Preparation method of proton exchange membrane

Abstract

The invention provides a proton exchange membrane preparation method, which comprises: dissolving SPEEK-Na < + > and ABPBI according to a certain mass ratio in a mixed dissolving agent, stirring, and simultaneously dissolving SPEEK-Na < + > and ABPBI by using the mixed dissolving agent to form a polymer mixed homogeneous solution with a certain mass fraction; carrying out material forming treatment on the polymer mixed homogeneous solution to obtain an intermediate product; sequentially carrying out post-treatment on the intermediate product in a hydrogen peroxide solution, deionized water and a dilute sulfuric acid solution, and washing the intermediate product with deionized water until the intermediate product is neutral, so as to obtain the SPEEK / ABPBI proton exchange membrane. According to the method, the SPEEK and the ABPBI are simultaneously dissolved through the solvent, then the membrane is prepared through material forming, the composite proton exchange membrane formed by blending the SPEEK and the ABPBI can be obtained through aftertreatment, the process is simple and convenient, operation is easy, and the prepared composite membrane has good mechanical strength, proton conductivity, water absorption / water retention and acid absorption / acid storage capacity and has good proton conduction performance.

Description

Technical Field

[0001] The invention relates to polymer materials, and in particular to a method for preparing a proton exchange membrane. Background Art

[0002] Hydrogen energy is known as the next generation of clean energy, and proton exchange membrane fuel cells (PEMFCs) have attracted much attention as one of the most direct application scenarios of hydrogen energy. Proton exchange membranes are known as the "chips" of PEMFCs, and their proton conductivity (σ) and mechanical properties are key indicators for evaluating membranes. Among them, the size of proton conductivity depends largely on the water content in the membrane when the battery system is running. Therefore, in order to ensure the efficient operation of the battery stack, an external water and heat management device is generally required, which invisibly increases the size and cost of the battery stack system. Therefore, reducing the membrane's dependence on water and improving its mechanical properties is a convenient and effective way to reduce the volume of the battery stack system while reducing costs. SPEEK is often considered as a proton exchange membrane material due to its low cost and high ion selectivity, but its high swelling rate and low proton conductivity at low humidity limit its further application.

[0003] At present, the more ideal approach is to blend it with other polymer electrolytes to reduce its dependence on water, so as to meet the proton conductivity requirements under low humidity. For example, Chinese patent No. 201110034247.1 discloses an acid-base cross-linked proton exchange membrane and its preparation, in which sulfonated polyetheretherketone and polyetheretherketone-benzimidazole are blended to obtain a mixed acid-base blended composite membrane.

[0004] Regarding the above-mentioned prior art, the acid-base blended composite membrane is obtained by blending sulfonated polyetheretherketone and polyetheretherketone-benzimidazole. Although it can improve the swelling rate and proton conductivity of SPEEK, polyetheretherketone-benzimidazole is complex to synthesize and expensive, and its proton conductivity performance is still relatively low, and it is impossible to obtain an excellent proton conductivity performance at a low cost. Summary of the invention

[0005] The purpose of the present invention is to overcome the above technical deficiencies, propose a method for preparing a proton exchange membrane, and solve the technical problems in the prior art that polyetheretherketone-benzimidazole is complex to synthesize, expensive, and has relatively low proton conductivity.

[0006] In order to achieve the above technical objectives, the present invention adopts the following technical solutions: The present invention provides a method for preparing a proton exchange membrane, comprising the following steps: A certain mass ratio of SPEEK-Na + and ABPBI are dissolved in a mixed solvent and stirred to make SPEEK-Na +Dissolve simultaneously with ABPBI to form a polymer mixed homogeneous solution with a certain mass fraction. Perform material forming treatment on the polymer mixed homogeneous solution to obtain an intermediate product. Post-treat the intermediate product successively in hydrogen peroxide solution, deionized water, and dilute sulfuric acid solution, and then wash it with deionized water until neutral to obtain the SPEEK / ABPBI proton exchange membrane.

[0007] In some embodiments, the mixed solvent in step one is a mixed solution of dimethyl sulfoxide / methanol / KOH.

[0008] In some embodiments, the mass ratio of dimethyl sulfoxide / methanol / KOH in the mixed solvent in step one is 40:24:1.

[0009] In some embodiments, in the step of performing material forming treatment on the polymer mixed homogeneous solution to obtain an intermediate product, it includes: Electrospin the polymer mixed homogeneous solution at room temperature under set parameters to obtain a SPEEK-Na+ / ABPBI nanofiber mat in the form of sodium sulfonate; Thermally press it to obtain a SPEEK-Na+ / ABPBI nanofiber membrane.

[0010] In some embodiments, in the step of post-treating the intermediate product successively in hydrogen peroxide solution, deionized water, and dilute sulfuric acid solution, and then washing it with deionized water until neutral to obtain the SPEEK / ABPBI proton exchange membrane, it includes: Post-treat the SPEEK-Na+ / ABPBI nanofiber membrane successively in hydrogen peroxide solution, deionized water, and dilute sulfuric acid solution; Then wash it with deionized water until neutral to obtain a SPEEK / ABPBI composite nanofiber proton exchange membrane.

[0011] In some embodiments, in the step of performing material forming treatment on the polymer mixed homogeneous solution to obtain an intermediate product, it includes: Introduce the polymer mixed homogeneous solution into a flat dish, gradually raise the temperature to completely evaporate the solvent, and obtain an intermediate product with the solvent evaporated.

[0012] In some embodiments, in the step of post-treating the intermediate product successively in hydrogen peroxide solution, deionized water, and dilute sulfuric acid solution, and then washing it with deionized water until neutral to obtain the SPEEK / ABPBI proton exchange membrane, it includes: Post-treat the intermediate product successively in hydrogen peroxide solution, deionized water, and dilute sulfuric acid solution; Then wash it with deionized water until neutral to obtain a SPEEK / ABPBI composite proton exchange membrane.

[0013] In some embodiments, in the step of dissolving SPEEK-Na with a certain mass ratio + and ABPBI in a mixed solvent and stirring, the mixed solvent enables the simultaneous dissolution of SPEEK-Na + and ABPBI to form a polymer mixed homogeneous solution with a certain mass fraction, there is also a preparation step for ABPBI, and the preparation step for ABPBI is as follows: Add the monomers 3,4-diaminobenzoic acid, phosphorus pentoxide, and methanesulfonic acid into a reaction vessel; Then heat and react under the protection of an inert gas to obtain a viscous polymer liquid; Pour the viscous polymer liquid into a container filled with a large amount of deionized water to make it fibrous; Then wash with a large amount of deionized water and NaOH aqueous solution until neutral; Finally, obtain ABPBI through drying, weigh it, bag it, and reserve it for use.

[0014] In some embodiments, in the step of dissolving SPEEK-Na with a certain mass ratio + and ABPBI in a mixed solvent and stirring, the mixed solvent enables the simultaneous dissolution of SPEEK-Na + and ABPBI to form a polymer mixed homogeneous solution with a certain mass fraction, there is also a preparation step for SPEEK-Na + The preparation step for SPEEK-Na + is as follows: Dissolve polyether ether ketone in concentrated sulfuric acid and react at a constant temperature for a period of time; Then pour it into ice water to draw filaments to obtain polymer filaments; Wash again with deionized water until the aqueous solution is neutral; Finally, dry the polymer to obtain sulfonated polyether ether ketone; Put the prepared sulfonated polyether ether ketone into a NaOH aqueous solution, heat and react to turn the sulfonated polyether ether ketone from light yellow to white; Finally, wash it thoroughly with deionized water until the solution is neutral, and dry to obtain SPEEK-Na + polymer salt.

[0015] In some embodiments, in the step of post-treating the intermediate product successively in hydrogen peroxide solution, deionized water, and dilute sulfuric acid solution, and then washing with deionized water until neutral to obtain the SPEEK / ABPBI proton exchange membrane, the concentration of the hydrogen peroxide solution is 3%, and the concentration of the dilute sulfuric acid solution is 5%.

[0016] Compared with the prior art, the method for preparing a proton exchange membrane provided by the present invention simultaneously dissolves SPEEK and ABPBI with a solvent, then forms a membrane through material shaping, and a composite proton exchange membrane blended with SPEEK and ABPBI can be obtained through post-treatment. The process is simple and convenient to operate, and the prepared composite membrane has good mechanical strength, proton conductivity, water absorption / retention, and acid absorption / acid storage capabilities, and has better proton conduction performance. Brief Description of the Drawings

[0017] Figure 1 SEM images of SPEEK fiber felt, SPEEK / ABPBI fiber felt, and their hot-pressed membranes; Figure 2 Stress-strain tensile diagram of SPEEK / ABPBI fiber membrane; Figure 3 Proton conductivity diagram. Detailed Description of the Embodiments

[0018] In order to make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. 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.

[0019] In order to solve the technical problems of complex synthesis, high price, and relatively low proton conduction performance of polyether ether ketone-benzimidazole, the present invention provides a method for preparing a proton exchange membrane, which can realize the preparation of a SPEEK / ABPBI composite membrane. The process is simple and convenient to operate, and the prepared composite membrane has good mechanical strength, proton conductivity, water absorption / retention, and acid absorption / acid storage capabilities, and has better proton conduction performance.

[0020] It should be noted that the method for preparing a proton exchange membrane described in the present invention is used for, but not limited to, the preparation of proton exchange membranes for fuel cells, etc. For the convenience of description, in the present invention, only the application of the method for preparing a proton exchange membrane to the preparation of proton exchange membranes for fuel cells is taken as an example for description, and the principle of applying the method for preparing a proton exchange membrane to other types of equipment is substantially the same as that for the preparation of proton exchange membranes for fuel cells, and will not be elaborated here one by one.

[0021] Example 1 In this example, before the step of blending and preparing a proton exchange membrane, the synthesis of ABPBI is first carried out, and the specific steps are as follows: Add 3 g of monomer 3,4-diaminobenzoic acid, 6 g of phosphorus pentoxide, and 20 ml of methanesulfonic acid into a three-necked flask, and then under N 2In a protected atmosphere, react at 150 °C for 4 h to obtain a viscous polymer liquid. While it is still hot, pour it into a container filled with a large amount of deionized water to make it fibrous, then wash it with a large amount of deionized water and NaOH aqueous solution until it is neutral, and finally dry it in a vacuum drying oven for 24 h to obtain ABPBI. Weigh it and bag it for standby.

[0022] It can be understood that ABPBI is basic poly(2,5-benzimidazole).

[0023] It should be noted that ABPBI has excellent mechanical properties and has an ideal proton conductivity under low humidity conditions after acid doping.

[0024] In this embodiment, before the step of blending to prepare the proton exchange membrane, it is also necessary to first carry out the synthesis of SPEEK-Na + The specific steps are as follows: Weigh 28 g of polyether ether ketone and dissolve it in 200 ml of 96%-98% concentrated sulfuric acid. React at 50 °C for 8 h, then while it is still hot, pour the concentrated solution into a large amount of ice water to draw a large number of polymer filaments, and then wash it with a large amount of deionized water until the aqueous solution is neutral. Finally, place the polymer in a vacuum drying oven and dry it at 60 °C for 48 h to prepare SPEEK with a sulfonation degree of about 64%.

[0025] It can be understood that the abbreviation of polyether ether ketone is PEEK, and SPEEK is acidic sulfonated polyether ether ketone.

[0026] Then, put the dried SPEEK into 500 ml of 1 M NaOH aqueous solution and heat it at 50 °C for 24 h. SPEEK changes from light yellow to white. Finally, wash it thoroughly with a large amount of deionized water until the solution is neutral, and dry it in a 60 °C vacuum drying oven for 24 h to obtain SPEEK-Na + Polymer salt for standby. The obtained SPEEK-Na from the reaction + can effectively improve the compatibility of SPEEK and ABPBI and prevent the precipitation of ABPBI due to acid-base reaction in the SPEEK solution.

[0027] It should be noted that SPEEK is often considered as a proton exchange membrane material due to its low cost, high ion selectivity, etc., but its high swelling rate and low proton conductivity under low humidity limit its further application. Therefore, an alkaline ABPBI polymer is introduced into acidic SPEEK for blending, and then electrospinning is used to obtain a blended fiber membrane. This nanofiber membrane optimizes the proton transport path and forms an acid-base ion crosslinking network, which can solve the dependence of the SPEEK membrane proton conductivity on water and improve the mechanical properties of the membrane at the same time.

[0028] In this embodiment, after preparing SPEEK-Na+ After adding the ABPBI material, a proton exchange membrane is prepared by blending through electrospinning technology. The specific steps are as follows: Prepare the SPEEK / ABPBI composite fiber membrane by electrospinning technology. Dissolve SPEEK-Na + and ABPBI in a mixed solution of dimethyl sulfoxide / methanol / KOH and stir magnetically at 400 rpm for more than 48 h to form a polymer mixed homogeneous solution with a certain mass fraction. Then electrospin the polymer solution at room temperature under set parameters to obtain the SPEEK-Na + / ABPBI nanofiber mat. Hot press it at 150 °C and 5 MPa for more than 1 h to obtain the SPEEK-Na + / ABPBI nanofiber membrane.

[0029] Finally, post-treat it in 3% hydrogen peroxide solution, deionized water, and 5% dilute sulfuric acid solution for 1 h each, and wash it with deionized water until neutral to obtain the SPEEK / ABPBI nanofiber membrane. Finally, dry it in a vacuum oven, bag it, and set aside for subsequent testing.

[0030] It can be understood that the prepared membrane can form an ionic cross-linking network inside, construct rich proton transport channels, effectively improve the mechanical properties, reduce the level of phosphoric acid doping, and at the same time also have excellent proton conduction performance. It is a promising proton exchange membrane for fuel cells.

[0031] Furthermore, the mass ratio of SPEEK-Na + and ABPBI is one of 1:1, 2:1, 3:1, 4:1, 5:1. The above are preferred mass ratios. However, the mass ratio is not limited to the above several, and other mass ratios with corresponding preparation effects are also acceptable.

[0032] It should be noted that the certain mass fraction in step one can be 9-15 wt.%, and the parameters for electrospinning the polymer solution can be 20 KV and 15 cm; blending the two materials of SPEEK and ABPBI and electrospinning can optimize the proton conduction channels through nanofibers and reduce the water dependence of SPEEK.

[0033] Example 2 In this example, before the step of blending to prepare the proton exchange membrane, the synthesis of ABPBI is carried out first. The specific steps are as follows: Add 3 g of monomer 3,4-diaminobenzoic acid, 6 g of phosphorus pentoxide, and 20 ml of methanesulfonic acid to a three-necked flask, and then in N 2In a protected atmosphere, react at 150 °C for 4 h to obtain a viscous polymer liquid. While it is still hot, pour it into a container filled with a large amount of deionized water to make it fibrous, then wash it with a large amount of deionized water and NaOH aqueous solution until neutral, and finally dry it in a vacuum drying oven for 24 h to obtain ABPBI. Weigh it and bag it for later use.

[0034] In this example, before the step of blending to prepare the proton exchange membrane, it is also necessary to first carry out the synthesis of SPEEK-Na + The specific steps are as follows: Weigh 28 g of polyether ether ketone and dissolve it in 200 ml of 96%-98% concentrated sulfuric acid. React at 50 °C for 8 h, then while it is still hot, pour the concentrated solution into a large amount of ice water to draw a large number of polymer filaments, and then wash it with a large amount of deionized water until the aqueous solution is neutral. Finally, place the polymer in a vacuum drying oven and dry it at 60 °C for 48 h to prepare SPEEK with a sulfonation degree of about 64%.

[0035] Then, put the dried SPEEK into 500 ml of 1 M NaOH aqueous solution and heat it at 50 °C for 24 h. SPEEK changes from light yellow to white. Finally, wash it thoroughly with a large amount of deionized water until the solution is neutral, and dry it in a 60 °C vacuum drying oven for 24 h to obtain SPEEK-Na + Reserve the polymer salt for later use.

[0036] In this example, after preparing SPEEK-Na + and the ABPBI material, then blend and prepare the proton exchange membrane by the casting film method. The specific steps are as follows: Dissolve SPEEK-Na + and ABPBI in a mixed solution of dimethyl sulfoxide / methanol / KOH and magnetically stir at 400 rpm for more than 48 h to form a polymer mixed homogeneous solution with a certain mass fraction. Then pour it into a flat dish and gradually heat it from 80 °C to 110 °C to completely evaporate the solvent to obtain an intermediate product.

[0037] Treat the intermediate product in 3% hydrogen peroxide solution, deionized water, and 5% dilute sulfuric acid solution for 1 h each, and then wash it with deionized water until neutral to carry out the protonation process, converting the sodium sulfonate on SPEEK-Na + to sulfonic acid root. Finally, dry it in a vacuum oven, bag it, and wait for subsequent testing.

[0038] Furthermore, SPEEK-Na +The mass ratio of [substance] to ABPBI is one of 1:1, 2:1, 3:1, 4:1, 5:1. The above are preferred mass ratios. However, the mass ratio is not limited to the above several, and other mass ratios with corresponding preparation effects are also acceptable.

[0039] It should be noted that the certain mass fraction in Step 1 can be 9 - 15 wt.%; in the operation of gradually heating from 80°C to 110°C, the temperature is increased by 20°C per hour.

[0040] Control Example 1 In this control example, before the step of preparing the SPEEK fiber membrane, the preparation of SPEEK is also required first. The specific steps are as follows: Weigh 28 g of polyether ether ketone and dissolve it in 200 ml of 96% - 98% concentrated sulfuric acid. React at 50°C for 8 h. Then, while it is hot, pour the concentrated solution into a large amount of ice water to draw a large number of polymer filaments. Then wash with a large amount of deionized water until the aqueous solution is neutral. Finally, place the polymer in a vacuum drying oven and dry at 60°C for 48 h to prepare SPEEK with a sulfonation degree of about 64%.

[0041] In this control example, the electrospinning technique is used to prepare the SPEEK fiber membrane. The specific steps are as follows: Dissolve a certain mass fraction of SPEEK in dimethyl sulfoxide solution and magnetically stir at 400 rpm for more than 24 h to form a polymer homogeneous solution with a certain mass fraction. Then electrospin the polymer solution at room temperature under the set parameters to obtain a SPEEK nanofiber mat. Hot press it at 140°C and 5 MPa for more than 1 h, and then post - treat it in 3% hydrogen peroxide solution, deionized water, and 5% dilute sulfuric acid solution for 1 h each, and wash with deionized water until neutral to obtain the SPEEK nanofiber membrane. Dry it in a vacuum oven, bag it for standby and wait for subsequent testing.

[0042] It should be noted that SPEEK is an ionic polymer containing -SO3H on the main chain and is an ideal polymer electrolyte material with good thermal stability.

[0043] Control Example 2 In this control example, before the step of preparing the SPEEK fiber membrane, the preparation of SPEEK is also required first. The specific steps are as follows: Weigh 28 g of polyether ether ketone and dissolve it in 200 ml of 96%-98% concentrated sulfuric acid. React at 50 °C for 8 h. Then, while it is still hot, pour the concentrated solution into a large amount of ice water to draw a large number of polymer filaments. Wash with a large amount of deionized water until the aqueous solution is neutral. Finally, place the polymer in a vacuum drying oven and dry at 60 °C for 48 h to prepare SPEEK with a sulfonation degree of approximately 64%.

[0044] In this comparative example, the SPEEK membrane was prepared by a casting film-forming technique. The specific steps are as follows: Dissolve a certain mass fraction of SPEEK in a dimethyl sulfoxide solution and magnetically stir at 400 rpm for more than 24 h to form a polymer homogeneous solution with a certain mass fraction; Then pour it into a flat dish, gradually heat from 80 °C to 110 °C to completely evaporate the solvent, and then post-treat it in a 3% hydrogen peroxide solution, deionized water, and 5% dilute sulfuric acid solution for 1 h each, and wash with deionized water until neutral to obtain the SPEEK membrane; Dry in a vacuum oven, bag it for later use and wait for subsequent tests.

[0045] The specific embodiments of the present invention described above do not constitute a limitation to the protection scope of the present invention. Any other corresponding changes and deformations made according to the technical concept of the present invention should be included within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a proton exchange membrane, characterized in that: The following steps are involved: A certain mass ratio of SPEEK-Na + and ABPBI are dissolved in a mixed solvent and stirred to make SPEEK-Na + Dissolved simultaneously with ABPBI to form a polymer mixed homogeneous solution with a certain mass fraction; Performing material forming treatment on the polymer mixed homogeneous solution to obtain an intermediate product; The intermediate product was post-treated in a hydrogen peroxide solution, deionized water, and a dilute sulfuric acid solution in sequence, and then washed with deionized water until neutral, thereby obtaining a SPEEK / ABPBI proton exchange membrane.

2. The method for preparing a proton exchange membrane according to claim 1, characterized in that: The mixed solvent in step 1 is a mixed solution of dimethyl sulfoxide / methanol / KOH.

3. The method for preparing a proton exchange membrane according to claim 2, characterized in that: The mass ratio of dimethyl sulfoxide / methanol / KOH in the mixed solvent in step 1 is 40:24:

1.

4. The method for preparing a proton exchange membrane according to claim 1, characterized in that: In the step of subjecting the polymer mixed homogeneous solution to material shaping to obtain an intermediate product, the step comprises: The polymer mixed homogeneous solution was electrospun at room temperature under set parameters to obtain SPEEK-Na+ / ABPBI nanofiber mat in the form of sodium sulfonate; It was hot-pressed to obtain SPEEK-Na+ / ABPBI nanofiber membrane.

5. The method for preparing a proton exchange membrane according to claim 4, characterized in that: In the step, the intermediate product is post-treated in a hydrogen peroxide solution, deionized water, and a dilute sulfuric acid solution in sequence, and then washed with deionized water until neutral, to obtain a SPEEK / ABPBI proton exchange membrane, comprising: The SPEEK-Na+ / ABPBI nanofiber membrane was post-treated in hydrogen peroxide solution, deionized water, and dilute sulfuric acid solution in sequence; The mixture was then washed with deionized water until neutral to obtain a SPEEK / ABPBI composite nanofiber proton exchange membrane.

6. The method for preparing a proton exchange membrane according to claim 1, characterized in that: In the step of subjecting the polymer mixed homogeneous solution to material shaping to obtain an intermediate product, the step comprises: The polymer mixed homogeneous solution is introduced into a flat dish and the temperature is gradually increased to completely evaporate the solvent to obtain an intermediate product from which the solvent has been evaporated.

7. The method for preparing a proton exchange membrane according to claim 6, characterized in that: In the step, the intermediate product is post-treated in a hydrogen peroxide solution, deionized water, and a dilute sulfuric acid solution in sequence, and then washed with deionized water until neutral, to obtain a SPEEK / ABPBI proton exchange membrane, comprising: post-treating the intermediate product in hydrogen peroxide solution, deionized water, and dilute sulfuric acid solution in sequence; The mixture was then washed with deionized water until neutral to obtain a SPEEK / ABPBI composite proton exchange membrane.

8. The method for preparing a proton exchange membrane according to claim 1, characterized in that: In the step, a certain mass ratio of SPEEK-Na + and ABPBI are dissolved in a mixed solvent and stirred to make SPEEK-Na + Before dissolving the polymer and ABPBI at the same time to form a polymer mixed homogeneous solution with a certain mass fraction, the preparation step of ABPBI is also included. The preparation step of ABPBI is as follows: The monomer 3,4-diaminobenzoic acid, phosphorus pentoxide and methane sulfonic acid are added to the reaction vessel; Then, the reaction is heated under the protection of an inert gas to obtain a viscous polymer liquid; Then pour the viscous polymer liquid into a container filled with a large amount of deionized water to make it fibrous; Then wash with plenty of deionized water and NaOH aqueous solution until neutral; Finally, ABPBI is obtained by drying, weighing and bagging for later use.

9. The method for preparing a proton exchange membrane according to claim 1, characterized in that: In the step, a certain mass ratio of SPEEK-Na + and ABPBI are dissolved in a mixed solvent and stirred to make SPEEK-Na + SPEEK-Na and ABPBI are dissolved simultaneously to form a polymer mixed homogeneous solution with a certain mass fraction. + Preparation steps of SPEEK-Na + The preparation steps are as follows: Dissolve polyetheretherketone in concentrated sulfuric acid and react at a constant temperature for a period of time; Then pour into ice water and draw to obtain polymer filaments; Then rinse with deionized water until the aqueous solution is neutral; Finally, the polymer is dried to obtain sulfonated polyetheretherketone; The prepared sulfonated polyetheretherketone is placed in a NaOH aqueous solution and heated to react, so that the sulfonated polyetheretherketone changes from light yellow to white; Finally, it was fully washed with deionized water until the solution was neutral, and then dried to obtain SPEEK-Na + Polymer salts.

10. The method for preparing a proton exchange membrane according to claim 1, characterized in that: In the step, the intermediate product is post-treated in a hydrogen peroxide solution, deionized water, and a dilute sulfuric acid solution in sequence, and then washed with deionized water to neutrality, thereby obtaining a SPEEK / ABPBI proton exchange membrane in which the solubility of the hydrogen peroxide solution is 3% and the concentration of the dilute sulfuric acid solution is 5%.

Images