JP2022066784A - Polar group-containing 2-alkenyl monomer copolymer and method for producing the same, and oxygen barrier laminate - Google Patents

Abstract

To provide a polar group-containing 2-alkenyl monomer copolymer that has a high molecular weight and is soluble in a predetermined solvent, and to provide a method for producing the same.SOLUTION: Provided is a copolymer that has monomer structural units of the formulas (1), (2), and (3), and satisfies the following (A), (B), and (C). (A) a copolymer in which the molar ratios l, m, and n satisfy the following equation: 0.1≤[n/(l+m+n)]×100≤65. (B) the weight average molecular weight Mw is 10,000 to 1,000,000. (C) is not gelled and dissolves in a predetermined solvent.SELECTED DRAWING: None

Description

The present invention relates to a polar group-containing 2-alkenyl monomer copolymer, a method for producing the same, and an oxygen barrier laminate.

Polymers of vinyl monomers having a polar group such as acrylic acid ester, methacrylic acid ester, and vinyl acetate are widely known. For example, polyvinyl alcohol (hereinafter, may be abbreviated as PVOH) and ethylene-vinyl alcohol copolymer (hereinafter, may be abbreviated as EVOH) are radical polymerization of vinyl acetate or radical copolymerization of ethylene and vinyl acetate. It is produced by saponifying the polyvinyl acetate or ethylene-vinyl acetate copolymer obtained in the above. PVOH and EVOH are used in a wide range of fields such as food packaging applications by taking advantage of their excellent gas barrier properties.

On the other hand, the polymerization of a monomer having an allyl group is more difficult than that of a vinyl monomer such as vinyl acetate, and the polymer thereof is hardly known. The main reason is that when a monomer having an allyl group is radically polymerized, a degenerative chain transfer reaction to the monomer proceeds by extraction of a hydrogen atom existing on the allyl-position carbon atom, so that only an oligomer having a low degree of polymerization can be obtained. This is because it was not possible (Chem. Rev. 58, 808 (1958) (Non-Patent Document 1)).

Japanese Unexamined Patent Publication No. 58-49792 (Patent Document 1) describes an ethylene / allyl acetate copolymer and an ethylene-allyl acetate-vinyl acetate ternary copolymer as a hydrocarbon oil composition. The synthesis method was a radical polymerization method, and according to Examples, only a low molecular weight substance having an intrinsic viscosity of about 0.12 dl / g was obtained.

Japanese Unexamined Patent Publication No. 2004-256620 (Patent Document 2) and Polym. Adv. Technol. , 18, 953 (2007) (Non-Patent Document 2) describes a method of adding blended acid or Lewis acid for the purpose of increasing the molecular weight of the obtained polymer in the radical polymerization of allyl acetate or allyl alcohol. ing. However, in these polymerization methods, it is necessary to add Bronsted acid or Lewis acid in an equivalent amount or more with respect to the monomer, and there is room for improvement in terms of production cost and acid removal. In addition, since low molecular weight oligomers are also by-produced in these polymerization systems, dialysis membranes are used for polymer isolation, which leaves a big problem for industrial application.

Japanese Unexamined Patent Publication No. 2011-68881 (Patent Document 3) and J. Am. Am. Chem. Soc. , 133, 1232 (2011) (Non-Patent Document 3) describes the copolymerization of ethylene with allyl acetate or allyl alcohol using the organic metal complex of Group 10 of the periodic table as a coordination polymerization catalyst. By these polymerization methods, an ethylene-allyl acetate copolymer or an ethylene-allyl alcohol copolymer having a number average molecular weight Mn of about tens of thousands has been obtained. However, these methods use an expensive metal complex as a polymerization catalyst, and only a polymer in which only a few mol% of allyl monomer is incorporated has been obtained, which leaves a problem in industrialization. ..

In polymerization in which only low molecular weight substances at the oligomer level can be obtained, a method of copolymerizing a dialkenyl monomer or the like is known for the purpose of improving the molecular weight. Applying this method to allyl monomers can be described in Pure & Appl. Chem. , 61, 2051 (1989) (Non-Patent Document 4), and Chromatographia, 11, 137 (1978) (Non-Patent Document 5). However, since the copolymer is used as a stationary phase in gas chromatography in all the documents, it is a polymer gel having a network structure in which the copolymer is highly crosslinked and the polymer chains are intricately entangled. It is clear that there is. Since such a polymer gel does not dissolve in a solvent, it is inferior in moldability in injection molding, cast molding, etc., and further, the mechanical strength of the molded product is low. The allyl monomer content of the copolymers obtained in Non-Patent Document 4 and Non-Patent Document 5 is 40% or 10%, respectively. Such a copolymer having a low content of allyl monomer cannot express useful physical properties derived from allyl monomer such as gas barrier property. Therefore, industrial production of a polar group-containing allyl polymer using this method has not been realized so far.

Japanese Unexamined Patent Publication No. 58-49792 Japanese Unexamined Patent Publication No. 2004-256620 Japanese Unexamined Patent Publication No. 2011-68881

Chem. Rev. 58,808 (1958) Polym. Adv. Technol. , 18, 953 (2007) J. Am. Chem. Soc. , 133, 1232 (2011) Pure & Appl. Chem. , 61, 2051 (1989) Chromatographia, 11, 137 (1978)

An object of the present invention is to provide a polar group-containing 2-alkenyl monomer copolymer having a high molecular weight and being soluble in a predetermined solvent, and a method for producing the same.

As a result of diligent studies to solve the above problems, the present inventors have a novel structure by performing radical copolymerization of a polar group-containing 2-alkenyl monomer and a dialkenyl monomer, and have various applications. We have found that it is possible to provide a 2-alkenyl monomer-dialkenyl monomer copolymer containing a polar group having a high molecular weight, and have completed the present invention. In the present specification, the "polar group-containing 2-alkenyl monomer-dialkenyl monomer copolymer" also includes a ternary or higher copolymer containing another monomer unit as a minor component.

（式中、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、それぞれ独立に、水素原子又は炭素原子数１～３のアルキル基を表し、Ｘは酸素原子を含んでいてもよい、炭素原子数１～２０の２価の有機基を表し、ｌ、ｍ、及びｎはそれぞれのモノマー構造単位のモル比を表す数値であり、ｌ又はｍのいずれか一方が０であってもよい。）
で示されるモノマー構造単位を有する共重合体であって、以下の要件（Ａ）、（Ｂ）、及び（Ｃ）を満たす共重合体。
（Ａ）式（１）で示されるモノマー構造単位のモル比ｌ、式（２）で示されるモノマー構造単位のモル比ｍ、及び式（３）で示されるジアルケニルモノマー構造単位のモル比ｎが、次式：
０．１≦［ｎ／（ｌ＋ｍ＋ｎ）］×１００≦６５の関係を満たす。
（Ｂ）重量平均分子量Ｍｗが１０，０００～１，０００，０００である。
（Ｃ）ゲル化しておらず、所定の溶媒に溶解する。
［２］
０．１≦［ｎ／（ｌ＋ｍ＋ｎ）］×１００≦２０の関係を満たす、［１］に記載の共重合体。
［３］
Ｘが、－Ｃ_６Ｈ_４－である［１］又は［２］のいずれかに記載の共重合体。
［４］
Ｒ^１、Ｒ^２及びＲ^４が水素原子である［１］～［３］のいずれかに記載の共重合体。
［５］
Ｒ^３がメチル基である［１］～［４］のいずれかに記載の共重合体。
［６］
ｌ又はｍのいずれか一方が０である［１］～［５］のいずれかに記載の共重合体。
［７］
前記所定の溶媒が、ベンゼン、トルエン、キシレン、クロロホルム、塩化メチレン、四塩化炭素、ジクロロエタン、テトラクロロエタン、クロロベンゼン、ジクロロベンゼン、トリクロロベンゼン、Ｎ，Ｎ－ジメチルホルムアミド、Ｎ，Ｎ－ジメチルアセトアミド、ジメチルスルホキシド、テトラヒドロフラン、メタノール、エタノール、イソプロパノール、ｎ－プロパノール、２－ブタノール、ｎ－ブタノール、エチルセロソルブ、及びブチルセロソルブからなる群より選ばれる少なくとも一種である［１］～［６］のいずれかに記載の共重合体。
［８］
式（４）

（式中、Ｒ^２及びＲ^３は、それぞれ独立に、水素原子又は炭素原子数１～３のアルキル基を表す。）
で示される２－アルケニルエステル化合物、及び式（５）

（式中、Ｒ^４は、それぞれ独立に、水素原子又は炭素原子数１～３のアルキル基を表し、Ｘは酸素原子を含んでいてもよい、炭素原子数１～２０の２価の有機基を表す。）
で示されるジアルケニル化合物をラジカル重合開始剤の存在下で共重合することを含む、式（２）及び式（３）

（式中、Ｒ^２、Ｒ^３、及びＲ^４は、それぞれ独立に、水素原子又は炭素原子数１～３のアルキル基を表し、Ｘは酸素原子を含んでいてもよい、炭素原子数１～２０の２価の有機基を表し、ｍ及びｎはそれぞれのモノマー構造単位のモル比を表す数値である。）
で示されるモノマー構造単位を有する共重合体の製造方法。
［９］
式（４）

（式中、Ｒ^２及びＲ^３は、それぞれ独立に、水素原子又は炭素原子数１～３のアルキル基を表す。）
で示される２－アルケニルエステル化合物、及び式（５）

（式中、Ｒ^４は、それぞれ独立に、水素原子又は炭素原子数１～３のアルキル基を表し、Ｘは酸素原子を含んでいてもよい、炭素原子数１～２０の２価の有機基を表す。）
で示されるジアルケニル化合物をラジカル重合開始剤の存在下で共重合した後に、触媒存在下、アルコール溶媒中でけん化することを含む、式（１）、式（２）及び式（３）

（式中、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、それぞれ独立に、水素原子又は炭素原子数１～３のアルキル基を表し、但しＲ^１とＲ^２は同一であり、Ｘは酸素原子を含んでいてもよい、炭素原子数１～２０の２価の有機基を表し、ｌ、ｍ、及びｎはそれぞれのモノマー構造単位のモル比を表す数値であり、ｍは０であってもよい。）
で示されるモノマー構造単位を有する共重合体の製造方法。
［１０］
式（６）

（式中、Ｒ^１は、水素原子又は炭素原子数１～３のアルキル基を表す。）
で示される２－アルケニルアルコール化合物、及び式（５）

（式中、Ｒ^４は、それぞれ独立に、水素原子又は炭素原子数１～３のアルキル基を表し、Ｘは酸素原子を含んでいてもよい、炭素原子数１～２０の２価の有機基を表す。）
で示されるジアルケニル化合物をラジカル重合開始剤の存在下で共重合することを含む、式（１）及び式（３）

（式中、Ｒ^１及びＲ^４は、それぞれ独立に、水素原子又は炭素原子数１～３のアルキル基を表し、Ｘは酸素原子を含んでいてもよい、炭素原子数１～２０の２価の有機基を表し、ｌ及びｎはそれぞれのモノマー構造単位のモル比を表す数値である。）
で示されるモノマー構造単位を有する共重合体の製造方法。
［１１］
ｍが０である［９］に記載の共重合体の製造方法。
［１２］
Ｒ^１、Ｒ^２及びＲ^４が水素原子である［８］～［１１］のいずれかに記載の共重合体の製造方法。
［１３］
Ｒ^３がメチル基である［８］～［１２］のいずれかに記載の共重合体の製造方法。
［１４］
前記ラジカル重合開始剤の１０時間半減期温度が５０℃以下である、［８］～［１３］のいずれかに記載の共重合体の製造方法。
［１５］
重合温度が２０～７０℃の範囲である、［８］～［１４］のいずれかに記載の共重合体の製造方法。
［１６］
式（４）で示される２－アルケニルエステル化合物と式（６）で示される２－アルケニルアルコール化合物の合計モル量をｘ、式（５）で示されるジアルケニル化合物のモル量をｙとしたときに、次式：
０．１≦［ｙ／（ｘ＋ｙ）］×１００≦６５
の範囲でラジカル重合を行うことを特徴とする、［８］～［１５］のいずれかに記載の共重合体の製造方法。
［１７］
少なくとも１層のプラスチックフィルムと、［１］～［７］のいずれかに記載の共重合体を含む少なくとも１層の酸素バリア層とを含む、酸素バリア性積層体。
［１８］
前記プラスチックフィルムがポリプロピレンフィルムである［１７］に記載の酸素バリア性積層体。
［１９］
プラスチックフィルムに、［１］～［７］のいずれかに記載の共重合体を溶媒に溶解した溶液を塗布又は流延し、乾燥することを含む酸素バリア性積層体の製造方法。
［２０］
前記溶媒がアルコールである［１９］に記載の酸素バリア性積層体の製造方法。
［２１］
前記溶媒がエタノールであり、前記プラスチックフィルムがポリプロピレンフィルムである［１９］又は［２０］のいずれかに記載の酸素バリア性積層体の製造方法。 That is, the present invention relates to the following [1] to [21].
[1]
Equation (1), Equation (2), and Equation (3)

(In the formula, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X may contain an oxygen atom and may contain an oxygen atom. It represents a divalent organic group of 1 to 20, and l, m, and n are numerical values representing the molar ratio of each monomer structural unit, and either l or m may be 0).
A copolymer having a monomer structural unit represented by (1) and satisfying the following requirements (A), (B), and (C).
(A) The molar ratio l of the monomer structural unit represented by the formula (1), the molar ratio m of the monomer structural unit represented by the formula (2), and the molar ratio n of the dialkenyl monomer structural unit represented by the formula (3). However, the following formula:
The relationship of 0.1 ≦ [n / (l + m + n)] × 100 ≦ 65 is satisfied.
(B) The weight average molecular weight Mw is 10,000 to 1,000,000.
(C) It is not gelled and dissolves in a predetermined solvent.
[2]
The copolymer according to [1], which satisfies the relationship of 0.1 ≦ [n / (l + m + n)] × 100 ≦ 20.
[3]
The copolymer according to any one of [1] or [ ₂ ], wherein X is _−C6 H4-.
[4]
The copolymer according to any one of [1] to [3], wherein R ¹ , R ² and R ⁴ are hydrogen atoms.
[5]
The copolymer according to any one of [1] to [4], wherein R ³ is a methyl group.
[6]
The copolymer according to any one of [1] to [5], wherein either l or m is 0.
[7]
The predetermined solvent is benzene, toluene, xylene, chloroform, methylene chloride, carbon tetrachloride, dichloroethane, tetrachloroethane, chlorobenzene, dichlorobenzene, trichlorobenzene, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide. , Tetrahydrofuran, methanol, ethanol, isopropanol, n-propanol, 2-butanol, n-butanol, ethyl cellosolve, and butyl cellosolve, which is at least one selected from the group [1] to [6]. Polymer.
[8]
Equation (4)

(In the formula, R ² and R ³ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.)
2-alkenyl ester compound represented by, and formula (5)

(In the formula, R ⁴ independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X is a divalent organic group having 1 to 20 carbon atoms which may contain an oxygen atom. Represents.)
Formulations (2) and (3), which include copolymerizing the dialkenyl compound represented by (1) in the presence of a radical polymerization initiator.

(In the formula, R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X may contain an oxygen atom and have 1 to 1 carbon atoms. It represents 20 divalent organic groups, and m and n are numerical values representing the molar ratio of each monomer structural unit.)
A method for producing a copolymer having a monomer structural unit represented by.
[9]
Equation (4)

(In the formula, R ² and R ³ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.)
2-alkenyl ester compound represented by, and formula (5)

(In the formula, R ⁴ independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X is a divalent organic group having 1 to 20 carbon atoms which may contain an oxygen atom. Represents.)
The dialkenyl compound represented by the above formulas (1), (2) and (3), which comprises copolymerizing in the presence of a radical polymerization initiator and then saponifying in an alcohol solvent in the presence of a catalyst.

(In the formula, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, where R ¹ and R ² are the same, and X is oxygen. It represents a divalent organic group having 1 to 20 carbon atoms which may contain an atom, l, m, and n are numerical values representing the molar ratio of each monomer structural unit, and m is 0. May be good.)
A method for producing a copolymer having a monomer structural unit represented by.
[10]
Equation (6)

(In the formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.)
2-Alkenyl alcohol compound represented by, and formula (5)

(In the formula, R ⁴ independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X is a divalent organic group having 1 to 20 carbon atoms which may contain an oxygen atom. Represents.)
Formulations (1) and (3), which include copolymerizing the dialkenyl compound represented by (1) in the presence of a radical polymerization initiator.

(In the formula, R ¹ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X may contain an oxygen atom and are divalent with 1 to 20 carbon atoms. L and n are numerical values representing the molar ratio of each monomer structural unit.)
A method for producing a copolymer having a monomer structural unit represented by.
[11]
The method for producing a copolymer according to [9], wherein m is 0.
[12]
The method for producing a copolymer according to any one of [8] to [11], wherein R ¹ , R ² and R ⁴ are hydrogen atoms.
[13]
The method for producing a copolymer according to any one of [8] to [12], wherein R ³ is a methyl group.
[14]
The method for producing a copolymer according to any one of [8] to [13], wherein the radical polymerization initiator has a 10-hour half-life temperature of 50 ° C. or lower.
[15]
The method for producing a copolymer according to any one of [8] to [14], wherein the polymerization temperature is in the range of 20 to 70 ° C.
[16]
When the total molar amount of the 2-alkenyl ester compound represented by the formula (4) and the 2-alkenyl alcohol compound represented by the formula (6) is x, and the molar amount of the dialkenyl compound represented by the formula (5) is y. , The following formula:
0.1 ≦ [y / (x + y)] × 100 ≦ 65
The method for producing a copolymer according to any one of [8] to [15], which comprises performing radical polymerization in the range of [8] to [15].
[17]
An oxygen barrier laminate comprising at least one layer of a plastic film and at least one oxygen barrier layer containing the copolymer according to any one of [1] to [7].
[18]
The oxygen barrier laminate according to [17], wherein the plastic film is a polypropylene film.
[19]
A method for producing an oxygen barrier laminate, which comprises applying or casting a solution in which the copolymer according to any one of [1] to [7] is dissolved in a solvent to a plastic film and drying the plastic film.
[20]
The method for producing an oxygen barrier laminate according to [19], wherein the solvent is alcohol.
[21]
The method for producing an oxygen barrier laminate according to any one of [19] or [20], wherein the solvent is ethanol and the plastic film is a polypropylene film.

According to the present invention, it is possible to obtain a polar group-containing 2-alkenyl monomer-dialkenyl monomer copolymer having a high molecular weight and being soluble in a predetermined solvent, which has been difficult to produce in the past.

Since the polar group-containing 2-alkenyl monomer-dialkenyl monomer copolymer of the present invention has an ester structure and a polar functional structure such as a hydroxyl group, it has a surface such as adhesiveness and printability added to polyolefin or the like. In addition to property modifiers, dispersants such as non-polar polyolefin and other highly polar resins, and dispersants such as pigments, paints, inks, adhesives, binders, plasticizers, lubricants, lubricants, and surfactants. It can be used as an activator or the like. Further, since the copolymer of the present invention is soluble in a solvent, it can be easily formed into a film or a sheet, and can be applied to food packaging materials, gasoline tanks and the like.

6 is a ¹ H-NMR spectrum of the copolymer obtained in Example 3. 3 is an SEC chromatogram of the copolymer obtained in Example 3. 6 is a ¹ H-NMR spectrum of the saponified product obtained in Example 8.

Hereinafter, preferred embodiments of the present invention will be described, but the present invention is not limited to these embodiments.

（式中、Ｒ^１、Ｒ^２、Ｒ^３及びＲ^４は、それぞれ独立に、水素原子又は炭素原子数１～３のアルキル基を表し、Ｘは酸素原子を含んでいてもよい、炭素原子数１～２０の２価の有機基を表し、ｌ、ｍ、及びｎはそれぞれのモノマー構造単位のモル比を表す数値であり、ｌ又はｍのいずれか一方が０であってもよい。）
で示されるモノマー構造単位を有する共重合体である。共重合体は必要に応じて第四のモノマー構造単位を含んでいてもよい。 1. 1. Polar group-containing 2-alkenyl monomer-dialkenyl monomer copolymer The polar group-containing 2-alkenyl monomer-dialkenyl monomer copolymer of one embodiment has the formulas (1), (2), and (3).

(In the formula, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X may contain an oxygen atom and may contain an oxygen atom. It represents a divalent organic group of 1 to 20, and l, m, and n are numerical values representing the molar ratio of each monomer structural unit, and either l or m may be 0).
It is a copolymer having a monomer structural unit represented by. The copolymer may optionally contain a fourth monomer structural unit.

R ¹ , R ² , and R ⁴ in the formula (1), the formula (2), and the formula (3) represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and each of them may be different.

Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Among these, as ^R1 , ^R2 , and ^R4 , a hydrogen atom or a methyl group is preferable, and from the viewpoint of availability of raw materials, a hydrogen atom is particularly preferable.

R ³ in the formula (2) represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Among these, as R3 ^, a methyl group or an ethyl group is preferable, and from the viewpoint of availability of raw materials, a methyl group is particularly preferable.

X in the formula (3) represents a divalent organic group having 1 to 20 carbon atoms, which may contain an oxygen atom.

Examples of the divalent organic group include an alkylene group and an arylene group. Examples of the divalent organic group containing an oxygen atom include a group in which two carbonyloxy groups (-C (= O) -O-) are bonded to an alkylene group or an arylene group.

Examples of divalent organic groups are -CH 2-, -CH ₂ CH _2- , -CH ₂ CH ₂ CH _2- , -CH ₂ CH ₍ CH ₃ ) CH _2- , -C ₆ H _4- , -C ₆ H ₄ -C ₆ H _4- , -C (= O) -O- (CH ₂ ) ₂ -OC (= O)-, -C (= O) -O- (CH ₂ ) ₂ -O- (CH ₂ ) ₂ -OC (= O)-and-C (= O) -O- (C ₆ H ₄ ) -OC (= O)-are examples. Among these, as X, -C ₆ H _4- (phenylene group) or -C (= O) -O- (CH ₂ ) ₂ -OC (= O)-is preferable, and -C ₆ H ₄ -Is particularly preferable. When X is −C ₆ H4-, _each of X in the copolymer may be an o-substituted product, an m-substituted product, or a p-substituted product independently.

The copolymer of one embodiment satisfies the following requirements (A), (B), and (C).
(A) The molar ratio l of the monomer structural unit represented by the formula (1), the molar ratio m of the monomer structural unit represented by the formula (2), and the molar ratio n of the dialkenyl monomer structural unit represented by the formula (3). However, the following formula:
The relationship of 0.1 ≦ [n / (l + m + n)] × 100 ≦ 65 is satisfied.
(B) The weight average molecular weight Mw is 10,000 to 1,000,000.
(C) It is not gelled and dissolves in a predetermined solvent.

(A) Molar ratio of monomer structural unit The molar ratio l, the molar ratio m, and the molar ratio n satisfy the relationship of the following equation.
0.1 ≦ [n / (l + m + n)] × 100 ≦ 65

When [n / (l + m + n)] × 100 is 0.1 or more, the molecular weight of the copolymer can be improved and the strength of the molded product can be increased. When [n / (l + m + n)] × 100 is 65 or less, the solubility in a predetermined solvent can be enhanced without gelling the copolymer. [N / (l + m + n)] × 100 is preferably 1 or more, and more preferably 5 or more. [N / (l + m + n)] × 100 is preferably 20 or less, more preferably 15 or less. The value of [n / (l + m + n)] × 100 is determined by the ¹ H-NMR method described in Examples. The formulas (1), (2), and l, m, and n of the formula (3) simply indicate the amount ratios of the corresponding monomers, and the formulas (1), (2), and (3). ) Does not necessarily mean that l, m, and n monomer structural units are continuously bonded, respectively.

In one embodiment, either l or m is 0.

(B) Weight Average Molecular Weight The weight average molecular weight Mw of the copolymer of one embodiment is 10,000 to 1,000,000. The Mw is preferably 10,000 to 500,000, more preferably 10,000 to 100,000, from the viewpoint of the balance between the moldability and the strength of the molded product. If Mw is less than 10,000, the strength of the molded product decreases. If Mw exceeds 100,000, the solution viscosity or melt viscosity is too high and molding becomes difficult. Mw is determined by the method according to the GPC described in the examples.

(C) It is not gelled and dissolves in a predetermined solvent.
The term "gelled" refers to the presence of a component that is insoluble in any solvent due to the presence of a crosslinked structure. In the gelled copolymer, even if the main chain portion tries to dissolve in a good solvent, the crosslinked structure portion only swells and does not dissolve. "It is not gelled and dissolves in a predetermined solvent" means that all the components of the copolymer are dissolved if an appropriate good solvent and temperature are selected. Whether or not it has dissolved is determined by visual observation.

The copolymer is preferably dissolved in a predetermined solvent having a solid content concentration of 0.1 to 10% by mass and a temperature of 20 to 30 ° C.

The predetermined solvent is a good solvent for the copolymer. Specific examples of the predetermined solvent include aromatic hydrocarbons such as benzene, toluene and xylene, halogenated aliphatic hydrocarbons such as chloroform, methylene chloride, carbon tetrachloride, dichloroethane and tetrachloroethane, chlorobenzene and dichlorobenzene. Halogenated aromatic hydrocarbons such as trichlorobenzene, nitrogen-containing solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, sulfur-containing solvents such as dimethylsulfoxide, cyclic ether solvents such as tetrahydrofuran, methanol, ethanol, isopropanol. , N-propanol, 2-butanol, n-butanol and the like alcohol solvents, ethyl cellosolve, butyl cellosolve and the like cellosolve solvents and the like.

The good solvent as the predetermined solvent preferably contains benzene, toluene, xylene, chloroform, methylene chloride, N, N-dimethylformamide, or dimethyl sulfoxide.

The predetermined solvent may be a single solvent or a mixed solvent of two or more kinds. In the case of a mixed solvent, the optimum solvent composition differs depending on the molar ratio l, m and n of each monomer structural unit in the copolymer, but it is preferable to increase the ratio of the alcohol solvent or the cellosolve solvent as l is larger. ..

When dissolving the copolymer in the solvent, the solvent may be heated for the purpose of promoting the dissolution. The heating temperature is preferably in the range of 40 to 200 ° C, more preferably in the range of 40 to 150 ° C, and particularly preferably in the range of 40 to 100 ° C from the viewpoint of avoiding decomposition of the copolymer.

2. 2. Method for Producing Polar Group-Containing 2-alkenyl Monomer-Dialkenyl Monomer Copolymer The polar group-containing 2-alkenyl monomer-dialkenyl monomer copolymer of some embodiments can be produced by the following method.
(A) The compound represented by the formula (4), the formula (5), and the formula (6), and if necessary, other monomers corresponding to the fourth monomer unit are added to the compound represented by the formula (6) in the presence of a radical polymerization initiator described later. Copolymerize with.
(B) The compounds represented by the formulas (4) and (5) and, if necessary, other monomers corresponding to the fourth monomer unit are copolymerized in the presence of a radical polymerization initiator described later.
(C) The copolymer obtained by copolymerizing the compounds represented by the formulas (4) and (5) and, if necessary, other monomers corresponding to the fourth monomer unit, will be described later. In the presence of the catalyst of, the saponification reaction is carried out in an alcohol solvent.
(D) The compound represented by the formulas (6) and (5) and, if necessary, other monomers corresponding to the fourth monomer unit are copolymerized in the presence of a radical polymerization initiator described later.

In one embodiment, in the copolymer produced by the method (C), the molar ratio m of the monomer structural unit represented by the formula (2) is 0. In this embodiment, the saponification reaction is completely in progress.

で示される２－アルケニルエステル化合物である。 In the copolymer, the monomer that is the source of the monomer structural unit represented by the formula (2) is the formula (4).

It is a 2-alkenyl ester compound represented by.

R ² in the formula (4) represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Among these, as R ² , a hydrogen atom or a methyl group is preferable, and from the viewpoint of availability of a raw material, a hydrogen atom is particularly preferable.

R ³ in the formula (4) represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Among these, as R3 ^, a methyl group or an ethyl group is preferable, and from the viewpoint of availability of raw materials, a methyl group is particularly preferable.

で示される２－アルケニルアルコール化合物である。 In the copolymer, the monomer that is the source of the monomer structural unit represented by the formula (1) is the formula (6).

It is a 2-alkenyl alcohol compound represented by.

R ¹ in the formula (6) represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Among these, as R ¹ , a hydrogen atom or a methyl group is preferable, and from the viewpoint of availability of a raw material, a hydrogen atom is particularly preferable.

で示される２－アルケニルエステル化合物を重合した後に、後述の触媒を使用して、アルコール溶媒中で加水分解（けん化反応）を行うことでも得ることができる。 The monomer structural unit represented by the formula (1) is the above formula (4).

It can also be obtained by polymerizing the 2-alkenyl ester compound shown in (1) and then hydrolyzing (saponifying reaction) in an alcohol solvent using a catalyst described below.

R ² in the formula (4) represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ¹ is a monomer unit represented by the formula (1) and R ² is a monomer unit represented by the formula (2). Is derived from R ² in the formula (4), so that R ¹ and R ² are the same.

Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Among these, as R ² , a hydrogen atom or a methyl group is preferable, and from the viewpoint of availability of a raw material, a hydrogen atom is particularly preferable.

R ³ in the formula (4) represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Among these, as R3 ^, a methyl group or an ethyl group is preferable, and from the viewpoint of availability of raw materials, a methyl group is particularly preferable.

The monomer represented by the formula (4) and the monomer represented by the formula (6) may be mixed and polymerized. From the viewpoint of improving the reaction rate, it is preferable to polymerize only the monomer represented by the formula (4) without using the monomer represented by the formula (6).

で示されるジアルケニル化合物である。 In the copolymer, the dialkenyl monomer which is the source of the monomer structural unit represented by the formula (3) is the formula (5).

It is a dialkenyl compound represented by.

R ⁴ in the formula (5) independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group. Among these, as ^R4 , a hydrogen atom or a methyl group is preferable, and from the viewpoint of availability of a raw material, a hydrogen atom is particularly preferable.

X in the formula (5) represents a divalent organic group having 1 to 20 carbon atoms, which may contain an oxygen atom.

Examples of the divalent organic group include an alkylene group and an arylene group. Examples of the divalent organic group containing an oxygen atom include a group in which two carbonyloxy groups (-C (= O) -O-) are bonded to an alkylene group or an arylene group.

Examples of divalent organic groups are -CH 2-, -CH ₂ CH _2- , -CH ₂ CH ₂ CH _2- , -CH ₂ CH ₍ CH ₃ ) CH _2- , -C ₆ H _4- , -C ₆ H ₄ -C ₆ H _4- , -C (= O) -O- (CH ₂ ) ₂ -OC (= O)-, -C (= O) -O- (CH ₂ ) ₂ -O- (CH ₂ ) ₂ -OC (= O)-and-C (= O) -O- (C ₆ H ₄ ) -OC (= O)-are examples. Among these, as X, -C ₆ H _4- (phenylene group) or -C (= O) -O- (CH ₂ ) ₂ -OC (= O)-is preferable, and -C ₆ H ₄ -Is particularly preferable. When X is −C ₆ H ₄ −, it may be an o-substituent, an m-substituent, or a p-substituent.

The dialkenyl monomer may be used alone or in combination of two or more.

Examples of the dialkenyl monomer represented by the formula (5) include o-divinylbenzene, m-divinylbenzene, p-divinylbenzene, ethylene glycol dimethacrylate, and diethylene glycol diacrylate. Among these, p-divinylbenzene and ethylene glycol dimethacrylate are preferable.

In the method for producing a copolymer of one embodiment, other monomers corresponding to the fourth monomer unit may be copolymerized, if necessary. Other monomers include α-olefins such as propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, 1-octene, 1-norbornene, 1-decene and styrene; Cyclic olefins such as norbornene, cyclopentene and cyclohexene; olefins having polar groups such as acrylic acid ester, methacrylic acid ester, vinyl acetate, vinyl ether, acrylonitrile and achlorine can be mentioned. These may be polymerized by combining two or more kinds. The content of other monomers contained in the copolymer is preferably less than 5 mol%, more preferably less than 2 mol%.

In the method for producing a copolymer of one embodiment, a known radical polymerization initiator can be used.

Examples of the radical polymerization initiator include azo compounds such as 2,2'-azobisisobutyronitrile and 2,2'-azobis (2,4-dimethylvaleronitrile); methylethylketone peroxide, methylisobutylketone peroxide and the like. Ketone peroxide compounds; diacyl peroxide compounds such as benzoyl peroxide and lauroyl peroxide; dialkyl peroxide compounds such as dicumylper oxide and t-butylcumylperoxide; 1,1-di (t-hexylperoxy). Peroxyketal compounds such as -3,3,5-trimethylcyclohexane; alkylperoxy such as t-butylperoxypivalate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate. Ester compounds; peroxycarbonate compounds such as diisopropyl peroxydicarbonate, di-sec-butylperoxydicarbonate, t-butylperoxyisoproprucarbonate, di (4-t-butylcyclohexyl) peroxydicarbonate; peroxidation Examples thereof include, but are not limited to, thermal radical polymerization initiators such as hydrogen. These radical polymerization initiators may be used alone or in combination of two or more.

The 10-hour half-life temperature of the radical polymerization initiator is preferably 50 ° C. or lower. In particular, the radical polymerization initiator is preferably a di (4-t-butylcyclohexyl) peroxydicarbonate having a 10-hour half-life temperature of 48 ° C. If the 10-hour half-life temperature exceeds 50 ° C., the molecular weight of the copolymer may become too low.

The amount of the radical polymerization initiator used can be determined based on the reaction temperature and the composition ratio of each monomer. The amount of the radical polymerization initiator used is preferably 0.1 to 15 mol%, particularly preferably 0.5 to 10 mol%, based on the total amount of the radically polymerizable monomers. When the amount of the radical polymerization initiator added is 0.1 mol% or more, the progress of the polymerization reaction can be promoted. When the amount of the radical polymerization initiator added is 15 mol% or less, a copolymer having a desired molecular weight can be economically produced.

In the method for producing a copolymer of one embodiment, the polymerization temperature is preferably in the range of 20 to 70 ° C, and particularly preferably in the range of 30 to 65 ° C. When the polymerization temperature is 20 ° C. or higher, the polymerization reaction can proceed at an economical rate. When the polymerization temperature is 70 ° C. or lower, the chain transfer rate to the 2-alkenyl monomer can be suppressed to produce a copolymer having a desired molecular weight.

In the method for producing a copolymer of one embodiment, the total molar amount of the 2-alkenyl ester compound represented by the formula (4) and the 2-alkenyl alcohol compound represented by the formula (6) is represented by x and the formula (5). When the molar amount of the dialkenyl compound is y, the following formula:
0.1 ≦ [y / (x + y)] × 100 ≦ 65
It is preferable to carry out radical polymerization in the range of
0.5 ≦ [y / (x + y)] × 100 ≦ 20
It is particularly preferable to carry out radical polymerization in the range of.

When the value of [y / (x + y)] × 100 is 0.1 or more, the molecular weight of the copolymer can be increased to a desired degree, and when it is 65 or less, gelation of the copolymer is suppressed. can do.

The polymerization method of the copolymer is not particularly limited, and generally used methods such as bulk polymerization, solution polymerization, suspension polymerization, or vapor phase polymerization can be used. Bulk polymerization and solution polymerization are particularly preferable. The polymerization mode may be a batch mode, a continuous mode, a one-stage polymerization, or a multi-stage polymerization. Monomers may be added within the range of the above-mentioned monomer charging ratio. A radical polymerization initiator may be added.

The polymerization time can be appropriately adjusted depending on the polymerization method, the polymerization mode, the half-life of the initiator and the like. The polymerization time may be as short as several minutes or as long as several thousand hours.

In order to prevent a decrease in the starting efficiency, it is preferable that the atmosphere in the polymerization system is filled with an inert gas such as nitrogen gas or argon so that air other than the monomer, oxygen gas, moisture and the like are not mixed. It is also preferable to fill the gas phase with the monomer vapor by charging a glass ampoule or the like with a monomer or a radical polymerization initiator and performing freeze degassing.

In the case of solution polymerization, an inert solvent can be used in addition to the monomer. The inert solvent is not particularly limited, and is, for example, an aliphatic hydrocarbon such as isobutane, pentane, hexane, or cyclohexane, an aromatic hydrocarbon such as benzene, toluene, or xylene, chloroform, methylene chloride, carbon tetrachloride, dichloroethane, or tetra. Halogened aliphatic hydrocarbons such as chloroethane, halogenated aromatic hydrocarbons such as chlorobenzene, dichlorobenzene and trichlorobenzene, aliphatic esters such as methyl acetate and ethyl acetate, aromatic esters such as methyl benzoate and ethyl benzoate, And aliphatic ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and t-butyl methyl ketone.

After completion of the polymerization reaction, the product copolymer should be post-treated by a known operation or treatment method (for example, neutralization, solvent extraction, washing with water, liquid separation, solvent distillation, freeze-drying, reprecipitation, etc.). May be isolated by.

The saponification reaction of the copolymer in an alcohol solvent can be carried out by a known method.

The saponification reaction can be carried out in the presence of an acidic or basic catalyst in a solvent containing an alcohol. Examples of the acidic catalyst include hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid, tolfluoroacetic acid, trichloroacetic acid, tolfluoromethanesulfonic acid, methanesulfonic acid, and p-toluenesulfonic acid, from the viewpoint of industrial availability. , Acidic acid, sulfuric acid, or acetic acid is preferred, and hydrochloric acid is more preferred. Examples of the basic catalyst include sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium methoxide, and sodium ethoxydo, and from the viewpoint of industrial availability, sodium methoxyde, sodium hydroxide, or Potassium hydroxide is preferred, sodium methoxydo or sodium hydroxide is more preferred. Examples of the alcohol include methanol, ethanol, isopropanol, n-propanol, 2-butanol, and n-butanol. From the viewpoint of industrial availability, methanol or ethanol is preferable, and methanol is more preferable. The solvent containing alcohol may be alcohol alone or a mixture with other solvents. Examples of other solvents include toluene, xylene, cyclohexane, n-hexane, ethyl acetate, methyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, methyl ethyl ketone, tetrahydrofuran, methylene chloride, chloroform, dichlorobenzene, and water. Can be mentioned.

The copolymer can be molded into pellets, films, sheets, etc. using ordinary thermoplastic resin molding methods and conditions.

The copolymer itself can be made into a product by molding such as injection molding, extrusion molding, and film molding. The copolymer is used as a modifier for surface properties such as adhesiveness and printability added to polyolefins, a compatibilizer for non-polar polyolefins and other highly polar resins, and a dispersant for pigments and the like. You can also do it. Copolymers can also be used as paints, inks, adhesives, binders, plasticizers, lubricants, lubricants, surfactants and the like.

3. 3. Oxygen Barrier Laminate A oxygen barrier laminate can be produced by laminating at least one oxygen barrier layer containing the copolymer of one embodiment on at least one plastic film.

From the viewpoint of improving the oxygen barrier property, the molar ratio l of the monomer structural unit represented by the formula (1) and the molar ratio m of the monomer structural unit represented by the formula (2) are as follows.
90 ≦ [l / (l + m)] × 100 ≦ 100
It is preferable to satisfy the relationship of
95 ≦ [l / (l + m)] × 100 ≦ 100
It is more preferable to satisfy the relationship of
98 ≦ [l / (l + m)] × 100 ≦ 100
It is particularly preferable to satisfy the relationship of.
When [l / (l + m)] × 100 is less than 90, the oxygen barrier property tends to decrease.

The oxygen barrier laminate of one embodiment can be produced by using a molding method known in the general polymer molding processing field. Specifically, methods such as solution casting, T-die molding, inflation molding, dry laminating molding, extrusion coating, and coextrusion molding can be adopted. Among these, solution casting is preferable from the viewpoint of ease of film formation and simplification of the process.

Solution casting is a method of forming a laminate by applying or casting a solution in which a copolymer is dissolved in a solvent onto a plastic film and then drying the solution.

As the solvent, a good solvent of the copolymer can be used. From the viewpoint of ease of distillation in the drying step and safety, alcohol and glycol monoether are preferable, and ethanol and ethyl cellosolve are particularly preferable. These solvents may be used alone or in combination.

The solid content concentration (concentration of components other than the solvent) of the solution is not particularly limited, but is preferably 1 to 50% by mass, more preferably 3 to 30% by mass, and particularly preferably 5 to 20% by mass. When the solid content concentration is 1% by mass or more, the time required for solvent distillation in the drying step can be shortened, and the production cost can be suppressed. When the solid content concentration is 20% by mass or less, the viscosity of the solution can be set within an appropriate range, and the occurrence of thickness unevenness or streaks during coating or casting can be suppressed.

If necessary, an additive may be added to the copolymer solution as long as the oxygen barrier property is not impaired. Additives include, for example, stabilizers (antioxidants, heat stabilizers, UV absorbers, etc.), plasticizers, antioxidants, lubricants, antiblocking agents, colorants, fillers, crystal nucleating agents, inorganic fillers, etc. And plate-like inorganic compounds. These additives may be used alone or in combination of two or more.

The method of applying or spreading the copolymer solution is not particularly limited, but is limited to bar coater coating, Mayer bar coating, air knife coating, gravure coating, reverse gravure coating, microgravure coating, and microreverse coating. Known methods such as gravure coater coating, die coater coating, slot die coater coating, vacuum die coater coating, dip coating, spin coating coating, spray coating, and brush coating can be used.

The drying method is not particularly limited, but a known method such as blowing hot air using a dryer or the like and irradiating infrared rays can be used.

The drying temperature depends on the heat resistance of the plastic film, but is preferably room temperature to 150 ° C., more preferably 50 to 120 ° C., and particularly preferably 60 to 90 ° C. When the drying temperature is room temperature or higher, the time required for drying can be shortened. When the drying temperature is 150 ° C. or lower, it is possible to suppress the generation of bubbles in the coating layer or the casting layer and the thermal deformation of the plastic film.

The drying time is not particularly limited, but is preferably 1 second to 30 minutes, more preferably 3 seconds to 15 minutes, and particularly preferably 5 seconds to 5 minutes. If the drying time is 1 second or more, the solvent can be sufficiently distilled off. If the drying time is within 30 minutes, the manufacturing cost can be within an appropriate range.

The thickness of the oxygen barrier layer is not particularly limited, but is preferably 0.1 to 50 μm, more preferably 0.2 to 30 μm, and particularly preferably 0.5 to 10 μm. When the thickness of the oxygen barrier layer is 0.1 μm or more, it is possible to suppress the occurrence of pinholes or cracks in the oxygen barrier layer and prevent the deterioration of the oxygen barrier property. When the thickness of the oxygen barrier layer is 50 μm or less, the flexibility of the oxygen barrier laminated body can be maintained.

Examples of the plastic film include polyester films such as polyethylene terephthalate (PET) film, polybutylene terephthalate (PBT) film, and polynaphthalene terephthalate (PEN) film, polystyrene film, polycarbonate (PC) film, polyamide film, polyimide film, and poly. Arilate film, polyacrylonitrile film, polyethylene film (LLDPE: linear low density polyethylene film, and HDPE: high density polyethylene film included), polypropylene film (CPP: unstretched polypropylene film, and OPP: biaxially stretched polypropylene film) Included) such as polyolefin films, polycycloolefin films, polyvinylidene chloride (PVDC) films, polyvinyl chloride (PVC) films, and clear vapor deposition films thereof. The plastic film may be subjected to surface treatment such as corona treatment.

The plastic film is preferably a polyethylene film, a polypropylene film, or a polyethylene terephthalate film, and is particularly preferably a polypropylene film, from the viewpoint of improving the oxygen barrier property of the laminate and making it easily available. By using these plastic films, it is possible to inexpensively produce a laminate having excellent water vapor barrier property and oxygen barrier property.

The oxygen permeability of the oxygen barrier laminate is preferably 300 cc / (m ² · day · atm) or less under low humidity conditions (0% RH), and is 250 cc / (m ² · day · atm). It is more preferably 200 cc / (m ² · day · atm) or less, and particularly preferably 200 cc / (m 2 · day · atm) or less. If the oxygen permeability under low humidity conditions (0% RH) is 300 cc / ( ^m2 , day, atm) or less, the oxygen deterioration of the contents when the oxygen barrier laminate is used as a packaging bag. Can be expected to have the effect of delaying.

The oxygen permeability of the oxygen barrier laminate is preferably in a range in which the barrier property does not decrease under high humidity conditions (90% RH) as compared with the conditions under low humidity conditions. Specifically, the following equation:
Oxygen permeability ratio = Oxygen permeability ratio expressed by oxygen permeability at high humidity (90% RH) / oxygen permeability at low humidity (0% RH) is preferably 5 or less. It is more preferably 4 or less, and particularly preferably 3 or less.

The oxygen barrier laminate of one embodiment may be stretched at least uniaxially. The stretching method is not particularly limited, and a known method can be used. For example, oxygen that has been simultaneously biaxially stretched by simultaneously biaxially stretching an unstretched oxygen barrier laminate in the longitudinal direction (MD) and the lateral direction (TD) using a tenter type simultaneous biaxial stretching machine. A barrier laminate can be obtained.

The oxygen barrier laminate of one embodiment may be irradiated with high energy rays such as ultraviolet rays, X-rays, and electron beams, if necessary. In this case, a component that is crosslinked or polymerized by high energy irradiation may be blended in the layer constituting the oxygen barrier laminate as long as the gas barrier property or flexibility is not impaired.

If necessary, the oxygen barrier laminate of one embodiment may be subjected to surface treatment such as corona treatment.

Various laminated films can be obtained by laminating the sealant resin on the oxygen barrier laminated body of one embodiment.

Examples of the sealant resin include low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer resin, and ethylene-acrylic acid. Examples thereof include a copolymer, an ethylene-methacrylic acid copolymer, an ethylene-acrylic acid ester copolymer, an ethylene-methacrylic acid ester copolymer, and a polyvinyl acetate-based resin. Among these, polyolefins such as polyethylene, polypropylene, and an ethylene-propylene copolymer having high heat-sealing strength or the strength of the material itself are preferable. The sealant resin may be used alone, may be copolymerized with another resin, or may be melt-mixed and used, and may be further subjected to acid modification or the like.

Examples of the method of forming the sealant layer on the oxygen barrier laminate include a method of laminating a film or sheet containing a sealant resin on the oxygen barrier laminate via an adhesive, and a method of laminating the sealant resin on the oxygen barrier laminate. Examples thereof include a method of extruding and laminating on a laminate. In the former method, the film or sheet containing the sealant resin may be in an unstretched state or in a stretched state at a low magnification. The film or sheet containing the sealant resin is preferably in an unstretched state for practical use.

The thickness of the sealant layer is not particularly limited, but is preferably 20 to 100 μm, more preferably 40 to 70 μm.

A packaging bag can be made using the oxygen barrier laminate of one embodiment. Packaging bags include, for example, fruits, juices, drinking water, liquor, cooked foods, marine products, frozen foods, meat products, boiled foods, rice cakes, liquid soups, food and drink such as seasonings, liquid detergents, cosmetics, and chemical products. It can be suitably used for filling and packaging containing the above.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following examples.

(1) Molecular weight of copolymer PLgel 5 μm Size exclusion chromatography using GPC-120 “PolymerLabs” (manufactured by Azilent Technology Co., Ltd.) equipped with a MIXED B column (two in series) (solvent: 0.1% by mass) The molecular weight of the copolymer was analyzed by using LiBr-DMF, temperature: 50 ° C., flow velocity: 1.0 mL / min) and polystyrene as a standard material for the molecular weight.

(2) Polymer copolymerization ratio The content of each of the monomer structural units represented by the formulas (1), (2) and (3) is the nuclear magnetic resonance apparatus VARIAN XR-400 or JEOL Ltd. It was determined by ¹ H-NMR analysis at room temperature using a nuclear magnetic resonance apparatus JNM-ECS400.

(3) Solubility of the copolymer A method of adding a predetermined solvent to the copolymer so that the solid content concentration becomes 5% by mass, and (A) allowing the polymer to stand at room temperature (20 to 30 ° C.) for 24 hours. Or (B) after any of the methods of heating at 40 to 70 ° C. for 5 hours and then cooling to room temperature (20 to 30 ° C.), if no insoluble matter or gel-like swollen component remains by visual observation, " It was judged as "good", and when an insoluble component or a gel-like swollen component remained, it was judged as "poor".

(4) Oxygen barrier property Oxygen permeability was measured at 20 ° C. and relative humidity of 0% RH and 90% RH according to JIS K 7126-2: 2006 (Annex A).

(5) Raw materials Allyl acetate (manufactured by Showa Denko KK) and allyl alcohol (manufactured by Aldrich) were used by distilling commercially available products. Divinylbenzene (manufactured by Aldrich) used was purified through an alumina column. As 2,2'-azobisisobutyronitrile (manufactured by Aldrich), recrystallized from methanol was used. Di (4-t-butylcyclohexyl) peroxydicarbonate was synthesized and used in accordance with US Pat. No. 7,968753.

(Example 1)
Replace the 100 mL glass flask with argon gas and add divinylbenzene (0.7 mL, 4.9 mmol) and di (4-t-butylcyclohexyl) peroxydicarbonate (2 g, 5.0 mmol) to allyl acetate (45 mL, 418 mmol). ) Was added as a solution dissolved in toluene (4 mL). The obtained mixture was heated at 40 ° C. for 18 hours to carry out a polymerization reaction, cooled to room temperature, and purified by freeze-drying using benzene to obtain a copolymer 1. The conversion of allyl acetate was 9%. Copolymer 1 was dissolved in benzene, chloroform, dimethyl sulfoxide, and dimethylformamide. The weight average molecular weight (Mw) of the copolymer 1 measured by size exclusion chromatography was 26,000, and the polydispersity (Mw / Mn) was 15.8. From ¹ H-NMR measurement using deuterated chloroform as a solvent, the integral ratio of methylene protons ( _-CH2 -OC (O)-) derived from allyl acetate found around 3.5 to 4.2 ppm and 6.2 to The molar ratio of the monomer structural unit in the copolymer 1 calculated from the integral ratio of the divinylbenzene-derived proton (-C ₆ H _4- ) found near 7.7 ppm is l = 0 mol% and m = 80 mol%. , N = 20 mol%.

(Example 2)
After heating for 18 hours in the same manner as in Example 1, divinylbenzene (0.7 mL, 4.9 mmol) and di (4-t-butylcyclohexyl) peroxydicarbonate (2 g, 5.0 mmol) were added again in toluene (4 mL). Was dissolved and added, and heated at 40 ° C. for 18 hours. After that, divinylbenzene and di (4-t-butylcyclohexyl) peroxydicarbonate were added again in the same manner, and heating at 40 ° C. for 48 hours was repeated twice, and the polymerization reaction was carried out by heating for a total of 132 hours. , The copolymer 2 was obtained by the same procedure as in Example 1. The analysis results are shown in Table 1.

(Example 3)
Divinylbenzene (0.34 mL, 2.4 mmol) and di (4-t-butylcyclohexyl) peroxydicarbonate (0.96 g, 2.4 mmol) are mixed with allyl acetate (26 mL, 242 mmol) in a glass ampoule. The ampoule was sealed after performing freeze degassing (5 × 10 ^-3 mmHg) four times. The ampoule was heated at 40 ° C. for 46 hours, cooled to room temperature, and purified by freeze-drying using benzene to obtain a copolymer 3. The conversion of allyl acetate was 17.0%. When the analysis was carried out in the same manner as in Example 1, the copolymer 3 was dissolved in benzene, chloroform, dimethylsulfoxide, and dimethylformamide, and the weight average molecular weight (Mw) of the copolymer 3 was 10,500. The polydispersity (Mw / Mn) was 7.8, and the molar ratio of the monomer structural units in the copolymer 3 was l = 0 mol%, m = 89 mol%, and n = 11 mol%. The ¹ H-NMR spectrum of the copolymer 3 is shown in FIG. 1, and the SEC chromatogram is shown in FIG. 2, respectively.

(Example 4)
After heating for 46 hours in the same manner as in Example 3, divinylbenzene (0.34 mL, 2.4 mmol) and di (4-t-butylcyclohexyl) peroxydicarbonate (0.96 g, 2.4 mmol) were added again. After freezing and degassing, the ampoule was sealed and heated at 40 ° C. for 24 hours. This operation was repeated three more times, and after heating for a total of 118 hours to carry out a polymerization reaction, the copolymer 4 was obtained by the same procedure as in Example 1. The analysis results are shown in Table 1.

(Example 5)
Polymerization was carried out in the same manner as in Example 1 except that the monomer was changed from allyl acetate to allyl alcohol and the heating time was 18 hours to obtain a copolymer 5. The analysis results are shown in Table 1.

(Example 6)
Allyl acetate (13 mL, 120 mmol), divinylbenzene (0.17 mL, 1.2 mmol) and di (4-t-butylcyclohexyl) peroxydicarbonate (0.48 g, 1.2 mmol) are mixed in a glass ampoule. The ampoule was sealed after making a solution and performing freeze degassing (5 × 10 ^-3 mmHg) four times. After heating the ampoule at 60 ° C. for 4 hours, divinylbenzene (0.17 mL, 1.2 mmol) and di (4-t-butylcyclohexyl) peroxydicarbonate (0.048 g, 0.12 mmol) were added, and 60 again. After the polymerization reaction was carried out by heating at ° C. for 16 hours, the copolymer 6 was obtained in the same procedure as in Example 1. The analysis results are shown in Table 1.

(Example 7)
Polymerization was carried out in the same manner as in Example 6 except that the amount of di (4-t-butylcyclohexyl) peroxydicarbonate to be added was changed to 0.24 g (0.60 mmol) to obtain a copolymer 7. .. The analysis results are shown in Table 1.

(Comparative Example 1)
Polymerization was carried out in the same manner as in Example 1 except that divinylbenzene was not added, to obtain a polymer C1. The analysis results are shown in Table 1.

(Comparative Example 2)
Polymerization was carried out in the same manner as in Example 1 except that the temperature was changed to 80 ° C. and 2,2'-azobisisobutyronitrile was used as a radical polymerization initiator to obtain a copolymer C2. The analysis results are shown in Table 1.

(Comparative Example 3)
Polymerization was carried out in the same manner as in Example 1 except that the amount of divinylbenzene added was changed to 1.9 mL (12.9 mmol). The obtained copolymer C3 was insoluble in benzene, chloroform and the like, and the weight average molecular weight and the molar ratio of the monomer structural units could not be calculated.

Table 1 shows the polymerization conditions and the measured values of the obtained copolymer or polymer.

In Examples 1 to 7, it was possible to produce a copolymer having a high weight average molecular weight and high solubility in a solvent. As shown in Comparative Examples 1 and 2, when the dialkenyl monomer is not added or the radical polymerization is carried out at a high temperature, the molecular weight of the copolymer becomes low. As shown in Comparative Example 3, if the amount of the dialkenyl monomer charged is too high, the copolymer gels.

(Purification Example 1)
The copolymer obtained in Example 4 was dissolved in benzene, dropped in methanol in the obtained solution, reprecipitated, and the precipitate was collected by filtration, and the analysis was carried out in the same manner as in Example 1. The produced copolymer is dissolved in benzene, chloroform, dimethylsulfoxide, dimethylformamide, and tetrahydrofuran, and the weight average molecular weight (Mw) of the copolymer is 24,000, and the polydispersity (Mw / Mn) is high. It was 3.0, and the molar ratio of the monomer structural units was l = 0 mol%, m = 87 mol%, and n = 13 mol%.

(Example 8) Sodium methoxide The copolymer 3 (2 g) obtained in Example 3 is mixed with methanol (manufactured by Wako Pure Chemical Industries, Ltd., 30 mL) and tetrahydrofuran (manufactured by Wako Pure Chemical Industries, Ltd., 5 mL). After dissolving in a solvent and adding a 10% by mass methanol solution of sodium methoxide, the mixture was heated in an oil bath at 60 ° C. for 20 hours. The mixture was cooled to room temperature, an ion exchange resin (Dowex) was added, and the mixture was stirred and then filtered. The obtained filtrate was reprecipitated with acetone, and the obtained solid was dried to obtain a saponified product (copolymer 8). .. From ¹ H-NMR measurement using methanol-d ₄ as a solvent, the integrated ratio of methylene proton (-CH ₂ -OH) derived from allyl alcohol found in the vicinity of 3.3 to 3.8 ppm and 6.0 to 7. The molar ratio of the monomer structural unit in the copolymer 8 calculated from the integral ratio of the divinylbenzene-derived proton (-C ₆ H _4- ) found around 5 ppm is l = 85 mol%, m = 0 mol%, n. = 15 mol%. The ¹ H-NMR spectrum of the copolymer 8 is shown in FIG.

(Film formation example 1)
The copolymer 8 obtained in Example 8 was dissolved in ethanol (manufactured by Wako Pure Chemical Industries, Ltd.) so that the solid content concentration was 5% by mass, and filtered through a membrane filter having a pore size of 0.45 μm. The obtained filtrate was applied to a 60 μm corona-treated biaxially stretched polypropylene (OPP) film with a bar coater, and then heated and dried in a hot air drying oven set at 40 ° C. for 10 minutes. Then, it was further heated and dried in a hot air drying oven set at 80 ° C. for 10 minutes to obtain a laminate in which the copolymer 8 was coated on the surface of the OPP film with a thickness of 5 μm. The oxygen permeability of this laminate at a temperature of 20 ° C. is 150 cc / (m ^{2 · day · atm) at a relative humidity of 0% RH and 360 cc / (m 2 ·} day · atm) at a relative humidity of 90% RH. formula:
Oxygen permeability ratio = oxygen permeability ratio at high humidity (90% RH) / oxygen permeability at low humidity (0% RH) was 2.4.

(Comparative Example 4)
The oxygen permeability of PVA (Tg = 71.0 ° C.) coated OPP film (manufactured by Mitsui Chemicals Toshiro Co., Ltd.) with a thickness of 21 μm (barrier layer thickness 1 μm) is 0.1 cc / (m ² / day / atm) at 0% RH. ), At 90% RH, it was 600 cc / (m ² / day / atm), and the ratio of oxygen permeability at high humidity to low humidity was 6000.

Claims (18)

Equation (1), Equation (2), and Equation (3)

(In the formula, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X may contain an oxygen atom and may contain an oxygen atom. It represents a divalent organic group of 1 to 20, and l, m, and n are numerical values representing the molar ratio of each monomer structural unit, and either l or m may be 0).
A copolymer having a monomer structural unit represented by (1) and satisfying the following requirements (A), (B), and (C).
(A) The molar ratio l of the monomer structural unit represented by the formula (1), the molar ratio m of the monomer structural unit represented by the formula (2), and the molar ratio n of the dialkenyl monomer structural unit represented by the formula (3). However, the following formula:
The relationship of 0.1 ≦ [n / (l + m + n)] × 100 ≦ 65 is satisfied.
(B) The weight average molecular weight Mw is 10,000 to 1,000,000.
(C) It is not gelled and dissolves in a predetermined solvent. The copolymer according to claim 1, which satisfies the relationship of 0.1 ≦ [n / (l + m + n)] × 100 ≦ 20. The copolymer according to claim 1 or 2, wherein X is −C ₆ H ₄ −. The copolymer according to any one of claims 1 to 3, wherein R ¹ , R ² and R ⁴ are hydrogen atoms. The copolymer according to any one of claims 1 to 4, wherein R ³ is a methyl group. The copolymer according to any one of claims 1 to 5, wherein either l or m is 0. The predetermined solvent is benzene, toluene, xylene, chloroform, methylene chloride, carbon tetrachloride, dichloroethane, tetrachloroethane, chlorobenzene, dichlorobenzene, trichlorobenzene, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide. , Tetrahydrofuran, methanol, ethanol, isopropanol, n-propanol, 2-butanol, n-butanol, ethyl cellosolve, and butyl cellosolve, which is at least one selected from the group according to any one of claims 1 to 6. Polymer. Equation (4)

(In the formula, R ² and R ³ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.)
2-alkenyl ester compound represented by, and formula (5)

(In the formula, R ⁴ independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X is a divalent organic group having 1 to 20 carbon atoms which may contain an oxygen atom. Represents.)
Formulations (2) and (3), which include copolymerizing the dialkenyl compound represented by (1) in the presence of a radical polymerization initiator.

(In the formula, R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X may contain an oxygen atom and have 1 to 1 carbon atoms. It represents 20 divalent organic groups, and m and n are numerical values representing the molar ratio of each monomer structural unit.)
A method for producing a copolymer having a monomer structural unit represented by. Equation (4)

(In the formula, R ² and R ³ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.)
2-alkenyl ester compound represented by, and formula (5)

(In the formula, R ⁴ independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X is a divalent organic group having 1 to 20 carbon atoms which may contain an oxygen atom. Represents.)
The dialkenyl compound represented by the above formulas (1), (2) and (3), which comprises copolymerizing in the presence of a radical polymerization initiator and then saponifying in an alcohol solvent in the presence of a catalyst.

(In the formula, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, where R ¹ and R ² are the same, and X is oxygen. It represents a divalent organic group having 1 to 20 carbon atoms which may contain an atom, l, m, and n are numerical values representing the molar ratio of each monomer structural unit, and m is 0. May be good.)
A method for producing a copolymer having a monomer structural unit represented by. Equation (6)

(In the formula, R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.)
2-Alkenyl alcohol compound represented by, and formula (5)

(In the formula, R ⁴ independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X is a divalent organic group having 1 to 20 carbon atoms which may contain an oxygen atom. Represents.)
Formulations (1) and (3), which include copolymerizing the dialkenyl compound represented by (1) in the presence of a radical polymerization initiator.

(In the formula, R ¹ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and X may contain an oxygen atom and are divalent with 1 to 20 carbon atoms. L and n are numerical values representing the molar ratio of each monomer structural unit.)
A method for producing a copolymer having a monomer structural unit represented by. The method for producing a copolymer according to claim 9, wherein m is 0. The method for producing a copolymer according to any one of claims 8 to 11, wherein R ¹ , R ² and R ⁴ are hydrogen atoms. The method for producing a copolymer according to any one of claims 8 to 12, wherein R ³ is a methyl group. The method for producing a copolymer according to any one of claims 8 to 13, wherein the radical polymerization initiator has a 10-hour half-life temperature of 50 ° C. or lower. The method for producing a copolymer according to any one of claims 8 to 14, wherein the polymerization temperature is in the range of 20 to 70 ° C. When the total molar amount of the 2-alkenyl ester compound represented by the formula (4) and the 2-alkenyl alcohol compound represented by the formula (6) is x, and the molar amount of the dialkenyl compound represented by the formula (5) is y. , The following formula:
0.1 ≦ [y / (x + y)] × 100 ≦ 65
The method for producing a copolymer according to any one of claims 8 to 15, wherein radical polymerization is carried out in the range of. An oxygen barrier laminated body comprising at least one layer of a plastic film and at least one oxygen barrier layer containing the copolymer according to any one of claims 1 to 7. The oxygen barrier laminate according to claim 17, wherein the plastic film is a polypropylene film.

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