Ionization process for perfluorinated ion exchange resins and use thereof

Abstract

The application belongs to the technical field of fluorine-containing polymer material preparation methods, and specifically provides an ionization process for a perfluoro ion exchange resin and application thereof; the perfluoro ion exchange resin contains at least one phosphate ester side group and simultaneously contains one or more other ion exchange groups; hydrolysis reaction is carried out in a hydrolysis solution composed of an alkaline catalyst and a polar organic solution, so that the problem that the CF2-P bond in the phosphate ester group is easily broken in an alkaline solution is solved, and hydrolysis of the phosphate ester and the other ion exchange groups under the same hydrolysis condition is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to a preparation method of fluoropolymer materials, and particularly relates to an ionization process of perfluorinated ion exchange resin and application thereof. BACKGROUND

[0002] Perfluorosulfonic acid ion exchange resin is applied in proton exchange membrane fuel cell due to its special properties, and at present, the working temperature range of fuel cell membrane electrode with perfluorosulfonic acid resin as a key raw material is only 25-80℃, and the lower use temperature range will result in the catalyst layer of the membrane electrode being poisoned in the environment with 10ppm of CO. In order to solve the existing difficulties of the fuel cell membrane electrode, an effective solution is to improve the use temperature of the fuel cell, and therefore, the development of high-temperature proton exchange membrane has become the research focus at home and abroad. A series of research results have been obtained for the problem that the fuel cell is difficult to operate stably above 100℃.

[0003] At present, the research mainly focuses on phosphoric acid doped polymer proton membrane and its fuel cell system, and although this kind of membrane has a simple preparation process and strong high-temperature proton conduction capacity, the phosphoric acid is easy to migrate and separate out, which results in the serious decline of the mechanical properties and chemical properties of the proton membrane, and also cannot meet the actual use demand of the fuel cell. Due to the limitation of the proton conduction and physical and chemical properties of sulfonic acid and phosphoric acid groups, the perfluorosulfonic acid proton membrane is difficult to conduct protons above 100℃, and the phosphoric acid doped membrane is difficult to conduct protons below 100℃, and therefore, the polymer and membrane containing phosphoric acid-sulfonic acid structure can greatly widen the working temperature range of the fuel cell membrane to above 120℃, and break through the low bottleneck of the current fuel cell cross-temperature zone work.

[0004] There are few studies on fluorine-containing polymers containing phosphonic-sulfonic structures, which are basically at the exploratory stage. Currently, the only information available is on binary polymers of perfluorophosphate ester and tetrafluoroethylene, and the related research is more on the polymerization method and the application of resin structure testing. The article Yamabe, Masaaki et al. "Novel phosphonated perfluorocarbon polymers." European Polymer Journal 36 (2000): 1035-1041 introduces that when the perfluorophosphate ester polymer is treated with lye, the CF2-P bond will be completely broken, and the hydrolysis method with acid solution can convert the phosphate ester polymer into phosphoric acid, while the common hydrolysis method of perfluorosulfonyl fluoride resin is to treat it with 5-50% lye to form sulfonate and then perform acidification treatment. The sulfonyl fluoride-SO2F group of perfluorosulfonyl fluoride resin is very stable in acid solution. The perfluoro ion exchange resin precursor containing phosphate and sulfonyl fluoride groups only has ion or proton exchange function after being hydrolyzed into phosphoric acid and sulfonic acid, and can be applied in fuel cell membranes. However, due to the decomposition of perfluorophosphate ester polymer in lye, it is difficult to ionize the perfluoro ion exchange resin precursor containing phosphate and sulfonyl fluoride groups. SUMMARY

[0005] In view of the problem that the ionization of the fluorine-containing ion exchange resin containing phosphate ester in lye will cause decomposition, the application provides an ionization process for perfluoro ion exchange resin, which uses a strong alkaline substance and a solution containing a polar organic solvent as a hydrolysis solution, adjusts the ionization process, realizes the hydrolysis of phosphate ester groups in lye, and does not damage the C-P bond in phosphate ester, and realizes the hydrolysis of phosphate ester, sulfonyl fluoride and / or carboxylate groups at the same time, and simplifies the process.

[0006] To achieve the above object, the technical scheme adopted by the application is:

[0007] An ionization process for perfluoro ion exchange resin, wherein the perfluoro ion exchange resin is subjected to a hydrolysis reaction in a hydrolysis solution.

[0008] The hydrolysis solution comprises an alkaline hydrolysis catalyst and a polar organic solution.

[0009] The perfluoro ion exchange resin is copolymerized from fluorine-containing olefin monomers, perfluorophosphate ester monomers containing phosphate ester groups in side chains, and monomers containing ion / proton exchange groups in side chains.

[0010] The monomer having a side chain containing an ion / proton exchange group includes one or more of a perfluorosulfonyl fluoride monomer having a side chain containing a sulfonyl fluoride group, a perfluorocarboxylate monomer having a side chain containing a carboxylic acid group.

[0011] The fluorine-containing olefin monomer is selected from one or more of tetrafluoroethylene, hexafluoropropylene, fluoroethylene, trifluoropropylene, trifluorochloroethylene, vinylidene fluoride, trifluorostyrene, octafluorobutadiene.

[0012] Preferably, the perfluorophosphate monomer having a side chain containing a phosphate ester group is selected from one or more of formula (I), formula (II):

[0013]

[0014] In formula (I), m is an integer from 0 to 12, preferably m = 0 to 6, more preferably m = 1 to 3;

[0015] n is an integer from 0 to 12, preferably n = 0 to 6, more preferably n = 1 to 3;

[0016] The -R group is C x H 2x+1 wherein x is an integer from 0 to 12, preferably x = 0 to 6, more preferably x = 0 to 3.

[0017] In formula (II), m is an integer from 0 to 6, preferably m = 0 to 3, more preferably m = 0 to 1;

[0018] The -R group is C x H 2x+1 wherein x is an integer from 0 to 12, preferably x = 0 to 6, more preferably x = 0 to 3.

[0019] Preferably, the perfluorosulfonyl fluoride monomer having a side chain containing a sulfonyl fluoride group is selected from a monomer having the structural formula of formula (III):

[0020]

[0021] In formula (III), m is an integer from 0 to 6, preferably m = 0 to 3, more preferably m = 0 to 1;

[0022] n is an integer from 0 to 12, preferably n = 0 to 8, more preferably n = 0 to 4.

[0023] Preferably, the perfluorocarboxylate monomer having a side chain containing a carboxylic acid ester group is selected from a monomer having the structural formula of formula (IV):

[0024]

[0025] In formula (IV), m is an integer from 0 to 12, preferably m = 0-6, more preferably m = 1-3;

[0026] n is an integer from 0 to 12, preferably n = 0-8, more preferably n = 0-4;

[0027] The -R group is C x H 2x+1 wherein x is an integer from 0 to 12, preferably x = 0-6, more preferably x = 0-3.

[0028] Preferably, the basic hydrolysis catalyst is selected from one or more of sodium hydroxide, potassium hydroxide, lithium hydroxide, cesium hydroxide, rubidium hydroxide, aqueous ammonia, triethylamine, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, lithium carbonate, lithium bicarbonate, ammonium carbonate.

[0029] Preferably, the polar organic solvent is one or more of a mixture of methanol, ethanol, ethylene glycol, n-propanol, isopropanol, n-butanol, acetone, glycerol, butanediol, propylene glycol, N-methyl pyrrolidone (NMP), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMAc).

[0030] Preferably, the ionization process for the perfluorinated ion exchange resin comprises the following steps:

[0031] (1) adding the perfluorinated ion exchange resin to the hydrolysis solution to obtain a resin-hydrolysis solution mixture;

[0032] (2) heating and stirring the resin-hydrolysis solution mixture to perform the hydrolysis reaction;

[0033] (3) after cooling the product obtained in step (2) to room temperature, removing impurities and acidifying to obtain a perfluorinated ion exchange resin containing phosphoric acid, sulfonic acid and / or carboxylic acid.

[0034] Preferably, the molar ratio of the basic hydrolysis catalyst to the ion exchange group in the perfluorinated ion exchange resin is (2-10):1. Too high a content of the basic hydrolysis catalyst will cause the C-P bond to break.

[0035] Preferably, the perfluorinated ion exchange resin is 0.5-50%, preferably 0.5-30%, of the total mass of the polar organic solution and the perfluorosulfonic acid exchange resin.

[0036] Preferably, the mass percentage of the polar organic solvent in the polar organic solution is 30-100%. Preferably, the hydrolysis temperature is 60-280℃, and the hydrolysis time is 1-96h.

[0037] In the present application, the room temperature is 10-30℃.

[0038] The acidizing mode is acid liquid acidizing or hydrogen type ion exchange resin exchange;

[0039] The acid liquid is a strong acid or a strong acid mixture;

[0040] Preferably, the strong acid includes nitric acid, sulfuric acid, nitric acid.

[0041] The application also provides the application of the above ionization process, and the application fields include the preparation of proton exchange membrane fuel cell electrodes and electrolyte films, especially high-temperature-resistant proton battery films, vanadium flow battery films, ion membrane production and repair, polytetrafluoroethylene surface hydrophilic treatment, catalyst coating, electrochemical sensor production, electrolytic devices, electrochemical devices, and electrodialysis devices.

[0042] The application hydrolyzes the perfluoro ion exchange resin containing phosphate, sulfonyl fluoride and / or carboxylate in a hydrolysis solution composed of alkaline hydrolysis catalyst and polar organic solution, and the perfluoro ion exchange resin containing phosphate, sulfonyl fluoride and / or carboxylate is simultaneously hydrolyzed at a certain solid content, temperature and constant temperature time, that is, the sulfonyl fluoride is hydrolyzed into sulfonate, the carboxylate is hydrolyzed into carboxylic acid, and the phosphate is hydrolyzed into phosphate or phosphoric acid.

[0043] Advantages

[0044] 1. The application hydrolyzes in a hydrolysis solution composed of alkaline hydrolysis catalyst and polar organic solution, wherein the alkaline hydrolysis catalyst is used for hydrolyzing the sulfonyl fluoride group / carboxylate group, and the polar organic solution is used for hydrolyzing the phosphate group, so as to simultaneously hydrolyze the perfluoro ion exchange resin containing phosphate, sulfonyl fluoride and / or carboxylate.

[0045] 2. The hydrolysis of the sulfonyl fluoride / carboxylate group in the prior art is generally carried out in a high-concentration lye, and when the concentration is reduced, the hydrolysis reaction process of the sulfonyl fluoride / carboxylate group is slow, and the application adopts the polar organic solution to promote the rapid hydrolysis of the sulfonyl fluoride / carboxylate group while realizing the hydrolysis of the phosphate. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 It is the standard nuclear magnetic phosphorus spectrum of the phosphate monomer in Example 1.

[0047] Figure 2 It is the nuclear magnetic fluorine spectrum of the perfluoro ion exchange resin containing phosphate and sulfonyl fluoride groups before hydrolysis in Example 1.

[0048] Figure 3 It is the nuclear magnetic phosphorus spectrum of the perfluoro ion exchange resin containing phosphate and sulfonyl fluoride groups before hydrolysis in Example 1.

[0049] Figure 4NMR spectrum of the phosphonic acid and sulfonic acid group-containing perfluorinated ion exchange resin after hydrolysis in Example 1;

[0050] Figure 5 NMR spectrum of the perfluorinated ion exchange resin after hydrolysis in Comparative Example 1;

[0051] Figure 6 NMR spectrum of the perfluorinated ion exchange resin after hydrolysis in Comparative Example 2. DETAILED DESCRIPTION

[0052] The present application is described in more detail below by way of examples, but the present application is not limited to the examples.

[0053] The perfluorinated ion exchange resin in the following examples can be prepared according to the known techniques in the art, and the preparation method can be emulsion polymerization, solution polymerization, bulk polymerization, etc.

[0054] Example 1

[0055] (1) 350 g of the phosphonic acid and sulfonyl fluoride group-containing perfluorinated ion exchange resin EW885 was added into a 5 L high-pressure autoclave, then a mixed solution of water and methanol with a mass ratio of 30:70 3150 g and 49.80 g of lithium hydroxide were added into the 5 L high-pressure autoclave and stirred for 10 min until the lithium hydroxide was completely dissolved.

[0056] The perfluorinated ion exchange resin is copolymerized from a fluorine-containing olefin monomer, a perfluorophosphonate monomer with a side chain containing a phosphonic acid group, and a perfluorosulfonyl fluoride monomer with a side chain containing a sulfonyl fluoride group.

[0057] The fluorine-containing olefin monomer is tetrafluoroethylene; the perfluorophosphonate monomer with a side chain containing a phosphonic acid group has the following structural formula:

[0058]

[0059] In formula (I), m is 0, n is 2, and the -R group is C2H5;

[0060] The perfluorosulfonyl fluoride monomer with a side chain containing a sulfonyl fluoride group has the following structural formula:

[0061]

[0062] In formula (III), m is 1; n is 2.

[0063] (2) After the high-pressure autoclave was sealed, it was stirred at 25°C for 30 min, then the temperature in the autoclave was raised to 200°C, and the stirring was maintained at 200°C for 6 h at a rotation speed of 200 rpm;

[0064] (3) Subsequently, the reactor was cooled to 25°C, and the solution in the reactor was filtered through a PTFE membrane with a pore size of 1 micrometer.

[0065] (4) The filtered solution is ion exchanged in a glass exchange column containing hydrogen-type cation exchange resin to obtain an ion exchange resin containing both phosphoric acid and sulfonic acid.

[0066] like Figure 1 The image shows the standard NMR spectrum of phosphorus for phosphate ester monomers. As can be seen from the figure, the three phosphorus signal peaks are at -0.28 ppm, -0.7 ppm, and -1.0 ppm. However, as... Figure 3 The NMR phosphorus spectrum of the hydrolyzed perfluorinated ion exchange resin containing phosphate ester and sulfonyl fluoride groups shows that after hydrolysis, the three phosphorus signal peaks (-0.28ppm, -0.7ppm, -1.0ppm) near 0-1ppm are very strong, indicating that the hydrolysis method in this embodiment did not destroy the CP bonds of the perfluorinated ion exchange resin.

[0067] The NMR fluorine spectra of perfluorinated ion exchange resins containing phosphate ester and sulfonyl fluoride groups before and after hydrolysis are shown below. Figure 2 , 4 As shown in the figure, the NMR fluorine spectrum of the perfluorinated ion exchange resin before and after hydrolysis remains essentially unchanged.

[0068] Example 2

[0069] (1) Add 175g of EW400 fluorinated ion exchange resin containing phosphate and carboxylic acid groups to a 5L high-temperature and high-pressure reactor, then add 3325g of pure ethanol and 80.9g of lithium carbonate to the 5L high-temperature and high-pressure reactor and stir for 30min until the lithium carbonate is completely dissolved.

[0070] The perfluorinated ion exchange resin is copolymerized from fluorinated olefin monomers, perfluorophosphate monomers with phosphate ester groups on the side chains, and perfluorosulfonyl fluoride monomers with sulfonyl fluoride groups on the side chains.

[0071] The fluorinated olefin monomer is tetrafluoroethylene; the perfluorophosphate monomer with phosphate ester groups in its side chain has the following structural formula:

[0072]

[0073] In formula (I), m is 1; n is 2; and the -R group is C2H5.

[0074] The structural formula of the perfluorosulfonyl fluoride monomer containing sulfonyl fluoride groups in its side chain is as follows:

[0075]

[0076] In equation (III), m is 1 and n is 2.

[0077] (2) After sealing the high-pressure high-temperature reactor, stir at 25°C for 30 min, then raise the temperature of the reactor to 150°C, and keep stirring at 150°C for 20 h at a speed of 250 rpm;

[0078] (3) After the reactor is cooled to 25°C, filter the solution in the reactor through a PP membrane with a pore size of 2 microns;

[0079] (4) After the filtered solution is exchanged in a chromatographic column containing hydrogen-type cation exchange resin, an ion exchange resin containing both phosphoric acid and carboxylic acid is obtained.

[0080] Example 3

[0081] (1) Put 525 g of fluorine-containing ion exchange resin containing phosphoric ester and sulfonyl fluoride groups with EW750 into a 2L high-temperature high-pressure reactor, then add a mixed solution of water and n-propanol with a mass ratio of 50:50 2975 g and 78.4 g of sodium hydroxide into the 2L high-temperature high-pressure reactor and stir for 10 min until the sodium hydroxide is completely dissolved.

[0082] The perfluorinated ion exchange resin is copolymerized from fluorine-containing olefin monomers, perfluorophosphate ester monomers with side chains containing phosphate groups, and perfluorosulfonyl fluoride monomers with side chains containing sulfonyl fluoride groups.

[0083] The fluorine-containing olefin monomer is tetrafluoroethylene; the perfluorophosphate ester monomer with side chains containing phosphate groups has the following structural formula:

[0084]

[0085] In formula (I), m is 0; n is 2; -R group is C2H5;

[0086] The perfluorosulfonyl fluoride monomer with side chains containing sulfonyl fluoride groups has the following structural formula:

[0087]

[0088] In formula (III), m is 0; n is 4. (2) After sealing the high-pressure high-temperature reactor, stir at 25°C for 30 min, then raise the temperature of the reactor to 230°C, and keep stirring at 230°C for 10 h at a speed of 350 rpm.

[0089] (3) After the constant temperature timer is finished, the reactor is cooled to 25°C, then the reactor is opened, and the solution in the reactor is separated from the insoluble material by a centrifuge at 5000 rpm;

[0090] (4) After the supernatant after centrifugation is exchanged in a chromatographic column containing hydrogen-type cation exchange resin, an ion exchange resin containing both phosphoric acid and sulfonic acid is obtained.

[0091] Example 4

[0092] (1) 87.5 g of EW1000 fluorine-containing ion exchange resin containing phosphoric acid ester and sulfonyl fluoride groups was added into a 5 L high-temperature high-pressure reaction kettle, then a mixed solution of water and n-propanol with a mass ratio of 40:60 3412.5 g and 29.4 g of potassium hydroxide were added into the 5 L high-temperature high-pressure reaction kettle and stirred for 10 min until the potassium hydroxide was completely dissolved.

[0093] The perfluorinated ion exchange resin is copolymerized from fluorine-containing olefin monomers, perfluorophosphate monomers with side chains containing phosphoric acid ester groups, and perfluorosulfonyl fluoride monomers with side chains containing sulfonyl fluoride groups.

[0094] The fluorine-containing olefin monomer is tetrafluoroethylene; the perfluorophosphate monomer with side chains containing phosphoric acid ester groups has the structural formula:

[0095]

[0096] In formula (I), m is 2; -R group is CH3;

[0097] The perfluorosulfonyl fluoride monomer with side chains containing sulfonyl fluoride groups has the structural formula:

[0098]

[0099] In formula (III), m is 0; n is 2.

[0100] (2) After the high-pressure high-temperature reaction kettle was sealed, it was stirred at 25°C for 30 min, then the kettle temperature was raised to 80°C, and kept at 80°C for 24 h, with a rotation speed of 350 rpm.

[0101] (3) After the constant temperature time ended, the kettle was cooled to 25°C, then the kettle was opened, and the lower insoluble material was separated from the solution in the kettle by a centrifuge at 5000 rpm;

[0102] (4) After the supernatant after centrifugation was added with 20 wt% nitric acid solution, ultrafiltration concentration was performed, and after 5 cycles, the potassium ion content in the solution was less than 10 ppm, then the acidification was completed, and the ion exchange resin containing phosphoric acid and sulfonic acid was obtained.

[0103] Example 5

[0104] (1) 175 g of EW800 fluorine-containing ion exchange resin containing phosphoric acid ester and carboxylate groups was added into a 5 L high-temperature high-pressure reaction kettle, then 3325 g of dimethyl sulfoxide (DMSO) and 27.6 g of lithium hydroxide with a mass ratio of 50:50 were added into the 5 L high-temperature high-pressure reaction kettle and stirred for 30 min until the lithium hydroxide was completely dissolved.

[0105] The perfluoro ion exchange resin is copolymerized from a fluorine-containing olefin monomer, a perfluoro phosphate ester monomer with a side chain containing a phosphate ester group, and a perfluoro carboxylic ester monomer with a side chain containing a carboxylic ester group.

[0106] The fluorine-containing olefin monomer is tetrafluoroethylene; the perfluoro phosphate ester monomer with a side chain containing a phosphate ester group has a structural formula of:

[0107]

[0108] In formula (I), m is 0; n is 2; -R group is CH3;

[0109] The perfluoro carboxylic ester monomer with a side chain containing a carboxylic ester group has a structural formula of:

[0110]

[0111] In formula (IV), m is 1; n is 2; -R group is CH3.(2) After the high-pressure and high-temperature reaction kettle is sealed well, the reaction kettle is stirred at 25℃ for 30 min, then the kettle is heated to 150℃, and kept at 150℃ for 10 h, with a rotation speed of 250 rpm;

[0112] (3) After the constant temperature time ends, the reaction kettle is cooled to 25℃, then the kettle is opened, and the solution in the kettle is filtered through a 2-μm PP membrane filter to obtain a perfluoro ion exchange resin solution containing both phosphoric acid and carboxylic acid;

[0113] (4) The 2-μm PP membrane filter solution is exchanged in a hydrogen-type cation exchange resin chromatographic column to obtain an ion exchange resin containing both phosphoric acid and carboxylic acid.

[0114] Example 6

[0115] (1) 105 g of EW950 fluorine-containing ion exchange resin containing phosphate ester and sulfonyl fluoride groups is added to a 5-L high-temperature and high-pressure reaction kettle, then 3325 g of acetone and 51.6 g of 30 wt% ammonia water are added to the 5-L high-temperature and high-pressure reaction kettle.

[0116] The perfluoro ion exchange resin is copolymerized from a fluorine-containing olefin monomer, a perfluoro phosphate ester monomer with a side chain containing a phosphate ester group, and a perfluoro sulfonyl fluoride monomer with a side chain containing a sulfonyl fluoride group.

[0117] The fluorine-containing olefin monomer is tetrafluoroethylene; the perfluoro phosphate ester monomer with a side chain containing a phosphate ester group has a structural formula of:

[0118]

[0119] In formula (I), m is 2; -R group is C2H5;

[0120] The structure of the perfluoro sulfuryl fluoride monomer with sulfuryl fluoride group in the side chain is:

[0121]

[0122] In formula (III), m is 0; n is 2.

[0123] (2) After the high-pressure and high-temperature reactor was sealed, the reactor was stirred at 25℃ for 30 min, and then the temperature in the reactor was raised to 260℃, and the temperature was kept at 260℃ for 8 h at a rotation speed of 200 rpm.

[0124] (3) After the constant temperature time ended, the reactor was cooled to 25℃, and then the reactor was opened, and the solution in the reactor was filtered through a 2-μm PP membrane;

[0125] (4) After the filtered fluorine-containing ion exchange resin was replaced 10 times in a 10wt% sulfuric acid solution at 65℃, the acidification was completed when the lithium ion content in the resin was less than 15 ppm, and a fluorine-containing ion exchange resin containing phosphoric acid and sulfonic acid was obtained.

[0126] Example 7

[0127] (1) 105 g of the fluorine-containing ion exchange resin containing phosphoric ester, carboxylic ester and sulfuryl fluoride group of EW1050 was added into a 5L high-temperature and high-pressure reactor, and then 3325 g of methanol and 51.6 g of 30% ammonia water were added into the 5L high-temperature and high-pressure reactor.

[0128] The perfluoro ion exchange resin is copolymerized from fluorine-containing olefin monomer, perfluoro phosphate ester monomer with phosphoric ester group in the side chain, perfluoro sulfuryl fluoride monomer with sulfuryl fluoride group in the side chain, and perfluoro carboxylic ester monomer with carboxylic ester group in the side chain.

[0129] The fluorine-containing olefin monomer is tetrafluoroethylene; the structure of the perfluoro phosphate ester monomer with phosphoric ester group in the side chain is:

[0130]

[0131] In formula (I), m is 0; n is 2; -R group is C2H5;

[0132] The structure of the perfluoro sulfuryl fluoride monomer with sulfuryl fluoride group in the side chain is:

[0133]

[0134] In formula (III), m is 0; n is 4;

[0135] The structure of the perfluoro carboxylic ester monomer with carboxylic ester group in the side chain is:

[0136]

[0137] In formula (IV), m is 1; n is 2; -R group is CH3.

[0138] (2) After sealing the high-pressure high-temperature reactor, stirring at 25°C for 30 min, the reactor was heated to an internal temperature of 260°C, and kept at 260°C for 8 h at a rotation speed of 200 rpm.

[0139] (3) After the constant temperature timer was stopped, the reactor was cooled to 25°C, and then the reactor was opened. The solution in the reactor was filtered through a 2-μm PP membrane.

[0140] (4) After the filtered fluorine-containing ion exchange resin was replaced 10 times in a 10wt% sulfuric acid solution at 65°C, the acidification was completed when the lithium ion content in the resin was less than 15 ppm, to obtain a fluorine-containing ion exchange resin containing phosphoric acid and sulfonic acid.

[0141] Comparative Example 1

[0142] The hydrolysis solution used in this comparative example was a 20wt% KOH aqueous solution containing 5wt% methanol. After treatment at 85°C for 72 h, the sample was tested by nuclear magnetic phosphorus spectrum. As shown in Figure 5 acidification was performed using 12wt% hydrochloric acid, deionized water was used for washing, and drying was performed to obtain a perfluorinated ion exchange resin. The remaining steps were the same as in Example 1.

[0143] From Figure 5 it can be seen that the same concentration of perfluorinated ion exchange resin solution was tested by nuclear magnetic phosphorus spectrum, and the phosphorus signal peak near 0 ppm was greatly weakened, indicating that a large number of C-P bonds were broken. This is because: in order to rapidly hydrolyze the sulfonyl fluoride group and increase the alkaline solution concentration, thereby breaking the C-P bond. In this comparative example, due to the low content of methanol, the C-P bond cannot be effectively protected, resulting in a large number of C-P bond breakage.

[0144] Comparative Example 2

[0145] The hydrolysis solution used in this comparative example was a 20wt% LiOH aqueous solution. After treatment at 200°C for 6 h, the sample was tested by nuclear magnetic phosphorus spectrum. As shown in Figure 6 acidification was performed using 10wt% nitric acid, deionized water was used for washing, and drying was performed to obtain a perfluorinated ion exchange resin. The remaining steps were the same as in Example 1.

[0146] From Figure 6As can be seen from the NMR phosphorus spectrum of the perfluorinated ion exchange resin solution of the same concentration, the phosphorus signal peak near 0 ppm disappears, indicating that the CP bond in the resin has been completely broken. This is because the lithium hydroxide content in this comparative example is too high in order to hydrolyze the sulfonyl fluoride group, which promotes the breaking of CP.

[0147] Table 1 shows the ion exchange capacity of each embodiment and comparative example. The ion exchange capacity was tested according to GB / T30296 2013. As shown in Table 1, the ion exchange capacity of each embodiment and comparative example before and after ionization treatment are respectively. It can be seen from the table that the ion exchange capacity of the present invention is slightly reduced, while the ionization method of the comparative example has a significantly reduced exchange capacity. However, there is still an exchange capacity of about 0.45 mmol / g, which mainly comes from the sulfonic acid group. The phosphate group in the comparative example is basically completely decomposed.

[0148] Table 1. Ion exchange capacities of Examples 1-7 and Comparative Examples 1-2

[0149]

Claims

1. An ionization process for perfluorinated ion exchange resin, characterized in that, The perfluorinated ion exchange resin is used in the hydrolysis reaction of the hydrolysis solution; The hydrolysis solution comprises a basic hydrolysis catalyst and a polar organic solution; The perfluorinated ion exchange resin is copolymerized from a fluorine-containing olefin monomer, a perfluorophosphate monomer with a side chain containing a phosphate group, and a monomer with a side chain containing an ion exchange group; The monomer with a side chain containing an ion exchange group comprises one or more of a perfluorosulfonyl fluoride monomer with a side chain containing a sulfonyl fluoride group and a perfluorocarboxylate monomer with a side chain containing a carboxylate group; The polar organic solution is an aqueous solution of a polar organic solvent; The mass percentage of the polar organic solvent in the polar organic solution is 30-100%; The molar ratio of the basic hydrolysis catalyst to the ion exchange group in the perfluorinated ion exchange resin is (2-10):1; The perfluorinated ion exchange resin accounts for 0.5-50% of the total mass of the polar organic solution and the perfluorinated ion exchange resin.

2. The ionization process for the perfluorinated ion exchange resin according to claim 1, wherein the polar organic solvent is one or more of methanol, ethanol, ethylene glycol, n-propanol, isopropanol, n-butanol, acetone, glycerol, butanediol, propylene glycol, N-methyl pyrrolidone, N, N-dimethylformamide, dimethyl sulfoxide, and N, N-dimethylacetamide.

3. The ionization process for the perfluorinated ion exchange resin according to claim 1, wherein the basic hydrolysis catalyst is one or more of sodium hydroxide, potassium hydroxide, lithium hydroxide, cesium hydroxide, rubidium hydroxide, ammonia, triethylamine, sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, lithium carbonate, lithium bicarbonate, and ammonium carbonate.

4. The ionization process for the perfluorinated ion exchange resin according to claim 1, wherein the hydrolysis temperature is 60-280°C, and the hydrolysis time is 1-96h.

5. The ionization process for the perfluorinated ion exchange resin according to claim 1, wherein the perfluorophosphate monomer with a side chain containing a phosphate group has a structure selected from one or more of formula (I) and formula (II): In formula (I), m is an integer of 0-12, and n is an integer of 0-12, In formula (II), m is an integer of 0-6, 6. The ionization process for the perfluorinated ion exchange resin according to claim 5, wherein m in formula (I) is an integer of 0-6.

7. The ionization process for the perfluorinated ion exchange resin according to claim 5, wherein m in formula (I) is an integer of 1-3. Formula (I), 8. The ionization process for the perfluorinated ion exchange resin according to claim 5, wherein n in formula (I) is an integer of 0-6. R groups are C x H 2x+1 wherein x is an integer from 1 to 12; formula (II), 9. The ionization process for the perfluorinated ion exchange resin according to claim 5, wherein n in formula (I) is an integer of 1-3. R groups are C x H 2x+1 wherein x is an integer from 1 to 12.

10. The ionization process for the perfluorinated ion exchange resin according to claim 5, wherein 11. The ionization process for the perfluorinated ion exchange resin according to claim 5, wherein ​ ​ ​ ​ ​ ​ ​ In formula (I), the R group is C x H 2x+1 wherein x is an integer from 1 to 6. ​ In formula (I), the R group is C x H 2x+1 wherein x is an integer from 1 to 3.

12. The ionization process for perfluorinated ion exchange resin according to claim 5, wherein, in formula (II), m is an integer of 0 to 3.

13. The ionization process for perfluorinated ion exchange resin according to claim 5, wherein, in formula (II), m is an integer of 0 to 1.

14. The ionization process for perfluorinated ion exchange resin according to claim 5, wherein, In formula (II), the R group is C x H 2x+1 wherein x is an integer from 1 to 6.

15. The ionization process for perfluorinated ion exchange resin according to claim 5, wherein, In formula (II), the R group is C x H 2x+1 wherein x is an integer from 1 to 3.

16. The ionization process for perfluorinated ion exchange resin according to claim 1, wherein, the perfluorosulfonyl fluoride monomer having a side chain containing a sulfonyl fluoride group has a structural formula selected from formula (III): Formula (III) in formula (III), m is an integer of 0 to 6; n is an integer of 0 to 12.

17. The ionization process for perfluorinated ion exchange resin according to claim 16, wherein, in formula (III), m is an integer of 0 to 3.

18. The ionization process for perfluorinated ion exchange resin according to claim 16, wherein, in formula (III), m is an integer of 0 to 1.

19. The ionization process for perfluorinated ion exchange resin according to claim 16, wherein, in formula (III), n is an integer of 0 to 8.

20. The ionization process for perfluorinated ion exchange resin according to claim 16, wherein, in formula (III), n is an integer of 0 to 4.

21. The ionization process for perfluorinated ion exchange resin according to claim 1, wherein, the perfluorocarboxylate monomer having a side chain containing a carboxylate group has a structural formula selected from formula (IV): Formula (IV), in formula (IV), m is an integer of 0 to 12 n is an integer of 0 to 12. R groups are C x H 2x+1 wherein x is an integer from 1 to 12.

22. The ionization process for perfluorinated ion exchange resin according to claim 21, wherein, in formula (IV), m is an integer of 0 to 6.

23. The ionization process for perfluorinated ion exchange resin according to claim 21, wherein, in formula (IV), m is an integer of 1 to 3.

24. The ionization process for perfluorinated ion exchange resin according to claim 21, wherein, in formula (IV), n is an integer of 0 to 8.

25. The ionization process for perfluorinated ion exchange resin according to claim 21, wherein, in formula (IV), n is an integer of 0 to 4.

26. The ionization process for perfluorinated ion exchange resin according to claim 21, wherein, In formula (IV), the R group is C x H 2x+1 wherein x is an integer from 1 to 6.

27. The ionization process for perfluorinated ion exchange resin according to claim 21, wherein, In formula (IV), the R group is C x H 2x+1 wherein x is an integer from 1 to 3.

28. The ionization process for perfluorinated ion exchange resin according to claim 1, wherein, the perfluorinated ion exchange resin is 0.5 to 30% of the total mass of the polar organic solution and the perfluorinated ion exchange resin.

29. The ionization process for perfluorinated ion exchange resin according to claim 1, wherein, (1) adding perfluorinated ion exchange resin into hydrolysis solution to obtain resin-hydrolysis solution mixture; (2) heating and stirring the resin-hydrolysis solution mixture to carry out hydrolysis reaction; (3) cooling the product obtained in step (2) to normal temperature, removing impurities, and acidifying to obtain perfluorinated ion exchange resin containing phosphoric acid, sulfonic acid and / or carboxylic acid.

30. Use of an ionization process as claimed in claim 1, characterized in that, The application fields include: proton exchange membrane fuel cell electrode, electrolyte film, polytetrafluoroethylene surface hydrophilic treatment, catalyst coating, electrochemical sensor production, electrochemical device.

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