JP2002249595A - Injection molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection-molded product utilizing the essential characteristics of a polyolefin resin, such as toughness and moldability, and having remarkably excellent resistance to chemicals and gas permeation. SOLUTION: Each of (a) polyolefin resin and (b) ethylene-vinyl alcohol copolymer is 55 to 95.
% By volume and 45 to 5% by volume in a resin phase separation structure observed by an electron microscope, wherein (a) a continuous phase composed of a polyolefin resin and (b) ethylene-vinyl alcohol An injection-molded article characterized by forming a phase structure composed of a band-shaped dispersed phase composed of a polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection-molded article having excellent resistance to gas and / or liquid permeation. In particular, specific permeation resistance obtained by forming a polyolefin resin and an ethylene-vinyl alcohol copolymer (hereinafter abbreviated as EVOH) into a specific phase structure,
The present invention relates to an injection molded article having moldability.

[0002]

2. Description of the Related Art Polyolefin resins such as polyethylene and polypropylene are widely used as general plastics in daily necessities, toys, mechanical parts, electric / electronic parts, automobile parts and the like. However, in recent years, resin products that require gas barrier properties (permeation resistance) for the purpose of preventing leakage of contents and preventing intrusion of outside air in order to ensure safety, storage stability, and environmental pollution prevention properties have been developed. It is increasing. In particular, in automobile fuel tanks, etc., conversion from metal to plastic has been actively studied in terms of lightness, ease of molding, freedom of design, ease of handling, etc., but safety, In order to ensure storage stability and further prevent environmental pollution, it is important to prevent the leakage of contents and the intrusion of outside air, and materials having permeation resistance are required. However, containers made of polyolefins such as polyethylene and polypropylene are the most common plastic containers.However, due to insufficient barrier properties against gasoline and specific oils, their use is often restricted. The improvement is desired.

As a method for improving this, there has been proposed a method in which a resin having a high barrier property is dispersed in a layer form in the above-mentioned polyolefin resin (for example, Japanese Patent Publication No. 60-14695, Japanese Patent Application Laid-Open No. 4-296331). The barrier properties are greatly improved. However, a method of dispersing a resin having a high barrier property disclosed in these in a layered manner employs extrusion molding, and further stretches the melt after extrusion to form a dispersed phase by the stress, thereby forming a layered state. It is premised that the product can be stretched as a product shape, and there is a problem that it is limited to a sheet or tube shape, and that the moldability is insufficient due to the limitation of the stretching ratio.

[0004]

The object of the present invention is to improve the barrier properties of a polyolefin resin, and to suppress the deterioration of properties such as toughness and moldability, which are essential characteristics of the polyolefin resin, and to improve the properties of the chemical solution and Injection-molded products with specifically improved gas barrier properties, especially polyolefin-EVO obtained by injection molding that is excellent in barrier properties, moldability, adhesiveness, and toughness, and can improve production stability and economic efficiency
It is intended to provide an H structure.

[0005]

The inventors of the present invention have studied to solve the above-mentioned problems, and as a result, a resin obtained by blending a polyolefin resin and EVOH in a specific amount and further blending an inorganic filler as necessary. The present inventors have found that the above problems can be solved by controlling the dispersion structure of the composition so that the EVOH component forms a band-like dispersed phase in the injection-molded article by injection molding, and arrived at the present invention.

That is, the present invention comprises a resin composition in which (1) (a) a polyolefin resin and (b) an ethylene-vinyl alcohol copolymer have a relationship of 55 to 95% by volume and 45 to 5% by volume, respectively. And a phase structure composed of (a) a continuous phase composed of a polyolefin resin and (b) a strip-shaped dispersed phase composed of an ethylene-vinyl alcohol copolymer in a resin phase separation structure observed by an electron microscope. The mixing ratio of (2) (a) the polyolefin resin and (b) the ethylene-vinyl alcohol copolymer is 60 to 75% by volume and 4 respectively.
The injection-molded article according to (1), wherein the polyolefin resin is (0) to 25% by volume, (3) (a) the polyolefin resin is polyethylene, or (2). (C) 0.5 to 200 parts by weight of the inorganic filler is added to 100 parts by weight of the polyolefin resin (a) and the ethylene-vinyl alcohol copolymer (b). The injection-molded article according to any one of the above (1) to (3), which comprises:
(5) An injection-molded article according to any one of (1) to (4), which is a container for transporting and / or storing a chemical solution or gas or an accessory thereof.

[0007]

Embodiments of the present invention will be described below. In the present invention, “weight” means “mass”.

The (a) polyolefin resin used in the present invention is a thermoplastic resin obtained by polymerizing or copolymerizing olefins such as ethylene, propylene, butene, isoprene and pentene. Specific examples include polyethylene, polypropylene, polystyrene, polyacrylate, polymethacrylate, poly 1-butene,
Homopolymers such as poly 1-pentene and polymethylpentene, ethylene / α-olefin copolymers, vinyl alcohol ester homopolymers, polymers obtained by hydrolyzing at least a part of vinyl alcohol ester homopolymers, [Polymer obtained by hydrolyzing at least a part of copolymer of (ethylene and / or propylene) and vinyl alcohol ester], [(ethylene and / or propylene) and (unsaturated carboxylic acid and / or Copolymer with Saturated Carboxylic Acid Ester) and [Copolymer of (Ethylene and / or Propylene) with (Unsaturated Carboxylic Acid and / or Unsaturated Carboxylic Ester)] Copolymer], a block copolymer of a conjugated diene and a vinyl aromatic hydrocarbon, and
A hydride of the block copolymer is used.

Among them, polyethylene, polypropylene, ethylene / α-olefin copolymer, [copolymer of (ethylene and / or propylene) and (unsaturated carboxylic acid and / or unsaturated carboxylic acid ester)], [ (Epylene and / or propylene) and (unsaturated carboxylic acid and / or unsaturated carboxylic acid ester) are preferred.

The ethylene / α-olefin copolymer referred to herein is a copolymer of ethylene and at least one α-olefin having 3 to 20 carbon atoms, and the above-mentioned ethylene / α-olefin copolymer has 3 to 20 carbon atoms. Specific examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene,
Decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene,
3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1- Pentene, 4-ethyl-1-hexene, 3-
Ethyl-1-hexene, 9-methyl-1-decene, 11
-Methyl-1-dodecene, 12-ethyl-1-tetradecene and combinations thereof. These α
-Among olefins, copolymers using α-olefins having 3 to 12 carbon atoms are preferred from the viewpoint of improving mechanical strength. This ethylene / α-olefin copolymer is α-
The olefin content is preferably 1 to 30 mol%, more preferably 2 to 25 mol%, and still more preferably 3 to 20 mol%.

Furthermore, non-e.g. 1,4-hexadiene, dicyclopentadiene, 2,5-norbornadiene, 5-ethylidene norbornene, 5-ethyl-2,5-norbornadiene, 5- (1'-propenyl) -2-norbornene and the like At least one of the conjugated dienes may be copolymerized.

The unsaturated carboxylic acid used in [copolymer of (ethylene and / or propylene) and (unsaturated carboxylic acid and / or unsaturated carboxylic acid ester)] is selected from acrylic acid and methacrylic acid. Or a mixture thereof, and examples of the unsaturated carboxylic acid ester include methyl ester, ethyl ester, propyl ester, butyl ester, pentyl ester, hexyl ester, heptyl ester, octyl ester, nonyl ester, and decyl ester of these unsaturated carboxylic acids. ,
Alternatively, a mixture thereof may be mentioned, but a copolymer of ethylene and methacrylic acid, and a copolymer of ethylene, methacrylic acid and acrylate are particularly preferable.

[0013] Among these polyolefin resins, low,
Medium and high density polyethylene, polypropylene, ethylene / α-olefin copolymers are preferred. More preferably, low, medium and high density polyethylene, particularly preferably
It is a high-density polyethylene having a density of 0.94 to 0.97 g / cm ³ .

The melt flow rate of the polyolefin resin (a) of the present invention (hereinafter abbreviated as MFR: ASTM)
D 1238) is preferably 0.01 to 70 g / 10 min, more preferably 0.03 to 60 g / 10 min.
Minutes. When the MFR is less than 0.01 g / 10 minutes, the fluidity is poor, and when it exceeds 70 g / 10 minutes, the impact strength is lowered, which is not preferable.

The method for producing the polyolefin resin (a) used in the present invention is not particularly limited, and may be any of radical polymerization, coordination polymerization using a Ziegler-Natta catalyst, anionic polymerization, and coordination polymerization using a metallocene catalyst. Can also be used.

In the present invention, it is preferable to use, as the polyolefin resin (a), a polyolefin resin having a part or all of its function as a compatibilizer. Here, “having a compatibilizing action” means an action of reducing the difference between two resins as a solubility parameter of Fedors. By using a polyolefin resin having such a compatibilizing action, the compatibility with EVOH is improved, the controllability of the phase separation structure of the obtained resin composition is improved, and as a result, excellent permeation resistance is exhibited. It shows features and is one of the preferred embodiments.

Examples of the polyolefin resin having such a function as a compatibilizer include an acid-modified polyolefin obtained by grafting an unsaturated dicarboxylic anhydride with a radical initiator and introducing an ethylene / unsaturated anhydride. Carboxylic acid copolymers and the like can be mentioned, and these can be used in combination of two or more kinds.

The unsaturated dicarboxylic anhydride used for the acid-modified polyolefin includes maleic anhydride, itaconic anhydride, citraconic anhydride, etc., and maleic anhydride is particularly preferred. Examples of the unsaturated carboxylic acid used in the ethylene / unsaturated carboxylic acid copolymer include acrylic acid and methacrylic acid, or a mixture thereof, and may partially include an unsaturated carboxylic acid ester.

The content of the polyolefin resin acting as a compatibilizer is preferably 0.5 to 50% by volume of the polyolefin resin (a). More preferably 1 to 40% by volume, particularly preferably 1 to 30% by volume
It is.

The (b) EVOH used in the present invention is obtained by, for example, saponifying a copolymer composed of ethylene and vinyl ester using an alkali catalyst or the like. A typical example of the vinyl ester is vinyl acetate, but other fatty acid vinyl esters (such as vinyl propionate and vinyl pivalate) can also be used. Also, E
VOH is a vinylsilane compound 0.00 as a copolymer component.
It can contain from 0.2 to 0.2 mol%. here,
Examples of the vinylsilane-based compound include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (β-methoxy-ethoxy) silane, and γ-methacryloxypropylmethoxysilane. Among them, vinyltrimethoxysilane and vinyltriethoxysilane are preferably used. Furthermore, as long as the object of the present invention is not inhibited, other comonomers, for example, propylene,
Butylene or an unsaturated carboxylic acid such as (meth) acrylic acid, methyl (meth) acrylate or ethyl (meth) acrylate or an ester thereof, and vinylpyrrolidone such as N-vinylpyrrolidone can also be copolymerized. .

In the EVOH used in the present invention, the ethylene fraction is preferably 20 to 60 mol%, more preferably 25 to 55 mol%, and still more preferably 25 to 50 mol%. If the ethylene content is less than 20 mol%, the improvement in barrier properties under high humidity tends to be low, and the moldability may be deteriorated. On the other hand, if it exceeds 60 mol%, the effect of improving the barrier properties may be reduced.

The degree of saponification of the vinyl ester component of EVOH used in the present invention is preferably 90% or more, more preferably 95% or more, and further preferably 98%.
That is all. If the saponification degree is less than 90%, it is difficult to obtain a material having a sufficient barrier property under high humidity, and there may be a limitation in the use. In addition, the thermal stability of EVOH deteriorates and the molded product is deteriorated. Not preferred.

The MFR of EVOH used in the present invention is:
It is preferably 0.1 to 50 g / 10 min, and more preferably 5 to 40 g / 10 min. These EVO
H can be used alone or in combination of two or more.

In the present invention, it is also a preferable embodiment that the polyamide resin is contained in the EVOH in a range of 1 to 40% by weight based on the EVOH in view of its mechanical properties and moldability. Specific examples of polyamide resins that can be used here include polycaproamide (nylon 6), polyundecaneamide (nylon 11), polydodecaneamide (nylon 12), polycaproamide / polyhexamethylene adipamide copolymer ( Nylon 6/66), polyhexamethylene sebacamide (nylon 610), polyhexamethylene dodecamide (nylon 612), and mixtures or copolymers thereof. Particularly preferred are nylon 6 and copolymers thereof.

Further, other resins may be contained as long as the object of the present invention is not impaired. At this time, the phase relationship and the like are as follows: (a) polyolefin resin and (b) EVO
It is sufficient that H satisfies the requirements of the present invention.

In the injection-molded article of the present invention, the polyolefin resin component forms a continuous phase and the EVOH component contains
It is a molded article having a phase structure (laminar structure) that forms a dispersed phase in the form of a band (layer) that is dimensionally overlapped, in part or in whole. There is no particular limitation on the shape of the molded body. Also,
The phase structure may appear multiple times at various places in the compact. This phase structure is observed and confirmed using a scanning and transmission electron microscope.

In the resin composition constituting the injection-molded article of the present invention, (a) a polyolefin resin and (b) EVO
H has a relationship of 55 to 95% by volume and 45 to 5% by volume, respectively. Preferably, they are 60 to 90% by volume and 40 to 10% by volume, respectively, and more preferably 65 to 85% by volume and 35 to 15% by volume, respectively. (A) When the polyolefin resin exceeds 95% by volume, it becomes difficult to make the EVOH band-shaped dispersed phase a sufficient length and amount,
The object of the present invention cannot be achieved. (A)
When the content of the polyolefin resin is less than 55% by volume, E
It becomes difficult for VOH to form a band-like dispersed phase.

In the injection molded article of the present invention, (a) the polyolefin resin is a continuous phase (matrix phase) and (b)
In order to form a dispersed phase (laminar structure, FIG. 1) as a plurality of thin two-dimensionally overlapped bands (layers) of EVOH, for example, the melt viscosity ratio of polyolefin resin / EVOH, compatibility (type of compatibilizer) , Addition amount), the resin temperature during injection molding, and the mold temperature can be achieved by appropriately controlling, for example, as shown in Examples.

L / T of EVOH that forms band-like dispersed phase
(Length / thickness) is preferably 30 or more. More preferably, L / T is 100 or more, particularly preferably L / T.
T is 150 or more. When L / T is 30 or less,
A structure that achieves the desired barrier properties cannot be obtained. The upper limit of L / T is not particularly limited, but is practically 1 × 10 ⁶ or less.

The injection molded article of the present invention can contain (c) an inorganic filler. The type of the filler is not particularly limited, but a fibrous, plate-like, powdery, granular filler, or the like can be used. Specifically, for example, glass fiber, polyacrylonitrile-based or pitch-based carbon fiber, stainless fiber, metal fiber such as aluminum fiber or brass fiber, organic fiber such as aromatic polyamide fiber, gypsum fiber, ceramic fiber, asbestos fiber, Fibrous such as zirconia fiber, alumina fiber, silica fiber, titanium oxide fiber, silicon carbide fiber, rock wool, potassium titanate whisker, barium titanate whisker, aluminum borate whisker, silicon nitride whisker, whisker-like filler, mica, talc , Kaolin,
Examples of the filler include powdery, granular, and plate-like fillers such as silica, calcium carbonate, glass beads, glass flakes, glass microballoons, clay, molybdenum disulfide, walasteinite, titanium oxide, zinc oxide, calcium polyphosphate, and graphite. Among the above fillers, glass fibers and PAN-based carbon fibers are preferably used when conductivity is required. The type of the glass fiber is not particularly limited as long as it is generally used for reinforcing a resin. For example, a long fiber type or a short fiber type chopped strand, a milled fiber or the like can be used. The above fillers can be used in combination of two or more kinds.
The surface of the filler used in the present invention is a known coupling agent (for example, a silane coupling agent,
Glass fiber can be coated with thermoplastic resin such as ethylene / vinyl acetate copolymer, thermosetting resin such as epoxy resin, or bundled. It may be.

The content of the inorganic filler is preferably 0.5 to 200 parts by weight based on 100 parts by weight of the total of (a) the polyolefin resin and (b) EVOH. More preferably, it is 5 to 200 parts by weight, particularly preferably 10 to 150 parts by weight.

In the injection molded article of the present invention, a conductive filler and / or a conductive polymer can be used to impart conductivity, and the material is not particularly limited. As the filler, there is no particular limitation as long as it is a conductive filler that is usually used for making the resin conductive.
Specific examples thereof include metal powder, metal flakes, metal ribbons, metal fibers, metal oxides, inorganic fillers coated with a conductive substance, carbon powder, graphite, carbon fibers, carbon flakes, flaky carbon, and the like. .

Specific examples of the metal species of the metal powder, metal flake, and metal ribbon include silver, nickel, copper, zinc, aluminum, stainless steel, iron, brass, chromium, and tin.

Specific examples of the metal species of the metal fiber include iron,
Examples thereof include copper, stainless steel, aluminum, and brass.

The metal powder, metal flake, metal ribbon and metal fiber may be subjected to a surface treatment with a surface treating agent such as a titanate, aluminum or silane.

Specific examples of the metal oxide include SnO ₂ (antimony doped), In ₂ O ₃ (antimony doped), Z
Examples thereof include nO (aluminum dope), which may be surface-treated with a surface treatment agent such as a titanate-based, aluminum-based, or silane-based coupling agent.

The inorganic filler coated with the conductive substance
Aluminum, nickel, etc.
, Silver, carbon, SnO_Two(Antimony dope), I
n_TwoO _Three(Antimony dope) and the like. In addition,
Mica, glass bee
Size, glass fiber, carbon fiber, potassium titanate whisker
ー, barium sulfate, zinc oxide, titanium oxide, aluminum borate
Minium whisker, zinc oxide whisker, titanium oxide
Acid whisker, silicon carbide whisker, etc.
You. As a coating method, a vacuum deposition method, a sputtering method,
Examples include an electroless plating method and a baking method. Again
These are titanate, aluminum and silane couplings
Surface treatment with a surface treatment agent such as an agent.

The carbon powder is classified into acetylene black, gas black, oil black, naphthalene black, thermal black, furnace black, lamp black, channel black, roll black, disk black and the like according to its raw material and production method. The raw material and the production method of the carbon powder that can be used in the present invention are not particularly limited, but acetylene black and furnace black are particularly preferably used. Various carbon powders having different properties such as particle diameter, surface area, DBP oil absorption, and ash content are produced. The carbon powder that can be used in the present invention is not particularly limited in these properties, but from the viewpoint of strength and electrical conductivity, the average particle size is 500 nm or less, particularly 5 to 100 nm,
Further, the thickness is preferably 10 to 70 nm. The specific surface area (BE
(T method) is preferably at least 10 m2 / g, more preferably at least 30 m2 / g. The DBP lubrication amount is preferably 50 ml / 100 g or more, particularly preferably 100 ml / 100 g or more. The ash content is preferably 0.5% by weight or less, particularly preferably 0.3% by weight or less.

The carbon powder may be subjected to a surface treatment with a surface treating agent such as a titanate, aluminum, or silane. It is also possible to use those granulated for improving the workability of the melt-kneading.

A molded article obtained by processing the injection-molded article composition of the present invention is often required to have a smooth surface. From such a viewpoint, the conductive filler used in the present invention is:
Like the inorganic filler (c) used in the present invention, the length / diameter ratio in the powdery, granular, plate-like, scale-like, or resin composition is more than that of the fibrous filler having a high aspect ratio.
It is preferably any one of fibrous forms of 0 or less.

Specific examples of the conductive polymer include polyaniline, polypyrrole, polyacetylene, poly (paraphenylene), polythiophene, and polyphenylenevinylene.

The above-mentioned conductive filler and / or conductive polymer may be used in combination of two or more kinds. Among these conductive fillers and conductive polymers, carbon black is particularly preferably used in terms of strength and economy.

The conductive filler used in the present invention and / or
Alternatively, since the content of the conductive polymer varies depending on the type of the conductive filler and / or the conductive polymer used, it cannot be unconditionally specified. However, from the viewpoint of the balance between conductivity, fluidity, mechanical strength, and the like, ( The range of 1 to 250 parts by weight, preferably 3 to 100 parts by weight, is preferably selected with respect to 100 parts by weight of the total of components a) and (b) and component (c). Further, more preferably, the range of 3 to 100 parts by weight is preferably selected for imparting a conductive function to the total of 100 parts by weight of the components (a) and (b).

When conductivity is imparted, its volume resistivity is 10 ¹⁰ Ω · c in order to obtain sufficient antistatic performance.
m or less. However, the blending of the above-mentioned conductive filler and conductive polymer generally tends to cause deterioration in strength and fluidity. Therefore, if a target conductivity level can be obtained, it is desirable that the amount of the conductive filler and conductive polymer is as small as possible. The target conductivity level depends on the application, but usually the volume resistivity is 100Ω
· It is more than ¹⁰ cm and not more than 10 ¹⁰ Ω · cm.

In the composition of the present invention, other components such as antioxidants and heat stabilizers (hindered phenols, hydroquinones, phosphites and substituted products thereof) within a range not to impair the effects of the present invention. ), Weathering agents (resorcinol, salicylate, benzotriazole, benzophenone, hindered amine, etc.), mold release agents and lubricants (montanic acid and its metal salts, esters, half esters, stearyl alcohol, stearamide, various bisamides) , Bisurea, polyethylene wax, etc.), pigments (cadmium sulfide, phthalocyanine, carbon black, etc.), dyes (nigrosine, etc.), crystal nucleating agents (talc, silica, kaolin, clay, etc.), plasticizers (octyl p-oxybenzoate) , N-butylbenzenesulfonamide, etc.) Antistatic agents (alkyl sulfate type anionic antistatic agents, quaternary ammonium salt type antistatic agents, nonionic antistatic agents such as polyoxyethylene sorbitan monostearate, betaine amphoteric antistatic agents, etc.), difficult Flame retardants (for example, hydroxides such as red phosphorus, melamine cyanurate, magnesium hydroxide, aluminum hydroxide, etc., ammonium polyphosphate, brominated polystyrene, brominated polyphenylene ether, brominated polycarbonate, brominated epoxy resin and brominated epoxy resins thereof) Combination of flame retardant and antimony trioxide),
Other polymers can be added.

The injection-molded article of the present invention has various embodiments. Various known injection molding methods can be used as the molding method. However, injection molding, injection compression molding, and two-color injection molding can be used. It is preferable to adopt one method selected from the methods, since the object of the invention can be easily achieved. The molding temperature is usually selected from a temperature range 5 to 50 ° C. higher than the melting point of EVOH, and is generally a single layer.
A multilayer structure may be used by a method such as a color injection molding method.

Here, the multilayer structure means a structure having the phase structure of the present invention in at least one layer. The arrangement of each layer is not particularly limited, and all the layers may be formed of the resin composition according to the present invention, or another layer of a thermoplastic resin may be used.

The thermoplastic resin used as another layer includes saturated polyester, polysulfone, polyethylene tetrafluoride, polyetherimide, polyamideimide, polyamide, polyketone copolymer, polyphenylene ether, polyimide, polyethersulfone, and polyether. Ketone, polythioetherketone, polyetheretherketone, thermoplastic polyurethane, polyolefin, A
Examples include BS, polyamide elastomer, polyester elastomer, and the like, and a mixture thereof or various additives may be used.

The injection-molded article of the present invention can be preferably used as a container for transporting and / or storing a chemical solution or gas or an accessory thereof, utilizing its excellent gas barrier properties, durability and moldability. Examples of the chemical solution and gas include Freon-11, Freon-12, and Freon-2.
1, Freon-22, Freon-113, Freon-114,
Freon-115, Freon-134a, Freon-32, Freon-123, Freon-124, Freon-125, Freon-143a, Freon-141b, Freon-142b,
Freon-225, Freon-C318, R-502, 1,
1,1-trichloroethane, methyl chloride, methylene chloride, ethyl chloride, methyl chloroform, propane, isobutane, n-butane, dimethyl ether, castor oil-based brake fluid, glycol ether-based brake fluid, borate-based brake fluid, for extreme cold regions Brake fluid, silicone oil-based brake fluid, mineral oil-based brake fluid, power steering oil, window washer fluid, gasoline, methanol, ethanol, isoptanol, butanol,
Nitrogen, oxygen, hydrogen, carbon dioxide, methane, propane, natural gas, argon, helium, xenon, pharmaceutical agents and other gases and / or liquids or vaporized gases, etc., have excellent permeation resistance. And / or liquid permeation-resistant films, airbags, shampoos, rinses, liquid soaps, detergents and other chemical bottles, chemical liquid storage tanks, gas storage tanks, cooling liquid tanks, oil transfer tanks Tanks, disinfectant tanks, blood transfusion pump tanks, fuel tanks, canisters, washer liquid tanks, oil reservoir tanks, and other automotive parts, medical equipment parts, and general living equipment parts tanks, bottle-shaped molded articles, or their tanks , Valves and fittings such as cut-off valves and ORVR valves attached to bottles, Up of gauge, parts such as the case class,
Fuel filler underpipe, ORVR hose,
Connection parts (connectors, etc.) for various fuel tubes such as reserve hoses and vent hoses, connection parts for oil tubes, connection parts for brake hoses, nozzles for window washer fluid, connection parts for cooler hoses for cooling water, refrigerant, etc., and air conditioners Refrigerant tube connection parts, floor heating pipe connection parts, fire extinguishers and fire extinguisher hoses, medical cooling equipment tube connection parts and valves, other chemical and gas transport tube applications, chemical storage containers Such as applications that require chemical and gas permeation resistance, automotive parts, internal combustion engine applications, mechanical parts such as power tool housings, electrical and electronic parts, medical care, food, household and office supplies, and building materials related parts. And various uses such as furniture parts.

[0050]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to Examples, but the gist of the present invention is not limited to the following Examples. (1) Alcohol gasoline permeability A square plate (80 × 80 mm) test piece having a thickness of 1 mm was prepared by injection molding (IS100FA manufactured by Toshiba Machine Co., cylinder temperature: 210 ° C., mold temperature: 60 ° C.). This test piece was cut out, and a gasoline permeability measuring device (manufactured by Yanaco Kagaku Kogyo Co., Ltd., G
Using TR-3XAT), the permeability coefficient at 40 ° C. of an alcohol gasoline mixture obtained by mixing a model gasoline (toluene // isooctane = 50 // 50 vol%) and ethanol at a weight ratio of 90 to 10 was measured. (2) Liquid Absorbency of Alcohol Gasoline A mass-shaped molded product (FIG. 2) prepared by injection molding (Toshiba Machine Co., IS100FA, cylinder temperature 230 ° C., mold temperature 60 ° C.) was mixed with model gasoline in an autoclave. After being immersed in alcohol gasoline mixed with ethanol at a weight ratio of 90 to 10, it was placed in an explosion-proof oven at 40 ° C. for 24 hours, and the amount of weight absorbed was measured. (3) Heat weldability ASTM1 by injection molding (Toshiba Machine Co., IS100FA, cylinder temperature 230 ° C, mold temperature 60 ° C)
A test piece having a 1/2 shape in the length direction of the tensile test piece was prepared (FIG. 3). The cross section of this test piece was melted for 30 seconds on a hot plate heated to 300 ° C. covered with a Teflon (registered trademark) sheet for 30 seconds, and then HDPE prepared similarly.
(“HIZEX” 8200B, manufactured by Mitsui Chemicals, Inc.) A test piece and a molten cross-section were bonded to prepare a heat-welded test piece. The tensile properties of the obtained heat-welded test pieces were measured in accordance with ASTM D638. (4) Material strength Measured according to the following standard method. Tensile strength: ASTM D638 Izod impact strength: ASTM D256 (5) Observation of phase separation structure An electron microscope (TEM, SEM) was used to observe a portion of the ASTM No. 1 specimen 1 mm from the surface in the thickness direction. (6) Melt viscosity ratio Using a plunger-type capillary rheometer (manufactured by Toyo Seiki Seisaku-sho, Co., Ltd., Capillograph type 1C), 2
The melt viscosity (Pa · s) at a shear rate of 1000 sec ⁻¹ at 30 ° C. was measured and determined by the following equation. (Melting viscosity ratio) = (Melting viscosity of EVOH) / (Melting viscosity of polyolefin resin) Next, materials used in Examples will be described. Unless otherwise specified, each resin is synthesized by a conventional method. <Polyolefin resin: PO> (A-1): MFR 0.04 g / 10 min, density 0.95
6. High density polyethylene. (A-2): High-density polyethylene having a MFR of 6 g / 10 min and a density of 0.956. (A-3): an ethylene / 1-hexene copolymer having a MFR of 4 g / 10 min and a density of 0.920. <Compatibilizer component> (EMAA): ethylene-methacrylic acid copolymer (Nucrel AN4214 manufactured by DuPont-Mitsui Polychemicals)
C). <EVOH> (B-1): ethylene content 32 mol%, melting point 186
EVOH with a MFR of 3.2 g / 10 min (210 ° C.). (B-2): ethylene content 44 mol%, melting point 167
EVOH having a MFR of 12 g / 10 min (210 ° C.). (B-3): EVOH // Nylon 6 of B-1 (Amilan CM1017 manufactured by Toray Industries, Inc.) = 90 // 10 parts by weight are mixed and melt-kneaded at a cylinder temperature of 240 ° C. using a twin-screw extruder. Composition. <Inorganic filler> (GF): glass fiber (fiber diameter 10 μm, 3 mm chopped strand, manufactured by NEC Corporation).

Examples 1 to 6 and Comparative Examples 1 to 3 As shown in Table 1, EVOH, a polyolefin resin and a polyolefin resin having an action as a compatibilizer were mixed with a main feeder of a TEX30 type twin screw extruder manufactured by Nippon Steel Works, Ltd. In the case of supplying the inorganic filler, the melt-kneading was performed at a kneading temperature of 230 ° C. and a screw rotation speed of 200 rpm by a method using a side feeder in the middle of the cylinder. After drying the obtained pellet, a test piece was prepared by injection molding (IS100FA manufactured by Toshiba Machine Co., cylinder temperature 230 ° C, mold temperature 60 ° C). Table 1 shows the results of measurement of the barrier properties, thermal welding properties, material strength, and the like of each sample.

[0052]

[Table 1]

The injection-molded article of the present invention in which a specific phase-separated structure is defined from Examples 1 to 6 and Comparative Examples 1 to 3 has excellent barrier properties and excellent weldability, and further has a molded article (product). The degree of freedom of the shape is extremely high, and a molded product having a shape that cannot be obtained by extrusion molding has a high barrier property and a high practical value.

[0054]

The injection-molded article of the present invention has good barrier properties and moldability, and can be developed for various uses.
For example, it is suitable for electrical / electronic related equipment, precision machine related equipment, office equipment, automobile / vehicle related parts, building materials, packaging materials, furniture, daily necessities and the like.

[Brief description of the drawings]

FIG. 1 A polyolefin resin component forms a continuous phase,
Many thin two-dimensionally overlapped bands (layers) of EVOH components
FIG. 3 is a model diagram of a phase structure forming a dispersed phase as a shape.

FIG. 2 is a perspective view of a mass-shaped molded product.

FIG. 3 is a side perspective view of a mass-shaped molded product.

FIG. 4 is an explanatory view of a test piece for evaluating thermal welding properties.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // (C08L 101/00 C08L 29:04 S 29:04 23:26) 23:26) B29K 23:00 B29K 23:00 55:00 55:00 105: 16 105: 16 B29L 22:00 B29L 22:00 B65D 1/00 A F term (reference) 3E033 BA13 BA14 BB01 CA16 CA20 FA02 4F071 AA14 AA15 AA15X AA20 AA21 AA22 AA29X AA31 AA76 AE17 AF07 AF53 AH04 AH05 AH07 AH12 BA01 BB05 BC04 BC17 4F206 AA03 AA19E AG07 JA07 JF01 JF21 4J002 BB001 BB021 BB031 BB111 BB161 BB222 BC021 BE032 BF001 BG021 FD016 GG01 00

Claims (5)

[Claims] 1. A method according to claim 1, wherein (a) the polyolefin resin and (b) the ethylene-vinyl alcohol copolymer are 55 to 95, respectively.
% By volume and 45 to 5% by volume in a resin phase separation structure observed by an electron microscope, wherein (a) a continuous phase composed of a polyolefin resin and (b) ethylene-vinyl alcohol An injection-molded article characterized by forming a phase structure composed of a band-shaped dispersed phase composed of a polymer. 2. The mixing ratio of (a) the polyolefin resin and (b) the ethylene-vinyl alcohol copolymer is 6
The injection-molded article according to claim 1, wherein the amount is 0 to 75% by volume and 40 to 25% by volume. 3. The injection-molded article according to claim 1, wherein (a) the polyolefin resin is polyethylene. 4. An inorganic filler of 0.5 to 20 parts by weight based on a total of 100 parts by weight of the polyolefin resin of the component (a) and the ethylene-vinyl alcohol copolymer of the component (b).
The injection molded article according to any one of claims 1 to 3, wherein the injection molded article contains 0 parts by weight. 5. The injection-molded article according to claim 1, which is a container for transporting and / or storing a chemical solution or gas or an accessory thereof.