JP2001192490A - Thermoplastic resin composition for foaming, foamed molded article and method for producing the same - Google Patents

Abstract

(57) [Abstract] (Modified) [Problem] A foam molded article excellent in recyclability and disposal property, capable of simplifying a production process, and having a good balance of flexibility, heat resistance and impact resistance. The present invention provides a thermoplastic resin composition for foaming capable of obtaining the following. SOLUTION: It contains the following components (A) and (B),
A thermoplastic resin composition for foaming, wherein the weight ratio of (A) / (B) is from 95/5 to 5/95. (A): Amorphousness in which the flexural modulus (Ua (MPa)) of the resin composition (b) obtained by blending with the homopolypropylene resin (a) measured according to JIS K7203 satisfies the following formula (1). Olefin (co) polymer Ua ≦ 1.5 × Sa × (Ta / 100) ^3.3
(1) (Sa represents the flexural modulus (MPa) measured according to JIS K7203 of (a), and Ta represents the content (% by weight) of (a) in (b).) (B) ): Thermoplastic resin (however, excluding the above (A))

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermoplastic resin composition for foaming, a foamed molded article, and a method for producing the same. More specifically, the present invention relates to a foaming thermoplastic resin composition containing a specific amorphous olefin (co) polymer and a thermoplastic resin, which has excellent recyclability and simplification of a production process. The present invention relates to a thermoplastic resin composition for foaming capable of obtaining a foamed molded article which is possible and has a good balance of flexibility, heat resistance and impact resistance, a foamed molded article using the same, and a method for producing the same. .

[0002]

2. Description of the Related Art Conventionally, automobile interior parts such as instrument panels, door trims, console lids, and pillar garnishes have been required to have a flexible feel in order to have a high-grade feel. Various foams such as foamed polyurethane are used as a pad layer as a backing material for a skin material made of a thermoplastic elastomer or the like. On the other hand, with the rise of environmental problems in recent years, there is high expectation for flexible foamed materials made of olefin-based materials that are advantageous in terms of recycling, and a special cross-linked foaming technology is used as a thermoplastic olefin-based elastomer pad layer as a skin. An all-olefin interior material using a high expansion ratio polyolefin material as a backing material has also been developed. However, in these methods, in order to achieve a high degree of flexibility, in the production of the backing material, high foaming after a cross-linking reaction is indispensable, and improvements in recyclability and the production process are desired. ing.

As a method for solving such a problem, there has been proposed a method in which an olefinic thermoplastic elastomer obtained by foaming at the time of injection molding is applied, but only a foamed molded article having a low expansion ratio can be obtained. The bubbles are easily broken and become open cells, and it has been difficult to obtain a soft feel like a conventional automobile interior part.

[0004]

Under such circumstances,
The problem to be solved by the present invention is a thermoplastic resin composition for foaming containing a specific amorphous olefin (co) polymer and a thermoplastic resin, which has excellent recyclability and simplifies the production process. The present invention provides a thermoplastic resin composition for foaming capable of obtaining a foamed molded article which is capable of obtaining a foamed molded article having a good balance of flexibility, heat resistance and impact resistance, a foamed molded article using the same, and a method of producing the same It is in.

[0005]

That is, a first aspect of the present invention comprises the following components (A) and (B):
The present invention relates to a thermoplastic resin composition for foaming wherein the weight ratio of (A) / (B) is from 95/5 to 5/95. (A): Amorphousness in which the flexural modulus (Ua (MPa)) of the resin composition (b) obtained by blending with the homopolypropylene resin (a) measured according to JIS K7203 satisfies the following formula (1). Olefin (co) polymer Ua ≦ 1.5 × Sa × (Ta / 100) ^3.3 (1) (Sa represents the flexural modulus (MPa) measured according to JIS K7203 of (a), and Ta is (Indicates the content (% by weight) of (a) in (b).) (B): thermoplastic resin (however, excluding (A) above). The present invention relates to a foamed molded article comprising the thermoplastic resin composition for foaming. Furthermore, the third invention of the present invention relates to a method for producing a foamed molded product by extrusion molding or injection molding the thermoplastic resin composition for foaming.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The component (A) of the present invention comprises a resin composition (b) obtained by blending with a homopolypropylene resin (a) and a flexural modulus (Ua (MPa) measured in accordance with JIS K7203. )) Is an amorphous olefin (co) polymer satisfying the following formula (1). Ua ≦ 1.5 × Sa × (Ta / 100) ^3.3 (1) (Sa represents a flexural modulus (MPa) measured according to JIS K7203 of (a), and Ta represents (a) in (b). )) (% By weight).)

[0007] As (A), ethylene, having 3 to 2 carbon atoms
And a monomer obtained by (co) polymerizing one or more types of monomers selected from α-olefins, polyene compounds, cyclic olefins, and vinyl aromatic compounds, specifically, ethylene, having 3 to 20 carbon atoms. An α-olefin,
A copolymer obtained by copolymerizing two or more types of monomer components selected from a polyene compound, a cyclic olefin and a vinyl aromatic compound, or a polymer obtained by homopolymerization using these monomers is used as a copolymer. A (co) polymer having a structure corresponding to the polymer is preferable.
Specific examples of monomers constituting such an amorphous olefin (co) polymer include the following monomers (A1) to (A4).

(A1): α-olefin The α-olefin having 3 to 20 carbon atoms includes linear and branched α-olefins. Examples of the linear α-olefin include propylene, 1-butene, 1
-Pentene, 1-hexene, 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-nanodecene, 1-eicosene and the like are exemplified. Examples of the branched α-olefin include 3-methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene, and 2-ethyl. -1-hexene, 2,2
4-trimethyl-1-pentene and the like, and preferably linear propylene, 1-butene, 1-pentene,
-Hexene, 1-octene, 1-decene and the like.

(A2): Polyene Compound The polyene compound includes a so-called conjugated polyene compound in which one single bond is sandwiched between double bonds, and other non-conjugated polyene compounds. Examples of the conjugated polyene compound include an aliphatic conjugated polyene compound and an alicyclic conjugated polyene compound. Examples of the aliphatic conjugated polyene compound include a linear aliphatic conjugated polyene compound and a branched aliphatic conjugated polyene compound. In addition, the aliphatic conjugated polyene compound and the alicyclic conjugated polyene compound may include an alkoxy group, an aryl group, an aryloxy group, an aralkyl group, an aralkyloxy group, and the like. Examples of the aliphatic conjugated polyene compound include 1,3-butadiene, isoprene, 2-ethyl-1,3-butadiene, 2-propyl-1,3-butadiene, 2-isopropyl-1,3-butadiene, Hexyl-1,3-butadiene, 2,3-dimethyl-1,3-butadiene,
2,3-diethyl-1,3-butadiene, 2-methyl-
1,3-pentadiene, 2-methyl-1,3-hexadiene, 2-methyl-1,3-octadiene, 2-methyl-1,3-decadiene, 2,3-dimethyl-1,3-pentadiene, 2, 3-dimethyl-1,3-hexadiene, 2,3-dimethyl-1,3-octadiene, 2,3
-Dimethyl-1,3-decadiene and the like. Examples of the alicyclic conjugated polyene compound include 2-methyl-1,3-cyclopentadiene and 2-methyl-1,3-
Cyclohexadiene, 2,3-dimethyl-1,3-cyclopentadiene, 2,3-dimethyl-1,3-cyclohexadiene, 2-chloro-1,3-butadiene, 2,3
-Dichloro-1,3-butadiene, 1-fluoro-1,
3-butadiene, 2-chloro-1,3-pentadiene,
Examples thereof include 2-chloro-1,3-cyclopentadiene and 2-chloro-1,3-cyclohexadiene.

Examples of the non-conjugated polyene compound include an aliphatic non-conjugated polyene compound, an alicyclic non-conjugated polyene compound, and an aromatic non-conjugated polyene compound. Examples of the aliphatic non-conjugated polyene compound include a linear aliphatic non-conjugated polyene compound and a branched aliphatic non-conjugated polyene compound. Further, the aliphatic non-conjugated polyene compound, the alicyclic non-conjugated polyene compound and the aromatic non-conjugated polyene compound,
It may contain an alkoxy group, an aryl group, an aryloxy group, an aralkyl group, an aralkyloxy group and the like. Examples of the aliphatic non-conjugated polyene compound include 1, 1
4-hexadiene, 1,5-hexadiene, 1,6-heptadiene, 1,6-octadiene, 1,7-octadiene, 1,8-nonadiene, 1,9-decadiene, 1,
13-tetradecadiene, 1,5,9-decatriene,
3-methyl-1,4-hexadiene, 4-methyl-1,
4-hexadiene, 5-methyl-1,4-hexadiene, 4-ethyl-1,4-hexadiene, 3-methyl-
1,5-hexadiene, 3.3-dimethyl-1,4-hexadiene, 3,4-dimethyl-1,5-hexadiene, 5-methyl-1,4-heptadiene, 5-ethyl-
1,4-heptadiene, 5-methyl-1,5-heptadiene, 6-methyl-1,5-heptadiene, 5-ethyl-1,5-heptadiene, 3-methyl-1,6-heptadiene, 4-methyl- 1,6-heptadiene, 4,4-
Dimethyl-1,6-heptadiene, 4-ethyl-1,6
Heptadiene, 4-methyl-1,4-octadiene,
5-methyl-1,4-octadiene, 4-ethyl-1,
4-octadiene, 5-ethyl-1,4-octadiene, 5-methyl-1,5-octadiene, 6-methyl-
1,5-octadiene, 5-ethyl-1,5-octadiene, 6-ethyl-1,5-octadiene, 6-methyl-1,6-octadiene, 7-methyl-1,6-octadiene, 6-ethyl- 1,6-octadiene, 6-propyl-1,6-octadiene, 6-butyl-1.6-octadiene, 4-methyl-1,4-nonadiene, 5-methyl-1,4-nonadiene, 4-ethyl- 1,4-nonadiene, 5-ethyl-1,4-nonadiene, 5-methyl-1,5-nonadiene, 6-methyl-1,5-nonadiene, 5-ethyl-1,5-nonadiene, 6-ethyl-
1,5-nonadiene, 6-methyl-1,6-nonadiene, 7-methyl-1,6-nonadiene, 6-ethyl-
1,6-nonadiene, 7-ethyl-1,6-nonadiene, 7-methyl-1,7-nonadiene, 8-methyl-
1,7-nonadiene, 7-ethyl-1,7-nonadiene, 5-methyl-1,4-decadiene, 5-ethyl-
1,4-decadiene, 5-methyl-1,5-decadiene, 6-methyl-1,5-decadiene, 5-ethyl-
1,5-decadiene, 6-ethyl-1,5-decadiene, 6-methyl-1,6-decadiene, 6-ethyl-
1,6-decadiene, 7-methyl-1,6-decadiene, 7-ethyl-1,6-decadiene, 7-methyl-
1,7-decadiene, 8-methyl-1,7-decadiene, 7-ethyl-1,7-decadiene, 8-ethyl-
1,7-decadiene, 8-methyl-1,8-decadiene, 9-methyl-1,8-decadiene, 8-ethyl-
1,8-decadiene, 6-methyl-1,6-undecadiene, 9-methyl-1,8-undecadiene, 6,10
-Dimethyl 1,5,9-undecatriene, 5,9-dimethyl-1,4,8-decatriene, 4-ethylidene 8
-Methyl-1,7-nonadiene, 13-ethyl-9-methyl-1,9,12-pentadecatriene, 5,9,1
3-trimethyl-1,4,8,12-tetradecadiene, 8,14,16-trimethyl-1,7,14-hexadecatriene, 4-ethylidene-12-methyl-1,
Examples thereof include 11-pentadecadiene. Examples of the alicyclic non-conjugated polyene compound include vinyl cyclohexene, 5-vinyl 2-norbornene, 5-ethylidene-
2-norbornene, 5-methylene-2-norbornene,
5-isopropenyl-2-norbornene, cyclohexadiene, dicyclopentadiene, cyclooctadiene,
2,5-norbornadiene, 2-methyl-2,5-norbornadiene, 2-ethyl-2,5-norbornadiene, 2,3-diisopropylidene-5-norbornene,
2-ethylidene-3-isopropylidene-5-norbornene, 6-chloromethyl-5-isopropylenyl-2-norbornene, 1,4-divinylcyclohexane, 1,3
-Divinylcyclohexane, 1,3-divinylcyclopentane, 1,5-divinylcyclooctane, 1-allyl-4-vinylcyclohexane, 1,4-diallylcyclohexane, 1-allyl-5-vinylcyclooctane,
1,5-diallylcyclooctane, 1-allyl-4-isopropenylcyclohexane, 1-isopropenyl-4
-Vinylcyclohexane, 1-isopropenyl-3-vinylcyclopentane, methyltetrahydroindene and the like. Examples of the aromatic non-conjugated polyene compound include divinylbenzene and vinylisopropenylbenzene.

(A3): Cyclic olefin compound As the cyclic olefin, for example, norbornene, 5
-Methylnorbornene, 5-ethylnorbornene, 5-
Propyl norbornene, 5,6-dimethylnorbornene, 1-methylnorbornene, 7-methylnorbornene, 5,5,6-trimethylnorbornene, 5-phenylnorbornene, 5-benzylnorbornene, 5-ethylidenenorbornene, 5-vinylnorbornene, ,
4,5,8-Dimethano-1,2,3,4,4a, 5
8,8a-octahydronaphthalene, 2-methyl-1,
4,5,8-Dimethano-1,2,3,4,4a, 5
8,8a-octahydronaphthalene, 2-ethyl-1,
4,5,8-Dimethano-1,2,3,4,4a, 5
8,8a-octahydronaphthalene, 2,3-dimethyl-1,4,5,8-dimethano-1,2,3,4,4a,
5,8,8a-octahydronaphthalene, 2-hexyl-1,4,5,8-dimethano-1,2,3,4,4a,
5,8,8a-octahydronaphthalene, 2-ethylidene-1,4,5,8-dimethano-1,2,3,4,4
a, 5,8,8a-octahydronaphthalene, 2-fluoro-1,4,5,8-dimethano-1,2,3,4,4
a, 5,8,8a-octahydronaphthalene, 1,5-
Dimethyl-1,4,5,8-dimethano-1,2,3
4,4a, 5,8,8a-octahydronaphthalene, 2
-Cyclohexyl-1,4,5,8-dimethano-1,
2,3,4,4a, 5,8,8a-octahydronaphthalene, 2,3-dichloro-1,4,5,8-dimethano-
1,2,3,4,4a, 5,8,8a-octahydronaphthalene, 2-isobutyl-1,4,5,8-dimethano-1,2,3,4,4a, 5,8,8a- Octahydronaphthalene, 1,2-dihydrodicyclopentadiene,
5-chloronorbornene, 5,5-dichloronorbornene, 5-fluoronorbornene, 5,5,6-trifluoro-6-trifluoromethylnorbornene, 5-chloromethylnorbornene, 5-methoxynorbornene,
5,6-dicarboxyl norbornene anhydrate, 5-dimethylamino norbornene, 5-cyanonorbornene, cyclopentene, 3-methylcyclopentene, 4-methylcyclopentene, 3,4-dimethylcyclopentene, 3,5-dimethylcyclopentene, 3- Chlorocyclopentene, cyclohexene, 3-methylcyclohexene, 4-methylcyclohexene, 3,4-dimethylcyclohexene, 3-chlorocyclohexene, cycloheptene and the like are exemplified.

(A4): Vinyl aromatic compound Examples of the vinyl aromatic compound include styrene and α-
Methyl styrene, p-methyl styrene, vinyl xylene, monochlorostyrene, dichlorostyrene, monobromostyrene, dibromostyrene, fluorostyrene, p
-Tert-butylstyrene, ethylstyrene, vinylnaphthalene and the like.

Further, in the present invention, from the viewpoint of achieving flexibility, which is one of the objects of the present invention, an amorphous olefin-based copolymer comprising a combination of specific monomers selected from the above-mentioned monomers is preferred. Polymers are preferred, and examples of such preferred amorphous olefin-based copolymers include the following combinations (a) to (z). (A): Non-ethylene obtained by copolymerizing at least one monomer component selected from a polyene compound, a cyclic olefin and a vinyl aromatic compound, which essentially comprises ethylene and an α-olefin having 3 to 20 carbon atoms. Crystalline olefin copolymer (b): Essentially ethylene and an α-olefin having 4 to 20 carbon atoms, optionally copolymerizing at least one monomer component selected from a polyene compound, a cyclic olefin and a vinyl aromatic compound Amorphous olefin copolymer obtained by polymerization (C): Ethylene, propylene and α-olefin having 4 to 20 carbon atoms as essential components, optionally selected from polyene compounds, cyclic olefins and vinyl aromatic compounds Amorphous olefin-based copolymer obtained by copolymerizing one or more types of monomer components to be used (d): propylene and carbon Amorphous olefin copolymer obtained by copolymerizing at least one kind of monomer component selected from a polyene compound, a cyclic olefin and a vinyl aromatic compound with α-olefin of Formulas 4 to 20 as an essential component (E): Amorphous olefin copolymer composed of ethylene, an α-olefin having 4 to 20 carbon atoms (f): Amorphous olefin copolymer composed of ethylene, an α-olefin having 4 to 20 carbon atoms and a polyene compound Copolymer (g): Amorphous olefin copolymer composed of ethylene, α-olefin having 4 to 20 carbon atoms and cyclic olefin compound (H): ethylene, α-olefin having 4 to 20 carbon atoms and vinyl aromatic Amorphous olefin-based copolymer comprising a group III compound (i): ethylene, an α-olefin having 4 to 20 carbon atoms,
Amorphous olefin copolymer composed of polyene compound and vinyl aromatic compound (nu): ethylene, propylene, α- having 4 to 20 carbon atoms
Amorphous olefin copolymer composed of olefin (R): ethylene, propylene, α- having 4 to 20 carbon atoms
Amorphous olefin copolymer composed of olefin and polyene compound (E): ethylene, propylene, α- having 4 to 20 carbon atoms
Amorphous olefin copolymer composed of olefin and cyclic olefin compound (W): ethylene, propylene, α- having 4 to 20 carbon atoms
Amorphous olefin copolymer composed of olefin and vinyl aromatic compound (f): ethylene, propylene, α- having 4 to 20 carbon atoms
Olefin copolymer comprising olefin, polyene compound and vinyl aromatic compound (Y): Amorphous olefin copolymer obtained by copolymerizing propylene and an α-olefin having 4 to 20 carbon atoms (T): Amorphous olefin copolymer composed of propylene, an α-olefin having 4 to 20 carbon atoms and a polyene compound (f): Amorphous olefin copolymer composed of propylene, an α-olefin having 4 to 20 carbon atoms and a cyclic olefin compound Copolymer (so): Amorphous olefin copolymer composed of propylene, α-olefin having 4 to 20 carbon atoms and vinyl aromatic compound (T): propylene, α-olefin having 4 to 20 carbon atoms, polyene Olefinic Copolymer Consisting of Compound and Vinyl Aromatic Compound

Among these, (b) and (c) are particularly preferable from the viewpoint of the cold resistance of the obtained foamed molded article. (A) preferably satisfies the following relational expression. x ≦ 70− (0.5 × y) More preferably x ≦ 65− (0.5 × y) More preferably x ≦ 60− (0.5 × y) Most preferably x ≦ 55− (0.5 × y). Here, x and y in the formula are ethylene mole content (x) in the total amount of ethylene, propylene, and a repeating unit of an α-olefin having 4 to 20 carbon atoms contained in (A).
%) And the propylene molar content (y%). If the ratio is outside the above range, the flexibility of the foamed molded article may be poor.

(A) is a combination of (A2), (A3) and (A
When (4) is included, it occupies (A2) and (A3) in (A).
The total amount of (A4) and (A4) is preferably at most 30 mol%, more preferably at most 25 mol%, further preferably at most 20 mol%, particularly preferably at most 15 mol%. If the ratio is outside the above range, the flexibility of the foam molded article may be poor.

In (A), the tensile strength at break measured according to JIS K6251 is preferably less than 2.0 MPa, more preferably less than 1.8 MPa.
More preferably less than 1.6 MPa, more preferably less than 1.4 MPa, and even more preferably 1.2 MPa
a, more preferably less than 1.0 MPa, particularly preferably less than 0.8 MPa. Outside the range, the flexibility of the foamed molded article may be poor.

(A) needs to be amorphous. Here, the term “amorphous” means that a differential scanning calorimeter (DSC) is used.
When measured in accordance with JIS K 7122, it means that it has neither a peak of 1 J / g or more based on melting of the crystal nor a peak of 1 J / g or more based on crystallization. If it is not amorphous, the foamed article is inferior in flexibility.
A differential scanning calorimeter is manufactured by Seiko Electronics Industries, Ltd.
SC220C was used for both the temperature raising and the constant temperature process.
The measurement is performed at a rate of ° C./min.

(A) shows the molecular weight distribution (M) measured by gel permeation chromatography (GPC).
(w / Mn) is preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less. If the molecular weight distribution is too wide, the flexibility of the foamed molded article may be inferior, and the wide molecular weight distribution of the polymer obtained by one-pot polymerization generally means that the intermolecular composition distribution is wide, In such a case, there is a high possibility that the surface properties of the foamed molded article with time will deteriorate. The molecular weight distribution is determined by gel permeation chromatography (GPC) (for example, Wa
ters, 150C / GPC device). The elution temperature is 140 ° C., and the column used is, for example, Sodex Packed Column A-80 manufactured by Showa Denko KK
M, a polystyrene (for example, a molecular weight of 68-8, 400,000, manufactured by Tosoh Corporation) is used as a molecular weight standard substance. The obtained polystyrene-equivalent weight average molecular weight (Mw), number average molecular weight (Mn), and the ratio (Mw / Mn) are defined as a molecular weight distribution. Measurement sample is about 5mg of polymer 5ml
Dissolved in o-dichlorobenzene at a concentration of about 1 mg / ml. 400 μl of the obtained sample solution was injected, the elution solvent flow rate was set to 1.0 ml / min,
Detect with a refractive index detector.

In (A), the intrinsic viscosity [η] of a tetralin solvent at a temperature of 135 ° C. is preferably 0.3 to 1
0.0, more preferably 0.5 to 7.0,
More preferably, it is 0.7 to 5.0. If the intrinsic viscosity is too low, the heat resistance of the foam molded article may be poor. On the other hand, if the intrinsic viscosity is too high, the resulting foamed molded article may have poor flexibility. The measurement of the intrinsic viscosity [η] is 13
Performed in 5 ° C. tetralin using an Ubbelohde viscometer. Sample dissolved 300mg in 100ml tetralin,
A 3 mg / ml solution was prepared. The solution was further diluted with 1 /
Dilute to 2, 1/3 and 1/5, each at 135 ° C (±
(0.1 ° C) in a constant temperature oil bath. The measurement is repeated three times at each concentration, and the obtained values are averaged and used.

(A) is a homopolypropylene resin (a)
JIS K of resin composition (b) obtained by blending with
Flexural modulus (Ua (MP
a)) must satisfy the following expression (1). Ua ≦ 1.5 × Sa × (Ta / 100) ^3.3 (1) (Sa represents a flexural modulus (MPa) measured according to JIS K7203 of (a), and Ta represents (a) in (b). )) (% By weight).) More preferably, Ua ≦ 1.4 × Sa × (Ta / 100) ^3.3 More preferably, Ua ≦ 1.3 × Sa × (Ta / 100) ^3.3 Particularly preferably, Ua ≦ 1.2 × Sa × (Ta / 100) ^3.3 . When the ratio is outside the above range, the flexibility of the obtained foamed molded article is poor, and a good foamed molded article cannot be obtained.

In the above, (a) is 70 to 30% by weight
It is preferable to use a thermoplastic resin composition in which (A) is 30 to 70% by weight. As the index of crystallinity of (a), for example, JIS K 7121 and JIS K
The melting point, crystal melting calorie and the like measured using a differential scanning calorimeter (DSC) according to 7122 are used.
° C to 176 ° C, the heat of crystal fusion is 60 J / g to 120 J /
g, the melting point is in the range of 145 ° C. to 176 ° C., and the heat of crystal fusion is in the range of 70 J / g to 120 J / g.
Further, the melting point is 150 ° C. to 176 ° C., and the heat of crystal fusion is 8
The range is from 0 J / g to 120 J / g. The method for producing (a) includes a Ziegler-Natta type catalyst using a combination of a so-called titanium-containing solid transition metal component and an organometallic component, or Group 4 of the periodic table having at least one cyclopentadienyl skeleton. Obtained by homopolymerizing propylene using a metallocene catalyst composed of a transition metal compound of Group 1 to Group 6 and a cocatalyst component, by slurry polymerization, gas phase polymerization, bulk polymerization, solution polymerization, or a combination thereof. There are things. In addition, it is also possible to use a corresponding product on the market.

(A) can be produced using a known Ziegler-Natta type catalyst or a known single-site catalyst (metallocene or the like), but from the viewpoint of the uniformity of the composition distribution of the obtained polymer. Known single-site catalysts (such as metallocene catalysts) are preferred. Examples of such single-site catalysts include, for example, JP-A-58-1930.
No. 9, JP-A-60-35005, JP-A-60-60
JP-A-350006, JP-A-60-35007,
JP-A-60-35008, JP-A-61-1303
No. 14, JP-A-3-1630088, JP-A-4
-268307, JP-A-9-12790,
JP-A-9-87313, JP-A-10-50805
No. 5, JP-A-11-80233, JP-T-Hei10
Metallocene catalysts described in JP-A-505085 and the like, JP-A-10-316710, JP-A-11-1003
No. 94, JP-A-11-80228, JP-A-1
JP-A-1-80227, JP-A-10-513489, JP-A-10-338706, JP-A-11-11-7
Non-metallocene complex catalysts described in No. 1420 can be exemplified. Among them, metallocene catalysts are generally used. Among them, examples of suitable metallocene catalysts include a cyclopentadiene-type anion skeleton. From the viewpoint of the flexibility of the obtained polymer having at least one, transition metal complexes of Groups 3 to 12 of the periodic table having a C ₁ symmetric structure are preferred. Further, as an example of a suitable production method using a metallocene catalyst for obtaining a polymer having a high molecular weight, a production method exemplified as a suitable production method in Japanese Patent Application No. 11-206054 can be exemplified.

The component (B) of the present invention is a thermoplastic resin (excluding the above (A)) and can be selected from a wide variety of known thermoplastic resins. Polypropylene resin, poly (butene-1) resin, poly (4-methylpentene-1) resin, thermoplastic elastomer resin, polystyrene resin, polyvinyl chloride resin, polyamide resin, polycarbonate resin And various thermoplastic resins such as polyethylene terephthalate-based resins, PMMA-based resins, ABS-based resins and the like, modified products thereof, polymer alloys, and mixtures thereof. One or more of these may be used.

(B) includes polyethylene resins such as high-density polyethylene, medium-density polyethylene, low-density polyethylene, linear low-density polyethylene (LLDPE), polypropylene resins, polybutene resins, and poly-4- A polyolefin resin (B-1) such as a methyl-pentene-1 resin is preferred, and a polyolefin resin (B-
2), and more preferably, a crystalline polyolefin-based resin (B
-3), and particularly preferably a crystalline polypropylene resin (B-4).

(B-4) is a crystalline polypropylene mainly having an isotactic or syndiotactic sequence structure, and has a wide range of structures such as a homo-type or a random type containing a comonomer, or a block type by multi-stage polymerization. Are available.
In addition, the polypropylene-based resin can employ a gas-phase polymerization method, a bulk polymerization method, a solvent polymerization method and optionally a multi-stage polymerization by combining them, and the number average molecular weight of the polymer is not particularly limited. But preferably 10,0
It is adjusted to 00 to 1,000,000.

As the index of the crystallinity of (B-4), for example, a melting point, a heat of crystal fusion and the like are used.
° C to 176 ° C, the heat of crystal fusion is 30 J / g to 120 J /
It is preferably in the range of g. Furthermore, the melting point is 120
° C to 176 ° C, the heat of crystal fusion is 60 J / g to 120 J /
It is preferably in the range of g. If the melting point of the crystal is too low or the heat of fusion is too low, the heat resistance of the obtained foamed molded article may decrease.

As a method for producing (B-4), generally, a Ziegler-Natta type catalyst using a combination of a so-called titanium-containing solid transition metal component and an organic metal component, or at least a cyclopentadienyl skeleton is used. Slurry polymerization, gas phase polymerization, bulk polymerization, solution polymerization, or the like, or a polymerization method combining these, using a metallocene catalyst comprising a transition metal compound of Groups 4 to 6 of the periodic table having one and a cocatalyst component. In one step or multiple steps, a homopolymer is obtained by homopolymerizing propylene, or propylene and one or more olefins selected from other olefins having 2 to 12 carbon atoms are copolymerized in one step or multiple steps. To obtain a copolymer. In addition, it is also possible to use a corresponding product on the market.

When the foamed molded article of the present invention is required to have excellent performance in flexibility, heat resistance and impact resistance, (B)
Polypropylene resin composition (B) obtained by copolymerizing ethylene and propylene in two or more stages
-5) is preferable. More specifically, (B-
5) In the first step, a propylene homopolymer or an ethylene-propylene copolymer having an ethylene content of 5.0% by weight or less is obtained, and an ethylene-propylene copolymer having an ethylene content of 7 to 85% by weight is obtained in the second and subsequent steps. A propylene copolymer is obtained, and the weight ratio of the polymer obtained in the first stage to the polymer obtained in the second and subsequent stages is 30/70 to 90/10. (Hereinafter, the propylene homopolymer or ethylene-propylene copolymer obtained in the first stage polymerization may be referred to as “copolymer-1”. In addition, ethylene obtained in the second and subsequent stages of copolymerization may be referred to as “copolymer-1”. -The propylene copolymer may be referred to as "copolymer-2".)

The ethylene content of the copolymer-1 is preferably not more than 5.0% by weight. The ethylene content is 5.
If it exceeds 0% by weight, the heat resistance of the foamed molded article obtained using the polypropylene resin composition may be poor.

The ethylene content of the copolymer-2 is from 7 to 85.
% By weight. If the ethylene content is too low, the flexibility and impact resistance of the foamed molded article obtained using the polypropylene resin composition may be poor, while if the ethylene content is too high, the polypropylene resin In some cases, the impact resistance of a foam molded article obtained using the composition may be reduced.

The weight ratio of copolymer-1 to copolymer-2 is 3
0/70 to 90/10. If the amount of copolymer-1 is too small (the amount of copolymer-2 is too large), the foamed article obtained by using the polypropylene resin composition may not be able to obtain sufficient heat resistance. If the amount of the polymer-1 is too large (the amount of the copolymer-2 is too small), the impact resistance of the foamed molded article obtained by using the polypropylene resin composition may not be sufficient.

Incidentally, the copolymer-1 and the copolymer-2 are
It may be one containing one or more α-olefins other than propylene and ethylene (eg, butene-1, hexene-1, octene-1, etc.) in a small amount, for example, about 1 to 5% by weight.

As the above polypropylene resin,
Sometimes referred to as "block polypropylene" or "high-impact polypropylene", commercially available products can be used.

The foaming thermoplastic resin composition of the present invention comprises:
The weight ratio of (A) / (B) is from 5/95 to 95/5, preferably from 30/70 to 94/6, more preferably from 40/60 to 93/7, and still more preferably. Is 50/50 to 92/8. If the ratio is too small, the flexibility is inferior. On the other hand, if the ratio is too large, the heat resistance is reduced and the range of molding conditions for obtaining a good product is narrowed.

[0035] The thermoplastic resin composition for foaming of the present invention preferably has a Shore A hardness of 95 or less, more preferably 90 or less, even more preferably 85 or less.
It is particularly preferably at most 80, most preferably at most 75.

The thermoplastic resin composition for foaming of the present invention may contain, in addition to the essential components (A) and (B), one or more components selected from the following. : Block copolymer composed of a polymer block mainly composed of a vinyl aromatic compound and a polymer block mainly composed of a conjugated diene compound: Hydrogenated product of: Tensile cut strength measured in accordance with JIS K6251 Polymer having a viscosity of 2.0 MPa or more: thermoplastic elastomer

Is a block copolymer comprising a polymer block mainly composed of a vinyl aromatic compound and a polymer block mainly composed of a conjugated diene compound. The polymer block mainly composed of a vinyl aromatic compound is a polymer block mainly containing a vinyl aromatic compound and also containing a conjugated diene compound or the like as another component.
As the vinyl aromatic compound, styrene, α-methylstyrene, p-methylstyrene, vinylxylene, monochlorostyrene, dichlorostyrene, monobromostyrene,
Dibromostyrene, fluorostyrene, p-tert-
Butyl styrene, ethyl styrene, vinyl naphthalene and the like can be mentioned. These may be used alone or in combination of two or more. Of these, particularly preferred is styrene. The content of the vinyl aromatic compound in the polymer block is preferably from 60 to 99% by weight. If the content is too small, the mechanical strength of the foamed molded article may be poor. On the other hand, if the content is excessive, the flexibility of the foamed molded article may be poor.

The polymer block mainly containing a conjugated diene compound is a polymer block mainly containing a conjugated diene compound and also containing a vinyl aromatic compound or the like as another component. 1,3 as conjugated diene compounds
-Butadiene, isoprene, 2,3-dimethyl-1,3
-Butadiene, 2-neopentyl-1,3-butadiene, 2-chloro-1,3-butadiene, 2-cyano-
Examples include 1,3-butadiene, substituted linear conjugated pentadienes, linear and side chain conjugated hexadienes. These may be used alone or in combination of two or more. Of these, particularly preferred are 1,3-butadiene and isoprene. The content of the conjugated diene compound in the polymer block is preferably from 60 to 99% by weight. If the content is too small, the flexibility of the foamed molded article may be poor. On the other hand, if the content is excessive, the mechanical strength of the foamed molded article may be poor.

Is a compound represented by the general formula: (cH-cS)
n, (cH-cS) n-cH, (cH-cS) n-X
(In the formula, cH is a polymer block mainly composed of a vinyl aromatic compound, cS is a polymer block mainly composed of a conjugated diene compound, X is a residue of a coupling agent, and n is an integer of 1 or more.) expressed.

A block copolymer composed of a polymer block mainly composed of a vinyl aromatic compound and a polymer block mainly composed of a conjugated diene compound is mainly composed of a polymer block mainly composed of a vinyl aromatic compound and a polymer block mainly composed of a conjugated diene compound. The content ratio of the polymer block to be used is 2/98 to 50 /
Preferably it is 50. If the ratio is too low, the elasticity of the foam molded article is low, and high elasticity may not be obtained,
On the other hand, if the ratio is excessive, the flexibility of the foamed molded article may be poor.

For example, the block cH or block cS may be first polymerized in an organic solvent using a polymerization initiator such as an organic lithium compound, and then the block cS or block cH may be polymerized. . Either block cH or block cS may be polymerized first. Further, by repeating these operations, (cH-c
S) n-block copolymer (n is an integer of 1 or more)
You can also get Further, in an organic solvent, using a polymerization initiator such as an organic lithium compound, the block cH is polymerized, the block cS is further polymerized, and the block cH is further polymerized, whereby the cH-cS-cH block copolymerization is performed. Coalescence can be obtained. By repeating these operations,
(CH-cS) n-cS block copolymer (n is an integer of 1 or more) can also be obtained. By adding a coupling agent to the (cH-cS) n block copolymer thus obtained, (cH-cS) n-X
A block copolymer (X is a residue of a coupling agent, and n is an integer of 1 or more) can also be obtained. As coupling agents, diethyl adipate, divinylbenzene,
Tetrachlorosilane, butyltrichlorosilane, tetrachlorotin, butyltrichlorotin, dimethyldichlorosilane, tetrachlorogermanium, 1,2-dibromoethane, 1,4-chloromethylbenzene, bis (trichlorosilyl) ethane, epoxidized linseed oil, Tolylene diisocyanate, 1,2,4-benzene triisocyanate and the like can be mentioned. As a block copolymer composed of a polymer block mainly composed of a vinyl aromatic compound and a polymer block mainly composed of a conjugated diene compound, a corresponding commercially available product can also be used.

Is the above hydrogenated product. To obtain, for example, the above is dissolved in an inert solvent,
Hydrogenation may be carried out at 20 to 150 ° C. and 1 to 100 kg / cm ² G under pressurized hydrogen in the presence of a hydrogenation catalyst. The hydrogenation rate of the conjugated diene compound in the above is adjusted by changing the amount of the hydrogenation catalyst and the hydrogenated compound, or the hydrogen pressure and the reaction time during the hydrogenation reaction.
As the above-mentioned hydrogenated product, a corresponding commercially available product can also be used.

When the foamed molded article of the present invention is required to have excellent performance in flexibility and heat resistance, in addition to the predetermined amounts of the essential components (A) and (B), and / or It is preferable to use an amount of 5 to 95% by weight, preferably 30 to 94% by weight, more preferably 40 to 93% by weight, still more preferably 50 to 92% by weight. The mixing ratio of (A) and / or is not particularly limited, but from the viewpoint of weather resistance and moldability, the amount of (A) in the total amount of (A) and / or 30% by weight or more. , More preferably 40% by weight or more, even more preferably 5% by weight or more.
0% by weight or more.

Is an ethylene polymer having a tensile strength at break of 2.0 MPa or more measured in accordance with JIS K6251. Specific examples of low-density polyethylene, linear low-density polyethylene, ultra-low-density polyethylene,
Medium-density polyethylene, high-density polyethylene and copolymers containing ethylene, ie, ethylene and propylene,
-Butene, 4-methyl-1-pentene, 1-hexene,
Α-olefins such as 1-heptene and 1-octene;
Non-conjugated dienes such as 4-hexadiene, dicyclopentadiene and 5-ethylidene-2-norbornene, monocarboxylic acids such as acrylic acid, methacrylic acid, ethacrylic acid and crotonic acid, maleic acid, fumaric acid, itaconic acid and citraconic acid A dicarboxylic acid or a monoester thereof, methyl methacrylate, methyl acrylate, acrylic acid or methacrylic acid ester such as ethyl acrylate, vinyl acetate, a vinyl ester of a saturated carboxylic acid such as vinyl propionate and one selected from ionomers thereof,
Copolymers or multi-component copolymers with two or more comonomers can be exemplified. These polymers or copolymers may be a mixture of two or more. Further preferably, an ethylene polymer having an ethylene content of 80 mol% or more is used.

When the foamed molded article of the present invention is required to have excellent low-temperature resistance, in addition to the prescribed amounts of the essential components (A) and (B), the total amount of (A) Is 5-9
5% by weight, preferably 30 to 94% by weight, more preferably 40 to 93% by weight, still more preferably 50 to 92% by weight
Is preferable. The mixing ratio with (A) is not particularly limited.

When the thermoplastic resin composition for foaming of the present invention is required to have excellent properties such as flexibility, mechanical strength and low-temperature resistance, a predetermined amount of the essential components (A) and (B) is required. And the total amount of (A) and / or
It is preferable to contain 95% by weight, preferably 30 to 94% by weight, more preferably 40 to 93% by weight, and still more preferably 50 to 92% by weight. The mixing ratio of (A) and / or is not particularly limited.

Can be selected from a wide range of known thermoplastic elastomers, for example, olefin-based thermoplastic elastomers, styrene-based thermoplastic elastomers,
Vinyl chloride thermoplastic elastomer, urethane thermoplastic elastomer, ester thermoplastic elastomer, amide thermoplastic elastomer, chlorinated polyethylene thermoplastic elastomer, Syn-1,2-polybutadiene thermoplastic elastomer, Trans-1,4 poly Examples include isoprene thermoplastic elastomers and fluorine-based thermoplastic elastomers.

The thermoplastic resin composition for foaming of the present invention comprises:
In addition to the essential components (A) and (B), if necessary, an amorphous component other than (A), for example, natural rubber, polybutadiene, liquid polybutadiene, polyacrylonitrile rubber, acrylonitrile-butadiene copolymer Rubber, partially hydrogenated acrylonitrile-butadiene copolymer rubber, butyl rubber, chloroprene rubber, fluorine rubber, chlorosulfonated polyethylene, silicon rubber, urethane rubber, isobutylene-isoprene copolymer rubber, halogenated isobutylene-isoprene copolymer rubber, etc. Can be appropriately blended.

The thermoplastic resin composition for foaming of the present invention can be obtained by mixing using a known mixing device, for example, a Banbury mixer, an extruder or the like. Further, the respective components can be mixed in a pellet state without melting, and used for molding.

In order to decorate the appearance of the foam molded article,
If necessary, additives such as a glitter filler, a pigment for coloring, an inorganic filler, an antistatic agent, an antioxidant, a nucleating agent, a plasticizer, and an antibacterial agent may be added in an appropriate amount.

The foamed molded article of the present invention has an expansion ratio of 1.2.
It is preferably at least two times. If the expansion ratio is 1.2 times or less, it is difficult to obtain a sufficiently soft touch.

The foamed molded article of the present invention is prepared by molding the thermoplastic resin composition for foaming by various molding methods such as extrusion molding, injection molding, injection compression molding, injection press molding, injection blow molding, blow molding, and mold molding. Thus, a foam molded article can be obtained.

In particular, a mixture of the thermoplastic resin composition for foaming of the present invention and a pyrolytic foaming agent is used as a material input port (hopper).
Into the extruder to cause melting of the resin and generation of gas due to decomposition of the foaming agent. The molten resin and the gas are sufficiently kneaded and homogenized, and the homogenized mixture is heated to a temperature suitable for foaming. After the mixture is cooled to, the mixture is extruded from a die and foamed, cooled by a take-off machine, and molded into a foamed molded article. The foamed molded article of the present invention can be used in the extrusion molding method.

There is no particular limitation on the extruder used for the production of the foamed molded article by the extrusion molding method. At least, the resin and the foaming gas can be sufficiently kneaded and homogenized, and cooled and adjusted to a temperature suitable for foaming. Any extruder may be used, and examples of such an extruder include a single-screw extruder and a multi-screw extruder. Generally, a twin screw extruder is used as the multi-screw extruder, and the screw may be rotated in the same direction or in different directions. Regarding the type of the twin-screw extruder, a parallel twin-screw extruder in which the diameter of the screw is constant or an oblique twin-screw extruder in which the tip of the screw has a small diameter may be used. In the case of a twin-screw extruder, a sealing segment is preferably provided on the screw because the foaming gas easily escapes from the hopper. The single-screw extruder is low in cost because foaming gas is less likely to escape from the hopper,
It is preferably used. It is also possible to use a tandem extruder in which a single-screw extruder and a multi-screw extruder are combined. As the die of the extruder, a flat die or a circular die can be used, and the thickness of the foam molded article can be controlled by adjusting the lip gap at the tip of the die.

As another production method, a mixture of the thermoplastic resin composition for foaming of the present invention and a pyrolytic foaming agent is charged into a raw material charging port (hopper) to melt the resin and decompose the foaming agent in a cylinder. Gas is generated, and the molten resin and gas are sufficiently kneaded and homogenized.After injecting the homogenized mixture into the mold cavity, while cooling to a temperature suitable for foaming, The foam molded article of the present invention can be obtained by an injection molding method for expanding the volume of the cavity.

The foaming agent used in the present invention is not particularly limited, and may be a physical foaming agent represented by carbon dioxide, nitrogen gas, butane, etc., a chemical foaming agent represented by baking soda, azodicarboxylic acid amide, etc. And these can be used in combination. In addition, an inorganic filler such as talc or silica can be added as a cell nucleating agent.

Volatile organic solvents such as butane and pentane have high solubility in resin and easily reduce bubble growth in a die, but there is a risk of fire and explosion in the manufacturing process. In the case of a fluorocarbon compound, there is no danger of explosion and high solubility, but there are environmental problems such as destruction of the ozone layer.

In the case of a chemical foaming agent, since the foam has a decomposition residue of the foaming agent, discoloration of the foam, generation of odor, and the like may be a concern depending on the application.

That is, nitrogen, carbon dioxide gas,
It is preferable to use an inorganic gas such as air, but the solubility in the resin is lower than that of a solvent, chlorofluorocarbon or the like, and bubbles easily grow in the die. However, among inorganic gases, carbon dioxide is highly soluble and is particularly suitable.

As the foaming agent used in the present invention, examples of the pyrolysis type which decomposes upon heating to generate a gas include azodicarbonamide, oxybenzenesulfonylhydrazide, azobisbisbutyronitrile, and azodicarboxylic acid. Barium, hydrazodicarbonamide and the like can be mentioned. Further, in order to obtain a foamed molded article of a thermoplastic resin having uniform cells, it is necessary to set the decomposition temperature of the foaming agent to around the melting point of the thermoplastic resin composition for foaming,
A foaming aid for adjusting the decomposition temperature of the foaming agent may be added. The amount of the foaming agent to be added is not particularly limited as long as the required amount of gas is generated. Furthermore, in order to prevent generation of non-uniform bubbles due to heat generated during decomposition of the foaming agent, a foaming agent exhibiting an endothermic decomposition behavior may be used in combination.

As the gas for foaming used in the present invention, an inert gas such as nitrogen gas or carbon dioxide gas may be used instead of the pyrolytic foaming agent (the inert gas is directly injected into the molding machine). Alternatively, a pyrolytic foaming agent and an inert gas may be used in combination.

From the viewpoint of obtaining a foam molded article having a fine cell diameter, it is preferable to use a mixed gas of nitrogen gas and carbon dioxide gas as the foaming gas. In this case, for example, a mixed gas of nitrogen gas and carbon dioxide gas is used. Examples of the method include directly injecting a mixed gas into an extruder, and a method using a pyrolytic foaming agent that mainly generates nitrogen gas by decomposition and a pyrolytic foaming agent that mainly generates carbon dioxide gas by decomposition. it can. When two or more thermal decomposition type foaming agents are used in combination, these foaming agents may be used separately, or a foaming agent (composite foaming agent) obtained by mixing these foaming agents in advance may be used. As the composite foaming agent, a composite foaming agent comprising a pyrolytic foaming agent that mainly generates nitrogen gas and a pyrolytic foaming agent that mainly generates carbon dioxide gas is preferable.

As the pyrolytic foaming agent mainly generating nitrogen gas, azodicarbonamide, azobisisobutyronitrile, dinitrosopentamethylenetetramine, p-
Examples include toluenesulfonyl hydrazide and p, p'-oxy-bis (benzenesulfonyl hydrazide), and azodicarbonamide is preferred. These foaming agents may be used in combination.

Examples of the pyrolytic blowing agent that mainly generates carbon dioxide gas include sodium bicarbonate, ammonium carbonate and ammonium bicarbonate, and sodium bicarbonate is preferred. These foaming agents may be used in combination.

As the foaming agent, a foaming agent and a foaming auxiliary may be used in combination, if necessary. Examples of the foaming aid include zinc oxide, zinc nitrate, basic zinc carbonate, zinc stearate, lead phthalate, lead carbonate, urea, and glycerin. It is also preferable to use a powder of calcium carbonate, talc, silica or the like as a foam nucleating agent in combination.

When a thermally decomposable organic foaming agent which mainly generates nitrogen gas and a pyrolyzable inorganic foaming agent which mainly generates carbon dioxide gas are used in combination, the weight ratio of the former foaming agent to the latter foaming agent is as follows: From the viewpoint that the bubble diameter is fine and uniform, 1 /
99-30 / 70, preferably 1 / 99-20 / 80,
More preferably, it is 1/99 to 10/90.

When a mixed gas of nitrogen gas and carbon dioxide is used as the foaming agent, the volume ratio of nitrogen gas to carbon dioxide is 1/99 to 30/70, preferably 1/99 to 20/8.
0, more preferably 1/99 to 10/90. In this case, it is preferable to use a powder of calcium carbonate, talc, silica or the like as a foam nucleating agent.

The foam molded article of the present invention may be crosslinked or non-crosslinked.

The foamed molded article according to the present invention can be used for automobile interior parts such as instrument panels, door trims, console boxes, etc., automobile exterior parts such as weather strip sponges, body panels, side moldings, etc .; Sealing materials for the purpose of soundproofing, dustproofing, heat insulation, etc., footwear such as shoe soles and sandals, electric appliances such as VTR cameras, various household goods and the like are included.

[0070]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but these examples do not limit the present invention in any way. The analytical values in the examples were obtained by the following methods. Melt index (MI) In accordance with JIS K7210, a resin having a repeating unit derived from propylene as a main component has a temperature of 2
The measurement was carried out at 30 ° C. and a load of 2.16 kgf, and the resin having a repeating unit derived from ethylene as a main component was measured at a temperature of 190 ° C. and a load of 2.16 kgf. Crystallization temperature The crystallization temperature (Tc) and the melting point (Tm) were measured using DSC (DSC220, manufactured by Seiko Denshi). The measurement conditions were as follows: first, the temperature was raised from 20 ° C. to 260 ° C. at a rate of 20 ° C./min, held for 2 minutes, then lowered from 260 ° C. to −50 ° C. at a rate of 5 ° C./min, and the crystallization temperature was measured. . Further, the temperature was raised from −50 ° C. to 260 ° C. at a rate of 20 ° C./min, and the melting point was determined.

Reference Example 1 Synthesis of Amorphous Olefinic Copolymer (A) (1) Triisobutylaluminum
(2) N, N-dimethylanilinium tetrakis (pentafluoro) phenyl borate, (3) dimethylsilyl (tetramethylcyclopentadienyl) (3-tert
Using -butyl-5-methyl-2-phenoxy) titanium dichloride, ethylene, propylene and 1-butene were copolymerized. (1), (2) and (3) were used in a molar ratio of 633: 28: 1. The polymerization temperature was 50 ° C., the polymerization pressure was 7.8 MPa, and hexane was used as a polymerization solvent and a catalyst adjusting solvent. The obtained ethylene-propylene-
50% by weight of 1-butene copolymer and JIS K7203
The flexural modulus measured in accordance with
a) is a homopolypropylene (manufactured by Sumitomo Chemical Co., Ltd.)
Product name Sumitomo Noblen Y101C (MFR (230
C., 2.16 kg load) = 12.5 g / 10 min) JIS K720 of a resin composition mixed at 50% by weight (Ta).
The flexural modulus measured in accordance with No. 3 is 117 MPa (U
a), and it was confirmed that the ethylene-propylene-1-butene copolymer satisfied the requirements of the following relational expression. Ua ≦ 1.5 × Sa × (Ta / 100) ^3.3 Ua = 117 1.5 × Sa × (Ta / 100) ^3.3 = 203 Measurement of the content of each monomer unit in the amorphous olefin copolymer is as follows. , Calculated using the ¹ H NMR method. The intrinsic viscosity [η] was measured in tetralin at 135 ° C. using an Ubbelohde viscometer. The sample is 300mg 100m
It was dissolved in 1-xylene to prepare a 3 mg / ml solution.
Further, the solution was diluted to １ ／, １ ／, and そ れ ぞ れ, and each was measured in a thermostatic oil bath at 135 ° C. (± 0.1 ° C.). The measurement was repeated three times at each concentration, and the obtained values were averaged and used. The molecular weight distribution was determined by gel permeation chromatography (GPC) (Waters, 15
(0C / GPC apparatus). Elution temperature is 140
° C, column used is Sodex Pack manufactured by Showa Denko KK
ed Column A-80M, molecular weight standard substance is polystyrene (manufactured by Tosoh Corporation, molecular weight 68-8,400,00
0) was used. The obtained polystyrene equivalent weight average molecular weight (Mw), number average molecular weight (Mn), and the ratio (Mw)
/ Mn) was taken as the molecular weight distribution. Measurement sample is about 5mg
Was dissolved in 5 ml of o-dichlorobenzene, about 1
The concentration was mg / ml. 40 of the obtained sample solution
0 μl was injected. Elution solvent flow rate is 1.0
ml / min and detected with a refractive index detector. Crystal Differential Scanning Calorimeter (DSC220C manufactured by Seiko Instruments Inc.)
The measurement was carried out at a rate of 10 ° C./min in both the temperature raising and the constant temperature processes. To determine the presence or absence of a peak of 1 J / g or more based on melting of the crystal and a peak of 1 J / g or more based on crystallization, use a differential scanning calorimeter (D made by Seiko Denshi Kogyo KK).
Using SC220C), measurement was performed at a rate of 10 ° C./min in both the temperature raising and constant temperature processes in accordance with JIS K 7122. Table 1 summarizes the results of each measurement.

Example 1 As a thermoplastic resin, a crystalline olefin resin, exelene EPX KS37G1, manufactured by Sumitomo Chemical Co., Ltd.
(MFR (230 ° C., 2.16 kg load) = 2.5 g /
10 minutes) 30% by weight of ethylene obtained in Reference Example 1
After mixing 100 parts by weight of the resin composition obtained by mixing the propylene-1-butene copolymer at a mixing ratio of 70% by weight and diatomaceous earth of 0.7% by weight, the position where the melting has advanced (L / D =
20) A single screw extruder (L / D = 42) with a diameter of 50 mm for injecting carbon dioxide gas at a high pressure.
A circular die having a diameter of 120 mm and a diameter of 120 mm was attached and extrusion foaming was performed to obtain a foamed molded product. The resulting foam is
It was a good foam having a thickness of 1.2 mm, a foaming ratio of 1.5 times and a soft feel.

Example 2 As a thermoplastic resin, a crystalline olefin resin, Sumitomo Noblen EL80F1 (M, manufactured by Sumitomo Chemical Co., Ltd.)
FR (230 ° C., 2.16 kg load) = 10 g / 10
Min) 30% by weight, 100 parts by weight of the resin composition obtained by mixing the ethylene-propylene-1-butene copolymer obtained in Reference Example 1 at a mixing ratio of 70% by weight, 8% by weight of azodicarbonamide and After mixing 1.4 parts by weight of a composite foaming agent having a composition of 92% by weight of sodium bicarbonate and 1.4 parts by weight of zinc oxide (foaming aid) with a tumbler, a width of 38 was obtained.
mm, diameter 4 with flat die of 8mm thickness
Extrusion foaming was performed with a 0 mm extruder to obtain a foamed sheet. The obtained foam was a good foam having a thickness of 25 mm, an expansion ratio of 2.4 times and a soft feel.

[0074]

[Table 1]

[0075]

As described above, according to the present invention,
A foaming thermoplastic resin composition containing a specific amorphous olefin (co) polymer and a thermoplastic resin, which is excellent in recyclability and disposability, and can simplify a production process, and A thermoplastic resin composition for foaming capable of obtaining a foamed molded article having a good balance of flexibility, heat resistance and impact resistance, a foamed molded article using the same, and a method for producing the same.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tadaaki Nishiyama 5-1, Anesaki Beach, Ichihara City, Chiba Prefecture Sumitomo Chemical Co., Ltd. F-term (reference) 4F074 AA17 AA18 AA19 AA20 AA24 AA25 BA01 BA03 BA04 BA13 BA14 BA16 BA17 BA31 BA32 BA33 CA22 CA23 DA24 DA35 4J002 AA01X BB03X BB05W BB12X BB14W BB15W BB17X GN00

Claims (3)

[Claims] 1. It contains the following components (A) and (B),
A thermoplastic resin composition for foaming, wherein the weight ratio of (A) / (B) is from 95/5 to 5/95. (A): Amorphousness in which the flexural modulus (Ua (MPa)) of the resin composition (b) obtained by blending with the homopolypropylene resin (a) measured according to JIS K7203 satisfies the following formula (1). Olefin (co) polymer Ua ≦ 1.5 × Sa × (Ta / 100) ^3.3 (1) (Sa represents the flexural modulus (MPa) measured according to JIS K7203 of (a), and Ta is (Indicates the content (% by weight) of (a) in (b).) (B): thermoplastic resin (however, excluding (A) above) 2. A foamed molded article comprising the thermoplastic resin composition for foaming according to claim 1. 3. A method for producing a foamed molded article, comprising extruding or injection molding the thermoplastic resin composition for foaming according to claim 1.