JP2002048272A - Fuel pipe or tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel pipe or tank which hardly causes stress crackings due to fuel, particularly due to gasoline and is superior to barrier properties with respect to gasoline. SOLUTION: This fuel pipe or tank is applied to gasoline or the like, comprised of a multi-layer construction including at least one layer of the composition layer (C), made by blending a polyolefin resin (B) 1 to 50 pts.wt. to an ethylene vinyl alcohol copolymer (A) 100 pts.wt. of ethylene content 10 to 80 mol.%, and further, by blending a hydrophobic plasticizer (F).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel pipe or tank having an EVOH resin composition layer, which is excellent in stress crack resistance and gasoline gas barrier properties against gasoline, particularly oxygen-containing gasoline.

[0002]

2. Description of the Related Art Plastics are expected in many fields as materials for containers for storing hydrocarbons, for example, gasoline or pipes for transferring gasoline, such as fuel tanks for automobiles and fuel pipes. . In addition, polyethylene (especially, ultra-high-density polyethylene) is expected as a plastic in terms of economy, moldability, mechanical strength, and the like. However, polyethylene fuel tanks are known to have the disadvantage that stored gasoline gases or liquids tend to scatter into the atmosphere through the polyethylene wall of the container. Therefore,
In order to solve such a drawback, a method of blowing halogen gas (fluorine, chlorine, bromine, etc.) or sulfur trioxide (SO ₃ ) into a polyethylene container to halogenate or sulfonate the inner surface of the container has been proposed. A method of forming a multilayer of a resin and a polyethylene resin has been devised, and some methods have been put to practical use. However, even in the polyethylene container treated by the above-described method, alcohols having a low boiling point such as methyl alcohol and ethyl alcohol, or methyl-t-butyl ether (Methyl-t-butyl ether) have recently been used in order to save gasoline, improve performance, and improve the global environment. MTB
Oxygen-containing gasoline blended with ethers such as E), water-mixed gasoline and water-mixed oxygen-containing gasoline that are practically unavoidable when using a fuel tank have the disadvantage that the permeation amount increases. It is desired to improve these disadvantages.

[0003] As a further improvement, attention has been paid to an ethylene-vinyl alcohol copolymer (hereinafter abbreviated as "EVOH") as a material having very low permeability (good barrier properties) for gasoline and oxygenated gasoline. And a multilayer container in which EVOH and polyethylene are laminated, a multilayer pipe in which EVOH and polyamide are laminated, and the like are being experimentally manufactured. Also, Japanese Patent Application Laid-Open
No. 103528 discloses an ethylene copolymer (DuPont) in which a hollow molded container or a tubular container having two layers, one layer is formed of polyolefin and the other layer is mainly EVOH and contains metal ions. It is introduced that a hollow molded container or a tubular container formed of a resin composition comprising three components of Surlyn) and nylon has low gasoline permeability and excellent oil resistance.

As a result, these multilayer structures have good barrier properties against gasoline and oxygen-containing gasoline, and have been actively studied for practical use. However, there are unexpected large problems. found. That is, for example, ultra high density polyethylene (UHDPE) / adhesive resin (A
d) In a fuel tank of a three-layer, five-layer structure with three layers of / EVOH / Ad / UHDPE, when various types of gasoline are filled and stored for a long period of time, minute cracks may occur in a part of the tank, or the gasoline barrier property may be rapidly deteriorated. There are cases.
As a result of investigating various causes, the gasoline swellability (dimensional change rate) of UHDPE and Ad and the gasoline swelling (rate of dimensional change) differ greatly from that of EVOH when filling gasoline, and abnormal stress is applied to EVOH.
H was found to easily cause stress cracks in oxygenated gasoline and moisture-containing oxygenated gasoline. therefore,
One of the important issues is the development of EVOH having excellent stress crack resistance to gasoline, particularly oxygen-containing gasoline, and excellent gasoline barrier properties.

[0005]

The present invention relates to gasoline,
In particular, it is intended to provide a fuel pipe or tank having gasoline barrier properties using an EVOH resin composition excellent in stress crack resistance against oxygen-containing gasoline and gasoline barrier properties.

[0006]

The above object is achieved by blending 1 to 50 parts by weight of a polyolefin resin (B) with 100 parts by weight of EVOH (A) having an ethylene content of 10 to 80 mol%, By providing a fuel pipe or tank having at least one layer of the composition (C) containing the agent (F), the composition (C) layer and the thermoplastic resin (D) layer can be adhered to each other. This is achieved by providing a fuel pipe or tank comprising a multilayer structure laminated via a resin (E) layer. The present inventors evaluated the stress cracking property and the gasoline barrier property against gasoline under a 10% constant tensile strain condition using a film obtained by blending various thermoplastic resins and the like with EVOH. As a result, when the polyolefin resin (B) and the hydrophobic plasticizer (F) are blended with the EVOH (A), stress cracks are improved, that is, gasoline stress cracks are not generated under 10% constant tensile strain conditions. I found that.

In the present invention, as the polyolefin resin (B), polyethylene; polypropylene; ethylene and propylene, vinyl acetate, acrylate,
Copolymers of vinyl monomers such as methacrylic acid ester, acrylic acid and methacrylic acid; polyolefins obtained by copolymerizing or graft-polymerizing these with acid anhydrides, vinylsilane compounds or epoxy group-containing compounds; ethylene content of 40 to 95 mol% And saponified ethylene-vinyl acetate copolymer having a saponification degree of 50% or more.

When a polyolefin resin is blended, E
Good thermal stability of the composition (C) with the VOH (A) and prevention of deterioration of the stress crack resistance due to generation of gels and lumps even when the molding machine is operated for a long time at the time of forming a film or the like. Can be.

In the present invention, EVOH (A) is a saponified ethylene-vinyl ester copolymer having an ethylene content of 10 to 80 mol%, preferably 20 to 7 mol%.
The range is 0 mol%, and the saponification degree is selected from 80% or more, preferably 85% or more. Ethylene content is 20 mol%
If less than 80 mol%, the melt moldability is poor.
Insufficient gas barrier properties. On the other hand, when the saponification degree is less than 80%, the gas barrier property and the thermal stability deteriorate. In the present invention, vinyl acetate is a typical vinyl ester used in the production of EVOH, but other fatty acid vinyl esters (such as vinyl propionate and vinyl pivalate) can also be used.

[0010] Even when EVOH contains 0.0002 to 0.2 mol% of a vinylsilane compound as a copolymerization component, the consistency of the melt viscosity between the substrate and the EVOH is improved, and a homogeneous coextruded multilayer film is obtained. Not only can be produced, but also the dispersibility is improved when EVOH is blended with each other, which is effective in improving moldability and the like.

Here, as the vinylsilane-based compound,
Examples include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (β-methoxy-ethoxy) silane, and γ-methacryloxypropylmethoxysilane. Among them, vinyltrimethoxysilane and vinyltriethoxysilane are preferably used.

Further, other comonomer such as propylene, butylene, unsaturated carboxylic acid or ester thereof (meth) acrylic acid, as long as the object of the present invention is not hindered,
(Meth) acrylic acid esters (methyl, ethyl) etc., vinylpyrrolidone (N-vinylpyrrolidone, etc.)
Can be copolymerized, and further, a heat stabilizer, an ultraviolet absorber, an antioxidant, a colorant, a filler, and a boron compound can be blended. In particular, hydrotalcite-based compounds, hindered phenol-based, hindered amine-based heat stabilizers, metal salts of higher aliphatic carboxylic acids (for example, calcium stearate, magnesium stearate, etc.) are used to prevent gel formation, improve moldability, and prevent cracks. ) Or one or more boron-based compounds is preferably added in an amount of 0.01 to 1% by weight.

Further, a preferable melt index (MI) of the EVOH used in the present invention (value measured at 190 ° C. under a load of 2160 g; if the melting point is around 190 ° C. or exceeds 190 ° C., the melt index is higher than the melting point under a load of 2160 g. At a plurality of temperatures, and plotting the reciprocal of the absolute temperature on the horizontal axis and the melt index on the vertical axis on a semi-log graph,
(Value extrapolated to 90 ° C.) is 0.1 to 50 g / 10 m
in. , Optimally 0.5 to 20 g / 10 min. It is.

Examples of the polyolefin resin (B) include polyethylene; polypropylene; a copolymer of ethylene and propylene, vinyl acetate, acrylic ester, methacrylic ester, acrylic acid, methacrylic acid, etc .; , Its acid anhydrides,
An acid anhydride, a vinylsilane-based compound, or a modified polyolefin-based resin obtained by copolymerizing or graft-polymerizing a vinylsilane-based compound or an epoxy group-containing compound, which is effective for improving compatibility and dispersibility with EVOH (A). Modified polyolefin-based resin obtained by copolymerizing or graft-polymerizing an epoxy group-containing compound is preferable, among which acid anhydride or epoxy group-containing resin is used, and as the resin, high-density polyethylene and ethylene-propylene copolymer are used. More preferred.

Other polyolefin resins (B) include:
Examples include saponified ethylene-vinyl acetate copolymers having an ethylene content of 40 to 95 mol% and a degree of saponification of 50% or more. When the ethylene content of the saponified ethylene-vinyl acetate copolymer is 40% or less, the effect of improving stress crack resistance is not sufficient, while when it is 95% or more, mechanical strength due to deterioration of compatibility with EVOH is insufficient. And the gasoline barrier property deteriorates. As a general tendency, it is desirable that the ethylene content is low, preferably 44 to 90 mol%.
If the saponification degree is 50% or less, the thermal stability is poor and it is not preferable from the viewpoint of compatibility. As a general tendency, the degree of saponification is preferably low, and more preferably 60% or more. It is desirable that the EVOH (A) be at least 5 mol%, more preferably 10 mol%, larger than the ethylene content.

The compounding amount of the polyolefin resin (B) is E
1 to 50 parts by weight with respect to 100 parts by weight of VOH (A)
Preferably, it is 5 to 40 parts by weight. If the amount is less than 1 part by weight, the effect of improving stress crack resistance is not sufficient. On the other hand, if it exceeds 50 parts by weight, the gasoline barrier property is not sufficient.

In the present invention, it is necessary to add a hydrophobic plasticizer (F) to the composition comprising (A) and (B). Here, as the hydrophobic plasticizer (F), those satisfying the following expression are more preferable. 6.5 ≧ 19−CH (A) × 0.1−SP (F) ≧ 1.5 (i) −1 ≦ SP (F) −SP (B) ≦ 3.5 ... (ii) [where CH (A) is the average ethylene content (mol%) of EVOH (A), and SP (F) is the solubility parameter of hydrophobic plasticizer (F) (Fedors equation) , SP
(B) shows the solubility parameter (Fedros equation) of the polyolefin resin (B). ]

The cause of the unexpected improvement effect due to the addition of the hydrophobic plasticizer (F) is not clear, but the stress crack resistance is determined by adding the amount of the polyolefin resin (B) by adding the hydrophobic plasticizer (F). What can be greatly reduced, that is,
Hydrophobic plasticizer (F) is more polyolefin resin (B) than EVOH resin (A) due to solubility (parameter).
It is presumed that the stress crack resistance was improved by plasticizing the polyolefin resin (B).

Examples of the hydrophobic plasticizer (F) include aromatic esters, aliphatic esters, phosphate esters, and epoxy compounds thereof.

As the aromatic ester, dibutyl phthalate, dioctyl phthalate, diheptyl phthalate,
Di (2-ethylhexyl) phthalate, dicyclohexyl phthalate, butyl lauryl phthalate, diisooctyl phthalate, butyl coconut alkyl phthalate, ditridecyl phthalate, dilauryl phthalate,
Diisodecyl phthalate, butylbenzyl phthalate,
Octylcapryl phthalate, dimethyl glycol phthalate, ethyl phthalyl ethylene glycolate, methyl phthalyl ethylene glycolate, butyl phthalyl butylene glycolate, dinonyl phthalate, octyl decyl phthalate, dicapryl phthalate, di (3,5,5-
Trimethylhexyl) phthalate, isooctyl isodecyl phthalate, dimethoxyethyl phthalate, dibutoxydiethyl phthalate, bis (diethylene glycol monomethyl ether) phthalate and the like.

Examples of the aliphatic ester include polypropylene adipate, diisodecyl adipate, di (2-methylhexyl) adipate, dicapryl adipate, diisooctyl adipate, octyl decyl adipate, isooctyl isodecyl adipate, dibutyl fumarate,
Examples include dioctyl fumarate, triethyl citrate, acetyl triethyl citrate, tributyl citrate, acetyl tributyl citrate, and acetyl tri (2-ethylhexyl) citrate.

Examples of the phosphoric acid ester include tricresyl phosphate, phenyldicresyl phosphate, xyenyl dicresyl phosphate, cresyl dixylenyl phosphate, triphenyl phosphate, tributyl phosphate, and trichloroethyl phosphate. , Trioctyl phosphate, triethyl phosphate, allyl alkyl phosphate, diphenyl monoorthoxenyl phosphate and the like.

Epoxy compounds include epoxy monoester, butyl epoxy stearate, octyl epoxy stearate, epoxy butyl oleate, epoxidized butyl oleate, epoxidized soybean oil, epoxidized linseed oil, epoxidized alkyl oil, epoxy Alkylated alcohol esters and the like.

Among them, epoxidized soybean oil, epoxidized linseed oil, di (2-methylhexyl) adipate, diisooctyl adipate, dibutyl phthalate, diethyl phthalate, di (2-ethylhexyl) phthalate, methyl phthalyl ethylene glycolate, etc. It is preferably used.

The MI of the composition obtained by blending the hydrophobic plasticizer (F) with the composition of the EVOH (A) and the polyolefin resin (B) at 190 ° C. under a load of 2160 g is 0.1%.
５０50 g / 10 min. Preferably, 0.3 to 30 g / 1
0 min. It is.

The method of blending (A) and (B), and (F) therewith is not particularly limited, but EVOH and the thermoplastic resin are dry-blended and used as they are. Alternatively, more preferably, there is a method of pelletizing and drying with a Banbury mixer, a single screw or twin screw extruder, or the like. There is a high possibility that cracks will occur if the blend is non-uniform or if there is gel or lumps during the pelletizing operation. Therefore, it is desirable to extrude at a low temperature by using an extruder having a high kneading degree during the blend pelletizing operation, sealing the hopper port with N ₂ , and extruding at a low temperature. In addition, when forming a blend pellet, other additives (such as a plasticizer, a heat stabilizer, an ultraviolet absorber, an antioxidant, a colorant, a filler, a boron-based compound, and other resins) are not impaired for the purpose of the present invention. It is free to use in the range. In particular, as a measure for preventing gel formation, one or more of a hydrotalcite-based compound, a hindered phenol-based, a hindered amine-based heat stabilizer, and a metal salt of a higher aliphatic carboxylic acid (for example, calcium stearate) are used in an amount of 0.01 to 0.2%. It is preferable to add 1% by weight.

The fuel pipe or tank of the present invention comprises a composition (C) obtained by mixing (A) and (B) with (F).
Has at least one layer, but a layer obtained by laminating another thermoplastic resin (D) layer on the composition (C) layer is preferable. The thickness of the composition (C) layer that imparts gas barrier properties and gasoline barrier properties is selected from the range of 5 to 250 µ, usually 10 to 100 µ. On the other hand, as the thermoplastic resin (D) used for the inner layer and / or the outer layer, an arbitrary one is adopted, and there is no particular limitation. Depending on the purpose, consideration should be given to points such as moisture permeability, heat resistance, and heat sealability. Thus, a multilayer structure having excellent gasoline barrier properties can be obtained. Examples of the thermoplastic resin (D) include polypropylene, polyolefin resin, polyamide resin, polyester resin, polystyrene resin, polyvinyl chloride resin, acrylic resin, polyvinylidene chloride resin, polyacetal resin, and polycarbonate resin. , Polyurethane resin and irradiation-crosslinked polypropylene, polyethylene, ethylene-vinyl acetate copolymer, saponified ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene- Acrylic ester-based copolymers, ethylene-methacrylic ester-based copolymers and the like can be mentioned, among which high-density polyethylene, polypropylene and polyamide are preferably used. Further, additives such as an antioxidant, a colorant, and a filler as described above may be added to the resin used for both outer layers.

In the present invention, when laminating the composition (C) and the thermoplastic resin (D), it is preferable to use an adhesive resin (E) in order to improve stress cracking. The adhesive resin (E) is not particularly limited as long as it strongly adheres the composition (C) layer and the thermoplastic resin (D) layer. An anhydride (eg, maleic anhydride) is an olefin polymer such as polypropylene or polyethylene, or a copolymer of ethylene and a monomer capable of copolymerizing it (eg, vinyl acetate, acrylate) [eg, ethylene-vinyl acetate copolymer]. Polymer, ethylene- (meth) acrylate (methyl ester or ethyl ester)
Copolymer] is preferably used.

The multilayer structure can be obtained by extrusion lamination, dry lamination, coextrusion lamination, coextrusion molding of the composition (C) and the thermoplastic resin (D) via the adhesive resin (E). A method of obtaining a film-like, sheet-like, pipe-like, tank (including bottle) -like structure, particularly a multilayer structure, by a method, a co-injection molding method, a co-extrusion inflation molding method, or a solution coating method. When this structure is obtained, the structure can be reheated within the range of the melting point of EVOH or less, and can be uniaxially or biaxially stretched by a roll stretching method, a pantograph stretching method, an inflation stretching method, a blow stretching method, or the like. . Further, the composition (C) layer and the thermoplastic resin (D) layer are cross-linked by irradiating the multilayer structure with radiation, electron beam, ultraviolet ray, or the like. You can also.

Regarding the thickness structure of the multilayer structure, considering the moldability and cost, etc.,
The thickness ratio of the H composition layer is preferably about 2 to 20%.
The positional relationship between the composition (C) layer of the intermediate layer and the thermoplastic resin (D) layer in both outer layers or outer layers greatly affects the barrier properties and stress crack resistance, and is inside the tank or pipe, that is, When the layer in contact with fuel such as gasoline is the inner layer and the layer in contact with the outside air is the outer layer, the stress crack resistance is improved as the composition (C) layer is located on the inner side, and depending on the brand of gasoline. May deteriorate the barrier properties. Conversely, the closer the composition (C) layer is to the outer layer, the worse the stress crack resistance is, but the better the gasoline barrier properties may be. Therefore, it is generally desirable that the composition (C) layer not be located at the center between the outer layer and the inner layer. The structure of the multilayer structure is as follows: EVOH composition (C) layer / adhesive resin (E) layer / thermoplastic resin (D) layer; thermoplastic resin (D) layer / adhesive resin (E) layer / EVOH Typical examples are a composition (C) layer, a thermoplastic resin (D) layer / adhesive resin (E) layer / EVOH composition (C) layer / adhesive resin (E) layer / thermoplastic resin (D) layer. I can do something. When a polyolefin resin layer is provided on both outer layers, the resins may be different or the same. In many cases, scrap such as trim generated during molding is blended with the thermoplastic resin layer, or a separate recovery layer is provided for reuse.

Here, the fuel pipe means a gasoline supply pipe, a gasoline transfer pipe used for an automobile, an oil supply pipe, an oil transfer pipe used for an oil stove, and the like. The fuel tank refers to a gasoline storage tank, a storage bottle, a gasoline tank used for an automobile, an oil storage tank, a storage bottle, a storage tank used for an oil stove, and the like.

As described above, these pipes or tanks can be obtained by a co-extrusion method, a co-injection method, or the like. However, it is also possible to obtain a film or sheet, and use them to obtain a pipe or a tank. it can.

[0033]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto.

Example 1 Ethylene content 27 mol%, degree of saponification 99.5%, mel
Toindex (MI 190 ° C, 2160g load)
5 g / 10 min. 100 parts by weight of EVOH (A)
GMA (glycidyl meta) as the reolefin resin (B)
(Acrylate) modified HDPE (high density polyethylene, S
P (B) = 8.6) 10 parts by weight and a hydrophobic plasticizer
GMS (glycerin monostearate, S
P (F) = 10.2) 4 parts by weight of twin screw tie
, Put into vent type 40Φ extruder, N ²Atmosphere, 20
Extrusion pelletization was performed at 0 ° C. Obtained resin (C)
Has a melt viscosity index (MI) of 1 g / 10 min. Met.
The pellets were put into a single-layer film forming apparatus,
Obtain a film and pull it 10% using JIS dumbbell No.3
40 ° C gasoline (commercial regular gasoline)
(Phosphorus) for 3 hours to evaluate stress cracking
However, no crack was observed. In addition, the pellet
3 types 5 layers coextrusion multilayer direct blow device
A multi-layer container was created. The composition of the seats is the outermost layer
Polyethylene resin layer (manufactured by Mitsui Petrochemical Co., Ltd.
HZ8200B) 850μ each and adhesive resin layer
(Mitsui Petrochemical Admar NF450A)
μ, and the EVOH composition (C) layer in the center of the innermost layer
100μ. Fill the resulting container with gasoline and add 40
C.-65% RH for 1 year.
No deterioration in sorin barrier properties was observed. Accelerated test
The body of the container was cut off as
10% tensile elongation using JIS dumbbell No. 3
Originally immersed in 40 ° C gasoline for 3 hours and stress cracked
Evaluation of the properties revealed no cracks. Ma
The gasoline barrier property of the container was 0.020 g /
m². It was day.

Example 2 The polyolefin resin (B) used in Example 1 was replaced with H
Stress cracking properties and gasoline barrier of single-layer films and multilayer containers manufactured according to Example 1 using DPE (high-density polyethylene, SP (B) = 8.6) and Ref-C gasoline instead of commercial regular gasoline The properties were measured. Table 1 shows the results.

Example 3 In place of the polyolefin resin (B) used in Example 1, maleic anhydride-modified HDPE (high-density polyethylene, SP
(B) = 8.6) and G as hydrophobic plasticizer (F)
Instead of MS, diethyl phthalate (DEP, SP
Example 1 using (F) = 10.5) and using Ref-C gasoline instead of commercial regular gasoline.
Operation was repeated. Table 1 shows the results.

Example 4 In place of the polyolefin resin (B) used in Example 1, S
i-modified ethylene-propylene copolymer (SP (B) =
8.4) and GMS as hydrophobic plasticizer (F)
The procedure of Example 1 was repeated using DEP instead of, and using MTBE15 gasoline instead of commercial regular gasoline. Table 1 shows the results.

Example 5 Using the EVOH composition (C) used in Example 1, 4 types 5
The multilayer co-extruded multilayer pipe molding apparatus was used to produce a multilayer pipe. The configuration of the pipe is 450μ for the outermost layer 12 polyamide (Ube Nylon Co., Ltd. UBE nylon 3020μ),
Adhesive resin layer is 50μ each, 6 polyamide (Amilan CM1046 manufactured by Toray Industries, Inc.) 100μ, EVO
The H composition (C) layer is 150 μm, and the innermost layer is 6 polyamide (Amilan CM1046 manufactured by Toray Industries, Inc.) 250 μm. Attach a metal fitting to the end of the obtained pipe,
(Radius) = 30cm, wound in a loop, gasoline (M-
15) and left under a condition of 40 ° C.-65% RH for 1 year, but no cracks or deterioration in gasoline barrier properties were observed. As an accelerated test, the body of the pipe was cut into a ring, and a 10 mm tensile elongation was applied to the pipe so that it could be expanded with a cylindrical jig having an outer diameter 10% longer than the circumference of the inner diameter of the pipe (10%). 40 ° C M)
The sample was immersed in -15 gasoline for 3 hours to evaluate stress cracking, but no crack was observed. The gasoline barrier property of the pipe is 0.2 g / m ² · day.
Met.

Comparative Example 1 Pellets were produced from the EVOH (A) used in Example 1 by using a twin screw type, vented 40 Φ extruder. A layer film was produced. Using the pellets, a multilayer container was produced in the same manner as in Example 1 by a three-type five-layer coextrusion direct blow apparatus. Table 1 shows the results of measuring the stress cracking property and gasoline barrier property of the single-layer film and the multilayer container with respect to the Ref-C mixed gasoline in the same manner as in Example 2.

Comparative Example 2 In place of the hydrophobic plasticizer (F) used in Example 1, glycerin (Gly, SP (F)) which is a hydrophilic plasticizer was used.
The operation of Example 1 was repeated using 4). Table 1 shows the results.

[0041]

[Table 1]

(Note) The symbols in Table 1 are as follows. (1) Brand of polyolefin resin (B) A Glycidyl methacrylate-modified HDPE (high-density polyethylene) B Maleic acid-modified HDPE C Silicon (Si) -modified ethylene propylene copolymer D HDPE (high-density polyethylene) (2) Hydrophobic plastic Brand of Agent (F) GMS Glycerin Monostearate DEP Diethylphthalate Gly Glycerin (Hydrophilic Plasticizer) (3) Brand of Thermoplastic Resin Constituting Multilayered Structure HDPE HIZEX HZ manufactured by Mitsui Petrochemical Co., Ltd.
8200B 6PA Alamine CM1046 12PA manufactured by Toray Industries, Inc. UBE nylon 302 manufactured by Ube Industries, Ltd.
00 AD-1 ADMER NF4 manufactured by Mitsui Petrochemical Co., Ltd.
50A AD-2 ADMER VF5 manufactured by Mitsui Petrochemical Co., Ltd.
00 (4) Gasoline brand Gasoline Commercial regular gasoline Ref-C Toluene (50% by volume) + isooctane (50% by volume) M-15 Ref-C (85% by volume) + methanol (15% by volume) MTBE15 Ref-C ( 85% by volume) + methyl-t
-Butyl ether (15% by volume)

[0043]

The fuel pipe or tank of the present invention obtained as described above has excellent stress cracking resistance to gasoline, good gasoline barrier properties, and furthermore has gas barrier properties, fragrance retention properties, and the like. Excellent organic solvent resistance.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08K 5/00 C08K 5/00 C08L 23/26 C08L 23/26 29/04 29/04 C F02M 37/00 301 F02M 37/00 301J // (C08L 23/26 (C08L 23/26 23:00) 23:00) (C08L 29/04 (C08L 29/04 C 23:00) 23:00) F term (reference) 3E033 AA20 BA14 BB04 CA03 CA09 CA16 3H111 AA01 BA15 CB02 DB08 4F071 AA14 AA15X AA29X AA76 AE04 AH19 BB05 BB06 BC05 4F100 AK01C AK03A AK05D AK05E AK21A AK69A AL05A AR00B BA03 BA05 BA07 BA10A BA10C BA10D BA10E BA15 CA04A DA01 DA11 EH202 GB16 JB01 JB06A JB06H JB16C JD01 JL11B 4J002 BB032 BB052 BB062 BB082 BB122 BB221 BE031 CD163 EH046 EH136 EL026 EW046 FD026 GF00

Claims (8)

[Claims] 1. A polyolefin resin (B) is blended in an amount of 1 to 50 parts by weight with respect to 100 parts by weight of an ethylene-vinyl alcohol copolymer (A) having an ethylene content of 10 to 80 mol%. A fuel pipe having at least one layer of a composition (C) containing F). 2. 100 parts by weight of an ethylene-vinyl alcohol copolymer (A) having an ethylene content of 10 to 80 mol%, 1 to 50 parts by weight of a polyolefin resin (B) are blended, and a hydrophobic plasticizer (B) is further added. The composition (C) layer containing F) and the thermoplastic resin (D) layer are bonded to the adhesive resin (E).
A fuel pipe composed of a multilayer structure laminated with layers. 3. The fuel pipe according to claim 1, wherein the fuel is oxygen-containing gasoline. 4. A polyolefin resin (B) is blended in an amount of 1 to 50 parts by weight with respect to 100 parts by weight of an ethylene-vinyl alcohol copolymer (A) having an ethylene content of 10 to 80 mol%. In obtaining a multilayer structure obtained by laminating a composition (C) layer containing F) and a thermoplastic resin (D) layer via an adhesive resin (E) layer,
A method for producing a fuel pipe, comprising subjecting (C), (D) and (E) to multi-layer coextrusion. 5. A polyolefin resin (B) of 1 to 50 parts by weight is blended with 100 parts by weight of an ethylene-vinyl alcohol copolymer (A) having an ethylene content of 10 to 80 mol%, and a hydrophobic plasticizer ( A fuel tank having at least one layer of a composition (C) containing F). 6. A polyolefin resin (B) is blended in an amount of 1 to 50 parts by weight with respect to 100 parts by weight of an ethylene-vinyl alcohol copolymer (A) having an ethylene content of 10 to 80 mol%. The composition (C) layer containing F) and the thermoplastic resin (D) layer are bonded to the adhesive resin (E).
A fuel tank comprising a multilayer structure in which layers are stacked. 7. The fuel tank according to claim 5, wherein the fuel is oxygen-containing gasoline. 8. A polyolefin resin (B) is blended in an amount of 1 to 50 parts by weight with respect to 100 parts by weight of an ethylene-vinyl alcohol copolymer (A) having an ethylene content of 10 to 80 mol%. In obtaining a multilayer structure obtained by laminating a composition (C) layer containing F) and a thermoplastic resin (D) layer via an adhesive resin (E) layer,
A method for producing a fuel tank, comprising: (C), (D), and (E) being co-extruded in a multilayer.