Polyamide resin composition

Abstract

Provided is a polyamide resin composition from which a molded article that is tough and flexible and has excellent impact resistance can be obtained.　The polyamide resin composition according to the present invention contains, in 100 mass% of the polyamide resin composition, 15-35 mass% of a polyamide-based elastomer (A), 40-79 mass% of an aliphatic polyamide resin (B) in which the average number of carbon atoms per one amide group is more than 6, 0.1-35 mass% of an aromatic polyamide resin (C), and 0-10 mass% of an aliphatic polyamide resin (D) in which the average number of carbon atoms per one amide group is not more than 6.

Description

[Technical Field]

[0001] The present invention relates to a polyamide resin composition. [Background technology]

[0002] A polyamide resin composition in which a polyamide elastomer is blended with a polyamide resin for the purpose of improving the flexibility and impact resistance of the polyamide resin has been reported (see Patent Document 1).

[0003] It has been reported that a magnetic material-resin composite material known as a plastic magnet is produced by mixing a magnetic powder into a polyamide resin composition containing this polyamide elastomer (see Patent Document 2).

[0004] Magnetic material-resin composite materials are widely used in office equipment, motors, actuators, sensors, etc. Magnetic material-resin composite materials are required to have excellent magnetic properties, but to achieve this, the magnetic powder needs to be well dispersed even when a large amount of magnetic powder is blended.

[0005] Furthermore, in order to be used in the wide range of applications described above, magnetic material-resin composite materials are required to have good mechanical properties and other physical properties. In order to achieve both moldability and mechanical properties in a magnetic material-resin composite material, a magnetic material-resin composite material containing magnetic powder, polyamide resin, and epoxy compound is known (see Patent Document 3). In order to improve the heat resistance of a magnetic material-resin composite material, a magnetic material-resin composite material containing magnetic powder and aromatic polyamide resin is known (see Patent Document 4). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-352789 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-352792 [Patent Document 3] Japanese Patent Application Laid-Open No. 2009-57524 [Patent Document 4] Japanese Patent Application Laid-Open No. 2003-342468 Summary of the Invention [Problem to be solved by the invention]

[0007] In the magnetic material-resin composite material of Patent Document 3, there is a possibility that a rigid composite resin lacking in flexibility is produced due to the reaction between the amino groups of the polyamide resin and the epoxy groups of the epoxy resin, and therefore it was necessary to set the ratio of terminal carboxyl groups to terminal amino groups of the polyamide resin within a specific range. The magnetic material-resin composite material of Patent Document 4 was poor in flexibility. The polyamide resin composition of Patent Document 1 and the magnetic material-resin composite material of Patent Document 2 were required to have greater toughness.

[0008] An object of the present invention is to provide a polyamide resin composition which has good moldability and from which molded articles having strength, flexibility and excellent impact resistance can be obtained. [Means for solving the problem]

[0009] The present invention includes, for example, the following [1] to [8]. [1] A polyamide resin composition comprising, based on 100% by mass of the polyamide resin composition, 15 to 35% by mass of a polyamide elastomer (A), 40 to 79% by mass of an aliphatic polyamide resin (B) having an average number of carbon atoms per amide group of more than 6, 0.1 to 35% by mass of an aromatic polyamide resin (C), and 0 to 10% by mass of an aliphatic polyamide resin (D) having an average number of carbon atoms per amide group of 6 or less. [2] The polyamide resin composition according to [1], wherein the polyamide elastomer (A) has a polyether structure. [3] Density: 1.02 g / cm 3 The polyamide resin composition according to [1] or [2] above. [4] The polyamide resin composition according to any one of [1] to [3], which has a MFR of less than 15 g / 10 min as measured in accordance with ISO 1133 at 190°C under a load of 1.00 kg. [5] The polyamide resin composition according to any one of [1] to [4], wherein the polyamide elastomer (A) is a polymer containing a structural unit derived from an aminocarboxylic acid compound represented by the following formula (1) and / or a lactam compound represented by the following formula (2), a structural unit derived from an XYX triblock polyether diamine compound represented by the following formula (3), and a structural unit derived from a dicarboxylic acid compound represented by the following formula (4): [ka] [However, R 1 represents a linking group containing a hydrocarbon chain. [ka] [However, R 2 represents a linking group containing a hydrocarbon chain. [ka] [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.] [ka] [However, R 3 represents a linking group containing a hydrocarbon chain, and m is 0 or 1. [6] A molded article made from the polyamide resin composition of any one of [1] to [5]. [7] A magnetic material-resin composite material comprising the polyamide resin composition according to any one of [1] to [5] and magnetic powder. [8][7] Molded product made of magnetic resin composite material. [Effects of the Invention]

[0010] The polyamide resin composition of the present invention has good moldability and can give molded articles that are strong, flexible, and have excellent impact resistance. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention relates to a polyamide resin composition comprising, based on 100% by mass of the polyamide resin composition, 15 to 35% by mass of a polyamide elastomer (A), 40 to 79% by mass of an aliphatic polyamide resin (B) having an average number of carbon atoms per amide group of more than 6, 0.1 to 35% by mass of an aromatic polyamide resin (C), and 0 to 10% by mass of an aliphatic polyamide resin (D) having an average number of carbon atoms per amide group of 6 or less.

[0012] <Polyamide elastomer (A)> The polyamide resin composition contains a polyamide elastomer (A). The polyamide resin composition contains the polyamide elastomer (A), and thus molded articles thereof exhibit excellent flexibility. The polyamide elastomer (A) has hard segments and soft segments, and the hard segments have a polyamide structure. The soft segments of the polyamide elastomer preferably have a polyether structure, and more preferably have structural units derived from a polyetherdiamine compound. Examples of polyamide elastomers having a polyether structure as the soft segment include polyetheresteramide elastomers in which the hard and soft segments are bonded via ester bonds, and polyetherpolyamide elastomers in which the hard and soft segments are bonded via amide bonds. From the viewpoints of exerting the effects of the present invention, excellent hydrolysis resistance, and stability, polyetherpolyamide elastomers in which the hard and soft segments are bonded via amide bonds are preferred.

[0013] The polyamide structure in the hard segment is preferably a polycondensate having a constituent unit derived from at least one polyamide-forming monomer selected from the group consisting of nylon salts composed of diamines and dicarboxylic acids, aminocarboxylic acid compounds represented by the following formula (1), and lactam compounds represented by the following formula (2).

[0014] [ka] [However, R 1 represents a linking group containing a hydrocarbon chain.

[0015] [ka] [However, R 2 represents a linking group containing a hydrocarbon chain.

[0016] In the above formula (1), R 1 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.

[0017] Examples of the aminocarboxylic acid compound (1) 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.

[0018] In equation (2), R 2is preferably a divalent hydrocarbon group containing an aliphatic group, an alicyclic group, and / or an aromatic group having 3 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.

[0019] Examples of the lactam compound (2) include aliphatic lactams having 4 to 20 carbon atoms, such as ε-caprolactam, ω-enantholactam, ω-undecalactam, ω-lauryllactam, and 2-pyrrolidone.

[0020] Among these, ω-lauryllactam, 11-aminoundecanoic acid, and 12-aminododecanoic acid are preferred from the viewpoints of dimensional stability due to low water absorption, chemical resistance, and mechanical properties.

[0021] Examples of diamines in nylon salts include diamine compounds such as aliphatic diamines having 2 to 20 carbon atoms, such as ethylenediamine, trimethylenediamine, tetramethylenediamine, 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.

[0022] As the dicarboxylic acid in the nylon salt, at least one dicarboxylic acid selected from aliphatic, alicyclic and aromatic dicarboxylic acids or derivatives thereof can be used.

[0023] Specific examples of dicarboxylic acids include linear aliphatic dicarboxylic acids having 2 to 25 carbon atoms, such as oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and dodecanedioic acid; 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 dimer acids 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 available from Croda under the trade names "Pripol 1004," "Pripol 1006," "Pripol 1009," and "Pripol 1013."

[0024] The hard segment can also be derived from a polyamide having carboxyl groups at both terminal groups. In this case, the hard segment is also a segment containing a polyamide structure and a structural unit derived from at least one dicarboxylic acid (4) selected from the group consisting of aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, and aromatic dicarboxylic acids.

[0025] [ka] [However, R 3 represents a linking group containing a hydrocarbon chain, and m is 0 or 1.

[0026] As the dicarboxylic acid compound (4), at least one dicarboxylic acid selected from aliphatic, alicyclic and aromatic dicarboxylic acids or derivatives thereof can be used.

[0027] In equation (4), R 3is 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. Specific examples of the dicarboxylic acid compound represented by the above formula (4) include the compounds exemplified as the dicarboxylic acid compound of the nylon salt composed of a diamine compound and a dicarboxylic acid compound.

[0028] A polyamide 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 (4) according to a conventional method. The dicarboxylic acid of the hard segment can be used as a molecular weight modifier.

[0029] The number average molecular weight of the hard segment is preferably 300 to 15000, and from the viewpoint of flexibility and moldability, more preferably 300 to 6000. In this specification, the number average molecular weight is a value determined by gel permeation chromatography.

[0030] The soft segment preferably has a polyether structure, and the constituent unit of the polyether structure is 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 unit of the polyether structure may be one type alone or two or more types, but two or more types are preferred. Specific examples of the polyether structure of the soft segment include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, and XYX triblock polyether. These may be used alone or in combination. The XYX triblock polyether has, for example, a structure represented by the following chemical formula. [ka] (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.)

[0031] In the above 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. A polyetherdiamine compound can be obtained by reacting the terminal of these polyethers with ammonia, etc. The number average molecular weight of the soft segment is preferably 200 to 6,000, and more preferably 650 to 2,000. The XYX triblock polyether diamine compound is represented by, for example, the following formula (3).

[0032] [ka] [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.]

[0033] In the above 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.

[0034] 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. Among these, the combination of a ring-opening polycondensate of lauryllactam / polyethylene glycol, the combination of a ring-opening polycondensate of lauryllactam / dicarboxylic acid-derived structural units / polypropylene glycol, the combination of a ring-opening polycondensate of lauryllactam / dicarboxylic acid-derived structural units / polytetramethylene ether glycol, the combination of a ring-opening polycondensate of lauryllactam / dicarboxylic acid-derived structural units / XYX triblock polyether, and the combination of a 12-aminododecanoic acid-derived structural unit / dicarboxylic acid-derived structural unit / XYX triblock polyether are preferred, and the combination of a 12-aminododecanoic acid-derived structural unit / dicarboxylic acid-derived structural unit / XYX triblock polyether and the combination of a ring-opening polycondensate of lauryllactam / XYX triblock polyether are particularly preferred. In these combinations, the polyether is preferably a polyetherdiamine-derived structural unit.

[0035] The ratio (mass ratio) of the hard segment to the soft segment is preferably hard segment / soft segment = 95 / 5 to 20 / 80. Within this range, bleeding out from the molded product can be easily avoided and sufficient flexibility can be easily ensured. The hard segment / soft segment (mass ratio) is more preferably 95 / 5 to 25 / 75.

[0036] 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 of the obtained polyamide elastomer is equal to the value calculated based on the amount of the monomer components constituting each segment.

[0037] 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 not be readily exhibited.

[0038] Examples of commercially available polyamide elastomers include the "Diamid (registered trademark)" series manufactured by Daicel-Evonik Ltd., the "Pebax" series manufactured by ARKEMA, the "Grilflex (registered trademark) EBG," "Grilflex (registered trademark) ELG," and "Grillon (registered trademark) ELX" manufactured by M-Chemie Japan, and the "UBESTA XPA (registered trademark)" series manufactured by Ube Industries, Ltd.

[0039] Among these, the "UBESTA XPA (registered trademark)" series manufactured by Ube Industries, Ltd. is preferred from the viewpoint of exerting the effects of the present invention and having excellent hydrolysis resistance.

[0040] The polyamide elastomer (A) may be used alone or in combination of two or more kinds.

[0041] The degree of polymerization of the polyamide elastomer (A) 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 particularly preferably 1.50 to 3.00.

[0042] The hardness (Shore D) of the polyamide elastomer (A) is preferably in the range of 15 to 70, more preferably 18 to 70, even more preferably 20 to 70, and particularly preferably 25 to 70, from the viewpoint of flexibility.

[0043] A preferred embodiment of the polyamide elastomer (A) is a polymer containing a structural unit derived from an aminocarboxylic acid compound represented by the above formula (1) and / or a lactam compound represented by the above formula (2), a structural unit derived from an XYX triblock polyether diamine compound represented by the above formula (3), and a structural unit derived from a dicarboxylic acid compound represented by the above formula (4).

[0044] As a preferred embodiment of the method for producing the polyamide elastomer (A), for example, A method comprising the steps of melt-polymerizing three components, i.e., a polyamide-forming monomer, an XYX triblock polyetherdiamine, and a dicarboxylic acid, under increased and / or normal pressure, and, if necessary, further melt-polymerizing under reduced pressure, can be used. Furthermore, a method comprising the steps of simultaneously melt-polymerizing three components, i.e., a polyamide-forming monomer, an XYX triblock polyetherdiamine, and a dicarboxylic acid, under increased and / or normal pressure, and, if necessary, further melt-polymerizing under reduced pressure, can also be used. It is also possible to first polymerize the two components, i.e., the polyamide-forming monomer and the dicarboxylic acid, and then polymerize the XYX triblock polyetherdiamine. A similar method can be used to produce polyamide elastomers having polyether structural units derived from polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc. as soft segments.

[0045] The polyamide elastomer can be produced at a polymerization temperature of preferably 150 to 300° C., more preferably 160 to 280° C., and particularly preferably 180 to 250° C. If the polymerization temperature is lower than the above temperature, the polymerization reaction tends to be slow, whereas if the polymerization temperature is higher than the above temperature, thermal decomposition tends to occur, and a polymer with good physical properties may not be obtained.

[0046] When an ω-aminocarboxylic acid is used as the polyamide-forming monomer, the polyamide elastomer can be produced by a process comprising the steps of atmospheric pressure melt polymerization or atmospheric pressure melt polymerization followed by reduced pressure melt polymerization.

[0047] 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 in the presence of an appropriate amount of water by a method comprising melt polymerization under pressure of 0.1 to 5 MPa, followed by atmospheric melt polymerization and / or reduced pressure melt polymerization.

[0048] Polyamide elastomers can usually be produced in a polymerization time of 0.5 to 30 hours. If the polymerization time is shorter than the above range, the increase in molecular weight tends to be insufficient, while if the polymerization time is longer, coloration due to thermal decomposition tends to occur. In either case, a polyetheramide elastomer having the desired physical properties may not be obtained.

[0049] The production of polyamide elastomers can be carried out by either 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.

[0050] During the production of polyamide elastomers, monoamines and diamines such as laurylamine, stearylamine, hexamethylenediamine, and metaxylylenediamine, and monocarboxylic acids or dicarboxylic acids such as acetic acid, benzoic acid, stearic acid, adipic acid, sebacic acid, and dodecanedioic acid can be added as needed to adjust the molecular weight or stabilize the melt viscosity during molding. The amount of these additives to be used is preferably adjusted so that the relative viscosity of the final elastomer falls within the range of 1.10 to 5.00.

[0051] The amounts of the monoamines, diamines, monocarboxylic acids, dicarboxylic acids, etc. added are preferably set within a range that does not impair the properties of the resulting polyamide elastomer.

[0052] In the production of polyamide elastomers, 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 amount added is usually 50 to 3,000 ppm based on the raw materials.

[0053] The content of the polyamide elastomer (A) in 100% by mass of the polyamide resin composition is 15 to 35% by mass, preferably 15 to 30% by mass, and more preferably 20 to 30% by mass. When the content of the polyamide elastomer (A) is within the above range, a molded product having both flexibility and toughness and excellent impact resistance can be obtained.

[0054] <Aliphatic polyamide resin (B) having an average number of carbon atoms per amide group of more than 6> The polyamide resin composition contains an aliphatic polyamide resin (B) in which the average number of carbon atoms per amide group is greater than 6 (hereinafter, also referred to as "aliphatic polyamide resin (B)"). When the polyamide resin composition contains an aliphatic polyamide resin (B) having an average number of carbon atoms per amide group of more than 6, the molding processability is easily improved, and the flexibility and mechanical properties of the molded article are easily improved. In addition, polyamide resins have low water absorption and are therefore more resistant to hydrolysis than other thermoplastic resins. Aliphatic polyamide resins include aliphatic homopolyamide resins and aliphatic copolyamide resins. Aliphatic homopolyamide resins are polyamide resins consisting of one type of structural unit derived from an aliphatic monomer. Aliphatic homopolyamide resins may be composed of at least one type of lactam and an aminocarboxylic acid, which is a hydrolyzate of the lactam, or may be composed of a combination of one type of diamine and one type of dicarboxylic acid. Aliphatic copolyamide resins are polyamide resins consisting of two or more structural units derived from aliphatic monomers. Aliphatic copolyamide resins are copolymers of two or more types selected from the group consisting of a combination of a diamine and a dicarboxylic acid, and a lactam and an aminocarboxylic acid. Here, a combination of a diamine and a dicarboxylic acid is considered to be one type of monomer, with one type of diamine and one type of dicarboxylic acid being the combination.

[0055] An aliphatic homopolyamide resin having an average number of carbon atoms per amide group greater than 6 means that, when the constituent units are lactam and aminocarboxylic acid, the number of carbon atoms in the hydrocarbon chain of the constituent unit exceeds 6. When the constituent units are a combination of diamine and dicarboxylic acid, the sum of the number of carbon atoms in the hydrocarbon chain of the diamine multiplied by the molar concentration of the diamine in the polyamide and the number of carbon atoms in the hydrocarbon chain of the dicarboxylic acid multiplied by the molar concentration of the dicarboxylic acid in the polyamide exceeds 6. For example, polytetramethylene sebacamide (polyamide 410) is an aliphatic homopolyamide resin in which the average number of carbon atoms per amide group is more than 6 if the tetramethylene diamine content in the polyamide is less than 67 mol %. On the other hand, if the tetramethylene diamine content is 67 mol % or more, it is an aliphatic homopolyamide resin in which the average number of carbon atoms per amide group is 6 or less, as described below.

[0056] An aliphatic copolyamide resin having an average number of carbon atoms per amide group greater than 6 means that the average number of carbon atoms in the copolymer is greater than 6, calculated by calculating the number of carbon atoms per amide group in each structural unit constituting the copolymer as described above, and multiplying the molar concentration of each structural unit in the copolymer by the number of carbon atoms per amide group in each structural unit.

[0057] Aliphatic homopolyamide resins having an average carbon atom number of more than 6 per amide group include polyundecane lactam (polyamide 11), polylauryl lactam (polyamide 12), polytetramethylene dodecamide (polyamide 412), polypentamethylene azelamide (polyamide 59), polypentamethylene sebacamide (polyamide 510), polypentamethylene dodecamide (polyamide 512), and polyhexamethylene suberamide. Polyamide 68, Polyhexamethylene azelamide (Polyamide 69), Polyhexamethylene sebacamide (Polyamide 610), Polyhexamethylene undecamide (Polyamide 611), Polyhexamethylene dodecamide (Polyamide 612), Polyhexamethylene tetradecamide (Polyamide 614), Polyhexamethylene hexadecamide (Polyamide 616), Polyhexamethylene octadecamide (Polyamide 618) , polynonameethylene adipamide (polyamide 96), polynonameethylene suberamide (polyamide 98), polynonameethylene azelamide (polyamide 99), polynonameethylene sebacamide (polyamide 910), polynonameethylene dodecamide (polyamide 912), polydecamethylene adipamide (polyamide 106), polydecamethylene suberamide (polyamide 108), polydecamethylene azelamide (polyamide 109), poly Examples include didecamethylene sebacamide (polyamide 1010), polydodecamethylene dodecamide (polyamide 1012), polydodecamethylene adipamide (polyamide 126), polydodecamethylene suberamide (polyamide 128), polydodecamethylene azelamide (polyamide 129), polydodecamethylene sebacamide (polyamide 1210), polydodecamethylene dodecamide (polyamide 1212), and polyamide 122.

[0058] Aliphatic copolyamide resins having an average carbon atom number of more than 6 per amide group include copolymers using several kinds of raw material monomers that form aliphatic homopolyamide resins having an average carbon atom number of more than 6 per amide group, as well as caprolactam / hexamethylenediaminoazelaic acid copolymer (polyamide 6 / 69), caprolactam / hexamethylenediaminosebacic acid copolymer (polyamide 6 / 610), caprolactam / hexamethylenediaminoundecanedicarboxylic acid copolymer (polyamide 6 / 611), caprolactam / hexamethylenediaminododecanedicarboxylic acid copolymer ( Examples of the copolymer include polyamide 6 / 612), caprolactam / aminoundecanoic acid copolymer (polyamide 6 / 11), caprolactam / lauryllactam copolymer (polyamide 6 / 12), caprolactam / hexamethylenediaminoadipic acid / lauryllactam copolymer (polyamide 6 / 66 / 12), caprolactam / hexamethylenediaminoadipic acid / hexamethylenediaminosebacic acid copolymer (polyamide 6 / 66 / 610), and caprolactam / hexamethylenediaminoadipic acid / hexamethylenediaminododecanedicarboxylic acid copolymer (polyamide 6 / 66 / 612). These aliphatic polyamide resins (B) may be used singly or in combination of two or more.

[0059] Among these, from the viewpoint of flexibility, the aliphatic polyamide resin (B) is preferably one having an average number of carbon atoms per amide group of 8 to 12, more preferably 10 to 12. It is particularly preferably at least one selected from the group consisting of polyamide 11, polyamide 12, polyamide 612, polyamide 611, polyamide 610, polyamide 6 / 12 copolymer, and polyamide 6 / 6 / 12 copolymer.

[0060] The degree of polymerization of the aliphatic polyamide resin (B) is not particularly limited, but the relative viscosity measured at 25°C in a solution of 1 g of polyamide resin in 100 ml of 96% concentrated sulfuric acid according to JIS K 6933 is preferably 1.10 to 5.00, more preferably 1.50 to 4.50, and particularly preferably 1.50 to 3.00.

[0061] In 100% by mass of the polyamide resin composition, the content of the aliphatic polyamide resin (B) having an average number of carbon atoms per amide group of more than 6 is 40 to 79% by mass, preferably 45 to 77% by mass, more preferably 50 to 75% by mass. When the content of the aliphatic polyamide resin (B) is within the above range, a molded product having both flexibility and toughness and excellent impact resistance can be obtained.

[0062] <Aromatic polyamide resin (C)> The polyamide resin composition contains an aromatic polyamide resin (C). When the polyamide resin composition contains the aromatic polyamide resin (C), the toughness and impact resistance can be improved due to the rigid structure thereof. The aromatic polyamide resin is an aromatic polyamide resin containing at least one aromatic monomer component, and is obtained by polycondensation of, for example, an aliphatic dicarboxylic acid and an aromatic diamine, an aromatic dicarboxylic acid and an aliphatic diamine, or an aromatic diamine and an aromatic dicarboxylic acid as raw materials.

[0063] Examples of the aliphatic diamine and aliphatic dicarboxylic acid as raw materials include the same as those exemplified in the description of the aliphatic copolyamide resin. Examples of aromatic diamines include metaxylylenediamine and paraxylylenediamine, and examples of aromatic dicarboxylic acids include naphthalenedicarboxylic acid, terephthalic acid, isophthalic acid, and phthalic acid. These aromatic diamines and aromatic dicarboxylic acids may be used alone or in appropriate combination of two or more.

[0064] Specific examples include polynonamethylene terephthalamide (polyamide 9T), polyhexamethylene terephthalamide (polyamide 6T), polyhexamethylene isophthalamide (polyamide 6I), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (polyamide 66 / 6T), polyhexamethylene terephthalamide / polycaproamide copolymer (polyamide 6T / 6), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (polyamide 66 / 6I), Polyhexamethylene isophthalamide / polycaproamide copolymer (polyamide 6I / 6), polydodecaamide / polyhexamethylene terephthalamide copolymer (polyamide 12 / 6T), polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (polyamide 66 / 6T / 6I), polyhexamethylene adipamide / polycaproamide / polyhexamethylene isophthalamide copolymer (polyamide 66 / 6 / 6I), polyhexamethylene terephthalamide / Examples of the aromatic polyamide (C) include polyhexamethylene isophthalamide copolymer (polyamide 6T / 6I), polyhexamethylene terephthalamide / poly(2-methylpentamethylene terephthalamide) copolymer (polyamide 6T / M5T), polyxylylene adipamide (polyamide MXD6), etc. These aromatic polyamides (C) may be used singly or in combination of two or more.

[0065] Among these, from the viewpoint of impact resistance, aromatic copolymerized polyamides containing at least two monomer components are preferred, semi-aromatic polyamides in which one or more aromatic monomer components are copolymerized with one or more aliphatic monomer components are more preferred, and polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (polyamide 6T / 6I) and polyxylylene adipamide (polyamide MXD6) are even more preferred.

[0066] A particularly useful example of the aromatic polyamide resin (C) is an amorphous partially aromatic copolymer polyamide resin containing at least two aromatic monomer components. The amorphous partially aromatic copolymer polyamide resin is preferably an amorphous polyamide having a glass transition temperature of 100°C or higher, determined from the peak temperature of the loss modulus in an oven-dry state obtained by measuring dynamic viscoelasticity. An example of the amorphous partially aromatic copolymer polyamide resin is polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (polyamide 6T / 6I). Here, "amorphous" means that the heat of crystalline fusion measured by a differential scanning calorimeter (DSC) is 1 cal / g or less.

[0067] The degree of polymerization of the aromatic polyamide resin (C) is not particularly limited, but the relative viscosity measured at 25°C in accordance with JIS K 6933 by dissolving 1 g of the polyamide resin in 100 ml of special-grade m-cresol is preferably 1.50 to 4.00, more preferably 1.80 to 2.50.

[0068] In 100% by mass of the polyamide resin composition, the content of the aromatic polyamide resin (C) is 0.1 to 35% by mass, preferably 0.1 to 33% by mass, and more preferably 0.2 to 30% by mass. When the content of the aromatic polyamide resin (C) is within the above range, flexibility is not impaired and impact resistance is excellent.

[0069] <Aliphatic polyamide resin (D) having an average of 6 or less carbon atoms per amide group> The polyamide resin composition preferably optionally contains an aliphatic polyamide resin (D) having an average number of carbon atoms per amide group of 6 or less (hereinafter also referred to as "aliphatic polyamide resin (D)"). If the polyamide resin composition contains an aliphatic polyamide resin (D) having an average of 6 or less carbon atoms per amide group, the blending of the aromatic polyamide (C) can be facilitated, which is preferable from the viewpoint of molding processability.

[0070] Examples of the aliphatic polyamide resin (D) having an average carbon atom number per amide group of 6 or less include polycaprolactam (polyamide 6), polyethylene adipamide (polyamide 26), polytetramethylene succinamide (polyamide 44), polytetramethylene glutamide (polyamide 45), polytetramethylene adipamide (polyamide 46), polytetramethylene suberamide (polyamide 48), polypentamethylene succinamide (polyamide 54), polypentamethylene glutamide (polyamide 55), polypentamethylene adipamide (polyamide 56), polyhexamethylene adipamide (polyamide 66), and caprolactam / hexamethylenediaminoadipic acid copolymer (polyamide 6 / 66). These aliphatic polyamide resins (D) may be used singly or in combination of two or more. Among these, polyamide 6 is preferred from the viewpoint of compatibility with the aromatic polyamide resin (C).

[0071] The degree of polymerization of the aliphatic polyamide resin (D) is not particularly limited, but the relative viscosity measured at 25°C in a solution of 1 g of polyamide resin in 100 ml of 96% concentrated sulfuric acid according to JIS K 6933 is preferably 1.10 to 5.00, more preferably 1.50 to 4.20.

[0072] The content of the aliphatic polyamide resin (D) having an average number of carbon atoms per amide group of 6 or less is 0 to 10% by mass in 100% by mass of the polyamide resin composition. When the content of the aliphatic polyamide resin (D) is within the above range, flexibility is good and blending of the aromatic polyamide resin (C) becomes easy.

[0073] (Production of polyamide resin) Examples of polyamide resin production equipment include known polyamide production equipment such as batch-type reaction vessels, single- or multi-vessel continuous reaction vessels, tubular continuous reaction vessels, and kneading reaction extruders such as single-screw kneading extruders and twin-screw kneading extruders. Known polymerization methods, such as melt polymerization, solution polymerization, and solid-state polymerization, can be used, and polymerization can be carried out by repeating operations under normal pressure, reduced pressure, and increased pressure. These polymerization methods can be used alone or in appropriate combination.

[0074] The terminal amino group concentration of the polyamide resin, as determined by dissolving the polyamide resin in a mixed solvent of phenol and methanol and subjecting it to neutralization titration, is preferably 30 μmol / g or more, more preferably 30 μmol / g or more and 110 μmol / g or less, and even more preferably 30 μmol / g or more and 70 μmol / g or less. Within this range, the polyamide resin composition has good moldability.

[0075] When a polyamide resin contains two or more polyamide resins with different terminal amino group concentrations, the terminal amino group concentration in the polyamide resin is preferably measured by the neutralization titration method described above. However, when the terminal amino group concentration of each polyamide resin and its mixing ratio are known, the terminal amino group concentration of the polyamide resin may be determined by adding up the values ​​obtained by multiplying each terminal amino group concentration by the mixing ratio.

[0076] <Other resins> The polyamide resin composition may contain a thermoplastic resin other than a polyamide elastomer and a polyamide resin, provided that the object of the present invention is not impaired. The content of the thermoplastic resin other than a polyamide elastomer and a polyamide resin is preferably 2% by mass or less, more preferably 0 to 1.5% by mass, based on 100% by mass of the polyamide resin composition.

[0077] <Other ingredients> The polyamide resin composition may contain, as appropriate, functionality-imparting agents such as dyes, pigments, fibrous reinforcements, particulate reinforcements, plasticizers, antioxidants, heat resistance agents, foaming agents, weather resistance agents, crystal nucleating agents, crystallization accelerators, mold release agents, lubricants, antistatic agents, flame retardants, flame retardant assistants, and colorants, in addition to the above components, provided that the object of the present invention is not impaired. The content of the optional component is preferably 0.01 to 1 mass %, more preferably 0.05 to 0.5 mass %, based on 100 mass % of the polyamide resin composition.

[0078] [Method of producing polyamide resin composition] The method for producing the polyamide resin composition is not particularly limited, and the following method can be applied, for example. The raw materials of each component are mixed using a commonly known melt kneader such as a single-screw extruder, a twin-screw extruder, a Banbury mixer, a kneader, a mixing roll, etc. A method of simply mixing the raw materials of each component using a commonly known mixer such as a tumbler mixer or a blender can also be applied.

[0079] For example, when a twin-screw extruder is used, any of the following methods may be used: a method in which all of the raw materials are blended and then melt-kneaded; a method in which some of the raw materials are blended and then melt-kneaded, and then the remaining raw materials are blended and melt-kneaded; or a method in which some of the raw materials are blended and then the remaining raw materials are mixed using a side feeder while melt-kneading; however, the method in which all of the raw materials are blended and then melt-kneaded is preferred.

[0080] (MFR of polyamide resin composition) The polyamide resin composition preferably has a melt flow rate (MFR) of less than 15 g / 10 min, more preferably 4 g / 10 min or more but less than 15 g / 10 min, and even more preferably 7 g / 10 min or more but less than 15 g / 10 min, as measured at 190°C under a load of 1.00 kg in accordance with ISO 1133. When the MFR is within this range, the polyamide resin has good moldability without impairing the toughness of the resulting molded article.

[0081] (Density of Polyamide Resin Composition) The density of the polyamide resin composition is 1.02 g / cm 3 More than 1.03 to 1.10 g / cm is preferable. 3 More preferably, 1.03 to 1.06 g / cm 3 is more preferable. When the density is within this range, various inorganic additives such as magnetic powder tend to be more uniformly dispersed. The density of the polyamide resin composition is calculated by multiplying the density of each component by its content (mass%) and then calculating the sum of the results. The density of each component was measured in accordance with ISO 1183-3.

[0082] The polyamide resin composition is thought to be able to maintain flexibility over a wide temperature range because the aliphatic polyamide resin (B), the polyamide elastomer (A), and the aromatic polyamide resin (C) each absorb energy at different temperature ranges, and is expected to be able to suppress cracking caused by stress concentration due to dimensional changes.

[0083] [Polyamide resin composition molded articles and their uses] The polyamide resin composition can be suitably used for producing injection-molded articles by injection molding, extrusion-molded articles by extrusion molding, blow-molded articles by blow molding, and rotational molded articles by rotational molding. The polyamide resin composition has good injection moldability, so it can be suitably used for producing injection-molded articles by injection molding.

[0084] The method for producing an injection-molded article from the polyamide resin composition by injection molding is not particularly limited, and any known method can be used.

[0085] The method for producing an extrusion molded article from the polyamide resin composition by extrusion molding is not particularly limited, and known methods can be used.

[0086] The method for producing a blow-molded article from a polyamide resin composition by blow molding is not particularly limited, and known methods can be used.

[0087] The method for producing a rotational molded article from the polyamide resin composition by rotational molding is not particularly limited, and any known method can be used. For example, the method described in WO 2019 / 054109 can be referenced.

[0088] Suitable applications for injection molded products by injection molding, extrusion molded products by extrusion molding, blow molded products by blow molding, and rotational molded products by rotational molding include, but are not limited to, automotive parts such as spoilers, air intake ducts, intake manifolds, resonators, fuel tanks, gas tanks, hydraulic oil tanks, fuel filler tubes, fuel delivery pipes, and various other hoses, tubes, and tanks; machine parts such as power tool housings and pipes; electric and electronic parts such as tanks, tubes, hoses, and films; household and office supplies; building material-related parts; and furniture parts.

[0089] Furthermore, since the polyamide resin composition has excellent gas barrier properties, it is suitable for use in molded articles that come into contact with high-pressure gas, such as tanks, tubes, hoses, films, etc. The type of gas is not particularly limited and examples include hydrogen, nitrogen, oxygen, helium, methane, butane, propane, etc., with gases having low polarity being preferred, and hydrogen, nitrogen, and methane being particularly preferred.

[0090] [Magnetic material-resin composite material containing polyamide resin composition and magnetic powder] The polyamide resin composition can be used as a magnetic material-resin composite material by blending it with magnetic powder. The magnetic powder is not particularly limited as long as it is a known magnetic powder that can be used in plastic magnets and has the function of imparting magnetism. Examples include ferrite magnetic powder, alnico magnetic powder, and rare earth magnetic powder. Ferrite magnetic powders include barium ferrite magnetic powders such as iron oxide and barium carbonate, and strontium ferrite magnetic powders such as iron oxide and strontium carbonate. Alnico magnetic powders include alnico powders made of nickel, aluminum, cobalt, and copper, and alnico powders made of nickel, aluminum, cobalt, copper, and titanium. Rare earth magnetic powders include samarium-cobalt magnets, rare earth cobalt magnets in which the cobalt component of samarium-cobalt is replaced with copper, iron, titanium, zirconium, hafnium, niobium, tantalum, etc., and neodymium-iron-boron magnets. These may be used alone or in combination.

[0091] The average particle size of the magnetic powder is preferably 0.1 to 300 μm, more preferably 0.1 to 200 μm, and even more preferably 0.5 to 100 μm. If the average particle size of the magnetic powder exceeds the above range, the flowability of the magnetic material-resin composite material and the mechanical strength of the molded product may decrease. The blending amount of the magnetic powder is preferably 50 to 98 mass % of the entire magnetic material-resin composite material, more preferably 65 to 97 mass %, and even more preferably 70 to 95 mass %.

[0092] If the blending amount is less than the above-mentioned value, the residual magnetic flux density will be low, making it less practical for use in permanent magnets, and the effect on the flow properties of the resin may be small. On the other hand, if the blending amount exceeds the above-mentioned value, the magnetic field orientation will be poor, the improvement in residual magnetic flux density that accompanies the reduction in resin component will not be observed, and the flowability will be poor because of the small amount of resin, which may cause problems such as poor filling during the kneading and molding processes, making it less practical.

[0093] The magnetic powder may be pretreated with a coupling agent or surface modifier to improve dispersibility or adhesion when blended into a polyamide resin composition. Conventional coupling agents or surface modifiers, such as silane-based, titanate-based, aluminum-based, phosphite ester or other organic phosphorus compound-based, chromium-based, and methacrylate-based, can be used as the coupling agent or surface modifier. The optimum type of these agents is selected depending on the type of resin used as the binder. Among these, amino group-containing silane-based compounds and titanate-based compounds are more preferred to enhance compatibility with polyamide resins. In addition, additives such as lubricants and stabilizers can be used to improve the flowability, moldability, and magnetic properties of the magnetic material-resin composite material.

[0094] The magnetic material-resin composite material may contain, in addition to the above components, appropriate functionality-imparting agents such as dyes, pigments, fibrous reinforcements, particulate reinforcements, plasticizers, antioxidants, heat resistance agents, foaming agents, weather resistance agents, crystal nucleating agents, crystallization accelerators, mold release agents, lubricants, stabilizers, antistatic agents, flame retardants, flame retardant assistants, and colorants, provided that the object of the present invention is not impaired.

[0095] (Method of manufacturing magnetic resin composite material) The magnetic material-resin composite material is produced by mixing a polyamide resin composition and a magnetic powder in a mixing step and then kneading the mixture, or by directly mixing each component of the polyamide resin composition with the magnetic powder in a direct mixing step and then kneading the mixture. In the mixing step, the magnetic powder, the polyamide resin composition or each component of the polyamide resin composition, and various additives, if necessary, are blended and mixed by a known method. The mixing step is preferably performed before the kneading step described below. The use of a solvent during mixing is an effective means for uniformly adding the coupling agent and lubricant when used, but is not necessarily required. The mixer is not particularly limited, and examples include ribbon mixers, V-type mixers, rotary mixers, Henschel mixers, flash mixers, Nauta mixers, and tumblers. It is also effective to add, grind, and mix the materials using a rotary ball mill, vibration ball mill, planetary ball mill, wet mill, jet mill, hammer mill, cutter mill, etc.

[0096] In this case, the polyamide resin composition for molding a magnetic material-resin composite may be in any form such as pellets, beads, powder, paste, etc., but a fine particle size form is preferred in order to improve the homogeneity of the mixture.

[0097] The kneading process involves kneading the mixed magnetic powder, polyamide resin composition, and optional additives, or the mixed magnetic powder, each component of the polyamide resin composition, and optional additives, at a temperature range of 50 to 400°C using a batch kneader such as a Brabender, a Banbury mixer, a Henschel mixer, a helical rotor, a roll, a single-screw extruder, or a twin-screw extruder. The kneading temperature is generally selected within a temperature range in which the polyamide resin melts but does not decompose. The kneaded material is extruded into strands or sheets and then cut, or hot-cut, underwater-cut, or cooled and solidified into blocks, which are then crushed into pellets or powder for molding. This allows the magnetic material-resin composite material to be obtained.

[0098] (Molded products made from magnetic resin composite materials and their applications) In order to obtain a molded product of the magnetic material-resin composite material from the magnetic material-resin composite material obtained in the kneading step, a molding step is carried out, in which a molding process is further carried out. This can be done either by a one-stage molding method, in which the mixture is melt-kneaded and molded into the desired shape as it is, or by a two-stage molding method, in which after the kneading step, a molding step is carried out by a conventional method such as injection molding, extrusion molding, or compression molding while applying a magnetic field. Among these, methods for producing molded articles of magnetic material-resin composite materials with high magnetic properties include injection molding, extrusion molding, and compression molding, in which pelletized or powdered magnetic material-resin composite materials are heated and melted, and then kneaded as necessary. In the case of extrusion molding, this can also be performed in conjunction with kneading. Among these molding methods, injection molding is particularly useful because it can produce magnetic material-resin composites with excellent surface smoothness and magnetic properties. For details on injection molding and extrusion molding, please refer to the contents described in the section on polyamide resin compositions. The molding temperature is the same as the kneading temperature.

[0099] The molded product is usually further magnetized to improve its performance as a permanent magnet. Magnetization is performed by a conventional method, such as using an electromagnet that generates a static magnetic field or a capacitor magnetizer that generates a pulsed magnetic field. The magnetic field strength is preferably 15 kOe or more, and more preferably 30 kOe or more.

[0100] Molded products made from magnetic resin composite materials are used in electromagnetic equipment, in-vehicle electromagnetic equipment (electric motors, generators, etc.), toys, office equipment, audio equipment, etc. [Example]

[0101] 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.

[0102] The measured values ​​in the examples were measured by the following measurement methods. <density> The density of each component was multiplied by the content (mass%) and the sum was calculated. The density of each component was measured in accordance with ISO1183-3.

[0103] <mfr> The MFR (melt flow rate) of the polyamide resin composition was measured in accordance with ISO 1133 at 190°C under a load of 1.00 kg. From the obtained MFR measurement results, the moldability was evaluated according to the following criteria. ◎: MFR is 7g / 10min or more and less than 15g / 10min. 〇: MFR is 4g / 10min or more to less than 7g / 10min. ×: MFR is less than 4 g / 10 min or 15 g / 10 min or more.

[0104] <Evaluation of mechanical properties> If all of the following evaluations of the mechanical properties 1 to 3 are either ◯ or ⊚, it can be expected that cracks in the molded product will be suppressed.

[0105] 1. Resilience <Tensile yield stress, tensile yield strain, nominal tensile strain at break, and tensile modulus> In accordance with ISO527-2 / 1A / 50, the tensile yield stress and tensile yield strain of the test specimens (test specimen size: 10 × 170 × 4 mm) were measured at 23°C, relative humidity of 50% RH, and a test speed of 50 mm / min using an automatic extensometer AGX-AT / SIE-560SA manufactured by Shimadzu Corporation. From the measurement results of the tensile yield stress, the toughness was evaluated according to the following criteria. ◎: Tensile yield stress is 35 MPa or more. Good: Tensile yield stress is 32 MPa or more and less than 35 MPa. ×: Tensile yield stress is less than 32 MPa. From the measurement results of the tensile yield strain obtained, the toughness was evaluated according to the following criteria. ◎: Tensile yield strain is 9% or more. Good: Tensile yield strain is 7% or more and less than 9%. ×: Tensile yield strain is less than 7%. From the measurement results of the nominal tensile fracture strain obtained, the toughness was evaluated according to the following criteria. ◎: Nominal tensile breaking strain is 20% or more. Good: Nominal tensile fracture strain is 14% or more and less than 20%. ×: Nominal tensile strain at break is less than 14%. From the measurement results of the tensile modulus, the toughness was evaluated according to the following criteria. ◎: Tensile modulus of elasticity is 1100 MPa or more. ◯: Tensile modulus of elasticity is 1000 MPa or more but less than 1100 MPa. ×: Tensile modulus of elasticity less than 1000 MPa.

[0106] 2.Flexibility <Flexural strength and flexural modulus> In accordance with ISO178, the maximum bending strength and bending modulus of the test specimen (test specimen size: 10 × 80 × 4 mm) were measured in three-point bending mode using a Shimadzu fully automatic bending tester AGX-AT / SIE-560SA at 23°C, a relative humidity of 50% RH, and a test speed of 2 mm / min. From the bending strength measurement results obtained, flexibility was evaluated according to the following criteria. ◎: Bending strength is 45 MPa or more. Good: Bending strength is 39 MPa or more and less than 45 MPa. ×: Bending strength is less than 39 MPa. From the measurement results of the flexural modulus, the flexibility was evaluated according to the following criteria. ◎: Flexural modulus is 1100 MPa or more. Good: Flexural modulus is 1000 MPa or more and less than 1100 MPa. ×: Flexural modulus less than 1000 MPa.

[0107] 3. Shock resistance <Charpy impact strength> In accordance with ISO179-1 / 1eA, edgewise impact tests were conducted (n=10) using a Yasuda Seiki universal impact tester No. 141-PC at 23°C and -40°C using 4mm thick test pieces (10 x 80 x 4mm) with an A notch. In Table 1, "C" indicates complete failure. From the measurement results of the Charpy impact strength at 23°C, the impact resistance was evaluated according to the following criteria. ◎: Charpy impact strength is 5kJ / m 2 That's all. 〇: Charpy impact strength is 4kJ / m 2 More than 5kJ / m 2 less than. ×: Charpy impact strength is 4kJ / m 2 less than. From the measurement results of the Charpy impact strength at -40°C, the impact resistance was evaluated according to the following criteria. ◎: Charpy impact strength is 3kJ / m 2 That's all. 〇: Charpy impact strength is 2kJ / m 2 More than 3kJ / m 2 less than. ×: Charpy impact strength is 2 kJ / m 2 less than.

[0108] [Production Example 1: Production of polyamide elastomer] A 70-liter pressure vessel equipped with a stirrer, thermometer, torque meter, pressure gauge, nitrogen gas inlet, pressure regulator, and polymer outlet was charged with 8.00 kg of 12-aminododecanoic acid (Ube Industries, Ltd.), 1.49 kg of adipic acid (Asahi Kasei Chemicals Corporation), 10.51 kg of an XYX triblock polyether diamine (Huntsman, trade name: ELASTAMINE RT-1000) represented by the above formula (3) (x = 3, y = 9, z = 2), 0.06 kg of a hindered phenol antioxidant (BASF Japan, trade name: Irganox® 245), and 0.03 kg of sodium hypophosphite (Taihei Chemical Industry Co., Ltd.). After thoroughly replacing the atmosphere with nitrogen, the vessel was heated from room temperature to 230 °C over 1 hour to conduct polymerization.

[0109] [Examples 1 to 11, Comparative Examples 1 to 6] The components listed in Table 1 were blended in a blender for 10 minutes to obtain each blend composition. Test specimens to be used for evaluating the mechanical properties were prepared from each of the obtained blend compositions using a Sumitomo SG75 injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. Test specimens for Examples 1 and 4 to 11 were prepared by setting the cylinder temperature of the injection molding machine to 250°C, and test specimens for Examples 2 and 3 were prepared by setting the cylinder temperature to 270°C. For Comparative Example 1, the cylinder temperature was set to 210°C, and for Comparative Examples 2 to 6, the cylinder temperature was set to 250°C. The results of the physical properties and mechanical property evaluations are shown in Table 1. The units of compositions in the tables are mass %, and the entire polyamide resin composition is taken as 100 mass %.

[0110] [Table 1]

[0111] The materials used in the examples and comparative examples are as follows. Polyamide elastomer (A) Polyamide elastomer produced in Production Example 1 (relative viscosity: 1.83) Aliphatic polyamide resin (B) Polyamide 12 (PA12): Ube Industries, Ltd. (relative viscosity: 1.60) Polyamide 6 / 12 (PA6 / 12 = 25 / 75 mass ratio): manufactured by Ube Industries, Ltd. (relative viscosity: 1.72) Aliphatic polyamide resin (D) Polyamide 6 (PA6): Ube Industries, Ltd. (relative viscosity: 2.47) The relative viscosity of the polyamide resins (B) and (D) is a value measured at 25°C by dissolving 1 g of polyamide resin in 100 ml of 96% concentrated sulfuric acid according to JIS K 6933. The relative viscosity of the polyamide elastomer (A) is a value measured at 25°C by dissolving 0.25 g of polyamide elastomer in 50 ml of special-grade m-cresol according to JIS K 6920-2. Aromatic polyamide resin (C) Polyamide 6T / 6I (PA6T / 6I): EMS-CHEMIE (Japan) Co., Ltd., product name "Grivory (registered trademark) G21"

[0112] It can be seen from Table 1 that the polyamide resin compositions of Examples 1 to 11 all have moldability, toughness, flexibility and impact resistance. Comparative Example 1 does not contain the polyamide elastomer (A) or the aromatic polyamide (C), and therefore has high tensile yield stress, nominal tensile strain at break, and tensile modulus, but has low tensile yield strain and Charpy impact strength at 23°C, making it prone to breakage and lacking in toughness. It also has poor moldability. In Comparative Example 2, the amount of polyamide elastomer (A) is less than the range of the present invention, so the nominal tensile break strain and Charpy impact strength values ​​are poor, and it is clear that impact resistance is lacking. In Comparative Example 3, the amount of aliphatic polyamide resin (B) is less than the range of the present invention, so the tensile yield stress is low and the toughness is lacking. In Comparative Example 4, the amount of polyamide elastomer (A) is greater than the range of the present invention, and therefore the tensile yield stress, tensile modulus, flexural strength and flexural modulus are low, and the toughness and flexibility are poor. In Comparative Example 5, the amount of aliphatic polyamide resin (B) was greater than the range of the present invention, and therefore the Charpy impact strength value at 23° C. was poor, indicating a lack of impact resistance. In Comparative Example 6, the amount of polyamide elastomer (A) was less than the range of the present invention, and the amount of aromatic polyamide (C) was greater, so the values ​​of MFR, tensile yield strain, nominal tensile break strain, and Charpy impact strength were poor, and it was found that the moldability, toughness, and impact resistance were lacking.< / mfr>

Claims

1. The polyamide resin composition comprises, based on 100% by mass of the polyamide resin composition, 15 to 35% by mass of a polyamide elastomer (A), 45 to 77% by mass of an aliphatic polyamide resin (B) having an average number of carbon atoms per amide group of more than 6, 0.1 to 35% by mass of an aromatic polyamide resin (C), and 0 to 10% by mass of an aliphatic polyamide resin (D) having an average number of carbon atoms per amide group of 6 or less.

2. 2. The polyamide resin composition according to claim 1, wherein the polyamide elastomer (A) has a polyether structure.

3. Density: 1.02 g / cm ３ The polyamide resin composition according to claim 1 or 2, wherein the polyamide resin composition is a polyamide resin composition comprising the above-mentioned components.

4. ISO 4. The polyamide resin composition according to claim 1, wherein the MFR measured in accordance with JIS No. 1133 at 190° C. under a load of 1.00 kg is less than 15 g / 10 min.

5. The polyamide resin composition according to any one of claims 1 to 4, wherein the polyamide elastomer (A) is a polymer containing a structural unit derived from an aminocarboxylic acid compound represented by the following formula (1) and / or a lactam compound represented by the following formula (2), a structural unit derived from an XYX triblock polyether diamine compound represented by the following formula (3), and a structural unit derived from a dicarboxylic acid compound represented by the following formula (4): 【Chemistry 1】 [However, R １ represents a linking group containing a hydrocarbon chain. 【Chemistry 2】 [However, R ２ represents a linking group containing a hydrocarbon chain. 【Transformation 3】 [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.] 【Chemistry 4】 [However, R ３ represents a linking group containing a hydrocarbon chain, and m is 0 or 1.

6. A molded article made from the polyamide resin composition according to any one of claims 1 to 5.

7. A magnetic material-resin composite material comprising the polyamide resin composition according to any one of claims 1 to 5 and magnetic powder.

8. A molded product made from the magnetic material-resin composite material of claim 7.

Images