JPH0639555B2 - Thermoplastic polymer composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermoplastic polymer composition suitable for obtaining a film having excellent moldability, flexibility, stretchability and heat resistance.

[Conventional technology]

In recent years, various thermoplastic elastomers (hereinafter referred to as TPE) have been developed as polymer materials that show elastic properties like vulcanized rubber at room temperature and have moldability similar to thermoplastic resin at high temperature. Exterior parts, medical equipment, footwear,
It is being used for electric wire coatings, home electric appliances, toys, etc.

Among these TPEs, polystyrene-polybutadiene-polystyrene block copolymer (SBS), styrene thermoplastic elastomer such as block copolymer (SEBS) saturated with polybutadiene block of SBS by hydrogenation, and crystals of olipropylene, polyethylene, etc. Performance and price of olefin-based thermoplastic elastomers such as a blend of water-soluble polyolefin and ethylene / propylene copolymer rubber (EPM), ethylene / propylene / diene terpolymer rubber (EPDM) or a partially crosslinked EPM / EPDM Most often used because of its balance. However,
In terms of performance, styrene thermoplastic elastomers are excellent in flexibility and stretchability, but inferior in heat resistance, weather resistance and moldability, while olefin thermoplastic elastomers are excellent in weather resistance and flexibility, but moldability and stretchability. If it is inferior to that, there are merits and demerits as always.

Styrene-based TPE is used as a composition and the like in which such drawbacks are improved
Elastic tape with polyolefin resin added to the
59-155478), styrene-based TPE and olefin-based TP
A method of mixing E and the like (JP-A-58-222143, JP-A-59)
No. 6236), a film comprising a styrene-based TPE or the like and an ethylene / 1-butene copolymer has been proposed.
However, these tapes cannot be said to have sufficient balance between heat resistance and stretchability. Further, the method (1) does not improve the stretchability and the film formability, and the film (2) does not improve the heat resistance, and even in the slippage method, a composition having a good balance between the formability and the performance is obtained. The current situation is that it has not been done.

[Problems to be solved by the invention]

In view of such a situation, the present inventor has variously studied to obtain a thermoplastic polymer composition suitable for obtaining a film excellent in moldability and having excellent flexibility, stretchability and heat resistance, resulting in low crystallinity or Thermoplastic polymer composition comprising amorphous ethylene / α-olefin random copolymer and / or low crystalline propylene / α-olefin random copolymer and olefin-based thermoplastic elastomer and styrene-based thermoplastic elastomer Has been found to have the above-mentioned characteristics, and the present invention has been completed.

[Means for solving problems]

That is, the present invention provides (a) an ethylene / α-olefin random copolymer (A) having an X-ray crystallinity of 0 to 50% and an ethylene content of 55 to 95 mol% and / or an X-ray crystallization. Degree 0
To 50% and a propylene content of 55 to 85 mol% propylene / α-olefin random copolymer (B) 15 to 50% by weight, (b) peroxide crosslinkable olefin copolymer rubber (a) 40 to 90% by weight Part, peroxide decomposition type olefin resin
(b) 60 to 10 parts by weight, and (a) + (b) = 100 parts by weight, peroxidic non-crosslinked hydrocarbon rubber-like substance (c) and / or mineral oil-based softening agent (d) 5 To 100 parts by weight of olefinic thermoplastic elastomer (C) partially crosslinked by dynamically heat-treating the mixture in the presence of organic peroxide, and (c) monovinyl aromatic hydrocarbon. An olefin block copolymer (D) of 20 to 50% by weight, which is suitable for obtaining a film having excellent moldability, particularly excellent extrusion moldability, and flexibility, elasticity and heat resistance. A thermoplastic polymer composition is provided.

[Action]

The ethylene / α-olefin random copolymer (A) used in the present invention has an X-ray crystallinity of 0 to 50%, preferably 1 to 30% and an ethylene content of 55 to 95 mol%, preferably 75. To 93% normal melt flow rate (MFR ₂ : ASTM D 1238, L) 0.1 to 50 g / 10 m
in, preferably 0.6 to 40 g / 10 min, normal density 0.85
0 to 0.900 g / cm ³ , preferably 0.855 to 0.895 g
It is a random copolymer of ethylene / cm ³ and α-olefin usually having 3 to 20 carbon atoms.

If the crystallinity exceeds 50%, the flexibility is poor, and if the ethylene content is less than 55 mol%, the surface properties of the molded product deteriorate. On the other hand, if it exceeds 95 mol%, the flexibility and stretchability are not improved. MFR ₂ is not particularly limited, but if it is out of the above range, moldability tends to be poor. Density correlates with crystallinity and ethylene content. Specific examples of α-olefin copolymerized with ethylene include propylene and 1-
Butene, 4-methyl-1-pentene, 1-hexene, 1
-Octene, 1-decene, 1-tetradecene, 1-octadecene and the like, each being a single compound or a mixture of two or more compounds.

The propylene / α-olefin random copolymer (B) used in the present invention has an X-ray crystallinity of 0 to 50%, preferably 1 to 45% and a propylene content of 55 to 50%.
85 mol%, preferably 60 to 80 mol% of normal MFR ₂
0.5 to 50g / 10min, preferably 1 to 15g / 10mi
It is a random copolymer of n propylene and α-olefin having 3 to 20 carbon atoms, and preferably has a melting point of 130 ° C or lower, more preferably 80 to 120 ° C.

If the crystallinity exceeds 50%, the flexibility is poor, and if the propylene content is less than 55 mol%, the surface properties of the molded product deteriorate. On the other hand, if it exceeds 85 mol%, the flexibility and stretchability are not improved.

MFR ₂ is not particularly limited, but if it is out of the above range, moldability tends to be poor. The melting point correlates with the crystallinity and the propylene content, and those exceeding 130 ° C tend to lack flexibility and stretchability. Specific examples of α-olefin copolymerized with propylene include ethylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, and 1-octene.
-Decene, 1-tetradecene, 1-octadecene, etc., each being a single compound or a mixture of two or more compounds. Among them, α-olefin having 4 or more carbon atoms is preferable in terms of moldability and mechanical properties. A method for producing such a propylene / α-olefin random copolymer is described in JP-B-57-11322.
For details, see Japanese Examined Patent Publication No. 60-21643.

Olefin-based thermoplastic elastomer used in the present invention (C)
Is a peroxide cross-linked olefin copolymer rubber (a) 40
To 90 parts by weight, preferably 50 to 80 parts by weight, peroxide decomposition type olefin resin (b) 60 to 10 parts by weight,
Preferably, 50 to 20 parts by weight, and (a) + (b) = 100 parts by weight, based on a non-peroxide type hydrocarbon rubbery substance
(c) and / or mineral oil softener (d) 5 to 100 parts by weight,
A thermoplastic elastomer partially crosslinked by dynamically heat treating a mixture of 5 to 30 parts by weight of component (c) and 5 to 60 parts by weight of component (d) in the presence of organic peroxide.

The peroxide-crosslinking type olefin copolymer rubber (a) in the present invention contains olefin as a main component, for example, ethylene-propylene copolymer rubber, ethylene-propylene-non-diene diene rubber, ethylene-butadiene copolymer rubber. It refers to a rubber in which an amorphous random elastic copolymer is prepared and mixed with a peroxide, and the mixture is kneaded under heating to crosslink so that the fluidity decreases or the fluidity stops. Among these, ethylene-propylene copolymer rubber, ethylene-propylene-non-co-diene diene rubber (here, non-co-diene diene, dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, methylene norbornene, ethylidene Norbornene, etc.) is particularly preferable, and ethylene-propylene-non-co-diene diene copolymer rubber, especially ethylene-propylene-ethylidene-norbornene copolymer rubber is heat-resistant, tensile properties, and olefin resin having excellent impact resilience. It is particularly preferable in that a plastic elastomer (C) can be obtained. Mooney viscosity of copolymer rubber ML _{1 + 4} (1
00 ° C) is preferably 10 to 250, especially 70 to 200,
When the Mooney viscosity is less than 10, only an olefin-based thermoplastic elastomer having poor tensile properties can be obtained, whereas when it exceeds 250, the fluidity of the olefin-based thermoplastic elastomer becomes poor, which is not preferable. Further, the iodine value (unsaturation degree) of the rubber is preferably 16 or less, and in this range, a partially crosslinked olefin thermoplastic elastomer (C) having a good balance of fluidity and rubber properties can be obtained.

Peroxide decomposition type olefin resin in the present invention
(b) is an olefin resin that is mixed with peroxide and thermally decomposed by kneading under heating to reduce the molecular weight and increase the fluidity of the resin, such as isotactic polypropylene and propylene. Of a small amount of α-olefin, such as propylene-ethylene copolymer, propylene-1-butene copolymer, propylene-
1-hexene copolymer, propylene-4-methyl-1-
Examples thereof include pentene copolymers. Melt flow rate (MFR ₂ ) of olefin resin mixed is 0.1
It is preferably in the range of 5 to 50 g / 10 min, particularly 5 to 20 g / 10 min. In the present invention, the olefin resin has a role of improving the inductivity and heat resistance of the olefin thermoplastic elastomer (C). Component (a) + (b) component 1 in olefin thermoplastic elastomer (C)
The amount of the olefin resin of (b) relative to 00 parts by weight should be in the range of 10 to 60 parts by weight, preferably 20 to 50 parts by weight, and when it exceeds 60 parts by weight, the flexibility and repulsion of the olefin thermoplastic elastomer are increased. Elasticity is impaired. On the other hand, if the amount of the olefin resin is less than 10 parts by weight, the heat resistance and fluidity of the olefin thermoplastic elastomer will be impaired, and it will not be suitable for the purpose of the present invention.

Next, the peroxide non-crosslinking hydrocarbon rubber-like substance (c) in the present invention means, for example, polyisobutylene, butyl rubber, propylene 70 mol% or more propylene-ethylene copolymer rubber, propylene-1-butene copolymer. Rubber,
A hydrocarbon rubber-like substance, such as isotactic polypropylene, which does not crosslink even when mixed with peroxide and kneaded under heating and does not deteriorate in fluidity. Of these, polyisobutylene is the most preferable in terms of performance and handling. In the present invention, the term "crosslinking" refers to a phenomenon in which the apparent molecular weight of the polymer increases as a result of many crosslinking reactions in the competitive reaction between the decomposition reaction and the crosslinking reaction that occur when the polymer is thermally reacted with peroxide. The term "decomposes" refers to a reaction phenomenon in which the apparent molecular weight of a polymer decreases as a result of the large number of decomposition reactions. The hydrocarbon rubbery substance (c), particularly polyisobutylene, preferably has a Mooney viscosity of 60 or less in order to improve the fluidity of the olefin thermoplastic elastomer. The compounding amount of the rubber-like substance in (c) is the same as in (a) above.
Component + (b) Component 0 to 40 parts by weight, preferably 5 to 30 parts by weight, based on 100 parts by weight. If the amount is more than the above range, heat resistance and tensile properties of the olefin thermoplastic elastomer may be deteriorated. When the degree of cross-linking of the rubber of (a) is too small, the same drawbacks are brought about.

The mineral oil-based softening agent (d) in the present invention usually weakens the intermolecular action force of the rubber during roll processing, facilitates processing, and assists or disperses carbon black, white carbon, etc. It is a high boiling point petroleum fraction used for the purpose of lowering the hardness of the vulcanized rubber and increasing the flexibility and elasticity, and is classified into paraffin type, naphthene type, aromatic type and the like. The amount of the mineral oil-based softening agent (d) used in the present invention is 0 to 60 parts by weight, preferably 5 to 60 parts by weight, particularly 10 to 40 parts by weight, based on 100 parts by weight of the components (a) + (b). Is. When the amount of the softening agent exceeds the above range, the heat resistance of the olefin thermoplastic elastomer decreases. Alternatively, the softening agent exudes and has a bad influence on the appearance. The ratio of the components (c) and / or (d) to the components (a) + (b) is
The amount is 5 to 100 parts by weight, preferably 10 to 80 parts by weight, particularly 20 to 70 parts by weight, relative to 100 parts by weight of the components (a) + (b). If the amount of the components (c) and / or (d) is less than 5 parts by weight, the sufficient fluidity improving effect aimed at by the present invention cannot be obtained. On the other hand, if it exceeds 100 parts by weight, the olefin-based heat cannot be obtained. Physical properties such as heat resistance and tensile properties of the plastic elastomer are significantly reduced.

Examples of organic peroxides used for crosslinking or decomposing rubbers and resins include dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert-butylperoxy) hexane and 2 , 5-Dimethyl-2,5-di (tert-butylperoxy) hexyne-3,
1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3,3,5
-Trimethylcyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4
-Dichlorobenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, tert-butyl cumyl peroxide and the like can be mentioned. Among these, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane and 2,5-dimethyl-2,5-di (tert
-Butylperoxy) hexyne-3,1,3-bis (tert-
Butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane and n-butyl-4,4-bis (tert-butylperoxy) valerate are preferable 1,3 Most preferred is -bis (tert-butyltylperoxyisopropyl) benzene.

The content of the organic peroxide should be selected so that it is preferably in the range of 0.05 to 1.0% by weight, particularly 0.1 to 0.5% by weight, based on the whole object to be treated. When the compounding amount is less than 0.05% by weight, the degree of crosslinking of the crosslinkable rubber of (a) is too small, resulting in rubber properties such as heat resistance, tensile properties, elastic recovery and impact resilience of the olefin thermoplastic elastomer (C). On the other hand, if it exceeds 1.0% by weight, the degree of crosslinking of the peroxide crosslinkable rubber (a) increases, and as a result, the fluidity of the entire composition decreases.

Olefin-based thermoplastic elastomer used in the present invention (C)
In the method for producing the above-mentioned compound, sulfur, p-quinonedioxime, p,
p'-dibenzoylquinone dioxime, N-methyl-N,
Peroxy vulcanization aids such as 4-dinitrosoaniline, nitrobenzene, diphenylguanidine, trimethylolpropane-N, N'-m-phenylenedimaleimide, or divinylbenzene, triallyl cyanurate, ethylene glycol dimethacrylate, diethylene glycol It is possible to incorporate polyfunctional methacrylate monomers such as dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, allyl methacrylate, polyfunctional vinyl monomers such as vinyl butyrate or vinyl stearate. With such a compound, a uniform and mild crosslinking reaction can be expected. In particular, in the present invention, when divinylbenzene is used, it is easy to handle, and the compatibility with the peroxide-crosslinking type olefin copolymer rubber (a) and the peroxide-decomposing type olefin resin (C), which are the main components of the object to be treated, is improved. It has a good organic peroxide solubilizing effect and acts as a dispersion aid for peroxides, so the crosslinking effect by heat treatment is uniform, and an olefin-based thermoplastic elastomer (C) with a well-balanced fluidity and physical properties is obtained. It is most preferable because Olefin thermoplastic elastomer
In the production of (C), the compounding amount of such a crosslinking aid or a polyfunctional vinyl monomer is based on the whole object to be treated.
The range of 0.1 to 2% by weight, particularly 0.3 to 1% by weight is preferable, and if the amount exceeds 2% by weight, the crosslinking reaction will proceed if the amount of the organic peroxide compounded is large, resulting in the fluidity of the olefin thermoplastic elastomer. Is inferior, while
If the amount of organic peroxide is small, it will be present in the olefin-based thermoplastic elastomer as an unreacted monomer, and the physical properties will change due to the thermal covering history during processing and molding of the olefin-based thermoplastic elastomer, resulting in excessive compounding. Should be avoided.

In the production of olefin-based thermoplastic elastomer (C), in order to accelerate the decomposition of organic peroxide, tertiary amines such as triethylamine, tributylamine, 2,4,6-tris (dimethylamino) phenol, and aluminum are also used. It is also possible to use naphthenic hydrochloric acid such as cobalt, vanadium, copper, calcium, zirconium, manganese, magnesium, lead and mercury, and organic metal carboxylates such as octanoate.

The method for producing such an olefin thermoplastic elastomer (C) is described in detail in JP-B-56-15741 and JP-B-54-23702.

The monovinyl aromatic hydrocarbon / olefin block copolymer (D) used in the present invention has the general formula (AB) _n , Or (In the formula, A and A'are monovinyl aromatic hydrocarbon polymer blocks, B is an olefin polymer block, n is an integer of 1 to 5, m is an integer of 2 to 7, and X is a polyfunctional group having a valence of m. A polymer having a block structure in which at least one terminal is a monovinyl aromatic hydrocarbon polymer block having a linear structure or a branched structure represented by the formula (1). Preferred monovinyl aromatic hydrocarbons are styrene and α-methylstyrene, with styrene being especially preferred. Examples of olefins include conjugated diolephins such as butadiene and isoprene, and α-olefins such as ethylene, propylene and 1-butene. Further, the polymer block obtained by polymerizing the conjugated diolefin may be hydrogenated.
In addition, block B is, as long as the olefin units dominate,
It may be a copolymer of styrene, α-methylstyrene with butadiene, isoprene or the like. The amount of the monovinyl aromatic hydrocarbon polymer block contained in the component (d) is usually 8 to
It is 55% by weight, preferably 10 to 35% by weight, and preferably both ends are monovinyl aromatic hydrocarbon polymer blocks. These block copolymers are, for example, Cauliflex T
R, Kraton G (Both are trade names, Ciel Chemical Co., Ltd.)
It is manufactured and sold as

The thermoplastic polymer composition of the present invention comprises the above (a) ethylene / α-olefin random copolymer (A) and / or propylene / α-olefin random copolymer.
(B) 15 to 50% by weight, preferably 20 to 40% by weight, (B) olefin thermoplastic elastomer (C) 20 to 55% by weight, preferably 30 to 50% by weight, and (C) monovinyl aromatic carbonization The hydrogen / olefin block copolymer (D) is composed of 20 to 50% by weight, preferably 25 to 40% by weight.

Ethylene / α-olefin random copolymer (A) and /
Or propylene / α-olefin random copolymer (B)
If the amount is less than 15% by weight, moldability is poor. On the other hand, 50% by weight
If it exceeds, the permanent set of the molded product such as the molded film becomes large.

20% by weight of olefin thermoplastic elastomer (C)
If it is less than 55% by weight, heat resistance is poor. On the other hand, if it exceeds 55% by weight, a molded product such as a molded film has a large permanent strain and sufficient stretchability cannot be obtained.

If the amount of the monovinyl aromatic hydrocarbon / olefin block copolymer (D) is less than 20% by weight, the permanent set and stretchability of the molded article are not improved. On the other hand, if it exceeds 50% by weight, the moldability and heat resistance are poor.

To obtain the thermoplastic polymer composition of the present invention, ethylene
α-olefin random copolymer (A) and / or propylene / α-olefin random copolymer (B), olefin thermoplastic elastomer (C) and monovinyl aromatic hydrocarbon / olefin block copolymer (D) Within the above range by various known methods such as Henschel mixer, V-blender, ribbon blender, tumbler blender, etc., or after mixing, after melt-kneading with a single-screw extruder, twin-screw extruder, kneader, Banbury mixer, etc. A method of granulating or crushing may be adopted.

The thermoplastic polymer composition of the present invention contains a weather stabilizer, a heat stabilizer, an antistatic agent, a lubricant, a slip agent, a nucleating agent, a flame retardant, a pigment, a dye, an inorganic or organic filler, and the like. You may mix | blend in the range which does not spoil.

(Effects of the Invention) The thermoplastic polymer composition of the present invention has a low motor load and resin pressure during extrusion molding, and has excellent moldability such as film molding, so that it can be easily applied to films, tapes, sheets, tubes and the like. Since it can be processed and the obtained molded product is thermoplastic, it can be easily bonded by heat sealing. Among them, the film is excellent in stretchability and thin-wall moldability, so that it can be used as a sanitary material such as a gear gather portion for improving the adhesion of the thighs of a paper diaper, an adhesion protection film, a rubber cord product, and the like.

〔Example〕

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples as long as the gist thereof is not exceeded.

Example 1 <Production of olefin-based thermoplastic elastomer> EPT (ethylene-propylene-2-ethylidene-5-norbornene terpolymer (ethylene content 78 mol%, iodine value 15, Mooney viscosity ML _{1 + 4} (100 ° C.) ) 160] 7
5 parts by weight, PP (crystalline polypropylene [MFR ₂ 11g / 10mi
n, density 0.91 g / cm ³ ) 25 parts by weight, IIR (isobutene-isoprene copolymer elastomer [unsaturation degree 0.8 mol%,
Mooney viscosity ML _{1 + 4} (100 ° C.) 45]) 25 parts by weight and paraffinic process oil 42 parts by weight and antioxidant tetrakis [methylene (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] 0.3 part of methane was put into a "Banbury mixer", and the mixture was kneaded at 180 ° C for 15 minutes in a nitrogen atmosphere, and then cut into a sheet through a roll into a "pellet".

Next, a solution prepared by dissolving 0.4 parts of 1,3-bis (tert-butylperoxy-iso-propyl) benzene in 0.4 parts of divinylbenzene and 0.2 parts of process oil was added to the pellet and mixed with a Henschel mixer. After mixing, the solution was evenly adhered to the pellet surface.

Then, the pellets were extruded in an atmosphere of nitrogen,
It is extruded at 210 ° C for a residence time of 2 minutes, and the pellet is dynamically heat treated to obtain an olefin-based thermoplastic elastomer (TP
E-I) was obtained.

<Production and Evaluation of Thermoplastic Polymer Composition> Crystallinity by X-ray 5%, ethylene content 80 mol%, MF
20% by weight of ethylene / propylene random copolymer (EPC-I) having R ₂ = 0.8 g / 10 min and a density of 0.865 g / cm ³ , the above T
PE-I 50% by weight and polybutadiene-polybutadiene-polystyrene block copolymer polybutadiene block hydrogenated product (trade name: Kraton G1657: manufactured by Shell Chemical Co., Ltd., styrene content: 14% by weight: hereinafter abbreviated as SEBS) 30 65% φ after mixing with wt% by Hensiel mixer
Granulation was performed with an extruder (set temperature: 230 ° C). The film is formed by 40 mmφ, T-die forming machine (set temperature: 230
℃, T-die lip opening: 0.3mm), thickness 50μ
I made it by pulling down to make it a film.

The film obtained by the above method was evaluated by the following method. The results are shown in Table 1.

(1) Moldability: Thin film (50μ) on T-die molding machine
Judgment based on the degree of molding difficulty.

◯: A film having a uniform film thickness can be formed without any problem.

Δ: Thickness unevenness sometimes occurs at the time of drop molding.

X: The melted film is broken during the draw-down molding and cannot be molded.

(2) Heat resistance: A 4 mmφ SUS ball heated to 125 ° C. was placed on a strip-shaped film that maintained 50% elongation, and the presence or absence of perforation was judged while left at room temperature.

○: No holes are formed in the film.

X: A hole is formed in the film.

(3) Permanent set: A strip-shaped test piece with a width of 25 mm was set in a tensile tester (manufactured by Instron) (span interval =
_o ^* ) ¹ , same speed immediately after stretching up to 200% ^{* 2}
Span interval when the tensile stress is reduced to zero
Was calculated by the following formula.

^* 1 _o = 10 cm ^* 2 300 mm / min Example 2 Used in the production of the thermoplastic polymer composition of Example 1.
Instead of EPC-I, crystallinity by X-ray 10%, ethylene content 90 mol%, MFR ₂ 6.7 g / 10 min and density 0.885 g
The same procedure as in Example 1 was carried out except that a random copolymer of ethylene / butene (EBC-I) / cm ³ was used. The results are shown in Table 1.

Example 3 Used in the preparation of the thermoplastic polymer composition of Example 1.
Instead of EPC-I, X-ray crystallinity 20%, propylene content 71 mol%, MFR ₂ 6.0 g / 10 min and density 0.890 g
/ 10 min propylene-butene random copolymer (PBC-
Example 1 was repeated except that I) was used. The results are shown in Table 1.
Shown in.

Examples 4 to 5 Compositions similar to those in Example 2 were blended in the proportions shown in Table 1, and the same evaluations as in Examples 1 to 3 were performed. The results are shown in Table 1.

It is apparent that the composition of the present invention is excellent in moldability, heat resistance and stretchability in any of the systems of Examples 1 to 5 described above.

Comparative Examples 1-2 Although the same evaluation was performed on the EPC-I simple substance used in Example 1 and the blend system of EPC-I and SEBS, all of them are excellent in moldability and stretchability, Inferior in heat resistance.

Comparative Examples 3 to 4 Similar evaluations were performed using the TPE-I used alone in Example 1 and the blend system of TPE-I and SBES. As a result, the formability of the thin film is inferior.

Comparative Examples 5 to 6 Compositions similar to those in Example 2 were blended in the ratios shown in Table 1 and evaluated in the same manner as the others, but EBC-
When I is small, moldability is poor, and when EBC-I is too large, stretchability is poor.

Claims (1)

[Claims] 1. (a) Ethylene.α-having a crystallinity by X-ray of 0 to 50% and an ethylene content of 55 to 95 mol%.
Olefin random copolymer (A) and / or 15 to 50% by weight of propylene / α-olefin random copolymer (B) having a crystallinity of 0 to 50% by X-ray and a propylene content of 55 to 85 mol%. , (B) Peroxide cross-linking type olefin copolymer rubber (a) 40 to 90 parts by weight, peroxide decomposing type olefin resin
(b) 60 to 10 parts by weight, and (a) + (b) = 100 parts by weight, peroxy non-crosslinked hydrocarbon rubber-like substance (c) and / or mineral oil-based softening agent (d) 5 To 100 parts by weight of olefinic thermoplastic elastomer (C) partially crosslinked by dynamically heat-treating the mixture in the presence of organic peroxide, and (c) monovinyl aromatic hydrocarbon. A thermoplastic polymer composition comprising 20 to 50% by weight of an olefin block copolymer (D).