Polytetrafluoroethylene modification method

Abstract

The invention discloses a modification method of polytetrafluoroethylene, and belongs to the technical field of modification. The invention relates to a modification method of polytetrafluoroethylene, which comprises the following steps: mixing materials containing polytetrafluoroethylene, a modifier, a metal A, a metal salt and a solvent to obtain modified polytetrafluoroethylene, the modifier is a ketone compound; the ketone compound comprises a benzophenone compound and / or a chalcone compound. The method is simple to operate and high in feasibility, and polytetrafluoroethylene can be uniformly modified only by mixing the benzophenone compound (chalcone compound), the metal A, the metal salt and polytetrafluoroethylene; according to the method, the modification efficiency is high, polytetrafluoroethylene, a benzophenone compound (chalcone compound), metal A and metal salt are mixed according to the molar ratio of 0.5: 1: 1: 1, and the modification rate within 30 min can reach 100%; the modification method is novel, and the obtained polytetrafluoroethylene is uniform in modification effect.

Description

Technical Field

[0001] This application relates to a method for modifying polytetrafluoroethylene, belonging to the field of modification technology. Background Technology

[0002] Since American scientist R.S. Plunkett synthesized polytetrafluoroethylene (PTFE), known as the "King of Plastics," in 1938, the research, production, processing, and application of PTFE have experienced tremendous development. Due to its unique properties, it is now widely used in aerospace, petrochemical, machinery, electronics, construction, and textile industries, and is increasingly permeating people's daily lives, becoming an indispensable material for solving many key technologies and improving production levels in modern science, technology, military, and civilian applications.

[0003] Polytetrafluoroethylene (PTFE) is a completely symmetrical and unbranched linear polymer. Fluorine atoms replace hydrogen atoms, and the radius of fluorine atoms is significantly larger than that of hydrogen atoms. This results in stronger van der Waals forces between unbonded atoms in PTFE compared to polyethylene, leading to greater repulsive forces. This causes the carbon-carbon chain to gradually twist from the planar, fully extended, zigzag conformation of polyethylene to the helical conformation of PTFE. This helical conformation surrounds the carbon chain backbone of PTFE, forming a tight, fully "fluorinated" protective layer. This protects the polymer backbone from attack by any external reagents. The carbon-fluorine bond is extremely strong, with a bond energy of 460.2 kJ / mol, far exceeding that of carbon-hydrogen and carbon-carbon bonds. This gives PTFE good thermal stability, chemical inertness, and low surface energy, allowing it to withstand all strong acids (including aqua regia, hydrofluoric acid, concentrated hydrochloric acid, nitric acid, fuming sulfuric acid, organic acids, etc.), strong bases, strong oxidizing agents, and reducing agents, except for molten alkali metals, elemental fluorine, strong fluorinating media (such as chlorine trifluoride), and sodium hydroxide above 300°C.

[0004] Due to its low surface energy and poor surface wettability, polytetrafluoroethylene (PTFE) is difficult to process, such as bonding, ignition, and coating. Therefore, surface modification of PTFE is of great significance. Summary of the Invention

[0005] According to the first aspect of this application, a method for modifying polytetrafluoroethylene (PTFE) is provided. This method can modify PTFE films and powdered PTFE with high modification efficiency and mild reaction conditions.

[0006] A method for modifying polytetrafluoroethylene, comprising the following steps:

[0007] Materials containing polytetrafluoroethylene, modifier, metal A, metal salt, and solvent are mixed to obtain modified polytetrafluoroethylene.

[0008] The modifier is a ketone compound;

[0009] The ketone compounds include benzophenone compounds and / or chalcone compounds.

[0010] Optionally, the benzophenone compound is selected from any one of the following compounds:

[0011]

[0012] Optionally, the chalcone compound is selected from any one of the following compounds:

[0013]

[0014] Optionally, the metal A is selected from at least one of magnesium and calcium.

[0015] Optionally, the metal salt is selected from at least one of lithium chloride, lithium bromide, and lithium iodide.

[0016] Optionally, the polytetrafluoroethylene is selected from at least one of polytetrafluoroethylene film and polytetrafluoroethylene powder.

[0017] Optionally, the solvent includes tetrahydrofuran.

[0018] Optionally, the molar ratio of the modifier, the metal A, and the metal salt is 1-10:1-5:1-10.

[0019] Optionally, the molar ratio of the modifier, the metal A, and the metal salt is 1-5:1-3:1-10.

[0020] The number of moles of the modifier is calculated based on the molecular weight of benzophenone or chalcone compounds.

[0021] Optionally, the molar ratio of the polytetrafluoroethylene to the modifier is 0.1 to 4:1.

[0022] Optionally, the molar ratio of the polytetrafluoroethylene to the modifier is 0.1 to 2:1.

[0023] The number of moles of the modifier is calculated based on the molecular weight of benzophenone or chalcone compounds.

[0024] Optionally, the molar ratio of the polytetrafluoroethylene to the modifier is independently selected from 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1.0:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, etc. 1, 2.0:1, 2.1:1, 2.2:1, 2.3:1, 2.4:1, 2.5:1, 2.6:1, 2.7:1, 2.8:1, 2.9:1, 3.0:1, 3.1:1, 3.2:1, 3.3:1, 3.4:1, 3.5:1, 3.6:1, 3.7:1, 3.8:1, 3.9:1, 4.0:1, any value or a range between any two of them.

[0025] Optionally, the mixing can be carried out under anhydrous and oxygen-free conditions.

[0026] Alternatively, the mixing conditions are as follows:

[0027] The temperature ranges from 10℃ to 80℃.

[0028] The time ranges from 20 minutes to 1440 minutes.

[0029] Optionally, the temperature is independently selected from any value or a range between 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, and 80°C.

[0030] Optionally, the time is independently selected from any value or a range between 20 min, 30 min, 60 min, 80 min, 100 min, 150 min, 200 min, 300 min, 500 min, 700 min, 1000 min, 1100 min, 1200 min, 1300 min, 1400 min, and 1440 min.

[0031] Optionally, the following steps are included:

[0032] S1. Anhydrous and oxygen-free treatment is performed on mixture I containing metal A and metal salt;

[0033] S2. Stir, filter, and wash the material containing the above-mentioned mixture I, polytetrafluoroethylene, and solvent to obtain modified polytetrafluoroethylene.

[0034] Following the reaction, the following steps are also included:

[0035] After removing metal A from the reacted material, the mixture is filtered, and the insoluble substances from the reaction are washed with water and ethanol to obtain the modified polytetrafluoroethylene.

[0036] According to one embodiment of this application, a method for modifying polytetrafluoroethylene is provided, wherein the reagents used in the modification method include benzophenone compounds, chalcone compounds, metal A, and metal salts;

[0037] The benzophenone compounds are selected from any one of the following compounds:

[0038]

[0039] The chalcone compounds are selected from any one of the following compounds:

[0040]

[0041] The metal A is selected from at least one of Mg and Ca;

[0042] The metal salt is selected from at least one of LiCl, LiBr, and LiI.

[0043] Optionally, in the modification method, the molar ratio of the benzophenone compound, metal A, and metal salt is 1-10:1-5:1-10; the molar ratio of the chalcone compound, metal A, and metal salt is 1-10:1-5:1-10.

[0044] Optionally, in the modification method, the molar ratio of the polytetrafluoroethylene to the benzophenone compound is 0.1 to 2:1.

[0045] Specifically, a color change will occur during the reaction.

[0046] The modified polytetrafluoroethylene is obtained by reacting the polytetrafluoroethylene with the above-mentioned mixture of chemicals required for modification.

[0047] This application involves mixing the aforementioned pharmaceuticals with polytetrafluoroethylene (PTFE) materials and reacting them in a single pot at room temperature under anhydrous and oxygen-free conditions. After filtration and washing, the modified PTFE material is obtained. This invention achieves uniform chemical modification of PTFE by breaking some of the high-energy carbon-fluorine bonds with a modifier, leaving a carbonized layer and certain functional groups. The method is simple to operate, has low operating costs, high modification efficiency, and mild reaction conditions, providing a new method for the modification of PTFE and possessing high practical value.

[0048] Optionally, the reaction conditions are as follows: the reaction is carried out under anhydrous conditions, the reaction temperature is 10℃~80℃, and the reaction time is 20min~24h.

[0049] Optionally, the molar ratio of the polytetrafluoroethylene to the benzophenone compound is 0.1 to 2:1.

[0050] Optionally, the molar ratio of the polytetrafluoroethylene to the chalcone compound is 0.1 to 2:1.

[0051] Optionally, the polytetrafluoroethylene may be selected from at least one of polytetrafluoroethylene film and polytetrafluoroethylene powder.

[0052] Optionally, the reaction may involve color changes, with the reaction solution exhibiting different color changes under the action of benzophenone compounds and chalcone compounds.

[0053] Optionally, the mixture may also include a solvent.

[0054] Preferably, the solvent is selected from tetrahydrofuran.

[0055] Optionally, after the reaction, the following step is further included:

[0056] After removing metal A from the reacted material, the mixture is filtered, and the insoluble substances from the reaction are washed with water and ethanol to obtain the modified polytetrafluoroethylene.

[0057] In this application, polytetrafluoroethylene (PTFE) material is modified efficiently. The method is simple to operate, has high modification efficiency, and mild reaction conditions, which can produce modified PTFE with better processing performance.

[0058] Preferably, the method includes: mixing polytetrafluoroethylene with benzophenone compounds, metal A and metal salt in a molar ratio of 0.5:1:1:1, then dissolving the mixture with a solvent, and stirring at room temperature or under heating conditions to carry out the reaction.

[0059] Preferably, the method includes: mixing polytetrafluoroethylene with chalcone compounds, metal A and metal salt in a molar ratio of 0.5:1:1:1, then dissolving the mixture in a solvent, and stirring at room temperature or under heating conditions to carry out the reaction.

[0060] Optionally, after the reaction, the following step is further included:

[0061] After removing metal A from the reacted material, the mixture is filtered, and the insoluble substances from the reaction are washed with water and ethanol to obtain the modified polytetrafluoroethylene.

[0062] Optionally, the reagent used to remove metal A is saturated ammonium chloride.

[0063] Optionally, the rinsing agent for the filter is selected from water and ethanol.

[0064] Optionally, the method includes:

[0065] Step 1: Take molar equivalent amounts of metal A and metal salt and place them into the reactor;

[0066] Step 2: Take the appropriate amount of benzophenone or chalcone compound and mix it with polytetrafluoroethylene in tetrahydrofuran and add it to the reactor;

[0067] Step 3: React under stirring conditions, and then treat for 30 minutes to obtain modified polytetrafluoroethylene.

[0068] This invention utilizes benzophenone and chalcone compounds to react with metal A and metal salts to develop a highly efficient, simple, and easily operable material modification method, providing a practical approach for the modification of polytetrafluoroethylene (PTFE) materials.

[0069] This invention utilizes the reaction of benzophenone or chalcone compounds with metal A and metal salts to develop a highly efficient, simple, and easily operable method for modifying polytetrafluoroethylene (PTFE). This PTFE modification method has high practical value. The method is a one-pot process, simple to operate, highly feasible, and highly efficient in modification. Compared with other existing modification methods, this invention has advantages such as simple post-treatment of the modifier, high safety, and uniform modification effect of the obtained PTFE. By mixing PTFE, benzophenone or chalcone compounds with metal A and metal salts in tetrahydrofuran, and then performing a simple stirring operation at room temperature, well-modified PTFE can be obtained.

[0070] Optionally, the reaction in this application is carried out in solution at room temperature or under heating conditions.

[0071] This invention provides a novel method for chemically modifying polytetrafluoroethylene (PTFE). The chemical modification of PTFE has high commercial value. Therefore, the development of methods for chemically modifying PTFE is of great significance in various application fields. Past methods for chemically modifying PTFE suffer from problems such as highly corrosive modifiers and complex post-processing. This application develops a method for uniformly modifying PTFE by mixing benzophenone compounds (chalcone compounds), metal A, and a metal salt, and using a chemical reaction to break some of the high-energy carbon-fluorine bonds, leaving a carbonized layer and certain functional groups. This method has the advantages of high efficiency, simplicity, strong operability, simple post-processing of the modifier, and high safety. It has significant advantages for subsequent industrialization.

[0072] The beneficial effects that this application can produce include:

[0073] This application provides a method for modifying polytetrafluoroethylene (PTFE). This method is simple to operate and highly feasible. It only requires mixing benzophenone compounds (chalcone compounds), metal A, metal salt, and PTFE to uniformly modify PTFE. This method has high modification efficiency. When PTFE is mixed with benzophenone compounds (chalcone compounds), metal A, and metal salt in a molar ratio of 0.5:1:1:1, the modification rate can reach 100% within 30 minutes. The modification method is novel, and the obtained PTFE has a uniform modification effect. Attached Figure Description

[0074] Figure 1 These are infrared comparison images of the products of Examples 1 and 2 of this invention and unmodified polytetrafluoroethylene.

[0075] Figure 2 The image shows the X-ray diffraction pattern of lithium fluoride formed by the breakage of carbon-fluorine bonds in the product of Example 1 of this invention and its reaction with the metal salt in the modifier.

[0076] Figure 3 This is a comparison diagram of the polytetrafluoroethylene powder before and after modification in this invention.

[0077] Figure 4 This is a comparison image of the polytetrafluoroethylene film before and after modification in this invention. Detailed Implementation

[0078] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0079] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased commercially. The tetrahydrofuran used was of analytical grade.

[0080] Unless otherwise specified, use conventional testing methods or the testing methods recommended by the instrument.

[0081] The instruments used in the examples are: Vertex 70 infrared spectrometer and Miniflex 600 powder diffractometer.

[0082] The room temperature is 20℃~30℃.

[0083] Example 1:

[0084] The benzophenone monomers used in this embodiment are shown in the following formula:

[0085]

[0086] This embodiment includes the following steps:

[0087] (1) Take 1 equivalent of magnesium shavings (i.e., 1.09 mmol, 0.027 g) and lithium chloride (i.e., 1.09 mmol, 0.047 g) and put them into the reaction tube respectively;

[0088] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0089] (3) Take 0.2g (i.e. 1.09mmol) of the above monomer and 0.5mmol (i.e. 0.05g) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to dark blue, and then gradually turns into dark wine red.

[0090] (4) After 30 minutes, process the reaction.

[0091] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0092] Figure 1 The comparison between the infrared spectrum obtained by testing after modification in Example 1 of the present invention and the infrared spectrum of unmodified polytetrafluoroethylene shows that the carbon-fluorine bond breakage on polytetrafluoroethylene causes a decrease in the intensity of the bending vibration peak. Figure 2 This is the powder X-ray diffraction pattern of the modified polytetrafluoroethylene (PTFE) in Example 1. The pattern shows the presence of lithium fluoride signals on the modified PTFE, confirming the breakage of the carbon-fluorine bonds and the reaction of the released fluorine atoms with a metal salt to form lithium fluoride. Therefore, based on... Figure 1-2 It can be seen that this novel chemical modification method has successfully modified polytetrafluoroethylene.

[0093] Example 2:

[0094] The chalcone monomers used in this embodiment are shown in the following formula:

[0095]

[0096] This embodiment includes the following steps:

[0097] (1) Take 0.96 mol (0.024 g) of magnesium shavings and 1 equivalent (0.96 mmol, 0.041 g) of lithium chloride and put them into the reaction tube;

[0098] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0099] (3) Take 0.4g (i.e. 1.92mmol) of the above monomer and 0.05g (i.e. 0.5mmol) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to light yellow, and then gradually turns into dark yellowish-brown.

[0100] (4) After 30 minutes, process the reaction;

[0101] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0102] Figure 1 The comparison between the infrared spectrum obtained by testing after modification in Example 2 of this invention and the infrared spectrum of unmodified polytetrafluoroethylene shows that the carbon-fluorine bond breakage on polytetrafluoroethylene causes a decrease in the intensity of the bending vibration peak.

[0103] Example 3:

[0104] The chalcone monomers used in this embodiment are shown in the following formula:

[0105]

[0106] This embodiment includes the following steps:

[0107] (1) Take magnesium shavings (i.e., 0.98 mmol, 0.024 g) as 1 equivalent and lithium chloride as 2 equivalents (i.e., 1.96 mmol, 0.084 g) and put them into the reaction tube;

[0108] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0109] (3) Take 0.2g (i.e. 0.98mmol) of the above monomer and 0.5mmol (i.e. 0.05g) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to light yellow, and then gradually turns into dark yellowish-brown.

[0110] (4) After 30 minutes, process the reaction;

[0111] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0112] Example 4:

[0113] The benzophenone monomers used in this embodiment are shown in the following formula:

[0114]

[0115] This embodiment includes the following steps:

[0116] (1) Take 1.92 mol (0.024 g) of magnesium shavings and 2 equivalents (1.92 mmol, 0.042 g) of lithium chloride and put them into the reaction tube;

[0117] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0118] (3) Take 0.2g (i.e. 0.96mmol) of the above monomer and 0.5mmol (i.e. 0.05g) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to dark blue, and then gradually turns into dark wine red.

[0119] (4) After 30 minutes, process the reaction;

[0120] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0121] Example 5:

[0122] The chalcone monomers used in this embodiment are shown in the following formula:

[0123]

[0124] This embodiment includes the following steps:

[0125] (1) Take 1 equivalent (0.96 mol, 0.038 g) of metallic calcium and 1 equivalent (0.96 mmol, 0.041 g) of lithium chloride and put them into the reaction tube;

[0126] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0127] (3) Take 0.2g (i.e. 0.96mmol) of the above monomer and 1.5mmol (i.e. 0.15g) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to light yellow, and then gradually turns into dark yellowish-brown.

[0128] (4) After 30 minutes, process the reaction;

[0129] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0130] Example 6:

[0131] The chalcone monomers used in this embodiment are shown in the following formula:

[0132]

[0133] This embodiment includes the following steps:

[0134] (1) Take 1 equivalent (0.96 mmol, 0.024 g) of metallic magnesium and 1 equivalent (0.96 mmol, 0.084 g) of lithium bromide and place them into the reaction tube;

[0135] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0136] (3) Take 0.2g (i.e. 0.96mmol) of the above monomer and 0.48mmol (i.e. 0.048g) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to light yellow, and then gradually turns into dark yellowish-brown.

[0137] (4) After 30 minutes, process the reaction;

[0138] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0139] Example 7:

[0140] The benzophenone monomers used in this embodiment are as follows:

[0141]

[0142] This embodiment includes the following steps:

[0143] (1) Take 1 equivalent of magnesium shavings (i.e., 1.09 mmol, 0.027 g) and 3 equivalents of lithium bromide (i.e., 3.27 mmol, 0.285 g) and put them into the reaction tube;

[0144] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0145] (3) Take 0.2g (i.e. 1.09mmol) of the above monomer and 0.5mmol (i.e. 0.05g) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to dark blue, and then gradually turns into dark wine red.

[0146] (4) After 30 minutes, process the reaction;

[0147] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0148] Example 8:

[0149] The benzophenone monomers used in this embodiment are as follows:

[0150]

[0151] This embodiment includes the following steps:

[0152] (1) Take 1 equivalent of magnesium shavings (i.e., 1.09 mmol, 0.027 g) and 5 equivalents of lithium iodide (i.e., 5.45 mmol, 0.73 g) and put them into the reaction tube;

[0153] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0154] (3) Take 0.2g (i.e. 1.09mmol) of the above monomer and 0.327mmol (i.e. 0.033g) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at 80℃, as the reaction proceeds, the color of the reaction solution changes from colorless to dark blue, and then gradually turns into dark wine red.

[0155] (4) After 30 minutes, process the reaction;

[0156] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0157] Example 9:

[0158] The benzophenone monomers used in this embodiment are shown in the following formula:

[0159]

[0160] This embodiment includes the following steps:

[0161] (1) Take magnesium shavings (i.e., 0.87 mmol, 0.022 g) as 1 equivalent and lithium chloride as 3 equivalents (i.e., 2.61 mmol, 0.111 g) and put them into the reaction tube;

[0162] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0163] (3) Take 0.2g (i.e. 0.87mmol) of the above monomer and 0.87mmol (i.e. 0.087g) of polytetrafluoroethylene and mix them in 4ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to dark blue, and then gradually turns into dark wine red.

[0164] (4) After 30 minutes, process the reaction;

[0165] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0166] Example 10:

[0167] The benzophenone monomers used in this embodiment are shown in the following formula:

[0168]

[0169] This embodiment includes the following steps:

[0170] (1) Take 1 equivalent of magnesium shavings (i.e., 1.67 mmol, 0.041 g) and lithium chloride (i.e., 1.67 mmol, 0.071 g) and put them into the reaction tube respectively;

[0171] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0172] (3) Take 0.3g (i.e. 1.67mmol) of the above monomer and 3.33mmol (i.e. 0.33g) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to dark blue, and then gradually turns into dark wine red.

[0173] (4) After 30 minutes, process the reaction;

[0174] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0175] Example 11:

[0176] The chalcone monomers and olefins used in this embodiment are shown in the following formulas:

[0177]

[0178] This embodiment includes the following steps:

[0179] (1) Take 0.98 mol (0.024 g) of magnesium shavings and 1 equivalent (0.98 mmol, 0.042 g) of lithium chloride and put them into the reaction tube;

[0180] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0181] (3) Take 0.2g (i.e. 0.98mmol) of the above monomer and 0.098mmol (i.e. 0.01g) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to light yellow, and then gradually turns into dark yellowish-brown.

[0182] (4) After 30 minutes, process the reaction;

[0183] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0184] Example 12:

[0185] The chalcone monomers and olefins used in this embodiment are shown in the following formulas:

[0186]

[0187] This embodiment includes the following steps:

[0188] (1) Take 0.76 mol (0.020 g) of magnesium shavings as 1 equivalent and 7 equivalents of lithium chloride (5.32 mmol, 0.225 g) and put them into the reaction tube;

[0189] (2) Perform vacuum blowing and heat treatment to ensure a water-free and oxygen-free environment;

[0190] (3) Take 0.2g (i.e. 0.76mmol) of the above monomer and 0.5mmol (i.e. 0.05g) of polytetrafluoroethylene and mix them in 5ml of tetrahydrofuran solution. Stir and at room temperature, as the reaction proceeds, the color of the reaction solution changes from colorless to light yellow, and then gradually turns into dark yellowish-brown.

[0191] (4) After 30 minutes, process the reaction;

[0192] (5) Remove magnesium shavings with saturated ammonium chloride solution, and filter and wash three times with deionized water and ethanol to obtain modified polytetrafluoroethylene.

[0193] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for modifying polytetrafluoroethylene, characterized in that, Includes the following steps: Materials containing polytetrafluoroethylene, modifier, metal A, metal salt, and solvent are mixed to obtain modified polytetrafluoroethylene. The modifier is a ketone compound; The ketone compounds include benzophenone compounds and / or chalcone compounds.

2. The modification method according to claim 1, characterized in that, The benzophenone compounds are selected from any one of the following compounds:

3. The modification method according to claim 1, characterized in that, The chalcone compounds are selected from any one of the following compounds:

4. The modification method according to claim 1, characterized in that, The metal A is selected from at least one of magnesium and calcium.

5. The modification method according to claim 1, characterized in that, The metal salt is selected from at least one of lithium chloride, lithium bromide, and lithium iodide.

6. The modification method according to claim 1, characterized in that, The polytetrafluoroethylene is selected from at least one of polytetrafluoroethylene film and polytetrafluoroethylene powder; Preferably, the solvent comprises tetrahydrofuran.

7. The modification method according to claim 1, characterized in that, The molar ratio of the modifier, the metal A, and the metal salt is 1-10:1-5:1-10; Preferably, the molar ratio of the modifier, the metal A, and the metal salt is 1-5:1-3:1-10; The number of moles of the modifier is calculated based on the molecular weight of benzophenone or chalcone compounds.

8. The modification method according to claim 1, characterized in that, The molar ratio of the polytetrafluoroethylene to the modifier is 0.1 to 4:1; Preferably, the molar ratio of the polytetrafluoroethylene to the modifier is 0.1 to 2:1; The number of moles of the modifier is calculated based on the molecular weight of benzophenone or chalcone compounds.

9. The modification method according to claim 1, characterized in that, The mixing is carried out under anhydrous and oxygen-free conditions; Preferably, the mixing conditions are as follows: The temperature ranges from 10℃ to 80℃. The time ranges from 20 minutes to 1440 minutes.

10. The modification method according to claim 1, characterized in that, Includes the following steps: S1. Anhydrous and oxygen-free treatment is performed on mixture I containing metal A and metal salt; S2. Stir, filter, and wash the material containing the above-mentioned mixture I, polytetrafluoroethylene, and solvent to obtain modified polytetrafluoroethylene.

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