JPH0940824A - Thermoplastic elastomer composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a thermoplastic elastomer composition excellent in flexibility and fluidity without impairing its mechanical strength and elastic recovery, comprising each specific copolymer rubber, crystalline α-olefin polymer, hydrogenated conjugated diene copolymer and mineral oil-based softening agent in a specified proportion. SOLUTION: This thermoplastic elastomer composition comprises a total of 100 pts.wt. of (A) 10-90wt.% of a copolymer rubber chiefly made from ethylene and propylene, (B) 1-80wt.% of a hydrogenated conjugated diene copolymer or functional modified product, (C) 3-80wt.% of a crystalline >=3C α-olefin polymer chiefly made from an α-olefin such as propylene and (D) 5-80wt.% of a copolymer rubber chiefly made from ethylene and >=4C α-olefin such as butene-1 and (E) 0-200 pts.wt. of a mineral oil-based softening agent such as naphthene oil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic elastomer composition, a copolymer rubber containing ethylene and propylene as main components, and a crystalline α-olefin copolymer containing mainly α-olefin having 3 or more carbon atoms. By adding a copolymer rubber containing ethylene and an α-olefin having 4 or more carbon atoms as main components and a hydrogenated diene copolymer having a specific structure to the polymer, it has high strength and is highly flexible. A thermoplastic elastomer composition is provided.

2. Description of the Related Art Soft PVC is a material having a good balance of mechanical strength and flexibility and excellent cost performance, but its use is restricted from the viewpoint of the global environment,
Some of these are being replaced with olefinic thermoplastic elastomers. Conventionally, an olefin-based thermoplastic elastomer composition has been obtained by dynamically curing a rubber portion by a known method. By this method,
Cold resistance, weather resistance of EPM and / or EPDM,
It is possible to obtain a thermoplastic elastomer composition having excellent mechanical strength without impairing chemical resistance. However, there are problems such as odor and discoloration due to the crosslinking agent or the crosslinking aid when dynamically curing. On the other hand, sufficient mechanical strength cannot be obtained unless dynamic hardening is performed. Further, the olefin-based thermoplastic elastomer is generally poor in flexibility and is said to lack "rubber-likeness". For this reason, it has been attempted to add flexibility by blending a mineral oil-based softening agent, but the addition of a large amount of softening agent causes problems such as deterioration of physical properties such as mechanical strength and elution of the softening agent. Therefore, there are restrictions on hiring.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and provides a thermoplastic elastomer composition having flexibility and fluidity and exhibiting sufficient mechanical strength. The purpose is to

[0002]

According to the present invention, (a) 10 to 90% by weight of a copolymer rubber containing ethylene and propylene as main components, and (b) a hydrogenated conjugated diene copolymer or a functionally modified product is used. To 80% by weight, (c) 3 to 80% by weight of a crystalline α-olefin polymer mainly composed of α-olefin having 3 or more carbon atoms, (d) ethylene and α- having 4 or more carbon atoms.
Copolymer rubber containing olefin as the main component is 5 to 80% by weight.
[However, (a) + (b) + (c) + (d) = 100 wt%] (e) The mineral oil softener is 0 to 200 relative to the component (a)
It is intended to provide a thermoplastic elastomer composition comprising parts by weight.

Component (a), a copolymer rubber containing ethylene and propylene as main components, includes amorphous elastic copolymers such as ethylene / propylene copolymer rubber and ethylene / propylene / non-conjugated diene terpolymer rubber. A polymer is used. Examples of the non-conjugated diene include 1,4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 1,7-octadiene, 1,9-decadiene, 3,
6-dimethyl-1,7-octadiene, 4,5-dimethyl-1,7-octadiene, 5-methyl-1,8-nonadiene, dicyclopentadiene, 5-ethylidene-2-
Norbornene, 5-vinyl-2-norbornene, 2,5
-Norbornadiene and the like, especially 1,4
-Hexadiene, dicyclopentadiene, 5-ethylidene-2-norbornene are preferred. These ethylene
In the propylene-based copolymer rubber, the content of ethylene units per the total amount of ethylene units and propylene units is
It is usually 50 mol% or more and less than 90 mol%, preferably 60 mol% or more and less than 90 mol%. In this case, the content of ethylene units is less than 50 mol% and the content of propylene is 5
If it exceeds 0 mol%, the mechanical strength of the copolymer rubber tends to decrease, and the content of ethylene units is 90 mol%.
As described above, when the content of propylene is 10 mol% or less,
The flexibility of the copolymer rubber is lowered, which is not preferable.
In the case of ethylene / propylene / non-conjugated diene copolymer rubber, the content of the non-conjugated diene is preferably 40 or less in iodine value, more preferably 5 to 30, particularly preferably 7 to 20. These copolymer rubbers have a Mooney viscosity ML _{1 + 4} of ₁₀₀ ° C. (hereinafter abbreviated as “Moonie viscosity”) of usually 10 to 500, preferably 30 to 400. Further, when the Mooney viscosity is less than 10, the mechanical strength of the elastomer composition tends to decrease, and when it exceeds 500, poor dispersion with a crystalline polymer or the like having an α-olefin having 3 or more carbon atoms as a main component. The preferred hardness of the component (a) is 7 according to JIS-A type hardness tester.
0 or less. When the hardness exceeds 70, the flexibility of the obtained thermoplastic elastomer composition is insufficient, which is not preferable. The method for polymerizing the component (a) is not particularly limited, but the polymerization is performed in the presence of a known catalyst such as a vanadium catalyst, a titanium catalyst, a metallocene catalyst.

Further, a halogenated copolymer rubber in which a part of hydrogen atoms of the ethylene-propylene copolymer rubber is replaced by a halogen atom such as a chlorine atom or a bromine atom: or an ethylene-propylene copolymer rubber, a halogenated copolymer rubber. For polymer rubber, vinyl chloride, vinyl acetate, (meth) acrylic acid or its derivatives (for example, methyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylamide, etc.), maleic acid or its derivatives (for example, maleic anhydride) Graft copolymers obtained by graft-polymerizing unsaturated monomers such as acids, maleimides, dimethyl maleate, etc.) and conjugated dienes (eg, butadiene, isoprene, chloroprene, etc.) can also be used. The ethylene-propylene copolymer rubber can be used alone or in combination of two or more kinds.

(B) The hydrogenated conjugated diene-based copolymer has at least 80% of double bonds of conjugated diene units in the polymer.
Is a hydrogenated polymer. Examples of such hydrogenated conjugated diene polymers include hydrogenated products of block copolymers of vinyl aromatic compounds such as styrene / butadiene block copolymers and styrene / isoprene block copolymers and conjugated dienes; polybutadiene. , A hydrogenated product of a homopolymer of a conjugated diene such as polyisoprene; a hydrogenated product of a random copolymer of a vinyl aromatic compound and a conjugated diene, and the like. In particular, the following (b-1),
The hydrogenated conjugated diene polymer shown in (b-2) or (b-3) is preferable.

Component (B-1) The component (B-1) is composed of (A) a vinyl aromatic compound polymer block (hereinafter also referred to as "(A) block") and (B).
Conjugated diene copolymer block or vinyl aromatic compound-conjugated diene random copolymer block (hereinafter also referred to as "(B) block") and (C) vinyl aromatic compound-conjugated diene taper block in which vinyl aromatic compound is gradually increased. (Hereinafter also referred to as “(C) block”)
It is obtained by hydrogenating a block copolymer arranged as (A)-(B), (A)-(B)-(C), or (A)-(B)-(A). It is a thing.

Here, as the vinyl aromatic compound used to obtain the component (b-1), styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene and 1,1-diphenyl are used. styrene,
N, N-dimethyl-p-aminoethylstyrene, N, N
-Diethyl-p-aminoethylstyrene, vinylpyridine and the like, and styrene and α-methylstyrene are particularly preferred. Further, as the conjugated diene used to obtain the component (b-1), 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3
-Pentadiene, 2-methyl-1,3-pentadiene,
1,3-hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, chloroprene and the like can be mentioned, but hydrogenated diene-based compounds which can be industrially used and have excellent physical properties. To obtain a copolymer, 1,3
-Butadiene, isoprene and 1,3-pentadiene are preferred, and 1,3-butadiene is more preferred.
The block (A) in the component (B-1) is a polymer block containing a vinyl aromatic compound as a main component, and other possible vinyl aromatics are preferably copolymerized in an amount of 10% by weight or less, more preferably 10% by weight or less. You may.

In the hydrogenated block copolymer, the weight ratio of vinyl aromatic compound / conjugated diene constituting the block copolymer is preferably 5 to 60/95 to 40, more preferably 7 to 50/93 to. 50. When the vinyl aromatic compound content is less than 5% by weight (the conjugated diene content exceeds 95% by weight), the strength, processability and heat resistance are poor, and when the hydrogenated diene copolymer obtained is pelletized, blocking is likely to occur. Become. When the vinyl aromatic content exceeds 60% by weight (the conjugated diene content is less than 40% by weight), it becomes resin-like,
Poor impact resistance and low temperature characteristics.

The preferred amount of vinyl aromatic compound in the (A) block or (C) block is 3 based on the total amount of the monomers.
˜50% by weight, more preferably 5 to 40% by weight, most preferably 5 to 30% by weight. (A)
If the vinyl aromatic bond content of the block and the (C) block is less than 3% by weight of all monomers, heat resistance and mechanical strength are poor, and blocking occurs when the obtained hydrogenated diene copolymer is pelletized. In addition to being easy, when blended with other ingredients, the processability is poor, while 50% by weight
If it exceeds, the transparency, flexibility, processability, and low temperature properties will be poor.
The preferred content of the vinyl aromatic compound in the block (A) is at least 3% by weight, more preferably 5 to 30% by weight, based on the total amount of all the monomers constituting the component (B-1). If the content of the vinyl aromatic bond in the block (A) is less than 3% by weight based on the total amount of the monomers, mechanical strength, processability and heat resistance will be poor when blended with other components.

Further, in the hydrogenated block copolymer, the vinyl bond content in the conjugated diene portion in the block (B) is preferably 20% or more, more preferably 40% or more, most preferably 60% or more. Is. When the vinyl bond content is 20% or less, the effect of improving flexibility is not sufficiently exhibited even when blended with the resin component.

The above (A)-(B) block copolymer, (A)-(B)-(C) block copolymer, or (A)-(B)-(A) block copolymer. Is represented by the following formulas through a coupling agent residue,
It may be a block copolymer in which the polymer molecular chain is extended or branched. [(A)-(B)] n-X, [(A)-(B)-(C)] n-X [(A)-(B)-(A)] n-X (where (( A), (B) and (C) are the same as above.
Is an integer of 2 to 4, and X is a coupling agent residue. ) As the coupling agent in this case, for example, diethyl adipate, divinylbenzene, tetrachlorosilicon, butyltrichlorosilicon, tetrachlorotin, butyltrichlorotin, dimethylchlorosilicon, tetrachlorogermanium, 1,2-dibromoethane, 1, 4-chloromethylbenzene, bis (tricrosssilyl) ethane, epoxidized linseed oil, tolylene diisocyanate, 1,2,4
-Benzene triisocyanate and the like.

The content of the (A) block, (B) block and (C) block in the block copolymer is usually 3 to 50% by weight of the (A) block, preferably 4 to 4%.
0% by weight, (B) block 30 to 97% by weight, preferably 35 to 94% by weight, (C) block 0 to 50% by weight,
Preferably 2 to 40% by weight [(A) + (B) +
(C) = 100% by weight]. Also, (A) to (C)
The number average molecular weight of the block is (A) block is 0.15
10,000 to 350,000, more preferably 40,000 to 240,000, (B)
The number of blocks is 15,000 to 67.9,000, more preferably 3.
The range of 50,000 to 56.4 million, (C) block is 0 to 350,000, and more preferably 20,000 to 240,000.

The hydrogenation of the above block copolymer saturates the double bond of the conjugated diene portion of the block copolymer to give a hydrogenated diene-based copolymer (ro-1). ) Component is obtained. Here, the double bond of the conjugated diene moiety is 80% or more, preferably 90% or more.
% Or more, and more preferably 95 to 100% is required to be saturated, and if less than 80%, the thermal stability and durability of the thermoplastic elastomer composition will be poor. (Low
The number average molecular weight of component 1) is 50,000 to 700,000, preferably 100,000 to 600,000. Heat resistance of less than 50,000,
Strength, fluidity and workability deteriorate, and if it exceeds 700,000, fluidity, workability and flexibility deteriorate. Used in the present invention (low
The component 1) can be obtained, for example, by the method disclosed in JP-A-3-72512.

(B-2) Here, the vinyl aromatic compound and the conjugated diene used to obtain the component (B-2) are
It is the same as that used for obtaining the component (b-1). The preferable (D) block constituting the hydrogenated diene-based copolymer of the component (b-2) is a polymer block mainly containing an aromatic vinyl compound, and specifically, a homopolymer of an aromatic vinyl compound, Alternatively, a polymer block in which 80% by weight or more of the conjugated diene portion of the copolymer with the conjugated diene having 90% by weight or more of the aromatic vinyl compound in the block (D) is hydrogenated is preferable. When the content of the aromatic vinyl compound in the block (D) is less than 90% by weight, the strength,
The weather resistance decreases. The content of the block (D) in the component (B-2) is preferably 5 to 60% by weight, more preferably 1
0 to 55% by weight. The preferred number average molecular weight of the block (D) is 20,000 to 420,000. If it is less than 5% by weight, heat resistance and mechanical strength are poor. On the other hand, when it exceeds 60% by weight, workability and flexibility are deteriorated.

Further, the preferable content of the (E) block constituting the (b-2) hydrogenated diene copolymer is 30 to 90.
%, More preferably 35 to 80% by weight.
When the content of the (E) block is less than 30% by weight, the flexibility is lowered, while when it exceeds 90% by weight, the workability and mechanical strength are lowered. The vinyl bond content of the conjugated diene moiety before hydrogenation contained in the (E) block is preferably 25 to 9
It is 5%, more preferably 30 to 90%. In the conjugated diene block before hydrogenation to be the (E) block, for example, when the conjugated diene is butadiene, if the vinyl bond content is less than 25%, a polyethylene chain is formed when hydrogenated and the rubber property is lost. On the other hand, if it exceeds 95%, the glass transition temperature becomes high when hydrogenated, and the rubbery property is lost, which is not preferable. The number average molecular weight of the (E) block is preferably 15,000 to 630,000, more preferably 35,000 to 420,000, and the double bond of the conjugated diene portion is 80%.
The above is a hydrogenated conjugated diene polymer block.

Further, the (F) block constituting the block copolymer for obtaining the (B-2) component is a polybutadiene polymer block having a vinyl bond content of less than 25%, preferably less than 20%. When the vinyl bond content is 25% or more, the resinous property is lost when hydrogenated and the property of the thermoplastic elastomer as the block copolymer is lost. The content of the (F) block in the block copolymer is 5 to 60% by weight, preferably 5 to 50% by weight. (F) When the block content is less than 5% by weight,
The mechanical properties of the component (b-2) are inferior. On the other hand, when it exceeds 60% by weight, rubber properties are lost, which is not preferable. The preferred number average molecular weight of the (F) block is from 0.25 to 42.
It is a polymer block in which 80% or more of the double bonds in the butadiene portion of the polybutadiene block are hydrogenated.

The block copolymer constituting the component (b-2) is a polymer having at least one polymer block (D), (E) or (F) via a coupling agent residue. It may be a block copolymer which is bound to a polymer simple substance composed of a block and has a polymer molecular chain extended or branched as represented by the following formulas (1) to (4). [(D)-(E)-(F)] n-X [(D)-(E)-(F)] X [(D)-(E)] [-in formula, n is 2-4. An integer, X represents a coupling agent residue, and the coupling agent used is also (b-1).
Similar to those used in the ingredients]

The hydrogenation of the above block copolymer saturates the double bond of the conjugated diene portion of the block copolymer, resulting in a hydrogenated diene copolymer (II-2). ) Component is obtained. Here, the double bond of the conjugated diene needs to be 80% or more saturated, preferably 90% or more, and more preferably 95 to 100%. If the double bond saturation of the conjugated diene moiety is less than 80%, the thermal stability and durability of the thermoplastic elastomer composition will be poor. The number average molecular weight of the component (b-2) is 50,000 to 700,000, preferably 100,000 to 600,000. When it is less than 50,000, heat resistance, strength, fluidity and workability are deteriorated, and when it exceeds 700,000, fluidity, workability and flexibility are poor. The component (b-2) is, for example, JP-A-2-133406.
It can be obtained by the method disclosed in the publication.

Component (B-3) The hydrogenated diene-based copolymer (B-3) (hereinafter, also referred to as "(B-3) component") has (G) a vinyl bond content of 25% or less. Which is a polybutadiene polymer block (hereinafter also referred to as “(G) block”), and (H) a conjugated diene polymer block or a vinyl aromatic compound-conjugated diene copolymer block, wherein the vinyl bond content of the conjugated diene portion is Is 25 to 95% of the polymer block (hereinafter, also referred to as "(H) block") is (G)-(H).
It is obtained by hydrogenating 80% or more of the double bond portion of a linear or branched block copolymer arranged like-(G) or (G)-(H).

Here, as the vinyl aromatic compound and the conjugated diene used to obtain the component (b-3),
The compounds exemplified as those used for obtaining the component (b-1) can be mentioned. The (G) block in the component (B-3) becomes a crystalline polymer block having a structure similar to that of ordinary low density polyethylene (LDPE) by hydrogenation. The 1,2-vinyl bond content in the block (G) is usually 25% or less, but preferably 2
It is desirable to be 0% or less, and more preferably 15% or less. When the 1,2-vinyl bond content in the block (A) exceeds 25%, the crystal melting point after hydrogenation is remarkably lowered, resulting in poor mechanical strength.

The block (H) is a conjugated diene polymer block or a vinyl aromatic compound-conjugated diene copolymer block, and is a rubber-like ethylene-butene-1 copolymer block or a vinyl aromatic compound obtained by hydrogenation. It becomes a polymer block showing a structure similar to that of the compound-ethylene-butene-1 copolymer.

The vinyl aromatic compound used in the (H) block is used in an amount of 35% by weight or less, preferably 30% by weight or less of the monomers constituting the (H) block.
More preferably, it is 25% by weight or less, and if it exceeds 35% by weight, the glass transition temperature of the (H) block rises, resulting in poor low temperature characteristics and flexibility. The vinyl bond content of the conjugated diene portion of the (H) block is 25 to 95%, preferably 2
5 to 75%, more preferably 25 to 55%, 25
If it is less than 95% or more than 95%, hydrogenation results in a crystal structure derived from a polyethylene chain and a polybutene-1 chain, for example, when the conjugated diene is butadiene, resulting in a resin-like property and poor flexibility.

In the block copolymer for obtaining the component (b-3), the ratio of the (G) block to the (H) block is usually 5 to 90% by weight, preferably 10 to 50% by weight. 80% by weight, (H) block 95 to 10% by weight, preferably 90 to 20% by weight (however, (G) +
(H) = 100% by weight]. When the content of the (G) block is less than 5% by weight and the content of the (H) block exceeds 95% by weight, the crystalline polymer block is insufficient and the mechanical properties of the component (B-3) are inferior, which is not preferable. Further, when the content of the (G) block is more than 90% by weight and the content of the (H) block is less than 10% by weight, the hardness of the component (B-3) increases, which is not preferable. The weight average molecular weight of the (G) block is preferably 0.25 to 630,000, more preferably 10,000 to
It is 480,000. The weight average molecular weight of the (H) block is preferably from 5,000 to 66,000, more preferably from 20,000 to 540,000.

The block copolymer for obtaining the component (b-3) is a block copolymer composed of at least one polymer block of the (G) block and the (H) block via the coupling agent residue. It may be a block copolymer which is combined with a simple substance and has a polymer molecular chain extended or branched, for example, as represented by the following formulas. [(G)-(H)] n-X [(G)-(H)-(G)] n-X (In the formulas, n and X are the same as above) Further, the coupling agent is also the above ( (B) The same compounds as those used for the component (1) can be mentioned.

By hydrogenating the above block copolymer, the double bond of the conjugated diene portion of the block copolymer is saturated, so that the block copolymer is a hydrogenated diene copolymer (ro-3). ) Component is obtained. Here, the double bond of the conjugated diene needs to be 80% or more saturated, preferably 90% or more, and more preferably 95 to 100%. If the double bond saturation of the conjugated diene moiety is less than 80%, the thermal stability and durability of the thermoplastic elastomer will be poor. The number average molecular weight of the component (b-3) is 50,000 to 700,000, preferably 100,000 to 600,000. When it is less than 50,000, heat resistance, strength, fluidity and workability are deteriorated, and when it exceeds 700,000, fluidity, workability and flexibility are poor.
The component (B-3) can be obtained, for example, by the method disclosed in Japanese Patent Laid-Open No. 3-1289576.

Each hydrogenated diene polymer used as the component (b) in the present invention may be a modified hydrogenated block polymer modified with a functional group. The modified hydrogenated block polymer is a hydrogenated block polymer selected from the group consisting of carboxyl group, acid anhydride group, hydroxyl group, epoxy group, halogen atom, amino group, isocyanate group, sulfonyl group and sulfonate group. It can be made by containing at least one kind of functional group. As a method of containing this functional group,
Using a conjugated diene or vinyl aromatic compound containing a functional group to obtain a block copolymer by copolymerizing with the functional group of the monomer protected, and after completion of polymerization, deprotection is in progress To the hydrogenated block polymer by a known grafting reaction of a radically polymerizable monomer having a functional group, using a monomer having a functional group, an organic peroxide or an azo compound In the presence or absence of, a hydrogenated block polymer kneader,
Examples thereof include a method of adding a functional group by kneading with a mixer, an extruder or the like. By using any of these methods, the functional group can be efficiently contained, but industrially, the methods 1 to 3 above are simple and effective. The amount of the functional group in the modified hydrogenated block polymer is usually 0.01 to 10 mol%, preferably 0.1 to 8 mol% with respect to the molecules constituting the hydrogenated block polymer.
More preferably, it is 0.15 to 5 mol%. Preferred examples of the monomer that adds a functional group to the hydrogenated block polymer include acrylic acid, methacrylic acid, itaconic acid, maleic acid, maleic anhydride, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, and hydroxyethylene. Methacrylate, hydroxypropyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, dimethylaminoethyl methacrylate and the like can be mentioned.

Next, it is used in the composition of the present invention (c).
Crystalline α mainly composed of α-olefin having 3 or more carbon atoms
Examples of the main component of the olefin copolymer include polypropylene, poly 1-butene, poly 4-methyl-1-pentene, poly 1-hexene, propylene-ethylene copolymer, and propylene-1-butene copolymer. Can be mentioned. Of these, polypropylene, random or block ethylene-propylene copolymers are preferred.
The component (c) is crystalline, and specifically, it has an n-decane insoluble content of 50% by weight or more, preferably 60% by weight or more, more preferably 70% by weight or more. If the n-decane-insoluble content is less than 50% by weight, the mechanical strength and molding processability of the obtained thermoplastic elastomer composition may be impaired.

Next, the copolymer rubber (d) used in the present invention, which is mainly composed of ethylene and an α-olefin having 4 or more carbon atoms, is an ethylene / 1-butene copolymer or ethylene / propylene / 1-. Butene copolymer, ethylene / 1-hexene copolymer, ethylene / 1-octene copolymer, ethylene / propylene / 1-hexene copolymer, ethylene / propylene / 1-octene copolymer, ethylene / 1-butene・ 1-Hexene copolymer, ethylene / 1-butene / 1
-Octene copolymer, ethylene / 1-hexene / 1-octene copolymer, ethylene / 1-butene / dicyclopentadiene copolymer, ethylene / 1-butene / 5-ethylidene-2-norbornene copolymer, ethylene .1-hexene-dicyclopentadiene copolymer, ethylene-1.
Hexene-5-ethylidene-2-norbornene copolymer, ethylene / 1-octene / dicyclopentadiene copolymer, ethylene / 1-octene / 5-ethylidene-2
-Norbornene copolymer etc. can be illustrated. The method for polymerizing the component (d) is not particularly limited, but the polymerization is performed in the presence of a known catalyst such as a vanadium catalyst, a titanium catalyst, a metallocene catalyst. These ethylene-based copolymers may be a mixture of two or more kinds. The MFR of the copolymer is not particularly limited, but is preferably 0.1 to 200.
g / 10 minutes. The ethylene content of the ethylene-C4 or more α-olefin copolymer rubber as the component (d) is 9
It is preferably less than 0 mol% or the hardness is more than 70 and 93 or less as measured by the JIS-A type hardness meter. Ethylene content exceeds 90 mol% or hardness is 9
When it is 3 or more, flexibility of the copolymer rubber is insufficient, which is not preferable. Further, if the hardness is 70 or less, the mechanical strength of the obtained composition is insufficient, which is not preferable.

The above (a) to be used in the composition of the present invention
The blending amount of the component (c) is such that (a) the ethylene-propylene copolymer rubber exceeds 10% by weight and 90% by weight or less, preferably 30 to 80% by weight, more preferably 50 to 75% by weight. Hydrogenated diene-based copolymers with the structure
To 80% by weight, preferably 20 to 60% by weight, more preferably 30 to 60% by weight (c) 3 to 80% by weight of a crystalline α-olefin polymer mainly composed of an α-olefin having 3 or more carbon atoms. %, Preferably 20-40% by weight (d)
5 to 80% by weight, preferably 8 to 30% by weight of ethylene-α-olefin copolymer rubber having 4 or more carbon atoms [(A) + (B) + (C) + (D) = 100% by weight] ]
It is. Here, when the compounding amount of the (a) olefin-based copolymer rubber is 10% by weight or less, the rubber elasticity and flexibility of the obtained composition are deteriorated. On the other hand, when the amount of component (a) exceeds 90% by weight, the moldability and mechanical strength of the resulting composition deteriorate. Further, when the content of the component (C) is 3% by weight or less, the heat resistance of the obtained composition deteriorates. Further, when the content of the component (d) is 5% by weight or less, the mechanical strength of the obtained composition decreases.

As the component (e) component mineral oil plasticizer used in the present invention, naphthene oil or paraffin mineral oil can be used. Such oil extension further improves processability and flexibility. In this case, the oil extension amount is 0 to 200 weight, preferably 0 to 1 per olefin copolymer rubber.
The amount is 00 parts by weight, more preferably 0 to 50 parts by weight.

The thermoplastic elastomer composition of the present invention may be produced by any method as long as good dispersion of each component can be obtained, and is not particularly limited. Usually, the target polymer is melt-kneaded by a roll mill, a Banbury mixer, a closed kneader such as a pressure kneader, or a single-screw extruder or a twin-screw extruder used in the rubber / resin industry. In the production of the composition of the present invention, the mixing temperature (kneading temperature) is at least (b),
It is the temperature at which the components (C) and (D) are melted, and is usually in the range of 120 to 280 ° C.

The thermoplastic elastomer composition of the present invention has a mechanical strength and flexibility in addition to the above-mentioned components (a), (b), (c) and (d), depending on the application. Antioxidant, antistatic agent, weatherproofing agent, UV absorber, lubricant, antiblocking agent, sealability improving agent, crystal nucleating agent, flame retardant, antibacterial and antifungal agent in an amount that does not impair moldability. , Tackifiers, softeners, plasticizers, colorants such as titanium oxide and carbon black, glass fibers, carbon fibers, metal fibers, aramid fibers, glass beads, asbestos, mica, calcium carbonate, potassium titanate whiskers, talc, Fillers such as barium sulfate, glass flakes and fluororesins, plasticizers such as naphthene oil and paraffin mineral oil, rubber polymers such as isobutylene-isoprene copolymer, thermoplastics Can be blended fat, etc. as appropriate.

The thermoplastic elastomer composition of the present invention comprises:
By utilizing flexibility and molding processability without impairing mechanical strength, conventional soft vinyl chloride resin is used, interior and exterior parts of automobiles, packing of weak electric parts and It can be used for parts such as housings, industrial parts, and waterproof sheet parts.

[0034]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist. In the examples, parts and% are based on weight unless otherwise specified.
In addition, various measurements in the examples were performed by the following methods.

JIS A hardness was measured according to JIS K6301. Elastic recovery The following substitute properties and good permanent elongation were considered good. Permanent elongation: Based on JIS K6301, it was maintained under 100% elongation for 10 minutes, then the elongation was released, and it was determined from the elongation rate after standing for 10 minutes. The smaller the permanent set, the better the elastic recovery. 50% modulus (M100) tensile strength and maximum elongation Measured according to JIS K6301. Fluidity MFR was measured for fluidity under the following conditions. Temperature: 230 ℃ Load: 5kg

The polymers used in the examples and comparative examples are as follows. EP1 ethylene-propylene-ethylidene norbornene copolymer rubber (paraffin oil 70 phr oil extension)
[Nippon Synthetic Rubber, EP98A] EP2 ethylene-propylene-dicyclopentadiene copolymer rubber [Nippon Synthetic Rubber, EP75F] EP3 ethylene-propylene-ethylidene norbornene copolymer rubber [Nippon Synthetic Rubber, EP57P] EP4 ethylene-propylene copolymer Polymerized rubber [Nippon Synthetic Rubber, EP07P] PP1 propylene-ethylene block polymer [Mitsubishi Chemical,
BC5C] PP2 propylene-ethylene random polymer [manufactured by Mitsubishi Chemical,
EX6] PP3 polypropylene [MITSUBISHI CHEMICAL , FL6CK] EBM1 ethylene-1-butene copolymer [ Nippon Synthetic Rubber, E
BM2041] EBM2 ethylene-1-butene copolymer [ Nippon Synthetic Rubber, E
BM1021] EH ethylene / 1-hexene copolymer [manufactured by Exxon Chemical, EXACT2010] EO ethylene / 1-octene copolymer [manufactured by Dow Chemical,
ENGAGE EG8100] Hydrogenated Diene Copolymer A Hydrogenated block copolymer A is manufactured by Nippon Synthetic Rubber Co., Ltd. and has an AB structure (A is a polystyrene block, B is a copolymer block of styrene and butadiene). Hydrogenated double bonds in the butadiene part), the total bound styrene is 10%, the amount of styrene in the part A is 6%, and the amount of vinyl in the butadiene part before hydrogenation (1,2 bond amount) is 80%. And the total molecular weight is 30
10,000 hydrogenated block copolymers. Hydrogenated diene-based copolymer B Hydrogenated block copolymer B is manufactured by Nippon Synthetic Rubber Co., Ltd. and has a D-E-F structure (D is a polystyrene block, E
Is 1.2-polybutadiene with a high vinyl content, and F is 1.
2-polybutadiene having a low vinyl content, and E and F have a hydrogenated double bond in the butadiene part)
A hydrogenated block copolymer having a vinyl content of 39 parts, a vinyl content of 15 parts and a total molecular weight of 150,000. Hydrogenated Diene Copolymer C Hydrogenated block copolymer C is manufactured by Nippon Synthetic Rubber Co., Ltd. and has a G-H-G structure (G is 1.2-polybutadiene having a low vinyl content, and H is 1. 2-polyvinyl with a high vinyl content in which the double bonds of each butadiene part are hydrogenated), the vinyl content in the G part is 15%, the vinyl content in the H part is 35%, and the total molecular weight is 300. 1,000 hydrogenated block copolymers. PE1 low density polyethylene [Mitsubishi Chemical, LC500] PE2 ethylene-1-hexene copolymer rubber [Mitsubishi Chemical, S
F240 ] EO2 ethylene / 1-octene copolymer [manufactured by Dow Chemical,
AFFINITY FM1570] Mineral oil plasticizer Paraffin softener [PW-380 manufactured by Idemitsu Kosan] Filler calcium carbonate [Calcium Shiraishi, white luster CC]

The following were prepared as other additives. Inorganic filler; calcium carbonate, made by Fuji Talc

Examples 1 to 20 and Comparative Examples 1 to 9 Compositions were prepared according to the following procedures according to the formulations shown in Tables 1 and 2. First, bale-shaped EPDM is placed at 120 ° C
A sheet (IIR is 20 ° C.) is formed into a sheet, oil-extended as necessary, and a sheet cutter is used to form a 5 mm square pellet. Olefin copolymer rubber, hydrogenated diene copolymer having a specific structure, polypropylene resin, polyethylene resin, blended in a single screw extruder (manufactured by Nippon Placon) set at a predetermined temperature in a predetermined mixing ratio, as required Depending on the situation, continuously supply anti-corrosion, inorganic filler, butyl rubber, etc.,
A pellet was made.

The obtained pellets were formed into a sheet by a roll at 180 ° C., and finally, a sheet having a thickness of 2 mm was produced by a press molding machine and subjected to a test. For evaluation of hardness JIS A, permanent elongation and tensile strength, predetermined test pieces were punched out from the sheet with a dumbbell cutter. Furthermore, regarding the evaluation of compression set, 2 m produced by the injection molding machine was used.
Using an m-thick test piece, after punching, it was adjusted by stacking so as to have a specified size, and then subjected to a test. The results are shown in Tables 1 and 2.

As is clear from the comparison between Examples 1 to 20 and Comparative Examples 1 to 9, the composition of the present invention is excellent in the following points. INDUSTRIAL APPLICABILITY The thermoplastic elastomer composition of the present invention exhibits flexible properties without impairing mechanical strength, is excellent in elastic recovery, and has good flowability required for molding. Further, since the addition amount of the softening agent is small, there is no problem of bleeding out of these components. Since Comparative Example 1 does not contain the components (b) and (d), the mechanical strength is greatly inferior. Since Comparative Examples 2 to 4 do not contain the component (2), flexibility is imparted, but the mechanical strength is inferior to the Examples. Comparative Examples 5 and 6
Does not contain the component (b). Compared with Examples 1 to 20, mechanical strength is sufficient, but flexibility is poor, which is not preferable. Comparative Examples 7 to 9 are not preferable because the component (d) is out of the range of the present invention and the flexibility is inferior to the m Examples 1 to 20.

[0041]

According to the thermoplastic elastomer composition of the present invention, the flexibility and fluidity are excellent, and the mechanical strength and elastic recovery are also good. In addition, since a mineral oil-based softening agent is not included or only a small amount of addition is required, the problem of contamination due to elution of the softening agent does not occur, and addition of a large amount of the softening agent reduces the mechanical strength and elastic recovery. There is no problem. Therefore, it can be used for interior / exterior parts of automobiles, parts such as packing housings for light electric parts, industrial parts, waterproof sheet parts, gasket seal parts, etc. in which soft vinyl chloride resin is used.

[Table 1]

[Table 2]

Claims (1)

[Claims] 1. (a) 10 to 90% by weight of a copolymer rubber containing ethylene and propylene as main components, and (b) 1 to 80% by weight of a hydrogenated conjugated diene copolymer or a functional modified product (c).
Crystalline α mainly composed of α-olefin having 3 or more carbon atoms
-Olefin-based polymer is 3 to 80% by weight, (d) Copolymer rubber mainly composed of ethylene and α-olefin having 4 or more carbon atoms is 5 to 80% by weight (however, (a) + (b) +
(C) + (D) = 100% by weight] (E) A mineral oil-based softening agent is 0 to 200 relative to the component (A).
A thermoplastic elastomer composition comprising 1 part by weight.