JP4995568B2 - POLYMER ELECTROLYTE MEMBRANE, POLYMER FILM AS ITS MATERIAL, METHOD FOR PRODUCING ELECTROLYTE MEMBRANE, AND SOLID POLYMER FUEL CELL USING ELECTROLYTE MEMBRANE - Google Patents

Abstract

Disclosed is a polymer electrolyte membrane useful as a constituent of a solid polymer fuel cell, a direct liquid fuel cell or a direct methanol fuel cell. Also disclosed are a polymer film as the material for such a polymer electrolyte membrane, a method for producing an electrolyte membrane, and a solid polymer fuel cell using an electrolyte membrane. Further disclosed are a polymer electrolyte membrane having excellent proton conductivity and high methanol barrier properties which is useful as a constituent of a solid polymer fuel cell, a direct liquid fuel cell or a direct methanol fuel cell and a method for producing such a polymer electrolyte membrane. Still further disclosed are a polymer film as the material for such a polymer electrolyte membrane, and a method for producing such a polymer film. Specifically disclosed is "a polymer film essentially containing a polymer compound (A) having an aromatic unit and a polymer compound (B) having no aromatic unit". Also specifically disclosed is "a polymer film further containing a thermoplastic elastomer (C) as another essential component".

Description

  The present invention relates to a polymer electrolyte membrane, a polymer film as a material thereof, a method for producing the electrolyte membrane, and a solid polymer fuel cell using the electrolyte membrane.

  Polymer compounds containing proton-conducting groups such as sulfonic acid groups are used in electrochemical technologies such as solid polymer fuel cells, direct liquid fuel cells, direct methanol fuel cells, humidity sensors, gas sensors, and electrochromic display devices. Used as an element material. Among these, the polymer electrolyte fuel cell is expected as one of the pillars of new energy technology.

  A polymer electrolyte fuel cell using a polymer electrolyte membrane made of a polymer compound containing a proton-conducting group has features such as operation at a low temperature and reduction in size and weight. Application to consumer cogeneration systems and consumer small portable devices is under consideration. Direct liquid fuel cells, especially direct methanol fuel cells that use methanol directly as fuel, have features such as simple structure, ease of fuel supply and maintenance, and high energy density. As an alternative to ion secondary batteries, it is expected to be applied to consumer portable devices such as mobile phones and notebook computers.

  Polymer compounds containing proton-conducting substituents such as sulfonic acid groups can be used for solid polymer fuel cells, direct liquid fuel cells, direct methanol fuel cells, humidity sensors, gas sensors, electrochromic display devices, etc. Used as a raw material for chemical elements. Among these, the polymer electrolyte fuel cell is expected as one of the pillars of new energy technology.

  A polymer electrolyte fuel cell that uses an electrolyte membrane made of a polymer compound having a proton-conducting substituent can be operated at low temperatures and can be reduced in size and weight. , And application to small portable devices for consumer use. Direct liquid fuel cells, especially direct methanol fuel cells that use methanol directly as fuel, have features such as simple structure, ease of fuel supply and maintenance, and high energy density. As an alternative to batteries, it is expected to be applied to consumer portable devices such as mobile phones and laptop computers.

  As a polymer electrolyte membrane used for a polymer electrolyte fuel cell, a perfluorocarbon sulfonic acid membrane represented by Nafion (registered trademark) has been widely studied. The perfluorocarbon sulfonic acid membrane has high proton conductivity and excellent chemical stability such as acid resistance and oxidation resistance. However, Nafion (registered trademark) has a drawback that it is very expensive because of the high raw materials used and the complicated manufacturing process. Furthermore, the permeation (also referred to as crossover) of a hydrogen-containing liquid such as methanol which is a raw material of a direct liquid fuel cell is large, and a so-called chemical short reaction occurs. As a result, cathode potential, fuel efficiency, cell characteristics and the like are lowered, and it is difficult to use as a polymer electrolyte membrane of a direct liquid fuel cell such as a direct methanol fuel cell. In Nafion (registered trademark), there is a concern that fuel may be lost due to crossover even when power is not generated.

  As a proton conductive electrolyte membrane used for a polymer electrolyte fuel cell, a perfluorocarbon sulfonic acid membrane represented by Nafion (registered trademark) has been widely studied. The perfluorocarbon sulfonic acid membrane has high proton conductivity and excellent chemical stability such as acid resistance and oxidation resistance. However, Nafion (registered trademark) has a drawback that it is very expensive because of the high raw materials used and the complicated manufacturing process. Further, Nafion (registered trademark) has a large permeation (also referred to as crossover) of a hydrogen-containing liquid such as methanol, and a so-called chemical short reaction occurs. As a result, the cathode potential, fuel efficiency, cell characteristics and the like are lowered, and it is difficult to directly use as an electrolyte membrane of a methanol fuel cell. In Nafion (registered trademark), there is a concern that fuel may be lost due to crossover even when power is not generated.

  From such a background, various types of polymer electrolyte membranes have been proposed.

  For example, Patent Document 1 proposes a sulfonic acid group-containing polyphenylene sulfide that is soluble in an aprotic polar solvent. It is disclosed that by introducing a sulfonic acid group under a homogeneous solution of polyphenylene sulfide in a chlorosulfonic acid solution, solubility in an aprotic polar solvent can be imparted, and the film can be easily processed. However, in the method disclosed herein, there is a possibility that solubility in methanol, which is considered as a fuel for fuel cells, may be imparted at the same time, and the range of use thereof is significantly limited. In addition, since chlorosulfonic acid is used as the solvent and sulfonating agent, it is difficult to control the amount of sulfonic acid group introduced, or the polyphenylene sulfide may be deteriorated. Further, a large amount of acid waste liquid is discharged during reaction, resin recovery, and washing. Further, there is no mention of the effect of suppressing permeation (also referred to as crossover) of a hydrogen-containing liquid such as methanol.

  Patent Document 2 discloses a method for producing a polymer electrolyte membrane (proton conductive polymer membrane) made of sulfonic acid group-containing polyphenylene sulfide. According to this method, a polymer electrolyte membrane comprising a solvent-insoluble sulfonic acid group-containing polyphenylene sulfide can be obtained. However, the effect of suppressing permeation (also referred to as crossover) of a hydrogen-containing liquid such as methanol is mentioned. Absent.

  For example, Patent Document 3 discloses a polymer electrolyte membrane obtained by a method in which a polymer porous support is filled with an electrolyte monomer to increase the molecular weight. Patent Document 4 discloses a polymer electrolyte membrane obtained by a method of introducing a sulfonic acid group into a polymer porous support having a high molecular weight by filling with a monomer. These are supposed to suppress the permeation (crossover) of them because the porous support suppresses the swelling of methanol and water used as fuel. However, since the manufacturing process is complicated, it is easily assumed that there are problems in terms of manufacturing cost and productivity. In addition, in order to develop sufficient proton conductivity, it is necessary to set the content of the proton conductive group in the electrolyte part high, and there is concern about the durability in this part and the durability of the electrolyte / support interface. There is.

For example, Patent Document 3 discloses a polymer electrolyte membrane in which a polymer porous support is filled with an electrolyte monomer to increase the molecular weight. In order to suppress swelling with respect to methanol and water used as fuel by the porous support, it is said that permeation (crossover) thereof is suppressed. However, since the manufacturing process is complicated, there is a problem in terms of manufacturing cost. In addition, in order to develop sufficient proton conductivity, it is necessary to set the content of the proton conductive substituent in the electrolyte part to be high, and durability in this part and durability of the electrolyte / support interface are required. There are concerns.
Japanese National Patent Publication No. 11-510198 International Publication No. 02/062896 Pamphlet Republished WO00 / 54531 Japanese Patent Laying-Open No. 2005-5171

  The object of the present invention has been made in view of the above problems, and has excellent proton conductivity useful as a constituent material of a polymer electrolyte fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell. The present invention also provides a polymer electrolyte membrane having a high methanol barrier property and a method for producing the same, and a polymer film as a material for the polymer electrolyte membrane and a method for producing the polymer film.

(1) The first of the present invention is
A polymer electrolyte membrane material used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell,
(A) a polymer compound having an aromatic unit,
(B) a polymer compound having no aromatic unit,
A polymer film containing, as an essential component,
It is.

(2) The second aspect of the present invention is
(C) a polymer film according to (1), which contains a thermoplastic elastomer as an essential component;
It is.

(3) The third aspect of the present invention is
The (A) is at least one selected from the group consisting of polystyrene, syndiotactic polystyrene, polyphenylene ether, modified polyphenylene ether, polysulfone, polyether sulfone, polyether ether ketone and polyphenylene sulfide, and derivatives thereof. The polymer film according to any one of (1) and (2),
It is.

(4) The fourth aspect of the present invention is
(A) is at least one selected from the group consisting of polystyrene, syndiotactic polystyrene and polyphenylene sulfide, The polymer film according to any one of (1) to (3),
It is.

(5) The fifth aspect of the present invention is
(B) is represented by the following general formula (1)

(Wherein, X ₁ ~ _4, in any of _{H, CH 3, Cl, F} , OCOCH 3, CN, COOH, COOCH 3, OC 4 H 9, is selected from the group consisting of, X ₁ ~ ₍₄₎ are independent of each other and may be the same or different), and are at least one selected from polymer compounds consisting of a high compound according to any one of (1) to (4) Molecular film,
It is.

(6) The sixth aspect of the present invention is
(B) is at least one selected from the group consisting of polyethylene, polypropylene, and polymethylpentene, and derivatives thereof, according to any one of (1) to (5), Molecular film,
It is.

(7) The seventh of the present invention is
“(C) is a copolymer of polystyrene or a polystyrene derivative and the following general formula (2) and / or general formula (3),” according to any one of (2) to (6), Polymer film.

(In the formula, R ₁ to ₁₂ are C _x H _{2x + 1} , and R ₁ to ₁₂ may be the same or different from each other, and l, m, n, and x are 0 or more. ) ",
It is.

(8) The eighth aspect of the present invention is
Said (C) is polystyrene-polyisobutylene-polystyrene triblock copolymer, polystyrene-poly (ethylene / propylene) block copolymer, polystyrene-poly (ethylene / propylene) -polystyrene triblock copolymer, polystyrene-poly ( It is at least one selected from the group consisting of ethylene / butylene) -polystyrene triblock copolymers and polystyrene-poly (ethylene-ethylene / propylene) -polystyrene triblock copolymers, and derivatives thereof. The polymer film according to any one of (2) to (7),
It is.

(9) The ninth of the present invention is
The polymer film according to any one of (1) to (8), wherein (B) is contained in an amount of 10% by weight to 95% by weight,
It is.

(10) The tenth aspect of the present invention is
The polymer film according to any one of (1) to (9), wherein the (A) is dispersed in the (B),
It is.

(11) The eleventh aspect of the present invention is
A polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell, and is present in the polymer film according to any one of (1) to (10) A polymer electrolyte membrane, wherein a proton conductive group is introduced into an aromatic unit,
It is.

(12) The twelfth aspect of the present invention is
The polymer electrolyte membrane according to (11), wherein the proton conductive group is a sulfonic acid group,
It is.

(13) The thirteenth aspect of the present invention is
The polymer electrolyte membrane according to any one of (11) and (12), wherein the ion exchange capacity of the polymer electrolyte membrane is 0.5 to 3.0 meq / g,
It is.

(14) The fourteenth aspect of the present invention is
The polymer electrolyte membrane according to any one of (11) to (13), wherein the proton conductivity of the polymer electrolyte membrane at 23 ° C. is 1.0 × 10 ⁻³ S / cm or more. ,
It is.

(15) The fifteenth aspect of the present invention is
Any one of (11) to (14), wherein the polymer electrolyte membrane has a methanol permeability coefficient of 2,000 μmol / (cm · day) or less with respect to a 64 wt% methanol aqueous solution at 25 ° C. Polymer electrolyte membrane,
It is.

(16) The sixteenth aspect of the present invention is
A method for producing a material for a polymer electrolyte membrane used in a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell, wherein the high level according to any one of (1) to (10) above A method for producing a polymer film, characterized by producing a molecular film by melt extrusion molding,
It is.

(17) The seventeenth aspect of the present invention is
A method for producing a polymer electrolyte membrane for use in a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell, wherein the polymer film according to any one of (1) to (10) above A method for producing a polymer electrolyte membrane, wherein the polymer electrolyte membrane is contacted with a sulfonating agent in the presence of an organic solvent,
It is.

(18) The eighteenth aspect of the present invention is
The method for producing a polymer electrolyte membrane according to (17), wherein the sulfonating agent is chlorosulfonic acid,
It is.

(19) The nineteenth aspect of the present invention is
The method for producing a polymer electrolyte membrane according to any one of (17) and (18), wherein the organic solvent is a halogenated hydrocarbon,
It is.

(20) According to the twentieth aspect of the present invention,
The halogenated hydrocarbon is at least one selected from the group consisting of dichloromethane, 1,2-dichloroethane, and 1-chlorobutane, and the high degree according to any one of (17) to (19) Manufacturing method of molecular electrolyte membrane,
It is.

(21) According to the twenty-first aspect of the present invention,
The polymer electrolyte membrane according to any one of (11) to (15) or the polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of (17) to (20) is used. A polymer electrolyte fuel cell, characterized in that
It is.

(22) The twenty-second aspect of the present invention provides
The polymer electrolyte membrane according to any one of (11) to (15) or the polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of (17) to (20) is used. A direct liquid fuel cell, characterized in that
It is.

(23) The twenty-third aspect of the present invention provides
The polymer electrolyte membrane according to any one of (11) to (15) or the polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of (17) to (20) is used. A direct methanol fuel cell, characterized in that
It is.

  Specifically, the present invention (above (1) to (23)) also discloses the following invention. In addition, (1)-(23) of this invention is the following (A-1)-(A-15), (B-1)-(B-13), (C-1)-(C-14). Is included.

  Conceptually wide are (C-1) to (C-14), and (A-1) to (A-15) and (B-1) to (B-13) are one mode. .

(A-1). No. A-1 of the present invention is
A polymer electrolyte membrane material used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell,
(A) a polymer compound having an aromatic unit,
(B) a thermoplastic elastomer,
(C) a polymer compound having no aromatic unit,
A polymer film containing, as an essential component,
It is. By using this film as a material, a polymer electrolyte membrane having excellent proton conductivity and high methanol barrier properties as described later can be realized.

(A-2). No. A-2 of the present invention is
The (A) is at least one selected from the group consisting of polystyrene, syndiotactic polystyrene, polyphenylene ether, modified polyphenylene ether, polysulfone, polyether sulfone, polyether ether ketone and polyphenylene sulfide, and derivatives thereof. A polymer film according to item (A-1) of the present invention,
It is. By using this film as a material, a preferable polymer electrolyte membrane can be realized in terms of high chemical and thermal stability and easy introduction of proton conductive groups.

(A-3). (A-3) of the present invention is
Said (B) is a copolymer of polystyrene or a polystyrene derivative and the following general formula (2) and / or (3): (A-1) to (A-2) of the present invention A polymer film according to any one of

(In the formula, R ₁ to ₁₂ are C _x H _{2x + 1} , and R ₁ to ₁₂ may be the same or different from each other. L, m, n, and x are integers of 0 or more. .)
It is. By using this film as a material, a preferable polymer electrolyte membrane can be realized in terms of excellent processability and easy introduction of proton conductive groups.

(A-4). (A-4) of the present invention is
Said (B) is polystyrene-polyisobutylene-polystyrene triblock copolymer, polystyrene-poly (ethylene / propylene) block copolymer, polystyrene-poly (ethylene / propylene) -polystyrene triblock copolymer, polystyrene-poly ( It is at least one selected from the group consisting of ethylene / butylene) -polystyrene triblock copolymers and polystyrene-poly (ethylene-ethylene / propylene) -polystyrene triblock copolymers, and derivatives thereof. The polymer film according to any one of (A-1) to (A-3) of the present invention,
It is. By using this film as a material, compatibility and dispersibility of each component are improved, workability and mechanical properties are excellent, and a proton-conducting group can be easily introduced. it can.

(A-5). (A-5) of the present invention is
Said (C) is at least 1 sort (s) selected from the high molecular compound which consists of following General formula (1), Any one of (A-1)-(A-4) of this invention characterized by the above-mentioned. The polymer film described,

(Wherein, X ₁ ~ _4, in any of _{H, CH 3, Cl, F} , OCOCH 3, CN, COOH, COOCH 3, OC 4 H 9, is selected from the group consisting of, X ₁ ~ ₄ may be the same or different from each other)
It is. By using this film as a material, a polymer electrolyte membrane having high chemical stability and excellent methanol barrier properties as described later can be realized.

(A-6). (A-6) of the present invention is
The polymer film according to any one of (A-1) to (A-5) of the present invention, wherein (C) is polyethylene and / or polypropylene.
It is. By using this film as a material, a polymer electrolyte membrane having high chemical stability and excellent methanol barrier properties as described later can be realized.

(A-7). (A-7) of the present invention is
The polymer film according to any one of (A-1) to (A-6), wherein (C) is contained in an amount of 40% by weight to 90% by weight in the polymer film. Molecular film.
It is. By using this film as a material, a polymer electrolyte membrane having high chemical stability and excellent methanol barrier properties as described later can be realized.

  The polymer film of the present invention described in the above (A-1) to (A-7) is a material for a polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell. And is preferably used.

(A-8). (A-8) of the present invention is
A polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell, wherein the polymer electrolyte membrane is any one of (A-1) to (A-7) of the present invention. A polymer electrolyte membrane, wherein a proton conductive group is introduced into an aromatic unit present in the polymer film described above,
It is.

(A-9). (A-9) of the present invention is
The polymer electrolyte membrane according to (A-8) of the present invention, wherein the proton conductive group is a sulfonic acid group,
It is.

  As shown in the above (A-1) to (A-9) of the present invention, that is, the present invention is a polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell. And a polymer film which is a material of the polymer electrolyte membrane. The polymer electrolyte membrane of the present invention comprises at least three kinds of polymer compounds of a polymer compound having an aromatic unit, a thermoplastic elastomer, and a polymer compound having no aromatic unit, and has excellent proton conductivity. And high methanol barrier properties.

  The polymer compound having an aromatic unit is selected from the group consisting of polystyrene, syndiotactic polystyrene, polyphenylene ether, modified polyphenylene ether, polysulfone, polyethersulfone, polyetheretherketone and polyphenylene sulfide, and derivatives thereof. It is preferable that at least one of them is high in chemical and thermal stability and can easily introduce a proton conductive group.

  Further, when the thermoplastic elastomer is a copolymer of polystyrene or a polystyrene derivative and the following general formula (2) and / or (3), workability and mechanical properties of the resulting polymer film and polymer electrolyte membrane are obtained. It is preferable because of excellent characteristics and easy introduction of proton conductive groups.

(In the formula, R ₁ to ₁₂ are C _x H _{2x + 1} , and R ₁ to ₁₂ may be the same or different from each other. L, m, n, and x are integers of 0 or more. .)
Furthermore, the thermoplastic elastomer is polystyrene-polyisobutylene-polystyrene triblock copolymer, polystyrene-poly (ethylene / propylene) block copolymer, polystyrene-poly (ethylene / propylene) -polystyrene triblock copolymer, polystyrene. -At least one selected from the group consisting of poly (ethylene / butylene) -polystyrene triblock copolymers and polystyrene-poly (ethylene-ethylene / propylene) -polystyrene triblock copolymers, and derivatives thereof The compatibility and dispersibility of each component are improved, the processability and mechanical properties are excellent, and the sulfonic acid group is easily introduced.

  Moreover, it is preferable that the polymer compound having no aromatic unit is at least one selected from the following general formula (1) because of high chemical stability and excellent methanol barrier properties.

(Wherein, X ₁ ~ _4, in any of _{H, CH 3, Cl, F} , OCOCH 3, CN, COOH, COOCH 3, OC 4 H 9, is selected from the group consisting of, X ₁ ~ ₄ may be the same or different from each other)
Furthermore, it is preferable that the polymer compound having no aromatic unit is polyethylene and / or polypropylene because it has high chemical stability, excellent methanol blocking properties, and can be produced at low cost.

  It is particularly preferable that the polymer compound having no aromatic unit is contained in an amount of 40% by weight or more and 90% by weight or less because both excellent proton conductivity and high methanol blocking property are compatible.

  The proton conductive group is preferably a sulfonic acid group from the viewpoint of easy introduction of the proton conductive group and proton conductivity of the obtained polymer electrolyte membrane.

(A-10). (A-10) of the present invention is
A method for producing a material for a polymer electrolyte membrane used in a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell, wherein (A-1) to (A-7) of the present invention are used. A method for producing a polymer film, wherein the polymer film is produced by melt extrusion molding,
It is.

(A-11). (A-11) of the present invention is
A method for producing a polymer electrolyte membrane for use in a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell, wherein the methods (A-1) to (A-7) of the present invention are used. Contact with a sulfonating agent in the presence of an organic solvent in any one of the polymer films, a method for producing a polymer electrolyte membrane,
It is.

(A-12). (A-12) of the present invention is
The method for producing a polymer electrolyte membrane according to (A-11) of the present invention, wherein the sulfonating agent is chlorosulfonic acid,
It is.

  As shown in the above (A-10) to (A-12) of the present invention, the present invention further relates to a polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell. And a method for producing a polymer film which is a material for the polymer electrolyte membrane. By producing the polymer film by melt extrusion, a polymer film material suitable for obtaining a polymer electrolyte membrane can be obtained with high productivity. In addition, by using a production method in which the polymer film is brought into contact with a sulfonating agent in the presence of an organic solvent, a polymer electrolyte membrane having both excellent proton conductivity and high methanol barrier properties can be obtained with ease and high productivity. It is preferable. At this time, it is preferable that the sulfonating agent is chlorosulfonic acid because a sulfonic acid group which is a proton conductive group is easily introduced, and a polymer electrolyte membrane having high proton conductivity is easily obtained.

(A-13). (A-13) of the present invention is
The polymer electrolyte membrane according to any one of the eighth and ninth aspects of the present invention,
Alternatively, a polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of (A-11) or (A-12) of the present invention,
A polymer electrolyte fuel cell, characterized in that
It is.

(A-14). (A-14) of the present invention is
The polymer electrolyte membrane according to any one of the eighth and ninth aspects of the present invention,
Alternatively, a polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of (A-11) or (A-12) of the present invention,
A direct liquid fuel cell, characterized in that
It is.

(A-15). (A-15) of the present invention is
The polymer electrolyte membrane according to any one of (A-8) and (A-9) of the present invention,
Alternatively, a polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of (A-11) or (A-12) of the present invention,
A direct methanol fuel cell, characterized in that
It is.

  As shown in the above (A-13) to (A-15) of the present invention, the solid electrolyte using the polymer electrolyte membrane of the present invention or the polymer electrolyte membrane obtained by the production method of the present invention is further used. Since the polymer fuel cell has excellent proton conductivity and high durability, it is excellent as a solid polymer fuel cell. Furthermore, the direct liquid fuel cell using the polymer electrolyte membrane of the present invention or the polymer electrolyte membrane obtained by the production method of the present invention has excellent proton conductivity and high liquid fuel barrier properties. It is excellent as a direct liquid fuel cell. Furthermore, the direct methanol fuel cell using the polymer electrolyte membrane of the present invention or the polymer electrolyte membrane obtained by the production method of the present invention has both excellent proton conductivity and high methanol barrier properties, Excellent as a methanol fuel cell.

(B-1). (B-1) of the present invention is
A material for a polymer electrolyte membrane used in a polymer electrolyte fuel cell, a direct liquid fuel cell, a direct methanol fuel cell, and at least,
(A) a polymer compound having an aromatic unit, and
(B) a polymer compound having no aromatic unit,
Including
A polymer film having a structure in which (A) is dispersed in (B),
It is. By using this film as a material, a polymer electrolyte membrane having excellent proton conductivity and high methanol barrier properties as described later can be realized.

(B-2). (B-2) of the present invention is
(A) is at least selected from the group consisting of polystyrene, syndiotactic polystyrene, polyphenylene ether, modified polyphenylene ether, polysulfone, polyethersulfone, polyetheretherketone and polyphenylene sulfide, and derivatives or copolymers thereof. The polymer film according to (B-1) of the present invention, characterized in that it is a single type,
It is. By using this film as a material, a preferable polymer electrolyte membrane can be realized in terms of high chemical and thermal stability and easy introduction of proton conductive groups.

(B-3). (B-3) of the present invention is
The polymer film according to any one of the first and second aspects of the present invention, wherein (B) is at least one selected from polymer compounds consisting of the following general formula (1):

(Wherein, X ₁ ~ _4, in any of _{H, CH 3, Cl, F} , OCOCH 3, CN, COOH, COOCH 3, OC 4 H 9, is selected from the group consisting of, X ₁ ~ ₄ may be the same or different from each other)
It is. By using this film as a material, a polymer electrolyte membrane having high chemical stability and excellent methanol barrier properties as described later can be realized.

(B-4). (B-4) of the present invention is
The polymer film according to any one of (B-1) to (B-3) of the present invention, wherein (B) is polyethylene and / or polypropylene,
It is. By using this film as a material, a polymer electrolyte membrane having high chemical stability and excellent methanol barrier properties as described later can be realized.

(B-5). (B-5) of the present invention is
The polymer film according to any one of (B-1) to (B-4) of the present invention, wherein (B) is contained in an amount of 40% by weight to 90% by weight in the polymer film. Molecular film,
It is. By using this film as a material, a polymer electrolyte membrane having high chemical stability and excellent methanol barrier properties as described later can be realized.

  The polymer film of the present invention described in the above (B-1) to (B-5) of the present invention is a polymer used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell. It is suitably used as a material for the electrolyte membrane.

(B-6). (B-6) of the present invention is
A polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell, wherein the polymer electrolyte membrane is any one of (B-1) to (B-5) of the present invention. A polymer electrolyte membrane, wherein a proton conductive group is introduced into an aromatic unit present in the polymer film described above,
It is.

(B-7). (B-7) of the present invention is
The polymer electrolyte membrane according to the sixth aspect of the present invention, wherein the proton conductive group is a sulfonic acid group,
It is.

As shown in the above (B-1) to (B-7) of the present invention, that is, the present invention is a polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell. And a polymer film which is a material of the polymer electrolyte membrane. The polymer electrolyte membrane of the present invention comprises at least two polymer compounds, a polymer compound having an aromatic unit and a polymer compound having no aromatic unit,
By adopting a structure in which a polymer compound having an aromatic unit is dispersed in a polymer compound having no aromatic unit, both excellent proton conductivity and high methanol blocking property can be achieved.

  The polymer compound having an aromatic unit is made of polystyrene, syndiotactic polystyrene, polyphenylene ether, modified polyphenylene ether, polysulfone, polyethersulfone, polyetheretherketone and polyphenylene sulfide, and derivatives and copolymers thereof. It is preferable that at least one selected from the group has high chemical and thermal stability and facilitates introduction of a proton conductive group.

  In addition, it is preferable that the polymer compound having no aromatic unit is at least one selected from polymer compounds represented by the following general formula (1) because of high chemical stability and excellent methanol blocking properties.

(Wherein, X ₁ ~ _4, in any of _{H, CH 3, Cl, F} , OCOCH 3, CN, COOH, COOCH 3, OC 4 H 9, is selected from the group consisting of, X ₁ ~ ₄ may be the same or different from each other).

  Furthermore, it is preferable that the polymer compound having no aromatic unit is polyethylene and / or polypropylene because it has high chemical stability, excellent methanol blocking properties, and can be produced at low cost.

  It is particularly preferable that the polymer compound having no aromatic unit is contained in an amount of 40% by weight or more and 90% by weight or less because both excellent proton conductivity and high methanol blocking property are compatible.

  The proton conductive group is preferably a sulfonic acid group from the viewpoint of easy introduction of the proton conductive group and proton conductivity of the obtained polymer electrolyte membrane.

(B-8). (B-8) of the present invention is
A method for producing a material for a polymer electrolyte membrane used in a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell, wherein (B-1) to (B-5) of the present invention are used. A method for producing a polymer film, wherein the polymer film is produced by melt extrusion molding,
It is.

(B-9). (B-9) of the present invention is
A method for producing a polymer electrolyte membrane for use in a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell, wherein (B-1) to (B-7) of the present invention are used. Contact with a sulfonating agent in the presence of an organic solvent in any one of the polymer films, a method for producing a polymer electrolyte membrane,
It is.

(B-10). (B-10) of the present invention is
The method for producing a polymer electrolyte membrane according to (B-9) of the present invention, wherein the sulfonating agent is chlorosulfonic acid,
It is.

  As shown in the above (B-8) to (B-10) of the present invention, the present invention further relates to a polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell. And a method for producing a polymer film which is a material for the polymer electrolyte membrane. By producing the polymer film by melt extrusion, a polymer film material suitable for obtaining a polymer electrolyte membrane can be obtained with high productivity. In addition, by using a production method in which the polymer film is brought into contact with a sulfonating agent in the presence of an organic solvent, a polymer electrolyte membrane having both excellent proton conductivity and high methanol barrier properties can be obtained with ease and high productivity. It is preferable. At this time, it is preferable that the sulfonating agent is chlorosulfonic acid because a sulfonic acid group which is a proton conductive group is easily introduced, and a polymer electrolyte membrane having high proton conductivity is easily obtained.

(B-11). (B-11) of the present invention is
The polymer electrolyte membrane according to any one of (B-6) and (B-7) of the present invention,
Alternatively, a polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of (B-9) or (B-10) of the present invention,
A polymer electrolyte fuel cell, characterized in that
It is.

(B-12). (B-12) of the present invention is
The polymer electrolyte membrane according to any one of (B-6) and (B-7) of the present invention,
Alternatively, a polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of (B-9) or (B-10) of the present invention,
A direct liquid fuel cell, characterized in that
It is.

(B-13). (B-13) of the present invention is
The polymer electrolyte membrane according to any one of (B-6) and (B-7) of the present invention,
Alternatively, a polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of (B-9) or (B-10) of the present invention,
A direct methanol fuel cell, characterized in that
It is.

  As shown in the above (B-11) to (B-13) of the present invention, a direct solid using the polymer electrolyte membrane of the present invention or the polymer electrolyte membrane obtained by the production method of the present invention. Since the polymer fuel cell has excellent proton conductivity and high durability, it is excellent as a solid polymer fuel cell. Furthermore, the direct liquid fuel cell using the polymer electrolyte membrane of the present invention or the polymer electrolyte membrane obtained by the production method of the present invention has excellent proton conductivity and high liquid fuel barrier properties. It is excellent as a direct liquid fuel cell. Furthermore, the direct methanol fuel cell using the polymer electrolyte membrane of the present invention or the polymer electrolyte membrane obtained by the production method of the present invention has both excellent proton conductivity and high methanol barrier properties, Excellent as a methanol fuel cell.

(C-1). (C-1) of the present invention is
A material for proton conductive polymer electrolyte membranes used in solid polymer fuel cells, direct liquid fuel cells, and direct methanol fuel cells, including aliphatic polymer compounds and aromatic polymer compounds A polymer film consisting of at least two polymer compounds,
It is. By using this film as a material, a polymer electrolyte membrane having excellent proton conductivity and high methanol barrier properties as described later can be realized.

(C-2). (C-2) of the present invention is
The polymer film according to claim 1, wherein the aliphatic polymer compound is contained in an amount of 10 wt% to 95 wt%.
It is. By using this film as a material, a polymer electrolyte membrane having both excellent proton conductivity and high methanol barrier properties as described later can be realized.

(C-3). (C-3) of the present invention is
The aliphatic polymer compound has the following formulas (4) to (6):

(X and Y are any of atomic groups selected from H, CH ₃ , Cl, F, OCOCH ₃ , CN, COOH, COOCH ₃ , OC ₄ H ₉ , and X and Y are the same as each other Or different.)
The polymer as described in any one of (C-1) and (C-2), which is at least one selected from aliphatic polymer compounds having a repeating unit represented by the film,
It is. By using this film as a material, a polymer electrolyte membrane having excellent chemical and thermal stability and processability can be realized.

(C-4). (C-4) of the present invention is
The aromatic polymer compound is at least one of polyphenylene sulfide, polyphenylene ether, polystyrene, syndiotactic polystyrene, polyether sulfone, and polyether ether ketone (C-1) to (C- 3) the polymer film according to any one of
It is. By using this film as a material, a preferable polymer electrolyte membrane can be realized in terms of high chemical and thermal stability and easy introduction of proton conductive groups.

  The polymer film of the present invention described above is suitably used as a material for a polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell.

(C-5). (C-5) of the present invention is
A proton conductive polymer electrolyte membrane for use in a polymer electrolyte fuel cell, a direct liquid fuel cell, or a direct methanol fuel cell, according to any one of (C-1) to (C-4) A polymer electrolyte membrane characterized in that a proton conductive group is bonded to an aromatic polymer compound present in the polymer film;
It is.

(C-6). (C-6) of the present invention is
The proton conductive polymer electrolyte membrane according to (C-5), wherein the proton conductive group is a sulfonic acid group,
It is.

  As shown in the above (C-1) to (C-6), that is, the present invention relates to a polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell. The polymer electrolyte membrane of the present invention comprises at least two polymer compounds, that is, an aliphatic polymer compound and an aromatic polymer compound containing a proton conductive group, and has excellent proton conductivity and high Has methanol barrier properties. At this time, when the aliphatic polymer compound is contained in the polymer electrolyte membrane in an amount of 10 wt% or more and 95 wt% or less, it is particularly preferable because both excellent proton conductivity and high methanol blocking properties are achieved. The aliphatic polymer compound is represented by the following formulas (4) to (6).

(X and Y are any of atomic groups selected from H, CH ₃ , Cl, F, OCOCH ₃ , CN, COOH, COOCH ₃ , OC ₄ H ₉ , and X and Y are the same as each other Or at least one selected from aliphatic polymer compounds having as a constituent a repeating unit represented by formula (1): chemical / thermal stability and processability. It is preferable because it is excellent and can be industrially obtained at low cost.

Furthermore, X in the formula (4) is H, CH ₃ , Cl, F, and X and Y in the formula (5) are (X, Y) = (CH ₃ , CH ₃ ), (X, Y) = ( Cl, Cl), (X, Y) = (F
, F), and X in Formula (6) is at least one selected from aliphatic polymer compounds having a repeating unit represented by F or H as a constituent, particularly chemically and thermally stable. This is preferable because it is excellent in workability and workability, and is industrially available at a low cost.

  Furthermore, when the aromatic polymer compound is at least one of polyphenylene sulfide, polyphenylene ether, polystyrene, syndiotactic polystyrene, polyether sulfone, polyether ether ketone, high chemical and thermal stability, Since it is easy to introduce a proton conductive group, it is preferable because the film has high proton conductivity and further high methanol blocking property.

  The proton conductive substituent is preferably a sulfonic acid group from the viewpoint of ease of introduction of the proton conductive substituent and proton conductivity of the resulting proton conductive polymer electrolyte membrane.

(C-7). (C-7) of the present invention is
The method for producing a polymer electrolyte membrane according to claim (C-6), wherein the polymer film according to any one of claims 1 to 4 is contacted with a sulfonating agent.
It is.

(C-8). (C-8) of the present invention is
The method for producing a proton conductive polymer electrolyte membrane according to claim 7, wherein the sulfonating agent is chlorosulfonic acid,
It is.

(C-9). (C-9) of the present invention is
The method for producing a polymer electrolyte membrane according to any one of (C-7) to (C-8), which is performed in an organic solvent when contacting with the sulfonating agent,
It is.

(C-10). (C-10) of the present invention is
The method for producing a polymer electrolyte membrane according to (C-9), wherein the organic solvent is a halogenated hydrocarbon compound,
It is.

(C-11). (C-11) of the present invention is
The method for producing a polymer electrolyte membrane according to (C-10), wherein the halogenated hydrocarbon compound is 1-chlorobutane,
It is.

  As shown in the above (C-7) to (C-11), the present invention further relates to a polymer film comprising at least two polymer compounds of an aliphatic polymer compound and an aromatic polymer compound. The present invention relates to a method for producing a polymer electrolyte membrane in which is contacted with a sulfonating agent. By setting it as this manufacturing method, it becomes a manufacturing method of a polymer electrolyte membrane with high productivity. Furthermore, in the method for producing a polymer electrolyte membrane of the present invention, when the aliphatic polymer compound is contained in the polymer film in an amount of 10% by weight to 95% by weight, the obtained polymer electrolyte membrane is excellent. In addition, the proton conductivity and the high methanol blocking property are compatible, which is preferable. The aliphatic polymer compound is represented by the following formulas (4) to (6).

(X and Y are any of atomic groups selected from H, CH ₃ , Cl, F, OCOCH ₃ , CN, COOH, COOCH ₃ , OC ₄ H ₉ , and X and Y are the same as each other Or different.)
When it is at least one selected from the aliphatic polymer compounds having a repeating unit represented by the formula, the chemical / thermal stability and processability are excellent, and it is industrially inexpensive. It is preferable because it is available.

Furthermore, in formula (4), X is H, CH ₃ , Cl, F, and in formula (5), X and Y are (X, Y) = (CH ₃ , CH ₃ ), (X, Y), respectively. = (Cl, Cl), (X, Y
) = (F, F), in formula (6), X is at least one selected from aliphatic polymer compounds having a repeating unit represented by F, H as a constituent component. -It is preferable because it has excellent thermal stability and processability, and is industrially available at a low cost.

Furthermore, the aromatic polymer compound is preferably an aromatic polymer compound because it can be industrially obtained at low cost. Furthermore, when the aromatic polymer compound is at least one of polyphenylene sulfide, polyphenylene ether, polystyrene, syndiotactic polystyrene, polyether sulfone, polyether ether ketone, high chemical and thermal stability, Since it is easy to introduce a proton conductive group, it is preferable because the film has high proton conductivity and further high methanol blocking property.

  In the method for producing a polymer electrolyte membrane of the present invention, when the sulfonating agent is chlorosulfonic acid, sulfonation can be performed in a short time, and the production method of the proton conductive polymer electrolyte can be reduced at a low production cost. preferable. In the method for producing a proton conductive polymer electrolyte membrane of the present invention, when the contact with the sulfonating agent is carried out in an organic solvent, the sulfonation reaction can be carried out uniformly, so that a membrane having high mechanical strength is preferred. Furthermore, it is preferable that the organic solvent is a halogenated hydrocarbon compound because it can be industrially obtained at a low cost, and it becomes a method for producing a polymer electrolyte membrane at a low production cost. Furthermore, it is preferable that the halogenated hydrocarbon-based compound is 1-chlorobutane because the obtained proton conductive polymer electrolyte membrane has both excellent proton conductivity and high methanol blocking property.

(C-12). (C-12) of the present invention is
A polymer electrolyte membrane according to any one of claims 5 to 6, or a production method according to any one of (C-7) to (C-11), wherein the proton conductivity is high. A polymer electrolyte fuel cell using a polymer electrolyte membrane,
It is.

(C-13). (C-13) of the present invention is
A polymer electrolyte membrane according to any one of claims 5 to 6, or a production method according to any one of (C-7) to (C-11), wherein the proton conductivity is high. A direct liquid fuel cell using a molecular electrolyte membrane,
It is.

(C-14). (C-14) of the present invention is
The direct liquid fuel cell according to (C-13), wherein the direct liquid fuel cell is a direct methanol fuel cell,
It is.

  As shown in the above (C-12) to (C-14), the polymer electrolyte membrane of the present invention or the polymer electrolyte fuel cell using the polymer electrolyte membrane obtained by the production method of the present invention Is excellent as a solid polymer fuel cell because it has high proton conductivity and high durability. Furthermore, since the direct liquid fuel cell using the polymer electrolyte membrane of the present invention or the polymer electrolyte membrane obtained by the production method of the present invention has high proton conductivity and high liquid fuel barrier properties, It is excellent as a direct liquid fuel cell. Furthermore, since the direct methanol fuel cell using the polymer electrolyte membrane of the present invention or the polymer electrolyte membrane obtained by the production method of the present invention has high proton conductivity and high methanol barrier property, Excellent as a fuel cell.

  According to the present invention, high proton conductivity and high methanol blocking are achieved by a polymer electrolyte membrane composed of at least two compounds of an aliphatic polymer compound and an aromatic polymer compound containing a proton conductive group. It became possible to express sex. These have excellent proton conductivity and high methanol barrier properties, and are useful as polymer electrolyte membranes for solid polymer fuel cells, direct liquid fuel cells, and direct methanol fuel cells. Moreover, it became possible to implement | achieve said polymer electrolyte membrane by using the polymer film of this invention as a material.

  According to the present invention, in a polymer film comprising at least three polymer compounds as essential components, a polymer compound having an aromatic unit, a thermoplastic elastomer, and a polymer compound having no aromatic unit. Polymer electrolyte membranes with proton conductive groups introduced into aromatic units have excellent proton conductivity and high methanol barrier properties, such as solid polymer fuel cells, direct liquid fuel cells, and direct methanol fuels It is useful as a polymer electrolyte membrane for batteries. Moreover, it became possible to implement | achieve said polymer electrolyte membrane by using the polymer film of this invention as a material.

According to the present invention, it comprises at least two polymer compounds, a polymer compound having an aromatic unit and a polymer compound having no aromatic unit,
A proton conductive group is introduced into the aromatic unit in the polymer film having a structure in which the polymer compound having the aromatic unit is dispersed in the polymer compound having no aromatic unit. The polymer electrolyte membrane has excellent proton conductivity and high methanol barrier properties, and is useful as a polymer electrolyte membrane for solid polymer fuel cells, direct liquid fuel cells, and direct methanol fuel cells. Moreover, it became possible to implement | achieve said polymer electrolyte membrane by using the polymer film of this invention as a material.

  The polymer electrolyte membrane and the polymer film as the material thereof used for the solid polymer fuel cell, direct liquid fuel cell, and direct methanol fuel cell of the present invention will be described.

  In the present invention, the derivative means that at least one of hydrogen atoms that can be substituted in the basic compound is an aliphatic hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, hydroxyl group, carbonyl group. , A compound substituted with a substituent such as a carboxyl group, an ether group, an ester group, an acyl group or an amino group.

  The copolymer may be either a block copolymer or a random copolymer.

  The polymer electrolyte of the present invention and the polymer film of the material preferably include a polymer compound having an aromatic unit. A proton conductive group such as a sulfonic acid group can be substituted for the aromatic unit contained in the polymer compound, and when the polymer electrolyte membrane is formed, the proton conductivity can be expressed. Examples of the polymer compound having an aromatic unit include polystyrene, syndiotactic polystyrene, polyaryl ether sulfone, polyether ether sulfone, polyether ketone, polyether ketone ketone, polysulfone, polyparaphenylene, polyphenylene sulfide, and polyphenylene ether. , Modified polyphenylene ether, polyphenylene sulfoxide, polyphenylene sulfide sulfone, polyphenylene sulfone, polybenzimidazole, polybenzoxazole, polybenzothiazole, polyether sulfone, poly 1,4-biphenylene ether ether sulfone, polyarylene ether sulfone, polyimide, polyether Examples include imides, cyanate ester resins, and polyether ether ketones. That. In addition, derivatives and copolymers thereof are also within the scope of the present invention. In particular, compatibility and dispersibility with other polymer compound components, ease of introduction of proton conductive groups, processability when producing polymer films, handling properties of the resulting polymer films, and further In view of proton conductivity, methanol blocking property, chemical / thermal stability, etc. of the polyelectrolyte produced, polystyrene, syndiotactic polystyrene, polyphenylene ether, modified polyphenylene ether, polysulfone, polyethersulfone, polyetheretherketone and It is preferably at least one selected from the group consisting of polyphenylene sulfide, and derivatives and copolymers thereof. Examples of the copolymer of the polymer compound include a copolymer of polystyrene or a polystyrene derivative and the following general formula (2) and / or (3).

  The polymer electrolyte of the present invention and the polymer film of the material preferably include a thermoplastic elastomer. Due to the presence of the thermoplastic elastomer, the compatibility and dispersibility with other polymer compound components and the film physical properties are improved accordingly, and the mechanical strength and handling properties of the polymer film and polymer electrolyte membrane of the present invention are improved. Etc. are improved and preferable. Moreover, if the thermoplastic elastomer component contains an aromatic unit, an improvement in proton conductivity of the polymer electrolyte membrane can be expected, and even if no aromatic unit is contained, an improvement in methanol barrier properties can be expected. The thermoplastic elastomer used in the present invention is preferably a copolymer of polystyrene or a polystyrene derivative and the following general formula (2) and / or (3).

(In the formula, R ₁ to ₁₂ are C _x H _{2x + 1} , and R ₁ to ₁₂ may be the same or different from each other. L, m, n, and x are integers of 0 or more. .)
Since these are units of polystyrene or polystyrene derivatives having an aromatic unit, they are excellent in compatibility with the polymer compound having the aromatic unit. Moreover, since it does not have an aromatic unit in other components, it is excellent also in the compatibility with the high molecular compound which does not have an aromatic unit mentioned later.

  Among these, in view of industrial availability, dispersibility with other polymer compound components, physical properties of the resulting polymer film and polymer electrolyte membrane, polystyrene-polyisobutylene-polystyrene triblock copolymer, polystyrene -Poly (ethylene / propylene) block copolymer, polystyrene-poly (ethylene / propylene) -polystyrene triblock copolymer, polystyrene-poly (ethylene / butylene) -polystyrene triblock copolymer and polystyrene-poly (ethylene- Ethylene / propylene) -polystyrene triblock copolymer and at least one selected from the group consisting of derivatives thereof are preferable. Since these components have a block unit having no aromatic unit, they are excellent in compatibility with a polymer compound having no aromatic unit, which will be described later.

  The polymer electrolyte of the present invention and the polymer film of the material thereof preferably contain a polymer compound having no aromatic unit. Since these have no aromatic unit in the structure, proton conductive groups such as a sulfonic acid group are not introduced into the aromatic unit. Therefore, the polymer electrolyte membrane obtained from these swells in water or an aqueous methanol solution even if a hydrophilic proton conductive group such as a sulfonic acid group is introduced into an aromatic unit of another polymer compound. A polymer electrolyte membrane having a difficult structure and having a high methanol barrier property can be obtained.

  Examples of the polymer compound having no aromatic unit usable in the present invention include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 4-methyl-1-pentene, Polyolefin resin such as homopolymer or copolymer of α-olefin such as 5-methyl-1-heptene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride Vinyl chloride resins such as olefin copolymers, polyamide resins such as nylon 6 and nylon 66, polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymers, tetrafluoroethylene-exafluoropropylene copolymers, tetra Fluoroethylene-ethylene copolymer, polychlorotrif Oroechiren, polyvinylidene fluoride, and fluorine-based resins such as polyvinyl fluoride can be exemplified. In particular, compatibility and dispersibility with other polymer compound components, processability when manufacturing polymer films, handling properties of the resulting polymer films, and methanol barrier properties of the polymer electrolytes obtained from them, In consideration of thermal stability and the like, a polymer compound composed of the following general formula (1) is preferable.

(Wherein, X ₁ ~ _4, in any of _{H, CH 3, Cl, F} , OCOCH 3, CN, COOH, COOCH 3, OC 4 H 9, is selected from the group consisting of, X ₁ ~ ₄ may be the same or different from each other)
Furthermore, in view of industrial availability, mechanical properties and handling properties of the obtained polymer film, proton conductivity, methanol blocking property, chemical stability of the obtained polymer electrolyte membrane, polyethylene and / or polypropylene It is preferable that

  In the polymer film of the present invention, the content of the polymer compound having no aromatic unit is preferably 40% by weight or more and 90% by weight or less. When the content is less than 40% by weight, the polymer electrolyte membrane has insufficient swelling suppression effect on water or aqueous methanol solution, and may not exhibit the desired methanol barrier property. On the other hand, if the amount is more than 90% by weight, the amount of the polymer compound having an aromatic unit capable of introducing a proton conductive group becomes too small, and it may be difficult to express desired proton conductivity.

As the proton conductive group contained in the polymer electrolyte of the present invention,
Any material that dissociates protons in a water-containing state can be used. For example, a sulfonic acid group, a phosphoric acid group, a carboxylic acid group, a phenolic hydroxyl group and the like can be exemplified, but not limited thereto. In view of easiness of introduction of proton conductive groups and proton conductivity of the resulting polymer electrolyte, sulfonic acid groups are preferred. The ion exchange capacity of the polymer electrolyte derived from the proton conductive group content is preferably 0.3 meq / g or more, more preferably 0.5 meq / g or more. If the ion exchange capacity is lower than 0.3 meq / g, the desired proton conductivity may not be exhibited, which is not preferable.

As the proton conductive substituent contained in the proton conductive polymer electrolyte of the present invention,
Any material that dissociates protons in a water-containing state can be used. For example, a sulfonic acid group, a phosphoric acid group, a carboxylic acid group, a phenolic hydroxyl group and the like can be exemplified, but not limited thereto. In particular, a sulfonic acid group is preferable in consideration of easy introduction of a proton conductive substituent and proton conductivity of a proton conductive polymer electrolyte to be obtained. The ion exchange capacity of the proton conductive polymer electrolyte derived from the content of the proton conductive substituent is preferably 0.3 meq / g or more, more preferably 0.5 meq / g or more. . If the ion exchange capacity is lower than 0.3 meq / g, the desired proton conductivity may not be exhibited, which is not preferable.

Below, the manufacturing method of the polymer film of this invention is demonstrated.
In the present invention, a known method can be used to obtain a polymer film. For example,
Examples thereof include melt extrusion molding such as inflation method and T-die method, calendar method, cast method, cutting method, emulsion method, hot press method, and the like. Furthermore, after obtaining the polymer film, a treatment such as biaxial stretching may be applied to control the molecular orientation or the like, or a heat treatment may be applied to control the crystallinity.
In the present invention, a known method can be used to obtain a polymer film. For example, a polymer film is
Those obtained by the inflation method, T-die method, calendar method, cast method, cutting method, emulsion method, hot press method, etc. can be used. In addition, a treatment such as biaxial stretching may be performed to control the molecular orientation or the like, or a heat treatment may be performed to control the crystallinity.

  Furthermore, it is also within the scope of the present invention to add a crosslinking agent or an initiator as necessary to introduce a crosslinked structure into the polymer film. Considering productivity, mechanical properties of the resulting polymer film, ease of control of film thickness, applicability to various resins, environmental load, etc. among the above methods, a method of manufacturing by melt extrusion molding Is preferred.

Specifically, a polymer compound having an aromatic unit, which is the main raw material of the polymer film,
It is possible to apply a method in which a thermoplastic elastomer and a polymer compound pellet or powder having no aromatic unit are mixed in advance at a predetermined blending ratio, put into an extruder set with a T die, and formed into a film while melt-kneaded. .

Specifically, a polymer compound having an aromatic unit, which is a main raw material of a polymer film, and a pellet or powder of a polymer compound having no aromatic unit are mixed in advance at a predetermined mixing ratio, and a T-die is set. A method of forming a film while being melted and kneaded can be applied.

At this time, if the extruder used is a twin screw extruder, a polymer film in which these components are melted and uniformly dispersed can be obtained.
Further, the film may be formed using pellets melt-kneaded with a twin-screw extruder so as to have a predetermined blending ratio in advance, or a masterbatch pellet may be used to achieve a predetermined blending ratio. Thus, the film may be formed while melt-kneading.
Moreover, when there is no problem in the dispersibility of the components to be combined, the film may be formed with a single screw extruder in which a T die is set.

  As the thickness of the polymer film of the present invention, any thickness can be selected depending on the application. In consideration of reducing the internal resistance of the polymer electrolyte membrane obtained from the polymer film of the present invention, the thinner the polymer film, the better. On the other hand, considering the methanol barrier property and handling property of the obtained polymer electrolyte membrane, it is not preferable that the polymer film is too thin. Considering these, the thickness of the polymer film is preferably 1.2 μm to 350 μm. If the thickness of the polymer film is less than 1.2 μm, it is difficult to form a film, and it is easy to wrinkle during processing when a proton conductive group is introduced or dried, and handling properties such as breakage occur. There is a risk of significant reduction. When the thickness of the polymer film exceeds 350 μm, the proton conductivity of the obtained polymer electrolyte membrane may be difficult to express.

  The polymer film of the present invention includes at least a polymer compound having an aromatic unit and a polymer compound having no aromatic unit, and the polymer compound having an aromatic unit is dispersed in the polymer compound having no aromatic unit. It is preferable that it is a structure. The polymer compound that does not have an aromatic unit that is difficult to introduce a hydrophilic proton conductive group represented by a sulfonic acid group suppresses swelling of the polymer electrolyte membrane with respect to hydrogen-containing liquids such as water and methanol, and has excellent methanol. It becomes possible to express blocking properties. In the present invention, the dispersion state is not particularly limited as long as the polymer compound having an aromatic unit is dispersed in the polymer compound having no aromatic unit. As an example of a preferable form, it is a sea-island structure (a structure in which a polymer compound having no aromatic unit is “sea” and a polymer compound having an aromatic unit is “island”), or a layered structure on the order of μm. Can be enumerated. At this time, if the polymer compound having an aromatic unit is too dispersed or compatible, the swelling inhibiting effect of the polymer compound having no aromatic unit may be reduced. On the other hand, when the dispersion state of the polymer compound having an aromatic unit is remarkably poor, there is a possibility that proton conductivity may be insufficient or methanol blocking property may be insufficient when a polymer electrolyte membrane is used.

Next, the manufacturing method of the polymer electrolyte membrane of this invention is demonstrated. In the present invention, it is preferable that the above-described polymer film is brought into contact with a sulfonating agent in the presence of an organic solvent. By bringing the polymer film and the sulfonating agent into contact with each other in the presence of an organic solvent, it is possible to introduce a desired amount of sulfonic acid groups while suppressing the sulfonating agent from directly contacting the polymer film and deteriorating. Become.
Examples of the sulfonating agent that can be used in the present invention include known sulfonating agents such as chlorosulfonic acid, fuming sulfuric acid, sulfur trioxide, sulfur trioxide-triethyl phosphate, concentrated sulfuric acid, and trimethylsilyl chlorosulfate. . In view of industrial availability, ease of introduction of sulfonic acid groups, and characteristics of the obtained polymer electrolyte membrane, chlorosulfonic acid is preferred.

  As the sulfonating agent of the present invention, it is preferable to use known sulfonating agents such as chlorosulfonic acid, fuming sulfuric acid, sulfur trioxide, sulfur trioxide-triethyl phosphate, concentrated sulfuric acid, trimethylsilyl chlorosulfate and the like. Considering the ease of industrial availability, the ease of introduction of sulfonic acid groups, and the properties of the resulting proton conductive polymer membrane, the use of these sulfonating agents is preferred. In particular, in the present invention, it is more preferable to use chlorosulfonic acid from the viewpoint of easy introduction of a sulfonic acid group, characteristics of the obtained membrane, industrial availability, and the like.

  The organic solvent that can be used in the present invention is not particularly limited as long as it does not deteriorate the polymer film or lose the sulfonation ability of the sulfonating agent. Considering the ease of introduction of sulfonic acid groups, etc., the organic solvent used in the present invention is preferably a halogenated hydrocarbon-based compound. Furthermore, the mechanical properties and handling properties of the resulting polymer electrolyte membrane, sulfone, In view of the ease of controlling the introduction of the acid group, etc., it is preferably a halogenated hydrocarbon containing 3 or more carbon atoms and at least one or more chlorine atoms in the molecular structural formula, and 1-chloropropane, It is at least one selected from the group consisting of 1-chlorobutane, 2-chlorobutane, 1,4-dichlorobutane, 1-chloro-2-methylpropane, 1-chloropentane, 1-chlorohexane, chlorocyclohexane preferable. Among the solvents, 1-chlorobutane is preferable from the viewpoints of industrial availability and characteristics of the obtained polymer electrolyte membrane.

  The organic solvent that can be used in the present invention is not particularly limited, but is preferably a halogenated hydrocarbon compound. The organic solvent is preferably an organic solvent containing 3 or more carbon atoms and at least one or more chlorine atoms in its molecular structural formula, and includes 1-chloropropane, 1-chlorobutane, 2-chlorobutane, 1, 4 -It is preferably at least one selected from the group consisting of dichlorobutane, 1-chloro-2-methylpropane, 1-chloropentane, 1-chlorohexane, and chlorocyclohexane, but is not limited thereto. Absent. Among the solvents, 1-chlorobutane is preferable from the viewpoints of industrial availability and the properties of the obtained proton conductive polymer membrane.

  As a usage-amount of a sulfonating agent, it is preferable that it is 0.1-100 times amount (weight ratio) with respect to a polymer film, and also 0.5-50 times amount (weight ratio) is preferable. If the amount of the sulfonating agent used is less than 0.1 times, the amount of sulfonic acid groups introduced will be small, and the resulting polymer electrolyte membrane may have insufficient properties such as proton conductivity. is there. On the other hand, when the amount exceeds 100 times, the polymer film is chemically deteriorated, the mechanical strength of the obtained polymer electrolyte membrane is lowered, handling becomes difficult, and the introduction amount of sulfonic acid groups is large. As a result, the practical properties of the polymer electrolyte membrane may be impaired, for example, the methanol barrier property may be reduced, or the polymer electrolyte membrane may be soluble in water or aqueous methanol.

  The amount of the sulfonating agent used is preferably 0.5 to 50 times, more preferably 0.5 to 30 times the weight of the polymer film. When the amount of the sulfonating agent used is less than 0.5 times the weight of the polymer film, the amount of sulfonic acid groups introduced is reduced and the properties of the resulting proton conducting polymer membrane are poor. There is a tendency to be sufficient. On the other hand, when the amount exceeds 50 times, the polymer film is chemically deteriorated, the mechanical strength of the resulting proton conductive polymer membrane is lowered, handling becomes difficult, and the amount of sulfonic acid group introduced However, the practical properties of the proton-conductive polymer membrane tend to be impaired, for example, the methanol barrier property is lowered due to excessive increase in the amount of hydrogen.

  The concentration of the sulfonating agent in the organic solvent may be appropriately set in consideration of the target introduction amount of sulfonic acid groups and reaction conditions (temperature / time). Specifically, it is preferably 0.05 to 20% by weight, and a more preferable range is 0.2 to 10% by weight. If it is lower than 0.05% by weight, the sulfonating agent and the aromatic unit in the polymer film are difficult to contact, and the desired amount of sulfonic acid group may not be introduced or may take too long to introduce. There is. On the other hand, if it exceeds 20% by weight, the introduction of sulfonic acid groups may be uneven, or the mechanical properties of the obtained polymer electrolyte membrane may be impaired.

  The concentration of the sulfonating agent in the solvent may be appropriately set in consideration of the target introduction amount of sulfonic acid groups and reaction conditions (temperature / time). Specifically, the content is preferably 0.1 to 10% by weight, and more preferably 0.2 to 10% by weight. If it is lower than 0.1% by weight, the sulfonating agent and the aromatic unit in the polymer compound are difficult to contact, and the desired sulfonic acid group cannot be introduced or it takes a long time to introduce. is there. On the other hand, if it exceeds 10% by weight, the introduction of sulfonic acid groups tends to be non-uniform or the mechanical properties of the resulting proton conducting polymer membrane tend to be impaired.

Moreover, there are no particular limitations on the reaction temperature and reaction time at the time of contacting, but it is set within the range of 0 to 100 ° C., more preferably 10 to 30 ° C., 0.5 hour or more, and further 2 to 100 hours. preferable. If the reaction temperature is lower than 0 ° C, measures such as cooling on the equipment are necessary, and the reaction may take more time than necessary. If the reaction temperature exceeds 100 ° C, the reaction proceeds excessively or side reactions occur. May cause deterioration of the film characteristics.
More preferably, the boiling point is lower than the boiling point of the organic solvent to be used because it is not necessary to use a pressure vessel.
In addition, when the reaction time is shorter than 0.5 hours, the contact between the sulfonating agent and the aromatic unit in the polymer film becomes insufficient, and it may be difficult to introduce a desired sulfonic acid group. When the time exceeds 100 hours, the productivity may be remarkably reduced, and there is a possibility that the property of the polymer electrolyte membrane is not greatly improved. In practice, it is set so that a polymer electrolyte membrane having desired characteristics can be efficiently produced in consideration of a reaction atmosphere such as a sulfonating agent and an organic solvent, a target production amount, and the like. That's fine.

Moreover, there are no particular limitations on the reaction temperature and reaction time at the time of contacting, but it is set within the range of 0 to 100 ° C., more preferably 10 to 30 ° C., 0.5 hour or more, and further 2 to 100 hours. preferable. If the reaction temperature is lower than 0 ° C, measures such as cooling on the equipment are required, and the reaction tends to take more time than necessary. If the reaction temperature exceeds 100 ° C, the reaction proceeds excessively or side reactions occur. Or the like, and the film characteristics tend to be deteriorated.
In addition, when the reaction time is shorter than 0.5 hours, the contact between the sulfonating agent and the aromatic unit in the polymer compound becomes insufficient, and the desired sulfonic acid group tends to be difficult to be introduced. When the time exceeds 100 hours, productivity tends to be remarkably lowered, and a great improvement in film characteristics tends not to be expected. Actually, it is set so that a proton conductive polymer membrane having desired characteristics can be efficiently produced in consideration of a reaction system such as a sulfonating agent and a solvent to be used and a target production amount. do it.

  More specific examples will be described. A polymer film composed of an aliphatic polymer compound and an aromatic polymer compound is obtained by using an extruder having a T-die set in a twin-screw kneading extruder and using polyethylene, an aromatic polymer compound as an aliphatic polymer compound. It can be obtained by melt-kneading pellets of two polymer compounds of polyphenylene sulfide as a molecular compound. When the obtained polymer film and 1-chlorobutane are used as the solvent and chlorosulfonic acid is used as the sulfonating agent, the addition amount of chlorosulfonic acid is 1 or more times the weight of the polymer film. The proton conductive polymer having a desired ion exchange capacity under the conditions that the chlorosulfonic acid concentration in the 1-chlorobutane solution is 0.1 wt% or more, the reaction temperature is 10 ° C. or more, and the reaction time is 3 hours or more Membranes can be prepared.

At this time, by preparing a chlorosulfonic acid / 1-chlorobutane solution having a predetermined amount and a predetermined concentration and immersing the polymer film in the solution, the hydrogen atoms and the —SO ₂ Cl groups in the aromatic units in the polymer film are reduced. Replaced. Furthermore, by bringing this into contact with water, —SO ₂ Cl
The group is hydrolyzed to become a sulfonic acid group (—SO ₃ H), and the remaining 1-chlorobutane and chlorosulfonic acid are removed to obtain a sulfonic acid group-containing polyphenylene sulfide.

  Moreover, a sulfonic acid group can be introduce | transduced with a film (film | membrane) shape by making a polymer film contact with a sulfonating agent within a reaction tank. Therefore, compared to the conventional method of synthesizing a sulfonated polymer in a homogeneous reaction system and then processing it into a membrane shape, steps such as recovery, purification, and drying of the reactants, dissolution of the sulfonated polymer in a solvent, It is preferable because steps such as coating on a support and solvent removal can be omitted. Furthermore, since the film is continuously supplied, the productivity is remarkably improved.

  In addition, by continuously removing and washing the sulfonating agent attached to and / or contained in the film immersed in the reaction vessel, it is possible to prevent peripheral devices from being corroded by the sulfonating agent and to handle the film. Improve. The conditions for removal / washing may be appropriately set in consideration of the type of sulfonating agent and polymer compound to be used, but the remaining sulfonating agent is inactivated by washing with water or neutralized using alkali. It may be processed.

  Furthermore, by continuously drying the obtained proton conducting polymer membrane, the proton conducting polymer membrane can be recovered in a practically usable form. The drying conditions may be appropriately set in consideration of the type of polymer film to be used and the characteristics of the proton conductive polymer membrane to be obtained. Since the sulfonic acid group has strong hydrophilicity, it may be swelled with water during the washing process. Therefore, it shrinks during drying, and there is a risk of wrinkles and swelling. Therefore, at the time of drying, it is preferable to dry by applying an appropriate tension in the surface direction of the proton conductive polymer membrane. Moreover, in order to suppress rapid drying, you may dry gradually under adjustment of humidity.

  You may implement the manufacturing method of the polymer electrolyte membrane of this invention continuously. That is, a polymer film of the present invention was produced from a polymer compound prepared at a predetermined compounding ratio by melt extrusion using a twin-screw extruder with a T-die set, and the polymer film containing a sulfonating agent and an organic solvent. You may supply to a sulfonation reaction tank and may implement a washing | cleaning process and a drying process continuously as needed. By this method, the productivity of the polymer electrolyte membrane is improved.

  The method for producing a proton conductive polymer membrane of the present invention may be carried out continuously. That is, a film made of a polymer compound to be processed is supplied to a stretching process, and further supplied to a reaction tank with a sulfonating agent. If necessary, a washing process and a drying process are continuously performed. You may implement. This method improves the productivity of the proton conductive polymer membrane.

  Further, according to the above method, a sulfonic acid group can be introduced in the form of a film (membrane) by bringing the polymer film into contact with a sulfonating agent in the presence of an organic solvent in a sulfonation reaction tank. Therefore, after synthesizing a polymer compound into which a sulfonic acid group has been introduced in a conventional homogeneous reaction system, compared to the method of processing into a membrane shape, the process of recovery, purification, drying, etc. of the reactant, the polymer to the solvent This is preferable because steps such as dissolution of the compound, coating on a support during casting and removal of the solvent can be omitted. Furthermore, since the polymer film is continuously supplied, the productivity is remarkably improved. In addition, by continuously removing and washing the sulfonating agent and the organic solvent adhering to and / or included in the polymer film immersed in the sulfonation reaction tank, it is possible to prevent peripheral devices from being corroded by the sulfonating agent. The handling property of the polymer film is improved. The removal / washing conditions may be appropriately set in consideration of the type of sulfonating agent and organic solvent to be used, and the structure of the polymer film, but the remaining sulfonating agent is inactivated or alkalinized by washing with water. You may use and neutralize. Furthermore, by continuously drying the obtained polymer electrolyte membrane, the polymer electrolyte membrane can be recovered in a practically usable form. What is necessary is just to set drying conditions suitably in consideration of the kind of polymer film to be used and the characteristic of the polymer electrolyte membrane obtained. Since the sulfonic acid group has strong hydrophilicity, it may be swelled with water during the washing process. Therefore, it shrinks during drying, and there is a risk of wrinkles and swelling. Therefore, at the time of drying, it is preferable to dry by applying an appropriate tension in the surface direction of the polymer electrolyte membrane. Moreover, in order to suppress rapid drying, you may dry gradually under adjustment of humidity.

When producing a polymer electrolyte membrane according to the production method of the present invention, depending on the type of sulfonating agent used and the reaction conditions for sulfonation, for example, when polyphenylene sulfide is used as a polymer compound having an aromatic unit, The sulfide unit (—S—) of polyphenylene sulfide is oxidized to a sulfoxide unit (—SO—) or a sulfone unit (—SO ₂ —), and the sulfoxide unit (—SO—) is converted to a sulfone unit (—SO ₂ —). Or a side reaction in which the hydrogen of the aromatic unit is substituted with a substituent such as —Cl may occur. However, as long as the properties of the obtained polymer electrolyte membrane are not significantly deteriorated, a structural unit resulting from the side reaction may be included.

Depending on the sulfonating agent used and the reaction conditions for sulfonation, for example, when polyphenylene sulfide is used as the aromatic polymer compound, the sulfide unit (—S—) in the polymer film may be converted to a sulfoxide unit (—SO—). ) Or a sulfone unit (—SO ₂ —), a sulfoxide unit (—SO—) is oxidized to a sulfone unit (—SO ₂ —), or hydrogen of a phenylene unit is substituted with —Cl or the like. Side reactions that are substituted with groups can occur. However, as long as the properties of the obtained proton conductive polymer membrane are not significantly reduced, a structural unit resulting from the side reaction may be included.

  In order to further improve the properties of the polymer electrolyte membrane produced by the above method, it is preferable to irradiate radiation such as electron beam, γ-ray, ion beam and the like. As a result, a crosslinked structure or the like can be introduced into the polymer electrolyte membrane, and the methanol barrier property may be improved.

  Next, a solid polymer fuel cell (direct liquid fuel cell, direct methanol fuel cell) using the polymer electrolyte membrane of the present invention will be described with reference to the drawings as an example.

  FIG. 1 is a cross-sectional view of an essential part of a polymer electrolyte fuel cell (direct liquid fuel cell, direct methanol fuel cell) using the polymer electrolyte membrane of the present invention.

  This is because a polymer electrolyte membrane 1, a catalyst layer 2 in contact with the polymer electrolyte membrane 1, a diffusion layer 3 in contact with the catalyst layer 2, and a separator 5 on the outside thereof are disposed, and a solid polymer fuel cell (directly A liquid fuel cell and a direct methanol fuel cell) are configured. The separator 5 is formed with a fuel gas or a liquid (methanol aqueous solution or the like) and 5 for feeding an oxidant.

  Generally, a membrane-electrode assembly (hereinafter referred to as MEA) is obtained by joining a catalyst layer 2 to a polymer electrolyte membrane 1 or joining a catalyst layer 2 and a diffusion layer 3 to a polymer electrolyte membrane 1. That is, it is used as a basic member of a polymer electrolyte fuel cell (direct liquid fuel cell, direct methanol fuel cell).

Methods for producing MEA are conventionally studied polymer electrolyte membranes made of perfluorocarbon sulfonic acid and other hydrocarbon polymer electrolyte membranes (for example, sulfonated polyetheretherketone, sulfonated polyethersulfone, sulfone). A known method performed with a sulfonated polysulfone, a sulfonated polyimide, a sulfonated polyphenylene sulfide, or the like is applicable.

  An example of a specific method for producing MEA is shown below, but the present invention is not limited to this.

  The catalyst layer 2 is formed by dispersing a metal-supported catalyst in a polymer electrolyte solution or dispersion to prepare a dispersion for forming the catalyst layer. The dispersion solution is applied onto a release film such as polytetrafluoroethylene by spraying, and the solvent in the dispersion solution is dried and removed to form a predetermined catalyst layer 2 on the release film. The catalyst layer 2 formed on the release film is disposed on both surfaces of the polymer electrolyte membrane 1, and hot-pressed under predetermined heating and pressurizing conditions to join the polymer electrolyte membrane 1 and the catalyst layer 2 and release them. The MEA in which the catalyst layers 2 are formed on both surfaces of the polymer electrolyte membrane 1 can be produced by peeling the mold film. In addition, a catalyst-supported gas diffusion electrode in which the dispersion solution is coated on the diffusion layer 3 using a coater or the like, the solvent in the dispersion solution is dried and removed, and the catalyst layer 2 is formed on the diffusion layer 3. The catalyst is formed on both sides of the polymer electrolyte membrane 1 by arranging the catalyst layer 2 side of the catalyst-carrying gas diffusion electrode on both sides of the polymer electrolyte membrane 1 and performing hot pressing under predetermined heating and pressurizing conditions. An MEA in which the layer 2 and the diffusion layer 3 are formed can be manufactured. As the catalyst-carrying gas diffusion electrode, a commercially available gas diffusion electrode (manufactured by E-TEK, USA, etc.) may be used.

  Examples of the polymer electrolyte solution include an alcohol solution of a perfluorocarbon sulfonic acid polymer compound (such as Nafion (registered trademark) solution manufactured by Aldrich) or a sulfonated aromatic polymer compound (for example, sulfonated polyether ether ketone). , Sulfonated polyethersulfone, sulfonated polysulfone, sulfonated polyimide, sulfonated polyphenylene sulfide, and the like) can be used. As the metal-supported catalyst, conductive particles having a high specific surface area can be used as a carrier, and examples thereof include carbon materials such as activated carbon, carbon black, ketjen black, vulcan, carbon nanohorn, fullerene, and carbon nanotube. Any metal catalyst may be used as long as it promotes the fuel oxidation reaction and oxygen reduction reaction, and the fuel electrode and the oxidant electrode may be the same or different. For example, noble metals such as platinum and ruthenium or alloys thereof can be exemplified, and a promoter for promoting their catalytic activity or suppressing poisoning by reaction by-products may be added. The dispersion solution for forming the catalyst layer may be appropriately diluted with water or an organic solvent in order to adjust the viscosity to be easily applied with a sprayer or with a coater. Moreover, you may mix fluorine-type compounds, such as tetrafluoroethylene, in order to provide water repellency to the catalyst layer 2 as needed. As the diffusion layer 3, a porous conductive material such as carbon cloth or carbon paper can be used. In order to promote the diffusibility of the fuel and the oxidant and the discharge of reaction by-products and unreacted substances, it is preferable to use those which are coated with tetrafluoroethylene or the like to impart water repellency. Further, an adhesive layer containing the polymer electrolyte as described above may be provided between the polymer electrolyte membrane 1 and the catalyst layer 2 as necessary. The conditions for hot pressing the polymer electrolyte membrane 1 and the catalyst layer 2 under heating and pressurizing conditions need to be appropriately set according to the type of polymer electrolyte contained in the polymer electrolyte membrane 1 and the catalyst layer 2 to be used. is there. In general, the temperature is lower than the thermal deterioration or thermal decomposition temperature of the polymer electrolyte membrane or the polymer electrolyte, and the temperature is higher than the glass transition point or softening point of the polymer electrolyte membrane 1 or the polymer electrolyte. It is preferable to carry out under the temperature conditions above the glass transition point and softening point of the membrane 1 and the polymer electrolyte. The pressurizing condition is preferably in the range of about 0.1 MPa to 20 MPa because the polymer electrolyte membrane 1 and the catalyst layer 2 are in sufficient contact with each other and there is no deterioration in characteristics due to significant deformation of the materials used. In particular, when the MEA is formed only from the polymer electrolyte membrane 1 and the catalyst layer 2, the diffusion layer 3 may be disposed outside the catalyst layer 2 and used only by contacting without being joined.

  The polymer electrolyte membrane of the present invention is inserted by inserting the MEA obtained by the above method between a pair of separators 4 in which a flow path 5 for feeding fuel gas or liquid and an oxidant is formed. A solid polymer fuel cell (direct liquid fuel cell, direct methanol fuel cell) is obtained. In addition, a gas containing hydrogen as a main component, a gas or liquid containing methanol as a main component as a fuel gas or liquid, and a gas containing oxygen (oxygen or air) as an oxidant are respectively supplied from separate flow paths 5. By supplying the catalyst layer 2 via the diffusion layer 3, the polymer electrolyte fuel cell generates power. At this time, when a hydrogen-containing liquid is used as a fuel, a direct liquid fuel cell is obtained, and when methanol is used, a direct methanol fuel cell is obtained.

  As the separator 4, a conductive material such as carbonite graphite or stainless steel can be used. In particular, when a metal material such as stainless steel is used, it is preferable to perform a corrosion resistance treatment.

  The polymer electrolyte fuel cell of the present invention can be used alone or in a stack to form a stack, or a fuel cell system incorporating them can be used.

  FIG. 13 is a cross-sectional view of the main part of a polymer electrolyte fuel cell (direct liquid fuel cell, direct methanol fuel cell) using the proton conductive polymer membrane of the present invention.

  Next, a solid polymer fuel cell (direct liquid fuel cell, direct methanol fuel cell) using the proton conductive polymer membrane of the present invention will be described with reference to the drawings as an example.

  This comprises a proton conducting polymer membrane 21, a catalyst-carrying gas diffusion electrode 22 in contact with the membrane 21, a fuel gas or liquid formed on the separator 24, and a flow path 3 for feeding an oxidant. Is.

The method of joining the catalyst-carrying gas diffusion electrode 22 to the proton conductive polymer membrane 21 has been studied in the past as a proton conductive polymer membrane made of a perfluorocarbon sulfonic acid membrane or a proton conductive polymer membrane made of a polymer compound. Known methods performed with molecular membranes (for example, sulfonated polyetheretherketone, sulfonated polyethersulfone, sulfonated polysulfone, sulfonated polyimide, sulfonated polyphenylene sulfide, etc.) are applicable.

  Specifically, a method using a commercially available gas diffusion electrode (manufactured by E-TEK, USA) can be exemplified, but the method is not limited thereto.

  As an actual method, an alcohol solution of a perfluorocarbon sulfonic acid polymer (such as Nafion (registered trademark) solution manufactured by Aldrich), a sulfonated polymer compound constituting the proton conductive polymer membrane of the present invention, or a known Proton conductivity of the present invention using an organic solvent solution of a sulfonated polymer compound (for example, sulfonated polyetheretherketone, sulfonated polyethersulfone, sulfonated polysulfone, sulfonated polyimide, sulfonated polyphenylene sulfide, etc.) as a binder. The surface on the catalyst layer side of the catalyst-carrying gas diffusion electrode 22 is aligned with both surfaces of the polymer film 21, and a press machine such as a hot press machine or a roll press machine is generally used. Can be joined at temperature. Moreover, it is not necessary to use a binder as needed. Further, the catalyst-carrying gas diffusion electrode 22 may be prepared using the following materials and bonded to the proton conductive polymer membrane 21 for use.

  Here, the material used to prepare the catalyst-carrying gas diffusion electrode 22 includes a metal such as platinum and ruthenium or an alloy thereof that promotes the oxidation reaction of the fuel and the reduction reaction of oxygen as a catalyst, the carrier of the catalyst, Conductive materials such as fine-particle carbon materials (for example, carbon nanohorns, fullerenes, activated carbon, carbon nanotubes, etc.) as conductive materials, fluorine-containing resins having water repellency as binders, etc., if necessary Examples of the support include carbon cloth and carbon paper, and examples of the impregnation / coating material include perfluorocarbon sulfonic acid polymers, but the present invention is not limited thereto.

  The assembly of the proton conductive polymer membrane 21 and the catalyst-carrying gas diffusion electrode 22 obtained by the above method is used as a pair of graphite in which a flow path 23 for feeding fuel gas or liquid and oxidant is formed. By inserting it between gas separators 24 such as manufactured, a polymer electrolyte fuel cell (direct liquid fuel cell, direct methanol fuel cell) comprising the proton conductive polymer membrane of the present invention can be obtained. A gas containing hydrogen as a main component or a gas or liquid containing methanol as a main component as a fuel gas or liquid, and a gas containing oxygen (oxygen or air) as an oxidant are supplied from separate flow paths 23, respectively. By supplying the catalyst-supported gas diffusion electrode 22, the polymer electrolyte fuel cell operates. At this time, when methanol is used as the fuel, a direct methanol fuel cell is obtained.

  Further, a direct methanol fuel cell using the polymer electrolyte membrane of the present invention will be described with reference to the drawings as an example.

  Further, a direct methanol fuel cell using the polymer electrolyte membrane of the present invention will be described with reference to the drawings as an example.

  FIG. 2 is a cross-sectional view of an essential part of a direct methanol fuel cell including the polymer electrolyte membrane of the present invention. The required number of MEAs 6 obtained by the above method are arranged in a plane on both sides of a fuel (methanol or methanol aqueous solution) tank 7 having a fuel (methanol or methanol aqueous solution) filling section 8 and a supply section 8. Further, a support body 9 in which an oxidant flow path 10 is formed is arranged on the outer side, and a cell and a stack of a direct methanol fuel cell are configured by being sandwiched between them.

  Furthermore, a direct methanol fuel cell using the proton conductive polymer membrane of the present invention will be described with reference to the drawings as an example.

  FIG. 14 is a cross-sectional view of the main part of a direct methanol fuel cell comprising the proton conducting polymer membrane of the present invention. The proton conducting polymer membrane 25 and the catalyst carrying electrode 26 are joined to both sides of the membrane 25 to form a membrane-electrode assembly. The required number of membrane-electrode assemblies are arranged in a plane on both sides of a fuel (methanol or aqueous methanol solution) tank 27 having a fuel (methanol or aqueous methanol solution) filling section 28 and a supply section 28. Further, a support 29 having an oxidant flow path 30 formed thereon is disposed on the outside thereof, and a cell and a stack of a direct methanol fuel cell are configured by being sandwiched between them.

  Besides the above examples, the polymer electrolyte membrane of the present invention is disclosed in JP 2001-313046, JP 2001-313047, JP 2001-93551, JP 2001-93558, JP 2001-93561, JP-A-2001-102069, JP-A-2001-102070, JP-A-2001-283888, JP-A-2000-268835, JP-A-2000-268836, JP-A-2001-2001. It can be used as an electrolyte membrane of a direct methanol fuel cell, which is publicly known in Japanese Patent No. 283892.

  In addition to the above examples, the proton conductive polymer membrane of the present invention is disclosed in JP 2001-313046 A, JP 2001-313047 A, JP 2001-93551 A, JP 2001-93558 A, JP 2001-93561 A, JP 2001-102069 A, JP 2001-102070 A, JP 2001-283888 A, JP 2000-268835 A, JP 2000-268836 A, JP It can be used as an electrolyte membrane of a direct methanol fuel cell, which is publicly known in Japanese Patent Application Publication No. 2001-283892.

  At least of an aliphatic polymer compound used in the solid polymer fuel cell, direct liquid fuel cell and direct methanol fuel cell of the present invention and an aromatic polymer compound containing a proton conductive group A polymer electrolyte membrane composed of two kinds of polymer compounds and a polymer film of the material will be described.

  The aliphatic polymer compound used in the proton conductive polymer electrolyte and the polymer film of the material according to the present invention refers to an aliphatic polymer compound having no aromatic unit in its structural unit, and the proton conductive polymer electrolyte. In the case of a membrane, it constitutes a structural unit that does not contain a proton conductive substituent. Examples of such aliphatic polymer compounds include the following formulas (4) to (6).

(X and Y are any of atomic groups selected from H, CH ₃ , Cl, F, OCOCH ₃ , CN, COOH, COOCH ₃ , OC ₄ H ₉ , and X and Y are the same as each other Or different.)
When it is at least one selected from the aliphatic polymer compounds having a repeating unit represented by the formula, the chemical / thermal stability and processability are excellent, and it is industrially inexpensive. It is preferable because it is available.

Furthermore, X in the formula (4) is H, CH ₃ , Cl, F, and X and Y in the formula (5) are (X, Y) = (CH ₃ , CH ₃ ), (X, Y) = ( Cl, Cl), (X, Y) =
(F, F), X in Formula (6) is at least one selected from aliphatic polymer compounds having a repeating unit represented by F or H as a constituent, and is chemically and thermally It is preferable because it is excellent in stability and workability and is industrially available at a low cost.

  The aromatic polymer compound referred to in the present invention is a polymer compound having an aromatic ring in the main chain or side chain, and is not particularly limited.

  Examples of the aromatic polymer compound containing a proton conductive group of the present invention include polyaryl ether sulfone, polyether ether sulfone, polyether ketone, polyether ketone ketone, polysulfone, polyparaphenylene, polyphenylene sulfide, and polyphenylene. Ether, polyphenylene sulfoxide, polyphenylene sulfide sulfone, polyphenylene sulfone, polybenzimidazole, polybenzoxazole, polybenzothiazole, polystyrene, syndiotactic polystyrene, polyethersulfone, styrene- (ethylene-butylene) styrene copolymer, styrene- ( Polyisobutylene) -styrene copolymer, poly 1,4-biphenylene ether ether sulfone, polyarylene ether sulfo , Polyimide, polyether imide, cyanate ester resins, polyether ether ketone, or the like can be exemplified. In particular, the chemical and thermal stability, the ease of introduction of proton conductive substituents, the proton conductivity of the resulting proton conductive polymer electrolyte, and the methanol blocking properties of the resulting polymer electrolyte membrane, etc. In consideration, at least one of polyphenylene sulfide, polyphenylene ether, polystyrene, syndiotactic polystyrene, polyether sulfone, and polyether ether ketone is preferable.

  In the proton conductive polymer electrolyte of the present invention, the content of the aliphatic polymer compound in the proton conductive polymer electrolyte is preferably 10% by weight or more and 95% by weight or less. If the content of the aliphatic polymer compound is smaller than the above range, the effect of containing the aliphatic polymer compound may be unclear. On the other hand, when the content of the aliphatic polymer compound is larger than the above range, proton conductivity may be difficult to express.

  Next, a proton conductive polymer electrolyte membrane in which a polymer film comprising at least two polymer compounds of the aliphatic polymer compound of the present invention and an aromatic polymer compound is brought into contact with a sulfonating agent. The manufacturing method and the manufacturing method of the polymer film which is the material are demonstrated.

  In addition, at least two kinds of polymer compounds of an aliphatic polymer compound and an aromatic polymer compound are mixed, and a known method can be applied to this. In the case of the casting method, it may be mixed in a solution. Further, it may be uniformly dispersed by melt kneading. In this case, melt kneading may be performed twice in order to improve dispersibility. In addition, it is possible to simultaneously mix and prepare a film of at least two kinds of polymer compounds of an aliphatic polymer compound and an aromatic polymer compound. For example, a method of melt-kneading and forming a film with an extruder in which a T-die is set in a twin-screw kneading extruder can be applied.

  In the present invention, the thickness of the polymer film composed of at least two kinds of polymer compounds, that is, an aliphatic polymer compound and an aromatic polymer compound, should be selected according to the intended use. Is possible. In consideration of reducing the internal resistance of the obtained polymer electrolyte membrane, the thinner the polymer film, the better. On the other hand, considering the methanol barrier property and handling property of the obtained polymer electrolyte membrane, it is not preferable that the polymer film is too thin. Considering these, the thickness of the polymer film is preferably 1.2 μm to 350 μm. If the thickness of the polymer film is less than 1.2 μm, it is difficult to produce, and tends to be wrinkled during processing, and handling properties tend to be difficult, such as breakage. If the thickness of the polymer film exceeds 350 μm, the resulting polymer electrolyte membrane may not exhibit the effect of improving the methanol barrier property.

  In order to further improve the properties of the proton conducting polymer membrane produced by the above method, it is preferable to irradiate radiation such as electron beam, γ ray, ion beam and the like.

  In summary:

  The subject is “a polymer electrolyte membrane having excellent proton conductivity and high methanol barrier properties, useful as a constituent material for solid polymer fuel cells, direct liquid fuel cells, and direct methanol fuel cells, and The manufacturing method, the polymer film which is the material of the polymer electrolyte membrane, and the manufacturing method thereof are provided. "

  In addition, the subject is “a polymer electrolyte membrane useful as a constituent material of a solid polymer fuel cell, a direct liquid fuel cell, a direct methanol fuel cell, a polymer film as a material thereof, a method for producing the electrolyte membrane, and an electrolyte A polymer electrolyte fuel cell using a membrane is provided. "

  The solution is as follows: “Aromatic compounds in a polymer film comprising at least three polymer compounds, ie, a polymer compound having an aromatic unit, a thermoplastic elastomer, and a polymer compound having no aromatic unit, as essential components. The proton conductive group is introduced into the group unit. ”

  Further, the solving means is “consisting of at least two polymer compounds, ie, a polymer compound having an aromatic unit and a polymer compound having no aromatic unit, in which the aromatic compound is not contained in the polymer compound having no aromatic unit. The proton conductive group is introduced into the aromatic unit in the polymer film having a structure in which a polymer compound having a group unit is dispersed.

  Further, the solution is “a polymer electrolyte membrane comprising at least two polymer compounds of an aliphatic polymer compound and an aromatic polymer compound containing a proton conductive group. It is a configuration in which a proton conductive group is bonded to an aromatic polymer compound present in a polymer film as a material. "

  EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited at all by these Examples, In the range which does not change the summary, it can change suitably.

Example 1
<Preparation of polymer film>
Polyphenylene sulfide (Dainippon Ink Chemical Co., Ltd., LD10p1111) is used as a polymer compound having an aromatic unit, and high-density polyethylene (HI-ZEX 3300F, manufactured by Mitsui Chemicals, Inc.) is used as a polymer compound having no aromatic unit. did.

  70 parts by weight of polyphenylene sulfide pellets and 30 parts by weight of high density polyethylene pellets were dry blended. The dry blended pellet mixture was melt-extruded by a twin screw extruder with a T die set under the conditions of a screw temperature of 290 ° C. and a T die temperature of 290 ° C. to obtain the polymer film of the present invention (polymer film) 30% by weight of high density polyethylene in it).

<Observation of dispersion state of polymer compound>
An observation sample of a polymer film was prepared by an ultrathin section method. Using a transmission electron microscope (JEM-1200EX) manufactured by JEOL, the central portion of the cross section in the thickness direction of the polymer film was observed under the condition of an acceleration voltage of 80 kV and 10,000 times. The results are shown in FIG.

<Preparation of polymer electrolyte membrane>
In a glass container, 114 g of 1-chlorobutane and 2.3 g of chlorosulfonic acid were weighed to prepare a 2% by weight chlorosulfonic acid solution. 0.27 g of the polymer film was weighed, immersed in the chlorosulfonic acid solution, and allowed to stand at 25 ° C. for 20 hours (the amount of chlorosulfonic acid added was 8.6 times the weight of the polymer film) . After standing at room temperature for 20 hours, the polymer film was recovered and washed with ion-exchanged water until neutral.

  The polymer film after washing was dried in a constant temperature and humidity chamber adjusted to 23 ° C. for 30 minutes under humidity control of relative humidity 98%, 80%, 60% and 50%, A polymer electrolyte membrane of the present invention was obtained.

<Measurement method of ion exchange capacity>
A polymer electrolyte membrane (about 10 mm × 40 mm) was immersed in 20 mL of a saturated aqueous sodium chloride solution at 25 ° C., and subjected to an ion exchange reaction in a water bath at 60 ° C. for 3 hours. After cooling to 25 ° C., the membrane was thoroughly washed with ion exchanged water, and all of the saturated aqueous sodium chloride solution and the washing water were collected. To this recovered solution, a phenolphthalein solution was added as an indicator, and neutralization titration was performed with a 0.01N sodium hydroxide aqueous solution to calculate the ion exchange capacity.

<Measurement method of proton conductivity>
A polymer electrolyte membrane (about 10 mm × 40 mm) stored in ion-exchanged water was taken out, and water on the surface of the polymer electrolyte membrane was wiped off with a filter paper. A polymer electrolyte membrane was placed in a dipolar non-sealed polytetrafluoroethylene cell, and a platinum electrode was placed on the membrane surface (on the same side) so that the distance between the electrodes was 30 mm. The membrane resistance at 23 ° C. was measured by an alternating current impedance method (frequency: 42 Hz to 5 MHz, applied voltage: 0.2 V, Hioki LCR meter 3531Z HITESTER), and proton conductivity was calculated.

<Measurement method of methanol barrier properties>
In a 25 ° C. environment, ion exchange water and a 64 wt% aqueous methanol solution were isolated with a polymer electrolyte membrane using a membrane permeation experiment apparatus (KH-5PS) manufactured by Beadrex. A solution containing methanol permeated to the ion-exchanged water side after a predetermined time (2 hours) was collected, and the amount of methanol permeated with a gas chromatograph (Gas Chromatography GC-2010 manufactured by Shimadzu Corporation) was quantified. From this quantitative result, the methanol permeation rate was determined, and the methanol permeation coefficient was calculated. The methanol permeability coefficient was calculated according to the following formula 1.

  The experimental results are shown in Table 1.

(Example 2)
<Preparation of polymer film>
A polymer film of the present invention was obtained in the same manner as in Example 1 except that 50 parts by weight of polyphenylene sulfide pellets and 50 parts by weight of high-density polyethylene pellets (50 weight parts of high-density polyethylene in the polymer film). %contains). Further, the dispersion state of the polymer compound was observed in the same manner as in Example 1. The results are shown in FIG.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. A polymer electrolyte was prepared in the same manner as in Example 1 except that 141 g of 1-chlorobutane and 4.2 g of chlorosulfonic acid were weighed to prepare a 3% by weight chlorosulfonic acid solution and the polymer film was changed to 0.33 g. A membrane was obtained (the amount of chlorosulfonic acid added was 13 times that of the polymer film). The results are shown in Table 1.

(Example 3)
<Preparation of polymer film>
A polymer film of the present invention was obtained in the same manner as in Example 1 except that 30 parts by weight of polyphenylene sulfide pellets and 70 parts by weight of high density polyethylene pellets were used (70 parts by weight of high density polyethylene in the polymer film). %contains). Further, the dispersion state of the polymer compound was observed in the same manner as in Example 1. The results are shown in FIG.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. A polymer electrolyte was prepared in the same manner as in Example 1 except that 145 g of 1-chlorobutane and 5.8 g of chlorosulfonic acid were weighed to prepare a 4 wt% chlorosulfonic acid solution and the polymer film was 0.33 g. A membrane was obtained (the amount of chlorosulfonic acid added was 17 times that of the polymer film). The results are shown in Table 1.

Example 4
<Preparation of polymer film>
A polymer film of the present invention was obtained in the same manner as in Example 3 except that polyphenylene sulfide (manufactured by Dainippon Ink & Chemicals, Inc., ML320p) was used as the polymer compound having an aromatic unit (polymer). The film contains 70% by weight of high density polyethylene). Further, the dispersion state of the polymer compound was observed in the same manner as in Example 1. The results are shown in FIG.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. A polymer electrolyte was prepared in the same manner as in Example 1 except that 119 g of 1-chlorobutane and 6.0 g of chlorosulfonic acid were weighed to prepare a 5 wt% chlorosulfonic acid solution and the polymer film was 0.28 g. A membrane was obtained (the amount of chlorosulfonic acid added was 22 times that of the polymer film). The results are shown in Table 1.

(Example 5)
<Preparation of polymer film>
A polymer film of the present invention was obtained in the same manner as in Example 3 except that polypropylene (Mitsui Chemicals, Mitsui Polypro F107DV) was used as the polymer compound having no aromatic unit (in the polymer film). 70% by weight of polypropylene). Further, the dispersion state of the polymer compound was observed in the same manner as in Example 1. The results are shown in FIG.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. A polymer electrolyte was prepared in the same manner as in Example 1 except that 136 g of 1-chlorobutane and 5.4 g of chlorosulfonic acid were weighed to prepare a 4 wt% chlorosulfonic acid solution and the polymer film was 0.31 g. A membrane was obtained (the amount of chlorosulfonic acid added was 17 times that of the polymer film). The results are shown in Table 1.

(Example 6)
<Preparation of polymer film>
A polymer film of the present invention was obtained in the same manner as in Example 5 except that polyphenylene sulfide (manufactured by Dainippon Ink & Chemicals, Inc., ML320p) was used as the polymer compound having an aromatic unit (polymer). 70% by weight of polypropylene is contained in the film). Further, the dispersion state of the polymer compound was observed in the same manner as in Example 1. The results are shown in FIG.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. A polymer electrolyte was prepared in the same manner as in Example 1 except that 119 g of 1-chlorobutane and 6.0 g of chlorosulfonic acid were weighed to prepare a 5 wt% chlorosulfonic acid solution and the polymer film was 0.28 g. A membrane was obtained (the amount of chlorosulfonic acid added was 22 times that of the polymer film). The results are shown in Table 1.

(Example 7)
<Preparation of polymer film>
Polystyrene (PS Japan Co., Ltd., PSJ polystyrene G8102) was used as the polymer compound having an aromatic unit, and high-density polyethylene (HI-ZEX 3300F, manufactured by Mitsui Chemicals, Inc.) was used as the polymer compound having no aromatic unit.

  20 parts by weight of polystyrene pellets and 80 parts by weight of high density polyethylene pellets were dry blended. The dry blended pellet mixture was melt-extruded by a twin screw extruder with a T die set under the conditions of a screw temperature of 265 ° C. and a T die temperature of 265 ° C. to obtain the polymer film of the present invention (polymer film) Contains 80% by weight of high density polyethylene). Further, the dispersion state of the polymer compound was observed in the same manner as in Example 1. The results are shown in FIG.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. A polymer electrolyte was prepared in the same manner as in Example 1 except that 128 g of 1-chlorobutane and 3.9 g of chlorosulfonic acid were weighed to prepare a 3 wt% chlorosulfonic acid solution and the polymer film was changed to 0.30 g. A membrane was obtained (the amount of chlorosulfonic acid added was 13 times that of the polymer film). The results are shown in Table 1.

(Example 8)
<Preparation of polymer film>
Polystyrene (PS Japan Co., Ltd., PSJ Polystyrene G8102) was used as a polymer compound having an aromatic unit, and polypropylene (Mitsui Chemicals Co., Ltd., Mitsui Polypro F107DV) was used as a polymer compound having no aromatic unit.

  30 parts by weight of polystyrene pellets and 70 parts by weight of polypropylene pellets were dry blended. The dry blended pellet mixture was melt-extruded by a twin screw extruder with a T die set under the conditions of a screw temperature of 265 ° C. and a T die temperature of 265 ° C. to obtain the polymer film of the present invention (polymer film) Containing 70% by weight of polypropylene). Further, the dispersion state of the polymer compound was observed in the same manner as in Example 1. The results are shown in FIG.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. A polymer electrolyte was prepared in the same manner as in Example 1 except that 91 g of 1-chlorobutane and 4.6 g of chlorosulfonic acid were weighed to prepare a 5% by weight chlorosulfonic acid solution and the polymer film was 0.21 g. A membrane was obtained (the amount of chlorosulfonic acid added was 22 times that of the polymer film). The results are shown in Table 1.

Example 9
<Preparation of polymer film>
Modified polyphenylene ether (GE Japan, EFN4230) was used as a polymer compound having an aromatic unit, and high-density polyethylene (HI-ZEX 3300F, manufactured by Mitsui Chemicals, Inc.) was used as a polymer compound having no aromatic unit.

  30 parts by weight of modified polyphenylene ether pellets and 70 parts by weight of high density polyethylene pellets were dry blended. The dry blended pellet mixture was melt-extruded by a twin screw extruder with a T die set under the conditions of a screw temperature of 265 ° C. and a T die temperature of 265 ° C. to obtain the polymer film of the present invention (polymer film) 70% by weight of high density polyethylene). Further, the dispersion state of the polymer compound was observed in the same manner as in Example 1. The results are shown in FIG.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. Except for weighing 91 g of 1-chlorobutane and 1.4 g of chlorosulfonic acid to prepare a 1.5% by weight chlorosulfonic acid solution and changing the polymer film to 0.21 g, A molecular electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 6.7 times that of the polymer film). The results are shown in Table 1.

(Example 10)
<Preparation of polymer film>
A polymer film of the present invention was obtained in the same manner as in Example 9 except that polypropylene (Mitsui Chemicals, Mitsui Polypro F107DV) was used as the polymer compound having no aromatic unit (polypropylene in the polymer film). 70% by weight). Further, the dispersion state of the polymer compound was observed in the same manner as in Example 1. The results are shown in FIG.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. A polymer electrolyte was prepared in the same manner as in Example 1 except that 98 g of 1-chlorobutane and 3.9 g of chlorosulfonic acid were weighed to prepare a 4% by weight chlorosulfonic acid solution and the polymer film was 0.23 g. A membrane was obtained (the amount of chlorosulfonic acid added was 17 times that of the polymer film). The results are shown in Table 1.

(Comparative Example 1)
<Preparation of polymer film>
As a polymer compound having an aromatic unit, polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS LD10p11) was used.

  The polyphenylene sulfide pellets were melt-extruded with a twin screw extruder in which a T die was set in a twin screw extruder under the conditions of a screw temperature of 290 ° C. and a T die temperature of 290 ° C. to obtain a polymer film.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. Except for weighing 10.9 g of 1-chlorobutane and 1.1 g of chlorosulfonic acid to prepare a 1.5 wt% chlorosulfonic acid solution and changing the polymer film to 0.16 g, the same procedure as in Example 1 was performed. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 6.9 times that of the polymer film). The results are shown in Table 1.

(Comparative Example 2)
Nafion (registered trademark) 115 manufactured by DuPont was used as the polymer electrolyte membrane. The results are shown in Table 1.

  From the observation result of the dispersion state of the polymer compounds of Examples 1 to 10 in FIGS. 3 to 12, in the polymer film of the present invention, the polymer compound having no aromatic unit (whitish portion) has an aromatic unit. It was clarified that the polymer compound (black part) showed a dispersed structure.

  From the comparison between Examples 1 to 10 and Comparative Example 2 in Table 1, the polymer electrolyte membrane obtained from the polymer film of the present invention is a polymer electrolyte membrane for a polymer electrolyte fuel cell Comparative Example 2 The proton conductivity of the same order as that of the polymer electrolyte membrane was proved to be useful as a polymer electrolyte membrane of a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell.

    From the comparison between Examples 1 to 10 and Comparative Examples 1 and 2 in Table 1, the polymer electrolyte membrane obtained from the polymer film of the present invention was compared with the conventional polymer electrolyte membrane showing equivalent proton conductivity. As a result, it was revealed that the methanol permeability coefficient was low and the methanol barrier property was high, and it was shown to be useful as a polymer electrolyte membrane for a direct liquid fuel cell such as a direct methanol fuel cell.

  From comparison between Example 1 and Tables 2 and 3 in Table 1, it becomes clear that the content of the polymer compound having no aromatic unit is higher than 40% by weight, and shows higher methanol blocking properties. The usefulness of was shown.

(Example 11)
<Preparation of polymer film>
Polystyrene (PS Japan Co., Ltd., PSJ Polystyrene G8102) as a polymer compound having an aromatic unit, and polystyrene-poly (ethylene / butylene) -polystyrene triblock copolymer (Kuraray Co., Ltd., Septon 8104) as a thermoplastic elastomer. As a polymer compound having no aromatic unit, high-density polyethylene (manufactured by Mitsui Chemicals, Inc., HI-ZEX 3300F) was used.

  20 parts by weight of polystyrene pellets, 30 parts by weight of polystyrene-poly (ethylene / butylene) -polystyrene triblock copolymer pellets, and 70 parts by weight of high-density polyethylene pellets were dry blended. The dry blended pellet mixture was melt-extruded by a twin screw extruder with a T die set under the conditions of a screw temperature of 265 ° C. and a T die temperature of 265 ° C. to obtain the polymer film of the present invention (polymer film) Containing 58% by weight of high density polyethylene).

<Preparation of polymer electrolyte membrane>
In a glass container, 101.7 g of 1-chlorobutane and 0.13 g of chlorosulfonic acid were weighed to prepare a 0.13% by weight chlorosulfonic acid solution. 0.24 g of the polymer film was weighed, immersed in the chlorosulfonic acid solution, and allowed to stand at 25 ° C. for 20 hours (the amount of chlorosulfonic acid added was 0.5 times the weight of the polymer film). . After standing at room temperature for 20 hours, the polymer film was recovered and washed with ion-exchanged water until neutral.

  The polymer film after washing was dried in a constant temperature and humidity chamber adjusted to 23 ° C. for 30 minutes under humidity control of relative humidity 98%, 80%, 60% and 50%, A polymer electrolyte membrane of the present invention was obtained.

<Measurement method of ion exchange capacity>
A polymer electrolyte membrane (about 10 mm × 40 mm) was immersed in 20 mL of a saturated aqueous sodium chloride solution at 25 ° C., and subjected to an ion exchange reaction in a water bath at 60 ° C. for 3 hours. After cooling to 25 ° C., the membrane was thoroughly washed with ion exchanged water, and all of the saturated aqueous sodium chloride solution and the washing water were collected. To this recovered solution, a phenolphthalein solution was added as an indicator, and neutralization titration was performed with a 0.01N sodium hydroxide aqueous solution to calculate the ion exchange capacity.

<Measurement method of proton conductivity>
A polymer electrolyte membrane (about 10 mm × 40 mm) stored in ion-exchanged water was taken out, and water on the surface of the polymer electrolyte membrane was wiped off with a filter paper. A polymer electrolyte membrane was placed in a dipolar non-sealed polytetrafluoroethylene cell, and a platinum electrode was placed on the membrane surface (on the same side) so that the distance between the electrodes was 30 mm. The membrane resistance at 23 ° C. was measured by an alternating current impedance method (frequency: 42 Hz to 5 MHz, applied voltage: 0.2 V, Hioki LCR meter 3531Z HITESTER), and proton conductivity was calculated.

<Measurement method of methanol barrier properties>
In a 25 ° C. environment, ion exchange water and a 64 wt% aqueous methanol solution were isolated with a polymer electrolyte membrane using a membrane permeation experiment apparatus (KH-5PS) manufactured by Beadrex. A solution containing methanol permeated to the ion-exchanged water side after a predetermined time (2 hours) was collected, and the amount of methanol permeated with a gas chromatograph (Gas Chromatography GC-2010 manufactured by Shimadzu Corporation) was quantified. From this quantitative result, the methanol permeation rate was determined, and the methanol permeation coefficient was calculated. The methanol permeability coefficient was calculated according to the following formula 1.

  The experimental results are shown in Table 2.

(Example 12)
<Preparation of polymer film>
This method was the same as in Example 11 except that 20 parts by weight of polystyrene pellets, 5 parts by weight of polystyrene-poly (ethylene / butylene) -polystyrene triblock copolymer pellets, and 80 parts by weight of high-density polyethylene pellets were used. An inventive polymer film was obtained (76% by weight of high density polyethylene was contained in the polymer film).

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. The same method as in Example 11, except that 84.7 g of 1-chlorobutane and 0.21 g of chlorosulfonic acid were weighed to prepare a 0.25 wt% chlorosulfonic acid solution and the polymer film was 0.20 g. Thus, a polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 1.1 times that of the polymer film). The results are shown in Table 2. (Example 13)
<Preparation of polymer film>
Example except that polystyrene-poly (ethylene / propylene) -polystyrene triblock copolymer (Kuraray Co., Ltd., Septon 2104) was used instead of polystyrene-poly (ethylene / butylene) -polystyrene triblock copolymer. 12 was used to obtain a polymer film of the present invention (76% by weight of high-density polyethylene was contained in the polymer film).

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. The same method as in Example 11 except that 108.6 g of 1-chlorobutane and 0.54 g of chlorosulfonic acid were weighed to prepare a 0.50 wt% chlorosulfonic acid solution and the polymer film was changed to 0.25 g. To obtain a polymer electrolyte membrane (the amount of chlorosulfonic acid added was twice that of the polymer film). The results are shown in Table 2.

(Example 14)
<Preparation of polymer film>
Polystyrene (PS Japan Co., Ltd., PSJ Polystyrene G8102) as a polymer compound having an aromatic unit, and Polystyrene-poly (ethylene / propylene) -polystyrene triblock copolymer (Kuraray Co., Ltd., Septon 2104) as a thermoplastic elastomer. Polypropylene (Mitsui Chemicals, Mitsui Polypro F107DV) was used as a polymer compound having no aromatic unit.

  30 parts by weight of polystyrene pellets, 5 parts by weight of polystyrene-poly (ethylene / propylene) -polystyrene triblock copolymer pellets, and 70 parts by weight of high-density polyethylene pellets were dry blended. The dry blended pellet mixture was melt-extruded by a twin screw extruder with a T die set under the conditions of a screw temperature of 265 ° C. and a T die temperature of 265 ° C. to obtain the polymer film of the present invention (polymer film) Containing 67% by weight of polypropylene).

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. Except that 93.0 g of 1-chlorobutane and 0.12 g of chlorosulfonic acid were weighed to prepare a 0.13% by weight chlorosulfonic acid solution and the polymer film was 0.22 g, the same as in Example 11. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 0.5 times that of the polymer film). The results are shown in Table 2.

(Example 15)
<Preparation of polymer film>
Except for 20 parts by weight of polystyrene pellets, 5 parts by weight of polystyrene-poly (ethylene / propylene) -polystyrene triblock copolymer pellets, and 80 parts by weight of polypropylene pellets, the same procedure as in Example 14 was followed. A polymer film was obtained (76% by weight of high density polyethylene was contained in the polymer film).

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. Except that 101.1 g of 1-chlorobutane and 0.51 g of chlorosulfonic acid were weighed to prepare a 0.50 wt% chlorosulfonic acid solution and the polymer film was 0.23 g, the same as in Example 11. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 2.2 times the amount of the polymer film). The results are shown in Table 2.

(Example 16)
<Preparation of polymer film>
Example except that polystyrene-poly (ethylene / butylene) -polystyrene triblock copolymer (Kuraray Co., Ltd., Septon 8104) was used instead of polystyrene-poly (ethylene / propylene) -polystyrene triblock copolymer. 15 was used to obtain a polymer film of the present invention (76% by weight of high-density polyethylene was contained in the polymer film).

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. Except that 70.1 g of 1-chlorobutane and 0.18 g of chlorosulfonic acid were weighed to prepare a 0.25 wt% chlorosulfonic acid solution and the polymer film was 0.16 g, the same as in Example 11. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 1.1 times that of the polymer film). The results are shown in Table 2.

(Comparative Example 3)
<Preparation of polymer film>
As a polymer compound having an aromatic unit, polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS LD10p1111) was used.

  The polyphenylene sulfide pellets were melt-extruded with a twin screw extruder in which a T die was set in a twin screw extruder under the conditions of a screw temperature of 290 ° C. and a T die temperature of 290 ° C. to obtain a polymer film.

<Preparation of polymer electrolyte membrane>
The polymer film obtained by the above method was used. 10.9 Chlorobutane and 1.1 g of chlorosulfonic acid were weighed to prepare a 1.5 wt% chlorosulfonic acid solution, and the polymer film was changed to 0.16 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 6.9 times that of the polymer film). The results are shown in Table 2.

(Comparative Example 4)
Nafion (registered trademark) 115 manufactured by DuPont was used as the polymer electrolyte membrane. The results are shown in Table 2.

  From the comparison between Examples 11 to 16 and Comparative Example 4 in Table 2, the polymer electrolyte membrane obtained from the polymer film of the present invention is a polymer electrolyte membrane for a polymer electrolyte fuel cell, Comparative Example 3 The proton conductivity of the same order as that of the polymer electrolyte membrane was proved to be useful as a polymer electrolyte membrane of a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell.

  From the comparison between Examples 11 to 16 and Comparative Examples 3 and 4 in Table 2, the polymer electrolyte membrane obtained from the polymer film of the present invention was compared with the conventional polymer electrolyte membrane showing equivalent proton conductivity. As a result, it was revealed that the methanol permeability coefficient was low and the methanol barrier property was high, and it was shown to be useful as a polymer electrolyte membrane for a direct liquid fuel cell such as a direct methanol fuel cell.

(Example 17)
<Preparation of polymer film composed of aliphatic polymer compound and aromatic polymer compound>
As the aliphatic polymer compound, high-density polyethylene (manufactured by Mitsui Chemicals, HI-ZEX 3300F) was used. As an aromatic polymer compound, polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS LD10p11) was used.

  70 parts by weight of the aliphatic polymer compound pellets and 30 parts by weight of the aromatic polymer compound pellets were dry blended. The dry blended pellet mixture was melt-extruded under the conditions of a screw temperature of 290 ° C. and a T-die temperature of 290 ° C. using an extruder having a T-die set in a twin-screw kneading extruder to obtain a polymer film (aliphatic High-density polyethylene, which is a polymer compound, is contained in a polymer film by 70% by weight).

<Preparation of polymer electrolyte membrane>
In a glass container, 149 g of 1-chlorobutane and 3.0 g of chlorosulfonic acid were weighed to prepare a 2.0 wt% chlorosulfonic acid solution. 0.35 g of the polymer film was weighed, immersed in a chlorosulfonic acid solution, and allowed to stand at 25 ° C. for 20 hours (the amount of chlorosulfonic acid added was 8.6 times the weight of the polymer film). After standing at room temperature for 20 hours, the polymer film was recovered and washed with ion-exchanged water until neutral.

  The polymer film after washing was dried in a constant temperature and humidity chamber adjusted to 23 ° C. for 30 minutes under humidity control of relative humidity 98%, 80%, 60% and 50%, A polymer electrolyte membrane of the present invention was obtained.

  The ion exchange capacity of this polymer electrolyte membrane was measured by the following method. A polymer electrolyte membrane of about 10 mm × 40 mm was immersed in 20 mL of a saturated aqueous sodium chloride solution at 25 ° C., and reacted in a water bath at 60 ° C. for 3 hours. After cooling to 25 ° C., the membrane was thoroughly washed with ion exchanged water, and all of the saturated aqueous sodium chloride solution and the washing water were collected. To this recovered solution, a phenolphthalein solution was added as an indicator, and neutralization titration was performed with a 0.01N sodium hydroxide aqueous solution to calculate the ion exchange capacity. The results are shown in Table 3.

Furthermore, the proton conductivity of the polymer electrolyte membrane was measured by the following method. The proton conductive polymer electrolyte membrane was cut into a circular shape with a diameter of 16 mm, and excess moisture was wiped off with a filter paper before being used for measurement. After attaching stainless steel electrodes to the front and back surfaces of the test specimen and installing them in a bipolar metal cell, the AC impedance method (frequency: 42 Hz to 5 MHz, manufactured by Hioki Denki Co., Ltd.) under the condition of a voltage of 0.5 V at room temperature. LCR meter 3531Z HITESTER
), Membrane resistance was measured, and film thickness proton conductivity was calculated. The results are shown in Table 3.

  Furthermore, the methanol barrier property of the polymer electrolyte membrane was measured by the following method. In an environment of 25 ° C., a membrane permeation experiment apparatus (KH-5PS) manufactured by Beadrex was used. Isolate ion-exchanged water and aqueous methanol solution at a predetermined concentration with a proton-conducting polymer electrolyte membrane, and collect a solution containing methanol that has permeated the ion-exchanged water after a predetermined time (2 hours). The amount of methanol permeated by chromatography GC-2010 was quantified. From this quantification result, the methanol permeation rate was determined, and the methanol permeation coefficient and methanol permeation coefficient were calculated. The methanol permeability coefficient and the methanol cutoff coefficient were calculated according to the following formulas 1 and 2. The results are shown in Table 3.

(Example 18)
A polymer film obtained in the same manner as in Example 17 was used. Proton conductivity in the same manner as in Example 17 except that 150 g of 1-chlorobutane and 4.5 g of chlorosulfonic acid were weighed to prepare a 3.0 wt% chlorosulfonic acid solution and the polymer film was changed to 0.35 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 12.9 times the weight of the polymer film). The results are shown in Table 3.

(Example 19)
A polymer film obtained in the same manner as in Example 17 was used. Proton conductivity in the same manner as in Example 17 except that 127 g of 1-chlorobutane and 4.4 g of chlorosulfonic acid were weighed to prepare a 3.5 wt% chlorosulfonic acid solution and the polymer film was 0.29 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 15.1 times the weight of the polymer film). The results are shown in Table 3.

(Example 20)
A polymer film obtained in the same manner as in Example 17 was used. Proton conductivity in the same manner as in Example 17 except that 145 g of 1-chlorobutane and 5.8 g of chlorosulfonic acid were weighed to prepare a 4.0 wt% chlorosulfonic acid solution and the polymer film was changed to 0.33 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 17.3 times the weight of the polymer film). The results are shown in Table 3.

(Example 21)
A polymer film obtained in the same manner as in Example 17 was used. Proton conductivity in the same manner as in Example 17 except that 138 g of 1-chlorobutane and 6.2 g of chlorosulfonic acid were weighed to prepare a 4.5 wt% chlorosulfonic acid solution and the polymer film was 0.32 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 19.4 times the weight of the polymer film). The results are shown in Table 3.

(Example 22)
A polymer film obtained in the same manner as in Example 17 was used. Proton conductivity in the same manner as in Example 17 except that 129 g of 1-chlorobutane and 6.5 g of chlorosulfonic acid were weighed to prepare a 5.0 wt% chlorosulfonic acid solution and the polymer film was changed to 0.30 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 21.6 times the weight of the polymer film). The results are shown in Table 3.

(Example 23)
A polymer film obtained in the same manner as in Example 17 was used. Further, dichloromethane was used in place of 1-chlorobutane. A polymer electrolyte membrane was prepared in the same manner as in Example 17 except that 798 g of dichloromethane and 8.0 g of chlorosulfonic acid were weighed to prepare a 1.0 wt% chlorosulfonic acid solution and the polymer film was changed to 1.8 g. Obtained. The results are shown in Table 3.

<Preparation of catalyst sheet>
As the cathode catalyst, 50% platinum-supported carbon (SA50BK manufactured by N.E. Chemcat) was used. A 5% Nafion (registered trademark) dispersion solution (manufactured by Aldrich) was used as a binder. A cathode catalyst and pure water were mixed at a weight ratio of 1:10 to obtain a solution A. The solution A and the binder were mixed with the cathode catalyst so that the binder had a weight ratio of 1: 7.3 to obtain a solution B. As an anode catalyst, platinum 27% ruthenium 13% supported carbon (SA27-13RCBK manufactured by NV Chemcat) was used. An anode catalyst and pure water were mixed at a ratio of 1:10 to obtain a solution C. The solution C and the binder were mixed with the anode catalyst so that the binder had a weight ratio of 1: 7.1 to obtain a solution D. The process of applying the solution B onto a 22 mm square, 50 μm thick Teflon (registered trademark) sheet washed with acetone and drying was repeated several times to obtain a platinum amount of 1 mg / cm ² to obtain a cathode catalyst sheet. Similarly, the solution D was applied to a platinum amount of 1 mg / cm ² to obtain an anode catalyst sheet.

<Preparation of membrane-electrode assembly>
The polymer electrolyte membrane described in Example 23 was used, and was sandwiched between the anode catalyst sheet and the cathode catalyst sheet, and was further sandwiched in the order of a 50 μm thick Teflon (registered trademark) sheet, filter paper, and SUS plate. This was hot pressed at 150 ° C. and 50 kgf / cm ² and held for 5 minutes. After pressing, the Teflon (registered trademark) sheet, the filter paper, and the SUS plate were removed, and the catalyst sheet, the Teflon (registered trademark) sheet, was removed to obtain a membrane-electrode assembly.

<Production of cell>
Toray's TGP-H-60 carbon paper is washed with acetone, and further, a Teflon (registered trademark) dispersion solution (POLYFLON PTFE D-1E, manufactured by Daikin Industries) is applied and baked at 360 ° C. for 1 hour for water repellent treatment. An applied diffusion layer was obtained. The center of a 180-μm-thick, 80-square Teflon (registered trademark) sheet was cut into 25 squares to form a gasket. The MEA was sandwiched between a diffusion layer and a gasket and mounted on a fuel cell cell (FC05-01SP manufactured by ElectroChem) having an electrode area of 5 cm ² . The torque pressure sandwiching the cell at this time gradually increased from 1 N · m to 2 N · m, 3 N · m, and 4 N · m.

<Evaluation of power generation characteristics of direct methanol fuel cell>
GFT-MW manufactured by Toyo Corporation was used as the evaluation device. A 1M aqueous methanol solution was supplied to the anode electrode side at a flow rate of 0.5 mL / min, and air as an oxidizing agent was supplied to the cathode electrode side at a flow rate of 160 mL / min. The power generation characteristics of the direct methanol fuel cell were evaluated at a cell temperature of 60 ° C. The results are shown in FIG.

(Example 24)
<Preparation of polymer film composed of aliphatic polymer compound and aromatic polymer compound>
As the aliphatic polymer compound, high-density polyethylene (manufactured by Mitsui Chemicals, HI-ZEX 3300F) was used. As an aromatic polymer compound, polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS LD10p11) was used.

  60 parts by weight of the aliphatic polymer compound pellets and 40 parts by weight of the aromatic polymer compound pellets were dry blended. The dry blended pellet mixture was melt-extruded under the conditions of a screw temperature of 290 ° C. and a T-die temperature of 290 ° C. using an extruder having a T-die set in a twin-screw kneading extruder to obtain a polymer film (aliphatic High-density polyethylene, which is a polymer compound, is contained in the polymer film at 60% by weight).

<Preparation of polymer electrolyte membrane>
The polymer film was used. A polymer electrolyte was prepared in the same manner as in Example 17 except that 121 g of 1-chlorobutane and 3.6 g of chlorosulfonic acid were weighed to prepare a 3.0 wt% chlorosulfonic acid solution and the polymer film was 0.28 g. A membrane was obtained (the amount of chlorosulfonic acid added was 12.9 times the weight of the polymer film). The results are shown in Table 3.

(Example 25)
A polymer film obtained in the same manner as in Example 24 was used. A polymer electrolyte membrane was prepared in the same manner as in Example 23 except that 851 g of dichloromethane and 8.5 g of chlorosulfonic acid were weighed to prepare a 1.0 wt% chlorosulfonic acid solution and the polymer film was 2.0 g. Obtained. The results are shown in Table 3.

  The power generation characteristics of a direct methanol fuel cell were evaluated in the same manner as in Example 23 except that this polymer electrolyte membrane was used. The results are shown in FIG.

(Example 26)
<Preparation of polymer film composed of aliphatic polymer compound and aromatic polymer compound>
As the aliphatic polymer compound, high-density polyethylene (manufactured by Mitsui Chemicals, HI-ZEX 3300F) was used. As an aromatic polymer compound, polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS LD10p11) was used.

  50 parts by weight of the aliphatic polymer compound pellets and 50 parts by weight of the aromatic polymer compound pellets were dry blended. The dry blended pellet mixture was melt-extruded under the conditions of a screw temperature of 290 ° C. and a T-die temperature of 290 ° C. using an extruder having a T-die set in a twin-screw kneading extruder to obtain a polymer film (aliphatic High-density polyethylene, which is a polymer compound, is contained in a polymer film at 50% by weight).

<Preparation of polymer electrolyte membrane>
The polymer film was used. A polymer electrolyte was prepared in the same manner as in Example 17 except that 136 g of 1-chlorobutane and 2.7 g of chlorosulfonic acid were weighed to prepare a 2.0 wt% chlorosulfonic acid solution and the polymer film was 0.32 g. A membrane was obtained (the amount of chlorosulfonic acid added was 8.6 times the weight of the polymer film). The results are shown in Table 3.

(Example 27)
A polymer film obtained in the same manner as in Example 26 was used. Proton conductivity in the same manner as in Example 17 except that 141 g of 1-chlorobutane and 4.2 g of chlorosulfonic acid were weighed to prepare a 3.0 wt% chlorosulfonic acid solution and the polymer film was changed to 0.33 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 12.9 times the weight of the polymer film). The results are shown in Table 3.

(Example 28)
A polymer film obtained in the same manner as in Example 26 was used. A polymer electrolyte membrane was prepared in the same manner as in Example 23 except that 875 g of dichloromethane and 4.4 g of chlorosulfonic acid were weighed to prepare a 0.5 wt% chlorosulfonic acid solution and the polymer film was 2.0 g. Obtained. The results are shown in Table 3.

  The power generation characteristics of a direct methanol fuel cell were evaluated in the same manner as in Example 23 except that this polymer electrolyte membrane was used. The results are shown in FIG.

(Example 29)
<Preparation of polymer film composed of aliphatic polymer compound and aromatic polymer compound>
As the aliphatic polymer compound, high-density polyethylene (manufactured by Mitsui Chemicals, HI-ZEX 3300F) was used. As an aromatic polymer compound, polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS LD10p11) was used.

  40 parts by weight of the aliphatic polymer compound pellets and 60 parts by weight of the aromatic polymer compound pellets were dry blended. The dry blended pellet mixture was melt-extruded under the conditions of a screw temperature of 290 ° C. and a T-die temperature of 290 ° C. using an extruder having a T-die set in a twin-screw kneading extruder to obtain a polymer film (aliphatic High-density polyethylene, which is a polymer compound, is contained in a polymer film at 40% by weight).

<Preparation of polymer electrolyte membrane>
The polymer film was used. A polymer electrolyte was prepared in the same manner as in Example 17 except that 116 g of 1-chlorobutane and 2.3 g of chlorosulfonic acid were weighed to prepare a 2.0 wt% chlorosulfonic acid solution and the polymer film was 0.27 g. A membrane was obtained (the amount of chlorosulfonic acid added was 8.6 times the weight of the polymer film). The results are shown in Table 3.

(Example 30)
A polymer film obtained in the same manner as in Example 29 was used. Proton conductivity in the same manner as in Example 17 except that 120 g of 1-chlorobutane and 3.6 g of chlorosulfonic acid were weighed to prepare a 3.0 wt% chlorosulfonic acid solution and the polymer film was 0.28 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 12.9 times the weight of the polymer film). The results are shown in Table 3.

(Example 31)
<Preparation of polymer film composed of aliphatic polymer compound and aromatic polymer compound>
As the aliphatic polymer compound, high-density polyethylene (manufactured by Mitsui Chemicals, HI-ZEX 3300F) was used. As an aromatic polymer compound, polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS LD10p11) was used.

  30 parts by weight of the aliphatic polymer compound pellets and 70 parts by weight of the aromatic polymer compound pellets were dry blended. The dry blended pellet mixture was melt-extruded under the conditions of a screw temperature of 290 ° C. and a T-die temperature of 290 ° C. using an extruder having a T-die set in a twin-screw kneading extruder to obtain a polymer film (aliphatic 30% by weight of high-density polyethylene, which is a polymer compound, is contained in the polymer film).

<Preparation of polymer electrolyte membrane>
The polymer film was used. A polymer electrolyte was prepared in the same manner as in Example 17 except that 114 g of 1-chlorobutane and 2.3 g of chlorosulfonic acid were weighed to prepare a 2.0 wt% chlorosulfonic acid solution and the polymer film was changed to 0.27 g. A membrane was obtained (the amount of chlorosulfonic acid added was 8.6 times the weight of the polymer film). The results are shown in Table 3.

(Example 32)
<Preparation of polymer film composed of aliphatic polymer compound and aromatic polymer compound>
As the aliphatic polymer compound, polypropylene (F107DV, manufactured by Mitsui Chemicals, Inc.) was used. As an aromatic polymer compound, polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS LD10p11) was used.

  70 parts by weight of the aliphatic polymer compound pellets and 30 parts by weight of the aromatic polymer compound pellets were dry blended. The dry blended pellet mixture was melt-extruded under the conditions of a screw temperature of 290 ° C. and a T-die temperature of 290 ° C. using an extruder having a T-die set in a twin-screw kneading extruder to obtain a polymer film (aliphatic (Polypropylene, a high molecular compound, is contained in the polymer film by 70% by weight).

<Preparation of polymer electrolyte membrane>
The polymer film was used. A polymer electrolyte was prepared in the same manner as in Example 17 except that 109 g of 1-chlorobutane and 4.9 g of chlorosulfonic acid were weighed to prepare a 4.5 wt% chlorosulfonic acid solution and the polymer film was changed to 0.25 g. A membrane was obtained (the amount of chlorosulfonic acid added was 19.4 times the weight of the polymer film). The results are shown in Table 3.

(Example 33)
A polymer film obtained in the same manner as in Example 32 was used. Proton conductivity in the same manner as in Example 17 except that 103 g of 1-chlorobutane and 5.2 g of chlorosulfonic acid were weighed to prepare a 5.0 wt% chlorosulfonic acid solution and the polymer film was 0.24 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 21.6 times the weight of the polymer film). The results are shown in Table 3.

(Example 34)
<Preparation of polymer film composed of aliphatic polymer compound and aromatic polymer compound>
As the aliphatic polymer compound, polypropylene (F107DV, manufactured by Mitsui Chemicals, Inc.) was used. Polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS ML320p) was used as the aromatic polymer compound.

  70 parts by weight of the aliphatic polymer compound pellets and 30 parts by weight of the aromatic polymer compound pellets were dry blended. The dry blended pellet mixture was melt-extruded under the conditions of a screw temperature of 290 ° C. and a T-die temperature of 290 ° C. using an extruder having a T-die set in a twin-screw kneading extruder to obtain a polymer film (aliphatic (Polypropylene, a high molecular compound, is contained in the polymer film by 70% by weight).

<Preparation of polymer electrolyte membrane>
The polymer film was used. A polymer electrolyte was prepared in the same manner as in Example 17 except that 111 g of 1-chlorobutane and 4.4 g of chlorosulfonic acid were weighed to prepare a 4.0 wt% chlorosulfonic acid solution and the polymer film was 0.26 g. A membrane was obtained (the amount of chlorosulfonic acid added was 17.3 times the weight of the polymer film). The results are shown in Table 3.

(Example 35)
A polymer film obtained in the same manner as in Example 34 was used. Proton conductivity in the same manner as in Example 17 except that 122 g of 1-chlorobutane and 5.5 g of chlorosulfonic acid were weighed to prepare a 4.5 wt% chlorosulfonic acid solution and the polymer film was 0.28 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 19.4 times the weight of the polymer film). The results are shown in Table 3.

(Example 36)
A polymer film obtained in the same manner as in Example 34 was used. Proton conductivity in the same manner as in Example 17 except that 119 g of 1-chlorobutane and 6.0 g of chlorosulfonic acid were weighed to prepare a 5.0 wt% chlorosulfonic acid solution and the polymer film was 0.28 g. A polymer electrolyte membrane was obtained (the amount of chlorosulfonic acid added was 21.6 times the weight of the polymer film). The results are shown in Table 3.

(Comparative Example 5)
<Preparation of polymer film composed of aromatic polymer compound>
As an aromatic polymer compound, polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS LD10p11) was used.

The pellets of the aromatic polymer compound were melt-extruded with an extruder in which a T-die was set in a twin-screw kneading extruder under the conditions of a screw temperature of 290 ° C. and a T-die temperature of 290 ° C. to obtain a polymer film. .

<Preparation of polymer electrolyte membrane>
The polymer film was used. 119 g of 1-chlorobutane and 1.2 g of chlorosulfonic acid were weighed to prepare a 1.0 wt% chlorosulfonic acid solution, and a polymer electrolyte was prepared in the same manner as in Example 17 except that the polymer film was 0.28 g. A membrane was obtained (the amount of chlorosulfonic acid added was 4.3 times the weight of the polymer film). The results are shown in Table 3.

(Comparative Example 6)
<Preparation of polymer film composed of aromatic polymer compound>
Polyphenylene sulfide (Dainippon Ink Industries, Ltd., DIC-PPS ML320p) was used as the aromatic polymer compound.

  The pellets of the aromatic polymer compound were melt-extruded with an extruder in which a T-die was set in a twin-screw kneading extruder under the conditions of a screw temperature of 290 ° C. and a T-die temperature of 290 ° C. to obtain a polymer film. .

<Preparation of polymer electrolyte membrane>
The polymer film was used. A polymer electrolyte was prepared in the same manner as in Example 17 except that 128 g of 1-chlorobutane and 1.9 g of chlorosulfonic acid were weighed to prepare a 1.5 wt% chlorosulfonic acid solution and the polymer film was changed to 0.30 g. A membrane was obtained (the amount of chlorosulfonic acid added was 6.5 times the weight of the polymer film). The results are shown in Table 3.

  From comparison between Examples 17 to 36 in Table 3 and Comparative Examples 5 and 6, the proton conductive polymer electrolyte membrane of the present invention has proton conductivity in the same order as that of the conventional polymer electrolyte membrane. It became clear that it was useful as an electrolyte membrane.

  From the comparison between Examples 17 to 33 and Comparative Example 5 in Table 3 and the comparison between Examples 34 to 36 and Comparative Example 6, the polymer electrolyte membrane of the present invention has a methanol permeability coefficient higher than that of the conventional polymer electrolyte membrane. Is low and shows a high methanol barrier coefficient, indicating that it is useful as a polymer electrolyte membrane for direct methanol fuel cells.

It is principal part sectional drawing of the polymer electrolyte fuel cell (direct methanol fuel cell) of this invention. It is principal part sectional drawing of the direct methanol type fuel cell of this invention. It is a transmission electron microscope image of the cross section of the polymer film (Example 1) of this invention. It is a transmission electron microscope image of the cross section of the polymer film (Example 2) of this invention. It is a transmission electron microscope image of the cross section of the polymer film (Example 3) of this invention. It is a transmission electron microscope image of the cross section of the polymer film (Example 4) of this invention. It is a transmission electron microscope image of the cross section of the polymer film (Example 5) of this invention. It is a transmission electron microscope image of the cross section of the polymer film (Example 6) of this invention. It is a transmission electron microscope image of the cross section of the polymer film (Example 7) of this invention. It is a transmission electron microscope image of the cross section of the polymer film (Example 8) of this invention. It is a transmission electron microscope image of the cross section of the polymer film (Example 9) of this invention. It is a transmission electron microscope image of the cross section of the polymer film (Example 10) of this invention. 1 is an embodiment of a cross-sectional view of a main part of a polymer electrolyte fuel cell (direct methanol fuel cell) of the present invention. It is one aspect | mode sectional view of the principal part of the direct methanol fuel cell of this invention. The power generation characteristic evaluation result of the direct methanol type fuel cell of Example 23 of the present invention. The electric power generation characteristic evaluation result of the direct methanol fuel cell of Example 25 of this invention. The power generation characteristic evaluation result of the direct methanol fuel cell of Example 28 of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Polymer electrolyte membrane 2 Catalyst layer 3 Diffusion layer 4 Separator 5 Flow path 6 Membrane-electrode assembly (MEA)
DESCRIPTION OF SYMBOLS 7 Fuel tank 8 Fuel filling part 9 Support body 10 Oxidant flow path 21 Proton conductive polymer membrane 22 Catalyst carrying | support gas diffusion electrode 23 Flow path 24 Separator 25 Proton conductive polymer film 26 Catalyst carry | support gas diffusion electrode 27 Fuel tank 28 Fuel filling part 29 Support body 30 Oxidant flow path

  According to the present invention, high proton conductivity and high methanol blocking are achieved by a polymer electrolyte membrane composed of at least two compounds of an aliphatic polymer compound and an aromatic polymer compound containing a proton conductive group. It became possible to express sex. These have excellent proton conductivity and high methanol barrier properties, and are useful as polymer electrolyte membranes for solid polymer fuel cells, direct liquid fuel cells, and direct methanol fuel cells. Moreover, it became possible to implement | achieve said polymer electrolyte membrane by using the polymer film of this invention as a material.

  According to the present invention, in a polymer film comprising at least three polymer compounds as essential components, a polymer compound having an aromatic unit, a thermoplastic elastomer, and a polymer compound having no aromatic unit. Polymer electrolyte membranes with proton conductive groups introduced into aromatic units have excellent proton conductivity and high methanol barrier properties, such as solid polymer fuel cells, direct liquid fuel cells, and direct methanol fuels It is useful as a polymer electrolyte membrane for batteries. Moreover, it became possible to implement | achieve said polymer electrolyte membrane by using the polymer film of this invention as a material.

According to the present invention, it comprises at least two polymer compounds, a polymer compound having an aromatic unit and a polymer compound having no aromatic unit,
A proton conductive group is introduced into the aromatic unit in the polymer film having a structure in which the polymer compound having the aromatic unit is dispersed in the polymer compound having no aromatic unit. The polymer electrolyte membrane has excellent proton conductivity and high methanol barrier properties, and is useful as a polymer electrolyte membrane for solid polymer fuel cells, direct liquid fuel cells, and direct methanol fuel cells. Moreover, it became possible to implement | achieve said polymer electrolyte membrane by using the polymer film of this invention as a material.

Claims (23)

A polymer electrolyte membrane material used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell,
(A) a polymer compound having an aromatic unit,
(B) a polymer compound having no aromatic unit,
A polymer film containing as an essential component ,
The polymer film formed by film-forming the mixture of said (A) and said (B) . The polymer film according to claim 1, further comprising (C) a thermoplastic elastomer as an essential component. The (A) is at least one selected from the group consisting of polystyrene, syndiotactic polystyrene, polyphenylene ether, modified polyphenylene ether, polysulfone, polyether sulfone, polyether ether ketone and polyphenylene sulfide, and derivatives thereof. The polymer film according to claim 1, wherein the polymer film is characterized. The polymer film according to any one of claims 1 to 3, wherein (A) is at least one selected from the group consisting of polystyrene, syndiotactic polystyrene, and polyphenylene sulfide. (B) is represented by the following general formula (1)
_(Wherein, X _{1 to 4 is,} H, based on any one of CH 3, Cl, F, OCOCH 3, CN, COOH, COOCH 3, OC 4 H 9, is selected from the group consisting _{of, X. 1 to} The polymer film according to any one of claims 1 to 4, wherein the polymer film is at least one selected from polymer compounds comprising ₄ independently of each other and may be the same or different. . The polymer film according to any one of claims 1 to 5, wherein (B) is at least one selected from the group consisting of polyethylene, polypropylene, polymethylpentene, and derivatives thereof. . The polymer according to any one of claims 2 to 6, wherein (C) is a copolymer of polystyrene or a polystyrene derivative and the following general formula (2) and / or general formula (3): the film.
(In the formula, R _1-12 is C _x H _{2x + 1} , and R _1-12 may be the same or different from each other, and l, m, n, and x are integers of 0 or more. .) Said (C) is polystyrene-polyisobutylene-polystyrene triblock copolymer, polystyrene-poly (ethylene / propylene) block copolymer, polystyrene-poly (ethylene / propylene) -polystyrene triblock copolymer, polystyrene-poly ( It is at least one selected from the group consisting of ethylene / butylene) -polystyrene triblock copolymers and polystyrene-poly (ethylene-ethylene / propylene) -polystyrene triblock copolymers, and derivatives thereof. The polymer film according to any one of claims 2 to 7. The polymer film according to claim 1, wherein (B) is contained in an amount of 10% by weight to 95% by weight. The polymer film according to claim 1, wherein the (A) is dispersed in the (B). It is a polymer electrolyte membrane used for a solid polymer fuel cell, a direct liquid fuel cell, and a direct methanol fuel cell, and the aromatic present in the polymer film according to any one of claims 1 to 10. A polymer electrolyte membrane, wherein a proton conductive group is introduced into a unit. 12. The polymer electrolyte membrane according to claim 11, wherein the proton conductive group is a sulfonic acid group. 13. The polymer electrolyte membrane according to claim 11, wherein an ion exchange capacity of the polymer electrolyte membrane is 0.5 to 3.0 meq / g. The polymer electrolyte membrane according to claim 11, wherein the polymer electrolyte membrane has a proton conductivity at 23 ° C. of 1.0 × 10 ⁻³ S / cm or more. The high permeability according to any one of claims 11 to 14, wherein the polymer electrolyte membrane has a methanol permeability coefficient of 2,000 µmol / (cm · day) or less with respect to a 64 wt% methanol aqueous solution at 25 ° C. Molecular electrolyte membrane. Used for polymer electrolyte fuel cells, direct liquid fuel cells, direct methanol fuel cells,
It is a manufacturing method of the material of a polymer electrolyte membrane, Comprising: The polymer film in any one of the said Claims 1-10 is manufactured by melt extrusion molding, The manufacturing method of the polymer film characterized by the above-mentioned. Used for polymer electrolyte fuel cells, direct liquid fuel cells, direct methanol fuel cells,
A method for producing a polymer electrolyte membrane, wherein the polymer film according to any one of claims 1 to 10 is contacted with a sulfonating agent in the presence of an organic solvent. Method. The method for producing a polymer electrolyte membrane according to claim 17, wherein the sulfonating agent is chlorosulfonic acid. The method for producing a polymer electrolyte membrane according to any one of claims 17 and 18, wherein the organic solvent is a halogenated hydrocarbon. The polymer electrolyte according to any one of claims 17 to 19, wherein the halogenated hydrocarbon is at least one selected from the group consisting of dichloromethane, 1,2-dichloroethane and 1-chlorobutane. A method for producing a membrane. The polymer electrolyte membrane according to any one of claims 11 to 15 or the polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of claims 17 to 20 is used. A polymer electrolyte fuel cell characterized by the above. The polymer electrolyte membrane according to any one of claims 11 to 15 or the polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of claims 17 to 20 is used. A direct liquid fuel cell. The polymer electrolyte membrane according to any one of claims 11 to 15 or the polymer electrolyte membrane obtained by the method for producing a polymer electrolyte membrane according to any one of claims 17 to 20 is used. A direct methanol fuel cell.