A preparation method of octafluoro[2,2]paracyclophane

Abstract

The present invention discloses a preparation method of octafluoro[2,2]paracyclophane, which includes: uniformly mixing a parylene N monomer, a polar organic solvent, a photosensitizer and an additive to obtain a mixed solution; performing a light treatment on the mixed solution, and adding a fluorination reagent to the mixed solution to obtain the octafluoro[2,2]paracyclophane. Starting from the N-type parylene monomer, the present invention has few photochemical by-products, high yield and easy purification. Moreover, the N-type parylene monomer has been commercialized and is cheap and easily available, making this preparation method easier to industrialize.

Description

Technical Field

[0001] The present invention relates to the technical field of organic synthesis, and particularly relates to a preparation method of octafluoro[2,2]diparaxylylene. Background Art

[0002] Parylene, with the English name Parylene, is a new type of conformal coating material, which is a polymer of paraxylene. According to different molecular structures, Parylene can be divided into multiple types such as N type, C type, D type, F type, HT type, etc.

[0003] The biggest feature of the Parylene film is that it has no branches, high crystallinity, and an extremely large molecular weight. It can be coated on various shaped surfaces, including sharp edges, and is known as "penetrating everywhere", and can penetrate into cracks and inner surfaces. This nano-coating film prepared by room-temperature deposition under vacuum has a uniform thickness, is dense and pinhole-free, transparent and stress-free, does not contain additives, does not damage the workpiece, and has good electrical insulation and protection. At the same time, it is also a high-purity coating material with chemical inertness and good biocompatibility, and has been recognized by the US FDA for various in-vivo implants. Devices coated with it can improve surface lubricity, biocompatibility, and reliability. Among them, Parylene HT, compared with other Parylenes, the performance of the Parylene HT film is equally excellent or even better: low friction coefficient; excellent water vapor, O2, N2, and CO2 barrier performance; low dielectric constant, dielectric strength, and dielectric loss factor. In addition, compared with other Parylene films, the Parylene HT film has much better thermal stability and ultraviolet stability, which means that the Parylene HT film can fully maintain physical and chemical integrity at high temperatures. At the same time, it has very obvious advantages in terms of resistance to thermal aging, ultraviolet aging, and radiation aging. For example, Parylene HT can withstand high temperatures above 450 degrees Celsius for a long time and can also work stably under ultraviolet light for more than 2000 hours. These excellent properties make Parylene HT have special applications in national defense, aerospace, military and other fields. The synthesis of its monomer AF4 has always been a difficult point, and there are generally problems such as low yield, difficult purification, and high cost.

[0004] Therefore, the existing technology still needs to be further improved and enhanced. Summary of the Invention

[0005] In view of the above deficiencies of the prior art, the present invention provides a preparation method of octafluoro[2,2]diparaxylylene, aiming to solve the problems of low yield, difficult purification, and high cost in the preparation of existing octafluoro[2,2]diparaxylylene.

[0006] The technical solutions adopted by the present invention to solve the above technical problems are as follows:

[0007] A preparation method of octafluoro[2,2]diparaxylylene, which includes:

[0008] Mix the parylene N monomer, polar organic solvent, photosensitizer and additive evenly to obtain a mixed solution;

[0009] Perform light treatment on the mixed solution. During the light treatment process, disperse the fluorination reagent into the mixed solution to obtain the octafluoro[2,2]diparaxylylene.

[0010] The following are the preferred technical solutions of the present invention, but do not limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the purpose and beneficial effects of the present invention can be better achieved and realized.

[0011] As a preferred technical solution, in the preparation method of octafluoro[2,2]diparaxylylene, the polar organic solvent is selected from one or more of acetonitrile, phenylacetonitrile, cyclohexane, cyclohexanol and methanol.

[0012] As a preferred technical solution, in the preparation method of octafluoro[2,2]diparaxylylene, the photosensitizer is selected from one or more of 9-fluorenone, benzophenone, diethoxyacetophenone, tris(2-phenylpyridine)iridium and 2,4,5,6-tetra(diphenylamino)-isophthalonitrile.

[0013] As a preferred technical solution, in the preparation method of octafluoro[2,2]diparaxylylene, the additive is selected from one or more of dibutylhydroxytoluene, phenothiazine, p-benzoquinone and p-phenol.

[0014] As a preferred technical solution, in the preparation method of octafluoro[2,2]diparaxylylene, the fluorination reagent is selected from one or more of 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate), 1-fluoro-4-methyl-1,4-diazoniabicyclo[2.2.2]octane tetrafluoroborate, N-fluorodibenzenesulfonamide, F2 and N2 mixed gas, and N-fluoropyridine trifluoromethanesulfonate.

[0015] As a preferred technical solution, in the preparation method of octafluoro[2,2]diparaxylylene, the wavelength of the light used for the light treatment is 365 - 480 nm.

[0016] As a preferred technical solution, in the preparation method of octafluoro[2,2]diparaxylylene, the step of mixing the parylene N monomer, polar organic solvent, photosensitizer and additive evenly to obtain a mixed solution specifically includes:

[0017] The parylene N monomer, polar organic solvent, photosensitizer, and additive are separately added to a photoreaction vessel, and a magnetic stir bar is added to the photoreaction vessel for magnetic stirring to obtain a mixed solution.

[0018] As a preferred technical solution, in the preparation method of octafluoro[2,2]diparaxylylene, the photoreaction vessel has a transparent cover; the mixed solution is subjected to light treatment, and a fluorination reagent is added to the mixed solution to obtain the octafluoro[2,2]diparaxylylene, which specifically includes:

[0019] At a preset temperature, light is transmitted through the cover to irradiate the mixed solution in the photoreaction vessel;

[0020] The fluorination reagent is added to the photoreaction vessel in multiple portions, and after the reaction, the octafluoro[2,2]diparaxylylene is obtained.

[0021] As a preferred technical solution, in the preparation method of octafluoro[2,2]diparaxylylene, the fluorination reagent is a mixed gas of F2 and N2; the photoreaction vessel has a transparent cover; the mixed solution is subjected to light treatment, and a fluorination reagent is added to the mixed solution to obtain the octafluoro[2,2]diparaxylylene, which specifically includes:

[0022] At a preset temperature, light is transmitted through the cover to irradiate the mixed solution in the photoreaction vessel;

[0023] The mixed gas of F2 and N2 is introduced into the photoreaction vessel in multiple portions through a pipeline, and after the reaction, the octafluoro[2,2]diparaxylylene is obtained.

[0024] As a preferred technical solution, in the preparation method of octafluoro[2,2]diparaxylylene, the preset temperature is 20 - 60 °C.

[0025] Beneficial effects: Compared with the prior art, starting from the N-type parylene monomer, the present invention has fewer photochemical reaction by-products, high yield and easy purification, and the N-type parylene monomer has been commercialized, is cheap and easily available, making the preparation method easier to industrialize. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the preparation route diagram of octafluoro[2,2]diparaxylylene provided by the present invention;

[0027] Figure 2 is the high performance liquid chromatography diagram of octafluoro[2,2]diparaxylylene. DETAILED DESCRIPTION

[0028] The present invention provides a method for preparing octafluoro[2,2]paracyclophane. To make the objectives, technical solutions and effects of the present invention clearer and more definite, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] In addition, the features, operations or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can also be reordered or adjusted in an obvious manner by those skilled in the art. Therefore, the various sequences in the specification and drawings are only for clearly describing a certain embodiment and do not mean that they are necessary sequences, unless it is stated that a certain sequence must be followed. The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the described objects and do not have any sequential or technical meanings. The instruments used are all commercially available products.

[0030] Combined with Figure 1 , the method for preparing octafluoro[2,2]paracyclophane provided by the present invention includes:

[0031] Step 10: Mix the parylene N monomer, polar organic solvent, photosensitizer and additive evenly to obtain a mixed solution.

[0032] Specifically, weigh the parylene N monomer, polar organic solvent, photosensitizer and additive according to the addition ratio, and mix the above materials evenly to form a mixed solution. Among them, the structural formula of the parylene N monomer is: The polar organic solvents include but are not limited to acetonitrile, phenylacetonitrile, cyclohexane, cyclohexanol, methanol, etc.

[0033] The photosensitizers include but are not limited to 9-fluorenone, benzophenone, diethoxyacetophenone, tris(2-phenylpyridine)iridium, 2,4,5,6-tetra(diphenylamino)-isophthalonitrile, etc. The addition amount of the photosensitizer can be 3% of the substrate mass. The additives include but are not limited to dibutylhydroxytoluene (BHT), phenothiazine, p-benzoquinone, p-phenol, etc., and the addition amount can be 0.1% of the substrate mass.

[0034] Step 20: Perform light treatment on the mixed solution, and add a fluorination reagent to the mixed solution to obtain the octafluoro[2,2]paracyclophane.

[0035] Specifically, blue light can be used to irradiate and react with the mixed solution. The wavelength range of the blue light can be 365 - 480 nm, and the temperature range of the irradiation reaction can be 20 - 60 °C. The fluorination reagents include, but are not limited to: 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (Selectfluor S), 1-fluoro-4-methyl-1,4-diazoniabicyclo[2.2.2]octane tetrafluoroborate (Selectfluor II), N-fluorobenzenesulfonimide (NSFI), N-fluoropyridine trifluoromethanesulfonate, F2 / N2 mixed gas (10%), etc. Preferably, a mixed system of Selectfluor S and F2 / N2 gas (10%) is used, and the total addition amount is 8 - 20 times the molar equivalent of the reactants.

[0036] The above technical solutions provided by the present invention will be further explained and illustrated below through specific preparation methods.

[0037] Example 1

[0038] In a photoreaction cup, add 10 g of parylene N monomer, 500 mL of acetonitrile, 0.3 g of photosensitizer 2,4,5,6-tetrakis(diphenylamino)-isophthalonitrile, 0.01 g of phenothiazine, add a magnetic stirrer, turn on the constant temperature magnetic stirrer and stir evenly. Set the temperature to 40 °C, cover with a quartz plate, turn on the planar LED lamp (120 w, 420 nm), and irradiate the reaction solution through the quartz cover plate. Add 160 g of selective fluorination reagent (Selectfluor S) in 8 portions within 4 hours, continue to react for 8 hours after adding. After the reaction is completed, concentrate most of the solvent under reduced pressure, cool to 0 - 10 °C and crystallize for 1 hour, then filter. Add 1000 mL of water to the filter cake, heat to 50 °C and stir for 1 hour. Filter and dry to obtain 14.3 g of crude AF4 product, with a yield of 85%.

[0039] Example 2

[0040] In a photoreaction cup, add 10 g of parylene N monomer, 500 mL of acetonitrile, 0.3 g of photosensitizer 9-fluorenone, 0.02 g of BHT, add a magnetic stirrer, connect the gas pipeline, turn on the constant temperature magnetic stirrer and stir evenly. Set the temperature to 35 °C, cover with a quartz plate, turn on the planar LED lamp (120 w, 420 nm), and irradiate the reaction solution through the quartz cover plate. Open the valve of F2 / N2 gas (10%), slowly introduce F2 / N2 gas, keep the flow rate at about 0.2 L / min, continue to react for 8 hours while introducing gas. After the gas introduction is completed, continue to react for 4 hours, then switch to nitrogen and continue to bubble nitrogen for 1 hour. Concentrate most of the solvent under reduced pressure, cool to 0 - 10 °C and crystallize for 1 hour, then filter. Add 800 mL of water to the filter cake, heat to 50 °C and stir for 1 hour. Filter and dry to obtain 13.5 g of crude AF4 product, with a yield of 79.8%.

[0041] Example 3

[0042] In a photoreaction cup, add 10 g of parylene N monomer, add 500 mL of acetonitrile, 0.3 g of photosensitizer 2,4,5,6-tetra(diphenylamino)-isophthalonitrile, 0.01 g of phenothiazine, add a magnetic stir bar, turn on the constant temperature magnetic stirrer and stir evenly. Set the temperature to 40 °C, cover with a quartz plate, turn on the planar LED lamp (120 w, 420 nm), irradiate the reaction solution through the quartz cover plate, add 16 g of selective fluorinating reagent (Selectfluor S), open the valve of F2 / N2 gas (10%), slowly introduce F2 / N2 gas, keep the flow rate at about 0.2 L / min, continue to react for 8 h while continuously introducing gas. After the gas introduction is completed, continue to react for 4 h, switch to nitrogen and continue to bubble nitrogen for 1 h. Concentrate most of the solvent under reduced pressure, cool to 0 - 10 °C and crystallize for 1 h, then filter. Add 800 mL of water to the filter cake, heat to 50 °C and stir for 1 h. Filter and dry to obtain 15.1 g of crude AF4, with a yield of 89.3%.

[0043] Purification: Add 15 g of crude AF4 to a sublimation flask, cover with a sublimation plate and a lid, and carry out sublimation purification under reduced pressure and heating. Keep at 100 °C and a vacuum pressure of -0.09 Mpa for 20 min, cool, release the gas, remove the initial condensate on the sublimation plate, install the device and continue to heat to 160 °C, keep at a vacuum pressure of -0.09 Mpa for 1.5 h, cool, and remove 13.6 g of high-quality AF4 from the sublimation plate, with a yield of 90.7% and a purity of 99.1%. 1H NMR (200 MHz, CDCl3) δ 7.16 (s, 8H); 19F NMR (376.5 MHz, CDCl3) δ 118.2 (s, 8F). Its spectrum is as Figure 2 shown.

[0044] Example 4

[0045] In a photoreaction cup, add 10 g of parylene N monomer, add 500 mL of cyclohexane, 0.3 g of photosensitizer diethoxyacetophenone, 0.01 g of dibutylhydroxytoluene, add a magnetic stir bar, turn on the constant temperature magnetic stirrer and stir evenly. Set the temperature to 45 °C, cover with a quartz plate, turn on the planar LED lamp (120 w, 450 nm), irradiate the reaction solution through the quartz cover plate, add 160 g of selective fluorinating reagent (Selectfluor II) in 8 portions within 4 hours. After addition, continue to react for 8 h. After the reaction is completed, concentrate most of the solvent under reduced pressure, cool to 8 °C and crystallize for 1 h, then filter. Add 1000 mL of water to the filter cake, heat to 50 °C and stir for 1 h. Filter and dry to obtain 14.1 g of crude AF4, with a yield of 83.8%.

[0046] Example 5

[0047] In a photoreaction cup, add 10 g of parylene N monomer, 500 mL of benzonitrile, 0.3 g of the photosensitizer tris(2-phenylpyridine)iridium, and 0.01 g of p-benzoquinone. Add a magnetic stir bar, turn on the constant-temperature magnetic stirrer to stir evenly, set the temperature to 60 °C, cover with a quartz plate, turn on a planar LED lamp (120 w, 450 nm), and irradiate the reaction solution through the quartz cover plate. Add 160 g of the selective fluorine reagent (Selectfluor II) in 8 portions over 4 hours. After addition, continue the reaction for 8 h. After the reaction is complete, concentrate most of the solvent under reduced pressure, cool to 8 °C, crystallize for 1 h, and filter. Add 1000 mL of water to the filter cake, heat to 50 °C, and stir for 1 h. Filter and dry to obtain 13.2 g of the crude product of AF4, with a yield of 78.5%.

[0048] Example 6

[0049] In a photoreaction cup, add 10 g of parylene N monomer and 500 mL of benzonitrile,

[0050] 0.3 g of the photosensitizer 2,4,5,6-tetra(diphenylamino)isophthalonitrile, and 0.02 g of BHT. Add a magnetic stir bar, connect the gas pipeline, turn on the constant-temperature magnetic stirrer to stir evenly, set the temperature to 40 °C, cover with a quartz plate, turn on a planar LED lamp (120 w, 420 nm), and irradiate the reaction solution through the quartz cover plate. Open the valve of the F2 / N2 gas (10%), slowly introduce the F2 / N2 gas, maintain a flow rate of about 0.3 L / min, continue the reaction while continuously introducing the gas for 8 h. After the gas introduction is complete, continue the reaction for 4 h, switch to nitrogen and continue to bubble nitrogen for 1 h. Concentrate most of the solvent under reduced pressure, cool to 10 °C, crystallize for 1 h, and filter. Add 800 mL of water to the filter cake, heat to 50 °C, and stir for 1 h. Filter and dry to obtain 13.8 g of the crude product of AF4, with a yield of 81.5%.

[0051] Example 7

[0052] In a photoreaction cup, add 10 g of parylene N monomer, 200 mL of benzonitrile, and 300 mL of acetonitrile, 0.3 g of the photosensitizer 2,4,5,6-tetra(diphenylamino)isophthalonitrile, and 0.02 g of BHT. Add a magnetic stir bar, connect the gas pipeline, turn on the constant-temperature magnetic stirrer to stir evenly, set the temperature to 40 °C, cover with a quartz plate, turn on a planar LED lamp (120 w, 420 nm), and irradiate the reaction solution through the quartz cover plate. Open the valve of the F2 / N2 gas (10%), slowly introduce the F2 / N2 gas, maintain a flow rate of about 0.2 L / min, continue the reaction while continuously introducing the gas for 8 h. After the gas introduction is complete, continue the reaction for 4 h, switch to nitrogen and continue to bubble nitrogen for 1 h. Concentrate most of the solvent under reduced pressure, cool to 8 °C, crystallize for 1 h, and filter. Add 1000 mL of water to the filter cake, heat to 50 °C, and stir for 1 h. Filter and dry to obtain 13.6 g of the crude product of AF4, with a yield of 80.3%.

[0053] Example 8

[0054] In a photoreaction cup, add 10 g of parylene N monomer, 200 mL of benzonitrile, 300 mL of acetonitrile, 0.3 g of photosensitizer 2,4,5,6-tetra(diphenylamino)-isophthalonitrile, 0.02 g of phenothiazine. Add a magnetic stir bar, turn on the constant-temperature magnetic stirrer to stir evenly, set the temperature to 40 °C, cover with a quartz plate, turn on a planar LED lamp (120 w, 450 nm), and irradiate the reaction solution through the quartz cover plate. Add 160 g of Selectfluor S in 8 portions within 4 hours, finish adding and continue the reaction for 8 h. After the reaction is completed, concentrate most of the solvent under reduced pressure, cool down to 8 °C for crystallization for 1 h, and filter. Add 1000 mL of water to the filter cake, heat to 50 °C and stir for 1 h. Filter and dry to obtain 14.2 g of crude AF4 product, with a yield of 83.9%.

[0055] Example 9

[0056] In a photoreaction cup, add 10 g of parylene N monomer, 200 mL of benzonitrile, 300 mL of acetonitrile, 0.3 g of photosensitizer 2,4,5,6-tetra(diphenylamino)-isophthalonitrile, 0.02 g of phenothiazine. Add a magnetic stir bar, turn on the constant-temperature magnetic stirrer to stir evenly, set the temperature to 40 °C, cover with a quartz plate, turn on a planar LED lamp (120 w, 450 nm), and irradiate the reaction solution through the quartz cover plate. Add 160 g of N-fluoropyridine trifluoromethanesulfonate in 8 portions within 4 hours, finish adding and continue the reaction for 7 h. After the reaction is completed, concentrate most of the solvent under reduced pressure, cool down to 10 °C for crystallization for 1 h, and filter. Add 800 mL of water to the filter cake, heat to 50 °C and stir for 1 h. Filter and dry to obtain 13.9 g of crude AF4 product, with a yield of 82.2%.

[0057] In summary, the present invention provides a method for preparing octafluoro[2,2]paracyclophane, using N-type parylene monomer as the raw material, irradiating the reaction with blue light, with a wavelength range of 365 - 480 nm, preferably 420 nm. The photosensitizers include 9-fluorenone, benzophenone, diethoxyacetophenone, tris(2-phenylpyridine)iridium, 2,4,5,6-tetra(diphenylamino)-isophthalonitrile, etc.,

[0058] preferably 2,4,5,6-tetra(diphenylamino)-isophthalonitrile. The addition amount is 3% of the substrate mass.

[0059] The fluorination reagents include: 1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (Selectfluor S), 1-fluoro-4-methyl-1,4-diazoniabicyclo[2.2.2]octane tetrafluoroborate (Selectfluor II), N-fluorobenzenesulfonimide (NSF I), N-fluoropyridine trifluoromethanesulfonate, F2 / N2 mixed gas (10%), etc. A mixed system of Selectfluor S and F2 / N2 gas (10%) is preferred. The reaction solvent with a total addition amount of 8-20 times the molar equivalent of the reactants includes acetonitrile, phenylacetonitrile, cyclohexane, cyclohexanol, methanol, etc., and acetonitrile is preferred. The additives include dibutylhydroxytoluene (BHT), phenothiazine, p-benzoquinone, p-phenol, etc., and the addition amount is 0.1% of the substrate mass, and phenothiazine is preferred. The reaction temperature range is 20-60°C, and 40°C is preferred for the reaction. Starting from N-type parylene monomer, the starting materials are commercially available, inexpensive and easily obtained, with few by-products. Only product AF4 and its intermediate are formed. The intermediate can continue to react to obtain the product. The photochemical reaction is green and environmentally friendly, and it is easy to realize industrialization.

[0060] It should be understood that the application of the present invention is not limited to the above examples. For those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present invention.

Claims

1. A method for preparing octafluoro[2,2]dipoly-p-xylene, characterized in that: include: Mixing parylene N monomer, polar organic solvent, photosensitizer and additives uniformly to obtain a mixed solution; The mixed solution is subjected to light treatment, and during the light treatment, a fluorination agent is dispersed into the mixed solution to obtain the octafluoro[2,2]dipoly-p-xylene; The polar organic solvent is selected from one or more of acetonitrile, benzyl cyanide, cyclohexane, cyclohexanol and methanol; The photosensitizer is selected from one or more of 9-fluorenone, benzophenone, diethoxyacetophenone, tris(2-phenylpyridine)iridium and 2,4,5,6-tetrakis(diphenylamino)-isophthalonitrile; The fluorination agent is selected from one or more of 1-chloromethyl-4-fluoro-1,4-diazobicyclo[2.2.2]octane di(tetrafluoroborate), 1-fluoro-4-methyl-1,4-diazabicyclo[2.2.2]octane tetrafluoroborate, N-fluorobisbenzenesulfonamide, a mixed gas of F2 and N2, and N-fluoropyridine trifluoromethanesulfonate; The additive is selected from one or more of butylated hydroxytoluene, phenothiazine, p-benzoquinone and p-phenol; The wavelength of light used in the phototreatment is 420nm or 450nm.

2. The method for preparing octafluoro[2,2]dipoly-p-xylylene according to claim 1, characterized in that: The parylene N monomer, polar organic solvent, photosensitizer and additive are uniformly mixed to obtain a mixed solution, specifically comprising: Parylene N monomer, polar organic solvent, photosensitizer and additive are respectively added into a photoreaction container, and a magnet is added into the photoreaction container for magnetic stirring to obtain a mixed solution.

3. The method for preparing octafluoro[2,2]dipoly-p-xylylene according to claim 2, characterized in that: The photoreaction container has a transparent cover; the mixed solution is subjected to light treatment, and a fluorination agent is added to the mixed solution to obtain the octafluoro[2,2]dipoly-p-xylene, specifically comprising: At a preset temperature, irradiating the mixed solution in the photoreaction container with light through the cover; The fluorination reagent is added into the photoreaction container in multiple times, and the octafluoro[2,2]dipoly-p-xylene is obtained after the reaction.

4. The method for preparing octafluoro[2,2]dipoly-p-xylylene according to claim 2, characterized in that: The fluorination agent is the mixed gas of F2 and N2; the photoreaction container has a transparent cover; the mixed solution is subjected to light treatment, and the fluorination agent is added to the mixed solution to obtain the octafluoro[2,2]dipoly-p-xylene, specifically comprising: At a preset temperature, irradiating the mixed solution in the photoreaction container with light through the cover; The F2 and N2 mixed gas is introduced into the photoreaction container multiple times through a pipeline, and the octafluoro[2,2]dipoly-p-xylene is obtained after the reaction.

5. The method for preparing octafluoro[2,2]dipoly-p-xylylene according to claim 3 or 4, characterized in that: The preset temperature is 20-60°C.

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