Polyamide block copolymer, polyamide block copolymer composition, molded body and various products containing same, and method for producing polyamide block copolymer

Abstract

The present invention provides a polyamide block copolymer which has high heat resistance and good mechanical properties, while having excellent dimensional stability and insulating properties during water absorption. The present invention relates to a polyamide block copolymer comprising: a polymer block (A) that contains 50 mol% or more of a constituent unit derived from a polyamide and has a glass transition temperature of more than 20°C; and a polymer block (B) that has a glass transition temperature of 20°C or less. The polyamide block copolymer satisfies conditions (i) to (iii). (i) The polyamide block copolymer has a melting point of 190°C or more. (ii) The water absorption rate of the polyamide block copolymer is 5.0% or less. (iii) The tensile elongation at break TE (%) and the tensile elastic modulus TM (MPa) of the polyamide block copolymer, as measured in accordance with JIS K7161-1:2014, satisfy relational expression (1).　(1): TE > 400 - TM / 9

Description

Polyamide block copolymer, polyamide block copolymer composition, molded article and various products containing them, and method for producing polyamide block copolymer

[0001] The present invention relates to a polyamide block copolymer, a polyamide block copolymer composition, a molded article and various products containing them, and a method for producing a polyamide block copolymer.

[0002] Thermoplastic elastomers can be melt-molded and are used in a wide range of fields such as automotive interior and exterior parts, electronic and electrical equipment parts, and sports goods. Thermoplastic elastomers contain a soft segment exhibiting flexibility and a hard segment exhibiting crosslinking points, and are classified into, for example, olefin-based, amide-based, urethane-based, ester-based, acrylic-based, and styrene-based types. Depending on the above classification, thermoplastic elastomers can exhibit physical properties such as good mechanical strength, abrasion resistance, heat resistance, and oil resistance. For example, thermoplastic elastomers such as amide-based, urethane-based, and ester-based types tend to exhibit relatively good heat resistance. However, in each field, further improvement of physical properties according to the application is required, and in order to meet this requirement, studies have been conducted to improve the physical properties of thermoplastic elastomers.

[0003] For example, Patent Document 1 describes a polyamide block copolymer comprising a polymer block (A) containing 50 mol% or more of structural units derived from polyamide and a polymer block (B) containing 50 mol% or more of structural units derived from at least one selected from the group consisting of polyether and polyester, wherein the glass transition temperature of polymer block (B) is 20°C or lower and the melting point is 230°C or higher. Patent Document 2 describes a flexible polyamide comprising units consisting of aliphatic dicarboxylic acid (A1) having 18 or more carbon atoms and / or units consisting of aliphatic diamine (B1) having 18 or more carbon atoms, wherein the total content of units consisting of (A1) and units consisting of (B1) in the polyamide is 10 to 90% by mass and the melting point is 240°C or higher. Patent Document 3 describes a method for producing a polyamide elastomer in which the hard segment is a nylon 66 chain and the soft segment is a polyoxyalkylene chain by a predetermined manufacturing method. Furthermore, Patent Document 4 describes a copolymer of a rigid polyamide block and a flexible polyether block or polyester block, wherein the polyamide block is semi-crystalline and consists of an X.X' / Y.Z type copolyamide, where (i)X.X' is an aliphatic diamine-diacid pair, (ii)Y is an alicyclic diamine, and (iii)Z is an aliphatic and / or aromatic dicarboxylic acid copolymer. Furthermore, Patent Document 5 describes a flexible polyamide film formed by molding a polyamide similar to that in Patent Document 2.

[0004] International Publication No. 2023 / 074726, International Publication No. 2020 / 085360, Japanese Patent Publication No. Hei 1-029429, Japanese Patent Publication No. 2020-519719, International Publication No. 2021 / 106541

[0005] As polyamide block copolymers become more widespread, there is a growing demand for further performance improvements to enable them to withstand use in a variety of applications. For example, coatings for electric wires, busbars, and cables require high heat resistance and good mechanical properties, as well as even better performance in environments where water ingress or wetting may occur, and in high-humidity environments. In particular, when using polyamide block copolymers as coatings, there is a strong demand for high resilience to bending at high temperatures, minimal dimensional change upon water absorption, and maintenance of insulating properties even when water is absorbed. However, the polymers specifically disclosed in the above-mentioned patent documents have not adequately met the above requirements, and there is room for improvement.

[0006] Therefore, the object of the present invention is to provide a polyamide block copolymer that has high heat resistance and good mechanical properties, as well as excellent dimensional stability and insulating properties when water is absorbed.

[0007] As a result of diligent research to solve the above problems, the inventors have come up with the present invention described below and have found that it can solve the problems. That is, the present invention is as follows.

[0008] [1] A polyamide block copolymer comprising a polymer block (A) having a glass transition temperature greater than 20°C and containing 50 mol% or more of structural units derived from polyamide, and a polymer block (B) having a glass transition temperature of 20°C or less, and satisfying the following conditions (i) to (iii): (i) The melting point of the polyamide block copolymer is 190°C or higher. (ii) The water absorption rate of the polyamide block copolymer is 5.0% or less. (iii) The tensile elongation at break TE (%) and the tensile modulus TM (MPa) of the polyamide block copolymer, measured in accordance with JIS K 7161-1:2014, satisfy the following relationship (1): TE > 400 - TM / 9 ... Equation (1) [2] The polyamide block copolymer according to [1] above, wherein the polyamide contains structural units derived from at least one aliphatic diamine selected from the group consisting of linear aliphatic diamines and branched aliphatic diamines. [3] The polyamide block copolymer according to [2], wherein the polyamide comprises a diamine unit mainly composed of a structural unit derived from the aliphatic diamine and a dicarboxylic acid unit mainly composed of a structural unit derived from an aromatic dicarboxylic acid. [4] The polyamide block copolymer according to any one of [1] to [3], wherein the polyamide comprises a structural unit derived from at least one selected from the group consisting of 1,9-nonanediamine and 2-methyl-1,8-octanediamine. [5] The polyamide block copolymer according to any one of [1] to [4], wherein the polyamide comprises a structural unit derived from at least one selected from the group consisting of terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid.

[0009] [6] The polyamide block copolymer according to any one of [1] to [5] above, wherein the polymer block (B) comprises a structural unit selected from at least one of the group consisting of polyether polyols, polyester polyols, polycarbonate polyols, polysiloxane polyols, and their amine derivatives and their carboxyl derivatives. [7] The polyamide block copolymer according to any one of [1] to [6] above, wherein the polymer block (B) comprises a structural unit selected from at least one of the group consisting of polyether polyols, polyester polyols, polycarbonate polyols, and their amine derivatives and their carboxyl derivatives, each comprising a structural unit derived from a hydrocarbon having 3 to 9 carbon atoms. [8] The polyamide block copolymer according to any one of [1] to [7] above, wherein the polymer block (B) comprises a structural unit selected from at least one of the group consisting of a polyether polyol comprising a structural unit derived from an alkylene glycol having 3 to 4 carbon atoms, an amine derivative of the polyether polyol, and a carboxyl derivative of the polyether polyol. [9] The polyamide block copolymer according to any one of [1] to [8] above, wherein the tensile elongation TE of the polyamide block copolymer is 30% or more.

[10] The polyamide block copolymer according to any one of [1] to [9] above, wherein the tensile modulus TM of the polyamide block copolymer is 100 MPa or more and 2,500 MPa or less.

[0010]

[11] The polyamide block copolymer according to any one of [1] to

[10] above, wherein the number average molecular weight Mn of the polyamide block copolymer is 20,000 or more and 500,000 or less.

[12] The polyamide block copolymer according to any one of [1] to

[11] above, wherein the molecular weight distribution (weight average molecular weight Mw / number average molecular weight Mn) of the polyamide block copolymer is 1.0 to 5.0.

[13] A polyamide block copolymer composition comprising the polyamide block copolymer according to any one of [1] to

[12] above.

[14] A molded article comprising at least one selected from the group consisting of the polyamide block copolymer according to any one of [1] to

[12] above and the polyamide block copolymer composition according to

[13] above.

[15] A coating material comprising at least one selected from the group consisting of the polyamide block copolymer according to any one of [1] to

[12] above and the polyamide block copolymer composition according to

[13] above.

[0011]

[16] An electric wire comprising the covering material described in

[15] above.

[17] A bus bar comprising the covering material described in

[15] above.

[18] A cable comprising the covering material described in

[15] above.

[19] A tube comprising at least one selected from the group consisting of the polyamide block copolymer described in any one of [1] to

[12] above and the polyamide block copolymer composition described in

[13] above.

[20] A hose comprising at least one selected from the group consisting of the polyamide block copolymer described in any one of [1] to

[12] above and the polyamide block copolymer described in

[13] above.

[21] A method for producing a polyamide block copolymer according to any one of [1] to

[12] above, wherein the total amount of the second polymer constituting a polymer block (B) to be added to a first polymer constituting a polymer block (A) is 100 mol%, and the second polymer is added to the molten first polymer at an addition rate of 20 mol% / h or less.

[0012] The present invention provides a polyamide block copolymer that has high heat resistance and good mechanical properties, as well as excellent dimensional stability and insulating properties when water is absorbed.

[0013] This graph shows the relationship between the tensile elongation at break (TE) and the tensile modulus (TM) of the polyamide block copolymers in the examples and comparative examples.

[0014] The following description is based on an example of an embodiment of the present invention. However, the embodiments shown below are illustrative examples for realizing the technical concept of the present invention, and the present invention is not limited to the following description. In this specification, preferred forms of embodiments are shown, but combinations of two or more individual preferred forms are also preferred forms. If there are several numerical ranges for an item indicated by a numerical range, a preferred form can be obtained by selectively combining the lower and upper limits of those ranges. In this specification, when a numerical range is described as "XX to YY", it means "XX or more and YY or less". In this specification, "~ unit" (where "~" indicates a monomer) means "a constituent unit derived from ~", for example, "dicarboxylic acid unit" means "a constituent unit derived from a dicarboxylic acid", and "diamine unit" means "a constituent unit derived from a diamine".

[0015] A polyamide block copolymer according to one or more embodiments of the present invention comprises a polymer block (A) having a glass transition temperature greater than 20°C and containing 50 mol% or more of polyamide-derived structural units, and a polymer block (B) having a glass transition temperature of 20°C or less, and satisfies the following conditions (i) to (iii): (i) The melting point of the polyamide block copolymer is 190°C or higher. (ii) The water absorption rate of the polyamide block copolymer is 5.0% or less. (iii) The tensile elongation at break TE (%) and tensile modulus TM (MPa) of the polyamide block copolymer, measured in accordance with JIS K 7161-1:2014, satisfy the following relationship (1): TE > 400 - TM / 9 ... Equation (1)

[0016] Polyamide block copolymers according to one or more embodiments of the present invention (hereinafter also simply referred to as "polyamide block copolymers according to this embodiment") possess high heat resistance and good mechanical properties, and also exhibit excellent dimensional stability and insulation properties when water is absorbed. The reasons for this are not limited to these, but one possible reason is as follows. As described above, conventionally proposed polyamide block copolymers have room for improvement in terms of water absorption, and when a polyamide block copolymer is immersed in water or when moisture adheres to a polyamide block copolymer, water penetrates into the polyamide block copolymer. When more than a certain amount of water penetrates into a polyamide block copolymer, the interaction between molecular chains is inhibited by water molecules, causing the chains to dissociate, increasing the overall dimensions of the polyamide block copolymer and reducing its dimensional stability. In addition, when water, a polar solvent, penetrates a polyamide block copolymer, electrical polarization is induced, which tends to reduce the insulation properties of the polyamide block copolymer. Furthermore, conventionally proposed polyamide block copolymers have the problem that when the resin is bent, tensile deformation occurs on the outer side of the bent surface (mainly the side opposite the bent surface), and especially when bent at high temperatures, the ability to restore to the original shape is insufficient. The polyamide block copolymer according to this embodiment satisfies the above-mentioned conditions (i) to (iii), which suppresses the penetration of water molecules, resulting in good dimensional stability and insulation properties. In addition, the above polyamide block copolymer is considered to have excellent resilience to bending because it can restore deformation with good elongation in the region where the amount of deformation due to elongation is large, and can restore deformation with good elastic modulus in the region where the amount of deformation is small.

[0017] The melting point of the polyamide block copolymer specified in condition (i) above is preferably 200°C or higher, more preferably 220°C or higher, even more preferably 230°C or higher, and even more preferably 235°C or higher, from the viewpoint of heat resistance. There is no particular upper limit to the melting point of the polyamide block copolymer, but from the viewpoint of moldability, etc., 315°C or lower is preferred. In other words, the melting point of the polyamide block copolymer specified in condition (i) above is preferably 190 to 315°C, and more preferably 200 to 315°C. In order to satisfy condition (i) above, for example, a material exhibiting a high melting point can be selected as polymer block (A), or the content of polymer block (A) can be made greater than the content of polymer block (B). The melting point of the polyamide block copolymer is measured by the procedure described in the examples.

[0018] The water absorption rate of the polyamide block copolymer specified in the above condition (ii) is determined by drying the polyamide block copolymer formed to a predetermined size, immersing it in distilled water at a predetermined temperature for a predetermined time, and measuring the change in mass before and after immersion. From the viewpoint of suppressing dimensional changes during water absorption and maintaining insulation properties, the water absorption rate of the polyamide block copolymer is preferably 4.5% or less, more preferably 4.0% or less, even more preferably 3.5% or less, and even more preferably 3.0% or less. There is no lower limit to the water absorption rate and it may be 0%, but from the viewpoint of ease of manufacture, it is, for example, 0.01% or more. In other words, the water absorption rate of the polyamide block copolymer is preferably 0 to 5.0%.

[0019] To satisfy condition (ii) above, for example, materials with low affinity for water can be selected as polymer block (A) and polymer block (B), or the proportion of blocks with low affinity for water can be increased. The water absorption rate is measured in detail by the procedure described in the Examples. To satisfy condition (iii) above, for example, a method for producing a polyamide block copolymer can be employed that includes a step of adding polymer block (B) to the polymer block in small amounts, as described later. The tensile elongation at break TE and tensile modulus TM are measured in accordance with JIS K 7161-1:2014, and are measured in detail by the procedure described in the Examples.

[0020] The tensile elongation TE of the polyamide block copolymer according to this embodiment is preferably 100% or more, more preferably 200% or more, even more preferably 300% or more, and even more preferably 350% or more, from the viewpoint of flexibility. There is no particular upper limit to the tensile elongation TE, but from the viewpoint of ease of manufacture, it is, for example, 900% or less. In other words, the tensile elongation TE of the polyamide block copolymer is preferably 100 to 900%.

[0021] The tensile modulus™ of the polyamide block copolymer according to this embodiment is preferably 100 MPa to 2,500 MPa, more preferably 120 MPa to 2,400 MPa, even more preferably 140 MPa to 2,200 MPa, and even more preferably 160 MPa to 2,100 MPa, from the viewpoint of easily ensuring good mechanical properties.

[0022] The following describes each component constituting the polyamide block copolymer according to this embodiment.

[0023] <Polymer Block (A)> Polymer block (A) contains 50 mol% or more of polyamide-derived structural units and has a glass transition temperature of over 20°C. From the viewpoint of obtaining even better heat resistance, polymer block (A) preferably contains 70 mol% or more, more preferably 90 mol% or more, of polyamide-derived structural units, and may also contain 100 mol%. In other words, the content of polyamide-derived structural units in polymer block (A) is preferably 50 to 100 mol%. In polymer block (A), structural units other than those derived from polyamide are not limited as long as the effects of the present invention can be obtained. The polyamide that can be used in the polyamide block copolymer according to this embodiment is not limited as long as the effects of the present invention can be obtained, and examples include semi-aromatic polyamides, fully aromatic polyamides, and aliphatic polyamides. Among these, semi-aromatic polyamides and aliphatic polyamides are polyamides in which the effects of the present invention are more pronounced. From the viewpoint of obtaining even better heat resistance, it is particularly preferable to use semi-aromatic polyamides as the polyamide. Examples of the aliphatic polyamides mentioned above include polytetramethylene adipamide (polyamide 46) and polyhexamethylene adipamide (polyamide 66). Semi-aromatic polyamides that can be suitably used in the polyamide block copolymer according to this embodiment will be described in detail below.

[0024] [Semi-aromatic polyamide] A semi-aromatic polyamide is a polyamide containing diamine units mainly composed of aliphatic diamine units and dicarboxylic acid units mainly composed of aromatic dicarboxylic acid units, or a polyamide containing dicarboxylic acid units mainly composed of aliphatic dicarboxylic acid units and diamine units mainly composed of aromatic diamine units. Here, "main component" means that they constitute 50 to 100 mol%, preferably 60 to 100 mol%, of the total units. In the polyamide block copolymer according to this embodiment, the semi-aromatic polyamide preferably contains diamine units mainly composed of aliphatic diamine units and dicarboxylic acid units mainly composed of aromatic dicarboxylic acid units, from the viewpoint of making it easier to improve heat resistance. That is, in one preferred embodiment of the present invention, the polyamide contains diamine units mainly composed of constituent units derived from the aliphatic diamine and dicarboxylic acid units mainly composed of constituent units derived from the aromatic dicarboxylic acid.

[0025] (Aliphatic Diamine Units) Semi-aromatic polyamides preferably contain 30 mol% or more of diamine units derived from aliphatic diamines having 4 to 18 carbon atoms, more preferably 30 to 100 mol%, even more preferably 50 to 100 mol%, even more preferably 70 to 100 mol%, even more preferably 90 to 100 mol%, and may contain 100 mol%. Furthermore, as the aliphatic diamine used in the above diamine units, aliphatic diamines having 4 to 16 carbon atoms are more preferably, aliphatic diamines having 4 to 12 carbon atoms are even more preferably, aliphatic diamines having 6 to 12 carbon atoms are even more preferably, and aliphatic diamines having 6 to 10 carbon atoms are even more preferably.

[0026] Examples of aliphatic diamines having 4 to 18 carbon atoms include linear aliphatic diamines such as 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine (hexamethylenediamine), 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,13-tridecanediamine, 1,14-tetradecanediamine, 1,15-pentadecanediamine, 1,16-hexadecanediamine, 1,17-heptadecanediamine, and 1,18-octadecanediamine;1-Butyl-1,2-ethanediamine, 1,1-dimethyl-1,4-butanediamine, 1-ethyl-1,4-butanediamine, 2-ethyl-1,4-butanediamine, 1,2-dimethyl-1,4-butanediamine, 1,3-dimethyl-1,4-butanediamine, 1,4-dimethyl-1,4-butanediamine, 2-methyl-1,3-propanediamine, 2-methyl-1,4-butanediamine, 2,3-dimethyl-1,4-butanediamine, 2-methyl-1, 5-pentanediamine, 3-methyl-1,5-pentanediamine, 2-ethyl-1,5-pentanediamine, 2-propyl-1,5-pentanediamine, 2-butyl-2-ethyl-1,5-pentanediamine, 2,5-dimethyl-1,6-hexanediamine, 2,4-dimethyl-1,6-hexanediamine, 3,3-dimethyl-1,6-hexanediamine, 2,2-dimethyl-1,6-hexanediamine, 2,2,4-trimethyl-1,6-hexanediamine Min, 2,4,4-trimethyl-1,6-hexanediamine, 2-ethyl-1,6-hexanediamine, 2-propyl-1,6-hexanediamine, 2,4-diethyl-1,6-hexanediamine, 2-ethyl-1,7-heptanediamine, 2-propyl-1,7-heptanediamine, 2-methyl-1,8-octanediamine, 3-methyl-1,8-octanediamine, 1,3-dimethyl-1,8-octanediamine, 1,4-dimethyl-1,8-octanediamine Branched aliphatic diamines such as 2,4-dimethyl-1,8-octanediamine, 3,4-dimethyl-1,8-octanediamine, 4,5-dimethyl-1,8-octanediamine, 2,2-dimethyl-1,8-octanediamine, 3,3-dimethyl-1,8-octanediamine, 4,4-dimethyl-1,8-octanediamine, 2-ethyl-1,8-octanediamine, 2-methyl-1,9-nonanediamine, and 5-methyl-1,9-nonanediamine;Examples include alicyclic diamines such as 1,2-cyclohexanediamine, 1,4-cyclohexanediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis(4-aminocyclohexyl)methane, bis(3-methyl-4-aminocyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane, and bis(aminopropyl)piperazine. These may be used individually or in combination of two or more.

[0027] From the viewpoint of heat resistance, it is preferable to use at least one aliphatic diamine selected from the group consisting of linear aliphatic diamines and branched aliphatic diamines, and it is more preferable to use linear aliphatic diamines and branched aliphatic diamines in combination. That is, in a more preferred embodiment of the present invention, the polyamide contains constituent units derived from at least one aliphatic diamine selected from the group consisting of linear aliphatic diamines and branched aliphatic diamines.

[0028] From the viewpoint of more pronounced effects of the present invention and excellent raw material availability, the semi-aromatic polyamide preferably contains a diamine unit derived from at least one selected from the group consisting of 1,4-butanediamine, 1,6-hexanediamine, 1,9-nonanediamine, 2-propyl-1,6-hexanediamine, 2-ethyl-1,7-heptanediamine, 2-methyl-1,8-octanediamine, 1,10-decanediamine, 1,11-undecanediamine, and 1,12-dodecanediamine, more preferably contains a diamine unit derived from at least one selected from the group consisting of 1,9-nonanediamine and 2-methyl-1,8-octanediamine, and from the viewpoint of moldability, it is even more preferable to use both 1,9-nonanediamine and 2-methyl-1,8-octanediamine in combination. In other words, in a more preferred embodiment of the present invention, the polyamide contains constituent units derived from at least one selected from the group consisting of 1,9-nonanediamine and 2-methyl-1,8-octanediamine. The content of at least one of the 1,9-nonanediamine units and 2-methyl-1,8-octanediamine units in the total amount of diamine units constituting the semi-aromatic polyamide is preferably 50 to 100 mol%, more preferably 60 to 100 mol%, even more preferably 75 to 100 mol%, and even more preferably 90 to 100 mol%. When the content of at least one of the 1,9-nonanediamine units and 2-methyl-1,8-octanediamine units in the total amount of diamine units constituting the semi-aromatic polyamide is within the above range, the heat resistance is further improved and excellent chemical resistance can also be expected.

[0029] When 1,9-nonanediamine and 2-methyl-1,8-octanediamine are used in combination, the molar ratio of 1,9-nonanediamine to 2-methyl-1,8-octanediamine is preferably 99:1 to 1:99, more preferably 95:5 to 5:95, even more preferably 90:10 to 10:90, even more preferably 85:15 to 15:85, even more preferably 80:20 to 20:80, even more preferably 70:30 to 30:70, and particularly preferably 65:35 to 35:65. When the molar ratio of 1,9-nonanediamine and 2-methyl-1,8-octanediamine is within the above range, the polymerization reaction with polymer block (B) proceeds well, and excellent heat resistance and flexibility can be expected in the resulting polyamide block copolymer.

[0030] Furthermore, the semi-aromatic polyamide may contain constituent units derived from aliphatic diamines other than aromatic diamines, as long as the effects of the present invention are not impaired. These constituent units derived from aliphatic diamines may be present in groups of one or more types. The content of the constituent units derived from aliphatic diamines in the diamine units is preferably 30 mol% or less, more preferably 20 mol% or less, even more preferably 10 mol% or less, and even more preferably 5 mol% or less.

[0031] (Aromatic Dicarboxylic Acid Units) From the viewpoint of favorable polymerization reactions with diamines and improved physical properties such as heat resistance, aromatic dicarboxylic acid units derived from isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, diphenic acid, 4,4'-biphenyldicarboxylic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, etc. are recommended as aromatic dicarboxylic acid units. From the viewpoint of more significantly exhibiting the effects of the present invention, the semi-aromatic polyamide preferably contains dicarboxylic acid units derived from at least one selected from the group consisting of terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid, and from the viewpoint of further improving heat resistance, it is more preferable to contain dicarboxylic acid units derived from at least one selected from the group consisting of terephthalic acid and 2,6-naphthalenedicarboxylic acid. In other words, in a more preferred embodiment of the present invention, the polyamide contains a constituent unit derived from at least one selected from the group consisting of terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid. These aromatic dicarboxylic acid units may be used individually or in combination of two or more.

[0032] From the viewpoint of heat resistance and mechanical strength, the content of dicarboxylic acid units derived from at least one selected from the group consisting of terephthalic acid and 2,6-naphthalenedicarboxylic acid in the total amount of dicarboxylic acid units constituting the semi-aromatic polyamide is preferably 30 mol% or more, more preferably 30 to 100 mol%, even more preferably 50 to 100 mol%, even more preferably 70 to 100 mol%, even more preferably 90 to 100 mol%, and may also be 100 mol%.

[0033] Furthermore, the semi-aromatic polyamide may contain constituent units derived from aromatic dicarboxylic acids, such as aliphatic dicarboxylic acids, as dicarboxylic acid units, as long as the effects of the present invention are not impaired. These constituent units derived from aromatic dicarboxylic acids may be present as one type or as two or more types. Examples of aliphatic dicarboxylic acids include linear aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, and dimethylmalonic acid; branched aliphatic dicarboxylic acids such as 2,2-diethylsuccinic acid, 2,2-dimethylglutaric acid, 2-methyladipic acid, and trimethyladipic acid; and alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. The content of constituent units other than the above-mentioned aromatic dicarboxylic acid in the dicarboxylic acid unit is preferably 30 mol% or less, more preferably 20 mol% or less, even more preferably 10 mol% or less, and even more preferably 5 mol% or less.

[0034] The content of units derived from the above-mentioned aliphatic diamine having 4 to 18 carbon atoms relative to the total constituent units of the semi-aromatic polyamide is preferably 15 to 55 mol%, and more preferably 25 to 55 mol%. The content of units derived from the above-mentioned aliphatic diamine having 4 to 18 carbon atoms relative to the total constituent units of the semi-aromatic polyamide is preferably 15 to 55 mol%, and more preferably 25 to 55 mol%. The total content of units derived from the above-mentioned aliphatic diamine having 4 to 18 carbon atoms and aromatic dicarboxylic acids relative to the total constituent units of the semi-aromatic polyamide is preferably 30 to 100 mol%, more preferably 50 to 100 mol%, even more preferably 70 to 100 mol%, and may be 90 mol% or more, and may even be 100 mol%.

[0035] (Other constituent units) In addition, the semi-aromatic polyamide may contain other constituent units other than diamine units and dicarboxylic acid units, as long as the effects of the present invention are not impaired. Examples of other constituent units include polycarboxylic acid units, aminocarboxylic acid units and lactam units. Examples of polycarboxylic acid units include constituent units derived from polycarboxylic acids of three or more valents, such as trimellitic acid, trimesic acid, and pyromellitic acid. These polycarboxylic acid units can be included in a range that allows for melt molding. Examples of aminocarboxylic acid units include lactams such as caprolactam and lauryl lactam; and constituent units derived from aminocarboxylic acids such as 11-aminoundecanoic acid and 12-aminododecanoic acid. Examples of lactam units include constituent units derived from ε-caprolactam, enantractam, undecanelactam, lauryl lactam, α-pyrrolidone, α-piperidone, etc. The content of other constituent units relative to the total constituent units of the semi-aromatic polyamide is preferably 30 mol% or less, and more preferably 10 mol% or less.

[0036] Representative semi-aromatic polyamides containing diamine units mainly composed of aliphatic diamine units and dicarboxylic acid units mainly composed of aromatic dicarboxylic acid units include polytetramethylene terephthalamide (Polyamide 4T), polypentamethylene terephthalamide (Polyamide 5T), polyhexamethylene terephthalamide (Polyamide 6T), polynonameethylene terephthalamide (Polyamide 9T), poly(2-methyloctamethylene) terephthalamide (Polyamide M8T), polynonameethylene terephthalamide / poly(2-methyloctamethylene) terephthalamide copolymer (Polyamide 9T / M8T), polynonameethylene naphthalenedicarboxamide (Polyamide 9N), poly(2-methyloctamethylene) naphthalenedicarboxamide (Polyamide M8N), and Examples include linona methylene naphthalenedicarboxamide / poly(2-methyloctamethylene) naphthalenedicarboxamide copolymer (polyamide 9N / M8N), polydecamethylene terephthalamide (polyamide 10T), polyhexamethylene isophthalamide (polyamide 6I), copolymer of polyamide 6I and polyamide 6T (polyamide 6I / 6T), copolymer of polyamide 66, polyamide 6I and polyamide 6T (polyamide 66 / polyamide 6I / 6T), copolymer of polyamide 6T and polyundecaneamide (polyamide 11) (polyamide 6T / 11), copolymer of polyamide 6T and polyamide 10T (polyamide 6T / 10T), and copolymer of polyamide 10T and polyundecaneamide (polyamide 11) (polyamide 10T / 11).

[0037] [End-Sealing Agent] In the polyamide block copolymer according to this embodiment, the polyamide contained in polymer block (A) may contain structural units derived from the end-sealing agent. The content of structural units derived from the end-sealing agent is preferably 1.0 to 10 mol%, more preferably 2.0 to 7.5 mol%, and even more preferably 2.5 to 6.5 mol% relative to the diamine units. The content of structural units derived from the end-sealing agent can be adjusted by the amount of end-sealing agent added relative to the diamine when preparing the polymerization raw materials. It is desirable to fine-tune the amount of end-sealing agent added when preparing the polymerization raw materials so that a desired amount of structural units derived from the end-sealing agent are introduced into the resulting resin, taking into consideration that monomer components volatilize during polymerization. Furthermore, when polymerizing the polymer constituting polymer block (A) and the polymer constituting polymer block (B), the end-sealing agent can be added in the desired range described above. Furthermore, the end-sealing agent can be added to the polymer constituting polymer block (A) together with the end-functionalizing agent described later, in the desired range described above.

[0038] One method for determining the content of constituent units derived from the end-captive agent in polyamide is, for example, as shown in Japanese Patent Publication No. 07-228690, to measure the solution viscosity, calculate the total amount of end groups from the relationship between this viscosity and the number-average molecular weight Mn, and then subtract the amount of amino groups and carboxyl groups determined by titration. As the end-captive agent, monofunctional compounds that have reactivity with terminal amino groups or terminal carboxyl groups can be used. Specifically, examples include monocarboxylic acids, acid anhydrides, monoisocyanates, monoacid halides, monoesters, monoalcohols, monoamines, etc. From the viewpoint of reactivity and stability of the encapsulated ends, monocarboxylic acids are preferred as end-captive agents for terminal amino groups, and monoamines are preferred as end-captive agents for terminal carboxyl groups. From the viewpoint of ease of handling, monocarboxylic acids are more preferred as end-captive agents.

[0039] There are no particular restrictions on the monocarboxylic acid used as a terminal encapsulant, as long as it is reactive with an amino group. Examples of monocarboxylic acids include aliphatic monocarboxylic acids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutyric acid; alicyclic monocarboxylic acids such as cyclopentaneic acid and cyclohexanecarboxylic acid; aromatic monocarboxylic acids such as benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, and phenylacetic acid; and any mixture thereof. Among these, at least one selected from acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, and benzoic acid is preferred in terms of reactivity, stability of the encapsulated end, and cost.

[0040] There are no particular restrictions on the monoamine used as a terminal encapsulant, as long as it is reactive with a carboxyl group. Examples of monoamines include aliphatic monoamines such as methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, and dibutylamine; alicyclic monoamines such as cyclohexylamine and dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine, and naphthylamine; and any mixture thereof. Among these, at least one selected from butylamine, hexylamine, octylamine, decylamine, stearylamine, cyclohexylamine, and aniline is preferred in terms of reactivity, high boiling point, stability of the encapsulated end, and cost.

[0041] [Method for Producing Polyamides] When the polyamide is a semi-aromatic polyamide containing dicarboxylic acid units and diamine units, the above semi-aromatic polyamide can be produced, for example, by melt polymerization, solid-phase polymerization, or melt extrusion polymerization using dicarboxylic acid and diamine as raw materials. Specifically, semi-aromatic polyamides can be produced as follows. First, a nylon salt is produced by mixing a diamine, a dicarboxylic acid, and optionally an aminocarboxylic acid, lactam, catalyst, end-capturing agent, etc. Next, the produced nylon salt is heated to a temperature of 200 to 250°C and heated to obtain a semi-aromatic polyamide as a prepolymer. Furthermore, the semi-aromatic polyamide can be adjusted to a desired molecular weight by solid-phase polymerization of the prepolymer or by increasing the degree of polymerization using a melt extruder. When the step of increasing the degree of polymerization is carried out by solid-phase polymerization, it is preferable to carry it out under reduced pressure or under inert gas flow, and if the polymerization temperature is in the range of 200 to 280°C, the polymerization rate is large, productivity is excellent, and discoloration and gelation can be effectively suppressed. Furthermore, when the step of increasing the degree of polymerization is carried out using a melt extruder, the polymerization temperature is preferably 370°C or lower. When polymerization is carried out under these conditions, a semi-aromatic polyamide with almost no decomposition and minimal degradation is obtained.

[0042] As catalysts that can be used in the production of semi-aromatic polyamides, for example, phosphoric acid, phosphorous acid, hypophosphorous acid, or salts or esters thereof, etc. can be mentioned. Examples of the above salts or esters include salts of phosphoric acid, phosphorous acid or hypophosphorous acid with metals such as potassium, sodium, magnesium, vanadium, calcium, zinc, cobalt, manganese, tin, tungsten, germanium, titanium, antimony, etc.; ammonium salts of phosphoric acid, phosphorous acid or hypophosphorous acid; ethyl esters, isopropyl esters, butyl esters, hexyl esters, isodecyl esters, octadecyl esters, decyl esters, stearyl esters, phenyl esters, etc. of phosphoric acid, phosphorous acid or hypophosphorous acid. The amount of the catalyst used is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, based on 100% by mass of the total mass of the raw materials of the semi-aromatic polyamide. Also, the amount of the catalyst used is preferably 1.0% by mass or less, more preferably 0.5% by mass or less. In other words, the amount of the catalyst used based on the total mass of the raw materials of the semi-aromatic polyamide is preferably 0.01 to 1.0% by mass. If the amount of the catalyst used is at or above the above lower limit value, the polymerization proceeds more favorably.

[0043] [Melting point] The melting point of the polyamide used for the polymer block (A) is preferably 230 °C or higher, more preferably 240 °C or higher, and still more preferably 250 °C or higher. If the melting point of the polyamide is 230 °C or higher, it is easier to further improve the heat resistance of the polyamide block copolymer. There is no particular limitation on the upper limit of the melting point of the polyamide, but from the viewpoint of moldability, etc., it is preferably 320 °C or lower. That is, the melting point of the polyamide is preferably 230 °C or higher and 320 °C or lower. The above melting point can be determined as the peak temperature of the melting peak that appears when the temperature is raised at a rate of 10 °C / min using a differential scanning calorimetry (DSC) device.

[0044] [Molecular Weight] The number-average molecular weight Mn of polymer block (A) is preferably 300 to 12,000, more preferably 300 to 11,000, even more preferably 350 to 10,000, even more preferably 400 to 9,000, and even more preferably 400 to 8,000, and may also be 400 to 7,000 or 400 to 6,000. Within the above numerical range, polymer block (A) and polymer block (B) can be polymerized more easily in a uniformly mixed state, and the heat resistance of the polyamide block copolymer can be further improved. The weight-average molecular weight Mw of polymer block (A) is preferably 1,000 to 50,000, more preferably 1,100 to 45,000, even more preferably 1,200 to 40,000, even more preferably 1,300 to 40,000, and even more preferably 1,400 to 36,000, and may also be 1,400 to 25,000 or 1,400 to 20,000. Within the above numerical range, polymer block (A) and polymer block (B) can be polymerized more easily in a uniformly mixed state, further improving the heat resistance of the polyamide block copolymer. The number-average molecular weight Mn and weight-average molecular weight Mw of polymer block (A) can be measured by gel permeation chromatography, and more specifically, the values ​​measured by the method described in the examples.

[0045] <Polymer Block (B)> Polymer block (B) is a polymer block having a glass transition temperature of 20°C or lower. A glass transition temperature of 20°C or lower in polymer block (B) makes it easier for the polyamide block copolymer to exhibit good flexibility. From the viewpoint of making it easier for the polyamide block copolymer to exhibit excellent flexibility at room temperature, the glass transition temperature of polymer block (B) is more preferably 0°C or lower, and even more preferably -20°C or lower. In this specification, the glass transition temperature can be determined using a differential scanning calorimetry (DSC) apparatus as the temperature of the inflection point that appears when the temperature is increased at a rate of 10°C / min. More specifically, it can be determined by the method described in the examples below. Literature values ​​or manufacturer's measurement results can also be adopted as the above glass transition temperature.

[0046] (First Aspect of Polymer Block (B)) In the polyamide block copolymer according to an embodiment of the present invention, the first aspect of the polymer block (B) includes at least one selected from the group consisting of units composed of an aliphatic dicarboxylic acid (Ba) having 18 or more carbon atoms and units composed of an aliphatic diamine (Bb) having 18 or more carbon atoms.

[0047] In the first aspect of the polymer block (B), the total content of the units composed of the above (Ba) and the units composed of (Bb) in the polymer block (B) is preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 90 mol% or more, and can also be 100 mol% from the viewpoint of easily obtaining excellent flexibility. In other words, the total content of the units composed of the above (Ba) and the units composed of (Bb) in the polymer block (B) is preferably 50 to 100 mol%.

[0048] The aliphatic dicarboxylic acid (Ba) having 18 or more carbon atoms is preferably composed of hydrocarbons except for the carboxyl group, and examples thereof include hexadecanedicarboxylic acid (18 carbon atoms), octadecanedicarboxylic acid (20 carbon atoms), and dimer acid (36 carbon atoms).

[0049] The aliphatic diamine (Bb) having 18 or more carbon atoms is preferably composed of hydrocarbons except for the amino group, and examples thereof include octadecanediamine (18 carbon atoms), eicosanediamine (20 carbon atoms), and dimerdiamine (36 carbon atoms).

[0050] (Second aspect of polymer block (B)) In the polyamide block copolymer according to this embodiment, the second aspect of polymer block (B) includes a constituent unit derived from polyether polyols, polyester polyols, polycarbonate polyols, polysiloxane polyols, and at least one selected from the group consisting of amine derivatives thereof (in other words, amine derivatives of polyether polyols, amine derivatives of polyester polyols, amine derivatives of polycarbonate polyols, and amine derivatives of polysiloxane polyols) and carboxyl derivatives thereof (in other words, carboxyl derivatives of polyether polyols, carboxyl derivatives of polyester polyols, carboxyl derivatives of polycarbonate polyols, and carboxyl derivatives of polysiloxane polyols).

[0051] The second embodiment of polymer block (B), compared to the first embodiment described above, is generally less miscible with polymer block (A), which is composed of polyamide. This makes it easier to form a phase-separated structure, but it also makes polymerization in a uniformly mixed state more difficult. However, by the manufacturing method described later, polymerization can be carried out in a uniformly mixed state, thereby obtaining a high molecular weight polyamide block copolymer while forming a phase-separated structure.

[0052] In a second embodiment of polymer block (B), the content of constituent units in polymer block (B) derived from at least one selected from the group consisting of the polyether polyol, polyester polyol, polycarbonate polyol, polysiloxane polyol, and their amine derivatives and their carboxyl derivatives is preferably 50 mol% or more, more preferably 70 mol% or more, even more preferably 90 mol% or more, and can also be 100 mol%, from the viewpoint of easily obtaining excellent flexibility. In other words, the above content is preferably 50 to 100 mol%.

[0053] In polymer block (B), structural units other than those derived from at least one selected from the group consisting of the polyether polyol, polyester polyol, polycarbonate polyol, polysiloxane polyol, and their amine derivatives are not limited as long as the effects of the present invention can be obtained.

[0054] In one embodiment of the polyamide block copolymer according to the present invention, the polymer block (B) includes a constituent unit derived from polyether polyols, polyester polyols, polycarbonate polyols, and at least one selected from the group consisting of amine derivatives and carboxyl derivatives thereof, which include a constituent unit derived from a hydrocarbon having 3 to 9 carbon atoms.

[0055] In one embodiment of the polyamide block copolymer according to the present invention, the polymer block (B) includes a constituent unit derived from at least one selected from the group consisting of a polyether polyol containing a constituent unit derived from an alkylene glycol having 3 to 4 carbon atoms, an amine derivative of the polyether polyol, and a carboxyl derivative of the polyether polyol.

[0056] [Polyether Polyols] Examples of polyether polyols include polyethylene glycol (PEG), polypropylene glycol (PPG), polytrimethylene ether glycol (PO3G), polytetramethylene glycol (PTMG), poly(3-methyltetrahydrofuran), polypentamethylene ether glycol, polyhexamethylene ether glycol, polyoctamethylene ether glycol, and copolymers thereof. One or more of these can be used.

[0057] [Polyester Polyols] Examples of polyester polyols include condensed polyester polyols and lactone-based polyester polyols. Examples of condensed polyester polyols include those obtained by reacting a dicarboxylic acid with a polyhydric alcohol. Examples of aliphatic dicarboxylic acids or their lower alkyl esters include malonic acid, glutaric acid, adipic acid, succinic acid, azelaic acid, pimelic acid, sebacic acid, and phthalic acid. Examples of alicyclic dicarboxylic acids include 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. Examples of aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, diphenic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, and 4,4'-biphenyldicarboxylic acid. Examples of polyhydric alcohols include aliphatic diols without side chains such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, and 1,10-decamethylene glycol, and aliphatic diols with side chains such as 1,2-propylene glycol, 1,3-butanediol, 3-methyl-1,5-pentanediol, 2,5-dimethyl-2,5-hexanediol, 2,2-diethyl-1,3-propanediol, and neopentyl glycol. Examples of lactone-based polyester polyols include those obtained by reacting lactone compounds such as β-propiolactone, pivalolactone, δ-valerolactone, ε-caprolactone, methyl-ε-caprolactone, dimethyl-ε-caprolactone, and trimethyl-ε-caprolactone with hydroxyl compounds such as short-chain polyols. One or more of these can be used.

[0058] [Polycarbonate Polyols] As polycarbonate polyols, for example, those produced by the esterification reaction of a carbonate ester with a polyhydric alcohol, or those produced by the interfacial polycondensation method of reacting a polyhydric alcohol with phosgene can be used. One or more types of polycarbonate polyols can be used. Examples of carbonate esters include methyl carbonate, ethyl carbonate, and phenyl carbonate. One or more types of these can be used. Examples of polyhydric alcohols include ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, and 1,4-cyclohexanedimethanol. These can be used in one or more types.

[0059] [Polysiloxane polyols] Examples of polysiloxane polyols include dimethylpolysiloxane polyol and methylphenylpolysiloxane polyol.

[0060] [Amine Derivatives] Examples of amine derivatives of the above polyether polyol include polyethylene glycol (PEG), polypropylene glycol (PPG), polytrimethylene ether glycol (PO3G), polytetramethylene glycol (PTMG), poly(3-methyltetrahydrofuran), polypentamethylene ether glycol, polyhexamethylene ether glycol, and polyoctamethylene ether glycol, as well as polymers or copolymers having an amino group introduced at their termini, selected from the group consisting of these. One or more of these can be used. Examples of amine derivatives of polyester polyols include polymers or copolymers with amino groups introduced at the ends of copolymers selected from the group consisting of poly(caprolactone)diol (PCL), poly(methylvalerolactone)diol, poly(ethylene adipate)glycol, poly(butylene-1,4-adipate)glycol (PBA), poly(methylpentanediol adipate)glycol, and poly(butylene-1,4-hexanediol-1,6-adipate)glycol, as well as copolymers containing a composition derived from one or more of these. One or more of these can be used. Examples of amine derivatives of polycarbonate polyols include polymers or copolymers with amino groups introduced at the ends of copolymers selected from the group consisting of poly(hexanediol-1,6-carbonate), poly(3-methylpentanediol-1,5-carbonate), and polytetrahydrofuran carbonate, as well as copolymers containing a composition derived from one or more of these. One or more of these can be used. Examples of amine derivatives of polysiloxane polyols include polymers or copolymers selected from the group consisting of dimethylpolysiloxane polyol, methylphenylpolysiloxane polyol, and copolymers containing a composition derived from one or more of these, or copolymers in which an amino group has been introduced to the terminal. One or more of these can be used.

[0061] [Carboxyl Derivatives] Examples of carboxyl derivatives of the above polyether polyol include polyethylene glycol (PEG), polypropylene glycol (PPG), polytrimethylene ether glycol (PO3G), polytetramethylene glycol (PTMG), poly(3-methyltetrahydrofuran), polypentamethylene ether glycol, polyhexamethylene ether glycol, and polyoctamethylene ether glycol, as well as polymers or copolymers having a carboxyl group introduced at their termini, selected from the group consisting of these. One or more of these can be used. Examples of carboxyl derivatives of polyester polyols include polymers or copolymers selected from the group consisting of poly(caprolactone)diol (PCL), poly(methylvalerolactone)diol, poly(ethylene adipate)glycol, poly(butylene-1,4-adipate)glycol (PBA), poly(methylpentanediol adipate)glycol, and poly(butylene-1,4-hexanediol-1,6-adipate)glycol, as well as copolymers containing a composition derived from one or more of these, with a carboxyl group introduced at the end of the copolymer. One or more of these can be used. Examples of carboxyl derivatives of polycarbonate polyols include polymers or copolymers selected from the group consisting of poly(hexanediol-1,6-carbonate), poly(3-methylpentanediol-1,5-carbonate), and polytetrahydrofuran carbonate, as well as copolymers containing a composition derived from one or more of these, with a carboxyl group introduced at the end of the copolymer. One or more of these can be used. Examples of carboxyl derivatives of polysiloxane polyols include polymers or copolymers selected from the group consisting of dimethylpolysiloxane polyol, methylphenylpolysiloxane polyol, and copolymers containing a structure derived from one or more of these, with a carboxyl group introduced at the end of the copolymer. One or more of these can be used.

[0062] [Molecular Weight] The number-average molecular weight Mn of polymer block (B) is preferably 200 to 5,000, more preferably 230 to 4,000, even more preferably 300 to 2,000, and may also be 350 to 1,500 or 350 to 1,000. Within the above numerical range, the polymerization reaction with polymer block (A) proceeds well, and the flexibility of the polyamide block copolymer becomes even better. The weight-average molecular weight Mw of polymer block (B) is preferably 200 to 5,000, more preferably 230 to 4,000, even more preferably 300 to 2,000, and may also be 350 to 1,500 or 350 to 1,000. Within the above numerical range, the polymerization reaction with polymer block (A) proceeds well, and the flexibility of the polyamide block copolymer becomes even better. The number-average molecular weight Mn and weight-average molecular weight Mw of polymer block (B) can be measured by gel permeation chromatography, and more specifically, by the method described in the examples.

[0063] <Total Content of Polymer Blocks (A) and (B)> From the viewpoint of easily exhibiting the desired properties, the total content of polymer blocks (A) and polymer blocks (B) in the polyamide block copolymer according to this embodiment is preferably 100% by mass when the mass of the polyamide block copolymer is 100% by mass. However, within the range in which the effects of the present invention can be obtained, for example, by-products that are inevitably generated during production may be included. Therefore, the above total content is, for example, 95% by mass or more, preferably 98% by mass or more, and more preferably 99% by mass or more. That is, the total content of polymer blocks (A) and polymer blocks (B) in the polyamide block copolymer is preferably 95 to 100% by mass. As will be described later, additives can also be added to the polyamide block copolymer for the purpose of imparting specific functions to it. In this specification, a polyamide block copolymer containing such additives is referred to as a polyamide block copolymer composition.

[0064] <Mass Ratio (A) / (B)> In the polyamide block copolymer according to this embodiment, the mass ratio (A) / (B) of polymer block (A) to polymer block (B) is preferably in the range of 1 / 99 to 99 / 1. If the mass ratio (A) / (B) is within the above range, it becomes easier to impart excellent flexibility to the polyamide block copolymer. From the viewpoint of achieving both heat resistance and flexibility, the mass ratio (A) / (B) is preferably 5 / 95 to 95 / 5, more preferably 10 / 90 to 95 / 5, even more preferably 20 / 80 to 95 / 5, and may also be 30 / 70 to 95 / 5, 40 / 60 to 95 / 5, 40 / 60 to 90 / 10, 45 / 55 to 90 / 10, or 50 / 50 to 90 / 10.

[0065] <Molecular Weight of Polyamide Block Copolymer> The number-average molecular weight Mn of the polyamide block copolymer according to this embodiment is preferably 20,000 to 500,000, more preferably 25,000 to 250,000, even more preferably 30,000 to 125,000, and even more preferably 35,000 to 100,000, from the viewpoint of ensuring excellent heat resistance while ensuring moldability. The weight-average molecular weight Mw of the polyamide block copolymer according to this embodiment is preferably 40,000 to 350,000, more preferably 50,000 to 300,000, even more preferably 60,000 to 250,000, and even more preferably 70,000 to 200,000, from the viewpoint of ensuring excellent mechanical properties while ensuring moldability. Within the above numerical ranges, the polyamide block copolymer can be expected to exhibit tougher material properties and good moldability.

[0066] The molecular weight distribution (weight-average molecular weight Mw / number-average molecular weight Mn) of the polyamide block copolymer according to this embodiment is preferably 1.0 to 5.0, more preferably 1.2 to 4.0, even more preferably 1.4 to 3.5, and even more preferably 1.6 to 3.0, from the viewpoint of ensuring excellent heat resistance while ensuring moldability. The number-average molecular weight Mn, weight-average molecular weight Mw, and molecular weight distribution Mw / Mn can be measured by gel permeation chromatography, and more specifically, they are values ​​measured by the method described in the examples.

[0067] [Polyamide Block Copolymer Composition] As one embodiment of the present invention, a polyamide block copolymer composition can be provided, which contains any of the above-mentioned polyamide block copolymers. The polyamide block copolymer composition is produced by adding components other than the polyamide block copolymer to the above-mentioned polyamide block copolymer. Examples of such components include antioxidants, ozone cracking inhibitors, weather stabilizers, ultraviolet absorbers, hydrolysis-resistant stabilizers, fillers, crystal nucleating agents, strengthening agents, carbon black, pigments, inorganic dyes, organic dyes, colorants, color inhibitors, gelation inhibitors, matting agents, antistatic agents, plasticizers, lubricants, mold release agents, shrinkage-resistant agents, compatibilizers, flame retardants, flame retardant aids, and foaming agents. These may be present individually or in combination of two or more types.

[0068] The content of the above-mentioned additive is not particularly limited as long as it does not impair the effects of the present invention, but it can be 0.02 to 200 parts by mass per 100 parts by mass of polyamide block copolymer. In other words, the content of polyamide block copolymer in the above-mentioned polyamide block copolymer composition can be 33.3 to 99.9% by mass. By containing the above-mentioned additive within the above range, the above-mentioned polyamide block copolymer composition exhibits the specific functions of the above-mentioned additive and achieves the same technical effects as the polyamide block copolymer according to this embodiment. Examples of methods for adding the above-mentioned additive include adding it during polymerization of the polyamide block copolymer, or dry blending it into the polyamide block copolymer and melt kneading it.

[0069] (Method for Producing Polyamide Block Copolymer Composition) There are no particular limitations on the method for producing the polyamide block copolymer composition. Preferably, a method can be employed in which the above-mentioned additive is added to a first polymer for polymer block (A) to bring it to a melt state, and then a second polymer for polymer block (B) is added thereto, or a method can be employed in which the polyamide block copolymer and the above-mentioned additive can be uniformly mixed. The former method is similar to the method for producing the polyamide block copolymer described later, except that the above-mentioned additive is added to the first polymer for polymer block (A). In the latter method, mixing is usually preferably carried out by melt kneading using a single-screw extruder, twin-screw extruder, kneader, Banbury mixer, etc. There are no particular limitations on the melt kneading conditions, but for example, a method can be given in which melt kneading is carried out for about 1 to 120 minutes at a temperature range about 0 to 60°C higher than the melting point of the polyamide block copolymer.

[0070] [Molded articles and various products] In one embodiment of the present invention, a molded article can be provided that comprises at least one selected from the group consisting of any of the above polyamide block copolymers and the above polyamide block copolymer compositions. The above molded article can be used as various molded articles of any shape and use, such as electrical and electronic components, automotive parts, industrial parts, fibers, films, sheets, household goods, and other products.

[0071] Examples of the above-mentioned molded articles include coatings, tubes, and hoses, each containing at least one selected from the group consisting of any of the above-mentioned polyamide block copolymers and any of the above-mentioned polyamide block copolymer compositions. Here, a tube refers to a narrow, tubular molded article (approximately 0.1 to 10 mm in diameter). A hose refers to a tubular molded article that is thicker than the above-mentioned tube.

[0072] Examples of products containing the above-mentioned covering material include electric wires, busbars, and cables.

[0073] <Applications> The polyamide block copolymer and polyamide block copolymer composition according to this embodiment possess high heat resistance and good mechanical properties, as well as excellent dimensional stability and insulation properties when water is absorbed, making them suitable for use in a wide range of fields where these properties are required. For example, the polyamide block copolymer and polyamide block copolymer composition according to this embodiment can be widely used as materials for various components such as electrical and electronic components, automotive parts, industrial materials, industrial parts, daily necessities, household goods, sports equipment, leisure equipment, and medical equipment. In particular, they can be applied to complex-shaped parts by injection molding, hollow molded parts by blow molding, hose and tube-shaped parts, films and sheets by extrusion molding, lightweight members and heat insulating materials by at least one of injection molding and extrusion foam molding, and as additives for resin modification.

[0074] More specifically within electronic and electrical components, it can be used as a material for mobile phone and game console hinges, camera grips, printer tractor belts, wire insulation, and tubing for home appliances. More specifically within automotive parts, it can be used as a material for constant velocity joint boot components, coiled cords, airbag doors, hydraulic hoses, shift levers, cable liners, automotive belts, fuel tether caps, door locks, steering switches, seat locks, accelerator pedals, air ducts, airless tires, tire frames, and tire inner liners. More specifically within at least one of industrial materials and industrial parts, it can be used as a material for submersible pumps, sealing members, bushings, coverings, hoses, tubes, spiral tubes, diaphragms, mop joints, valves, plastic magnets, noiseless gears, mandrels, films, industrial process tapes, carrier tapes, dicing tapes, backgrind tapes, heat-resistant adhesive tapes, various release films, magnetic tapes, conductive films, nonwoven fabrics, monofilaments, ball joint sheets, register rods, fire hoses, conveyor belts, pulleys, and wire cables. Particularly preferred are covering materials for covering linear, rod-shaped, and plate-shaped conductors, and more specifically, covering materials for electric wires, covering materials for busbars, and covering materials for cables. More specifically within the realm of daily necessities and household goods, they can be used as materials for hair dryer brushes, nail polish cases, hot curlers, zipper pulls, bobbin cases, console shutters, corrugated tubing, corrugated hoses, etc. More specifically within the realm of sports components, they can be used as materials for running shoes, spiked shoes, ski boots, etc. More specifically within the realm of medical components, they can be used as materials for medical catheters, wearable devices, optical products, eye care components, etc.

[0075] <Method for producing polyamide block copolymer> The method for producing a polyamide block copolymer according to this embodiment is a method for producing any of the above-described polyamide block copolymers, and includes a step (polymer addition step) of adding the second polymer to the molten first polymer at an addition rate of 20 mol% / h or less, when the total amount of the second polymer constituting the polymer block (B) to be added to the first polymer constituting the polymer block (A) is 100 mol%.

[0076] When two polymer blocks with different properties are selected, such as polymer block (A) and polymer block (B) constituting the polyamide block copolymer according to this embodiment, it is generally difficult to obtain a high molecular weight polymer due to insufficient contact between the molecules. However, in the method for producing the polyamide block copolymer according to this embodiment, a high molecular weight polyamide block copolymer is produced by having the polymer addition step described above. The reason for this is not limited to this, but one reason is that by adding the second polymer to the molten first polymer in small amounts, the interfacial area between the first polymer and the second polymer is increased, promoting polymerization, and the dispersibility of the second polymer is sufficiently enhanced by the presence of oligomers of the block copolymer temporarily produced by polymerization, as a result, a high molecular weight polyamide block copolymer can be obtained. Furthermore, although polymer block (B) according to the second embodiment tends to decompose more easily during polymerization than polymer block (B) according to the first embodiment, decomposition is suppressed by adding it in small amounts through the polymer addition step, as a result, a high molecular weight polyamide block copolymer can be obtained even when using polymer block (B) according to the second embodiment.

[0077] In the polymer addition step described above, the rate at which the second polymer is added is preferably 20 mol% / h or less, more preferably 15 mol% / h or less, and even more preferably 10 mol% / h or less, when the total amount of the second polymer is 100 mol%, from the viewpoint of easily obtaining a high molecular weight polyamide block copolymer. There is no particular lower limit to the rate at which the second polymer is added, but from the viewpoint of productivity, it is set to, for example, 2 mol% / h or more. In other words, the rate at which the second polymer is added in the polymer addition step described above is preferably 2 to 20 mol% / h.

[0078] The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to these.

[0079] <Measurement and Evaluation Methods> Various physical properties were measured or evaluated using the following methods.

[0080] [Molecular Weight] The first polymer used as polymer block (A) was used as a sample, and the number-average molecular weight Mn was determined as the molecular weight equivalent to standard polymethyl methacrylate by gel permeation chromatography (GPC). The number-average molecular weight Mn of the material used as polymer block (B) was the catalog value. Furthermore, the polyamide block copolymers obtained in the examples and comparative examples were used as samples, and the number-average molecular weight Mn, weight-average molecular weight Mw, and molecular weight distribution Mw / Mn were determined as the molecular weight equivalent to standard polymethyl methacrylate by gel permeation chromatography (GPC). In the above GPC, an HFIP solution prepared by dissolving sodium trifluoroacetate at a ratio of 0.85 g per 1 kg of 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) was used as the eluent. 1.5 mg of the sample (in resin equivalent) was weighed and dissolved in 3 mL of the above eluent, and the eluent was passed through a 0.4 μm membrane filter to prepare a measurement sample. The measurement conditions were as follows. (Measurement conditions) Apparatus: HLC-8320GPC (Tosoh Corporation) Column: Two TSK gel Super HM-H columns (Tosoh Corporation) connected in series. Eluent: 0.085% sodium trifluoroacetate / HFIP solution Flow rate: 0.5 mL / min (Reference column: 0.25 mL / min) Sample injection volume: 30 μL Column temperature: 40°C Standard polymethyl methacrylate: Shodex Standard M-75 (Resonac Corporation), Polymethylmethacrylate (Polymethyl methacrylate with molecular weights of 1,010 and 535) (Agilent Technologies) Detector: RI detector

[0081] [Melting Point Tm] The polyamide block copolymers obtained in the examples and comparative examples were used as samples, and their melting points were measured using a differential scanning calorimetry analyzer "DSC25" manufactured by TA Instruments, Inc. The melting points were measured in accordance with ISO 11357-3 (2nd edition, 2011). Specifically, the sample was heated from 30°C to 300°C at a rate of 10°C / min under a nitrogen atmosphere, held at 300°C for 5 minutes to completely melt the sample, and then cooled to 50°C at a rate of 10°C / min and held at 50°C for 5 minutes. The peak temperature of the melting peak that appeared when the temperature was raised again to 300°C at a rate of 10°C / min was defined as the melting point Tm (°C). If there were multiple melting peaks, the peak temperature of the highest temperature melting peak was defined as the melting point Tm (°C).

[0082] [Glass Transition Temperature Tg] The glass transition temperature Tg was measured using a differential scanning calorimetry analyzer "DSC25" manufactured by TA Instruments Corporation, with the first polymer used in polymer block (A) as a sample. The glass transition temperature was measured in accordance with ISO 11357-3 (2nd edition, 2011). Specifically, the temperature at the inflection point in the DSC curve, measured by heating from -90°C to +300°C at a heating rate of 10°C / min, was defined as the glass transition temperature Tg (°C). The Tg of the second polymer used in polymer block (B) is the catalog value.

[0083] [Hot Press Molding] The polyamide block copolymers obtained in the examples and comparative examples were subjected to a single-acting compression molding machine (IMC-183B, manufactured by Imoto Seisakusho Co., Ltd.) and a 1 mm thick press mold. The pressure was reduced to -0.1 MPaG using an oil rotary pump, preheated to the melting point + 15°C for 3 minutes, and then subjected to 50 kN (12.7 kgf / cm²). ２ It was then pressed for 1 minute using a cooling press with water jet cooling at 30 kgf / cm². ２ A 1 mm thick sheet was produced by pressing it for 5 minutes. Using the produced sheet, the water absorption rate, tensile modulus, tensile breaking strength, tensile breaking elongation, bending recovery at high temperatures, dimensional change rate when water is absorbed, and insulation properties were evaluated as follows.

[0084] [Water Absorption Rate] A 1 mm thick sheet produced by the above-mentioned hot press molding was cut into 10 mm x 50 mm strips to form test specimens. These were dried at 120°C under reduced pressure for 6 hours, and the mass of the dried test specimens was measured. After drying, the test specimens were immersed in distilled water at 23°C for 24 hours, then removed from the water, the water adhering to the surface was wiped off, and the mass of the test specimens after water absorption was measured. From the obtained masses of the test specimens before and after water absorption, the water absorption rate (%) of the resin was calculated based on the following formula: Water absorption rate (%) = 100 × (Mass after water absorption - Mass before water absorption) / Mass before water absorption

[0085] [Tensile modulus™, tensile breaking strength TS, tensile elongation at break TE] In accordance with JIS K 7161-1:2014, the tensile modulus™, tensile breaking strength TS, and tensile elongation at break TE were measured for the polyamide block copolymers obtained in the examples and comparative examples. Specifically, dumbbell-shaped No. 3 test specimens were prepared by punching out a 1 mm thick sheet made by the above-mentioned hot press molding. The test specimens were then pulled at a speed of 0.25 mm / min up to a strain of 0.3%, and at a speed of 50 mm / min thereafter, and stress-strain curves were obtained. The slope of the stress-strain curve corresponding to the two points of strain 0.05% and 0.25% was defined as the tensile modulus™ (MPa), the stress at the breaking point as the tensile breaking strength TS (MPa), and the strain as the tensile elongation at break TE (%).

[0086] [Bending recovery under high temperature] A 1 mm thick sheet produced by the above-mentioned hot press molding was cut into 10 mm x 100 mm strips to serve as test specimens. The test specimens were then bent into a U-shape along a 13 mm diameter metal rod, and a 20 mm area from the end was fixed with clips. The specimens were then heated in a 120°C oven for 1 hour. After removing from the oven, they were allowed to cool in a 23°C laboratory for 30 minutes, and then the clips were removed and the specimens were left to stand for another 30 minutes. The shortest distance between one clip-fixed part of the specimen and the other clip-fixed part was measured after standing. A distance of 20 mm or more but less than 60 mm was evaluated as "A", a distance of 10 mm or more but less than 20 mm was evaluated as "B", and a distance of less than 10 mm was evaluated as "C". "A" and "B" were considered pass, and "C" was considered fail.

[0087] [Dimensional change rate during water absorption] A 1 mm thick sheet produced by the above-mentioned hot press molding was cut into 10 mm x 50 mm strips to form test specimens. These were then dried at 120°C under reduced pressure (100 Pa or less) for 6 hours, and the length of the long side of the dried test specimen was measured. After drying, the test specimen was immersed in distilled water at 23°C for 24 hours, then removed from the water, and the length of the long side of the test specimen after water absorption was measured. From the obtained lengths of the long side of the test specimen before and after water absorption, the dimensional change rate (%) of the resin during water absorption was calculated. Dimensional change rate (%) = 100 × (Length of long side after water absorption - Length of long side before water absorption) / Length of long side before water absorption

[0088] [Volume Resistivity After Water Absorption] The volume resistivity of the polyamide block copolymers obtained in each example and comparative example was measured in accordance with JIS C 2139-3-1:2018. Specifically, a 1 mm thick sheet produced by the above-mentioned hot press molding was cut into a 100 mm x 100 mm square to make a test piece, which was then conditioned in a test room at 23°C and 50% RH for 72 hours before being subjected to measurement. The measurement conditions were as follows. As an evaluation criterion, assuming that the polyamide block copolymer would be used as a coating material, 1.0 x 10 ９ "Y" is defined as Ω·m or greater, 1.0 × 10 ９ A resistance of less than Ω·m was evaluated as "N," "Y" was considered a pass, and "N" was considered a fail. A "Y" rating indicates that the insulation performance is sufficiently high even after water absorption. (Measurement conditions) Equipment: High resistance meter 4339B (manufactured by Agilent Technologies, Inc.) Test room environment: 23℃±2℃, 50%RH±5%RH Applied voltage: 500V DC × 1 min Electrode dimensions: Main electrode diameter 50 mm, annular electrode inner diameter 60 mm Electrode material: Conductive rubber

[0089] <Polymer Block (A)> PA-1 to PA-6, prepared in the following synthesis example, were used as components of polymer block (A). [Synthesis Example 1] Preparation of semi-aromatic polyamide (PA-1) 230.4 g (1.387 mol) of terephthalic acid, 189.9 g (1.200 mol) of a mixture of 1,9-nonanediamine / 2-methyl-1,8-octanediamine (molar ratio 50 / 50), 0.420 g of sodium hypophosphate monohydrate (0.1% by mass relative to the total mass of raw materials), and 180 mL of distilled water were placed in a 1 L autoclave and purged with nitrogen. The mixture was stirred at 150°C for 30 minutes, and the temperature inside the autoclave was raised to 230°C over 1 hour. At this time, the pressure inside the autoclave was raised to 2.0 MPa. The reaction was allowed to proceed while gradually releasing the water vapor, and 157 g of distilled water was removed. After heating for a further 30 minutes, heating and stirring were stopped and the mixture was cooled to obtain a prepolymer. The obtained prepolymer was dried at 120°C under reduced pressure for 24 hours and then pulverized to a particle size of 1 mm or less. This prepolymer is abbreviated as "PA-1".

[0090] [Synthesis Example 2] A prepolymer was obtained using the same procedure as in Synthesis Example 1, except that the raw materials used for the production of semi-aromatic polyamide (PA-2) were replaced with 244.6 g (1.472 mol) of terephthalic acid, 174.1 g (1.100 mol) of a mixture of 1,9-nonanediamine / 2-methyl-1,8-octanediamine (molar ratio 50 / 50), 0.419 g of sodium hypophosphate monohydrate (0.1% by mass relative to the total mass of the raw materials), and 180 mL of distilled water, and 152 g of distilled water was removed. This prepolymer is abbreviated as "PA-2".

[0091] [Synthesis Example 3] A prepolymer was obtained using the same procedure as in Synthesis Example 1, except that the raw materials used for the production of semi-aromatic polyamide (PA-3) were replaced with 252.6 g (1.520 mol) of terephthalic acid, 197.9 g (1.250 mol) of a mixture of 1,9-nonanediamine / 2-methyl-1,8-octanediamine (molar ratio 50 / 50), 0.450 g of sodium hypophosphate monohydrate (0.1% by mass relative to the total mass of the raw materials), and 150 mL of distilled water, and 124 g of distilled water was removed. This prepolymer is abbreviated as "PA-3".

[0092] [Synthesis Example 4] A prepolymer was obtained using the same procedure as in Synthesis Example 1, except that the raw materials used for the production of semi-aromatic polyamide (PA-4) were replaced with 263.8 g (1.588 mol) of terephthalic acid, 186.8 g (1.180 mol) of a mixture of 1,9-nonanediamine / 2-methyl-1,8-octanediamine (molar ratio 85 / 15), 0.451 g of sodium hypophosphate monohydrate (0.1% by mass relative to the total mass of the raw materials), and 150 mL of distilled water, and 121 g of distilled water was removed. This prepolymer is abbreviated as "PA-4".

[0093] [Synthesis Example 5] A prepolymer was obtained using the same procedure as in Synthesis Example 1, except that the raw materials used for the production of semi-aromatic polyamide (PA-5) were replaced with 255.8 g (1.540 mol) terephthalic acid, 194.7 g (1.130 mol) 1,10-decanediamine, 0.451 g of sodium hypophosphate monohydrate (0.1% by mass relative to the total mass of the raw materials), and 150 mL of distilled water, and 119 g of distilled water was removed. This prepolymer is abbreviated as "PA-5".

[0094] [Synthesis Example 6] A prepolymer was obtained using the same procedure as in Synthesis Example 1, except that the raw materials used for the production of semi-aromatic polyamide (PA-6) were replaced with 95.0 g (0.650 mol) of adipic acid, 59.4 g (0.511 mol) of hexamethylenediamine, 0.154 g of sodium hypophosphate monohydrate (0.1% by mass relative to the total mass of the raw materials), and 51.5 mL of distilled water, and 45.9 g of distilled water was removed. This prepolymer is abbreviated as "PA-6".

[0095] Table 1 shows the types of PA-1 to PA-6 and the measurement results of their physical properties.

[0096] <Polymer Block (B)> The following polymer blocks (B) were used: ・D-400: PPG diamine, manufactured by HUNTSMAN, JEFFAMINE (registered trademark, same hereinafter) D Series (D-400) ・RT-1000: PPG / PTMG / PPG triblock diamine, manufactured by HUNTSMAN, JEFFAMINE RT Series (RT-1000) ・PTMGPA1000: Polytetramethylene glycol diamine, manufactured by Koei Chemical Co., Ltd., PTMGPA-1000 ・ED-900: PPG / PEG / PPG triblock diamine, manufactured by HUNTSMAN, JEFFAMINE ED Series (ED-900)

[0097] Table 1 shows the types and measurement results of the physical properties of each polymer block (B).

[0098] <Example 1> In a 200 mL flask equipped with apparatus for distilling off generated volatile components, 73.0 parts by mass (46.9 mmol) of semi-aromatic polyamide (PA-1) as polymer block (A) and 0.5 parts by mass of Irganox 1010 (BASF Japan Ltd.) as an antioxidant were added. The mixture was then heated under a nitrogen stream of 50 mL / min until the temperature of the contents reached 270°C, and maintained at this temperature for 1 hour. Subsequently, 27.0 parts by mass (46.9 mmol) of polyetherdiamine (Huntsman Jeffamine D Series (D-400)) was added as polymer block (B) at a constant rate (20 mol% / h) over 5 hours. After that, the mixture was stirred for 1.5 hours while removing the distillate, and polymerization was further carried out by reducing the pressure to 10 Pa for 30 minutes. Then, the reduced pressure was released, and the reaction product was removed from the flask to obtain the polyamide block copolymer composition according to Example 1.

[0099] <Example 2> A polyamide block copolymer composition according to Example 2 was prepared using the same procedure as in Example 1, except that 68.0 parts by mass of the above-mentioned semi-aromatic polyamide (PA-2) was used as polymer block (A) instead of 73.0 parts by mass of semi-aromatic polyamide (PA-1), and 32.0 parts by mass (6.5 mmol) of polyetherdiamine (JEFFAMINE RT Series (RT-1000) manufactured by HUNTSMAN) was used as polymer block (B) instead of 27.0 parts by mass of D-400.

[0100] <Example 3> A polyamide block copolymer composition according to Example 3 was prepared using the same procedure as in Example 2, except that semi-aromatic polyamide (PA-3) was used instead of semi-aromatic polyamide (PA-2), and the mass ratio (A) / (B) of polymer block (A) to polymer block (B) was changed to the ratio shown in Table 1.

[0101] <Example 4> A polyamide block copolymer composition according to Example 4 was prepared using the same procedure as in Example 2, except that semi-aromatic polyamide (PA-1) was used instead of semi-aromatic polyamide (PA-2), and the mass ratio (A) / (B) of polymer block (A) to polymer block (B) was changed to the ratio shown in Table 1.

[0102] <Example 5> In a 200 mL flask equipped with apparatus for distilling off generated volatile components, 66.0 parts by mass (18.0 mmol) of semi-aromatic polyamide (PA-2) as polymer block (A) and 0.5 parts by mass of Irganox 1010 (manufactured by BASF Japan Ltd.) as an antioxidant were added. The mixture was heated under a nitrogen stream of 50 mL / min until the temperature of the contents reached 270°C, and this temperature was maintained for 1 hour. Subsequently, 34.0 parts by mass (18.0 mmol) of polyetherdiamine (PTMGPA-1000, manufactured by Koei Chemical Co., Ltd.) was added at a constant rate over 5 hours as polymer block (B). After that, the mixture was stirred for 1.5 hours while removing the distillate, and polymerization was further carried out by reducing the pressure to 10 Pa for 30 minutes. The pressure was then released, and the reaction product was removed from the flask to obtain the polyamide block copolymer composition according to Example 5.

[0103] <Example 6> In a 200 mL flask equipped with apparatus for distilling off generated volatile components, 51.0 parts by mass (10.0 mmol) of semi-aromatic polyamide (PA-4) as polymer block (A) and 0.5 parts by mass of Irganox 1010 (manufactured by BASF Japan Ltd.) as an antioxidant were added. The mixture was heated under a nitrogen stream of 50 mL / min until the temperature of the contents reached 290°C, and this temperature was maintained for 1 hour. Subsequently, 49.0 parts by mass (10.0 mmol) of polyetherdiamine (JEFFAMINE RT Series (RT-1000) manufactured by HUNTSMAN) was added at a constant rate over 5 hours as polymer block (B). After that, the mixture was stirred for 1.5 hours while removing the distillate, and polymerization was carried out by reducing the pressure to 10 Pa for 30 minutes. The pressure was then released, and the reaction product was removed from the flask to obtain the polyamide block copolymer composition according to Example 6.

[0104] <Example 7> In a 200 mL flask equipped with apparatus for distilling off generated volatile components, 52.0 parts by mass (10.0 mmol) of semi-aromatic polyamide (PA-5) as polymer block (A) and 0.5 parts by mass of Irganox 1010 (BASF Japan Ltd.) as an antioxidant were added. The mixture was heated under a nitrogen stream of 50 mL / min until the temperature of the contents reached 300°C, and maintained at this temperature for 1 hour. Subsequently, 48.0 parts by mass (10.0 mmol) of polyetherdiamine (Huntsman Jeffamine RT Series (RT-1000)) as polymer block (B) was added at a constant rate over 5 hours. After that, the mixture was stirred for 1.5 hours while removing the distillate, and polymerization was further carried out by reducing the pressure to 10 Pa for 30 minutes. The pressure was then released, and the reaction product was removed from the flask to obtain the polyamide block copolymer composition according to Example 7.

[0105] <Comparative Example 1> In a 500 mL flask equipped with apparatus for distilling off generated volatile components, 68.0 parts by mass of semi-aromatic polyamide (PA-2) as polymer block (A) and 0.5 parts by mass of Irganox 1010 (manufactured by BASF Japan Ltd.) as an antioxidant were added. The mixture was then heated under a nitrogen stream of 50 mL / min until the temperature of the contents reached 270°C, and maintained at this temperature for 1 hour. Subsequently, 32.0 parts by mass of the above-mentioned polyetherdiamine RT-1000 was added all at once as polymer block (B). After that, the mixture was stirred for 1.5 hours while removing the distillate, and polymerization was carried out by reducing the pressure to 10 Pa for 30 minutes. The pressure was then released, and the reaction product was removed from the flask to obtain the polyamide block copolymer composition according to Comparative Example 1.

[0106] <Comparative Example 2> A polyamide block copolymer composition according to Comparative Example 2 was prepared using the same procedure as in Comparative Example 1, except that 33.0 parts by mass of ED-900 were used instead of 32.0 parts by mass of RT-1000 as polymer block (B).

[0107] <Comparative Example 3> A polyamide block copolymer composition according to Comparative Example 3 was prepared using the same procedure as in Example 1, except that 39.0 parts by mass of the above-mentioned semi-aromatic polyamide (PA-6) was used as polymer block (A) instead of 73.0 parts by mass of semi-aromatic polyamide (PA-1), and 61.0 parts by mass of the above-mentioned RT-1000 was used as polymer block (B) instead of 27.0 parts by mass of D-400.

[0108] The polyamide block copolymer compositions obtained in the above examples and comparative examples were used to evaluate various physical properties. The results of the physical property evaluation are shown in Table 1. The notation in Table 1 is as follows: "9T" is polynonameethylene terephthalamide (polyamide 9T). "10T" is polydecamethylene terephthalamide (polyamide 10T). "66" is polyhexamethylene adipamide (polyamide 66). "D-400" is JEFFAMINE D Series (D-400) manufactured by HUNTSMAN. "RT-1000" is JEFFAMINE RT Series (RT-1000) manufactured by HUNTSMAN. "PTMGPA-1000" is PTMGPA-1000 manufactured by Koei Chemical Co., Ltd. "ED-900" refers to the JEFFAMINE ED Series (ED-900) manufactured by HUNTSMAN. "n / i" indicates the molar ratio of linear diamine units to branched diamine units.

[0109] Furthermore, Figure 1 shows a graph illustrating the relationship between the tensile elongation at break TE and the tensile modulus TM of the polyamide block copolymer compositions of the above examples and comparative examples. In Figure 1, the straight line represents TE = 400 - TM / 9. Also, symbols E1 to E7 correspond to Examples 1 to 7, and symbols C1 to C3 correspond to Comparative Examples 1 to 3.

[0110]

[0111] As is clear from the results in Table 1, the polyamide block copolymer compositions obtained in Examples 1 to 7 possessed high heat resistance and mechanical properties, as well as excellent dimensional stability and insulation properties when water was absorbed.

[0112] On the other hand, as shown in Figure 1, the polyamide block copolymer composition of Comparative Example 1 did not satisfy the relationship of formula (1) for tensile elongation at break TE and tensile modulus TM. Although the dimensional change rate during water absorption was small, the bending recovery at high temperatures was significantly inferior to that of the polyamide block copolymer composition of Example. From a comparison between Example 2 and Comparative Example 1, it can be understood that when preparing the polyamide block copolymer composition, it is important to add the second polymer for polymer block (B) to the molten first polymer for polymer block (A) in small amounts to obtain the above-mentioned technical effects. Therefore, simply mixing the polymer for polymer block (A) and the polymer for polymer block (B) without considering the addition of the second polymer for polymer block (B) in small amounts is undesirable, at least from the viewpoint of bending recovery at high temperatures.

[0113] Furthermore, although the polyamide block copolymer compositions of Comparative Examples 2 and 3 satisfied the relationship between the tensile elongation at break TE and the tensile modulus TM of formula (1), their high water absorption rate resulted in a large dimensional change rate during water absorption, and their insulation properties did not reach an acceptable level.

[0114] The polyamide block copolymer obtained by the reaction of polymer block (A) and polymer block (B) according to this embodiment possesses high heat resistance and mechanical properties, as well as excellent dimensional stability and insulation properties when water is absorbed. Therefore, the polyamide block copolymer and polyamide block copolymer composition according to this embodiment can be widely used as materials for various components, such as electrical and electronic components, automobile parts, industrial materials, industrial parts, daily necessities, household goods, sports equipment, leisure equipment, and medical equipment. In particular, it can be applied as complex-shaped parts by injection molding, hollow molded parts by blow molding, coating materials by extrusion molding, hose and tube-shaped parts, films and sheets, lightweight members and heat insulating materials by at least one of injection molding and extrusion foam molding, and as additives for resin modification. This application is based on Japanese Patent Application No. 2025-005954 filed on January 16, 2025, which is incorporated herein by reference in its entirety.

[0115] E1: Shows the measurement results of the tensile elongation at break TE and tensile modulus TM for Example 1. E2: Shows the measurement results of the tensile elongation at break TE and tensile modulus TM for Example 2. E3: Shows the measurement results of the tensile elongation at break TE and tensile modulus TM for Example 3. E4: Shows the measurement results of the tensile elongation at break TE and tensile modulus TM for Example 4. E5: Shows the measurement results of the tensile elongation at break TE and tensile modulus TM for Example 5. E6: Shows the measurement results of the tensile elongation at break TE and tensile modulus TM for Example 6. E7: Shows the measurement results of the tensile elongation at break TE and tensile modulus TM for Example 7. C1: Shows the measurement results of the tensile elongation at break TE and tensile modulus TM for Comparative Example 1. C2: Shows the measurement results of the tensile elongation at break TE and tensile modulus TM for Comparative Example 2. C3: Shows the measurement results of the tensile elongation at break TE and tensile modulus TM for Comparative Example 3.

Claims

1. A polyamide block copolymer comprising a polymer block (A) containing 50 mol% or more of polyamide-derived structural units and having a glass transition temperature greater than 20°C, and a polymer block (B) having a glass transition temperature of 20°C or less, satisfying the following conditions (i) to (iii): (i) The melting point of the polyamide block copolymer is 190°C or higher. (ii) The water absorption rate of the polyamide block copolymer is 5.0% or less. (iii) The tensile elongation at break TE (%) and tensile modulus TM (MPa) of the polyamide block copolymer, measured in accordance with JIS K 7161-1:2014, satisfy the following relationship (1): TE > 400 - TM / 9 ... Equation (1) 2. The polyamide block copolymer according to claim 1, wherein the polyamide comprises a structural unit derived from at least one aliphatic diamine selected from the group consisting of linear aliphatic diamines and branched aliphatic diamines.

3. The polyamide block copolymer according to claim 2, wherein the polyamide comprises diamine units mainly composed of structural units derived from the aliphatic diamine and dicarboxylic acid units mainly composed of structural units derived from an aromatic dicarboxylic acid.

4. The polyamide block copolymer according to claim 1, wherein the polyamide comprises a structural unit derived from at least one selected from the group consisting of 1,9-nonanediamine and 2-methyl-1,8-octanediamine.

5. The polyamide block copolymer according to claim 1, wherein the polyamide comprises a constituent unit derived from at least one selected from the group consisting of terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid.

6. The polyamide block copolymer according to claim 1, wherein the polymer block (B) comprises a constituent unit selected from the group consisting of polyether polyols, polyester polyols, polycarbonate polyols, polysiloxane polyols, and their amine derivatives and their carboxyl derivatives.

7. The polyamide block copolymer according to claim 1, wherein the polymer block (B) comprises a constituent unit derived from polyether polyols, polyester polyols, polycarbonate polyols, and at least one selected from the group consisting of amine derivatives and carboxyl derivatives thereof, each comprising a constituent unit derived from a hydrocarbon having 3 to 9 carbon atoms.

8. The polyamide block copolymer according to claim 1, wherein the polymer block (B) comprises a structural unit derived from at least one selected from the group consisting of a polyether polyol containing a structural unit derived from an alkylene glycol having 3 to 4 carbon atoms, an amine derivative of the polyether polyol, and a carboxyl derivative of the polyether polyol.

9. The polyamide block copolymer according to claim 1, wherein the tensile elongation TE of the polyamide block copolymer is 30% or more.

10. The polyamide block copolymer according to claim 1, wherein the tensile modulus™ of the polyamide block copolymer is 100 MPa or more and 2,500 MPa or less.

11. The polyamide block copolymer according to claim 1, wherein the number average molecular weight Mn of the polyamide block copolymer is 20,000 or more and 500,000 or less.

12. The polyamide block copolymer according to claim 1, wherein the molecular weight distribution (weight-average molecular weight Mw / number-average molecular weight Mn) of the polyamide block copolymer is 1.0 to 5.

0.

13. A polyamide block copolymer composition comprising the polyamide block copolymer described in any one of claims 1 to 12.

14. A molded article comprising a polyamide block copolymer according to any one of claims 1 to 12.

15. A coating material comprising the polyamide block copolymer according to any one of claims 1 to 12.

16. An electric wire comprising the covering material described in claim 15.

17. A bus bar comprising the covering material described in claim 15.

18. A cable comprising the covering material described in claim 15.

19. A tube comprising the polyamide block copolymer according to any one of claims 1 to 12.

20. A hose comprising the polyamide block copolymer according to any one of claims 1 to 12.

21. A method for producing a polyamide block copolymer according to any one of claims 1 to 12, wherein the total amount of the second polymer constituting a polymer block (B) to be added to a first polymer constituting a polymer block (A) is 100 mol%, and the second polymer is added to the molten first polymer at an addition rate of 20 mol% / h or less.

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