Ion-conductive polymer and method for preparing same

Abstract

The present invention provides an ion-conductive polymer and a method for preparing same, wherein the ion-conductive polymer exhibits excellent ionic conductivity along with appropriate WU and low swelling and thus is useful as an ion-exchange material for an anion exchange membrane, ion-conductive membrane, electrolyte membrane, separator membrane, water treatment membrane, etc.

Description

Ion-conducting polymer and method for manufacturing the same

[0001] Cross-citation with related application(s)

[0002] This application claims the benefit of priority based on Korean Patent Application No. 10-2024-0131684 dated September 27, 2024, and all contents disclosed in the document of said Korean patent application are incorporated herein as part of this specification.

[0003] The present invention relates to an ion-conducting polymer that is useful as an ion exchange material such as an anion exchange membrane, ion-conducting membrane, electrolyte membrane, separation membrane, or water treatment membrane, by exhibiting excellent ion conductivity along with appropriate water content (WU) and low swelling degree, and a method for manufacturing the same.

[0004] Ion-conducting polymers are widely used as ion exchange materials, such as anion exchange membranes, ion-conducting membranes, electrolyte membranes, separators, or water treatment membranes, in various electrochemical devices such as fuel cells or water electrolysis.

[0005] As the problem of climate change caused by global warming has recently become serious, attention is focusing on research into alternative energy sources to reduce greenhouse gas emissions. Among these, fuel cells are pollution-free systems that utilize the energy from the chemical reaction between hydrogen and oxygen. With high power density and energy conversion efficiency, as well as the potential for miniaturization, they have a wide range of applications, including portable power sources for mobile communication equipment, transportation power sources for automobiles, and power generation systems for homes and the military.

[0006] Water electrolysis technology is a technology that produces hydrogen by electrolyzing water, and is classified into alkaline water electrolysis (AWE), proton exchange membrane water electrolysis (PEMWE), and anion exchange membrane water electrolysis (AEMWE) depending on the characteristics of the electrolyte and the type of membrane.

[0007] An anion exchange membrane water electrolysis system includes an anion exchange membrane (AEM) to prevent crossover between ion redox active species of the anode and cathode, and an ion-conducting polymer is mainly used when forming the anion exchange membrane.

[0008] Generally, ion-conducting polymers used to form anion exchange membranes consist of a polymer backbone and an ion-conducting group. Quaternary ammoniums such as benzyl ammonium, alkyl ammonium, imidazolium, piperidinium, and spiroammonium are used as ion-conducting groups, and poly(aryl ether sulfone) (PES), poly(aryl ether ketone) (PAEK), poly(phenylene oxide) (PPO), polyspirobisindane, polyphenylene (PP), and styrene-ethylene-butylene-styrene copolymer (SEBS) are used as polymer main chains constituting AEMs. In particular, the polyphenylene polymer main chain with an aryl ether-free structure contains hydroxide ions (OH - Due to its excellent chemical stability and mechanical properties, much research has recently been conducted on it.

[0009] Generally, in the ion conduction mechanism of AEM, water is OH - Since it acts as a conductive medium, appropriate water uptake (WU) is required for the high ionic conductivity of AEM. In addition, if AEM has a high hydration number, OH - It can reduce the ion conductivity of.

[0010] Polyphenylene-based AEMs possess a relatively low WU, or low hydration number, compared to their high ion exchange capacity (IEC). Therefore, polyphenylene-based AEMs have sought to achieve the necessary levels of WU and ion conductivity by introducing more ion conductors. Positively charged ion conductors have OH groups relative to the polymer backbone. - Its stability is relatively lower. Also, the introduction of excessive ion conductors causes a high WU, which leads to a reduction in ion conductivity and means that it may have a somewhat negative effect on the long-term stability of the AEM.

[0011] The present invention aims to provide an ion-conducting polymer that exhibits excellent ion conductivity along with appropriate WU and low swelling degree, and is useful as an ion exchange material such as anion exchange membrane, ion-conducting membrane, electrolyte membrane, separation membrane, or water treatment membrane, and a method for manufacturing the same.

[0012] The present invention also aims to provide an ion-conducting membrane prepared from the ion-conducting polymer.

[0013] To solve the above-mentioned problem, according to the present invention, an ion-conducting polymer comprising repeating units represented by the following chemical formulas 1 to 4 is provided:

[0014] [Chemical Formula 1]

[0015]

[0016] [Chemical Formula 2]

[0017]

[0018] [Chemical Formula 3]

[0019]

[0020] [Chemical Formula 4]

[0021]

[0022] In the above chemical formulas 1 to 4,

[0023] mQUP is a substituted or unsubstituted m-quaterphenylene, and

[0024] pQUP is a substituted or unsubstituted p-quaterphenylene, and

[0025] R a and R c Each is independently represented by the following chemical formula 5, and

[0026] R b and R d Each is independently represented by the following chemical formula 6, and

[0027] p, q, r, and s are each independently greater than or equal to 0, provided that p, q, r, and s are not simultaneously zero integers, and

[0028] If r is an integer greater than or equal to 1, at least one of p, q, and s is not 0, and

[0029] [Chemical Formula 5]

[0030]

[0031] [Chemical Formula 6]

[0032]

[0033] In the above chemical formulas 5 and 6,

[0034] R 1 , R 2 and R 3 Each is an independently substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, and

[0035] R 11 to R 13 , and R 21 to R 25 Each is independently a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or two adjacent groups are connected to each other to form an N-containing heterocyclic structure, and

[0036] Y1, Y2, and Y3 are each independently anions, and

[0037] * indicates the connection position.

[0038] In addition, according to the present invention, a method for manufacturing an ion-conducting polymer is provided, comprising: a first step of preparing a polymer precursor having a halogen pendant group by reacting one or more of m-quaterphenyl and p-quaterphenyl with a compound represented by the following chemical formula 8 in the presence of a strong acid; a second step of preparing a polymer precursor having a cationic pendant group by reacting the polymer precursor having the halogen pendant group with one or more of a compound represented by the following chemical formula 9 and a tertiary amine; and a third step of changing the counter ion by reacting the polymer precursor having the cationic pendant group or a membrane of the polymer precursor containing the same with a basic ion aqueous solution or an acidic ion aqueous solution.

[0039] [Chemical Formula 8]

[0040]

[0041] In the above chemical formula 8,

[0042] X is a halogen group, and

[0043] p is an integer from 1 to 10, and

[0044] [Chemical Formula 9]

[0045]

[0046] In the above chemical formula 9,

[0047] R 31 to R 33 Each is independently a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or two adjacent groups are connected to each other to form an N-containing heterocyclic structure, and

[0048] R34 and R 35 Each is independently a hydrogen or methyl group, and

[0049] R 4 is a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, and

[0050] X is a halogen.

[0051] In addition, according to the present invention, an ion-conducting membrane comprising the ion-conducting polymer is provided.

[0052] The ion-conducting polymer according to the present invention can exhibit excellent ion conductivity by facilitating the formation of ion channels for ion transport, and can also exhibit an appropriate WU and a low swelling ratio. Furthermore, the ion-conducting polymer has excellent solubility relative to its relatively high molecular weight, which enables the preparation of high-concentration polymer solutions and, as a result, exhibits excellent membrane processing properties. Accordingly, the ion-conducting polymer can be used as various ion exchange materials, such as ion-conducting membranes, electrolyte membranes, separators, water treatment membranes, or ionomers for membrane-electrode assemblies (MEAs).

[0053] Figure 1 is for the m-quaterphenyl (mQUP) prepared in Synthesis Example 1. 1 This is an H-NMR analysis graph.

[0054] FIG. 2 is for the brominated m-quaterphenyl (mQUP-Br) prepared in Step 1 of Example 1. 1 This is an H-NMR analysis graph.

[0055] FIG. 3 is for the polymer ((mQUP-N2(47)-co-N1(53))) prepared in step 2 of Example 1 1 This is an H-NMR analysis graph.

[0056] The terms used herein are merely for describing exemplary embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this specification, terms such as “comprising,” “comprising,” or “having” are intended to indicate the presence of the implemented features, steps, components, or combinations thereof, and should be understood as not precluding the existence or addition of one or more other features, steps, components, or combinations thereof.

[0057] The present invention is capable of various modifications and may take various forms, and specific embodiments are illustrated and described in detail below. However, this is not intended to limit the invention to the specific disclosed forms, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0058] In the present invention, "pendant" refers to a functional group attached to a side chain that is not an element constituting the main chain skeleton.

[0059] In addition, in the present invention, the term “substituted or unsubstituted” means that it is substituted or unsubstituted with one or more substituents selected from the group consisting of deuterium; halogen group; nitrile group; nitro group; hydroxyl group; carbonyl group; ester group; imide group; amino group; phosphine oxide group; alkoxy group; aryloxy group; alkyl thioxy group; aryl thioxy group; alkyl sulfoxy group; aryl sulfoxy group; silyl group; boron group; alkyl group; cycloalkyl group; alkenyl group; aryl group; aralkyl group; aralkenyl group; alkylaryl group; alkylamino group; aralkylamino group; heteroarylamino group; arylamino group; arylphosphine group; or heterocyclic groups comprising one or more of N, O, and S atoms, or is substituted or unsubstituted with a substituent in which two or more of the exemplified substituents are connected. For example, “a substituent in which two or more substituents are connected” may be a biphenyl group. That is, the biphenyl group can be an aryl group, or it can be interpreted as a substituent in which two phenyl groups are connected.

[0060] The present invention will be described in detail below.

[0061]

[0062] Specifically, the ion-conducting polymer according to the present invention is a compound comprising repeating units represented by the following chemical formulas 1 to 4:

[0063] [Chemical Formula 1]

[0064]

[0065] [Chemical Formula 2]

[0066]

[0067] [Chemical Formula 3]

[0068]

[0069] [Chemical Formula 4]

[0070]

[0071] In the above chemical formulas 1 to 4,

[0072] mQUP is a substituted or unsubstituted m-quaterphenylene, and

[0073] pQUP is a substituted or unsubstituted p-quaterphenylene, and

[0074] R a and R c Each is independently represented by the following chemical formula 5, and

[0075] R b and R d Each is independently represented by the following chemical formula 6, and

[0076] p, q, r, and s are each independently greater than or equal to 0, provided that p, q, r, and s are not simultaneously zero integers, and

[0077] If r is an integer greater than or equal to 1, at least one of p, q, and s is not 0, and

[0078] [Chemical Formula 5]

[0079]

[0080] [Chemical Formula 6]

[0081]

[0082] In the above chemical formulas 5 and 6,

[0083] R 1 , R 2 and R 3 Each is an independently substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, and

[0084] R 11 to R 13 , and R 21 to R 25 Each is independently a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or two adjacent groups are connected to each other to form an N-containing heterocyclic structure, and

[0085] Y1, Y2, and Y3 are each independently anions, and

[0086] * indicates the connection position.

[0087] The above-mentioned ion-conducting polymer may be a homopolymer comprising any one of the repeating units represented by the above chemical formulas 1 to 4.

[0088] In addition, the ion-conducting polymer may be a copolymer comprising two or more repeating units having different structures among the repeating units represented by Chemical Formulas 1 to 4. In this case, the copolymer may be a random copolymer.

[0089]

[0090] Conventional ion-conducting polymers have the advantage of being usable at high temperatures due to their high chemical stability and robust properties, as the polymer backbone is composed solely of phenyl or benzene units. However, because they have a structure in which multiple phenyl groups are linearly bonded, such as biphenyl and terphenyl, water uptake (WU) increases at high temperatures, which leads to a relative decrease in ion conductivity. Additionally, there is a problem of reduced solubility when the molecular weight is high.

[0091] In this regard, the ion-conducting polymer according to the present invention comprises one or more quaternyls among m-quaternyl and p-quaternyl, and has a structure in which one or two of a quaternary ammonium-based single cation group represented by Chemical Formula 5 and a multi-cation group represented by Chemical Formula 6 are mixed as cationic functional groups. Accordingly, it is easy to form ion channels for ion transfer, thereby exhibiting excellent ion conductivity, and can also exhibit an appropriate WU and a low swelling ratio. Furthermore, the ion-conducting polymer has excellent solubility relative to its relatively high molecular weight, enabling the preparation of high-concentration polymer solutions, and as a result, can exhibit excellent film-forming processability.

[0092] In particular, in the case of an ion-conducting polymer containing m-quaternphenyl, the twisting of the main chain structure within the molecule is strong, and by including multiple cationic groups with alkyl chain spacers in a ratio of about 50%, the distance between cations is sufficient, so it can exhibit improved dimensional stability while maintaining excellent solubility.

[0093] Accordingly, the above ion-conducting polymer can be used as various ion exchange materials, such as ion-conducting membranes, electrolyte membranes, separators, water treatment membranes, or ionomers for membrane-electrode assemblies (MEAs).

[0094] Specifically, in the above chemical formulas 1 to 4, mQUP is represented by the following chemical formula 7-1, and pQUP is represented by the following chemical formula 7-2:

[0095]

[0096] In the above chemical formulas 7-1 and 7-2, * indicates a bonding position.

[0097] Specifically, in the above chemical formulas 1 to 4, R a and R c Each is independently represented by the above chemical formula 5, and R b and R d Each is independently represented by the above chemical formula 6, and

[0098] At this time, in the above chemical formulas 5 and 6, R 1 , R 2 and R 3 Each may be an independently unsubstituted alkylene group having 1 to 12 carbon atoms, or 1 to 6 carbon atoms, or 4 to 6 carbon atoms, or 5 or 6 carbon atoms. More specifically, R 1 , R 2 and R 3 Each can be independently a pentylene group or a hexylene group.

[0099] Also, in the above chemical formulas 5 and 6, R 11 to R 13 , and R21 to R 25 Each can independently be a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms, or two adjacent groups can be connected to each other to form an N-containing heterocyclic structure.

[0100] More specifically, in the above chemical formulas 5 and 6, R 11 to R 13 , and R 23 to R 25 Each is independently a methyl group, an ethyl group, or a phenyl group, or two adjacent groups are connected to each other as R 11 to R 13 , or R 23 to R 25 It can form a piperidine structure together with this bonded nitrogen atom.

[0101] Also, in the above chemical formulas 5 and 6, R 21 and R 22 Each is independently a methyl group, an ethyl group, or a phenyl group, or is connected to each other as R 21 and R 22 It can form a piperidine structure with bonded nitrogen atoms.

[0102] Also, in the above chemical formulas 5 and 6, Y1, Y2, and Y3 are each independently chloride ion, bromide ion, iodide ion, and hydroxide ion (OH). - ), bicarbonate ion (HCO3 - ), dihydrogen phosphate ion (H2PO4 - ), hydrogen phosphate ion (HPO4 2- ) or phosphate ion (PO4 3- It can be.

[0103] Also, in the above chemical formula 6, Y2 and Y3 are identical or different from each other.

[0104]

[0105] More specifically, in the above chemical formulas 1 to 4, R a and R c Each can be independently any one of the following.

[0106]

[0107] In the above equation, Y1 is as previously defined.

[0108] More specifically, in the above chemical formulas 1 to 4, R b and R d Each can be independently any one of the following.

[0109]

[0110] In the above equation, Y2 and Y3 are as previously defined.

[0111] In addition, in the above chemical formulas 1 to 4, p, q, r, and s each represent the molar ratio of a polymer monomer (repeating unit).

[0112] Specifically, p, q, r, and s are each independently integers greater than or equal to 0, but p, q, r, and s are not simultaneously integers greater than or equal to 0. For example, if p, q, r, and s are each integers greater than or equal to 1, it means that the compound contains all repeating units represented by Chemical Formulas 1 to 4. For example, if p is an integer greater than or equal to 0, it means that the compound does not contain the repeating unit represented by Chemical Formula 1. For example, if p and r are integers greater than or equal to 0 and q and s are each integers greater than or equal to 1, it means that the compound contains only the repeating units represented by Chemical Formulas 2 and 4. More specifically, p, q, r, and s are each independently greater than or equal to 10, or greater than or equal to 20, or greater than or equal to 30, or greater than or equal to 40, or greater than or equal to 45, and less than or equal to 80, or less than or equal to 70, or less than or equal to 60, and p+q+r+s=100.

[0113] Meanwhile, if r is an integer greater than or equal to 1, at least one of p, q, and s is not 0. That is, the ion-conducting polymer includes a repeating unit represented by Chemical Formula 3, and necessarily includes at least one of the repeating units represented by Chemical Formulas 1, 2, and 4.

[0114] Specifically, the ion-conducting polymer may be a compound represented by any one of the following chemical formulas 1a to 1g, but is not limited thereto:

[0115] [Chemical Formula 1a]

[0116]

[0117] [Chemical Formula 1b]

[0118]

[0119] [Chemical Formula 1c]

[0120]

[0121] [Chemical Formula 1d]

[0122]

[0123] [Chemical Formula 1e]

[0124]

[0125] [Chemical Formula 1f]

[0126]

[0127] [Chemical formula 1g]

[0128]

[0129] In the above chemical formulas 1a to 1g, Y1, Y2, Y3, p, q, r, and s are as previously defined.

[0130] More specifically, in the above formula 1a, p and q are each independently an integer greater than or equal to 1, or greater than or equal to 10, or greater than or equal to 20, or greater than or equal to 30, or greater than or equal to 40, or greater than or equal to 45, and may be less than or equal to 80, or less than or equal to 70, or less than or equal to 60, and p+q=100.

[0131] Also, in the above chemical formula 1b, r and s are each independently an integer of 1 or more, or 10 or more, or 20 or more, or 30 or more, or 40 or more, or 45 or more, and may be 80 or less, or 70 or less, or 60 or less, and r+s=100.

[0132] Also, in the above chemical formula 1c, p, q, r and s are each independently an integer greater than or equal to 1, or greater than or equal to 10, or greater than or equal to 20, or greater than or equal to 30, or greater than or equal to 40, or greater than or equal to 45, and may be less than or equal to 80, or less than or equal to 70, or less than or equal to 60, and p+q+r+s=100.

[0133] Also, in the above chemical formula 1d, q may be an integer of 1 or more, or 10 or more, or 20 or more, or 30 or more, or 40 or more, or 45 or more, and may be an integer of 100 or less, or 80 or less, or 70 or less, or 60 or less.

[0134] Also, in the above chemical formula 1e, s may be an integer of 1 or more, or 10 or more, or 20 or more, or 30 or more, or 40 or more, or 45 or more, and may be an integer of 100 or less, or 80 or less, or 70 or less, or 60 or less.

[0135] Also, in the above chemical formula 1f, p and r are each independently an integer of 1 or more, or 10 or more, or 20 or more, or 30 or more, or 40 or more, or 45 or more, and may be 80 or less, or 70 or less, or 60 or less, and p+r=100.

[0136] Also, in the above chemical formula 1g, q and s are each independently an integer greater than or equal to 1, or greater than or equal to 10, or greater than or equal to 20, or greater than or equal to 30, or greater than or equal to 40, or greater than or equal to 45, and may be less than or equal to 80, or less than or equal to 70, or less than or equal to 60, and q+s=100.

[0137]

[0138] The ion-conducting polymer having the above-described structure may have a weight-average molecular weight (Mw) of 30 to 500 kDa. More specifically, it may have an Mw of 80 to 400 kDa. If the Mw is excessively low, for example, less than 30 kDa, film formation becomes difficult, the moisture content increases, and it decomposes easily under attack by radicals, which may reduce ion conductivity and durability. On the other hand, if the Mw is excessively high, for example, if the weight-average molecular weight (Mw) exceeds 500 kDa, the rapidly increased viscosity makes it difficult to prepare the polymer solution and form it into a film, which may make the film manufacturing process impossible.

[0139] Meanwhile, the ion-conducting polymer represented by the above chemical formula 1 is, for example,

[0140] A first step of preparing a polymer precursor having a halogen pendant group by reacting one or more of m-quaterphenyl and p-quaterphenyl with a compound represented by the following chemical formula 8 in the presence of a strong acid;

[0141] A second step of preparing a polymer precursor having a cationic pendant group by reacting the polymer precursor having the above halogen pendant group with one or more of a compound represented by the following chemical formula 9 and a tertiary amine;

[0142] A third step of reacting the polymer precursor having the above-mentioned cation pendant group or a membrane of the polymer precursor containing the same with a basic ion aqueous solution or an acidic ion aqueous solution to change the counter ion; can be manufactured by a manufacturing method comprising:

[0143] [Chemical Formula 8]

[0144]

[0145] In the above chemical formula 8,

[0146] X is a halogen group, and

[0147] t is an integer from 1 to 10, and

[0148] [Chemical Formula 9]

[0149]

[0150] In the above chemical formula 9,

[0151] R 31 to R 33 Each is independently a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or two adjacent groups are connected to each other to form an N-containing heterocyclic structure, and

[0152] R 34 and R 35 Each is independently a hydrogen or methyl group, and

[0153] R 4 is a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, and

[0154] X is a halogen.

[0155] Additionally, the above manufacturing method may further include a step prior to the first step of heating 3-iodobiphenyl or 4-iodobiphenyl to 120 to 150°C in the presence of a palladium catalyst and an alkali metal carbonate to produce quaternphenyl, specifically m-quaternphenyl or p-quaternphenyl.

[0156]

[0157] Each step is explained below.

[0158] (Stage 1)

[0159] The first step is to prepare a polymer precursor having a halogen pendant group from one or more of the quarterphenyls among m-quaternphenyl and p-quaternphenyl.

[0160] Specifically, the first step can be performed by dissolving one or more of the quadrphenyls among m-quaternphenyl and p-quaternphenyl and the compound represented by the chemical formula 8 in a halogenated hydrocarbon solvent under a nitrogen atmosphere, and then adding a strong acid to react them.

[0161] The compound represented by the above chemical formula 8 may specifically be a trifluoroalkyl ketone such as 7-bromo-1,1,1-trifluoroheptan-2-one, 8-bromo-1,1,1-trifluorooctan-2-one, or 9-bromo-1,1,1-trifluorononan-2-one, and any one or a mixture of two or more of the above compounds may be used.

[0162] The molecular weight of the main chain in Chemical Formulas 1 to 4 is determined according to the amount of compound represented by Chemical Formula 8 and the amount of catalytic strong acid added. For example, the compound represented by Chemical Formula 8 may be added in a molar ratio of 1 to 3 or 1 to 1.5 molar ratio per mole of quarterphenyl.

[0163] In addition, depending on the type of compound represented by Chemical Formula 8, the length of the cationic functional group increases or decreases, so R a to R d is determined. Therefore, it is desirable to appropriately select the type of compound represented by Chemical Formula 8 while considering the length of the cationic functional group. For example, regarding the length of the cationic functional group, specifically in Chemical Formulas 5 and 6 above, R 1 , R 2 and R 3 Stability is excellent when each of these is independently an alkylene group having 5 or 6 carbon atoms.

[0164] Meanwhile, m-quaternphenyl, p-quaternphenyl, or a mixture thereof may be used as the quaternphenyl for preparing the ion-conducting polymer according to the present invention. These compounds may be commercially available or may be prepared directly. In the case of direct preparation, for example, m-quaternphenyl can be prepared by heating 3-iodobiphenyl to 120 to 150°C in the presence of a palladium catalyst and an alkali metal carbonate. Specific preparation methods will be described in detail in the synthesis examples below.

[0165] As a solvent for dissolving the above-mentioned quadrphenyl and the compound represented by Chemical Formula 8, a halogenated hydrocarbon solvent may be used, and more specifically, an aliphatic halogenated hydrocarbon such as dichloromethane, dichloroethane, chloroform, and carbon tetrachloride may be used.

[0166] In addition, the dissolution process for the above solvent can be performed at 0 to 10°C.

[0167] After dissolution is complete, a strong acid is added dropwise to the resulting solution and mixed.

[0168] The above strong acid acts as a catalyst and serves as a reaction initiator. Specific examples of the above strong acid include trifluoromethanesulfonic acid, trifluoroacetic acid, toluenesulfonic acid, or methanesulfonic acid, and any one or more of these may be used.

[0169] In addition, the above strong acid may be used in a molar ratio of 1 to 15, more specifically 6 to 10, based on 1 mole of quarterphenyl.

[0170] After mixing the strong acid, a process of raising the resulting reaction mixture from 0°C to room temperature and stirring for 10 to 20 hours may be further performed.

[0171] As a result of the above process, a polymer precursor having a halogen pendant group is produced in the reaction product.

[0172] Accordingly, the reaction product can be dropped into an alcohol such as methanol to precipitate a polymer precursor having the halogen pendant group, thereby obtaining it in a solid state.

[0173] Additionally, the polymer precursor can be obtained with high purity by performing conventional separation and purification processes such as washing, separation, and drying.

[0174]

[0175] (Stage 2)

[0176] The second step is to react the polymer precursor having a halogen pendant group prepared in the first step with one or more of a compound represented by the following chemical formula 9 and a tertiary amine to prepare a polymer precursor having a cationic pendant group.

[0177] Specifically, this can be carried out by reacting the polymer precursor having the halogen pendant group with the compound represented by the chemical formula 9 or a tertiary amine; or by reacting the polymer precursor having the halogen pendant group with the compound represented by the chemical formula 9 and then reacting it with a tertiary amine.

[0178] The compound represented by the above chemical formula 9 and the tertiary amine are nucleophiles that provide a cation group, and through the above reaction, the halogen group in the precursor is substituted with the cation group of the nucleophile, and as a result, a polymer precursor having a cationic pendant group is prepared.

[0179] Specifically, the compound represented by the above chemical formula 9 contains both a tertiary ammonium group and a quaternary ammonium group. Specific examples include N-(dimethylaminohexyl)-N,N,N-trimethylammonium iodide, 6-(dimethylaminohexyl)-1-methylpiperidinium iodide, or 1,1-dimethyl-4-(3-(1-methylpiperidin-4-yl)propyl)piperidin-1-ium iodide, and any one or more of these may be used.

[0180] The above ammonium halide salt can be added in a molar ratio of 0.1 to 1.5 per 1 mole of a polymer precursor having a halogen pendant group.

[0181] In addition, the above tertiary amine may include trialkylamine, 1-alkylpiperidine, 1-alkylpyrrolidine, etc., and these may be unsubstituted or substituted with one or more alkyl groups. Specific examples of the above tertiary amine may include trimethylamine, triethylamine, tripropylamine, 1-methylpiperidine, 1-methylpyrrolidine, or 1,2,2,6,6-pentamethylpiperidine, etc., and any one of these or a mixture of two or more may be used.

[0182] The above tertiary amine can be added in a molar ratio of 1 to 5 per 1 mole of a polymer precursor having a halogen pendant group.

[0183] In addition, when reacting the compound represented by Chemical Formula 9 with a tertiary amine, either one of these compounds may be used, or both may be used. Also, when both the compound represented by Chemical Formula 9 and the tertiary amine are used, they may be added simultaneously or sequentially. In addition, when adding sequentially, the order of addition is not particularly limited. For example, the tertiary amine may be added after the compound represented by Chemical Formula 9. In this case, a portion of the halogen groups in the precursor is first substituted with cationic functional groups by the compound represented by Chemical Formula 9, and the remaining halogen groups in the precursor are subsequently substituted with cationic functional groups by the tertiary amine added thereafter.

[0184] The reaction in the second step above can be carried out at 60°C or lower.

[0185] In addition, for the reaction in the second step above, n-methyl pyrrolidone (NMP), N,N-dimethyl acetamide, dimethyl sulfoxide, or dimethyl formamide may be used as the polar aprotic solvent. The amount used is not particularly limited and can be appropriately selected considering the reaction efficiency, etc.

[0186]

[0187] (Stage 3)

[0188] Next, in the third step, the polymer precursor having the cation pendant group or the membrane of the polymer precursor containing it, prepared in the second step, is reacted with a basic ion aqueous solution or an acidic ion aqueous solution to change the counter ion.

[0189] The counterion in the polymer precursor having a cationic pendant group prepared in the second step above is Br - or I - It is a halogen ion such as . When a basic or acidic aqueous ion solution is added to this and reacted, the counter ion becomes OH - It changes to. For example, when using an aqueous potassium hydroxide solution as a basic ion solution, the counter ion of the cation pendant group is OH - It changes to.

[0190] For example, a polymer precursor having a cation pendant group prepared in the second step above can be dissolved in a solvent to prepare a polymer solution, and after forming a film using this, a basic ion aqueous solution or an acidic ion aqueous solution can be introduced into the prepared film and reacted to change the counter ion.

[0191] In addition, the change of the counter ion may be performed after applying the ion-conducting polymer to a device in the relevant field, depending on the application field of the ion-conducting polymer. For example, when the ion-conducting polymer is used as an anion exchange membrane in an anion exchange membrane water electrolysis system, a membrane may be manufactured using a polymer precursor having a cation pendant group prepared in the second step, and the manufactured membrane may be interposed between an oxidation electrode and a reduction electrode to manufacture a Membrane Electrode Assembly (MEA), and then the change of the counter ion may be performed by introducing a basic ion aqueous solution or an acidic ion aqueous solution during the cell performance evaluation step.

[0192] The above basic ion aqueous solution is hydroxide ions (OH - ), or bicarbonate ions (HCO3 - It includes a raw material for basic ions such as ). Specifically, the raw material for basic ions may be a strong base such as sodium hydroxide, potassium hydroxide, etc.; or a weak base such as sodium hydrogen carbonate, etc., and may include one or more of these.

[0193] The above basic ion aqueous solution may contain the above-mentioned basic ion raw material in an amount of 1.0 to 50.0 weight% based on the total weight of the aqueous solution.

[0194] In addition, the above acidic ion aqueous solution is dihydrogen phosphate ion (H2PO4) - ), hydrogen phosphate ion (HPO4 2- ) or phosphate ion (PO4 3-It includes raw materials for acidic ions such as ). Specifically, the raw materials for acidic ions may be phosphoric acid (H3PO4); polyphosphoric acid; or phosphates such as potassium dihydrogen phosphate, sodium dihydrogen phosphate, disodium hydrogen phosphate, sodium phosphate, etc., and may include one or more of these.

[0195] The above acidic ion aqueous solution may contain acidic ion raw material in an amount of 1.0 to 85 weight% based on the total weight of the aqueous solution.

[0196] The ion-conducting polymer produced by the above-described manufacturing method can exhibit excellent ion conductivity by facilitating the formation of ion channels for ion transport, and can also exhibit improved dimensional stability while maintaining excellent solubility. Furthermore, the ion-conducting polymer can exhibit improved film-forming processability due to its excellent solubility relative to its relatively high molecular weight. As a result, the ion-conducting polymer can be used as various ion exchange materials, such as ion-conducting single membranes, ion-conducting reinforced membranes, ion-conducting composite membranes, ion-conducting reinforced composite membranes, ion-conducting cross-linked membranes, electrolyte membranes, separators, water treatment membranes, or ionomers for membrane-electrode assemblies (MEAs), and is particularly useful for anion exchange membranes. Specifically, the ion-conducting polymer can be used as an ion exchange material in electrochemical systems such as water electrolysis systems, fuel cells, redox flow batteries, carbon dioxide reduction systems, electrochemical ammonia production and decomposition systems, electrodialysis (ED) systems, reverse electrodialysis (RED) systems, or capacitive deionization (CDI) systems.

[0197] Accordingly, according to another embodiment of the invention, an ion-conducting membrane comprising the ion-conducting polymer is provided.

[0198] The above-mentioned ion-conducting membrane can be manufactured by a conventional method for manufacturing ion-conducting membranes, except for using the above-mentioned ion-conducting polymer.

[0199] For example, a resin composition may be prepared by further including one or more of the above-mentioned ion-conducting polymer and, if necessary, various additives such as antioxidants, heat stabilizers, lubricants, tackifiers, plasticizers, crosslinking agents, defoaming agents, and dispersants, and the composition may be extruded and manufactured into a molded body in the form of a fiber or film by any method such as spinning, rolling, or casting.

[0200] More specifically, the above ion-conducting polymer and optionally one or more additives are dissolved in a solvent such as N-methylpyrrolidone, dimethylformamide, dimethyl sulfoxide, or dimethylacetamide to prepare a resin composition, the prepared composition is applied to a plate such as a glass plate or a support for film manufacturing and dried, and then a film with a thickness of several to several hundred μm, specifically 10 to 120 μm, is obtained, and then detached from the plate or support for film manufacturing to produce the product.

[0201] Since the above ion-conducting membrane contains the above-mentioned ion-conducting polymer, it can exhibit excellent ion conductivity along with a low WU and swelling ratio.

[0202] Specifically, the ion-conducting membrane has an ion exchange capacity (IEC) of 2.00 meq. / g or more, or 2.20 to 3.00 meq. / g, measured after doping with chloride counter ions in the form of 2 to 24 hours.

[0203] The method and conditions for measuring the ion exchange capacity of the above ion-conducting membrane are as described in the experimental examples below.

[0204] In addition, the above ion-conducting membrane has an in-plane ion conductivity of 70 mS / cm or more, more specifically 70 to 120 mS / cm, measured at 60°C using a 4-probe electrode after doping with a hydroxide counter ion for more than 24 hours.

[0205] In addition, the above ion-conducting membrane is doped with a hydroxide counter ion for more than 24 hours, immersed in a 1M KOH aqueous solution for more than 24 hours, dried at 80°C for more than 15 hours, and has a WU (Water Uptake) of 70 wt% or more, or 70 to 150 wt%, calculated according to the following mathematical formula 3.

[0206] [Mathematical Formula 3]

[0207] WU (wt%) = (W wet -W dry )Х100 / W dry

[0208] (In the above mathematical formula 3,

[0209] W wet is the weight of the anion exchange membrane measured after doping with the form of a hydroxide counter ion, immersing it in a 1M KOH aqueous solution for at least 24 hours, and

[0210] W dry The above W wet It is the weight of the anion exchange membrane measured after drying the measured anion exchange membrane in an 80℃ vacuum oven for at least 15 hours.

[0211] In addition, the above ion-conducting membrane is doped with a hydroxide counter ion for more than 24 hours, immersed in a 1M KOH aqueous solution for more than 24 hours, dried at 80°C for more than 15 hours, and has a swelling ratio calculated according to the following mathematical formula 4 that is 10% or more, or 10 to 50%.

[0212] [Mathematical Formula 4]

[0213] Swelling Ratio (%) = (L wet -L dry )Х100 / L dry

[0214] (In the above mathematical formula 4,

[0215] L wet is the length (mm) of an anion exchange membrane measured after doping with hydroxide counter ions and immersing in a 1M KOH aqueous solution for at least 24 hours, and

[0216] L dry The above L wet It is the length (mm) of the anion exchange membrane measured immediately after drying the measured anion exchange membrane in a vacuum oven at 60 to 80°C for at least 15 hours at room temperature.

[0217] In addition, according to the present invention, a water electrolysis system comprising an anion exchange membrane manufactured from the ion-conducting polymer is provided.

[0218] Specifically, the water electrolysis system may comprise the anion exchange membrane described above; a reduction electrode located on one side of the anion exchange membrane; and an oxidation electrode of the other embodiment located on the other side of the anion exchange membrane layer so as to bring a catalyst layer into contact with the anion exchange membrane. Specifically, the anion exchange membrane water electrolysis system according to one embodiment of the present invention may be an MEA.

[0219] This may result in improved water electrolysis performance by including the oxidation catalyst and oxidation electrode of the aforementioned embodiment. Other details can be implemented by referring to anion exchange membrane water electrolysis systems widely known in the art.

[0220]

[0221] Preferred embodiments are presented below to aid in understanding the present invention; however, the following embodiments are merely illustrative of the invention, and it is obvious to those skilled in the art that various changes and modifications are possible within the scope and spirit of the invention, and that such changes and modifications fall within the scope of the appended claims.

[0222] Meanwhile, unless otherwise specified in this specification, ordinary temperature means 20 to 25°C, and atmospheric pressure means 0.95 to 1.05 atm.

[0223] In addition, NMR analysis of the compounds prepared in the synthesis examples and examples was performed using a Bruker AVANCE III HD 600 MHz instrument (manufactured by Bruker) under conditions of room temperature and spin 20 Hz.

[0224] In addition, the molecular weight of the compound prepared in the synthesis example was the weight-average molecular weight (g / mol) and was measured through gel permeation chromatography analysis. Specifically, using an Agilent 1260 / Malvern TDA305 instrument (Agilent), measurements were performed under conditions of Column: PL gel 500Å+100Å+50Å (Agilent) and Standard: Polystyrene with various Mw values ​​according to molecular weight.

[0225] Sample preparation conditions (solvent): THF solvent used and filtered via 0.1 µm PTFE, sample concentration 2.0 mg / ml

[0226] Column Condition: Column TSKgel GMHxl

[0227] Solvent THF

[0228] Sample injection volume 200 µl

[0229] Flow rate 1.0 ml / min

[0230] Analysis temperature: Room temperature

[0231] Refractive index analysis

[0232]

[0233] Synthesis Example 1: Synthesis of m-quaternyl (mQUP)

[0234]

[0235] 3-Iodobiphenyl (3IBP, 10.45 g, 37.32 mmol, 1.0 equiv), Pd(OAc)2 (0.42 g, 1.866 mmol), K2CO3 (6.19 g, 44.78 mmol, 1.2 equiv), and PEG 4000 (20 g) were added to a 100 ml round-bottom flask and stirred at 120°C for 5 days. After confirming the reaction termination point based on TLC monitoring, organic matter was extracted using diethyl ether by washing the reaction mixture.

[0236] After removing a small amount of PEG 4000 from the extracted organic layer using water, diethyl ether was evaporated and removed using a rotary evaporator, and white solid m-quaterphenyl (mQUP) was obtained by recrystallization in hexane (yield: 4.36 g, yield: 76%).

[0237] Also, regarding the obtained mQUP 1 H-NMR analysis was performed, and the results are shown in Figure 1.

[0238]

[0239] Example 1: Synthesis of ion-conducting polymer (mQUP-N2(47)-co-N1(53))

[0240] Step 1

[0241]

[0242] m-Quaterphenyl (mQUP) (5.0 g, 16.318 mmol, 1.0 equiv) prepared in Synthesis Example 1 above and 7-bromo-1,1,1-trifluoroheptan-2-one (7BTFH, Synquest) (4.42 g, 17.950 mmol, 1.1 equiv) were placed in a 100 ml round-bottom flask, and a nitrogen atmosphere was established. 25 mL of anhydrous dichloromethane was added to the mixture, and the temperature of the reaction mixture was lowered to 0°C under a nitrogen atmosphere. Trifluoromethanesulfonic acid (TFSA, 11.5 mL, 130.544 mmol, 8.0 equiv) was added dropwise to the resulting reaction mixture, and the temperature of the reaction mixture was raised to room temperature and stirred while maintaining the nitrogen atmosphere. As the reaction proceeded, the viscosity of the reaction mixture increased, and after 15 hours, a dark brown gel-like reaction product was obtained.

[0243] 25 mL of dichloromethane was added to the obtained reaction product to dissolve it, and the resulting reaction product was added dropwise to 500 mL of methyl alcohol. The mixture was then stirred for 2 to 3 hours to allow for solvent exchange. After stopping the stirring and discarding the supernatant, 500 mL of fresh methyl alcohol was added to the resulting reaction product, and the mixture was washed while stirring again. The solids of the washed reaction product were separated and dried. 25 mL of tetrahydrofuran was added to the dried reaction product to dissolve it, and the resulting solution was added dropwise to 500 mL of methyl alcohol, followed by stirring for 2 to 3 hours. After stirring was complete, the solids were separated and dried under reduced pressure to obtain brominated m-quaterphenyl (mQUP-Br) as a precursor (Yield: 8.55 g, Yield: 98.2%).

[0244] Gel permeation chromatography analysis was performed on the obtained mQUP-Br. As a result, the number average molecular weight (Mn) was 31,260 Da, the weight average molecular weight (Mw) was 217,996 Da, and the molecular weight distribution (Mw / Mn) was 6.973.

[0245] Also, regarding the above mQUP-Br 1 H-NMR analysis was performed, and the results are shown in Figure 2.

[0246]

[0247] Step 2

[0248]

[0249] (In the above reaction equation, p is an integer of 53, and q is an integer of 47)

[0250] mQUP-Br (2.0 g, 3.735 mmol, 1.0 equiv) prepared in Step 1 above was placed in a 50 mL round-bottom flask and dissolved in N,N-dimethylacetamide (DMAc, 20 mL). 6-(Dimethylamino)-N,N,N-trimethyl-1-hexanaminium iodide (N2) (0.55 equiv) was added dropwise to the resulting solution and stirred at room temperature for 48 hours.

[0251] Trimethylamine (TMA) (1.78 mL, 7.470 mmol, 2.0 equiv) was added dropwise to the resulting solution and stirred at room temperature for 24 hours. Once the reaction was complete, the resulting reaction product was added dropwise to Acetone (200 mL) and stirred for 2 to 3 hours. After stirring was completed, the supernatant was discarded, and Hexane (200 mL) was added to the resulting product and washed with stirring. The solid precipitate of the washed product was separated and dried, and the solid was separated and dried under reduced pressure to obtain the ion-conducting polymer (mQUP-N2(47)-co-N1(53))(I) (Yield: 2.64 g, Yield: 96.3%).

[0252] Regarding the obtained ion-conducting polymer (mQUP-N2(47)-co-N1(53))(I) 1 H-NMR analysis was performed, and the results are shown in Figure 3.

[0253] 1 H-NMR: 1.20-1.40 (m), 1.59-1.72 (m), 2.53-2.64 (m), 3.02 (s), 3.06 (s), 3.18-3.33 (m), 7.37-7.50 (m, 4H), 7.54-7.65 (m, 2H), 7.70-7.77 (m, 2H), 7.78-7.84 (m, 2H), 7.85-7.96 (m, 4H), 7.98-8.12 (m, 2H)

[0254]

[0255] Example 2

[0256] Step 1

[0257]

[0258] Brominated p-quaterphenyl (pQUP-Br) was obtained by performing the same procedure as in Step 1 of Example 1, except that p-quaterphenyl (pQUP) (manufactured by TCI) was used instead of mQUP in Step 1 of Example 1 (amount obtained: 8.44 g, yield: 97%).

[0259] In addition, gel permeation chromatography analysis was performed on the obtained pQUP-Br, and the number average molecular weight (Mn) was 28,972 Da and the weight average molecular weight (Mw) was 125,742 Da.

[0260] 1 H-NMR: 1.22-1.35 (m, 2H), 1.45-1.50 (m, 2H), 1.80-1.90 (m, 2H), 2.40-2.52 (m, 2H), 3.30-3.40 (m, 2H), 7.30-7.42 (m, 4H), 7.60-7.70 (m, 4H), 7.70-7.82 (m, 8H)

[0261]

[0262] Step 2

[0263] An ion-conducting polymer (pQUP-N2(48)-co-N1(52))(II) having the following structure was synthesized by performing the same method as in Step 2 of Example 1, except that pQUP-Br prepared in Step 1 was used instead of mQUP-Br in Step 2 of Example 1 (Yield: 4.49 g, Yield: 96.1%).

[0264]

[0265] (In the above chemical formula II, r is an integer of 48, and s is an integer of 52)

[0266] 1H-NMR: 1.20-1.40 (m), 1.60-1.70 (m), 2.53-2.65 (m), 3.00 (s), 3.04 (s), 3.07 (s), 320-3.35 (m), 7.40-7.50 (m, 4H), 7.70-8.00 (m, 12H).

[0267]

[0268] Example 3

[0269] Except for changing the N2 reaction ratio in step 2 of Example 1 to 0.65 equiv, an ion-conducting polymer (mQUP-N2(52)-co-N1(48)) in which p is an integer of 48 and q is an integer of 52 in Formula I was synthesized (Yield: 2.71 g, Yield: 95.4%).

[0270] 1 H-NMR: 1.20-1.40 (m), 1.59-1.72 (m), 2.53-2.64 (m), 3.02 (s), 3.06 (s), 3.18-3.33 (m), 7.37-7.50 (m, 4H), 7,54-7.65 (m, 2H), 7.70-7.77 (m, 2H), 7.78-7.84 (m, 2H), 7.85-7.96 (m, 4H), 7.98-8.12 (m, 2H).

[0271]

[0272] Example 4

[0273] An ion-conducting polymer (mQUP-N2(50)-co-N1(50)) in which p is an integer of 50 and q is an integer of 50 in the above formula I was synthesized (yield: 1.10 g, yield: 99%) by performing the same method as in Example 1, except that in Step 2 of Example 1, an N2 reaction ratio of 0.60 equiv was added and stirred at room temperature for 24 hours, and TMA was added and stirred at room temperature for 48 hours.

[0274] 1H-NMR: 1.20-1.40 (m), 1.59-1.72 (m), 2.53-2.64 (m), 3.02 (s), 3.06 (s), 3.18-3.33 (m), 7.37-7.50 (m, 4H), 7,54-7.65 (m, 2H), 7.70-7.77 (m, 2H), 7.78-7.84 (m, 2H), 7.85-7.96 (m, 4H), 7.98-8.12 (m, 2H)

[0275]

[0276] Example 5

[0277] Except for changing the N2 reaction ratio in Step 2 of Example 1 to 0.60 equiv and the reaction time, i.e., the stirring time, to 24 hours, the same method as in Example 1 was performed to synthesize an ion-conducting polymer (mQUP-N2(42)-co-N1(58))) in which p is an integer of 58 and q is an integer of 42 in Formula I (Yield: 3.35 g, Yield: 96%).

[0278] 1 H-NMR: 1.20-1.40 (m), 1.59-1.72 (m), 2.53-2.64 (m), 3.02 (s), 3.06 (s), 3.18-3.33 (m), 7.37-7.50 (m, 4H), 7,54-7.65 (m, 2H), 7.70-7.77 (m, 2H), 7.78-7.84 (m, 2H), 7.85-7.96 (m, 4H), 7.98-8.12 (m, 2H)

[0279]

[0280] Example 6

[0281] Except for changing the N2 reaction ratio in Step 2 of Example 1 to 0.40 equiv and the reaction time to 24 hours, the same method as in Example 1 was used to synthesize an ion-conducting polymer (mQUP-N2(30)-co-N1(70)) in which p is an integer of 70 and q is an integer of 30 in Formula I (Yield: 3.14 g, Yield: 96.6%).

[0282] 1 H-NMR: 1.20-1.40 (m), 1.59-1.72 (m), 2.53-2.64 (m), 3.02 (s), 3.06 (s), 3.18-3.33 (m), 7.35-7.55 (m, 4H), 7.56-7.65 (m, 2H), 7.66-7.98 (m, 8H), 8.00-8.10 (m, 2H)

[0283]

[0284] Example 7

[0285]

[0286] mQUP-Br (0.5 g, 0.934 mmol, 1.0 equiv) prepared in Step 1 of Example 1 was placed in a 100 mL round-bottom flask and dissolved in N,N-dimethylacetamide (DMAc, 4 mL). 6-(Dimethylamino)-N,N,N-trimethyl-1-hexanaminium iodide (N2) (4.0 equiv) was added dropwise to the resulting solution and stirred at room temperature for 28 hours.

[0287] When the reaction was complete, the resulting reaction product was added dropwise to Acetone (100 mL) and stirred for 2 to 3 hours. After stirring was completed, the supernatant was discarded, and Hexane (100 mL) was added to the resulting product and washed with stirring. The solid precipitate of the washed product was separated and dried, and the solid was separated and dried under reduced pressure to obtain the ion-conducting polymer (mQUP-N2)(III) (Mw=196,449Da, yield: 0.753 g, yield: 94.8%).

[0288] 1 H-NMR: 1.20-1.40 (m), 1.59-1.72 (m), 2.53-2.64 (m), 3.02 (s), 3.06 (s), 3.18-3.33 (m), 7.37-7.50 (m, 4H), 7.54-7.65 (m, 2H), 7.70-7.77 (m, 2H), 7.78-7.84 (m, 2H), 7.85-7.96 (m, 4H), 7.98-8.12 (m, 2H)

[0289]

[0290] Comparative Example 1

[0291] An ion-conducting polymer (mTP-N2(47)-co-N1(53))(IV) having the following structure was synthesized by performing the same method as in Step 2 of Example 1, except that mTP-Br was used instead of mQUP-Br in Step 2 of Example 1 (Yield: 4.058 g, Yield: 95.5%).

[0292]

[0293] (In the above chemical formula IV, x is an integer of 53 and y is an integer of 47)

[0294]

[0295] Comparative Example 2

[0296] Step 1

[0297]

[0298] Brominated p-quaterphenyl (pQUP-Br) was obtained in the same manner as in Step 1 of Example 2 above (amount obtained: 8.44 g, yield: 97%).

[0299] In addition, gel permeation chromatography analysis was performed on the obtained pQUP-Br, and the number average molecular weight (Mn) was 28,972 Da / weight average molecular weight (Mw) was 125,742 Da.

[0300] 1 H-NMR: 1.22-1.35 (m, 2H), 1.45-1.50 (m, 2H), 1.80-1.90 (m, 2H), 2.40-2.52 (m, 2H), 3.30-3.40 (m, 2H), 7.30-7.42 (m, 4H), 7.60-7.70 (m, 4H), 7.70-7.82 (m, 8H)

[0301]

[0302] Step 2

[0303]

[0304] pQUP-Br (3.5 g, 6.495 mmol, 1.0 equiv) prepared in Step 1 was placed in a 100 mL round-bottom flask and dissolved in N,N-dimethylacetamide (DMAc, 4 mL). Trimethylamine (TMA) (3.8 mL, 24.68 mmol, 3.8 equiv) was added dropwise to the resulting solution and stirred overnight at room temperature. The resulting reaction mixture was added dropwise to ether (100 mL) and stirred for 2 to 3 hours. After stirring was completed, the supernatant was discarded, and 100 mL of acetone was added to the resulting product and washed with stirring. The solid precipitate of the washed product was separated and dried, and the solid was separated and dried under reduced pressure to obtain polyphenylene (p-QUP-N1) composed of repeating units represented by the chemical formula V (Mw=125,742 Da, yield: 2.69g, yield: 96%).

[0305] 1 H-NMR: 1.20-1.40 (m, 4H), 1.60-1.70 (m, 2H), 2.53-2.65 (m, 2H), 3.04 (s, 9H), 3.20-3.30 (m, 2H), 7.40-7.50 (m, 4H), 7.75-8.00 (m, 12H)

[0306]

[0307] Comparative Example 3

[0308] Except for changing pQUP to biphenyl in Step 1 of Comparative Example 2 above, the same method as Comparative Example 2 was performed to obtain an ion-conducting polymer (BP-N1)(VI) having the following structure (Mw: 113,336 Da, yield: 8.26 g, yield: 97.6%).

[0309]

[0310]

[0311] Comparative Example 4

[0312] Except for changing pQUP to m-terphenyl (mTP) in Step 1 of Comparative Example 2, the same method as in Comparative Example 2 was performed to obtain an ion-conducting polymer (mTP-N1) (VII) having the following structure (Mw=153,779 Da, yield: 4.27 g, yield: 97%).

[0313]

[0314]

[0315] Comparative Example 5

[0316] I used the FAA-3-50 manufactured by FUMATECH BWT GmbH.

[0317]

[0318] Comparative Example 6

[0319] I used the FAA-3-PK-75 manufactured by FUMATECH BWT GmbH.

[0320]

[0321] Experimental Example

[0322] (1-1) Weight-average molecular weight (Mw)

[0323] For the ion-conducting polymers prepared in the examples and comparative examples, the weight-average molecular weight was measured through gel permeation chromatography analysis. Based on the calibration curve formed using a polystyrene standard foam, Mw (g / mol) was derived from the analysis results. However, since GPC measurement is not possible for ionic polymers, GPC was measured for the Precursor Polymer before the Quaternization reaction.

[0324] <GPC 분석 조건>

[0325] Device used: Agilent

[0326] Columns: Agilent PL Mixed D, Agilent PLgel 100Å, Agilent PLgel 50Å

[0327] Sample concentration: 1 wt / vol% in tetrahydrofuran (THF)

[0328] Carrier: THF

[0329] Detection method: RI

[0330] Flow rate: 1.0 ml / min

[0331] Column temperature: 25℃

[0332] Detector: Agilent RI detector

[0333] When preparing the calibration curve, polystyrene standard foam with a molecular weight of 104 to 24,600 g / mol was used.

[0334]

[0335] (2) AEM evaluation

[0336] (2-1) AEM Sample Preparation

[0337] Step 1: Membrane Manufacturing

[0338] 2.0 g of the ion-conducting polymer prepared in the above example or comparative example was placed in a 70 ml vial and sufficiently dissolved in the solvent dimethylsulfoxide (DMSO, 35 g). The resulting polymer solution was filtered through a cotton filter to remove impurities contained in the polymer solution. The polymer solution from which impurities had been removed was spread-cast onto a glass plate measuring 18 cm x 18 cm, and then dried in an oven at 70°C for at least 24 hours. After drying was complete, the glass plate was collected, and a membrane was obtained.

[0339]

[0340] Step 2: Preprocessing

[0341] The membrane prepared in Step 1 above has a counter ion of quaternary ammonium functional group I - or Br - This membrane can change the counter ion depending on the purpose, and this process is called doping. Depending on the doping solution, Cl -, HCO3 - , OH - It is possible to manufacture AEM containing counter ions in the form of anions. In addition, H2PO4 - It is also possible to manufacture PEMs containing phosphate anion forms such as that.

[0342]

[0343] A. Chloride Doping (for IEC measurement)

[0344] The membrane prepared in Step 1 above was placed in a 1M NaCl aqueous solution at room temperature, and ion exchange was performed for at least 24 hours. After the ion exchange was completed, the membrane was removed and thoroughly washed multiple times with distilled water. To ensure the removal of residual NaCl, the washed membrane was stored in distilled water for at least 24 hours, then dried and used.

[0345]

[0346] B. Hydroxide Doping (for IC, WU measurement, and MEA manufacturing)

[0347] The membrane prepared in Step 1 was placed in a 1M aqueous NaOH solution in an environment where CO2 was completely blocked, such as inside an argon-atmosphere glove box, and ion exchange was performed for at least 24 hours. After the ion exchange was completed, the membrane was removed and thoroughly washed multiple times with distilled, deionized, Ar-gas bubbled water. To ensure the complete removal of residual NaOH, the washed membrane was washed multiple times with distilled water, then immersed in distilled water for at least 24 hours before use. Since the membrane ion-exchanged into the hydroxyl ion form forms bicarbonate ions within minutes upon contact with CO2 in the air, contact with CO2 was avoided.

[0348]

[0349] (2-2) thickness

[0350] The thickness of the ion-exchanged membrane prepared in Step 2 of the above (2-1) AEM Sample preparation was measured using a thickness gauge (ID C0512NXBS, manufactured by Mitutoyo). The values ​​listed in Tables 1 and 2 below are average values ​​obtained by measuring 20 parts.

[0351]

[0352] (2-3) Ion Exchange Capacity (IEC)

[0353] According to the methods disclosed in Journal of polymer science, part B: Polymer Physics 2013, 51(24), 1736-1742 and Macromolecules 2009, 42(21), 8316-8321 1 The IEC value was measured through H-NMR analysis:

[0354] < 1 H-NMR Analysis Conditions>

[0355] Instrument used: 600MHz Bruker NMR

[0356] acquisition time 2.73s

[0357] delay time 1s

[0358] number of scans 128

[0359] pulse 30°

[0360] solvent CDCl3

[0361] Sample concentration: 2.5 wt%

[0362]

[0363] (2-3) Ion Conductivity (IC)

[0364] Ion conductivity was measured using a 4-probe electrode (BekkTech Membrane Conductivity Test System) to determine in-plane ion conductivity. In fuel cell systems, to measure IC, resistance values ​​are checked according to changes in relative humidity (RH) at a specific temperature. The water electrolysis system differs in that resistance values ​​are measured by completely immersing the measurement cell in DI water so that the RH becomes 100% at a specific temperature.

[0365] Since measurements were taken using samples doped with hydroxide ions, all pretreatment processes were carried out in a CO2-free atmosphere, such as a glove box. During the IC measurement process, Ar gas was continuously purged from the container holding the measurement cell to prevent the membrane from being exposed to CO2. A specimen measuring 4 cm in width and 0.7 cm in length (actual measurement values ​​applied per sample) was mounted in the glove box onto a measurement cell (4-probe electrode cell) and rapidly transferred to a container holding water for conductivity measurement using an Ar bag.

[0366] After sealing the container, it was connected to the IC measurement equipment (BekkTech Membrane Conductivity Test System) under Ar gas purge conditions. The IC values ​​for each given temperature were measured. Using the resistance value measured at 60℃, the IC was calculated according to Equation 2 below (BekkTech Conductivity Testing Software).

[0367] [Mathematical Formula 2]

[0368] Ion Conductivity (σ, mS / cm) = L / (RХWХT)

[0369] In the above mathematical formula 2,

[0370] L is the distance (cm) between Pt probes inside the measuring cell, which is 4.2 mm in this experimental example, and

[0371] R is the measured resistance value of the membrane (Ω),

[0372] W is the width (width, cm) of the membrane doped with hydroxyl ions,

[0373] T is the thickness (thickness, cm) of a membrane doped with hydroxide ions.

[0374]

[0375] In addition, resistance values ​​at 60℃, 70℃, and 80℃ were measured, respectively, and the IC was calculated according to the above mathematical formula 2.

[0376]

[0377] (2-4) WU (Water Uptake) and Swelling Ratio

[0378] WU measures the ratio of moisture absorbed per unit mass. Since the weight change of an AEM sample doped with hydroxide ions is measured, the experiment was conducted in a glove box under an argon atmosphere to prevent contact with CO2 as much as possible.

[0379] Hydroxide ion으로 doping 된 membrane을 1M KOH 수용액에서 24시간 이상 침지한 후 꺼내어, KimWipe를 이용하여 membrane 표면의 수분을 가볍게 쓸어 내듯이 닦아내었다. 이후 Membrane의 중량을 측정하였다(W wet ). After drying the above membrane in an 80°C vacuum oven for more than 15 hours, the weight was measured (W dry WU was calculated according to the following mathematical formula 3 using the measured values.

[0380] [Mathematical Formula 3]

[0381] WU (wt%) = (W wet -W dry )Х100 / W dry

[0382]

[0383] The swelling ratio represents the rate of change in the physical size of a membrane due to water absorption. The swelling ratio can be measured using a sample that measures water uptake.

[0384] Specifically, the hydroxide ion-doped membrane was immersed in a 1M KOH aqueous solution for at least 24 hours, then removed, and the moisture on the membrane surface was wiped off lightly using a KimWipe. Subsequently, the length of the membrane was accurately measured in mm and recorded (L wet ).

[0385] After washing the measured membrane five times with pure water and drying it in an 80°C vacuum oven for more than 15 hours, the length was accurately measured to the millimeter and recorded (L dry After comparing with the initially measured size, the swelling ratio was calculated according to the following mathematical formula 4.

[0386] [Mathematical Formula 4]

[0387] Swelling Ratio (%) = [(L wet -L dry )Х100] / L dry

[0388] The measurement results are shown in Table 1 and Table 2 below.

[0389]

[0390] Example No. AEM sample Mw (kDa) Thickness (μm) IEC (meq. / g) OH - counter ion formCal.Exp. aWU(wt%)Swelling(%)σ(mS / cm)@60℃σ (mS / cm)@70℃σ (mS / cm)@80℃1mQUP-N2(47)-co-N1(53)217552.382.0387201121271492pQUP-N2(48)-co-N1(52)1 25552.392.057312971131253mQUP-N2(52)-co-N1(48)217432.442.0895221021151304mQUP-N2(5 0)-co-N1(50)202412.411.958324951121275mQUP-N2(42)-co-N1(58)217602.332.049421100121 1366mQUP-N2(30)-co-N1(70)217662.201.94821874931097mQUP-N2150792.952.481444789101110

[0391] Comparative Example No. AEMS sample Mw (kDa) Thickness (μm) IEC (meq. / g) OH - counter ion formCal.Exp. a WU(wt%)Swelling(%)σ(mS / cm)@60σ (mS / cm)@70℃σ (mS / cm)@80℃1mTP-N2(47)-co-N1(53)154652.722.3620919971011072pQUP-N1125501.881.67105206774863BP-N1113802.632.271252 86677814mTP-N115435-402.191.946924891031185FAA-3-50NA501.6-2.11.8810532NANA656FAA-3-PK-75NA751.2-1.41.50429NANA31

[0392] In the table above, 'NA' means that it was not measured.

[0393] In addition, 'a' indicates that the value was measured by titration using a METTLER TOLEDO G20S Compact Titrator.

[0394] As a result of the experiment, the ion-conducting polymers of the examples, compared to the polymers of the comparative examples, allowed for easy control of molecular weight and ion exchange capacity (IEC), and exhibited excellent ion conductivity, WU, and swelling characteristics at an equivalent or higher level. Meanwhile, the ion-conducting polymer of Example 2 exhibited lower WU and swelling characteristics compared to other examples due to its structure containing pQUP, but showed excellent results in terms of ion conductivity at an equivalent or higher level. In addition, the ion-conducting polymer of Example 6 also exhibited relatively lower swelling characteristics compared to other examples, but at 60°C The above demonstrates an ion conductivity level suitable for use as an ion exchange membrane.

[0395] From the experimental results described above, it can be seen that when the ion-conducting polymer of the present invention is used as an ion exchange membrane, excellent dimensional stability can be achieved while maintaining high ion conductivity and excellent solubility.

Claims

1. Ionic conductive polymer comprising repeating units represented by the following chemical formulas 1 to 4: [Chemical Formula 1] [Chemical Formula 2] [Chemical Formula 3] [Chemical Formula 4] In the above chemical formulas 1 to 4, mQUP is a substituted or unsubstituted m-quaterphenylene, and pQUP is a substituted or unsubstituted p-quaterphenylene, and R a and R c Each is independently represented by the following chemical formula 5, and R b and R d Each is independently represented by the following chemical formula 6, and p, q, r, and s are each independently greater than or equal to 0, provided that p, q, r, and s are not simultaneously zero integers, and If r is an integer greater than or equal to 1, at least one of p, q, and s is not 0, and [Chemical Formula 5] [Chemical Formula 6] In the above chemical formulas 5 and 6, R 1 , R 2 and R 3 Each is an independently substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, and R 11 to R 13 , and R 21 to R 25 Each is independently a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or two adjacent groups are connected to each other to form an N-containing heterocyclic structure, and Y1, Y2, and Y3 are each independently anions, and * indicates the connection position.

2. In Paragraph 1, Ionic conductive polymer, wherein mQUP is represented by the following chemical formula 7-1 and pQUP is represented by the following chemical formula 7-2: In the above formula, * represents the joining position.

3. In Paragraph 1, R 1 , R 2 and R 3 ion-conducting polymers, each independently a pentylene group or a hexylene group.

4. In Paragraph 1, R 11 to R 13 , and R 23 to R 25 Each is independently a methyl group, an ethyl group, or a phenyl group, or two adjacent groups are connected to each other as R 11 to R 13 , or R 23 to R 25 Ionic conductive polymer that forms a piperidine structure together with this bonded nitrogen atom.

5. In Paragraph 1, R 21 and R 22 Each is independently a methyl group, an ethyl group, or a phenyl group, or is connected to each other as R 21 and R 22 Ionic conductive polymer that forms a piperidine structure with bonded nitrogen atoms.

6. In Paragraph 1, Y1, Y2 and Y3 are ion-conducting polymers, each independently being a chloride ion, bromide ion, iodide ion, hydroxide ion, bicarbonate ion, dihydrogen phosphate ion, hydrogen phosphate ion, or phosphate ion.

7. In Paragraph 1, R a and R c ion-conducting polymers, each independently one of the following: In the above formula, Y1 is as defined in claim 1.

8. In Paragraph 1, R b and R d ion-conducting polymers, each independently one of the following: In the above formula, Y2 and Y3 are as defined in claim 1.

9. In Paragraph 1, Ionic conductive polymer, which is a compound represented by any one of the following chemical formulas 1a to 1g: [Chemical Formula 1a] [Chemical Formula 1b] [Chemical Formula 1c] [Chemical Formula 1d] [Chemical Formula 1e] [Chemical Formula 1f] [Chemical formula 1g] In the above chemical formulas 1a to 1g, Y1, Y2, Y3, p, q, r, and s are as defined in claim 1.

10. A first step of preparing a polymer precursor having a halogen pendant group by reacting one or more of quaternphenyls among m-quaternphenyl and p-quaternphenyl with a compound represented by the following chemical formula 8 in the presence of a strong acid; A second step of preparing a polymer precursor having a cationic pendant group by reacting the polymer precursor having the above halogen pendant group with one or more of a compound represented by the following chemical formula 9 and a tertiary amine; A third step of changing the counter ion by reacting the polymer precursor having the above-mentioned cation pendant group or the membrane of the polymer precursor containing the same with a basic ion aqueous solution or an acidic ion aqueous solution; comprising Method for manufacturing an ion-conducting polymer according to claim 1: [Chemical Formula 8] In the above chemical formula 8, X is a halogen group, and p is an integer from 1 to 10, and [Chemical Formula 9] In the above chemical formula 9, R 31 to R 33 Each is independently a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or two adjacent groups are connected to each other to form an N-containing heterocyclic structure, and R 34 and R 35 Each is independently a hydrogen or methyl group, and R 4 is a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, and X is a halogen.

11. In Paragraph 10, A manufacturing method wherein the first step above is performed by dissolving one or more of m-quaternphenyl and p-quaternphenyl and a compound represented by the chemical formula 8 in a halogenated hydrocarbon solvent under a nitrogen atmosphere, and then reacting them by adding a strong acid.

12. In Paragraph 10, A method for preparing a compound represented by the above chemical formula 8, wherein the compound is 7-bromo-1,1,1-trifluoroheptan-2-one, 8-bromo-1,1,1-trifluorooctane-2-one, or 9-bromo-1,1,1-trifluorononan-2-one.

13. In Paragraph 10, A method of manufacturing in which the compound represented by the above chemical formula 8 is added in a molar ratio of 1 to 3 per 1 mole of quarterphenyl.

14. In Paragraph 10, A method for manufacturing the above strong acid, wherein the strong acid is trifluoromethanesulfonic acid, trifluoroacetic acid, toluenesulfonic acid, or methanesulfonic acid.

15. In Paragraph 10, A method for preparing a compound represented by the above chemical formula 9, which is N-(dimethylaminohexyl)-N,N,N-trimethylammonium iodide, 6-(dimethylaminohexyl)-1-methylpiperidinium iodide or 1,1-dimethyl-4-(3-(1-methylpiperidin-4-yl)propyl)piperidin-1-ium iodide.

16. In Paragraph 10, A method for manufacturing in which the above tertiary amine is trimethylamine, triethylamine, tripropylamine, 1-methylpiperidine, 1-methylpyrrolidine, or 1,2,2,6,6-pentamethylpiperidine.

17. In Paragraph 10, A method for manufacturing, wherein the second step is performed by reacting the polymer precursor having the halogen pendant group with the compound represented by the chemical formula 9 or a tertiary amine; or by reacting the polymer precursor having the halogen pendant group with the compound represented by the chemical formula 9 and then reacting it with a tertiary amine.

18. In Paragraph 10, The above third step is a manufacturing method in which a polymer precursor having a cation pendant group prepared in the above second step is dissolved in a solvent to prepare a polymer solution, a membrane is formed using the solution, and then a basic ion aqueous solution or an acidic ion aqueous solution is introduced into the prepared membrane and reacted.

19. In Paragraph 10, A manufacturing method further comprising the step of, prior to the first step above, heating 3-iodobiphenyl or 4-iodobiphenyl to 120 to 150 ℃ in the presence of a palladium catalyst and an alkali metal carbonate to produce quaternphenyl.

20. An ion-conducting membrane comprising an ion-conducting polymer according to claim 1.

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