Perfluorosulfonyl imide type proton exchange resin with coupled multi-element active center as well as preparation method and application of perfluorosulfonyl imide type proton exchange resin

Abstract

The invention discloses a perfluorosulfonyl imide type proton exchange resin with a coupled multi-active center, which is obtained by grafting phosphonated polyhedral oligomeric silsesquioxane (POSS) on perfluorosulfonamide, and the specific preparation process is as follows: perfluorosulfonyl fluoride and ammonia gas react to generate perfluorosulfonamide; carrying out substitution reaction on the phosphonated POSS and triethyl phosphite to obtain an intermediate product; and carrying out Michael addition reaction on the intermediate product and perfluorosulfonylamino, and acidifying to obtain the target product. According to the perfluorosulfonyl imide type proton exchange resin with the coupled multi-element active center, the glass-transition temperature of a proton exchange membrane can be increased; meanwhile, the sulfonyl imide and the phosphonic acid group cooperatively construct a multiple proton transmission path and have rapid proton conduction capability, so that the proton exchange membrane can ensure rapid proton transmission even at a high temperature, the conductivity of the proton exchange membrane is improved, and the problem that a perfluorosulfonic acid proton exchange membrane in the prior art is relatively poor in performance under a high-temperature working condition is solved.

Description

Technical Field

[0001] 1. This invention belongs to the field of proton exchange membrane fuel cells, specifically relating to a perfluorosulfonamide type proton exchange resin with coupled multi-functional active centers, its preparation method, and its application. Background Technology

[0002] A proton exchange membrane fuel cell (PEMFC) is a device that converts hydrogen into electrical energy, boasting advantages such as high energy conversion efficiency and fast system response, making it an ideal power supply device. However, one of the challenges facing high-temperature proton exchange membrane fuel cells (HT-PEMFC) is that the electrolyte membrane must possess ideal proton conductivity and high-temperature stability to meet the requirements of fuel cells under high temperature and low hydration levels.

[0003] Currently, the commercially available ionomer is Nafion-type perfluorosulfonic acid resin, with a glass transition temperature of approximately 110°C. When operating under high-temperature conditions for extended periods, the polymer backbone undergoes chain segment relaxation and structural reorganization under sustained high temperatures, ultimately leading to a decline in the mechanical properties of the membrane material and damage to proton transport channels. Therefore, the stability of Nafion membranes decreases at higher temperatures. Furthermore, as the water content within the membrane decreases above 100°C, the hydration channels in its microstructure are prone to structural collapse in high-temperature environments. Coupled with the rapid evaporation of free water, this results in an exponential decrease in proton conductivity.

[0004] In traditional research on the doping of inorganic or organic fillers into proton exchange membranes, simple physical blending is often used to incorporate inorganic nanoparticles into polymers. However, nanoparticles cannot form stable chemical bonds with polymer chains and are easily lost during use. Furthermore, significant particle aggregation occurs within the membrane, affecting the stability and lifespan of the proton exchange membrane. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers to address the shortcomings of the prior art, thereby solving the problem of poor performance of perfluorosulfonic acid proton exchange membranes under high-temperature conditions in the traditional technology.

[0006] The technical solution adopted by the present invention to solve the above-mentioned problems is as follows: A perfluorosulfonamide-type proton exchange resin with coupled multi-functional active centers is prepared by grafting phosphorylated cage-type polysilsesquioxane (POSS) onto a perfluorosulfonamide.

[0007] According to the above scheme, the preferred structural formula of the perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers is Formula 1: Formula 1 Where n is an integer from 2 to 4, and the ion exchange equivalent EW is 700 to 1100 g / mol.

[0008] Based on the above, the present invention also provides a method for preparing the perfluorosulfonylimide type proton exchange resin having coupled multi-functional active centers, comprising the following steps: S1, Perfluorosulfonyl fluoride reacts with ammonia to form perfluorosulfonamide, as shown in Equation 2: Formula 2 Among them, the ion exchange equivalent (EW) of perfluorosulfonyl fluoride is 700–1100 g / mol, and n is an integer from 2 to 4; S2, Compound I containing the POSS structure undergoes a substitution reaction with triethyl phosphite to give Compound II. The reaction equation is shown in Equation 3, taking octachloropropylsilsesquioxane as an example of Compound I with the POSS structure: Formula 3; S3, after compound II reacts with perfluorosulfonamide via Michael addition reaction and is then acidified, compound III is obtained, which is a perfluorosulfonamide-type proton exchange resin with coupled multi-functional active centers. The reaction equation is shown in Equation 4: Formula 4.

[0009] Based on the above technical solution, preferably, in step S1, ammonia gas needs to be converted into liquid ammonia for the reaction. The reaction temperature is -80~-30℃. During the reaction, ammonia gas needs to be added in small amounts in batches to control the rate of ammonia liquefaction. The reaction time is 24~96h.

[0010] Based on the above technical solution, in step S1, the molar ratio between perfluorosulfonyl fluoride and ammonia is 1:1.5~6. When ammonia is added in small amounts multiple times, it is generally added in 2~4 portions.

[0011] Based on the above technical solution, step S1, after the reaction is completed, also includes acid washing and / or water washing to remove excess ammonia, thereby obtaining clean perfluorosulfonamide.

[0012] Based on the above technical solution, in step S2, the molar ratio of triethyl phosphite to compound I containing the POSS structure is 15:1 to 10:1.

[0013] Based on the above technical solution, in step S2, compound I containing the POSS structure is preferably octachloropropyl silsesquioxane, but other chlorinated alkyl silsesquioxanes can also be selected. That is, R in compound I can also be other chlorinated alkyl groups, and R can be represented as -(CH2). m Cl (Formula 3 is based on R being -(CH2)3Cl as an example), m is preferably 1~5.

[0014] Based on the above technical solution, preferably, the specific process of step S2 is as follows: Compound I containing the POSS structure is fully dissolved and mixed with triethyl phosphite in dimethyl sulfoxide, then nitrogen gas is introduced, and the mixture is refluxed at 140~180℃ for 8~24h. After rotary evaporation, the resulting solid is compound II.

[0015] Based on the above technical solution, in step S3, the molar ratio of perfluorosulfonamide to compound II is 1:2 to 1:4; the molar ratio of perfluorosulfonamide to triethylamine, the acid-binding agent, is 1:2 to 1:10; the Michael addition reaction is carried out in an organic solvent and a protective atmosphere is provided.

[0016] Based on the above technical solution, preferably, the specific process of step S3 is as follows: dissolve perfluorosulfonamide in N,N-dimethylformamide, add the catalyst triethylamine and compound II, and then stir the reaction continuously at 80~100℃ for 24h~72h under nitrogen protection. Then, precipitate the solid with ethyl acetate, wash until neutral, and then protonate with hydrochloric acid for 12h~24h. After washing and drying, compound III is finally obtained, which is a perfluorosulfonamide type proton exchange resin with coupled multi-functional active centers.

[0017] Based on the above, the present invention also provides a perfluorosulfonamide-type proton exchange membrane with coupled multi-functional active centers, that is, the perfluorosulfonamide-type proton exchange resin with coupled multi-functional active centers is prepared into a membrane, and the specific preparation method is as follows: A perfluorosulfonylimide proton exchange resin with coupled multi-functional active centers is dissolved in N,N-dimethylformamide solvent with a solid content of 10%~20%. The solution is then heated and stirred at 120~150℃ for 12h~24h to obtain a resin solution. The resulting resin solution is coated onto a clean glass plate and dried at 60~80℃ for 12h~24h to form a film. The film is then annealed at 120~150℃ for 2~4h. This step increases the crystallinity of the polymer and removes residual solvent, resulting in a proton exchange membrane. The annealed proton exchange membrane undergoes further post-treatment: it is first immersed in dilute sulfuric acid at 80~100℃ for 12~24h to achieve full protonation, then washed with water and dried to obtain a perfluorosulfonylimide proton exchange membrane with coupled multi-functional active centers.

[0018] Compared with the prior art, the beneficial effects of the present invention are: First, the perfluorosulfonylimide proton exchange resin with coupled multi-functional active centers described in this invention is prepared by grafting a phosphonic acid functionalized POSS structure onto the side chains of a perfluorosulfonic acid resin. The POSS structure has a large volume and can generate a strong chain segment movement confinement effect, thereby increasing the glass transition temperature of the proton exchange membrane. At the same time, the POSS has phosphonic acid functionalization, which can construct a high-density proton transport network. The abundant active groups provide rapid proton conduction capability, enabling the proton exchange membrane to ensure rapid proton transport even under low humidity and high temperature conditions.

[0019] Second, in the perfluorosulfonylimide-type proton exchange resin with coupled multi-functional active centers described in this invention, sulfonylimide and phosphonic acid groups synergistically construct multiple proton transport pathways: on the one hand, transport occurs through a hydrated hydrogen ion-dependent carrier mechanism, and on the other hand, migration is accomplished through a proton hopping mechanism between acidic functional groups; moreover, the multi-acid side chain structure in the resin can form a unique hydrogen bond network with water molecules, providing a favorable microenvironment for proton conduction, thereby improving the conductivity of the proton exchange membrane. Attached Figure Description

[0020] Figure 1 Comparison of glass transition temperatures of the resin-prepared membrane and the Nafion membrane in Example 1; Figure 2 Comparison of tensile strength between the resin-prepared membrane and the Nafion membrane in Example 1; Figure 3 A comparison of the conductivity of the membrane prepared by the resin in Example 1 and the Nafion membrane at different temperatures and 100% RH. Detailed Implementation

[0021] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the present invention is not limited to the following embodiments.

[0022] This invention provides a perfluorosulfonamide-type proton exchange resin with coupled multi-functional active centers, the preparation method of which specifically includes the following steps: (1) Perfluorosulfonyl fluoride and ammonia react at -80~-30℃ for 24~96h to generate perfluorosulfonamide; wherein, ammonia is converted into liquid ammonia for the reaction, and ammonia is added in 2~4 times during the reaction. (2) Triethyl phosphite and compound I containing the POSS structure are fully dissolved and mixed in dimethyl sulfoxide, then nitrogen gas is introduced, and the mixture is refluxed at 140~180℃ for 8~24h. After rotary evaporation, the solid obtained is compound II. (3) Dissolve perfluorosulfonamide in N,N-dimethylformamide, add triethylamine as an acid binder and compound II, and then stir continuously at 80~100℃ for 24h~72h under nitrogen protection. Then precipitate the solid with ethyl acetate, wash until neutral, and then protonate with hydrochloric acid for 12h~24h. After washing and drying, compound III is finally obtained, which is a perfluorosulfonamide type proton exchange resin with coupled multi-functional active centers.

[0023] Further, in step (1), the molar ratio between perfluorosulfonyl fluoride and ammonia is 1:1.5~6; in step (2), the molar ratio between triethyl phosphite and compound I containing the POSS structure is 15:1~10:1; in step (3), the molar ratio between perfluorosulfonamide and compound II is 1:2~1:4, and the molar ratio between perfluorosulfonamide and the acid-binding agent triethylamine is 1:2~1:10.

[0024] The perfluorosulfonyl fluoride used in this invention has an EW value of 700–1100 g / mol, is suitable for this invention, and is a commercially available raw material. This invention preferably uses the following three structural formulas 5, 6, and 7, named perfluorosulfonyl fluoride-850, perfluorosulfonyl fluoride-1050, and perfluorosulfonyl fluoride-790, respectively, with the following structures: Formula 5 Formula 6 Formula 7 Among them, the EW value of perfluorosulfonyl fluoride-850 is 850 g / mol, the EW value of perfluorosulfonyl fluoride-1050 is 1050 g / mol, and the EW value of perfluorosulfonyl fluoride-790 is 790 g / mol.

[0025] In the following examples, compound I containing the POSS structure is octachloropropylsilsesquioxane (OCP-POSS), a commercially available raw material that can be purchased from the Innocare website.

[0026] Example 1 A perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers has the structural formula shown in Formula 1, where n is 4 and EW value is 850 g / mol. The specific preparation method includes the following steps: S1. Add 10 mmol / L of perfluorosulfonyl fluoride-850 to a single-necked flask, place it in a low-temperature bath, and maintain... The mixture was heated to 78°C, and then 800 mL of NH3 (approximately 36 mmol) was continuously introduced four times using a balloon, 200 mL each time. The mixture was stirred for 72 h. After the reaction was completed, the mixture was heated to 80°C, and 200 mL of 1 mol / L dilute sulfuric acid was added to neutralize the excess NH3. The mixture was then washed with deionized water until neutral to obtain the product perfluorosulfonamide-850.

[0027] S2. Take 3 mmol of compound I containing the POSS structure and add it to a flask containing 20 ml of dimethyl sulfoxide. Heat to 160 °C and stir to dissolve. Then add 36 mmol of triethyl phosphite (the molar ratio of triethyl phosphite to compound I containing the POSS structure is 12:1). Purge with nitrogen and reflux at 160 °C for 16 h. Then, rotary evaporate the solid in the reaction solution. Wash with water three times and dry to obtain the product, which is compound II.

[0028] S3. Dissolve 1 mmol of perfluorosulfonamide-850 in 100 ml of N,N-dimethylformamide, then add 6 mmol of triethylamine and 3 ml of compound II. React under nitrogen protection at 80°C with continuous stirring for 48 h. After the reaction, precipitate the solid with ethyl acetate. Wash the solid sequentially with deionized water and ethanol until neutral, then protonate it with hydrochloric acid for 12 h. Finally, wash with deionized water and dry to obtain compound III, which is a perfluorosulfonamide-type proton exchange resin with coupled multi-functional active centers. The chemical reaction formulas involved in the above two steps S2 and S3 are as follows:

[0029]

[0030] Example 2 A perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers has the structural formula shown in Formula 1, where n is 4 and EW value is 1050 g / mol. The specific preparation method includes the following steps: S1. Add 15 mmol / L of perfluorosulfonyl fluoride-1050 to a single-necked flask, place it in a low-temperature bath, and maintain... At 68°C, 600 mL of NH3 (approximately 27 mmol) was continuously introduced three times using a balloon, 200 mL each time, and the reaction was stirred for 72 h. After the reaction was completed, the temperature was raised to 80°C, and 200 mL of 1 mol / L dilute sulfuric acid was added to neutralize the excess NH3. The mixture was then washed with deionized water until neutral to obtain the product perfluorosulfonamide-1050.

[0031] S2. Take 3 mmol of compound I containing the POSS structure and add it to a flask containing 20 ml of dimethyl sulfoxide. Heat to 160 °C and stir to dissolve. Then add 36 mmol of triethyl phosphite (the molar ratio of triethyl phosphite to compound I containing the POSS structure is 12:1). Purge with nitrogen and reflux at 160 °C for 16 h. Then, rotary evaporate the solid in the reaction solution. Wash with water three times and dry to obtain the product, which is compound II.

[0032] S3. Dissolve 1 mmol of perfluorosulfonamide-1050 in 100 ml of N,N-dimethylformamide, then add 5 mmol of triethylamine (an acid-binding agent) and 2 mmol of compound II. The reaction is carried out under nitrogen protection at 100°C with continuous stirring for 72 h. After the reaction, the solid is precipitated with ethyl acetate. The solid is washed successively with deionized water and ethanol until neutral, then protonated with hydrochloric acid for 12 h. Finally, it is washed with deionized water and dried to obtain compound III, which is a perfluorosulfonamide-type proton exchange resin with coupled multi-functional active centers. The chemical reaction formulas involved in the above two steps S2 and S3 are as follows:

[0033]

[0034] Example 3 A perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers, with the structural formula shown in Formula 1, where n is 2 and EW value is 790 g / mol, is prepared by the following steps: S1. Add 8 mmol of perfluorosulfonyl fluoride-790 to a single-necked flask, place it in a low-temperature bath, and maintain it at -75°C. Then, continuously introduce 1000 mL of NH3 (about 45 mmol) five times using a balloon, 200 mL each time, and stir the reaction for 72 h. After the reaction is completed, heat it to 80°C and add 400 mL of 1 mol / L dilute sulfuric acid to neutralize the excess NH3. Then wash with deionized water until neutral to obtain the product perfluorosulfonamide-790.

[0035] S2. Take 3 mmol of compound I containing the POSS structure and add it to a flask containing 20 ml of dimethyl sulfoxide. Heat to 160 °C and stir to dissolve. Then add 36 mmol of triethyl phosphite (the molar ratio of triethyl phosphite to compound I containing the POSS structure is 12:1). Purge with nitrogen and reflux at 160 °C for 16 h. Then, rotary evaporate the solid in the reaction solution. Wash with water three times and dry to obtain the product, which is compound II.

[0036] S3. Dissolve 1 mmol of perfluorosulfonamide-790 in 50 ml of N,N-dimethylformamide, then add 10 mmol of triethylamine (an acid-binding agent) and 4 mmol of compound II. The reaction is carried out under nitrogen protection at 90°C with continuous stirring for 48 h. After the reaction, the solid is precipitated with ethyl acetate. The solid is washed successively with deionized water and ethanol until neutral, then protonated with dilute sulfuric acid for 12 h. Finally, it is washed with deionized water and dried to obtain compound III, which is a perfluorosulfonamide-type proton exchange resin with coupled multi-functional active centers. The chemical reaction formulas involved in the above two steps S2 and S3 are as follows:

[0037]

[0038] Application examples The perfluorosulfonylimide proton exchange resin prepared in the above embodiments was used to prepare a perfluorosulfonylimide proton exchange membrane with coupled multi-functional active centers. The specific preparation process is as follows: Each perfluorosulfonamide proton exchange resin was dissolved in N,N-dimethylformamide with a solid content of 15%. The solution was then heated and stirred at 130°C for 12 hours to dissolve the resin. The solution was then coated onto a clean glass plate and dried at 70°C for 12 hours to form a film. The film was then annealed at 120°C for 3 hours. After annealing, the film was immersed in dilute sulfuric acid at 90°C for 12 hours to achieve full protonation. The film was then washed three times with deionized water and finally dried in a vacuum drying oven to obtain the perfluorosulfonamide proton exchange membrane with coupled multi-functional active centers.

[0039] To evaluate the specific technical effects of the perfluorosulfonylimide type proton exchange resin and its proton exchange membrane prepared in each embodiment with coupled multi-functional active centers, specific performance tests were conducted on aspects such as ion exchange capacity, distance between hydrophilic clusters, glass transition temperature, mechanical strength, and proton conductivity.

[0040] (1) Ion exchange capacity was tested by acid-base titration. First, each membrane sample was thoroughly dried and weighed quickly. Then, the shredded membrane sample was immersed in a saturated NaCl solution and stirred for 24 hours to ensure H2O. + Ions were fully displaced. During titration, 0.1 M NaOH solution and an automatic titrator (Metrohm, 916 Ti-Touch) were used, and the titrator was calibrated with a standard buffer solution before titration. Finally, the ion exchange capacity (IEC) was calculated according to the formula, and the results are shown in Table 1.

[0041]

[0042] In the formula, V NaOH and C NaOH m represents the volume and concentration of the NaOH solution being titrated, respectively. dry membrane This indicates the quality of the dried film sample.

[0043] (2) The distance between hydrophilic clusters was calculated using Bragg's formula after small-angle X-ray scattering (SAXS) testing. The X-ray wavelength λ used in the instrument was 1.542 Å. The specific results are shown in Table 1. Bragg's formula is:

[0044] In the formula, q represents the scattering vector, and d represents the average spacing between hydrophilic ion clusters.

[0045] (3) The thermomechanical properties of the samples were tested using a PerkinElmer DMA8000 dynamic thermomechanical analyzer in the range of 20~160°C to characterize the glass transition temperature. T g ), see Table 1 and for details. Figure 1 .

[0046] (4) The mechanical properties of the proton exchange membrane were tested at room temperature using a universal testing machine (Shenzhen Sansi, CMT6202). The sample size was 10 mm × 80 mm, the test strain rate was 10 mm min⁻¹, and the load cell was 500 N. The specific results are shown in Table 1 and Table 2. Figure 2 .

[0047] (5) Proton conductivity was measured using the two-electrode AC impedance method on an electrochemical workstation (Solartron). The conductivity was measured at 1287°C, with the humidity controlled at 100% RH. The conductivity was tested every 10°C starting at 20°C, up to 120°C. Specific results are shown in Table 1 and... Figure 3 .

[0048] The testing process used perfluorosulfonic acid as a comparative example (the perfluorosulfonic acid was model Nafion™ 211, manufactured by DuPont, USA), and the testing conditions were exactly the same as those in each example.

[0049] Table 1. Performance of membranes in each embodiment

[0050] As shown in Table 1, the proton exchange membrane prepared from the perfluorosulfonamide-type proton exchange resin with coupled multi-functional active centers described in this invention exhibits a significantly higher ion exchange capacity than the Nafion membrane, more than doubling its capacity. Furthermore, the hydrophilic cluster spacing is larger than that of Nafion, implying faster proton transport. The proton conductivity at 80°C and 100% RH exceeds 195 mS / cm, reaching a maximum of approximately 228 mS / cm, far exceeding that of the Nafion membrane. The glass transition temperature and tensile strength are also improved compared to the Nafion membrane. Specifically, due to the higher EW value of the resin in Example 2, the ion exchange capacity and conductivity of the membrane are slightly lower than those in Examples 1 and 3, but still significantly better than the Nafion membrane. The side chains of the resin in Example 3 are slightly shorter than those in Examples 1 and 2, resulting in a slight increase in tensile strength and glass transition temperature. Additionally, the resin in Example 3 has the lowest EW, leading to better solubility. The proton exchange membrane prepared from the resin in Example 1 achieves a good balance of conductivity, mechanical strength, and glass transition temperature, exhibiting optimal performance.

[0051] Table 1 and Figure 1 , Figure 2The proton exchange membranes prepared in the demonstration examples exhibit glass transition temperatures of 140–148 °C and tensile strengths of 26–32 MPa; while the Nafion membrane has a glass transition temperature of only 131 °C and a tensile strength of 23 MPa. This demonstrates that the phosphonic acid POSS structure introduced in this invention can significantly improve the glass transition temperature and mechanical strength of the proton exchange membrane. The POSS structure has large steric hindrance, reducing the migration ability of side chains and decreasing its flexibility, thus restricting the relative movement of amorphous regions; moreover, phosphonic acid groups have amphoteric properties, readily forming hydrogen bonds with adjacent phosphonic acid side chains, hindering chain migration. Furthermore, the POSS structure provides seven modifiable sites for grafting phosphonic acid groups, and the number of phosphonic acid groups can improve the performance of the proton exchange membrane. Because the resin contains abundant phosphonic acid proton sources, the proton membrane has strong water absorption capacity, resulting in higher proton conductivity. (See Table 1 and...) Figure 3 It is evident that the proton conductivity of this proton exchange membrane is higher than that of the Nafion membrane in the temperature range of 30–80℃. This is because the abundant phosphonic acid groups have stronger hydrophilicity than the single sulfonic acid groups, and the silicon-oxygen structure in POSS also has a certain degree of water absorption. Furthermore, the cage-like POSS promotes the further expansion of the free volume of the polymer, which can accommodate more water molecules. Since the efficiency of proton transport depends on the content of water molecules, the synergy between the large number of phosphonic acid groups and the POSS structure further improves the conductivity of the proton exchange membrane.

[0052] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and modifications without departing from the inventive concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. A perfluorosulfonylimide type proton exchange resin having coupled multi-functional active centers, characterized in that, The perfluorosulfonamide type proton exchange resin is obtained by grafting phosphonic cage-type polysilsesquioxane onto perfluorosulfonamide.

2. A perfluorosulfonylimide type proton exchange resin having coupled multi-functional active centers, characterized in that, The structural formula is shown in Equation 1: Formula 1 The ion exchange equivalent (EW) is 700–1100 g / mol, and n is an integer from 2 to 4.

3. A method for preparing a perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers as described in claim 1 or 2, characterized in that, Includes the following steps: (1) Perfluorosulfonyl fluoride reacts with ammonia to form perfluorosulfonamide, and the reaction equation is shown in Equation 2: Formula 2 Among them, the ion exchange equivalent (EW) of perfluorosulfonyl fluoride is 700–1100 g / mol, and n is an integer from 2 to 4; (2) Phosphonophosphate-containing cage-like polysilsesquioxane compound I undergoes a substitution reaction with triethyl phosphite to give compound II; the reaction equation is shown in Formula 3: Formula 3; (3) Compound II reacts with perfluorosulfonamide via Michael addition reaction, followed by acidification, to obtain compound III, which is the perfluorosulfonamide-type proton exchange resin with coupled multi-functional active centers; the reaction equation is shown in Formula 4: Formula 4.

4. The method for preparing a perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers according to claim 3, characterized in that, In step (1), ammonia is converted into liquid ammonia for reaction. The reaction temperature is -80~-30℃. Ammonia is added in portions during the reaction, and the reaction time is 48~96h.

5. The method for preparing a perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers according to claim 3, characterized in that, In step (1), the molar ratio between perfluorosulfonyl fluoride and ammonia is 1:1.5~6; In step (2), the molar ratio of triethyl phosphite to compound I is 15:1 to 10:

1.

6. The method for preparing a perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers according to claim 3, characterized in that, The specific process of step (2) is as follows: Compound I and triethyl phosphite are fully dissolved and mixed in dimethyl sulfoxide, then nitrogen gas is introduced, and the mixture is refluxed at 140~180℃ for 8~24h. After rotary evaporation, the resulting solid is compound II.

7. The method for preparing a perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers according to claim 3, characterized in that, In step (3), the molar ratio of perfluorosulfonamide to compound II is 1:2 to 1:4; the molar ratio of perfluorosulfonamide to triethylamine, the acid-binding agent, is 1:2 to 1:10; the Michael addition reaction is carried out in an organic solvent and a protective atmosphere is provided.

8. The method for preparing a perfluorosulfonylimide type proton exchange resin with coupled multi-functional active centers according to claim 3, characterized in that, The specific process of step (3) is as follows: Dissolve perfluorosulfonamide in N,N-dimethylformamide, add the catalyst triethylamine and compound II, and then stir the reaction continuously at 80~100℃ for 24h~72h under nitrogen protection. Then, precipitate the solid with ethyl acetate, wash until neutral, and then protonate with hydrochloric acid for 12h~24h. After washing and drying, compound III is finally obtained, which is a perfluorosulfonamide type proton exchange resin with coupled multi-functional active centers.

9. A perfluorosulfonylimide type proton exchange membrane with coupled multi-functional active centers, characterized in that, The film is prepared using the perfluorosulfonamide type proton exchange resin as described in claim 1 or 2.

10. The method for preparing the perfluorosulfonylimide type proton exchange membrane with coupled multi-functional active centers as described in claim 9, characterized in that, The perfluorosulfonylimide type proton exchange resin of claim 1 or 2 is dissolved in a solvent and heated and stirred to obtain a resin solution; the obtained resin solution is coated on a clean substrate and dried to form a film; then the film is annealed and then immersed in acid to achieve protonation, thereby obtaining the perfluorosulfonylimide type proton exchange membrane with coupled multi-functional active centers.

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