JP7709953B2 - Modified Hydrogenated Block Copolymer - Google Patents

Description

The present invention aims to provide a modified hydrogenated block copolymer that is soluble in organic solvents, has transparency, rigidity and heat resistance, and has excellent adhesion to substrates such as metals.

In general, polyolefins such as polyethylene and polypropylene are lightweight, water-resistant, chemical-resistant, insulating, and easy to handle, and therefore are given shapes through various molding processes and are used as various industrial materials.
In addition, since polyolefins are mainly composed of carbon and hydrogen, it is generally difficult to composite them with other materials, such as metals and glass, and various inventions have been made to improve their adhesive properties.
In particular, modification by acid modification with an organic carboxylic acid or an anhydride thereof has dramatically improved the thermal adhesiveness to metals (Patent Documents 1 and 2).

On the other hand, polyolefins have high chemical resistance and are difficult to dissolve in various organic solvents, so industrial use of the solution is generally difficult. For this reason, various inventions have been made to improve the solvent solubility of acid-modified polyolefins (Patent Documents 3 to 5).

Japanese Patent Application Publication No. 3-166283 International Publication No. 2018/180862 JP 2004-217807 A JP 2017-197651 A JP 2003-012720 A

Polyolefins or acid-modified polyolefins are crystalline resins, and the crystals are the cause of the reduced solubility in organic solvents. Furthermore, such crystallinity usually impairs the transparency of polyolefins, and the transparency and color development of the coating film are not favorable. For this reason, the above-mentioned inventions have been conducted to reduce the crystallinity of polyolefins and improve their solubility.
However, even with these methods, the solubility is insufficient, and the polyolefins obtained tend to be soft, which may result in reduced heat resistance or sticky coating surfaces.

This tendency of polyolefins to soften can be useful as an adhesive when sandwiched between two adherends, but is often not useful in terms of general laminates or coatings. Also, in order to improve solubility, inventions have been made to chlorinate polyolefins, but the chlorination method is not simple and problems arise in terms of transparency and the generation of harmful gases during combustion.

As described above, there is a demand for materials that are transparent and heat resistant, have a non-sticky surface, can be easily coated or laminated onto an adherend, and suppress the generation of toxic gases when burned.
The present invention has been made in view of the above problems. That is, an object of the present invention is to provide polyolefins which are soluble in organic solvents, have transparency, rigidity, and heat resistance, have excellent adhesion to substrates such as metals, and suppress the generation of toxic gases during combustion.

The present inventors have conducted intensive research to solve the above-mentioned problems, and as a result, have found that the above-mentioned problems can be solved by using a specific hydrogenated block copolymer as a polyolefin and modifying this with an unsaturated carboxylic acid and/or an unsaturated carboxylic acid anhydride.
That is, the present invention has the following features.

[1] A modified hydrogenated block copolymer, which is a hydrogenated block copolymer modified with an unsaturated carboxylic acid and/or an unsaturated carboxylic acid anhydride, the hydrogenated block copolymer being a hydrogenated copolymer comprising a polymer block consisting of aromatic vinyl monomer units and a polymer block consisting of conjugated diene monomer units, the hydrogenated polymer block consisting of aromatic vinyl monomer units being a hydrogenated aromatic vinyl polymer block unit having a hydrogenation level of 90% or more, and the hydrogenated polymer block consisting of conjugated diene monomer units being a hydrogenated conjugated diene polymer block unit having a hydrogenation level of 95% or more.

[2] The modified hydrogenated block copolymer according to [1], wherein the hydrogenated block copolymer has at least two of the hydrogenated aromatic vinyl polymer block units and at least one of the hydrogenated conjugated diene polymer block units.
[3] The modified hydrogenated block copolymer according to [1] or [2], wherein the degree of modification with the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride is 0.1 to 2 mass%.
[4] The modified hydrogenated block copolymer according to any one of [1] to [3], wherein the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride is maleic anhydride.

[5] The modified hydrogenated block copolymer according to any one of [1] to [4], having a weight average molecular weight (Mw) of 5,000 to 100,000.
[6] A modified hydrogenated block copolymer solution or a modified hydrogenated block copolymer slurry, in which the modified hydrogenated block copolymer according to any one of [1] to [5] is dissolved or suspended in an organic solvent at a concentration of 1 to 30 mass %.
[7] A modified hydrogenated block copolymer-containing laminate, comprising the modified hydrogenated block copolymer according to any one of [1] to [5] laminated on a substrate.

[8] The modified hydrogenated block copolymer-containing laminate according to [7], which is obtained by melt co-extrusion molding the modified hydrogenated block copolymer with one or more other thermoplastic resins.
[9] The modified hydrogenated block copolymer-containing laminate according to [7], wherein the modified hydrogenated block copolymer is thermally laminated onto a metal, paper, ceramics, thermoplastic resin, or thermosetting resin.
[10] The modified hydrogenated block copolymer-containing laminate according to [9], wherein the layer containing the modified hydrogenated block copolymer has a thickness of 5 to 500 μm.

[11] A method for producing the modified hydrogenated block copolymer according to any one of [1] to [5], comprising graft-modifying the hydrogenated block copolymer by any one of melt kneading, reaction in solution, and solid-phase grafting.
[12] A method for producing the modified hydrogenated block copolymer according to any one of [1] to [5], comprising graft-modifying the hydrogenated block copolymer with an unsaturated carboxylic acid and/or an unsaturated carboxylic acid anhydride.

[13] A method for producing a modified hydrogenated block copolymer-containing laminate, comprising applying the modified hydrogenated block copolymer solution or modified hydrogenated block copolymer slurry according to [6] to a substrate, and then removing the solvent to obtain a laminate.
[14] The method for producing a modified hydrogenated block copolymer-containing laminate according to [13], wherein the layer containing the modified hydrogenated block copolymer has a thickness of 1 to 100 μm.

The modified hydrogenated block copolymer of the present invention is soluble in an organic solvent, and when applied to a substrate such as metal, glass, plastic, etc., it becomes a coating film having transparency, rigidity, heat resistance, and good adhesive strength, and a laminate can be obtained. Furthermore, since the modified hydrogenated block copolymer of the present invention is not chlorinated, it does not generate toxic gases when burned.
In addition, the solution or slurry of the present invention can be applied to substrates such as metals, glass, and plastics, and by removing the organic solvent, a coating film having transparency, rigidity, heat resistance, and good adhesive strength is obtained.
Furthermore, the laminate of the present invention is transparent, rigid, heat resistant, and has good adhesive strength to substrates.

The present invention will be described in detail below. However, the following description is an example of an embodiment of the present invention, and the present invention is not limited to the contents of the following description as long as it does not deviate from the gist of the present invention.
In the following, when the expression "~" is used, it is used as an expression including the numerical values or physical property values before and after it.

The modified hydrogenated block copolymer of the present invention is a hydrogenated block copolymer modified with an unsaturated carboxylic acid and/or an unsaturated carboxylic anhydride.

<Hydrogenated Block Copolymer>
The hydrogenated block copolymer used as the raw material for the modified hydrogenated block copolymer of the present invention is a hydrogenated product of a block copolymer containing a polymer block consisting of at least one aromatic vinyl monomer unit and a polymer block consisting of at least one conjugated diene monomer unit, i.e., the hydrogenated block copolymer has hydrogenated aromatic vinyl polymer block units and hydrogenated conjugated diene polymer block units.

The hydrogenated aromatic vinyl polymer block unit is a hydrogenated polymer block consisting of aromatic vinyl monomer units, and the hydrogenation level thereof is as described below.
The hydrogenated conjugated diene polymer block unit is a hydrogenated product of a polymer block consisting of conjugated diene monomer units, and the hydrogenation level thereof is as described below.
The hydrogenated block copolymer has at least two of the hydrogenated aromatic vinyl polymer block units and at least one of the hydrogenated conjugated diene polymer block units.
The hydrogenated block copolymer has excellent transparency and material strength.

In this specification, the term "block" refers to a polymerization segment that is separated into microlayers from a copolymer having structurally or compositionally different polymerization segments. For example, "having at least two block units" means that the hydrogenated block copolymer has at least two polymerization segments that are separated into microlayers.

The aromatic vinyl monomer used as the raw material for the aromatic vinyl monomer unit is a monomer represented by the general formula (1).

Here, R is hydrogen or an alkyl group, and Ar is a phenyl group, a biphenyl group, a halophenyl group, an alkylphenyl group, an alkylhalophenyl group, a naphthyl group, a pyridinyl group, or an anthracenyl group.

The alkyl group may be mono- or polysubstituted with functional groups such as halo, nitro, amino, hydroxy, cyano, carbonyl and carboxyl groups. The alkyl group preferably has 1 to 6 carbon atoms.
The above Ar is preferably a phenyl group or an alkylphenyl group, and more preferably a phenyl group.

Examples of aromatic vinyl monomers include styrene, α-methylstyrene, vinyltoluene (including all isomers, especially p-vinyltoluene), ethylstyrene, propylstyrene, butylstyrene, vinylbiphenyl, vinylnaphthalene, vinylanthracene (all isomers), and mixtures thereof.

The conjugated diene monomer serving as the raw material for the conjugated diene monomer unit is not particularly limited as long as it is a monomer having two conjugated double bonds.
Conjugated diene monomers include, for example, 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2-methyl-1,3 pentadiene and the like, and mixtures thereof.

Polybutadiene, a polymer of 1,3-butadiene, can contain either a 1,2 configuration, which upon hydrogenation gives the equivalent of 1-butene repeat units, or a 1,4 configuration, which upon hydrogenation gives the equivalent of ethylene repeat units.

The hydrogenated polymerizable block composed of the aromatic vinyl monomer or the conjugated diene monomer including 1,3-butadiene is included in the hydrogenated block copolymer used in the present invention. Preferably, the hydrogenated block copolymer is a block copolymer having no functional group.
The term "non-functional" means that the block copolymer does not contain any functional groups, i.e., groups containing elements other than carbon and hydrogen.

A preferred example of the hydrogenated aromatic vinyl polymer block unit is a unit made of hydrogenated polystyrene, and a preferred example of the hydrogenated conjugated diene polymer block unit is a unit made of hydrogenated polybutadiene.
A preferred embodiment of the hydrogenated block copolymer is a hydrogenated triblock or pentablock copolymer of styrene and butadiene, which preferably does not contain any other functional groups or structural modifiers.

The content of the hydrogenated aromatic vinyl polymer block unit is preferably 50 to 99 mol %, more preferably 60 to 90 mol %, based on the hydrogenated block copolymer.
When the ratio of the hydrogenated aromatic vinyl polymer block units is equal to or higher than the above lower limit, the rigidity does not decrease, and when it is equal to or lower than the above upper limit, the brittleness does not increase.

The content of the hydrogenated conjugated diene polymer block unit is preferably 1 to 50 mol %, more preferably 10 to 40 mol %, based on the hydrogenated block copolymer.
When the ratio of the hydrogenated conjugated diene polymer block units is equal to or higher than the above lower limit, the brittleness does not deteriorate, and when it is equal to or lower than the above upper limit, the rigidity does not decrease.

The hydrogenated block copolymers of the present invention are produced by hydrogenation of block copolymers including triblock, multiblock, tapered block and star block copolymers such as SBS, SBSBS, SIS, SISIS, and SISBS (where S is polystyrene, B is polybutadiene, and I is polyisoprene).

The hydrogenated block copolymer of the present invention contains a segment made of an aromatic vinyl polymer at each end. Therefore, the hydrogenated block copolymer of the present invention has at least two hydrogenated aromatic vinyl polymer block units. And, between these two hydrogenated aromatic vinyl polymer block units, there is at least one hydrogenated conjugated diene polymer block unit.

The block copolymer before hydrogenation may contain several additional blocks, which may be attached at any position along the triblock polymer backbone. Thus, linear blocks include, for example, SBS, SBSB, SBSBS, and SBSBSB. The copolymer may be branched, and the polymer chains may be attached at any position along the backbone of the copolymer.

The lower limit of the weight average molecular weight (hereinafter abbreviated as "Mw") of the hydrogenated block copolymer is preferably 10,000 or more, more preferably 20,000 or more. The upper limit of Mw is preferably 120,000 or less, more preferably 100,000 or less, even more preferably 95,000 or less, particularly preferably 90,000 or less, most preferably 85,000 or less, and extremely preferably 80,000 or less.
When the Mw is equal to or higher than the lower limit, the mechanical strength does not decrease, and when it is equal to or lower than the upper limit, the solvent solubility of the resulting modified hydrogenated block copolymer is improved.
The Mw of the hydrogenated block copolymer is determined by gel permeation chromatography (GPC), and the specific measurement method is as described in the Examples section.

The hydrogenation level of the hydrogenated aromatic vinyl polymer block unit is preferably 90% or more, more preferably 95% or more, further preferably 98% or more, and particularly preferably 99.5% or more.
The hydrogenation level of the hydrogenated conjugated diene polymer block unit is preferably 95% or more, more preferably 99% or more, and even more preferably 99.5% or more.
Such a high level of hydrogenation is preferred for developing stiffness and heat resistance.

The hydrogenation level of the hydrogenated aromatic vinyl polymer block unit refers to the proportion of the aromatic vinyl polymer block unit saturated by hydrogenation, and the hydrogenation level of the hydrogenated conjugated diene polymer block unit refers to the proportion of the conjugated diene polymer block unit saturated by hydrogenation.
The hydrogenation level is determined using proton NMR.

The melt flow rate (MFR) of the hydrogenated block copolymer of the present invention is usually 0.1 g/10 min or more, preferably 0.5 g/10 min or more from the viewpoint of the molding method and the appearance of the molded product, and usually 200 g/10 min or less, preferably 100 g/10 min or less, more preferably 50 g/10 min or less from the viewpoint of material strength.
The MFR was measured in accordance with ISO R1133 at a measurement temperature of 230° C. and a measurement load of 2.16 kg.

The hydrogenated block copolymers may be used alone or in combination of two or more kinds.
As the hydrogenated block copolymer of the present invention, commercially available products can be used, specifically, ZELAS (registered trademark) manufactured by Mitsubishi Chemical Corporation can be mentioned.

<Modification of hydrogenated block copolymer>
Next, the modification of the hydrogenated block copolymer will be described. This modification is carried out by adding an unsaturated carboxylic acid and/or an unsaturated carboxylic anhydride as a modifier to the hydrogenated block copolymer and reacting the copolymer with the unsaturated carboxylic acid and/or anhydride.

Examples of the unsaturated carboxylic acid and/or unsaturated carboxylic acid anhydride used as the modifying agent include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, α-ethylacrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, and nadic acids, and their anhydrides.
Specific examples of the unsaturated carboxylic acid anhydride include maleic anhydride, citraconic anhydride, and nadic anhydrides.
Examples of nadic acids or their anhydrides include endo-cis-bicyclo[2.2.1]hept-2,3-dicarboxylic acid (nadic acid (trademark)), methyl-endo-cis-bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid (methylnadic acid (trademark)), and their anhydrides.

Among these unsaturated carboxylic acids and/or unsaturated carboxylic acid anhydrides, acrylic acid, maleic acid, nadic acid, maleic anhydride, and nadic acid anhydride are preferred, with maleic anhydride being more preferred.
The unsaturated carboxylic acid and/or unsaturated carboxylic anhydride may be used alone or in combination of two or more kinds.

The hydrogenated block copolymer can be modified with the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride to obtain a modified hydrogenated block copolymer. Suitable methods for modification include solution modification, melt modification, solid-phase modification by irradiation with an electron beam or ionizing radiation, and modification in a supercritical fluid.
Among these, melt modification is preferred because of its excellent equipment and cost competitiveness, and melt kneading modification using an extruder because of its excellent continuous productivity is more preferred.
Examples of the apparatus that can be used in this case include a single screw extruder, a twin screw extruder, a Banbury mixer, and a roll mixer. Among these, a single screw extruder and a twin screw extruder that are excellent in continuous productivity are preferred.

In general, modification of a hydrogenated block copolymer with an unsaturated carboxylic acid and/or an unsaturated carboxylic anhydride is carried out by a graft reaction in which a carbon-hydrogen bond of a hydrogenated conjugated diene polymer block unit, which is one of the block units constituting the hydrogenated block copolymer, is cleaved to generate a carbon radical to which an unsaturated functional group is added.
As a source of carbon radical generation, in addition to the above-mentioned electron beam and ionizing radiation, a method using high temperature and radical generators such as azo compounds, inorganic peroxides, organic peroxides, etc. are also usable. As the radical generator, it is preferable to use an organic peroxide from the viewpoint of cost and operability.

Examples of the azo compound include azobisisobutyronitrile, azobisdimethylvaleronitrile, azobis(2-methylbutyronitrile), and diazonitrophenol.
Examples of the inorganic peroxides include hydrogen peroxide, potassium peroxide, sodium peroxide, calcium peroxide, magnesium peroxide, and barium peroxide.

The organic peroxides include those belonging to the groups of hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxy esters, and ketone peroxides.
Specific examples of the peroxides include hydroperoxides such as cumene hydroperoxide and t-butyl hydroperoxide; dialkyl peroxides such as dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane and 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3; diacyl peroxides such as lauryl peroxide and benzoyl peroxide; peroxy esters such as t-butyl peroxyacetate, t-butyl peroxybenzoate and t-butylperoxyisopropyl carbonate; and ketone peroxides such as cyclohexanone peroxide.
These radical generators may be used alone or in combination of two or more kinds.

The modification by the graft reaction may be, for example, graft modification of the hydrogenated block copolymer by any of the methods of melt kneading, reaction in solution, and solid-phase grafting, or graft modification by the unsaturated carboxylic acid and/or unsaturated carboxylic acid anhydride described above.

[Modification by melt kneading]
The commonly used modification by melt kneading involves blending a hydrogenated block copolymer, an unsaturated carboxylic acid and/or an unsaturated carboxylic anhydride, and an organic peroxide, feeding the mixture into a kneader and extruder, and extruding the mixture while heating, melting and kneading it, and cooling the molten resin emerging from a die at the tip of the die in a water tank or the like to obtain a modified hydrogenated block copolymer.

The blending ratio of the hydrogenated block copolymer to the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride is 0.2 to 5 parts by mass of the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride per 100 parts by mass of the hydrogenated block copolymer.
When the blending ratio of the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride to the hydrogenated block copolymer is equal to or higher than the lower limit, a predetermined modification rate required for achieving the effects of the present invention can be obtained, while when the blending ratio is equal to or lower than the upper limit, no unreacted unsaturated carboxylic acid and/or unsaturated carboxylic anhydride remains, and no adverse effect is caused on the adhesive strength.

The blending ratio of the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride to the organic peroxide is 0.2 to 100 parts by mass of the organic peroxide per 100 parts by mass of the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride.
When the blending ratio of the organic peroxide to the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride is equal to or higher than the lower limit, a desired modification rate required for achieving the effects of the present invention can be obtained, while when the blending ratio is equal to or lower than the upper limit, the hydrogenated block copolymer does not deteriorate and the color does not deteriorate.

As for the melt-kneading modification conditions, for example, it is preferable to extrude at a temperature of 150 to 300°C in a single-screw extruder or twin-screw extruder.

[Denaturation by reaction in solution]
A commonly used modification by reaction in solution involves adding a hydrogenated block copolymer, an unsaturated carboxylic acid and/or an unsaturated carboxylic anhydride, and a radical generator to an organic solvent and heating to obtain a modified hydrogenated block copolymer.

There are no particular restrictions on the organic solvent, so long as it does not have a functional group such as active hydrogen that can react with the radical generator and can dissolve the hydrogenated block copolymer. Examples include benzene, toluene, xylene, chlorobenzene, dichlorobenzene, and t-butylbenzene, and dichlorobenzene is preferred from the standpoint of solubility and stability.

The reaction concentration depends on the solubility of the hydrogenated block copolymer in the organic solvent and the viscosity of the solution, but is preferably 5 to 20% by mass. If the reaction concentration is equal to or higher than the lower limit, the productivity is good, and if it is equal to or lower than the upper limit, the solution viscosity does not increase, and stirring and heat removal are easy.
The blending ratio of the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride, and the radical generator to the hydrogenated block copolymer is the same as in the modification by melt kneading.

The reaction temperature depends on the boiling point of the organic solvent and the half-life temperature of the radical generator used, but is preferably 80 to 150° C. If the reaction temperature is equal to or higher than the lower limit, the reaction rate does not decrease, and if the reaction temperature is equal to or lower than the upper limit, the hydrogenated block copolymer does not decompose, and the reaction is stable.
The reaction time depends on the target graft rate, but is preferably 1 to 10 hours. After the reaction is completed, the reaction product can be recovered by crystallization, filtration, washing, and drying according to known methods.

The crystallization can be performed by lowering the temperature of the reaction solution, increasing the solution concentration by distillation under reduced pressure, or adding a poor solvent to precipitate a solid.
The filtration can be carried out using a filtering device that combines filter paper, filter cloth, etc. Also, a device such as a centrifugal filter, a pressure filter, or a wash and dry filter can be used.

For the washing, it is preferable to use a solvent that does not dissolve the modified hydrogenated block copolymer but dissolves the unreacted unsaturated carboxylic acid and/or unsaturated carboxylic anhydride, specifically, methanol or acetone.
The drying is carried out by removing the residual solvent using a hot air dryer or a reduced pressure dryer.
By these procedures, the modified hydrogenated block copolymer obtained by the reaction in solution can be used for the purpose of the present invention in the same manner as the modification by melt kneading.

Modification by solid-phase grafting
The commonly used modification by solid-phase grafting involves impregnating a hydrogenated block copolymer with an unsaturated carboxylic acid and/or an unsaturated carboxylic anhydride, and a radical generator in a stirrer equipped with a heating jacket, and then carrying out a graft reaction in a temperature range in which the hydrogenated block copolymer does not melt, to obtain a modified hydrogenated block copolymer.
In order to facilitate impregnation, the hydrogenated block copolymer is preferably introduced in a powder state, and the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride are preferably in a liquid state, and in the case of a powder, they are preferably heated to about the melting point and introduced as a liquid.

The temperature of the stirrer is preferably set to a temperature equal to or higher than the melting point of the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride and lower than the glass transition point of the hydrogenated block copolymer. Therefore, the radical generator to be selected is preferably one that is active within the above temperature range.
The reaction proceeds by heating and stirring the mixture, and after completion of the reaction, the modified hydrogenated block copolymer is obtained in a solid state.

[Reduction in molecular weight of modified hydrogenated block copolymer]
When the molecular weight of the modified hydrogenated block copolymer is reduced, the compounding ratio of the modified hydrogenated block copolymer to the organic peroxide is 0.01 to 2 parts by mass of the organic peroxide per 100 parts by mass of the modified hydrogenated block copolymer.
As for the melt kneading and modification conditions, it is preferable to extrude the resin at a temperature of 150 to 300° C. in a single screw extruder or a twin screw extruder.

[Modification rate]
The degree of modification of the modified hydrogenated block copolymer with the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride is preferably from 0.1 to 2% by mass.
If the modification rate is equal to or higher than the lower limit, sufficient adhesive strength can be obtained, whereas if the modification rate is equal to or lower than the upper limit, there is no odor or deterioration in color, and the solubility in organic solvents is good.
The modification ratio of the modified hydrogenated block copolymer is determined using proton NMR after the modified hydrogenated block copolymer is subjected to a methyl esterification treatment.

<Modified hydrogenated block copolymer>
The modified hydrogenated block copolymer of the present invention is a hydrogenated block copolymer modified with an unsaturated carboxylic acid and/or an unsaturated carboxylic anhydride.
The hydrogenated block copolymer is a hydrogenated product of a copolymer containing a polymer block composed of aromatic vinyl monomer units and a polymer block composed of conjugated diene monomer units.
The hydrogenated product of the polymer block composed of the aromatic vinyl monomer unit is a hydrogenated aromatic vinyl polymer block unit having a hydrogenation level of 90% or more, and the hydrogenated product of the polymer block composed of the conjugated diene monomer unit is a hydrogenated conjugated diene polymer block unit having a hydrogenation level of 95% or more.

The hydrogenation level of the hydrogenated aromatic vinyl polymer block unit is preferably 95% or more, more preferably 98% or more, and even more preferably 99.5% or more.
The hydrogenation level of the hydrogenated conjugated diene polymer block unit is preferably 99% or more, more preferably 99.5% or more.
Such a high level of hydrogenation is preferred for developing stiffness and heat resistance.
Here, the meaning of the hydrogenation level and the method for determining the hydrogenation level are the same as those described in the section on hydrogenated block copolymers.

The hydrogenated block copolymer has at least two of the hydrogenated vinyl aromatic polymer block units and at least one of the hydrogenated conjugated diene polymer block units.
The content of the hydrogenated aromatic vinyl polymer block unit is preferably 50 to 99 mol %, more preferably 60 to 90 mol %, based on the modified hydrogenated block copolymer.
When the ratio of the hydrogenated aromatic vinyl polymer block units is equal to or higher than the above lower limit, the rigidity does not decrease, and when it is equal to or lower than the above upper limit, the brittleness does not increase.

The content of the hydrogenated conjugated diene polymer block unit is preferably 1 to 50 mol %, more preferably 10 to 40 mol %, based on the modified hydrogenated block copolymer.
When the ratio of the hydrogenated conjugated diene polymer block units is equal to or higher than the above lower limit, the brittleness does not deteriorate, and when it is equal to or lower than the above upper limit, the rigidity does not decrease.

The lower limit of the Mw of the modified hydrogenated block copolymer is preferably 5,000 or more, more preferably 10,000 or more. The upper limit of the Mw is preferably 100,000 or less, more preferably 80,000 or less. Specifically, 5,000 or more and 100,000 or less is preferred, 5,000 or more and 80,000 or less, or 10,000 or more and 100,000 or less is more preferred, and 10,000 or more and 80,000 or less is even more preferred.

It is preferable that the Mw of the modified hydrogenated block copolymer is equal to or greater than the lower limit, since the material strength, adhesiveness, and heat resistance are not decreased, whereas it is preferable that the Mw is equal to or less than the upper limit, since the solubility in organic solvents is not decreased.
The Mw of the modified hydrogenated block copolymer is determined by GPC measurement.

The Mw of the modified hydrogenated block copolymer can be controlled by the amount of organic peroxide used in modifying the hydrogenated block copolymer.
The modification procedure of the hydrogenated block copolymer is as described above. In addition, similarly to the modification procedure of the hydrogenated block copolymer, an organic peroxide may be further added to the modified hydrogenated block copolymer, the mixture may be blended, and the mixture may be charged into a kneader or an extruder, and extruded while being heated, melted, and kneaded, thereby obtaining a modified hydrogenated block copolymer with a changed Mw.

When the hydrogenated block copolymer or modified hydrogenated block copolymer is treated with an organic peroxide, the carbon-hydrogen bond of the hydrogenated conjugated diene polymer block unit, which is one of the block units constituting the hydrogenated block copolymer or modified hydrogenated block copolymer, is temporarily cleaved, and the resulting carbon radical structure causes carbon-carbon bond cleavage accompanied by β-hydrogen elimination, resulting in a decrease in molecular weight, and a low molecular weight modified hydrogenated block copolymer can be obtained from a high molecular weight hydrogenated block copolymer or modified hydrogenated block copolymer.
This operation may be carried out after the modification or simultaneously with the modification. That is, in order to reduce the molecular weight simultaneously with the modification, by adding a large amount of organic peroxide, the molecular weight can be reduced simultaneously with the modification.

The modified hydrogenated block copolymer preferably has a low dielectric constant. Specifically, the dielectric constant is preferably 3.0 or less, and more preferably 2.5 or less. If the dielectric constant is 3.0 or less, the signal transmission speed does not decrease.
The dielectric loss tangent of the modified hydrogenated block copolymer is preferably low. Specifically, it is preferably 0.003 or less, and more preferably 0.002 or less. If the dielectric loss tangent is 0.003 or less, the reliability of the electric signal is not reduced.

These low dielectric properties are important performance requirements for materials for electric and electronic components, such as laminates for electric and electronic circuits, and resin materials.
In recent years, communication frequencies have become higher in order to increase the amount and speed of information transmission. For example, since the transmission speed of an electric signal is inversely proportional to the square root of the (specific) dielectric constant of a material, a lower dielectric constant is preferable to improve the transmission speed of an electric signal. In addition, electric signals generate losses during transmission, and since the transmission loss is proportional to the dielectric tangent of a material, a lower dielectric tangent is preferable to reduce the transmission loss of an electric signal.
The use of a material with a low dielectric constant and low dielectric loss tangent means that there is little attenuation of information signals at high speeds, ensuring high reliability of communications.

<Solution or Slurry of Modified Hydrogenated Block Copolymer>
The modified hydrogenated block copolymer of the present invention can be dissolved or suspended in an organic solvent to form a solution or slurry.
The term "solution" used herein refers to a state in which the modified hydrogenated block copolymer is dissolved in an organic solvent, that is, a state in which the modified hydrogenated block copolymer is molecularly dispersed in the organic solvent.
The term "slurry" refers to a suspension in which particles of the modified hydrogenated block copolymer are mixed in an organic solvent.
Generally, polyolefins have poor solubility in organic solvents, and even if they do dissolve, they gel and are not suitable for coating. However, the modified hydrogenated block copolymer of the present invention exhibits unique properties in this respect.

The organic solvents in which the modified hydrogenated block copolymer of the present invention can be dissolved include aromatic solvents, aliphatic solvents, and alicyclic solvents.
Examples of aromatic solvents include benzene, toluene, xylene, ethylbenzene, chlorobenzene, and bromonaphthalene. Examples of aliphatic solvents include hexane, heptane, octane, nonane, and decane. Examples of alicyclic solvents include cyclopentane, cyclohexane, cycloheptane, and cyclodecane.
These may be used alone or in combination of two or more.
Among these, toluene and cyclohexane are preferred from the viewpoints of ease of handling and distillation.

In addition, organic solvents other than those mentioned above can be added to the extent that they do not impair the effects of the present invention. Examples of other organic solvents that can be used include ketones such as acetone, methyl ethyl ketone, cyclohexanone, acetophenone, and benzophenone; alcohols such as methanol, ethanol, isopropyl alcohol, and butanol; phenols such as phenol, cresol, and naphthol; ethers such as ethylene glycol monomethyl ether; and amides such as N,N-dimethylformamide and N,N-dimethylacetamide.

The concentration of the modified hydrogenated block copolymer in the above solution or slurry is preferably 1 to 30% by mass.
If the concentration of the modified hydrogenated block copolymer is equal to or higher than the lower limit, the solution viscosity is appropriate and suitable for coating operations, whereas if the concentration is equal to or lower than the upper limit, the solution viscosity is appropriate and gelation does not occur.
The concentration of the modified hydrogenated block copolymer in the above solution or slurry is more preferably 5 to 10% by mass.

<Other ingredients>
The solution or slurry of the present invention may contain components other than those listed above in order to further improve its functionality.
Such other components include thermosetting resins, photocurable resins, curing accelerators, ultraviolet inhibitors, antioxidants, coupling agents, plasticizers, fluxes, flame retardants, colorants, dispersants, emulsifiers, elasticity reducing agents, diluents, antifoaming agents, ion trapping agents, inorganic fillers, and organic fillers.

<Laminate of modified hydrogenated block copolymer>
The modified hydrogenated block copolymer of the present invention has good adhesive strength to substrates such as metals, glass and plastics, provides a non-sticky adhesive surface, and can form laminates with substrates such as metals, glass or plastics.
There is no particular restriction on the lamination method, and any known lamination method such as melt coextrusion molding, heat lamination processing, or insert injection molding can be used.

The above-mentioned melt coextrusion molding is a method of melt coextrusion molding the modified hydrogenated block copolymer of the present invention with one or more other thermoplastic resins, thereby producing a laminate containing the modified hydrogenated block copolymer.

Examples of the other thermoplastic resins include ethylene-α-olefin copolymers such as ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, and ethylene-(meth)acrylic acid ester copolymer; polyolefin resins such as polyethylene, polypropylene, and polybutene-1 resin; polyamide resins such as polyphenylene ether resins, nylon 6, and nylon 66; aromatic polyester resins such as aramid resins, polyethylene terephthalate, and polybutylene terephthalate; aliphatic polyester resins such as polylactic acid, polybutylene succinate, and polycaprolactone; polycarbonate resins; polyarylate resins; modified polyphenylene oxide resins; polysulfone resins; polyphenylene sulfide resins; polyethersulfone resins; polyether ketone resins; polyether ether ketone resins; polyimide resins; polyoxymethylene homopolymers, polyoxymethylene copolymers, and the like. Examples of suitable elastomers include ethylene-based resins; polymethyl methacrylate-based resins; silicon-containing soft polymers such as dimethylpolysiloxane, diphenylpolysiloxane, and dihydroxypolysiloxane; vinyl aromatic polymers such as polystyrene; ethylene-propylene copolymer rubber (EPM), ethylene-propylene-non-conjugated diene copolymer rubber (EPDM), ethylene-butene copolymer rubber (EBM), and ethylene-propylene-butene copolymer rubber; styrene-based elastomers such as styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, styrene-ethylene/butylene-styrene block copolymers, and styrene-ethylene/propylene-styrene block copolymers; polybutadiene; hydrogenated vinyl aromatic polymers, and other hydrogenated vinyl aromatic block copolymers including hydrogenated styrene/butadiene or styrene/isoprene block copolymers; and cycloolefin (co)polymers.
These may be used alone or in combination of two or more.

The above-mentioned thermal lamination process is a method of thermally laminating the modified hydrogenated block copolymer of the present invention onto a lamination substrate such as metal, paper, ceramics, thermoplastic resin, or thermosetting resin, thereby making it possible to produce a laminate containing the modified hydrogenated block copolymer.
The thermal lamination process is a method in which a film made of a modified hydrogenated block copolymer prepared in advance is brought into contact with the surface of a film or sheet to be a laminate substrate, and then the two are heated and fused together. Specifically, the method is a method in which a plurality of films or sheets are thermally fused together by passing them through a heated roll in a stacked state.

The modified hydrogenated block copolymer can be made into a film by a known method. Specifically, a T-die melt extrusion cast film molding method, an inflation film molding method, a calendar film molding method, or an extrusion lamination molding method can be used. In this case, it can be molded into a single layer film, or a multilayer film can be molded by a coextrusion molding method.
Among these, the T-die melt extrusion cast film molding method is preferred because it has excellent moldability and is easy to adjust.

In the T-die melt extrusion cast film molding method, the modified hydrogenated block copolymer is melt extruded at a temperature of 200 to 300°C through a T-type slit die having a slit width of about 0.1 to 2 mm attached to the tip of a single-screw or twin-screw extruder, and then the extruded film is brought into contact with the surface of a cooling roll set at 20 to 80°C to cool it, and then taken up to obtain a film.
If necessary, the film surface may be subjected to a corona treatment.

The obtained film is placed so as to overlap a laminate substrate such as metal, paper, ceramics, thermoplastic resin, or thermosetting resin, and is sandwiched between a heated metal roll and a rubber roll while applying pressure, thereby allowing lamination by thermal lamination.
When the film made of the modified hydrogenated block copolymer used has a multi-layer structure, it is necessary to arrange the layer made of the modified hydrogenated block copolymer so as to be in contact with the laminate substrate.

The temperature of the heating roll during the thermal lamination process is set as necessary, but must be equal to or higher than the glass transition point of the modified hydrogenated block copolymer. Although it depends on the processing speed of the thermal lamination, the thickness of the film and the laminate substrate, and the pressure for pressing, it is preferable to set the temperature 10 to 50° C. higher than the glass transition point of the modified hydrogenated block copolymer.
If the set temperature is 10° C. or higher than the glass transition point, sufficient adhesive strength can be obtained by the thermal lamination process, and if the set temperature is 50° C. or lower than the glass transition point, the film made of the modified hydrogenated block copolymer will not melt or stick to the roll.

The pressure during the thermal lamination is preferably 1 to 40 kg/m as the linear pressure between the rolls. If the pressure is equal to or higher than the lower limit, sufficient adhesive strength can be obtained by the thermal lamination. If the pressure is equal to or lower than the upper limit, no wrinkles are generated and a beautiful appearance can be obtained.
The processing speed during the thermal lamination is preferably 0.5 to 50 m/min in terms of the balance between adhesive strength and productivity. If the processing speed is equal to or higher than the lower limit, the productivity is sufficient and it is economically preferable. On the other hand, if the processing speed is equal to or lower than the upper limit, sufficient adhesive strength is obtained.

Alternatively, a laminate can be obtained by applying a solution or slurry of the modified hydrogenated block copolymer of the present invention to a substrate such as metal, glass, or plastic, and then removing the solvent.
The coating method may be by a bar coater, a blade coater, a die coater, a gravure roll coater, a spray coater, or by a brush.

After coating, it is also possible to evaporate the solvent from the coated surface. This is usually done by blowing hot air, but it is also possible to combine reduced pressure treatment with heating, or to simultaneously apply pressure.

Examples of substrates that are the coated materials from which the above laminates are obtained include metals and alloys such as copper, aluminum, iron, stainless steel, nickel, zinc, titanium, and tungsten; glasses such as glass plates, glass fiber mats, glass fiber cloths, and glass wool; and plastics such as polyethylene, polypropylene, polybutene, ethylene-α-olefin copolymers, propylene-α-olefin copolymers, ethylene-acrylic ester copolymers, ethylene-vinyl monomer copolymers, polyamides, and ethylene-vinyl acetate copolymers (EVOH).
These may be in the form of a plate, a film, or other shapes, may be made of a single material or may be composite, and may be single-layered or laminated.

Of these substrates, copper is preferred for electronic components such as circuit boards in terms of electrical conductivity and economy, iron and stainless steel are preferred for handrails and plywood in terms of economy and rigidity, aluminum is preferred for battery packaging and other applications in terms of light weight and processability, and polyamide and EVOH are preferred for food packaging in terms of gas barrier properties.

In the laminate obtained by the thermal lamination process, the layer containing the modified hydrogenated block copolymer preferably has a thickness of 5 to 500 μm.
If the thickness of the layer is 5 μm or more, the strength of the layer is sufficient, and as a result, the adhesive strength of the laminate is sufficient.
Furthermore, if the thickness of the above layer is 500 μm or less, heat transfer during thermal lamination is sufficient, and the rigidity of the layer containing the modified hydrogenated block copolymer is not high, resulting in a laminate having sufficient adhesive strength and not losing flexibility as a laminate.

In the laminate obtained by coating, the layer containing the modified hydrogenated block copolymer preferably has a thickness of 1 to 100 μm.
If the thickness of the layer is 1 μm or more, the adhesive strength of the coating film is not reduced.
Furthermore, if the thickness of the layer is 100 μm or less, the thickness can be easily controlled during coating, and there is no effect on productivity.

<Application>
The modified hydrogenated block copolymer of the present invention has the advantages of being transparent, heat resistant, excellent solubility in organic solvents, and excellent adhesion to substrates such as metals, glass, and plastics.
Furthermore, a solution containing the modified hydrogenated block copolymer of the present invention also has the effect of providing a laminate having excellent adhesion to substrates such as metals, glass, and plastics.
For this reason, it can be applied in various fields such as adhesives, paints, civil engineering and construction materials, and insulating materials for electric and electronic parts, and is particularly useful as insulating casting, laminating materials, sealing materials, etc. in the electric and electronic fields.

Examples of applications of the modified hydrogenated block copolymer of the present invention or a solution or slurry using the same include copper foil laminates, flexible printed circuit boards, multilayer printed wiring boards, capacitors and other laminates for electric and electronic circuits; adhesives such as film adhesives and liquid adhesives; semiconductor encapsulation materials, underfill materials, interchip fills for 3D-LSI, insulating sheets, prepregs, and heat dissipation substrates.

<Laminate containing conductive metal layer>
The modified hydrogenated block copolymer of the present invention and a solution or slurry using the same can also be suitably used as a laminate containing a conductive metal layer, such as the above-mentioned laminate for electric and electronic circuits.
This laminate containing a conductive metal layer is obtained by laminating a layer containing the modified hydrogenated block copolymer of the present invention and a conductive metal layer, and so long as it is a laminate of a layer containing the modified hydrogenated block copolymer of the present invention and a conductive metal layer, it includes laminates such as circuits having capacitors in addition to the above-mentioned electric/electronic circuits.
In addition, in the laminate containing the conductive metal layer, layers made of two or more kinds of modified hydrogenated block copolymers may be formed, and it is sufficient that the modified hydrogenated block copolymer of the present invention is used in at least one layer. Also, two or more kinds of conductive metal layers may be formed.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the following examples and comparative examples, various physical properties were measured by the following methods.

<Molecular weight>
・Apparatus: Tosoh Corporation GPC HLC-832GPC/HT
Detector: MIRAN 1A infrared spectrophotometer (measurement wavelength: 3.42 μm)
Column: Showa Denko K.K. AD806M/S, 3 columns (the columns were calibrated with Tosoh monodisperse polystyrene (A500, A2500, F1, F2, F4, F10, F20, F40, F288, each 0.5 mg/ml solution), and the elution volume and the logarithm of the molecular weight were approximated by a cubic equation.
・Measurement temperature: 135℃
・Concentration: 20mg/10mL
・Injection amount: 0.2ml
Solvent: o-dichlorobenzene Flow rate: 1.0 ml/min

<Polymer block ratio>
[Measurement by Carbon NMR]
Apparatus: Bruker "AVANCE 400 Spectrometer"
Solvent: o-dichlorobenzene- _h4 /p-dichlorobenzene- _d4 mixed solvent Concentration: 0.3 g/2.5 mL
・Measurement: ^13C -NMR
・Resonance frequency: 400MHz
Flip angle: 45 degrees Data acquisition time: 1.5 seconds Pulse repetition time: 15 seconds Number of integrations: 3600
・Measurement temperature: 100℃
・^1H irradiation: Complete decoupling

<Hydrogenation Level of Hydrogenated Vinyl Aromatic Polymer Block Unit, Hydrogenation Level of Hydrogenated Conjugated Diene Polymer Block Unit>
[Measurement by proton NMR]
Apparatus: Bruker "AVANCE 400 Spectrometer"
Solvent: Tetrachloroethane Concentration: 0.045 g/1.0 mL
・Measurement: ^1H -NMR
・Resonance frequency: 400MHz
Flip angle: 45 degrees Data acquisition time: 4 seconds Pulse repetition time: 10 seconds Number of integrations: 64
・Measurement temperature: 80℃
Hydrogenation level of hydrogenated aromatic vinyl polymer block unit: integral value reduction rate of 6.8 to 7.5 ppm Hydrogenation level of hydrogenated conjugated diene polymer block unit: integral value reduction rate of 5.7 to 6.4 ppm

<Modification ratio of modified hydrogenated block copolymer>
[Measurement by proton NMR]
Apparatus: BRUKER "AVANCE 400 Spectrometer"
Solvent: deuterated o-dichlorobenzene Concentration: 20 mg/0.62 mL
・Measurement: ^1H -NMR
・Resonance frequency: 400MHz
Flip angle: 45 degrees Data acquisition time: 4 seconds Pulse repetition time: 10 seconds Number of integrations: 64
・Measurement temperature: 120℃
Modification ratio of modified hydrogenated block copolymer: After the modified hydrogenated block copolymer is subjected to methyl esterification treatment, the signal at 3.42 to 3.94 ppm is counted as dimethyl maleate, and the ratio is calculated from 1/2 of the integral value.

<Transparency>
Using an SE-18D injection molding machine manufactured by Sumitomo Heavy Industries, Ltd., a flat plate of 2 mm x 40 mm x 80 mm was injection molded at a molding temperature of 220° C. and a mold temperature of 40° C. Using this plate, haze measurement was carried out in accordance with the measurement method described in JIS K7105 (1981).
The measured haze value was used to evaluate transparency. The evaluation results are shown in Table 1. The lower the haze value, the better the transparency.

<Heat resistance>
Three sheets of the above-obtained plates were stacked, and the Vicat softening temperature was measured according to the method described in JIS K7206 (1999). The measured Vicat softening temperature was used to evaluate heat resistance. The evaluation results are shown in the table. The higher the Vicat softening temperature, the higher the heat resistance.

<Dielectric properties (dielectric constant, dielectric tangent)>
A press sheet of 2 mm x 100 mm x 100 mm was prepared at a molding temperature of 240° C. This sheet was used as a test piece, and the dielectric constant (ε′) and dielectric loss tangent (tan δ) were measured using a vector network analyzer (KEYSIGHT PNA N5227A) at a measurement frequency of 50 GHz, a temperature of 25° C., and a humidity of 40%.

<Adhesiveness>
As the aluminum plate, a JIS H4000 A5052P aluminum plate of 1 mm x 70 mm x 150 mm was used.
As the stainless steel plate, a JIS G4305 SUS304 BA stainless steel plate of 0.5 mm x 70 mm x 150 mm was used.
The copper plate used was a JIS H3100 C1100P copper plate measuring 0.8 mm x 25 mm x 150 mm.
The polyamide plate used was Novamid 1020C manufactured by DSM, which was injection molded into a flat plate measuring 2 mm x 40 mm x 80 mm at a molding temperature of 240°C and a mold temperature of 40°C using an SE-18D injection molding machine manufactured by Sumitomo Heavy Industries, Ltd.
The EVOH plate was EVAL F101B manufactured by Kuraray Co., Ltd., and injection molded into a flat plate of 2 mm x 40 mm x 80 mm at a molding temperature of 220°C and a mold temperature of 40°C using an SE-18D injection molding machine manufactured by Sumitomo Heavy Industries, Ltd.

The surfaces of the metal plates and resin plates used were wiped with acetone, and then the solution was applied to a thickness of 50 μm using a wire bar coater. Hot air at 80° C. was then blown onto the plates to remove the solvent, and the plates were then subjected to reduced pressure treatment at 50° C. for 2 hours in a reduced pressure dryer.
Thereafter, 100 1 mm wide grids were cut into the coated surface using an NT cutter, and then Nichiban cloth adhesive tape LS No. 123 was attached and then peeled off, and the number of remaining grids out of the 100 was observed to evaluate adhesion.
The evaluation results are shown in Table 1. The more squares remaining, the better the adhesion.

<Ingredients>
[Hydrogenated block copolymer (a-1)]
Mitsubishi Chemical Corporation Zelas (registered trademark) MC930
MFR (230°C, 2.16 kg): 1 g/10 min; hydrogenated aromatic vinyl polymer block unit: hydrogenated polystyrene having a content of 65 mol% and a hydrogenation level of 99.5% or more; hydrogenated conjugated diene polymer block unit: hydrogenated polybutadiene having a content of 35 mol% and a hydrogenation level of 99.5% or more; block structure: pentablock structure, total hydrogenation level: 99.5% or more. The hydrogenated block copolymer (a-1) is a hydrogenated block copolymer that has not been modified with an unsaturated carboxylic acid and/or an unsaturated carboxylic anhydride.

[Organic peroxide]
Perhexa 25B manufactured by Nippon Oil & Fats Co., Ltd.
2,5-dimethyl-2,5-di(t-butylperoxy)hexane

Example 1
[Modified hydrogenated block copolymer (A-1)]
100 parts by mass of the hydrogenated block copolymer (a-1) were mixed with 1.3 parts by mass of maleic anhydride and 0.0065 parts by mass of an organic peroxide, and the mixture was thoroughly stirred.
Thereafter, the mixture was melt-kneaded using a twin-screw extruder (TEX25αIII, manufactured by Japan Steel Works, Ltd.) at a cylinder temperature of 280° C., a screw rotation speed of 400 rpm, and a discharge rate of 10 kg/h, and the extruded molten strand was water-cooled and cut to obtain a modified hydrogenated block copolymer (A-1).
The physical properties of the obtained A-1 are as follows and are also shown in Table 1.
MFR (230°C, 2.16 kg): 3 g/10 min. Hydrogenated aromatic vinyl polymer block unit: hydrogenated polystyrene with a content of 65 mol% and a hydrogenation level of 99.5% or more. Hydrogenated conjugated diene polymer block unit: hydrogenated polybutadiene with a content of 35 mol% and a hydrogenation level of 99.5% or more. Block structure: pentablock structure, total hydrogenation level: 99.5% or more. Maleic anhydride modification rate: 1.2 mass%.

5 g of A-1 and 100 ml (86.2 g) of toluene were placed in a 200 mL separable flask, heated to 60° C., and stirred for 1 hour. All of A-1 was dissolved, resulting in a colorless, transparent solution.
The above-mentioned evaluations were carried out using solutions A-1 and A-1. The evaluation results are shown in Table 1.

Example 2
[Modified hydrogenated block copolymer (A-2)]
100 parts by mass of the obtained A-1 was mixed with 1 part by mass of an organic peroxide and thoroughly stirred.
Thereafter, the mixture was melt-kneaded in the same manner as in Example 1 to obtain a modified hydrogenated block copolymer (A-2). The physical properties of the obtained A-2 are shown in Table 1.

A toluene solution was obtained in the same manner as in Example 1, except that A-2 was used instead of A-1. A-2 was completely dissolved, and a colorless, transparent solution was obtained.
The above-mentioned evaluations were carried out using solutions A-2 and A-2. The evaluation results are shown in Table 1.

<Comparative Example 1>
[Hydrogenated block copolymer (a-1)]
A toluene solution was obtained in the same manner as in Example 1, except that a-1 was used instead of A-1. All of a-1 was dissolved, resulting in a colorless, transparent solution.
The above-mentioned evaluations were carried out using solutions a-1 and a-1. The evaluation results are shown in Table 1.

<Comparative Example 2>
[Modified block copolymer (a-2)]
As the maleic anhydride modified product of the hydrogenated styrene-butadiene block copolymer, Tuftec M1943 manufactured by Asahi Kasei Corporation was used.
a-2 is a maleic anhydride modified block copolymer, but the aromatic vinyl polymer block units of the raw material block copolymer are not hydrogenated.
A toluene solution was obtained in the same manner as in Example 1, except that a-2 was used instead of A-1. All of a-2 was dissolved, resulting in a colorless, transparent solution.
The above-mentioned evaluations were carried out using solutions a-2 and a-2. The evaluation results are shown in Table 1.

<Comparative Example 3>
[Modified polyolefin (a-3)]
As the propylene-butene copolymer, Tafmer XM7070 manufactured by Mitsui Chemicals, Inc. was used, which was modified with maleic anhydride in the same manner as in Example 1 to obtain an acid-modified propylene-butene copolymer (a-3).
A toluene solution was obtained in the same manner as in Example 1, except that a-3 was used instead of A-1. All of a-3 was dissolved, resulting in a colorless, transparent solution.
The above evaluations were carried out using solutions a-3 and a-3. Since a-3 was inferior in transparency and heat resistance, the dielectric properties were not evaluated. The evaluation results are shown in Table 1.

<Comparative Example 4>
[Modified polyethylene (a-4)]
As the acid-modified polyethylene, Modic M704 manufactured by Mitsubishi Chemical Corporation was used.
An attempt was made to dissolve a-4 in toluene in the same manner as in Example 1, except that a-4 was used instead of A-1. However, the entire amount of a-4 did not dissolve, and it became a cloudy gel, which could not be used for coating. Therefore, it was not possible to evaluate the adhesiveness. In addition, since a-4 was inferior in transparency and heat resistance, the dielectric properties were not evaluated. The evaluation results are shown in Table 1.

<Comparative Example 5>
[Modified polypropylene (a-5)]
Modic P908 manufactured by Mitsubishi Chemical Corporation was used as the acid-modified polypropylene.
An attempt was made to dissolve a-5 in toluene in the same manner as in Example 1, except that a-5 was used instead of A-1, but a-5 did not dissolve and could not be used for coating. Therefore, it was not possible to evaluate the adhesiveness. In addition, since a-5 has poor transparency, the dielectric properties were not evaluated. The evaluation results are shown in Table 1.

<Comparative Example 6>
[Block copolymer (a-6)]
As the hydrogenated styrene-butadiene block copolymer, Kraton G1652 manufactured by Kraton Polymers was used.
a-6 is a block copolymer in which the aromatic vinyl polymer block units are neither hydrogenated nor acid-modified.
The test piece a-6 was designed to show the level of heat resistance and dielectric properties of the conventional product, and only the heat resistance and dielectric properties were evaluated. The evaluation results are shown in Table 1.

Example 3
A three-layer film was formed at 260° C. and a speed of 5 m/min in a Labtech Engineering multilayer film forming machine using a-1 50 μm for the surface layer, a-1 10 μm for the intermediate layer, and A-1 20 μm for the seal layer.
Using a laminator manufactured by Tester Sangyo Co., Ltd., a film having a nylon/aluminum foil configuration and the three-layer film obtained above were used, and heat lamination was performed at a roll temperature of 200° C., a speed of 0.75 m/min, and a nip pressure of 0.3 MPa (linear pressure of 1.5 kg/m) by setting the seal layer of the three-layer film to be in contact with the aluminum surface.
The adhesive strength to aluminum was measured by a 90 degree peel test using the method described below. The results are shown in Table 2.

[90 degree peel test]
The 90-degree peel test is performed using a normal tensile tester and a jig for a 90-degree peel test. The strip test piece is fixed horizontally using the jig, and the end is peeled off slightly in advance. The peeled off part is gripped by the upper grip of the tensile tester and pulled upward, so that the strip test piece can be peeled off at an angle of 90 degrees to the direction of the strip test piece.
Since the peel point moves horizontally as the peel progresses, the jig holding the rectangular test piece is slid horizontally to ensure that the peel point is always located directly below the upper gripping part.
The tensile speed was 300 mm/min, and the measurement environment was a temperature of 23° C. and a humidity of 40% RH.

<Comparative Example 7>
Except for using a-1 as the sealing layer, the aluminum adhesive strength was measured in the same manner as in Example 3. The results are shown in Table 2.

From Table 1, it was found that the modified hydrogenated block copolymers of the present invention (Examples 1 and 2) have good transparency and heat resistance, as well as excellent dielectric properties and good adhesion to various substrates.
In contrast, it was found that the hydrogenated block copolymer before modification (Comparative Example 1) had good transparency and heat resistance, and was excellent in dielectric properties, but had insufficient adhesion to the substrate.
It was found that the modified block copolymer in which the aromatic vinyl polymer block units were not hydrogenated (Comparative Example 2) was inferior in transparency and heat resistance, and although it had excellent dielectric properties, it had almost no adhesion to the substrate.

It was found that the modified polyolefin (Comparative Example 3) was inferior in transparency and heat resistance, and had insufficient adhesion to the substrate.
The modified polyethylene (Comparative Example 4) and the modified polypropylene (Comparative Example 5) were not dissolved in the solvent, and therefore the adhesiveness by coating could not be evaluated.
The block copolymer (Comparative Example 6) represents the prior art. Comparison with Comparative Example 6 shows that the modified hydrogenated block copolymer of the present invention has good heat resistance and dielectric properties equal to or better than those of the prior art.

From Table 2, it was found that the laminate using the modified hydrogenated block copolymer of the present invention (Example 3) exhibited good adhesion to the aluminum foil when thermally laminated to the aluminum foil.
In contrast, it was found that the laminate using the unmodified hydrogenated block copolymer (Comparative Example 7) had almost no adhesion to the aluminum foil even when thermally laminated to the aluminum foil.

Claims (13)

A modified hydrogenated block copolymer, which is a hydrogenated block copolymer modified with an unsaturated carboxylic acid and/or an unsaturated carboxylic acid anhydride,
the hydrogenated block copolymer is a hydrogenated product of a copolymer including a polymer block composed of an aromatic vinyl monomer unit and a polymer block composed of a conjugated diene monomer unit,
the hydrogenated product of the polymer block composed of the aromatic vinyl monomer unit is a hydrogenated aromatic vinyl polymer block unit having a hydrogenation level of 90% or more, and the hydrogenated product of the polymer block composed of the conjugated diene monomer unit is a hydrogenated conjugated diene polymer block unit having a hydrogenation level of 95% or more,
the content of the hydrogenated aromatic vinyl polymer block unit is 50 to 99 mol % based on the hydrogenated block copolymer;
A modified hydrogenated block copolymer for use in electric and electronic parts , having a weight average molecular weight (Mw) of 5,000 to 80,000 . The modified hydrogenated block copolymer for electric and electronic parts according to claim 1, wherein the hydrogenated block copolymer has at least two of the hydrogenated aromatic vinyl polymer block units and at least one of the hydrogenated conjugated diene polymer block units. The modified hydrogenated block copolymer for electric/electronic parts according to claim 1 or 2, wherein the modification rate with the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride is 0.1 to 2 mass%. The modified hydrogenated block copolymer for electric/electronic parts according to any one of claims 1 to 3, wherein the unsaturated carboxylic acid and/or unsaturated carboxylic anhydride is maleic anhydride. A modified hydrogenated block copolymer solution for electric/electronic components or a modified hydrogenated block copolymer slurry for electric/electronic components, the modified hydrogenated block copolymer for electric/electronic components according to any one of claims 1 to 4 being dissolved or suspended in an organic solvent at a concentration of 1 to 30 mass %. A laminate containing a modified hydrogenated block copolymer for electric/electronic parts, comprising the modified hydrogenated block copolymer for electric/electronic parts according to any one of claims 1 to 4 laminated on a substrate. 7. The laminate containing the modified hydrogenated block copolymer for electric/electronic parts according to claim 6 , which is obtained by melt co-extrusion molding the modified hydrogenated block copolymer for electric/electronic parts with one or more other thermoplastic resins. 7. The laminate containing the modified hydrogenated block copolymer for electric and electronic parts according to claim 6 , wherein the modified hydrogenated block copolymer for electric and electronic parts is thermally laminated onto a metal, paper, ceramics, thermoplastic resin or thermosetting resin. 9. The laminate containing the modified hydrogenated block copolymer for electric and electronic parts according to claim 8 , wherein the layer containing the modified hydrogenated block copolymer for electric and electronic parts has a thickness of 5 to 500 μm. A method for producing the modified hydrogenated block copolymer for electric/electronic parts according to any one of claims 1 to 4 , comprising the steps of:
The hydrogenated block copolymer is graft-modified by any one of melt kneading, reaction in solution, and solid-phase grafting. A method for producing the modified hydrogenated block copolymer for electric/electronic parts according to any one of claims 1 to 4 , comprising the steps of:
The hydrogenated block copolymer is graft-modified with an unsaturated carboxylic acid and/or an unsaturated carboxylic acid anhydride to produce a modified hydrogenated block copolymer for use in electric/electronic parts. A method for producing a modified hydrogenated block copolymer-containing laminate for use in electric and electronic components, comprising applying the modified hydrogenated block copolymer solution or modified hydrogenated block copolymer slurry according to claim 5 to a substrate, and then removing the solvent to obtain a laminate. The method for producing a laminate containing a modified hydrogenated block copolymer for electric and electronic parts according to claim 12 , wherein the layer containing the modified hydrogenated block copolymer for electric and electronic parts has a thickness of 1 to 100 μm.