Preparation method of efficient hexafluoropropylene dimer

Abstract

The invention discloses a preparation method of a high-efficiency hexafluoropropylene dimer, and relates to the technical field of hexafluoropropylene dimer preparation. The method comprises the following specific steps: adding a solvent into a reaction kettle with a stirrer, starting stirring, introducing inert gas into the kettle for replacement, and heating the reaction kettle to a set temperature; under the protection of inert gas, slowly introducing a hexafluoropropylene monomer and a resin catalyst into the kettle, keeping stirring, reacting at a set reaction pressure, and cooling to room temperature after the reaction is completed; unreacted hexafluoropropylene monomers and solvents are recovered through a distillation device, products are transferred into a column chromatography device for column chromatography, and the high-purity hexafluoropropylene dimer is obtained. The resin catalyst provided by the invention effectively improves the content of hexafluoropropylene dimer in the product and the yield of the product.

Description

Technical Field

[0001] The invention relates to the technical field of hexafluoropropylene dimer preparation, in particular to a method for preparing a high-efficiency hexafluoropropylene dimer. Background Art

[0002] Hexafluoropropylene dimer, chemical formula C6F 12 , is a synthetic chemical substance with a molecular weight of 300.05. It is a colorless and odorless gas that is insoluble in water at room temperature, but soluble in certain organic solvents. Hexafluoropropylene dimer has excellent chemical stability and heat resistance, so it has a wide range of applications in the field of high-performance materials, such as for the preparation of fluorine-containing polymer materials, fluorine-containing fine chemical products, pharmaceutical intermediates, and fire extinguishing agents.

[0003] Catalyst, a method for preparing hexafluoropropylene dimer (Chinese patent application number: CN202311454214.1). The process of the method is: hexafluoropropylene dimer undergoes gas phase oligomerization reaction in the presence of a catalyst to obtain hexafluoropropylene dimer.

[0004] A method for preparing hexafluoropropylene dimer (Chinese patent application number: CN200610059035.8). The process of the method is: using hexafluoropropylene as a raw material, acetonitrile as a solvent, and potassium thiocyanate as a catalyst, stirring the reaction at an appropriate temperature to prepare the product.

[0005] A method for preparing hexafluoropropylene dimer (Chinese patent application number: CN201810567226.8) The process of the method is: preheating hexafluoropropylene gas is introduced into a reaction container containing an alkyl hexamethylenetetramine fluoride salt shown in formula (IV), and a continuous reaction is carried out under heating and stirring conditions. The reaction product is post-treated to obtain a hexafluoropropylene dimer.

[0006] Controllable polymerization method and device for hexafluoropropylene dimer (Chinese patent application number: CN201811458176.6) The process of this method is: hexafluoropropylene is obtained by gas phase reaction under the catalysis of supported ionic fluoride; the reaction temperature is 150-220°C; the contact time is 0.1-30s; the loading amount of ionic fluoride is 10%-20%; the carrier is activated carbon, aluminum oxide, silicon dioxide or magnesium oxide; the ionic fluoride is AgF, NaF, KF, RbF or CsF.

[0007] Hexafluoropropylene dimer has important applications in the field of special materials due to its excellent chemical stability and heat resistance. However, the traditional synthesis method has problems such as low reaction efficiency, many by-products, and low purity, which limits its application in industrial production. Summary of the invention

[0008] The main purpose of the present invention is to provide a method for preparing a hexafluoropropylene dimer with high efficiency to overcome the deficiencies in the prior art. The method optimizes the reaction conditions by using a specific catalyst and improves the synthesis efficiency and purity of the hexafluoropropylene dimer.

[0009] Another object of the present invention is to provide hexafluoropropylene dimer prepared by the above method.

[0010] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention includes:

[0011] The embodiment of the present invention provides a method for preparing a high-efficiency hexafluoropropylene dimer, and the operation steps are as follows:

[0012] Step 1: Add 800-1200 parts of solvent by mass into a reactor with a stirrer, start stirring, introduce inert gas into the reactor for replacement 3-6 times, and heat the reactor to the set temperature;

[0013] Step 2: Under the protection of inert gas, slowly introduce 85-105 parts of hexafluoropropylene monomer and 0.5-2 parts of resin catalyst into the kettle, keep stirring and react at the set reaction pressure for 2-4 hours, and cool to room temperature after the reaction is completed;

[0014] Step 3: Recover unreacted hexafluoropropylene monomer and solvent through a distillation device, transfer the product to a column chromatography device for column chromatography, collect fractions within the range of 50-65° C., and obtain high-purity hexafluoropropylene dimer.

[0015] In some embodiments of the present invention, the solvent in step 1 is selected from at least one of acetonitrile, dimethyl sulfoxide, sulfolane, tetrahydrofuran or hexafluoroisopropane.

[0016] In some embodiments of the present invention, the inert gas in step 1 and step 2 is selected from at least one of high-purity nitrogen, high-purity argon or high-purity helium.

[0017] In some embodiments of the present invention, the temperature of the reactor in step 1 is 45-65°C.

[0018] In some embodiments of the present invention, the preparation method of the resin catalyst in step 2 is:

[0019] H1: 0.3-2 parts of KF, 0.3-2 parts of CuF2, 3-7 parts of 4-vinyl-1,2-phthalic acid, 520-650 parts of methanol, stirred at 20-35°C for 30-50 minutes;

[0020] H2: Then add 100-150 parts of mercapto resin, 0.03-0.4 parts of aminoporphyrin ruthenium, and 0.3-2 parts of [bmim]OH alkaline ionic liquid, stir at 50-57°C for 50-100 minutes, filter, and dry to obtain a resin catalyst.

[0021] In some embodiments of the present invention, the mercapto resin is selected from one or more of D408 macroporous mercapto resin, D190 macroporous mercapto resin, and LSC-400 mercury removal resin.

[0022] In some embodiments of the present invention, the reaction pressure in step 2 is 0.1-2.0 MPa.

[0023] In some embodiments of the present invention, in step 2, the column chromatography uses silica gel as the stationary phase and n-hexane as the mobile phase.

[0024] In the above-mentioned resin catalyst preparation method, the reaction mechanism mainly involves a thiol-ene addition reaction. This reaction is a click chemistry reaction that is usually carried out quickly under mild conditions to produce highly selective products. In this particular process, an addition reaction occurs between the thiol resin and 4-vinyl-1,2-phthalic acid, and a similar reaction also occurs between the aminoporphyrin ruthenium and 4-vinyl-1,2-phthalic acid. Both reactions can be carried out by nucleophilic addition between the thiol (-SH) group and the carbon-carbon double bond.

[0025] Technical effect:

[0026] The method can improve the reaction yield of hexafluoropropylene dimer, which is usually because the catalyst can effectively promote the reaction between the reactants and reduce the occurrence of side reactions. Due to the high selectivity of the thiol-ene addition reaction, this method may have higher regioselectivity and stereoselectivity in generating the target product, thereby obtaining a purer product. Such addition reactions are usually carried out under relatively mild conditions, which means that the reaction can be carried out at lower temperatures and pressures, reducing energy consumption and equipment requirements. DETAILED DESCRIPTION

[0027] In view of the deficiencies in the prior art, the inventor of this case, after long-term research and extensive practice, was able to propose the technical solution of the present invention. The technical solution, its implementation process and principle, etc. will be further explained as follows.

[0028] Example 1

[0029] A method for preparing a high-efficiency hexafluoropropylene dimer, the operating steps of which are:

[0030] Step 1: Add 800 g of solvent to a reactor with a stirrer, start stirring, introduce inert gas into the reactor for replacement 3 times, and heat the reactor to the set temperature;

[0031] Step 2: Under the protection of inert gas, slowly introduce 85g of hexafluoropropylene monomer and 0.5g of resin catalyst into the kettle, keep stirring and react at the set reaction pressure for 2h, and cool to room temperature after the reaction is completed;

[0032] Step 3: recovering unreacted hexafluoropropylene monomer and solvent through a distillation device, transferring the product to a column chromatography device for column chromatography to obtain high-purity hexafluoropropylene dimer.

[0033] In the step 1, the solvent is selected from acetonitrile.

[0034] In step 1 and step 2, the inert gas is selected from high-purity nitrogen.

[0035] The temperature of the reactor in step 1 is 45°C.

[0036] The preparation method of the resin catalyst in step 2:

[0037] H1: 0.3 g KF, 0.3 g CuF2, 3 g 4-vinyl-1,2-phthalic acid, 520 g methanol, stirred at 20 ° C for 30 minutes;

[0038] H2: Then add 100 g of mercapto resin, 0.03 g of aminoporphyrin ruthenium, and 0.3 g of [bmim]OH alkaline ionic liquid, stir at 50° C. for 50 minutes, filter, and dry to obtain a resin catalyst.

[0039] The mercapto resin is selected from D408 macroporous mercapto resin.

[0040] The reaction pressure in the step 2 is 0.1 MPa.

[0041] In the step 2, the column chromatography uses silica gel as the stationary phase and n-hexane as the mobile phase.

[0042] Example 2

[0043] A method for preparing a high-efficiency hexafluoropropylene dimer, the operating steps of which are:

[0044] Step 1: Add 900 g of solvent to a reactor with a stirrer, start stirring, introduce inert gas into the reactor for replacement 4 times, and heat the reactor to the set temperature;

[0045] Step 2: Under the protection of inert gas, slowly introduce 95g of hexafluoropropylene monomer and 1g of resin catalyst into the kettle, keep stirring and react at the set reaction pressure for 3h, and cool to room temperature after the reaction is completed;

[0046] Step 3: recovering unreacted hexafluoropropylene monomer and solvent through a distillation device, transferring the product to a column chromatography device for column chromatography to obtain high-purity hexafluoropropylene dimer.

[0047] In the step 1, the solvent is selected from dimethyl sulfoxide.

[0048] In step 1 and step 2, the inert gas is selected from high-purity argon.

[0049] The temperature of the reactor in step 1 is 55°C.

[0050] The preparation method of the resin catalyst in step 2:

[0051] H1: 0.8 g KF, 0.8 g CuF2, 4.5 g 4-vinyl-1,2-phthalic acid, 560 g methanol, stirred at 25 ° C for 40 minutes;

[0052] H2: Then add 120 g of mercapto resin, 0.15 g of aminoporphyrin ruthenium, and 0.9 g of [bmim]OH alkaline ionic liquid, stir at 52° C. for 70 minutes, filter, and dry to obtain a resin catalyst.

[0053] The mercapto resin is selected from D190 macroporous mercapto resin.

[0054] The reaction pressure in the step 2 is 0.8 MPa.

[0055] In the step 2, the column chromatography uses silica gel as the stationary phase and n-hexane as the mobile phase.

[0056] Example 3

[0057] A method for preparing a high-efficiency hexafluoropropylene dimer, the operating steps of which are:

[0058] Step 1: Add 1000 g of solvent to a reactor with a stirrer, start stirring, introduce inert gas into the reactor for replacement 5 times, and heat the reactor to the set temperature;

[0059] Step 2: Under the protection of inert gas, slowly introduce 100g hexafluoropropylene monomer and 1.5g resin catalyst into the kettle, keep stirring and react at the set reaction pressure for 3h, and cool to room temperature after the reaction is completed;

[0060] Step 3: recovering unreacted hexafluoropropylene monomer and solvent through a distillation device, transferring the product to a column chromatography device for column chromatography to obtain high-purity hexafluoropropylene dimer.

[0061] In the step 1, the solvent is selected from sulfolane.

[0062] In step 1 and step 2, the inert gas is selected from high-purity argon.

[0063] The temperature of the reactor in step 1 is 55°C.

[0064] The preparation method of the resin catalyst in step 2:

[0065] H1: 1.4 g KF, 1.4 g CuF2, 6 g 4-vinyl-1,2-phthalic acid, 600 g methanol, stirred at 30 ° C for 40 minutes;

[0066] H2: Then add 135 g of mercapto resin, 0.3 g of aminoporphyrin ruthenium, and 1.5 g of [bmim]OH alkaline ionic liquid, stir at 54° C. for 85 minutes, filter, and dry to obtain a resin catalyst.

[0067] The mercapto resin is selected from LSC-400 mercury removal special resin.

[0068] The reaction pressure in step 2 is 1.6 MPa.

[0069] In the step 2, the column chromatography uses silica gel as the stationary phase and n-hexane as the mobile phase.

[0070] Example 4

[0071] A method for preparing a high-efficiency hexafluoropropylene dimer, the operating steps of which are:

[0072] Step 1: Add 1200 g of solvent to a reactor with a stirrer, start stirring, introduce inert gas into the reactor for replacement 6 times, and heat the reactor to the set temperature;

[0073] Step 2: Under the protection of inert gas, slowly introduce 105g of hexafluoropropylene monomer and 2g of resin catalyst into the kettle, keep stirring and react at the set reaction pressure for 4h, and cool to room temperature after the reaction is completed;

[0074] Step 3: recovering unreacted hexafluoropropylene monomer and solvent through a distillation device, transferring the product to a column chromatography device for column chromatography to obtain high-purity hexafluoropropylene dimer.

[0075] In the step 1, the solvent is selected from tetrahydrofuran.

[0076] In step 1 and step 2, the inert gas is selected from high-purity helium.

[0077] The temperature of the reactor in step 1 is 65°C.

[0078] The preparation method of the resin catalyst in step 2:

[0079] H1: 2g KF, 2g CuF2, 7g 4-vinyl-1,2-phthalic acid, 650g methanol, stirred at 35°C for 50 minutes;

[0080] H2: Then add 150 g of mercapto resin, 0.4 g of aminoporphyrin ruthenium, and 2 g of [bmim]OH alkaline ionic liquid, stir at 57° C. for 100 minutes, filter, and dry to obtain a resin catalyst.

[0081] The mercapto resin is selected from D408 macroporous mercapto resin.

[0082] The reaction pressure in step 2 is 2.0 MPa.

[0083] In the step 2, the column chromatography uses silica gel as the stationary phase and n-hexane as the mobile phase.

[0084] Comparative Example 1

[0085] This example is a comparative example of Example 1, and is basically the same as Example 1, except that 4-vinyl-1,2-phthalic acid is not added during the preparation of the resin catalyst.

[0086] Comparative Example 2

[0087] This example is a comparative example of Example 1, which is basically the same as Example 1, except that aminoporphyrin ruthenium is not added during the preparation of the resin catalyst.

[0088] Evaluation of the embodiment:

[0089] In the specific embodiment of the present invention, the content of hexafluoropropylene dimer is determined by gas phase analysis, the capillary column temperature is 150°C, the vaporization chamber temperature is 200°C, the detector temperature is 250°C, high-purity nitrogen is used as the carrier gas, and the detector is a hydrogen flame ionization detector. The product yield is calculated according to the amount of hexafluoropropylene fed.

[0090] The test results are as follows:

[0091] Hexafluoropropylene dimer content % Product yield% Example 1 99.50 87.5 Example 2 99.64 88.1 Example 3 99.87 88.9 Example 4 99.92 89.7 Comparative Example 1 92.31 76.6 Comparative Example 2 93.52 78.9

[0092] It can be seen from the above specific implementation scheme and test results that the resin catalyst proposed in this method effectively increases the content of hexafluoropropylene dimer in the product and the product yield.

[0093] It should be understood that the above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a highly efficient hexafluoropropylene dimer, the operating steps of which are: Step 1: Add 800-1200 parts of solvent by mass into a reactor with a stirrer, start stirring, introduce inert gas into the reactor for replacement 3-6 times, and heat the reactor to the set temperature; Step 2: Under the protection of inert gas, slowly introduce 85-105 parts of hexafluoropropylene monomer and 0.5-2 parts of resin catalyst into the kettle, keep stirring and react at the set reaction pressure for 2-4 hours, and cool to room temperature after the reaction is completed; Step 3: Recover unreacted hexafluoropropylene monomer and solvent through a distillation device, transfer the product to a column chromatography device for column chromatography, collect fractions within the range of 50-65° C., and obtain high-purity hexafluoropropylene dimer.

2. The method for preparing a high-efficiency hexafluoropropylene dimer according to claim 1, characterized in that: In the step 1, the solvent is selected from at least one of acetonitrile, dimethyl sulfoxide, sulfolane, tetrahydrofuran or hexafluoroisopropane.

3. The method for preparing a high-efficiency hexafluoropropylene dimer according to claim 1, characterized in that: In step 1 and step 2, the inert gas is selected from at least one of high-purity nitrogen, high-purity argon or high-purity helium.

4. The method for preparing a high-efficiency hexafluoropropylene dimer according to claim 1, characterized in that: The temperature of the reactor in step 1 is 45-65°C.

5. The method for preparing a high-efficiency hexafluoropropylene dimer according to claim 1, characterized in that: The preparation method of the resin catalyst in step 2 is: H1: 0.3-2 parts of KF, 0.3-2 parts of CuF2, 3-7 parts of 4-vinyl-1,2-phthalic acid, 520-650 parts of methanol, stirred at 20-35°C for 30-50 minutes; H2: Then add 100-150 parts of mercapto resin, 0.03-0.4 parts of aminoporphyrin ruthenium, and 0.3-2 parts of [bmim]OH alkaline ionic liquid, stir at 50-57°C for 50-100 minutes, filter, and dry to obtain a resin catalyst.

6. The method for preparing a high-efficiency hexafluoropropylene dimer according to claim 5, characterized in that: The mercapto resin is selected from one or more of D408 macroporous mercapto resin, D190 macroporous mercapto resin and LSC-400 mercury removal special resin.

7. The method for preparing a high-efficiency hexafluoropropylene dimer according to claim 1, characterized in that: The reaction pressure in step 2 is 0.1-2.0 MPa.

8. The method for preparing a high-efficiency hexafluoropropylene dimer according to claim 1, characterized in that: In the step 2, the column chromatography uses silica gel as the stationary phase and n-hexane as the mobile phase.