Process for preparation of sulfonated polyarylene sulfone polymers (sp)

Abstract

The present invention relates to a process for preparing a sulfonated polyarylene sulfone polymer (sP), to the sulfonated polyarylene sulfone polymer (sP) obtained by the process according to the invention, to a membrane (M) comprising the sulfonated polyarylene sulfone polymer (sP), to a process for preparing the membrane and to the use of the membrane (M) for separating gases from gas mixtures.

Description

[0001] The present invention relates to a process for preparing a sulfonated polyarylene sulfone polymer (sP), the sulfonated polyarylene sulfone polymer (sP) obtained by the process of the present invention, a membrane (M) comprising the sulfonated polyarylene sulfone polymer (sP), a process for preparing the membrane and the use of the membrane (M) for separating gases from gas mixtures.

[0002] Politics, society and industry aim to reduce CO2 emissions by decarbonizing industry and mobility. In this context, green hydrogen plays a strategic role due to its ability to replace hydrocarbons in chemical and industrial processes, energy conversion and fuel cell propulsion in mobility applications. Renewable electricity can be used to operate electrolyzers to produce green sustainable hydrogen.

[0003] The key components in electrolyzers and electrodialysis cells are the so-called polymer electrolyte membranes (PEMs), which have to meet several requirements. They need to be ionically conductive and at the same time they have to separate the gases hydrogen and oxygen. Furthermore, the membranes have to be robust and stable for long-term operation and lifetime, with constant performance.

[0004] Prior art membranes are mainly based on fluorinated polymers with sulfonic acid side chains (PFSA), which are marketed for example under the trade name Due to the complexity of PFSA production, these polymers are still quite expensive. In addition, the toxicity and persistence of fluorinated chemicals pose several challenges to the production, use and recycling of these materials. Therefore, science and industry try to develop more sustainable solutions to replace PFSA membranes.

[0005] A promising class of materials for these applications is polyarylene sulfone polymers. They belong to the group of high-performance polymers with high thermal resistance, chemical resistance, excellent mechanical properties and durability (EM Koch, H.-M. Walter, Kunststoffe 80 (1990) 1146; E. Kunststoffe 80, (1990) 1149, N. Inchaurondo-Nehm, Kunststoffe 98, (2008) 190).

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

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

[0008] General information on the formation of polyarylene sulfone polymers by the hydroxide process is found, inter alia, in RN Johnson et al., J. Polym. Sci. A-1 5 (1967) 2375, while the carbonate process is described in JEMcGrath et al., Polymer 25 (1984) 1827.

[0009] Processes for forming polyarylene sulfone polymers from aromatic bishalogen compounds and aromatic bisphenols or their salts in an aprotic solvent 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 297 363 and EP-A 135 130.

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

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

[0012] Sulfonated polyarylene sulfone polymers have been known for decades. Although direct sulfonation of polyarylene sulfone polymers causes side reactions and allows only limited control over 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 show several interesting properties for use as ion-conducting membranes in fuel cells or for electrolysis, the main problem that still has to be solved is the production method itself. One challenge is the extremely long reaction time and the large-scale inspection and separation of such copolymers, especially when a large amount of disulfonated monomers are used. The condensation produces a polymer suspension containing the sulfonated copolymer (sulfonated polyarylene sulfone polymer) and salt. After separation of the salt, precipitation is usually carried out in isopropanol to separate the sulfonated polyarylene sulfone polymer, which causes a large amount of solvent mixture to be reprocessed or disposed of. In addition, a part of the product is not completely precipitated and can cause clogging of the filter during subsequent separation. In addition, in order to produce a membrane, the sulfonated copolymer must be dissolved again.

[0014] The object of the present invention is therefore to provide a process for preparing sulfonated polyarylene sulfone polymers (sP) which does not retain the disadvantages of the prior art or retains the disadvantages of the prior art only in a reduced form. The process should be easy to implement. The sulfonated polyarylene sulfone polymers (sP) should be suitable for producing membranes, in particular membranes which are able to separate hydrogen from gas mixtures containing hydrogen.

[0015] This object is achieved by a method for preparing a sulfonated polyarylene sulfone polymer (sP), the method comprising the following steps:

[0016] i) making the reaction mixture (R G ) conversion, the reaction mixture comprising:

[0017] X moles of an aromatic dihalogen sulfone component (component A)), the aromatic dihalogen sulfone component comprising G ) in the aromatic dihalogen sulfone component

[0018] (component A)) total molar amount:

[0019] X 1 mol % of at least one sulfonated aromatic dihalogen sulfone (component (A1)), and

[0020] X 2 mol % of at least one non-sulfonated aromatic dihalogen sulfone (component (A2)),

[0021] in

[0022] X 1 In the range of 25 to 70, and X 2 In the range of 30 to 75,

[0023] Y moles of at least one aromatic dihydroxy compound (component (B)),

[0024] Z moles of at least one carbonate compound (component (C)),

[0025] in

[0026] The ratio of X to Y is in the range of 0.95 to 1.05,

[0027] And among them

[0028] Z is in the range of P to Q,

[0029] Where P is calculated according to the following formula:

[0030] P=Y*(1.05+X 1 / 100*1.05),

[0031] And where Q is calculated according to the following formula:

[0032] Q=Y*(1.05+X 1 / 100*1.4).

[0033] It has been surprisingly found that by using the carbonate compound in the amount according to the invention, the condensation time for preparing the sulfonated polyarylene sulfone polymer (sP) can be significantly reduced. In addition, sulfonated polyarylene sulfone polymers (sP) with high viscosity numbers are obtained by the process according to the invention. In addition, it has been surprisingly found that sulfonated polyarylene sulfone polymers (sP) can be used to produce membranes with good proton conductivity.

[0034] The present invention will be described in more detail below.

[0035] method

[0036] The sulfonated polyarylene sulfone polymer (sP) according to the present invention is preferably prepared by reacting a reaction mixture (R) comprising an aromatic dihalogen sulfone component, at least one aromatic dihydroxy compound and at least one carbonate compound. G ) conversion. In a preferred embodiment, the reaction mixture (R G ) further comprises at least one aprotic polar solvent.

[0037] The aromatic dihalogen sulfone component is also referred to as component (A). The terms "aromatic dihalogen sulfone component" and "component (A)" in the present invention are used synonymously and thus have the same meaning.

[0038] 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 thus have the same meaning.

[0039] The at least one carbonate compound is also referred to as component (C). The terms "at least one carbonate compound" and "component (C)" in the present invention are used synonymously and therefore have the same meaning.

[0040] 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.

[0041] Therefore, another object of the present invention is a process in which the reaction mixture (R G )) further comprises at least one aprotic polar solvent (component (D)).

[0042] Reaction mixture (R G) is a mixture provided for forming a sulfonated polyarylene sulfone polymer (sP). G ) are therefore all components involved in the mixture present before the polycondensation. By the polycondensation of component (A) and component (B), the polycondensation takes place so that the reaction mixture (R G ) is converted into the target product sulfonated polyarylene sulfone polymer (sP).

[0043] In step i), component (A) and component (B) enter into a polycondensation reaction. Component (C) acts as a base to deprotonate the hydroxyl groups of component (B). Component (D), if present, acts as a solvent.

[0044] The mixture obtained after polycondensation containing the target product of sulfonated polyarylene sulfone polymer (sP) is also referred to as product mixture (P G ). The product mixture (P G ) preferably further comprises a halide and preferably at least one aprotic polar solvent (component (D)). G ). During the conversion, component (C) reacts with component (B) to deprotonate component (B). Then, the deprotonated component (B) reacts with component (A), whereby a halide is formed. This process is known to those skilled in the art.

[0045] Reaction mixture (R G ) are preferably reacted simultaneously. The components can be mixed in an upstream step and then reacted. It is also possible to feed the components into a reactor, where they are mixed and then reacted.

[0046] In the process according to the invention, the reaction mixture (R G ) are preferably reacted simultaneously in step i). The reaction is preferably carried out in one stage. This means that the deprotonation of component (B) and the condensation reaction between component (A) and component (B) occur in a single reaction stage without isolating intermediate products, such as the deprotonated substance of component (B).

[0047] Furthermore, it is preferred that the reaction mixture (R G ) does not contain toluene or monochlorobenzene. Particularly preferably, the reaction mixture (R G ) does not contain any substance that forms an azeotrope with water.

[0048] The ratio of component (A) to component (B) results in principle from the stoichiometry of the polycondensation reaction which is carried out theoretically with elimination of hydrogen chloride and is established in a known manner by the person skilled in the art.

[0049] Preferably, the ratio of halogen end groups derived from component (A) to phenolic end groups derived from component (B) is adjusted by controlled establishment of an excess of component (B) relative to component (A) as starting compound.

[0050] More preferably, the molar ratio of component (B) to component (A) is from 0.95 to 1.08, especially from 0.98 to 1.06, most preferably from 0.985 to 1.05.

[0051] In a preferred embodiment, the ratio of X to Y is from 0.95 to 1.08, especially from 0.98 to 1.06, most preferably from 0.985 to 1.05.

[0052] More preferably, the molar ratio of component (A) to component (B) is from 0.99 to 1.01, especially from 0.992 to 1.008, most preferably from 0.995 to 1.005.

[0053] In a preferred embodiment, the ratio of X to Y is from 0.99 to 1.01, especially from 0.992 to 1.008, most preferably from 0.995 to 1.005.

[0054] Preferably, the conversion rate in the polycondensation reaction is at least 0.9.

[0055] Process step i) for preparing the sulfonated polyarylene sulfone polymer (sP) is preferably carried out under the conditions of the so-called "carbonate process". This means that the reaction mixture (R G ) under the conditions of the so-called "carbonate process". The polycondensation reaction is usually carried out at a temperature in the range of 80° C. to 250° C., preferably in the range of 100° C. to 220° C. The upper limit of the temperature 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 usually carried out at standard pressure. The reaction is preferably carried out within a time interval in the range of 0.5 hour to 14 hours, in particular 1 hour to 12 hours.

[0056] The product mixture (P G ) The separation of the obtained sulfonated polyarylene sulfone polymer (sP) obtained in the process can be carried out, for example, by subjecting the product mixture (P G ) is precipitated in water or a mixture of water and other solvents. The precipitated sulfonated polyarylene sulfone polymer (P) can then be extracted with water and then dried. In one embodiment of the invention, the precipitation can also be absorbed in an acidic medium. Suitable acids are, for example, organic or inorganic acids, for example carboxylic acids such as acetic acid, propionic acid, succinic acid or citric acid, and inorganic acids such as hydrochloric acid, sulfuric acid or phosphoric acid.

[0057] After step i), the product mixture (PG ) to remove the halide. The halide can be removed by means known in the art, such as filtration, centrifugation, decantation, etc.

[0058] Therefore, the present invention also provides a method, wherein the method further comprises the steps of

[0059] ii) treating the product mixture (P) obtained in step i) G ) by filtration, centrifugation or decantation.

[0060] In one embodiment, the conversion with an aliphatic organohalogen compound is carried out after the polycondensation. Thus, the reactive hydroxyl groups are terminated and the polymer is further stabilized. The conversion with an aliphatic organohalogen compound can be carried out before or after filtration.

[0061] Preferred aliphatic organohalogen compounds are alkyl halides, in particular alkyl chlorides, in particular primary alkyl chlorides, having a straight-chain or branched alkyl group containing 1 to 10 carbon atoms, particularly preferably methyl halides, in particular methyl chloride.

[0062] The reaction with the aliphatic organohalogen compound is preferably carried out at a temperature of 90° C. to 160° C., in particular 100° C. to 150° C. The time can vary widely and is generally at least 5 minutes, in particular at least 15 minutes. The reaction time is preferably 15 minutes to 8 hours, in particular 30 minutes to 4 hours.

[0063] Various methods can be used to add the aliphatic organohalogen compound. In addition, the amount of the aliphatic organohalogen compound added can be stoichiometric or represent an excess, wherein the excess can be, for example, up to a 5-fold excess. In a preferred embodiment, the aliphatic organohalogen compound is added continuously, particularly introduced continuously in the form of a gas stream.

[0064] Component (A)

[0065] Component (A), which is also referred to as the aromatic dihalogen sulfone component, comprises at least at least one sulfonated aromatic dihalogen sulfone and at least one non-sulfonated aromatic dihalogen sulfone.

[0066] 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.

[0067] 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.

[0068] Reference herein to "at least one sulfonated aromatic dihalogen sulfone" is intended to mean exactly one sulfonated aromatic dihalogen sulfone as well as mixtures of two or more sulfonated aromatic dihalogen sulfones. Preferably exactly one sulfonated aromatic dihalogen sulfone is used.

[0069] Reference herein to "at least one non-sulfonated aromatic dihalogen sulfone" is intended to mean exactly one non-sulfonated aromatic dihalogen sulfone as well as mixtures of two or more non-sulfonated aromatic dihalogen sulfones. Preferably exactly one non-sulfonated aromatic dihalogen sulfone is used.

[0070] "X" preferably means the reaction mixture (R G ) in the reaction mixture (R G ) is the total molar amount of the aromatic dihalogen sulfone component (component (A)). In other words, "X" preferably means the molar amount of the aromatic dihalogen sulfone component (component (A)) contained in component (A), preferably in the reaction mixture (R G ) is the sum of the molar amounts of component (A1) and component (A2) contained in the reaction mixture (R G ) in the total molar amount of component (A), "X 1 " means herein the molar amount of component (A1) in mol %, and "X 2 " refers herein to the molar amount of component (A2) in mol %.

[0071] In each case based on the reaction mixture (R G ) is based on the total molar amount of the aromatic dihalogen sulfone component (component (A)), X 1 It is usually in the range of 25 mol% to 70 mol%, preferably in the range of 27.5 mol% to 65 mol%, more preferably in the range of 30 mol% to 60 mol%, and most preferably in the range of 32.5 mol% to 57.5 mol%.

[0072] In each case based on the reaction mixture (R G ) is based on the total molar amount of the aromatic dihalogen sulfone component (component (A)), X 2 It is usually in the range of 30 mol% to 75 mol%, preferably in the range of 35 mol% to 72.5 mol%, more preferably in the range of 40 mol% to 70 mol%, and most preferably in the range of 42.5 mol% to 67.5 mol%.

[0073] X 1 and X 2 The amounts generally add up to 100 mol %.

[0074] Component (A1)

[0075] Component (A1) (which is also referred to as sulfonated aromatic dihalogen sulfone) preferably comprises at least one -SO3X 3 Group.

[0076] Component (A1) preferably contains at least one -SO3X 3 Group. In this article, "at least one -SO3X 3 "Group" means that component (A1) may contain exactly one -SO3X 3 group and two or more -SO3X 3 More preferably, component (A1) contains two -SO3X 3 Group.

[0077] General formula - SO3X 3 Contains sulfonic acid functional groups and derivatives of sulfonic acid functional groups such as sulfonates. 3 In the group, X 3 Can be hydrogen and / or a cation equivalent.

[0078] In the context of the present invention, reference to "a cation equivalent" means a cation of a single positive charge or a charge equivalent of a cation with two or more positive charges, such as Li, Na, K, Mg, Ca, NH4, preferably Na, K. Particularly preferred are Na or K.

[0079] Component (A1) is preferably selected from the group consisting of 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid and 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid and derivatives thereof.

[0080] In the context of the present invention, the terms "sulfonic acid" and "-SO3X 3 The term "sulfonic acid" in 4,4'-dichlorodiphenylsulfone-3,3'-disulfonic acid and 4,4'-difluorodiphenylsulfone-3,3'-disulfonic acid means "-SO3X 3 Group", where X 3 is hydrogen or a cation equivalent.

[0081] In one embodiment, component (A1) preferably comprises -SO3X with a cation equivalent 3 Particularly preferably, component (A1) is selected from the group consisting of 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid disodium salt, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt, 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid, 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid disodium salt and 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt.

[0082] Therefore, another object of the present invention is a process, wherein component (A1) comprises at least one compound selected from the group consisting of: 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid disodium salt, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt, 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid, 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid disodium salt and 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt.

[0083] In one embodiment, based on the reaction mixture (R G ) in the total weight of component (A1), component (A1) comprises not less than 70 wt%, preferably not less than 90 wt%, and more preferably not less than 98 wt% of at least one aromatic dihalogen sulfone component, the at least one aromatic dihalogen sulfone component comprising at least one -SO3X selected from the group consisting of 3 Groups: 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid disodium salt, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt, 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid, 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid disodium salt and 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt.

[0084] In another particularly preferred embodiment, component (A1) consists essentially of at least one aromatic dihalogen sulfone comprising at least one -SO3X selected from the group consisting of 3 Groups: 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid disodium salt, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt, 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid, 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid disodium salt and 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt. In this context, "essentially consisting of..." means that the reaction mixture (R G ) in the total weight of component (A2), component (A2) comprises more than 97% by weight, preferably more than 98% by weight, and more preferably more than 99% by weight of at least one aromatic dihalogen sulfone, the at least one aromatic dihalogen sulfone comprising at least one -SO3X selected from the group consisting of 3Groups: 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid disodium salt, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt, 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid, 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid disodium salt and 4,4'-difluorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt.

[0085] In these embodiments, 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt and 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid disodium salt are particularly preferred for use as component (A1).

[0086] In another particularly preferred embodiment, component (A1) consists of 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid dipotassium salt or 4,4'-dichlorodiphenyl sulfone-3,3'-disulfonic acid disodium salt.

[0087] Component (A2)

[0088] Component (A2) (which is also referred to as the non-sulfonated aromatic dihalogen sulfone component) preferably does not contain -SO3X 3 Group.

[0089] Preferably, based on the reaction mixture (R G ) in the total weight of component (A2), component (A2) comprises not less than 80% by weight, preferably not less than 90% by weight, and more preferably not less than 98% by weight of at least one aromatic dihalogen sulfone selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone. The weight percentages related to component (A2) here further relate to the sum of the 4,4'-dichlorodiphenyl sulfone used and the 4,4'-difluorodiphenyl sulfone used.

[0090] Therefore, another object of the present invention is a process in which, based on the reaction mixture (R G ) in the present invention, component (A2) contains not less than 80 wt % of at least one aromatic dihalogen sulfone selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone, based on the total weight of component (A2) in the present invention.

[0091] In another particularly preferred embodiment, component (A2) consists essentially of at least one aromatic dihalogen sulfone selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone. G) in the total weight of component (A2), component (A2) comprises more than 99% by weight, preferably more than 99.5% by weight, and more preferably more than 99.9% by weight of at least one aromatic dihalogen sulfone selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone. In these embodiments, 4,4'-dichlorodiphenyl sulfone is particularly preferred for use as component (A2).

[0092] In another particularly preferred embodiment, component (A2) consists essentially of 4,4'-dichlorodiphenyl sulfone. Reference herein to "essentially consisting of..." means that component (A2) contains more than 99% by weight, preferably more than 99.5% by weight, and more preferably more than 99.9% by weight of 4,4'-dichlorodiphenyl sulfone. In another particularly preferred embodiment, component (A2) consists of 4,4'-dichlorodiphenyl sulfone.

[0093] Preferably, component (A2) is selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone.

[0094] Component (B)

[0095] Component (B), which is also referred to as an aromatic dihydroxy compound, generally comprises two hydroxyl groups.

[0096] Reference herein to "at least one aromatic dihydroxy compound" is intended to mean exactly one aromatic dihydroxy compound as well as mixtures of two or more aromatic dihydroxy compounds. Preferably exactly one aromatic dihydroxy compound is used.

[0097] "Y" preferably means the reaction mixture (R G ) in the reaction mixture (R G ) is the total molar amount of the aromatic dihydroxy compound (component (B)).

[0098] 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. From among the above aromatic dihydroxy components, 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone, bisphenol A are preferred, and 4,4'-dihydroxybiphenyl is particularly preferred.

[0099] Therefore, the present invention also provides a process, wherein component (B) is selected from the group consisting of 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone, bisphenol A, 4,4'-dihydroxybenzophenone and hydroquinone.

[0100] Preferably, based on the reaction mixture (R G ) in the total weight of component (B), component (B) contains not less than 80 wt%, preferably not less than 90 wt%, and more preferably not less than 98 wt% of 4,4'-dihydroxybiphenyl.

[0101] Therefore, another object of the present invention is a process in which, based on the reaction mixture (R G ) in the total weight of component (B), component (B) contains not less than 80 wt% of 4,4'-dihydroxybiphenyl.

[0102] The percentages by weight relating to component (B) here further relate to the sum of the 4,4′-dihydroxybiphenyl, 4,4′-dihydroxydiphenyl sulfone, bisphenol A (2,2-bis-(4-hydroxyphenyl)-propane), 4,4′-dihydroxybenzophenone and hydroquinone used.

[0103] In another particularly preferred embodiment, component (B) consists essentially of 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-hydroxy-phenyl)propane), 4,4'-dihydroxybenzophenone and hydroquinone. In this context, "essentially consisting of" means that the aromatic dihydroxy component is selected from the group consisting of: 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl sulfone, bisphenol A (2,2-bis(4-hydroxy-phenyl)propane), 4,4'-dihydroxybenzophenone and hydroquinone. G ) in the total weight of component (B), component (B) comprises more than 98 wt%, preferably more than 99.0 wt%, and more preferably more than 99.5 wt% of 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. In these embodiments, 4,4'-dihydroxybiphenyl, bisphenol A and 4,4'-dihydroxydiphenyl sulfone are particularly preferred for use as component (B), and 4,4'-dihydroxybiphenyl is most preferred.

[0104] Component (C)

[0105] 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.

[0106] 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.

[0107] For example, based on the reaction mixture (R G ), component (C) comprises not less than 50 wt. %, more preferably not less than 70 wt. %, and most preferably not less than 90 wt. % potassium carbonate, based on the total weight of the at least one carbonate component in the composition.

[0108] Therefore, another object of the present invention is a process in which, based on the reaction mixture (R G ) in the present invention, the component (C) contains not less than 50 wt % potassium carbonate, based on the total weight of the component (C) in the present invention.

[0109] In a preferred embodiment, component (C) consists of potassium carbonate. Potassium carbonate having a volume-weighted average 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 preferably potassium carbonate. The volume-weighted average particle size of potassium carbonate is determined using a particle size analyzer in a suspension of potassium carbonate in a mixture of chlorobenzene / sulfolane (60 / 40 by weight).

[0110] "Z" preferably means the reaction mixture (R G ) in the reaction mixture (R G ) in the total molar amount of at least one carbonate component (component (C)).

[0111] Z is in the range of P to Q.

[0112] "P" is calculated according to the following formula:

[0113] P=Y*(1.05+X 1 / 100*1.05)

[0114] In this formula, Y is the reaction mixture (R G ) in the molar amount of component (B), and X 1 is the reaction mixture (R G ) is the value of the mol % of component (A1) in ).

[0115] "Q" is calculated according to the following formula:

[0116] Q=Y*(1.05+X 1 / 100*1.4)

[0117] In this formula, Y is also the reaction mixture (R G ) in the molar amount of component (B), and X 1 Also the reaction mixture (R G ) is the value of the mol % of component (A1) in ).

[0118] For the composition used in Inventive Example 3, P was 2.82 and Q was 3.06. Therefore, Z ranged from 2.82 to 3.06 and 2.9 moles were used.

[0119] Component (D)

[0120] Reaction mixture (R G ) preferably comprises at least one aprotic polar solvent as component (D). According to the invention, "at least one aprotic polar solvent" is understood to mean exactly one aprotic polar solvent and also mixtures 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.

[0121] Suitable aprotic polar solvents are, for example, selected from anisole, dimethylformamide, dimethyl sulfoxide, sulfolane, N-methylpyrrolidone, N-ethylpyrrolidone and N-dimethylacetamide.

[0122] Preferably, component (D) is selected from the group consisting of: N-methylpyrrolidone, N-dimethylacetamide, dimethyl sulfoxide and dimethylformamide. N-methylpyrrolidone is particularly preferred as component (D).

[0123] Preferably, based on the reaction mixture (R G ), component (D) contains not less than 50 wt %, preferably not less than 70 wt %, and more preferably not less than 90 wt % of at least one solvent selected from the group consisting of: N-methylpyrrolidone, N-dimethylacetamide, dimethyl sulfoxide and dimethylformamide. N-methylpyrrolidone is particularly preferred as component (D).

[0124] Therefore, another object of the present invention is a process in which, based on the reaction mixture (R G ), based on the total weight of component (D) in the composition, component (D) contains not less than 50 wt % of at least one solvent selected from the group consisting of N-methylpyrrolidone, N-dimethylacetamide, dimethyl sulfoxide and dimethylformamide.

[0125] In a preferred embodiment, component (D) consists of N-methylpyrrolidone, which is also known as NMP or N-methyl-2-pyrrolidone.

[0126] Sulfonated polyarylene sulfone polymer (sP)

[0127] Sulfonated polyarylene sulfone polymers (sP) are a class of polymers known to the person skilled in the art. In principle, any sulfonated polyarylene sulfone polymer (sP) known to the person skilled in the art and / or producible by known methods can be used. Suitable methods for preparing sulfonated polyarylene sulfone polymers (sP) are explained at a later stage below. Preferred sulfonated polyarylene sulfone polymers (sP) comprise repeating units of the general formula I:

[0128]

[0129] in

[0130] t and q: each independently 0, 1, 2 or 3,

[0131] Q 1 , T and Y 1 : are each independently a chemical bond or selected from -O-,

[0132] -S-, -SO2-, -S(=O)-, -C(=O)-, -N=N- and -CR a R b -, where R a and R b are independently a hydrogen atom or a C1-C 12 -alkyl, C1-

[0133] C 12 -alkoxy or C6-C 18 - an aryl group, and wherein Q, T and Y

[0134] At least one of them is -SO2-,

[0135] Ar and Ar 1 : Each independently is C6-C 18 Aryl, wherein the C6-C 18 The aryl group is unsubstituted or substituted by at least one substituent selected from the group consisting of: C1-

[0136] C 12 Alkyl, C1-C 12 Alkoxy, C6-C 18 Aryl, halogen and -SO-3X, p, m, n and k: each independently 0, 1, 2, 3 or 4, provided that the sum of p, m, n and k is not less than 1, and

[0137] X 3 : is hydrogen or a cation equivalent.

[0138] Therefore, another object of the present invention is a sulfonated polyarylene sulfone polymer (sP), wherein the sulfonated polyarylene sulfone polymer (sP) comprises repeating units of the general formula (I):

[0139]

[0140] in

[0141] t and q: are each independently 0, 1, 2 or 3,

[0142] Q 1 , T and Y 1 : Each independently is a chemical bond or selected from -O-, -S-, -SO2-,

[0143] -S(=O)-, -C(=O)-, -N=N- and -CR a R b -,

[0144] Where R a and R b are independently a hydrogen atom or a C1-C 12 -alkyl,

[0145] C1-C 12 -alkoxy or C6-C 18 -aryl group, and wherein Q, T

[0146] At least one of Y is -SO2-,

[0147] Ar and Ar 1 : Each independently is C6-C 18 Aryl, wherein the C6-C 18 The aryl group is unsubstituted or substituted by at least one substituent selected from the group consisting of: C1-

[0148] C 12 Alkyl, C1-C 12 Alkoxy, C6-C 18 Aryl, halogen and -SO-3X, p, m, n and k: each independently 0, 1, 2, 3 or 4, provided that the sum of p, m, n and k is not less than 1, and

[0149] X 3 : is hydrogen or a cation equivalent.

[0150] In a preferred embodiment, the sulfonated polyarylene sulfone polymer (sP) comprises at least 80 wt.-%, based on the total weight of the sulfonated polyarylene sulfone polymer (sP), of recurring units of the general formula (I).

[0151] If under the above premise, Q1 , T or Y 1 is a chemical bond, then this means that the adjacent group on the left-hand side and the adjacent group on the right-hand side are directly connected to each other by a chemical bond.

[0152] R a and R b are independently hydrogen or C1-C 12 alkyl.

[0153] Preferred C1-C 12 Alkyl groups include straight and branched saturated alkyl groups having 1 to 12 carbon atoms. The following moieties are particularly suitable: C1-C6 alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, 2-methylpentyl or 3-methylpentyl, and relatively long chain moieties such as unbranched heptyl, octyl, nonyl, decyl, undecyl, lauryl, and branched analogs thereof.

[0154] C1-C used 12 The alkyl moiety in the alkoxy group includes the alkyl groups having 1 to 12 carbon atoms as defined above. The cycloalkyl moieties preferably used include in particular C3-C 12 Cycloalkyl moieties, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclopropylmethyl, cyclopropylethyl, cyclopropylpropyl, cyclobutylmethyl, cyclobutylethyl, cyclopentylethyl, cyclopentylpropyl, cyclopentylbutyl, cyclopentylpentyl, cyclopentylhexyl, cyclopentylcyclohexylmethyl, -cyclopentyldimethyl, cyclopentyltrimethyl.

[0155] Ar and Ar 1 Each independently is C6-C 18 Aryl. From the starting materials below, Ar is preferably derived from an electron-rich aromatic substance that is very susceptible to electrophilic attack, preferably selected from the group consisting of sulfonated or non-sulfonated hydroquinone, resorcinol, dihydroxynaphthalene, especially 2,7-dihydroxynaphthalene and 4,4'-bisphenol. Ar 1 Preferably, it is unsubstituted C6 or C 12 Arylene group.

[0156] In a preferred embodiment, Ar and Ar of formula (I) 1 Preferably they are each independently selected from the group consisting of sulfonated or non-sulfonated 1,4-phenylene, 1,3-phenylene, naphthylene, in particular 2,7-dihydroxynaphthalene and 4,4′-biphenylene.

[0157] Preferred are sulfonated polyarylene sulfone polymers (sP) having one or more of the following structural units (Ia) to (Io):

[0158]

[0159]

[0160] wherein l, k, m, n, o, p are each independently 0, 1, 2, 3 or 4, provided that the sum of l, k, m, n, o and p is ≥ 1, and

[0161] X 3 is hydrogen or a cation equivalent.

[0162] In the context of the present invention, reference to "a cation equivalent" means a cation of a single positive charge or a charge equivalent of a cation carrying two or more positive charges, such as Li, Na, K, Mg, Ca, NH4, preferably Na, K.

[0163] In addition to the preferred building blocks (Ia) to (Io), preference is also given to those structural units in which one or more sulfonated or nonsulfonated 1,4-dihydroxyphenyl units are replaced by resorcinol or dihydroxynaphthalene.

[0164] Copolymers composed of various combinations of structural units or composed of sulfonated and non-sulfonated structural units are also useful.

[0165] In particularly preferred cases, the structural units (Ia), (Ib), (Ig) and (Ik) or copolymers thereof are used as repeating units of the general formula (I).

[0166] In a particularly preferred embodiment, Ar is 1,4-phenylene, t is 1, T is a chemical bond, and Y 1 is -SO2-, q is 0, p is 0, m is 0, n is 1 and k is 1. Sulfonated polyphenylene sulfone composed of the above-mentioned structural repeating units is represented by sPPSU.

[0167] 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 this listed structural repeating unit are referred to as sulfonated polyetherethersulfones (sPEES).

[0168] In an advantageous embodiment, the sulfonated polyarylene sulfone polymer (sP) comprises:

[0169] The non-sulfonated repeating unit of formula (1)

[0170]

[0171] and the sulfonated repeating unit of formula (2)

[0172]

[0173] Specifically, the sulfonated polyarylene sulfone polymer (sP) consists exclusively of non-sulfonated repeating units of formula (1) and sulfonated repeating units of formula (2).

[0174] In a very advantageous embodiment, the sulfonated polyarylene sulfone polymer (sP) comprises:

[0175] The non-sulfonated repeating unit of formula (1a)

[0176]

[0177] and the sulfonated repeating unit of formula (1b)

[0178]

[0179] Specifically, the sulfonated polyarylene sulfone polymer (sP) consists exclusively of non-sulfonated repeating units of formula (1a) and sulfonated repeating units of formula (1b).

[0180] The sulfonated polyarylene sulfone polymers (sP) used according to the invention preferably have a viscosity number of 20 ml / g to 250 ml / g, preferably 50 ml / g to 200 ml / g. The viscosity number is quantified in accordance with DIN EN ISO 1628-1 in a 1% solution in N-methyl-pyrrolidone (NMP) at 25° C. The measurement can also be carried out at lower polymer concentrations (e.g. 0.5%).

[0181] The weight average molecular weight (M) of the sulfonated polyarylene sulfone polymer (sP) used in the process of the present invention is W ) is generally in the range of 10 000 g / mole to 250 000 g / mole, preferably in the range of 15 000 g / mole to 200 000 g / mole, and more preferably in the range of 18 000 g / mole to 150 000 g / mole. The weight average molecular weight (M) is measured using gel permeation chromatography (GPC). W ). Dimethylacetamide (DMAc) was used as a solvent, and narrow distribution polymethyl methacrylate was used as a standard in the measurement.

[0182] The sulfonated polyarylene sulfone polymer (sP) according to the invention preferably has a viscosity number equal to or greater than 80 ml / g, preferably equal to or greater than 85 ml / g and particularly preferably equal to or greater than 90 ml / g. The viscosity number is quantified in accordance with DIN EN ISO 1628-1 in a 0.5% solution in N-methyl-pyrrolidone (NMP) at 25°C.

[0183] The sulfonated polyarylene sulfone polymers (sP) according to the invention preferably have a viscosity number of 80 to 150 ml / g, preferably 85 to 140 ml / g. The viscosity number is quantified in 0.5% N-methyl-pyrrolidone (NMP) solution at 25° C. according to DIN EN ISO 1628-1.

[0184] The weight average molecular weight (M) of the sulfonated polyarylene sulfone polymer (sP) used in the process of the present invention is W ) is generally in the range of 40 000 g / mole to 250 000 g / mole, preferably in the range of 50 000 g / mole to 200 000 g / mole, and more preferably in the range of 60 000 g / mole to 150 000 g / mole. The weight average molecular weight (M) is measured using gel permeation chromatography (GPC). W ). Dimethylacetamide (DMAc) was used as a solvent, and narrow distribution polymethyl methacrylate was used as a standard in the measurement.

[0185] Another object of the present invention is therefore the sulfonated polyarylene sulfone polymer (sP) obtainable by the process of the present invention.

[0186] Another object of the present invention is therefore sulfonated polyarylene sulfone polymers (sP) comprising recurring units of the general formula (I).

[0187] In another embodiment, X 3 For X 3a or X 3b .

[0188] Another object of the present invention is a sulfonated polyarylene sulfone polymer (sP) comprising repeating units comprising at least one -SO3X 3a group and / or at least one -SO3X 3b Group, where X 3a and X 3b Each independently of the other is at least one selected from the group consisting of: hydrogen and a cation equivalent, wherein X contained in the sulfonated polyarylene sulfone polymer (sP) 3a and X 3b At least 50 mol % of the total amount is potassium cations.

[0189] It has surprisingly been found that membranes with good proton conductivity can be prepared from the sulfonated polyarylene sulfone polymers (sP) of the invention. In addition, the membranes (M) surprisingly show less water swelling and less size change than membranes prepared from sulfonated polyarylene sulfone polymers known in the prior art.

[0190] The sulfonated polyarylene sulfone polymer (sP) according to the present invention contains repeating units, wherein the repeating units contain at least one -SO3X 3a group and / or at least one -SO3X 3b In this case, the group contains at least one -SO3X 3a group and / or at least one -SO3X 3b The repeating units of the repeating units of the group are also called sulfonated repeating units.

[0191] The sulfonated polyarylene sulfone polymer (sP) according to the present invention may contain sulfonated repeating units and non-sulfonated repeating units. Non-sulfonated repeating units are understood to mean those that do not contain -SO3X 3a and-SO3X 3b Repeating unit of a group.

[0192] In a preferred embodiment, the sulfonated polyarylene sulfone polymer (sP) contains sulfonated repeat units in a range of 25 mol % to 70 mol %, preferably in a range of 27.5 mol % to 65 mol %, more preferably in a range of 30 mol % to 60 mol % and most preferably in a range of 32.5 mol % to 57.5 mol %, based in each case on the total molar amount of the sulfonated polyarylene sulfone polymer (sP).

[0193] In a preferred embodiment, the sulfonated polyarylene sulfone polymer (sP) contains in a range of 30 mol % to 75 mol %, preferably in a range of 35 mol % to 72.5 mol %, more preferably in a range of 40 mol % to 70 mol % and most preferably in a range of 42.5 mol % to 67.5 mol %, of non-sulfonated repeat units, based in each case on the total molar amount of the sulfonated polyarylene sulfone polymer (sP).

[0194] The amount of sulfonated repeating units and non-sulfonated repeating units in the sulfonated polyarylene sulfone polymer (sP) generally adds up to 100 mol%.

[0195] In this case, the term "at least one -SO3X 3a Group" and "at least one -SO3X 3b The term "at least one -SO3X" is included in 3 The term "at least one -SO3X 3 "Group" may mean "at least one -SO3X 3a group" and / or "at least one -SO3X 3b Group".

[0196] In this article, "X 3a ” and “X 3b ” included in “X3 ". The term "at least one -SO3X 3 "Group" may mean "at least one -SO3X 3a group" and / or "at least one -SO3X 3b Group".

[0197] All targets for "at least one -SO3X 3 The explanation of "at least one -SO3X 3a Group" and "at least one -SO3X 3b Group".

[0198] In addition, all 3 The explanation of "X" also applies to 3a ” and “X 3b ”.

[0199] In this context, the term "at least one -SO3X 3 "Group" is understood to mean exactly one -SO3X 3 groups and two, three or four -SO3X 3 In a preferred embodiment, the sulfonated repeating unit contains 1 to 4 -SO3X 3 Group, more preferably 1 to 3 -SO3X 3 Groups, and particularly preferably 1 to 2 -SO3X 3 In a particularly preferred embodiment, the sulfonated repeating unit contains 2 -SO3X 3 Group.

[0200] X 3a and X 3b are each independently of one another at least one member selected from the group consisting of hydrogen and a cation equivalent. In the context of the present invention, in each case X contained in the sulfonated polyarylene sulfone polymer (sP) 3a and X 3b The term "cation equivalent" means a cation of a single positive charge or a charge equivalent of a cation with two or more positive charges, such as Li, Na, K, Mg, Ca, NH4, preferably Na, K, with the proviso that at least 50 mol%, more preferably at least 55 mol%, even more preferably 60 to 80 mol%, and particularly preferably 62.5 to 77.5 mol% of the total amount of potassium cations.

[0201] In a very advantageous embodiment, the sulfonated polyarylene sulfone polymer (sP) comprises:

[0202] The non-sulfonated repeating unit of formula (1a)

[0203]

[0204] and the sulfonated repeating unit of formula (1b)

[0205]

[0206] Specifically, the sulfonated polyarylene sulfone polymer (sP) consists exclusively of non-sulfonated repeating units of formula (1a) and sulfonated repeating units of formula (1b).

[0207] The sulfonated polyarylene sulfone polymer (sP) is suitable for preparing the membrane (M).The sulfonated polyarylene sulfone polymer (sP) obtained by the process of the present invention can be used in the membrane (M).

[0208] Another object of the present invention is therefore also the use of the sulfonated polyarylene sulfone polymer (sP) obtainable by the process of the invention in a membrane (M).

[0209] The membrane (M) can be prepared from the sulfonated polyarylene sulfone polymer (sP) according to the invention by any method known to the person skilled in the art.

[0210] Preferably, the membrane (M) comprising the sulfonated polyarylene sulfone polymer (sP) obtainable by the process of the present invention is prepared by a process comprising the following steps:

[0211] i) providing a solution (S) comprising a sulfonated polyarylene sulfone polymer (sP) and at least one solvent,

[0212] ii) separating the at least one solvent from the solution (S) to obtain a membrane (M).

[0213] Therefore, another object of the present invention is a process for preparing a membrane (M) comprising the sulfonated polyarylene sulfone polymer (sP) obtained by the process of the present invention, comprising the following steps:

[0214] i) providing a solution (S) comprising the sulfonated polyarylene sulfone polymer (sP) obtained by the process of the present invention and at least one solvent,

[0215] ii) separating the at least one solvent from the solution (S) to obtain a membrane (M).

[0216] Another object of the present invention is a membrane (M) comprising the sulfonated polyarylene sulfone polymer (sP) obtainable by the process described above.

[0217] Another object of the present invention is a membrane (M) comprising the sulfonated polyarylene sulfone polymer (sP) obtained by the process of the present invention.

[0218] The membrane (M) preferably comprises at least 50 wt% sulfonated polyarylene sulfone polymer (sP), more preferably at least 70 wt% and most preferably at least 90 wt% sulfonated polyarylene sulfone polymer (sP), based on the total weight of the membrane (M).

[0219] The membrane (M) is suitable for separating a gas from a gas mixture, in particular for separating hydrogen from a gas mixture containing hydrogen.

[0220] Therefore, another object of the present invention is the use of the membrane (M) obtained by the process of the present invention for separating gases from gas mixtures.

[0221] The present invention is more particularly illustrated by the following examples without being restricted thereto.

[0222] Components used :

[0223] DCDPS 4,4'-Dichlorodiphenyl sulfone,

[0224] sDCDPS 4,4'-Dichlorodiphenyl sulfone-3,3'-disulfonic acid disodium salt

[0225] BP 4,4'-dihydroxybiphenyl,

[0226] K2CO3: Potassium carbonate, anhydrous, average particle size 32.6 μm

[0227] NMP: N-Methylpyrrolidone, anhydrous

[0228] The viscosity number VN of the sulfonated polyarylene sulfone polymers (sP) was measured in 0.5% by weight NMP solution in accordance with DIN ISO 1628-1.

[0229] In CDCl3 by 1 H-NMR was used to determine the incorporation rate (incorporation rate) of sDCDPS. 1 The polymer content of the polymer solution after filtration was quantified by H-NMR.

[0230] The counterion content was determined by atomic spectroscopy.

[0231] Unless otherwise indicated, the separation of the sulfonated polyarylene sulfone polymer (sP) was carried out by dropping a solution of the sulfonated polyarylene sulfone polymer (sP) in NMP into isopropanol at room temperature. The drop height was 0.5 m. The throughput was about 2.5 l / hour. The precipitate obtained was then extracted with water at 85° C. (water throughput 160 l / h) for twenty hours. The material was then heated to below the glass transition temperature T g The mixture was dried at a temperature of 100 °C to a residual moisture content of less than 2% by weight.

[0232] The product mixture (P) was filtered in a heated metal pressure filter using a filter with a pore size of 5 μm and a N2 pressure of 3 bar. G The filter was heated to 60° C. to reduce the viscosity of the reaction mixture.

[0233] The yield of sulfonated polyarylene sulfone polymer (sP) after precipitation was determined gravimetrically.

[0234] Comparative Example 1 :

[0235] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 384.794 g (1.34 mol) of DCDPS, 343.875 g (0.7 mol) of sDCDPS, 372.42 g (2.00 mol) of BP and 304.052 g (2.20 mol) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 1250 ml of NMP in a nitrogen atmosphere.

[0236] The mixture was heated to 190° C. within one hour. In the following, reaction time is understood to mean the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation.

[0237] After 16 hours of reaction time, the reaction was stopped by adding 1750 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained was then precipitated in isopropanol, the resulting polymer precipitate was separated, and then extracted with hot water (85° C.) for 20 h. The material was then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0238] Comparative Example 2 :

[0239] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 384.794 g (1.34 mol) of DCDPS, 343.875 g (0.7 mol) of sDCDPS, 372.42 g (2.00 mol) of BP and 345.525 g (2.50 mol) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 1250 ml of NMP in a nitrogen atmosphere.

[0240] The mixture was heated to 190° C. within one hour. In the following, reaction time is understood to mean the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation.

[0241] After 16 hours of reaction time, the reaction was stopped by adding 1750 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained was then precipitated in isopropanol, the resulting polymer precipitate was separated, and then extracted with hot water (85° C.) for 20 h. The material was then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0242] Example 3 :

[0243] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 384.794 g (1.34 mol) of DCDPS, 343.875 g (0.7 mol) of sDCDPS, 372.42 g (2.00 mol) of BP and 400.809 g (2.90 mol) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 1250 ml of NMP in a nitrogen atmosphere.

[0244] The mixture was heated to 190° C. within one hour. In the following, reaction time is understood to mean the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation.

[0245] After 8.5 hours of reaction time, the reaction was stopped by adding 1750 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained was then precipitated in isopropanol, the resulting polymer precipitate was separated, and then extracted with hot water (85° C.) for 20 h. The material was then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0246] Example 4 :

[0247] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 258.444 g (0.900 mol) of DCDPS, 309.487 g (0.63 mol) of sDCDPS, 279.315 g (1.50 mol) of BP and 321.338 g (2.325 mol) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 938 ml of NMP in a nitrogen atmosphere.

[0248] The mixture was heated to 190° C. within one hour. In the following, reaction time is understood to mean the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation.

[0249] After 8.5 hours of reaction time, the reaction was stopped by adding 2312 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained was then precipitated in isopropanol, the resulting polymer precipitate was separated, and then extracted with hot water (85° C.) for 20 h. The material was then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0250] Example 5 :

[0251] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 223.985 g (0.78 mol) of DCDPS, 368.327 g (0.75 mol) of sDCDPS, 279.315 g (1.50 mol) of BP and 345.525 g (2.5 mol) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 938 ml of NMP in a nitrogen atmosphere.

[0252] The mixture was heated to 190° C. within one hour. In the following, reaction time is understood to mean the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation.

[0253] After 8.5 hours of reaction time, the reaction was stopped by adding 2312 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained was then precipitated in isopropanol, the resulting polymer precipitate was separated, and then extracted with hot water (85° C.) for 20 h. The material was then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0254] Comparative Example 6 :

[0255] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 223.985 g (0.78 mol) of DCDPS, 368.327 g (0.75 mol) of sDCDPS, 279.315 g (1.50 mol) of BP and 414.63 g (3 mol) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 938 ml of NMP in a nitrogen atmosphere.

[0256] The mixture was heated to 190° C. within one hour. In the following, reaction time is understood to mean the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation.

[0257] After 8.5 hours of reaction time, the reaction was stopped by adding 2312 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained was then precipitated in isopropanol, the resulting polymer precipitate was separated, and then extracted with hot water (85° C.) for 20 h. The material was then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0258] Table 1 :

[0259] C1 C2 3 4 5 C6 Condensation time [h] 16 16 8.5 8.5 8.5 8.5 <![CDATA[R G sDCDPS content in [mol %]]]> 34.3 34.3 34.3 41.2 49.0 49.0 <![CDATA[R G DCDPS content in [mol %]]]> 65.7 65.7 65.7 58.8 51.0 51.0 VN[ml / g] 37.8 45.2 70.8 72.0 69.9 61.0 sDCDPS content in sP [mol %] 30.5 30.6 32.5 38.8 46.9 44.8 Filter time [h] 11 14 16 15 17 >24 Yield [weight %] 68 72 88 81 80 72 Z [mole] K2CO3 2.2 2.5 2.9 2.325 2.5 3

[0260] By using the inventive amount of potassium carbonate, high molecular weight sulfonated polyarylene sulfone polymers (sP) with high amounts of incorporated sDCDPs can be prepared. Surprisingly, the filtration time of the high molecular weight sulfonated polyarylene sulfone polymers (sP) obtained by the process of the present invention is lower than the filtration time observed for high molecular weight products obtained with a higher excess of potassium carbonate.

[0261] Comparative Example 7 (C7) :

[0262] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 288.606 g (1.005 moles) of DCDPS, 257.90 g (0.525 moles) of sDCDPS, 279.315 g (1.500 moles) of BP and 248.778 (1.80 moles) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 938 ml of NMP in a nitrogen atmosphere.

[0263] The mixture was heated to 190° C. within one hour. In the following, the reaction time is understood to be the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation, and the losses in NMP were replaced.

[0264] After 8 hours of reaction time, the reaction was stopped by adding 1312 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained 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 h. The beads were then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0265] Comparative Example 8 (C8) :

[0266] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 288.606 g (1.005 moles) of DCDPS, 257.90 g (0.5250 moles) of sDCDPS, 279.315 g (1.50 moles) of BP and 310.97 g (2.25 moles) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 938 ml of NMP in a nitrogen atmosphere.

[0267] The mixture was heated to 190° C. within one hour. In the following, the reaction time is understood to be the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation, and the losses in NMP were replaced.

[0268] After 6.5 hours of reaction time, the torque reached a steady state, so that the reaction was stopped by adding 1312 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained 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 20h. The beads were then dried at 120°C for 24h under reduced pressure (<100 mbar).

[0269] Comparative Example 9 (C9) :

[0270] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 288.60 g (1.005 mol) of DCDPS, 257.90 g (0.525 mol) of sDCDPS, 279.315 g (1.50 mol) of BP and 248.778 g (1.80 mol) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 938 ml of NMP in a nitrogen atmosphere.

[0271] The mixture was heated to 190° C. within one hour. In the following, the reaction time is understood to be the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation, and the losses in NMP were replaced.

[0272] After 8 hours of reaction time, the reaction was stopped by adding 1312 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained 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 h. The beads were then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0273] Example 10 :

[0274] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 281.273 g (0.9795 mol) of DCDPS, 257.90 g (0.525 mol) of sDCDPS, 279.315 g (1.500 mol) of BP and 310.973 (2.25 mol) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 938 ml of NMP in a nitrogen atmosphere.

[0275] The mixture was heated to 190° C. within one hour. In the following, the reaction time is understood to be the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation, and the losses in NMP were replaced.

[0276] After a reaction time of 5.7 hours, the reaction was stopped by adding 1312 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained 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 h. The beads were then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0277] Embodiment 11 :

[0278] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 279.981 g (0.975 mol) of DCDPS, 257.90 g (0.525 mol) of sDCDPS, 279.315 g (1.500 mol) of BP and 310.973 (2.25 mol) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 938 ml of NMP in a nitrogen atmosphere.

[0279] The mixture was heated to 190° C. within one hour. In the following, the reaction time is understood to be the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation, and the losses in NMP were replaced.

[0280] After a reaction time of 5.4 hours, the reaction was stopped by adding 1312 ml of NMP and cooling to room temperature (within one hour). The potassium chloride formed in the reaction was removed by filtration. The polymer solution obtained 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 h. The beads were then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0281] Comparative Example 12 (C12) :

[0282] In a 4-liter glass reactor equipped with a thermometer, a gas inlet tube and a Dean-Stark separator, 255.52 g (1.005 mol) of DFDPS, 257.90 g (0.525 mol) of sDCDPS, 279.315 g (1.500 mol) of BP and 248.778 (1.80 mol) of potassium carbonate having a volume average particle size of 32.6 μm were suspended in 938 ml of NMP in a nitrogen atmosphere.

[0283] The mixture was heated to 190° C. within one hour. In the following, the reaction time is understood to be the time during which the reaction mixture was kept at 190° C. The water formed in the reaction was removed continuously by distillation, and the losses in NMP were replaced.

[0284] After a reaction time of 5 hours, the reaction was stopped by adding 1312 ml of NMP and cooling to room temperature (within one hour). The potassium fluoride formed in the reaction was removed by filtration. The polymer solution obtained 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 h. The beads were then dried at 120° C. for 24 h under reduced pressure (<100 mbar).

[0285] Table 2 :

[0286] C7 C8 C9 10 11 C12 Condensation time [h] 8 6,5 8 5.7 5.4 5 VN[ml / g] 45.1 69.6 52.1 86.1 92.3 74.0 sDCDPS content in sP [mol %] 30.2 33.0 31.3 33.2 33.4 33.6 <![CDATA[mol K + / mol Na + > 1 / 7 1 / 3 1 / 6 3.1 / 1 3.3 / 1 1 / 13

[0287] Characterization of thin films

[0288] The sulfonated polyarylene sulfone polymers (sP) from comparative examples C9 and C12 and inventive examples 10 and 11 were dissolved in NMP (20% by weight) and the solution was knife coated on a glass support with a thickness of 300 μm. The wet film was first dried in a vacuum at room temperature and then the temperature was raised to 140° C. for 12 h. The obtained films (FC9; F10; F11 and FC12) were then separated from the glass plate and extracted with hot water (85° C.) for 4 h and then dried again in a vacuum oven. The NMP content of the film was confirmed to be less than 0.1% by weight by H-NMR. Two films each having a weight of 0.1 g were then stored in deionized water until the water absorption no longer changed and the water content of the film (in %) was determined by gravimetric analysis.

[0289] film FC9 F10 F11 FC12 Water absorption [wt%] 27 16 15 29

[0290] Surprisingly, films containing higher potassium counterion contents showed less water swelling and better dimensional stability, which is advantageous for technological applications.

Claims

1. A method for preparing a sulfonated polyarylene sulfone polymer (sP), the method comprising the following steps: i) making the reaction mixture (R G ) conversion, the reaction mixture comprising: X moles of an aromatic dihalogen sulfone component (component A)), the aromatic dihalogen sulfone component comprising: G ) is based on the total molar amount of the aromatic dihalogen sulfone component (component A)) in: X 1 mol % of at least one sulfonated aromatic dihalogen sulfone (component (A1)), and X 2 mol % of at least one non-sulfonated aromatic dihalogen sulfone (component (A2)), Where X 1 In the range of 25 to 70, and X 2 In the range of 30 to 75, Y moles of at least one aromatic dihydroxy compound (component (B)), Z moles of at least one carbonate compound (component (C)), in The ratio of X to Y is in the range of 0.95 to 1.05, And among them Z is in the range of P to Q, Where P is calculated according to the following formula: P=Y*(1.05+X 1 / 100*1.05), And where Q is calculated according to the following formula: Q=Y*(1.05+X 1 / 100*1.4)。 2. The method according to claim 1, wherein the reaction mixture (R G )) further comprises at least one aprotic polar solvent (component (D)).

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

4. The method according to any one of claims 1 to 3, wherein based on the reaction mixture (R G ) in the present invention, component (A2) contains not less than 80 wt % of at least one aromatic dihalogen sulfone selected from the group consisting of 4,4'-dichlorodiphenyl sulfone and 4,4'-difluorodiphenyl sulfone, based on the total weight of component (A2) in the present invention.

5. The method according to any one of claims 1 to 4, wherein based on the reaction mixture (R G ) in the total weight of component (B), component (B) contains not less than 80 wt% of 4,4'-dihydroxybiphenyl.

6. Sulfonated polyarylene sulfone polymer (sP) obtainable by the process according to any one of claims 1 to 5.

7. The sulfonated polyarylene sulfone polymer (sP) according to claim 6, wherein the sulfonated polyarylene sulfone polymer (sP) comprises repeating units of the general formula (I): in t and q: each independently 0, 1, 2 or 3, Q 1 , T and Y 1 : Each independently is a chemical bond or is selected from -O-, -S-, -SO2-, -S(=O)-, -C(=O)-, -N=N- and -CR a R b -, Where R a and R b are independently a hydrogen atom or a C1-C 12 -alkyl, C1-C 12 -alkoxy or C6-C 18 -aryl group, and wherein at least one of Q, T and Y is -SO2-, Ar and Ar 1 : Each independently is C6-C 18 Aryl, wherein the C6-C 18 The aryl group is unsubstituted or substituted by at least one substituent selected from the group consisting of: C1-C 12 Alkyl, C1-C 12 Alkoxy, C6-C 18 Aryl, halogen and -SO-3X, p, m, n and k: each independently 0, 1, 2, 3 or 4, provided that the sum of p, m, n and k is not less than 1, and X 3 : is hydrogen or a cation equivalent.

8. The sulfonated polyarylene sulfone polymer (sP) according to claim 6 or 7, wherein the sulfonated polyarylene sulfone polymer contains repeating units, wherein the repeating units contain at least one -SO3X 3a group and / or at least one -SO3X 3b Group, Where X 3a and X 3b Each independently of the other is at least one selected from the group consisting of: hydrogen and a cation equivalent, wherein the X contained in the sulfonated polyarylene sulfone polymer (sP) 3a and X 3b At least 50 mol % of the total amount is potassium cations.

9. A sulfonated polyarylene sulfone polymer (sP), the sulfonated polyarylene sulfone polymer comprising repeating units, the repeating units comprising at least one -SO3X 3a group and / or at least one -SO3X 3b Group, where X 3a and X 3b Each independently of the other is at least one selected from the group consisting of: hydrogen and a cation equivalent, wherein the X contained in the sulfonated polyarylene sulfone polymer (sP) 3a and X 3b At least 50 mol % of the total amount is potassium cations.

10. Use of the sulfonated polyarylene sulfone polymer (sP) according to any one of claims 6 to 9 for the preparation of a membrane (M).

11. A method for preparing a membrane (M) comprising a sulfonated polyarylene sulfone polymer (sP) according to any one of claims 6 to 9, the method comprising the following steps: i) providing a solution (S) comprising a sulfonated polyarylene sulfone polymer (sP) according to any one of claims 6 to 9 and at least one solvent, ii) separating said at least one solvent from said solution (S) to obtain said membrane (M).

12. Membrane (M) obtainable by the process according to claim 11.

13. Membrane (M) comprising the sulfonated polyarylene sulfone polymer (sP) according to any one of claims 6 to 9.

14. Use of a membrane (M) according to claim 12 or 13 for separating gases from a gas mixture.

15. Use of the membrane (M) according to claim 12 or 13 in electrolyzers, electrodialysis cells and fuel cells.

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