CN113845961B

CN113845961B - Lubricating oil composition for gears and preparation method thereof

Info

Publication number: CN113845961B
Application number: CN202111189953.3A
Authority: CN
Inventors: 黄金匣; 杨玉磊; 余舒玲
Original assignee: Shandong Sanpin New Energy Co ltd
Current assignee: Shandong Sanpin New Energy Co ltd
Priority date: 2021-10-11
Filing date: 2021-10-11
Publication date: 2022-08-12
Anticipated expiration: 2041-10-11
Also published as: CN113845961A

Abstract

The invention discloses a lubricating oil composition for gears and a preparation method thereof, belonging to the technical field of lubricating oil, wherein the lubricating oil composition for gears comprises the following raw materials: poly alpha-olefin, ester oil, antioxidant additive, extreme pressure antiwear agent, silicone oil and viscosity index improver; the preparation method of the lubricating oil composition comprises the following steps: firstly, weighing raw materials; secondly, mixing the poly-alpha-olefin and the ester oil to obtain a mixed solution; then adding an antioxidant additive, an extreme pressure antiwear agent, silicone oil and a viscosity index improver into the mixed solution, uniformly mixing, and filtering to obtain a lubricating oil composition for the gear; the invention prepares the passivation component firstly, then takes the passivation component as the raw material, introduces phenolic hydroxyl into the structure of the passivation component, prepares the antioxidant additive, can provide more effective protection for the oxidation stability of the lubricating oil, and can play a role in resisting wear.

Description

Lubricating oil composition for gears and preparation method thereof

Technical Field

The invention belongs to the technical field of lubricating oil, and particularly relates to a lubricating oil composition for gears and a preparation method thereof.

Background

Along with the factors of the design precision requirement of the gear, streamline design and the like, the operating temperature and the bearing load of the gear are increased, the tolerance between the gears is decreased, and the tangential speed of the gear is increased. Therefore, the development trend of gear oil is to have more excellent oxidation stability and thermal stability to ensure or prolong the oil change period of oil products, and also to have more excellent extreme pressure wear resistance and better antifriction and energy-saving properties.

In general, extreme pressure agents and antiwear agents containing sulfur, phosphorus and chlorine provide excellent extreme pressure antiwear performance for gear oil, and the additives generate acid substances such as sulfuric acid during thermal oxidation, so that the oxidation of oil products is accelerated, and equipment is corroded. Therefore, compared with other types of lubricants with low requirements on extreme pressure wear resistance, the gear oil has more strict requirements on the compatibility synergistic effect of the antioxidant so as to ensure the dual performances of extreme pressure wear resistance and oxidation resistance.

Disclosure of Invention

The invention provides a lubricating oil composition for a gear and a preparation method thereof.

The purpose of the invention can be realized by the following technical scheme:

a lubricating oil composition for gears comprises the following raw materials in parts by weight: 60-90 parts of poly alpha-olefin, 20-40 parts of ester oil, 0.1-3 parts of antioxidant additive, 0.2-5 parts of extreme pressure antiwear agent, 0.05-0.5 part of silicone oil and 5-10 parts of viscosity index improver;

A method for preparing a lubricating oil composition for gears, comprising the steps of:

firstly, weighing raw materials in parts by weight;

secondly, mixing the poly-alpha-olefin and the ester oil to obtain a mixed solution; and then adding an antioxidant additive, an extreme pressure antiwear agent, silicone oil and a viscosity index improver into the mixed solution, uniformly mixing, and filtering to obtain the lubricating oil composition for the gear.

Wherein the ester oil is one of sebacic acid di (2-ethylhexyl) ester and pentaerythritol fatty acid ester; the extreme pressure antiwear agent is one or more of tricresyl phosphate, diisobutyl phosphite and diisooctyl phosphite; the viscosity index improver is one or more of ethylene propylene copolymer, polyisobutylene and polymethacrylate.

Preparing a passivation component:

step S21, mixing 5-amino-2-mercapto-1, 3, 4-thiadiazole, potassium hydroxide and deionized water, stirring for dissolving, then adding ethyl chloroacetate ethanol solution, stirring for reacting for 5h at room temperature, and carrying out post-treatment after the reaction is finished, wherein the post-treatment process comprises the following steps: carrying out suction filtration, washing and drying on the obtained reaction solution to obtain a solid, and recrystallizing the obtained solid with absolute ethyl alcohol to obtain an intermediate a; the dosage ratio of the 5-amino-2-mercapto-1, 3, 4-thiadiazole to the ethanol solution of potassium hydroxide, deionized water and ethyl chloroacetate is 13 mmol: 18.2 mmol: 6mL of: 10mL, ethyl chloroacetate in ethanol as ethyl chloroacetate and ethanol as 13 mmol: 10mL of the mixture is mixed;

The reaction process is as follows:

step S22, mixing the obtained intermediate a with absolute ethyl alcohol, then adding p-nitrobenzaldehyde, dropwise adding glacial acetic acid, carrying out reflux reaction for 4 hours at the temperature of 80 ℃, and carrying out post-treatment after the reaction is finished, wherein the post-treatment process comprises the following steps: concentrating the obtained reaction solution under reduced pressure to remove the solvent, and then purifying by a column to obtain an intermediate b; the dosage ratio of the intermediate a to the absolute ethyl alcohol to the p-nitrobenzaldehyde to the glacial acetic acid is 2.2 g: 40mL of: 1.5 g: 30 mg;

the reaction process is as follows:

step S23, adding the intermediate b into a reaction kettle, then adding a catalyst suspension, stirring and reacting for 10 hours at the temperature of 50 ℃ under normal pressure and under the condition of introducing hydrogen, and carrying out post-treatment after the reaction is finished, wherein the post-treatment process comprises the following steps: carrying out vacuum filtration on the obtained reaction liquid, transferring the filtrate into a rotary evaporator, carrying out vacuum concentration at the temperature of 45 ℃ until the volume of the filtrate is unchanged, and then recrystallizing with the mixed solution to obtain a passivation component; the catalyst suspension is a palladium/carbon catalyst and ethyl acetate according to the dosage ratio of 1 g: 100mL, wherein the dosage ratio of the intermediate b to the catalyst suspension is 1 g: 10 mL; the mixed solution used in the post-treatment process is ethyl acetate and toluene according to a volume ratio of 2: 5, mixing the components.

The reaction process is as follows:

preparing an antioxidant additive:

step S11, adding a passivation component into a hydrochloric acid solution at the temperature of 5 ℃, then adding a sodium nitrite solution, keeping the temperature unchanged, and continuously stirring for reaction for 2 hours to obtain an intermediate 1; the concentration of the hydrochloric acid solution is 5mol/L, the mass fraction of the sodium nitrite solution is 30%, and the dosage ratio of the hydrochloric acid solution, the passivation component and the sodium nitrite solution is 100 mL: 19.3 g: 28g of a mixture;

the reaction process is as follows:

step S12, uniformly stirring deionized water, sodium bicarbonate and p-benzoquinone, adding the intermediate 1, stirring and reacting for 1.5h at the temperature of 12 ℃, then heating to the temperature of 20 ℃, stirring and reacting for 1.5h, and performing post-treatment after the reaction is finished, wherein the post-treatment process comprises the following steps: washing the obtained reaction solution with deionized water, and drying the reaction solution at 60 ℃ under a vacuum condition to constant weight after washing to obtain an intermediate 2; the dosage ratio of the deionized water to the sodium bicarbonate to the p-benzoquinone to the intermediate 1 is 800 mL: 27.2 g: 11.7 g: 36.9 g;

the reaction process is as follows:

step S13, mixing the intermediate 2, zinc powder and deionized water, heating and refluxing at the temperature of 95 ℃, adding a hydrochloric acid solution, continuing heating and refluxing for 4 hours after the hydrochloric acid solution is added, and performing post-treatment after the reaction is finished, wherein the post-treatment process comprises the following steps: carrying out vacuum filtration on the obtained reaction solution while the reaction solution is hot, standing the filtrate at 5 ℃ for 2h, then washing the filtrate with deionized water, and after washing, drying the filtrate at 60 ℃ under a vacuum condition to constant weight to obtain an antioxidant additive; the concentration of the hydrochloric acid solution is 11.8mol/L, and the dosage ratio of the intermediate 2, the zinc powder, the deionized water and the hydrochloric acid solution is 20.6 g: 10.4 g: 200mL of: 15 mL.

The reaction process is as follows:

the invention has the beneficial effects that:

the poly-alpha-olefin and the ester oil are used as base oil, wherein the poly-alpha-olefin is synthetic oil consisting of carbon and hydrogen, has good lubricating property, is non-toxic and has lower cost. The kinematic viscosity of the selected poly-alpha-olefin at 40 ℃ is 80-150 mm/s; the ester oil has good lubricating property and load bearing capacity.

The molecular structure of the passivation component prepared by the invention contains five-membered nitrogen heterocycle, the nitrogen atom on the five-membered nitrogen heterocycle contains lone pair electrons which are not bonded, the lone pair of electrons can be combined with the positive charges left after the electrons escape from the surface of the metal, and can also form coordinate bonds with the empty d orbit of the metal, a stable complexing adsorption passive film is formed on the surface of the metal, the passive film can prevent acidic substances generated in the use of lubricating oil from corroding the metal, in addition, nitrogen can inhibit the corrosion action of sulfur, furthermore, Schiff base with an imino structure in the passivation component has good coordination capacity due to C ═ N double bonds in molecules, and can easily react with metals such as copper to generate a passivation protective film, thereby protecting the metal from being corroded and worn, improving the performances of friction reduction and corrosion resistance, and combining the advantages of Schiff base compounds.

Then, a passivation component is used as a raw material, phenolic hydroxyl is introduced into the structure of the passivation component to prepare an antioxidant additive, the phenolic hydroxyl is matched with an oxygen-containing functional group ester group in the passivation component, so that the antioxidant performance of the lubricating oil is improved, the polar hydroxyl group can improve the wear resistance and extreme pressure resistance of the compound, and the heat stability of the grease is improved due to the existence of a benzene ring. Can provide more effective protection for oxidation stability of lubricating oil and can also play a role in wear resistance.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

Preparing a passivation component:

step S21, mixing 5-amino-2-mercapto-1, 3, 4-thiadiazole, potassium hydroxide and deionized water, stirring for dissolving, then adding ethyl chloroacetate ethanol solution, stirring for reacting for 5h at room temperature, and carrying out post-treatment after the reaction is finished, wherein the post-treatment process comprises the following steps: carrying out suction filtration, washing and drying on the obtained reaction solution to obtain a solid, and recrystallizing the obtained solid with absolute ethyl alcohol to obtain an intermediate a;

Step S22, mixing the obtained intermediate a with absolute ethyl alcohol, then adding p-nitrobenzaldehyde, dropwise adding glacial acetic acid, carrying out reflux reaction for 4 hours at the temperature of 80 ℃, and carrying out post-treatment after the reaction is finished, wherein the post-treatment process comprises the following steps: concentrating the obtained reaction solution under reduced pressure to remove the solvent, and then purifying by a column to obtain an intermediate b;

step S23, adding the intermediate b into a reaction kettle, then adding a catalyst suspension, stirring and reacting for 10 hours at the temperature of 50 ℃ under normal pressure and under the condition of introducing hydrogen, and carrying out post-treatment after the reaction is finished, wherein the post-treatment process comprises the following steps: and carrying out vacuum filtration on the obtained reaction liquid, transferring the filtrate into a rotary evaporator, carrying out vacuum concentration at the temperature of 45 ℃ until the volume of the filtrate is unchanged, and then recrystallizing by using the mixed solution to obtain the passivation component.

Wherein, in the step S21, the dosage ratio of the 5-amino-2-mercapto-1, 3, 4-thiadiazole, the potassium hydroxide, the deionized water and the ethyl chloroacetate in the ethanol solution is 13 mmol: 18.2 mmol: 6mL of: 10mL, ethyl chloroacetate in ethanol as ethyl chloroacetate and ethanol as 13 mmol: 10mL of the mixture is obtained; in the step S22, the dosage ratio of the intermediate a, the absolute ethyl alcohol, the p-nitrobenzaldehyde and the glacial acetic acid is 2.2 g: 40mL of: 1.5 g: 30 mg; in the step S23, the catalyst suspension is a palladium/carbon catalyst and ethyl acetate according to the dosage ratio of 1 g: 100mL, wherein the dosage ratio of the intermediate b to the catalyst suspension is 1 g: 10 mL; the mixed solution used in the post-treatment process is ethyl acetate and toluene according to a volume ratio of 2: 5, mixing the components.

Example 2

The antioxidant additive is prepared by the following steps:

step S11, adding a passivation component into a hydrochloric acid solution at the temperature of 5 ℃, then adding a sodium nitrite solution, keeping the temperature unchanged, and continuously stirring for reaction for 2 hours to obtain an intermediate 1;

step S12, uniformly stirring deionized water, sodium bicarbonate and p-benzoquinone, adding the intermediate 1, stirring and reacting for 1.5h at the temperature of 12 ℃, then heating to the temperature of 20 ℃, stirring and reacting for 1.5h, and performing post-treatment after the reaction is finished, wherein the post-treatment process comprises the following steps: washing the obtained reaction solution with deionized water, and drying the reaction solution at 60 ℃ under a vacuum condition to constant weight after washing to obtain an intermediate 2;

step S13, mixing the intermediate 2, zinc powder and deionized water, heating and refluxing at the temperature of 95 ℃, adding a hydrochloric acid solution, continuing heating and refluxing for 4 hours after the hydrochloric acid solution is added, and performing post-treatment after the reaction is finished, wherein the post-treatment process comprises the following steps: and carrying out vacuum filtration on the obtained reaction solution while the reaction solution is hot, standing the filtrate at 5 ℃ for 2h, then washing the filtrate with deionized water, and after washing, drying the filtrate at 60 ℃ under a vacuum condition to constant weight to obtain the antioxidant additive.

Wherein the concentration of the hydrochloric acid solution in the step S11 is 5mol/L, the mass fraction of the sodium nitrite solution is 30%, and the dosage ratio of the hydrochloric acid solution, the passivation component and the sodium nitrite solution is 100 mL: 19.3 g: 28g of a mixture; in the step S12, the dosage ratio of the deionized water to the sodium bicarbonate to the p-benzoquinone to the intermediate 1 is 800 mL: 27.2 g: 11.7 g: 36.9 g; the concentration of the hydrochloric acid solution in the step S13 is 11.8mol/L, and the dosage ratio of the intermediate 2, the zinc powder, the deionized water and the hydrochloric acid solution is 20.6 g: 10.4 g: 200mL of: 15 mL; the passivation component was prepared as in example 1.

Example 3

firstly, weighing the following raw materials in parts by weight: 60 parts of poly-alpha-olefin, 20 parts of ester oil, 0.1 part of antioxidant additive, 0.2 part of extreme pressure antiwear additive, 0.05 part of silicone oil and 5 parts of viscosity index improver;

Wherein the ester oil is sebacic acid di (2-ethylhexyl) ester; the extreme pressure antiwear agent is tricresyl phosphate; the viscosity index improver is ethylene propylene copolymer; the antioxidant additive was prepared as in example 2.

Example 4

firstly, weighing the following raw materials in parts by weight: 80 parts of poly-alpha-olefin, 30 parts of ester oil, 2 parts of antioxidant additive, 2 parts of extreme pressure antiwear agent, 0.2 part of silicone oil and 8 parts of viscosity index improver;

Wherein the ester oil is pentaerythritol fatty acid ester; the extreme pressure antiwear agent is diisobutyl phosphite; the viscosity index improver is polyisobutylene; the antioxidant additive was prepared as in example 2.

Example 5

firstly, weighing the following raw materials in parts by weight: 90 parts of poly-alpha-olefin, 40 parts of ester oil, 3 parts of antioxidant additive, 5 parts of extreme pressure antiwear agent, 0.5 part of silicone oil and 10 parts of viscosity index improver;

secondly, mixing the poly alpha-olefin and the ester oil to obtain a mixed solution; and then adding an antioxidant additive, an extreme pressure antiwear agent, silicone oil and a viscosity index improver into the mixed solution, uniformly mixing, and filtering to obtain the lubricating oil composition for the gear.

Wherein the ester oil is pentaerythritol fatty acid ester; the extreme pressure antiwear agent is diisooctyl phosphite; the viscosity index improver is polymethacrylate; the antioxidant additive was prepared as in example 2.

Comparative example 1

Compared with the example 4, the antioxidant additive is not added, and the rest raw materials and the preparation process are kept unchanged.

Comparative example 2

The antioxidant additive in example 4 was changed to 2, 6-di-tert-butyl-p-cresol, and the remaining raw materials and preparation process were kept unchanged.

Comparative example 3

This comparative example is the gear oil for vehicles prepared in patent No. CN 103710114B.

The samples prepared in examples 3 to 5 and comparative example 1 were subjected to the test,

the test results are shown in table 1 below:

measuring the oxidation induction period by adopting a high Pressure Differential Scanning Calorimetry (PDSC); the scrub spot diameter was determined using SH/T0189.

TABLE 1

Item	Example 3	Example 4	Example 5	Comparative example 1	Comparative example 2	Comparative example 3
							Initial oxidation temperature/. degree.C	229	230	229	170	205	210
Oxidative induction period/min	51.6	51.7	51.6	20.2	27.1	45.5
							Abrasive grain diameter/d ₆₀ ⁴⁰ ，mm	0.40	0.40	0.40	0.64	0.56	0.48

The higher the initial oxidation temperature, the better the thermal stability of the lubricating oil; the longer the oxidation induction period is, the better the oxidation resistance of the lubricating oil is; the smaller the wear scar diameter, the better the wear resistance of the lubricating oil.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is illustrative and explanatory only and is not intended to be exhaustive or to limit the invention to the precise embodiments described, and various modifications, additions, and substitutions may be made by those skilled in the art without departing from the scope of the invention or exceeding the scope of the claims.

Claims

1. The lubricating oil composition for the gears is characterized by comprising the following raw materials in parts by weight: 60-90 parts of poly alpha-olefin, 20-40 parts of ester oil, 0.1-3 parts of antioxidant additive, 0.2-5 parts of extreme pressure antiwear agent, 0.05-0.5 part of silicone oil and 5-10 parts of viscosity index improver;

wherein, the antioxidant additive is prepared by the following steps:

the structure of the passivation component is shown below:

step S12, uniformly stirring deionized water, sodium bicarbonate and p-benzoquinone, adding the intermediate 1, stirring and reacting for 1.5 hours at the temperature of 12 ℃, then heating to the temperature of 20 ℃, stirring and reacting for 1.5 hours, and performing post-treatment after the reaction is finished to obtain an intermediate 2;

Step S13, mixing the intermediate 2, zinc powder and deionized water, heating and refluxing at the temperature of 95 ℃, adding a hydrochloric acid solution, continuing heating and refluxing for 4 hours after the hydrochloric acid solution is added, and performing post-treatment after the reaction is finished to obtain an antioxidant additive;

the passivation component is prepared by the following steps:

step S21, mixing 5-amino-2-mercapto-1, 3, 4-thiadiazole, potassium hydroxide and deionized water, stirring for dissolving, then adding ethyl chloroacetate ethanol solution, stirring for reacting for 5 hours at room temperature, and performing post-treatment after the reaction is finished to obtain an intermediate a;

step S22, mixing the obtained intermediate a with absolute ethyl alcohol, then adding p-nitrobenzaldehyde, dropwise adding glacial acetic acid, carrying out reflux reaction for 4 hours at the temperature of 80 ℃, and carrying out post-treatment after the reaction is finished to obtain an intermediate b;

step S23, adding the intermediate b into a reaction kettle, then adding a catalyst suspension, stirring and reacting for 10 hours at the temperature of 50 ℃ under normal pressure and under the condition of introducing hydrogen, and carrying out post-treatment after the reaction is finished to obtain a passivation component;

in step S21, the ratio of the amounts of 5-amino-2 mercapto-1, 3, 4-thiadiazole, potassium hydroxide, deionized water, and ethyl chloroacetate in ethanol solution is 13 mmol: 18.2 mmol: 6mL of: 10mL, ethyl chloroacetate in ethanol as ethyl chloroacetate and ethanol as 13 mmol: 10mL of the mixture is mixed; in the step S22, the dosage ratio of the intermediate a, the absolute ethyl alcohol, the p-nitrobenzaldehyde and the glacial acetic acid is 2.2 g: 40mL of: 1.5 g: 30 mg; in the step S23, the catalyst suspension is a palladium/carbon catalyst and ethyl acetate according to the dosage ratio of 1 g: 100mL, wherein the dosage ratio of the intermediate b to the catalyst suspension is 1 g: 10 mL.

2. The lubricating oil composition for gears according to claim 1, wherein the concentration of the hydrochloric acid solution in step S11 is 5mol/L, the mass fraction of the sodium nitrite solution is 30%, and the use ratio of the hydrochloric acid solution, the passivation component and the sodium nitrite solution is 100 mL: 19.3 g: 28g of a mixture; in the step S12, the dosage ratio of the deionized water to the sodium bicarbonate to the p-benzoquinone to the intermediate 1 is 800 mL: 27.2 g: 11.7 g: 36.9 g; the concentration of the hydrochloric acid solution in the step S13 is 11.8mol/L, and the dosage ratio of the intermediate 2, the zinc powder, the deionized water and the hydrochloric acid solution is 20.6 g: 10.4 g: 200mL of: 15 mL.

3. The method for preparing a lubricating oil composition for gears according to claim 1, characterized by comprising the steps of:

firstly, weighing raw materials in parts by weight; secondly, mixing the poly-alpha-olefin and the ester oil to obtain a mixed solution; and then adding an antioxidant additive, an extreme pressure antiwear agent, silicone oil and a viscosity index improver into the mixed solution, uniformly mixing, and filtering to obtain the lubricating oil composition for the gear.