroxide solution was 5 mol / L, and the amount ratio of precursor 2, deionized water, ethanol, iron dichloride tetrahydrate, iron trichloride hexahydrate and ammonia water was 0.12 g:60 mL:60 mL:0.15 g:0.37 g:25 mL, and the mass fraction of ammonia water was 15%; Further, in step B3: the amount ratio of precursor 3, isopropanol and O,O-diisooctyl phosphorodithioate was 0.16 g:100 mL:30 mL.

[0027] Comparative Example 1: Compared with Example 3, the antioxidant lubricating filler in the preparation process of the antioxidant lubricating oil composition of Example 3 was replaced by a combination of graphene oxide, molybdenum disulfide and phosphate antioxidant, and other steps were the same, wherein the weight ratio of graphene oxide, molybdenum disulfide and phosphate antioxidant was 0.2 g:0.1 g:5 mL; The graphene oxide is from Pioneer Nanotechnology with the model number XFSG01, the molybdenum disulfide is from Zhiheng Zhiyuan with the specification 500 mesh, and the phosphate antioxidant is from kemike with the model number T202.

[0028] Comparative Example 2: This comparative example is compared with Example 3. In the preparation process of the antioxidant lubricating oil composition of Example 3, the active additive is replaced by diethanolamine borate, and other steps are the same.

[0029] The antioxidant lubricating oil compositions prepared in Example 1, Example 2, Example 3, Comparative Example 1 and Comparative Example 2 are subjected to friction and wear experiments by using a reciprocating friction tester (HT-1000). The steel ball material is Gcr15, the diameter is 6 mm, the hardness is HRC61, the steel disc material is Gcr15, the thickness is 4 mm, the hardness is HRC61, the load is 8 N, the speed is 300 r / min, the rotation radius is 5 mm, the rotation linear speed is 9.42 m / min, and the experimental temperature is 30°C, 160°C and 250°C. The detection results are shown in Table 1 below: Table 1 Friction performance detection results

[0030] As can be seen from the table detection results, comparing Example 1, Example 2 and Example 3 with Comparative Example 1 and Comparative Example 2, in the preparation process of the antioxidant lubricating oil composition of Example 3, the antioxidant lubricating filler is replaced by the combination of graphene oxide, molybdenum disulfide and phosphate antioxidant. Due to the lack of special structure and covalent grafting of antioxidant, Comparative Example 1 cannot reduce friction and resistance well under high temperature conditions, and its wear rate increases rapidly. In Comparative Example 2, the active additive in the preparation process of the antioxidant lubricating oil composition of Example 3 is replaced by diethanolamine borate, which cannot play a good compounding effect with the antioxidant lubricating filler, resulting in a certain decline in the performance of Comparative Example 2.

[0031] The antioxidant lubricating oil compositions prepared in Example 1, Example 2, Example 3, Comparative Example 1 and Comparative Example 2 are subjected to antioxidant performance tests by using a high-pressure differential scanning calorimeter. The initial oxidation temperature and oxidation induction period are used as the judgment of the antioxidant performance. In the initial oxidation temperature test, the sample mass is 0.5 mg, the oxygen flow rate is 100 mL / min, the pressure is 3.5 MPa, the initial temperature is room temperature, and the heating rate is 10°C / min. In the oxidation induction period test, the sample mass is 1.0 mg, the flow rate is 100 mL / min, the initial temperature is room temperature, and the heating rate is 30°C / min. The detection results are shown in Table 2 below: Table 2 Mechanical property detection results

[0032] From the results of the table, it can be seen that comparing Example 1, Example 2 and Example 3 with Comparative Example 1 and Comparative Example 2, in Comparative Example 1, the antioxidant lubricating filler in the preparation process of the antioxidant lubricating oil composition of Example 3 is replaced by a combination of graphene oxide, molybdenum disulfide and phosphate antioxidant. Due to the lack of special structure and covalent grafting of the antioxidant, the initial oxidation temperature of Comparative Example 1 is significantly reduced, and the oxidation induction period is significantly shortened. In Comparative Example 2, the active additive in the preparation process of the antioxidant lubricating oil composition of Example 3 is replaced by diethanolamine borate. Compared with Example 3, the initial oxidation temperature of Comparative Example 2 is reduced, and the oxidation induction period is shortened, indicating that there is a good synergistic antioxidant effect between the active additive and the antioxidant lubricating filler.

[0033] In the description of the specification, the description of the terms "one embodiment", "example", "specific example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0034] The above is only an example and description of the concept of the present application, and those skilled in the art can make various modifications or supplements or use similar ways to replace the described specific embodiments, as long as they do not deviate from the concept of the present application, which shall belong to the protection scope of the present application.

Claims

1. A method for preparing an antioxidant lubricating oil composition, characterized in that: The process includes the following steps: Weigh the following raw materials by weight: 75-80 parts paraffinic base oil, 2.5-3 parts antioxidant lubricating filler, 3-4 parts active additive, 1.8-2 parts viscosity modifier, 0.8-1 part pour point depressant, 0.08-0.1 parts defoamer, and 0.8-1 part rust inhibitor; mix the paraffinic base oil, antioxidant lubricating filler, active additive, viscosity modifier, pour point depressant, defoamer, and rust inhibitor, and ultrasonically disperse for 15-20 minutes to obtain an antioxidant lubricating oil composition.

2. The method for preparing an antioxidant lubricating oil composition according to claim 1, characterized in that: The active additive is prepared by the following steps: Step A1: Mix 3,5-di-tert-butyl-2-hydroxybenzaldehyde, N-phenyl-p-phenylenediamine and ethanol, and react under nitrogen protection, stirring at 120-140 rpm and at 70°C for 2-3 hours to obtain the intermediate. Step A2: Mix benzotriazole, formaldehyde solution and deionized water, and react at a stirring rate of 120-140 rpm and a temperature of 80℃ for 30-40 min. Rotary evaporate, filter to obtain filter cake. Mix filter cake, boric acid and toluene, and react at a stirring rate of 120-140 rpm and a temperature of 110℃ for 1.5-2 h. Add intermediate, raise the temperature to 115℃, and continue to react for 2-3 h. Distill under reduced pressure, filter, wash to obtain active additive.

3. The method for preparing an antioxidant lubricating oil composition according to claim 2, characterized in that: In step A1: The ratio of 3,5-di-tert-butyl-2-hydroxybenzaldehyde, N-phenyl-p-phenylenediamine and ethanol is 2.3-2.4 g: 1.85-1.9 g: 40-45 mL.

4. The method for preparing an antioxidant lubricating oil composition according to claim 2, characterized in that: In step A2: The ratio of benzotriazole, formaldehyde solution, deionized water, boric acid, toluene and intermediate is 2.4-2.42g: 45-50mL: 15-20mL: 0.61-0.62g: 35-40mL: 4.2-4.3g, and the mass fraction of formaldehyde solution is 36%.

5. The method for preparing an antioxidant lubricating oil composition according to claim 1, characterized in that: The antioxidant lubricating filler is prepared by the following steps: Step B1: Mix graphene oxide, phosphomolybdic acid and deionized water, and ultrasonically disperse for 30-35 min. Under the conditions of stirring at 300-400 rpm and room temperature, stir and add hexadecyltrimethylammonium bromide, stir for 15-20 min, then add L-cysteine ​​solution, ultrasonically disperse for 10-15 min, transfer to a reaction vessel, react at 180℃ for 24 h, filter, wash, dry, and then transfer to a tube furnace. Under nitrogen protection, heat to 750℃ at 5℃ / min, hold for 2 h, grind to obtain precursor 1; Step B2: Mix precursor 1 with hydrogen peroxide solution and ultrasonically disperse for 15-20 min, let stand for 12 h, filter, and dry to obtain precursor 2. Mix precursor 2, deionized water and ethanol, and ultrasonically disperse for 40-50 min. Under the conditions of stirring speed of 120-180 rpm and temperature of room temperature, stir and add ferric chloride tetrahydrate and ferric chloride hexahydrate, stir for 15-20 min, heat to 80℃, stir and add ammonia water, react for 30-40 min, centrifuge, filter, wash, and dry to obtain precursor 3. Step B3: Mix precursor 3 and isopropanol and ultrasonically disperse for 15-20 min. Under the conditions of stirring speed of 120-180 rpm and temperature of 60℃, stir and add O,O-diisooctyl dithiophosphate. React for 24 h, centrifuge, filter, wash, and dry to obtain antioxidant lubricating filler.

6. The method for preparing an antioxidant lubricating oil composition according to claim 5, characterized in that: In step B1, the ratio of graphene oxide, phosphomolybdic acid, deionized water, hexadecyltrimethylammonium bromide, and L-cysteine ​​solution is 0.04-0.05g: 0.46-0.48g: 20-25mL: 0.008-0.01g: 8-10mL, and the mass concentration of L-cysteine ​​solution is 0.08g / mL.

7. The method for preparing an antioxidant lubricating oil composition according to claim 5, characterized in that: In step B2: the ratio of precursor 1 to hydrogen peroxide solution is 0.45-0.5g:30-35mL, the molar concentration of hydrogen peroxide solution is 5mol / L, and the ratio of precursor 2, deionized water, ethanol, ferric chloride tetrahydrate, ferric chloride hexahydrate, and ammonia is 0.1-0.12g:50-60mL:50-60mL:0.14-0.15g:0.36-0.37g:20-25mL, the mass fraction of ammonia is 15%.

8. The method for preparing an antioxidant lubricating oil composition according to claim 5, characterized in that: In step B3: the ratio of precursor 3, isopropanol and O,O-diisooctyl dithiophosphate is 0.14-0.16g: 80-100mL: 25-30mL.

9. An antioxidant lubricating oil composition, characterized in that: Prepared according to any one of the preparation methods described in claims 1-8.

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