Resin composition, pellets, and molded article

Abstract

To provide a resin composition which exhibits a small dimensional change rate when absorbing water and has low thermal expansion, and to provide pellets and a molded article.SOLUTION: The resin composition contains: a polyamide resin (A) containing a C6-12 aliphatic dicarboxylic acid unit (a1) and a xylylenediamine unit (a2); an amorphous polyamide resin (B) having a glass transition temperature of 80-150°C; a polyphenylene ether resin (C); and an inorganic filler (D). The content ratio of the polyamide resin (A) is 45-65 pts.mass based on 100 pts.mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition, a pellet, and a molded article, and more particularly to a resin composition containing a polyamide resin as a main component. [Background technology]

[0002] Polyamide resins are widely used as various industrial materials due to their excellent processability, durability, heat resistance, mechanical properties, and the like. Aliphatic polyamide resins, such as polyamide 6 and polyamide 66, have long been used as such polyamide resins. Furthermore, aromatic polyamide resins, which use aromatic dicarboxylic acids and / or aromatic diamines as raw materials for the polyamide resin, are also becoming more widely used. Furthermore, in order to improve the mechanical strength of polyamide resins, inorganic fillers such as reinforcing fibers are blended into polyamide resins (Patent Document 1, etc.). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-067166 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with recent technological innovations, polyamide resin compositions containing inorganic fillers are also required to have a small rate of dimensional change upon water absorption and low thermal expansion. The present invention aims to solve these problems and to provide a resin composition, pellets, and molded articles that have a small dimensional change rate upon water absorption and low thermal expansion. [Means for solving the problem]

[0005] In view of the above problems, the present inventors have conducted research and found that the above problems can be solved by blending two or more specific polyamide resins, a polyphenylene ether resin, and an inorganic filler. Specifically, the above problems were solved by the following means. <1> a polyamide resin (A) containing an aliphatic dicarboxylic acid unit (a1) having 6 to 12 carbon atoms and a xylylenediamine unit (a2); an amorphous polyamide resin (B) having a glass transition temperature of 80 to 150°C; a polyphenylene ether resin (C); and an inorganic filler (D), A resin composition, wherein the content of polyamide resin (A) is 45 to 65 parts by mass based on 100 parts by mass of the total of polyamide resin (A) and amorphous polyamide resin (B). <2> the amorphous polyamide resin (B) is an amorphous polyamide resin containing 25 to 100 mol % of isophthalic acid units (b1), 0 to 75 mol % of dicarboxylic acid units (b2) having 6 to 12 carbon atoms other than isophthalic acid (provided that the total of (b1) and (b2) does not exceed 100 mol %), and diamine units (b3) having 4 to 10 carbon atoms; <1> The resin composition according to claim 1. <3> The polyamide resin (A) has a glass transition temperature of 60 to 90°C as measured by differential scanning calorimetry. <1> or <2> The resin composition according to claim 1. <4> The amorphous polyamide resin (B) has a glass transition temperature measured by differential scanning calorimetry of more than 90°C and not more than 140°C. <1> ~ <3> The resin composition according to any one of the above. <5> In the polyamide resin (A), the aliphatic dicarboxylic acid unit (a1) having 6 to 12 carbon atoms contains an α,ω-linear aliphatic dicarboxylic acid unit having 6 to 12 carbon atoms, and the xylylenediamine unit (a2) contains a paraxylylenediamine unit. <1> ~ <4> The resin composition according to any one of the above. <6> In the polyamide resin (A), the aliphatic dicarboxylic acid units (a1) having 6 to 12 carbon atoms contain sebacic acid units, and 80 mol % or more of the xylylenediamine units (a2) are paraxylylenediamine units. <1> ~ <5> The resin composition according to any one of the above. <7> In the polyamide resin (A), 90 mol % or more of the dicarboxylic acid units are sebacic acid units, and 90 mol % or more of the diamine units are paraxylylenediamine units. <1> ~ <6> The resin composition according to any one of the above. <8> In the amorphous polyamide resin (B), the dicarboxylic acid unit (b2) having 6 to 12 carbon atoms other than isophthalic acid contains an adipic acid unit and / or a terephthalic acid unit. <2> The resin composition according to claim 1. <9> the content of the polyphenylene ether resin (C) is 10 to 50 parts by mass per 100 parts by mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B); <1> ~ <8> The resin composition according to any one of the above. <10> The content of the inorganic filler (D) is 50 to 200 parts by mass per 100 parts by mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B). <1> ~ <9> The resin composition according to any one of the above. <11> the amorphous polyamide resin (B) is an amorphous polyamide resin containing 25 to 100 mol % of isophthalic acid units (b1), 0 to 75 mol % of dicarboxylic acid units (b2) having 6 to 12 carbon atoms other than isophthalic acid (provided that the total of (b1) and (b2) does not exceed 100 mol %), and diamine units (b3) having 4 to 10 carbon atoms; The polyamide resin (A) has a glass transition temperature of 60 to 90°C as measured by differential scanning calorimetry; the amorphous polyamide resin (B) has a glass transition temperature measured by differential scanning calorimetry of more than 90°C and not more than 140°C; In the polyamide resin (A), 90 mol % or more of the dicarboxylic acid units are sebacic acid units, and 90 mol % or more of the diamine units are p-xylylenediamine units, In the amorphous polyamide resin (B), the dicarboxylic acid unit (b2) having 6 to 12 carbon atoms other than isophthalic acid contains an adipic acid unit and / or a terephthalic acid unit, the content of the polyphenylene ether resin (C) is 10 to 50 parts by mass per 100 parts by mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B); The content of the inorganic filler (D) is 50 to 200 parts by mass per 100 parts by mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B). <1> ~ <10> The resin composition according to any one of the above. <12> <1> ~ <11> A pellet of the resin composition according to any one of the above. <13> <1> ~ <11> A molded article formed from the resin composition according to any one of the above items. <14> <12> A molded article formed from the pellets according to claim 1. [Effects of the Invention]

[0006] The present invention makes it possible to provide a resin composition, pellets, and molded articles that have a small rate of dimensional change upon water absorption and a low thermal expansion. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, an embodiment for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the present embodiment is an example for explaining the present invention, and the present invention is not limited to only this embodiment. In this specification, various physical properties and characteristic values ​​are those at 23°C unless otherwise specified. If the measurement methods, etc. described in the standards shown in this specification change from year to year, they will be based on the standards in effect as of January 1, 2024, unless otherwise specified. If the measurement methods, etc. described in the standards shown in this specification are abolished as of January 1, 2024, they will be based on the standards in effect at the time of abolition.

[0008] In this specification, unless otherwise specified, the melting point (Tm) and glass transition temperature (Tg) are values ​​measured by differential scanning calorimetry (DSC) in accordance with ISO 11357. Using a differential scanning calorimeter, a resin is placed in the measurement pan of the differential scanning calorimeter, heated to a temperature above the melting point at a rate of 10°C / min under a nitrogen atmosphere, and then rapidly cooled before measurement. The measurement conditions are a heating rate of 10°C / min, held at 350°C for 5 minutes, and then cooled to 30°C at a rate of -10°C / min, and the glass transition temperature (Tg) and melting point (Tm) are determined. The differential scanning calorimeter used is a "DSC-7020" manufactured by Hitachi High-Tech Science Corporation.

[0009] The resin composition of this embodiment is characterized by comprising a polyamide resin (A) containing an aliphatic dicarboxylic acid unit (a1) having 6 to 12 carbon atoms and a xylylenediamine unit (a2), an amorphous polyamide resin (B) having a glass transition temperature of 80 to 150°C, a polyphenylene ether resin (C), and an inorganic filler (D), and the content of the polyamide resin (A) is 45 to 65 parts by mass out of a total of 100 parts by mass of the polyamide resin (A) and the amorphous polyamide resin (B). By adopting such a constitution, it is possible to provide a resin composition that has a small rate of dimensional change when absorbing water and also has low thermal expansion.

[0010] The dimensional change of a polyamide resin composition when it absorbs water is generally caused by the polyamide resin having high water absorption properties. In this embodiment, a polyamide resin having high water absorption is blended with a polyamide resin (A) and an amorphous polyamide resin (B). When the amorphous polyamide resin (B) is miscible with the polyamide resin (A), the crystallinity of the polyamide resin (A) decreases. On the other hand, it is known that crystallization of polyamide resins progresses when the polyamide resin absorbs water. In this embodiment, the polyamide resin (A) and the amorphous polyamide resin (B) are blended in equal or nearly equal blend ratios. It is presumed that this configuration suppresses dimensional change of the resin composition as a whole when it absorbs water by canceling out the expansion that would normally occur due to water absorption with contraction caused by the progress of crystallization. In addition, the thermal expansion of a resin composition generally tends to increase when heated. However, the amorphous polyamide resin (B) has a relatively high glass transition temperature of 80 to 150°C for a polyamide resin. Therefore, expansion tends to be suppressed over a wide temperature range below the glass transition temperature of the amorphous polyamide resin (B). Furthermore, polyphenylene ether resins are resins that inherently have high glass transition temperatures. Under these circumstances, in this embodiment, it is presumed that by blending the amorphous polyamide resin (B) and the polyphenylene ether resin (C) with the polyamide resin (A), thermal expansion up to about 120°C can be effectively suppressed. From the above results, it is presumed that the resin composition of this embodiment has a small dimensional change rate upon water absorption and low thermal expansion. The dimensional change rate upon water absorption is suppressed in the flow direction (MD) of the resin composition of the molded article due to the addition of inorganic filler (D), and therefore the dimensional change rate upon water absorption tends to be smaller in MD than in the transverse direction (TD).

[0011] Hereinafter, the embodiments of the present invention will be described in detail. However, the explanation of the constituent elements described below is an example of an embodiment of the present invention, and the present invention is not limited to these contents.

[0012] <Polyamide resin (A)> The resin composition of the present embodiment contains a polyamide resin (A) containing an aliphatic dicarboxylic acid unit (a1) having 6 to 12 carbon atoms and a xylylenediamine unit (a2). By containing the polyamide resin (A), the water absorption rate of the resulting molded article can be reduced.

[0013] The aliphatic dicarboxylic acid unit (a1) having 6 to 12 carbon atoms preferably contains an α,ω-linear aliphatic dicarboxylic acid unit having 6 to 12 carbon atoms, more preferably contains an adipic acid unit and / or a sebacic acid unit, and even more preferably contains a sebacic acid unit. In the polyamide resin (A), it is preferred that preferably 75 mol % or more, more preferably 80 mol % or more, even more preferably 90 mol % or more, still more preferably 95 mol % or more, and particularly preferably 99 mol % or more of the dicarboxylic acid units are aliphatic dicarboxylic acid units (a1) having 6 to 12 carbon atoms (preferably sebacic acid).

[0014] The polyamide resin (A) may contain dicarboxylic acid units other than the aliphatic dicarboxylic acid units (a1) having 6 to 12 carbon atoms. Examples of dicarboxylic acid components constituting the other dicarboxylic acid units include phthalic acid compounds such as isophthalic acid, terephthalic acid, and orthophthalic acid, and isomers of naphthalenedicarboxylic acid such as 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid, and these can be used alone or in combination.

[0015] The xylylenediamine units (a2) may be either paraxylylenediamine units or metaxylylenediamine units, and preferably 80 mol % or more (preferably 90 mol % or more) are paraxylylenediamine units. More specifically, the xylylenediamine units (a2) preferably contain 0 to 80 mol% metaxylylenediamine units and 20 to 100 mol% paraxylylenediamine units (provided that the total of metaxylylenediamine units and paraxylylenediamine units does not exceed 100 mol%), more preferably contain 0 to 50 mol% metaxylylenediamine units and 50 to 100 mol% paraxylylenediamine units, even more preferably contain 0 to 30 mol% metaxylylenediamine units and 70 to 100 mol% paraxylylenediamine units, still more preferably contain 0 to 20 mol% metaxylylenediamine units and 80 to 100 mol% paraxylylenediamine units, and even more preferably contain 0 to 10 mol% metaxylylenediamine units and 90 to 100 mol% paraxylylenediamine units. The total of the paraxylylenediamine units and metaxylylenediamine units in the polyamide resin (A) preferably accounts for 80 mol% or more of the diamine units, more preferably 85 mol% or more, even more preferably 90 mol% or more, still more preferably 95 mol% or more, still more preferably 98 mol% or more, and still more preferably 99 mol% or more. The upper limit of the total of the paraxylylenediamine-derived structural units and metaxylylenediamine-derived structural units is 100 mol%.

[0016] The polyamide resin (A) may contain other diamine units in addition to the xylylenediamine unit (a2). Examples of the diamine components constituting the other diamine units include aliphatic diamines such as tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, and 2,4,4-trimethylhexamethylenediamine; 1,3-bis(aminomethyl)cyclohexane; 1,4-bis(aminomethyl)cyclohexane; Examples of the diamine include alicyclic diamines such as bis(4-aminophenyl)cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane, bis(aminomethyl)decalin, and bis(aminomethyl)tricyclodecane; and diamines having an aromatic ring such as bis(4-aminophenyl)ether, paraphenylenediamine, and bis(aminomethyl)naphthalene. These diamines may be used alone or in combination of two or more.

[0017] In the polyamide resin (A), it is preferred that the aliphatic dicarboxylic acid units (a1) having 6 to 12 carbon atoms contain α,ω-linear aliphatic dicarboxylic acid units having 6 to 12 carbon atoms, and the xylylenediamine units (a2) contain paraxylylenediamine units; it is more preferred that the aliphatic dicarboxylic acid units (a1) having 6 to 12 carbon atoms contain sebacic acid units, and 80 mol % or more of the xylylenediamine units (a2) are paraxylylenediamine units; and it is even more preferred that 90 mol % or more of the dicarboxylic acid units are sebacic acid units, and 90 mol % or more of the diamine units are paraxylylenediamine units.

[0018] The polyamide resin (A) used in this embodiment is primarily composed of diamine units and dicarboxylic acid units, but does not completely exclude other units. It goes without saying that the polyamide resin (A) may contain units derived from lactams such as ε-caprolactam and laurolactam, and aliphatic aminocarboxylic acids such as aminocaproic acid and aminoundecanoic acid. Here, "primary component" refers to the fact that, among the structural units constituting the polyamide resin (A), the total number of diamine units and dicarboxylic acid units is the largest among all units. In this embodiment, the total of the diamine units and dicarboxylic acid units in the polyamide resin (A) preferably accounts for 90% by mass or more of all units, more preferably 95% by mass or more, even more preferably 97% by mass or more, and even more preferably 99% by mass or more.

[0019] It is also preferable to use a polyamide resin (biomass polyamide resin) produced using a biomass raw material as the polyamide resin (A). The use of a biomass polyamide resin can reduce the environmental impact. For example, a biomass polyamide resin can be obtained by using a sebacic acid unit as the aliphatic dicarboxylic acid unit (a1) having 6 to 12 carbon atoms.

[0020] The polyamide resin (A) used in this embodiment may be a recycled polyamide resin product (including recovered products, material recycled products, chemical recycled products, etc.), a rejected product, or scrap material generated when molding a molded product from a resin composition.

[0021] The polyamide resin (A) may be a crystalline resin or an amorphous resin, but is preferably a crystalline resin. By crystalline resin is meant that it has a distinct melting point as measured by differential scanning calorimetry (DSC).

[0022] The glass transition temperature of the polyamide resin (A) is preferably 60°C or higher, more preferably 65°C or higher, and even more preferably 70°C or higher, and is preferably 90°C or lower, more preferably 85°C or lower, and even more preferably 80°C or lower. By setting the glass transition temperature at or above the lower limit, thermal expansion in the low temperature range below the glass transition temperature tends to be more effectively suppressed. On the other hand, by setting the glass transition temperature at or below the upper limit, shrinkage during processing tends to be smaller. When the resin composition of the present embodiment contains two or more types of polyamide resins (A), the glass transition temperatures of the polyamide resins (A) are weighted average values.

[0023] <Polyamide resin (B)> The resin composition of the present embodiment contains an amorphous polyamide resin (B) having a glass transition temperature of 80 to 150° C. By containing such an amorphous polyamide resin (B), the dimensional change rate upon water absorption can be reduced, and thermal expansion can be effectively suppressed. The polyamide resin (B) is preferably an amorphous polyamide resin containing 25 to 100 mol% of isophthalic acid units (b1), 0 to 75 mol% of dicarboxylic acid units (b2) having 6 to 12 carbon atoms other than isophthalic acid (provided that the sum of (b1) and (b2) does not exceed 100 mol%), and diamine units (b3) having 4 to 10 carbon atoms, and more preferably an amorphous polyamide resin containing 40 to 90 mol% of isophthalic acid units (b1), 10 to 60 mol% of dicarboxylic acid units (b2) having 6 to 12 carbon atoms other than isophthalic acid, and diamine units (b3) having 4 to 10 carbon atoms.

[0024] The dicarboxylic acid unit (b2) having 6 to 12 carbon atoms other than isophthalic acid is preferably an aliphatic dicarboxylic acid unit having 6 to 12 carbon atoms, an alicyclic dicarboxylic acid unit having 6 to 12 carbon atoms, or an aromatic dicarboxylic acid unit having 6 to 12 carbon atoms, and more preferably an α,ω-linear aliphatic dicarboxylic acid unit having 6 to 12 carbon atoms and / or an aromatic dicarboxylic acid unit having 6 to 12 carbon atoms. The aliphatic dicarboxylic acid unit having 6 to 12 carbon atoms more preferably contains an adipic acid unit and / or a sebacic acid unit, and even more preferably contains an adipic acid unit. The alicyclic dicarboxylic acid unit having 6 to 12 carbon atoms is preferably 1,3-bisaminomethylcyclohexane and / or 1,4-bisaminomethylcyclohexane. Examples of the aromatic dicarboxylic acid unit having 6 to 12 carbon atoms include a terephthalic acid unit and a phthalic acid compound unit such as orthophthalic acid unit, with the terephthalic acid unit being preferred.

[0025] In the polyamide resin (B), it is preferred that 25 mol % or more of the dicarboxylic acid units are isophthalic acid units (b1). In the polyamide resin (B), 75 mol % or less of the dicarboxylic acid units are preferably dicarboxylic acid units (b2) having 6 to 12 carbon atoms (preferably adipic acid units and / or terephthalic acid units, more preferably adipic acid units). In the polyamide resin (B), the sum of the isophthalic acid units (b1) and the dicarboxylic acid units (b2) having 6 to 12 carbon atoms preferably accounts for at least 75 mol%, more preferably at least 80 mol%, even more preferably at least 90 mol%, still more preferably at least 95 mol%, and particularly preferably at least 99 mol% of the dicarboxylic acid units. The sum of (b1) and (b2) does not exceed 100 mol%.

[0026] The polyamide resin (B) may contain dicarboxylic acid units other than the isophthalic acid (b1) and the dicarboxylic acid units (b2) having 6 to 12 carbon atoms.

[0027] The type of the diamine unit (b3) having 4 to 10 carbon atoms is not particularly limited, and it may be an aliphatic diamine, an alicyclic diamine, or an aromatic diamine, with an aliphatic diamine and / or an aromatic diamine being preferred. Examples of aliphatic diamines include tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, and nonamethylenediamine, with hexamethylenediamine being preferred. Examples of the alicyclic diamine include 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,3-diaminocyclohexane, and 1,4-diaminocyclohexane. An example of the aromatic diamine is xylylenediamine, and paraxylylenediamine and / or metaxylylenediamine are preferred, with metaxylylenediamine being more preferred.

[0028] A first example of polyamide resin (B) is 25 to 90 mol% of isophthalic acid units, 10 to 75 mol% of adipic acid units (however, the total of isophthalic acid units and adipic acid units does not exceed 100 mol%), 60 to 100 mol% of metaxylylenediamine units, and 0 to 40 mol% of paraxylylenediamine units (however, the total of metaxylylenediamine units and paraxylylenediamine units does not exceed 100 mol%). In the first example of polyamide resin (B), the total of isophthalic acid units and adipic acid units preferably accounts for 90 mol% or more of the diamine units, and the total of metaxylylenediamine units and paraxylylenediamine units preferably accounts for 90 mol% or more of the diamine units.

[0029] A second example of polyamide resin (B) is 40 to 90 mol% of isophthalic acid units, 10 to 60 mol% of terephthalic acid units (provided that the total of isophthalic acid units and terephthalic acid units does not exceed 100 mol%), 60 to 100 mol% of hexamethylenediamine units, and 0 to 40 mol% of other diamine units (provided that the total of hexamethylenediamine units and other diamine units does not exceed 100 mol%). In the second example of polyamide resin (B), the total of isophthalic acid units and terephthalic acid units preferably accounts for 90 mol% or more of the diamine units, and hexamethylenediamine units preferably account for 90 mol% or more of the diamine units.

[0030] The polyamide resin (B) used in this embodiment is primarily composed of diamine units and dicarboxylic acid units, but does not completely exclude other units. It goes without saying that the polyamide resin (B) may contain units derived from lactams such as ε-caprolactam and laurolactam, and aliphatic aminocarboxylic acids such as aminocaproic acid and aminoundecanoic acid. Here, "primary component" refers to the fact that, among the structural units constituting the polyamide resin (B), the total number of diamine units and dicarboxylic acid units is the largest among all units. In this embodiment, the total of the diamine units and dicarboxylic acid units in the polyamide resin (B) preferably accounts for 90% by mass or more of all units, more preferably 95% by mass or more, even more preferably 97% by mass or more, and even more preferably 99% by mass or more.

[0031] The polyamide resin (B) is an amorphous resin.

[0032] The glass transition temperature of the polyamide resin (B) is 80° C. or higher, preferably more than 90° C., and more preferably 100° C. or higher, and is 140° C. or lower, preferably 130° C. or lower. By making the glass transition temperature equal to or higher than the lower limit, thermal expansion tends to be effectively suppressed. When the resin composition of the present embodiment contains two or more types of polyamide resins (B), the glass transition temperatures of the polyamide resins (B) are weighted average values.

[0033] It is also preferable to use a polyamide resin (B) produced using a biomass raw material (biomass polyamide resin), which can reduce the environmental impact. For polyamide resin (B), bio-based adipic acid can be used as a biomass raw material. Mass balance certified (ISCC PLUS) adipic acid can also be used. Mass balance certification means that the amount of renewable or bio-based raw materials used at each factory or production facility and the amount of products produced or shipped are quantified, and the quality is guaranteed.

[0034] The polyamide resin (B) used in this embodiment may be a recycled polyamide resin product (including recovered products, material recycled products, chemical recycled products, etc.), a rejected product, or scrap material generated when molding a molded product from a resin composition.

[0035] <Polyphenylene ether resin (C)> The resin composition of the present embodiment contains a polyphenylene ether resin (C). The polyphenylene ether resin (C) is not particularly limited in terms of its type, but it preferably contains a polyphenylene ether resin consisting of a resin represented by formula (1) and / or an acid-modified product thereof (sometimes simply referred to as a "polyphenylene ether resin" in this specification), and more preferably contains a polyphenylene ether resin that is a resin represented by formula (1). [ka] (In formula (1), R 51 ~R 55 , and ,R 61 ~R 64 are each independently a hydrogen atom, a hydroxy group, or an alkyl group having 1 to 4 carbon atoms, and R 65 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n is the number of repeating structural units and is a number of 10 or more.

[0036] In formula (1), R 51 ~R 55 , and ,R 61 ~R 65 The alkyl group having 1 to 4 carbon atoms in may be either linear or branched, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. Among these, a methyl group, an ethyl group, an n-propyl group, or an isopropyl group is preferred, and a methyl group is more preferred.

[0037] In formula (1), R 51 , R 53 , R 61 , and ,R 63 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or a methyl group, and even more preferably a hydrogen atom. R 52 , R 54 , R 62 , and ,R 64 is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or a methyl group, and even more preferably a methyl group. R 65 is preferably a hydrogen atom.

[0038] In formula (1), n ​​is a number of 10 or more, more preferably 20 or more, and although there is no particular upper limit, it is 300 or less.

[0039] The polyphenylene ether resin is preferably poly(2,6-dimethyl-1,4-phenylene ether), which is a resin represented by formula (1-1). [ka] (wherein n is the same as above).

[0040] The acid-modified resin represented by formula (1) may be a resin obtained by modifying the resin represented by formula (1) with a carboxylic acid or a carboxylic acid derivative. As the carboxylic acid or carboxylic acid derivative, an unsaturated carboxylic acid and its derivative are preferred from the viewpoint of reactivity with the resin represented by formula (1). Examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, sorbic acid, mesaconic acid, angelic acid, etc. Examples of derivatives of unsaturated carboxylic acids include acid anhydrides, esters, amides, imides, and metal salts, with acid anhydrides being preferred. Among the above, the acid-modified resin represented by formula (1) is preferably a resin obtained by modifying the resin represented by formula (1) with maleic acid or a maleic acid derivative (maleic acid-modified resin represented by formula (1)) from the viewpoints of exhibiting high flame retardancy and availability.

[0041] Examples of the maleic acid modified resin represented by formula (1) include resins having a structure represented by formula (1-2) and / or formula (1-3). Formula (1-2) [ka] (In formula (1-2), R 51 ~R 55 , R 61 , R 63 , R 64 , R 65 and n each independently have the same meaning as in formula (1).

[0042] Formula (1-3) [ka] (In formula (1-3), R 51 ~R 55 , R 61 , R 63 , R 64 and n each independently have the same meaning as in formula (1).

[0043] The intrinsic viscosity of the polyphenylene ether resin (C) measured in chloroform at 30°C is preferably 0.20 to 0.60 dL / g, more preferably 0.30 to 0.50 dL / g, and even more preferably 0.30 to 0.45 dL / g, from the viewpoint of exhibiting high flame retardancy and improving moldability.

[0044] As the polyphenylene ether resin (C), commercially available products such as "PX100F" (poly(2,6-dimethyl-1,4-phenylene ether), Tg = 207°C, intrinsic viscosity at 30°C measured in chloroform = 0.37 dL / g) and "PX100L" (poly(2,6-dimethyl-1,4-phenylene ether), Tg = 210°C, intrinsic viscosity at 30°C measured in chloroform = 0.47 dL / g) manufactured by Polyxylenol Singapore Pte. Ltd. can also be used.

[0045] The glass transition temperature of the polyphenylene ether resin (C) is preferably 195°C or higher, more preferably 200°C or higher, and preferably 240°C or lower, more preferably 230°C or lower. By setting the glass transition temperature at or above the lower limit, thermal expansion can be more effectively suppressed. On the other hand, by setting the glass transition temperature at or below the upper limit, the fluidity and processability of the resin during processing tend to be further improved. When the resin composition of the present embodiment contains two or more types of polyphenylene ether resins (C), the glass transition temperatures of the polyphenylene ether resins (C) are weighted average values.

[0046] The polyphenylene ether resin (C) used in this embodiment may be a recycled product (including recovered products, material recycled products, chemical recycled products, etc.), a rejected product, or a waste material from molding a polyphenylene ether resin.

[0047] <Blend of polyamide resin (A), amorphous polyamide resin (B), and polyphenylene ether resin (C)> Next, the blend ratio of the polyamide resin (A), the amorphous polyamide resin (B), and the polyphenylene ether resin (C) in the resin composition of this embodiment will be described. In the resin composition of this embodiment, the content of polyamide resin (A) is 45 to 65 parts by mass out of a total of 100 parts by mass of polyamide resin (A) and amorphous polyamide resin (B). By making the content equal to or greater than the lower limit, dimensional change due to water absorption tends to be more effectively suppressed. On the other hand, by making the content equal to or less than the upper limit, the water absorption rate of the entire resin composition tends to be effectively suppressed and heat resistance tends to be more favorably maintained. Out of a total of 100 parts by mass of polyamide resin (A) and amorphous polyamide resin (B), the content of polyamide resin (A) is preferably 60 parts by mass or less, more preferably 55 parts by mass or less, and may even be 52 parts by mass or less.

[0048] In the resin composition of this embodiment, the content of the polyphenylene ether resin (C) is preferably 10 to 50 parts by mass per 100 parts by mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B). By making the content equal to or greater than the lower limit, thermal expansion tends to be more effectively suppressed. Meanwhile, by making the content equal to or less than the upper limit, the fluidity and processability of the resin during processing tend to be further improved. Furthermore, the mass proportion of the polyphenylene ether resin (C) relative to 100 parts by mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B) is preferably 25 parts by mass or more, more preferably 30 parts by mass or more, and even more preferably 35 parts by mass or more, and is preferably 45 parts by mass or less, and more preferably 40 parts by mass or less. The resin composition of the present embodiment may contain only one type of polyphenylene ether resin (C), or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0049] In the resin composition of the present embodiment, the total amount of the polyamide resin (A), the amorphous polyamide resin (B), and the polyphenylene ether resin (C) is preferably 40% by mass or more, more preferably 45% by mass or more, even more preferably 50% by mass or more, and may be 53% by mass or more, and is preferably 70% by mass or less, more preferably 65% ​​by mass or less, and may be 60% by mass or less, based on 100% by mass of the resin composition. The resin composition of the present embodiment may contain only one type of polyamide resin (A) and one type of amorphous polyamide resin (B), or may contain two or more types of either one. When two or more types are contained, the total amount is preferably in the above range.

[0050] <Inorganic filler (D)> The resin composition of the present embodiment contains an inorganic filler (D). By containing the inorganic filler (D), the mechanical strength of the resulting molded article can be improved.

[0051] The shape of the inorganic filler (D) in this embodiment can be exemplified by scale-like, needle-like, and fibrous shapes, and a fibrous inorganic filler (reinforcing fiber) is preferred. When the inorganic filler (D) of this embodiment is fibrous, its fiber length (cut length) is preferably 100 μm or more, more preferably 150 μm or more, even more preferably 200 μm or more, and even more preferably 250 μm or more, and is preferably 1000 μm or less, more preferably 700 μm or less, even more preferably 600 μm or less, even more preferably 500 μm or less, and even more preferably 400 μm or less. By setting it to be equal to or greater than the lower limit, mechanical properties tend to be improved. Meanwhile, by setting it to be equal to or less than the upper limit, fluidity during injection molding tends to be further improved. When the inorganic filler (D) is fibrous, its cross section may be circular or flat. When the inorganic filler (D) has a flat cross section, the flatness is preferably 2-6, and more preferably 3-5.

[0052] Examples of the inorganic filler (D) include glass, metal oxides, metal hydroxides, carbonates, and sulfates, with glass being preferred. The inorganic filler (D) is preferably carbon fiber or glass fiber, and more preferably contains glass fiber.

[0053] Next, the glass fiber preferably used in this embodiment will be described. The glass fiber is a fiber obtained by melt spinning commonly supplied glass such as E-glass, C-glass, D-glass, R-glass, A-glass, S-glass, and alkali-resistant glass, but is not particularly limited as long as it can be made into glass fiber. In this embodiment, it is preferable to include E-glass.

[0054] The glass fibers used in this embodiment are preferably surface-treated with a known silane coupling agent such as epoxy silane, amino silane, or vinyl silane, or with phosphoric acid. The amount of the surface treatment agent attached is preferably 0.01 to 1% by mass of the glass fibers. Furthermore, if necessary, the glass fibers may be surface-treated with a lubricant such as a fatty acid amide compound or silicone oil, an antistatic agent such as a quaternary ammonium salt, a resin capable of forming a film such as an epoxy resin or urethane resin, or a mixture of a resin capable of forming a film and a thermal oxidation inhibitor.

[0055] The content of the inorganic filler (D) in the resin composition of this embodiment is preferably 50 parts by mass or more, more preferably 60 parts by mass or more, even more preferably 70 parts by mass or more, even more preferably 80 parts by mass or more, even more preferably 90 parts by mass or more, even more preferably 95 parts by mass or more, and is preferably 200 parts by mass or less, more preferably 180 parts by mass or less, even more preferably 150 parts by mass or less, and even more preferably 100 parts by mass or less, relative to 100 parts by mass in total of the polyamide resin (A) and the amorphous polyamide resin (B).

[0056] In the resin composition of this embodiment, the content of inorganic filler (D) (preferably glass fiber) is preferably 25% by mass or more, more preferably 30% by mass or more, and even more preferably 35% by mass or more, and is preferably 55% by mass or less, more preferably 50% by mass or less, and even more preferably 45% by mass or less. The resin composition of the present embodiment may contain only one type of inorganic filler (D), or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0057] <Compatibilizer (E)> The resin composition of this embodiment preferably contains a compatibilizer (E). By containing the compatibilizer (E), the compatibility between the polyphenylene ether resin (C) and the polyamide resin (A) and the amorphous polyamide resin (B) can be improved. The compatibilizer (E) facilitates the formation of crosslinked structures between the polyphenylene ether resin (C) and the polyamide resin (A) and the amorphous polyamide resin (B), and can significantly increase the dispersibility of both resins. This is presumably responsible for improved impact resistance and mechanical strength stability.

[0058] The compatibilizer (E) is preferably an unsaturated carboxylic acid or anhydride thereof. Specific examples include fumaric acid, maleic anhydride, itaconic anhydride, chloromaleic anhydride, citraconic anhydride, butenyl succinic anhydride, tetrahydrophthalic anhydride, and the acids. These unsaturated carboxylic acid anhydrides and / or unsaturated carboxylic acids may be used alone or in combination. Among these, maleic anhydride and / or maleic acid are preferred, and maleic anhydride is most preferred. The compatibilizer (E) may also be a commercially available product; for example, Crystalman AB manufactured by NOF Corporation can be used.

[0059] The compatibilizer (E) may be compounded in the form of a masterbatch.

[0060] The content of the compatibilizer (E) in the resin composition of this embodiment is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, even more preferably 0.3 parts by mass or more, and even more preferably 0.5 parts by mass or more, per 100 parts by mass of the polyamide resin (A) and the amorphous polyamide resin (B) combined. By ensuring that the content is above the lower limit, compatibility with the polyphenylene ether (C) tends to be further improved. Furthermore, the upper limit of the content of the compatibilizer (E) is 10 parts by mass or less, preferably 5 parts by mass or less, more preferably 3 parts by mass or less, even more preferably 2 parts by mass or less, and even more preferably 1 part by mass or less, per 100 parts by mass of the polyamide resin (A) and the amorphous polyamide resin (B) combined. The resin composition of the present embodiment may contain only one type of compatibilizer (E), or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0061] <Impact modifier (F)> The resin composition of the present embodiment contains an impact resistance improver (F). By containing the impact resistance improver (F), a molded article having excellent impact resistance can be obtained. The impact resistance improver (F) is preferably a styrene-based elastomer. The styrene-based elastomer refers to an elastomer in which 10% by mass or more of the constituent units constituting the elastomer are constituent units derived from a vinyl aromatic hydrocarbon compound containing styrene, and preferably 20 to 50% by mass of the constituent units derived from a vinyl aromatic hydrocarbon.

[0062] The impact resistance improver (F) has a hard segment block derived from a vinyl aromatic hydrocarbon and a soft segment block having a rubber structure. The soft segment block is composed of a polymer block of a conjugated diene hydrocarbon compound, and has a glass transition temperature of typically 0°C or lower, preferably -20°C or lower, and more preferably -30°C or lower.

[0063] The impact modifier (F) is preferably a hydrogenated elastomer, and is a hydrogenated product of an ABA type block copolymer (where A represents a polymer block of a vinyl aromatic hydrocarbon compound, and B represents a polymer block of a conjugated diene hydrocarbon compound).

[0064] The vinyl aromatic hydrocarbon compound of A includes a vinyl allyl compound, and is preferably at least one selected from the group consisting of styrene, α-methylstyrene, styrene substituted with an alkoxy group, 2-vinylpyridine, 4-vinylpyridine, vinylnaphthalene, and vinylnaphthalene substituted with an alkyl group, more preferably styrene and α-methylstyrene, and even more preferably styrene. The vinyl aromatic compound may be one type or two or more types.

[0065] The content of the A block in the impact modifier (F) used in this embodiment is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 20% by mass or more, and even more preferably 25% by mass or more. By making the content equal to or greater than the lower limit, the impact resistance of the resulting molded article can be effectively improved without reducing heat resistance. Furthermore, the content of the A block in the impact modifier (F) is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less. By making the content equal to or less than the upper limit, the impact resistance and nominal tensile strain of the resulting molded article tend to be improved.

[0066] Examples of the conjugated diene hydrocarbon compound of B include isoprene and butadiene. The B block may be a random polymer of isoprene and butadiene. The total of the A block and the B block of the impact modifier (F) preferably accounts for 95% by mass or more of the total.

[0067] The impact modifier (F) used in this embodiment is preferably SEBS, which is represented by the following structural formula, where i, k, l, m, and n are each a number greater than 0. [ka]

[0068] The impact modifier (F) used in this embodiment is preferably a hydrogenated elastomer, but may be a partially hydrogenated product or a fully hydrogenated product, with a fully hydrogenated product being preferred. A fully hydrogenated product means a hydrogenation rate of 90%, preferably 95% or more, and more preferably 99% or more.

[0069] The impact resistance improver (F) may be compounded in the form of a masterbatch.

[0070] The content of the impact modifier (F) in the resin composition of this embodiment is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and even more preferably 5 parts by mass or more, per 100 parts by mass of the polyamide resin (A) and the amorphous polyamide resin (B) combined. By setting the content at or above the lower limit, impact resistance tends to be further improved. Furthermore, the upper limit of the content of the impact modifier (F) is preferably 15 parts by mass or less, more preferably 7 parts by mass or less, per 100 parts by mass of the polyamide resin (A) and the amorphous polyamide resin (B) combined.

[0071] The content of the impact resistance improver (F) is preferably 0.5% by mass or more, more preferably 1% by mass or more, and is preferably 5% by mass or less, more preferably 3% by mass or less, based on 100% by mass of the resin composition. The resin composition of the present embodiment may contain only one type of impact modifier (F), or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0072] <Stabilizer (G)> The resin composition of this embodiment preferably contains a stabilizer (G). The stabilizer may be a light stabilizer or a heat stabilizer. Examples of stabilizers include organic stabilizers such as phenolic antioxidants, amine antioxidants, phosphorus-based antioxidants, and sulfur-based antioxidants, and inorganic stabilizers such as copper compounds and alkali halides, with inorganic stabilizers being preferred, and copper compounds and alkali halides being more preferred. Examples of the copper compound used in this embodiment include copper halides (e.g., copper iodide, copper bromide, copper chloride) and copper acetate, and are preferably selected from among copper (I) iodide, copper (II) iodide, copper (I) bromide, copper (II) bromide, copper (I) acetate, copper (II) acetate, copper (I) chloride, and copper (II) chloride, more preferably copper iodide, copper acetate, and copper (I) chloride, and even more preferably copper iodide.

[0073] The alkali halide used in this embodiment refers to a halide of an alkali metal. As the alkali metal, potassium and sodium are preferred, and potassium is more preferred. Furthermore, as the halogen atom, iodine, bromine, and chlorine are preferred, and iodine is more preferred. Specific examples of the alkali halide used in this embodiment include potassium iodide, potassium bromide, potassium chloride, and sodium chloride, and potassium iodide is preferred.

[0074] It is also preferable to use a combination of a copper compound and an alkali halide. When a copper compound and an alkali halide are combined, the mixture is preferably a copper compound:alkali halide mixture in a mass ratio of 1:3 to 1:15, more preferably a mixture in a mass ratio of 1:4 to 1:8. When a copper compound and an alkali halide are combined, the disclosures in paragraphs 0046 to 0048 of JP-A No. 2013-513681 may also be taken into consideration, the contents of which are incorporated herein by reference.

[0075] The stabilizer (G) may be blended in the form of a masterbatch. The stabilizer (G) may also be blended in the form of a masterbatch together with the compatibilizer (E) and the impact resistance improver (F).

[0076] The proportion of the stabilizer (G) in the resin composition of this embodiment is preferably 0.01 mass% or more, more preferably 0.02 mass% or more, and is preferably 2 mass% or less, more preferably 1 mass% or less, even more preferably 0.5 mass% or less, and even more preferably 0.3 mass% or less. The proportion of the copper compound (preferably copper iodide) in the resin composition of this embodiment is preferably 0.01 mass% or more, more preferably 0.02 mass% or more, and is preferably 2 mass% or less, more preferably 1 mass% or less, even more preferably 0.5 mass% or less, and even more preferably 0.3 mass% or less. The resin composition of the present embodiment may contain only one type of stabilizer (G), or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0077] <Black pigment (H)> The resin composition of the present embodiment preferably contains a black pigment (H). The type of black pigment (H) is not particularly limited, but carbon black is preferred. The carbon black is not limited in type, raw material, or production method, and any of furnace black, channel black, acetylene black, ketjen black, etc. can be used. Of these, furnace black is preferred.

[0078] DBP oil absorption of carbon black (unit: cm 3 / 100g) is 40~300cm 3 The upper limit is preferably 300 cm / 100 g. 3 / 100g or less is preferable, and 200cm 3 More preferably, the lower limit is 40 cm / 100 g or less. 3 / 100g or more is preferable, 50cm 3 / 100g or more is preferable, 60cm 3 / 100g or more is more preferable, 70cm 3 By adjusting the DBP oil absorption amount (unit: cm) to within the above upper and lower limits, the appearance of the resulting molded article tends to be improved. 3 / 100g) can be measured in accordance with JIS K6217-4.

[0079] The nitrogen adsorption specific surface area of ​​carbon black (unit: m 2 / g) is 100 to 300m 2 The nitrogen adsorption specific surface area is measured in accordance with JIS K6217-2.

[0080] The number-average particle size (unit: nm) of the black pigment (H) is preferably 5 to 60 nm. The upper limit is preferably 60 nm or less, more preferably 40 nm or less, even more preferably 30 nm or less, and even more preferably 25 nm or less. The lower limit is preferably 8 nm or more, more preferably 10 nm or more, even more preferably 12 nm or more, and even more preferably 14 nm or more. By keeping the size within the above upper and lower limits, the appearance of the resulting molded article tends to be improved. The number-average particle size can be determined by obtaining a magnified image of an aggregate according to the procedure described in ASTM D3849 (Standard Test Method for Black Pigment (H) - Morphological Characterization by Electron Microscopy), measuring the particle sizes of 3,000 unit constituent particles from this aggregate image, and then arithmetically averaging the particle sizes.

[0081] The black pigment (H) is preferably blended as a masterbatch in advance with a thermoplastic resin (e.g., a polyamide resin) because this increases the dispersibility of the black pigment (H) and tends to improve the mechanical properties of the resulting molded article. When the black pigment (H) is made into a masterbatch, the proportion of the black pigment (H) in the masterbatch is preferably 20 to 40 mass %, and the proportion of the thermoplastic resin is preferably 60 to 80 mass %.

[0082] The content of the black pigment (H) in the resin composition of this embodiment is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and even more preferably 0.1 parts by mass or more, per 100 parts by mass of the polyamide resin (A) and the amorphous polyamide resin (B) combined, and is preferably 5 parts by mass or less, more preferably 4 parts by mass or less, and even more preferably 3 parts by mass or less. The resin composition of the present embodiment may contain only one type of black pigment (H), or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0083] <Other ingredients> The resin composition of the present embodiment may contain other components in addition to those described above. Examples of other components include other thermoplastic resins such as polyester resins and polyolefin resins, and resin additives.

[0084] Resin additives include flame retardants, flame retardant auxiliaries, ultraviolet absorbers, heat aging inhibitors, plasticizers (low molecular weight polyolefins, polyethylene glycol, fatty acid esters, etc.), antistatic agents, nucleating agents, flow improvers (for example, metal stearates such as calcium stearate, sodium stearate, and lithium stearate), various peroxides, spreading agents, ultraviolet absorbers, colorants other than black pigments (known inorganic pigments such as titanium oxide, titanium yellow, iron oxide pigments, ultramarine, cobalt, Examples of organic pigments include azo pigments such as azo lake pigments, benzimidazolone pigments, diarylide pigments, and condensed azo pigments; phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green; condensed polycyclic pigments such as isoindolinone pigments, quinophthalone pigments, quinacridone pigments, perylene pigments, anthraquinone pigments, perinone pigments, and dioxazine violet; and azine dyes. The total amount of these resin additives is preferably less than 10% by mass, more preferably less than 5% by mass, and even more preferably less than 3% by mass, based on 100% by mass of the resin composition, and may be less than 1% by mass. In addition, the resin composition of this embodiment can be blended with additives described in paragraphs 0047 to 0103 of WO 2021 / 241471 within the scope of the present invention, the contents of which are incorporated herein by reference.

[0085] In the resin composition of the present embodiment, the polyamide resin (A), the amorphous polyamide resin (B), the polyphenylene ether resin (C), and the inorganic filler (D), as well as the compatibilizer (E), the impact resistance improver (F), the stabilizer (G), and the black pigment (H), which are blended as needed, preferably account for 90% by mass or more of the resin composition, more preferably 95% by mass or more, even more preferably 97% by mass or more, and may even account for 99% by mass or more.

[0086] <Physical properties of resin composition> The resin composition of this embodiment preferably has a small dimensional change rate upon water absorption. Specifically, when a molded article measuring 10 mm in length, 10 mm in width, and 3 mm in thickness formed from the resin composition of this embodiment is allowed to stand at 85°C and a relative humidity of 85%, the dimensional change rate (absolute value) upon water absorption is preferably 0.06% or less in MD. The lower limit of the dimensional change rate (absolute value) upon water absorption in MD is preferably 0%. Furthermore, the dimensional change rate upon water absorption in TD is preferably 0.14% or less, more preferably 0.12% or less, and even more preferably 0.10% or less. The lower limit of the dimensional change rate (absolute value) upon water absorption in TD is preferably 0%. The dimensional change rate upon water absorption is measured according to the description in the examples below.

[0087] <Method of manufacturing resin composition> The method for producing the resin composition of this embodiment is not limited, and a wide variety of known methods for producing resin compositions can be used, including a method in which the polyamide resin (A), amorphous polyamide resin (B), polyphenylene ether resin (C), inorganic filler (D), and other components added as needed are premixed using a mixer such as a tumbler or Henschel mixer, and then melt-kneaded using a mixer such as a Banbury mixer, roll, Brabender, single-screw kneading extruder, twin-screw kneading extruder, or kneader. The melt-kneading temperature is not particularly limited, but is usually in the range of 240 to 320°C. An example of the resin composition is pellets.

[0088] <Molded products> The molded article of this embodiment is formed from the resin composition or pellets of this embodiment. In this embodiment, a molded article may be produced by pelletizing the resin composition and molding the resulting pellets by various molding methods. Alternatively, a molded article may be produced by directly molding a resin composition that has been melt-kneaded in a kneader, without going through pelletization. The resin composition (e.g., pellets) is molded into a molded article by various molding methods. The shape of the molded article is not particularly limited and can be appropriately selected depending on the use and purpose of the molded article, and examples thereof include flat, rod, cylindrical, ring, circular, elliptical, polygonal, irregular, hollow, frame, box, panel, button, etc.

[0089] The method for forming the molded article is not particularly limited, and conventionally known molding methods can be used, such as injection molding, injection compression molding, extrusion molding, profile extrusion, transfer molding, blow molding, gas-assisted blow molding, blow molding, extrusion blow molding, IMC (in-mold coating) molding, rotational molding, multilayer molding, two-color molding, insert molding, sandwich molding, foam molding, and pressure molding. The resin composition of this embodiment is particularly suitable for molded articles obtained by injection molding, injection compression molding, and extrusion molding, and is particularly suitable for molded articles (injection-molded articles) obtained by injection molding. However, it goes without saying that the resin composition of this embodiment is not limited to molded articles obtained by these methods.

[0090] <Application> The resin composition, pellets, and molded articles of this embodiment are widely used in applications where polyamide resins, particularly blends of polyamide resins and polyphenylene ether resins, are commonly used, such as automobile and other transportation vehicle parts, general machine parts, precision machine parts, electronic and electrical equipment parts, office automation equipment parts, building materials and housing-related parts, medical devices, leisure and sporting goods, play equipment, medical supplies, daily necessities such as food packaging films, defense and aerospace products, etc. [Example]

[0091] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

[0092] [Table 1]

[0093] <Synthesis Example 1> A 50-liter reactor equipped with a stirrer, partial condenser, condenser, thermometer, dropping device, nitrogen inlet tube, and strand die was charged with 8950 g (44.25 mol) of sebacic acid (Ito Oil Mills, product name: Sebacic Acid TA), 12.54 g (0.074 mol) of calcium hypophosphite, and 6.45 g (0.079 mol) of sodium acetate. After thoroughly replacing the atmosphere with nitrogen, the reactor was pressurized to 0.4 MPa with nitrogen and heated from 20°C to 190°C with stirring over 55 minutes until the sebacic acid was uniformly melted. Next, 5960 g (43.76 mol) of paraxylylenediamine (Mitsubishi Gas Chemical Company, Inc.) was added dropwise over 110 minutes with stirring. During this time, the temperature inside the reactor was continuously raised to 293°C. During the dropping step, the pressure was controlled at 0.42 MPa, and the generated water was removed from the system via a partial condenser and a cooler. The temperature of the partial condenser was controlled in the range of 145 to 147°C. After the dropwise addition of paraxylylenediamine was completed, the polycondensation reaction was continued for 20 minutes at a pressure of 0.42 MPa inside the reaction vessel. During this time, the temperature inside the reaction vessel was increased to 296°C. The pressure inside the reaction vessel was then reduced from 0.42 MPa to 0.12 MPa over 30 minutes. During this time, the temperature inside the reaction vessel increased to 298°C. The pressure was then reduced at a rate of 0.002 MPa / min to 0.08 MPa over 20 minutes, and the amount of components with a molecular weight of 1,000 or less was adjusted. The temperature inside the reaction vessel was 301°C when the pressure reduction was complete. The system was then pressurized with nitrogen, and the temperature inside the reactor was 301°C, the resin temperature was 301°C, and the polymer was removed in the form of strands from the strand die, cooled in 20°C cooling water, and pelletized to obtain approximately 13 kg of polyamide resin. The cooling time in the cooling water was 5 seconds, and the strand take-up speed was 100 m / min. The melting point was 290°C, and the number average molecular weight was 17,000.

[0094] <Synthesis Example 2> A 50-L jacketed reactor equipped with a stirrer, partial condenser, condenser, thermometer, dropping tank, and nitrogen gas inlet tube was charged with 7.5 kg of adipic acid, 8.5 kg of isophthalic acid, 9.3 g of sodium hypophosphite monohydrate, and 4.8 g of sodium acetate. The reactor was thoroughly purged with nitrogen and heated to 180°C under a small nitrogen stream until the adipic acid and isophthalic acid were homogeneously melted. Then, 13.9 kg of meta-xylylenediamine was added dropwise over 170 minutes while stirring. During this time, the internal temperature was continuously raised to 265°C. Water produced by polycondensation was removed from the system via the partial condenser and condenser. After the dropwise addition of meta-xylylenediamine, the internal temperature was further raised to 270°C. The reaction was continued for 10 minutes, after which the polymer was removed as strands from a nozzle at the bottom of the reactor, cooled with water, and pelletized to obtain the polymer. Furthermore, when an attempt was made to measure the melting point according to the description in paragraph 0036 of WO 2017 / 090556, it was found that the resin did not have a clear melting point and was an amorphous resin.

[0095] Example 1, Example 2, Comparative Examples 1 to 4 <Compound> The black pigment (H) was pre-mixed with a portion of the polyamide resin (A) obtained in Synthesis Example 1 above, and the mixture was fed to an extruder (Shibaura Machine Co., Ltd., TEM26SS) and melt-kneaded at 300°C to obtain a masterbatch. The carbon black content in the masterbatch was 30% by mass. Next, each component was weighed to obtain the composition shown in Table 2 below, and the components except for the glass fiber were blended together with the masterbatch in a tumbler. The blend was then charged into the base of a twin-screw extruder (Shibaura Machine Co., Ltd., TEM26SS). After melting, the glass fiber was side-fed to produce pellets. The temperature of the twin-screw extruder was set to 300°C. Each component in Table 2 is shown in parts by mass.

[0096] <Dimensional change rate due to water absorption> The pellets obtained by the above manufacturing method were dried at 120°C for 4 hours, and then injection-molded into a rectangular flat plate (hereinafter referred to as a flat plate piece) measuring 100 mm in length, 100 mm in width, and 3 mm in thickness using an injection molding machine (Shibaura Machine Co., Ltd., "EC75SX") under conditions of a cylinder temperature of 300°C, a mold temperature of 130°C, and a molding cycle of 50 seconds. The obtained flat molded specimens were left to stand at 85°C and a relative humidity of 85%, and the dimensions of the flat molded specimens in the resin flow direction (MD) and the transverse direction (TD) were measured every 24 hours. The test was stopped when the dimensional change reached saturation, and the percentage change in the initial dimensions was calculated as the dimensional change due to water absorption. The dimensional change due to water absorption was expressed in %.

[0097] <Linear expansion coefficient> The pellets obtained by the above manufacturing method were dried at 120°C for 4 hours, and then injection-molded into ISO test specimens (4 mm thick) using an injection molding machine (Shibaura Machine Co., Ltd., "EC75SX") under conditions of a cylinder temperature of 300°C, a mold temperature of 130°C, and a molding cycle of 50 seconds. The center of the ISO test piece obtained above was cut into a piece measuring 10 mm in length, 10 mm in width, and 4 mm in thickness to obtain a test piece, which was used to measure the linear expansion coefficient. The test pieces were prepared so that the resin flow direction (MD) and the perpendicular direction (TD) of the test pieces were the measurement targets, and measurements were carried out from -30°C to 120°C at a heating rate of 3°C / min, and the linear expansion coefficient was calculated from the slope of the change in dimensions relative to the change in temperature. The unit is 1 / °C.

[0098] <Water absorption rate> The obtained flat molded specimen was left to stand at 85°C and a relative humidity of 85%, and the mass of the flat molded specimen was measured every 24 hours. The test was terminated when the mass change reached saturation, and the mass change rate relative to the initial mass was calculated as the water absorption rate. The water absorption rate is expressed in %.

[0099] <Charpy impact strength> The ISO test piece obtained above was machined to remove the gripping portions at both ends and to form a notch in the center to prepare a notched Charpy impact test piece in accordance with ISO 179. The Charpy impact strength (notched) of the obtained notched Charpy impact test piece was measured at a temperature of 23°C in accordance with ISO 179 to evaluate impact resistance. The unit of Charpy impact strength is kJ / m 2 As shown.

[0100] <Breaking stress> The ISO test specimens obtained above were subjected to measurement of tensile breaking stress at a temperature of 23°C in accordance with ISO-527. The unit of the breaking stress is MPa.

[0101] [Table 2]

[0102] In Table 2 above, E-06 in the linear expansion coefficient is × 10 -6 That is, E-05 is x10 -5 For example, the linear expansion coefficient of the MD of Example 1 is 4.89 × 10 -6 is. As is clear from the above results, the resin compositions of the present invention had a small dimensional change rate upon water absorption and a small linear expansion coefficient (Examples 1 and 2). Furthermore, they also had a low water absorption rate, excellent impact resistance, and a large breaking stress. In contrast, the resin compositions of the comparative examples either had a large rate of dimensional change upon water absorption or a large coefficient of linear expansion (Comparative Examples 1 to 4).

[0103] Although the present invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various modifications can be made without departing from the spirit and scope of the invention.

Claims

1. a polyamide resin (A) containing an aliphatic dicarboxylic acid unit (a1) having 6 to 12 carbon atoms and a xylylenediamine unit (a2); an amorphous polyamide resin (B) having a glass transition temperature of 80 to 150°C; a polyphenylene ether resin (C); and an inorganic filler (D), A resin composition in which the content of polyamide resin (A) is 45 to 65 parts by mass per 100 parts by mass of the total of polyamide resin (A) and amorphous polyamide resin (B).

2. The resin composition according to claim 1, wherein the amorphous polyamide resin (B) is an amorphous polyamide resin containing 25 to 100 mol% of isophthalic acid units (b1), 0 to 75 mol% of dicarboxylic acid units (b2) having 6 to 12 carbon atoms other than isophthalic acid (provided that the sum of (b1) and (b2) does not exceed 100 mol%), and diamine units (b3) having 4 to 10 carbon atoms.

3. 3. The resin composition according to claim 1, wherein the polyamide resin (A) has a glass transition temperature of 60 to 90°C according to differential scanning calorimetry.

4. The resin composition according to claim 1 or 2, wherein the amorphous polyamide resin (B) has a glass transition temperature measured by differential scanning calorimetry of more than 90°C and not more than 140°C.

5. 3. The resin composition according to claim 1, wherein in the polyamide resin (A), the aliphatic dicarboxylic acid unit (a1) having 6 to 12 carbon atoms comprises an α,ω-linear aliphatic dicarboxylic acid unit having 6 to 12 carbon atoms, and the xylylenediamine unit (a2) comprises a p-xylylenediamine unit.

6. 3. The resin composition according to claim 1, wherein in the polyamide resin (A), the aliphatic dicarboxylic acid units (a1) having 6 to 12 carbon atoms contain sebacic acid units, and 80 mol% or more of the xylylenediamine units (a2) are p-xylylenediamine units.

7. 3. The resin composition according to claim 1, wherein in the polyamide resin (A), 90 mol % or more of the dicarboxylic acid units are sebacic acid units and 90 mol % or more of the diamine units are paraxylylenediamine units.

8. 3. The resin composition according to claim 2, wherein in the amorphous polyamide resin (B), the dicarboxylic acid unit (b2) having 6 to 12 carbon atoms other than isophthalic acid includes an adipic acid unit and / or a terephthalic acid unit.

9. The resin composition according to claim 1 or 2, wherein the content of the polyphenylene ether resin (C) is 10 to 50 parts by mass per 100 parts by mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B).

10. The resin composition according to claim 1 or 2, wherein the content of the inorganic filler (D) is 50 to 200 parts by mass per 100 parts by mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B).

11. the amorphous polyamide resin (B) is an amorphous polyamide resin containing 25 to 100 mol % of isophthalic acid units (b1), 0 to 75 mol % of dicarboxylic acid units (b2) having 6 to 12 carbon atoms other than isophthalic acid (provided that the sum of (b1) and (b2) does not exceed 100 mol %), and diamine units (b3) having 4 to 10 carbon atoms; The polyamide resin (A) has a glass transition temperature of 60 to 90°C as measured by differential scanning calorimetry; the amorphous polyamide resin (B) has a glass transition temperature measured by differential scanning calorimetry of more than 90°C and not more than 140°C; In the polyamide resin (A), 90 mol % or more of the dicarboxylic acid units are sebacic acid units, and 90 mol % or more of the diamine units are p-xylylenediamine units, In the amorphous polyamide resin (B), the dicarboxylic acid unit (b2) having 6 to 12 carbon atoms other than isophthalic acid contains an adipic acid unit and / or a terephthalic acid unit, the content of the polyphenylene ether resin (C) is 10 to 50 parts by mass per 100 parts by mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B); The resin composition according to claim 1, wherein the content of the inorganic filler (D) is 50 to 200 parts by mass per 100 parts by mass of the total of the polyamide resin (A) and the amorphous polyamide resin (B).

12. Pellets of the resin composition according to claim 1, 2 or 11.

13. A molded article formed from the resin composition according to claim 1, 2 or 11.

14. A molded article formed from the pellets of claim 12.

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