JP4763754B2 - Solid polymer electrolyte membrane, raw material monomer composition and fuel cell - Google Patents

Description

  The present invention relates to a solid polymer electrolyte membrane exhibiting high proton conductivity over a wide temperature range and excellent in solvent resistance, a raw material monomer composition thereof, and a fuel cell using the solid polymer electrolyte membrane.

  As a solid polymer electrolyte membrane, a fluorine-based polymer electrolyte membrane having a sulfonic acid group in a side chain of a perfluoro skeleton known by a trademark of Nafion (manufactured by DuPont) has been put into practical use. This electrolyte membrane is excellent in heat resistance and chemical resistance and can withstand use under severe conditions, but has a problem that it is very expensive.

  Therefore, JP-A-2003-86021 discloses a phosphate group-containing unsaturated monomer having a phosphate group and an ethylenically unsaturated bond in the molecule, and a sulfonic acid having a sulfonate group and an ethylenically unsaturated bond in the molecule. A solid polymer electrolyte membrane composed of a copolymer with a group-containing unsaturated monomer has been proposed. This solid polymer electrolyte membrane can be manufactured not only at a relatively low cost, but also has a high conductivity, a low temperature dependency of conductivity, and excellent heat resistance and solvent resistance. It was in line with the molecular electrolyte membrane.

（但しR³¹は４価の芳香族基であり、R³²は脂肪族基、脂環族基又は芳香族基であり、R³³及びR³⁴はそれぞれ独立に水素原子又は炭素数２〜５のアルキルリン酸基であり、かつ繰り返し構造単位中に0.1〜２個のアルキルリン酸基を含み、kは10〜10,000である。）により表されるポリベンズイミダゾールのアルキルリン酸塩からなる高分子固体電解質を提案している。 However, solid polymer electrolyte membranes for fuel cells are required to further improve not only conductivity but also solvent resistance and durability. Under such circumstances, Japanese Patent Application Laid-Open No. 2003-22823 (Patent Document 1) describes a part of a side chain phosphate group, phosphonic acid group or phosphinic acid group as a proton conductive membrane having durability and mechanical strength. Proton-conducting membranes are proposed in which an amine-salt polymer is supported in the pores of a porous membrane. JP-A-910982 (Patent Document 2) discloses the following general formula (28) as a polymer solid electrolyte having proton conductivity over a wide temperature range:

(However, R ³¹ is a tetravalent aromatic group, R ³² is an aliphatic group, an alicyclic group or an aromatic group, and R ³³ and R ³⁴ are each independently a hydrogen atom or a C 2-5 carbon atom. A polymer comprising an alkyl phosphate of polybenzimidazole represented by the formula (1): an alkyl phosphate group and 0.1 to 2 alkyl phosphate groups in a repeating structural unit, and k is 10 to 10,000. A solid electrolyte is proposed.

However, in Patent Document 1, since an alkanolamine having no unsaturated group is used as the amine for converting the phosphate group into an amine, the amino group and the phosphate group only form a quaternary ammonium base. Yes, a crosslinked structure could not be formed unless another crosslinkable unsaturated monomer was added. Since the polymer solid electrolyte of Patent Document 2 is produced by introducing an alkyl phosphate group into polybenzimidazole, the amount of phosphate group that can be introduced is about 70% of the theoretical value. There was a limit to the improvement in density. For this reason, the proton conductivity of the polymer solid electrolyte disclosed in Patent Document 2 is in the order of 10 ⁻⁴ S · cm ⁻¹ even under conditions of relative humidity of 100% / temperature of 100 ° C. and cannot be said to be necessarily excellent. .

JP2003-22823 JP-A-910982

  Accordingly, an object of the present invention is to use an inexpensive solid polymer electrolyte membrane having high proton conductivity in a wide temperature range and having excellent solvent resistance, a raw material monomer composition thereof, and a solid polymer electrolyte membrane. Is to provide a fuel cell.

  As a result of diligent research in view of the above object, the present inventors have found that (A) a phosphate group-containing unsaturated monomer (a) having a phosphate group and an ethylenically unsaturated bond in the molecule, and substitution in the molecule. Or an amino group-containing unsaturated monomer (b) having an unsubstituted amino group and an ethylenically unsaturated bond, and (a) containing a quaternary ammonium salt modified with (b). When the monomer composition and (B) the fluorine-containing unsaturated monomer (c) are copolymerized, a low-cost solid having high proton conductivity in a wide temperature range and excellent solvent resistance is obtained. The inventors have discovered that a molecular electrolyte membrane can be obtained and have arrived at the present invention.

（ただしR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、nは１〜６の整数である）により表され、
(b)は下記一般式(2)：

（ただしR₃は水素基又はメチル基であり、R₄及びR₅はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、X₁は−O−基又は−NH−基であり、Y₁は置換もしくは無置換の炭素数１〜６のアルキレン基又は置換もしくは無置換の炭素数６〜16のアリーレン基である）により表される化合物、下記一般式(3)：

（ただしR₆は水素基又はメチル基であり、R₇及びR₈はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基である）により表される化合物、下記一般式(4)：

（ただしR₉は水素基又はメチル基であり、R₁₀及びR₁₁はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、Y₂は置換もしくは無置換の炭素数１〜６のアルキレン基又は置換もしくは無置換の炭素数６〜16のアリーレン基である）により表される化合物、下記一般式(5)：

（ただしR₁₂は水素基又はメチル基であり、R₁₃及びR₁₄はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基である）により表される化合物、下記一般式(6)：

（ただしR₁₅及びR₁₆はそれぞれ独立に水素基又はメチル基であり、R₁₇は水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、Y₃及びY₄はそれぞれ独立に置換もしくは無置換の炭素数１〜６のアルキレン基又は置換もしくは無置換の炭素数６〜16のアリーレン基である）により表される化合物、及び１個以上のビニル基を有するヘテロ環状アミン化合物からなる群から選ばれた少なくとも一種であり、
(c)は、(i) 少なくとも１個のフッ素基を有する（メタ）アクリル酸エステル類、(ii) 少なくとも１個のフッ素基を有する（メタ）アクリル酸類、(iii) 少なくとも１個のフッ素基を有するアルキル基及び／又は少なくとも１個のフッ素基と１個のエチレン性不飽和結合とを有するオレフィン系不飽和単量体、並びに(iv) 少なくとも１個のフッ素基を含有するアルキレン基と２個のエチレン性不飽和結合とを有するジエン系不飽和単量体からなる群から選ばれた少なくとも一種であることを特徴とする。 That is, the solid polymer electrolyte membrane of the present invention comprises (A) a phosphate group-containing unsaturated monomer (a) having a phosphate group and an ethylenically unsaturated bond, a substituted or unsubstituted amino group, and an ethylenic group. An amino group-containing unsaturated monomer having an unsaturated bond (b) is reacted in a range where the ratio of the amino group of (b) to the phosphate group of (a) is 50 to 180 mol%, a monomer composition comprising a quaternary ammonium salt wherein (a) is modified in (b);
(B) at least copolymerized with a fluorine group-containing unsaturated monomer (c),
(a) is the following general formula (1):

(Wherein R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, and n is an integer of 1 to 6),
(b) is the following general formula (2):

(However, R ₃ is a hydrogen group or a methyl group, R ₄ and R ₅ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and X ₁ is —O -Group or -NH- group, and Y ₁ is a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted arylene group having 6 to 16 carbon atoms), General formula (3):

Wherein R ₆ is a hydrogen group or a methyl group, and R ₇ and R ₈ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms. The following general formula (4):

(Wherein R ₉ is a hydrogen group or a methyl group, R ₁₀ and R ₁₁ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, and Y ₂ is substituted or An unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted arylene group having 6 to 16 carbon atoms), the following general formula (5):

Wherein R ₁₂ is a hydrogen group or a methyl group, and R ₁₃ and R ₁₄ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms. The following general formula (6):

(However, R ₁₅ and R ₁₆ are each independently a hydrogen group or a methyl group, R ₁₇ is a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and Y ₃ and Y ₄ Are each independently a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted arylene group having 6 to 16 carbon atoms, and a hetero compound having one or more vinyl groups. Is at least one selected from the group consisting of cyclic amine compounds,
(c) is (i) (meth) acrylic acid ester having at least one fluorine group, (ii) (meth) acrylic acid having at least one fluorine group, (iii) at least one fluorine group And / or an olefinically unsaturated monomer having at least one fluorine group and one ethylenically unsaturated bond, and (iv) an alkylene group containing at least one fluorine group and 2 It is at least one selected from the group consisting of diene unsaturated monomers having one ethylenically unsaturated bond.

R _{1 in} (a) is preferably H or CH ₃ , and R ₂ is preferably H, CH ₃ or CH ₂ Cl.

（ただしX₃は水素基、フッ素基、少なくとも１個のフッ素基を有する又は有しないメチル基であり、R₂₅は少なくとも１個のフッ素基を有する又は有しないアルキル基である。）により表される化合物が好ましく、2，2，2−トリフルオロエチルメタクリートがより好ましい。前記フッ素基含有（メタ）アクリル酸類としては下記一般式(8)：

（ただしX₄はフッ素基又は少なくとも１個のフッ素基を有するメチル基である。）により表される化合物が好ましい。前記フッ素基含有オレフィン系不飽和単量体としては
下記一般式(9)：

（ただしRf₁は少なくとも１個のフッ素基を含有するアルキル基であり、X₅、X₆及びX₇はそれぞれ独立に水素基又はフッ素基である。）又は下記一般式(10)：

（ただしX₈、X₉及びX₁₀はそれぞれ独立にフッ素基又は少なくとも１個のフッ素基を有するメチル基であり、X₁₁はフッ素基、その他のハロゲン、少なくとも１個のフッ素基を有するフッ素基含有メチル基、アルコキシ基、フッ素基含有アルコキシ基、アルキル基又は水素基である。）により表される化合物が好ましい。前記フッ素基含有ジエン系不飽和単量体としては下記一般式(11)：

（ただしRf₂は少なくとも１個のフッ素基を含有するアルキレン基であり、X₁₂、X₁₃、X₁₄、X₁₅、X₁₆及びX₁₇はそれぞれ独立に水素基又はフッ素基である。）により表される化合物が好ましい。 Examples of the fluorine group-containing (meth) acrylic acid esters include the following general formula (7):

(Wherein X ₃ is a hydrogen group, a fluorine group, a methyl group having or not having at least one fluorine group, and R ₂₅ is an alkyl group having or not having at least one fluorine group). Are preferred, and 2,2,2-trifluoroethyl methacrylate is more preferred. The fluorine group-containing (meth) acrylic acids include the following general formula (8):

A compound represented by the formula (wherein X ₄ is a fluorine group or a methyl group having at least one fluorine group) is preferred. The fluorine group-containing olefinically unsaturated monomer is represented by the following general formula (9):

(Where Rf ₁ is an alkyl group containing at least one fluorine group, and X ₅ , X ₆ and X ₇ are each independently a hydrogen group or a fluorine group) or the following general formula (10):

(However, X ₈ , X ₉ and X ₁₀ are each independently a fluorine group or a methyl group having at least one fluorine group, and X ₁₁ is a fluorine group, other halogens, or a fluorine group having at least one fluorine group. A methyl group, an alkoxy group, a fluorine group-containing alkoxy group, an alkyl group or a hydrogen group). The fluorine group-containing diene unsaturated monomer is represented by the following general formula (11):

(Wherein Rf ₂ is an alkylene group containing at least one fluorine group, and X ₁₂ , X ₁₃ , X ₁₄ , X ₁₅ , X ₁₆ and X ₁₇ are each independently a hydrogen group or a fluorine group). The compounds represented are preferred.

  In a preferred example of the solid polymer electrolyte membrane, an unsaturated monomer (d) other than (a) to (c) is included as a copolymerization component, and (d) is one or more ethylenically unsaturated bonds in the molecule. One of unsaturated monomer (d-1) having a functional group and one or more unsaturated monomer (d-2) having one or more ethylenically unsaturated bonds in the molecule but having no functional group Or (d-1) has at least one functional group selected from the group consisting of a phosphoric acid residue, a sulfonic acid group, a carboxylic acid group and an alcoholic hydroxyl group, and (d-2) is It is at least one selected from the group consisting of (meth) acrylonitrile, (meth) acrylic acid esters, (meth) acrylic acid amides, substituted or unsubstituted styrenes and vinyls. The weight ratio of (the quaternary ammonium salt-containing monomer composition) / (total of (c) and (d)) is preferably 80/20 to 40/60.

（但しR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、R₃は水素基又はメチル基であり、R₄及びR₅はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、X₁は−O−基又は−NH−基であり、Y₁は置換もしくは無置換の炭素数１〜６のアルキレン基又は炭素数６〜12のアリーレン基であり、nは１〜６の整数である。）により表される化合物、下記一般式(13)：

（但しR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、R₆は水素基又はメチル基であり、R₇及びR₈はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、nは１〜６の整数である。）により表される化合物、下記一般式(14)：

（但しR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、R₉は水素基又はメチル基であり、R₁₀及びR₁₁はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、Y₂は置換もしくは無置換の炭素数１〜６のアルキレン基又は置換もしくは無置換の炭素数６〜16のアリーレン基であり、nは１〜６の整数である。）により表される化合物、下記一般式(15)：

（但しR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、R₁₂は水素基又はメチル基であり、R₁₃及びR₁₄はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、nは１〜６の整数である。）により表される化合物、下記一般式(16)：

（但しR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、R₁₅及びR₁₆はそれぞれ独立に水素基又はメチル基であり、R₁₇は水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、Y₃及びY₄はそれぞれ独立に置換もしくは無置換の炭素数１〜６のアルキレン基又は置換もしくは無置換の炭素数６〜16のアリーレン基であり、nは１〜６の整数である。）により表される化合物、並びに下記一般式(1)：

（ただしR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、nは１〜６の整数である。）により表されるリン酸基含有不飽和単量体を、１個以上のビニル基を有するヘテロ環状アミンで変性した化合物からなる群から選ばれた少なくとも一種であり、
(c)は、(i) 少なくとも１個のフッ素基を有する（メタ）アクリル酸エステル類、(ii) 少なくとも１個のフッ素基を有する（メタ）アクリル酸類、(iii) 少なくとも１個のフッ素基を有するアルキル基及び／又は少なくとも１個のフッ素基と１個のエチレン性不飽和結合とを有するオレフィン系不飽和単量体、並びに(iv) 少なくとも１個のフッ素基を含有するアルキレン基と２個のエチレン性不飽和結合とを有するジエン系不飽和単量体からなる群から選ばれた少なくとも一種であることを特徴とする。 The monomer composition for solid polymer electrolyte of the present invention comprises (A) a phosphate group-containing unsaturated monomer (a) having a phosphate group and an ethylenically unsaturated bond, and a substituted or unsubstituted amino group. And an amino group-containing unsaturated monomer (b) having an ethylenically unsaturated bond are reacted in a range where the ratio of the amino group of (b) to the phosphate group of (a) is 50 to 180 mol%. A monomer composition comprising a quaternary ammonium salt wherein (a) is modified in (b);
(B) at least a fluorine group-containing unsaturated monomer (c),
The quaternary ammonium salt has the following general formula (12):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₃ is a hydrogen group or a methyl group, and R ₄ and R ₅ are each independently hydrogen. Group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, X ₁ is an —O— group or an —NH— group, and Y ₁ is a substituted or unsubstituted carbon atom having 1 to 6 carbon atoms. An alkylene group or an arylene group having 6 to 12 carbon atoms, and n is an integer of 1 to 6.), a compound represented by the following general formula (13):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₆ is a hydrogen group or a methyl group, and R ₇ and R ₈ are each independently hydrogen. A group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, and n is an integer having 1 to 6), the following general formula (14):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₉ is a hydrogen group or a methyl group, and R ₁₀ and R ₁₁ are each independently hydrogen. Group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and Y ₂ is a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted carbon group having 6 to 16 carbon atoms. An arylene group, and n is an integer of 1 to 6.), a compound represented by the following general formula (15):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₁₂ is a hydrogen group or a methyl group, and R ₁₃ and R ₁₄ are each independently hydrogen. A group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, and n is an integer of 1 to 6), the following general formula (16):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₁₅ and R ₁₆ are each independently a hydrogen group or a methyl group, and R ₁₇ is a hydrogen group. Group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, and Y ₃ and Y ₄ are each independently a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted group. A compound having 6 to 16 carbon atoms and n is an integer of 1 to 6), and the following general formula (1):

(Wherein R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, and n is an integer of 1 to 6). The monomer is at least one selected from the group consisting of compounds modified with a heterocyclic amine having one or more vinyl groups,
(c) is (i) (meth) acrylic acid ester having at least one fluorine group, (ii) (meth) acrylic acid having at least one fluorine group, (iii) at least one fluorine group And / or an olefinically unsaturated monomer having at least one fluorine group and one ethylenically unsaturated bond, and (iv) an alkylene group containing at least one fluorine group and 2 It is at least one selected from the group consisting of diene unsaturated monomers having one ethylenically unsaturated bond.

  The monomer composition for a solid polymer electrolyte is an unreacted (a), an unreacted (b), and an unreacted product in which all of the hydroxyl groups in the phosphate group of (a) have reacted with the amino group of (b). It may contain at least one selected from the group consisting of saturated monomers.

  The solid polymer electrolyte membrane of the present invention is suitable for fuel cell applications.

The quaternary ammonium salt constituting the solid polymer electrolyte membrane of the present invention has an ethylenically unsaturated bond derived from a phosphate group-containing unsaturated monomer and an amino group-containing unsaturated monomer in one molecule. The solid polymer electrolyte membrane has a crosslinked structure and has excellent solvent resistance. Furthermore, the solid polymer electrolyte membrane of the present invention has an excellent proton conductivity of 10 ⁻³ to 10 ⁻⁵ S · cm ^{−1 at} a relative humidity of 90% / temperature of 20 to 80 ° C., and the proton conductivity temperature. Small dependency. Therefore, the solid polymer electrolyte membrane of the present invention includes an electrolyte membrane for a primary battery, an electrolyte membrane for a secondary battery, an electrolyte membrane for a fuel cell, a display element membrane, various sensor membranes, a signal transmission medium membrane, a solid capacitor membrane, and an ion exchange membrane. It can utilize suitably for. In particular, it is expected to be applied as a solid polymer electrolyte for DMFC (direct methanol fuel cell) for high power applications.

[1] Monomer composition for solid polymer electrolyte The monomer composition for solid polymer electrolyte of the present invention comprises (A) phosphoric acid having one phosphoric acid group and one ethylenically unsaturated bond in the molecule. A group-containing unsaturated monomer (a) and an amino group-containing unsaturated monomer (b) each having one or more substituted or unsubstituted amino groups and ethylenically unsaturated bonds in the molecule (a) ) In the range in which the ratio of the amino group of (b) to the phosphate group of (b) is 50 to 180 mol%, (a) is modified with (b), and the hydroxyl group in the phosphate group of (a) (B) a monomer composition containing a quaternary ammonium salt reacted with an amino group, and (B) a fluorine group-containing unsaturated monomer (c).

（ただしR₁は水素又はアルキル基であり、R₂は水素又は置換もしくは無置換のアルキル基であり、nは１〜６の整数である。）により表すことができる。R₁はH又はCH₃であるのが好ましく、R₂はH、CH₃又はCH₂Clであるのが好ましい。 (1) Phosphoric acid group-containing unsaturated monomer The phosphoric acid group-containing unsaturated monomer is represented by the following general formula (1):

(Where R ₁ is hydrogen or an alkyl group, R ₂ is hydrogen or a substituted or unsubstituted alkyl group, and n is an integer of 1 to 6). R ₁ is preferably H or CH ₃ and R ₂ is preferably H, CH ₃ or CH ₂ Cl.

  Tables 1 and 2 show the structural formulas and physical properties of representative ones of the phosphate group-containing unsaturated monomers represented by the general formula (1), respectively. These monomers are sold by Unichemical Corporation under the trade name Phosmer (registered trademark). However, the phosphate group-containing unsaturated monomer that can be used in the present invention is not limited to these.

注：(1) Brookfield型粘度計により測定（括弧内はロータNo.を示す）。
(2) 単位は質量％。

Note: (1) Measured with a Brookfield viscometer (the rotor number is shown in parentheses).
(2) The unit is mass%.

  Among the phosphoric acid group-containing unsaturated monomers represented by the general formula (1), from the viewpoint of improving the solvent resistance of the obtained solid polymer electrolyte membrane, acid phosphooxypolyoxypropylene glycol methacrylate (Phosmer PP) is preferred.

（ただしR₃は水素基又はメチル基であり、R₄及びR₅はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、X₁は−O−基又は−NH−基であり、Y₁は置換もしくは無置換の炭素数１〜６のアルキレン基又は置換もしくは無置換の炭素数６〜16のアリーレン基である。）により表される化合物、(b) 下記一般式(3)：

（ただしR₆は水素基又はメチル基であり、R₇及びR₈はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基である。）により表される化合物、(c) 下記一般式(4)：

（ただしR₉は水素基又はメチル基であり、R₁₀及びR₁₁はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、Y₂は置換もしくは無置換の炭素数１〜６のアルキレン基又は置換もしくは無置換の炭素数６〜16のアリーレン基である。）により表される化合物、(d) 下記一般式(5)：

（ただしR₁₂は水素基又はメチル基であり、R₁₃及びR₁₄はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基である。）により表される化合物、(e) 下記一般式(6)：

（ただしR₁₅及びR₁₆はそれぞれ独立に水素基又はメチル基であり、R₁₇は水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、Y₃及びY₄はそれぞれ独立に置換もしくは無置換の炭素数１〜６のアルキレン基又は置換もしくは無置換の炭素数６〜16のアリーレン基である。）により表される化合物、及び(f) １個以上のビニル基を有するヘテロ環状アミン化合物からなる群から選ばれた少なくとも一種である。 (2) Amino group-containing unsaturated monomer The amino group-containing unsaturated monomer is represented by (a) the following general formula (2):

(However, R ₃ is a hydrogen group or a methyl group, R ₄ and R ₅ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and X ₁ is —O -Group or -NH- group, and Y ₁ is a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted arylene group having 6 to 16 carbon atoms. (b) The following general formula (3):

(Wherein R ₆ is a hydrogen group or a methyl group, and R ₇ and R ₈ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms). Compound (c) The following general formula (4):

(Wherein R ₉ is a hydrogen group or a methyl group, R ₁₀ and R ₁₁ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, and Y ₂ is substituted or An unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted arylene group having 6 to 16 carbon atoms), (d) the following general formula (5):

(Wherein R ₁₂ is a hydrogen group or a methyl group, and R ₁₃ and R ₁₄ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms). Compound (e) General formula (6) below:

(However, R ₁₅ and R ₁₆ are each independently a hydrogen group or a methyl group, R ₁₇ is a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and Y ₃ and Y ₄ And each independently represents a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted arylene group having 6 to 16 carbon atoms, and (f) one or more vinyls It is at least one selected from the group consisting of a heterocyclic amine compound having a group.

  Examples of the amino group-containing unsaturated monomer represented by the above formula (2) include N, N-dimethylaminomethyl (meth) acrylate, N, N-diethylaminomethyl (meth) acrylate, and N, N-dipropylamino. Methyl (meth) acrylate, N, N-dibutylaminomethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dipropylaminoethyl ( (Meth) acrylate, N, N-dibutylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-diethylaminopropyl (meth) acrylate, N, N-dipropylaminopropyl (meth) Acrylate, N, N-Dibutylaminopropyl (meth) acrylate, N, N-dimethylaminobutyl (meth) Acrylate, N, N-diethylaminobutyl (meth) acrylate, N, N-dipropylaminobutyl (meth) acrylate, N, N-dibutylaminobutyl (meth) acrylate, N, N-dimethylaminomethyl (meth) acrylamide, N, N-diethylaminomethyl (meth) acrylamide, N, N-dipropylaminomethyl (meth) acrylamide, N, N-dibutylaminomethyl (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dipropylaminoethyl (meth) acrylamide, N, N-dibutylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N- Diethylaminopropyl (meth) acrylamide, N, N-dipropyl Minopropyl (meth) acrylamide, N, N-dibutylaminopropyl (meth) acrylamide, N, N-dimethylaminobutyl (meth) acrylamide, N, N-diethylaminobutyl (meth) acrylamide, N, N-dipropylaminobutyl ( And meth) acrylamide, N, N-dibutylaminobutyl (meth) acrylamide, and the like.

  Examples of the amino group-containing unsaturated monomer represented by the above formula (3) include vinylamine, N-vinyldimethylamine, N-vinyldiethylamine, N-vinyldiphenylamine and the like.

  Examples of the amino group-containing unsaturated monomer represented by the above formula (4) include allylamine, N, N-dimethyl-p-aminostyrene, N, N-diethyl-p-aminostyrene, dimethyl (p-vinylbenzyl). ) Amine, diethyl (p-vinylbenzyl) amine, dimethyl (p-vinylphenethyl) amine, diethyl (p-vinylphenethyl) amine, dimethyl (p-vinylbenzyloxymethyl) amine, dimethyl [2- (p-vinylbenzyl) Oxy) ethyl] amine, diethyl (p-vinylbenzyloxymethyl) amine, diethyl [2- (p-vinylbenzyloxy) ethyl] amine, dimethyl (p-vinylphenethyloxymethyl) amine, dimethyl [2- (p- Vinylphenethyloxy) ethyl] amine, diethyl (p-vinylphenethyloxymethyl) amine, diethyl [2-(p-vinyl phenethyl oxy) ethyl] amine.

  Examples of the amino group-containing unsaturated monomer represented by the above formula (5) include acrylamide, methacrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide and the like.

  Examples of the amino group-containing unsaturated monomer represented by the above formula (6) include diallylmethylamine.

  Examples of the heterocyclic amine compound having one or more vinyl groups include 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 1-vinylimidazole, 2-vinylimidazole, 4-vinylimidazole, 5-vinylimidazole, 1-vinylpyrazole, 3-vinylpyrazole, 4-vinylpyrazole, 1-vinyltriazole, 2-vinylpyrimidine, 4-vinylpyrimidine, 5-vinylpyrimidine, 2-vinylpyrazine, 3-vinylpyridazine, 4-vinylpyridazine, 2-vinyltriazine, N-vinylpyrrole, N-vinylindole, N-vinylcarbazole, N-vinylpyrrolidone, N-vinyl-ε-caprolactam, N-vinylsuccinimide, N-vinylglutarimide, N-vinylphthalimide, etc. Can be mentioned.

  As the amino group-containing unsaturated monomer, from the viewpoint of improving the solvent resistance of the obtained solid polymer electrolyte membrane, those represented by the above formulas (2), (4) and (6) are preferable, Those represented by the above formula (2) are more preferred.

(3) Blending ratio of phosphate group-containing unsaturated monomer and amino group-containing unsaturated monomer The blending ratio of phosphate group-containing unsaturated monomer and amino group-containing unsaturated monomer is Since the acid group-containing unsaturated monomer has two hydroxyl groups per phosphoric acid group, the ratio of the amino group to the phosphoric acid group is preferably in the range of 50 to 180 mol%. When this ratio is less than 50 mol%, the amount of quaternary ammonium salt having crosslinkability is reduced, and the solvent resistance of the resulting polymer is deteriorated. On the other hand, if this ratio exceeds 180 mol%, the ratio of neutralizing phosphate groups becomes too high, and the ratio of acidic phosphate groups in the resulting polymer decreases, resulting in insufficient proton conductivity. This ratio is more preferably in the range of 60 to 150 mol%.

(4) Preparation method of quaternary ammonium salt-containing composition A quaternary ammonium salt-containing composition is an amino group-containing unsaturated compound having a predetermined blending ratio with respect to a phosphate group-containing unsaturated monomer, for example, in a solvent. A monomer, water, and a catalyst to be added as necessary can be added dropwise and treated at a temperature from 0 ° C to the boiling point of the solvent. The amount of water added is about 1% by mass relative to the phosphate group-containing unsaturated monomer. Examples of the solvent include alcohols such as methanol, ethanol and isopropyl alcohol. There is no restriction | limiting in particular in the usage-amount of a solvent, What is necessary is just a grade by which the viscosity of a reaction mixture does not become high too much. If necessary, the solution after the reaction is heated and decompressed to distill off the solvent.

  FIG. 1 shows an example of a neutralization curve when acid phosphooxypolyoxypropylene glycol methacrylate (Phosmer PP) dissolved in methanol is titrated with N, N-dimethylaminoethyl methacrylate (DMAEMA). As shown in FIG. 1, this molar ratio and pH are related when the molar ratio (DMAEMA) / (Phosmer PP) is in the range of 0-2. In FIG. 1, in a region where the molar ratio is more than 0 to less than 1, the half salt and the unreacted phosphate group-containing unsaturated monomer coexist, and the molar ratio is about 1, that is, the pH is 3.9 to 3.9. When it is about 4.5, half salt in which only one of the phosphate groups of Phosmer PP is modified by DMAEMA occupies the majority. Thus, for example, to prepare a composition consisting essentially of a half salt, (i) Phosmer PP and DMAEMA are mixed at a molar ratio of 1: 1 and stirred at the above temperature until the pH is 3.9 to 4.5, or (ii ) DMAEMA may be gradually added dropwise to the Phosmer PP until the pH reaches 3.9 to 4.5. Thus, when a neutralization curve as shown in FIG. 1 is prepared in advance for the phosphate group-containing unsaturated monomer and the amino group-containing unsaturated monomer used as the composition raw material, By measuring the pH when the unsaturated monomer and the amino group-containing unsaturated monomer are mixed, it can be determined whether or not a quaternary ammonium salt-containing composition having a desired composition has been prepared.

（但しR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、R₃は水素基又はメチル基であり、R₄及びR₅はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、X₁は−O−基又は−NH−基であり、Y₁は置換もしくは無置換の炭素数１〜６のアルキレン基又は炭素数６〜12のアリーレン基であり、nは１〜６の整数である。）により表される化合物、(b) 下記一般式(13)：

（但しR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、R₆は水素基又はメチル基であり、R₇及びR₈はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、nは１〜６の整数である。）により表される化合物、(c) 下記一般式(14)：

（但しR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、R₉は水素基又はメチル基であり、R₁₀及びR₁₁はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、Y₂は置換もしくは無置換の炭素数１〜６のアルキレン基又は置換もしくは無置換の炭素数６〜16のアリーレン基であり、nは１〜６の整数である。）により表される化合物、(d) 下記一般式(15)：

（但しR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、R₁₂は水素基又はメチル基であり、R₁₃及びR₁₄はそれぞれ独立に水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、nは１〜６の整数である。）により表される化合物、(e) 下記一般式(16)：

（但しR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、R₁₅及びR₁₆はそれぞれ独立に水素基又はメチル基であり、R₁₇は水素基、炭素数１〜４のアルキル基又は炭素数６〜10のアリール基であり、Y₃及びY₄はそれぞれ独立に置換もしくは無置換の炭素数１〜６のアルキレン基又は置換もしくは無置換の炭素数６〜16のアリーレン基であり、nは１〜６の整数である。）により表される化合物、及び(f) (i) 下記一般式(1)：

（ただしR₁は水素基又はアルキル基であり、R₂は水素基又は置換もしくは無置換のアルキル基であり、nは１〜６の整数である。）により表されるリン酸基含有不飽和単量体を、(ii) １個以上のビニル基を有するヘテロ環状アミンで変性した化合物からなる群から選ばれた少なくとも一種の四級アンモニウム塩を含む。 (5) Quaternary ammonium salt-containing composition The quaternary ammonium salt obtained by the above-described preparation method is such that a part or most of the hydroxyl groups in the phosphate group of the phosphate group-containing unsaturated monomer contain an amino group. Since it has reacted with the amino group of the unsaturated monomer, a hydroxyl group and a quaternary ammonium base coexist in one molecule. Specifically, the quaternary ammonium salt-containing composition obtained by the above-described preparation method includes (a) the following general formula (12):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₃ is a hydrogen group or a methyl group, and R ₄ and R ₅ are each independently hydrogen. Group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, X ₁ is an —O— group or an —NH— group, and Y ₁ is a substituted or unsubstituted carbon atom having 1 to 6 carbon atoms. An alkylene group or an arylene group having 6 to 12 carbon atoms, and n is an integer of 1 to 6.), (b) the following general formula (13):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₆ is a hydrogen group or a methyl group, and R ₇ and R ₈ are each independently hydrogen. A group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and n is an integer of 1 to 6.), (c) the following general formula (14):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₉ is a hydrogen group or a methyl group, and R ₁₀ and R ₁₁ are each independently hydrogen. Group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and Y ₂ is a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted carbon group having 6 to 16 carbon atoms. An arylene group, and n is an integer of 1 to 6.), (d) the following general formula (15):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₁₂ is a hydrogen group or a methyl group, and R ₁₃ and R ₁₄ are each independently hydrogen. A group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and n is an integer of 1 to 6.), (e) the following general formula (16):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₁₅ and R ₁₆ are each independently a hydrogen group or a methyl group, and R ₁₇ is a hydrogen group. Group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, and Y ₃ and Y ₄ are each independently a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted group. A compound having a carbon number of 6 to 16 and n is an integer of 1 to 6), and (f) (i) the following general formula (1):

(Wherein R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, and n is an integer of 1 to 6). The monomer comprises (ii) at least one quaternary ammonium salt selected from the group consisting of compounds modified with a heterocyclic amine having one or more vinyl groups.

  The quaternary ammonium salt-containing composition comprises an unreacted phosphate group-containing unsaturated monomer, an unreacted amino group-containing unsaturated monomer, and an unsaturated monomer in which the phosphate group is neutralized with an amino group. It may also contain at least one selected from the group consisting of a body (an unsaturated monomer in which all of the hydroxyl groups in the phosphate group have reacted with amino groups).

  A quaternary ammonium salt-containing composition does not gel even when refrigerated for about a month. This is presumably due to the coexistence of a hydroxyl group and a quaternary ammonium base in one molecule of a quaternary ammonium salt.

(6) Fluorine group-containing unsaturated monomer Fluorine group-containing unsaturated monomer comprises (a) (meth) acrylic acid esters having at least one fluorine group, and (b) at least one fluorine group. (Meth) acrylic acid having, (c) an alkyl group having at least one fluorine group and / or an olefinically unsaturated monomer having at least one fluorine group and one ethylenically unsaturated bond, and (D) At least one selected from the group consisting of diene unsaturated monomers having an alkylene group containing at least one fluorine group and two ethylenically unsaturated bonds.

（ただしX₃は水素基、フッ素基、少なくとも１個のフッ素基を有する又は有しないメチル基であり、R₂₅は少なくとも１個のフッ素基を有する又は有しないアルキル基である。）により表されるものが好ましい。 As fluorine group-containing (meth) acrylic acid esters, the following general formula (7):

(Wherein X ₃ is a hydrogen group, a fluorine group, a methyl group having or not having at least one fluorine group, and R ₂₅ is an alkyl group having or not having at least one fluorine group). Those are preferred.

In the general formula (7), R ₂₅ preferably has 1 to 10 carbon atoms, and more preferably 1 to 5 carbon atoms. When R ₂₅ is an alkyl group containing a fluorine group and has 2 or more carbon atoms, it is preferable that all of the hydrogen groups of the terminal methyl group are substituted with fluorine groups. R ₂₅ may be a linear structure or a branched structure. R ₂₅ may have a halogen atom other than fluorine. R ₂₅ may have a hetero atom. Examples of the hetero atom include an etheric oxygen atom and a thioetheric sulfur atom contained between carbon-carbon bonds in R ₂₅ .

  Examples of fluorine group-containing (meth) acrylic esters represented by the general formula (7) include 2,2,2-trifluoroethyl acrylate, 2,2,2-trifluoroethyl methacrylate, and tertiary butyl. Examples include α- (trifluoromethyl) acrylate, trifluoroethyl-α- (trifluoromethyl) acrylate, perfluorooctylethyl (meth) acrylate, and the like. Among these, as the fluorine group-containing (meth) acrylic acid esters, 2,2,2-trifluoroethyl methacrylate and tertiary butyl-α- (trifluoromethyl) acrylate are preferable.

（ただしX₄はフッ素基又は少なくとも１個のフッ素基を有するメチル基である。）により表されるものが好ましい。上記一般式(8)においてX₄はフッ素基又はパーフルオロメチル基であるのがより好ましい。フッ素基含有（メタ）アクリル酸類としては、α−（トリフルオロメチル）アクリル酸が特に好ましい。 As fluorine-containing (meth) acrylic acids, the following general formula (8):

(Wherein X ₄ is a fluorine group or a methyl group having at least one fluorine group) is preferred. In the general formula (8), X ₄ is more preferably a fluorine group or a perfluoromethyl group. As the fluorine group-containing (meth) acrylic acid, α- (trifluoromethyl) acrylic acid is particularly preferable.

（ただしRf₁は少なくとも１個のフッ素基を含有するアルキル基であり、X₅、X₆及びX₇はそれぞれ独立に水素基又はフッ素基である。）又は下記一般式(10)：

（ただしX₈、X₉及びX₁₀はそれぞれ独立にフッ素基又は少なくとも１個のフッ素基を有するメチル基であり、X₁₁は水素基、フッ素基、その他のハロゲン、少なくとも１個のフッ素基を有するメチル基、フッ素基を有しないアルキル基、又はフッ素基を有するもしくは有しないアルコキシ基である。）により表されるものが好ましい。 The fluorine-containing olefinically unsaturated monomer is represented by the following general formula (9):

(Where Rf ₁ is an alkyl group containing at least one fluorine group, and X ₅ , X ₆ and X ₇ are each independently a hydrogen group or a fluorine group) or the following general formula (10):

(However, X ₈ , X ₉ and X ₁₀ are each independently a fluorine group or a methyl group having at least one fluorine group, and X ₁₁ is a hydrogen group, a fluorine group, other halogens, or at least one fluorine group. A methyl group having an alkyl group having no fluorine group, or an alkoxy group having or not having a fluorine group.

The alkyl group Rf ₁ containing a fluorine group in the general formula (9) is preferably a perfluoroalkyl group. Rf ₁ preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms. Rf ₁ may be a linear structure or a branched structure, but is preferably a linear structure. Rf ₁ may have a halogen atom other than fluorine. Rf ₁ may have a hetero atom. Examples of the hetero atom include an etheric oxygen atom and a thioetheric sulfur atom contained between carbon-carbon bonds in Rf ₁ .

（但しRf₁は上記式(9)と同じである。）により表されるものがより好ましい。 As the fluorine group-containing olefinically unsaturated monomer represented by the general formula (9), the following general formula (17):

(Where Rf ₁ is the same as that in the above formula (9)) is more preferable.

  Examples of the fluorine group-containing olefinically unsaturated monomer represented by the general formula (17) include (perfluorobutyl) ethylene, (perfluorohexyl) ethylene, (perfluorooctyl) ethylene, and (perfluorodecyl) ethylene. Etc. Of these, (perfluorobutyl) ethylene, (perfluorohexyl) ethylene and (perfluorooctyl) ethylene are preferable as the fluorine group-containing olefinic unsaturated monomer.

X ₈ , X ₉ and X _{10 in the} general formula (10) are preferably a fluorine group or a perfluoromethyl group. When X ₁₁ in the general formula (10) is an alkyl group, an alkoxy group or a fluorine group-containing alkoxy group, the carbon number thereof is preferably 1 to 10. Examples of the fluorine-containing olefinically unsaturated monomer represented by the general formula (10) include hexafluoropropene, chlorotrifluoroethylene, 1-methoxy- (perfluoro-2-methyl-1-propene), and the like. Can be mentioned.

（ただしRf₂は少なくとも１個のフッ素基を含有するアルキレン基であり、X₁₂、X₁₃、X₁₄、X₁₅、X₁₆及びX₁₇はそれぞれ独立に水素基又はフッ素基である。）により表されるものが好ましい。 As the fluorine-containing diene unsaturated monomer, the following general formula (11):

(Wherein Rf ₂ is an alkylene group containing at least one fluorine group, and X ₁₂ , X ₁₃ , X ₁₄ , X ₁₅ , X ₁₆ and X ₁₇ are each independently a hydrogen group or a fluorine group). Those represented are preferred.

The alkylene group Rf ₂ containing at least one fluorine group in the general formula (11) is preferably a perfluoroalkylene group. Rf ₂ preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms. Rf ₂ may have a linear structure or a branched structure, but preferably has a linear structure. Rf ₂ may have a halogen atom other than fluorine. Rf ₂ may have a hetero atom and / or a hetero atom group. The hetero atom, carbon in Rf ₂ - etheric oxygen atoms contained in the carbon-carbon bond, and the like thioether sulfur atom. Examples of the hetero atom group include an ester bond.

（但しRf₂は上記式(11)と同じである。）により表されるものがより好ましい。 Examples of the fluorine-containing olefinically unsaturated monomer represented by the general formula (11) include the following general formula (18):

(However, Rf ₂ is the same as the above formula (11).)

  Examples of the fluorine-containing diene unsaturated monomer represented by the general formula (18) include 1,4-divinyl (perfluorobutylene) (also known as 1,4-divinyloctafluorobutane), 1,6- Divinyl (perfluorohexylene) (alias: 1,6-divinyldodecafluorohexane) and 1,8-divinyl (perfluorooctylene) (alias: 1,8-divinylhexadecafluorooctane) are preferred.

  Among the four types of fluorine group-containing unsaturated monomers, fluorine group-containing diene unsaturated monomers are preferable from the viewpoint of having excellent curability and capable of forming intermolecular crosslinks in the copolymer. Fluorine group-containing (meth) acrylic acid esters and fluorine group-containing (meth) acrylic acids have similar behavior to fluorine group-containing olefinic unsaturated monomers, despite having a small amount of fluorine groups in the molecule. Show.

  The four types of fluorine group-containing unsaturated monomers may be used alone or in combination of two or more. When using 2 or more types together, for example, fluorine group-containing olefinic unsaturated monomer and / or fluorine group-containing diene unsaturated monomer, fluorine group-containing (meth) acrylic acid esters and / or fluorine group-containing The composition etc. which mixed (meth) acrylic acid can be mentioned.

(7) Content of Fluorine Group-Containing Unsaturated Monomer The upper limit of the content of the fluorine group-containing unsaturated monomer is preferably 80 by weight with respect to 100 as the quaternary ammonium salt-containing composition.

[2] Other unsaturated monomers The monomer composition for solid polymer electrolyte may contain other unsaturated monomers other than the above (a) to (c) which can be copolymerized therewith. Good. Other unsaturated monomers can be roughly divided into the following two groups (1) and (2).

(1) Unsaturated monomer containing functional group An unsaturated monomer containing a functional group is a compound having at least one functional group and at least one ethylenically unsaturated bond in the molecule. Examples of the functional group include an acidic group, an alcoholic hydroxyl group, and an alkylamino group (including those having an amide group). As the acidic group, at least one selected from the group consisting of a phosphorus acid residue, a sulfonic acid group, and a carboxylic acid group is preferable. Examples of the skeleton having an ethylenically unsaturated bond include a (meth) acrylate skeleton and a (meth) allyl ester skeleton.

（ただしR₁₈及びR₂₁はそれぞれ独立に水素基又はアルキル基であり、R₁₉及びR₂₀はそれぞれ独立に水素基又は置換もしくは無置換のアルキル基であり、m及びpはそれぞれ独立に１〜６の整数である。）により表されるリン酸基含有ジエステル系不飽和単量体が好ましい。このリン酸基含有ジエステル系不飽和単量体を用いることにより、得られる固体高分子電解質膜の耐溶剤性が向上する。リン酸基含有ジエステル系不飽和単量体としては、下記式(20)；

により表されるジ（メタクリロイルオキシエチル）ホスフェートが好ましい。 (i) Phosphoric acid residue-containing unsaturated monomer As the phosphoric acid residue-containing unsaturated monomer, the following formula (19):

(However, R ₁₈ and R ₂₁ are each independently a hydrogen group or an alkyl group, R ₁₉ and R ₂₀ are each independently a hydrogen group or a substituted or unsubstituted alkyl group, and m and p are each independently 1 to 1) The phosphoric acid group-containing diester unsaturated monomer represented by the formula (6) is preferred. By using this phosphoric acid group-containing diester unsaturated monomer, the solvent resistance of the obtained solid polymer electrolyte membrane is improved. Examples of phosphoric acid group-containing diester unsaturated monomers include the following formula (20):

Di (methacryloyloxyethyl) phosphate represented by is preferred.

（ただしR₂₆及びR₂₉はそれぞれ独立に水素基又はアルキル基であり、R₂₇及びR₂₈はそれぞれ独立に水素基又は置換もしくは無置換のアルキル基であり、s及びtはそれぞれ独立に１〜６の整数である。）により表されるピロリン酸基含有不飽和単量体を用いてもよい。式(21)により表されるピロリン酸基含有不飽和単量体としては、下記式(22)；

により表されるジ（メタクリロイルオキシエチル）アシッド・ピロホスフェートが好ましい。 As the phosphoric acid residue-containing unsaturated monomer, the following general formula (21):

(Wherein R ₂₆ and R ₂₉ are each independently a hydrogen group or an alkyl group, R ₂₇ and R ₂₈ are each independently a hydrogen group or a substituted or unsubstituted alkyl group, and s and t are each independently 1 to 1) It is also possible to use a pyrophosphate group-containing unsaturated monomer represented by the following formula: As the pyrophosphate group-containing unsaturated monomer represented by the formula (21), the following formula (22);

Di (methacryloyloxyethyl) acid pyrophosphate represented by is preferred.

  When using together a phosphate group-containing unsaturated monomer and a phosphate group-containing diester unsaturated monomer and / or a pyrophosphate group-containing unsaturated monomer (phosphate group-containing unsaturated monomer) The blending molar ratio of / (phosphate group-containing diester unsaturated monomer and / or pyrophosphate group-containing unsaturated monomer) is preferably 1 / 0.1 to 1/2.

により表されるメタクロイル・オキシエチルアシッドホスフェート・モノエタノールアミン塩が挙げられる。この錯塩は、ユニケミカル（株）から商品名「Phosmer MH」として販売されている。 As other exemplary compounds of the unsaturated monomer containing a phosphorus acid residue, the phosphate group-containing unsaturated monomer represented by the above formula (1) is a hydrocarbon group-containing ammonium ion or alkanolamine. The thing which formed the complex salt with the residue is also mentioned. The counter ions of such complex salts include primary, secondary, tertiary or quaternary alkyl groups, allyl groups, aralkyl groups, etc. ammonium ions and mono-, di- or trialkanolamine residues. In particular, N ⁺ R ³⁰ _4-f (OH) _f (wherein R ³⁰ is an alkyl group having 1 to 18 carbon atoms, an aromatic group having 6 to 12 carbon atoms, and an alicyclic group having 6 to 12 carbon atoms. At least one selected from the group consisting of f and f represents a positive integer of 1 to 3). As a specific compound of the complex salt, the following general formula (23):

And methacryloyl oxyethyl acid phosphate monoethanolamine salt represented by This complex salt is sold by Unichemical Co., Ltd. under the trade name “Phosmer MH”.

（ただしR₂₂は水素基又はメチル基である。）により表される化合物、下記一般式(25)：

（ただしR₂₃は水素基又はメチル基であり、Y₅は置換もしくは無置換の炭素数１〜６のアルキレン基又は炭素数６〜12のアリーレン基である。）により表される化合物、及び下記一般式(26)：

（ただしR₂₄は水素基又はメチル基であり、X₂は−O−基又は−NH−基であり、Y₆は置換もしくは無置換の炭素数１〜６のアルキレン基又は炭素数６〜12のアリーレン基である。）により表される化合物からなる群から選ばれた少なくとも一種が好ましい。 (ii) Sulfonic acid group-containing unsaturated monomer Examples of the unsaturated monomer-containing unsaturated monomer include the following general formula (24):

(Wherein R ₂₂ is a hydrogen group or a methyl group), a compound represented by the following general formula (25):

Wherein R ₂₃ is a hydrogen group or a methyl group, and Y ₅ is a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or an arylene group having 6 to 12 carbon atoms, and the following: Formula (26):

(Wherein R ₂₄ is a hydrogen group or a methyl group, X ₂ is an —O— group or an —NH— group, and Y ₆ is a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or 6 to 12 carbon atoms. And at least one selected from the group consisting of compounds represented by formula (1):

  Examples of the sulfonic acid group-containing unsaturated monomer represented by any one of the general formulas (24) to (26) include allyl sulfonic acid, methallyl sulfonic acid, and vinyl sulfone. Acid, p-styrenesulfonic acid, (meth) acrylic acid butyl-4-sulfonic acid, (meth) acrylooxybenzenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid (tertiary butylacrylamidesulfonic acid), etc. Can be mentioned. Preferred are vinyl sulfonic acid, p-styrene sulfonic acid and tertiary butyl acrylamide sulfonic acid. However, allyl sulfonic acid and methallyl sulfonic acid are used in small quantities because the allyl group causes degradative chain transfer. Is preferred. Specifically, the total amount of the monomer composition for solid polymer electrolyte is 100% by mass, and the amount used is at most about 10% by mass.

  The sulfonic acid group may be dissociated or may form a complex salt. When forming a complex salt, it is preferable to form a complex salt with an ammonium ion, an amine residue or an alkali metal as described for the phosphoric acid residue-containing unsaturated monomer in (i) above.

(iii) Unsaturated monomer containing carboxylic acid group Examples of unsaturated monomers containing carboxylic acid groups include (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, maleic acid. An acid anhydride etc. are mentioned. These may be used alone or in combination of two or more.

(iv) Unsaturated monomer containing alcoholic hydroxyl group Examples of unsaturated monomer containing alcoholic hydroxyl group include glycerol dimethacrylate [for example, “Blemmer GMR” and “Blemmer GMR-R” (Nippon Yushi ( Etc.)], glycerol methacrylate acrylate [e.g., trade name "Blenmer GAM", "Blenmer GAM-R" (Nippon Yushi Co., Ltd.)], 1,6-hexanediol diglycidyl ether acrylate [e.g., trade name “NK Oligo EA-5521” (manufactured by Shin-Nakamura Chemical Co., Ltd.), etc., 1,4-butanediol diglycidyl ether acrylate [eg, trade name “NK Oligo EA-5520” (manufactured by Shin-Nakamura Chemical Co., Ltd.) ), Etc.], bisphenol A type epoxy acrylate [for example, “NK Oligo EA-1020” (manufactured by Shin-Nakamura Chemical Co., Ltd.), etc.], and 2-hydroxymethyl And 2-hydroxy (meth) acrylates such as ru (meth) acrylate and 2-hydroxyethyl (meth) acrylate. Among them, glycerol dimethacrylate, glycerol methacrylate acrylate, 1,6-hexanediol diglycidyl ether acrylate, 1,4-butanediol diglycidyl ether acrylate and bisphenol A type epoxy acrylate have two ethylenically unsaturated groups in the molecule. It is preferable from the point of having.

(2) Unsaturated monomer that does not contain a functional group As the unsaturated monomer that does not contain a functional group, other than those described in (1), at least one ethylenically unsaturated group in the molecule that is not gas at normal temperature. Although all unsaturated monomers having a saturated bond are targeted, (meth) acrylonitrile; (meth) acrylic acid esters such as methyl (meth) acrylate, ethyl (meth) acrylate, alkyl (meth) acrylate; (Meth) acrylic amides; substituted or unsubstituted styrenes; vinyls such as vinyl chloride and vinyl acetate are preferably used. Ethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, hexamethylenediol di (meth) acrylate, divinylbenzene, and the like containing a plurality of ethylenically unsaturated bonds in one molecule are also resistant to the copolymer. Used for the purpose of improving chemical properties.

(3) Ratio of use of each unsaturated monomer About the blending ratio of the quaternary ammonium salt-containing composition (A), the fluorine group-containing unsaturated monomer (c) and the other unsaturated monomer (d), It is preferable that the upper limit of the sum of (c) and (d) is 80 with respect to (A) 100 in weight ratio. The weight ratio of (A) / (total of (c) and (d)) is more preferably 80/20 to 40/60. Further, regarding the blending ratio of the fluorine group-containing unsaturated monomer (c), the unsaturated monomer containing the functional group (d-1), and the unsaturated monomer having no functional group (d-2), The weight ratio of (d-1) / (total of (c) and (d-2)) is preferably 100/0 to 50/50.

[3] Other polymers that can be mixed In order to further improve the film-forming properties when producing a solid polymer electrolyte membrane, the strength, hydrophobicity, solvent resistance, etc. of the solid polymer electrolyte membrane, Other polymers that are compatible with the copolymer constituting the electrolyte membrane can be mixed. Examples of other polymers include polyamide resin, polyvinyl alcohol, polyacrylamide, polyacrylic acid, melamine resin, cellulose, and modified products thereof. As the polyamide resin, N-alkoxyalkylated polyamides described in JP-A No. 2003-138088 are preferable.

[4] Method for Producing Solid Polymer Electrolyte Membrane The solid polymer electrolyte membrane of the present invention is prepared by preparing the above-mentioned monomer composition for a solid polymer electrolyte and adding a photosensitizer thereto. Cast on a plate coated with a material that does not adhere to the monomer composition (fluorine polymer, etc.), cover with a UV transparent plate, and then irradiate with UV to release the unsaturated monomer (both) It can be produced by polymerization.

As a photosensitizer to be added to the monomer composition for solid polymer electrolyte,
(i) adjacent polyketone compounds represented by R— (CO) _x —R ′ (R, R ′ = hydrogen group or hydrocarbon group, x = 2 to 3) (for example, diacetyl, dibenzyl, etc.),
(ii) α-carbonyl alcohols represented by R—CO—CHOH—R ′ (R, R ′ = hydrogen group or hydrocarbon group) (for example, benzoin),
(iii) acyloin ethers represented by R—CH (OR ″) — CO—R ′ (R, R ′, R ″ = hydrocarbon group) (for example, benzoin methyl ether),
(iv) α-substituted acyloins represented by Ar—CR (OH) —CO—Ar (Ar = aryl group, R = hydrocarbon group) (for example, α-alkylbenzoin), and
(v) There are polynuclear quinones (for example, 9,10-anthraquinone, etc.).
These photosensitizers can be used alone, but a plurality of them may be used in combination.

  The usage-amount of a photosensitizer is the range of 0.01-3 mass% with respect to the mass of the monomer composition for solid polymer electrolytes, Preferably it is the range of 0.01-1.5 mass%. If it is less than 0.01% by mass, polymerization is not completed within a predetermined ultraviolet irradiation time, and unreacted monomers remain. This is not preferable, and if it exceeds 3% by mass, the degree of polymerization of the resulting polymer is lowered. This is not preferable because the polymer tends to be colored.

  The UV transmissive plate and support substrate used for UV irradiation polymerization of the monomer composition for solid polymer electrolytes have not only high UV transmittance but also heat resistance to withstand temperature rise during UV irradiation polymerization. In addition, it is necessary that the monomer composition for a solid polymer electrolyte and the solid polymer electrolyte obtained by polymerizing the monomer composition are not adhered and have good releasability.

  The glass plate usually used as a support substrate is very good in terms of UV transmittance and heat resistance, but is in close contact with the solid polymer electrolyte obtained by polymerization of the monomer composition for solid polymer electrolyte. It is preferable to use it after applying a silicone-based or fluorine-based release agent on the surface, or by attaching a thin fluororesin-based transparent film.

  In addition to glass flat plates, the supporting substrate has good UV transmittance such as polyperfluorovinyl ether resin (PFA) and polyvinylidene fluoride resin (PVDF), as well as poly-3-methylpentene resin and polypropylene resin. A resin flat plate having heat resistance of 100 ° C. or higher can be used.

After casting the polymer composition for the solid polymer electrolyte, it is covered with an ultraviolet transmissive plate and irradiated with ultraviolet rays, or impregnated with or coated with the monomer composition for the solid polymer electrolyte. In order to irradiate ultraviolet rays while sandwiching between the supporting substrates, it is necessary to squeeze out air and an extra monomer component for the solid polymer electrolyte to the outside of the system. For example, as shown in FIG. 2, the composition 1 is sandwiched between two support substrates 2 and 2, and UV irradiation is carried out while keeping it horizontal with a pressure applied evenly and stopped with a clip or clamp 3. Is preferred. Irradiation is performed for at least one side for 1 to 15 minutes. When irradiation is performed alternately on the front and back sides, it is performed for 1 to 15 minutes on one side. The ultraviolet irradiation intensity at the time of photopolymerization is 5 to 100 μW / cm ² , preferably 10 to 80 μW / cm ² . The ultraviolet irradiation distance is appropriately set so as to be sufficiently cured within the above irradiation time range. The film obtained by the photopolymerization method is preferably heat-treated at 100 to 140 ° C. for about 1 to 15 minutes for the purpose of improving mechanical strength and solvent resistance.

  In the present invention, a low-boiling solvent such as methanol may be added as a diluent for the purpose of assisting the dissolution of the photosensitizer in the monomer composition for a solid polymer electrolyte.

  After impregnating or applying the monomer composition for a solid polymer electrolyte into a reinforcing material, the reinforcing material is sandwiched between UV permeable support substrates and irradiated with ultraviolet rays to photopolymerize the unsaturated monomer. Alternatively, a composite film may be formed.

The reinforcing materials to be used can be roughly divided into the following three groups.
(i) Reinforcing material made of inorganic fiber Examples of the reinforcing material include woven fabric, nonwoven fabric, and paper made of glass fiber, alumina fiber, rock wool fiber, slag fiber and the like. The basis weight of the reinforcing material made of inorganic fibers is 10 to 60 mg / cm ² , preferably 10 to 40 mg / cm ² , and the thickness is in the range of 1 μm to 60 μm, preferably 5 μm to 40 μm.

(ii) Reinforcing materials made of organic fibers Usually, nylon fibers, polyester fibers, acrylic fibers, etc. used for clothing, and woven fabrics, nonwoven fabrics, papers, etc. made of aramid fibers used for industrial use are listed. Examples of the nonwoven fabric include polypropylene nonwoven fabric. However, since the temperature of the composite system may rise to ˜100 ° C. during ultraviolet irradiation, it is necessary to have heat resistance that can withstand it. The basis weight and thickness of the reinforcing material made of organic fibers are the same as in the case of (i). However, if the monomer composition for the solid polymer electrolyte to be impregnated contains an unsaturated monomer having a strong acid group such as a sulfonic acid group, the woven fabric, nonwoven fabric, paper, etc. made of nylon fiber have weak acid resistance. Unsuitable.

(iii) Resin film General-purpose resins such as polyethylene resin, polypropylene resin, poly-3-methylpentene resin, nylon-6 resin, polyester resin, thermoplastic polyurethane resin, heat-resistant resin such as polysulfone resin, polyethersulfone resin, A film formed from a polyether ether ketone resin, an aramid resin, a polyimide resin, a fluorine resin, or the like is preferable. The resin film may be a film having micropores or a film having no micropores, but the former is preferable. However, when the monomer composition for the solid polymer electrolyte to be impregnated contains an unsaturated monomer having a strong acid group such as a sulfonic acid group, the nylon film is not suitable because the acid resistance is not strong.

  In the case of a microporous film, the pore size of the micropore is preferably as small as possible, and is preferably a submicron diameter. Further, the overall open area ratio is preferably as large as possible, and particularly preferably 40 to 50% (surface area). The thickness of the resin film is preferably 1 μm to 40 μm, and more preferably 5 μm to 25 μm.

  The proportion of the reinforcing material and the solid polymer electrolyte monomer composition used is the affinity of the reinforcing material to the solid polymer electrolyte monomer composition, in other words, the solid polymer electrolyte monomer composition. Generally, it is in the range of reinforcing material / monomer composition for solid polymer electrolyte = 1/20 to 1/2 (mass ratio), although it varies greatly depending on the absorbability.

  In the present invention, for the purpose of reducing the viscosity of the monomer composition for a solid polymer electrolyte, facilitating the impregnation of the reinforcing material, reducing the amount of adhesion to the reinforcing material, and reducing the thickness of the composite membrane. Also, a low boiling point solvent such as methanol can be added as a diluent.

[5] Characteristics of the solid polymer electrolyte membrane The solid polymer electrolyte membrane of the present invention has a methanol extraction rate at room temperature / 24 hours of 12% or less for a membrane dried at room temperature, and 7 for a membrane dried at 130 ° C. % Or less and excellent in solvent resistance. The solid polymer electrolyte membrane of the present invention is excellent in solvent resistance because the quaternary ammonium salt constituting the solid polymer electrolyte membrane is converted into (a) a phosphate group-containing unsaturated monomer in one molecule. Since it has an ethylenically unsaturated bond derived from and (b) an ethylenically unsaturated bond derived from an amino group-containing unsaturated monomer, it has a crosslinked structure formed by these unsaturated bonds. Guessed. In the solid polymer electrolyte membrane of the present invention, the amino group is bonded to the hydrocarbon skeleton derived from the ethylenically unsaturated bond directly or via an alkylene group and the like, and is bonded to the phosphate group. The bond between the group and the amino group is strong and difficult to dissociate. For this reason, it is excellent in solvent resistance even at relatively high temperatures.

The solid polymer electrolyte membrane of the present invention has excellent proton conductivity of 10 ⁻³ to 10 ⁻⁵ S · cm ^{−1 at} a relative humidity of 90% / temperature of 20 to 80 ° C., and the temperature dependence of the proton conductivity. The nature is small. Among them, a membrane containing a sulfonic acid group-containing unsaturated monomer is particularly excellent in proton conductivity. Here, proton conductivity is obtained from the resistance value of the sample obtained by performing plane complex impedance analysis on the data obtained by measurement using the complex impedance method and processing the cole-cole plot figure. Is.

  The thickness of the solid polymer electrolyte (composite) membrane is usually 300 μm or less, preferably 10 to 200 μm.

  The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

（但しn＝５〜６である。）により表されるハーフ塩を主成分とする組成物が得られたと判断した。 Examples 1 and 2
(Preparation of quaternary ammonium salt-containing composition)
77.3 g (0.157 mol) of acid phosphooxypolyoxypropylene glycol methacrylate (trade name “Phosmer PP”, manufactured by Unichemical Co., Ltd.) and 0.77 g of water were dissolved in 350 mL of methanol at room temperature. 28.3 g (0.180 mol) of N, N-dimethylaminoethyl methacrylate (DMAEMA) was added dropwise to the solution and stirred until the pH was 5.3. The obtained reaction solution was concentrated under reduced pressure at 40 ° C. to obtain 100.1 g of a product. The double bond purity (bromine addition method) of the product was 84.6%, and the acid value (using 1N KOH aqueous solution) was 134.1 mg [see half salt consisting of Phosmer PP and DMAEMA (see the following formula (27)) ) Theoretical acid value: 87.4 mg / g. Since KOH, which is a strong base, is used, it is presumed that a part of DMAEMA that forms a salt with Phosmer PP is substituted with KOH and measured as a value higher than the original acid value (the same applies hereinafter). ]. From this, the following equation (27):

(However, n = 5-6) It was judged that the composition which has the half salt represented by these as a main component was obtained.

(Preparation of solid polymer electrolyte membrane)
A solid polymer electrolyte membrane was produced using the monomer composition (PP-DM (I)) containing the obtained half salt. Table 3 shows the raw materials of the unsaturated monomers used and their blending ratios. First, as a photosensitizer, [Irgacure 651 (2,2-dimethoxy-1,2-diphenylethane-1-one) + Irgacure 500 (1-hydroxycyclohexyl phenyl ketone, Benzophenone) = 1 wt% + 0.5 wt%] (vs total monomers). Next, as shown in FIG. 2 and FIG. 3, the obtained composition 1 was cast on a glass flat plate 2 to which a fluororesin film was attached, and the glass flat plate 2 to which a fluororesin film was attached was put thereon, and 2 The composition 1 is sandwiched between two glass flat plates 2 and 2, and a high pressure mercury lamp (Cure Arab HLR-1000F-22 manufactured by Sen Special Light Source Co., Ltd., wavelength: 365 nm) is used. A solid polymer electrolyte membrane was prepared by photopolymerization by irradiation for 7 to 8 minutes from one side at / cm ² (irradiation distance: 25 cm). The obtained film was heat-treated at 130 ° C. for 5 minutes. Table 3 shows the methanol extraction rate and the like of the produced solid polymer electrolyte composite membrane.

Note: (1) Acid phosphooxypolyoxypropylene glycol methacrylate (Phosmer PP, molecular weight: 485) and N, N-dimethylaminoethyl methacrylate (DMAEMA, molecular weight: 157) molar ratio (DMAEMA) / (Phosmer PP) = Composition reacted in 1.15.
(2) A composition comprising methacryloyloxyethyl phosphate (Phosmer M, molecular weight: 210) and di (methacryloyloxyethyl) phosphate (molecular weight: 322) in a theoretical molar ratio of 1: 1.
(3) Acrylonitrile (molecular weight: 53).
(4) 2,2,2-trifluoroethyl methacrylate (molecular weight: 168).
(5) Measure the mass loss after immersing the membrane in a large excess of methanol at room temperature for 24 hours.

Comparative Examples 1-4
(Preparation of composition for forming solid polymer electrolyte)
The reaction was conducted in the same manner as in Example 1 except that 77.3 g (0.157 mol) of Phosmer PP, 53.2 g (0.34 mol) DMAEMA, and 0.77 g of water were used until the pH was 7.0. The obtained reaction solution was concentrated under reduced pressure at 40 ° C. to obtain 124.0 g of a product. Since the pH was almost neutralized to 7.0, it was judged that a composition containing an unsaturated monomer whose phosphate group was neutralized with an amino group as a main component was obtained. The double bond purity (bromine addition method) of the product was 100%, and the acid value (using 1N aqueous KOH solution) was 69.6 mg.

(Preparation of solid polymer electrolyte membrane)
Using the resulting monomer composition (PP-DM (II)), a solid polymer electrolyte membrane was produced in the same manner as in Example 1. Table 4 shows the unsaturated monomer materials used and the blending ratios thereof. Table 4 shows the methanol extraction rate and the like of the produced solid polymer electrolyte composite membrane.

Comparative Examples 5 and 6
A solid polymer electrolyte membrane was prepared in the same manner as in Example 1 using the unsaturated monomer shown in Table 4. Table 4 shows the methanol extraction rate and the like of the produced solid polymer electrolyte composite membrane.

Table 4 (continued)

Note: (1) Acid phosphooxypolyoxypropylene glycol methacrylate (Phosmer PP, molecular weight: 485) and N, N-dimethylaminoethyl methacrylate (DMAEMA, molecular weight: 157) molar ratio (DMAEMA) / (Phosmer PP) = Composition reacted in 2.17.
(2) A composition comprising methacryloyloxyethyl phosphate (Phosmer M, molecular weight: 210) and di (methacryloyloxyethyl) phosphate (molecular weight: 322) in a theoretical molar ratio of 1: 1.
(3) Styrene (molecular weight: 104).
(4) Acrylonitrile (molecular weight: 53).
(5) 2,2,2-trifluoroethyl methacrylate (molecular weight: 168).
(6) Measure the mass loss after immersing the membrane in a large excess of methanol at room temperature for 24 hours.

  From the results shown in Tables 3 and 4, it can be seen that the membranes of Examples 1 and 2 have a methanol extraction rate of 7% or less and excellent methanol resistance. Comparative Examples 5 and 6 use only a phosphate group-containing unsaturated monomer that does not contain a quaternary ammonium base as a monomer that contains an acidic group. The nature is greatly inferior. In addition, although the thickness of the solid polymer electrolyte membrane of an Example is the range of 70-170 micrometers, it is set as desired thickness by adjusting suitably the quantity of the monomer composition pinched | interposed into a glass plate, and the pressure which squeezes it out. be able to.

(Evaluation of proton conductivity)
Proton conductivity was measured using the complex impedance method. Samples cut from the membranes of Examples 1 and 2 and Comparative Examples 1 to 4 prepared by the above-described method were sandwiched between two platinum electrodes, and filled in a cell of an electrochemical interface potentiostat manufactured by Toyo Corporation. . The cell impedance was measured at a measurement frequency range of 1 MHz, a relative humidity of 90%, and a measurement temperature range of 20 to 80 ° C. The obtained data was subjected to planar complex impedance analysis, and the proton conductivity was obtained from the resistance value of the sample obtained by performing the cole-cole plot graphic processing on the result. The results are shown in FIGS.

The proton conductivity of the solid polymer electrolyte membranes of Examples 1 and 2 is in the order of 10 ⁻³ to 10 ⁻⁵ S · cm ⁻¹ under conditions of RH 90% / 20 to 80 ° C., and the phosphate group is a functional group. It can be seen that the polymer electrolyte is a good level and the temperature dependence of proton conductivity is small. On the other hand, the membranes of Comparative Examples 1 to 4 do not contain the half salt represented by the above formula (27) or contain very little, so even if the proton conductivity is RH 90% / 80 ° C., 10 ⁻⁴ It was in the order of S · cm ⁻¹ and was inferior.

It is a graph which shows the example of the neutralization curve which titrated acid phosphooxy polyoxypropylene glycol methacrylate with N, N- dimethylamino ethyl methacrylate. It is a side view which shows the state which pinched | interposed the composition for solid polymer electrolytes between two glass flat plates. It is a top view which shows the state which pinched | interposed the composition for solid polymer electrolytes between two glass flat plates. It is a graph which shows the relationship between temperature T (degreeC) and proton conductivity log ((sigma) / S * cm < ^-1 >) by a cole-cole plot about the solid polymer electrolyte membrane of Example 1,2. It is a graph which shows the relationship between temperature T (degreeC) and proton conductivity log ((sigma) / S * cm < ^-1 >) by a cole-cole plot about the solid polymer electrolyte membrane of Comparative Examples 1-4.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Composition 2 ... Glass flat plate 3 ... Clip

Claims (9)

(A) A phosphate group-containing unsaturated monomer (a) having a phosphate group and an ethylenically unsaturated bond, and a substituted or unsubstituted amino group and an amino group-containing unsaturated monomer having an ethylenically unsaturated bond The body (b) is reacted in the range where the ratio of the amino group of (b) to the phosphate group of (a) is 50 to 180 mol%, and (a) is modified with (b). A monomer composition comprising a quaternary ammonium salt;
(B) a solid polymer electrolyte membrane obtained by copolymerizing at least a fluorine group-containing unsaturated monomer (c),
(a) is the following general formula (1):

(Wherein R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, and n is an integer of 1 to 6),
(b) is the following general formula (2):

(However, R ₃ is a hydrogen group or a methyl group, R ₄ and R ₅ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and X ₁ is —O -Group or -NH- group, and Y ₁ is a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted arylene group having 6 to 16 carbon atoms), General formula (3):

Wherein R ₆ is a hydrogen group or a methyl group, and R ₇ and R ₈ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms. The following general formula (4):

(Wherein R ₉ is a hydrogen group or a methyl group, R ₁₀ and R ₁₁ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, and Y ₂ is substituted or An unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted arylene group having 6 to 16 carbon atoms), the following general formula (5):

Wherein R ₁₂ is a hydrogen group or a methyl group, and R ₁₃ and R ₁₄ are each independently a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms. The following general formula (6):

(However, R ₁₅ and R ₁₆ are each independently a hydrogen group or a methyl group, R ₁₇ is a hydrogen group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and Y ₃ and Y ₄ Are each independently a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted arylene group having 6 to 16 carbon atoms, and a hetero compound having one or more vinyl groups. Is at least one selected from the group consisting of cyclic amine compounds,
(c) is (i) (meth) acrylic acid ester having at least one fluorine group, (ii) (meth) acrylic acid having at least one fluorine group, (iii) at least one fluorine group And / or an olefinically unsaturated monomer having at least one fluorine group and one ethylenically unsaturated bond, and (iv) an alkylene group containing at least one fluorine group and 2 A solid polymer electrolyte membrane, which is at least one selected from the group consisting of diene unsaturated monomers having one ethylenically unsaturated bond. The solid polymer electrolyte membrane according to claim 1, wherein R _{1 in} (a) is H or CH ₃ and R ₂ is H, CH ₃ or CH ₂ Cl. . The solid polymer electrolyte membrane according to claim 1 or 2, wherein the fluorine group-containing (meth) acrylic acid ester has the following general formula (7):

(Wherein X ₃ is a hydrogen group, a fluorine group, a methyl group having or not having at least one fluorine group, and R ₂₅ is an alkyl group having or not having at least one fluorine group). The fluorine group-containing (meth) acrylic acid has the following general formula (8):

Wherein X ₄ is a fluorine group or a methyl group having at least one fluorine group, and the fluorine group-containing olefinically unsaturated monomer is represented by the following general formula (9):

(Where Rf ₁ is an alkyl group containing at least one fluorine group, and X ₅ , X ₆ and X ₇ are each independently a hydrogen group or a fluorine group) or the following general formula (10):

(However, X ₈ , X ₉ and X ₁₀ are each independently a fluorine group or a methyl group having at least one fluorine group, and X ₁₁ is a hydrogen group, a fluorine group, other halogens, or at least one fluorine group. Having a methyl group, an alkyl group having no fluorine group, or an alkoxy group having or not having a fluorine group.), The fluorine group-containing diene unsaturated monomer is represented by the following general formula (11):

(Wherein Rf ₂ is an alkylene group containing at least one fluorine group, and X ₁₂ , X ₁₃ , X ₁₄ , X ₁₅ , X ₁₆ and X ₁₇ are each independently a hydrogen group or a fluorine group). A solid polymer electrolyte membrane characterized by being represented. The solid polymer electrolyte membrane according to any one of claims 1 to 3, wherein (c) is copolymerized with 2,2,2-trifluoroethyl methacrylate. The solid polymer electrolyte membrane according to any one of claims 1 to 4, comprising an unsaturated monomer (d) other than (a) to (c) as a copolymerization component, wherein (d) is 1 in the molecule. Unsaturated monomer (d-1) having at least one ethylenically unsaturated bond and a functional group, and unsaturated monomer having at least one ethylenically unsaturated bond but no functional group in the molecule Or (d-1) having at least one functional group selected from the group consisting of a phosphoric acid residue, a sulfonic acid group, a carboxylic acid group, and an alcoholic hydroxyl group. (D-2) is at least one selected from the group consisting of (meth) acrylonitrile, (meth) acrylic acid esters, (meth) acrylic acid amides, substituted or unsubstituted styrenes and vinyls. A solid polymer electrolyte membrane characterized by that. 6. The solid polymer electrolyte membrane according to claim 5, wherein a weight ratio of (the quaternary ammonium salt-containing monomer composition) / (total of (c) and (d)) is 80/20 to 40/60. solid polymer electrolyte membrane, characterized in that.
(A) A phosphate group-containing unsaturated monomer (a) having a phosphate group and an ethylenically unsaturated bond, and a substituted or unsubstituted amino group and an amino group-containing unsaturated monomer having an ethylenically unsaturated bond The body (b) is reacted in the range where the ratio of the amino group of (b) to the phosphate group of (a) is 50 to 180 mol%, and (a) is modified with (b). A monomer composition comprising a quaternary ammonium salt;
(B) a monomer composition for solid polymer electrolyte comprising at least a fluorine group-containing unsaturated monomer (c),
The quaternary ammonium salt has the following general formula (12):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₃ is a hydrogen group or a methyl group, and R ₄ and R ₅ are each independently hydrogen. Group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, X ₁ is an —O— group or an —NH— group, and Y ₁ is a substituted or unsubstituted carbon atom having 1 to 6 carbon atoms. An alkylene group or an arylene group having 6 to 12 carbon atoms, and n is an integer of 1 to 6.), a compound represented by the following general formula (13):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₆ is a hydrogen group or a methyl group, and R ₇ and R ₈ are each independently hydrogen. A group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, and n is an integer having 1 to 6), the following general formula (14):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₉ is a hydrogen group or a methyl group, and R ₁₀ and R ₁₁ are each independently hydrogen. Group, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and Y ₂ is a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted carbon group having 6 to 16 carbon atoms. An arylene group, and n is an integer of 1 to 6.), a compound represented by the following general formula (15):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₁₂ is a hydrogen group or a methyl group, and R ₁₃ and R ₁₄ are each independently hydrogen. A group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, and n is an integer of 1 to 6), the following general formula (16):

(However, R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, R ₁₅ and R ₁₆ are each independently a hydrogen group or a methyl group, and R ₁₇ is a hydrogen group. Group, an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 10 carbon atoms, and Y ₃ and Y ₄ are each independently a substituted or unsubstituted alkylene group having 1 to 6 carbon atoms or a substituted or unsubstituted group. A compound having 6 to 16 carbon atoms and n is an integer of 1 to 6), and the following general formula (1):

(Wherein R ₁ is a hydrogen group or an alkyl group, R ₂ is a hydrogen group or a substituted or unsubstituted alkyl group, and n is an integer of 1 to 6). The monomer is at least one selected from the group consisting of compounds modified with a heterocyclic amine having one or more vinyl groups,
(c) is (i) (meth) acrylic acid ester having at least one fluorine group, (ii) (meth) acrylic acid having at least one fluorine group, (iii) at least one fluorine group And / or an olefinically unsaturated monomer having at least one fluorine group and one ethylenically unsaturated bond, and (iv) an alkylene group containing at least one fluorine group and 2 A monomer composition for a solid polymer electrolyte, which is at least one selected from the group consisting of diene unsaturated monomers having one ethylenically unsaturated bond. The monomer composition for a solid polymer electrolyte according to claim 7 , wherein all of the hydroxyl groups in the phosphate groups of unreacted (a), unreacted (b), and (a) are (b). A monomer composition for a solid polymer electrolyte, comprising at least one selected from the group consisting of unsaturated monomers reacted with an amino group.
A fuel cell comprising the solid polymer electrolyte membrane according to any one of claims 1 to 6 .

Images