Preparation process of composite enhanced perfluorosulfonic acid proton exchange membrane

Abstract

The present invention belongs to the technical field of perfluorosulfonic acid proton exchange membrane preparation, and specifically relates to a preparation process for a composite enhanced perfluorosulfonic acid proton exchange membrane. The preparation process comprises the following steps: (1) preparing a first polytetrafluoroethylene-based base membrane; (2) preparing a membrane-forming liquid; (3) coating the membrane-forming liquid on a glass plate, then evenly covering the first polytetrafluoroethylene-based base membrane on the membrane-forming liquid, then coating the first polytetrafluoroethylene-based base membrane with the membrane-forming liquid again, and finally heat treating and post-treating to prepare a composite enhanced perfluorosulfonic acid proton exchange membrane. In the preparation process for the composite enhanced perfluorosulfonic acid proton exchange membrane of the present invention, the first polytetrafluoroethylene-based base membrane and the perfluorosulfonic acid resin membrane-forming liquid act synergistically, and by improving the interfacial compatibility between the two, the composite enhanced perfluorosulfonic acid proton exchange membrane finally prepared has excellent mechanical strength, proton conduction, and the ability to inhibit gas permeation.

Description

Technical Field

[0001] The invention belongs to the technical field of perfluorosulfonic acid proton exchange membrane preparation, and specifically relates to a preparation process of a composite enhanced perfluorosulfonic acid proton exchange membrane. Background Art

[0002] At present, homogeneous proton exchange membranes are difficult to adapt to the complex and multi-functional requirements of fuel cells (such as humidity, temperature, mechanical properties, and water transport within the membrane of electromigration water and back-diffusion water). Therefore, composite proton exchange membranes are an important research direction. Since the swelling of perfluorosulfonic acid proton exchange membranes in hot water leads to a decrease in their mechanical strength, this is extremely unfavorable for the application of thin proton exchange membranes in fuel cells. In order to improve the mechanical stability of proton exchange membranes, mechanically reinforced proton exchange membranes can be prepared by compounding ionic polymers (proton conductive components) with support components. Based on the PTFE support component, the PTFE used in the reinforced membrane is divided into three categories: (1) expanded and stretched porous PTFE membrane; (2) PTFE woven yarn (embedded in the membrane); and (3) PTFE fiber (uniformly dispersed in the membrane). However, due to the basically symmetrical distribution of the CF bonds in the porous polytetrafluoroethylene molecular chain and the relatively regular molecular structure, the polarity of microporous PTFE is very small and the hydrophilicity is poor. The sulfonic acid group in the commonly used proton conductive component sulfonated polymer has good hydrophilicity, and there is an interfacial compatibility problem when the two are compounded.

[0003] Therefore, how to optimize the proton exchange membrane in the fuel cell and improve the proton conductivity of the proton exchange membrane while ensuring the mechanical strength of the prepared proton exchange membrane is a technical problem that needs to be solved urgently. Summary of the Invention

[0004] The purpose of the present invention is to provide a process for preparing a composite enhanced perfluorosulfonic acid proton exchange membrane. The proton exchange membrane prepared by the process has excellent mechanical strength and proton conduction performance.

[0005] The preparation process of the composite enhanced perfluorosulfonic acid proton exchange membrane of the present invention comprises the following steps:

[0006] (1) 2-hydroxyethyl methacrylate phosphate is added to a mixture of anhydrous ethanol and a nonionic fluorocarbon surfactant, and then α,α-diethoxyacetophenone is added and stirred evenly to prepare a mixed solution, a polytetrafluoroethylene-based base film is immersed in the mixed solution for 30-40 minutes, and after taking it out, the mixed solution is evenly coated on the polytetrafluoroethylene-based base film using a coater, and finally ultraviolet light curing is performed to prepare a first polytetrafluoroethylene-based base film;

[0007] (2) adding the perfluorosulfonic acid resin solution to a mixture of 2-hydroxyethylammonium formate and N-methylpyrrolidone and reacting at a constant temperature of 83-85°C for 48-50 hours to prepare a membrane-forming solution;

[0008] (3) The membrane-forming liquid prepared in step (2) is coated on a glass plate, and then the first polytetrafluoroethylene-based base film is evenly covered on the membrane-forming liquid, and then the membrane-forming liquid is coated again on the first polytetrafluoroethylene-based base film. Finally, after heat treatment and post-treatment, a composite enhanced perfluorosulfonic acid proton exchange membrane is prepared.

[0009] in:

[0010] In step (1), the mass concentration of 2-hydroxyethyl methacrylate phosphate in the mixed solution of anhydrous ethanol and non-ionic fluorocarbon surfactant is 5-7%.

[0011] The mass of the nonionic fluorocarbon surfactant in step (1) accounts for 0.08% of the total mass of anhydrous ethanol and the nonionic fluorocarbon surfactant. The nonionic fluorocarbon surfactant is Capstone-FS-31, and the manufacturer is DuPont China Group Co., Ltd. Shanghai Branch.

[0012] The mass of α,α-diethoxyacetophenone in step (1) accounts for 0.2% of the mass of 2-hydroxyethyl methacrylate phosphate.

[0013] In step (1), the UV curing temperature is room temperature, and the UV curing time is 6-8 minutes.

[0014] The polytetrafluoroethylene-based base film described in step (1) is manufactured by Shandong Senrong New Materials Co., Ltd., and the model number is SRM001-03.

[0015] The manufacturer of the perfluorosulfonic acid resin solution in step (2) is Chemours Chemical (Shanghai) Co., Ltd., the model is Nafion D2020, and the mass fraction is 20%.

[0016] In step (2), the 2-hydroxyethyl ammonium formate is an aqueous solution of 2-hydroxyethyl ammonium formate, and the mass fraction of the 2-hydroxyethyl ammonium formate solution is 13-15%.

[0017] The volume percentage of 2-hydroxyethylammonium formate and N-methylpyrrolidone in the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone in step (2) is 0.45:0.55.

[0018] In step (2), the mass ratio of the perfluorosulfonic acid resin solution to the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone is 1:0.075-0.10.

[0019] In step (3), the heat treatment is first performed at 103-105°C for 1.2-1.3 hours and then at 135-138°C for 15-18 minutes.

[0020] The post-treatment in step (3) is to cool the glass plate to room temperature after the heat treatment is completed, and then peel the film off the glass plate.

[0021] The present invention discloses a process for preparing a composite reinforced perfluorosulfonic acid proton exchange membrane. The process involves first modifying a polytetrafluoroethylene-based substrate membrane to improve its hydrophilicity and proton conductivity. Using 2-hydroxyethyl methacrylate phosphate as a polymerization monomer and α,α-diethoxyacetophenone as a photoinitiator, phosphate groups are introduced into the polytetrafluoroethylene-based substrate membrane via a photocuring reaction to improve its hydrophilicity. The nonionic fluorocarbon surfactant Capstone-FS-31 is then introduced to provide pathways for proton transfer within the polytetrafluoroethylene-based substrate membrane. The perfluorosulfonic acid resin solution is then modified with a mixture of 2-hydroxyethylammonium formate and N-methylpyrrolidone. 2-Hydroxyethylammonium formate, an ionic liquid, enhances water retention and transfer sites, creates aqueous ion channels that promote proton transfer within the membrane, and improves the interfacial compatibility and gas permeation resistance of the resulting membrane. The N-methylpyrrolidone prolongs the rearrangement and crystallization time of the perfluorosulfonic acid resin during membrane preparation, improving the mechanical properties and reducing the brittleness of the resulting composite membrane.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) In the preparation process of the composite enhanced perfluorosulfonic acid proton exchange membrane described in the present invention, the first polytetrafluoroethylene-based base membrane and the perfluorosulfonic acid resin membrane-forming liquid work synergistically to improve the interfacial compatibility between the two, so that the finally prepared composite enhanced perfluorosulfonic acid proton exchange membrane has excellent mechanical strength, proton conduction effect and ability to inhibit gas permeation.

[0024] (2) The preparation process of the composite enhanced perfluorosulfonic acid proton exchange membrane described in the present invention is simple, the parameters are easy to control, and the various steps work synergistically with each other to prepare a composite enhanced perfluorosulfonic acid proton exchange membrane with stable performance. DETAILED DESCRIPTION

[0025] The present invention will be further described below with reference to the examples.

[0026] Example 1

[0027] The preparation process of the composite enhanced perfluorosulfonic acid proton exchange membrane described in Example 1 comprises the following steps:

[0028] (1) 2-hydroxyethyl methacrylate phosphate is added to a mixture of anhydrous ethanol and a nonionic fluorocarbon surfactant, and then α,α-diethoxyacetophenone is added and stirred evenly to prepare a mixed solution, a polytetrafluoroethylene-based base film is immersed in the mixed solution for 35 minutes, and after taking it out, the mixed solution is evenly coated on the polytetrafluoroethylene-based base film using a coater, and finally ultraviolet light curing is performed to prepare a first polytetrafluoroethylene-based base film;

[0029] (2) adding the perfluorosulfonic acid resin solution to a mixture of 2-hydroxyethylammonium formate and N-methylpyrrolidone and reacting the mixture at 84°C for 49 hours to prepare a membrane-forming solution;

[0030] (3) The membrane-forming liquid prepared in step (2) is coated on a glass plate, and then the first polytetrafluoroethylene-based base film is evenly covered on the membrane-forming liquid, and then the membrane-forming liquid is coated again on the first polytetrafluoroethylene-based base film. Finally, after heat treatment and post-treatment, a composite enhanced perfluorosulfonic acid proton exchange membrane is prepared.

[0031] in:

[0032] In step (1), the mass concentration of 2-hydroxyethyl methacrylate phosphate in the mixed solution of anhydrous ethanol and non-ionic fluorocarbon surfactant is 6%.

[0033] The mass of the nonionic fluorocarbon surfactant in step (1) accounts for 0.08% of the total mass of anhydrous ethanol and the nonionic fluorocarbon surfactant. The nonionic fluorocarbon surfactant is Capstone-FS-31, and the manufacturer is DuPont China Group Co., Ltd. Shanghai Branch.

[0034] The mass of α,α-diethoxyacetophenone in step (1) accounts for 0.2% of the mass of 2-hydroxyethyl methacrylate phosphate.

[0035] In step (1), the UV curing temperature is room temperature and the UV curing time is 7 minutes.

[0036] The polytetrafluoroethylene-based base film described in step (1) is manufactured by Shandong Senrong New Materials Co., Ltd., and the model number is SRM001-03.

[0037] The manufacturer of the perfluorosulfonic acid resin solution in step (2) is Chemours Chemical (Shanghai) Co., Ltd., the model is Nafion D2020, and the mass fraction is 20%.

[0038] In step (2), the 2-hydroxyethyl ammonium formate is an aqueous solution of 2-hydroxyethyl ammonium formate, and the mass fraction of the 2-hydroxyethyl ammonium formate solution is 14%.

[0039] The volume percentage of 2-hydroxyethylammonium formate and N-methylpyrrolidone in the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone in step (2) is 0.45:0.55.

[0040] The mass ratio of the perfluorosulfonic acid resin solution to the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone in step (2) is 1:0.088.

[0041] In step (3), the heat treatment is first performed at 104°C for 1.25 h and then at 137°C for 16 min.

[0042] The post-treatment in step (3) is to cool the glass plate to room temperature after the heat treatment is completed, and then peel the film off the glass plate.

[0043] Example 2

[0044] The preparation process of the composite enhanced perfluorosulfonic acid proton exchange membrane described in Example 2 comprises the following steps:

[0045] (1) 2-hydroxyethyl methacrylate phosphate is added to a mixture of anhydrous ethanol and a nonionic fluorocarbon surfactant, and then α,α-diethoxyacetophenone is added and stirred evenly to prepare a mixed solution, a polytetrafluoroethylene-based base film is immersed in the mixed solution for 30 minutes, and after taking it out, the mixed solution is evenly coated on the polytetrafluoroethylene-based base film using a coater, and finally ultraviolet light curing is performed to prepare a first polytetrafluoroethylene-based base film;

[0046] (2) adding the perfluorosulfonic acid resin solution to a mixture of 2-hydroxyethylammonium formate and N-methylpyrrolidone and reacting at 83°C for 48 hours to prepare a membrane-forming solution;

[0047] (3) The membrane-forming liquid prepared in step (2) is coated on a glass plate, and then the first polytetrafluoroethylene-based base film is evenly covered on the membrane-forming liquid, and then the membrane-forming liquid is coated again on the first polytetrafluoroethylene-based base film. Finally, after heat treatment and post-treatment, a composite enhanced perfluorosulfonic acid proton exchange membrane is prepared.

[0048] in:

[0049] In step (1), the mass concentration of 2-hydroxyethyl methacrylate phosphate in the mixed solution of anhydrous ethanol and non-ionic fluorocarbon surfactant is 5%.

[0050] The mass of the nonionic fluorocarbon surfactant in step (1) accounts for 0.08% of the total mass of anhydrous ethanol and the nonionic fluorocarbon surfactant. The nonionic fluorocarbon surfactant is Capstone-FS-31, and the manufacturer is DuPont China Group Co., Ltd. Shanghai Branch.

[0051] The mass of α,α-diethoxyacetophenone in step (1) accounts for 0.2% of the mass of 2-hydroxyethyl methacrylate phosphate.

[0052] In step (1), the UV curing temperature is room temperature and the UV curing time is 6 minutes.

[0053] The polytetrafluoroethylene-based base film described in step (1) is manufactured by Shandong Senrong New Materials Co., Ltd., and the model number is SRM001-03.

[0054] The manufacturer of the perfluorosulfonic acid resin solution in step (2) is Chemours Chemical (Shanghai) Co., Ltd., the model is Nafion D2020, and the mass fraction is 20%.

[0055] In step (2), the 2-hydroxyethyl ammonium formate is an aqueous solution of 2-hydroxyethyl ammonium formate, and the mass fraction of the 2-hydroxyethyl ammonium formate solution is 13%.

[0056] The volume percentage of 2-hydroxyethylammonium formate and N-methylpyrrolidone in the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone in step (2) is 0.45:0.55.

[0057] In step (2), the mass ratio of the perfluorosulfonic acid resin solution to the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone is 1:0.075.

[0058] In step (3), the heat treatment is first performed at 103°C for 1.2 h and then at 135°C for 15 min.

[0059] The post-treatment in step (3) is to cool the glass plate to room temperature after the heat treatment is completed, and then peel the film off the glass plate.

[0060] Example 3

[0061] The preparation process of the composite enhanced perfluorosulfonic acid proton exchange membrane described in Example 3 comprises the following steps:

[0062] (1) 2-hydroxyethyl methacrylate phosphate is added to a mixture of anhydrous ethanol and a nonionic fluorocarbon surfactant, and then α,α-diethoxyacetophenone is added and stirred evenly to prepare a mixed solution, a polytetrafluoroethylene-based base film is immersed in the mixed solution for 40 minutes, and after taking it out, the mixed solution is evenly coated on the polytetrafluoroethylene-based base film using a coater, and finally ultraviolet light curing is performed to prepare a first polytetrafluoroethylene-based base film;

[0063] (2) adding the perfluorosulfonic acid resin solution to a mixture of 2-hydroxyethylammonium formate and N-methylpyrrolidone and reacting the mixture at 85°C for 50 hours to prepare a membrane-forming solution;

[0064] (3) The membrane-forming liquid prepared in step (2) is coated on a glass plate, and then the first polytetrafluoroethylene-based base film is evenly covered on the membrane-forming liquid, and then the membrane-forming liquid is coated again on the first polytetrafluoroethylene-based base film. Finally, after heat treatment and post-treatment, a composite enhanced perfluorosulfonic acid proton exchange membrane is prepared.

[0065] in:

[0066] In step (1), the mass concentration of 2-hydroxyethyl methacrylate phosphate in the mixed solution of anhydrous ethanol and non-ionic fluorocarbon surfactant is 7%.

[0067] The mass of the nonionic fluorocarbon surfactant in step (1) accounts for 0.08% of the total mass of anhydrous ethanol and the nonionic fluorocarbon surfactant. The nonionic fluorocarbon surfactant is Capstone-FS-31, and the manufacturer is DuPont China Group Co., Ltd. Shanghai Branch.

[0068] The mass of α,α-diethoxyacetophenone in step (1) accounts for 0.2% of the mass of 2-hydroxyethyl methacrylate phosphate.

[0069] In step (1), the UV curing temperature is room temperature and the UV curing time is 8 minutes.

[0070] The polytetrafluoroethylene-based base film described in step (1) is manufactured by Shandong Senrong New Materials Co., Ltd., and the model number is SRM001-03.

[0071] The manufacturer of the perfluorosulfonic acid resin solution in step (2) is Chemours Chemical (Shanghai) Co., Ltd., the model is Nafion D2020, and the mass fraction is 20%.

[0072] In step (2), the 2-hydroxyethyl ammonium formate is an aqueous solution of 2-hydroxyethyl ammonium formate, and the mass fraction of the 2-hydroxyethyl ammonium formate solution is 15%.

[0073] The volume percentage of 2-hydroxyethylammonium formate and N-methylpyrrolidone in the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone in step (2) is 0.45:0.55.

[0074] In step (2), the mass ratio of the perfluorosulfonic acid resin solution to the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone is 1:0.10.

[0075] In step (3), the heat treatment is first performed at 105°C for 1.3 h and then at 138°C for 18 min.

[0076] The post-treatment in step (3) is to cool the glass plate to room temperature after the heat treatment is completed, and then peel the film off the glass plate.

[0077] Comparative Example 1

[0078] The preparation process of the composite enhanced perfluorosulfonic acid proton exchange membrane described in this comparative example 1 consists of the following steps:

[0079] (1) 2-Hydroxyethyl methacrylate phosphate is added to anhydrous ethanol, and then α,α-diethoxyacetophenone is added and stirred evenly to prepare a mixed solution, a polytetrafluoroethylene-based base film is immersed in the mixed solution for 35 minutes, and after taking it out, the mixed solution is evenly coated on the polytetrafluoroethylene-based base film using a coater, and finally ultraviolet light curing is performed to prepare a first polytetrafluoroethylene-based base film;

[0080] (2) adding the perfluorosulfonic acid resin solution to a mixture of 2-hydroxyethylammonium formate and N-methylpyrrolidone and reacting the mixture at 84°C for 49 hours to prepare a membrane-forming solution;

[0081] (3) The membrane-forming liquid prepared in step (2) is coated on a glass plate, and then the first polytetrafluoroethylene-based base film is evenly covered on the membrane-forming liquid, and then the membrane-forming liquid is coated again on the first polytetrafluoroethylene-based base film. Finally, after heat treatment and post-treatment, a composite enhanced perfluorosulfonic acid proton exchange membrane is prepared.

[0082] in:

[0083] In step (1), the mass concentration of 2-hydroxyethyl methacrylate phosphate in anhydrous ethanol is 6%.

[0084] The mass of α,α-diethoxyacetophenone in step (1) accounts for 0.2% of the mass of 2-hydroxyethyl methacrylate phosphate.

[0085] In step (1), the UV curing temperature is room temperature and the UV curing time is 7 minutes.

[0086] The polytetrafluoroethylene-based base film described in step (1) is manufactured by Shandong Senrong New Materials Co., Ltd., and the model number is SRM001-03.

[0087] The manufacturer of the perfluorosulfonic acid resin solution in step (2) is Chemours Chemical (Shanghai) Co., Ltd., the model is Nafion D2020, and the mass fraction is 20%.

[0088] In step (2), the 2-hydroxyethyl ammonium formate is an aqueous solution of 2-hydroxyethyl ammonium formate, and the mass fraction of the 2-hydroxyethyl ammonium formate solution is 14%.

[0089] The volume percentage of 2-hydroxyethylammonium formate and N-methylpyrrolidone in the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone in step (2) is 0.45:0.55.

[0090] The mass ratio of the perfluorosulfonic acid resin solution to the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone in step (2) is 1:0.088.

[0091] In step (3), the heat treatment is first performed at 104°C for 1.25 h and then at 137°C for 16 min.

[0092] The post-treatment in step (3) is to cool the glass plate to room temperature after the heat treatment is completed, and then peel the film off the glass plate.

[0093] Comparative Example 2

[0094] The preparation process of the composite enhanced perfluorosulfonic acid proton exchange membrane described in this comparative example 2 consists of the following steps:

[0095] (1) 2-hydroxyethyl methacrylate phosphate is added to a mixture of anhydrous ethanol and a nonionic fluorocarbon surfactant, and then α,α-diethoxyacetophenone is added and stirred evenly to prepare a mixed solution, a polytetrafluoroethylene-based base film is immersed in the mixed solution for 35 minutes, and after taking it out, the mixed solution is evenly coated on the polytetrafluoroethylene-based base film using a coater, and finally ultraviolet light curing is performed to prepare a first polytetrafluoroethylene-based base film;

[0096] (2) adding the perfluorosulfonic acid resin solution to 2-hydroxyethylammonium formate and reacting at 84°C for 49 hours to prepare a membrane-forming solution;

[0097] (3) The membrane-forming liquid prepared in step (2) is coated on a glass plate, and then the first polytetrafluoroethylene-based base film is evenly covered on the membrane-forming liquid, and then the membrane-forming liquid is coated again on the first polytetrafluoroethylene-based base film. Finally, after heat treatment and post-treatment, a composite enhanced perfluorosulfonic acid proton exchange membrane is prepared.

[0098] in:

[0099] In step (1), the mass concentration of 2-hydroxyethyl methacrylate phosphate in the mixed solution of anhydrous ethanol and non-ionic fluorocarbon surfactant is 6%.

[0100] The mass of the nonionic fluorocarbon surfactant in step (1) accounts for 0.08% of the total mass of anhydrous ethanol and the nonionic fluorocarbon surfactant. The nonionic fluorocarbon surfactant is Capstone-FS-31, and the manufacturer is DuPont China Group Co., Ltd. Shanghai Branch.

[0101] The mass of α,α-diethoxyacetophenone in step (1) accounts for 0.2% of the mass of 2-hydroxyethyl methacrylate phosphate.

[0102] In step (1), the UV curing temperature is room temperature and the UV curing time is 7 minutes.

[0103] The polytetrafluoroethylene-based base film described in step (1) is manufactured by Shandong Senrong New Materials Co., Ltd., and the model number is SRM001-03.

[0104] The manufacturer of the perfluorosulfonic acid resin solution in step (2) is Chemours Chemical (Shanghai) Co., Ltd., the model is Nafion D2020, and the mass fraction is 20%.

[0105] In step (2), the 2-hydroxyethyl ammonium formate is an aqueous solution of 2-hydroxyethyl ammonium formate, and the mass fraction of the 2-hydroxyethyl ammonium formate solution is 14%.

[0106] The mass ratio of the perfluorosulfonic acid resin solution to 2-hydroxyethylammonium formate in step (2) is 1:0.088.

[0107] In step (3), the heat treatment is first performed at 104°C for 1.25 h and then at 137°C for 16 min.

[0108] The post-treatment in step (3) is to cool the glass plate to room temperature after the heat treatment is completed, and then peel the film off the glass plate.

[0109] Comparative Example 3

[0110] The preparation process of the composite enhanced perfluorosulfonic acid proton exchange membrane described in this comparative example 3 consists of the following steps:

[0111] (1) 2-hydroxyethyl methacrylate phosphate is added to a mixture of anhydrous ethanol and a nonionic fluorocarbon surfactant, and then α,α-diethoxyacetophenone is added and stirred evenly to prepare a mixed solution, a polytetrafluoroethylene-based base film is immersed in the mixed solution for 35 minutes, and after taking it out, the mixed solution is evenly coated on the polytetrafluoroethylene-based base film using a coater, and finally ultraviolet light curing is performed to prepare a first polytetrafluoroethylene-based base film;

[0112] (2) adding the perfluorosulfonic acid resin solution to N-methylpyrrolidone and reacting at 84°C for 49 hours to prepare a membrane-forming solution;

[0113] (3) The membrane-forming liquid prepared in step (2) is coated on a glass plate, and then the first polytetrafluoroethylene-based base film is evenly covered on the membrane-forming liquid, and then the membrane-forming liquid is coated again on the first polytetrafluoroethylene-based base film. Finally, after heat treatment and post-treatment, a composite enhanced perfluorosulfonic acid proton exchange membrane is prepared.

[0114] in:

[0115] In step (1), the mass concentration of 2-hydroxyethyl methacrylate phosphate in the mixed solution of anhydrous ethanol and non-ionic fluorocarbon surfactant is 6%.

[0116] The mass of the nonionic fluorocarbon surfactant in step (1) accounts for 0.08% of the total mass of anhydrous ethanol and the nonionic fluorocarbon surfactant. The nonionic fluorocarbon surfactant is Capstone-FS-31, and the manufacturer is DuPont China Group Co., Ltd. Shanghai Branch.

[0117] The mass of α,α-diethoxyacetophenone in step (1) accounts for 0.2% of the mass of 2-hydroxyethyl methacrylate phosphate.

[0118] In step (1), the UV curing temperature is room temperature and the UV curing time is 7 minutes.

[0119] The polytetrafluoroethylene-based base film described in step (1) is manufactured by Shandong Senrong New Materials Co., Ltd., and the model number is SRM001-03.

[0120] The manufacturer of the perfluorosulfonic acid resin solution in step (2) is Chemours Chemical (Shanghai) Co., Ltd., the model is Nafion D2020, and the mass fraction is 20%.

[0121] The mass ratio of the perfluorosulfonic acid resin solution to N-methylpyrrolidone in step (2) is 1:0.088.

[0122] In step (3), the heat treatment is first performed at 104°C for 1.25 h and then at 137°C for 16 min.

[0123] The post-treatment in step (3) is to cool the glass plate to room temperature after the heat treatment is completed, and then peel the film off the glass plate.

[0124] The performance of the composite enhanced perfluorosulfonic acid proton exchange membranes prepared in Examples 1-3 and Comparative Examples 1-3 was tested, and the results are shown in Table 1 below:

[0125] Table 1 Performance test results of composite enhanced perfluorosulfonic acid proton exchange membrane

[0126]

Claims

1. A process for preparing a composite enhanced perfluorosulfonic acid proton exchange membrane, characterized in that: It consists of the following steps: (1) 2-hydroxyethyl methacrylate phosphate is added to a mixture of anhydrous ethanol and a nonionic fluorocarbon surfactant, and then α,α-diethoxyacetophenone is added and stirred evenly to prepare a mixed solution, a polytetrafluoroethylene-based base film is immersed in the mixed solution for 30-40 minutes, and after taking it out, the mixed solution is evenly coated on the polytetrafluoroethylene-based base film using a coater, and finally ultraviolet light curing is performed to prepare a first polytetrafluoroethylene-based base film; (2) adding the perfluorosulfonic acid resin solution to a mixture of 2-hydroxyethylammonium formate and N-methylpyrrolidone and reacting at a constant temperature of 83-85°C for 48-50 hours to prepare a membrane-forming solution; (3) The membrane-forming liquid prepared in step (2) is coated on a glass plate, and then the first polytetrafluoroethylene-based base film is evenly covered on the membrane-forming liquid, and then the membrane-forming liquid is coated again on the first polytetrafluoroethylene-based base film. Finally, after heat treatment and post-treatment, a composite enhanced perfluorosulfonic acid proton exchange membrane is prepared.

2. The process for preparing the composite enhanced perfluorosulfonic acid proton exchange membrane according to claim 1, characterized in that: In step (1), the mass concentration of 2-hydroxyethyl methacrylate phosphate in the mixed solution of anhydrous ethanol and non-ionic fluorocarbon surfactant is 5-7%.

3. The process for preparing the composite enhanced perfluorosulfonic acid proton exchange membrane according to claim 1, characterized in that: The mass of the nonionic fluorocarbon surfactant in step (1) accounts for 0.08% of the total mass of anhydrous ethanol and the nonionic fluorocarbon surfactant, and the nonionic fluorocarbon surfactant is Capstone-FS-31.

4. The process for preparing the composite enhanced perfluorosulfonic acid proton exchange membrane according to claim 1, characterized in that: The mass of α,α-diethoxyacetophenone in step (1) accounts for 0.2% of the mass of 2-hydroxyethyl methacrylate phosphate.

5. The process for preparing the composite enhanced perfluorosulfonic acid proton exchange membrane according to claim 1, characterized in that: In step (1), the UV curing temperature is room temperature, and the UV curing time is 6-8 minutes.

6. The process for preparing the composite enhanced perfluorosulfonic acid proton exchange membrane according to claim 1, characterized in that: The model of the perfluorosulfonic acid resin solution in step (2) is Nafion D2020, and the mass fraction is 20%.

7. The process for preparing a composite enhanced perfluorosulfonic acid proton exchange membrane according to claim 1, characterized in that: In step (2), the 2-hydroxyethyl ammonium formate is an aqueous solution of 2-hydroxyethyl ammonium formate, and the mass fraction of the 2-hydroxyethyl ammonium formate solution is 13-15%.

8. The process for preparing a composite enhanced perfluorosulfonic acid proton exchange membrane according to claim 1, characterized in that: The volume percentage of 2-hydroxyethylammonium formate and N-methylpyrrolidone in the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone in step (2) is 0.45:0.

55.

9. The process for preparing a composite enhanced perfluorosulfonic acid proton exchange membrane according to claim 1, characterized in that: In step (2), the mass ratio of the perfluorosulfonic acid resin solution to the mixed solution of 2-hydroxyethylammonium formate and N-methylpyrrolidone is 1:0.075-0.

10.

10. The process for preparing a composite enhanced perfluorosulfonic acid proton exchange membrane according to claim 1, characterized in that: In step (3), the heat treatment is first performed at 103-105° C. for 1.2-1.3 h, and then at 135-138° C. for 15-18 min; The post-treatment in step (3) is to cool the glass plate to room temperature after the heat treatment is completed, and then peel the film off the glass plate.

Images