JP3460306B2 - Thermoplastic elastomer resin composition and method for producing the same - 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 resin composition excellent in compression set resistance and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, as a thermoplastic polyolefin-based elastomer, one mainly composed of polypropylene and ethylene-propylene-based rubber is widely known, but in addition to this, a cross-linked rubber component is acrylonitrile-butadiene rubber, Butyl rubber was used, and further, natural rubber was used.

[0003]

However, the present situation is that none of the composite materials have excellent compression set resistance properties and the substitution in the field of crosslinked rubber has not progressed.

The present invention has been made in view of the above problems, and an object thereof is to provide a thermoplastic elastomer resin composition excellent in compression set resistance and a method for producing the same.

[0005]

The present inventors have completed the present invention as a result of intensive investigations in view of the above-mentioned current situation. That is, the present invention relates to a thermoplastic elastomer resin composition comprising a polypropylene resin (1), an ethylene / α-olefin copolymer rubber (2) and an ethylene / styrene / α-olefin copolymer (3), and its production. Is the law.

The present invention will be described in more detail below.

The present invention relates to a polypropylene resin (1),
A thermoplastic elastomer resin composition comprising an ethylene / α-olefin copolymer rubber (2) and an ethylene / styrene / α-olefin copolymer (3).

The polypropylene resin (1) used in the present invention is, for example, polypropylene homopolymer, propylene / ethylene block copolymer, propylene / ethylene random copolymer, propylene / ethylene / 1-butene random copolymer. Etc. The ethylene or 1-butene content of the copolymer among these polymers is not particularly limited, but the total amount of ethylene and 1-butene is less than 20 mol% in order to maintain the heat resistance of the resulting composition. It is preferable. Further, these polypropylene resins may be used alone or in combination of two or more.

The ethylene / α-olefin copolymer rubber (2) used in the present invention is a copolymer of ethylene and α-olefin.

Examples of the α-olefin of the ethylene / α-olefin copolymer rubber (2) include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1
-Nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicodecene and the like. , Or one or more of these are used. Among them, propylene, 1-butene, 1-hexene, 1-octene and the like are preferable because they are easily available. The α-olefin content is preferably 20 mol% or more and 80 mol% or less in order to maintain flexibility and cold resistance of the resulting composition.

Further, it is preferable that the ethylene / α-olefin copolymer rubber (2) is copolymerized with a non-conjugated diene component as the third component from the viewpoint of improving crosslinkability.
Examples of the non-conjugated diene include 1,4-pentadiene, 1,4-hexadiene, 4-methyl-1,5-heptadiene, 5-methylene-2-norbornene, 5-ethylidene-2-norbornene and 5-iso. Propenyl-2
-Norbornene, 2,5-norbonadiene, 1,6-cyclooctadiene, 2-ethylene-2,5-norbonadiene, 2-isopropenyl-2,5-norbonadiene,
Dicyclopentadiene, 1,6-octadiene, 1,7
-Octadiene, tricyclopentadiene and the like.

Ethylene / styrene / used in the present invention
The α-olefin-based copolymer (3) is a copolymer of ethylene, styrene and α-olefin.

The α-olefin used in the ethylene / styrene / α-olefin copolymer (3) preferably has 4 or more carbon atoms from the viewpoint of improving the mechanical properties of the resulting composition. 4 or more α-olefins include 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1
-Dodecene, 1-tridecene, 1-tetradecene, 1-
Pentadecene, 1-hexadecene, 1-heptadecene,
1-octadecene, 1-nonadecene, 1-eicodecene and the like can be mentioned, and one or more of these can be used. Among them, 1-butene, 1-hexene, 1-octene and the like are preferable because of easy availability.

When only 1-butene is used as the α-olefin, the compatibility with the polypropylene resin (1) is maintained so that the resulting composition has excellent mechanical properties. The content is preferably 45 mol% or more. When an α-olefin having 5 or more carbon atoms is used, the polypropylene resin (1)
In order to make the resulting composition excellent in mechanical properties by maintaining the compatibility with, the α-olefin content is 30%.
It is preferably at least mol%. Where the carbon number is 5
The above α-olefins include, for example, 1-pentene and 1
-Hexene, 1-octene, 1-decene and the like.

Further, the styrene content of the ethylene / styrene / α-olefin copolymer (3) is not particularly limited, but is preferably 0.01 mol% or more and 30 mol% or less. This improves the compatibility with the polypropylene resin (1) and reduces the surface tackiness of the resulting composition.

The molecular weight of the ethylene / styrene / α-olefin copolymer (3) used in the present invention is not particularly limited, but it is easy to handle the copolymer,
In order to easily obtain effective cross-linking, the number average molecular weight measured by gel permeation chromatography (GPC) is preferably 5,000 to 1,000,000 in terms of polyethylene, and more preferably 10,000 to 600,000.

The method for producing the ethylene / styrene / α-olefin copolymer (3) described above is not particularly limited, and various catalysts such as a titanium catalyst, a vanadium catalyst or a metallocene catalyst can be used. Can be used for manufacturing.

The thermoplastic elastomer resin composition of the present invention comprises a polypropylene resin (1), an ethylene / α-olefin copolymer rubber (2) and an ethylene / styrene / α-olefin copolymer (3) listed above. ), And the ethylene / α-olefin copolymer rubber (2) is crosslinked.

The mixing ratio of the polypropylene resin (1), the ethylene / α-olefin copolymer rubber (2) and the ethylene / styrene / α-olefin copolymer (3) is not particularly limited here.

The mixing ratio of the polypropylene resin (1) and the ethylene / α-olefin copolymer rubber (2) is such that the molding processability of the resulting composition and the surface hardness of the composition are maintained. 3 to 10 parts by weight of polypropylene-based resin (1) per 100 parts by weight of ethylene / α-olefin copolymer rubber (2) in order to maintain specific properties.
The amount is preferably 0 parts by weight or less, more preferably 5 parts by weight or more and 50 parts by weight or less.

Further, the blending ratio of the ethylene / styrene / α-olefin copolymer (3) and the ethylene / α-olefin copolymer rubber (2) is set so as to impart elastomeric properties to the resulting composition. To prevent surface stickiness, ethylene / styrene / α-olefin copolymer (3) is an ethylene / α-olefin copolymer rubber (2).
The amount is preferably 3 parts by weight or more and 100 parts by weight or less, more preferably 5 parts by weight or more and 50 parts by weight or less, relative to 100 parts by weight.

The method for producing the thermoplastic elastomer resin composition of the present invention is not particularly limited, but from the viewpoint of improving the physical properties, ethylene / α-olefin copolymer is produced under shearing force when the polypropylene resin (1) is melted. It is preferable to include a step of crosslinking the polymer rubber (2). Also,
From the viewpoint of improving processability, it is preferable to add the ethylene / styrene / α-olefin copolymer (3) after the completion of crosslinking of the ethylene / α-olefin copolymer rubber (2) in the production of the composition of the present invention.

The method for crosslinking the ethylene / α-olefin copolymer rubber (2) in the method for producing the resin composition of the present invention is not particularly limited, but sulfur crosslinking and / or
Alternatively, it is preferably used because the crosslinking time can be shortened by performing peroxide crosslinking.

Examples of the cross-linking agent that can be used for peroxide cross-linking include t-butyl peroxide,
Di-t-butyl peroxide, t-butyl peroxy-isopropyl carbonate, t-butyl cumyl peroxide, t-butyl peroxybenzoate, dicumyl peroxide, cumene peroxide, benzoyl peroxide, cyclohexanone peroxide, diisopropylbenzene peroxide Oxide, 2,5-dimethylhexane-2,5-diperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3,2,5-dimethyl-2,5-di -T-butylperoxyhexane, n-butyl-4,4-bis (t-butylperoxy) hexane, 3,3,5-trimethylhexanoyl peroxide, 2,4-dichlorobenzoyl peroxide, p-chloro Benzoyl peroxide, 1,1-bis ( - butylperoxy) -3,3,
5-trimethylcyclohexane, 2,2'-bis (t-
Butylperoxy) -p-diisopropylbenzene,
1,3-bis (t-butylperoxy-isopropyl)
Examples thereof include benzene, which may be used alone or as a mixture. It is also possible to use it in combination with sulfur crosslinking.

Whether the crosslinking is sulfur crosslinking or peroxide crosslinking, the addition amount of the crosslinking agent is ethylene / α used in the present invention.
-Olefin copolymer rubber (2) is preferably 0.1 to 10 parts by weight per 100 parts by weight. If it is less than 0.1 part by weight, crosslinking may not be sufficiently carried out, and if it exceeds 10 parts by weight, odor may remain in the resulting composition.

Further, it is preferable to use a crosslinking accelerator together with the above-mentioned crosslinking agent at the time of crosslinking the ethylene / α-olefin copolymer rubber (2) because the crosslinking rate is improved. Examples of the crosslinking accelerator include N, N-diphenylguanidine, N, N-di-o-tolylguanidine, N, N-o-
Guanidine derivatives such as tolylguanidine; thioureas such as N, N-dibutylthiourea, N, N'-diethylthiourea, dilaurylthiourea, 2-mercaptoimidazoline, trimethylthiourea, tetramethylthiourea; zinc dibutylxanthogenate, isopropylxanthogenate Xanthate salts such as sodium and zinc isopropylxanthogenate; zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, zinc ethylphenyldithiocarbamate, N-
Zinc pentamethylenedithiocarbamate, Zinc dibenzyldithiocarbamate, Sodium dimethyldithiocarbamate, Sodium diethyldithiocarbamate, Sodium dibutyldithiocarbamate, Copper dimethyldithiocarbamate, Terylium diethyldithiocarbamate, Piperidinium pentamethylenedithiocarbamate, Pipecoline pipecoridimethyl Dithiocarbamate,
Dithiocarbamates such as iron dimethyldithiocarbamate; Aldehyde ammonia-based compounds such as hexamethylenetetramine, acetaldehyde aniline, butyraldehyde aniline; mercaptobenzothiazole, mercaptobenzothiazole sodium salt, dibenzothiazyl disulfide, 2- (4-morpholino dithio ) Thiazol compounds such as benzothiazole and 2- (2,4-dinitrophenyl) mercaptobenzothiazole; tetramethylthiuram monosulfide, tetraethylthiuram monosulfide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide, dipenta Thiuram sulfides such as methylene thiuram tetrasulfide; mercaptobenzothiazole, diben Thiazole compounds such as 2-mercaptobenzothiazole zinc such as disulfide;
Examples thereof include sulfenamide compounds such as N-cyclohexyl-2-benzothiazole sulfenamide, N-oxydiethylene-2-benzothiazole sulfenamide, and Nt-butylbenzothiazole sulfenamide. These crosslinking accelerators may be used alone or in combination of two or more kinds.

When a crosslinking accelerator is used, the amount used is
In order to maintain the moldability of the resulting composition, ethylene /
The amount is preferably 10 parts by weight or less, more preferably 5 parts by weight or less, per 100 parts by weight of the α-olefin copolymer rubber (2).

It is also possible to use a crosslinking promoter and a dispersant typified by zinc white, activated zinc white, surface-treated zinc white, zinc carbonate, litharge and magnesium oxide.

Furthermore, it is effective to use a co-crosslinking agent at the time of crosslinking the ethylene / α-olefin copolymer rubber (2) because the crosslinking effect is improved. As this co-crosslinking agent,
For example, P.quinone dioxime, P.P dibenzoylquinone dioxime, N-methyl-N'-4-dinitrosoaniline, dinitrosobenzene, lauryl methacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate. , Tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, diaryl fumarate, diaryl phthalate, tetraaryloxyethane, triaryl cyanurate, aryl methacrylate, maleimide,
Phenylmaleimide, N, N'm-phenylenebismaleimide, maleic anhydride, itaconic acid, divinylbenzene, diarylmelamine, diphenylguanidine, divinyladipate, vinyltoluene, 1,2-polybutadiene, liquid styrene-butadiene copolymer rubber, Examples include dipentamethylene thiuram pentasulfide, mercaptobenzthiazole, and sulfur.
One kind or two or more kinds are used as necessary.

When a co-crosslinking agent is used, the amount used is ethylene / α in order to maintain the moldability of the resulting composition.
-Olefin copolymer rubber (2) 1 per 100 parts by weight
The amount is preferably 0 parts by weight or less, more preferably 5 parts by weight or less.

The resin composition of the present invention has a molding processability,
A softening agent may be added for the purpose of improving flexibility. Examples of the softening agent include paraffin-based softening agents, naphthene-based softening agents, aroma-based softening agents, asphalt, vaseline, ozokerite, polyethylene wax, and the like, and one or more of these are used. The amount of addition is preferably 100 parts by weight or less with respect to 100 parts by weight of the ethylene / α-olefin copolymer rubber (2) to prevent bleeding of the softening agent. Especially, this addition amount is 3
More than 100 parts by weight, more than 5 parts by weight 6
When the amount is 0 parts by weight or less, excellent moldability is imparted to the composition obtained.

Further, the resin composition of the present invention contains scorch inhibitors represented by phthalic anhydride, benzoic acid, salicylic acid and nitroso compounds, coumarone resins, terpene resins, petroleum hydrocarbon compounds and rosin derivatives. Representative tackifiers can be added as needed. Furthermore, if necessary, calcium carbonate, mica, talc, silica, barium sulfate, calcium sulfate, kaolin, clay, pyroferrite, bentonite, serisanite, zeolite, nepheline sinite, attapulgite, wollastonite, ferrite, calcium silicate, carbonate Inorganic fillers and reinforcing agents such as magnesium, dolomite, antimony trioxide, zinc oxide, titanium oxide, magnesium oxide, iron oxide, molybdenum disulfide, carbon black, gypsum and quartz, as well as organic and inorganic pigments can be blended. . Also, release agents, anti-blocking agents, slip agents, antistatic agents, lubricants, heat resistance stabilizers, light stabilizers, UV absorbers, weather resistance stabilizers, foaming agents, defoamers, rust preventives, anti-mold agents. , Crystallization agent, clarification agent, ion trap agent, flame retardant,
A flame retardant aid or the like may be added if necessary.

Furthermore, it is possible to blend the composition of the present invention with other resins. In this case, it is also possible to use a compatibilizing agent of the composition of the present invention and another resin together as the third component. In particular, blending the composition of the present invention with low-density polyethylene or ultra-low-density polyethylene is preferable because it improves extrusion moldability.

The thermoplastic elastomer resin composition of the present invention is produced by a method including a step of applying a shearing force when the polypropylene resin (1) is melted to crosslink the ethylene / α-olefin copolymer rubber (2). Preferably. Although this method is a method called dynamic crosslinking, the mechanical properties of the composition of the present invention are dramatically improved by using this method. The apparatus used at this time is not particularly limited, and rolls, Banbury mixers, batch type kneaders such as kneaders, screw extruders, continuous kneaders such as rotor type continuous kneaders, etc. may be used alone or in combination. .

Ethylene / styrene / used in the present invention
The α-olefin copolymer (3) becomes a matrix of the composition of the present invention together with the polypropylene resin (1), and plays a major role in improving the compression set resistance, permanent elongation and flexibility which have been problematic so far. . Further, the stress-strain curve in the tensile test also shows a large stress in the region of a relatively small strain in the conventional olefinic thermoplastic elastomer, whereas the resin composition of the present invention does not show a large stress value, and It exhibits crosslinked rubber-like properties. However, when the composition of the present invention is manufactured under severe crosslinking conditions, ethylene / α-
Ethylene / with crosslinking of olefin copolymer rubber (2)
The styrene / α-olefin copolymer (3) may be crosslinked, and the moldability and the physical properties of the resulting composition may be deteriorated. Therefore, for the purpose of preferentially causing crosslinking in the ethylene / α-olefin copolymer rubber (2), it is preferable to use a copolymer of a non-conjugated diene component as the ethylene / α-olefin copolymer rubber (2). . Further, for the same reason as described above, in the production of the composition of the present invention, ethylene / styrene /
It is also preferable to add the α-olefin copolymer (3) after completion of crosslinking of the ethylene / α-olefin copolymer rubber (2).

The composition of the present invention is roughly classified into a completely crosslinked type having almost no uncrosslinked content and a partially crosslinked type having uncrosslinked content depending on the degree of crosslinking of the ethylene / α-olefin copolymer rubber (2). However, the present invention is not limited to these, and in any case, good physical properties are exhibited.

As described above, the composition of the present invention obtained by the above-mentioned method is blended with a reinforcing filler, an inorganic filler and the like, and various molded articles and films are formed by injection molding, extrusion molding, inflation molding and calender molding. It can be formed into a sheet, a tube or the like.

[0038]

The present invention will be described below with reference to examples, but the present invention is not limited thereto.

Synthesis Example 1 Synthesis of ethylene / styrene / 1-butene copolymer To a 5 liter autoclave, 750 ml of toluene, 150 ml of styrene and 600 ml of 1-butene were added, and ethylene was introduced at a rate of 16 kg / cm ² . Next, in another reaction container, 10 ml of toluene and 5 mmol of methylaluminoxane were synthesized by a known method (dimethyl (t-butylamide) (tetramethyl-η5
5 μmol of -cyclopentadienyl) silane) dichloride titanium was added, and the mixed solution was stirred for 20 minutes and then introduced into an autoclave to initiate polymerization. This polymerization was carried out at 90 ° C. for 20 minutes while keeping the ethylene pressure at 16 kg / cm ² .

After completion of the polymerization, the polymer was washed with a large amount of ethanol and dried under reduced pressure at 60 ° C. for 12 hours. As a result, the styrene content was 2 mol% and the 1-butene content was 47.
32 g of a mol% ethylene / styrene / 1-butene copolymer was obtained. This copolymer has a number average molecular weight of 30,000,
It was Mw / Mn = 1.9.

Synthesis Example 2 Synthesis of ethylene / styrene / 1-hexene copolymer To a 2 liter autoclave, 250 ml of toluene, 50 ml of styrene and 300 ml of 1-hexene were added, and ethylene was introduced at a rate of 16 kg / cm ² . Next, in another reaction container, 10 ml of toluene and 5 mmol of methylaluminoxane were synthesized by a known method (dimethyl (t-butylamide) (tetramethyl-η5
5 μmol of -cyclopentadienyl) silane) dichloride titanium was added, and the mixed solution was stirred for 20 minutes and then introduced into an autoclave to initiate polymerization. This polymerization was carried out at 90 ° C. for 30 minutes while keeping the ethylene pressure at 16 kg / cm ² .

After completion of the polymerization, the polymer was washed with a large amount of ethanol and dried under reduced pressure at 60 ° C. for 12 hours. As a result, the styrene content was 2 mol% and the 1-hexene content was 3
30 g of a 4 mol% ethylene / styrene / 1-hexene copolymer was obtained. This copolymer has a number average molecular weight of 5,400.
0 and Mw / Mn = 2.0.

Example 1 100 parts by weight of ethylene / propylene copolymer rubber (JSREP51, manufactured by Japan Synthetic Rubber Co., Ltd.) containing a non-conjugated diene as a copolymerization component, polypropylene resin (Tosoh Polypro J5100A, manufactured by Tosoh Corp.) 17.5 parts by weight, mineral oil-based softener (Diana Process Oil PW-3
80, manufactured by Idemitsu Kosan Co., Ltd.) 35 parts by weight, heat stabilizer (2,2′-methylene-bis- (4-ethyl-6-tert-butylphenol), manufactured by Ouchi Shinko Chemical Industry Co., Ltd.) 2
2 parts by weight of a cross-linking agent (Perhexin 25B-40, manufactured by NOF CORPORATION) and 1 part by weight of a co-crosslinking agent (Sunester (TM) TMP, manufactured by Sanshin Chemical Industry Co., Ltd.) The mixture was put into a Brabender mixer of 100 cc and a temperature of 180 ° C., and kneaded at a rotation speed of 140 rpm for 5 minutes. 17.5 parts by weight of the ethylene / styrene / 1-butene copolymer synthesized in Synthesis Example 1 was added to the material thus obtained, and the mixture was kneaded for 5 minutes with a roll molding machine whose surface temperature was set to 180 ° C.

The obtained roll sheet was JISK6301
According to the procedure described above, a sample for compression set was press-molded to obtain the desired composition, and the compression set was measured. The results are shown in Table 1.

[0045]

[Table 1]

Example 2 100 parts by weight of ethylene / propylene copolymer rubber (JSREP51, manufactured by Japan Synthetic Rubber Co., Ltd.) containing a non-conjugated diene as a copolymerization component, polypropylene resin (Tosoh Polypro J5100A, manufactured by Tosoh Corp.) 17.5 parts by weight, mineral oil-based softener (Diana Process Oil PW-3
80, manufactured by Idemitsu Kosan Co., Ltd.) 35 parts by weight, heat stabilizer (2,2′-methylene-bis- (4-ethyl-6-tert-butylphenol), manufactured by Ouchi Shinko Chemical Industry Co., Ltd.) 2
2 parts by weight, a cross-linking agent (Perhexin 25B-40, manufactured by NOF CORPORATION), and 1 part by weight of a co-crosslinking agent (Sunester (TM) TMP, manufactured by Sanshin Chemical Industry Co., Ltd.) The mixture was put into a Brabender mixer of 100 cc and a temperature of 180 ° C., and kneaded at a rotation speed of 140 rpm for 5 minutes. 17.5 parts by weight of the ethylene / styrene / 1-hexene copolymer synthesized in Synthesis Example 2 was added to the material thus obtained, and the mixture was kneaded for 5 minutes with a roll molding machine whose surface temperature was set to 180 ° C.

The obtained roll sheet was JISK6301
According to the procedure described above, a sample for compression set was press-molded to obtain the desired composition, and the compression set was measured. The results are also shown in Table 1.

Example 3 Linear low density polyethylene resin (Nipolon ™ -L)
F20, manufactured by Tosoh Corp.) was mixed with 5 parts by weight of a polypropylene resin and newly added, and a target composition was obtained in the same manner as in Example 2 and the compression set was measured. The results are also shown in Table 1.

Example 4 Instead of the polypropylene resin used in Example 1, an ethylene-propylene copolymer resin (Tosoh Polypro J6) was used.
080A, manufactured by Tosoh Corporation was used, and the target composition was obtained and the compression set was measured in the same manner as in Example 1. The results are also shown in Table 1.

Comparative Example 1 A composition was obtained in the same manner as in Example 1 except that the polypropylene resin was 35 parts by weight and the ethylene / styrene / 1-butene copolymer was not used, and the compression set was measured. It was The results are also shown in Table 1.

<Measurement of compression set> According to JIS K6301, the measurement was carried out at a temperature of 70 ° C. and a treatment time of 22 hours.

[0052]

As described above, the thermoplastic elastomer resin composition of the present invention is a material having excellent compression set resistance.

Claims (4)

(57) [Claims] 1. A polypropylene resin (1), an ethylene / α-olefin copolymer rubber (2) and an ethylene / styrene / α-olefin copolymer (3) , and
For ethylene / styrene / α-olefin copolymer (3)
The thermoplastic elastomer resin composition, wherein the α-olefin used is one having 4 or more carbon atoms . 2. The styrene content of the ethylene / styrene / α-olefin copolymer (3) is 0.01 mol% or more and 30.
The thermoplastic elastomer resin composition according to claim 1, wherein the content is 1 mol% or less, the α-olefin is 1-butene, and the 1-butene content is 45 mol% or more. 3. An ethylene / styrene / α-olefin copolymer (3) having a styrene content of 0.01 mol% or more 30
The thermoplastic elastomer resin composition according to claim 1, wherein the content of the α-olefin is 5 mol% or less, the α-olefin has 5 or more carbon atoms, and the α-olefin content is 30 mol% or more. 4. A polypropylene resin (1) and ethylene
/ Alpha-olefin copolymer rubber (2) mixed in advance, a shearing force during the melt of the polypropylene resin (1), after crosslinking the ethylene / alpha-olefin copolymer rubber (2)
Ethylene / styrene / α-olefin copolymer
(3) is mixed, Claim 1-Claim 3 characterized by the above-mentioned.
The method for producing the thermoplastic elastomer resin composition according to item 1.