JP2005179456A - Thermoplastic elastomer and thermoplastic elastomer composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer which has high levels of oil resistance and recyclability and is excellent in mechanical properties, and a thermoplastic elastomer composition containing the same. <P>SOLUTION: The thermoplastic elastomer has a copolymer containing acrylonitrile as a monomer and a side chain containing 0.1-50 mol% carbonyl-containing group and a nitrogen-containing hetero ring against 100 mol% monomer composing the copolymer. The thermoplastic elastomer composition contains the thermoplastic elastomer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a thermoplastic elastomer and a thermoplastic elastomer composition, and more specifically, has excellent oil resistance and can repeatedly reproduce cross-linking and dissociation due to temperature change (hereinafter sometimes simply referred to as “recyclability”). And a thermoplastic elastomer composition containing the same.

In recent years, reuse of used materials is desired from the standpoints of environmental protection and resource saving. Vulcanized rubber has a stable three-dimensional network structure in which a polymer substance and a vulcanizing agent are covalently bonded, and exhibits very high strength. However, re-molding is difficult due to strong covalent bonding. On the other hand, a thermoplastic elastomer utilizes physical cross-linking and can be easily molded by heating and melting without requiring a complicated vulcanization / molding process including pre-molding.
A typical example of such a thermoplastic elastomer includes a resin component and a rubber component. At room temperature, the microcrystalline resin component serves as a hard segment serving as a crosslinking point of a three-dimensional network structure, and the rubber component (soft segment) A thermoplastic elastomer is known that prevents plastic deformation and plastically deforms by softening or melting of a resin component when the temperature rises. However, since such a thermoplastic elastomer contains a resin component, the rubber elasticity tends to be lowered. Therefore, a material that can impart thermoplasticity without containing a resin component is required.

  In response to this problem, the present inventors have previously described that a hydrogen-bonding thermoplastic elastomer composed of an elastomeric polymer having a carbonyl group-containing group and a heterocyclic amine-containing group in the side chain has a temperature utilizing hydrogen bonding. It has been proposed that crosslink formation and crosslink dissociation can be repeated by change (see Patent Document 1).

  The thermoplastic elastomer having such characteristics has high industrial utility value and environmental protection value, and further has high cross-linking strength, and there is no change in physical properties even after repeated cross-linking and cross-linking. It is expected as a material with excellent recyclability.

  On the other hand, in the automobile industry, the electric industry, etc., rubber compositions, elastomer compositions and the like are used for various parts. Parts that require oil resistance are no exception. However, many rubber compositions and elastomer compositions having oil resistance used for these parts and the like do not have thermoplasticity, and the above-described requirement for reuse of used materials cannot be sufficiently satisfied. For example, as such a rubber composition, an α, β-ethylenically unsaturated nitrile-conjugated diene copolymer rubber (A) having a number average molecular weight of 50,000 to 150,000 is 50 to 79% by mass, and a number average molecular weight is 1. 1 to 30 mass% of α, β-ethylenically unsaturated nitrile-conjugated diene copolymer rubber (B) and 14 to 49 mass% of ethylene-α-olefin copolymer rubber (C). Examples thereof include a rubber composition (see Patent Document 2).

JP 2000-169527 A JP 2003-128842 A

  An object of the present invention is to provide a thermoplastic elastomer that can achieve both oil resistance and recyclability at a high level, and that is excellent in mechanical properties, and a thermoplastic elastomer composition containing the thermoplastic elastomer.

As a result of intensive studies to solve such problems, the present inventors have added a side chain containing a carbonyl-containing group and a nitrogen-containing heterocyclic ring to a copolymer containing acrylonitrile as a monomer constituting the main chain. It has been found that a thermoplastic elastomer having a specific ratio can achieve both oil resistance and recyclability at a high level.
That is, this invention is made | formed based on the said knowledge, and provides the following (I)-(X).

(I) A copolymer containing acrylonitrile as a monomer is added in a proportion of 0.1 to 50 mol% with respect to 100 mol% of the monomer constituting the copolymer, and a carbonyl-containing group and a nitrogen-containing complex. A thermoplastic elastomer having a side chain containing a ring (hereinafter referred to as “the thermoplastic elastomer of the present invention”).
Here, the said copolymer should just contain acrylonitrile as a monomer, Preferably let acrylonitrile be one of the monomers which comprise this copolymer in the ratio of 15-50 mass%. The copolymer may be hydrogenated.

(II) The thermoplastic elastomer according to (I), wherein the copolymer is an acrylonitrile-butadiene copolymer or a hydrogenated acrylonitrile-butadiene copolymer.

（式中、Ａは含窒素複素環であり、Ｂは単結合；酸素原子、アミノ基ＮＲ’（Ｒ’は水素原子または炭素数１〜１０のアルキル基である。）またはイオウ原子；あるいはこれらの原子または基を含んでもよい有機基である。） (III) The thermoplastic elastomer according to (I) or (II), wherein the side chain contains a structure represented by the following formula (1).

Wherein A is a nitrogen-containing heterocyclic ring, B is a single bond; an oxygen atom, an amino group NR ′ (R ′ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms) or a sulfur atom; or these An organic group that may contain any atom or group of

（式中、Ａは含窒素複素環であり、ＢおよびＤはそれぞれ独立に単結合；酸素原子、アミノ基ＮＲ’（Ｒ’は水素原子または炭素数１〜１０のアルキル基である。）またはイオウ原子；あるいはこれらの原子または基を含んでもよい有機基である。） (IV) Any of the above (I) to (III) containing a structure represented by the following formula (2) or (3), wherein the side chain is bonded to the copolymer at the α-position or β-position The thermoplastic elastomer described in 1.

(Wherein A is a nitrogen-containing heterocyclic ring, B and D are each independently a single bond; an oxygen atom, an amino group NR ′ (R ′ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms)) or A sulfur atom; or an organic group that may contain these atoms or groups.)

(V) The thermoplastic elastomer according to any one of (I) to (IV), wherein the nitrogen-containing heterocycle is a 5- or 6-membered ring.

(VI) The thermoplastic elastomer according to (V), wherein the nitrogen-containing heterocycle is a triazole ring, a thiadiazole ring, a pyridine ring, an imidazole ring or a hydantoin ring.

(VII) A thermoplastic elastomer composition containing the thermoplastic elastomer described in the above (I) to (VI) (hereinafter referred to as “the composition of the present invention”).

(VIII) The thermoplastic elastomer composition according to (VII), further containing 1 to 200 parts by mass of carbon black and / or silica with respect to 100 parts by mass of the thermoplastic elastomer.

(IX) The thermoplastic elastomer or thermoplastic elastomer composition according to any one of (I) to (VIII), which is used for oil-resistant parts.

(X) Any of the above (I) to (VI), wherein a copolymer having a cyclic acid anhydride group in the side chain and containing acrylonitrile as a monomer is reacted with a compound capable of introducing a nitrogen-containing heterocyclic ring A method for producing the thermoplastic elastomer according to claim 1.

  INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a thermoplastic elastomer that can achieve both oil resistance and recyclability at a high level and that is excellent in mechanical properties, and a thermoplastic elastomer composition containing the thermoplastic elastomer.

  In particular, the thermoplastic elastomer of the present invention retains mechanical properties comparable to those of a vulcanized acrylonitrile-butadiene rubber composition, further improves oil resistance, and the acrylonitrile-butadiene rubber composition. Because of its excellent recyclability, it can sufficiently satisfy the above requirements, and its industrial utility value and environmental protection value are extremely high. The composition of the present invention containing the thermoplastic elastomer of the present invention also exhibits the same effect and has an extremely high value.

The present invention is described in detail below.
The thermoplastic elastomer of the present invention is a copolymer containing acrylonitrile as a monomer in a proportion of 0.1 to 50 mol% with respect to 100 mol% of the monomer constituting the copolymer. It is a thermoplastic elastomer having a side chain containing a group and a nitrogen-containing heterocycle.

The reason why the thermoplastic elastomer of the present invention can achieve both oil resistance and recyclability at a high level and is excellent in mechanical properties is not clear in detail, but the inventors consider as follows. Yes.
That is, the acrylonitrile contained in the copolymer, preferably at a specific ratio, can improve the oil resistance to some extent, but cannot impart recyclability. However, oil resistance can be improved to a higher level by including a carbonyl-containing group and a nitrogen-containing heterocyclic ring in the side chain and increasing the crosslinking density at the time of crosslinking to a specific range, etc. It can impart even excellent recyclability without significant loss.

The copolymer which is the main chain of the thermoplastic elastomer of the present invention contains acrylonitrile as one of the monomers constituting the copolymer. The thermoplastic elastomer of the present invention containing acrylonitrile as a monomer can improve the oil resistance of the vulcanized acrylonitrile-butadiene rubber composition and can realize a higher level of oil resistance.
Although content of acrylonitrile is not specifically limited, It is preferable that it is 15-50 mass% with respect to the monomer which comprises this copolymer by the point which can implement | achieve a higher level of oil resistance. More preferably, it is mass%, and it is especially preferable that it is 22-50 mass%.

  The acrylonitrile content may be determined from the mass of acrylonitrile with respect to the mass of all monomers when the copolymer is produced, or the amount of bound nitrile in the copolymer may be calculated. The amount of bound nitrile is a parameter generally used for various copolymers and the like, and when a commercially available copolymer is used, it can be easily known by its grade, or acrylonitrile described in JIS K6384-1995. -It can also obtain | require based on the measuring method about a butadiene-type rubber.

The copolymer which is the main chain of the thermoplastic elastomer of the present invention is not particularly limited as long as it is a copolymer having acrylonitrile as at least one monomer, preferably in the above-described ratio.
In the present invention, “acrylonitrile” is not limited to acrylonitrile as long as it is an unsaturated nitrile, and includes acrylonitrile having a substituent, for example, methacrylonitrile.
The monomer other than acrylonitrile constituting the copolymer is not particularly limited as long as it is a monomer having an ethylenically unsaturated bond. For example, ethylene, propylene, butene, butadiene, isoprene, vinylpyridine, acrylic Examples include acids, methacrylic acid and esters thereof.

Specific examples of the copolymer include acrylonitrile-butadiene rubber (NBR), acrylonitrile-isoprene rubber (NIR), acrylonitrile-butadiene-isoprene rubber (NBIR), acrylonitrile-ethylene-butadiene rubber (NBER), and acrylonitrile- Nitrile rubber such as butadiene-vinylpyridine copolymer; methyl acrylate-acrylonitrile-butadiene rubber, acrylic acid-acrylonitrile-butadiene rubber, and the like.
Among these, nitrile rubbers such as acrylonitrile-butadiene rubber (NBR), acrylonitrile-isoprene rubber (NIR), acrylonitrile-butadiene-isoprene rubber (NBIR), acrylonitrile-butadiene-ethylene rubber (NBER) are preferable, and acrylonitrile-butadiene is preferable. Rubber (NBR) is particularly preferred.

  As the copolymer, a commercially available copolymer or the like may be used, or the copolymer may be produced by copolymerizing acrylonitrile, a monomer having an ethylenically unsaturated bond, or the like by a commonly used method.

  Examples of commercially available copolymers include acrylonitrile-butadiene rubber such as Nipol1041, Nipol1312, Nipol1411, and Nipol1034 (all manufactured by Nippon Zeon Co., Ltd.); Zetpol0020, Zetpol2000, PBZ123 (all manufactured by Nippon Zeon Co., Ltd.) Hydrogenated nitrile rubber such as Nipol 1072J, Nipol DN631 (all manufactured by Nippon Zeon Co., Ltd.), etc. Carboxylated nitrile rubber (copolymerized acrylic monomer such as methacrylic acid); Nipol DN1201L, Nipol DN224 Carboxylated nitrile rubber such as those produced by Nippon Zeon Co., Ltd. (copolymerized with an ester group or a monomer having an anti-aging function); Niopl1203JNS, Nipol PB55 1NF nitrile rubber / vinyl chloride resin blends such as (all by Nippon Zeon Co., Ltd.); JSR NE, JSR (all manufactured by Nippon Zeon Co.) nitrile rubber / EPDM blend, such as and the like.

  In the present invention, as the copolymer, a copolymer obtained by hydrogenating all or part of a copolymer composed of a monomer having acrylonitrile and an ethylenically unsaturated bond can also be used. The hydrogenated copolymer is not particularly limited, but a hydrogenation rate (hydrogenation rate) of 70% or more is preferable in that it has a small number of double bonds and a high anti-aging effect. The hydrogenation rate is more preferably 80% or more, and particularly preferably 85% or more in that the effect is superior.

Here, the hydrogenation rate refers to the ratio of the amount of double bonds changed to saturated bonds by hydrogenation to the amount of double bonds in the copolymer before hydrogenation.
When the hydrogenated copolymer is produced, the hydrogenation rate is determined, for example, by adding an alcohol solution of iodine and mercury (II) or a glacial acetic acid solution of iodine chloride to a chloroform or carbon tetrachloride solution of the hydrogenated copolymer. In addition, iodine left unreacted after standing can be titrated with a sodium thiosulfate standard solution to obtain an iodine value, and a correspondence table between iodine value and hydrogenation rate can be created and calculated. Further, when a commercially available hydrogenated copolymer is used, it can be easily known by its grade.

The hydrogenated copolymer is not particularly limited as long as it is obtained by hydrogenating the above copolymer having acrylonitrile as at least one monomer, preferably in the above-described ratio.
Specific examples of the hydrogenated copolymer include acrylonitrile-butadiene rubber (NBR), acrylonitrile-isoprene rubber (NIR), acrylonitrile-butadiene-isoprene rubber (NIR), acrylonitrile-butadiene-ethylene rubber (NBER), Hydrogenated all or part of double bonds such as acrylonitrile-butadiene-vinylpyridine copolymer; all or part of double bonds such as methyl acrylate-acrylonitrile-butadiene rubber, acrylic acid-acrylonitrile-butadiene rubber And the like obtained by hydrogenation.
Among these, all or part of double bonds such as acrylonitrile-butadiene rubber (NBR), acrylonitrile-isoprene rubber (NIR), acrylonitrile-butadiene-isoprene rubber (NIR), acrylonitrile-butadiene-ethylene rubber (NBER), etc. Hydrogenated is preferable, and in particular, all or a part of double bonds of acrylonitrile-butadiene rubber (NBR) are hydrogenated.

  The hydrogenated copolymer may be a commercially available hydrogenated copolymer or the like, or may be produced by hydrogenating the above copolymer by a commonly used method.

  Examples of commercially available hydrogenated copolymers include Zetpol 2030L (bound nitrile amount 36.2%, hydrogenation rate 80%), Zetpol 3110 (bound nitrile amount 24.6%, hydrogenation rate 93%), Zetpol 3310 ( Bonded nitrile amount 23.6%, hydrogenation rate 95%), Zetpol 4110 (bonded nitrile amount 16.7%, hydrogenation rate 93%) (all manufactured by Nippon Zeon Co., Ltd.) and the like.

The method for hydrogenating the copolymer is not particularly limited, and is performed by using a normal hydrogenation method. For example, JP-B 36-3895, JP-B 42-8933, JP-B 42-25304, JP-B 45-39274, JP-A 09-157442, JP-A 09-241431, Examples include the method described in Japanese Patent No. 3069173.
Examples of the catalyst used for hydrogenation include palladium / silica and a palladium complex (Japanese Patent Laid-Open No. 3-252405). Further, JP-A Nos. 62-125858, 62-42937, 1-445402, 1-445403, 1-445404, and 1-445405 are disclosed. Rhodium or ruthenium compounds such as those described in the publications can also be used.

  In the hydrogenation reaction, the copolymer is generally maintained at a predetermined temperature in hydrogen or an inert atmosphere, a hydrogenation catalyst is added with stirring or under stirring, and hydrogen gas is then introduced to a predetermined pressure. It is carried out by applying pressure. The inert atmosphere means an atmosphere that does not react with any participant in the hydrogenation reaction such as helium, neon, or argon. Air or oxygen is not preferable because it oxidizes the catalyst and deactivates the catalyst. Nitrogen is not preferable because it acts as a catalyst poison during the hydrogenation reaction and reduces the activity of the hydrogenation reaction. In particular, the hydrogenation reactor is most preferably an atmosphere of hydrogen gas alone. The hydrogenation reaction process for obtaining the hydrogenated copolymer can be any of a batch process, a continuous process, and a combination thereof.

The copolymer and the hydrogenated copolymer may be liquid or solid. The molecular weight is not particularly limited, and can be appropriately selected according to physical properties such as intended use and required crosslinking density. Specifically, when emphasizing the fluidity when the thermoplastic elastomer and the thermoplastic elastomer composition of the present invention are heated (decrosslinked), the copolymer and the hydrogenated copolymer are in a liquid state. For example, the weight average molecular weight is preferably 1,000 to 100,000, and particularly preferably 1,000 to 50,000. On the other hand, when emphasizing the strength of the thermoplastic elastomer and thermoplastic elastomer composition of the present invention, the copolymer and the hydrogenated copolymer are preferably solid rubber, and have a weight average molecular weight of 100, for example. 000 or more is preferable, and 500,000 to 1,500,000 is particularly preferable.
In the present invention, the weight average molecular weight is a weight average molecular weight (polystyrene conversion) measured by gel permeation chromatography (GPC). For the measurement, tetrahydrofuran (THF) is preferably used as a solvent.

The copolymer and the hydrogenated copolymer are preferably polymers having a glass transition point of room temperature (25 ° C.) or less, that is, elastomers. When the copolymer used in the present invention has two or more glass transition points or when two or more kinds of copolymers are used in combination, it is preferable that at least one of the glass transition points is 25 ° C. or lower. Within this range, the molded product exhibits rubber-like elasticity at room temperature.
In the present invention, the glass transition point is a glass transition point measured by differential scanning calorimetry (DSC-Differential Scanning Calorimetry). The temperature raising rate is preferably 10 ° C./min.

  The above copolymer and the above hydrogenated copolymer may be used singly or in combination of two or more kinds, and may be used in any combination thereof, and further required. Therefore, it may be used in combination with other rubbers as long as the object of the present invention is not impaired.

The thermoplastic elastomer of the present invention has a side chain containing a carbonyl-containing group and a nitrogen-containing heterocycle at a specific ratio in the above-described copolymer or hydrogenated copolymer.
In the present invention, “side chain” refers to a side chain and a terminal of a copolymer. “The side chain contains a carbonyl-containing group and a nitrogen-containing heterocycle” means that the carbonyl-containing group and the nitrogen-containing heterocycle are chemically stable bonds to atoms (usually carbon atoms) that form the copolymer ( Means a covalent bond).

The carbonyl-containing group is not particularly limited as long as it contains a carbonyl group, and specific examples thereof include an amide group, an ester group, an imide group, a carboxy group, and a carbonyl group. The compound into which such a group can be introduced is not particularly limited, and specific examples thereof include ketones, carboxylic acids and derivatives thereof.
Examples of the carboxylic acid include organic acids having a saturated or unsaturated hydrocarbon group, and the hydrocarbon group may be any of aliphatic, alicyclic, aromatic and the like. Specific examples of carboxylic acid derivatives include carboxylic acid anhydrides, amino acids, thiocarboxylic acids (mercapto group-containing carboxylic acids), esters, amino acids, ketones, amides, imides, dicarboxylic acids, and the like. A monoester etc. are mentioned.

Specific examples of the carboxylic acid and derivatives thereof include malonic acid, maleic acid, succinic acid, glutaric acid, phthalic acid, isophthalic acid, terephthalic acid, p-phenylenediacetic acid, p-hydroxybenzoic acid, p -Carboxylic acids such as aminobenzoic acid and mercaptoacetic acid and these carboxylic acids containing substituents; Acid anhydrides such as succinic anhydride, maleic anhydride, glutaric anhydride, phthalic anhydride, propionic anhydride, benzoic anhydride; Aliphatic esters such as maleic acid ester, malonic acid ester, succinic acid ester, glutaric acid ester, ethyl acetate; phthalic acid ester, isophthalic acid ester, terephthalic acid ester, ethyl-m-aminobenzoate, methyl-p-hydroxybenzoate, etc. Aromatic esters of quinone, anthraquinone, naphtho Ketones such as glycine, amino acids such as glycine, tyrosine, bicine, alanine, valine, leucine, serine, threonine, lysine, aspartic acid, glutamic acid, cysteine, methionine, proline, N- (p-aminobenzoyl) -β-alanine; Maleamide, maleamic acid (maleic monoamide), succinic monoamide, 5-hydroxyvaleramide, N-acetylethanolamine, N, N′-hexamethylenebis (acetamide), malonamide, cycloserine, 4-acetamidophenol, p- Amides such as acetamide benzoic acid; imides such as maleimide, succinimide, and urazole (3,5-dioxo-1,2,4-triazolidine).
Of these, the compound capable of introducing a carbonyl group (carbonyl-containing group) is preferably a cyclic acid anhydride such as succinic anhydride, maleic anhydride, glutaric anhydride or phthalic anhydride, or an imide such as urazole, Particularly preferred are maleic anhydride and urazole.

The nitrogen-containing heterocycle contained in the side chain of the thermoplastic elastomer is introduced into the copolymer directly or via an organic group.
As the nitrogen-containing heterocycle, those having a heteroatom other than a nitrogen atom in the heterocycle, for example, a sulfur atom, an oxygen atom, a phosphorus atom, etc. can be used as long as the heterocycle contains a nitrogen atom. Here, the reason why the heterocyclic compound is used is that if it has a heterocyclic structure, hydrogen bonds that form a bridge, which will be described later, become stronger and the tensile strength of the composition is improved.
The heterocyclic ring may have a substituent, for example, an alkyl group such as a methyl group, an ethyl group, a (iso) propyl group, or a hexyl group; a methoxy group, an ethoxy group, a (iso) propoxy group, or the like. An alkoxy group; a group consisting of a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom, an iodine atom; a cyano group; an amino group; an aromatic hydrocarbon group; an ester group; an ether group; an acyl group; A combination of these can also be used.
The substitution position of these substituents is not particularly limited, and the number of substituents is not limited. Further, the heterocyclic ring may or may not have aromaticity, but if it has aromaticity, the tensile strength at the time of crosslinking is further increased and the strength of the composition is further improved. This is preferable.

Such a nitrogen-containing heterocycle is preferably a 5-membered ring or a 6-membered ring.
Examples of the nitrogen-containing heterocyclic ring include pyrrololine, pyrrolidone, oxindole (2-oxindole), indoxyl (3-oxindole), dioxindole, isatin, indolyl, phthalimidine, β-isoindigo, monoporphyrin, diporphyrin, Triporphyrin, azaporphyrin, phthalocyanine, hemoglobin, uroporphyrin, chlorophyll, phyroerythrin, imidazole, pyrazole, triazole, tetrazole, benzimidazole, benzopyrazole, benzotriazole, imidazoline, imidazolone, imidazolidone, hydantoin, pyrazoline, pyrazolone, pyrazolidone, Indazole, pyridoindole, purine, cinnoline, pyrrole, pyrroline, indole, indoline, oxy Luindole, carbazole, phenothiazine, indolenine, isoindole, oxazole, thiazole, isoxazole, isothiazole, oxadiazole, thiadiazole, oxatriazole, thiatriazole, phenanthroline, oxazine, benzoxazine, phthalazine, pteridine, pyrazine, phenazine, Tetrazine, benzoxazole, benzisoxazole, anthranyl, benzothiazole, benzofurazan, pyridine, quinoline, isoquinoline, acridine, phenanthridine, anthrazolin, naphthyridine, thiazine, pyridazine, pyrimidine, quinazoline, quinoxaline, triazine, histidine, triazolidine, melamine, Adenine, guanine, thymine, cytosine, urazole etc. It is. Among such nitrogen-containing heterocycles, the following compounds are preferably exemplified particularly for nitrogen-containing 5-membered rings. These may have the above-described various substituents, and may be those in which a hydrogen atom is added or eliminated.

  Moreover, about a nitrogen-containing 6-membered ring, the following compound is illustrated preferably. These may also have the above-mentioned various substituents, and may be those in which a hydrogen atom is added or eliminated.

  Moreover, what condensed the said nitrogen-containing heterocyclic ring, a benzene ring, or nitrogen-containing heterocyclic rings can also be used, for example, the following condensed rings are illustrated preferably. These may also have the above-mentioned various substituents, and may be those in which a hydrogen atom is added or eliminated.

  Among the nitrogen-containing heterocycles described above, a triazole ring, a pyridine ring, a thiadiazole ring, an imidazole ring and a hydantoin ring are preferable because of excellent recyclability and mechanical strength of the thermoplastic elastomer.

In the thermoplastic elastomer of the present invention, the nitrogen-containing heterocycle is introduced into the copolymer directly or via an organic group, but is preferably introduced into the copolymer via an organic group.
In the thermoplastic elastomer of the present invention, the carbonyl-containing group and the nitrogen-containing heterocyclic ring may be introduced into the copolymer as mutually independent side chains, and the carbonyl-containing group and the nitrogen-containing heterocyclic ring are different from each other. It may be bonded to one side chain via a group and introduced into the copolymer.
A carbonyl-containing group and a nitrogen-containing heterocycle are preferably introduced into the copolymer directly or via an organic group as one side chain represented by the following formula (1).

（式中、Ａは含窒素複素環であり、Ｂは単結合；酸素原子、アミノ基ＮＲ’（Ｒ’は水素原子または炭素数１〜１０のアルキル基）またはイオウ原子；あるいはこれらの原子または基を含んでもよい有機基である。）

(Wherein A is a nitrogen-containing heterocyclic ring, B is a single bond; oxygen atom, amino group NR ′ (R ′ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms) or sulfur atom; or these atoms or An organic group that may contain a group.)

The nitrogen-containing heterocyclic ring A is specifically the nitrogen-containing heterocyclic ring described above.
Substituent B is a single bond; an oxygen atom, an amino group NR ′ (R ′ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms) or a sulfur atom; or an organic group that may contain these atoms or groups, Specifically, for example, a single bond; an oxygen atom, a sulfur atom, or an amino group NR ′ (R ′ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms); 20 alkylene group or aralkylene group; an alkylene ether group having 1 to 20 carbon atoms (an alkyleneoxy group, for example, —O—CH ₂ CH ₂ — group) or an alkyleneamino group (for example, having such an atom or group as a terminal) , —NH—CH ₂ CH ₂ — group or the like) or alkylene thioether group (alkylene thio group, for example, —S—CH ₂ CH ₂ — group); And an aralkylene ether group having 1 to 20 carbon atoms (aralkyleneoxy group), an aralkyleneamino group, or an aralkylenethioether group.

Here, the alkyl group having 1 to 10 carbon atoms of the amino group NR ′ includes methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, including isomers. Group, decyl group and the like.
An oxygen atom, a sulfur atom and an amino group NR ′ of the substituent B; and; an alkylene ether group, an alkylene amino group, an alkylene thioether group or an aralkylene having 1 to 20 carbon atoms terminated with these atoms or groups. Oxygen atom such as ether group, aralkyleneamino group, aralkylenethioether group, amino group NR 'and sulfur atom are combined with adjacent carbonyl group to form conjugated ester group, amide group, imide group, thioester group, etc. It is preferable to do this.
Substituent B is an oxygen atom, a sulfur atom or an amino group that forms a conjugated system, among those described above; an alkylene ether group, alkyleneamino group or alkylenethioether having 1 to 20 carbon atoms having these atoms or groups at the terminal Group is preferred, an amino group (NH), an alkyleneamino group (—NH—CH ₂ — group, —NH—CH ₂ CH ₂ — group, —NH—CH ₂ CH ₂ CH ₂ — group), an alkylene ether group (— O-CH ₂ - group, _{-O-CH 2 CH} 2 - _{group, -O-CH 2 CH 2 CH} 2 - group) is particularly preferred.

  The carbonyl-containing group and the nitrogen-containing heterocycle are more preferably introduced into the copolymer at the α-position or β-position thereof as one side chain represented by the following formula (2) or (3).

（式中、Ａは含窒素複素環であり、ＢおよびＤはそれぞれ独立に、単結合；酸素原子、アミノ基ＮＲ’（Ｒ’は水素原子または炭素数１〜１０のアルキル基）またはイオウ原子；あるいはこれらの原子または基を含んでもよい有機基である。）

(In the formula, A is a nitrogen-containing heterocyclic ring, B and D are each independently a single bond; an oxygen atom, an amino group NR ′ (R ′ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms) or a sulfur atom. Or an organic group that may contain these atoms or groups.)

Here, the nitrogen-containing heterocyclic ring A is basically the same as the nitrogen-containing heterocyclic ring A of the above formula (1), and the substituents B and D are each independently of the substituent B of the above formula (1). The same as above.
However, the substituent D in the above formula (3) is a C 1-20 which may contain a single bond; an oxygen atom, an amino group NR ′ or a sulfur atom, as exemplified by the substituent B in the above formula (1). It preferably forms a conjugated system with an imide nitrogen of an alkylene group or an aralkylene group, and a single bond is particularly preferable. That is, it is preferable to form an alkyleneamino group or an aralkyleneamino group having 1 to 20 carbon atoms which may contain an oxygen atom, an amino group NR ′ or a sulfur atom together with the imide nitrogen of the above formula (3). It is particularly preferable that the nitrogen-containing heterocycle is directly bonded to the imide nitrogen of 3) (single bond). Specifically, the substituent D is a single bond; an alkylene ether group, an alkylene amino group, an alkylene thioether group, or an aralkylene ether group having 1 to 20 carbon atoms having the above-described oxygen atom, sulfur atom, or amino group as a terminal. , Aralkylene amino group, aralkylene thioether group and the like; methylene group, ethylene group, propylene group, butylene group, hexylene group, phenylene group, xylylene group and the like including isomers.

  The ratio of the carbonyl-containing group and the nitrogen-containing heterocyclic ring contained in the thermoplastic elastomer is not particularly limited, but it is complementary if it is 2: 1 (1: 1 in the case of the imide structure of the above formula (3)). This is preferable because it is easy to form a natural interaction and can be easily manufactured.

  The side chain containing a carbonyl-containing group and a nitrogen-containing heterocyclic ring is introduced at a ratio (introduction ratio) of 0.1 to 50 mol% with respect to 100 mol% of the monomer constituting the copolymer. Is preferred. If it is less than 0.1 mol%, the strength at the time of crosslinking may not be sufficient, and if it exceeds 50 mol%, the crosslinking density may increase and rubber elasticity may be lost. That is, if it is within the above-mentioned range, the interaction between the side chains of the thermoplastic elastomer occurs between molecules or within the molecule, and since these are well-balanced, the tensile strength at the time of crosslinking is very high, Excellent recyclability and oil resistance can be improved. It is more preferable that the side chain is introduced at a ratio of 0.1 to 30 mol%, and it is more preferable that the side chain is introduced at a ratio of 0.5 to 20 mol% from the viewpoint that these characteristics are more excellent.

  When the carbonyl-containing group and the nitrogen-containing heterocycle are independently introduced, the introduction ratio may be considered as a set of both groups according to the ratio of the carbonyl-containing group and the nitrogen-containing heterocycle. When such a group is excessive, the larger group may be considered as a reference.

  The thermoplastic elastomer of the present invention preferably has a glass transition point of 25 ° C. or lower. When the thermoplastic elastomer has two or more glass transition points, or when two or more thermoplastic elastomers are used in combination, glass is used. At least one of the transition points is preferably 25 ° C. or lower. If the glass transition point is 25 ° C. or lower, the molded article exhibits rubber-like elasticity at room temperature.

The method for producing the thermoplastic elastomer of the present invention is not particularly limited, and a normal method can be selected.
Among the thermoplastic elastomers of the present invention, those having a carbonyl-containing group and a nitrogen-containing heterocyclic ring in the same side chain include, for example, a nitrogen-containing heterocyclic ring in the copolymer having a cyclic acid anhydride group in the side chain. It can be obtained by reacting a compound that can be introduced. Specifically, the copolymer having a cyclic acid anhydride group in the side chain is mixed with a compound capable of introducing a nitrogen-containing heterocyclic ring, and the cyclic acid anhydride group and the compound are chemically bonded at a temperature. It can be obtained by reacting under heating.

  Here, the compound capable of introducing a nitrogen-containing heterocycle may be a nitrogen-containing heterocycle itself, or a substituent that reacts with a cyclic acid anhydride group such as maleic anhydride (for example, a hydroxyl group, a thiol group, an amino acid). A nitrogen-containing heterocyclic ring having a group or the like). Moreover, what is necessary is just to make the compound which can introduce | transduce a nitrogen-containing heterocyclic ring react with a part or whole quantity of the cyclic acid anhydride group which the said copolymer has. The part is preferably 1 mol% or more, more preferably 50 mol% or more, and particularly preferably 80 mol% or more with respect to 100 mol% of the cyclic acid anhydride group. If it is this range, the effect which introduce | transduced the nitrogen-containing heterocyclic ring will express, and the tensile strength at the time of bridge | crosslinking will increase more. In view of excellent recyclability and tensile strength, it is particularly preferable to react the total amount (100 mol%) of the cyclic acid anhydride group with the compound.

The copolymer having a cyclic acid anhydride group in the side chain used in the above production method is prepared by a usual method, for example, cyclic acid anhydride by the usual conditions such as stirring under heating. The product may be produced by graft polymerization, or a commercially available product may be used.
Examples of commercially available products include carboxy-modified nitrile rubbers such as Clinac 110, 221 and 231 (manufactured by Policer Co.); carboxy group-containing acrylonitrile-butadiene rubbers such as Nipol 1072J and DN631 (both manufactured by Nippon Zeon Co., Ltd.), and the like. Is mentioned.

  Moreover, in this invention, after making the compound which can introduce | transduce a carbonyl containing group and a nitrogen-containing heterocyclic ring react, you may introduce | transduce into the side chain of the said copolymer, or as a side chain.

When synthesizing a thermoplastic elastomer having a carbonyl-containing group and a nitrogen-containing heterocyclic ring independently in the side chain, a monomer capable of forming the copolymer and a monomer containing a carbonyl-containing group are included. The thermoplastic elastomer may be directly produced by copolymerizing with a monomer containing a nitrogen heterocycle, and a copolymer is formed in advance by copolymerization or the like, and then the carbonyl-containing group and the nitrogen-containing heterocycle are formed. Graft modification may be performed with a compound capable of introducing.
In each of the above production methods, whether each group of the side chain of the thermoplastic elastomer is independently bonded or bonded to each other is confirmed by a commonly used analytical means such as NMR or IR spectrum. be able to.

  The thermoplastic elastomer of the present invention is a compound capable of introducing a nitrogen-containing heterocycle into the above copolymer having a cyclic acid anhydride in the side chain, and a compound capable of introducing a nitrogen-containing heterocycle. A carbonyl-containing group and a nitrogen-containing heterocycle are introduced into the copolymer by reaction at a temperature at which a cyclic acid anhydride group can chemically bond (for example, a covalent bond or an ionic bond) (the cyclic acid anhydride group is ring-opened). ).

For convenience, the nitrogen heterocycle of the present invention is referred to as “nitrogen-containing n-membered ring compound (n ≧ 3)”, and the bonding position of the nitrogen-containing heterocycle will be described.
The bonding positions described below (“1 to n position”) are based on the IUPAC nomenclature. For example, in the case of a compound having three nitrogen atoms having an unshared electron pair, the bonding position is determined by the order based on the IUPAC nomenclature. Specifically, the bonding positions are indicated on the 5-membered, 6-membered and condensed nitrogen-containing heterocycles exemplified above.
In the thermoplastic elastomer, the bonding position of the nitrogen-containing n-membered ring compound bonded to the copolymer directly or through an organic group is not particularly limited, and may be any bonding position (position 1 to position n). Preferably, it is the 1-position or 3-position to n-position.

When the nitrogen-containing n-membered ring compound contains one nitrogen atom (for example, a pyridine ring), the chelate is easily formed in the molecule, and the physical properties such as tensile strength when the composition is obtained are excellent. The (n-1) position is preferred.
By selecting the bonding position of the nitrogen-containing n-membered ring compound, the thermoplastic elastomer is easy to form crosslinks due to hydrogen bond, ionic bond, coordination bond, etc. between the molecules of the thermoplastic elastomer, and is excellent in recyclability. Excellent mechanical properties.

Next, the composition of the present invention will be described.
The composition of the present invention contains at least one thermoplastic elastomer of the present invention. The mixing ratio in the case of containing two or more kinds can be set to any ratio depending on the use of the composition, the physical properties required for the composition, and the like.

The composition of the present invention preferably contains carbon black and / or silica as a reinforcing agent. The type of the carbon black is appropriately selected according to the use. Generally, carbon black is classified into hard carbon and soft carbon based on the particle diameter. Soft carbon has low reinforcement to rubber, and hard carbon has strong reinforcement to rubber. In the present invention, it is particularly preferable to use hard carbon having strong reinforcing properties.
The content of carbon black (when used alone) is 1 to 200 parts by weight, preferably 10 to 100 parts by weight, more preferably 20 to 100 parts by weight with respect to 100 parts by weight of the thermoplastic elastomer of the present invention. 80 parts by mass.

The silica is not particularly limited, and examples thereof include fumed silica, calcined silica, precipitated silica, pulverized silica, fused silica, diatomaceous earth and the like, and the content thereof (when silica is used alone) is the thermoplastic elastomer of the present invention. It is 1-200 mass parts with respect to 100 mass parts, Preferably it is 10-100 mass parts, More preferably, it is 20-80 mass parts. Of these, precipitated silica is preferable.
When silica is used as the reinforcing agent, a silane coupling agent can be used in combination. Examples of the silane coupling agent include bis (triethoxysilylpropyl) tetrasulfide (Si69), bis (triethoxysilylpropyl) disulfide (Si75), γ-mercaptopropyltrimethoxysilane, vinyltrimethoxysilane, and the like. Moreover, the above-mentioned aminosilane compound can also be used.

  When carbon black and silica are used in combination, the content (total amount of carbon black and silica) is 1 to 200 parts by weight, preferably 10 to 100 parts by weight, based on 100 parts by weight of the thermoplastic elastomer of the present invention. Yes, more preferably 20 to 80 parts by mass.

  The composition of the present invention includes, if necessary, a polymer other than the thermoplastic elastomer used in the present invention, a reinforcing agent (filler) other than carbon black and silica, and an antioxidant, as long as the object of the present invention is not impaired. , Antioxidants, pigments (dyes), plasticizers, thixotropic agents, UV absorbers, flame retardants, solvents, surfactants (including leveling agents), dispersants, dehydrating agents, rust inhibitors, adhesion promoters Further, various additives such as an antistatic agent and a filler can be contained.

As the additive and the like, commonly used ones can be used, and specific examples thereof are shown below, but are not limited to those exemplified.
As the polymer other than the thermoplastic elastomer used in the present invention, a polymer having a glass transition temperature of 25 ° C. or lower is preferable as described above. Specifically, for example, natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), 1,2-butadiene rubber, styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), butyl rubber ( IIR), ethylene-propylene-diene rubber (EPDM), ethylene-propylene rubber (EPM), ethylene-butene rubber (EBM), etc., particularly polymers or unsaturated bonds having no unsaturated bond of IIR, EPM, EBM Polymer with low content (eg, EPDM) is preferred. A polymer having a site capable of hydrogen bonding is also preferable, and examples thereof include polyester, polylactone, and polyamide. The other polymer may contain one kind or two or more kinds. The content of the polymer is preferably 0.1 to 100 parts by mass, and more preferably 1 to 50 parts by mass with respect to 100 parts by mass of the thermoplastic elastomer of the present invention.

  As reinforcing agents other than carbon black and silica, for example, iron oxide, zinc oxide, aluminum oxide, titanium oxide, barium oxide, magnesium oxide, calcium carbonate, magnesium carbonate, zinc carbonate, wax stone clay, kaolin clay, calcined clay, etc. Is mentioned. 10-100 mass parts is preferable with respect to 100 mass parts of thermoplastic elastomers of this invention, and, as for these content, 20-80 mass parts is more preferable.

Examples of the antioxidant include hindered phenol compounds, aliphatic and aromatic hindered amine compounds, and the like.
Examples of the antioxidant include butylhydroxytoluene (BHT) and butylhydroxyanisole (BHA).
Examples of the pigment include titanium dioxide, zinc oxide, ultramarine, bengara, lithopone, lead, cadmium, iron, cobalt, aluminum, hydrochloride, sulfate, and other inorganic pigments, azo pigments, copper phthalocyanine pigments, and the like. .

Plasticizers include derivatives such as benzoic acid, phthalic acid, trimellitic acid, pyromellitic acid, adipic acid, sebacic acid, fumaric acid, maleic acid, itaconic acid, citric acid, polyester, polyether, epoxy, etc. Is mentioned.
Examples of thixotropic agents include benton, silicic anhydride, silicic acid derivatives, urea derivatives and the like.
Examples of the ultraviolet absorber include 2-hydroxybenzophenone, benzotriazole, and salicylic acid ester.
Examples of the flame retardant include phosphorus series such as TCP, halogen series such as chlorinated paraffin and perchlorpentacyclodecane, antimony series such as antimony oxide, and aluminum hydroxide.

Solvents include hydrocarbons such as hexane and toluene; halogenated hydrocarbons such as tetrachloromethane; ketones such as acetone and methyl ethyl ketone; ethers such as diethyl ether and tetrahydrofuran; esters such as ethyl acetate; It is done.
Examples of the surfactant (leveling agent) include polybutyl acrylate, polydimethylsiloxane, a modified silicone compound, and a fluorine-based surfactant.
Examples of the dehydrating agent include vinyl silane.

Examples of the rust inhibitor include zinc phosphate, tannic acid derivatives, phosphate esters, basic sulfonates, and various rust preventive pigments.
Examples of the adhesion imparting agent include known silane coupling agents, silane compounds having an alkoxysilyl group, titanium coupling agents, zirconium coupling agents and the like. More specifically, for example, trimethoxyvinylsilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane and the like can be mentioned.
Generally as an antistatic agent, hydrophilic compounds, such as a quaternary ammonium salt or polyglycol and an ethylene oxide derivative, are mentioned.

  The content of the plasticizer is preferably 0.1 to 50 parts by mass, and more preferably 1 to 30 parts by mass with respect to 100 parts by mass of the thermoplastic elastomer of the present invention. The content of other additives is preferably 0.1 to 10 parts by mass, and more preferably 1 to 5 parts by mass with respect to 100 parts by mass of the thermoplastic elastomer of the present invention.

Some of the thermoplastic elastomers of the present invention can self-crosslink, but vulcanizing agents, vulcanization aids, vulcanization accelerators, vulcanization retarders, etc. can be used in combination as long as the object of the present invention is not impaired. .
Examples of the vulcanizing agent include sulfur-based, organic peroxide-based, metal oxide-based, phenolic resin, quinone dioxime and other vulcanizing agents.
Examples of the sulfur vulcanizing agent include powdered sulfur, precipitated sulfur, highly dispersible sulfur, surface-treated sulfur, insoluble sulfur, dimorpholine disulfide, alkylphenol disulfide, and the like.
Examples of organic peroxide vulcanizing agents include benzoyl peroxide, t-butyl hydroperoxide, 2,4-dichlorobenzoyl peroxide, 2,5-dimethyl-2,5-di (t-butyl peroxide). Oxy) hexane, 2,5-dimethylhexane-2,5-di (peroxylbenzoate), and the like.
Other examples include magnesium oxide, risurge (lead oxide), p-quinonedioxime, tetrachloro-p-benzoquinone, p-dibenzoylquinonedioxime, poly-p-dinitrosobenzene, and methylenedianiline.

Vulcanization aids include zinc oxide, magnesium oxide, amines; fatty acids such as acetyl acid, propionic acid, butanoic acid, stearic acid, acrylic acid, maleic acid; zinc acetylate, zinc propionate, zinc butanoate, stearin Examples include zinc acid, zinc acrylate, and fatty acid zinc such as zinc maleate.
Vulcanization accelerators include thiurams such as tetramethylthiuram disulfide (TMTD) and tetraethylthiuram disulfide (TETD); aldehydes and ammonia such as hexamethylenetetramine; guanidines such as diphenylguanidine; 2-mercaptobenzothiazole, dibenzo Thiazoles such as thiazyl disulfide (DM); sulfenamides such as N-cyclohexyl-2-benzothiazylsulfenamide, Nt-butyl-2-benzothiazylsulfenamide; . Furthermore, alkylphenol resins and their halides can also be used.
Examples of the vulcanization retarder include organic acids such as phthalic anhydride, benzoic acid, salicylic acid, acetylsalicylic acid; N-nitrosodiphenylamine, N-nitrosophenyl-β-naphthylamine, N-nitroso-trimethyl-dihydroquinoline. Nitroso compounds such as polymers; halides such as trichloromelanin; 2-mercaptobenzimidazole; N- (cyclohexylthio) phthalimide (Santgard PVI) and the like.
The content of these vulcanizing agents is preferably 0.1 to 20 parts by mass and more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the thermoplastic elastomer.

  The method for producing the composition of the present invention is not particularly limited. For example, the thermoplastic elastomer of the present invention and various additives as necessary may be mixed by a roll, a kneader, an extruder, a universal stirrer, or the like.

  The curing conditions when the composition of the present invention is permanently crosslinked (with a vulcanizing agent) can be appropriately selected according to various components to be blended, and are not particularly limited. For example, curing conditions for curing at a temperature of 130 to 200 ° C. for 5 to 30 minutes are preferable.

  When the thermoplastic elastomer of the present invention and the composition of the present invention are heated to about 80 to 200 ° C., the three-dimensional crosslinked bond (crosslinked structure) is dissociated and softened to impart fluidity. This is considered to be because the interaction between the side chains formed between the molecules or within the molecule is weakened. When the thermoplastic elastomer of the present invention and the composition of the present invention to which the softness and fluidity are imparted are allowed to stand at about 80 ° C. or less, the dissociated three-dimensional cross-linked bond (cross-linked structure) is bonded again and cured. . By repeating this, the thermoplastic elastomer of the present invention and the composition of the present invention exhibit recyclability.

  The thermoplastic elastomer of the present invention and the composition of the present invention can be used for various rubber applications utilizing, for example, rubber elasticity. Moreover, since it can improve heat resistance and recyclability, it is preferable to use it as a hot melt adhesive or as an additive contained therein. The thermoplastic elastomer of the present invention and the composition of the present invention can be suitably used around an automobile or the like.

  Specific examples of the vehicle periphery include, for example, tire treads, carcass, sidewalls, inner liners, under treads, belt portions, and other tire parts; exterior radiator grilles, side moldings, garnishes (pillars, rears, cowls). Top), aero parts (air dam, spoiler), wheel cover, weather strip, cow belt grille, air outlet louver, air scoop, hood bulge, vent parts, anti-corrosion parts (over fender, side seal panel, molding ( Window, hood, door belt)), marks; door, light, wiper weather strip, glass run, glass run channel and other interior window frame parts; air duct hose, radiator hose, brake hose; crankshaft seat , Valve stem seal, head cover gasket, A / T oil cooler hose, mission oil seal, P / S hose, P / S oil seal and other lubricating oil parts; fuel hose, emission control hose, inlet filler hose, diaphragms Anti-vibration parts such as engine mounts and in-tank pump mounts; Boots such as CVJ boots and rack & pinion boots; Air-conditioning parts such as A / C hoses and A / C seals; Timing Belt parts such as belts and auxiliary belts; sealers such as windshield sealers, vinyl plastisol sealers, anaerobic sealers, body sealers, spot weld sealers; and the like.

  Further, when a rubber modifier, for example, a flow preventing agent, is included in a resin or rubber that causes a cold flow at room temperature, it is possible to prevent a flow during extrusion or a cold flow.

  Furthermore, the composition of the present invention comprising the thermoplastic elastomer of the present invention and carbon black and / or silica has improved tensile strength, tear strength, bending strength, and in particular, tires, hoses, belts, sheets, vibration-proof rubbers, Rollers, linings, rubberized fabrics, sealing materials, gloves, fenders, medical rubber (syringe gaskets, tubes, catheters), gaskets (for home appliances and construction), asphalt modifiers, hot melt adhesives, boots , Grips, toys, shoes, sandals, keypads, gears, PET bottle cap liners and the like.

  The thermoplastic elastomer and the thermoplastic elastomer composition of the present invention have the same mechanical properties as those of the conventional vulcanized acrylonitrile-butadiene rubber composition, and have excellent oil resistance. Among them, it is suitably used for applications requiring particularly recyclability and oil resistance.

  EXAMPLES Next, although an Example is shown and this invention is demonstrated more concretely, this invention is not limited to these.

A thermoplastic elastomer was synthesized by the following method.
(Synthesis Example 1: Thermoplastic Elastomer 1)
To a pressure kneader set at 90 ° C., hydrogenated acrylonitrile-butadiene rubber 1 (HNBR1, 36.2% bonded nitrile, hydrogenation rate (hydrogenation rate) 80%, iodine value 57 mg / 100 mg, Zetpol 2030 L, Nippon Zeon ( 120 g), and after masticating for several minutes, 3.93 g (0.0401 mol) of maleic anhydride and 1.20 g of anti-aging agent (NOCRACK 6C, manufactured by Ouchi Shinsei Chemical Co., Ltd.) Added and mixed for 5 minutes. The mixture was taken out from the pressure kneader, the temperature of the pressure kneader was set to 260 ° C., and the mixture taken out was charged again and mixed for 50 minutes. The obtained mixture was dissolved in methyl ethyl ketone and then crystallized by adding acetonitrile to obtain a modified rubber.
The obtained modified rubber was analyzed by ¹ H-NMR and IR to confirm that it was a hydrogenated acrylonitrile-butadiene rubber having maleic anhydride as a side chain, and the amount of maleic anhydride introduced was confirmed. It was 0.62 mol% with respect to 100 mol% of all monomers of hydrogenated acrylonitrile-butadiene rubber.

  120 g of this modified rubber was put into a pressure kneader adjusted to 140 ° C. and stirred for 1 minute, and 1.2 g of 3-amino-1,2,4-triazole (manufactured by Nippon Carbide Co., Ltd.) (in 120 g of modified rubber) And equimolar amount of maleic anhydride contained in the mixture, and kneaded for 50 minutes while maintaining the same temperature to obtain a thermoplastic elastomer 1 (the introduction rate of side chains in the thermoplastic elastomer 1 is 0.62 mol) %Met.).

(Synthesis Example 2: Thermoplastic Elastomer 2)
Instead of HNBR1, hydrogenated acrylonitrile-butadiene rubber 2 (bound nitrile content 23.6%, hydrogenation rate (hydrogenation rate) 95%, iodine value 15 mg / 100 mg, Zetpol 3310, manufactured by Nippon Zeon Co., Ltd.) was used. Except for the above, a thermoplastic elastomer 2 was obtained in the same manner as the thermoplastic elastomer 1 described above.
The amount of maleic anhydride introduced and the side chain introduction rate of the thermoplastic elastomer 2 were 0.60 mol%.

(Synthesis Example 3: Thermoplastic Elastomer 3)
Instead of NBR1, hydrogenated acrylonitrile-butadiene rubber 3 (bound nitrile amount 18.6%, hydrogenation rate (hydrogenation rate) 93%, iodine value 15 mg / 100 mg, Zetpol 4310, manufactured by Nippon Zeon Co., Ltd.) was used. Except for the above, a thermoplastic elastomer 2 was obtained in the same manner as the thermoplastic elastomer 1 described above.
The amount of maleic anhydride introduced and the side chain introduction rate of the thermoplastic elastomer 3 were 0.63 mol%.

(Synthesis Example 4: Thermoplastic Elastomer 4)
Maleic anhydride-modified ethylene-propylene copolymer (manufactured by DSM Co., Ltd., prototype, ethylene content 60 mol%, maleic anhydride modification rate 0.8 mol%, weight average molecular weight 90,000) 100 g (maleic anhydride skeleton 22 .4 mmol), 1.88 g (22.4 mmol) of 4H-3-amino-1,2,4-triazole was added, and the mixture was heated and stirred at 170 ° C. for 30 to 35 minutes with a pressure kneader. Got.

<Examples 1-3 and Comparative Examples 1, 2>
The thermoplastic elastomers obtained in the above synthesis examples (simply referred to as “elastomer” in Table 1) 1 to 4 and HNBR1 were used alone.
<Examples 4 and 5 and Comparative Examples 3 and 4>
Each thermoplastic elastomer composition obtained by mixing the thermoplastic elastomer 1 or HNBR1 obtained in the above synthesis example with silica or carbon black by heating and mixing at 200 ° C. for 25 minutes in the combination (part by mass) shown in Table 1. Got.

In the present invention, the following silica and the like were used.
Silica: nipsil LP, manufactured by Nippon Silica Co., Ltd. Carbon black: Dia Black G, manufactured by Tokai Carbon Co., Ltd. Zinc oxide: Zinc Hana 3, manufactured by Shodo Chemical Industry Co., Ltd. Stearic acid: Bead stearic acid, Nippon Oil & Fats (stock)
Sulfur: powdered sulfur, manufactured by Karuizawa Refinery, vulcanization accelerator: dibenzothiazyl disulfide

  Each thermoplastic elastomer and thermoplastic elastomer composition obtained were evaluated for recyclability and oil resistance, and a tensile test. The results are shown in Table 2.

<Tensile test>
Hot pressing was performed at 180 ° C. for 10 minutes to prepare a sheet having a thickness of 2 mm. A No. 3 dumbbell-shaped test piece was punched from the sheet, and a tensile test was performed at a tensile speed of 500 mm / min in accordance with JIS K 6251. The 100% modulus (M100), 300% modulus (M300), breaking strength (T _B ) and breaking elongation (E _B ) were measured at room temperature.

<Oil resistance>
About each said thermoplastic elastomer and thermoplastic elastomer composition, the test piece of length 25cm, width 3.4cm, thickness 0.2cm (volume 1.7cm < ³ >) was produced, and based on JISK6258-1993, it was 70. The volume change rate was measured by immersing in a test lubricant (JIS No. 3 oil) at 72 ° C. for 72 hours.

<Recyclability>
About each said thermoplastic elastomer and thermoplastic elastomer composition, after heat-pressing at 180 degreeC for 10 minute (s) and producing a sheet | seat of thickness 2mm, this sample is cut | disconnected finely and press-molded again, and the sample which is seamless and integrated It evaluated by the frequency | count which can be manufactured.
Evaluation was expressed as “◎” when it was repeatedly produced 10 times or more, and “x” when the integrated sample could not be produced again.

As is apparent from Table 2, the thermoplastic elastomer of the present invention (Examples 1 to 3) is superior to the thermoplastic elastomer 4 (Comparative Example 1) having an ethylene-propylene copolymer as the main chain. It is extremely excellent in oil resistance while maintaining recyclability, retains the same mechanical properties as vulcanized acrylonitrile-butadiene rubber (Comparative Example 2), and can further improve oil resistance, and It also had excellent recyclability not found in acrylonitrile-butadiene rubber.
In particular, when the amount of bound nitrile of the copolymer is 20% or more, the oil resistance is extremely excellent.
The same tendency was obtained for the thermoplastic elastomer compositions (Examples 4 and 5).

Claims (10)

To a copolymer containing acrylonitrile as a monomer,
A thermoplastic elastomer having a side chain containing a carbonyl-containing group and a nitrogen-containing heterocycle in a proportion of 0.1 to 50 mol% with respect to 100 mol% of the monomer constituting the copolymer.   The thermoplastic elastomer according to claim 1, wherein the copolymer is an acrylonitrile-butadiene copolymer or a hydrogenated acrylonitrile-butadiene copolymer. The thermoplastic elastomer according to claim 1 or 2, wherein the side chain contains a structure represented by the following formula (1).

Wherein A is a nitrogen-containing heterocyclic ring, B is a single bond; an oxygen atom, an amino group NR ′ (R ′ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms) or a sulfur atom; or these An organic group that may contain any atom or group of The thermoplastic elastomer according to any one of claims 1 to 3, wherein the side chain contains a structure represented by the following formula (2) or (3) bonded to the copolymer at the α-position or β-position. .

(Wherein A is a nitrogen-containing heterocyclic ring, B and D are each independently a single bond; an oxygen atom, an amino group NR ′ (R ′ is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms)) or A sulfur atom; or an organic group that may contain these atoms or groups.)   The thermoplastic elastomer according to any one of claims 1 to 4, wherein the nitrogen-containing heterocycle is a 5- or 6-membered ring.   The thermoplastic elastomer according to claim 5, wherein the nitrogen-containing heterocycle is a triazole ring, a thiadiazole ring, a pyridine ring, an imidazole ring or a hydantoin ring.   A thermoplastic elastomer composition containing the thermoplastic elastomer according to claim 1.   The thermoplastic elastomer composition according to claim 7, further comprising 1 to 200 parts by mass of carbon black and / or silica with respect to 100 parts by mass of the thermoplastic elastomer.   The thermoplastic elastomer or thermoplastic elastomer composition according to any one of claims 1 to 8, which is used for oil-resistant parts.   The thermoplastic resin according to any one of claims 1 to 6, wherein a compound having a cyclic acid anhydride group in the side chain and containing acrylonitrile as a monomer is reacted with a compound capable of introducing a nitrogen-containing heterocyclic ring. Elastomer production method.