JP2005126638A - Polymer composition, polymer solution composition and composite film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polymer composition which can maintain a gas barrier property without deteriorating proton conductivity when made it into a film and can improve strength and toughness of a film that consists of only sulfonated polyarylene, a polymer solution composition and a composite film obtained from these compositions. <P>SOLUTION: The polymer composition comprises (a) a tetrafluoroethylene copolymer having proton conductivity, and (b) a polyarylene having a sulfonic acid group wherein the polyarylene has repeating units represented by formula (2). The polymer solution composition comprises a (a) component, a (b) component and (c) an organic solvent. The composite film is obtained by applying the polymer solution composition onto a substrate and drying it. In formula (2), A is a divalent electron attractive group, B is a divalent electron-releasing group or a direct bond, Ar is an aromatic group having a substituent expressed by -SO<SB>3</SB>H, m is 0-10, n is 0-10, and k is 1-4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is obtained from, for example, a polymer composition containing a polyarylene having a sulfonic acid group suitably used for proton conductive membrane applications, a polymer solution composition, and these compositions, without impairing proton conductivity. The present invention relates to a composite membrane that improves the strength and toughness of a membrane composed only of polyarylene having a sulfonic acid group while maintaining gas barrier properties.

  The electrolyte is usually used in a (water) solution. However, in recent years, there is an increasing tendency to replace this with a solid system. The first reason is, for example, the ease of processing when applied to electrical / electronic materials, and the second reason is the shift to electronic devices that are lighter, thinner, smaller, and higher in power.

  Conventionally, both proton-conducting materials made of inorganic substances and organic substances are known. Examples of inorganic substances include, for example, uranyl phosphate, which is a hydrated compound, but these inorganic compounds do not have sufficient contact at the interface, and there are many problems in forming a conductive layer on a substrate or electrode.

  On the other hand, examples of organic compounds include polymers belonging to so-called cation exchange resins, for example, sulfonated vinyl polymers such as polystyrene sulfonic acid, perfluoroalkyl sulfonic acid polymers represented by Nafion (trademark, manufactured by DuPont), Examples include perfluoroalkylcarboxylic acid polymers, and organic polymers such as polymers in which sulfonic acid groups or phosphoric acid groups are introduced into heat-resistant polymers such as polybenzimidazole and polyetheretherketone (see Non-Patent Documents 1 to 3). .

  These organic polymers are usually used in the form of a film, but a conductive film can be bonded on the electrode by utilizing the solubility in a solvent or the fact that it is thermoplastic. However, in many of these organic polymers, proton conductivity is not yet sufficient, durability, proton conductivity at high temperature (100 ° C. or higher) is reduced, and the dependence on humidity conditions is large. In addition, there are problems that the adhesion to the electrode is not sufficiently satisfactory, or the strength is reduced due to excessive swelling during operation due to the water-containing polymer structure, and the shape is collapsed. Therefore, these organic polymers have various problems when applied to the above-mentioned electric / electronic materials.

  Furthermore, a solid polymer electrolyte made of sulfonated rigid polyphenylene (that is, a sulfonated product having a polyarylene structure as a main component) has been proposed (see Patent Document 1). This polymer is mainly composed of a polymer composed of a phenylene chain obtained by polymerizing an aromatic compound (structure described in Patent Document 1, column 9), and this is reacted with a sulfonating agent to introduce a sulfonic acid group. . However, although the proton conductivity is improved by increasing the amount of introduced sulfonic acid groups, the mechanical properties of the resulting sulfonated polymer are significantly impaired. Therefore, it is necessary to adjust an appropriate sulfonation concentration that maintains excellent mechanical properties and exhibits proton conductivity. In fact, with this polymer, the sulfonation reaction is likely to proceed, and it is very difficult to control the appropriate amount of sulfonic acid groups introduced.

Therefore, there is a demand for a composition containing polyarylene having a sulfonic acid group that maintains excellent mechanical properties and exhibits proton conductivity.
Polymer Preprints, Japan, Vol.42, No.7, p.2490-2492 (1993) Polymer Preprints, Japan, Vol.43, No.3, p.735-736 (1994) Polymer Preprints, Japan, Vol. 42, No. 3, p730 (1993) US Pat. No. 5,403,675

  An object of the present invention is, for example, a polymer capable of maintaining gas barrier properties without impairing proton conductivity when a proton conducting membrane is prepared, and further improving the strength and toughness of a membrane comprising a sulfonated polyarylene. It is an object of the present invention to provide a composition, a polymer solution composition, and a composite film excellent in gas barrier properties, film strength and toughness obtained from these compositions.

According to the present invention, the following polymer composition, polymer solution composition and composite film are provided, and the above-mentioned problems of the present invention are solved.
(1)
A polymer comprising (a) a tetrafluoroethylene copolymer having proton conductivity, and (b) a polyarylene having a sulfonic acid group having a repeating unit represented by the following general formula (2): Composition;

(In the formula, A represents a divalent electron-withdrawing group, B represents a divalent electron-donating group or a direct bond, Ar represents an aromatic group having a substituent represented by —SO ₃ H, m represents an integer of 0 to 10, n represents an integer of 0 to 10, and k represents an integer of 1 to 4.
(2)
The polymer composition according to (1) above, wherein the (a) tetrafluoroethylene copolymer having proton conductivity comprises a structural unit represented by the following general formula (1);

(Wherein x is a number from 1 to 30, y is a number from 10 to 2,000, m is a number from 0 to 10, and n is from 1 to 1
The number 0, A represents —SO ₃ Z or —COOZ (where Z is a hydrogen atom or an alkali metal atom). )
(3)
(B) The polyarylene having a sulfonic acid group has a repeating unit represented by the following general formula (3) in addition to the repeating unit represented by the general formula (2). 1) or a polymer composition according to (2);

(Wherein R ^{1 to} R ⁸ may be the same or different from each other, and at least one selected from the group consisting of a hydrogen atom, a fluorine atom, an alkyl group, a fluorine-substituted alkyl group, an allyl group, an aryl group, and a cyano group) W represents a divalent electron-withdrawing group or a single bond, T represents a single bond or a divalent organic group, and p represents an integer of 2 or more when T is —O—. In the case other than -O-, an integer of 1 or more is shown.)
(4)
When the total of (a) the tetrafluoroethylene copolymer having proton conductivity and (b) the polyarylene having a sulfonic acid group having a repeating unit represented by the general formula (2) is 100% by weight The polymer composition according to any one of (1) to (3), further comprising 5 to 90% by weight of the component (a) and 95 to 10% by weight of the component (b).
(5)
A composite film obtained from the polymer composition according to any one of (1) to (4) above.
(6)
The composite membrane according to (5) above, which is a proton conducting membrane.
(7)
(A) containing a tetrafluoroethylene copolymer having proton conductivity, (b) a polyarylene having a sulfonic acid group having a repeating unit represented by the general formula (2), and (c) an organic solvent. A polymer solution composition characterized by the above.
(8)
The polymer solution composition (9) according to the above (7), wherein the (a) tetrafluoroethylene copolymer having proton conductivity comprises a structural unit represented by the general formula (1).
(B) The polyarylene having a sulfonic acid group has a repeating unit represented by the following general formula (3) in addition to the repeating unit represented by the general formula (2). The polymer solution composition (10) according to 7) or (8)
When the total of (a) a tetrafluoroethylene copolymer having proton conductivity and (b) a sulfonic acid group-containing polyarylene having a repeating unit represented by the general formula (2) is 100% by weight, The polymer solution composition (11) according to any one of the above (7) to (9), which contains 5 to 90% by weight of the component (a) and 95 to 10% by weight of the component (b).
A composite film obtained by applying the polymer solution composition according to any one of (7) to (10) above to a substrate and drying it.
(12)
The composite membrane according to (11) above, which is a proton conducting membrane.

Since the polymer composition of the present invention contains an elastomeric (a) tetrafluoroethylene copolymer having proton conductivity and a resinous (b) polyarylene having a sulfonic acid group, The obtained composite membrane can improve strength and toughness as compared with a membrane made only of polyarylene having a sulfonic acid group while maintaining gas barrier properties without impairing proton conductivity.

  The polymer solution composition of the present invention comprises an elastomeric (a) proton conductive tetrafluoroethylene copolymer, a resinous (b) polyarylene having a sulfonic acid group, and (c) an organic material. Since the component (a) and the component (b) are homogenized in a solution state, the composite membrane obtained from the solvent maintains gas barrier properties without impairing proton conductivity, The strength and toughness can be improved as compared with a film composed only of polyarylene having a sulfonic acid group.

  The composite membrane of the present invention has high pronton conductivity over a wide temperature range as a conductive membrane, and has excellent adhesion to a substrate and an electrode, is not brittle and excellent in strength, and is used for an electrolyte for a primary battery and a secondary battery. It can be used as a conductive membrane such as an electrolyte, a solid polymer electrolyte for fuel cells, a display element, various sensors, a signal transmission medium, a solid capacitor, and an ion exchange membrane, and its industrial significance is extremely large.

[Polymer composition]
The polymer composition of the present invention comprises (a) a tetrafluoroethylene copolymer having proton conductivity and (b) a polyarylene having a sulfonic acid group as main components.

(A) a tetrafluoroethylene copolymer having proton conductivity;
The (a) proton conductive tetrafluoroethylene copolymer constituting the polymer composition of the present invention is, for example, a copolymer having a repeating unit represented by the following formula (1) as a main repeating unit. .

In the formula, x represents a number of 1 to 30, preferably 1 to 20.
y represents a number of 10 to 2,000, preferably 100 to 1,000.
m represents a number of 0 to 10, preferably 0 to 5.
n represents a number of 1 to 10, preferably 1 to 5.
A represents —SO ₃ Z or —COOZ. Here, Z is a hydrogen atom or an alkali metal atom such as sodium or potassium.

Here, when x is less than 1, the copolymer becomes water-soluble. On the other hand, when it exceeds 30, the proton conductivity of the copolymer decreases. On the other hand, if y is less than 10, the proton conductivity of the copolymer is lowered. On the other hand, when it exceeds 2,000, the mechanical strength of the copolymer decreases. Furthermore, when m exceeds 10, the proton conductivity of the copolymer decreases. On the other hand, when n exceeds 5, the proton conductivity of the copolymer decreases.

This (a) tetrafluoroethylene copolymer having proton conductivity is obtained by, for example, hydrolyzing a copolymer of tetrafluoroethylene and a perfluorovinyl ether having a sulfonyl fluoride group at the terminal, thereby obtaining the sulfonyl fluoride group. Is a sulfonated polymer having a sulfonate group, or a carboxylated polymer in which a part or all of the sulfonate groups of the sulfonated polymer are substituted with carboxyl groups.

  (A) The ion exchange capacity in the tetrafluoroethylene copolymer having proton conductivity is preferably 0.7 to 1.5 meq / g, more preferably 0.8 to 1.2 meq / g.

(A) As a specific example of the tetrafluoroethylene copolymer having proton conductivity, Nafion (trade name, x = 5 to 13.5, y = 1,000, m ≧ 1, n, manufactured by DuPont, USA) = 2, ion exchange capacity = 0.91 meq / g, A = -SO ₃ H), commonly known Dow membrane manufactured by Dow Chemical Company (m = 0, n = 2, ion exchange capacity = 0.8 meq / g, A = -SO ₃ H), Acipex (trade name) manufactured by Asahi Kasei Kogyo Co., Ltd. (x = 1.5 to 1)
4, m = 0-3, n = 2-5, ion exchange capacity = 0.9-1.0 meq / g, A = —SO ₃ H, —COOH), Flemion manufactured by Asahi Glass Co., Ltd. Name) (m = 0
˜1, n = 1 to 5, ion exchange capacity = 0.9 meq / g, A = —COOH) and the like.

(B) a polyarylene having a sulfonic acid group;
The polyarylene (b) having a sulfonic acid group constituting the polymer composition of the present invention has a repeating structural unit represented by the following general formula (2) as a main structural unit, and if necessary, the following general formula (3 ) Is included.

In the formula (2), A represents a divalent electron withdrawing group, specifically, —CO—, —SO ₂ —, —S.
O—, —CONH—, —COO—, — (CF ₂ ) ₁ — (wherein 1 is an integer of 1 to 10), —C (CF ₃ ) ₂ — and the like can be mentioned.
B represents a divalent electron-donating group or a direct bond. Specific examples of the electron-donating group include — (CH ₂
)-, -C (CH ₃ ) _2- , -O-, -S-, -CH = CH-, -C≡C- and

Etc.
The electron-withdrawing group is a Hammett substituent constant when the phenyl group is in the m-position.
In the case of 0.06 or more and p-position, it means a group having a value of 0.01 or more.
Ar represents an aromatic group having a substituent represented by —SO ₃ H, and specific examples of the aromatic group include a phenyl group, a naphthyl group, an anthracenyl group, and a phenanthyl group. Of these groups, a phenyl group and a naphthyl group are preferable.
m represents an integer of 0 to 10, preferably 0 to 2, n represents an integer of 0 to 10, preferably 0 to 2, and k represents an integer of 1 to 4.

In formula (3), R ^{1 to} R ⁸ may be the same as or different from each other, and are selected from the group consisting of a hydrogen atom, a fluorine atom, an alkyl group, a fluorine-substituted alkyl group, an allyl group, an aryl group, and a cyano group. At least one atom or group is shown.
Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, an amyl group, and a hexyl group, and a methyl group and an ethyl group are preferable.
Examples of the fluorine-substituted alkyl group include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluorobutyl group, perfluoropentyl group, perfluorohexyl group, trifluoromethyl group, pentafluoroethyl group, and the like. Etc. are preferable.
Examples of allyl groups include propenyl groups,
Examples of the aryl group include a phenyl group and a pentafluorophenyl group.

W represents a single bond or a divalent electron-withdrawing group. Examples of the divalent electron withdrawing group include the same ones as described above.
T represents a single bond or a divalent organic group. Specific examples of the divalent organic group include an electron-withdrawing group and an electron-donating group, and examples of the electron-withdrawing group and the electron-donating group include those described above.

  In Formula (3), p is an integer of 2 or more when T is —O—, and is an integer of 1 or more when T is other than —O—, and the upper limit is usually 100, preferably 10 to 80.

  The polyarylene (b) having a sulfonic acid group constituting the polymer composition of the present invention is, for example, a polymer represented by the following general formula (4).

(In the formula (4), W, T, A, B, Ar, m, n, k, p and R ^{1 to} R ⁸ are respectively W, T, A in the general formulas (2) and (3). , B, Ar, m, n, k, p, and R ^{1 to} R ⁸ .
(B) The polyarylene having a sulfonic acid group used in the present invention is a proportion of 0.5 to 100 mol%, preferably 10 to 99.999 mol%, of the repeating structural unit represented by the general formula (2). The repeating structural unit represented by the general formula (3) is contained in a ratio of 99.5 to 0 mol%, preferably 90 to 0.001 mol%.

  (B) The polyarylene having a sulfonic acid group includes a monomer having a sulfonic ester group that can be a structural unit represented by the general formula (2) and an oligomer that can be a structural unit represented by the general formula (3). To produce a polyarylene having a sulfonic acid ester group, hydrolyzing the polyarylene having the sulfonic acid ester group, and converting the sulfonic acid ester group into a sulfonic acid group. it can.

  In addition, (b) a polyarylene having a sulfonic acid group has a skeleton represented by the above general formula (2), a structural unit having no sulfonic acid group or sulfonic acid ester group, and the above general formula (3) It is also possible to synthesize a polyarylene composed of structural units in advance and sulphonate the polymer.

  When a polyarylene having a sulfonate group is synthesized by copolymerizing a monomer that can be a structural unit of the general formula (2) and an oligomer that can be a structural unit of the general formula (3), the general formula ( As the monomer that can be a structural unit of 2), for example, a sulfonate ester represented by the following general formula (5) (hereinafter also referred to as “monomer (5)”) is used.

In the formula (5), X represents a halogen atom other than fluorine (chlorine, bromine, iodine), —OSO ₂ Z (
Here, Z represents an alkyl group, a fluorine-substituted alkyl group or an aryl group. A, B, m, n and k have the same meanings as A, B, m, n and k in the general formula (2), respectively. R ^a represents a hydrocarbon group having 1 to 20 carbon atoms, preferably 4 to 20 carbon atoms, specifically, methyl group, ethyl group, n-propyl group, iso-propyl group, tert-butyl group, iso- Butyl group, n-butyl group, sec-butyl group, neopentyl group, cyclopentyl group, hexyl group, cyclohexyl group, cyclopentylmethyl group, cyclohexylmethyl group, adamantyl group, adamantanemethyl group, 2-ethylhexyl group, bicyclo [2.2 .1] heptyl group, bicyclo [2.2.1] heptylmethyl group, tetrahydrofurfuryl group, 2-methylbutyl group, 3,3-dimethyl-2,4-dioxolanemethyl group, cyclohexylmethyl group, adamantylmethyl group , Straight chain hydrocarbon groups such as bicyclo [2.2.1] heptylmethyl group, branched hydrocarbon groups, alicyclic carbon groups Examples thereof include a hydrogen group and a hydrocarbon group having a 5-membered heterocyclic ring. Among these, an n-butyl group, neopentyl group, tetrahydrofurfuryl group, cyclopentyl group, cyclohexyl group, cyclohexylmethyl group, adamantylmethyl group, and bicyclo [2.2.1] heptylmethyl group are preferable, and a neopentyl group is more preferable. .

Ar ′ represents an aromatic group having a sulfonate group represented by —SO ₃ R ^b , and specific examples of the aromatic group include a phenyl group, a naphthyl group, an anthracenyl group, and a phenanthyl group. Of these groups, a phenyl group and a naphthyl group are preferable.
The sulfonate group —SO ₃ R ^b is substituted with one or more aromatic groups, and when two or more substituents —SO ₃ R ^b are substituted, these sulfonate esters are substituted. The groups may be the same or different from each other.

Here, R ^b represents a hydrocarbon group having 1 to 20 carbon atoms, preferably 4 to 20 carbon atoms, and specific examples thereof include the hydrocarbon groups having 1 to 20 carbon atoms. Among these, an n-butyl group, neopentyl group, tetrahydrofurfuryl group, cyclopentyl group, cyclohexyl group, cyclohexylmethyl group, adamantylmethyl group, and bicyclo [2.2.1] heptylmethyl group are preferable, and a neopentyl group is more preferable. .
Specific examples of the sulfonic acid ester represented by the general formula (5) include the following compounds.

In addition, as the sulfonate ester represented by the general formula (5), a compound in which a chlorine atom is replaced with a bromine atom in the above compound, a compound in which —CO— is replaced with —SO ₂ — in the above compound, and chlorine in the above compound atom is replaced by a bromine atom, and -CO- is -SO ₂ - can also be mentioned such compounds replaced.

The R ^b group in the general formula (5) is derived from a primary alcohol, and the β carbon is a tertiary or quaternary carbon, which is excellent in stability during the polymerization process and produces sulfonic acid by deesterification. It is preferable in that it does not cause polymerization inhibition or cross-linking due to the above, and it is preferable that these ester groups are derived from primary alcohols and the β-position is a quaternary carbon.

  Specific examples of the compound having the same skeleton as the sulfonic acid ester represented by the general formula (5) and having no sulfonic acid group or sulfonic acid ester group include the following compounds.

A compound in which a chlorine atom is replaced with a bromine atom in the above compound, a compound in which —CO— is replaced with —SO ₂ — in the above compound, a chlorine atom is replaced with a bromine atom in the above compound, and —CO— is replaced with —SO ₂ —. Examples include substituted compounds.

  As the oligomer that can be the structural unit of the general formula (3), for example, a compound represented by the following general formula (6) (hereinafter also referred to as “oligomer (6)”) is used.

In formula (6), R < ¹ > -R < ⁸ >, W, T, and p are synonymous with R < ¹ > -R < ⁸ >, W, T, and p in the said general formula (3), respectively.

R ′ and R ″ may be the same or different from each other, and are represented by a halogen atom excluding a fluorine atom or —OSO ₂ Z (wherein Z represents an alkyl group, a fluorine-substituted alkyl group or an aryl group). Represents a group. Examples of the alkyl group represented by Z include a methyl group and an ethyl group, examples of the fluorine-substituted alkyl group include a trifluoromethyl group, and examples of the aryl group include a phenyl group and a p-tolyl group.

The compound represented by the general formula (6) includes 2,2-bis [4- {4- (4-chlorobenzoyl) phenoxy} phenyl] -1,1,1,3,3,3-hexafluoro. propane,
Examples include bis [4- {4- (4-chlorobenzoyl) phenoxy} phenyl] sulfone, compounds represented by the following formulas, and the like.

The compound represented by the general formula (6) can be synthesized, for example, by the method shown below.
First, in order to convert the bisphenol linked with an electron-withdrawing group into the corresponding alkali metal salt of bisphenol, dielectrics such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, sulfolane, diphenylsulfone, dimethylsulfoxide, etc. Add an alkali metal such as lithium, sodium or potassium, an alkali metal hydride, an alkali metal hydroxide, an alkali metal carbonate or the like in a polar solvent having a high rate.

Usually, the alkali metal is reacted in excess with respect to the hydroxyl group of phenol, and usually 1.1 to 2 times equivalent is used. Preferably, 1.2 to 1.5 times equivalent is used. In this case, fluorine, chlorine, etc. activated with an electron-withdrawing group in the presence of azeotropic solvent such as benzene, toluene, xylene, hexane, cyclohexane, octane, chlorobenzene, dioxane, tetrahydrofuran, anisole, phenetole, etc. Aromatic halogen-substituted aromatic dihalide compounds such as 4,4′-difluorobenzophenone, 4,4′-dichlorobenzophenone, 4,4′-chlorofluorobenzophenone, bis (4-chlorophenyl) sulfone, bis (4 -Fluorophenyl) sulfone, 4-fluorophenyl-4'-chlorophenylsulfone, bis (3-nitro-4-chlorophenyl) sulfone, 2,6-dichlorobenzonitrile, 2,6-difluorobenzonitrile, hexafluorobenzene, deca Fluorobiphenyl, , 5-difluorobenzophenone, 1,3-bis (4-chlorobenzoyl) reacting benzene. In terms of reactivity, a fluorine compound is preferable, but in consideration of the following aromatic coupling reaction, it is necessary to assemble an aromatic nucleophilic substitution reaction so that the terminal is a chlorine atom. The active aromatic dihalide is used in an amount of 2 to 4 times mol, preferably 2.2 to 2.8 times mol, of bisphenol. Prior to the aromatic nucleophilic substitution reaction, an alkali metal salt of bisphenol may be used. The reaction temperature is 60 ° C to 300 ° C, preferably 80 ° C to 250 ° C. The reaction time ranges from 15 minutes to 100 hours, preferably from 1 hour to 24 hours. The most preferable method is to use a chlorofluoro compound having one halogen atom having a different reactivity as the active aromatic dihalide represented by the following formula, and a nucleophilic substitution reaction with phenoxide occurs preferentially by the fluorine atom. It is convenient to obtain the desired activated terminal chloro form.

(Wherein, W is as defined for general formula (6).)
In addition, as a method for synthesizing the compound represented by the general formula (6), as described in JP-A-2-159, a nucleophilic substitution reaction and an electrophilic substitution reaction are combined to obtain a target electron withdrawing property. There is a method of synthesizing a flexible compound composed of a group and an electron donating group.
Specifically, an aromatic bishalide activated with an electron-withdrawing group, for example, bis (4-chlorophenyl) sulfone is subjected to a nucleophilic substitution reaction with phenol to obtain a bisphenoxy substitution product. Subsequently, the compound of interest is obtained by Friedel-Craft reaction of this bisphenoxy-substituted product with, for example, 4-chlorobenzoic acid chloride. As the aromatic bishalide activated with the electron-withdrawing group used here, the compounds exemplified above can be applied. Although phenol may be substituted, an unsubstituted compound is preferable from the viewpoint of heat resistance and flexibility. In addition, it is preferable to use an alkali metal salt for the phenol substitution reaction, and the compounds exemplified above can be used as the alkali metal compound. The amount used is 1.2 to 2 moles per mole of phenol. In the reaction, the polar solvent described above or an azeotropic solvent with water can be used. In the Friedel-Crafts reaction, the bisphenoxy-substituted product is reacted with chlorobenzoic acid chloride as an acylating agent in the presence of an activator for the Lewis acid Friedel-Crafts reaction such as aluminum chloride, boron trifluoride, and zinc chloride. . Chlorobenzoic acid chloride is used in an amount of 2 to 4 times mol, preferably 2.2 to 3 times mol, of the bisphenoxy-substituted product. The Friedel-Craft activator is used in an amount of 1.1 to 2 times equivalent to 1 mol of an active halide compound such as chlorobenzoic acid as an acylating agent. The reaction time ranges from 15 minutes to 10 hours, and the reaction temperature ranges from -20 ° C to 80 ° C. As the solvent used, chlorobenzene, nitrobenzene and the like which are inert to Friedel-Crafts reaction can be used.

In the general formula (6), the compound in which p is 2 or more is, for example, a bisphenol serving as a source of etheric oxygen that is the electron donating group T in the general formula (6) and an electron withdrawing group W. A compound in combination with at least one group selected from> C═O, —SO ₂ — and> C (CF ₃ ) ₂ , specifically 2,2-bis (4-hydroxyphenyl) -1,1 1,3,3,3-hexafluoropropane, alkali metal salts of bisphenols such as 2,2-bis (4-hydroxyphenyl) ketone, 2,2-bis (4-hydroxyphenyl) sulfone and an excess of 4 Substitution reactions with active aromatic halogen compounds such as 1,4-dichlorobenzophenone and bis (4-chlorophenyl) sulfone can be performed using N-methyl-2-pyrrolidone, N, N-dimethylacetamide, sulfolane, etc. In the presence of a neutral solvent, it is obtained by sequential polymerization in the monomer synthesis method.
Examples of such compounds include compounds represented by the following formulas.

  In the above, p is a positive integer, and the upper limit is usually 100, preferably 10-80.

  The polyarylene having a sulfonate group represented by the general formula (4) is synthesized by reacting the monomer (5) and the oligomer (6) in the presence of a catalyst. Is a catalyst system containing a transition metal compound. This catalyst system includes (i) a compound that becomes a transition metal salt and a ligand (hereinafter referred to as “ligand component”) or a ligand. The transition metal complex (including copper salt) and (ii) the reducing agent are essential components, and a “salt” may be added to increase the polymerization rate.

  Here, as the transition metal salt, nickel compounds such as nickel chloride, nickel bromide, nickel iodide and nickel acetylacetonate; palladium compounds such as palladium chloride, palladium bromide and palladium iodide; iron chloride and iron bromide And iron compounds such as iron iodide; cobalt compounds such as cobalt chloride, cobalt bromide, and cobalt iodide. Of these, nickel chloride, nickel bromide and the like are particularly preferable.

As the ligand component, triphenylphosphine, 2,2′-bipyridine, 1,5-
Examples include cyclooctadiene and 1,3-bis (diphenylphosphino) propane. Of these, triphenylphosphine and 2,2′-bipyridine are preferred. The compound which is the said ligand component can be used individually by 1 type or in combination of 2 or more types.

Furthermore, as the transition metal complex in which the ligand is coordinated, for example, nickel chloride bis (triphenylphosphine), nickel bromide bis (triphenylphosphine), nickel iodide bis (triphenylphosphine), nickel nitrate bis (Triphenylphosphine), nickel chloride (2,2'-bipyridine), nickel bromide (2,2'-bipyridine), nickel iodide (2,2'-bipyridine), nickel nitrate (2,2'-bipyridine) ), Bis (1,5-cyclooctadiene) nickel, tetrakis (triphenylphosphine) nickel, tetrakis (triphenylphosphite) nickel, tetrakis (triphenylphosphine) palladium and the like. Of these, nickel chloride bis (triphenylphosphine) and nickel chloride (2,2′-bipyridine) are preferred.

  Examples of the reducing agent that can be used in the catalyst system include iron, zinc, manganese, aluminum, magnesium, sodium, calcium, and the like. Of these, zinc, magnesium and manganese are preferred. These reducing agents can be used after being more activated by bringing them into contact with an acid such as an organic acid.

  Examples of the “salt” that can be used in the above catalyst system include sodium compounds such as sodium fluoride, sodium chloride, sodium bromide, sodium iodide, sodium sulfate, potassium fluoride, potassium chloride, potassium bromide, Examples include potassium compounds such as potassium iodide and potassium sulfate; ammonium compounds such as tetraethylammonium fluoride, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, and tetraethylammonium sulfate. Of these, sodium bromide, sodium iodide, potassium bromide, tetraethylammonium bromide, and tetraethylammonium iodide are preferred.

  The proportion of each component used is usually from 0.0001 to 10 moles of transition metal salt or transition metal complex with respect to 1 mole of the above monomers (sum of monomers (5) + oligomer (6), the same applies hereinafter), Preferably it is 0.01-0.5 mol. When the amount is less than 0.0001 mol, the polymerization reaction may not proceed sufficiently. On the other hand, when the amount exceeds 10 mol, the molecular weight may decrease.

In the above catalyst system, when a transition metal salt and a ligand component are used, the ratio of the ligand component used is usually 0.1 to 100 mol, preferably 1 to 10 mol, per 1 mol of the transition metal salt. It is. When the amount is less than 0.1 mol, the catalytic activity may be insufficient. On the other hand, when the amount exceeds 100 mol, the molecular weight may decrease.

  Moreover, the usage-amount of a reducing agent is 0.1-100 mol normally with respect to the total of 1 mol of the said monomer, Preferably it is 1-10 mol. If the amount is less than 0.1 mol, polymerization may not proceed sufficiently. If the amount exceeds 100 mol, purification of the resulting polymer may be difficult.

  Furthermore, when using "salt", the usage-ratio is 0.001-100 mol normally with respect to the total of 1 mol of the said monomer, Preferably it is 0.01-1 mol. If it is less than 0.001 mol, the effect of increasing the polymerization rate may be insufficient, and if it exceeds 100 mol, purification of the resulting polymer may be difficult.

Examples of the polymerization solvent that can be used when the monomer (5) and the oligomer (6) are reacted include tetrahydrofuran, cyclohexanone, dimethyl sulfoxide, N,
N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, γ-butyrolactone, N, N′-dimethylimidazolidinone and the like can be mentioned. Of these, tetrahydrofuran, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and N, N′-dimethylimidazolidinone are preferable. These polymerization solvents are preferably used after sufficiently dried.

The total concentration of the monomers in the polymerization solvent is usually 1 to 90% by weight, preferably 5 to 40% by weight.
Moreover, the superposition | polymerization temperature at the time of superposing | polymerizing is 0-200 degreeC normally, Preferably it is 50-120 degreeC. The polymerization time is usually 0.5 to 100 hours, preferably 1 to 40 hours.
The polyarylene having a sulfonic acid ester group obtained by using the monomer (5) can be converted into a polyarylene having a sulfonic acid group by hydrolyzing the sulfonic acid ester group and converting it to a sulfonic acid group. .

Hydrolysis is
(1) A method in which polyarylene having the sulfonic acid ester group is added to an excess amount of water or alcohol containing a small amount of hydrochloric acid and stirred for 5 minutes or longer. (2) The sulfonic acid ester group is contained in trifluoroacetic acid. Method of reacting polyarylene for about 5 to 10 hours at a temperature of about 80 to 120 ° C. (3) 1 to 1 mol of sulfonic acid ester group (—SO ₃ R ^b ) in polyarylene having a sulfonic acid ester group Examples include a method of reacting the polyarylene in a solution containing 3 moles of lithium bromide, such as N-methylpyrrolidone, at a temperature of about 80 to 150 ° C. for about 3 to 10 hours, and then adding hydrochloric acid. be able to.

  A polyarylene having a sulfonic acid group, a monomer having a skeleton similar to the sulfonic acid ester represented by the general formula (5) and having no sulfonic acid ester group, and an oligomer represented by the general formula (6) In the case where a polyarylene having no sulfonic acid group is synthesized in advance by copolymerization and the polyarylene having no sulfonic acid group is synthesized by sulfonation, the sulfonic acid group is synthesized by a method according to the above synthesis method. After producing a polyarylene having no sulfonic acid, a polyarylene having a sulfonic acid group can be obtained by introducing a sulfonic acid group into the polyarylene having no sulfonic acid group using a sulfonating agent.

  The sulfonation of polyarylene having no sulfonic acid group is carried out by introducing a sulfonic acid group into the polyarylene having no sulfonic acid group by a conventional method using a sulfonating agent in the absence of a solvent or in the presence of a solvent. Can be done.

  As a method for introducing a sulfonic acid group, for example, the polyarylene having no sulfonic acid group is known by using a known sulfonating agent such as sulfuric anhydride, fuming sulfuric acid, chlorosulfonic acid, sulfuric acid, sodium hydrogen sulfite and the like. [Polymer Preprints, Japan, Vol. 42, No. 3, p. 730 (1993); Polymer Preprints, Japan, Vol. 43, No. 3, p. 736 (1994); Polymer Preprints, Japan, Vol. 42, No. 7, p. 2490-2492 (1993)].

  That is, as the reaction conditions for the sulfonation, the polyarylene having no sulfonic acid group is reacted with the sulfonating agent in the absence of a solvent or in the presence of a solvent. Examples of the solvent include hydrocarbon solvents such as n-hexane, ether solvents such as tetrahydrofuran and dioxane, aprotic polar solvents such as dimethylacetamide, dimethylformamide, and dimethylsulfoxide, tetrachloroethane, dichloroethane, chloroform, and chloride. And halogenated hydrocarbons such as methylene. The reaction temperature is not particularly limited, but is usually −50 to 200 ° C., preferably −10 to 100 ° C. Moreover, reaction time is 0.5 to 1,000 hours normally, Preferably it is 1 to 200 hours.

  The amount of sulfonic acid group in the polyarylene having a sulfonic acid group (b) produced by the method as described above is usually 0.3 to 5 meq / g, preferably 0.5 to 3 meq / g, more preferably 0.8 to 2.8 meq / g. If it is less than 0.3 meq / g, the proton conductivity is low and not practical. On the other hand, if it exceeds 5 meq / g, the water resistance may be significantly lowered, which is not preferable.

  The amount of the sulfonic acid group can be adjusted, for example, by changing the type, use ratio, and combination of the monomer (5) and the oligomer (6).

  The molecular weight of the polyarylene having a sulfonic acid group thus obtained is 10,000 to 1,000,000, preferably 20,000 to 800,000 in terms of polystyrene-equivalent weight average molecular weight by gel permeation chromatography (GPC). If it is less than 10,000, the coating film property may be insufficient, such as cracking in the molded film, and there may be a problem in strength properties. On the other hand, if it exceeds 1,000,000, the solubility may be insufficient, and problems such as high solution viscosity and poor processability may occur.

  The polyarylene having a sulfonic acid group may contain an anti-aging agent, preferably a hindered phenol compound having a molecular weight of 500 or more. By containing the anti-aging agent, the durability as an electrolyte is further increased. Can be improved.

Examples of hindered phenol compounds that can be used in the present invention include triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) proonate] (trade name: IRGANOX 245), 1,6-hexanediol-bis [3- (3,5-
Di-t-butyl-4-hydroxyphenyl) propionate] (trade name: IRGANOX 259)
2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -3,5-triazine (trade name: IRGANOX 565), pentaerythrityl-tetrakis [ 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (trade name: IRGANOX 1010), 2,2-thio-diethylenebis [3- (3,5-di-t-butyl- 4-
Hydroxyphenyl) propionate] (trade name: IRGANOX 1035), octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) (trade name: IRGANOX 1076), N, N-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamamide) (trade name: IRGAONOX 1098), 1,3,5-trimethyl-2,4,6-tris (
3,5-di-tert-butyl-4-hydroxybenzyl) benzene (trade name: IRGANOX 1330)
Tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate (
Product name: IRGANOX 3114), 3,9-bis [2- [3- (3-tert-butyl-4-hydroxy-
5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane (trade name: Sumilizer GA-80).

  In the present invention, the hindered phenol compound is preferably used in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the polyarylene having a sulfonic acid group.

  The proportion of the (a) tetrafluoroethylene copolymer having proton conductivity in the polymer composition of the present invention is 5 to 5 when the total of the component (a) and the component (b) is 100% by weight. 90% by weight, preferably 5 to 75% by weight [(b) polyarylene having a sulfonic acid group is 95 to 10% by weight, preferably 95 to 25% by weight]. When the component (a) is less than 5% by weight (when the component (b) exceeds 95% by weight), the toughness of the composite film obtained from this polymer composition may not be sufficient. When the amount exceeds (when the component (b) is less than 5% by weight), the composite film obtained from this polymer composition may be inferior in strength, moisture resistance, gas barrier property, and the like when wet.

  The polymer composition of the present invention contains the above components (a) and (b) as main components, but in addition, additives can be added as necessary. Examples of the additive include a leveling agent and a silane coupling agent.

[Polymer solution composition]
The polymer solution composition of the present invention contains (a) a tetrafluoroethylene copolymer having proton conductivity, (b) a sulfonated polyarylene, and (c) an organic solvent as main components. The polymer solution composition of the present invention is preferably a homogeneous solution.

  The (a) proton conductive tetrafluoroethylene copolymer and (b) sulfonated polyarylene used in the polymer solution composition of the present invention are used in the polymer composition described above. (A) Proton conductivity It is the same as the tetrafluoroethylene copolymer having the formula (b) and the sulfonated polyarylene.

(C) an organic solvent;
(C) As the organic solvent, it is desirable to use a common solvent for the components (a) and (b). Examples of such a common solvent include N-methyl-2-pyrrolidone, methanol, tetrahydrofuran, cyclohexanone, dimethyl sulfoxide, N, N-dimethylformamide, N, N-dimethylacetamide, γ-butyrolactone, ethylene glycol monomethyl ether, Ethylene glycol dimethyl ether, ethylene glycol methyl ethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene Glycol glycol ether acetate, propylene glycol ethyl ether acetate, toluene, xylene, methyl amyl ketone, 4-hydroxy-4-methyl-2-pentanone, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, Ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-2-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, Examples thereof include ethyl 3-methoxypropionate, methyl lactate, ethyl lactate, chloroform, methylene chloride and the like. These can be used alone or as a mixed solvent in which two or more kinds are mixed.

Among these, N-methyl-2-pyrrolidone, methanol, N, N-dimethylformamide, ethyl carbitol, and methyl carbitol are preferable.

  The proportion of the (a) tetrafluoroethylene copolymer having proton conductivity in the polymer solution composition of the present invention is 5 when the total of the component (a) and the component (b) is 100% by weight. -90 wt%, preferably 5-75 wt% [(b) polyarylene having a sulfonic acid group is 95-10 wt%, preferably 95-25 wt%]. When the component (a) is less than 5% by weight (when the component (b) exceeds 95% by weight), the toughness of the composite film obtained from this polymer solution composition may not be sufficient. % (When component (b) is less than 5% by weight), the composite membrane obtained from this polymer solution composition may be inferior in strength, moisture resistance, creep resistance, gas barrier properties, etc. .

  Further, the solid content concentration in the polymer solution composition of the present invention, that is, the ratio of the component (a) and the component (b) is 3 to 40% by weight, preferably 5 to 35% in the polymer solution composition. % By weight. If it is less than 3% by weight, a coating film having a sufficient thickness may not be obtained. On the other hand, if it exceeds 40% by weight, it may not be sufficiently cast and a uniform coating film may not be obtained.

  The polymer solution composition of the present invention contains the above components (a) and (b) as main components, but in addition, additives may be added as necessary. Examples of the additive include a leveling agent and a silane coupling agent.

[Manufacture of composite membranes]
In order to produce a composite membrane (proton conducting membrane) excellent in proton conductivity using the polymer composition of the present invention, for example, a method of producing a film by extrusion after melting the polymer composition, etc. Can be used.

  In order to produce a composite membrane (proton conducting membrane) excellent in proton conductivity using the polymer solution composition of the present invention, a casting method in which the composition is formed into a film by casting on a substrate, for example. A general method can be used.

Substrates used in the casting method include polyethylene terephthalate (PET) film, polybutylene terephthalate (PBT) film, nylon 6 film, nylon 6,6 film, polypropylene film, plastic film such as polycarbonate film, glass plate, etc. Preferably, a PET film or a glass plate is used.

  The thickness of the plastic film (plate) serving as the substrate is usually 50 to 250 μm, preferably 75 to 200 μm. Moreover, in a glass plate, it is 1-5 mm in thickness.

  After film formation by the casting method, the composite film of the present invention is obtained by heating and drying at room temperature to 200 ° C., preferably 50 to 150 ° C., for 5 to 180 minutes, preferably 5 to 120 minutes. Drying can be performed under conditions of normal pressure to vacuum. Further, the heating may be performed by sequentially raising the temperature.

In the present invention, it is also a preferred means that the composite film is subjected to a curing treatment by irradiating it with an electron beam during the composite film forming step or to the obtained composite film.
In the present invention, the method of irradiating the composite film formed on the substrate or the obtained composite film with an electron beam is not particularly limited, but for example, it is preferably performed under the following conditions.
(1) Atmosphere: Nitrogen, argon or vacuum (among them, nitrogen is more preferred)
(2) Temperature: 20 to 450 ° C. (The glass transition temperature of the irradiated polymer is more preferable from room temperature)
(3) Electron dose: 5 to 200 Mrad (10 to 150 Mrad is more preferable)
When electron beam irradiation is performed in an atmosphere of nitrogen, argon, or vacuum, the composite film is not oxidized, and sufficient heat resistance and durability can be obtained.
The temperature is not particularly limited as long as it is 20 to 450 ° C., but can be cured more efficiently if it is carried out at a glass transition temperature of the polymer to be irradiated or a temperature several tens of degrees higher than this.
When the electron dose is in the range of 5 to 200 Mrad, the curing reaction can proceed without causing decomposition of the sulfonated product of polyarylene. If it is less than 5 Mrad, the irradiation energy required for crosslinking cannot be obtained. On the other hand, if it exceeds 200 Mrad, a part of the polymer is decomposed, which is not preferable.

  The dry film thickness of the composite membrane (proton conductive membrane) obtained from the polymer composition or polymer solution composition of the present invention is usually 10 to 150 μm, preferably 20 to 80 μm.

  The composite membrane (proton conductive membrane) obtained from the polymer composition or polymer solution composition of the present invention is composed only of polyarylene having a sulfonic acid group while maintaining gas barrier properties without impairing proton conductivity. Strength properties and toughness are improved compared to the resulting film. In particular, the composite membrane (proton conductive membrane) obtained from the polymer solution composition comprises an elastomeric (a) tetrafluoroethylene copolymer having proton conductivity and a resinous (b) polysulfonic acid group-containing poly (ethylene) copolymer. Since the arylene is combined through solution homogenization, the above effect is particularly excellent.

  Therefore, the composite membrane of the present invention can be used for, for example, an electrolyte for a primary battery, an electrolyte for a secondary battery, a solid polymer electrolyte for a fuel cell, a display element, various sensors, a signal transmission medium, a solid capacitor, an ion exchange membrane, and the like. It can be used for a proton-conducting conductive membrane.

[Example]
EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples.
In the examples, various measurement items were determined as follows.

[Measurement of molecular weight]
As for the weight average molecular weight of polyarylene having no sulfonic acid group, the molecular weight in terms of polystyrene was determined by GPC using tetrahydrofuran (THF) as a solvent. The molecular weight of the polyarylene having a sulfonic acid group was determined by GPC using N-methyl-2-pyrrolidone (NMP) to which lithium bromide and phosphoric acid were added as a solvent as an eluent.

[Sulfonic acid equivalent]
The obtained polyarylene having a sulfonic acid group is washed until the washing water becomes neutral, thoroughly washed with water except for free remaining acid, dried, weighed in a predetermined amount, and THF / water. Titration was performed using a standard solution of NaOH using phenolphthalein dissolved in a mixed solvent as an indicator, and the sulfonic acid equivalent was determined from the neutralization point.

[Tensile strength]
The tensile strength was measured by a tensile test at room temperature of the obtained film.

[Elastic modulus]
The elastic modulus was calculated from the initial slope of the stress-strain curve of the resulting film at room temperature tensile test.

[Film resistance]
Using a folding tester, the measurement was performed under the conditions of a bending frequency of 166 times / minute, a load of 200 g, and a bending deformation angle of 135 °.

[Water absorption rate]
The film was immersed in distilled water at room temperature for 1 hour and determined from the weight change before and after.

[Proton conductivity]
A film sample having a diameter of 13 mm placed under 100% relative humidity is sandwiched between platinum electrodes, sealed in a sealed cell, and using an impedance analyzer (HYP4192A), a frequency of 5 to 13 MHz, an applied voltage of 12 mV, a temperature of 20 ° C., The absolute value and phase angle of the cell impedance were measured at 50 ° C. and 100 ° C. The obtained data was measured for complex impedance using a computer at an oscillation level of 12 mV, and proton conductivity was calculated.

[Gas permeability]
Using a high vacuum method gas permeation tester, the gas permeation amount at 30 ° C. was determined and normalized to unit time, film thickness, pressure, and area.

[(A) component]
As the component (a), a commercially available perfluoroalkylsulfonic acid (manufactured by DuPont, trade name: Nafion), a solution consisting of a 5% by weight lower aliphatic alcohol / water (80/20 weight ratio) solution [Aldrich ( Aldrich)] was used.

[Component (b)]
The polyarylene copolymer having a sulfonic acid group used as the component (b) was synthesized by the following method.

[Preparation of oligomer]
2,2-bis (4-hydroxyphenyl) -1,1,1,3 was added to a 1 L three-necked flask equipped with a stirrer, thermometer, cooling tube, Dean-Stark tube, and three-way cock for introducing nitrogen. , 3,3-hexafluoropropane (bisphenol AF) 67.3 g (0.20 mol), 4,4′-dichlorobenzophenone (4,4′-DCBP) 60.3 g (0.24 mol), potassium carbonate
71.9 g (0.52 mol), N, N-dimethylacetamide (DMAc) 300 mL,
150 mL of toluene was taken and heated in an oil bath under a nitrogen atmosphere and reacted at 130 ° C. with stirring. When water produced by the reaction was azeotroped with toluene and reacted while being removed from the system with a Dean-Stark tube, almost no water was produced in about 3 hours. The reaction temperature was gradually increased from 130 ° C to 150 ° C. Most of the toluene was removed while gradually raising the reaction temperature to 150 ° C., and the reaction was continued at 150 ° C. for 10 hours, and then 10.0 g of 4,4′-DCBP (
0.040 mol) was added, and the reaction was further continued for 5 hours. The resulting reaction solution was allowed to cool, and then the by-product inorganic compound precipitate was removed by filtration, and the filtrate was put into 4 L of methanol. The precipitated product was separated by filtration, collected, dried, and dissolved in 300 mL of tetrahydrofuran. This was reprecipitated in 4 L of methanol to obtain 95 g (yield 85%) of the target compound.

The weight average molecular weight in terms of polystyrene determined by GPC (THF solvent) of the obtained polymer was 11,200. Further, the obtained polymer was soluble in THF, NMP, DMAc, sulfolane and the like, Tg was 110 ° C., and thermal decomposition temperature was 498 ° C.
The obtained compound was an oligomer represented by the following formula (I) (hereinafter referred to as “BCPAF oligomer”).

[Preparation of Polyarylene Copolymer with Neopentyl Group as Protecting Group (PolyAB-SO ₃ neo-Pe)]
4- [4- (2,5-dichlorobenzoyl) phenoxy] benzenesulfonic acid neo was added to a 1 L three-necked flask equipped with a stirrer, thermometer, condenser, Dean-Stark tube, and three-way cock for introducing nitrogen. -Pentyl (A-SO ₃ neo-Pe) 39.58 g (98.64 mmol), BCPAF oligomer (Mn = 11200) 15.23 g (1.36 mmol), Ni (PPh ₃ ) ₂ Cl ₂ 1.67 g ( 2.55 mmol), 10.49 g (40 mmol) of PPh ₃ , 0.45 g (3 mmol) of NaI, 15.69 g (240 mmol) of zinc dust, and 390 mL of dry NMP were added under nitrogen. The reaction system was heated with stirring (finally heated to 75 ° C.) and allowed to react for 3 hours. The polymerization reaction solution was diluted with 250 mL of THF, stirred for 30 minutes,
Use Celite as a filter aid, pour the filter paper and filtrate into 1500 mL of excess methanol,
Solidified. The coagulum was collected by filtration, air-dried, redissolved in THF / NMP (200/300 mL each), and coagulated with 1500 mL of a large excess of methanol. After air drying, 47.0 g (yield 99%) of a copolymer (PolyAB-SO ₃ neo-Pe) composed of a sulfonic acid derivative protected with a target yellow fibrous neopentyl group was obtained by heat drying. The molecular weight by GPC was Mn = 47,600 and Mw = 159,000.

[Preparation of polyarylene copolymer (II) having a sulfonic acid group]
Thus obtained 5.1 g of PolyAB-SO ₃ neo-Pe was dissolved in 60 mL of NMP and heated to 90 ° C. To the reaction system, a mixture of 50 mL of methanol and 8 mL of concentrated hydrochloric acid was added at a time. While in suspension, the reaction was allowed to proceed for 10 hours under mild reflux conditions. A distillation apparatus was installed, and excess methanol was distilled off to obtain a light green transparent solution. This solution was poured into a large amount of water / methanol (1: 1 weight ratio) to solidify the polymer, and then the polymer was washed with ion exchange water until the pH of the washing water was 6 or more. From the IR spectrum of the polymer thus obtained and the quantitative analysis of the ion exchange capacity, it was found that the sulfonic acid ester group (—SO ₃ R ^a ) was quantitatively converted to the sulfonic acid group (—SO ₃ H). .

  The obtained polyarylene copolymer (II) having a sulfonic acid group had molecular weights by GPC of Mn = 53,200 and Mw = 185,000, and the sulfonic acid equivalent was 1.9 meq / g.

A 10% by weight methanol / water (80/20 weight ratio) solution of the polyarylene copolymer (II) having a sulfonic acid group thus obtained was used as the component (b).
The solution of the component (a) and the solution of the component (b) are blended so as to have a weight ratio of 25/75 in terms of solid content, and this solution is stirred at room temperature and mixed to obtain a uniform solution. Prepared. The resulting solution was a pale yellow transparent solution. At this time, the solid content concentration of the homogeneous solution was 8% by weight.

  The obtained solution composition was cast on a glass substrate using a doctor blade, dried at 80 ° C. for 15 minutes, 100 ° C. for 15 minutes, 150 ° C. for 30 minutes, and 180 ° C. for 30 minutes to obtain a film thickness. A flexible composite film of 30 μm was obtained. The evaluation results of the obtained composite membrane are shown in Table 1.

Example 1 except that polyarylene (III) having a sulfonic acid group synthesized by the following method was used in place of the polyarylene copolymer (II) having a sulfonic acid group in Example 1. A composite membrane was obtained in the same manner.

[Synthesis of polyarylene copolymer]
28.1 g (2.5 mmol) of the oligomer of formula (I) obtained in Example 1 above, 2,5-dichloro-4 ′-(4-phenoxy) phenoxybenzophenone (DCPPB) 35.
9 g (82.5 mmol), bis (triphenylphosphine) nickel dichloride
67 g (2.6 mmol), 1.66 g (11.1 mmol) of sodium iodide, 8.92 g (34.0 mmol) of triphenylphosphine, and 13.3 g (204 mmol) of zinc dust were placed in a flask and purged with dry nitrogen. 160 ml of N-methyl-2-pyrrolidone was added, and the mixture was heated to 80 ° C. and stirred for 4 hours to carry out polymerization. The polymerization solution is diluted with THF, coagulated and recovered with hydrochloric acid / methanol, repeatedly washed with methanol, dissolved in THF, purified by reprecipitation into methanol, and the collected polymer is vacuum-dried to obtain 51.0 g of the desired copolymer. (90%) was obtained. The number-average molecular weight in terms of polystyrene determined by GPC (THF) is 38,900,
The weight average molecular weight was 160,000.

[Synthesis of polyarylene (III) having a sulfonic acid group]
50 g of the copolymer was placed in a 1000 ml separable flask equipped with a stirrer and a thermometer, 500 ml of sulfuric acid having a concentration of 98% was added, and the mixture was stirred for 24 hours under a nitrogen stream while maintaining the internal temperature at 25 ° C. The obtained solution was poured into a large amount of ion exchange water to precipitate a polymer. The washing of the polymer was repeated until the washing water had a pH of 5. By drying, a polymer having 56 g (95%) of a sulfonic acid group was obtained. The number average molecular weight in terms of polystyrene determined by GPC (NMP) of the polymer having a sulfonic acid group was 45,500, and the weight average molecular weight was 176,000. The sulfonic acid equivalent of the polymer having this sulfonic acid group was 2.1 meq / g.
The evaluation results of the obtained composite membrane are shown in Table 1.

[Comparative Example 1]
A 10% by weight methanol / water (80/20 weight ratio) solution of the polyarylene copolymer (II) having a sulfonic acid group used in Example 1 was cast on a glass substrate using a doctor blade, and 80% Drying was performed at 15 ° C. for 15 minutes, 100 ° C. for 15 minutes, 150 ° C. for 30 minutes, and 180 ° C. for 30 minutes to obtain a film having a thickness of 30 μm. Table 1 shows the evaluation results of the obtained film.

[Comparative Example 2]
10% by weight of the polyarylene copolymer (III) having a sulfonic acid group used in Example 2
A methanol / water (80/20 weight ratio) solution is cast on a glass substrate using a doctor blade and dried at 80 ° C. for 15 minutes, 100 ° C. for 15 minutes, 150 ° C. for 30 minutes, and 180 ° C. for 30 minutes. As a result, a film having a thickness of 30 μm was obtained. Table 1 shows the evaluation results of the obtained film.

[Comparative Example 3]
Table 1 shows the evaluation results of the commercially available perfluoroalkylsulfonic acid membrane used in Example 1 (manufactured by DuPont, Nafion ™ 112, film thickness 50 μm).

Claims (12)

A polymer comprising (a) a tetrafluoroethylene copolymer having proton conductivity, and (b) a polyarylene having a sulfonic acid group having a repeating unit represented by the following general formula (2): Composition;

(In the formula, A represents a divalent electron-withdrawing group, B represents a divalent electron-donating group or a direct bond, Ar represents an aromatic group having a substituent represented by —SO ₃ H, m represents an integer of 0 to 10, n represents an integer of 0 to 10, and k represents an integer of 1 to 4. The polymer composition according to claim 1, wherein the tetrafluoroethylene copolymer (a) having proton conductivity comprises a structural unit represented by the following general formula (1);

(Wherein x is a number from 1 to 30, y is a number from 10 to 2,000, m is a number from 0 to 10, and n is from 1 to 1
The number 0, A represents —SO ₃ Z or —COOZ (where Z is a hydrogen atom or an alkali metal atom). ) The polyarylene having the sulfonic acid group (b) has a repeating unit represented by the following general formula (3) in addition to the repeating unit represented by the general formula (2). The polymer composition according to 1 or 2;

(Wherein R ^{1 to} R ⁸ may be the same or different from each other, and at least one selected from the group consisting of a hydrogen atom, a fluorine atom, an alkyl group, a fluorine-substituted alkyl group, an allyl group, an aryl group, and a cyano group) W represents a divalent electron-withdrawing group or a single bond, T represents a single bond or a divalent organic group, and p represents an integer of 2 or more when T is —O—. In the case other than -O-, an integer of 1 or more is shown.)   When the total of (a) the tetrafluoroethylene copolymer having proton conductivity and (b) the sulfonic acid group-containing polyarylene having the repeating unit represented by the general formula (2) is 100% by weight The polymer composition according to any one of claims 1 to 3, comprising 5 to 90% by weight of the component (a) and 95 to 10% by weight of the component (b).   A composite film obtained from the polymer composition according to any one of claims 1 to 4.   The composite membrane according to claim 5, which is a proton conducting membrane. (A) a tetrafluoroethylene copolymer having proton conductivity,
(B) a polymer solution composition comprising polyarylene having a sulfonic acid group having a repeating unit represented by the following general formula (2), and (c) an organic solvent;

(In the formula, A represents a divalent electron-withdrawing group, B represents a divalent electron-donating group or a direct bond, Ar represents an aromatic group having a substituent represented by —SO ₃ H, m represents an integer of 0 to 10, n represents an integer of 0 to 10, and k represents an integer of 1 to 4. The polymer solution composition according to claim 7, wherein the (a) tetrafluoroethylene copolymer having proton conductivity comprises a structural unit represented by the following general formula (1):

(Wherein x is a number from 1 to 30, y is a number from 10 to 2,000, m is a number from 0 to 10, and n is from 1 to 1
The number 0, A represents —SO ₃ Z or —COOZ (where Z is a hydrogen atom or an alkali metal atom). ) The polyarylene having the sulfonic acid group (b) has a repeating unit represented by the following general formula (3) in addition to the repeating unit represented by the general formula (2). A polymer solution composition according to 7 or 8;

(Wherein R ^{1 to} R ⁸ may be the same or different from each other, and at least one selected from the group consisting of a hydrogen atom, a fluorine atom, an alkyl group, a fluorine-substituted alkyl group, an allyl group, an aryl group, and a cyano group) W represents a divalent electron-withdrawing group or a single bond, T represents a single bond or a divalent organic group, and p represents an integer of 2 or more when T is —O—. In the case other than -O-, an integer of 1 or more is shown.)   When the total of (a) the tetrafluoroethylene copolymer having proton conductivity and (b) the sulfonic acid group-containing polyarylene having the repeating unit represented by the general formula (2) is 100% by weight The polymer solution composition according to any one of claims 7 to 9, comprising 5 to 90% by weight of the component (a) and 95 to 10% by weight of the component (b).   A composite film obtained by applying the polymer solution composition according to any one of claims 7 to 10 to a substrate and drying it.   The composite membrane according to claim 11, which is a proton conducting membrane.