Method for producing a membrane (M) containing a sulfonated polyarylene sulfone polymer (sP)

Abstract

The present invention relates to a process for the preparation of a membrane (M) containing a sulfonated polyarylenesulfone polymer (sP), to the membrane (M) obtainable by the process of the invention, to fuel cells, electrodialysis cells and electrolysis cells comprising said membrane, to the use of said membrane (M) in an electrolysis cell, an electrodialysis cell or a fuel cell, and to a process for the production of electrical energy and / or hydrogen.

Description

[Technical field]

[0001] The present invention relates to a process for the preparation of a membrane (M) containing a sulfonated polyarylenesulfone polymer (sP), to the membrane (M) obtainable by the process of the invention, to fuel cells, electrodialysis cells and electrolysis cells comprising said membrane, to the use of said membrane (M) in an electrolysis cell, an electrodialysis cell or a fuel cell, and to a process for the production of electrical energy and / or hydrogen. [Background technology]

[0002] Politics, society and industry aim to reduce CO2 emissions by decarbonizing industry and mobility. In this regard, green hydrogen plays a strategic role, since it can replace hydrocarbons for chemical and industrial processes, energy conversion and the propulsion of fuel cells in mobility applications. Renewable electricity can be used to run electrolysis cells to produce green and sustainable hydrogen.

[0003] The essential components in electrolysis cells, electrodialysis cells and fuel cells are the so-called polymer electrolyte membranes (PEM), which must fulfill several requirements: they must be ionically conductive, and at the same time they must separate the gases hydrogen and oxygen. Furthermore, the membranes must be robust and stable for long-term operation and lifetime at constant performance.

[0004] Prior art membranes are mainly based on fluorinated polymers with sulfonic acid side chains (PFSA), known for example under the trade name Nafion®. Due to the complexity of manufacturing PFSA, these polymers are still very expensive. Furthermore, the toxicity and persistence of fluorinated chemicals poses several problems for the manufacture, use and recycling of these materials. Therefore, science and industry are trying to develop more sustainable solutions to replace PFSA membranes.

[0005] One promising class of materials for these applications are polyarylenesulfone polymers, which belong to a group of high-performance polymers that have high heat resistance, chemical resistance, excellent mechanical properties, and durability (E.M. Koch, H.-M. Walter, Kunststoffe 80(1990)1146; E. Doering, Kunststoffe 80,(1990)1149; N. Inchaurondo-Nehm, Kunststoffe 98,(2008)190).

[0006] In addition to their use as engineering plastics, polyarylene sulfone polymers are also used as materials for membranes for water treatment.

[0007] Polyarylene sulfone polymers can be formed, inter alia, via the hydroxide process, in which a salt is first formed from a dihydroxy moiety and a hydroxide, or via the carbonate process.

[0008] General information regarding the formation of polyarylene sulfone polymers by the hydroxide method is found, inter alia, in RN Johnson et.al., J. Polym. Sci. A-15 (1967) 2375, while the carbonate method is described in JE McGrath et.al., Polymer 25 (1984) 1827.

[0009] Methods for forming polyarylene sulfone polymers from aromatic bishalogen compounds and aromatic bisphenols or their salts in aprotic solvents in the presence of one or more alkali metal or ammonium carbonates or bicarbonates are known to those skilled in the art and are described, for example, in EP-A 297363 and EP-A 135130.

[0010] High performance thermoplastics, such as polyarylene sulfone polymers, are formed by polycondensation reactions typically carried out at high reaction temperatures in polar aprotic solvents such as DMF (dimethylformamide), DMAc (dimethylacetamide), sulfolane, DMSO (dimethylsulfoxide) and NMP (N-methylpyrrolidone).

[0011] For use as a membrane material in water electrolysis cells, electrodialysis cells or fuel cells, the polymer must exhibit ionic conductivity, which can be achieved by functionalizing the polyarylene sulfone polymer with sulfonic acid groups.

[0012] Sulfonated polyarylene sulfone polymers have been known for many years. While direct sulfonation of polyarylene sulfone polymers leads to side reactions and allows only limited control of the degree of sulfonation, the use of disulfonated aromatic dihalogen sulfones, such as sulfonated dichlorodiphenyl sulfone (sDCDPS), as comonomers allows the synthesis of well-defined sulfonated polyarylene sulfone polymers.

[0013] Although sulfonated polyarylene sulfone polymers exhibit some interesting properties for use as ion-conducting membranes in fuel cells or for electrolysis cells, there is still room for improving the sulfonated polyarylene sulfone membranes described in the prior art in terms of proton conductivity, swelling and mechanical stability. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] European Patent Application Publication No. 297363 [Patent Document 2] European Patent Application Publication No. 135130 [Non-patent literature]

[0015] [Non-Patent Document 1] E.M.Koch, H.-M.Walter, Kunststoffe 80(1990)1146 [Non-Patent Document 2] E.Doering, Kunststoffe 80,(1990)1149 [Non-Patent Document 3] N.Inchaurondo-Nehm, Kunststoffe 98,(2008)190 [Non-Patent Document 4] RNJohnson et.al., J.Polym.Sci. A-15(1967)2375 [Non-Patent Document 5] JEMcGrath et.al., Polymer 25(1984)1827 Summary of the Invention [Problem to be solved by the invention]

[0016] The object of the present invention is therefore to provide a method for producing a membrane (M) containing a sulfonated polyarylenesulfone polymer (sP), which does not have the disadvantages of the prior art or only has them in a reduced form. The method should be easy to carry out. The membrane (M) containing a sulfonated polyarylenesulfone polymer (sP) should be suitable for use in electrolysis cells and fuel cells. Furthermore, the membrane (M) should be suitable for separating hydrogen from hydrogen-containing gas mixtures. [Means for solving the problem]

[0017] The subject of the present invention is a method for producing a membrane (M) containing a sulfonated polyarylenesulfone polymer (sP), comprising: i) an aromatic dihalogen sulfone component (component (A)) comprising at least one sulfonated aromatic dihalogen sulfone (component (A1)) and at least one non-sulfonated aromatic dihalogen sulfone (component (A2)); at least one aromatic dihydroxy compound (component (B)); at least one carbonate compound (component (C)), and At least one aprotic polar solvent (component (D)) The reaction mixture (R G ) to produce a product mixture (P) comprising a sulfonated polyarylene sulfone polymer (sP), at least one aprotic polar solvent, and at least one inorganic halide compound. G ), ii) adding said at least one inorganic halide to said product mixture (P G ) to obtain a solution (S) comprising a sulfonated polyarylene sulfone polymer (sP) and at least one aprotic polar solvent; iii) separating said at least one aprotic polar solvent from said solution (S) to obtain a membrane (M) containing a sulfonated polyarylenesulfone polymer (sP). The problem is solved by the method, which comprises:

[0018] Surprisingly, it has been found that the method of the present invention allows the production of membranes (M) that exhibit good proton conductivity, low swelling and high tensile elongation. The method of the present invention allows the production time of membranes (M) containing sulfonated polyarylenesulfone polymers (sP) to be significantly reduced. The condensation according to step i) leads to a polymer suspension containing the sulfonated polyarylenesulfone polymer (sP) and an inorganic halide salt. After separating the salt, the prior art usually performs a precipitation in isopropanol to isolate the sulfonated polyarylenesulfone polymer (sP), which results in a large amount of solvent mixture that must be reprocessed or disposed of.

[0019] Furthermore, some of the product may not completely precipitate, which may lead to clogging of the filters during the subsequent separation. Furthermore, the sulfonated copolymer must be dissolved again to produce the membrane (M). The method of the present invention avoids the generation of a large amount of solvent mixture and avoids separation before the production of the membrane.

[0020] The invention is described in more detail below.

[0021] method The method of the present invention for producing a membrane (M) containing a sulfonated polyarylene sulfone polymer (sP) comprises steps i), ii) and iii).

[0022] Stage i) In step i) according to the present invention, a reaction mixture (R 2 ) is prepared comprising an aromatic dihalogen sulfone component, at least one aromatic dihydroxy compound, at least one carbonate compound, and at least one aprotic polar solvent. G ) to produce a product mixture (P) comprising a sulfonated polyarylene sulfone polymer (sP), at least one aprotic polar solvent, and at least one inorganic halide compound. G ) is obtained.

[0023] The aromatic dihalogen sulfone component is also referred to as component (A). In the present invention, the terms aromatic dihalogen sulfone component and component (A) are used synonymously and therefore have the same meaning.

[0024] The at least one aromatic dihydroxy compound is also referred to as component (B). The terms at least one aromatic dihydroxy compound and component (B) in the present invention are used synonymously and therefore have the same meaning.

[0025] The at least one carbonate compound is also referred to as component (C). In the present invention, the terms at least one carbonate compound and component (C) are used synonymously and therefore have the same meaning.

[0026] The at least one aprotic polar solvent is also referred to as component (D). The terms at least one aprotic polar solvent and component (D) in the present invention are used synonymously and therefore have the same meaning.

[0027] The reaction mixture (R G ) in step i) is a product mixture (P G ) is provided to form a sulfonated polyarylene sulfone polymer (sP) contained in the reaction mixture (R G All components in relation to step i) relate to the mixture present prior to conversion according to step i), i.e. polycondensation.

[0028] The polycondensation is carried out by reacting the reaction mixture (R G ) is polycondensed with components (A) and (B) to produce a product mixture (P) containing a sulfonated polyarylene sulfone polymer (sP). G )

[0029] In step i), components (A) and (B) enter into a polycondensation reaction. Component (C) acts as a base to deprotonate the hydroxyl groups of component (B). Component (D) acts as a solvent.

[0030] The product mixture (P) obtained after polycondensation according to step i) G ) contains sulfonated polyarylene sulfone polymer (sP). G ) further comprises at least one inorganic halide compound, and at least one aprotic polar solvent (component (D)). The at least one inorganic halide compound is G During the conversion, component (C) reacts with component (B) to deprotonate component (B). The deprotonated component (B) then reacts with component (A) to form at least one inorganic halide compound. This process is known to those skilled in the art.

[0031] The reaction mixture (R GThe components of (a) are preferably reacted simultaneously. The individual components can be mixed in an upstream step and reacted subsequently. It is also possible for the individual components to be fed to a reactor, where they are mixed and then reacted.

[0032] In step i) of the process of the present invention, the reaction mixture (R G The individual components of (A) and (B) are preferably reacted simultaneously. The reaction is preferably carried out in one step. This means that the deprotonation of component (B) and also the condensation reaction between components (A) and (B) are preferably carried out in a single reaction step without isolation of intermediate products, e.g. the deprotonated species of component (B).

[0033] The reaction mixture (R G It is further preferred that the reaction mixture (R) does not contain toluene or monochlorobenzene. G It is particularly preferred that the product mixture (P) does not contain any substances that form azeotropes with water. G ) applies.

[0034] The ratio of components (A) and (B) in step i) is essentially derived from the stoichiometric ratios of the polycondensation reaction proceeding with the theoretical removal of hydrogen halide, preferably hydrogen chloride, and is established in a known manner by a person skilled in the art.

[0035] Preferably, in step i), the ratio of halogen end groups derived from component (A) to phenol end groups derived from component (B) is adjusted by establishing a controlled excess of component (A) relative to component (B) as starting compound.

[0036] More preferably, in step i), the molar ratio of component (A) to component (B) is between 0.95 and 1.08, in particular between 0.98 and 1.06, most preferably between 0.985 and 1.05.

[0037] Preferably, the conversion in the polycondensation reaction in step i) is at least 0.9.

[0038] The polycondensation reaction in step i) is generally carried out at a temperature in the range of 80 to 250° C., preferably in the range of 100 to 220° C. The upper temperature limit is preferably determined by the boiling point of the at least one aprotic polar solvent (component (D)) at standard pressure (1013.25 mbar). The reaction is generally carried out at standard pressure. The reaction is preferably carried out over a time interval in the range of 0.5 to 14 hours, in particular 1 to 12 hours.

[0039] In a preferred embodiment in step i), The reaction mixture (R G ) relative to the total molar amount of the aromatic dihalogen sulfone component (component (A)) in X 1 % by mole of at least one sulfonated aromatic dihalogen sulfone (component (A1)), and X 2 % by mole of at least one non-sulfonated aromatic dihalogen sulfone (component (A2)) where X 1 is in the range of 20 to 70, and X 2 is in the range of 30 to 80, X moles of an aromatic dihalogen sulfone component (component (A)), Y moles of at least one aromatic dihydroxy compound (component (B)); Z moles of at least one carbonate compound (component (C)) Including, The ratio of X to Y is in the range of 0.95 to 1.08; and Z is in the range of P to Q, P has the formula: P = Y × (1.05 + X 1 / 100×1.05) and Q is calculated by the following formula: Q = Y × (1.05 + X 1 / 100×1.4) It is calculated by The reaction mixture (R G ) is converted.

[0040] In a preferred embodiment, the sulfonated polyarylene sulfone polymer (sP) obtained in step i) is G ) is not separated from the

[0041] In one embodiment, no further process steps are carried out between steps i) and ii). In another embodiment, at least one further component (FC) is added to the product mixture (P) before or during step ii). G In a further preferred embodiment, the product mixture (P G The sulfonated polyarylene sulfone polymer (sP) in step ii) remains in dissolved form before step ii) is carried out.

[0042] Stage ii) In step ii), the inorganic halide compounds formed in step i) during the polycondensation reaction are reacted with the product mixture (P G ) to obtain a solution (S) containing the sulfonated polyarylene sulfone polymer (sP) and component (D).

[0043] Inorganic halide compounds may be removed by means routinely known in the art, such as filtration, centrifugation, decantation, and the like.

[0044] Thus, the present invention relates to a process comprising the steps of: ii) The product mixture (P) obtained in step i) G ) by filtering, centrifuging and / or decanting to obtain a solution (S). Also provided is a method comprising:

[0045] In a preferred embodiment, the solution (S) obtained in step ii) does not contain solid inorganic halide compounds. In a further preferred embodiment, the solution (S) obtained in step ii) contains less than 3% by weight, more preferably less than 1.5% by weight, and particularly preferably less than 0.5% by weight of inorganic halide components relative to the total weight of the solution (S) obtained in step ii).

[0046] In a more preferred embodiment, the solution (S) obtained in step ii) is free of solid inorganic compounds.

[0047] In a further preferred embodiment, the solution (S) obtained in step ii) comprises less than 0.4% by weight, more preferably less than 0.3% by weight and particularly preferably less than 0.2% by weight of inorganic components relative to the total weight of the solution (S) obtained in step ii).

[0048] In a preferred embodiment, the sulfonated polyarylene sulfone polymer (sP) in step ii) is not separated from the solution (S).

[0049] In one embodiment, no further method steps are carried out between step ii) and step iii).In a preferred embodiment, prior to step ii), at least one further component (FC) is added to the solution (S).

[0050] In a further preferred embodiment, the sulfonated polyarylene sulfone polymer (sP) in solution (S) in step ii) remains in dissolved form before step iii) is carried out.

[0051] In a particularly preferred embodiment, the sulfonated polyarylene sulfone polymer (sP) in the process of the invention remains dissolved until step iii) is carried out.

[0052] In a further particularly preferred embodiment, the sulfonated polyarylenesulfone polymer (sP) is not separated before step iii) is carried out. In other words, the method of the present invention preferably comprises only one separation step (step iii)) of the sulfonated polyarylenesulfone polymer (sP), in which the membrane (M) is formed.

[0053] Stage iii) In step iii), the at least one aprotic polar solvent is separated from the solution (S) to obtain the membrane (M). In a preferred embodiment, the solution (S) is degassed before step iii) is performed.

[0054] The separation of the at least one aprotic polar solvent from the solution (S) in step iii) can be carried out by any method known to the skilled artisan suitable for separating solvents from polymers.

[0055] Preferably, the separation of the at least one aprotic polar solvent from the solution (S) in step iii) is carried out via a phase inversion method.

[0056] The phase inversion method in the context of the present invention refers to a method in which dissolved sulfonated polyarylenesulfone polymer (sP) is transferred to a solid phase. The phase inversion method can therefore also be referred to as a precipitation method. According to step iii), the transfer is preferably carried out by separating at least one aprotic polar solvent from the sulfonated polyarylenesulfone polymer (sP). Suitable phase inversion methods are known to those skilled in the art.

[0057] The phase inversion method can be carried out, for example, by cooling the solution (S). During this cooling, the sulfonated polyarylene sulfone polymer (sP) contained in this solution (S) precipitates. Another possibility for carrying out the phase inversion method is to contact the solution (S) with a protic polar liquid that is a non-solvent for the sulfonated polyarylene sulfone polymer (sP). In that case, the sulfonated polyarylene sulfone polymer (sP) also precipitates. Suitable protic polar solvents that are non-solvents for the sulfonated polyarylene sulfone polymer (sP) are, for example, the protic polar solvents in the liquid state described below. Another phase inversion method that is preferred in the context of the present invention is phase inversion by immersing the solution (S) in at least one protic polar solvent.

[0058] Thus, in one embodiment, in step iii), at least one aprotic polar solvent contained in the solution (S) is separated from the sulfonated polyarylene sulfone polymer (sP) contained in the solution (S) by immersing the solution (S) in at least one protic polar solvent.

[0059] This means that in step iii) the membrane (M) is formed by immersing the solution (S) in at least one protic polar solvent.

[0060] Suitable at least one protic polar solvent is known to those skilled in the art. Preferred at least one protic polar solvent is water, methanol, ethanol, n-propanol, isopropanol, glycerol, ethylene glycol and mixtures thereof.

[0061] Thus, in one preferred embodiment, step iii) comprises the steps of: iii-1) casting the solution (S) prepared in step ii) to obtain a film of the solution (S); iii-2) Separating at least one aprotic polar solvent from the film of solution (S) obtained in step iii-1) to obtain a membrane (M) in the form of a film. Includes.

[0062] The separation in step iii-2) can be carried out as described above. Preferably, the separation in step iii-2) is carried out by evaporating at least one aprotic polar solvent from the film of solution (S).

[0063] Thus, in a particularly preferred embodiment, step iii) comprises the steps of: iii-1) casting the solution (S) prepared in step ii) to obtain a film of the solution (S); iii-2) evaporating at least one aprotic polar solvent from the film of solution (S) obtained in step iii-1) to obtain a membrane (M) in the form of a film. Includes.

[0064] This means that the membrane (M) is formed by evaporating at least one aprotic polar solvent from a film of the solution (S).

[0065] In step iii-1), the solution (S) can be cast by any method known to those skilled in the art. Usually, the solution (S) is cast using a casting knife, a cast bar, a Mayer bar, a slot die or a reverse roll, preferably heated to a temperature in the range of 20 to 150°C, preferably in the range of 40 to 100°C, more preferably in the range of 60 to 85°C.

[0066] In step iii-1), the solution (S) is typically cast onto a substrate (support material) that does not react with the sulfonated polyarylenesulfone polymer (sP) and / or at least one solvent contained in the solution (S).

[0067] Suitable substrates (support materials) are, for example, steel belts, drying cylinders or polymer films. The substrate (support material) is generally not part of the finished membrane (M) but is only used for processing.

[0068] It is also possible to cast the solution (S) onto a porous support layer that becomes part of the membrane (M).

[0069] After step iii), the membrane may be further processed, for example the membrane may be coated with a stabilizer or a catalyst.

[0070] Suitable stabilizers are, for example, cerium dioxide, cerium-containing complexes, or titanium dioxide.

[0071] Suitable catalysts are, for example, selected from the group consisting of platinum, iridium, ruthenium or palladium in elemental form or in the form of their oxides, mixtures or alloys, either as powder or deposited on a catalyst support, such as SnO2, carbon or TiO2.

[0072] To produce a catalyst coated membrane (CCM), the catalyst can be dispersed in a medium including water, alcohol and other solvents along with a binder. The binder can be a proton conducting polymer, such as Nafion, sulfonated polyarylether, sulfonated polystyrene copolymer. This dispersion is then coated onto the membrane by common coating techniques (slot die coating, doctor blade coating, spray coating).

[0073] Component (A) Component (A), also referred to as the aromatic dihalogen sulfone component, comprises at least one sulfonated aromatic dihalogen sulfone and at least one non-sulfonated aromatic dihalogen sulfone.

[0074] The at least one sulfonated aromatic dihalogen sulfone is also referred to as component (A1). The terms at least one sulfonated aromatic dihalogen sulfone and component (A1) in the present invention are used synonymously and therefore have the same meaning.

[0075] The at least one non-sulfonated aromatic dihalogen sulfone is also referred to as component (A2). The terms at least one non-sulfonated aromatic dihalogen sulfone and component (A2) in the present invention are used synonymously and therefore have the same meaning.

[0076] Here, "at least one sulfonated aromatic dihalogen sulfone" means exactly one sulfonated aromatic dihalogen sulfone, and also a mixture of two or more sulfonated aromatic dihalogen sulfones. Preferably, exactly one sulfonated aromatic dihalogen sulfone is used.

[0077] Here, "at least one non-sulfonated aromatic dihalogen sulfone" means exactly one non-sulfonated aromatic dihalogen sulfone, and also a mixture of two or more non-sulfonated aromatic dihalogen sulfones. Preferably, exactly one non-sulfonated aromatic dihalogen sulfone is used.

[0078] In the above-mentioned preferred embodiment, "X" is preferably the reaction mixture (R G ) in step i), where "X" preferably means the molar amount of component (A) in the reaction mixture (R G In other words, "X" preferably refers to the total molar amount of aromatic dihalogen sulfone component (component (A)) contained in component (A), preferably the total molar amount of aromatic dihalogen sulfone component (component (A)) contained in the reaction mixture (R G The molar amount of component (A1) and component (A2) contained in the reaction mixture (R G ) in which "X 1 " means the molar amount in mole percent of component (A1), and where "X 2 " means the molar amount in mole % of component (A2).

[0079] X 1 are the reaction mixtures (R G(A)) in the copolymer (A), the molar amount of the aromatic dihalogen sulfone component (component (A)) may be in the range of 20 to 70 mol %, preferably in the range of 27.5 to 65 mol %, more preferably in the range of 30 to 60 mol %, and most preferably in the range of 32.5 to 57.5 mol %.

[0080] X 2 are the reaction mixtures (R G The molar amount of the aromatic dihalogen sulfone component (component (A)) in the copolymer (A) may be in the range of 30 to 80 mol %, preferably in the range of 35 to 72.5 mol %, more preferably in the range of 40 to 70 mol %, and most preferably in the range of 42.5 to 67.5 mol %, based on the total molar amount of the aromatic dihalogen sulfone component (component (A)) in the copolymer (A).

[0081] X 1 and X 2 The amounts generally total 100 mole %.

[0082] Ingredient (A1) Component (A1) is also referred to as sulfonated aromatic dihalogen sulfone, and preferably has at least one -SO3X 3 Contains a group.

[0083] Component (A1) preferably contains at least one -SO3X 3 In this case, "at least one -SO3X 3 The "group" is a group in which the component (A1) is exactly one -SO3X 3 Group, and two or more -SO3X 3 It means that the component (A1) may also contain two -SO3X groups. 3 Contains a group.

[0084] General formula -SO3X 3 Also includes sulfonic acid functional groups and derivatives of sulfonic acid functional groups, such as sulfonates. 3 In the group, X 3 may be hydrogen and / or one cation equivalent.

[0085] In the context of the present invention, "one cation equivalent" means one cation with a single positive charge, or one charge equivalent of a cation with two or more positive charges, such as Li, Na, K, Mg, Ca, NH4, preferably Na, K. Na or K is particularly preferred.

[0086] Component (A1) is preferably selected from the group consisting of 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid, and 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid, and derivatives thereof.

[0087] The term "sulfonic acid" and "-SO3X 3 The terms "sulfonic acid" and "sulfonic acid group" are used interchangeably and have the same meaning. Thus, the term "sulfonic acid" in 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid and 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid is understood to mean "-SO3X 3 where X means "group" 3 is hydrogen or a cation equivalent.

[0088] In one embodiment, component (A1) preferably has the cation equivalent -SO3X 3 Particularly preferably, component (A1) is selected from the group consisting of 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid disodium salt, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt, 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid, 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid disodium salt, and 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt.

[0089] Another subject of the present invention is therefore a process, wherein component (A1) comprises at least one compound selected from the group consisting of 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid disodium salt, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt, 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid, 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid disodium salt and 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt.

[0090] In one embodiment, component (A1) is a reaction mixture (R G 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid disodium salt, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt, 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid, 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid disodium salt, and 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt, 3 The compound includes at least one aromatic dihalogen sulfone component that includes a group.

[0091] In a further particularly preferred embodiment, component (A1) is at least one -SOX selected from the group consisting of 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid disodium salt, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt, 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid, 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid disodium salt, and 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt. 3 The aromatic dihalogen sulfone comprises at least one aromatic dihalogen sulfone containing a group.

[0092] In those embodiments, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt and 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid disodium salt are particularly preferred for use as component (A1).

[0093] In a further particularly preferred embodiment, component (A1) consists of 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt or 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid disodium salt.

[0094] Ingredients (A2) Component (A2) is also referred to as a non-sulfonated aromatic dihalogen sulfone component and is preferably -SO3X 3 Does not contain any group.

[0095] Preferably, component (A2) is present in the reaction mixture (R G), based on the total weight of component (A2) in the composition, 80% by weight or more, preferably 90% by weight or more, and more preferably 98% by weight or more of at least one aromatic dihalogen sulfone selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone, where the weight percentage with respect to component (A2) further relates to the total sum of the 4,4'-dichlorodiphenyl sulfone and the 4,4'-difluorodiphenyl sulfone used.

[0096] Another object of the present invention is therefore to provide a process for the preparation of a reaction mixture (R G The component (A2) in the polymerization initiator (A1) contains at least one aromatic dihalogen sulfone selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone in an amount of 80 mass% or more based on the total mass of the component (A2) in the polymerization initiator (A1).

[0097] In a further particularly preferred embodiment, component (A2) consists of at least one aromatic dihalogen sulfone selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone.

[0098] In those embodiments, 4,4'-dichlorodiphenyl sulfone is particularly preferred for use as component (A2).

[0099] In a further particularly preferred embodiment, component (A2) consists of 4,4'-dichlorodiphenylsulfone.

[0100] Preferably, component (A2) is selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone.

[0101] Ingredient (B) Component (B), also known as an aromatic dihydroxy compound, generally contains two hydroxy groups.

[0102] Here, "at least one aromatic dihydroxy compound" means exactly one aromatic dihydroxy compound, and also a mixture of two or more aromatic dihydroxy compounds. Preferably, exactly one aromatic dihydroxy compound is used.

[0103] In the above-mentioned preferred embodiment, "Y" is preferably the reaction mixture (R G ) in step i), where "Y" preferably means the molar amount of component (B) in the reaction mixture (R G (B)) means the total molar amount of the aromatic dihydroxy compound (component (B)) in the mixture.

[0104] Preferably, component (B) is selected from the group consisting of 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone, bisphenol A (2,2-bis(4-hydroxyphenyl)propane), 4,4'-dihydroxybenzophenone, and hydroquinone. Of the above-mentioned aromatic dihydroxy components, 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone, and bisphenol A are preferred, while 4,4'-dihydroxybiphenyl is particularly preferred.

[0105] Thus, the present invention also provides a method, wherein component (B) is selected from the group consisting of 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone, bisphenol A, 4,4'-dihydroxybenzophenone, and hydroquinone.

[0106] Preferably, component (B) is present in the reaction mixture (R G ) contains 80% by mass or more, preferably 90% by mass or more, and more preferably 98% by mass or more of 4,4'-dihydroxybiphenyl, based on the total mass of component (B) in the composition (B).

[0107] A further object of the present invention is therefore to provide a process for the preparation of a reaction mixture (R G In the method, the component (B) in the composition (1) contains 80 mass % or more of 4,4'-dihydroxybiphenyl based on the total mass of the component (B) in the composition (1).

[0108] Here, the mass percentages relating to component (B) further relate to the total sum of 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone, bisphenol A (2,2-bis-(4-hydroxyphenyl)propane), 4,4'-dihydroxybenzophenone and hydroquinone used.

[0109] In a further particularly preferred embodiment, component (B) comprises at least one aromatic dihydroxy component selected from the group consisting of 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone, bisphenol A (2,2-bis(4-hydroxyphenyl)propane), 4,4'-dihydroxybenzophenone, and hydroquinone.

[0110] Within those embodiments, 4,4'-dihydroxybiphenyl, bisphenol A, and 4,4'-dihydroxydiphenyl sulfone are particularly preferred for use as component (B), while 4,4'-dihydroxybiphenyl is most preferred.

[0111] Ingredients (C) The reaction mixture (R G ) comprises at least one carbonate compound as component (C). In this case, the term "at least one carbonate compound" is understood to mean exactly one carbonate compound, and also a mixture of two or more carbonate compounds. The at least one carbonate compound is preferably at least one metal carbonate. The metal carbonate is preferably anhydrous. In this case, the terms "at least one carbonate compound" and "component (C)" are used synonymously and therefore have the same meaning.

[0112] Alkali metal carbonates and / or alkaline earth metal carbonates are preferred as metal carbonates. At least one metal carbonate selected from the group consisting of sodium carbonate, potassium carbonate and calcium carbonate is particularly preferred as metal carbonate. Potassium carbonate is most preferred.

[0113] For example, component (C) may be added to the reaction mixture (R G ), more preferably 50% by weight or more, more preferably 70% by weight or more, and most preferably 90% by weight or more of potassium carbonate, based on the total weight of the at least one carbonate component in the composition.

[0114] Another object of the present invention is therefore to provide a process for the preparation of a reaction mixture (R G ) contains 50 mass% or more of potassium carbonate based on the total mass of component (C) in the composition (C).

[0115] In a preferred embodiment, component (C) consists of potassium carbonate. Potassium carbonate having a volume weighted mean particle size of less than 200 μm, more preferably less than 100 μm, even more preferably less than 70 μm, and most preferably less than 50 μm is preferred as potassium carbonate. The volume weighted mean particle size of potassium carbonate is determined in a suspension of potassium carbonate in a mixture of chlorobenzene / sulfolane (60 / 40 by mass) using a particle size analyzer.

[0116] In the above preferred embodiment, "Z" is preferably the reaction mixture (R G ) in which "Z" preferably refers to the molar amount of component (C) in the reaction mixture (R G (C)) in the aqueous solution.

[0117] Z is in the range of P to Q.

[0118] "P" is of the formula: P = Y × (1.05 + X 1 / 100×1.05) It is calculated according to:

[0119] "Q" is the formula: Q = Y × (1.05 + X 1 / 100×1.4) It is calculated according to:

[0120] In this formula, Y is the reaction mixture (RG ) is the molar amount of component (B) in 1 The reaction mixture (R G ) is the mole percentage of component (A1).

[0121] Ingredients (D) The reaction mixture (R G ) preferably comprises at least one aprotic polar solvent as component (D). According to the present invention, "at least one aprotic polar solvent" is understood to mean exactly one aprotic polar solvent, and also a mixture of two or more aprotic polar solvents. In this case, the terms "at least one aprotic polar solvent" and "component (D)" are used synonymously and therefore have the same meaning.

[0122] Suitable aprotic polar solvents are, for example, selected from the group consisting of anisole, dimethylformamide, dimethylsulfoxide, sulfolane, N-methylpyrrolidone, N-ethylpyrrolidone, and N-dimethylacetamide.

[0123] Preferably, component (D) is selected from the group consisting of N-methylpyrrolidone, N-dimethylacetamide, dimethylsulfoxide and dimethylformamide. N-methylpyrrolidone is particularly preferred as component (D).

[0124] Component (D) is added to the reaction mixture (R G It is preferred that the component (D) in the composition contains at least one solvent selected from the group consisting of N-methylpyrrolidone, N-dimethylacetamide, dimethylsulfoxide and dimethylformamide in an amount of 50% by mass or more, preferably 70% by mass or more, and more preferably 90% by mass or more, based on the total mass of the component (D). N-methylpyrrolidone is particularly preferred as the component (D).

[0125] Another object of the present invention is therefore to provide a method for preparing a reaction mixture (R GThe method further comprises the step of: (A) adding at least one solvent selected from the group consisting of N-methylpyrrolidone, N-dimethylacetamide, dimethylsulfoxide, and dimethylformamide in an amount of 50 mass% or more based on the total mass of component (D) in the composition (A).

[0126] In a preferred embodiment, component (D) consists of N-methylpyrrolidone, also called NMP or N-methyl-2-pyrrolidone.

[0127] Further ingredients (FC) In a preferred embodiment, the membrane (M) comprises at least one further component as component (FC). According to the present invention, "at least one further component" is understood to mean exactly one further component, and also a mixture of two or more further components. In this case, the terms "at least one further component" and "component (C)" are used synonymously and therefore have the same meaning.

[0128] In a preferred embodiment, component (FC) is added in the process of the invention before or during step iii), preferably before step iii) is performed. In another preferred embodiment, component (FC) is added to the solution (S) obtained in step ii) before step iii) is performed.

[0129] Component (FC) is preferably at least one component selected from the group of stabilizers and hydrophilic polymers.

[0130] Component (D), a component that is soluble in at least one aprotic organic solvent, is preferred as component (FC).

[0131] Suitable stabilizers are, for example, heat stabilizers, antioxidant stabilizers, or organic radical scavengers.

[0132] As suitable stabilizers, sterically hindered phenols, phosphites or quinones can be used.A suitable radical scavenger is, for example, (4-hydroxy-2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO).

[0133] Further details about suitable additives can be found in "Polymer Stabilisation" by P. Gijsman, Handbook of Environmental Degradation of materials, 3rd Edition, William Andrew, 2018.

[0134] Suitable hydrophilic polymers are, for example, polyvinylpyrrolidone (PVP), polyethylene oxide, polyethylene oxide-polypropylene oxide copolymers.

[0135] A membrane (M) containing a sulfonated polyarylene sulfone polymer (sP). Another subject of the invention is a membrane (M) comprising a sulfonated polyarylenesulfone polymer (sP) obtainable by the process of the invention.

[0136] The sulfonated polyarylenesulfone polymer (sP) obtained in step i) of the inventive process for producing a membrane (M) preferably has the general formula I: [ka] In the formula, t and q are each independently 0, 1, 2 or 3; Q 1 , T and Y 1 are each independently a chemical bond or -O-, -S-, -SO2-, -S(=O)-, -C(=O)-, -N=N- and -CR a R b - selected from R a and R b are each independently a hydrogen atom or a C1-C 12 -Alkyl, C1-C12 -Alkoxy or C6-C 18 -aryl group, and at least one of Q, T and Y is -SO2-; Ar and Ar 1 are each independently C6 to C 18 -aryl, 18 -Aryl is unsubstituted or C1-C 12 -Alkyl, C1-C 12 -Alkoxy, C6~C 18 -substituted with at least one substituent selected from aryl, halogen and -SO3X; p, m, n and k are each independently 0, 1, 2, 3 or 4, with the proviso that the total of p, m, n and k is equal to or greater than 1; and X 3 is hydrogen or one cation equivalent.

[0137] Another subject of the present invention is therefore a membrane (M) comprising a sulfonated polyarylenesulfone polymer (sP), which comprises recurring units of general formula (I) as defined above.

[0138] In a preferred embodiment, the sulfonated polyarylenesulfone polymer (sP) contained in the membrane (M) contains at least 80 mol % of repeating units of general formula (I) relative to the total molar amount of the sulfonated polyarylenesulfone polymer (sP) contained in the membrane (M).

[0139] Under the above preconditions, Q 1 , T or Y 1 is a chemical bond, this means that the left adjacent group and the right adjacent group are directly attached to each other by a chemical bond.

[0140] R a and R b are each independently hydrogen or C1-C 12 -alkyl.

[0141] Preferred C1-C 12 -Alkyl groups include linear and branched, saturated alkyl groups of 1 to 12 carbon atoms. The following moieties are particularly suitable: C1-C6-alkyl, such as methyl, ethyl, n-propyl, i-propyl, n-butyl, sec-butyl, 2- or 3-methylpentyl, or longer chain moieties, such as unbranched heptyl, octyl, nonyl, decyl, undecyl, lauryl, and their branched analogues.

[0142] Used C1~C 12 The alkyl moiety in the alkoxy group comprises an alkyl group as defined above having 1 to 12 carbon atoms. Preferably used cycloalkyl moieties are in particular C3-C 12 -Cycloalkyl moieties include, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclopropylmethyl, cyclopropylethyl, cyclopropylpropyl, cyclobutylmethyl, cyclobutylethyl, cyclopentylethyl, -propyl, -butyl, -pentyl, -hexyl, -cyclohexylmethyl, -dimethyl, -trimethyl.

[0143] Ar and Ar 1 are each independently C6~C 18 Starting from the starting materials described below, Ar is preferably derived from an aromatic substance that is highly susceptible to electrophilic attack and is preferably selected from the group consisting of sulfonated or non-sulfonated hydroquinone, resorcinol, dihydroxynaphthalene, in particular 2,7-dihydroxynaphthalene. 1 is preferably unsubstituted C6 or C 12 -arylene group.

[0144] Ar and Ar in preferred embodiments of formula (I) 1 are each preferably independently selected from sulfonated or non-sulfonated 1,4-phenylene, 1,3-phenylene, naphthylene, in particular 2,7-dihydroxynaphthalene and 4,4'-bisphenylene.

[0145] The following structural units (Ia)-(Io): [ka]

[0146] [ka] Preferred is a membrane (M) containing a sulfonated polyarylene sulfone polymer (sP) having one or more of the following formulas: l, k, m, n, o, and p are each independently 0, 1, 2, 3, or 4, with the proviso that the sum of l, k, m, n, o, and p is ≧1; and X 3 is hydrogen or one cation equivalent.

[0147] In the context of the present invention, "one cation equivalent" means one cation with a single positive charge, or one charge equivalent of a cation with two or more positive charges, e.g. Li, Na, K, Mg, Ca, NH4, preferably Na, K.

[0148] In addition to the preferred building blocks (Ia) to (Io), also preferred are structural units in which one or more sulfonated or non-sulfonated 1,4-dihydroxyphenyl units are replaced by resorcinol or dihydroxynaphthalene.

[0149] Copolymers consisting of a combination of various structural units, or sulfonated and non-sulfonated structural units, are also useful.

[0150] The structural units (Ia), (Ib), (Ig) and (Ik) or copolymers thereof are particularly preferably used as repeating units of the general formula (I).

[0151] In one particularly preferred embodiment, Ar is 1,4-phenylene, t is 1, T is a chemical bond, and Y 1is -SO2-, q is 0, p is 0, m is 0, n is 1, and k is 1. A sulfonated polyphenylsulfone composed of repeating units of this listed structure is represented as sPPSU.

[0152] In a particularly preferred embodiment, Ar is 1,4-phenylene, t is 0, Y is -SO2-, q is 0, n is 0, and k is 0. Polyarylene sulfones composed of repeating units of the above listed structures are referred to as sulfonated polyether ether sulfones (sPEES).

[0153] In one advantageous embodiment, the membrane (M) has the formula (1) [ka] and non-sulfonated repeating units of formula (2) [ka] The sulfonated polyarylene sulfone polymer (sP) comprises sulfonated repeating units of the formula:

[0154] In particular, the sulfonated polyarylenesulfone polymer (sP) contained in the membrane (M) consists exclusively of non-sulfonated repeat units of formula (1) and sulfonated repeat units of formula (2).

[0155] In a very advantageous embodiment, the sulfonated polyarylene sulfone polymer (sP) contained in the membrane has the formula (1a) [ka] and non-sulfonated repeat units of formula (2a) [ka] The sulfonated repeat unit comprises:

[0156] In particular, the sulfonated polyarylenesulfone polymer (sP) contained in the membrane (M) consists exclusively of non-sulfonated repeat units of formula (1a) and sulfonated repeat units of formula (2a).

[0157] The sulfonated polyarylenesulfone polymer (sP) contained in the membrane (M) according to the invention preferably has a viscosity number of 20 ml / g to 250 ml / g, preferably 50 ml / g to 200 ml / g. This viscosity number is quantified in accordance with DIN EN ISO 1628-1 in a 1% solution in N-methylpyrrolidone (NMP) at 25° C. Measurements can also be carried out at lower polymer concentrations, for example 0.5%.

[0158] The mass average molecular weight (M W The mass average molecular weight (M) is generally in the range of 10,000 to 250,000 g / mol, preferably in the range of 15,000 to 200,000 g / mol, and more preferably in the range of 18,000 to 150,000 g / mol. W ) was measured using gel permeation chromatography (GPC). In the measurements, dimethylacetamide (DMAc) was used as the solvent and narrow distribution polymethylmethacrylate was used as the standard.

[0159] In a preferred embodiment, the membrane (M) obtained by the method of the present invention has a good balance between low swelling and high conductivity.

[0160] Apparatus containing a membrane (M) Another subject of the invention is a device comprising a membrane (M) obtainable by the method of the invention, said device being preferably a fuel cell or an electrolysis cell.

[0161] Another subject of the invention is therefore a fuel cell comprising a membrane (M) obtainable by the method of the invention. Furthermore, another subject of the invention is an electrolysis cell comprising a membrane (M) obtainable by the method of the invention. Furthermore, another subject of the invention is the use of a membrane (M) obtainable by the method of the invention in an electrolysis cell or in a fuel cell.

[0162] In order to use the membrane (M) obtained by the method of the present invention, in a preferred embodiment, the membrane (M) is activated. Activation can be carried out by contacting the membrane (M) with an aqueous acid solution, for example an aqueous inorganic acid solution. Preferably, an aqueous solution of sulfuric acid (H2SO4) is used for activation. The concentration of the aqueous acid solution is preferably in the range of 0.1 to 4.0 M. After contacting the membrane (M) with the aqueous acid solution, for example an aqueous sulfuric acid solution, the membrane can be contacted with water, preferably deionized water. After activation, the membrane (M) is typically contacted with H + It is obtained in the form.

[0163] In other words, after activation, the sulfonated polyarylene sulfone polymer (sP) contained in the membrane (M) is -SO3X contained in the sulfonated polyarylene sulfone polymer (sP). 3 It contains at least 70 mol %, more preferably at least 80 mol %, and particularly preferably at least 90 mol % -SO3H groups, based on the total molar amount of groups. [Brief description of the drawings]

[0164] [Figure 1] FIG. 1 is a diagram showing an example of the present invention and a comparative example. EXAMPLES

[0165] The present invention will be further illustrated by the following examples, but is not limited thereto.

[0166] Ingredients used: DCDPS 4,4'-dichlorodiphenyl sulfone sDCDPS 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid disodium salt BP 4,4'-dihydroxybiphenyl K2CO3 Potassium Carbonate, Anhydrous, Average Particle Size 32.6μm NMP N-Methylpyrrolidone, anhydrous.

[0167] The viscosity number VN of the sulfonated polyarylene sulfone polymers (sP) was determined in 0.5% by weight NMP solution according to DIN ISO 1628-1.

[0168] The incorporation rate of sDCDPS is 1 The polymer content of the polymer solution after filtration was also determined by H-NMR in CDCl3. 1 Quantification was performed in CDCl3 by 1 H-NMR.

[0169] The isolation of the sulfonated polyarylenesulfone polymer (sP) is carried out by dropping a solution of the sulfonated polyarylenesulfone polymer (sP) in NMP into isopropanol at room temperature, unless otherwise indicated. The dropping height is 0.5 m. The throughput is about 2.5 l per hour. The resulting beads are then extracted with water at 85° C. for 20 hours (water throughput 160 l / h). The beads are then cooled to the glass transition temperature T g The beads are dried at a lower temperature to a residual moisture content of less than 1.0% by weight. In some cases, the beads are washed at least once with isopropanol and then dried at a lower temperature to a residual moisture content of less than 1.0% by weight. g The mixture is dried at a temperature below 100° C., preferably under vacuum, to a residual isopropanol content of less than 1% by weight. In some cases, a powder is obtained by precipitation, which is then filtered off and washed at least once with isopropanol. The powder is then extracted with water or isopropanol, and finally the product T g The mixture is then dried at a temperature below 50° C., preferably under vacuum, to a residual moisture or isopropanol content of less than 1% by weight.

[0170] Filtration of the product mixture was performed in a heated metal pressure filter using a filter with a pore size of 5 μm and 3 bar N2 pressure. The filter was heated to 60° C. to reduce the viscosity of the reaction mixture.

[0171] The yield of polymer after precipitation was determined gravimetrically.

[0172] Synthesis example 1: In a 4 liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark trap, 288.599 g (1.005 mol) of DCDPS, 257.906 g (0.525 mol) of sDCDPS, 279.315 g (1.50 mol) of BP and 308.209 g (2.23 mol) of potassium carbonate with a volume average particle size of 32.6 μm were suspended in 938 ml of NMP under a nitrogen atmosphere. The mixture was heated to 190 ° C within 1 h. In the following, the reaction time should be understood as the time during which the reaction mixture was held at 190 ° C. The water formed in the reaction was continuously removed by distillation to replenish the loss of NMP.

[0173] After 9 hours of reaction time, the reaction was stopped by adding 1750 ml of NMP and cooled to room temperature (within 1 hour). The potassium chloride formed in the reaction was removed by filtration. The resulting polymer solution was then divided into two equal parts. One part was precipitated in isopropanol, the resulting polymer beads were separated and then extracted with hot water (85° C.) for 20 hours. The beads were then dried under reduced pressure (<100 mbar) at 120° C. for 24 hours. The other part of the solution was used for the preparation of the membrane. The polymer content of this solution was 18.1% by weight.

[0174] Synthesis example 2: In a 4 liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark trap, 267.059 g (0.93 mol) of DCDPS, 294.750 g (0.60 mol) of sDCDPS, 279.315 g (1.50 mol) of BP and 317.883 g (2.30 mol) of potassium carbonate with a volume average particle size of 32.6 μm were suspended in 938 ml of NMP under a nitrogen atmosphere. The mixture was heated to 190 ° C within 1 h. In the following, the reaction time should be understood as the time during which the reaction mixture was held at 190 ° C. The water formed in the reaction was continuously removed by distillation to replenish the loss of NMP.

[0175] After 9 hours of reaction time, the reaction was stopped by adding 2312 ml of NMP and cooled to room temperature (within 1 hour). The potassium chloride formed in the reaction was removed by filtration. The resulting polymer solution was divided into equal mass portions. One portion was then precipitated in isopropanol, the resulting polymer beads were separated and then extracted with hot water (85° C.) for 20 hours. The beads were then dried under reduced pressure (<100 mbar) at 120° C. for 24 hours. The other portion of the solution was used for the preparation of the membrane. The polymer content of this solution was 18.1% by mass.

[0176] [Table 1]

[0177] To produce the membrane, solutions of the precipitated sulfonated polyarylenesulfone polymer (sP) in NMP from Examples 1 and 2 were prepared using a polymer content of 17.5% by weight. The solutions made from the precipitated sulfonated polyarylenesulfone polymer (sP) obtained in Examples 1 and 2 are referred to below as 1P and 2P.

[0178] The unprecipitated solutions obtained in Examples 1 and 2 were diluted with NMP to a polymer content of 17.5% by weight and are referred to below as 1S and 2S.

[0179] Membrane manufacturing method 1 Membranes from solutions 1P, 2P, 1S and 2S were produced by casting the solutions on a glass plate with a doctor blade at a speed of 5 mm / s and a temperature of 60° C. The glass plate was transferred into a vacuum oven and the temperature was gradually increased to 100° C. and kept there for 12 hours. After cooling to room temperature, the plate was placed in a water bath and the membrane was peeled off from the glass plate. The wet membrane was then clamped and dried in vacuum at 120° C. for 12 hours. The membrane obtained from solution 1P is hereinafter referred to as 1PM1. The membrane obtained from solution 2P is hereinafter referred to as 2PM1. The membrane obtained from solution 1S is hereinafter referred to as 1SM1. The membrane obtained from solution 2S is hereinafter referred to as 2SM1.

[0180] Membrane manufacturing method 2 Membranes from solutions 1P, 2P, 1S and 2S were also produced, where the casting was also carried out according to the following procedure: To produce monolayer films, an automatic film applicator and a universal applicator (from Zehntner) were used. The coating solutions 1P, 2P, 1S and 2S were applied to a PET substrate (Hostaphan®, Mitsubishi Polyester Film). The gap width of the doctor blade was selected so that the layer after drying at 70° C. had a thickness of 60 μm. The film was subsequently peeled off from the PET support for further processing. The membrane obtained from solution 1P is referred to below as 1PM2. The membrane obtained from solution 2P is referred to below as 2PM2. The membrane obtained from solution 1S is referred to below as 1SM2. The membrane obtained from solution 2S is referred to below as 2SM2.

[0181] The membranes prepared as described above were cut to the required size (5 x 5 cm). For activation, the membranes were immersed in 0.5 M H2SO4 at 80 °C for 2 h. Subsequently, the membranes were immersed in deionized water (MiliQ 18.2 MΩ) at 80 °C for another 2 h and finally stored at room temperature in a fresh batch of deionized water. The swelling in the xy direction of the membrane was determined by measuring the respective length before and after activation. The swelling in the z direction was determined by measuring the thickness of the membrane before and after activation using a micrometer. To determine the conductivity, two rectangular gold electrodes (0.25 cm 2 The membrane was sandwiched in a dedicated Teflon cell equipped with a pressure adjusting mechanism (PFA) and a pressure adjusting mechanism (PFA). A constant pressure was achieved by adjusting the torque of the four screws to 4 Nm.

[0182] [Table 2]

[0183] Membranes resulting from the direct use of sulfonated polyarylene sulfone polymer (sP) solutions exhibit improved conductivity along with reduced swelling.

[0184] Catalyst Coated Membrane (CCM) Manufacturing To fabricate the catalyst coated membrane (CCM), + The activated membrane 1SM1 (in the form of a 100 μm thick film) was dried at room temperature and sandwiched between two porous PE sheets (SP Bel-Art, Fritware porous polyethylene sheets, medium porosity, 0.125 inches thick) to avoid rolling up.

[0185] Catalyst coating of membrane 1SM1 was performed by spray coating catalyst ink (91.6 wt% HO, 3.4 wt% Nafion, 0.8 wt% catalyst, 4.2 wt% dispersant) onto both sides of membrane 1SM1 placed on a hot plate at 60 °C. After coating both sides (anode side 1 cm 2 2 mg of Ir black per cm, cathode side 1 cm 2The catalyst coated membrane 1SM1 was calendered at 130° C. The final CCM 1SM1 was then assembled into a single cell PEM test fixture and subjected to a polarization curve at 80° C.

[0186] The activated membrane 1PM1 was used to prepare other catalyst coated membranes, where the preparation was carried out as described above.

[0187] As a comparative example, prior art Nafion 117 coated with the same catalyst loading was measured.

[0188] With CCM 1SM1, behavior comparable to Nafion117 was achieved (Figure 1), while CMC 1PM1 showed much higher resistance.

Claims

1. A method for producing a membrane (M) containing a sulfonated polyarylene sulfone polymer (sP), comprising: i) an aromatic dihalogen sulfone component (component (A)) comprising at least one sulfonated aromatic dihalogen sulfone (component (A1)) and at least one non-sulfonated aromatic dihalogen sulfone (component (A2)); at least one aromatic dihydroxy compound (component (B)); at least one carbonate compound (component (C)), and At least one aprotic polar solvent (component (D)) A reaction mixture (R G ) to produce a product mixture (P) comprising a sulfonated polyarylene sulfone polymer (sP), at least one aprotic polar solvent, and at least one inorganic halide compound. G ) ii) adding said at least one inorganic halide to said product mixture (P G ) to obtain a solution (S) comprising a sulfonated polyarylene sulfone polymer (sP) and at least one aprotic polar solvent; iii) separating said at least one aprotic polar solvent from said solution (S) to obtain a membrane (M) containing a sulfonated polyarylene sulfone polymer (sP). wherein the sulfonated polyarylene sulfone polymer (sP) in the solution (S) in step ii) remains in dissolved form before step iii) is carried out.

2. 2. The method of claim 1, wherein component (A1) comprises at least one compound selected from the group consisting of 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid disodium salt, 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt, 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid, 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid disodium salt, and 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid dipotassium salt.

3. Component (A2) is a reaction mixture (R G 2. The method according to claim 1, wherein the component (A2) in the composition (A1) contains at least one aromatic dihalogen sulfone selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone in an amount of 80% by mass or more, based on the total mass of the component (A2) in the composition (A1).

4. Component (B) is a reaction mixture (R G The method according to claim 1, wherein the component (B) contains 80% by weight or more of 4,4'-dihydroxybiphenyl based on the total weight of the component (B) in the composition (B).

5. Component (C) is a reaction mixture (R G 2. The method of claim 1, wherein the component (C) comprises 50% by weight or more of potassium carbonate, based on the total weight of component (C) in the composition.

6. Component (D) is a reaction mixture (R G 2. The method according to claim 1, wherein the composition contains at least one solvent selected from the group consisting of N-methylpyrrolidone, N-dimethylacetamide, dimethyl sulfoxide, and dimethylformamide in an amount of 50% by mass or more, based on the total mass of component (D) in the composition.

7. Component (A) is a reaction mixture (R G The method according to claim 1, wherein the component (A) is present in an amount of 20 to 70 mol % of the component (A1) and 30 to 80 mol % of the component (A2), based on the total molar amount of the component (A) in the copolymer (A).

8. Step iii) is the following step iii-1) casting the solution (S) prepared in step ii) to obtain a film of the solution (S); iii-2) from the film of solution (S) obtained in step iii-1), evaporating at least one aprotic polar solvent to obtain a membrane (M) in the form of a film. The method of claim 1 , comprising:

9. 2. The process according to claim 1, wherein the separation of the at least one aprotic polar solvent from the solution (S) in step iii) is carried out by a phase inversion method.

10. A membrane (M) obtainable by the method according to any one of claims 1 to 9.

11. The membrane (M) according to claim 10, comprising at least one catalytic coating.

12. 11. A catalyst coated membrane comprising the membrane of claim 10, wherein the catalyst layers for the anode and cathode are coated on both sides of the membrane (M) using a catalyst dispersion containing a binder, the binder being selected from the group consisting of Nafion and Nafion-type polymers (PFSA), sulfonated polyarylene sulfone polymers (sP), and sulfonated styrene copolymers.

13. 13. The catalyst coated membrane according to claim 12, wherein the binder in the catalyst dispersion and the membrane (M) comprise the same sulfonated polyarylene sulfone polymer (sP).

14. A fuel cell comprising a membrane (M) according to claim 10.

15. Electrolysis or electrodialysis cell comprising a membrane (M) according to claim 10.

16. 11. Use of a membrane (M) according to claim 10 in an electrolysis cell, an electrodialysis cell or a fuel cell.

17. 11. A method for producing electrical energy and / or hydrogen using a membrane (M) according to claim 10.

Images