阅读说明：本技术 树脂组合物 (Resin composition ) 是由 知野圭介 森永由浩 佐佐木裕平 石井隆文 岩崎俊之 于 2019-07-30 设计创作，主要内容包括：一种树脂组合物,其含有选自树脂(A)和树脂(B)中的至少1种树脂成分,所述树脂(A)具有侧链(a)并且玻璃化转变温度为25℃以下,所述侧链(a)含有具有含羰基的基团和/或含氮杂环的氢键性交联部位,所述树脂(B)在侧链上含有氢键性交联部位和共价键性交联部位并且玻璃化转变温度为25℃以下,并且所述树脂(A)和所述树脂(B)均是熔点为68℃～134℃且马来化率为0.5～2.5质量％的马来酸酐改性热塑性树脂与交联剂的反应物。(A resin composition comprising at least 1 resin component selected from a resin (A) having a side chain (a) containing a site of hydrogen bond crosslinking having a carbonyl group-containing group and/or a nitrogen-containing heterocycle and having a glass transition temperature of 25 ℃ or lower, and a resin (B) containing a site of hydrogen bond crosslinking and a site of covalent bond crosslinking on a side chain and having a glass transition temperature of 25 ℃ or lower, wherein the resin (A) and the resin (B) are both a reaction product of a maleic anhydride-modified thermoplastic resin having a melting point of 68 to 134 ℃ and a maleation rate of 0.5 to 2.5 mass% and a crosslinking agent.)

1. A resin composition comprising at least 1 resin component selected from a resin (A) having a side chain (a) containing a site of hydrogen bond crosslinking having a carbonyl group-containing group and/or a nitrogen-containing heterocycle and having a glass transition temperature of 25 ℃ or lower, and a resin (B) containing a site of hydrogen bond crosslinking and a site of covalent bond crosslinking on a side chain and having a glass transition temperature of 25 ℃ or lower, wherein the resin (A) and the resin (B) are both a reaction product of a maleic anhydride-modified thermoplastic resin having a melting point of 68 to 134 ℃ and a maleation rate of 0.5 to 2.5 mass% and a crosslinking agent.

2. The resin composition according to claim 1, wherein the crosslinking agent is a compound having at least 1 of a hydroxyl group, an amino group, an imino group, and a thiol group.

3. The resin composition according to claim 1 or 2, wherein the maleic anhydride-modified thermoplastic resin is a polyolefin-based resin modified with maleic anhydride.

4. The resin composition according to claim 3, wherein the polyolefin resin modified with maleic anhydride is a high-density polyethylene modified with maleic anhydride.

Technical Field

The present invention relates to a resin composition.

Background

Conventionally, in the field of resin compositions, various resins have been studied in order to exhibit properties suitable for the intended use. For example, Japanese patent laid-open No. 2002-60601 (patent document 1) discloses a polyester resin composition containing: (A) a thermoplastic polyester resin having a functional group functioning as a hydrogen bond donor; and (B) a compound having 2 or more functional groups functioning as hydrogen bond acceptors in the molecule. Further, Japanese patent laid-open publication No. 2002-146169 (patent document 2) discloses a polyester resin composition comprising: (A) a thermoplastic polyester resin having a functional group other than a carbonyl group which functions as a hydrogen bond acceptor; and (B) a compound having 2 or more functional groups functioning as hydrogen bond donors in the molecule. In addition, japanese patent application laid-open No. 2002-201265 (patent document 3) discloses a thermoplastic resin having a specific secondary amino group and/or a specific primary amino group at the end in the main chain, and further having a functional group other than the aforementioned secondary and primary amino groups, which functions as a hydrogen bond donor. Further, Japanese patent laid-open No. 2000-169527 (patent document 4) discloses a thermoplastic resin obtained by reacting a plastic polymer having a cyclic acid anhydride group in a side chain thereof with a heterocyclic amine-containing compound at a temperature at which the heterocyclic amine-containing compound and the cyclic acid anhydride group are chemically bonded, and examples 6 to 8 disclose thermoplastic resins obtained by reacting maleic anhydride-modified polypropylene (trade name "UMEX 1010" manufactured by Sanyo chemical Co., Ltd.) with 3-amino-1, 2, 4-triazole. However, the conventional resins and compositions using them described in the above patent documents 1 to 4 cannot sufficiently excel both in resistance to compression set and in fluidity, and cannot achieve both of these properties.

Documents of the prior art

Patent document

Japanese patent laid-open publication No. 2002-60601

Japanese patent laid-open publication No. 2002-146169

Japanese patent laid-open publication No. 2002-201265

Japanese patent laid-open No. 2000-169527

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made in view of the problems of the prior art, and an object of the present invention is to provide a resin composition which can satisfy both of the resistance to compression set and the flowability sufficiently excellent.

Means for solving the problems

The present inventors have conducted intensive studies in order to achieve the above object, and as a result, have found that both the resistance to compression set and the flowability are sufficiently excellent and simultaneously achieved by a resin composition containing at least 1 resin component selected from the group consisting of a resin (A) having a side chain (a) containing a hydrogen-bonding crosslinking site having a carbonyl-containing group and/or a nitrogen-containing heterocycle and a resin (B) containing a hydrogen-bonding crosslinking site and a covalent bonding crosslinking site in a side chain and having a glass transition temperature of 25 ℃ or less, and a crosslinking agent and a maleic anhydride-modified thermoplastic resin having a melting point of 68 to 134 ℃ and a maleation rate of 0.5 to 2.5 mass%, the present invention has been completed.

Specifically disclosed is a resin composition containing at least 1 resin component selected from a resin (A) and a resin (B), wherein the resin (A) has a side chain (a) which contains a hydrogen-bonding crosslinking site having a carbonyl-containing group and/or a nitrogen-containing heterocycle, the resin (B) has a hydrogen-bonding crosslinking site and a covalent-bonding crosslinking site on the side chain, and has a glass transition temperature of 25 ℃ or lower, and the resin (A) and the resin (B) are both a reaction product of a maleic anhydride-modified thermoplastic resin and a crosslinking agent, the melting point of the resin (A) and the melting point of the resin (B) being 68-134 ℃, and the maleic rate of the resin (A) and the resin (B) being 0.5-2.5 mass%.

Effects of the invention

According to the present invention, it is possible to provide a resin composition which is sufficiently excellent in both resistance to compression set and flowability and can achieve a balance therebetween.

Detailed Description

The present invention will be described in detail below based on preferred embodiments of the invention.

The resin composition of the present invention contains at least 1 resin component selected from the group consisting of the resin (A) and the resin (B), and the resin (A) and the resin (B) are both a reaction product of a maleic anhydride-modified thermoplastic resin having a melting point of 68 to 134 ℃ and a maleation rate of 0.5 to 2.5 mass% and a crosslinking agent.

The resin component of the present invention contains at least 1 resin selected from the group consisting of a resin (A) having a side chain (a) containing a hydrogen-bonding crosslinking site having a carbonyl-containing group and/or a nitrogen-containing heterocycle and having a glass transition temperature of 25 ℃ or lower, and a resin (B) having a hydrogen-bonding crosslinking site and a covalent-bonding crosslinking site on a side chain and having a glass transition temperature of 25 ℃ or lower. In the above-mentioned resins (A) to (B), "side chain" means a side chain and a terminal of the resin. The "side chain (a) having a hydrogen-bond-crosslinkable moiety having a carbonyl-containing group and/or a nitrogen-containing heterocycle" means that a carbonyl-containing group and/or a nitrogen-containing heterocycle (more preferably a carbonyl-containing group and a nitrogen-containing heterocycle) as a hydrogen-bond-crosslinkable moiety is chemically and stably bonded (covalently bonded) to an atom (usually a carbon atom) forming the main chain of the resin. The phrase "having a hydrogen bonding crosslinking site and a covalent bonding crosslinking site in a side chain" refers to the following concept: the present invention also includes a case where both of the hydrogen-bonding crosslinking site and the covalent crosslinking site are contained in a side chain of a resin by containing both of a side chain having a hydrogen-bonding crosslinking site (hereinafter sometimes referred to as "side chain (a')" for convenience) and a side chain having a covalent crosslinking site (hereinafter sometimes referred to as "side chain (b)" for convenience), and a case where both of the hydrogen-bonding crosslinking site and the covalent crosslinking site are contained in a side chain of a resin by containing both of the hydrogen-bonding crosslinking site and the covalent crosslinking site (side chain containing both of the hydrogen-bonding crosslinking site and the covalent crosslinking site in 1 side chain: such a side chain is sometimes referred to as "side chain (c)" for convenience hereinafter).

Further, from the viewpoint of improving stretchability, the resin component is more preferably at least 1 selected from the group consisting of resins (B) having a hydrogen-bonding crosslinking site and a covalent-bonding crosslinking site in the side chain and having a glass transition temperature of 25 ℃ or lower. Since the resins (a) to (B) are reactants of the maleic anhydride-modified thermoplastic resin and the crosslinking agent, the main chain (the type of the polymer (resin) forming the main chain portion) of the resins (a) to (B) in the resin component is derived from the main chain of the maleic anhydride-modified thermoplastic resin. The thermoplastic resins (main chains of maleic anhydride-modified thermoplastic resins) forming the main chain portions of the resins (a) to (B) will be described later.

The glass transition temperatures of the resins (a) to (B) are all 25 ℃ or lower as described above. In the present invention, the "glass transition temperature" is a glass transition temperature measured by Differential Scanning Calorimetry (DSC-Differential Scanning Calorimetry). In the measurement, the temperature increase rate was set to 10 ℃/min. By setting the glass transition temperature of the resin to 25 ℃ or lower, flexibility can be provided in a normal use temperature range (room temperature (25 ℃) or higher).

As described above, the resins (a) to (B) have, as side chains, at least 1 of the following three types of side chains: a side chain (a) having a hydrogen-bonding cross-linking site having a carbonyl-containing group and/or a nitrogen-containing heterocycle; a side chain (a') having a hydrogen bonding crosslinking site and a side chain (b) having a covalent bonding crosslinking site; and a side chain (c) having a hydrogen bonding crosslinking site and a covalent bonding crosslinking site. In the present invention, the side chain (c) can be said to function as both the side chain (a') and the side chain (b). Hereinafter, each side chain will be described.

< side chain (a'): side chain having Hydrogen-bond-Cross-linking site >

The side chain (a') having the above-mentioned hydrogen bonding crosslinking site is not particularly limited in structure as long as it has a group (for example, a hydroxyl group, a hydrogen bonding crosslinking site contained in the side chain (a) described later, or the like) capable of forming a crosslink by a hydrogen bond and forms a hydrogen bond based on the group. Here, the hydrogen-bonding cross-linking site is a site where molecules of the resin are cross-linked with each other by hydrogen bonding. Further, since the crosslinks by hydrogen bonds are formed only by an acceptor having hydrogen (e.g., a group containing an atom having an isolated electron pair) and a donor having hydrogen (e.g., a group having a hydrogen atom which forms a covalent bond with an atom having a large electronegativity), the crosslinks by hydrogen bonds cannot be formed unless both the acceptor having hydrogen and the donor having hydrogen are present between side chains of the respective molecules of the resin. Therefore, when both a hydrogen acceptor and a hydrogen donor are present between side chains of the respective molecules of the resin, a hydrogen-bonding cross-linking site is present in the system. In the present invention, since both a portion capable of functioning as a hydrogen acceptor (for example, a carbonyl group) and a portion capable of functioning as a hydrogen donor (for example, a hydroxyl group) are present between side chains of the respective molecules of the resin, the portion capable of functioning as a hydrogen acceptor and the portion capable of functioning as a hydrogen donor of the side chains can be determined as the hydrogen-bonding cross-linking site.

The hydrogen-bonding cross-linking site in the side chain (a') is more preferably a side chain (a) described later from the viewpoint of forming a stronger hydrogen bond. From the same viewpoint, the hydrogen-bonding site of the side chain (a') is more preferably a hydrogen-bonding site having a carbonyl group-containing group and a nitrogen-containing heterocycle.

< side chain (a): side chain having a site of hydrogen-bond crosslinkage having carbonyl-containing group and/or nitrogen-containing heterocycle >

The side chain (a) having a hydrogen-bond-crosslinkable moiety having a carbonyl-containing group and/or a nitrogen-containing heterocycle is not particularly limited as long as it has a side chain having a carbonyl-containing group and/or a nitrogen-containing heterocycle. The hydrogen-bonding crosslinking site preferably has a carbonyl group-containing group and a nitrogen-containing heterocycle.

The carbonyl group-containing group is not particularly limited as long as it is a carbonyl group-containing group, and specific examples thereof include an amide, an ester, an imide, a carboxyl group, a carbonyl group, a thioester group and the like. In the present invention, since both the resins (a) and (B) are a reaction product of the maleic anhydride-modified thermoplastic resin and the crosslinking agent, they have a group derived from the "maleic anhydride group" of the maleic anhydride-modified thermoplastic resin (depending on the kind of the crosslinking agent to be reacted, for example, an ester group, a carbonyl group, an amide group, an imide group, a carboxyl group, etc.).

When the side chain (a) has a nitrogen-containing heterocycle, the nitrogen-containing heterocycle may be introduced into the side chain (a) directly or via an organic group, and the structure thereof and the like are not particularly limited. The nitrogen-containing heterocyclic ring may contain a hetero atom other than a nitrogen atom, for example, a sulfur atom, an oxygen atom, a phosphorus atom, or the like in the heterocyclic ring, as long as the nitrogen atom is contained in the heterocyclic ring. The nitrogen-containing heterocycle may have a substituent. Here, when a nitrogen-containing heterocycle is used as the side chain (a), the hydrogen bond for forming a crosslink due to the heterocyclic structure is stronger, and the stretchability and impact resistance of the resin composition are further improved, which is preferable. The nitrogen-containing heterocycle is preferably a 5-membered ring and/or a 6-membered ring from the viewpoint of further enhancing the hydrogen bond, compression set and mechanical strength. The nitrogen-containing heterocyclic ring may be a nitrogen-containing heterocyclic ring obtained by condensing a nitrogen-containing heterocyclic ring with a benzene ring or a nitrogen-containing heterocyclic ring obtained by condensing nitrogen-containing heterocyclic rings. As the above-mentioned nitrogen-containing heterocycle, a known nitrogen-containing heterocycle (for example, nitrogen-containing heterocycles described in paragraphs [0054] to [0067] of Japanese patent application No. 5918878, or nitrogen-containing heterocycles described in paragraphs [0035] to [0048] of Japanese patent application laid-open No. 2017-206604) can be suitably used. The nitrogen-containing heterocycle may have a substituent. Examples of the nitrogen-containing heterocycle include pyrroline, pyrrolidone, indolone (2-indolone), indolihydroxy (3-indolone), dioxoindole, isatin, indolyl, phthalimidine, β -isoindigo, monoporphyrin, porphyrazine, azaporphyrin, phthalocyanine, hemoglobin, uroporphyrin, chlorophyll, phyllin, imidazole, pyrazole, triazole, tetrazole, benzimidazole, benzopyrazole, benzotriazole, imidazoline, imidazolone, imidazolidinone, hydantoin, pyrazoline, pyrazolone, indazole, pyridoindole, purine, cinnoline, pyrrole, pyrroline, indole, indoline, oxyindole (oxyindole), carbazole, phenothiazine, indolenine, isoindole, isoxazole, isothiazole, oxadiazole, thiadiazole, triazole, thiatriazole, phenanthroline, indoline, and oxoindole (oxyindole), carbazole, phenothiazine, indolene, isoindole, isoxazole, isothiazole, oxadiazole, thiadiazole, thiatriazole, and phenanthroline, Oxazines, benzoxazines, phthalazines, pteridines, pyrazines, phenazines, tetrazines, benzoxazoles, benzisoxazoles, phthalamides, benzothiazoles, benzofurazanes, pyridines, quinolines, isoquinolines, acridines, phenanthridines, benzanthracenes, naphthyridines, thiazines, pyridazines, pyrimidines, quinazolines, quinoxalines, triazines, histidines, triazolidines, melamines, adenine, guanine, thymines, cytosines, hydroxyethylisocyanurates, and derivatives thereof, and the like.

The nitrogen-containing heterocycle is preferably at least 1 selected from the group consisting of a triazole ring, an isocyanurate ring, a thiadiazole ring, a pyridine ring, an imidazole ring, a triazine ring and a hydantoin ring each of which may have a substituent, and more preferably at least 1 selected from the group consisting of a triazole ring, a thiadiazole ring, a pyridine ring, an imidazole ring and a hydantoin ring each of which may have a substituent, from the viewpoint of being excellent in cyclability, compression set, hardness and mechanical strength (particularly tensile strength).

Examples of the substituent which the nitrogen-containing heterocycle may have include a hydroxyl group, an amino group, an imino group, a carboxyl group, an isocyanate group, an epoxy group, an alkoxysilyl group, a thiol group (mercapto group), and the like. Further, as the above-mentioned substituent, an alkyl group such as a methyl group, an ethyl group, (i) propyl group, or a hexyl group; alkoxy groups such as methoxy, ethoxy, and (i) propoxy; a group containing a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.; a cyano group; an amino group; an imino group; an aromatic hydrocarbon group; an ester group; an ether group; an acyl group; a thioether group; and the like. The substitution position of the above-mentioned substituent is not particularly limited, and the number of the substituent is not limited.

In the side chain (a), when both the carbonyl-containing group and the nitrogen-containing heterocycle are contained, the carbonyl-containing group and the nitrogen-containing heterocycle may be introduced into the main chain as separate side chains, but preferably, the carbonyl-containing group and the nitrogen-containing heterocycle are introduced into the main chain as 1 side chain in which the carbonyl-containing group and the nitrogen-containing heterocycle are bonded through different groups. The structure of the side chain (a) may be, for example, the structure described in paragraphs [0068] to [0081] of japanese patent No. 5918878.

The side chain (a) is formed by the reaction of the maleic anhydride-modified thermoplastic resin and the crosslinking agent. As the crosslinking agent used for forming the side chain (a), a compound capable of reacting with a maleic anhydride group to form a hydrogen-bonded crosslinking site (hereinafter, may be referred to simply as "a compound forming a hydrogen-bonded crosslinking site") can be preferably used. As the "compound forming a hydrogen-bonding cross-linking site" which can be used as the above-mentioned cross-linking agent, a compound capable of introducing a nitrogen-containing heterocycle can be preferably used. Thus, the crosslinking agent preferably utilizes a "compound which forms a hydrogen-bonding crosslinking site (more preferably a compound capable of introducing a nitrogen-containing heterocycle)". The "compound capable of forming a hydrogen-bonding crosslinking site" (more preferably, a compound capable of introducing a nitrogen-containing heterocycle) "is preferably, for example, a compound having a substituent (for example, a hydroxyl group, a thiol group, an amino group, an imino group, or the like) which reacts with a maleic anhydride group, and more preferably a compound having at least 1 of a hydroxyl group, an amino group, an imino group, and a thiol group. Further, the above-mentioned compound having a substituent reactive with a maleic anhydride group (more preferably, a compound having at least 1 of a hydroxyl group, an amino group, an imino group, and a thiol group) is particularly preferably a compound having a nitrogen-containing heterocycle.

< side chain (b): side chain having covalently crosslinkable moiety

In the present specification, the "side chain (b) containing a covalently crosslinkable moiety" refers to the following side chain: contains a site for crosslinking each molecule of the resin forming the main chain by a covalent bond (covalent crosslinking site: a site for crosslinking polymers with each other by a chemically stable bond (covalent bond) such as at least 1 bond selected from amide, ester and thioester, which can be formed by reacting a maleic anhydride group with a crosslinking agent). Further, although the side chain (b) is a side chain having a covalently crosslinkable moiety, when it has a group capable of forming a hydrogen bond in addition to a covalently crosslinkable moiety and is crosslinked by a hydrogen bond between the side chains, it is utilized as the side chain (c) described later (when both a hydrogen donor and a hydrogen acceptor capable of forming a hydrogen bond are not included between the side chains of the respective molecules of the resin, for example, when only a side chain containing an ester group (-COO-) is present in the system, the group cannot function as a hydrogen-bonding crosslinkable moiety because a hydrogen bond is not particularly formed between the ester groups (-COO-). on the other hand, when the side chains of the respective molecules of the resin each contain both a hydrogen donor site and a hydrogen acceptor site having a hydrogen bond such as a carboxyl group or a triazole ring, since hydrogen bonds are formed between side chains of the respective molecules of the resin, the resin contains a site of hydrogen-bonding cross-linking. For example, when an ester group and a hydroxyl group coexist between side chains of the respective molecules of the resin and a hydrogen bond is formed between the side chains by the groups, a site forming the hydrogen bond becomes a hydrogen-bonding cross-linking site. Therefore, depending on the structure of the side chain (b), the kind of substituent of another side chain, and the like, the side chain (c) may be used. ). The "covalently crosslinkable moiety" as used herein refers to a moiety in which molecules of a resin are crosslinked by covalent bonds.

The side chain (b) containing the covalently crosslinkable moiety is not particularly limited, and is preferably a side chain containing a covalently crosslinkable moiety formed by reacting a maleic anhydride-modified thermoplastic resin with a crosslinking agent made of a compound capable of reacting with a maleic anhydride group (functional group) to form a covalently crosslinkable moiety (hereinafter, sometimes referred to as "compound forming a covalently crosslinkable moiety (covalent bond-forming compound)"). The crosslinking at the aforementioned covalently crosslinking site of such a side chain (b) is preferably formed by at least 1 bond selected from the group consisting of an amide, an ester and a thioester.

As the "compound forming a covalently crosslinkable site (a compound generating a covalent bond)" which can be used as the above-mentioned crosslinking agent, a compound having a substituent (for example, a hydroxyl group, a thiol group, an amino group, an imino group, or the like) which reacts with a maleic anhydride group is preferable, and a compound having at least 1 of a hydroxyl group, an amino group, and an imino group is more preferable. Further, the above-mentioned compound having a substituent reactive with a maleic anhydride group (more preferably, a compound having at least 1 of a hydroxyl group, an amino group, and an imino group) is particularly preferably a compound having a nitrogen-containing heterocycle.

Examples of the "compound forming a covalently crosslinkable site (compound generating a covalent bond)" which can be used as the above-mentioned crosslinking agent include: 1 polyamine compound having 2 or more amino groups and/or imino groups in the molecule (when having both amino groups and imino groups, these groups account for 2 or more in total); 1 a polyol compound having 2 or more hydroxyl groups in the molecule; 1 a polyisocyanate compound having 2 or more isocyanate (NCO) groups in the molecule; 1 a polythiol compound having 2 or more thiol groups (mercapto groups) in the molecule; and the like. Here, the "compound forming a covalently crosslinkable moiety (compound forming a covalent bond)" is a compound capable of introducing both the hydrogen-bonding crosslinkable moiety and the covalently crosslinkable moiety depending on the kind of the substituent group of the compound, the degree of progress of the reaction in the reaction of the compound, and the like (for example, when a compound having 3 or more hydroxyl groups is used as a crosslinking agent to form a crosslinked moiety by a covalent bond, depending on the degree of progress of the reaction, 2 hydroxyl groups react with a functional group (maleic anhydride group) of the maleic anhydride-modified thermoplastic resin, and the remaining 1 hydroxyl group remains as a hydroxyl group, and in this case, the moiety forming a hydrogen-bonding crosslink can also be introduced together). Therefore, the "compound forming a covalently crosslinkable moiety (compound forming a covalent bond)" as exemplified herein may include "a compound forming both a hydrogen-bonding crosslinkable moiety and a covalently crosslinkable moiety". From the above-mentioned viewpoints, in forming the side chain (b), the side chain (b) may be formed by appropriately selecting a compound from the "compounds forming covalently crosslinkable sites (compounds forming covalent bonds)", appropriately controlling the degree of progress of the reaction, or the like, depending on the intended design. Further, when the compound forming the covalently crosslinkable moiety has a heterocyclic ring, the hydrogen-bonding crosslinkable moiety can be produced more efficiently at the same time, and a side chain having the covalently crosslinkable moiety can be efficiently formed as the side chain (c) described later. Therefore, specific examples of the compound having the above-mentioned heterocycle are described as preferable compounds for producing the side chain (c), particularly together with the side chain (c). The side chain (c) may be a preferred form of the side chain such as the side chain (a) or the side chain (b) in view of its structure.

As the polyamine compound, the polyol compound, the polyisocyanate compound and the polythiol compound which can be used as the above-mentioned "compound forming a covalently crosslinkable moiety (compound forming a covalent bond)", known compounds (for example, compounds described in paragraphs [0094] to [0106] of Japanese patent application No. 5918878) can be suitably used.

< side chain (c): side chain having both Hydrogen-bond Cross-linking site and covalent bond Cross-linking site >

The side chain (c) is a side chain containing both a hydrogen bonding crosslinking site and a covalent bonding crosslinking site in 1 side chain. The site of hydrogen bonding crosslinking contained in the side chain (c) is the same as that described for the side chain (a'), and preferably the same as that of the side chain (a). The covalently crosslinkable moiety contained in the side chain (c) may be the same as the covalently crosslinkable moiety in the side chain (b) (the preferred crosslinking may be the same crosslinking).

The side chain (c) is preferably a side chain formed by the following method: the maleic anhydride-modified thermoplastic resin is reacted with a compound (compound having both a hydrogen bonding crosslinking site and a covalent bonding crosslinking site introduced) which reacts with the functional group (maleic anhydride group) of the maleic anhydride-modified thermoplastic resin to form both a hydrogen bonding crosslinking site and a covalent bonding crosslinking site.

The compound forming both the hydrogen-bonding crosslinking site and the covalent crosslinking site (compound into which both the hydrogen-bonding crosslinking site and the covalent crosslinking site are introduced) is preferably a compound having a substituent (for example, a hydroxyl group, a thiol group, an amino group, an imino group, or the like) that reacts with a maleic anhydride group, and more preferably a compound having at least 1 selected from the group consisting of a hydroxyl group, an amino group, an imino group, and a thiol group. Further, as the compound forming both of the hydrogen-bonding crosslinking site and the covalent crosslinking site (compound into which both of the hydrogen-bonding crosslinking site and the covalent crosslinking site are introduced), a compound having a heterocyclic ring (particularly, a nitrogen-containing heterocyclic ring) and capable of forming a covalent crosslinking site (compound forming a covalent bond) is preferable, and among them, a heterocyclic ring-containing polyol, a heterocyclic ring-containing polyamine, a heterocyclic ring-containing polythiol, and the like are more preferable. The heterocyclic ring-containing polyol, polyamine and polythiol may be those having a heterocyclic ring (particularly preferably a nitrogen-containing heterocyclic ring), and the same compounds as the polyol compound, the polyamine compound and the polythiol compound described in the above "compound capable of forming a covalently crosslinkable site (compound forming a covalent bond)" can be suitably used. Further, as the heterocycle-containing polyol, polyamine and polythiol, known ones (for example, those described in paragraph [0113] of Japanese patent No. 5918878) can be suitably used.

(structures preferred as covalently crosslinkable sites in side chains (b) to (c))

In the side chains (b) and/or (c), when the cross-linking at the covalently crosslinkable moiety contains a tertiary amino bond (-N ═ or an ester bond (-COO-), and these bond moieties also function as hydrogen-bonding cross-linking moieties, it is preferable from the viewpoint of forming a hydrogen bond with other hydrogen-bonding cross-linking moieties to make the cross-linking stronger. In this way, when a tertiary amino bond (-N ═) or an ester bond (-COO-) in a side chain having a covalently crosslinkable moiety forms a hydrogen bond with another side chain, the covalently crosslinkable moiety containing the tertiary amino bond (-N ═) or the ester bond (-COO-) further has a hydrogen-bonding crosslinkable moiety, and can function as the side chain (c).

As the compound capable of reacting with the maleic anhydride group which is a functional group in the maleic anhydride-modified thermoplastic resin to form a covalently crosslinkable moiety containing the tertiary amino bond and/or the ester bond (a compound capable of forming both a hydrogen-bonding crosslinkable moiety and a covalently crosslinkable moiety: 1 kind of the crosslinking agent), preferable examples of the compound include polyethylene glycol laurylamine (e.g., N, N-bis (2-hydroxyethyl) laurylamine), polypropylene glycol laurylamine (e.g., N, N-bis (2-methyl-2-hydroxyethyl) laurylamine), polyethylene glycol octylamine (e.g., N, N-bis (2-hydroxyethyl) octylamine), polypropylene glycol octylamine (e.g., N, N-bis (2-methyl-2-hydroxyethyl) octylamine), Polyethylene glycol stearylamine (e.g., N-bis (2-hydroxyethyl) stearylamine), polypropylene glycol stearylamine (e.g., N-bis (2-methyl-2-hydroxyethyl) stearylamine).

The side chain (b) and/or the side chain (c) can be crosslinked at the covalently crosslinkable site by, for example, the same structure as that described in paragraphs [0100] to [0109] of Japanese patent application laid-open No. 2017-206604. For example, as the side chain (b) and/or the side chain (c) in the previous covalent bond crosslinking site crosslinking, can be preferably used at least 1 type of the following general formula (1) - (3) in the representation of the structure (in the following structure, when containing a hydrogen bonding crosslinking site, the structure of the side chain is used as the side chain (c)).

In the above general formulae (1) to (3), E, J, K and L 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 which may contain the above atom or group, and G may contain an oxygen atom, a sulfur atom or a nitrogen atom, and is a linear, branched or cyclic hydrocarbon group having 1 to 20 carbon atoms. The substituent G is preferably a group represented by the following general formulae (111) to (114).

The side chains (a'), side chains (a), side chains (b), and side chains (c) have been described above, and the groups (structures) of the side chains in the above-mentioned resins can be confirmed by commonly used analytical means such as NMR and IR spectroscopy.

The resin (a) has a glass transition temperature of 25 ℃ or lower, and the resin (B) has a glass transition temperature of 25 ℃ or lower, the glass transition temperature of the side chain containing a hydrogen-bonding crosslinking site and a covalent-bonding crosslinking site (e.g., a resin having both a side chain (a') and a side chain (B) as side chains, or a resin having a side chain (c) as a side chain). Further, as the resin component of the present invention, 1 of the above-mentioned resins (a) to (B) may be used alone, or 2 or more of them may be used in combination.

The resin (B) may be a resin having both the side chain (a') and the side chain (B), or a resin having the side chain (c), and the hydrogen bonding site included in the side chain of the resin (B) is preferably a hydrogen bonding site having a carbonyl group-containing group and/or a nitrogen-containing heterocycle (more preferably a hydrogen bonding site having a carbonyl group-containing group and a nitrogen-containing heterocycle) from the viewpoint of forming a stronger hydrogen bond. The crosslinking at the covalently crosslinkable moiety contained in the side chain of the resin (B) is preferably formed by at least 1 type of bond selected from the group consisting of amide, ester and thiol, from the viewpoint that intermolecular interactions such as hydrogen bonding can be generated between the side chains containing the crosslinkable moiety.

The resins (A) to (B) of the present invention are each a reaction product of a maleic anhydride-modified thermoplastic resin having a melting point of 68 to 134 ℃ and a maleation rate of 0.5 to 2.5 mass% and a crosslinking agent.

The melting point of the maleic anhydride-modified thermoplastic resin used for forming the resins (a) to (B) is 68 to 134 ℃ (more preferably 70 to 130 ℃, and still more preferably 75 to 128 ℃). When the melting point of the maleic anhydride-modified thermoplastic resin is lower than the lower limit, the flowability tends to be lowered, and when the melting point exceeds the upper limit, the flowability tends to be too high. As the melting point, a value measured by Differential Scanning Calorimetry (DSC-Differential Scanning Calorimetry) is used. In the measurement of the melting point, the temperature increase rate was set to 10 ℃/min.

The maleic anhydride-modified thermoplastic resin has a maleation rate of 0.5 to 2.5 mass% (more preferably 0.6 to 2.4 mass%, and still more preferably 0.7 to 2.3 mass%). When the maleation rate is less than the lower limit, the resistance to compression set tends to be low, and when the maleation rate exceeds the upper limit, the resistance to compression set also tends to be low.

In the present invention, the value (unit: mass%) of the "maleation rate" is a value obtained by using the following [ method for measuring maleation rate ].

[ method for measuring Malylation ratio ]

First, 400mg of a maleic anhydride-modified thermoplastic resin to be measured was dissolved in 80mL of tetrahydrofuran (hereinafter, for convenience, may be abbreviated as "THF") to obtain a THF solution for measurement. Then, the THF solution for measurement was titrated with a 0.1 mol/L ethanol solution of potassium hydroxide (standard solution for volume analysis: 0.1 mol/L ethanol solution of potassium hydroxide with correction; or a commercially available product in which a factor (characteristic value: correction value) at least 3 decimal places was described) in which a factor at 3 decimal places or more was obtained. Here, the end point (neutralization point) is obtained by potentiometric titration using a machine. The factor (characteristic value: correction value) of 0.1 mol/L potassium hydroxide in ethanol may be determined by titration with an oxalic acid standard solution, or when a commercially available product from which the factor is determined is used, the factor described in a commercially available reagent (for example, the factor described in a test report sheet of the reagent) may be used as it is. Then, the same measurement (blank test) was carried out and titration was carried out except that the maleic anhydride-modified thermoplastic resin was not used, and the amount of the dropwise addition of the 0.1 mol/L potassium hydroxide ethanol solution (blank value) to 80mL of THF was also determined. Then, the acid value was calculated from the obtained titration value (amount of dropwise added) according to the following "calculation formula of acid value", and then the maleation rate was calculated from the obtained value of acid value according to the following "calculation formula of maleation rate", to obtain the maleation rate (% in unit: mass%).

< calculation formula of acid value >

[ acid value]＝(A-B)×M₁×C×f/S

(wherein A represents the amount of 0.1 mol/L potassium hydroxide solution added dropwise (titration value: mL) as required for neutralization of the solution for measurement), B represents the amount of 0.1 mol/L potassium hydroxide solution added dropwise (titration value (blank value: mL) under blank conditions (blank test) (M) obtained by the same measurement except that the maleic anhydride-modified thermoplastic resin was not used), and₁the molecular weight of potassium hydroxide (56.1 (constant)), C the concentration of potassium hydroxide in an ethanol solution of potassium hydroxide (0.1 mol/L (constant)), f the factor of the ethanol solution of potassium hydroxide (correction value: the factor described in a commercially available reagent (for example, the factor described in the report on the detection of the reagent) can be used as it is), and S the mass of the maleic anhydride-modified thermoplastic resin used in the measurement (400g (constant)). The unit of the "acid value" obtained by this calculation is "mgKOH/g". )

< formula for calculating Maltization Rate >

[ Maleinization Rate ]]Acid value]÷M₁×M₂÷1000×100÷2

(wherein the acid value is shown inThe value (unit: mgKOH/g) obtained by the above-mentioned "calculation formula of acid value", M₁Represents the molecular weight (56.1 (constant)) of potassium hydroxide, M₂The molecular weight of maleic anhydride (98.1 (constant)) is shown. The unit of "maleation rate" obtained by this calculation is "mass%". ).

As the main chain of the maleic anhydride-modified thermoplastic resin (the resin forming the main chain portion of the resins (a) to (B)), there can be used a resin appropriately selected from among so-called thermoplastic resins so that the melting point of the maleic anhydride-modified thermoplastic resin is 68 to 134 ℃ (note that the "thermoplastic resin" in the maleic anhydride-modified thermoplastic resin referred to in the present specification means a polymer having thermoplasticity and having a melting point of 68 ℃ or higher (preferably a polymer having a melting point in the range of 68 to 134 ℃), and means a thermoplastic polymer other than so-called "elastomer" or "rubber"). The main chain of the maleic anhydride-modified thermoplastic resin (resin forming the main chain portion of the resins (a) to (B)) is not particularly limited, but at least 1 selected from the group consisting of polyolefin-based resins, polyester-based resins, and polyamide-based resins is more preferable, and polyolefin-based resins are particularly preferable.

The polyolefin resin forming the main chain of the maleic anhydride-modified thermoplastic resin may be a polymer of an α -olefin or a resin made of a copolymer of an α -olefin and another copolymerizable monomer. Examples of the polyolefin-based resin include polyethylene (PE: High Density Polyethylene (HDPE), Medium Density Polyethylene (MDPE), Low Density Polyethylene (LDPE), linear polyethylene (L-LDPE)), ultrahigh molecular weight polyethylene (UHPE), ethylene-ethyl acrylate copolymer (EEA), ethylene-butyl acrylate copolymer (EBA), ethylene-methyl acrylate copolymer (EMA), and the like. Here, the high density polyethylene means that the density is 0.94g/m³The above polyethylene. By medium density polyethylene is meant a polyethylene having a density of 0.92g/m³Above but below 0.94g/m³The low density polyethylene means 0.91g/m³Above but below 0.92g/m³The polyethylene of (1).

The maleic anhydride-modified thermoplastic resin may be any modified product of maleic anhydride of a thermoplastic resin and satisfies the above-mentioned conditions of melting point and maleation rate, and can be easily produced by appropriately adjusting the kind and amount of raw materials so as to satisfy the above-mentioned conditions by a known method for producing a maleic anhydride-modified thermoplastic resin. Further, commercially available products can be suitably used as the maleic anhydride-modified thermoplastic resin as long as the above conditions are satisfied.

Further, among the above maleic anhydride-modified thermoplastic resins, polyolefin resins modified with maleic anhydride are more preferable, high-density polyethylene modified with maleic anhydride and linear polyethylene (L-LDPE) modified with maleic anhydride are still more preferable, and high-density polyethylene modified with maleic anhydride is particularly preferable.

The crosslinking agent is not particularly limited as long as it is capable of reacting with the maleic anhydride group in the maleic anhydride-modified thermoplastic resin to form either of the resins (a) and (B), and a compound capable of reacting with the maleic anhydride group to form various crosslinking sites (a compound capable of forming a desired side chain) may be appropriately selected depending on the desired design.

The crosslinking agent preferably includes the aforementioned "compound capable of forming a hydrogen-bonding crosslinking site (more preferably, a compound capable of introducing a nitrogen-containing heterocycle)" and "compound capable of forming a covalent crosslinking site (compound capable of forming a covalent bond)". In addition, from the viewpoint of efficient reaction progress, the crosslinking agent is preferably a compound having at least 1 of a hydroxyl group, an amino group, an imino group, and a thiol group. Further, as the compound having at least 1 of a hydroxyl group, an amino group, an imino group and a thiol group, a compound having a nitrogen-containing heterocycle (as the nitrogen-containing heterocycle, at least 1 selected from a triazole ring, a polyisocyanurate ring, a thiadiazole ring, a pyridine ring, an imidazole ring, a triazine ring and a hydantoin ring is more preferable) (note that the "nitrogen-containing heterocycle" referred to herein is the same as the above-mentioned nitrogen-containing heterocycle including preferable ones). Examples of the compound having at least 1 of a hydroxyl group, an amino group, an imino group, and a thiol group include: tris (2-hydroxyethyl) isocyanurate; 2, 4-diamino-6-phenyl-1, 3, 5-triazine, methylguanamine, 3-amino-1, 2, 4-triazole, aminopyridine (2-, 3-, 4-), 3-amino-5-methylisoxazole, 2-aminomethylpiperidine, 1- (2-hydroxyethyl) imidazole, 2-butyl-5-hydroxymethylimidazole, 1, 3-dihydro-1-phenyl-2H-benzimidazole-2-thione, Chelidamic acid, kojic acid, 2, 5-dimercapto-1, 3, 4-thiadiazole, 1-phenyl-5-mercapto-1, 2, 3, 4-tetrazole, 1-methyl-5-mercapto-1, 2, 3, 4-tetrazole, trihydroxyethyltriazine, tris [ (3-mercaptopropionyloxy) -ethyl ] -isocyanurate, hydroxypyridine (2-, 3-, 4-), 1-hydroxybenzotriazole, 1- (2-aminoethyl) piperazine, bis (aminopropyl) piperazine, piperidineethanol (2-, 3-, 4-), piperidinemethanol (2-, 3-, 4-), pyridylethanol (2-, 3-, 4-), pyridinecarbinol (2-, 3-, 4-), benzoguanamine, 4-methyl-5- (2' -hydroxyethyl) thiazole, 1-hydroxymethyl-5, 5-dimethylhydantoin, melamine, mercaptopyridine (2- 3-, 4-). The above compounds may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

In addition, from the viewpoint of high reactivity and easy industrial availability, the crosslinking agent is preferably at least 1 compound selected from the group consisting of a nitrogen-containing compound which may have at least 1 substituent of a hydroxyl group, a thiol group, an amino group and an imino group, an oxygen-containing compound which may have at least 1 substituent of a hydroxyl group, a thiol group, an amino group and an imino group, and a sulfur-containing compound which may have at least 1 substituent of a hydroxyl group, a thiol group, an amino group and an imino group. The "compound capable of forming a hydrogen bonding crosslinking site (compound capable of introducing a nitrogen-containing heterocyclic ring)" and the "compound capable of forming a covalent bonding crosslinking site (compound capable of forming a covalent bond)" may be appropriately selected from known compounds (compounds described in Japanese patent laid-open Nos. 2017-57322 and 5918878) and used as long as they can react with a maleic anhydride group.

The crosslinking agent is preferably at least 1 selected from the following compounds: a triazole which may have at least 1 substituent of a hydroxyl group, a thiol group, an amino group, and an imino group; pyridine which may have at least 1 substituent of hydroxyl group, thiol group, amino group and imino group; thiadiazoles which may have at least 1 substituent of hydroxyl group, thiol group, amino group and imino group; imidazole which may have at least 1 substituent of hydroxyl group, thiol group, amino group and imino group; isocyanurates that may have at least 1 substituent of hydroxyl, thiol, amino, and imino groups; a triazine which may have at least 1 substituent of a hydroxyl group, a thiol group, an amino group, and an imino group; hydantoin which may have at least 1 substituent of a hydroxyl group, a thiol group, an amino group, and an imino group; tris (2-hydroxyethyl) isocyanurate; 2, 4-diamino-6-phenyl-1, 3, 5-triazine; pentaerythritol (pentaerythritol); a sulfonamide; and a polyether polyol.

The crosslinking agent is preferably tris (2-hydroxyethyl) isocyanurate, sulfonamide, pentaerythritol, 2, 4-diamino-6-phenyl-1, 3, 5-triazine, or polyether polyol, and more preferably pentaerythritol, 2, 4-diamino-6-phenyl-1, 3, 5-triazine, or tris (2-hydroxyethyl) isocyanurate, from the viewpoint of compression set resistance.

The method for obtaining the reaction product of the maleic anhydride-modified thermoplastic resin and the crosslinking agent is not particularly limited as long as it is a method capable of forming the resins (a) and (B) by reacting the maleic anhydride group in the maleic anhydride-modified thermoplastic resin with the functional group in the crosslinking agent (as long as it is a method capable of forming the crosslinked site described in the resins (a) and (B)), and the reaction may be appropriately performed depending on the kind of the crosslinking agent. For example, the following methods can be employed: the maleic anhydride-modified thermoplastic resin is plasticized and the added crosslinking agent is reacted with the maleic anhydride group at a temperature (for example, about 100 to 250 ℃) capable of reacting the maleic anhydride group with the crosslinking agent by a kneading machine such as a kneader while mixing (kneading) the maleic anhydride-modified thermoplastic resin.

The resin composition of the present invention may contain other components in addition to the above-mentioned resin components. As the other components, known components which can be used in the resin composition can be suitably used, and examples thereof include polymers other than the above-mentioned resin components (A) to (B), reinforcing agents (fillers), reinforcing agents for hydrogen bonding (fillers), fillers having an amino group introduced therein (hereinafter, simply referred to as "amino group-introduced fillers"), amino group-containing compounds other than the amino group-introduced fillers, compounds containing metal elements, maleic anhydride-modified polymers, antioxidants, pigments (dyes), plasticizers (softeners), thixotropy imparting agents, ultraviolet absorbers, flame retardants, solvents, surfactants (including leveling agents), process oils (paraffin oil, naphthene oil, aromatic oil, etc.), various oils other than the above-mentioned process oils, dispersants, dehydrating agents, rust inhibitors, adhesion imparting agents, antistatic agents, fillers, lubricating materials, processing aids (vulcanization-accelerating aids such as stearic acid and zinc oxide during vulcanization), and the like.

When the other components are contained, the content of the resin component in the resin composition of the present invention is preferably 1 to 99% by mass, more preferably 10 to 99% by mass, and still more preferably 20 to 99% by mass. When the content of the resin component in the resin composition is less than the lower limit, the effect obtained by the resin component tends to be low, while when the content of the resin component in the resin composition exceeds the upper limit, mixing tends to be difficult.

In addition, the resin composition of the present invention preferably further contains an α -olefin resin having no chemically bonded crosslinking site as the other component. The "α -olefin resin" as used herein refers to a homopolymer of α -olefin or a copolymer of α -olefin, and the "α -olefin" refers to an olefin having a carbon-carbon double bond at the α -position, and examples thereof include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, and 1-decene. As the above-mentioned α -olefin-based resin having no chemically bondable crosslinking site, for example, α -olefin-based resins described in paragraphs [0204] to [0214] of Japanese patent laid-open publication No. 2017-57322 can be preferably used.

As the α -olefin-based resin having no chemically bonded cross-linking site, for example, polypropylene, polyethylene, an ethylene-propylene copolymer, an ethylene-butene copolymer, and an ethylene-octene copolymer can be preferably used. As the α -olefin resin, among the above-mentioned α -olefin resins, α -olefin resins having a crystallinity of 10% or more (polypropylene, ethylene-propylene copolymer, ethylene-butene copolymer, polyethylene, polybutene, etc.) can be preferably used. The method for producing the above-mentioned α -olefin-based resin having no chemically bonded crosslinking site is not particularly limited, and a known method can be appropriately employed. Further, commercially available products may be used as the α -olefin-based resin. The above-mentioned α -olefin-based resin having no chemically bonded crosslinking site may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

When the α -olefin resin having no chemically bonded crosslinking site is contained in the resin composition, the content of the α -olefin resin is more preferably 500 parts by mass or less (more preferably 5 to 250 parts by mass, most preferably 35 to 200 parts by mass) per 100 parts by mass of the resin component. When the content of the α -olefin resin is less than the lower limit, the effect tends to be low, while when the content exceeds the upper limit, the hardness tends to be too high, and it tends to be difficult to impart sufficiently high flexibility to the resin composition.

Further, the resin composition of the present invention preferably contains a process oil as the other component, from the viewpoints that the fluidity of the composition can not be further improved, the workability in use becomes higher, and the hardness of the resin composition can be more effectively adjusted. The process oil includes paraffin oil, naphthenic oil, and aromatic oil, and among them, paraffin oil is more preferable. The paraffin oil is not particularly limited, and a known paraffin oil can be suitably used, and for example, a paraffin oil can be suitably used in the paragraph [0153 ] in Japanese patent laid-open publication No. 2017-57323]Paragraph [0157 ]]The paraffinic oil described in (1). Further, as the above-mentioned paraffin oil, the oil was subjected to a correlation ring analysis (n-D-M ring analysis) in accordance with ASTM D3238-85 to determine the percentage of the number of carbons of paraffin to the total number of carbons (paraffin part: CP) and naphthene respectivelyWhen the percentage of hydrocarbon carbon number to total carbon number (naphthene portion: CN) and the percentage of aromatic carbon number to total carbon number (aromatic portion: CA), the percentage of paraffin oil carbon number to total carbon number (CP) is preferably 60% or more. Further, from the viewpoint of fluidity and safety, the paraffin oil preferably has a dynamic viscosity at 40 ℃ of 10mm as measured in accordance with JIS K2283 (published in 2000)²Second to 700mm²In seconds. Further, from the viewpoint of fluidity and safety, the aniline point of the paraffin oil is preferably 80 to 145 ℃ as measured by the U-tube method in accordance with JIS K2256 (published in 2013). Further, the methods for measuring the dynamic viscosity and aniline point described above can be adopted in the respective paragraphs [0153 ] of Japanese patent application laid-open No. 2017-57323]Paragraph [0157 ]]The method as described in (1). As the paraffin oil, commercially available products can be suitably used.

When the resin composition contains the paraffin oil, the content of the paraffin oil is preferably 10 to 10000 parts by mass, and particularly preferably 30 to 1000 parts by mass, per 100 parts by mass of the resin component. If the content of the paraffin oil is less than the lower limit, the content of the paraffin oil is too small, and the effect of improving fluidity and handling properties obtained by adding the paraffin oil tends to be insufficient.

In addition, the resin composition of the present invention preferably contains a styrene block copolymer having no chemically bonded crosslinking site as the other component from the viewpoint of preventing bleeding out when oil is used. Therefore, as the resin composition of the present invention, it is preferable to combine the styrene block copolymer containing the paraffin oil and the crosslinking site having no chemical bonding property. In this way, when the paraffin oil and the styrene block copolymer are contained in combination, the styrene block copolymer can be made to absorb the oil, the bleeding of the oil and the like can be more sufficiently suppressed, the fluidity of the obtained resin composition can be further improved, and the hardness can be more effectively adjusted. As the styrene block copolymer having no crosslinking site having chemical bonding property, the copolymers described in paragraphs [0156] to [0163] of Japanese patent laid-open publication No. 2017-57393 can be preferably used. The "styrene block copolymer" may be any polymer having a styrene block structure at any position.

The styrene block copolymer having no chemically bonded cross-linking site is preferably a styrene block copolymer having a styrene content of 10 to 50 mass% (more preferably 20 to 40 mass%) from the viewpoint of mechanical strength and oil absorption. In addition, the weight average molecular weight (Mw), the number average molecular weight (Mn), and the degree of dispersion of the molecular weight distribution (Mw/Mn) of the styrene block copolymer are preferably from 20 to 70 ten thousand (more preferably from 35 to 55 ten thousand), the Mn is preferably from 10 to 60 ten thousand (more preferably from 20 to 50 ten thousand), and the Mw/Mn is preferably 5 or less (more preferably from 1 to 3), from the viewpoint of mechanical strength and oil absorption. From the viewpoint of the performance of an elastomer (from the viewpoint of sufficiently exhibiting the performance of an elastomer), the glass transition temperature of the styrene block copolymer is preferably from-80 to-30 ℃ (more preferably from-70 to-40 ℃). The methods for measuring the various properties (Mw, Mn, etc.) described above are the methods described in paragraphs [0156] to [0163] of Japanese patent laid-open publication No. 2017-57393.

As the styrene block copolymer having no chemically bondable crosslinking site, known copolymers (for example, SIS, SEPS, SBS, SIBS, SEEPS, SEBS, etc.) can be suitably used, but from the viewpoints of molecular weight, industrial availability, and economic efficiency, a styrene-ethylene-propylene-styrene block copolymer (SEEPS), and a styrene-ethylene-butylene-styrene block copolymer (SEBS) are more preferable. The styrene block copolymer can be used alone in 1 kind, also can be combined with more than 2 kinds. Commercially available styrene block copolymers can be suitably used.

When the resin composition of the present invention contains the styrene block copolymer having no chemically bonded crosslinking site, the content of the styrene block copolymer is preferably 1 to 3000 parts by mass, more preferably 5 to 1000 parts by mass, per 100 parts by mass of the resin component. When the content ratio is less than the lower limit, the oil tends to bleed out when the oil is added, while when the content ratio exceeds the upper limit, the moldability tends to be lowered.

In addition, the resin composition of the present invention preferably contains a reinforcing agent (filler) as the other component from the viewpoint of improving the fracture physical properties (breaking strength, elongation at break). Examples of the reinforcing agent include silica, carbon black, clay (which may be organized clay), and calcium carbonate (which may be surface-treated calcium carbonate). Among these, clay is more preferable as the above-mentioned reinforcing agent. As the above-mentioned clay, known clays (for example, clays described in paragraphs [0146] to [0156] of Japanese patent No. 5918878, clays described in paragraphs [0146] to [0155] of Japanese patent laid-open No. 2017 and 057393, and the like) can be suitably used. Among the above clays, at least 1 kind selected from clays mainly composed of silicon and magnesium and organized clays is preferable from the viewpoint of high dispersibility, and organized clays are particularly preferable. When the resin composition of the present invention contains a reinforcing agent, the content of the reinforcing agent is preferably 20 parts by mass or less, and more preferably 0.01 to 10 parts by mass, per 100 parts by mass of the resin component. The above-mentioned reinforcing agents may be used singly in 1 kind or in combination in 2 or more kinds depending on the use.

The resin composition of the present invention preferably contains the above-mentioned antioxidant, antioxidant and the like, depending on the use thereof. The content of the antioxidant and the antioxidant is not particularly limited, but is preferably 20 parts by mass or less (more preferably 0.01 to 10 parts by mass) per 100 parts by mass of the resin component. Thus, other components can be used as appropriate according to the intended use and design. Such other components are not particularly limited to those described above, and known components used in polymer-containing compositions (for example, those described in paragraphs [0169] to [0174] of japanese patent No. 5918878, etc.) can be suitably used. The other components may be used alone in 1 kind or in combination of 2 or more kinds depending on the use.

The method for producing the resin composition is not particularly limited as long as the reaction product of the maleic anhydride-modified thermoplastic resin and the crosslinking agent can be contained in the composition. The above-mentioned method may be, for example, a method similar to the method described in each of the above paragraphs of Japanese patent application laid-open No. 2016-193970, in which the maleic anhydride-modified thermoplastic resin is reacted with the crosslinking agent, except that "the elastomeric polymer having a cyclic acid anhydride group in a side chain" described in the above-mentioned publication is used as "the maleic anhydride-modified thermoplastic resin" and "the raw material compound" described in the above-mentioned publication is used as "the crosslinking agent", to produce a resin composition containing the resin component made of the obtained reactant.

As a method for producing the above resin composition, for example, the following method can be preferably employed: the maleic anhydride-modified thermoplastic resin, the crosslinking agent, and other components (the styrene block copolymer having no chemically bonded crosslinking site, paraffin oil, the α -olefin resin having no chemically bonded crosslinking site, the additive, and the like) used as needed are mixed to obtain a resin composition containing the resin component. In the above method, it is preferable that the resin (a) and the resin (B) are prepared by reacting the maleic anhydride group in the maleic anhydride-modified thermoplastic resin with the functional group in the crosslinking agent to form a specific crosslink at the time of mixing. In the above method, the maleic anhydride-modified thermoplastic resin and the crosslinking agent can be reacted with each other at the time of mixing, and at the time of the reaction, the maleic anhydride group of the maleic anhydride-modified thermoplastic resin can be opened and a chemical bond can be formed with the crosslinking agent, so that the target "at least 1 resin component selected from the resin (a) and the resin (B)" can be efficiently formed depending on the kind of the component.

When the maleic anhydride-modified thermoplastic resin is reacted with the crosslinking agent by the above method, the amount of the crosslinking agent to be used is preferably 0.1 to 10 parts by mass, more preferably 0.2 to 5.0 parts by mass, based on 100 parts by mass of the maleic anhydride-modified thermoplastic resin. If the amount of the crosslinking agent added (based on the amount of parts by mass) is less than the lower limit, the crosslinking density tends not to increase and desired physical properties do not appear because the amount of the crosslinking agent added is too small, while if the amount exceeds the upper limit, the amount added is too large, the branching tends to increase (the amount of the crosslinking agent is too large, the proportion of the crosslinking agent not participating in crosslinking increases), and the crosslinking density tends to decrease.

In the above method, the temperature condition for reacting the maleic anhydride-modified thermoplastic resin with the crosslinking agent (for opening the ring of the maleic anhydride group) is not particularly limited as long as it is adjusted to a temperature at which the reaction is possible depending on the kind of the crosslinking agent, and the temperature is preferably set to 100 to 250 ℃, more preferably 120 to 230 ℃ from the viewpoint of softening the crosslinking agent and rapidly advancing the reaction, for example. The mixing method for carrying out the above reaction is not particularly limited, and a known method of mixing using a roller, a kneader, or the like can be suitably used. When other components are added, the order of addition of each component is not particularly limited, and may be appropriately changed depending on the kind of the component used. For example, when the styrene block copolymer having no chemically bonded cross-linking site, the paraffin oil, and the α -olefin resin having no chemically bonded cross-linking site are added as other components in the production of the resin composition, the following method can be employed. For example, the following method can be employed: first, the styrene block copolymer and the paraffin oil are mixed at a temperature of 100 to 250 ℃ to obtain a mixture, and then the mixture is subjected to a thermal treatment, the maleic anhydride-modified thermoplastic resin and the alpha-olefin resin are added under the temperature condition, mixed and plasticized, and a crosslinking agent is added under the temperature condition and mixed, the maleic anhydride-modified thermoplastic resin and the crosslinking agent are reacted with each other to obtain a resin composition containing a reaction product of the maleic anhydride-modified thermoplastic resin and the crosslinking agent, the styrene block copolymer, the paraffin oil, and the α -olefin resin (when other components such as the reinforcing agent (filler) and the antioxidant are further contained, the components may be appropriately added and mixed at an arbitrary stage depending on the components to be used). The amount of addition of these other components may be appropriately changed according to the design of the object (for example, the amount of addition may be appropriately set so as to fall within the above-described preferable content range).

Examples

The present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to the following examples.

First, the resin types, abbreviations, properties and the like of the maleic anhydride-modified thermoplastic resins used in the examples are shown in table 1. In tables 2 to 5, the maleic anhydride-modified thermoplastic resins used in the examples and the like are shown by the abbreviations shown in table 1 for convenience. The "maleation rate" shown in table 1 is a value obtained by the above-mentioned [ method for measuring maleation rate ] (in addition, as a potential difference automatic titration apparatus, a product name "AT-710M" manufactured by kyoto electronics industries co., ltd. is used, and as an ethanol solution of 0.1 mol/L potassium hydroxide, a product name "potassium hydroxide ethanol solution" manufactured by Merck co., ltd. the correction value (factor) of the ethanol solution of 0.1 mol/L potassium hydroxide used in this way was confirmed from a detection report of the solution, and the result was 1.00). The "melting point" shown in Table 1 is a value (value obtained by Differential Scanning Calorimetry (DSC)) measured using 0.01g of each resin and a differential scanning calorimeter (trade name "DSC 7000X" manufactured by Hitachi High-Tech Science corporation) with the temperature rise rate set at 10 ℃/min.

TABLE 1

Next, a method for evaluating the properties of the resin composition obtained in each example and the like described later will be described.

< Melt Flow Rate (MFR) >

The melt flow rate (MFR, unit: g/10 min) was measured by the method B described in JIS K6922-2 (published 2010) using the resin compositions obtained in the examples and comparative examples. That is, the following method is used: using the resin compositions obtained in each example and each comparative example, respectively, as a Melt index measuring device, 3G of the resin composition was added to the furnace body of the device under the trade name of "Melt index G-01" manufactured by seiko co, and then the temperature was set to 230 ℃ and held for 5 minutes, and then the load was 5kg while maintaining 230 ℃, under which condition the mass (G) per unit time of the resin composition flowing out from the opening (opening having a diameter of 1 mm) of the cylindrical opening member having a diameter of 1mm and a length of 8mm connected to the lower part of the furnace body (the mass of the resin composition flowing out was measured after starting the load after setting the temperature to 230 ℃ and holding for 5 minutes in the furnace body) was measured, and converted into the mass (G) of the resin composition flowing out in 10 minutes.

< compression Set (C-Set) >

Using the resin compositions obtained in each example and each comparative example, first, a sheet was prepared so that the thickness of the sheet became about 2mm by hot-pressing the resin compositions at 200 ℃ for 10 minutes. The sheet thus obtained was punched out into a disk shape having a diameter of 29mm and 7 pieces were stacked, and a sample was prepared so that the height (thickness) became 12.5. + -. 0.5 mm. The sample thus obtained was compressed by 25% using a special jig, and the compression set (unit:%) after being left at 70 ℃ for 22 hours was measured according to JIS K6262 (published in 2013). Further, as the compression apparatus, a product name "vulcanized rubber compression set tester SCM-1008L" manufactured by Dumbbell corporation was used.

(examples 1 to 9 and comparative examples 1 to 9)

In examples 1 to 9 and comparative examples 1 to 9, resin compositions were produced by adjusting the amounts of the respective components to be used in accordance with the compositions shown in tables 2 to 3 below, and by performing the "production process of a resin composition" described later. Further, the numerical values of the compositions in tables 2 to 3 below are values (parts by mass) in terms of 100 parts by mass of the used amount of the maleic anhydride-modified thermoplastic resin in examples and the like, and the used amount of the maleic anhydride-modified thermoplastic resin in examples 1 to 9 and comparative examples 1 to 9 is 8g in all cases.

< Process for producing resin composition >

First, a styrene-ethylene-butylene-styrene block copolymer (trade name "G1651 HU" manufactured by Clayton Polymer Japan, and a styrene content of 33 mass%: hereinafter, sometimes referred to as "SEBS") was charged into a pressure kneader, and mixed at 180 ℃ while paraffin oil (trade name "YUBASE 8J" manufactured by SK Lubricant Japan) was added dropwise to the pressure kneader, and the SEBS and the paraffin oil were mixed for 1 minute. Then, a maleic anhydride-modified thermoplastic resin (in each of examples and comparative examples, any one of TP (1) to (18) shown in Table 1 was used, respectively), an ethylene-butene copolymer (trade name "Tuffmer DF 7350" manufactured by Mitsui chemical Co., Ltd.: hereinafter sometimes referred to as "EBM"), a high-density polyethylene (trade name "HJ 590N" manufactured by Nippon polyethylene Co., Ltd.: hereinafter sometimes referred to as "HDPE") and an antioxidant (trade name "AO-50" manufactured by Adeka Co., Ltd.) were further added to the pressure kneader, and the mixture was mixed (kneaded) at 180 ℃ for 2 minutes to plasticize the mixture, thereby obtaining a mixture. Then, an organized clay (trade name "Esven WX" manufactured by Hojun corporation) was added to the mixture in the pressure kneader, and after mixing (kneading) at 180 ℃ for 4 minutes, tris (2-hydroxyethyl) isocyanurate (trade name "TANAC P" manufactured by sunstar industries) was added as a crosslinking agent, and mixing (kneading) was performed at 180 ℃ for 8 minutes, thereby producing a resin composition.

The measured values of the properties (MFR and C-Set) of the resin compositions obtained in the examples and comparative examples are shown in tables 2 to 3, respectively. Here, when MFR is 300g/10 min or more, MFR is indicated as "excessive". In the following tables, in the "evaluation of the maleation rate" of the maleic anhydride-modified thermoplastic resin, a condition that the maleation rate is in the range of 0.5 to 2.5 mass% is denoted as "S", and a condition that the maleation rate is not in the range of 0.5 to 2.5 mass% is denoted as "F". In the following tables, in the "evaluation of melting point" of the maleic anhydride-modified thermoplastic resin, the condition that the melting point is in the range of 68 to 134 ℃ is represented as "S", and the condition that the melting point is not in the range of 68 to 134 ℃ is represented as "F". Therefore, in the tables, the maleic anhydride-modified thermoplastic resin having a melting point of 68 to 134 ℃ and a maleation rate of 0.5 to 2.5 mass% in the present invention is referred to as "S" in both the evaluation of the maleation rate (the condition of the maleation rate) and the evaluation of the melting point (the condition of the melting point ").

TABLE 2

TABLE 3

(examples 10 to 11 and comparative examples 10 to 12)

A resin composition was produced in the same manner as in the "production process of a resin composition" used in examples 1 to 9 and comparative examples 1 to 9 described above except that pentaerythritol (trade name "Neulyzer P" manufactured by japan synthetic chemical corporation) was used as the crosslinking agent instead of tris (2-hydroxyethyl) isocyanurate and the amounts of the respective components used were adjusted so that the compositions (parts by mass) became the compositions described in table 4 (in each of examples and comparative examples, the amount of the maleic anhydride-modified thermoplastic resin used was set to 8 g). The measured values of the properties (MFR and C-Set) of the resin compositions obtained in examples and comparative examples are shown in Table 4 (in the case where the MFR is 300g/10 min or more, the MFR is indicated as "excessive"). The contents of the items concerning "evaluation of maleation rate" and "evaluation of melting point" are as described above.

TABLE 4

(examples 12 to 13 and comparative examples 13 to 15)

Resin compositions were produced in the same manner as in the "production process of resin compositions" used in examples 1 to 9 and comparative examples 1 to 9, except that 2, 4-diamino-6-phenyl-1, 3, 5-triazine (trade name "benzoguanamine", manufactured by japan catalyst corporation) was used as a crosslinking agent instead of tris (2-hydroxyethyl) isocyanurate and the amounts of the respective components used were adjusted so that the compositions (parts by mass) were the compositions described in table 5 (in each of examples and comparative examples, the amount of maleic anhydride-modified thermoplastic resin used was set to 8 g). The measured values of the properties (MFR and C-Set) of the resin compositions obtained in examples and comparative examples are shown in Table 5 (when the MFR is 300g/10 min or more, the MFR is indicated as "excessive"). The contents of the items concerning "evaluation of maleation rate" and "evaluation of melting point" are as described above.

TABLE 5

As is clear from the results shown in tables 2 to 5, the resin compositions (examples 1 to 13) containing the reaction product of the maleic anhydride-modified thermoplastic resin and the crosslinking agent, which had a melting point of 68 to 134 ℃ and a maleation rate of 0.5 to 2.5 mass%, all had a compression Set (C-Set) of 43% or less and a melt index (MFR) of 10 to 200g/10 min. Thus, not only the resin compositions obtained in examples 1 to 13 had a compression set of 43% or less and a sufficiently high resistance to compression set, but also the Melt Flow Rate (MFR), which is an index of fluidity, was in the range of 10 to 200g/10 min, so that fluidity, which is the workability of the resin composition, was sufficiently ensured, and both the resistance to compression set and the fluidity were satisfied at a high level. When the compression Set (C-Set) is 43% or less, the molded article obtained from the composition can be sufficiently suppressed in deformation even after long-term use, and is excellent in shape retention and recovery. When the Melt Flow Rate (MFR) is less than 10g/10 min, the fluidity is too low, and it is difficult to use a molding method such as injection molding at the time of molding, and the workability of molding or the like cannot be sufficiently obtained, whereas when the MFR exceeds 200g/10 min, the fluidity becomes too high, and the workability is rather lowered, and at the same time, extrusion molding cannot be sufficiently performed. Therefore, the compression set is 43% or less, and the melt index (MFR) is 10 ~ 200g/10 minutes of the range of resin composition can be said to the compression set resistance and fluidity of 2 kinds of excellent resin composition. It is apparent that the glass transition temperature of the reaction product of the maleic anhydride-modified thermoplastic resin and the crosslinking agent contained in the resin compositions obtained in the examples is 25 ℃ or lower based on the type of the resin (HDPE or LLDPE) to be the main chain and the glass transition temperature of the maleic anhydride-modified thermoplastic resin (see table 1).

In contrast, in the case of the resin compositions (comparative examples 1 to 15) containing the maleic anhydride-modified thermoplastic resin and the crosslinking agent reactant, which do not satisfy either or both of the condition (hereinafter referred to as "condition (I)") that the melting point is in the range of 68 to 134 ℃ and the condition (hereinafter referred to as "condition (II)") that the maleation rate is in the range of 0.5 to 2.5 mass%, the melt index (MFR) cannot be set in the range of 10 to 200g/10 min while the compression set of the composition is set to 43% or less. Thus, the resin composition containing a reaction product of the maleic anhydride-modified thermoplastic resin and the crosslinking agent, which does not satisfy either or both of the conditions (I) and (II), cannot sufficiently have excellent properties of resistance to compression set and fluidity, and cannot achieve both of these properties.

Industrial applicability

As described above, according to the present invention, it is possible to provide a resin composition which is sufficiently excellent in both resistance to compression set and flowability and can achieve a balance therebetween. Therefore, the resin composition of the present invention is particularly useful as a material for producing a resin product used for applications such as daily necessities, automobile parts, electric appliances, industrial parts, and the like.