Resin composition, single-layer or multilayer film including said resin composition, and method for producing same

Abstract

Embodiments of the present invention relate to a resin composition, a single-layer or multilayer film including the resin composition, and a method for producing the resin composition. The resin composition comprises a propylene-based polymer (A) having a melting point (Tm), as determined with a differential scanning calorimeter (DSC), of 100°C or higher, a styrene-based polymer (B), an olefin-based polymer (C) including a constituent unit derived from an unsaturated carboxylic acid and / or a derivative thereof, and an ethylene-based polymer (D) comprising 60-100 mol% constituent unit derived from ethylene, wherein the content of the styrene-based polymer (B) is 7-48 mass% with respect to 100 mass% of the resin composition.

Description

Resin composition, single-layer or multi-layer film containing the resin composition, and method for producing the same

[0001] One embodiment of the present invention relates to a resin composition capable of producing a single-layer or multi-layer film, or a method for producing the same.

[0002] Polypropylene has traditionally been widely used as a thermoplastic molding material with excellent rigidity, heat resistance, transparency, and other properties. However, because polypropylene is a nonpolar material, it has poor adhesion to polar materials, such as ethylene-vinyl alcohol copolymers. To improve adhesion, a widely known technique involves modifying polypropylene with an unsaturated carboxylic acid or its derivatives. It is also known that the inclusion of a styrene-based elastomer in a polypropylene composition improves water vapor barrier properties. Adhesion and water vapor barrier properties are required for applications such as food packaging, construction materials, and packaging for lithium-ion batteries.

[0003] In recent years, lithium-ion batteries have been increasingly used in portable electronic devices and automobiles. Furthermore, due to the need for greater freedom in shape and miniaturization, the use of pouch-type and embossed exterior packaging made of multilayer film has become widespread. Multilayer film packaging materials used for lithium-ion batteries consist of at least a substrate layer, a metal foil layer, and a thermally adhesive resin layer, as well as an adhesive layer bonding two adjacent layers. Packaging materials for lithium-ion batteries are required to have excellent safety and long-term durability. To maintain the stability of the battery contents, packaging materials must have water vapor barrier properties. Packaging materials are typically formed by deep drawing using a mold at room temperature, and whitening resistance is required during this process. Poor whitening resistance can lead to cracks and pinholes in the stretched areas during forming, resulting in a loss of battery reliability.

[0004] For example, Patent Document 1 discloses that a thermoplastic resin composition containing a styrene-based elastomer and a polypropylene-based resin and a molded article thereof have excellent moisture-proof properties and electrical insulation properties, and therefore can be suitably used as a packaging material for lithium-ion batteries.

[0005] JP 2018-022690 A

[0006] However, polypropylene and styrene-based elastomers generally have poor compatibility, making it difficult to form stable films for packaging. Furthermore, the dispersibility in polyolefin resins varies depending on the styrene content, resulting in significant thickness deviations in the MC and TC directions during film formation, making it necessary to stabilize the morphology within the composition. Furthermore, because the composition contains incompatible components, the interfacial strength of the sea-island phase is weak, making crazes more likely to occur at the interface and resulting in poor whitening resistance.

[0007] One embodiment of the present invention provides a resin composition that provides excellent film formation stability and excellent adhesion, water vapor barrier properties, whitening resistance, and film formation stability for the resulting film; a single-layer or multilayer film containing the resin composition; and a method for producing the same.

[0008] Examples of embodiments of the present invention are given below.

[0009] [1] A resin composition comprising: (A) a propylene polymer (A) having a melting point (Tm) of 100°C or higher as measured by differential scanning calorimetry (DSC), (B) a styrene polymer (B), (C) an olefin polymer containing structural units derived from at least one of an unsaturated carboxylic acid and its derivatives, and (D) an ethylene polymer containing 60 to 100 mol% of structural units derived from ethylene, wherein the content of the styrene polymer (B) is 7 to 48 mass% based on 100 mass% of the resin composition. [2] The resin composition according to item [1], further comprising a propylene-α-olefin copolymer (E). [3] The resin composition according to item [1], further comprising a 1-butene-ethylene copolymer (F), wherein the 1-butene-ethylene copolymer (F) contains 70 to 97 mol% of the structural unit (i) and 3 to 30 mol% of the structural unit (ii), relative to a total of 100 mol% of the structural unit (i) derived from 1-butene and the structural unit (ii) derived from ethylene. [4] The resin composition according to item [2], comprising: 10 to 92.8% by mass of the propylene polymer (A); 7 to 48% by mass of the styrene polymer (B); 0.1 to 10% by mass of the olefin polymer (C); 0.1 to 30% by mass of the ethylene polymer (D); and 0 to 30% by mass of the propylene-α-olefin copolymer (E), where the total of the propylene polymer (A), the styrene polymer (B), the olefin polymer (C), the ethylene polymer (D), and the propylene-α-olefin copolymer (E) is 100% by mass. [5] The resin composition according to item [3], comprising: 10 to 92.8% by mass of the propylene polymer (A); 7 to 48% by mass of the styrene polymer (B); 0.1 to 10% by mass of the olefin polymer (C); 0.1 to 30% by mass of the ethylene polymer (D); and 0 to 30% by mass of the 1-butene-ethylene copolymer (F) (wherein the total of the propylene polymer (A), the styrene polymer (B), the olefin polymer (C), the ethylene polymer (D), and the 1-butene-ethylene copolymer (F) is 100% by mass).[6] The resin composition according to any one of items [1] to [5], wherein the content of structural units derived from at least one of an unsaturated carboxylic acid and its derivative in the olefin polymer (C) is 0.01 to 5 mass% in terms of structural units derived from maleic anhydride, relative to 100 mass% of the olefin polymer (C), and the content of structural units derived from propylene in the olefin polymer (C) is 90 to 100 mol% relative to 100 mol% of structural units excluding structural units derived from at least one of the unsaturated carboxylic acid and its derivative. [7] The resin composition according to any one of items [1] to [6], wherein the ethylene polymer (D) is high-pressure low-density polyethylene (D1). [8] The resin composition according to any one of items [1] to [7], wherein the content of structural units derived from styrene in the styrene polymer (B) is 10 to 40 mass%. [9] A single-layer or multilayer film comprising at least one layer containing the resin composition according to any one of items [1] to [8].

[10] A multilayer film comprising at least one layer containing the resin composition according to any one of items [1] to [8], wherein both sides of the layer containing the resin composition are in contact with other layers.

[11] A multilayer film comprising at least one layer containing the resin composition according to any one of items [1] to [8], wherein one or both sides of the layer containing the resin composition are in contact with at least one of a metal-containing layer, a polyolefin layer, and a polar resin layer.

[12] The monolayer or multilayer film according to any one of items [9] to

[11] , wherein the monolayer or multilayer film is a food packaging film.

[13] The monolayer or multilayer film according to any one of items [9] to

[11] , wherein the monolayer or multilayer film is a building material film.

[14] The monolayer or multilayer film according to any one of items [9] to

[11] , wherein the monolayer or multilayer film is a battery packaging film.

[15] A method for producing a monolayer or multilayer film, comprising a step of melt-extrusion molding the resin composition according to any one of items [1] to [8].

[0010] It is possible to provide a resin composition that is excellent in adhesiveness, water vapor barrier properties, whitening resistance, and film formation stability.

[0011]

[0033] An embodiment of the present invention will be described in detail below. <Resin Composition> From the viewpoint of achieving an excellent balance between adhesiveness, water vapor barrier properties, whitening resistance, and film formation stability, the resin composition according to one embodiment of the present invention contains a propylene polymer (A), a styrene polymer (B), an olefin polymer (C), and an ethylene polymer (D), and may further contain at least one selected from a propylene-α-olefin copolymer (E) and a 1-butene-ethylene copolymer (F).

[0012] A resin composition according to an embodiment of the present invention preferably contains 10 to 92.8% by mass of the propylene polymer (A), 7 to 48% by mass of the styrene polymer (B), 0.1 to 10% by mass of the olefin polymer (C), 0.1 to 30% by mass of the ethylene polymer (D), and 0 to 30% by mass of the propylene-α-olefin copolymer (E) or the 1-butene-ethylene copolymer (F). The total of the propylene polymer (A), the styrene polymer (B), the olefin polymer (C), the ethylene polymer (D), and the propylene-α-olefin copolymer (E) or the 1-butene-ethylene copolymer (F) is taken as 100% by mass. The content of the propylene polymer (A) is more preferably 15 to 90% by mass, and even more preferably 20 to 85% by mass. The content of the styrene polymer (B) is more preferably 7 to 40% by mass, and even more preferably 8 to 35% by mass. The olefin polymer (C) is more preferably 0.5 to 8% by mass, and even more preferably 1 to 7.5% by mass. The ethylene polymer (D) is more preferably 1 to 15% by mass, and even more preferably 3 to 10% by mass. The propylene / α-olefin copolymer (E) is more preferably 5 to 30% by mass, and even more preferably 10 to 30% by mass. The 1-butene / ethylene copolymer (F) is more preferably 5 to 30% by mass, and even more preferably 10 to 25% by mass.

[0013] <Propylene-Based Polymer (A)> The propylene-based polymer (A) (hereinafter also referred to as "polymer (A)") is not particularly limited, and may be a homopolymer of propylene or a copolymer of propylene and an α-olefin other than propylene.

[0014] From the viewpoint of achieving excellent adhesiveness and water vapor barrier properties in the resulting film, the propylene polymer (A) is preferably a copolymer of propylene and an α-olefin other than propylene having 2 to 20 carbon atoms. The copolymer of propylene and an α-olefin other than propylene having 2 to 20 carbon atoms may be a random copolymer or a block copolymer. The propylene polymer (A) may have at least one structural unit derived from a biomass-derived monomer. Examples of biomass-derived monomers include biomass-derived propylene, biomass-derived ethylene, and biomass-derived α-olefins having 4 to 20 carbon atoms. The same type of monomer constituting the polymer may be only biomass-derived monomers, only fossil fuel-derived monomers, or both biomass-derived monomers and fossil fuel-derived monomers.

[0015] Examples of the α-olefins other than propylene having 2 to 20 carbon atoms include ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc. Among these, the α-olefins other than propylene having 2 to 20 carbon atoms are preferably ethylene and α-olefins having 4 to 10 carbon atoms, and more preferably ethylene.

[0016] The upper limit of the structural units derived from an α-olefin other than propylene having 2 to 20 carbon atoms is preferably 35 mol% or less, more preferably 30 mol% or less, even more preferably 20 mol% or less, particularly preferably 10 mol% or less, and most preferably 5 mol% or less, relative to 100 mol% of the copolymer of propylene and an α-olefin other than propylene having 2 to 20 carbon atoms. There is no particular restriction on the lower limit, but it is preferably 0.1 mol% or more, more preferably 0.5 mol% or more, and even more preferably 1 mol% or more.

[0017] The propylene polymer (A) may have an isotactic structure or a syndiotactic structure, and it is preferable to select either structure in consideration of compatibility with the cyclic olefin polymer (B) described later. That is, examples of the form of the propylene polymer (A) include an isotactic propylene polymer (A1) and a syndiotactic propylene polymer (A2).

[0018] <<Isotactic Propylene Polymer (A1)>> Examples of the isotactic propylene polymer (A1) include homopolypropylenes having excellent heat resistance, such as known homopolypropylenes typically containing 3 mol % or less of a copolymerization component other than propylene, block polypropylenes having an excellent balance between heat resistance and flexibility, such as known block polypropylenes typically containing 3 to 30 mass % of a normal decane-eluted rubber component, and random polypropylenes having an excellent balance between flexibility and transparency, such as known random polypropylenes having a melting peak measured by differential scanning calorimetry (DSC) of 100° C. or higher, preferably in the range of 110° C. to 150° C. The isotactic propylene polymer (A1) can be appropriately selected from these to obtain the desired physical properties, or two or more of the polypropylene components having different melting points or rigidities can be used in combination.

[0019] The isotactic propylene polymer (A1) can be produced, for example, by polymerizing propylene or copolymerizing propylene with another α-olefin using a Ziegler catalyst system comprising a solid catalyst component containing magnesium, titanium, a halogen, and an electron donor as essential components, an organoaluminum compound, and an electron donor, or a metallocene catalyst system using a metallocene compound as one of the catalyst components.

[0020] <<Syndiotactic Propylene Polymer (A2)>> The syndiotactic propylene polymer (A2) preferably contains 90 mol % or more of structural units derived from propylene and 10 mol % or less of structural units derived from at least one α-olefin other than propylene having 2 to 20 carbon atoms, and more preferably contains 91 mol % or more of structural units derived from propylene and 9 mol % or less of structural units derived from at least one α-olefin other than propylene having 2 to 20 carbon atoms, provided that the total of the structural units derived from propylene and the structural units derived from at least one α-olefin other than propylene having 2 to 20 carbon atoms is 100 mol %.

[0021] The α-olefin other than propylene having 4 to 20 carbon atoms in the syndiotactic propylene polymer (A2) has the same meaning as the above-mentioned α-olefin other than propylene having 4 to 20 carbon atoms, and preferred embodiments are also the same. The method for producing the syndiotactic propylene polymer (A2) is not particularly limited, and any known production method can be used, and examples thereof include the production method described in WO 2011 / 078054.

[0022] The propylene polymer (A) is preferably an isotactic propylene polymer (A1) from the viewpoint that the resulting film will have excellent adhesiveness and water vapor barrier properties.

[0023] The propylene polymer (A) has a melting point (Tm) of 100° C. or higher as measured by a differential scanning calorimeter (DSC). From the viewpoint of excellent adhesiveness and water vapor barrier property of the resulting film, the melting point (Tm) is preferably 100 to 170° C., more preferably 120 to 165° C., and even more preferably 130 to 150° C. The melting point (Tm) is determined by the measurement method described in the examples below.

[0024] The propylene polymer (A) has a melt flow rate (MFR) measured in accordance with ASTM D1238 at 230°C under a load of 2.16 kg, which is preferably in the range of 0.01 to 1000 g / 10 min, more preferably 0.05 to 50 g / 10 min, still more preferably 0.1 to 20 g / 10 min, and particularly preferably 1 to 10 g / 10 min.

[0025] In the resin composition according to one embodiment of the present invention, the propylene polymer (A) may be used singly or in combination of two or more. From the viewpoint of providing a film with excellent adhesiveness and water vapor barrier properties, the content of the propylene polymer (A) is preferably 10 to 92.8% by mass, more preferably 15 to 90% by mass, and even more preferably 20 to 85% by mass, relative to 100% by mass of the resin composition.

[0026] <Styrene-Based Polymer (B)> The styrene-based polymer (B) (hereinafter also referred to as "polymer (B)") may be a homopolymer of an aromatic vinyl monomer or a copolymer of an aromatic vinyl monomer and a conjugated diene monomer. The styrene-based polymer (B) may be unmodified or modified. From the viewpoint of achieving superior water vapor barrier properties and adhesive properties, the styrene-based polymer (B) is preferably a copolymer containing at least one aromatic vinyl monomer unit and at least one conjugated diene monomer unit, and more preferably a copolymer comprising at least one of a block copolymer containing at least one aromatic vinyl monomer unit and at least one conjugated diene monomer unit, and a hydrogenated product (hydrogenated block copolymer) of a block copolymer containing at least one aromatic vinyl monomer unit and at least one conjugated diene monomer unit. The block copolymer preferably has an aromatic vinyl polymer block unit composed of the aromatic vinyl monomer unit and a conjugated diene polymer block unit composed of the conjugated diene monomer unit. The styrene-based polymer (B) having the aromatic vinyl polymer block unit and the conjugated diene polymer block unit will hereinafter also be referred to as a "styrene-based block copolymer."

[0027] The hydrogenated block copolymer (hydrogenated block copolymer) containing at least one aromatic vinyl monomer unit and at least one conjugated diene monomer unit preferably has a hydrogenated aromatic vinyl polymer block unit composed of the aromatic vinyl monomer unit and a hydrogenated conjugated diene polymer block unit composed of the conjugated diene monomer unit. Hereinafter, the styrenic polymer (B) containing the hydrogenated block copolymer will also be referred to as a "hydrogenated styrenic block copolymer."

[0028] The aromatic vinyl monomer is preferably styrene or a styrene derivative such as α-methylstyrene, more preferably styrene, and the conjugated diene monomer is preferably butadiene or isoprene, more preferably butadiene.

[0029] The relationship between the two block units of the styrene-based block copolymer and the hydrogenated styrene-based block copolymer can be represented by the following formula (1) or formula (2): S-(C-S)m (1) (S)n (2) (In formulas (1) and (2), S represents a polymer block composed of aromatic vinyl monomer units, C represents a polymer block composed of conjugated diene monomer units or a hydrogenated product thereof, and m and n represent integers of 1 to 5.)

[0030] In the hydrogenated block copolymer represented by formula (1), when the polymer block represented by C is composed only of a hydrogenated product (hydrogenated product) of a polybutadiene block unit, it is preferable that the proportion of 1,2-addition structures in the microstructure of the polymer block represented by C is 20 to 70 mass % in order to maintain the properties of an elastomer after hydrogenation.

[0031] In formula (1) and formula (2), larger m and n are preferred from the viewpoint of lowering the order-disorder transition temperature, but smaller m and n are preferred from the viewpoint of ease of production and cost. As the styrene-based polymer (B), a block copolymer or hydrogenated block copolymer represented by formula (1) is preferred from the viewpoint of excellent rubber elasticity, a block copolymer or hydrogenated block copolymer represented by formula (1) in which m is 3 or less is more preferred, and a block copolymer or hydrogenated block copolymer represented by formula (1) in which m is 2 or less is even more preferred.

[0032] The styrene-based polymer (B) is preferably the hydrogenated styrene-based block copolymer. The styrene-based block copolymer and the hydrogenated styrene-based block copolymer may be linear, branched, and / or radial.

[0033] The styrene-based block copolymer is preferably a styrene / butadiene copolymer rubber or a styrene / isoprene copolymer rubber. The hydrogenated styrene-based block copolymer is preferably a styrene / butadiene copolymer rubber or a styrene / isoprene copolymer rubber in which the polybutadiene block unit and / or the polyisoprene block unit has been hydrogenated.

[0034] Examples of the styrene polymer (B) include block copolymers (SBC) with conjugated diene monomer blocks such as isoprene or butadiene, hydrogenated styrene-butadiene-styrene block copolymers (HSBR), styrene-ethylene-propylene-styrene block copolymers (SEPS), styrene-ethylene-butene-styrene block copolymers (SEBS), styrene-isoprene-styrene block copolymers (SIS), styrene-butadiene-styrene copolymers (SBS), styrene-isobutylene-styrene copolymers (SIBS), styrene-isobutylene copolymers (SIB), styrene-isoprene-butadiene-styrene block copolymers, styrene block copolymers (SIS), hydrogenated copolymers of styrene / styrene-butadiene random copolymer / styrene block copolymers (SESS), etc. Among these, the styrene polymer (B) is preferably styrene-ethylene-butene-styrene block copolymers (SEBS), styrene-isobutylene-styrene copolymers (SIBS) or styrene-isobutylene copolymers (SIB).

[0035] The styrene-based polymer (B) may be synthesized or may be a commercially available product. Examples of commercially available styrene-ethylene-butene-styrene block copolymers (SEBS) include Tuftec (registered trademark) from Asahi Kasei Corporation and Kraton (registered trademark) from Shell Corporation. Examples of commercially available styrene-isobutylene-styrene copolymers (SIBS) or styrene-isobutylene copolymers (SIB) include Shibstar (registered trademark) from Kaneka Corporation.

[0036] The styrene-based polymer (B) may be used alone or in combination of two or more. The content of the structural unit derived from an aromatic vinyl monomer in the styrene-based polymer (B) may be 5% by mass or more, or 10% by mass or more, and may be 80% by mass or less, 75% by mass or less, or 70% by mass or less, based on 100% by mass of the styrene-based polymer (B). The content of the structural unit derived from styrene in the styrene-based polymer (B) is preferably 10 to 40% by mass, more preferably 10 to 30% by mass, based on 100% by mass of the styrene-based polymer (B).

[0037] The content of the styrene polymer (B) is 7 to 48% by mass, preferably 7 to 40% by mass, more preferably 8 to 35% by mass, and even more preferably 8 to 20% by mass, relative to 100% by mass of the resin composition. When the content of the styrene polymer (B) is within the above range, the resulting film has an excellent balance between adhesiveness and water vapor barrier property.

[0038] The melt flow rate (MFR) of the styrene polymer (B), measured in accordance with ASTM D1238 at 230°C under a load of 2.16 kg, is preferably in the range of 0.1 to 20 g / 10 min, more preferably 0.1 to 10 g / 10 min.

[0039] <Olefin Polymer (C)> The olefin polymer (C) contains a structural unit derived from at least one of an unsaturated carboxylic acid and a derivative thereof. The structural unit derived from at least one of an unsaturated carboxylic acid and a derivative thereof is a structural unit formed by modifying an unmodified polyolefin with at least one of an unsaturated carboxylic acid and a derivative thereof. The method for modifying an unmodified polyolefin with at least one of an unsaturated carboxylic acid and a derivative thereof is not particularly limited, and a known modification method can be used, and a suitable example is the graft modification method described below.

[0040] Examples of unmodified polyolefins include polypropylene (C1), ethylene-propylene-α-olefin copolymer (C2), and ethylene-α-olefin copolymer (C3).

[0041] <<Polypropylene (C1)>> Examples of polypropylene (C1) include propylene homopolymers and propylene-α-olefin copolymers. The α-olefin copolymerized with propylene is not limited, but preferably includes ethylene and α-olefins having 4 to 20 carbon atoms. These α-olefins may be used alone or in combination of two or more types. However, when the α-olefin is ethylene, it is preferred that no α-olefins having 4 or more carbon atoms are contained. Among these, preferred α-olefins are ethylene and α-olefins having 4 to 10 carbon atoms, and more preferably ethylene and α-olefins having 4 to 8 carbon atoms. The content of structural units derived from propylene in the propylene-α-olefin copolymer is preferably 50 mol% or more, more preferably 80 mol% or more, and even more preferably less than 100%, based on the total structural units of the propylene-α-olefin copolymer.

[0042] The intrinsic viscosity [η] of the polypropylene (C1) is preferably 0.1 to 10 dl / g. The intrinsic viscosity [η] of the olefin polymer (C) obtained by modifying such polypropylene (C1) is preferably 0.1 to 6 dl / g. When the intrinsic viscosity [η] is within the above range, a composition excellent in moldability and mechanical strength can be obtained. The method for producing the polypropylene (C1) is not particularly limited, and examples thereof include well-known methods using well-known catalysts such as Ziegler-Natta catalysts and metallocene catalysts.

[0043] The polypropylene (C1) is preferably a crystalline polymer, and in the case of a copolymer, it may be a random copolymer or a block copolymer. Furthermore, the polypropylene (C1) is not particularly limited in terms of stereoregularity or molecular weight, as long as it satisfies moldability and has strength sufficient for use when formed into a molded article. Furthermore, commercially available resins can be used as is as the polypropylene (C1). Examples of polypropylene (C1) include homopolypropylene and propylene-α-olefin random copolymer. Furthermore, the polypropylene (C1) may contain several different isotactic polypropylenes.

[0044] <<Ethylene-Propylene-α-Olefin Copolymer (C2)>> The ethylene-propylene-α-olefin copolymer (C2) is preferably a copolymer of ethylene, propylene, and an α-olefin having 4 or more carbon atoms, and preferably satisfies, for example, the requirements defined in the following (C-1) and (C-2). Requirement (C-1): The copolymer contains 45 to 90 mol % of structural units derived from propylene, 9 to 25 mol % of structural units derived from ethylene, and 1 to 30 mol % of structural units derived from an α-olefin having 4 to 20 carbon atoms. Requirement (C-2): The copolymer has an intrinsic viscosity [η] in decalin at 135°C of 0.1 to 10 dl / g.

[0045] <<Requirement (C-1)>> As the α-olefin in the ethylene-propylene-α-olefin copolymer (C2), an α-olefin having 4 to 10 carbon atoms can be suitably used, and the α-olefin may be used alone or in combination of two or more. With regard to the proportions of the structural units derived from each monomer in the ethylene-propylene-α-olefin copolymer (C2), preferably 50 to 85 mol% of structural units derived from propylene, 10 to 22 mol% of structural units derived from ethylene, and 5 to 28 mol% of structural units derived from the α-olefin, and more preferably 52 to 80 mol% of structural units derived from propylene, 10 to 20 mol% of structural units derived from ethylene, and 10 to 28 mol% of structural units derived from the α-olefin.

[0046] <<Requirement (C-2)>> The intrinsic viscosity [η] in decalin at 135°C is more preferably 0.5 to 8 dl / g, and even more preferably 0.8 to 6 dl / g. The intrinsic viscosity [η] of the olefin polymer (C) obtained by modifying such an ethylene-propylene-α-olefin copolymer (C2) is preferably 0.5 to 8 dl / g, more preferably 0.8 to 6 dl / g. When the intrinsic viscosity [η] is within the above range, a resin composition having an excellent balance between flexibility and mechanical strength and excellent adhesiveness can be obtained.

[0047] The method for producing the ethylene-propylene-α-olefin copolymer (C2) is not particularly limited, and it can be produced by a well-known method using a well-known catalyst such as a Ziegler-Natta catalyst or a metallocene catalyst.

[0048] The ethylene-propylene-α-olefin copolymer (C2) is not particularly limited in terms of its stereoregularity or molecular weight, as long as it satisfies the moldability and has strength sufficient for use when molded into a molded article. Commercially available resins can be used as the ethylene-propylene-α-olefin copolymer (C2) as they are.

[0049] <<Ethylene / α-olefin copolymer (C3)>> The ethylene / α-olefin copolymer (C3) is preferably a copolymer of ethylene and an α-olefin, and preferably satisfies, for example, the following requirements (C-3) and (C-4).

[0050] Requirement (C-3): Contains 50 to 99 mol % of structural units derived from ethylene and 1 to 50 mol % of structural units derived from an α-olefin having 3 to 20 carbon atoms. Requirement (C-4): Has an intrinsic viscosity [η] in decalin at 135°C of 0.1 to 10 dl / g.

[0051] <<Requirement (C-3)>> The α-olefin in the ethylene / α-olefin copolymer (C3) is more preferably an α-olefin having 3 to 10 carbon atoms, and may be used alone or in combination of two or more. With regard to the proportions of the structural units derived from each monomer in the ethylene / α-olefin copolymer (C3), 55 to 98 mol % of structural units derived from ethylene and 2 to 45 mol % of structural units derived from the α-olefin are preferred, and 60 to 95 mol % of structural units derived from ethylene and 5 to 40 mol % of structural units derived from the α-olefin are even more preferred.

[0052] <<Requirement (C-4)>> The intrinsic viscosity [η] in decalin at 135°C is more preferably in the range of 0.5 to 8 dl / g, and even more preferably in the range of 0.8 to 6 dl / g. The intrinsic viscosity [η] of the olefin polymer (C) obtained by modifying such an ethylene / α-olefin copolymer (C3) is preferably 0.5 to 8 dl / g, more preferably 0.8 to 6 dl / g. When the intrinsic viscosity [η] is in the above range, a resin composition can be obtained that has an excellent balance between flexibility and mechanical strength and provides a film with excellent adhesiveness.

[0053] The method for producing the ethylene / α-olefin copolymer (C3) is not particularly limited, and examples thereof include well-known methods using well-known catalysts such as Ziegler-Natta catalysts and metallocene catalysts.

[0054] The ethylene / α-olefin copolymer (C3) has excellent moldability and is not particularly limited in terms of stereoregularity or molecular weight, as long as it has sufficient strength to withstand use when molded into a film or other molded article. Commercially available resins can be used as the ethylene / α-olefin copolymer (C3) as is.

[0055] Examples of unsaturated carboxylic acids and / or derivatives thereof that modify these unmodified polyolefins include unsaturated compounds having one or more carboxylic acid groups per molecule, esters of compounds having carboxylic acid groups with alkyl alcohols, and unsaturated compounds having one or more carboxylic acid anhydride groups per molecule. Examples of groups having unsaturated bonds in unsaturated compounds include ethylenically unsaturated groups, such as vinyl groups, vinylene groups, and unsaturated cyclic hydrocarbon groups. The unsaturated carboxylic acids and / or derivatives thereof can be used alone or in combination of two or more. Among these, unsaturated carboxylic acids and / or derivatives thereof are preferably unsaturated dicarboxylic acids or their acid anhydrides, with maleic acid, nadic acid, or their acid anhydrides being particularly preferred.

[0056] The content of structural units derived from at least one of an unsaturated carboxylic acid and its derivative contained in the olefin polymer (C) (hereinafter also referred to as the "graft amount") is preferably 0.01 to 5 mass%, and more preferably 0.05 to 3.5 mass%, calculated as structural units derived from maleic anhydride, relative to all structural units of the olefin polymer (C). When the amount of structural units derived from the unsaturated carboxylic acid and / or its derivative is within the above range, a resin composition having an excellent balance of moldability and adhesiveness can be obtained.

[0057] In the olefin polymer (C), the content of propylene-derived structural units in the structural units excluding the structural units derived from the unsaturated carboxylic acid and / or its derivative (i.e., structural units derived from unmodified polyolefin) is preferably 90 to 100 mol %, more preferably 95 to 100 mol %. When the content of propylene-derived structural units is within this range, a resin composition with excellent heat resistance can be obtained.

[0058] The method for grafting an unmodified polyolefin with an unsaturated carboxylic acid and / or a derivative thereof is not particularly limited, and any conventionally known graft polymerization method can be used, such as a solution method, a melt-kneading method, etc. For example, there is a method in which an unmodified polyolefin is melted and an unsaturated carboxylic acid and / or a derivative thereof is added thereto for graft reaction, or a method in which a polyolefin is dissolved in a solvent to prepare a solution and an unsaturated carboxylic acid and / or a derivative thereof is added thereto for graft reaction.

[0059] The olefin polymer (C) preferably contains structural units formed by grafting an unsaturated carboxylic acid and / or a derivative thereof onto an unmodified polyolefin, more preferably contains structural units derived from a polypropylene (C1) graft-modified with a carboxylic acid anhydride, and even more preferably contains structural units derived from a homopolypropylene graft-modified with a carboxylic acid anhydride.

[0060] The olefin polymer (C) may be used singly or in combination of two or more. The content of the olefin polymer (C) is preferably 0.1 to 10 mass%, more preferably 0.5 to 8 mass%, and even more preferably 1 to 7.5 mass%, based on 100 mass% of the resin composition.

[0061] <Ethylene-Based Polymer (D)> When the resin composition contains the ethylene-based polymer (D), the resin composition has excellent moldability during molding processing, and the resulting molded product, such as a film, has an excellent balance of adhesiveness and water vapor barrier property.

[0062] The ethylene polymer (D) is not particularly limited and may be a homopolymer of ethylene or a copolymer of ethylene and an α-olefin other than ethylene. The ethylene polymer (D) contains 60 to 100 mol% of structural units derived from ethylene. Specific examples of the ethylene polymer (D) include high-pressure low-density polyethylene (D1) and ethylene-α-olefin copolymer (D2). From the viewpoint of providing a film with excellent adhesiveness and water vapor barrier properties, the ethylene polymer (D) is preferably high-pressure low-density polyethylene (D1).

[0063] <<High-Pressure Low-Density Polyethylene (D1)>> Known high-pressure low-density polyethylene (D1) can be used without restriction. High-pressure low-density polyethylene is generally polyethylene obtained by radical polymerization of ethylene under high temperature and high pressure. The method for producing high-pressure low-density polyethylene (D1) is not particularly limited, but examples include a radical polymerization method in which radical polymerization is carried out under conditions of 500 to 2000 atmospheres and 150 to 300°C. Examples of polymerization initiators used in radical polymerization include organic peroxides.

[0064] The high-pressure low-density polyethylene (D1) preferably has a density of 0.900 to 0.925 g / cm3 measured in accordance with ASTM D1505. ３ , more preferably 0.910 to 0.925 g / cm ３The density of the high-pressure low-density polyethylene (D1) was measured by a density gradient tube method using a sample obtained by heat-treating a strand obtained during the MFR measurement of the high-pressure low-density polyethylene (D1) at 120°C for 1 hour and slowly cooling it to room temperature over 1 hour.

[0065] The melt flow rate (MFR) of the high-pressure low-density polyethylene (D1), measured in accordance with ASTM D1238 under conditions of 190°C and a load of 2.16 kg, preferably has a lower limit of 0.1 g / 10 min or more, more preferably 0.5 g / 10 min or more, and particularly preferably 1.0 g / 10 min or more, and an upper limit of preferably 50 g / 10 min or less, more preferably 30 g / 10 min or less, and particularly preferably 20 g / 10 min or less.

[0066] <<Ethylene / α-olefin copolymer (D2)>> The ethylene / α-olefin copolymer (D2) preferably contains structural units derived from ethylene and structural units derived from an α-olefin having 3 to 20 carbon atoms.

[0067] The content of structural units derived from ethylene in the ethylene / α-olefin copolymer (D2) is preferably 50 mol% or more, preferably 60 to 99 mol%, more preferably 65 to 99 mol%, even more preferably 70 to 99 mol%, and particularly preferably 80 to 99 mol%, based on all structural units of the copolymer (D2).

[0068] The ethylene / α-olefin copolymer (D2) has fewer long-chain branched structures than the high-pressure low-density polyethylene (D1), and is generally sometimes referred to as linear low-density polyethylene (LLDPD).

[0069] Examples of the α-olefins having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-nonadecene, and 1-eicosene. Among these, the α-olefins having 3 to 20 carbon atoms are preferably α-olefins having 3 to 10 carbon atoms, more preferably α-olefins having 3 to 8 carbon atoms, further preferably propylene, 1-butene, and 1-octene, and particularly preferably propylene.

[0070] The content of structural units derived from an α-olefin having 3 to 20 carbon atoms in the ethylene / α-olefin copolymer (D2) is preferably less than 50 mol %, more preferably 1 to 40 mol %, even more preferably 1 to 35 mol %, particularly preferably 1 to 30 mol %, and most preferably 1 to 20 mol %, based on all structural units in the copolymer (D2). One or more types of α-olefins having 3 to 20 carbon atoms may be used.

[0071] When the content of the structural units derived from ethylene and the structural units derived from an α-olefin having 3 to 20 carbon atoms is within the above range, a molded article such as a film that has excellent moldability during molding processing and a well-balanced excellent adhesion and water vapor barrier property can be easily obtained from the resulting resin composition.

[0072] In addition to the above-mentioned structural units, the ethylene / α-olefin copolymer (D2) may contain one or more structural units derived from polymerizable monomers other than ethylene and α-olefins having 3 to 20 carbon atoms, within the scope of the present invention.

[0073] Examples of such other polymerizable monomers include vinyl compounds such as styrene, vinylcyclopentene, vinylcyclohexane, and vinylnorbornane; vinyl esters such as vinyl acetate; unsaturated organic acids or derivatives thereof such as maleic anhydride; and non-conjugated polyenes such as dicyclopentadiene, cyclohexadiene, and 5-ethylidene-2-norbornene. The content of structural units derived from other polymerizable monomers is preferably 5 mol % or less, more preferably 3 mol % or less, and even more preferably 1 mol % or less, based on the total structural units of the copolymer (D2).

[0074] Specific examples of the ethylene / α-olefin copolymer (D2) include an ethylene / propylene copolymer, an ethylene / 1-butene copolymer, an ethylene / propylene / 1-butene copolymer, an ethylene / propylene / ethylidenenorbornene copolymer, an ethylene / 1-butene / 1-octene copolymer, an ethylene / 4-methyl-1-pentene copolymer, an ethylene / 1-hexene copolymer, and an ethylene / 1-octene copolymer. Among these, from the viewpoint of excellent barrier properties and adhesiveness, the ethylene / α-olefin copolymer (D2) is preferably an ethylene / propylene copolymer or an ethylene / 1-butene copolymer.

[0075] The density of the ethylene / α-olefin copolymer (D2) is preferably 840 kg / m ３ More preferably, 850 kg / m ３ More preferably, 855 kg / m ３ or more, preferably 940 kg / m ３ or less, more preferably 899 kg / m ３ More preferably, 890 kg / m or less ３ Particularly preferably 885 kg / m or less ３ The following is the result.

[0076] When the density is within the above range, a molded article having a good balance of impact resistance, rigidity, and transparency can be easily obtained. The density can be measured by the density gradient tube method described in the Examples.

[0077] The melt flow rate (MFR) of the ethylene / α-olefin copolymer (D2), measured in accordance with ASTM D1238 at 190°C under a load of 2.16 kg, is preferably 0.01 g / 10 min or more, more preferably 0.1 g / 10 min or more, and is preferably 40 g / 10 min or less, more preferably 20 g / 10 min or less, and particularly preferably 10 g / 10 min or less. When the MFR of the copolymer (D2) is within the above range, a molded article having a good balance of excellent impact resistance, rigidity, and transparency can be easily obtained.

[0078] The ethylene / α-olefin copolymer (D2) has an MFR measured at 190°C under a load of 10 kg in accordance with ASTM D1238. １０ and MFR measured under the conditions of 190°C and a load of 2.16 kg. ２．１６ Ratio of MFR １０ / MFR ２．１６ ) is preferably 4.0 or more, more preferably 5.0 or more, and is preferably 8.0 or less, more preferably 7.0 or less. １０ / MFR ２．１６ When the viscosity is within the above range, a molded article having a good balance of transparency and impact resistance can be easily obtained.

[0079] The ethylene / α-olefin copolymer (D2) can be produced by a conventionally known method using a vanadium catalyst, a titanium catalyst, a metallocene catalyst, etc. Preferably, a metallocene catalyst is used for production, which allows for the production of a copolymer having a narrow molecular weight distribution and composition distribution, and is more suitable in terms of mechanical properties, transparency, and impact resistance.

[0080] In the resin composition according to one embodiment of the present invention, the ethylene polymer (D) may be used singly or in combination of two or more. From the viewpoint of excellent barrier properties and adhesiveness, the content of the ethylene polymer (D) is preferably 1 to 15% by mass, more preferably 3 to 10% by mass, relative to 100% by mass of the resin composition.

[0081] <Propylene / α-olefin copolymer (E)> In the propylene / α-olefin copolymer (E) (hereinafter also referred to as "copolymer (E)"), the α-olefin copolymerized with propylene is not limited, but preferably includes ethylene and α-olefins having 4 to 20 carbon atoms, and these α-olefins may be used alone or in combination of two or more. Among these, preferred α-olefins are ethylene and α-olefins having 4 to 10 carbon atoms, and more preferably ethylene and α-olefins having 4 to 8 carbon atoms. From the viewpoint of excellent whitening resistance and water vapor barrier properties, the content of copolymer (E) is preferably 1 to 30 mass%, more preferably 5 to 30 mass%, and more preferably 10 to 30 mass%, relative to 100 mass% of the resin composition.

[0082] <<Propylene-Ethylene-α-Olefin Copolymer (E1)>> The resin composition may further contain a propylene-ethylene-α-olefin copolymer (E1) (hereinafter also referred to as "copolymer (E1)"). When the resin composition contains copolymer (E1), the strength of the sea-island phase interface in the composition is improved, and the resulting film has excellent whitening resistance and water vapor barrier properties. The propylene-ethylene-α-olefin copolymer (E1) preferably satisfies the following requirements (E-1) and (E-2). Requirement (E-1): The copolymer contains 45 to 90 mol % of propylene-derived structural units, 10 to 25 mol % of ethylene-derived structural units, and 1 to 30 mol % of C α-olefin-derived structural units. Requirement (E-2): The intrinsic viscosity [η] in decalin at 135°C is 0.1 to 10 dl / g.

[0083] As the α-olefin in the copolymer (E1), an α-olefin having 4 to 10 carbon atoms can be suitably used, and these may be used alone or in combination of two or more. Examples of the α-olefin having 4 to 10 carbon atoms include 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-nonene, and 1-decene. Among these, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, and 4-methyl-1-pentene are preferred, and 1-butene, 1-hexene, and 4-methyl-1-pentene are more preferred.

[0084] <<Requirement (E-1)>> The proportions of the structural units derived from each monomer contained in the copolymer (E1) are preferably 50 to 85 mol % of structural units derived from propylene, 10 to 22 mol % of structural units derived from ethylene, and 5 to 28 mol % of structural units derived from α-olefin, and more preferably 55 to 80 mol % of structural units derived from propylene, 10 to 20 mol % of structural units derived from ethylene, and 10 to 28 mol % of structural units derived from α-olefin.

[0085] <<Requirement (E-2)>> The intrinsic viscosity [η] is more preferably in the range of 0.5 to 8 dL / g, and even more preferably in the range of 0.8 to 6 dL / g. When the intrinsic viscosity [η] is in this range, an adhesive having an excellent balance between flexibility and mechanical strength and high adhesive strength can be obtained.

[0086] From the viewpoint of providing a film with excellent water vapor barrier properties and adhesiveness, the content of copolymer (E1) is preferably 5 to 30 mass%, more preferably 10 to 30 mass%, based on 100 mass% of the resin composition. One type of copolymer (E1) may be used alone, or two or more types may be used in combination.

[0087] The method for producing the propylene-ethylene-α-olefin copolymer (E1) is not particularly limited, and it can be produced by a known method using a known catalyst such as a Ziegler-Natta catalyst or a metallocene catalyst.

[0088] The propylene-ethylene-α-olefin copolymer (E1) is not particularly limited in terms of its stereoregularity or molecular weight, as long as it satisfies moldability and has sufficient strength to withstand use when molded into a molded product. Commercially available resins can also be used as they are.

[0089] <1-butene / α-olefin copolymer (F)> The 1-butene / ethylene copolymer (F) satisfies the following requirement (F-1). Requirement (F-1) When the total of the structural unit (i) derived from 1-butene and the structural unit (ii) derived from ethylene is taken as 100 mol %, the content of the structural unit (i) is in the range of 70 to 97 mol %, and the content of the structural unit (ii) is in the range of 3 to 30 mol %. From the viewpoint of excellent whitening resistance and water vapor barrier properties, the content of the 1-butene / α-olefin copolymer (F) is preferably 1 to 30 mass %, more preferably 5 to 30 mass %, and more preferably 10 to 30 mass %, relative to 100 mass % of the resin composition.

[0090] Furthermore, the 1-butene / ethylene copolymer (F) preferably satisfies at least one of the following requirements (F-2) to (F-4): Requirement (F-2) １3 The isotactic pendant fraction (mmmm) calculated by C-NMR is in the range of 80 to 99.9%. Requirement (F-3) The intrinsic viscosity [η] in decalin solvent at 135°C is in the range of 0.7 to 2.5 dl / g. Requirement (F-4) The melt flow rate (MFR) measured in accordance with ASTM D1238 at 190°C under a load of 2.16 kg is in the range of 1 to 100 g / 10 min.

[0091] These requirements for the 1-butene / ethylene copolymer (F) will be explained in detail below.

[0092] <<Requirement (F-1)>> When the total of the structural units (i) derived from 1-butene and the structural units (ii) derived from ethylene is taken as 100 mol%, the content of the structural units (i) is in the range of 70 to 97 mol%, and the content of the structural units (ii) is in the range of 3 to 30 mol%. In the 1-butene-ethylene copolymer (F), the lower limit for the amount of structural units derived from 1-butene is 70 mol%. The lower limit for these structural units is preferably 75 mol%, more preferably 80 mol%, even more preferably 83 mol%, and particularly preferably 85 mol%.

[0093] On the other hand, the upper limit of the amount of structural units derived from 1-butene is 97 mol%, preferably 96 mol%, more preferably 95 mol%, even more preferably 94 mol%, and particularly preferably 90.5 mol%.

[0094] In the 1-butene / ethylene copolymer (F), the upper limit of the amount of the structural unit (ii) derived from ethylene is 30 mol %, preferably 25 mol %, more preferably 20 mol %, even more preferably 17 mol %, and particularly preferably 15 mol %.

[0095] On the other hand, the lower limit of the amount of the structural unit (ii) derived from ethylene is 3 mol%, preferably 4 mol%, more preferably 5 mol%, even more preferably 6 mol%, and particularly preferably 9.5 mol%.

[0096] By adjusting the amount of the structural unit (ii) derived from ethylene in the 1-butene-ethylene copolymer (F) to fall within the above range, good compatibility with the propylene polymer (A) can be achieved. When the amount of the structural unit derived from ethylene is equal to or less than the upper limit, the copolymer exhibits excellent mechanical strength, and when used as a packaging material, for example, the copolymer exhibits excellent adhesive strength and improved film durability, which is preferable. When the amount is equal to or greater than the lower limit, the copolymer exhibits an appropriate crystallization rate, which is preferable because, for example, the copolymer exhibits a wider range of molding conditions during molding and improved moldability, and when used as a packaging material, the copolymer exhibits excellent whitening resistance during stretching or deformation processing when combined with the propylene polymer (A).

[0097] The content (mol %) of each structural unit constituting the 1-butene / ethylene copolymer (F) is: １3 The measurement is carried out by C-NMR, and the details of the measurement method are as described in the Examples below.

[0098] <<Requirements (F-2)>> １3 The isotactic pentad fraction (mmmm) calculated by C-NMR is in the range of 80 to 99.9%. The lower limit of the isotactic pentad fraction (mmmm) of the 1-butene / ethylene copolymer (F) according to the present invention is preferably 85%, more preferably 90%. The upper limit of the isotactic pentad fraction (mmmm) is preferably 99.5%, more preferably 99.0%. By controlling the isotactic pentad fraction (mmmm) within the above range, it becomes possible to design the copolymer with appropriate mechanical strength and flexibility, even when ethylene is copolymerized and the compatibility with the propylene-based copolymer (E2) described below is controlled. Details of the method for measuring the isotactic pentad fraction (mmmm) are as described in the Examples below.

[0099] <<Requirement (F-3)>> The intrinsic viscosity [η] in decalin solvent at 135°C is 0.7 to 2.5 dl / g. The intrinsic viscosity [η] of the 1-butene / ethylene copolymer (F) according to the present invention is more preferably 0.8 to 2.3 dl / g, even more preferably 0.9 to 2.25 dl / g, and particularly preferably 1.0 to 2.2 dl / g. A 1-butene / ethylene copolymer (F) having an intrinsic viscosity [η] within the above range has an excellent balance between fluidity and mechanical strength. For example, by containing the 1-butene / ethylene copolymer (F), a molded product having excellent mechanical properties can be easily obtained, and this is preferable because it allows for both ease of molding and durability of the packaging material.

[0100] <<Requirement (F-4)>> The melt flow rate (MFR) measured in accordance with ASTM D1238 at 190°C under a load of 2.16 kg is in the range of 1 to 100 g / 10 min. The MFR of the 1-butene / ethylene copolymer (F) is preferably 1 to 50 g / 10 min, more preferably 1 to 30 g / 10 min, even more preferably 1 to 10 g / 10 min, and particularly preferably 2 to 8 g / 10 min. When the MFR of the 1-butene / ethylene copolymer (F) is in the above range, the flowability is good, and the obtained molded article has good mechanical properties.

[0101] When the MFR is equal to or higher than the lower limit, the composition containing the 1-butene / ethylene copolymer (F) has fluidity and is suitable for high-speed molding, whereas when the MFR is equal to or lower than the upper limit, the composition containing the 1-butene / ethylene copolymer (F) is excellent in mechanical properties, adhesive strength, and durability, which is preferable.

[0102] The 1-butene-ethylene copolymer (F) may be partially graft-modified with a polar monomer. Examples of the polar monomer include hydroxyl group-containing ethylenically unsaturated compounds, amino group-containing ethylenically unsaturated compounds, epoxy group-containing ethylenically unsaturated compounds, aromatic vinyl compounds, unsaturated carboxylic acids or derivatives thereof, vinyl ester compounds, and vinyl chloride. The modified 1-butene-ethylene copolymer (F) can be obtained by graft polymerizing a polar monomer onto the 1-butene-ethylene copolymer (F) described above. When graft polymerizing the polar monomer onto the 1-butene-ethylene copolymer (F), the polar monomer is typically used in an amount of 1 to 100 parts by mass, preferably 5 to 80 parts by mass, per 100 parts by mass of the 1-butene-ethylene copolymer (F). This graft polymerization is typically carried out in the presence of a radical initiator. Examples of the radical initiator that can be used include organic peroxides and azo compounds. The radical initiator can be used by directly mixing with the 1-butene-ethylene copolymer (F) and the polar monomer, or can be used after dissolving in a small amount of organic solvent. Any organic solvent can be used as this organic solvent, as long as it can dissolve the radical initiator. Furthermore, a reducing substance may be used when graft polymerizing the polar monomer onto the 1-butene-ethylene copolymer (F). The use of a reducing substance can increase the amount of polar monomer grafted.

[0103] The graft modification of the 1-butene-ethylene copolymer (F) with a polar monomer can be carried out by a conventionally known method. For example, the 1-butene-ethylene copolymer (F) can be dissolved in an organic solvent, followed by adding a polar monomer and a radical initiator to the solution, and reacting the mixture at a temperature of 70 to 200°C, preferably 80 to 190°C, for 0.5 to 15 hours, preferably 1 to 10 hours. Alternatively, the modified 1-butene-ethylene copolymer (F) can be produced by reacting the 1-butene-ethylene copolymer (F) with the polar monomer without a solvent, using an extruder or the like. This reaction is preferably carried out at a temperature above the melting point of the 1-butene-ethylene copolymer (F), specifically at 120 to 250°C, for typically 0.5 to 10 minutes.

[0104] The modification amount (graft amount of polar monomer) of the modified 1-butene-ethylene copolymer obtained in this manner is usually 0.1 to 50 mass%, preferably 0.2 to 30 mass%, and more preferably 0.2 to 10 mass%. When the propylene-based polymer composition of the present invention contains the modified 1-butene-ethylene copolymer as the 1-butene-ethylene copolymer (F), the propylene-based polymer composition of the present invention may have excellent adhesion and compatibility with other resins and may improve the wettability of the surface of a molded article. The 1-butene-ethylene copolymer (F) may be used alone or in combination of two or more types in the resin composition of the present invention.

[0105] <Other Polymers> The resin composition of the present invention may contain polymers (hereinafter also referred to as "other polymers") other than the propylene polymer (A), styrene polymer (B), olefin polymer (C), ethylene polymer (D), propylene-α-olefin copolymer (E), and 1-butene-ethylene copolymer (F) as long as the effects of the present invention are not impaired. Examples of other polymers include ethylene homopolymers, 1-butene homopolymers, and ethylene-1-pentene random copolymers.

[0106] <Other Components> In addition to the propylene polymer (A), styrene polymer (B), olefin polymer (C), ethylene polymer (D), propylene-α-olefin copolymer (E), and 1-butene-ethylene copolymer (F), the resin composition of the present invention may contain other components other than polymers (hereinafter also referred to as "other components"). Examples of other components include antioxidants, heat stabilizers, weather stabilizers, UV absorbers, neutralizing agents, nucleating agents, light stabilizers, antistatic agents, slip agents, antiblocking agents, crystal nucleating agents, lubricants, odor absorbers, antibacterial agents, moisture absorbers, pigments, and inorganic and organic fillers. The content of these other components is not particularly limited, but is typically 10% by mass or less, preferably 0.01 to 5% by mass, based on 100% by mass of the resin composition.

[0107] <Method for Producing Resin Composition> The method for producing the resin composition according to one embodiment of the present invention is not particularly limited, and may be a conventionally known method, such as a method of melt-kneading the above-mentioned components.

[0108] <Film> The film according to one embodiment of the present invention may be a single-layer film or a multilayer film. When the film according to one embodiment of the present invention is a multilayer film, it has at least one layer containing the resin composition. Examples of uses of the film according to one embodiment of the present invention include food packaging films, construction material films, and battery packaging films.

[0109] A multilayer film according to one embodiment of the present invention includes at least one layer containing a resin composition. For example, both sides of the layer containing the resin composition are in contact with another layer, or one or both sides of the layer containing the composition are in contact with another layer included in the multilayer film. Examples of other layers in contact with the layer containing the composition include a metal-containing layer, a polyolefin layer, and a polar resin layer. Examples of metal-containing layers include an aluminum layer, a copper layer, and a stainless steel layer. Examples of polyolefin layers include a polypropylene layer, a poly(4-methylpentene) layer, and a polyethylene layer. Examples of polar resin layers include a polyamide layer, an EVOH layer, a PET layer, and a PBT layer.

[0110] <Film Manufacturing Method> The monolayer and multilayer films according to one embodiment of the present invention can be obtained by melt extrusion molding, and can be manufactured by a commonly used industrial method such as a casting method, an inflation method, or an extrusion lamination method.

[0111] Hereinafter, one embodiment of the present invention will be described in more detail based on examples, but the present invention is not limited to these examples in any way.

[0112] (Various Measurement Methods) In the examples, measurements were carried out according to the following methods: [Melt Flow Rate (MFR)] Melt flow rate was measured at 230° C. under a load of 2.16 kg in accordance with ASTM D1238.

[0113] [Melting point (Tm)] Measurement was performed using a differential scanning calorimeter (DSC220C, manufactured by Seiko Instruments Inc.) as the measuring device. Approximately 5 mg of sample was sealed in a measurement aluminum pan and heated from room temperature to 230°C at 10°C / min. To completely melt the sample, it was held at 230°C for 10 minutes and then cooled to -40°C at 10°C / min. After leaving it at -40°C for 1 minute, it was heated a second time to 230°C at 10°C / min, and the peak temperature (°C) at this second heating was taken as the melting point (Tm). When multiple peaks were detected, the peak detected on the highest temperature side was used.

[0114] [Water Vapor Barrier Properties] A 40 μm thick film was formed using the resin composition prepared in the Examples or Comparative Examples described below using an extruder equipped with a T-die. The obtained film was subjected to a test in accordance with ASTM F1249 using a PERMATRAN-W3 / 33 manufactured by MOCON Corp. at a test temperature of 40°C, a test humidity of 90% RH, and a test area of ​​50 cm. ２ Under the conditions, the water vapor permeability coefficient (g mm / (m ２ The smaller the water vapor permeability coefficient, the better the water vapor barrier property.

[0115] [Adhesion] A 40 μm thick film was formed using the resin composition prepared in the Examples or Comparative Examples using an extruder equipped with a T-die. A 300 μm thick aluminum foil was placed on one side of the obtained film and heat-sealed for 10 seconds using a heat sealer at 180 ° C and 0.1 MPa to obtain a multilayer film. The obtained multilayer film was cut into 15 mm wide test pieces, and the adhesive strength (N / 15 mm) between the aluminum foil layer and the resin composition layer was measured at room temperature of 23 ° C using a tensile tester using the 180 ° peel method. The higher the adhesive strength value, the better the adhesiveness.

[0116] [Evaluation of Whitening Resistance] A 0.5 mm thick press sheet (single layer film) was prepared using a press molding machine under the following conditions: preheating and pressing temperature 200°C, preheating time 6 minutes, pressure 10 MPa, pressing time 4 minutes, cooling temperature 20°C, cooling time 4 minutes, and pressure 10 MPa. According to JIS K6251, a No. 2 dumbbell was punched out of the press sheet to prepare a test specimen. Using a Shimadzu Corporation ATX tensile tester, the test specimen was stretched at room temperature at a tensile speed of 200 mm / min to 0 mm and 20 mm. The hue change of the test specimen was measured using a Konica Minolta CM-3700A by reflection method. The hue change when stretched 20 mm from the initial value (0 mm) was taken as ΔL. ΔL≦10 was taken as +++, ΔL≦40 was taken as ++, and ΔL>40 was taken as +.

[0117] [Film Formability] A 40 μm thick film was molded using the resin composition prepared in each Example or Comparative Example using an extruder equipped with a T-die. The thickness deviation in the TD and MD of the obtained film was evaluated as follows: - if the thickness deviation was large in both the TD and MD, + if the thickness deviation was observed in the MD, and ++ if the thickness deviation was absent in both the TD and MD.

[0118] (Polyolefins Used) The polyolefins used in the Examples and Comparative Examples are shown below. Unless otherwise specified, all polyolefins were prepared by polymerization according to conventional methods.

[0119] <Propylene Polymer (A)> Hereinafter, PP-1, PP-2, and PP-3 all correspond to isotactic propylene polymers (A1). PP-1: Random polypropylene (propylene content 96 mol%, ethylene content 4 mol%, MFR = 3.0 g / 10 min, Tm = 140°C) PP-2: Random polypropylene (propylene content 96 mol%, ethylene content 4 mol%, MFR = 7.0 g / 10 min, Tm = 138°C) PP-3: Random polypropylene (propylene content 97 mol%, ethylene content 3 mol%, MFR = 2.0 g / 10 min, Tm = 141°C)

[0120] <Styrene-based polymers (B)> St-1: styrene-ethylene-butene-styrene block copolymer (SEBS) (manufactured by Asahi Kasei Corporation, product name: Tuftec SEBS H1041, styrene (St) content = 30 wt%, MFR = 5.0 g / 10 min) St-2: styrene-ethylene-butene-styrene block copolymer (SEBS) (manufactured by Asahi Kasei Corporation, product name: Tuftec SEBS H1221, styrene (St) content = 12 wt%, MFR = 4.5 g / 10 min) St-3: manufactured by Kaneka Corporation, product name: SIBSTER SIBS 073T (styrene (St) content = 30 wt%, MFR = 6.0 g / 10 min) Modified St-4: modified styrene-ethylene-butene-styrene block copolymer (modified SEBS) (manufactured by Asahi Kasei Corporation, product name: Tuftec SEBS M1913, styrene (St) content = 30 wt%, MFR = 5.0 g / 10 min)

[0121] <Olefin Polymer (C)> Modified PP-1: Modified homopolypropylene (maleic anhydride graft amount=3.0 mass%, intrinsic viscosity [η]=0.4 dl / g)

[0122] <Ethylene-based polymer (D)> D-1: high-pressure low-density polyethylene (MFR = 18 g / 10 min, density = 0.92 g / cm ３ )

[0123] <Propylene / α-olefin copolymer (E)> E-1: propylene / ethylene / 1-butene copolymer (16 mol% structural units derived from ethylene, 78 mol% structural units derived from propylene, 6 mol% structural units derived from 1-butene, MFR = 6.0 g / 10 min)

[0124] <1-butene / ethylene copolymer (F)> F-1: 1-butene / ethylene copolymer (88 mol% structural units derived from 1-butene, 12 mol% structural units derived from ethylene, MFR = 6.8 g / 10 min)

[0125] Example 1 21 parts by mass of PP-1, 39 parts by mass of PP-3, 10 parts by mass of St-1, 5 parts by mass of modified PP-1, 5 parts by mass of D-1, and 20 parts by mass of E-1 were melt-kneaded at 230°C using a single-screw extruder to prepare a resin composition.

[0126] [Examples 2 to 16, Comparative Examples 1 to 8, and Reference Examples 1 to 4] In Examples 2 to 16, Comparative Examples 1 to 8, and Reference Examples 1 to 4, resin compositions were prepared in the same manner as in Example 1, except that the compositions were changed to those shown in Table 1.

[0127] Tables 1 to 3 show the MFR of the resin compositions prepared in the Examples, Comparative Examples, and Reference Examples, as well as the film-forming properties, water vapor barrier properties, and whitening resistance of films produced from these resin compositions, and the adhesive strength of multilayer films.

[0128]

[0129]

[0130]

Claims

1. A resin composition comprising: (A) a propylene-based polymer having a melting point of 100°C or higher as measured by a differential scanning calorimeter; (B) a styrene-based polymer; (C) an olefin-based polymer containing structural units derived from at least one of an unsaturated carboxylic acid and a derivative thereof; and (D) an ethylene-based polymer containing 60 to 100 mol% of structural units derived from ethylene, wherein the content of the styrene-based polymer (B) is 7 to 48% by mass relative to 100% by mass of the resin composition.

2. The resin composition according to claim 1, further comprising a propylene-α-olefin copolymer (E).

3. The resin composition according to claim 1, further comprising a 1-butene-ethylene copolymer (F), wherein the 1-butene-ethylene copolymer (F) contains 70 to 97 mol% of structural unit (i) and 3 to 30 mol% of structural unit (ii), relative to 100 mol% in total of structural unit (i) derived from 1-butene and structural unit (ii) derived from ethylene.

4. The resin composition according to claim 2, comprising 10 to 92.8% by mass of the propylene polymer (A), 7 to 48% by mass of the styrene polymer (B), 0.1 to 10% by mass of the olefin polymer (C), 0.1 to 30% by mass of the ethylene polymer (D), and 0 to 30% by mass of the propylene-α-olefin copolymer (E), wherein the total of the propylene polymer (A), the styrene polymer (B), the olefin polymer (C), the ethylene polymer (D), and the propylene-α-olefin copolymer (E) is 100% by mass.

5. The resin composition according to claim 3, comprising 10 to 92.8% by mass of the propylene polymer (A), 7 to 48% by mass of the styrene polymer (B), 0.1 to 10% by mass of the olefin polymer (C), 0.1 to 30% by mass of the ethylene polymer (D), and 0 to 30% by mass of the 1-butene-ethylene copolymer (F), wherein the total of the propylene polymer (A), the styrene polymer (B), the olefin polymer (C), the ethylene polymer (D), and the 1-butene-ethylene copolymer (F) is 100% by mass.

6. The resin composition according to claim 1, wherein the content of structural units derived from at least one of an unsaturated carboxylic acid and a derivative thereof in the olefin polymer (C) is 0.01 to 5 mass% in terms of structural units derived from maleic anhydride relative to 100 mass% of the olefin polymer (C), and the content of structural units derived from propylene in the olefin polymer (C) is 90 to 100 mol% relative to 100 mol% of structural units excluding structural units derived from at least one of the unsaturated carboxylic acid and a derivative thereof.

7. The resin composition according to claim 1, wherein the ethylene polymer (D) is a high-pressure low-density polyethylene (D1).

8. The resin composition according to claim 1, wherein the content of structural units derived from styrene in the styrene-based polymer (B) is 10 to 40% by mass.

9. A single-layer or multi-layer film comprising at least one layer containing the resin composition according to any one of claims 1 to 8.

10. A multilayer film comprising at least one layer containing the resin composition according to any one of claims 1 to 8, with both sides of the layer containing the resin composition being in contact with other layers.

11. A multilayer film comprising at least one layer containing the resin composition according to any one of claims 1 to 8, wherein one or both sides of the layer containing the resin composition are in contact with at least one layer selected from the group consisting of a metal-containing layer, a polyolefin layer, and a polar resin layer.

12. The monolayer or multilayer film according to claim 9, which is a food packaging film.

13. The monolayer or multilayer film according to claim 9, which is a film for construction materials.

14. The monolayer or multilayer film according to claim 9, which is a film for packaging batteries.

15. The monolayer or multilayer film according to claim 10, which is a film for packaging batteries.

16. The monolayer or multilayer film according to claim 11, which is a film for packaging batteries.

17. A method for producing a monolayer or multilayer film, comprising the step of melt-extrusion molding the resin composition according to any one of claims 1 to 8.

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