JP2006012784A - Addition reaction curing type silicone rubber adhesive composition for solid polymer fuel cell and solid polymer fuel cell using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an addition reaction curing type silicone rubber adhesive composition for a solid polymer fuel cell in which adhesive force can be maintained for a long period even under a severe condition such as exposure to hot water. <P>SOLUTION: This is the addition reaction curing type silicone rubber adhesive composition for the solid polymer fuel cell comprised by containing (A) an isocyanurate compound, (B) organopolysiloxane containing at least two alkenyl groups bonded to a silicon atom, (C) organohydrogen polysiloxane containing at least two SiH groups, (D) a platinum group metal based catalyst, (E) organopolysiloxane resin having a SiO<SB>4/2</SB>unit and an R<SP>4</SP><SB>3</SB>SiO<SB>1/2</SB>unit (R<SP>4</SP>is independently a non-substituted or substituted monovalent hydrocarbon group which does not contain an aliphatic unsaturated bond or an alkenyl group), and (F) an organic silicon compound having the SiH group, and having an alkoxyl group bonded to a silicon atom and/or an oxilane group containing organic group bonded to the silicon atom. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an addition reaction curable silicone rubber adhesive composition having self-adhesiveness to a solid electrolyte membrane used in a polymer electrolyte fuel cell, and a polymer electrolyte fuel cell using the same.

Development of polymer electrolyte fuel cells is progressing rapidly. The most important components constituting the fuel cell are a solid electrolyte membrane and a separator, and it is essential to bond them. However, since this solid electrolyte membrane contains a polymer having a perfluoroalkylene group represented by the general formula “— (CF ₂ ) _n —” as a main chain, it is very difficult to bond with a conventional adhesive. It was difficult. Moreover, even if it was able to adhere | attach, there existed a problem that a to-be-adhered body peeled with time under the severe conditions exposed to the hot water of about 80-90 degreeC for a long time even if it was able to adhere | attach.

  Conventionally, one molecule has a fluoroalkyl group and / or a fluoroalkyl ether group bonded to a silicon atom via a carbon atom directly bonded to the silicon atom, and bonded to the silicon atom via a carbon atom directly bonded to the silicon atom. Patent Document 1 describes that an addition reaction curable silicone rubber composition containing an organosilicon compound having an epoxy group and / or a trialkoxysilyl group is used as an adhesive in a polymer electrolyte fuel cell. .

JP 2003-7314 A

  An object of the present invention is to provide an addition reaction curable silicone rubber adhesive composition for a polymer electrolyte fuel cell capable of maintaining adhesive force even under severe conditions exposed to hot water for a long time, and a solid using the same It is to provide a polymer fuel cell.

As a means for solving the above problems, the present invention provides:
(A) The following general formula (1):

（１）

（式中、Ｖｉはビニル基を表し、R¹は独立に単結合または炭素原子数１〜１０の直鎖状もしくは分岐状のアルキレン基を表し、R²は独立に水素原子または炭素原子数１〜１０の直鎖状もしくは分岐状のアルキル基を表し、xは0〜3の整数を表し、yは0〜3の整数を表し、ただし、x+yは３である。）で表されるイソシアヌレート化合物、
（Ｂ）ケイ素原子に結合したアルケニル基を少なくとも二個含有するオルガノポリシロキサン、
（Ｃ）ケイ素原子に結合した水素原子を少なくとも二個含有するオルガノハイドロジェンポリシロキサン、
（Ｄ）白金族金属系触媒、
（Ｅ）SiO_4/2で示されるシロキサン単位とR⁴ ₃SiO_1/2（R⁴は独立に、脂肪族不飽和結合を含有しない非置換もしくは置換の一価炭化水素基またはアルケニル基を表す。）で示されるシロキサン単位とを有するオルガノポリシロキサンレジン、および
（Ｆ）ケイ素原子に結合した水素原子を有し、かつケイ素原子に結合したアルコキシ基および／またはケイ素原子に結合したオキシラン基含有有機基を有する有機ケイ素化合物
を含んでなる固体高分子型燃料電池用付加反応硬化型シリコーンゴム接着剤組成物を提供する。
また、本発明は、固体電解質膜とセパレータとがこのシリコーンゴム接着剤組成物で接着されていることを特徴とする固体高分子型燃料電池を提供する。

(1)

(In the formula, Vi represents a vinyl group, R ¹ independently represents a single bond or a linear or branched alkylene group having 1 to 10 carbon atoms, and R ² independently represents a hydrogen atom or 1 carbon atom. -10 represents a linear or branched alkyl group, x represents an integer of 0 to 3, y represents an integer of 0 to 3, provided that x + y is 3. Isocyanurate compounds,
(B) an organopolysiloxane containing at least two alkenyl groups bonded to silicon atoms,
(C) an organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms,
(D) a platinum group metal catalyst,
(E) A siloxane unit represented by SiO _4/2 and R ⁴ ₃ SiO _1/2 (R ⁴ independently represents an unsubstituted or substituted monovalent hydrocarbon group or alkenyl group not containing an aliphatic unsaturated bond. And (F) an organic group having a hydrogen atom bonded to a silicon atom and having an alkoxy group bonded to the silicon atom and / or an oxirane group bonded to the silicon atom. Provided is an addition reaction curable silicone rubber adhesive composition for a polymer electrolyte fuel cell comprising an organosilicon compound having a group.
The present invention also provides a polymer electrolyte fuel cell, characterized in that a solid electrolyte membrane and a separator are bonded with this silicone rubber adhesive composition.

  The solid polymer fuel cell adhesive of the present invention exhibits good self-adhesion with respect to a solid electrolyte membrane containing a polymer having a perfluoroalkylene group as a main chain, and as can be seen from the results of the durability test, Stable adhesiveness can be maintained even under severe conditions such as long-term use in a hot water environment. Further, since the base of the adhesive is an addition reaction curable silicone rubber composition, the cured product of this composition has elasticity and is also effective as a sealing material between the solid electrolyte membrane and the electrode. Therefore, it can greatly contribute to the spread of solid polymer fuel cells in the near future.

  Hereinafter, the present invention will be described in more detail.

[(A) component]
The component (A) is represented by the following general formula (1):

（１）

（式中、Ｖｉはビニル基を表し、R¹は独立に単結合または炭素原子数１〜１０、好ましくは１〜５の直鎖状もしくは分岐状のアルキレン基を表し、R²は独立に水素原子または炭素原子数１〜１０、好ましくは１〜４の直鎖状もしくは分岐状のアルキル基を表し、xは0〜3の整数を表し、yは0〜3の整数を表し、ただし、x+yは３である。）で表されるイソシアヌレート化合物である。この（Ａ）成分を本発明のシリコーンゴム接着剤組成物に添加することで、該シリコーンゴム接着剤組成物の固体電解質膜への接着力が格段に向上し、長時間、熱水にさらされる過酷な条件下でも接着力を維持することができるようになる。

(1)

(In the formula, Vi represents a vinyl group, R ¹ independently represents a single bond or a linear or branched alkylene group having 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms, and R ² independently represents hydrogen. Represents a linear or branched alkyl group having 1 to 10 atoms, preferably 1 to 4 carbon atoms, x represents an integer of 0 to 3, and y represents an integer of 0 to 3, provided that x + y is 3.) isocyanurate compound represented by By adding this component (A) to the silicone rubber adhesive composition of the present invention, the adhesive strength of the silicone rubber adhesive composition to the solid electrolyte membrane is significantly improved and exposed to hot water for a long time. The adhesive force can be maintained even under severe conditions.

When R ¹ is an alkylene group, examples thereof include an ethylene group, a propylene group (trimethylene group), a butylene group (tetramethylene group), a methylethylene group, and a hexamethylene group.

When R ² is an alkyl group, examples thereof include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, heptyl group, An octyl group, a nonyl group, a decyl group, etc. are mentioned.

  Specific examples of the component (A) include the following compounds.

  The component (A) can be used alone or in combination of two or more.

  The addition amount of the component (A) is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 1 part by mass with respect to 100 parts by mass of the component (B). When the addition amount is within this range, the adhesive strength of the silicone rubber adhesive composition to the solid electrolyte membrane can be sufficiently obtained, and the adhesive strength can be maintained for a sufficiently long time.

[Component (B)]
Component (B) is an organopolysiloxane containing at least two alkenyl groups bonded to silicon atoms. The organopolysiloxane of component (B) may be linear or cyclic, and in either case, it may contain a branched structure in the molecule. From the viewpoint of physical properties such as mechanical strength of the cured product, it is preferably substantially linear, and specifically, it is a linear diorganopolysiloxane mainly composed of diorganosiloxane units. It is preferable. The position of the alkenyl group is not particularly limited. When the component (B) is linear, the alkenyl group may be present only at one of the terminal and non-terminal portions of the molecular chain, or may be present at both. Usually, both ends of the linear diorganopolysiloxane are blocked with triorganosiloxy groups.

As a preferable example of the component (B), the following general formula (2):
R ⁴ -Si (R ³ ) ₂ O- [Si (R ³ ) ₂ O] _n- [Si (R ³ ) (X) O] _m -Si (R ³ ) ₂ -R ⁴ (2)
(In the formula, R ³ independently represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, which does not contain an aliphatic unsaturated bond. , X preferably represents an alkenyl group having 2 to 8 carbon atoms, more preferably 2 to 5 carbon atoms, R ⁴ independently represents R ³ or X, n represents an integer of 0 or more, and m represents Represents an integer of 0 or more and the number of silicon-bonded alkenyl groups in the molecule is 2 or more, provided that n + m is preferably an integer of 10 to 10,000, more preferably 50 to 2,000, and , M / (n + m) is preferably a number from 0 to 0.2, where the value of m is specifically an integer of 1 or more when one of R ⁴ is R ³ and the other is X. when both R ⁴ is R ^3, 2 or more integers.) diorganopolysiloxane represented by And the like.

Examples of R ³ include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, and decyl. Group, alkyl group such as dodecyl group; cycloalkyl group such as cyclopentyl group, cyclohexyl group, cycloheptyl group; aryl group such as phenyl group, tolyl group, xylyl group, naphthyl group, biphenylyl group; benzyl group, phenylethyl group, Aralkyl groups such as phenylpropyl group and methylbenzyl group; and groups in which one or more hydrogen atoms of these hydrocarbon groups are substituted with halogen atoms such as fluorine atom, chlorine atom or bromine atom, cyano group, etc. Methyl group, 2-bromoethyl group, 3-chloropropyl group, 3,3,3-trifluoro Propyl group, chlorophenyl group, fluorophenyl group, a cyanoethyl group, 3,3,4,4,5,5,6,6,6 etc. nonafluorohexyl group. Among them, unsubstituted or substituted alkyl groups having 1 to 3 carbon atoms such as methyl group, ethyl group, propyl group, chloromethyl group, bromoethyl group, 3,3,3-trifluoropropyl group, cyanoethyl group, and phenyl group An unsubstituted or substituted phenyl group such as a chlorophenyl group and a fluorophenyl group is particularly preferred.

  Examples of X include a vinyl group, an allyl group, a propenyl group, an isopropenyl group, a butenyl group, a hexenyl group, and a cyclohexenyl group. Among them, a lower alkenyl group such as a vinyl group and an allyl group is particularly preferable.

Preferably the viscosity at 25 ° C. of the alkenyl group-containing organopolysiloxane of the component (B) is a 10~1,000,000mm ² / sec, more preferably 100~500,000mm ² / sec.

[Component (C)]
The component (C) has at least two hydrogen atoms (ie, SiH groups) bonded to silicon atoms (usually about 2 to 150), preferably 3 or more (usually 3 to 100, especially 3 to 60). Organohydrogenpolysiloxane contained. The (C) component reacts with an alkenyl group in the composition, particularly an alkenyl group bonded to a silicon atom in the (B) component in the presence of the platinum group metal catalyst of the (D) component to be described later. Acts as a cross-linking agent to give the original network structure. The molecular structure of component (C) is not particularly limited, and may be any of linear, branched, cyclic and network. Further, an organohydrogenpolysiloxane having a number of silicon atoms (or degree of polymerization) in one molecule of usually 2 to 300, particularly about 4 to 150, can be preferably used as the component (C).

Examples of such a component (C) include the following average composition formula (3):
H _a R ⁵ _b SiO _{(4-ab) / 2} (3)
(Wherein R ⁵ independently represents an unsubstituted or substituted monovalent hydrocarbon group having 1 to 10 carbon atoms, more preferably 1 to 7 carbon atoms, which does not contain an aliphatic unsaturated bond. , A and b are numbers satisfying 0 <a <2, 0.8 ≦ b ≦ 2 and 0.8 <a + b ≦ 3, preferably satisfying 0.05 ≦ a ≦ 1, 0.9 ≦ b ≦ 2 and 1 ≦ a + b ≦ 2.7 And an organohydrogenpolysiloxane represented by the following formula:

In the formula, examples of R ⁵ include the monovalent hydrocarbon groups exemplified for R ^{3 in the} general formula (2). Among these, a lower alkyl group having 1 to 3 carbon atoms such as a methyl group, a phenyl group, and a 3,3,3-trifluoropropyl group are particularly preferable.

Specific examples of the component (C) include 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethyltetracyclosiloxane, 1,3,5,7,8-pentamethylpenta Siloxane oligomers such as cyclosiloxane; molecular chain both ends trimethylsiloxy group blocked methylhydrogen polysiloxane, molecular chain both ends trimethylsiloxy group blocked dimethylsiloxane / methylhydrogensiloxane copolymer, molecular chain both ends silanol group blocked methylhydrogen Polysiloxane, Silanol group-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, Molecular chain both ends dimethylhydrogensiloxy group-blocked dimethylpolysiloxane, Molecular chain both ends dimethylhydrogensiloxy group-blocked methylhydrogenpolysiloxane , Both ends of the molecular chain Mud siloxy group dimethylsiloxane-methylhydrogensiloxane copolymers; and a R ⁵ ₂ (H) SiO _1/2 units and SiO _4/2 units, further R ⁵ ₃ SiO _1/2 units, R ⁵ Silicone resin having a three-dimensional network structure which may contain ₂ SiO _2/2 units, R ⁵ (H) SiO _2/2 units, (H) SiO _3/2 units or R ⁵ SiO _3/2 units (wherein , R ⁵ is the same as above, and the like.

The organohydrogenpolysiloxane of component (C) can be obtained by a known method. For example, by cohydrolyzing at least one chlorosilane selected from the general formulas: R ⁵ SiHCl ₂ and R ⁵ ₂ SiHCl (wherein R ⁵ is as defined above), or the chlorosilane and the general formula: It can be obtained by combining and cohydrolyzing at least one chlorosilane selected from R ⁵ ₃ SiCl and R ⁵ ₂ SiCl ₂ (wherein R ⁵ is the same as above). Further, the component (C) may be one obtained by equilibrating the polysiloxane obtained by cohydrolysis.

  The amount of component (B) and component (C) used is usually the amount of hydrogen atoms bonded to silicon atoms in component (C) (i.e., SiH groups) per mole of alkenyl groups in the total composition. The amount is 0.5 to 4 mol, preferably 1 to 2.5 mol. At this time, the ratio of the alkenyl group in the component (B) to the alkenyl group present in the entire composition is preferably 70 mol% or more, particularly preferably 80 mol% or more. When only the component (B) is present as a component having an alkenyl group in the composition, a hydrogen atom bonded to a silicon atom in the component (C) per mole of the alkenyl group in the component (B) (that is, SiH The amount of the group) is usually 0.5 to 4 mol, preferably 1 to 2.5 mol. When the amount of hydrogen atoms bonded to silicon atoms is within this range, the composition is likely to be sufficiently cured, and a cured product having a required strength is easily obtained. In addition, it is difficult for the composition to foam during curing or to change the physical properties of the cured product over time.

[(D) component]
The platinum group metal catalyst of component (D) has an action of promoting an addition reaction (hydrosilylation reaction) between an alkenyl group in component (B) and a hydrogen atom bonded to a silicon atom in component (C). Have. As the component (D), conventionally known hydrosilylation reaction catalysts can be used. Specific examples thereof include platinum group metals such as platinum (including platinum black), rhodium and palladium; H ₂ PtCl ₄ · nH ₂ O, H ₂ PtCl ₆ · nH ₂ O, NaHPtCl ₆ · nH ₂ O, KHPtCl _{6 · nH 2 O, Na 2 PtCl} 6 · nH 2 O, K 2 PtCl 4 · nH 2 O, PtCl 4 · nH 2 O, PtCl 2, Na 2 HPtCl 4 · nH 2 O ( wherein, n 0-6 Chloroplatinic acid, chloroplatinic acid and chloroplatinic acid salt; alcohol-modified chloroplatinic acid (see US Pat. No. 3,220,972); chloroplatinic acid and olefin Complex (see US Pat. Nos. 3,159,601, 3,159,662, and 3,775,452); a platinum group metal such as platinum black and palladium is supported on a carrier such as alumina, silica and carbon Rogiu Chlorotris (triphenylphosphine) rhodium (Wilkinson catalyst); platinum chloride, chloroplatinic acid or chloroplatinate and a vinyl group-containing siloxane, in particular a vinyl group-containing cyclic siloxane.

  The amount of component (D) added may be an effective amount as a hydrosilylation reaction catalyst, but can be appropriately increased or decreased depending on the desired curing rate. Usually, it is an amount that falls within the range of 0.1 to 1000 ppm, preferably 0.1 to 500 ppm, more preferably 0.5 to 200 ppm on a mass basis in terms of platinum group metal element with respect to the total amount of component (B) and component (C). .

[(E) component]
The component (E) essentially contains a siloxane unit represented by SiO _4/2 and a siloxane unit represented by R ⁴ ₃ SiO _1/2 (R ⁴ is the same as described above), and further R ⁴ ₂ It is an organopolysiloxane resin having a three-dimensional network structure which may optionally contain SiO _2/2 units and R ⁴ SiO _3/2 units. By adding the component (E), the strength of the silicone rubber obtained from the composition of the present invention can be increased. The component (E) preferably further has a siloxane unit containing an alkenyl group bonded to a silicon atom, and the alkenyl group is more preferably a vinyl group. (E) component which has a siloxane unit containing the alkenyl group couple | bonded with the silicon atom can further improve the intensity | strength by being taken in into the crosslinked structure of the silicone rubber obtained from the composition of this invention.

Examples of the component (E) include a resin comprising (CH ₃ ) ₃ SiO _1/2 units, (CH ₂ ═CH) (CH ₃ ) ₂ SiO _1/2 units, and SiO _4/2 units, (CH ₃ ) Resin consisting of ₃ SiO _1/2 units and SiO _4/2 units, Resin consisting of (CH ₃ ) ₃ SiO _1/2 units, (CH ₂ ═CH) SiO _3/2 units and SiO _4/2 units , (CH ₂ = CH) (CH ₃ ) ₂ SiO _1/2 units and a resin composed of SiO _4/2 units, (CH ₂ = CH) (CH ₃ ) ₂ SiO _1/2 units and (CH ₂ = CH ) _Resins composed of SiO _3/2 units and SiO _4/2 units.

  The amount of the component (E) added is not particularly limited as long as the strength of the silicone rubber obtained from the composition of the present invention can be sufficiently secured, and is preferably 1 to 50 parts by mass, for example, per 100 parts by mass of the component (B). Is 2 to 20 parts by mass.

[(F) component]
The component (F) has at least one hydrogen atom (SiH group) bonded to a silicon atom (usually 1 to 20, preferably 2 to 10) and has an alkoxy group bonded to the silicon atom and / or An organopolysiloxane (oligomer) having a linear or cyclic siloxane structure having an organic group containing an oxirane group bonded to a silicon atom, usually having 2 to 30 silicon atoms, preferably about 4 to 20 silicon atoms It is an organosilicon compound and acts as an adhesion-imparting agent that imparts self-adhesion to the composition of the present invention.

  Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, and a tert-butoxy group, and the alkoxy group has a siloxane structure (Si—O—Si). ) May be bonded to the silicon atom constituting the siloxane structure, or may be an alkoxysilyl group bonded to the silicon atom constituting the siloxane structure via an alkylene group. The oxirane group-containing organic group is a group that bonds an oxirane group to a silicon atom via a hydrocarbon group (which may contain an etheric oxygen atom), and examples thereof include the following groups.

  Specific examples of the component (F) include the following compounds (in the following formula, Me represents a methyl group).

  Component (F) is added in such an amount that the composition of the present invention can obtain good self-adhesiveness with respect to the solid electrolyte membrane. For example, 0.5 to 15 masses per 100 parts by mass of component (B). Parts, preferably 1 to 10 parts by mass, more preferably 2 to 7 parts by mass.

[Other ingredients]
In the composition of the present invention, in addition to the components (A) to (F), if necessary, for example, reinforcing inorganic fillers such as crystalline silica, fumed silica, fumed titanium dioxide, and the like; reinforcing silicone Resin; Non-reinforcing inorganic fillers such as calcium silicate, titanium dioxide, ferric oxide, and carbon black can be added. The amount used of these components is a total, and is not particularly limited as long as the effect of the composition of the present invention is not hindered, and is usually 0 to 200 parts by mass per 100 parts by mass of the total amount of the components (A) to (F). Preferably it is 1-100 mass parts, More preferably, it is 5-100 mass parts.

  In order to improve the compression set, a compound that controls or inhibits the hydrosilylation reaction may be added. Specific examples of such compounds include phosphorus compounds such as triphenylphosphine, tributylphosphine, tributylphosphine oxide, tetramethylenediamine, benzotriazole, dibutylamine, triphenylamine, N, N-dimethylbenzylamine, morpholine. Nitrogen compounds such as phosphorus, sulfur compounds such as thiophenol, dibutyl sulfur, diphenyl sulfur, thioacetic acid, acetylenic compounds such as propargyl alcohol, hydroperoxy compounds such as t-butyl hydroperoxide, diisopropylbenzene, hydroperoxide Further, tin compounds such as dibutyltin dilaurate and dioctyltin malate are conceivable.

[Use of composition]
The composition of the present invention can be cured by heating after being applied to a predetermined substrate depending on the application. The curing conditions of the composition of the present invention vary depending on the amount and are not particularly limited. The curing temperature is preferably 80 to 150 ° C, more preferably 100 to 120 ° C. Usually, it hardens in about 10 to 30 minutes.

  The composition of the present invention is used for bonding a solid electrolyte membrane and a separator in a polymer electrolyte fuel cell. Examples of the solid electrolyte membrane include various ion exchange membranes such as a phenol sulfonic acid membrane, a polystyrene sulfonic acid membrane, and a polytrifluorostyrene sulfonic acid membrane, and a fluorine-containing polymer compound membrane such as a perfluorocarbon sulfonic acid (PFSA) membrane. is made of.

  EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

The following compounds were used in Examples and Comparative Examples.
(A-1) Isocyanurate compound 1:

（Ａ−２）イソシアヌレート化合物２：

(A-2) Isocyanurate compound 2:

（Ａ−３）イソシアヌレート化合物３：

(A-3) Isocyanurate compound 3:

（Ａ−４）イソシアヌレート化合物４：

(A-4) Isocyanurate compound 4:

（Ａ−５）イソシアヌレート化合物５：

(A-5) Isocyanurate compound 5:

（Ｂ）アルケニル基含有ジオルガノポリシロキサン：
Vi(Me)₂Si-(OSiMe₂)_n-OSi(Me)₂Vi
（式中、Ｍｅはメチルであり、Ｖｉはビニル基であり、ｎは該ジオルガノポリシロキサンの２５℃における粘度が10000mm²/secとなる数である）
（Ｃ）オルガノハイドロジェンポリシロキサン：

(B) Alkenyl group-containing diorganopolysiloxane:
Vi (Me) ₂ Si- (OSiMe ₂ ) _n -OSi (Me) ₂ Vi
(In the formula, Me is methyl, Vi is a vinyl group, and n is a number at which the viscosity of the diorganopolysiloxane at 25 ° C. is 10,000 mm ² / sec)
(C) Organohydrogenpolysiloxane:

（Ｄ）白金族金属系触媒：
白金−ジビニルテトラメチルジシロキサン錯体／トルエン溶液（白金元素含有量：0.5質量%）
（Ｅ）オルガノポリシロキサンレジン：
Vi(Me)₂SiO_1/2単位とSiO_4/2単位とからなる三次元網状構造のビニル基含有メチルポリシロキサンレジン
（Ｆ）有機ケイ素化合物：

(D) Platinum group metal catalyst:
Platinum-divinyltetramethyldisiloxane complex / toluene solution (platinum element content: 0.5% by mass)
(E) Organopolysiloxane resin:
Vinyl group-containing methylpolysiloxane resin (F) organosilicon compound having a three-dimensional network structure composed of Vi (Me) ₂ SiO _1/2 units and SiO _4/2 units:

（Ｇ）結晶性シリカ：

（Ｈ）硬化制御剤：
エチニル−シクロヘキサノール／50質量%トルエン溶液

(G) Crystalline silica:

(H) Curing control agent:
Ethynyl-cyclohexanol / 50 mass% toluene solution

  The above components (B), (D), (E), (G) and (H) were mixed according to Table 1. The components (A-1) to (A-5), (C), and (F) were added to the obtained mixture according to Table 1, and further mixed. The obtained mixture was degassed under reduced pressure to obtain an adhesive composition. Using a solid electrolyte membrane made of a perfluorosulfonic acid resin (manufacturer name: DuPont, product name: Naffion), a sample piece used for the adhesion durability test was prepared as follows. An adhesive composition is applied on a carbon substrate (5 cm × 5 cm), and a solid electrolyte membrane (5 cm × 5 cm) is placed thereon. From above, it is pressed with a smooth plate so that the adhesive layer has a certain thickness (about 50 μm). This was put in an oven and heated at 120 ° C. for 10 minutes to cure the adhesive layer. Both the adhesion immediately after curing and the adhesion after immersion in hot water at 95 ° C. for 500 hours were compared.

  The evaluation method is as follows. A cut was made with a cutter knife so that the solid electrolyte membrane of the sample piece had a width of 1 cm. The electrolyte membrane was peeled from the carbon substrate using a peel test apparatus. The interface state at that time was observed. If the adhesive layer between the carbon substrate and the solid electrolyte membrane is coherently broken, it is evaluated that the adhesion is good (○), and if the interface peels between the solid electrolyte membrane and the adhesive layer The adhesiveness was evaluated as poor (x). The results are shown in Table 1.

（注）各成分の添加量を質量部で示す。

(Note) The amount of each component added is expressed in parts by mass.

[Evaluation]
From the results of Comparative Examples 1 and 2, even if the organic silicon compound of the component (F) is simply added or the amount thereof is increased, the initial adhesion can be obtained after being immersed in hot water at 95 ° C. It was found that adhesion could not be obtained. On the other hand, from the results of Examples 1 to 8, by adding the isocyanurate compound of component (A), sufficient adhesion can be maintained not only in the initial stage but also after being immersed in hot water at 95 ° C. confirmed.

Claims (3)

(A) The following general formula (1):

(1)

(In the formula, Vi represents a vinyl group, R ¹ independently represents a single bond or a linear or branched alkylene group having 1 to 10 carbon atoms, and R ² independently represents a hydrogen atom or 1 carbon atom. -10 represents a linear or branched alkyl group, x represents an integer of 0 to 3, y represents an integer of 0 to 3, provided that x + y is 3. Isocyanurate compounds,
(B) an organopolysiloxane containing at least two alkenyl groups bonded to silicon atoms,
(C) an organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms,
(D) a platinum group metal catalyst,
(E) A siloxane unit represented by SiO _4/2 and R ⁴ ₃ SiO _1/2 (R ⁴ independently represents an unsubstituted or substituted monovalent hydrocarbon group or alkenyl group not containing an aliphatic unsaturated bond. And (F) an organic group having a hydrogen atom bonded to a silicon atom and an alkoxy group bonded to the silicon atom and / or an oxirane group bonded to the silicon atom. An addition reaction curable silicone rubber adhesive composition for a polymer electrolyte fuel cell, comprising an organosilicon compound having a group.   The composition according to claim 1, wherein the organopolysiloxane of component (B) is a substantially linear organopolysiloxane containing at least two alkenyl groups bonded to silicon atoms.   A solid polymer fuel cell, wherein the solid electrolyte membrane and the separator are bonded together with the silicone rubber adhesive composition according to claim 1.