Antioxidant and antiwear difunctional lubricating additive, and preparation method and application thereof

Abstract

The invention provides an antioxidant and antiwear difunctional lubricating additive, a preparation method and application thereof, the name is (3, 5-di-tert-butyl-4-hydroxyphenyl) methyl dibutyl phosphonate, and the structural formula is # imgabs0. The antioxidant and antiwear difunctional lubricating additive is prepared by taking 2, 6-di-tert-butyl-p-(dimethylaminomethyl) phenol and dibutyl phosphite as raw materials through a one-step reaction under the conditions that the raw materials are mixed, and then the antioxidant and antiwear difunctional lubricating additive is prepared. The preparation method comprises the following steps: reacting at the temperature of 80-100 DEG C and the vacuum degree of 0.080-0.100 MPa for 2-5 hours to obtain a crude product, adding petroleum ether, dissolving, recrystallizing and drying to obtain a final product. The anti-oxidation and anti-wear dual-function lubricating additive has anti-oxidation performance and excellent anti-wear and anti-friction performance. The antioxidant and wear-resistant dual-functional lubricating additive is suitable for high-temperature chain oil taking synthetic ester as base oil, and is used for improving the high-temperature antioxidant and high-temperature wear-resistant properties of the high-temperature chain oil.

Description

Technical Field

[0001] The invention relates to the technical field of lubricating oil additives, and in particular to an anti-oxidation and anti-wear dual-function lubricating additive, a preparation method and application thereof. Background Art

[0002] High temperature chain oil, a fully synthetic high-performance lubricant, protects and lubricates the chain at high temperatures (working temperature > 180°C). In addition, it also has certain anti-corrosion, anti-rust, cleaning, and chain operation noise reduction functions. High temperature chain oil is particularly suitable for precision instruments, mechanical parts under high temperature conditions, heavy-duty high-load equipment and other equipment, and has a wide range of applications, such as textile industry shaping machines, sheet production, glass fiber production lines, automobile factory paint lines, etc. High temperature chain oil is usually based on synthetic esters, such as trimellitic acid esters, dipentaerythritol esters, etc. However, there are very few anti-wear additives suitable for high temperature conditions. Tricresol phosphate is more commonly used in the industry. Due to its low phosphorus content and relatively inertness, during use, an efficient lubricating film cannot be formed between the friction pairs, resulting in increased wear and friction of the friction pairs, thereby affecting the service life of the equipment. Some anti-wear additives with excellent lubrication performance, such as dibutyl phosphite, are difficult to use in high temperature (> 100°C) occasions due to their low decomposition temperature and high reaction activity.

[0003] The present invention prepares a dibutyl phosphite derivative by adjusting and modifying the structure of dibutyl phosphite, which greatly improves the thermal stability deficiency of dibutyl phosphite. The dibutyl phosphite derivative can be applied to high-temperature chain oil (operating temperature>180°C) and has excellent anti-wear performance, which is significantly improved compared with the traditional tricresol phosphate anti-wear agent. In addition, the dibutyl phosphite derivative also has certain antioxidant properties and is a dual-functional lubricating additive with both antioxidant and anti-wear functions. Summary of the invention

[0004] The purpose of the present invention is to provide an antioxidant and anti-wear dual-function lubricating additive, a preparation method and an application thereof. The antioxidant and anti-wear dual-function lubricating additive has excellent high-temperature anti-wear performance in synthetic ester base oil, and at the same time, has good antioxidant performance, and the antioxidant effect is better than that of traditional phenolic antioxidants.

[0005] The invention discloses an anti-oxidation and anti-wear dual-function lubricating additive, which has simple preparation process and high yield.

[0006] The present invention is achieved through the following technical solutions:

[0007] An anti-oxidation and anti-wear dual-function lubricating additive, the structure of the anti-oxidation and anti-wear dual-function lubricating additive is as follows:

[0008] ;

[0009] (1) Dibutyl (3,5-di-tert-butyl-4-hydroxyphenyl)methylphosphonate.

[0010] A method for preparing the antioxidant and anti-wear dual-functional lubricating additive as described above, the method comprising: using 2,6-di-tert-butyl-p-(dimethylaminomethyl)phenol and dibutyl phosphite as raw materials, reacting for 2-5 hours (for example, 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours or 5 hours) at a temperature of 80-100°C (for example, 80°C, 85°C, 90°C, 95°C or 100°C) and a vacuum degree of 0.080-0.100MPa (for example, 0.080 MPa, 0.085MPa, 0.090 MPa, 0.095MPa or 0.100MPa) to obtain a crude product, adding petroleum ether to dissolve, recrystallize and dry to obtain a final product.

[0011] Specifically, a method for preparing the anti-oxidation and anti-wear dual-functional lubricating additive as described above comprises the following steps:

[0012] Take 2,6-di-tert-butyl-p-(dimethylaminomethyl)phenol and dibutyl phosphite in a molar ratio of 1:1 and add them into a reaction bottle, react at a temperature of 90°C and a vacuum degree of 0.090 MPa for 3 hours to obtain a crude product, add petroleum ether, and completely dissolve the crude product at 60°C. After cooling to room temperature and recrystallizing for 24 hours, filter, wash with petroleum ether, and vacuum dry to obtain the final product.

[0013] The present invention also provides an application of the anti-oxidation and anti-wear dual-function lubricating additive as described above, wherein the anti-oxidation and anti-wear dual-function lubricating additive is used in a synthetic ester base oil, and the amount of the anti-oxidation and anti-wear dual-function lubricating additive in the base oil is 0.5 wt% to 2 wt% based on the mass of the base oil. For example, the amount of the anti-oxidation and anti-wear dual-function lubricating additive in the base oil is 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, 1.1 wt%, 1.2 wt%, 1.3 wt%, 1.4 wt%, 1.5 wt%, 1.6 wt%, 1.7 wt%, 1.8 wt%, 1.9 wt% or 2 wt% based on the mass of the base oil.

[0014] Technical features and beneficial effects of the present invention:

[0015] The present invention discloses an anti-oxidation and anti-wear dual-functional lubricating additive, a preparation method and an application thereof. The preparation process of the anti-oxidation and anti-wear dual-functional lubricating additive is simple and the yield is high. The additive exhibits excellent high-temperature anti-wear performance in a synthetic ester base oil. Meanwhile, the anti-oxidation and anti-wear dual-functional lubricating additive has excellent antioxidant performance and has a better antioxidant effect than traditional phenolic antioxidants. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is the infrared spectrum of the anti-oxidation and anti-wear dual-functional lubricating additive prepared in Example 1 of the present invention.

[0017] Figure 2 This is the mass spectrum of the anti-oxidation and anti-wear dual-functional lubricating additive prepared in Example 1 of the present invention.

[0018] Figure 3 This is the thermogravimetric diagram of the anti-oxidation and anti-wear dual-functional lubricating additive prepared in Example 1 of the present invention.

[0019] Figure 4 A comparison chart of the initial oxidation temperatures of the oil samples containing the base oil and the base oil with 0.5wt%, 1.0wt% and 2.0wt% of the anti-oxidation and anti-wear dual-functional lubricating additive prepared in Example 1 added thereto, respectively.

[0020] Figure 5 The comparison chart of the oxidation induction period at 210°C is a graph showing the oil samples to which 1.0wt% L135, 1.0wt% L101 and 1.0wt% of the antioxidant and anti-wear dual-functional lubricating additive prepared in Example 1 were added respectively into the base oil.

[0021] Figure 6 Comparison of the wear scar sizes after friction at different temperatures (a, b, c are 180°C, d, e, f are 210°C) for base oil (a, d), base oil with 1.0wt% tricresyl phosphate added (b, e), and base oil with 1.0wt% of the antioxidant and anti-wear dual-functional lubricating additive prepared in Example 1 added (c, f). DETAILED DESCRIPTION

[0022] The present invention is further described and illustrated below in conjunction with specific embodiments and drawings.

[0023] Example 1

[0024] Weigh 10.52g (0.04mol) of 2,6-di-tert-butyl-p-(dimethylaminomethyl)phenol and 7.77g (0.04mol) of dibutyl phosphite and add them into a 100ml three-necked flask in turn, react at 90°C and vacuum degree 0.090MPa for 3h, cool to room temperature to obtain a crude product. Add 50ml of petroleum ether and heat to 60°C, stir until completely dissolved, cool to room temperature for recrystallization, filter after 24h to obtain yellow solid particles, rinse the filtrate three times with petroleum ether, and dry in a vacuum oven at 50°C for 3h to obtain the final product, weighing 15.4g, with a yield of 93%.

[0025] Infrared spectroscopy analysis:

[0026] Figure 1This is the infrared spectrum of the product of Example 1, the test range is 600cm -1 ~4000cm -1 .3650cm -1 Phenolic hydroxyl absorption peak, 3200cm -1 is the absorption peak after the association of phenolic hydroxyl groups, 1260 cm -1 P=O absorption peak, 1057cm -1 POC absorption peak, 640cm -1 The absorption peak of PC is at 2420 cm -1 The PH absorption peak at disappeared, indicating that the PH bond in dibutyl phosphite was completely converted into PC bond.

[0027] Mass spectrometry analysis:

[0028] Figure 2 The mass spectrum (ESI-MS, negative ion mode) of the product of Example 1 can be seen from the figure. It can be seen that the quasi-molecular ion peak m / z is 411.2666, which is inferred to be formed by removing one hydrogen from the parent molecule (3,5-di-tert-butyl-4-hydroxyphenyl) methylphosphonic acid dibutyl ester (molecular weight 412.27). Combined with infrared analysis, it can be proved that the product of Example 1 is (3,5-di-tert-butyl-4-hydroxyphenyl) methylphosphonic acid dibutyl ester.

[0029] Thermogravimetric analysis:

[0030] Figure 3 The thermogravimetric curves of the product of Example 1 and dibutyl phosphite are shown in the following test conditions: the protective gas is nitrogen, the purge gas is air, the flow rate is 80 ml / min, the heating rate is 10°C / min, and the temperature range is 30°C to 700°C. The initial decomposition temperature of the prepared anti-oxidation and anti-wear dual-functional lubricating additive is 307.7°C, which is higher than the initial decomposition temperature of dibutyl phosphite of 155.1°C. It can be seen that the thermal stability of the prepared anti-oxidation and anti-wear dual-functional lubricating additive is significantly improved compared with dibutyl phosphite, and is suitable for use in higher temperature conditions.

[0031] In order to better understand the tribological properties and antioxidant properties of the prepared anti-oxidation and anti-wear dual-functional lubricating additive, the product of Example 1 and commonly used anti-oxidation or anti-wear additives were added to the base oil to obtain lubricating oil samples. The specific implementation plan is shown in Table 1.

[0032] Table 1 Composition of Examples 2-4 and Comparative Examples 1-4

[0033]

[0034] Note: The viscosity of trimellitate base oil at 40°C is 71.9 mm 2 / s, viscosity at 100℃ 9.5 mm2 / s; L135 and L101 are phenolic antioxidants produced by BASF; tricresyl phosphate is an anti-wear agent.

[0035] Antioxidant performance test:

[0036] Comparative Example 1, Example 2, Example 3, and Example 4 were tested for initial oxidation temperature. The test instrument was a PDSC high pressure differential scanning calorimeter. The test conditions were: 3 mg ± 0.05 mg oil sample, nitrogen as protective gas, pressure 3.5 MPa, oxygen flow rate 100 ml / min, temperature range 30-350 ° C. The test results are shown in Figure 4 .

[0037] from Figure 4 It can be seen that the initial oxidation temperatures of Example 2, Example 3, and Example 4 are all higher than those of Comparative Example 1. The initial oxidation temperature of the trimellitate base oil is 206.3°C, and the initial oxidation temperatures of the oil samples to which 0.5wt%, 1wt%, and 2wt% of the product of Example 1 are added increase by 15.7°C, 28.8°C, and 35.9°C, respectively. It can be seen that the prepared antioxidant and anti-wear dual-functional lubricating additive has better antioxidant properties than the trimellitate base oil.

[0038] Furthermore, the antioxidant performance of the product of Example 1 was compared with that of a traditional phenolic antioxidant, and the oxidation induction period was tested using a PDSC high pressure differential scanning calorimeter. The test conditions were: 3 mg ± 0.05 mg of oil sample, nitrogen as protective gas, pressure of 3.5 MPa, oxygen flow rate of 100 ml / min, and temperature of 210°C. The test results are shown in Figure 5 .

[0039] from Figure 5 It can be seen that the oxidation induction period of Comparative Example 2 is 4.7 min; the oxidation induction period of Comparative Example 3 is 6.9 min, and the oxidation induction period of Example 3 is 12.0 min. It can be seen that the prepared antioxidant and anti-wear dual-functional lubricating additive has better antioxidant performance than traditional phenolic antioxidants.

[0040] Tribological performance test:

[0041] The test instrument is SRV- The upper friction pair is a φ10mm steel ball, and the lower friction pair is a φ24×7.9mm steel block. The material is GCr15 steel, and the contact mode is point contact. The test conditions are: test load 50N, stroke 1mm, frequency 50Hz, test time 1800s, and test temperatures are 180℃ and 210℃ respectively.

[0042] The test oil samples are comparative example 1, comparative example 4 and embodiment 3. The test results of tribological properties are shown in Table 2 and Figure 6 shown.

[0043] Table 2 Wear spot diameter of the upper friction pair after reciprocating friction test of three oil samples at different temperatures

[0044]

[0045] From the results in Table 2, it can be seen that the wear spot diameter of the base oil after the friction test at 180°C and 210°C is the largest, which is 0.738mm and 0.772mm respectively; after adding 1.0wt% of tricresyl phosphate, the wear spot diameter of the oil sample at 180°C and 210°C decreases by 42.1% and 38.9% respectively; after adding 1.0wt% of the product of Example 1, the wear spot diameter of the oil sample at 180°C and 210°C decreases by 50.4% and 54.4% respectively. The anti-wear performance of the product of Example 1 at high temperature is better than that of the traditional anti-wear agent tricresyl phosphate. Figure 6 It can also be seen from the surface morphology of the middle and lower friction pairs that the anti-wear performance of the oil sample in which 1.0wt% of trimellitate is added to the product of Example 1 is better than the oil sample in which 1.0wt% of tricresyl phosphate is added to trimellitate, and both have better anti-wear performance than the base oil.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An anti-oxidation and anti-wear dual-function lubricating additive, characterized in that: The anti-oxidation and anti-wear dual-function lubricating additive has a structural formula (1): (1)。 2. The method for preparing the anti-oxidation and anti-wear dual-function lubricating additive according to claim 1, characterized in that: The method comprises: taking 2,6-di-tert-butyl-p-(dimethylaminomethyl)phenol and dibutyl phosphite as raw materials, reacting for 2-5 hours at a temperature of 80-100°C and a vacuum degree of 0.080-0.100 MPa to obtain a crude product, adding petroleum ether to dissolve, recrystallizing, and drying to obtain a final product.

3. The method for preparing the anti-oxidation and anti-wear dual-function lubricating additive according to claim 2, characterized in that The molar ratio of 2,6-di-tert-butyl-p-(dimethylaminomethyl)phenol to dibutyl phosphite is 1:

1.

4. The use of the anti-oxidation and anti-wear dual-function lubricating additive according to claim 1, characterized in that: The anti-oxidation and anti-wear dual-function lubricating additive is added to the base oil, and the amount of the anti-oxidation and anti-wear dual-function lubricating additive added is 0.5wt% to 2.0wt% of the base oil based on the mass of the base oil.

5. The use of the anti-oxidation and anti-wear dual-function lubricating additive according to claim 4, characterized in that: The base oil is a synthetic ester.

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