Resin composition, molded body and multilayer body

Abstract

The present invention provides a resin composition, and a molded body and a multilayer body each using the resin composition. This resin composition contains a xylylenediamine-based polyamide resin and at least one kind of chloride that is selected from the group consisting of a chloride of an alkali metal and a chloride of an alkaline earth metal, wherein: the xylylenediamine-based polyamide resin comprises a constitutional unit derived from a diamine and a constitutional unit derived from a dicarboxylic acid; 70% by mole or more of the constitutional unit derived from a diamine is derived from xylylenediamine; and 70% by mole or more of the constitutional unit derived from a dicarboxylic acid is derived from an α, ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms.

Description

Resin composition, molded body, and multilayer body

[0001] The present invention relates to a resin composition, a molded article, and a multilayer body, and more particularly to a resin composition containing a xylylenediamine-based polyamide resin as a main component.

[0002] Due to their excellent mechanical properties, polyamide resins are widely used as materials for injection-molded articles such as automobiles and electrical and electronic components. They are also used as packaging materials for foods, beverages, medicines, electronic components, etc. Among them, polyamides obtained by polycondensation reaction of xylylenediamine and aliphatic dicarboxylic acid, particularly polyamide (MXD6) obtained from metaxylylenediamine and adipic acid, exhibit low oxygen gas permeability and are therefore used as gas barrier materials for molded articles such as films and bottles (Patent Document 1, etc.).

[0003] International Publication No. 2017 / 073560

[0004] However, with recent technological innovations, further improvements in barrier properties are required. The present invention aims to solve such problems by providing a resin composition capable of providing a molded article with excellent barrier properties, and a molded article and a multilayer article using the resin composition.

[0005] The present inventors conducted research to address the above-mentioned problems and found that the problem could be solved by blending a xylylenediamine-based polyamide resin with at least one chloride selected from the group consisting of alkali metal chlorides and alkaline earth metal chlorides. Specifically, the problem was solved by the following means. <1> A resin composition comprising a xylylenediamine-based polyamide resin and at least one chloride selected from the group consisting of alkali metal chlorides and alkaline earth metal chlorides, the xylylenediamine-based polyamide resin containing diamine-derived structural units and dicarboxylic acid-derived structural units, wherein at least 70 mol% of the diamine-derived structural units are derived from xylylenediamine and at least 70 mol% of the dicarboxylic acid-derived structural units are derived from an α,ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms. <2> The resin composition according to <1>, comprising 0.1 to 3 parts by mass of the chloride per 100 parts by mass of the xylylenediamine-based polyamide resin. <3> The resin composition according to <1> or <2>, wherein the chloride includes lithium chloride and / or magnesium chloride. <4> The resin composition according to any one of <1> to <3>, wherein the molar ratio of metaxylylenediamine to paraxylylenediamine in the xylylenediamine is 10 to 100 / 90 to 0, where the total of metaxylylenediamine and paraxylylenediamine is 100 moles. <5> The resin composition according to any one of <1> to <4>, wherein 70 mol % or more of the dicarboxylic acid-derived structural units are structural units derived from one or more of adipic acid, sebacic acid, and dodecanedioic acid.<6> The resin composition according to any one of <1> to <5>, wherein the chloride is contained in an amount of 0.1 to 3 parts by mass per 100 parts by mass of the xylylenediamine-based polyamide resin, the chloride including lithium chloride and / or magnesium chloride, the molar ratio of metaxylylenediamine to paraxylylenediamine in the xylylenediamine is 10 to 100 / 90 to 0, when the total of metaxylylenediamine and paraxylylenediamine is 100 moles, and 70 mol % or more of the dicarboxylic acid-derived structural units are structural units derived from one or more of adipic acid, sebacic acid, and dodecanedioic acid. <7> A molded article formed from the resin composition according to any one of <1> to <6>. <8> The molded article according to <7>, which is an extrusion-molded article. <9> The molded article according to <7> or <8>, which is a film. <10> The molded article according to <9>, which is stretched. <11> The molded article according to <7>, which is an injection molded article. <12> The molded article according to <7> or <11>, which is a blow molded article. <13> A multilayer body having the molded article according to any one of <7> to <12>.

[0006] According to the present invention, it is possible to provide a resin composition capable of providing a molded article having excellent barrier properties, as well as a molded article and a multi-layer article using the resin composition.

[0007] Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the following present embodiment is an example for explaining the present invention, and the present invention is not limited to this embodiment. Note that in this specification, the term "to" is used to mean that the numerical values ​​before and after it are included as lower and upper limits. In this specification, "film" refers to a generally flat molded body that is thin relative to its length and width. In this specification, various physical property values ​​and characteristic values ​​are those at 23°C unless otherwise specified. If the measurement methods, etc. described in the standards shown in this specification vary depending on the fiscal year, they shall be based on the standards as of January 1, 2023, unless otherwise specified.

[0008] The resin composition of this embodiment comprises a xylylenediamine-based polyamide resin and at least one chloride selected from the group consisting of alkali metal chlorides and alkaline earth metal chlorides. The xylylenediamine-based polyamide resin contains diamine-derived structural units and dicarboxylic acid-derived structural units, with at least 70 mol% of the diamine-derived structural units being derived from xylylenediamine, and at least 70 mol% of the dicarboxylic acid-derived structural units being derived from an α,ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms. This configuration allows for the production of resin compositions and molded articles with excellent barrier properties. In particular, resin compositions with excellent oxygen and carbon dioxide barrier properties can be obtained. This is presumably because alkali metal ions such as lithium ions and alkaline earth metal ions such as magnesium ions coordinate to the amide groups of the xylylenediamine-based polyamide resin, forming a pseudo-crosslinked structure that inhibits gas permeation. Furthermore, due to their polarity, alkali metal ions and alkaline earth metal ions are easily dispersed in the xylylenediamine-based polyamide resin. In addition, it is presumed that the use of chlorides makes it easier to provide alkali metal ions and alkaline earth metal ions.

[0009] <Xylylenediamine-Based Polyamide Resin> The resin composition of this embodiment contains a xylylenediamine-based polyamide resin. The xylylenediamine-based polyamide resin refers to a polyamide resin containing diamine-derived structural units and dicarboxylic acid-derived structural units, in which 70 mol % or more of the diamine-derived structural units are derived from xylylenediamine, and 70 mol % or more of the dicarboxylic acid-derived structural units are derived from an α,ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms. This embodiment tends to produce molded articles that maintain the strength inherent to xylylenediamine-based polyamide resins and have excellent barrier properties. More preferably, 75 mol % or more, even more preferably 80 mol % or more, even more preferably 90 mol % or more, even more preferably 95 mol % or more, and particularly preferably 99 mol % or more of the diamine-derived structural units of the xylylenediamine-based polyamide resin are derived from xylylenediamine (preferably paraxylylenediamine and / or metaxylylenediamine, more preferably metaxylylenediamine). Furthermore, the dicarboxylic acid-derived constituent units of the xylylenediamine-based polyamide resin are preferably 75 mol% or more, more preferably 80 mol% or more, even more preferably 90 mol% or more, still more preferably 95 mol% or more, and particularly preferably 99 mol% or more, of which the dicarboxylic acid-derived constituent units are derived from linear α,ω-aliphatic dicarboxylic acids having 4 to 20 carbon atoms.

[0010] In this embodiment, the molar ratio of metaxylylenediamine to paraxylylenediamine in the xylylenediamine, when the total of metaxylylenediamine and paraxylylenediamine is 100 moles, is preferably metaxylylenediamine / paraxylylenediamine is 10 to 100 / 90 to 0, more preferably 20 to 100 / 80 to 0, even more preferably 40 to 100 / 60 to 0, still more preferably 80 to 100 / 20 to 0, and even more preferably 90 to 100 / 10 to 0. By adopting such a configuration, a resin composition with excellent processability can be obtained.

[0011] Diamines other than metaxylylenediamine and paraxylylenediamine that can be used as raw diamine components for xylylenediamine-based polyamide resins include aliphatic diamines such as tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4-trimethyl-hexamethylenediamine, and 2,4,4-trimethylhexamethylenediamine; 1,3-bis( Examples of the diamine include alicyclic diamines such as bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane, bis(aminomethyl)decalin, and bis(aminomethyl)tricyclodecane; and diamines having an aromatic ring such as bis(4-aminophenyl)ether, paraphenylenediamine, and bis(aminomethyl)naphthalene, and these can be used alone or in combination of two or more.

[0012] In the xylylenediamine-based polyamide resin, preferably, 70 mol % or more of the dicarboxylic acid-derived structural units are derived from an α,ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms. The carbon number of the α,ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms is preferably 6 or more, and is preferably 18 or less, more preferably 16 or less, even more preferably 14 or less, still more preferably 13 or less, and even more preferably 12 or less. Examples of α,ω-linear aliphatic dicarboxylic acids having 4 to 20 carbon atoms suitable for use as the raw dicarboxylic acid component of xylylenediamine-based polyamide resins include succinic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, adipic acid, sebacic acid, undecanedioic acid, and dodecanedioic acid. These can be used alone or in combination of two or more. Among these, one or more of adipic acid, sebacic acid, and dodecanedioic acid are more preferred, and adipic acid is even more preferred. A preferred embodiment of the xylylenediamine-based polyamide resin in this embodiment is one in which 50 mol % or more (preferably 70 mol % or more, more preferably 90 mol % or more) of the dicarboxylic acid-derived structural units are derived from one or more of adipic acid, sebacic acid, and dodecanedioic acid (preferably adipic acid).

[0013] Examples of dicarboxylic acid components other than the above-mentioned α,ω-linear aliphatic dicarboxylic acids having 4 to 20 carbon atoms include phthalic acid compounds such as isophthalic acid, terephthalic acid, and orthophthalic acid, and isomers of naphthalenedicarboxylic acid such as 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid, and these can be used alone or in combination of two or more.

[0014] Although the xylylenediamine-based polyamide resin is primarily composed of diamine-derived structural units and dicarboxylic acid-derived structural units, other structural units are not completely excluded. It goes without saying that the resin may contain structural units derived from lactams such as ε-caprolactam and laurolactam, and aliphatic aminocarboxylic acids such as aminocaproic acid and aminoundecanoic acid. Here, "major component" refers to the structural units constituting the xylylenediamine-based polyamide resin in which the combined number of diamine-derived structural units and dicarboxylic acid-derived structural units is the largest among all structural units. In this embodiment, the combined total of the diamine-derived structural units and dicarboxylic acid-derived structural units in the xylylenediamine-based polyamide resin preferably accounts for 90% by mass or more of all structural units, more preferably 95% by mass or more, even more preferably 97% by mass or more, and even more preferably 99% by mass or more.

[0015] The melting point of the xylylenediamine-based polyamide resin is preferably 150 to 350° C., more preferably 170 to 300° C., even more preferably 180 to 280° C., and still more preferably 180 to 260° C. When the resin composition of the present embodiment contains two or more xylylenediamine-based polyamide resins, the melting point is the melting point of the xylylenediamine-based polyamide resin with the largest content.

[0016] The glass transition temperature of the xylylenediamine-based polyamide resin is preferably 40 to 100° C., more preferably 45 to 95° C., even more preferably 50 to 95° C., and still more preferably 50 to 90° C. When the resin composition of the present embodiment contains two or more xylylenediamine-based polyamide resins, the glass transition temperature is the glass transition temperature of the xylylenediamine-based polyamide resin with the largest content.

[0017] The melting point (Tm) and glass transition temperature (Tg) are values ​​measured by differential scanning calorimetry (DSC) in accordance with ISO 11357. Specifically, they can be measured according to the description in paragraph 0036 of WO 2016 / 084475, the contents of which are incorporated herein by reference. As the differential scanning calorimeter, a "DSC-60" manufactured by Shimadzu Corporation is used.

[0018] The lower limit of the number average molecular weight (Mn) of the xylylenediamine-based polyamide resin is preferably 6,000 or more, more preferably 8,000 or more, and even more preferably 10,000 or more, and is preferably 100,000 or less, more preferably 50,000 or less. When the resin composition of the present embodiment contains two or more types of xylylenediamine-based polyamide resins, the number average molecular weight is the number average molecular weight of the mixture.

[0019] The number average molecular weight (Mn) of the xylylenediamine-based polyamide resin is measured by gel permeation chromatography (GPC) using a standard polymethyl methacrylate (PMMA) equivalent value. Two columns packed with a styrene polymer are used as the packing material, and hexafluoroisopropanol (HFIP) with a sodium trifluoroacetate concentration of 2 mmol / L is used as the solvent. The resin concentration is 0.02% by mass, the column temperature is 40 ° C, the flow rate is 0.3 mL / min, and the measurement is performed using a refractive index detector (RI). The calibration curve is measured by dissolving six levels of PMMA in HFIP.

[0020] It is also preferable to use a polyamide resin produced using biomass raw materials (biomass polyamide resin) as the xylylenediamine-based polyamide resin. The use of biomass polyamide resin can reduce the environmental impact. Bioadipic acid can be used as the biomass raw material in the xylylenediamine-based polyamide resin. Mass balance certified (ISCC PLUS) adipic acid can also be used. Mass balance certification means that the amount of renewable raw materials or bio-based raw materials used at each factory or production facility, and the amount of products produced or shipped are quantified, and the quality is guaranteed.

[0021] The content of the xylylenediamine-based polyamide resin in the resin composition of this embodiment is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more. The upper limit of the content of the xylylenediamine-based polyamide resin in the resin composition of this embodiment is the amount at which all components in the resin composition other than chlorides selected from the group consisting of alkali metal chlorides and alkaline earth metal chlorides are xylylenediamine-based polyamide resin. The resin composition of this embodiment may contain only one type of xylylenediamine-based polyamide resin, or two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0022] The resin composition of this embodiment may or may not contain a polyamide resin other than the xylylenediamine-based polyamide resin. The other polyamide resin may be an aliphatic polyamide resin or a semi-aromatic polyamide resin. Examples of aliphatic polyamide resins include polyamide 4, polyamide 46, polyamide 410, polyamide 6, polyamide 66, polyamide 666, polyamide 610, polyamide 11, and polyamide 12. Examples of semi-aromatic polyamide resins include polyamide 4T, polyamide 6I, polyamide 6T, polyamide 6I / 6T, and polyamide 9T. For other polyamide resins that may be contained in the resin composition of this embodiment, please refer to the description in paragraph 0052 of JP 2023-027478 A, the contents of which are incorporated herein by reference.

[0023] When the resin composition of this embodiment contains other polyamide resins, the content thereof is preferably 1 to 10 parts by mass per 100 parts by mass of the xylylenediamine-based polyamide resin. Furthermore, the resin composition of this embodiment may be configured to be substantially free of other polyamide resins. "Substantially free of other polyamide resins" means that the content of other polyamide resins contained in the resin composition is less than 10% by mass, preferably less than 5% by mass, more preferably less than 3% by mass, and even more preferably less than 1% by mass.

[0024] <Chloride> The resin composition of this embodiment contains at least one chloride selected from the group consisting of alkali metal chlorides and alkaline earth metal chlorides. By containing such a chloride, a molded article with excellent barrier properties can be obtained. Examples of alkali metals include lithium, sodium, potassium, rubidium, cesium, and francium, with lithium, sodium, and potassium being preferred, lithium and sodium being more preferred, and lithium being even more preferred. Examples of alkaline earth metals include beryllium, magnesium, calcium, strontium, barium, and radium, with beryllium, magnesium, and calcium being preferred, magnesium and calcium being more preferred, and magnesium being even more preferred. That is, the chloride used in this embodiment preferably contains lithium chloride and / or magnesium chloride.

[0025] In this embodiment, the total content of chlorides selected from the group consisting of alkali metal chlorides and alkaline earth metal chlorides is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, per 100 parts by mass of the xylylenediamine-based polyamide resin. Depending on the application, it may be 0.4 parts by mass or more, 0.5 parts by mass or more, 0.6 parts by mass or more, or 0.8 parts by mass or more. By setting the content at or above the lower limit, gas barrier properties tend to be further improved. Furthermore, the upper limit of the chloride content is preferably 3 parts by mass or less, and may be 2.5 parts by mass or less, per 100 parts by mass of the xylylenediamine-based polyamide resin. Setting the content at or below the upper limit makes it possible to effectively suppress color deterioration of the resin composition. The resin composition of this embodiment may contain only one type of chloride, or two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0026] <Other Additives> The resin composition of this embodiment may contain thermoplastic resins, fillers, additives, etc. other than those described above. Examples of additives include oxidation reaction accelerators, release agents, impact resistance improvers, alkalis, titanium oxide, hydrolysis resistance improvers, matting agents, plasticizers, dispersants, antistatic agents, coloring inhibitors, antigelling agents, antioxidants, heat stabilizers, light stabilizers, and flame retardants. For details, see paragraphs 0130 to 0155 of Japanese Patent No. 4,894,982 and paragraphs 0047 to 0103 of International Publication No. 2021 / 241471, the contents of which are incorporated herein by reference. The other additives are preferably present in a total amount of 20.0 parts by mass or less, more preferably 10.0 parts by mass or less, even more preferably 5.0 parts by mass or less, and even more preferably 1.0 part by mass or less, per 100 parts by mass of the resin composition. Only one type of other additive may be used, or two or more types may be used in combination.

[0027] <Physical Properties of Resin Composition> The resin composition of this embodiment preferably has excellent oxygen barrier properties. For example, the stretched film formed from the resin composition of this embodiment may have an oxygen permeability coefficient of 0.040 ((cc·mm) / (m) at 23°C and a relative humidity of 60%. 2 ·day·atm)) or less, and 0.035 ((cc·mm) / (m 2 ·day·atm)) or less, and more preferably 0.030 ((cc·mm) / (m 2 The lower limit of the oxygen permeability coefficient of the stretched film formed from the resin composition of the present embodiment at 23°C and a relative humidity of 60% is 0 ((cc·mm) / (m 2 · day · atm)) or more, and 0.001 ((cc · mm) / (m 2 Even if the temperature is above 100°C, the performance requirements are still met.

[0028] The resin composition of this embodiment preferably has excellent carbon dioxide gas barrier properties. For example, the carbon dioxide gas permeability coefficient of a stretched film formed from the resin composition of this embodiment at 23°C and a relative humidity of 60% is 0.10 ((cc mm) / (m 2·day·atm)) or less, and 0.09 ((cc·mm) / (m 2 ·day·atm)) or less, and more preferably 0.08 ((cc·mm) / (m 2 It is more preferable that the lower limit of the carbon dioxide gas permeability coefficient of the stretched film formed from the resin composition of the present embodiment at 23°C and a relative humidity of 60% is 0 ((cc·mm) / (m 2 · day · atm)) or more, and 0.001 ((cc · mm) / (m 2 Even if the permeability is higher than 1 / 4 day atm), the performance requirements are fully satisfied. The oxygen permeability coefficient and carbon dioxide permeability coefficient are measured according to the method described in the Examples below. Such barrier properties are achieved by blending a chloride selected from the group consisting of alkali metal chlorides and alkaline earth metal chlorides with the xylylenediamine-based polyamide resin.

[0029] <Method for Producing Resin Composition> In this embodiment, the method for producing the resin composition is not particularly specified, and a wide variety of known methods for producing thermoplastic resin compositions can be used. Specifically, the resin composition can be produced by pre-mixing the components using various mixers such as a tumbler or a Henschel mixer, and then melt-kneading them using a Banbury mixer, roll, Brabender, single-screw extruder, twin-screw extruder, kneader, or the like. Furthermore, chlorides can also be added in advance during resin polymerization. In this embodiment, melt-kneading using a twin-screw extruder is preferred.

[0030] Alternatively, for example, a resin composition can be produced by premixing only some of the components without premixing the components, feeding the mixture into an extruder using a feeder, and melt-kneading the mixture.Furthermore, for example, a composition obtained by premixing some of the components, feeding the mixture into an extruder, and melt-kneading the mixture can be used as a masterbatch, and pellets can be produced by mixing the masterbatch again with the remaining components and melt-kneading the mixture.

[0031] <Molded Article> The molded article of this embodiment is formed from the resin composition or pellets of this embodiment. For example, the molded article of this embodiment may be formed by melt-kneading the components and then directly molding them using various molding methods, or the components may be melt-kneaded and pelletized, and then re-melted and molded using various molding methods. The method for producing the molded article of this embodiment is not particularly limited. One example is an extrusion-molded article (e.g., a film) molded by extrusion molding. Another example is an injection-molded article molded by injection molding. Yet another example is a hollow-molded article molded by blow molding.

[0032] The shape of the molded body of the present embodiment is not particularly limited and can be appropriately selected depending on the use and purpose of the molded body. Examples include a film shape (which includes a plate shape, a plate shape, and a sheet shape), a cylindrical shape, an annular shape, a circular shape, an elliptical shape, a gear shape, a polygonal shape, an irregular shape, a hollow shape, a frame shape, a box shape, and a panel shape, and a film shape is preferred.

[0033] The application field of the molded article of this embodiment is not particularly limited, and it is widely used in automobile and other transportation equipment parts, general machine parts, precision machine parts, electronic and electrical equipment parts, office automation equipment parts, building materials and housing-related parts, medical devices, leisure and sporting goods, play equipment, medical supplies, daily necessities such as food packaging films, defense and aerospace products, etc.

[0034] <Multilayer Body> Next, the multilayer body of this embodiment will be described. The multilayer body of this embodiment includes the molded article of this embodiment. Examples of layers other than the multilayer body (other layers) included in the multilayer body of this embodiment include thermoplastic resin layers such as polyester resin layers and polyolefin resin layers. The polyester resin is preferably polyethylene terephthalate resin, and the polyolefin resin is more preferably polypropylene resin or polyethylene resin. The number of layers constituting the multilayer body is preferably at least three. In this embodiment, an example is a configuration including at least two polyester resin layers and / or polyolefin resin layers and at least one layer formed from the resin composition of this embodiment. In the multilayer body of this embodiment, the layer formed from the resin composition of this embodiment preferably functions as a barrier layer. More specifically, the number of layers constituting the multilayer body is more preferably 3 to 10 layers, and even more preferably 3 to 5 layers. The multilayer body of this embodiment may also include an oxygen absorbing layer, an adhesive layer, a gas barrier layer other than the polyamide resin layer, a protective layer, a design layer, etc. For details, please refer to the descriptions in paragraphs 0012 to 0046 of JP 2021-080025 A, the descriptions in JP 2017-114532 A, and the descriptions in paragraphs 0120 to 0122 of JP 2016-169291 A, the contents of which are incorporated herein by reference.

[0035] <Stretching> The molded article or multilayer body of this embodiment is preferably stretched. The stretching may be uniaxial or biaxial. When stretching, a film-like molded article may be stretched. Alternatively, biaxial stretch blow molding, which is performed when molding a container such as a bottle, may be used.

[0036] When a film formed from the resin composition of the present embodiment is stretched, its thickness (thickness of the stretched film) may be appropriately selected depending on the application and is not particularly limited, but from the viewpoints of strength, impact resistance, barrier properties, etc., the lower limit is preferably 10 μm or more, more preferably 15 μm or more, and even more preferably 20 μm or more. The upper limit is preferably 50 μm or less, more preferably 40 μm or less, and even more preferably 35 μm or less.

[0037] When the film of this embodiment is uniaxially stretched, the stretching ratio is preferably 1.1 times or more, more preferably 2.0 times or more, and even more preferably 2.5 times or more. There is no particular upper limit, but it is preferably 20.0 times or less. When the film of this embodiment is biaxially stretched, the stretching ratio is preferably 1.1 times or more, more preferably 2.0 times or more, and even more preferably 4.0 times or more. There is no particular upper limit, but it is preferably 20.0 times or less.

[0038] <Multilayer Container> The multilayer body of the present embodiment is preferably used as a multilayer container. The shape of the multilayer container is not particularly limited, and may be, for example, a molded container such as a bottle, a cup, a tube, a tray, or Tupperware, or a bag-like container such as a pouch, a stand-up pouch, or a zippered storage bag.

[0039] The objects to be stored in the multilayer container of this embodiment are not particularly limited, and examples thereof include food, cosmetics, pharmaceuticals, toiletries, mechanical, electrical, and electronic parts, oils, and resins, but the container is particularly suitable for use as a container for storing food. Examples include processed seafood products, processed livestock products, rice, and liquid foods. The container is particularly suitable for storing foods that are susceptible to oxygen. For details, please refer to paragraphs 0032 to 0035 of JP 2011-37199 A, the contents of which are incorporated herein by reference. The food to be filled is not particularly limited, but specific examples include beverages such as vegetable juice, fruit juice, tea, coffee and coffee drinks, milk and dairy drinks, mineral water, ionic drinks, alcoholic beverages, lactic acid bacteria drinks, and soy milk; gel foods such as tofu, egg tofu, jellies, puddings, mizu yokan, mousse, yogurt, and almond tofu; condiments such as sauce, soy sauce, ketchup, noodle soup, sauce, vinegar, mirin, dressing, jam, mayonnaise, miso, pickle base, and grated spices; salami, ham, sausage, yakitori, Examples of processed meat products include meatballs, hamburgers, roast pork, and beef jerky; processed seafood products such as kamaboko, boiled shellfish, boiled fish, and chikuwa; processed rice products such as porridge, cooked rice, mixed rice, and red rice; sauces such as meat sauce, mapo sauce, pasta sauce, curry, stew, and hayashi sauce; processed dairy products such as cheese, butter, cream, and condensed milk; processed egg products such as boiled eggs and soft-boiled eggs; boiled vegetables and boiled beans; prepared dishes such as fried, steamed, stir-fried, simmered, and grilled foods; pickles; noodles and pasta such as udon, soba, and spaghetti; and fruits in syrup.

[0040] In addition, the multilayer body, multilayer container, and manufacturing methods thereof of this embodiment can be understood by referring to the descriptions in JP 2016-198912 A, JP 2016-169027 A, and JP 60-232952 A, the contents of which are incorporated herein by reference, within the scope of the spirit of this embodiment.

[0041] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

[0042] 1. Raw Materials <Synthesis of MXD10> 60.00 mol of precisely weighed sebacic acid was placed in a jacketed reactor equipped with a stirrer, partial condenser, condenser, thermometer, dropping tank, and nitrogen gas inlet tube. The atmosphere was thoroughly purged with nitrogen and the temperature was raised to 170°C under a small nitrogen stream to dissolve the sebacic acid and create a uniform fluid state. 60 mol of meta-xylylenediamine was added dropwise to the reactor over 160 minutes with stirring. During this time, the internal pressure of the reaction system was maintained at atmospheric pressure, and the internal temperature was continuously raised to 240°C. Water distilled with the dropwise addition of meta-xylylenediamine was removed from the system via the partial condenser and condenser. After the dropwise addition of meta-xylylenediamine was completed, the liquid temperature was maintained at 250°C and the reaction was continued for 10 minutes. The internal pressure of the reaction system was then continuously reduced to 600 Torr over 10 minutes, after which the reaction was continued for 20 minutes. During this time, the reaction temperature was continuously raised to 260°C. After the reaction was completed, the reactor was pressurized with nitrogen gas at 0.3 MPa, and the polymer was removed as a strand from a nozzle at the bottom of the polymerization vessel. After water cooling, the polymer was cut into pellets to obtain pellets of a melt-polymerized product. The resulting pellets were charged at room temperature into a tumbler (rotary vacuum vessel) equipped with a heat medium heating jacket. While rotating the tumbler, the vessel was reduced in pressure (0.5 to 10 Torr), and the circulating heat medium was heated to 180°C. The pellet temperature was raised to 170°C and maintained at that temperature for 5 hours. Nitrogen was then introduced again to restore normal pressure, and cooling was initiated. When the pellet temperature reached 70°C or below, the pellets were removed from the vessel, yielding a solid-state polymerized product. The resulting polyamide resin had a melting point of 190°C and a glass transition temperature of 60°C.

[0043] <Synthesis of Polyamide MP12> 60.00 mol of precisely weighed dodecanedioic acid was placed in a jacketed reactor equipped with a stirrer, partial condenser, condenser, thermometer, dropping tank, and nitrogen gas inlet tube. The atmosphere was thoroughly purged with nitrogen and the temperature was raised to 180 °C under a small nitrogen stream to dissolve the dodecanedioic acid and create a uniform fluid state. 60 mol of para- / meta-xylylenediamine, consisting of 30 mol% para-xylylenediamine and 70 mol% meta-xylylenediamine as diamine components, was added dropwise over 160 minutes with stirring. During this time, the internal pressure of the reaction system was maintained at atmospheric pressure, and the internal temperature was continuously raised to 250 °C. Water distilled with the addition of para- / meta-xylylenediamine was removed from the system via the partial condenser and condenser. After the dropwise addition of para- / meta-xylylenediamine was completed, the liquid temperature was maintained at 250 °C and the reaction was continued for 10 minutes. The pressure inside the reaction system was then continuously reduced to 600 Torr over 10 minutes, and the reaction was continued for 20 minutes. During this time, the reaction temperature was continuously raised to 260°C. After the reaction was completed, the reactor was pressurized with 0.3 MPa of nitrogen gas, and the polymer was removed as a strand from a nozzle at the bottom of the polymerization vessel. After water cooling, the polymer was cut into pellets to obtain pellets of the melt-polymerized product. The resulting pellets were placed at room temperature in a tumbler (rotary vacuum vessel) equipped with a heat medium heating jacket. While rotating the tumbler, the vessel was evacuated to a reduced pressure (0.5-10 Torr), and the circulating heat medium was heated to 190°C. The pellet temperature was raised to 180°C and maintained at that temperature for 5 hours. Nitrogen was then introduced again to restore normal pressure, and cooling was initiated. When the pellet temperature reached 70°C or below, the pellets were removed from the vessel, yielding a solid-state polymerized product. The melting point of the resulting polyamide resin (MP12) was 216°C and the glass transition temperature was 57°C.

[0044] MXD6: Nylon MXD6, S6007, manufactured by Mitsubishi Gas Chemical Company, Inc., melting point was 237° C. and glass transition temperature was 85° C. PA6: Polyamide 6, manufactured by Ube Industries, Ltd., UBE Nylon 1022B, polyamide 6 melting point was 225° C. and glass transition temperature was 40° C.

[0045] MgCl ２ : Reagent manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. LiCl: Reagent manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.

[0046] 2. Examples 1 to 9 and Comparative Examples 1 to 4 The polyamide resins and chlorides shown in Table 1 (proportions of each component are in parts by mass) were dry-blended and fed to a twin-screw melt-kneader (manufactured by The Japan Steel Works, Ltd., model: TEX34αIII) and melt-kneaded at a cylinder temperature of 240°C to 260°C. The mixture was then fed to a single-screw extruder with a T-die (manufactured by Plastics Engineering Research Institute, PTM-30) and melt-extruded through the die at an extrusion temperature of 250°C. Specifically, the resin composition obtained by melt-kneading each component was extruded to obtain unstretched films with a width of 175 mm and thicknesses of 50 μm and 180 μm. The 180 μm film was then cut into 90 mm squares. Thereafter, using a batch-type biaxial stretching apparatus (tenter method, EX10-S5, manufactured by Toyo Seiki Seisakusho, Ltd.), the film was stretched in both the MD and TD directions while heated in an atmospheric atmosphere at 100°C, with a stretch ratio of 3.5 times in the MD and 3.5 times in the TD, to obtain a stretched film with a thickness of 15 μm. During this stretching process, a relaxation operation was performed midway, with an MD relaxation rate of 3% and a TD relaxation rate of 3%. The stretching temperature was 100°C. After stretching, the film was heat-set. The heat-set temperature was -20°C below the melting point of each resin, and the heat-set time was 30 seconds.

[0047] <Oxygen Transmission Coefficient (OTC) (Oxygen Barrier Property)> The oxygen transmission coefficient (OTR) of the unstretched film and stretched film obtained above was measured in accordance with ASTM D3985 using an oxygen transmission coefficient measuring device at 23°C under an atmosphere of 60% relative humidity. The unit pressure for OTR and OTC was 1 atm, and the unit transmission time was 24 hours. The oxygen transmission coefficient (OTC) is calculated as follows: OTC = OTR × measured film thickness / 1000 Unit of OTR: cc / (m ２ ・day・atm) OTC unit cc・mm / (m ２ ·day·atm) Measurement film thickness unit: μm The oxygen transmission rate (OTR) was measured using an oxygen transmission rate measuring device (manufactured by MOCON, product name: "OX-TRAN (registered trademark) 2 / 22").

[0048] <Carbon dioxide gas permeability coefficient (carbon dioxide gas barrier property)> The carbon dioxide gas permeability of the stretched film obtained above was measured in accordance with JIS K 7126-1:2006 using a gas permeability measuring device at 23°C under an atmosphere of 60% relative humidity. The unit pressure for the carbon dioxide gas permeability and carbon dioxide gas permeability coefficient was 1 atm, and the unit permeation time was 24 hours. The carbon dioxide gas permeability coefficient is calculated as follows: Carbon dioxide gas permeability coefficient = Carbon dioxide gas permeability × Measured film thickness / 1000 Unit of carbon dioxide gas permeability: cc / (m ２ · day · atm) Unit of carbon dioxide gas permeability coefficient cc · mm / (m ２ ・day・ATM)

[0049]

[0050] In Table 1 above, the units of oxygen barrier property and carbon dioxide gas barrier property are cc mm / (m ２ As is clear from the above results, the molded article (film) formed from the resin composition of the present invention had excellent gas barrier properties compared to a case where no chloride was contained.

Claims

1. Xylylenediamine-based polyamide resin, It comprises at least one chloride selected from the group consisting of alkali metal chlorides and alkaline earth metal chlorides, The resin composition comprising the xylylenediamine-based polyamide resin, wherein 70 mol% or more of the diamine-derived structural units are derived from xylylenediamine, and 70 mol% or more of the diamine-derived structural units are derived from α,ω-linear aliphatic dicarboxylic acids having 4 to 20 carbon atoms.

2. The resin composition according to claim 1, comprising 0.1 to 3 parts by mass of the chloride per 100 parts by mass of the xylylenediamine-based polyamide resin.

3. The resin composition according to claim 1 or 2, wherein the chloride comprises lithium chloride and / or magnesium chloride.

4. The resin composition according to claim 1 or 2, wherein the molar ratio of metaxylylenediamine to paraxylylenediamine in the xylylenediamine is 10 to 100 / 90 to 0 when the total amount of metaxylylenediamine and paraxylylenediamine is 100 moles.

5. The resin composition according to claim 1 or 2, wherein 70 mol% or more of the constituent units derived from the dicarboxylic acid are constituent units derived from one or more of adipic acid, sebacic acid, and dodecanediic acid.

6. The chloride is contained in a proportion of 0.1 to 3 parts by mass per 100 parts by mass of the xylylenediamine-based polyamide resin. The chloride comprises lithium chloride and / or magnesium chloride, The molar ratio of metaxylylenediamine to paraxylylenediamine in the aforementioned xylylenediamine is such that when the total amount of metaxylylenediamine and paraxylylenediamine is 100 moles, the ratio of metaxylylenediamine / paraxylylenediamine is 10 to 100 / 90 to 0. The resin composition according to claim 1, wherein 70 mol% or more of the constituent units derived from the dicarboxylic acid are constituent units derived from one or more of adipic acid, sebacic acid, and dodecanediic acid.

7. A molded article formed from the resin composition according to claim 1, 2, or 6.

8. The molded article according to claim 7, which is an extruded molded article.

9. A molded article according to claim 7, which is a film.

10. A molded article according to claim 9, which is stretched.

11. The molded article according to claim 7, which is an injection-molded article.

12. The molded body according to claim 7, which is a hollow molded body.

13. A multilayer body having the molded body described in claim 7.