Ionomer

Abstract

The present invention provides an ionomer having high strain-hardening properties and excellent moldability.　The ionomer contains: a structural unit (A) derived from at least one member selected from the group consisting of ethylene and an α-olefin having 3 to 20 carbon atoms; a structural unit (B) having at least one member selected from the group consisting of a carboxyl group and a dicarboxylic acid anhydride group; and a structural unit (C) having a carboxylic acid metal salt group. The ionomer has 50 or fewer methyl branches per 1,000 carbon atoms or has a total number of ethyl and butyl branches of less than 4.2 per 1,000 carbon atoms. When the maximum elongation viscosity after strain hardening is defined as ηmax(t1), a time t in question is defined as t1, and an approximate straight line of the elongation viscosity before stain hardening is defined as ηlin(t), ηmax(t1) and ηlin(t1) satisfy ηmax(t1)> ηlin(t1), and further satisfy formula (α) or (β).　Formula (α): ηmax(t1)>1.9 ηlin(t1)1.1 Formula (β): ηmax(t1)≥1.9 ηlin(t1)0.7

Description

Ionomer

[0001] This invention relates to ionomers, and more specifically to ethylene-based ionomers. More specifically, it relates to ionomers that have excellent moldability with a good balance between fluidity and strain hardening properties.

[0002] Ethylene-based ionomers use an ethylene-unsaturated carboxylic acid (or dicarboxylic acid anhydride) copolymer (hereinafter also called an acid copolymer) as the base resin, and have carboxylic acid bases in which the carboxyl groups in the acid copolymer are neutralized by metal ions such as sodium, magnesium, and zinc. Due to this structure, ethylene-based ionomers are said to form aggregates (ionic aggregates) through intermolecular bonds via these metal ions. Ethylene-based ionomers are characterized by their toughness, rigidity, and high transparency (Patent Document 1). Acid copolymers produced by high-pressure radical polymerization have many irregular long-chain and short-chain branches, as shown in the image diagram in Figure 1, and inherently possess strain-curing properties like low-density polyethylene (LDPE). It is also known that the strain-curing properties of such acid copolymers can be improved by using an ionomer of zinc, sodium, or magnesium ions, due to the presence of aggregates (Non-Patent Document 1).

[0003] Currently, commercially available ethylene-based ionomers include "Surlyn®" developed by DuPont and "Hymiran®" developed by Mitsui-Dow Polychemicals. Both of these ethylene-based ionomers use acid copolymers produced by high-pressure radical polymerization as their base resin. These ionomers using acid copolymers produced by high-pressure radical polymerization have the drawback of insufficient strength and impact resistance due to the aforementioned branched structure.

[0004] To improve the shortcomings of ethylene-based ionomers produced by high-pressure radical polymerization, the improvement of mechanical properties by blending ionomers with different types of metal ions is being investigated. For example, Non-Patent Literature 2 reports that blending two types of ethylene-based ionomers with different metal ions (Na and Zn, Li and Zn, Mg and Zn) using an acid copolymer produced by high-pressure radical polymerization as the base resin improves mechanical properties such as flexural modulus.

[0005] Furthermore, in order to improve upon the shortcomings of ethylene-based ionomers produced by high-pressure radical polymerization, methods for producing acid copolymers and olefin copolymers that serve as their raw materials, other than high-pressure radical polymerization, have been developed in recent years. Specifically, methods using late-stage transition metal catalysts have been reported (Patent Documents 2 and 3). First, a copolymer of ethylene and t-butyl acrylate is produced in the presence of a late-stage transition metal catalyst. Next, the obtained copolymer is modified into an ethylene-acrylic acid copolymer (acid copolymer) by heat or acid treatment. Subsequently, the obtained acid copolymer is neutralized with metal ions such as sodium or zinc to produce an ethylene-based ionomer.

[0006] Furthermore, regarding ionomers in which the metal atom (ion) is magnesium, there is also the following report (Patent Document 4). First, maleic anhydride is graft-modified onto an ethylene-cyclic olefin copolymer (COC). Next, the modified copolymer is reacted with magnesium stearate to produce an ethylene-based ionomer.

[0007] On the other hand, Pauling's electronegativity is known as an index for estimating the bond enthalpy between atoms of elements with different electronegativity and for qualitatively evaluating the polarity of bonds (Non-Patent Literature 3). Furthermore, building upon Pauling's electronegativity, an index has been developed for classifying binary compounds into ionic, covalent, or metallic types, using the difference in elemental electronegativity (Δχ) and the average electronegativity (χ). 平均 The van Aker-Ketler triangle, based on ), is known (Non-Patent Literature 6 and 7).

[0008] U.S. Patent No. 3,264,272, Japanese Unexamined Patent Publication No. 2016-79408, Japanese Unexamined Patent Publication No. 2020-143276, Japanese Unexamined Patent Publication No. 2020-158682

[0009] Polymer, vol. 35, no. 26, pp. 5722-5727, 1994 Macromolecules, vol. 27, No. 2, pp. 372-378, 1994 Hiroshi Ogino, Hiromi Tobita, and Masaaki Okazaki, "Basic Inorganic Chemistry," Tokyo Kagaku Dojin, 2nd edition, 2006, p. 30 L. A. UTRACKI, "Polymer Alloys and Polymer Blends," Tokyo Kagaku Dojin, 1st edition, 1991, pp. 262-265 Journal of the Rheology Society of Japan, vol. 19, 1991, pp. 174-180 Schriver & Atkins Inorganic Chemistry (Part 1), Tokyo Kagaku Dojin, 6th edition, 2016, p. 69 J. Phys. Chem., vol. 98, no. 27, P6699-6703, 1994

[0010] There is a need for ionomers that exhibit excellent moldability while maintaining excellent properties such as mechanical strength and transparency. The ionomers disclosed in Patent Document 1 and Non-Patent Document 1 are manufactured by high-pressure radical polymerization, and further improvements in strength and impact resistance are required.

[0011] Non-patent document 2 discloses that the flexural modulus and yield strength can be improved by blending an acid copolymer produced by high-pressure radical polymerization with ethylene-based ionomers of different metal ions as a base resin. However, the improved physical properties relate to minute deformation in the solid state, and there is no description of improving large-scale deformation in the molten state, which is related to moldability such as strain hardening.

[0012] Patent Document 2 describes an ionomer produced using a late-stage transition metal catalyst, which has a substantially linear structure as its base resin, resulting in an ionomer with excellent thermal properties and mechanical strength. However, focusing on metal ions from groups 1, 2, and 12 of the periodic table as the metal ions constituting the ionomer, only sodium ionomer has been substantially studied, and there is no description of the properties of ionomers containing other metal ions.

[0013] Patent Document 3 describes a ternary ionomer obtained using a late transition metal catalyst, which has a substantially linear structure and a structural unit (B) derived from a monomer having at least one selected from the group consisting of a carboxyl group and a dicarboxylic acid anhydride group, and which has excellent tensile strength, transparency, and metal adhesion. However, when considering metal ions constituting the ionomer, the focus has been on metal ions from groups 1, 2, and 12 of the periodic table, and the ionomers substantially studied have only a single metal atom of sodium or zinc. There is no description of the physical properties of ionomers having metal atoms other than these.

[0014] Patent Document 4 describes how an ionomer with a substantially linear structure can be obtained using a maleic anhydride graft-modified ethylene-COC as the base resin, exhibiting excellent high-temperature dimensional stability and transparency. However, the document only describes ionomers containing a single metal atom of potassium or magnesium, and does not describe the physical properties of ionomers containing other metal atoms.

[0015] Although the ionomers disclosed in Patent Documents 2 to 4 have excellent mechanical strength and transparency, localized thinning may occur during molding processes such as blow molding and film molding, and further improvement in moldability is required.

[0016] In view of the circumstances of the prior art, the present invention aims to provide an ionomer that exhibits high strain hardening properties and excellent moldability.

[0017] The inventors of the present invention considered that in order to prevent local thinning during molding, make the wall thickness of the molded product uniform, and improve the moldability, it is necessary to enhance the strain hardening property of the ionomer. When a linear ionomer was used to enhance mechanical strength and transparency, it was found that since the ionomer has substantially no branched structure such as LDPE, it has almost no strain hardening property. In order to enhance the strain hardening property of the ionomer, the inventors focused on the type of metal atom constituting the ionomer and the relationship between specific data obtained from a double logarithmic plot of the extensional viscosity η(t) obtained by uniaxial extensional viscosity measurement and the extension time t, and conducted intensive studies. As a result, by using an ionomer having a substantially linear structure, selecting a specific metal atom as the metal atom constituting the ionomer, and making η ｍａｘ (t １ ) and η ｌｉｎ (t １ ) have a specific relationship, it was found that the obtained ionomer has significantly superior strain hardening property compared to conventional ionomers, and the present invention was thus achieved.

[0018] That is, the present invention relates to the following [1] to

[16] . [l] A structural unit (A) derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms; a structural unit (B) having at least one selected from the group consisting of a carboxy group and a dicarboxylic anhydride group; and a structural unit (C) having a carboxylic acid metal salt group, wherein the ionomer contains １３ the number of methyl branches calculated by C-NMR is 50 or less per 1,000 carbon atoms, or the total of the number of ethyl branches and the number of butyl branches is less than 4.2 per 1,000 carbon atoms, and in a double logarithmic plot of the extensional viscosity η(t) (unit: Pa·s) obtained by uniaxial extensional viscosity measurement at 140°C and an extensional strain rate of 0.2 [1 / sec] and the extension time t (unit: sec), the maximum extensional viscosity after strain hardening is η ｍａｘ (t １ ), the time t at that time is t １ , and when the approximate straight line of the extensional viscosity before strain hardening is η ｌｉｎ (t), η ｍａｘ (t １) and time t １ Extensional viscosity η on the approximate straight line in the above case ｌｉｎ (t １ ) and η ｍａｘ (t １ )>η ｌｉｎ (t １ ), and an ionomer satisfying the following formula (α) or (β). η ｍａｘ (t １ ) > 1.9η ｌｉｎ (t １ ) １．１ Equation (α) η ｍａｘ (t １ ) ≥ 1.9η ｌｉｎ (t １ ) ０．７ Equation (β) Here, the approximate linear relationship of extensional viscosity before strain hardening is: η ｌｉｎ (t) is the tangent line with the smallest slope among the tangent lines to the curve of the log-log plot within the range of extension time t corresponding to a strain amount of 0.2 to 1.0, provided that the slope is 0 or a positive value. Also, η ｍａｘ (t １ ) and η ｌｉｎ (t １ The unit of ) is MPa·second. [2] The above formula (α) is η ｍａｘ (t １ ) > 2.8η ｌｉｎ (t １ ) １．１ The ionomer described in [1]. [3] The above formula (β) is η ｍａｘ (t １ ) ≥ 2.0η ｌｉｎ (t １ ) ０．７ The ionomer described in [1] or [2]. [4] λmax = η ｍａｘ (t １ ) / η ｌｉｎ (t １ The ionomer according to any one of [1] to [3], wherein the degree of strain hardening λmax, as defined by ), is 2.4 or greater. [5] In the structural unit (C), the carboxylic acid metal base is a metal atom M having a Pauling electronegativity χ of 1.83 to 2.54. ３An ionomer according to any one of [1] to [4], comprising at least one of the above. [6] An ionomer according to any one of [1] to [5], wherein the ratio of the mol content of structural unit (C) to the sum of the mol content of structural unit (B) and structural unit (C) is 20 to 70 mol%. [7] An ionomer according to any one of [1] to [6], wherein the ratio of the sum of the mol content of structural unit (B) and structural unit (C) to the sum of the mol content of structural unit (A), structural unit (B), and structural unit (C) is 0.01 to 20.00 mol%. [8] An ionomer according to any one of [1] to [7], wherein structural unit (A) is a structural unit derived from ethylene. [9] A structural unit (A) derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms; a structural unit (B) having at least one selected from the group consisting of a carboxyl group and a dicarboxylic acid anhydride group; and a structural unit (C) having a carboxylic acid metal base, wherein the carboxylic acid metal base is at least two metal atoms. １ and M ２ Contains the above M １ and the M ２ The electronegativity of Polling is χ, respectively. Ｍ１ and χ Ｍ２ When this is the case, χ Ｍ１ -χ Ｍ２ The structural unit (C) having a value of 0.06 or more includes, １３ An ionomer in which the number of methyl branches calculated by C-NMR is 50 or less per 1,000 carbon atoms, or the sum of the number of ethyl branches and butyl branches is less than 4.2 per 1,000 carbon atoms.

[10] χ Ｍ１ -χ Ｍ２ However, the ionomer described in [9] is 0.06 to 1.84.

[11] The M １ is selected from the group consisting of iron, cobalt, nickel, copper, silver, and lead, and the M ２ is selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, and zinc, or the above M １The M is selected from the group consisting of titanium, vanadium, chromium, manganese, and zinc. ２ An ionomer according to [9] or

[10] , wherein the structural unit (A) is selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, and barium.

[12] An ionomer according to any one of [9] to

[11] , wherein the ratio of the mol content of structural unit (C) to the sum of the mol content of structural unit (B) and structural unit (C) is 20 to 70 mol%.

[13] An ionomer according to any one of [9] to

[12] , wherein the ratio of the sum of the mol content of structural unit (B) and structural unit (C) to the sum of the mol content of structural unit (A), structural unit (B), and structural unit (C) is 0.01 to 20.00 mol%.

[14] An ionomer according to any one of [9] to

[13] , wherein structural unit (A) is a structural unit derived from ethylene. A resin composition containing the ionomer described in any one of

[15] [1] to

[14] . A molded article containing the resin composition described in

[16]

[15] .

[0019] According to the present invention, an ionomer having a substantially linear structure is used, specific metal atoms are selected as constituting the ionomer, and the η obtained by uniaxial extensional viscosity measurement is obtained. ｍａｘ (t １ ) and η ｌｉｎ (t １ By either ) and ensuring a specific relationship between them, it is possible to provide an ionomer that exhibits higher strain hardening properties (λmax) and superior moldability compared to conventional ionomers. In particular, by using an ionomer having a substantially linear structure with at least two metal atoms whose Pauling electronegativity difference χ is 0.06 or more, it is possible to provide an ionomer in which the λmax of the ionomer is higher than the value expected from the average value of the λmax of ionomers using each metal atom individually.

[0020] It is an image diagram of the molecular structure of a multi-branched olefin copolymer polymerized by a high-pressure radical polymerization process. It is an image diagram of the molecular structure of a linear olefin copolymer polymerized using a metal catalyst. For the ionomer of Example 4, it is a double logarithmic plot of the elongation viscosity η(t) and the elongation time t obtained by measuring the uniaxial elongation viscosity at 140 °C and an elongation strain rate of 0.2 [1 / sec]. For the ionomers of the examples and comparative examples, η ｍａｘ and η ｌｉｎ is a graph showing the relationship.

[0021] In one aspect of the present invention, the ionomer includes a structural unit (A) derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms; a structural unit (B) having at least one selected from the group consisting of a carboxy group and a dicarboxylic acid anhydride group; and a structural unit (C) having a metal carboxylate group. １３ The number of methyl branches calculated by C-NMR is 50 or less per 1,000 carbon atoms, or the total number of ethyl branches and butyl branches is less than 4.2 per 1,000 carbon atoms. In the double logarithmic plot of the elongation viscosity η(t) (unit: Pa·s) and the elongation time t (unit: s) obtained by measuring the uniaxial elongation viscosity at 140 °C and an elongation strain rate of 0.2 [1 / sec], the maximum elongation viscosity after strain hardening is η ｍａｘ (t １ ), the time t at that time is t １ , and when the approximate straight line of the elongation viscosity before strain hardening is η ｌｉｎ (t), η ｍａｘ (t １ ) and the elongation viscosity η １ on the approximate straight line at time t ｌｉｎ (t １ ) satisfy η ｍａｘ (t １ ) > η ｌｉｎ (t １ ), and satisfy the following formula (α) or (β). η ｍａｘ (t １ ) > 1.9η ｌｉｎ (t １ ) １．１ Formula (α) η ｍａｘ (t １ ) ≥ 1.9η ｌｉｎ (t１ ) ０．７ Formula (β): Here, the approximate straight line of the elongational viscosity before strain hardening: η ｌｉｎ (t) is the tangent line of the curve of the double logarithmic plot within the range of the elongation time t corresponding to a strain amount of 0.2 to 1.0, among which the tangent line with the smallest slope is used, provided that the slope is 0 or a positive value. Also, η ｍａｘ (t １ ) and η ｌｉｎ (t １ ) are in the unit of MPa·s. The ionomer has high strain hardening property, exhibits excellent moldability, and the properties of the obtained molded product such as mechanical strength and transparency are also good.

[0022] In another aspect of the present invention, the ionomer includes a structural unit (A) derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms; a structural unit (B) having at least one selected from the group consisting of a carboxy group and a dicarboxylic acid anhydride group; and a structural unit (C) having a carboxylic acid metal base, wherein the carboxylic acid metal base contains at least two metal atoms M １ and M ２ , and when the electronegativities of the polling of the M １ and the M ２ are respectively χ Ｍ１ and χ Ｍ２ , the structural unit (C) in which χ Ｍ１ - χ Ｍ２ is 0.06 or more, and １３ the methyl branch number calculated by C-NMR is 50 or less per 1,000 carbon atoms or the total of the ethyl branch number and the butyl branch number is less than 4.2 per 1,000 carbon atoms. The ionomer has high strain hardening property, exhibits excellent moldability, and the properties of the obtained molded product such as mechanical strength and transparency are also good.

[0023] The ionomers of the present invention will be described in detail below, item by item. In this specification, "(meth)acrylic acid" means acrylic acid or methacrylic acid. In this specification, "~" indicating a numerical range means that the values ​​written before and after it are included as the lower and upper limits. In this specification, copolymer means a binary or higher copolymer containing at least one structural unit (A) and at least one structural unit (B). In this specification, "ionomer" is a ternary or higher copolymer containing the aforementioned structural unit (A), the aforementioned structural unit (B), and a structural unit (C) having a carboxylic acid metal base. Each structural unit may be of one type or multiple types. The ionomer may further contain other structural units. In this specification, "ionomer" means both a single copolymer and a mixture of multiple copolymers. Furthermore, in this specification, "raw material copolymer" means the raw material copolymer when the ionomer is obtained by modifying a copolymer containing at least one structural unit (A) and at least one structural unit having an alkoxycarbonyl group or at least one structural unit (B) as a raw material. Also, in this specification, "n-" (normal), "i-" (iso), and "t-" (tertiary) are used to represent isomers.In this specification, Pauling's electronegativity means the "Pauling value" in Table 1.4 of "Basic Inorganic Chemistry" by Hiroshi Ogino, Hiromi Tobita, and Masaaki Okazaki, Tokyo Kagaku Dojin, 2nd edition, 2006, p. 30 (Non-Patent Literature 3).In this specification, unless otherwise specified, when simply referred to as electronegativity, it means Pauling's electronegativity.

[0024] 1. Ionomers: The ionomer comprises a structural unit (A) derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms; a structural unit (B) having at least one selected from the group consisting of a carboxyl group and a dicarboxylic acid anhydride group; and a structural unit (C) having a carboxylate metal base. １３The number of methyl branches calculated by C-NMR is 50 or less per 1,000 carbon atoms, or the sum of the number of ethyl branches and butyl branches is less than 4.2 per 1,000 carbon atoms.

[0025] (1) Structural Unit (A) Structural unit (A) is a structural unit derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms. α-olefins have the general formula (1): CH ２ =CHR ２ It is an α-olefin having 3 to 20 carbon atoms, represented by (R ２ (The carbon group is a hydrocarbon group having 1 to 18 carbon atoms, and may have a linear or branched structure.) The carbon number of the α-olefin is more preferably 3 to 12.

[0026] Specific examples of monomers from which structural unit (A) is derived include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 3-methyl-1-butene, and 4-methyl-1-pentene, and may also be ethylene. As for ethylene, in addition to ethylene derived from petroleum raw materials, ethylene derived from non-petroleum raw materials such as plant raw materials, and ethylene derived from chemical recycling can be used. Furthermore, structural unit (A) may be one type or multiple types. Examples of combinations of two types include ethylene-propylene, ethylene-1-butene, ethylene-1-hexene, ethylene-1-octene, propylene-1-butene, propylene-1-hexene, and propylene-1-octene. Examples of combinations of the three include ethylene-propylene-1-butene, ethylene-propylene-1-hexene, ethylene-propylene-1-octene, propylene-1-butene-1-hexene, and propylene-1-butene-1-octene.

[0027] The monomer from which structural unit (A) is derived is preferably ethylene, and may further contain one or more α-olefins having 3 to 20 carbon atoms as needed. The proportion of ethylene contained in the monomer from which structural unit (A) is derived may be 50 to 100 mol%, 70 to 100 mol%, or 90 to 100 mol% relative to the total mol of structural unit (A). From the viewpoint of impact resistance, the above structural unit (A) is preferably a structural unit derived from ethylene.

[0028] (2) Structural Unit (B) Structural unit (B) is a structural unit having at least one selected from the group consisting of a carboxyl group and a dicarboxylic acid anhydride group. Structural unit (B) may be a structural unit derived from a monomer having at least one of a carboxyl group and a dicarboxylic acid anhydride group. As described in the manufacturing method below, it is not necessarily required to be manufactured using a monomer having at least one of a carboxyl group and a dicarboxylic acid anhydride group.

[0029] Examples of monomers having a carboxyl group include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, norbornenedicarboxylic acid, and bicyclo[2,2,1]hepta-2-ene-5,6-dicarboxylic acid. Examples of monomers having a dicarboxylic acid anhydride group include maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, 5-norbornene-2,3-dicarboxylic acid anhydride, 3,6-epoxy-1,2,3,6-tetrahydrophthalic anhydride, and tetracyclo[6.2.1.1 3,6 . 0 2,7 Examples include unsaturated dicarboxylic acid anhydrides such as dodeca-9-ene-4,5-dicarboxylic acid anhydride and 2,7-octadiene-1-ylsuccinic acid anhydride.

[0030] The monomer having at least one of the carboxy group and the dicarboxylic acid anhydride group is preferably acrylic acid, methacrylic acid, or 5-norbornene-2,3-dicarboxylic acid anhydride from the viewpoint of easy industrial availability, and acrylic acid is particularly preferable. Also, the monomer having at least one of the carboxy group and the dicarboxylic acid anhydride group may be one kind or a plurality of kinds. Note that the dicarboxylic acid anhydride group may react with moisture in the air to open the ring and partially become a dicarboxylic acid. As long as it does not depart from the gist of the present invention, the dicarboxylic acid anhydride group may be open-ringed.

[0031] The structural unit (B) may be obtained by a desorption reaction by heat or an acid. The "desorption reaction" here may be a deprotection reaction of an ester. The reaction conditions are not particularly limited as long as they are reaction conditions used for general deprotection of esters. As the heat or acid that is the reaction condition of the desorption reaction, generally adopted conditions or reagents can be adopted. Conditions such as temperature and reagents in the desorption reaction are well-known to those skilled in the art, and they can be adopted by appropriately combining them. Note that the deprotection reaction of the ester may be carried out partially, and in that case, a structural unit having an alkoxycarbonyl group will be present in the ionomer.

[0032] The structural unit (B) is, for example, of the general formula (2): CH ２ =C(R ３１ )-X-CO ２ R ３２ It may be obtained by copolymerizing at least one of the compounds represented as a monomer and then converting the alkoxycarbonyl group to a carboxy group by the above-mentioned heat or acid desorption reaction. Here, R ３１ is a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a hydrocarbon group having 1 to 10 carbon atoms substituted with at least one halogen atom. The hydrocarbon group may have a branch, a ring, and / or an unsaturated bond. R ３２is a hydrocarbon group having 1 to 20 carbon atoms. The hydrocarbon group may have branching, rings, and / or unsaturated bonds. Furthermore, a heteroatom may be contained at any position within the hydrocarbon group. X is a divalent hydrocarbon group having 1 to 9 carbon atoms that may have direct bonds, branching, rings, and / or unsaturated bonds; or a divalent hydrocarbon group having 1 to 9 carbon atoms that may have branching, rings, and / or unsaturated bonds and is substituted with at least one halogen atom. As a compound represented by the above formula (2), R ３１ is a hydrogen atom or a hydrocarbon group having 1 to 5 carbon atoms, R ３２ Examples of compounds include those in which is a hydrocarbon group having 1 to 10 carbon atoms, and X is directly bonded or is an alkylene group having 3 or 8 carbon atoms. In addition, as a compound, R ３１ Acrylic acid ester or R, where is a hydrogen atom ３１ A methacrylate ester in which the group is a methyl group is preferred.

[0033] Specific examples of compounds represented by the above formula (2) include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, Nonyl methacrylate, Decyl methacrylate, Dodecyl methacrylate, Octadecyl methacrylate, Phenyl methacrylate, Toluyl methacrylate, Benzyl methacrylate, Methyl 5-hexenoate, Ethyl 5-hexenoate, N-propyl 5-hexenoate, I-propyl 5-hexenoate, N-butyl 5-hexenoate, I-butyl 5-hexenoate, T-butyl 5-hexenoate, Pentyl 5-hexenoate, Hexyl 5-hexenoate Syl, 5-cyclohexyl hexenoate, 5-octyl hexenoate, 5-2-ethylhexyl hexenoate, 5-nonyl hexenoate, 5-decyl hexenoate, 5-dodecyl hexenoate, 5-octadecyl hexenoate, 5-phenyl hexenoate, 5-toluyl hexenoate, 5-benzyl hexenoate, 10-methyl undecenoate, 10-ethyl undecenoate, 10-n-propyl undecenoate, 10-i-propyl undecenoate, 10-n-butyl undecenoate, 10-u Examples include i-butyl undecenoate, t-butyl undecenoate, pentyl undecenoate, hexyl undecenoate, cyclohexyl undecenoate, octyl undecenoate, 2-ethylhexyl undecenoate, nonyl undecenoate, decyl undecenoate, dodecyl undecenoate, octadecyl undecenoate, phenyl undecenoate, toluyl undecenoate, and benzyl undecenoate.Among these, examples of the compound represented by the above formula (2) include methyl acrylate, ethyl acrylate, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, methyl 5-hexenoate, ethyl 5-hexenoate, n-butyl 5-hexenoate, i-butyl 5-hexenoate, t-butyl 5-hexenoate, 2-ethylhexyl 5-hexenoate, methyl 10-undecenoate, ethyl 10-undecenoate, n-butyl 10-undecenoate, i-butyl 10-undecenoate, t-butyl 10-undecenoate, and 2-ethylhexyl 10-undecenoate. Particularly, n-butyl acrylate, i-butyl acrylate, t-butyl acrylate, methyl 5-hexenoate, ethyl 5-hexenoate, t-butyl 5-hexenoate, methyl 10-undecenoate, ethyl 10-undecenoate, and t-butyl 10-undecenoate are preferred. Note that the compound represented by the above formula (2) may be of one kind or a plurality of kinds may be used.

[0034] Further, the structural unit (B) may be obtained by copolymerizing at least one of the compounds represented by the following general formula (3) as a monomer. H ２ C═CR ４ -T ２ ... (3) [In formula (3), R ４ is a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 10 carbon atoms, or a hydrocarbon group having 1 to 10 carbon atoms substituted with at least one halogen atom, and T ２ is a carboxy group, an alkoxycarbonyl group having 2 to 20 carbon atoms substituted with one or more carboxy groups, a hydrocarbon group having 1 to 30 carbon atoms substituted with one or more carboxy groups, an alkoxy group having 1 to 20 carbon atoms substituted with one or more carboxy groups, an acyloxy group having 2 to 20 carbon atoms substituted with one or more carboxy groups, a substituted amino group having 1 to 12 carbon atoms substituted with one or more carboxy groups, or a substituted silyl group having 1 to 18 carbon atoms substituted with one or more carboxy groups. The hydrocarbon chain portion in the substituent may have a ring and / or an unsaturated bond and may have a hetero atom at any position within the hydrocarbon chain. ]

[0035] In formula (3), the carbon atoms of the hydrocarbon group are not included in the carbon count, while the carbon atoms of functional groups other than the carboxyl group are included. Furthermore, heteroatoms that can be present at any position in the hydrocarbon chain include halogen atoms (F, Cl, Br, and I) and divalent heteroatoms (O, NH, N(CH)). ３ ), Si(CH ３ ) ２ Si(CH ２ CH ３ ) ２ Si(CH ２ CH ２ CH ３ ) ２ Si(CH(CH ３ )CH ３ ) ２ , Si(OCH ２ CH ３ ) ２ SiPh ２ , Si(OH) ２ SiPhCH ３ Examples include the following. The substituted amino group may be a monosubstituted amino group or a disubstituted amino group. In the case of a disubstituted amino group, each substituent may be a hydrocarbon group having 1 to 12 carbon atoms, or a hydrocarbon group having 1 to 6 carbon atoms. The substituted silyl group may be a monosubstituted, disubstituted, or trisubstituted silyl group. In the case of disubstituted and trisubstituted silyl groups, each substituent may be a hydrocarbon group having 1 to 18 carbon atoms, or a hydrocarbon group having 1 to 6 carbon atoms. Among these, R ４ may be a hydrogen atom or a methyl group, T ２ This may be a carboxyl group or a hydrocarbon group having 1 to 10 carbon atoms that is substituted with at least one carboxyl group.

[0036] Specific examples of the compound represented by formula (3) above include (meth)acrylic acid, 5-hexenoic acid, 10-undecenoic acid, and the compounds exemplified as "non-limiting examples of preferred monomers from which structural unit (b-1) is derived" in paragraph 0033 of Japanese Patent Application Publication No. 2020-117712. Among these, structural unit (B) may be (meth)acrylic acid, 5-hexenoic acid, or 10-undecenoic acid, and the structural unit (B) may be single or multiple types, and the above monomer may be used individually or in combination of two or more types.

[0037] (3) Structural unit (C) Structural unit (C) is a structural unit having a carboxylic acid metal base. Structural unit (C) is the same as η ｍａｘ (t １ ) and η ｌｉｎ (t １ ) and η ｍａｘ (t １ )>η ｌｉｎ (t １ ), and as long as the above formula (α) or (β) is satisfied, it is not particularly limited, but it is preferably either the first or second embodiment shown below.

[0038] <First Embodiment> In the first embodiment, the structural unit (C) is a structural unit having a carboxylic acid metal base, wherein the carboxylic acid metal base is M, which has at least two metal atoms. １ and M ２ It contains M １ and M ２ The electronegativity of Polling is χ, respectively. Ｍ１ and χ Ｍ２ When this is the case, χ Ｍ１ -χ Ｍ２ This is a structural unit where χ is 0.06 or greater. Ｍ１ > χ Ｍ２ Here, the ionomer has M in the same molecular chain. １ and M ２ Even in embodiments that include both, M １ Molecular chains containing only M ２ It may also be in the form of a mixture with molecular chains containing only [the specified element]. If there are three or more metal atoms, the metal atom with the highest electronegativity is [the specified element]. １ And all other metal atoms are M２ If there are two or more metal atoms with the highest electronegativity, then one of the metal atoms is defined as M. １ Let's assume that. M ２ At least one of them is χ Ｍ１ -χ Ｍ２ It is sufficient if the value is ≥ 0.06. In this case, the most abundant M is... ２ ga χ Ｍ１ -χ Ｍ２ It may also satisfy ≥0.06. Furthermore, if there are four or more metal atoms, the metal atom with the highest electronegativity is the first M １ (M １－１ ), the metal atom with the second highest electronegativity is the second M １ (M １－２ ), and so on, divide the number of different types of metal atoms contained by 2, and round down the decimal part to get the number of metal atoms equal to M １ And the remaining metal atoms are M ２ When this is the case, χ Ｍ１ -χ Ｍ２ M that satisfies ≥ 0.06 １ and M ２ There should be at least one combination of χ. Ｍ１ -χ Ｍ２ M that satisfies ≥ 0.06 １ and M ２ There can be multiple combinations.

[0039] Carboxylic acid metal bases are thought to be involved in generating intermolecular bonds between polymer chains in ionsomers. Specifically, aggregates (ionic aggregates) are formed between the metal atom and carboxyl group of the carboxylic acid metal base, and these are thought to act as pseudo-crosslinking sites. In linear ionsomers, these aggregates affect the polymer chains, and if a rapid increase in viscosity occurs during elongation, strain hardening is thought to occur. The reason why the strain hardening of ionsomers having at least two metal atoms with a specific electronegativity difference was significantly higher than the strain hardening estimated from ionsomers with single metal atoms is thought to be as follows: Generally, the ionic bonding between two atoms becomes stronger as the difference in electronegativity between the two atoms increases. As a result of the affinity that develops between the two metal atoms due to the effect of ionic bonding, these two metal atoms come to be present in a single aggregate, and the formation of a double salt is expected. It is thought that the aggregate in which the double salt is formed interacts not only with the originally present metal atom and carboxyl group, but also between the two metal atoms, affecting the polymer chain. In other words, ionomers having at least two metal atoms with an electronegativity difference of a certain level or more exhibited significantly higher strain hardening properties than ionomers having at least two metal atoms with an electronegativity difference of less than a certain level, and even higher than the average value predicted from ionomers using each metal atom individually, because double salts were formed in the aggregate.

[0040] From the viewpoint of improving strain hardening properties, Ｍ１ -χ Ｍ２ It is preferably 0.06 to 1.84, more preferably 0.18 to 1.84, even more preferably 0.22 to 1.66, even more preferably 0.25 to 1.60, even more preferably 0.28 to 1.55, particularly preferably 0.30 to 1.50, and particularly more preferably 0.34 to 1.23. Also, χ Ｍ１ -χ Ｍ２ This may be 0.28 to 0.95, 0.28 to 0.98, 0.28 to 1.35, or 0.28 to 1.40.

[0041] χ Ｍ１It is preferably 1.00 or higher, more preferably 1.31 to 2.54, even more preferably 1.36 to 2.36, and particularly preferably 1.54 to 2.33. Specific M １ These include iron (1.83), cobalt (1.88), nickel (1.91), copper (1.90), molybdenum (2.16), technetium (1.9), ruthenium (2.2), rhodium (2.28), palladium (2.20), silver (1.93), tungsten (2.36), rhenium (1.9), osmium (2.2), iridium (Ir 2.20), platinum (2.28), gold (2.54), mercury (2.00), germanium (2.01), tin (1.96), antimony (2.05), lead (2.33), bismuth (2.02), and polonium. Examples include aluminum (2.0), astatine (2.2), zinc (1.65), gallium (1.81), cadmium (1.69), indium (1.78), thallium (1.62), aluminum (1.61), beryllium (1.57), magnesium (1.31), calcium (1.00), scandium (1.36), yttrium (1.22), titanium (1.54), zirconium (1.33), hafnium (1.3), vanadium (1.63), niobium (1.6), tantalum (1.5), chromium (1.66), and manganese (1.55). The numbers in parentheses represent electronegativity. Among these, from the viewpoint of ease of handling, it is preferable that at least one is selected from the group consisting of Fe, Co, Ni, Cu, Ag, Pb, Ti, V, Cr, Mn, and Zn, and more preferably that at least one is selected from the group consisting of Fe, Ag, Pb, and Zn. １ It may be one type or multiple types.

[0042] χ Ｍ２ χ may be 0.70 to 2.33, 0.79 to 1.93, 0.82 to 1.83, 0.89 to 1.65, or 0.93 to 1.65. However, χ Ｍ１ > χ Ｍ２ It shall satisfy the following conditions. Specific M ２ As for M １In addition to those exemplified above, lithium (0.98), sodium (0.93), potassium (0.82), rubidium (0.82), cesium (0.79), francium (0.7), strontium (0.95), barium (0.89), etc. can also be used. Among these, from the viewpoint of ease of handling, it is preferable to use at least one selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, and Zn, and more preferably at least one selected from the group consisting of Li, Na, K, Mg, Ca, and Zn. ２ It may be one type or multiple types.

[0043] From the perspective of ease of handling, M １ is selected from the group consisting of Fe, Co, Ni, Cu, Ag, and Pb, M ２ is selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba and Zn, or M １ The group is selected from Ti, V, Cr, Mn, and Zn, and M ２ It is preferable that the element is selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, and Ba. Furthermore, M １ The group is selected from Fe, Ag, and Pb, M ２ is selected from the group consisting of Li, Na, K, Mg, Ca, and Zn, or M １ is Zn, M ２ It is more preferable that the element is selected from the group consisting of Li, Na, K, Mg, and Ca.

[0044] <Second Embodiment> In the second embodiment, the structural unit (C) has a carboxylic acid metal base, and the carboxylic acid metal base is a metal atom M having a Pauling electronegativity χ of 1.83 to 2.54. ３ It is a structural unit containing at least one of the following. When using an ionomer with a substantially linear structure containing at least one metal atom with a Pauling electronegativity χ of 1.83 to 2.54, its λmax can be made higher than that of conventional substantially linear ionomers.

[0045] The aforementioned pseudo-bridge point is M３ It is thought that aggregates are also formed between the carboxyl group and the carboxyl group. Furthermore, if these aggregates are strong, it is considered desirable for the development of strain hardening properties. The strength of these aggregates depends on the oxygen atom of the carboxyl group and M ３ It is presumed that this can be estimated from the electronegativity of each atom. For example, Non-Patent Literature 6 uses Pauling's electronegativity χ to estimate the bonding mode between two atoms using the difference in electronegativity (Δχ) and the average (χ). 平均 This is organized as follows. According to this finding, the bonding mode between a metal atom and an oxygen atom is thought to be ionic when the χ value of the metal atom is less than 1.83, while it is covalent when the χ value is between 1.83 and 2.54. In general, covalent bonds are stronger than ionic bonds. The relationship between the bonding mode between two atoms and electronegativity is also reported in Non-Patent Document 7.

[0046] In other words, as a carboxylic acid metal base, M has an electronegativity χ of 1.83 to 2.54. ３ If included, the bonds between the polymers described above exhibit covalent bonding, which strengthens the aggregate and is thought to contribute to the development of strain hardening. In this case, oxygen atoms (χ: 3.44) and M ３ The difference in electronegativity Δχ between the two is less than 1.61 and less than 1.7, which is consistent with Non-Patent Document 7. ３ electronegativity χ Ｍ３ χ may be 1.83 to 2.36, or 1.83 to 2.33. Also, since it may be better not to have a completely covalent bond, Ｍ３ It may be 1.83 to 2.33, 1.83 to 2.30, 1.83 to 2.20, 1.85 to 2.10, 1.88 to 2.03, or 1.83 to 1.93.

[0047] Specific M ３Examples include iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), molybdenum (Mo), technetium (Tc), ruthenium (Ru), rhodium (Rh), palladium (Pd), silver (Ag), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), gold (Au), mercury (Hg), germanium (Ge), tin (Sn), antimony (Sb), lead (Pb), bismuth (Bi), polonium (Po), and astatine (At). Among these, from the viewpoint of ease of handling, it is more preferable to have at least one selected from the group consisting of Fe, Co, Cu, Ni, Ge, Tc, Mo, Rh, Pd, Ag, Sn, Sb, Re, Os, Ir, Pt, Hg, Pb, Bi, and Po, with Fe, Ag, and Pb being particularly preferred. ３ This may be one type or multiple types, but in the case of multiple types, the difference in electronegativity between each metal atom may be less than 0.06.

[0048] <Structure of structural unit (C)> The structural unit (C) may also be represented by the following general formula (4): -(CH ２ CR １ T １ )--Equation (4) [In Equation (4), R １ represents a hydrogen atom; a halogen atom; a carboxyl group; a C1-C10 hydrocarbon group substituted with at least one halogen atom; a C1-C10 hydrocarbon group substituted with at least one carboxyl group; or a C1-C10 hydrocarbon group. In the first embodiment, T １ The above M １ Or M ２ A carboxylic acid metal base having the M １ Or M ２ It represents a hydrocarbon group having 1 to 30 carbon atoms, an alkoxycarbonyl group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 2 to 20 carbon atoms, a substituted amino group having 1 to 12 carbon atoms, or a substituted silyl group having 1 to 18 carbon atoms, which is substituted with at least one carboxylate metal base having . In a second embodiment, T １ The above M ３ A carboxylic acid metal base having the M３ This represents a hydrocarbon group having 1 to 30 carbon atoms, an alkoxycarbonyl group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 2 to 20 carbon atoms, a substituted amino group having 1 to 12 carbon atoms, or a substituted silyl group having 1 to 18 carbon atoms, all of which are substituted with at least one carboxylate metal base having [the specified compound]. The hydrocarbon chain portion in the substituent may have a ring and / or an unsaturated bond, and may have a heteroatom at any position within the hydrocarbon chain.

[0049] In formula (4), the carbon atoms of the hydrocarbon group are not included in the carbon count of the carboxyl group and the carboxylate metal base, while the carbon atoms of functional groups other than the carboxyl group and the carboxylate metal base are included in the carbon count. Furthermore, heteroatoms that can be located at any position in the hydrocarbon chain include halogen atoms (F, Cl, Br, and I) and divalent heteroatoms (O, NH, N(CH)). ３ ), Si(CH ３ ) ２ Si(CH ２ CH ３ ) ２ Si(CH ２ CH ２ CH ３ ) ２ Si(CH(CH ３ )CH ３ ) ２ , Si(OCH ２ CH ３ ) ２ SiPh ２ , Si(OH) ２ SiPhCH ３ Examples include the following. The substituted amino group may be a monosubstituted amino group or a disubstituted amino group. In the case of a disubstituted amino group, each substituent is a hydrocarbon group having 1 to 12 carbon atoms, preferably a hydrocarbon group having 1 to 6 carbon atoms. The substituted silyl group may be a monosubstituted, disubstituted, or trisubstituted silyl group. In the case of disubstituted and trisubstituted silyl groups, each substituent is a hydrocarbon group having 1 to 18 carbon atoms, preferably a hydrocarbon group having 1 to 6 carbon atoms.

[0050] R １Examples of halogen atoms in this include fluorine, chlorine, bromine, etc., and chlorine may also be used. １ The hydrocarbon group having 1 to 10 carbon atoms in the compound may be a branched, cyclic, and / or unsaturated hydrocarbon group, or an alkyl group having 1 to 10 carbon atoms. Specifically, methyl group, ethyl group, 1-propyl group, 1-butyl group, 1-pentyl group, 1-hexyl group, 1-heptyl group, 1-octyl group, 1-nonyl group, 1-decyl group, t-butyl group, i-propyl group, 1,1-dimethylpropyl group, 1,1,2-trimethylpropyl group, 1,1-diethylpropyl group, i-butyl group, 1,1-dimethylbutyl group, 2-pentyl group, 3-pentyl group, 2-hexyl Examples include the groups 3-hexyl, 2-ethylhexyl, 2-heptyl, 3-heptyl, 4-heptyl, 2-propylheptyl, 2-octyl, 3-nonyl, cyclopropyl, cyclobutyl, cyclopentyl, methylcyclopentyl, cyclohexyl, methylcyclohexyl, cycloheptyl, cyclooctyl, 1-adamantyl, and 2-adamantyl. １ Examples of C1-C10 hydrocarbon groups substituted with at least one halogen atom include groups in which at least one hydrogen atom in the aforementioned C1-C10 hydrocarbon group is substituted with the aforementioned halogen atom. Specifically, a trifluoromethyl group is an example. １ Examples of hydrocarbon groups having 1 to 10 carbon atoms that are substituted with at least one carboxyl group include groups in which at least one hydrogen atom in the aforementioned hydrocarbon groups having 1 to 10 carbon atoms is substituted with a carboxyl group. Among these, R １ This may be a hydrogen atom or a methyl group.

[0051] In the first embodiment, T １ M in １ Or M ２ A carboxylate metal base having, for example, the carboxyl group in structural unit (B) is M １ or M ２Neutralization with a compound containing; in a copolymer of ionomer raw materials, after hydrolysis or thermal decomposition of the ester group, or while hydrolysis or thermal decomposition, M １ or M ２ It may also be produced by reacting it with a compound containing . In this way, it can be obtained by converting the ester group portion in the copolymer of the raw materials into a carboxylate metal base. １ or M ２ The compound containing may be one type or multiple types. Similarly in the second embodiment, T １ M in ３ A carboxylic acid metal base having M can be produced. ３ The compound containing may be one type or multiple types.

[0052] T １ Each substituent in formula (3) above relates to structural unit (B) ２ It can be obtained by converting the carboxyl group inside to a carboxylate metal base using the aforementioned procedure. １ M in １ Or M ２ A carboxylic acid metal base having T １ M in ３ Carboxylate metal bases having -CO in formula (2) ２ (R ３２ ) can be obtained by converting the group to a carboxylic acid metal base using the aforementioned procedure. Similarly, T １ M in １ Or M ２ Having or T １ M in ３ The hydrocarbon group, the alkoxycarbonyl group, the alkoxy group, the acyloxy group, the substituted amino group, or the substituted silyl group having at least one carboxylate metal base can be obtained by converting the ester group corresponding to the carboxylate metal base to the carboxylate metal base in the above-described operation. In the first embodiment, T １ M １ Or M ２A carboxylic acid metal base or M having １ Or M ２ A hydrocarbon group having 1 to 30 carbon atoms substituted with at least one carboxylic acid metal base having M １ Or M ２ A carboxylic acid metal base or M having １ Or M ２ A hydrocarbon group having 1 to 10 carbon atoms substituted with at least one carboxylic acid metal base having M １ Or M ２ A carboxylic acid metal base or M having １ Or M ２ It may be a C3 or C8 hydrocarbon group substituted with at least one carboxylic acid metal base having the following properties. In a second embodiment, T １ M ３ A carboxylic acid metal base or M having ３ A hydrocarbon group having 1 to 30 carbon atoms substituted with at least one carboxylic acid metal base having M ３ A carboxylic acid metal base or M having ３ A hydrocarbon group having 1 to 10 carbon atoms substituted with at least one carboxylic acid metal base having M ３ A carboxylic acid metal base or M having ３ It may be a C3 or C8 hydrocarbon group substituted with at least one carboxylic acid metal base having the following properties.

[0053] In the first embodiment, in equation (4), R １ may be a hydrogen atom or a methyl group, T １ M １ Or M ２ A carboxylic acid metal base or M having １ Or M ２ It may be a C3 or C8 hydrocarbon group substituted with at least one carboxylic acid metal base having . In the second embodiment, in formula (4), R １ may be a hydrogen atom or a methyl group, T １ M ３ A carboxylic acid metal base or M having ３It may be a C3 or C8 hydrocarbon group substituted with at least one carboxylic acid metal base having the following properties.

[0054] In the first embodiment, the structural unit (C) is M １ and M ２ It contains at least two structural units, and may contain three or more structural units. Furthermore, structural unit (C) has a portion of the carboxyl group or dicarboxylic anhydride group of structural unit (B) as M １ and M ２ It may be modified by converting it into a metal salt containing, or it may not be a modification of structural unit (B). In the second embodiment, structural unit (C) is M ３ It contains at least one structural unit including, and may contain two or more structural units. Furthermore, structural unit (C) has a part of the carboxyl group or dicarboxylic anhydride group of structural unit (B) M ３ It may be a modified form that has been converted to a metal salt containing the same substance, or it may not be a modified form of structural unit (B).

[0055] (4) Other structural unit ionomers may include structural units other than structural units (A) to (C). Examples of other structural units (D) include acyclic monomers, cyclic monomers, etc. Examples of acyclic monomers include the monomers disclosed in paragraphs 0026 to 0028 of Japanese Patent Application Publication No. 2023-143881. In general formula (1) of Japanese Patent Application Publication No. 2023-143881, T １ ~T ４ The monomers do not include any monomers that contain an ester group having 2 to 20 carbon atoms. Examples of cyclic monomers include those disclosed in paragraphs 0030 to 0031 of Japanese Patent Application Publication No. 2023-143881.

[0056] (5) Amount of Each Structural Unit The amount of structural units in the ionomer (amount of structural units) is explained below. Structural units (A) derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms; structural units (B) having at least one selected from the group consisting of carboxyl groups and dicarboxylic acid anhydride groups; and structural units (C) having a carboxylic acid metal base, the smallest repeating structural unit in each is defined as one structural unit in the ionomer. The amount of structural units is expressed in mol%, representing the ratio of each structural unit when the total amount of structural units in the ionomer is set to 100 mol%. The sum of the amount of structural units of structural units (A) of the ionomer, and the sum of the amount of structural units of structural units (B) and (C) is equivalent to the sum of the amount of structural units of structural units (A) of the raw material copolymer, and the sum of the amount of structural units of structural units (B) and structural units having an alkoxycarbonyl group. This is because, in the procedure for producing an ionomer from a raw material copolymer, there are no factors that alter the structural units other than modifying a portion of structural unit (B) to create structural unit (C), as described above. Therefore, the amount of structural units of structural unit (A) of the raw material copolymer is the amount of structural units of structural unit (A) of the ionomer, and the sum of the amount of structural units of structural unit (B) and structural units having alkoxycarbonyl groups of the raw material copolymer is the sum of the amount of structural units of structural units (B) and (C) of the ionomer. Furthermore, if a portion of structural unit (B) of the raw material copolymer is modified to form structural unit (C), the amount of structural units of structural units (B) and (C) of the ionomer may be calculated by taking the portion modified into structural unit (C) as the amount of structural unit (C), and subtracting the amount of structural unit (C) from the amount of structural unit (B) of structural unit (B) of the raw material copolymer as the amount of structural unit (B) of structural unit (C).

[0057] The amount of structural unit (A) relative to the sum of the mol content of structural unit (A), structural unit (B), and structural unit (C) (100 mol%) is preferably 80.00 to 99.99 mol%, more preferably 85.00 to 99.95 mol%, more preferably 90.00 to 99.95 mol%, even more preferably 90.00 to 99.90 mol%, even more preferably 92.00 to 99.50 mol%, even more preferably 94.00 to 99.00 mol%, even more preferably 95.00 to 98.50 mol%, and particularly preferably 95.00 to 96.90 mol%. Furthermore, the structural unit amount of structural unit (A) can also be 92.00–99.95 mol%, 94.00–99.95 mol%, 95.00–99.95 mol%, 85.00–96.90 mol%, 90.00–96.90 mol%, 92.00–96.90 mol%, 94.00–96.90 mol%, 90.00–96.50 mol%, 90.00–96.00 mol%, or 90.00–95.50 mol%. If the structural unit amount of structural unit (A) is 80.00 mol% or more, it is considered that the ionomer is likely to obtain sufficient mechanical properties, and if it is 99.99 mol% or less, it is considered that the ionomer is likely to obtain sufficient strain hardening properties.

[0058] The sum of the structural unit amounts (mol%) of structural unit (B) and structural unit (C) relative to the total mol content (100 mol%) of structural unit (A), structural unit (B), and structural unit (C) is preferably 0.01 to 20.00 mol%, preferably 0.05 to 15.00 mol%, more preferably 0.05 to 10.00 mol%, even more preferably 0.10 to 10.00 mol%, even more preferably 0.50 to 8.00 mol%, even more preferably 1.00 to 6.00 mol%, even more preferably 1.50 to 5.00 mol%, and particularly preferably 3.10 to 5.00 mol%. Furthermore, the sum of the structural unit amounts of structural unit (B) and structural unit (C) can be 0.05–8.00 mol%, 0.05–6.00 mol%, 0.05–5.00 mol%, 3.10–15.00 mol%, 3.10–10.00 mol%, 3.10–8.00 mol%, 3.10–6.00 mol%, 3.50–10.00 mol%, 4.00–10.00 mol%, or 4.50–10.00%. If the sum of the structural unit amounts of structural unit (B) and structural unit (C) is 0.01 mol% or more, the ionomer is likely to exhibit sufficient strain hardening properties. Also, if it is 20.00 mol% or less, the ionomer is likely to exhibit sufficient mechanical properties.

[0059] The sum of the structural unit quantity of structural unit (A) and the structural unit quantities of structural unit (B) and structural unit (C) can be any combination selected such that (structural unit quantity of structural unit (A) + (structural unit quantity of structural unit (B) + structural unit quantity of structural unit (C))) = 100 mol% in each of the above combinations.

[0060] The content of structural unit (C) (degree of neutralization) in mol% refers to the ratio (mol%) of the mol content of structural unit (C) to the total mol content of structural unit (B) and structural unit (C) (100 mol%), and is also called the degree of neutralization. The degree of neutralization of the ionomer is preferably 20 to 70 mol%, more preferably 22 to 68 mol%, even more preferably 24 to 66 mol%, even more preferably 25 to 65 mol%, and even more preferably 26 to 65 mol%.

[0061] When the degree of neutralization of the ionomer is high, the degree of strain hardening of the ionomer increases, but the shear viscosity of the ionomer tends to increase. On the other hand, when the degree of neutralization is low, an ionomer with low shear viscosity and high fluidity is obtained, but the strain hardening properties tend to be low. When the degree of neutralization of the ionomer is 20 mol% or higher, sufficient strain hardening properties are easily obtained, and sufficient moldability is considered to be achieved. When the degree of neutralization of the ionomer is 70 mol% or lower, fluidity is maintained while having a high degree of strain hardening, and sufficient moldability is considered to be easily obtained.

[0062] In the first embodiment, the ionomer is M １ and M ２ It may also be a copolymer containing a carboxylic acid metal base having M １ Ionomer (1) containing a carboxylic acid metal base and M ２It may also be a mixture of ionomers (2) containing a carboxylic acid metal base. In the latter case, the degree of neutralization is an average value calculated by summing the values ​​obtained by multiplying the degree of neutralization of each constituent ionomer by its blending ratio (by weight) when the raw material copolymer is the same. When the ionomer is a mixture of ionomers (1) and (2), the degree of neutralization of ionomers (1) and (2) may be 1 to 99 mol%, 5 to 95 mol%, 10 to 90 mol%, or 18 to 85 mol%, respectively, when the total mol content of structural unit (B) and structural unit (C) in each ionomer is taken as 100 mol%. The ionomer may also be a mixture of three or more ionomers, and the degree of neutralization of each ionomer may be the same as in the two examples above.

[0063] (6) １３ The methyl branching number, ethyl branching number, and butyl branching number ionomers calculated by C-NMR are: １３ The number of methyl branches calculated by C-NMR is 50 or less per 1,000 carbon atoms, or the sum of the number of ethyl branches and butyl branches is less than 4.2 per 1,000 carbon atoms. The number of methyl branches, ethyl branches, and butyl branches are inhibitors of crystallization in the structure of the ionomer, and the smaller the number of these branches, the better the mechanical properties of the copolymer.

[0064] Includes structural unit (C), １３ Ionomers whose sum of methyl branching numbers or ethyl branching numbers and butyl branching numbers, calculated by C-NMR, falls within the above range, exhibit excellent mechanical strength and transparency, as well as high strain hardening resistance and excellent moldability. Ionomers are, １３ Preferably, the number of methyl branches calculated by C-NMR is 50 or less per 1,000 carbon atoms, and the sum of the number of ethyl branches and butyl branches is less than 4.2 per 1,000 carbon atoms.

[0065] In order to increase the elastic modulus of the ionomer and obtain sufficient mechanical properties, １３The number of methyl branches calculated by C-NMR is preferably 50 or less, more preferably 5.0 or less, still more preferably 4.0 or less, even more preferably 3.0 or less, and particularly preferably 2.5 or less per 1,000 carbon atoms. The lower limit of the number of methyl branches is not particularly limited, and the smaller the better.

[0066] From the viewpoint of increasing the elastic modulus of the ionomer and obtaining sufficient mechanical properties, １３ The total of the number of ethyl branches and the number of butyl branches calculated by C-NMR is preferably less than 4.2, more preferably 4.0 or less, still more preferably 3.8 or less, even more preferably 3.5 or less, still more preferably 3.0 or less, even more preferably 2.5 or less, further preferably 2.0 or less, still further preferably 1.5 or less, and particularly preferably 1.0 or less per 1,000 carbon atoms. The lower limit of the total of the number of ethyl branches and the number of butyl branches is not particularly limited, and the smaller the better. Also, the upper limit of the number of ethyl branches may be less than 4.2, may be 4.0 or less, may be 3.5 or less, may be 3.0 or less, may be 2.0 or less, may be 1.0 or less, or may be 0.5 or less per 1,000 carbon atoms. The lower limit of the number of ethyl branches is not particularly limited, and the smaller the better. Furthermore, the upper limit of the number of butyl branches may be less than 4.2, may be 4.0 or less, may be 3.0 or less, may be 2.0 or less, may be 1.0 or less, or may be 0.5 or less per 1,000 carbon atoms. The lower limit of the number of butyl branches is not particularly limited, and the smaller the better.

[0067] The sum of the methyl branching number, ethyl branching number, and butyl branching number in the ionomer is equivalent to that of the raw material copolymer. This is because there are no factors that cause variations in the branching number during the process of producing the ionomer from the raw material copolymer. Therefore, if the sum of the methyl branching number, ethyl branching number, and butyl branching number of the raw material copolymer is within the above range, the sum of the methyl branching number, ethyl branching number, and butyl branching number of the ionomer will also be similar.

[0068] (7) Method for measuring the amount of structural units of each structural unit in the ionomer and the copolymer of raw materials, as well as the number of methyl branches, ethyl branches and butyl branches. １３ This is determined by C-NMR. １３ Details of the 13C-NMR measurement method and measuring apparatus are as described in the examples. The amount of structural unit (B) may be determined from the ratio of structural unit (C) obtained by IR spectroscopy, as described later, based on the amount measured for the copolymer of the raw materials using the method described in the examples.

[0069] obtained １３ In 13C-NMR spectroscopy, the amount of each structural unit and the number of branches in the ionomer and the raw material copolymer can be analyzed by identifying the signals specific to each structural unit, its originating monomer, or branching, and comparing their intensities. The location of the signals specific to each structural unit, its originating monomer, or branching can be determined by referring to known data or by independently identifying them depending on the sample. Such analytical methods are generally possible for those skilled in the art.

[0070] The sum of the structural unit amounts (mol content) of structural unit (B) and structural unit (C) was calculated as described in the example. In the example, the ionomer is produced by starting with the raw material copolymer, ethylene / t-butyl acrylate copolymer, and modifying all structural units derived from t-butyl acrylate in the copolymer to either structural unit (B) or structural unit (C). That is, the amount of structural units derived from t-butyl acrylate in the raw material copolymer is the sum of the structural unit amounts of structural unit (B) and structural unit (C). The amount of structural units derived from t-butyl acrylate in the raw material copolymer is calculated from the signal intensity of the quaternary carbon signal of the t-butyl group. The structural unit amount of structural unit (A) is obtained by subtracting the amount of structural units derived from t-butyl acrylate in the raw material copolymer from 100 mol%.

[0071] (8) Weight-average molecular weight (Mw) and molecular weight distribution (Mw / Mn) The weight-average molecular weight (Mw) of the ionomer and the copolymer of raw materials has a lower limit of 1,000 or more, may be 6,000 or more, may be 10,000 or more, may be 15,000 or more, and may be 20,000 or more. The upper limit is usually 2,000,000 or less, may be 1,500,000 or less, may be 1,000,000 or less, may be 800,000 or less, and may be 100,000 or less. If Mw is 1,000 or more, the physical properties of the ionomer, such as mechanical strength and impact resistance, are sufficient, and if Mw is 2,000,000 or less, the melt viscosity of the copolymer is appropriate, and it is considered that there is little effect on the molding process of the copolymer.

[0072] The ratio of Mw to number-average molecular weight (Mn) (Mw / Mn) of the ionomer and the copolymer of the raw materials is usually between 1.5 and 4.0, but may be between 1.6 and 3.5, between 1.7 and 2.7, between 1.9 and 2.4, or between 1.9 and 2.3. If Mw / Mn is 1.5 or higher, sufficient processability, including molding of the ionomer, is easily obtained, and if it is 4.0 or lower, sufficient mechanical properties are easily obtained. The Mw and Mn of the ionomer are equivalent to those of the copolymer of the raw materials. This is because the polymer chains are not cleaved in the procedure for producing the ionomer from the copolymer of the raw materials. Therefore, if the Mw and Mn of the copolymer of the raw materials are within the above range, the Mw and Mn of the ionomer are also similar. As a method to actively suppress polymer chain cleavage, additives can be added in any step of the ionomer production process, as long as it does not significantly impair the effects of the present invention. Examples of additives include general antioxidants, which may be phenolic, amine, phosphorus, and sulfur-based antioxidants.

[0073] The above Mw is determined by gel permeation chromatography (GPC). Furthermore, the molecular weight distribution parameter (Mw / Mn) is calculated by determining Mn using GPC, and then calculating the ratio of Mw to Mn, Mw / Mn. Details of the GPC measurement method and apparatus are described in the examples.

[0074] (9) Molecular structure of the ionomer The molecular chain end of the ionomer may be structural unit (A); structural unit (B); or structural unit (C).

[0075] Ionomers include random copolymers, block copolymers, and graft copolymers of structural unit (A), structural unit (B), and structural unit (C). Among these, random copolymers that can contain a large amount of structural unit (B) are also acceptable.

[0076] An example of the molecular structure of a typical ternary copolymer (1) is shown below. A random copolymer is a copolymer in which, as shown in the molecular structure example (1) below, the probability of structural units (A), (B), and (C) being found at any given position in a molecular chain is independent of the type of adjacent structural units.

[0077] As shown below, in the molecular structure example (1) of the copolymer, structural unit (A), structural unit (B), and structural unit (C) form a random copolymer.

[0078] Ionomers are preferably linear in structure, and from this viewpoint, it is preferable that they be produced in the presence of a transition metal catalyst. It is known that the molecular structure of copolymers differs depending on the production method, such as polymerization by high-pressure radical polymerization or polymerization using a metal catalyst. This difference in molecular structure can be controlled by selecting the production method. One example of a difference in molecular structure is the difference in the number of branches. In polymerization by high-pressure radical polymerization, even in ethylene homopolymerization, many ethyl and butyl branches are generated, and this number is known to increase further in copolymerization of ethylene with a comonomer having a polar group (Macromolecules, 1997, 30, pp. 246-256).

[0079] Another example of a difference in molecular structure is that, as described in Japanese Patent Publication No. 2010-150532, the molecular structure can also be estimated by the complex modulus measured with a rotational rheometer. This complex modulus may be the value for the copolymer of the raw materials of the ionomer. This is because, if the ionomer is not directly produced in a single polymerization step, it will go through a process of converting the raw material copolymer to the ionomer, but this conversion process does not involve a reaction that affects the molecular structure of the polymer. An example of a reaction included in this conversion process is a reaction to change the side chains of the polymer, such as ester deprotection or neutralization with a metal salt, and not a reaction that dissociates and recombines the carbon-carbon bond of the main chain.

[0080] (10) ηｍａｘ (t １ ) and η ｌｉｎ (t １ In relation to the relationship between ionomers, the maximum extensional viscosity after strain hardening is shown in a log-log plot of extensional viscosity η(t) (unit: Pa·seconds) and extension time t (unit: seconds), obtained by uniaxial extensional viscosity measurement at 140°C and extensional strain rate of 0.2 [1 / second]. ｍａｘ (t １ ), the time t at that time １ η is the approximate linear relationship of extensional viscosity before strain hardening. ｌｉｎ When (t) is the case, η ｍａｘ (t １ ) and time t １ Extensional viscosity η on the approximate straight line in the above case ｌｉｎ (t １ ) and η ｍａｘ (t １ )>η ｌｉｎ (t １ ), and satisfying either equation (α) or (β) below. η ｍａｘ (t １ ) and η ｌｉｎ (t １ By satisfying the above relationship, it becomes possible to increase the strain-hardening properties of the ionomer and improve its moldability. ｍａｘ (t １ ) > 1.9η ｌｉｎ (t １ ) １．１ Equation (α) η ｍａｘ (t １ ) ≥ 1.9η ｌｉｎ (t １ ) ０．７ Equation (β) Here, the approximate linear relationship of extensional viscosity before strain hardening is: η ｌｉｎ (t) is the tangent line with the smallest slope among the tangent lines to the curve of the log-log plot within the range of extension time t corresponding to a strain amount of 0.2 to 1.0 (however, the slope is 0 or a positive value). Also, η ｍａｘ (t １ ) and η ｌｉｎ (t １ The unit of ) is MPa·second. Equation (α) is η ｍａｘ (t １ ) > 2.5η ｌｉｎ (t １ ) １．１It is preferable that the following conditions be met: ｍａｘ (t １ ) > 2.8η ｌｉｎ (t １ ) １．１ It is more preferable that the following conditions be met: ｍａｘ (t １ ) > 3.0η ｌｉｎ (t １ ) １．１ It is even more preferable that the following conditions be met: ｍａｘ (t １ ) > 3.5η ｌｉｎ (t １ ) １．１ It is even more preferable that the following conditions be met: ｍａｘ (t １ ) > 4.0η ｌｉｎ (t １ ) １．１ It is particularly preferable that the following conditions be met. Equation (β) is given by η ｍａｘ (t １ ) ≥ 2.0η ｌｉｎ (t １ ) ０．７ It is preferable that this be the case.

[0081] Figure 3 shows a log-log plot of the extensional viscosity η(t) and extension time t obtained by uniaxial extensional viscosity measurement at 140°C and extensional strain rate of 0.2 [1 / sec] for the ionomer of Example 4. Figure 3 shows the approximate straight line of extensional viscosity before strain hardening: η ｌｉｎ An example of how to determine (t) is shown. In Figure 3, the ionomer of Example 4 is t = t １ The test specimen fractured, therefore the extensional viscosity η(t) is given by t = t １ It is maximized at (η) ｍａｘ (t １ )). η ｌｉｎ (t １ ) is t = t １ η at that time ｌｉｎ This is the value of (t).

[0082] Figure 4 shows the ionomers of the examples and comparative examples, η ｍａｘ (t １ ) and η ｌｉｎ (t １ This is a graph showing the relationship between ). Equation (α) is given by η for the measurement points of Comparative Examples 1 to 10 in Figure 4. ｍａｘ (t １The straight line connecting the upper ends of ) is such that, with x and y as variables, η ｍａｘ (t １ ) = y × η ｌｉｎ (t １ ) ｘ It is assumed that the equation is represented by and is based on the approximate linear equation obtained by the least squares method. Equation (α) is intended to exclude the ionomer of the comparative example. Similarly, equation (β) is given for the measurement points of Examples 1 to 12 in Figure 4, η ｍａｘ (t １ The straight line connecting the lower ends of ) is such that, with x and y as variables, η ｍａｘ (t １ ) = y × η Ｌｉｎ (t １ ) ｘ It is assumed to be represented by and is based on an approximate linear equation obtained by the least squares method. Equation (β) is the most restrictive condition that the ionomers of Examples 1-18 and 20 satisfy. 0.1 ≤ η ｌｉｎ (t １ ), and also satisfy equation (β), where 0.1 ≤ η ｌｉｎ (t １ ) ≤ 7.0, and also satisfy equation (β).

[0083] Ionomers are 0.01 ≤ η ｌｉｎ (t １ ) or 0.1 ≤ η ｌｉｎ (t １ The equation (α) may be satisfied within the range of ). Also, the ionomer is 0.01 ≤ η ｌｉｎ (t １ ) ≤ 1.0 or 0.1 ≤ η ｌｉｎ (t １ The equation (α) may be satisfied in the range ) ≤ 1.0. ｌｉｎ (t １ Within the range of ), equation (α): η ｍａｘ (t １ ) > 1.9η ｌｉｎ (t １ ) １．１ It is sufficient that the following conditions are met: ｍａｘ (t １ ) > 2.5η ｌｉｎ (t １ ) １．１ It is sufficient that the following conditions are met: ｍａｘ (t １ ) > 2.8ηｌｉｎ (t １ ) １．１ It is sufficient that the following conditions are met: ｍａｘ (t １ ) > 3.0η ｌｉｎ (t １ ) １．１ It is sufficient that the following conditions are met: ｍａｘ (t １ ) > 3.5η ｌｉｎ (t １ ) １．１ It is sufficient that the following conditions are met: ｍａｘ (t １ ) > 4.0η ｌｉｎ (t １ ) １．１ It may also satisfy the following conditions: Furthermore, the ionomer is 0.01 ≤ η ｌｉｎ (t １ Any of the above equations (α) may be satisfied within the range of < 0.1.

[0084] Furthermore, the ionomer is 0.01 ≤ η ｌｉｎ (t １ For ) ≤ 1.0, equation (α) is satisfied, and 1.0 < η ｌｉｎ (t １ For ) ≤ 7.0, equation (β) must be satisfied, and 0.01 ≤ η ｌｉｎ (t １ For ) ≤ 0.1, equation (α) is satisfied, and 0.1 < η ｌｉｎ (t １ For ) ≤ 7.0, equation (β) may also be satisfied. In particular, for ionomers, 0.01 ≤ η ｌｉｎ (t １ ) ≤ 1.0 or 0.01 ≤ η ｌｉｎ (t １ ) < 0.1, equation (α): η ｍａｘ (t １ ) > 2.5η ｌｉｎ (t １ ) １．１ It is more preferable that the following conditions be met: ｍａｘ (t １ ) > 2.8η ｌｉｎ (t １ ) １．１ It is even more preferable that the following conditions be met: ｍａｘ (t １ ) > 3.0η ｌｉｎ (t １ )１．１ It is even more preferable that the following conditions be met: ｍａｘ (t １ ) > 3.5η ｌｉｎ (t １ ) １．１ It is even more preferable that the following conditions be met: ｍａｘ (t １ ) > 4.0η ｌｉｎ (t １ ) １．１ It is particularly preferable that the following conditions be met. Also, the ionomer is 0.01 ≤ η ｌｉｎ (t １ ) ≤ 1.0 or 0.1 ≤ η ｌｉｎ (t １ ) ≤ 1.0, and equation (β) may also be satisfied.

[0085] Equation (β) is η ｍａｘ (t １ ) ≥ 1.9η ｌｉｎ (t １ ) ０．７ It is fine if it is η ｍａｘ (t １ ) ≥ 2.0η ｌｉｎ (t １ ) ０．７ This may also be the case. Any of these formulas (β) can be combined with each of the formulas (α) disclosed herein. The ionomer is 0.1 ≤ η ｌｉｎ (t １ ) ≤ 7.0 or 1.0 < η ｌｉｎ (t １ Any of these equations (β) may be satisfied within the range of ) ≤ 7.0.

[0086] In any combination of formulas (α) and (β) disclosed herein, the ionomer has an η below the intersection of formulas (α) and (β). ｌｉｎ (t １ ) satisfies equation (α), and η beyond the intersection ｌｉｎ (t １ ) may satisfy formula (β). Furthermore, in any combination of formula (α) and formula (β) disclosed herein, the ionomer may satisfy both formula (α) and formula (β), satisfy only formula (α), or satisfy only formula (β).

[0087] (11) The absolute value G of the complex modulus of elasticity ＊ = Phase angle δ at 0.1 MPa. From the viewpoint of increasing strain hardening properties and improving moldability, the ionomer has a complex modulus of elasticity of G measured with a rotary rheometer. ＊ = The phase angle δ at 0.1 MPa is preferably 50 to 75 degrees, more preferably 50 to 70 degrees, even more preferably 50 to 65 degrees, even more preferably 50 to 60 degrees, and particularly preferably 51 to 57 degrees. More specifically, the above phase angle δ (G ＊ When the pressure (=0.1 MPa) is 50 degrees or higher, the molecular structure of the ionomer is linear, either completely free of long-chain branching or containing a small amount of long-chain branching that does not affect its mechanical strength.

[0088] The above phase angle δ is influenced by both the molecular weight distribution and long-chain branching. However, for ionomers where Mw / Mn ≤ 4.0, more preferably Mw / Mn ≤ 3.0, it can serve as an indicator of the amount of long-chain branching, and the more long-chain branching there is in the molecular structure, the higher δ(G) ＊ The value (=0.1 MPa) will be smaller. Furthermore, if the Mw / Mn of the copolymer is 1.5 or higher, the above phase angle δ (G) will be smaller even if the molecular structure does not contain long-chain branching. ＊ The value (=0.1 MPa) will never exceed 75 degrees. Details of the measurement method and measuring apparatus for determining the above phase angle δ are as described in the examples.

[0089] The method for producing the ionomer does not alter the structure of the ionomer's main chain, but the phase angle δ may decrease due to an increase in pseudo-crosslinking points in the ionomer. In that case, instead of the phase angle δ of the ionomer, the phase angle of the copolymer of the raw materials of the ionomer may be used as an indicator of the linearity of the ionomer's main chain. The phase angle of the raw material copolymer may be 50 to 75 degrees, 50 to 70 degrees, 50 to 65 degrees, or 50 to 60 degrees.

[0090] 2. Method for producing ionomers The ionomers preferably have a linear molecular structure, and also, １３The number of methyl branches calculated by C-NMR is 50 or less per 1,000 carbon atoms, or the sum of the number of ethyl branches and butyl branches is less than 4.2 per 1,000 carbon atoms. From this viewpoint, it is preferable that the ionomer is produced in the presence of a transition metal catalyst.

[0091] (1) Polymerization catalyst The type of polymerization catalyst used in the production of copolymers of raw materials for ionomers is not particularly limited as long as it is capable of copolymerizing each monomer from which structural unit (A), structural unit (B), and structural unit (C) originate. For example, transition metal compounds of groups 5 to 11 having a chelating ligand are used. Specific examples of preferred transition metals include vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, iron, platinum, ruthenium, cobalt, rhodium, nickel, palladium, and copper atoms. Among these, transition metals of groups 8 to 11 are preferred, transition metals of group 10 are preferred, and nickel or palladium atoms are particularly preferred. These transition metals may be used individually or in combination.

[0092] Chelating ligands contain ligands that have at least two atoms selected from the group consisting of phosphorus (P), nitrogen (N), oxygen (O), and sulfur (S), and are bidentate or multidentate coordinates, and are electronically neutral or anionic. Examples of chelating ligand structures are provided in a review by Brookhart et al. (Chem. Rev., 2000, 100, 1169).

[0093] Preferably, bidentate anionic P,O ligands are used as chelating ligands. Examples of bidentate anionic P,O ligands include phosphosulfonic acid, phosphocarboxylic acid, phosphorus phenol, and phosphorus enolate. Other chelating ligands include bidentate anionic N,O ligands. Examples of bidentate anionic N,O ligands include salicylaldehyde and pyridinecarboxylic acid. Other chelating ligands include diimine ligands, diphenoxide ligands, and diamide ligands.

[0094] The structure of the metal complex obtained from the chelating ligand is represented by the following general formula (5) or (6), to which an arylphosphine compound, arylarsine compound, or arylantimony compound, which may have substituents, is coordinated. [In equations (5) and (6), M represents a transition metal atom belonging to any of groups 5 to 11 of the periodic table of elements, i.e., various transition metal atoms as described above. X １ It is oxygen, sulfur, -SO ３ -, or -CO ２ Represents -. Y １ represents carbon or silicon. n represents an integer of 0 or 1, and when n is 0, -Y １ (R ５５ ) ２ - does not exist, Y １ C and E are joined together １ They bond directly. E １ R represents phosphorus, arsenic, or antimony. ５３ and multiple R ５４ Each of these independently represents a hydrocarbon group which may contain hydrogen or a heteroatom having 1 to 30 carbon atoms. ５５ Each of these independently represents a hydrocarbon group which may contain hydrogen, a halogen, or a heteroatom having 1 to 30 carbon atoms. ５６ and R ５７ Each of these independently contains hydrogen, halogen, a hydrocarbon group which may contain a heteroatom having 1 to 30 carbon atoms, OR ５２ CO ２ R ５２ CO ２ M', C(O)N(R ５１ ) ２ , C(O)R ５２ , SR ５２ SO ２ R ５２ , SOR ５２ OSO ２ R ５２ , P(O)(OR ５２ ) ２－ｙ (R ５１ ) ｙ , CN, NHR ５２ , N(R ５２ )２ , Si(OR ５１ ) ３－ｘ (R ５１ ) ｘ , OSi(OR ５１ ) ３－ｘ (R ５１ ) ｘ NO ２ SO ３ M', PO ３ M' ２ , P(O)(OR ５２ ) ２ M' represents an epoxy-containing group. ５１ R represents hydrogen or a hydrocarbon group having 1 to 20 carbon atoms. ５２ represents a hydrocarbon group with 1 to 20 carbon atoms. M' represents an alkali metal, alkaline earth metal, ammonium, quaternary ammonium, or phosphonium, x is an integer from 0 to 3, and y is an integer from 0 to 2. Note that R ５６ and R ５７ These elements may be linked together to form an alicyclic ring, an aromatic ring, or a heterocycle containing a heteroatom selected from oxygen, nitrogen, or sulfur. In this case, the number of ring members is 5 to 8, and the ring may or may not have substituents. １ This represents the ligand coordinated to M. Also, R ５３ and L １ They may join together to form a ring.

[0095] More preferably, it is a transition metal complex represented by the following general formula (7). [In equation (7), M represents a transition metal belonging to any of groups 5 to 11 of the periodic table of elements, i.e., various transition metal atoms as described above. X １ It is oxygen, sulfur, -SO ３ -, or -CO ２ Represents -. Y １ represents carbon or silicon. n represents an integer of 0 or 1, and when n is 0, -Y １ (R ５５ ) ２ - does not exist, Y １ The carbon atoms of the benzene ring that bond with E １ They bond directly. E １R represents phosphorus, arsenic, or antimony. ５３ and multiple R ５４ Each of these independently represents a hydrocarbon group which may contain hydrogen or a heteroatom having 1 to 30 carbon atoms. ５５ Each of these independently represents a hydrocarbon group which may contain hydrogen, a halogen, or a heteroatom having 1 to 30 carbon atoms. ５８ , R ５９ , R ６０ and R ６１ Each of these independently contains hydrogen, halogen, a hydrocarbon group which may contain a heteroatom having 1 to 30 carbon atoms, OR ５２ CO ２ R ５２ CO ２ M', C(O)N(R ５１ ) ２ , C(O)R ５２ , SR ５２ SO ２ R ５２ , SOR ５２ OSO ２ R ５２ , P(O)(OR ５２ ) ２－ｙ (R ５１ ) ｙ , CN, NHR ５２ , N(R ５２ ) ２ , Si(OR ５１ ) ３－ｘ (R ５１ ) ｘ , OSi(OR ５１ ) ３－ｘ (R ５１ ) ｘ NO ２ SO ３ M', PO ３ M' ２ , P(O)(OR ５２ ) ２ M' represents an epoxy-containing group. ５１ R represents hydrogen or a hydrocarbon group having 1 to 20 carbon atoms. ５２ represents a hydrocarbon group with 1 to 20 carbon atoms. M' represents an alkali metal, alkaline earth metal, ammonium, quaternary ammonium, or phosphonium, x is an integer from 0 to 3, and y is an integer from 0 to 2. Note that R５８ ~R ６１ Multiple groups appropriately selected from may be linked together to form an alicyclic ring, an aromatic ring, or a heterocycle containing a heteroatom selected from oxygen, nitrogen, or sulfur. In this case, the number of ring members is 5 to 8, and the ring may or may not have substituents. １ This represents the ligand coordinated to M. Also, R ５３ and L １ They may join together to form a ring.

[0096] Here, typical catalysts for transition metal compounds of groups 5 to 11 having chelating ligands include so-called SHOP catalysts and Drent catalysts. SHOP catalysts are catalysts in which a phosphorus ligand having an optionally substituted aryl group is coordinated to nickel metal (see, for example, WO2010 / 050256). Drent catalysts are catalysts in which a phosphorus ligand having an optionally substituted aryl group is coordinated to palladium metal (see, for example, Japanese Patent Application Publication No. 2010-202647).

[0097] (2) Polymerization method for copolymers The polymerization method for producing copolymers of ionomer raw materials is not limited. Examples of polymerization methods include slurry polymerization in which at least a portion of the resulting polymer becomes a slurry in the medium, bulk polymerization using the liquefied monomer itself as the medium, gas-phase polymerization carried out in vaporized monomer, or high-pressure ionic polymerization in which at least a portion of the resulting polymer dissolves in monomer liquefied at high temperature and pressure. The polymerization form may be batch polymerization, semi-batch polymerization, or continuous polymerization.

[0098] Furthermore, living polymerization may be carried out, or polymerization may be carried out while chain transfer occurs concurrently. In addition, a so-called chain shuttling agent (CSA) may be used in combination during polymerization to carry out a chain shuttling reaction or coordinated chain transfer polymerization (CCTP). Specific manufacturing processes and conditions are disclosed, for example, in Japanese Patent Publication No. 2010-260913 and Japanese Patent Publication No. 2010-202647.

[0099] (3) Method for introducing a carboxyl group or a dicarboxylic acid anhydride group The structural unit (B) in the ionomer may be obtained directly by copolymerizing a monomer having at least one selected from the group consisting of a carboxyl group and a dicarboxylic acid anhydride group, as described above, or at least one selected from the group consisting of a carboxyl group and a dicarboxylic acid anhydride group may be introduced into the structure by modification after copolymerizing another monomer. The method of introduction can be selected from a variety of methods without departing from the spirit of the present invention and is not particularly limited.

[0100] Methods for introducing at least one selected from the group consisting of carboxyl groups and dicarboxylic acid anhydride groups by modification include, for example, when introducing a carboxyl group, a method of copolymerizing an acrylic acid ester and then hydrolyzing it to change it into a carboxyl group, or a method of copolymerizing an acrylic acid ester and then changing it into a carboxyl group by thermal decomposition.

[0101] When hydrolyzing or thermally decomposing as described above, conventionally known acid or base catalysts may be used as additives to promote the reaction. There are no particular limitations on the acid or base catalyst, but examples of suitable catalysts include alkali metal or alkaline earth metal hydroxides such as sodium hydroxide, potassium hydroxide, and lithium hydroxide; alkali metal or alkaline earth metal carbonates such as sodium bicarbonate and sodium carbonate; solid acids such as montmorillonite; inorganic acids such as hydrochloric acid, nitric acid, and sulfuric acid; and organic acids such as formic acid, acetic acid, benzoic acid, citric acid, p-toluenesulfonic acid, trifluoroacetic acid, and trifluoromethanesulfonic acid. From the viewpoint of reaction promoting effect, cost, and equipment corrosion, sodium hydroxide, potassium hydroxide, sodium carbonate, p-toluenesulfonic acid, or trifluoroacetic acid are preferred, and p-toluenesulfonic acid or trifluoroacetic acid are more preferred.

[0102] (4) The ionomer with a carboxylic acid metal base is a copolymer containing structural unit (A) and structural unit (B) obtained by the method described above, M １ and M ２ Compounds containing or M ３The ionomer may also be obtained by treating it with a compound containing and converting the carboxyl group or dicarboxylic anhydride group into a carboxylate metal base. Alternatively, the ionomer may be obtained by heating a copolymer having structural unit (A) and structural units derived from an unsaturated carboxylic acid ester, and converting at least some of the ester groups in the copolymer into carboxyl groups, or by directly converting the ester groups into M １ and M ２ or M ３ It may also be obtained by a heating conversion step that converts it to a carboxylic acid metal base containing M. １ and M ２ The compound containing M may be a single compound. １ and M ２ Each compound containing separately may be used in combination. Also, the above M ３ The compound containing M may be a single compound. ３ Compounds containing separately may be used in combination. Also, in the first embodiment, M is produced by the method described above. １ Ionomer (1) and M ２ An ionomer (2) having the above properties may be manufactured separately, and then the two may be melt-mixed or otherwise combined to obtain the ionomer. The apparatus and conditions for melt-mixing or other methods are the same as those described later with respect to the ionomer.

[0103] When an ionomer is produced by introducing a carboxyl group and / or a dicarboxylic acid anhydride group into a polymer, the production method is as follows, for example: A metal atom source is prepared by heating and kneading a metal salt with a substance that captures metal atoms (ions), such as ethylene / (meth)acrylic acid ((M)AA) copolymer, and then the metal atom source is added to the copolymer raw material of the ionomer in an amount that results in a desired degree of neutralization, and kneaded to obtain the ionomer.

[0104] Furthermore, in the heating conversion step, (i) a copolymer of ethylene and at least one selected from the group consisting of α-olefins having 3 to 20 carbon atoms and an unsaturated carboxylic acid ester is heated, and hydrolysis or thermal decomposition is performed to obtain a copolymer of ethylene and at least one selected from the group consisting of α-olefins having 3 to 20 carbon atoms and an unsaturated carboxylic acid, and then M１ and M ２ Compounds containing or M ３ The carboxyl groups in the copolymer may be converted to metal carboxylic acid bases by reacting with a compound containing (ii) ethylene and at least one selected from the group consisting of α-olefins having 3 to 20 carbon atoms and an unsaturated carboxylic acid ester, and while hydrolyzing or thermally decomposing the ester groups of the copolymer, M １ and M ２ Compounds containing or M ３ The ester group portion of the copolymer may be converted to a carboxylic acid metal base by reacting it with a compound containing the same compound.

[0105] M １ and M ２ Compounds containing M ３ The compounds containing the metal may be oxides, hydroxides, carbonates, bicarbonates, acetates, formates, etc. １ and M ２ Compounds containing M ３ The compound containing the compound may be supplied to the reaction system in granular or fine powder form. Alternatively, the compound may be dissolved or dispersed in water or an organic solvent before being supplied to the reaction system. Furthermore, a masterbatch may be prepared using, for example, a copolymer of ethylene and an unsaturated carboxylic acid or an olefin copolymer as the base polymer, and the compound may be supplied to the reaction system from this masterbatch. To ensure the reaction proceeds smoothly, it may be preferable to prepare a masterbatch and supply the compound to the reaction system from this masterbatch.

[0106] Furthermore, M １ and M ２ Compounds containing or M ３ The reaction with compounds containing may be carried out by melt-kneading using various types of equipment such as vent extruders, Banbury mixers, and roll mills. The reaction may be carried out in batch or continuous order. Since the reaction can be carried out smoothly by removing the by-products of water and carbon dioxide using a degasser, the reaction may be carried out continuously using an extruder equipped with a degasser, such as a vent extruder. １ and M ２ Compounds containing or M３ When reacting with compounds containing [the substance], a small amount of water may be added to accelerate the reaction.

[0107] The heating temperature for a copolymer of ethylene and at least one selected from the group consisting of α-olefins having 3 to 20 carbon atoms, and an unsaturated carboxylic acid ester, should be such that the ester groups are converted to carboxyl groups. If the heating temperature is too low, the ester groups will not be converted to carboxyl groups, and if it is too high, decarbonylation and decomposition of the copolymer will proceed. Therefore, the heating temperature may be in the range of 80°C to 350°C, 100°C to 340°C, 150°C to 330°C, or 200°C to 320°C. Within this range, it is thought that the conversion from ester groups to carboxyl groups will proceed, and decarbonylation and decomposition of the copolymer will be suppressed.

[0108] The reaction time varies depending on the heating temperature and the reactivity of the ester group. The reaction time is usually between 1 minute and 50 hours, but may be between 2 minutes and 30 hours, between 2 minutes and 10 hours, between 2 minutes and 3 hours, or between 3 minutes and 2 hours.

[0109] There are no particular restrictions on the reaction atmosphere in the above process. The above process may be carried out under an inert gas stream. Examples of inert gases that can be used include nitrogen, argon, and carbon dioxide. Small amounts of oxygen or air may be present.

[0110] There are no particular restrictions on the reactor used in the above process. The reactor is not limited in any way as long as it can stir the copolymer substantially uniformly. A glass vessel equipped with a stirrer or an autoclave (AC) may be used. Any conventionally known kneader, such as a Brabender plastograph, a single-screw or twin-screw extruder, a heavy-duty screw kneader, a Banbury mixer, a kneader, or a roll, can be used.

[0111] M １ and M ２ or M ３Whether the ionomer has been introduced and obtained can be confirmed by measuring the IR spectra of the copolymer before and after the reaction and examining the decrease in the peak originating from the carbonyl group of the carboxylic acid (dimer). Similarly, the degree of neutralization can be confirmed by examining the decrease in the peak originating from the carbonyl group of the carboxylic acid (dimer) and the increase in the peak originating from the carbonyl group of the carboxylic acid metal base, in addition to the calculation from the molar ratio mentioned above. Furthermore, the degree of neutralization of the ionomer may be determined from the amount of metal atoms supplied (material balance) when producing the ionomer from the raw material copolymer, which is an unsaturated carboxylic acid ester copolymer or an unsaturated carboxylic acid copolymer. Specifically, the degree of neutralization may be calculated by supplying a predetermined amount of metal atoms relative to the amount of ester in the unsaturated carboxylic acid ester copolymer or the amount of acid in the unsaturated carboxylic acid copolymer (e.g., mol% of carboxyl groups), and assuming that the entire amount of metal atoms has been converted to a carboxylic acid metal salt. In this case, the degree of neutralization of an ionomer obtained by mixing multiple types of ionomers may be calculated by multiplying the degree of neutralization of each ionomer by its blending ratio (weight ratio) and summing them up, provided that the raw material copolymers are the same.

[0112] If the copolymers of the raw materials are not the same, the degree of neutralization of the ionomer obtained by mixing multiple types of ionomers can also be determined as follows: (Copolymer) of each raw material corresponding to the multiple types of ionomers ｉ Let i represent the type of copolymer. (Copolymer) ｉ Regarding the average molecular weight of the monomer, m ｉ , acid amount AA ｉ (mol%, (copolymer) ｉ The amount of acidic functional groups such as carboxyl groups contained in the ionomer, for example, the amount of structural units of structural unit (B) or the amount of structural units of structural unit (B) multiplied by the number of acidic functional groups such as carboxyl groups contained in structural unit (B)), and the degree of neutralization of the ionomer n ｉ (mol%), the weight-to-weight ratio of the ionomer ｉ(Assuming weight %). Below, we will explain using specific examples for two types, i = 1 and i = 2, in which the raw material copolymer has one carboxyl group (for example, acrylic acid). If the amount of carboxyl groups in the raw material copolymer is (mol%), total COOH, and the amount of COO groups in the ionomer is (mol%), then the degree of neutralization of the ionomer, total COOH, and total COO can be expressed by the following relationships (W) to (Z). Degree of neutralization = total COO / total COOH: Equation (W) Total COOH = w １ / m １ ×AA １ +w ２ / m ２ ×AA ２ :Formula (X) Total COO=n １ × (w １ / m １ ×AA １ ) + n ２ × (w ２ / m ２ ×AA ２ ): Equation (Y) From the above equations (W) to (Y), the degree of neutralization of the entire ionomer is: Degree of neutralization of the entire ionomer = n １ × (w １ / m １ ×AA １ ) / (w １ / m １ ×AA １ +w ２ / m ２ ×AA ２ ) + n ２ × (w ２ / m ２ ×AA ２ ) / (w １ / m １ ×AA １ +w ２ / m ２ ×AA ２ ): Equation (Z) Note that m ｉ When structural unit (A) is ethylene and structural unit (B) is acrylic acid, the molecular weight of ethylene (ma, 28) and the molecular weight of acrylic acid (mb, 72) are given by AA. ｉ It can be defined in the following form: m ｉ = ma × (1 - AA ｉ ) + mb × AA ｉ :Formula (V)

[0113] (5) Strain hardening Strain hardening is a characteristic in which the viscosity of a material increases rapidly when it is stretched. This characteristic prevents localized thinning of the wall when a free surface exists during molding processes such as blow molding and film molding, resulting in effects such as uniform wall thickness of the molded product. Materials with strong strain hardening properties have superior moldability. Regarding the measurement method for strain hardening, any method that can measure uniaxial extensional viscosity will, in principle, yield the same value. Details of the measurement method and measuring equipment are described, for example, in Non-Patent Documents 4 and 5. The evaluation method for strain hardening can be evaluated by the degree of strain hardening (λmax) described in the examples. λmax is a value that indicates the degree of formation of pseudo-crosslinking points that the ionomer has. The higher this value, the better the moldability. Conversely, a low value of λmax indicates a low degree of formation of pseudo-crosslinking points. λmax is preferably 2.4 or higher, and if it is above this value, the balance between the fluidity and melt tension of the ionomer or resin composition containing the ionomer is good, and the moldability is easily improved. λmax may be 2.5 or higher, and may be 3.0 or higher. There is no particular upper limit to λmax; the higher the better. On the other hand, from the perspective of the limit value due to molecular slicing, the upper limit of λmax is considered to be 30.0. Furthermore, if λmax is 30.0 or less, the fluidity and melt tension of the ionomer and the resin composition containing the ionomer are excellent, and the impact strength and transparency of the molded articles obtained therefrom are also easily maintained. λmax may be 2.4 to 30.0, 2.5 to 25.0, 2.6 to 20.0, 2.7 to 15.0, 2.8 to 10.0, 3.2 to 15.0, and 2.4 to 9.4.

[0114] 3. The resin composition and molded articles containing the ionomer exhibit high strain-curability and excellent moldability, and the resulting molded articles have good properties such as mechanical strength and transparency. The ionomer can be suitably used as a raw material for various molded articles. One aspect of the present invention is a resin composition containing an ionomer. The resin composition is not particularly limited in terms of other components as long as it contains an ionomer. Within the scope of the present invention, the resin composition may contain resins other than the ionomer; and conventionally known additives such as antioxidants, ultraviolet absorbers, lubricants, antistatic agents, colorants, pigments, crosslinking agents, foaming agents, nucleating agents, flame retardants, conductive materials, and fillers.

[0115] Other olefin polymers are suitably used as resins other than ionomers. Examples of other olefin polymers include low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, ethylene propylene rubber, ethylene propylene diene rubber, and polybutene. Furthermore, the resin composition of this disclosure can use various resins other than the above-mentioned olefin polymers. Specifically, examples include various polyamides, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), various polyesters, polycarbonate resins, EVOH, EVA, PMMA, PMA, various engineering plastics, biodegradable resins such as polylactic acid, celluloses, natural rubbers, polyurethanes, polystyrene, polyvinyl chloride, fluoropolymers such as Teflon (registered trademark), and inorganic polymers such as silicone resins.

[0116] Another aspect of the present invention is a molded article comprising a resin composition. Examples of molding methods include blow molding, injection molding, extrusion molding, film molding, and foam molding. Because ionomers and resin compositions containing them have high strain-curing properties, they can be suitably used in molding processes where a free surface exists, such as blow molding and film molding. In film molding, even if thickness variations occur during the molding process, ionomers and compositions containing them increase viscosity in the thinner areas, preventing film breakage and stabilizing the process. Furthermore, because ionomers and compositions containing them prevent localized thinning during molding and ensure uniform wall thickness of the molded article, they can stabilize the process in blow molding and foam molding as well, similar to film molding. In addition, ionomers and compositions containing them can suppress the generation of burrs during injection molding. In injection molding, when resin enters the gap between the molds from a wide cavity, the resin undergoes tensile flow. Because ionomers and compositions containing them increase viscosity when stretched, they become difficult to stretch, thus suppressing the generation of burrs.

[0117] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. The physical properties in the examples and comparative examples were measured and evaluated by the methods shown below.

[0118] <Measurement and Evaluation of Physical Properties> (1) Absolute value G of the complex modulus ＊ = Phase angle δ(G) at 0.1 MPa ＊Measurement of 0.1 MPa 1) Preparation of the sample: 1 g of each of the copolymer raw materials (P2-1) and (P2-2), as well as the ionomers of the examples and comparative examples, was placed in a 1.0 mm thick heat press mold and preheated in a hot press machine at a surface temperature of 180°C for 5 minutes. Then, residual gas in the molten resin was removed by repeatedly applying and releasing pressure (less than 1.0 MPa) for 30 seconds. Next, the pressure was increased to 4.9 MPa and held for 5 minutes. After depressurization, the sample was transferred to a press machine at a surface temperature of 25°C, pressurized to 4.9 MPa and held for 3 minutes, and then cooled. In this way, a sample press plate with a thickness of approximately 1.0 mm was prepared. This sample press plate was processed into a 25 mm diameter circle and used as the measurement sample. Dynamic viscoelasticity was measured using the following apparatus and conditions. • Under a nitrogen atmosphere • Equipment: Rheometers ARES type rotary rheometer • Plate: φ25 mm (diameter) parallel plate • Temperature: 160°C • Strain: 10% • Measurement angular frequency range: 1.0 × 10⁻⁶ －２ ~1.0 x 10 ２ rad / s Measurement interval: 5 points / decade 2) How to determine the phase angle δ: Absolute value G of the complex modulus of elasticity ＊ The common logarithm of (Pa) logG ＊ We plot the phase angle δ against logG. ＊ = The value of δ (degrees) at the point corresponding to 5.0 is the phase angle δ (G ＊ (= 0.1 MPa) was used. logG was placed inside the measurement point. ＊ = If there is no point corresponding to 5.0, logG ＊ = Using two points around 5.0, logG ＊ The δ value at =5.0 was determined by linear interpolation. Also, all measurement points were log G. ＊ <When it is 5, logG ＊ Using the three largest values, plot log G using a quadratic curve. ＊ The δ value at =5.0 was obtained by extrapolation.

[0119] (2) Mw and Mw / Mn were measured for the copolymers (P1-1) and (P1-2) of the raw materials. Mw was determined by gel permeation chromatography (GPC). Mw / Mn was calculated by determining Mn using GPC, and then calculating the ratio of Mw to Mn, Mw / Mn. The measurements were carried out according to the following procedure and conditions.

[0120] 1) Preparation of sample solution: 3 mg of the sample and 3 mL of o-dichlorobenzene (ODCB) were weighed into a 4 mL vial, sealed with a screw cap and a Teflon® septum, and shaken at 150°C for 2 hours using a Senshu Kagaku Co., Ltd. SSC-7300 high-temperature shaker. After shaking, it was visually confirmed that there were no insoluble components.

[0121] 2) Apparatus and Measurement Conditions Apparatus: Waters Alliance GPCV2000 Column: Showa Denko Corporation Showdex HT-G x 1 and HT-806M x 2 Eluent: ODCB Flow rate: 1.0 mL / min Temperature: 145°C

[0122] 3) Calibration curve: The column was calibrated by measuring monodisperse polystyrene (S-7300, S-3900, S-1950, S-1460, S-1010, S-565, S-152, S-66.0, S-28.5, S-5.05, each at 0.07 mg / mL solution, solvent: ODCB), n-eicosane, and n-tetracontane (each at 0.07 mg / mL solution, solvent: ODCB) manufactured by Showa Denko K.K. under the same conditions as above, and elution time and the logarithm of molecular weight were approximated by a quartic equation. Note that the molecular weight of polystyrene (M ＰＳ ) and polyethylene molecular weight (M ＰＥ The following formula was used for the conversion of M. ＰＥ = 0.468 × M ＰＳ

[0123] (3) Melt Flow Rate (MFR) The MFR was measured for the raw material copolymers (P2-1) and (P2-2). The MFR was measured according to Table 1 - Condition 7 of JIS K-7210 (1999) at a temperature of 190°C and a load of 21.18 N (= 2.16 kg).

[0124] (4) Method for measuring the amount of structural units of structural unit (B) and the number of branches per 1,000 carbon atoms The amount of structural units of structural unit (B) and the number of branches per 1,000 carbon atoms １３ This was determined using C-NMR spectroscopy. １３ ¹³C-NMR was measured by the following method: 1) Sample preparation: 200-300 mg of the copolymers (P1-1) and (P1-2) of the raw materials were mixed with ODCB and deuterated bromide (¹³C). ６ D ５ Mixed solvent of Br (ODCB / C ６ D ５ 2.4 mL of Br (3 / 1 by volume) and hexamethyldisiloxane as a reference substance for chemical shift were placed in a 10 mmφ NMR tube, purged with nitrogen, and then sealed. Next, it was heated and dissolved at 150°C to obtain a homogeneous solution which was used as the NMR measurement sample. 2) Apparatus and measurement conditions Apparatus: Bruker Japan Co., Ltd. AV400M NMR probe: 10 mmφ cryoprebe Temperature: 120°C Pulse angle: 90° Pulse interval: 51.5 seconds Number of integrations: 512 or more Reverse gate decoupling method Chemical shift was measured using hexamethyldisiloxane. １３ Set the C signal to 1.98 ppm, and the other １３ The chemical shift of the signal due to C was based on this.

[0125] 3) Calculation of comonomer content <Ethylene (E) / t-butyl acrylate (tBA)> The quaternary carbon signal of the t-butyl group in tBA is １３ Chemical shifts in the 13C-NMR spectrum are detected in the range of 79.6–78.8. Using these signal intensities, the tBA content was calculated from the following formula: Total tBA (mol%) = I(tBA) × 100 / [I(tBA) + I(E)] where I(tBA) and I(E) are the quantities shown in the following formulas: I(tBA) = I ７９．６～７８．８ I(E) = (I １８０．０～１３５．０ +I １２０．０～５．０ -I(tBA)×7) / 2

[0126] 4) Calculation of the number of branches per 1,000 carbon atoms The number of branches per 1,000 carbon atoms was calculated by substituting one of the following I(B1), I(B2), and I(B4) into I(branching) in the following equation (8). B1 represents methyl branching, B2 represents ethyl branching, and B4 represents butyl branching. The number of methyl branchings was calculated using I(B1), the number of ethyl branchings was calculated using I(B2), and the number of butyl branchings was calculated using I(B4). Number of branches (number of branches / per 1,000 carbon atoms) = I(branching) × 1000 / I(total) ... (8) Here, I(total), I(B1), I(B2), and I(B4) are quantities shown in the following equation. I(total) = I １８０．０～１３５．０ +I １２０．０～５．０ I(B1) = (I ２０．０～１９．８ +I ３３．２～３３．１ +I ３７．５～３７．３ ) / 4 I(B2)=I ８．６～７．６ +I １１．８～１０．５ I(B4) = I １４．３～１３．７ -I ３２．２～３２．０ Here, I is the integral intensity, and the numerical subscript to I indicates the range of the chemical shift. For example, I １８０．０～１３５．０ It was detected between 180.0 ppm and 135.0 ppm. １３ The integrated intensity of the C signal is shown. Attributions are based on non-patent literature Macromolecules 1984, 17, 1756-1761 and Macromolecules 1979, 12, 41. Note that when each branching number is indicated with an inequality sign "<0.1", it means that it exists as a constituent unit in the copolymer, but considering significant figures, the amount is less than 0.1 per 1000 carbon atoms. Also, n.d. means below the detection limit.

[0127] (5) Infrared Absorption Spectrum (IR Spectrum) 0.1 g of each of the raw material copolymers (P2-1) and (P2-2), as well as the ionomers of the Examples and Comparative Examples, was melted in a hot press at a surface temperature of 180°C for 3 minutes. Then, it was compressed to produce a film with a thickness of approximately 50 μm. This film was analyzed by Fourier transform infrared spectroscopy to obtain the infrared absorption spectrum. Using this procedure, the structural unit amounts of structural unit (B) and structural unit (C) were determined by the calculation method described in Example 1 below. Apparatus: FT / IR-6100, manufactured by JASCO Corporation. Measurement method: Transmission method. Detector: TGS (Triglycine sulfate). Number of integrations: 16 to 512. Resolution: 4.0 cm. －１ Measurement wavelength: 5000-500cm －１

[0128] (6) Evaluation Method for Strain Hardening The strain hardening property was evaluated by the degree of strain hardening (λmax). Regarding the method for measuring the degree of strain hardening, any method that can measure uniaxial extensional viscosity will, in principle, yield the same value, and details of the measurement method and measuring equipment are described, for example, in Non-Patent Documents 4 and 5. In the present invention, the following measurement method and measuring equipment were used to measure test specimens prepared by the following method. (Preparation of Test Specimens) 0.2 g of the sample was placed in an 18 mm × 10 mm × 0.7 mm heating press mold and preheated in a hot press machine at a surface temperature of 140 °C for 15 seconds. Then, residual gas in the molten resin was removed by repeatedly applying pressure (less than 1.0 MPa) and depressurizing for 15 seconds. Next, the pressure was increased to 10 MPa and held for 270 seconds. After depressurization, the sample was transferred to a press machine at a surface temperature of 25 °C, pressurized to 10 MPa and held for 3 minutes, and then cooled. In this way, a strip-shaped sheet measuring 18 mm × 10 mm × 0.7 mm was obtained. (Measurement method) Apparatus: ARES G2 manufactured by T.A. Instruments Co., Ltd. Fixture: Extensional viscosity measurement fixture manufactured by T.A. Instruments Co., Ltd. Measurement temperature: 140°C Strain rate: 0.2 [unit: 1 / sec] (Method for calculating λmax) For the extensional viscosity measured under the above conditions, time t (seconds) was plotted on the horizontal axis and extensional viscosity η(t) (Pa·seconds) on the vertical axis on a log-log scale. Figure 3 shows the log-log plot of the ionomer of Example 4. First, the relationship between η(t) and time t just before the extensional viscosity rapidly increases (strain hardening) on ​​the log-log plot was approximated by a straight line, and η ｌｉｎ (t) was obtained. η ｌｉｎ (t) is the tangent line with the smallest slope among the tangent lines to the curve on a log-log graph within the range of t corresponding to strain amounts from 0.2 to 1.0. Next, the maximum value of η(t) after strain hardening occurs (η ｍａｘ (t １ ), hereafter η ｍａｘ It is also said that the time at that moment １ We determined the following. In the ionomer of Example 4, t = t １ The test specimen fractured, therefore the extensional viscosity η(t) is given by t = t １ It is maximized at (η) ｍａｘ (t １ )). Also, the time t when η(t) is maximum. １ In the above approximate linear relationship, the extensional viscosity is ηｌｉｎ (t １ ) (hereinafter η ｌｉｎ It is also called ). λmax is η ｍａｘ (t １ ) and η ｌｉｎ (t １ ) ratio (η ｍａｘ (t １ ) / η ｌｉｎ (t １ Defined as follows:

[0129] (7) Using the copolymers (P2-1) and (P2-2) of the tensile test raw materials, sheets with a thickness of 1 mm were prepared by the method (cooling method A) described in JIS K7151 (1995). The obtained sheets were punched out to prepare small 5B type test specimens as described in JIS K7162 (1994). The tensile modulus, tensile breaking stress, and tensile breaking elongation of these test specimens were measured according to JIS K7161 (2014) at a temperature of 23 ± 2 °C and a test speed of 10 mm / min.

[0130] (8) Tensile Impact Strength Test 1) Method for Preparing Tensile Impact Strength Test Samples The copolymer raw materials (P2-1) and (P2-2) were placed in a 1 mm thick heat press mold and preheated in a hot press machine at a surface temperature of 180°C for 5 minutes. After 5 minutes, pressurization (1.0 MPa or less) and depressurization were repeated for 30 seconds to melt the resin and degas any residual gas from the molten resin. Then, the pressure was increased to 4.9 MPa and held for 5 minutes. Next, the pressure was maintained at 4.9 MPa and cooled at a rate of 10°C / min. When the surface temperature had decreased to near room temperature, the pressure was released and the molded plate was removed from the mold. The obtained molded plate was conditioned by placing it in an environment of 23±2°C and 50±5% humidity for 48 hours or more. Then, the molded plate was punched out into test pieces in the shape of ASTM D1822 Type-S. 2) Tensile Impact Strength Test Conditions Using the above test specimens, the tensile impact strength was measured in accordance with the method described in JIS K 7160-1996, except that the shape of the test specimens differed.

[0131] <Synthesis of Metal Complexes> (Synthesis Example 1) Synthesis of B-423 / Ni Complex According to Synthesis Example 1 described in Japanese Patent Publication No. 2019-156764, the following 2-bis(2,6-dimethoxyphenyl)phosphano-6-(2,6-diisopropylphenyl)phenol ligand (B-423) was synthesized. In accordance with Example 1 of Japanese Patent Publication No. 2019-156764, Ni(cod) ２ Using B-423 and Ni(code) ２ A nickel complex (B-423 / Ni complex) was synthesized by the reaction of two components in a 1:1 ratio.

[0132] <Production Example 1-1: Production of Copolymer (P1-1) of Ionomer Raw Materials> An ethylene / t-butyl acrylate copolymer was produced using the B-423 / Ni complex prepared by Synthesis Example 1 above as a metal catalyst component. Copolymer (P1-1) was produced with reference to Production Example 1 described in Japanese Patent Publication No. 2016-79408. The obtained copolymer (P1-1) had a Mw of 27,000 and an Mw / Mn of 2.2. Table 1 shows the production conditions, including the metal complex species and amount of metal complex used in polymerization, the amount of aluminum compound (trioctylaluminum (TnOA)), the amount of toluene, the comonomer species, the comonomer concentration, the ethylene partial pressure, the polymerization temperature, and the polymerization time.

[0133] <Production Example 1-2: Production of Copolymer (P1-2) of Ionomer Raw Materials> Copolymer (P1-2) was produced in the same manner as in Production Example 1-1, except that the production conditions such as the amount of metal complex, TnOA, toluene, comonomer species, comonomer concentration, ethylene partial pressure, polymerization temperature, and polymerization time were changed as shown in Table 1. The obtained copolymer (P1-2) had a Mw of 34,000 and an Mw / Mn of 2.3.

[0134]

[0135] <Production Example 2-1: Production of Copolymer (P2-1) of Ionomer Raw Materials> 40 g of P1-1, 0.8 g of p-toluenesulfonic acid monohydrate, and 185 mL of toluene were added to a 500 mL separable flask and stirred at 105°C for 4 hours. Then, 185 mL of deionized water was added to the resulting reaction mixture, stirred, and allowed to stand. Next, the organic layer and the aqueous layer were separated, and the aqueous layer was removed. The organic layer was washed by adding the above-mentioned deionized water to the obtained organic layer. The washing of the organic layer was repeated by adding deionized water and separating the aqueous layer until the pH of the removed aqueous layer was 5 or higher. After washing, the solvent was removed from the organic layer by vacuum distillation, and the mixture was dried until a constant weight was obtained to obtain copolymer (P2-1). The IR spectrum of P2-1 was measured. From the IR spectrum, the 850 cm⁻¹ component originated from the t-butyl group. －１ The nearby peak disappears, and the peak at 1730 cm originates from the carbonyl group of the ester. －１ A decrease in the nearby peak was observed. Additionally, the 1700 cm⁻¹ peak originating from the carbonyl group of the carboxylic acid (dimer) was also observed. －１ An increase in the surrounding peaks was observed. This confirmed the decomposition of t-butyl ester and the formation of carboxylic acid. In P2-1, the content of structural unit (A) was 96.9 mol%, the content of structural unit (B) was 3.1 mol%, and the phase angle δ was 62 degrees. The physical properties of P1-1 and P2-1 are shown in Tables 2 and 3, respectively.

[0136] <Production Example 2-2: Production of Copolymer (P2-2) of Ionomer Raw Materials> Copolymer (P2-2) was obtained by the same procedure as in Production Example 2-1, except that P1-1 used as the raw material copolymer was changed to P1-2. The IR spectrum of P2-2 was measured. From the IR spectrum, 850 cm⁻¹ was found to be derived from the t-butyl group. －１ The nearby peak disappears, and the peak at 1730 cm originates from the carbonyl group of the ester. －１ A decrease in the nearby peak was observed. Additionally, the 1700 cm⁻¹ peak originating from the carbonyl group of the carboxylic acid (dimer) was also observed. －１An increase in the surrounding peaks was observed. This confirmed the decomposition of t-butyl ester and the formation of carboxylic acid. In P2-2, the content of structural unit (A) was 96.3 mol%, the content of structural unit (B) was 3.7 mol%, and the phase angle δ was 59 degrees. The physical properties of P1-2 and P2-2 are shown in Tables 2 and 3, respectively.

[0137]

[0138]

[0139] <Preparation of Metal Atom Source> 1) Preparation of Li Source 30 ml of distilled water was mixed with lithium acetate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) in an amount required for the desired degree of neutralization (for a degree of neutralization of 10%, lithium acetate (0.011 mol × 0.1 = 0.0011 mol) corresponding to a degree of neutralization of 10% relative to the mol content of structural unit (B) in 10 g of copolymer (P2-1) (0.011 mol)) and dissolved to prepare an aqueous solution.

[0140] 2) Preparation of Zn source Similar to 1) above, zinc acetate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added to 30 ml of distilled water in an amount necessary for the desired degree of neutralization, and dissolved to prepare an aqueous solution.

[0141] 3) Preparation of Ag source In the same manner as in 1) above, silver acetate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added to 30 ml of distilled water in an amount necessary for the desired degree of neutralization, and dissolved to prepare an aqueous solution.

[0142] 4) Preparation of Na supply source Similar to 1) above, sodium acetate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added to 30 ml of distilled water in an amount necessary for the desired degree of neutralization, and dissolved to prepare an aqueous solution.

[0143] 5) Preparation of Fe supply source In the same manner as in 1) above, iron acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) was added to 30 ml of distilled water in an amount necessary for the desired degree of neutralization, and dissolved to prepare an aqueous solution.

[0144] 6) Preparation of Pb supply source In the same manner as in 1) above, lead acetate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added to 30 ml of distilled water in an amount necessary for the desired degree of neutralization, and dissolved to prepare an aqueous solution.

[0145] The following describes the ionomers of Examples 1 to 18, including the type of copolymer used as the raw material and the metal atom species M of ionomers (1) and (2). １ and M ２ The degree of neutralization and the amount added, as well as the degree of neutralization and phase angle of the entire ionomer, are summarized in Table 4. Furthermore, for the ionomers of Examples 19-22, the type of copolymer used as the raw material and the metal atom species M are also summarized. ３ The results of the degree of neutralization, blending amount, and phase angle are summarized in Table 5. Furthermore, for comparative example ionomer A, the type of copolymer of the raw materials and the metal atom species M of ionomers (1) and (2) were also analyzed. １ and M ２ The degree of neutralization, the amount added, and the degree of neutralization and phase angle of the entire ionomer A are summarized in Table 6. In Table 6, in Comparative Examples 4 to 12, the metal atom species of ionomer A was M １ The following information was recorded in the column, and the degree of neutralization and amount of ionomer A were recorded in the column for ionomer (1).

[0146] Example 1: 10 g of the copolymer (P2-1) was placed in an Xplore MC15 small kneader manufactured by Xplore Instruments, and kneaded at 160°C and 100 rpm for 3 minutes until it reached a molten state. Then, a Zn supply source was added to achieve a neutralization degree of 85%, and kneading was carried out at 200°C and 100 rpm for 15 minutes. After that, the temperature was increased to 250°C and 100 rpm for 5 minutes to obtain ionomer (1). Separately, 10 g of the copolymer (P2-1) was placed in an Xplore MC15 small kneader manufactured by Xplore Instruments, and kneaded at 160°C and 100 rpm for 3 minutes until it reached a molten state. Then, a Li supply source was added to achieve a neutralization degree of 45%, and kneading was carried out at 200°C and 100 rpm for 15 minutes. The temperature was then raised to 250°C and kneaded at 100 rpm for 5 minutes to obtain ionomer (2). Ionomers (1) and (2) obtained from the above were subjected to IR analysis. In the IR spectrum, the 1700 cm⁻¹ value originated from the carbonyl group of the carboxylic acid (dimer). －１ The peak in the vicinity decreases, and the 1560 cm⁻¹ peak originates from the carbonyl group of the carboxylic acid metal base. －１The peak in the vicinity was increasing. This confirmed the formation of structural units (C). The peak at 1700 cm² originated from the carbonyl group of the carboxylic acid (dimer). －１ The reduction in the surrounding peaks confirmed that the desired degree of neutralization of the ionomer had been produced. Ionomers (1) and (2) were added to an Xplore MC15 small kneader manufactured by Xplore Instruments at a concentration of 50% by weight each, and kneaded at 200°C and 100 rpm for 15 minutes. The temperature was then increased to 250°C and 100 rpm for 5 minutes to obtain the ionomer of Example 1. Table 4 summarizes the ionomer preparation conditions, the degree of neutralization of the ionomer (ratio of the mol content of structural unit (C) to the total mol content of structural unit (B) and structural unit (C)), and the phase angle.

[0147] Examples 2-18 and Comparative Examples 1-3: Ionomers of Examples 2-18 and Comparative Examples 1-3 were obtained in the same manner as in Example 1, except that the type of copolymer of the raw materials used to prepare ionomers (1) and (2), the type of metal atom source, the degree of neutralization, and the blending amounts of ionomers (1) and (2) were changed as shown in Tables 4 and 6. In the same manner as in Example 1, IR measurements were performed on ionomers (1) and (2), and it was confirmed that structural units (C) were formed.

[0148] Comparative Example 4: 10 g of the copolymer (P2-1) was placed in an Xplore MC15 small kneader manufactured by Xplore Instruments, and kneaded at 160°C and 100 rpm for 3 minutes until it reached a molten state. Then, a Li supply source was added to achieve a degree of neutralization of 25%, and kneading was carried out at 200°C and 100 rpm for 15 minutes. After that, the temperature was increased to 250°C and 100 rpm for 5 minutes to obtain the ionomer of Comparative Example 4. In the same manner as in Example 1, IR measurement of the ionomer was performed, and it was confirmed that structural units (C) had been formed.

[0149] Comparative Examples 5-10 Ionomers of Comparative Examples 5-10 were obtained in the same manner as in Comparative Example 4, except that the type of copolymer of the raw materials used to prepare the ionomers, the type of metal atom source, and the degree of neutralization were changed as shown in Table 6. In addition, as in Example 1, IR measurement was performed on the ionomers and it was confirmed that structural units (C) had been formed.

[0150] Comparative Example 11: Hymiran® ​​1650 (ethylene content 95.8 mol%) manufactured by Mitsui Dow Polychemical Co., Ltd. was used.

[0151] Comparative Example 12: Hymiran® ​​1605 (ethylene content 94.8 mol%) manufactured by Mitsui Dow Polychemical Co., Ltd. was used.

[0152] Examples 19-22: 10 g of P2-1 was added to an Xplore MC15 small kneader manufactured by Xplore Instruments, and kneaded at 160°C and 100 rpm for 3 minutes until molten. Subsequently, the ionomers of Examples 19-22 were obtained in the same manner as in Comparative Example 4, except that the type of metal atom source and degree of neutralization used for ionomer preparation were changed as shown in Table 5. In addition, as in Example 1, IR measurement of the ionomers was performed and it was confirmed that structural units (C) had been formed.

[0153]

[0154]

[0155]

[0156] For the ionomers of Examples 1 to 22 and Comparative Examples 1 to 10, the results of the evaluation of extensional viscosity, η ｍａｘ >η ｌｉｎ Table 7 shows whether the condition is satisfied and whether formulas (α) and (β) are satisfied (satisfied: ○, not satisfied: ×). Table 8 also shows the estimated values ​​of λmax (estimated from additivity) calculated from the blending amounts of ionomers (1) and (2) for Examples 3 to 5 and Comparative Examples 1 to 3, and the λmax of Comparative Examples 4 to 8 and 10.

[0157]

[0158]

[0159] <Discussion of the results of the examples and comparative examples> The ionomers of Examples 1 to 22 have structural unit (A), structural unit (B), and structural unit (C), and the number of branchings of the polymer chain is within a predetermined range, and all of them have η ｍａｘ (t １ )>η ｌｉｎ (t １ The ionomers satisfy the condition ( ) and at least one of formula (α) or (β). The ionomers of Examples 1 to 22 exhibit significantly higher strain hardening properties and superior moldability compared to the ionomers of Comparative Examples 1 to 10, which do not satisfy either formula (α) or (β). Furthermore, the ionomers of Examples 1 to 18 have a structural unit (C) in which the carboxylic acid metal base is composed of at least two metal atoms. １ and M ２ It contains M １ and M ２ The difference in electronegativity of the Pauling electronegativity χ Ｍ１ -χ Ｍ２ The value is 0.06 or higher. It can be seen that the λmax of Examples 1 to 18 is significantly higher than the λmax of the comparative example. Furthermore, in the ionomers of Examples 19 to 22, the carboxylic acid metal base in the structural unit (C) is a metal atom (M) with a Pauling electronegativity χ of 1.83 to 2.54. ３ It contains ). The λmax of Examples 19 to 22 is also significantly higher than that of the comparative examples. Furthermore, the strain hardening properties (λmax) of the ionomers of Examples 3 to 5 are significantly higher than the estimated values ​​(Table 8) calculated from the additivity based on the λmax of ionomers using one type of metal atom. That is, χ Ｍ１ -χ Ｍ２ It can be seen that the strain hardening properties of the resulting ionomer are synergistically improved by using two types of metal atoms with a ratio of 0.06 or higher. On the other hand, χ Ｍ１ -χ Ｍ２ In Comparative Examples 1 to 3, which used two types of metal atoms with a ratio of less than 0.06, no such synergistic effect was observed.

[0160] The ionomer of the present invention is useful because it has a superior balance of fluidity and strain-curing properties compared to conventional ionomers. Furthermore, the main chain of the ionomer has a very small number of short-chain branches and is substantially linear in structure, and it also possesses good impact resistance and adhesive properties, making it useful.

Claims

1. An ionomer comprising a structural unit (A) derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms; a structural unit (B) having at least one selected from the group consisting of a carboxy group and a dicarboxylic anhydride group; and a structural unit (C) having a metal carboxylate group. １ , ｌｉｎ , ｍａｘ , １ , ０．７ , １ , １ , ｌｉｎ , １ The number of methyl branches calculated by C-NMR is 50 or less per 1,000 carbon atoms, or the total number of ethyl branches and butyl branches is less than 4.2 per 1,000 carbon atoms. In a double logarithmic plot of the elongational viscosity η(t) (unit: Pa·s) obtained by uniaxial elongational viscosity measurement at 140°C and an elongation strain rate of 0.2 [1 / s] and the elongation time t (unit: s), the maximum elongational viscosity after strain hardening is η ｍａｘ (t １ ), the time t at that time is t １ , and when the approximate straight line of the elongational viscosity before strain hardening is η ｌｉｎ 0(t), η ｍａｘ (t １ ) and the elongational viscosity η １ on the approximate straight line at the time t ｌｉｎ (t １ ) satisfy η ｍａｘ (t １ ) > η ｌｉｎ (t １ ), and satisfy the following formula (α) or (β). η<000,00015>(t １ ) > 1.9η ｌｉｎ (t １ ) １．１ Formula (α) η ｍａｘ (t １ ) ≥ 1.9η ｌｉｎ (t １ ) ０．７ Formula (β) Here, the approximate straight line of the elongational viscosity before strain hardening: η ｌｉｎ (t) is the tangent line with the smallest slope among the tangent lines of the curve of the double logarithmic plot within the range of the elongation time t corresponding to a strain amount of 0.2 to 1.0, provided that the slope is zero or a positive value. Also, the units of η<000,00026>(t １ ) and η<00,00028>(t １ ) are MPa·s.

2. The above formula (α) is η ｍａｘ (t １ ) > 2.8η ｌｉｎ (t １ ) １．１ The ionomer according to claim 1.

3. The above formula (β) is η ｍａｘ (t １ ) ≥ 2.0η ｌｉｎ (t １ ) ０．７ The ionomer according to claim 1 or 2.

4. λmax = η ｍａｘ (t １ ) / η ｌｉｎ (t １ The ionomer according to any one of claims 1 to 3, wherein the degree of strain hardening λmax, as defined by ), is 2.4 or greater.

5. In the structural unit (C), the carboxylic acid metal base is a metal atom M with a Pauling electronegativity χ of 1.83 to 2.

54. ３ An ionomer according to any one of claims 1 to 4, comprising at least one of the above.

6. The ionomer according to any one of claims 1 to 5, wherein the ratio of the mol content of structural unit (C) to the sum of the mol content of structural unit (B) and structural unit (C) is 20 to 70 mol%.

7. The ionomer according to any one of claims 1 to 6, wherein the ratio of the sum of the mol content of structural unit (B) and structural unit (C) to the sum of the mol content of structural unit (A), structural unit (B), and structural unit (C) is 0.01 to 20.00 mol%.

8. The ionomer according to any one of claims 1 to 7, wherein the structural unit (A) is a structural unit derived from ethylene.

9. A structural unit (A) derived from at least one selected from the group consisting of ethylene and α-olefins having 3 to 20 carbon atoms; a structural unit (B) having at least one selected from the group consisting of a carboxyl group and a dicarboxylic acid anhydride group; and a structural unit (C) having a carboxylic acid metal base, wherein the carboxylic acid metal base is at least two metal atoms. １ and M ２ Contains the above M １ and the M ２ The electronegativity of Polling is χ, respectively. Ｍ１ and χ Ｍ２ When this is the case, χ Ｍ１ -χ Ｍ２ The structural unit (C) having a value of 0.06 or more includes, １３ An ionomer in which the number of methyl branches calculated by C-NMR is 50 or less per 1,000 carbon atoms, or the sum of the number of ethyl branches and butyl branches is less than 4.2 per 1,000 carbon atoms.

10. χ Ｍ１ -χ Ｍ２ The ionomer according to claim 9, wherein the ratio is 0.06 to 1.

84.

11. Said M １ is selected from the group consisting of iron, cobalt, nickel, copper, silver, and lead, and the M ２ is selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, and zinc, or the above M １ The M is selected from the group consisting of titanium, vanadium, chromium, manganese, and zinc. ２ The ionomer according to claim 9 or 10, wherein is selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, and barium.

12. The ionomer according to any one of claims 9 to 11, wherein the ratio of the mol content of structural unit (C) to the sum of the mol content of structural unit (B) and structural unit (C) is 20 to 70 mol%.

13. The ionomer according to any one of claims 9 to 12, wherein the ratio of the sum of the mol content of structural unit (B) and structural unit (C) to the sum of the mol content of structural unit (A), structural unit (B), and structural unit (C) is 0.01 to 20.00 mol%.

14. The ionomer according to any one of claims 9 to 13, wherein the structural unit (A) is a structural unit derived from ethylene.

15. A resin composition comprising the ionomer described in any one of claims 1 to 14.

16. A molded article comprising the resin composition described in claim 15.

Images