Polyamide block copolymer, polyamide block copolymer composition, and molded body

Abstract

Disclosed is a polyamide block copolymer which comprises: a polymer block (A) that 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 polymer block (A) contains 50 mol% or more of a constitutional unit that is derived from a semiaromatic polyamide. The polyamide block copolymer has a complex shear viscosity η0 of 500-10,000 (Pa∙s) at an angular frequency of 6.28 rad∙s- 1 and a strain hardening parameter H of 1.5 or more.

Description

Polyamide block copolymer, polyamide block copolymer composition, and molded article

[0001] The present invention relates to a polyamide block copolymer, a polyamide block copolymer composition, and a molded article.

[0002] Polyamide block copolymers have excellent physical properties, such as heat resistance, chemical resistance, and mechanical strength, and are therefore used in a wide range of fields, including automotive interior and exterior components, electronic device components, and sporting goods. While polyamide block copolymers have a certain degree of moldability, they generally tend to have low melt viscosity. As a result, polyamide block copolymers may experience cell breakage during foam molding, resulting in a decrease in expansion ratio and strength. Furthermore, polyamide block copolymers may cause thickness deviation due to drawdown during blow molding. Therefore, methods have been proposed for improving foam moldability and blow moldability by introducing branching or crosslinking into the molecular chain of polyamide block copolymers (e.g., Patent Documents 1 and 2).

[0003] Patent Document 1 discloses a branched aliphatic polyamide block copolymer in which a branched structure is imparted by a polyol containing three or more hydroxy groups that is bonded to hard segments, with the aim of improving foamability in foam molding.

[0004] Patent Document 2 discloses a cross-linked aliphatic polyamide block copolymer having a structure in which a polyalkylene glycol soft segment is bonded to a cross-linking agent, with the aim of improving the physical properties of the foam.

[0005] JP 2022-525206 A Publication No. WO 2023 / 074726

[0006] Patent Documents 1 and 2 propose techniques for improving the moldability of polyamide block copolymers. However, polyamide block copolymers are required to have even higher performance depending on their applications. In particular, polyamide block copolymers that have an excellent balance between heat resistance and moldability are still desired.

[0007] Therefore, an object of the present invention is to provide a polyamide block copolymer, a polyamide block copolymer composition, and a molded article that have an excellent balance between heat resistance and moldability.

[0008] As a result of intensive research to solve the above problems, the present inventors have conceived the following invention and found that the above problems can be solved.

[0009] [1] A polyamide block copolymer comprising a polymer block (A) having a glass transition temperature of more than 20°C and a polymer block (B) having a glass transition temperature of 20°C or less, wherein the polymer block (A) contains 50 mol% or more of structural units derived from a semi-aromatic polyamide, and the polyamide block copolymer is characterized in that a first test piece of the polyamide block copolymer is measured using a parallel plate oscillatory rheometer in accordance with JIS K7244-10:2005 at a temperature 30°C higher than the melting point and an angular frequency of 0.0628 to 628 rad·s －１ The complex shear viscosity η0 measured while changing in a logarithmic sweep up to an angular frequency of 6.28 rad s －１and a strain hardening parameter H, which indicates the ratio of a first viscosity η1 to a second viscosity η2, as expressed by the following formula (1): H=η1 / η2 (1) (in the formula (1), the first viscosity η1 is the maximum attainable elongational viscosity (Pa s) obtained when an elongation test is performed along the long side direction on a second test piece of the polyamide block copolymer having a thickness of 0.8 mm, long sides of 20 mm, and short sides of 10 mm, at a temperature 10°C higher than the melting point and at a strain rate of 1.0 / s; and the second viscosity η2 is three times the viscosity value (Pa s) obtained when the elongation time t1 (s) at which the maximum attainable elongational viscosity η1 is exhibited is substituted for time t in a shear viscosity growth function η(t) when the polyamide block copolymer exhibits linear viscoelasticity). [2] The polyamide block copolymer according to [1], wherein the strain hardening parameter H is 3.0 or greater. [3] The polyamide block copolymer according to [1] or [2], wherein the polymer block (B) is selected from structural units derived from polyether polyols, polyester polyols, polycarbonate polyols, polysiloxane polyols, or amine derivatives or carboxyl derivatives thereof, and combinations thereof. [4] The polyamide block copolymer according to any of [1] to [3], wherein the polymer block (A) and the polymer block (B) are bonded directly or indirectly via an amide bond. [5] The polyamide block copolymer according to any of [1] to [4], wherein the polyamide block copolymer is a branched polymer. [6] The polyamide block copolymer according to any of [1] to [5], wherein the polyamide block copolymer contains a linking group (C) that indirectly bonds the polymer block (A) and the polymer block (B), and the linking group (C) contains a structural unit (C-1) derived from a polymerizable monomer (c1) having three or more reactive functional groups. [7] The polyamide block copolymer according to [6], wherein the polymerizable monomer (c1) is a polyamine having three or more amino groups. [8] The polyamide block copolymer according to [7], wherein the polyamine has a polyether structure as a repeating unit in its main chain.[9] The polyamide block copolymer according to any one of [6] to [8], wherein the linking group (C) includes a structural unit (C-2) derived from a bifunctional polymerizable monomer (c2).

[10] The polyamide block copolymer according to any one of [1] to [9], wherein the strain hardening parameter H is 50 or less.

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

[10] .

[12] A molded article comprising the polyamide block copolymer according to any one of [1] to

[10] or the polyamide block copolymer composition according to

[11] .

[13] The molded article according to

[12] , which is a foam.

[0010] According to the present invention, it is possible to provide a polyamide block copolymer, a polyamide block copolymer composition, and a molded article that are excellent in balance between heat resistance and moldability.

[0011] FIG. 1 is a diagram schematically showing the relationship between extension time and extensional viscosity (solid line) when a test piece of a polyamide block copolymer is elongated, and a linear viscosity growth curve (dashed line).

[0012] The following describes an embodiment of the present invention. However, the embodiment described below is merely an example for embodying the technical concept of the present invention, and the present invention is not limited to the following description. Furthermore, although preferred embodiments are shown in this specification, a combination of two or more of the individual preferred embodiments is also a preferred embodiment. For matters indicated as numerical ranges, when there are several numerical ranges, the lower and upper limits can be selectively combined to form a preferred embodiment. Note that, in this specification, a numerical range such as "XX to YY" means "XX or more and YY or less." Furthermore, in this specification, the term "unit" (where "~" indicates a monomer) means "a structural unit derived from ~." For example, "dicarboxylic acid unit" means "a structural unit derived from dicarboxylic acid," and "diamine unit" means "a structural unit derived from diamine."

[0013] <Polyamide Block Copolymer> The polyamide block copolymer of this embodiment is a polyamide block copolymer including a polymer block (A) having a glass transition temperature of more than 20°C and a polymer block (B) having a glass transition temperature of 20°C or less, wherein the polymer block (A) contains 50 mol% or more of structural units derived from a semi-aromatic polyamide, and the polyamide block copolymer has an angular frequency of 6.28 rad s measured under the conditions described below. －１ The polyamide block copolymer has a complex shear viscosity η0 of 500 to 10,000 [Pa s] and a strain hardening parameter H (described later) of 3.0 or more. The polymer constituting polymer block (A) is usually bifunctional. The polymer constituting polymer block (B) is usually bifunctional.

[0014] The polyamide block copolymer of this embodiment has excellent heat resistance because the polymer block (A) contains a semi-aromatic polyamide. In addition, the polyamide block copolymer exhibits strain hardening at a certain level or higher in a molten state and has a melt viscosity at a certain level or higher, and therefore has excellent molding processability such as foam molding, extrusion molding, blow molding, and melt spinning.

[0015] In the polyamide block copolymer of this embodiment, the difference in glass transition temperature between polymer block (A) and polymer block (B) (glass transition temperature of polymer block (A) - glass transition temperature of polymer block (A) (B)) is preferably 20°C or higher, more preferably 50°C or higher, even more preferably 100°C or higher, and still more preferably 150°C or higher, from the viewpoint of obtaining a polyamide block copolymer having an excellent balance between heat resistance and moldability.

[0016] <Polymer Block (A)> The polymer block (A) contained in the block copolymer according to this embodiment has a glass transition temperature of more than 20°C. The glass transition temperature of the polymer block (A) usually refers to the glass transition temperature of the polymer constituting the polymer block (A). Specifically, the glass transition temperature of the polymer block (A) can be measured by the method described in the Examples section below.

[0017] Furthermore, polymer block (A) contains 50 mol% or more of structural units derived from a semi-aromatic polyamide. From the viewpoint of easily obtaining even better heat resistance, polymer block (A) contains preferably 70 mol% or more, more preferably 90 mol% or more, and may contain 100 mol% of structural units derived from a semi-aromatic polyamide. In polymer block (A), structural units other than the structural units derived from a semi-aromatic polyamide are not limited as long as the effects of the present invention can be obtained.

[0018] Semi-aromatic polyamides that can be suitably used in this embodiment will be described in detail below.

[0019] <Semi-aromatic Polyamide> Semi-aromatic polyamide refers to a polyamide containing diamine units primarily composed of aliphatic diamine units and dicarboxylic acid units primarily composed of aromatic dicarboxylic acid units, or a polyamide resin containing dicarboxylic acid units primarily composed of aliphatic dicarboxylic acid units and diamine units primarily composed of aromatic diamine units. Here, "primarily composed" refers to constituting 50 to 100 mol%, preferably 60 to 100 mol%, of all units. In this embodiment, from the viewpoint of superior heat resistance, the semi-aromatic polyamide preferably contains diamine units primarily composed of aliphatic diamine units and dicarboxylic acid units primarily composed of aromatic dicarboxylic acid units.

[0020] (Melting Point of Semi-Aromatic Polyamide) In one embodiment, the glass transition temperature of the semi-aromatic polyamide is 80 to 160°C. From the viewpoint of heat resistance, it is preferably 90°C or higher, more preferably 100°C or higher, and even more preferably 110°C or higher. Here, it is generally known that the glass transition temperature (K) of a crystalline resin is about 2 / 3 of its melting point (K). Therefore, although there is no upper limit for the glass transition temperature of the semi-aromatic polyamide, the glass transition temperature of the semi-aromatic polyamide is usually about 2 / 3 of its melting point (K). From the viewpoint of moldability, the glass transition temperature of the semi-aromatic polyamide is preferably 150°C or lower. Specifically, the glass transition temperature can be measured by the method described in the Examples section below.

[0021] [Aliphatic diamine unit] From the viewpoint of achieving both mechanical properties and heat resistance, the aliphatic diamine used in the aliphatic diamine unit is preferably an aliphatic diamine having 4 to 18 carbon atoms, more preferably an aliphatic diamine having 4 to 16 carbon atoms, even more preferably an aliphatic diamine having 4 to 12 carbon atoms, still more preferably an aliphatic diamine having 6 to 12 carbon atoms, still more preferably an aliphatic diamine having 6 to 10 carbon atoms, and even more preferably an aliphatic diamine having 7 to 10 carbon atoms.

[0022] 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 amine, 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 nonanediamine, 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;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; and the like. Among these, from the viewpoints of more significantly achieving the effects of the present invention and excellent raw material availability, the aliphatic diamines are preferably 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 1,6-hexanediamine, 1,9-nonanediamine, 2-methyl-1,8-octanediamine, and 1,10-decanediamine, and even more preferably 1,9-nonanediamine and 2-methyl-1,8-octanediamine. These may be used alone or in combination of two or more.

[0023] From the viewpoint that the polymerization reaction with dicarboxylic acid proceeds smoothly and is advantageous in improving physical properties such as heat resistance and flexibility, the content of structural units derived from aliphatic diamines having 4 to 18 carbon atoms relative to all diamine 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 even be 100 mol%.

[0024] From the viewpoint of heat resistance, it is preferable to use, as the aliphatic diamine, at least one selected from the group consisting of linear aliphatic diamines and branched aliphatic diamines, and it is more preferable to use a linear aliphatic diamine and a branched aliphatic diamine in combination.

[0025] When a linear aliphatic diamine and a branched aliphatic diamine are used in combination, the molar ratio of linear aliphatic diamine to branched aliphatic diamine is preferably 99:1 to 1:99, more preferably 95:5 to 5:95, even more preferably 90:10 to 10:90, and even more preferably 85:15 to 15:85, and the above molar ratio may also be 80:20 to 20:80, 70:30 to 30:70, or 65:35 to 35:65. When the molar ratio of linear aliphatic diamine to branched aliphatic diamine is within the above range, the resulting polyamide block copolymer can be expected to have excellent heat resistance and flexibility.

[0026] From the viewpoints of achieving the effects of the present invention more significantly and having excellent raw material availability, the linear aliphatic diamine is preferably 1,4-butanediamine, 1,6-hexanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, or 1,12-dodecanediamine, and more preferably 1,6-hexanediamine, 1,9-nonanediamine, or 1,10-decanediamine. Furthermore, the branched aliphatic diamine is preferably 2-propyl-1,6-hexanediamine, 2-ethyl-1,7-heptanediamine, or 2-methyl-1,8-octanediamine, and more preferably 2-methyl-1,8-octanediamine. Among these, it is more preferable that the semi-aromatic polyamide contains structural units derived from both 1,9-nonanediamine and 2-methyl-1,8-octanediamine, or contains structural units derived from both 1,6-hexanediamine and 1,10-decanediamine, and from the viewpoint of easily obtaining moldability and even more excellent heat resistance, it is even more preferable that the semi-aromatic polyamide contains structural units derived from both 1,9-nonanediamine and 2-methyl-1,8-octanediamine.

[0027] When 1,9-nonanediamine and 2-methyl-1,8-octanediamine are used in combination, the content of 1,9-nonanediamine units and / or 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 1,9-nonanediamine units and / or 2-methyl-1,8-octanediamine units in the total amount of diamine units constituting the semi-aromatic polyamide is within the above range, further improved heat resistance and excellent chemical resistance can also be expected.

[0028] When 1,9-nonanediamine and 2-methyl-1,8-octanediamine are used in combination, the molar ratio of 1,9-nonanediamine: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, and even more preferably 85:15 to 15:85. Alternatively, the molar ratio may be 80:20 to 20:80, 70:30 to 30:70, or 65:35 to 35:65. When the molar ratio of 1,9-nonanediamine to 2-methyl-1,8-octanediamine is within the above range, the resulting polyamide block copolymer can be expected to have excellent heat resistance and flexibility.

[0029] When 1,6-hexanediamine and 1,10-decanediamine are used in combination, the content of 1,6-hexanediamine units and / or 1,10-decanediamine 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 1,6-hexanediamine units and / or 1,10-decanediamine units in the total amount of diamine units constituting the semi-aromatic polyamide is within the above range, further improved heat resistance and excellent chemical resistance can also be expected.

[0030] When 1,6-hexanediamine and 1,10-decanediamine are used in combination, the molar ratio of 1,6-hexanediamine:1,10-decanediamine is preferably 99:1 to 1:99, more preferably 95:5 to 5:95, even more preferably 90:10 to 10:90, and even more preferably 85:15 to 15:85. When the molar ratio of 1,6-hexanediamine to 1,10-decanediamine is within the above range, the resulting polyamide block copolymer can be expected to have both excellent heat resistance and moldability.

[0031] Furthermore, the semi-aromatic polyamide may contain, as diamine units, structural units derived from diamines other than aliphatic diamines, such as aromatic diamines, as long as the effects of the present invention are not impaired. These structural units derived from diamines other than aliphatic diamines may be contained in one type only, or in two or more types. The content of the structural units derived from diamines other than 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.

[0032] [Aromatic Dicarboxylic Acid Unit] Examples of aromatic dicarboxylic acids used in the aromatic dicarboxylic acid unit include 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, and diphenylsulfone-4,4'-dicarboxylic acid. From the viewpoints of smoothly proceeding the polymerization reaction with diamine and advantageously improving physical properties such as heat resistance, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid are preferred, and from the viewpoint of further improving heat resistance, terephthalic acid and 2,6-naphthalenedicarboxylic acid are more preferred. These aromatic dicarboxylic acids may be used alone or in combination of two or more.

[0033] From the viewpoint of heat resistance and mechanical strength, the content of structural units derived from at least one aromatic dicarboxylic acid selected from the group consisting of terephthalic acid and 2,6-naphthalenedicarboxylic acid relative to all dicarboxylic acid units is preferably 30 mol% or more, more preferably 30 to 100 mol%, even more preferably 50 to 100 mol%, still more preferably 70 to 100 mol%, still more preferably 90 to 100 mol%, and may even be 100 mol%.

[0034] Furthermore, the semi-aromatic polyamide may contain, as dicarboxylic acid units, structural units derived from dicarboxylic acids other than aromatic dicarboxylic acids, such as aliphatic dicarboxylic acids, as long as the effects of the present invention are not impaired. These structural units derived from dicarboxylic acids other than aromatic dicarboxylic acids may be contained alone or in combination of two or more. Examples of structural units derived from aliphatic dicarboxylic acids include structural units derived from 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, and dodecanedicarboxylic acid; branched aliphatic dicarboxylic acids such as 2,2-diethylsuccinic acid, 2,2-dimethylglutaric acid, 2-methyladipic acid, and trimethyladipic acid; and structural units derived from alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid. The content of structural units derived from other than the aromatic dicarboxylic acid in the dicarboxylic acid 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.

[0035] (Aliphatic diamine unit and aromatic dicarboxylic acid content) The content of aliphatic diamine-derived structural units relative to all structural units constituting the semi-aromatic polyamide is preferably 15 to 55 mol%, more preferably 25 to 55 mol%, from the viewpoint of heat resistance and chemical resistance. The content of aromatic dicarboxylic acid-derived structural units relative to all structural units constituting the semi-aromatic polyamide is preferably 15 to 55 mol%, more preferably 25 to 55 mol%, from the viewpoint of heat resistance and mechanical strength. The total content of aliphatic diamine and aromatic dicarboxylic acid-derived structural units relative to all structural units constituting 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 also be 90 to 100 mol%, or even 100 mol%, from the viewpoint of heat resistance and moldability.

[0036] [Other Structural Units] The semi-aromatic polyamide may contain other structural units in addition to diamine units and dicarboxylic acid units, as long as the effects of the present invention are not impaired. Examples of other structural units include aminocarboxylic acid units and lactam units. Examples of aminocarboxylic acid units include structural units derived from lactams such as caprolactam and lauryllactam; and aminocarboxylic acids such as 11-aminoundecanoic acid and 12-aminododecanoic acid. Examples of lactam units include structural units derived from ε-caprolactam, enantholactam, undecanelactam, lauryllactam, α-pyrrolidone, and α-piperidone. The content of other structural units relative to all structural units constituting the semi-aromatic polyamide is preferably 30 mol% or less, more preferably 10 mol% or less.

[0037] [Specific Examples of Semi-Aromatic Polyamides] 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), polyhexamethylene terephthalamide / polypentamethylene terephthalamide copolymer (polyamide 6T / 5T), polyhexamethylene terephthalamide / poly(2-methylpentamethyl terephthalamide) ... Poly(2-methyloctamethylene) terephthalamide copolymer (Polyamide 6T / M5T), Polynonamethylene terephthalamide (Polyamide 9T), Poly(2-methyloctamethylene) terephthalamide (Polyamide M8T), Polynonamethylene terephthalamide / Poly(2-methyloctamethylene) terephthalamide copolymer (Polyamide 9T / M8T), Polynonamethylene naphthalene dicarboxamide (Polyamide 9N), Poly(2-methyloctamethylene) naphthalene dicarboxamide (Polyamide M8N), Polynonamethylene naphthalene Dicarboxamide / poly(2-methyloctamethylene)naphthalenedicarboxamide copolymer (Polyamide 9N / M8N), polydecamethylene terephthalamide (Polyamide 10T), polydecamethylene terephthalamide / polypentamethylene terephthalamide copolymer (Polyamide 10T / 5T), polydecamethylene terephthalamide / poly(2-methylpentamethylene) terephthalamide copolymer (Polyamide 10T / M5T), polydecamethylene terephthalamide / poly(2-methyloctamethylene) terephthalamide Phthalamide copolymer (polyamide 10T / M8T), polyhexamethylene isophthalamide (polyamide 6I), copolymer of polyamide 6I and polyamide 6T (polyamide 6I / 6T), copolymer of polyhexamethylene adipamide (polyamide 66) and polyamide 6T (polyamide 66 / polyamide 6T), copolymer of polyamide 66, polyamide 6I and polyamide 6T (polyamide 66 / polyamide 6I / 6T), copolymer of polyamide 6T and polycaprolactam (polyamide 6) (polyamide 6T / 6),Examples include a copolymer of polyamide 6T and polyundecaneamide (polyamide 11) (polyamide 6T / 11), a copolymer of polyamide 6T and polydodecanamide (polyamide 12) (polyamide 6T / 12), polydecamethylene isophthalamide (polyamide 10I), a copolymer of polyamide 10I and polyamide 10T (polyamide 10I / 10T), a copolymer of polyamide 6T and polyamide 10T (polyamide 6T / 10T), a copolymer of polyamide 10T and polyamide 6 (polyamide 10T / 6), a copolymer of polyamide 10T and polyamide 11 (polyamide 10T / 11), and a copolymer of polyamide 10T and polyamide 12 (polyamide 10T / 12).

[0038] [Other Components of Polymer Block (A)] In this embodiment, the polymer block (A) may contain less than 50 mol % of components other than the semi-aromatic polyamide, or may contain no components other than the semi-aromatic polyamide, as long as the effects of the present invention are not impaired. Examples of the components other than the semi-aromatic polyamide include aliphatic polyamides, polyesters having a glass transition temperature of more than 20° C., polyurethanes, etc.

[0039] [End-capping agent] In this embodiment, in order to improve the molecular weight stability of the polyamide block copolymer when melted, the polymer block (A), preferably the semi-aromatic polyamide contained in the polymer block (A), may or may not contain structural units derived from an end-capping agent.

[0040] When the polymer block (A) contains a structural unit derived from a terminal blocking agent, the content of the structural unit derived from the terminal blocking agent is preferably 0 mol % or more and 10 mol % or less, more preferably more than 0 mol % and 10 mol % or less, even more preferably 1.0 to 10 mol %, still more preferably 2.0 to 7.5 mol %, and even more preferably 2.5 to 6.5 mol %, relative to the diamine units in the polymer block (A).

[0041] The content of the structural units derived from the terminal blocking agent can be adjusted by the amount of terminal blocking agent charged relative to the diamine when charging the polymerization raw materials. Taking into consideration the volatilization of the monomer components during polymerization, it is desirable to finely adjust the amount of terminal blocking agent charged when charging the polymerization raw materials so that the desired amount of structural units derived from the terminal blocking agent is introduced into the resulting semi-aromatic polyamide. Furthermore, when polymerizing the polymer for polymer block (A) and the polymer for polymer block (B) together with other polymerizable monomers, the terminal blocking agent can also be charged so that the content falls within the desired range. Furthermore, the terminal blocking agent can also be charged to the polymer for polymer block (A) together with the terminal functionalizing agent described below so that the content falls within the desired range.

[0042] As a method for determining the content of structural units derived from an end-capping agent in a polyamide block copolymer, as shown in Japanese Patent No. 3242781, １ One example of such a method is to measure the integral ratio of signals derived from each terminal group using H-NMR, and determine the content of structural units derived from the terminal blocking agent from this ratio.

[0043] As the terminal blocking agent, a monofunctional compound reactive with a terminal amino group or a terminal carboxyl group can be used. Specific examples include monocarboxylic acids, acid anhydrides, monoisocyanates, monoacid halides, monoesters, monoalcohols, and monoamines. From the viewpoints of reactivity and the stability of the blocked terminals, monocarboxylic acids are preferred as terminal blocking agents for terminal amino groups, and monoamines are preferred as terminal blocking agents for terminal carboxyl groups. From the viewpoints of ease of handling, monocarboxylic acids are more preferred as terminal blocking agents.

[0044] The monocarboxylic acid used as the terminal blocking agent is not particularly limited as long as it is reactive with an amino group. Examples of the monocarboxylic acid include aliphatic monocarboxylic acids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, decanoic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, behenic acid, pivalic acid, and isobutyric acid; alicyclic monocarboxylic acids such as cyclopentanecarboxylic acid and cyclohexanecarboxylic acid; aromatic monocarboxylic acids such as benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, and methylnaphthalenecarboxylic acid; monocarboxylic acids having an aromatic alkyl group such as phenylacetic acid; and mixtures thereof. Among these, at least one selected from acetic acid, propionic acid, butyric acid, decanoic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, stearic acid, and benzoic acid is preferred in terms of reactivity, stability of the blocked terminal, cost, and the like.

[0045] The monoamine used as the terminal blocking agent is not particularly limited as long as it is reactive with a carboxyl group. Examples of the monoamine include aliphatic monoamines such as methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, dodecylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, and dibutylamine; alicyclic monoamines such as cyclohexylamine and dicyclohexylamine; aromatic monoamines such as aniline, toluidine, diphenylamine, and naphthylamine; and any mixtures thereof. Among these, at least one selected from methylamine, ethylamine, propylamine, dodecylamine, stearylamine, cyclohexylamine, and aniline is preferred in terms of reactivity, high boiling point, stability of the blocked terminal, and cost.

[0046] [Method for Producing Semi-Aromatic Polyamide] The semi-aromatic polyamide contained in the polymer block (A) can be produced, for example, from dicarboxylic acid and diamine as raw materials by a method such as melt polymerization, solid-state polymerization, melt extrusion polymerization, etc. Specifically, the semi-aromatic polyamide can be produced as follows.

[0047] First, a diamine, a dicarboxylic acid, and optionally an aminocarboxylic acid, a lactam, a catalyst, an end-capping agent, etc. are mixed to produce a nylon salt. Next, the resulting nylon salt is heated to a temperature of 200 to 250°C and thermally polymerized to produce a low-molecular-weight prepolymer. Furthermore, the prepolymer can be solid-phase polymerized or polymerized using a melt extruder to achieve a high degree of polymerization, thereby adjusting the molecular weight of the semi-aromatic polyamide to the desired level.

[0048] When the high polymerization degree stage is carried out by solid-state polymerization, it is preferably carried out under reduced pressure or in an inert gas flow, and the polymerization rate is high, productivity is excellent, and coloration and gelation can be effectively suppressed so long as the polymerization temperature is within the range of 200 to 280° C. Furthermore, when the high polymerization degree stage is carried out using a melt extruder, the polymerization temperature is preferably 370° C. or less, and polymerization under such conditions results in a semi-aromatic polyamide with almost no decomposition and little deterioration.

[0049] Examples of catalysts that can be used in producing semi-aromatic polyamides include phosphoric acid, phosphorous acid, hypophosphorous acid, and salts or esters thereof. Examples of the 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, and antimony; ammonium salts of phosphoric acid, phosphorous acid, or hypophosphorous acid; and ethyl esters, isopropyl esters, butyl esters, hexyl esters, isodecyl esters, octadecyl esters, decyl esters, stearyl esters, and phenyl esters of phosphoric acid, phosphorous acid, or hypophosphorous acid. The lower limit of the catalyst usage 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 raw materials used in producing semi-aromatic polyamides. The upper limit of the catalyst usage is preferably 1.0% by mass or less, more preferably 0.5% by mass or less. Polymerization proceeds more smoothly when the catalyst usage amount is within the above range.

[0050] [Melting Point of Semi-Aromatic Polyamide] The melting point of the semi-aromatic polyamide is preferably 120°C or higher, more preferably 180°C or higher, even more preferably 230°C or higher, even more preferably 240°C or higher, and even more preferably 250°C or higher. When the melting point of the semi-aromatic polyamide is 120°C or higher, the heat resistance and mechanical properties of the polyamide block copolymer tend to be good. Furthermore, when the melting point of the polyamide is 230°C or higher, the heat resistance of the polyamide block copolymer is easily further improved. There is no particular upper limit for the melting point of the semi-aromatic polyamide, but from the viewpoint of moldability, etc., it is preferably 320°C or lower, more preferably 290°C, and even more preferably 270°C. That is, the melting point of the semi-aromatic polyamide is preferably 120 to 320°C, more preferably 180 to 290°C, and even more preferably 230 to 270°C. In the present invention, the melting point can be determined as the peak temperature of the melting peak that appears when the temperature is increased at a rate of 10°C / min using a differential scanning calorimetry (DSC) analyzer. More specifically, it can be determined by the method described in the Examples below.

[0051] [Molecular Weight of Polymer Block (A)] The number average molecular weight of the polymer block (A) is preferably 300 to 12,000, more preferably 300 to 11,000, even more preferably 350 to 10,000, still more preferably 400 to 9,500, and still more preferably 500 to 9,000, and may be 600 to 8,500 or 700 to 8,000. Within the above numerical range, the compatibility between the polymer block (A) and the polymer block (B) is excellent, and the balance between strength and flexibility tends to be even better.

[0052] The weight average molecular weight 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, still more preferably 1,300 to 40,000, and even more preferably 1,400 to 30,000, 1,600 to 25,000, or 2,000 to 20,000. Within the above numerical ranges, the compatibility between polymer block (A) and polymer block (B) tends to be excellent, and the balance between strength and flexibility tends to be even better.

[0053] The molecular weight distribution (weight average molecular weight / number average molecular weight) of the polymer block (A) is preferably 1.5 to 10.0, more preferably 1.7 to 8.0, even more preferably 1.8 to 6.0, still more preferably 2.0 to 5.0, and even more preferably 2.0 to 4.0. Within the above numerical range, the compatibility between the polymer block (A) and the polymer block (B) tends to be excellent, and the balance between strength and flexibility tends to be even better.

[0054] In this embodiment, the number average molecular weight and weight average molecular weight of the polymer block (A) and the polyamide block copolymer can be measured by gel permeation chromatography. More specifically, the number average molecular weight of the polymer block (A) and the polyamide block copolymer is a value measured by the method described in the Examples section. The weight average molecular weight of the polymer block (A) and the polyamide block copolymer can be measured by a method similar to the method described in the Examples section.

[0055] <Polymer Block (B)> The polymer block (B) has a glass transition temperature of 20°C or lower. The glass transition temperature of the polymer block (B) is usually the glass transition temperature of the polymer constituting the polymer block (B). If the glass transition temperature of the polymer block (B) exceeds 20°C, it becomes difficult for the polyamide block copolymer to have excellent flexibility. The glass transition temperature of the polymer block (B) is preferably 0°C or lower, more preferably -20°C or lower, from the viewpoint of easily imparting excellent flexibility to the polyamide block copolymer at room temperature. The lower the glass transition temperature of the polymer block (B), the better, but from the viewpoint of heat resistance, it may be -120°C or higher. That is, the glass transition temperature of the polymer block (B) is preferably -120 to 20°C.

[0056] Specifically, the glass transition temperature of the polymer block (B) can be measured by the method described in the Examples section below.

[0057] [Polymer Unit] Examples of the polymer-derived structural units constituting the polymer block (B) include polyether, polyester, polycarbonate, polysiloxane, etc., and preferably an oxygen-atom-containing polymer (hereinafter simply referred to as "oxygen-atom-containing polymer") having an oxygen atom in the polymer-derived structural unit. As the oxygen-atom-containing polymer, polyether is preferred from the viewpoint of exhibiting flexibility. Details of polyether, polyester, polycarbonate, and polysiloxane will be described later. The oxygen-atom-containing polymer preferably contains an oxygen atom in the main chain. The polymer block (B) more effectively contributes to exhibiting flexibility by containing an oxygen atom, preferably an ether bond, in the main chain.

[0058] From the viewpoint of imparting excellent flexibility to the polyamide block copolymer, the content of structural units derived from an oxygen atom-containing polymer in polymer block (B) is preferably 50 mol% or more, more preferably 70 mol% or more, even more preferably 90 mol% or more, and may even be 100 mol%. Furthermore, the content of structural units derived from an oxygen atom-containing polymer in polymer block (B) may be 100 mol% or less. That is, the content of structural units derived from an oxygen atom-containing polymer in polymer block (B) is preferably 50 to 100 mol%.

[0059] In the polymer block (B), the constituent units other than the constituent units derived from the oxygen atom-containing polymer are not particularly limited, and specific examples include polybutadiene and polyisoprene, and the content ratio thereof is not limited as long as it does not excessively impair the effects of the present invention.

[0060] The polymer constituting polymer block (B) preferably has an amino group or a carboxyl group as a terminal group, from the viewpoint of reactivity with the polymer constituting polymer block (A) and with the polymerizable monomer constituting linking group (C). Polymer block (B) preferably contains 50 mol% or more, more preferably 70 mol% or more, even more preferably 90 mol% or more, and may even contain 100 mol% of structural units derived from a polymer having an amino group or a carboxyl group as a terminal group. Furthermore, the content of structural units derived from a polymer having an amino group or a carboxyl group as a terminal group in polymer block (B) may be 100 mol% or less. That is, the content of structural units derived from a polymer having an amino group or a carboxyl group as a terminal group in polymer block (B) is preferably 50 to 100 mol%. The content of structural units in polymer block (B) other than the structural units derived from a polymer having an amino group or a carboxyl group as a terminal group is not limited as long as it does not excessively impair the effects of the present invention.

[0061] <Polyether> In this embodiment, "polyether" refers to polyether polyol, and includes amine derivatives and carboxyl derivatives of polyether polyol. Examples of amine derivatives and carboxyl derivatives of polyether polyol include polyether diamines and polyether dicarboxylic acids. Among them, polyether diamines are preferred from the viewpoint of imparting superior flexibility to polyamide block copolymers having polymer block (A) as hard segments and of being expected to exhibit superior chemical resistance to the polyamide block copolymers. One or more polyethers can be used.

[0062] When the oxygen atom-containing polymer is a polyether, the polymer block (B) contains structural units derived from a polyether polyol, an amine derivative thereof, or a carboxyl derivative thereof. In this case, the polymer block (B) preferably contains 50 mol % or more of structural units derived from a polyether polyol, an amine derivative thereof, or a carboxyl derivative thereof.

[0063] Examples of polyether polyols include polyethylene glycol (PEG), polypropylene glycol (PPG), polytrimethylene ether glycol (PO3G), poly(oxybutylene) glycol, polytetramethylene ether glycol (PTMG), poly(3-alkyltetrahydrofuran), particularly poly(3-methyltetrahydrofuran) (poly(3MeTHF)), polypentamethylene ether glycol, polyhexamethylene ether glycol, polyoctamethylene ether glycol, and copolymers thereof. These may be used alone or in combination.

[0064] Examples of polyether diamines include polyethylene glycol (PEG), polypropylene glycol (PPG), polytrimethylene ether glycol (PO3G), poly(oxybutylene) glycol, polytetramethylene ether glycol (PTMG), poly(3-alkyltetrahydrofuran), particularly poly(3-methyltetrahydrofuran) (poly(3MeTHF)), polypentamethylene ether glycol, polyhexamethylene ether glycol, polyoctamethylene ether glycol, and the like, as well as polyether diamines having amino groups at two ends of their copolymers. These may be used alone or in combination. Such polyether diamines can be obtained, for example, by cyanoacetylation of polyether diol.

[0065] Examples of polyether dicarboxylic acids include polyethylene glycol (PEG), polypropylene glycol (PPG), polytrimethylene ether glycol (PO3G), poly(oxybutylene) glycol, polytetramethylene ether glycol (PTMG), poly(3-alkyltetrahydrofuran), particularly poly(3-methyltetrahydrofuran) (poly(3MeTHF)), polypentamethylene ether glycol, polyhexamethylene ether glycol, polyoctamethylene ether glycol, and polyether dicarboxylic acids having carboxyl groups at two ends of their copolymers. These may be used alone or in combination of two or more.

[0066] <Polyester> In this embodiment, "polyester" means polyester polyol, and also includes derivatives of polyester polyol such as amine derivatives and carboxyl derivatives. One or more types of polyester can be used.

[0067] Examples of polyesters include poly(caprolactone), poly(methylvalerolactone), poly(butylene adipate), poly(ethylene adipate), poly(methylpentanediol adipate), poly(butylene-1,4-hexanediol-1,6-adipate), etc. These can be used alone or in combination of two or more.

[0068] The polyester can be, for example, one produced by polycondensation of a dicarboxylic acid and a polyhydric alcohol. Examples of dicarboxylic acids include aliphatic dicarboxylic acids such as 1,4-cyclohexyldicarboxylic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, tetradecanedicarboxylic acid, and 1,18-octadecanedicarboxylic acid; and dimer fatty acids consisting of one or two types selected from unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid, palmitoleic acid, and elaidic acid. These can be used alone or in combination of two or more types.

[0069] 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, 1,4-cyclohexanedimethanol, etc. These can be used alone or in combination of two or more.

[0070] Examples of the amine derivative in polyester include those in which an amino group is introduced at the end of a polyester polyol, etc. These may be used alone or in combination of two or more.

[0071] Furthermore, examples of the carboxyl derivatives in polyester include those in which a carboxyl group has been introduced at the end of a polyester polyol, etc. The carboxyl derivatives may have at least one carboxyl group at the end, and may, for example, have carboxyl groups at all ends, or may have both carboxyl groups and hydroxyl groups at the ends. These may be used alone or in combination of two or more.

[0072] <Polycarbonate> In this embodiment, "polycarbonate" means polycarbonate polyol, and also includes derivatives of polycarbonate polyol such as amine derivatives and carboxyl derivatives. One or more types of polycarbonate can be used.

[0073] When the oxygen atom-containing polymer is a polycarbonate polyol, its amine derivative, or its carboxyl derivative, the polymer block (B) contains structural units derived from the polycarbonate polyol, its amine derivative, or its carboxyl derivative. In this case, the polymer block (B) preferably contains 50 mol % or more of structural units derived from the polycarbonate polyol, its amine derivative, or its carboxyl derivative.

[0074] Examples of polycarbonates include poly(hexanediol-1,6-carbonate), polytetrahydrofuran carbonate, etc. These may be used alone or in combination of two or more.

[0075] The polycarbonate polyol may be, for example, one produced by an esterification reaction between a carbonate ester and a polyhydric alcohol, or one produced by an interfacial polycondensation method in which a polyhydric alcohol is reacted with phosgene. One or more types of polycarbonate polyols may be used.

[0076] Examples of carbonate esters include methyl carbonate, ethyl carbonate, phenyl carbonate, etc. These may be used alone or in combination of two or more.

[0077] 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, 1,4-cyclohexanedimethanol, etc. These can be used alone or in combination of two or more.

[0078] Examples of the amine derivatives in polycarbonate include those in which an amino group has been introduced at the end of a polycarbonate polyol, etc. One or more of these can be used. Examples of the carboxyl derivatives in polycarbonate include those in which a carboxyl group has been introduced at the end of a polycarbonate polyol, etc. The carboxyl derivatives may have at least one carboxyl group at the end, and may, for example, have carboxyl groups at all ends, or may have both carboxyl groups and hydroxyl groups at the end. One or more of these can be used.

[0079] <Polysiloxane> In this embodiment, "polysiloxane" means polysiloxane polyol, and also includes derivatives of polysiloxane polyol such as amine derivatives and carboxyl derivatives. One or more types of polysiloxane can be used.

[0080] When the oxygen atom-containing polymer is a polysiloxane polyol, its amine derivative, or its carboxyl derivative, polymer block (B) contains structural units derived from the polysiloxane polyol, its amine derivative, or its carboxyl derivative. In this case, polymer block (B) preferably contains 50 mol % or more of structural units derived from the polysiloxane polyol, its amine derivative, or its carboxyl derivative.

[0081] Examples of polysiloxanes include compounds having a hydroxyl group at the end of a polyorganosiloxane having a repeating unit represented by the following formula (X): Specific examples include polydimethylsiloxane diol, polydiphenylsiloxane diol, polytrifluoropropylmethylsiloxane diol, polyphenylmethylsiloxane diol, polydiethylsiloxane diol, polydivinylsiloxane diol, polyvinylmethylsiloxane diol, and poly(5-hexenyl)methylsiloxane diol.

[0082]

[0083] R and R' in formula (X) are organic groups and may be the same or different. The organic group is not limited as long as it does not impair the effects of the present invention, and examples thereof include alkyl groups having 1 to 8 carbon atoms, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and octyl; alkenyl groups having 1 to 5 carbon atoms, such as vinyl, allyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-methylvinyl, and 1-methylallyl; alicyclic alkyl groups, such as cyclohexyl; and aryl groups, such as phenyl, tolyl, xylyl, benzyl, and 2-phenylethyl. Note that hydrogen atoms in the alkyl groups having 1 to 8 carbon atoms may be substituted with fluorine atoms.

[0084] Examples of the amine derivatives in polysiloxane include those in which an amino group has been introduced at the end of a polysiloxane polyol, etc. One or more of these can be used. Furthermore, examples of the carboxyl derivatives in polysiloxane include those in which a carboxyl group has been introduced at the end of a polysiloxane polyol, etc. One or more of these can be used.

[0085] [Molecular Weight] The number average molecular weight of polymer block (B) is preferably 100 or more, more preferably 150 or more, even more preferably 200 or more, still more preferably 300 or more, and even more preferably 400 or more. From the viewpoint of obtaining a polyamide block copolymer having excellent flexibility, particularly tensile properties, it may be 500 or more, 700 or more, or 800 or more. Furthermore, the number average molecular weight of polymer block (B) is not limited as long as the polymerization reaction between the polymer constituting polymer block (B) and the polymer constituting polymer block (A) via the polymerizable monomer constituting linking group (C) proceeds smoothly, but may be, for example, 7,000 or less, 6,000 or less, 5,000 or less, 3,000 or less, or 2,000 or less. That is, the number average molecular weight of polymer block (B) is preferably 100 to 7,000, more preferably 200 to 5,000, even more preferably 500 to 3,000, and even more preferably 700 to 2,000. Within the above numerical range, the polymerization reaction proceeds smoothly, and the resulting polyamide block copolymer has excellent flexibility, tending to have even better tensile properties. More specifically, the number-average molecular weight of the polymer block (B) is a value measured by the method described in the Examples section.

[0086] <Linking Group (C)> The polyamide block copolymer of this embodiment preferably contains a linking group (C) from the viewpoint of improving moldability. In this embodiment, the linking group (C) generally refers to a group that indirectly bonds the polymer block (A) and the polymer block (B). The linking group (C) may consist of one type of linking group or may consist of multiple linking groups.

[0087] The linking group (C) and polymer block (A) are directly bonded, preferably via an amide bond or an ester bond from the viewpoint of smoothly proceeding the polymerization reaction, and more preferably via an amide bond from the viewpoint of hydrolysis resistance and chemical resistance. Similarly, the linking group (C) and polymer block (B) are directly bonded, preferably via an amide bond or an ester bond from the viewpoint of smoothly proceeding the polymerization reaction, and more preferably via an amide bond from the viewpoint of hydrolysis resistance and chemical resistance.

[0088] When the linking group (C) is composed of a plurality of linking groups, the plurality of linking groups join together to link the polymer block (A) and the polymer block (B).

[0089] The polyamide block copolymer of this embodiment may not contain a linking group (C). In this case, the polymer block (A) and the polymer block (B) are directly bonded to each other through a bond derived from a reactive functional group possessed by the polymer for polymer block (A) and a reactive functional group possessed by the polymer for polymer block (B). From the viewpoint of smoothly proceeding the polymerization reaction, the bond is preferably an amide bond or an ester bond, and from the viewpoint of hydrolysis resistance and chemical resistance, the bond is more preferably an amide bond.

[0090] The linking group (C) may be a divalent group, a trivalent group, or a tetravalent or higher valent group.

[0091] The linking group (C) typically contains a structural unit derived from a polymerizable monomer capable of forming the linking group (C). Examples of such polymerizable monomers include a polymerizable monomer (c1) having three or more reactive functional groups and a bifunctional polymerizable monomer (c2). That is, the linking group (C) may contain a structural unit (C-1) derived from the polymerizable monomer (c1), a structural unit (C-2) derived from the polymerizable monomer (c2), or both the structural unit (C-1) and the structural unit (C-2). When a polyamide block copolymer contains the structural unit (C-1), the polyamide block copolymer typically falls under the category of a branched polymer as defined by IUPAC. Furthermore, when a polyamide block copolymer does not contain the structural unit (C-1), the polyamide block copolymer can be considered a linear polymer.

[0092] (Structural Unit (C-2) and Polymerizable Monomer (c2)) As described above, the polymerizable monomer (c2) is a bifunctional polymerizable monomer. However, the bifunctional polymerizable monomer excludes the polymer constituting the polymer block (A) and the polymer constituting the polymer block (B). Typically, the polymerizable monomer (c2) reacts with the end of the polymer constituting the polymer block (A) or the end of the polymer constituting the polymer block (B). That is, the polymerizable monomer (c2) functions as a terminal functionalizing agent. In one embodiment, the polymerizable monomer (c2) functionalizes the end of the polymer constituting the polymer block (A). For example, if the polymer constituting the polymer block (A) is a polyamide having an amino group at one end (amino terminal) and a carboxyl group at the other end, it is possible to convert the amino terminal of the polyamide to a carboxyl group via the structural unit (C-2) by using a monomer having two carboxyl groups as the terminal functionalizing agent as the polymerizable monomer (c2). In another embodiment, the polymerizable monomer (c2) functionalizes the terminal of the polymer constituting the polymer block (B).

[0093] [Terminal Functionalizing Agent] In one embodiment, a terminal functionalizing agent can be used to adjust the terminal of the polymer block (A), preferably the terminal of the semi-aromatic polyamide, to a desired functional group. In this manner, a polymer block (2A) can be obtained in which the polymer block (A) and the structural unit (C-2) are bonded. For example, by reacting the aforementioned semi-aromatic polyamide prepolymer with a terminal functionalizing agent, the terminal of the semi-aromatic polyamide can be converted to the other terminal of the terminal functionalizing agent. By adjusting the terminal of the polymer block (A) to a desired functional group, the polymer block (A) and the polymer block (B) can be more effectively linked via the linking group (C).

[0094] When the semi-aromatic polyamide has the desired functional groups, a terminal functionalizing agent does not need to be used. That is, in this case, the polymer constituting polymer block (A) and the polymer constituting polymer block (B) can be reacted directly or indirectly (for example, via a polymerizable monomer having three or more reactive functional groups constituting linking group (C)) without using a terminal functionalizing agent, thereby enabling good linking of polymer block (A) and polymer block (B).

[0095] The terminal functionalizing agent is not limited as long as it does not impair the effects of the present invention, and examples thereof include those that can introduce functional groups such as hydroxyl groups, carboxyl groups, amino groups, epoxy groups, mercapto groups, sulfonyl groups, halogen atoms, vinyl groups, and vinylidene groups into the terminals of the polymers that constitute the polymer block (A), for example, the terminals of semi-aromatic polyamides.

[0096] In this embodiment, the terminal functionalizing agent is preferably a compound selected from the group consisting of dicarboxylic acids and diamines. In this case, the polymer block (2A) contains structural units derived from the semi-aromatic polyamide and structural units derived from the compound selected from the group consisting of dicarboxylic acids and diamines.

[0097] Dicarboxylic acids that can be used as the terminal functionalizing agent include aliphatic dicarboxylic acids and aromatic dicarboxylic acids. From the viewpoint of increasing the strength of the polyamide block copolymer, it is preferable to use aromatic dicarboxylic acids as the terminal functionalizing agent. From the viewpoint of increasing the flexibility of the polyamide block copolymer, it is preferable to use aliphatic dicarboxylic acids as the terminal functionalizing agent.

[0098] 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, and dodecanedicarboxylic 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.

[0099] Examples of aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, diphenic acid, 4,4'-biphenyldicarboxylic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 2,3-furandicarboxylic acid, 2,4-furandicarboxylic acid, 2,5-furandicarboxylic acid, and 3,4-furandicarboxylic acid.

[0100] Diamines that can be used as the terminal functionalizing agent include aliphatic diamines and aromatic diamines. From the viewpoint of increasing the strength of the polyamide block copolymer, it is preferable to use an aromatic diamine as the terminal functionalizing agent. From the viewpoint of increasing the flexibility of the polyamide block copolymer, it is preferable to use an aliphatic diamine as the terminal functionalizing agent.

[0101] Examples of aliphatic diamines include linear aliphatic diamines such as ethylenediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 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;1,2-propanediamine, 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 hexanediamine, 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, 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- branched aliphatic diamines such as octanediamine, 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;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 are listed. Examples of aromatic diamines include p-phenylenediamine, m-phenylenediamine, p-xylylenediamine, m-xylylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylether, and 4,4'-methylenedi-2,6-diethylaniline. The above terminal functionalizing agents may be used alone or in combination of two or more.

[0102] (Structural Unit (C-1) and Polymerizable Monomer (c1)) As described above, the polymerizable monomer (c1) is a polymerizable monomer having three or more reactive functional groups.

[0103] To take a first example of a case where the polymerizable monomer (c1) is trifunctional, one polymer block (A) and two polymer blocks (B) can be linked via the structural unit (C-1) derived from the polymerizable monomer (c1). This results in a polyamide block copolymer (hereinafter also referred to as a "hard branched copolymer") in which two polymer blocks (B) as soft segments are linked to the polymer block (A) as a hard segment via a branch point contained in the structural unit (C-1). To achieve the above-mentioned linkage, a polymer for the polymer block (A) may first be bonded to the polymerizable monomer (c1), thereby forming a polymer block (3A) containing the polymer block (A) and the structural unit (C-1), and then the polymer block (B) may be bonded to the remaining two ends of the polymerizable monomer (c1). In the hard branched copolymer, the aforementioned structural unit (C-2) may be present between the polymer block (A) and the structural unit (C-1), or the aforementioned structural unit (C-2) may be present between the polymer block (B) and the structural unit (C-1).

[0104] In a second example where the polymerizable monomer (c1) is trifunctional, two polymer blocks (A) and one polymer block (B) can be linked via the structural unit (C-2) derived from the polymerizable monomer (c1). This results in a polyamide block copolymer (hereinafter also referred to as a "soft branched copolymer") in which two polymer blocks (A), which are hard segments, are linked to the polymer block (B), which is a soft segment, via a branch point contained in the structural unit (C-2). To achieve the above-mentioned linkage, a polymer for polymer block (B) may first be bonded to the polymerizable monomer (c1), thereby forming a polymer block (3B) containing the polymer block (B) and the structural unit (C-1), and then the polymer block (A) may be bonded to the remaining two ends of the polymerizable monomer (c1). In the soft branched copolymer, the aforementioned structural unit (C-2) may be present between the polymer block (A) and the structural unit (C-1), or the aforementioned structural unit (C-2) may be present between the polymer block (B) and the structural unit (C-1).

[0105] As in the first and second examples described above, the polyamide block copolymer contains the structural unit (C-1), i.e., a branching point, thereby realizing a branched polymer. From the viewpoint of increasing the value of the strain hardening parameter H and further improving moldability, it is preferable that the polyamide block copolymer is a branched polymer.

[0106] Methods for forming branch points in polyamide block copolymers include adding a polymerizable monomer (c1), such as a polyfunctional species having three or more functional groups capable of reacting with one or more of a carboxyl group, an amino group, and a hydroxyl group, during polymerization, adding a polymerizable monomer (c1), such as the above-mentioned polyfunctional species, to the copolymer, or irradiating with electron beams or gamma rays. These methods may be used alone or in combination of two or more. From the viewpoint of adjusting the number of branch points and the average molecular weight between the branch points and obtaining the desired resin properties, it is preferable to use a method in which a polymerizable monomer (c1) is added during polymerization.

[0107] Examples of the polymerizable monomer (c1) include polyamines, polycarboxylic acids, polyols, polyepoxides, and polyisocyanates each having three or more reactive functional groups.

[0108] Examples of polyamines include diethylenetriamine, triethylenetetramine, melamine, trimethylolpropane poly(oxypropylene)triamine, and glyceryl poly(oxypropylene)triamine.

[0109] Examples of polycarboxylic acids include trimellitic acid, trimesic acid, and pyromellitic acid.

[0110] Examples of polyols include glycerin and triethanolamine.

[0111] Examples of polyepoxides include trimethylolpropane triglycidyl ether.

[0112] Examples of polyisocyanates include lysine triisocyanate.

[0113] The polymerizable monomer (c1) may be used alone or in combination of two or more. From the viewpoint of improving physical properties such as heat resistance, the polymerizable monomer (c1) is preferably a polyamine having three or more amino groups, more preferably a polyether having three or more amino groups at its terminal, and even more preferably a polyamine having a polyether structure as a repeating unit in its main chain. From the viewpoint of improving physical properties such as flexibility, the polymerizable monomer (c1) is preferably a polycarboxylic acid having three or more carboxyl groups.

[0114] <Method for Producing Polyamide Block Copolymer> The method for producing the polyamide block copolymer of this embodiment is not particularly limited, and it is preferable to mix and copolymerize a polymer constituting the polymer block (A), a polymer constituting the polymer block (B), and, if necessary, a polymerizable monomer (c1) and, if necessary, a polymerizable monomer (c2).

[0115] In the above production method, an end-capping agent and / or an end-functionalizing agent (polymerizable monomer (c2)) may be used. The end-capping agent and / or the end-functionalizing agent may be added before polymerization, at the stage of producing the polymer constituting polymer block (A) or the polymer constituting polymer block (B), at the stage of copolymerizing the polymer constituting polymer block (A) and the polymer constituting polymer block (B), or at the stage after polymerization.

[0116] In the above-mentioned production method, a polymerizable monomer (c1) may be added at any stage: before polymerization, at the stage of polymerizing the polymer constituting polymer block (A) or the polymer constituting polymer block (B), at the stage of copolymerizing the polymer constituting polymer block (A) and the polymer constituting polymer block (B), or after polymerization.

[0117] As the polymerization method, methods such as melt polymerization, solution polymerization, solid-state polymerization, melt extrusion polymerization, etc. may be usually employed. Melt polymerization or solution polymerization may be combined with melt extrusion polymerization and / or solid-state polymerization.

[0118] The reaction temperature in the melt polymerization method and melt extrusion polymerization is preferably 400° C. or lower, more preferably 350° C. or lower, and even more preferably 320° C. or lower, from the viewpoint of preventing deterioration due to heat.

[0119] <Mass Ratio (A) / (B)> In the polyamide block copolymer of this embodiment, the mass ratio (A) / (B) of polymer block (A) to polymer block (B) is preferably 1 / 99 to 99 / 1, more preferably 5 / 95 to 95 / 5, even more preferably 10 / 90 to 95 / 5, still more preferably 20 / 80 to 95 / 5, still more preferably 40 / 60 to 90 / 10, still more preferably 50 / 50 to 85 / 15, and even more preferably 60 / 40 to 85 / 15. When the mass ratio (A) / (B) is within the above range, the polyamide block copolymer is likely to exhibit both excellent heat resistance and flexibility.

[0120] <Polymer Block Content> From the viewpoint of obtaining a polyamide block copolymer having excellent strength, the content of the polymer block (A) in 100% by mass of the total amount of the polyamide block copolymer is preferably 40% by mass or more, more preferably 45% by mass or more, even more preferably 46% by mass or more, and still more preferably 49% by mass or more or 50% by mass or more. From the viewpoint of obtaining a polyamide block copolymer having excellent elongation or flexibility, the content of the polymer block (A) in 100% by mass of the total amount of the polyamide block copolymer is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 88% by mass or less or 85% by mass or less.

[0121] The content of polymer block (B) in 100% by mass of the total amount of the polyamide block copolymer is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 12% by mass or more or 15% by mass or more, and in some cases may be 20% by mass or more or 25% by mass or more, from the viewpoint of obtaining a polyamide block copolymer having excellent elongation or flexibility. The content of polymer block (B) in 100% by mass of the total amount of the polyamide block copolymer is preferably 60% by mass or less, more preferably 55% by mass or less, even more preferably 54% by mass or less or 51% by mass or less, from the viewpoint of obtaining a polyamide block copolymer having excellent strength.

[0122] The total amount of polymer block (A) and polymer block (B) in 100% by mass of the total amount of the polyamide block copolymer is, for example, 50% by mass or more, 60% by mass or more, 70% by mass or more, or 80% by mass or more. From the viewpoint of obtaining a polyamide block copolymer having an excellent balance between strength and flexibility, the total amount is preferably 85% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more.

[0123] From the viewpoint of obtaining a polyamide block copolymer having excellent strength, the content of polymer block (A) in 100 mol% of the total amount of the polyamide block copolymer is preferably 35 mol% or more, more preferably 40 mol% or more, even more preferably 42 mol% or more, and even more preferably 44 mol% or more or 45 mol% or more. From the viewpoint of obtaining a polyamide block copolymer having excellent elongation or flexibility, the content of polymer block (A) in 100 mol% of the total amount of the polyamide block copolymer is preferably 65 mol% or less, more preferably 60 mol% or less, even more preferably 59 mol% or less or 58 mol% or less.

[0124] From the viewpoint of obtaining a polyamide block copolymer having excellent strength, the content of polymer block (2A) in 100 mol% of the total amount of the polyamide block copolymer is preferably 35 mol% or more, more preferably 40 mol% or more, even more preferably 42 mol% or more, and even more preferably 44 mol% or more or 45 mol% or more. From the viewpoint of obtaining a polyamide block copolymer having excellent elongation or flexibility, the content of polymer block (2A) in 100 mol% of the total amount of the polyamide block copolymer is preferably 65 mol% or less, more preferably 60 mol% or less, even more preferably 59 mol% or less or 58 mol% or less.

[0125] From the viewpoint of obtaining a polyamide block copolymer having excellent moldability, the content of polymer block (3A) in 100 mol% of the total amount of the polyamide block copolymer is preferably 0 mol% or more, more preferably 1 mol% or more, even more preferably 2 mol% or more, and even more preferably 3 mol% or more. From the viewpoint of obtaining a polyamide block copolymer having excellent thermoplasticity, the content of polymer block (3A) in 100 mol% of the total amount of the polyamide block copolymer is preferably 20 mol% or less, more preferably 15 mol% or less, even more preferably 13 mol% or less or 11 mol% or less.

[0126] From the viewpoint of obtaining a polyamide block copolymer having excellent moldability, the content of the structural units derived from the polymerizable monomer (c1) in 100 mol% of the total amount of the polyamide block copolymer is preferably 0 mol% or more, more preferably 1 mol% or more, even more preferably 2 mol% or more, and even more preferably 3 mol% or more. From the viewpoint of obtaining a polyamide block copolymer having excellent thermoplasticity, the content of the structural units derived from the polymerizable monomer (c1) in 100 mol% of the total amount of the polyamide block copolymer is preferably 20 mol% or less, more preferably 15 mol% or less, and even more preferably 13 mol% or less or 11 mol% or less.

[0127] From the viewpoint of obtaining a polyamide block copolymer having excellent elongation or flexibility, the content of polymer block (B) in 100 mol% of the total amount of the polyamide block copolymer is preferably 30 mol% or more, more preferably 35 mol% or more, even more preferably 36 mol% or more, and even more preferably 37 mol% or more or 38 mol% or more. From the viewpoint of obtaining a polyamide block copolymer having excellent elongation or flexibility, the content of polymer block (B) in 100 mol% of the total amount of the polyamide block copolymer is preferably 65 mol% or less, more preferably 60 mol% or less, and even more preferably 57 mol% or less or 55 mol% or less.

[0128] From the viewpoint of obtaining a polyamide block copolymer having excellent moldability, the molar ratio (branching ratio) of the structural unit or polymer block (3A) derived from the polymerizable monomer (c1) having three or more reactive functional groups in 100 mol% of the total amount of the polyamide block copolymer is preferably 0 mol% or more, more preferably 1 mol% or more, even more preferably 2 mol% or more, and even more preferably 3 mol% or more. From the viewpoint of obtaining a polyamide block copolymer having excellent thermoplasticity, the molar ratio of the structural unit or polymer block (3A) derived from the polymerizable monomer (c1) having three or more reactive functional groups in 100 mol% of the total amount of the polyamide block copolymer is preferably 20 mol% or less, more preferably 15 mol% or less, and even more preferably 13 mol% or less or 11 mol% or less.

[0129] The total amount of polymer block (A) and polymer block (B) in 100 mol% of the total amount of the polyamide block copolymer is, for example, 50 mol% or more, 60 mol% or more, 70 mol% or more, or 80 mol% or more. From the viewpoint of obtaining a polyamide block copolymer having an excellent balance between strength and flexibility, the total amount is preferably 85 mol% or more, more preferably 90 mol% or more, and even more preferably 95 mol% or more.

[0130] The mass ratio and molar ratio of polymer blocks or polymerizable monomers in a polyamide block copolymer can be determined by the following method: １One example of such a method is to measure the integral ratio of signals derived from each polymer block or polymerizable monomer using H-NMR, and determine the content of each structural unit from the ratio.

[0131] <Molecular Weight of Polyamide Block Copolymer> The number average molecular weight of the polyamide block copolymer is, for example, 150,000 or less, preferably 20,000 to 150,000, more preferably 20,000 to 130,000, even more preferably 30,000 to 120,000, still more preferably 40,000 to 110,000, and even more preferably 40,000 to 100,000. The higher the molecular weight, the better the heat resistance, but the lower the moldability tends to be. Within the above numerical range, the heat resistance of the polyamide block copolymer can be further improved and good moldability can be expected.

[0132] The weight-average molecular weight of the polyamide block copolymer is, for example, 500,000 or less, preferably 30,000 to 500,000, more preferably 40,000 to 400,000, even more preferably 42,000 to 350,000 or 50,000 to 350,000, still more preferably 63,000 to 330,000, and even more preferably 75,000 to 330,000, for example, 100,000 to 330,000 or 100,000 to 300,000. Within the above numerical range, the polyamide block copolymer can be expected to exhibit stronger material properties and have good moldability.

[0133] The molecular weight distribution (weight average molecular weight / number average molecular weight) of the polyamide block copolymer is preferably 2.0 to 14.5, more preferably 2.0 to 12.0, and even more preferably 2.0 to 10.0, and may be, for example, 2.5 to 8.0 or 2.5 to 6.0. When the molecular weight distribution is within the above numerical range, the heat resistance of the polyamide block copolymer can be further improved and good moldability can be expected.

[0134] <Melting Point (Heat Resistance) of Polyamide Block Copolymer> The melting point of the polyamide block copolymer is preferably 120°C or higher, more preferably 180°C or higher, even more preferably 230°C or higher, still more preferably 235°C or higher, and even more preferably 237°C or higher. A polyamide block copolymer with a melting point of 120°C or higher, more preferably 180°C or higher, and even more preferably 230°C or higher, exhibits excellent heat resistance. Furthermore, a polyamide block copolymer with a melting point of 120°C or higher tends to exhibit good mechanical properties. Furthermore, a polyamide block copolymer with a melting point of 230°C or higher facilitates further improvement of heat resistance. While there is no particular upper limit for the melting point of the polyamide block copolymer, from the viewpoint of moldability, etc., it is preferably 320°C or lower, more preferably 280°C or lower, and even more preferably 260°C or lower. That is, the melting point of the polyamide block copolymer is preferably 120 to 320°C, more preferably 180 to 280°C, and even more preferably 230 to 260°C.

[0135] The melting point of the polyamide block copolymer can be determined as the peak temperature of the melting peak that appears when the temperature is increased at a rate of 10°C / min using a differential scanning calorimetry (DSC) analyzer. More specifically, it can be determined by the method described in the Examples below.

[0136] <Average molecular weight between branch points in polyamide block copolymer> The average molecular weight between branch points in a polyamide block copolymer can be theoretically calculated from the charging ratio of each raw material or the ratio of the above-mentioned constituent units in mass % and mol %. From the viewpoints of melt viscosity control, ease of polymerization, and moldability, the average molecular weight of the chain between branch points is preferably 1,000 or more, more preferably 3,000 or more, and even more preferably 6,000 or more. The average molecular weight of the chain between branch points in hard branched copolymers and soft branched copolymers is usually lower than the number average molecular weight of a copolymer without corresponding branch chains ("linear copolymer"). From the viewpoint of reliably achieving the intended effects of the present invention, the average molecular weight between branch points in a polyamide block copolymer is preferably 75,000 or less, more preferably 73,000 or less, even more preferably 71,000 or less, even more preferably 60,000 or less, and even more preferably 40,000 or less.

[0137] <Complex Shear Viscosity η0> In this embodiment, the "complex shear viscosity η0" refers to the complex shear viscosity of a first test piece of a polyamide block copolymer measured in accordance with JIS K7244-10:2005 using a parallel plate oscillatory rheometer at a temperature 30°C higher than the melting point and at an angular frequency of 0.0628 to 628 rad·s. －１ The measurement is performed while changing the logarithmic sweep (frequency dependent measurement) to an angular frequency of 6.28 rad·s －１ is the value of the complex shear viscosity at

[0138] From the viewpoint of obtaining a polyamide block copolymer having excellent moldability and fluidity in a melt, the complex shear viscosity is 500 to 10,000 Pa·s, preferably 600 to 8,000 Pa·s, more preferably 700 to 7,000 Pa·s, and even more preferably 800 to 6,000 Pa·s.

[0139] <Strain hardening parameter H> The strain hardening parameter H represents the ratio of the first viscosity η1 to the second viscosity η2. The first viscosity η1 and the second viscosity η2 will be described later. From the viewpoint of improving moldability in molding techniques involving elongation deformation such as foam molding and blow molding, the strain hardening parameter H is 3.0 or more, preferably 3.5 or more, more preferably 5.0 or more, even more preferably 8.0 or more, and even more preferably 10 or more. The upper limit of the strain hardening parameter H is not limited as long as the effects of the present invention are not impaired, but is, for example, 100 or less. From the viewpoint of reliably achieving the intended effects of the present invention, it is preferably 50 or less, more preferably 45 or less, even more preferably 42 or less, and even more preferably 38 or less.

[0140] The mechanism by which the effects of the present invention are exhibited is, for example, that in foam molding, by adjusting the complex shear viscosity and strain hardening parameter H of the polyamide block copolymer containing the polymer block (A) derived from a highly heat-resistant semi-aromatic polyamide within an appropriate range, the balance between foamability and cell breaking ability is controlled and shape retention after foaming is improved. This makes it possible to obtain a foam with high heat resistance and low specific gravity. It is presumed that this mechanism is responsible for the excellent balance between heat resistance and moldability of the polyamide block copolymer according to this embodiment.

[0141] <First Viscosity η1 (Maximum Attained Extensional Viscosity)> In this embodiment, the "first viscosity η1" refers to the maximum extensional viscosity value in extensional viscosity measurement. Specifically, the first viscosity η1 is the maximum attained extensional viscosity (Pa s) when a second test piece of the polyamide block copolymer having a thickness of 0.8 mm, a long side of 20 mm, and a short side of 10 mm is subjected to an extension test along the long side direction at a temperature 10°C higher than the melting point and a strain rate of 1.0 / s. The maximum attained extensional viscosity value is determined as follows depending on the condition of the sample after measurement. [1] If the test piece breaks before the true strain (logarithmic strain) reaches 3.8, the extensional viscosity value at the true strain at break is taken as the maximum attained extensional viscosity. [2] If the test piece does not break before the true strain (logarithmic strain) reaches 3.8, the extensional viscosity value at a true strain of 3.8 is taken as the maximum attained extensional viscosity. The extensional viscosity measurement can be carried out in more detail by the method described in the Examples.

[0142] <Second Viscosity η2 (Linear Viscosity Growth Curve)> In this embodiment, the "second viscosity η2" refers to a value (Pa s) that is three times the viscosity value when the extension time t1 (s) at which the maximum attained extensional viscosity η1 is achieved is substituted for time t in the shear viscosity growth function η(t) when the polyamide block copolymer exhibits linear viscoelasticity. Regarding the extension time t1, it means that the first viscosity η1 and the second viscosity η2 are at the same time (t1) in FIG. 1 .

[0143] The second viscosity η2 was calculated by using the shear storage modulus G′ [Pa], the shear loss modulus G″ [Pa], and the extension time t1 (s) measured at a temperature 10° C. higher than the melting point using a parallel plate vibration rheometer in accordance with JIS K7244-10:2005, in accordance with the following formula (function 3η corresponding to three times the shear viscosity growth function η(t)): ＋ (t)) can be obtained by substituting 3η ＋ (t)=3t[G″(ω)+1.12G′(ω / 2)−0.200G′(ω)] In the above formula, ω is the reciprocal of the extension time t1. The above formula is quoted from Non-Patent Document 1 (J. Soc. Rheol. Jpn 4 (1976) 166).

[0144] <Expansion Ratio (Molding Processability) of Polyamide Block Copolymer> The polyamide block copolymer according to this embodiment has excellent moldability, as exemplified in the examples.

[0145] As a first example, the first foaming condition (processing gas: N ２ When a polyamide block copolymer is foamed under the conditions of (a) a processing temperature of 270°C and (b) a processing pressure of 40 MPa, the foaming ratio is usually 2.0 or more, preferably 3.0 or more, more preferably 3.2 or more, even more preferably 3.4 or more, and still more preferably 3.6 or more. Here, the expansion ratio is defined as the density ρ0 (g / cm) of the foam before foaming. ３ ) Apparent density ρ1 (g / cm ３ The density ρ0 and apparent density ρ1 can be measured by the method described in the Examples section.

[0146] As a second example, the second foaming condition (processing gas: N ２ When the polyamide block copolymer is foamed under the conditions of (a) a foaming temperature of 270°C and (b) a foaming pressure of 30 MPa, the foaming ratio is usually 1.5 or more, preferably 3.0 or more, more preferably 3.1 or more, even more preferably 3.2 or more, and still more preferably 3.3 or more.

[0147] As a third example, the third foaming condition (processing gas: CO ２ When the polyamide block copolymer is foamed under the conditions of (treatment temperature: 270°C, treatment pressure: 30 MPa), the foaming ratio is usually 3.0 or more, preferably more than 3.0, and more preferably 3.1 or more.

[0148] From the viewpoint of increasing versatility in terms of foaming conditions, the polyamide block copolymer according to this embodiment preferably has an expansion ratio of 1.5 or more, and more preferably 3.0 or more, under any of the first, second, and third foaming conditions.

[0149] <Polyamide Block Copolymer Composition> One embodiment of this invention is a polyamide block copolymer composition containing the polyamide block copolymer. The polyamide block copolymer composition is produced by adding components other than the polyamide block copolymer to the polyamide block copolymer. Examples of such components include additives such as antioxidants, antiozonants, weathering stabilizers, UV absorbers, hydrolysis-resistant stabilizers, fillers, nucleating agents, reinforcing agents, carbon black, pigments, inorganic dyes, organic dyes, colorants, color inhibitors, antigelling agents, delustering agents, antistatic agents, plasticizers, lubricants, mold release agents, shrinkage resistance agents, compatibilizers, flame retardants, flame retardant assistants, blowing agents, and blowing assistants. These additives may be used alone or in combination.

[0150] The content of the additives 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 the polyamide block copolymer.

[0151] Examples of the method for adding the additives include a method of adding them during polymerization of the polyamide block copolymer, and a method of dry blending them with the polyamide block copolymer and melt-kneading them.

[0152] [Method for Producing Polyamide Block Copolymer Composition] The method for producing the polyamide block copolymer composition is not particularly limited, and any method that can uniformly mix the polyamide block copolymer and the above-mentioned additives can be preferably used. Mixing is typically performed by melt-kneading using a single-screw extruder, twin-screw extruder, kneader, Banbury mixer, or the like. The melt-kneading conditions are not particularly limited, and examples include melt-kneading for approximately 1 to 120 minutes at a temperature range approximately 0 to 60°C higher than the melting point of the polyamide block copolymer.

[0153]

[0033] <<Molded Article>> In one embodiment of the present invention, a molded article may be formed from the polyamide block copolymer or the polyamide block copolymer composition. The molded article of this embodiment can be used as an electric / electronic part, an automobile part, an industrial part, a fiber, a film, a sheet, a household product, or any other molded article of any shape and for any purpose.

[0154] <Method for producing molded article> The method for producing a molded article is not particularly limited, and examples thereof include various conventional molding methods, such as injection molding, blow molding, press molding, extrusion molding, calendar molding, vacuum molding, pressure molding, bead molding, batch foam molding, etc. Examples of forms of the molded article include pellets, sheets, plates, pipes, tubes, rods, granules, and foams.

[0155] <Foam> One advantageous aspect of the molded article is a foam. Foams will now be described. The foam according to this embodiment refers to a molded article obtained by foaming the polyamide block copolymer according to the above-described embodiment, preferably a branched polymer. The foam according to this embodiment may contain minute regions (crosslinks) in the polymer resulting from at least four chains, but it is preferable that the foam does not contain such crosslinked sites, or that even if it does contain such crosslinked sites, it is in a very small amount. More preferably, the foam according to this embodiment is a foam whose molecular weight can be measured using an eluent and GPC. A foam whose molecular weight can be measured typically does not contain crosslinked products whose molecular weight cannot be measured using an eluent and GPC, and does not contain gels that are insoluble in many types of organic solvents (common eluents).

[0156] The method for producing a foam includes, for example, the steps of (1) extrusion, (2) foaming, (3) expansion process, and (4) molding. In the (1) extrusion process, mixing and kneading are performed as necessary. In the (2) foaming process, a chemical foaming agent, preferably an organic foaming agent, or a supersaturated gas, preferably an inert gas, may be used, or both a foaming agent and a supersaturated gas may be used. Since the resin of the present invention has excellent heat resistance and therefore requires a relatively high temperature for molding, a method using an inert gas is preferred. In the (3) expansion process, free expansion may be performed, for example, in an oven, or limited expansion may be performed, for example, in a mold. (4) Molding may be performed in a batch system or a continuous system. Examples of molding methods include press molding, vacuum molding, embossing, and over-injection. The method for producing a foam is not limited to the above examples. To produce the foam, any of injection molding, blow molding, extrusion molding, calendar molding, pressure molding, bead molding, batch foam molding, cutting, punching, scraping, and coating (e.g., adhesive coating, extrusion coating) may be used instead of or in addition to the above processes.

[0157] Applications of the foam include soccer balls, sports glove pads (goalkeeper, boxing, etc. pads), immersion suits, golf club grips, rebound layers for table tennis rackets, ski poles, sports bat grips, snowboard or windsurfing pads, saddles (e.g., bicycle saddles), cushions (e.g., ski lift seat cushions, pillow cushions, mattress cushions, chair cushions, etc.), ski boot components; anti-slip coated tape; underwear (e.g., bra cups); mouse pads, soft keyboards, buttons; equipment trays (e.g., automotive equipment trays); gaskets; flexographic printing rolls; single-sided adhesive coated tape, double-sided adhesive coated tape; orthopedic insoles or inlays, footwear insoles or inner soles, footwear midsoles, footwear linings, waterproof and breathable insoles or midsoles, footwear shafts or heel inserts, forefoot inserts; transdermal pads, transdermal absorption pads, wound healing plasters; sportswear, and apparel linings.

[0158] <Applications> The polyamide block copolymer and polyamide block copolymer composition of this embodiment can have an excellent balance between heat resistance and moldability, and can therefore be used in a wide range of fields where these properties are required. For example, the polyamide block copolymer and polyamide block copolymer composition of this embodiment can be widely used as various component materials, such as electrical and electronic components, automotive components, industrial material components, industrial parts, daily necessities, household goods, sports parts, leisure parts, and medical parts. In particular, they can be used for hollow molded parts produced by blow molding, hose and tubular parts, films, and sheets produced by extrusion molding, lightweight components and insulating materials produced by injection and / or extrusion foam molding, and as additives for modifying resins. They can also be used for molded products produced by injection molding, blow molding, press molding, extrusion molding, calendar molding, vacuum forming, and pressure forming.

[0159] More specifically, among electronic and electrical parts, it can be used as a material for hinges of mobile phones and game machines, camera grips, printer tractor belts, electrical wire coatings, tubes for home appliances, etc.

[0160] More specifically, among automotive parts, the material can be used as a material for constant velocity joint boot parts, curl 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, tire inner liners, etc.

[0161] More specifically, among industrial material parts and / or industrial components, the material can be used as a material for submersible pumps, seal members, bushings, tubes, spiral tubes, diaphragms, mop joints, noiseless gears, mandrels, films, nonwoven fabrics, monofilaments, ball joint sheets, register rods, fire hoses, conveyor belts, pulleys, wire cables, etc.

[0162] More specifically, among daily commodities and / or household goods, the material can be used as a material for hair dryer brushes, nail polish cases, hot curlers, zipper pulls, bobbin cases, console shutters, corrugated tubes, corrugated hoses, pillow cushioning, mattress cushioning, chair cushioning, etc.

[0163] More specifically, the material can be used for sports parts such as running shoes, spiked shoes, and ski boots.

[0164] More specifically, among medical components, the material can be used as a material for medical catheters, wearable devices, optical products, eye care components, etc.

[0165] The present invention will be specifically explained below with reference to examples and comparative examples, but the present invention is not limited to these.

[0166] <Measurement and Evaluation Methods> Various physical properties were measured or evaluated by the following methods.

[0167] [1. Glass Transition Temperature] The polyamides obtained in the synthesis examples described below and the polyetherdiamine constituting the polymer block (B) were used as samples, and their glass transition temperatures were measured using a differential scanning calorimeter "DSC25" manufactured by TA Instruments. The glass transition temperatures were measured in accordance with ISO 11357-3 (2011, 2nd edition). Specifically, the glass transition temperature was determined as the temperature of the inflection point in a DSC curve measured by increasing the temperature from -90°C to 300°C at a rate of 10°C / min.

[0168] [2. Molecular Weight] (2-1. Number-Average Molecular Weight of Polyamide and Polyamide Block Copolymer) The polyamides obtained in the Synthesis Examples and the polyamide block copolymers obtained in the Examples and Comparative Examples described below were used as samples, and the number-average molecular weight (Mn) was determined by gel permeation chromatography (GPC) in terms of standard polymethyl methacrylate-equivalent molecular weight. An HFIP solution prepared by dissolving 0.85 g of sodium trifluoroacetate in 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 dissolved in 3 mL of the 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 (Tosoh Corporation) columns were 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" manufactured by Showa Denko K.K., "Polymethylmethacrylate" manufactured by Agilent Technologies (polymethyl methacrylate with molecular weights of 1010 and 535) Detector: UV (254 nm) detector, UV (210 nm) detector

[0169] (2-2. Number Average Molecular Weight of Polyether Constituting Polymer Block (B)) The number average molecular weight (Mn) of the polyether constituting the polymer block (B) was determined as follows.

[0170] The polyetherdiamine constituting the polymer block (B) was used as a sample. 0.1 g of the sample was dissolved in 35 mL of phenol, and 3 mL of methanol was added to prepare a sample solution. Titration was carried out using 0.1 N aqueous HCl solution with thymol blue as an indicator to determine the terminal amino group content ([NH ２ ], unit: μmol / g) was measured. From the obtained terminal amino group content, the number average molecular weight (Mn) of the polyether constituting the polymer block (B) was calculated based on the following formula: Number average molecular weight (Mn) = 10 ６ / [NH ２ ]

[0171] [3. Content (mol %) of each structural unit in the block copolymer] From the charged amounts of each raw material of the polyamide block copolymer obtained in the Examples and Comparative Examples, the content (mol %) of α. polymer block (A), the content (mol %) of β. polymer block (2A), the content (mol %) of γ. polymer block (3A), the content (mol %) of δ. the content (mol %) of the structural unit derived from the polymerizable monomer (c1-2) described below, and the content (mol %) of ε. polymer block (B) were determined as percentages relative to the total content of α to ε, taken as 100 mol %. The results are shown in Table 1. Here, the polymer block (2A) was a structural unit derived from a dicarboxylic acid obtained by reacting the polyamide obtained in the Synthesis Examples with a bifunctional polymerizable monomer (specifically, polymerizable monomer (c2)). The polymer block (3A) was a structural unit derived from tricarboxylic acid obtained by reacting the polyamide obtained in the synthesis example with a tri- or higher functional polymerizable monomer (specifically, the polymerizable monomer (c1-1) described below).

[0172] The branching ratio was calculated as follows. Here, the branching ratio is the molar ratio (percentage) of the total of trifunctional or higher functional monomers or trifunctional or higher functional polymers to the total of bifunctional monomers or polymers and trifunctional or higher functional monomers or polymers. In this example, the branching ratio was calculated as the molar ratio (percentage) of trifunctional structural units to the total of bifunctional structural units and trifunctional structural units. The results are shown in Table 1.

[0173] [4. Average Molecular Weight Between Branch Points in Block Copolymer] The polyamide block copolymers obtained in the examples were used as samples, and the average molecular weight between branch points was determined from the amounts charged during polymerization. Specifically, the molecular weight of the structural unit formed by linking polymer block (A) and polymer block (B) and optionally containing linking group (C) was calculated by dividing the molecular weight by the molar ratio of polymerizable monomer (c1) having three or more reactive functional groups or polymer block (3A) (the value obtained by converting the above branching ratio to a decimal).

[0174] [5. Evaluation of Heat Resistance: Measurement of Melting Point] 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 calorimeter "DSC25" manufactured by TA Instruments. The melting points were measured in accordance with ISO 11357-3 (2011, 2nd edition). Specifically, in a nitrogen atmosphere, the sample was heated from 30°C to 300°C at a rate of 10°C / min, 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 again raised to 300°C at a rate of 10°C / min was taken as the melting point (°C). If there were multiple melting peaks, the peak temperature of the highest melting peak was taken as the melting point (°C).

[0175] [6. Evaluation of molding processability: batch foaming test] (6-1. Batch foaming test) Using the polyamide block copolymers obtained in the examples and comparative examples as samples, a batch foaming test was carried out under predetermined foaming conditions as follows.

[0176] (Batch foaming test under first foaming condition) First, a film having a thickness of 1 mm was prepared from the polyamide block copolymer by melt pressing (pressing temperature: melting point + 20°C). A disk-shaped specimen (13 mm in diameter) was punched out from this film and placed in a pressure vessel. Next, the air inside the pressure vessel was replaced with nitrogen gas as the treatment gas. After completion of the replacement, the valve of the pressure vessel was closed. Thereafter, the atmosphere inside the pressure vessel was pressurized while being heated in an electric furnace, and after reaching a treatment temperature of 270°C and a treatment pressure of 40 MPa, these were maintained. This allowed the gas inside the pressure vessel to be impregnated into the polyamide block copolymer. After 4 hours, the valve was opened while maintaining the predetermined temperature, and the pressure was rapidly released. After the pressure was released, the electric furnace was stopped and the pressure vessel was cooled by blowing air. After cooling, a foam was recovered from the pressure vessel as a treated specimen.

[0177] (Batch Foaming Test Under Second Foaming Condition) A batch foaming test was carried out in the same manner as described above, except that the second foaming conditions (treatment gas: nitrogen gas, treatment temperature: 270°C, treatment pressure: 30 MPa) were adopted instead of the first foaming conditions.

[0178] (Batch Foaming Test Under Third Foaming Condition) A batch foaming test was conducted in the same manner as described above, except that the third foaming conditions (treatment gas: carbon dioxide gas, treatment temperature: 270°C, treatment pressure: 30 MPa) were adopted instead of the first foaming conditions.

[0179] (6-2. Measurement of Expansion Ratio) The expansion ratio of the foam was calculated based on the following formula. Note that the density ρ0 (g / cm ３ ) and the apparent density ρ1 (g / cm ) of the foamed body (the above-treated specimen) ３ ) was measured by the submerged weighing method in accordance with JIS Z8807:2012. The calculated expansion ratios are shown in Table 1. Expansion ratio = ρ0 / ρ1

[0180] (6-3. Evaluation) When the expansion ratio calculated above is 1.5 or more, the effect of reducing the specific gravity of the molded body is sufficiently achieved. For this reason, an expansion ratio of 1.5 or more is usually evaluated as having excellent moldability. Therefore, when the expansion ratio is 1.5 or more, preferably 3.0 or more under any of the first, second, and third expansion conditions, the polyamide block copolymer is evaluated as having excellent versatility for the expansion conditions.

[0181] [7. Complex Shear Viscosity η0] Using the polyamide block copolymers obtained in the Examples and Comparative Examples as samples, first test pieces were prepared in accordance with JIS K7244-10:2005. The complex shear viscosity of each test piece was measured using a parallel plate oscillatory rheometer "DHR" manufactured by TA Instruments. The complex shear viscosity was measured in accordance with JIS K7244-10:2005. Specifically, the frequency dependency was measured on the first test piece in a thermal equilibrium state at a temperature 30°C higher than the melting point. To measure the frequency dependency, the angular frequency was varied from 0.0628 to 628 rad·s. －１ The angular frequency was changed in a logarithmic sweep up to 6.28 rad·s －１ The complex shear viscosity value η0 was calculated.

[0182] [8. Strain Hardening Parameter H] (8-1. Measurement of First Viscosity η1) Each of the polyamide block copolymers obtained in the Examples and Comparative Examples was used as a sample to prepare a second test piece having a thickness of 0.8 mm, a long side of 20 mm, and a short side of 10 mm. For each test piece, an extensional test was performed using a parallel plate oscillatory rheometer "DHR" manufactured by TA Instruments and a measuring jig "SER2 Extensional" manufactured by the same company, to measure the extensional viscosity.

[0183] Specifically, a 0.8 mm thick sample film prepared by hot press molding a polyamide block copolymer was cut into a 20 mm × 10 mm rectangle to prepare a second test piece. The test piece was then set in the jig and brought to thermal equilibrium at a temperature 10°C higher than the melting point. An extension test was then carried out along the long side of the second test piece at a strain rate of 1.0 / s to measure the extensional viscosity.

[0184] From the measurement results and the condition of the second test piece after the measurement, the maximum attainable elongational viscosity (Pa s) was determined based on the following criteria 1 or 2, and this was designated as the first viscosity η1. Criterion 1: If the second test piece broke before the true strain (logarithmic strain) reached 3.8, the elongational viscosity value at the true strain at which the second test piece broke was designated as the maximum attainable elongational viscosity. Criterion 2: If the second test piece did not break before the true strain (logarithmic strain) reached 3.8, the elongational viscosity value at a true strain of 3.8 was designated as the maximum attainable elongational viscosity.

[0185] (8-2. Calculation of second viscosity η2) (8-2-1. Dynamic viscoelasticity measurement) Using each of the polyamide block copolymers obtained in the examples and comparative examples as a sample, a third test piece was prepared in accordance with JIS K7244-10:2005. The shape of the third test piece was the same as that of the first test piece. For each test piece, the shear storage modulus G' [Pa] and the shear loss modulus G" [Pa] were measured using a parallel plate oscillatory rheometer "DHR" manufactured by TA Instruments. The shear storage modulus and the shear loss modulus were obtained by performing dynamic viscoelasticity measurement on the third test piece in a thermal equilibrium state at a temperature 10°C higher than the melting point in accordance with JIS K7244-10:2005.

[0186] (8-2-2. Substitution into Equation) Next, the value of the second viscosity η2 was calculated using the following equation. The following equation represents the tripled shear viscosity growth function when the plastic exhibits linear viscoelasticity, and was cited from Non-Patent Document 1 (J. Soc. Rheol. Jpn 4 (1976) 166). 3η ＋ (t)=3t[G"(ω)+1.12G'(ω / 2)-0.200G'(ω)]

[0187] Specifically, in the above formula, the extension time t1 (s) when the maximum attained extensional viscosity η1 is shown is substituted as time t, and the reciprocal of t1 (i.e., ω = 1 / t1) is used as the angular frequency ω, and the values ​​of the shear storage modulus and shear loss modulus obtained by measurement at the corresponding time are substituted, whereby 3η ＋ The value of (t1) was determined, and this value was used as the value of the second viscosity η2.

[0188] The value of the second viscosity η2 is equal to three times the viscosity value (Pa s) obtained by substituting the extension time t1 (s) at which the maximum attained extensional viscosity η1 is reached as time t in the shear viscosity growth function η(t) when the polyamide block copolymer exhibits linear viscoelasticity.

[0189] (8-3. Calculation of strain hardening parameter H) The strain hardening parameter H is the ratio of the first viscosity η1 to the second viscosity η2, that is, it is expressed by the following formula (1): H=η1 / η2 (1) The first viscosity η1 obtained in 8-1 above and the second viscosity η2 obtained in 8-2 above were substituted into the above formula (1) to obtain the strain hardening parameter H. The results are shown in Table 1.

[0190] <Materials> The materials used in the examples and comparative examples are as follows.

[0191] <Polymer Block (A)> To form polymer block (A), a polyamide obtained in the following synthesis example was used. [Synthesis Example] A polyamide was produced from a mixture of 1,9-nonanediamine / 2-methyl-1,8-octanediamine (molar ratio 50 / 50), terephthalic acid, benzoic acid, sodium hypophosphite monohydrate, and distilled water according to the method described in Example 1 of Patent Document 3 (Japanese Patent No. 3242781). The resulting polyamide was a semi-aromatic polyamide. The glass transition temperature of this semi-aromatic polyamide was 111°C. The number average molecular weight Mn of this semi-aromatic polyamide was 2000.

[0192] <Polymerizable Monomer (c2)> Terephthalic acid: manufactured by Tokyo Chemical Industry Co., Ltd.

[0193] <Polymerizable monomer (c1-1)> Trimesic acid: manufactured by Tokyo Chemical Industry Co., Ltd. <Polymer block (B)> Polyether diamine: "Jeffamine (registered trademark) ED-900" manufactured by Sigma-Aldrich (glass transition temperature: -70°C, number average molecular weight Mn: 900) <Polymerizable monomer (c1-2)> Triamine: "Jeffamine (registered trademark) T-403" manufactured by Sigma-Aldrich (trimethylolpropane poly(oxypropylene) triamine, number average molecular weight Mn: 440)

[0194] Example 1 64.00 g (32.00 mmol) of the polyamide constituting the polymer block (A), 4.96 g (29.9 mmol) of terephthalic acid as the polymerizable monomer (c2), and 0.72 g (3.4 mmol) of trimesic acid as the polymerizable monomer (c1-1) were added to a 200 mL flask equipped with an apparatus capable of distilling off generated volatile components. While stirring the contents under a nitrogen stream of 200 mL / min, the temperature of the molten contents was raised to 280°C and maintained at this temperature for 1 hour. This resulted in a mixture of a bifunctional polymer derived from polyamide and terephthalic acid (the polymer constituting polymer block (2A)) and a trifunctional polymer derived from polyamide and trimesic acid (the polymer constituting polymer block (3A)). It was confirmed that polyamides terminated with monoamines and monocarboxylic acids (i.e., polyamides monofunctional with respect to diamines) were absent or present in amounts below the detection limit. １ This was confirmed by H-NMR.

[0195] Subsequently, 33.21 g (36.90 mmol) of the polyetherdiamine constituting polymer block (B) was added to the flask. Thereafter, the contents were stirred for 1 hour while the temperature was maintained at 280° C. and the distillate was removed. The polyamide block copolymer obtained as a result of the reaction was then removed from the flask.

[0196] The polyamide block copolymer according to Example 1 was subjected to the above-described measurements and evaluations. The results are shown in Table 1. The number average molecular weight Mn of the polyamide block copolymer was 70,000. The values ​​used to calculate the value of the second viscosity η2 of the polyamide block copolymer according to Example 1 were as follows: t1 = 3.47 G"(ω) = 4800 G'(ω / 2) = 1900 G'(ω) = 2910

[0197] Example 2 A polyamide block copolymer according to Example 2 was obtained in the same manner as in Example 1, except that the amounts of materials used in the reaction were changed as shown in Table 1. The obtained polyamide block copolymer was then subjected to measurements and evaluations in the same manner as in Example 1. The results are shown in Table 1. The number average molecular weight Mn of the polyamide block copolymer was 46,000. The values ​​used to calculate the value of the second viscosity η2 of the polyamide block copolymer according to Example 2 were as follows: t1 = 3.14 G"(ω) = 9650 G'(ω / 2) = 9780 G'(ω) = 12900

[0198] Example 3: 55.00 g (27.50 mmol) of polyamide constituting polymer block (A) and 4.75 g (28.59 mmol) of terephthalic acid as polymerizable monomer (c2) were added to a 200 mL flask equipped with a device capable of distilling off generated volatile components. While stirring the contents under a nitrogen gas flow of 200 mL / min, the temperature of the molten contents was raised to 280°C and maintained at this temperature for 1 hour. This resulted in a bifunctional polymer derived from polyamide and terephthalic acid (polymer constituting polymer block (2A)). It was confirmed that polyamides terminated with monoamine and monocarboxylic acid (i.e., polyamides monofunctional with respect to diamine) were not present or present in amounts below the detection limit. １ This was confirmed by H-NMR.

[0199] Subsequently, 24.50 g (27.22 mmol) of the polyether diamine constituting the polymer block (B) and 0.81 g (1.8 mmol) of the triamine as the polymerizable monomer (c1-2) were added to the flask. Thereafter, the contents were stirred for 1 hour while maintaining the temperature at 280°C and further removing the distillate. The polyamide block copolymer obtained as a result of the reaction was then removed from the flask.

[0200] The obtained polyamide block copolymer was then subjected to measurement and evaluation in the same manner as in Example 1. The results are shown in Table 1. The number average molecular weight Mn of the polyamide block copolymer was 63,000. The values ​​used to calculate the value of the second viscosity η2 of the polyamide block copolymer according to Example 3 were as follows: t1 = 3.27 G"(ω) = 1000 G'(ω / 2) = 277 G'(ω) = 474

[0201] Examples 4 and 5 Polyamide block copolymers according to Examples 4 and 5 were obtained in the same manner as in Example 3, except that the amounts of materials used in the reaction were changed as shown in Table 1. The obtained polyamide block copolymers were then subjected to measurement and evaluation in the same manner as in Example 1. The results are shown in Table 1. The number average molecular weight Mn of the polyamide block copolymer according to Example 4 was 69,000, and the number average molecular weight Mn of the polyamide block copolymer according to Example 5 was 52,000.

[0202] The values ​​used to calculate the value of the second viscosity η2 of the polyamide block copolymer according to Example 4 were as follows: t1 = 3.47 G″(ω) = 9210 G′(ω / 2) = 5820 G′(ω) = 8320

[0203] The values ​​used to calculate the value of the second viscosity η2 of the polyamide block copolymer according to Example 5 were as follows: t1 = 3.47 G"(ω) = 18900 G'(ω / 2) = 15500 G'(ω) = 20800

[0204] Comparative Example 1: 64.00 g (32.00 mmol) of polyamide constituting the polymer block (A) and 5.53 g (33.29 mmol) of terephthalic acid as polymerizable monomer (c2) were added to a 200 mL flask equipped with a device capable of distilling off generated volatile components. While stirring the contents under a nitrogen gas flow of 200 mL / min, the temperature of the molten contents was raised to 280°C and maintained at this temperature for 1 hour. This resulted in a bifunctional polymer derived from polyamide and terephthalic acid. It was confirmed that polyamides terminated with monoamine and monocarboxylic acid (i.e., polyamides monofunctional with respect to diamine) were not present or present in amounts below the detection limit. １ This was confirmed by H-NMR.

[0205] Subsequently, 31.68 g (35.20 mmol) of the polyetherdiamine constituting polymer block (B) was added to the flask. Thereafter, the contents were stirred for 1 hour while the temperature was maintained at 280° C. and the distillate was removed. The polyamide block copolymer obtained as a result of the reaction was then removed from the flask.

[0206] The obtained polyamide block copolymer was then subjected to measurement and evaluation in the same manner as in Example 1. The results are shown in Table 1. The number average molecular weight Mn of the polyamide block copolymer was 78,000. The values ​​used to calculate the value of the second viscosity η2 of the polyamide block copolymer according to Comparative Example 1 were as follows: t1 = 3.53 G"(ω) = 551 G'(ω / 2) = 66.9 G'(ω) = 127

[0207]

[0208] The results in Table 1 show that the polyamide block copolymers obtained in Examples 1 to 5 had excellent heat resistance, with melting points of 230° C. or higher. One reason for this is thought to be that the polyamide block copolymers contain 50 mol % or more of structural units derived from semi-aromatic polyamide, thereby exhibiting the high heat resistance derived from the semi-aromatic polyamide.

[0209] In addition, the results in Table 1 indicate that the polyamide block copolymers obtained in Examples 1 to 5 gave foams with higher expansion ratios than the polyamide block copolymer obtained in Comparative Example 1, and therefore had excellent moldability. Furthermore, as shown in Table 1, the polyamide block copolymers that gave foams with high expansion ratios had in common the complex shear viscosity η0 of 500 Pa s or more and the strain hardening parameter H of 3.0 or more. These facts suggest that the polyamide block copolymers, which have high melt viscosity and exhibit strong strain hardening during molding, contribute to preventing the coalescence and collapse of bubbles that may occur during molding, thereby achieving excellent moldability.

[0210] From the above, as exemplified in Examples 1 to 5, it was found that by including a semi-aromatic polyamide in the polymer block (A) and controlling the complex shear viscosity η0 and strain hardening parameter H of the polyamide block copolymer, it is possible to provide a polyamide block copolymer having an excellent balance between heat resistance and moldability.

[0211] The polyamide block copolymer and polyamide block copolymer composition of this embodiment have the property of an excellent balance between heat resistance and moldability, and can be used in a wide range of fields where such properties are required. For example, the polyamide block copolymer and polyamide block copolymer composition of this embodiment can be used as various part materials such as electrical and electronic components, automotive parts, industrial material parts, industrial parts, daily necessities, household goods, sports parts, leisure parts, and medical parts. The polyamide block copolymer and polyamide block copolymer composition of this embodiment can be particularly applied to hollow molded parts by blow molding, hose and tubular parts and films and sheets by extrusion molding, lightweight components and insulating materials by injection and / or extrusion foam molding, and as additives for resin modification. The polyamide block copolymer and polyamide block copolymer composition of this embodiment can also be applied to molded articles by injection molding, blow molding, press molding, extrusion molding, calendar molding, vacuum forming, or pressure molding.

Claims

1. A polyamide block copolymer comprising a polymer block (A) having a glass transition temperature of more than 20°C and a polymer block (B) having a glass transition temperature of 20°C or less, wherein the polymer block (A) contains 50 mol% or more of structural units derived from a semi-aromatic polyamide, and wherein the polyamide block copolymer is: A first test piece of the polyamide block copolymer is measured in accordance with JIS K7244-10:2005 using a parallel plate oscillatory rheometer at a temperature 30°C higher than the melting point and an angular frequency of 0.0628 to 628 rad·s －１ The complex shear viscosity η0 measured while changing in a logarithmic sweep up to an angular frequency of 6.28 rad s －１ and a strain hardening parameter H, which indicates the ratio of a first viscosity η1 to a second viscosity η2, as expressed by the following formula (1): H=η1 / η2 (1) (in the formula (1), the first viscosity η1 is the maximum attainable elongational viscosity (Pa s) obtained when an elongation test is performed along the long side direction on a second test piece of the polyamide block copolymer having a thickness of 0.8 mm, long sides of 20 mm, and short sides of 10 mm, at a temperature 10°C higher than the melting point and at a strain rate of 1.0 / s; and the second viscosity η2 is three times the viscosity value (Pa s) obtained when the elongation time t1 (s) at which the maximum attainable elongational viscosity η1 is exhibited is substituted for time t in a shear viscosity growth function η(t) when the polyamide block copolymer exhibits linear viscoelasticity).

2. The polyamide block copolymer according to claim 1, wherein the strain hardening parameter H is 3.0 or greater.

3. The polyamide block copolymer according to claim 1, wherein the polymer block (B) is selected from structural units derived from polyether polyol, polyester polyol, polycarbonate polyol, polysiloxane polyol, amine derivatives thereof, or carboxyl derivatives thereof, and combinations thereof.

4. The polyamide block copolymer according to claim 1, wherein the polymer block (A) and the polymer block (B) are bonded directly or indirectly via an amide bond.

5. The polyamide block copolymer of claim 1, which is a branched polymer.

6. The polyamide block copolymer according to claim 1, which contains a linking group (C) that indirectly bonds the polymer block (A) and the polymer block (B), and the linking group (C) contains a structural unit (C-1) derived from a polymerizable monomer (c1) having three or more reactive functional groups.

7. The polyamide block copolymer according to claim 6, wherein the polymerizable monomer (c1) is a polyamine having three or more amino groups.

8. The polyamide block copolymer according to claim 7, wherein the polyamine has a polyether structure as a repeating unit in its main chain.

9. The polyamide block copolymer according to claim 6, wherein the linking group (C) contains a structural unit (C-2) derived from a bifunctional polymerizable monomer (c2).

10. The polyamide block copolymer of claim 1, wherein the strain hardening parameter H is 50 or less.

11. A polyamide block copolymer composition comprising the polyamide block copolymer according to any one of claims 1 to 10.

12. A molded article containing the polyamide block copolymer according to any one of claims 1 to 10.

13. The molded article according to claim 12, which is a foam.

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