CN115772194B - A cationic functionalized ionic liquid lubricating additive, preparation method and application thereof - Google Patents

Abstract

The invention provides a cationic functionalized ionic liquid lubricating additive, a preparation method and an application. The structural formula is: The preparation method of the ionic liquid lubricating additive is: weighing N-butyldiethanolamine and β-(3,5-di-tert-butyl-4-hydroxyphenyl) methyl propionate in an equal molar ratio of 1:2 and adding them into a single port In the flask, the reaction was stirred for 12 hours at 200°C under reduced pressure with a pressure of -0.090MPa to obtain the intermediate product. This intermediate product was reacted with bis(2-ethylhexyl)phosphate at a molar ratio of 1:1 at a temperature of 100°C and a time of 4 hours to obtain a cationic functionalized ionic liquid. The ionic liquid lubricating additive of the present invention has excellent antioxidant, anti-wear and friction-reducing properties in synthetic esters.

Description

A cationic functionalized ionic liquid lubricating additive, preparation method and application thereof

Technical field

The invention relates to a cationic functionalized ionic liquid lubricating additive, a preparation method and an application thereof, and belongs to the technical field of lubrication.

Background technique

Ionic liquid lubricant additives have gradually become more popular since they were reported in 2001 (Ye C, Liu W, Chen Y, et al. Room-temperatureionic liquids: a novel versatile lubricant[J]. Chemical Communications, 2001(21):2244-2245) Developed as an important branch of lubricating additives, ionic liquids have many excellent properties as lubricating additives, such as low volatility, thermal stability, and excellent anti-wear properties, making them a research hotspot for lubricating additives. However, ionic liquids have high costs and complex preparation processes. Defects such as poor solubility in base oil and strong corrosiveness of halogen-containing ionic liquids limit the widespread use of ionic liquids as lubricating additives.

Synthetic ester is the fifth type of base oil. It has excellent high and low temperature properties, high viscosity index, high flash point, high fire point, and easy biodegradation. It is often used in harsh working conditions where mineral oil, PAO and other base oils are difficult to apply. High-temperature chain oil is a typical application of synthetic esters, such as trimellitate and dipentaerythritol ester, which are the main base oils of high-temperature chain oil. At high temperatures, chain oil is easily oxidized due to its high working temperature (usually higher than 180°C). A certain amount of antioxidants need to be added to improve its oxidation stability. At the same time, in order to maintain good lubricity in the chain drive, it needs to be oxidized at high temperatures. Anti-wear additives are added to the chain oil, and high-temperature chain oil is required to have good antioxidant properties and lubrication properties at the same time.

Contents of the invention

The cationic functionalized ionic liquid lubricating additive prepared by the present invention introduces antioxidant functional groups into cations to achieve both antioxidant and antiwear functions. The preparation process of the present invention is simple and the preparation cost is low. It can be used as a bifunctional additive. Among synthetic esters, especially as a lubricating additive for high-temperature chain oils, it has excellent antioxidant and anti-wear properties.

The purpose of the present invention is to provide a cationic functionalized ionic liquid lubricant additive, a preparation method and its application, and solve the problems of complex ionic liquid preparation process, high preparation cost and single performance in the prior art.

The present invention adopts the following technical solutions:

A cationic functionalized ionic liquid lubricating additive has the structural formula of formula (1):

The preparation method of a cationic functionalized ionic liquid lubricating additive according to the present invention is as follows:

Weigh N-butyldiethanolamine and β-(3,5-di-tert-butyl-4-hydroxyphenyl) methyl propionate with a molar ratio of 1:2 into a single-necked flask, and heat at 200°C under reduced pressure. The reaction was stirred for 12 hours, the pressure was -0.090MPa, and an intermediate product was obtained, which has the structural formula of formula (2).

This intermediate product was reacted with bis(2-ethylhexyl)phosphate at a molar ratio of 1:1 at a temperature of 100°C and a time of 4 hours to obtain a cationic functionalized ionic liquid.

The present invention also provides an application of the cationic functionalized ionic liquid lubricating additive as described above. The ionic liquid lubricating additive is used in synthetic esters. The amount of the ionic liquid lubricating additive in the synthetic ester is based on the mass of the synthetic ester. It is 0.5wt%~2wt%. For example, based on the mass of the synthetic ester, the amount of the ionic liquid lubricating additive in the synthetic ester is 0.5wt%, 1.0wt%, 1.5wt% or 2wt%.

The synthetic ester as described above is one of trimellitic acid ester and dipentaerythritol ester.

Technical features and beneficial effects of the present invention:

Preparation and application of a cationic functionalized ionic liquid lubricant additive according to the present invention. The ionic liquid lubricant additive has dual functions of antioxidant and anti-wear. At the same time, the preparation method of the present invention is simple, the product yield is high, and the preparation cost is low. It has potential value for promotion and application.

Description of the drawings

Figure 1(a) and (b) are the hydrogen and carbon NMR spectra of the intermediate product respectively;

Figure 2(a) and (b) are the hydrogen nuclear magnetic resonance spectrum and carbon spectrum of the cation functionalized ionic liquid respectively.

Detailed ways

The present invention will be further elaborated and illustrated below with reference to specific embodiments.

Example 1

Weigh 8.06g (0.05mol) of N-butyldiethanolamine and 29.24g (0.1mol) of β-(3,5-di-tert-butyl-4-hydroxyphenyl) methyl propionate into a 100ml single-necked flask, at 200 Stir the reaction for 12 hours at ℃, and maintain the pressure at -0.090MPa to obtain the intermediate product, a dark yellow viscous transparent liquid. The nuclear magnetic characterization is shown in Figure 1. The hydrogen spectrum (a) and carbon spectrum (b) of the intermediate product; the obtained intermediate product has the formula ( 2) Structural formula:

Weigh 8.43g (0.02mol) of the above intermediate product and 6.44g (0.02mol) of bis(2-ethylhexyl)phosphate into a 25ml single-neck flask, stir and react at 100°C for 4h to obtain a brown viscous liquid, which is cationic functionalized ion Liquid, NMR characterization is shown in Figure 2, hydrogen spectrum (a) and carbon spectrum (b) of cation functionalized ionic liquid.

The prepared cationic functionalized ionic liquid has the structural formula of formula (1):

Test examples are given below to further illustrate the present invention. The test sample composition of the test example is shown in Table 2. The 40°C viscosity of the base oil trimellitate (Liaocheng Ruijie New Materials Co., Ltd. TMT-3) is 74.4mm ² /s, and the 100°C viscosity is 9.6mm ² /s, the flash point is 276°C, the pour point is -27°C; the 40°C viscosity of the base oil dipentaerythritol ester (Shandong Jule New Material Technology Co., Ltd. Synergy SS T400) is 364.5mm ² /s, and the 100°C viscosity is 24.8 mm ² /s, flash point is 286℃, pour point is -18℃.

Table 2 Composition of test examples and comparative examples

Tribological performance testing

Tribological performance testing was performed on the test examples and comparative examples. Test method: The test equipment is the SRV-V fretting friction and wear testing machine of the German Optimol Grease Company. The test conditions are load 100N, temperature 100°C, frequency 50Hz, stroke 1mm. The time is 30min. The steel ball used in the test is AISI 52100 bearing steel with a diameter of 10mm, and the steel block used in the lower sample is AISI52100 bearing steel with a diameter of 24mm and a height of 7.9±0.1mm. The wear scar diameter of the steel ball on the upper sample was measured using a microscope to characterize the anti-wear performance. The test results are shown in Table 3.

Antioxidant performance test

Test method: The test equipment is a pressurized differential scanning calorimeter (PDSC). The test conditions are the temperature range: 40℃~350℃, the heating rate is 10℃/min, and the sample dosage is 3.00mg±0.05mg. The test results are shown in Table 3.

Table 3 Anti-wear performance and anti-oxidation performance test results of Test Examples 1 to 6, Comparative Example 1, and Comparative Example 2

test sample Steel ball wear spot diameter (mm) Initial oxidation temperature (℃) Test example 1 0.380 217.4 Test example 2 0.348 227.9 Test example 3 0.377 240.9 Test example 4 0.630 228.5 Test example 5 0.592 234.6 Test example 6 0.385 250.7 Comparative example 1 0.527 209.1 Comparative example 2 0.773 214.9

As can be seen from Table 3, compared with Comparative Example 1, the wear scar diameters of Test Examples 1 to 3 decreased by 27.9%, 34.0%, and 28.5%, and the initial oxidation temperature increased by 7.7°C, 18.8°C, and 31.8°C; Compared with Comparative Example 2, the wear scar diameters of Test Examples 4 to 6 decreased by 18.5%, 23.4%, and 50.2%, respectively, and the initial oxidation temperature increased by 13.6°C, 19.7°C, and 35.8°C. Therefore, adding The prepared cationic functionalized ionic liquid can significantly improve the anti-wear performance and antioxidant performance of synthetic ester base oil.

Beneficial effects of the present invention: preparation and application of a cationic functionalized ionic liquid lubricating additive. The ionic liquid lubricating additive has dual functions of antioxidant and anti-wear. At the same time, the preparation method of the present invention is simple, the product yield is high, and the preparation cost is low. , with potential value for popularization and application.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection.

Claims (7)

1. A cationic functionalized ionic liquid lubricating additive, characterized in that the additive has the structural formula of formula (1): 2. The preparation method of lubricating additive according to claim 1, characterized in that the method includes: N-butyldiethanolamine and β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid The intermediate product is obtained by the methyl ester reaction, and the intermediate product is protonated with bis(2-ethylhexyl)phosphate to obtain the cationic functionalized ionic liquid lubricating additive. 3. The preparation method of lubricating additive according to claim 2, characterized in that the obtained intermediate product has the structural formula of formula (2): 4. The preparation method of lubricating additive according to claim 2, characterized in that N-butyldiethanolamine reacts with β-(3,5-di-tert-butyl-4-hydroxyphenyl) methyl propionate. The molar ratio is 1:2, the reaction temperature is 200°C, the reaction time is 12h, and the pressure is -0.090MPa. 5. The preparation method of lubricating additive according to claim 2, characterized in that the intermediate product reacts with bis(2-ethylhexyl)phosphate molar ratio 1:1 at a temperature of 100°C and a time of 4h to obtain cations Functionalized ionic liquids. 6. The application of the lubricating additive according to claim 1, characterized in that the additive is used in synthetic ester, and the additive amount is 0.5wt% to 2wt% based on the mass of the synthetic ester. 7. Application according to claim 6, characterized in that the synthetic ester is trimellitate or dipentaerythritol ester.