KR20080099967A - Sulfonated triphenylamine derivative and polimer prepared from the same - Google Patents

Abstract

An electrolyte film manufactured from a sulfonated triphenylamine derivative is provided to ensure high hydrogen ion conductivity and excellent mechanical properties, to control the distribution, location and number of a sulfonic acid group in a polymer backbone, and to manufacture a thin film effectively by having no degradation of the properties of membrane according to the increase of a sulfonic acid group. A sulfonated triphenylamine derivative is represented by the chemical formula 1. In the chemical formula 1, X1 and X2 are independently selected from -NO2, -F, -Cl, -Br and -I; and M1 is selected from -H, -Na and -K. The polymer prepared by the same is a sulfonated poly(arylene ether amine) including a repeating unit of the chemical formula 2. In the chemical formula 2, M1 is selected from -H, -Na and -K, R1 is selected from an arylene, alkylene and their mixed functional group.

Description

Sulfonated triphenylamine derivatives and polymers prepared therefrom {SULFONATED TRIPHENYLAMINE DERIVATIVE AND POLIMER PREPARED FROM THE SAME}

1 is a graph showing ¹ H NMR spectra of sulfonated poly (arylene ether amine) copolymers prepared according to Example 3 of the present invention.

2 is a graph showing ¹ H NMR spectra of sulfonated poly (arylene ether amine) copolymers prepared according to Example 4 of the present invention.

3 is a graph showing the ¹ H NMR spectrum of the sulfonated poly (arylene ether amine) copolymer prepared according to Example 5 of the present invention.

4 is a graph showing the hydrogen ion conductivity of the sulfonated poly (arylene ether amine) electrolyte membrane prepared in Examples 6 to 10 and Nafion 115.

The present invention relates to sulfonated triphenylamine derivatives and polymers prepared using the same. The present invention also relates to a fuel cell using an electrolyte membrane including the polymer and a membrane electrode assembly including the electrolyte membrane.

Fuel cell is an energy conversion device that produces electricity directly by electrochemical reaction of hydrogen and oxygen. It is not only able to obtain energy with high efficiency but also very advantageous in terms of environment conservation. Batteries generally require anodes and cathodes, and electrolytes that move electrons (or protons) between them. Fuel cells are no exception, and in general, a carbon electrode containing a platinum catalyst is used as an electrode for oxidation and reduction, and an ionic solid is used as an electrolyte. Unlike secondary batteries that are charged by electrochemical reactions inside batteries, fuel cells can be used semi-permanently by continuously injecting fuel such as hydrogen or methanol.

Fuel cells have been developed in various ways depending on the driving temperature, capacity, and purpose of use.However, they can be charged in a lightweight and simple manner with Polymer Electrolyte Membrane Fuel Cell (PEMFC) using a proton exchange membrane. Research is focused on the Direct Methanol Fuel Cell (DMFC), which uses methanol as a fuel, which is expected to replace car batteries. The proton exchange membrane used today is a fluorinated ionomer named Nafion produced by Du Pont in the United States, and it is known that Gore's Primea material has the advantage of forming a thinner membrane. In order to improve the performance of the entire fuel cell, it is very important to improve the properties of the exchange membrane.In the basic skeleton of the conventional Teflon-based fluorinated ionomer, if the mechanical strength is increased, various properties including proton conductivity are inevitably increased under high driving temperature. There is a tendency to deteriorate, and research into a new type of proton exchange membrane having excellent chemical stability and mechanical properties simultaneously is being actively conducted.

Poly (arylene amine) -based polymers have been actively studied for their application to fuel cells because of their excellent heat resistance, mechanical strength, and processability in addition to the general characteristics of polymers represented by light weight, insulation, and chemical resistance. For example, the journal Gao Y .; et al., Journal of Membrane Science 2003, 227, 39. discloses poly (phthalazinone arylene ether) {poly ( It has been reported how various sulfonated poly (phthalazinone arylene ethers) are prepared using a post-sulfonation process of phthalazinone arylene ether). However, the post-treatment sulfonation method is generally difficult to control the distribution, position, and number of sulfonic acid groups (-SO ₃ H) of the polymer skeleton, and is a gelation phenomenon which is a kind of side reaction during the post-treatment sulfonation process. There was a problem in the process of the electrolyte membrane.

In order to overcome this problem, a study on the preparation of various sulfonated (phthalazinone arylene ether) copolymers by a direct copolymerization method using a difluoro monomer containing a sulfonic acid group has been reported (Gao Y. et al., Journal of Polymer Science: Part A: Polymer Chemistry 2003, 41, 2731.). The sulfonated polymer has better thermal stability and higher proton conductivity than Nafion. However, in the test of the membrane electrode assembly (MEA) of the fuel cell, the sulfonated polymer compared with the electrolyte membrane partially made of the fluorinated polymer is generally used with the perfluorinated polymer-based bind. There is a problem of poor affinity.

In order to solve the problems of the prior art as described above, the present invention can be applied to the proton (H ⁺ ) exchange membrane for fuel cells that can be used at low and high temperatures (100 ~ 200 ℃), has excellent proton conductivity and excellent mechanical properties In addition to being chemically stable, it has a chemical structure with a low degree of swelling of the electrolyte membrane due to the trifluoromethyl substituent in the polymer chain, and has a good relationship with the perfluorinated polymer-based bind commonly used for testing membrane electrode assemblies of fuel cells. It is an object to provide partially fluorinated sulfonated poly (arylene ether amine) based polymers that can show chemical conversion.

In addition, the present invention is to provide a monomer for forming the sulfonated poly (arylene ether amine) -based polymer.

In addition, the present invention is to provide an electrolyte membrane comprising the sulfonated poly (arylene ether amine) -based polymer and can be used as a proton exchange membrane for fuel cells.

The present invention provides a sulfonated triphenylamine derivative represented by the following formula (1).

[Formula 1]

In Formula 1, X ¹ and X ² are each independently selected from -NO ₂ , -F, -Cl, -Br and -I;

M ¹ is selected from -H, -Na, and -K.

In addition, the present invention provides a polymer prepared by using the sulfonated triphenylamine derivative represented by Chemical Formula 1.

The present invention also provides a fuel cell using an electrolyte membrane including the polymer and a membrane electrode assembly including the electrolyte membrane.

Hereinafter, the present invention will be described in detail.

<Sulfonated Triphenylamine Derivatives>

The sulfonated triphenylamine derivative represented by Chemical Formula 1 according to the present invention is a compound having one sulfonated phenyl group and two 3-trifluoromethylphenyl groups substituted with halogen or nitro groups. In this case, the parameters X ¹ and X ² in the compound represented by Formula 1 may be the same or different from each other.

In addition, the aromatic ring of the sulfonated triphenylamine derivative represented by Chemical Formula 1 may further include one or more substituents such as a C ₁ to C ₃₀ alkyl group, a C ₆ to C ₃₀ aryl group, and such a compound. It is included in the scope of the present invention.

The sulfonated triphenylamine derivative represented by Chemical Formula 1 may be prepared according to a route of the following Scheme 1, without limitation. However, Scheme 1 below is merely illustrative, and the method for preparing sulfonated triphenylamine derivative according to the present invention is not limited by the following scheme.

Scheme 1

In Scheme 1, a sulfonated triphenylamine derivative may be prepared by reacting 1 equivalent of aniline and 2 equivalents of fluoromethylbenzene derivative. In this case, unlike Scheme 1, triphenylamine derivatives which are not sulfonated may be prepared by using two kinds of fluoromethylbenzene derivatives having different substituents of X ¹ as reactants, respectively. Thereafter, a sulfonated triphenylamine derivative represented by Chemical Formula 1 may be finally manufactured through a sulfonation step.

In Scheme 1, the Pd catalyst is not particularly limited and may be conventionally known in the art, and may be optionally used with a ligand. Examples of the ligand include, but are not limited to, bis (diphenylphosphino) -1,1'-dynaphthyl (BINAP). In addition, examples of the base include potassium phosphate (K ₃ PO ₄ ), but are not limited thereto, and common bases known in the art may be used.

In addition, in the scheme 1, the sulfonation may include, for example, reacting a triphenylamine derivative with trimethylsilyl chloro sulfonate, and then introducing a metal alkoxide to introduce a sulfonic acid salt, followed by acid treatment to sulfonic acid. Salts can be converted to sulfonic acids, but are not limited thereto.

In addition, the method for producing a sulfonated triphenylamine derivative represented by the formula (1), using a reactant exhibiting the same or similar effects as the reactants used in Scheme 1 or by a scheme similar to the scheme (scheme) Include.

<Polymer>

The present invention provides a polymer prepared using a sulfonated triphenylamine derivative represented by Chemical Formula 1, preferably a sulfonated poly (arylene ether amine) -based polymer.

The polymer of the present invention may be prepared using a sulfonated triphenylamine derivative represented by Chemical Formula 1 as a monomer for nucleophilic aromatic substitution reaction.

When performing a nucleophilic aromatic substitution reaction by a nucleophile using the sulfonated triphenylamine derivative represented by Chemical Formula 1 according to the present invention, the parameters X ¹ and X ² in the compound represented by Chemical Formula 1 are substituted. The substitution reaction may take place at the designated position, and the parameters X ¹ and X ² may be leaving groups.

At this time, when performing a nucleophilic aromatic substitution reaction using a nucleophile having two or more reactive functional groups in the molecule and the compound represented by the formula (1), the polymerization reaction proceeds to produce a sulfonated polymer. In this case, non-limiting examples of the reactive functional group include a hydroxy group, an amine group, a thiol group, a carbanion, and the like, and the nucleophile may be a nucleophile in which these reactive functional groups are combined. By way of non-limiting example, if the nucleophile having two or more reactive functional groups in the molecule is a diol compound such as HO-R-OH, wherein R is alkylene or arylene, sulfonated polymer, preferably sulfonated poly (Arylene ether amines) can be prepared.

Specifically, the polymer according to the present invention may be a sulfonated poly (arylene ether amine) containing a repeating unit represented by the following formula (2).

[Formula 2]

In Formula 2, M ¹ is selected from -H, -Na, and -K;

R ¹ is selected from arylene, alkylene and hybrid functional groups thereof.

In addition, the polymer according to the present invention not only includes a repeating unit represented by Formula 2, but also a repeating unit selected from the group consisting of a repeating unit represented by the following Formula 3 and a repeating unit represented by the following Formula 4. Sulfonated poly (arylene ether amine).

[Formula 3]

In Formula 3, M ¹ is selected from -H, -Na and -K;

R ² is not the same as R ¹ and is selected from arylene, alkylene and hybrid functional groups thereof;

[Formula 4]

In Formula 4, M ² is selected from -H, -Na and -K;

Y is -S (= 0) ₂ -or -C (= 0)-;

R ³ is selected from arylene, alkylene and hybrid functional groups thereof.

Preferably, the polymer according to the present invention is sulfonated poly (arylene ether amine) represented by the following formula (5), sulfonated poly (arylene ether amine) represented by the following formula (6) and sulfonated represented by the formula (7) Sulfonated poly (arylene ether amine) selected from the group consisting of poly (arylene ether amines).

[Formula 5]

In Formula 5, M ¹ is selected from -H, -Na, and -K;

R ¹ is selected from arylene, alkylene and hybrid functional groups thereof;

n is an integer from 5 to 200;

[Formula 6]

In Formula 6, M ¹ is selected from -H, -Na, and -K;

R ¹ and R ² are different from each other and are each independently selected from arylene, alkylene and hybrid functional groups thereof;

n and m are each independently an integer from 5 to 200;

[Formula 7]

In Formula 7, M ¹ and M ² are each independently selected from -H, -Na, and -K;

Y is -S (= 0) ₂ -or -C (= 0)-;

R ¹ and R ³ are each independently selected from arylene, alkylene and hybrid functional groups thereof;

n and m are each independently an integer of 5 to 200.

In Formula 7, R ¹ and R ³ may be the same or different from each other, but the same is preferable.

In addition, in R ¹ to R ³ of Formula 2 to Formula 7, the arylene is C ₆ ~ C ₁₀₀ arylene, the alkylene is a linear, branched, or branched alkyl group of C ₆ ~ C ₁₀₀ Can be.

Representative examples of the sulfonated poly (arylene ether amine) represented by Chemical Formulas 5 to 7 according to the present invention include compounds represented by the following chemical formulas. However, the compounds represented by the following formulas merely illustrate sulfonated poly (arylene ether amine), and the sulfonated poly (arylene ether amine) of the present invention is not limited to those illustrated below.

[Formula 5a]

[Formula 5b]

[Formula 6a]

[Formula 6b]

[Formula 7a]

In Formulas 5a, 5b, 6a, 6b, and 7a, n and m are each independently an integer of 5 to 200.

The sulfonated poly (arylene ether amine) represented by Chemical Formulas 5 to 7 of the present invention is subjected to nucleophilic aromatic substitution reaction using sulfonated triphenylamine derivatives, diol derivatives and comonomers represented by Chemical Formula 1 above. It can be prepared through.

Hereinafter, the sulfonated poly (arylene ether amine) represented by Chemical Formulas 5 to 7 will be described in more detail.

The sulfonated poly (arylene ether amine) homopolymer represented by the general formula (5) of the present invention is prepared by dissolving and reacting the sulfonated triphenylamine derivative, the diol derivative and the base represented by the formula (1) in a polar aprotic solvent. Can be. As a non-limiting example, the reaction can be represented by the following scheme 2.

Scheme 2

In Scheme 2, R ¹ is selected from arylene, alkylene and hybrid functional groups thereof; n is an integer of 5 to 200.

In addition, the sulfonated poly (arylene ether amine) copolymer represented by Chemical Formula 6 of the present invention dissolves the sulfonated triphenylamine derivative represented by Chemical Formula 1, two or more diol derivatives, and a base in a polar aprotic solvent. And react. By way of non-limiting example, the reaction can be represented by the following scheme 3.

Scheme 3

In Scheme 3, R ¹ and R ² are different from each other, each independently selected from arylene, alkylene and hybrid functional groups thereof; n and m are each independently an integer of 5 to 200.

In addition, the sulfonated poly (arylene ether amine) copolymer represented by the general formula (7) of the present invention is a sulfonated triphenylamine derivative, a diol derivative, a sulfonated dichlorine derivative and a base represented by the formula (1) polar aprotic It can be prepared by dissolving in a solvent and reacting. As a non-limiting example, the reaction can be represented by the following scheme 4.

Scheme 4

In Scheme 4, R ¹ is selected from arylene, alkylene and hybrid functional groups thereof; n and m are each independently an integer from 5 to 200; Y is -S (= 0) ₂ -or -C (= 0)-.

In addition, in Schemes 2 to 4, as the sulfonated triphenylamine derivative represented by Chemical Formula 1, the compound represented by Chemical Formula 1a, that is, bis (4-night) containing a sulfone functional group at a para position of triphenylamine Rho-3-trifluoromethylphenyl) phenylamine is used, but is not limited thereto.

[Formula 1a]

The polar aprotic solvent is dimethyl sulfoxide (DMSO), N-methylpyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone (DMI), dimethylacetamide (DMAc), dimethylformamide ( DMF) and tetramethylene sulfone may be used at least one selected from the group consisting of, preferably dimethyl sulfoxide or benzophenone may be used, but is not limited thereto.

The sulfonated triphenylamine derivative and the diol derivative represented by Formula 1 are preferably used at a concentration of 15 to 35 M% with respect to the polar aprotic solvent, respectively, when the concentration is less than 15 M%. There is a problem in obtaining a polymer having a large molecular weight to produce a cyclic compound, and when it exceeds 35 M%, since the ratio of the solvent is reduced compared to the polymer, solubility decreases and a problem in obtaining a polymer having a large molecular weight occurs.

The sulfonated triphenylamine derivative and the diol derivative as described above are dissolved in a polar aprotic solvent and then a base is added to the mixture.

In this case, the base may be potassium carbonate (K ₂ CO ₃ ) and / or cesium carbonate (Cs ₂ CO ₃ ), and the like, and preferably potassium carbonate.

The base may be used in an amount of 0.1 to 5 equivalents based on the sulfonated triphenylamine derivative represented by Chemical Formula 1. If the content of the base is less than 0.1 equivalents, there is a problem in the formation of phenoxide salt of arylene diol, and if the amount exceeds 5 equivalents, there is a problem in stirring the reactants by the excess insoluble catalyst.

The mixture to which the base is added as described above may then be stirred at a temperature of 100 to 140 ° C. for 1 to 2 hours, preferably at 140 ° C. for 1 hour to produce a phenoxide salt. In this case, in order to effectively advance the reaction, a small amount of toluene may be added to effectively remove water generated during the reaction.

Thereafter, the temperature of the reaction may be elevated to a temperature of 160 to 185 ° C., thereby increasing the temperature for 3 to 24 hours, preferably 180 ° C., and stirring for 6 hours to prepare a polymer.

After the reaction is completed, the final sulfonated poly (arylene ether amine) homopolymer may be obtained through purification and drying process. As a non-limiting example of the purification and drying process, after completion of the reaction, the potassium carbonate and the polar aprotic solvent are removed, and the precipitate is dissolved in the polar aprotic solvent once again after drying and precipitated and purified in excess methanol. The precipitate can be vacuum dried in an oven.

The method for preparing a polymer according to the present invention, preferably sulfonated poly (arylene ether amine), uses a reactant that exhibits the same or similar effect as the reactants used in Schemes 2 to 4, or is similar to the above schemes. It also includes a method for manufacturing by route.

The polymer, preferably sulfonated poly (arylene ether amine), according to the present invention introduces a triphenylamine group and a trifluoromethyl substituent into the polymer chain, and shows excellent processability in forming a proton exchange membrane film, and the degree of swelling of the electrolyte membrane. It is small and can improve the affinity with the perfluorinated polymer type | system | group bind generally used in the membrane electrode assembly (MEA) test of a fuel cell.

Accordingly, the present invention provides an electrolyte membrane comprising the polymer of the present invention, preferably sulfonated poly (arylene ether amine). The sulfonated poly (arylene ether amine) has excellent thermoplasticity and solubility, and also has excellent heat resistance of the electrolyte membrane, thereby improving physical properties of the proton exchange membrane for fuel cells. In addition to the polymer of the present invention, the electrolyte membrane according to the present invention may further include conventional polymers and / or inorganic materials known as materials for electrolyte membranes in the art.

The electrolyte membrane of the present invention can be prepared according to conventional methods known in the art using the polymer according to the present invention. Non-limiting examples thereof may be prepared by coating a polymer or a solution thereof according to the invention on a substrate and then separating the electrolyte membrane from the substrate.

In addition, a membrane electrode assembly including the electrolyte membrane and the electrode of the present invention, and a fuel cell including such a membrane electrode assembly are included in the scope of the present invention, and each of them may be prepared according to a conventional method known in the art. Description of these is omitted here. In addition, since the membrane electrode assembly and other specific details for the configuration of the fuel cell including the same in the present invention are known in the art, even if there is no separate description in the present specification can be sufficiently reproduced.

Hereinafter, the present invention will be described in detail with reference to the following Examples. However, the following examples are merely to illustrate the present invention and the present invention is not limited by the following examples.

EXAMPLE

Hereinafter, the structure and physical properties of the monomers and polymers used in the examples were confirmed and measured using the following method.

The structure of the synthesized material was confirmed by infrared spectroscopy (IR) and nuclear magnetic resonance spectroscopy (NMR).

IR plots were obtained from Bruker's EQUINOX-55 FTIR spectrophotometer using films and NMR plots were obtained using Bruker's Fourier Transform AVANCE 400 spectrometer.

-TGA (Thermogravimetric Analysis) was measured using TA Instrument's TA 2200 thermal analyzer system. All were measured under a constant stream of nitrogen.

Example 1 Preparation of Sulfonated Poly (arylene Ether Amine) (Formula 5a)

(Example 1-1: Bis (4-nitro-3-trifluoromethylphenyl) phenylamine preparation)

8.910 g (33 mmol) of 5-bromo-2-nitrobenzotrifluoride, 1.397 g (15 mmol) of aniline, 0.13 g (0.15 g) of tris (dibenzylideneacetone) dipalladium (Pd ₂ (dba) ₃ ) mmol), 0.373 g (0.6 mmol) bis (diphenylphosphino) -1,1'-dynaphthyl (rac-BINAP), 8.915 g (42 mmol) potassium phosphate (K ₃ PO ₄ ), and 1,2 70 mL of dimethoxyethane was stirred at a temperature of 100 ° C. under a nitrogen atmosphere for 36 hours to give the product.

The obtained product was cooled to room temperature, diluted with ethyl acetate, and then the base was removed several times using distilled water. The solution was dried using anhydrous magnesium sulfate to evaporate the solvent, and the solvent was evaporated. Then, the catalyst and ligand were prepared using column chromatography using silica gel (ethyl acetate: n-hexane = 1: 4 (v: v)). Etc. were removed and the product was separated. The yellow compound thus obtained was recrystallized in a toluene / n-hexane solution to give 5.277 g of the final bis (4-nitro-3-trifluoromethylphenyl) phenylamine (yield 75%).

¹ H NMR (CDCl ₃ , 400.13 MHz, ppm): 7.92 (d, 2H, J = 8.9 Hz); 7.49 (t, 2H, J = 7.7 Hz); 7.43 (d, 1 H, J = 2.5 Hz); 7.38 (tt, 1H, J = 7.6 Hz, J = 1.8 Hz); 7.32 (dd, 2H, J = 8.9 Hz, J = 2.6 Hz); 7.18 (d, 2H, J = 7.3 Hz, J = 2.6 Hz).

¹³ C NMR (CDCl ₃ , 100.62 MHz, ppm): 149.80, 143.62, 142.23, 130.97, 128.01, 127.83, 127.04, 126.04 (q, J = 34.0 Hz), 125.01, 121.52 (q, J = 273.8 Hz), 121.14 (q, J = 5.8 Hz).

Example 1-2: Preparation of 4- [bis (4-nitro-3-trifluoromethylphenyl) amino] benzosulfonate (Formula 1a)

4.000 g (8.49 mmol) of the bis (4-nitro-3-trifluoromethylphenyl) phenylamine prepared above, and 1.92 g (10.18 mmol) of trimethylsilyl chloro sulfonate were dissolved in 40 mL of dichloroethane, followed by 24 at room temperature. Stirred for time. Then, 1.84 g (29.72 mmol) of sodium methoxide was added to the solid state and stirred for 1 hour or more, and then the product was precipitated in excess distilled water to remove the solvent.

The obtained product was recrystallized in ethanol / distilled water solution to give 3.522 g of final 4- [bis (4-nitro-3-trifluoromethylphenyl) amino] benzosulfonate (yield 72%).

¹ H NMR (DMSO-d ₆ , 400.13 MHz, ppm): 8.14 (d, 2H, J = 8.9 Hz); 7.72 (d, 2H, J = 8.4 Hz); 7.55 (d, 2H, J = 2.4 Hz); 7.51 (dd, 2H, J = 8.7 Hz, J = 2.5 Hz); 7.30 (d, 2H, J = 8.4 Hz).

¹³ C NMR (DMSO-d ₆ , 100.62 MHz, ppm): 149.75, 146.99, 143.81, 141.64, 128.40, 128.06, 126.54, 126.40, 123.83 (q, J = 33.3 Hz), 121.84 (q, J = 271.5 Hz) , 121.22 (q, J = 5.7 Hz).

Example 1-3: Sulfonated Poly (arylene Ether Amine) (Formula 5a) Preparation)

0.6008 g (1.05 mmol) of 4- [bis (4-nitro-3-trifluoromethylphenyl) amino] benzosulfonate, 0.2392 g (1.05 mmol) of bisphenol A, and potassium carbonate (K ₂ CO ₃ ) 0.5174 g (3.68 mmol) was dissolved in 4.2 mL dimethylsulfoxide and stirred at 140 ° C. for 1 hour to form a phenoxide salt. At this time, a certain amount of toluene was added to remove water formed during the reaction through an azeotropic process. After the reaction temperature was raised to 180 ° C and stirred for 6 hours, the product was precipitated in distilled water containing a small amount of acetic acid to remove the base and the solvent. The precipitate was filtered, dried, and once again dissolved in a polar aprotic solvent, precipitated and purified in excess of methanol. The precipitated polymer was recovered and dried in vacuo to give a fibrous sulfonated poly (arylene ether amine) (0.52 g; 71% yield).

FTIR (thin film, cm ⁻¹ ): 3041 (aromatic CH); 1595, 1492 (aromatic C = C); 1325 (CN); 1236 (COC); 1165-1135 (CF); 1033, 1002 (S = 0 in SO ₃ H).

¹ H NMR (DMSO-d ₆ , 400.13 MHz, ppm): 7.55 (d, 2H, J = 8.1 Hz); 7.25-7.32 (m, 8 H); 6.97-7.01 (m, 8 H); 1.63 (s, 3 H).

Example 2: Preparation of sulfonated poly (arylene ether amine) (Formula 5b)

0.6340 g (1.06 mmol) of 4- [bis (4-nitro-3-trifluoromethylphenyl) amino] benzosulfonate (Formula 1a) prepared in Example 1, 4,4 ′-(9-fluore) Same method as Example 1-3, except that 0.3875 g (1.06 mmol) of nilidine) -diphenol, 0.5380 g (3.9 mmol) of potassium carbonate (K ₂ CO ₃ ), and 4.0 mL of dimethylsulfoxide were used. To obtain 0.6545 g of fibrous sulfonated poly (arylene ether amine) (Formula 5b) (yield 81%).

FTIR (thin film, cm ⁻¹ ): 3039 (aromatic CH); 1596, 1490 (aromatic C = C); 1325 (CN); 1236 (COC); 1165-1135 (CF); 1034, 1004 (S = 0 in SO ₃ H).

¹ H NMR (DMSO-d ₆ , 400.13 MHz, ppm): 7.92 (d, 2H, J = 7.5 Hz); 7.53 (d, 2H, J = 8.5 Hz); 7.44 (d, 2H, J = 7.5 Hz); 7.40 (t, 2 H, J = 7.3 Hz); 7.31 (t, 2H, J = 7.3 Hz); 7.29 (s, 2 H); 7.25 (d, 2 H, J = 8.8 Hz); 7.14 (d, 4H, J = 8.6 Hz); 6.94-6.99 (m, 8 H).

Example 3: Preparation of sulfonated poly (arylene ether amine) copolymer (Formula 6a)

0.6227 g (1.09 mmol) of 4- [bis (4-nitro-3-trifluoromethylphenyl) amino] benzosulfonate (Formula 1a) prepared in Example 1, and 0.1854 g (0.81 mmol) of bisphenol A, 4 Except for using 0.0961 g (0.27 mmol) of 4 '-(9-fluorenyridine) -diphenol, 0.6380 g (4.38 mmol) of potassium carbonate (K ₂ CO ₃ ), and 3.8 mL of dimethylsulfoxide. In the same manner as in Example 1-3, 0.59 g of a fibrous sulfonated poly (arylene ether amine) copolymer (Formula 6a) was obtained (yield 72%).

FTIR (thin film, cm ⁻¹ ): 3039 (aromatic CH); 1596, 1490 (aromatic C = C); 1325 (CN); 1236 (COC); 1165-1135 (CF); 1034, 1004 (S = 0 in SO ₃ H).

¹ H NMR (DMSO-d ₆ , 400.13 MHz, ppm): shown in FIG. 1.

Example 4: Preparation of sulfonated poly (arylene ether amine) copolymer (Formula 6b)

0.5971 g (1.04 mmol) of 4- [bis (4-nitro-3-trifluoromethylphenyl) amino] benzosulfonate (Formula 1a) prepared in Example 1, 0.1754 g (0.77 mmol) of bisphenol A, 3 Same as Example 1-3, except that 0.0421 g (0.27 mmol) of 5-5-dihydroxy benzoic acid, 0.5135 g (3.65 mmol) of potassium carbonate (K ₂ CO ₃ ), and 3.5 mL of dimethylsulfoxide were used. The process was carried out to obtain 0.55 g of fibrous sulfonated poly (arylene ether amine) copolymer (Formula 6b) (yield 66%).

FTIR (thin film, cm ⁻¹ ): 3039 (aromatic CH); 1707 (C═O in COOH); 1596, 1490 (aromatic C = C); 1325 (CN); 1236 (COC); 1165-1135 (CF); 1034, 1004 (S = 0 in SO ₃ H).

¹ H NMR (DMSO-d ₆ , 400.13 MHz, ppm): shown in FIG. 2.

Example 5: Preparation of sulfonated poly (arylene ether amine) copolymer (Formula 7a)

0.4219 g (0.74 mmol) of 4- [bis (4-nitro-3-trifluoromethylphenyl) amino] benzosulfonate prepared in Example 1, 0.2093 g (0.92 mmol) of bisphenol A, 3,3'- Except that 0.0890 g (0.18 mmol) of disulfonate-4,4'-dichlorodiphenylsulfone, 0.4565 g (3.25 mmol) of potassium carbonate (K ₂ CO ₃ ), and 3.2 mL of dimethylsulfoxide were used. In the same manner as in Example 1-3, 0.45 g of a fibrous sulfonated poly (arylene ether amine) copolymer (Formula 7a) was obtained (yield 71%).

FTIR (thin film, cm ⁻¹ ): 3039 (aromatic CH); 1560, 1488 (aromatic C = C); 1326 (CN); 1235 (COC); 1162-1135 (CF); 1033, 1002 (S = 0 in SO ₃ H).

¹ H NMR (DMSO-d ₆ , 400.13 MHz, ppm): shown in FIG. 3.

Example 6: Preparation and Hydrogen Substitution of Sulfonate Poly (arylene Ether Amine) Polymer Electrolyte Membrane

The sulfonated poly (arylene ether amine) polymer containing the sulfonate in the form of sodium sulfate prepared in Example 1 was completely dissolved in dimethylacetamide (DMAc), followed by a filter (0.45 μm).

Subsequently, the solution was poured onto a glass plate, and then the solution was applied onto the glass plate using a doctor blade to a thickness of several micrometers to several tens of micrometers. At this time, the concentration of the sulfonate poly (arylene ether amine) polymer solution is preferably 10% (w / v). The solution-coated glass plate was placed in a vacuum oven, gradually raised to 80 ° C. at room temperature, dried for 24 hours, and further dried in a vacuum oven maintained at 110 ° C. for 24 hours. Thereafter, the formed film was separated from the glass plate.

The obtained membrane was added to an aqueous hydrochloric acid solution or an aqueous sulfuric acid solution to replace the sulfonic acid salt with a sulfonic acid, thereby preparing a novel sulfonated poly (arylene ether amine) polymer electrolyte membrane containing sulfonic acid. At this time, the treatment concentration of the aqueous hydrochloric acid solution or sulfuric acid aqueous solution was 1 M, the treatment time was 24 hours.

Examples 7-10: Preparation of Sulfonate Poly (arylene Ether Amine) Polymer Electrolyte Membrane and Hydrogen Replacement

The sulfonated poly (arylene ether amine) in the same manner as in Example 6, except that each of the sulfonated poly (arylene ether amine) polymers containing sulfonate in the form of sodium sulfate prepared in Examples 2 to 5 was used. ) A polymer electrolyte membrane was prepared.

Experimental Example 1: Solubility of Sulfonate Poly (arylene Ether Amine)

The solubility of the novel sulfonated poly (arylene ether amine) polymer containing sodium sulfonate prepared in Examples 1 to 5 is summarized in Table 1 below.

m- cresol DMSO DMF DMAc NMP Example 1 + + + + + Example 2 + + + + + Example 3 + + + + + Example 4 + + + + + Example 5 + + + + + [Note] Solubility +: full recording at room temperature

Experimental Example 2: Ion Exchange Capacity Measurement of Electrolyte Membrane

0.1 g of each of the sulfonated poly (arylene ether amine) polymer electrolyte membranes prepared in Examples 6 to 10 was immersed in a 50 ml solution of NaCl for 10 hours or more to convert hydrogen ions (H ⁺ ) into sodium ions (Na ⁺ ). Substituted. The substituted hydrogen ions (H ⁺ ) are titrated with 0.025M NaOH standard solution, and the IEC (Ion Exchange Capacity) value of the polymer membrane is calculated according to Equation 1 as the amount of NaOH used for the titration, and the results are as follows. Table 2 shows.

At this time, the IEC value of Nafion 115 manufactured by DuPont was used as comparison data.

[Equation 1]

IEC (-SO ₃ H mequiv./g) = ( V _NaOH C _NaOH ) / W _dry

In Equation 1, W _dry : weight of the dried thin film (g), V _NaOH : consumed NaOH standard solution (mL), C _NaOH : NaOH standard solution concentration (M).

Experimental Example 3: Measurement of Water Absorption Rate and Swelling Ratio of Electrolyte Membrane

After each of the sulfonated poly (arylene ether amine) polymer electrolyte membranes prepared in Examples 6 to 10 was hydrated in distilled water at room temperature for 12 hours or more, water on the surface of the membrane was removed and the weight and thickness of the membrane were measured. . Then, after drying for 12 hours or more in a vacuum oven at 100 ℃, the weight and thickness of the dried membrane was measured, and the water absorption and swelling ratio of the membrane was measured according to the following equations (2) and (3). The results are shown in Table 2 below.

[Equation 2]

Water absorption rate (%) = ( W _wet - W _dry ) / W _dry ｘ 100

In Equation 2, W _dry : weight of dried thin film (g), W _wet : weight of adsorbed thin film (g)

[Equation 3]

Swelling Ratio (%) = ( l _wet - l _dry ) / l _dry ｘ 100

In Equation 3, l _dry : thickness of dried thin film (μm), l _wet : thickness of adsorbed thin film (μm).

IEC (mequiv./g) Water absorption rate (%) Swelling Ratio (%) Example 6 0.85 5.0 4.5 Example 7 0.82 12.6 3.4 Example 8 0.89 25.7 11.1 Example 9 1.18 28.5 12.5 Example 10 1.52 86.8 14.7

Experimental Example 4 Measurement of Hydrogen Ion Conductivity of Electrolyte Membrane

The hydrogen ion conductivity of the poly (arylene ether amine) polymer membrane prepared in Examples 6 to 10 was measured. In the measurement of the hydrogen ion conductivity, the impedance was measured by a dipole method by an alternating current impedance measurement method at a temperature of 40 to 100 ° C., and the hydrogen ion conductivity was measured by calculating the following equation (4). It is shown in Table 3 below.

[Equation 4]

σ = L / RS

In Equation 4, σ: conductivity (S / cm), R: resistance (Ω), L: distance between electrodes (cm), and S: effective surface area (cm 2) through which current flows.

In order to compare the hydrogen ion conductivity of the poly (arylene ether amine) polymer membrane containing the sulfonic acid group developed in the present invention, Nefion 115 (Nafion 115, a perfluorinated sulfonic acid polymer), a trade name of DuPont, USA, which is currently commercialized Membrane was used. Hydrogen ion conductivity for Nepion 115 was measured in the same manner as mentioned above, and the results are shown in Table 3 below.

division Example 6 Example 7 Example 8 Example 9 Example 10 Nefion112 Hydrogen ion conductivity 40 ℃ 0.0002 0.0003 0.0008 0.0013 0.0075 0.0080 50 ℃ 0.0002 0.0003 0.0009 0.0014 0.0076 0.0088 60 ℃ 0.0003 0.0003 0.0010 0.0015 0.0082 0.0103 70 ℃ 0.0003 0.0004 0.0010 0.0016 0.0094 0.0120 80 ℃ 0.0003 0.0004 0.0011 0.0022 0.0095 0.0146 90 ℃ 0.0003 0.0005 0.0012 0.0037 0.0099 0.0190 100 ℃ 0.0004 0.0005 0.0013 0.0055 0.0110 0.0231

As shown in Table 1 to Table 3, the sulfonated poly (arylene ether amine) electrolyte membrane prepared in Examples 6 to 10 according to the present invention is a polymer having high molecular weight as a transparent and tough quality electrolyte membrane. In addition, due to the introduction of the trifluoromethyl substituent, it showed a significantly lower water absorption and swelling ratio than the known sulfonated poly (arylene ether). In particular, it was confirmed that the sulfonated poly (arylene ether amine) electrolyte membrane of Example 10 showed equivalent hydrogen ion conductivity as compared to the nefion used in the conventional polymer membrane.

From this, it was predicted that the sulfonated poly (arylene ether amine) prepared according to the present invention would be effectively applied to ion exchange membranes for fuel cells.

The electrolyte membrane according to the present invention has not only high hydrogen ion conductivity but also excellent mechanical properties and chemical stability, and can control the distribution, position, number, etc. of sulfonic acid groups in the polymer skeleton, There is no deterioration of the film properties, thereby effectively producing a thin film.

Claims (13)

Sulfonated triphenylamine derivatives represented by Formula 1 below: [Formula 1]

In Formula 1, X ¹ and X ² are each independently selected from -NO ₂ , -F, -Cl, -Br and -I; M ¹ is selected from -H, -Na, and -K. A polymer prepared using the sulfonated triphenylamine derivative of claim 1. The polymer according to claim 2, wherein the polymer is a sulfonated poly (arylene ether amine) including a repeating unit represented by the following Chemical Formula 2: [Formula 2]

In Formula 2, M ¹ is selected from -H, -Na, and -K; R ¹ is selected from arylene, alkylene and hybrid functional groups thereof. The method of claim 3, wherein the polymer is a sulfonated poly (arylene ether amine) further comprising a repeating unit selected from the group consisting of a repeating unit represented by the following formula (3) and a repeating unit represented by the following formula (4) Characteristic Polymers: [Formula 3]

In Formula 3, M ¹ is selected from -H, -Na and -K; R ² is not the same as R ¹ and is selected from arylene, alkylene and hybrid functional groups thereof; [Formula 4]

In Formula 4, M ² is selected from -H, -Na and -K; Y is -S (= 0) ₂ -or -C (= 0)-; R ³ is selected from arylene, alkylene and hybrid functional groups thereof. According to claim 2, wherein the polymer is a sulfonated poly (arylene ether amine) represented by the formula (5), sulfonated poly (arylene ether amine) represented by the formula (6) and sulfonated poly represented by the formula (7) (Arylene ether amine) is characterized in that the polymer is selected from the group consisting of: [Formula 5]

In Formula 5, M ¹ is selected from -H, -Na, and -K; R ¹ is selected from arylene, alkylene and hybrid functional groups thereof; n is an integer from 5 to 200; [Formula 6]

In Formula 6, M ¹ is selected from -H, -Na, and -K; R ¹ and R ² are different from each other and are each independently selected from arylene, alkylene and hybrid functional groups thereof; n and m are each independently an integer from 5 to 200; [Formula 7]

In Formula 7, M ¹ and M ² are each independently selected from -H, -Na, and -K; Y is -S (= 0) ₂ -or -C (= 0)-; R ¹ and R ³ are each independently selected from arylene, alkylene and hybrid functional groups thereof; n and m are each independently an integer of 5 to 200. The polymer according to claim 2, wherein the sulfonated triphenylamine derivative and the diol derivative are prepared by nucleophilic aromatic substitution reaction. The polymer according to claim 2, wherein the sulfonated triphenylamine derivative, diol derivative and base are dissolved in a polar aprotic solvent and prepared by nucleophilic aromatic substitution. The polymer of claim 6, wherein the polymer is prepared by further reacting a comonomer together. The method of claim 7, wherein the polar aprotic solvent is dimethyl sulfoxide (DMSO), N-methylpyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone (DMI), dimethylacetamide (DMAc ), Dimethylformamide (DMF), and tetramethylene sulfone, characterized in that at least one member selected from the group consisting of polymers. 8. The polymer of claim 7, wherein the sulfonated triphenylamine derivative and the diol derivative are each used at a concentration of 15 to 35 M% with respect to the polar aprotic solvent. The method of claim 7, wherein the base is at least one selected from the group consisting of potassium carbonate (K ₂ CO ₃ ) and cesium carbonate (Cs ₂ CO ₃ ), 0.1 to 5 equivalents to the sulfonated triphenylamine derivative Polymer is characterized by being used as. An electrolyte membrane comprising the polymer of any one of claims 2 to 11. A fuel cell using the membrane electrode assembly comprising the electrolyte membrane of claim 12.

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