JP5889671B2 - Ethylene vinyl acetate copolymer resin composition - Google Patents

Description

  The present invention relates to a resin composition in which an inorganic layered compound is dispersed in an ethylene vinyl acetate copolymer.

An ethylene vinyl acetate copolymer is excellent in transparency, flexibility, adhesiveness, low temperature characteristics, and insulating properties, and thus is used in a wide range of fields such as films, injection molded articles, adhesives, and electronic materials.
However, the ethylene vinyl acetate copolymer has a problem that, as the vinyl acetate content increases, the transparency, flexibility and adhesiveness are improved, while the water vapor barrier property and heat resistance are lowered.

  For this reason, in recent years, a method has been proposed in which a clay mineral, which is a kind of layered compound, is used as a filler, and a water vapor barrier property and heat resistance are improved by a composition containing an ethylene vinyl acetate copolymer and a layered compound.

  Patent Documents 1 and 2 propose a resin composition in which a swellable mica whose interlayer is modified with a specific ammonium cation is added to an ethylene-vinyl acetate copolymer.

Japanese Patent Laid-Open No. 2005-113076 JP 2011-1111564 A

  However, although the method described in Patent Document 1 has a certain effect of improving the water vapor barrier property and heat resistance, it is not yet sufficient, and has a problem that the insulating property is lowered. Although the method described in Patent Document 2 has a certain effect of improving the water vapor barrier property, the effect of improving the heat resistance is not sufficient.

  This invention is made | formed in view of the above situations, Comprising: It aims at providing the ethylene vinyl acetate copolymer resin composition which improved water vapor | steam barrier property and heat resistance.

  As a result of intensive studies to solve these problems, the present inventors refer to a swelling mica whose interlayer is modified with an ethylene vinyl acetate copolymer and a specific ammonium cation (hereinafter referred to as “organized swelling mica”). The resin composition consisting of the above) has been found to reduce the water vapor transmission rate (that is, improve the water vapor barrier property) and improve the heat resistance without greatly reducing the insulating properties, thereby completing the present invention. It was.

（Ｒは炭素数１〜３０の炭化水素基を示す。）
［２］ 膨潤性雲母が合成フッ素雲母であることを特徴とする［１］に記載のエチレン酢酸ビニル共重合体樹脂組成物。
［３］ エチレン酢酸ビニル共重合体の酢酸ビニル含有量が５〜５０重量％であることを特徴とする［１］に記載のエチレン酢酸ビニル共重合体樹脂組成物。
［４］ ［１］から［３］のいずれかに記載のエチレン酢酸ビニル共重合体樹脂組成物を含んでなることを特徴とする成形加工品。 That is, the present invention
[1] An ethylene vinyl acetate copolymer resin composition comprising an ethylene vinyl acetate copolymer and an organically swellable mica modified with an ammonium cation, wherein the ammonium cation is represented by the general formula (1).

(R represents a hydrocarbon group having 1 to 30 carbon atoms.)
[2] The ethylene-vinyl acetate copolymer resin composition according to [1], wherein the swellable mica is synthetic fluorine mica.
[3] The ethylene vinyl acetate copolymer resin composition according to [1], wherein the vinyl acetate content of the ethylene vinyl acetate copolymer is 5 to 50% by weight.
[4] A molded product comprising the ethylene vinyl acetate copolymer resin composition according to any one of [1] to [3].

  According to the present invention, an ethylene vinyl acetate resin copolymer composition excellent in water vapor barrier properties and heat resistance can be provided.

The present invention will be specifically described below.
The ethylene vinyl acetate copolymer used in the present invention is not particularly limited, and known ones can be used. Among these, from the viewpoints of transparency, heat resistance and workability, the vinyl acetate content measured according to JIS K7192 is preferably 5 to 50% by weight, more preferably 10 to 45% by weight, More preferably, it is 15 to 33% by weight.
Further, the melt flow rate (MFR) measured in accordance with JIS K7210 code D of the ethylene vinyl acetate copolymer used in the present invention is preferably 0.1 to 300 g / 10 minutes, and 1 to 100 g / 10 minutes. It is further desirable that

（Ｒは炭素数１〜３０の炭化水素基を示す。） The ethylene vinyl acetate copolymer used in the present invention may be modified with an unsaturated monomer. As unsaturated monomers, mono- or dicarboxylic acids such as acrylic acid, methacrylic acid, maleic acid and itaconic acid, and unsaturated carboxylic acid derivatives which are anhydrides thereof, hydroxyethyl (meth) acrylate, (meth) Examples include (meth) acrylic acid esters such as glycyl acrylate and aminoethyl (meth) acrylate, and alkoxysilanes having a vinyl group such as vinyltrimethoxysilane and γ-acrylic acid propyltrimethoxysilane.
The organically swellable mica used in the present invention is obtained by ion exchange of a cation between layers of swellable mica with an ammonium cation, and there is no particular limitation as long as the ammonium cation is an ammonium cation represented by the general formula (1). .

(R represents a hydrocarbon group having 1 to 30 carbon atoms.)

  The swellable mica used in the present invention is preferably a synthetic fluorine mica produced by a dry synthesis method. As such a swellable mica, Somacif (product name (registered trademark), manufactured by Corp Chemical Co., Ltd., synthetic swelling fluorinated mica) is preferable. ) And the like.

The ion-exchangeable cations existing between the layers of the above swellable mica are ions such as sodium and lithium, and these ions are easily ion-exchanged with the cationic substances, so various cationic substances are introduced between the layers. can do.
The cation exchange capacity of the swellable mica used for obtaining the organically swellable mica used in the present invention is not particularly limited, but is preferably 50 to 200 mm equivalent / 100 g, and 85 to 140 mm equivalent. More preferably.
The hydrocarbon group R of the ammonium cation represented by the formula (1) is not particularly limited as long as it is a monovalent hydrocarbon group having 1 to 30 carbon atoms, and may be linear or branched, and saturated hydrocarbon. However, it may be an unsaturated hydrocarbon.

  Examples of the hydrocarbon group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, dodecyl group, undecyl group, tridecyl group, Examples thereof include aliphatic hydrocarbon groups such as a tetradecyl group, a pentadecyl group, a hexadecyl group, an octadecyl group, a lauryl group, a stearyl group, and a behenyl group.

The content of the organically swellable mica in the ethylene vinyl acetate copolymer resin composition is preferably 1% by weight to 30% by weight, and more preferably 5% by weight to 20% by weight.
The ethylene vinyl acetate copolymer of the present invention may contain a polymer and an additive as long as the effects of the present invention are not impaired.

  There is no restriction | limiting in particular as a polymer, For example, polyethylene, a polypropylene, an ethylene-type copolymer, a polypropylene-type copolymer etc. can be mentioned. More specifically, examples of polyethylene include high density polyethylene, medium density polyethylene, low density polyethylene, linear low density polyethylene, and ultra low density polyethylene. Examples of the ethylene-based copolymer include an ethylene α-olefin copolymer, an ethylene vinyl ester copolymer, an ethylene acrylic acid copolymer, an ethylene methacrylic acid copolymer, an ethylene acrylic acid ester copolymer, and an ethylene methacrylate ester copolymer. Specific examples include ethylene 1-butene copolymer, ethylene 1-hexene copolymer, ethylene 1-octene copolymer, ethylene vinyl alcohol resin, ethylene propylene copolymer, ethylene vinyl acetate. Examples thereof include saponified copolymers, ethylene ethyl acrylate copolymers, ethylene ethyl methacrylate copolymers, and the like. Examples of the polypropylene-based copolymer include a polypropylene block copolymer and a polypropylene random copolymer.

  Examples of additives include stabilizers, lubricants, colorants (pigments and dyes, etc.), silicon oil, other oils, inorganic fillers and fillers (calcium carbonate, talc, magnesium hydroxide, silica, barium sulfate, glass filler, etc.) ), Crystal nucleating agents, ultraviolet absorbers and the like.

  The method for obtaining the ethylene vinyl acetate copolymer resin composition of the present invention is not particularly limited, and a known method can be used. For example, a melt kneading method using a general kneader such as a Banbury mixer, a kneader, a roll, a single screw extruder, a twin screw extruder, a multi-screw extruder, or after each component is dissolved or dispersed and mixed A method such as solution mixing for removing the solvent by heating is used. In particular, the melt kneading method is preferable from the viewpoints of productivity and good kneading properties.

  The present invention will be described based on examples. The present invention is not limited to these examples. The physical properties in Examples and Comparative Examples were evaluated by the following methods.

[Ethylene vinyl acetate copolymer]
Suntec EVA EM7830 (product name, manufactured by Asahi Kasei Chemicals Corporation, vinyl acetate content 28 wt%, MFR = 30.0 g / 10 min) was used.

[Swelling mica]
Somasif ME-100 (product name, manufactured by Coop Chemical Co., Ltd.)

[Evaluation method]
(1) Measurement of vinyl acetate content The vinyl acetate content was measured according to JIS K7192: 1999.
(2) Melt Mass Flow Rate (MFR) Measurement Measured according to JIS K7210 code D: 1999.
(3) Water vapor transmission rate Water vapor transmission rate was measured according to JIS K7129 C: 2008 (measurement area 9 cm ² , thickness 0.2 mm, measurement temperature 40 ° C., relative humidity 90% RH), and water vapor barrier properties were evaluated.
(4) Heat resistance An elastic modulus of a test piece having a length of 20 mm, a width of 4 mm, and a thickness of 1 mm is measured in a range of −100 to 120 ° C. using a viscoelasticity measuring device (EXSTAR6000, Seiko Instruments Inc.), The temperature when the elastic modulus reached 10 MPa was defined as the softening temperature, and the heat resistance was evaluated.
(5) Insulation 100 mm × 100 mm × 0.5 mm thickness sheet is prepared, and a digital ultrahigh resistance / microammeter (8340A, manufactured by ADC Corporation) and an electrode (12704A, manufactured by ADC Corporation) Using this, surface resistance and volume resistance were measured to evaluate insulation (applied voltage: 500 V).

[Reference Example 1] Synthesis of Organized Swelling Mica 1 15 g of swelling mica (Somasif ME-100, manufactured by Corp Chemical Co., Ltd.) was dispersed in 500 ml of water. To this was added an aqueous solution prepared by dissolving 9.2 g of trimethylstearyl ammonium chloride (Arcade 18-63, manufactured by Lion Corporation) in 150 ml of water, and the mixture was stirred at room temperature for 2 hours. The product was subjected to solid-liquid separation and washing to remove by-product salts, and then dried and pulverized to synthesize organically swellable mica 1.
Reference Example 2 Synthesis of Organized Swelling Mica 2 Reference Example 1 except that 8.4 g of trimethylbehenylammonium chloride (Arcade 22-80, manufactured by Lion Corporation) was used instead of 9.2 g of trimethylstearylammonium chloride. Similarly, organically swellable mica 2 was synthesized.
[Reference Example 3] Synthesis of Organized Swellable Mica 3 Reference Example 1 except that 10.2 g of dimethyl ditallow ammonium chloride (Arcade 2HT Flakes, manufactured by Lion Corporation) was used instead of 9.2 g of trimethylstearyl ammonium chloride. Similarly, organically swellable mica 3 was synthesized.
[Reference Example 4] Synthesis of Organized Swelling Mica 4 Instead of 9.2 g of trimethylstearyl ammonium chloride, 7.2 g of methyl oleyl bis (2-hydroxyethyl) ammonium chloride (Esocard C / 12, manufactured by Lion Corporation) was used. Except that, the organically swellable mica 4 was synthesized in the same manner as in Reference Example 1.

[Example 1]
In a lab plast mill mixer (manufactured by Toyo Seiki Co., Ltd.), 95 parts by weight of ethylene vinyl acetate copolymer and 5 parts by weight of organically swellable mica 1 are fed, melt kneaded at a set temperature of 85 ° C., and press-molded. A sheet was prepared according to the above and various evaluations were performed.
[Example 2]
A sheet of the ethylene vinyl acetate copolymer resin composition was prepared in the same manner as in Example 1 except that the organically swellable mica 2 was used instead of the organically swellable mica 1, and various evaluations were performed.

表１より、本発明により絶縁性を大きく低下させることなく、水蒸気バリア性、耐熱性に優れた樹脂組成物が得られる。 [Comparative Examples 1-4]
The same as Example 1 except that the ethylene vinyl acetate copolymer shown in Table 1, the ethylene vinyl acetate copolymer and organically swellable mica 3 or 4 or the ethylene vinyl acetate copolymer and swellable mica were used. A sheet of the ethylene vinyl acetate copolymer resin composition was prepared and various evaluations were performed.

From Table 1, the resin composition excellent in water vapor | steam barrier property and heat resistance is obtained by this invention, without significantly reducing insulation.

  Since the ethylene vinyl acetate copolymer resin composition of the present invention exhibits the above-described effects, food packaging film, pharmaceutical packaging film, electronic material film, water-stop sheet, glass interlayer film, solar cell sealing material, It can be used for hot melt adhesives, injection molded articles, foams and the like.

Claims (4)

An ethylene vinyl acetate copolymer comprising an ethylene vinyl acetate copolymer and an organically swellable mica modified with an ammonium cation, wherein the ammonium cation is represented by the general formula (1) (excluding choline and acetylcholine). Polymer resin composition.

(R represents a hydrocarbon group having 1 to 30 carbon atoms.)   2. The ethylene-vinyl acetate copolymer resin composition according to claim 1, wherein the swellable mica is synthetic fluorine mica.   2. The ethylene vinyl acetate copolymer resin composition according to claim 1, wherein the vinyl acetate content of the ethylene vinyl acetate copolymer is 5 to 50% by weight.   A molded product comprising the ethylene-vinyl acetate copolymer resin composition according to any one of claims 1 to 3.