CN114634682A

CN114634682A - Polar polymer/sulfonated polyarylether polymer composite, ion exchange membrane and preparation method thereof

Info

Publication number: CN114634682A
Application number: CN202210397344.5A
Authority: CN
Inventors: 董天都; 刘昊; 张泽天; 李蕴熙; 鹿传睿; 贾雯迪; 杨云菲
Original assignee: Spic Hydrogen Energy Technology Development Co Ltd
Current assignee: Spic Hydrogen Energy Technology Development Co Ltd
Priority date: 2022-04-15
Filing date: 2022-04-15
Publication date: 2022-06-17

Abstract

The invention provides a polar polymer/sulfonated polyarylether polymer compound, an ion exchange membrane and a preparation method thereof. The polar polymer/sulfonated polyarylether polymer compound comprises a polar polymer and a sulfonated polyarylether polymer, wherein the mass content of the polar polymer is 0.1-95%; the polar polymer has a water absorption of less than 30% at 25 ℃ and is water insoluble. By introducing the polar polymer with low water absorption, the water absorption of the composite can be effectively reduced, and the problems of high swelling, membrane size stability, physical and mechanical properties, chemical stability and poor barrier property caused by overhigh water absorption of the sulfonated polyarylether polymer are solved.

Description

Polar polymer/sulfonated polyarylether polymer composite, ion exchange membrane and preparation method thereof

Technical Field

The invention relates to the technical field of high molecular materials, in particular to a polar polymer/sulfonated polyarylether polymer composite, an ion exchange membrane and a preparation method thereof.

Background

The ion exchange membrane is widely applied to the fields of fuel cells, chlor-alkali industry, flow batteries, water electrolysis hydrogen production, membrane separation technology, protective materials and the like. The good comprehensive performance of the perfluorinated sulfonic acid resin makes the perfluorinated sulfonic acid resin become the most successful material applied to an ion exchange membrane. However, the fluorine-containing material has high cost, the production process is not environment-friendly, and the non-fluorine proton exchange membrane is always a research hotspot. In past research, the substrate selected for the non-fluorine proton exchange membrane is mainly aromatic polymer containing benzene ring or polymer containing functional groups such as hydroxyl, amino, chloromethyl and carboxyl. Other polymer matrices, such as oxygenated aliphatic hydrocarbon polymers, polycarbonates, and polyolefin materials, can also be used to prepare proton exchange membranes, but are less studied and have less than desirable properties. Therefore, the main research direction at present is still the aromatic polymer proton exchange membrane material, and the polyarylether polymers are researched most and most deeply.

The polyarylether polymers comprise polyarylether sulphone, polyarylether nitrile, polyether sulfone, polyetheretherketone and derivatives thereof, and have the advantages of good mechanical property, oxidation resistance, acid-resistant catalytic hydrolysis performance, low manufacturing cost, low carbon hydrogen fuel permeability and good film forming property. Hydrophilic groups (mainly sulfonic acid groups) are connected to the main chain of the polymer, so that the hydrophilic performance of the polymer is improved, and the polymer can be applied to an ion exchange membrane. In addition to using sulfonation reagents such as concentrated sulfuric acid, chlorosulfonic acid, acylsulfonic acid and the like to sulfonate and modify the positions of benzene rings of the polyarylether polymers, the sulfonated polyarylether polymers with more definite structures and sulfonation degrees can also be obtained by directly polymerizing monomers containing sulfonic acid groups. In order to improve the stability of sulfonic acid group on benzene ring and prevent side reaction and degradation reaction, the improvement method is mainly to graft rigid aryl sulfonic acid side chain or alkyl sulfonic acid, fluoroalkyl sulfonic acid side chain on main chain benzene ring. The other limitation of the ion exchange membrane performance of the polyarylether base material is mainly the poor dimensional stability and large swelling degree of the high sulfonation degree polymer material, and the high sulfonation degree polymer material is easy to dissolve in water. The hydrophilicity of the membrane can be well controlled by crosslinking the sulfonated polymer or designing different main chain structures and grafting different types of side chains, but the crosslinking structure is difficult to realize in the aspect of process and is not beneficial to the recovery of the catalyst, so that the membrane is difficult to be applied on a large scale on a production line. Meanwhile, in the process of preparing the membrane electrode, the cross-linked polymer serving as polyelectrolyte cannot be dispersed in the catalyst slurry, which is not beneficial to the preparation of the membrane electrode.

In the prior art, the ion transmission capability of the random copolymerization type sulfonated polyaryletherketone ion exchange membrane depends on the improvement of the content of sulfonic acid groups, but the water absorption of the ion exchange membrane is increased rapidly along with the improvement of the sulfonation degree and IEC, so that the size stability, the physical and mechanical properties, the chemical stability and the barrier property of the membrane are reduced rapidly. The defect limits the application of the sulfonated polyaryletherketone in high-humidity working conditions of fuel cell proton exchange membranes, electrodialysis membranes, water electrolysis membranes and the like. The sulfonated polyaryletherketone ion exchange membrane prepared by covalent bond crosslinking effectively overcomes a series of problems caused by overhigh water absorption, but the crosslinking structure process is difficult to realize and is not beneficial to recovery, and the crosslinking polymer is difficult to be used as polyelectrolyte of catalyst slurry.

Disclosure of Invention

The invention mainly aims to provide a polar polymer/sulfonated polyarylether polymer compound, an ion exchange membrane and a preparation method thereof, and aims to solve the problems of poor membrane size stability, physical and mechanical properties, chemical stability and barrier property in polyarylether ion exchange membranes in the prior art.

In order to achieve the above object, according to one aspect of the present invention, there is provided a polar polymer/sulfonated polyarylether polymer composite, comprising a polar polymer and a sulfonated polyarylether polymer, wherein the polar polymer is 0.1-95% by mass; the polar polymer has a water absorption of less than 30% at 25 ℃ and is water insoluble.

Further, the polar group of the polar polymer is selected from any one or more of nitrile group, phenolic hydroxyl group, alcoholic hydroxyl group, phosphate group, phosphite group or imide ring, preferably the polar polymer comprises any one or more of polyphosphate ester, polyphosphate ester block copolymer, polyurethane, polyamino phosphate ester, amino phosphite ester polymer, ethylene-vinyl alcohol copolymer and polyimide.

Further, the polyphosphate ester block copolymer comprises a diblock copolymer or a triblock copolymer formed by phosphate and at least one of ethylene glycol, ethylene glycol monomethyl ether, caprolactone or propylene; preferably, the ethylene molar content of the ethylene-vinyl alcohol copolymer is 25-60%, the alcoholysis degree is not less than 95%, and the melt index of the ethylene-vinyl alcohol copolymer is 2.2-15.2 g/10min, preferably 2.7-14.7 g/10min, and more preferably 2.9-13.9 g/10 min; preferably the polyimide is a soluble polyimide.

Further, the sulfonated polyarylether polymer has a structure represented by formula I:

wherein m is 1-20, and n is 1-10;

Ar₁represents

One or more of;

Ar₂represents

One or more of;

Ar₃represents

One or more of (a).

Further, the sulfonated polyarylether polymer is

One or more of (a).

Further, the polar polymer is selected from

Wherein, a ranges from 1 to 30, b ranges from 5 to 25, x ranges from 1 to 20, y ranges from 3 to 22, z ranges from 20 to 35, p ranges from 15 to 20, f ranges from 1 to 10, g ranges from 1 to 15, h ranges from 4 to 28, and c ranges from 8 to 21.

Furthermore, in the polar polymer/sulfonated polyarylether polymer composite, the mass content of the polar polymer is 1-90%, preferably 1.5-85%.

In order to achieve the above object, according to one aspect of the present invention, there is provided an ion exchange membrane comprising the above polar polymer/sulfonated polyarylether polymer composite.

According to another aspect of the present invention, there is provided a method for preparing the ion exchange membrane, the method comprising: dissolving and dispersing the polar polymer/sulfonated polyarylether polymer composite in an organic medium to obtain a composite dispersion liquid; and preparing the composite dispersion liquid into a wet film, and drying to obtain the ion exchange membrane.

Further, the organic medium is at least one selected from dimethyl sulfoxide, N dimethylformamide, N dimethylacetamide and N-methylpyrrolidone.

Further, the drying temperature is 70-90 ℃, and the drying time is 24-36 h.

By applying the technical scheme of the invention, the water absorption of the composite can be effectively reduced by introducing the polar polymer with low water absorption, and the problems of high swelling, membrane size stability, physical and mechanical properties, chemical stability and barrier property reduction caused by high water absorption of the sulfonated polyarylether polymer are solved. If the content of the polar polymer is too high, the conductivity and the water absorption rate are affected; if the polar polymer content is too low, the physical and chemical stability of the film may be lowered. Therefore, the hydrophilicity of the composite can be effectively regulated and controlled by adjusting the ratio of the polar polymer to the sulfonated polyarylether polymer, and a proper water absorption rate is designed as required. Meanwhile, the polar group in the polar polymer and the sulfonic acid group in the sulfonated polyarylether polymer have hydrogen bonding effect, and the formed three-dimensional hydrogen bonding network is beneficial to ion transmission, so that the ion transmission efficiency is improved on the basis of not improving the sulfonation degree, and the mechanical property, the chemical stability and the barrier property of the material are improved by controlling the sulfonation degree. Meanwhile, under the action of the hydrogen bond, the polar polymer and the sulfonated polyarylether polymer can be uniformly mixed, thereby being beneficial to preparing the polymer membrane. The polar polymer/sulfonated polyarylether polymer composite is a non-covalent bond crosslinking structure, the structure enables the composite to be conveniently dissolved and dispersed by a solvent, and the solubility is beneficial to the recovery of the composite and products thereof and the preparation of catalyst slurry and membrane electrodes. The polar polymer/sulfonated polyarylether polymer compound solves the problem that the water absorption of the sulfonated polyarylether polymer is too high, overcomes the problem that a covalent bond crosslinking type sulfonated polyarylether compound crosslinking process is difficult to realize, and can be used for preparing a high-performance non-crosslinking type ion exchange membrane.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 shows the conductivity of ion exchange membranes at 95% RH at various temperatures in examples 7-9 of the present invention;

FIG. 2 shows the conductivity of the ion-exchange membranes of examples 13-18 of the present invention at 95% RH at various temperatures;

FIG. 3 shows the polarization curves of the ion-exchange membranes at 80 ℃ and 95% RH in examples 13 and 18 of the present invention;

FIG. 4 shows the polarization curve of the ion-exchange membrane of comparative example 5 of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

As analyzed by the background technology of the application, the prior art has the problems of poor membrane size stability, poor physical and mechanical properties, poor chemical stability and poor barrier property in the polyarylether ion exchange membrane. In order to solve the problems, the application provides a polar polymer/sulfonated polyarylether polymer composite, an ion exchange membrane and a preparation method thereof.

In a typical embodiment of the present application, a polar polymer/sulfonated polyarylether polymer composite is provided, which comprises a polar polymer and a sulfonated polyarylether polymer, wherein the mass content of the polar polymer is 0.1-95%; the polar polymer has a water absorption of less than 30% at 25 ℃ and is water insoluble.

By introducing the polar polymer with low water absorption, the water absorption of the composite can be effectively reduced, and the problems of high swelling, membrane size stability, physical and mechanical properties, chemical stability and barrier property reduction caused by high water absorption of the sulfonated polyarylether polymer are solved. If the content of the polar polymer is too high, the conductivity and the water absorption rate are affected; if the polar polymer content is too low, the physical and chemical stability of the film may be lowered. Therefore, the hydrophilicity of the composite can be effectively regulated and controlled by adjusting the ratio between the polar polymer and the sulfonated polyarylether polymer, and a proper water absorption rate is designed according to needs. Meanwhile, the polar group in the polar polymer and the sulfonic acid group in the sulfonated polyarylether polymer have hydrogen bonding effect, and the formed three-dimensional hydrogen bonding network is beneficial to ion transmission, so that the ion transmission efficiency is improved on the basis of not improving the sulfonation degree, and the mechanical property, the chemical stability and the barrier property of the material are improved by controlling the sulfonation degree. Meanwhile, under the action of the hydrogen bond, the polar polymer and the sulfonated polyarylether polymer can be uniformly mixed, thereby being beneficial to preparing the polymer membrane. The polar polymer/sulfonated polyarylether polymer composite is a non-covalent bond crosslinking structure, the structure enables the composite to be conveniently dissolved and dispersed by a solvent, and the solubility is beneficial to the recovery of the composite and products thereof and the preparation of catalyst slurry and membrane electrodes. The polar polymer/sulfonated polyarylether polymer compound solves the problem that the water absorption of the sulfonated polyarylether polymer is too high, overcomes the problem that a covalent bond crosslinking type sulfonated polyarylether compound crosslinking process is difficult to realize, and can be used for preparing a high-performance non-crosslinking type ion exchange membrane.

The composite improves the water absorption rate and mechanical property under high humidity condition, so the composite can be applied to diaphragms in chlor-alkali industry, polyelectrolyte membranes for hydrogen production by water electrolysis, separation membranes, membrane reactors and humidity sensors.

In order to enable the composite to have a suitable water absorption, the water absorption of the polar polymer should not be too high; meanwhile, in order to form more stable hydrogen bonding with the sulfonic acid group of the sulfonated polyarylether polymer, in some embodiments, it is preferable that the polar group of the polar polymer is selected from any one or more of nitrile group, phenolic hydroxyl group, alcoholic hydroxyl group, phosphate group, phosphite group, or imide ring. The polar polymers having the polar groups capable of realizing the functions can be various, and in order to improve the synergistic composite effect of the polar polymers and the sulfonated polyarylether polymers and better meet the functional requirements of the ion exchange membrane, the polar polymers preferably comprise one or more of polyphosphate, polyphosphate block copolymers, polyurethanes, polyamino phosphate, amino phosphite polymers, ethylene-vinyl alcohol copolymers and polyimides. Preferably, the polyphosphate block copolymer is phosphate and at least one of ethylene glycol, ethylene glycol monomethyl ether, caprolactone or propyleneTo form a diblock copolymer or a triblock copolymer; the ethylene-vinyl alcohol copolymer can be an ethylene-vinyl alcohol copolymer commonly used in the prior art, and according to different degrees of saponification and alcoholysis, the ethylene molar content of the ethylene-vinyl alcohol copolymer is preferably 25-60%, the alcoholysis degree is not less than 95%, the melt index of the ethylene-vinyl alcohol copolymer is preferably 2.2-15.2 g/10min, preferably 2.7-14.7 g/10min, and more preferably 2.9-13.9 g/10 min; the polyimide is soluble polyimide, the application can improve the solubility by introducing flexible groups such as ether bond, siloxane bond, carbonyl, sulfuryl, isopropylidene and alkyl group into the main chain of the polyimide, and/or introducing large side groups such as tert-butyl, benzene ring, trifluoromethyl and the like into the main chain, and/or introducing fluorine-containing groups into the main chain, preferably the polyimide is fluorine-containing group of the main chain, and/or the main chain contains ether bond, and/or the main chain introduces trifluoromethyl, for example

The value of c is in the range of 8-15, preferably c is 15, 12 or 8.

In order to make the compound have good mechanical property and obtain good film-forming property, the sulfonated polyarylether compound with higher sulfonation degree is selected. In some embodiments, the sulfonated polyarylether polymer has a structure according to formula I:

wherein m is 1-20, n is 1-10, and the sulfonation degree is ensured to be 70% -100%;

Ar₁represents

Ar₂Represents

Ar₃Represents

In some embodiments, the sulfonated polyarylether polymer is:

one or more of (a).

The ion transmission capability of the polar polymer is negligible, but the hydrogen bonding action of the polar group and the sulfonic acid group of the polar polymer can effectively improve the material performance. In some embodiments, the polar polymer is selected from

The polar polymer and the sulfonated polyarylether polymer can be blended in any proportion to obtain the compound, and the water absorption of the compound can be regulated and controlled by changing the mass content of the polar polymer in the compound, so that the hydrophilicity of the compound can be regulated and controlled. In some embodiments, the polar polymer/sulfonated polyarylether polymer composite contains 1% to 90% by weight of the polar polymer, preferably 1.5% to 85%. The mass content of the polar polymer is controlled within the range, so that relatively stable physical and chemical properties and relatively high conductivity can be maintained.

In another exemplary embodiment of the present application, there is provided an ion exchange membrane comprising the above polar polymer/sulfonated polyarylether polymer composite.

The ion exchange membrane with the polar polymer/sulfonated polyarylether polymer composite can reduce water absorption and Ion Exchange Capacity (IEC), but the physical cross-linking structure among molecules improves proton transmission capability, so that the ion exchange membrane has higher proton conductivity, thereby solving the problems of high swelling, membrane dimensional stability, physical and mechanical properties, chemical stability and barrier property reduction caused by high water absorption.

In another exemplary embodiment of the present application, there is provided a method for preparing the above ion exchange membrane, the method comprising: dissolving and dispersing the polar polymer/sulfonated polyarylether polymer composite in an organic medium to obtain a composite dispersion liquid; and preparing the composite dispersion liquid into a wet film, and drying to obtain the ion exchange membrane.

Due to the solubility of the polar polymer/sulfonated polyarylether polymer composite, the composite can be dissolved and dispersed in an organic medium to obtain a composite dispersion liquid, and then the ion exchange membrane is prepared by utilizing the dispersion liquid. The method has the advantages of mild reaction conditions, simplicity and easiness in implementation. The ion exchange membrane with the polar polymer/sulfonated polyarylether polymer composite can reduce water absorption and Ion Exchange Capacity (IEC), but the physical cross-linking structure among molecules improves proton transmission capability, so that the ion exchange membrane has higher proton conductivity, thereby solving the problems of high swelling, membrane dimensional stability, physical and mechanical properties, chemical stability and barrier property reduction caused by high water absorption.

The prior art methods of forming the composite dispersion into a wet film are applicable to this application. In some embodiments, the wet film may be prepared by casting, coating, or casting.

In order to enable the compound to be completely dissolved and dispersed in the organic medium, the mass ratio of the compound to the organic medium is controlled to be 50: 1-4: 1.

The kind of the organic medium is not particularly limited, and any organic medium commonly used in the art may be used in the present application. In some embodiments, the organic medium is selected from at least one of dimethylsulfoxide, N dimethylformamide, N dimethylacetamide, or N-methylpyrrolidone.

In order to evaporate the organic medium and not destroy the structure of the ion exchange membrane, in some embodiments, the drying temperature is 70-90 ℃ and the drying time is 24-36 h.

The present application is described in further detail below with reference to specific examples, which should not be construed as limiting the scope of the invention as claimed.

The phosphate copolymer is prepared in a laboratory, and the preparation method of the copolymer comprises the following steps: styrene-terminated polypropylene is used as an initiator, the polypropylene terminated by benzyl bromide groups is obtained through the Ma's addition reaction, and the phosphate copolymer is synthesized through atom transfer radical polymerization of 4-vinyl benzyl diethyl phosphonate.

The structural formula of the polyphosphate diblock copolymer used in the examples of the application is

Wherein, a is 1200, b is 300.

It should be noted that the polar group in the present application may have weak acidity or weak basicity, but other groups than partial phosphate and phosphite do not have ion exchange ability like carboxylic acid, sulfonic acid, phosphoric acid, quaternary ammonium, azonium, etc. The reason why part of the phosphates and phosphites has IEC is that there may be a case where P-OH bonds coexist with P-O-C in the functional groups, and when P-OH bonds in the functional groups are not substantially different from P-OH bonds in phosphoric acid, they have ion exchange ability and can be characterized by IEC values.

The polyphosphate diblock copolymer has only P-O-C bonds and no P-OH bonds, so that the copolymer has no IEC.

The structural formula of the polyphosphate triblock copolymer prepared by ring-opening copolymerization is shown as

Wherein x is 23, y is 16, z is 15, p is 3, and IEC is 0.39 mmol/g.

Polyphosphoramidates (PAPEs), which are compounds known in the art and are either synthesized according to methods known in the art or are commercially available. The structural formula of the PAPE is

Wherein d is 25. PAPE has no IEC.

The structural formula of the amino phosphite ester polymer synthesized by the aqueous solution of ethylenediamine and hypophosphorous acid under the acidic condition (pH is 1) is shown in the specification

Where e ═ 27, the IEC of the aminophosphite polymer was 2.2 mmol/g.

The structural formula of the ethylene-vinyl alcohol copolymer (EVOH) is shown in the specification

Wherein the ethylene molar content is f/(f + g + h) × 100%; degree of alcoholysis g/(g + h) × 100%. Wherein the f accounts for the ethylene molar content, the h accounts for the alcoholysis degree (saponification degree), and the melt index of the polymer is 2.2-15.2 g/10 min. The EVOH used in the examples of the present application is shown in table 1.

TABLE 1

The soluble polyimide prepared by stepwise polymerization has the structural formula

Wherein c is 15.

The structural formula of the sulfonated polyether ether ketone (SPAEK-1) is shown in the specification

The polymer had an IEC of 1.86mmol/g and was obtained by polymerizing 4, 4-difluorobenzophenone, hexafluorobisphenol A and methoxyhydroquinone at 170 ℃.

The structural formula of the sulfonated polyether ether ketone (SPAEK-2) is shown in the specification

The IEC of this polymer was 1.91 mmol/g.

The sulfonated polyether ether ketone (SPAEK-3) has a structural formula of

The IEC of this polymer was 1.85 mmol/g.

The Sulfonated Polyarylethersulfone (SPAES) has a structural formula of

The IEC of the polymer was 1.79mmol/g and was obtained by polymerizing 4, 4-difluorodiphenylsulfone, hexafluorobisphenol A and methoxyhydroquinone at 170 ℃.

The structural formula of the Sulfonated Polyarylethernitrile (SPAEN) is shown in the specification

The IEC of the polymer was 1.83mmol/g and was obtained by polymerizing 2, 6-difluorobenzonitrile, hexafluorobisphenol A and methoxyhydroquinone at 170 ℃.

The Sulfonated Polyaryletherketone (SPAEK) has a structural formula

The IEC of this polymer was 1.82 mmol/g.

Example 1

Dissolving and dispersing 0.3 mass part of polyphosphoric acid diblock copolymer and 0.7 mass part of sulfonated polyether ether ketone (SPAEK-1) in 9 mass parts of N, N-dimethylacetamide (DMAc) to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 24h to obtain the non-crosslinked ion exchange membrane (M-1).

Example 2

Dissolving and dispersing 0.3 part by mass of polyphosphate triblock copolymer and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-1) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 24h to obtain the non-crosslinked ion exchange membrane (M-2).

Example 3

Dissolving and dispersing 0.3 part by mass of polyamino phosphate (PAPE) and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-1) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a compound dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 24h to obtain the non-crosslinked ion exchange membrane (M-3).

Example 4

Dissolving and dispersing 0.3 part by mass of an amino phosphite polymer and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-1) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 24h to obtain the non-crosslinked ion exchange membrane (M-4).

Example 5

Dissolving and dispersing 0.3 part by mass of ethylene-vinyl alcohol copolymer (EVOH-1) and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-1) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a composite dispersion liquid; and (3) casting the compound dispersion liquid in an ultra-flat die, and drying at 80 ℃ for 24 hours to obtain the non-crosslinked ion exchange membrane (M-5).

Example 6

Dissolving and dispersing 0.3 part by mass of soluble polyimide and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-1) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 24h to obtain the non-crosslinked ion exchange membrane (M-6).

The performance of the ion-exchange membranes prepared in examples 1-6 is shown in table 2, wherein the temperature for the conductivity test is 80 ℃ and the humidity is 95% RH (relative humidity).

TABLE 2

Example 7

Dissolving and dispersing 0.3 part by mass of soluble polyimide and 0.7 part by mass of Sulfonated Polyarylethersulfone (SPAES) in 9 parts by mass of DMSO to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 36h to obtain the non-crosslinked ion exchange membrane (M-7).

Example 8

Dissolving and dispersing 0.3 part by mass of soluble polyimide and 0.7 part by mass of sulfonated polyaryl ether nitrile (SPAEN) in 9 parts by mass of DMSO (dimethylsulfoxide) to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 36h to obtain the non-crosslinked ion exchange membrane (M-8).

Example 9

Dissolving and dispersing 0.3 part by mass of soluble polyimide and 0.7 part by mass of Sulfonated Polyaryletherketone (SPAEK) in 9 parts by mass of DMSO (dimethylsulfoxide) to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 36h to obtain the non-crosslinked ion exchange membrane (M-9).

The performance of the ion-exchange membranes prepared in examples 7 to 9 is shown in table 3, in which the conductivity data are 80 ℃ and 95% RH, and the conductivity at different temperatures and 95% RH is shown in fig. 1.

TABLE 3

Example 10

Dissolving and dispersing 0.01 part by mass of polyaminophosphate (PAPE) and 0.99 part by mass of sulfonated polyether ether ketone (SPAEK-1) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 24h to obtain the non-crosslinked ion exchange membrane (M-10).

Example 11

Dissolving and dispersing 0.5 part by mass of polyaminophosphate (PAPE) and 0.5 part by mass of sulfonated polyether ether ketone (SPAEK-1) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 24h to obtain the non-crosslinked ion exchange membrane (M-11).

Example 12

Dissolving and dispersing 0.95 parts by mass of polyamino phosphate (PAPE) and 0.05 parts by mass of sulfonated polyether ether ketone (SPAEK-1) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a composite dispersion liquid; and (3) casting the compound dispersion liquid in an ultra-flat die, and drying at 80 ℃ for 24 hours to obtain the non-crosslinked ion exchange membrane (M-12).

The performance of the ion exchange membranes prepared in examples 10-12 is shown in Table 4, wherein the conductivity data is measured at 80 ℃ and 95% RH.

TABLE 4

Since the PAPE itself has low strength and high toughness, but when the PAPE is blended with SPAEK-1, the PAPE and the SPEEK act synergistically to enhance toughening, the best effect is obtained in example 10. The synergistic effect was poor with less PAPE in example 10 and less SPAEK-1 in example 12.

Example 13

Dissolving and dispersing 0.3 part by mass of EVOH-2 and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-3) in 9 parts by mass of DMF to obtain a composite dispersion liquid; and (3) casting the compound dispersion liquid in an ultra-flat die, and drying at 80 ℃ for 12h to obtain the non-crosslinked ion exchange membrane (M-13).

Example 14

Dissolving and dispersing 0.3 part by mass of EVOH-3 and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-3) in 9 parts by mass of DMF to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 12h to obtain the non-crosslinked ion exchange membrane (M-14).

Example 15

Dissolving and dispersing 0.3 part by mass of EVOH-4 and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-3) in 9 parts by mass of DMF to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 12h to obtain the non-crosslinked ion exchange membrane (M-15).

Example 16

Dissolving and dispersing 0.3 part by mass of EVOH-5 and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-3) in 9 parts by mass of DMF to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 12h to obtain the non-crosslinked ion exchange membrane (M-16).

Example 17

Dissolving and dispersing 0.3 part by mass of EVOH-6 and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-3) in 9 parts by mass of DMF to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 12h to obtain the non-crosslinked ion exchange membrane (M-17).

Example 18

Dissolving and dispersing 0.3 part by mass of EVOH-7 and 0.7 part by mass of sulfonated polyether ether ketone (SPAEK-3) in 9 parts by mass of DMF to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 12h to obtain the non-crosslinked ion exchange membrane (M-18).

The performance of the ion exchange membranes prepared in examples 13-18 is shown in Table 5, wherein the conductivity data is measured at 80 ℃ and 95% RH. The conductivity at 95% RH and different temperatures of the ion-exchange membranes prepared in examples 13-18 is shown in figure 2. The polarization curves of the ion-exchange membranes of example 13 and example 18 at 80 ℃ and 95% RH are shown in the figure3, respectively. The ion exchange membranes M-13 and M-18 had a hydrogen permeation current density of 1.27mA/cm²And 1.75mA/cm²。

TABLE 5

Example 19

Dissolving and dispersing 0.95 parts by mass of polyamino phosphate (PAPE) and 0.05 parts by mass of sulfonated polyether ether ketone (SPAEK-2) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 24h to obtain the non-crosslinked ion exchange membrane (M-19). The IEC of the M-19 is 0.09mmol/g, the water absorption is 15.0%, the conductivity is 0.006S/cm, the tensile strength is 41MPa, and the elongation at break is 73.2%.

Example 20

Dissolving and dispersing 0.001 part by mass of polyaminophosphate (PAPE) and 0.999 part by mass of sulfonated polyether ether ketone (SPAEK-1) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a composite dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 24h to obtain the non-crosslinked ion exchange membrane (M-20). The IEC of the M-20 is 1.82mmol/g, the water absorption is 47.0%, the conductivity is 0.147S/cm, the tensile strength is 50MPa, and the elongation at break is 34.5%.

Comparative example 1

Dissolving and dispersing 1 part by mass of sulfonated polyether ether ketone (SPAEK-1) in 9 parts by mass of N, N-dimethylacetamide (DMAc) to obtain a polymer dispersion liquid; and (3) casting the polymer dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 24 hours to obtain the ion exchange membrane (DM-1).

The IEC of DM-1 is 1.69mmol/g, the water absorption is 65.0%, the conductivity is 0.139S/cm, the tensile strength is 48MPa, and the elongation at break is 21.9%. Compared with the ion exchange membranes in examples 1-3 and 5, the introduction of the polar polymer improves the conductivity and enhances the toughness. In example 5, the EVOH is introduced to comprehensively improve the performance of the ion exchange membrane; compared with DM-1, the ion exchange membrane of example 5 has the advantages of tensile strength improvement of 42.5%, elongation at break improvement of about 477%, obvious mechanical property improvement, and conductivity improvement of about 22% at 80 ℃. The introduction of the soluble polyimide increased the strength and decreased the water absorption compared to example 6. This is because the toughness of the soluble polyimide material itself is low.

Comparative example 2

Dissolving and dispersing 1 part by mass of Sulfonated Polyarylethersulfone (SPAES) in 9 parts by mass of DMSO to obtain a polymer dispersion liquid; and (3) casting the polymer dispersion liquid in an ultra-flat die, and drying at 80 ℃ for 36h to obtain the ion exchange membrane (DM-2).

Comparative example 3

Dissolving and dispersing 1 part by mass of sulfonated poly (arylene ether nitrile) (SPAEN) in 9 parts by mass of DMSO (dimethylsulfoxide) to obtain a polymer dispersion liquid; and (3) casting the polymer dispersion liquid in an ultra-flat die, and drying at 80 ℃ for 36h to obtain the ion exchange membrane (DM-3).

Comparative example 4

Dissolving and dispersing 1 part by mass of Sulfonated Polyaryletherketone (SPAEK) in 9 parts by mass of DMSO (dimethylsulfoxide) to obtain a compound dispersion liquid; and (3) casting the composite dispersion liquid in an ultra-flat mold, and drying at 80 ℃ for 36h to obtain the ion exchange membrane (DM-4).

Comparative examples 2-4 all showed more than 20% decrease in tensile strength compared to non-crosslinked ion exchange membranes prepared by blending the soluble polyimide with the sulfonated polyarylether polymer in examples 7-9.

Comparative example 5

Dissolving and dispersing 1 part by mass of sulfonated polyether ether ketone (SPAEK-3) in 9 parts by mass of DMF to obtain a polymer dispersion liquid; and (3) casting the polymer dispersion liquid in an ultra-flat die, and drying at 80 ℃ for 12h to obtain the ion exchange membrane (DM-5).

The IEC of the DM-5 was 1.86mmol/g, the water absorption was 58.4%, and the conductivity was 0.169 S.cm^-1Tensile strength of 55MPa, elongation at break of 25.5%, and hydrogen permeation current density of 2.64mA/cm²The polarization curve is shown in FIG. 4.

Compared with the non-crosslinked ion exchange membrane prepared by blending the EVOH and the SPAEK-3 in the examples 13-18, the conductivity is reduced by more than 6 percent, and the elongation at break is reduced by more than 50 percent. The conductivity decreased by about 14% compared to ion exchange membrane M-14.

The performance of the ion-exchange membranes of comparative examples 1-5 is shown in table 6, wherein the conductivity data is measured at 80 ℃ and 95% RH.

TABLE 6

Test method

The tensile properties were tested according to GB/T1040-.

The battery performance is as follows: cell performance includes cell polarization curve and hydrogen permeation current density. The performance of the single-chip cell is tested by adopting a fuel cell test bench and a GARY electrochemical workstation in the Dalianyuke department, and the test method refers to GB/T20042.5-2009 part 5 of proton exchange membrane fuel cell: membrane electrode test methods.

Conductivity: measuring the alternating current impedance of the film by adopting a Metrohm Autolab PGSTAT302N electrochemical workstation to calculate the proton conductivity, wherein the alternating current frequency is 1-10⁵Hz, scanning amplitude 10 mV. The film was clamped in a manner consistent with the four-electrode method.

And (4) IEC test: IEC values were determined for the polymers and films using a Titrino plus automated potentiometric titrator.

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects:

by introducing the polar polymer with low water absorption, the water absorption of the composite can be effectively reduced, and the problems of high swelling, membrane size stability, physical and mechanical properties, chemical stability and barrier property reduction caused by high water absorption are solved. By adjusting the proportion between the polar polymer and the sulfonated polyarylether polymer, the hydrophilicity of the compound can be effectively regulated and controlled, and the proper water absorption rate can be designed according to the requirement. Meanwhile, polar groups in the polar polymer and sulfonic acid groups in the sulfonated polyarylether polymer have hydrogen bonding effect, a formed three-dimensional hydrogen bonding network is favorable for ion transmission, the mechanical property of the material is improved, and the polar polymer and the sulfonated polyarylether polymer can be uniformly mixed under the action of the hydrogen bonding effect, so that the preparation of a polymer membrane is facilitated. The polar polymer/sulfonated polyarylether polymer composite is a non-covalent bond crosslinking structure, the structure enables the composite to be conveniently dissolved and dispersed by a solvent, and the solubility is beneficial to the recovery of the composite and products thereof and the preparation of catalyst slurry and membrane electrodes. The polar polymer/sulfonated polyarylether polymer compound solves the problem that the water absorption of the sulfonated polyarylether polymer is too high, overcomes the problem that a covalent bond crosslinking type sulfonated polyarylether compound crosslinking process is difficult to realize, and can be used for preparing a high-performance non-crosslinking type ion exchange membrane.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The polar polymer/sulfonated polyarylether polymer composite is characterized by comprising a polar polymer and a sulfonated polyarylether polymer, wherein the mass content of the polar polymer is 0.1-95%;

the polar polymer has a water absorption of less than 30% at 25 ℃ and is water insoluble.

2. A polar polymer/sulfonated polyarylether polymer composite according to claim 1, wherein the polar groups of the polar polymer are selected from any one or more of nitrile groups, phenolic hydroxyl groups, alcoholic hydroxyl groups, phosphate groups, phosphite groups or imide rings, preferably the polar polymer comprises any one or more of polyphosphate, polyphosphate block copolymer, polyurethane, polyaminophosphate, phosphoramidite polymer, ethylene-vinyl alcohol copolymer, polyimide;

preferably, the polyphosphate ester block copolymer comprises a diblock copolymer or a triblock copolymer formed by phosphate and at least one of ethylene glycol, ethylene glycol monomethyl ether, caprolactone or propylene; preferably, the ethylene molar content of the ethylene-vinyl alcohol copolymer is 25-60%, the alcoholysis degree is not less than 95%, and preferably, the melt index of the ethylene-vinyl alcohol copolymer is 2.2-15.2 g/10min, preferably 2.7-14.7 g/10min, and more preferably 2.9-13.9 g/10 min; preferably, the polyimide is a soluble polyimide.

3. The polar polymer/sulfonated polyarylether polymer composite of claim 1, wherein the sulfonated polyarylether polymer has a structure of formula I:

wherein m is 1-20, and n is 1-10;

Ar₁represents

One or more of (a);

Ar₂represents

One or more of (a);

Ar₃represents

One or more of (a).

4. The polar polymer/sulfonated polyarylether polymer composite of claim 1, wherein the sulfonated polyarylether polymer is a sulfonated polyarylether polymer

One or more of (a).

5. The polar polymer/sulfonated polyarylether polymer composite according to claim 1, wherein the polar polymer is selected from the group consisting of

Wherein, a ranges from 1 to 30, b ranges from 5 to 25, x ranges from 1 to 20, y ranges from 3 to 22, z ranges from 20 to 35, p ranges from 15 to 20, f ranges from 1 to 10, and g ranges from 1 to 15H is in the range of 4 to 28, and c is in the range of 8 to 21.

6. The polar polymer/sulfonated polyarylether polymer composite according to claim 1, wherein the mass content of the polar polymer in the polar polymer/sulfonated polyarylether polymer composite is 1-90%, preferably 1.5-85%.

7. An ion exchange membrane comprising the polar polymer/sulfonated polyarylether polymer composite of any of claims 1 to 6.

8. The method for preparing the ion exchange membrane according to claim 7, wherein the preparation method comprises the following steps:

dissolving and dispersing the polar polymer/sulfonated polyarylether polymer composite in an organic medium to obtain a composite dispersion liquid;

and preparing the composite dispersion liquid into a wet film and drying to obtain the ion exchange membrane.

9. The method according to claim 8, wherein the organic medium is at least one selected from the group consisting of dimethylsulfoxide, N-dimethylformamide, N-dimethylacetamide, and N-methylpyrrolidone.

10. The preparation method of claim 8, wherein the drying temperature is 70-90 ℃ and the drying time is 24-36 h.