JP2022007471A - Resin composition, molding, multilayer structure, packaging material, vertical bag filling sealed bag, inner container for bag-in-box, delamination container, multilayer pipe and blow molding container - Google Patents

Abstract

To provide a resin composition which gives a molding that suppresses occurrence of spitting during melt-molding, has sufficient heat and light resistances and is less likely to be formed into micro-plastic after disposal.SOLUTION: A resin composition contains an ethylene-vinyl alcohol copolymer EVOH (A), aluminum ions (B) and a thermoplastic elastomer (F), in which at least a part of the EVOH (A) has at least one of a carboxylic acid unit (I) and a lactone ring unit (II) positioned on the polymer terminal, the total content (i+ii) of the carboxylic acid unit (I) and the lactone ring unit (II) per 1 g of the EVOH (A) is 14 μmol/g or more and 78 μmol/g or less, and a content (b) of the aluminum ions (B) per 1 g of the EVOH (A) is 0.002 μmol/g or more and 0.17 μmol/g or less.SELECTED DRAWING: Figure 5

Description

The present invention relates to a resin composition, a molded body, a multilayer structure, a packaging material, a vertical bag-filled seal bag, an inner container for a bag-in-box, a laminated peeling container, a multilayer tube and a blow molded container.

Generally, an ethylene-vinyl alcohol copolymer (hereinafter, also referred to as “EVOH”) is excellent in transparency, gas barrier property, fragrance retention property, solvent resistance, oil resistance and the like. Taking advantage of these characteristics, EVOH is used in films, sheets, containers and the like as packaging materials for foods, pharmaceuticals, industrial chemicals, pesticides and the like. In addition, EVOH is also used in fuel tanks for automobiles and other vehicles, tube materials for tires, agricultural films, geomembranes, cushioning materials for shoes, etc. by taking advantage of its barrier properties, heat retention properties, stain resistance, etc. ing.

EVOH has lower thermal stability than other resins, and may cause bumps during heat treatment and molding. Further, EVOH may have a reduced mechanical strength when exposed to light, heat or the like due to outdoor use. Regarding the thermal stability of EVOH, Patent Document 1 includes ethylene unit (III), vinyl alcohol unit (IV) and vinyl ester unit (V), and the ratio of ethylene unit (III) to the total of the above units (III + IV + V). Is 20 to 60 mol%, and the ratio of the total (I + II) of the carboxylic acid group unit (I) and the lactone ring unit (II) at the polymer terminal of the copolymer to the total (III + IV + V) of the above units is 0.12 mol% or less. EVOH is described. According to Patent Document 1, EVOH having a small number of terminal carboxylic acid units and lactone ring units is less likely to cause lumps during heat treatment and molding, and improves long-running properties during melt molding.

International Publication No. 2004/092234

However, the EVOH of Patent Document 1 has a ratio of the total (I + II) of the carboxylic acid unit (I) and the lactone ring unit (II) of 0.12 mol% or less, and EVOH having a high total ratio has heat. It has not been possible to improve the stability, that is, to suppress the lumps generated during the heat treatment and the molding process. Further, the EVOH of Patent Document 1 does not consider heat resistance and light resistance in consideration of long-term use outdoors. Furthermore, in recent years, it has become a problem that discarded plastic products flow out into the ocean and become microplastics that pollute the ocean. Therefore, there is a demand for the development of a resin that is difficult to make into microplastic. In particular, as shown in Table 11 (Reference Comparative Examples 18 to 20) of Examples described later, the total of the carboxylic acid unit (I) and the lactone ring unit (II) such as EVOH of Patent Document 1 above. The inventors have found that those having a low ratio of (I + II) are likely to be microplasticized.

On the other hand, the properties of EVOH such as thermal stability and heat resistance and light resistance are influenced by the structure of EVOH itself such as ethylene content. Therefore, it is possible to improve the thermal stability, heat resistance and light resistance, etc. to some extent by adjusting the ethylene content and the like. However, since EVOH having a suitable ethylene content or the like according to the intended use of the molded product is usually used, each property such as thermal stability and heat resistance and light resistance should be improved without changing the EVOH itself. Is desired.

In addition, EVOH has a large number of hydroxyl groups in the molecule and has high crystallinity and crystallization rate, so that it has low flexibility. Therefore, when EVOH is molded into various packaging materials, containers, etc., pinholes and cracks may occur due to bending.

The present invention has been made based on the above circumstances, and an object thereof is a molded product that suppresses the generation of lumps during melt molding, has sufficient heat and light resistance, and is difficult to be microplasticized after disposal. The above-mentioned characteristics are sufficiently improved as compared with the resin composition using the same EVOH, and the obtained molded product or the like has excellent bending resistance, and the resin composition thereof. It is an object of the present invention to provide a molded body, a multilayer structure, a packaging material, a vertical bag-filled seal bag, an inner container for a bag-in-box, a laminated peeling container, a multilayer tube and a blow molded container using a resin composition.

According to the present invention, the above object is
[1] A resin composition containing an ethylene-vinyl alcohol copolymer (A), an aluminum ion (B) and a thermoplastic elastomer (F), at least a part of the ethylene-vinyl alcohol copolymer (A). Has at least one of the carboxylic acid unit (I) and the lactone ring unit (II) located at the end of the polymer, and the carboxylic acid unit (I) and the lactone ring per 1 g of the ethylene-vinyl alcohol copolymer (A). The total content (i + ii) of the unit (II) is 14 μmol / g or more and 78 μmol / g or less, and the content (b) of the aluminum ion (B) per 1 g of the ethylene-vinyl alcohol copolymer (A) is 0. 002 μmol / g or more and 0.17 μmol / g or less, and the mass ratio (F / A) of the thermoplastic elastomer (F) to the ethylene-vinyl alcohol copolymer (A) is 5/95 or more and 35/65 or less. Resin composition;
[2] The ratio ((i + ii) / b) of the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) to the content (b) of the aluminum ion (B) is 180 or more and 20. The resin composition of [1], which is 000 or less;
[3] The resin composition of [1] or [2], wherein the aluminum ion (B) is derived from a fatty acid aluminum salt having 5 or less carbon atoms;
[4] Further contains at least one compound (C) selected from the group consisting of cinnamon acids and conjugated polyene compounds having a molecular weight of 1,000 or less, and the compound (C) contained in the ethylene-vinyl alcohol copolymer (A). The resin composition according to any one of [1] to [3], wherein the amount (c) is 1 ppm or more and 1,000 ppm or less.
[5] When the ratio (ii / (i + ii)) of the content (ii) of the lactone ring unit (II) to the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) is 40 mol% or more. A resin composition according to any one of [1] to [4];
[6] Any one of [1] to [5], wherein the thermoplastic elastomer (F) is at least one selected from the group consisting of a polyester-based thermoplastic elastomer, a polystyrene-based thermoplastic elastomer, and a polyolefin-based thermoplastic elastomer. Resin composition of;
[7] The thermoplastic elastomer (F) contains a modified thermoplastic elastomer (F2), and the modified thermoplastic elastomer (F2) is a modified thermoplastic elastomer modified with an unsaturated carboxylic acid or a derivative thereof. The resin composition according to any one of 1] to [6];
[8] The resin composition of [7], wherein the content ratio (F2 / F) of the modified thermoplastic elastomer (F2) with respect to the thermoplastic elastomer (F) is 5% by mass or more and 100% by mass or less.
[9] The resin composition according to any one of [1] to [8], wherein the thermoplastic elastomer (F) contains a polystyrene-based thermoplastic elastomer (F3) containing a halogen atom;
[10] A molded product molded from the resin composition according to any one of [1] to [9];
[11] A multilayer structure having a layer made of the resin composition according to any one of [1] to [9];
[12] A packaging material having the multilayer structure of [11];
[13] A vertical bag-filled seal bag having the multilayer structure of [11];
[14] An inner container for a bag-in-box having the multilayer structure of [11];
[15] A laminate peeling container provided with the multilayer structure of [11], wherein the multilayer structure is directly laminated on one surface of a layer made of the resin composition, and a polyolefin having no polar functional group is provided. Laminated stripping container with a layer as the main component;
[16] A multi-layer tube having the multi-layer structure of [11];
[17] A blow-molded container having the multilayer structure of [11];
Achieved by providing one of the above.

According to the present invention, it is a resin composition that suppresses the generation of lumps during melt molding, has sufficient heat resistance and light resistance, and can obtain a molded body that is difficult to be microplasticized after disposal, and uses the same EVOH. In comparison, each of the above characteristics is sufficiently improved, and a resin composition in which the obtained molded body or the like is excellent in bending resistance, and a molded body, a multilayer structure, a packaging material using this resin composition, etc. It is possible to provide a vertical bag-filled seal bag, an inner container for a bag-in-box, a laminated peeling container, a multi-layer tube, a blow-molded container, and the like.

Solvent: DMSO-d ₆ Measurement temperature: ¹ H-NMR spectrum of EVOH-A of Synthesis Example 1 measured under the condition of 25 ° C. Solvent: DMSO-d ₆ Measurement temperature: ¹ H-NMR spectrum of EVOH-A of Synthesis Example 1 measured under the condition of 80 ° C. ¹ H-NMR spectrum of EVOH-A of Synthesis Example 1 measured under the condition of solvent: D ₂ O + MeOD measurement temperature: 80 ° C. It is a back view which shows the vertical bag filling seal bag which concerns on one Embodiment of this invention. It is a schematic partial sectional view which shows the blow-molded container which is one Embodiment of the blow-molded container of this invention.

<Resin composition>
The resin composition of the present invention contains an ethylene-vinyl alcohol copolymer (A) (hereinafter, may be referred to as "EVOH (A)"), an aluminum ion (B), and a thermoplastic elastomer (F). .. At least a portion of EVOH (A) has at least one of a carboxylic acid unit (I) and a lactone ring unit (II) located at the end of the polymer. The total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) per 1 g of EVOH (A) is 14 μmol / g or more and 78 μmol / g or less. The content (b) of aluminum ions (B) per 1 g of EVOH (A) is 0.002 μmol / g or more and 0.17 μmol / g or less. The mass ratio (F / A) of the thermoplastic elastomer (F) to EVOH (A) is 5/95 or more and 35/65 or less.

The resin composition of the present invention is a resin composition that suppresses the generation of lumps during melt molding, has sufficient heat resistance and light resistance, and can obtain a molded product that is difficult to be microplasticized after disposal, and the same EVOH is used. Each of the above characteristics is sufficiently improved as compared with the above. Therefore, according to the resin composition of the present invention, the generation of lumps is further suppressed without changing the type of EVOH, and the heat resistance and light resistance and the resistance to microplasticization of the obtained molded product are enhanced. The reason for this effect is not clear, but the following is presumed. A stable structure is formed by the interaction of a predetermined amount of aluminum ion (B) with the carboxylic acid unit (I) and the lactone ring unit (II) located at the terminal of EVOH (A). As a result, gelation during melt molding is suppressed, and as a result, the generation of lumps is suppressed. Further, it is presumed that the obtained molded product also has excellent heat resistance and light resistance as a result of forming the above stable structure, and it is difficult to make it into microplastic after disposal.

Further, the resin composition of the present invention contains a predetermined amount of the thermoplastic elastomer (F), and the total content of the carboxylic acid unit (I) and the lactone ring unit (II) per 1 g of EVOH (A) ( i + ii) is 14 μmol / g or more and 78 μmol / g or less, and the content (b) of the aluminum ion (B) per 1 g of EVOH (A) is 0.002 μmol / g or more and 0.17 μmol / g or less. The obtained molded product or the like has sufficient heat and light resistance and microplasticization resistance, and has excellent bending resistance. Although the reason for this is not clear, in addition to the effect of the thermoplastic elastomer (F), the carboxylic acid unit (I) and the lactone ring unit (I) in which the above-mentioned predetermined amount of aluminum ion (B) is located at the end of EVOH (A) ( It is presumed that the stable structure formed by interacting with II) also contributes to bending resistance.

The resin composition of the present invention may further contain components other than EVOH (A), aluminum ion (B) and thermoplastic elastomer (F). Hereinafter, each component and the like of the resin composition of the present invention will be described in detail.

(EVOH (A))
EVOH (A) is a copolymer having an ethylene unit and a vinyl alcohol unit. EVOH (A) is usually obtained by a saponification reaction of an ethylene-vinyl ester copolymer. Therefore, EVOH (A) may further have the remaining vinyl ester units. That is, EVOH (A) is a copolymer having an ethylene unit and a vinyl alcohol unit, and further having or not having a vinyl ester unit as an arbitrary monomer unit. The ethylene-vinyl ester copolymer can be produced and saponified by a known method. Vinyl acetate is a typical vinyl ester, but other fatty acid vinyls such as vinyl formate, vinyl propionate, vinyl valerate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl pivalate and vinyl versatic acid. It may be an ester.

At least a portion of EVOH (A) has at least one of a carboxylic acid unit (I) and a lactone ring unit (II) located at the polymer terminal (main chain terminal). The carboxylic acid unit (I) is a structural unit located at the end of the polymer and refers to a structural unit having a carboxy group. The carboxylic acid unit (I) is also referred to as a terminal carboxylic acid unit. Some or all of the carboxy groups of the carboxylic acid unit (I) may be present in the salt or anion (-COO- ⁾ state. The lactone ring unit (II) is a structural unit located at the end of the polymer and refers to a structural unit having a lactone ring. The lactone ring unit (II) is also referred to as a terminal lactone ring unit. The number of ring members of the lactone ring is not particularly limited, and may be, for example, a 4- to 6-membered ring, preferably a 5-membered ring. The carboxylic acid unit (I) may be, for example, a structural unit represented by the following formula (1). The lactone ring unit (II) may be, for example, a structural unit represented by the following formula (2).

In formula (1), X is a hydrogen atom, a hydroxy group or an esterified hydroxy group. Y is a hydrogen atom or a metal atom.

Examples of the esterified hydroxy group represented by X include -OCO-CH ₃ , -OCO-C ₂ H ₅ , and the like.

Examples of the metal atom represented by Y include alkali metals such as sodium, alkaline earth metals such as magnesium and calcium, metals which are typical elements such as aluminum, and transition metals. Among them, typical elements are preferable, and alkali metals, alkaline earth metals and aluminum are preferable. When Y is aluminum, this aluminum is contained in the aluminum ion (B). When Y is a metal atom having a valence of 2 or more, two or more carboxylate anions (-COO- ⁾ may be bonded or coordinated to one Y.

The total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) per 1 g of EVOH (A), that is, the carboxylic acid unit (I) and the lactone ring unit (II) present in 1 g of EVOH (A). ) Is the lower limit of the total amount (amount of substance: number of moles) of 14 μmol / g, preferably 18 μmol / g, and more preferably 22 μmol / g. The lower limit of the total content of the carboxylic acid unit (I) and the lactone ring unit (II) with respect to the total content of the ethylene unit, vinyl alcohol unit and vinyl ester unit of EVOH (A) is preferably 0.10 mol%. 0.12 mol% is more preferable, and 0.14 mol% is further preferable. When the total content of the carboxylic acid unit (I) and the lactone ring unit (II) is at least the above lower limit, the interaction with the aluminum ion (B) is sufficiently generated, and the resistance to microplasticization is particularly improved.

On the other hand, the upper limit of the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) per 1 g of EVOH (A) is 78 μmol / g, preferably 70 μmol / g, and 60 μmol / g. More preferably, 50 μmol / g is further preferable, and 40 μmol / g is particularly preferable. The upper limit of the total content of the carboxylic acid unit (I) and the lactone ring unit (II) with respect to the total content of the ethylene unit, vinyl alcohol unit and vinyl ester unit of EVOH (A) is preferably 0.4 mol%. 0.3 mol% is more preferable, and 0.25 mol% is further preferable. If there are too many carboxylic acid units (I) and lactone ring units (II), the thermal stability will decrease. Specifically, the carboxylic acid group unit (I) and the lactone ring unit (II) can react with the hydroxy group of EVOH (A) at a high temperature to form a polymer having a high degree of polymerization and having a branch. Therefore, if the content of the carboxylic acid unit (I) and the lactone ring unit (II) is large, the melt moldability of EVOH (A) tends to be lowered. Therefore, when the total content of the carboxylic acid unit (I) and the lactone ring unit (II) is not more than the above upper limit, the generation of lumps during melt molding can be suppressed.

Ratio of the content (ii) of the lactone ring unit (II) to the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) of EVOH (A) (ii / (i + ii): lactone ring unit The lower limit of the ratio) may be, for example, 30 mol%, but 40 mol% is preferable, and 50 mol% is more preferable. When the lactone ring unit ratio (ii / (i + ii)) is equal to or higher than the above lower limit, heat resistance and microplasticization resistance tend to be further enhanced due to effective interaction with aluminum ion (B) and the like. be. On the other hand, the upper limit of the lactone ring unit ratio (ii / (i + ii)) may be, for example, 90 mol%, 80 mol% or 70 mol%.

The total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) per 1 g of EVOH (A) is adjusted by, for example, polymerization conditions such as the type of polymerization initiator, drying conditions such as a dry atmosphere, and the like. To. In EVOH (A) having no branched structure, the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) tends to be relatively small when the degree of polymerization is high. In many cases, it does not follow the trend. For example, as described in Patent Document 1, the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) is obtained by contacting the ethylene-vinyl ester copolymer or EVOH with a reducing agent. Can be reduced. On the contrary, the total content of the carboxylic acid unit (I) and the lactone ring unit (II) is contained by contacting the ethylene-vinyl ester copolymer or EVOH with an oxidizing agent or drying in an atmosphere that is easily oxidized. It is also possible to increase the amount (i + ii). Further, the ratio of the content (ii) of the lactone ring unit (II) to the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) (ii / (i + ii): lactone ring unit ratio) is , Can be adjusted according to the saponification conditions. For example, when saponification is performed under the condition that saponification is promoted, the lactone ring unit ratio (ii / (i + ii)) tends to increase.

The total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) located at the polymer terminal of EVOH (A) and the lactone ring unit ratio (ii / (i + ii)) are ¹ H-NMR measurement. Is sought after. The inventors have found that the above measurement results differ depending on the type of solvent used in the measurement. Therefore, the above measurement shall be performed using a mixed solvent of water / methanol (mass ratio 4/6, but if the sample does not dissolve, the mass ratio is appropriately changed). Specifically, the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) and the lactone ring unit ratio (ii / (i + ii)) are measured by the methods described in Examples described later. Value.

The lower limit of the ethylene unit content of EVOH (A) is preferably 10 mol%, more preferably 15 mol%, still more preferably 20 mol%, and even more preferably 25 mol%. On the other hand, the upper limit of the ethylene unit content of EVOH (A) is preferably 60 mol%, more preferably 55 mol%, and even more preferably 50 mol% or 45 mol%. By setting the content of ethylene units to the above lower limit or higher, thermal stability, resistance to microplasticization, and the like tend to be improved. Further, by setting the content of ethylene units to the above lower limit or less, the oxygen barrier property and the like tend to be improved.

The lower limit of the saponification degree of EVOH (A) is preferably 90 mol%, more preferably 95 mol%, further preferably 99 mol%, and particularly preferably 99.6 mol%. By setting the saponification degree of EVOH (A) to the above lower limit or higher, the melt moldability, the gas barrier property of the obtained molded product and the like, the heat resistance and light resistance, the moisture resistance and the like tend to be improved. Further, the saponification degree may be 100 mol% or less, 99.97 mol% or less, or 99.94 mol% or less.

EVOH (A) contains carboxylic acid units (I), lactone ring units (II), and units derived from ethylene, vinyl esters and other monomers other than the saponified product, as long as the effects of the present invention are not impaired. You may have. The content of EVOH (A) in all structural units of units derived from other monomers (units other than carboxylic acid unit (I), lactone ring unit (II), ethylene unit, vinyl ester unit and vinyl alcohol unit) is 30 mol% or less is preferable, 20 mol% or less is more preferable, 10 mol% or less is further preferable, 5 mol% or less is further preferable, and 1 mol% or less is particularly preferable. When EVOH (A) has a unit derived from the other monomer, the content thereof may be 0.05 mol% or more or 0.1 mol% or more.

Other monomers include unsaturated acids such as acrylic acid, methacrylic acid, crotonic acid and itaconic acid or anhydrides, salts thereof, or mono or dialkyl esters; nitriles such as acrylonitrile and methacrylic acid; acrylamide and methacrylic. Amid such as amide; olefin sulfonic acid such as vinyl sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid or a salt thereof; vinyl trimethoxysilane, vinyl triethoxysilane, vinyl tri (β-methoxy-ethoxy) silane, γ-methacrylic acid. Vinyl silane compounds such as propylmethoxysilane; alkyl vinyl ethers, vinyl ketones, N-vinylpyrrolidone, vinyl chloride, vinylidene chloride and the like can be mentioned.

The units derived from other monomers are represented by the structural unit (X) represented by the following formula (I), the structural unit (Y) represented by the following formula (II), and the following formula (III). It may be at least one of the structural units (Z) to be formed.

In the above formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ are independently hydrogen atoms and 1 to 10 carbon atoms, respectively. Represents an aliphatic hydrocarbon group, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or a hydroxyl group. A pair of R ¹ , R ² and R ³ , R ⁴ and R ⁵ , and R ⁶ and R ⁷ may be bonded (provided that a pair of R ¹ , R ² and R ³ are all hydrogen atoms. And when ^R4 and ^R5 , or ^R6 and ^R7 are both hydrogen atoms). In addition, some or all of the hydrogen atoms of the aliphatic hydrocarbon group having 1 to 10 carbon atoms, the alicyclic hydrocarbon group having 3 to 10 carbon atoms, and the aromatic hydrocarbon group having 6 to 10 carbon atoms are present. It may be substituted with a hydroxyl group, an alkoxy group, a carboxyl group or a halogen atom. In the above formula, R ¹² and R ¹³ independently represent a hydrogen atom, a formyl group, or an alkanoyl group having 2 to 10 carbon atoms.

When EVOH (A) has a structural unit (X), (Y) or (Z), the flexibility and processing characteristics of the resin composition are improved, and the stretchability and thermoformability in the obtained molded body or multilayer structure are improved. Etc. tend to be good.

In the structural unit (X), (Y) or (Z), examples of the aliphatic hydrocarbon group having 1 to 10 carbon atoms include an alkyl group and an alkenyl group. Examples of the alicyclic hydrocarbon group having 3 to 10 carbon atoms include a cycloalkyl group and a cycloalkenyl group. Examples of the aromatic hydrocarbon group having 6 to 10 carbon atoms include a phenyl group and the like.

In the structural unit (X), R ¹ , R ² and R ³ are preferably hydrogen atoms, methyl groups, ethyl groups, hydroxyl groups, hydroxymethyl groups and hydroxyethyl groups, respectively, and among them, the obtained multilayer structure and the like. From the viewpoint of further improving the stretchability and the thermoformability in the above, hydrogen atom, methyl group, hydroxyl group and hydroxymethyl group are more preferable independently.

The method of containing the structural unit (X) in the EVOH (A) is not particularly limited, and for example, in the polymerization of ethylene and vinyl ester, a method of copolymerizing a monomer induced by the structural unit (X) may be used. Can be mentioned. Examples of the monomer derived to the structural unit (X) include alkenes such as propylene, butylene, pentene, and hexene; 3-hydroxy-1-propene, 3-acyloxy-1-propene, and 3-acyloxy-1-butene. , 3-Hydroxy-1-butene, 4-hydroxy-1-butene, 4-acidoxy-1-butene, 3,4-diasiloxy-1-butene, 3-acidoxy-4-hydroxy-1-butene, 4-acidoxy -3-Hydroxy-1-butene, 3-Asiloxy-4-methyl-1-butene, 4-Asiloxy-2-methyl-1-butene, 4-Achilloxy-3-methyl-1-butene, 3,4-diasiloxy -2-Methyl-1-butene, 4-hydroxy-1-pentene, 5-hydroxy-1-pentene, 4,5-dihydroxy-1-pentene, 4-acidoxy-1-pentene, 5-acyloxy-1-pentene , 4,5-diasiloxy-1-pentene, 4-hydroxy-3-methyl-1-pentene, 5-hydroxy-3-methyl-1-pentene, 4,5-dihydroxy-3-methyl-1-pentene, 5 , 6-Dihydroxy-1-hexene, 4-hydroxy-1-hexene, 5-hydroxy-1-hexene, 6-hydroxy-1-hexene, 4-acyloxy-1-hexene, 5-acyloxy-1-hexene, 6 Examples thereof include alkenes having a hydroxyl group or an ester group such as asyloxy-1-hexene and 5,6-diasiloxy-1-hexene. Above all, from the viewpoint of copolymerization reactivity, processability of the obtained molded body and multilayer structure, and gas barrier property, propylene, 3-acyloxy-1-propene, 3-acyloxy-1-butene, 4-acyloxy-1 -Butene and 3,4-diasiloxy-1-butene are preferred. As "acyloxy", acetoxy is preferable, and specifically, 3-acetoxy-1-propene, 3-acetoxy-1-butene, 4-acetoxy-1-butene and 3,4-diacetoxy-1-butene are preferable. In the case of an ester-bearing alkene, it is induced to the structural unit (X) during the saponification reaction.

In the structural unit (Y), it is preferable that both R ⁴ and R ⁵ are hydrogen atoms. In particular, it is more preferable that both R ⁴ and R ⁵ are hydrogen atoms, one of R ⁶ and R ⁷ is an aliphatic hydrocarbon group having 1 to 10 carbon atoms, and the other is a hydrogen atom. As the aliphatic hydrocarbon group, an alkyl group and an alkenyl group are preferable. From the viewpoint of particularly placing importance on the gas barrier property in the obtained molded body and the multilayer structure, it is more preferable that one of R ⁶ and R ⁷ is a methyl group or an ethyl group and the other is a hydrogen atom. Further, it is more preferable that one of R ⁶ and R ⁷ is a substituent represented by (CH ₂ ) _h OH (where h is an integer of 1 to 8) and the other is a hydrogen atom. In addition, h is preferably an integer of 1 to 4, more preferably 1 or 2, and even more preferably 1.

The method of containing the structural unit (Y) in EVOH (A) is not particularly limited, and a method of reacting EVOH obtained by a saponification reaction with a monovalent epoxy compound or the like is used. As the monovalent epoxy compound, compounds represented by the following formulas (IV) to (X) are preferably used.

In the above formula, R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ independently have a hydrogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms (alkyl group, alkenyl group, etc.), and 3 carbon atoms. It represents an alicyclic hydrocarbon group of about 10 (cycloalkyl group, cycloalkenyl group, etc.) or an aliphatic hydrocarbon group of 6 to 10 carbon atoms (phenyl group, etc.). Further, i, j, k, p and q each independently represent an integer of 1 to 8. However, when R ¹⁷ is a hydrogen atom, R ¹⁸ has a substituent other than the hydrogen atom.

Examples of the monovalent epoxy compound represented by the formula (IV) include epoxy ethane (ethylene oxide), epoxy propane, 1,2-epoxy butane, 2,3-epoxy butane, and 3-methyl-1,2-epoxy butane. , 1,2-Epoxypentane, 3-Methyl-1,2-Epoxypentane, 1,2-Epoxyhexane, 2,3-Epoxyhexane, 3,4-Epoxyhexane, 3-Methyl-1,2-Epoxyhexane , 3-Methyl-1,2-Epoxy Heptane, 4-Methyl-1,2-Epoxy Heptane, 1,2-Epoxy Octane, 2,3-Epoxy Octane, 1,2-Epoxy Nonan, 2,3-Epoxy Nonan , 1,2-epoxy decane, 1,2-epoxy dodecane, epoxy ethylbenzene, 1-phenyl-1,2-epoxy propane, 3-phenyl-1,2-epoxy propane and the like. Examples of the monovalent epoxy compound represented by the formula (V) include various alkyl glycidyl ethers and the like. Examples of the monovalent epoxy compound represented by the formula (VI) include various alkylene glycol monoglycidyl ethers. Examples of the monovalent epoxy compound represented by the formula (VII) include various alkenyl glycidyl ethers. Examples of the monovalent epoxy compound represented by the formula (VIII) include various epoxy alkanols such as glycidol. Examples of the monovalent epoxy compound represented by the formula (IX) include various epoxy cycloalkanes. Examples of the monovalent epoxy compound represented by the formula (X) include various epoxy cycloalkenes.

Among the monovalent epoxy compounds, an epoxy compound having 2 to 8 carbon atoms is preferable. In particular, from the viewpoint of ease of handling and reactivity, the monovalent epoxy compound preferably has 2 to 6 carbon atoms, and more preferably 2 to 4 carbon atoms. Further, the monovalent epoxy compound is particularly preferably a compound represented by the formula (IV) or the formula (V). Specifically, from the viewpoints of reactivity with EVOH (A), processability of the obtained multilayer structure and thermoformed body, gas barrier property, etc., 1,2-epoxybutane, 2,3-epoxybutane, and epoxy Propane, epoxy ethane or glycidole is preferred, with epoxy propane or glycidole being more preferred.

In the structural unit (Z), R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ are preferably a hydrogen atom or an aliphatic hydrocarbon group having 1 to 5 carbon atoms, preferably a methyl group, an ethyl group, an n-propyl group, an isopropyl group, and the like. An n-butyl group, an isobutyl group, a tert-butyl group or an n-pentyl group is preferable.

The method for containing the structural unit (Z) in EVOH (A) is not particularly limited, and examples thereof include the methods described in JP-A-2014-304647.

EVOH (A) may be used alone or in combination of two or more.

The lower limit of the content of EVOH (A) in the resin composition of the present invention may be, for example, 50% by mass, preferably 65% by mass, more preferably 70% by mass, and 75% by mass, 80% by mass or 85% by mass. % May be more preferred. On the other hand, the upper limit of the content of EVOH (A) is preferably, for example, 95% by mass, more preferably 90% by mass, and even more preferably 85% by mass, 80% by mass, or 75% by mass. The content of EVOH (A) means the content (content ratio) in the resin composition in a dry state. Hereinafter, the same applies to the content based on the resin composition.

(Aluminum ion (B))
The aluminum ion (B) contained in the resin composition of the present invention may exist in a state of being dissociated from the anion, or may exist in the state of a salt bonded to the anion. Further, it may exist in a state of being coordinated with a group or the like (for example, a carboxy group, a hydroxyl group, etc.) possessed by EVOH (A) or another arbitrary component.

The aluminum ion (B) is usually derived from a salt, but a fatty acid aluminum salt having 5 or less carbon atoms is preferable. That is, it is preferable that a fatty acid aluminum salt having 5 or less carbon atoms is used when preparing the resin composition of the present invention. In other words, in the resin composition of the present invention, it is preferable that a fatty acid aluminum salt having 5 or less carbon atoms is added or contained as a component constituting the aluminum ion (B). Aluminum salts of fatty acids having 5 or less carbon atoms have relatively high solubility in water. Therefore, even if a fatty acid aluminum salt having 5 or less carbon atoms is added in the manufacturing process, precipitation is unlikely to occur, and a resin composition or a molded product having an excellent appearance with few foreign substances can be obtained. The added fatty acid aluminum salt having 5 or less carbon atoms may be present in the resin composition in the form of a salt in which the aluminum ion (B) and the fatty acid anion are still bonded, and the aluminum ion (B) and the fatty acid may be present. It may be present in the resin composition in a state of being dissociated from the anion.

Examples of the fatty acid aluminum salt having 5 or less carbon atoms include aluminum formate (aluminum trigitate and the like), aluminum acetate, aluminum propionate (aluminum tripropionate and the like), aluminum butyrate (aluminum tributyrate and the like) and the like. Above all, it is preferable to use at least one of aluminum acetate and aluminum tripropionate. Here, aluminum acetate is a general term for those having the structure of an aluminum salt of acetic acid typified by basic aluminum acetate, trialuminum triacetate and the like. From the viewpoint of solubility in a solvent and the like, any one or two or more of these are appropriately used.

In addition, a fatty acid aluminum salt having 6 or more carbon atoms, an aluminum salt other than the fatty acid aluminum salt (aluminum nitrate, aluminum sulfate, etc.) and the like can also be used.

In the resin composition of the present invention, the content (b) of aluminum ion (B) per 1 g of EVOH (A), that is, the content of aluminum ion (B) based on the content (mass) of EVOH (A). The lower limit of (amount of substance: number of moles) is 0.002 μmol / g, preferably 0.005 μmol / g, and more preferably 0.01 μmol / g or 0.015 μmol / g. On the other hand, the upper limit of the content (b) is 0.17 μmol / g, preferably 0.15 μmol / g, more preferably 0.10 μmol / g, and further preferably 0.05 μmol / g or 0.03 μmol / g. It may be preferable. By setting the content (b) of aluminum ions (B) per 1 g of EVOH (A) within the above range, it is possible to sufficiently improve the suppression of the generation of lumps, heat resistance and light resistance, and resistance to microplasticization. In particular, by setting this content (b) within a relatively large range, the heat resistance and light resistance and the resistance to microplasticization tend to be greatly improved. On the other hand, by setting this content (b) within a relatively small range, the effect of suppressing the generation of lumps tends to be enhanced. Further, by setting the content (b) in the above range, bending resistance and the like are also improved.

The ratio of the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) located at the polymer terminal of EVOH (A) to the content (b) of the aluminum ion (B) ((i + ii)). As the lower limit of / b), 180 is preferable, 300 is more preferable, and 1,000 is more preferable. On the other hand, as the upper limit of this ratio ((i + ii) / b), 20,000 is preferable, 15,000 is more preferable, and 10,000, 8,000, 6,000 or 4,000 may be further preferable. .. By setting the ratio ((i + ii) / b) within the above range, it is possible to more sufficiently improve the suppression of the generation of lumps, the heat resistance and light resistance, and the resistance to microplasticization. In particular, by setting this ratio ((i + ii) / b) in a relatively high range, the excess aluminum ions (B) that do not contribute to the interaction with EVOH (A) are reduced, and thus the effect of suppressing the generation of lumps is reduced. Tends to increase. On the other hand, by setting the ratio ((i + ii) / b) to a relatively low range, the heat resistance and light resistance and the resistance to microplasticization tend to be further improved. Further, by setting the above ratio ((i + ii) / b) in the above range, bending resistance and the like are also improved.

The lower limit of the content of aluminum ions (B) in the resin composition of the present invention may be, for example, 0.01 ppm, preferably 0.05 ppm, and more preferably 0.1 ppm. By setting the content of aluminum ions (B) in the entire resin composition to be equal to or higher than the above lower limit, the effect of the present invention can be further enhanced. On the other hand, as the upper limit of this content, 4 ppm is preferable, 3 ppm is more preferable, and 2 ppm or 1 ppm may be further preferable. By setting the content of aluminum ions (B) in the entire resin composition to be equal to or less than the above upper limit, it is possible to suppress the generation of lumps caused by excess aluminum ions (B).
In addition, in this specification, "ppm" indicates a mass-based content (content ratio).

(Compound (C))
The resin composition of the present invention preferably further contains compound (C). Compound (C) is at least one selected from the group consisting of cinnamon acids and conjugated polyene compounds. By further containing the compound (C) in the resin composition, it is possible to further improve the suppression of the generation of lumps, the heat resistance and light resistance, and the resistance to microplasticization. The reason for this is not clear, but it is speculated that the heat resistance and light resistance are improved by the aluminum ion (B) further interacting with the compound (C).

Examples of cinnamic acids include cinnamic acid (cis-cinnamic acid, trans-cinnamic acid, or a mixture thereof), and cinnamic acid derivatives such as cinnamic acid ester and cinnamic acid salt. The cinnamic acid derivative refers to a compound or the like obtained by reacting cinnamic acid. Examples of the cinnamic acid ester include methyl cinnamic acid, ethyl cinnamic acid and the like. Examples of the cinnamic acid salt include sodium cinnamic acid, magnesium cinnamic acid, calcium cinnamic acid and the like. Among them, it is preferable to use cinnamic acid as the cinnamic acid, particularly trans-cinnamic acid from the viewpoint of stability and price. When cinnamic acid is used, a part or all of cinnamic acid may be cinnamic acid salt by coexisting with aluminum ion (B).

The conjugated polyene compound has a structure in which carbon-carbon double bonds and carbon-carbon single bonds are alternately connected, and has a so-called conjugated double bond in which the number of carbon-carbon double bonds is two or more. It is a compound. The conjugated polyene compound may be a conjugated diene having two conjugated double bonds, a conjugated triene having three, or a conjugated polyene having a larger number. Further, the above-mentioned conjugate double bonds may be formed in a plurality of pairs in one molecule without conjugating with each other. For example, a compound having three conjugated triene structures in the same molecule, such as tung oil, is also included in the conjugated polyene compound.

The number of conjugated double bonds of the conjugated polyene compound is preferably 7 or less. Coloring can be reduced by using a conjugated polyene compound having 7 or less conjugated double bonds.

In addition to the conjugated double bond, the conjugated polyene compound includes a carboxy group and a salt thereof, a hydroxyl group, an ester group, a carbonyl group, an ether group, an amino group, an imino group, an amide group, a cyano group, a diazo group, a nitro group and a sulfone group. And other functional groups such as salts thereof, sulfonyl groups, sulfoxide groups, sulfide groups, thiol groups, phosphate groups and salts thereof, phenyl groups, halogen atoms, double bonds, triple bonds and the like.

Examples of the conjugated polyene compound include isoprene, 2,3-dimethyl-1,3-butadiene, 2,3-diethyl-1,3-butadiene, 2-t-butyl-1,3-butadiene, and 1,3-pentadiene. , 2,3-dimethyl-1,3-pentadiene, 2,4-dimethyl-1,3-pentadiene, 3,4-dimethyl-1,3-pentadiene, 3-ethyl-1,3-pentadiene, 2-methyl -1,3-Pentidiene, 3-Methyl-1,3-Pentidiene, 4-Methyl-1,3-Pentidiene, 1,3-Hexadiene, 2,4-Hexadiene, 2,5-dimethyl-2,4-Hexadiene , 1,3-octadiene, 1,3-cyclopentadiene, 1,3-cyclohexadiene, 1-phenyl-1,3-butadiene, 1,4-diphenyl-1,3-butadiene, 1-methoxy-1,3 -Butadiene, 2-methoxy-1,3-butadiene, 1-ethoxy-1,3-butadiene, 2-ethoxy-1,3-butadiene, 2-nitro-1,3-butadiene, chloroprene, 1-chloro-1 , 3-butadiene, 1-bromo-1,3-butadiene, 2-bromo-1,3-butadiene, osimene, piperylene, myrsen, farnesene, sorbic acid, sorbic acid ester, sorbate and other conjugated diene compounds;
Conjugated triene compounds such as 1,3,5-hexatriene, 2,4,6-octatriene-1-carboxylic acid, eleostearic acid, tung oil, cholecalciferol, fulvene, tropone;
Examples thereof include conjugated polyene compounds such as cyclooctatetraene, 2,4,6,8-decatetraene-1-carboxylic acid, retinol and retinoic acid.

The molecular weight of the conjugated polyene compound is usually 1,000 or less, preferably 500 or less, and more preferably 300 or less. When the molecular weight of the conjugated polyene compound is 1,000 or less, the dispersed state of the conjugated polyene compound in EVOH (A) is improved, and the appearance after melt molding is improved.

As the conjugated polyene compound, sorbic acid, sorbic acid ester, sorbate, milsen, and a mixture of two or more of these are preferable, and sorbic acid, sorbate, and a mixture thereof are more preferable. Sorbic acid, sorbic acid salt and mixtures thereof have a high effect of suppressing oxidative deterioration at high temperatures, and are also widely used industrially as food additives, and are therefore preferable from the viewpoint of hygiene and availability.

Compound (C) may be an unsaturated carboxylic acid or a salt thereof. Examples of such a compound include cinnamic acid, sorbic acid, and salts thereof. The unsaturated carboxylic acid has preferably 4 or more and 20 or less carbon atoms, and more preferably 6 or more and 10 or less carbon atoms. Compound (C) may exist in an anionic state.

In the resin composition of the present invention, the lower limit of the content (c) of the compound (C) with respect to EVOH (A) is preferably 1 ppm, more preferably 5 ppm, still more preferably 10 ppm, and even more preferably 30 ppm. By setting the content (c) of the compound (C) to be equal to or higher than the above lower limit, the effect of containing the compound (C) can be particularly sufficiently exhibited. On the other hand, the upper limit of the content (c) is preferably 1,000 ppm with respect to EVOH (A), and may be more preferably 500 ppm. When the content (c) of the compound (C) is not more than the above upper limit, the occurrence of lumps can be further reduced. The content of the compound (C) in the entire resin composition of the present invention is also preferably within the above range. The content (c) is the content (mass) of the compound (C) per 1 g of EVOH (A), and the content (mass) of the compound (C) with respect to the content (mass) of EVOH (A). ).

(Thermoplastic Elastomer (F))
The resin composition of the present invention further contains a thermoplastic elastomer (F) in order to improve the bending resistance and the like of the resin composition.

The thermoplastic elastomer (F) is not particularly limited, and polyester-based thermoplastic elastomers, polystyrene-based thermoplastic elastomers, polyolefin-based thermoplastic elastomers, and the like can be used. These may be one kind or a combination of two or more kinds. Above all, from the viewpoint of improving bending resistance, the thermoplastic elastomer (F) is preferably at least one selected from the group consisting of polystyrene-based thermoplastic elastomers and polyolefin-based thermoplastic elastomers.

Examples of the polyester-based thermoplastic elastomer (hereinafter, may be referred to as TPEE) include a multi-block copolymer having a polyester as a hard segment in the molecule and a polyether or polyester having a low glass transition temperature (Tg) as a soft segment. Be done. The TPEE can be classified into the following types according to the difference in the molecular structure, and among them, the polyester-polyester type TPEE and the polyester-polyester type TPEE are preferable.
(1) Polyester / polyether type TPEE
Generally, it is a thermoplastic elastomer using aromatic crystalline polyester as a hard segment and polyether as a soft segment.
(2) Polyester / polyester type TPEE
It is a thermoplastic elastomer using aromatic crystalline polyester as a hard segment and aliphatic polyester as a soft segment.
(3) Liquid crystal TPEE
It is a thermoplastic elastomer using rigid liquid crystal molecules as hard segments and aliphatic polyester as soft segments.

Examples of the polyester segment include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid; alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid; and aliphatic dicarboxylic acids such as succinic acid and adipic acid. Polyester segment composed of a dicarboxylic acid component and an aliphatic diol such as ethylene glycol, 1,2-propylene glycol, 1,4-butanediol; and a diol component such as an alicyclic diol such as cyclohexane-1,4-dimethanol. Can be mentioned. Examples of the polyether segment include aliphatic polyether segments such as polyethylene glycol, polypropylene glycol and polybutylene glycol.

The polystyrene-based thermoplastic elastomer is not particularly limited, but usually includes a styrene monomer polymer block (Hb) as a hard segment and a conjugated diene compound polymer block or a hydrogenated block (Sb) thereof as a soft segment. The structure of this styrene-based thermoplastic elastomer is represented by a diblock structure represented by Hb-Sb, a triblock structure represented by Hb-Sb-Hb or Sb-Hb-Sb, and a structure represented by Hb-Sb-Hb-Sb. It may be a tetrablock structure to be formed, or a polyblock structure in which a total of 5 or more Hb and Sb are linearly bonded.

The styrene-based monomer used in the styrene monomer polymer block (Hb) is not particularly limited, and examples thereof include styrene and its derivatives. Specifically, styrene, α-methylstyrene, 2-methylstyrene, 4-methylstyrene, 4-propylstyrene, 4-t-butylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4- Styrenes such as benzyl styrene, 4- (phenylbutyl) styrene, 2,4,6-trimethylstyrene, monofluorostyrene, difluorostyrene, monochlorostyrene, dichlorostyrene, methoxystyrene, t-butoxystyrene; 1-vinylnaphthalene, 2-Vinyl group-containing aromatic compounds such as vinylnaphthalene such as vinylnaphthalene; Examples thereof include vinylene group-containing aromatic compounds such as inden and acetylene. Of these, styrene is preferable. The styrene-based monomer may be only one kind or two or more kinds.

The conjugated diene compound used for the conjugated diene compound polymer block or the hydrogenated block (Sb) thereof is also not particularly limited, and examples thereof include butadiene, isoprene, 2,3-dimethylbutadiene, pentadiene, and hexadiene. can. Of these, butadiene is preferable. The conjugated diene compound may be only one kind or two or more kinds. Further, other co-monomers such as ethylene, propylene, butylene and styrene can be copolymerized. Further, the conjugated diene compound polymer block may be a hydrogenated body which is partially or completely hydrogenated.

Specific examples of the polystyrene-based thermoplastic elastomer include styrene-isopregen block copolymer (SI), styrene-butadiene diblock copolymer (SB), styrene-isoprene-styrene triblock copolymer (SIS), and styrene. Examples thereof include a butadiene / isoprene-styrene triblock copolymer (SB / IS), a styrene-butadiene-styrene triblock copolymer (SBS), and a hydrogenated product thereof. Among them, a hydrogenated product of a styrene-isopregen block copolymer (SEP), a hydrogenated product of a styrene-butadiene diblock copolymer (SEB), and a hydrogenated product of a styrene-isoprene-styrene triblock copolymer (SEPS). ), A hydrogenated product of a styrene-butadiene / isoprene-styrene triblock copolymer (SEEPS), and a hydrogenated product of a styrene-butadiene-styrene triblock copolymer (SEBS). Is preferable.

The polyolefin-based thermoplastic elastomer includes a thermoplastic elastomer having a polyolefin block such as polypropylene or polyethylene as a hard segment and a rubber block such as an ethylene-propylene-diene copolymer as a soft segment. The thermoplastic elastomer includes a blend type and an implant type, and the implant type is preferable in terms of compatibility with EVOH (A) and cost.

The thermoplastic elastomer (F) may be either a non-modified thermoplastic elastomer (F1) or a modified thermoplastic elastomer (F2), but preferably contains a modified thermoplastic elastomer (F2). By containing the modified thermoplastic elastomer (F2), for example, the reaction between EVOH (A) and the modified thermoplastic elastomer (F2) is promoted during melt-kneading, and a good phase-separated structure can be obtained without taking special extrusion conditions. A resin composition having a resin composition can be obtained. The thermoplastic elastomer (F) may contain both the non-modified thermoplastic elastomer (F1) and the modified thermoplastic elastomer (F2), or may consist only of the modified thermoplastic elastomer (F2). As the non-modified thermoplastic elastomer (F1), the resin mentioned as the above-mentioned thermoplastic elastomer can be used as it is.

The modified thermoplastic elastomer (F2) is preferably an acid-modified thermoplastic elastomer. The modified thermoplastic elastomer (F2) is obtained, for example, by modifying the non-modified thermoplastic elastomer (F1) with an unsaturated carboxylic acid or a derivative thereof. Examples of the unsaturated carboxylic acid or a derivative thereof include maleic acid, fumaric acid, itaconic acid, maleic anhydride, itaconic anhydride, maleic acid monomethyl ester, maleic acid monoethyl ester, maleic acid diethyl ester, and fumaric acid monomethyl ester. Be done. Of these, it is preferably modified with maleic anhydride. It is preferable to use such a modified thermoplastic elastomer (F2) because the compatibility between EVOH (A) and the thermoplastic elastomer (F) is enhanced, and the gas barrier property, bending resistance, and the like are further improved.

As the modified thermoplastic elastomer (F2), a modified polyester-based thermoplastic elastomer, a modified polystyrene-based thermoplastic elastomer, a modified polyolefin-based thermoplastic elastomer, or the like can be used. These may be one kind or a combination of two or more kinds. The modified thermoplastic elastomer (F2) is preferably a maleic anhydride-modified polyester-based thermoplastic elastomer, a maleic anhydride-modified polystyrene-based thermoplastic elastomer, and a maleic anhydride-modified polyolefin-based thermoplastic elastomer. Among them, from the viewpoint of improving bending resistance, the modified thermoplastic elastomer (F2) is at least one selected from the group consisting of a maleic anhydride-modified polystyrene-based thermoplastic elastomer and an anhydrous maleic acid-modified polyolefin-based thermoplastic elastomer. It is preferable to have.

The lower limit of the content ratio (F2 / F) of the modified thermoplastic elastomer (F2) with respect to the thermoplastic elastomer (F) is preferably 5% by mass, more preferably 20% by mass, and even more preferably 40% by mass. By setting the content ratio of the modified thermoplastic elastomer (F2) to the above lower limit or higher, the content ratio of the non-modified thermoplastic elastomer (F1) is relatively lowered. Although the non-modified thermoplastic elastomer (F1) is phase-separated and exists in the EVOH phase, it does not react with EVOH (A). Therefore, from the viewpoint of suppressing microplasticization, the non-modified thermoplastic elastomer (F1) is present. ) Is low, that is, the content of the modified thermoplastic elastomer (F2) is high. On the other hand, the upper limit of the content ratio (F2 / F) of the modified thermoplastic elastomer (F2) with respect to the thermoplastic elastomer (F) may be 100% by mass or 99% by mass.

It is also preferable that the thermoplastic elastomer (F) contains a polystyrene-based thermoplastic elastomer (F3) containing a halogen atom. The halogen atom is considered to be derived from the polymerization catalyst used in the production of the polystyrene-based thermoplastic elastomer, and is mainly contained at the end of the polystyrene-based thermoplastic elastomer. By containing a halogen atom at the end of the polystyrene-based thermoplastic elastomer, it reacts with EVOH and the dispersibility of the polystyrene-based thermoplastic elastomer in the EVOH phase is improved, which is preferable. Examples of the halogen atom contained in the polystyrene-based thermoplastic elastomer include chlorine, bromine, fluorine, iodine and the like, and among them, chlorine is preferable. The content of halogen atoms in the polystyrene-based thermoplastic elastomer is usually 0.005 to 3.000% by mass. Halogen atoms in polystyrene-based thermoplastic elastomers can be analyzed using an ion chromatograph. The polystyrene-based thermoplastic elastomer (F3) containing a halogen atom is more preferably a styrene-isobutylene-styrene block copolymer containing a halogen atom, and the trade name "SIBSTAR 062T" manufactured by Kaneka Co., Ltd. is mentioned. Be done. The content ratio (F3 / F) of the polystyrene-based thermoplastic elastomer (F3) containing a halogen atom to the thermoplastic elastomer (F) is preferably 20% by mass or more and 100% by mass or less, more preferably 50% by mass or more. 90% by mass or more is more preferable, and substantially 100% by mass is particularly preferable.

The lower limit of the mass ratio (F / A) of the thermoplastic elastomer (F) to EVOH (A) in the resin composition of the present invention is 5/95, preferably 8/92, more preferably 12/88, and 15 / 85 or 25/75 may be even more preferred. By setting the mass ratio (F / A) to the above lower limit or higher, bending resistance and the like can be improved. On the other hand, the upper limit of this mass ratio (F / A) is 35/65, preferably 30/70, and more preferably 25/75. By setting the mass ratio (F / A) to the above upper limit or less, the gas barrier property, heat resistance and light resistance, microplasticization resistance and the like can be further enhanced.

(Phase separation structure)
In the resin composition of the present invention, it is preferable that the particles of the thermoplastic elastomer (F) are dispersed in the matrix of EVOH (A). That is, it is preferable that the resin composition of the present invention has a sea-island structure, the sea phase is mainly composed of EVOH (A), and the island phase is mainly composed of a thermoplastic elastomer (F). As described above, since the sea phase is mainly composed of EVOH (A), the flexibility is improved while maintaining the gas barrier property.

When the resin composition of the present invention has a sea-island structure, the sea phase is mainly composed of EVOH (A), and the island phase is mainly composed of a thermoplastic elastomer (F), it is thermoplastic from the viewpoint of improving transparency. The average particle size of the island phase made of the elastomer (F) is preferably 4.5 μm or less, more preferably 3.5 μm or less, further preferably 3.0 μm or less, particularly preferably 2.5 μm or less, and most preferably 2.0 μm or less. preferable. The average particle size of the thermoplastic elastomer (F) may be 0.1 μm or more. It is preferable that the average particle size of the island phase made of the thermoplastic elastomer (F) is in the above range because the flexibility is improved and the peelability is further improved while maintaining the gas barrier property and transparency. The average particle size of the thermoplastic elastomer (F) can be adjusted by adjusting the kneading strength and the composition ratio of EVOH (A) and the thermoplastic elastomer (F).

In the resin composition of the present invention, the difference in refractive index between EVOH (A) and the thermoplastic elastomer (F) is preferably 0.05 or less, more preferably 0.04 or less, still more preferably 0.03 or less. The difference in refractive index may be 0.005 or more. When the difference in refractive index is in the above range, the transparency of the resin composition of the present invention becomes better, which is preferable.

(Antioxidant (G))
The resin composition of the present invention may further contain an antioxidant (G) in order to improve oxidative deterioration and the like of the resin composition. When the resin composition further contains an antioxidant, it is possible to suppress the generation of cracks in a molded product such as a multilayer tube formed from the resin composition.

The antioxidant (G) is a compound having an antioxidant ability. The melting point of the antioxidant (G) is not necessarily limited, but is preferably 170 ° C. or lower. When the melting point of the antioxidant (G) is 170 ° C. or lower, it is easy to melt in the extruder when the resin composition is produced by melt mixing. Therefore, it is possible to prevent the antioxidant (G) from being localized in the resin composition and coloring the high-concentration portion.

The molecular weight of the antioxidant (G) is preferably 300 or more. When the molecular weight of the antioxidant (G) is 300 or more, when the molded product is obtained from the resin composition of the present invention, the antioxidant bleeds out on the surface and the appearance of the molded product is deteriorated. It can be suppressed and the thermal stability of the resin composition is enhanced. The molecular weight is more preferably 400 or more, and particularly preferably 500 or more. On the other hand, the upper limit of the molecular weight of the antioxidant (G) is not particularly limited, but from the viewpoint of dispersibility, it is preferably 8000 or less, more preferably 6000 or less, further preferably 4000 or less, and particularly preferably 2000 or less.

As the antioxidant (G), a compound having a hindered phenol group is preferably used. While the compound having a hindered phenol group has excellent thermal stability by itself, it has the ability to capture oxygen radicals that cause oxidative deterioration, and when blended in a resin composition as an antioxidant, it causes oxidative deterioration. It has an excellent preventive effect.

As the compound having a hindered phenol group, a commercially available compound can be used, and examples thereof include the following products.
(1) "IRGANOX 1010" manufactured by BASF, melting point 110-125 ° C., molecular weight 1178, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]
(2) BASF's "IRGANOX 1076": melting point 50-55 ° C., molecular weight 531 and octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate (3) BASF's "IRGANOX 1098" : Melting point 156-161 ° C., molecular weight 637, N, N'-(hexane-1,6-diyl) bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionamide]
(4) BASF's "IRGANOX 245": melting point 76-79 ° C., molecular weight 587, triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate]
(5) "IRGANOX 259" manufactured by BASF: Melting point 104-108 ° C., molecular weight 639, 1,6-hexanediol-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate]
(6) "Sumilizer MDP-s" manufactured by Sumitomo Chemical Co., Ltd .: Melting point about 128 ° C., molecular weight 341, 2,2'-methylene-bis (4-methyl-6-tert-butylphenol)
(7) "Sumilizer GM" manufactured by Sumitomo Chemical Industry Co., Ltd .: melting point about 128 ° C., molecular weight 395, 2-tert-butyl-6- (3-tert-butyl-2-hydroxy-5-methylbenzyl) -4-methyl Phenyl acrylate (8) "Sumilizer GA-80" manufactured by Sumitomo Chemical Industry Co., Ltd .: melting point about 110 ° C., molecular weight 741, 3,9-bis [2- {3- (3-tert-butyl-4-hydroxy-5- Methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane

As the antioxidant (G), a compound having a hindered amine group is also preferably used. When a compound having a hindered amine group is blended in a resin composition as an antioxidant (G), it not only prevents thermal deterioration of EVOH (A) but also captures aldehydes generated by thermal decomposition of EVOH (A). By reducing the generation of decomposition gas, it is possible to suppress the generation of voids or bubbles during molding. Further, by capturing the aldehyde, when the resin composition of the present invention is used as a food packaging container, the point that the odor due to the aldehyde impairs the taste of the contents is also improved.

A preferred compound having a hindered amine group is a piperidine derivative, and a 2,2,6,6-tetraalkylpiperidine derivative having a substituent at the 4-position is particularly preferable. Examples of the substituent at the 4-position include a carboxyl group, an alkoxy group and an alkylamino group.

Further, although an alkyl group may be substituted at the N-position of the hindered amine group, it is preferable to use one to which a hydrogen atom is bonded because of its excellent thermal stabilization effect.

As the compound having a hindered amine group, a commercially available compound can be used, and examples thereof include the following products.
(9) BASF's "TINUVIN 770": melting point 81-85 ° C, molecular weight 481, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate (10) BASF's "TINUVIN 765": liquid Compound, molecular weight 509, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and 1,2,2,6,6-pentamethyl-4-piperidyl sebacate (mixture)
(11) BASF "TINUVIN 622LD": melting point 55-70 ° C., molecular weight 3100-4000, dimethyl 1- (2-hydroxyethyl) succinate-4-hydroxy-2,2,6,6-tetramethylpiperidine Polycondensate (12) BASF "CHIMASORB 119FL": melting point 130-140 ° C., molecular weight 2000 or more, N, N'-bis (3-aminopropyl) ethylenediamine 2,4-bis [N-butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate (13) BASF "CHIMASTORB 944LD": melting point 100-135 ° C., Molecular weight 2000-3100, poly [[6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl] (2,2,6,6-tetramethyl] -4-Piperidyl) imino] Hexamethylene (2,2,6,6-tetramethyl-4-pipeziryl) imino]]
(14) BASF's "TINUVIN 144": melting point 146-150 ° C., molecular weight 685, bis (1,2,2,6,6-pentamethyl-4-piperidyl) [[3,5-bis (1,1-) Dimethylethyl) -4-Hydrikyphenyl] Methyl] Butylmalonate (15) BASF's "UVINUL 4050H": Melting point 157 ° C., molecular weight 450, N, N'-1,6-hexanediylbis {N- (2) , 2,6,6-tetramethyl-4-piperidinyl) -formamide}
(16) "UVINUL 5050H" manufactured by BASF, a compound having a melting point of 104-112 ° C., a molecular weight of about 3500, and the following structural formula.

These compounds having a hindered phenol group or a hindered amine group may be used alone or in combination of two or more.

The lower limit of the content (g) of the antioxidant (G) with respect to EVOH (A) is preferably 0.01% by mass, more preferably 0.1% by mass, still more preferably 0.3% by mass. The upper limit of the content (g) of the antioxidant (G) is preferably 5% by mass, more preferably 3% by mass, still more preferably 1% by mass. When the content (g) of the antioxidant (G) is in the above range, the antioxidant (G) is well dispersed, and when a molded product is obtained from the resin composition of the present invention, the appearance tends to be excellent. be.

(Other ingredients)
The resin composition of the present invention can be used for resins other than EVOH (A) and thermoplastic elastomer (F), metal ions other than aluminum ions (B), and acids (compound (C)) as long as the effects of the present invention are not impaired. (Except applicable), boron compounds, plasticizers, fillers, blocking inhibitors, lubricants, stabilizers, surfactants, coloring agents, UV absorbers, antistatic agents, desiccants, cross-linking agents, reinforcing materials, etc. It may have the component of. Above all, from the viewpoint of thermal stability and adhesion to other resins, one or more of metal ions other than aluminum ion (B), acid (excluding those corresponding to compound (C)) and boron compound. It is preferable to include.

As the metal ion other than the aluminum ion (B), an alkali metal ion is preferable because the interlayer adhesiveness can be further enhanced when the resin composition of the present invention is used as a multilayer structure. These metal ions may exist in the salt state.

When the resin composition of the present invention contains such metal ions, the content thereof is preferably 1 ppm or more, more preferably 5 ppm or more, further preferably 10 ppm or more, still more preferably 20 ppm or more, and 40 ppm or more with respect to the resin composition. Is particularly preferable. The content of the metal ion other than the aluminum ion (B) is preferably 3,000 ppm or less, more preferably 1,000 ppm or less, further preferably 500 ppm or less, and particularly preferably 300 ppm or less with respect to the resin composition. When the content of the metal ion other than the aluminum ion (B) is in the above range, the multilayer structure is maintained in good interlayer adhesion, and the thermal stability when the multilayer structure is recovered and recycled is maintained. Tends to be good.

As the acid (excluding those corresponding to compound (C)), carboxylic acid or phosphoric acid is preferable from the viewpoint of enhancing thermal stability during melt molding. Examples of the carboxylic acid include formic acid, acetic acid, butyric acid, and lactic acid. As the carboxylic acid, a carboxylic acid having 4 or less carbon atoms or a saturated carboxylic acid is preferable, and acetic acid is more preferable. The acid may be present in the form of a salt or anion.

When the resin composition of the present invention contains a carboxylic acid, the content of the carboxylic acid is preferably 1 ppm or more, more preferably 10 ppm or more, still more preferably 50 ppm or more, based on the resin composition. The content of the carboxylic acid is preferably 10,000 ppm or less, more preferably 1,000 ppm or less, still more preferably 500 ppm or less. When the resin composition of the present invention contains phosphoric acid, the content of phosphoric acid is preferably 1 ppm or more, more preferably 10 ppm or more, still more preferably 30 ppm or more in terms of phosphoric acid roots with respect to the resin composition. The content of the phosphoric acid compound is preferably 10,000 ppm or less, more preferably 1,000 ppm or less, and even more preferably 300 ppm or less. When the resin composition of the present invention contains carboxylic acid or phosphoric acid within the above range, the thermal stability during melt molding tends to be good.

Examples of the boron compound include boric acid, borate ester, borate, and boron hydride.

When the resin composition of the present invention contains a boron compound, the content of the boron compound is preferably 1 ppm or more, more preferably 10 ppm or more, based on the resin composition or EVOH (A). The content of the boron compound is preferably 2,000 ppm or less, more preferably 1000 ppm or less. When the resin composition of the present invention contains a boron compound within the above range, the thermal stability during melt molding tends to be good.

The method for incorporating each of these components into the resin composition of the present invention is not particularly limited, and can be carried out by a conventionally known method.

Those corresponding to EVOH (A), aluminum ion (B), compound (C), thermoplastic elastomer (F), metal ion other than aluminum ion (B), and acid (compound (C)) in the resin composition of the present invention. The upper limit of the content of the components other than the boron compound may be preferably 10% by mass, and may be preferably 1% by mass, 0.1% by mass, 0.01% by mass or 0.001% by mass. ..

(Melt flow rate)
The lower limit of the melt flow rate at a temperature of 210 ° C. and a load of 2,160 g of the resin composition of the present invention is preferably 1.0 g / 10 minutes, more preferably 2.0 g / 10 minutes. On the other hand, the upper limit of the melt flow rate is preferably 30 g / 10 minutes, more preferably 20 g / 10 minutes, still more preferably 10 g / 10 minutes. When the melt flow rate of the resin composition of the present invention is within the above range, melt moldability, processability and the like are improved.

(Manufacturing method of resin composition)
The method for producing the resin composition of the present invention includes a method of producing a resin composition containing EVOH (A) and aluminum ion (B), and then mixing the resin composition with the thermoplastic elastomer (F). Examples thereof include a method of collectively mixing EVOH (A), aluminum ion (B) and thermoplastic elastomer (F).

As a method for producing a resin composition containing EVOH (A) and aluminum ion (B), for example, 1) a porous precipitate of EVOH (A) having a water content of 20 to 80% by mass contains an aluminum salt or the like. A method of contacting EVOH (A) with an aluminum salt or the like and then drying it. 2) A uniform solution of EVOH (A) (water / alcohol solution, etc.) contains an aluminum salt or the like. After that, it is extruded into a coagulating liquid in the form of strands, and then the obtained strands are cut into pellets and further dried. 3) A method of collectively dry-blending EVOH (A) and an aluminum salt or the like. 4) A method in which EVOH (A) and an aluminum salt or the like are collectively dry-blended and then melt-kneaded with an extruder or the like. 5) After obtaining an ethylene-vinyl ester copolymer during the production of EVOH (A). , A method of adding an aluminum salt or the like. In order to obtain the effect of the present invention more remarkably, the methods 1), 2) and 5) are preferable because the dispersibility of the aluminum ion (B) is excellent.

In the above methods 1) and 2), after an aluminum salt or the like is added, and in the method 5), after obtaining an ethylene-vinyl ester copolymer, after undergoing a saponification step and a washing step. , Usually drying is done. As such a drying method, various drying methods can be adopted. For example, fluid drying in which the substantially pellet-shaped resin composition is mechanically or while being stirred and dispersed by hot air, and the substantially pellet-shaped resin composition exerts dynamic actions such as stirring and dispersion. Examples include static drying performed without being given. Examples of the dryer for fluidized drying include a cylindrical / groove type stirring dryer, a circular tube dryer, a rotary dryer, a fluidized bed dryer, a vibrating fluidized bed dryer, and a conical rotary dryer. Examples of the dryer for static drying include a batch box type dryer as the material static type, and a band dryer, a tunnel dryer, a vertical type dryer and the like as the material transfer type. A combination of fluid drying and static drying may be performed.

Air or an inert gas (nitrogen gas, helium gas, argon gas, etc.) is used as the heating gas used during the drying treatment, and the temperature of the heating gas is 40 to 150 ° C. for productivity and EVOH (A). ) Is preferable in terms of suppressing thermal deterioration. The drying treatment time depends on the water content of the resin composition and the treatment amount thereof, but is usually preferably about 15 minutes to 72 hours in terms of productivity and prevention of thermal deterioration of EVOH (A).

Further, as the method of 4) above, there is a method of melt-kneading with, for example, a single-screw or twin-screw extruder. The melt-kneading temperature is usually 150 to 300 ° C, preferably 170 to 250 ° C.

As a method of mixing the resin composition containing EVOH (A) and aluminum ion (B) with the thermoplastic elastomer (F), a known method such as melt-kneading can be used. At this time, other components may be added and melt-kneaded or the like. As a method of collectively mixing the EVOH (A), the aluminum ion (B) and the thermoplastic elastomer (F), in the method of producing the above-mentioned mixture 3), 4) or 5), the thermoplasticity is combined with the aluminum salt. Examples thereof include a method of dry blending or adding the elastomer (F). At this time, similarly, other components may be dry-blended or added.

The resin composition of the present invention can be processed into any form such as pellets and powders and used as a molding material, and is usually in a dry state. The upper limit of the water content to the total solid content of the resin composition of the present invention may be preferably 1% by mass, more preferably 0.1% by mass or 0.01% by mass. When the resin composition of the present invention is in a dry state, good melt moldability and the like can be exhibited.

<Molded body>
The resin composition of the present invention can be molded into a molded product such as a film, a sheet, a tube, a bag, or a container by melt molding or the like. That is, the molded product of the present invention is a molded product molded from the resin composition of the present invention. The molded product of the present invention may be formed only from the resin composition of the present invention, or may have a portion formed from another material. For example, a multi-layer structure described later is also a form of a molded body.

The molded product of the present invention suppresses the generation of lumps during melt molding, has sufficient heat and light resistance, is difficult to be microplasticized after disposal, and has sufficient above-mentioned characteristics as compared with those using the same EVOH. Has been improved. Therefore, the resin composition of the present invention is particularly useful as a melt molding material. In addition, the molded product of the present invention is also excellent in bending resistance.

Examples of the method for melt molding the resin composition of the present invention include extrusion molding, cast molding, inflation extrusion molding, blow molding, melt spinning, injection molding, injection blow molding and the like. The melt molding temperature varies depending on the melting point of EVOH (A) and the like, but is preferably about 150 to 270 ° C. These compacts can also be crushed and remolded for reuse. It is also possible to stretch a film, a sheet or the like uniaxially or biaxially.

<Multi-layer structure>
The multilayer structure (laminated body) of the present invention has at least one layer made of the resin composition of the present invention. The multilayer structure usually has a layer made of the resin composition of the present invention and a layer made of other components. The lower limit of the number of layers of the multilayer structure of the present invention is, for example, 2, may be 3, and may be 4. The upper limit of the number of layers is, for example, 1,000, may be 100, or may be 20.

Examples of the layer composed of the above other components include layers composed of thermoplastic resins other than EVOH (A), paper, woven fabrics, non-woven fabrics, metal cotton strips, wood surfaces, metals and the like, and among them, other layers. A layer containing a thermoplastic resin as a main component (thermoplastic resin layer) is preferable. The layer structure of the multilayer structure of the present invention is not particularly limited, and the layer made of the resin composition of the present invention is α, the layer containing another thermoplastic resin as a main component is β, and the layer containing an adhesive resin as a main component. When expressing (adhesive layer) by γ,
β / α / β,
α / γ / β,
β / γ / α / γ / β
Such structures can be mentioned. Each of these layers may be single-layered or multi-layered.

The main component refers to the component having the highest content on a mass basis, and the content of this component is preferably 90% by mass or more, and more preferably 99% by mass or more (hereinafter,). , The same applies to the principal components.)

Further, the multilayer structure of the present invention may further have a layer (layer (δ)) containing EVOH, a thermoplastic resin and a carboxylic acid-modified polyolefin, which is exemplified in the blow-molded container described later. The multilayer structure of the present invention may also have a layered structure exemplified in a laminated stripping container, a multilayer tube, a blow-molded container, etc., which will be described later.

The method for producing the multilayer structure of the present invention is not particularly limited, and for example, a method of melt-extruding a thermoplastic resin into a molded body (film, sheet, etc.) obtained from the resin composition of the present invention, a resin composition of the present invention. A method of co-extruding and another thermoplastic resin, a method of co-injecting the resin composition of the present invention and another thermoplastic resin, a layer obtained from the resin composition of the present invention and another thermoplastic resin layer. Examples thereof include a method of laminating with a known adhesive such as an isocyanate compound and a polyester-based compound.

The thermoplastic resin that is the main component of the layer (β) includes linear low-density polyethylene, low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, and polypropylene. , Propylene-α-olefin (α-olefin having 4 to 20 carbon atoms) copolymer, olefin alone or copolymer such as polybutene and polypentene; polyester polyester elastomer such as polyethylene terephthalate, nylon-6, nylon-66. Such as polyamide, polystyrene, polyvinyl chloride, polyvinylidene chloride, acrylic resin, vinyl ester resin, polyurethane elastomer, polycarbonate, chlorinated polyethylene, chlorinated polypropylene and the like can be mentioned. Of these, polypropylene, polyethylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyamide, polystyrene and polyester are preferably used. The layer (β) may contain other optional components.

The adhesive resin as the main component of the layer (γ) may have adhesiveness to the layer of the resin composition of the present invention and the layer of another thermoplastic resin, and contains a carboxylic acid-modified polyolefin. Adhesive resin is preferred. As the carboxylic acid-modified polyolefin, a modified olefin-based polymer containing a carboxyl group obtained by chemically bonding an ethylenically unsaturated carboxylic acid, an ester thereof or an anhydride thereof to an olefin-based polymer is preferably used. Here, the olefin-based polymer means a polyolefin such as polyethylene, linear low-density polyethylene, polypropylene, or polybutene, or a copolymer of an olefin and another monomer. Of these, linear low-density polyethylene, ethylene-vinyl acetate copolymer, and ethylene-acrylic acid ethyl ester copolymer are preferable, and linear low-density polyethylene and ethylene-vinyl acetate copolymer are particularly preferable. The layer (γ) may contain other optional components.

When the multilayer structure of the present invention is a multilayer film or sheet, the average thickness is not particularly limited, and the lower limit may be, for example, 1 μm, 5 μm or 10 μm. On the other hand, the upper limit of the average thickness may be, for example, 3 mm, 1 mm, 300 μm or 100 μm. The shape of the multilayer structure is not particularly limited as long as it has a laminated structure. The form of the multi-layer structure also includes a multi-layer packaging material, a multi-layer vertical bag-filled seal bag, a multi-layer bag-in-box inner container, a multi-layer peeling container, a multi-layer tube, a multi-layer blow-molded container, and the like, which will be described later.

The molded body and the multilayer structure of the present invention suppress the generation of lumps during melt molding, have sufficient heat and light resistance, and are difficult to be microplasticized after disposal, and are compared with those using the same EVOH as described above. Each characteristic is sufficiently improved. It also has excellent bending resistance. Therefore, it is suitable for daily necessities, packaging materials, machine parts and the like used outdoors. Examples of applications in which the characteristics of the molded body and the like are particularly effectively exhibited include packaging materials, vertical bag-filled seal bags, inner containers for bag-in-boxes, laminated peeling containers, multi-layer tubes and blow-molded containers. .. Other examples include container packing materials, films, agricultural films, geomembranes, medical infusion bag materials, high pressure tank materials, gasoline tank materials, fuel containers, tire tube materials, shoe cushioning materials, organic liquid storage. Examples include tank materials, resin wallpapers, plant media, and the like.

<Packaging material>
The packaging material of the present invention is a packaging material provided with the multilayer structure of the present invention. The packaging material of the present invention may be a packaging material composed of the multilayer structure of the present invention. The packaging material is used for packaging, for example, foods, beverages, chemicals such as pesticides and pharmaceuticals, medical equipment, machine parts, industrial materials such as precision materials, and clothing. The packaging material is formed in various forms depending on the application, for example, a vertical bag filling seal bag, a vacuum packaging bag, a pouch with a spout, a laminated tube container, a lid material for a container, and the like. In particular, the packaging material has a layer containing EVOH having excellent gas barrier properties, and is also excellent in bending resistance and the like, so that it is useful as a flexible packaging material. Examples of the flexible packaging material include a vertical bag filling seal bag.

<Vertical bag filling seal bag>
The vertical bag filling seal bag of the present invention is a vertical bag filling seal bag provided with the multilayer structure of the present invention. The vertical bag filling seal bag is often used for packaging, for example, liquids, viscous bodies, powders, solid loose materials, or foods and beverages in which these are combined. The vertical bag-filled seal bag provided with the multilayer structure of the present invention has excellent bending resistance and maintains its gas barrier property when subjected to physical stress such as deformation or impact.

FIG. 4 shows a form of a vertical bag-filled seal bag (Vertical form fill seal pouch). In the vertical bag filling seal bag 1 of FIG. 4, the film material 10 is sealed on three sides of the upper end portion 11, the lower end portion 12, and the body portion 15 of the seal bag 1. In the illustrated seal bag 1, the body portion 15 is arranged at the center portion of the back surface extending from the upper end portion 11 to the lower end portion 12 so as to divide the back surface 20 into two. At the upper end portion 11, the lower end portion 12, and the body portion 15, the film material 10 is sealed in a state where the inner surfaces thereof are in contact with each other. That is, the form of the seal in the body portion 15 is so-called gassho pasting. Unlike the back surface 20, the front surface of the seal bag 1 (a surface having the same shape as the back surface on the opposite side of the back surface), which is not shown in FIG. 4, is not divided by the sealed portion and is usually a content. It is used as a surface for displaying products and products. The body portion 15 to be sealed may be arranged at either the side end portions 21 or 22, and in this case, the back surface is not divided by the sealed portion. The illustrated seal bag 1 is a vertical type of one film material 10 having a width that is twice the width of the back surface 20 (total of the width of the front surface and the width of the back surface) plus the width required for sealing at the body portion 15. It is a bag manufactured by supplying it to a bag-making filling machine. The upper end portion 11, the lower end portion 12, and the body portion 15 are all formed as linear sealing portions having no branches. As described above, in one form of the vertical bag filling seal bag, the upper end corresponding to the upper side of the front surface and the back surface of the bag, the lower end portion corresponding to the lower side, and these end portions from the upper end portion to the lower end portion. One film material is sealed and made into a bag at three parts of the body portion extending vertically to the bag. The film material 10 includes the multilayer structure of the present invention.

<Inner container for bag-in-box>
The inner container for a bag-in-box of the present invention comprises the multilayer structure of the present invention. As the inner container for the bag-in-box, for example, a container in which the liquid injection port is molded from another resin composition and the container body is formed of the above-mentioned multilayer structure can be mentioned. The bag-in-box inner container can be created, for example, by heat-sealing the film or sheet of the multilayer structure of the present invention and further heat-sealing the liquid injection port. As the heat-sealing method, normal heat-sealing conditions can be appropriately selected.

The bag-in-box is, for example, a bag-in-box containing a flexible plastic inner container (inner container for a bag-in-box) provided with a liquid injection port inside a cardboard box. The inner container for a bag-in-box is usually exposed to repeated bending during transportation and the like. When molding the inner container for the bag-in-box, processing such as increasing the thickness of the bent portion or the circumference of the sealing stopper may be performed. According to the inner container for a bag-in-box of the present invention, since the multi-layer structure of the present invention having excellent bending resistance is provided, excellent durability can be exhibited.

<Laminate peeling container>
The laminated peeling container (delamination container) of the present invention includes the multilayer structure of the present invention. The multilayer structure provided in the laminated stripping container is a layer (χ) containing a polyolefin having no polar functional group, which is directly laminated on one surface of the layer (α) made of the resin composition of the present invention. Further have. That is, the laminated stripping container has a layer structure in which the layer (χ) is directly laminated on one surface of the layer (α). With such a configuration, the peelability between the layer (α) made of the resin composition of the present invention and the layer (χ) containing polyolefin as a main component having no polar functional group becomes good, and the laminated peeling container Can be suitably used as.

The layer (χ) may be a layer substantially composed of only polyolefin having no polar functional group. The polyolefin having no polar functional group is a homopolymer or a copolymer of an olefin and has no polar functional group. Examples of the homopolymer or copolymer of the olefin include linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), ultra-low-density polyethylene (VLDPE), medium-density polyethylene (MDPE), and high-density polyethylene (high-density polyethylene). HDPE), ethylene-propylene (block or random) copolymer, polypropylene (PP), polymer of propylene and α-olefin having 4 to 20 carbon atoms, single weight of olefin such as polybutene, polypentene, polymethylpentene, etc. Combined or copolymers are preferably used. Among them, at least one selected from the group consisting of low density polyethylene (LDPE), polypropylene (PP), high density polyethylene (HDPE), and ethylene-propylene (block or random) copolymer is more preferably used.

In the multilayer structure in the laminated stripping container of the present invention, the other layer (α) made of the resin composition of the present invention adheres to the layer (β) containing a thermoplastic resin as a main component via an adhesive layer (γ). Is a preferred embodiment. With such a configuration, the flexibility and strength of the multi-layer structure of the present invention and, by extension, the laminated stripping container can be enhanced. The thermoplastic resin constituting the layer (β) is preferably a polyolefin, and this polyolefin may be the same as the polyolefin having no polar functional group, and is modified with an unsaturated carboxylic acid or a derivative thereof. It may be polyolefin or the like. Examples of the unsaturated carboxylic acid or a derivative thereof include maleic acid, fumaric acid, itaconic acid, maleic anhydride, itaconic anhydride, maleic acid monomethyl ester, maleic acid monoethyl ester, maleic acid diethyl ester, and fumaric acid monomethyl ester. Be done. These may be used alone or in combination of two or more.

Examples of the adhesive resin constituting the adhesive layer (γ) include those exemplified as an explanation of the adhesive layer in the multilayer structure of the present invention.

As the layer structure of the laminated peeling container (multilayer structure) of the present invention, the layer made of the resin composition of the present invention is α, the layer mainly composed of another thermoplastic resin is β, and the main component is an adhesive resin. When the layer (adhesive layer) to be formed is represented by γ, and the layer containing a polyolefin having no polar functional group as a main component is represented by χ,
χ / α
χ / α / γ / β
χ / α / γ / β / γ / α
χ / α / γ / β / γ / β
χ / α / γ / β / γ / α / γ / β
χ / α / γ / β / γ / β / γ / β
Such structures can be mentioned.

Examples of the method for manufacturing the laminated stripping container of the present invention include a coextrusion blow molding method and the like.

The thickness of the layer (α) made of the resin composition of the present invention constituting the laminated stripping container of the present invention is preferably 0.5 μm or more, more preferably 1 μm or more, still more preferably 5 μm or more. By setting the thickness of the layer (α) made of the resin composition to 0.5 μm or more, the gas barrier property can be enhanced. The thickness of the layer (α) made of the resin composition is preferably 1000 μm or less, more preferably 500 μm or less, still more preferably 100 μm or less. By setting the thickness of the layer (α) made of the resin composition to 1000 μm or less, the flexibility is enhanced and the peelability is improved.

The thickness of the layer (χ) containing a polyolefin having no polar functional group as a main component constituting the laminated stripping container of the present invention is preferably 25 μm or more, more preferably 30 μm or more, still more preferably 50 μm or more. The strength can be increased by setting the thickness of the layer (χ) to 25 μm or more. The thickness of the layer (χ) is preferably 5000 μm or less, more preferably 2000 μm or less, and even more preferably 1000 μm or less. By setting the thickness of the layer (χ) to 5000 μm or less, the flexibility is enhanced and the peelability is improved.

The total thickness of the multilayer structure constituting the laminated stripping container of the present invention is preferably 150 μm or more, more preferably 200 μm or more. By setting the total thickness of the multilayer structure to 150 μm or more, the strength is sufficient and the structure is less likely to be damaged. The total thickness of the multilayer structure is preferably 10,000 μm or less, more preferably 8000 μm or less, and even more preferably 6000 μm or less. Flexibility can be enhanced by setting the total thickness of the multilayer structure to 10,000 μm or less.

In the laminated peeling container of the present invention, the delamination area between the layer (α) and the layer (χ) is preferably 80 cm ² or more, more preferably 150 cm ² or more, further preferably 200 cm ² or more, and particularly preferably 220 cm ² or more. .. By setting the derami area to 80 cm ² or more, the peeling becomes more sufficient. The derami area is preferably 300 cm ² or less, more preferably 280 cm ² or less, and even more preferably 260 cm ² or less. By setting the derami area to 300 cm ² or less, it is possible to suppress the peelability from becoming too high and increase the productivity. Here, the delamination area is obtained by cutting a multilayer structure into 300 mm (width) × 350 mm (length) and creating a peeling port between the layers (α) and the layer (χ) in the central portion. It can be obtained by converting the area from the mass of the peeled portion when the tube is inserted into the tube by 50 mm and air with a pressure of 0.2 MPa is blown to peel the tube.

In the laminated peeling container of the present invention, the standard peel strength between the layer (α) and the layer (χ) is preferably 1 g / 30 mm or more, more preferably 3 g / 30 mm or more, still more preferably 5 g / 30 mm. By setting the standard peel strength to 1 g / 30 mm or more, it is possible to suppress the peelability from becoming too high and increase the productivity. The standard peel strength is preferably 12 g / 30 mm or less, more preferably 11 g / 30 mm or less, further preferably 9.5 g / 30 mm or less, and particularly preferably 9.0 g / 30 mm or less. By setting the standard peel strength to 12 g / 30 mm or less, sufficient peelability can be exhibited.

As described above, the laminated peeling container of the present invention has good peelability between the layer (α) and the layer (χ), and also has good bending resistance and the like. The laminated peeling container of the present invention can be suitably used as a laminated peeling container for foods capable of preventing deterioration of the scent, color, etc. of the contents. From the viewpoint of suppressing the peeling of the oral head, it is preferable that the laminated peeling container of the present invention has a thicker mouth than other portions. For example, the thickness of the oral cavity is preferably 0.4 mm or more, more preferably 0.5 mm or more. The upper limit of the thickness of the oral cavity may be, for example, 3 mm, and may be 2 mm or 1 mm.

<Multi-layer tube>
The multilayer tube of the present invention comprises the multilayer structure of the present invention. The multilayer tube may be a multilayer tube made of the multilayer structure of the present invention. The multi-layer pipe is a tubular multi-layer structure, and may be referred to as a multi-layer pipe, a multi-layer tube, or the like.

The multilayer tube of the present invention has a layer (α) made of the resin composition of the present invention and a layer (β) containing another thermoplastic resin as a main component, and it is preferable that the layer (β) is the innermost layer. .. Polyolefin is preferable as the thermoplastic resin that is the main component of the layer (β) at this time. By using the layer (β) as the innermost layer, deterioration of the layer (α) is suppressed, crack resistance and the like are enhanced, and gas barrier properties can be maintained for a long period of time. It is preferable that the outermost layer of the multilayer tube is a layer (β). The multilayer tube may further have a layer (γ) containing an adhesive resin as a main component, similarly to the multilayer structure described above. Specific layer configurations of the multilayer tube include (inside) β / α / β (outside), (inside) β / α / γ / β (outside), and (inside) β / γ / α / γ / β. Examples thereof include (outside), (inside) β / γ / β / α / β / γ / β (outside), (inside) β / α / β / α / β (outside).

The method for manufacturing the multilayer tube of the present invention is not particularly limited, and a conventionally known method can be adopted in the same manner as the above-mentioned method for manufacturing a multilayer structure such as coextrusion. Further, the multi-layer pipe of the present invention can also be produced by coextrusion coating the adhesive resin and the resin composition of the present invention on the outer surface of the single-layer pipe made of the layer (β).

The multilayer tube of the present invention is suitably used for automobile parts. Examples of the multi-layer pipe for automobile parts include a filler pipe and a hose for an air conditioner. The multi-layer pipe of the present invention has a layer (α) having a good gas barrier property, is excellent in bending resistance, and is unlikely to cause cracks or the like. Therefore, the multi-layer pipe is suitable as a material for automobile parts, which is required to have a high barrier property of volatile gas.

<Blow molded container>
The blow-molded container of the present invention comprises the multilayer structure of the present invention. The blow-molded container of the present invention may be a blow-molded container made of the multilayer structure of the present invention. The blow-molded container of the present invention can be used for various containers that require gas barrier properties, oil resistance, and the like. The blow-molded container has a good appearance because the generation of lumps during molding is suppressed, has sufficient heat and light resistance, and is difficult to be microplasticized after disposal, and is compared with the one using the same EVOH. Each of the above characteristics has been sufficiently improved. In addition, the blow-molded container has good bending resistance, impact resistance, and the like. Hereinafter, the blow-molded container 105 shown in FIG. 5 will be specifically described as an example. FIG. 5 is a partial cross-sectional view of the peripheral wall of the blow molded container 105.

The blow-molded container 105 of FIG. 5 includes a layer (α) 101 made of the resin composition of the present invention, a thermoplastic resin layer (layer (β) 102), an adhesive layer (layer (γ) 103), EVOH, and thermoplasticity. The layer (layer (δ) 104) containing the resin and the carboxylic acid-modified polyolefin is provided.

The layer (β) 102 is arranged on one surface side and the other surface side of the layer (α) 101, and for example, the solubility parameter calculated from the Fedors equation is 11 (cal / cm ³ ) ^1/2 . It is a layer containing the following thermoplastic resin as a main component. The layer (γ) 103 is arranged between the layer (α) 101 and the layer (β) 102, and is, for example, a layer containing a carboxylic acid-modified polyolefin as a main component. The layer (δ) is a layer containing, for example, EVOH, a thermoplastic resin having a solubility parameter calculated from the formula of Fedors of 11 (cal / cm ³ ) ^1/2 or less, and a carboxylic acid-modified polyolefin.

Specifically, in the blow-molded container 105, the layer (β) 102, the layer (γ) 103, the layer (α) 101, the layer (γ) 103, and the layer ( It has a multilayer structure in which δ) 104 and layer (β) 102 are laminated in this order.

The components of the layer (α) 101, the layer (β) 102, the layer (γ) 103, and the like are, for example, the same as each layer of the above-mentioned multilayer structure. The layer (δ) 104 is preferably formed by using the recovered products of the layer (α) 101, the layer (β) 102 and the layer (γ) 103 in the manufacturing process of the blow molded container. Examples of the recovered product include products that have failed the certification and are generated in the manufacturing process of the blow molded container. By having the layer (δ) 104 as such a recovery layer in the blow-molded container, it is possible to reuse the products that have failed the test, and the loss of the resin used in the manufacture of the blow-molded container. Can be reduced.

The blow-molded container 105 is preferably manufactured by a method including a step of blow-molding using the resin composition of the present invention. Specifically, a resin composition pellet forming the layer (α) 101, a high-density polyethylene forming the layer (β) 102, a carboxylic acid-modified polyolefin forming the layer (γ) 103, and the like, and the layer (δ). Using a recovery resin or the like forming 104, for example, layer (β) / layer (γ) / layer (α) / layer (γ) / layer (δ) at a temperature of 100 ° C. or higher and 400 ° C. or lower in a blow molding machine. Blow molding using 4 types of 6-layer parison of / layer (β) (hereinafter referred to as (inside) β / γ / α / γ / δ / β (outside)), and the temperature inside the mold is 10 ° C or higher. By cooling at 30 ° C. or lower for 10 seconds or more and 30 minutes or less, a hollow container having an average thickness of 300 μm or more and 10,000 μm or less can be formed.

The blow-molded container of the present invention is not limited to the above-mentioned form, and may have at least a layer (α). Specifically, it is not necessary to provide a layer (δ) or the like as a recovery layer. Further, other layers may be laminated. Further, the adhesive layer (γ) may be omitted by selecting a combination of resins having good adhesiveness.

When the blow-molded container includes a layer (β), it is preferable to arrange the layer (β) on the outermost layer. That is, it is preferable to arrange (inside) β / γ / α / γ / β (outside) from the inner surface of the container toward the outer surface of the container from the viewpoint of impact resistance. When a layer (δ) such as a recovery layer is included, (inside) β / γ / α / γ / δ / β (outside), (inside) β / δ / γ / α / γ / δ / β The arrangement of (outside) and (inside) δ / γ / α / γ / δ (outside) is preferable, and (inside) β / γ / α / γ / δ / β (outside) and (inside) β / δ / γ The arrangement of / α / γ / δ / β (outside) is more preferable. It should be noted that a configuration may include a layer (δ) instead of the layer (β), and in the case of an arrangement in which a plurality of layers (α) to (δ) are used, the resins constituting each layer are the same but different. You may.

A fuel container will be described as an embodiment of the blow molded container of the present invention. In addition to the blow-molded container, the fuel container may further include a filter, a fuel gauge, a baffle plate, and the like. The fuel container is preferably used as a fuel container because it is provided with the blow-molded container and is excellent in gas barrier property, oil resistance, and the like. Here, the fuel container is a fuel container mounted on an automobile, a motorcycle, a ship, an aircraft, a generator, industrial or agricultural equipment, or a portable fuel container for refueling these fuel containers, and further. Means a container for storing fuel. As a typical example, gasoline, particularly oxygen-containing gasoline blended with methanol, ethanol, MTBE, etc., is mentioned as a fuel, but heavy oil, light oil, kerosene, etc. are also included. Of these, the fuel container is particularly preferably used as a fuel container for oxygen-containing gasoline. Further, the above-mentioned laminated peeling container of the present invention when molded by blow molding is also an embodiment of the blow molding container of the present invention.

Hereinafter, the present invention will be specifically described with reference to Examples and the like, but the present invention is not limited to these Examples. The methods of measurement, calculation and evaluation were as follows.

<Quantitative (NMR method) measurement conditions for the primary structure of EVOH>
Device name: JEOL Ltd. Superconducting nuclear magnetic resonance device ECZ-600
Observation frequency: 600MHz (1H)
(1) Solvent: Deuterated dimethyl sulfoxide (DMSO-d ₆ ) Polymer concentration: 5% by mass Measurement temperature: 25 ° C, 80 ° C
Flip angle: 30 ° Total number of times: 256s
Internal standard: Tetramethylsilane (TMS)
( ₂ ) Solvent: Heavy water (D2 O) + Deuterated methanol (MeOD) (mass ratio 4/6) Polymer concentration: 5% by mass Measurement temperature: 80 ° C.
Flip angle: 30 ° Total number of times: 1024s
Internal standard: Tetramethylsilane (TMS)

<Quantification of ethylene unit content, saponification degree, terminal carboxylic acid unit content and terminal lactone ring unit content>
The ethylene unit content (Et Cont.), Kenka degree (SP), terminal carboxylic acid unit content (α) and terminal lactone ring unit content (β) of EVOH are ¹ H-NMR measurement (DMSO-d ₆ solvent). : Measurement results at 25 ° C and 80 ° C, measurement results with D2O ₊ MeOD solvent) were calculated by the following formula. The chemical shift value was based on the peak of TMS of 0 ppm. Further, in the formula, VAc, VAL and Et represent vinyl acetate unit, vinyl alcohol unit and ethylene unit, respectively.
I1, I3: Integral value of methylene hydrogen of 0.4 to 2.35 ppm (I1: DMSO-d ₆ measured value at 25 ° C, I3: measured value at DMSO-d ₆ 80 ° C)
I9 :: Integral value of methylene hydrogen of 0.4 to 2.8 ppm (measured value with D ₂ O + MeOD solvent)
I2: Integral value of methine hydrogen in vinyl alcohol unit of 3.4 to 4.0 ppm (methine hydrogen of vinyl alcohol on both sides of the same unit) (measured value at DMSO-d ₆₂₅ ° C)
I4: Integrated value of methine hydrogen in vinyl alcohol unit of 3.15 to 3.45 ppm (methine hydrogen of vinyl alcohol on both sides of the same unit) (measured value at DMSO-d ₆₈₀ ° C)
I5: Integral value derived from hydrogen of the terminal methyl group in vinyl acetate unit (measured value at DMSO-d ₆₈₀ ° C.)
I6: Integral value around 1.8 to 1.85 (measured value at DMSO-d ₆₈₀ ° C)
I7: Integral value derived from hydrogen of the methyl group in the -CH (OH) CH ₃ group present at the polymer terminal of EVOH (measured value at DMSO-d ₆₈₀ ° C.)
I8: Integral value derived from hydrogen of the methyl group in -CH ₂ CH ₃ groups present at the polymer terminal of EVOH (measured value at DMSO-d ₆₈₀ ° C.)
I10: Integral value around 0.8 to 0.95 (measured value with D ₂ O + MeOD solvent)
I11: Integral value derived from hydrogen of CH ₂ unit adjacent to the carbonyl group of terminal lactone ring unit (measured value with D ₂ O + MeOD solvent)
I12: Integral value derived from the linear COOH group of the terminal carboxylic acid group (measured value with D ₂ O + MeOD solvent)
I13, I14: Integral value derived from carboxylate of terminal carboxylic acid units (measured value with D2O ₊ MeOD solvent)
The determined ethylene unit content (Et Cont.), Terminal carboxylic acid unit content (α) and terminal lactone ring unit content (β) are all total amounts of ethylene unit, vinyl ester unit and vinyl alcohol unit. It is a percentage (mol%) of the amount (mol) of each unit with respect to (mol). However, the content of units other than ethylene units, vinyl ester units and vinyl alcohol units is extremely small as compared with these units. Therefore, the determined ethylene unit content (Et Cont.), Terminal carboxylic acid unit content (α) and terminal lactone ring unit content (β) are all units with respect to the total amount (mol) of all structural units. It is substantially equal to the percentage (mol%) of the quantity (mol).

<Measurement of melt flow rate (MFR)>
The dried resin composition pellets obtained in each reference example and reference comparative example were filled in a cylinder of Melt Indexer L244 (manufactured by Takara Kogyo Co., Ltd.) having an inner diameter of 9.55 mm and a length of 162 mm, and melted at 210 ° C. The molten resin composition was evenly loaded using a plunger having a mass of 2,160 g and a diameter of 9.48 mm. The amount of resin composition (g / 10 minutes) extruded per unit time from an orifice having a diameter of 2.1 mm provided in the center of the cylinder was measured and used as MFR.

<Sodium ion content, phosphoric acid content and boric acid content>
0.5 g of the dry resin composition pellets obtained in each reference example and reference comparative example was placed in a pressure vessel made of Teflon (registered trademark), 5 mL of concentrated nitric acid was added thereto, and the mixture was decomposed at room temperature for 30 minutes. After 30 minutes, the lid was closed, and the mixture was decomposed by heating at 150 ° C. for 10 minutes and then at 180 ° C. for 5 minutes using a wet decomposition apparatus (“MWS-2” manufactured by Actac Co., Ltd.), and then cooled to room temperature. This treatment liquid was transferred to a 50 mL volumetric flask (manufactured by TPX®) and prepared with pure water. For this solution, the contained metal was analyzed with an ICP emission spectroscopic analyzer ("OPTIMA4300DV" manufactured by PerkinElmer Co., Ltd.), and the content of sodium ion (sodium element) and phosphoric acid was contained as boric acid as a phosphoric acid root equivalent value. The amount was calculated as a boron element conversion value. For quantification, calibration curves prepared using commercially available standard solutions were used.

<Acetic acid content>
20 g of the dry resin composition pellets obtained in each Reference Example and Reference Comparative Example were put into 100 ml of ion-exchanged water, and heat-extracted at 95 ° C. for 6 hours. Using phenolphthalein as an indicator, the extract was neutralized and titrated with 1/50 standard NaOH to quantify the acetic acid content.

<Sorbic acid content>
The dried resin composition pellets obtained in each reference example and reference comparative example are frozen and pulverized, and then coarse particles are removed by a sieve (JIS standard Z8801-1 to 3) having a nominal size of 0.150 mm (100 mesh). 22 g of the pulverized product was filled in a Soxhlet extractor and extracted with 100 mL of chloroform for 16 hours. The amount of sorbic acid in the obtained chloroform extract was quantitatively analyzed by high performance liquid chromatography to quantify the content of sorbic acid in the resin composition. For quantification, a calibration curve prepared using a sorbic acid standard was used.

<Cinnamon acid content>
The dried resin composition pellets obtained in each reference example and reference comparative example are frozen and pulverized, and then coarse particles are removed by a sieve (JIS standard Z8801-1 to 3) having a nominal size of 0.150 mm (100 mesh). 22 g of the pulverized product was filled in a Soxhlet extractor and extracted with 100 mL of acetone for 16 hours. The amount of cinnamon acid in the obtained acetone extract was quantitatively analyzed by high performance liquid chromatography to quantify the content of cinnamon acid in the resin composition. For quantification, a calibration curve prepared using a cinnamic acid standard was used.

<Aluminum ion content>
15 g of the dry resin composition pellets obtained in each reference example and reference comparative example were weighed in a platinum crucible, and dry decomposition was carried out using nitric acid and sulfuric acid. 2 mL of hydrochloric acid was added to the incinerated sample, the volume was set in a 50 mL volumetric polytetrafluoroethylene (PTFE) measuring flask, and the sample solution was prepared by filtering with a PTFE filter having a pore size of 0.45 μm. Using the solution, the aluminum ion content in the resin composition was measured by high frequency plasma emission spectrometry (ICP emission spectrophotometer "IRIS AP" manufactured by Jarrel Ash).

<Synthesis Example 1> Synthesis of EVOH-A Vinyl acetate (hereinafter, may be referred to as VAc) is placed in a 200 L pressurized reaction vessel provided with a jacket, a stirrer, a nitrogen inlet, an ethylene inlet and an initiator addition port. 75.0 kg and 7.2 kg of methanol (hereinafter, may be referred to as MeOH) were charged, and nitrogen bubbling was performed for 30 minutes to replace the inside of the reaction vessel with nitrogen. Next, after adjusting the temperature in the reaction vessel to 65 ° C., ethylene was introduced so that the reaction vessel pressure (ethylene pressure) was 4.13 MPa, and 9.4 g of 2,2'-azobis (2) as an initiator was introduced. , 4-Dimethylvaleronitrile) (“V-65” manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) was added to initiate polymerization. During the polymerization, the ethylene pressure was maintained at 4.13 MPa and the polymerization temperature was maintained at 65 ° C. After 4 hours, the mixture is cooled when the conversion rate of VAc (polymerization rate based on VAc) reaches 49.7%, and 0.2 g of copper acetate dissolved in 20 kg of methanol is put into a container for polymerization. It stopped. After opening the reaction vessel and deethyleneing, nitrogen gas was bubbled to completely deethylene. The polymerization solution was then removed from the container and diluted with 20 L of MeOH. This liquid is fed from the top of the column-shaped container, MeOH vapor is fed from the bottom of the column, and the unreacted monomer remaining in the polymerization solution is removed together with the MeOH vapor to remove an ethylene-vinyl acetate copolymer (hereinafter referred to as hereafter). A MeOH solution of (sometimes referred to as EVAc) was obtained.
Next, 150 kg of a 20 mass% MeOH solution of EVAc was charged into a 300 L reaction vessel equipped with a jacket, a stirrer, a nitrogen inlet, a reflux condenser and a solution addition port. The temperature was raised to 60 ° C. while blowing nitrogen gas into this solution, and a MeOH solution having a sodium hydroxide concentration of 2 was added at a rate of 450 mL / min for 2 hours. After the addition of the sodium hydroxide MeOH solution is completed, the temperature inside the system is kept at 60 ° C., and the saponification reaction is carried out by stirring for 2 hours while flowing out the MeOH and methyl acetate produced by the saponification reaction to the outside of the reaction vessel. I made it progress. Then, 8.7 kg of acetic acid was added to stop the saponification reaction.
Then, while heating and stirring at 80 ° C., 120 L of ion-exchanged water was added to allow MeOH to flow out of the reaction vessel to precipitate EVOH. EVOH precipitated by decantation was collected and crushed with a crusher. The obtained EVOH powder was put into a 1 g / L acetic acid aqueous solution (bath ratio 20: ratio of 20 L of aqueous solution to 1 kg of powder) and washed by stirring for 2 hours. This was deflated, further added to a 1 g / L acetic acid aqueous solution (bath ratio 20), and stirred and washed for 2 hours. The deflated product was put into ion-exchanged water (bath ratio 20), stirred and washed for 2 hours, and the operation of deflating the liquid was repeated 3 times for purification. The electrical conductivity of the cleaning liquid was 3 μS / cm (measured with “CM-30ET” of Toa Denpa Kogyo Co., Ltd.). Next, the crude EVOH was obtained by stirring and immersing it in 250 L of an aqueous solution containing 0.5 g / L of acetic acid and 0.1 g / L of sodium acetate for 4 hours, then removing the liquid, and drying this at 60 ° C. for 16 hours. 16.1 kg was obtained. The above operation was repeated to obtain 15.9 kg of a crude product of EVOH, whereby a total of 32.0 kg of a crude product of EVOH (EVOH-A) was obtained.

<Preparation of resin composition>
[Reference Examples 1 to 6 and Reference Comparative Examples 1 to 3]
In a 60 L stirring tank equipped with a jacket, a stirrer and a reflux condenser, 2 kg of a crude dried product of EVOH (EVOH-A) obtained in Synthesis Example 1, 0.8 kg of water and 2.2 kg of MeOH were charged, and the mixture was charged at 60 ° C. for 5 hours. It was stirred and completely dissolved. Aluminum acetate was added to the obtained solution, and the mixture was further stirred for 1 hour to completely dissolve the aluminum acetate to obtain a resin composition solution. In Reference Comparative Example 3, a resin composition solution was obtained without adding aluminum acetate. This solution is extruded into a mixed solution of water / MeOH = 90/10 cooled to -5 ° C through a gold plate having a diameter of 4 mm to precipitate in the form of strands, and the strands are cut into pellets with a strand cutter to obtain EVOH. Moisture-containing pellets were obtained. The water content of the obtained EVOH water-containing pellets was measured with a halogen moisture meter "HR73" manufactured by METTLER CORPORATION and found to be 52% by mass. The obtained water-containing pellets of EVOH were put into a 1 g / L acetic acid aqueous solution (bath ratio 20) and washed with stirring for 2 hours. This was deflated, further added to a 1 g / L acetic acid aqueous solution (bath ratio 20), and stirred and washed for 2 hours. After the liquid was removed, the acetic acid aqueous solution was updated and the same operation was performed. After washing with an aqueous acetic acid solution, the liquid was drained, put into ion-exchanged water (bath ratio 20), stirred and washed for 2 hours, and the operation of draining was repeated 3 times, and the electrical conductivity of the washing liquid was 3 μS /. Purification was carried out to cm (measured with "CM-30ET" of Toa Denpa Kogyo Co., Ltd.) to obtain a water-containing pellet of EVOH from which the catalyst residue during the saponification reaction was removed.
The hydrous pellet is put into an aqueous solution (bath ratio 20) having a sodium acetate concentration of 0.510 g / L, an acetic acid concentration of 0.8 g / L, and a phosphoric acid concentration of 0.04 g / L, and is periodically stirred for 4 hours. It was soaked and chemically treated. The pellets are deflated and dried at 80 ° C. for 3 hours and 105 ° C. for 16 hours under a nitrogen stream having an oxygen concentration of 1% by volume or less to obtain EVOH-A, acetic acid, sodium ion (sodium salt), phosphoric acid and the like. A columnar dry resin composition pellet containing aluminum ions (aluminum salt) having an average diameter of 2.8 mm and an average length of 3.2 mm was obtained. The aluminum ion content in each reference example and reference comparative example was adjusted so as to be as shown in Table 3 by adjusting the addition amount of aluminum acetate. The ethylene content of EVOH-A, the degree of saponification, the terminal lactone ring unit content, the terminal carboxylic acid unit content, the total content of the terminal carboxylic acid unit and the terminal lactone ring unit, in the obtained dry resin composition pellets, The lactone ring unit ratio, MFR, and boric acid content were quantified using the above quantification method using a dry resin composition pellet having an aluminum ion content of 0.3 ppm as a sample (hereinafter, the same applies). Table 2 shows the ethylene content, saponification degree, terminal lactone ring unit content, terminal carboxylic acid unit content, total content of terminal carboxylic acid units and terminal lactone ring unit, lactone ring unit ratio, MFR and boric acid content. Shown in. In each of the dried resin composition pellets, the sodium ion content was 90 to 110 ppm, the phosphoric acid content was 35 to 45 ppm in terms of phosphoric acid root, and the acetic acid content was 190 to 210 ppm. Further, FIG. 1 shows a ¹ H-NMR spectrum of EVOH-A measured under the conditions of the solvent DMSO-d ₆ and the measurement temperature of 25 ° C. FIG. 2 shows a ¹ H-NMR spectrum of EVOH-A measured under the conditions of the solvent DMSO-d ₆ and the measurement temperature of 80 ° C. FIG. 3 shows a ¹ H-NMR spectrum of EVOH-A measured under the conditions of solvent D ₂ O + MeOD and measurement temperature: 80 ° C.

<Synthesis Examples 2 to 11>
The amount of raw material added for the polymerization of EVOH, the polymerization conditions, the amount charged in the saponification treatment, and the addition rate of the specified sodium hydroxide MeOH solution were as shown in Table 1, and the synthesis was performed only once. In the same manner as in Example 1, 10.1 to 11.5 kg of a crude dried product of each EVOH (EVOH-B to EVOH-K) was obtained.

<Preparation of resin composition>
[Reference Examples 7 to 27, 34 and Reference Comparative Examples 4 to 23]
Reference examples except that the crude dried products of each EVOH (EVOH-B to EVOH-K) obtained in the above synthesis examples 2 to 11 were used and the components contained in the aqueous solution in the chemical treatment were as shown in Table 1. Each dry resin composition pellet was obtained in the same manner as in 1. Further, similarly to Reference Example 1 and the like, the aluminum ion content was adjusted as shown in Tables 3 to 12 and 14 by adjusting the addition amount of aluminum acetate. Various measurements were also quantified using the above quantification method in the same manner as in Reference Example 1. Table 2 shows the ethylene content, saponification degree, terminal lactone ring unit content, terminal carboxylic acid unit content, total content of terminal carboxylic acid units and terminal lactone ring unit, lactone ring unit ratio, MFR and boric acid content. Shown in. The sodium ion content of each of the dried resin composition pellets was 90 to 110 ppm, the phosphoric acid content was 35 to 45 ppm in terms of phosphoric acid root, and the acetic acid content was 190 to 210 ppm.

<Preparation of resin composition>
[Reference Examples 28 to 33 and Reference Comparative Example 24]
2 kg of a crude dried product of EVOH (EVOH-A) obtained in Synthesis Example 1, 0.8 kg of water and 2.2 kg of MeOH were charged and stirred at 60 ° C. for 5 hours to completely dissolve them. Aluminum acetate, sorbic acid or cinnamic acid was added to the obtained solution, and the mixture was further stirred for 1 hour to completely dissolve the aluminum acetate and sorbic acid or cinnamic acid to obtain a resin composition solution. In Reference Comparative Example 24, aluminum acetate was not added and only sorbic acid was added to obtain a resin composition solution. The subsequent treatment was the same as in Reference Example 1 to obtain pellets of each dry resin composition. By adjusting the addition amount of aluminum acetate for aluminum ions and adjusting the addition amount of sorbic acid or cinnamic acid, dry resin composition pellets are obtained as shown in Table 13. rice field. Various measurements were also quantified using the above quantification method in the same manner as in Reference Example 1. The sodium ion content of each of the dried resin composition pellets was 90 to 110 ppm, the phosphoric acid content was 35 to 45 ppm in terms of phosphoric acid root, and the acetic acid content was 190 to 210 ppm.

In Tables 3 to 14 and the like, the total content (mol%) of the terminal carboxylic acid units and the lactone ring unit with respect to the total amount of ethylene unit, vinyl alcohol unit and vinyl acetate unit in EVOH is converted into 1 g of EVOH. The total content (μmol / g) of the terminal carboxylic acid units and the terminal lactone ring unit per unit is also shown. In addition, the aluminum ion content (ppm) in the resin composition and the converted aluminum ion content (μmol / g) per 1 g of EVOH are also shown. Further, the ratio ((i + ii) / b) of the total content (i + ii: μmol / g) of the terminal carboxylic acid unit and the terminal lactone ring unit per 1 g of EVOH and the content of aluminum ions (b: μmol / g) per 1 g of EVOH. ) Is also shown.

<Preparation of Thermoplastic Elastomer (F) Blend Resin Composition>
[Thermoplastic Elastomer (F)]
The thermoplastic elastomer (F) used is as follows.
-Non-denatured thermoplastic elastomer (F1)
F-3: Tough Tech (registered trademark) H1041 (manufactured by Asahi Kasei Corporation, styrene-based elastomer resin)
F-7: Toughmer (registered trademark) P0280 (Mitsui Chemicals, Inc., ethylene-propylene copolymer)
-Modified thermoplastic elastomer (F2)
F-1: Modic (registered trademark) GQ131 (unsaturated carboxylic acid-modified polyester elastomer resin manufactured by Mitsubishi Chemical Corporation)
F-2: Modic® GQ430 (manufactured by Mitsubishi Chemical Corporation, unsaturated carboxylic acid-modified polyester elastomer resin)
F-4: Tough Tech (registered trademark) M1911 (manufactured by Asahi Kasei Corporation, carboxylic acid-containing styrene-based elastomer resin)
F-5: Toughmer (registered trademark) MH7020 (manufactured by Mitsui Chemicals, Inc., maleic anhydride-modified ethylene-butene copolymer)
F-6: Toughmer (registered trademark) MP0610 (manufactured by Mitsui Chemicals, Inc., maleic anhydride-modified ethylene-propylene copolymer)
-Polystyrene-based thermoplastic elastomer (F3) containing halogen atoms
F-8: Sibster® 062T-FD (SIBS, manufactured by Kaneka Corporation; styrene-isobutylene-styrene triblock copolymer)

[Examples 1 to 6, Comparative Examples 1 to 3]
The resin compositions containing EVOH-B, EVOH-C and EVOH-D obtained in Reference Examples 8, 11 and 14 and Reference Comparative Examples 4 and 5, respectively, and the above-mentioned thermoplastic elastomer are blended in the blending ratios shown in Table 15. After dry blending, the resin composition pellets were obtained by extruding under the following conditions.
Extrusion condition device: 30 mmφ twin-screw extruder L / D: 45.5
Screw: Same-direction perfect mesh extrusion temperature (° C): 220 ° C
Rotation speed: 200 rpm
Discharge rate: 20 kg / hr

<Evaluation>
<Conditions for producing a single-layer film>
The resin composition pellets obtained in Reference Examples 1 to 34, Reference Comparative Examples 1 to 24, Examples 1 to 6 and Comparative Examples 1 to 3 were formed under the following conditions to obtain a single-layer film having a thickness of 20 μm. rice field.
・ Equipment: 20 mmφ single-screw extruder (D2020, manufactured by Toyo Seiki Seisakusho Co., Ltd.)
・ L / D: 20
・ Screw: Full flight ・ Dice width: 30 cm
-Take-up roll temperature: 80 ° C
・ Screw rotation speed: 40 rpm
・ Take-up roll speed: 3.0 to 3.5 m / min ・ Set temperature: C1 / C2 / C3 / D = 180 ° C / 210 ° C / 210 ° C / 210 ° C

<Suppression of the occurrence of stuff (things)>
The number of gel-like lumps (150 μm or more that can be visually confirmed) of the single-layer film produced 50 hours after the start of operation was counted and converted to about 1.0 m ² . Judgment was made as follows based on the number of lumps per 1.0 m ² . The evaluation results are shown in Tables 3-14 and 16.
A: Less than 20 B: 20 or more and less than 40 C: 40 or more and less than 100 D: 100 or more When the evaluation results are A to B, the occurrence of lumps is sufficiently suppressed and no problem occurs. It is a level. Even when the evaluation result is C, the occurrence of lumps is suppressed, and lumps may become a problem depending on the application, but it is a usable level. When the evaluation result is D, it is a level that cannot be used due to a large amount of lumps.

<Heat and light resistance test>
The obtained single-layer film is cut into a size of 150 mm in the TD direction and 70 mm in the MD direction, attached to a PTFE sheet of the same size and a thickness of 0.3 mm, and set in a sample holder having an opening of 135 mm in width and 55 mm in height. did. Using the Super Xenon Weather Meter SX75 manufactured by Suga Test Instruments Co., Ltd., ultraviolet rays were continuously irradiated for 48 hours under the conditions of irradiance of 150 W / m ² , black panel temperature of 83 ° C., and humidity in the tank of 50% RH. After irradiation, the unirradiated portion around the film was cut off to obtain a film sample of a heat resistance and light resistance test having a width of 135 mm and a height of 55 mm.

<Elongation at break>
The obtained single-layer film was cut into a film sample having a size of 150 mm in the TD direction and 70 mm in the MD direction, and cuts at intervals of 15 mm were made in advance with a razor blade, and the film sample was irradiated with ultraviolet rays in the same manner as in the above heat resistance and light resistance test. The sample after irradiation with ultraviolet rays was cut into a width of 15 mm and a length of 50 mm to prepare a sample for a tensile test, and the sample was conditioned for 5 days at a temperature of 23 ° C. and a humidity of 50% RH. The sample after humidity control is subjected to a tensile test in the MD direction at a tensile tester (“AUTOGRAPH AGS-H” manufactured by Shimadzu Corporation) with a chuck distance of 30 mm and a tensile speed of 500 mm / min at N = 5, and the elongation at break is determined. Measured (evaluation after heat resistance and light resistance test). In addition, the elongation at break was measured in the same manner for the film sample that was not irradiated with ultraviolet rays (evaluation before the heat resistance and light resistance test). The reduction rate (%) of the elongation at break after the heat resistance test was calculated with respect to the elongation at break before the heat resistance test. The evaluation results are shown in Tables 3-14 and 16. It was judged that the lower the rate of decrease in elongation at break, the better the heat resistance and light resistance.

<Mass loss: Accelerated microplasticization test>
Four film samples after the heat resistance and light resistance test treatment were prepared, vacuum dried at 60 ° C. for 24 hours, and then the total dry mass (W1) of the four film samples before the pulverization treatment described later was measured. Four film samples after the heat resistance and light resistance test, 500 g of zirconia balls having a diameter of 3 mm, and 100 mL of deionized water were put into a ceramic pot mill made of alumina having a capacity of 300 mL. A closed pot mill was installed on a tabletop pot mill stand "PM-001" manufactured by AS ONE Corporation, operated at a rotation speed of 200 rpm, and crushed at room temperature for 4 hours. The contents of the crushed pot mill were taken out together with water, and the work of adding deionized water, stirring and decanting was repeated to separate the zirconia balls from the crushed material and water. The contents from which the zirconia balls had been removed were filtered under reduced pressure with a nylon mesh having an opening of 46 μm, and the filtrate was vacuum dried at 60 ° C. The mass (W2) of the crushed material of 46 μm or more remaining after being filtered with a nylon mesh was measured, and the mass loss (M) was calculated according to the following formula (i) (evaluation after the heat resistance and light resistance test).
M (%) = (W1-W2) / W1 × 100 ... (i)
In addition, the mass loss of the film sample that was not subjected to the ultraviolet irradiation test was measured in the same manner (evaluation before the heat resistance and light resistance test). The evaluation results are shown in Tables 3-14 and 16.
The value of mass loss in the evaluation after the heat resistance and light resistance test is used as an index for microplasticization, and the smaller the value, the more the microplasticization can be suppressed.

<Flexibility evaluation test>
For the 20 μm-thick single-layer films of Examples 1 to 6 and Comparative Examples 1 to 3 obtained above, "BE1006 Gelboflex tester with constant temperature bath" manufactured by Tester Sangyo Co., Ltd. was used in accordance with ASTM F392-74. In use, bending was repeated 100 times in an environment of 5 ° C. The number of pinholes after bending was measured within the range of A4 size (210 mm × 297 mm). The measurement was performed for each of the three samples, and the average value was calculated. It was evaluated that the smaller the number of pinholes after bending, the better the flexibility (flexibility). The measurement results (number of pinholes) are shown in Table 16.

<TEM observation>
Each resin composition pellet obtained in Examples 1 to 6 and Comparative Examples 1 to 3 was embedded with an epoxy resin, and a transverse section was prepared by an ultramicrotome. The obtained cross section was contacted with a 5% phosphotung acid aqueous solution for 5 minutes, dried, and then observed using a transmission electron microscope (TEM) "JEM2100" manufactured by JEOL Ltd. at an observation magnification of 5000 times. From the TEM image, those having the above-mentioned phase separation structure having a sea phase and an island phase and having an observed particle size of 0.05 μm or more are sea-island structures, and those having an observed particle size of less than 0.05 μm are minute. It was dispersed. The "sea island structure" in this embodiment means a structure having the above-mentioned phase separation structure and containing EVOH (A) in the sea phase and a thermoplastic elastomer (F) in the island phase. In the case of "fine dispersion", the presence of further phases was not confirmed in the dispersed phase. The observation results are shown in Table 16.

<Discussion>
As shown in Table 3, the resin composition of Reference Comparative Example 3 which does not contain aluminum ions has an insufficient effect of suppressing the generation of lumps, and has heat resistance and light resistance (rate of decrease in elongation at break) and microplastic. Chemical resistance (mass loss in evaluation after heat resistance and light resistance test) was also relatively large. On the other hand, the resin composition of Reference Comparative Example 1 containing a small amount of aluminum ions tended to be improved as compared with the resin composition of Reference Comparative Example 3, but the improvement effect was low. .. In addition, the resin composition of Reference Comparative Example 2 containing a large amount of aluminum ions did not improve the effect of suppressing the generation of lumps. On the other hand, the resin compositions of Reference Examples 1 to 6 in which the content (b) of aluminum ion (B) per 1 g of EVOH (A) is in the range of 0.002 μmol / g or more and 0.17 μmol / g or less. It can be seen that, as compared with the resin composition of Reference Comparative Example 1 containing a small amount of aluminum ions, the effect of suppressing lumps, heat resistance and light resistance, and resistance to microplasticization were further improved.

Tables 4 to 10 show the results using other EVOH. From these as well, similar to the results in Table 3, when the content (b) of aluminum ion (B) per 1 g of EVOH (A) is within the range of 0.002 μmol / g or more and 0.17 μmol / g or less. It can be seen that the effect of suppressing lumps, heat resistance and light resistance, and resistance to microplasticization are improved.

As shown in Table 3, when the content of aluminum ions was low (0.02 ppm, 0.001 μmol / g), the improvement effect was insufficient, so aluminum was also used in Tables 4 to 10. Based on the reference comparative example with an ion content of 0.02 ppm (0.001 μmol / g), those improved from this are evaluated as “+” and those not improved are evaluated as “-”, and these are evaluated as “-”. Shown in the table.

On the other hand, as shown in Table 11, when the total content (i + ii) of the terminal carboxylic acid unit and the terminal lactone ring unit is too small, even if the aluminum ion content is adjusted, in the evaluation after the heat resistance test. The mass loss was 14.0% by mass or more, and it did not have sufficient resistance to microplasticization. Further, as shown in Table 12, when the total content (i + ii) of the terminal carboxylic acid unit and the terminal lactone ring unit is too large, even if the content of the aluminum ion is adjusted, the evaluation of the lump is D. , The occurrence of lumps could not be sufficiently suppressed.

From the above results, when the total content (i + ii) of the terminal carboxylic acid unit and the terminal lactone ring unit per 1 g of EVOH (A) is within the range of 14 μmol / g or more and 78 μmol / g or less, per 1 g of EVOH (A). By setting the content (b) of the aluminum ion (B) in the range of 0.002 μmol / g or more and 0.17 μmol / g or less, the generation of lumps during melt molding is suppressed and sufficient heat resistance and light resistance are obtained. It can be seen that it is a resin composition that can be obtained as a molded product that has and is difficult to be microplasticized after disposal, and that a resin composition in which each of the above characteristics is sufficiently improved as compared with the one using the same EVOH can be obtained. ..

Further, as shown in Table 13, in addition to aluminum ions, at least one compound selected from the group consisting of cinnamon acids and conjugated polyene compounds having a molecular weight of 1,000 or less is further contained to achieve heat resistance and light resistance and microplastics. It can be seen that the resistance to cinnamon is further improved.

As shown in Table 14, when comparing Reference Example 8 in which EVOH using almost the same EVOH except for the lactone ring unit ratio is used with Reference Example 34, Reference Example 8 in which EVOH-B having a high lactone ring unit ratio is used is It can be seen that the heat resistance and light resistance and the resistance to microplasticization are high.

Further, as shown in Tables 15 and 16, the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) per 1 g of EVOH (A) is 14 μmol / g or more and 78 μmol / g or less. , The content (b) of aluminum ion (B) per 1 g of EVOH (A) is within the range of 0.002 μmol / g or more and 0.17 μmol / g or less, and the thermoplastic elastomer (F) is contained in a predetermined amount. When it was contained in an amount, the effect of suppressing lumps, heat resistance and light resistance, and resistance to microplasticization were improved, and the number of pinholes was small, resulting in excellent bending resistance. Further, from the comparison between Comparative Examples 1 and 2 and Example 3, the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) per 1 g of EVOH (A) is 14 μmol / g or more and 78 μmol. Bending resistance is also enhanced by setting the content (b) of aluminum ions (B) per 1 g of EVOH (A) to 0.002 μmol / g or more and 0.17 μmol / g or less. Can be confirmed. In Comparative Example 3 in which the content ratio of the thermoplastic elastomer (F) was high, the bending resistance was high, but the heat resistance and light resistance and the resistance to microplasticization were inferior.

In Table 16, the effect of suppressing lumps, heat resistance and light resistance, and resistance to microplasticization are based on Comparative Example 1 in Table 16, and those improved from this are indicated by "+", and those not improved are indicated by "+". It was evaluated as "-" and these are shown in each table. However, from the comparison between Comparative Example 1 and Example 3 in Table 16, the resin composition of each example has a lump-suppressing effect, heat resistance and light resistance, and micro, as compared with the one using the same type of EVOH. It can also be confirmed that the plasticization resistance is improved.

Further, in addition to the resin compositions of Examples 1 to 6, the resin composition of the present invention can be prepared, for example, by mixing a predetermined amount of the thermoplastic elastomer (F) with the resin compositions of Reference Examples 1 to 34. From the results of Reference Examples 1 to 34, such a resin composition also suppresses the generation of lumps during melt molding, has sufficient heat resistance and light resistance, and is difficult to be microplasticized after disposal. It is clear that the resin composition obtained by the body is sufficiently improved in each of the above-mentioned properties as compared with the resin composition using the same EVOH. Therefore, even in the case of a resin composition having a composition containing EVOH (A), aluminum ion (B) and a thermoplastic elastomer (F) other than the resin compositions of Examples 1 to 6, the carboxylic acid unit (I) per 1 g. ) And the total content (i + ii) of the lactone ring unit (II) of 14 μmol / g or more and 78 μmol / g or less of EVOH (A), and the content of aluminum ion (B) per 1 g of EVOH (A) (b). ) Is adjusted within the range of 0.002 μmol / g or more and 0.17 μmol / g or less, and the content of the thermoplastic elastomer (F) is also within the predetermined range. It is considered that it is sufficiently shown from the results of Reference Examples 1 to 34 that the chemical resistance is improved and the bending resistance is also improved.

<Making a laminated peeling container>
[Example 7]
A laminated peeling container having a main body and a head of mouth was manufactured by blow molding under the conditions shown below.
(Container shape)
Main body: φ47 mm, height 110 mm
Mouth: φ30 mm, height 16 mm
(Layer structure)
Outer layer: Non-denatured polypropylene (Noblen (registered trademark) FSX16E9, manufactured by Sumitomo Chemical Co., Ltd.)
Inner layer: Three-layer structure of outermost layer / adhesive layer / inner surface layer in order from the outer layer side Outer layer: Resin composition prepared in Example 4 Adhesive layer: Modified polyolefin (Modic (registered trademark) L522, manufactured by Mitsubishi Chemical Corporation) 1: 1 blend of LLDPE (Harmorex (registered trademark) F325N, manufactured by Japan Polyethylene Corporation) Inner surface layer: LLDPE (Harmorex (registered trademark) F325N, manufactured by Japan Polyethylene Corporation)
(Blow molding conditions)
By co-extruding each molten resin so as to have the above layer structure, a laminated parison in a molten state was produced. The lip width was adjusted during the production of the laminated parison so that the thickness of the oral cavity became thicker. The laminated parison was set in a blow molding die and molded into a desired container shape by a blow molding method. During blow molding, adjustments were made so that the thickness of the mouthpiece was sufficiently thicker than the thickness of the main body. The coextrusion conditions were adjusted so that the thickness of both the outer layer and the inner layer excluding the oral cavity was in the range of 70 to 130 μm and the ratio of the outer layer / inner layer thickness was 0.8 to 1.3. .. The conditions for blow molding were blow pressure: 0.4 MPa, mold temperature: 25 ° C., and blow time: 15 seconds.

[Measurement of oral thickness]
A section was prepared by cutting out the oral cavity of the obtained laminated stripping container with a microtome, the section was placed on a slide glass, and the thickness of the oral cavity was measured with an optical microscope. The thickness of the oral cavity was 0.5 mm.

[Peeling resistance of the oral cavity]
Preliminary peeling was performed by forming an air introduction hole in the outer layer of the main body of the laminated peeling container prepared under the above conditions and injecting air between the outer layer and the inner layer through the air introduction hole. Air was injected at a pressure of 0.3 MPa for 1.0 second. After pre-peeling, with the air introduction hole closed, the container is crushed with a force of 30 kg to apply pressure to the air between the outer and inner layers, and the interface between the outer and inner layers in the oral cavity. It was confirmed whether air leaked from the air, and evaluated according to the following criteria. The evaluation results are shown in Table 17.
A: No air leakage from the oral interface B: Air leakage from the oral interface

[Example 8]
A laminated peeling container was produced by the same method as in Example 7 except that the laminated parison was produced without adjusting the lip width and the thickness of the oral cavity and the main body was not adjusted during blow molding, and the evaluation was performed. Was done. The evaluation results are shown in Table 17.

In a container having a thick mouth as in Example 7, peeling of the mouth can be easily suppressed, but in a container having an insufficient thickness of the mouth as in Example 8, peeling of the mouth can be easily suppressed. The result was difficult to control.

[Example 9]
[Manufacturing of multi-layer pipe]
100 parts by mass of high-density polyethylene ("Yukaron Hard BX-50" manufactured by Mitsubishi Yuka Co., Ltd., density 0.952 g / cc, MFR 0.5 g / 10 minutes), 2 parts by mass of vinyltrimethoxysilane dissolved in acetone, and dicumyl. 0.2 parts by mass of the peroxide was mixed. The mixture was extruded into strands at 230 ° C. using a uniaxial screw to obtain pellets of modified polyethylene to which 1.5% by mass of vinylsilane was added. Next, in Example 2, a mixture of 100 parts by mass of the pellets and 5 parts by mass of the above-mentioned high-density polyethylene in which dibutyltin laurate was mixed in a ratio of 2% by mass was obtained in the first extruder. Put the resin composition pellets in the second extruder, and put "Admer NF408E" manufactured by Mitsui Chemicals Co., Ltd. in the third extruder as an adhesive resin, and use a circular die of 3 types and 3 layers to outside. A multi-layer pipe having a diameter of 20 mm was extruded and immediately cooled and solidified through a cooling water tank adjusted to 40 ° C. The layer structure of the multilayer pipe was such that the resin composition layer was the outermost layer, and the resin composition layer / adhesive resin layer / high-density polyethylene layer = 100 μm / 100 μm / 2000 μm. The obtained multi-layer pipe is cut to 1 m, placed in a hot air dryer at 140 ° C for 10 minutes, heated, and then bent 90 ° along a stainless steel pipe with an outer diameter of 150 mm near the center and fixed for 5 minutes for bending. Was done.

<OTR (oxygen permeability)>
20 ° C / 65% by sealing one end of the produced multi-layer pipe with a silicone rubber stopper and adhesive, and connecting the other end to an oxygen permeation measuring device (OX-TRAN-10 / 50A manufactured by Modern Control). Oxygen permeability was measured under RH conditions. The oxygen permeability was 0.048 cm ³ / m ² · day · atm, which was sufficiently practical.

The resin composition of the present invention is useful as a molding material for various molded bodies, multilayer structures and the like.

1 Vertical bag filling seal bag 10 Film material 11 Upper end 12 Lower end 15 Body 20 Back 21, 22 Side end 101 Layer (α) made of resin composition
102 Thermoplastic resin layer (β)
103 Adhesive layer (γ)
104 Layer containing EVOH, thermoplastic and carboxylic acid modified polyolefin (δ)
105 Blow-molded container 106 Container inner surface 107 Container outer surface

Claims (17)

A resin composition containing an ethylene-vinyl alcohol copolymer (A), aluminum ions (B), and a thermoplastic elastomer (F).
At least a part of the ethylene-vinyl alcohol copolymer (A) has at least one of a carboxylic acid unit (I) and a lactone ring unit (II) located at the terminal of the polymer.
The total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) per 1 g of the ethylene-vinyl alcohol copolymer (A) is 14 μmol / g or more and 78 μmol / g or less.
The content (b) of aluminum ions (B) per 1 g of the ethylene-vinyl alcohol copolymer (A) is 0.002 μmol / g or more and 0.17 μmol / g or less.
A resin composition having a mass ratio (F / A) of the thermoplastic elastomer (F) to the ethylene-vinyl alcohol copolymer (A) of 5/95 or more and 35/65 or less. The ratio ((i + ii) / b) of the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) to the content (b) of the aluminum ion (B) is 180 or more and 20,000 or less. The resin composition according to claim 1. The resin composition according to claim 1 or 2, wherein the aluminum ion (B) is derived from a fatty acid aluminum salt having 5 or less carbon atoms. Further containing at least one compound (C) selected from the group consisting of cinnamon acids and conjugated polyene compounds having a molecular weight of 1,000 or less.
The resin composition according to any one of claims 1 to 3, wherein the content (c) of the compound (C) with respect to the ethylene-vinyl alcohol copolymer (A) is 1 ppm or more and 1,000 ppm or less. Claimed that the ratio (ii / (i + ii)) of the content (ii) of the lactone ring unit (II) to the total content (i + ii) of the carboxylic acid unit (I) and the lactone ring unit (II) is 40 mol% or more. Item 2. The resin composition according to any one of Items 1 to 4. The invention according to any one of claims 1 to 5, wherein the thermoplastic elastomer (F) is at least one selected from the group consisting of a polyester-based thermoplastic elastomer, a polystyrene-based thermoplastic elastomer, and a polyolefin-based thermoplastic elastomer. Resin composition. The thermoplastic elastomer (F) contains the modified thermoplastic elastomer (F2),
The resin composition according to any one of claims 1 to 6, wherein the modified thermoplastic elastomer (F2) is a modified thermoplastic elastomer modified with an unsaturated carboxylic acid or a derivative thereof. The resin composition according to claim 7, wherein the content ratio (F2 / F) of the modified thermoplastic elastomer (F2) with respect to the thermoplastic elastomer (F) is 5% by mass or more and 100% by mass or less. The resin composition according to any one of claims 1 to 8, wherein the thermoplastic elastomer (F) contains a polystyrene-based thermoplastic elastomer (F3) containing a halogen atom. A molded product molded from the resin composition according to any one of claims 1 to 9. A multilayer structure having a layer made of the resin composition according to any one of claims 1 to 9. A packaging material comprising the multilayer structure according to claim 11. A vertical bag filling seal bag comprising the multilayer structure according to claim 11. An inner container for a bag-in-box having the multilayer structure according to claim 11. A laminated stripping container provided with the multilayer structure according to claim 11.
A laminated stripping container further comprising a layer containing a polyolefin having no polar functional group as a main component, in which the multilayer structure is directly laminated on one surface of a layer made of the resin composition. A multi-layer tube comprising the multi-layer structure according to claim 11. A blow-molded container comprising the multilayer structure according to claim 11.

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