Crosslinkable polyester elastomer resin composition

Abstract

The present disclosure was invented in light of the current circumstances, and addresses the problem of providing a highly heat-resistant crosslinkable polyester elastomer resin composition that achieves both hot rigidity and heat aging resistance in a high-temperature environment while maintaining flexibility and mechanical properties as an elastomer material. This crosslinkable polyester elastomer resin composition containing a polyester elastomer resin (A) is characterized in that: the polyester elastomer resin (A) has a hard segment and a soft segment; the hard segment is formed from a polyester containing an aromatic dicarboxylic acid and an aliphatic diol as constituent components; and the insoluble content obtained after the polyester elastomer resin composition is heat-treated at 240°C for 1 hour and subsequently heated in NMP at 150°C for 3 hours is 10 mass% or more.

Description

Crosslinkable polyester elastomer resin composition

[0001] This disclosure relates to a highly heat-resistant, crosslinkable polyester elastomer resin composition containing a polyester elastomer resin that maintains flexibility and mechanical properties as a thermoplastic elastomer material while simultaneously achieving high hot rigidity and heat aging resistance in high-temperature environments.

[0002] In recent years, there has been a growing trend to replace metal and rubber parts with thermoplastic resins in automobiles and home appliances. Furthermore, with the increasing performance of automobiles and home appliances, the distance between parts is decreasing, and resin parts are increasingly exposed to extremely high temperatures. Given these development trends, there is a strong demand for the development of thermoplastic resin compositions that possess both heat resistance and flame retardancy.

[0003] In response to the above requirements, thermoplastic polyester elastomer resins such as polyester polyether type, polyester polyester type, and polyester polycarbonate type are widely used as materials with excellent heat resistance and mechanical properties.

[0004] In particular, among the thermoplastic polyester elastomer resins, the polyester polycarbonate type has excellent heat aging resistance and oil swelling resistance, and there are many practical examples of its use in applications requiring a very high level of heat resistance (see, for example, Patent Documents 1 to 5).

[0005] However, because the aforementioned polyester polycarbonate type thermoplastic polyester elastomer resin is a thermoplastic resin, its usable temperature range is limited to the crystalline melting point of the hard segments that constitute the thermoplastic polyester elastomer resin. In reality, even with the polyester polycarbonate type, the development of a material that can be used in the high-temperature range of around 200°C has not yet been achieved.

[0006] While the melting point of thermoplastic polyester elastomer resins can be controlled to some extent by increasing the proportion of hard segment components or adjusting the blockiness (chain length), it is not possible to exceed the melting point potential caused by the type of hard segment component. Even if the heat aging resistance caused by soft segments can be improved, this has not yet led to an expansion of the usable temperature range of molded articles obtained using thermoplastic polyester elastomer resins.

[0007] To address the above issues, Patent Documents 6 to 8 disclose a method for crosslinking a molded article (e.g., a cable, a bellows-type molded article, etc.) obtained using a thermoplastic polyester elastomer resin that satisfies specific constituent requirements by irradiating the article with an electron beam. This method requires an expensive process involving irradiation with a high-energy electron beam, which imposes significant process limitations on industrial applications. For example, while short-term or long-term improvements in heat resistance in high-temperature environments have been achieved, these are either short-term or long-term effects only, and achieving both short-term and long-term effects simultaneously has not been accomplished. Furthermore, Patent Document 8, which discusses long-term heat resistance improvement, has a low usable temperature of 150°C, which is insufficient to satisfy the performance requirements and demands in the high-temperature range of around 200°C that are practically necessary.

[0008] Japanese Patent Publication No. 7-39480, Japanese Patent Publication No. 10-182782, Japanese Patent Publication No. 2001-206939, Japanese Patent Publication No. 2001-240663, Japanese Patent Publication No. 4244067, Japanese Patent Publication No. 3663275, Japanese Patent Publication No. 2014-196501, Japanese Patent Publication No. 2023-49227

[0009] This disclosure was conceived in light of the current situation, and aims to provide a highly heat-resistant, crosslinkable polyester elastomer resin composition that achieves both hot rigidity in high-temperature environments and resistance to heat aging while maintaining flexibility and mechanical properties as a thermoplastic elastomer material.

[0010] To achieve the above objective, the present inventors conducted diligent research and found that a polyester elastomer resin composition having an insoluble content of a predetermined amount or more after a specific heat treatment exhibits thermoplasticity while also forming a sufficiently cross-linked structure upon heating. Therefore, it is possible to achieve both high heat resistance, high hot rigidity in high-temperature environments, and resistance to heat aging while maintaining flexibility and mechanical properties, thus completing the present invention. The present invention is described below.

[0011] [1] A crosslinkable polyester elastomer resin composition containing a polyester elastomer resin (A), wherein the polyester elastomer resin (A) has a hard segment and a soft segment, the hard segment is formed from a polyester containing an aromatic dicarboxylic acid and an aliphatic diol as constituent components, and the insoluble content after heating the polyester elastomer resin composition at 240°C for 1 hour and then heating it in NMP at 150°C for 3 hours is 10% by mass or more. [2] The crosslinkable polyester elastomer resin composition according to [1] that satisfies one or more of the following requirements (i) to (v): (i) The soft segment of the polyester elastomer resin (A) contains a carbonate bond and an ester bond. (ii) One or both of the hard segment and the soft segment of the polyester elastomer resin (A) contain an unsaturated bond. (iii) One or both of the hard segment and the soft segment of the polyester elastomer resin (A) have a branched skeleton. (iv) The acid value of the polyester elastomer resin (A) is 80 to 200 eq / ton. (v) The crosslinkable polyester elastomer resin composition contains catalyst (B). [3] The crosslinkable polyester elastomer resin composition according to [1] or [2] that satisfies the following requirements (i) and (vi): (i) The soft segment of the polyester elastomer resin (A) contains carbonate bonds and ester bonds. (vi) The soft segment of the polyester elastomer resin (A) contains unsaturated bonds. [4] The crosslinkable polyester elastomer resin composition according to [1] or [2] that satisfies the following requirements (iii) and (v): (iii) One or both of the hard segment and the soft segment of the polyester elastomer resin (A) have a branched skeleton. (v) The crosslinkable polyester elastomer resin composition contains catalyst (B). [5] The crosslinkable polyester elastomer resin composition according to [1] or [2], satisfying the following requirements (iv) and (v).(iv) The acid value of the polyester elastomer resin (A) is 80 to 200 eq / ton. (v) The crosslinkable polyester elastomer resin composition contains catalyst (B). [6] The crosslinkable polyester elastomer resin composition according to [1] or [2] that satisfies the following requirements (vii) and (viii): (vii) The hard segment of the polyester elastomer resin (A) contains unsaturated bonds. (viii) The hard segment of the polyester elastomer resin (A) has a branched skeleton. [7] The crosslinkable polyester elastomer resin composition according to any one of [1] to [6], wherein the polyester elastomer resin (A) has 20 to 85% by mass of the hard segment and 15 to 80% by mass of the soft segment. [8] The crosslinkable polyester elastomer resin composition according to any one of [1] to [7], wherein the hard segment of the polyester elastomer resin (A) contains one or both of a trifunctional or more polycarboxylic acid and a trifunctional or more polyol as constituent units, thereby having a branched skeleton. [9] The crosslinkable polyester elastomer resin composition according to any one of [1] to [8], wherein the carboxylic acid component of the hard segment of the polyester elastomer resin (A) contains 0.5 to 2 mol% of a trifunctional or more polycarboxylic acid.

[10] The crosslinkable polyester elastomer resin composition according to any one of [1] to [9], wherein the carboxylic acid component of the hard segment or soft segment of the polyester elastomer resin (A) contains 3 to 20 mol% of an unsaturated dicarboxylic acid.

[11] The crosslinkable polyester elastomer resin composition according to [2], wherein the catalyst (B) contains one or more catalysts selected from the group consisting of tetrabutyl titanate, dodecylbenzenesulfonic acid, and ammonium dodecylbenzenesulfonate.

[12] The polyester elastomer resin composition is heat-treated at 240°C for 1 hour, and then the storage modulus E' at 220°C obtained by dynamic viscoelasticity measurement in accordance with JIS K7244 is 1.0 × 10. 4

[13] A crosslinkable polyester elastomer resin composition according to any one of [1] to

[11] , wherein the pressure is Pa or higher.

[14] A molded article formed from the crosslinkable polyester elastomer resin composition according to any one of [1] to

[13] .

[15] A crosslinked molded article formed from the crosslinkable polyester elastomer resin composition according to any one of [1] to

[13] .

[16] An extruded article formed from the crosslinkable polyester elastomer resin composition according to any one of [1] to

[13] .

[17] A coating material formed from the crosslinkable polyester elastomer resin composition according to any one of [1] to

[13] .

[0012] The crosslinkable polyester elastomer resin according to this disclosure is thermoplastic and exhibits a moderate melt flow rate, making it suitable for heat molding. Furthermore, a three-dimensional crosslinked structure is sufficiently formed by heat treatment for a predetermined time, resulting in high heat resistance that maintains flexibility and mechanical properties while simultaneously achieving both hot rigidity and heat aging resistance in high-temperature environments. Therefore, the crosslinkable polyester elastomer resin according to this disclosure is industrially very useful as a material that can replace metal materials that can be exposed to extremely high temperatures.

[0013] The crosslinkable polyester elastomer resin composition relating to this disclosure contains polyester elastomer resin (A). Hereinafter, the crosslinkable polyester elastomer resin composition may be simply referred to as the resin composition. In this disclosure, the numerical range "x to y" includes both x and y.

[0014] 1. Polyester elastomer resin (A) Polyester elastomer resin (A) is formed by bonding hard segments and soft segments, which are made from a polyester containing aromatic dicarboxylic acid and aliphatic diol as constituent components.

[0015] (1) Hard segment The hard segment constituting the polyester elastomer resin (A) is formed from a polyester in which a carboxylic acid component and an alcohol component are ester-bonded, the carboxylic acid component includes an aromatic dicarboxylic acid, and the alcohol component includes an aliphatic diol. In this disclosure, polycarboxylic acid means a carboxylic acid compound having three or more carboxyl groups per molecule, and polyol means an alcohol compound having three or more hydroxyl groups per molecule.

[0016] The carboxylic acid component is not particularly limited, and a wide range of ordinary aromatic dicarboxylic acids are used, but for example, terephthalic acid or naphthalenedicarboxylic acid are preferred. Among the isomers of naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid is preferred. Polyester elastomer resin (A) in which terephthalic acid is the aromatic carboxylic acid component in the hard segment is excellent in that it easily exhibits high crystallinity, mechanical strength, heat resistance, and chemical resistance due to the symmetry and intermolecular forces of the benzene ring. Furthermore, naphthalenedicarboxylic acid has a structure in which the benzene ring in terephthalic acid is replaced with a naphthalene ring. Due to the high aromaticity and high planarity of this naphthalene ring structure, polyester elastomer resins in which naphthalenedicarboxylic acid is the aromatic carboxylic acid component in the hard segment have higher hydrophobicity and gas barrier properties compared to polyester elastomer resins in which terephthalic acid is the aromatic carboxylic acid component in the hard segment, and as a result are superior in terms of heat aging resistance and hydrolysis resistance. On the other hand, the rigidity and asymmetry of the naphthalene ring structure induce an increase in the elastic modulus and glass transition temperature. Therefore, in terms of flexibility and low-temperature properties of polyester elastomer resin compositions, polyester elastomer resins using terephthalic acid as the aromatic carboxylic acid component in the hard segment are superior to polyester elastomer resins using naphthalenedicarboxylic acid as the aromatic carboxylic acid component in the hard segment.

[0017] In this disclosure, the aromatic dicarboxylic acid is mainly used as a component of the polyester, but other carboxylic acids may be used as long as they do not impair the properties of the resin composition according to this disclosure.

[0018] The content of terephthalic acid or naphthalenedicarboxylic acid relative to 100 mol% of the total carboxylic acid components, including the aromatic dicarboxylic acid constituting the polyester, is preferably 70 mol% or more, more preferably 80 mol% or more, preferably 100 mol% or less, more preferably 98 mol% or less, and even more preferably 95 mol% or less.

[0019] Other carboxylic acid components containing aromatic dicarboxylic acids that constitute the polyester include, in addition to the terephthalic acid and naphthalenedicarboxylic acid mentioned above, aromatic dicarboxylic acids such as diphenyldicarboxylic acid, isophthalic acid, and 5-sodium sulfisoisophthalic acid; cyclic aliphatic dicarboxylic acids such as cyclohexanedicarboxylic acid and tetrahydrophthalic anhydride; and chain-like aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, and hydrogenated dimer acid. These may be used individually or in combination of two or more.

[0020] The hard segment and / or soft segment of the polyester elastomer resin (A) according to this disclosure preferably have a branched skeleton. The branched skeleton may be covalently bonded to the ends of the hard segment and / or soft segment, but it is preferable that it be covalently bonded to the interior of the hard segment and / or soft segment other than the ends.

[0021] The carboxylic acid component constituting the polyester may include a trifunctional or higher polycarboxylic acid, which contains an aromatic dicarboxylic acid. By using such a trifunctional or higher polycarboxylic acid, it becomes possible to introduce a branched skeleton into the hard segment component. Examples of trifunctional or higher polycarboxylic acid components include trimellitic acid, pyromellitic acid, and benzophenonetetracarboxylic acid. By having a trifunctional or higher polycarboxylic acid component, the crosslinking density increases when ester bond rearrangement and recombination occur during heat treatment, thereby increasing the NMP insoluble content and improving hot rigidity and heat aging resistance. The number of carboxyl groups in the polycarboxylic acid is preferably 8 or less, more preferably 6 or less, and even more preferably 4 or less.

[0022] The content of the trifunctional or higher polycarboxylic acid component relative to 100 mol% of the total carboxylic acid component, including the aromatic dicarboxylic acid constituting the polyester, is preferably 0.5 to 2.0 mol%. If the content is 0.5 mol% or more, it can be said that a branched skeleton can be sufficiently introduced into the hard segment skeleton, and if it is 2.0 mol% or less, gelation during the polymerization reaction can be more reliably suppressed. The content is more preferably 0.7 mol% or more, even more preferably 0.9 mol% or more, even more preferably 1.7 mol% or less, and even more preferably 1.5 mol% or less.

[0023] It is preferable that the carboxylic acid component constituting the polyester includes an aromatic dicarboxylic acid, with an unsaturated dicarboxylic acid as a constituent unit. The presence of an unsaturated dicarboxylic acid improves curability by generating intermolecular carbon-carbon bonds through reactions such as the cleavage of unsaturated bonds during heat treatment. Examples of the unsaturated dicarboxylic acid include fumaric acid, maleic acid, itaconic acid, citraconic acid, 2,5-norbornanedicarboxylic acid, tetrahydrophthalic acid, and their acid anhydrides, and one or more of these can be used.

[0024] The content of unsaturated dicarboxylic acid components relative to 100 mol% of the total carboxylic acid components, including aromatic dicarboxylic acids, constituting the polyester is preferably 1 mol% or more, more preferably 2 mol% or more, more preferably 3 mol% or more or 5 mol% or more, and also preferably 20 mol% or less, more preferably 15 mol% or less, and more preferably 10 mol% or less. If the amount of unsaturated dicarboxylic acid falls within the above range, gelation during polymerization can be more reliably suppressed.

[0025] Furthermore, while the alcohol component is not particularly limited, and is generally an aliphatic diol, it can be a linear aliphatic diol or a cyclic aliphatic diol, and is preferably an alkylene glycol having 2 to 8 carbon atoms. Specific examples of linear aliphatic diols with 2 to 8 carbon atoms include ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, cis-butene-1,4-diol, and trans-butene-1,4-diol. These may be used individually or in combination of two or more. Among these, 1,4-butanediol is particularly preferred for imparting heat aging resistance and crystallinity during molding. Examples of cyclic aliphatic diols include cyclohexane-1,2-diol, cyclohexane-1,3-diol, cyclohexane-1,4-diol, cyclohexane-1,2-dimethanol, cyclohexane-1,3-dimethanol, cyclohexane-1,4-dimethanol, tricyclodecanedimethanol, 3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4,8,10-tetraoxaspiro[5.5]undecane, 2,2-bis(4-hydroxycyclohexyl)propane, tetrahydro-2,5-frangimethanol, and 1,4:3,6-dianhydrohexitol. Isomannides, isoidides, and isosorbides, which are cyclic aliphatic diols derived from biomass, can also be used.

[0026] The alcohol component containing the aliphatic diol that constitutes the polyester may include a trifunctional or higher aliphatic polyol. Examples of trifunctional or higher aliphatic polyols include glycerin, trimethylolethane, trimethylolpropane, mannitol, sorbitol, pentaerythritol, and α-methylglucoside. By using such a trifunctional or higher aliphatic polyol, it becomes possible to introduce a branched skeleton into the hard segment component. Having a trifunctional or higher aliphatic polyol component increases the crosslink density when ester bond rearrangement and recombination occur during heat treatment, thereby increasing the NMP insoluble content and improving hot rigidity and heat aging resistance. The number of hydroxyl groups in the aliphatic polyol is preferably 8 or less, more preferably 6 or less, and even more preferably 4 or less.

[0027] The content of trifunctional or higher aliphatic polyol components relative to 100 mol% of the total alcohol components, including the aliphatic diol constituting the polyester, can be 0 to 2.0 mol%. If the content is 2.0 mol% or less, gelation during the polymerization reaction can be more reliably suppressed. The content is preferably 0.5 mol% or more, more preferably 0.7 mol% or more, even more preferably 0.9 mol% or more, and even more preferably 1.7 mol% or less, and even more preferably 1.5 mol% or less.

[0028] As constituent components of the polyester, butylene terephthalate units and butylene naphthalate units are preferred from the viewpoint of physical properties, moldability, and cost performance. Butylene terephthalate units are units consisting of an ester of terephthalic acid and 1,4-butanediol, and butylene naphthalate units are units consisting of an ester of 2,6-naphthalenedicarboxylic acid and 1,4-butanediol.

[0029] Furthermore, when an aromatic polyester suitable as the polyester constituting the hard segment in the polyester elastomer resin (A) is manufactured in advance and then miscibled and copolymerized with the soft segment component, the aromatic polyester can be easily obtained according to known polyester manufacturing methods. The number average molecular weight (Mn) of the aromatic polyester is preferably 10,000 or more, more preferably 20,000 or more, more preferably 40,000 or less, and more preferably 35,000 or less, from the viewpoint of balancing the molecular weight of the final polyester elastomer resin (A) and the time required for miscibled with the soft segment.

[0030] (2) Soft Segments The soft segments constituting the polyester elastomer resin (A) are one or more selected from aliphatic polyether, aliphatic polyester, dimergol, and aliphatic polycarbonate. Aliphatic polycarbonate is preferred from the viewpoint of hot rigidity after heat treatment and heat aging resistance, due to its excellent heat aging resistance and oil swelling resistance.

[0031] Examples of aliphatic polyethers include poly(ethylene oxide) glycol, poly(propylene oxide) glycol, poly(tetramethylene oxide) glycol, poly(hexamethylene oxide) glycol, poly(trimethylene oxide) glycol, copolymers of ethylene oxide and propylene oxide, ethylene oxide adducts of poly(propylene oxide) glycol, and copolymers of ethylene oxide and tetrahydrofuran. From the viewpoint of the elastic properties of the resulting polyester elastomer (A), poly(tetramethylene oxide) glycol and ethylene oxide adducts of poly(propylene oxide) glycol are preferred, and poly(tetramethylene oxide) glycol is more preferred.

[0032] Examples of aliphatic polyesters include poly(ε-caprolactone), polyenanthractone, polycapryloractone, and polybutylene adipate. From the viewpoint of the elastic properties of the resulting polyester elastomer (A), poly(ε-caprolactone) and polybutylene adipate are preferred.

[0033] Dimerols are polyols obtained by reducing dimer acids, which are produced by dimerization reactions such as the Diels-Alder reaction, using natural fatty acids such as soybean oil fatty acids, tall oil fatty acids, and rapeseed oil fatty acids, as well as purified unsaturated fatty acids with approximately 18 to 22 carbon atoms, such as oleic acid, linoleic acid, linolenic acid, and erucic acid, as raw materials.

[0034] The aliphatic polycarbonate, also called a polycarbonate diol, may contain an ester group (-C(=O)-O-) in addition to a carbonate group (-O-C(=O)-O-), and is not particularly limited, but preferably mainly contains an aliphatic diol residue having 2 to 12 carbon atoms. Examples of aliphatic diols constituting the aliphatic diol residue include ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 2,2-dimethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 1,9-nonanediol, and 2-methyl-1,8-octanediol. These may be used individually or in combination of two or more. In particular, from the viewpoint of the flexibility and low-temperature properties of the resulting polyester elastomer resin composition, it is preferable to use an aliphatic diol having 5 to 12 carbon atoms.

[0035] From the viewpoint of low-temperature properties, aliphatic polycarbonates with a low melting point (e.g., 70°C or lower) and a low glass transition temperature are preferred. Generally, aliphatic polycarbonates (including aliphatic polycarbonate diols) used to constitute the soft segments of polyester elastomers include aliphatic polycarbonates containing 1,6-hexanediol as a component. Such aliphatic polycarbonates have a low glass transition temperature of around -60°C and a low melting point of around 50°C, resulting in good low-temperature properties. In addition, aliphatic polycarbonates copolymerized with an appropriate amount of 3-methyl-1,5-pentanediol have a slightly higher glass transition temperature compared to the aliphatic polycarbonate before copolymerization, but their melting point is lower or they become amorphous, resulting in good low-temperature properties. Furthermore, aliphatic polycarbonates containing 1,9-nonanediol and 2-methyl-1,8-octanediol as constituent components have a sufficiently low glass transition temperature of around -70°C and a low melting point of around 30°C, thus corresponding to aliphatic polycarbonates with good low-temperature properties.

[0036] The number average molecular weight of the aliphatic polycarbonate is preferably 5,000 to 80,000. If the number average molecular weight is 5,000 or more, the mechanical properties such as elongation of the resulting polyester elastomer resin (A) can be more reliably ensured. On the other hand, if the number average molecular weight is 80,000 or less, the compatibility between the hard segment and the soft segment is high, so the mechanical properties such as elongation of the resulting polyester elastomer resin (A) can be more reliably ensured. The number average molecular weight is more preferably 7,000 or more, even more preferably 8,000 or more, even more preferably 70,000 or less, and even more preferably 60,000 or less.

[0037] In this disclosure, while the aliphatic polycarbonate can be suitably used as a component of the soft segment, other diols and dicarboxylic acids can be used as long as they do not impair the properties of the resin composition according to this disclosure. In this disclosure, when the soft segment includes not only a polyester portion but also a polycarbonate portion, the carboxylic acid component includes dicarboxylic acids and polycarboxylic acids that form ester bonds in the polyester portion, as well as carbonate esters that form carbonate bonds in the polycarbonate portion. Furthermore, when the soft segment includes not only a polyester portion but also a polyether portion, the alcohol component includes diols and polyols that form ester bonds in the polyester portion, as well as diols and polyols that form ether bonds in the polyether portion.

[0038] The soft segment component may have a branched skeleton. Examples of soft segment components having a branched skeleton include aliphatic polyesters in which some or all of the acid components are trifunctional or higher polycarboxylic acids. Examples of trifunctional or higher polycarboxylic acids include aliphatic polycarboxylic acids such as 1,2,3-propanetricarboxylic acid, 3-methylbutane-1,2,3-tricarboxylic acid, aconitic acid, and citric acid; and aromatic polycarboxylic acids such as trimellitic acid, pyromellitic acid, and benzophenonetetracarboxylic acid, with trifunctional or higher aliphatic polycarboxylic acids being preferred. Having a trifunctional or higher polycarboxylic acid component increases the crosslink density when ester bond rearrangement and recombination occur during heat treatment, thereby increasing the NMP insoluble content and improving hot rigidity and heat aging resistance. The number of carboxyl groups in the polycarboxylic acid is preferably 5 or less.

[0039] The content of the trifunctional or higher polycarboxylic acid component relative to 100 mol% of all carboxylic acid components constituting the aliphatic polyester can be 0 to 2.0 mol%. The content is preferably 0.5 mol% or more, more preferably 0.7 mol% or more, still more preferably 0.9 mol% or more, and is preferably 2.0 mol% or less, more preferably 1.7 mol% or less, still more preferably 1.5 mol% or less. When the content of the trifunctional or higher polycarboxylic acid component falls within the above range, gelation during polymerization can be more reliably suppressed.

[0040] As the alcohol component of the polyester containing a trifunctional or higher polycarboxylic acid as a constituent component, the aliphatic diol residue having 2 to 12 carbon atoms is preferred.

[0041] The soft segment may contain an unsaturated dicarboxylic acid as a constituent unit. By having an unsaturated dicarboxylic acid, curability can be improved through a reaction that forms intermolecular carbon-carbon bonds via cleavage of unsaturated bonds during heat treatment. Examples of the unsaturated dicarboxylic acid include fumaric acid, maleic acid, itaconic acid, citraconic acid, 2,5-norbornanedicarboxylic acid, tetrahydrophthalic acid, and acid anhydrides thereof, and one or two or more of these may be used.

[0042] The content of the unsaturated dicarboxylic acid relative to 100 mol% of all carboxylic acid components in the soft segment can be 0 to 20 mol%. The content is preferably 1 mol% or more, more preferably 2 mol% or more, still more preferably 3 mol% or more or 5 mol% or more, and is preferably 15 mol% or less, more preferably 10 mol% or less, still more preferably 8 mol% or less or 5 mol% or less. When the content of the unsaturated dicarboxylic acid falls within the above range, gelation during polymerization can be more reliably suppressed.

[0043] (3) Elastomer The polyester resin (A) according to the present disclosure is an elastomer. Elastomer is a general term for substances that exhibit elasticity at normal temperature, and refers to polymers that exhibit a small Young's modulus and a large fracture strain.

[0044] The polyester elastomer resin (A) is preferably a copolymer with a melting point of 100 to 230°C. More preferably, the melting point is 130°C or higher, even more preferably 140°C or higher, even more preferably 225°C or lower, and even more preferably 215°C or lower. The carboxylic acid component constituting such a polyester elastomer resin (A) preferably contains 70 mol% or more of terephthalic acid as the aromatic dicarboxylic acid, based on 100 mol% of the total carboxylic acid component. Furthermore, the alcohol component constituting the polyester elastomer resin (A) preferably contains 70 mol% or more of the total aliphatic diol, consisting of one or more selected from the aliphatic polyether, aliphatic polyester, dimer diol, and aliphatic polycarbonate, and 1,4-butanediol, based on 100 mol% of the total alcohol component.

[0045] The content of the trifunctional or higher polycarboxylic acid component relative to 100 mol% of the total carboxylic acid component constituting the polyester elastomer resin (A) can be 0 to 2.0 mol%. Preferably, the content is 0.5 mol% or more, more preferably 0.7 mol% or more, even more preferably 0.9 mol% or more, and also preferably 2.0 mol% or less, more preferably 1.7 mol% or less, and even more preferably 1.5 mol% or less. If the amount of the trifunctional or higher polycarboxylic acid component is within the above range, gelation during polymerization can be more reliably suppressed.

[0046] The content of the trifunctional or higher polyol component relative to 100 mol% of the total alcohol component, including the aliphatic diol, that constitutes the polyester elastomer resin (A) can be 0 to 2.0 mol%. Preferably, the content is 0.5 mol% or more, more preferably 0.7 mol% or more, even more preferably 0.9 mol% or more, and preferably 2.0 mol% or less, more preferably 1.7 mol% or less, and even more preferably 1.5 mol% or less. If the trifunctional or higher polyol component is within the above range, gelation during polymerization can be more reliably suppressed.

[0047] The content of unsaturated dicarboxylic acid relative to 100 mol% of the total carboxylic acid components constituting the polyester elastomer resin (A) can be 0 to 20.0 mol%. Using unsaturated dicarboxylic acid allows for more sufficient curing during heat treatment, ensuring satisfactory hot rigidity and heat aging resistance. On the other hand, if the content of unsaturated dicarboxylic acid is 20.0 mol% or less, gelation during the manufacturing and molding processes of the polyester elastomer resin can be suppressed. The content is preferably 5.0 mol% or more, more preferably 6.0 mol% or more, even more preferably 7.0 mol% or more, and also preferably 20.0 mol% or less, more preferably 15.0 mol% or less, and even more preferably 10.0 mol% or less.

[0048] The mass ratio of hard segments to soft segments constituting the polyester elastomer resin (A) is preferably 20:80 to 85:15, more preferably 25:75 to 80:20, even more preferably 30:70 to 75:25, particularly preferably 30:70 to 65:35, and most preferably 30:70 to 60:40. When the proportion of soft segments is high, i.e., the proportion of hard segments is low, the flexibility of the resulting polyester elastomer resin composition and the elongation at break after heat aging treatment can be maintained, but on the other hand, there is a risk that swelling during oil resistance testing will be increased. Also, when the proportion of soft segments is low, i.e., the proportion of hard segments is high, swelling during oil resistance testing can be reduced, but on the other hand, there is a risk that the flexibility of the resulting polyester elastomer resin composition and the elongation at break after heat aging treatment cannot be maintained.

[0049] The polyester elastomer resin (A) is characterized by the bonding of hard segments and soft segments. Here, it is preferable that the "bonding" is not achieved by chain extenders such as isocyanate compounds, but rather by direct bonding through ester bonds or carbonate bonds contained in the units constituting the hard segments and soft segments. In this case, the total amount of hard segments and soft segments, excluding unavoidable impurities and contaminants, is 100% by mass. For example, as a method for synthesizing the polyester elastomer resin (A) by bonding the hard segments and soft segments, it is preferable to obtain the resin by repeatedly performing transesterification and depolymerization reactions for a certain period of time under molten conditions on the polyester constituting the hard segments and the aliphatic polycarbonate constituting the soft segments. The higher the bond energy between the units constituting the hard segment and the soft segment, the better the heat resistance of the polyester elastomer resin (A). Therefore, by directly bonding through ester bonds and carbonate bonds contained in the units constituting the hard segment and soft segment, rather than using isocyanate compounds, a polyester elastomer resin composition with better heat aging resistance can be obtained.

[0050] In the polyester elastomer resin (A), examples of chain extenders for bonding hard segments and soft segments include diisocyanate compounds for forming urethane bonds (-NH-CO-O-); isocyanate compounds and amine compounds for forming urea bonds (-NH-CO-NH-); diphenyl carbonate and dimethyl carbonate for forming carbonate bonds (-O-CO-O-); diepoxy compounds and dihalogen compounds for forming ether bonds (-O-); diamines for forming amide bonds (-CO-NH-); and isocyanate compounds and thiol compounds for forming thiourethane bonds (-NH-CO-S-). When hard segments and soft segments are bonded with a chain extender, the total ratio of hard segments to soft segments in the polyester elastomer resin (A) is preferably 90% by mass or more, more preferably 95% by mass or more, and even more preferably 98% by mass or more.

[0051] The reduced viscosity of the polyester elastomer resin (A) is preferably 0.6 to 2.0 dl / g. If the reduced viscosity is 0.6 dl / g or higher, the molecular weight of the polymer constituting the polyester elastomer resin (A) is sufficiently large, and tensile properties and heat aging resistance can be more reliably ensured. On the other hand, if the reduced viscosity is 2.0 dl / g or lower, excessive load is not placed on the machine during melt molding, and if the molding method is extrusion molding, surface defects such as melt fractures can be more reliably suppressed. The reduced viscosity is more preferably 0.7 dl / g or higher, and more preferably 1.8 dl / g or lower.

[0052] The acid value of the polyester elastomer resin (A) is preferably 20 to 200 eq / ton. If the acid value is 20 eq / ton or higher, there are enough carboxyl groups that serve as crosslinking points, so curability can be more reliably ensured. Also, when heated to 240°C, the curing reaction proceeds more favorably than the thermal decomposition reaction, and curability is more reliably improved. Furthermore, aqueous dispersion becomes easier. On the other hand, if the acid value is 200 eq / ton or lower, there are fewer carboxyl ends that promote hydrolysis after heat treatment, so hydrolysis resistance is more reliably improved. The acid value is more preferably 50 eq / ton or higher, even more preferably 80 eq / ton or higher, even more preferably 180 eq / ton or lower, and even more preferably 150 eq / ton or lower.

[0053] The acid value of the polyester elastomer resin (A) according to this disclosure can be adjusted by any method. A preferred method for adjusting the acid value is, for example, to add a polycarboxylic acid anhydride after synthesizing the polyester elastomer resin (A).

[0054] Among the compounds having polycarboxylic acid anhydride groups in the molecule for adjusting the acid value of the polyester elastomer resin (A) according to this disclosure, examples of monoanhydrides include monoanhydrides such as phthalic anhydride, succinic anhydride, maleic anhydride, trimellitic anhydride, itaconic anhydride, citraconic anhydride, and monoanhydrides such as 5-(2,5-dioxotetrahydrofurfuryl)-3-cyclohexen-1,2-dicarboxylic acid anhydride; hexahydrophthalic anhydride, tetrahydrophthalic anhydride, etc., and one or more of these can be selected and used. Among these, trimellitic anhydride is preferred in terms of versatility and economic efficiency.

[0055] Among the compounds having polycarboxylic acid anhydride groups in the molecule for adjusting the acid value of the polyester elastomer resin (A) according to this disclosure, the carboxylic acid polyanhydrides include, for example, pyromelitic anhydride, 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-pentanetetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,2,5 Examples include 6-naphthalenetetracarboxylic dianhydride, ethylene glycol bistrimellitate dianhydride, 2,2',3,3'-diphenyltetracarboxylic dianhydride, thiophene-2,3,4,5-tetracarboxylic dianhydride, ethylenetetracarboxylic dianhydride, 4,4'-oxydiphthalic acid dianhydride, and 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, from which one or more can be selected and used. Among these, ethylene glycol bistrimellitate dianhydride is preferred.

[0056] The compounds having polycarboxylic acid anhydride groups within the molecule for imparting the aforementioned acid value can be used individually or in combination with carboxylic acid monoanhydrides and carboxylic acid polyanhydrides.

[0057] The glass transition temperature (Tg) of the polyester elastomer resin (A) is preferably -50 to 20°C from the viewpoint of exhibiting flexibility and low-temperature properties. If the glass transition temperature is -50°C or higher, the mechanical strength is sufficiently satisfied. On the other hand, if the glass transition temperature is 20°C or lower, the toughness and flexibility are sufficiently satisfied. The glass transition temperature is more preferably -45°C or higher, even more preferably -30°C or higher, even more preferably 12°C or lower, and even more preferably 8°C or lower.

[0058] The Shore D hardness of the polyester elastomer resin (A), measured in accordance with JIS K6253:2012, is not particularly limited, but is preferably between 25 and 65. If the Shore D hardness is 65 or less, flexibility and elongation at break after heat aging treatment can be more reliably maintained. On the other hand, if the Shore D hardness is 25 or more, swelling during oil resistance testing can be more reliably suppressed. Furthermore, if the Shore D hardness falls within the above range, it is preferable because it is excellent in flexibility, elongation at break after heat aging treatment, and oil swelling resistance. The Shore D hardness is more preferably 30 or more, and more preferably 55 or less.

[0059] The NMP-insoluble content of the polyester elastomer resin (A) is preferably less than 10% by mass, more preferably less than 5% by mass, and even more preferably less than 1% by mass, when heat-treated in the solvent N-methyl-2-pyrrolidone (NMP) at 150°C for 3 hours. The NMP-insoluble content may be 0% by mass. Having the NMP-insoluble content within the above range makes it possible to suppress gelation during the manufacturing of the polyester elastomer resin (A), as well as foreign matter (such as fish eyes) and appearance defects during melt molding.

[0060] (4) Method for producing polyester elastomer resin (A) The polyester elastomer resin (A) can be produced by known methods. For example, (i) a method of transesterifying a lower alcohol diester of a dicarboxylic acid, an excess amount of low molecular weight glycol, and a soft segment component in the presence of a catalyst, and then polycondensing the resulting reaction product; (ii) a method of esterifying a dicarboxylic acid, an excess amount of glycol, and a soft segment component in the presence of a catalyst, and then polycondensing the resulting reaction product; (iii) a method of synthesizing a polyester constituting the hard segment in advance, adding an aliphatic polycarbonate constituting the soft segment to the obtained polyester, and then performing a transesterification reaction to randomize it; (iv) a method of linking the hard segment component and the soft segment component using a chain linker. Any of these methods can be used. As a chain linker, for example, polyfunctional isocyanate compounds such as diphenylmethane diisocyanate and hexamethylene diisocyanate can be used.

[0061] Furthermore, as a specific method for producing the polyester elastomer resin (A), for example, when producing a polyester elastomer resin (A) mainly composed of terephthalic acid, an aromatic dicarboxylic acid used in the synthesis of the polyester constituting the hard segment, 1,4-butanediol, an aliphatic diol, and 1,6-hexanediol, an aliphatic polycarbonate constituting the soft segment, the method described in Japanese Patent Publication No. 4244067 can be used as the production method. The polyester elastomer resin (A) produced by the above method preferably has a melting point difference (Tm1-Tm3) of 0 to 50°C between the melting point (Tm1) obtained in the first measurement and the melting point (Tm3) obtained in the third measurement when the cycle of heating from room temperature to 300°C at a heating rate of 20°C / min, holding at 300°C for 3 minutes, and then cooling down to room temperature at a cooling rate of 100°C / min is repeated three times using a differential scanning calorimeter. The fact that the melting point difference (Tm1-Tm3) is in the range of 0 to 50°C means that transesterification reactions due to thermal history are sufficiently suppressed, and thus it is possible to provide a polyester elastomer resin (A) that can be obtained in which molded articles with small changes in crystallinity and elastic performance over time in heat aging tests are obtained, which is useful.

[0062] 2. Catalyst (B) The resin composition preferably further contains catalyst (B) in addition to the polyester elastomer resin (A). By including catalyst (B), the self-crosslinking properties of the polyester elastomer resin (A) during heat treatment can be promoted, the NMP insoluble content can be increased, and the hot rigidity can be improved. As catalyst (B), one that promotes the esterification reaction is particularly preferred.

[0063] The content of catalyst (B) is preferably 0.01 to 0.5 parts by mass per 100 parts by mass of polyester elastomer resin (A). If the content of catalyst (B) is 0.01 parts by mass or more, the self-crosslinking effect can be obtained more reliably. If the content of catalyst (B) is 0.5 parts by mass or less, the decomposition reaction of polyester elastomer resin (A) is suppressed, and hot rigidity can be obtained more reliably. The content is more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, even more preferably 0.4 parts by mass or less, and even more preferably 0.3 parts by mass or less.

[0064] Examples of catalysts include sulfonic acid catalysts such as sulfuric acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, naphthalenesulfonic acid, dinonylnaphthalenesulfonic acid, dinonylnaphthalenedisulfonic acid, and camphor sulfonic acid; phosphoric acid catalysts such as phosphoric acid; amine-blocked sulfonic acid catalysts or phosphoric acid catalysts; organotin compounds such as dibutyltin dilaurylate; titanium compounds such as tetrabutyl titanate; zinc compounds such as zinc acetate; hafnium compounds such as hafnium chloride / THF complex; and rare earth compounds such as scandium triflate. Only one of these may be used, or two or more may be used in combination. Among these, tetrabutyl titanate, dodecylbenzenesulfonic acid, and ammonium dodecylbenzenesulfonate are preferred in terms of compatibility with polyester elastomer resin (A). Amine blocking refers to neutralizing a portion of the catalyst by adding an amine.

[0065] Ammonium dodecylbenzenesulfonate salts release the ammonium ion upon heating, exhibiting catalytic activity as dodecylbenzenesulfonic acid. On the other hand, ammonium dodecylbenzenesulfonate salts have lower acidity and significantly reduced corrosiveness compared to dodecylbenzenesulfonic acid, and are easier to handle due to their relatively low skin irritation. Examples of ammonium dodecylbenzenesulfonate salts include inorganic ammonium salts (NH4). +Examples of salts include primary ammonium salts such as methylammonium salt, ethylammonium salt, n-propylammonium salt, isopropylammonium salt, n-butylammonium salt, and tert-butylammonium salt; secondary ammonium salts such as dimethylammonium salt, diethylammonium salt, dipropylammonium salt, dibutylammonium salt, and methylethylammonium salt; and tertiary ammonium salts such as trimethylammonium salt, triethylammonium salt, tripropylammonium salt, tributylammonium salt, N,N-dimethylethylammonium salt, and N,N-dimethylbenzylammonium salt.

[0066] In the polyester elastomer resin composition according to this disclosure, catalyst (B) may be included during the polymerization of polyester elastomer resin (A) or added after polymerization. From the viewpoint of avoiding gelation during the polymerization of polyester resin (A), it is preferable to add catalyst (B) after the polymerization of polyester elastomer resin (A).

[0067] 3. Antioxidant The resin composition may contain an antioxidant in addition to the above-mentioned components (A) to (B) from the viewpoint of improving heat aging resistance and retention stability. Examples of the antioxidant include general-purpose antioxidants such as aromatic amines, hindered phenols, phosphorus, and sulfur. These may be used individually or in combination of two or more.

[0068] Examples of the aromatic amine antioxidants include amines such as N,N-diphenylethylenediamine, N,N-diphenylacetamidine, N,N-diphenylfluamidine, N-phenylpiperidine, dibenzylethylenediamine, triethanolamine, phenothiazine, N,N'-di-sec-butyl-p-phenylenediamine, 4,4'-tetramethyl-diaminodiphenylmethane, P,P'-dioctyl-diphenylamine, N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine, phenyl-α-naphthylamine, phenyl-β-naphthylamine, and 4,4'-bis(4-α,α-dimethylbenzyl)diphenylamine, as well as their derivatives. Examples of such derivatives include reaction products of amines and aldehydes, and reaction products of amines and ketones.

[0069] Examples of the hindered phenol antioxidants include 3,5-di-t-butyl-4-hydroxytoluene, n-octadecyl-β-(4'-hydroxy-3',5'-di-t-butylphenyl)propionate, tetrakis[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane, 1,3,5-trimethyl-2,4,6'-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, and calcium(3,5-di-t-butyl-4-hydroxybenzyl-monoethyl-phosphate). ), triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], pentaerythrityl-tetrakis[3-(3,5-di-t-butylanilino)-1,3,5-triazine, 3,9-bis[1,1-dimethyl-2-{β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]2,4,8,10-tetraoxaspiro[5,5]undecane, bis[3,3-bis(4'-hydroxy-3'-t-butylphenyl)butyrate] glycol ester, triphe Nol, 2,2'-ethylidenebis(4,6-di-t-butylphenol), N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine, 2,2'-oxamidebis[ethyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 1,1,3-tris(3',5'-di-t-butyl-4'-hydroxybenzyl)-S-triazine-2,4,6(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) Examples include socianurates, 3,5-di-t-butyl-4-hydroxyhydrocinnamic ahydrotriester with-1,3,5-tris(2-hydroxyethyl)-S-triazine-2,4,6(1H,3H,5H), N,N-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnaamide), and 3,9-bis[2-{3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy}-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane.

[0070] Examples of phosphorus-based antioxidants include phosphoric acid, phosphorous acid, hypophosphorous acid derivatives, phenylphosphonic acid, polyphosphonates, diphosphite compounds, and other phosphorus-containing compounds. Specific examples include mixtures of triaryl phosphites having monononylphenyl and / or dinonylphenyl groups, tris(2,3-di-t-butylphenyl) phosphite, 4,4'-butylidene-bis(3-methyl-6-t-butylphenyl-di-tridecyl) phosphite, 1,1,3-tris(2-methyl-4-di-tridecylphosphite-5-t-butylphenyl)butane, tris(2,4-di-t-butylphenyl) phosphite, bis(2,4-di-t-butylphenyl)pentaerythritol-diphosphite, and tetrakiss Examples include (2,4-di-t-butylphenyl)-4,4'-biphenylene phosphanite, bis(2,6-di-t-butyl-4-methylphenyl)pentaerythritol-diphosphite, tetrakis(2,4-di-t-butylphenyl)4,4'-biphenylenediphosphonite, triphenyl phosphite, diphenyldecyl phosphite, tridecyl phosphite, trioctyl phosphite, toridedecyl phosphite, trioctadecyl phosphite, trinonylphenyl phosphite, toridedecyltrithiophosphite, and the like.

[0071] Examples of sulfur-based antioxidants include sulfur-containing compounds such as thioethers, dithioates, mercaptobenzimidazoles, thiocarbanilides, and thiodipropion esters. Specific examples include dilauryl thiodipropionate, distearyl thiodipropionate, didodecyl thiodipropionate, ditetradecyl thiodipropionate, dioctadecyl thiodipropionate, pentaerythritol tetrakis(3-dodecylthiopropionate), thiobis(N-phenyl-β-naphthylamine), 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, tetramethylthiuram monosulfide, tetramethylthiuram disulfide, nickel dibutyldithiocarbamate, nickel isopropyl xanthate, and trilauryl trithiophosphite. In particular, thioether-based antioxidants having a thioether structure can be suitably used because they receive oxygen from oxidized substances and reduce them.

[0072] The antioxidant content in the resin composition is preferably 0.01 to 3 parts by mass per 100 parts by mass of the polyester elastomer resin (A). If the antioxidant content is 0.01 parts by mass or more, the effect of improving retention stability and heat aging resistance in processes such as melt molding of the resin composition can be obtained more reliably, and if it is 3 parts by mass or less, the crosslinking reaction to the molded article described later proceeds well, and the bleed-out of the antioxidant contained in the molded article is more reliably suppressed. The content is more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, even more preferably 2 parts by mass or less, and even more preferably 1 part by mass or less.

[0073] 4. Polyamide resin The resin composition may contain a polyamide resin from the viewpoint of improving heat aging resistance. The polyamide resin is a polymer compound having amide bonds in its molecular chain, and examples include polyamides obtained from diamines having aliphatic hydrocarbon groups having 2 to 20 carbon atoms or substituted aliphatic hydrocarbon groups thereof, or aromatic hydrocarbon groups having 6 to 16 carbon atoms or substituted aromatic hydrocarbon groups, and dicarboxylic acids having aliphatic hydrocarbon groups having 2 to 20 carbon atoms or substituted aliphatic hydrocarbon groups thereof, or aromatic hydrocarbon groups having 6 to 16 carbon atoms or substituted aromatic hydrocarbon groups; polymers obtained from lactams; polymers obtained from ω-aminocarboxylic acids, etc.

[0074] Examples of the polyamide resin include polymers obtained by the reaction of a carboxylic acid component such as adipic acid, sebacic acid, linoleic acid, or dodecanedionic acid with a diamine component such as ethylenediamine, hexamethylenediamine, or metaxylylenediamine. Other examples include polyamide 4, polyamide 6, polyamide 7, polyamide 8, polyamide 9, polyamide 11, and polyamide 12 obtained from lactams or ω-aminocarboxylic acids; polyamide 66, polyamide 69, polyamide 610, polyamide 611, polyamide 612, polyamide 6T, polyamide 6I, and polyamide MXD6 obtained from diamines and dicarboxylic acids; and copolymers thereof such as polyamide 6 / 66, polyamide 6 / 610, polyamide 6 / 6T, polyamide 6I / 6T, and polyamide 6 / 66 / 12. These may be used individually or in combination of two or more. Of these, polyamide 6 and / or a copolymerized polyamide resin of two or more elements having a melting point close to that of the polyester elastomer resin (A) is preferred because it is less likely to produce unmelted foreign matter during melt molding, and a copolymerized polyamide resin of two or more elements is more preferred.

[0075] The amine value of the polyamide resin is preferably 50 to 2000 eq / ton. More preferably, the amine value is 70 eq / ton or higher, even more preferably 100 eq / ton or higher, particularly preferably 200 eq / ton or higher, more preferably 1000 eq / ton or lower, even more preferably 700 eq / ton or lower, and particularly preferably 550 eq / ton or lower. Having the amine value within the above range is preferable because it greatly improves the heat aging resistance.

[0076] The polyamide resin content in the resin composition is preferably 0.5 to 10 parts by mass per 100 parts by mass of the polyester elastomer resin (A). If the content is 10 parts by mass or less, the oil swelling resistance, chemical resistance, and low water absorption of the polyester elastomer resin (A) can be sufficiently maintained, and if it is 0.5 parts by mass or more, the effect of improving heat aging resistance can be more reliably exhibited. The content is more preferably 1 part by mass or more, even more preferably 1.2 parts by mass or more, even more preferably 7 parts by mass or less, and even more preferably 3 parts by mass or less.

[0077] 5. Weather-resistant stabilizers When the resin composition according to this disclosure requires weather resistance, it is preferable that the resin composition contains a weather-resistant stabilizer such as an ultraviolet absorber and / or a hindered amine compound. Examples of such weather-resistant stabilizers include benzophenone-based, benzotriazole-based, triazole-based, nickel-based, and salicyl-based light stabilizers.

[0078] Specifically, the weather-resistant stabilizers include 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, p-t-butylphenyl salicylate, 2,4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-di-t-amylphenyl)benzotriazole, and 2-[2'-hydroxy- 3',5'-bis(α,α-dimethylbenzylphenyl)benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)-5-chlorobenazotriazosol, 2-(2'-hydroxy-3',5'-di-t-butylphenyl)-5-chlorobenzothiriazole, 2,5-bis-[5'-t-butylbenzoxazolyl-(2)]-thiophene, bis(3,5-di-t-butyl-4-hydroxybenzylphosphate monoethyl ester) nickel salt, 2-E A mixture of 85-90% toxic-5-t-butyl-2'-ethyl oxalic acid bis-anilide and 10-15% 2-ethoxy-5-t-butyl-2'-ethyl-4'-t-butyl oxalic acid bis-anilide, 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, 2-ethoxy-2'-ethyl oxalic acid bis-anilide, 2-[2'-hydrooxy-5'-methyl-3'-(3'',4'' Examples of light stabilizers include ,5'',6''-tetrahydrophthalimidomethyl)phenyl]benzotriazole, bis(5-benzoyl-4-hydroxy-2-methoxyphenyl)methane, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, 2-hydroxy-4-i-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, and phenyl salicylate. These may be used individually or in combination of two or more.

[0079] The proportion of the weather-resistant stabilizer in the resin composition is preferably 0.1 to 5% by mass, based on the mass of the resin composition (100% by mass).

[0080] 6. Flame retardant When the resin composition according to this disclosure requires flame retardancy, it is preferable to include a flame retardant in the resin composition.

[0081] The aforementioned flame retardants can be broadly classified into halogen-based flame retardants and non-halogen-based flame retardants. Halogen-based flame retardants have high flame retardancy but have a high environmental impact, and their use has been restricted in recent years. Non-halogen-based flame retardants have a lower environmental impact compared to halogen-based flame retardants, but their flame retardancy is inferior to halogen-based flame retardants, so the required content is generally higher. In both cases, if the content is excessive, the elongation at cleavage of the resulting molded article tends to decrease, and this tendency becomes more pronounced with the presence of cross-linked structures and heat aging treatment. In other words, halogen-based and non-halogen-based flame retardants have different flame retardancy efficiencies and different optimal content ranges, which will also be explained below.

[0082] (1) Halogenated flame retardants Examples of halogenated flame retardants include brominated flame retardants. Examples of brominated flame retardants include hexabromocyclododecane, decabromodiphenyl oxide, octabromodiphenyl oxide, tetrabromobisphenol A, bis(tribromophenoxy)ethane, bis(pentabromophenoxy)ethane, tetrabromobisphenol A epoxy resin, tetrabromobisphenol A carbonate, ethylene (bistetrabromophthal)imide, ethylenebispentabromodiphenyl, tris(tribromophenoxy)triazine, bis(dibromopropyl)tetrabromobisphenol A, bis(dibro Examples include (mopropyl)tetrabromobisphenol S, brominated polyphenylene ethers (including poly(di)bromophenylene ethers, etc.), brominated polystyrene (including polydibromostyrene, polytribromostyrene, crosslinked brominated polystyrene, etc.), brominated crosslinked aromatic polymers, brominated epoxy resins, brominated phenoxy resins, brominated styrene-maleic anhydride polymers, tetrabromobisphenol S, tris(tribromoneopentyl) phosphate, polybromotrimethylphenylindan, and tris(dibromopropyl)-isocyanurate. These may be used individually or in combination of two or more. Among these, brominated polystyrene is preferred from the viewpoint of compatibility with polyester elastomer resin (A) and exhibiting high heat aging resistance.

[0083] The resin composition may contain a flame retardant additive in combination with the flame retardant, from the viewpoint of a synergistic effect of flame retardancy. In particular, the flame retardant additive is often used in combination with a halogen-based flame retardant. For example, when the halogen-based flame retardant is used as the flame retardant, it is preferable to use an antimony oxide compound in combination with the flame retardant additive. Examples of the antimony oxide compound include antimony trioxide, antimony pentoxide, or sodium antimonate.

[0084] The total content of the combination of the flame retardant and the flame retardant aid is preferably 5 to 40 parts by mass per 100 parts by mass of the polyester elastomer resin (A) when using the halogen-based flame retardant such as the brominated flame retardant and the flame retardant aid such as antimony trioxide. If the total content is 5 parts by mass or more, flame retardancy can be obtained more reliably, and if it is 40 parts by mass or less, the mechanical properties such as elongation at break of the resulting molded article can be sufficiently maintained. By using a total content within the above range, a resin composition with particularly excellent flame retardancy and heat aging resistance can be prepared.

[0085] (2) Non-halogenated flame retardants Examples of non-halogenated flame retardants include nitrogen-based flame retardants, phosphorus-based flame retardants, silicon-based flame retardants, metal hydroxides, and metal borates, and from the viewpoint of flame retardancy, phosphorus-based flame retardants are preferred.

[0086] Examples of phosphorus-based flame retardants used in the present invention include organophosphorus compounds and inorganic phosphorus compounds.

[0087] Examples of the aforementioned organophosphorus compounds include phosphates, phosphonates, phosphinates, and phosphites. More specifically, examples include trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, tributoxyethyl phosphate, octyldiphenyl phosphate, tricresyl phosphate, cresyldiphenyl phosphate, triphenyl phosphate, trixylenyl phosphate, tris-isopropylphenyl phosphate, diethyl-N,N-bis(2-hydroxyethyl)aminomethylphosphonate, and bis(1,3-phenylenediphenyl) phosphate. These may be used individually or in combination of two or more. Among these, metal phosphinate salts are preferred from the viewpoint of flame retardancy, and aluminum phosphinate salts are more preferred.

[0088] Examples of the inorganic phosphorus compounds include red phosphorus compounds and inorganic phosphate compounds such as (poly)ammonium phosphate, (poly)melamine phosphate, and (poly)piperazine phosphate. In some industries, there are restrictions on the use of organophosphorus compounds, so the application of inorganic phosphorus compounds may be necessary. In this case, (poly)phosphate compounds are preferred as the inorganic phosphorus compounds.

[0089] Examples of the (poly)phosphate compounds include monomeric orthophosphates and condensed phosphates obtained by a dehydration reaction of orthophosphates, with pyrophosphates, metaphosphates, and polyphosphates being examples of condensed phosphates. The (poly)phosphate compound refers to one or more compounds selected from orthophosphate compounds, pyrophosphate compounds, metaphosphate compounds, and polyphosphate compounds. While there are no particular problems with using any of these (poly)phosphate compounds, a (poly)phosphate compound with a lower molecular weight is preferred from the viewpoint of exhibiting high flame retardancy. Furthermore, a (poly)phosphate compound with a higher molecular weight is preferred from the viewpoint of suppressing bleed-out of phosphorus-based flame retardants and elution during immersion in water. Therefore, among the (poly)phosphate compounds, pyrophosphate compounds are preferred. The (poly)phosphate compound may be a single (poly)phosphate compound or a composite flame retardant containing two or more (poly)phosphate compounds.

[0090] The properties (flame retardancy and thermal stability) of the (poly)phosphate compounds are derived from the chemical structure of their counterions, and each counterion has its own unique characteristics. For example, ammonium (poly)phosphate has excellent flame retardancy but poor processing stability, while melamine (poly)phosphate has excellent processing stability but poor flame retardancy. By using a composite flame retardant containing two or more of the (poly)phosphate compounds, a composition with an excellent balance of multiple properties such as flame retardancy and processing stability can be obtained. In particular, using a composite flame retardant consisting of melamine (poly)phosphate and piperazine (poly)phosphate as the phosphorus-based flame retardant is a preferred embodiment because it allows for a composition with an even better balance of flame retardancy and processing stability (i.e., mechanical properties). Furthermore, using a composite flame retardant consisting of melamine pyrophosphate and piperazine pyrophosphate as the phosphorus-based flame retardant is an even more preferred embodiment from the viewpoint of heat aging resistance.

[0091] The phosphorus-based flame retardant is preferably one that has an average particle size D50 of 20 μm or less and a phosphorus concentration of 15% by mass or more. The upper limit of the average particle size D50 is more preferably 16 μm or less, and even more preferably 12 μm or less. There is no particular limit to the lower limit of the average particle size D50, but it is preferably 0.1 μm or more. If a flame retardant with a large average particle size D50 is used, there is a risk that the surface smoothness of the resulting molded article (extruded article, etc.) will deteriorate and the heat aging resistance will decrease during extrusion molding, etc. The lower limit of the phosphorus concentration is preferably 18% by mass or more, and more preferably 20% by mass or more. There is no particular limit to the upper limit of the phosphorus concentration, but it is preferably 30% by mass or less. If a flame retardant with a low phosphorus concentration is used, there is a risk that the flame retardant effect will be poor, requiring the addition of a large amount, making it difficult to achieve both flame retardancy and other properties.

[0092] The average particle size D50 can be measured and analyzed using a laser diffraction particle size distribution analyzer, and the phosphorus concentration can be measured (calculated) using ICP emission spectroscopy.

[0093] The content of the non-halogenated flame retardant, particularly the phosphorus-based flame retardant, in the resin composition is preferably 5 to 50 parts by mass per 100 parts by mass of the polyester elastomer resin (A). If the content of the phosphorus-based flame retardant is 5 parts by mass or more, sufficient flame retardancy can be obtained, and if it is 50 parts by mass or less, sufficient mechanical properties such as elongation at break can be ensured. The content is more preferably 8 parts by mass or more, even more preferably 10 parts by mass or more, particularly preferably 15 parts by mass or more, more preferably 45 parts by mass or less, even more preferably 40 parts by mass or less, and particularly preferably 35 parts by mass or less. By using a phosphorus-based flame retardant in a content within the above range, a resin composition with particularly excellent flame retardancy and heat aging resistance can be obtained.

[0094] Furthermore, the resin composition may optionally contain a non-halogenated flame retardant other than the phosphorus-based flame retardant.

[0095] 7. Other Additives The resin composition may contain other resins, coloring pigments, inorganic fillers, organic fillers, coupling agents, tack enhancers, quenchers, metal deactivators, and other stabilizers, to the extent that they do not impair the properties of the resin composition relating to this disclosure.

[0096] 8. Crosslinkable polyester elastomer resin composition (1) Properties When the crosslinkable polyester elastomer resin composition according to this disclosure is heated at a relatively high temperature for a relatively long time or irradiated with an electron beam, a high degree of crosslinking is formed and the curability is improved.

[0097] The elongation at break of the resin composition after heat treatment is preferably 200% or more, more preferably 300% or more, and even more preferably 400% or more, from the viewpoint of exhibiting flexibility in the molded article. There is no particular upper limit to the elongation at break, but it can be, for example, 1000%.

[0098] When the crosslinkable polyester elastomer resin composition according to this disclosure is heat-treated in N-methyl-2-pyrrolidone (NMP) as a solvent at 150°C for 3 hours, the NMP insoluble content is preferably less than 10% by mass, more preferably less than 5% by mass, and even more preferably less than 1% by mass. The NMP insoluble content may be 0% by mass. Having the NMP insoluble content within the above range suppresses gelation during the manufacturing of the polyester elastomer resin (A), and prevents foreign matter (such as fish eyes) and appearance defects during melt molding.

[0099] On the other hand, after heat-treating the crosslinkable polyester elastomer resin composition according to this disclosure at 240°C for 1 hour, and then heat-treating it in N-methyl-2-pyrrolidone (NMP) at 150°C for 3 hours, the insoluble content (NMP insoluble content) is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, and particularly preferably 40% by mass or more. The NMP insoluble content is an indicator of the amount of crosslinking formed, and by setting the NMP insoluble content after heat-treating at 240°C for 1 hour to be above the above range, it becomes possible to maintain its rigidity even in a temperature environment above the melting point where the polyester elastomer resin (A) would normally melt and soften, which is useful. The upper limit of the amount of NMP insoluble content may be 100% by mass, but since complete crosslinking may be difficult, 90% by mass is preferred, 80% by mass is more preferred, and 70% by mass is even more preferred.

[0100] The melt flow rate (MFR) of the resin composition can be measured at 230°C and under a load of 2.16 kg in accordance with the flow test method for thermoplastic plastics specified in JIS K7210. The MFR value is not particularly limited, but varies depending on the manufacturing method of the molded article. For example, in extrusion molding, the MFR at the molding temperature is preferably 1 to 200 g / 10 min, in injection molding, it is preferably 5 to 200 g / 10 min, and in blow molding, it is preferably 0.1 to 5 g / 10 min. If the MFR value is within the above range, it becomes possible to more reliably mold the resin composition into the desired molded article. In extrusion molding, the MFR is more preferably 2 g / 10 min or more, and more preferably 100 g / 10 min or less. In injection molding, the MFR is more preferably 10 g / 10 min or more, and more preferably 100 g / 10 min or less. In blow molding, the MFR is more preferably 0.2 g / 10 min or more, and more preferably 3 g / 10 min or less.

[0101] (2) Method for manufacturing the resin composition The method for manufacturing the resin composition according to this disclosure is not particularly limited, but can be manufactured by melting and kneading each component using a known single-screw extruder, twin-screw extruder, kneader, Banbury mixer, roll, etc. Among these, it is preferable to use a twin-screw extruder from the viewpoint of kneadability, continuous productivity, and self-cleaning properties.

[0102] When using the aforementioned twin-screw extruder, it is preferable to appropriately select the extruder barrel temperature and screw configuration to control the shear stress, thermal history, and residence time applied to the polymer, thereby promoting kneading and reaction while suppressing polymer degradation and side reactions.

[0103] The melting temperature of the resin composition during the melt-kneading process is preferably 160 to 280°C. If the melting temperature is 160°C or higher, each component can be sufficiently melted, and unmelted gel can be suppressed. If the melting temperature is 280°C or lower, deterioration of the resin composition and crosslinking within the molding machine can be suppressed more reliably. More preferably, the melting temperature is 170°C or higher, even more preferably 180°C or higher, even more preferably 240°C or lower, and even more preferably 220°C or lower.

[0104] The screw rotation speed during melt kneading is preferably 50 to 500 rpm. If the screw rotation speed is 50 rpm or higher, each component contained in the resin composition can be more reliably and uniformly melted, and if it is 500 rpm or lower, polymer degradation due to shear heat and side reactions can be more reliably suppressed. The screw rotation speed is more preferably 100 rpm or higher, and more preferably 400 rpm or lower.

[0105] Furthermore, the discharge rate during melt-kneading is preferably 5 to 1,000 kg / h. If the discharge rate is 5 kg / h or more, it is possible to more reliably suppress unevenness in kneading and excessive heat retention due to a decrease in the resin filling rate in the extruder, and if it is 1,000 kg / h or less, the residence time in the extruder will not become excessively short, and uniform kneading can be more reliably achieved. The discharge rate is more preferably 10 kg / h or more, and more preferably 500 kg / h or less.

[0106] (3) Method for manufacturing a molded article The method for manufacturing a molded article according to the present disclosure is not particularly limited, but for example, the resin composition obtained by the method for manufacturing the resin composition can be melt-kneaded to obtain a molded article by performing molding processes such as extrusion molding, injection molding, compression molding, and blow molding using a commonly used molding machine. Examples of extrusion molding include extrusion film formation, T-die film formation, and calender film formation. In particular, in the method for manufacturing a molded article, it is preferable to use extrusion molding from the viewpoint of making it easier to apply a continuous crosslinking process in the crosslinking process described later.

[0107] (4) Method for manufacturing a crosslinked molded article The molded article according to this disclosure is hardened by crosslinking the polyester elastomer resin (A) by heating at a relatively high temperature for a relatively long time or by irradiating it with an electron beam. Since the polyester elastomer resin (A) according to this disclosure has a branched skeleton, the formed crosslinked article is highly crosslinked. A crosslinked molded article can be obtained by performing a crosslinking step to crosslink the molded article. The obtained crosslinked molded article can be made into a highly heat-resistant crosslinked molded article that maintains flexibility and mechanical properties as an elastomer material while achieving both hot rigidity in a high-temperature environment and heat aging resistance by a manufacturing method using a molding step and a crosslinking step.

[0108] The shape of the molded article before crosslinking used in the method for manufacturing the crosslinked molded article is not particularly limited, but can be selected according to the molding method, and may be any of the following: a one-dimensional shape such as a linear or rod shape; a two-dimensional shape such as a sheet or film shape; or a three-dimensional shape such as a shape having recesses, protrusions, or uneven surfaces, a tube shape, a hose shape, or a wire coating shape.

[0109] The method for manufacturing a crosslinked molded article according to this disclosure includes a crosslinking step in addition to the molding steps such as extrusion molding. By performing the crosslinking step, it is possible to provide a crosslinked molded article that possesses high heat resistance while maintaining mechanical properties in addition to the flexibility of an elastomer material, making it useful.

[0110] The aforementioned crosslinking process refers to a process of forming a crosslinked structure in the polyester elastomer resin (A), and examples of such crosslinking processes include thermal crosslinking and electron beam crosslinking.

[0111] The aforementioned thermal crosslinking is generally performed by incorporating organic oxides or the like into a polymer material and applying a thermal history under a pressurized environment to form a crosslinked structure.

[0112] The aforementioned electron beam crosslinking is a method in which an electron beam is irradiated onto the polymer constituting the polyester elastomer resin (A), and radicals generated by the energy of the electron beam are used as a starting point to crosslink the polymer molecules with each other.

[0113] The method for manufacturing a crosslinked molded article according to this disclosure preferably includes a step of applying a thermal history as the crosslinking step. As described above, the method involves forming a molded article from the resin composition by extrusion molding or the like, and then applying a thermal history step to produce a crosslinked molded article. By further applying a thermal history to the molded article obtained by the extrusion molding or the like, the molecular chains of the polymer constituting the polyester elastomer resin (A) are crosslinked, making it possible to provide a crosslinked molded article that is not only flexible as an elastomer material but also possesses high heat resistance while maintaining mechanical properties, which is useful.

[0114] The process conditions for imparting the aforementioned thermal history are typically in the range of approximately 180 to 260°C for about 10 minutes to 2 hours. Preferably, the temperature is in the range of approximately 200 to 250°C, and the duration is preferably about 20 minutes to 1 hour.

[0115] The crosslinked molded article may be a crosslinked molded article using only the resin composition, or it may be a composite crosslinked molded article formed by bonding or joining a crosslinked molded article formed with the resin composition and a member formed with a resin composition containing other resins. Furthermore, the composite crosslinked molded article may be directly fused between the members without the use of an adhesive.

[0116] When a molded article made from the resin composition is heat-treated at 240°C for 1 hour, the elongation at break (absolute value) measured in accordance with JIS K6251 is preferably 200% or more, more preferably 250% or more, even more preferably 300% or more, and particularly preferably 350% or more. When the elongation at break satisfies the above range, the resin composition is excellent in flexibility, toughness, and maintenance of elongation at break after heat aging treatment. On the other hand, if the elongation at break is smaller than the above range, the toughness of the crosslinked molded article and the maintenance of elongation at break after heat aging treatment tend to decrease. There is no particular upper limit to the elongation at break, but it can be, for example, 1000%.

[0117] After heat-treating the molded body made of the resin composition at 240°C for 1 hour, the storage modulus E' at 220°C obtained by dynamic viscoelasticity measurement in accordance with JIS K7244 is 1.0 × 10⁻⁶. 4It is preferable that the pressure be Pa or higher, and 1.0 × 10 5 Pa or higher is more preferable, 5.0 × 10 5 Pa or higher is more preferable, and 1.0 × 10 6 A storage modulus of Pa or higher is particularly preferred. Here, the storage modulus E' is a value obtained by dynamic viscoelasticity measurement in accordance with JIS K7244, and can be rephrased as an indicator of stiffness at that temperature. By satisfying the above range for the storage modulus E', a resin composition can be obtained that has excellent hot stiffness in the temperature range above the melting point of the polyester elastomer resin (A), as well as excellent heat aging resistance in the temperature range below the melting point of the polyester elastomer resin (A). Furthermore, if the storage modulus E' is smaller than the above range, it effectively means that there is no hot stiffness at 220°C, and the shape cannot be maintained due to melt softening. There is no particular upper limit to the storage modulus E', but for example, 1.0 × 10 8 It can be set to Pa.

[0118] For the storage modulus E' obtained after heat-treating a molded article made of the resin composition at 240°C for 1 hour to satisfy the above range, for example, the insoluble content (NMP insoluble content) after heat-treating the heat-treated resin composition in N-methyl-2-pyrrolidone (NMP) at 150°C for 3 hours is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, and particularly preferably 40% by mass or more. The NMP insoluble content is an indicator of the amount of crosslinking formed, and by setting the NMP insoluble content to be above the above range, it becomes possible to maintain its rigidity even in a temperature environment above the melting point where the polyester elastomer resin (A) would normally melt and soften, which is useful. The upper limit of the amount of NMP insoluble content may be 100% by mass, but since complete crosslinking may be difficult, 90% by mass is preferred, 80% by mass is more preferred, and 70% by mass is even more preferred.

[0119] The aforementioned resin composition can achieve both hot rigidity in high-temperature environments (e.g., 220°C) and heat aging resistance in high-temperature environments (e.g., particularly 190-200°C) while maintaining flexibility and mechanical properties as an elastomer material. It is preferable that heat aging resistance be achieved at 190°C, and more preferably at 190-200°C.

[0120] This disclosure relates to an extruded article formed from and crosslinked with the aforementioned resin composition. Since the extruded article is formed and crosslinked using the aforementioned resin composition, it is a useful extruded article that is highly heat resistant, achieving both hot rigidity in high-temperature environments and resistance to heat aging while maintaining flexibility and mechanical properties as an elastomer material.

[0121] This disclosure relates to a coating material formed from and crosslinked from the resin composition. Since the coating material is formed and crosslinked using the resin composition, it is a useful coating material that is highly heat resistant, achieving both hot rigidity in high-temperature environments and resistance to heat aging while maintaining the flexibility and mechanical properties of an elastomer material.

[0122] The resin composition described herein can be used in a wide range of applications, such as various components of electrical products, hoses, tubes, and covering materials for cables, and can also be developed into various molded products using molding methods such as injection molding, extrusion molding, transfer molding, and blow molding.

[0123] This application claims the benefit of priority based on Japanese Patent Application No. 2025-50653, No. 2025-50654, No. 2025-50655, No. 2025-50656, and No. 2026-10052, filed on 23 January 2026. The entire contents of the specifications of Japanese Patent Application No. 2025-50653, No. 2025-50654, No. 2025-50655, No. 2025-50656, and No. 2026-10052, filed on March 25, 2025, are incorporated herein by reference.

[0124] Examples are given below to illustrate the effects of the present invention, but the present invention is not limited in any way by these examples.

[0125] Example 1: Production of Polyester Elastomer Resin Composition (1) Production of Polyester Elastomer Resin (A-1) 100 parts by mass of dimethyl terephthalate ("DMT", manufactured by SK Petrochemical), 93.3 parts by mass of 1,4-butanediol ("1,4-BDO", manufactured by Mitsubishi Chemical Corporation), 0.5 parts by mass of trimellitic anhydride ("TMA", manufactured by Shotan Chemical Co., Ltd.), and 0.05 parts by mass of tetrabutyl titanate ("TBT", manufactured by Nacalai Tesque) were charged into a reaction vessel, and a transesterification reaction was carried out by raising the temperature from room temperature to 225°C over 150 minutes. Then, the pressure inside the vessel was gradually reduced and the temperature was further increased, and an initial condensation reaction was carried out over 75 minutes at 245°C and below 0.9 Torr. A polymerization reaction was then carried out at 245°C and below 0.9 Torr for 80 minutes to obtain a polyester resin (number average molecular weight: 30000) that would become a hard segment. 100 parts by mass of aliphatic polycarbonate diol ("Carbonate Diol UH-CARB200," manufactured by Ube Industries, Ltd., number average molecular weight: 2000, 1,6-hexanediol type) and 2.9 parts by mass of fumaric acid ("FA," manufactured by Fuso Chemical Industries, Ltd.) were charged into a separate reaction vessel. The temperature was raised from room temperature to 240°C over 130 minutes to carry out the esterification reaction. Next, 7.5 parts by mass of diphenyl carbonate was added and the reaction was carried out at a temperature of 205°C and 130 Pa. After 2 hours, the contents were cooled to obtain aliphatic polycarbonate (number average molecular weight: 12000) which would become a soft segment. 50 parts by mass of the polyester resin and 50 parts by mass of the aliphatic polycarbonate were stirred for 1 hour at 230-245°C and 130 Pa. After confirming that the contents had become transparent, the mixture was cooled to 220°C under a nitrogen atmosphere. Next, 0.9 parts by mass of TMA were added, and stirring was continued for 30 minutes at 200-230°C under a nitrogen atmosphere. The contents were removed and cooled to obtain polyester elastomer (A-1). The melting point of polyester elastomer (A-1) was 200°C, the glass transition temperature (Tg) was -10°C, the reduced viscosity was 1.00 dl / g, and the acid value was 110 eq / ton.

[0126] (2) Production of the polyester elastomer resin composition According to the composition and content ratio of the resin composition described in Table 3, 100 parts by mass of polyester elastomer resin (A-1) was kneaded and pelletized with catalyst (B) and other additives (C) using a twin-screw extruder, and then dried under reduced pressure at 100°C for 8 hours to obtain the resin composition. The catalyst (B) and other additives (C) used are shown below.

[0127] Catalyst (B): (B-1) Tetrabutyl titanate (TBT, manufactured by Nacalai Tesque) (B-2) Dodecylbenzenesulfonic acid (DDBSA, manufactured by Kanto Chemical Co., Ltd.)

[0128] Other additives (C): (C-1) Nonflex DCD (4,4'-bis(α,α-dimethylbenzyl)diphenylamine, manufactured by Ouchi Shinko Chemical Co., Ltd.) (C-2) Irganox 1010 (hindered phenol antioxidant, manufactured by BASF) (C-3) Polyamide resin (polyamide 6 / 66 / 12) (relative viscosity 1.3, amine value 490 eq / ton)

[0129] Examples 2-16 and Comparative Examples 1-6: Polyester elastomer resins (A-2) to (A-14) and (a-1) to (a-5) were produced in the same manner as in Example 1(1), except that the composition and content ratios were changed as shown in Tables 1 and 2. In Tables 1 and 2, the "mol%" for HS components and SS components indicates the mol% of each acid and each alcohol relative to the total carboxylic acid components and total alcohol components in the hard segment and soft segment, respectively. Next, the polyester elastomer resin compositions of Examples 2-16 and Comparative Examples 1-6 were produced in the same manner as in Example 1(2), except that the composition and content ratios were changed as shown in Tables 3 and 4. The characteristic values ​​of the polyester elastomer resins were measured using Test Examples 1-12, and the polyester elastomer resin compositions were evaluated using Test Examples 6-11. The results are shown in Tables 1-4.

[0130] Test Example 1: Measurement of Resin Composition Samples of polyester resin, aliphatic polycarbonate, and polyester elastomer (A) were dissolved in deuterated chloroform and measured using a nuclear magnetic resonance (NMR) spectrometer ("400-MR" manufactured by VARIAN). 1 ¹H NMR analysis was performed. The molar ratio was determined from the ratio of the integral values.

[0131] Test Example 2: A sample of melting point polyester elastomer resin (5 mg) was placed in an aluminum pan, sealed by pressing down on the lid, and heated at 250°C for 5 minutes to completely melt the sample. After that, it was rapidly cooled with liquid nitrogen. Using a differential scanning calorimetry analyzer ("DSC220" manufactured by Seiko Electronics Industries Co., Ltd.), the sample was heated from -150°C to 250°C at a heating rate of 20°C / min, and the endothermic peak temperature was determined as the melting point (°C) from the obtained thermogram curve.

[0132] Test Example 3: A polyester elastomer resin sample (0.05 g) was dissolved in a mixed solvent of phenol / tetrachloroethane = 60 / 40 (mass ratio) (25 mL), and the reduced viscosity (dl / g) was measured at 30°C using an Ostwald viscometer.

[0133] Test Example 4: Acid Value A polyester elastomer resin sample (200 mg) dried under reduced pressure at 100°C for 8 hours was dissolved in hot benzyl alcohol (10 mL). After cooling the resulting solution, chloroform (10 mL) and phenol red were added, and the acid value (eq / ton) was determined by dissolution titration with a 1 / 25 N methanol solution of KOH.

[0134] Test Example 5: Glass Transition Temperature A polyester elastomer resin sample (5 mg) was placed in an aluminum pan, sealed by pressing down on the lid, and cooled to -150°C using liquid nitrogen. Then, the temperature was increased to 100°C at a heating rate of 20°C / min using a differential scanning calorimetry analyzer ("DSC220" manufactured by Seiko Electronics Industries). In the endothermic curve obtained during this process, the temperature at the intersection of the baseline before the endothermic peak appears and the tangent line toward the endothermic peak was defined as the glass transition temperature (°C).

[0135] Test Example 6: Measurement of Melt Flow Rate (MFR) The melt flow rate (MFR, g / 10 min) of the resin composition was measured at 230°C and 2160 g in accordance with the test method (Method A) described in JIS K7210. A resin composition with a moisture content of 0.1% by mass or less was used as the measurement sample.

[0136] Test Example 7: The tensile elongation at break (%) of the resin composition before heat treatment was measured in reference to JIS K6251:2010. The test specimens were prepared by drying the resin composition under reduced pressure at 100°C for 8 hours, then using a 30φ single-screw extruder to produce a 200 μmt sheet at a cylinder temperature (Tm + 20°C), and punching out a dumbbell-shaped No. 3 test specimen from the sheet.

[0137] Test Example 8: Elongation at Cutting After Heat Treatment The tensile elongation (%) at break of the resin composition after heat treatment was measured in reference to JIS K6251:2010. Test specimens were prepared by extruding a 200 μmt sheet made from a resin composition dried under reduced pressure at 100°C for 8 hours using a 30φ single-screw extruder at a cylinder temperature (Tm + 20°C), heating the sheet in air at 240°C for 1 hour, and then punching out a dumbbell-shaped No. 3 test specimen from the sheet.

[0138] Test Example 9: Measurement of NMP Insoluble Content A 200 μmt sheet (approximately 0.1 g) of a resin composition dried under reduced pressure at 100°C for 8 hours was prepared using a 30φ single-screw extruder at a cylinder temperature (Tm + 20°C). After heating in 240°C air for 1 hour, the sheet was wrapped in a 150-mesh wire mesh and immersed in NMP (60 mL) at 150°C for 3 hours. The sheet was then removed, washed with acetone, and completely dried in a 100°C environment. Let (X) be the mass of the sample before NMP immersion, and (Y) be the mass of the sample after NMP immersion and complete drying. The NMP insoluble content (mass%) was calculated using the following formula: NMP Insoluble Content (mass%) = [(Y) / (X)] × 100 The NMP insoluble content before heat treatment was determined in the same manner as above.

[0139] Test Example 10: Heat aging resistance was evaluated using the dumbbell-shaped No. 3 test specimen obtained in Heat Treatment Test Example 7. The test specimen was heated in an air environment at 200°C for 240 hours, then removed, and the elongation at break (%) was measured in accordance with JIS K6251:2010 as described above.

[0140] Test Example 11: Storage Modulus A resin composition dried under reduced pressure at 100°C for 8 hours was prepared as a 200 μmt sheet using a 30φ single-screw extruder at a cylinder temperature (Tm + 20°C). After heating in 240°C air for 1 hour, the sheet was cut into strips 15 mm long and 4 mm wide to produce a cross-linked molded body. The obtained cross-linked molded body was used as a test specimen, and the dynamic viscoelasticity in tensile mode was measured using a dynamic viscoelasticity measuring device ("Rheogel-E4000," manufactured by UBM Corporation) in accordance with the test standard JIS K7244, under the following conditions to confirm the temperature dependence of the storage modulus E' and evaluate the storage modulus E' (Pa) at 220°C. Measurement temperature range: 23°C to 300°C Heating rate: 4°C / min Measurement frequency: 10 Hz

[0141] Test Example 12: Short-term heat resistance (hot stiffness at 220°C) The dumbbell-shaped No. 3 test specimen obtained in Test Example 7 after heat treatment was placed in a hot air circulating oven set to 220°C for 5 minutes. After removing it from the oven, its appearance was visually inspected and judged according to the following criteria. In the cases of "○" and "◎" below, it was judged to be at a level that does not pose a practical problem. × (bad): The test specimen melted after the test and did not maintain its shape from before the test. ○ (good): The test specimen did not melt after the test and maintained its shape from before the test. ◎ (excellent): The test specimen did not melt after the test and maintained its shape from before the test, and furthermore, no hole was made when a 220°C soldering iron was pressed against the removed test specimen.

[0142]

[0143]

[0144]

[0145]

[0146]

[0147]

[0148] As is clear from the results of Tables 1 to 4, it was confirmed that the resin compositions of Comparative Examples 1 to 6, which do not satisfy the requirements of the present invention, exhibit inferior results in terms of elongation at break after heat aging treatment at 200°C for 240 hours (heat aging resistance) and hot rigidity at 220°C. Specifically, it was confirmed that none of Comparative Examples 1 to 6 produced NMP-insoluble content after heat treatment, they fluidized in an environment of 220°C, and neither heat aging resistance nor hot rigidity at 220°C could be satisfied. In particular, it was confirmed that even in Comparative Example 2, even when a polyester elastomer resin having a high melting point was used, neither 200°C heat aging resistance nor hot rigidity at 220°C could be satisfied.

[0149] In contrast, in Examples 1 to 16 that satisfy the requirements of the present invention, the use of the polyester elastomer resin (A), which exhibits an appropriate melt flow rate, is thermoplastic, and is crosslinked by heat treatment for a predetermined period of time to generate NMP-insoluble content, maintains elongation at break after heat aging treatment at 200°C for 240 hours, and it was confirmed that the compositions have excellent heat aging resistance. Furthermore, the storage modulus at 220°C is 1.0×10 4 Pa or higher, which is above the melting point of the polyester elastomer resin (A) used, it was confirmed that the molded article can maintain its shape even in an environment of 220°C where the shape would originally not be maintainable, and has excellent hot rigidity.

[0150] Example 17: Production of Polyester Elastomer Resin Composition (1) Production of Polyester Elastomer Resin (A-15) 100 parts by mass of dimethyl terephthalate ("DMT", manufactured by SK Petrochemical), 98.4 parts by mass of 1,4-butanediol ("1,4-BDO", manufactured by Mitsubishi Chemical Corporation), 0.5 parts by mass of trimellitic anhydride ("TMA", manufactured by Shotan Chemical Co., Ltd.), 3.2 parts by mass of fumaric acid ("FA", manufactured by Fuso Chemical Industry Co., Ltd.), and 0.05 parts by mass of tetrabutyl titanate ("TBT", manufactured by Nacalai Tesque Corporation) were charged into a reaction vessel, and a transesterification reaction was carried out by raising the temperature from room temperature to 225°C over 150 minutes. Then, the pressure inside the vessel was gradually reduced and the temperature was further increased, and an initial condensation reaction was carried out over 75 minutes at 245°C and a pressure of 0.9 Torr or less. Furthermore, the polymerization reaction was carried out at 245°C and a pressure of 0.9 Torr or less for 80 minutes to obtain a polyester resin (number average molecular weight: 30,000) which would become the hard segment. 100 parts by mass of aliphatic polycarbonate diol ("Carbonate Diol UH-CARB200," manufactured by Ube Industries, Ltd., number average molecular weight: 2,000, 1,6-hexanediol type) and 7.5 parts by mass of diphenyl carbonate were charged into a separate reaction vessel. The temperature was raised from room temperature to 205°C over 130 minutes, and the reaction was carried out at 205°C and 130 Pa. After 2 hours, the contents were cooled to obtain an aliphatic polycarbonate diol (number average molecular weight: 12,000) which would become the soft segment. Fifty parts by mass of the polyester resin and fifty parts by mass of the aliphatic polycarbonate diol were stirred for one hour at 230-245°C and 130 Pa. After confirming that the contents had become transparent, the mixture was cooled to 220°C under a nitrogen atmosphere. Next, 1.0 part by mass of TMA was added, and stirring was continued for 30 minutes at 200-230°C under a nitrogen atmosphere. The contents were removed and cooled to obtain polyester elastomer resin (A-15). The melting point of the polyester elastomer resin (A-15) was 195°C, the glass transition temperature (Tg) was -10°C, the reduced viscosity was 1.02 dl / g, and the acid value was 80 q / ton. The constituent components of the polyester elastomer resin are shown in Table 5.Note that the mol% values ​​for HS components and SS components in Table 5 represent the proportion of each component when the total carboxylic acid components of the hard segment, the total alcohol components of the hard segment, and the total components constituting the soft segment are each set to 100 mol%.

[0151] (2) Production of the polyester elastomer resin composition According to the composition and content ratio of the resin composition described in Table 5, the catalyst (B) and other additives (C) were kneaded and pelletized with 100 parts by mass of polyester elastomer resin (A-15) using a twin-screw extruder, and then dried under reduced pressure at 100°C for 8 hours to obtain the resin composition.

[0152] Examples 18-25 and Comparative Examples 7-10: Polyester elastomer resins (A-16) to (A-22) and (a-6) were produced in the same manner as in Example 17(1), except that the composition and content ratios were changed as shown in Table 5. Then, the polyester elastomer resin compositions of Examples 18-25 and Comparative Examples 7-10 were produced in the same manner as in Example 17(2), except that the composition and content ratios were changed as shown in Table 5.

[0153] Example 26: Production of Polyester Elastomer Resin Composition (1) Production of Polyester Elastomer Resin (A-23) 100 parts by mass of dimethyl terephthalate ("DMT", manufactured by SK Petrochemical), 98.4 parts by mass of 1,4-butanediol ("1,4-BDO", manufactured by Mitsubishi Chemical Corporation), 0.5 parts by mass of trimellitic anhydride ("TMA", manufactured by Shotan Chemical Co., Ltd.), 3.2 parts by mass of fumaric acid ("FA", manufactured by Fuso Chemical Industry Co., Ltd.), and 0.05 parts by mass of tetrabutyl titanate ("TBT", manufactured by Nacalai Tesque) were charged into a reaction vessel, and a transesterification reaction was carried out by raising the temperature from room temperature to 225°C over 150 minutes. Then, the pressure inside the vessel was gradually reduced and the temperature was further increased, and an initial condensation reaction was carried out over 75 minutes at 245°C and below 0.9 Torr. A polymerization reaction was then carried out for 80 minutes at 245°C and below 0.9 Torr. Next, 88.1 parts by mass of ε-caprolactone ("PLACSEL," manufactured by Daicel Corporation) was added, and the mixture was stirred at 230°C under a nitrogen atmosphere for 2 hours. Then, 1.1 parts by mass of TMA was added, and stirring was continued at 200-230°C under a nitrogen atmosphere for 30 minutes. The contents were removed and cooled to obtain polyester elastomer resin (A-23). ​​The melting point of the polyester elastomer resin (A-23) was 180°C, the glass transition temperature (Tg) was -25°C, the reduced viscosity was 1.44 dl / g, and the acid value was 110 q / ton.

[0154] In Example 27 and Comparative Example 11, polyester elastomer resins (A-24) and (a-7) were produced in the same manner as in Example 17(1), except that the composition and content ratios were changed as shown in Table 5. Then, the polyester elastomer resin compositions of Example 11 and Comparative Example 5 were produced in the same manner as in Example 1(2), except that the composition and content ratios were changed as shown in Table 1.

[0155] Example 28: Production of polyester elastomer resin composition (1) Production of polyester elastomer resin (A-25) 100 parts by mass of dimethyl terephthalate ("DMT", manufactured by SK Petrochemical), 82.6 parts by mass of 1,4-butanediol ("1,4-BDO", manufactured by Mitsubishi Chemical Corporation), 0.5 parts by mass of trimellitic anhydride ("TMA", manufactured by Shotan Chemical Co., Ltd.), 3.2 parts by mass of fumaric acid ("FA", manufactured by Fuso Chemical Industry Co., Ltd.), 92.8 parts by mass of dimergol ("Pripol 2033", manufactured by CRODA), and 0.05 parts by mass of tetrabutyl titanate ("TBT", manufactured by Nacalai Tesque) were charged into a reaction vessel, and a transesterification reaction was carried out by raising the temperature from room temperature to 225°C over 150 minutes. Next, the pressure inside the container was gradually reduced and the temperature was further increased, and the initial condensation reaction was carried out over 75 minutes at 245°C and a pressure of 0.9 Torr or less. After that, the polymerization reaction was carried out for 80 minutes at 245°C and a pressure of 0.9 Torr or less, and then cooled to 220°C under a nitrogen atmosphere. Next, 1.0 part by mass of TMA was added, and stirring was continued for 30 minutes at 200-230°C under a nitrogen atmosphere. The contents were removed and cooled to obtain polyester elastomer resin (A-25). The melting point of the polyester elastomer resin (A-25) was 150°C, the glass transition temperature (Tg) was 2°C, the reduced viscosity was 0.85 dl / g, and the acid value was 70 q / ton.

[0156] Comparative Example 12 A polyester elastomer resin (a-8) was produced in the same manner as in Example 17(1), except that the composition and content ratio were changed as shown in Table 5. Then, the polyester elastomer resin composition of Comparative Example 12 was produced in the same manner as in Example 17(2), except that the composition and content ratio were changed as shown in Table 5.

[0157] The property values ​​of the polyester elastomer resin were measured using Test Examples 1 to 5, and the polyester elastomer resin compositions were evaluated using Test Examples 6 to 12. The results are shown in Table 5.

[0158]

[0159]

[0160] As is clear from the results in Table 5, the resin compositions of Comparative Examples 7 to 12, which did not satisfy the conditions of the present invention and had 0% by mass of NMP insoluble matter after heat treatment, were found to be inferior in terms of elongation at break (heat aging resistance) after heat aging treatment at 200°C for 240 hours, and in hot stiffness at 220°C. Specifically, Comparative Examples 7 to 12 all did not produce NMP insoluble matter after heat treatment, fluidized in a 220°C environment, and failed to satisfy the requirements for heat aging resistance and hot stiffness at 220°C. In particular, in Comparative Example 8, even though it was a polyester elastomer resin with a high melting point, it was found that it failed to satisfy the requirements for heat aging resistance at 200°C and hot stiffness at 220°C.

[0161] In contrast, in Examples 17 to 28 that satisfy the conditions of the present invention, a polyester elastomer resin (A) was used that exhibited a moderate melt flow rate and was thermoplastic, while crosslinking by heat treatment for a predetermined time produced NMP-insoluble material. As a result, it was confirmed that the elongation at break was maintained after heat aging treatment at 200°C for 240 hours, demonstrating excellent heat aging resistance. Furthermore, the storage modulus at 220°C was 1.0 × 10⁻⁶. 4 The temperature reached Pa or higher, which is above the melting point of the polyester elastomer resin (A) used. Even in an environment of 220°C, where the molded article would normally not be able to maintain its shape, it was confirmed that it could maintain its shape and possessed excellent hot rigidity.

[0162] According to the present invention, it is possible to provide a highly heat-resistant resin composition that maintains the flexibility and mechanical properties of an elastomer material while simultaneously achieving both hot rigidity in high-temperature environments of up to 220°C and heat aging resistance in high-temperature environments of around 200°C. Furthermore, the crosslinked molded articles of the present invention can be applied to a wide range of applications, such as various components of electrical products, and covering materials for hoses, tubes, and cables. In addition, it can be applied to various molded products obtained by injection molding, extrusion molding, transfer molding, blow molding, and other methods.

Claims

A crosslinkable polyester elastomer resin composition containing polyester elastomer resin (A), The polyester elastomer resin (A) has a hard segment and a soft segment, The hard segment is formed from a polyester containing an aromatic dicarboxylic acid and an aliphatic diol as constituent components. A crosslinkable polyester elastomer resin composition characterized in that the polyester elastomer resin composition is heat-treated at 240°C for 1 hour, and then the insoluble content after heating in NMP at 150°C for 3 hours is 10% by mass or more. 　 A crosslinkable polyester elastomer resin composition according to claim 1 that satisfies one or more of the following requirements (i) to (v). (i) The soft segment of the polyester elastomer resin (A) contains carbonate bonds and ester bonds. (ii) The polyester elastomer resin (A) contains unsaturated bonds in one or both of the hard segment and the soft segment. (iii) The hard segment and the soft segment of the polyester elastomer resin (A) have a branched skeleton, or one or both of them. (iv) The acid value of the polyester elastomer resin (A) is 80 to 200 eq / ton. (v) The crosslinkable polyester elastomer resin composition contains catalyst (B). 　 A crosslinkable polyester elastomer resin composition according to claim 1, satisfying the following requirements (i) and (vi). (i) The soft segment of the polyester elastomer resin (A) contains carbonate bonds and ester bonds. (vi) The soft segment of the polyester elastomer resin (A) contains unsaturated bonds. 　 A crosslinkable polyester elastomer resin composition according to claim 1 that satisfies the following requirements (iii) and (v). (iii) The hard segment and the soft segment of the polyester elastomer resin (A) have a branched skeleton, or one or both of them. (v) The crosslinkable polyester elastomer resin composition contains catalyst (B). 　 A crosslinkable polyester elastomer resin composition according to claim 1, satisfying the following requirements (iv) and (v). (iv) The acid value of the polyester elastomer resin (A) is 80 to 200 eq / ton. (v) The crosslinkable polyester elastomer resin composition contains catalyst (B). 　 A crosslinkable polyester elastomer resin composition according to claim 1 that satisfies the following requirements (vii) and (viiii). (vii) The hard segment of the polyester elastomer resin (A) contains unsaturated bonds. (viiii) The hard segment of the polyester elastomer resin (A) has a branched skeleton. 　 The crosslinkable polyester elastomer resin composition according to claim 1, wherein the polyester elastomer resin (A) has 20 to 85% by mass of the hard segment and 15 to 80% by mass of the soft segment. 　 The crosslinkable polyester elastomer resin composition according to claim 1, wherein the hard segment of the polyester elastomer resin (A) contains one or both of a trifunctional or more polycarboxylic acid and a trifunctional or more polyol as constituent units, thereby having a branched skeleton. 　 The crosslinkable polyester elastomer resin composition according to claim 1, wherein the carboxylic acid component of the hard segment of the polyester elastomer resin (A) contains 0.5 to 2 mol% of a trifunctional or higher polycarboxylic acid. 　 The crosslinkable polyester elastomer resin composition according to claim 1, wherein the carboxylic acid component of the hard segment or soft segment of the polyester elastomer resin (A) comprises 3 to 20 mol% of an unsaturated dicarboxylic acid. 　 The crosslinkable polyester elastomer resin composition according to claim 2, comprising one or more catalysts selected from the group consisting of tetrabutyl titanate, dodecylbenzenesulfonic acid, and ammonium dodecylbenzenesulfonate salt as the catalyst (B). 　 The polyester elastomer resin composition is heat-treated at 240°C for 1 hour, and then the storage modulus E' at 220°C obtained by dynamic viscoelasticity measurement in accordance with JIS K7244 is 1.0 × 10⁻⁶. 4 The crosslinkable polyester elastomer resin composition according to claim 1, wherein the hardness is Pa or greater. 　 The polyester elastomer resin composition according to claim 1, wherein the insoluble content after heating the polyester elastomer resin composition in NMP at 150°C for 3 hours is less than 10% by mass. 　 A molded article formed from the crosslinkable polyester elastomer resin composition according to any one of claims 1 to 13. 　 A crosslinked molded article formed from the crosslinkable polyester elastomer resin composition according to any one of claims 1 to 13. 　 An extruded article formed from the crosslinkable polyester elastomer resin composition according to any one of claims 1 to 13. 　 A coating material formed from the crosslinkable polyester elastomer resin composition according to any one of claims 1 to 13.

Images