WO2021181316A1

WO2021181316A1 - Resin composition for electrolyte membrane adhesion, resin film for electrolyte membrane adhesion, and method for producing resin film for electrolyte membrane adhesion

Info

Publication number: WO2021181316A1
Application number: PCT/IB2021/052013
Authority: WO
Inventors: 武井邦浩; 丸山悠以子; 竹山俊輔
Original assignee: 藤森工業株式会社
Priority date: 2020-03-12
Filing date: 2021-03-11
Publication date: 2021-09-16
Also published as: TW202140726A; CN115280559A; JP2021144877A; JP7333766B2

Abstract

The present invention provides a resin composition for electrolyte membrane adhesion which can be adhered in a short period of time and is not susceptible to degradation by water, a resin film for electrolyte membrane adhesion, and a method for producing a resin film for electrolyte membrane adhesion. More specifically, the present invention provides a resin composition for electrolyte membrane adhesion which can be used in the adhesion of an electrolyte membrane, said resin composition containing, as essential components, an acid-modified polyolefin resin (A) and a resin compound (B) that has two or more functional groups corresponding to the functional groups of the electrolyte membrane in each molecule and has four or more functional groups that correspond to the functional groups of the acid-modified polyolefin resin (A) in each molecule, wherein the resin composition (B) has either epoxy groups and hydroxy groups or only epoxy groups as the functional groups.

Description

A method for producing a resin composition for adhering an electrolyte membrane, a resin film for adhering an electrolyte membrane, and a resin film for adhering an electrolyte membrane.

The present invention relates to a resin composition for adhering an electrolyte membrane, a resin film for adhering an electrolyte membrane, and a method for producing a resin film for adhering an electrolyte membrane.

In Reference 1, a reinforcing sheet in contact with an electrolyte membrane-catalyst layer of a fuel cell is composed of an adhesive layer and an elastic layer, and the adhesive layer includes an epoxy resin, an acrylic resin, a urethane resin, a silicone resin, and a solid polymer electrolyte. It is described that at least one selected from the group consisting of ionomer resins is used. In the reinforcing sheet described in Cited Document 1, an elastic layer made of a specific type of rubber is laminated in order to follow the expansion and contraction of the electrolyte membrane and suppress the breakage of the electrolyte membrane. In the adhesive layer described in Reference 1, an adhesive such as Nafion (registered trademark) ionomer, epoxy resin, or acrylic resin, which is a solid electrolyte, is dispersed in a solvent such as an organic solvent or water, and an adhesive solution is applied by coating. , The film is formed by a method of drying the solvent.

Japanese Patent No. 5720810

The electrolyte membrane is deformed by the differential pressure between the anode and cathode of the gas supplied during power generation of the fuel cell. In order to prevent deformation and breakage of the electrolyte membrane, a frame-shaped reinforcing material may be used for the electrolyte membrane, and adhesion between the reinforcing material and the electrolyte membrane is required. As described in Cited Document 1, when a liquid adhesive is applied in a frame shape, dried and cured by heat, and fixed to an electrolyte membrane, the adhesive coating and curing tact is long and productivity is high. There was a problem with. In addition, there is a problem that the adhesive deteriorates due to heat and water generated during power generation, and gas leaks.

The present invention has been made in view of the above circumstances, and is capable of adhering in a short time and is not easily deteriorated by water. The resin composition for adhering an electrolyte membrane, the resin film for adhering an electrolyte membrane, and the resin for adhering an electrolyte membrane. An object of the present invention is to provide a method for producing a film.

In order to solve the above problems, the present invention is a resin composition for adhering an electrolyte membrane used for adhering an electrolyte membrane, which is a functional group that reacts with an acid-modified polyolefin resin (A) and a functional group of the electrolyte membrane. The resin compound (B) having two or more in one molecule and having four or more functional groups in one molecule that react with the acid functional group of the acid-modified polyolefin resin (A) is an essential component. Provided is a resin composition for adhering to an electrolyte film, wherein the resin compound (B) has only an epoxy group and a hydroxyl group or an epoxy group as a functional group.

The resin composition for adhering to an electrolyte film is a graft copolymer (G) obtained by graft-polymerizing the acid functional group of the acid-modified polyolefin resin (A) and the functional group of the resin compound (B). May be contained.
The resin compound (B) may be contained in the range of 1 to 25 parts by weight in 100 parts by weight of the solid content of the resin composition for bonding the electrolyte membrane.
The resin-based compound (B) may be an epoxy resin or a phenoxy resin.
The thermoplastic elastomer resin (C) may be contained in the range of 1 to 15 parts by weight in 100 parts by weight of the solid content of the resin composition for bonding the electrolyte membrane.

The present invention also provides a resin film for bonding an electrolyte film, wherein the resin composition for bonding an electrolyte film is formed into a film.
The present invention also provides a resin film for bonding an electrolyte film, wherein the adhesive layer formed from the resin composition for bonding an electrolyte film is laminated on at least one surface of a base material layer.

The present invention also provides a method for producing a resin film for bonding an electrolyte film, which comprises melt-kneading the resin composition for bonding an electrolyte film and forming a film into a film by extrusion molding.
The present invention also provides a method for producing a resin film for bonding an electrolyte membrane, which comprises dissolving the resin composition for bonding an electrolyte membrane in a solvent and applying the composition.

According to the present invention, it is possible to provide a resin composition for adhering an electrolyte membrane, a resin film for adhering an electrolyte membrane, and a method for producing a resin film for adhering an electrolyte membrane, which can be adhered in a short time and are not easily deteriorated by water. can.

It is sectional drawing which shows an example of the adhesive film which does not have a base material layer. It is sectional drawing which shows an example of the adhesive film which has a base material layer.

Hereinafter, the present invention will be described based on preferred embodiments.
The adhesive resin composition according to the embodiment of the present invention has the acid-modified polyolefin resin (A) and two or more functional groups that react with the functional groups of the electrolyte membrane in one molecule, and the acid-modified polyolefin resin (A). A resin compound (B) having four or more functional groups that react with the acid functional group of A) in one molecule is contained as an essential component. Further, the adhesive resin composition according to the embodiment of the present invention can be used for adhering the electrolyte membrane.

[Acid-modified polyolefin resin (A)]
The acid-modified polyolefin resin (A) used in the adhesive resin composition is a polyolefin-based resin modified with an unsaturated carboxylic acid or a derivative thereof, and has a carboxyl group or an anhydrous carboxylic acid group in the polyolefin-based resin. Preferably, the polyolefin-based resin is modified with an unsaturated carboxylic acid or a derivative thereof. Acid modification methods for acid-modified polyolefin resins include graft modification such as melt-kneading an acid functional group-containing monomer with a polyolefin resin in the presence of a radical polymerization initiator such as an organic peroxide or an aliphatic azo compound, or acid functionality. Examples thereof include copolymerization of a group-containing monomer and olefins.

Examples of the polyolefins include polyethylene, polypropylene, poly-1-butene, polyisobutylene, a random copolymer of propylene and ethylene or α-olefin, and a block copolymer of propylene and ethylene or α-olefin. .. Among them, polypropylene-based resins such as homopolypropylene (homo-PP, propylene homopolymer), propylene-ethylene block copolymer (blockPP), and propylene-ethylene random copolymer (random PP) are preferable. In particular, random PP is preferable.
Examples of the olefins in the case of copolymerization include olefin-based monomers such as ethylene, propylene, 1-butene, isobutylene, 1-hexene and α-olefin.

The acid functional group-containing monomer is a compound having an ethylenic double bond and a carboxylic acid group or a carboxylic acid anhydride group in the same molecule, and is a various unsaturated monocarboxylic acid, dicarboxylic acid, or dicarboxylic acid. Consists of acid anhydride of acid.
Examples of the acid functional group-containing monomer having a carboxylic acid group (carboxylic acid group-containing monomer) include acrylic acid, methacrylic acid, maleic acid, nadic acid, fumaric acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, and tetrahydrophthalic acid. , Α, β-unsaturated carboxylic acid monomers such as endo-bicyclo [2.2.1] -5-heptene-2,3-dicarboxylic acid (endic acid).
Examples of the acid functional group-containing monomer having a carboxylic acid anhydride group (carboxylic acid anhydride group-containing monomer) include unsaturated dicarboxylic acids such as maleic anhydride, nadicic anhydride, itaconic anhydride, citraconic anhydride, and endic acid anhydride. An anhydride monomer can be mentioned.
As these acid functional group-containing monomers, one type may be used in the acid-modified polyolefin resin (A), or two or more types may be used in combination.

Among the acid functional group-containing monomers, a carboxylic acid anhydride group-containing monomer is more preferable, and maleic anhydride is more preferable.
When a part of the acid functional group-containing monomer used for acid modification is unreacted, the acid-modified polyolefin resin is obtained by removing the unreacted acid functional group-containing monomer in order to suppress an adverse effect on the adhesive force. It is preferable to use it as (A).

Regarding the propylene component in the acid-modified polyolefin resin (A), from the viewpoint of heat resistance of the resin, it is preferable that the propylene unit is a majority. The majority amount here means that the propylene component with respect to the acid-modified polyolefin resin (A) is 50% by weight or more. Therefore, as the acid-modified polyolefin resin (A), an acid-modified polypropylene-based resin having a majority of propylene units is preferable.

[Resin-based compound (B)]
The resin compound (B) used in the adhesive resin composition has two or more functional groups in one molecule that react with the functional groups of the electrolyte membrane, and the acid of the acid-modified polyolefin resin (A). It is a compound having 4 or more functional groups in one molecule that react with the functional groups. The resin compound (B) has only an epoxy group and a hydroxyl group, or an epoxy group as a functional group. Examples of the resin compound (B) include an epoxy resin and a phenoxy resin. Further, as a resin having an epoxy group and a hydroxyl group in the functional group of the side chain, or a resin having only an epoxy group, a polymer obtained by polymerizing a monomer having an epoxy group or a copolymer containing a monomer having an epoxy group and a monomer having a hydroxyl group. Can also be used.

The resin compound (B) is contained in one molecule obtained by epoxidation such as glycidylation of a polymer having a plurality of hydroxyl groups, such as polyhydroxypolyester, polyhydroxypolyester, polyhydroxypolyester, and polyhydroxypolyamide. Examples include compounds having two or more epoxy groups. Specific examples thereof include epoxy resins or phenoxy resins synthesized by reacting bisphenols with epichlorohydrin, which are represented by the following general formula (1) and have epoxy groups at both ends. Can be mentioned.

R ^1- O- [R ^2- O-CH ₂ CH (OH) CH _2- O] _p- R ^2- O-R ¹ ... (1)

In the general formula (1), R ¹ represents a glycidyl group (ie, a 2,3-epoxypropyl group). Further, ^{R 2} is a bisphenol _{_{^{^{HO-C 6 H 4 -C (}}}} R 3) (R 4) -C 6 H 4 when represented as _{_{^{-OH, -C 6 H 4 -C (}}} R 3) ( R ^₄₎ _-C 6 _H ⁴ - is a divalent group corresponding to. Examples of the substituents R ³ and R ⁴ of bisphenols include hydrogen atoms or alkyl groups such as methyl groups and ethyl groups, respectively.

Further, in the general formula (1), the integer p is equal to the number of hydroxyl groups (number of hydroxyl groups) that the compound has in one molecule. In this case, the functional groups that react with the acid functional groups of the acid-modified polyolefin resin (A) are p hydroxyl groups and two epoxy groups at both ends. In order to increase the number of functional groups that react with acid functional groups to 4 or more in one molecule, it is preferable that p + 2 ≧ 4.

The phenoxy resin is a bisphenol A (BPA) type phenoxy resin in which ^{the substituents R 3} and R ⁴ of the bisphenols in the general formula (1) are both CH ₃ , and bisphenol F in which both ^{R 3} and R ^{4 are H.} (BPF) type phenoxy resin, bisphenol A type and bisphenol F type copolymerized, BPA / BPF copolymerized phenoxy resin, one of R ³ or R ⁴ is CH ₃ and the other is H. Examples include B-type phenoxy resin. Further, since the bisphenol type epoxy resin is represented by the above general formula (1) like the phenoxy resin, a resin having a relatively high molecular weight and a large number of hydroxyl groups p can be selected and used.

The weight average molecular weight (Mw) of the phenoxy resin or epoxy resin is preferably about 3,000 (in the case of bisphenol A type, the number of hydroxyl groups p is about 10) or more, and for example, about 15,000 (in the case of bisphenol A type, in the case of bisphenol A type). The number of hydroxyl groups p is about 50), about 20,000 (in the case of bisphenol A type, the number of hydroxyl groups p is about 70), and higher molecular weight ones can also be used.
The upper limit of the average molecular weight of the phenoxy resin or the epoxy resin is not particularly limited, but is preferably about 80,000 (in the case of the bisphenol A type, the number of hydroxyl groups p is about 280). When the average molecular weight of the phenoxy resin or epoxy resin is determined by GPC, for example, tetrahydrofuran (THF) is used as the eluent for GPC, and TSKgel G4000H and TSKgel G3000H (both manufactured by Tosoh Corporation) are used as columns. It can be obtained by concatenating the product name).

Specific examples of the phenoxy resin include trade name: YP-50 (Mw: 60,000 to 80,000, BPA type, number of hydroxyl groups p: about 210 to 280) manufactured by Nittetsu Chemical & Materials Co., Ltd., YP- 50S (Mw is 50,000 to 70,000, BPA type, number of hydroxyl groups p is about 175 to 245), YP-55U (Mw is 40,000 to 45,000, BPA type, number of hydroxyl groups p is about 140 to 160) ), YP-70 (Mw is 50,000 to 60,000, BPA / BPF copolymer type), ZX-1356-2 (Mw is 60,000 to 80,000, BPA / BPF copolymer type), FX- 316 (Mw is 40,000 to 60,000, BPF type), etc .; Phenoxy type grade 1256 (molecular weight about 50,000, BPA type), 4250 (molecular weight about 60,000, BPA / BPF copolymer type) manufactured by Mitsubishi Chemical Corporation. ), 4275 (molecular weight about 60,000, BPA / BPF copolymer type), 1255HX30, YX8100BH30, YX6954BH30, etc .; PKHB, PKHC, PKHH, PKHJ, etc. manufactured by Tomoe Kogyo Co., Ltd. can be mentioned.

Specific examples of the epoxy resin include trade names: YD-020G (epoxy equivalent 3500 to 4500, BPA type) manufactured by Nittetsu Chemical & Materials Co., Ltd .; Grade 1010 (average molecular weight 5500) manufactured by Mitsubishi Chemical Co., Ltd. , BPA type, epoxy equivalent 3000 to 5000), 1009 (average molecular weight 3800, BPA type, epoxy equivalent 2400 to 3300) and the like.

Further, examples of the resin compound (B) include compounds in which the functional group that reacts with the acid functional group is only an epoxy group, and the compound has four or more of the epoxy groups in one molecule. Specific examples of such a compound include a phenol novolac epoxy resin synthesized by reacting phenol novolac with epichlorohydrin, and a cresol novolac resin synthesized by reacting O-cresol novolac with epichlorohydrin into a molecular chain. Examples thereof include resin compounds having four or more epoxy groups. As commercially available products of such epoxy resins, for example, as bisphenol A type novolak epoxy resin, trade name: jER157S70 manufactured by Mitsubishi Chemical Co., Ltd., trade name: EPICLON N-865, N-885, trade name of DIC Co., Ltd., As a cresol novolac epoxy resin, the trade name of DIC Co., Ltd .: EPICLON N-670, N-673, N-680, N-690, N-695, as a phenol novolac epoxy resin, the trade name of DIC Co., Ltd .: N-770 , N-775 and the like.

Further, as the resin-based compound (B), in addition to the resin-based compound having four or more epoxy groups in one molecule that react with the acid functional group of the acid-modified polyolefin resin (A), one epoxy group is contained. A resin compound having two or more functional groups in one molecule and reacting with the acid functional group of the acid-modified polyolefin resin (A), the functional groups being an epoxy group and a hydroxyl group. It may be further contained.

In the adhesive resin composition, the acid functional group of the acid-modified polyolefin resin (A) and the functional group (epoxy group, hydroxyl group) of the resin compound (B) function as an adhesive functional group for an adherend. By doing so, it has excellent adhesive strength to the adherend having an electrolyte film. Further, since the acid functional group of the acid-modified polyolefin resin (A) and the functional group (epoxide group, hydroxyl group) of the resin compound (B) easily react with each other by heating, they also react with these functional groups. It is not necessary to add a curing agent or the like to be obtained.

The resin compound (B) is preferably contained in the range of 1 to 25 parts by weight in 100 parts by weight of the solid content of the adhesive resin composition. The affinity of the polyolefin portion of the acid-modified polyolefin resin (A) for a plastic having low polarity and the affinity of the adhesive functional group for a different material such as an electrolyte film have a suitable balance, and the electrolyte film has a suitable balance. In addition to adhering to dissimilar materials such as polyolefin, it also has excellent adhesive strength when adhering to low-polarity plastics such as polyolefin. Specific examples of the ratio of the resin compound (B) to 100 parts by weight of the solid content include, for example, 1 part by weight, 5 parts by weight, 10 parts by weight, 15 parts by weight, 20 parts by weight, 25 parts by weight, or the like. Values near or in between these may be mentioned.

[Graft copolymer (G)]
The adhesive resin composition is a graft obtained by graft-polymerizing the acid functional group of the acid-modified polyolefin resin (A) and the functional group (epoxy group, hydroxyl group) of the resin compound (B). It preferably contains the polymer (G). According to the graft copolymer (G), the acid-modified polyolefin resin (A) and the resin-based compound (B) are graft-polymerized to prevent separation of the two, and an acid functional group and a functional group (epoxy). Due to the synergistic effect with (group, hydroxyl group), it is possible to have excellent adhesive strength.

The graft copolymer (G) preferably has an epoxy group derived from the resin compound (B). In this case, as the graft copolymer (G), the effect of improving the adhesive force by the epoxy group can be obtained together with the acid functional group and the functional group (epoxy group, hydroxyl group). The graft copolymer (G) is obtained by blending the acid-modified polyolefin resin (A) in an amount of 75 to 99% by mass and the resin compound (B) in an amount of 1 to 25% by mass, and graft-polymerizing the mixture. The obtained one is preferable.

The graft copolymer (G) is preferably obtained by melt-grafting polymerizing the acid-modified polyolefin resin (A) and the resin-based compound (B). In this melt graft polymerization, the adhesive resin composition containing the acid-modified polyolefin resin (A) and the resin compound (B) is graft-polymerized in an apparatus by melt-kneading. As the melt-kneading device, a single-screw extruder, a multi-screw extruder, a Banbury mixer, a plast mill, a heating roll kneader, or the like can be used.

In order to suppress the decomposition of the epoxy group in the graft copolymer (G) during the melt graft polymerization, it is desirable to remove and discharge the volatile components that can react with the epoxy group such as water to the outside of the apparatus. .. If volatile components are generated during melt-kneading, it is desirable to discharge them to the outside of the device at any time by degassing or the like. This makes it possible to suppress foaming when forming an adhesive film or an adhesive layer using the adhesive resin composition.

When the acid-modified polyolefin resin (A) has an acid anhydride group as an acid functional group, the resin compound (B) has high reactivity with the functional group (epoxide group, hydroxyl group) and is more mild. It is preferable because graft polymerization is possible underneath.

The heating temperature (kneading temperature) at the time of melt-kneading is within the range of 130 to 300 ° C. in that the acid-modified polyolefin resin (A) and the resin-based compound (B) are sufficiently melted and do not thermally decompose. It is preferable to select from. When the acid-modified polyolefin resin (A) is an acid-modified polypropylene-based resin, the temperature is preferably 180 to 300 ° C., and preferably 240 to 300 ° C. in order to further improve dispersibility. The kneading temperature can be measured by a method such as bringing a thermocouple into contact with the adhesive resin composition in a molten state immediately after being extruded from the melt-kneading apparatus.

[Thermoplastic elastomer resin (C)]
The adhesive resin composition may contain a thermoplastic elastomer resin (C) as an optional component. Examples of the thermoplastic elastomer resin (C) include styrene elastomer, styrene butadiene copolymer, epoxy-modified styrene butadiene copolymer, olefin elastomer, polyester elastomer, styrene butadiene styrene block copolymer, and styrene ethylene propylene styrene block copolymer. , Styrene isoprene butadiene styrene block copolymer, styrene isoprene styrene block copolymer and the like. When the thermoplastic elastomer resin (C) is added, the thermoplastic elastomer resin (C) may be contained in the range of 1 to 15 parts by weight in 100 parts by weight of the solid content of the adhesive resin composition. preferable.

The thermoplastic elastomer resin (C) is melt-kneaded as long as it does not react with the acid-modified polyolefin resin (A) or the resin-based compound (B) under the conditions of melt-kneading of the adhesive resin composition. It can also be blended before. In this case, when the mixture containing the acid-modified polyolefin resin (A), the resin-based compound (B), and the thermoplastic elastomer resin (C) is melt-kneaded, the acid-modified polyolefin resin (A) and the resin are used. The adhesive resin composition containing the graft copolymer (G) can be obtained by selectively reacting with the system compound (B).

[Adhesive resin composition]
The adhesive resin composition contains the acid-modified polyolefin resin (A) and the resin compound (B) as essential components, and the adhesive resin composition is melt-kneaded and extruded (1 step). ), The adhesive layer can be manufactured. When the adhesive layer is formed into a single-layer film, a single-layer adhesive film is obtained. When the adhesive layer is laminated on the base material layer, a multi-layer adhesive film is obtained.

Further, the adhesive layer can be produced by a method in which the adhesive resin composition is dissolved in a solvent and applied. The method for applying the adhesive resin composition is not particularly limited, and the adhesive resin composition can be applied by a conventional method using a known coating device such as a bar coater, a die coater, or a gravure coater. Examples of the object to which the adhesive resin composition is applied include an adherend, a release material (release film or the like) capable of peeling the adhesive layer after application, a base material layer of an adhesive resin laminate described later, and the like.

As the organic solvent used for coating, a compound that does not easily react with the resin component constituting the adhesive resin composition is preferable. For example, a hydrocarbon solvent such as toluene, an ether solvent such as ethylene glycol dimethyl ether, and a ketone such as methyl ethyl ketone are used. Examples thereof include a system solvent and an ester solvent such as ethyl acetate. The drying conditions may be appropriately set according to the organic solvent used. For example, at least a part of the organic solvent can be volatilized by heating at a temperature of 40 to 150 ° C. for 5 to 600 seconds.

The adhesive resin composition has an acid functional group of the acid-modified polyolefin resin (A) and a functional group (epoxide group, hydroxyl group) of the resin compound (B), so that excellent adhesive strength can be obtained. Be done. In particular, excellent adhesive strength can be obtained and low-temperature adhesiveness is improved even in a relatively low temperature region close to the melting point (Tm) of the acid-modified polyolefin resin (A), which is the base resin.

Further, when the acid-modified polyolefin resin (A) and the resin compound (B) are graft-polymerized at the time of melt-kneading the adhesive resin composition, the step of preparing the graft copolymer (G) is performed. There is no need to provide it separately, the productivity is excellent, and damage to the resin component can be suppressed. The adhesive resin composition has excellent adhesive force to an adherend having an electrolyte membrane, has a simple composition, and can easily produce an adhesive layer. Further, in the adhesive resin composition, the main chain of the acid-modified polyolefin resin (A) is composed of addition polymerization of vinyl groups like the polyolefin resin, and is not easily hydrolyzed, so that it is not easily hydrolyzed in a high temperature environment. Has water resistance.

As other additives, a filler, a colorant, an antioxidant, an antifoaming agent, a leveling agent, a light absorber, and the like can be appropriately added to the adhesive resin composition. The adhesive resin composition is other than the essential components of the acid-modified polyolefin resin (A) and the resin-based compound (B) or the graft copolymer (G), and the optional component of the thermoplastic elastomer resin (C). Can be configured without containing a resin component or a polymer component. The proportion of other solids excluding the essential component of the acid-modified polyolefin resin (A) and the resin compound (B) or the graft copolymer (G) and the optional component of the thermoplastic elastomer resin (C) is , 10 parts by weight or less, 5 parts by weight or less, 1 part by weight or the like may be added to 100 parts by weight of the total solid content.

[Subject]
As the electrolyte membrane of the adherend, a solid polymer electrolyte membrane known or commercially available in applications such as fuel cells can be used. For example, a hydrogen ion conductive polymer electrolyte, a perfluorosulfonic acid-based fluorine ion exchange resin, an anionic conductive solid polymer electrolyte membrane, and the like can be mentioned. Perfluorocarbon sulfonic acid-based polymer (PFS-based polymer) is chemically very stable by introducing a fluorine atom having a high electronegativity into the polymer, has a high degree of dissociation of a sulfonic acid group, and has high ionic conductivity. Is preferable because it can be realized. The film thickness of the electrolyte membrane is, for example, about 20 to 250 μm, preferably about 20 to 80 μm.

A catalyst layer such as platinum, a platinum alloy, or a platinum compound may be laminated on the surface of the electrolyte membrane as a cathode catalyst or an anode catalyst. Further, the electrolyte membrane of the adherend may have a reinforcing material or the like. The reinforcing material or the like may be composed of a polyolefin-based resin, an olefin-based elastomer or the like. When the adhesive resin composition is used for bonding between two or more adherends, at least one adherend may have an electrolyte membrane. A part of the adhesive resin composition may be adhered so as to be in contact with the catalyst layer, the reinforcing material, or the like.

When the resin compound (B) has two or more functional groups (epoxy groups, hydroxyl groups) that react with the functional groups of the electrolyte membrane in one molecule, the adhesive resin composition adheres so as to be in contact with the electrolyte membrane. By doing so, a chemical bond between functional groups is formed at the interface, and an adhesive property having excellent water resistance is exhibited. Examples of the functional group of the electrolyte membrane include a sulfonic acid group and a carboxylic acid group.

[Adhesive resin molded product]
The adhesive resin molded body of the embodiment is a molded body formed from the adhesive resin composition and having a shape such as a film or a sheet, and can be used as a single-layer adhesive film or the like. In the adhesive resin molded product, an adhesive resin composition containing the acid-modified polyolefin resin (A) and the resin compound (B) as essential components is melt-kneaded and extruded to obtain a film, sheet or the like. It can be manufactured by a method of molding into a shape (one step). Further, it is possible to produce an adhesive resin molded product by dissolving the adhesive resin composition in a solvent and applying the adhesive resin composition to the adherend or the release material. For example, as shown in FIG. 1, it is possible to adhere to the adherend 21 on at least one side of the single-layer adhesive film 10.

The adhesive resin molded body is laminated with an adherend by, for example, the methods listed in (1) to (4) below, and various adherends are heated, preferably heated and pressurized. It is possible to bond with.
(1) A method of laminating and adhering an adhesive resin molded body on one side of an adherend.
(2) A method of laminating and adhering different adhesive resin molded bodies on both sides of an adherend.
(3) A method of laminating and adhering different adherends to both sides of a resin molded product for adhesion.
(4) A method in which a plurality of resin molded bodies for adhesion and a plurality of adherends are alternately laminated and bonded.

[Adhesive resin laminate]
The adhesive resin laminate according to the embodiment of the present invention is a laminate having an adhesive layer made of the adhesive resin composition on at least one side of the base material layer. As shown in FIG. 2, the multilayer adhesive film 10A has an adhesive layer 11 on one side of the base material layer 12, and can be adhered to the adherend 21 by using the adhesive layer 11. The base material layer does not have to have adhesiveness to the base material layer itself, and is preferably one that can be adhered to the adhesive layer. Further, the base material layer preferably has flexibility capable of following the expansion and contraction of the electrolyte membrane, heat resistance according to the usage conditions of the electrolyte membrane, chemical resistance and the like.

Specific examples of the base material layer include polyolefin resins such as polyethylene resins and polypropylene resins. By using a thin base material layer such as a resin film, the adhesive resin laminate can be used as an adhesive resin film, an adhesive resin sheet, or the like. When the base material layer is required to have water resistance in a high temperature environment, a polyolefin resin is preferable.

In the adhesive resin laminate, an adhesive resin composition containing the acid-modified polyolefin resin (A) and the resin compound (B) as essential components is melt-kneaded, and an adhesive layer is formed by extrusion molding. It can be manufactured by the method (1 step). When the base material layer is made of a thermoplastic resin, extrusion molding of the adhesive resin composition can be performed by a coextrusion method. It is also possible to extrude the adhesive resin composition by an extrusion laminating method. Further, the adhesive resin laminate can be produced by a method of dissolving the adhesive resin composition in a solvent and applying the adhesive resin composition to the base material layer.

When the adhesive resin laminate has the adhesive layer resin layer on only one side of the base material layer, it is laminated with the adherend by, for example, the method described in (1) or (2) above. By heating, preferably by heating and pressurizing, it is possible to adhere to various adherends. When the adhesive layer resin laminate has the adhesive layer resin layers on both sides of the base material layer, the adhesive layer resin laminate is laminated with the adherend by, for example, the methods described in (1) to (4) above. However, it can be adhered to various adherends by heating, preferably by heating and pressurizing.

Although the present invention has been described above based on preferred embodiments, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

Hereinafter, the present invention will be specifically described with reference to Examples.

(Adhesive film)
The adhesive resin compositions of the compositions 1 to 9 shown in Table 1 were blended to produce the adhesive film shown in the layer structure of Table 2.
In the case of no base material layer (compositions 1 to 4, 6, 8, 9), the acid-modified polyolefin resin (A), the resin-based compound (B), and the thermoplastic elastomer resin (C) were mixed at 240 ° C. for 2 minutes. An adhesive film composed of a single adhesive layer was produced by a method of melt-kneading and then molding to a thickness of 150 μm by extrusion molding.

When there is a base material layer (compositions 5 and 7), the acid-modified polyolefin resin (A) and the resin-based compound (B) are dissolved in a mixed solvent of toluene and methyl ethyl ketone (MEK) to prepare an adhesive resin composition. After preparing the coating liquid of, the coating liquid was applied on the corona-treated surface of a polypropylene (PP) film having a thickness of 140 μm by hand coating so that the thickness after drying was 10 μm, and dried at 110 ° C. for 2 minutes. By doing so, a two-layer adhesive film composed of a base material layer and an adhesive layer was produced.

The meanings of the abbreviations used in Table 1 are as follows.
"(A) -1": Maleic acid-modified polypropylene (acid addition 0.1% by mass, melting point 140 ° C.)
"(A) -2": Maleic acid-modified polyolefin (acid addition 1.1% by mass, melting point 80 ° C.)
"(B) -1": Bisphenol A type epoxy (weight average molecular weight 900, 2 hydroxyl groups in 1 molecule, 2 epoxy groups)
"(B) -2": Bisphenol A type novolak type epoxy (weight average molecular weight 900, 2 hydroxyl groups in 1 molecule, 2 epoxy groups)
"(B) -3": Bisphenol A type epoxy (weight average molecular weight 370, 0 hydroxyl groups in 1 molecule, 2 epoxy groups)
"(C) -1": Propylene-α-olefin copolymer elastomer (softening point 70 ° C.)

(Measurement method of adhesive strength)
Using Nafion (registered trademark) NRE-212 (thickness 0.002 inch) as an adherend, it is processed to a size of 50 mm × 50 mm, and the adherend is placed on an adhesive film and heat-bonded from the adherend side to form a test piece. Made. The adhesive strength of the adhesive film to the adherend was measured at a tensile speed of 300 mm / min, a width of 15 mm, and 180 ° peeling. The heat crimping condition is to heat and pressurize at a temperature of 170 ° C. at a pressure of 0.1 MPa for 10 seconds. The case where the adhesive strength was 5N / 15 mm or more was evaluated as "◯", the case where the adhesive strength was 3N / 15 mm or more and less than 5N / 15 mm was evaluated as "Δ", and the case where the adhesive strength was less than 3N / 15 mm was evaluated as "x".

(Evaluation method of water resistance)
The test piece prepared in the same manner as in the method for evaluating the adhesive strength was immersed in water having a water temperature of 90 ° C. for 300 hours, and the adhesive strength was measured. The case where the adhesive strength after immersion in water was 5N / 15 mm or more was evaluated as "◯", the case where it was 3N / 15 mm or more and less than 5N / 15 mm was evaluated as "Δ", and the case where it was less than 3N / 15 mm was evaluated as "x".

The evaluation results of the adhesive film are shown in Table 2. According to the adhesive film using the adhesive resin compositions of the compositions 1 to 5, the adhesive strength is sufficient not only before the immersion in water but also after the immersion in water. The adhesive film using the adhesive resin composition of the compositions 6 to 7 did not have adhesiveness to the electrolyte membrane. The adhesive film using the adhesive resin composition of the compositions 8 to 9 did not have adhesiveness to the electrolyte membrane after being immersed in water.

The present invention has an excellent adhesive force to an adherend having an electrolyte film, has a simple composition, and can be easily produced as an electrolyte film adhesive resin composition and an electrolyte film adhesive resin film. , And because it is possible to provide a method for producing a resin film for adhering an electrolyte film, it has great industrial utility value.

10 ... Single-layer adhesive film, 10A ... Multi-layer adhesive film, 11 ... Adhesive layer, 12 ... Base material layer, 21 ... Adhesive body.

Claims

A resin composition for adhering an electrolyte membrane, which is used for adhering an electrolyte membrane.
An acid-modified polyolefin resin (A) and a functional group having two or more functional groups that react with the functional group of the electrolyte membrane in one molecule and reacting with the acid functional group of the acid-modified polyolefin resin (A). A resin-based compound (B) having 4 or more of these in one molecule is contained as an essential component.
A resin composition for bonding an electrolyte film, wherein the resin compound (B) has only an epoxy group and a hydroxyl group, or an epoxy group as a functional group.
It is characterized by containing a graft copolymer (G) obtained by graft-polymerizing the acid functional group of the acid-modified polyolefin resin (A) and the functional group of the resin compound (B). The resin composition for adhering an electrolyte film according to claim 1.
The invention according to claim 1 or 2, wherein the resin compound (B) is contained in the solid content of 100 parts by weight of the resin composition for adhering the electrolyte film in the range of 1 to 25 parts by weight. Resin composition for bonding electrolyte membrane.
The resin composition for adhering to an electrolyte membrane according to any one of claims 1 to 3, wherein the resin compound (B) is an epoxy resin or a phenoxy resin.
Any of claims 1 to 4, wherein the thermoplastic elastomer resin (C) is contained in the solid content of 100 parts by weight of the resin composition for bonding the electrolyte film within the range of 1 to 15 parts by weight. The resin composition for adhering an electrolyte membrane according to item 1.
A resin film for bonding an electrolyte membrane, wherein the resin composition for bonding an electrolyte film according to any one of claims 1 to 5 is formed into a film.
An electrolyte membrane adhesive resin formed by laminating an adhesive layer formed from the electrolyte membrane adhesive resin composition according to any one of claims 1 to 5 on at least one surface of a base material layer. the film.
A method for producing a resin film for bonding an electrolyte film, which comprises melt-kneading the resin composition for bonding an electrolyte film according to any one of claims 1 to 5 and forming a film by extrusion molding.
A method for producing an electrolyte membrane adhesive resin film, which comprises dissolving and applying the electrolyte membrane adhesive resin composition according to any one of claims 1 to 5 in a solvent.