Preparation method of polyether lubricating oil

Abstract

The invention discloses a preparation method of polyether lubricating oil, and belongs to the technical field of polymer preparation. The preparation method comprises the following steps: mixing an initiator with linear long-chain alkyl vinyl ether, and reacting to obtain the polyether lubricating oil, the initiator comprises Lewis acid. According to the preparation method of the polyether lubricating oil provided by the invention, an unfavorable chain transfer reaction in a polymerization process is reasonably converted into an available process, the principle is simple, the operation is easy, polymerization can be carried out at room temperature, and the molecular weight (300-43000 Dalton) and molecular weight distribution (1.07-6) of a product can be regulated and controlled. The preparation method of the polyether lubricating oil provided by the invention can efficiently initiate polymerization of alkyl vinyl ether at low cost to obtain low-molecular-weight oligomer, and can be used for preparing practical polyether lubricating oil on a large scale.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer preparation, and in particular relates to a method for preparing polyether lubricating oil. Background Art

[0002] Lubricating oil is widely used in the fields of vehicle transportation, national defense, military industry, aerospace, etc., and has an important impact on the national economy and people's livelihood, economic operation, etc. The vast majority of lubricating oil is base oil, and its quality determines the performance, cost and life of the lubricating oil. The lack of high-quality base oil production technology will lead to a serious imbalance in the base oil structure. Poly α-olefin (PAO) is an extremely important and high-quality Class IV base oil. It has excellent high and low temperature rheology and is very suitable for use in extreme environmental conditions such as plateau and cold areas, aerospace, etc. However, the large-scale production of PAO requires high-quality and continuous large-scale supply of long-chain α-olefins (such as 1-octene, 1-decene, 1-dodecene, etc.). At present, the large-scale production of PAO still has a long way to go. In view of this, finding other alternative polymerization monomers has become a different solution. Alkyl vinyl ether is a class of polymerizable monomers that can be extracted from chemical or biological sources. Due to the energy-donating property of oxygen atoms and the high density of vinyl electron clouds, polymers can be obtained by methods such as cationic polymerization. Due to the characteristics of cationic polymerization, chain transfer reactions are very likely to occur. Under normal temperature or high temperature polymerization conditions, the active center is transferred to the monomer, solvent or impurity, causing the original polymer chain to stop growing and the molecular weight cannot continue to increase. Therefore, when using cationic polymerization to prepare a specific polymer under normal circumstances, researchers are willing to use low temperature (such as -78°C) and other polymerization conditions. Therefore, for a long time, academia and industry have been concerned about how to prepare high molecular weight polyethers, how to control the stereoregularity of monomers, and other issues, and have developed catalytic or initiation systems and active polymerization processes that inhibit chain transfer, but have not fully explored how to positively and actively use chain transfer to prepare corresponding polymer products and apply them. This not only increases the difficulty of preparing corresponding polymer materials, but also increases costs. Summary of the invention

[0003] In order to solve the above problems in the prior art, the present invention provides a method for preparing a polyether lubricating oil.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] The present invention provides a method for preparing a polyether lubricating oil, comprising mixing an initiator with a linear long-chain alkyl vinyl ether to react and obtain the polyether lubricating oil;

[0006] The initiator includes a Lewis acid.

[0007] As a preferred embodiment of the present invention, the linear long-chain alkyl vinyl ether includes one or more of vinyl butyl ether, vinyl n-hexyl ether, vinyl n-octyl ether and vinyl n-dodecyl ether.

[0008] As a preferred embodiment of the present invention, the Lewis acid includes one or more of titanium tetrachloride, zinc dichloride, tin tetrachloride, alkylaluminum chloride, boron trifluoride, tri(pentafluorophenyl)boron, trifluoromethylsulfonic acid, trifluoromethylsulfonate and trifluoromethylsulfonate; the trifluoromethylsulfonate includes one or more of lithium trifluoromethylsulfonate, sodium trifluoromethylsulfonate, potassium trifluoromethylsulfonate, magnesium trifluoromethylsulfonate, calcium trifluoromethylsulfonate, gallium trifluoromethylsulfonate, aluminum trifluoromethylsulfonate, barium trifluoromethylsulfonate, zinc trifluoromethylsulfonate, nickel trifluoromethylsulfonate, cobalt trifluoromethylsulfonate, ferrous trifluoromethylsulfonate, iron trifluoromethylsulfonate, tin trifluoromethylsulfonate, lead trifluoromethylsulfonate, copper trifluoromethylsulfonate, mercuric trifluoromethylsulfonate, manganese trifluoromethylsulfonate, silver trifluoromethylsulfonate, boron trifluoromethylsulfonate, scandium trifluoromethylsulfonate, ammonium trifluoromethylsulfonate and pyridine trifluoromethylsulfonate.

[0009] The above initiators can all be obtained commercially (purchased from reagent manufacturers), and do not need to be synthesized separately, and the cost is low.

[0010] As a preferred embodiment of the present invention, the initiator and the ether monomer are mixed in the following manner: directly mixing the linear long-chain alkyl vinyl ether with the initiator, or adding the initiator into an organic solvent and then adding the linear long-chain alkyl vinyl ether, or adding the linear long-chain alkyl vinyl ether into an organic solvent and then adding the initiator; the organic solvent includes a halogenated hydrocarbon reagent, a benzene reagent or dimethyl sulfoxide.

[0011] As a preferred embodiment of the present invention, the reaction temperature is -78 to 80°C and the reaction time is 0.5 to 48 hours.

[0012] As a preferred embodiment of the present invention, the molar ratio of the initiator to the linear long-chain alkyl vinyl ether is (0.1-10):1000.

[0013] As a preferred embodiment of the present invention, after the reaction is completed, alcohol or ammonia is used to quench the reaction, and then water or methanol is used to wash away the residual initiator, and then the unreacted monomer is removed at room temperature and low pressure or high temperature and normal pressure at 20-25°C and 2-10 kPa or 50-70°C and 90-110 kPa.

[0014] The present invention also provides a polyether lubricating oil prepared according to the above-mentioned preparation method.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] (1) The preparation method of the polyether lubricant provided by the present invention does not increase the difficulty of the relevant preparation process, and reasonably converts the unfavorable chain transfer reaction in the polymerization process into an available process. The alkyl vinyl ethers used in the present invention are all industrial cheap chemical products and are easy to obtain. The cationic polymerization initiator or initiator used in the present invention is low in cost, simple in structure, high in activity, and very convenient to use. These initiators and initiators can initiate polymerization when exposed to air and can be stored in an atmosphere of non-inert gas (such as nitrogen, helium, etc.) (the drug deteriorates by less than 1% by weight after 6 months). The principle of initiating the polymerization of ether monomers through cationic polymerization is simple and easy to operate. The polymerization can be carried out at room temperature, and the molecular weight (300 to 43000 Daltons) and molecular weight distribution (1.07 to 6) of the product can be adjusted. At the same time, it can initiate polymerization in both the bulk and solution states of the monomer, wherein the amount of initiator used in the bulk state can be as low as 0.1% mol (relative to the molar amount of the monomer). After post-treatment, the impurity content is extremely low (less than 0.01 micrograms / gram of product). In summary, the preparation method of the polyether lubricating oil introduced by the present invention can initiate the polymerization of alkyl vinyl ether at low cost and high efficiency to obtain low molecular weight polymers, and can be used to prepare practical polyether lubricating oil on a large scale.

[0017] (2) The present invention addresses the problems of excess vinyl ether monomer production capacity, insufficient utilization, and harsh polymerization conditions, and applies it to the preparation process of lubricating oils from a new perspective, which is expected to make up for the insufficient production capacity of high-end lubricating oils such as PAO. DETAILED DESCRIPTION

[0018] Now, various exemplary embodiments of the present invention are described in detail, and this detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics and embodiments of the present invention. It should be understood that the terms described in the present invention are only for describing specific embodiments and are not used to limit the present invention.

[0019] In addition, for the numerical range in the present invention, it is understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0020] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0021] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0022] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0023] In the following examples, room temperature refers to 23° C., and the raw materials used are all commercially available conventional raw materials, without any special limitation. The following description will not be repeated.

[0024] Example 1

[0025] Weigh aluminum trifluoromethanesulfonate (47.4 mg, 0.1 mmol), put it into a flask, and add a mechanical stirring paddle. Measure vinyl octyl ether (15.6 g, 0.1 mol), slowly drip it into the flask at room temperature, and then stir it at 45°C for 3 hours. Methanol is dripped into the mixture to quench the reaction, and then added to 300 ml of methanol to precipitate and wash away the initiator, etc. at the same time. Remove the solvent at room temperature and 5 kPa, dry the product, and weigh 12.6 g of the product, with a yield of 80.8%.

[0026] Product structure information: H NMR spectrum, 1 H NMR (400 MHz, Chloroform-d), δ = 3.72-3.19 (m, 3H), 1.55 (qd, J = 13.7, 9.3, 6.9 Hz, 2H), 1.44-1.11 (m, 12H), 0.88 (t, J = 6.6 Hz, 3H). Gel permeation chromatography (GPC), weight average molecular weight 6000 Daltons, number average molecular weight 1000 Daltons, molecular weight distribution 6.

[0027] Example 2

[0028] Weigh aluminum trifluoromethanesulfonate (47.4 mg, 0.1 mmol), put it into a flask, add solvent (cyclohexane, 100 ml), and put in a mechanical stirring paddle. Measure vinyl n-octyl ether (15.6 g, 0.1 mol), slowly drip it into the flask at room temperature, and then stir it at 45°C for 3 hours. Diethylamine is dripped into the mixture to quench the reaction, and then added to 300 ml of methanol to precipitate and wash away the initiator at the same time. Remove the solvent at 20°C and 2kPa, dry the product, and weigh 14.8 g of the product, with a yield of 94.9%.

[0029] Product structure information: H NMR spectrum, 1 H NMR (400 MHz, Chloroform-d), δ = 3.72-3.19 (m, 3H), 1.55 (qd, J = 13.7, 9.3, 6.9 Hz, 2H), 1.44-1.11 (m, 12H), 0.88 (t, J = 6.6 Hz, 3H). Gel permeation chromatography (GPC), weight average molecular weight 3000 Daltons, number average molecular weight 1500 Daltons, molecular weight distribution 2.

[0030] Example 3

[0031] Weigh aluminum trifluoromethanesulfonate (47.4 mg, 0.1 mmol), put it into a flask, and add a mechanical stirring paddle. Place the flask in an ice-water bath and maintain it at 0°C. Measure vinyl n-octyl ether (15.6 g, 0.1 mol) and slowly drip it into the flask, then stir it at 0°C for 3 hours. Diethylamine is dripped into the mixture to quench the reaction, and then added to 300 ml of methanol to precipitate and wash away the initiator, etc. at the same time. Remove the solvent at 25°C and 10 kPa, dry the product, and weigh 14.2 g of the product, with a yield of 91%.

[0032] Product structure information: H NMR spectrum, 1 H NMR (400 MHz, Chloroform-d), δ = 3.72-3.19 (m, 3H), 1.55 (qd, J = 13.7, 9.3, 6.9 Hz, 2H), 1.44-1.11 (m, 12H), 0.88 (t, J = 6.6 Hz, 3H). Gel permeation chromatography (GPC), weight average molecular weight 2500 Daltons, number average molecular weight 20 million Daltons, molecular weight distribution 1.25.

[0033] Example 4

[0034] Weigh aluminum trifluoromethanesulfonate (47.4 mg, 0.1 mmol), put it into a flask, and add a mechanical stirring paddle. Place the flask in a low-temperature ethanol bath and maintain it at -20°C. Measure vinyl n-octyl ether (15.6 g, 0.1 mol) and slowly drip it into the flask, then stir at 0°C for 3 hours. Methanol is dripped into the mixture to quench the reaction, and then 300 ml of methanol is added to precipitate and the initiator is washed away at the same time. Remove the solvent at room temperature 5kPa, dry the product, and weigh 14.5 g of the product, with a yield of 92.9%.

[0035] Product structure information: H NMR spectrum, 1 H NMR (400 MHz, Chloroform-d), δ = 3.72-3.19 (m, 3H), 1.55 (qd, J = 13.7, 9.3, 6.9 Hz, 2H), 1.44-1.11 (m, 12H), 0.88 (t, J = 6.6 Hz, 3H). Gel permeation chromatography (GPC), weight average molecular weight 3000 Daltons, number average molecular weight 28 million Daltons, molecular weight distribution 1.07.

[0036] Example 5

[0037] Weigh aluminum trifluoromethanesulfonate (47.4 mg, 0.1 mmol), put it into a flask, and add a mechanical stirring paddle. Measure vinyl n-octyl ether (15.6 g, 0.1 mol), slowly drip it into the flask at room temperature, and then stir it at room temperature for 3 hours. Methanol is dripped into the mixture to quench the reaction, and then 300 ml of methanol is added to precipitate and the initiator is washed away at the same time. Remove the solvent at room temperature and 5 kPa, dry the product, and weigh 12.9 g of the product, with a yield of 82.7%.

[0038] Product structure information: H NMR spectrum, 1 H NMR (400 MHz, Chloroform-d), δ = 3.72-3.19 (m, 3H), 1.55 (qd, J = 13.7, 9.3, 6.9 Hz, 2H), 1.44-1.11 (m, 12H), 0.88 (t, J = 6.6 Hz, 3H). Gel permeation chromatography (GPC), weight average molecular weight 2400 Daltons, number average molecular weight 800 Daltons, molecular weight distribution 3.

[0039] Example 6

[0040] Weigh aluminum trifluoromethanesulfonate (47.4 mg, 0.1 mmol), put it into a flask, and add a mechanical stirring paddle. Place the flask in a low-temperature ethanol bath and maintain it at -78°C. Measure vinyl n-octyl ether (15.6 g, 2.5 mmol), slowly drip it into the flask, and then stir it at 0°C for 8 hours. Methanol is dripped into this mixture to quench the reaction, and then 300 ml of methanol is added to precipitate and the initiator is washed away at the same time. Remove the solvent at 60°C and 101 kPa, dry the product, and weigh 13 grams of the product, with a yield of 83.3%.

[0041] Product structure information: H NMR spectrum, 1 H NMR (400 MHz, Chloroform-d), δ = 3.71-3.18 (m, 3H), 1.54 (qd, J = 13.7, 9.3, 6.9 Hz, 2H), 1.45-1.11 (m, 12H), 0.89 (t, J = 6.6 Hz, 3H). Gel permeation chromatography (GPC), weight average molecular weight 3600 Daltons, number average molecular weight 32 million Daltons, molecular weight distribution 1.12.

[0042] Example 7

[0043] Weigh aluminum trifluoromethanesulfonate (47.4 mg, 0.1 mmol), put it into a flask, add solvent (cyclohexane, 100 ml), and put in a mechanical stirring paddle. Measure vinyl n-octyl ether (15.6 g, 0.1 mol), slowly drip it into the flask at room temperature, and then stir it at 80°C for 0.5 hours. Diethylamine is dripped into the mixture to quench the reaction, and then added to 300 ml of methanol to precipitate and wash away the initiator at the same time. Remove the solvent at 70°C and 90 kPa, dry the product, and weigh 15.3 g of the product, with a yield of 98.1%.

[0044] Product structure information: H NMR spectrum, 1 H NMR (400 MHz, Chloroform-d), δ = 3.73-3.20 (m, 3H), 1.56 (qd, J = 13.7, 9.3, 6.9 Hz, 2H), 1.46-1.11 (m, 12H), 0.88 (t, J = 6.6 Hz, 3H). Gel permeation chromatography (GPC), weight average molecular weight 2800 Daltons, number average molecular weight 1200 Daltons, molecular weight distribution 2.3.

[0045] Other embodiments are listed in table form:

[0046] By changing the reaction conditions (temperature), initiator, etc., the present invention further obtains low molecular weight polyvinyl n-octyl ether, as shown in Table 1:

[0047] Table 1 Preparation of polyether lubricating oil using vinyl octyl ether as monomer (0.1 mol)

[0048]

[0049]

[0050] Note: In the column of “bulk or added solvent”, “bulk” refers to the reaction of single octyl vinyl ether monomer and initiator, while others refer to adding octyl vinyl ether monomer into corresponding solvent and then reacting with initiator.

[0051] The preparation of low molecular weight polyethylene n-dodecyl ether is shown in Table 2:

[0052] Table 2 Preparation of polyether lubricating oil using vinyl n-dodecyl ether as monomer (0.1 mol)

[0053]

[0054]

[0055] The preparation of low molecular weight polyvinyl hexyl ether is shown in Table 3:

[0056] Table 3 Preparation of polyether lubricating oil using vinyl hexyl ether as monomer (0.1 mol)

[0057]

[0058] Effect verification

[0059] As a lubricating oil, the present invention tests the product performance of the corresponding low molecular weight polyether. Taking low molecular weight polyvinyl n-octyl ether as an example, for the convenience of illustration, its name is written as P8VEx (Note: P represents polymer, 8VE represents vinyl n-octyl ether, and x represents the degree of polymerization). The results are shown in Table 4:

[0060] Table 4 Performance test basis and results of polyether lubricating oils prepared in some examples

[0061]

[0062] It has been verified that the number average molecular weight of the polyether lubricating oil obtained in each embodiment of the present invention is 300 to 43000, the molecular weight distribution is 1.07 to 6, and the kinematic viscosity (100°C) is 8 to 220 mm 2 / s, kinematic viscosity (40℃) is 70 to 2900mm 2 / s, viscosity index is 101 to 305, pour point is -65 to -30°C, low temperature dynamic viscosity (-20°C) is 7800 to 330500. It can be seen that the molecular weight and molecular weight distribution of the polyether lubricating oil prepared by the present invention can be controlled, the viscosity can be adjusted accordingly, and the performance is excellent.

[0063] The above description is only a preferred specific implementation manner of the present invention, and the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, and they should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a polyether lubricating oil, characterized in that: The initiator is mixed with the linear long-chain alkyl vinyl ether to react to obtain the polyether lubricating oil; The initiator includes a Lewis acid.

2. The method for preparing a polyether lubricating oil according to claim 1, characterized in that: The linear long-chain alkyl vinyl ether includes one or more of vinyl butyl ether, vinyl n-hexyl ether, vinyl n-octyl ether and vinyl n-dodecyl ether.

3. The method for preparing a polyether lubricating oil according to claim 1, characterized in that: The Lewis acid includes one or more of titanium tetrachloride, zinc dichloride, tin tetrachloride, alkylaluminum chloride, boron trifluoride, tri(pentafluorophenyl)boron, trifluoromethanesulfonic acid, trifluoromethanesulfonic acid esters and trifluoromethanesulfonic acid salts; the trifluoromethanesulfonic acid salt includes one or more of lithium trifluoromethanesulfonate, sodium trifluoromethanesulfonate, potassium trifluoromethanesulfonate, magnesium trifluoromethanesulfonate, calcium trifluoromethanesulfonate, gallium trifluoromethanesulfonate, aluminum trifluoromethanesulfonate, barium trifluoromethanesulfonate, zinc trifluoromethanesulfonate, nickel trifluoromethanesulfonate, cobalt trifluoromethanesulfonate, ferrous trifluoromethanesulfonate, iron trifluoromethanesulfonate, tin trifluoromethanesulfonate, lead trifluoromethanesulfonate, copper trifluoromethanesulfonate, mercuric trifluoromethanesulfonate, manganese trifluoromethanesulfonate, silver trifluoromethanesulfonate, boron trifluoromethanesulfonate, scandium trifluoromethanesulfonate, ammonium trifluoromethanesulfonate and pyridine trifluoromethanesulfonate.

4. The method for preparing a polyether lubricating oil according to claim 1, characterized in that: The reaction temperature is -78 to 80°C and the reaction time is 0.5 to 48 hours.

5. The method for preparing a polyether lubricating oil according to claim 1, characterized in that: The molar ratio of the initiator to the linear long-chain alkyl vinyl ether is (0.1-10):1000.

6. The method for preparing a polyether lubricating oil according to claim 1, characterized in that: After the reaction is completed, alcohol or ammonia is used to quench the reaction, and then water or methanol is used to wash away the residual initiator, and then the unreacted monomer is removed at 20-25° C., 2-10 kPa or 50-70° C., 90-110 kPa.

7. A polyether lubricating oil prepared according to the preparation method according to any one of claims 1 to 6.

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