WO2018199545A1 - Polyphenylene-based anion conductor, preparation method therefor, and use thereof - Google Patents

Abstract

The present invention relates to a polyphenylene-based anion conductor, a preparation method therefor, and a use thereof. More specifically, the present invention relates to: a polyphenylene-based anion exchange material, wherein a polyphenylene-based anion exchange polymer has a lower crossover of an active material compared with the commercially available cation exchange material Nafion115, leading to excellent column efficiency and wherein, structurally, a main chain of the polymer is formed of polyphenylene and thus the main chain is composed of only C-C bonds between benzene rings without containing a linker group having an electron donor characteristic, such as -O-, -S-, or -(CH2)n-, leading to excellent material dimensional stability; a preparation method therefor; and a redox flow battery obtained by applying the prepared polyphenylene-based anion polymer to a separator for a redox flow battery.

Description

Polyphenylene-based Anion Conductor, Method of Making and Use thereof

The present invention relates to a polyphenylene-based anion conductor, a method for producing the same, and a use thereof.

More specifically, it is a polyphenylene-based anion exchange material. Compared to commercially available cation exchange material, Nafion115, the crossover of the active material is lower, and thus the coulombic efficiency is excellent. Structurally, the polymer main chain is polyphenylene. Polyphenylene-based anion exchange with excellent dimensional stability because it consists of only CC bonds between benzene rings and does not contain electron donor linkages such as -O-, -S-, and-(CH ₂ ) _n -in the main chain The present invention relates to a redox flow battery in which a polymer, a method for preparing the same, and a polyphenylene-based anionic polymer prepared therein are applied to a separator for a redox flow battery.

This application claims priority based on Korean Patent Application No. 10-2017-0055111 filed on April 28, 2017, and all the contents disclosed in the specification and drawings of the application are incorporated in this application.

Efforts are being made to save fossil fuels or to apply renewable energy to more fields by improving the efficiency of use to solve the problems of fossil fuel depletion and environmental pollution.

One of them, the rechargeable battery provides a simple and efficient way of storing electricity, which makes it smaller and more portable, thus making efforts to use it as an intermittent auxiliary power source or as a power source for small appliances such as laptops, tablet PCs, and mobile phones. It is becoming. In particular, Redox Flow Battery (RFB) is a secondary battery that can store energy for a long time by repeating charging and discharging due to electrochemical reversible reaction of electrolyte. Since the stack and the electrolyte tank are configured independently of each other, there is an advantage that the design of the battery is free and the installation space is limited.

Currently used ion exchange material is Nafion, a perfluorinated cation exchange material. Nafion has excellent initial performance and durability, but due to its very high price and high crossover of active materials, it is suitable for practical applications. There is difficulty. In particular, in the case of Vanadium Redox Flow Battery (VRFB), which has a higher proportion of ion exchange materials in the total system price than energy conversion systems such as fuel cells, the price of the membrane material is increased in the commercialization and production of the system. It is the most important factor.

In addition, the continuous degradation of performance due to the crossover (vanadium ion) of the active material (vanadium ion) there is a problem that causes not only the reduction of the system life, but also the additional cost for the regeneration of the active material. Accordingly, development of a membrane material having low cost and low crossover of an active material is considered an urgent problem to be solved for commercialization of a vanadium redox flow battery.

In the prior art for the redox flow battery exchange membrane is a negative ion exchange membrane for vanadium redox flow battery, Korean Patent No. 1543079 discloses that polyethersulfone and polyphenylene sulfide sulfone, which are acid-stable engineering plastics, are block or randomly After preparing a copolymerized copolymer, a technique of chloromethylation to prepare in the form of a polymer gel and introducing an ion exchanger into the diaphragm is disclosed. Korean Patent No. 1062767 discloses polysulfone and polyphenylene sulfide. After dissolving the sulfone-block copolymerized copolymer with tetrachloroethane (1,1,2,2-tetrachloroethane: TCE), vanadium having a cation exchanger introduced into the copolymer by adding an ion exchanger introducing solvent and sulfonating reaction. Although a method for manufacturing a diaphragm for a redox flow secondary battery has been described, most of Future technologies in the main chain thereof _{-O-, -S-, - (CH 2} ) n - is a situation in which the electron donor as the limit of the cation exchange polymer comprising a linking group of characteristics such as.

Accordingly, the present inventors have diligently researched to find a low-cost ion exchange material using a hydrocarbon-based polymer, and as a result, the crossover of the active material is lower than that of Nafion115, which is a commercial cation exchange material, and thus the coulombic efficiency is excellent. The polymer main chain is made of polyphenylene, and does not contain the linking group of electron donor properties such as -O-, -S-,-(CH ₂ ) _n -in the main chain, and consists only of CC bonds between benzene rings. By using this excellent polyphenylene-based anion exchange polymer, it was confirmed that the permeability of the active material which is essentially a cation can be lowered, and the present invention was completed.

The present invention was developed to solve the above problems, and an object of the present invention is to provide a polyphenylene-based anion conductor having a low crossover of the active material compared to commercially available cation exchange material Nafion115 and thus improving the coulomb efficiency.

In addition, the present invention is a separator membrane for a redox flow battery and a redox flow battery using the same, characterized in that the polymer membrane formed by molding the polyphenylene-based anion exchange polymer itself or a composite membrane prepared by complexing the polyphenylene-based anion exchange polymer with a support. To provide.

The present invention provides a polyphenylene-based polymer, which is prepared by copolymerization of a hydrophilic unit monomer of Formula 1 and a hydrophobic unit monomer of Formula 2 to solve the above problems.

<Formula 1>

<Formula 2>

In Formula 1 and Formula 2, A ₁ and A ₂ may be the same as or different from each other, which is-(C = O)-, -P (= O)-, -CF _2- , Any one selected from -C (CF ₃ ) ₂ -and SO _2- , X is any one of chlorine (Cl), bromine (Br) or iodine (I), and R ₁ , R ₂ , R ₃ , R ₄ And R ₅ are all hydrogen atoms or at least one fluorine atom, aryl group, perfluoroalkyl group, or a perfluoroalkylaryl group, optionally including one or more oxygen, nitrogen, or sulfur atoms in the chain, purple It is a fluoroaryl group and -O- perfluoroaryl group.

The polymer according to the invention is characterized in that it has a chemical structure of formula (3).

<Formula 3>

In Formula 3, m and n are positive integers in the range of 0.1 ≦ n / m ≦ 100, and A ₁ and A ₂ may be the same as or different from each other, which is a single bond or an electron drawer-(C = O )-, -P (= O)-, -CF _2- , -C (CF ₃ ) ₂ -and SO _2- , and R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are all A hydrogen atom or at least one fluorine atom, an aryl group, a perfluoroalkyl group, or optionally a perfluoroalkylaryl group, perfluoroaryl group containing one or more oxygen, nitrogen, or sulfur atoms in its chain; and -O- perfluoroaryl group.

In another aspect, the present invention provides a halogenated polyphenylene-based polymer, which is prepared by the halogenation reaction of the polymer having a chemical structure of the formula (4).

<Formula 4>

In Formula 4, m 'and n are positive integers, m''is 0 or a positive integer, and 0.1 ≦ n / (m' + m '') ≤ 100, and 0≤ m '' / m ' ≤ 100, A ₁ and A ₂ may be the same or different from each other, which is-(C = O)-, -P (= O)-, -CF _2- , -C as a single bond or electron drawer. (CF ₃ ) ₂ -and SO _2- , W is any one of chlorine (Cl), bromine (Br) or iodine (I), and R ₁ , R ₂ , R ₃ , R ₄ and R ₅ is all hydrogen atoms or at least one fluorine atom, aryl group, perfluoroalkyl group, or a perfluoroalkylaryl group, perfluoro optionally containing one or more oxygen, nitrogen, or sulfur atoms in its chain It is an aryl group and -O- perfluoroaryl group.

In addition, the present invention provides a polyphenylene-based anion-exchange polymer, which is prepared by ion exchange reaction of the halogenated polyphenylene-based polymer and has a chemical structure of the formula (5).

<Formula 5>

In Formula 5, m 'and n are positive integers, m''is 0 or a positive integer, and 0.1 ≦ n / (m' + m '') ≤ 100, and 0≤ m '' / m ' ≤ 100, A ₁ and A ₂ may be the same or different from each other, which is-(C = O)-, -P (= O)-, -CF _2- , -C as a single bond or electron drawer. (CF ₃ ) ₂ -and SO _2- , and Z is an ion exchange functional group in an amine group, ammonium group, amino group, imine group, sulfonium group, phosphonium group, pyridyl group, carbazolyl group and imidazolyl group Any one of an anion exchange functional group selected or an anion exchange functional group in a salt state thereof, an amphoteric ion exchange functional group selected from betaine and a sulfobetaine and an ion exchange group selected from a combination thereof or an anion exchange functional group in a salt state thereof and, R _1, R _2, R _3, R ₄ and R ₅ are both hydrogen atoms or at least one fluorine atom, an aryl group, a perfluoroalkyl roal Group or, alternatively perfluoroalkyl containing one or more oxygen, nitrogen, or sulfur atom in its chain alkylaryl group, a perfluoroalkyl group and an aryl -O- group aryl perfluoroalkyl.

In addition, the present invention is a polymerizing step of preparing a polyphenylene-based polymer by copolymerization of the hydrophilic unit monomer of the formula (1) and the hydrophobic unit monomer of the formula (2);

<Formula 1>

 <Formula 2>

(In Formula 1 and Formula 2, A ₁ and A ₂ may be the same as or different from each other, and as a single bond or an electron drawer,-(C = O)-, -P (= O)-, -CF _2- , -C (CF ₃ ) ₂ -and SO _2- , X is any one of chlorine (Cl), bromine (Br) or iodine (I), R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are both hydrogen atoms or at least one fluorine atom, aryl group, perfluoroalkyl group, or a perfluoroalkylaryl group optionally containing at least one oxygen, nitrogen, or sulfur atom in its chain, Perfluoroaryl group and -O- perfluoroaryl group.)

A halogenation step of halogenating the prepared polyphenylene polymer to produce a halogenated polyphenylene polymer; And

It provides a method for producing a polyphenylene-based anion-exchange polymer, characterized in that it comprises an ion exchange step of producing a polyphenylene-based anion-exchange polymer to the halogenated polyphenylene-based polymer through an ion exchange reaction.

In the method for producing a polyphenylene-based anion exchange polymer according to the present invention, the halogenation step may be a bromination reaction, the ion exchange step is an amine group, ammonium group, amino group, imine group, sulfonium group, In the anion exchange functional group selected from phosphonium group, pyridyl group, carbazolyl group and imidazolyl group or anion exchange functional group in salt state thereof, amphoteric ion exchange functional group selected from betaine and sulfobetaine and combinations thereof It may be to introduce any one of an ion exchange group selected or an anion exchange functional group in a salt state thereof.

In addition, the present invention is a method for using a membrane prepared by complexing the polyphenylene-based anion exchange polymer itself prepared by the production method or a polyphenylene-based anion-exchange polymer complex with a support for the separator for redox flow battery, It provides a redox flow battery comprising the separator and the positive electrode, the positive electrode electrolyte, the negative electrode electrolyte and the negative electrode.

 The redox flow battery according to the present invention may be a vanadium-based redox flow battery, a polysulfide bromine (PSB) redox flow battery, or a zinc-bromine (Zn-Br) redox flow battery.

As described above, the polyphenylene-based anion exchange polymer according to the present invention is structurally composed of polyphenylene, and the main chain of the electron donor properties such as -O-, -S-,-(CH ₂ ) _n -in the main chain. It is composed of only CC bonds between benzene rings and does not include a linking group, so the dimensional stability of the material is excellent, and the crossover of the active material is lower than that of commercially available Nafion115 (cation exchange material), and thus the coulombic efficiency is improved. have.

In addition, the polyphenylene-based anion exchange polymer according to the present invention is a redox flow battery, fuel cell (fuel cell), electrodialysis (ED), reverse electrodialysis (RED), capacitive deionization; CDI is very useful in such fields.

Figure 1 shows a simplified redox flow battery having a polyphenylene-based anion exchange material as a separator according to an embodiment of the present invention.

Figure 2 shows the chemical structure and ¹ H-NMR of the monomer used in the preparation of the polyphenylene-based polymer according to an embodiment of the present invention.

3 is a polyphenylene-based polymer prepared according to one embodiment of the present invention (P1: PPP-1 / 1, halogenated polyphenylene-based polymer (P2: BrPPP-1 / 1) and polyphenylene-based anion exchange polymer (P3: The chemical structure and ¹ H-NMR of QPPP-1 / 1) are shown.

Figure 4 shows the mechanical strength of the polyphenylene-based anion exchange material prepared according to an embodiment of the present invention in comparison with Nafion115.

Figure 5 shows the numerical stability of the polyphenylene-based anion exchange material prepared according to an embodiment of the present invention in comparison with Nafion115.

Figure 6 shows the thermal stability of the polyphenylene-based anion exchange material prepared according to an embodiment of the present invention.

Figure 7 shows the result of comparing the ion conductivity of the polyphenylene-based anion exchange material prepared according to an embodiment of the present invention.

Figure 8 shows the vanadium ion permeability results of the polyphenylene-based anion exchange material prepared according to an embodiment of the present invention.

Figure 9a is a comparison of the VRFB efficiency according to the current density of the polyphenylene-based anion exchange material (QPPP-1 / 1) prepared according to an embodiment of the present invention.

Figure 9b is a comparison of the VRFB efficiency according to the current density of the polyphenylene-based anion exchange material (QPPP-1 / 1) prepared according to an embodiment of the present invention.

Figure 9c is a comparison of the VRFB efficiency according to the current density of the polyphenylene-based anion exchange material (QPPP-1 / 1) prepared according to an embodiment of the present invention.

Figure 10a is a comparison of the VRFB efficiency according to the current density of the polyphenylene-based anion exchange material (QPPP-1 / 2) prepared according to an embodiment of the present invention.

Figure 10b is a comparison of the VRFB efficiency according to the current density of the polyphenylene-based anion exchange material (QPPP-1 / 2) prepared according to an embodiment of the present invention.

Figure 10c is a comparison of the VRFB efficiency according to the current density of the polyphenylene-based anion exchange material (QPPP-1 / 2) prepared according to an embodiment of the present invention.

Hereinafter, the present invention will be described in detail. The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best explain their invention in the best way possible. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

1 is a view briefly showing a redox flow battery having a separator structure of the present invention.

As shown in FIG. 1, a cell housing 51 having a predetermined size as its component, an ion exchange membrane 11 provided across a center of the cell housing 51, and an ion exchange membrane 11 of the ion exchange membrane 11 are formed. The inner left of the separated cell housing 51. Inlets 31 and 41 formed on both sides of the anode 21 and the cathode 22, respectively, on the upper and lower ends of the cell housing 51 to perform the inflow and outflow of the electrolyte used for the respective electrodes. And outlets 32 and 42 are provided. The positive electrode 21 and the negative electrode 22 include carbon felt, carbon nonwoven fabric, graphite felt, graphite plate, and the like, which are conventional materials.

The reaction mechanism of the redox flow battery is made by the oxidation / reduction reaction of the positive electrode 21 and the negative electrode 22, and the positive electrode electrolyte and the negative electrode electrolyte for causing the above reaction are stored in separate storage tanks (not shown). Are stored in the cell housing 51 and introduced into the cell housing 51 through the electrolyte inlets 31 and 41 formed in the cell housing 51, respectively, to react with the positive electrode 21 and the negative electrode 22 to react with each other. It has a circulation system that flows out through the electrolyte outlet (32, 42).

Redox flow battery of the present invention having the configuration as described above using the V (IV) / V (V) redox couple as the cathode electrolyte, and V (II) / V (III) redox couple as the cathode electrolyte It can be applied to all vanadium-based redox flow battery.

 In addition, the redox flow battery of the present invention having the configuration described above uses a halogen redox couple as the cathode electrolyte, and an all-vanadium redox flow using the V (II) / V (III) redox couple as the cathode electrolyte. It can be applied to a battery.

 In addition, the redox flow battery of the present invention having the configuration as described above is a polysulfide bromine (PSB) redox flow battery using a halogen redox couple as a cathode electrolyte, sulfide redox couple as a cathode electrolyte Can be applied.

 In addition, the redox flow battery of the present invention having the configuration as described above using a halogen redox couple as the cathode electrolyte, zinc-bromine (Zn-Br) redox using a zinc (Zn) redox couple as the cathode electrolyte It can be applied to flow cells.

In general, as the ion exchange membrane 11, a Nafion cation exchange membrane, a cation exchange membrane having a sulfonic acid group or a carboxylic acid group, an anion exchange membrane having an ammonium group or a phosphonium group, or the like used in a conventional redox flow battery has been used.

The present invention is characterized in that the polyphenylene-based anion exchange polymer as an ion exchange membrane. In addition, reinforcing composite membranes prepared by impregnating an ion conductor in a nanoweb support for improving long-term durability by reducing the rate of dimensional change can be used as an ion exchange membrane.As a nanoweb support, polyimide, polymethylpentene, polyester , Polyacrylonitrile, polyvinylamide, polypropylene, polyvinyl fluoride may be used, but is not limited thereto.

Method for producing a polyphenylene-based anion exchange material according to the present invention can be prepared according to the following Scheme 1.

<Scheme 1>

Preparation Example 1 Synthesis of Polymer (PPP-n / m: Preparation of P1)

Polymer synthesis process of polyphenylene is as follows. Prepare completely dried flasks with 2,5-dichloro-4'-methylbenzophenone (M1) (5.28 g), 2,5-dichlorobenzophenone (M2) (5 g), Ni (pph ₃ ) ₂ Cl ₂ (0.78 g), NaI (0.72g), triphenylphosphine (3.76g) and Zn (3.2g) were dissolved in dimethylacetamide (DMAc) (80ml), stirred at 80 ° C for about 3h, and cooled to room temperature. Poured into ethanol / hydrochloric acid (9: 1, v: v) to remove Zn and washed with hot ethanol and hot distilled water, the synthesized polymer was dried under vacuum at 80 ℃ to obtain a P1 polymer. The synthesized polymer P1 was analyzed by ¹ H-NMR spectroscopy, and the polymer synthesis was confirmed by comparing the number of aromatic hydrogens and aliphatic protons.

The chemical formula and ¹ H NMR of M1 and M2 used to synthesize P1 polymer are shown in FIG. 2, and the chemical structure and ¹ H NMR of P1 polymer are shown in FIG. 3.

Preparation Example 2 Bromination (BrPPP-n / m: Preparation of P2)

The bromination process of polyphenylene is as follows. 1 g of the P1 polymer prepared according to Preparation Example 1 was completely dissolved in 20 ml of 1,1,2,2-tetrachloroethane (1,1,2,2-tetrachloroethane), followed by 0.05 g of benzoyl peroxide (BPO) and N. 0.5673 g of -bromosuccinimide (NBS) was added and reacted at 90 ° C. for 3.5 hours. The reaction mixture was precipitated in excess methanol, washed several times with methanol and distilled water, and washed with P2 at 80 ° C. for 24 hours. Dried in vacuo. When analyzed by ¹ H-NMR spectroscopy, halogen functional groups were observed at 4.5 ppm and the degree of bromination of polyphenylene in the present example was 0.75.

The chemical formula and ¹ H NMR of the prepared P2 polymer are shown in FIG. 3.

Preparation Example 3 Ion Exchange Reaction (QPPP-n / m: Preparation of P3)

The anion exchange functional group substitution of the bromomethyl functional group is as follows. The P2 polymer prepared in Preparation Example 2 having a halogen substituent was dissolved in dimethyl sulfoxide (DMSO) solution at 4wt%, and then trimethylamine or methylimidazole was dissolved in a solution containing P2 polymer. Slowly added and precipitated in tertiary distilled water after 24 hours. Wherein trimethylamine is ˜45 wt. % Aqueous solution was used. The prepared anion-exchange functional group-substituted polyphenylene-based membrane is hereinafter referred to as QPPP-n / m (P3), where n and m represent molar ratios of the hydrophobic portion and the hydrophilic portion, respectively.

The chemical structure and ¹ H NMR of the prepared P3 polymer are shown in FIG. 3.

<Evaluation of Polyphenylene-based Anion Exchange Material>

(1) dimensional stability evaluation

Figure 4 shows the mechanical strength of the polyphenylene-based anion exchange material prepared according to an embodiment of the present invention compared to Nafion115, Figure 5 shows the numerical stability comparison results. As can be seen in Figure 4 QPPP-1 / 1 and QPPP-1 / 2 according to an embodiment of the present invention not only shows a very good tensile strength (tensile strangth) compared to the commercial material Nafion 115 can be seen in Figure 5 As can be seen, QPPP-1 / 1 and QPPP-1 / 2 show lower dimensional stability than Nafion 115, which is used despite the large ion exchange capacity. It can be seen that the results are very stable at about 50%.

The ion exchange performance (IEC) of the ion exchange membrane prepared according to the above preparation was measured after changing to Cl ^- to OH ^- in an aqueous 1M NaOH solution for 24 hours at room temperature, and the sample substituted with OH ^- 0.01M HCl aqueous solution After stirring for 24 hours, the acid-base was titrated with 0.01 M NaOH aqueous solution.

Dimensional stability was measured at room temperature by weight, length, thickness, volume change in the wet state and dry state of the ion exchange membrane and summarized the results in Table 1 below.

Polymer	Inherent viscosity (dl / g)	DB 1) (%)	IECw t 2) (meq./g)	IECw (meq./g)	Water uptake (wt%, R.T.)	Dimension Changes (%, 25 ℃)
						Δl	Δt	Δt / Δl	ΔV
QPPP-1 / 1	3.4	75	2.1	1.6	20	4.5	6.5	0.7	16
QPPP-1 / 2	3.3	75	2.7	2.0	22	6.7	17.3	2.6	33

1) degree of bromination, 2) theoretical IEC

As shown in Table 1, it was confirmed by measuring the viscosity (inherent viscosity) that the main chain of the synthesized anion exchange material synthesized at a high molecular weight, the synthesized anion exchange material showed the same degree of bromination, the prepared anion exchange As the material increases, the change of moisture content and numerical value increases with the increase of IEC.

Figure 6 shows the thermal stability of the polyphenylene-based anion exchange material prepared according to an embodiment of the present invention. Dynamic mechanical analysis (DMA) analysis was performed to confirm the rheological behavior of the developed material. As can be seen in Figure 6 QPPP-1 / 1 and QPPP-1 / 2 according to an embodiment of the present invention storage modulus (Storage modulus) up to about 200 ℃ is very large, respectively more than 3GPa, 4GPa, which is the strength of the material It can be seen that it is not only excellent but also easy to handle in the process even with a thin thickness, and also the glass transition temperature is very stable thermally at 230 ° C. or higher.

(2) ionic conductivity evaluation

Ion conductivity was measured by 4-probe electrochemical impedance spectroscopy (Solatron 1280) using a Pt electrode cell. After this time, ion exchange membranes, each carrying 24 hours in 1M NaCl aqueous solution, 1M Na ₂ SO ₄ aqueous solution of Cl ^-, SO ₄ ^2- ion conductivity was measured, measurement conditions are 25 ℃, 40 ℃ at 100% relative humidity, 60 The measurement at ℃, 70 ℃, 80 ℃ was summarized in Table 2 below.

Figure 7 shows the result of comparing the ion conductivity of the polyphenylene-based anion exchange material prepared according to an embodiment of the present invention. As can be seen in Figure 7, QPPP-1 / 1 and QPPP-1 / 2 according to an embodiment of the present invention shows excellent anion conductivity, this anion conductivity is improved with the increase of temperature due to the excellent dimensional stability One result.

Polymer	Ion conductivity (mS cm -1 )
	25 ℃		40 ℃		60 ℃		70 ℃		80 ℃
	Cl -	SO 4 2-	Cl -	SO 4 2-	Cl -	SO 4 2-	Cl -	SO 4 2-	Cl -	SO 4 2-
QPPP-1 / 1	3	2.6	4	3.7	6	5.7	10	8.2	14	10
QPPP-1 / 2	5.5	3	7	3.7	11	8	17	11	20	15

As shown in Table 2, and because the moving speed of the ions increases as the temperature increases, which in the ionic conductivity increases as the temperature of each membrane is increased, ionic conductivity is Cl ^-, and reduced to, SO ₄ ^2- sequence It can be seen that this is related to the size of the ion and the rate of migration.

(3) Vanadium ion permeability evaluation

Vanadium ion permeability was measured by drying the ion exchange membrane in 1M Na ₂ SO ₄ aqueous solution for 24 hours and then drying. By the 3M H ₂ SO ₄ aqueous solution as a solvent 2M MgSO ₄ solution and 3M H ₂ SO ₄ aqueous solution and the solvent A 2M VOSO _4, while with the ion exchange membrane circulating the solution between an aqueous solution, the concentration of vanadium ions in time UV-visible to the It was measured by spectroscopy (Agilent cary 8454). Nafion115 was used for 24 hours in 1.5MH ₂ SO ₄ aqueous solution, washed in 3 distilled water, and dried for 24 hours. The results are summarized in Table 3 below.

Figure 8 shows the vanadium ion permeability results of the polyphenylene-based anion exchange material prepared according to an embodiment of the present invention. As can be seen in Figure 8, QPPP-1 / 2 according to the present invention shows a very low vanadium permeability, because vanadium is used as the active material in the vanadium redox flow battery, high vanadium permeability is due to a decrease in capacity and battery efficiency As a result, low vanadium permeability is a very important factor for improving the capacity as well as the efficiency of the battery. As shown in FIG. 8, QPPP-1 / 2 has a very low vanadium permeability of about 1/1000 as compared to Nafion 115.

Polymer	Vanadium ion permeability (cm 2 / min)
QPPP-1 / 1	Not detected
QPPP-1 / 2	2.12 x 10 -9
Nafion 115	2.88 x 10 -6

As shown in Table 3, the prepared polyphenylene-based anion exchange membrane showed very low vanadium ion permeability compared to Nafion115, and only the anion exchange membrane having a high IEC showed vanadium ion permeability and had QPPP-1 / 1 (having low IEC). Vanadium ion permeation was not measured for 200 hours.

(4) Redox Flow Battery Performance Evaluation

A vanadium redox flow battery unit cell performance evaluation of the ion exchange membrane was performed.

The ion exchange membrane was used after drying in 1M Na ₂ SO ₄ aqueous solution for 24 hours, and was evaluated by WonATech battery test system. At this time, the effective area of the ion exchange membrane was 49 ㎠, current density 50 -200 mA cm ^-2 , Performance evaluation was performed at a flow rate of 100 ml min ^{- 1} , and Nafion115 was used after washing for 24 hours in 1.5MH ₂ SO ₄ aqueous solution and washing with 3 distilled water and drying for 24 hours, and the evaluation results are summarized in Table 4 below. It was.

9A, 9B and 9C are shown to compare the VRFB efficiency according to the current density of the polyphenylene-based anion exchange material (QPPP-1 / 1) prepared according to an embodiment of the present invention, Figures 10a, 10b and 10c It is shown by comparing the VRFB efficiency according to the current density of the polyphenylene-based anion exchange material (QPPP-1 / 2) prepared according to an embodiment of the present invention. As can be seen in Figures 9a to 9c and 10a to 10c QPPP-1 / 1 and QPPP-1 / 2 according to an embodiment of the present invention shows excellent battery efficiency, in particular QPPP as can be seen in Figures 10a to 10c -1/2 showed very good CE of nearly 100% even when charged and discharged at various current densities, and showed very good VE equivalent to that of Nafion, showing better energy efficiency than commercially available Nafion 115. Able to know. In particular, it shows stable cell efficiency even at 100 cycles of operation, and very good cell efficiency of more than 85% even at 80 mA / cm ² .

Polymer	C.E.	V.E.	E.E	Vanadium ion permeability (cm 2 / min)
QPPP-1 / 1	99	80	80	Not detected
QPPP-1 / 2	98	90.5-91.5	88-89	2.12 x 10 -9
Nafion 115	95.8	90.5	86.6	2.88 x 10 -6

CE = t _d t _c × 100%

VE = V _d V _c × 100%

E.E. = C.E x V.E.

t _d is the discharge time, t _c is the charge time, V _d is the discharge voltage, V _c is the charge voltage

As shown in Table 4, the Coulombic efficiency (CE) is higher overall cross-linked anion exchange membrane than Nafion115, which is due to the low vanadium ion permeability, the voltage for the manufactured anion exchange material QPPP-1 / 2 Voltage efficiency (VE) and energy efficiency (EE) were equal to or better than Nafion115. That is, it can be seen that the polyphenylene-based anion exchanger QPPP-n / m shows better charge / discharge capacity retention than that of Nafion115.

Specific configuration of a single cell is as follows. For the anode and cathode materials, 5mm thick carbon felt was heat treated and treated with acid. Bipolar plates, electrode frames, and end plates were made of standard energy unit cells. V (IV) / V ( V) Using a redox couple, using a V (II) / V (III) redox couple as the cathode electrolyte, cut the 35 μm thick ion exchange membrane into horizontal and vertical 100 mm × 100 mm sizes as shown in FIG. 1. The charge and discharge test and the efficiency of the cell were measured by mounting the fabricated single cell.

Single cells were run tested at room temperature (25 ° C.). The flow rate of the electrolyte was fixed at 100 ml / min, up to 1.6 V at a current density of 50 to 200 mA / cm ² during charging, and up to 1.0 V at a current density of 50 to 200 mA / cm ² during discharge. All single cells were repeatedly charged and discharged 30 times for durability test.

Claims (10)

1. A polymer prepared by copolymerization of a hydrophilic unit monomer of Formula 1 with a hydrophobic unit monomer of Formula 2:

   <Formula 1>

   

    <Formula 2>

   

   In Formula 1 and Formula 2, A ₁ and A ₂ may be the same as or different from each other, which is a single bond or-(C = O)-, -P (= O)-, -CF _2- , -C (CF ₃ ) any one selected from ₂ -and SO _2- , X is any one of chlorine (Cl), bromine (Br) or iodine (I), and R ₁ , R ₂ , R ₃ , R ₄ and R ₅ Are all hydrogen atoms or at least one fluorine atom, aryl group, perfluoroalkyl group, or a perfluoroalkylaryl group, perfluoroaryl optionally containing one or more oxygen, nitrogen, or sulfur atoms in its chain Group and -O- perfluoroaryl group.
2. The method according to claim 1,

   The polymer is a polymer characterized in that it has a chemical structure of the formula

   <Formula 3>

   

   In Formula 3, m and n are positive integers ranging from 0.1 ≦ n / m ≦ 100, and A ₁ and A ₂ may be the same as or different from each other, which may be a single bond or-(C = O)-,- P (= O)-, -CF _2- , -C (CF ₃ ) ₂ -and SO _2- , wherein R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are all hydrogen atoms or At least one fluorine atom, aryl group, perfluoroalkyl group, or optionally a perfluoroalkylaryl group, perfluoroaryl group and -O- purple containing one or more oxygen, nitrogen, or sulfur atoms in the chain Luoroaryl group.
3. Halogenated polymer, characterized in that having the chemical structure of formula

   <Formula 4>

   

   In Formula 4, m 'and n are positive integers, m''is 0 or a positive integer, and 0.1 ≦ n / (m' + m '') ≤ 100, and 0≤ m '' / m ' ≤ 100, A ₁ and A ₂ may be the same or different from each other, which is a single bond or-(C = O)-, -P (= O)-, -CF _2- , -C (CF ₃ ) Any one selected from ₂ -and SO _2- , W is any one of chlorine (Cl), bromine (Br) or iodine (I), and R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are all hydrogen An atom or at least one fluorine atom, an aryl group, a perfluoroalkyl group, or optionally a perfluoroalkylaryl group, perfluoroaryl group containing one or more oxygen, nitrogen, or sulfur atoms in the chain; and O-perfluoroaryl group.
4. Anion exchange polymer, characterized in that having a chemical structure of the formula

   <Formula 5>

   

   In Formula 5, m 'and n are positive integers, m''is 0 or a positive integer, and 0.1 ≦ n / (m' + m '') ≤ 100, and 0≤ m '' / m ' ≤ 100, A ₁ and A ₂ may be the same or different from each other, which is a single bond or-(C = O)-, -P (= O)-, -CF _2- , -C (CF ₃ ) ₂ -and SO _2- , Z is an anion exchange functional group selected from ammonium group, amino group, imine group, sulfonium group, phosphonium group, pyridyl group, carbazolyl group and imidazolyl group or salt thereof Any one of an anion exchange functional group, an amphoteric ion exchange functional group selected from betaine and a sulfobetaine and an ion exchange group selected from a combination thereof, or an anion exchange functional group in a salt state thereof, and R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are both hydrogen atoms or at least one fluorine atom, an aryl group, or a perfluoroalkyl group, optionally one or more of its chain In cattle, nitrogen, or alkylaryl group perfluoroalkyl containing a sulfur atom, a perfluoroalkyl group and an aryl -O- perfluoroalkyl an aryl group.
5. A polymerization reaction step of preparing a polyphenylene-based polymer by copolymerization of a hydrophilic unit monomer of Formula 1 with a hydrophobic unit monomer of Formula 2;

   <Formula 1>

   

   <Formula 2>

   

   In Formula 1 and Formula 2, A ₁ and A ₂ may be the same as or different from each other, which is a single bond or-(C = O)-, -P (= O)-, -CF _2- , -C (CF ₃ ) any one selected from ₂ -and SO _2- , X is any one of chlorine (Cl), bromine (Br) or iodine (I), and R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are All are hydrogen atoms or at least one fluorine atom, aryl group, perfluoroalkyl group, or a perfluoroalkylaryl group, perfluoroaryl group optionally containing one or more oxygen, nitrogen, or sulfur atoms in its chain And -O- perfluoroaryl group

   A halogenation step of halogenating the prepared polyphenylene polymer to produce a halogenated polyphenylene polymer; And

   Method for producing a polyphenylene-based anion exchange polymer, characterized in that it comprises an ion exchange step of producing a polyphenylene-based anion exchange polymer through the halogenated polyphenylene-based polymer through an ion exchange reaction.
6. The method according to claim 5,

   The halogenation step is a method for producing a polyphenylene-based anion exchange polymer, characterized in that using a bromination reaction.
7. The method according to claim 5,

   The ion exchange step is an anion exchange functional group selected from ammonium group, amino group, imine group, sulfonium group, phosphonium group, pyridyl group, carbazolyl group and imidazolyl group as an ion exchange functional group, or anion exchange functional group in the salt state thereof, beta A process for producing a polyphenylene-based anion exchange polymer, characterized in that any one of an amphoteric ion exchange functional group selected from phosphorus and sulfobetaine and an ion exchange group selected from a combination thereof or an anion exchange functional group in a salt state thereof is introduced. .
8. A separator membrane for redox flow batteries, characterized in that the polymer membrane formed by molding the polyphenylene-based anion exchange polymer itself according to claim 4 or a composite membrane prepared by complexing a polyphenylene-based anion exchange polymer with a support.
9. A redox flow battery comprising the separator according to claim 8 and a positive electrode, a positive electrode electrolyte, a negative electrode electrolyte and a negative electrode.
10. The method according to claim 9,

    The battery is any one of a vanadium-based redox flow battery, polysulfidebromine (PSB) redox flow battery, or zinc-bromine (Zn-Br) redox flow battery.

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