Polymer, its manufacturing method, and anion exchange material containing the same

Abstract

The present invention provides a polymer having a stable structure, a method for producing the same, and an anion exchange material containing the same that is highly efficient.

Description

[Technical Field]

[0001] The present invention relates to polymers, methods for their preparation, and anion exchange materials containing same. [Background technology]

[0002] At a time when the development of environmentally friendly fuels is a hot topic, water electrolysis is the only commercialized technology capable of producing green hydrogen perfectly. Water electrolysis technologies can be divided into three categories based on their detailed components: Proton Exchange Membrane Electrolysis Cell (PEMEC), Alkaline Electrolysis Cell (AEC), and Solid Oxide Electrolysis Cell (SOEC). With a history spanning more than 100 years, AEC is a mature field in both market and technology, making it difficult to expect savings in equipment production and operating costs through technological development. Furthermore, AEC's low hydrogen production density necessitates expansion of production scale and the resulting increase in equipment size, making it difficult to ensure economic viability. PEMEC, a relatively recently commercialized technology, can quickly produce high-purity, high-pressure hydrogen using compact equipment, offering significant potential for reducing production and operating costs through technological development. However, as it is a technology that was recently commercialized, there is no long-term operating data available, making it difficult to guarantee stability. Furthermore, the cost of the separator (or bipolar plate) material, which must be used due to the acidic operating conditions, and its processing costs can account for a large proportion of production costs, acting as a burden. SOECs have the unique advantage of being able to be used as either an electrolyzer or a fuel cell with the same configuration, depending on the operating method. However, because the solid oxide catalyst component is vulnerable to physical shocks, they can only be stably applied to stationary facilities. Furthermore, because the temperature of the water used in the process is extremely high, they must be installed near places where extremely high-temperature water is generated, such as steel mills or nuclear power plants.

[0003] Therefore, anion exchange membrane electrolysis cells (AEMEC) have been proposed as an alternative to solve the problems of existing water electrolysis methods. AEMEC has the advantages of being able to produce high-density hydrogen at a similar density to PEMEC, requiring smaller facilities, and using AEC materials for low production costs. However, the biggest obstacle to the commercialization of AEMEC is the need to develop an anion exchange membrane with proven durability. Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention seeks to provide polymers, methods for their preparation, and anion exchange materials containing the same.

[0005] Specifically, the present invention provides a polymer having high ionic conductivity and a stable structure, a method for producing the same, and an anion exchange material having excellent efficiency.

[0006] The present invention also provides a method for producing a polymer that can be used as an anion exchange material without requiring a separate separation or purification process. [Means for solving the problem]

[0007] The present invention provides a polymer comprising a repeating unit represented by the following Chemical Formula 1 or Chemical Formula 2:

[0008] [ka]

[0009] [ka]

[0010] In the above chemical formula 1 or chemical formula 2, n is an integer between 100 and 100,000; A is NR1 or CR2R3, R1 is a substituted or unsubstituted C 1-10 is alkyl, R2 and R3 are each independently hydrogen or substituted or unsubstituted C 1-10 is alkyl, R4 to R6 are each independently a substituted or unsubstituted C 1-10 alkyl, or R4 and R5 combine to form C 3-12 Forming a ring, L1 and L2 are each independently a substituted or unsubstituted C 1-12 It is alkylene.

[0011] The present invention also provides an anion exchange material containing the polymer.

[0012] The present invention also provides a method for preparing a polymer, comprising the steps of: (1) polymerizing a polymer by reacting a substituted or unsubstituted carbazole or fluorene with a halogen-substituted alkyl trifluoromethyl ketone in the presence of an acid catalyst; and (2) substituting a substituted or unsubstituted amine into the polymer prepared in step 1 to form a polymer represented by Formula 1 or Formula 2 containing a quaternary ammonium ion. [Effects of the Invention]

[0013] The polymer according to the present invention can be structurally stable without containing ether bonds in the backbone.

[0014] In addition, the anion exchange material containing the polymer according to the present invention has high ionic conductivity and is highly efficient.

[0015] Furthermore, an anion exchange material containing the polymer according to the present invention can exhibit stable properties under high temperature basic conditions.

[0016] Furthermore, the method for producing a polymer according to the present invention does not require a separate separation or purification process because it does not use a metal catalyst.

[0017] Furthermore, a highly pure product can be obtained in high yield without any additional separation or purification steps. [Brief explanation of the drawings]

[0018] [Figure 1] 10 is a graph showing a comparison of the amount of electricity consumed in Example 3 and the comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0019] In the present invention, terms such as "first" and "second" are used to describe various components, and the terms are used only to distinguish one component from another.

[0020] Furthermore, the terms used in this specification are merely used to describe exemplary embodiments and are not intended to limit the present invention. A singular expression includes a plural expression unless the context clearly dictates otherwise. In this specification, terms such as "comprises," "has," or "has" are intended to specify the presence of embodied features, numbers, steps, components, or combinations thereof, and should be understood not to preclude the presence or addition of one or more other features, numbers, steps, components, or combinations thereof.

[0021] Furthermore, in the present invention, when it is said that each layer or element is formed "on" or "on" each layer or element, it means that each layer or element is formed directly on each layer or element, or it means that other layers or elements may be additionally formed between each layer, on the object, or on the substrate.

[0022] While the present invention can be modified in various ways and can take various forms, the following detailed description will be given by way of example of specific embodiments, but it should be understood that the present invention is not intended to be limited to the specific disclosed embodiments, and that the present invention encompasses all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention.

[0023] The present invention provides a polymer produced using an acid-catalyzed polymerization reaction, a method for producing the same, and an anion exchange material containing the same.

[0024] In particular, the present invention provides a polymer produced by introducing a quaternary ammonium functional group into a polymer obtained by polymerizing a flat-structured aromatic compound, such as carbazole or fluorene, and a ketone compound through an acid-catalyzed polymerization reaction, a method for producing the polymer, and an anion exchange material containing the polymer.

[0025] The polymer of the present invention will now be described in detail.

[0026] The polymer of the present invention comprises a repeating unit represented by the following formula 1 or 2:

[0027] [ka]

[0028] [ka]

[0029] In the above chemical formula 1 or chemical formula 2, n is an integer between 100 and 100,000; A is NR1 or CR2R3, R1 is a substituted or unsubstituted C 1-10 is alkyl, R2 and R3 are each independently hydrogen or substituted or unsubstituted C 1-10 is alkyl, R4 to R6 are each independently a substituted or unsubstituted C 1-10 alkyl, or R4 and R5 combine to form C 3-12 Forming a ring, L1 and L2 are each independently a substituted or unsubstituted C 1-12 It is alkylene.

[0030] Preferably, Chemical Formula 1 can be represented by the following Chemical Formula 1-1 or Chemical Formula 1-2.

[0031] [ka]

[0032] [ka]

[0033] n is the number of repeating units in the polymer, specifically, n is an integer of 100 to 100,000.

[0034] Preferably, R1 is methyl; ethyl; or hexyl.

[0035] Preferably, R2 and R3 are each independently hydrogen.

[0036] Preferably, R4 to R6 are each independently methyl; or R4 and R5 are bonded to each other to form a 6-membered alkyl ring containing N, and R6 is methyl. That is, the ammonium group in [Chemical Formula 1] having R4 to R6 substituents is trimethylammonium; or 2-methylpiperidinium.

[0037] Preferably, L1 is pentylene.

[0038] The compound represented by chemical formula 2 is formed by bonding the ammonium-substituted substituents of adjacent polymers to each other to form C 1-10The structure includes a substituted or unsubstituted bis-ammonium having a hydrocarbon bridge, L2. Preferably, L2 is pentylene. More preferably, the substituted or unsubstituted bis-ammonium structure may be 1,5-bis(dimethylpentylammonium)pentane.

[0039] The bridges of the compound represented by Chemical Formula 2 are randomly arranged between the two polymer chains, resulting in a more densely crosslinked crosslinked membrane.

[0040] The polymer may contain 100 to 10,000 repeating units of Chemical Formula 1 or Chemical Formula 2.

[0041] The polymer may have a weight average molecular weight (Mw) of 40,000 to 4,000,000 Da.

[0042] The polymer containing the repeating unit represented by Formula 1 or Formula 2 is any one selected from the group consisting of:

[0043] [ka]

[0044] The present invention also provides an anion exchange material containing the polymer. Specifically, the anion exchange material can be used in anion exchange membrane water electrolysis to form membranes and ionomers.

[0045] The method for producing the polymer of the present invention will now be described in detail.

[0046] The method for producing a polymer of the present invention comprises the steps of: polymerizing a polymer by reacting a substituted or unsubstituted carbazole or fluorene with a halogen-substituted alkyl trifluoromethyl ketone under acid catalysis (Step 1); and Step 2: Substituting a substituted or unsubstituted amine into the polymer prepared in Step 1 to form a polymer represented by Formula 1 or Formula 2 containing a quaternary ammonium ion; may include:

[0047] Step 1 can be represented by reaction scheme 1.

[0048] [ka]

[0049] Step 2 can be represented by reaction scheme 2.

[0050] [ka]

[0051] The substituted carbazole or fluorene in step 1 can be prepared by reacting 9H-carbazole or fluorene with an alkyl halide under basic conditions. The base can be potassium hydroxide or sodium hydroxide. The alkyl halide can be iodomethane or iodohexane. The substituted carbazole can be 9-methyl-9H-carbazole, 9-ethyl-9H-carbazole, or 9-hexyl-9H-carbazole.

[0052] The step 2 is to substitute a substituted or unsubstituted diamine into the prepared polymer 2 or more to form C 1-10 The method may further include a step (Step 2-1) of forming a polymer containing a substituted or unsubstituted bis-ammonium having a hydrocarbon bridge. (Step 2-1) can be represented by Reaction Scheme 2-1. Specifically, the method of the present invention may be carried out after (Step 2).

[0053] [ka]

[0054] In the reaction scheme, R1, R2, R3, R4, R5, R6, L1, L2, and n are defined as in Formula 1 or Formula 2, and X is a halogen element. Specifically, X may be chloro, bromo, or iodo.

[0055] The bridges formed through Reaction Scheme 2-1 can be formed at any position where a substituted or unsubstituted diamine is bonded in the polymer chain, and can be formed randomly, thereby obtaining a crosslinked film with a denser crosslinking reaction.

[0056] The acid catalyst in step 1 may be a superacid, specifically trifluoroacetic acid, trifluoromethanesulfonic acid, methanesulfonic acid, or a mixture thereof.

[0057] The step 1 can be carried out in an organic solvent, specifically, in dichloromethane.

[0058] The substituted or unsubstituted amine in (Step 2) may be selected from the group consisting of trimethylamine, triethylamine, and methylpiperidine, as shown below:

[0059] [ka]

[0060] The substituted or unsubstituted diamine in (Step 2-1) may be selected from the group consisting of the following compounds:

[0061] [ka]

[0062] Preferred examples are presented below to aid in understanding the invention, but the following examples are merely for illustrative purposes and are not intended to limit the invention. [Example]

[0063] The reagent information used in Examples 1 to 5 is as shown in Table 1 below.

[0064] [Table 1]

[0065] Example 1: Synthesis of Polymer 1 Potassium hydroxide (1,010 mg) was dissolved in N,N-dimethylacetamide (2 ml). 9H-carbazole (500 mg) was added and stirred for 30 minutes. Iodomethane (0.28 ml) was added and stirred. The progress of the reaction was monitored by TLC (Thin Layer Chromatography). After confirming completion, DI water (2 ml) was added to the reaction mixture. The final reaction mixture was filtered to obtain the solid N-methylcarbazole, which was then dried.

[0066] The reaction product, solid N-methylcarbazole (442 mg) and 7-bromo-1,1,1-trifluoroheptan-2-one (843 mg), were added to dichloromethane (2 ml) and stirred under a nitrogen atmosphere. The reaction mixture was immersed in an ice bath, and trifluoromethanesulfonic acid (0.34 ml) was added dropwise as an acid catalyst. The ice bath was removed, and the reaction mixture was warmed to room temperature and stirred. When the viscosity of the reaction mixture increased, it was slowly poured into methanol (100 ml). The resulting solid was washed several times with methanol and dried to obtain a polymer with a weight-average molecular weight of 96,340 Da.

[0067] The polymer (1,000 mg) was dissolved in N,N-dimethylacetamide (10 ml). The amine reagent trimethylamine (1.73 ml) was added and thoroughly stirred at room temperature. After confirming the completion of the reaction, the reaction mixture was slowly poured into diethyl ether (100 ml). The solids in the solution were washed several times with diethyl ether, filtered, and dried to obtain the final product of Example 1.

[0068] [ka]

[0069] Example 2: Synthesis of Polymer 2 N-ethylcarbazole reagent was purchased.

[0070] N-ethylcarbazole (460 mg) and 7-bromo-1,1,1-trifluoroheptan-2-one (815 mg) were added to dichloromethane (1.75 ml) and stirred under a nitrogen atmosphere. The reaction mixture was immersed in an ice bath, and trifluoromethanesulfonic acid (0.33 ml) was added dropwise as an acid catalyst. The ice bath was removed, and the reaction mixture was warmed to room temperature and stirred. When the viscosity of the reaction mixture increased, it was slowly poured into methanol (100 ml). The resulting solid was washed several times with methanol and then dried to obtain a polymer with a weight-average molecular weight of 89,892 Da.

[0071] The polymer (850 mg) was dissolved in N,N-dimethylacetamide (8.14 ml). The amine reagent trimethylamine (1.43 ml) was added to the reaction mixture and stirred thoroughly at room temperature. After confirming the completion of the reaction, the reaction mixture was slowly poured into diethyl ether (100 ml). The solids in the solution were washed several times with diethyl ether, filtered, and dried to obtain the final product.

[0072] [ka]

[0073] Example 3: Synthesis of Polymer 3 Potassium hydroxide (670 mg) was dissolved in N,N-dimethylacetamide (4 ml). 9H-carbazole (665 mg) was added to the mixture and stirred for 30 minutes. Iodohexane (0.88 ml) was added to the mixture and stirred. The progress of the reaction was monitored by TLC (thin layer chromatography). After confirming the completion of the reaction, DI water (4 ml) was added to the reaction mixture. The final reaction mixture was filtered and dried to obtain solid N-hexylcarbazole.

[0074] The obtained N-hexylcarbazole (1,046 mg) and 7-bromo-1,1,1-trifluoroheptan-2-one (1,234 mg) were added to dichloromethane (3.51 ml) and stirred under a nitrogen atmosphere. The reaction mixture was immersed in an ice bath, and the acid catalyst trifluoromethanesulfonic acid (0.59 ml) was added dropwise. The ice bath was removed, and the reaction mixture was warmed to room temperature and stirred. When the viscosity of the reaction mixture increased, it was slowly poured into methanol (100 ml). The resulting solid was washed several times with methanol and dried to obtain a polymer with a weight-average molecular weight of 96,340 Da.

[0075] The polymer (1,803 mg) was dissolved in N,N-dimethylacetamide (10.9 ml). The amine reagent trimethylamine (2.68 ml) was added to the reaction mixture and thoroughly stirred at room temperature. After confirming the completion of the reaction, the reaction mixture was slowly poured into diethyl ether (200 ml). The solids in the solution were washed several times with diethyl ether, filtered, and dried to obtain the final product.

[0076] [ka]

[0077] Example 4: Synthesis of Polymer 4 Fluorene reagent was purchased commercially.

[0078] Fluorene (420 mg) and 7-bromo-1,1,1-trifluoroheptan-2-one (750 mg) were added to dichloromethane (1.75 ml) and stirred under a nitrogen atmosphere. The reaction mixture was immersed in an ice bath, and the acid catalyst trifluoromethanesulfonic acid (0.67 ml) was added dropwise. The ice bath was then removed, and the reaction mixture was warmed to room temperature and stirred. When the viscosity of the reaction mixture increased, it was slowly poured into methanol (100 ml). The resulting solid was washed several times with methanol and dried to obtain a polymer with a weight-average molecular weight of 264,294 Da.

[0079] The resulting polymer (1,000 mg) was dissolved in N,N-dimethylacetamide (9.57 ml). The amine reagent trimethylamine (1.81 ml) was added to the reaction mixture and thoroughly stirred at room temperature. After confirming the completion of the reaction, the reaction mixture was slowly poured into diethyl ether (100 ml). The solid content in the solution was washed several times with diethyl ether, filtered, and dried to obtain the final product.

[0080] [ka]

[0081] Example 5: Synthesis of Polymer 5 Potassium hydroxide (670 mg) was dissolved in N,N-dimethylacetamide (4 ml). 9H-carbazole (665 mg) was added to the mixture and stirred for 30 minutes. Iodohexane (0.88 ml) was added to the mixture and stirred. The progress of the reaction was monitored by TLC (thin layer chromatography). After confirming completion, DI water (4 ml) was added to the reaction mixture. The final reaction mixture was filtered and dried to obtain solid N-hexylcarbazole.

[0082] The N-hexylcarbazole (1,046 mg) synthesized in the above reaction and 7-bromo-1,1,1-trifluoroheptan-2-one (1,234 mg) were added to dichloromethane (3.51 ml) and stirred under a nitrogen atmosphere. The reaction mixture was immersed in an ice bath, and the acid catalyst trifluoromethanesulfonic acid (0.59 ml) was added dropwise. The ice bath was then removed, and the reaction mixture was warmed to room temperature and stirred. When the viscosity of the reaction mixture increased, it was slowly poured into methanol (100 ml). The resulting solid was washed several times with methanol and then dried to obtain a polymer with a weight-average molecular weight of 96,340 Da.

[0083] The polymer (1,803 mg) obtained above was dissolved in N,N-dimethylacetamide (10.9 ml). The amine reagent trimethylamine (0.89 ml) was added to the reaction mixture and stirred at room temperature. The progress of the reaction was confirmed by H-NMR measurement. After confirming the completion of the reaction, the reaction mixture was slowly poured into diethyl ether (200 ml). The solid content in the solution was washed several times with diethyl ether, filtered, and dried.

[0084] The reaction product (2,000 mg) was dissolved in N,N-dimethylacetamide (18 ml). N,N,N',N'-tetramethylhexamethylenediamine (49 mg) was added to the reaction mixture and stirred at room temperature. Before the reaction mixture aggregated into a single mass, it was cast onto a glass plate and dried to obtain the final product.

[0085] [ka]

[0086] Comparative Example A commercial anion exchange membrane, FAA-3-50, was prepared.

[0087] Experimental Example 1 - Ionic Conductivity Ionic conductivity was measured using a Bekkech BT-512.

[0088] A membrane sample measuring 0.7 cm in width and 4 cm in length was prepared. The thickness of the sample was measured and the surface was washed with distilled water. The washed sample was immersed in a 1 M KOH aqueous solution and stored at room temperature for 24 hours. The sample was then thoroughly washed, fastened to a 4-probe cell, immersed in distilled water, connected to the instrument, and its conductivity was measured at 80°C using the conductivity measurement program.

[0089] Experimental Example 2 - Stability under high temperature basic conditions A 100 ml Teflon (registered trademark) sealed container was filled with 1 M KOH aqueous solution, and a membrane sample measuring 3 cm in length and width was placed inside, and stored at 80° C. for 1000 hours. After the time had passed, the condition of the membrane was checked with the naked eye.

[0090] [Table 2]

[0091] Experimental Example 3: Electricity consumption measurement Anode and cathode electrodes were coated on both sides of the membrane, which was 5 cm wide and 5 cm long. 2 The electrode was connected to a wire and the voltage change due to the current density was measured using a potentiostat (measurement conditions: 1M KOH, 60°C).

[0092] As a result, when comparing Example 3 with the commercial anion exchange membrane FAA-3-50, Example 3 exhibited a lower voltage value than the Comparative Example in the high current density range, as shown in Figure 1. This result indicates that the use of the polymer material of Example 3 results in less electricity consumption when producing the same amount of hydrogen.

Claims

1. A polymer comprising a repeating unit represented by the following chemical formula 1 or chemical formula 2: 【Chemistry 1】 n is an integer from 100 to 100,000; A is NR １ or CR ２ R ３ and R １ is a substituted or unsubstituted C １－１０ is alkyl, R ２ and R ３ are each independently hydrogen or substituted or unsubstituted C １－１０ is alkyl, R ４ ~R ６ are each independently substituted or unsubstituted C １－１０ alkyl or R ４ and R ５ are combined to form C ３－１２ Forming a ring, L １ and L ２ are each independently substituted or unsubstituted C １－１２ It is alkylene.

2. R １ is methyl; ethyl; or hexyl.

3. R ２ and R ３ and each independently represents hydrogen.

4. L １ The polymer of claim 1 , wherein is pentylene.

5. R ４ ~R ６ are each independently methyl; or R ４ and R ５ are bonded to each other to form a 6-membered alkyl ring containing N, and R ６ The polymer of claim 1 , wherein is methyl.

6. L in Chemical Formula 2 ２ The polymer of claim 1 , wherein is pentylene.

7. The polymer according to claim 1 , wherein the polymer including the repeating unit represented by Formula 1 is any one selected from the group consisting of: 【Chemistry 2】

8. An anion exchange material comprising the polymer according to any one of claims 1 to 7.

9. Step 1: Polymerizing a polymer by reacting a substituted or unsubstituted carbazole or fluorene with a halogen-substituted alkyl trifluoromethyl ketone under acid catalysis; and Step 2: Substituting a substituted or unsubstituted amine into the polymer prepared in Step 1 to form a polymer represented by Formula 1 or Formula 2 containing a quaternary ammonium ion; A method for producing a polymer, comprising:

10. The method for producing a polymer according to claim 9, wherein the acid catalyst in step 1 is trifluoroacetic acid, trifluoromethanesulfonic acid, or a mixture thereof.

11. The method for producing a polymer according to claim 9, wherein the step (1) is carried out in an organic solvent.

12. 10. The method for producing a polymer according to claim 9, wherein the substituted or unsubstituted amine in step 2 is selected from the group consisting of trimethylamine, triethylamine, and methylpiperidine.

13. The step 2 is to substitute a substituted or unsubstituted diamine into the prepared polymer 2 or more to form C １－１０ 10. The method of claim 9, further comprising forming a polymer comprising a substituted or unsubstituted bis-ammonium having a hydrocarbon bridge.

14. The method for producing a polymer according to claim 13, wherein the substituted or unsubstituted diamine is selected from the group consisting of the following compounds: 【Transformation 3】

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