Polyamide resin composition, method for producing polyamide resin composition and molding

Abstract

To provide a polyamide resin composition which can enhance reflow heat resistance of a molding, a method for producing a polyamide resin composition using the polyamide resin composition and a molding of the same.SOLUTION: A polyamide resin composition contains a polyamide resin (A) having a melting point measured by a differential scanning calorimeter (DSC) of 280°C or higher, a halogen-based flame retardant (B), and a polyolefin-based copolymer (C), wherein the polyolefin-based copolymer (C) includes a structural unit derived from ethylene or an α-olefin-based monomer having 3 to 8 carbon atoms, and a structural unit including a glycidyl group, and when a content of the polyamide resin (A) is 100 mass%, a content of the polyolefin-based copolymer (C) is 0.2 mass% to 3.5 mass%.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a polyamide resin composition, a method for producing the polyamide resin composition, and a molded article. [Background technology]

[0002] Polyamide resin compositions have been known as molding materials. Polyamide resin compositions are widely used as materials for various parts, such as automotive parts and electric / electronic parts, and are known to have excellent mechanical strength in molded articles. In particular, polyamide resin compositions containing polyamide resins with high melting points are known to have excellent heat resistance and are therefore suitable for use at high temperatures.

[0003] For example, Patent Document 1 discloses a resin composition comprising a polyarylene sulfide resin (A), an aromatic polyamide resin (B) containing terephthalic acid amide as an essential repeating unit, an elastomer (C) having a reactive group, and a silane coupling agent (D). Patent Document 1 states that a film having a low dielectric constant, no deformation or shrinkage at high temperatures, and high toughness has been produced. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2020 / 170919 Summary of the Invention [Problem to be solved by the invention]

[0005] When a molded article of a polyamide resin composition containing a polyamide resin having a high melting point is used for automotive parts, electrical and electronic parts, etc., the molded article may be reflow soldered to a substrate. During this process, heating in the reflow process (reflow treatment) evaporates the moisture contained in the molded article, and the resulting vapor pressure can cause blisters (expansion) in the molded article. From the perspective of improving the appearance and dimensional accuracy of molded articles, there has been a demand for polyamide resin compositions that are less likely to cause blisters when heated (high reflow heat resistance). Furthermore, molded articles of polyamide resin compositions may require high flame retardancy when used for, for example, automotive parts and electrical and electronic parts.

[0006] It is known that a flame retardant is added to a polyamide resin composition to enhance the flame retardancy of the polyamide resin composition. However, according to the investigations of the present inventors, there was a problem that when a halogen-based flame retardant such as brominated polystyrene is combined with the resin composition described in Patent Document 1, the reflow heat resistance of the molded product becomes insufficient.

[0007] An object of the present invention is to provide a polyamide resin composition capable of improving the reflow heat resistance of a molded article, a method for producing a polyamide resin composition using the polyamide resin composition, and a molded article made from the polyamide resin composition. [Means for solving the problem]

[0008] In order to solve the above problems, one aspect of the present invention relates to the following polyamide resin compositions [1] to [7].

[0009] [1] A polyamide resin (A) having a melting point of 280°C or higher as measured by a differential scanning calorimeter (DSC), a halogen-based flame retardant (B); a polyolefin copolymer (C); Including, The polyolefin copolymer (C) contains a structural unit derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms and a structural unit containing a glycidyl group, The content of the polyolefin copolymer (C) is 0.2% by mass to 3.5% by mass when the content of the polyamide resin (A) is taken as 100% by mass. Polyamide resin composition.

[0010] [2] The mass of the structural unit containing the glycidyl group is 5% by mass or more relative to 100% by mass of all structural units constituting the polyolefin copolymer (C). [1] The polyamide resin composition according to [1].

[0011] [3] The polyolefin copolymer (C) contains a structural unit derived from ethylene and a structural unit derived from glycidyl (meth)acrylate. [1] or [2]. The polyamide resin composition.

[0012] [4] The polyolefin copolymer (C) is substantially free of structural units other than the structural units derived from ethylene or the structural units derived from glycidyl (meth)acrylate. [3] The polyamide resin composition according to [3].

[0013] [5] The melting point of the polyolefin copolymer (C) measured by a differential scanning calorimeter (DSC) is 100°C or higher. The polyamide resin composition according to any one of [1] to [4].

[0014] [6] The content of the polyolefin copolymer (C) is 0.10% by mass to 1.50% by mass, when the total mass of the polyamide resin composition is 100% by mass. The polyamide resin composition according to any one of [1] to [5].

[0015] [7] The molar amount of the structural unit having a glycidyl group in the polyolefin copolymer (C) contained in the polyamide resin composition is expressed as a molecule, the ratio of the amount of terminal carboxy groups in the polyamide resin (A) to the amount of terminal amino groups in the polyamide resin (A) contained in the polyamide resin composition, when the total molar amount is taken as the denominator, is 1.0 / 1.0 to 10.0 / 1.0; The polyamide resin composition according to any one of [1] to [6].

[0016] In order to solve the above problems, one aspect of the present invention relates to the following method for producing a polyamide resin composition [8].

[0017] [8] A polyamide resin (A) having a melting point of 280°C or higher as measured by a differential scanning calorimeter (DSC), a halogen-based flame retardant (B); a polyolefin copolymer (C); A method for producing a polyamide resin composition, comprising a step of melt-kneading the The polyolefin copolymer (C) contains a structural unit derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms and a structural unit containing a glycidyl group, The content of the polyolefin copolymer (C) is 0.2% by mass to 3.5% by mass when the content of the polyamide resin (A) is taken as 100% by mass. A method for producing a polyamide resin composition.

[0018] In order to solve the above problems, one aspect of the present invention relates to the following molded article [9].

[0019] [9] A product obtained by molding the polyamide resin composition according to any one of [1] to [7]. Molded body. [Effects of the Invention]

[0020] According to the present invention, it is possible to provide a polyamide resin composition capable of improving the reflow heat resistance of a molded article, a method for producing a polyamide resin composition using the polyamide resin composition, and a molded article thereof. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a diagram showing the relationship between the temperature and time of the reflow process in the reflow heat resistance test carried out in the examples of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments.

[0023] In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits.

[0024] 1. Polyamide resin composition The polyamide resin composition according to the present embodiment comprises a polyamide resin (A) having a melting point of 280°C or higher as measured by differential scanning calorimetry (DSC), a halogen-based flame retardant (B), and a polyolefin copolymer (C), wherein the polyolefin copolymer (C) comprises a structural unit derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms and a structural unit containing a glycidyl group, and the content of the polyolefin copolymer (C) is 0.2 to 3.5% by mass when the content of the polyamide resin (A) is taken as 100% by mass.

[0025] The blisters that form in the molded body during the reflow process described above occur when the moisture contained in the molded body passes through the interior of the molded body and attempts to evaporate from the surface of the molded body, causing the molded body to deform from the inside due to the water vapor pressure that arises inside the molded body.

[0026] In particular, when a halogenated flame retardant (B) is contained, the halogenated flame retardant (B) often has low affinity with the polyamide resin (A), which tends to reduce the strength (interfacial strength) at the interface between the polyamide resin (A) and the halogenated flame retardant (B). As a result, when the moisture contained inside evaporates from the surface of the molded body, the interface cannot withstand the vapor pressure generated inside the molded body, and the interface is prone to separation, which tends to lead to deformation from within the molded body.

[0027] Furthermore, for example, brominated polystyrene and polybrominated styrene, which are widely used as halogen-based flame retardants (B), have a lower melting point than the polyamide resin (A). Therefore, the melting point of a molded article containing the halogen-based flame retardant (B) is likely to decrease, and accordingly, the melt tension and high-temperature strength of the molded article are likely to decrease. As a result, the molded article is likely to deform due to the water vapor pressure generated inside the molded article.

[0028] Therefore, when the polyamide resin composition contains a halogen-based flame retardant (B), the molded body is likely to deform due to the water vapor pressure generated inside the molded body, and blisters are likely to occur significantly during reflow treatment (reflow heat resistance is likely to decrease).

[0029] The reason why the use of the polyamide resin composition suppresses deformation of the molded body due to water vapor pressure generated inside the molded body and improves reflow heat resistance is not entirely clear, but is thought to be as follows.

[0030] The terminal carboxyl groups, terminal amino groups, and amide groups in the molecular chain of the polyamide resin (A) react with the glycidyl groups of the polyolefin copolymer (C), increasing the molecular weight of the polyamide resin (A), which facilitates improving the melt tension and high-temperature strength of the molded article. This makes the molded article less susceptible to deformation due to water vapor pressure, and facilitates improving reflow heat resistance.

[0031] Furthermore, although the polyolefin copolymer (C) generally has a lower melting point than the polyamide resin (A), the presence of structural units derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms makes it easier to increase the melting point of the polyolefin copolymer (C). This makes it possible to suppress a decrease in the melting point of a molded article containing the polyolefin copolymer (C), and to suppress a decrease in the melt tension and high-temperature strength of the molded article, making it less likely for deformation of the molded article due to water vapor pressure to occur and more likely to improve reflow heat resistance.

[0032] Furthermore, by including structural units derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms, the compatibility of the polyolefin copolymer (C) with the polyamide resin (A) and the halogenated flame retardant (B) can be improved. Thus, the presence of the polyolefin copolymer (C) at the interface between the polyamide resin (A) and the halogenated flame retardant (B) can prevent a decrease in interfacial strength. This makes it difficult for the interface to separate even when vapor pressure is generated by vaporization of the moisture contained therein. Therefore, deformation of the molded product due to water vapor pressure is further reduced, and reflow heat resistance is likely to be further improved.

[0033] By setting the content of the polyolefin copolymer (C) to 0.2% by mass or more relative to the content of the polyamide resin (A), the polyamide resin (A) can be sufficiently polymerized, thereby sufficiently increasing the melt tension, and thus facilitating the improvement of the reflow heat resistance of the molded article.

[0034] On the other hand, by setting the content of polyolefin copolymer (C) to 3.5% by mass or less relative to the content of polyamide resin (A), the content ratio of polyolefin copolymer (C), which has a relatively low melting point, in the resin composition is low, so the effect of improving melt tension due to higher molecular weight tends to dominate the effect of lowering the melting point of the molded product due to the addition of low-melting-point polyolefin copolymer (C), making it easier to improve the reflow heat resistance of the molded product.In addition, since excessively high molecular weight of polyamide resin (A) is unlikely to occur, compatibility with halogen-based flame retardant (B) is not excessively reduced, and it is thought that strand breakage during pelletization can be suppressed and processability into pellets can be improved.

[0035] 1-1. Polyamide resin (A) The polyamide resin (A) is a polyamide resin having a melting point of 280°C or higher as measured by a differential scanning calorimeter (DSC). The polyamide resin (A) forms crystals in the molded product, which can increase the mechanical strength (such as bending strength) of the molded product. Furthermore, since the polyamide resin (A) has a high melting point, it can be prevented from melting during the reflow process. The method for measuring the melting point of the polyamide resin (A) will be described later.

[0036] Examples of polyamide resins having a melting point of 280°C or higher include semi-aromatic polyamide resins and aliphatic polyamide resins having component units derived from an aliphatic diamine having four carbon atoms and component units derived from an aliphatic dicarboxylic acid having six carbon atoms (hereinafter also referred to as "aliphatic polyamide resins containing PA46"). Among these, the polyamide resin (A) is preferably a semi-aromatic polyamide resin. Note that the semi-aromatic polyamide is a polyamide containing structural units derived from a diamine and structural units derived from a dicarboxylic acid, in which the structural units derived from the diamine include structural units derived from an aliphatic diamine or structural units derived from an alicyclic diamine, and the structural units derived from the dicarboxylic acid include structural units derived from an aromatic dicarboxylic acid, or a polyamide in which the structural units derived from the diamine include structural units derived from an aromatic diamine, and the structural units derived from the dicarboxylic acid include structural units derived from an aliphatic dicarboxylic acid or structural units derived from an alicyclic dicarboxylic acid.

[0037] Examples of semi-aromatic polyamide resins include polyamide 6T6I, polyamide 6T66, polyamide 6TDT, etc., and among these, polyamide 6T66 is preferred.

[0038] The polyamide resin (A) is, for example, a polyamide resin containing a component unit (Aa) derived from a dicarboxylic acid and a component unit (Ab) derived from a diamine. Hereinafter, the polyamide resin containing the component unit (Aa) derived from a dicarboxylic acid and the component unit (Ab) derived from a diamine will be described.

[0039] 1-1-1. Dicarboxylic acid-derived component units (Aa) In the case of a semi-aromatic polyamide resin, the component units (Aa) derived from a dicarboxylic acid preferably include component units derived from an aromatic dicarboxylic acid, and more preferably include component units derived from terephthalic acid.

[0040] In the case of a semi-aromatic polyamide resin, the content of component units derived from aromatic dicarboxylic acids is preferably 40 mol% to 100 mol%, more preferably 50 mol% to 100 mol%, and even more preferably 60 mol% to 80 mol%, relative to the total number of moles of component units (Aa) derived from dicarboxylic acids.

[0041] In the case of a semi-aromatic polyamide resin, the content of component units derived from terephthalic acid is preferably 40 mol% to 100 mol%, more preferably 50 mol% to 100 mol%, even more preferably 60 mol% to 80 mol%, even more preferably 40 mol% to 65 mol%, and particularly preferably 55 mol% to 65 mol%, based on the total number of moles of component units (Aa) derived from dicarboxylic acids. If the content is 40 mol% or more, the aromatic ring concentration in the polyamide resin (A) increases, making the polyamide resin more susceptible to carbonization. This tends to improve the flame retardancy of the molded product.

[0042] The dicarboxylic acid-derived component unit (Aa) may contain other dicarboxylic acid-derived component units. Examples of other dicarboxylic acids include aromatic dicarboxylic acids other than terephthalic acid, aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. Of these, aliphatic dicarboxylic acids are preferred.

[0043] In the case of semi-aromatic polyamide resins, examples of the aliphatic dicarboxylic acids include aliphatic dicarboxylic acids having 4 to 20 carbon atoms. The number of carbon atoms is preferably 6 to 12. Examples of such aliphatic dicarboxylic acids include adipic acid, azelaic acid, and sebacic acid. Among these, adipic acid and sebacic acid are preferred, and adipic acid is more preferred.

[0044] In the case of a semi-aromatic polyamide resin, the content of the component units derived from the above-mentioned aliphatic dicarboxylic acid is preferably 0 mol% to 60 mol%, more preferably 30 mol% to 60 mol%, even more preferably 30 mol% to 45 mol%, and particularly preferably 35 mol% to 45 mol%, relative to the total number of moles of the component units (Aa) derived from the dicarboxylic acid.

[0045] Examples of the alicyclic dicarboxylic acid include cyclohexanedicarboxylic acid and its esters.

[0046] Examples of aromatic dicarboxylic acids other than terephthalic acid include isophthalic acid, 2-methylterephthalic acid, and naphthalenedicarboxylic acid.

[0047] In the case of a semi-aromatic polyamide resin, the content of component units derived from aromatic dicarboxylic acids other than terephthalic acid and alicyclic dicarboxylic acids is preferably 20 mol % to 80 mol %, and more preferably 25 mol % to 75 mol %, relative to the total number of moles of component units (Aa) derived from dicarboxylic acids.

[0048] In the case of an aliphatic polyamide resin, the content of component units derived from aliphatic dicarboxylic acids is preferably 80 mol% to 100 mol%, more preferably 90 mol% to 100 mol%, relative to the total number of moles of component units (Aa) derived from dicarboxylic acids, and even more preferably comprises substantially only aliphatic dicarboxylic acids. Note that, in this paragraph, "comprises substantially only aliphatic dicarboxylic acids" means that the content of component units derived from the aliphatic dicarboxylic acids is 99 mol% to 100 mol% relative to the total number of moles of component units (Aa) derived from dicarboxylic acids. Examples of the aliphatic dicarboxylic acids include aliphatic dicarboxylic acids having 4 to 20 carbon atoms. The number of carbon atoms is preferably 6 to 12. Examples of such aliphatic dicarboxylic acids include adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodiumsulfoisophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, diglycolic acid, etc. Among these, adipic acid and sebacic acid are preferred, and adipic acid is more preferred.

[0049] In the case of an aliphatic polyamide resin including PA46, the dicarboxylic acid-derived unit (Aa) may include an alicyclic dicarboxylic acid-derived unit. Examples of the alicyclic dicarboxylic acid include cyclohexanedicarboxylic acid and its esters.

[0050] 1-1-2. Diamine-derived component units (Ab) The diamine-derived component unit (Ab) includes, for example, a component unit derived from an aliphatic diamine having 4 to 15 carbon atoms, a component unit derived from an alicyclic diamine having 4 to 20 carbon atoms, and a component unit derived from an aromatic diamine.

[0051] The number of carbon atoms in the aliphatic diamine is preferably 4 to 12. Examples of the aliphatic diamine include linear alkylenediamines and branched alkylenediamines.

[0052] Examples of the linear alkylenediamine include 1,4-diaminobutane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane. Among these, in the case of semi-aromatic polyamide resins, 1,6-diaminohexane, 1,9-nonanediamine, and 1,10-diaminodecane are preferred, with 1,6-diaminohexane being more preferred. In the case of aliphatic polyamide resins containing PA46, 1,4-diaminobutane is preferred. The linear alkylenediamine may be contained alone or in combination of two or more types.

[0053] Examples of the branched alkylenediamine include 2,2-dimethyldiaminopropane, 1,1-dimethyl-1,4-diaminobutane, 1-ethyl-1,4-diaminobutane, 1,2-dimethyl-1,4-diaminobutane, 1,3-dimethyl-1,4-diaminobutane, 1,4-dimethyl-1,4-diaminobutane, 2,3-dimethyl-1,4-diaminobutane, 2-methyl-1,5-diaminopentane, 2,5-dimethyl-1,6-diaminohexane, 2,4 -Dimethyl-1,6-diaminohexane, 3,3-dimethyl-1,6-diaminohexane, 2,2-dimethyl-1,6-diaminohexane, 2,2,4-trimethyl-1,6-diaminohexane, 2,4,4-trimethyl-1,6-diaminohexane, 2,4-diethyl-1,6-diaminohexane, 2,3-dimethyl-1,7-diaminoheptane, 2,4-dimethyl-1,7-diaminoheptane, 2,5-dimethyl-1,7-diaminoheptane, 2,2- Dimethyl-1,7-diaminoheptane, 2-methyl-4-ethyl-1,7-diaminoheptane, 2-ethyl-4-methyl-1,7-diaminoheptane, 2,2,5,5-tetramethyl-1,7-diaminoheptane, 3-isopropyl-1,7-diaminoheptane, 3-isooctyl-1,7-diaminoheptane, 2-methyl-1,8-diaminooctane, 1,3-dimethyl-1,8-diaminooctane, 1,4-dimethyl-1,8-diaminooctane, 2 ,4-dimethyl-1,8-diaminooctane, 3,4-dimethyl-1,8-diaminooctane, 4,5-dimethyl-1,8-diaminooctane, 2,2-dimethyl-1,8-diaminooctane, 3,3-dimethyl-1,8-diaminooctane, 4,4-dimethyl-1,8-diaminooctane, 3,3,5-trimethyl-1,8-diaminooctane, 2,4-diethyl-1,8-diaminooctane, and 5-methyl-1,9-diaminononane. Among these, 2-methyl-1,8-diaminooctane is preferred.

[0054] In the case of semi-aromatic polyamide resins, the content of the component units derived from the aliphatic diamine is preferably 30 mol% to 100 mol%, and more preferably 70 mol% to 100 mol%, relative to the total number of moles of the component units (Ab) derived from the diamine. In the case of aliphatic polyamide resins, the content of the component units derived from the aliphatic diamine is preferably 80 mol% to 100 mol%, and more preferably 90 mol% to 100 mol%, relative to the total number of moles of the component units (Ab) derived from the diamine, and it is even more preferable that the polyamide resin contains substantially only aliphatic diamines. In this paragraph, "containing substantially only aliphatic diamines" means that the content of the component units derived from the aliphatic diamine is 99 mol% to 100 mol%, relative to the total number of moles of the component units (Ab) derived from the diamine.

[0055] Examples of the alicyclic diamine having 4 to 20 carbon atoms include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 1,3-bis(aminomethyl)cyclohexane, 2,5-bisaminomethylnorbornane, and 2,6-bisaminomethylnorbornane, etc. Examples of the aromatic diamine include metaxylylenediamine, etc.

[0056] In the case of a semi-aromatic polyamide resin, the content of the component units derived from the above-mentioned alicyclic diamine and aromatic diamine is preferably 0 mol % to 70 mol %, more preferably 0 mol % to 30 mol %, relative to the total number of moles of the component units (Ab) derived from diamine.

[0057] The respective structural units of the polyamide resin (A) and their ratios can be calculated from the charge ratios when the polyamide resin (A) is prepared, or can be measured by the NMR method.

[0058] 1 In the case of H-NMR measurement, for example, a nuclear magnetic resonance apparatus (ECX400 model manufactured by JEOL Ltd.) is used, the solvent is deuterated orthodichlorobenzene, the sample concentration is 20 mg / 0.6 mL, the measurement temperature is 120 °C, and the observation nucleus is 1The conditions are H (400 MHz), sequence is single pulse, pulse width is 5.12 μsec (45° pulse), repetition time is 7.0 sec, and the number of accumulations is 500 or more. The reference chemical shift is set to 0 ppm for hydrogen in tetramethylsilane, but similar results can also be obtained by setting the peak derived from residual hydrogen in deuterated orthodichlorobenzene at 7.10 ppm as the reference value for the chemical shift. 1 Peaks such as H can be assigned by conventional methods.

[0059] 13 In the case of C-NMR measurement, for example, a nuclear magnetic resonance apparatus (ECP500 model manufactured by JEOL Ltd.) is used as the measurement apparatus, a mixed solvent of ortho-dichlorobenzene / heavy benzene (80 / 20% by volume) is used as the solvent, the measurement temperature is 120°C, and the observation nucleus is 13 The conditions were: C (125 MHz), single pulse proton decoupling, 45° pulse, repetition time 5.5 seconds, accumulation number 10,000 or more, and chemical shift reference value 27.50 ppm. Assignment of various signals was performed based on the standard method, and quantification could be performed based on the accumulated value of signal intensity.

[0060] The dicarboxylic acid-derived component units of the polyamide resin (A) may include component units derived from biomass-derived dicarboxylic acids, and the diamine-derived component units may include component units derived from biomass-derived diamines. The polyamide resin (A) may also be a biomass-derived polyamide resin (A) obtained by polymerizing raw materials including biomass-derived raw materials.

[0061] 1-1-3. Physical properties of polyamide resin (A) From the viewpoint of further increasing the mechanical strength of the molded article, the melting point of the polyamide resin (A) is 280° C. or higher, preferably 290° C. or higher, and more preferably 300° C. or higher. Furthermore, from the viewpoint of suppressing decomposition of the amide bond of the polyamide resin (A), the melting point of the polyamide resin (A) is preferably 330° C. or lower.

[0062] The melting point of the polyamide resin (A) can be adjusted to the above range by adjusting the composition of the polyamide resin (A). For example, the melting point can be increased by increasing the content of component units derived from terephthalic acid.

[0063] The polyamide resin (A) preferably has a glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) of 70°C to 145°C, more preferably 75°C to 125°C, and even more preferably 80°C to 100°C. A glass transition temperature (Tg) of 70°C or higher increases the temperature at which molecular mobility becomes active in a high-temperature environment, thereby suppressing molecular mobility and further suppressing blister formation. As a result, reflow heat resistance can be further improved. A glass transition temperature (Tg) of 145°C or lower can easily maintain the fluidity of the resin composition without excessively increasing the mold temperature during molding, thereby improving molding processability.

[0064] The heat of fusion (ΔH) of the polyamide resin (A) measured by differential scanning calorimetry (DSC) is preferably greater than 5 J / g, and more preferably greater than 5 J / g and not greater than 100 J / g. The heat of fusion is an indicator of the crystallinity of a resin, with a larger heat of fusion indicating higher crystallinity. When the heat of fusion (ΔH) of the polyamide resin (A) exceeds 5 J / g, the crystallinity is increased, thereby enabling the mechanical strength (such as bending strength) of the resulting molded article to be increased. When the heat of fusion (ΔH) of the polyamide resin (A) is 100 J / g or less, molding shrinkage can be suppressed, and the dimensional accuracy of the resulting molded article can be improved.

[0065] The melting point and heat of fusion (ΔH) of polyamide resin (A) are measured using a differential scanning calorimeter (DSC220C, manufactured by Seiko Instruments Inc.). Specifically, approximately 5 mg of polyamide resin (A) is sealed in a measuring aluminum pan and heated from room temperature to 350°C at 10°C / min. To completely melt the resin, the pan is held at 350°C for 3 minutes and then cooled to 30°C at 10°C / min. After leaving the pan at 30°C for 5 minutes, the pan is heated a second time to 350°C at 10°C / min. The temperature (°C) of the endothermic peak during this second heating is taken as the melting point (Tm) of polyamide resin (A), and the inflection point corresponding to the glass transition is taken as the glass transition temperature (Tg). The heat of fusion (ΔH) is calculated from the area of ​​the endothermic peak during the first heating process, in accordance with JIS K7122:2012.

[0066] The intrinsic viscosity [η] of the polyamide resin (A), measured in 96.5% sulfuric acid at 25°C, is preferably 0.7 dL / g to 1.2 dL / g, more preferably 0.75 dL / g to 1.1 dL / g, even more preferably 0.75 dL / g to 1.0 dL / g, and particularly preferably 0.8 dL / g to 1.0 dL / g. When the intrinsic viscosity [η] of the polyamide resin (A) is 0.7 dL / g or higher, the mechanical strength (e.g., bending strength) of the molded article is easily increased, while when it is 1.2 dL / g or lower, the fluidity of the resin composition during molding is less likely to be impaired. The intrinsic viscosity [η] can be adjusted by adjusting the molar ratio of the dicarboxylic acid-derived component unit (Aa) to the diamine-derived component unit (Ab). Specifically, the closer the molar ratio of the carboxylic acid-derived component unit (Aa) to the diamine-derived component unit (Ab) is to 1:1, the higher the intrinsic viscosity can be. It can also be adjusted by the amount of end-capping of the polyamide resin (A).

[0067] The intrinsic viscosity [η] of polyamide resin (A) is a value measured as follows: 0.5 g of polyamide resin (A) is dissolved in 50 ml of 96.5% sulfuric acid solution to prepare a sample solution. The flow time of the obtained solution at 25°C ± 0.05°C is measured using an Ubbelohde viscometer, and the intrinsic viscosity [η] is calculated according to the following formula: [η]=ηSP / (C*(1+0.205ηSP)) [η]: Intrinsic viscosity (dl / g) ηSP: Specific viscosity C: Sample concentration (g / dl) t: Number of seconds for sample solution to flow down (seconds) t0: Number of seconds the blank sulfuric acid flows (seconds) ηSP=(t-t0) / t0

[0068] The polyamide resin (A) can be produced by the same method as that for known polyamide resins, for example, by polycondensing a dicarboxylic acid and a diamine in a homogeneous solution. Specifically, the polyamide resin (A) can be produced by heating a dicarboxylic acid and a diamine in the presence of a catalyst to obtain a low-order condensate, as described in WO 03 / 085029, and then applying shear stress to a melt of the low-order condensate to polycondense it.

[0069] The amount of terminal carboxy groups in the polyamide resin (A) is preferably 20 mmol / kg to 200 mmol / kg, and more preferably 40 mmol / kg to 170 mmol / kg. When the amount of terminal carboxy groups is 20 mmol / kg or more, the reaction with glycidyl groups proceeds sufficiently, thereby improving the melt tension of the molded article and facilitating enhanced reflow heat resistance. When the amount of terminal carboxy groups is 200 mmol / kg or less, there are fewer terminal carboxy groups that can act as acid catalysts to promote thermal decomposition during heating, which makes it easier to suppress molecular weight reduction due to thermal decomposition and more easily suppresses the occurrence of blisters.

[0070] The amount of terminal carboxyl groups is a value measured using NMR. Specifically, for example, 30 mg of polyamide resin is dissolved in 0.5 mL of deuterated hexafluoroisopropanol (HFIP) to prepare a sample for NMR measurement. NMR measurement of the prepared sample is performed using a nuclear magnetic resonance spectrometer (ECA-500, manufactured by JEOL Ltd.). The molecular weight of the polyamide resin is calculated from the peak areas of hydrogen atoms of each component constituting the polyamide resin in the obtained spectrum. The amount of terminal carboxyl groups ([COOH], unit: mmol / kg) is calculated using the peak areas of hydrogen atoms specific to the terminal carboxyl groups and the molecular weight value.

[0071] The amount of terminal amino groups in the polyamide resin (A) is preferably 30 mmol / kg to 200 mmol / kg, more preferably 50 mmol / kg to 200 mmol / kg, and even more preferably 50 mmol / kg to 150 mmol / kg. When the amount of terminal amino groups is 30 mmol / kg or more, the reaction with glycidyl groups proceeds sufficiently, thereby improving the melt tension of the molded article and facilitating the enhancement of reflow heat resistance. For the same reason, when the amount of terminal amino groups is 50 mmol / kg or more, the reflow heat resistance can be further enhanced. When the amount of terminal amino groups is 200 mmol / kg or less, the reaction with glycidyl groups is less likely to proceed excessively, thereby facilitating the enhancement of moldability into pellets.

[0072] The amount of terminal amino groups is measured by the following method. 1 g of polyamide resin is dissolved in 35 mL of phenol, and 2 mL of methanol is added to prepare a sample solution. Using thymol blue as an indicator, the sample solution is titrated with a 0.01 N hydrochloric acid solution using a potentiometric titrator (Metrohm) until the solution turns from blue to yellow, and the amount of terminal amino groups ([NH2], unit: mmol / kg) is measured.

[0073] The content of polyamide resin (A) is preferably 20% by mass to 80% by mass, more preferably 30% by mass to 70% by mass, and more preferably 35% by mass to 60% by mass, based on the total mass of the polyamide resin composition. When the content is 20% by mass or more, the bending strength and toughness of the polyamide resin composition can be further increased. When the content is 80% by mass or less, other components such as the halogen-based flame retardant (B) and flame retardants described below can be sufficiently contained in the polyamide resin composition.

[0074] 1-2. Halogen-based flame retardants (B) The halogen-based flame retardant (B) can impart flame retardancy to the polyamide resin composition and its molded article, and contains a halogen.

[0075] Examples of the halogen-based flame retardant (B) include brominated polystyrene, polybrominated styrene, brominated polyphenylene ether, etc. Among these, the halogen-based flame retardant (B) preferably includes brominated polystyrene and / or polybrominated styrene, and more preferably includes brominated polystyrene.

[0076] Brominated polystyrene is a brominated polystyrene or poly-α-methylstyrene. In the brominated polystyrene, some of the hydrogen atoms bonded to the carbon atoms forming the aromatic ring are substituted with bromine atoms, and it is preferable that the hydrogen atoms forming the alkyl chain forming the main skeleton of the polymer are not substantially substituted with bromine atoms. The bromine content of the brominated polystyrene is The content is preferably 55% by mass to 71% by mass, and more preferably 65% ​​by mass to 70% by mass.

[0077] "Hydrogen atoms forming the alkyl chain that forms the main skeleton of the polymer are not substantially substituted with bromine atoms" means that the proportion of hydrogen atoms forming the alkyl chain that forms the main skeleton of the polymer that are substituted with bromine atoms is preferably 0.0% to 0.5% by mass, more preferably 0.0% to 0.2% by mass, and even more preferably 0.0% to 0.1% by mass. By setting the proportion in this range, thermal stability tends to be improved.

[0078] The weight-average molecular weight (Mw) of the brominated polystyrene is preferably 1,000 to 300,000, and more preferably 2,000 to 100,000. When Mw is within the above range, high fluidity is easily obtained during molding without impairing toughness, etc. The weight-average molecular weight is a value calculated in terms of polystyrene, measured using gel permeation chromatography (GPC) with chloroform as the mobile phase and a differential refractometer detector at a column temperature of 40°C.

[0079] The melt flow rate (MFR) of the brominated polystyrene is preferably 0.1 g / 10 min to 1000 g / 10 min, and more preferably 0.1 g / 10 min to 900 g / 10 min. The MFR is a value measured under conditions of a load of 1200 g, a temperature of 270°C, and an orifice inner diameter of 2.095 mm. The MFR can also be measured under conditions of a load of 2160 g, a temperature of 220°C, and an orifice inner diameter of 2.095 mm, and in this case, the MFR is preferably 0.001 g / 10 min to 15 g / 10 min.

[0080] The content of the halogen-based flame retardant (B) is preferably 10% by mass to 50% by mass, and more preferably 15% by mass to 45% by mass, based on the total mass of the polyamide resin composition. A content of 10% by mass or more can further enhance the flame retardancy of the polyamide resin composition and its molded article. Furthermore, a content of 50% by mass or less can further enhance the reflow heat resistance of the polyamide resin composition and its molded article.

[0081] 1-3. Polyolefin copolymer (C) The polyolefin copolymer (C) according to this embodiment contains structural units derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms, and structural units containing a glycidyl group.

[0082] Examples of the α-olefin having 3 to 8 carbon atoms include linear α-olefins such as propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene.

[0083] Among these, the structural unit derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms is preferably a structural unit derived from ethylene.

[0084] The structural unit containing a glycidyl group may be a structural unit derived from an unsaturated carboxylic acid glycidyl ester, a structural unit derived from a glycidyl ether having an unsaturated group, or a combination thereof. The structural unit containing a glycidyl group is present at least in the main chain of the polyolefin copolymer (C). The structural unit containing a glycidyl group may or may not be present at the terminal of the polyolefin copolymer (C).

[0085] Examples of unsaturated carboxylic acid glycidyl esters include glycidyl (meth)acrylate and itaconic acid glycidyl ester. The term "(meth)acrylate" refers to acrylate, methacrylate, or both. Examples of glycidyl ethers having an unsaturated group include allyl glycidyl ether, 2-methylallyl glycidyl ether, and styrene-p-glycidyl ether. Among these, the structural unit containing a glycidyl group is preferably an unsaturated carboxylic acid glycidyl ester, and more preferably a structural unit derived from glycidyl (meth)acrylate.

[0086] The polyolefin copolymer (C) may further contain structural units derived from a (meth)acrylic acid ester and / or structural units derived from a vinyl ether (excluding structural units containing a glycidyl group) in addition to structural units derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms and structural units containing a glycidyl group.

[0087] Examples of (meth)acrylic acid esters include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, and butyl (meth)acrylate.

[0088] Examples of vinyl ethers include methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, and phenyl vinyl ether.

[0089] Examples of the polyolefin copolymer (C) include ethylene-glycidyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-methyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-ethyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-normal propyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-isopropyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-normal butyl (meth)acrylate copolymer, ethylene-glycidyl (meth)acrylate-isobutyl (meth)acrylate copolymer, and ethylene-glycidyl (meth)acrylate-vinyl ether copolymer. Among these, the polyolefin copolymer (C) is preferably an ethylene-glycidyl (meth)acrylate copolymer. The ethylene-glycidyl (meth)acrylate copolymer has high compatibility with the polyamide resin (A) and the halogen-based flame retardant (B), and thus is easily dispersible in the polyamide resin composition. In addition, the ethylene-glycidyl (meth)acrylate copolymer has a relatively high melting point compared to other polyolefin-based copolymers (C), and therefore is easily able to improve the reflow heat resistance of the polyamide resin composition.

[0090] With respect to 100% by mass of all structural units constituting the polyolefin copolymer (C), the mass of the structural units derived from the above-mentioned ethylene or α-olefin monomer having 3 to 8 carbon atoms is preferably 95% by mass or less, more preferably 90% by mass to 95% by mass, and even more preferably 90% by mass to 93% by mass.

[0091] The mass of the structural unit containing the glycidyl group is preferably 5% by mass or more, more preferably 5 to 10% by mass, and even more preferably 7 to 10% by mass, relative to 100% by mass of all structural units constituting the polyolefin copolymer (C). By making it 5% by mass or more, it is possible to easily react with both terminal groups of the polyamide to increase the molecular weight. By making it 7% by mass or more, it is possible to further enhance the reactivity. Furthermore, by making it 10% by mass or less, it is possible to suppress a rapid increase in viscosity due to a three-dimensional crosslinking reaction.

[0092] The polyolefin copolymer (C) preferably contains 3.0% by mass or less of structural units other than the ethylene-derived structural units or the glycidyl (meth)acrylate-derived structural units, and preferably contains substantially no structural units other than the ethylene-derived structural units or the glycidyl (meth)acrylate-derived structural units. This embodiment can improve compatibility with polyamides and brominated polystyrene. The term "substantially free" means that the content of structural units other than the ethylene-derived structural units or the glycidyl (meth)acrylate-derived structural units is 1.0% by mass or less, based on the total mass of the polyolefin copolymer (C).

[0093] The ratio of the molar amount of the structural unit having a glycidyl group in the polyolefin copolymer (C) contained in the polyamide resin composition as the numerator to the total molar amount of the terminal carboxyl group in the polyamide resin (A) contained in the polyamide resin composition and the terminal amino group in the polyamide resin (A) as the denominator is preferably 0.3 / 1.0 to 10.0 / 1.0, more preferably 1.0 / 1.0 to 10.0 / 1.0, even more preferably 1.0 / 1.0 to 4.5 / 1.0, and most preferably 1.0 / 1.0 to 2.5 / 1.0. The glycidyl groups in the polyolefin copolymer (C) can react with the terminal carboxyl groups and terminal amino groups of the polyamide resin (A) and the amide groups in the molecular chain. When the molecular ratio is 0.3 or more, the molar content of the glycidyl groups relative to the highly reactive terminal carboxyl groups and terminal amino groups increases, which facilitates the polyamide resin (A) to be polymerized and improves its reflow heat resistance. When the molecular ratio is 1.0 or more, sufficient glycidyl groups are present, which facilitates the polyamide resin (A) to be polymerized and improves its reflow heat resistance. When the molecular ratio is 10.0 or less, it is easy to suppress a rapid increase in viscosity due to a three-dimensional crosslinking reaction.

[0094] The molar amount (unit: mmol) of the structural unit having a glycidyl group in the polyolefin copolymer (C) contained in the polyamide resin composition is a value obtained by multiplying the value (unit: mmol / kg) calculated by measuring the molar amount of the structural unit having a glycidyl group in the polyolefin copolymer (C) by potentiometric titration (JIS K7236:2001) by the content (unit: kg) of the polyolefin copolymer (C).

[0095] The total molar amount (unit: mmol) of the amount of terminal carboxy groups in the polyamide resin (A) and the amount of terminal amino groups in the polyamide resin (A) contained in the polyamide resin composition is calculated by multiplying the total amount (unit: mmol / kg) of the amount of terminal carboxy groups and the amount of terminal amino groups determined by the above-mentioned quantitative method using the polyamide resin (A) by the content (unit: kg) of the polyamide resin (A).

[0096] The melt flow rate (MFR) of the polyolefin copolymer (C) is preferably 0.2 g / 10 min to 300 g / 10 min, more preferably 0.5 g / 10 min to 250 g / 10 min, even more preferably 1.0 g / 10 min to 220 g / 10 min, even more preferably 1.5 g / min to 200 g / 10 min, even more preferably 2.0 g / 10 min to 200 g / 10 min, even more preferably 2.5 g / 10 min to 200 g / 10 min, and most preferably 3.0 g / 10 min to 200 g / 10 min. The MFR of the polyolefin copolymer (C) is a value measured in accordance with JIS K7210-1:2014 under conditions of a temperature of 190 ° C and a load of 2.16 kgf.

[0097] Furthermore, the polyolefin copolymer (C) preferably has a melting point measured by differential scanning calorimetry (DSC) of 50°C or higher, more preferably 100°C or higher, and even more preferably 100°C to 120°C. A melting point of 50°C or higher increases the temperature at which molecular mobility becomes active in a high-temperature environment, thereby suppressing molecular mobility and further suppressing blister formation. As a result, reflow heat resistance can be further improved. A melting point of 100°C or higher further enhances the effect of suppressing molecular mobility, making it easier to further improve reflow heat resistance. A melting point of 120°C or lower can provide advantageous processability and high-frequency sealability.

[0098] The melting point of the polyolefin copolymer (C) is a value measured using a differential scanning calorimeter (DSC220C, manufactured by Seiko Instruments Inc.). Specifically, approximately 5 mg of the polyolefin copolymer (C) is sealed in a measuring aluminum pan and heated from room temperature to 150°C at 10°C / min. To completely melt the resin, the pan is held at 150°C for 3 minutes and then cooled to 30°C at 10°C / min. After leaving the pan at 30°C for 5 minutes, the pan is heated a second time to 150°C at 10°C / min. The temperature (°C) of the endothermic peak during this second heating is taken as the melting point (Tm) of the polyolefin copolymer (C).

[0099] The content of the polyolefin copolymer (C) is 0.2 to 3.5% by mass, preferably 1.4 to 3.3% by mass, when the content of the polyamide resin (A) is taken as 100% by mass. By making it 1.4% by mass or more, the polyamide resin (A) is more likely to be increased in molecular weight, making it easier to improve reflow heat resistance. By making it 3.3% by mass or less, it is possible to suppress a sudden increase in viscosity due to a three-dimensional crosslinking reaction.

[0100] The content of the polyolefin copolymer (C) is preferably 0.10% by mass to 1.50% by mass, and more preferably 0.62% by mass to 1.40% by mass, based on the total mass of the polyamide resin composition. By setting the content to 0.10% by mass or more, sufficient glycidyl groups are present, which allows the polyamide resin (A) to be sufficiently polymerized and makes it easier to improve reflow heat resistance. By setting the content to 1.40% by mass or less, it is easier to suppress a rapid increase in viscosity due to a three-dimensional crosslinking reaction.

[0101] The polyolefin copolymer (C) can be synthesized by known synthesis methods, such as bulk polymerization using a free radical initiator, emulsion polymerization, and solution polymerization.

[0102] As described above, the glycidyl groups of the polyolefin copolymer (C) react with the terminal carboxy groups, terminal amino groups, and amide groups in the molecular chain of the polyamide resin (A). Therefore, at least a portion of the polyolefin copolymer (C) may be present in a state chemically bonded to the polyamide resin (A). That is, the polyamide resin composition according to this embodiment may contain a polyamide resin (A') obtained by chemically reacting the glycidyl groups of the polyolefin copolymer (C) with at least one group selected from the group consisting of a carboxy group, an amino group, and an amide group of the polyamide resin (A).

[0103] In addition to the various components of the polyamide resin (A) as described above, the polyamide resin (A') may have at least one partial structure represented by any of the following formulas (1) to (3). Formula (1) is a partial structure obtained by reacting a glycidyl group in the polyolefin copolymer (C) with a carboxy group in the polyamide resin (A). Formula (2) is a partial structure obtained by reacting a glycidyl group in the polyolefin copolymer (C) with an amino group in the polyamide resin (A). Formula (3) is a partial structure obtained by reacting a glycidyl group in the polyolefin copolymer (C) with an amide group in the polyamide resin (A). In formulas (1) to (3), * represents a bonding position.

[0104] When the polyamide resin composition contains polyamide resin (A'), the content of polyamide resin (A) is the sum of the molar amount of polyamide resin (A) and the molar amount of polyamide resin (A') multiplied by the number average molecular weight of polyamide resin (A). The number average molecular weight of polyamide resin (A) is measured using gel permeation chromatography (GPC) with chloroform as the mobile phase at a column temperature of 40°C using a differential refractometer detector, and is a value calculated in terms of polystyrene.

[0105] [ka]

[0106] [ka]

[0107] [ka]

[0108] 1-4.Other ingredients The polyamide resin composition may contain other known components.

[0109] Examples of other components include flame retardant synergists, reinforcing agents, nucleating agents, lubricants, anti-drip agents, halogen scavengers, colorants, heat stabilizers, corrosion resistance improvers, anti-drip agents, ion scavengers, elastomers (rubbers), antistatic agents, mold release agents, antioxidants (phenols, amines, sulfurs, phosphorus compounds, etc.), heat stabilizers other than those mentioned above (lactone compounds, vitamin E compounds, hydroquinones, etc.), light stabilizers (benzotriazoles, triazines, benzophenones, benzoates, hindered amines, oxanilides, etc.), polymers (not containing epoxy groups) other than polyolefin copolymer (C) (olefin copolymers such as ethylene-propylene copolymers, ethylene-1-butene copolymers, olefin copolymers such as propylene-1-butene copolymers, polystyrene, polycarbonate, polyacetal, polysulfone, polyphenylene oxide, fluororesin, silicone resin, LCP, etc.).

[0110] (Flame retardant synergist) Any known flame retardant aid can be used as long as it significantly enhances the flame retardant effect when used in combination with the halogen-based flame retardant (B). Specific examples include antimony compounds such as antimony trioxide, antimony tetraoxide, antimony pentoxide, and sodium antimonate; zinc borates such as 2ZnO·3B2O3, 4ZnO·B2O3·H2O, and 2ZnO·3B2O3·3.5H2O; zinc stannate; zinc phosphate; calcium borate; and calcium molybdate. These aids may be used alone or in combination. Among these, sodium antimonate, zinc borate, zinc phosphate, and zinc stannate are preferred, with sodium antimonate and anhydrous zinc borate (2ZnO·3B2O3) being more preferred.

[0111] The content of the flame retardant aid is preferably 0.5 to 5.0% by mass, and more preferably 1.0 to 3.0% by mass, based on the total mass of the polyamide resin composition.

[0112] (Reinforcement material) Reinforcing agents can impart higher tensile strength to polyamide resin compositions and molded articles. Reinforcing agents are broadly divided into reinforcing agents (1) (hereinafter simply referred to as "reinforcing agent (1)") having a cross-sectional aspect ratio of 1.5 or more and reinforcing agents (2) (hereinafter simply referred to as "reinforcing agent (2)") having a cross-sectional aspect ratio of less than 1.5. Either of these may be used, but reinforcing agent (1) is preferred. In this specification, the "cross section" of a reinforcing agent refers to a cross section cut in a direction perpendicular to the longitudinal direction of the fiber. The "aspect ratio" refers to the value of the ratio of the first line segment to the second line segment, where the longest line segment passing through the center of the cross section and connecting opposing edges in the cross section is defined as the first line segment and the line segment perpendicular to the longest line segment is defined as the second line segment.

[0113] (Reinforcement material (1)) The cross-sectional aspect ratio of the reinforcing material (1) is preferably 2.0 or more, more preferably 2.5 or more, and even more preferably 3.0 or more. An aspect ratio of 2.0 or more increases the length of the reinforcing material (1) in the direction perpendicular to its longitudinal direction (the flow direction of the polyamide resin composition during molding). Therefore, the volumetric shrinkage of the molded body in the flow direction as well as in the perpendicular direction can be further suppressed. As a result, the difference in volumetric shrinkage rate between the flow direction and the perpendicular direction can be further reduced, thereby further suppressing warpage of the molded body immediately after molding and after reflow treatment. For the same reason, an aspect ratio of 3.0 or more can more sufficiently suppress warpage. The upper limit of the aspect ratio is, for example, 8.0. The aspect ratio can be determined by determining the weight-average major axis (Dw) and weight-average minor axis (dw) using the method described below and calculating the ratio (Dw / dw) between them. The cross-sectional shape of the reinforcing material (1) is, for example, elliptical or flat.

[0114] The type of reinforcing material (1) is not particularly limited, and examples thereof include glass fiber, carbon fiber, wollastonite, potassium titanate whisker, calcium carbonate whisker, aluminum borate whisker, magnesium sulfate whisker, sepiolite, xonotlite, zinc oxide whisker, milled fiber, cut fiber, wholly aromatic polyamide fiber (e.g., polyparaphenylene terephthalamide fiber, polymetaphenylene terephthalamide fiber, polyparaphenylene isophthalamide fiber, polymetaphenylene isophthalamide fiber, and fiber obtained from a condensate of diaminodiphenyl ether with terephthalic acid or isophthalic acid), boron fiber, liquid crystal polyester fiber, etc. Among these, glass fiber and carbon fiber are preferred, and glass fiber is more preferred, because they tend to increase the strength (rigidity) and heat resistance of the resulting polyamide resin composition.

[0115] The average fiber diameter (weight average major axis (Dw)) of the reinforcing material (1) is, for example, 1 μm to 50 μm, and preferably 5 μm to 30 μm. The average fiber length of the reinforcing material (1) is, for example, 10 μm to 3000 μm, and preferably 100 μm to 1000 μm. In this specification, the term "fiber diameter" refers to the length of the longest line segment (the first line segment) among the line segments connecting opposing edges in the cross section of the fibrous reinforcing material.

[0116] The average fiber length of the reinforcing material (1) can be measured by the following method. 1) The polyamide resin composition is dissolved in a hexafluoroisopropanol / chloroform solution (0.1 / 0.9% by volume), and then filtered to obtain a filtrate. 2) The filtered material obtained in 1) above is dispersed in water, and the major and minor diameters (the major diameter is Di and the minor diameter is di. Here, the major diameter refers to the first line segment in the fiber cross section, and the minor diameter refers to the second line segment) and fiber length (Li) of each of 300 randomly selected fibers are measured using an optical microscope (magnification: 50x). The number of fibers with a fiber length of Li is designated as qi, and the weight-average length (Lw) is calculated based on the following formula, which is the average fiber length of the reinforcement (1). Weight average length (Lw) = (Σqi × Li 2 ) / (Σqi×Li) Similarly, the number of fibers with a major diameter Di is defined as Ri, and the number of fibers with a minor diameter di is defined as ri. The weight-average diameters (weight-average major diameter Dw, weight-average minor diameter dw) are calculated based on the following formula, and these are defined as the average major diameter and average minor diameter of the reinforcing material (1). Weight average major axis (Dw) = (ΣRi × Di 2 ) / (ΣRi×Di) Weight average short diameter (dw)=(Σri×di 2 ) / (Σri×di)

[0117] When the polyamide resin composition contains both reinforcing material (1) and reinforcing material (2), the content of reinforcing material (1) is 15% by mass to 85% by mass, preferably 30% by mass to 85% by mass, more preferably 40% by mass to 85% by mass, even more preferably 50% by mass to 85% by mass, and particularly preferably 50% by mass to 70% by mass, based on the total mass of reinforcing material (1) and reinforcing material (2). When the content is 50% by mass or more, volumetric shrinkage of the molded article in the flow direction as well as in the perpendicular direction can be further suppressed. As a result, warpage of the molded article immediately after molding and after reflow treatment can be further suppressed.

[0118] (Reinforcement material (2)) The cross-sectional aspect ratio of the reinforcing material (2) is preferably 1.0 or more and less than 1.5, more preferably 1.0 or more and 1.3 or less. The aspect ratio of the reinforcing material (2) can be determined in the same manner as for the reinforcing material (1). The cross-sectional shape of the reinforcing material (2) is, for example, elliptical or circular, and is preferably circular.

[0119] The type of reinforcing material (2) is not particularly limited, and examples thereof include glass fiber, carbon fiber, wollastonite, potassium titanate whisker, calcium carbonate whisker, aluminum borate whisker, magnesium sulfate whisker, sepiolite, xonotlite, zinc oxide whisker, milled fiber, cut fiber, wholly aromatic polyamide fiber (e.g., polyparaphenylene terephthalamide fiber, polymetaphenylene terephthalamide fiber, polyparaphenylene isophthalamide fiber, polymetaphenylene isophthalamide fiber, and fiber obtained from a condensate of diaminodiphenyl ether with terephthalic acid or isophthalic acid), boron fiber, liquid crystal polyester fiber, etc. Among these, glass fiber and carbon fiber are preferred, and glass fiber is more preferred, because they tend to increase the strength (rigidity) and heat resistance of the resulting polyamide resin composition.

[0120] The average fiber diameter (weight average major axis (Dw)) of the reinforcing material (2) is, for example, 1 μm to 50 μm, preferably 5 μm to 30 μm, and more preferably 5 μm to 20 μm. The average fiber length of the reinforcing material (2) is, for example, 500 μm to 10 mm, and preferably 700 μm to 5 mm. The average fiber diameter and the average fiber length can be measured in the same manner as described for the reinforcing material (1).

[0121] When the polyamide resin composition contains both the reinforcement (1) and the reinforcement (2), the content of the reinforcement (2) is 15% by mass to 85% by mass, preferably 15% by mass to 70% by mass, more preferably 15% by mass to 60% by mass, even more preferably 15% by mass to 50% by mass, and even more preferably 30% by mass to 50% by mass, based on the total mass of the reinforcement (1) and the reinforcement (2).

[0122] The reinforcing material may be bundled with a sizing agent. Examples of the sizing agent include acrylic, acrylic / maleic acid-modified, epoxy, urethane, urethane / maleic acid-modified, and urethane / epoxy-modified compounds. The sizing agents may be used alone or in combination. Of these, urethane-based compounds are preferred.

[0123] The total mass of the reinforcing material is preferably 20.00% by mass to 40.00% by mass, and more preferably 25.00% by mass to 35.00% by mass, relative to the total mass of the polyamide resin composition. A content of 20.00% by mass or more can further increase the strength of a molded article of the polyamide resin composition. This makes the molded article less susceptible to deformation during reflow treatment, and reduces the likelihood of blistering. As a result, reflow heat resistance can be further improved. Furthermore, a content of 40.00% by mass or less can easily reduce the total contact area between the polyamide resin (A) and the reinforcing material. This can easily reduce the interface area between the reinforcing material, which is a fragile layer, and the polyamide resin (A), thereby more easily suppressing the occurrence of blisters at the interface between the polyamide resin (A) and the reinforcing material. In other words, a content of 40% by mass or less is thought to further reduce the likelihood of blistering.

[0124] (nucleating agent) The nucleating agent can promote the crystallization of the polyamide resin (A), thereby further increasing the tensile strength and elastic modulus of the resin workpiece.

[0125] Examples of nucleating agents include metal salt compounds such as sodium 2,2-methylenebis(4,6-di-t-butylphenyl)phosphate, aluminum tris(pt-butylbenzoate), and stearates; sorbitol compounds such as bis(p-methylbenzylidene)sorbitol and bis(4-ethylbenzylidene)sorbitol; and inorganic substances such as talc, calcium carbonate, and hydrotalcite. Among these, talc is preferred from the viewpoint of further increasing the crystallinity of the resin member. These nucleating agents may be used alone or in combination of two or more.

[0126] Talc generally contains hydrous magnesium silicate (SiO2: 58-64%, MgO: 28-32%, Al2O3: 0.5-5%, Fe2O3: 0.3-5%) as its main component. The average particle size of the talc is not particularly limited, but is preferably 1-15 μm. When the average particle size of the talc is within the above range, the talc can be easily dispersed in the polyamide resin (A) without impairing the fluidity of the polyamide resin composition. From the same viewpoint, the average particle size of the talc is more preferably 1-7.5 μm. The average particle size of the talc can be measured by a laser diffraction method, for example, using a Shimadzu particle size distribution analyzer (SALD-2000A) manufactured by Shimadzu Corporation.

[0127] The content of the nucleating agent is preferably 0.10 parts by mass to 5.00 parts by mass, and more preferably 0.10 parts by mass to 3.00 parts by mass, relative to the total mass of the polyamide resin composition. When the content of the nucleating agent is within the above range, the crystallinity of the resin member is easily increased sufficiently, and sufficient mechanical strength is easily obtained.

[0128] (sliding material) The lubricant improves the injection flowability of the polyamide resin composition and improves the appearance of the resulting resin part. The lubricant can be a metal salt of a fatty acid such as a metal salt of an oxycarboxylic acid or a metal salt of a higher fatty acid.

[0129] The oxycarboxylic acid constituting the oxycarboxylic acid metal salt may be an aliphatic oxycarboxylic acid or an aromatic oxycarboxylic acid. Examples of the aliphatic oxycarboxylic acid include aliphatic oxycarboxylic acids having 10 to 30 carbon atoms, such as α-hydroxymyristic acid, α-hydroxypalmitic acid, α-hydroxystearic acid, α-hydroxyeicosanoic acid, α-hydroxydocosanoic acid, α-hydroxytetraeicosanoic acid, α-hydroxyhexaeicosanoic acid, α-hydroxyoctaeicosanoic acid, α-hydroxytriacontanoic acid, β-hydroxymyristic acid, 10-hydroxydecanoic acid, 15-hydroxypentadecanoic acid, 16-hydroxyhexadecanoic acid, 12-hydroxystearic acid, and ricinoleic acid. Examples of the aromatic oxycarboxylic acid include salicylic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, gallic acid, mandelic acid, and trovic acid.

[0130] Examples of the metal constituting the metal oxycarboxylic acid salt include alkali metals such as lithium, and alkaline earth metals such as magnesium, calcium and barium.

[0131] Of these, the metal oxycarboxylic acid salt is preferably a metal salt of 12-hydroxystearic acid, and more preferably magnesium 12-hydroxystearate and calcium 12-hydroxystearate.

[0132] Examples of the higher fatty acids constituting the higher fatty acid metal salts include higher fatty acids having 15 to 30 carbon atoms, such as stearic acid, oleic acid, behenic acid, behenic acid, and montanic acid.

[0133] Examples of metals constituting the above higher fatty acid metal salts include calcium, magnesium, barium, lithium, aluminum, zinc, sodium, and potassium.

[0134] Of these, the higher fatty acid metal salts are preferably calcium stearate, magnesium stearate, barium stearate, calcium behenate, sodium montanate, and calcium montanate.

[0135] The content of the lubricant is preferably 0.01% by mass to 1.30% by mass relative to the total mass of the polyamide resin composition. When the content of the lubricant is 0.01% by mass or more, the fluidity during molding tends to be improved, and the appearance of the obtained molded product tends to be improved. When the content of the lubricant is 1.30% by mass or less, gas due to decomposition of the lubricant is unlikely to be generated during molding, and the appearance of the product tends to be good.

[0136] (Anti-drip agent) Anti-drip agents are additives used to prevent resin droplets from forming during combustion tests of molded polyamide resin compositions (e.g., tests according to the UL94 standard (1991)). Examples of anti-drip agents include maleic acid-modified styrene-ethylene-butylene-styrene (SEBS) copolymers and fluororesins.

[0137] (Halogen scavenger) When a halogen-containing compound is used as the flame retardant, the halogen scavenger is preferably contained in the polyamide resin composition. The halogen scavenger can capture halide ions generated when a molded article of the polyamide resin composition containing the halogen-containing compound is burned, thereby suppressing the generation of harmful substances. Examples of halogen scavengers include hydrotalcite.

[0138] 2. Method for producing polyamide resin composition The method for producing a polyamide resin composition according to this embodiment includes a step of melt-kneading a polyamide resin (A) having a melting point of 280°C or higher as measured by differential scanning calorimetry (DSC), a halogen-based flame retardant (B), and a polyolefin copolymer (C), wherein the polyolefin copolymer (C) contains structural units derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms and structural units containing a glycidyl group, and the content of the polyolefin copolymer (C) is 0.2% by mass to 3.5% by mass relative to the content of the polyamide resin (A).

[0139] As the melt-kneading method, a known resin kneading method can be used, for example, a method of mixing using a Henschel mixer, V blender, ribbon blender, or tumbler blender, or a method of further melt-kneading using a single-screw extruder, multi-screw extruder, kneader, or Banbury mixer after mixing. The melting temperature during melt-kneading is preferably at least 10°C above the melting point (Tm) of the polyamide resin (A) and at most 30°C above the melting point (Tm) of the polyamide resin (A).

[0140] 3. Molded body The molded article according to this embodiment is obtained by molding the polyamide resin composition produced by the above-described production method. By using the above-described polyamide resin composition, reflow heat resistance can be improved.

[0141] The molded article can be produced using the polyamide resin composition by a conventional melt molding method, such as compression molding, injection molding, etc. For example, the polyamide resin composition according to the present embodiment can be introduced into an injection molding machine whose cylinder temperature is adjusted to a temperature equal to or higher than the melting point of the polyamide resin (A), for example, in the range of 280°C to 350°C, to be in a molten state, and then introduced into a mold having a predetermined shape, thereby producing a molded article.

[0142] The shape of the molded article according to this embodiment is not particularly limited, and may take various shapes depending on the application.

[0143] Examples of applications of the molded article according to this embodiment include vehicle structural parts, vehicle-mounted items, housings for electronic devices, housings for home appliances, structural parts, machine parts, various automobile parts, electronic device parts, medical devices, etc. As described above, since the reflow heat resistance of the molded article can be improved, among these applications, it can be particularly suitably used for electronic device parts. [Example]

[0144] The present invention will be described below with reference to examples, which should not be construed as limiting the scope of the present invention.

[0145] 1. Synthesis / preparation of materials 1-1. Synthesis of polyamide resin (A) <Polyamide resin PA-1 (6T66)> 2515 g (15.1 mol) of terephthalic acid, 2800 g (24.1 mol) of 1,6-diaminohexane, 1325 g (9.0 mol) of adipic acid, 5.7 g of sodium hypophosphite monohydrate, and 554 g of distilled water were placed in a 13.6 L autoclave and purged with nitrogen. Stirring was initiated at 190°C, and the internal temperature was raised to 250°C over 3 hours. At this time, the internal pressure of the autoclave was increased to 3.01 MPa. After the reaction was continued for 1 hour, the low-order condensate was discharged into the atmosphere through a spray nozzle installed at the bottom of the autoclave and extracted. The extracted low-order condensate was cooled to room temperature, pulverized in a pulverizer to a particle size of 1.5 mm or less, and dried at 110°C for 24 hours.

[0146] Next, this low-order condensate was placed in a tray-type solid-state polymerization reactor, and after nitrogen substitution, the temperature was raised to 220°C over approximately 1 hour and 30 minutes. The low-order condensate was then reacted for 1 hour and cooled to room temperature. Subsequently, polyamide (high condensate) was further melt-polymerized in a twin-screw extruder with a screw diameter of 30 mm and L / D = 36 at a barrel setting temperature of 330°C, a screw rotation speed of 200 rpm, and a resin feed rate of 6 kg / hour to obtain polyamide resin PA-1.

[0147] The resulting polyamide resin PA-1 had an intrinsic viscosity [η] of 0.8 dL / g, a melting point (Tm) of 320°C, a glass transition temperature (Tg) of 95°C, and a heat of fusion (ΔH) of 49 J / g. The composition of the resulting polyamide resin PA-1 was such that the content of terephthalic acid-derived units relative to the total moles of dicarboxylic acid-derived units was 62.5 mol%, the content of adipic acid-derived units was 37.5 mol%, and the content of 1,6-diaminohexane-derived units relative to the total moles of diamine-derived units was 100 mol%. The amount of terminal amino groups in the polyamide resin PA-1 was 113 mmol / kg, and the amount of terminal carboxyl groups was 52 mmol / kg.

[0148] 1-2. Halogen-based flame retardants (B) Brominated polystyrene (Albemarle, HP-3010, bromine content: 68% by mass, number average molecular weight (Mn): 3400, weight average molecular weight (Mw): 4000, Mw / Mn: 1.2)

[0149] 1-3. Polyolefin copolymer (C) Ethylene-glycidyl (meth)acrylate copolymer (SK Functional Polymer, LOTADER® AX8840) LOTADER AX8840 has 92% by mass of ethylene-derived structural units and 8% by mass of glycidyl (meth)acrylate-derived structural units, when the total structural units of the copolymer are taken as 100% by mass, a melting point (Tm) of 106°C, and a melt flow rate (MFR) of 5 g / 10 min. The molar amount of the structural units containing glycidyl groups in the polyolefin copolymer (C) was 16.9 mmol / kg.

[0150] 1-4.Other ingredients 1-4-1.Flame retardant synergists Sodium antimonate (SA-A, manufactured by Nippon Seiko Co., Ltd.) 1-4-2. Reinforcement material Glass fiber (ECS03-615, manufactured by Central Glass Co., Ltd., cross-sectional aspect ratio: 3.0)

[0151] 1-4-3. Nucleating agent Talc (Matsumura Sangyo Co., Ltd., High Filler #5000PJ, average particle size 4.5 μm)

[0152] 1-4-4. Lubricants Calcium montanate (Clariant Japan, Licomont CAV102)

[0153] 1-4-5. Anti-drip agent m-SEBS (maleated SEBS, manufactured by Asahi Chemicals Corporation, Tuftec M1913)

[0154] 1-4-6.Halogen scavengers Hydrotalcite (NAOX-33, manufactured by Toda Kogyo Co., Ltd.)

[0155] 2. Measurement The physical properties of each of the above resins were measured by the following methods.

[0156] <Polyamide resin melting point (Tm) and glass transition temperature (Tg)> The melting point (Tm) and glass transition temperature (Tg) of the polyamide resin were measured using a differential scanning calorimeter (DSC220C, manufactured by Seiko Instruments Inc.). Specifically, approximately 5 mg of polyamide resin was sealed in an aluminum pan for measurement and set in the differential scanning calorimeter. The polyamide resin was then heated from room temperature to 350°C at 10°C / min. To completely melt the resin, it was held at 350°C for 3 minutes and then cooled to 30°C at 10°C / min. After leaving it at 30°C for 5 minutes, it was heated a second time to 350°C at 10°C / min. The temperature (°C) of the endothermic peak during this second heating was taken as the melting point (Tm) of the polyamide resin, and the inflection point corresponding to the glass transition was taken as the glass transition temperature (Tg).

[0157] <Heat of fusion (ΔH)> The heat of fusion (ΔH) of the polyamide resin was determined from the area of ​​the exothermic peak of crystallization during the first temperature rise in accordance with JIS K 7122:2012.

[0158] <Intrinsic viscosity [η]> The intrinsic viscosity [η] of the polyamide resin was calculated by dissolving 0.5 g of the polyamide resin in 50 ml of a 96.5% sulfuric acid solution, measuring the flow time of the resulting solution at 25°C ± 0.05°C using an Ubbelohde viscometer, and then calculating the intrinsic viscosity [η] based on the formula: [η] = ηSP / (C(1 + 0.205ηSP)). [η]: Intrinsic viscosity (dl / g) ηSP: Specific viscosity C: Sample concentration (g / dl) t: Number of seconds for sample solution to flow down (seconds) t0: Number of seconds the blank sulfuric acid flows (seconds) ηSP=(t-t0) / t0

[0159] <Terminal carboxyl group amount> 30 mg of polyamide resin was dissolved in 0.5 mL of deuterated hexafluoroisopropanol (HFIP) to prepare a sample for NMR measurement. NMR measurement of the sample was performed using a nuclear magnetic resonance spectrometer (ECA-500, JEOL Ltd.). The molecular weight of the polymer was calculated from the peak area derived from hydrogen atoms of each component constituting the polyamide resin in the obtained spectrum. The amount of terminal carboxyl groups ([COOH], unit: mmol / kg) was calculated using the peak area derived from hydrogen atoms specific to the terminal carboxyl groups and the molecular weight obtained above.

[0160] <Amount of terminal amino groups> 1 g of polyamide resin was dissolved in 35 mL of phenol and mixed with 2 mL of methanol to prepare a sample solution. Using thymol blue as an indicator, the sample solution was titrated with 0.01 N hydrochloric acid solution using a potentiometric titrator (Metrohm) from blue to yellow, and the amount of terminal amino groups ([NH2], unit: mmol / kg) was measured.

[0161] <Molar Amount of Structural Units Containing Glycidyl Groups in Polyolefin Copolymer (C)> Measurement was performed in accordance with JIS K7236:2001. Specifically, polyolefin copolymer (C) was dissolved in chloroform, and acetic acid and tetraethylammonium bromide acetate solution were added and mixed to prepare a sample solution. Potentiometric titration was performed on this sample solution using a 0.1 mol / L perchloric acid acetic acid standard solution using a potentiometric titrator (manufactured by Metrohm). The hydrogen bromide produced by the reaction of perchloric acid and tetraethylammonium bromide reacted with all the glycidyl groups contained in the sample solution, and the point at which hydrogen bromide became excessive was detected, and the molar amount of glycidyl groups contained was calculated.

[0162] 3. Preparation of polyamide resin composition The above materials were mixed in a tumbler blender in the composition ratios (units: parts by mass) shown in Table 1, and melt-kneaded using a 30 mmφ vented twin-screw extruder at a cylinder temperature of 300 to 335°C. The actual temperature of the composition in the cylinder was 350°C due to the influence of shear heat. The kneaded material was then extruded into strands and cooled in a water bath. The strands were then taken up and cut using a pelletizer to obtain polyamide resin compositions of Examples 1 to 4 and Comparative Examples 1 and 2. Note that with the composition ratio of Comparative Example 3, the strands broke when taken up using the pelletizer, making it impossible to form them into pellets, and therefore the following evaluations could not be performed.

[0163] 4. Evaluation <Flexural strength and toughness> Test pieces measuring 64 mm in length, 6 mm in width, and 0.8 mm in thickness were prepared by injection molding. The molding machine used, as well as the cylinder temperature and mold temperature, are shown below. Molding machine: Tupearl TR40S3A (manufactured by Sodick Plastic Co., Ltd.) Molding machine cylinder temperature: Polyamide resin melting point + 10°C Mold temperature: 120℃ The prepared test specimens were left at 23°C in a nitrogen atmosphere for 24 hours. Then, a bending test was performed using a bending tester (NTESCO AB5) at 23°C and 50% relative humidity. The test conditions were a span of 26 mm and a bending speed of 5 mm / min. The bending strength and the energy required to break the test specimens (toughness) were measured from the bending test.

[0164] <Flow length> Each polyamide resin composition was injection molded under the following conditions using a bar flow mold having a width of 10 mm and a thickness of 0.5 mm, and the flow length (mm) of the resin in the mold was measured. Injection molding machine: Tupearl TR40S3A (manufactured by Sodick Plastic Co., Ltd.) Injection pressure setting: 2000 kg / cm 2 Molding machine cylinder temperature: Polyamide resin melting point + 10°C Mold temperature: 120℃

[0165] <Reflow heat resistance temperature> Each polyamide resin composition was injection molded under the following conditions to prepare a test piece having a length of 64 mm, a width of 6 mm and a thickness of 0.8 mm. Molding machine: Tupearl TR40S3A (manufactured by Sodick Plastic Co., Ltd.) Molding machine cylinder temperature: Polyamide resin melting point + 10°C Mold temperature: 120℃

[0166] The prepared test specimens were conditioned at a temperature of 40°C and a relative humidity of 95% for 96 hours. The conditioned test specimens were placed on a 1 mm-thick glass epoxy substrate. A temperature sensor was installed on this substrate. The glass epoxy substrate with the test specimen mounted thereon was set in an air reflow soldering machine (AIS-20-82-C, manufactured by Atec Techtron Co., Ltd.) and subjected to a reflow process according to the temperature profile shown in Figure 1. As shown in Figure 1, the temperature was raised to 230°C at a predetermined rate; then, the temperature was raised to a predetermined set temperature (a: 268°C, b: 265°C, c: 260°C, d: 255°C, and e: 235°C) over 20 seconds, and then lowered to 230°C. The maximum set temperature at which the test specimen did not melt and no blisters formed on the surface was determined, and this maximum set temperature was defined as the reflow heat resistance temperature.

[0167] <Flame retardancy> Each polyamide resin composition was injection molded under the following conditions to prepare 1 / 32 inch x 1 / 2 x 5 inch test pieces. Using the prepared test pieces, a vertical flame test was carried out in accordance with the UL94 standard (UL Test No. UL94 dated June 18, 1991) to evaluate flame retardancy. Molding machine: Tupearl TR40S3A (manufactured by Sodick Plastic Co., Ltd.) Molding machine cylinder temperature: Polyamide resin melting point + 10°C Mold temperature: 120℃

[0168] Table 1 shows the composition and evaluation results of each polyamide resin composition.

[0169] [Table 1]

[0170] Comparison of Examples 1 to 4 with Comparative Examples 1 to 3 reveals that molded articles obtained from polyamide resin compositions containing a halogen-based flame retardant (B) and a specific polyolefin copolymer (C), in which the content of the polyolefin copolymer (C) is 0.2 mass % to 3.5 mass % when the content of the polyamide resin (A) is taken as 100 mass %, have high reflow heat resistance. [Industrial Applicability]

[0171] The polyamide resin composition of the present invention can improve the reflow heat resistance of molded articles, and is therefore useful, for example, in the field of electronic components.

Claims

1. a polyamide resin (A) having a melting point of 280°C or higher as measured by a differential scanning calorimeter (DSC); a halogen-based flame retardant (B); a polyolefin copolymer (C); Including, The polyolefin copolymer (C) contains a structural unit derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms and a structural unit containing a glycidyl group, The content of the polyolefin copolymer (C) is 0.2% by mass to 3.5% by mass when the content of the polyamide resin (A) is 100% by mass. Polyamide resin composition.

2. the mass of the structural unit containing a glycidyl group is 5% by mass or more relative to 100% by mass of all structural units constituting the polyolefin copolymer (C); The polyamide resin composition according to claim 1.

3. The polyolefin copolymer (C) contains a structural unit derived from ethylene and a structural unit derived from glycidyl (meth)acrylate. The polyamide resin composition according to claim 1.

4. the polyolefin copolymer (C) is substantially free of structural units other than the structural units derived from ethylene or the structural units derived from glycidyl (meth)acrylate; The polyamide resin composition according to claim 3.

5. The polyolefin copolymer (C) has a melting point of 100°C or higher as measured by a differential scanning calorimeter (DSC). The polyamide resin composition according to claim 1.

6. the content of the polyolefin copolymer (C) is 0.10% by mass to 1.50% by mass when the total mass of the polyamide resin composition is 100% by mass; The polyamide resin composition according to claim 1.

7. The molar amount of the structural unit having a glycidyl group in the polyolefin copolymer (C) contained in the polyamide resin composition is expressed as a molecule, the ratio of the amount of terminal carboxy groups in the polyamide resin (A) to the amount of terminal amino groups in the polyamide resin (A) contained in the polyamide resin composition, when the total molar amount is taken as the denominator, is 1.0 / 1.0 to 10.0 / 1.0; The polyamide resin composition according to claim 1.

8. a polyamide resin (A) having a melting point of 280°C or higher as measured by a differential scanning calorimeter (DSC); a halogen-based flame retardant (B); a polyolefin copolymer (C); A method for producing a polyamide resin composition, comprising a step of melt-kneading the The polyolefin copolymer (C) contains a structural unit derived from ethylene or an α-olefin monomer having 3 to 8 carbon atoms and a structural unit containing a glycidyl group, The content of the polyolefin copolymer (C) is 0.2% by mass to 3.5% by mass when the content of the polyamide resin (A) is 100% by mass. A method for producing a polyamide resin composition.

9. A molded product obtained by molding the polyamide resin composition according to any one of claims 1 to 7. Molded body.

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