Composition and molded article

Abstract

To provide a composition that achieves enhanced degradability while maintaining heat sealability, and a molded article obtained from the composition.SOLUTION: A composition comprises a copolymer (A) containing one or more selected from the group consisting of an ethylene-unsaturated ester copolymer (A1) and at least one selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof (A2), and a degradation agent (B) that comprises a plurality of fatty acid metal salts.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a composition and a molded article. [Background technology]

[0002] In recent years, waste plastics have become a problem and are attracting attention as an environmental issue, and there is an increasing demand for biodegradable plastics. Patent documents 1 to 3 include those relating to the degradability of plastics.

[0003] Patent Document 1 discloses a resin molded article that includes a decomposer containing multiple fatty acid metal salts and a resin containing polypropylene, where the multiple metal elements contained in the multiple fatty acid metal salts are metal elements that can have different oxidation numbers from each other, and describes that it is possible to provide a resin molded article with excellent decomposability.

[0004] Patent Document 2 discloses a method for decomposing resin molded bodies, characterized in that the resin molded bodies are decomposed by applying, scattering, spraying, or immersing a decomposition treatment liquid containing a plurality of fatty acid metal salts with different oxidation numbers to the resin molded bodies. The document describes that a method for decomposing resin molded bodies and a decomposable resin product can be provided, which can decompose resin molded bodies made primarily from thermoplastic resin, particularly polyolefin resin, without impairing the mechanical strength, water resistance, and chemical resistance at the time of production and without requiring specific disposal measures.

[0005] Patent Document 3 discloses a decomposition treatment liquid for resin molded bodies that is attached to resin molded bodies by any of coating, sprinkling, atomizing, or immersion when decomposing resin molded bodies whose main raw material is a thermoplastic resin, the decomposition treatment liquid being characterized by containing manganese oleate and cerium oleate. It describes that it is possible to provide a decomposition treatment liquid for resin molded bodies that can decompose resin molded bodies whose main raw material is a thermoplastic resin, in particular a polyolefin resin, without impairing the mechanical strength, water resistance, or chemical resistance at the time of production and without taking any specific disposal means. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2022-076946 [Patent Document 2] International Publication No. 2019 / 207751 [Patent Document 3] Patent Publication No. 2021-008627 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in view of the above circumstances, and provides a composition that maintains heat sealability while improving degradability, and a molded article obtained from the composition. [Means for solving the problem]

[0008] The present inventors have found that a composition having improved degradability while maintaining heat sealability can be obtained by using a copolymer (A) containing one or more members selected from the group consisting of an ethylene-unsaturated ester copolymer (A1) and at least one member (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and its ionomer, and a decomposition agent (B) containing multiple fatty acid metal salts.

[0009] The present invention provides the following composition and molded article.

[0010] [1] A composition comprising a copolymer (A) containing one or more members selected from the group consisting of an ethylene-unsaturated ester copolymer (A1) and at least one member (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and its ionomer, and a decomposing agent (B) containing multiple metal salts of fatty acids. [2] The composition according to [1], wherein the ethylene-unsaturated ester copolymer (A1) comprises one or more copolymers selected from the group consisting of ethylene-vinyl ester copolymers and ethylene-unsaturated carboxylic acid ester copolymers. [3] The composition according to [1] or [2], wherein the at least one member (A2) selected from the group consisting of an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof includes an ethylene-(meth)acrylic acid copolymer. [4] The composition according to any one of [1] to [3], wherein the content of the decomposing agent (B) is 0.02 parts by mass or more and 2 parts by mass or less with respect to 100 parts by mass of the composition. [5] The composition according to any one of [1] to [4], wherein the cracking agent (B) contains petroleum carbonized oil. [6] The composition according to [5], wherein the content of the petroleum carbonized oil is 5 parts by mass or more and 30 parts by mass or less per 100 parts by mass of the cracking agent (B). [7] The composition according to any one of [1] to [6], wherein the plurality of fatty acid metal salts contain a plurality of metal elements, and the oxidation numbers of the plurality of metal elements are different from one another. [8] The composition according to any one of [1] to [7], wherein the plurality of fatty acid metal salts contain a plurality of metal elements, and the plurality of metal elements contain a transition metal element and a rare earth element. [9] The composition according to any one of [1] to [8], wherein the fatty acids forming the plurality of fatty acid metal salts include fatty acids having 12 to 24 carbon atoms.

[10] The composition according to any one of [1] to [9], wherein the plurality of fatty acid metal salts include one or more selected from the group consisting of manganese oleate, cerium oleate, manganese stearate, and cerium stearate.

[11] Further containing a polyolefin resin (C), The composition according to any one of [1] to

[10] , wherein the content of the polyolefin resin (C) is 300 parts by mass or more per 100 parts by mass of the decomposing agent (B).

[12] A molded article obtained from the composition according to any one of [1] to

[11] . [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a composition that maintains heat sealability while improving degradability, and a molded article obtained from the composition. DETAILED DESCRIPTION OF THE INVENTION

[0012] In this specification, "A to B" indicating a range of numerical values ​​means A or more and B or less unless otherwise specified.

[0013] 1. Composition The composition of the present embodiment comprises a copolymer (A) containing one or more copolymers selected from the group consisting of an ethylene-unsaturated ester copolymer (A1) and at least one copolymer (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof, and a decomposing agent (B) containing multiple metal salts of fatty acids.

[0014] According to the composition of the present embodiment, a composition having improved degradability while maintaining heat sealability can be provided by containing a copolymer (A) containing one or more copolymers selected from the group consisting of an ethylene-unsaturated ester copolymer (A1) and at least one copolymer (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof, and a decomposer (B) containing a plurality of fatty acid metal salts. Although the detailed mechanism is unclear, it is thought that the fatty acid metal salt in the decomposition agent (B) causes oxidative decomposition of the copolymer (A) through a catalytic reaction, and that the decomposition ability is improved by energy such as light and heat in the natural environment.

[0015] <Copolymer (A)> The copolymer (A) in the composition of the present embodiment contains, from the viewpoint of improving heat sealability, one or more copolymers selected from the group consisting of ethylene-unsaturated ester copolymers (A1) and at least one copolymer (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof.

[0016] (Ethylene-unsaturated ester copolymer (A1)) The ethylene-unsaturated ester copolymer (A1) is a copolymer of ethylene and at least one unsaturated ester. The ethylene-unsaturated ester copolymer (A1) may be in the form of a block copolymer, a random copolymer, or a graft copolymer. However, in consideration of productivity, it is preferable to use a binary random copolymer, a tertiary random copolymer, a graft copolymer of a binary random copolymer, or a graft copolymer of a tertiary random copolymer, and more preferably a binary random copolymer or a tertiary random copolymer. The ethylene-unsaturated ester copolymer (A1) preferably contains one or more copolymers selected from the group consisting of ethylene-vinyl ester copolymers and ethylene-unsaturated carboxylic acid ester copolymers, and more preferably contains an ethylene-vinyl ester copolymer from the viewpoint of further improving heat sealability. The ethylene-unsaturated ester copolymer (A1) may contain a polymerizable monomer other than ethylene and an unsaturated ester, for example, an α-olefin such as propylene, butene, or hexene.

[0017] The ethylene-vinyl ester copolymer preferably contains one or more selected from the group consisting of ethylene-vinyl acetate copolymer, ethylene-vinyl propionate copolymer, ethylene-vinyl butyrate copolymer, and ethylene-vinyl stearate copolymer, and from the viewpoint of further improving heat sealability, more preferably contains ethylene-vinyl acetate copolymer.

[0018] Ethylene-unsaturated carboxylic acid ester copolymers are copolymers of ethylene and at least one type of unsaturated carboxylic acid ester. Specifically, it can be a copolymer made of ethylene and an unsaturated carboxylic acid alkyl ester.

[0019] As the unsaturated carboxylic acid in the unsaturated carboxylic acid ester, preferably, one or more selected from the group consisting of acrylic acid, methacrylic acid, 2-ethylacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, maleic anhydride, fumaric anhydride, itaconic anhydride, monomethyl maleate, monoethyl maleate, and monoethyl maleate can be used. Among these, the unsaturated carboxylic acid preferably includes at least one selected from the group consisting of acrylic acid and methacrylic acid, from the viewpoint of further improving the productivity and sanitation of the ethylene-unsaturated ester copolymer (A1). These unsaturated carboxylic acids may be used alone or in combination of two or more.

[0020] The alkyl moiety in the unsaturated carboxylic acid alkyl ester may have 1 to 12 carbon atoms, and more specifically, may be exemplified by alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, secondary butyl, 2-ethylhexyl, and isooctyl. Preferably, the alkyl moiety in the alkyl ester has 1 to 8 carbon atoms. Among these, the alkyl moiety preferably contains at least one selected from the group consisting of methyl and ethyl, and more preferably contains methyl.

[0021] The unsaturated carboxylic acid ester is preferably one or more selected from alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-propyl (meth)acrylate, isobutyl (meth)acrylate, n-butyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dimethyl maleate, and diethyl maleate. Among these, it is more preferable to use one or more selected from methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, n-propyl (meth)acrylate, isobutyl (meth)acrylate, and n-butyl (meth)acrylate, and it is even more preferable to use one or two selected from methyl (meth)acrylate and ethyl (meth)acrylate, and it is even more preferable to use methyl (meth)acrylate.

[0022] From the viewpoint of further improving the balance of performances such as mechanical strength, processability, and productivity, the content of structural units derived from ethylene in the ethylene-unsaturated ester copolymer (A1) is preferably from 50% by mass to 99% by mass, more preferably from 60% by mass to 97% by mass, even more preferably from 70% by mass to 95% by mass, and still more preferably from 80% by mass to 92% by mass, when the entire ethylene-unsaturated ester copolymer (A1) is taken as 100% by mass.

[0023] The content of structural units derived from unsaturated esters in the ethylene-unsaturated ester copolymer (A1) is preferably from 1 to 50% by mass, more preferably from 3 to 40% by mass, even more preferably from 5 to 30% by mass, and still more preferably from 8 to 20% by mass, when the entire ethylene-unsaturated ester copolymer (A1) is taken as 100% by mass. When the content of the structural units derived from unsaturated ester in the ethylene-unsaturated ester copolymer (A1) is not less than the above-mentioned lower limit, the heat sealability is further improved, and when the content of the structural units derived from unsaturated ester in the ethylene-unsaturated ester copolymer (A1) is not more than the above-mentioned upper limit, the suitability for extrusion lamination is further improved.

[0024] When the ethylene-unsaturated ester copolymer (A1) is an ethylene-vinyl acetate copolymer, the content of structural units derived from vinyl acetate can be determined in accordance with JIS K7192:1999 by heating the ethylene-vinyl acetate copolymer in an electric furnace to 500°C or higher to decompose it, and then subjecting the resulting acetic acid derived from vinyl acetate to neutralization titration.

[0025] Furthermore, the content of structural units derived from unsaturated esters in the ethylene-unsaturated ester copolymer (A1) relative to the entire composition is preferably from 1 to 50% by mass, more preferably from 3 to 40% by mass, even more preferably from 5 to 30% by mass, and still more preferably from 8 to 20% by mass. When the content of the structural units derived from unsaturated esters in the ethylene-unsaturated ester copolymer (A1) relative to the entire composition is not less than the above-mentioned lower limit, the heat sealability is further improved, and when the content of the structural units derived from unsaturated esters in the ethylene-unsaturated ester copolymer (A1) relative to the entire composition is not more than the above-mentioned upper limit, the suitability for extrusion lamination is further improved.

[0026] The content of the structural units derived from unsaturated esters in the ethylene-unsaturated ester copolymer (A1) relative to the entire composition is calculated by multiplying the content (mass%) of the structural units derived from unsaturated esters in the ethylene-unsaturated ester copolymer (A1) by the content of the ethylene-unsaturated ester copolymer (A1) in the entire composition.

[0027] The melt mass flow rate (MFR) of the ethylene-unsaturated ester copolymer (A1), measured in accordance with JIS K 7210:1999 at 190°C under a load of 2160 g, is preferably 0.1 g / 10 min or more and 300 g / 10 min or less, more preferably 0.1 g / 10 min or more and 200 g / 10 min or less, even more preferably 1.0 g / 10 min or more and 150 g / 10 min or less, even more preferably 1.0 g / 10 min or more and 100 g / 10 min or less, even more preferably 3.0 g / 10 min or more and 80 g / 10 min or less, even more preferably 5.0 g / 10 min or more and 50 g / 10 min or less, and even more preferably 5.0 g / 10 min or more and 30 g / 10 min or less, from the viewpoint of further improving the balance of heat sealability and extrusion lamination suitability.

[0028] The density of the ethylene-unsaturated ester copolymer (A1) measured in accordance with JIS K 7112:1999 is preferably 900 kg / m 3 More than 960kg / m 3 Less than or equal to 910 kg / m 3 More than 950kg / m 3 or less, more preferably 920 kg / m 3 More than 940kg / m 3 The following is the result. When the density of the ethylene-unsaturated ester copolymer (A1), measured in accordance with JIS K 7112:1999, is not less than the above lower limit, the suitability for extrusion lamination is further improved, and when the density of the ethylene-unsaturated ester copolymer (A1), measured in accordance with JIS K 7112:1999, is not more than the above upper limit, the heat sealability is further improved.

[0029] (At least one member (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof) The at least one member (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof is at least one member selected from a copolymer of ethylene and an unsaturated carboxylic acid, and an ionomer of a copolymer of ethylene and an unsaturated carboxylic acid. The ethylene-unsaturated carboxylic acid copolymer constituting at least one component (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof may be in the form of a block copolymer, a random copolymer, or a graft copolymer. However, in consideration of productivity, it is preferable to use a binary random copolymer, a ternary random copolymer, a graft copolymer of a binary random copolymer, or a graft copolymer of a ternary random copolymer, and more preferably a binary random copolymer or a ternary random copolymer.

[0030] The unsaturated carboxylic acid in the at least one member (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof includes, for example, one or more members selected from the group consisting of acrylic acid, methacrylic acid, 2-ethylacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, maleic anhydride, fumaric anhydride, itaconic anhydride, monomethyl maleate, monoethyl maleate, and the like. Among these, the unsaturated carboxylic acid preferably includes one or two selected from the group consisting of acrylic acid and methacrylic acid, and more preferably includes methacrylic acid, from the viewpoint of further improving the productivity and sanitation of at least one (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof.

[0031] The ethylene-unsaturated carboxylic acid copolymer constituting at least one component (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof preferably comprises an ethylene-(meth)acrylic acid copolymer, more preferably an ethylene-methacrylic acid copolymer.

[0032] The ethylene-unsaturated carboxylic acid copolymer constituting at least one component (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof is a copolymer in which at least ethylene and an unsaturated carboxylic acid are copolymerized, and may be a ternary or higher multi-component copolymer in which a third copolymerization component is further copolymerized. Examples of the third copolymerization component include unsaturated carboxylic acid esters (e.g., (meth)acrylic acid alkyl esters such as methyl acrylate, ethyl acrylate, isobutyl acrylate, n-butyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, isobutyl methacrylate, n-butyl methacrylate, isooctyl methacrylate, 2-ethylhexyl methacrylate, dimethyl maleate, and diethyl maleate), vinyl esters (e.g., vinyl acetate and vinyl propionate), unsaturated hydrocarbons (e.g., propylene, butene, 1,3-butadiene, pentene, 1,3-pentadiene, and 1-hexene), oxides such as vinyl sulfate and vinyl nitrate, halogen compounds (e.g., vinyl chloride and vinyl fluoride), vinyl group-containing primary and secondary amine compounds, carbon monoxide, and sulfur dioxide. Among these, the third copolymerization component is preferably an unsaturated carboxylic acid ester, more preferably a (meth)acrylic acid alkyl ester (the alkyl moiety preferably has 1 or more and 4 or less carbon atoms). These other copolymerization components may be used alone or in combination of two or more.

[0033] Furthermore, the at least one member (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof may be an ionomer of a copolymer of ethylene and an unsaturated carboxylic acid. Examples of ionomers of unsaturated carboxylic acids include monovalent metal ions such as sodium, lithium, potassium, silver, and mercury, and polyvalent metal ions such as zinc, magnesium, calcium, cobalt, nickel, manganese, lead, titanium, strontium, barium, beryllium, aluminum, iron, cadmium, and tin. These metal ions may be used alone or in combination of two or more. Among these, from the viewpoint of easier availability of industrially produced products, the ionomer of unsaturated carboxylic acid preferably contains one or more metal ions selected from the group consisting of sodium, lithium, potassium, zinc, magnesium, aluminum, and barium, more preferably contains one or more metal ions selected from the group consisting of sodium, zinc, and magnesium, and even more preferably contains one or two metal ions selected from the group consisting of sodium and zinc. In addition to the above metal ions, the ionomer of unsaturated carboxylic acid may also contain amino compounds such as ammonia, methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, diethylenetriamine, triethylenetetramine, and 1,3-dimethylaminocyclohexane.

[0034] The content of ethylene-derived structural units in the at least one (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof is preferably 75% by mass or more and 99% by mass or less, more preferably 80% by mass or more and 97% by mass or less, even more preferably 85% by mass or more and 95% by mass or less, and even more preferably 85% by mass or more and 92% by mass or less, when the entire at least one (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof is taken as 100% by mass, from the viewpoint of further improving the balance of performance such as heat resistance, mechanical strength, water resistance, processability, and productivity.

[0035] The content of structural units derived from unsaturated carboxylic acid in the at least one (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof is preferably 1% by mass or more and 25% by mass or less, more preferably 3% by mass or more and 20% by mass or less, even more preferably 5% by mass or more and 15% by mass or less, and still more preferably 8% by mass or more and 15% by mass or less, when the entire at least one (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof is taken as 100% by mass. When the content of structural units derived from unsaturated carboxylic acid in at least one selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof (A2) is not less than the above-mentioned lower limit, the performance balance between transparency and flexibility is further improved, and when the content of structural units derived from unsaturated carboxylic acid in at least one selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof (A2) is not more than the above-mentioned upper limit, the processability is further improved.

[0036] The content of structural units derived from monomers other than ethylene and unsaturated carboxylic acid in the at least one (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof is preferably 0% by mass or more and 10% by mass or less, more preferably 0% by mass or more and 8% by mass or less, and even more preferably 0% by mass or more and 6% by mass or less, when the entire at least one (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof is taken as 100% by mass, from the viewpoint of further improving flexibility, etc.

[0037] Furthermore, the content of structural units derived from unsaturated carboxylic acid in at least one (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof relative to the entire composition is preferably 1% by mass or more and 50% by mass or less, more preferably 3% by mass or more and 40% by mass or less, even more preferably 5% by mass or more and 30% by mass or less, and even more preferably 8% by mass or more and 20% by mass or less. When the content of the structural units derived from unsaturated carboxylic acid in at least one (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof relative to the entire composition is not less than the above-mentioned lower limit, the heat sealability is further improved, and when the content of the structural units derived from unsaturated carboxylic acid in at least one (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and an ionomer thereof relative to the entire composition is not more than the above-mentioned upper limit, the suitability for extrusion lamination is further improved.

[0038] Here, the content of ethylene-derived structural units, the content of unsaturated carboxylic acid-derived structural units, and the content of structural units derived from monomers other than ethylene and unsaturated carboxylic acid in at least one (A2) selected from an ethylene-unsaturated carboxylic acid copolymer and its ionomer can be measured, for example, by Fourier transform infrared absorption spectroscopy (FT-IR).

[0039] The degree of neutralization of the ionomer of the ethylene-unsaturated carboxylic acid copolymer in the at least one (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof is preferably 80% or less, from the viewpoint of further improving the balance of performance such as flexibility, adhesiveness, mechanical strength, processability, etc. Furthermore, from the viewpoint of further improving the balance of performance such as transparency, adhesiveness, and processability, the degree of neutralization of the ionomer of the ethylene-unsaturated carboxylic acid copolymer in the at least one (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof is more preferably 1% or more and 70% or less, even more preferably 5% or more and 60% or less, even more preferably 10% or more and 40% or less, and even more preferably 15% or more and 40% or less. The degree of neutralization of the ionomer of the ethylene-unsaturated carboxylic acid copolymer in at least one of (A2) an ethylene-unsaturated carboxylic acid copolymer and its ionomer is the ratio (mol %) of the number of moles of carboxy groups neutralized with metal ions to the number of moles of all carboxy groups contained in the ethylene-unsaturated carboxylic acid copolymer. Here, the degree of neutralization of the ionomer of the ethylene-unsaturated carboxylic acid copolymer in the at least one component (A2) selected from the ethylene-unsaturated carboxylic acid copolymer and its ionomer can be measured, for example, by incineration residue analysis.

[0040] The ethylene-unsaturated carboxylic acid copolymer (A2) at least one selected from the ethylene-unsaturated carboxylic acid copolymer and its ionomer can be obtained by radical polymerization of each polymerization component under high temperature and high pressure. Also, the ionomer of the ethylene-unsaturated carboxylic acid copolymer (A2) at least one selected from the ethylene-unsaturated carboxylic acid copolymer and its ionomer can be obtained by reacting such an ethylene-unsaturated carboxylic acid copolymer with an oxide, hydroxide, carbonate, or the like containing a metal ion. Furthermore, at least one type (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof may be commercially available products.

[0041] From the viewpoint of further improving the heat sealability, the density of at least one selected from the ethylene-unsaturated carboxylic acid copolymer and its ionomer (A2), measured in accordance with JIS K 7112:1999, is preferably 900 kg / m 3 More than 980kg / m 3 Less than or equal to 910 kg / m 3 More than 960kg / m 3 or less, more preferably 920 kg / m 3 More than 960kg / m 3 or less, more preferably 930 kg / m 3 More than 950kg / m 3 The following is the result.

[0042] The melt mass flow rate (MFR) of at least one selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof (A2), measured in accordance with JIS K 7210:1999 at 190°C under a load of 2160 g, is preferably 0.01 g / 10 min or more and 300 g / 10 min or less, more preferably 0.01 g / 10 min or more and 100 g / 10 min or less, even more preferably 0.1 g / 10 min or more and 50 g / 10 min or less, even more preferably 0.5 g / 10 min or more and 30 g / 10 min or less, even more preferably 0.5 g / 10 min or more and 20 g / 10 min or less, and even more preferably 0.8 g / 10 min or more and 10 g / 10 min or less. When the melt mass flow rate (MFR) of at least one selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof (A2) measured according to JIS K 7210:1999, under conditions of 190°C and 2160g load, is equal to or higher than the above lower limit, moldability and processing stability can be further improved. When the melt mass flow rate (MFR) of at least one selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof (A2) measured according to JIS K 7210:1999, under conditions of 190°C and 2160g load, is equal to or lower than the above upper limit, the balance of performance such as heat resistance and mechanical strength can be further improved.

[0043] <Decomposer (B)> The composition of this embodiment contains a decomposing agent (B). The decomposing agent (B) contains a plurality of fatty acid metal salts, and may contain two or more types of fatty acid metal salts. From the viewpoint of further improving decomposition properties, the decomposing agent (B) preferably contains two or more and four or less types, more preferably two or more and three or less types, and even more preferably two types of fatty acid metal salts.

[0044] The plurality of fatty acid metal salts preferably contain a plurality of metal elements from the viewpoint of further improving decomposability. From the viewpoint of further improving decomposition properties, it is preferable that the oxidation numbers of the multiple metal elements are different from each other, and for example, a combination of divalent and trivalent, a combination of divalent and tetravalent, or a combination of trivalent and tetravalent, etc. can be used.

[0045] The plurality of metal elements forming the fatty acid metal salt preferably include a transition metal element and a rare earth element, from the viewpoint of further improving decomposability. The transition metal element preferably includes one or more elements selected from the group consisting of titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, zirconium, niobium, molybdenum, technetium, ruthenium, palladium, silver, cadmium, and the like. The rare earth element preferably includes one or more elements selected from the group consisting of scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium.

[0046] The multiple metal elements that form the fatty acid metal salt are preferably a combination of a transition metal element and a rare earth element, and more preferably a combination of manganese (oxidation state: divalent or trivalent) as the transition metal element and cerium (oxidation state: trivalent or tetravalent) as the rare earth element.

[0047] The fatty acids forming the plurality of fatty acid metal salts may be one type or a combination of two or more types. The fatty acid may be saturated or unsaturated fatty acid having 12 or more carbon atoms, and preferably includes one or more selected from the group consisting of lauric acid, myristic acid, pentadecylic acid, palmitic acid, margaric acid, stearic acid, arachidic acid, heneicosylic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, melissic acid, myristoleic acid, palmitoleic acid, sapienic acid, oleic acid, elaidic acid, vaccenic acid, gadoleic acid, eicosenoic acid, erucic acid, and nervonic acid.

[0048] The fatty acids that form the multiple fatty acid metal salts preferably contain fatty acids having 12 to 24 carbon atoms, more preferably contain fatty acids having 16 to 20 carbon atoms, and even more preferably contain fatty acids having 18 carbon atoms.From the viewpoint of further improving the balance of degradability and stability, the fatty acids preferably contain one or two acids selected from the group consisting of stearic acid and oleic acid, and even more preferably contain stearic acid.

[0049] From the viewpoint of further improving degradability and stability, the multiple fatty acid metal salts preferably include one or more selected from the group consisting of manganese oleate, cerium oleate, manganese stearate, and cerium stearate, more preferably a combination of manganese oleate and cerium oleate, or a combination of manganese stearate and cerium stearate, and even more preferably a combination of manganese stearate and cerium stearate.

[0050] The cracking agent (B) preferably contains petroleum carbonized oil, which allows the cracking agent (B) to be more uniformly dispersed in the composition. The petroleum-derived oil preferably includes one or more selected from the group consisting of mineral oil, highly refined base oil, high viscosity index base oil and chemically synthesized oil.

[0051] From the viewpoint of further improving dispersibility, the content of the petroleum carbonized oil is preferably 5 parts by mass or more and 30 parts by mass or less, more preferably 8 parts by mass or more and 25 parts by mass or less, and even more preferably 10 parts by mass or more and 20 parts by mass or less, relative to 100 parts by mass of the cracking agent (B).

[0052] In the composition of the present embodiment, the content of the decomposing agent (B) is preferably 0.02 parts by mass or more and 2 parts by mass or less, more preferably 0.1 parts by mass or more and 1.8 parts by mass or less, even more preferably 0.3 parts by mass or more and 1.5 parts by mass or less, even more preferably 0.5 parts by mass or more and 1.3 parts by mass or less, and even more preferably 0.8 parts by mass or more and 1.3 parts by mass or less, relative to 100 parts by mass of the composition. When the content of the decomposing agent (B) is equal to or greater than the above lower limit, the decomposition property can be further improved and the time required for decomposition can be further shortened. When the content of the decomposing agent (B) is equal to or less than the above upper limit, the physical properties of the molded article obtained from the composition can be further improved.

[0053] The composition of the present embodiment may further contain a polyolefin resin (C), which further improves the dispersibility of the decomposing agent (B) in the composition. The monomer constituting the polyolefin resin (C) preferably contains one or more selected from the group consisting of α-olefins having about 2 to 10 carbon atoms, such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, and 1-octene, and more preferably contains ethylene. The monomer constituting the polyolefin resin (C) further preferably contains low-density polyethylene. Such α-olefins may be used singly or in combination of two or more. From the viewpoint of further improving the dispersibility of the decomposition agent (B), the content of the polyolefin resin (C) is preferably 300 parts by mass or more and 1,000 parts by mass or less, more preferably 350 parts by mass or more and 800 parts by mass or less, and even more preferably 400 parts by mass or more and 500 parts by mass or less, per 100 parts by mass of the decomposition agent (B).

[0054] The melt mass flow rate (MFR) of the polyolefin resin (C) measured in accordance with JIS K 7210:1999 under conditions of 190°C and a load of 2160 g is, from the viewpoint of further improving the dispersibility of the decomposition agent (B), preferably 0.1 g / 10 minutes or more and 300 g / 10 minutes or less, more preferably 0.1 g / 10 minutes or more and 200 g / 10 minutes or less, even more preferably 1.0 g / 10 minutes or more and 150 g / 10 minutes or less, even more preferably 1.0 g / 10 minutes or more and 100 g / 10 minutes or less, even more preferably 3.0 g / 10 minutes or more and 80 g / 10 minutes or less, even more preferably 5.0 g / 10 minutes or more and 50 g / 10 minutes or less, and even more preferably 5.0 g / 10 minutes or more and 30 g / 10 minutes or less.

[0055] The polyolefin resin (C) may be preliminarily mixed with the decomposing agent (B). By preparing a masterbatch by mixing the decomposing agent (B) and the polyolefin resin (C) and then mixing the masterbatch with the copolymer (A), the compatibility between the decomposing agent (B) and the copolymer (A) can be further improved, and the dispersibility of the decomposing agent (B) in the composition can be further improved.

[0056] <Other resins> The composition of this embodiment may contain a resin other than copolymer (A) as long as the object of the present invention is not impaired. The resin other than copolymer (A) is preferably one or more selected from the group consisting of polyethylene, polypropylene, polybutadiene, polyacetal, polyamide, polyethylene terephthalate, polycarbonate, polystyrene, polyphenylene sulfide, polybutylene terephthalate, polyvinyl chloride, ABS resin, and AS resin.

[0057] <Other ingredients> The composition of the present embodiment may contain various additives within the scope of the present invention, such as one or more additives selected from the group consisting of antistatic agents, antifogging agents, antiblocking agents, slip agents, and pigments.

[0058] <Method for preparing the composition> The composition of this embodiment can be prepared, for example, by simultaneously or continuously mixing the copolymer (A), the decomposing agent (B), and any additives, with no particular restriction on the order of mixing. As described above, the decomposing agent (B) and the polyolefin resin (C) may be premixed to prepare a masterbatch, which is then mixed with the copolymer (A). The preferred preparation method is melt mixing using a single-screw extruder, a twin-screw extruder, a Banbury mixer, a roll, various kneaders, or the like. For example, a method of dry-blending and mixing the copolymer (A), the decomposing agent (B), and, if necessary, other components; a method of melt-kneading the copolymer (A), the decomposing agent (B), and, if necessary, other components in an extruder; and the like can be applied.

[0059] <Confirmation of decomposition> The degradability of the composition of this embodiment can be evaluated by preparing a molded body made of the composition of this embodiment, storing it for a certain period of time under the storage conditions 1 to 3 below, and then checking whether cracks occur in the molded body. (Storage conditions) 1 (heating acceleration): 60℃, 2000 hours 2 (Xenon weather resistance test): Light source: Xenon arc lamp, Xenon irradiation: 180 W / m 2 ,Exposure time: 850 hours,Temperature (black panel temperature): 63℃,Condition:Water sprayed (rainfall conditions) 3 (Outdoor exposure test): Left on a roof (outside of shade) for 2000 hours from July to October

[0060] 2. Molded body The molded article of this embodiment is obtained from the composition of this embodiment. The shape of the molded product of this embodiment is not limited, and may be, for example, a sheet, film, block, pellet, fiber, or the like. The molded article of this embodiment can be formed by a known method, such as extrusion molding, injection molding, compression molding, or vacuum molding. Furthermore, the uses of the molded article of this embodiment are not limited, and it can be used as films and sheets, packaging containers, machine parts, pipes, building materials, daily necessities and miscellaneous goods, foam products, etc. Specifically, it can be suitably used for disposable products and outdoor products, and can be used as various degradable resin products such as agricultural films, disposable diapers, product packaging bags, garbage bags, food trays, beverage cups, civil engineering vegetation nets, plastic drainage materials for wastewater, tree protection materials, and bags for cultivating fungi and plants.

[0061] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various other configurations can also be adopted. Furthermore, the present invention is not limited to the above-described embodiment, and modifications and improvements within the scope of achieving the object of the present invention are included in the present invention. [Example]

[0062] The present embodiment will be described in detail below with reference to examples, etc. However, the present embodiment is not limited to the descriptions of these examples.

[0063] <Material> The components used were as follows: The MFR (g / 10 min) was measured in accordance with JIS K7210:1999 under the conditions of 190°C and a load of 2160 g. 3 ) was measured in accordance with JIS K 7112:1999. (Ethylene-unsaturated ester copolymer (A1)) Ethylene vinyl acetate (EVA): Vinyl acetate content: 10% by mass, MFR: 9 g / 10 min, density: 930 kg / m 3 (At least one member (A2) selected from ethylene-unsaturated carboxylic acid copolymers and ionomers thereof) Ethylene-methacrylic acid copolymer (EMAA): methacrylic acid content: 10.5% by mass, MFR: 8 g / 10 min, density: 940 kg / m 3 (Decomposer masterbatch) The decomposition agent masterbatch contains a decomposition agent (B) and a polyolefin resin (C) (LDPE, described below). In Table 1, the decomposition agent (B) and the polyolefin resin (C) are added together as a decomposition agent masterbatch. Decomposer masterbatch: P-Life Green 20 manufactured by P-Life Japan Inc., LDPE: decomposer (B) = 80% by mass: 20% by mass. Decomposer (B) is composed of two types of aliphatic monocarboxylic acid salts and petroleum carbonized oil. The petroleum carbonized oil content in decomposer (B) is 10-20% by mass. The MFR of LDPE is 8.1 g / 10 min.

[0064] <Preparation of a four-layer laminate> (Creating support 1) A 15-μm-thick low-density polyethylene (density: 923 kg / m) film was laminated on a biaxially oriented polyethylene terephthalate (PET) film (Lumirror®, manufactured by Toray Industries, Inc., thickness: 12 μm) using an extrusion laminator (manufactured by Sumitomo Heavy Industries Modern Co., Ltd.) with a screw diameter of 65 mm, at a resin temperature below the die of 320°C. 3A layer of an anchor coating agent (hereinafter abbreviated as ac; Seikadyne 2710A (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.): Seikadyne 2710C (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.): ethyl acetate = 2% by mass: 4% by mass: 31% by mass, solid concentration: 7% by mass) was laminated on top of the layer of an anchor coating agent (hereinafter abbreviated as ac; Seikadyne 2710A (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.): ethyl acetate = 2% by mass: 4% by mass: 31% by mass, solid concentration: 7% by mass) to prepare a substrate 1 having a structure of PET film (12 μm) / ac·LDPE (15 μm).

[0065] Next, the resins dry-blended in the proportions shown in Table 1 were melt-extruded from a T-die onto a support 2 (PET layer (12 μm): Toray Industries, Inc., Lumirror®) using a 40 mmφ single-extrusion laminator (Tanabe Plastics Machine Co., Ltd., L / D = 32) under extrusion conditions of 220°C extruder die outlet resin temperature, 15 m / min take-up speed, and a sealant layer thickness of 50 μm after molding. A PET film (25 μm) was inserted from the sand substrate side to produce a three-layer laminate (PET (12 μm) / evaluation resin layer (50 μm) / PET (25 μm)). The PET films on both sides of the resulting three-layer laminate were peeled off, and the resulting film was designated the evaluation resin (50 μm).

[0066] Next, using the 40 mmφ single extrusion laminator, low-density polyethylene (density 923 kg / m) was laminated onto the support 1 prepared in advance under extrusion conditions such that the extruder die outlet resin temperature was 330°C, the take-up speed was 50 m / min, and the thickness of the sandwich laminate after molding was 15 μm. 3 , MFR: 3.7 g / 10 min, melting point: 111°C) was sandwich-laminated into a film, and the above-mentioned evaluation resin was inserted from the sandwich substrate side to a thickness of 50 μm to prepare a four-layer laminate (layer structure: PET (12 μm) / ac·LDPE (15 μm) / LDPE (15 μm) / evaluation resin (50 μm)).

[0067] <Preparation of single layer film> The resins were dry-blended in the proportions shown in Table 1 and melt-extruded from a T-die using the above-mentioned 40 mmφ single extrusion laminator at an extruder die outlet resin temperature of 220°C. The molten film was then press-molded using a heat press to produce a monolayer film consisting of an evaluation resin sheet measuring 270 mm in length, 270 mm in width, and 2 mm in thickness.

[0068] <Evaluation of heat sealability> The four-layer laminate of each example obtained above was cut out in the MD direction (the direction of resin flow when the four-layer laminate was produced), and two of the cut four-layer laminates were placed one on top of the other with the surfaces of the resin to be evaluated laminated together. The laminate was then heat-sealed using a heat sealer under the following conditions to produce a sample. (Heat sealing conditions) Sealing device: Heat sealer (Tester Sangyo Co., Ltd., TP701C Heat Seal Tester, seal width: 10 mm) Sealing temperature: 140℃ Sealing time: 1 second Sealing pressure: 0.2MPa

[0069] The resulting samples were cut into 15 mm wide test pieces and stored at 23°C and 50% RH for at least 24 hours. After storage, the test pieces were subjected to a tensile test in accordance with JIS K 7161-1:2014 using a tensile tester (Shimadzu Corporation, EZ-SX, maximum capacity: 100 N) at a tensile speed of 300 mm / min, 180° peeling in the MD direction, and the evaluation resin layer was peeled from the LDPE layer to measure the heat seal strength (N / 15 mm). Measurements were performed five times for each example, and the average value was calculated. A heat seal strength of 20 N / 15 mm or greater was considered acceptable. The results are shown in Table 1.

[0070] <Evaluation of degradability> The monolayer films of each example obtained above were placed under the following storage conditions 1 to 4, and then the presence or absence of cracks on the surface of the monolayer film was visually inspected. The results are shown in Table 1. (Storage conditions) 1 (unaccelerated): 2000 hours in a dark room at 23°C and 50% RH 2 (heating acceleration): 60°C oven, 2000 hours 3 (Xenon weathering test): Apparatus: Xenon weathering tester (ATLAS, Ci4000 type), Light source: Xenon arc lamp, Xenon irradiation: 180 W / m 2 Exposure time: 850 hours, Temperature (black panel temperature): 63°C, Conditions: Water spray (rainfall condition, 24 times water spray in 120 minutes) 4 (Outdoor exposure test): Left on a rooftop (outside of shade) for 2000 hours from July to October

[0071] [Table 1]

[0072] As can be seen from Table 1, in Comparative Examples 1 and 2, no cracks were observed in the monolayer film under any of the storage conditions, whereas in Examples 1 and 2, cracks were observed in the monolayer film under any of the storage conditions of accelerated heating, weather resistance test, and outdoor exposure, demonstrating improved decomposition properties. Furthermore, Examples 1 and 2 had heat sealability equivalent to that of Comparative Examples 1 and 2, which did not contain the decomposer (B).

Claims

1. A composition comprising a copolymer (A) containing one or more selected from the group consisting of ethylene-unsaturated ester copolymers (A1) and ethylene-unsaturated carboxylic acid copolymers and their ionomers (A2), and a decomposition agent (B) containing a plurality of fatty acid metal salts.

2. The composition according to claim 1, wherein the ethylene-unsaturated ester copolymer (A1) comprises one or more selected from the group consisting of ethylene-vinyl ester copolymers and ethylene-unsaturated carboxylic acid copolymers.

3. The composition according to claim 1, wherein at least one (A2) selected from the ethylene-unsaturated carboxylic acid copolymer and its ionomer comprises an ethylene-(meth)acrylic acid copolymer.

4. The composition according to claim 1, wherein the content of the decomposing agent (B) is 0.02 parts by mass or more and 2 parts by mass or less per 100 parts by mass of the composition.

5. The composition according to claim 1, wherein the decomposing agent (B) contains petroleum carbonized oil.

6. The composition according to claim 5, wherein the content of the petroleum carbonized oil is 5 parts by mass or more and 30 parts by mass or less per 100 parts by mass of the decomposition agent (B).

7. The composition according to claim 1, wherein the plurality of fatty acid metal salts contain a plurality of metal elements, and the oxidation states of the plurality of metal elements are different from each other.

8. The composition according to claim 1, wherein the plurality of fatty acid metal salts contain a plurality of metal elements, and the plurality of metal elements include transition metal elements and rare earth elements.

9. The composition according to claim 1, wherein the fatty acids that form the plurality of fatty acid metal salts include fatty acids having 12 to 24 carbon atoms.

10. The composition according to claim 1, wherein the plurality of fatty acid metal salts include one or more selected from the group consisting of manganese oleate, cerium oleate, manganese stearate, and cerium stearate.

11. Further containing polyolefin resin (C), The composition according to claim 1, wherein the content of the polyolefin resin (C) is 300 parts by mass or more per 100 parts by mass of the decomposing agent (B).

12. A molded article obtained from the composition according to any one of claims 1 to 11.