JP2000281828A - Powdery polymer composition for blow holding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a powdery polymer composition for blow molding, comprising an epoxy-containing polymer as a component, excellent in storage stability of an un-crosslinked composition, capable of crosslinking and foaming in a short time, and capable of giving a foamed body which is little in compressed terminal strain, has excellent surface feeling and scarcely has surface transparency; powder and a foamed body made of the composition; method for producing a foamed body; and a molded article. SOLUTION: A powdery polymer composition for blow molding comprising (A) an epoxy-containing polymer, (B) a peroxide whose temperature for getting a half-life of 10 hr is 100 deg.C or more, (C) at least one kind out of quaternary ammonium salts and quaternary phosphonium salts and (D) a heat decomposition type foaming agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polymer composition for powder foam molding, a powder, a foam, a method for producing a foam, and a molded article. More specifically, the present invention contains a polymer containing an epoxy group as a polymer component, has excellent storage stability of an uncrosslinked product, is capable of crosslinking and foaming in a short time, has a small compression set, and has a low surface tension. Polymer composition capable of providing a foam which is excellent in skin and has almost no skin peel, powder of the composition, foam obtained from the composition, method for producing the foam, and molded article containing the foam It is about.

[0002]

2. Description of the Related Art Interior parts such as instrument panels, headrests, armrests and door trims of automobiles are becoming more and more soft than conventional hard types. These parts are composed of a textured skin layer and a foam layer which is a cushion layer. As the material of the foamed layer, a crosslinked foamable polymer composition is used, but the crosslinking progresses during storage to change the performance of the composition, and the problem that it is difficult to obtain a material having desired performance stably is obtained. is there. In addition, in the production of the interior parts of the automobile, a post-processing step in which an integrally molded product of a skin layer and a foam layer is produced by powder slush molding, and a resin serving as a reinforcing layer is attached to the surface side of the foam layer by injection molding. Needed. At this time, high temperature and high pressure (100
280 ° C. and a pressure of 15 to 600 kgf / cm ² ), which causes a problem that the foam layer is crushed and the function as a cushion material is remarkably reduced.

[0003] A method for stably obtaining a foam having a smooth and excellent surface skin and a small compression set which can withstand an atmosphere of high temperature and high pressure during injection molding has not been found.

[0004]

Under such circumstances, an object of the present invention is to contain a polymer containing an epoxy group as a polymer component, to provide excellent storage stability of an uncrosslinked product, and to achieve crosslinked foaming in a short time. A polymer composition capable of providing a foam having a small compression set, excellent surface skin, and little skin descaling, powder of the composition, a foam obtained from the composition, and the foam An object of the present invention is to provide a method for producing a body and a molded article containing the foam.

[0005]

That is, the present invention provides:
(A) a polymer containing an epoxy group, (B) a peroxide whose temperature for obtaining a half-life of 10 hours is 100 ° C. or higher, (C) at least one of a quaternary ammonium salt and a quaternary phosphonium salt And (D) a polymer composition for powder foam molding containing a pyrolytic foaming agent. The present invention also relates to a powder comprising the above polymer composition, a foam obtained by crosslinking and foaming the powder, and a method for producing the foam. Further, the present invention provides a two-layer molded article obtained by laminating a non-foamed layer of a thermoplastic elastomer composition or a vinyl chloride resin composition on a foamed layer of the foam, and a foamed layer side of the two-layer molded article. The present invention relates to a multilayer molded article obtained by laminating a protective layer of a thermoplastic resin composition or a thermoplastic elastomer composition.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the polymer (A) having an epoxy group is not particularly limited as long as it is a polymer having an epoxy group used as a crosslinking point. What is used can be used.

The polymer (A) having a preferred epoxy group is described below. A copolymer of an epoxy group-containing monomer used as a crosslinking point and a monomer copolymerizable therewith is preferred.

Examples of the epoxy group-containing monomer include unsaturated carboxylic acid glycidyl esters such as glycidyl acrylate, glycidyl methacrylate and itaconic acid glycidyl ester, and unsaturated glycidyl ethers such as vinyl glycidyl ether, allyl glycidyl ether and methacryl glycidyl ether. And glycidyl methacrylate and glycidyl acrylate are preferred.

The monomers copolymerizable with the epoxy group-containing monomer include carboxylic acid vinyl esters such as vinyl acetate and vinyl propionate; vinyl ketones such as methyl vinyl ketone and ethyl vinyl ketone; styrene; Methyl styrene, vinyl aromatic compounds such as vinyl toluene, methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, n-octyl acrylate, methoxymethyl acrylate, methoxyethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate and the like Vinyl monomers not having an epoxy group such as unsaturated carboxylic esters, ethylene, propylene, α-olefins such as 1-butene, and dienes such as butadiene can be given. One type or a combination of two or more types can be used for copolymerization with an epoxy group-containing monomer.

Examples of the copolymer (A) having an epoxy group include ethylene-vinyl acetate-epoxy group-containing monomer copolymers (eg, ethylene-vinyl acetate-glycidyl acrylate copolymer, ethylene-vinyl acetate -Glycidyl methacrylate copolymer), ethylene- (meth) acrylate-epoxy group-containing monomer copolymer (for example, ethylene-methyl acrylate-glycidyl acrylate copolymer, ethylene-methyl methacrylate-glycidyl acrylate copolymer, ethylene- Methyl acrylate-glycidyl methacrylate copolymer, ethylene-methyl methacrylate-glycidyl methacrylate copolymer), ethylene-vinyl acetate- (meth) acrylate-
Epoxy group-containing monomer copolymer (for example, ethylene-vinyl acetate-methyl acrylate-glycidyl acrylate copolymer, ethylene-vinyl acetate-methyl methacrylate-glycidyl acrylate copolymer), ethylene-
Propylene-epoxy group-containing monomer copolymer (eg, ethylene-propylene-glycidyl methacrylate copolymer, ethylene-propylene-glycidyl acrylate copolymer), (meth) acrylate-acrylonitrile-
Epoxy group-containing monomer copolymer (for example, acrylonitrile-methyl acrylate-glycidyl methacrylate copolymer, acrylonitrile-methyl methacrylate-
Glycidyl methacrylate copolymer), ethylene-butadiene-epoxy group-containing monomer copolymer (for example, ethylene-butadiene-glycidyl methacrylate copolymer,
Ethylene-butadiene-glycidyl acrylate copolymer), styrene-butadiene-epoxy group-containing monomer copolymer (for example, styrene-butadiene-glycidyl methacrylate copolymer, styrene-butadiene-glycidyl acrylate copolymer) and the like. .

The copolymer (A) having an epoxy group preferably contains 0.1 to 35% by weight, based on the total monomer units, of an epoxy group-containing monomer unit which is a crosslinking point, and more preferably contains an epoxy group. 0.1 to 35% by weight (more preferably 1 to 30% by weight) of a group-containing monomer, 30 to 99.8% by weight (more preferably 40 to 98% by weight) of ethylene, α-olefin or diene; 0.1 to 35% by weight of a vinyl monomer having no epoxy group (more preferably 1 to 35% by weight)
25% by weight) or 0.1% of an epoxy group-containing monomer.
-35% by weight (more preferably 1-30% by weight) and 65-99.9% by weight of a vinyl monomer having no epoxy group
(More preferably 70 to 99% by weight) with solution polymerization,
A polymer obtained by copolymerization by a known polymerization method such as emulsion polymerization, suspension polymerization, slurry polymerization, or gas phase polymerization is preferable.

The peroxide (B) used in the present invention
Is a peroxide whose temperature for obtaining a half-life of 10 hours is 100 ° C. or higher. If the temperature for obtaining a half-life of 10 hours is less than 100 ° C., there arises a problem that the storage stability of the uncrosslinked product and the resulting foam have skin pits and that the expansion ratio does not increase.

Specific examples of the peroxide (B) include 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, 2,5-bis (tert-butylperoxy) octane and tert-butyl. Peroxyacetate,
2,2-bis (tert-butylperoxy) butane, tert
-Butylperoxybenzoate, n-butyl-4,4
-Bis (tert-butylperoxy) valerate, di-te
rt-butyl diperoxyisophthalate, methyl ethyl ketone peroxide, dicumyl peroxide, 2,
5-dimethyl-2,5-di (tert-butylperoxy)
Hexane, αα'-bis (tert-butylperoxy-m
-Isopropyl) benzene, tert-butylcumyl peroxide, diisopropylbenzene hydroperoxide, di-tertbutyl peroxide, p-menthane hydroperoxide, 2,2-dimethyl-2,5-di (tert-butylperoxy) Hexin-3, 1,1,
3,3-tetramethylbutyl hydroperoxide,
2,5-dimethylhexane-2,5-dihydroperoxide, cumene hydroperoxide, tert-butyl hydroperoxide and the like. These may be used alone or in combination of two or more. Among them, αα′-bis (tert-butylperoxy-m-isopropyl) benzene, 2,5-dimethyl 2,5-di (te
(rt-butylperoxy) hexane is preferred.

The amount of the peroxide (B) is from 0.1 to 100 parts by weight per 100 parts by weight of the polymer (A) having an epoxy group.
It is preferably 10 parts by weight, more preferably 0.3 to 7 parts by weight. If the peroxide (B) is too small, the crosslinking density is too low, and the compression set of the foam increases,
On the other hand, if the peroxide (B) is excessive, the crosslinking density becomes too high, and the compression set becomes small, but the expansion ratio does not increase, and the storage stability of the uncrosslinked composition is poor.
Problems such as an increase in cost may occur.

The component (C) of the present invention is at least one of a quaternary ammonium salt and a quaternary phosphonium salt.

Examples of quaternary ammonium salts include octadecyltrimethylammonium bromide, hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, hexadecyldimethylbenzylammonium bromide, methylhexadecyldibenzylammonium bromide, hexadecylpyridium bromide, tetraethyl Ammonium bromide, tetrabutylammonium bromide, octadecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyldimethylbenzylammonium chloride, methylhexadecyldibenzylammonium chloride, hexadecylpyridium chloride, tetra Chill chloride, tetrabutylammonium chloride and the like.

Examples of quaternary phosphonium salts include triphenylbenzylphosphonium chloride, triphenylbenzylphosphonium bromide, triphenylbenzylphosphonium iodide, triphenyltrimethoxymethylphosphonium chloride, triethylbenzylphosphonium chloride, tricyclohexylbenzylphosphonium chloride, Trioctylmethylphosphonium dimethyl phosphate, tetrabutylphosphonium bromide, trioctylmethylphosphonium acetate and the like can be mentioned.

The amount of the component (C) is 10%.
It is preferably 0.1 to 10 parts by weight, more preferably 0.1 to 7 parts by weight, per 0 parts by weight. Component (C) may be used alone or in combination of two or more. When two or more types of the components (C) are used in combination, the total amount thereof is used. If the component (C) is too small, the storage stability of the uncrosslinked product is excellent, but the compression set of the foam may be inferior. On the other hand, if the component (C) is too large, the foam may crack. May occur, the storage stability of the uncrosslinked product may be poor, and the cost may be high.

The pyrolytic foaming agent (D) used in the present invention preferably has a decomposition temperature in the range of 120 to 230 ° C. Specific examples satisfying these conditions include azodicarbonamide, 2,2′-azobisisobutyronitrile, diazodiaminobenzene, benzenesulfonylhydrazide, benzene-1,3-sulfonylhydrazide, diphenylsulfone-3,3 -Disulfonylhydrazide, diphenyloxide-4,4'-disulfonylhydrazide, 4,4'-oxybis (benzenesulfonylhydrazide) p-toluenesulfonylhydrazide,
N, N'-nitrosopentamethylenetetramine, sodium bicarbonate and the like. Among them, azodicarbonamide is preferably used.

The amount of the thermal decomposition type foaming agent (D) is 0.1 to 100 parts by weight per 100 parts by weight of the polymer (A) having an epoxy group.
The amount is preferably 20 parts by weight, more preferably 0.3 to 13 parts by weight. The pyrolytic foaming agent (D) may be used alone or in combination of two or more. In addition, the thermal decomposition type foaming agent (D)
When two or more kinds are used in combination, the total amount is used. If the amount of the thermal decomposition type foaming agent (D) is too small, the foaming ratio is low, so that there is a problem in softness as a cushion material. On the other hand, if the amount of the thermal decomposition type foaming agent (D) is excessive, the surface of the foam is inferior. ,
There are cases where problems such as cracks entering the foam and breakage occur.

The above composition of the present invention is suitably used for powder foam molding.

The polymer composition for foam expansion molding of the present invention comprises:
In addition to the essential components (A) to (D), a crosslinking aid (E) and a foaming aid (F) can be added as needed. Specific examples of the crosslinking aid (E) include triallyl isocyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, N,
N'-m-phenylene bismaleimide, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, allyl methacrylate, nitrobenzene, p-quinone dioxime, p, p'-dibenzoylquinone dioxime, etc., which are used alone They may be used, or two or more kinds may be used in combination. Of these, triallyl isocyanurate and ethylene glycol dimethacrylate are preferred. The amount used is 0.1 to 100 parts by weight of the polymer (A) containing an epoxy group.
10 parts by weight are preferred. Specific examples of the foaming auxiliary include zinc stearate, calcium stearate, stearic acid, urea-based auxiliary, triethanolamine, zinc white, zinc carbonate, titanium white, carbon black and the like. Particularly preferred is zinc white. In the case of zinc white, the amount of addition is 0.1 to 100 parts by weight per 100 parts by weight of the polymer (A) containing an epoxy group.
The amount is 50 parts by weight, preferably 0.5 to 35 parts by weight, and the amount of other foaming aids is preferably about 0.1 to 10 parts by weight.
When zinc white is added, it is possible to obtain a foam having no surface roughness particularly at the time of high-temperature molding and having improved surface texture.

Further, an extruder is used to extrude reinforcing agents, fillers, plasticizers, anti-aging agents, stabilizers, ultraviolet absorbers, processing aids, mold release agents, etc., which are used in the ordinary resin and rubber industries. ,
After mixing using an ordinary kneader such as a Banbury mixer or a kneader, the mixture is granulated into pellets by an extruder.

The powder used for powder foam molding has an average sphere-equivalent particle diameter of preferably 50 to 1200 μm, more preferably 100 to 900 μm. If the particle diameter is too small, the powder cutting property is deteriorated, and the surface skin of the obtained foam may be inferior. On the other hand, if the particle diameter is too large, heat fusion between the pellets during powder slush molding is not performed. In some cases, the surface of the obtained foam is inferior. The sphere-converted average particle size is a particle size calculated as the diameter of a sphere having the same volume as the average volume of powder particles, and the average volume of the particles is used for cross-linking and foaming. It is a value calculated by dividing the total weight of 100 powder particles by the number of particles and dividing the average weight of the particles by the density of the crosslinked foaming powder composition.

The powder of the present invention can be crosslinked and foamed by heating at a temperature not lower than the melting temperature and not lower than the decomposition temperature of the decomposable foaming agent to form a foam. As a specific method, powder foam molding such as powder slush molding, rotational molding, spray molding, and electrodeposition molding can be employed, but it is particularly preferable to carry out cross-linking and foaming by powder slush foam molding from the viewpoint of cost and productivity.

The foam produced from the above powder has a small compression set, is excellent in surface skin, and has little skin ding. A two-layer molded article can be obtained by laminating a non-foamed layer of a thermoplastic elastomer composition or a vinyl chloride resin composition on the foamed layer of the foam.

Further, a multilayer molded article can be obtained by laminating a protective layer of a thermoplastic resin composition or a thermoplastic elastomer composition on the foam layer side of the two-layer molded article.

Further, by laminating a core material of a thermoplastic resin composition on the foam layer side of the two-layer molded body, a multilayer molded body different from the above can be obtained.

Furthermore, a multilayer molded article can be obtained by laminating a core layer of a thermoplastic resin composition on the protective layer side of the multilayer molded article.

Further, after forming a bead foam or a similar foam layer on the foam layer side of the two-layer molded article, the multilayer molded article can be obtained by bonding with a core material layer of a thermoplastic resin composition.

Further, a multilayer molded article can be obtained by combining the two-layer molded article and the core layer of the thermoplastic resin composition via a bead foam layer.

For the foam obtained by the powder slush molding method, for example, a mold which may have a pattern on its molding surface is preheated, and the cross-linking foaming powder of the present invention is supplied onto the mold to form a powder. After heat-sealing each other to obtain a sheet-like melt on the molding surface, excess powder not heat-sealed is removed, and then a heating furnace (temperature is usually 160 to 260 ° C., time is 15 seconds) After performing cross-linking and foaming for about 5 minutes, the mold is taken out of the heating furnace, the mold is cooled, and the cooled foam is removed from the mold.

A two-layer molded body composed of a non-foamed skin layer and a foamed layer formed by a powder slush molding method is preheated to a mold which may have a complicated pattern on its molding surface (the temperature is usually set to a predetermined value). The melting point of the skin resin powder at 170 to 320 ° C. or higher), supplying the above-mentioned skin layer resin powder onto the molding surface of the mold, and heat-fusing the powders together to form a sheet-like melt on the molding surface. After obtaining the product, excess powder not heat-sealed is removed, and then a powder for crosslinking and foaming is supplied on the sheet-like melt, and the powder is heat-sealed to each other to form a sheet on the molding surface. After obtaining a molten state, excess powder not heat-sealed is removed, and then a heating furnace (temperature is usually 1 to 1).
After cross-linking and foaming at 60 to 450 ° C. for 15 seconds to 5 minutes), the mixture is taken out of the heating furnace, the mold is cooled, and the cooled two-layer molded body is released from the mold.

The production of the multilayer molded body by the powder slush molding method is performed in accordance with the method for obtaining the two-layer molded body.
That is, for example, a multilayer molded body composed of a non-foamed skin layer, a foamed layer and a protective layer is obtained by forming a crosslinked foaming powder melting layer on the skin layer and then forming a thermoplastic resin or a thermoplastic resin composition on this surface. After the powders are supplied, the powders are heat-fused with each other to obtain a sheet-like melt on the molding surface, excess powder not heat-fused is removed, and then a heating furnace (at a temperature of usually 160 ~ 260 ° C, time is 15 seconds ~ 5 minutes)
After cross-linking and foaming, the mold is taken out of the heating furnace, the mold is cooled, and the mold is removed from the mold.

The crosslinked foaming powder composition of the present invention has excellent storage stability of an uncrosslinked product, so that crosslinking does not proceed during storage. In addition, the powdery slush molding method can be used to form a non-foamed skin layer and a foamed layer. When obtaining a two-layer molded body composed of, the compression set of the foam is small, the surface skin is excellent,
Since it has such features that there is almost no skin descaling, the appearance from the skin layer can be smooth and excellent and a good feel can be maintained even after the core material layer is attached. Furthermore, since a foam having sufficient performance can be obtained even under low-temperature, short-time crosslinking foaming conditions, cost can be reduced and productivity can be improved. Therefore, it can be widely used for various cushioning materials for automobiles, architecture, general industries, and the like, specifically, instrument panels, headrests, consoles, armrests, door trims and the like of automobiles.

[0036]

EXAMPLES Example 1 The present invention will be specifically described below using examples, but the present invention is not limited to these examples. Examples, Comparative Examples are the following polymers, peroxides, foaming agents,
The foaming aid and the additives described in the table were used. [Epoxy group-containing copolymer] (all ratios are by weight) Copolymer-1: ethylene / vinyl acetate / glycidyl methacrylate = 80/2/18 MFR = 340 g / 1
0 minutes Copolymer-2: Ethylene / vinyl acetate / glycidyl methacrylate = 88/5/7 MFR = 20 g / 10 minutes [Peroxide] • Perbutyl P40: αα′-bis (tert-butylperoxy-m-isopropyl) ) Benzene: temperature of 119 ° C for obtaining a 10-hour half-life ・ Perhexa 25B40: 2,5-dimethyl-2,5-
Di (tert-butylperoxy) hexane: temperature of 118 ° C. for obtaining a half-life of 10 hours. Perhexa 3M40: 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane: half-hour of 10 hours The temperature used for obtaining the period was 90 ° C. The peroxides used in Examples and Comparative Examples were all products diluted to 40% by weight. For example, in the case of adding 6 parts by weight in the table, when converted to a pure product, it is 2.4 parts by weight (6 parts by weight ×
0.4).

[Symbol of additive] ODTMA-Br: octadecyltrimethylammonium bromide ODTMA-Cl: octadecyltrimethylammonium chloride MTPP-Br: methyltriphenylphosphonium bromide TAIC-M60: Triallyl isocyanurate Nogard 445 manufactured by Nippon Kasei Co., Ltd. : Anti-aging agent Sumilizer TPS manufactured by Uniroyal Co., Ltd. Anti-aging agent manufactured by Sumitomo Chemical Co., Ltd. Cell Mike S: Foaming agent oxybenzenesulfonyl hydrazide manufactured by Sankyo Kasei Co., Ltd. Cell Mic C121: Foaming agent azo manufactured by Sankyo Chemical Co., Ltd. Dicarbonamide

Examples and comparative examples were performed as follows. [Kneading] The compositions shown in Tables 1 to 3 were charged into a Toyo Seiki Labo Plastomill (internal volume: 100 ml), and the temperature was adjusted to 105.
° C, rotation speed 50 rpm, kneading time 5 minutes, charge rate 8
Kneading was performed under the condition of 0%. [Freezing and pulverization] The kneading compound obtained above is pressed while hot to form a sheet, and then cut into approximately 5 mm squares with scissors. This cut sample is placed in liquid nitrogen for about 5
After immersion for minutes, the mixture was supplied to a laboratory freezing and crushing machine manufactured by Toyo Seiki to obtain a crosslinked foaming powder having an average sphere-equivalent particle diameter of 350 mμ. [Foaming method by powder slush molding] After a 150 mm square mold with a grain was preheated to 260 ° C., a resin powder for a skin layer was supplied on the mold in a heap, and was not heat-sealed after being left for 15 seconds. Was removed and kept for 30 seconds. Next, the crosslinked foaming powder obtained above was supplied onto the sheet-like molten material, and after being left for 20 seconds, excess crosslinked foaming powder that had not been heat-sealed was removed. Cross-linked foaming was performed for minutes. The mold taken out of the gear oven was cooled with water to obtain a two-layer molded body composed of a non-foamed skin layer and a foamed layer. Evaluation of the obtained foam molded article was performed as follows. [Measurement of Foaming Ratio] The skin layer of the above two-layer molded product was peeled off with a cutter knife, and only the foamed layer was used as a sample. Each honey degree was measured by an automatic density meter (Densimeter) manufactured by Toyo Seiki Seisaku-sho. Expansion ratio = density before foaming / density of foam [Evaluation of surface skin of foam] The state of the surface skin on the foam side of the two-layer molded body obtained by the powder slush molding was visually judged to be superior or inferior. When the unevenness of the surface skin was remarkable, when the reinforcing layer was pasted, the unevenness was transferred to the epidermis side, so it was judged that it could not be used. The following four grades evaluated. -Excellent surface skin and can be used practically ---------
−−− ○ ・ Some irregularities are seen on the surface, but practical use is possible.
−−− ○ △ ・ The surface has irregularities and cannot be used practically.
−−− △ ・ There are considerable irregularities on the surface and it cannot be used practically.
--- Evaluation of skin shade: Skin shade was determined as a measure of the degree of adhesion between the foamed layer of the two-layer molded article obtained by the powder slush molding and the black skin layer. When large bubbles are generated at the interface, the skin layer becomes extremely thin, and the adhesion at the interface becomes poor. In addition, if the skin layer is partially thinned, the design is poor and the skin is not practically used. Therefore, the interface is preferably a micro-foamed layer. The method is as follows, with the foam layer side facing the fluorescent lamp and viewed from the black skin side,
If there is an epidermis, the thin part of the epidermis looks bright,
The degree of interface adhesion can be determined. The following four grades evaluated.・ Can be used practically without skin erosion
○ ・ Slight skin shade is seen, but practical use is possible.
○ △ ・ There is a skin gap and it cannot be used practically −−−−−−−−
△ ・ The skin is so dark that it cannot be used practically.
× [Measurement of compression set] The foam was compressed using a hand press under the following conditions, and the permanent deformation was measured. Pressing temperature: 200 ° C. for the upper hot platen, 25 ° C. for the lower hot platen Compressive pressure: 50 Kfg / cm ² G Compressing time: 5 seconds Thickness of foam measured after standing at room temperature for 15 minutes after depressurization ··· L ₁ Thickness of foam before compression
... L ₀ (Calculation method) Compression set (%) = 100− (L ₁ / L ₀ ) 100 [Evaluation of storage stability]
The sample was placed in a thermostat at 55 ° C. or 55 ° C., and the change in formability with time was examined. The slash-molded powder was prepared the next day after the preparation of the crosslinked foaming powder, and the superiority of the surface skin of the foamed layer molded using the heat-treated crosslinked foaming powder was compared with the surface skin of the foamed layer. If the storage stability is inferior due to early crosslinking during storage, the fluidity deteriorates and the surface skin of the foamed layer becomes inferior. The following four levels were used for evaluation.・ Very good use possible −−−−−−−−−−−−−−−− Excellent and practical use possible −−−−−−−−−−−−−−
△ ・ Surface skin is inferior and cannot be used practically −−−−−−−− ・ Surface skin is remarkably inferior and cannot be practically used. Scale loupe (10
Times) and the cell size was measured.・ Less than 0.5mm ... micro ・ 0.5 to less than 1.5mm ... small ・ 1.5 to less than 2mm ... medium ・ 2.5mm or more ... large

[Consideration of Results] All the examples satisfying the conditions of the present invention show satisfactory results in all evaluation items. On the other hand, Comparative Example 1, which is out of the range of the present invention, uses a peroxide having a temperature of 100 ° C. or less for obtaining a half-life of 10 hours, so that the surface skin, skin darkness, and storage stability of the foam are inferior. . In Comparative Examples 2 to 6, since an ammonium compound other than the quaternary ammonium salt is used, the compression set of the foam is large, and the skin peeling appears.

[0040]

[Table 1]

[0041]

[Table 2]

[0042]

[Table 3]

[0043]

As described above, according to the present invention, a polymer containing an epoxy group is contained as one component, the storage stability of an uncrosslinked composition is excellent, and crosslinked foaming in a short time is possible. Further, a polymer composition for powder foam molding capable of providing a foam having a small compression set, an excellent surface skin, and almost no skin peeling, a method for producing a powder, a foam, and a foam using the composition, and molding. Body can be provided.

Claims (8)

[Claims] 1. A polymer (A) containing an epoxy group,
A peroxide (B) having a temperature of 100 ° C. or higher for obtaining a half-life of 0 hour, at least one of quaternary ammonium salts and quaternary phosphonium salts (C), and a pyrolytic foaming agent (D) A polymer composition for powder foam molding comprising: 2. (A) per 100 parts by weight of (B),
The polymer composition for powder foam molding according to claim 1, wherein the compounding amounts of (C) and (D) are 0.1 to 10 parts by weight, 0.1 to 10 parts by weight, and 0.1 to 20 parts by weight, respectively. . 3. (A) 0.1 to 50 parts by weight per 100 parts by weight
The polymer composition for powder foam molding according to claim 1, further comprising part by weight of zinc white. 4. The polymer composition for powder foam molding according to claim 1, which is used for powder slush foam molding. 5. A powder of the polymer composition for powder foam molding according to claim 1, 2 or 3. 6. A foam obtained by crosslinking and foaming the powder according to claim 5. 7. A method for producing a foam, wherein the powder according to claim 5 is crosslinked and foamed. 8. A two-layer molded article comprising a foamed layer of the foamed article according to claim 6 and a non-foamed layer made of a thermoplastic elastomer composition or a vinyl chloride resin composition laminated on the foamed layer.