JP3377313B2 - Composite foam molded article, multilayer molded article using the same, and methods for producing them - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention has a non-foaming layer formed from a powder composition containing a specific thermoplastic elastomer and a foaming layer formed from a specific polyethylene-based expandable powder composition. The present invention relates to a characteristic composite foamed molded article, a multilayer molded article using the same, and a method for producing them.

[0002]

2. Description of the Related Art Conventionally, a composite foam molding having a non-foamed layer having a complicated pattern such as leather grain and stitches, and a foamed layer has been used as a skin material for automobile interior materials and the like. It is used as, by the powder molding method,
It is also known that a non-foamed layer obtained from a vinyl chloride resin powder composition is lined with a foamed layer obtained from a vinyl chloride resin foamable powder composition to produce the composition. However, the composite foamed molded product using vinyl chloride resin is not only inferior in lightness, but also generates acidic substances when incinerating used products, causing air pollution, acid rain, etc. However, there is a drawback that it is inferior, and it is not fully satisfactory.

The inventors of the present invention have proposed, as a composite foam molded article in which such drawbacks have been solved, a thermoplastic elastomer comprising a composition of an ethylene / α-olefin copolymer rubber and a polyolefin resin, or an ethylene / α-olefin. A non-foaming layer formed from a powder composition containing a thermoplastic elastomer consisting of a partially crosslinked composition of a system copolymer rubber and a polyolefin resin, and a foamable powder containing a pyrolyzable foaming agent and the elastomer or the like. A composite foam molded article having a foam layer molded from the composition has been proposed (JP-A-5-473, JP-A-5-228947, JP-A-5-208467). However, although such a composite foam molded article is excellent in that it is lightweight and clean and has a high expansion ratio of the foam layer, it does not have sufficient impact resilience, that is, cushioning properties, and is not always satisfactory. .

Under these circumstances, the inventors of the present invention have conducted extensive studies to produce a composite foam molded article having excellent cushioning properties, and as a result, as an expandable powder composition, an ethylene-based copolymer having a glycidyl group has been obtained. Polymer and 2 carboxyl groups
It was found that the use of a specific ethylene-based expandable powder composition consisting of at least one carboxylic acid and a thermal decomposition type foaming agent gives a composite foamed molded product having a foamed layer having excellent cushioning properties and a high expansion ratio. At the same time, various studies were further added to complete the present invention.

[0005]

[Means for Solving the Problems] That is, the present invention relates to a non-foamed layer formed from a powder composition containing a thermoplastic elastomer (A) below and a polyethylene-based expandable powder composition (B) below. The present invention provides a composite foamed molded article having excellent cushioning properties, a multilayer molded article using the same, and a method for producing the same. (A) From a thermoplastic elastomer composed of a composition of ethylene / α-olefin copolymer rubber and a polyolefin resin, or a partially cross-linked composition of ethylene / α-olefin copolymer rubber and a polyolefin resin It has a complex dynamic viscosity η ^* (1)
Is 1.5 × 10 ⁵ poise or less and Newtonian viscosity index n is 0.67 or less. (B) (a) The ethylene unit is 20 to 99.9 wt%, the unsaturated carboxylic acid glycidyl ester or unsaturated glycidyl ether unit is 0.1 to 30 wt%, and the ethylenically unsaturated ester unit other than the glycidyl ester is 0 to 50 wt%. A glycidyl group-containing ethylene copolymer, and (b) having 2 or more carboxyl groups and having a molecular weight of 100 wt parts of the copolymer.
A polyethylene-based expandable powder composition containing 0.1 to 30 parts by weight of carboxylic acids of 1500 or less and 0.1 to 20 parts by weight of (c) a thermal decomposition type foaming agent.

The present invention will be described in detail below. The present invention uses as a foaming layer raw material, (B) a polyethylene-based foamable powder composition, that is, (a) an ethylene unit of 20 to 99.9 wt%,
An unsaturated carboxylic acid glycidyl ester or unsaturated glycidyl ether unit is 0.1 to 30 wt%, an ethylenic unsaturated ester unit other than glycidyl ester is a glycidyl group-containing ethylene copolymer consisting of 0 to 50 wt%, and the copolymer 100 wt. (B) 0.1 to 30 wt% of carboxylic acids having 2 or more carboxyl groups and a molecular weight of 1500 or less per 1 part
Parts, and (c) a polyethylene-based expandable powder composition containing 0.1 to 20 parts by weight of a pyrolyzable foaming agent.

The unsaturated carboxylic acid glycidyl ester or unsaturated glycidyl ether used as a raw material of the glycidyl group-containing ethylene copolymer (a) which is one component of the foamable powder composition (B) is represented by the following general formula: The compound shown by is mentioned. (R represents an alkenyl group having 2 to 18 carbon atoms, and X represents a carbonyloxy group, a methyleneoxy group or a phenyleneoxy group.)

Representative examples of such compounds include glycidyl acrylate, glycidyl methacrylate, glycidyl itaconic acid ester, allyl glycidyl ether, methallyl glycidyl ether, and styrene-p-glycidyl ether. The unsaturated carboxylic acid glycidyl ester and unsaturated glycidyl ether units are usually contained in the ethylene copolymer in an amount of 0.1 to 30 wt%, preferably
0.5 to 20 wt% is contained.

Examples of the ethylenically unsaturated ester other than glycidyl ester include vinyl esters of carboxylic acids such as vinyl acetate and vinyl propionate, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, methacrylic acid. Examples thereof include esters of α, β-unsaturated carboxylic acids such as ethyl and butyl methacrylate. Vinyl acetate, methyl acrylate and ethyl acrylate are preferably used. The ethylenically unsaturated ester unit other than the glycidyl ester may not be contained in the ethylene copolymer, but may be contained as long as it is 50 wt% or less. If it exceeds 50 wt%, not only the heat resistance of the molded article is deteriorated but also when powder molding is carried out, powder flowability is significantly deteriorated when powdered, and powder molding becomes difficult,
When the one containing an ethylenically unsaturated ester unit is used, it is usually used in an amount of 50 wt% or less.

The ethylene copolymer (a), which is one of the components of the expandable powder composition (B) used in the present invention, is
The copolymer containing the monomer units as described above is, for example, 500 to 40 in the presence of a radical generator.
It can be produced by copolymerization at 00 atm and 100 to 300 ° C. in the presence or absence of a solvent or a chain transfer agent. It can also be produced by melt graft polymerization of a mixture of polyethylene, an unsaturated compound having a glycidyl group, a radical generator and the like by using an extruder or the like.

The ethylene-based copolymer (a) having a melt flow rate (MFR, according to JIS K6730) of less than 5 g / 10 min tends to have a low expansion ratio because it has a low foaming ratio.
The one of 5g / 10 minutes or more is usually used. MFR is 10g /
It is preferable to use the one for 10 minutes or more.

As the carboxylic acid (b) which is another component of the foamable powder composition (B) used in the present invention, a carboxylic acid having two or more carboxyl groups and a molecular weight of 1500 or less is used. To be done. Either solid or liquid may be used. Specific compounds include, for example, oxalic acid, maleic acid, malonic acid, phthalic acid, fumaric acid,
Succinic acid, 2,3-dimethylsuccinic acid, 2-ethyl-2-methylsuccinic acid, 2-phenylsuccinic acid, succinic acids such as 2-hydroxysuccinic acid, glutaric acid, 3-methylglutaric acid, 2,
4-Dimethylglutaric acid, glutaric acid such as 3,3-dimethylglutaric acid, adipic acid, adipic acid such as 3-methyladipic acid, sebacic acid, 1,4-cyclohexanecarboxylic acid, terephthalic acid, isophthalic acid, 5- Phthalic acids such as methylisophthalic acid, 5-methoxyisophthalic acid, and 5-hydroxyisophthalic acid,

Benzenetricarboxylic acids such as 1,3,5-benzenetricarboxylic acid and 1,2,4-benzenetricarboxylic acid,
1,2,3-propanetricarboxylic acid, 2-phenyl-1,2,3-propanetricarboxylic acid, 3-phenyl-1,2,3-propanetricarboxylic acid, 2-hydroxy-1,2,3-propanetricarboxylic acid Examples thereof include acids, propanetricarboxylic acids such as 3-hydroxy-1,2,3-propanetricarboxylic acid, and pyromellitic acid. Among them, the dissociation constant of primary acid in water is 50.
Those of × 10 ^-5 or less are preferably used.

The carboxylic acid (b) is used in an amount of 0.1 to 30 wt parts, preferably 1 to 20 wt parts, per 100 wt parts of the copolymer (a). If it is less than 0.1 wt parts, a foam with good impact resilience will not be obtained.If it is used in excess of 30 wt parts, the expansion ratio will decrease and the foam will become hard, resulting in foam with good impact resilience. I don't get a body.

The thermal decomposition type foaming agent (c) which is the other component of the foamable powder composition (B) used in the present invention.
As the foaming agent, a foaming agent having a decomposition temperature higher than the melting temperature of the copolymer (a) is used. For example, the decomposition temperature is about 120
Specific examples of compounds having a temperature of about 230 ° C to about 230 ° C, preferably about 150 ° C to 230 ° C include azo compounds such as azodicarbonamide, 2,2'-azobisisobutyronitrile and diazodiaminobenzene, benzene. Sulfonyl hydrazide, benzene-1,3-sulfonyl hydrazide,
Diphenyl sulfone-3,3'-disulfonyl hydrazide, diphenyl oxide-4,4'-disulfonyl hydrazide, 4,4 '
-Oxybis (benzenesulfonyl hydrazide), sulfonyl hydrazide compounds such as p-toluenesulfonyl hydrazide,

Nitroso compounds such as N, N'-dinitrosopentamethyleneteramine, N, N'-dinyloso-N, N'-dimethylterephthalamide, azide compounds such as terephthalazide and p-tertiarybutylbenzazide, Carbonates such as sodium bicarbonate, ammonium bicarbonate, ammonium carbonate and the like can be mentioned. Among them, azodicarbonamide is preferably used. The thermal decomposition type foaming agent (c) is 100 wt% of the copolymer (a).
The amount is usually 0.1 to 20 wt parts, preferably 5 to 10 wt parts.

The expandable powder composition (B) used in the present invention comprises the above-mentioned copolymer (a) and carboxylic acids.
(b) and a thermal decomposition type foaming agent (c) is contained, but in addition to such components, if necessary, for example, a phenol type,
Heat-resistant stabilizers such as sulfide-based, phosphite-based, amine-based, or amide-based stabilizers, antiaging agents, weathering stabilizers, antistatic agents, metal soaps, lubricants, pigments, foaming aids, foaming inhibitors Liquid coating agents, mold release agents and the like may also be added. The compounding is usually carried out at a temperature below the decomposition temperature of the foaming agent (c) and at a temperature at which the copolymer (a) and the carboxylic acid (b) do not undergo a crosslinking reaction.

In blending these components, for example, in the case of producing a powder composition for powder molding,
Normally, a blender with a jacket or a high speed rotating mixer is used. Above all, a compounding machine capable of preventing mutual adhesion of powders by applying shearing force, such as a super mixer, is preferably used. In this case, in order to prevent the heat fusion of the powder due to the heat generated by shearing, it is usually mixed while removing heat from the jacket. Further, in this case, as the copolymer (a), a powder crushed in advance is usually used. The average particle size of the Tyler standard sieve is usually 32 mesh or less, preferably 40 to 100 mesh. As the carboxylic acids (b),
When using a solid substance, a fine powder of 100 μm or less is usually used. When using a liquid one,
Usually, a method in which the thermal decomposition type foaming agent (c) is mixed after mixing with the copolymer (a) powder is adopted.

Further, the copolymer (a), the carboxylic acid (b), the thermal decomposition type foaming agent (c) and the like are kneaded using an extruder or the like, and then pulverized at a temperature below the glass transition point to obtain a powder. It is also possible to produce a powder composition for molding. Also in this case, the average particle size of the powder composition is usually 32 mesh or less on the Tyler standard sieve, and preferably 40 to 100 mesh.

The composite foamed molded product of the present invention comprises the non-foamed layer molded from the powder composition containing the thermoplastic elastomer (A) and the specific polyethylene foamable powder composition (B) as described above. As the ethylene / α-olefin copolymer rubber which is a component of the thermoplastic elastomer (A), it has, for example, an ethylene / propylene copolymer rubber, Examples of the rubber include olefin-based rubbers such as ethylene / propylene / non-conjugated diene copolymer rubber. Examples of the non-conjugated diene include dicyclopentadiene, ethylidene norbornene, 1,4-hexadiene, cyclooctadiene, methylene norbornene and the like. Among such ethylene / α-olefin-based copolymer rubbers, ethylene / propylene / ethylidene norbornene rubber (hereinafter referred to as EPDM) is more preferably used,
By using this, an elastomer having excellent heat resistance and tensile properties can be obtained.

The Mooney viscosity of the ethylene / α-olefin copolymer rubber (the Mooney viscosity measured at 100 ° C. according to ASTM D-927-57T (ML _{1 + 4} 100 ° C.)) is usually 130 or more and 350 or less, It is preferably 200 or more and 300 or less. Further, the ethylene / α-olefin copolymer rubber can be used in the form of an oil-extended olefin copolymer rubber by adding a mineral oil softener such as a paraffinic process oil to the ethylene / α-olefin copolymer rubber. In this case, not only the melt fluidity is improved but also the flexibility of the molded product is improved, which is preferable. The amount of the mineral oil-based softening agent added is usually 120 wt parts or less, preferably 100 wt parts or less per 100 parts by weight of the ethylene / α-olefin copolymer rubber.
30 to 120 wt parts.

Further, as the polyolefin resin which is another component constituting the thermoplastic elastomer (A), polypropylene, a copolymer of propylene and ethylene, and a copolymer of propylene and an α-olefin other than propylene are preferably used. . In particular, it is possible to reduce the hardness of the molded product by using a copolymer resin of propylene and butene.

If the melt flow rate of the polyolefin-based resin (MFR, measured according to JIS K-7210, 230 ° C., 2.16 kg load) is less than 20 g / 10 min, the powder particles melt and adhere to each other during powder molding. Since it becomes difficult and the strength of the molded product is reduced, 20 g / 10 min or more is usually used. It is preferably 50 g / 10 minutes or more.

The thermoplastic elastomer (A) used in the present invention is a composition of the above ethylene / α-olefin copolymer rubber and a polyolefin resin, or a portion obtained by dynamically crosslinking the composition. The cross-linking composition is included, but the weight ratio of the ethylene / α-olefin copolymer rubber to the olefin resin is usually 5:95 to 80:20.
Is preferred.

In producing the partially crosslinked composition, an organic peroxide is usually used as a crosslinking agent. Dialkyl peroxide is preferably used as the organic peroxide. Further, in the presence of a crosslinking aid such as a bismaleimide compound, it is preferable to dynamically crosslink using a very small amount of organic peroxide. In this case, ethylene / α-
Olefin-based copolymer rubber is appropriately crosslinked to improve heat resistance and, at the same time, high flow is obtained. The cross-linking agent is used in an amount of 1.5 wt parts or less, preferably 0.6 wt parts or less, per 100 wt parts of the total amount of the ethylene / α-olefin copolymer rubber and the polyolefin resin, and the organic peroxide is 0.2 wt parts or less.
Parts or less, preferably 0.1 WT parts or less, more preferably 0.07 parts or less.
Used below wt part. For dynamic crosslinking, a method of continuous kneading extrusion such as uniaxial kneading extrusion or biaxial kneading extrusion is suitable. In the case of twin-screw kneading and extrusion, when extrusion cross-linking is performed at a shear rate of <10 ³ sec ^-1 , the dispersed particle size of the ethylene / α-olefin copolymer rubber becomes large and it is difficult to realize the viscosity condition of the present invention. Therefore, it is preferable to carry out continuous extrusion crosslinking at a shear rate of ≧ 10 ³ sec ⁻¹ .

The thermoplastic elastomer (A) in the present invention has a complex dynamic viscosity η ^* (1) of 1.5 × 10 ⁵ poise or less, preferably 1.0 × 10 ⁵ poise or less, and a Newtonian viscosity index n of less than 0.6. , And preferably 0.59 or less. The complex dynamic viscosity η ^* (1) is a value measured at 250 ° C. and a frequency of 1 radian / second, and when it exceeds 1.5 × 10 ⁵ poise, the elastomer powder does not melt and flow on the mold surface. The powder cannot be molded by the powder molding method, which has a very low shear rate of 1 sec ^-1 or less during processing. Also, the Newtonian viscosity index n is the complex dynamic viscosity η ^* (1) and the frequency 10
It is a value calculated by the following formula using the complex dynamic viscosity η ^* (100) measured at 0 rad / sec. When ^{n = {logη * (1)} -logη * (100))} / 2 Newtonian viscosity index n exceeds 0.6, even if the complex dynamic viscosity eta ^* (1) is 1.5 × 10 ⁵ poise or less, The degree of frequency dependence of the complex dynamic viscosity becomes large, and the molding pressure such as powder molding, which is extremely small at 1 kg / cm ² or less, does not cause thermal fusion between the melted elastomer powder particles. It is not preferable because it tends to be completed and a molded product having low mechanical properties tends to be obtained.

In the present invention, when a partially crosslinked composition is used as the thermoplastic elastomer, an uncrosslinked ethylene-α-olefin copolymer rubber or ethylene-α-olefin copolymer resin is used as the elastomer 100 wt.
By blending 50 parts by weight or less with respect to 1 part, the flexibility of the molded product can be further improved. As the α-olefin in this case, propylene, butene and the like are used alone or in combination. Particularly preferred is an ethylene-propylene copolymer rubber having an ethylene content of 40 to 90% by weight, preferably 70 to 85% by weight, and having an ML _{1 + 4} 100 ° C. of 50 or less.

The powder composition containing the thermoplastic elastomer in the present invention is usually produced by pulverizing the composition containing the thermoplastic elastomer as described above at a temperature lower than the glass transition temperature. For example, a freeze pulverization method using liquid nitrogen is preferably used. The elastomer composition pellets cooled to −70 ° C. or lower, preferably −90 ° C. or lower can be obtained by a mechanical pulverization method using an impact pulverizer such as a ball mill. When crushed at a temperature higher than -70 ° C, the particle size of the crushed elastomer powder becomes coarse,
It is not preferable because the powder moldability is lowered. In order to prevent the polymer temperature from becoming higher than the glass transition temperature during the pulverization operation, a method that generates less heat and has high pulverization efficiency is preferable. Further, it is preferable that the crushing device itself is cooled by external cooling. The elastomer powder obtained is preferably pulverized to such an extent that 95% or more of the total weight of the elastomer powder passes through the Tyler standard sieve 32 mesh. 32
If the cumulative percentage on the sieve of the mesh exceeds 5%, it may be one of the causes of uneven thickness during pulverization and molding. This unevenness in thickness gives unevenness to the flexibility of the molded product and makes it easy to cause creases, which may be a factor that impairs the commercial value of the molded product.

The powder composition containing the thermoplastic elastomer of the present invention may contain an internally added release agent, and a methylpolysiloxane compound is preferably used as the internally added release agent. In this case, the methylpolysiloxane compound preferably has a viscosity at 25 ° C. of 20 centistokes or more, and more preferably 50 to 5000.
It is Centistokes. If the viscosity becomes too high,
The effectiveness as a release agent is reduced. The content of the internally added release agent is 2 wt parts or less per 100 wt parts of the powder composition, and when it is more than 2 parts by weight, the heat fusion between the elastomer powders is hindered and only a molded product having poor mechanical properties is obtained. The mold release agent may bleed on the surface of the mold, and the mold may be contaminated, which is not preferable.

Incorporation of the internally added release agent can be carried out at any time before and after pulverization. Further, the powder composition containing the thermoplastic elastomer in the present invention is a known heat-resistant stabilizer such as phenol-based, sulfite-based, phenylalkane-based, phosphite-based, amine-based or amide-based stabilizer, an antioxidant, It may contain a weather resistance stabilizer, an antistatic agent, a metallic soap, a lubricant such as wax, a coloring pigment and the like. When it is contained, it may be carried out at any time before and after pulverization.

The composite foamed molded article of the present invention is, for example, (A)
The non-foamed layer formed from the powder composition containing the thermoplastic elastomer of (1) is lined with the foamed layer formed from the polyethylene-based expandable powder composition (B). The powder molding method is usually adopted. Examples of the powder molding method include a fluidized-bed method, a powder sintering method, an electrostatic coating method, a powder spraying method, a powder rotational molding method, and a powder slush molding method (Japanese Patent Laid-Open No. 58-132507). Particularly, it is preferable to adopt the powder slush molding method.

When the powder slush molding method is adopted,
For example, (1) a container containing a thermoplastic elastomer powder composition and a mold having a complicated pattern inside, which is heated to a temperature sufficiently higher than the melting temperature of the powder, are integrated together and rotated and / or Alternatively, while shaking, the powder is attached to the cavity and melted, and the excess powder is discharged into the container. (2) Then, the container is removed, and the container containing the foamable composition is replaced with the foamable composition. A mold having the non-foaming layer obtained above, which was heated to a temperature sufficiently higher than the melting temperature, was integrated in the same manner as above, and the foamable composition was adhered from the container into the non-foaming layer in the same manner as above. It can be produced by melting, discharging the excess powder composition into a container, (3) after which the container is removed, and the resulting molded body is heat-foamed. Further, the composite foamed molded product of the present invention may have a composite layer composed of a non-foamed layer-foamed layer-non-foamed layer. In this case, it can be produced by carrying out (1) and (2) above, then carrying out (1) again, and then carrying out (3). Also, between the non-foamed layer and the foamed layer,
It is also possible to form an intermediate layer obtained from a non-foaming composition obtained by removing the thermal decomposition type foaming agent (c) from the polyethylene-based foaming powder composition (B). In this case, it is possible to obtain a composite foam molded article in which the adhesion between the non-foamed layer and the foamed layer is further improved.

The mold heating system used for powder molding is not particularly limited, and for example, a gas heating furnace system,
An electric heating furnace system, a heat medium oil circulation system, a dipping system in a heat medium oil or a heat fluidized sand, a high frequency induction heating system and the like can be mentioned. Even when foaming a molten powder composition, these heating sources are used. Can be used. The powder molding temperature is usually 160 to 300 ° C, preferably 18 to 300 ° C.
It is 0 to 280 ° C. The molding time is not particularly limited and is appropriately selected depending on the size of the molded body, the thickness of the molded body, and the like. The temperature for foaming the foam layer is usually 180-280.
℃, preferably 1800-260 ℃. The foaming time is not particularly limited and is appropriately selected depending on the thickness of the foam layer and the foaming ratio.

Thus, the composite foam molded article of the present invention can be obtained. The composite foam molded article of the present invention is not only excellent in impact resilience, that is, cushioning properties, but also has a high expansion ratio of the foam layer and is lightweight and clean. Since it is excellent, it can be used in various fields. Especially, it is preferably used as a skin layer of a multilayer molded article.

The multi-layer molded article having the composite foamed molded article of the present invention as a skin layer may be formed of, for example, polypropylene, propylene-α-olefin copolymer, propylene-
Examples thereof include multi-layer molded products using a thermoplastic resin such as an ethylene copolymer, a polystyrene resin, a polyethylene resin, and a methacrylic resin, and a thermosetting resin such as semi-hard urethane, hard urethane, and epoxy resin. Among them, polypropylene is preferably used as the thermoplastic resin and hard urethane is preferably used as the thermosetting resin. In addition, the thermoplastic resin used in the present invention may contain various fillers such as inorganic fillers, various fillers such as glass fibers, pigments, lubricants, antistatic agents, stabilizers and the like, if necessary.

As a method for laminating and integrating the skin layer and the thermoplastic resin layer, for example, compression molding is performed while the skin layer obtained by the powder molding method is held on the surface of the mold cavity for powder molding. Integrated with the mold base in the female or male mold for use, and supplying the thermoplastic resin melt between the inner surface of the skin layer (foaming layer side) and the female or male mold, and clamping the male and female molds to form the skin. A method of laminating and integrating a layer and a thermoplastic resin can be mentioned. According to this method, the skin layer on which the pattern of the mold is transferred is used for molding the thermoplastic resin while being held by the mold, so that a multilayer molded body in which the pattern does not collapse can be obtained. Further, the mold for molding the skin layer and the mold for molding the thermoplastic resin do not necessarily have to be the same, and for example, the skin layer is demolded from the mold and It is held in one of the other male and female molds, the thermoplastic resin melt is supplied between the skin layer and the other mold, the male and female molds are clamped, and the skin material and the thermoplastic resin are bonded and integrated. It can also be converted.

In supplying the melt of the thermoplastic resin, it is preferable to clamp the mold while supplying the mold while the male and female molds are not closed, or after supplying the mold. As compared with the method in which the above-mentioned method is used, the displacement of the skin layer is less likely to occur, and a multilayer molded article having an improved degree of pattern transfer can be obtained. The method of supplying the thermoplastic resin melt is not particularly limited, and for example, it can be supplied from a resin passage provided in the mold facing the back surface of the skin layer of the male and female molds. Alternatively, a molten resin supply nose may be inserted between the female and male molds to supply the molten resin, and after the molten resin is supplied, the supplied nose may be retracted outside the system to mold the male and female molds. Alternatively, a horizontal clamping device may be used.

As the male and female mold, a mold of a type in which the outer circumferences of the male and female molds are slidably closed can be used. By making the clearance of the sliding surface of such male and female dies almost equal to the thickness of the skin layer, the end of the molded product is used to mold the surplus skin material, and after molding, the surplus skin material is molded. It is also possible to fold it to the back surface of the above and completely cover the outer peripheral portion of the molded product with a skin material.

As a method of laminating and integrating the skin layer and the thermosetting resin layer, for example, when urethane is laminated, the skin layer obtained by the powder molding method is used as a mold for powder molding. A method of pouring and curing a mixed liquid of a curing catalyst such as a polyol and an amine and polyisocyanate while maintaining the cavity surface is used.

Thus, the multilayer molded article of the present invention can be obtained. The multilayer molded article of the present invention is excellent not only in cushioning properties and high-class feeling but also in light weight and cleanliness, and is used in various fields. . For example, in the automotive field, instrument panels, console boxes, armrests, headrests, door trims, rear panels, pillar trims, sun visors, luggage compartment trims, trunk lid trims, airbag storage boxes, seat buckles, headliners, glove boxes, steering wheel covers, Suitable for interior skin materials such as ceiling materials, kicking plates, change lever boots, interior moldings such as ceiling materials, spoilers, side moldings, license plate housings, mirror housings, air dam skirts, and mudguards.

In the field of home appliances / OA equipment, for example,
TV, video, washing machine, dryer, vacuum cleaner, cooler,
Suitable as an exterior member for air conditioners. In the field of sporting goods, for example, it is suitable for interior materials for boats, marine sports parts, etc., and in the field of construction and housing, for example, furniture, desks, chairs, gates, doors, fences, wall decoration materials, ceiling decoration materials, kitchens. Suitable for indoor floor materials such as washrooms and toilets, and can also be used for industrial products and miscellaneous goods.

[0042]

INDUSTRIAL APPLICABILITY The composite foam molded article of the present invention is not only excellent in cushioning properties, but also has a high expansion ratio of the foam layer and is also lightweight and clean, and therefore can be used in various fields. Among them, the foamed layer has excellent adhesion to the resin used as the core material, and is therefore preferably used as the skin layer of the multilayer molded body.

[0043]

EXAMPLES Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples. The appearances on the skin side and the foam side of the composite foam molded articles in Examples and Comparative Examples, the thickness of the composite foam molded article, the state of the foam layer cells, the foaming ratio of the foam layer, and the impact resilience were evaluated as follows.

Appearance of the composite foam molded article on the skin side The skin layer was visually observed and evaluated as follows. ◯: Meltability is good and no pinhole is observed. X: Poor meltability and pinholes are observed. Appearance of the foamed side of the composite foamed article The foamed layer was visually observed and evaluated as follows. ◯: There is no unevenness in thickness and foaming is uniform. Δ: There is unevenness in thickness, but foaming is almost uniform. X: The thickness is large and unevenly foamed. XX: Almost no foaming. Thickness of Composite Foamed Body The thicknesses of the non-foamed layer and the foamed layer were measured with a dial gauge manufactured by Toyo Seiki.

State of Cell of Foam Layer The cross section of the foam was visually observed and evaluated as follows. ◯: The cells are uniform. Δ: The cells are slightly non-uniform. X: The cells are non-uniform. Foaming Ratio of Foamed Layer The foamed layer was peeled off and calculated by the following formula. Foaming ratio = density of non-foamed layer / density of foamed layer The density of the foamed layer is the density meter (Dens manufactured by Toyo Seiki Seisakusho).
metric-H). Rebound resilience of foam layer In accordance with JIS K6301, let a specified iron bar fall freely at room temperature, collide it with the test surface, and measure the rebound resilience (%) from the height when the iron bar repels. Evaluated to. ⊚: Rebound resilience is 20% or more. ○: Rebound resilience is 10 to less than 20%. X: Repulsion elasticity is less than 10%. Dynamic viscoelasticity of thermoplastic elastomer composition Dynamic analyzer RD manufactured by Rheometrics
Using the S-7700 model, the dynamic viscoelasticity at a frequency of 1 radian / second and 100 radian / second at 250 ° C. was measured in a parallel plate mode with an applied strain of 5%, and a complex dynamic viscosity η ^* (1)
And η ^* (100) were calculated.

Reference Example 1 (Preparation of Thermoplastic Elastomer Powder Composition) EPD
M (ML _{1 + 4} 100 ° C = 242, propylene content = 28wt%, iodine value = 12) 100wt parts of mineral oil softener (Idemitsu Kosan, registered trademark Diana Process PW-380) 100wt parts of oil extension 50 wt parts of EPDM (ML _{1 + 4} 100 ° C = 53), 50 wt parts of propylene-ethylene random copolymer resin (ethylene content = 5 wt%, MFR = 90 g / 10 min) and a crosslinking aid (registered trademark of Sumitomo Chemical Co., Ltd. 0.4 wt parts of Sumifine BM-bismaleimide compound) was kneaded using a Banbury mixer for 10 minutes, and then pelletized in a master batch for crosslinking (hereinafter referred to as MB) using an extruder.

This M. B. Organic peroxide (Sanken Kako Co., Ltd., San Perox APO, 2,5-dimethyl-2,5-bis (t-butylperoxy) hexane) was added to 100 parts by weight.
04 wt parts was added, and dynamic crosslinking was performed at 220 ° C. using a twin-screw kneader (manufactured by Japan Steel Works, registered trademark TEX-44) to obtain elastomer composition pellets. This pellet was cooled to -100 ° C with liquid nitrogen and then freeze-ground to obtain a thermoplastic powder for molding with a complex dynamic viscosity η ^* (1) of 6.4 × 10 ³ poise and a Newtonian viscosity index n of 0.38. An elastomer powder was obtained. This powder is Tyler standard sieve 32
Passed 99 wt% through the mesh sieve.

Reference Example 2 (Preparation of Effervescent Powder Composition) Ethylene unit is 83%,
Ethylene copolymer powder with 12% glycidyl methacrylate units and 5% vinyl acetate units (Sumitomo Chemical Co., Ltd., registered trademark: Bondfast 70B-P, MFR90) 100wt
20 parts by weight of adipic acid (K ₁ = 3.7 × 10 ^-5 ), pyrolysis type foaming agent SELMIC C-191 (manufactured by Sankyo Kasei, azodicarboxylic acid amide, decomposition temperature 210 ° C) 5 parts by weight in a super mixer Then, the mixture was put in and mixed at 500 rpm for 3 minutes to obtain a polyethylene-based expandable powder composition. This powder passed 99% by weight through a 32 mesh Tyler standard sieve.

Example 1 In a gear oven at 300 ° C., a nickel flat plate wrinkled mold (15 cm × 15 cm) was heated. When the surface temperature of the mold reached 260 ° C., the thermoplastic elastomer powder composition obtained in Reference Example 1 was sprinkled for 7 seconds. Five seconds after discharging the excess powder, the foamable powder composition obtained in Reference Example 2 was sprinkled for 15 seconds, and the excess powder composition was discharged. Further, the mold was placed in a gear oven having an ambient temperature of 240 ° C. and heated for 120 seconds to foam the composition.
Next, the mold was taken out of the gear oven and cooled with water to release the composite foamed molded product from the mold. Table 1 shows the evaluation results of the composite foamed article.

Examples 2 to 6 In Example 1, instead of adipic acid, succinic acid (K ₁ =
6.4 × 10 ^-5 ) 10 wt parts, isophthalic acid (K ₁ = 24 × 10 ^-5 ) 5w
t part, terephthalic acid (K ₁ = 29 × 10 ^-5 ) 5wt part, dimer acid (made by Henkel Hakusui, liquid dicarboxylic acid Versadim 21)
6) The procedure of Example 1 was repeated except that an expandable powder composition containing 2 parts by weight and 5 parts by weight of 1,3,5-benzenetricarboxylic acid (manufactured by Nacalai Tesque) was used. The results are shown in Table 1.

Example 7 A nickel flat plate wrinkled mold (15 cm × 15 cm) was heated in a gear oven at 300 ° C. When the surface temperature of the mold reached 260 ° C., the thermoplastic elastomer powder composition obtained in Reference Example 1 was sprinkled for 5 seconds. 5 seconds after discharging the excess powder, the foamable powder composition (in Reference Example 2, ethylene-based copolymer powder bond first
Bondfast 20B (Sumitomo Chemical Co., Ltd., MFR20) 100 wt parts with 83% ethylene units, 12% glycidyl methacrylate units and 5 wt% ethylene units instead of 70B-P, 5 wt parts of terephthalic acid instead of adipic acid, foaming C-121 (manufactured by Sankyo Kasei, decomposition temperature 20
(6 ° C.) A composition prepared in the same manner as in Reference Example 2 except that 5 parts by weight was used) was sprinkled for 15 seconds, and the excess powder composition was discharged. Further, the mold was placed in a gear oven having an ambient temperature of 230 ° C. and heated for 150 seconds to foam the composition.
The results are shown in Table 1.

Example 8 In Example 7, instead of the foaming agent Celmic C-121,
C-1 (manufactured by Sankyo Kasei, decomposition temperature 205 ° C.) was carried out in accordance with Example 7 except that an expandable powder composition containing 5 parts by weight was used. The results are shown in Table 1.

Example 9 A nickel flat plate wrinkled mold (15 cm × 15 cm) was heated in a gear oven at 300 ° C. When the surface temperature of the mold reached 245 ° C., the thermoplastic elastomer powder composition obtained in Reference Example 1 was sprinkled for 7 seconds. Five seconds after discharging the excess powder, a foamable powder composition (in Reference Example 2, instead of adipic acid, phthalic acid (K ₁ = 110 × 10 5
^-5 ) 2wt part, CAP-50 instead of foaming agent celmic C-191
0 (manufactured by Sankyo Chemical Co., Ltd., aromatic vanamid, decomposition temperature 150 ℃) 5w
(composition prepared in the same manner as in Reference Example 2 except that t parts are used)
Sprinkle for 15 seconds and drain off excess powder composition.
Further, the mold was placed in a gear oven with an ambient temperature of 230 ° C. and heated for 120 seconds to foam the composition. The results are shown in Table 1.

Example 10 The procedure of Example 1 was repeated except that as the expandable powder composition, Bond Fast 20B was used instead of Ethylene Copolymer Powder Bond Fast 70B-P and 1 wt parts of terephthalic acid was used instead of adipic acid. The procedure of Example 1 was repeated except that the composition formulated in the same manner as in Reference Example 2 was used. The results are shown in Table 1.

Example 11 In Example 1, except that the ethylene copolymer powder Bondfast 20B was used instead of Bondfast 70B-P and 0.5 wt parts of terephthalic acid was used instead of adipic acid as the foamable powder composition. Was carried out in accordance with Example 1 except that the composition formulated in the same manner as in Reference Example 2 was used. The results are shown in Table 1.

Example 12 The procedure of Example 1 was repeated except that the foamable powder composition contained 83% ethylene units, 12% glycidyl methacrylate units and 5% vinyl acetate units instead of the ethylene copolymer powder Bondfast 70B-P. % Ethylene-based copolymer powder (registered trademark: Sumitomo Chemical Co., Ltd .: Bondfast 7B, MFR10), 2 wt parts of terephthalic acid instead of adipic acid, and C-121 instead of foaming agent Celmic C-191.
(Manufactured by Sankyo Kasei Co., Ltd., decomposition temperature 206 ° C.) In Example 1 except that 5 wt parts was used and the composition was the same as in Reference Example 2 except that a gear oven of 250 ° C. was used instead of the gear oven of 240 ° C. It carried out in conformity. The results are shown in Table 1.

Example 13 In Example 1, as an expandable powder composition, an ethylene copolymer having 85% ethylene units and 15% glycidyl methacrylate units instead of the ethylene copolymer powder Bondfast 70B-P was used. A coalescent powder (MFR280, manufactured by Sumitomo Chemical Co., Ltd.) was used according to Example 1 except that a composition compounded in the same manner as in Reference Example 2 was used except that 2 wt parts of terephthalic acid was used instead of adipic acid. The results are shown in Table 1.

Example 14 In Example 1, instead of the expandable powder composition obtained in Reference Example 2, 5 parts by weight of terephthalic acid and 5% by weight of Celmic C-191 were added to 100 parts by weight of Bondfast 70B-P.
The procedure was carried out in accordance with Example 1 except that the foamable powder composition obtained by kneading the parts with a Labo Plastomill at 120 ° C. and 50 rpm for 5 minutes and then freeze-grinding was used. The results are shown in Table 1.

Example 15 A nickel plate-shaped wrinkled mold (15 cm × 15 cm) was heated in a gear oven at 300 ° C. When the surface temperature of the mold reached 265 ° C., the thermoplastic elastomer powder composition obtained in Reference Example 1 was sprinkled for 5 seconds. 5 seconds after discharging the excess powder, the non-foaming powder composition (bond-fast 20B 100wt which is an ethylene-based copolymer powder)
The composition was prepared by blending 5 parts by weight of terephthalic acid in the same manner as in Reference Example 2) for 3 seconds. After discharging the excess powder, the mold was placed in a gear oven with an ambient temperature of 240 ° C. and heated for 30 seconds. Then, immediately the foamable powder composition (in Reference Example 2, Bondfast 70
A composition blended in the same manner as in Reference Example 2 except for using 20B instead of BP and 5 wt parts of terephthalic acid instead of adipic acid) was sprinkled for 15 seconds, and the excess powder composition was discharged. Further, after placing this mold in a gear oven with an ambient temperature of 240 ° C. and heating it for 180 seconds to foam the composition,
The composite foam molded article was released from the mold by cooling. The results are shown in Table 1.

Comparative Example 1 A composition prepared in the same manner as in Reference Example 2 except that adipic acid was not used was used as the foamable powder composition in Example 1, and the other operations were carried out in accordance with Example 1 did. The results are shown in Table 1.

Table 1 Skin side Skin layer Foaming side Foaming layer Foaming cell Foaming Foaming appearance thickness Appearance thickness state of magnification Elasticity Example 1 ○ 0.8 mm ○ 5.0 mm ○ 4.9 ◎ Example 2 ○ 0.8 ○ 4.8 ○ 4.8 ◎ Example 3 ○ 0.9 ○ 4.6 ○ 4.5 ◎ Example 4 ○ 0.8 ○ 5.1 ○ 5.2 ◎ Example 5 ○ 0.8 ○ 4.6 ○ 4.5 ◎ Example 6 ○ 0.8 ○ 4.4 ○ 4.7 ◎ Example 7 ○ 0.7 ○ 4.4 ○ 6.0 ◎ Example 8 ○ 0.8 ○ 4.8 ○ 6.0 ◎ Example 9 ○ 0.7 ○ 3.2 ○ 3.4 ◎ Example 10 ○ 0.8 ○ 3.8 ○ 4.0 ◎ Example 11 ○ 0.8 ○ 3.5 ○ 3.8 ○ Example 12 ○ 0.8 ○ 3.0 ○ 3.8 ◎ Example 13 ○ 0.8 ○ 4.0 ○ 3.5 ◎ Example 14 ○ 0.8 ○ 5.0 ○ 5.0 ◎ Example 15 ○ 0.7 + 0.3 ○ 4.0 ○ 5.0 ◎ Comparative Example 1 ○ 0.8 ○ 3.6 △ 3.5 × Comparative Example 2 ○ 0.8 ○ 3.5 ○ 3.5 × Comparative Example 3 ○ 0.8 ○ 3.6 △ 3.6 × Comparative Example 4 ○ 0.8 ○ 3.7 △ 3.7 ×

Comparative Example 2 In Example 1, as the expandable powder composition, EPDM and propylene were used instead of the ethylene copolymer powder.
Partially cross-linked thermoplastic elastomer powder made of butene random copolymer resin (complex dynamic viscosity η ^* (1) at frequency of 1 radian / second at 25 ° C is 1 × 10 ⁴ poise,
A composition prepared in the same manner as in Reference Example 2 was used, except that Newton's viscosity index n was 0.41).
It was carried out in accordance with. The results are shown in Table 1.

Comparative Example 3 A composition prepared in the same manner as in Reference Example 2 except that benzoic acid (K ₁ = 6.3 × 10 ⁻⁵ ) was used instead of adipic acid as the foaming powder composition in Example 1. The same procedure as in Example 1 was carried out. The results are shown in Table 1.

Comparative Example 4 A foaming powder composition was prepared in the same manner as in Reference Example 2 except that 5 parts by weight of polyacrylic acid (manufactured by Aldrich, average molecular weight 2000) was used instead of adipic acid. The composition was used, and otherwise the same as Example 1 was carried out. The results are shown in Table 1.

Example 16 In a gear oven at 300 ° C., a nickel flat plate wrinkled mold (30 cm × 30 cm) was heated. When the surface temperature of the mold reached 265 ° C., the thermoplastic elastomer powder composition obtained in Reference Example 1 was sprinkled for 5 seconds. Five seconds after discharging the excess powder, a foamable powder composition (in Reference Example 2, 20B instead of Bondfast 70B-P, 5 wt parts of terephthalic acid instead of adipic acid, and a foaming agent Celmic C-191) was used. Was sprayed for 15 seconds, and the excess powder composition was discharged. Further, the mold was placed in a gear oven having an ambient temperature of 240 ° C. and heated for 150 seconds to foam the composition. Next, the mold was taken out of the gear oven and cooled with water to release the composite foamed molded product from the mold.

Then, the obtained composite foamed molded article was set in a mold for polyurethane kept at 40 ° C. so that the foamed layer side faced upward, and a polyol (RI-29R, manufactured by Takeda Yakuhin) and an isocyanate ( IS-DIP, manufactured by Takeda Yakuhin) 100: 164
After pouring the mixture mixed in the ratio of 1 to laminate the hard urethane layer, the mixture was taken out from the mold. The obtained multilayer molded article had a non-foamed layer thickness of 0.8 mm and a foamed layer thickness of 4.8 mm.
The thickness of the hard urethane layer was 4.5 mm, and the adhesion between the foam layer and the hard urethane layer was very good, and the result of the 180 ° peel test (23 ° C, pulling speed 200 mm / min) was that the material peeled. was gotten.

Example 17 The thermoplastic elastomer powder 5000 obtained in Reference Example 1
g and 50 g of a black pigment (PV-801 manufactured by Sumika Color Co., Ltd.) were supplied to a 20 l supermixer and mixed at 500 rpm for 10 minutes to obtain an elastomer powder composition for powder molding (for non-foaming layer). As shown in FIG. 1, the thermoplastic elastomer powder composition 3 obtained above is put into a container 1, and a powder molding die 2 having a grain pattern and heated to 260 ° C. is opened at the opening of the container. The outer frames attached around both openings were closely attached and fixed together. Immediately after rotating the integrated container and mold by a uniaxial rotating device for 7 seconds, the powder 3 is supplied into the powder molding mold 2, and after the powder 3 is attached to the surface of the molding mold having a grain pattern and rotation is stopped. The excess powder was discharged into the container 1. Then, immediately, a container containing the foamable composition obtained in the same manner as in Reference Example 2 was attached, the container and the mold were integrated, and this was rotated for 15 seconds by a uniaxial rotating device to melt and adhere the foamable composition. Then, the excess foamable composition was discharged into a container.

Then, the mold was removed from the container, and the mold was heated at 230 ° C. for 2 minutes to form a foam layer. This was cooled and solidified to obtain a composite foam molded body 4 including a non-foamed layer 5 and a foamed layer 6. Next, as shown in FIG.
The powder molding die 2 while holding the composite foam molded body (skin material) 4 was transferred to the thermoplastic resin molding stage and integrated with the mold base 7 to form a thermoplastic resin molding female die 8. Subsequently, as shown in FIG. 3, while the female mold 8 for molding the thermoplastic resin and the male mold 9 for molding the thermoplastic resin are not closed, the composite foam molding 4 held in the female mold 8 is formed. Male mold 9
Polypropylene resin (Sumitomo Chemical Co., Ltd., Sumitomo Noblen AX 568, MFR 65g / 10 minutes) heated to 190 ° C is supplied as a thermoplastic resin melt 11 through the resin passage 10, and then the molding surface Molding of the thermoplastic resin 12 was completed by closing the mold with a pressing pressure of 50 kg / cm ² . Skin layer (composite foam molding) 4 and thermoplastic resin as shown in FIG.
A multilayer molded body 13 in which 12 and 12 were integrated was obtained. The cross section of the obtained multilayer molded body is shown in FIG. This product has a non-foam layer with a thickness of 0.7 mm, a foam layer with a thickness of 4 mm, and a thermoplastic resin of 2.3 m.
The thickness and the impact resilience were 20% or more, and the multi-layer molded article had a good appearance with the grain pattern transferred.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a container containing a resin composition for powder molding and a mold for powder molding.

FIG. 2 is a cross-sectional view of a powder molding die holding a composite foam molded article (skin material).

FIG. 3 is a cross-sectional view showing a state in which a powder molding die holding a composite foam molding (skin material) is integrated with a mold base and a thermoplastic resin is supplied from a male mold for thermoplastic resin molding. Is.

FIG. 4 is a cross-sectional view showing a state where a male mold for molding a thermoplastic resin and a female mold for molding a thermoplastic resin are closed.

FIG. 5 is a cross-sectional view of a multilayer molded body including a composite foam molded body (skin material) and a thermoplastic resin layer.

[Explanation of symbols]

1 ... Container 2 ... Mold for powder molding 3 ... Resin composition for powder molding 4 ... Composite foam molding (skin material) 5: Non-foaming layer 6 ... Foam layer 7: Mold base 8: Female mold for molding thermoplastic resin 9 ... Male mold for molding thermoplastic resin 10 ... Thermoplastic resin supply passage 11: Thermoplastic melt 12 ... Thermoplastic resin layer 13 ... Multilayer molded body

Continuation of front page (51) Int.Cl. ⁷ Identification code FI C08L 23/06 C08L 23/06 (72) Inventor Masayuki Tatsumi 2-10-1 Tsukahara, Takatsuki-shi, Osaka Sumitomo Chemical Co., Ltd. (72) Inventor Kenzo Konari 5-1, Anezaki Kaigan, Ichihara, Chiba Sumitomo Chemical Co., Ltd. (72) Inventor Satoshi Funakoshi 2-10-1, Tsukahara, Takatsuki, Osaka Sumitomo Chemical Co., Ltd. (56) References Special Kaihei 7-137189 (JP, A) JP 6-287323 (JP, A) JP 6-170871 (JP, A) JP 6-79815 (JP, A) JP 6-71799 ( JP, A) JP 6-286039 (JP, A) JP 4-73112 (JP, A) JP 1-195036 (JP, A) JP 57-20344 (JP, A) JP 49-75669 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B32B 1/00-35/00 B29C 41/00-41/52 C08J 9/06

Claims (6)

(57) [Claims] 1. A non-foamed layer formed from a powder composition containing a thermoplastic elastomer of the following (A), and the following (B):
And a foamed layer formed from the polyethylene-based expandable powder composition. (A) From a thermoplastic elastomer composed of a composition of ethylene / α-olefin copolymer rubber and a polyolefin resin, or a partially cross-linked composition of ethylene / α-olefin copolymer rubber and a polyolefin resin It has a complex dynamic viscosity η ^* (1)
Is 1.5 × 10 ⁵ poise or less and Newtonian viscosity index n is 0.67 or less. (B) (a) The ethylene unit is 20 to 99.9 wt%, the unsaturated carboxylic acid glycidyl ester or unsaturated glycidyl ether unit is 0.1 to 30 wt%, and the ethylenically unsaturated ester unit other than the glycidyl ester is 0 to 50 wt%. A glycidyl group-containing ethylene copolymer, and (b) having 2 or more carboxyl groups and having a molecular weight of 100 wt parts of the copolymer.
A polyethylene-based expandable powder composition containing 0.1 to 30 parts by weight of carboxylic acids of 1500 or less and 0.1 to 20 parts by weight of (c) a thermal decomposition type foaming agent. 2. A non-foaming layer obtained from a powder composition containing a thermoplastic elastomer of the following (A) is lined with a foaming layer obtained from a polyethylene-based expandable powder composition of the following (B) by a powder molding method. A method for producing a composite foam molded article, comprising: (A) From a thermoplastic elastomer composed of a composition of ethylene / α-olefin copolymer rubber and a polyolefin resin, or a partially cross-linked composition of ethylene / α-olefin copolymer rubber and a polyolefin resin It has a complex dynamic viscosity η ^* (1)
Is 1.5 × 10 ⁵ poise or less and Newtonian viscosity index n is 0.67 or less. (B) (a) The ethylene unit is 20 to 99.9 wt%, the unsaturated carboxylic acid glycidyl ester or unsaturated glycidyl ether unit is 0.1 to 30 wt%, and the ethylenically unsaturated ester unit other than the glycidyl ester is 0 to 50 wt%. A glycidyl group-containing ethylene copolymer, and (b) having 2 or more carboxyl groups and having a molecular weight of 100 wt parts of the copolymer.
A polyethylene-based expandable powder composition containing 0.1 to 30 parts by weight of carboxylic acids of 1500 or less and 0.1 to 20 parts by weight of (c) a thermal decomposition type foaming agent. 3. A multilayer molded article comprising a composite foam layer and a thermoplastic resin layer, wherein the composite foam layer is a non-foam layer formed from a powder composition containing a thermoplastic elastomer of the following (A); A multilayer molded article, which is a composite foamed layer having a foamed layer formed from the polyethylene-based expandable powder composition of (B). (A) From a thermoplastic elastomer composed of a composition of ethylene / α-olefin copolymer rubber and a polyolefin resin, or a partially cross-linked composition of ethylene / α-olefin copolymer rubber and a polyolefin resin It has a complex dynamic viscosity η ^* (1)
Is 1.5 × 10 ⁵ poise or less and Newtonian viscosity index n is 0.67 or less. (B) (a) The ethylene unit is 20 to 99.9 wt%, the unsaturated carboxylic acid glycidyl ester or unsaturated glycidyl ether unit is 0.1 to 30 wt%, and the ethylenically unsaturated ester unit other than the glycidyl ester is 0 to 50 wt%. A glycidyl group-containing ethylene copolymer, and (b) having 2 or more carboxyl groups and having a molecular weight of 100 wt parts of the copolymer.
A polyethylene-based expandable powder composition containing 0.1 to 30 parts by weight of carboxylic acids of 1500 or less and 0.1 to 20 parts by weight of (c) a thermal decomposition type foaming agent. 4. A method for producing a multilayer molded article comprising a composite foam layer and a thermoplastic resin layer, wherein the composite foam layer is formed into a powder composition containing a thermoplastic elastomer of the following (A) by a powder molding method. The non-foamed layer obtained by forming a polyethylene foamable powder composition (B) below is formed by backing the foamed layer, and then the composite layer is held in one of the male and female molds. A thermoplastic resin melt is supplied between the composite layer and the other die, and the male and female dies are clamped to bond and integrate the composite foam layer and the thermoplastic resin into a multilayer molded article. Manufacturing method. (A) From a thermoplastic elastomer composed of a composition of ethylene / α-olefin copolymer rubber and a polyolefin resin, or a partially cross-linked composition of ethylene / α-olefin copolymer rubber and a polyolefin resin It has a complex dynamic viscosity η ^* (1)
Is 1.5 × 10 ⁵ poise or less and Newtonian viscosity index n is 0.67 or less. (B) (a) The ethylene unit is 20 to 99.9 wt%, the unsaturated carboxylic acid glycidyl ester or unsaturated glycidyl ether unit is 0.1 to 30 wt%, and the ethylenically unsaturated ester unit other than the glycidyl ester is 0 to 50 wt%. A glycidyl group-containing ethylene copolymer, and (b) having 2 or more carboxyl groups and having a molecular weight of 100 wt parts of the copolymer.
A polyethylene-based expandable powder composition containing 0.1 to 30 parts by weight of carboxylic acids of 1500 or less and 0.1 to 20 parts by weight of (c) a thermal decomposition type foaming agent. 5. A multilayer molded article comprising a composite foam layer and a thermosetting resin layer, wherein the composite foam layer is a non-foam layer molded from a powder composition containing a thermoplastic elastomer of the following (A): A multi-layered molded article, which is a composite foamed layer having a foamed layer formed from the polyethylene-based expandable powder composition of the following (B). (A) From a thermoplastic elastomer composed of a composition of ethylene / α-olefin copolymer rubber and a polyolefin resin, or a partially cross-linked composition of ethylene / α-olefin copolymer rubber and a polyolefin resin It has a complex dynamic viscosity η ^* (1)
Is 1.5 × 10 ⁵ poise or less and Newtonian viscosity index n is 0.67 or less. (B) (a) The ethylene unit is 20 to 99.9 wt%, the unsaturated carboxylic acid glycidyl ester or unsaturated glycidyl ether unit is 0.1 to 30 wt%, and the ethylenically unsaturated ester unit other than the glycidyl ester is 0 to 50 wt%. A glycidyl group-containing ethylene copolymer, and (b) having 2 or more carboxyl groups and having a molecular weight of 100 wt parts of the copolymer.
A polyethylene-based expandable powder composition containing 0.1 to 30 parts by weight of carboxylic acids of 1500 or less and 0.1 to 20 parts by weight of (c) a thermal decomposition type foaming agent. 6. A method for producing a multilayer molded article comprising a composite foam layer and a thermosetting resin layer, wherein the composite foam layer is formed by a powder molding method to obtain a powder composition containing a thermoplastic elastomer of the following (A). The non-foamed layer formed is formed by backing the foamed layer formed by molding the polyethylene-based expandable powder composition (B) below, and then the composite layer and the thermosetting resin are bonded together. A method for producing a multilayer molded body, which is characterized by being integrated. (A) From a thermoplastic elastomer composed of a composition of ethylene / α-olefin copolymer rubber and a polyolefin resin, or a partially cross-linked composition of ethylene / α-olefin copolymer rubber and a polyolefin resin It has a complex dynamic viscosity η ^* (1)
Is 1.5 × 10 ⁵ poise or less and Newtonian viscosity index n is 0.67 or less. (B) (a) The ethylene unit is 20 to 99.9 wt%, the unsaturated carboxylic acid glycidyl ester or unsaturated glycidyl ether unit is 0.1 to 30 wt%, and the ethylenically unsaturated ester unit other than the glycidyl ester is 0 to 50 wt%. A glycidyl group-containing ethylene copolymer, and (b) having 2 or more carboxyl groups and having a molecular weight of 100 wt parts of the copolymer.
A polyethylene-based expandable powder composition containing 0.1 to 30 parts by weight of carboxylic acids of 1500 or less and 0.1 to 20 parts by weight of (c) a thermal decomposition type foaming agent.