Polyamide composition, electrical component, and method for improving heat aging resistance, flowability, and ion migration resistance of electrical component

Abstract

To provide: a polyamide composition capable of obtaining an electric component which has excellent heat aging resistance and flowability and does not generate ion migration when being energized; an electric component using the polyamide composition; and a method for improving heat aging resistance, flowability and ion migration resistance of an electric component.SOLUTION: A polyamide composition comprises a polyamide, a polyethyleneimine and an aromatic amine. An electric component is obtained by molding the polyamide composition. A method for improving heat aging resistance, flowability and ion migration resistance of an electric component comprises molding a polyamide composition comprising a polyamide, a polyethyleneimine and an aromatic amine to obtain an electric component.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a polyamide composition, an electrical component, and a method for improving the heat aging resistance, flowability, and ion migration resistance of an electrical component. [Background technology]

[0002] BACKGROUND ART Polyamides have been widely used as materials for various parts in the fields of clothing, industrial materials, automobiles, electrical and electronic equipment, industrial applications, etc., due to their excellent moldability, mechanical properties, and chemical resistance.

[0003] In recent years, the use environment of polyamides has tended to become thermally and mechanically severe, and polyamides with improved strength and rigidity under high temperature use and little change in durability under use under severe environments are required. In addition, with the trend toward thinner wall thickness for the purpose of reducing the weight of automobile parts to improve fuel efficiency and the miniaturization and precision of electric and electronic parts, good flowability and good appearance are required.

[0004] In particular, a method of adding copper halide to polyamide to impart heat aging resistance to a molded article obtained by molding a polyamide composition (see, for example, Patent Document 1) and a method of adding nigrosine to polyamide to improve flowability (see, for example, Patent Document 2) are known. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6304481 [Patent Document 2] Patent No. 6274782 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the method of adding copper halide to polyamide as described in Patent Document 1 etc. has a problem that when the molded article is used in an electric or electronic part, it is likely to cause defects such as a decrease in insulation property and ion migration. Also, the method of adding nigrosine to polyamide as described in Patent Document 2 etc. is likely to cause defects due to the inclusion of halogen.

[0007] The present invention has been made in view of the above circumstances, and provides a polyamide composition from which electrical components can be obtained that are excellent in heat aging resistance and fluidity and that do not undergo ion migration when current is applied, an electrical component using the polyamide composition, and a method for improving the heat aging resistance, fluidity, and ion migration resistance of an electrical component. [Means for solving the problem]

[0008] That is, the present invention includes the following aspects. (1) A polyamide composition comprising a polyamide, a polyethyleneimine, and an aromatic amine. (2) The polyamide composition according to claim 1, which is substantially free of halogens. (3) The polyamide composition according to (1) or (2), which contains 0.20 parts by mass or more of the polyethyleneimine per 100.00 parts by mass of the polyamide. (4) The polyamide composition according to any one of (1) to (3), which contains 0.20 parts by mass or more of the aromatic amine per 100.00 parts by mass of the polyamide. (5) The polyamide composition according to any one of (1) to (4), further comprising an inorganic filler. (6) The polyamide composition according to any one of (1) to (5), which is used for electrical components. (7) An electrical component obtained by molding the polyamide composition according to any one of (1) to (6). (8) A method for improving the heat aging resistance, fluidity, and ion migration resistance of an electrical component, comprising: A method comprising molding a polyamide composition containing a polyamide, a polyethyleneimine, and an aromatic amine to obtain an electrical component. [Effects of the Invention]

[0009] The polyamide composition of the above aspect can provide a polyamide composition that has excellent heat aging resistance and fluidity and that can be used to obtain electrical components that do not undergo ion migration when energized. The electrical components of the above aspect are formed by molding the polyamide composition, and have excellent heat aging resistance and fluidity and do not undergo ion migration when energized. The method of the above aspect can improve the heat aging resistance, fluidity, and ion migration resistance of the electrical components, and can provide electrical components that do not undergo ion migration when energized. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. The following embodiments are merely examples for explaining the present invention, and are not intended to limit the present invention to the following content. The present invention can be implemented by modifying it as appropriate within the scope of its gist.

[0011] In this specification, the term "polyamide" refers to a polymer having an amide (-NHCO-) ​​bond in the main chain.

[0012] <Polyamide composition> The polyamide composition of the present embodiment contains (A) a polyamide, (B) a polyethyleneimine, and (C) an aromatic amine. Hereinafter, these components may be abbreviated as component (A), component (B), and component (C), respectively.

[0013] The polyamide composition of the present embodiment is preferably substantially free of halogens. That is, the polyamide composition of the present embodiment is preferably substantially free of copper halides, which have conventionally been added for the purpose of improving heat aging resistance. This prevents defects caused by the presence of halogens, specifically, reduced insulation properties and defects during current application, when the polyamide composition is used in electrical and electronic components such as electrical components. The term "substantially free of halogen" used herein means that the polyamide composition contains no halogen or only a trace amount of halogen that does not cause the above-mentioned defects. A specific halogen content is, for example, 10 ppm by mass or less, and preferably 5 ppm by mass or less, relative to the total mass of the polyamide composition.

[0014] The polyamide composition of the present embodiment has the above-described configuration, and thus can provide an electrical component that is excellent in heat aging resistance and flowability and does not undergo ion migration when energized. Hereinafter, the property of not causing ion migration when energized may be referred to as "ion migration resistance."

[0015] In this specification, the term "heat aging resistance" refers to the ability to retain practically sufficient mechanical properties when a molded article is left in an air atmosphere at a high temperature below the melting point for a long period of time while maintaining its shape, i.e., resistance to thermal oxidation.

[0016] Each of the constituent components of the polyamide composition of the present embodiment will be described in detail below.

[0017] <(A) Polyamide> Examples of (A) polyamides include, but are not limited to, (Aa) polyamides obtained by ring-opening polymerization of lactams, (Ab) polyamides obtained by self-condensation of ω-aminocarboxylic acids, (Ac) polyamides obtained by condensing diamines and dicarboxylic acids, and copolymers thereof. One type of polyamide may be used alone, or two or more types may be used in combination.

[0018] (Aa) Examples of lactams used in the production of polyamides include, but are not limited to, pivalolactam, pyrrolidone, caprolactam, caprylolactam, enantholactam, undecalactam, and dodecalactam (laurolactam).

[0019] (Ab) The ω-aminocarboxylic acid used in the production of polyamide includes, but is not limited to, ω-amino fatty acids, which are ring-opened compounds of the lactams described above with water. Specific examples of the ω-aminocarboxylic acid include 6-aminocaproic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid. Other examples of the ω-aminocarboxylic acid include para-aminomethylbenzoic acid. Furthermore, two or more kinds of the lactam or ω-aminocarboxylic acid may be used in combination and condensed.

[0020] (Ac) Diamines (monomers) used in the production of polyamides include, but are not limited to, linear aliphatic diamines, branched aliphatic diamines, alicyclic diamines, and aromatic diamines. Examples of linear aliphatic diamines include, but are not limited to, ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, and tridecamethylenediamine. Examples of branched aliphatic diamines include, but are not limited to, 2-methylpentamethylenediamine (also known as 2-methyl-1,5-diaminopentane), 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 2-methyloctamethylenediamine, and 2,4-dimethyloctamethylenediamine. Examples of alicyclic diamines include, but are not limited to, 1,4-cyclohexanediamine, 1,3-cyclohexanediamine, and 1,3-cyclopentanediamine. Examples of aromatic diamines include, but are not limited to, metaxylylenediamine, paraxylylenediamine, metaphenylenediamine, orthophenylenediamine, and paraphenylenediamine.

[0021] (Ac) The dicarboxylic acid (monomer) used in the production of polyamide is not limited to the following, but examples thereof include aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, and aromatic dicarboxylic acids. Examples of aliphatic dicarboxylic acids include, but are not limited to, malonic acid, dimethylmalonic acid, succinic acid, 2,2-dimethylsuccinic acid, 2,3-dimethylglutaric acid, 2,2-diethylsuccinic acid, 2,3-diethylglutaric acid, glutaric acid, 2,2-dimethylglutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, tetradecanedioic acid, hexadecanedioic acid, octadecanedioic acid, eicosane diacid, and diglycolic acid. Examples of alicyclic dicarboxylic acids include, but are not limited to, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,3-cyclopentanedicarboxylic acid. Examples of aromatic dicarboxylic acids include, but are not limited to, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, and 5-sodium sulfoisophthalic acid. The diamine and dicarboxylic acid as the monomers may be condensed either individually or in combination of two or more.

[0022] If necessary, the polyamide may further contain units derived from a trivalent or higher polycarboxylic acid such as trimellitic acid, trimesic acid, pyromellitic acid, etc. The trivalent or higher polycarboxylic acid may be used alone or in combination of two or more.

[0023] Specific examples of (A) polyamide include, but are not limited to, polyamide 4 (poly-α-pyrrolidone), polyamide 6 (polycaproamide), polyamide 11 (polyundecaneamide), polyamide 12 (polydodecanamide), polyamide 46 (polytetramethylene adipamide), polyamide 56 (polypentamethylene adipamide), polyamide 66 (polyhexamethylene adipamide), polyamide 610 (polyhexamethylene sebacamide), polyamide 612 (polyhexamethylene adipamide), polyamide 613 (polyhexamethylene sebacamide), polyamide 614 (polyhexamethylene adipamide), polyamide 615 (polyhexamethylene adipamide), polyamide 616 (polyhexamethylene adipamide), polyamide 617 (polyhexamethylene sebacamide), polyamide 618 (polyhexamethylene adipamide), polyamide 619 (polyhexamethylene sebacamide), polyamide 620 (polyhexamethylene adipamide), polyamide 621 (polyhexamethylene adipamide), polyamide 622 (polyhexamethylene adipamide), polyamide 623 (polyhexamethylene adipamide), polyamide 624 (polyhexamethylene adipamide), polyamide 625 (polyhexamethylene adipamide), polyamide 626 (polyhexamethylene adipamide), polyamide 627 (polyhexamethylene adipamide), polyamide 628 (polyhexamethylene adipamide), polyamide 629 (polyhexamethylene adipamide), polyamide 630 (polyhexamethylene adipamide), polyamide 631 (polyhexamethylene adipamide), polyamide 632 (polyhexamethylene adipamide), polyamide 633 (polyhexamethylene adipamide), polyamide 634 (polyhexamethylene adipamide), polyamide 635 (polyhexamethylene adipamide), polyamide 636 (polyhexamethylene adipamide), polyamide 63 Polyamide 116 (polyundecamethyleneadipamide), Polyamide TMHT (trimethylhexamethylene terephthalamide), Polyamide 6T (polyhexamethylene terephthalamide), Polyamide 2Me-5T (poly 2-methylpentamethylene terephthalamide), Polyamide 9T (polynonamethylene terephthalamide), 2Me-8T (poly 2-methyloctamethylene terephthalamide), Polyamide 6I (polyhexamethylene isophthalamide), Polyamide 6C (poly Polyamide 2Me-5C (Poly 2-methylpentamethylenecyclohexanedicarboxamide), Polyamide 9C (Polynonamethylenecyclohexanedicarboxamide), 2Me-8C (Poly 2-methyloctamethylenecyclohexanedicarboxamide), Polyamide PACM12 (Polybis(4-aminocyclohexyl)methanedodecamide), Polyamide dimethyl PACM12 (Polybis(3-methylaminocyclohexyl)methanedodecamide) Examples of suitable polyamides include polyamide MXD6 (polymetaxylylene adipamide), polyamide 10T (polydecamethylene terephthalamide), polyamide 11T (polyundecamethylene terephthalamide), polyamide 12T (polydodecamethylene terephthalamide), polyamide 10C (polydecamethylene cyclohexane dicarboxamide), polyamide 11C (polyundecamethylene cyclohexane dicarboxamide), and polyamide 12C (polydodecamethylene cyclohexane dicarboxamide). The above "Me" represents a methyl group.

[0024] Among these, the (A) polyamide is preferably at least one polyamide selected from the group consisting of polyamide 6 (polycaproamide), polyamide 46 (polytetramethylene adipamide), polyamide 66 (polyhexamethylene adipamide), polyamide 610, polyamide 612, polyamide 6T (polyhexamethylene terephthalamide), polyamide 9T (polynonamethylene terephthalamide), polyamide 6I (polyhexamethylene isophthalamide), polyamide MXD6 (polymetaxylylene adipamide), and copolymer polyamides containing any of these as constituent components. As the (A) polyamide, polyamide 66 is particularly preferred from the viewpoint of improving heat aging resistance.

[0025] The ends of the polyamide may be capped with a known end-capping agent. Such an end-capping agent can also be added as a molecular weight regulator when producing a polyamide from the above dicarboxylic acid, the above diamine, and, if necessary, at least one compound selected from the group consisting of the above lactam and the above aminocarboxylic acid.

[0026] Examples of end-capping agents include, but are not limited to, monocarboxylic acids, monoamines, acid anhydrides, monoisocyanates, monoacid halides, monoesters, monoalcohols, etc. Examples of acid anhydrides include, but are not limited to, phthalic anhydride, etc. These end-capping agents may be used alone or in combination of two or more. Among these, monocarboxylic acids or monoamines are preferred as the end-capping agent. By blocking the ends of the polyamide with an end-capping agent, the resulting polyamide composition tends to have better thermal stability.

[0027] The monocarboxylic acid usable as the end-capping agent may be any monocarboxylic acid that is reactive with amino groups that may be present at the terminals of the polyamide. Specific examples of the monocarboxylic acid include, but are not limited to, aliphatic monocarboxylic acids, alicyclic monocarboxylic acids, and aromatic monocarboxylic acids. Examples of aliphatic monocarboxylic acids include, but are not limited to, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutyric acid. Examples of alicyclic monocarboxylic acids include, but are not limited to, cyclohexanecarboxylic acid. Examples of aromatic monocarboxylic acids include, but are not limited to, benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, and phenylacetic acid. These monocarboxylic acids may be used alone or in combination of two or more.

[0028] The monoamine usable as the end-capping agent may be any monoamine that is reactive with carboxyl groups that may be present at the terminals of the polyamide, and specific examples of the monoamine include, but are not limited to, aliphatic monoamines, alicyclic monoamines, and aromatic monoamines. Examples of aliphatic amines include, but are not limited to, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, and dibutylamine. Examples of alicyclic amines include, but are not limited to, cyclohexylamine and dicyclohexylamine. Examples of aromatic amines include, but are not limited to, aniline, toluidine, diphenylamine, naphthylamine, and the like. These monoamines may be used alone or in combination of two or more.

[0029] Polyamide compositions containing polyamides end-capped with an end-capping agent tend to have better heat resistance, flowability, toughness, low water absorption, and rigidity.

[0030] The content of the (A) polyamide is preferably 50% by mass or more and 95% by mass or less, and more preferably 60% by mass or more and 75% by mass or less, based on the total mass of the polyamide composition. By ensuring that the content of (A) polyamide is within the above range, electrical components having superior heat aging resistance can be obtained.

[0031] <(B) Polyethyleneimine> The polyamide composition of the present embodiment contains (B) polyethyleneimine, and thus electrical components having improved heat aging resistance and flowability can be obtained.

[0032] Examples of (B) polyethyleneimine include, but are not limited to, homopolymers of ethyleneimine, copolymers of ethyleneimine and amines having at least two amino groups, amidated polymers obtained by reacting at least one selected from the group consisting of crosslinked polyethyleneimine, grafted polyethyleneimine, and polyethyleneimine with at least one selected from the group consisting of carboxylic acid, carboxylic acid ester, carboxylic acid anhydride, and carboxylic acid amide, alkoxylated polyethyleneimine, hydroxy group-containing polyethyleneimine, amphoteric polyethyleneimine, and lipophilic polyethyleneimine. These may be used alone or in combination of two or more.

[0033] Generally, the homopolymers of ethyleneimine are obtained by polymerization of ethyleneimine (aziridine) in aqueous or organic solution in the presence of an initiator, an acid or a Lewis acid. The ethyleneimine homopolymer obtained by such a method is generally a branched polymer containing primary, secondary, and tertiary amino groups in a molar ratio of primary amino groups:secondary amino groups:tertiary amino groups = approximately 30%:40%:30%. The distribution of amino groups is 13 It can be measured using C-NMR spectroscopy.

[0034] Comonomers for forming the copolymers of ethyleneimine include amines having at least two amino groups, as described above. Examples of the comonomer include, but are not limited to, alkylenediamines having 2 to 10 carbon atoms in the alkylene group, with ethylenediamine or propylenediamine being particularly preferred. In addition to the above, examples of the comonomer include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenetriamine, tripropylenetetramine, dihexamethylenetriamine, aminopropylethylenediamine, and bisaminopropylethylenediamine.

[0035] In addition to the above, (B) polyethyleneimine is preferably a crosslinkable polyethyleneimine obtained by reacting polyethyleneimine with a bifunctional or polyfunctional crosslinking agent having, as a functional group, at least one selected from the group consisting of a halogenhydrin, a glycidyl, an aziridine, an isocyanate unit, and a halogen atom. Examples include epichlorohydrin; bischlorohydrin ethers of polyalkylene glycols and 2 to 100 units selected from the group consisting of ethylene oxide units and propylene oxide units, and compounds described in German Patent Application Publication No. 19931720 and U.S. Pat. No. 4,144,123. As a method for producing crosslinkable polyethyleneimine, the methods described in the above-mentioned documents and European Patent Publication Nos. 895521 and 25515 can be applied.

[0036] Furthermore, (B) polyethyleneimine also includes grafted polyethyleneimine as a suitable example. As the grafting agent, any compound capable of reacting with the amino or imino group of polyethyleneimine can be used. As a method for producing the grafting agent and the grafted polyethyleneimine, for example, the method described in European Patent Publication No. 675914 can be applied.

[0037] Among these, (B) polyethyleneimine is preferably an amidated polymer obtained by reacting polyethyleneimine with any one selected from the group consisting of carboxylic acid, carboxylic acid ester, carboxylic acid anhydride, and carboxylic acid amide.

[0038] Depending on the proportion of amidated nitrogen atoms in the polyethyleneimine chain, the amidated polymer can be subsequently crosslinked with a predetermined crosslinking agent. In this case, up to 30 mol% of the amino functional groups are amidated so that at least one atom selected from the group consisting of primary nitrogen atoms and secondary nitrogen atoms can still be sufficiently supplied for the subsequent crosslinking reaction. That is, to ensure that at least one atom selected from the group consisting of primary nitrogen atoms and secondary nitrogen atoms is present in the amidated polymer, it is preferred that the amino functional groups in the amidated polymer are amidated at a proportion of 30 mol% or less. The carboxylic acids are all consumed by the amidation, and the amidated polymer has no carboxylic acid terminal groups, so it can be clearly distinguished from organic acids.

[0039] Furthermore, as the (B) polyethyleneimine, for example, an alkoxylated polyethyleneimine obtained by reacting polyethyleneimine with at least one selected from the group consisting of ethylene oxide and propylene oxide is also preferred.Similar to the above-mentioned amidated polymer, such an alkoxylated polymer is also preferred in that it can be crosslinked later with a predetermined crosslinking agent.

[0040] Furthermore, as (B) polyethyleneimine, from the viewpoint of affinity with polyamide resins, hydroxy group-containing polyethyleneimine and amphoteric polyethyleneimine (incorporation of anionic groups), and generally lipophilic polyethyleneimine obtained by incorporating long-chain hydrocarbon groups into the polymer chain, are also preferred. Methods for producing such polyethyleneimine polymers are known to those skilled in the art of the present invention.

[0041] The weight average molecular weight of (B) polyethyleneimine is preferably 100 or more and 3,000,000 or less, and more preferably 500 or more and 2,000,000 or less. When the weight-average molecular weight of (B) polyethyleneimine is equal to or greater than the above lower limit, the heat aging resistance can be improved, whereas when the weight-average molecular weight of (B) polyethyleneimine is equal to or less than the above upper limit, the mechanical properties of the electrical component, such as tensile strength, can be improved. The weight average molecular weight of (B) polyethyleneimine can be measured by a light scattering method.

[0042] The content of (B) polyethyleneimine in the polyamide composition of this embodiment is preferably 0.20 parts by mass or more, more preferably 0.30 parts by mass or more, even more preferably 0.50 parts by mass or more, and particularly preferably 0.70 parts by mass or more, per 100.00 parts by mass of (A) polyamide. When the content of (B) polyethyleneimine is equal to or more than the above lower limit, electrical components having more excellent heat aging resistance and flowability can be obtained. On the other hand, the content of (B) polyethyleneimine in the polyamide composition of this embodiment is preferably 5.00 parts by mass or less, more preferably 4.50 parts by mass or less, even more preferably 4.00 parts by mass or less, and particularly preferably 3.00 parts by mass or less, per 100.00 parts by mass of (A) polyamide. By having the content of (B) polyethyleneimine be equal to or less than the above upper limit, the mechanical properties of the electrical component, such as tensile strength, can be made better.

[0043] <(C) Aromatic amine> The polyamide composition of the present embodiment contains the aromatic amine (C), and thus electrical components having improved heat aging resistance and flowability can be obtained.

[0044] (C) Aromatic amine means an amine compound containing two carbon radicals chemically bonded to a nitrogen atom, wherein at least one, and preferably both, carbon radicals are aromatic.

[0045] (C) Aromatic amines preferably include, but are not limited to, at least one aromatic radical, such as a phenyl, naphthyl, or heteroaromatic group, substituted with at least one substituent containing from 1 to about 20 carbon atoms.

[0046] More specific examples of (C) aromatic amines include 4,4'-bis(α,α-dimethylbenzyl)diphenylamine, aromatic secondary amine compound condensation products which are reaction products of diphenylamine and acetone, p-(p-toluenesulfonylamido)diphenylamine, N,N'-di-(2-naphthyl)-p-phenylenediamine, 4,4'-bis(α,α'-t-octyl)diphenylamine, 4,4'-bis(α-methylbenzhydryl)diphenylamine, N-phenyl-1-naphthylamine, N,N'-diphenyl-p-phenylenediamine, N-naphthyl-N'-isopropyl-p-phenylenediamine, N-naphthyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine, etc. These may be used alone or in combination of two or more.

[0047] The content of the aromatic amine (C) in the polyamide composition of this embodiment is preferably 0.20 parts by mass or more, more preferably 0.30 parts by mass or more, even more preferably 0.50 parts by mass or more, and particularly preferably 0.70 parts by mass or more, per 100.00 parts by mass of the polyamide (A). When the content of the aromatic amine (C) is equal to or more than the above lower limit, electrical components having more excellent heat aging resistance and flowability can be obtained. On the other hand, the content of (C) aromatic amine in the polyamide composition of this embodiment is preferably 5.00 parts by mass or less, more preferably 4.00 parts by mass or less, even more preferably 3.00 parts by mass or less, and particularly preferably 2.00 parts by mass or less, per 100.00 parts by mass of (A) polyamide. By keeping the content of (C) aromatic amine at or below the above upper limit, the mechanical properties of the electrical component, such as tensile strength, can be made better.

[0048] <(D) Colorant> The polyamide composition may further contain (D) a colorant in addition to the above components (A) to (C).

[0049] As the (D) colorant, any colorant other than those containing halogen atoms such as nigrosine and metals such as aluminum, nickel, tin, copper, gold, silver, platinum, iron oxide, stainless steel, and titanium can be preferably used. Specific examples of the (D) colorant include pigments such as carbon black. The colorants may be used alone or in combination.

[0050] The content of the colorant in the polyamide composition of this embodiment is preferably 0.0001 parts by mass or more and 1.00 parts by mass or less, more preferably 0.001 parts by mass or more and 0.50 parts by mass or less, and even more preferably 0.001 parts by mass or more and 0.30 parts by mass or less, relative to 100.00 parts by mass of the (A) polyamide.

[0051] <(E) Inorganic filler> The polyamide composition preferably further contains (E) an inorganic filler in addition to the above components (A) to (C).

[0052] As the (E) inorganic filler, any filler other than those containing metals can be preferably used.

[0053] Specific examples of the (E) inorganic filler include, but are not limited to, carbon fiber, glass fiber, calcium silicate fiber, potassium titanate fiber, wollastonite, carbon nanotubes, etc. Among these, carbon fiber or glass fiber is preferred, and glass fiber is preferred from the viewpoint of increasing the strength of the polyamide composition, and carbon fiber is preferred from the viewpoint of improving the sliding properties. As the carbon fiber, for example, either polyacrylonitrile (PAN)-based carbon fiber or pitch-based carbon fiber can be used, with PAN-based carbon fiber being preferred from the viewpoint of mechanical properties. The above-mentioned inorganic fillers may be used alone or in combination of two or more kinds.

[0054] From the viewpoint of productivity, it is preferable to add short carbon fibers of about 3 mm to 10 mm by melt kneading in an extruder. In this case, it is preferable to add the carbon fibers from a side feeder from the viewpoint of preventing breakage of the carbon fibers.

[0055] From the viewpoint of affinity with polyamide resin, the carbon fiber is preferably coated with a urethane-based sizing agent, a maleic anhydride-based sizing agent, an acrylic-based sizing agent, or a polyamide-based sizing agent. From the viewpoint of physical properties and sliding properties, the carbon fiber preferably has a diameter of 5 μm or more and 10 μm or less.

[0056] The content of the inorganic filler in the polyamide composition of this embodiment is preferably 1 part by mass or more and 200 parts by mass or less, more preferably 5 parts by mass or more and 150 parts by mass or less, and even more preferably 15 parts by mass or more and 150 parts by mass or less, per 100 parts by mass of the (A) polyamide. By setting the content of the inorganic filler to be equal to or greater than the lower limit, the mechanical properties of the electrical component, such as tensile strength, can be improved, whereas by setting the content of the inorganic filler to be equal to or less than the upper limit, the flowability can be improved.

[0057] <(F) Other Ingredients> In addition to the above components (A) to (C), the polyamide composition may further contain (F) other components, as needed, within a range that does not impair the effects achieved by the polyamide composition of the present embodiment.

[0058] (F) Other components include (F1) lubricants, (F2) heat stabilizers, (F3) other resins, and the like.

[0059] ((F1) Lubricant) The lubricant (F1) is not particularly limited, but examples thereof include higher fatty acids, higher fatty acid metal salts, higher fatty acid esters, and higher fatty acid amides.

[0060] Examples of higher fatty acids include linear or branched, saturated or unsaturated aliphatic monocarboxylic acids having 8 to 40 carbon atoms. Examples of the linear or branched, saturated or unsaturated aliphatic monocarboxylic acids having from 8 to 40 carbon atoms include lauric acid, palmitic acid, stearic acid, behenic acid, and montanic acid. Examples of branched saturated aliphatic monocarboxylic acids having 8 to 40 carbon atoms include isopalmitic acid and isostearic acid. Examples of the linear unsaturated aliphatic monocarboxylic acid having from 8 to 40 carbon atoms include oleic acid and erucic acid. Examples of branched unsaturated aliphatic monocarboxylic acids having 8 to 40 carbon atoms include isooleic acid. These higher fatty acids may be used singly or in combination of two or more. Among these, stearic acid or montanic acid is preferred as the higher fatty acid.

[0061] The higher fatty acid metal salt is a metal salt of a higher fatty acid. Examples of the metal element of the metal salt include Group 1 elements, Group 2 elements, and Group 3 elements of the periodic table, zinc, aluminum, and the like. Examples of Group 1 elements in the periodic table include sodium and potassium. Examples of Group 2 elements in the periodic table include calcium and magnesium. Examples of Group 3 elements in the periodic table include scandium and yttrium. Among these, the metal elements are preferably elements of Groups 1 and 2 of the periodic table of the elements or aluminum, and more preferably sodium, potassium, calcium, magnesium or aluminum.

[0062] Specific examples of higher fatty acid metal salts include calcium stearate, aluminum stearate, zinc stearate, magnesium stearate, calcium montanate, sodium montanate, and calcium palmitate. These higher fatty acid metal salts may be used singly or in combination of two or more. Among these, metal salts of higher fatty acids are preferably metal salts of montanic acid or metal salts of stearic acid.

[0063] The higher fatty acid ester is an ester of a higher fatty acid and an alcohol. The higher fatty acid ester is preferably an ester of an aliphatic carboxylic acid having 8 to 40 carbon atoms and an aliphatic alcohol having 8 to 40 carbon atoms. Examples of the aliphatic alcohol having 8 to 40 carbon atoms include stearyl alcohol, behenyl alcohol, and lauryl alcohol. Specific examples of higher fatty acid esters include stearyl stearate and behenyl behenate. These higher fatty acid esters may be used singly or in combination of two or more.

[0064] Higher fatty acid amides are amide compounds of higher fatty acids. Examples of higher fatty acid amides include stearic acid amide, oleic acid amide, erucic acid amide, ethylene bisstearylamide, ethylene bisoleylamide, N-stearylstearic acid amide, and N-stearylerucic acid amide. These higher fatty acid amides may be used singly or in combination of two or more.

[0065] The content of the lubricant in the polyamide composition is preferably 0.001 to 1 part by mass, more preferably 0.03 to 0.5 parts by mass, per 100 parts by mass of the (A) polyamide in the polyamide composition. By setting the lubricant content within the above range, a polyamide composition having superior mold releasability, plasticization time stability, and toughness can be obtained, and an extreme decrease in molecular weight of the polyamide due to molecular chain scission can be more effectively prevented.

[0066] ((F2) Heat stabilizer) (F2) Heat stabilizers include, but are not limited to, phenol-based heat stabilizers, phosphorus-based heat stabilizers, amine-based heat stabilizers, and the like.

[0067] Examples of phenol-based heat stabilizers include, but are not limited to, hindered phenol compounds, etc. Hindered phenol compounds have the property of imparting excellent heat resistance and light resistance to resins such as polyamides and fibers.

[0068] Examples of the hindered phenol compound include, but are not limited to, N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-butyl-4-hydroxyphenylpropionamide)], pentaerythrityl-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], N,N'-hexamethylenebis(3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide), triethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate], onate], 3,9-bis{2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propynyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5,5]undecane, 3,5-di-tert-butyl-4-hydroxybenzylphosphonate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanuric acid, and the like. These hindered phenol compounds may be used alone or in combination of two or more. In particular, from the viewpoint of improving heat aging resistance, N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-butyl-4-hydroxyphenylpropionamide)] is preferred as the hindered phenol compound.

[0069] When a phenolic heat stabilizer is used, the content of the phenolic heat stabilizer in the polyamide composition is preferably 0.01% by mass or more and 1% by mass or less, more preferably 0.1% by mass or more and 1% by mass or less, relative to the total mass of the polyamide composition. When the content of the phenolic heat stabilizer is within the above range, the heat aging resistance of the polyamide composition can be further improved, and the amount of gas generation can be further reduced.

[0070] Examples of phosphorus-based heat stabilizers include, but are not limited to, pentaerythritol-type phosphite compounds, trioctyl phosphite, trilauryl phosphite, tridecyl phosphite, octyl diphenyl phosphite, trisisodecyl phosphite, phenyl diisodecyl phosphite, phenyl di(tridecyl) phosphite, diphenyl isooctyl phosphite, diphenyl isodecyl phosphite, diphenyl (tridecyl) phosphite, triphenyl phosphite, tris(nonyl) phosphite, tris(2,4-di-tert-butylphenyl)phosphite, tris(2,4-di-tert-butyl-5-methylphenyl)phosphite, tris(butoxyethyl)phosphite, 4,4'-butylidene-bis(3-methyl-6-tert-butylphenyl-tetra-tridecyl)diphosphite, tetra(C12-C15 mixed alkyl)-4,4'-isopropylidenediphenyldiphosphite, 4,4'-isopropylidenebis(2-tert-butylphenyl)-di(no tris(biphenyl)phosphite, tetra(tridecyl)-1,1,3-tris(2-methyl-5-tert-butyl-4-hydroxyphenyl)butane diphosphite, tetra(tridecyl)-4,4'-butylidenebis(3-methyl-6-tert-butylphenyl)diphosphite, tetra(C1-C15 mixed alkyl)-4,4'-isopropylidenediphenyl diphosphite, tris(mono- and di-mixed nonylphenyl)phosphite, 4,4'-isopropylidenebis(2 -tert-butylphenyl)-di(nonylphenyl)phosphite, 9,10-di-hydro-9-oxa-9-oxa-10-phosphaphenanthrene-10-oxide, tris(3,5-di-tert-butyl-4-hydroxyphenyl)phosphite, hydrogenated-4,4'-isopropylidenediphenyl polyphosphite, bis(octylphenyl)-bis(4,4'-butylidenebis(3-methyl-6-tert-butylphenyl))-1,6-hexanol diphosphite, hexatridecyl-1,1,Examples of such phosphite include 3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)diphosphite, tris(4,4'-isopropylidenebis(2-tert-butylphenyl))phosphite, tris(1,3-stearoyloxyisopropyl)phosphite, 2,2-methylenebis(4,6-di-tert-butylphenyl)octylphosphite, 2,2-methylenebis(3-methyl-4,6-di-tert-butylphenyl)2-ethylhexylphosphite, tetrakis(2,4-di-tert-butyl-5-methylphenyl)-4,4'-biphenylene diphosphite, and tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylene diphosphite. These phosphorus-based heat stabilizers may be used alone or in combination of two or more. Among these, from the viewpoint of further improving the heat aging resistance of the polyamide composition and reducing the amount of gas generated, the phosphorus-based heat stabilizer is preferably at least one selected from the group consisting of pentaerythritol-type phosphite compounds and tris(2,4-di-tert-butylphenyl)phosphite.

[0071] Examples of the pentaerythritol phosphite compound include, but are not limited to, 2,6-di-tert-butyl-4-methylphenyl-phenyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-methyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-2-ethylhexyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-isodecyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-isodecyl-pentaerythritol diphosphite, 6-di-tert-butyl-4-methylphenyl-lauryl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-isotridecyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-stearyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-cyclohexyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-benzyl-pentaerythritol diphosphite, 2,6-Di-tert-butyl-4-methylphenyl ethyl cellosolve-pentaerythritol diphosphite, 2,6-Di-tert-butyl-4-methylphenyl-butylcarbitol-pentaerythritol diphosphite, 2,6-Di-tert-butyl-4-methylphenyl-octylphenyl-pentaerythritol diphosphite, 2,6-Di-tert-butyl-4-methylphenyl-nonylphenyl pentaerythritol diphosphite, Bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-ethylphenyl)pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-2,6-di-tert-butylphenyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-2,4-di-tert-butylphenyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-2,4-di-tert-octylphenyl-pentaerythritol diphosphite, 2,Examples include 6-di-tert-butyl-4-methylphenyl-2-cyclohexylphenyl-pentaerythritol diphosphite, 2,6-di-tert-amyl-4-methylphenyl-phenyl pentaerythritol diphosphite, bis(2,6-di-tert-amyl-4-methylphenyl)pentaerythritol diphosphite, and bis(2,6-di-tert-octyl-4-methylphenyl)pentaerythritol diphosphite. These pentaerythritol-type phosphite compounds may be used alone or in combination of two or more.

[0072] Among these, from the viewpoint of reducing the amount of gas generated from the polyamide composition, the pentaerythritol phosphite compound is preferably one or more selected from the group consisting of bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-ethylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-amyl-4-methylphenyl)pentaerythritol diphosphite, and bis(2,6-di-tert-octyl-4-methylphenyl)pentaerythritol diphosphite, and more preferably bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite.

[0073] When a phosphorus-based heat stabilizer is used, the content of the phosphorus-based heat stabilizer in the polyamide composition is preferably 0.01% by mass or more and 1% by mass or less, more preferably 0.1% by mass or more and 1% by mass or less, relative to the total mass of the polyamide composition. When the content of the phosphorus-based heat stabilizer is within the above range, the heat aging resistance of the polyamide composition can be further improved, and the amount of gas generation can be further reduced.

[0074] Examples of the amine-based heat stabilizer include, but are not limited to, 4-acetoxy-2,2,6,6-tetramethylpiperidine, 4-stearoyloxy-2,2,6,6-tetramethylpiperidine, 4-acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-(phenylacetoxy)-2,2,6,6-tetramethylpiperidine, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 4-methoxy-2,2,6,6-tetramethylpiperidine, and 4-stearyloxy-2,2,6,6-tetramethylpiperidine. 4-cyclohexyloxy-2,2,6,6-tetramethylpiperidine, 4-benzyloxy-2,2,6,6-tetramethylpiperidine, 4-phenoxy-2,2,6,6-tetramethylpiperidine, 4-(ethylcarbamoyloxy)-2,2,6,6-tetramethylpiperidine, 4-(cyclohexylcarbamoyloxy)-2,2,6,6-tetramethylpiperidine, 4-(phenylcarbamoyloxy)-2,2,6,6-tetramethylpiperidine, bis(2,2,6,6-tetramethyl-4-piperidyl)-carbonate, bis( 2,2,6,6-tetramethyl-4-piperidyl)-oxalate, bis(2,2,6,6-tetramethyl-4-piperidyl)-malonate, bis(2,2,6,6-tetramethyl-4-piperidyl)-sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)-adipate, bis(2,2,6,6-tetramethyl-4-piperidyl)-terephthalate, 1,2-bis(2,2,6,6-tetramethyl-4-piperidyloxy)-ethane, α,α'-bis(2,2,6,6-tetramethyl-4-piperidyloxy)-p-xylene, biphenyl Bis(2,2,6,6-tetramethyl-4-piperidyl)tolylene-2,4-dicarbamate, bis(2,2,6,6-tetramethyl-4-piperidyl)-hexamethylene-1,6-dicarbamate, tris(2,2,6,6-tetramethyl-4-piperidyl)-benzene-1,3,5-tricarboxylate, tris(2,2,6,6-tetramethyl-4-piperidyl)-benzene-1,3,4-tricarboxylate, 1-[2-{3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy}butyl]-4-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]2,2,6,6-tetramethylpiperidine, a condensation product of 1,2,3,4-butanetetracarboxylic acid, 1,2,2,6,6-pentamethyl-4-piperidinol, and β,β,β',β'-tetramethyl-3,9-[2,4,8,10-tetraoxaspiro(5,5)undecane]diethanol, etc. These amine-based heat stabilizers may be used alone or in combination of two or more.

[0075] When an amine-based heat stabilizer is used, the content of the amine-based heat stabilizer in the polyamide composition is preferably 0.01% by mass or more and 1% by mass or less, more preferably 0.1% by mass or more and 1% by mass or less, relative to the total mass of the polyamide composition. When the content of the amine-based heat stabilizer is within the above range, the heat aging resistance of the polyamide composition can be further improved, and the amount of gas generation can be further reduced.

[0076] ((F3) Other resins) (F3) Other resins are not particularly limited, but examples include thermoplastic resins and rubber components, which will be described later.

[0077] Examples of thermoplastic resins include polystyrene-based resins such as atactic polystyrene, isotactic polystyrene, syndiotactic polystyrene, AS (acrylonitrile-styrene) resin, and ABS (acrylonitrile-butadiene-styrene) resin; acrylic resins such as polyacrylic acid, polyacrylic acid ester, and polymethyl methacrylate; and halogen-containing vinyl compound-based resins such as polyvinyl chloride and polyvinylidene chloride. These thermoplastic resins may be used alone or in combination of two or more.

[0078] Examples of rubber components include natural rubber, polybutadiene, polyisoprene, polyisobutylene, neoprene, polysulfide rubber, thiokol rubber, acrylic rubber, urethane rubber, silicone rubber, epichlorohydrin rubber, styrene-butadiene block copolymer (SBR), hydrogenated styrene-butadiene block copolymer (SEB), styrene-butadiene-styrene block copolymer (SBS), hydrogenated styrene-butadiene-styrene block copolymer (SEBS), styrene-isoprene block copolymer (SIR), hydrogenated styrene-isoprene block copolymer (SEP), styrene-isoprene-styrene block copolymer (SIS), hydrogenated styrene-isoprene-styrene block copolymer (SEPS), styrene-butadiene random copolymer, hydrogenated styrene-butadiene random copolymer, styrene-ethylene-propylene random copolymer, Examples of such rubbers include styrene-ethylene-butylene random copolymers, ethylene-propylene copolymers (EPR), ethylene-(1-butene) copolymers, ethylene-(1-hexene) copolymers, ethylene-(1-octene) copolymers, ethylene-propylene-diene copolymers (EPDM), and core-shell types such as butadiene-acrylonitrile-styrene-core-shell rubber (ABS), methyl methacrylate-butadiene-styrene-core-shell rubber (MBS), methyl methacrylate-butyl acrylate-styrene-core-shell rubber (MAS), octyl acrylate-butadiene-styrene-core-shell rubber (MABS), alkyl acrylate-butadiene-acrylonitrile-styrene-core-shell rubber (AABS), butadiene-styrene-core-shell rubber (SBR), and siloxane-containing core-shell rubbers such as methyl methacrylate-butyl acrylate siloxane. These rubber components may be used alone or in combination of two or more.

[0079] <Method of producing polyamide composition> There are no particular limitations on the method for producing the polyamide composition, as long as it is a production method that includes a step of melt-kneading raw material components including the above components (A) to (C). In the melt-kneading step, for example, when the raw material components are melt-kneaded in an extruder, the temperature of the extruder is preferably set to the melting point (Tm2) of the polyamide (A) + 30°C or less.

[0080] (A) Examples of a method for melt-kneading raw material components containing polyamide include the following method (1) or (2). (1) (A) A method in which polyamide and other raw materials are mixed using a tumbler, Henschel mixer, etc., and then fed into a melt kneader for kneading. (2) A method in which (A) polyamide is melted in a single-screw or twin-screw extruder and then other raw materials are compounded from a side feeder.

[0081] The components constituting the polyamide composition may be supplied to the melt kneader by supplying all of the components to the same supply port at once, or by supplying each component from a different supply port.

[0082] The melt-kneading temperature is preferably about 250°C or higher and 350°C or lower in terms of resin temperature. The melt-kneading time is preferably about 0.25 minutes or more and 5 minutes or less. The melt-kneading device is not particularly limited, and known devices such as melt-kneaders such as a single-screw or twin-screw extruder, a Banbury mixer, or a mixing roll can be used.

[0083] The amount of each component blended when producing the polyamide composition is the same as the content of each component in the polyamide composition described above.

[0084] <Application> The polyamide composition of the present embodiment can be suitably used as various molded articles and parts for, for example, automobiles, machinery industry, electrical and electronics, industrial materials, industrial materials, daily necessities and household goods, etc.

[0085] The polyamide composition of the present embodiment has excellent heat aging resistance, fluidity, and resistance to ion migration, and is therefore particularly suitable for use in electrical parts for automobiles, railways, and vehicles, industrial electrical parts, and electrical and electronic parts, specifically transmission parts, coil bobbins, electromagnetic device housings, connectors, wire harness connectors, motor parts, lamp sockets, combination switches, electronic part housings, overmolding resins for electrical equipment, and the like.

[0086] Electrical parts The electrical component of the present embodiment is formed by molding the polyamide composition.

[0087] The electrical component of this embodiment uses the polyamide composition, and therefore has excellent heat aging resistance and flowability, and does not undergo ion migration when energized. That is, in one embodiment, the present invention provides a method for improving the heat aging resistance, flowability, and ion migration resistance of an electrical component.

[0088] The molding method is not particularly limited, but examples thereof include commonly known plastic injection molding methods such as injection molding, overmolding, gas-assisted injection molding, etc. Among these, the electrical component of the present embodiment is preferably obtained by overmolding.

[0089] The temperature setting for the molding machine when molding the electrical component of this embodiment is preferably set within a range of from 5°C to 50°C higher than the melting point of the polyamide used, more preferably from 10°C to 40°C higher than the melting point of the polyamide used, and even more preferably from 15°C to 30°C higher than the melting point of the polyamide used. By setting the temperature for the molding machine at or below the upper limit mentioned above, melting and aggregation of the components (B) and (C) during melting and injection of the polyamide composition can be suppressed, and the components (B) and (C) can be sufficiently dispersed in the electrical component.

[0090] Examples of the electrical components of this embodiment include electrical components for automobiles, railways, and vehicles, industrial electrical components, and electrical and electronic components, specifically transmission components, coil bobbins, electromagnetic device housings, connectors, wire harness connectors, motor components, lamp sockets, combination switches, electronic component housings, and overmolding resins for electrical applications. [Example]

[0091] The present invention will be described in detail below with reference to specific examples and comparative examples, but the present invention is not limited to the following examples. In the examples, 1 kg / cm 2 means 0.098 MPa.

[0092] <Raw materials> Each raw material contained in the polyamide composition will be described below.

[0093] [(A) Polyamide] A-1: Polyamide 66 (PA66)

[0094] [(B) Polyethyleneimine] B-1: Polyethyleneimine, manufactured by BASF, trade name "Lupasol (registered trademark) FG"

[0095] [(C) Aromatic amine] C-1: 4,4'-bis(α,α-dimethylbenzyl)diphenylamine, manufactured by Ouchi Shinko Chemical Industry Co., Ltd., trade name "Nocrac CD" C-2: 2,2,4-trimethyl-1,2-dihydroquinoline polymer, manufactured by Ouchi Shinko Chemical Industry Co., Ltd., trade name "Nocrac 224"

[0096] [(D) Colorant] D-1: Carbon black (CB)

[0097] [(E) Inorganic filler] E-1: Glass fiber (GF) (manufactured by Nippon Electric Glass Co., Ltd.; ECS 03T-275H)

[0098] [(G) Conventional heat resistance improver] G-1: Hindered phenol antioxidant (manufactured by BASF Japan Ltd., product name "Irganox 1098") G-2: Copper iodide (CuI) (trade name "Copper iodide (I)", manufactured by Wako Pure Chemical Industries, Ltd.) G-3: Potassium iodide (KI) (trade name "Potassium iodide", manufactured by Wako Pure Chemical Industries, Ltd.)

[0099] <(A) Production of Polyamide> [Manufacturing Example 1] (Production of Polyamide A-1 (PA66)) Polyamide 66 was synthesized by carrying out a polyamide polymerization reaction using the "hot melt polymerization method" as follows. First, 1500 g of an equimolar salt of adipic acid and hexamethylenediamine was dissolved in 1500 g of distilled water to prepare a 50% by mass equimolar aqueous solution of the raw material monomers. This aqueous solution was placed in an autoclave with an internal volume of 5.4 L and purged with nitrogen. The mixture was concentrated by gradually releasing steam to a solution concentration of 70% by mass while stirring at a temperature of approximately 110°C to 150°C. The internal temperature was then raised to 220°C. At this time, the autoclave was pressurized to 1.8 MPa. The reaction was continued for 1 hour while maintaining the pressure at 1.8 MPa by gradually releasing steam until the internal temperature reached 245°C. The pressure was then reduced over 1 hour, and the autoclave was then maintained at a reduced pressure of 650 torr (86.66 kPa) for 10 minutes using a vacuum device, with the final internal temperature of the polymerization reaching 265°C. The mixture was then pressurized with nitrogen and formed into strands from the lower spinneret (nozzle), cooled with water, cut, and discharged as pellets. These were then dried at 100°C in a nitrogen atmosphere for 12 hours to obtain polyamide 66. Mw=35,000, Mw / Mn=2.0, and crystallization enthalpy ΔH=62 J / g.

[0100] <Physical properties of polyamide and polyamide composition> [Physical Properties 1] (Weight average molecular weight and molecular weight distribution) The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of (A) crystalline polyamide and (B) amorphous polyamide were measured using a gel permeation graph (GPC) (HLC-8020 manufactured by Tosoh Corporation, hexafluoroisopropanol solvent, converted into a PMMA (polymethyl methacrylate) standard sample (manufactured by Polymer Laboratory Co., Ltd.)). The molecular weight distribution (Mw / Mn) was calculated from the values.

[0101] [Physical Properties 2] (crystallization enthalpy ΔH and melting point) The crystallization enthalpies ΔH of (A) crystalline polyamide and (B) amorphous polyamide, and the melting points of the polyamide compositions obtained in the examples and comparative examples were measured in accordance with JIS-K7121 using a Diamond DSC manufactured by PERKIN-ELMER. Specifically, the measurements were performed as follows. First, under a nitrogen atmosphere, approximately 10 mg of sample was heated from room temperature to 300°C to 350°C (depending on the melting point of the sample) at a heating rate of 20°C / min. The highest endothermic peak (melting peak) temperature was designated Tm1 (°C). Next, the temperature was maintained at the highest temperature for 2 minutes. At this maximum temperature, the polyamide was in a molten state. The temperature was then lowered to 30°C at a cooling rate of 20°C / min. The exothermic peak that appeared at this time was designated the crystallization peak, and the crystallization peak temperature, Tc, and the crystallization peak area were designated the crystallization enthalpy, ΔH (J / g). After holding at 30°C for 2 minutes, the sample was heated from 30°C to 280°C to 300°C (depending on the melting point of the sample) at a heating rate of 20°C / min. The highest endothermic peak (melting peak) temperature that appeared at this time was designated the melting point, Tm2 (°C).

[0102] <Method for evaluating molded products> [Rating 1] (Liquidity) The polyamide resin composition pellets obtained in the examples and comparative examples were molded using an injection molding machine (S2000i100B, manufactured by FANUC CORPORATION) and a spiral flow mold 10 mm wide and 2 mm thick, and the spiral flow length (SFD) was measured (unit: cm). The conditions for the injection molding machine were set as follows: mold temperature 80°C, molten resin temperature 280°C, and injection pressure 30 MPa. A spiral flow length (SFD) of 28 cm or more was evaluated as having good fluidity.

[0103] [Rating 2] (heat aging resistance) The polyamide resin composition pellets obtained in the examples and comparative examples were molded into multipurpose test specimens (Type A) in accordance with ISO 3167 using an injection molding machine (S2000i100B, manufactured by FANUC Corporation). The injection molding conditions were set as follows: injection + dwell time 16 seconds, cooling time 10 seconds, mold temperature 80°C, and molten resin temperature 280°C. Using the obtained molded specimens, a tensile test was performed in accordance with ISO 527 at a pulling rate of 5 mm / min, and the tensile strength (unit: MPa) was measured. Furthermore, the multipurpose test specimens (Type A) were subjected to heat aging at 180°C for 1,000 hours in a hot air circulation oven. After cooling at 23°C for 24 hours or more, a tensile test was performed in accordance with ISO 527 at a pulling rate of 5 mm / min, and the tensile strength (unit: MPa) after heat aging was measured. Next, the ratio of the tensile strength after the thermal degradation test to the tensile strength before the thermal degradation test was calculated as a percentage (%), and the obtained value was defined as the tensile strength retention rate. Those with a tensile strength retention rate of 75% or more were evaluated as having good heat aging resistance.

[0104] [Rating 3] (ion migration) The polyamide resin composition pellets obtained in the examples and comparative examples were molded into a flat plate having a length of 90 mm, a width of 30 mm, and a thickness of 3 mm using an injection molding machine (S2000i100B, manufactured by FANUC CORPORATION). The conditions for the injection molding machine were set as follows: injection + pressure holding time 16 seconds, cooling time 10 seconds, mold temperature 80°C, and molten resin temperature 280°C. Aluminum tape (AL-50BT, 3M Japan Ltd.) was attached to the obtained flat plate as an electrode. The distance between the positive and negative electrodes was set to 1 mm, and a voltage of 800 V was applied for 500 hours at a constant temperature and humidity of 85°C and 85%. Those in which no ion migration occurred in the aluminum electrode were judged to be good.

[0105] <Method of producing polyamide composition> [Examples 1 to 2 and Comparative Examples 1 to 6] (Production of Polyamide Compositions PA-a1 and PA-b1 to PA-b6) Each polyamide composition was produced by the following method using each raw material component so as to have the composition shown in Table 1 below. The polyamide A-1 was dried in a nitrogen stream to adjust the moisture content to about 0.2% by mass before being used as a raw material for the polyamide composition.

[0106] The polyamide composition was produced using a twin-screw extruder (ZSK-26MC, manufactured by Coperion (Germany)). The twin-screw extruder had an upstream supply port in the first barrel from the upstream side of the extruder, a first downstream supply port in the sixth barrel, and a second downstream supply port in the ninth barrel. The extruder length (lx) / screw diameter (dx) ratio was 48, and the number of barrels was 12. In the twin-screw extruder, the temperature from the upstream supply port to the die was set to 295°C, the screw rotation speed was set to 250 rpm, and the discharge rate was set to 25 kg / h.

[0107] In a specific production method using the above production apparatus, (A) polyamide was fed into a twin-screw extruder through an upstream feed port, and other raw material components were fed into a first downstream feed port of the twin-screw extruder. The molten mixture extruded through a die head was cooled in the form of strands and pelletized to obtain pellets of each polyamide composition. The obtained pellets of polyamide composition were dried in a nitrogen stream to reduce the moisture content in the polyamide composition to 500 ppm or less.

[0108] The evaluation results of the molded articles using the polyamide compositions obtained in the examples and comparative examples are shown in Table 1 below.

[0109] [Table 1]

[0110] As can be seen from Table 1, the molded articles obtained by molding polyamide compositions PA-a1 to PA-a2 (Examples 1 to 2) containing polyamide, polyethyleneimine, and aromatic amine had excellent heat aging resistance and fluidity, and did not undergo ion migration when electricity was applied.

[0111] On the other hand, in a molded body obtained by molding polyamide composition PA-b1 (Comparative Example 1), which does not contain aromatic amines and contains polyamide and polyethyleneimine, no ion migration occurred when electricity was applied, but the heat aging resistance and fluidity were poor. Furthermore, in a molded body obtained by molding polyamide composition PA-b2 (Comparative Example 2), which does not contain polyethyleneimine but contains polyamide and aromatic amine, no ion migration occurred when electricity was applied, but the heat aging resistance and fluidity were poor. Furthermore, in the molded articles obtained by molding polyamide compositions PA-b3 to PA-b4 (Comparative Examples 3 and 4) containing polyamide and a hindered phenol-based antioxidant, which is a conventional heat resistance improver, no ion migration occurred when electricity was applied, but the heat aging resistance and fluidity were poor. Furthermore, a molded body obtained by molding polyamide composition PA-b5 (Comparative Example 5), which contains polyamide and conventional heat resistance improvers copper iodide and potassium iodide, had good heat aging resistance, but poor fluidity, and ion migration occurred when electricity was applied. In addition, in the polyamide composition PA-b6 which did not contain polyethyleneimine or aromatic amine but contained polyamide, ion migration did not occur when electricity was applied, but the heat aging resistance and fluidity were poor. [Industrial Applicability]

[0112] The polyamide composition of this embodiment can provide a polyamide composition that can be used to obtain electrical components that are excellent in heat aging resistance and fluidity and do not cause ion migration when energized. The electrical components of this embodiment are formed by molding the polyamide composition, and are excellent in heat aging resistance and fluidity and do not cause ion migration when energized. The method of this embodiment can improve the heat aging resistance and fluidity of electrical components, and can obtain electrical components that do not cause ion migration when energized.

Claims

1. comprising a polyamide, a polyethyleneimine, and an aromatic amine; Substantially halogen-free A polyamide composition comprising 0.70 parts by mass or more of the aromatic amine per 100.00 parts by mass of the polyamide.

2. The polyamide composition according to claim 1, comprising 0.20 parts by mass or more of the polyethyleneimine per 100.00 parts by mass of the polyamide.

3. The polyamide composition according to claim 1 or 2, further comprising an inorganic filler.

4. The polyamide composition according to any one of claims 1 to 3, which is used for electrical parts.

5. An electrical component obtained by molding the polyamide composition according to any one of claims 1 to 4.

6. A method for improving heat aging resistance, fluidity, and ion migration resistance of an electrical component, comprising: The method includes molding a polyamide composition containing a polyamide, a polyethyleneimine, and an aromatic amine to obtain an electrical component, The polyamide composition is substantially free of halogens and comprises 0.70 parts by weight or more of the aromatic amine per 100.00 parts by weight of the polyamide.

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