JP2024118953A - Composite and manufacturing method thereof - Google Patents

Abstract

To provide a composite that has increased peel strength and in which bonding between members is facilitated, and a method for manufacturing the composite.SOLUTION: The present invention provides: a composite comprising at least two members, wherein the at least two members are bonded together, the bonded members are made of different materials, and each of the at least two members contains a copolymer having conjugated diene units and non-conjugated olefin units; and a method for manufacturing the composite, the method comprising bringing the at least two members into contact with each other, and heating, bonding, and solidifying the at least two contacting members.SELECTED DRAWING: None

Description

The present invention relates to a composite and a method for producing the same.

Conventionally, in the adhesion between dissimilar materials, for example rubber and resin, research into adhesion has been progressing.
For example, Patent Document 1 listed below discloses a laminate formed by bonding vulcanized rubber and resin together, which is formed by pretreating at least one of the adhesive surfaces of the vulcanized rubber and the resin, laminating the vulcanized rubber and the resin, and then thermally compressing the laminate.

JP 2013-144388 A

However, it was found that the laminate formed by bonding vulcanized rubber and resin described in Patent Document 1 above does not have sufficient adhesive strength, and there is still room for improvement in adhesive strength.

Therefore, an object of the present invention is to provide a composite body having improved peel strength and in which members can be easily bonded to each other.
Another object of the present invention is to provide a method for producing such a composite.

The essential features of the composite and the method for producing the composite of the present invention that solve the above problems are as follows:

[1] A composite body consisting of at least two members,
The at least two members are joined together,
The joined parts are made of different materials,
The composite, wherein the at least two components both contain a copolymer having conjugated diene units and non-conjugated olefin units.
In this case, by including a copolymer having a conjugated diene unit and a non-conjugated olefin unit in both components, the peel strength is improved and further, components made of different materials can be easily bonded to each other.

[2] The composite according to [1], wherein the melting point of the copolymer is 50 to 120°C.
In this case, the crystallinity of the copolymer increases, and the peel strength of the composite increases.

[3] The copolymer has a content of the conjugated diene unit of more than 0 mol% and not more than 50 mol%, and a content of the non-conjugated olefin unit of 50 mol% or more and less than 100 mol%. The composite according to [1] or [2].
In this case, the peel strength of the composite is improved.

[4] The composite according to any one of [1] to [3], wherein the copolymer further contains an aromatic vinyl unit.
In this case, while improving the rigidity of the copolymer, the elasticity is not easily impaired and high peel strength can be obtained.

[5] The copolymer has a conjugated diene unit content of 1 to 50 mol%, a non-conjugated olefin unit content of 40 to 97 mol%, and an aromatic vinyl unit content of 2 to 35 mol%. The composite according to [4].
In this case, the peel strength of the composite can be improved.

[6] The composite according to any one of [1] to [5], wherein the content of the copolymer in each of the members is 0.1 to 25 mass%.
In this case, the peel strength is improved and further, the members can be easily bonded to each other.

[7] The composite according to any one of [1] to [6], wherein the difference in melting point of the copolymer between the members is 30° C. or less.
In this case, the members can be bonded to each other more easily.

[8] The composite according to any one of [1] to [7], wherein at least one of the at least two members contains 3 to 20% by mass of the copolymer and 50% by mass or more of a diene rubber.
In this case, the peel strength between the diene rubber-containing member and other members is improved, and further, adhesion between the members is facilitated.

[9] The composite according to any one of [1] to [8], wherein at least one of the members contains 0.1 to 10% by mass of the copolymer and contains an asphalt component.
In this case, the peel strength between the member containing the asphalt component and other members is improved, and further, adhesion between the members becomes easier.

[10] The composite according to any one of [1] to [9], wherein at least one of the members contains 50% by mass or more of a resin component.
In this case, the peel strength between the member containing the resin component and the other member is improved, and further, the members are easily bonded to each other.

[11] A method for producing the composite according to any one of [1] to [10],
contacting the at least two members;
and heating the at least two members in contact to bond and fix them together.
In this case, a composite can be produced in which the peel strength is improved and further in which members made of different materials can be easily bonded to each other.

The present invention provides a composite that has improved peel strength and allows easy bonding of components.

The present invention is described in detail below.

<Definition>
The compounds described herein may be derived in whole or in part from fossil sources, from biological sources such as plant sources, from recycled sources such as used tires, or from a mixture of two or more of fossil sources, biological sources, and/or renewable sources.

In this specification, the terms "rubber component" and "diene rubber" do not include "copolymers having conjugated diene units and non-conjugated olefin units."

<Complex>
A composite according to one embodiment of the present invention is a composite comprising at least two members, the at least two members being bonded to each other, the bonded members being made of different materials, and the at least two members each containing a copolymer having conjugated diene units and non-conjugated olefin units (hereinafter sometimes simply referred to as a "copolymer").

The composite of this embodiment is made up of at least two members, and the at least two members are joined together.

The at least two members are made of different materials. The materials constituting the members are not particularly limited and can be selected appropriately depending on the purpose. For example, the members may contain a rubber component, an asphalt component, a resin component, etc. Although not particularly limited, one of the at least two members may contain a rubber component and the other member may contain an asphalt component, one of the at least two members may contain a rubber component and the other member may contain a resin component, or one of the at least two members may contain an asphalt component and the other member may contain a resin component.

The at least two components used in the composite of this embodiment each contain a copolymer having conjugated diene units and non-conjugated olefin units. By including the copolymer in at least two components, the peel strength is improved and adhesion between the components is facilitated, even in a composite made of different materials.

<Materials>
The material constituting the member of the present embodiment is not particularly limited and can be appropriately selected depending on the purpose. The member may contain, for example, a rubber component, an asphalt component, a resin component, etc.

The at least two components each contain a copolymer having conjugated diene units and non-conjugated olefin units. By including the copolymer in each of the components constituting the composite, the peel strength is improved and the components can be easily bonded together even if they are made of different materials.

The content of the copolymer in each of the members is preferably 0.1 to 25% by mass from the viewpoint of improving the peel strength and facilitating adhesion between the members. From the same viewpoint, the content of the copolymer in each of the members is more preferably 0.2% by mass or more. Moreover, the content of the copolymer in each of the members is more preferably 23% by mass or less, even more preferably 20% by mass or less, and particularly preferably 15% by mass or less.
From the viewpoints of improving the peel strength and facilitating adhesion between the members, the content of the copolymer in each of the members is preferably 3 to 40 parts by mass per 100 parts by mass of the rubber component. From the same viewpoint, the content of the copolymer is preferably 10 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the rubber component.

At least one of the at least two members may contain 3 to 20% by mass of the copolymer and 50% by mass or more of the diene rubber. In this case, the peel strength between the member containing the diene rubber and the other member is improved, and further, the members are easily bonded to each other. From the same viewpoint, the content of the copolymer is preferably 3% by mass or more, more preferably 4% by mass or more, and even more preferably 5% by mass or more. In addition, the content of the copolymer is preferably 20% by mass or less, more preferably 18% by mass or less, and even more preferably 15% by mass or less.
From the viewpoints of improving the peel strength between a diene rubber-containing member and another member and facilitating adhesion between the members, the content of the copolymer is preferably 3 to 40 parts by mass per 100 parts by mass of the rubber component. From the same viewpoint, the content of the copolymer is preferably 10 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the rubber component.
Here, the diene rubber does not include copolymers having conjugated diene units and non-conjugated olefin units.

At least one of the members may contain 0.1 to 10% by mass of the copolymer and may also contain an asphalt component. In this case, the peel strength between the member containing the asphalt component and the other member is improved, and further, the members are easily bonded to each other. From the same viewpoint, the content of the copolymer is preferably 0.1% by mass or more, and more preferably 0.2% by mass or more.
At least one of the members may contain 3 to 40 parts by mass of the copolymer relative to 100 parts by mass of the rubber component, and may also contain an asphalt component. In this case, the peel strength between the member containing the asphalt component and the other member is improved, and further, the members are easily bonded to each other. From the same viewpoint, the content of the copolymer is preferably 10 parts by mass or more and 20 parts by mass or less relative to 100 parts by mass of the rubber component.

Furthermore, at least one of the members may contain 50% by mass or more of a resin component. In this case, the peel strength between the member containing the resin component and other members is improved, making it easier to bond the members together.

The shape of the members used in the composite of this embodiment is not particularly limited and can be appropriately selected depending on the purpose. Specific examples include cords, sheets, blocks, etc.

The member of this embodiment can also be used as a component for various products. For example, it can be used as rubber, resin, asphalt, glass, metal, inorganic material, carbon fiber, etc.

<Copolymer>
The copolymer contained in the member used in the composite of this embodiment (hereinafter, sometimes simply referred to as "copolymer") has conjugated diene units and non-conjugated olefin units.
The copolymer of the present embodiment may be a binary copolymer consisting of two units, a conjugated diene unit and a non-conjugated olefin unit, or may be a ternary copolymer consisting of three units including an aromatic vinyl unit, or may be a multi-component copolymer containing other monomer units.

(Conjugated Diene Units)
The conjugated diene unit is a structural unit derived from a conjugated diene compound as a monomer.
Here, the conjugated diene compound refers to a conjugated diene compound. The conjugated diene compound preferably has 4 to 8 carbon atoms. Specific examples of such conjugated diene compounds include 1,3-butadiene, isoprene, 1,3-pentadiene, and 2,3-dimethyl-1,3-butadiene. The conjugated diene compound may be used alone or in combination of two or more kinds.

From the viewpoint of improving the peel strength of the composite, the conjugated diene compound as a monomer of the copolymer preferably contains at least one selected from the group consisting of 1,3-butadiene and isoprene, more preferably consists of only at least one selected from the group consisting of 1,3-butadiene and isoprene, and further preferably consists of only 1,3-butadiene.
In other words, the conjugated diene unit in the copolymer preferably contains at least one selected from the group consisting of 1,3-butadiene units and isoprene units, more preferably consists of at least one selected from the group consisting of 1,3-butadiene units and isoprene units, and further preferably consists of only 1,3-butadiene units.

When the copolymer is a binary copolymer, the content of the conjugated diene units is preferably more than 0 mol% and not more than 50 mol%. In this case, a copolymer having excellent elongation and weather resistance can be obtained. From the same viewpoint, it is more preferable that the proportion of the conjugated diene units in the binary copolymer is not more than 40 mol%.

In the binary copolymer, the ratio of 1,2 adducts (including 3,4 adducts) of the conjugated diene units is preferably 10 mol% or less. When the ratio is 10 mol% or less, the heat resistance and flex fatigue resistance of the copolymer can be improved. From the same viewpoint, the ratio of 1,2 adducts (including 3,4 adducts) of the conjugated diene units in the binary copolymer is more preferably 8 mol% or less, and even more preferably 6 mol% or less. Note that the ratio of 1,2 adducts (including 3,4 adducts) of the conjugated diene units is the ratio in the entire conjugated diene units, not the ratio in the entire copolymer. In addition, when the conjugated diene units are butadiene units, the ratio has the same meaning as the 1,2-vinyl bond amount.

When the copolymer is a terpolymer or a multicomponent copolymer, the content of conjugated diene units is preferably 1 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, and is preferably 50 mol% or less, more preferably 40 mol% or less, and even more preferably 30 mol% or less.

When the content of the conjugated diene unit is 1 to 50 mol % of the entire copolymer, the peel strength of the composite can be improved.
From the viewpoint of further improving the peel strength of the composite, the content of the conjugated diene unit is preferably in the range of 1 to 50 mol %, more preferably in the range of 5 to 40 mol %, and even more preferably in the range of 10 to 30 mol %, of the entire copolymer.

(Non-conjugated olefin units)
The non-conjugated olefin unit is a structural unit derived from a non-conjugated olefin compound as a monomer.
Here, the non-conjugated olefin compound refers to an aliphatic unsaturated hydrocarbon compound having one or more carbon-carbon double bonds. The non-conjugated olefin compound preferably has 2 to 10 carbon atoms. Specific examples of such non-conjugated olefin compounds include α-olefins such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene, and heteroatom-substituted alkene compounds such as vinyl pivalate, 1-phenylthioethene, and N-vinylpyrrolidone. The non-conjugated olefin compounds may be used alone or in combination of two or more kinds.

From the viewpoint of improving the peel strength of the composite, the non-conjugated olefin compound as a monomer of the copolymer is preferably an acyclic non-conjugated olefin compound, and the acyclic non-conjugated olefin compound is more preferably an α-olefin, further preferably an α-olefin containing ethylene, and particularly preferably composed of only ethylene.
In other words, the non-conjugated olefin units in the copolymer are preferably non-cyclic non-conjugated olefin units, and the non-cyclic non-conjugated olefin units are more preferably α-olefin units, further preferably α-olefin units containing ethylene units, and particularly preferably consisting of only ethylene units.

When the copolymer is a binary copolymer, the content of non-conjugated olefin units is preferably 50 mol% or more and less than 100 mol%. In this case, the peel strength of the composite can be effectively improved. From the same viewpoint, it is more preferable that the proportion of non-conjugated olefin units in the binary copolymer is 60 mol% or more.

When the copolymer is a terpolymer or a multicomponent copolymer, the content of the non-conjugated olefin unit is preferably 40 mol% or more, more preferably 45 mol% or more, even more preferably 55 mol% or more, particularly preferably 60 mol% or more, and is preferably 97 mol% or less, more preferably 95 mol% or less, and even more preferably 90 mol% or less. When the content of the non-conjugated olefin unit is 40 to 97 mol% of the entire copolymer, the peel strength can be improved.
From the viewpoint of further improving the peel strength of the composite, the content of the non-conjugated olefin unit is preferably in the range of 40 to 97 mol % of the entire copolymer, more preferably in the range of 45 to 95 mol %, even more preferably in the range of 55 to 90 mol %, and even more preferably in the range of 60 to 90 mol %.

(aromatic vinyl unit)
The copolymer preferably further contains an aromatic vinyl unit.
By containing an aromatic vinyl unit as a monomer, crystalline components such as ethylene crystalline components are cut, and excessive crystallization derived from non-conjugated olefin units is suppressed, and while improving the rigidity of the copolymer, elasticity is unlikely to be impaired, and the peel strength can be improved.
Here, the aromatic vinyl compound refers to an aromatic compound substituted with at least a vinyl group, and is not included in the conjugated diene compound. The aromatic vinyl compound preferably has 8 to 10 carbon atoms. Examples of such aromatic vinyl compounds include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, o,p-dimethylstyrene, o-ethylstyrene, m-ethylstyrene, and p-ethylstyrene. The aromatic vinyl compound may be a single type or a combination of two or more types.

From the viewpoint of improving the peel strength of the composite, the aromatic vinyl compound as a monomer of the copolymer preferably contains styrene, and more preferably consists of styrene alone. In other words, the aromatic vinyl unit in the copolymer preferably contains styrene units, and more preferably consists of styrene units alone.
Incidentally, the aromatic ring in the aromatic vinyl unit is not included in the main chain of the copolymer unless it is bonded to an adjacent unit.

When the copolymer is a terpolymer or a multicomponent copolymer, the content of the aromatic vinyl unit is preferably 2 mol% or more, more preferably 3 mol% or more, and preferably 35 mol% or less, more preferably 30 mol% or less, and even more preferably 25 mol% or less. When the content of the aromatic vinyl unit is 2 to 35 mol% of the entire copolymer, the peel strength of the composite can be improved.
From the viewpoint of further improving the peel strength of the composite, the content of the aromatic vinyl unit is preferably in the range of 2 to 35 mol %, more preferably in the range of 3 to 30 mol %, and even more preferably in the range of 3 to 25 mol %, of the entire copolymer.

From the viewpoint of obtaining the desired effect of the present invention, the content of other structural units than the conjugated diene unit, the non-conjugated olefin unit, and the aromatic vinyl unit is preferably 30 mol% or less of the entire copolymer, more preferably 20 mol% or less, and even more preferably 10 mol% or less, and it is particularly preferable that no other structural units are contained, that is, the content is 0 mol%. In other words, it is preferable that the copolymer is a binary copolymer consisting of two units, a conjugated diene unit and a non-conjugated olefin unit, or a ternary copolymer consisting of three units, a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit.

From the viewpoint of improving the peel strength of the composite, the copolymer is preferably a polymer obtained by polymerizing at least one kind of conjugated diene compound, one kind of non-conjugated olefin compound, and one kind of aromatic vinyl compound as monomers.
In other words, the copolymer is preferably a copolymer having only one type of conjugated diene unit, only one type of non-conjugated olefin unit, and only one type of aromatic vinyl unit, more preferably a ternary copolymer consisting of only one type of conjugated diene unit, only one type of non-conjugated olefin unit, and only one type of diene aromatic vinyl unit, and even more preferably a ternary copolymer consisting of only 1,3-butadiene units, ethylene units, and styrene units. Here, "only one type of conjugated diene unit" includes conjugated diene units having different bonding modes.

When the copolymer is, for example, a binary copolymer, it is preferable that the content of the conjugated diene unit is more than 0 mol % and not more than 50 mol %, and the content of the non-conjugated olefin unit is 50 mol % or more and less than 100 mol %.
When the copolymer is, for example, a terpolymer, it is preferred that the content of conjugated diene units is 1 to 50 mol %, the content of non-conjugated olefin units is 40 to 97 mol %, and the content of aromatic vinyl units is 2 to 35 mol %.

The copolymer preferably has a polystyrene-equivalent number average molecular weight (Mn) of 10,000 to 9,000,000 (10 to 9,000 kg/mol), more preferably 50,000 to 9,000,000 (50 to 9,000 kg/mol), and even more preferably 100,000 to 8,000,000 (100 to 8,000 kg/mol). By having the Mn of the copolymer of 10,000 or more, the peel strength of the composite can be sufficiently ensured, and by having the Mn of 9,000,000 or less, the workability of the member is not easily impaired.

The copolymer preferably has a polystyrene-equivalent weight average molecular weight (Mw) of 10,000 to 10,000,000 (10 to 10,000 kg/mol), more preferably 50,000 to 9,000,000 (50 to 9,000 kg/mol), and even more preferably 100,000 to 8,000,000 (100 to 8,000 kg/mol). By having the Mw of the copolymer of 10,000 or more, the peel strength of the composite can be sufficiently ensured, and by having the Mw of 10,000,000 or less, the workability of the member is less likely to be impaired.

The molecular weight distribution [Mw/Mn (weight average molecular weight/number average molecular weight)] of the copolymer is preferably 1.00 to 4.00, more preferably 1.00 to 3.50, and even more preferably 1.80 to 3.00. If the molecular weight distribution of the copolymer is 4.00 or less, sufficient homogeneity can be achieved in the physical properties of the copolymer.

The weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw/Mn) of the copolymer are determined by gel permeation chromatography (GPC) using polystyrene as a standard substance.

The copolymer preferably has an endothermic peak energy of 10 to 150 J/g, more preferably 30 to 120 J/g, as measured by a differential scanning calorimeter (DSC) at 0 to 120° C. If the endothermic peak energy of the copolymer is 10 J/g or more, the crystallinity of the copolymer is high, and the peel strength of the composite can be improved. If the endothermic peak energy of the copolymer is 150 J/g or less, the workability of the member is improved.
The endothermic peak energy of the copolymer may be measured by using a differential scanning calorimeter in accordance with JIS K 7121-1987, for example, by increasing the temperature from −150° C. to 150° C. at a rate of 10° C./min.

The copolymer has a melting point, as measured by a differential scanning calorimeter (DSC), of preferably 30 to 130° C., more preferably 50 to 120° C. If the melting point of the copolymer is 50° C. or higher, the crystallinity of the copolymer is high, and the peel strength of the composite can be improved. If the melting point of the copolymer is 120° C. or lower, the workability of the member is improved.
The melting point of the copolymer may be measured using a differential scanning calorimeter in accordance with JIS K 7121-1987.

In addition, from the viewpoint of facilitating adhesion between the components, the difference in melting point between the copolymer components is preferably 30°C or less, more preferably 20°C or less, even more preferably 10°C or less, and particularly preferably 0°C, i.e., each component contains a copolymer with the same melting point. If the difference in melting point between the components is 0°C, adhesion between the components will be even easier.

The copolymer preferably has a glass transition temperature (Tg) measured by a differential scanning calorimeter (DSC) of 0° C. or lower, more preferably −100 to −10° C. If the glass transition point of the copolymer is 0° C. or lower, the peel strength of the composite can be further improved.
The glass transition temperature of the copolymer may be measured using a differential scanning calorimeter in accordance with JIS K 7121-1987.

The copolymer preferably has a crystallinity of 0.5 to 50%, more preferably 3 to 45%, and even more preferably 5 to 45%. If the copolymer has a crystallinity of 0.5% or more, the crystallinity of the copolymer due to the non-conjugated olefin units can be sufficiently ensured, and the peel strength of the composite can be further improved. If the copolymer has a crystallinity of 50% or less, the workability during kneading of the members and the extrusion processability are improved.
The crystallinity of the copolymer can be calculated by measuring the crystalline melting energy of 100% crystalline polyethylene and the melting peak energy of the copolymer, and calculating the crystallinity from the energy ratio between the polyethylene and the copolymer. The melting peak energy can be measured by a differential scanning calorimeter.

The copolymer preferably has a main chain consisting of only acyclic structures, which can further improve the peel strength of the composite.
In addition, NMR is used as a main measurement means for confirming whether the main chain of the copolymer has a cyclic structure or not. Specifically, when no peaks derived from the cyclic structure present in the main chain (for example, peaks appearing at 10 to 24 ppm for three- to five-membered rings) are observed, it indicates that the main chain of the copolymer is composed of only a non-cyclic structure.
In the present invention, the main chain of a polymer means a linear molecular chain in which all other molecular chains (long molecular chains or short molecular chains, or both) are linked like pendants (see Section 1.34 of "Glossary of Basic Terms in Polymer Science IUPAC Recommendations 1996", Pure Appl. Chem., 68, 2287-2311 (1996)).
The copolymer may have either a linear or branched structure, but is preferably a linear structure.

The copolymer has excellent mechanical strength, specifically, excellent breaking strength, puncture strength, tensile strength, abrasion resistance, crack resistance, etc. The copolymer also has excellent mechanical strength at low temperatures.
Furthermore, the copolymer has excellent mechanical strength without relying on fillers such as carbon black, silica, etc., and can be colored with a colorant, leading to excellent decorative properties. On the other hand, the copolymer can interact with a filler, so that the mechanical strength can be further improved by using the filler.
The copolymer contains conjugated diene units, so it can be crosslinked, and the crosslinking speed is the same as that of diene-based rubber. The copolymer contains conjugated diene units, so it acts as an elastic body and is stretchable. The copolymer can be injection molded and stretched, so it can be processed into a film. The copolymer contains conjugated diene units and non-conjugated olefin units, so it is easy to adhere to both olefin resins and rubber, and therefore can function as an adhesive between olefin resins and rubber. The copolymer can be foamed. The copolymer preferably has a melting point of 30 to 130°C, more preferably 50 to 120°C, and can be restored to its shape by heating it to the extent that hot water of about 80 to 100°C is poured on it or it is immersed in hot water. The copolymer also has shape memory properties.

When producing a binary copolymer consisting of two units, a conjugated diene unit and a non-conjugated olefin unit, as the copolymer, the copolymer can be produced through a polymerization process using a conjugated diene compound and a non-conjugated olefin compound as monomers.
When a terpolymer consisting of three units, a conjugated diene unit, a non-conjugated olefin unit, and an aromatic vinyl unit, is produced as the copolymer, the copolymer can be produced through a polymerization process using a conjugated diene compound, a non-conjugated olefin compound, and an aromatic vinyl compound as monomers.

The method for producing the copolymer may further include a coupling step, a washing step, and other steps, if necessary.
The method for producing the copolymer will be described below by taking the case of producing a terpolymer as a representative example.

In the production of polymers, it is preferable to add only the non-conjugated olefin compound and the aromatic vinyl compound in the presence of a polymerization catalyst, without adding the conjugated diene compound, and polymerize them first. In particular, when using the catalyst composition described below, it is difficult to polymerize either or both of the non-conjugated olefin compound and the aromatic vinyl compound in the presence of the conjugated diene compound, since the conjugated diene compound has a higher reactivity than the non-conjugated olefin compound and the aromatic vinyl compound. In addition, due to the characteristics of the catalyst, it is also difficult to polymerize the conjugated diene compound first and then additionally polymerize the non-conjugated olefin compound and the aromatic vinyl compound.

As a polymerization method, any method such as solution polymerization, suspension polymerization, liquid phase bulk polymerization, emulsion polymerization, gas phase polymerization, solid phase polymerization, etc. can be used. In addition, when a solvent is used in the polymerization reaction, the solvent may be any solvent that is inert in the polymerization reaction, such as toluene, cyclohexane, normal hexane, etc.

The polymerization step may be carried out in one stage or in two or more stages.
The one-stage polymerization process is a process in which all types of monomers to be polymerized, i.e., a conjugated diene compound, a non-conjugated olefin compound, an aromatic vinyl compound, and other monomers, preferably a conjugated diene compound, a non-conjugated olefin compound, and an aromatic vinyl compound, are reacted and polymerized simultaneously.
A multi-stage polymerization process is a process in which one or two types of monomers are first reacted in part or in whole to form a polymer (first polymerization stage), and then one or more stages (second polymerization stage to final polymerization stage) are carried out in which a type of monomer not added in the first polymerization stage, the remainder of the monomer added in the first polymerization stage, etc. are added and polymerized. In particular, in the production of the copolymer, it is preferable to carry out the polymerization process in multiple stages.

In the polymerization step, the polymerization reaction is preferably carried out under an atmosphere of an inert gas, preferably nitrogen gas or argon gas. The polymerization temperature of the polymerization reaction is not particularly limited, but is preferably in the range of -100°C to 200°C, and can be around room temperature. The pressure of the polymerization reaction is preferably in the range of 0.1 to 10.0 MPa in order to sufficiently incorporate the conjugated diene compound into the polymerization reaction system.
The reaction time of the polymerization reaction is not particularly limited, and is preferably in the range of, for example, 1 second to 10 days, but can be appropriately selected depending on conditions such as the type of polymerization catalyst and polymerization temperature.
In the polymerization step of the conjugated diene compound, the polymerization may be terminated using a polymerization terminator such as methanol, ethanol, isopropanol, or the like.

The polymerization process is preferably carried out in multiple stages. More preferably, a first step is carried out in which a first monomer raw material containing at least an aromatic vinyl compound is mixed with a polymerization catalyst to obtain a polymerization mixture, and a second step is carried out in which a second monomer raw material containing at least one selected from the group consisting of a conjugated diene compound, a non-conjugated olefin compound, and an aromatic vinyl compound is introduced into the polymerization mixture. Furthermore, it is more preferable that the first monomer raw material does not contain a conjugated diene compound, and the second monomer raw material contains a conjugated diene compound.

The first monomer raw material used in the first step may contain a non-conjugated olefin compound together with the aromatic vinyl compound. The first monomer raw material may contain the entire amount of the aromatic vinyl compound used, or may contain only a portion of the aromatic vinyl compound. The non-conjugated olefin compound is contained in at least one of the first monomer raw material and the second monomer raw material.

The first step is preferably carried out in a reactor under an atmosphere of an inert gas, preferably nitrogen gas or argon gas. The temperature (reaction temperature) in the first step is not particularly limited, but is preferably in the range of -100 to 200°C, and can be around room temperature. The pressure in the first step is not particularly limited, but is preferably in the range of 0.1 to 10.0 MPa in order to sufficiently incorporate the aromatic vinyl compound into the polymerization reaction system. The time spent in the first step (reaction time) can be appropriately selected depending on the type of polymerization catalyst, reaction temperature, and other conditions, but is preferably in the range of 5 to 500 minutes, for example, when the reaction temperature is 25 to 80°C.

In the first step, any method such as solution polymerization, suspension polymerization, liquid phase bulk polymerization, emulsion polymerization, gas phase polymerization, and solid phase polymerization can be used as the polymerization method to obtain the polymerization mixture. In addition, when a solvent is used in the polymerization reaction, the solvent may be any solvent that is inert in the polymerization reaction, such as toluene, cyclohexanone, and normal hexane.

The second monomer raw material used in the second step is preferably a conjugated diene compound alone, or a conjugated diene compound and a non-conjugated olefin compound, or a conjugated diene compound and an aromatic vinyl compound, or a conjugated diene compound, a non-conjugated olefin compound and an aromatic vinyl compound.
In addition, when the second monomer raw material contains at least one selected from the group consisting of a non-conjugated olefin compound and an aromatic vinyl compound in addition to the conjugated diene compound, these monomer raw materials may be mixed together with a solvent or the like in advance and then introduced into the polymerization mixture, or each monomer raw material may be introduced individually. In addition, each monomer raw material may be added simultaneously or successively.
In the second step, the method of introducing the second monomer raw material into the polymerization mixture is not particularly limited, but it is preferable to control the flow rate of each monomer raw material and continuously add it to the polymerization mixture (so-called metering). Here, when a monomer raw material that is gaseous under the conditions of the polymerization reaction system (for example, ethylene as a non-conjugated olefin compound under the conditions of room temperature and normal pressure) is used, it can be introduced into the polymerization reaction system at a predetermined pressure.

The second step is preferably carried out in a reactor under an atmosphere of an inert gas, preferably nitrogen gas or argon gas. The temperature (reaction temperature) in the second step is not particularly limited, but is preferably in the range of -100 to 200°C, and can be about room temperature. If the reaction temperature is increased, the selectivity of the cis-1,4 bond in the conjugated diene unit may decrease. The pressure in the second step is not particularly limited, but is preferably in the range of 0.1 to 10.0 MPa in order to sufficiently incorporate monomers such as conjugated diene compounds into the polymerization reaction system. The time spent in the second step (reaction time) can be appropriately selected depending on conditions such as the type of polymerization catalyst and the reaction temperature, but is preferably in the range of 0.1 hours to 10 days, for example.
In the second step, the polymerization may be terminated using a polymerization terminator such as methanol, ethanol, or isopropanol.

Here, the polymerization step of the above-mentioned conjugated diene compound, non-conjugated olefin compound, and aromatic vinyl compound preferably includes a step of polymerizing various monomers in the presence of one or more of the following components (a) to (f) as a catalyst component. Note that, in the polymerization step, it is preferable to use one or more of the following components (a) to (f), but it is more preferable to use a combination of two or more of the following components (a) to (f) as a catalyst composition.
Component (a): a rare earth compound or a reaction product of the rare earth compound and a Lewis base Component (b): an organometallic compound Component (c): an aluminoxane Component (d): an ionic compound Component (e): a halogen compound Component (f): a cyclopentadiene skeleton-containing compound selected from substituted or unsubstituted cyclopentadiene (a compound having a cyclopentadienyl group), substituted or unsubstituted indene (a compound having an indenyl group), and substituted or unsubstituted fluorene (a compound having a fluorenyl group) The above components (a) to (f) can be used in the polymerization step, for example, by referring to International Publication No. 2018/092733.

The coupling step is a step of carrying out a reaction (coupling reaction) for organizing at least a part (for example, an end) of the polymer chain of the copolymer obtained in the polymerization step.
In the coupling step, it is preferable to carry out the coupling reaction when the polymerization reaction reaches 100%.
The coupling agent used in the coupling reaction is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include tin-containing compounds such as bis(1-octadecylmaleate)dioctyltin(IV), isocyanate compounds such as 4,4'-diphenylmethane diisocyanate, alkoxysilane compounds such as glycidylpropyltrimethoxysilane, etc. These may be used alone or in combination of two or more.
Among these, bis(1-octadecylmaleate)dioctyltin(IV) is preferred in terms of reaction efficiency and low gel formation.
By carrying out the coupling reaction, the number average molecular weight (Mn) of the copolymer can be increased.

The washing step is a step of washing the copolymer obtained in the polymerization step.
The medium used for washing is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include methanol, ethanol, and isopropanol. When a catalyst derived from a Lewis acid is used as a polymerization catalyst, an acid (e.g., hydrochloric acid, sulfuric acid, nitric acid, etc.) can be added to these solvents. The amount of acid added is preferably 15 mol% or less relative to the solvent. By adding an amount of 15 mol% or less, the acid is unlikely to remain in the copolymer and is unlikely to adversely affect the reaction during kneading and vulcanization of the member.
This washing step makes it possible to suitably reduce the amount of catalyst residue in the copolymer.

From the viewpoint of improving the peel strength of the composite and further facilitating adhesion between the components, the content of the copolymer in the component is preferably 0.1 to 25% by mass, more preferably 0.1 to 23% by mass, even more preferably 0.2 to 20% by mass, and even more preferably 0.2 to 15% by mass.

<Rubber component>
At least one of the members may include a rubber component.
The rubber component includes natural rubber (NR) and diene rubbers such as synthetic diene rubbers.
Specific examples of synthetic diene rubbers include polyisoprene rubber (IR), polybutadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), chloroprene rubber (CR), halogenated butyl rubber, and acrylonitrile-butadiene rubber (NBR).
The diene rubber may be used alone or in combination of two or more kinds. The diene rubber may be modified.
The rubber component may contain a non-diene rubber.

The content of the rubber component in the member is preferably 40% by mass or more and 70% by mass or less.
The content of the diene rubber in the member is preferably 50% by mass or more and 70% by mass or less.

<Asphalt components>
At least one of the members may contain an asphalt component. The asphalt component is not particularly limited, and examples thereof include natural asphalt such as straight asphalt for paving, lake asphalt, semi-blown asphalt, straight asphalt modified with blown asphalt, and straight asphalt modified with tar.
The content of the asphalt component in the member is preferably 3% by mass or more and 20% by mass or less.

<Aggregate>
When the member contains an asphalt component, the member preferably further contains aggregate, such as crushed stone, sand, slag, etc.
The content of the aggregate in the member is preferably 500% by mass or more and 1000% by mass or less, based on the mass of the asphalt component.

An example of a member containing the asphalt component and the aggregate is a paved road. In addition, when a member that is to be joined to a member containing the asphalt component and the aggregate (such as a paved road) is a member containing a rubber component, preferably a member containing 50 mass% or more of diene rubber, an example of such a member is wear powder from rubber products such as tires. Here, by joining wear powder from rubber products such as tires (members containing rubber components) to a paved road (members containing the asphalt component and the aggregate), dust caused by wear powder can be reduced.

<Resin Component>
At least one of the members may contain a resin component, and the content of the resin component in the member is preferably 1% by mass or more and 15% by mass or less.
The resin may be an olefin-based resin.

(Olefin resin)
The member constituting the composite of the present invention may further contain an olefin-based resin.
By including an olefin-based resin in the member, the peel strength of the composite can be further improved compared to a case in which the member includes only the copolymer.

The olefin resin refers to a resin in which at least polyolefin has crystallinity and constitutes the main part of the resin. For example, olefin-α-olefin copolymers, olefin copolymers, etc. may be mentioned, and may be modified.
Specifically, polyethylene, ethylene-propylene copolymer, ethylene-hexene copolymer, ethylene-pentene copolymer, ethylene-octene copolymer, propylene-1-hexene copolymer, ethylene-4-methyl-pentene copolymer, propylene-4-methyl-1-pentene copolymer, ethylene-butene copolymer, propylene-butene copolymer, 1-butene-hexene copolymer, 1-butene-4-methyl-pentene copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene Examples of the polymer include propylene-butyl methacrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-butyl acrylate copolymer, ethylene-vinyl acetate copolymer, propylene-methacrylic acid copolymer, propylene-methyl methacrylate copolymer, propylene-ethyl methacrylate copolymer, propylene-butyl methacrylate copolymer, propylene-methyl acrylate copolymer, propylene-ethyl acrylate copolymer, propylene-butyl acrylate copolymer, and propylene-vinyl acetate copolymer.

The olefin resin preferably contains a non-conjugated olefin unit, which provides excellent peel strength.
The olefin resin preferably contains an olefin unit having 2 to 5 carbon atoms, and further preferably, the difference between the carbon number of the non-conjugated olefin unit contained in the copolymer and the carbon number of the non-conjugated olefin unit contained in the olefin resin is 2 or less.
The copolymer and the olefin resin contain non-conjugated olefin units, which are units common to both copolymers and olefin resins, and the non-conjugated olefin units have similar structures, so that the members are less susceptible to cracking and also have excellent peel strength.

The difference between the number of carbon atoms of the non-conjugated olefin units contained in the copolymer and the number of carbon atoms of the non-conjugated olefin units contained in the olefin-based resin is more preferably 1 or less, and even more preferably 0. The number of carbon atoms of the olefin units is more preferably 2 to 4, and even more preferably 2 to 3, that is, polyethylene-based resins and polypropylene-based resins.

The polyethylene-based resin means a polymer containing ethylene units as a main component (e.g., more than 50 mol%) in the main chain, and may further contain other units such as propylene units. The polyethylene-based resin may be either thermosetting or thermoplastic. Specific examples include polyethylene (homopolymer), ethylene-propylene copolymer (wherein the ethylene unit is more than 50 mol%), and the like.
In addition, there are various types of polyethylene resins, such as very low density polyethylene (VLDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), and high density polyethylene (HDPE), and any of these may be used.

Among these, due to their high versatility, it is preferable to use one or more polyethylene resins selected from the group consisting of high density polyethylene (HDPE) and linear low density polyethylene (LLDPE).

A polypropylene-based resin refers to a polymer containing propylene units as the main component (e.g., more than 50 mol%) in the main chain, and may further contain other units such as ethylene units. In addition, polypropylene-based resins may be thermosetting or thermoplastic. Specific examples include polypropylene (homopolymer), ethylene-propylene copolymer (wherein propylene units are more than 50 mol%), etc.

From the viewpoint of improving the peel strength of the composite, the olefin resin preferably has a number average molecular weight (Mn) in terms of polystyrene of 5 to 10,000 kg/mol, more preferably 7 to 1,000 kg/mol, and even more preferably 10 to 1,000 kg/mol.

From the viewpoint of improving the peel strength of the composite, the weight average molecular weight (Mw) of the olefin resin is preferably from 100 to 300 kg/mol, more preferably from 180 to 300 kg/mol, and even more preferably from 200 to 280 kg/mol.
The number average molecular weight (Mn) and weight average molecular weight (Mw) of the olefin resin can be measured by gel permeation chromatography (GPC). For example, a GPC (gel permeation chromatography) such as "HLC-8321GPC/HT" manufactured by Tosoh Corporation can be used.

(Other resins)
Examples of the resin other than the olefin resin include polyamide resins, polyester plastic elastomers, and polyester resins such as polybutylene terephthalate and polybutylene naphthalate. These may be used alone or in combination of two or more.

<Various ingredients>
The member may further contain polymer components other than the copolymer, rubber component, asphalt component, and resin component, and may be blended with various components generally used in the resin and rubber fields, such as fillers, reinforcing fibers, antioxidants, softeners, crosslinking packages containing stearic acid, zinc oxide, crosslinking accelerators, and crosslinking agents, resins, ultraviolet absorbers, foaming agents, and colorants, as appropriate, within a range that does not impair the object of the present invention. Commercially available products can be suitably used as these various components.

(Filler)
Fillers include carbon black and inorganic fillers.
When the member contains a rubber component, the further inclusion of a filler can improve the mechanical strength of the vulcanized rubber and the peel strength of the composite.
The type of carbon black is not particularly limited, and examples thereof include GPF, FEF, HAF, ISAF, SAF, and the like, with HAF, ISAF, and SAF being preferred.
Examples of inorganic fillers include metal oxides such as silica, alumina, and titania, and among these, silica is preferred.The type of silica is not particularly limited, and examples thereof include wet silica (hydrated silicic acid), dry silica (anhydrous silicic acid), and colloidal silica.When silica is contained as a filler, the member of the present invention may further contain a silane coupling agent in order to improve the dispersibility of silica in the member of the present invention.

(Anti-aging agent)
Examples of the antioxidant include amine-ketone compounds, imidazole compounds, amine compounds, phenol compounds, sulfur compounds, and phosphorus compounds.

(Softener)
Examples of the softener include petroleum-based softeners such as process oil, lubricating oil, naphthenic oil, paraffin, liquid paraffin, petroleum asphalt, and vaseline, fatty oil-based softeners such as castor oil, linseed oil, rapeseed oil, and coconut oil, and waxes such as beeswax, carnauba wax, and lanolin. These softeners may be used alone or in combination of two or more.

(Crosslinking Agent)
The crosslinking agent is not particularly limited, and typically includes peroxides, sulfur, oximes, amines, ultraviolet curing agents, and the like.
Since the copolymer contains conjugated diene units, it can be crosslinked (vulcanized) with sulfur, such as powdered sulfur, precipitated sulfur, colloidal sulfur, surface-treated sulfur, insoluble sulfur, etc.

(Crosslinking Accelerator)
When the members constituting the composite of the present invention contain a rubber component, they may contain a crosslinking accelerator (vulcanization accelerator) to accelerate vulcanization of the rubber component.
Examples of the vulcanization accelerator include guanidine-based, sulfenamide-based, thiuram-based, thiazole-based, aldehyde-based, and thiocarbamate-based accelerators.

<Method of manufacturing the components>
The method for producing the member is not particularly limited and can be appropriately selected depending on the member. For example, the copolymer and other materials may be mixed, heated, and molded.
The member may be manufactured by containing any additive component as long as it contains the copolymer, for example, a rubber component may be contained together with the copolymer.

<Method of Manufacturing the Composite>
A method for producing a composite according to one embodiment of the present invention (hereinafter, sometimes referred to as the "production method of the present embodiment") is a method for producing a composite consisting of at least two members,
contacting at least two members;
and heating at least two members in contact to bond and secure them together.
According to the manufacturing method of this embodiment, a composite body having improved peel strength and in which members can be easily bonded to each other can be obtained.

The method for producing the composite of this embodiment may include steps other than those described above as appropriate.

(Step of Contacting Members)
The manufacturing method of this embodiment includes a step of contacting at least two members.
In the step of contacting the members, at least two members are contacted.
The method of contacting the members is not particularly limited as long as the members are in contact with each other.
The time for which the members are in contact with each other is not particularly limited and can be appropriately selected depending on the purpose.

(The process of heating, bonding, and fixing the components)
The manufacturing method of this embodiment includes a step of heating at least two members in contact with each other to bond and fix them.
The heating temperature when heating the members is not particularly limited as long as the members can be bonded to each other, and can be appropriately selected depending on the purpose. For example, the heating temperature may be 100 to 500° C.
The heating time is not particularly limited as long as it is possible to bond the members together, and can be appropriately selected depending on the purpose. For example, the heating time may be 1 to 200 seconds.
The heating method is not particularly limited and can be appropriately selected depending on the purpose.
In the manufacturing method of this embodiment, after heating, the members are cooled to fix the at least two members.
The cooling temperature in the immobilization is not particularly limited and can be appropriately selected depending on the purpose. The cooling temperature may be, for example, room temperature.

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

(Preparation of Copolymer 1)
Into a thoroughly dried 2000 mL pressure-resistant stainless steel reactor, 75 g of styrene and 675 g of toluene were placed.
Meanwhile, in a glove box under a nitrogen atmosphere, 0.075 mmol of ((1-benzyldimethylsilyl-3-methyl)indenyl)bis(bis(dimethylsilyl)amide)gadolinium complex {(1-BnMe ₂ Si-3-Me]C ₉ H ₅ Gd[N(SiHMe ₂ ) ₂ ] ₂ }, 0.083 mmol of dimethylanilinium tetrakis(pentafluorophenyl)borate [Me ₂ NHPhB(C ₆ F ₅ ) ₄ ], and 0.35 mmol of diisobutylaluminum hydride were added to a glass container, and 30 g of toluene was further added to prepare a catalyst solution.
The obtained catalyst solution was added to the pressure-resistant stainless steel reactor and heated to 60°C.
Next, ethylene was introduced into the pressure-resistant stainless steel reactor at a pressure of 1.5 MPa, and copolymerization was carried out for a total of 3 hours at 75° C. During the copolymerization, 80 g of a toluene solution containing 20 g of 1,3-butadiene was continuously added at a rate of 0.4 to 0.6 mL/min.
Next, 1 mL of a 5% by mass solution of 2,2'-methylene-bis(4-ethyl-6-t-butylphenol) (NS-5) in isopropanol was added to the pressure-resistant stainless steel reactor to terminate the reaction.
Next, the copolymer was separated using a large amount of methanol and dried in vacuum at 50° C. to obtain Copolymer 1.

(Preparation of Copolymer 2)
Into a thoroughly dried 2000 mL pressure-resistant stainless steel reactor, 30 g of styrene, 20 g of a toluene solution containing 5 g of 1,3-butadiene, and 430 g of toluene were placed.
Meanwhile, in a glove box under a nitrogen atmosphere, 0.075 mmol of mono(1,3-bis(tert-butyldimethylsilyl)indenyl)bis(bis(dimethylsilyl)amide)gadolinium complex {1,3-[(t-Bu)Me ₂ Si] ₂ C ₉ H ₅ Gd[N(SiHMe ₂ ) ₂ ] ₂ }, 0.075 mmol of dimethylanilinium tetrakis(pentafluorophenyl)borate [Me ₂ NHPhB(C ₆ F ₅ ) ₄ ], and 0.35 mmol of diisobutylaluminum hydride were added to a glass container, and 20 mL of toluene was further added to prepare a catalyst solution.
The obtained catalyst solution was added to the pressure-resistant stainless steel reactor and heated to 60°C.
Next, ethylene was introduced into the pressure-resistant stainless steel reactor at a pressure of 1.0 MPa, and copolymerization was carried out for a total of 3 hours at 75° C. During the copolymerization, 240 g of a toluene solution containing 60 g of 1,3-butadiene was continuously added at a rate of 2.5 to 2.8 mL/min.
Next, 1 mL of a 5% by mass solution of 2,2'-methylene-bis(4-ethyl-6-t-butylphenol) (NS-5) in isopropanol was added to the pressure-resistant stainless steel reactor to terminate the reaction.
Next, the copolymer was separated using a large amount of methanol and dried in vacuum at 50° C. to obtain Copolymer 2.

<Method of Measuring Physical Properties of Copolymers 1 and 2>
The following physical properties were measured for the resulting Copolymers 1 and 2. The results are shown in Table 1.

(1) Contents of Butadiene Units, Ethylene Units, and Styrene Units The contents (mol %) of ethylene units, butadiene units, and styrene units in the copolymer were determined from the integral ratio of each peak in ¹ H-NMR spectrum (100° C., d-tetrachloroethane standard: 6 ppm).

(2) Number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw/Mn)
Monodisperse polystyrene was analyzed by gel permeation chromatography [GPC: Tosoh HLC-8121GPC/HT, column: Tosoh GMH _HR -H(S)HT x 2, detector: differential refractometer (RI)]. As a standard, the number average molecular weight (Mn), weight average molecular weight (Mw), and molecular weight distribution (Mw/Mn) of the copolymer were determined in terms of polystyrene. The measurement time was 40°C.

(3) Content of 1,4-bonds in butadiene units 1,2-bonds and 3,4-bonds were determined by an infrared method (Morello method), and the content of 1,4-bonds was calculated by calculating the total amount of 1,2-bonds and 3,4-bonds from 100%.

(4) Melting point (Tm)
The melting point (Tm) of the copolymer was measured using a differential scanning calorimeter (DSC, manufactured by TA Instruments Japan, "DSCQ2000") in accordance with JIS K 7121-1987.

(5) Glass transition temperature (Tg)
The glass transition temperature (Tg) of the copolymer was measured using a differential scanning calorimeter (DSC, manufactured by TA Instruments Japan, "DSCQ2000") in accordance with JIS K 7121-1987.

(6) Crystallinity The crystalline melting energy of 100% crystalline polyethylene and the melting peak energy of the resulting copolymer at 0 to 120° C. were measured, and the crystallinity was calculated from the energy ratio between the polyethylene and the copolymer. The melting peak energy was measured with a differential scanning calorimeter (DSC, manufactured by TA Instruments Japan, "DSCQ2000").

(7) Endothermic Peak Energy Using a differential scanning calorimeter (DSC, manufactured by TA Instruments Japan, "DSCQ2000"), in accordance with JIS K 7121-1987, the obtained copolymer was heated from -150°C to 150°C at a rate of 10°C/min. Then, the endothermic peak energy (ΔH ₁ (J/g)) in the range of 0°C or more and less than 100°C and the endothermic peak energy (ΔH ₂ (J/g)) in the range of 100°C or more and 150°C or less at that time (1st run) were measured.

(8) Tensile Strength Copolymers 1 and 2 were hot pressed at 145° C. to produce sheets having a thickness of 1 mm, and the tensile strength (Tb; Tensile Strength at break) was measured.
The tensile strength (Tb) was measured based on JIS K 6251 (2017) using a tensile testing device (manufactured by Instron) by elongating the test piece by 100% at 25°C, and the maximum tensile force required to break the test piece was measured.

(9) Elongation at break Copolymers 1 and 2 were hot pressed at 145° C. to produce sheets having a thickness of 1 mm, and the elongation at break (Eb) was measured.
The breaking elongation (Eb) was determined by measuring the length at which the test piece broke when it was pulled at 25° C. at a rate of 100 mm/min, and expressing this length as a percentage of the length (100%) before pulling.

<Production of the Complex>
At least two components of the composite were a component containing a rubber component and a component containing an asphalt component.

(Preparation of members containing rubber components)
A rubber composition was prepared by blending, kneading, and vulcanizing each component according to the compounding recipe shown in Table 2. The types and amounts of the blended copolymers having conjugated diene units and non-conjugated olefin units are as shown in Table 3 or Table 4. This rubber composition was abraded to obtain abrasion powder having a major axis of 0.1 to 20 mm, which was used as a member containing a rubber component.

＊１ ＮＲ： 天然ゴム
＊２ ＢＲ： ブタジエンゴム、ＵＢＥエラストマー社製、商品名「ＵＢＥＰＯＬ ＢＲ１５０Ｌ」
＊３ カーボンブラック： Ｎ１３４
＊４ 加硫系薬品： 加硫促進剤と硫黄を含む
＊５ その他成分： ステアリン酸、亜鉛華を含む

*1 NR: Natural rubber *2 BR: Butadiene rubber, manufactured by UBE Elastomers, product name "UBEPOL BR150L"
*3 Carbon black: N134
*4 Vulcanization chemicals: Contains vulcanization accelerators and sulfur *5 Other ingredients: Contains stearic acid and zinc oxide

(Preparation of components containing asphalt components)
Copolymer 1 or 2 (shown in Tables 3 and 4) was added to asphalt (straight asphalt 60/80, manufactured by ENEOS Corporation) and mixed using a homomixer to prepare a composition. Then, aggregate (manufactured by Tokyo Sekiryu Kogyo Co., Ltd.) was mixed with the composition to prepare an asphalt mixture, which was used as a member containing an asphalt component.
In the preparation of the asphalt mixture, the content of the above composition in the asphalt mixture was set to 5.4% by mass. Therefore, the content of the copolymer in the member containing the asphalt component was calculated to be 0.27% by mass, as shown in Tables 3 and 4.

(Preparation of Complex)
The above two members were joined together, and then heated at 120° C. for 120 seconds using a vulcanizing press heated to a predetermined temperature. After that, the members were cooled at room temperature and fixed to prepare a composite.
The amount of copolymer contained in the members in each of the examples and comparative examples is shown in Tables 3 and 4.

(Peel test)
An adhesive tape was applied to the above-mentioned fixed composite, and the tape was peeled off to evaluate the peel strength based on the amount of the rubber component-containing material adhered to the tape. The peel strength was evaluated according to the following criteria. The less adhesion to the adhesive tape, the greater the peel strength.
A: Slight adhesion to the adhesive tape. B: A small amount of adhesion to the adhesive tape. C: A large amount of adhesion to the adhesive tape. D: Almost all adhesion to the adhesive tape. The evaluation results are shown in Tables 3 and 4.

From Tables 3 and 4, it can be seen that the peel strength is improved by including a copolymer in each component that constitutes the composite. Furthermore, even if each component is made of a different material, they can be easily bonded by the process of the present invention.

According to the present invention, a composite body having improved peel strength and easy adhesion can be provided.

Claims (11)

A composite of at least two members,
The at least two members are joined together,
The joined parts are made of different materials,
The composite, wherein the at least two components both contain a copolymer having conjugated diene units and non-conjugated olefin units. The composite according to claim 1, wherein the melting point of the copolymer is 50 to 120°C. The composite according to claim 1, wherein the copolymer has a content of the conjugated diene units of more than 0 mol% and not more than 50 mol%, and a content of the non-conjugated olefin units of 50 mol% or more and less than 100 mol%. The composite of claim 1, wherein the copolymer further comprises an aromatic vinyl unit. The composite according to claim 4, wherein the copolymer has a conjugated diene unit content of 1 to 50 mol%, a non-conjugated olefin unit content of 40 to 97 mol%, and an aromatic vinyl unit content of 2 to 35 mol%. The composite according to claim 1, wherein the content of the copolymer in each of the components is 0.1 to 25% by mass. The composite of claim 1, wherein the difference in melting point of the copolymer between the members is 30°C or less. The composite according to claim 1, wherein at least one of the at least two components contains 3 to 20% by mass of the copolymer and 50% by mass or more of a diene rubber. The composite of claim 1, wherein at least one of the components contains 0.1 to 10% by mass of the copolymer and an asphalt component. The composite of claim 1, wherein at least one of the members contains 50% by mass or more of a resin component. A method for producing the composite according to claim 1, comprising the steps of:
contacting the at least two members;
and heating the at least two members in contact to bond and fix them together.