JP4767673B2 - Hydrogenated styrene elastomer laminate for diene rubber bonding - Google Patents

Description

  The present invention relates to a hydrogenated styrene-based elastomer laminate excellent in adhesiveness with a diene rubber.

  In recent years, as the quality requirements for polymer materials have increased, multiple properties (for example, tensile strength, tensile elasticity, hardness, abrasion resistance, heat resistance, cold resistance, oil resistance, chemical resistance, weather resistance) A material having molding processability is expected. For example, a material having characteristics of rubber and characteristics different from the characteristics of the rubber (for example, high elasticity, which is a characteristic of resin) is required. Therefore, the resin molded member and the rubber molded member may be joined and integrated to be used as a composite having resin and rubber characteristics.

  A block copolymer having a polymer block composed of an aromatic vinyl compound and a polymer block composed of a hydrogenated (hereinafter sometimes referred to as “hydrogenated”) conjugated diene compound is a hydrogenated styrene elastomer. Generally known as In general, it has better weather resistance than diene rubber, and since it does not have a chemical cross-linking structure, it can be molded by various molding methods and has different characteristics from so-called general rubber. It has been known.

  However, when a hydrogenated styrenic elastomer and rubber, such as a diene rubber, are used as a composite, the adhesiveness between the hydrogenated styrenic thermoplastic elastomer and the diene rubber is poor and practically sufficient adhesive strength. It is hard to say that it has.

  Examples of the improved adhesive properties include an unvulcanized rubber composition, a semi-vulcanized rubber member, and a vulcanized rubber member through an unvulcanized rubber layer containing a vulcanizing agent such as a radical generator. A method of adhering a rubber element selected from the above and a resin element selected from an unmolded resin composition, a semi-molded resin member, and a molded resin member has been proposed (for example, see Patent Document 1). As a result of the additional test of the invention by the inventors, the adhesiveness is still insufficient, and it is difficult to say that the adhesive strength is at a level with no practical problem.

JP 2004-42486 A

  An object of the present invention is to provide a hydrogenated styrene-based elastomer laminate excellent in adhesiveness with a diene rubber.

  As a result of intensive studies, the present inventors have found that a hydrogenated styrene-based elastomer laminate satisfying specific requirements is excellent in adhesiveness with a diene rubber, and have completed the present invention.

That is, the present invention
It has one or more polymer blocks (i) composed of conjugated diene compound units and two or more polymer blocks (ii) composed of vinyl aromatic compound units, and the carbon-carbon defect contained in the polymer block (i). A hydrogenated styrenic elastomer layer comprising a block copolymer (A) in which 90 mol% or more of saturated double bonds are hydrogenated;
An adhesive layer comprising a conjugated diene copolymer selected from a block copolymer (B) or a graft copolymer (C) having a conjugated diene polymer in at least a part of the main chain;
A hydrogenated styrene-based elastomer laminate for adhering a diene rubber ,
The block copolymer (B) has one or more polymer blocks (iii) composed of conjugated diene compound units and one or more polymer blocks (iv) composed of vinyl aromatic compound units, or
The graft copolymer (C) is one or more diene rubbers selected from natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, styrene-isoprene rubber, styrene-butadiene-isoprene rubber, and nitrile-butadiene rubber. The present invention relates to a hydrogenated styrene-based elastomer laminate for adhesion to a diene rubber, which is a (meth) acrylic acid ester-grafted diene rubber obtained by graft polymerization of a (meth) acrylic acid ester to the main chain .

  ADVANTAGE OF THE INVENTION According to this invention, the hydrogenated styrene-type elastomer laminated body excellent in adhesiveness with diene-type rubber is provided.

  The hydrogenated styrene elastomer laminate for diene rubber adhesion of the present invention comprises a block copolymer having a hydrogenated styrene elastomer layer comprising a block copolymer (A) and a conjugated diene polymer in at least a part of the main chain. It is a laminate having an adhesive layer made of a conjugated diene copolymer selected from a polymer (B) or a graft copolymer (C).

  In the present invention, the hydrogenated styrene elastomer layer has at least one polymer block (i) composed of a conjugated diene compound and at least two polymer blocks (ii) composed of a vinyl aromatic compound, It is comprised with the block copolymer (A) in which 90 mol% or more of the carbon-carbon unsaturated double bond contained in a block (i) is hydrogenated. The block chain structure of the block copolymer (A) is not particularly limited as long as the above conditions are satisfied. For example, (ii)-(i)-(ii) type triblock chain, (ii)-(i) -(Ii)-(i) type tetrablock linkage, (ii)-(i)-(ii)-(i)-(ii) type and (i)-(ii)-(i)-(ii) -(I) type pentablock type chain. Among these, the (ii)-(i)-(ii) type triblock chain is preferable from the viewpoint of ease of production and mechanical properties of the hydrogenated styrene elastomer laminate.

  In the block copolymer (A), examples of the conjugated diene compound used for forming the polymer block (i) include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 3,4 -Dimethyl-1,3-pentadiene, 1,3-cyclohexadiene and the like. Of these, 1,3-butadiene and isoprene are preferred from the viewpoints of availability and industrial economy. These may be used alone or in combination of two or more. Moreover, as long as the effect of this invention is not impaired, vinyl aromatic compounds, such as styrene, 4-methylstyrene, (alpha) -methylstyrene, may be copolymerized, for example.

  Examples of the vinyl aromatic compound used for forming the polymer block (ii) in the block copolymer (A) include styrene, 4-methylstyrene, 4-t-butylstyrene, 2-methylstyrene, and 3-methyl. Styrene compounds which may have a substituent in the aromatic ring such as styrene, 4-methoxystyrene, 4-t-butoxystyrene, vinylnaphthalene, vinylanthracene, α-methylstyrene, α-ethylstyrene, 1,1 Examples include α-substituted styrene compounds such as diphenylethylene, and styrene compounds in which the α-position and aromatic ring have a substituent such as 4, α-dimethylstyrene. Of these, styrene, 4-methylstyrene, and α-methylstyrene are preferable from the viewpoint of industrial economy and ease of polymerization, and α-methylstyrene is the high temperature of the resulting block copolymer (A). It is more preferable from the viewpoint of mechanical physical properties. These may be used alone or in combination of two or more.

  In the block copolymer (A), the mass fraction of the polymer block (ii) is not particularly limited, but from the viewpoint of performance as a thermoplastic elastomer, it is less than 60% by mass, and further less than 50% by mass. Is preferred. When the mass fraction of the polymer block (ii) exceeds 60% by mass, the resin properties become strong and the performance as an elastomer is inferior.

  Although there is no restriction | limiting in particular in the molecular weight of a block copolymer (A), Preferably it is 10,000-2,000,000, More preferably, it is the range of 30,000-1,000,000. When the molecular weight is 10,000 or less, the mechanical properties of the hydrogenated styrene elastomer laminate are unsatisfactory. On the other hand, when the molecular weight is 2,000,000 or more, the moldability is inferior. In addition, the molecular weight said here refers to the number average molecular weight (Mn) measured by gel permeation chromatography.

The conjugated diene copolymer constituting the adhesive layer is composed of a block copolymer (B) having a conjugated diene polymer block in a part of the polymer main chain and substantially all of the polymer main chain conjugated. Either or both selected from the graft copolymer (C) which is a diene polymer.
If the block copolymer (B) having a conjugated diene polymer block in a part of the main chain is a block copolymer having a polymer block (iii) composed of a conjugated diene compound unit, other The polymer block is not particularly limited, but from the viewpoint of adhesion between the hydrogenated styrene-based elastomer laminate of the present invention and the diene rubber, the other polymer blocks are vinyl aromatic compound units or (meth) acrylic. It is preferably a polymer block (iv) composed of an acid ester unit, and more preferably a vinyl aromatic compound unit from the viewpoint of ease of production.

  Examples of the conjugated diene compound unit constituting the polymer block (iii) include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 3,4-dimethyl-1,3-pentadiene, Examples include units consisting of 1,3-cyclohexadiene and the like. Among these, from the viewpoint of easy availability and industrial economy, a unit consisting of 1,3-butadiene and isoprene is preferable. These may be used alone or in combination of two or more. Moreover, as long as the effect of this invention is not impaired, vinyl aromatic compounds, such as styrene, 4-methylstyrene, (alpha) -methylstyrene, may be copolymerized, for example.

  A part of the carbon-carbon unsaturated double bond contained in the polymer block (iii) may be hydrogenated for the purpose of improving the weather resistance and the like, but the hydrogenation rate is 20 mol% or less. It is preferable from the viewpoint of adhesiveness of the hydrogenated styrene elastomer laminate to the diene rubber.

Examples of vinyl aromatic compound units that can constitute the polymer block (iv) include styrene, 4-methylstyrene, 4-t-butylstyrene, 2-methylstyrene, 3-methylstyrene, and 4-methoxystyrene. , A styrene compound optionally having a substituent on an aromatic ring such as 4-t-butoxystyrene, vinylnaphthalene, and vinylanthracene, α such as α-methylstyrene, α-ethylstyrene, and 1,1-diphenylethylene -Substituted styrene compounds, units composed of styrene compounds such as 4, α-dimethylstyrene and the like in which the α-position and aromatic ring have substituents.
As the (meth) acrylic acid ester unit that can constitute the polymer block (iv), methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, (meth) acrylic acid-n (Meth) acrylic acid alkyl esters such as butyl, (meth) acrylic acid-s-butyl, (meth) acrylic acid-t-butyl, (meth) acrylic acid 2-ethylhexyl, (meth) acrylic acid dodecyl, And a unit composed of (meth) acrylic acid esters such as glycidyl acrylate and hydroxyethyl (meth) acrylate.
Among these, from the viewpoint of adhesion to the diene rubber of the hydrogenated styrene-based elastomer laminate, a unit composed of styrene, 4-methylstyrene, α-methylstyrene, and methyl methacrylate is preferable, and polymerization is easy. From the viewpoint of properties, a unit composed of styrene, 4-methylstyrene, and α-methylstyrene is more preferable. These may be used alone or in combination of two or more.

  The block chain of the preferable block copolymer (B) is not particularly limited as long as it has one or more polymer blocks (iii) and one or more polymer blocks (iv). iii)-(iv) diblock copolymer, (iii)-(iv)-(iii), (iv)-(iii)-(iv) triblock copolymer, (iii)-(iv) The tetrablock copolymer of-(iii)-(iv) etc. are mentioned. Among these, from the viewpoint of ease of production, the diblock copolymer (iii)-(iv) and the triblock copolymer (iv)-(iii)-(iv) are preferable, and the hydrogenated styrenic elastomer A triblock copolymer of laminate (iv)-(iii)-(iv) is more preferred.

  In the block copolymer (B), the mass fraction of the polymer block (iii) in the block copolymer is not particularly limited, but is preferably 30 to 95% by mass, more preferably 50 to 90% by mass. is there. When the mass fraction of the polymer block (iii) is within this range, the adhesion between the hydrogenated styrene elastomer laminate and the diene rubber is improved.

  Although there is no restriction | limiting in particular in the molecular weight of the said block copolymer (B), Preferably it is 5,000-1,000,000, More preferably, it is 10,000-500,000. When the molecular weight is 5,000 or less, the adhesive force between the hydrogenated styrene elastomer laminate and the diene rubber is undesirably lowered, and when the molecular weight is 1,000,000 or more, the handling property during molding is lowered. Therefore, it is not preferable. In addition, the molecular weight said here refers to the number average molecular weight (Mn) measured by gel permeation chromatography.

  The graft copolymer (C) in which substantially all of the polymer main chain is a conjugated diene polymer is a polymer chain having a conjugated diene polymer as a main component as a trunk and other branches as branches. It refers to a graft copolymer having a polymer chain composed of components.

  In the above graft copolymer (C), the conjugated diene polymer chain includes natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, styrene-isoprene rubber, styrene-butadiene-isoprene rubber, and nitrile-butadiene rubber. A diene rubber selected from can be used. Of these, natural rubber, isoprene rubber, butadiene rubber, and styrene-butadiene rubber are preferred from the viewpoints of availability and industrial economy, and natural rubber and styrene-butadiene rubber are more preferred.

  In the above-mentioned graft copolymer (C), there is no particular limitation on the component constituting the polymer chain composed of other components, for example, vinyl aromatic compounds such as styrene, p-methylstyrene, α-methylstyrene, Examples include units composed of vinyl compounds such as (meth) acrylic acid esters such as methyl methacrylate, ethyl methacrylate, glycidyl methacrylate, methyl acrylate and butyl acrylate, and vinyl ester compounds such as vinyl acetate. Among these, from the viewpoint of adhesion between the hydrogenated styrene-based elastomer laminate and the diene rubber, a unit composed of a vinyl aromatic compound or a (meth) acrylic acid ester is preferable, and from the viewpoint of availability, a methyl methacrylate unit is preferable. More preferred. These may be used alone or in combination of two or more.

  There is no particular limitation on the mass fraction of the polymer chain composed of other components in the graft copolymer, but from the viewpoint of the adhesive strength between the hydrogenated styrene elastomer laminate and the diene rubber, it is more preferably 3% by mass or more. Is 10% by mass or more. When the mass fraction of the polymer chain composed of other components is less than 3% by mass, the adhesive force between the hydrogenated styrene elastomer laminate and the diene rubber is unfavorable.

  There are no particular restrictions on the method for producing the block copolymer (A) constituting the hydrogenated styrene elastomer layer and the block copolymer (B) capable of constituting the adhesive layer in the present invention. It can be manufactured using legal methods. In this case, it can be obtained by sequentially polymerizing a vinyl aromatic compound and a conjugated diene compound in an inert organic solvent such as n-hexane, cyclohexane, benzene, and toluene in the presence of an anionic polymerization initiator such as an alkyl lithium compound. it can.

When producing block copolymers by living anionic polymerization, there is no functional group (hydroxyl group, carbonyl group, etc.) that reacts with anion species in the molecule in order to make the reaction proceed smoothly. A polar compound having an atom may be used in the presence of an inert organic solvent. As a polar compound in that case, an appropriate compound can be selected according to the method employed in ordinary living anion polymerization, and diethyl ether, monoglyme, diglyme, N, N, N ′, N′-tetra Mention may be made of methylethylenediamine, dimethoxyethane, tetrahydrofuran and the like. These may be used alone or in combination of two or more.

  Moreover, when manufacturing a block copolymer by living anion polymerization, you may use a polyfunctional coupling agent as needed. As the polyfunctional coupling agent, an appropriate one can be selected according to the technique employed in ordinary living anionic polymerization, and phenyl benzoate, methyl benzoate, ethyl benzoate, ethyl acetate, methyl acetate , Methyl pivalate, phenyl pivalate, ethyl pivalate, α, α'-dichloro-o-xylene, α, α'-dichloro-m-xylene, α, α'-dichloro-p-xylene, bis (chloromethyl ) Ether, dibromomethane, diiodomethane, dimethyl phthalate, dichlorodimethylsilane, dichlorodiphenylsilane, trichloromethylsilane, tetrachlorosilane, divinylbenzene and the like.

  Moreover, when manufacturing a block copolymer by living anion polymerization, you may introduce | transduce a functional group to the block copolymer terminal using a functional capping agent as needed. As a functional capping agent, an appropriate one can be selected according to the technique employed in ordinary living anion polymerization. A capping agent capable of introducing a hydroxyl group (alkylene oxides such as ethylene oxide) or a carboxyl group is introduced. Capping agents (such as carbon dioxide), capping agents capable of introducing amino groups (imine compounds such as ethyleneimine), capping agents capable of introducing mercapto groups (carbon disulfide, sulfur atoms, and alkylene sulfides such as ethylene sulfide) And the like.

  The method for hydrogenating carbon-carbon double bonds derived from the conjugated diene compound of the block copolymer is not particularly limited. For example, the block copolymer is reacted with hydrogen in the presence of a Ni / Al Ziegler catalyst. And the like.

  The production method of the graft copolymer (C) that can be used in the present invention is not particularly limited. For example, a diene rubber and a polymerizable monomer, a radical generator and, if necessary, a solvent, a dispersion medium, etc. For example, a rubber latex obtained by graft polymerization of methyl methacrylate using a natural rubber latex as a base material is generally known. These are commercially available, for example, as REGI-TEX MG series from RE-TEX, and these may be used.

  In addition to the above components, sulfur is added to the adhesive layer constituting the hydrogenated styrene elastomer laminate of the present invention and / or the hydrogenated styrene elastomer layer for the purpose of improving the adhesion to the diene rubber. Or a vulcanizing agent such as an organic peroxide. Examples of organic peroxides include di-t-butyl peroxide, dicumyl peroxide, di-t-hexyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, t-butylcumyl peroxide, di-t-butyl oxide, p-menthane hydroperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, diisopropylbenzene hydroperoxide, 1 1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide and the like. These may be used alone or in combination of two or more. The amount of the organic peroxide is not particularly limited as long as it does not substantially impair the effects of the present invention. Generally, the amount of the organic peroxide is 0.00 with respect to 100 parts by mass of the adhesive layer and / or the hydrogenated styrene elastomer layer. It is preferable that it is 01-10 mass parts.

  In the adhesive layer and / or hydrogenated styrene elastomer layer constituting the hydrogenated styrene elastomer laminate of the present invention, other thermoplastic resins, softeners, inorganic fillers are used as in general styrene elastomers. Agents, dyes and pigments, additives and the like may be mixed.

  The thermoplastic resin that can be used in the hydrogenated styrene elastomer laminate of the present invention is not particularly limited as long as it does not substantially impair the effects of the present invention. For example, polyphenylene ether resin, polyamide 6, polyamide 6,6, polyamide 6/10, polyamide 11, polyamide 12 and other polyamide resins, polyethylene terephthalate, polybutylene terephthalate and other polyester resins, polyoxymethylene homopolymer, polyoxymethylene copolymer and other polyoxymethylene resins, Styrene homopolymer, α-methylstyrene homopolymer, styrene / α-methylstyrene copolymer, styrene resin such as acrylonitrile / styrene resin, acrylonitrile / butadiene / styrene resin, polycarbonate resin, polymethylmeta (Meth) acrylate resins such as acrylate, styrene-methyl methacrylate copolymer, natural rubber, synthetic isoprene rubber, chloroprene rubber, acrylic rubber, butyl rubber, acrylonitrile butadiene rubber, epichlorohydrin rubber, silicone rubber, fluorine rubber, urethane Examples thereof include rubber, polyurethane-based elastomer, polyamide-based elastomer, polyester-based elastomer, vinyl chloride resin, soft vinyl chloride resin, polyolefin resin such as polyethylene, polypropylene, and polybutene-1. These may be used alone or in combination of two or more.

Examples of the softening agent that can be used in the styrene elastomer laminate of the present invention include hydrocarbon oils such as paraffin oil, naphthene oil, and aroma oil.
Examples of the inorganic filler and dye / pigment that can be used in the styrene elastomer laminate of the present invention include carbon black, silica, calcium carbonate, talc, clay, and titanium oxide.
Additives that can be used in the styrene elastomer laminate of the present invention include lubricants, light stabilizers, flame retardants, antistatic agents, silicone oil, antiblocking agents, ultraviolet absorbers, antioxidants, mold release agents, A foaming agent, a fragrance | flavor, etc. are mentioned.

  The method for producing the hydrogenated styrene-based elastomer laminate of the present invention is not particularly limited. However, a method of laminating the adhesive layer and the hydrogenated styrene-based elastomer layer, a method of laminating, a method of heat laminating, and a multilayer Adopting a batch production method such as extrusion molding and two-color molding, a method of applying a latex of an adhesive layer component dissolved and dispersed in a solvent or dispersion medium, a method of performing a heat treatment after performing these operations, etc. Can do.

Although there is no restriction | limiting in particular about the tensile breaking strength of the hydrogenated styrene-type elastomer laminated body of this invention, It is preferable that it is 15 Mpa or more from a viewpoint of practical strength. When the tensile strength at break is 15 MPa or less, the strength as an elastomer is inferior, which is not preferable.
Moreover, there is no restriction | limiting in particular about the tensile breaking elongation of the hydrogenated styrene-type elastomer laminated body of this invention, However, From a viewpoint of the function as an elastomer, it is preferable that it is 100% or more, More preferably, it is 200% or more. When the tensile elongation at break is 100% or less, it is not preferable because the performance as an elastomer is inferior.

  The adhesive force of the hydrogenated styrene-based elastomer laminate of the present invention to the diene rubber can be determined, for example, by measuring the peel strength according to JIS K6256. From the viewpoint that the composite of the hydrogenated styrene elastomer laminate and the vulcanized diene rubber has a sufficient practical strength, the peel strength between the hydrogenated styrene elastomer laminate and the vulcanized diene rubber is preferably 2.5 N / mm or more, more preferably 3 N / mm or more. When the peel strength is less than 2.5 N / mm, the practical strength of the composite is inferior. The above peel strength includes, in addition to interfacial peeling of the adhesive layer, material destruction of one of the layers and cohesive failure of the adhesive layer.

  The above-mentioned diene rubber is one or more diene rubbers selected from natural rubber, synthetic isoprene rubber, butadiene rubber, styrene butadiene rubber, styrene isoprene rubber, styrene-butadiene-isoprene rubber and nitrile butadiene rubber and a vulcanizing agent. The diene type rubber composition which contains at least. In addition to the diene rubber and vulcanizing agent described above, the diene rubber composition includes an inorganic filler such as carbon black and silica, a softening agent such as naphthenic oil, a vulcanizing agent, a vulcanization accelerator, and a vulcanizing aid. Further, a vulcanization acceleration aid, stearic acid, zinc white, silane coupling agent and the like may be appropriately blended depending on the purpose.

  As a method for bonding the hydrogenated styrene-based elastomer laminate and the diene rubber of the present invention, for example, an unvulcanized diene rubber composition is used, and the adhesive layer surface of the laminate is unvulcanized or contains a vulcanizing agent. Arrangement so as to be in contact with semi-vulcanized diene rubber composition, vulcanization adhesion method, using vulcanized diene rubber composition, adhesive layer surface containing vulcanizing agent of laminate is vulcanized diene system For example, a method of placing the rubber composition in contact with rubber and vulcanizing and bonding the rubber may be used. Among these, it is preferable to employ a method of performing vulcanization adhesion using an unvulcanized diene rubber composition containing a vulcanizing agent because of ease of process.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention concretely, this invention is not limited by it at all. In addition, measuring instruments and measuring methods and materials used in the following examples and comparative examples are shown.

(1) Analysis equipment of the molecular structure of the block copolymer by nuclear magnetic resonance spectra ⁽¹ H-NMR spectrum): manufactured by JEOL Ltd. nuclear magnetic resonance apparatus (JNM-LA)
Solvent: Deuterated chloroform (2) Measurement of number average molecular weight (Mn) and molecular weight distribution (Mw / Mn) by gel permeation chromatography (GPC) Equipment: Gel permeation chromatograph (HLC-8020) manufactured by Tosoh Corporation
Column: Tosoh TSKgel GMHXL, G4000HXL and G5000HXL connected in series Eluent: Tetrahydrofuran, flow rate 1.0 ml / min Column temperature: 40 ° C.
Calibration curve: Created using standard polystyrene Detection method: Differential refractive index (RI)
(3) Measurement of tensile breaking strength and tensile breaking elongation A dumbbell-shaped No. 3 test piece was punched from a sheet of 2 mm thickness produced by compression molding, and a universal material testing machine (Instron) in accordance with JIS K6251. Using “TM-MS-134” manufactured by Japan Co., Ltd.), the measurement was performed under the condition of 500 mm / min.
(4) Adhesion test with diene rubber An unvulcanized rubber sheet having a thickness of 2 mm prepared by blending various materials in the proportions shown in Table 1, and a 2 mm thickness of the thermoplastic elastomer composition of the present invention. The sheets were stacked and vulcanized and bonded at 170 ° C. for 15 minutes. The bonded sample was cut into a 25 mm width strip, and in accordance with JIS K6256, using a universal material testing machine (“TM-MS-134” manufactured by Instron Japan) under the conditions of 90 ° and 500 mm / min. The peel strength was measured. Moreover, the peeling state of the test piece after a test was observed, and it classified as follows.
A: Material failure of vulcanized diene rubber B: Material failure of hydrogenated styrene elastomer layer C: Cohesive failure of adhesive layer D: Interfacial debonding of hydrogenated styrene elastomer layer and vulcanized diene rubber

<< Reference Production Example 1 >> Production of Hydrogenated Styrene Elastomer (A-1) (1) In an autoclave sufficiently purged with nitrogen, 152 g of α-methylstyrene, 221 g of cyclohexane, 38.5 g of hexane, and 9.6 g of tetrahydrofuran Was introduced.
(2) Subsequently, 10 mL of sec-butyllithium cyclohexane solution (10 mmol as sec-butyllithium) was added, and a polymerization reaction was performed at -10 ° C for 3 hours. Polymerization start 5
When Mn and Mw / Mn of poly α-methylstyrene (corresponding to polymer block ( ii )) after time were measured by GPC, Mn = 10500, Mw / Mn = 1.05, and α-methylstyrene The polymerization conversion was 90%.
(3) Next, after adding 10 g of 1,3-butadiene and stirring for 30 minutes, the temperature was raised to 10 ° C. and 109 g of cyclohexane was added to dilute the polymerization solution. Subsequently, 317 g of the polymerization solution was extracted, and 524 g of cyclohexane was further added.
(4) Next, 128 g of 1,3-butadiene was added and polymerization was carried out at 50 ° C. for 2 hours. When Mn and Mw / Mn of the polymer obtained by sampling at this time were measured by GPC, Mn = 59700, Mw / Mn = 1.05, 1,4-bond of polybutadiene part determined from ¹ H-NMR measurement The amount was 60 mol%.
(5) Subsequently, 10 mL of a cyclohexane solution of phenyl benzoate (2.64 mmol as phenyl benzoate) was slowly added and stirred at 50 ° C. for 1 hour. After stirring, a small amount of degassed methanol was added to complete the polymerization. The number average molecular weight of the obtained polymer
When measured by C, Mn = 119600 and Mw / Mn = 1.06. ¹ H-
The mass fraction of the α-methylstyrene polymer block determined from NMR measurement was 30% by mass,
The 1,4-bond amount of the 3-butadiene polymer block was 60 mol%.
(6) The hydrogenation reaction was performed by adding the reaction product of nickel octylate and triisobutylaluminum to the solution obtained in (5) above as a hydrogenation catalyst and introducing hydrogen into the autoclave. The hydrogenation reaction was carried out for 7 hours after heating to 50 ° C. over 1 hour after introduction of the hydrogenation catalyst. The obtained solution was sufficiently washed with an aqueous solution of citric acid and hydrogen peroxide and water to remove the hydrogenation catalyst, and then the organic layer was poured into an acetone / methanol mixed solvent to precipitate a block copolymer. The resulting block copolymer was thoroughly washed with methanol, 0.1 parts by mass of an antioxidant (“Irganox 1010” manufactured by Ciba Specialty Chemicals) was added, and 6
It vacuum-dried at 0 degreeC and the hydrogenated styrene-type elastomer (A-1) was obtained.

<< Reference Production Example 2 >> Production of Hydrogenated Styrenic Elastomer (A-2) In Reference Production Example 1 above, the same procedure was followed except that the hydrogenation reaction time in step (6) was changed to 4 hours. A styrene elastomer (A-2) was obtained. Table 2 shows the molecular structure of the hydrogenated styrene elastomer (A-2).

<< Reference Production Example 3 >> Production of Hydrogenated Styrenic Elastomer (A-3) Hydrogenated styrenic elastomer in the same manner as Reference Production Example 1 except that phenyl benzoate was not used in step (5). (A-3) was obtained. Table 2 shows the molecular structure of the hydrogenated styrene elastomer (A-3).

<< Reference Production Example 4 >> Production of Block Copolymer (B-1) (1) 118 g of α-methylstyrene, 179 g of cyclohexane, 20 g of hexane and 8 g of tetrahydrofuran were charged into an autoclave sufficiently substituted with nitrogen.
(2) Subsequently, 16.5 mL (21.4 mmol as sec-butyllithium) of a cyclohexane solution of sec-butyllithium was added, and polymerization was performed at -10 ° C for 3 hours. When Mn and Mw / Mn of poly α-methylstyrene 3 hours after the start of polymerization were measured by GPC, Mn = 5100 and Mw / Mn = 1.05, and the polymerization addition rate of α-methylstyrene was 89%. there were.
(3) Next, 20 g of butadiene was added and stirred for 30 minutes, and then the temperature was raised to 10 ° C., and 150 g of cyclohexane was added to dilute the polymerization solution. Subsequently, 193 g of the polymerization solution was extracted, and 640 g of cyclohexane was further added.
(4) Next, 283 g of butadiene was added, and polymerization was carried out at 50 ° C. for 2 hours. When Mn and Mw / Mn of the polymer obtained by sampling at this time were measured by GPC, Mn = 49000 and Mw / Mn = 1.05. The mass fraction of the α-methylstyrene polymer block determined from ¹ H-NMR measurement was 18% by mass, and the amount of 1,4-bond in the polybutadiene portion was 66%.
(5) Subsequently, 30 mL of phenyl benzoate in cyclohexane (6.55 mmol as phenyl benzoate) was slowly added and stirred at 50 ° C. for 1 hour. After stirring, a small amount of degassed methanol was added to complete the polymerization. When the number average molecular weight of the obtained polymer was measured by GPC, it was Mn = 98000 and Mw / Mn = 1.04. The mass fraction of the α-methylstyrene polymer block determined from ¹ H-NMR was 18% by mass, and the 1,4-bond content of the butadiene polymer block was 66%.
(6) After thoroughly washing the obtained polymerization solution with water, the organic layer was poured into an acetone / methanol mixed solvent to precipitate the block copolymer. The obtained block copolymer was thoroughly washed with methanol, 0.1 parts by weight of antioxidant (“Irganox 1010” manufactured by Ciba Specialty Chemicals) was added, and the block copolymer was vacuum-dried at 60 ° C. A polymer (B-1) was obtained.

<< Reference Production Example 5 >> Production of Block Copolymers (B-2) to (B-3) A block copolymer solution was prepared in the same manner as in Reference Production Example 4 until Step (5) in Reference Production Example 4 above. Obtained. A hydrogenation reaction was performed by adding a reaction product of nickel octylate and triisobutylaluminum to the solution as a hydrogenation catalyst and introducing hydrogen into the autoclave. The hydrogenation reaction was carried out at room temperature, and the hydrogenation rate of the block copolymer obtained was controlled by the reaction time. The obtained solution was sufficiently washed with an aqueous solution of citric acid and hydrogen peroxide and water to remove the hydrogenation catalyst, and then the organic layer was poured into an acetone / methanol mixed solvent to precipitate a block copolymer. The resulting block copolymer is thoroughly washed with methanol, 0.1 parts by weight of an antioxidant (“Irganox 1010” manufactured by Ciba Specialty Chemicals) is added, and the block is vacuum-dried at 60 ° C. Copolymers (B-2) and (B-3) were obtained. The molecular structures of (B-2) and (B-3) are shown in Table 3.

Reference Production Example 6 Production of Block Copolymer (B-4) (1) 118 g of α-methylstyrene, 179 g of cyclohexane, 20 g of hexane, and 4 g of tetrahydrofuran were charged into an autoclave sufficiently substituted with nitrogen.
(2) Subsequently, 7.6 mL (9.9 mmol as sec-butyllithium) of a cyclohexane solution of sec-butyllithium was added, and polymerization was performed at −10 ° C. for 3 hours. When Mn and Mw / Mn of poly α-methylstyrene 3 hours after the start of polymerization were measured by GPC, Mn = 11000 and Mw / Mn = 1.04, and the polymerization conversion rate of α-methylstyrene was 90%. there were.
(3) Next, 9.9 g of isoprene was added and stirred for 30 minutes, and then the temperature was raised to 10 ° C., and 300 g of cyclohexane was added to dilute the polymerization solution. Subsequently, 450.2 g of the polymerization solution was extracted, and 800 g of cyclohexane was further added.
(4) Next, 348 g of isoprene was added and polymerization was carried out at 50 ° C. for 2 hours, and then a small amount of degassed methanol was added to complete the polymerization. The obtained polymerization solution was sufficiently washed with water, and then the organic layer was poured into an acetone / methanol mixed solvent to precipitate a block copolymer. The obtained block copolymer was thoroughly washed with methanol, 0.1 parts by weight of antioxidant (“Irganox 1010” manufactured by Ciba Specialty Chemicals) was added, and the block copolymer was vacuum-dried at 60 ° C. A polymer (B-4) was obtained. When Mn and Mw / Mn of the obtained block copolymer (B-4) were measured by GPC, it was Mn = 448000 and Mw / Mn = 1.08.

The following products were used as the block copolymer (B-5).
Block copolymer (B-5): Polystyrene-vinylisoprene-styrene block copolymer (Hibler 5125, styrene content 20%, manufactured by Kuraray Co., Ltd.)

The following products were used as the graft copolymers (C-1), (C-2), and (C-3).
Graft copolymer (C-1): Latex obtained by graft polymerization of 25% by weight of methyl methacrylate on natural rubber, solid content concentration 51% by weight (“Regex MG-25” manufactured by Residex Co., Ltd.)
Graft copolymer (C-2): Latex obtained by graft polymerization of 40% by weight of methyl methacrylate on natural rubber, solid content concentration of 53% by weight (“Regex MG-40S” manufactured by Regex Corp.)
Graft copolymer (C-3): Latex obtained by graft polymerization of 67% by weight of methyl methacrylate on natural rubber, solid content concentration of 51% by weight (“Regex MG-67” manufactured by Residex Co., Ltd.)

<< Examples 1-5 >> Production of Hydrogenated Styrene Elastomer Laminate for Bonding Diene Rubber Rubber Compression molded sheet (thickness 2 mm) of hydrogenated styrene elastomer (A-1) and block copolymer (B-1) A compression molded film (thickness 0.2 mm) of (B-5) was superposed and heat treated at 180 ° C. for 5 minutes to prepare a hydrogenated styrene elastomer laminate for adhering a diene rubber. The produced hydrogenated styrene elastomer laminate for adhering diene rubber was evaluated for tensile strength at break, tensile elongation at break, and adhesion with diene rubber, as shown in Table 5.

<< Examples 6 to 8 >> Production of hydrogenated styrene elastomer laminate for adhering a diene rubber A graft copolymer (C-1) was formed on a compression molded sheet (thickness 2 mm) of a hydrogenated styrene elastomer (A-1). Hydrogenated styrene system for diene rubber adhesion having a graft copolymer layer having a thickness of 0.2 mm on a hydrogenated styrenic elastomer (A-1) sheet after applying the latex of (C-3). A laminate was produced. The produced hydrogenated styrene-based elastomer laminate for adhering diene rubber was evaluated for tensile strength at break, tensile elongation at break, and adhesiveness with diene rubber, as shown in Table 5.

Comparative Reference Example 1 Production of Hydrogenated Styrene Elastomer Laminate Having Composition Containing Unvulcanized Diene Rubber and Vulcanizing Agent as Adhesion Layer Hydrogenated Styrene Elastomer (A-1) Compression Molded Sheet ( 2 mm), polyisoprene (“LIR-50” manufactured by Kuraray Co., Ltd.) 10 g as an unvulcanized diene rubber, and 2,5-dimethyl-2,5-di (t-butylperoxy) as a vulcanizing agent A solution consisting of 1.43 g (5 mmol) of hexyne-3 (Nippon Yushi Co., Ltd. “Perhexine 25B”) and 10 g of n-hexane was applied and dried, and then on a sheet of hydrogenated styrene elastomer (A-1). A hydrogenated styrene elastomer laminate for diene rubber adhesion having a polyisoprene / vulcanizing agent layer having a thickness of 0.2 mm was produced. The produced hydrogenated styrene elastomer laminate for adhering diene rubber was evaluated for tensile strength at break, tensile elongation at break, and adhesiveness with diene rubber, as shown in Table 6.

Comparative Example 1 Hydrogenated Styrenic Elastomer Evaluation of tensile rupture strength, tensile rupture elongation, and adhesion to diene rubber for a compression molded sheet (thickness 2 mm) of hydrogenated styrene elastomer (A-1) It was as shown in Table 6.

Comparative Example 2 Production of Hydrogenated Styrene Elastomer Laminate for Diene Rubber Adhesion A hydrogenated styrene elastomer laminate for diene rubber adhesion was prepared in the same manner as in Reference Production Example 1 except that no vulcanizing agent was used. Manufactured. The produced hydrogenated styrene elastomer laminate for adhering diene rubber was evaluated for tensile strength at break, tensile elongation at break, and adhesiveness with diene rubber, as shown in Table 6.

<< Comparative Examples 3 and 4 >> Production of hydrogenated styrene elastomer laminate for diene rubber adhesion Hydrogenated styrene elastomer (A-2), compression molded sheet (thickness 2 mm) of (A-3), and block weight A compression molded film (thickness: 0.2 mm) of the union (B-1) was superposed and heat treated at 180 ° C. for 5 minutes to prepare a hydrogenated styrene elastomer laminate for diene rubber adhesion. The produced hydrogenated styrene elastomer laminate for adhering diene rubber was evaluated for tensile strength at break, tensile elongation at break, and adhesiveness with diene rubber, as shown in Table 6.

  From Table 5, based on the method disclosed in Patent Document 1, in Comparative Reference Example 1 using a hydrogenated styrene elastomer laminate for diene rubber adhesion having an adhesive layer composed of an unvulcanized rubber and a vulcanizing agent, Adhesiveness is insufficient.

  From Table 5 and Table 6, in Comparative Example 1 in which the hydrogenated styrene-based elastomer does not have any adhesive layer, the adhesiveness is inferior compared with Examples 1 to 8 having an adhesive layer that satisfies the constituent requirements of the present invention. It is enough.

  From Table 5 and Table 6, in Comparative Example 2 in which the adhesive layer does not satisfy the constituent requirements of the present invention, the adhesiveness is inferior compared with Examples 6 to 8 having the adhesive layer satisfying the constituent requirements of the present invention, and sufficient. It is hard to say that there is.

  From Table 5 and Table 6, in Comparative Example 3 in which the hydrogenated styrene-based elastomer does not satisfy the constituent requirements of the present invention, compared with Example 1 in which the hydrogenated styrene-based elastomer satisfies the constituent requirements of the present invention, The tensile strength at break of the body is insufficient, which is not preferable.

  Furthermore, from Table 5 and Table 6, in Comparative Example 4 in which the hydrogenated styrene elastomer does not satisfy the constituent requirements of the present invention, the mechanical strength of Example 1 in which the hydrogenated styrene elastomer satisfies the constituent requirements of the present invention is increased. In addition, the adhesiveness is lowered, and it cannot be said that the laminate has a sufficient practical strength.

  From Table 5, Example 1 in which the hydrogenation rate is less than 20 mol% compared to Example 3 in which the hydrogenation rate of the polymer block (i) of the block copolymer used for the adhesive layer is 20 mol% or more. In 2, 4, and 5, it can be seen that higher adhesiveness is obtained, which is more preferable.

  According to the present invention, there is provided a hydrogenated styrene elastomer laminate for adhering a diene rubber that is excellent in adhesion to a diene rubber and mechanical properties.

Claims (2)

It has one or more polymer blocks (i) composed of conjugated diene compound units and two or more polymer blocks (ii) composed of vinyl aromatic compound units, and the carbon-carbon defect contained in the polymer block (i). A hydrogenated styrenic elastomer layer comprising a block copolymer (A) in which 90 mol% or more of saturated double bonds are hydrogenated;
An adhesive layer comprising a conjugated diene copolymer selected from a block copolymer (B) or a graft copolymer (C) having a conjugated diene polymer in at least a part of the main chain;
A hydrogenated styrene-based elastomer laminate for adhering a diene rubber ,
The block copolymer (B) has one or more polymer blocks (iii) composed of conjugated diene compound units and one or more polymer blocks (iv) composed of vinyl aromatic compound units, or
The graft copolymer (C) is one or more diene rubbers selected from natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, styrene-isoprene rubber, styrene-butadiene-isoprene rubber, and nitrile-butadiene rubber. A hydrogenated styrene elastomer laminate for adhering a diene rubber, which is a (meth) acrylic ester grafted diene rubber obtained by graft polymerization of a (meth) acrylic acid ester to the main chain.  The hydrogenated styrene-based elastomer laminate for bonding a diene rubber according to claim 1, wherein the vinyl aromatic compound unit constituting the polymer block (ii) of the block copolymer (A) is an α-methylstyrene unit.