KR102026509B1 - Compound, polymer using the same, polymer electrolyte membrane using the same - Google Patents

Abstract

The present specification relates to a compound of Chemical Formula 1, a polymer using the same, a polymer electrolyte membrane using the same, a fuel cell using the same, and a redox flow battery including the same.

Description

Compound, Polymer Using the Same and Electrolyte Membrane Using the Same {COMPOUND, POLYMER USING THE SAME, POLYMER ELECTROLYTE MEMBRANE USING THE SAME}

The present specification relates to a compound, a polymer using the same, a polymer electrolyte membrane using the same, a fuel cell including the same, and a redox flow cell including the same.

A polymer is a compound having a large molecular weight, and refers to a compound formed by polymerizing several low molecules called monomers. Polymers can be classified into linear polymers, branched polymers, cross-linked polymers, etc. according to the structure and shape of the chain, and show significant differences in physical and chemical properties.

The polymer has been mainly used as a structural material having excellent mechanical strength and good workability compared to a relatively light weight, but recently, it has been used as a functional material due to its excellent physical and chemical properties.

A representative example is the use as a polymer membrane. The polymer membrane is not a simple thin membrane such as a film, but means a polymer membrane having a function of separating substances. Specifically, it is used as an electrolyte membrane capable of cation exchange such as fuel cells and redox flow batteries.

A fuel cell is an energy conversion device that converts chemical energy of a fuel directly into electrical energy. In other words, a fuel cell is a power generation method that uses fuel gas and an oxidant and generates electric power by using electrons generated during the redox reaction. The membrane electrode assembly (MEA) of a fuel cell is a portion in which an electrochemical reaction between hydrogen and oxygen occurs and is composed of a cathode, an anode, and an electrolyte membrane, that is, an ion conductive electrolyte membrane.

A redox flow battery (redox flow battery) is an electrochemical storage device that stores the chemical energy of an active material directly as electrical energy by charging and discharging the active material contained in the electrolyte. to be. The unit cell of the redox flow battery includes an electrode, an electrolyte, and an ion exchange membrane (electrolyte membrane).

Fuel cells and redox flow cells are being researched and developed as next generation energy sources due to their high energy efficiency and eco-friendly features with low emissions.

One of the key components in fuel cells and redox flow cells is a polymer electrolyte membrane capable of cation exchange, 1) excellent proton conductivity 2) prevention of crossover of electrolyte, 3) strong chemical resistance, 4) mechanical properties And / or 4) low swelling ratio.

The polymer electrolyte membrane is classified into fluorine-based, partially fluorine-based, hydrocarbon-based, and the like, and the partial fluorine-based polymer electrolyte membrane has a fluorine-based main chain, and thus, has excellent physical and chemical stability and high thermal stability. In addition, as in the fluorine-based polymer electrolyte membrane, the partial fluorine-based polymer electrolyte membrane has a cation transfer functional group attached to the end of the fluorine-based chain, and thus has the advantages of a hydrocarbon-based polymer electrolyte membrane and a fluorine-based polymer electrolyte membrane.

Research into monomers used in the synthesis of polymers for producing polymer membranes for fuel cells and / or redox flow batteries having high durability and acid resistance has been made. In addition, in order to increase the utilization of the partial fluorine-based polymer electrolyte membrane, research on the partial fluorine-based polymer electrolyte membrane with improved proton conductivity, mechanical properties, physical chemical properties, etc. has been conducted.

Republic of Korea Publication No. 2003-0076057

The present specification provides a compound, a polymer using the same, a polymer electrolyte membrane using the same, a fuel cell including the same, and a redox flow cell including the same.

An exemplary embodiment of the present specification provides a compound represented by Formula 1:

[Formula 1]

In Chemical Formula 1,

A1 and A2 are the same as or different from each other, and are each independently selected from the group consisting of F, Cl, Br and NO ₂ ,

B1 to B3 are the same as or different from each other, and each independently selected from the group consisting of CO, S, SO and SO ₂ ,

C1 and C2 are the same as or different from each other, and are each independently represented by the following formula (2),

[Formula 2]

In Formula 2, M is hydrogen or an alkali metal ion,

g is 0 or 1, h is 0 or 1, i and j are integers from 2 to 6,

R ₁ to R ₄ are the same as or different from each other, and each independently hydrogen; heavy hydrogen; Halogen group; Or a substituted or unsubstituted alkyl group,

a and b are integers of 0 or 1, c and f are integers of 1 to 4, d and e are integers of 1 to 3, and when c to f are 2 or more, the substituents in parentheses are the same or different from each other.

In addition, an exemplary embodiment of the present specification provides a polymer including a monomer derived from the compound represented by Chemical Formula 1.

In addition, the present disclosure provides a polymer electrolyte membrane including the polymer described above.

The present specification is an anode; Cathode; And it provides a membrane-electrode assembly comprising the above-described polymer electrolyte membrane provided between the anode and the cathode.

The present specification includes two or more of the aforementioned membrane-electrode assemblies; A stack comprising a bipolar plate provided between the membrane-electrode assemblies; A fuel supply unit supplying fuel to the stack; And it provides a polymer electrolyte fuel cell comprising an oxidant supply unit for supplying an oxidant to the stack.

Finally, the present specification is a positive electrode cell comprising a positive electrode and a positive electrode electrolyte; A cathode cell comprising a cathode and a cathode electrolyte; And it provides a redox flow battery comprising the above-described polymer electrolyte membrane provided between the cathode cell and the anode cell.

The polymer synthesized using the compound according to one embodiment of the present specification has excellent durability and acid resistance.

Compound according to an exemplary embodiment of the present disclosure to increase the proton conductivity by introducing a partial fluorine-based sulfonic acid to the hydrocarbon main chain to reduce the pKa value, in particular, the C is the reaction site of the main chain ( The distance between the site and the site of the sulfonic acid group giving the ion transfer effect is increased, and the phase separation performance of the electrolyte membrane is improved due to the effect of π-π stacking of a plurality of phenyl linkage groups.

A polymer electrolyte membrane including a polymer according to one embodiment of the present specification easily forms a hydrophilic-hydrophobic phase separation structure.

In addition, the polymer electrolyte membrane effectively forms a hydrophilic channel in the polymer electrolyte membrane by controlling the phase separation structure.

In addition, the polymer electrolyte membrane has excellent proton conductivity. The result is a high performance of fuel cells and / or redox flow cells comprising the same.

1 is a schematic diagram illustrating a principle of electricity generation of a fuel cell.
2 is a view schematically showing an embodiment of a redox flow battery.
3 is a view schematically showing an embodiment of a fuel cell.

Hereinafter, the present specification will be described in more detail.

As used herein, the term "substituted or unsubstituted" is deuterium; Halogen group; Or one or more substituents selected from the group consisting of alkoxy groups, or no substituent.

An exemplary embodiment of the present specification provides a polymer including a monomer derived from the compound represented by Chemical Formula 1.

As used herein, "monomer" refers to a structure in which a compound is included in a divalent or more form in a polymer by a polymerization reaction.

In the present specification, when a part "contains" a certain component, this means that the component may further include other components, except for the case where there is no contrary description.

In the present specification, the "derived" means that the bonding of the compound is broken, or the substituent is separated, a new bond occurs, the unit derived from the compound may mean a unit connected to the main chain of the polymer. The unit may be included in the main chain in the polymer to constitute the polymer.

In one embodiment of the present specification, the compound of Formula 1 is represented by Formula 1-1 and 1-2:

[Formula 1-1]

[Formula 1-2]

The definitions of A1, A2, B1 to B3, C1 C2, R1 to R4, and c to f of Chemical Formulas 1-1 and 1-2 are the same as those of Chemical Formula 1.

In the present specification, A1 and A2 are substituted with B and para, and when A1 and A2 are B and a meta position, A1 or A1 at a meta position of B which is an electron-withdrawing group. When A2 is present, it is inactivated (Deactivating) to decrease the reactivity, when present in the ortho position, it is difficult to obtain a high molecular weight material due to the difference in reactivity between A1 and A2. Therefore, when A1 and A2 are substituted with B and para, reactivity is improved, and a high molecular weight material can be obtained.

In one embodiment of the present specification, A1 and A2 are F.

In one embodiment of the present specification, B is SO ₂ .

In one embodiment of the present specification, Chemical Formula 2 is

이고, M은 수소 또는 알칼리금속이다.CF ₂ CF ₂ OCF ₂ CF ₂ SO ₃ M or

And M is hydrogen or an alkali metal.

In one embodiment of the present specification, the alkali metal is an element belonging to Group 1 of the periodic table.

In one embodiment of the present specification, the alkali metal is selected from the group consisting of Li, Na, and K.

In one embodiment of the present specification, the alkali metal is K.

이다.In one embodiment of the present specification, C1 and C2 are

to be.

이다.In one embodiment of the present specification, C1 and C2 are

to be.

이다.In one embodiment of the present specification, C1 and C2 are

to be.

이다.In one embodiment of the present specification, C1 and C2 are

to be.

In the present specification, the C1 and C2 in the general formula (1) have an electron withdrawing character, so that the formation of a high molecular weight polymer is easy, and there is an advantage of providing a stable polymer.

In one embodiment of the present specification, R ₁ to R ₄ hydrogen.

In one embodiment of the present specification, the compound represented by Chemical Formula 1 is represented by any one of the following chemical formulas.

In one embodiment of the present specification, a method of preparing the polymer may be prepared by a method known in the art, and specifically, the polymer may be prepared by a nucleophilic substitution reaction method. It is polymerized by the nucleophilic substitution reaction of A1 or A2 with a diol or dithiol monomer of the present invention, and finally, poly (arylene ether) or poly (aryl It may be prepared from ethylene thioether (Poly).

In one embodiment of the present specification, the polymer includes 50 mol% to 60 mol% of monomers derived from the compound represented by Chemical Formula 1, based on a total of 100 mol% of monomers constituting the polymer. In one embodiment of the present specification, the polymer includes only the monomer represented by Chemical Formula 1.

A monomer derived from the compound may be understood by those skilled in the art to mean a state in which the compound is bonded to the main chain or the side chain in the polymer by a polymerization reaction for the polymer material.

In another exemplary embodiment, the polymer may further include another second monomer in addition to the monomer derived from the compound represented by Chemical Formula 1. In one embodiment of the present specification, when the polymer further includes a second monomer, the content of the monomer derived from the compound represented by Formula 1 is preferably 30 mol% to 70 mol%.

The monomer derived from the compound represented by Formula 1 according to one embodiment of the present specification serves to control the ionic conductivity of the separator.

According to another exemplary embodiment, the second monomer may be selected from units for improving the mechanical strength of the polymer, and any monomer capable of improving the mechanical strength is not limited thereto.

In one embodiment of the present specification, the second monomer may be selected from the following structural formulas, but is not limited to the following structural formulas.

,

,

,

,

 In one embodiment of the present specification, the weight average molecular weight of the polymer is 500 g / mol to 2,000,000 g / mol. When the weight average molecular weight of the polymer is in the above range, the mechanical properties of the electrolyte membrane including the polymer are not lowered, and the solubility of the polymer may be maintained to facilitate the preparation of the electrolyte membrane.

In one embodiment of the present specification, the polymer including the unit derived from the compound is a random polymer or a block polymer.

In one embodiment of the present specification, the monomer derived from the compound represented by Formula 1 and the second monomer may constitute a random polymer.

In one embodiment of the present specification, the polymer may be a block polymer. More specifically, the block polymer may include a hydrophilic block and a hydrophobic block, and the hydrophilic block may include a monomer derived from the compound.

In one embodiment of the present specification, the hydrophilic block and the hydrophobic block are included in the block polymer at a molar ratio of 1: 0.1 to 1:10. In one embodiment of the present specification, the hydrophilic block and the hydrophobic block are included in the block polymer in a molar ratio of 1: 0 to 1: 2.

In an exemplary embodiment of the present specification, the monomer derived from the compound represented by Formula 1 in the hydrophilic block is included 30 mol% to 70 mol% based on the hydrophilic block.

In one embodiment of the present specification, the number average molecular weight of the hydrophilic block is 1,000 g / mol to 500,000 g / mol. In a specific embodiment, 2,000 g / mol to 300,000 g / mol. In another embodiment, it is from 2,500 g / mol to 100,000 g / mol.

In one embodiment of the present specification, the number average molecular weight of the hydrophobic block is 1,000 g / mol to 500,000 g / mol. In a specific embodiment, 2,000 g / mol to 300,000 g / mol. In another embodiment, it is from 2,500 g / mol to 100,000 g / mol.

According to the exemplary embodiment of the present specification, in the case of the block polymer, the partition and division of the hydrophilic block and the hydrophobic block are clear, so that phase separation is easy, and ion transfer may be easy. According to one embodiment of the present specification, in the case of including a unit derived from the halogenated compound represented by Chemical Formula 1, the hydrophilic block and the hydrophobic block are more clearly distinguished, and thus the ion transfer effect may be superior to that of the conventional polymer. have.

The block polymer refers to a polymer in which one block and one or more blocks different from the block are connected to each other by a main chain of the polymer.

By “hydrophilic block” herein is meant a block having an ion exchange group as a functional group. Here, the functional group is -SO ₃ H, -SO ₃ ^- M ⁺ , -COOH, -COO ^- M ⁺ , -PO ₃ H ₂ , -PO ₃ H ^- M ⁺ , -PO ₃ ^2- 2M ⁺ , —O (CF ₂ ) _m SO ₃ H, —O (CF ₂ ) _m SO ₃ ^- M ⁺ , —O (CF ₂ ) _m COOH, —O (CF ₂ ) _m COO ^- M ⁺ , —O (CF ₂ may be at least one selected from the group consisting of ^{_{2M + -) m PO 3 H}} 2, -O (CF 2) m PO 3 H - M + , and _{-O (CF 2) m PO 3} 2. Here, M may be a metallic element. That is, the functional group may be hydrophilic.

As used herein, the term "block having an ion exchange group" means a block containing an average of 0.5 or more represented by the number of ion exchange groups per structural monomer constituting the block, and an average of 1.0 or more ions per structural monomer. It is more preferable to have an exchanger.

By “hydrophobic block” herein is meant the polymer block which is substantially free of ion exchange groups.

The term "block having substantially no ion exchange group" in the present specification means a block having an average of less than 0.1 represented by the number of ion exchange groups per structural monomer constituting the block, and more preferably 0.05 or less on average. It is more preferable if it is a block which does not have an ion exchange group at all.

In one embodiment of the present specification, the polymer further includes a brancher.

Branchers herein serve to link or crosslink the polymer chains.

In the present specification, in the case of the polymer further including the brancher, the brancher may directly constitute the main chain of the polymer, and may improve the mechanical density of the thin film. For example, the branched polymers of the present invention can be post-treated sulfonated by polymerizing branched hydrophobic blocks that do not contain acid substituents and branched hydrophilic blocks that include acid substituents. Without the post-sulfonation or cross-linking of the sulfonated polymer, the brancher directly forms the main chain of the polymer and maintains the mechanical density of the thin film. Minority blocks and hydrophilic blocks that impart ionic conductivity to the thin film may alternately lead to chemical bonding.

In one embodiment of the present specification, the polymer further includes a brancher derived from a compound of Formula 3 or a brancher represented by Formula 4 below.

[Formula 3]

[Formula 4]

In Chemical Formulas 3 and 4,

X is S; O; CO; SO; SO ₂ ; NR; Hydrocarbon-based or fluorine-based conjugates,

R is an aromatic ring substituted with a halogen group; Or an aliphatic ring substituted with a halogen group,

l is an integer from 0 to 100,

when l is 2 or more, two or more X are the same as or different from each other,

Y1 and Y2 are the same as or different from each other, and each independently an aromatic ring substituted with one or two or more substituents selected from the group consisting of a hydroxy group and a halogen group; Or an aliphatic ring substituted with one or two or more substituents selected from the group consisting of a hydroxy group and a halogen group,

Z is a trivalent organic group.

In the present specification, a brancher derived from the compound of Formula 3 may include an aromatic ring substituted with a halogen group of each of Y1 and Y2; Or a halogen group in the aliphatic ring substituted with a halogen group may act as a branch while being separated from the aromatic ring or aliphatic ring.

In one embodiment of the present specification, l is 3 or more.

In one embodiment of the present specification, X is S.

In another exemplary embodiment, X is a haloalkyl group.

In another embodiment of the present specification, X is NR.

In one embodiment of the present specification, Y1 and Y2 are the same as or different from each other, and are each independently a halogen substituted aromatic ring.

In one embodiment of the present specification, Y1 and Y2 are the same as or different from each other, and are each independently a fluorine-substituted aromatic hydrocarbon ring.

In another exemplary embodiment, Y1 and Y2 are each a fluorine substituted phenyl group. Specifically, 2,4-phenyl, 2,6-phenyl, 2,3-phenyl, 3,4-phenyl and the like are not limited thereto.

In one embodiment of the present specification, the compound represented by Formula 3 may be represented by any one of the following structures.

In the above structure, X, 1 and R are the same as defined in the formula (3).

According to an exemplary embodiment of the present specification, Z in Chemical Formula 4 may be represented by any one of the following Chemical Formulas 4-1 to 4-4.

[Formula 4-1]

[Formula 4-2]

[Formula 4-3]

[Formula 4-4]

In Chemical Formulas 4-1 to 4-4,

L2 To L8 are the same as or different from each other, and each independently a direct bond; -S-; -O-; -CO-; Or -SO _2- ,

R10 to R20 are the same as or different from each other, and each independently hydrogen; heavy hydrogen; Halogen group; Cyano group; Nitrile group; Nitro group; Hydroxyl group; Substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; Substituted or unsubstituted alkoxy group; Substituted or unsubstituted alkenyl group; Substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,

m, n, o, r, t, u and v are each an integer from 1 to 4,

p, q, and s are each an integer of 1 to 3,

w is an integer from 1 to 6,

When m, n, o, p, q, r, s, t, u, v and w are each an integer of 2 or more, the structures in the two or more parentheses are the same or different from each other.

In one embodiment of the present specification, L1 is CO.

In another exemplary embodiment, L1 is SO ₂ .

In another exemplary embodiment, L1 is S.

In another embodiment, L2 is CO.

In another exemplary embodiment, L2 is SO ₂ .

In another embodiment, L2 is S.

In one embodiment of the present specification, L3 is CO.

In another exemplary embodiment, L3 is SO ₂ .

In another embodiment, L3 is S.

In one embodiment of the present specification, L4 is CO.

In another exemplary embodiment, L4 is SO ₂ .

In one embodiment of the present specification, L5 is a direct bond.

In another embodiment, L6 is a direct bond.

In one embodiment of the present specification, L7 is a direct bond.

In one embodiment of the present specification, R10 to R20 are hydrogen.

In one embodiment of the present specification, R16 is a halogen group.

In another exemplary embodiment, R16 is fluorine.

In addition, in an exemplary embodiment of the present specification, the brancher represented by Chemical Formula 4 may be represented by any one of the following structures.

Examples of the substituents herein are described below, but are not limited thereto.

As used herein, the term "substituted" means that a hydrogen atom bonded to a carbon atom of the compound is replaced with another substituent, and the position to be substituted is not limited to a position where the hydrogen atom is substituted, that is, a position where a substituent may be substituted, and two or more. When substituted, two or more substituents may be the same or different from one another.

In the present specification, the hydrocarbon-based means an organic compound consisting of only carbon and hydrogen, and includes a straight chain, branched chain, cyclic hydrocarbon, and the like, but is not limited thereto. In addition, it may include a single bond, a double bond or a triple bond, but is not limited thereto.

In the present specification, the fluorine-based conjugate means that some or all of the carbon-hydrogen bonds in the hydrocarbon system are substituted with fluorine.

In the present specification, the aromatic ring may be an aromatic hydrocarbon ring or an aromatic hetero ring, and may be monocyclic or polycyclic.

Specifically, as the aromatic hydrocarbon ring, monocyclic aromatic and naphthyl groups, binaphthyl groups, anthracenyl groups, phenanthrenyl groups, pyrenyl groups, peryllenyl groups, tetrasenyl groups, chrysenyl groups such as phenyl groups, biphenyl groups and terphenyl groups And polycyclic aromatics such as fluorenyl group, acenaphthasenyl group, triphenylene group, and fluoranthene group, and the like.

In the present specification, the aromatic heterocycle means a structure including one or more hetero atoms such as O, S, N, Se, or the like instead of a carbon atom in the aromatic hydrocarbon ring. Specifically, thiophene group, furan group, pyrrole group, imidazole group, thiazole group, oxazole group, oxadiazole group, triazole group, pyridyl group, bipyridyl group, pyrimidyl group, triazine group, triazole group, acridil group, Pyridazine group, pyrazinyl group, quinolinyl group, quinazoline group, quinoxalinyl group, phthalazinyl group, pyrido pyrimidinyl group, pyrido pyrazinyl group, pyrazino pyrazinyl group, isoquinoline group, indole group, Carbazole group, benzoxazole group, benzoimidazole group, benzothiazole group, benzocarbazole group, benzothiophene group, dibenzothiophene group, benzofuranyl group, phenanthroline group, thiazolyl group, isoxazolyl group , Oxdiazolyl group, thiadiazolyl group, benzothiazolyl group, phenothiazinyl group, dibenzofuranyl group, and the like, but are not limited thereto.

In the present specification, the aliphatic ring may be an aliphatic hydrocarbon ring or an aliphatic hetero ring, and may be monocyclic or polycyclic. Examples of the aliphatic ring include a cyclopentyl group, a cyclohexyl group, and the like, but are not limited thereto.

In this specification, an organic group, an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group, an aralkyl group, etc. are mentioned. This organic group may contain the bond and substituents other than hydrocarbon groups, such as a hetero atom, in the said organic group. The organic group may be any of linear, branched and cyclic.

In the present specification, the trivalent organic group means a trivalent group having three bonding positions in an organic compound.

In addition, the organic group may form a cyclic structure, may form a cyclic structure, and may form a bond including a hetero atom so long as the effect of the invention is not impaired.

Specifically, the bond containing hetero atoms, such as an oxygen atom, a nitrogen atom, and a silicon atom, is mentioned. Specific examples include ether bonds, thioether bonds, carbonyl bonds, thiocarbonyl bonds, ester bonds, amide bonds, urethane bonds, imino bonds (-N = C (-A)-,-C (= NA) -A represents a hydrogen atom or an organic group), and a carbonate bond, a sulfonyl bond, a sulfinyl bond, an azo bond, etc. are mentioned, It does not limit this.

The cyclic structure may include the aforementioned aromatic ring, aliphatic ring, and the like, and may be monocyclic or polycyclic.

In the present specification, the alkyl group may be linear or branched chain, carbon number is not particularly limited, but is preferably 1 to 50. Specific examples include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, t-butyl, pentyl, hexyl and heptyl groups.

In the present specification, the alkenyl group may be linear or branched chain, the carbon number is not particularly limited, but is preferably 2 to 40. Specific examples include vinyl, 1-propenyl, isopropenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 3-methyl-1- Butenyl, 1,3-butadienyl, allyl, 1-phenylvinyl-1-yl, 2-phenylvinyl-1-yl, 2,2-diphenylvinyl-1-yl, 2-phenyl-2- ( Naphthyl-1-yl) vinyl-1-yl, 2,2-bis (diphenyl-1-yl) vinyl-1-yl, stilbenyl group, styrenyl group and the like, but are not limited thereto.

In the present specification, the cycloalkyl group is not particularly limited, but preferably has 3 to 60 carbon atoms, and especially cyclopentyl group, cyclohexyl group, and the like, but is not limited thereto.

In addition, the present disclosure provides a polymer electrolyte membrane including the polymer described above.

In the case of including a polymer including a monomer derived from the compound according to an exemplary embodiment of the present specification, it has high mechanical strength and high ionic conductivity, and may facilitate phase separation of the electrolyte membrane.

In the present specification, "electrolyte membrane" is a membrane capable of exchanging ions, such as membrane, ion exchange membrane, ion transfer membrane, ion conductive membrane, separator, ion exchange membrane, ion transfer membrane, ion conductive separator, ion exchange electrolyte membrane, ion And a transfer electrolyte membrane or an ion conductive electrolyte membrane.

The polymer electrolyte membrane according to one embodiment of the present specification may be manufactured using materials and / or methods known in the art, except for including a polymer including a monomer derived from the halogenated compound.

According to an exemplary embodiment of the present specification, the ion conductivity of the polymer electrolyte membrane is 0.01 S / cm or more and 0.5 S / cm or less. In another exemplary embodiment, the ion conductivity of the polymer electrolyte membrane is 0.01 S / cm or more and 0.3 S / cm or less.

In one embodiment of the present specification, the ionic conductivity of the polymer electrolyte membrane may be measured under humidification conditions. In this specification, the humidification condition may mean 10% to 100% relative humidity (RH).

In addition, in an exemplary embodiment of the present specification, the ion exchange capacity (IEC) value of the polymer electrolyte membrane is 0.01 mmol / g to 5.0 mmol / g. When the ion exchange capacity is in the range, an ion channel in the polymer electrolyte membrane is formed, and the polymer may exhibit ion conductivity.

In one embodiment of the present specification, the thickness of the polymer electrolyte membrane is 1 μm to 500 μm. The polymer electrolyte membrane having the above range thickness lowers an electrical short and a cross over of an electrolyte material, and may exhibit excellent cation conductivity characteristics.

The present specification also relates to an anode; Cathode; And it provides a membrane-electrode assembly comprising the above-described polymer electrolyte membrane provided between the anode and the cathode.

Membrane-electrode assembly (MEA) is an electrode (cathode and anode) in which the electrochemical catalysis of fuel and air occurs and a polymer membrane in which hydrogen ions are transferred. The electrode (cathode and anode) and the electrolyte membrane are bonded together. It is a single unitary unit.

The membrane-electrode assembly of the present specification is a form in which the catalyst layer of the anode and the catalyst layer of the cathode are in contact with the electrolyte membrane, and may be prepared according to conventional methods known in the art. In one example, the cathode; Anode; And it may be prepared by thermal compression at 100 to 400 ℃ in the state in which the electrolyte membrane located between the cathode and the anode in close contact.

The anode electrode may include an anode catalyst layer and an anode gas diffusion layer. The anode gas diffusion layer may again include an anode microporous layer and an anode electrode substrate.

The cathode electrode may include a cathode catalyst layer and a cathode gas diffusion layer. The cathode gas diffusion layer may further include a cathode microporous layer and a cathode electrode substrate.

FIG. 1 schematically illustrates the principle of electricity generation of a fuel cell. In the fuel cell, the most basic unit for generating electricity is a membrane electrode assembly (MEA), which is an electrolyte membrane 100 and the electrolyte membrane 100. It consists of an anode (200a) and a cathode (200b) electrode formed on both sides of the. Referring to FIG. 1, which illustrates a principle of electricity generation of a fuel cell, an anode 200a generates an oxidation reaction of a fuel such as hydrogen or a hydrocarbon such as methanol and butane to generate hydrogen ions (H +) and electrons (e−). Hydrogen ions move to the cathode 200b through the electrolyte membrane 100. In the cathode 200b, water is generated by reacting hydrogen ions transferred through the electrolyte membrane 100 with an oxidant such as oxygen and electrons. This reaction causes the movement of electrons in the external circuit.

The catalyst layer of the anode electrode is where the oxidation reaction of the fuel occurs, the catalyst is selected from the group consisting of platinum, ruthenium, osmium, platinum-ruthenium alloy, platinum-osmium alloy, platinum-palladium alloy and platinum-transition metal alloy. Can be used. The catalyst layer of the cathode electrode is where the reduction reaction of the oxidant occurs, platinum or platinum-transition metal alloy may be preferably used as a catalyst. The catalysts can be used on their own as well as supported on a carbon-based carrier.

The introduction of the catalyst layer may be carried out by conventional methods known in the art, for example, the catalyst ink may be directly coated on the electrolyte membrane or coated on the gas diffusion layer to form the catalyst layer. At this time, the coating method of the catalyst ink is not particularly limited, but spray coating, tape casting, screen printing, blade coating, die coating or spin coating may be used. Catalytic inks can typically consist of a catalyst, a polymer ionomer, and a solvent.

The gas diffusion layer serves as a passage for the reaction gas and water together with a role as a current conductor, and has a porous structure. Therefore, the gas diffusion layer may include a conductive substrate. As the conductive substrate, carbon paper, carbon cloth, or carbon felt may be preferably used. The gas diffusion layer may further include a microporous layer between the catalyst layer and the conductive substrate. The microporous layer may be used to improve the performance of the fuel cell in low-humidity conditions, and serves to reduce the amount of water flowing out of the gas diffusion layer so that the electrolyte membrane is in a sufficient wet state.

One embodiment of the present specification includes two or more membrane-electrode assemblies; A stack comprising a bipolar plate provided between the membrane-electrode assemblies; A fuel supply unit supplying fuel to the stack; And it provides a polymer electrolyte fuel cell comprising an oxidant supply unit for supplying an oxidant to the stack.

A fuel cell is an energy conversion device that converts chemical energy of a fuel directly into electrical energy. In other words, a fuel cell is a power generation method that uses fuel gas and an oxidant and generates electric power by using electrons generated during the redox reaction.

The fuel cell can be manufactured according to conventional methods known in the art using the membrane-electrode assembly (MEA) described above. For example, it may be prepared by configuring a membrane electrode assembly (MEA) and a bipolar plate (bipolar plate) prepared above.

The fuel cell of the present specification includes a stack, a fuel supply unit and an oxidant supply unit.

3 schematically illustrates the structure of a fuel cell, in which the fuel cell includes a stack 60, an oxidant supply unit 70, and a fuel supply unit 80.

The stack 60 includes one or two or more membrane electrode assemblies as described above, and includes two or more separators interposed therebetween when two or more membrane electrode assemblies are included. The separator serves to prevent the membrane electrode assemblies from being electrically connected and to transfer fuel and oxidant supplied from the outside to the membrane electrode assembly.

The oxidant supply unit 70 serves to supply the oxidant to the stack 60. Oxygen is typically used as the oxidizing agent, and may be used by injecting oxygen or air into the pump 70.

The fuel supply unit 80 serves to supply fuel to the stack 60, and to the fuel tank 81 storing fuel and the pump 82 supplying fuel stored in the fuel tank 81 to the stack 60. Can be configured. As fuel, hydrogen or hydrocarbon fuel in gas or liquid state may be used. Examples of hydrocarbon fuels include methanol, ethanol, propanol, butanol or natural gas.

The fuel cell may be a polymer electrolyte fuel cell, a direct liquid fuel cell, a direct methanol fuel cell, a direct formic acid fuel cell, a direct ethanol fuel cell, or a direct dimethyl ether fuel cell.

When the electrolyte membrane according to one embodiment of the present specification is used as an ion exchange membrane of a fuel cell, the above-described effects can be obtained.

In addition, an exemplary embodiment of the present specification includes a positive electrode cell including a positive electrode and a positive electrode electrolyte; A cathode cell comprising a cathode and a cathode electrolyte; And it provides a redox flow battery comprising a polymer electrolyte membrane according to one embodiment of the present specification provided between the cathode cell and the anode cell.

The redox flow battery (redox flow battery) is an electrochemical storage device that stores the chemical energy of an active material directly as electrical energy. It is a system in which the active material contained in the electrolyte is oxidized, reduced, and charged and discharged. to be. The redox flow battery uses a principle that charges and discharges are exchanged when electrons containing active materials having different oxidation states meet with an ion exchange membrane interposed therebetween. In general, a redox flow battery is composed of a tank containing an electrolyte solution, a battery cell in which charging and discharging occurs, and a circulation pump for circulating the electrolyte solution between the tank and the battery cell, and the unit cell of the battery cell includes an electrode, an electrolyte, and an ion. Exchange membrane.

When the electrolyte membrane according to one embodiment of the present specification is used as an ion exchange membrane of a redox flow battery, the above-described effects may be exhibited.

The redox flow battery of the present specification may be manufactured according to conventional methods known in the art, except for including the polymer electrolyte membrane according to one embodiment of the present specification.

As shown in FIG. 2, the redox flow battery is divided into the positive electrode cell 32 and the negative electrode cell 33 by the electrolyte membrane 31. The anode cell 32 and the cathode cell 33 include an anode and a cathode, respectively. The anode cell 32 is connected to the anode tank 10 for supplying and discharging the anode electrolyte 41 through a pipe. The cathode cell 33 is also connected to the cathode tank 20 for supplying and discharging the cathode electrolyte 42 through a pipe. The electrolyte is circulated through the pumps 11 and 21, and an oxidation / reduction reaction (that is, a redox reaction) in which the oxidation number of ions changes occurs, thereby causing charge and discharge at the anode and the cathode.

Hereinafter, the present invention will be described in detail with reference to Examples. However, embodiments according to the present disclosure may be modified in various other forms, and the scope of the present disclosure is not interpreted to be limited to the embodiments described below. The embodiments of the present specification are provided to more fully describe the present specification to those skilled in the art.

<Manufacture example 1>

In a 250 mL round flask equipped with a condenser, 5.0000 g (0.012135 mol, 1eq) of 3,3'-dibromo-4,4'-difluorodiphenyl sulfone, 13.9689 g of perfluorinated 4-bromobenzene ( 0.026696 mol, 2.2 eq) and 15.4233 g (0.242695 mol, 20 eq) of zero-valent copper were added, and 30 mL of dimethyl acetamide (DMAc) was added thereto. After the temperature of the reaction system was raised to 160 ° C., the reaction was performed for 48 hours. The reaction mixture was cooled to room temperature and excess ethanol was poured into the reactor. After filtering the copper using a Celite Fiter (Celite Fiter), it was washed several times with a large amount of ethanol. After evaporation of the collected solution after filtration, the remaining DMAc was precipitated by the salting-out method. After filtering, the filtered solid was recrystallized with ethanol / water and dried in an oven to obtain a final compound.

<Manufacture example 2>

8.4015 g (0.012135 mol, 1eq), perfluorinated 4,4'-sulfonylbis (2-bromo-1-((40fluorophenyl) sulfonyl) benzene) in 250 mL round flask equipped with condenser 13.9689 g (0.026696 mol, 2.2 eq) of 4-bromobenzene and 15.4233 g (0.242695 mol, 20 eq) of zero-valent copper were added thereto, and 40 mL of dimethyl acetamide (DMAc) was added thereto. After the temperature of the reaction system was raised to 160 ° C., the reaction was performed for 48 hours. The reaction mixture was cooled to room temperature and excess ethanol was poured into the reactor. After filtering the copper using a Celite Fiter (Celite Fiter), it was washed several times with a large amount of ethanol. After evaporation of the collected solution after filtration, the remaining DMAc was precipitated by the salting-out method. After filtering, the filtered solid was recrystallized with ethanol / water and dried in an oven to obtain a final compound.

Example 1 Polymer Synthesis

[Formula 1-1-1]

3.0000 g [2.6341 mmol] of the compound represented by Formula 1-1-1, 4,4, '-thiobisbenzenethiol 0.6595 in a 250 mL round flask equipped with a dean-stark device and a condenser g [2.6341 mmol] was added thereto, and the reaction was initiated using 1.4561 g [10.536 mmol] of potassium carbonate in a nitrogen atmosphere using 18 ml of NMP (N-methyl-2-pyrrolidone) and 9 ml of toluene.

The reaction mixture was then stirred for 4 hours in an oil bath at 140 ° C. again, adsorbing and removing the azeotrope on the molecular sieves of the Dean-Stark apparatus while toluene was refluxed, followed by reaction temperature. The temperature was raised to 175 ℃ and polycondensation reaction for 6 hours.

Then, the temperature of the reactant was reduced to room temperature, the reactant was poured into excess methanol to separate the copolymer from the solvent, and the obtained copolymer was added to water again to remove potassium carbonate, and then the resulting copolymer was filtered. A polymer material was prepared by drying at least 12 hours in a vacuum oven at ℃.

1 g of the copolymer prepared above was dissolved in 5 mL of NMP to make a 20 wt / v% NMP solution, coated and dried on a glass substrate, and a film having a thickness of about 20 μm was produced. The ion conductivity of the electrolyte membrane was 0.132 S. / cm.

Example 2 Multiblock Polymer Synthesis

3.0000 g [2.6341 mmol] of the compound represented by Formula 1-1-1, 4,4, '-thiobisbenzenethiol 0.6595 in a 250 mL round flask equipped with a dean-stark device and a condenser g [2.6341 mmol] was added thereto, and the reaction was initiated using 1.4561 g [10.536 mmol] of potassium carbonate in a nitrogen atmosphere using 18 ml of NMP (N-methyl-2-pyrrolidone) and 9 ml of toluene.

The reaction mixture was then stirred for 4 hours in an oil bath at 140 ° C. again, adsorbing and removing the azeotrope on the molecular sieves of the Dean-Stark apparatus while toluene was refluxed, followed by reaction temperature. The temperature was raised to 175 ℃ and polycondensation reaction for 6 hours.

After the reaction was completed, the temperature of the reactant was reduced to room temperature, and then 0.6697 g [2.6341 mmol] of 4,4'-difluorodiphenyl sulfone and 0.6595 g [2.6341] of 4,4, '-thiobisbenzenethiol were placed in the same flask. mmol] and 6.6 ml of NMP (N-methyl-2-pyrrolidone) and 3.3 ml of toluene were used to start the reaction again using 1.4561 g [10.536 mmol] of potassium carbonate as a catalyst in a nitrogen atmosphere.

The reaction mixture was then stirred for 4 hours in an oil bath at 140 ° C. again, adsorbing and removing the azeotrope on the molecular sieves of the Dean-Stark apparatus while toluene was refluxed, followed by reaction temperature. The temperature was raised to 175 ℃ and polycondensation reaction for 6 hours.

Then, the temperature of the reactant was reduced to room temperature, the reactant was poured into excess methanol to separate the copolymer from the solvent, and the obtained copolymer was added to water again to remove potassium carbonate, and then the resulting copolymer was filtered. Drying in a vacuum oven at 12 ℃ for more than 12 hours to prepare a multi-block copolymer in which the hydrophobic block and the hydrophilic block alternately by chemical bonding.

1 g of the copolymer prepared above was dissolved in 5 mL of NMP to form a 20 wt / v% NMP solution, coated and dried on a glass substrate, and a film having a thickness of about 20 μm was produced. The ion conductivity of the electrolyte membrane was 0.12 S. / cm.

Comparative Example 1

3.0000 g [6.5455 mmol] of disodium 2,2'-disulfonate-4,4'-difluorodiphenyl sulfone in 250 mL round flask equipped with dean-stark device and condenser Add 1.6642 g [6.5455 mmol] of 4'-difluorodiphenyl sulfone and 3.2779 g [13.091 mmol] of 4,4, '-thiobisbenzenethiol, 40 ml of NMP (N-methyl-2-pyrrolidone) The reaction was initiated using 7.2367 g [52.364 mmol] of potassium carbonate in a nitrogen atmosphere using 20 ml of toluene.

The reaction mixture was then stirred for 4 hours in an oil bath at 140 ° C. again, adsorbed to the molecular sieves of the Dean-Stark apparatus while the toluene was refluxed to remove the azeotrope, and then the reaction temperature. The temperature was raised to 175 ℃ and polycondensation reaction for 6 hours.

Then, the temperature of the reactant was reduced to room temperature, the reactant was poured into excess methanol to separate the copolymer from the solvent, and the obtained copolymer was added to water again to remove potassium carbonate, and then the resulting copolymer was filtered. It was dried in a vacuum oven at 12 ℃ or more to prepare a random copolymer.

The copolymer prepared above was dissolved in 5 mL of NMP to make a 20 wt / v% NMP solution, coated and dried on a glass substrate, and a film having a thickness of about 20 μm was produced, and the ion conductivity of the electrolyte membrane was 0.1 S. / cm.

As shown in the electrolyte membrane performance evaluation of Examples 1, 2 and Comparative Example, it can be seen that the ion conductivity of the electrolyte membrane prepared in Examples 1 and 2 is higher than the ion conductivity of the electrolyte membrane prepared in Comparative Example.

Therefore, the electrolyte membrane including the copolymer according to the exemplary embodiment of the present application may exhibit an excellent ion conductivity than the conventional electrolyte membrane.

100: electrolyte membrane
200a: anode
200b: cathode
10, 20: tank
11, 21: pump
31: electrolyte membrane
32: anode cell
33: cathode cell
41: anode electrolyte
42: cathodic electrolyte
60: stack
70: oxidant supply
80: fuel supply
81: fuel tank
82: pump

Claims (12)

Compound represented by the following formula (1):
[Formula 1]

In Chemical Formula 1,
A1 and A2 are the same as or different from each other, and each independently selected from the group consisting of F, Cl, and Br,
B1 to B3 are SO ₂ ,
C1 and C2 are the same as or different from each other, and are each independently represented by the following formula (2),
[Formula 2]

In Formula 2, M is hydrogen or an alkali metal ion,
g is 1, h is 1, i and j are each an integer from 2 to 6,
R ₁ to R ₄ are hydrogen,
a and b are each an integer of 0 or 1, c and f are 4, and d and e are 3. The compound of claim 1, wherein the compound of Formula 1 is represented by the following Formula 1-1 or 1-2:
[Formula 1-1]

[Formula 1-2]

The definitions of A1, A2, B1 to B3, C1 C2, R1 to R4, and c to f of Chemical Formulas 1-1 and 1-2 are the same as those of Chemical Formula 1. The method according to claim 1, Formula 2 is

And M is hydrogen or an alkali metal. delete delete The compound of claim 1, wherein the compound represented by Chemical Formula 1 is any one of the following Chemical Formulas:

A polymer comprising units derived from a compound according to any one of claims 1 to 3 and 6. The polymer of claim 7 wherein the polymer comprises 50 to 60 mole% of units derived from the compound. A polymer electrolyte membrane comprising the polymer of claim 7. Anode; Cathode; And a polymer electrolyte membrane of claim 9 provided between the anode and the cathode. At least two membrane-electrode assemblies according to claim 10;
A stack comprising a bipolar plate provided between the membrane-electrode assemblies;
A fuel supply unit supplying fuel to the stack; And
A polymer electrolyte fuel cell comprising an oxidant supply unit for supplying an oxidant to the stack. A cathode cell comprising an anode and an anode electrolyte solution;
A cathode cell comprising a cathode and a cathode electrolyte; And
Redox flow battery comprising the polymer electrolyte membrane of claim 9 provided between the positive electrode and the negative electrode cell.

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