A binary polymer lubricating oil pour point depressant and its preparation and application

Abstract

The present invention relates to the technical field of lubricating oils, and in particular to a binary polymer lubricating oil pour point depressant, and its preparation and application. When preparing the binary polymer lubricating oil pour point depressant, methacrylate high carbon ester and 2-ethyleneoxyethanol are mixed in a solvent, an initiator is added after post-treatment, and a polymerization reaction is performed to obtain a binary polymer lubricating oil pour point depressant: methacrylate tetradecyl-2-ethyleneoxyethanol binary polymer. The binary polymer lubricating oil pour point depressant of the present invention can reduce the low-temperature viscosity and freezing point of the lubricating oil, improve the low-temperature fluidity of the lubricating oil, and the pour point depressant does not contain sulfur, phosphorus, and nitrogen, and belongs to a green strong oil-soluble lubricating oil pour point depressant.

Description

Technical Field

[0001] The invention relates to the technical field of lubricating oils, and in particular to a binary polymer lubricating oil pour point depressant and the preparation and application thereof. Background Art

[0002] Lubricating oil has a wide range of applications, but in winter or in extremely cold areas, as the temperature drops, the viscosity of the lubricating oil gradually increases, which affects the cold flow characteristics of the lubricating oil and the normal use of parts. Lubricating oil additives are additives that can significantly reduce the freezing point of lubricating oil, generally high molecular organic compounds. Compared with mixing low freezing point oils into lubricating oil, the synthesis method of lubricating oil pour point depressants is simple, and the freezing point of lubricating oil can be significantly reduced at a low addition amount. Summary of the invention

[0003] In order to solve the above problems, the purpose of the present invention is to provide a binary polymer lubricating oil pour point depressant and its preparation and application. The present invention aims to improve the cold flow performance of lubricating oil by preparing a new green lubricating oil pour point depressant, so that the prepared pour point depressant can reduce the pour point of lubricating oil at a low addition amount, so as to overcome the technical problems of poor oil solubility and poor pour point depressing effect of existing pour point depressants.

[0004] The binary polymer lubricating oil pour point depressant of the invention is generated by free radical polymerization of high carbon methacrylate and 2-ethyleneoxyethanol under heating conditions, and can reduce the low-temperature viscosity and freezing point of the lubricating oil, improve the low-temperature fluidity of the lubricating oil, and the lubricating oil pour point depressant does not contain sulfur, phosphorus and nitrogen, and is a green strong oil-soluble lubricating oil pour point depressant.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] The first object of the present invention is to provide a method for preparing a binary polymer lubricating oil pour point depressant, comprising the following steps:

[0007] The high carbon methacrylate and 2-ethyleneoxyethanol are mixed in a solvent, and an initiator is added after post-treatment to carry out polymerization reaction to obtain a binary polymer lubricating oil pour point depressant: tetradecyl methacrylate-2-ethyleneoxyethanol binary polymer.

[0008] In the present invention, the reaction equation for the preparation process of the binary polymer lubricating oil pour point depressant is shown below:

[0009]

[0010] In one embodiment of the present invention, the preparation method of methacrylate high carbon ester is as follows:

[0011] The polymerization inhibitor, methacrylic acid and higher alcohol are mixed in a solvent, and then a catalyst is added to react to obtain a higher carbon methacrylate.

[0012] In one embodiment of the present invention, the molar ratio of the polymerization inhibitor, methacrylic acid and the higher alcohol is 0.8-1.3:1;

[0013] The amount of solvent added is 1-2 times the total mass of methacrylic acid and higher alcohol;

[0014] The amount of polymerization inhibitor added is 0.6-0.9% of the total mass of methacrylic acid and higher alcohol

[0015] The added amount of the catalyst is 1.2-1.8% of the total mass of methacrylic acid and higher alcohol.

[0016] In one embodiment of the present invention, the molar ratio of the polymerization inhibitor to methacrylic acid is 1.2:1.

[0017] In one embodiment of the present invention, the polymerization inhibitor is selected from one of hydroquinone, p-hydroxyanisole or p-benzoquinone;

[0018] The higher alcohol is selected from one or more of tetradecanol, hexadecanol or octadecanol;

[0019] The solvent is selected from one of toluene, xylene or dioxane;

[0020] The catalyst is selected from one of p-toluenesulfonic acid, oxalic acid or trifluoromethanesulfonic acid;

[0021] The high carbon methacrylate is selected from one or more of tetradecyl methacrylate, hexadecyl methacrylate or octadecyl methacrylate.

[0022] In one embodiment of the present invention, during the mixing process, the temperature is 60-85°C;

[0023] During the reaction, the temperature is 110-130°C and the time is 4-6h.

[0024] In one embodiment of the present invention, the molar ratio of methacrylate to 2-ethyleneoxyethanol is 1-12:1;

[0025] The amount of the solvent used is 4-10 times the total mass of the high carbon methacrylate and 2-ethyleneoxyethanol;

[0026] The amount of the initiator used is 0.8-1.2% of the total mass of the high carbon methacrylate and 2-ethyleneoxyethanol.

[0027] In one embodiment of the present invention, the molar ratio of methacrylate to 2-ethyleneoxyethanol is 6:1.

[0028] In one embodiment of the present invention, the solvent is selected from one of toluene, xylene or dioxane;

[0029] The initiator is selected from one of benzoyl peroxide, ammonium persulfate or azobisisobutyronitrile.

[0030] In one embodiment of the present invention, the post-treatment is vacuuming and passing nitrogen;

[0031] During the polymerization process, the temperature is 120-130°C and the time is 7-8h.

[0032] The second object of the present invention is to provide a binary polymer pour point depressant prepared by the above method.

[0033] The third object of the present invention is to provide a use of a binary polymer lubricating oil pour point depressant in reducing the freezing point of lubricating oil, wherein the binary polymer lubricating oil pour point depressant is mixed with lubricating oil;

[0034] The mass ratio of the binary polymer lubricating oil pour point depressant to the lubricating oil is 1:100-1000.

[0035] In one embodiment of the present invention, the mixing is performed by mixing and stirring followed by ultrasonic dispersion;

[0036] During the mixing process, the temperature is 15-40°C and the ultrasonic dispersion time is 10-20min;

[0037] Preferably, during the mixing process, the temperature is 15-30° C. and the ultrasonic dispersion time is 15 min.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] (1) The binary polymer lubricating oil pour point depressant of the present invention can be well dissolved in lubricating oil, wherein the high carbon methacrylate has good oil solubility due to the presence of long alkyl chains in the molecule, and the alkane side chain has a detailed structure with the paraffin hydrocarbon in the oil product, which can inhibit the wax crystals from forming a three-dimensional network structure through adsorption. Secondly, the ether bond and hydroxyl group in 2-ethyleneoxyethanol are both polar, and the electronegativity of the oxygen atom is greater than that of the carbon atom, so that the electron cloud density on the oxygen atom is higher, and the molecular force between the groups enhances the repulsive force between the wax crystals, thereby producing a good pour point depressing effect.

[0040] (2) The preparation process of the binary polymer lubricating oil pour point depressant of the present invention is simple, the system has stronger complexity, which helps to stabilize the performance of the system, the experimental operation is convenient, and the pour point depressant effect is obvious.

[0041] (3) The raw materials for preparing the binary polymer lubricating oil pour point depressant of the present invention are cheap and easily available, and the synthesis method is simple. It not only has strong oil solubility, but also can effectively improve the low-temperature flow properties of the lubricating oil, and has a good effect in reducing the freezing point, thus providing new possibilities for the use of lubricating oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is the infrared spectrum of tetradecyl methacrylate-2-vinyloxyethanol binary polymer;

[0043] Figure 2 1 is a dipolymer of tetradecyl methacrylate and 2-vinyloxyethanol H NMR spectra. DETAILED DESCRIPTION

[0044] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] The method for measuring the condensation point in the present invention is carried out in accordance with "GB510-83 Determination of Condensation Point of Petroleum Products".

[0046] In the following examples, unless otherwise specified, all reagents used are commercially available reagents; and all detection means and methods used are conventional detection means and methods in the art.

[0047] Example 1

[0048] A method for preparing a binary polymer lubricating oil pour point depressant, comprising the following specific steps:

[0049] (1) In a three-necked flask equipped with a condenser, a water separator, a thermometer and a magnetic stirring device, add 10.33g (0.12mol) of methacrylic acid, 21.44g of tetradecanol (0.1mol), 0.192g of hydroquinone and 50ml of toluene, heat to 60°C to completely dissolve methacrylic acid and tetradecanol in toluene, then quickly add 0.254g of catalyst (p-toluenesulfonic acid) to the three-necked flask, heat to 120°C and react for 7 hours. When the amount of water in the water separator is observed to be equivalent to the theoretical value, that is, the system is a light yellow transparent liquid, the reaction is terminated. After the reaction is completed, the obtained reaction liquid is subjected to reduced pressure distillation to remove the solvent and then alkali washing and water washing: alkali washing is washing with a 5% mass fraction NaOH solution to remove p-toluenesulfonic acid and unreacted methacrylic acid, washing 3 times until the liquid is weakly alkaline; then washing with distilled water until neutral, vacuum drying at 60°C for 5h to obtain tetradecaned methacrylate;

[0050] (2) Add 2.821 g (0.01 mol) of tetradecyl methacrylate, 0.88 g (0.01 mol) of 2-ethyleneoxyethanol and 25 ml of toluene solvent to a three-necked flask equipped with an electric stirrer, a temperature controller, a constant pressure dropping funnel, a reflux condenser and a nitrogen inlet tube, and heat to 60°C to dissolve all the reactants. At the same time, evacuate the three-necked flask for 2 minutes, then pass nitrogen for 2 minutes, and repeat 3 times to remove the air in the reaction system. When the reaction temperature reaches 105°C, slowly add 25 mL of toluene solution containing 0.037 g of benzoyl peroxide (addition takes 30 minutes), and stir under reflux to cause polymerization reaction for 8 hours under the action of the initiator benzoyl peroxide. After the reaction solution was cooled to room temperature, an excess of methanol was added to the reactant to produce a white precipitate. At this time, the supernatant was separated and the precipitate was dissolved in toluene. The above steps were repeated 3 times to remove the benzoyl peroxide in the system. The precipitate was placed in a vacuum drying oven and vacuum dried at 50°C for 5 hours to obtain a fourteen methacrylate-2-vinyloxyethanol binary polymer. The product fourteen methacrylate-2-vinyloxyethanol binary polymer was characterized by nuclear magnetic resonance as follows: Figure 1 and Figure 2 shown.

[0051] Example 2

[0052] The difference from Example 1 is that in step (2), 2.821 g (0.01 mol) of tetradecyl methacrylate is replaced by 8.463 g (0.03 mol) of tetradecyl methacrylate, and 0.058 g of benzoyl peroxide is replaced by 0.0934 g of benzoyl peroxide.

[0053] Example 3

[0054] The difference from Example 1 is that in step (2), 2.821 g (0.01 mol) of tetradecyl methacrylate is replaced by 16.926 g (0.06 mol) of tetradecyl methacrylate, and 0.058 g of benzoyl peroxide is replaced by 0.178 g of benzoyl peroxide.

[0055] Example 4

[0056] The difference from Example 1 is that in step (2), 2.821 g (0.01 mol) of tetradecyl methacrylate is added instead of 25.389 g (0.09 mol) of tetradecyl methacrylate, and 0.058 g of benzoyl peroxide is added instead of 0.263 g of benzoyl peroxide.

[0057] Example 5

[0058] The difference from Example 1 is that in step (2), 2.821 g (0.01 mol) of tetradecyl methacrylate is added instead of 33.852 g (0.12 mol) of tetradecyl methacrylate, and 0.058 g of benzoyl peroxide is added instead of 0.347 g of benzoyl peroxide.

[0059] Comparative Example 1

[0060] The difference from Example 1 is that in step (1), 50 ml of toluene is replaced by 40 ml of acetone, 0.192 g of hydroquinone is replaced by 0.192 g of p-hydroxyanisole, and 0.254 g of p-toluenesulfonic acid is replaced by 0.254 g of formic acid.

[0061] Comparative Example 2

[0062] The difference from Example 1 is that in step (2), 0.01 mol of 2-vinyloxyethanol is replaced by 0.01 mol of allyl glycidyl ether.

[0063] Comparative Example 3

[0064] The difference from Example 1 is that in step (2), 50 ml of toluene is replaced by 50 ml of dioxane, and 0.037 g of benzoyl peroxide is replaced by 0.037 g of potassium persulfate.

[0065] Comparative Example 4

[0066] The difference from Example 1 is that in step (2), 50 ml of toluene is replaced by 5 ml of xylene, and 0.037 g of benzoyl peroxide is replaced by 0.045 g of diacyl peroxide.

[0067] Comparative Example 5

[0068] The difference from Example 1 is that in step (2), 50 ml of toluene is replaced by 100 ml of dioxane, and 0.037 g of benzoyl peroxide is replaced by 0.1 g of diisopropylbenzene peroxide.

[0069] Example 6

[0070] The low temperature flowability test was conducted on the binary copolymer lubricating oil pour point depressants prepared in Examples 1-5 and Comparative Examples 1-5, and the test was conducted according to the method specified in the national standard GB510-83. The operation steps are as follows: the sample (the pour point depressants prepared in Examples 1-5 and Comparative Examples 1-5, respectively) is placed in a test tube, and when cooled to the expected temperature, the test tube is tilted 45° for 1 minute to observe whether the liquid surface moves, and the arithmetic mean of the two repeated results is taken as the pour point of the sample.

[0071] The pour point depressants prepared in Examples 1-5 (named 1#, 2#, 3#, 4#, 5#, respectively) and Comparative Examples 1-5 (named 6#, 7#, 8#, 9#, 10#, respectively) were numbered, added into PAO-6 lubricating oil base oil (Xirunte, Beijing) in different addition amounts, and the freezing point test was carried out (Table 1).

[0072] Table 1 Pour Point Depressing Effects of Pour Point Depressants of Examples 1-5 and Comparative Examples 1-5

[0073]

[0074]

[0075] ΔSP represents the reduction in the freezing point of the lubricating oil after the addition of the pour point depressant relative to the pure lubricating oil. It can be concluded from Table 1 that pour point depressants 1#, 2#, 3#, 4#, and 5# can effectively reduce the freezing point of the lubricating oil, and pour point depressant 3# prepared in Example 3 has the best performance. When the addition amount is 0.5%, ΔSP is 20°C.

[0076] In summary, the preparation method of the binary polymer lubricating oil pour point depressant of the present invention solves the problems of poor effect and poor oil solubility of current lubricating oil pour point depressants, and the introduction of a new monomer 2-ethyleneoxyethanol expands the composition of the pour point depressant, improves the pour point depressing effect, and can reduce the freezing point of the lubricating oil by 8-20°C.

[0077] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the explanation of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A method for preparing a binary polymer lubricating oil pour point depressant, characterized in that: The following steps are involved: The high carbon methacrylate and 2-ethyleneoxyethanol are mixed in a solvent, and an initiator is added after post-treatment to carry out polymerization reaction to obtain a binary polymer lubricating oil pour point depressant: methacrylate tetradecyl-2-ethyleneoxyethanol binary polymer; Wherein, the molar ratio of methacrylate high carbon ester to 2-ethyleneoxyethanol is 1-12:1; The post-treatment is vacuuming and nitrogen passing.

2. The method for preparing a binary polymer lubricating oil pour point depressant according to claim 1, characterized in that: The preparation method of methacrylate high carbon ester is as follows: The polymerization inhibitor, methacrylic acid and higher alcohol are mixed in a solvent, and then a catalyst is added to react to obtain a higher carbon methacrylate.

3. The method for preparing a binary polymer lubricating oil pour point depressant according to claim 2, characterized in that: The molar ratio of methacrylic acid to higher alcohol is 0.8-1.5:1; The amount of solvent added is 1-2 times the total mass of methacrylic acid and higher alcohol; The amount of polymerization inhibitor added is 0.6-0.9% of the total mass of methacrylic acid and higher alcohol; The amount of catalyst added is 1.2-1.8% of the total mass of methacrylic acid and higher alcohol.

4. The method for preparing a binary polymer lubricating oil pour point depressant according to claim 2, characterized in that: The polymerization inhibitor is selected from one of hydroquinone, p-hydroxyanisole or p-benzoquinone; The solvent is selected from one of toluene, xylene or dioxane; The catalyst is selected from one of p-toluenesulfonic acid, oxalic acid or trifluoromethanesulfonic acid; The higher carbon methacrylate is tetradecyl methacrylate.

5. The method for preparing a binary polymer lubricating oil pour point depressant according to claim 2, characterized in that: During the mixing process, the temperature is 60-85°C; During the reaction, the temperature is 110-130°C and the time is 4-6h.

6. The method for preparing a binary polymer lubricating oil pour point depressant according to claim 1, characterized in that: The amount of the solvent used is 4-10 times the total mass of the high carbon methacrylate and 2-ethyleneoxyethanol; The amount of the initiator used is 0.8-1.2% of the total mass of the high carbon methacrylate and 2-ethyleneoxyethanol.

7. The method for preparing a binary polymer lubricating oil pour point depressant according to claim 6, characterized in that: The solvent is selected from one of toluene, xylene or dioxane; The initiator is selected from one of benzoyl peroxide, ammonium persulfate or azobisisobutyronitrile.

8. The method for preparing a binary polymer lubricating oil pour point depressant according to claim 1, characterized in that: During the polymerization process, the temperature is 120-130°C and the time is 7-8h.

9. A binary polymer pour point depressant prepared by the method according to any one of claims 1 to 8.

10. Use of a binary polymer lubricating oil pour point depressant in reducing the freezing point of lubricating oil, characterized in that: Mixing the binary polymer lubricating oil pour point depressant as claimed in claim 9 with lubricating oil; The mass ratio of the binary polymer lubricating oil pour point depressant to the lubricating oil is 1:100-1000.

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