JP2011184594A - Crosslinked composition, process for production thereof, and molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crosslinked composition and a molded article excellent in flexibility, heat resistance (permanent compression strain at high temperatures), mechanical strength, and molding processability. <P>SOLUTION: The crosslinked composition is obtained by crosslinking a composition comprising (I) 1-99 pts.mass of a vinyl aromatic copolymer rubber containing 5-70 mass% of a vinyl aromatic monomer unit and 0.1-30 mass% of a conjugated diene monomer unit, and (II) 99-1 pts.mass of an ethylenic copolymer rubber, as well as, based on 100 pts.mass of the total amount of the vinyl aromatic copolymer rubber (I) and the ethylenic copolymer rubber (II), (III) 10-100 pts.mass of an olefinic resin, and (IV) 0.01-50 pts.mass of a crosslinker. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a crosslinked composition, a method for producing the crosslinked composition, and a molded body.

Conventionally, among thermoplastic elastomers, styrene series such as styrene-butadiene block copolymer (SBS), which is a block copolymer of vinyl aromatic compound-conjugated diene compound, and styrene-isoprene block copolymer (SIS). Thermoplastic elastomers are rich in flexibility and have good rubber elasticity and processability at room temperature, and thermoplastic elastomer compositions containing them are widely used as substitutes for vulcanized rubber.
The thermoplastic elastomer composition in which the double bond portion in the thermoplastic elastomer composition is hydrogenated is a substitute for vulcanized rubber as a thermoplastic elastomer having improved heat aging resistance (thermal stability) and weather resistance. More widely used as a product.
However, thermoplastic elastomer compositions using these hydrogenated block copolymers still have improved rubber-like properties such as oil resistance, heat-pressing deformation rate (compression set) and rubber elasticity at high temperatures. There is a problem that there is room for it.

  In view of this, a crosslinking composition obtained by crosslinking a hydrogenated derivative of the block copolymer has been proposed as a means for improving the above characteristics (see, for example, Patent Documents 1 to 5).

Many thermoplastic elastomer compositions obtained by dynamically crosslinking an olefin resin and an olefin copolymer rubber are also known.
For example, an elastomer composition obtained by dynamically crosslinking an ethylene copolymer resin such as an ethylene-vinyl acetate copolymer and a rubber such as a halogenated butyl rubber (for example, see Patent Document 6), an ethylene-vinyl acetate copolymer, and the like. An elastomer composition containing an EPDM rubber (ethylene-propylene-diene rubber) dynamically vulcanized in the presence of an ethylene copolymer resin (see, for example, Patent Document 7), an ethylene-hexene copolymer, and an ethylene-butene copolymer. An elastomer composition containing a halogenated butyl rubber dynamically vulcanized in the presence of a polymer (see, for example, Patent Document 8), an α-monoolefin copolymer rubber such as EPDM and crystalline polypropylene, etc. Composition containing thermoplastic elastomer obtained by vulcanization of mixture and low-density ethylene-α-olefin copolymer Products (for example, see Patent Document 9), vulcanized EPDM and crystalline ethylene polymer blended, and then a free-radical cross-linked molded article (for example, see Patent Document 10), EPDM and crystalline polypropylene A composition containing a thermoplastic elastomer obtained by vulcanizing a mixture of the polymer and high-density polyethylene and low-density polyethylene (see, for example, Patent Document 11), a crosslinkable rubber such as a terpolymer rubber, and a heat such as polypropylene. An elastomer (for example, see Patent Document 12) obtained by crosslinking a mixture of a plastic resin and a highly fluid linear polyolefin processing additive is disclosed.

  Further, by using a combination of an olefin elastomer and a saturated styrene elastomer (SEEPS, etc.), a thermoplastic elastomer composition which is excellent in compression set and molding processability in a high temperature region and which is flexible and free from oil bleed. It has been proposed (see, for example, Patent Document 13).

JP 59-6236 A JP-A 63-57662 Japanese Patent Publication No. 3-49927 Japanese Patent Publication No. 3-11291 Japanese Patent Publication No. 6-13628 Japanese Examined Patent Publication No. 61-26641 Japanese Patent Laid-Open No. 2-113046 JP-A-3-17143 JP-A-3-234744 Japanese Patent Laid-Open No. 1-132643 JP-A-2-255733 JP 2002-220493 A Japanese Patent No. 4231367

However, the crosslinked compositions of hydrogenated block copolymers disclosed in Patent Documents 1 to 5 are still insufficient in compression set at a high temperature of 100 ° C. or higher, and further the mechanical strength is lowered. There is a problem that it is easy, and there is a problem that the performance level required for vulcanized rubber applications is not reached.
In addition, the compositions disclosed in Patent Documents 6 to 12 also have a high compression set at a high temperature, and the compression set at a short-term and long-term high temperature reaches the performance level required for conventional vulcanized rubber applications. Not.
Furthermore, the olefin elastomers disclosed in the above-mentioned Patent Documents 6 to 12 have low oil retention and the hardness is limited to 50 to 90A, and a softening agent for rubber is added to the olefin elastomer to improve flexibility. When trying to obtain, the bleed of the softening agent from the molded product is remarkable, and those exhibiting flexibility of 50 A or less have the disadvantage that extrusion / injection moldability is poor and cannot be used for applications requiring flexibility.

  Furthermore, in a cross-linking composition using both an olefin elastomer component and a styrene elastomer component as disclosed in Patent Document 13, an olefin component having an unsaturated bond and a saturated styrene component are used. There is a problem that the difference in cross-linking reaction rate is large, and cross-linking unevenness, rough skin and poor appearance of the cross-linked composition, mechanical properties and compression set are often reduced.

  Therefore, in the present invention, in view of the above-mentioned problems of the prior art, a crosslinked composition having excellent flexibility, heat resistance (compression set at high temperature), mechanical strength, and excellent moldability is provided. The purpose is to do.

As a result of intensive studies to solve the above-mentioned problems of the prior art, the present inventors have found that a vinyl aromatic copolymer rubber (hydrogenated block copolymer) (I) having a specific block structure, an ethylene-based copolymer The present inventors have found that a crosslinking composition containing a copolymer rubber (II), an olefinic resin (III), and a crosslinking agent (IV) can solve the above-mentioned problems of the prior art, and have made the present invention.
That is, the present invention is as follows.

[1]
(I) vinyl aromatic copolymer rubber containing 5-70% by mass of vinyl aromatic monomer unit and 0.1-30% by mass of conjugated diene monomer unit: 1-99 parts by mass,
(II) ethylene copolymer rubber: 99 to 1 part by mass;
Containing,
Total amount of the (I) vinyl aromatic copolymer rubber and the (II) ethylene copolymer rubber: 100 parts by mass,
(III) Olefin resin: 10 to 100 parts by mass;
(IV) Crosslinking agent: 0.01 to 50 parts by mass;
Is a crosslinked composition obtained by crosslinking a composition containing

[2]
The crosslinking composition according to [1], wherein the (I) vinyl aromatic copolymer rubber has a conjugated diene monomer block at a terminal portion.

[3]
[1] The vinyl aromatic copolymer rubber (I) is a hydrogenated vinyl aromatic block copolymer comprising a vinyl aromatic monomer unit and a conjugated diene monomer unit. The crosslinked composition as described.

[4]
(V) The rubber softener is a total amount of the (I) vinyl aromatic copolymer rubber and the (II) ethylene copolymer rubber: 1 to 300 parts by mass with respect to 100 parts by mass, Furthermore, the crosslinked composition according to any one of [1] to [3].

[5]
The crosslinked composition according to any one of [1] to [4], wherein the (II) ethylene copolymer rubber is ethylene-propylene-nonconjugated diene copolymer rubber (EPDM).

[6]
The crosslinking composition according to any one of [1] to [5], wherein the (III) olefin-based resin is polypropylene.

[7]
(I) vinyl aromatic copolymer rubber containing 5-70% by mass of vinyl aromatic monomer unit and 0.1-30% by mass of conjugated diene monomer unit: 1-99 parts by mass,
(II) ethylene copolymer rubber: 99 to 1 part by mass;
Total amount of the (I) vinyl aromatic copolymer rubber and the (II) ethylene copolymer rubber: 100 parts by mass,
(III) Olefin resin: 10 to 100 parts by mass;
(IV) Crosslinking agent: 0.01 to 50 parts by mass;
A method for producing a crosslinked composition comprising the steps of mixing and dynamically crosslinking under melting conditions.

[8]
The molded object which shape | molded the crosslinked composition as described in any one of said [1] thru | or [6].

  According to the present invention, a crosslinked composition having excellent flexibility, heat resistance, mechanical strength, and excellent moldability can be obtained.

  Hereinafter, although the form for implementing this invention (henceforth "this embodiment") is demonstrated, this invention is not limited to the form shown below.

(Crosslinked composition)
The crosslinking composition of the present embodiment is
(I) vinyl aromatic copolymer rubber containing 5-70% by mass of vinyl aromatic monomer unit and 0.1-30% by mass of conjugated diene monomer unit: 1-99 parts by mass,
(II) ethylene copolymer rubber: 99 to 1 part by mass;
Containing,
Total amount of the (I) vinyl aromatic copolymer rubber and the (II) ethylene copolymer rubber: 100 parts by mass,
(III) Olefin resin: 10 to 100 parts by mass;
(IV) Crosslinking agent: 0.01 to 50 parts by mass;
Is a crosslinked composition obtained by crosslinking a composition containing

In this specification, the naming of each monomer unit constituting the polymer follows the naming of the monomer from which the monomer unit is derived.
For example, “vinyl aromatic monomer unit” means a structural unit of a polymer resulting from polymerization of a vinyl aromatic compound as a monomer, and the structure thereof is a substituted ethylene group derived from a substituted vinyl group. This is a molecular structure in which the two carbons are binding sites.
In addition, the “conjugated diene monomer unit” means a structural unit of a polymer resulting from polymerization of a conjugated diene monomer, and the structure thereof includes two olefins derived from a conjugated diene monomer. It is a molecular structure in which carbon is the binding site.

<(I) Vinyl aromatic copolymer rubber>
(I) The vinyl aromatic copolymer rubber contains 5-70% by mass of vinyl aromatic monomer units and 0.1-30% by mass of conjugated diene monomer units.
(I) As vinyl aromatic copolymer rubber, polymer block A mainly composed of vinyl aromatic monomer units and polymer block mainly composed of conjugated diene monomer units having 5 or more carbon atoms 1 or more B, and 1 or more polymer blocks C mainly composed of conjugated diene monomer units different from the conjugated diene monomer units constituting the polymer block B having 4 or more carbon atoms A vinyl aromatic block copolymer obtained by hydrogenation and having one or more unsaturated blocks at the end is preferred.

In this specification, “mainly” means that a predetermined monomer unit is contained in a predetermined block in an amount of 60% by mass or more, preferably 70% by mass or more, and more preferably 80% by mass or more. preferable. For example, in the case of “polymer block mainly composed of A units”, the polymer block contains 60% by mass or more of A (monomer) units.
Moreover, in this specification, when it has the polymer block A at the terminal of a polymer chain and the terminal of a polymer chain, the "terminal part" also includes the adjacent part. For example, when the polymer block B is included as an unsaturated block and has a structure such as A—B—C—B—A, the “polymer block B exists at the end”. That is, in this example, the polymer block B is adjacent to the polymer block A which is a hard segment, or the terminal block is a conjugated diene monomer unit having 5 or more carbon atoms and a vinyl aromatic monomer. It means a random copolymer block (A / B) mainly composed of units.

The content of the polymer block A in the (I) vinyl aromatic copolymer rubber is as follows: (I) vinyl aromatic copolymer rubber from the viewpoint of mechanical properties and rubber properties of the vinyl aromatic copolymer rubber. The content is preferably 5% by mass to 70% by mass with respect to the total mass of the aromatic copolymer rubber. (I) From the viewpoint of flexibility and rubbery characteristics of the vinyl aromatic copolymer rubber, The combined block A is preferably 70% by mass or less.
On the other hand, from the viewpoints of (I) vinyl aromatic copolymer rubber and the handling property (non-tack property), productivity, and processability of the target crosslinked composition, the polymer block A is 5% by mass or more. It is preferable.
The content of the polymer block A in the (I) vinyl aromatic copolymer rubber is more preferably in the range of 10% by mass to 60% by mass, further preferably in the range of 12% by mass to 50% by mass, The range of mass% to 40 mass% is even more preferable.

As described above, the polymer block B is a polymer block mainly composed of a conjugated diene monomer unit having 5 or more carbon atoms, and a plurality of types of conjugated diene monomers having 5 or more carbon atoms. Random copolymerization with units may be used, and these conjugated diene monomer units may be uniformly distributed in the polymer block B or may be non-uniformly (for example, tapered). A plurality of uniformly distributed portions and / or non-uniformly distributed portions may coexist in the polymer block B.
The polymer block B is more preferably a complete block copolymer of 5 or more conjugated diene monomer units from the viewpoint of compression set of the crosslinked composition.
(I) As content of polymer block B in vinyl aromatic copolymer rubber, it is 0.1 mass%-20 mass with respect to the total mass of (I) vinyl aromatic copolymer rubber. % Is preferred.
Since the polymer block B is a block containing an unsaturated bond, from the viewpoint of oxidation stability, thermal stability, productivity, and processability, (I) the total mass of the vinyl aromatic copolymer rubber On the other hand, it is preferably 20% by mass or less, preferably 0.1% by mass or more from the viewpoint of crosslinking reactivity, more preferably in the range of 0.5% by mass to 15% by mass, and further in the range of 1% by mass to 10% by mass. preferable.

The polymer block C is a polymer block mainly composed of a conjugated diene monomer unit having 4 or more carbon atoms, and is different from the conjugated diene monomer unit constituting the polymer block B. Random copolymerization with a plurality of conjugated diene monomer units having 4 or more carbon atoms may be used, and these conjugated diene monomer units may be uniformly distributed in the polymer block C. Further, it may be distributed non-uniformly (for example, tapered).
A plurality of uniformly distributed portions and / or non-uniformly distributed portions may coexist in the polymer block C.
The polymer block C is more preferably a complete block copolymer of 4 or more conjugated diene monomer units from the viewpoint of compression set.
The content of the polymer block C is preferably 10 to 85% by mass relative to the total mass of the (I) vinyl aromatic copolymer rubber in the state before hydrogenation, and the productivity and processability From the viewpoint of the above, it is more preferably 25 to 85% by mass.
In the polymer block C, the unsaturated bond disappears by hydrogenation, so that the amount of the polymer block C contained in the (I) vinyl aromatic copolymer rubber is not so large.
The hydrogenation rate of the polymer block C is preferably 80% or more, more preferably 85% or more, further preferably 90% or more, and more preferably 95% or more from the viewpoint of oxidation stability, thermal stability, and elongation at break. More preferred.

(I) As a vinyl aromatic block copolymer in a state before hydrogenation of a vinyl aromatic copolymer rubber, for example, a linear block represented by a general formula: H— (C—H) _n Copolymer, or linear block copolymer represented by the general formula: [(HC) _k ] _m- X, [H- (CH) _k ] _m- X, or radial block copolymer Coalescence is mentioned.
In the above general formulas, H is a single block of A, a single block of B, a block copolymer of AB or B-A, or a conjugated diene monomer unit having 5 or more carbon atoms and a vinyl aromatic unit. A random copolymer block (A / B) mainly composed of a monomer unit is shown.
A plurality of H in the formula may be the same or different.
For example, an A-B-C-A-B type block structure is also included.
N and k are integers of 1 to 5, and m is an integer of 2 to 6.
X represents a residue of a coupling agent or a residue of a polyfunctional initiator.
The plurality of polymer blocks A and polymer blocks B present in the copolymer may have the same or different structures such as molecular weight and composition.

Although the mass ratio of the polymer block A mainly composed of the vinyl aromatic monomer unit contained in the polymer block H and the polymer block B is not particularly limited, (I) of the vinyl aromatic copolymer rubber From the viewpoint of stickiness, polymer fusion (blocking), productivity, and compression set, the polymer block A is 60% by mass or more with respect to the polymer block H, that is, the polymer block B is 40% by mass or less. The polymer block A is 99% by mass or less, that is, the polymer block B is 1% by mass from the viewpoint that (I) the vinyl aromatic copolymer rubber has a large number of unsaturated groups and has high crosslinking reactivity. Preferably, the ratio (B / H) of the polymer block B is 5 to 25% by mass. More preferably, it is 7-20 mass%. This is because the polymer block B has a feature that it is hardly hydrogenated.
H is preferably a complete block copolymer of AB or B-A in terms of compression set.

The (I) vinyl aromatic copolymer rubber preferably has one or more unsaturated blocks at the end, and more preferably has two or more unsaturated blocks.
The “unsaturated block” is a polymer block having an olefinically unsaturated double bond, mainly composed of the above-described polymer block B (conjugate diene monomer unit having 5 or more carbon atoms). Polymer block), the hydrogenation rate of the double bond of the conjugated diene monomer unit which is an olefinically unsaturated double bond is lower than that of the polymer block C, and the unsaturated bond in the block The existence ratio is large.
Therefore, it is necessary to select a conjugated diene monomer unit used for the polymer block B having a slower hydrogenation rate than the conjugated diene monomer unit used for the polymer block C.

When the polymer block H is a random copolymer block (A / B) mainly composed of a conjugated diene monomer unit having 5 or more carbon atoms and a vinyl aromatic monomer unit. The polymer block is also included in the “unsaturated block”.
Here, “random” may mean that two or more types of monomer units may be uniformly distributed or non-uniformly (for example, tapered).

(I) The vinyl aromatic copolymer rubber preferably has one or more unsaturated blocks between a terminal hard segment and an internal soft segment.
For example, (I) a vinyl aromatic copolymer rubber has a polymer block A mainly composed of vinyl aromatic monomer units at both ends as a hard segment, and next to it, that is, a hard segment and Hydrogenating a non-hydrogenated block copolymer of the type containing a polymer block B mainly composed of a conjugated diene monomer unit having 5 or more carbon atoms, which is an unsaturated block, between the internal soft segment. When the hydrogenated block copolymer is obtained, the microphase separation becomes clearer and the cohesive force of the polymer block A mainly composed of vinyl aromatic monomer units becomes stronger. I) It is preferable because the stickiness and compression set of the vinyl aromatic copolymer rubber are improved.
(I) The vinyl aromatic copolymer rubber contains a polymer block B mainly composed of a plurality of conjugated diene monomer units having 5 or more carbon atoms, not only at both ends but also in the molecular chain. A structure of the type is preferable because oil resistance and compression set are improved in the crosslinked product.

  Examples of the vinyl aromatic hydrocarbon constituting the (I) vinyl aromatic copolymer rubber include, for example, styrene, o-methyl styrene, p-methyl styrene, p-tert-butyl styrene, 1,3-dimethyl styrene. , Α-methylstyrene, vinyl naphthalene, vinyl anthracene and the like. These may be used alone or in combination of two or more. Styrene is particularly preferable.

The (I) conjugated diene constituting the vinyl aromatic copolymer rubber is a diolefin having a pair of conjugated double bonds.
Examples of the conjugated diene contained in the polymer block B described above include isoprene, 2,3-dimethyl-butadiene, 2-methyl-1,3-pentadiene, myrcene, 2-methyl-1,3-pentadiene, 3- Methyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 2-phenyl-1,3-butadiene, 2-phenyl-1,3-pentadiene, 3-phenyl-1,3-pentadiene, 2, 3-dimethyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 2-hexyl-1,3-butadiene, 3-methyl-1,3-hexadiene, 2-benzyl-1,3-butadiene, One or more of 2-p-tolyl-1,3-butadiene, 1,3-cyclohexadiene, or a mixture thereof can be used, and isoprene, 1,3-cyclohexadiene is preferred.

  Examples of the conjugated diene contained in the polymer block C described above include 1,3-butadiene, 1,3-pentadiene, 2,4-hexadiene, 1,3-hexadiene, 1,3-heptadiene, 2,4. -Heptadiene, 1,3-octadiene, 2,4-octadiene, 3,5-octadiene, 1,3-nonadiene, 2,4-nonadiene, 3,5-nonadiene, 1,3-decadiene, 2,4-decadiene , 3,5-decadiene, 1,3-cyclohexadiene, or a mixture thereof can be used alone or in combination, and 1,3-butadiene is preferred. From the viewpoint of compression set, the polymer block C is preferably a conjugated diene single block.

  The conjugated diene used in the polymer blocks B and C preferably has 15 or less carbon atoms.

  (I) As the remaining components other than the “main component” contained in the polymer block constituting the vinyl aromatic copolymer rubber, all monomer species having anion polymerizable properties are applicable.

  The (I) vinyl aromatic copolymer rubber constituting the crosslinked composition of the present embodiment is a polymer block having an unsaturated block at the end portion as described above, that is, an olefinically unsaturated double bond, The above-mentioned polymer block B (in the case of using a structure having a polymer block mainly composed of a conjugated diene monomer unit having 5 or more carbon atoms, exhibits extremely excellent heat resistance. It is not limited to such special structures.

  A block copolymer consisting of 5 to 70% by mass of a vinyl aromatic monomer unit and a conjugated diene monomer unit is hydrogenated, and the remaining conjugated diene monomer unit is not hydrogenated. If it is contained in an amount of 0.1 to 30% by mass, it is effective for improving heat resistance and mechanical strength by using it as (I) vinyl aromatic copolymer rubber. In the case of emphasis, the latter, ie, a block copolymer comprising 5 to 70% by mass of vinyl aromatic monomer units and a conjugated diene monomer unit is hydrogenated and remains without being hydrogenated. Those having 0.1 to 30% by mass of conjugated diene monomer units are more advantageous.

  The above-mentioned conjugated diene monomer, which is obtained by hydrogenating a block copolymer consisting of 5-70% by mass of vinyl aromatic monomer units and a conjugated diene monomer unit Examples of vinyl aromatic hydrocarbons containing 0.1 to 30% by mass of units include styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethyl. Examples thereof include styrene, α-methylstyrene, vinyl naphthalene, vinyl anthracene, and one or more of these can be used, and styrene is preferable.

  Conjugated dienes constituting the above are 1,3-butadiene, 1,3-pentadiene, 2,4-hexadiene, 1,3-hexadiene, 1,3-heptadiene, 2,4-heptadiene, 1,3-octadiene 2,4-octadiene, 3,5-octadiene, 1,3-nonadiene, 2,4-nonadiene, 3,5-nonadiene, 1,3-decadiene, 2,4-decadiene, 3,5-decadiene, 1 , 3-cyclohexadiene, isoprene, 2,3-dimethyl-butadiene, 2-methyl-1,3-pentadiene, myrcene, 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 4- Methyl-1,3-pentadiene, 2-phenyl-1,3-butadiene, 2-phenyl-1,3-pentadiene, 3-phenyl-1,3-pentadiene 2,3-dimethyl-1,3-pentadiene, 4-methyl-1,3-pentadiene, 2-hexyl-1,3-butadiene, 3-methyl-1,3-hexadiene, 2-benzyl-1, Examples include 3-butadiene, 2-p-tolyl-1,3-butadiene, 1,3-cyclohexadiene, and one or more of them can be used, and 1,3-butadiene and isoprene are preferable.

  Specific examples of the vinyl aromatic copolymer rubber (I) having the structure as described above include styrene-butadiene block copolymer (SBR), styrene-butadiene-styrene block copolymer (SBS), and styrene. -Hydrogenated product such as isoprene-styrene block copolymer (SIS), which leaves 0.1 to 30% by mass of the conjugated diene in a non-hydrogenated state.

The weight average molecular weight of the above (I) vinyl aromatic copolymer rubber can be measured by polystyrene conversion using gel permeation chromatography (GPC), and the productivity, workability, mechanical strength, compression set From the viewpoint of balance, it is preferably 5,000 to 2,000,000, more preferably 10,000 to 1,000,000, still more preferably 30,000 to 500,000.
(I) Molecular weight distribution (Mw / Mn) of vinyl aromatic copolymer rubber (ratio of weight average molecular weight (Mw) to number average molecular weight (Mn)) is from the viewpoint of balance between workability and mechanical strength. Preferably it is 10 or less, More preferably, it is 1.01-5, More preferably, it is 1.01-2.
The weight average molecular weight is measured by gel permeation chromatography (GPC), and the molecular weight of the chromatogram peak is prepared using a calibration curve obtained from the measurement of commercially available standard polystyrene (using the peak molecular weight of standard polystyrene). ) Was used to determine the weight average molecular weight.
The molecular weight distribution of the hydrogenated block copolymer can be similarly determined from the measurement by GPC.

The microstructure (cis, trans, vinyl ratio) of the conjugated diene monomer unit portion in the block copolymer before hydrogenation of the above (I) vinyl aromatic copolymer rubber is polar The amount of 1,2-vinyl bond is generally 5 to 90% by mass, and isoprene is used as the conjugated diene when 1,3-butadiene is used as the conjugated diene. In some cases, the 3,4-vinyl bond content is generally 3-80% by weight.
However, from the viewpoint of productivity, when 1,3-butadiene is used as the conjugated diene, the 1,2-vinyl bond content is preferably 10 to 80% by mass, more preferably 20 to 75% by mass, 25 -75 mass% is more preferable.
When isoprene is used as the conjugated diene, the 3,4-vinyl bond content is preferably 5 to 70% by mass.

The vinyl aromatic monomer unit content in the (I) vinyl aromatic copolymer rubber can be determined using an ultraviolet spectrophotometer or the like.
The conjugated diene monomer unit content, the vinyl bond content based on the conjugated diene monomer unit, and the hydrogenation rate can be determined by using a nuclear ceramic resonance apparatus (NMR).
The molecular weight of the vinyl aromatic monomer unit homopolymer block is determined by a method of oxidative decomposition with di-tert-butyl hydroperoxide using osmium tetroxide as a catalyst (IM KOLTHOFF, et-al., J. Polym. Sci. 1, 429 (1946)), vinyl aromatic monomer unit homopolymer block component obtained by decomposing the block copolymer before hydrogenation (however, components having a polymerization degree of 30 or less have been removed) ) Ultraviolet spectrophotometer or GPC measurement. Moreover, the content can be calculated | required using an ultraviolet spectrophotometer.
The above (I) vinyl aromatic copolymer rubber may be produced by a known method, for example, Japanese Patent Publication No. 36-19286, Japanese Patent Publication No. 43-171979, Japanese Patent Publication No. 46-32415, JP-B-49-36957, JP-B-48-2423, JP-B-48-4106, JP-B-56-28925, JP-B-51-49567, JP-A-59-166518, JP Examples thereof include the method described in JP-A-60-186577.

<(II) Ethylene copolymer rubber>
As the (II) ethylene copolymer rubber in the crosslinkable composition of the present embodiment, an elastomer obtained by copolymerizing ethylene and an α-olefin such as propylene, 1-butene, 1-pentene, etc. An ethylene copolymer rubber formed by copolymerization with a conjugated diene is exemplified.
Examples of the non-conjugated diene include 5-ethylidene-2-norbornene (ENB), 1,4-hexadiene, 5-methylene-2-norbornene (MNB), 1,6-octadiene, and 5-methyl-1,4. -Hexadiene, 3,7-dimethyl-1,6-octadiene, 1,3-cyclopentadiene, 1,4-cyclohexadiene, tetrahydroindene, methyltetrahydroindene, dicyclopentadiene, 5-isopropylidene-2-norbornene, 5 -Vinyl-norbornene, dicyclooctadiene, methylene norbornene and the like.

(II) Examples of the ethylene copolymer rubber include ethylene-propylene copolymer rubber, ethylene-propylene-nonconjugated diene copolymer rubber, ethylene-1-butene copolymer rubber, ethylene-1-butene- Non-conjugated diene copolymer rubber, ethylene-propylene-1-butene copolymer rubber and the like can be mentioned.
Among these, ethylene-propylene-nonconjugated diene copolymer rubber (EPDM) is preferable from the viewpoint of crosslinkability.

Moreover, the range of ethylene content of (II) ethylene-type copolymer rubber has preferable 40-80 mass%, and 50-75 mass% is more preferable. In particular, in the range of 60 to 75% by mass, the balance between manufacturability, compression set at high temperature, and tensile strength is good, which is very preferable.
Moreover, 0.5-8 mass% is preferable and, as for non-conjugated diene content of (II) ethylene-type copolymer rubber, 4-8 mass% is more preferable. If it is less than 0.5% by mass, the expression of compression set due to crosslinking is insufficient.

(II) The Mooney viscosity ML _{1 + 4} (125 ° C.) of the ethylene copolymer rubber is preferably 10 to 180, and more preferably 20 to 150.
(II) When the Mooney viscosity ML _{1 + 4} (125 ° C.) of the ethylene copolymer rubber is less than 10, the compression set of the crosslinked composition of the present embodiment is lowered. On the other hand, if it exceeds 180, moldability deteriorates.

(II) The addition amount of the ethylene copolymer rubber is 1 to 99 parts by mass when the (I) vinyl aromatic copolymer rubber + the (II) ethylene copolymer rubber = 100 parts by mass. .
By using together (I) vinyl aromatic copolymer rubber and (II) ethylene copolymer rubber, the crosslinked rubber particles formed by dynamic crosslinking can be effectively finely dispersed. , Mechanical strength and compression set can be improved.
The smaller the size of the crosslinked rubber particles dispersed in the matrix formed by the olefin resin, the more the compression set and mechanical strength tend to be improved.
The dispersed crosslinked rubber particle size is preferably 1 μm or less, and more preferably 0.5 μm or less. 0.3 μm or less is more preferable, and 0.1 μm or less is even more preferable.

  In addition, (I) the vinyl aromatic copolymer rubber contains 0.1 to 30% by mass of a conjugated diene monomer unit, so that the crosslinking rate of the ethylene copolymer rubber (II) is increased. As a result, it is possible to suppress deterioration in cross-linking unevenness, rough skin and poor appearance of the cross-linked composition, mechanical properties, compression set, and the like.

<(III) Olefin resin>
As olefin resin (III) contained in the crosslinked composition of this embodiment, crystalline olefin resin is preferable.
The addition amount of the crystalline olefin-based resin is 10 to 100 parts by mass, preferably 15 to 80 parts by mass, and more preferably 20 to 60 parts by mass with respect to (I) + (II) = 100 parts by mass. .
When the content ratio of the olefin resin (III) is less than 10 parts by mass, the thermoplasticity of the crosslinked composition becomes insufficient and the molding processability becomes inferior.
On the other hand, when the amount is more than 100 parts by mass, the flexibility of the crosslinked composition is insufficient.

Examples of the olefin resin (III) contained in the crosslinked composition of the present embodiment include a crystalline ethylene or propylene homopolymer, or a crystalline copolymer mainly composed of ethylene or propylene.
For example, crystalline ethylene polymers such as high density polyethylene, low density polyethylene, ethylene butene-1 copolymer, crystals such as isotactic polypropylene, propylene / ethylene copolymer, propylene / butene-1 copolymer A propylene-based polymer. Of these, propylene-based resins are preferred.

<(IV) Crosslinking agent>
The addition amount of the crosslinking agent (IV) in the crosslinking composition of the present embodiment is 0.01 to 50 parts by mass and 0.05 to 40 parts by mass with respect to (I) + (II) = 100 parts by mass. Part is preferable, and 0.1 to 30 parts by mass is more preferable.
If the amount of the crosslinking agent (IV) used is less than 0.01 parts by mass, sufficient crosslinking cannot be formed in the crosslinked composition, while if more than 50 parts by mass, rubber softening The bleed out of the agent (V), the deterioration of mechanical properties, etc. occur.

The kind in particular of crosslinking agent (IV) is not restrict | limited, A conventionally well-known crosslinking agent can be utilized.
Examples include organic peroxides, sulfur compounds, phenol resin compounds, quinoid compounds, bismaleimide compounds, isocyanate compounds, thiuram compounds, morpholine disulfide, and hydrosilicon compounds, and more. If necessary, crosslinking aids such as stearic acid, oleic acid, zinc stearate, and zinc oxide, co-crosslinking agents, vulcanization accelerators, and the like can be used in combination.
As the crosslinking aid, conventionally known crosslinking aids can be used. For example, the number of repeating units of ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and ethylene glycol is 9. Polyfunctional methacrylate compounds such as polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, -14, 2-methyl-1,8-octanediol dimethacrylate, 1,9-nonanediol dimethacrylate Acrylate, ethoxylated cyclohexanedimethanol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate Polyfunctional acrylate compounds such as propylene glycol diacrylate, vinyl butyrate, vinyl stearate, may be mentioned divinylbenzene, polyfunctional vinyl compounds, such as triallyl cyanurate.
These may be used alone or in combination of two or more.
By such a compound, a uniform and efficient crosslinking reaction can be expected.

<(V) Rubber softener>
The crosslinked composition of the present embodiment may further contain 1 to 300 parts by mass of the rubber softener (V) with respect to (I) + (II) = 100 parts by mass.
The type of the rubber softener (V) is not particularly limited, and any of mineral oil and / or synthetic resin can be used.
Mineral oil softeners are generally a mixture of aromatic hydrocarbons and non-aromatic hydrocarbons (naphthenic hydrocarbons and paraffinic hydrocarbons), where the number of carbon atoms in the paraffinic hydrocarbon is within the total number of carbon atoms. The oils that account for more than 50% of the total are called paraffinic oils, while naphthenic hydrocarbons with 30-45% carbon atoms are called naphthenic oils, and aromatic hydrocarbons with 35% carbon atoms. The above is called aromatic oil.

Among these, the rubber softener preferably used in the present invention is paraffinic oil.
Examples of the compound constituting the paraffinic softener include paraffinic compounds having 4 to 155 carbon atoms, preferably paraffinic compounds having 4 to 50 carbon atoms, specifically, butane, pentane, hexane. , Heptane, octane, nonane, decane, undecane, dodecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nonadecane, eicosan, heneicosan, docosan, tricosan, tetracosan, pentacosan, hexacosan, heptacosan, octacosan, triacotan, henakosan, triacontane, N-paraffins (linear saturated hydrocarbons) such as Contan, Dotriacontane, Pentatriacontane, Hexacontane, Heptacontane, etc., Isobutane, Isopentane, Neopentane, Isohexane, Pentane, neohexane, 2,3-dimethylbutane, 2-methylhexane, 3-methylhexane, 3-ethylpentane, 2,2-dimethylpentane, 2,3-dimethylpentane, 2,4-dimethylpentane, 3, 3-dimethylpentane, 2,2,3-trimethylbutane, 3-methylheptane, 2,2-dimethylhexane, 2,3-dimethylhexane, 2,4-dimethylhexane, 2,5-dimethylhexane, 3,4 -Dimethylhexane, 2,2,3-trimethylpentane, isooctane, 2,3,4-trimethylpentane, 2,3,3-trimethylpentane, 2,3,4-trimethylpentane, isononane, 2-methylnonane, isodecane, Isoundecane, isododecane, isotridecane, isotetradecane, isopentadecane, isoeo Tadekan, Isonanodekan, isoeicosane, 4-ethyl-5-isoparaffins methyl octane (branched saturated hydrocarbons) and can include derivatives of these saturated hydrocarbons.
These paraffins are used in a mixture and are preferably liquid at room temperature.
Commercially available paraffinic softeners that are liquid at room temperature include NA Solvent (isoparaffinic hydrocarbon oil) manufactured by Nippon Oil & Fats, PW-90 (n-paraffinic process oil) manufactured by Idemitsu Kosan Co., Ltd., and Idemitsu. Examples thereof include IP-solvent 2835 (synthetic isoparaffinic hydrocarbon, 99.8% by mass or more isoparaffin) manufactured by Petrochemical Co., Ltd., neothiozole (n-paraffinic process oil) manufactured by Sanko Chemical Co., Ltd., and the like.

Moreover, a small amount of unsaturated hydrocarbons and derivatives thereof may coexist in the non-aromatic hydrocarbon softener.
Unsaturated hydrocarbons include ethylene, propylene, 1-butene, 2-butene, isobutylene, 1-pentene, 2-pentene, 3-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2 -Ethylene hydrocarbons such as butene, 1-hexene, 2,3-dimethyl-2-butene, 1-heptene, 1-octene, 1-nonene, 1-decene, acetylene, methylacetylene, 1-butyne, 2- Examples thereof include acetylene hydrocarbons such as butyne, 1-pentyne, 1-hexyne, 1-octyne, 1-nonine and 1-decyne.

  Examples of the synthetic resin softener include polybutene and low molecular weight polybutadiene.

The softening agent (V) mentioned above can be arbitrarily added at a ratio of 1 to 300 parts by mass with respect to (I) + (II) = 100 parts by mass.
In order to obtain a composition excellent in flexibility and physical property balance, 50 to 250 parts by mass is more preferable, and 100 to 200 parts by mass is more preferable.
When it is less than 1 part by mass, the flexibility of the crosslinked composition is insufficient, and when it exceeds 300 parts by mass, the bleed-out of the softening agent and the mechanical properties of the crosslinked composition and the molded product tend to be lowered.

[Other additives]
An arbitrary hardness adjusting agent can be blended in the crosslinked composition of the present embodiment as necessary.
The hardness adjusting agent is not particularly limited as long as it is a conventionally known one generally used for blending a thermoplastic elastomer composition.
Examples of the hardness adjuster include castor oil and derivatives thereof (fatty acids, esters, modified polyols, sulfated oils / salts, dehydrates, etc.), terpene oils, terpene hydrocarbons having 10 carbon atoms, Terpene ether, etc., petroleum resins; resins obtained by copolymerizing unsaturated hydrocarbons obtained in various processes in the petroleum refining industry and petrochemical industry, particularly in the decomposition process of naphtha, and starting from C5 fraction Aliphatic petroleum resin, aromatic petroleum resin made from C9 fraction, alicyclic petroleum resin made from dicyclopentadiene, terpene resin, and copolymerization of these two or more types Based petroleum resins, hydrogenated petroleum resins obtained by hydrogenating these, and the like. These may be used alone or in combination of two or more.

Moreover, arbitrary filler and a flame retardant can be mix | blended with the crosslinked composition of this embodiment as needed.
The filler and the flame retardant are not particularly limited as long as they are materials generally used for blending polar resins and rubber-like polymers.
Examples of the filler include silica, calcium carbonate, magnesium carbonate, magnesium hydroxide, aluminum hydroxide, calcium sulfate, barium sulfate, carbon black, glass fiber, glass beads, glass balloon, glass flake, graphite, titanium oxide, and titanium. Potassium acid whisker, carbon fiber, alumina, kaolin clay, silicic acid, calcium silicate, quartz, mica, talc, clay, zirconia, potassium titanate, alumina, metal particles and other inorganic fillers, wooden chips, wooden powder, pulp And organic fillers such as
The shape of the filler is not particularly limited, such as scaly, spherical, granular, powder, and indefinite shape.
These may be used alone or in combination.

Examples of the flame retardant include phosphorus-based compounds such as halogen-based, phosphorus-based aromatic compounds and phosphate ester-based compounds containing bromine and the like, and flame retardants such as metal hydroxides. A flame retardant is preferred.
Examples of the inorganic flame retardant include metal hydroxides such as magnesium hydroxide, aluminum hydroxide and calcium hydroxide, metal oxides such as zinc borate and barium borate, other calcium carbonate, clay, basic magnesium carbonate, hydrotalc. Examples of the site include mainly hydrous metal compounds.
In the present embodiment, among the above flame retardants, metal hydroxides such as magnesium hydroxide and phosphorus compound flame retardants are preferable from the viewpoint of improving flame retardancy.
In addition, although the flame retardancy expression effect itself is low, a flame retardant system that exhibits a synergistically superior effect when used in combination with other compounds may be used. You may use it in combination with an adjuvant.

As the filler and flame retardant described above, a surface treatment agent such as a silane coupling agent, which has been surface-treated in advance, may be used.
These fillers and flame retardants may be used in combination of two or more as required.
When using together, it is not a thing specifically limited, The combination of a filler component or a flame retardant component or a filler and a flame retardant may be sufficient.

  If necessary, other additives described in “Rubber / Plastic Compounding Chemicals” (edited by Rubber Digest Co., Ltd.) or a mixture thereof may be added to the crosslinked composition of this embodiment.

[Method for producing crosslinked composition]
The method for producing the crosslinked composition of the present embodiment comprises:
(I) vinyl aromatic copolymer rubber containing 5-70% by mass of vinyl aromatic monomer unit and 0.1-30% by mass of conjugated diene monomer unit: 1-99 parts by mass,
(II) ethylene copolymer rubber: 99 to 1 part by mass;
For (I) + (II) = 100 parts by mass,
(III) Olefin resin: 10 to 100 parts by mass;
(IV) Crosslinking agent: 0.01 to 50 parts by mass;
Are mixed and dynamically crosslinked under melt conditions.

The method for dynamic crosslinking is not particularly limited, and a conventionally known method can be used.
Dynamic crosslinking means crosslinking treatment in a dynamic state such as melt-kneading and expresses a unique dispersion that is not seen in the case of non-dynamic crosslinking treatment. It is advantageous for the development of thermoplasticity.
As an apparatus used for dynamic crosslinking, any melt kneader capable of uniformly mixing the components can be used, and examples thereof include a single screw extruder, a twin screw extruder, a kneader, and a Banbury mixer.
In particular, it is preferable to use a twin screw extruder having a large shearing force during kneading and capable of continuous operation.
“Melting and kneading” means mixing in a state where the composition is melted at a temperature equal to or higher than the melting point of the composition. A preferable temperature is 100 to 300 ° C., and more preferably 150 to 250 ° C.

[Molded body]
Various molded bodies can be obtained by molding the crosslinked composition of the present embodiment.
As the molding method, extrusion molding, injection molding, hollow molding, pressure molding, vacuum molding, foam molding, multilayer extrusion molding, multilayer injection molding, high frequency fusion molding, slush molding, calendar molding, and the like can be applied.
In addition, the surface of the molded body can be subjected to decoration such as printing, painting, embossing and the like for the purpose of improving the appearance, weather resistance, scratch resistance and the like as necessary. When surface treatment is performed for the purpose of improving printability, paintability, etc., the surface treatment method is not particularly limited, and physical methods, chemical methods, etc. can be used. For example, corona discharge treatment, ozone Treatment, plasma treatment, flame treatment, acid / alkali treatment, and the like. Among these, corona discharge treatment is preferable from the viewpoints of ease of implementation, cost, continuous treatment, etc.

[Use]
The crosslinking composition of this embodiment can be used for various applications by blending various additives as desired.
For example, (i) reinforcing filler formulation, (ii) cross-linked product, (iii) foam, (i
v) multilayer films and sheets, (v) building materials, (vi) vibration damping and soundproofing materials, (vii)
) Wire covering material, (viii) high frequency fusible composition, (ix) slush molding material,
(X) an adhesive composition, (xi) an asphalt composition, (xii) a medical device material, (x
iii) It can be suitably used for automobile materials and the like.
Examples of the molded body include sheets, films, tubes, nonwoven fabrics and fibrous molded bodies, synthetic leather, and the like. Specifically, food packaging materials, medical device materials, home appliances and parts thereof, It can be used for electronic devices and parts thereof, automobile parts, industrial parts, household goods, materials such as toys, footwear materials, textile materials, adhesive / adhesive materials, asphalt modifiers, and the like.
Specific examples of automotive parts include side moldings, grommets, knobs, weatherstrips, window frames and their sealing materials, armrests, door grips, handle grips, console boxes, bed rests, instrument panels, bumpers, spoilers, airbag devices Storage cover and the like.
Specific examples of the medical device include a blood bag, a platelet storage bag, an infusion (medical solution) bag, an artificial dialysis bag, a medical tube, and a catheter.
In addition, industrial or food hoses, vacuum cleaner hoses, electric cooling packings, electric wires, other various coating materials, grip coating materials, soft dolls, etc., adhesive tapes, sheets, film substrates, surface protection film substrates And adhesives for films, adhesives for carpets, stretch packaging films, heat-shrinkable films, coating materials for coated steel pipes, sealants and the like.

Hereinafter, the present invention will be described with reference to specific examples and comparative examples.
The physical property measurement method and evaluation method applied to the examples and comparative examples are shown below.

[I. (I) Composition and Structural Evaluation of Vinyl Aromatic Copolymer Rubber]
(I-1) (I) Styrene content of vinyl aromatic copolymer rubber Using a non-hydrogenated vinyl aromatic block copolymer ((I) before hydrogenation), an ultraviolet spectrophotometer (Shimadzu) Measurement was performed using a UV-2450) manufactured by Seisakusho.

(I-2) (I) Polystyrene block content of vinyl aromatic copolymer rubber A non-hydrogenated vinyl aromatic block copolymer ((I) before hydrogenation) was used. M. Kolthoff, etal. , J .; Polym. Sci. 1,429 (1946), and measured by the osmium tetroxide decomposition method.
An osmic acid 0.1 g / 125 mL tertiary butanol solution was used for the decomposition of the copolymer.

(I-3) (I) Vinyl bond amount of vinyl aromatic copolymer rubber Using a non-hydrogenated vinyl aromatic block copolymer ((I) before hydrogenation), an infrared spectrophotometer ( It was measured using JASCO Corporation FT / IR-230).
The vinyl bond content of the block copolymer was calculated by the Hampton method.

(I-4) (I) Molecular weight and molecular weight distribution of vinyl aromatic copolymer rubber GPC [Apparatus: Tosoh HLC-8220, Column: TSKgel SuperH-RC × 2] was measured.
Tetrahydrofuran was used as the solvent.
Measurement conditions were performed at a temperature of 35 ° C.
Using a calibration curve prepared using a commercially available standard polystyrene having a known weight average molecular weight and number average molecular weight, the weight average molecular weight in terms of polystyrene was determined.
The molecular weight distribution is a ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn).

(I-5) (I) Hydrogenation rate of double bond of conjugated diene monomer unit in vinyl aromatic copolymer rubber and isoprene content Nuclear magnetism using hydrogenated block copolymer after hydrogenation Measurement was performed with a resonance device (device name: DPX-400; manufactured by BRUKER, Germany).

[II. Characteristics of cross-linked composition
(II-1) Hardness: Measured according to JIS K 7215.
In addition, the test piece measured by durometer hardness and type A using the 6.3 mm thickness press sheet.
When the Shore A hardness was in the range of 50 to 70, it was judged that the product had sufficient practical flexibility.

(II-2) Tensile stress, tensile strength, elongation at break In accordance with JIS K6251, a tensile test was carried out with a No. 3 dumbbell and a crosshead speed of 500 mm / min.
Tensile stress (100% Mo): Stress at 100% elongation was measured.
Tensile strength (Tb): The stress at break was measured.
Elongation at break (Eb): The elongation at break was measured.

(II-3) Heat resistance A compression set test was performed in accordance with JIS K6262.
The measurement conditions were a temperature of 120 ° C. and 22 hours.
The compression set was judged to be good if it was 35% or less.

(II-4) Molding processability Extrudability: A sheet having a width of 50 mm and a thickness of 1 mm was extruded, and the poorly melted defects, drawdown property, surface appearance and shape were observed and comprehensively judged.
○: Good: No particular problem.
Δ: Slightly bad: Intermediate level between ○ and ×.
×: Poor: Level that clearly needs improvement.

Next, each component used in Examples and Comparative Examples is shown below.
<Preparation of hydrogenation catalyst>
The hydrogenation catalyst used for the hydrogenation reaction of the block copolymer was prepared by the following method.
Charge 1 liter of dry and purified cyclohexane to a nitrogen-substituted reaction vessel, add 100 mmol of biscyclopentadienyltitanium dichloride, add an n-hexane solution containing 200 mmol of trimethylaluminum with sufficient stirring, and For about 3 days.

[(I) Preparation of vinyl aromatic copolymer rubber]
<Polymer A> Hydrogenated Isoprene-Styrene-Butadiene-Styrene-Isoprene Batch polymerization was performed by washing, drying, and purging nitrogen with a stirring device having an internal volume of 10 L and a jacketed tank reactor.
First, after adding a cyclohexane solution containing 1.5 parts by mass of isoprene, 0.05 parts by mass of n-butyllithium with respect to 100 parts by mass of all monomers and tetramethylethylenediamine (TMEDA) with respect to 1 mol of n-butyllithium. 0.55 mol was added and polymerized at 70 ° C. for 30 minutes.
Thereafter, a cyclohexane solution containing 15 parts by mass of styrene was added and polymerized at 70 ° C. for 30 minutes.
Next, a cyclohexane solution containing 67 parts by mass of butadiene was added and polymerized at 70 ° C. for 1 hour.
Next, a cyclohexane solution containing 15 parts by mass of styrene was added and polymerized at 70 ° C. for 30 minutes.
Finally, a cyclohexane solution containing 1.5 parts by mass of isoprene was charged and polymerized at 70 ° C. for 30 minutes.
The obtained polymer had a styrene content of 30% by mass, a polystyrene block content of 29.7% by mass, an isoprene content of 3% by mass, a vinyl bond content of the polybutadiene block part of 35% by mass, a molecular weight of the whole polymer of 192,000, The molecular weight of the polystyrene block was 58,000 and the molecular weight distribution was 1.04.
Next, 100 ppm of the hydrogenation catalyst as titanium per 100 parts by mass of the polymer was added to the obtained polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.7 MPa and a temperature of 65 ° C.
Thereafter, methanol was added, and then 0.3 parts by mass of octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer.
The hydrogenated block copolymer (Polymer A) thus obtained had a hydrogenation rate of 100% for butadiene and 4% for isoprene.

<Polymer B> Hydrogenated Styrene-Isoprene-Butadiene-Isoprene-Styrene A batch apparatus was prepared by washing, drying, and purging nitrogen with a stirring device having an internal volume of 10 L and a jacketed tank reactor.
First, after adding a cyclohexane solution containing 15 parts by mass of styrene, 0.05 parts by mass of n-butyllithium with respect to 100 parts by mass of all monomers and 0% of tetramethylethylenediamine (TMEDA) with respect to 1 mol of n-butyllithium. .55 mol was added and polymerized at 70 ° C. for 30 minutes.
Thereafter, a cyclohexane solution containing 1.5 parts by mass of isoprene was added and polymerized at 70 ° C. for 30 minutes.
Next, a cyclohexane solution containing 67 parts by mass of butadiene was added and polymerized at 70 ° C. for 1 hour.
Next, a cyclohexane solution containing 1.5 parts by mass of isoprene was added and polymerized at 70 ° C. for 30 minutes. Finally, a cyclohexane solution containing 15 parts by mass of styrene was charged and polymerized at 70 ° C. for 30 minutes.
The obtained polymer had a styrene content of 30% by mass, a polystyrene block content of 29.8% by mass, an isoprene content of 3% by mass, a vinyl bond content of 35% by mass of the polybutadiene block part, a molecular weight of the whole polymer of 193,000, The molecular weight of the polystyrene block was 58,000 and the molecular weight distribution was 1.04.
Next, 100 ppm of the hydrogenation catalyst as titanium per 100 parts by mass of the polymer was added to the obtained polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.7 MPa and a temperature of 65 ° C.
Thereafter, methanol was added, and then 0.3 parts by mass of octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer.
The resulting hydrogenated block copolymer (Polymer B) had a hydrogenation rate of 100% for butadiene and 5% for isoprene.

<Polymer C> Hydrogenated product of styrene-butadiene-styrene Batch polymerization was carried out by washing, drying, and purging nitrogen with a stirrer having an internal volume of 10 L and a jacketed tank reactor.
First, after adding a cyclohexane solution containing 15 parts by mass of styrene, 0.05 parts by mass of n-butyllithium with respect to 100 parts by mass of all monomers and 0% of tetramethylethylenediamine (TMEDA) with respect to 1 mol of n-butyllithium. .55 mol was added and polymerized at 70 ° C. for 30 minutes.
Thereafter, a cyclohexane solution containing 70 parts by mass of butadiene was added and polymerized at 70 ° C. for 30 minutes.
Finally, a cyclohexane solution containing 15 parts by mass of styrene was added and polymerized at 70 ° C. for 30 minutes.
The obtained polymer had a styrene content of 30% by mass, a polystyrene block content of 29.7% by mass, a vinyl bond content of the polybutadiene block part of 35% by mass, a molecular weight of the whole polymer of 1890,000, and a molecular weight of polystyrene block of 5.7. The molecular weight distribution was 1.04.
Next, 100 ppm of the hydrogenation catalyst as titanium per 100 parts by mass of the polymer was added to the obtained polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.7 MPa and a temperature of 65 ° C.
Thereafter, methanol was added, and then 0.3 parts by mass of octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer. The resulting hydrogenated block copolymer (Polymer C) had a butadiene hydrogenation rate of 80%.

<Polymer D> Hydrogenated product of styrene-butadiene-styrene Batch polymerization was carried out by washing, drying, and purging nitrogen with a stirring apparatus having an internal volume of 10 L and a jacketed tank reactor.
First, after adding a cyclohexane solution containing 15 parts by mass of styrene, 0.05 parts by mass of n-butyllithium with respect to 100 parts by mass of all monomers and tetramethylethylenediamine (TMEDA) with respect to 1 mol of n-butyllithium. 0.55 mol was added and polymerized at 70 ° C. for 30 minutes.
Thereafter, a cyclohexane solution containing 70 parts by mass of butadiene was added and polymerized at 70 ° C. for 30 minutes.
Finally, a cyclohexane solution containing 15 parts by mass of styrene was added and polymerized at 70 ° C. for 30 minutes.
The obtained polymer had a styrene content of 30% by mass, a polystyrene block content of 29.7% by mass, a vinyl bond content of the polybutadiene block part of 35% by mass, a molecular weight of the whole polymer of 1890,000, and a molecular weight of polystyrene block of 5.7. The molecular weight distribution was 1.04.
Next, 100 ppm of the hydrogenation catalyst as titanium per 100 parts by mass of the polymer was added to the obtained polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.7 MPa and a temperature of 65 ° C.
Thereafter, methanol was added, and then 0.3 parts by mass of octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer.
The hydrogenated block copolymer (Polymer D) obtained had a butadiene hydrogenation rate of 100%. No butadiene remained in the polymer, and the content of the conjugated diene monomer unit was 0% by mass.

<Polymer E> Hydrogenated product of styrene-butadiene-styrene Batch polymerization was carried out by washing, drying, and purging nitrogen with a stirring apparatus having an internal volume of 10 L and a jacketed tank reactor.
First, after adding a cyclohexane solution containing 15 parts by mass of styrene, 0.05 parts by mass of n-butyllithium with respect to 100 parts by mass of all monomers and tetramethylethylenediamine (TMEDA) with respect to 1 mol of n-butyllithium. 0.55 mol was added and polymerized at 70 ° C. for 30 minutes.
Thereafter, a cyclohexane solution containing 70 parts by mass of butadiene was added and polymerized at 70 ° C. for 30 minutes.
Finally, a cyclohexane solution containing 15 parts by mass of styrene was added and polymerized at 70 ° C. for 30 minutes.
The obtained polymer had a styrene content of 30% by mass, a polystyrene block content of 29.7% by mass, a vinyl bond content of the polybutadiene block part of 35% by mass, a molecular weight of the whole polymer of 192,000, and a molecular weight of the polystyrene block of 5.7. The molecular weight distribution was 1.04.
Next, 100 ppm of the hydrogenation catalyst as titanium per 100 parts by mass of the polymer was added to the obtained polymer, and a hydrogenation reaction was performed at a hydrogen pressure of 0.7 MPa and a temperature of 65 ° C.
Thereafter, methanol was added, and then 0.3 parts by mass of octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate as a stabilizer was added to 100 parts by mass of the polymer.
The obtained hydrogenated block copolymer (Polymer E) had a butadiene hydrogenation rate of 50%, and the residual butadiene content was 35% by mass of the copolymer.

<Polymer F> Styrene-butadiene-styrene Batch polymerization was carried out by washing, drying, and purging nitrogen with a stirring apparatus and jacketed tank reactor having an internal volume of 10 L.
First, after adding a cyclohexane solution containing 40 parts by mass of styrene, 0.05 parts by mass of n-butyllithium with respect to 100 parts by mass of all monomers and tetramethylethylenediamine (TMEDA) with respect to 1 mol of n-butyllithium. 0.55 mol was added and polymerized at 70 ° C. for 30 minutes.
Thereafter, a cyclohexane solution containing 20 parts by mass of butadiene was added and polymerized at 70 ° C. for 30 minutes.
Finally, a cyclohexane solution containing 40 parts by mass of styrene was added and polymerized at 70 ° C. for 30 minutes.
The obtained polymer had a styrene content of 80% by mass, a polystyrene block content of 79.8% by mass, a vinyl bond content of the polybutadiene block part of 35% by mass, a molecular weight of the entire polymer of 188,000, and a molecular weight of polystyrene block of 5.7. The molecular weight distribution was 1.03.

[(II) Ethylene copolymer rubber]
EPDM product name: Nordel IP 4770R (Dow Chemical Co.).

[(III) Olefin resin]
Polypropylene resin Trade name: PL500A (manufactured by Sun Allomer), MFR (230 ° C., 2.16 kg); 3.3 g / min.

[(IV) Crosslinking agent]
Polymethylol phenolic resin Product name: Tactrol 250-I (manufactured by Taoka Chemical Co., Ltd.).

[(V) Crosslinking aid]
Zinc oxide (Wako Pure Chemical Industries, Ltd.)

[(IV) Rubber softener]
Paraffin oil Product name: PW-380 (made by Idemitsu Kosan Co., Ltd.)

[Examples 1 to 3], [Comparative Examples 1 to 8]
Each component described above is melt kneaded at a cylinder temperature of 210 ° C. and a screw rotation speed of 250 rpm using a twin-screw extruder (manufactured by Toyo Seiki Co., Ltd.) according to the component ratio shown in Table 1 to produce a crosslinked composition. did.
Table 1 shows the results of measuring the physical properties of the obtained crosslinked composition.

  As shown in Table 1, the crosslinked compositions of Examples 1 to 3 were excellent in flexibility, mechanical strength, and heat resistance, and also showed good results for molding processability.

  The crosslinked composition of the present invention comprises a reinforcing filler compound, a crosslinked product, a foam, a multilayer film and a multilayer sheet material, a building material, a vibration damping / soundproof material, a wire coating material, a high frequency fusion composition, a slash It has industrial applicability as a molding material, an adhesive composition, an asphalt composition, a medical device material, an automobile material, etc., and the molded body is a sheet, a film, a tube, a nonwoven fabric or a fibrous molded body. , Synthetic leather, food packaging materials, medical device materials, household electrical appliances and parts thereof, electronic devices and parts thereof, automotive parts, industrial parts, household goods, materials such as toys, footwear materials, textile materials, and adhesives As a material and asphalt modifier, it has industrial applicability.

Claims (8)

(I) vinyl aromatic copolymer rubber containing 5-70% by mass of vinyl aromatic monomer unit and 0.1-30% by mass of conjugated diene monomer unit: 1-99 parts by mass,
(II) ethylene copolymer rubber: 99 to 1 part by mass;
Containing,
Total amount of the (I) vinyl aromatic copolymer rubber and the (II) ethylene copolymer rubber: 100 parts by mass,
(III) Olefin resin: 10 to 100 parts by mass;
(IV) Crosslinking agent: 0.01 to 50 parts by mass;
Is a crosslinked composition obtained by crosslinking a composition containing   The crosslinked composition according to claim 1, wherein the (I) vinyl aromatic copolymer rubber has a conjugated diene monomer block at a terminal portion.   2. The vinyl aromatic block copolymer (I) is a hydrogenated vinyl aromatic block copolymer comprising a vinyl aromatic monomer unit and a conjugated diene monomer unit. Cross-linking composition.   (V) The rubber softener is a total amount of the (I) vinyl aromatic copolymer rubber and the (II) ethylene copolymer rubber: 1 to 300 parts by mass with respect to 100 parts by mass, Furthermore, the crosslinked composition as described in any one of Claims 1 thru | or 3 contained.   The crosslinked composition according to any one of claims 1 to 4, wherein the (II) ethylene copolymer rubber is an ethylene-propylene-nonconjugated diene copolymer rubber (EPDM).   The crosslinked composition according to any one of claims 1 to 5, wherein the (III) olefin-based resin is polypropylene. (I) vinyl aromatic copolymer rubber containing 5-70% by mass of vinyl aromatic monomer unit and 0.1-30% by mass of conjugated diene monomer unit: 1-99 parts by mass,
(II) ethylene copolymer rubber: 99 to 1 part by mass;
Total amount of the (I) vinyl aromatic copolymer rubber and the (II) ethylene copolymer rubber: 100 parts by mass,
(III) Olefin resin: 10 to 100 parts by mass;
(IV) Crosslinking agent: 0.01 to 50 parts by mass;
A method for producing a crosslinked composition comprising the steps of mixing and dynamically crosslinking under melting conditions.   The molded object which shape | molded the crosslinked composition as described in any one of Claims 1 thru | or 6.