JPWO2019181851A1 - Adhesive set and structure manufacturing method - Google Patents

Abstract

In one embodiment, the present invention comprises a first liquid containing a polymerization initiator and a second liquid containing a reducing agent, and at least one of the first liquid and the second liquid has an ethylenically unsaturated group. An adhesive set is provided that further contains a monomer, and at least one of the first liquid and the second liquid further contains a (meth) acrylic elastomer having a weight average molecular weight of 250,000 or more.

Description

The present invention relates to an adhesive set and a method for manufacturing a structure using the adhesive set.

Conventionally, (meth) acrylic adhesives have been used in various fields including the automobile field. Among them, a first liquid and a second liquid are provided, and by mixing these, the temperature is about room temperature (for example, 30 ° C.). ) Curable adhesives (so-called room temperature curable two-component adhesives) have been studied in various ways. As disclosed in Patent Document 1, for example, a rubber component such as polybutadiene may be added to such a two-component (meth) acrylic adhesive.

Japanese Unexamined Patent Publication No. 5-098216

By the way, in the field of automobiles, replacement of steel with lighter materials such as aluminum and carbon fiber reinforced plastic (CFRP) is being studied in order to reduce the weight of automobiles. In this case, it is necessary to bond adherends made of different materials (for example, steel plate and aluminum plate, steel plate and CFRP plate, etc.), but this is done by using a conventional room temperature curable two-component adhesive. Even if such adherends are adhered to each other, sufficient adhesiveness cannot always be obtained.

Therefore, the present invention has been made in view of the above circumstances, and is an adhesive set capable of curing at room temperature, which has excellent adhesiveness to adherends made of different materials, and the adhesive. It is an object of the present invention to provide a method for manufacturing a structure using a set.

One aspect of the present invention includes a first liquid containing a polymerization initiator and a second liquid containing a reducing agent, and at least one of the first liquid and the second liquid is a monomer having an ethylenically unsaturated group. And at least one of the first and second liquids relates to an adhesive set containing a (meth) acrylic elastomer having a weight average molecular weight of 250,000 or more.

The adhesive set is an adhesive set that can be cured at room temperature and has excellent adhesiveness to adherends made of different materials. Therefore, by arranging the two liquids provided in the adhesive set between the adherends, it is possible to cure at room temperature, that is, to bond the adherends to each other at room temperature, and the adherends are made of different materials. Even when it is formed of, excellent adhesiveness is exhibited.

On one side, the glass transition temperature of the (meth) acrylic elastomer may be 80 ° C. or lower.

In one aspect, the weight average molecular weight of the (meth) acrylic elastomer may be 300,000 or more, and may be 400,000 or more.

Another aspect of the present invention includes a step of adhering adherends to each other using the adhesive set, and in the step, the first liquid and the second liquid are arranged between the adherends. Regarding the manufacturing method.

According to the above manufacturing method, a structure can be obtained in which the adherends can be adhered to each other at room temperature and the adherends made of different materials are suitably adhered to each other.

According to the present invention, there is an adhesive set capable of curing at room temperature, which has excellent adhesiveness to adherends made of different materials, and a method for producing a structure using the adhesive set. Provided.

Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to the following embodiments. In addition, in this specification, (meth) acrylic means acrylic and corresponding methacrylic.

(Adhesive set)
The adhesive set according to the present embodiment is an adhesive set (also referred to as a two-component adhesive) including a first liquid containing a polymerization initiator and a second liquid containing a reducing agent. At least one of the first liquid and the second liquid contains a monomer having an ethylenically unsaturated group (hereinafter, also referred to as "component (A)"), and at least one of the first liquid and the second liquid is a (meth) acrylic elastomer. (Hereinafter also referred to as "component (B)"). The adhesive set according to the present embodiment is an adhesive set that can be cured at room temperature and has excellent adhesiveness to adherends made of different materials. The reason for this effect is not always clear, but because the (meth) acrylic elastomer has excellent compatibility with monomers having ethylenically unsaturated groups, this adhesive cures quickly even at room temperature and is heterogeneous. It is considered that the adhesive is also excellent for an adherend formed of the above material (hereinafter, also referred to as “a different type of adherend”).

From the viewpoint of excellent affinity when mixing the first liquid and the second liquid, increasing the mixing degree, and suppressing variation in characteristics, in one embodiment, the first liquid is the component (A) and (B). It contains a component and a polymerization initiator, and the second liquid contains a component (A), a component (B) and a reducing agent.

In another embodiment, the first liquid contains the component (A), the component (B) and the polymerization initiator, and the second liquid contains the components (A) and (B) containing a reducing agent. Does not contain). In another embodiment, the first liquid contains a polymerization initiator (does not contain the component (A) and the component (B)), and the second liquid contains the component (A), the component (B) and the reducing agent. Contains. In another embodiment, the first liquid contains the component (A) and the polymerization initiator (does not contain the component (B)), and the second liquid contains the component (B) and the reducing agent (((). A) Contains no ingredients). In another embodiment, the first liquid contains the component (B) and the polymerization initiator (does not contain the component (A)), and the second liquid contains the component (A) and the reducing agent (((). B) Contains no ingredients).

In another embodiment, the first liquid contains the component (A), the component (B) and the polymerization initiator, and the second liquid contains the component (A) and the reducing agent (component (B)). Does not contain). In another embodiment, the first liquid contains the component (A), the component (B) and the polymerization initiator, and the second liquid contains the component (B) and the reducing agent (component (A)). Does not contain). In another embodiment, the first liquid contains the component (A) and the polymerization initiator (does not contain the component (B)), and the second liquid contains the component (A), the component (B) and the reducing agent. Contains. In another embodiment, the first liquid contains the component (B) and the polymerization initiator (does not contain the component (A)), and the second liquid contains the component (A), the component (B) and the reducing agent. Contains.

(Component (A): Monomer having an ethylenically unsaturated group)
The component (A) has an ethylenically unsaturated group (CH ₂ = CR-, R represents a hydrogen atom or a methyl group). The component (A) may contain a carboxyl group, an ester group, an amide group, a cyano group, a phosphoric acid group, a phosphonic acid group, a triazine ring, a thiol group and the like in addition to the ethylenically unsaturated group. The component (A) is a monofunctional monomer having one ethylenically unsaturated group, a bifunctional monomer having two ethylenically unsaturated groups, or a trifunctional or higher polyfunctional monomer having three or more ethylenically unsaturated groups. It may be any of.

The component (A) preferably contains a (meth) acrylic monomer having at least one (meth) acryloyl group from the viewpoint of excellent dispersibility in the (meth) acrylic elastomer. The component (A) may contain acrylonitrile and the like.

The (meth) acrylic monomer may be, for example, (meth) acrylic acid, alkyl (meth) acrylate or the like. The number of carbon atoms of the alkyl group in the alkyl (meth) acrylate may be, for example, 1 to 18, 1 to 12 or 1 to 8. The alkyl group may be linear, branched or cyclic. The alkyl (meth) acrylate may be, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, dicyclopentanyl (meth) acrylate, or the like, and (meth). From the viewpoint of further excellent dispersibility in acrylic elastomer, methyl methacrylate is preferable.

The (meth) acrylic monomer may contain a phosphoric acid group. Examples of such (meth) acrylic monomers include acid phosphooxyethyl (meth) acrylate, acid phosphooxypropyl (meth) acrylate, acid phosphooxypolyoxyethylene glycol mono (meth) acrylate, and acid phosphooxypolyoxypropylene. Examples thereof include glycol mono (meth) acrylate, 2,2'-di (meth) acryloyloxydiethyl phosphate, EO (ethylene oxide) -modified di (meth) acrylate, and phosphoric acid-modified epoxy (meth) acrylate. The (meth) acrylic monomer may be, for example, a (meth) acrylic monomer having a triazine ring such as isocyanuric acid-modified (meth) acrylate. The (meth) acrylic monomer may be, for example, a (meth) acrylic monomer having an amino group such as acrylamide.

The (meth) acrylic monomer may contain two or more (meth) acryloyl groups. Examples of such (meth) acrylic monomers include bifunctional monomers such as diethylene glycol di (meth) acrylate and 1,6-hexanediol di (meth) acrylate, trimethylolpropane triacrylate, and pentaerythritol tri (meth). ) It may be a trifunctional monomer such as acrylate or a tetrafunctional monomer such as ditrimethylolpropane tetra (meth) acrylate. Further, the (meth) acrylic monomer may be a (meth) acrylate containing 5 or more (meth) acryloyl groups.

One of these components (A) can be used alone or in combination of two or more. When the component (A) is contained in both the first solution and the second solution, the component (A) contained in the first solution and the component (A) contained in the second solution may be the same as each other. They may be different, preferably the same as each other.

The total content of the component (A) in the first solution and the second solution may be, for example, 5 parts by mass or more with respect to 100 parts by mass of the total amount of the components (A) and (B), and is curable. From the viewpoint, it is preferably 10 parts by mass or more, more preferably 20 parts by mass or more. The total amount of the content may be, for example, 99 parts by mass or less with respect to 100 parts by mass of the total amount of the component (A) and the component (B).

式中、Ｒ^１は、水素原子又はメチル基を表し、Ｒ^２は、水素原子又は１価の有機基を表す。((B) component: (meth) acrylic elastomer)
The (meth) acrylic elastomer is an elastomer containing a structural unit represented by the following formula (1).

In the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² represents a hydrogen atom or a monovalent organic group.

The ^{organic group represented by R 2} may be, for example, a hydrocarbon group. The hydrocarbon group may be chain or cyclic. The chain hydrocarbon group may be linear or branched. The number of carbon atoms of these hydrocarbon groups may be, for example, 1 to 20, 1 to 15 or 1 to 10. The hydrocarbon group may be an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a cycloalkyl group or the like.

Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group and the like. Examples of the alkenyl group include a vinyl group, a propenyl group, a butenyl group and the like. Examples of the alkynyl group include an ethynyl group, a propargyl group, a butynyl group, a pentynyl group, a hexynyl group and the like. Examples of the aryl group include a phenyl group, a toluic group, a naphthyl group and the like. Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclopentadienyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, a cyclodecyl group, a dicyclopentanyl group and the like. ..

The ^{organic group represented by R 2} may have a substituent other than the hydrocarbon group. As the substituent, the optimum substituent can be selected from the viewpoint of adhesiveness according to the type of material used for the adherend. The substituent may be, for example, a glycidyl group, a carboxyl group, a phosphoric acid group, a sulfo group, a phosphonic acid group, a hydroxyl group, a nitro group, a cyano group, an amino group, an alkoxy group, an acyloxy group or the like, and is formed of a metal. From the viewpoint of excellent adhesion to the adherend, a glycidyl group, a hydroxyl group, a phosphoric acid group, a phosphonic acid group, a nitro group, a cyano group, an amino group and the like are preferable.

The (meth) acrylic elastomer may further contain a structural unit represented by the following formula (2) (a structural unit derived from acrylonitrile) in addition to the structural unit represented by the formula (1).

The (meth) acrylic elastomer may further contain a structural unit represented by the following formula (3) (a structural unit derived from acrylamide) in addition to the structural unit represented by the formula (1).

The (meth) acrylic elastomer contains one or more of the above-mentioned structural units so as to have rubber elasticity, and preferably contains two or more of the above-mentioned structural units. The (meth) acrylic elastomer may contain only one or more of the above-mentioned structural units as the structural unit. In other words, the (meth) acrylic elastomer may be an elastomer that does not contain structural units other than the structural units described above (for example, structural units derived from olefins such as ethylene, propylene, and butadiene).

In one embodiment, the (meth) acrylic elastomer may consist of two or more types of structural units represented by the formula (1). In this case, the (meth) acrylic elastomer is represented by the formula (1), and is represented by the formula (1) with one or more structural units in which the organic group represented by ^{R 2 is a hydrocarbon group.} , The ^{organic group represented by R 2} may consist of one or more structural units having a glycidyl group or a hydroxyl group.

In another embodiment, the (meth) acrylic elastomer may consist of a structural unit represented by the formula (1) and a structural unit represented by the formula (2). In this case, (meth) acrylic elastomers, as a structural unit represented by the formula (1), may contain two or more structural units represented by the formula (1), the organic group represented by R ² There and one or more structural units is a hydrocarbon group, represented by the formula (1), one or two or more structural units which organic group represented by R ² is a glycidyl group or a hydroxyl group And may be included.

The content of the structural unit represented by the formula (1) may be 1% by mass or more, 20% by mass or more, or 50% by mass or more based on the total amount of the structural units of the (meth) acrylic elastomer.

Is represented by the formula (1), the content of the structural unit organic group represented by R ² is a hydrocarbon group, (meth) based on the structural unit the total amount of acrylic elastomer, 1 wt% or more, 20 wt% It may be more than or equal to 30% by mass, and may be 99% by mass or less or 95% by mass or less.

Is represented by the formula (1), the content of the structural unit organic group represented by R ² has a substituent other than a hydrocarbon group, (meth) based on the structural unit the total amount of acrylic elastomer, or 1 wt% Alternatively, it may be 2% by mass or more, and may be 60% by mass or less, 50% by mass or less, or 40% by mass or less.

The content of the structural unit represented by the formula (2) may be 60% by mass or less, 50% by mass or less, or 40% by mass or less based on the total amount of the structural units of the (meth) acrylic elastomer.

The elastic modulus of the (meth) acrylic elastomer is preferably 3000 MPa or less, 2000 MPa or less, or 1500 MPa or less from the viewpoint of excellent suppression of warpage when joining different types of adherends. The elastic modulus of the (meth) acrylic elastomer is calculated from the initial slope of the stress-strain curve by performing a tensile test. The tensile test is performed by cutting a test piece cut into 5 mm × 0.5 mm using an autograph (“AGS-X” manufactured by Shimadzu Corporation) (distance between chucks: 20 mm, tensile speed: 5 mm / min).

The glass transition temperature (Tg) of the (meth) acrylic elastomer is preferably 130 ° C. or lower, 100 ° C. or lower, 80 ° C. or lower, 70 ° C. or lower, 60 ° C. or lower from the viewpoint of further excellent adhesiveness to different types of adherends. , 50 ° C or lower, 40 ° C or lower, 30 ° C or lower, 20 ° C or lower, 0 ° C or lower, or -10 ° C or lower. The glass transition temperature (Tg) of the (meth) acrylic elastomer may be, for example, −50 ° C. or higher. The (meth) acrylic elastomer may have two or more glass transition temperatures (Tg). In this case, it is preferable that at least one of the two or more glass transition temperatures (Tg) is within the above range, and more preferably all of the two or more glass transition temperatures (Tg) are within the above range. ..

The glass transition temperature (Tg) of the (meth) acrylic elastomer means the intermediate point glass transition temperature value measured by differential scanning calorimetry using a differential scanning calorimeter (for example, "Thermo Plus 2" manufactured by Rigaku Co., Ltd.). Specifically, the glass transition temperature (Tg) of the (meth) acrylic elastomer measures the change in calorific value of the (meth) acrylic elastomer under the conditions of a measurement temperature range of -50 to 300 ° C. and a heating rate of 10 ° C./min. It means the midpoint glass transition temperature calculated by a method based on JIS K7121: 1987.

The weight average molecular weight (Mw) of the (meth) acrylic elastomer is 250,000 or more, preferably 300,000 or more, more preferably 400,000 or more, 500,000 or more, 600,000 or more, or 700,000 or more. May be good. The weight average molecular weight (Mw) of the (meth) acrylic elastomer may be, for example, 1 million or less. The larger the weight average molecular weight (Mw) of the (meth) acrylic elastomer, the better the elongation, strength and breaking energy of the cured product of the mixture of the first liquid and the second liquid, and the adhesiveness (stress) between different adherends. It tends to be excellent in relaxation).

The weight average molecular weight (Mw) of the (meth) acrylic elastomer is measured by the gel permeation chromatography (GPC) method under the following conditions, and means a value determined using polystyrene as a standard substance.
-Measuring equipment: HLC-8320GPC (product name, manufactured by Tosoh Corporation)
-Analytical column: TSKgel SuperMultipore HZ-H (3 connected) (Product name, manufactured by Tosoh Corporation)
-Guard column: TSKguardvolume SuperMP (HZ) -H (product name, manufactured by Tosoh Corporation)
-Eluent: THF
・ Measurement temperature: 25 ° C

The (meth) acrylic elastomer may be used alone or in combination of two or more. When the (meth) acrylic elastomer is contained in both the first liquid and the second liquid, the (meth) acrylic elastomer contained in the first liquid and the (meth) acrylic elastomer contained in the second liquid are the same as each other. They may be present or different, and are preferably the same as each other.

The total content of the component (B) in the first liquid and the second liquid may be, for example, 5 parts by mass or more with respect to 100 parts by mass of the total amount of the components (A) and (B), and is curable. From the viewpoint, it is preferably 10 parts by mass or more, more preferably 20 parts by mass or more. The total amount of the content is, for example, 99 parts by mass or less with respect to 100 parts by mass of the total amount of the component (A) and the component (B).

(Polymerization initiator)
The polymerization initiator may be, for example, a radical polymerization initiator. The radical polymerization initiator may be, for example, an organic peroxide or an azo compound. The organic peroxide may be, for example, hydroperoxide, peroxydicarbonate, peroxyester, peroxyketal, dialkyl peroxide, diacyl peroxide or the like. The azo compound may be AIBN (2,2'-azobisisobutyronitrile), V-65 (azobisdimethylvaleronitrile) or the like. The polymerization initiator may be used alone or in combination of two or more.

Examples of the hydroperoxide include diisopropylbenzene hydroperoxide and cumene hydroperoxide.

Examples of peroxydicarbonate include di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, di-2-ethoxymethoxyperoxydicarbonate, and di-2-ethoxymethoxyperoxydicarbonate. Examples thereof include (2-ethylhexylperoxy) dicarbonate, dimethoxybutylperoxydicarbonate, and di (3-methyl-3methoxybutylperoxy) dicarbonate.

Examples of the peroxyester include cumyl peroxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethylperoxyneodecanoate, and t. -Hexylperoxyneodecanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di ( 2-Ethylhexanoylperoxy) hexane, 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanonate, t-hexylperoxy-2-ethylhexanonate, t-butylperoxy-2 -Ethylhexanonate, t-butylperoxyisobutyrate, 1,1-bis (t-butylperoxy) cyclohexane, t-butylperoxy-3,5,5-trimethylhexanone, t-butylper Oxylaurate, 2,5-dimethyl-2,5-di (m-toluyl peroxy) hexane, t-hexyl peroxybenzoate, t-butyl peroxyacetate and the like can be mentioned.

Examples of the peroxyketal include 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, and 1,1-. Bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclododecane, 2,2-bis (t-butylperoxy) decane, etc. Can be mentioned.

Examples of dialkyl peroxides include α, α'-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, and t-. Butylcumyl peroxide and the like can be mentioned.

Diacyl peroxides include isobutyl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearoyl peroxide, and succinic peroxide. , Benzoyl peroxytoluene, benzoyl peroxide and the like.

From the viewpoint of storage stability, the radical polymerization initiator is preferably a peroxide, more preferably a hydroperoxide, and even more preferably a cumene hydroperoxide.

The content of the polymerization initiator in the first liquid is, for example, 0.1 part by mass or more with respect to 100 parts by mass of the total amount of the components (A) and (B) contained in the first liquid and the second liquid. It may be 20 parts by mass or less.

(Reducing agent)
The reducing agent may be, for example, a tertiary amine, a thiourea derivative, a transition metal salt or the like. Examples of the tertiary amine include triethylamine, tripropylamine, tributylamine, N, N-dimethylparatoluidine and the like. Examples of the thiourea derivative include 2-mercaptobenzimidazole, methylthiourea, dibutylthiourea, tetramethylthiourea, ethylenethiourea and the like. Examples of the transition metal salt include cobalt naphthenate, copper naphthenate, vanadyl acetylacetonate and the like. The reducing agent may be used alone or in combination of two or more.

The reducing agent is preferably a thiourea derivative or a transition metal salt from the viewpoint of curing rate. The thiourea derivative may be, for example, ethylene thiourea. From a similar point of view, the transition metal salt is preferably vanadyl acetylacetonate.

The content of the reducing agent in the second liquid is, for example, 0.01 part by mass or more with respect to 100 parts by mass of the total amount of the components (A) and (B) contained in the first liquid and the second liquid. The content is, for example, 10 parts by mass or less with respect to 100 parts by mass of the total amount of the components (A) and (B) contained in the first liquid and the second liquid.

The adhesive set may contain other components other than the component (A), the component (B), the polymerization initiator and the reducing agent. Other components may be contained in one or both of the first liquid and the second liquid, and may be contained in a third liquid different from the first liquid and the second liquid.

The other components may be polymerization inhibitors for the purpose of improving storage stability. Examples of the polymerization inhibitor include hydroquinone, methylhydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol, phenothiazine and the like.

The other components may be paraffins for the purpose of preventing polymerization inhibition by oxygen. Examples of paraffins include paraffin wax, microcrystalline wax, carnauba wax, beeswax, lanolin, whale wax, ceresin, candelilla wax and the like.

The other component may be a filler for the purpose of preventing dripping, imparting tincture property, improving adhesive strength, and the like. Examples of the shape of the filler include a fibrous filler and a spherical filler.

Examples of the filler components include metal fillers such as silver powder, gold powder, copper powder, and nickel powder, alumina, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, and oxidation. Examples thereof include inorganic fillers such as magnesium, aluminum oxide, aluminum nitride, crystalline silica, amorphous silica, boron nitride, titania, glass, iron oxide and ceramics, and organic fillers such as carbon and rubber fillers.

(Manufacturing method of structure using adhesive set)
The method for manufacturing a structure using the adhesive set according to the present embodiment includes a step (adhesion step) of adhering adherends to each other using the above-mentioned adhesive set.

In the bonding step, the first liquid and the second liquid are arranged between the adherends. The adherend is made of, for example, a metal such as steel, iron, copper, tinplate, aluminum, or stainless steel, a resin, carbon fiber reinforced plastic (CFRP), or the like. The two adherends to be bonded may be made of the same kind of material as each other, or may be made of different materials from each other. Since the adhesive set used in this manufacturing method has excellent adhesiveness to different kinds of adherends, even when one adherend and another adherend are made of different materials from each other. , A structure in which the adherends are suitably adhered to each other can be obtained.

In the bonding step, specifically, for example, one adherend and another adherend are arranged with a predetermined gap, and a device such as a mixing nozzle is used to fill the gap with the first liquid and the first liquid. Inject the two liquids. In the bonding step, the first liquid and the second liquid may be mixed substantially at the same time as the injection between the adherends, or the first liquid and the second liquid may be mixed immediately before the injection between the adherends. Good. When the first liquid and the second liquid are mixed with each other, the mixture is cured and the adherends are adhered to each other.

Since the adhesive set used in this production method can be cured at room temperature, the temperature at which the bonding step is carried out may be, for example, 100 ° C. or lower, 80 ° C. or lower, or 50 ° C. or lower, and 5 ° C. or higher and 10 ° C. or higher. It may be ℃ or more, or 20 ℃ or more. The bonding step may be carried out while changing the temperature stepwise. For example, after bonding at a temperature of 50 ° C. or lower, aftercure may be performed at a temperature of 100 ° C. or lower.

The structure obtained by the above manufacturing method includes one adherend, another adherend, and an adhesive portion for adhering one adherend and another adherend. The adhesive portion is a cured product of a mixture of liquids (for example, a mixture of the first liquid and the second liquid) constituting the above-mentioned adhesive set.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the Examples.

(Synthesis Example 1A)
A 0.5 L flask equipped with a stirrer, a thermometer, a nitrogen gas introduction tube, a discharge tube, and a heating jacket was used as a reactor, and nitrogen was flowed into the flask at 150 mL / min. As monomers, butyl acrylate (BA) 20 g, dicyclopentanyl acrylate (manufactured by Hitachi Kasei Co., Ltd., FA-513AS) 25.8 g, butyl methacrylate (BMA) 31.1 g, glycidyl methacrylate (GMA) 4.5 g, and 2 -Ethylhexyl methacrylate (2EHMA) 18.6 g was mixed. A monomer mixture was prepared by dissolving 0.4 g of lauroyl peroxide as an initiator, 0.004 g of n-octyl mercaptan as a chain transfer agent, and 0.1 g of L-ascorbic acid as an antioxidant in these monomers. To the monomer mixture, 200 g of water and 1.7 g of polyvinyl alcohol (PVA) as a dispersion aid were added to obtain a dispersion liquid. After supplying a dispersion liquid in which nitrogen was bubbled to reduce the dissolved oxygen to 1 ppm or less into the flask, the flask was stirred and heated at a temperature inside the flask of 60 ° C. and a stirring rotation speed of 22 times / min, and polymerized for 6 hours. Then, the temperature was raised to 90 ° C., the reaction was further carried out for 2 hours, and after cooling, washing with water, dehydration and drying were carried out to obtain a (meth) acrylic elastomer (hereinafter referred to as (meth) acrylic elastomer 1A).

<Measurement of weight average molecular weight>
The weight average molecular weight (Mw) of the obtained (meth) acrylic elastomer was measured using a gel permeation chromatography (GPC) method under the following conditions, using polystyrene as a standard substance. The results obtained are shown in Table 1.
-Measuring equipment: HLC-8320GPC (product name, manufactured by Tosoh Corporation)
-Analytical column: TSKgel SuperMultipore HZ-H (3 connected) (Product name, manufactured by Tosoh Corporation)
-Guard column: TSKguardvolume SuperMP (HZ) -H (product name, manufactured by Tosoh Corporation)
-Eluent: THF
・ Measurement temperature: 25 ° C

<Measurement of glass transition temperature (Tg)>
The glass transition temperature (Tg) of the obtained (meth) acrylic elastomer was measured using a differential scanning calorimeter (“Thermo Plus 2” manufactured by Rigaku Co., Ltd.). The measurement was performed in a nitrogen atmosphere under the conditions of a temperature range of −50 to 300 ° C. and a heating rate of 10 ° C./min. The midpoint glass transition temperature was calculated by a method according to JIS K7121: 1987. The results obtained are shown in Table 1.

(Synthesis Example 1B)
It was synthesized under the same conditions as in Synthesis Example 1A except that it was changed to 0.6 g of lauroyl peroxide as an initiator, contained the same structural units as the (meth) acrylic elastomer 1A, and had Mw and Tg shown in Table 1 (. A (meth) acrylic elastomer (hereinafter referred to as (meth) acrylic elastomer 1B) was obtained.

(Synthesis Example 1C)
It was synthesized under the same conditions as in Synthesis Example 1A except that it was changed to 0.75 g of lauroyl peroxide as an initiator, contained the same structural units as the (meth) acrylic elastomer 1A, and had Mw and Tg shown in Table 1 ( A (meth) acrylic elastomer (hereinafter referred to as (meth) acrylic elastomer 1C) was obtained.

(Synthesis Example 2A)
Synthesis was performed under the same conditions as in Synthesis Example 1A except that BA69.5 g, 28 g of acrylonitrile (AN), and 2.5 g of GMA were used instead of the monomers used in Synthesis Example 1A, and Mw and Tg shown in Table 1 were obtained. A (meth) acrylic elastomer having (hereinafter referred to as (meth) acrylic elastomer 2A) was obtained.

(Synthesis Example 2B)
It was synthesized under the same conditions as in Synthesis Example 2A except that it was changed to 0.6 g of lauroyl peroxide as an initiator, contained the same structural units as the (meth) acrylic elastomer 2A, and had Mw and Tg shown in Table 1 ( A (meth) acrylic elastomer (hereinafter referred to as (meth) acrylic elastomer 2B) was obtained.

(Synthesis Example 2C)
It was synthesized under the same conditions as in Synthesis Example 2A except that it was changed to 0.75 g of lauroyl peroxide as an initiator, contained the same structural units as the (meth) acrylic elastomer 2A, and had Mw and Tg shown in Table 1 ( A (meth) acrylic elastomer (hereinafter referred to as (meth) acrylic elastomer 2C) was obtained.

(Synthesis Example 3)
Instead of the monomer used in Synthesis Example 1, BA10 g, dicyclopentanyl acrylate (manufactured by Hitachi Kasei Co., Ltd., FA-513AS) 25.8 g, MMA 21.1 g, BMA 20 g, GMA 4.5 g, and 2EHMA 18.6 g were used. A (meth) acrylic elastomer (hereinafter referred to as (meth) acrylic elastomer 3) was obtained by synthesizing under the same conditions as in Synthesis Example 1A except for the above.

(Synthesis Example 4)
Synthesized under the same conditions as in Synthesis Example 1A, except that the initiator was changed to 0.75 g of lauroyl peroxide and the temperature inside the flask was changed to 65 ° C., and the same structural unit as the (meth) acrylic elastomer 1A was used. A (meth) acrylic elastomer (hereinafter referred to as (meth) acrylic elastomer 4) containing Mw and Tg shown in Table 1 was obtained.

(Examples 1 to 9)
The (meth) acrylic monomer, the (meth) acrylic elastomer 1A to 1C, 2A to 2C or 3, and the polymerization initiator were mixed in the blending amounts shown in Table 1 to obtain a first liquid. Further, the (meth) acrylic monomer, the (meth) acrylic elastomer 1A to 1C, 2A to 2C or 3, and the reducing agent were mixed in the blending amounts shown in Table 1 to obtain a second liquid. Details of each component used are shown below.
(Meta) Acrylic Monomer: Methyl Methacrylate Polymerization Initiator: Cumene Hydroperoxide Reducing Agent 1: Ethethylenethiourea Reducing Agent 2: Vanadyl acetylacetonate

(Comparative Examples 1 to 4)
Instead of each (meth) acrylic elastomer used in the examples, polymethylmethacrylate (PMMA1, Tg: 105 ° C., Mw: 350,000), polymethylmethacrylate (PMMA2, Tg: 105 ° C., Mw: 500,000), butadiene. Same as in Example 1 except that the compounding amount shown in Table 1 was changed by using a based polymer (TH-21 (manufactured by Denka Co., Ltd., trade name), Tg: 83 ° C.) or (meth) acrylic elastomer 4. The first liquid and the second liquid were obtained.

<Evaluation of adhesive>
The adhesives obtained in Examples and Comparative Examples were evaluated for room temperature curability and adhesiveness between different types of adherends according to the following methods. The results obtained are shown in Table 1.

<Preparation of evaluation sample>
A 0.2 mm spacer was placed between an aluminum plate having a size of 5 mm × 100 mm and a thickness of 0.5 mm and a cold-rolled steel plate so that the thickness of the adhesive was 0.2 mm. In this state, the first liquid and the second liquid were mixed between the aluminum plate and the cold-rolled steel plate while mixing using a mixing nozzle (manufactured by Tomita Engineering Co., Ltd.) to prepare an evaluation sample 1.

Evaluation sample 2 is the same as evaluation sample 1 except that a CFRP plate having a size of 5 mm × 100 mm and a thickness of 2 mm is used instead of an aluminum plate having a size of 5 mm × 100 mm and a thickness of 0.5 mm. Was produced.

(Room temperature curability)
After curing the evaluation samples 1 and 2 at room temperature (25 ° C.) for 1 day, the plate was peeled off and it was visually confirmed whether or not the adhesive was cured. The one in which the adhesive was cured in both the evaluation samples 1 and 2 was evaluated as A, and the one in which the adhesive was not cured in at least one of the evaluation samples 1 and 2 was evaluated as B.

(Adhesion between different adherends)
Evaluation samples 1 and 2 were heated at 170 ° C. for 20 minutes and then allowed to cool at room temperature (30 ° C.), and the presence or absence of warpage or peeling was visually confirmed. Among those having no warp or peeling of 5 mm or more, those having a warp of 1 mm or less were evaluated as A +, those having a warp of more than 1 mm and smaller than 3 mm were evaluated as A, and those having a warp of 3 mm or more were evaluated as A-. .. In addition, those having a warp or peeling of 5 mm or more were evaluated as B. For the warp, the distance between the other end and the table was measured while one of the ends of the evaluation sample was fixed on a table parallel to the ground.

Claims (6)

A first liquid containing a polymerization initiator and a second liquid containing a reducing agent are provided.
At least one of the first liquid and the second liquid further contains a monomer having an ethylenically unsaturated group.
An adhesive set in which at least one of the first liquid and the second liquid further contains a (meth) acrylic elastomer having a weight average molecular weight of 250,000 or more. The adhesive set according to claim 1, wherein the glass transition temperature of the (meth) acrylic elastomer is 80 ° C. or lower. The adhesive set according to claim 1 or 2, wherein the (meth) acrylic elastomer has a weight average molecular weight of 300,000 or more. The adhesive set according to any one of claims 1 to 3, wherein the (meth) acrylic elastomer has a weight average molecular weight of 400,000 or more. A step of adhering adherends to each other using the adhesive set according to any one of claims 1 to 4 is provided.
A method for producing a structure, in which the first liquid and the second liquid are arranged between the adherends in the step. The method for producing a structure according to claim 5, wherein the adherends are made of materials different from each other.