JPH1024505A - Fuel container and fuel pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel container and a fuel transfer pipe of superior gasoline barrier properties, particularly of superior oxygen-containing gasoline barrier properties and also of superior resistance to impact. SOLUTION: A fuel container and a fuel transfer pipe are composed of multi- layer structural bodies with resin composition layers having an ethylene-vinyl alcohol copolymer saponified material (a) and resin fine particles (b) of core shell structure. Particularly, the resin composition is composed of the ethylene vinyl ester copolymer saponified material (a) of 60-99wt.% and resin fine particles (b) of core shell structure of 1-40wt.%, by which the glass transition temperature of resin of a core component of resin fine particles (b) of the core shell structure is set at -10 deg.C or under and the glass transition temperature of a shell component is set at 30 deg.C or above to provide effectively a fuel container and a fuel transfer pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel container and a fuel pipe which are excellent in permeation performance (gasoline barrier property) and impact resistance to automobile fuel.

[0002]

2. Description of the Related Art As a plastic fuel tank, a polyethylene single-layer type fuel tank is widely used, but has a drawback that it has a relatively high gasoline permeability. On the other hand, gasoline barrier properties have been improved by subjecting polyethylene tanks to sulfone treatment (JP-B-46-23914) or chlorofluorocarbon treatment (JP-B-47-21877, JP-B-53-15862). A method of improving the content, or a method of mixing a substance having a barrier property such as nylon into polyethylene (Japanese Patent Application Laid-Open No. 4-296331).
Has been taken. There has also been proposed a three-type five-layer structure in which a tank has a multilayer structure, a nylon is used for a barrier layer, and a high-density polyethylene layer is provided on both sides of the tank via an adhesive resin layer.

On the other hand, from the viewpoint of strengthening regulations on environmental pollution in recent years, and preventing air pollution and saving gasoline consumption, methanol, methanol and the like have been used to improve the octane number of gasoline and reduce the amount of unburned hydrocarbons in exhaust gas. ethanol,
Gasoline blended with an oxygen-containing compound such as MTBE (hereinafter abbreviated as oxygen-containing gasoline) is used mainly in the United States.

However, in the above-described method of forming a multilayer structure of polyethylene and nylon, and in the method of mixing and extruding nylon with polyethylene and simultaneously dispersing the nylon in a discontinuous thin layer in the polyethylene layer, etc. There is a problem with the barrier property against oxygenated gasoline.
In addition, the method of sulfone-treating or fluorine-treating a single polyethylene layer has a problem of insufficient barrier properties against oxygen-containing gasoline.

[0005] Under such circumstances, a multilayer tank of polyethylene and a saponified ethylene-vinyl ester copolymer (hereinafter abbreviated as EVOH) has been proposed as a container having excellent gasoline barrier properties, and is more favorable than the above-mentioned various fuel containers. It has become possible to obtain a good gasoline barrier property. However, the gasoline barrier property is not always sufficient for further strengthening of environmental regulations, and there is a problem in impact resistance.

In order to improve various problems of a fuel container having an EVOH resin as an intermediate layer, blending a polyolefin or a polyamide with the EVOH resin (Japanese Patent Laid-Open No. 6-2)
18891 and JP-A-7-52333) have also been proposed, but the gasoline barrier properties are greatly reduced and the melt stability is problematic. It is.

Further, a fuel pipe comprising a layer made of an EVOH resin or a composition mainly composed of an EVOH resin and a polyamide layer (Japanese Patent Publication No. 4-55392, Japanese Patent Application Laid-Open No. 7-52333) has been proposed. At present, there is no one that sufficiently satisfies both gasoline barrier properties and impact resistance.

[0008]

[Problems to be solved by the present invention] In view of this situation,
It is of great significance to provide a fuel container and a fuel pipe having good gasoline barrier properties and excellent impact resistance. Thus, the present invention provides a gasoline barrier property, particularly an oxygen-containing gasoline barrier property, by studying the composition of a resin composition containing EVOH as a main component.
Moreover, an object of the present invention is to provide a fuel container and a fuel tank which are excellent in impact resistance. As a result, not only is it adapted to environmental issues, but also the safety in actual use is greatly enhanced.

[0009]

SUMMARY OF THE INVENTION The object of the present invention is to provide ethylene-
This is achieved by providing a fuel container or a fuel pipe having a multilayer structure having a resin composition layer comprising a saponified vinyl alcohol copolymer (a) and fine resin particles (b) having a core-shell structure. Here, when the resin composition comprises 60 to 99% by weight of a saponified ethylene-vinyl ester copolymer (a) and 1 to 40% by weight of fine resin particles (b) having a core-shell structure, or a resin having a core-shell structure The above object is effectively achieved when the resin of the core component of the fine particles (b) has a glass transition temperature of −10 ° C. or lower and the shell component has a glass transition temperature of 30 ° C. or higher.

The above object is also effective when the resin composition layer and the high-density polyethylene layer are laminated via an adhesive resin layer, or when the resin composition layer and the polyamide resin layer are laminated. Is achieved. In addition, it is more effectively achieved when the fuel container or the fuel pipe is used for oxygenated gasoline.

BEST MODE FOR CARRYING OUT THE INVENTION

In the present invention, EVOH is obtained by saponifying an ethylene-vinyl ester copolymer, and preferably has an ethylene content of 20 to 60 mol%. If the ethylene content is less than 20 mol%, melt moldability is poor, and gasoline barrier properties under high humidity may be deteriorated. It is more preferably at least 25 mol%, and most preferably at least 30 mol%. On the other hand, if the ethylene content exceeds 60 mol%, the gasoline barrier properties deteriorate. It is more preferably at most 50 mol%, further preferably at most 40 mol%.

As the vinyl ester, a typical example is vinyl acetate. Other fatty acid vinyl esters (vinyl propionate, vinyl pivalate, etc.)
Can also be used.

[0013] Further, within the range not to impair the gist of the present invention, E
VOH may contain a copolymer component. Although the copolymerization component is not particularly limited, the vinyl silane compound 0.0
When 002-0.2 mol% is contained, the consistency of the melt viscosity with the base resin at the time of co-extrusion is improved, and not only a uniform co-extruded multilayer film can be produced, but also E
The dispersibility when VOHs are used in a blend is improved, which is effective in improving moldability and the like. Here, as the vinylsilane-based compound, for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (β-methoxyethoxy) silane, 3- (trimethoxysilyl)
Propyl methacrylate. Among them, vinyltrimethoxysilane and vinyltriethoxysilane are preferably used. Also, other comonomers [for example, propylene, butylene, unsaturated carboxylic acid or its ester (meth) acrylic acid, (meth) acrylate)
And vinylpyrrolidone (eg, N-vinylpyrrolidone)].

The preferred melt index (MI) (210 ° C., 2160 g load) of the EVOH used in the present invention is as follows:
0.1-50g / 10min, optimally 0.5-20g / 1
0 minutes.

In the present invention, it may be more preferable to use one or more EVOHs having different ethylene contents and / or saponification degrees in a blend.

The resin forming the core component in the resin fine particles having a core-shell structure of the present invention is not particularly limited, but its glass transition temperature is preferably -10 ° C or lower, and more preferably -30 ° C or lower. Is more preferable. When the glass transition temperature is higher than −10 ° C., sufficient thermoformability may not be obtained, for example, the corners of the molded product become thinner during thermoforming. Examples of the resin forming the core component include a resin obtained by polymerizing a conjugated diene monomer or an alkyl acrylate monomer or a mixed monomer thereof.

Examples of the conjugated diene used as a raw material monomer include butadiene, isoprene, chloroprene and the like, butadiene is particularly preferably used. Similarly, examples of the alkyl acrylate used as a raw material monomer include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate, with butyl acrylate being particularly preferred.

Here, as the resin forming the core component, a copolymer resin using a comonomer may be used in addition to the above raw material monomers. The comonomer is not particularly limited as long as it is a monomer copolymerizable with a conjugated diene or an alkyl acrylate, and may be aromatic vinyl such as styrene, vinyltoluene and α-methylstyrene; Various monomers such as vinyl cyanide such as acrylonitrile and methacrylonitrile; vinylidene cyanide; and alkyl methacrylate such as methyl methacrylate and butyl methacrylate.

When a copolymer resin is used as the resin forming the core component, when the conjugated diene is not contained as a raw material monomer, or when the conjugated diene is contained, the amount of the total When the content is 20% or less, excellent thermoformability may be achieved by using a small amount of a crosslinking monomer and a grafting monomer.

Examples of the crosslinking monomer include aromatic divinyl monomers such as divinylbenzene; ethylene glycol diacrylate, ethylene glycol dimethacrylate, butylene glycol diacrylate, hexanediol diacrylate, hexanediol dimethacrylate, and oligoethylene glycol diacrylate. Oligoethylene glycol dimethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, trimethylolpropane trimethacrylate and the like polyol polyacrylate or polyol polymethacrylate can be used, butylene butylene glycol diacrylate, especially hexane Diol diacrylate is preferred. Further, as the grafted monomer, allyl acrylate, allyl methacrylate, diallyl maleate, diallyl fumarate, unsaturated allyl carboxylate such as diallyl itaconate, etc. can be used, and especially allyl methacrylate is preferably used. .

Each of such a crosslinking monomer and a grafting monomer is used in an amount of 0.01 to 5% by weight, preferably 0.1 to 5% by weight, based on the total amount of the monomers used for polymerization of the resin forming the core component. ~
It is preferably used in the range of 2% by weight. The ratio of the resin forming the core component to the entire resin fine particles is 50 to
A range of 90% by weight is preferred. When the amount of the core component is less than or more than this range, the effect of improving the thermoformability of the resin composition obtained by melting and mixing the resulting resin fine particles may not be sufficient.

On the other hand, the resin forming the shell component preferably has a glass transition temperature of 30 ° C. or more,
More preferably, it is the above. If the glass transition temperature of the shell portion is lower than 30 ° C., handling of the produced core-shell polymer in each step from dehydration drying to melting and mixing into a resin is difficult due to its tackiness, and lacks practicality. is there.

Examples of monomers used for polymerization of the resin forming the shell component include alkyl methacrylates such as methyl methacrylate and ethyl methacrylate; aromatic vinyls such as styrene, vinyl toluene and α-methyl styrene; aromatic vinylidene; Examples thereof include vinyl cyanide such as acrylonitrile and methacrylonitrile; and vinyl polymerizable monomers such as vinylidene cyanide. Methyl methacrylate, styrene, and acrylonitrile are particularly preferably used.

Here, as the resin forming the shell component, a copolymer resin using a comonomer may be used in addition to the above-mentioned raw material monomers. Examples of the copolymerizable monomer include alkyl acrylates such as ethyl acrylate and butyl acrylate; alkyl methacrylates such as methyl methacrylate and butyl methacrylate; aromatic vinyls such as styrene, vinyl toluene and α-methyl styrene; aromatic vinylidene; acrylonitrile And vinyl cyanide such as methacrylonitrile; and vinylidene cyanide.

Further, when the resin forming the shell component has a polar functional group, it is preferable from the viewpoint of improving the miscibility with EVOH. Among them, when an unsaturated carboxylic acid or its monoalkyl ester is used as a comonomer used for the resin forming the shell component, the miscibility with EVOH is improved due to the presence of the polar functional group. preferable. Examples of unsaturated carboxylic acids include maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, aconitic acid, methylene romanic acid, α-methylene glutaric acid, etc., with itaconic acid being particularly preferred. Also, as the monoalkyl ester,
Those containing an alcohol residue having 1 to 6 carbon atoms are exemplified.
An example is maleic acid monoethyl ester. The unsaturated dicarboxylic acid or its monoalkyl ester is used in an amount of 1 to 40% by weight, preferably 1 to 20% by weight, based on the total amount of monomers forming the shell component.

Further, similarly to the resin forming the core component,
When a crosslinkable monomer or a grafted monomer is used as a copolymer component, excellent thermoformability may be achieved in some cases. The crosslinkable monomer or grafting monomer used is the same as in the case of the core component, and is used in the range of 0.01 to 5% by weight, particularly 0.1 to 2% by weight of the total amount of the monomers. Is preferred.

The ratio of the resin forming the shell component to the entire resin fine particles is preferably in the range of 10 to 50% by weight.
When the shell component is less than or more than this weight range, the effect of improving the thermoformability of the resin composition obtained by melting and mixing the resulting resin fine particles may not be sufficient.

The method for producing fine resin particles having a core-shell structure in the present invention is not particularly limited.
In general, it can be obtained by a continuous multi-stage seed emulsion polymerization method or the like in which the polymer of the previous stage is sequentially coated with the polymer of the subsequent stage. That is, a method in which a core component is formed in the first-stage polymerization and a shell portion is formed in the second-stage polymerization is preferably employed. After separating the polymer by freeze-thawing or salting-out the latex produced by such a polymerization method, the latex can be taken out as particles, flakes, or powder by centrifugal dehydration, drying, or the like. Also,
Fine resin particles having a core-shell structure can also be extracted from latex by spray drying using a spray dryer.

Further, the resin fine particles having a core-shell structure thus taken out are subjected to various methods such as a heat treatment in a dryer or a heat treatment by passing through an extruder, and a dehydrating agent under an inert gas atmosphere. When the shell has a carboxyl group by performing the dehydration treatment, resin fine particles having a core-shell structure in which at least a part of the carboxyl group is an acid anhydride type can be obtained.

The average particle diameter of the fine resin particles having a core-shell structure produced as described above is 100 to 1000.
nm, preferably in the range of 120 to 750 nm. Further, the core or shell of the resin fine particles having a core-shell structure of the present invention may be of a multilayer type. However, when the shell has a functional group, it is preferable that a resin layer having a functional group be present in the outermost layer of the shell in order to improve compatibility with EVOH.

The resin composition of the present invention contains a hydrotalcite-based compound, a hindered phenol-based, a hindered amine-based heat stabilizer, a higher aliphatic acid, in order to enhance the effects of the present invention and to improve the melt stability and the like. It is preferable to add one or more metal salts of carboxylic acids (for example, calcium stearate, magnesium stearate, etc.) to the resin composition in an amount of 0.01 to 1% by weight.

Further, an alkali metal ion such as lithium ion, sodium ion and potassium ion is added to EVO.
The addition of 10 to 500 ppm with respect to H (a) also enhances the effect of the present invention, and is effective for improving interlayer adhesion and compatibility of the resin composition. Examples of the alkali metal compound include an aliphatic carboxylate of a monovalent metal, an aromatic carboxylate, a phosphate, and a metal complex.
Sodium acetate, potassium acetate, sodium phosphate, lithium phosphate, sodium stearate, potassium stearate, sodium ethylenediaminetetraacetate and the like, preferably, sodium acetate, potassium acetate, sodium phosphate, lithium phosphate, sodium stearate, And potassium stearate.

Various additives may be added to the resin composition of the present invention, if necessary. Examples of such additives include antioxidants, plasticizers, heat stabilizers, ultraviolet absorbers, antistatic agents, lubricants, colorants, fillers, or other high molecular compounds, and Blends can be blended as long as the effects of the present invention are not impaired. Many other high molecular compounds can also be blended to such an extent that the effects of the present invention are not impaired.

The mixing ratio of each component (a) and (b) in the present invention is not particularly limited, but the content of the resin fine particles (b) is 1 to 40% by weight, preferably 5 to 3%.
0% by weight, more preferably 10 to 20% by weight.
When the content of (b) is 1% by weight or less, the resulting containers and pipes have insufficient impact resistance, and when the content of (b) is 40% by weight or more, the gas barrier properties are significantly reduced. There is a problem to do.

The laminated structure of the laminated structure including the resin composition layer is not particularly limited, but it is possible to laminate the resin composition layer and the high-density polyethylene layer via an adhesive resin layer. preferable. This is because the gas barrier property under high humidity, the strength, and the like are improved as compared with the case where the resin composition is used in a single layer. This configuration is particularly suitable for use as a fuel container.

In the present invention, high-density polyethylene is
For example, it is obtained by using a Ziegler catalyst under high or medium pressure and has a density of 0.941 to 0.965 g / c.
m ³ , preferably 0.945 to 0.96 g / cm ³ . In the present invention, a preferable melt index (MI) of the high-density polyethylene is (210 ° C., 2160
g measured under a load) is 0.009 to 0.1 g / 1.
0 minutes, preferably 0.01 to 0.6 g / 10 minutes.

By laminating such a high-density polyethylene layer on the inner layer or the inner and outer layers of the resin composition layer, as shown in Examples described later, a fuel container having excellent barrier properties and excellent impact resistance can be obtained. Fuel pipe can be obtained. The high-density polyethylene layer is preferably in the innermost layer, or the innermost layer-outermost layer, but the other resin layer is laminated on the innermost layer, or the innermost layer-outermost layer, according to the present invention. Free as long as the purpose is not hindered. Further, it is free to mix another resin or the like in the high-density polyethylene layer as long as the object of the present invention is not hindered.

The resin used for the adhesive resin layer is not particularly limited, but may be a polyurethane-based or polyester-based one-pack or two-pack curable adhesive, an unsaturated carboxylic acid or an anhydride thereof (anhydrous anhydride). Maleic acid, etc.) to an olefin polymer or copolymer [polyethylene @ low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ultra low density polyethylene (SLDP)
E)｝, ethylene-vinyl acetate copolymer, ethylene-
(Meth) acrylic acid ester (methyl ester or ethyl ester) copolymer] is preferably used. By providing such an adhesive resin layer, it is possible to obtain a fuel tank and a fuel pipe which are excellent in interlayer adhesiveness and which are excellent in barrier properties and impact resistance which are the objects of the present invention.

Further, it is more preferable that the adhesive resin is a carboxylic acid-modified polyethylene resin from the viewpoint of adhesiveness with a high-density polyethylene resin or a polyamide resin or compatibility at the time of scrap recovery. Examples of such a carboxylic acid-modified polyethylene resin include polyethylene {low density polyethylene (LDPE), linear low density polyethylene (LLDPE), very low density polyethylene (SLDPE)}, ethylene-vinyl acetate copolymer, ethylene- Carboxylic acid-modified (meth) acrylic ester (methyl ester or ethyl ester) copolymers and the like can be mentioned.

As another preferred structure of the laminated structure including the resin composition layer, it is preferable that the resin composition layer is laminated with a polyamide resin layer. Compared to the case where the resin composition is used in a single layer, strength,
This is because the rigidity and the like can be improved, and this is particularly effective when used as a fuel pipe.

The polyamide resin used for the polyamide resin layer is not particularly limited. Examples thereof include polycaproamide (nylon-6), polyundecaneamide (nylon-11), polylauryl lactam (nylon-12), and polylauryl lactam (nylon-12). Hexamethylene adipamide (nylon-
6,6), polyhexamethylene sebacamide (nylon-
6,12), caprolactam / lauryl lactam copolymer (nylon-6 / 12), caprolactam / aminoundecanoic acid copolymer (nylon-6 /
11), caprolactam / ω-aminononanoic acid copolymer (nylon-6 / 9), caprolactam / hexamethylenediammonium adipate copolymer (nylon-6 /
6,6) and copolymers such as caprolactam / hexamethylenediammonium adipate / hexamethylenediammonium sebacate copolymer (nylon-6 / 6,6 / 6,12). These polyamide resins can be used alone or in combination of two or more.

In the present invention, a scrap collected layer can be provided as needed. Here, as the scrap collected product, a molding loss portion generated when manufacturing a molded product such as a hollow container, a tubular container, and a tubular body, and a crushed product of the scrap collected product after being used by general consumers, and the like. is there. Also, scrap can be mixed with a high-density polyethylene layer or a polyamide layer. The high-density polyethylene layer of the present invention is the (c) layer, the adhesive resin layer is the (d) layer, the resin composition layer comprising EVOH and fine particles having a core-shell structure is (e), and the scrap recovered material layer is the (r) layer. In this case, a multi-layer structure having the following layer configuration is given as a typical example.

3 layers e / d / c 4 layers e / d / r / c, e / d / c / r 5 layers c / d / e / d / c, r / d / e / d / c,
c / d / e / d / r 6 layers c / r / d / e / d / c, r / c / d / e / d
/ C c / r / d / e / d / r, r / c / d / e / d / r 7 layers c / r / d / e / d / r / c, c / r / d / e /
d / c / rr r / c / d / e / d / c / r, r / c / d / e / d / r
/ C However, the layer structure is not limited to the above. Of these, preferred layer configurations include e / d / c and c /
d / e / d / c, c / r / d / e / b / c, etc. are shown.

When the resin composition layer composed of EVOH and the core-shell structure fine particles is laminated on the polyamide resin layer, in the above-mentioned layer constitution examples, various constitutions using a polyamide layer instead of the high-density polyethylene layer are used. No. In this case, unlike the case where a high-density polyethylene layer is used, the adhesive resin layer between the resin composition layer composed of EVOH and the core-shell structure fine particles and the polyamide resin layer may or may not be present. .

Although the thickness of each of these layers is not particularly limited, a preferred thickness for use as a fuel container is a high-density polyethylene layer or a polyamide layer 300.
0-10000μ, more preferably 4000-6000
μ, adhesive resin layer 20 to 1000 μ, more preferably 50
~ 300μ, composition layer composed of EVOH and core-shell structure fine particles 5 ~ 1000μ, more preferably 60 ~ 800μ
It is. The total thickness is 3000 to 10000μ, more preferably 4000 to 7000μ. These thicknesses refer to the thickness of the body of the fuel tank. Further, a suitable thickness when used as a fuel pipe must be appropriately adjusted according to the diameter of the pipe, but a preferable thickness ratio of each layer is the same as that of the fuel container.

The method for obtaining the fuel container and the fuel pipe having the multilayer structure of the present invention is not particularly limited. For example, a molding method practiced in the field of general polyolefins, for example, T-die molding , Blow molding, stamping molding, blow molding, injection molding, etc., and in particular, co-extrusion sheet molding, co-extrusion pipe molding, co-extrusion molding, co-extrusion blow molding, etc., and particularly co-extrusion blow molding. The method is preferred.

In the present invention, the fuel container is a fuel container mounted on an automobile, a motorcycle, a ship, an aircraft, a generator, and industrial or agricultural equipment, or a portable container for replenishing the fuel container with fuel. Further, it means a container for storing fuel used for these operations.
A fuel pipe is a pipe attached to a fuel container mounted above or a portable container for replenishing fuel to these fuel containers, and a container for storing fuel used for these operations. Etc. or a pipe independent of itself. Gasoline blended with gasoline, methanol and / or MTBE is a typical example of the fuel.
Other heavy oils, petroleum, petroleum and the like are also exemplified. Among them, the fuel container or pipe of the present invention is particularly effective for gasoline blended with methanol and / or MTBE.

In the present invention, the following additives may be added to each layer forming the multilayer structure. Examples of such additives include antioxidants, plasticizers, heat stabilizers, ultraviolet absorbers, antistatic agents, lubricants, colorants, fillers, and the like. Specific examples of the additives include the following.

Antioxidants: 2.5-di-t-butylhydroquinone, 2.6-di-t-butyl-p-cresol, 4.4'-thiobis- (6-t-butylphenol), .2'-methylene-bis- (4-methyl-6-
t-butylphenol), octadecyl-3- (3 ′.
5'-di-t-butyl-4'-hydroxyphenyl) propionate, 4.4'-thiobis- (6-t-butylphenol) and the like. UV absorber: ethylene-2-cyano-3.3'-diphenylacrylate, 2- (2'-hydroxy-5'-
Methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-5′-methylphenyl)
Benzotriazole, 2- (2'-hydroxy-3'-
t-butyl-5'-methylphenyl) 5-chlorobenzotriazole, 2-hydroxy-4-methoxybenzophenone, 2.2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-oxybenzobenzophenone and the like.

Plasticizer: dimethyl phthalate, diethyl phthalate, dioctyl phthalate, wax, liquid paraffin, phosphate ester, etc. Antistatic agents: pentaerythritol monostearate, sorbitan monopalmitate, sulfated polyolefins,
Polyethylene oxide, carbowax, etc. Lubricants: ethylene bis stearamide, butyl stearate and the like. Colorants: carbon black, phthalocyanine, quinacridone, indoline, azo pigments, red iron, etc. Filler: glass fiber, asbestos, ballastonite, calcium silicate, etc.

EVOH (a) includes hydrotalcite-based compounds, hindered phenol-based, hindered amine-based heat stabilizers, metal salts of higher fatty acid carboxylic acids (for example, calcium stearate, magnesium ) Is preferably added in an amount of 0.01 to 1% by weight.

[0052]

EXAMPLES Examples and comparative examples are shown below. Example 1 EVOH containing 350 ppm of sodium acetate ｛amount of ethylene of 32 mol%, degree of saponification of 99.6%, MI = 3.0
g / 10 minutes (210 ° C, 2160g load) @ 85% by weight
And resin fine particles having a core-shell structure ｛core component: 7
0 wt%: polybutyl acrylate: Tg = −39 ° C. /
Shell component: 30% by weight: polymethyl methacrylate:
Tg = 106 ° C, manufactured by Takeda Pharmaceutical “Staphyroid IM10
1) After dry blending with 15% by weight, 30mm
The mixture was melt-kneaded at a cylinder temperature of 230 ° C. using a φ twin-screw extruder and pelletized.

Using these pellets as an intermediate layer, high-density polyethylene (HDPE) @ MI = 0.025 g / 10 min (2
10 ° C., 2160 g load), density 0.96 g / cm ³ ,
“HZ8200B” manufactured by Mitsui Petrochemical Co., Ltd. was used as the outer layer, and the adhesive resin layer (AD) was further modified with maleic anhydride-modified polyethylene {MI = 1.8 g / 10 min (210 ° C., 216
0g load), 3 types and 5 layers (inner HDP) by co-extrusion blow molding using Mitsui Petrochemical "Admer GT4"
E / AD / resin composition / AD / outer layer HDPE = 1163
/ 50/75/50 / 1163μ) was obtained.

As a test of the barrier properties, 300 cc of model gasoline (A) [gasoline {common petroleum: lead-free regular} (85 vol%) mixed with methanol (15 vol%)] was poured into the multilayer container, and no leakage occurred. And then left in an explosion-proof constant temperature / humidity layer (20 ° C.-65% RH) to measure the weight loss after 4 days (average value of n = 6). Next, as an impact resistance test,
Water was filled and dropped on concrete, and the drop height at which the bottle was broken (water inside the container leaked) was determined. For the breaking height, a 50% breaking height was determined by using the calculation method shown in the JIS test method (part of “8. Calculation” of K7211) using the test result of n = 30. Table 1 shows the measurement results of these barrier properties and impact resistance.

Examples 2 and 3 and Comparative Examples 1 and 2 A multilayer container having the same configuration under the same conditions as in Example 1 except that the resin composition layer of the multilayer container was changed as shown in Table 1. Then, a barrier and bottle drop test was performed, and the results are shown in Table 1.

Example 4 Resin fine particles having the same core-shell structure as in Example 1 having 85% by weight of EVOH and a shell portion modified with itaconic acid {core component: 70 wt%: polybutyl acrylate: T
g = -39 ° C./shell component: 30 wt%: itaconic acid-modified polymethyl methacrylate: Tg = 112 ° C., dry blended with Takeda Pharmaceutical “Staphyroid IM301” @ 15% by weight, and then a 30 mmφ twin screw extruder. The mixture was melt-kneaded and pelletized to obtain a 500 cc multilayer container under the same conditions as in Example 1, and the barrier properties and impact resistance were evaluated in the same manner as in Example 1. The results are summarized in Table 1.

Example 5 In Example 2, the model gasoline (A) was replaced with the model gasoline (B) [gasoline {common petroleum: unleaded regular}.
(100% by volume)], and the barrier property and bottle drop test were performed in the same manner as in Example 2 except that the barrier measurement period was changed to 6 months. The results are shown in Table 1.

Comparative Example 3 In Comparative Example 1, the model gasoline (A) was replaced with the model gasoline (B) [gasoline {common petroleum: unleaded regular}.
(100% by volume)], and the barrier property and bottle drop test were performed in the same manner as in Example 1 except that the barrier measurement period was set to 6 months. The results are shown in Table 1.

[0059]

[Table 1]

Example 6 The same resin composition comprising EVOH and fine particles having a core-shell structure as in Example 1 was applied to a co-extrusion multilayer pipe molding apparatus to produce a multilayer pipe. The structure of the pipe was 12 polyamide@MI=0.7 g / 10 min (2
(10 ° C, 2160 g load), 450 µm of “UBE nylon 3035” manufactured by Ube Industries, and maleic anhydride-modified polyethylene {MI = 3.5 g / 10 min (21
0 ° C, 2160g load), "Admer V" manufactured by Mitsui Petrochemical
F500 "} is 50μ and further 6 polyamide layers {MI =
2.3 g / 10 min (230 ° C., 2160 g load), “Amilan CM1046” manufactured by Toray Co., Ltd. is 100 μm, the resin composition layer is 150 μm, and the innermost layer is “Amilan CM” manufactured by Toray
1046 "250μ. The thus obtained 4 kinds and 5 layers (outer layer 12 polyamide / adhesive resin layer / 6 polyamide / resin composition layer / inner layer polyamide 6 = 450/50/1)
(00/150 / 250μ) A pipe having an outer diameter of 10 mm was obtained. In order to measure the barrier properties, the obtained pipe was plugged at the end of the end, and the same model gasoline as in Example 1 was poured, and the weight loss one month later was measured. Meanwhile,
For the impact test, a four-type, five-layer sheet having the same thickness and the same structure as the above-mentioned pipe was produced by the co-extrusion molding method.
Impact resistance was measured by STM-D3029 (-40 ° C). Table 2 shows the results of these barrier properties and impact resistance.

Comparative Example 3 A barrier and bottle drop test was performed under the same conditions as in Example 6 except that the resin composition layer of the multilayer container was changed as shown in Table 2. It was shown to.

[0062]

[Table 2]

[0063]

The fuel container and the fuel transfer pipe of the present invention have excellent gasoline barrier properties, especially excellent oxygen-containing gasoline barrier properties, and also excellent impact resistance.

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Claims (6)

[Claims] 1. A fuel container or fuel pipe comprising a multilayer structure having a resin composition layer comprising a saponified ethylene-vinyl ester copolymer (a) and resin fine particles (b) having a core-shell structure. 2. A resin composition layer according to claim 1, comprising a saponified ethylene-vinyl ester copolymer (a) (60% by weight) and resin fine particles having a core-shell structure (b) 1 to 40% by weight. Fuel container or fuel pipe. 3. The glass transition temperature of the resin of the core component of the resin fine particles (b) having a core-shell structure is -10 ° C. or lower, and the glass transition temperature of the shell component is 30 ° C. or higher. Fuel container or fuel pipe. 4. A resin composition layer and a high-density polyethylene layer which are laminated via an adhesive resin layer.
A fuel container or a fuel pipe according to any one of the above. 5. The fuel container or fuel pipe according to claim 1, wherein a resin composition layer and a polyamide resin layer are laminated. 6. The fuel container or fuel pipe according to claim 1, which is for oxygenated gasoline.