High-temperature-resistant anti-corrosion lubricating oil for transmission of electric vehicle

Abstract

The invention discloses high-temperature-resistant anti-corrosion lubricating oil for a gearbox of an electric vehicle, and relates to the technical field of gearbox lubricating oil, the lubricating oil is prepared from the following raw materials by weight: 80-120 parts of base oil, 5-10 parts of modified silicone oil, 1-5 parts of a dispersant, 0.5-3 parts of an anti-wear reagent at extreme pressure, 0.5-3 parts of an antioxidant, 0.05-0.5 part of a metal deactivator, and 0.05-0.5 part of an antifoaming agent. The comprehensive performance of the lubricating oil is improved by improving the component formula, so that the service life of the lubricating oil is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of gearbox lubricating oils, and in particular to a high temperature resistant and corrosion resistant lubricating oil for an electric vehicle gearbox. Background Art

[0002] Electric vehicles are vehicles that use an onboard power source as a driving force, use an electric motor to drive the wheels, and comply with various requirements of road traffic and safety regulations. The high speed and high load of electric vehicle gearboxes make the performance requirements of lubricants different from those of fuel vehicles, especially the cooling, electrical insulation, high temperature oxidation stability, and corrosion resistance of lubricants.

[0003] The lubricity of lubricating oil will gradually lose with the increase of usage time, resulting in increased friction between gears and bearings, and increased wear of the transmission system. In addition, the aging of lubricating oil will reduce its heat dissipation capacity, causing the internal temperature of the gearbox to be too high, affecting the performance and life of the gearbox. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearboxes, and to improve the comprehensive performance of the lubricating oil by improving the component formula, thereby extending the service life of the lubricating oil.

[0005] The technical problem to be solved by the present invention is achieved by adopting the following technical solutions:

[0006] The present invention provides a high temperature resistant and anti-corrosion lubricating oil for an electric vehicle gearbox, which is made of the following raw materials in percentage by weight:

[0007] 80-120 parts of base oil, 5-10 parts of modified silicone oil, 1-5 parts of dispersant, 0.5-3 parts of extreme pressure anti-wear agent, 0.5-3 parts of antioxidant, 0.05-0.5 parts of metal deactivator, and 0.05-0.5 parts of defoaming agent.

[0008] Furthermore, the modified silicone oil is a thiourea grafted modified silicone oil, and its preparation method is: adding double-terminal hydrogen-containing silicone oil, 1,3-diallyl-2-thiourea and chloroplatinic acid to an organic solvent, carrying out a hydrosilylation reaction under nitrogen protection, and after the reaction is completed, removing the organic solvent by reduced pressure distillation to obtain the thiourea grafted modified silicone oil.

[0009] The present invention uses thiourea grafted modified silicone oil to replace the commonly used ethylene-propylene copolymer in the field as a viscosity index improver, which not only has good viscosity increasing ability and shear stability, but also can improve the thermal conductivity of the lubricating oil, thereby enhancing the heat dissipation effect of the lubricating oil.

[0010] Preferably, the organic solvent includes, but is not limited to, one or more of methanol, isopropanol, acetone, toluene, and tetrahydrofuran.

[0011] Preferably, the molar ratio of the double-terminal hydrogen-containing silicone oil to 1,3-diallyl-2-thiourea is 1:(1-2); the amount of chloroplatinic acid used is 30-50ppm of the mass of the end-hydrogen-containing silicone oil. It is necessary to control the amounts of the double-terminal hydrogen-containing silicone oil, 1,3-diallyl-2-thiourea and chloroplatinic acid to synthesize the thiourea grafted modified silicone oil that can replace the ethylene-propylene copolymer as a viscosity index improver.

[0012] Common catalysts for the hydrosilylation reaction include platinum compounds, palladium compounds, rhodium compounds, nickel compounds and other metal compounds, among which platinum compounds include chloroplatinic acid and palladium compounds include tetrakis(triphenylphosphine)palladium, bistriphenylphosphine palladium dichloride and the like.

[0013] Furthermore, the base oil is one or more of Class II hydrogenated base oil, Class III hydrogenated base oil, and polyalphaolefin. Hydrogenated base oil is a base oil whose chemical composition is changed by hydrogenation process, so that its color, stability and odor are improved, its viscosity-temperature performance is improved, and its sensitivity to antioxidants is also significantly improved. Polyalphaolefin synthetic oil has good viscosity-temperature performance and low-temperature fluidity, and is an ideal base oil for preparing high-grade and special lubricants.

[0014] Furthermore, the dispersant is polyisobutylene succinimide. The function of the dispersant is to disperse insoluble impurities in the lubricating oil to prevent precipitation, oxidation and corrosion, thereby extending the service life of the lubricating oil and the gearbox.

[0015] Furthermore, the extreme pressure anti-wear agent is one or more of organic chlorides, organic sulfides, organic phosphides, organic metal salts, and borates.

[0016] Furthermore, the antioxidant is one or more of a phenolic antioxidant and an amine antioxidant. During use, the lubricating oil will inevitably come into contact with air and oxidize, causing the lubricating oil to deteriorate and shorten the service life of the lubricating oil. The function of the antioxidant is to slow down the oxidation process of the lubricating oil and extend the service life of the lubricating oil.

[0017] Furthermore, the metal deactivator is one or more of benzotriazole and its derivatives, thiadiazole and its derivatives. The metal deactivator is used to prevent the metal from promoting the auto-oxidation of the lubricating oil, and is used in combination with the antioxidant to produce a synergistic effect, showing excellent copper corrosion inhibition and antioxidant properties.

[0018] Furthermore, the defoamer is one or more of a polyether defoamer, a silicone defoamer, and a polyether-modified silicone defoamer. The presence of foam will affect the lubricating properties of the lubricating oil and reduce the lubricating effect. The function of the defoamer is to reduce the amount of foam in the lubricating oil and improve the lubricating effect.

[0019] The beneficial effects of the present invention are as follows: the present invention prepares lubricating oil by adding appropriate proportions of viscosity index improver, dispersant, extreme pressure anti-wear agent, antioxidant, metal deactivator and defoaming agent to base oil, and the lubricating oil has excellent lubrication and cooling properties, and good high temperature resistance and corrosion resistance, so that the lubricating oil can still maintain a good lubrication effect in a high temperature environment, reduce the corrosion of metal parts, effectively extend the service life of the lubricating oil, and meet the use requirements of electric vehicle gearbox lubricating oil. DETAILED DESCRIPTION

[0020] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments.

[0021] The hydrogen content of the double-terminal hydrogen-containing silicone oil in the following examples and comparative examples is 0.19 mmol / g; the allyl polyether is APEG-700.

[0022] Example 1

[0023] Preparation of thiourea grafted modified silicone oil: Add 0.1 mol of double-terminal hydrogenated silicone oil, 0.1 mol of 1,3-diallyl-2-thiourea and chloroplatinic acid to isopropanol, the amount of chloroplatinic acid is 50 ppm of the mass of the end-hydrogenated silicone oil, heat to 80°C under nitrogen protection and react for 5 hours. After the reaction, remove isopropanol by reduced pressure distillation to obtain thiourea grafted modified silicone oil.

[0024] Preparation of lubricating oil: 80 parts of Class II hydrogenated base oil 150N, 5 parts of thiourea grafted modified silicone oil, 3 parts of polyisobutylene succinimide, 2 parts of dibutyl phosphite, 1 part of 2,6-di-tert-butyl-p-cresol, 0.5 parts of methylbenzotriazole and 0.3 parts of polyether defoamer L61 were mixed uniformly to obtain lubricating oil.

[0025] Example 2

[0026] Preparation of thiourea grafted modified silicone oil: Add 0.1 mol of double-terminal hydrogenated silicone oil, 0.2 mol of 1,3-diallyl-2-thiourea and chloroplatinic acid to isopropanol, the amount of chloroplatinic acid used is 30 ppm of the mass of the end-hydrogenated silicone oil, heat to 80°C under nitrogen protection and react for 5 hours. After the reaction, remove isopropanol by reduced pressure distillation to obtain thiourea grafted modified silicone oil.

[0027] Preparation of lubricating oil: 100 parts of poly-α-olefin SpectraSyn Plus4, 8 parts of thiourea grafted modified silicone oil, 3 parts of polyisobutylene succinimide, 2 parts of dibutyl phosphite, 1 part of octyl diphenylamine, 0.5 parts of methyl benzotriazole and 0.5 parts of silicone defoamer BYK-066N were mixed uniformly to obtain lubricating oil.

[0028] Example 3

[0029] The preparation of thiourea grafted modified silicone oil is the same as in Example 2.

[0030] Preparation of lubricating oil: 120 parts of Class III hydrogenated base oil VHVI-4, 10 parts of thiourea grafted modified silicone oil, 4 parts of polyisobutylene succinimide, 3 parts of dibutyl phosphite, 1 part of 2,6-di-tert-butyl-p-cresol, 0.5 parts of 5-propyl-2-amino-1,3,4-thiadiazole and 0.3 parts of polyether modified silicone defoamer ZH-7011 were mixed uniformly to obtain lubricating oil.

[0031] Example 4

[0032] The preparation of thiourea grafted modified silicone oil is the same as in Example 2.

[0033] Preparation of lubricating oil: 100 parts of polyalphaolefin SpectraSyn Plus4, 5 parts of thiourea grafted modified silicone oil, 2 parts of polyisobutylene succinimide, 1.5 parts of sulfided isobutylene, 1 part of octyl diphenylamine, 0.3 parts of 5-propyl-2-amino-1,3,4-thiadiazole and 0.3 parts of polyether defoamer L61 were mixed uniformly to obtain lubricating oil.

[0034] Example 5

[0035] The preparation of thiourea grafted modified silicone oil is the same as in Example 2.

[0036] Preparation of lubricating oil: 110 parts of polyalphaolefin SpectraSyn Plus4, 8 parts of thiourea grafted modified silicone oil, 3 parts of polyisobutylene succinimide, 2 parts of sulfided isobutylene, 1 part of 2,6-di-tert-butyl-p-cresol, 0.5 parts of methylbenzotriazole and 0.5 parts of silicone defoamer BYK-066N are mixed uniformly to obtain lubricating oil.

[0037] Comparative Example 1

[0038] Comparative Example 1 is to replace the thiourea grafted modified silicone oil in Example 2 with polyether grafted modified silicone oil.

[0039] Preparation of polyether grafted modified silicone oil: Add 0.1 mol of double-terminal hydrogenated silicone oil, 0.2 mol of allyl polyether and chloroplatinic acid to isopropanol, the amount of chloroplatinic acid used is 30 ppm of the mass of the end-terminal hydrogenated silicone oil, heat to 80°C under nitrogen protection and react for 5 hours. After the reaction is completed, remove isopropanol by reduced pressure distillation to obtain polyether grafted modified silicone oil.

[0040] Preparation of lubricating oil: 100 parts of poly-alpha-olefin SpectraSyn Plus4, 8 parts of polyether grafted modified silicone oil, 3 parts of polyisobutylene succinimide, 2 parts of dibutyl phosphite, 1 part of octyl diphenylamine, 0.5 parts of methyl benzotriazole and 0.5 parts of silicone defoamer BYK-066N were mixed uniformly to obtain lubricating oil.

[0041] Comparative Example 2

[0042] Comparative Example 2 is a method in which the thiourea grafted modified silicone oil in Example 2 is replaced by unmodified double-terminal hydrogen-containing silicone oil.

[0043] Preparation of lubricating oil: 100 parts of polyalphaolefin SpectraSyn Plus4, 8 parts of double-terminal hydrogenated silicone oil, 3 parts of polyisobutylene succinimide, 2 parts of dibutyl phosphite, 1 part of octyl diphenylamine, 0.5 parts of methyl benzotriazole and 0.5 parts of silicone defoamer BYK-066N were mixed uniformly to obtain lubricating oil.

[0044] Comparative Example 3

[0045] Comparative Example 3 replaces the thiourea grafted modified silicone oil in Example 2 with T613 ethylene-propylene copolymer.

[0046] Preparation of lubricating oil: 100 parts of poly-alpha-olefin SpectraSyn Plus4, 8 parts of T613 ethylene-propylene copolymer, 3 parts of polyisobutylene succinimide, 2 parts of dibutyl phosphite, 1 part of octyl diphenylamine, 0.5 parts of toluene triazole and 0.5 parts of silicone defoamer BYK-066N were mixed uniformly to obtain lubricating oil.

[0047] The lubricating oils prepared in the above Examples 1-5 and Comparative Examples 1-3 were subjected to performance tests, and the test results are shown in Table 1.

[0048] Thermal conductivity is tested according to standard ASTM D7896-19;

[0049] Test kinematic viscosity according to standard GB / T 265-1988;

[0050] The corrosion level of copper sheets was tested according to standard GB / T 5096-2017, and the test conditions were 150°C and 192h.

[0051] Table 1

[0052]

[0053]

[0054] As can be seen from Table 1, the lubricating oil prepared in the embodiment of the present invention has excellent heat dissipation effect and anti-corrosion performance, and the use of thiourea grafted modified silicone oil instead of ethylene-propylene copolymer as a viscosity index improver can achieve similar viscosity-temperature performance. The addition of thiourea grafted modified silicone oil is also conducive to further improving the heat dissipation effect of the lubricating oil. Compared with the unchemically modified double-terminal hydrogen-containing silicone oil and the T613 ethylene-propylene copolymer commonly used in the art, the use of 1,3-diallyl-2-thiourea to graft-modify the double-terminal hydrogen-containing silicone oil can make the prepared lubricating oil have a better heat dissipation effect.

[0055] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearbox, characterized in that: Made from the following raw materials in weight percentage: 80-120 parts of base oil, 5-10 parts of modified silicone oil, 1-5 parts of dispersant, 0.5-3 parts of extreme pressure anti-wear agent, 0.5-3 parts of antioxidant, 0.05-0.5 parts of metal deactivator, and 0.05-0.5 parts of defoaming agent.

2. The high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearbox according to claim 1, characterized in that: The modified silicone oil is thiourea grafted modified silicone oil, and its preparation method is: adding double-terminal hydrogen-containing silicone oil, 1,3-diallyl-2-thiourea and chloroplatinic acid into an organic solvent, carrying out a hydrosilylation reaction under nitrogen protection, and removing the organic solvent by reduced pressure distillation after the reaction is completed to obtain the thiourea grafted modified silicone oil.

3. The high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearbox according to claim 2, characterized in that: The organic solvent is one or more of methanol, isopropanol, acetone, toluene and tetrahydrofuran.

4. The high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearbox according to claim 2, characterized in that: The molar ratio of the double-terminal hydrogen-containing silicone oil to 1,3-diallyl-2-thiourea is 1:(1-2); the amount of chloroplatinic acid used is 30-50ppm of the mass of the double-terminal hydrogen-containing silicone oil.

5. The high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearbox according to claim 1, characterized in that: The base oil is one or more of a type II hydrogenated base oil, a type III hydrogenated base oil, and poly-α-olefin.

6. The high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearbox according to claim 1, characterized in that: The dispersant is polyisobutylene succinimide.

7. The high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearbox according to claim 1, characterized in that: The extreme pressure anti-wear agent is one or more of organic chlorides, organic sulfides, organic phosphides, organic metal salts and borates.

8. The high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearbox according to claim 1, characterized in that: The antioxidant is one or more of phenolic antioxidants and amine antioxidants.

9. The high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearbox according to claim 1, characterized in that: The metal deactivator is one or more of benzotriazole and its derivatives, thiadiazole and its derivatives.

10. The high temperature resistant and anti-corrosion lubricating oil for electric vehicle gearbox according to claim 1, characterized in that: The defoamer is one or more of a polyether defoamer, a silicone defoamer, and a polyether-modified silicone defoamer.

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