JP2500391B2 - Flexible and heat resistant elastomer composition - Google Patents

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, and more particularly to a nontoxic and odorless elastomer composition which is excellent in flexibility, heat resistance, strength, transparency and moldability.

[0002]

2. Description of the Related Art Conventionally, in the fields of food packaging materials and medical devices, various compositions have been proposed and put into practical use as compositions for obtaining flexible and transparent molded products. For example, LDPE, ethylene-acrylate copolymers, ethylene-vinyl acetate copolymers, metal salts of ethylene-acrylic acid copolymers or methacrylic acid copolymers are used as flexible and transparent molded articles, but they are heat resistant. Is insufficient and softens at a temperature of 100 ° C. or less. Therefore, the obtained molded product has a drawback that it cannot be sterilized by high temperature heat.

Molded articles using a composition based on soft vinyl chloride are excellent in flexibility and transparency, and are 100
It can be sterilized at high temperature because its shape can be maintained even under high temperature of ℃ or more, and it is widely used for food packaging materials, medical instruments, etc. However, since a composition based on soft vinyl chloride usually contains a large amount of a plasticizer, the plasticizer may be eluted to cause a sanitary problem. In addition, the composition based on soft vinyl chloride has insufficient low temperature characteristics,
At temperatures below 0 ° C, the flexibility is significantly reduced.
Therefore, when it is stored in a frozen state or the like, there is a possibility that problems such as damage due to impact of the molded product may occur.

On the other hand, styrene elastomers such as styrene / butadiene block copolymers and styrene / isoprene block copolymers are excellent in flexibility, transparency and strength.
Further, although it has excellent low-temperature characteristics, it has a problem that it does not have sufficient heat resistance and is softened even at 100 ° C. or lower so that it cannot maintain its shape.

[0005] Therefore, the styrene-based elastomer - elastomer was used (hereinafter abbreviated as hydrogenated block copolymer) improved hydrogenated derivatives - relates to compositions, several proposals have been made. For example, JP-A-50-1474
No. 2, JP-A-52-65501 disclose an elastomer composition in which a hydrogenated block copolymer is blended with an olefin polymer and a hydrocarbon oil. These elastomer compositions maintain their shape even at a high temperature of about 120 ° C., have good flexibility even at a low temperature of about -40 ° C., and have excellent heat aging resistance, ozone resistance, and light resistance stability. It has the feature of being excellent.

However, since these compositions contain a large amount of hydrocarbon oil, elution of the hydrocarbon oil may be a problem in the fields of food packaging materials, medical instruments and the like. Therefore, for the purpose of solving the above problem, a composition of a hydrogenated block copolymer containing no hydrocarbon oil has been proposed. For example, JP-A-54-88950 discloses a composition of an ABA-type hydrogenated block copolymer and a polypropylene resin as a softening agent or a melt flow aid for assisting processability of polyethylene and ethylene-vinyl acetate. A composition comprising a softening agent selected from a polymer and an ethylene-propylene copolymer has been proposed.

However, since these softeners themselves do not have sufficient heat resistance, heat resistance can be obtained only in combination with a hydrogenated block copolymer having a specific structure, and the heat resistance is lowered. Therefore, the amount of the softening agent that can be used is limited, resulting in the problem that only a hard molded product can be obtained.

Further, JP-A-59-74152 proposes a composition comprising an ABA type hydrogenated block copolymer and a polypropylene resin and further comprising an ethylene-acrylate copolymer. The ethylene-acrylate copolymer itself has good heat resistance and flexibility, so that a flexible and excellent heat resistance composition can be obtained. However, when an ethylene-acrylate copolymer is used,
The odor of the ethylene-acrylate copolymer not only limits its use in the fields of food packaging materials, medical instruments, etc., but also causes problems such as whitening and moisture absorption due to hot water.

[0009]

Therefore, the problems of the above-mentioned prior art are solved, and a nontoxic and odorless elastomer composition excellent in flexibility, heat resistance, strength, transparency, and moldability is developed. What is desired is the reality. An object of the present invention is to provide a novel elastomer composition which meets the needs.

[0010]

As a result of research, the inventors of the present invention have blended the above-mentioned hydrogenated block copolymer with a polypropylene resin and further combined a specific ethylene-α-olefin copolymer. As a result, they have found the surprising fact that an elastomer composition which is excellent in flexibility, heat resistance, strength, transparency, and moldability, and which is nontoxic and odorless is obtained, and the present invention has been completed.

That is, the present invention has the general formula (a) consisting of a polymer block A containing at least two vinyl aromatic compounds as a main component and a polymer block B containing at least one conjugated diene compound as a main component.

Embedded image (BA) _n , B (AB) _n , [(A-B) _m ] _p -[B (AB) _{m '} ] _q -Z (However, A is a polymer mainly composed of vinyl aromatic compounds.
Block B is a polymer block mainly composed of a conjugated diene compound.
Lock, n is an integer from 2 to 6 and m and m ′ are from 1 to 6
In the following integers, m and m ′ may be the same or different,
p is an integer of 0 or more and 5 or less, q is an integer of 1 or more and 6 or less, p
+ Q is 2 or more and 6 or less, and Z is a functional group having 2 or more functional groups.
Represents the residue of a pulling agent. ) At least one
Having a polymer block B at one polymerization end Block co-weight
Block copolymer obtained by hydrogenating the polymer
%, (B) Propylene homopolymer and / or propylene
And C2-C8 α-olefin copolymer 5-40
% By weight, and (c) ethylene and an α-olefin having 3 to 12 carbon atoms
The density obtained by copolymerization is 0.860 to 0.910.
g / cm³, The melt index is 0.01 to 100 g /
10 min, maximum melting by differential scanning calorimetry (DSC)
Ethylene-α-olphi with a peak temperature of 100 ° C or higher
Flexible and excellent heat resistance consisting of 5-60% by weight of copolymer
And an elastomer composition.

The hydrogenated block copolymer used as the component (a) in the present invention is mainly composed of a polymer block A containing at least two vinyl aromatic compounds and at least one conjugated diene compound. A block copolymer obtained by hydrogenating a block copolymer comprising a polymer block B,

In addition , the hydrogenated block copolymer is
Conjugate diene compound as the main component at at least one polymerization end
Hydrogenation of block copolymer having polymer block B
It is obtained by doing.

The hydrogenated block copolymer is flexible,
It is possible to obtain a molded product with excellent processability and little anisotropy.
The effect is that you can do it. As a concrete example,

[0015]

Embedded image B-A-B-A, B-A-B-A-B, (B-
_{A-B) 4 Si, (} B-A-B) 3 -Si-R, (B-
A-B) _4- Sn, (B-A-B) _3- Sn-R, (B
-AB) _2- Si-R, R ', (AB), (BA)
-B) -Si-R, R ', (AB), (BAB)
_It is a hydrogenated block copolymer having a structure such as _2- Si-R (wherein R and R'are C ₁ -C ₈ alkyl groups and R and R'may be the same or different). . As used herein, the expression "predominantly" means that the corresponding monomer units are at least 50% by weight of the polymer block,
It means that it preferably accounts for 70% by weight or more.

Further, the polymer block A mainly containing these vinyl aromatic compounds and the polymer block B mainly containing these conjugated diene compounds have a distribution of the vinyl aromatic compound or the conjugated diene compound in each polymer block. It may be random or tapered (in which the monomer component increases or decreases along the molecular chain) or partially block-like or any combination thereof, and each of the polymer block A and the polymer block B is two or more. In some cases, each polymer block may have the same structure or different structures.

Generally, each polymer block A contains 4000 to
Having the same or different number average molecular weight in the range of 50,000, more preferably in the range of 5,000 to 40,000,
Have the same or different number average molecular weight. Further, each polymer block B has the same or different number average molecular weight in the range of 3,000 to 100,000, and more preferably 4
Have the same or different number average molecular weight in the range of 000 to 70,000. The block copolymer contains a vinyl aromatic compound in an amount of 10 to 50% by weight, preferably 15 to 40% by weight.

As the vinyl aromatic compound constituting the hydrogenated block copolymer, for example, one kind or two or more kinds can be selected from styrene, vinyltoluene, α-methylstyrene, p-tertiarybutylstyrene and the like. Of these, styrene is preferable.

Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3
One or more of dimethyl-1,3-butadiene and the like can be selected, and among them, butadiene, isoprene and a combination thereof are preferable. Then, the polymer block B mainly composed of the conjugated diene compound before hydrogenation
Can arbitrarily select the microstructure in the block, for example, in the polybutadiene block,
20-50% by weight of 1,2-microstructure, preferably 2
5 to 45% by weight.

As a method for producing these block copolymers, any method may be used as long as it has the above-mentioned structure. For example, Shokoku Sho 4
No. 0-23798, a block copolymer of a vinyl aromatic compound and a conjugated diene compound is polymerized in an inert organic solvent using a lithium catalyst or the like, and then JP-A-60-220147. JP 61-3
According to the method described in JP-A No. 3132 or JP-A No. 62-207303, hydrogenation is carried out in the presence of a hydrogenation catalyst in an inert organic solvent to synthesize the hydrogenated block copolymer used in the present invention. can do.

The conditions used to hydrogenate the block copolymers useful in this invention are at least 80%, preferably 90% or more, of the conjugated diene compound while 20% of the vinyl aromatic compound is hydrogenated. Less than, preferably less than 10% is hydrogenated.

The number average molecular weight of the hydrogenated block copolymer of the present invention having the above structure is 20,000 to 3
00000, preferably 25,000 to 250,000, more preferably 30,000 to 200,000, and the molecular weight distribution [ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) (Mw / Mn)] is 10 or less, preferably It is 5 or less, more preferably 2 or less. When the number average molecular weight is less than 20,000, the strength of the elastomer composition,
The heat resistance is not sufficient, and when it exceeds 300,000, the moldability of the elastomer composition deteriorates, which is not preferable.
Further, if the molecular weight distribution exceeds 10, the strength and heat resistance of the elastomer composition are not sufficient, which is not preferable.

Next, the propylene homopolymer used as the component (b) of the present invention or propylene and C2-8.
As the copolymer with α-olefin (hereinafter abbreviated as propylene resin), polypropylene synthesized using a Ziegler-Natta type catalyst by a known technique, or a random or block polypropylene copolymer is used.

Examples of the α-olefin in the copolymer include ethylene, butene-1, hexene-1, octene-1 and the like, and the ratio of these α-olefins is 30% by weight or less. . Melt flow rate (JI
SK6758, 230 ° C, value measured according to 2.16 kg load, hereinafter abbreviated as MFR) is 0.1 to 50 g /
It is used for 10 min, preferably 1-30 g / 10 min. When the MFR is less than 0.1 g / 10 min, the moldability of the elastomer composition deteriorates, which is not preferable. When the MFR exceeds 50 g / 10 min, the strength and heat resistance of the elastomer composition are not sufficient, which is not preferable.

Next, the copolymer of ethylene and α-olefin used as the component (c) of the present invention is a copolymer of ethylene and α-olefin having 3 to 12 carbon atoms (hereinafter referred to as ethylene- It is abbreviated as α-olefin copolymer). As the α-olefin having 3 to 12 carbon atoms, linear or branched one can be used. Examples of α-olefins include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1
-Octene, 1-decene and the like. It is also possible to use mixtures of these.

The proportion of ethylene in the ethylene-α-olefin copolymer is 50 to 90% by weight, preferably 55 to 50% by weight.
It is 85% by weight. The density of the ethylene-α-olefin copolymer is 0.860 to 0.910 g / cm ³ , preferably 0.870 to 0.905 g / cm ³ . When the density is less than 0.860 g / cm ³ , the strength of the elastomer composition is lowered, and the surface of the molded product becomes sticky and the appearance is deteriorated, which is not preferable. The density is 0.910g
If it exceeds / cm ³ , the flexibility is lowered, which is not preferable.

Further, the melt index of the ethylene-α-olefin copolymer (JISK6720, 190)
A value measured according to a load of 2.16 kg at ℃, hereinafter abbreviated as MI) is 0.01 to 100 g / 10 min, preferably 0.1 to 50 g / 10 min. When the MI is less than 0.01 g / 10 min, the moldability of the elastomer composition deteriorates, which is not preferable. MI is 100g
If it exceeds / 10 min, the strength and heat resistance of the elastomer composition are not sufficient, which is not preferable.

The maximum melting peak temperature of the ethylene-α-olefin copolymer by differential scanning calorimetry (DSC) is 100 ° C or higher, preferably 110 ° C or higher. Here, the maximum melting peak temperature is the maximum peak temperature of the thermogram obtained when the temperature is raised at a rate of 4 ° C./min using a differential scanning calorimeter.

In order to obtain the heat resistance of the elastomer composition of the present invention, the maximum melting peak temperature of the ethylene-α-olefin copolymer by differential scanning calorimetry (DSC) is 100 ° C or higher, preferably 110 ° C. It is necessary to be ℃ or more.

The ethylene-α-olefin copolymer component in the elastomer composition of the present invention is an elastomer
It is considered that the composition has an effect of improving heat resistance and moldability without impairing the flexibility of the composition.

The flexural rigidity (value measured according to ASTM D747) of the ethylene-α-olefin copolymer is 1200 kg / cm ² or less, preferably 1000 kg / cm ² or less. If the flexural rigidity exceeds 1200 kg / cm ² , the flexibility of the elastomer composition decreases, which is not preferable.

The ethylene-α-olefin copolymer is
It can be synthesized, for example, by copolymerizing ethylene and α-olefin in the presence of a Ziegler-type catalyst system. One of the Ziegler-type catalyst systems is an organometallic activating component (I to III of the periodic table). The group metal hydroxides or alkyl compounds) and the other consist of halogenated transition metal compounds and may optionally contain inorganic compounds such as magnesium or manganese. Suitable combinations include aluminum hydroxide and / or alkyl compounds and titanium halides.

In the present invention, the above-mentioned specific soft and heat-resistant ethylene-α-olefin copolymer is blended as a third component into a system of a hydrogenated block copolymer and a polypropylene-based resin to obtain a conventional composition. Known polyethylene,
The flexibility and heat resistance are greatly improved as compared with a composition with an ethylene-vinyl acetate copolymer, an ethylene-propylene copolymer, an ethylene-acrylate copolymer or the like.

The ethylene-α-olefin copolymers used in the present invention are Excellen VL100, Excellen VL200, Excellen VL700, Excellen VL8.
00 (made by Sumitomo Chemical Co., Ltd.) Nisseki Softlex C
9005, Nisseki Softlex C9510, Nisseki Softlex D9010, Nisseki Softlex D9510,
It can be easily obtained under the name such as Nisseki Softlex D9550 (both manufactured by Nippon Petrochemical Co., Ltd.). These ethylene-α-olefin copolymers are not limited to one kind, and two or more kinds may be used in combination.

In the present invention, the blending amount of the hydrogenated block copolymer as the component (a) is 30 to 90% by weight, preferably 4%.
It is 0 to 80% by weight, more preferably 45 to 70% by weight. Further, the blending amount of the propylene resin as the component (b) is 5 to 40% by weight, preferably 10 to 35% by weight.
The blending amount of the ethylene-α-olefin copolymer as the component (c) is 5 to 60% by weight, preferably 10 to 50% by weight.

When the content of the hydrogenated block copolymer as the component (a) is less than 30% by weight, the flexibility and strength of the elastomer composition will be deteriorated, and when it exceeds 90% by weight, the elastomer will be The heat resistance and moldability of the composition are insufficient, which is not preferable. When the amount of the propylene resin as the component (b) is less than 5% by weight, the heat resistance and moldability of the elastomer composition are insufficient, and when it exceeds 40% by weight, the flexibility and transparency of the elastomer composition are increased. However, the gas permeability is lowered, which is not preferable. In addition, the component (c) ethylene-
When the blending amount of the α-olefin copolymer is less than 5% by weight,
The flexibility and moldability of the elastomer composition become insufficient, and when it exceeds 60% by weight, the strength of the elastomer composition,
It is not preferable because the transparency is lowered.

In general, any method known in the art for blending polymer components may be used to prepare the elastomeric composition of the present invention. In order to obtain the most homogeneous blend, a method of melt kneading using various kneaders such as a mixing roll, a kneader, a Banbury mixer and an extruder which are commonly used is preferable.

Prior to melt-kneading, these blends are previously dry-blended using a mixer such as a Hensyl mixer or a tumbler, and the mixture is melt-kneaded to obtain a homogeneous elastomer composition. The composition of the present invention, in addition to the above essential essential components, depending on the application, flexibility, heat resistance, strength, moldability and safety of various plasticizers in an amount that does not impair safety, silicone oil, blocking It is also possible to contain an inhibitor, an ultraviolet absorber, a lubricant, a crystal nucleating agent, a coloring agent, an inorganic filler and the like.

The composition of the present invention can be molded in the same manner as a usual resin. That is, the sheet by the extruder,
Shaped extrudates, tubes, nets, etc. can be molded. It can also be used for injection molding and blow molding,
Various molded products, bottles, etc. can be molded.

[0040]

As described above, the composition of the present invention is particularly excellent in the balance of flexibility and heat resistance, and has various other characteristics. Therefore, it is suitable for general industrial materials, household products, etc. Although it can be used, it can be preferably used for applications such as food packaging materials and medical instruments that require high temperature sterilization by utilizing its high heat resistance and hygiene. Specific applications include lids for microwave oven containers, food packaging sheets or films, blood bags, infusion bags, artificial dialysis bags,
There are medical tubes and catheters.

[0041]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In these examples and comparative examples,
The test methods used for various evaluations are as follows.

(1) Hardness [-] ASTM D2240,
D type. A 3 mm thick injection sheet was used as the sample.

(2) Tensile strength [kg / cm ² ] and elongation [%]
According to JIS K6301, a sheet extruder was used as a sample, a sheet having a thickness of 0.5 mm was prepared under the following conditions, and the sheet was punched with a No. 3 dumbbell and used. Extruder ・ ・ ・ 40mmΦ Screw ・ ・ ・ L / D25, compression ratio 3.5 Die ・ ・ ・ Width 400mm Cylinder temperature (C1) ・ ・ ・ 180 ℃ Cylinder temperature (C2) ・ ・ ・ 190 ℃ Cylinder temperature (C3) 195 ° C. Cylinder temperature (C4) 200 ° C. Die temperature 200 ° C. (3) Flexural rigidity [Kg / cm ² ] ASTM D747, 3 mm thick injection test piece was used as a sample.

(4) Heat distortion temperature [° C.] A sample was cut out from a compression molded sheet having a thickness of 2 mm, and a thermomechanical analyzer (TM) was used.
Set to A). Load 500 on a 1 mmφ needle probe
g / cm ² was added and placed on the sample. The temperature was raised at 4 ° C./min, and the temperature at which the needle probe was 100 μm was taken as the heat distortion temperature.

(5) Total light transmittance [%] ASTM D1
003, a 2 mm thick injection sheet was used as the sample. Moreover, each compounded component has the structure of component (a-1) B-A-B-A, the amount of bound styrene is 31% by weight, the number average molecular weight is 52000, the molecular weight distribution is 1.08, and water is The 1,2-vinyl bond content of the polybutadiene part before addition is 37
% And a hydrogenation rate of 99%, a hydrogenated block copolymer having a hydrogenation rate of 99%
Synthesized by the method described in JP-A-33132 (a
-1) As a component.

Component (a-2) having the structure of B-A-B-A, the amount of bound styrene is 20% by weight, the number average molecular weight is 102,000, the molecular weight distribution is 1.09,
The amount of 1,2-vinyl bonds in the polybutadiene portion before hydrogenation is 3
A hydrogenated block copolymer having a hydrogenation rate of 4% and a hydrogenation rate of 99% is disclosed in Japanese Patent Laid-Open No.
The component (a-2) was synthesized by the method described in JP-A-1-33132.

Component (a-3) having a structure of BABABAB and having a bound styrene content of 28
% By weight, number average molecular weight 131,000, molecular weight distribution 1.1
2. A hydrogenated block copolymer having a 1,2-vinyl bond content of 41% in the polybutadiene portion before hydrogenation and a hydrogenation ratio of 98% was synthesized by the method described in JP-A-61-33132 ( It was used as the component a-3).

Component (a-4) having a structure of (B-A-B) ₄ -Si, having a bound styrene content of 25% by weight, a number average molecular weight of 196000, a molecular weight distribution of 1.32, and a polybutadiene portion before hydrogenation. A hydrogenated block copolymer having a 1,2-vinyl bond content of 33% and a hydrogenation rate of 99% was synthesized by the method described in JP-A No. 61-33132 to obtain component (a-4).

Component (a-5) having the structure of A-B-A and having a bound styrene content of 29% by weight,
Number average molecular weight 51,000, molecular weight distribution 1.06, polybutadiene portion before hydrogenation has a 1,2-vinyl bond content of 35%,
A hydrogenated block copolymer having a hydrogenation rate of 99% is disclosed in JP-A-61-3.
It was synthesized by the method described in Japanese Patent No. 3132 (a-
5) Used as a component.

Component (b-1) Asahi Kasei Polypropylene; Asahi Polypro M1600, M
FR14g / 10min.

Component (b-2) Asahi Kasei Industrial Polypropylene; Asahi Polypro M3500, M
FR8g / 10min.

Component (c-1) Sumitomo Chemical Co., Ltd .; Excellen VL200MI 2 g / 1
0 min, density 0.900 g / cm ³ , maximum melting peak temperature by DSC 115 ° C., flexural modulus 650 kg / cm ² .

Component (c-2): Nippon Petrochemical; Nisseki Softlex C9005MI
0.8g / 10min, density 0.900g / cm ³ , DSC
Maximum melting peak temperature 119 ° C, flexural rigidity 850
Kg / cm ² .

Examples 1 to 18, Comparative Example 10  As a hydrogenated block copolymerIn Examples 1-8(A-
1) to (a-4)In Comparative Example 10, (a-5)for
(B-1) was used as the propylene resin, and
Use (c-1) as the ethylene-α-olefin copolymer
Henschel mixer at the ratios shown in Tables 1 to 3
After blending with a twin-screw extruder with a diameter of 50 mm, 220
Melt kneading under the condition of ℃ and pellet of elastomer composition
Obtained. This was evaluated by the above test method, and the results are shown in Tables 1 to 3
It was shown to.

In the table, in the items of tensile strength and elongation, MD is a value when a test piece is punched in parallel with the sheet extruding direction, and TD is a value of the test piece perpendicular to the sheet extruding direction. It is the value when punched. From this result, it is clear that the elastomer composition of the present invention is excellent in strength, flexibility, heat resistance and transparency.

Comparative Examples 1 to 4 (a-1) was used as the hydrogenated block copolymer, (b-1) was used as the propylene resin, and ethylene-α was used.
-Using (c-1) as the olefin copolymer, kneading was carried out in the same manner as in Examples 1 to 9 at the respective ratios shown in Tables 4 and 5, followed by molding and evaluation. The results are shown in Table 4 and Table 5.
It was shown to. From these results, the compositions outside the scope of the present invention showed unsatisfactory physical properties in some respects.

Comparative Examples 5 to 6 (a-1) was used as the hydrogenated block copolymer, (b-1) was used as the propylene-based resin, and the ethylene-α-olefin copolymer as the component (c) was replaced. to Mitsui Petrochemical Industries Ltd. ethylene emissions - alpha-olefin copolymer, Tafuma -A
-4090 (MI 3.6g / 10min, density 0.89
g / cm ³ , DSC maximum melting peak temperature of 81 ° C, flexural rigidity of 450 kg / cm ² , or Sumitomo Chemical LDP
E, Sumikasen F221-1 (MI 2g / 10min,
Using a density of 0.923 g / cm ³ , a maximum melting peak temperature of 112 ° C. by DSC, and a flexural modulus of 2400 Kg / cm ² ,
The respective proportions shown in Tables 4 and 5 were kneaded in the same manner as in Examples 1 to 9 and further molded and evaluated. The results are shown in Tables 4 and 5. From this result, it was revealed that a composition having an excellent balance of flexibility and heat resistance cannot be obtained even if a soft resin other than the ethylene-α-olefin copolymer described in the present invention is used.

Examples 9 to 14 and Comparative Examples 7 to 9 (a-1) and (a-2) were used as the hydrogenated block copolymers, and (b-1) and (b-2) were used as the propylene resin.
And (c-1) and (c-2) as the ethylene-α-olefin copolymer, and kneaded in the same manner as in Examples 1 to 8 at each ratio shown in Tables 6 to 8. Then, it was further molded and evaluated. The results are shown in Tables 6 to 8.

[0059]

[Table 1]

[0060]

[Table 2] (Continued from Table 1)

[0061]

[Table 3] (Continued from Tables 1 and 2)

[0062]

[Table 4]

[0063]

[Table 5] (Continued from Table 4)

[0064]

[Table 6]

[0065]

[Table 7] (Continued from Table 6)

[0066]

[Table 8] (Continued from Tables 6 and 7)

Claims (3)

(57) [Claims] 1. A compound comprising (a) at least two vinyl aromatic compounds.
A polymer block A mainly composed of a substance, and at least one
From a polymer block B mainly composed of a conjugated diene compound
BecomeGeneral formula [Chemical 1] (BA) _n , B (AB) _n , [(A-B) _m ] _p -[B (AB) _{m '} ] _q -Z (However, A is a polymer mainly composed of vinyl aromatic compounds.
Block B is a polymer block mainly composed of a conjugated diene compound.
Lock, n is an integer from 2 to 6 and m and m ′ are from 1 to 6
In the following integers, m and m ′ may be the same or different,
p is an integer of 0 or more and 5 or less, q is an integer of 1 or more and 6 or less, p
+ Q is 2 or more and 6 or less, and Z is a functional group having 2 or more functional groups.
Represents the residue of a pulling agent. ) At least one
Having a polymer block B at one polymerization end Block co-weight
Block copolymer obtained by hydrogenating the polymer
%, (B) Propylene homopolymer and / or propylene
And C2-C8 α-olefin copolymer 5-40
% By weight, and (c) ethylene and an α-olefin having 3 to 12 carbon atoms
The density obtained by copolymerization is 0.860 to 0.910.
g / cm³, The melt index is 0.01 to 100 g /
10 min, maximum melting by differential scanning calorimetry (DSC)
Ethylene-α-olphi with a peak temperature of 100 ° C or higher
Flexible and excellent heat resistance consisting of 5-60% by weight of copolymer
Elastomer composition. 2. The vinyl aromatic compound is styrene,
The elastomer composition according to claim 1, wherein the conjugated diene compound is butadiene or isoprene. 3. A polymer block A mainly composed of a vinyl aromatic compound has a number average molecular weight of 4,000 to 50,000, and a polymer block B mainly composed of a conjugated diene compound has a number average molecular weight of 3,000 to 100,000. The elastomer composition according to claim 1, wherein the polymer block A constitutes 10 to 50% by weight of the copolymer.