KR20140142036A - Polybenzimidasole nano-composite membrane using amine group-containing silsesquioxane, preparing method of the same, and fuel cell including the same - Google Patents

Abstract

The present invention relates to a polybenzimidazole nano-composite membrane using silsesquioxane containing a amine group; a method for manufacturing the same; and a fuel cell including the same. The polybenzimidazole nano-composite membrane includes: a benzimidazole-based polymer; and polyhedral oligomeric silsesquioxane represented by Chemical Formula 1. According to the present invention, an electrolyte membrane for a high molecular electrolyte fuel cell which can be used at high temperatures of 120-200°C under a non-humidified condition can be manufactured.

Description

TECHNICAL FIELD [0001] The present invention relates to a polybenzimidazole nanocomposite membrane using amine group-containing silsesquioxane, a process for producing the same, and a fuel cell comprising the same. INCLUDING THE SAME}

The present invention relates to a polybenzimidazole nanocomposite membrane using amine group-containing silsesquioxane, a process for producing the polybenzimidazole nanocomposite membrane, and a fuel cell comprising the polybenzimidazole nanocomposite membrane.

A fuel cell is a power generation system that directly converts energy generated by electrochemically reacting a fuel and an oxidant into electrical energy. With the recent environmental problems, depletion of energy sources, commercialization of fuel cell vehicles, development of high performance fuel cells which can operate at high temperatures with high energy efficiency and reliability is highly demanded. In order to increase the efficiency of the fuel cell as described above, development of a polymer membrane that can be used at a high temperature is also required.

A fuel cell using a polymer electrolyte membrane as an electrolyte, that is, a PEMFC (Polymer Electrolyte Membrane Fuel Cell), is expected to be a power source for an electric vehicle or a distributed power generation system for home use because its operating temperature is relatively low and can be downsized . As the polymer electrolyte membrane, a perfluorocarbon-sulfonic acid-based polymer membrane typified by Nafion (registered trademark) is used.

However, in order for this type of polymer electrolyte membrane to exhibit proton conduction, moisture is required and therefore humidification is required. Further, in order to increase the efficiency of the battery system, high temperature operation at a temperature of 100 캜 or more is required, but at this temperature, moisture in the electrolyte membrane evaporates and becomes depleted, and the function as a solid electrolyte is lost.

In order to solve the problems caused by these conventional techniques, a non-humidified electrolyte membrane capable of operating at a high temperature of 100 DEG C or more without humidification has been developed. For example, JP-A-11-503262 discloses a material such as polybenzimidazole (PBI) doped with phosphoric acid as a constituent material of a moisture-free electrolyte membrane.

However, the PBI / phosphate doping membrane, which is currently used as a PEMFC electrolyte membrane for high temperature (100 ° C to 200 ° C), is a doped membrane rather than a chemically bonded phosphate group. Has a problem of degradation.

In order to increase the amount of phosphoric acid and to solve the problem of leakage of phosphoric acid, research is being conducted to combine amine-group (-NH ₂ ) -containing particles capable of capturing phosphoric acid with a polymer electrolyte membrane. However, Complexation was achieved using inorganic particles of several tens to several hundred nanometers in size. Therefore, there is a problem that the inorganic particles may interfere with the movement of protons during complexing.

PBI has very good mechanical strength (> 40 MPa) before doping, but has a problem (< 5 MPa) that the strength decreases rapidly after doping with phosphoric acid. The effect is insufficient and the mechanical strength of the composite membrane is decreased due to the particle size and the aggregation phenomenon.

The present invention provides a polybenzimidazole nanocomposite membrane using an amine group-containing silsesquioxane, a method for producing the polybenzimidazole nanocomposite membrane, and a fuel cell including the polybenzimidazole nanocomposite membrane.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

According to a first aspect of the present invention, there is provided a polymer electrolyte fuel cell comprising: a benzimidazole-based polymer; And a polyhedral oligomeric silsesquioxane represented by the following general formula (1): &lt; EMI ID = 1.0 &gt;

[Chemical Formula 1]

;

;

In Formula 1,

R is an amine group-containing substituent.

The second aspect of the present invention includes preparing a benzimidazole-based polymer / silsesquioxane nanocomposite membrane by mixing a polyhedral oligomeric silsesquioxane substituted with an amine group-containing substituent and a benzimidazole-based polymer The present invention also provides a method for producing a polybenzimidazole nanocomposite membrane using an amine group-containing silsesquioxane.

A third aspect of the present invention provides a fuel cell comprising a polybenzimidazole nanocomposite membrane using an amine group-containing silsesquioxane according to the first aspect of the present invention.

According to the present invention, it is possible to produce an electrolyte membrane for a polymer electrolyte fuel cell which can be utilized at a high temperature of about 120 ° C to about 200 ° C under non-humidified conditions by bonding an amine group to the Si terminal of the polyhedral oligomeric silsesquioxane. The present invention relates to polyhedral oligomeric silsesquioxane which can bind to an amine group at the Si terminal and capture phosphoric acid which is liable to leak, thereby increasing the amount of phosphoric acid in the polymer electrolyte membrane and preventing leakage of phosphoric acid, Overcoming the problems of peripheral corrosion and performance degradation and at the same time by forming nanocomposite films with nanometer size levels of less than about 10 nm which are much smaller than those of inorganic nanoparticles used in conventional composites from tens of nanometers to several hundreds of nanometers The proton conductivity can be improved and the mechanical strength can be enhanced.

In particular, the present invention is expected to contribute to the cost reduction of the fuel cell because the mechanical strength is maintained even if the thickness of the nanocomposite membrane is reduced.

FIG. 1 is a graph showing changes in the amount of phosphoric acid doped over time in the phosphoric acid doping of the polybenzimidazole membrane of the comparative example and the nanocomposite membrane according to one embodiment of the present invention. FIG.
2 is a graph showing the proton conductivity of the polybenzimidazole membrane of the comparative example and the nanocomposite membrane according to one embodiment of the present invention.
3 is a graph showing the mechanical strength and tensile modulus of the polybenzimidazole film of the comparative example and the nanocomposite film according to one embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, the same reference numbers are used throughout the specification to refer to the same or like parts.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is "on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as "including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise.

The terms "about "," substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure.

The word " step (or step) "or" step "used to the extent that it is used throughout the specification does not mean" step for.

Throughout this specification, the term "combination (s) thereof " included in the expression of the machine form means a mixture or combination of one or more elements selected from the group consisting of the constituents described in the expression of the form of a marker, Quot; means at least one selected from the group consisting of the above-mentioned elements.

Throughout this specification, the description of "A and / or B" means "A or B, or A and B".

Hereinafter, exemplary embodiments have been described in detail with reference to the drawings, but the present invention is not limited thereto.

According to a first aspect of the present invention, there is provided a polymer electrolyte fuel cell comprising: a benzimidazole-based polymer; And a polyhedral oligomeric silsesquioxane represented by the following general formula (1): &lt; EMI ID = 1.0 &gt;

 [Chemical Formula 1]

;

;

In Formula 1,

R is an amine group-containing substituent.

The polyhedral ooligomeric silsesquioxane (POSS) according to the present invention comprises a polyhedral oligomeric silsesquioxane having a cage structure as shown in Formula 1, and the polyhedral oligomeric silsesquioxane The nanocomposite membrane was prepared using an amine group-containing silsesquioxane.

,

, 및 이들의 이성질체들로 이루어진 군으로부터 선택되는 것을 포함하는 것일 수 있으나, 이에 제한되지 않을 수 있다. 본원에 따른 아민기-함유 치환기에 의하여 치환된 다면체 올리고머형 실세스퀴옥산은 케이지 구조의 다면체 올리고머형 실세스퀴옥산에 1 개, 2 개, 또는 3 개의 아민기 (-NH₂)를 포함하는 치환기 (R)가 화학적으로 결합된 것이다.According to one embodiment, the amine group-containing substituent is selected from the group consisting of -NH ₂ , -O-NH ₂ , -R-NH ₂ , - (CH ₂ ) _n -NH ₂ (n is an integer of 1 to 20) ,

,

, And isomers thereof, but the present invention is not limited thereto. The polyhedral oligomeric silsesquioxanes substituted by an amine group-containing substituent according to the present invention may include one, two, or three amine groups (-NH ₂ ) on the polyhedral oligomeric silsesquioxane of the cage structure The substituent (R) is chemically bonded.

The present invention relates to a polyhedral oligomeric silsesquioxane which can bind an amine group to the Si terminal and capture the phosphoric acid which is liable to leak. Therefore, it is possible to increase the amount of phosphoric acid capable of transferring protons in the polymer electrolyte membrane, Helping to improve proton conductivity. In addition, the polybenzimidazole nanocomposite membrane using the amine group-containing silsesquioxane according to the present invention can prevent the leakage of phosphoric acid and maintain the performance of the polymer / phosphate system for a long term. Phosphoric acid transports protons through self-dissociation in a fuel cell. If the phosphoric acid is trapped using an amine group, the proton can be effectively transferred without the leakage of phosphoric acid.

,

,

,

, 및 이들의 이성질체들로 이루어진 군으로부터 선택되는 것을 포함하는 것일 수 있으나, 이에 제한되지 않을 수 있다. 상기 n은 1 내지 20의 정수이다.According to one embodiment of the present invention, the benzimidazole-based polymer may include, but is not limited to, those selected from the group consisting of polybenzimidazole and derivatives thereof. For example, the above-mentioned benzimidazole-based polymer can be produced,

,

,

,

, And isomers thereof, but the present invention is not limited thereto. Wherein n is an integer of 1 to 20;

According to one embodiment of the present invention, the benzimidazole-based polymer may include, but not limited to, those having a molecular weight of about 5,000 to about 1,000,000. For example, the benzimidazole-based polymer may have a molecular weight of about 5,000 to about 15,000, about 10,000 to about 50,000, about 25,000 to about 75,000, about 50,000 to about 100,000, about 75,000 to about 125,000, about 100,000 to about 150,000, From about 200,000 to about 250,000, from about 225,000 to about 275,000, from about 250,000 to about 300,000, from about 275,000 to about 325,000, from about 300,000 to about 350,000, from about 325,000 to about 300,000, from about 300,000 to about 350,000, from about 125,000 to about 175,000, from about 150,000 to about 200,000, from about 175,000 to about 225,000, About 450,000 to about 500,000, about 475,000 to about 525,000, about 500,000 to about 550,000, about 525,000 to about 575,000, about 450,000 to about 500,000, about 450,000 to about 500,000, about 500,000 to about 550,000, about 525,000 to about 575,000, about 375,000, about 350,000 to about 400,000, about 375,000 to about 425,000, about 400,000 to about 450,000, , About 550,000 to about 600,000, about 575,000 to about 625,000, about 600,000 to about 650,000, about 625,000 to about 675,000, about 650,000 to about 700,000, about 675,000 to about 725,000, about 700,000 From about 875,000 to about 875,000, from about 850,000 to about 900,000, from about 875,000 to about 925,000, from about 900,000 to about 8000, from about 800,000 to about 850,000, from about 825,000 to about 875,000, from about 875,000 to about 900,000, from about 875,000 to about 925,000, from about 900,000 to about 8000, from about 750,000 to about 775,000, from about 750,000 to about 800,000, 950,000, from about 925,000 to about 975,000, from about 950,000 to about 1,000,000, or from about 975,000 to about 1,000,000.

According to one embodiment of the present invention, the polyhedral oligomeric silsesquioxane may have a size of nanometer level, but the present invention is not limited thereto. The polyhedral oligomeric silsesquioxane according to the present invention may be, but is not limited to, a particle material having a size of a few nm, for example, less than about 10 nm. For example, the size of the polyhedral oligomeric silsesquioxane particles may range from about 0.1 nm to about 1 nm, from about 0.5 nm to about 2 nm, from about 1 nm to about 3 nm, from about 2 nm to about 3 nm, From about 2 nm to about 4 nm, from about 3 nm to about 5 nm, from about 4 nm to about 6 nm, from about 5 nm to about 7 nm, from about 6 nm to about 8 nm, from about 7 nm to about 9 nm, To about 9.9 nm, or from about 9 nm to about 9.9 nm. The nanometer level size of the polyhedral oligomeric silsesquioxane does not interfere with the proton transfer during the production of the proton conducting polymer composite membrane and thus can realize excellent proton conductivity as well as forming a nanocomposite membrane at the molecular level, The mechanical strength and tensile strength of the film can be enhanced.

According to one embodiment of the present invention, the polyhedral oligomeric silsesquioxane may include about 1 to about 16 amine groups, but the present invention is not limited thereto. For example, at the Si terminus of the polyhedral oligomeric silsesquioxane, about 1 to about 16, about 2 to about 16, about 3 to about 16, about 4 to about 16, and about From about 5 to about 16, from about 6 to about 16, from about 7 to about 16, from about 8 to about 16, from about 9 to about 16, from about 10 to about 16, from about 11 From about 120 DEG C to about 200 DEG C by introducing about 16, about 12 to about 16, about 13 to about 16, about 14 to about 16, or about 15 to about 16 amine groups, ) Can also achieve an increase in proton conductivity.

According to one embodiment of the present invention, the polyhedral oligomeric silsesquioxane substituted by the amine group-containing substituent may be contained in an amount of about 1% by weight to about 50% by weight based on the benzimidazole-based polymer, But may not be limited thereto. For example, the polyhedral oligomeric silsesquioxane substituted with an amine group-containing substituent may be present in an amount of from about 1% to about 5% by weight, from about 1% to about 10% by weight, based on the benzimidazole- %, About 5 wt% to about 15 wt%, about 10 wt% to about 20 wt%, about 15 wt% to about 25 wt%, about 20 wt% to about 30 wt% %, About 30 wt% to about 40 wt%, about 35 wt% to about 45 wt%, about 40 wt% to about 50 wt%, or about 45 wt% to about 50 wt% , But may not be limited thereto.

According to one embodiment of the present invention, mechanical strength may be maintained even if the thickness of the nanocomposite membrane is reduced, but the present invention is not limited thereto.

The second aspect of the present invention includes preparing a benzimidazole-based polymer / silsesquioxane nanocomposite membrane by mixing a polyhedral oligomeric silsesquioxane substituted with an amine group-containing substituent and a benzimidazole-based polymer The present invention also provides a method for producing a polybenzimidazole nanocomposite membrane using an amine group-containing silsesquioxane.

,

, 및 이들의 이성질체들로 이루어진 군으로부터 선택되는 것을 포함하는 것일 수 있으나, 이에 제한되지 않을 수 있다. 본원에 따른 아민기-함유 치환기에 의하여 치환된 다면체 올리고머형 실세스퀴옥산은 케이지 구조의 다면체 올리고머형 실세스퀴옥산에 1 개, 2 개, 또는 3 개의 아민기 (-NH₂)를 포함하는 치환기 (R)가 화학적으로 결합된 것이다.According to one embodiment, the amine group-containing substituent is selected from the group consisting of -NH ₂ , -O-NH ₂ , -R-NH ₂ , - (CH ₂ ) _n -NH ₂ (n is an integer of 1 to 20) ,

,

, And isomers thereof, but the present invention is not limited thereto. The polyhedral oligomeric silsesquioxanes substituted by an amine group-containing substituent according to the present invention may include one, two, or three amine groups (-NH ₂ ) on the polyhedral oligomeric silsesquioxane of the cage structure The substituent (R) is chemically bonded.

The present invention relates to a polyhedral oligomeric silsesquioxane which can bind an amine group to the Si terminal and capture the phosphoric acid which is liable to leak. Therefore, it is possible to increase the amount of phosphoric acid capable of transferring protons in the polymer electrolyte membrane, Helping to improve proton conductivity. In addition, the polybenzimidazole nanocomposite membrane using the amine group-containing silsesquioxane according to the present invention can prevent the leakage of phosphoric acid and maintain the performance of the polymer / phosphate system for a long term. Phosphoric acid transports protons through self-dissociation in a fuel cell. If the phosphoric acid is trapped using an amine group, the proton can be effectively transferred without the leakage of phosphoric acid.

,

,

,

, 및 이들의 이성질체들로 이루어진 군으로부터 선택되는 것을 포함하는 것일 수 있으나, 이에 제한되지 않을 수 있다. 상기 n은 1 내지 20의 정수이다.According to one embodiment of the present invention, the benzimidazole-based polymer may include, but is not limited to, those selected from the group consisting of polybenzimidazole and derivatives thereof. For example, the above-mentioned benzimidazole-based polymer can be produced,

,

,

,

, And isomers thereof, but the present invention is not limited thereto. Wherein n is an integer of 1 to 20;

According to one embodiment of the present invention, the benzimidazole-based polymer may include, but not limited to, those having a molecular weight of about 5,000 to about 1,000,000. For example, the benzimidazole-based polymer may have a molecular weight of about 5,000 to about 15,000, about 10,000 to about 50,000, about 25,000 to about 75,000, about 50,000 to about 100,000, about 75,000 to about 125,000, about 100,000 to about 150,000, From about 200,000 to about 250,000, from about 225,000 to about 275,000, from about 250,000 to about 300,000, from about 275,000 to about 325,000, from about 300,000 to about 350,000, from about 325,000 to about 300,000, from about 300,000 to about 350,000, from about 125,000 to about 175,000, from about 150,000 to about 200,000, from about 175,000 to about 225,000, About 450,000 to about 500,000, about 475,000 to about 525,000, about 500,000 to about 550,000, about 525,000 to about 575,000, about 450,000 to about 500,000, about 450,000 to about 500,000, about 500,000 to about 550,000, about 525,000 to about 575,000, about 375,000, about 350,000 to about 400,000, about 375,000 to about 425,000, about 400,000 to about 450,000, , About 550,000 to about 600,000, about 575,000 to about 625,000, about 600,000 to about 650,000, about 625,000 to about 675,000, about 650,000 to about 700,000, about 675,000 to about 725,000, about 700,000 From about 875,000 to about 875,000, from about 850,000 to about 900,000, from about 875,000 to about 925,000, from about 900,000 to about 8000, from about 800,000 to about 850,000, from about 825,000 to about 875,000, from about 875,000 to about 900,000, from about 875,000 to about 925,000, from about 900,000 to about 8000, from about 750,000 to about 775,000, from about 750,000 to about 800,000, 950,000, from about 925,000 to about 975,000, from about 950,000 to about 1,000,000, or from about 975,000 to about 1,000,000.

According to one embodiment of the present invention, the polyhedral oligomeric silsesquioxane may have a size of nanometer level, but the present invention is not limited thereto. The polyhedral oligomeric silsesquioxane according to the present invention may be, but is not limited to, a particle material having a size of a few nm, for example, less than about 10 nm. For example, the size of the polyhedral oligomeric silsesquioxane particles may range from about 0.1 nm to about 1 nm, from about 0.5 nm to about 2 nm, from about 1 nm to about 3 nm, from about 2 nm to about 3 nm, From about 2 nm to about 4 nm, from about 3 nm to about 5 nm, from about 4 nm to about 6 nm, from about 5 nm to about 7 nm, from about 6 nm to about 8 nm, from about 7 nm to about 9 nm, To about 9.9 nm, or from about 9 nm to about 9.9 nm. The nanometer level size of the polyhedral oligomeric silsesquioxane does not interfere with the proton transfer during the production of the proton conducting polymer composite membrane and thus can realize excellent proton conductivity as well as forming a nanocomposite membrane at the molecular level, The mechanical strength and tensile strength of the film can be enhanced.

According to one embodiment of the present invention, the polyhedral oligomeric silsesquioxane may include about 1 to about 16 amine groups, but the present invention is not limited thereto. For example, at the Si terminus of the polyhedral oligomeric silsesquioxane, about 1 to about 16, about 2 to about 16, about 3 to about 16, about 4 to about 16, and about From about 5 to about 16, from about 6 to about 16, from about 7 to about 16, from about 8 to about 16, from about 9 to about 16, from about 10 to about 16, from about 11 From about 120 DEG C to about 200 DEG C by introducing about 16, about 12 to about 16, about 13 to about 16, about 14 to about 16, or about 15 to about 16 amine groups, ) Can also achieve an increase in proton conductivity.

According to one embodiment of the present invention, the polyhedral oligomeric silsesquioxane substituted by the amine group-containing substituent may be added in an amount of about 1% by weight to about 50% by weight based on the benzimidazole-based polymer, But may not be limited thereto. For example, the polyhedral oligomeric silsesquioxane substituted with an amine group-containing substituent may be present in an amount of from about 1% to about 5% by weight, from about 1% to about 10% by weight, based on the benzimidazole- %, About 5 wt% to about 15 wt%, about 10 wt% to about 20 wt%, about 15 wt% to about 25 wt%, about 20 wt% to about 30 wt% %, About 30 wt% to about 40 wt%, about 35 wt% to about 45 wt%, about 40 wt% to about 50 wt%, or about 45 wt% to about 50 wt% But may not be limited.

According to an embodiment of the present invention, the method may further include doping the benzimidazole-based polymer / silsesquioxane nanocomposite membrane by phosphoric acid, but the present invention is not limited thereto. The phosphoric acid is a substance that moves the proton through its own dissociation in the fuel cell. The amount of phosphoric acid in the benzimidazole-based polymer / silsesquioxane nanocomposite membrane can be increased through the doping, have.

According to one embodiment of the present invention, the doping with the phosphoric acid may include, but is not limited to, the above-mentioned operation in which the benzimidazole-based polymer / silsesquioxane nanocomposite membrane is immersed in a phosphoric acid solution.

A third aspect of the present invention provides a fuel cell comprising a polybenzimidazole nanocomposite membrane using an amine group-containing silsesquioxane according to the first aspect of the present invention.

The fuel cell is an electrochemical device that converts the chemical energy of fuel directly into electrical energy and provides a clean and highly efficient source of electrical energy, potentially electrical vehicle power. Like a battery, a fuel cell may consist of, but is not limited to, two electrodes separated by an electrolyte made of a thin polymer membrane. However, unlike a battery, a fuel cell according to the present invention can generate electricity for a prolonged period of time in which protons continue to flow through the phosphoric acid.

In the fuel cell according to the third aspect of the present invention, a detailed description of parts overlapping with the first aspect of the present invention is omitted, but the description of the first aspect of the present invention is omitted in the third aspect of the present invention The same can be applied.

Hereinafter, preferred embodiments of the present invention will be described. However, the following examples are given only for the sake of understanding the present invention, and the present invention is not limited to the following examples.

[Example]

Production Example 1 On the nitro  Substituted POSS Manufacturing

5 g of octa (phenyl) polyhedral oligomeric silsesquioxane [Octa (phenyl) POSS] was dissolved in 30 mL of fuming nitric acid and reacted at room temperature for 20 hours. A precipitate was formed by adding the reaction solution to ice water. The precipitate was filtered and repeatedly washed with water several times to remove unreacted fuming nitric acid, thereby obtaining a powder. The obtained powder was washed with 20 mL of ethanol, filtered, and then dried at room temperature to obtain octa (nitrophenyl) POSS having a nitro group.

Production Example 2 In the amine group  Substituted POSS ( POSS -N)

1 g of octa (nitrophenyl) POSS obtained in Preparation Example 1 and 0.12 g of Pd / C catalyst (5 wt%) were dissolved in a mixed solvent of 40 mL of tetrahydrofuran (THF) and 40 mL of triethylamine, And heated at 40 占 폚 for 1 hour. 3 mL of formic acid (85%) was added dropwise to the reaction solution under heating. At this time, when it was confirmed that the reaction solution was separated into two layers, the temperature was raised to 60 캜 and heated for 5 hours. The THF layer in the layered solution was removed, and the remaining solution was filtered using a celite filter. 100 mL of ethyl acetate (EA) was added to the filtrate obtained through filtration, and 100 mL of deionized water was further added to the filtrate, and then the EA solution layer was separated. At this time, the deionized water washing was repeated four times. The crystals were obtained by adding 1 L of hexane to the separated EA layer and standing. The obtained crystals were dried at room temperature for one day to obtain a polyhedral oligomeric silsesquioxane (hereinafter referred to as POSS-N) substituted by an amine group.

Preparation Example 3. Preparation of polybenzimidazole ( PBI ) Manufacture of Powder

In a 250 mL round flask, 0.2678 g (1.25 mmol) of 3,3'-diaminobenzidine (DAB) was dissolved in 12.6 g of polyphosphoric acid (PPA). To the solution, 0.4903 g (1.25 mmol) of 2,2-bis (4-carboxyphenyl) hexafluoropropane was added and reacted at 200 ° C. for 24 hours to obtain a sticky &Lt; / RTI &gt; The sticky solution prepared above was dropwise added dropwise to 1 L of deionized water being stirred. When the precipitated polymer was produced, the polymer was filtered, washed with deionized water about 5 times, and the washed polymer was placed in a vacuum oven at 100 ° C and dried to obtain a PBI powder.

Production Example 4. Preparation of polybenzimidazole ( PBI ) Preparation of membranes

A PBI solution was prepared by dissolving PBI powder obtained in Preparation Example 3 in dimethylacetamide (DMAc) at a ratio of 1: 19. 20 g of the PBI solution was transferred to a glass chalet and placed in an oven at 80 ° C, and then the oven temperature was slowly raised to 190 ° C and cast for 24 hours. After the casting was completed, the prepared membrane was immersed in 100 DEG C deionized water and boiled for about 1 hour to remove the residue, thereby obtaining a PBI membrane.

Example 1. PBI / POSS -N &lt; / RTI &gt; 10 wt% &lt; RTI ID = 0.0 &

A PBI / DMAc solution (1: 19 ratio) was prepared by dissolving 0.5 g of the PBI powder obtained in Preparation Example 3 in 9.5 g of DMAc. 0.05 g of POSS-N obtained in Preparation Example 2 was dissolved in 0.95 g of DMAc to prepare a POSS-N / DMAc solution. 10 g of PBI / DMAc solution (0.5 g of PBI) and 1 g of POSS-N / DMAc solution (POSS-N content of 0.05 g) were mixed and stirred at room temperature for 12 hours. At this time, POSS-N in PBI was induced to disperse well by ultrasonic dispersion during stirring. The dispersed solution was transferred into a glass chalet, placed in an oven at 80 DEG C, and then slowly heated to 190 DEG C for 24 hours. The nanocomposite membrane thus formed was immersed in deionized water and boiled for 1 hour to remove the residues, thereby obtaining a PBI / POSS-N nanocomposite membrane containing 10% by weight of POSS-N based on PBI.

The obtained PBI / POSS-N nanocomposite membrane was immersed in a phosphoric acid solution maintained at 60 ° C., and the weight was measured at intervals of 1 hour. The PBI / POSS-N nanocomposite membrane thus immersed was taken out of the phosphoric acid solution when no further weight change was observed over time. At this time, the difference in weight with the membrane before immersion in phosphoric acid is the maximum amount of phosphoric acid-doped. The phosphoric acid doping was fixed at 80 wt% with respect to the polymer. The weight of the PBI / POSS-N nanocomposite membrane measured according to immersion time is shown in FIG.

Example 2. PBI / POSS -N &lt; / RTI &gt; 20 wt% nanocomposite membrane preparation and phosphoric acid doping

The PBI / POSS-N nanosubstance containing 20% by weight of POSS-N based on PBI was obtained by performing the same method as that of the nanocomposite membrane of Example 1 using 0.1 g of POSS-N obtained in Preparation Example 2 And the obtained PBI / POSS-N nanocomposite membrane was doped with phosphoric acid by the same method as that of the phosphoric acid doping method of Example 1 above. At this time, the weight of the PBI / POSS-N nanocomposite membrane measured according to immersion time is shown in FIG.

Comparative Example. PBI  Phosphate doping of membrane

The PBI film obtained in Production Example 4 was doped with phosphoric acid in the same manner as in the phosphoric acid doping method of Example 1 above. At this time, the weight of the PBI membrane measured according to immersion time is shown in FIG.

In this regard, FIG. 1 is a graph showing a change in the amount of phosphoric acid doping over time of the phosphoric acid doping of the PBI film of the comparative example and the nanocomposite film of this embodiment. As shown in Fig. 1, it was found that the amount of phosphoric acid doped increased with time, and the weight change no longer changed after about 5 hours. In addition, the amount of phosphoric acid doped increases as the amine group content of the POSS-N according to the present embodiment increases, and the phosphoric acid doping amount of the PBI film of the comparative example is at most 81% by weight, It was confirmed that the amount of phosphoric acid escape of the 20 wt% nanocomposite membrane of POSS-N increased up to 88 wt%. It was confirmed that the phosphoric acid doped with amine group of POSS-N was further caught through hydrogen bonding to further increase doping amount of phosphoric acid.

Experimental Example 1 PBI  Membrane and PBI / POSS -N Proton Conductivity Measurement of Nanocomposite Membrane

The proton conductivities of the composite membranes and the electrolyte membranes prepared in Examples 1 and 2 and Comparative Examples were measured using a constant current four-terminal method. A method of measuring the difference between the AC potentials generated at the center of the specimens while applying a constant alternating current to the specimens of 0.5 cm x 2 cm in size in a room with controlled temperature and humidity, The proton conductivity was measured under no humidification condition at 120 ℃. Proton conductivity measurements were performed using SI 1287 from Solatron.

In this connection, FIG. 2 is a graph showing the proton conductivity of the PBI film of the comparative example and the nanocomposite film according to this embodiment. As shown in FIG. 2, the PBI film of the comparative example exhibited a proton conductivity of about 0.045 S / cm. In contrast, in the above embodiments, the content of POSS-N increases from 10 wt% to 20 wt% , And a maximum proton conductivity of 0.055 S / cm. It was confirmed that the amine group of POSS-N helped proton transfer of doped phosphoric acid.

Experimental Example 2 PBI  Membrane and PBI / POSS -N Nano Composite Membrane Mechanical Strength and Tensile Ratio Measure

The composite membranes and electrolyte membranes prepared in Examples 1 and 2 and Comparative Examples were measured for mechanical strength and tensile modulus using an Instron 4201 / ASTM D882 method. The specimen was prepared to have a size of 0.5 cm x 5 cm and the degree of elongation and the mechanical strength of the specimen were measured at a rate of 5 mm / min.

In this regard, FIG. 3 is a graph showing the mechanical strength and tensile ratio of the PBI film of the comparative example and the nanocomposite film according to this embodiment. As shown in FIG. 3, the PBI / POSS-N nanocomposite membrane according to the present embodiments exhibits an increased strength of 80% or more, while a mechanical strength of the comparative PBI membrane is about 4.2 MPa. MPa. &Lt; / RTI &gt; In addition, the tensile rate (%) of the PBI film of the comparative example was about 20%, whereas the addition of POSS-N according to the present example showed a maximum increase of 30%. This is because POSS-N increases the mechanical strength and tensile ratio by forming a molecular-level nanocomposite.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention .

Claims (19)

Benzimidazole polymers; And
A polyhedral oligomeric silsesquioxane represented by the following general formula (1)
/ RTI &gt;
Polybenzimidazole Nanocomposite Membrane Using Amine Group-Containing Silsesquioxane:
[Chemical Formula 1]

;
In Formula 1,
R is an amine group-containing substituent.
The method according to claim 1,
The amine group-containing substituent is selected from the group consisting of -NH ₂ , -O-NH ₂ , -R-NH ₂ , - (CH ₂ ) _n -NH ₂ (n is an integer of 1 to 20)

,

, And isomers thereof. The polybenzimidazole nanocomposite membrane employs an amine group-containing silsesquioxane.
The method according to claim 1,
Wherein the benzimidazole-based polymer comprises polybenzimidazole, and derivatives thereof. The polybenzimidazole nanocomposite membrane according to claim 1, wherein the benzimidazole-based polymer is selected from the group consisting of polybenzimidazole and derivatives thereof.
The method of claim 3,
The benzimidazole-based polymer may be prepared,

,

,

,

, And isomers thereof, and wherein n is an integer of 1 to 20. The polybenzimidazole nanocomposite membrane using the amine group-containing silsesquioxane.
The method according to claim 1,
Wherein the benzimidazole-based polymer has a molecular weight of from 5,000 to 1,000,000. The polybenzimidazole nanocomposite membrane according to claim 1, wherein the benzimidazole-based polymer comprises an amine group-containing silsesquioxane.
The method according to claim 1,
Wherein the polyhedral oligomeric silsesquioxane has a size on the order of nanometers. 2. The polybenzimidazole nanocomposite membrane according to claim 1, wherein the polyhedral oligomeric silsesquioxane has a size on the order of nanometers.
The method according to claim 1,
Wherein the polyhedral oligomeric silsesquioxane comprises 1 to 16 amine groups. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt;
8. The method of claim 7,
Wherein the polyhedral oligomeric silsesquioxane comprises 3 to 16 amine groups. The polybenzimidazole nanocomposite membrane according to claim 1, wherein the polyhedral oligomeric silsesquioxane comprises 3 to 16 amine groups.
The method according to claim 1,
Wherein the polyhedral oligomeric silsesquioxane substituted by the amine group is contained in an amount of 1 to 50% by weight based on the benzimidazole-based polymer, wherein the polybenzimidazole nano-type silsesquioxane Composite membrane.
The method of claim 9, wherein
Wherein the amine group-containing polyhedral oligomeric silsesquioxane is contained in an amount of 1 to 30% by weight based on the benzimidazole-based polymer, wherein the amine group-containing silsesquioxane comprises polybenzimidazole nano Composite membrane.
The method according to claim 1,
And the mechanical strength is maintained even if the thickness of the nanocomposite membrane is reduced. The polybenzimidazole nanocomposite membrane using the amine group-containing silsesquioxane.
Containing silsesquioxane-based polymer, a polyhedral oligomeric silsesquioxane substituted with an amine group-containing substituent, and a benzimidazole-based polymer to prepare a benzimidazole-based polymer / silsesquioxane nanocomposite film, A process for preparing a polybenzimidazole nanocomposite membrane using sesquioxane.
13. The method of claim 12,
Wherein the polyhedral oligomeric silsesquioxane comprises 1 to 16 amine groups, wherein the polyhedral oligomeric silsesquioxane comprises 1 to 16 amine groups.
14. The method of claim 13,
Wherein the polyhedral oligomeric silsesquioxane comprises 3 to 16 amine groups. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt;
13. The method of claim 12,
Wherein the polyhedral oligomeric silsesquioxane substituted by the amine group-containing substituent is added in an amount of 1 wt% to 50 wt% based on the benzimidazole-based polymer. A method for preparing a ribbimidazole nanocomposite membrane.
16. The method of claim 15,
Wherein the polyhedral oligomeric silsesquioxane substituted with the amine group-containing substituent is added in an amount of 10 to 20 wt% based on the benzimidazole-based polymer. A method for preparing a ribbimidazole nanocomposite membrane.
13. The method of claim 12,
A method for producing a polybenzimidazole nanocomposite membrane using amine group-containing silsesquioxane, further comprising doping the benzimidazole-based polymer / silsesquioxane nanocomposite membrane with phosphoric acid.
18. The method of claim 17,
The doping with the phosphoric acid is carried out by immersing the benzimidazole-based polymer / silsesquioxane nanocomposite membrane in a phosphoric acid solution. The polybenzimidazole nano-particles using the amine group-containing silsesquioxane A method for producing a composite membrane.
A fuel cell comprising a polybenzimidazole nanocomposite membrane using an amine group-containing silsesquioxane according to any one of claims 1 to 11.

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