Polyamide-based elastomer and production method therefor

Abstract

A polyamide-based elastomer according to the present invention comprises a hard segment comprising a polyamide structure (A) and a constituent unit (D) derived from an iminodialkanoic acid compound (d) represented by general formula (I) and a soft segment comprising a polyether structure (B), wherein the constituent unit (D) is contained in an amount of 0-0.50 parts by mass, excluding 0 part by mass, per 100 parts by mass of the hard segment. (In general formula (I), R1 and R2 each independently represent a C2-20 alkylene group.)

Description

Polyamide elastomer and method for producing same

[0001] The present invention relates to a polyamide elastomer.

[0002] Polyamide elastomers with a polyether structure are used in automobile parts, peripheral parts for electronic devices, battery materials, packings, sealing materials, etc. because of their excellent properties of high elasticity, transparency, elongation recovery, and melt moldability.

[0003] A polyamide-based elastomer having a polyether structure has a polyamide structure as a hard segment and a polyether structure as a soft segment. Patent Documents 1 to 3 describe laminates having a layer of a polyamide-based elastomer and a layer of another elastomer or polyurethane resin. Patent Document 1 describes that blending a polyamide resin and a modified polypropylene resin with a polyamide-based elastomer provides strength, rigidity, and impact resistance in addition to adhesion to a thermoplastic resin elastomer layer. Patent Document 2 describes that a polyamide-based layer containing a polyamide-based elastomer and a thermoplastic polyurethane (TPU)-based layer have good adhesion and impact resistance. Patent Document 3 describes that a polyamide-based elastomer containing structural units derived from a branched diamine compound has good adhesion to thermoplastic polyurethane and also possesses mechanical properties. Patent Document 4 describes that a polyamide-based elastomer having a specific combination of structural units in the hard segment has a low melting point and excellent material strength.

[0004] JP 2008-106249 A JP 2009-029142 A WO 2007 / 145324 A JP 2022-77106 A

[0005] However, there is room for further study to ensure that polyamide-based elastomers alone have a structure with the appropriate flexibility required for use as molded articles. Furthermore, polyamide-based elastomers are required to have moldability, as well as heat resistance and low-temperature properties depending on the application of the molded article. Furthermore, when used as a layer in a laminate, adhesion to thermoplastic resins is required. Therefore, an object of the present invention is to provide a polyamide-based elastomer that has appropriate flexibility and exhibits good moldability, heat resistance, low-temperature properties, and adhesion to thermoplastic resins.

[0006] The present invention relates to, for example, the following items [1] to

[25] : [1] A polyamide-based elastomer comprising a hard segment containing a polyamide structure (A) and a structural unit (D) derived from an iminodialkanoic acid compound (d) represented by the following general formula (I), and a soft segment containing a polyether structure (B), in which the structural unit (D) is more than 0 part by mass and not more than 0.50 parts by mass per 100 parts by mass of the hard segment: (In general formula (I), R １ and R ２ are each independently an alkylene group having 2 to 20 carbon atoms.) [2] The polyamide-based elastomer of [1], wherein the structural unit (D) accounts for more than 0 mass% and less than 0.22 mass% of all structural units of the polyamide-based elastomer (100 mass%). [3] The polyamide-based elastomer of [1] or [2], wherein the polyamide structure (A) comprises a structural unit derived from at least one selected from the group consisting of an aminocarboxylic acid compound and a lactam compound. [4] The polyamide-based elastomer of any of [1] to [3], wherein the mass ratio of the hard segment to the soft segment is hard segment / soft segment = 95 / 5 to 20 / 80. [5] The polyamide-based elastomer of any of [1] to [4], wherein the polyether structure (B) comprises an XYX triblock polyether represented by the following general formula (5): (wherein x represents an integer of 1 to 20, y represents an integer of 4 to 50, and z represents an integer of 1 to 20.) [6] The polyamide-based elastomer according to any of [1] to [5], wherein the hard segment contains a structural unit (C) derived from a dicarboxylic acid compound (c) that does not contain an imino group. [7] The polyamide-based elastomer according to any of [1] to [5], wherein the polyamide structure (A) has structural units derived from an aminocarboxylic acid compound represented by the following general formula (1) and / or a lactam compound represented by the following general formula (2), the polyether structure (B) has structural units derived from an XYX triblock polyether diamine compound represented by the following general formula (3), and further has structural units (C) derived from a dicarboxylic acid compound represented by the following general formula (4) and structural units (D) derived from an iminodialkanoic acid compound (d) represented by the above general formula (I). [In the formula, R ３ represents a linking group containing a hydrocarbon chain. [In the formula, R ３ represents a linking group containing a hydrocarbon chain. [In the formula, x represents an integer of 1 to 20, y represents an integer of 4 to 50, and z represents an integer of 1 to 20.] [In the formula, R ４represents a linking group containing a single bond or a hydrocarbon chain and not containing an imino group.] [8] The polyamide elastomer according to any one of [1] to [7], which has a melting point of 136.0°C or higher as determined from the endothermic peak of melting when heated to 210°C at a rate of 10°C / min using a differential scanning calorimeter. [9] The polyamide elastomer according to any one of [1] to [8], which has a tensile modulus of elasticity of 91 to 1100 MPa as measured in accordance with ISO-527.

[10] A method for producing a polyamide elastomer according to any one of [1] to [9], comprising: (Step 1) ring-opening polymerization of a lactam compound in the presence of any dicarboxylic acid (c) not containing an imino group at a polymerization temperature of 150 to 350°C and a polymerization pressure of 0.1 to 5.0 MPa to produce a polyamide prepolymer having the polyamide structure (A), the structural unit (D), and the optional structural unit (C); and (Step 2) reacting a polyether compound having the polyether structure (B) with the polyamide prepolymer obtained in Step 1.

[11] A method for producing a polyamide elastomer according to any one of [1] to [9], comprising: (Step 1) ring-opening polymerization of a lactam compound in the presence of the iminodialkanoic acid compound (d) and any dicarboxylic acid (c) not containing an imino group to produce a polyamide prepolymer having the polyamide structure (A), the structural unit (D), and any structural unit (C); and (Step 2) reacting the polyether compound having the polyether structure (B) with the polyamide prepolymer obtained in Step 2.

[12] A method for producing a polyamide elastomer according to any one of [1] to [9], comprising: (Step 1) polycondensing an aminocarboxylic acid compound in the presence of the iminodialkanoic acid compound (d) and any dicarboxylic acid (c) not containing an imino group to produce a polyamide prepolymer having the polyamide structure (A), the structural unit (D), and any structural unit (C); and (Step 2) reacting a polyether compound having the polyether structure (B) with the polyamide prepolymer obtained in Step 1.

[13] A method for producing a polyamide-based elastomer according to any one of [1] to [9], comprising polymerizing a polyamide-forming monomer, a polyether compound having the polyether structure (B), the iminodialkanoic acid compound (d), and a dicarboxylic acid (c) not containing any imino group.

[14] A layer comprising a polyamide-based elastomer according to any one of [1] to [9].

[15] A laminate comprising a layer (X1) comprising a polyamide-based elastomer according to any one of [1] to [9], and a layer (Y1) having a composition different from that of layer (X1).

[16] The laminate according to

[15] , in which layer (X1) and layer (Y1) are adjacent to each other.

[17] The laminate according to

[15] , in which layer (Y1) comprises at least one resin selected from the group consisting of polyurethane resins, polyamide-based elastomers, polyurethane-based elastomers, polyester-based elastomers, polyolefin-based elastomers, and polystyrene-based elastomers.

[18] A molded article comprising the polyamide-based elastomer of any one of [1] to [9].

[19] A resin composition comprising the polyamide-based elastomer of any one of [1] to [9].

[20] A resin composition comprising the polyamide-based elastomer of

[19] , which contains at least one thermoplastic resin selected from the group consisting of polyamide resins other than polyamide-based elastomers, polyamideimide resins, polyester resins, polyolefin resins, polystyrene resins, halogenated polyolefin resins, (meth)acrylic resins, polyphenylene ether resins, polycarbonate resins, polyacetal resins, thermoplastic polyurethane resins, and ABS resins.

[21] A layer comprising a resin composition comprising the polyamide-based elastomer of

[19] or

[20] .

[22] A laminate comprising a layer (X2) comprising a composition containing the polyamide-based elastomer of

[19] or

[20] , and a layer (Y2) having a composition different from that of the layer (X2).

[23] The laminate of

[22] , in which the layer (X2) and the layer (Y2) are adjacent to each other.

[24] The laminate according to

[22] , wherein the layer (Y2) contains at least one resin selected from the group consisting of a polyurethane resin, a polyamide elastomer, a polyurethane elastomer, a polyester elastomer, a polyolefin elastomer, and a polystyrene elastomer.

[25] A molded article comprising a resin composition containing the polyamide elastomer according to

[19] or

[20] .

[0007] The polyamide elastomer of the present invention has appropriate flexibility and is excellent in moldability, heat resistance, low-temperature properties, and adhesion to thermoplastic resins.

[0008] The present invention provides a polyamide-based elastomer comprising a hard segment including a polyamide structure (A) and a structural unit (D) derived from an iminodialkanoic acid compound (d) represented by the following general formula (I), and a soft segment including a polyether structure (B), in which the amount of the structural unit (D) is more than 0 part by mass and not more than 0.50 parts by mass per 100 parts by mass of the hard segment: (In general formula (I), R １ and R ２ are each independently an alkylene group having 2 to 20 carbon atoms.) In this specification, "more than 0 parts by mass" and "more than 0% by mass" mean to exclude cases where absolutely nothing is included.

[0009] The polyamide elastomer contains a hard segment and a soft segment, the hard segment containing a polyamide structure (A) and a structural unit (D), and the soft segment containing a polyether structure (B).

[0010] In the polyamide elastomer of the present invention, the polyether structure (B) is a soft segment, and the remaining units are usually hard segments. The polyamide structure (A) and the structural unit (D) in the polyamide elastomer of the present invention each serve as a hard segment.

[0011] Examples of polyamide elastomers include polyether ester amide elastomers in which hard segments and soft segments are bonded via ester bonds, and polyether polyamide elastomers in which hard segments and soft segments are bonded via amide bonds. From the viewpoint of exerting the effects of the present invention and from the viewpoint of excellent hydrolysis resistance, polyether polyamide elastomers in which hard segments and soft segments are bonded via amide bonds are preferred.

[0012] <Polyamide structure (A)> The hard segment comprises a polyamide structure (A). The polyamide structure (A) is preferably a polycondensate having a structural unit derived from a polyamide-forming monomer, which is at least one selected from the group consisting of nylon salts composed of diamines and dicarboxylic acids, aminocarboxylic acid compounds, and lactam compounds. Among these, the polyamide-forming monomer is preferably at least one selected from the group consisting of aminocarboxylic acid compounds and lactam compounds, and from the viewpoint of generating the iminodialkanoic acid compound (d) represented by the above general formula (I) during the reaction, a lactam compound is more preferred. Furthermore, when adding an iminodialkanoic acid compound (d), an aminocarboxylic acid compound is more preferred. Note that, in this specification, the structural unit derived from the lactam compound constituting the polyamide structure (A) does not include the structural unit (D) derived from the iminodialkanoic acid compound (d) generated by ring-opening of the lactam compound.

[0013] The aminocarboxylic acid compound is preferably represented by the following general formula (1). [In the formula, R ３ represents a linking group containing a hydrocarbon chain.

[0014] In the above general formula (1), R ３ is preferably a divalent hydrocarbon group containing an aliphatic group, an alicyclic group, and / or an aromatic group having 2 to 20 carbon atoms, more preferably the above hydrocarbon group having 3 to 18 carbon atoms, even more preferably the above hydrocarbon group having 4 to 15 carbon atoms, still more preferably the above hydrocarbon group having 10 to 15 carbon atoms, and particularly preferably an alkylene group having 10 to 15 carbon atoms.

[0015] R ３ The hydrocarbon chain may have a substituent in place of some or all of the hydrogen atoms. Examples of the substituent include a halogen atom such as a fluorine atom, a nitro group, a cyano group, and an alkyloxy group (linear, branched, or cyclic).

[0016] Specific examples of the aminocarboxylic acid compound include aliphatic ω-aminocarboxylic acids having 5 to 20 carbon atoms, such as 6-aminocaproic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid, 10-aminodecanoic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid. These compounds can be used alone or in combination of two or more.

[0017] The lactam compound is preferably represented by the following general formula (2). [In the formula, R ３ represents a linking group containing a hydrocarbon chain.

[0018] In the above general formula (2), R ３ represents R in general formula (1). ３ is the same as:

[0019] Examples of lactam compounds include aliphatic lactams having 4 to 20 carbon atoms, such as γ-butyrolactam, ε-caprolactam, ω-enantholactam, ω-undecalactam, and laurolactam (ω-lauryllactam). These compounds can be used alone or in combination of two or more.

[0020] Among the aminocarboxylic acid compounds and lactam compounds, laurolactam (ω-lauryllactam), 11-aminoundecanoic acid, and 12-aminododecanoic acid are preferred from the viewpoint of dimensional stability, chemical resistance, and mechanical properties due to low water absorption, and laurolactam is more preferred from the viewpoint of by-producing the iminodialkanoic acid compound represented by the above general formula (I).

[0021] Examples of diamines in the nylon salt include diamine compounds such as aliphatic diamines having 2 to 20 carbon atoms, such as ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexane-1,6-diamine, 2,4,4-trimethylhexane-1,6-diamine, and 3-methylpentane-1,5-diamine. Alicyclic and aromatic diamines may also be used. These may be used alone or in combination of two or more.

[0022] The dicarboxylic acid in the nylon salt can be at least one dicarboxylic acid selected from aliphatic, alicyclic, and aromatic dicarboxylic acids, or a derivative thereof, and examples thereof include dicarboxylic acid compounds such as aliphatic dicarboxylic acids having 2 to 20 carbon atoms, such as oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and dodecanedioic acid. These can be used alone or in combination of two or more.

[0023] The lactam compound undergoes ring-opening polymerization, and the aminocarboxylic acid compound and nylon salt undergo polycondensation to form the polyamide structure (A).

[0024] The polyamide structure (A) preferably has carboxyl groups at both ends. In this case, the hard segment contains, in addition to the polyamide structure (A) and the structural unit (D), at least one dicarboxylic acid (c) selected from the group consisting of aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, and aromatic dicarboxylic acids, or a structural unit (C) derived from a derivative thereof (hereinafter also referred to as "structural unit (C)"). Note that the dicarboxylic acid (c) does not contain an imino group.

[0025] A polyamide structure having carboxyl groups at both ends can be obtained by ring-opening polymerization or polycondensation of the polyamide-forming monomer in the presence of dicarboxylic acid (c), which is preferably represented by the following general formula (4):

[0026] [In the formula, R ４ represents a linking group that contains a single bond or a hydrocarbon chain and does not contain an imino group.

[0027] In the above general formula (4), R ４ is preferably a divalent hydrocarbon group containing an aliphatic group, an alicyclic group, and / or an aromatic group having 1 to 20 carbon atoms, more preferably the above hydrocarbon group having 1 to 15 carbon atoms, even more preferably the above hydrocarbon group having 2 to 12 carbon atoms, still more preferably the above hydrocarbon group having 4 to 10 carbon atoms, and particularly preferably an alkylene group having 4 to 10 carbon atoms.

[0028] Specific examples of the dicarboxylic acid (c) include dicarboxylic acids having 2 to 25 carbon atoms, preferably 3 to 22 carbon atoms (R ４ Examples of suitable dimer acids include linear aliphatic dicarboxylic acids having 1 to 20 carbon atoms (e.g., dimerized aliphatic dicarboxylic acids having 14 to 48 carbon atoms (dimer acids) obtained by dimerizing unsaturated fatty acids obtained by fractional distillation of triglycerides, and hydrogenated products thereof (hydrogenated dimer acids); alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid; and aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid. Examples of dimer acids and hydrogenated dimer acids that can be used include those manufactured by Croda under the trade names "Pripol 1004," "Pripol 1006," "Pripol 1009," and "Pripol 1013." These acids can be used alone or in combination of two or more. Among these, adipic acid, sebacic acid, and dodecanedioic acid are preferred.

[0029] The number average molecular weight of the polyamide structure (A) is preferably 300 to 15,000, and from the viewpoint of flexibility and moldability, more preferably 300 to 6,000. In this specification, the number average molecular weight is a value determined by gel permeation chromatography.

[0030] <Polyether Structure (B)> The soft segment contains a polyether structure (B), and the polyether structure (B) contains a polyether unit (b). The polyether unit (b) is preferably a polyoxyalkylene, and the repeating unit in the polyether unit (b) is more preferably an oxyalkylene having 2 to 4 carbon atoms. The alkylene group of the oxyalkylene is preferably a linear or branched alkylene group having 2 to 4 carbon atoms, such as an ethylene group, n-propylene group, i-propylene group, 1-methylethylene group, 2-methylethylene group, n-butylene group, 1-methylpropylene group, 2-methylpropylene group, dimethylethylene group, or ethylethylene group. The constituent units of the polyether unit (b) may be one type alone or two or more types, but two or more types are preferred.

[0031] Specific examples of the polyether unit (b) of the soft segment include polyoxyethylene derived from polyethylene glycol, polyoxypropylene derived from polypropylene glycol, polytetramethylene ether derived from polytetramethylene ether glycol, and XYX triblock polyethers. These can be used alone or in combination of two or more. Examples of XYX triblock polyethers include those having a structure represented by the following general formula (5):

[0032] (In the formula, x represents an integer of 1 to 20, y represents an integer of 4 to 50, and z represents an integer of 1 to 20.)

[0033] In the general formula (5), x and z are each independently preferably an integer of 1 to 18, more preferably an integer of 1 to 16, even more preferably an integer of 1 to 14, and particularly preferably an integer of 1 to 12. Furthermore, y is preferably an integer of 5 to 45, more preferably an integer of 6 to 40, even more preferably an integer of 7 to 35, and particularly preferably an integer of 8 to 30.

[0034] In the unit represented by general formula (5), it is preferable that x and z are in the above ranges from the viewpoint of transparency of the elastomer, it is preferable that y is in the above range from the viewpoint of rubber elasticity, and it is also preferable that x, y, and z are in the above ranges from the viewpoint of toughness of the elastomer.

[0035] The number average molecular weight of the polyether unit (b) is preferably 200 to 6,000, more preferably 650 to 2,000.

[0036] The polyether structure (B) preferably has a terminal hydroxyl group or an amino group, more preferably a polyether diol having hydroxyl groups at both ends and a polyether diamine having amino groups at both ends, and even more preferably a polyether diamine. When both ends are amino groups, the polyether structure (B) has an amino group at the end or both ends of the polyether unit (b). An XYX triblock polyether diamine compound having a polyether structure with amino groups at both ends is represented, for example, by the following general formula (3):

[0037] [In the formula, x represents an integer of 1 to 20, y represents an integer of 4 to 50, and z represents an integer of 1 to 20.]

[0038] In the general formula (3), x and z are each independently preferably an integer of 1 to 18, more preferably an integer of 1 to 16, even more preferably an integer of 1 to 14, and particularly preferably an integer of 1 to 12. Furthermore, y is preferably an integer of 5 to 45, more preferably an integer of 6 to 40, even more preferably an integer of 7 to 35, and particularly preferably an integer of 8 to 30.

[0039] <Structural Unit (D) Derived from Iminodialkanoic Acid Compound (d)> The hard segment contains a structural unit (D) (also referred to as "structural unit (D)") derived from an iminodialkanoic acid compound (d) represented by the following general formula (I):

[0040]

[0041] In the above general formula (I), R １ and R ２ are each independently an alkylene group having 2 to 20 carbon atoms, preferably each independently an alkylene group having 8 to 15 carbon atoms, more preferably each independently an alkylene group having 9 to 11 carbon atoms, and particularly preferably each independently an alkylene group having 11 carbon atoms. The alkylene group may be either linear or branched, but is preferably linear.

[0042] From the viewpoints of elasticity, heat resistance, low-temperature properties, moldability, and adhesiveness, the content of the structural unit (D) is preferably more than 0% by mass and less than 0.22% by mass, more preferably 0.01 to 0.20% by mass, and even more preferably 0.02 to 0.18% by mass, relative to 100% by mass of all structural units of the polyamide-based elastomer.

[0043] From the viewpoints of elasticity, heat resistance, low-temperature properties, moldability, and adhesiveness, the amount of the structural unit (D) derived from the iminodialkanoic acid compound (d) represented by general formula (I) relative to 100 parts by mass of the hard segment comprising the polyamide structure (A) and the structural unit (D) (100 parts by mass of the structural unit (D) derived from the compound represented by general formula (I) / hard segment) is more than 0 part by mass and 0.50 parts by mass or less, preferably 0.005 to 0.46 parts by mass, and more preferably 0.01 to 0.25 parts by mass.

[0044] The iminodialkanoic acid compound (d) represented by general formula (I) has the potential to react with the terminals of the polyamide structure (A), and since it has two COOH groups and one NH group, it is thought that as a compound with three reaction sites, it has the potential to crosslink the polyamide structure (A). Therefore, by setting the mass ratio of the structural unit (D) to the hard segment within the above range, the degree of crosslinking can be made appropriate, and it is thought that the polyamide elastomer has properties such as a good tensile modulus and improved adhesion to different resins without impairing flexibility.

[0045] Methods for introducing the structural unit (D) into a polyamide elastomer include a method of adding an iminodialkanoic acid compound (d) to a raw material and polymerizing it, and / or a method of using a lactam compound as a raw material for the polyamide structure (A). The details of the production method will be described later.

[0046] The mass ratio of the structural unit (D) to the hard segment can be adjusted by adjusting the amount of lactam blended, the polymerization temperature and polymerization pressure (polymerization conditions) during ring-opening polymerization of the lactam, the amount of iminodialkanoic acid compound (d) represented by general formula (I) blended, and the like.

[0047] <Polyamide-Based Elastomer> Examples of the combination of the hard segment and the soft segment include the combinations of the hard segment and the soft segment described above. For example, a combination of polyamide structure (A) / structural unit (D) / structure (B) and a combination of polyamide structure (A) / structural unit (C) / structural unit (D) / structure (B) are preferred, and a combination of polyamide structure (A) / structural unit (D) / XYX triblock polyether structure and a combination of polyamide structure (A) / structural unit (C) / structural unit (D) / XYX triblock polyether structure are particularly preferred.

[0048] A preferred embodiment of the polyamide elastomer is a polymer containing structural units derived from an aminocarboxylic acid compound represented by the general formula (1) and / or a lactam compound represented by the general formula (2), structural units derived from an XYX triblock polyether diamine compound represented by the general formula (3), structural units derived from a dicarboxylic acid compound represented by the general formula (4), and structural units derived from an iminodialkanoic acid compound represented by the general formula (I). That is, the polyamide elastomer preferably has the polyamide structure (A) having structural units derived from an aminocarboxylic acid compound represented by the general formula (1) and / or a lactam compound represented by the general formula (2), the polyether structure (B) having structural units derived from an XYX triblock polyether diamine compound represented by the general formula (3), and further having structural units (C) derived from a dicarboxylic acid compound represented by the general formula (4) and structural units (D) derived from an iminodialkanoic acid compound represented by the general formula (I).

[0049] The ratio (mass ratio) of the hard segments to the soft segments is preferably hard segment / soft segment = 95 / 5 to 20 / 80. Within this range, bleeding from the molded article is easily avoided and sufficient flexibility is easily ensured. The hard segment / soft segment (mass ratio) is more preferably 95 / 5 to 25 / 75, and even more preferably 95 / 5 to 40 / 60.

[0050] In the present invention, the ratio (mass ratio) of hard segments to soft segments is a value calculated based on the amount of the monomer components constituting each segment. Usually, the ratio (mass ratio) of hard segments to soft segments in the obtained polyamide elastomer is equal to the value calculated based on the amount of the monomer components constituting each segment.

[0051] If the hard segment / soft segment (mass ratio) is less than the above range, the crystallinity of the polyamide component may be low, which may be undesirable because mechanical properties such as strength and elastic modulus may be reduced.If the hard segment / soft segment (mass ratio) is greater than the above range, it may be undesirable because the functions and performance of an elastomer, such as rubber elasticity and flexibility, may be less likely to be exhibited.

[0052] The degree of polymerization of the polyamide elastomer is not particularly limited, but the relative viscosity measured at 25°C in accordance with JIS K 6920-2 by dissolving 0.25 g of the polyamide elastomer in 50 ml of special-grade m-cresol is preferably 1.10 to 5.00, more preferably 1.50 to 4.50, and even more preferably 1.50 to 3.00.

[0053] The polyamide elastomer preferably has a melting point of 136.0°C or higher, more preferably 136.0 to 200.0°C, as determined from the endothermic peak of melting when heated to 210°C at a rate of 10°C / min using a differential scanning calorimeter. A melting point within the above range provides excellent heat resistance. The present invention is believed to have a high melting point within the above range due to the hard segment having a polyamide structure, which is a high-melting-point engineering plastic.

[0054] The tensile modulus of the polyamide elastomer measured in accordance with ISO-527 is preferably 91 to 1,100 MPa, more preferably 100 to 1,080 MPa. Within this range, the polyamide elastomer has appropriate flexibility. As described above, it is believed that such appropriate flexibility is achieved by the polyamide elastomer containing the structural unit (D) derived from the iminodialkanoic acid compound represented by general formula (I) in a specific proportion.

[0055] From the viewpoint of flexibility, the hardness (Shore D) of the polyamide elastomer is preferably in the range of 15 to 70, more preferably in the range of 18 to 70, still more preferably in the range of 20 to 70, and particularly preferably in the range of 25 to 70. The hardness (Shore D) is the median value of hardness measurements at five points measured in accordance with ISO 868 using a type D durometer.

[0056] <Method for producing polyamide elastomer> The production of polyamide elastomer can be carried out by a batch system or a continuous system, and a batch system reaction vessel, a single- or multi-vessel continuous reaction apparatus, a tubular continuous reaction apparatus, etc. can be used alone or in appropriate combination.

[0057] The methods for producing polyamide elastomers can be broadly classified into the following four methods, (Production Method 1) to (Production Method 4), depending on the type of monomer that forms the polyamide structure (A) and the method for introducing the structural unit (D) derived from the iminodialkanoic acid compound (d), which is the compound represented by the general formula (I), into the elastomer.

[0058] (Production Method 1) A method for producing a polyamide elastomer, comprising: (Step 1) ring-opening polymerization of a lactam compound in the presence of an optional imino group-free dicarboxylic acid (c) at a polymerization temperature of 150 to 350°C and a polymerization pressure of 0.1 to 5.0 MPa to produce a polyamide prepolymer having a polyamide structure (A), a structural unit (D), and an optional structural unit (C); and (Step 2) reacting a polyether compound having a polyether structure (B) with the polyamide prepolymer obtained in Step 1.

[0059] In step 1 of production method 1, a lactam compound is subjected to ring-opening polymerization. A certain amount of an iminodialkanoic acid compound (d) represented by general formula (I), which is a ring-opened dimer of the lactam compound, is produced. As a result, a polyamide prepolymer is obtained that contains a polyamide structure (A), which is a ring-opened polymer of the lactam, and a structural unit (D) derived from the iminodialkanoic acid compound represented by general formula (I). The ring-opening polymerization can also be carried out in the presence of a dicarboxylic acid (c) that does not contain an imino group. In this case, a polyamide prepolymer can be obtained that further contains a structural unit (C).

[0060] In step 1, the proportion of the structural unit (D) contained in the polyamide prepolymer varies depending on the polymerization temperature and polymerization pressure, and the higher the polymerization temperature and the polymerization pressure, the greater the proportion of the structural unit (D) contained in the polyamide prepolymer tends to be. Therefore, from the viewpoint of controlling the proportion of the structural unit (D) contained in the polyamide elastomer, the ring-opening polymerization is carried out at a polymerization temperature of 150 to 350°C, preferably 250 to 300°C, and a polymerization pressure of 0.1 to 5.0 MPa, preferably 1.0 to 4.0 MPa.

[0061] The polymerization time in step 1 is preferably 2 to 15 hours, more preferably 5 to 12 hours. If the polymerization time is shorter than the above range, the increase in molecular weight is likely to be insufficient, whereas if the polymerization time is longer, coloration due to thermal decomposition or the like is likely to occur. In either case, a polyamide elastomer having the desired physical properties may not be obtained.

[0062] In step 2 of production method 1, the polyamide prepolymer obtained in step 1 is reacted with a polyether compound having a polyether structure (B) to obtain a polyamide elastomer. The polyether compound is preferably a polyether polyamine. Polymerization is preferably carried out at a temperature of 150 to 300°C, more preferably 200 to 250°C.

[0063] (Production Method 2) A method for producing a polyamide elastomer, comprising: (Step 1) ring-opening polymerization of a lactam compound in the presence of an iminodialkanoic acid compound (d) and an optional dicarboxylic acid (c) not containing an imino group to produce a polyamide prepolymer having a polyamide structure (A), a structural unit (D), and an optional structural unit (C); and (Step 2) reacting a polyether compound having a polyether structure (B) with the polyamide prepolymer obtained in Step 2.

[0064] In step 1 of Production Method 2, a lactam compound is subjected to ring-opening polymerization in the presence of an iminodialkanoic acid compound (d) and an optional imino-free dicarboxylic acid (c). A polyamide prepolymer having a polyamide structure (A), a structural unit (D), and an optional structural unit (C) is obtained.

[0065] In step 1, the polymerization temperature is not particularly limited as long as the polymerization proceeds and unnecessary side reactions do not occur. Depending on the temperature and pressure conditions, the iminodialkanoic acid compound (d) represented by general formula (I) is produced, and in production method 2, the proportion of structural unit (D) contained in the polyamide elastomer is also controlled by adding the iminodialkanoic acid compound (d). The polymerization time in step 1 is the same as in step 1 of production method 1.

[0066] In step 2 of production method 2, a polyether compound having a polyether structure (B) is reacted with the polyamide prepolymer obtained in step 1. The polyether compound is preferably a polyether polyamine. At this time, polymerization is carried out at a temperature of preferably 150 to 300°C, more preferably 200 to 250°C.

[0067] (Production Method 3) A method for producing a polyamide elastomer, comprising: (Step 1) polycondensing an aminocarboxylic acid compound in the presence of an iminodialkanoic acid compound (d) and an optional dicarboxylic acid (c) not containing an imino group to produce a polyamide prepolymer having a polyamide structure (A), a structural unit (D), and an optional structural unit (C); and (Step 2) reacting a polyether compound having a polyether structure (B) with the polyamide prepolymer obtained in Step 1.

[0068] In step 1 of production method 3, an aminocarboxylic acid compound is polycondensed in the presence of an iminodialkanoic acid compound (d) and an optional dicarboxylic acid (c) not containing an imino group to obtain a polyamide prepolymer having a polyamide structure (A), a structural unit (D), and an optional structural unit (C). The polymerization temperature is preferably 150 to 350°C, more preferably 180 to 280°C. The proportion of structural unit (D) contained in the polyamide prepolymer can be controlled by adjusting the amount of iminodialkanoic acid compound (d) relative to the aminocarboxylic acid compound. The polymerization time in step 1 is preferably 2 to 15 hours, more preferably 3 to 12 hours.

[0069] In step 2 of production method 3, the polyamide prepolymer obtained in step 1 is reacted with a polyether compound having a polyether structure (B) to obtain a polyamide elastomer. The polyether compound is preferably a polyether polyamine. The polymerization is preferably carried out at a temperature of 150 to 300°C, more preferably 200 to 250°C.

[0070] (Production Method 4) A method for producing a polyamide-based elastomer, comprising polymerizing a polyamide-forming monomer, a polyether compound having a polyether structure (B), an iminodialkanoic acid compound (d) represented by general formula (I), and a dicarboxylic acid (c) not containing any imino group.

[0071] In production method 4, a polyamide-forming monomer, a polyether compound having a polyether structure (B), an iminodialkanoic acid compound (d) represented by general formula (I), and an optional dicarboxylic acid (c) not containing an imino group are reacted all at once to obtain a polyamide elastomer having a polyamide structure (A), a structural unit (D), an optional structural unit (C), and a polyether structure (B). The polyether compound is preferably a polyether polyamine.

[0072] When an aminocarboxylic acid is used as the polyamide-forming monomer, the polyamide can be produced by a method comprising the steps of atmospheric pressure melt polymerization or atmospheric pressure melt polymerization followed by reduced pressure melt polymerization. On the other hand, when a lactam compound, or a compound synthesized from a diamine compound and a dicarboxylic acid compound and / or a salt thereof is used as the polyamide-forming monomer, the polyamide can be produced by a method comprising melt polymerization under a pressure of 0.1 to 5.0 MPa in the presence of an appropriate amount of water, followed by atmospheric pressure melt polymerization and / or reduced pressure melt polymerization.

[0073] (Production Method 5) A method for producing a polyamide elastomer, comprising reacting a polyamide elastomer comprising a hard segment containing a polyamide structure (A) and a soft segment containing a polyether structure (B) with an iminodialkanoic acid compound (d) represented by general formula (I).

[0074] In the production method 5, when the polyamide elastomer is reacted with the iminodialkanoic acid compound (d), the product can also be produced by a method comprising the steps of atmospheric pressure melt polymerization or atmospheric pressure melt polymerization followed by reduced pressure melt polymerization.

[0075] (Others) When producing a polyamide elastomer, monoamines and diamines such as laurylamine, stearylamine, hexamethylenediamine, and metaxylylenediamine, monocarboxylic acids such as acetic acid, benzoic acid, stearic acid, adipic acid, sebacic acid, and dodecanedioic acid, and dicarboxylic acids can be added as needed to adjust the molecular weight or stabilize the melt viscosity during molding. These are preferably added in appropriate amounts so that the relative viscosity of the final elastomer falls within the range of 1.10 to 5.00. The method for measuring the relative viscosity is as described above.

[0076] The amounts of the monoamines, diamines, monocarboxylic acids, dicarboxylic acids, etc. added are preferably within a range that does not impair the properties of the resulting polyamide elastomer.

[0077] When producing a polyamide elastomer, catalysts such as phosphoric acid, pyrophosphoric acid, and polyphosphoric acid can be added as needed, and inorganic phosphorus compounds such as phosphorous acid, hypophosphorous acid, and their alkali metal salts and alkaline earth metal salts can be added to achieve both catalytic and heat-resistant effects. The catalysts may be used alone or in combination of two or more. The amount added is typically 50 to 3,000 ppm by mass based on the raw materials.

[0078] A heat-resistant agent may be used when producing a polyamide elastomer. Organic or inorganic heat-resistant agents can be used depending on the purpose. Examples of organic heat-resistant agents include phenolic compounds, phosphorus compounds, sulfur compounds, and nitrogen compounds. Examples of inorganic heat-resistant agents include copper compounds and potassium halides. The heat-resistant agents may be used alone or in combination of two or more.

[0079] To the polyamide-based elastomer, ultraviolet absorbers, light stabilizers, antioxidants, antistatic agents, lubricants, slip agents, crystal nucleating agents, tackifiers, sealability improvers, anti-fogging agents, mold release agents, plasticizers, pigments, dyes, fragrances, flame retardants, reinforcing materials, and the like can be added within the range where the properties of the polyamide-based elastomer are not impaired.

[0080] <Resin composition containing polyamide-based elastomer> The polyamide-based elastomer can be used together with other thermoplastic resins to form a resin composition. The thermoplastic resin contained in the resin composition containing the polyamide-based elastomer includes at least one selected from the group consisting of polyamide resins other than polyamide-based elastomers, polyamideimide resins, polyester resins, polyolefin resins, polystyrene resins, halogenated polyolefin resins, (meth)acrylic resins, polyphenylene ether resins, polycarbonate resins, polyacetal resins, thermoplastic polyurethane resins, and ABS resins. Among these, at least one selected from the group consisting of polyamide resins other than polyamide-based elastomers, polyvinyl chloride resins, thermoplastic polyurethane resins, and ABS resins is preferred from the viewpoint of compatibility with the polyamide-based elastomer.

[0081] To the resin composition containing a polyamide-based elastomer, ultraviolet absorbers, light stabilizers, antioxidants, antistatic agents, lubricants, slip agents, crystal nucleating agents, tackifiers, sealability improvers, anti-fogging agents, mold release agents, plasticizers, pigments, dyes, fragrances, flame retardants, reinforcing materials, heat resistance agents, and the like can be added within the range where the properties of the resin composition are not impaired.

[0082] A known method can be used to produce a resin composition containing a polyamide elastomer, for example, by dry blending a polyamide elastomer, another thermoplastic resin, and, if necessary, various additives using a tumbler and / or a mixer, or by dry blending them in advance at the concentration to be used during molding and then melt-kneading them, etc. Melt-kneading can be carried out using a kneader such as a single-screw extruder, a twin-screw extruder, a kneader, or a Banbury mixer.

[0083] <Molding and Molded Articles> The polyamide-based elastomer and the resin composition containing the polyamide-based elastomer can be molded into molded articles by known molding methods such as injection molding, extrusion molding, blow molding, vacuum molding, pressure molding, etc. Each molded article can be used for various applications requiring flexibility, such as automobile parts, peripheral parts for electronic devices, battery materials, packing, sealing materials, etc.

[0084] <Laminate> Polyamide-based elastomers and resin compositions containing polyamide-based elastomers have good adhesion to other thermoplastic resins and can be used for laminates. Examples of the laminate include a laminate including at least one layer made of a polyamide-based elastomer and a laminate including at least one layer made of a resin composition containing a polyamide-based elastomer.

[0085] Examples of preferred laminates include a laminate including a layer (X1) made of a polyamide-based elastomer and a layer (Y1) having a different composition from layer (X1), and a laminate including a layer (X2) made of a composition containing a polyamide-based elastomer and a layer (Y2) having a different composition from layer (X2). Layer (X1) and layer (Y1) are preferably adjacent to each other. Layer (X2) and layer (Y2) are preferably adjacent to each other. The thickness of each layer is not particularly limited and can be adjusted depending on the type of polymer constituting each layer, the total number of layers in the laminate, the intended use, and the like. Furthermore, the number of layers in the laminate is two or more, but the total number of layers in the laminate is not particularly limited.

[0086] The layer (Y1) may have a different composition from the layer (X1). Examples of the resin contained in the layer (Y1) include at least one selected from the group consisting of polyurethane resins, polyamide elastomers, polyurethane elastomers, polyester elastomers, polyolefin elastomers, and polystyrene elastomers. From the viewpoint of adhesion to the layer (X1), the resin contained in the layer (Y1) is preferably a polyurethane resin or a polyurethane elastomer.

[0087] The layer (Y2) may have a different composition from the layer (X2). Examples of the resin contained in the layer (Y2) include the same resins as those in the layer (Y1), and preferred examples of the resins include the same resins as those in the layer (Y1).

[0088] Each of the layer (Y1) and the layer (Y2) can contain an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, a lubricant, a slipping agent, a crystal nucleating agent, a tackifier, a sealability improver, an anti-fogging agent, a release agent, a plasticizer, a pigment, a dye, a fragrance, a flame retardant, a reinforcing material, a heat resistance agent, and the like, to the extent that the properties of the layer (Y1) and the layer (Y2) are not impaired.

[0089] Examples of methods for producing laminates include a method using an extruder corresponding to the number of layers or materials, melt extruding and laminating simultaneously inside or outside a die (coextrusion molding method), or a method in which a single layer or a laminate produced by the above method is first produced in advance, and then resins are laminated on the outside in sequence, using an adhesive as necessary to integrate them (coating method). The laminate is preferably produced by a coextrusion molding method in which various materials are coextruded in a molten state, heat-sealed (melt-bonded) together, and the laminate is produced in one step. That is, the method for producing a laminate preferably includes coextrusion molding.

[0090] Furthermore, when the resulting laminate has a complex shape or when a molded article is to be formed by heat bending after molding, in order to remove residual strain in the molded article, the laminate may be heat-treated after formation for 0.01 to 10 hours at a temperature below the lowest melting point of the resins constituting the laminate, thereby obtaining the desired molded article.

[0091] The laminate can be used for purposes such as shoe soles.

[0092] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. Various evaluation methods and materials used are shown below. In the evaluation, ◯ means pass, and × means fail.

[0093] [Physical Property Measurement, Molding, and Evaluation Methods] (1) Quantitation of Iminodidodecanoic Acid-Derived Constitutional Units in Polyamide-Based Elastomer (When Hard Segments Are Derived from Laurolactam and Adipic Acid) 3 mL of hydrobromic acid was added to 0.1 g of polyamide-based elastomer, and the mixture was heated at 140°C for 15 hours to hydrolyze. The mixture was then dissolved in dimethyl sulfoxide (DMSO) and adjusted to a constant volume of 100 mL. The resulting sample solution was subjected to quantitation of iminodidodecanoic acid using a liquid chromatograph / mass spectrometer (LC / MS) manufactured by Agilent Technologies, Inc., using a 0.1% formic acid aqueous solution / acetonitrile mobile phase. The resulting amount was taken as the amount of iminodidodecanoic acid-derived constitutional units contained in the polyamide-based elastomer before hydrolysis.

[0094] (2) Tensile Modulus A polyamide elastomer was preheated at 200°C for 3 minutes using a heat press manufactured by Shinto Metal Industries Co., Ltd., followed by heat pressing at 5 MPa for 1 minute and then cold pressing at 30°C and 5 MPa for 3 minutes to produce an unstretched polyamide elastomer sheet with a thickness of approximately 130 μm. The resulting unstretched polyamide elastomer sheet was cut into a test piece measuring 150 mm in length and 10 mm in width using a sample cutter manufactured by Dumbbell Co., Ltd. The test piece was subjected to a tensile test in accordance with ISO-527 using a Tensilon tensile tester (Shimadzu AG-I, manufactured by Shimadzu Corporation) at 23°C and 50% RH, with a chuck distance of 50 mm and a test speed of 300 mm / min, to measure the tensile modulus.

[0095] The tensile modulus was evaluated according to the following criteria: ◯: 91 to 1100 MPa - moderate flexibility; ×: less than 91 MPa - too soft and lacking in tension; ×: over 1100 MPa - hard and lacking in flexibility.

[0096] (3) Measurement of Melting Point and Crystallization Temperature Using a DSC7020 manufactured by Hitachi High-Tech Science Corporation, 1 mg of polyamide elastomer was heated to 210°C in an aluminum pan under a nitrogen atmosphere and cooled at a rate of 30°C / min. The exothermic peak of crystallization when the temperature was lowered to 30°C and then further increased to 210°C at a rate of 10°C / min was taken as the crystallization temperature (Tc). The endothermic peak of melting when the temperature was lowered to 30°C and then further increased to 210°C at a rate of 10°C / min was taken as the melting point (Tm).

[0097] The crystallization temperature was evaluated according to the following criteria: ◯: 142.0°C or less - the crystallization rate is moderate; ×: over 142.0°C - the crystallization rate is too fast, and molding defects are likely to occur.

[0098] The melting point was evaluated according to the following criteria: ◯: 136.0°C or higher, good heat resistance; ×: less than 136.0°C, poor heat resistance.

[0099] (4) Solid-state dynamic viscoelasticity measurement A polyamide elastomer was preheated at 200°C for 3 minutes using a hot press manufactured by Shinto Metal Industries Co., Ltd., followed by hot pressing at 5 MPa for 1 minute and then cold pressing at 30°C and 5 MPa for 3 minutes to produce an unstretched polyamide elastomer sheet with a thickness of approximately 130 μm. The unstretched polyamide elastomer sheet obtained above was cut into test pieces measuring 38 mm in length and 6 mm in width using a sample cutter manufactured by Dumbbell Co., Ltd. The loss modulus E" of the test pieces was measured using a TA Instruments RSA-G2 dynamic mechanical analyzer (DMA) in tensile mode, with a strain of 0.2% and a frequency of 1 Hz, by increasing the temperature from -135°C to break. The relaxation temperature was taken as the peak temperature of E".

[0100] The peak temperature of E" was evaluated according to the following criteria: ◯: -53.0°C or lower The loss elasticity of the molded product at low temperatures is good. ×: -53.0°C or higher The loss elasticity of the molded product at low temperatures is poor.

[0101] (5) Initial Peel Strength and Average Peel Strength (T-Peel Test) To evaluate adhesion to urethane resins, a T-peel test was performed on a test piece formed by thermally welding two thermoplastic polyurethane sheets together via a polyamide elastomer, as described below. One side of the thermoplastic polyurethane sheet was pre-welded to a polyimide film to prevent the thermoplastic polyurethane sheet from breaking during the test. In this test, BASF Elastollan ET860D50 (hereinafter referred to as TPU(X)) and BASF Elastollan 1164D50TR (hereinafter referred to as TPU(Y)) were used as the thermoplastic polyurethane resins, and the adhesion of the polyamide elastomer to each thermoplastic polyurethane resin was evaluated.

[0102] (Preparation of Test Pieces) A ​​polyamide elastomer was preheated at 200°C for 3 minutes, then heat-pressed at 5 MPa for 1 minute, and then cold-pressed at 30°C and 5 MPa for 3 minutes to prepare an unstretched polyamide elastomer sheet having a thickness of approximately 130 μm using a heat press manufactured by Shinto Metal Industries Co., Ltd. A thermoplastic polyurethane resin was preheated together with one polyimide film using a heat press manufactured by Shinto Metal Industries Co., Ltd. at 250°C for 3 minutes, then heat-pressed at 5 MPa for 1 minute, and then cold-pressed at 30°C and 5 MPa for 3 minutes to prepare a two-layered welded sheet of an unstretched thermoplastic polyurethane sheet and a polyimide film having a thickness of approximately 130 μm. Two of the two-layer welded sheets were sandwiched between one of the unstretched polyamide elastomer sheets, with the thermoplastic polyurethane sheet facing the polyamide elastomer sheet. A release sheet was sandwiched between the two two-layer welded sheets, leaving a 30 mm margin from the edge of the sheet for gripping, preventing adhesion. The remaining surfaces were hot-pressed at 170°C (corresponding to a temperature above the melting point of the polyamide elastomer and below the melting point of the thermoplastic polyurethane) and 5 MPa for 1 minute to obtain a five-layer sheet laminated in the following order: polyimide film / thermoplastic polyurethane sheet / polyamide elastomer sheet / thermoplastic polyurethane sheet / polyimide film. The five-layer sheet was then cut to a width of 10 mm and a length of 200 mm to prepare a test specimen for the T-peel test.

[0103] (T-Peel Test) The test specimens for T-peel tests prepared in the above steps were subjected to a T-peel test at a test speed of 100 mm / min using a Tensilon tensile tester (Shimadzu AG-I, manufactured by Shimadzu Corporation) in an environment of 23°C and 50% RH. The peel strength (N / mm) was calculated by dividing the test force (N) by the width (mm) of the test specimen. The maximum peel strength immediately before the first decrease in peel strength after the start of the test was determined as the initial peel strength, and the average value of the peel strengths over peel distances of 50 mm to 100 mm was determined as the average peel strength.

[0104] The adhesion to TPU (X) was evaluated according to the following criteria: Initial peel strength: ◯: 10.0 N·mm ―１As a result, interfacial peeling occurs between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet, or the substrate of the thermoplastic polyurethane sheet or the polyamide-based elastomer sheet is destroyed, indicating good adhesion between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet. ×: 10.0 N mm ―１ At less than 9.5 N mm, interfacial peeling occurs between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet, and the adhesion between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet is poor. Average peel strength: Good: 9.5 N mm ―１ As a result, interfacial peeling occurs between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet, or the substrate of the thermoplastic polyurethane sheet or the polyamide-based elastomer sheet is destroyed, indicating good adhesion between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet. ×: 9.5 N mm ―１ At temperatures below this, interfacial peeling occurs between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet, and the adhesion between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet is poor.

[0105] The adhesion to TPU (Y) was evaluated according to the following criteria: Initial peel strength: ◯: 8.0 N·mm ―１ As a result, interfacial peeling occurs between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet, or the substrate of the thermoplastic polyurethane sheet or the polyamide-based elastomer sheet is destroyed, indicating good adhesion between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet. ×: 8.0 N mm ―１ At less than 7.5 N mm, interfacial peeling occurs between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet, and the adhesion between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet is poor. Average peel strength: Good: 7.5 N mm ―１ As a result, interfacial peeling occurs between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet, or the substrate of the thermoplastic polyurethane sheet or the polyamide-based elastomer sheet is destroyed, indicating good adhesion between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet. ×: 7.5 N mm ―１At temperatures below this, interfacial peeling occurs between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet, and the adhesion between the thermoplastic polyurethane sheet and the polyamide-based elastomer sheet is poor.

[0106] (6) Regarding the proportions of each structural unit in Table 1, the amount of structural units derived from iminodidodecanoic acid was determined according to (1) when the hard segment was derived from laurolactam and adipic acid, and when the hard segment was derived from 12-aminododecanoic acid and adipic acid, it was calculated as a percentage from the charged amount, taking into account the loss of condensation water. The proportion of structural units other than those derived from iminodidodecanoic acid in the hard segment was calculated as a percentage by subtracting the amount of iminodidodecanoic acid produced or the charged amount taking into account the loss of condensation water from the charged amount of prepolymer. The soft segment was calculated as a percentage from the charged amount of polyetherdiamine. The terminal group used to bond the hard segment and soft segment is considered to be included in the segment having the terminal group. In the table, (A) lactam-derived structural units does not include structural units derived from iminodidodecanoic acid.

[0107] In the examples and comparative examples, the polyether diamine used was ELASTAMINE RT-1000, a product of HUNTSMAN, Inc. It is an XYX triblock polyether diamine represented by the above general formula (3) (x=3, y=9, z=2).

[0108] [Example 1] 16.6680 g of laurolactam, 3.3342 g of adipic acid, and 2.9572 g of pure water were placed in a 21 mm diameter test tube and inserted into an 80 mL autoclave. After the autoclave was purged with nitrogen, it was placed in a salt bath at 270 °C and immersed for 10 hours. The ultimate pressure was 2.0 MPa. After the reaction, the inserted test tube was removed, and a polyamide 12 prepolymer having carboxyl groups at both ends was obtained.

[0109] Next, 7.0339 g of the resulting polyamide 12 prepolymer, 8.3205 g of polyetherdiamine, and 25.8 mg of sodium hypophosphite were placed in a 34 mm diameter polymerization test tube equipped with a stirrer, nitrogen inlet tube, and distillation tube, and the atmosphere was purged with nitrogen. The mixture was then placed in a salt bath at 230°C and immersed for 6 hours at a stirring speed of 30 rpm and a nitrogen inlet rate of 50 mL / min, where atmospheric polymerization was carried out to obtain a polyamide elastomer. After polymerization, the polyamide elastomer was removed from the test tube, cut into pellets, and dried under reduced pressure. The polyamide elastomer was then subjected to the above evaluations. The results are shown in Table 1. As shown in Table 1, the polyamide elastomer contained structural units derived from iminodidodecanoic acid.

[0110] [Example 2] 16.6706 g of laurolactam, 3.3367 g of adipic acid, and 4.4715 g of pure water were charged into a 21 mm diameter test tube and inserted into an 80 mL autoclave. After the autoclave was purged with nitrogen, it was placed in a salt bath at 270 °C and immersed for 10 hours. The ultimate pressure was 3.0 MPa. After the reaction, the inserted test tube was removed, and a polyamide 12 prepolymer having carboxyl groups at both ends was obtained.

[0111] Next, a polyamide-based elastomer was obtained in the same manner as in Example 1, except that 7.0578 g of the obtained polyamide 12 prepolymer, 8.3614 g of polyether diamine, and 24.5 mg of sodium hypophosphite were added, which was then cut into pellets and dried under reduced pressure. The polyamide-based elastomer was subjected to the above-mentioned evaluations. The results are shown in Table 1. As shown in Table 1, the polyamide-based elastomer contained structural units derived from iminodidodecanoic acid.

[0112] [Example 3] 17.6000 g of 12-aminododecanoic acid, 3.3601 g of adipic acid, and 0.0085 g of iminodidodecanoic acid were placed in a 34 mm diameter polymerization test tube equipped with a nitrogen inlet tube and a distillation tube, and the tube was purged with nitrogen. The tube was then placed in a salt bath at 230°C and immersed for 6 hours without stirring at a nitrogen inlet rate of 50 mL / min, whereupon atmospheric pressure polymerization was carried out to obtain a polyamide 12 prepolymer.

[0113] Next, 23.1220 g of polyetherdiamine and 70.4 mg of sodium hypophosphite were added to the polymerization test tube containing the obtained polyamide 12 prepolymer, and a stirrer was inserted before replacing the atmosphere with nitrogen. The test tube was then placed in a salt bath at 230°C, immersed at a stirring speed of 30 rpm and a nitrogen introduction rate of 50 mL / min for 6 hours, and polymerized under atmospheric pressure to obtain a polyamide elastomer. The polyamide elastomer was then cut into pellets and dried under reduced pressure. The above evaluations were carried out using the polyamide elastomer. The results are shown in Table 1.

[0114] [Example 4] 16.6673 g of laurolactam, 3.3336 g of adipic acid, and 4.4735 g of pure water were charged into a 21 mm diameter test tube and inserted into an 80 mL autoclave. After the autoclave was purged with nitrogen, it was placed in a salt bath at 290 °C and immersed for 8 hours. The ultimate pressure was 3.5 MPa. After the reaction, the inserted test tube was removed, and a polyamide 12 prepolymer having carboxyl groups at both ends was obtained.

[0115] Next, a polyamide-based elastomer was obtained in the same manner as in Example 1, except that 7.0165 g of the obtained polyamide 12 prepolymer, 8.2986 g of polyether diamine, and 24.7 mg of sodium hypophosphite were added, which was then cut into pellets and dried under reduced pressure. The polyamide-based elastomer was subjected to the above-mentioned evaluations. The results are shown in Tables 1 and 2. As shown in Table 1, the polyamide-based elastomer contained structural units derived from iminodidodecanoic acid.

[0116] [Example 5] 19.7675 g of laurolactam, 0.2314 g of adipic acid, and 2.3487 g of pure water were charged into a 21 mm diameter test tube and inserted into an 80 mL autoclave. After the autoclave was purged with nitrogen, it was placed in a salt bath at 270 °C and immersed for 10 hours. The ultimate pressure was 2.0 MPa. After the reaction, the inserted test tube was removed, and a polyamide 12 prepolymer having carboxyl groups at both ends was obtained.

[0117] Next, a polyamide-based elastomer was obtained in the same manner as in Example 1, except that 19.1863 g of the obtained polyamide 12 prepolymer, 1.5548 g of polyether diamine, and 18.1 mg of sodium hypophosphite were added, which was then cut into pellets and dried under reduced pressure. The polyamide-based elastomer was subjected to the above-mentioned evaluations. The results are shown in Table 1. As shown in Table 1, the polyamide-based elastomer contained structural units derived from iminodidodecanoic acid.

[0118] [Example 6] 19.7678 g of laurolactam, 0.2324 g of adipic acid, and 4.5744 g of pure water were placed in a 21 mm diameter test tube and inserted into an 80 mL autoclave. After the autoclave was purged with nitrogen, it was placed in a salt bath at 270 °C and immersed for 10 hours. The ultimate pressure was 3.0 MPa. After the reaction, the inserted test tube was removed, and a polyamide 12 prepolymer having carboxyl groups at both ends was obtained.

[0119] Next, a polyamide-based elastomer was obtained in the same manner as in Example 1, except that 14.3927 g of the obtained polyamide 12 prepolymer, 1.1863 g of polyether diamine, and 13.0 mg of sodium hypophosphite were added, which was then cut into pellets and dried under reduced pressure. The polyamide-based elastomer was subjected to the above-mentioned evaluations. The results are shown in Table 1. As shown in Table 1, the polyamide-based elastomer contained structural units derived from iminodidodecanoic acid.

[0120] [Example 7] 19.7683 g of laurolactam, 0.2330 g of adipic acid, and 4.4912 g of pure water were charged into a 21 mm diameter test tube and inserted into an 80 mL autoclave. After the autoclave was purged with nitrogen, it was placed in a salt bath at 290 °C and immersed for 8 hours. The ultimate pressure was 3.5 MPa. After the reaction, the inserted test tube was removed, and a polyamide 12 prepolymer having carboxyl groups at both ends was obtained.

[0121] Next, a polyamide-based elastomer was obtained in the same manner as in Example 1, except that 14.1417 g of the obtained polyamide 12 prepolymer, 1.1769 g of polyether diamine, and 15.4 mg of sodium hypophosphite were added, which was then cut into pellets and dried under reduced pressure. The polyamide-based elastomer was used for the above-mentioned evaluations. The results are shown in Table 1. As shown in Table 1, the polyamide-based elastomer contained structural units derived from iminodidodecanoic acid.

[0122] Example 8 A polyamide 12 prepolymer was obtained in the same manner as in Example 3, except that 21.1600 g of 12-aminododecanoic acid, 0.2225 g of adipic acid, and 0.0297 g of iminodidodecanoic acid were charged.

[0123] Next, a polyamide-based elastomer was obtained in the same manner as in Example 3, except that 1.6123 g of polyetherdiamine and 19.2 mg of sodium hypophosphite were added to the polymerization test tube containing the obtained polyamide 12 prepolymer. The polyamide-based elastomer was cut into pellets and dried under reduced pressure. The polyamide-based elastomer was used for the above evaluations. The results are shown in Table 1.

[0124] Example 9 A polyamide 12 prepolymer was obtained in the same manner as in Example 3, except that 17.6000 g of 12-aminododecanoic acid, 3.3450 g of adipic acid, and 0.0937 g of iminodidodecanoic acid were charged.

[0125] Next, a polyamide-based elastomer was obtained in the same manner as in Example 3, except that 23.1220 g of polyetherdiamine and 70.4 mg of sodium hypophosphite were added to the polymerization test tube containing the obtained polyamide 12 prepolymer. The polyamide-based elastomer was cut into pellets and dried under reduced pressure. The polyamide-based elastomer was used for the above evaluations. The results are shown in Tables 1 and 2.

[0126] Example 10 A polyamide 12 prepolymer was obtained in the same manner as in Example 3, except that 17.5000 g of 12-aminododecanoic acid, 0.9254 g of adipic acid, and 0.0118 g of iminodidodecanoic acid were charged.

[0127] Next, a polyamide-based elastomer was obtained in the same manner as in Example 3, except that 6.5700 g of polyetherdiamine and 60.0 mg of sodium hypophosphite were added to the polymerization test tube containing the obtained polyamide 12 prepolymer. The polyamide-based elastomer was cut into pellets and dried under reduced pressure. The polyamide-based elastomer was used for the above evaluations. The results are shown in Tables 1 and 2.

[0128] Example 11 A polyamide 12 prepolymer was obtained in the same manner as in Example 3, except that 17.5000 g of 12-aminododecanoic acid, 0.9200 g of adipic acid, and 0.0423 g of iminodidodecanoic acid were charged.

[0129] Next, a polyamide-based elastomer was obtained in the same manner as in Example 3, except that 6.5700 g of polyetherdiamine and 60.0 mg of sodium hypophosphite were added to the polymerization test tube containing the obtained polyamide 12 prepolymer. The polyamide-based elastomer was cut into pellets and dried under reduced pressure. The polyamide-based elastomer was used for the above evaluations. The results are shown in Table 1.

[0130] Example 12 As shown in Table 3, 30 g of a polyamide elastomer (manufactured by UBE Corporation) with a Shore D hardness of 55 and having a polyamide structure composed of structural units derived from laurolactam and adipic acid, a hard segment containing structural units derived from a dicarboxylic acid compound, and a soft segment containing structural units derived from a polyetherdiamine containing an XYX triblock polyether, and 0.051 g of iminodidodecanoic acid were placed in a 34 mm diameter polymerization test tube equipped with a nitrogen inlet and distillation tube, and the tube was purged with nitrogen. The mixture was then placed in a metal bath at 230°C and polymerized under atmospheric pressure for 1 hour under a nitrogen atmosphere to obtain a polyamide elastomer having the above structural units as well as structural units derived from iminodidodecanoic acid. The resulting pellets were then cut into pellets and dried under reduced pressure. The results of the evaluations are shown in Table 3.

[0131] Example 13 As shown in Table 3, 30 g of PEBAX® 6333 manufactured by ARKEMA, having a polyamide structure composed of structural units derived from laurolactam and adipic acid, a hard segment containing structural units derived from a dicarboxylic acid compound, and a soft segment composed of structural units derived from a polyether diol, and 0.051 g of iminodidodecanoic acid were placed in a 34 mm diameter polymerization test tube equipped with a nitrogen inlet tube and a distillation tube, and the mixture was purged with nitrogen. The mixture was then placed in a metal bath at 230°C and polymerized under atmospheric pressure for 1 hour under a nitrogen atmosphere to obtain a polyamide elastomer having the above structural units as well as structural units derived from iminodidodecanoic acid. The resulting product was cut into pellets and dried under reduced pressure. The results of the above evaluations are shown in Table 3.

[0132] Comparative Example 1 A polyamide 12 prepolymer was obtained in the same manner as in Example 3, except that iminodidodecanoic acid was not added, and only 17.6000 g of 12-aminododecanoic acid and 3.3616 g of adipic acid were added.

[0133] Next, a polyamide-based elastomer was obtained in the same manner as in Example 3, except that 23.1220 g of polyetherdiamine and 70.4 mg of sodium hypophosphite were added to the polymerization test tube containing the obtained polyamide 12 prepolymer. The polyamide-based elastomer was cut into pellets and dried under reduced pressure. The polyamide-based elastomer was used for the above evaluations. The results are shown in Tables 1 and 2.

[0134] Comparative Example 2 A polyamide 12 prepolymer was obtained in the same manner as in Example 3, except that 17.6000 g of 12-aminododecanoic acid, 3.3428 g of adipic acid, and 0.1065 g of iminodidodecanoic acid were charged.

[0135] Next, a polyamide-based elastomer was obtained in the same manner as in Example 3, except that 23.1220 g of polyetherdiamine and 70.4 mg of sodium hypophosphite were added to the polymerization test tube containing the obtained polyamide 12 prepolymer. The polyamide-based elastomer was cut into pellets and dried under reduced pressure. The polyamide-based elastomer was used for the above evaluations. The results are shown in Tables 1 and 2.

[0136] Comparative Example 3 A polyamide 12 prepolymer was obtained in the same manner as in Example 3, except that iminodidodecanoic acid was not added, and only 17.5000 g of 12-aminododecanoic acid and 0.9275 g of adipic acid were added.

[0137] Next, a polyamide-based elastomer was obtained in the same manner as in Example 3, except that 6.5700 g of polyetherdiamine and 60.0 mg of sodium hypophosphite were added to the polymerization test tube containing the obtained polyamide 12 prepolymer. The polyamide-based elastomer was cut into pellets and dried under reduced pressure. The polyamide-based elastomer was used for the above evaluations. The results are shown in Tables 1 and 2.

[0138] Comparative Example 4 A polyamide 12 prepolymer was obtained in the same manner as in Example 3, except that 17.5000 g of 12-aminododecanoic acid, 0.9109 g of adipic acid, and 0.0940 g of iminodidodecanoic acid were charged.

[0139]

[0140]

[0141]

[0142] In Tables 1, 2, and 3, the proportion of each structural unit is a value when the total structural units of the polyamide-based elastomer containing that structural unit are taken as 100% by mass. As can be seen from Table 1, Examples 1 to 11, which contain structural units derived from iminodidodecanoic acid as structural units, have appropriate flexibility as represented by the tensile modulus, as well as good heat resistance, low-temperature properties, and moldability. Comparative Example 1, in which the hard segment / soft segment (mass ratio) is 1 or less and the structural units do not contain any structural units derived from iminodidodecanoic acid, has a low tensile modulus and is too flexible. Comparative Example 3, in which the hard segment / soft segment (mass ratio) is 1 or more and the structural units do not contain any structural units derived from iminodidodecanoic acid, has poor low-temperature properties. Comparative Example 2, in which the hard segment / soft segment (mass ratio) is 1 or less and the proportion of structural units derived from iminodidodecanoic acid exceeds 0.50 parts by mass per 100 parts by mass of hard segments, has a low tensile modulus, is too flexible, and has a low melting point and poor heat resistance. Comparative Example 4, in which the hard segment / soft segment (mass ratio) is 1 or more and the amount of structural units derived from iminodidodecanoic acid exceeds 0.50 parts by mass per 100 parts by mass of the hard segment, has poor low-temperature properties. Table 2 shows that the Examples show sufficiently good values ​​for both the initial peel strength and the average peel strength, and have good adhesion to urethane resins, whereas the Comparative Examples have poor values ​​for the average peel strength and poor adhesion to urethane resins.

[0143] Polyamide elastomers are used as molded articles by injection molding, extrusion molding, blow molding, vacuum molding, pressure molding, etc., and the molded articles can be used in applications requiring particular flexibility, such as automobile parts, peripheral parts for electronic devices, battery materials, packings, sealing materials, etc. Furthermore, as laminates, they can be used for shoe soles, etc.

Claims

1. A polyamide-based elastomer comprising a hard segment containing a polyamide structure (A) and a structural unit (D) derived from an iminodialkanoic acid compound (d) represented by the following general formula (I), and a soft segment containing a polyether structure (B), wherein the amount of the structural unit (D) is more than 0 parts by mass and 0.50 parts by mass or less per 100 parts by mass of the hard segment. (In the general formula (I), R １ and R ２ are each independently an alkylene group having 2 to 20 carbon atoms.

2. The polyamide-based elastomer according to claim 1, comprising more than 0 mass% and less than 0.22 mass% of the structural unit (D) relative to 100 mass% of all structural units of the polyamide-based elastomer.

3. The polyamide elastomer according to claim 1, wherein the polyamide structure (A) contains a structural unit derived from at least one compound selected from the group consisting of aminocarboxylic acid compounds and lactam compounds.

4. The polyamide-based elastomer according to claim 1, wherein the mass ratio of the hard segment to the soft segment (hard segment / soft segment) is 95 / 5 to 20 / 80.

5. The polyamide elastomer according to claim 1, wherein the polyether structure (B) comprises an XYX triblock polyether represented by the following general formula (5): (In the formula, x represents an integer of 1 to 20, y represents an integer of 4 to 50, and z represents an integer of 1 to 20.) 6. The polyamide elastomer according to claim 1, wherein the hard segment contains a structural unit (C) derived from a dicarboxylic acid compound (c) not containing an imino group.

7. The polyamide elastomer according to claim 1, wherein the polyamide structure (A) has a constituent unit derived from an aminocarboxylic acid compound represented by the following general formula (1) and / or a lactam compound represented by the following general formula (2), the polyether structure (B) has a constituent unit derived from an XYX triblock polyether diamine compound represented by the following general formula (3), and further has a constituent unit (C) derived from a dicarboxylic acid compound represented by the following general formula (4) and a constituent unit (D) derived from an iminodialkanoic acid compound represented by the above general formula (I). [In the formula, R ３ represents a linking group containing a hydrocarbon chain. [In the formula, R ３ represents a linking group containing a hydrocarbon chain. [In the formula, x represents an integer of 1 to 20, y represents an integer of 4 to 50, and z represents an integer of 1 to 20.] [In the formula, R ４ represents a linking group that contains a single bond or a hydrocarbon chain and does not contain an imino group.

8. The polyamide elastomer according to claim 1, which has a melting point of 136.0°C or higher as determined from the endothermic peak of melting when heated to 210°C at a rate of 10°C / min using a differential scanning calorimeter.

9. The polyamide elastomer according to claim 1, which has a tensile modulus of elasticity of 91 to 1100 MPa as measured in accordance with ISO-527.

10. A method for producing a polyamide elastomer according to any one of claims 1 to 9, comprising: (Step 1) ring-opening polymerization of a lactam compound in the presence of any dicarboxylic acid (c) not containing any imino group at a polymerization temperature of 150 to 350°C and a polymerization pressure of 0.1 to 5.0 MPa to produce a polyamide prepolymer having the polyamide structure (A), the structural unit (D) and any structural unit (C); and (Step 2) reacting a polyether compound having the polyether structure (B) with the polyamide prepolymer obtained in Step 1.

11. A method for producing a polyamide elastomer according to any one of claims 1 to 9, comprising: (Step 1) ring-opening polymerization of a lactam compound in the presence of the iminodialkanoic acid compound (d) and any dicarboxylic acid not containing an imino group (c) to produce a polyamide prepolymer having the polyamide structure (A), the structural unit (D) and any structural unit (C); and (Step 2) reacting a polyether compound having the polyether structure (B) with the polyamide prepolymer obtained in Step 2.

12. A method for producing a polyamide elastomer according to any one of claims 1 to 9, comprising: (Step 1) polycondensing an aminocarboxylic acid compound in the presence of the iminodialkanoic acid compound (d) and any dicarboxylic acid not containing an imino group (c) to produce a polyamide prepolymer having the polyamide structure (A), the structural unit (D) and any structural unit (C); and (Step 2) reacting a polyether compound having the polyether structure (B) with the polyamide prepolymer obtained in Step 1.

13. A method for producing a polyamide-based elastomer according to any one of claims 1 to 9, comprising polymerizing a polyamide-forming monomer, a polyether compound having the polyether structure (B), the iminodialkanoic acid compound (d), and a dicarboxylic acid (c) not containing any imino group.

14. A layer comprising the polyamide elastomer according to any one of claims 1 to 9.

15. A laminate comprising a layer (X1) made of the polyamide elastomer according to any one of claims 1 to 9, and a layer (Y1) having a composition different from that of the layer (X1).

16. The laminate according to claim 15, wherein the layer (X1) and the layer (Y1) are adjacent to each other.

17. The laminate according to claim 15, wherein the layer (Y1) contains at least one resin selected from the group consisting of polyurethane resins, polyamide-based elastomers, polyurethane-based elastomers, polyester-based elastomers, polyolefin-based elastomers, and polystyrene-based elastomers.

18. A molded article comprising the polyamide elastomer according to any one of claims 1 to 9.

19. A resin composition comprising the polyamide elastomer according to any one of claims 1 to 9.

20. A resin composition containing the polyamide-based elastomer according to claim 19, which contains at least one thermoplastic resin selected from the group consisting of polyamide resins other than polyamide-based elastomers, polyamideimide resins, polyester resins, polyolefin resins, polystyrene resins, halogenated polyolefin resins, (meth)acrylic resins, polyphenylene ether resins, polycarbonate resins, polyacetal resins, thermoplastic polyurethane resins and ABS resins.

21. A layer made of a resin composition containing the polyamide elastomer according to claim 19.

22. A laminate comprising a layer (X2) made of a composition containing the polyamide elastomer according to claim 19, and a layer (Y2) having a composition different from that of the layer (X2).

23. The laminate according to claim 22, wherein the layer (X2) and the layer (Y2) are adjacent to each other.

24. The laminate according to claim 22, wherein the layer (Y2) contains at least one resin selected from the group consisting of polyurethane resins, polyamide-based elastomers, polyurethane-based elastomers, polyester-based elastomers, polyolefin-based elastomers, and polystyrene-based elastomers.

25. A molded article comprising a resin composition containing the polyamide elastomer according to claim 19.

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