JP7679653B2 - Resin composition and molded article - Google Patents

Description

The present invention relates to a resin composition and a molded article.

Polyamide resins have excellent properties such as resistance to heat deformation, chemical resistance, and abrasion resistance, and are therefore widely used in automobile parts, electrical and electronic parts, industrial materials, etc. In particular, they are widely used in automobile parts such as intake manifolds, radiator tanks, canisters, engine covers, and other engine peripheral parts, as well as heat sinks, connectors, and other battery and motor peripheral parts.

In recent years, automobiles have been made lighter and downsized to improve fuel efficiency. This has resulted in a demand for thinner plastic parts, and the use environment temperature has tended to rise due to the increased density of parts. In other words, there is an increasing demand for durable materials that have high impact resistance per unit volume and little deterioration even when used for long periods of time under high temperature conditions of 100°C or higher.
However, conventional polyamide resins are insufficient in impact resistance, particularly in impact resistance under low temperature conditions, and in resistance to heat deterioration, and therefore their applications are currently limited.

Numerous methods have been proposed for improving the impact resistance of polyamide resins. For example, Patent Document 1 proposes a method of blending an acid-modified ethylene/propylene copolymer (acid-modified EPR) with polyamide, and Patent Document 2 proposes a method of blending an olefin-maleic anhydride copolymer with polyamide resin. Patent Document 3 proposes a method of blending a polyorganosiloxane graft copolymer with polyamide resin.

In addition, numerous methods have been proposed for improving the heat degradation resistance of polyamide resins. For example, Patent Document 4 proposes a technique for blending a copper compound and iron oxide, and Patent Document 5 proposes a method for blending an alkali metal compound and an ethylene-maleic anhydride copolymer with a polyamide resin.

Japanese Unexamined Patent Publication No. 59-131649 Special Publication No. 2014-503003 Japanese Patent Application Publication No. 5-98115 Special Publication No. 2008-527129 JP 2016-153459 A

However, the technologies described in Patent Documents 1 to 5 were insufficient in terms of impact resistance, particularly at low temperatures, and heat degradation resistance.

In view of the above-mentioned problems of the conventional technology, the present invention aims to provide a polyamide resin composition and a molded article thereof that have excellent impact resistance, particularly at low temperatures, and also have excellent resistance to thermal degradation.

That is, the present invention relates to the following.
[1] A resin composition comprising a polyamide resin (A), a rubber-containing graft polymer (B) having an epoxy group, and a polymer (C) containing a carboxy group and/or a derivative thereof.
[2] The ratio of the rubber-containing graft polymer (B) to 100 parts by mass of the polyamide resin (A) is 0.1 to 30 parts by mass, and the ratio of the polymer (C) is 0.1 to 10 parts by mass. [1] The resin composition according to the above.
[3] The resin composition according to [1] or [2], wherein the rubber-containing graft polymer (B) contains at least one of polyorganosiloxane and polyalkyl (meth)acrylate as a rubber component.
[4] The resin composition according to any one of [1] to [3], wherein the polymer (C) contains a dicarboxylic acid anhydride group.
[5] The resin composition according to any one of [1] to [4], wherein the acid value of the polymer (C) is 1 to 2500 mg KOH / g.
[6] The resin composition according to any one of [1] to [5], wherein the acid value of the polymer (C) is 20 to 200 mg KOH / g.
[7] The polyamide resin composition according to any one of [1] to [6], wherein the polymer (C) contains an α-olefin having 10 to 80 carbon atoms as a copolymerization component.
[8] A molded article comprising the resin composition according to any one of [1] to [7].

The present invention provides a polyamide resin composition and molded articles thereof that are excellent in impact resistance, particularly at low temperatures, and also in heat degradation resistance.

The following describes in detail the embodiments of the present invention, but the present invention is not limited to these descriptions, and can be modified as appropriate without departing from the spirit of the present invention, apart from the following examples. In the present invention, vinyl monomer means a compound having a polymerizable double bond, (meth)acrylic means acrylic or methacrylic, and (meth)acrylic acid ester means acrylic acid ester or methacrylic acid ester. In the present specification, "-" is used to mean that the numerical values before and after it are included as the lower and upper limits.

The resin composition according to this embodiment contains a polyamide resin (A), a rubber-containing graft polymer (B) containing an epoxy group, and a polymer (C) containing a carboxyl group and/or a derivative thereof.

[Polyamide resin (A)]
The resin composition according to the present embodiment contains a polyamide resin (A). Here, the polyamide resin is a polymer having an amide bond (-NHCO-) in the main chain. The polyamide resin (A) is not particularly limited, but examples thereof include polyamide resins obtained by condensation polymerization of diamines and dicarboxylic acids, polyamide resins obtained by ring-opening polymerization of lactams, polyamide resins obtained by self-condensation of aminocarboxylic acids, and copolymers obtained by copolymerization of two or more monomers constituting these polyamide resins. These may be used alone or in combination of two or more.
In the case of using them in combination, a method of using a blend of these polyamide resins or a method of using a polyamide resin obtained by copolymerizing a plurality of these polyamide raw materials can be mentioned.

The raw materials for polyamide resin are explained below.

<Diamine>
The diamine is not limited to the following, but examples thereof include aliphatic diamines, alicyclic diamines, and aromatic diamines.

The aliphatic diamines include, but are not limited to, linear saturated aliphatic diamines having 2 to 20 carbon atoms, such as ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, and tridecamethylenediamine; branched saturated aliphatic diamines having 3 to 20 carbon atoms, such as 2-methylpentamethylenediamine (also written as 2-methyl-1,5-diaminopentane), 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 2-methyloctamethylenediamine, and 2,4-dimethyloctamethylenediamine; and the like. Examples of the branched saturated aliphatic diamines include diamines having a substituent branched from the main chain.

The alicyclic diamine (also referred to as alicyclic diamine) is not limited to the following, but examples thereof include 1,4-cyclohexanediamine, 1,3-cyclohexanediamine, 1,3-cyclopentanediamine, etc.

Examples of the aromatic diamine include, but are not limited to, metaxylylenediamine, paraxylylenediamine, metaphenylenediamine, orthophenylenediamine, and paraphenylenediamine.

<Dicarboxylic acid>
The dicarboxylic acid is not limited to the following, but examples thereof include aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, and aromatic dicarboxylic acids.

Examples of the aliphatic dicarboxylic acid include, but are not limited to, linear or branched saturated aliphatic dicarboxylic acids having 3 to 20 carbon atoms, such as 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 dioic acid, and diglycolic acid.

Examples of the alicyclic dicarboxylic acid include, but are not limited to, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,3-cyclopentanedicarboxylic acid.
The number of carbon atoms in the alicyclic structure of the alicyclic carboxylic acid is not particularly limited, but is preferably 3 to 10, and more preferably 5 to 10, from the viewpoint of the balance between the water absorption property and the crystallinity of the resulting polyamide resin.

The alicyclic dicarboxylic acid may be unsubstituted or may have a substituent.
Examples of the substituent include, but are not limited to, alkyl groups having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a tert-butyl group.

The aromatic dicarboxylic acid is not limited to the following, but examples thereof include unsubstituted or substituted aromatic dicarboxylic acids having 8 to 20 carbon atoms.
Examples of the substituent include, but are not limited to, alkyl groups having 1 to 6 carbon atoms, aryl groups having 6 to 12 carbon atoms, arylalkyl groups having 7 to 20 carbon atoms, halogen groups such as a chloro group and a bromo group, alkylsilyl groups having 3 to 10 carbon atoms, sulfonic acid groups, and salts thereof such as a sodium salt thereof.
Examples of the aromatic dicarboxylic acid 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 dicarboxylic acid may further contain a polyvalent carboxylic acid having a valence of three or more, such as trimellitic acid, trimesic acid, or pyromellitic acid, within the scope of the present embodiment.
The above-mentioned diamines and dicarboxylic acids may each be used alone or in combination of two or more kinds.

<Lactam>
Examples of the lactam include, but are not limited to, butyrolactam, pivalolactam, ε-caprolactam, caprylolactam, enantholactam, undecanolactam, and laurolactam (dodecanolactam).
Among these, from the viewpoint of toughness, ε-caprolactam, laurolactam, etc. are preferred, and ε-caprolactam is more preferred.

<Aminocarboxylic acid>
The aminocarboxylic acid is not limited to the following, but examples thereof include the above-mentioned lactam ring-opened compounds (ω-aminocarboxylic acid, α,ω-aminocarboxylic acid, etc.).
From the viewpoint of increasing the crystallinity of the polyamide resin, the aminocarboxylic acid is preferably a linear or branched saturated aliphatic carboxylic acid having 4 to 14 carbon atoms and substituted with an amino group at the ω position. Examples of the aminocarboxylic acid include, but are not limited to, 6-aminocaproic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid. Other examples of the aminocarboxylic acid include para-aminomethylbenzoic acid.

The polyamide resin (A) is not limited to the following, but examples thereof include polyamide 4 (poly-α-pyrrolidone), polyamide 6 (polycaproamide), polyamide 11 (polyundecane amide), polyamide 12 (polydodecanamide), polyamide 46 (polytetramethylene adipamide), polyamide 56 (polypentamethylene adipamide), polyamide 66 (polyhexamethylene adipamide), polyamide 610 (polyhexamethylene sebacamide), polyamide 612 (polyhexamethylene adipamide), polyamide 620 (polyhexamethylene sebacamide), polyamide 622 (polyhexamethylene adipamide), polyamide 624 (polyhexamethylene adipamide), polyamide 626 (polyhexamethylene adipamide), polyamide 628 (polyhexamethylene sebacamide), polyamide 629 (polyhexamethylene adipamide), polyamide 630 (polyhexamethylene sebacamide), 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 637 (polyhexamethylene adipamide), polyamide 638 (polyhexamethylene adipamide), polyamide 639 (polyhexamethylene adipamide), polyamide 640 (polyhexamethylene adipamide), polyamide 641 (polyhexamethylene adipamide), polyamide 642 (polyhexamethylene adipamide), polyamide 643 (polyhexamethylene adipamide), polyamide 644 (polyhexamethylene adipamide), polyamide 645 (polyhexamethylene adipamide), polyamide 646 (polyhexamethylene adipamide), polyamide 646 (polyhexamethylene adipamide), polyamide Polyamide 116 (polyundecamethylene adipamide), 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 (polyhexamethylene (poly(2-methylpentamethylenecyclohexanedicarboxamide), polyamide 2Me-5C (poly(2-methylpentamethylenecyclohexanedicarboxamide), polyamide 9C (poly(nonamethylenecyclohexanedicarboxamide), 2Me-8C (poly(2-methyloctamethylenecyclohexanedicarboxamide), polyamide PBCM12 (polybis(4-aminocyclohexyl)methandodecamide), polyamide dimethyl PBCM12 (polybis(3-methyl-aminocyclohexyl)methandodecamide, polyamide Examples of polyamide resins 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 "Me" represents a methyl group.

In addition, when the above-mentioned various monomers are polymerized to produce polyamide resin (A), a terminal blocking agent can be further added to adjust the molecular weight. There are no particular limitations on the terminal blocking agent, and any known agent can be used.

Examples of the end-capping agent include, but are not limited to, monocarboxylic acids, monoamines, acid anhydrides, monoisocyanates, monoacid halides, monoesters, and monoalcohols.
These may be used alone or in combination of two or more.

Monocarboxylic acids that can be used as end-capping agents may be any that are reactive with amino groups, and include, but are not limited to, aliphatic monocarboxylic acids such as 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; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; and aromatic monocarboxylic acids such as benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, and phenylacetic acid.
These may be used alone or in combination of two or more.

The monoamine that can be used as the end-capping agent may be any monoamine that is reactive with a carboxyl group, and includes, but is not limited to, aliphatic monoamines such as methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, and dibutylamine; alicyclic monoamines such as cyclohexylamine and dicyclohexylamine; and aromatic monoamines such as aniline, toluidine, diphenylamine, and naphthylamine.
These may be used alone or in combination of two or more.

Examples of acid anhydrides that can be used as end-capping agents include, but are not limited to, phthalic anhydride, maleic anhydride, benzoic anhydride, acetic anhydride, and hexahydrophthalic anhydride.
These may be used alone or in combination of two or more.

Examples of monoisocyanates that can be used as an end-capping agent include, but are not limited to, phenyl isocyanate, tolyl isocyanate, dimethylphenyl isocyanate, cyclohexyl isocyanate, butyl isocyanate, and naphthyl isocyanate.
These may be used alone or in combination of two or more.

Examples of monoacid halides that can be used as an end-capping agent include, but are not limited to, halogen-substituted monocarboxylic acids such as monocarboxylic acids such as benzoic acid, diphenylmethanecarboxylic acid, diphenylsulfonecarboxylic acid, diphenylsulfoxidecarboxylic acid, diphenylsulfidecarboxylic acid, diphenylethercarboxylic acid, benzophenonecarboxylic acid, biphenylcarboxylic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, and anthracenecarboxylic acid.
These may be used alone or in combination of two or more.

Examples of monoesters that can be used as end-capping agents include, but are not limited to, glycerin monopalmitate, glycerin monostearate, glycerin monobehenate, glycerin monomontanate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol monobehenate, pentaerythritol monomontanate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monobehenate, sorbitan monomontanate, sorbitan dimontanate, sorbitan trimontanate, sorbitol monopalmitate, sorbitol monostearate, sorbitol monobehenate, sorbitol tribehenate, sorbitol monomontanate, and sorbitol dimontanate.
These may be used alone or in combination of two or more.

Examples of monoalcohols that can be used as an end-capping agent include, but are not limited to, propanol, butanol, pentanol, hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, nonadecanol, eicosanol, docosanol, tricosanol, tetracosanol, hexacosanol, heptacosanol, octacosanol, triacontanol (all of which are linear and branched), oleyl alcohol, behenyl alcohol, phenol, cresol (o-, m-, p-form), biphenol (o-, m-, p-form), 1-naphthol, and 2-naphthol.
These may be used alone or in combination of two or more.

The terminal group of the polyamide resin (A) used in the present invention is not particularly limited, but generally includes an amino group or a carboxy group. The molar ratio of the amount of amino terminal groups to the amount of carboxy terminal groups in the polyamide resin (A) (molar amount of amino terminal groups/molar amount of carboxy terminal groups) is not particularly limited, but is preferably 0.05 to 1.5, more preferably 0.1 to 1.0, and even more preferably 0.15 to 0.7. When the molar ratio of the amount of terminal groups is 0.05 or more, the reaction between the polyamide resin (A) and the rubber-containing graft polymer (B) containing an epoxy group and the polymer (C) containing a carboxy group and/or a derivative thereof described below during melt kneading becomes good, and the impact resistance tends to be good. In addition, when the molar ratio of the amount of terminal groups is 1.5 or less, the heat deterioration resistance of the molded article obtained from the resin composition tends to be better.

The molar amount of amino end groups in the polyamide is not particularly limited, but is preferably 10 to 100 μmol/g, more preferably 15 to 80 μmol/g, and even more preferably 30 to 80 μmol/g. When the amount of amino end groups is within the above range, the impact resistance of the resin composition tends to be superior.

Here, examples of methods for measuring the amount of amino end groups and the amount of carboxyl end groups in this specification include the 1H-NMR method and the titration method. In the 1H-NMR method, the amount can be determined from the integral value of the characteristic signal corresponding to each end group. In the titration method, for amino end groups, a method of titrating a phenol solution of polyamide resin with 0.1N hydrochloric acid, and for carboxyl end groups, a method of titrating a benzyl alcohol solution of polyamide resin with 0.1N sodium hydroxide can be used.

The method for adjusting the concentration of polyamide end groups is not particularly limited, but an example is the method using the aforementioned end-capping agent.

[Rubber-containing graft polymer (B) having epoxy groups]
The resin composition according to the present embodiment contains a rubber-containing graft polymer (B) having an epoxy group (hereinafter, may be simply referred to as graft polymer (B)).
The graft polymer (B) is obtained by graft polymerizing a polymer (β) with a vinyl monomer component (b) containing at least a vinyl monomer having an epoxy group, and contains a polymer (hereinafter also referred to as a "graft component") obtained by polymerizing the polymer (β) and the vinyl monomer component (b) containing a vinyl monomer having an epoxy group.

The polymer (β) is a rubber component, that is, it contains a polymer having a glass transition temperature (hereinafter sometimes referred to as Tg) of 0°C or less. The proportion of polymers having a Tg of 0°C or less in the polymer (β) is preferably 1% by mass or more, more preferably 10% by mass or more, even more preferably 30% by mass or more, particularly preferably 50% by mass or more, and especially preferably 70% by mass or more, while the upper limit is 100% by mass.

In addition, from the viewpoint of the heat deterioration resistance of the molded body, it is preferable that the polymer (β) contains at least one of polyorganosiloxane (β-1) (hereinafter also referred to as "rubber (β-1)") and poly(meth)acrylate (β-2) (hereinafter also referred to as "rubber (β-2)"). In particular, it is preferable that the polymer (β) contains both rubber (β-1) and rubber (β-2) because of their excellent impact strength improving effect.

In the present invention, the glass transition temperature of the polymer or the like can be measured by thermal analysis such as differential scanning calorimetry (DSC), dynamic mechanical analysis (DMS), and thermomechanical analysis (TMA). In particular, the Tg can be easily measured by the method for measuring the Tg of the polymer described in the Examples below. The Tg of the rubber component obtained can be predicted in advance using the FOX formula, so the composition of the rubber component can be considered based on this.

The number average particle diameter of the graft polymer (B) is not particularly limited, but is preferably 10 to 1000 nm, more preferably 20 to 700 nm, even more preferably 30 to 500 nm, particularly preferably 50 to 300 nm, and most preferably 70 to 250 nm. If the number average particle diameter is 10 nm or more, the impact resistance of the molded article is excellent. If the number average particle diameter is 1000 nm or less, the appearance smoothness of the molded article is excellent.

The method for measuring the number average particle diameter of the graft polymer (B) is not particularly limited, and examples thereof include dynamic light scattering, laser diffraction, centrifugal sedimentation, and observation with a transmission electron microscope.
Among them, the particle size distribution data can be easily obtained by the method described in the Examples below.

The number average particle size of the graft polymer (B) can be adjusted, for example, by the amount of emulsifier when the graft polymer (B) is produced by emulsion polymerization.

The mass average particle diameter of the graft polymer (B) is not particularly limited, but is preferably 10 to 1500 nm, more preferably 20 to 1000 nm, even more preferably 30 to 800 nm, particularly preferably 50 to 500 nm, and most preferably 70 to 350 nm. If the mass average particle diameter is 10 nm or more, the impact resistance of the molded article is excellent. If the mass average particle diameter is 1500 nm or less, the appearance smoothness of the molded article is excellent.

The ratio of the mass average particle size to the number average molecular weight of the graft polymer (B) (mass average particle size ÷ number average molecular weight) is not particularly limited, but is preferably 1.00 to 5.00, more preferably 1.00 to 3.00, even more preferably 1.00 to 2.50, particularly preferably 1.00 to 1.60, and most preferably 1.00 to 1.40. If the ratio of the mass average particle size to the number average molecular weight is 1.00 to 5.00, the impact resistance of the molded article is excellent.

(Polyorganosiloxane (β-1))
The polyorganosiloxane (β-1) is a polymer containing organosiloxane (b1-1) units.
The polyorganosiloxane (β-1) can be obtained by polymerizing an organosiloxane mixture containing an organosiloxane. The organosiloxane mixture may further contain components that are used as necessary.
Examples of components that may be used as necessary include at least one selected from the group consisting of a siloxane-based crosslinking agent (b1-2) (hereinafter also referred to as "crosslinking agent (b1-2)"), a siloxane-based crosslinking agent (b1-3) (hereinafter also referred to as "crosslinking agent (b1-3)"), and a siloxane oligomer having a terminal blocking group.

The organosiloxane (b1-1) may be a chain organosiloxane, an alkoxysilane compound, a cyclic organosiloxane, or the like, any of which may be used. Among these, alkoxysilane compounds and cyclic organosiloxanes are preferred, and cyclic organosiloxanes are particularly preferred due to their high polymerization stability and high polymerization rate.

As the alkoxysilane compound, a bifunctional alkoxysilane compound is preferable, and examples thereof include dimethyldimethoxysilane, dimethyldiethoxysilane, diethoxydiethylsilane, dipropoxydimethylsilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, etc. These can be used alone or in combination of two or more.

As the cyclic organosiloxane, those having 3 to 7 membered rings are preferred, and examples thereof include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltriphenylcyclotrisiloxane, tetramethyltetraphenylcyclotetrasiloxane, and octaphenylcyclotetrasiloxane. These can be used alone or in combination of two or more. Among these, octamethylcyclotetrasiloxane is preferred because the particle size distribution can be easily controlled.

As the organosiloxane (b1-1), from the viewpoint of obtaining a graft polymer (B) capable of increasing the impact resistance of the molded article, at least one selected from the group consisting of cyclic dimethylsiloxane and bifunctional dialkylsilane compounds is preferred.

Cyclic dimethylsiloxane is a cyclic siloxane having two methyl groups on the silicon atom, and examples thereof include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane. These can be used alone or in combination of two or more.

A bifunctional dialkylsilane compound is a silane compound having two alkoxy groups and two alkyl groups on a silicon atom, and examples of such compounds include dimethyldimethoxysilane, dimethyldiethoxysilane, diethoxydiethylsilane, and dipropoxydimethylsilane. These compounds can be used alone or in combination of two or more.

The crosslinking agent (b1-2) is preferably one having a siloxy group. Examples of the crosslinking agent (b1-2) include trifunctional or tetrafunctional silane-based crosslinking agents such as trimethoxymethylsilane, triethoxyphenylsilane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, and tetrabutoxysilane. Among these, tetrafunctional crosslinking agents are preferred, and tetraethoxysilane is more preferred.

The content of the crosslinking agent (b1-2) is preferably 0 to 10 mass% and more preferably 0 to 5 mass% in 100 mass% of the organosiloxane mixture. If the content of the crosslinking agent (b1-2) is 10 mass% or less, a graft polymer (B) that can improve the impact resistance of the molded article can be obtained.

The crosslinking agent (b1-3) has a siloxy group (--Si--O--) and also has a functional group polymerizable with a vinyl monomer.
By using the crosslinking agent (b1-3), the vinyl monomer component (b) can be effectively graft polymerized, and the molded article to which the graft polymer (B) has been added can have a more improved appearance smoothness.
In addition, by using a crosslinking agent (b1-3) when using a combination of polyorganosiloxane (β-1) and poly(meth)acrylate (β-2), the bond between the polyorganosiloxane (β-1) and the poly(meth)acrylate (β-2) can be strengthened, and a graft polymer (B) can be obtained that can improve the impact resistance of the molded article.

The crosslinking agent (b1-3) may, for example, be a siloxane represented by the following formula (I).
R-Si(R1)n(OR2)(3-n) (I)
In formula (I), R1 represents a methyl group, an ethyl group, a propyl group, or a phenyl group. R2 represents an organic group such as a hydrocarbon group, and is preferably, for example, a methyl group, an ethyl group, a propyl group, or a phenyl group. n represents 0, 1, or 2. R represents a functional group represented by any of the following formulae (I-1) to (I-4).
CH ₂ =C(R3)-COO-(CH ₂ )p- (I-1)
_CH2 =C(R4) _-C6H4- (I- ₂ )
CH ₂ =CH- (I-3)
HS-(CH ₂ )p- (I-4)
In these formulas, R3 and R4 each independently represent a hydrogen atom or a methyl group, and p represents an integer of 1 to 6.

The functional group represented by formula (I-1) can be, for example, a methacryloyloxyalkyl group. Examples of siloxanes having this group include the following: β-methacryloyloxyethyldimethoxymethylsilane, γ-methacryloyloxypropylmethoxydimethylsilane, γ-methacryloyloxypropyldimethoxymethylsilane, γ-methacryloyloxypropyltrimethoxysilane, γ-methacryloyloxypropylethoxydiethylsilane, γ-methacryloyloxypropyldiethoxymethylsilane, δ-methacryloyloxybutyldiethoxymethylsilane, etc.

An example of the functional group represented by formula (I-2) is a vinylphenyl group. An example of a siloxane having this group is vinylphenylethyldimethoxysilane.

Examples of siloxanes having a functional group represented by formula (I-3) include vinyltrimethoxysilane and vinyltriethoxysilane.

The functional group represented by formula (I-4) can be a mercaptoalkyl group. Examples of siloxanes having this group include the following: γ-mercaptopropyldimethoxymethylsilane, γ-mercaptopropylmethoxydimethylsilane, γ-mercaptopropyldiethoxymethylsilane, γ-mercaptopropylethoxydimethylsilane, γ-mercaptopropyltrimethoxysilane, etc.

These crosslinking agents (b1-3) can be used alone or in combination of two or more. As the crosslinking agent (b1-3), 3-methacryloxypropylmethyldimethoxysilane is preferred because it has excellent reactivity with other vinyl monomer components and can produce a graft polymer (B) that has excellent impact strength improving effects.

The content of the crosslinking agent (b1-3) is preferably 0.05 to 20 mass% in 100 mass% of the organosiloxane mixture, more preferably 0.1 to 10 mass%, and even more preferably 0.5 to 5 mass%. By making the content of the siloxane-based graft crosslinking agent (b1-3) 0.05 to 20 mass%, it is possible to obtain a graft polymer (B) that has an excellent effect of improving impact strength.

The number average particle diameter of the polyorganosiloxane (β-1) is not particularly limited, but is preferably 1 to 900 nm, more preferably 10 to 600 nm, and particularly preferably 30 to 200 nm. If the number average particle diameter of the polyorganosiloxane (β-1) is within the range of 1 to 900 nm, it is easy to adjust the number average particle diameter of the graft polymer (B) to within the range of 10 to 1000 nm.

The number average particle size (Dn) of polyorganosiloxane (β-1) can be measured using the same method as the number average particle size of the graft polymer (B) described above.

(Poly(meth)acrylate polymer (β-2))
The poly(meth)acrylate (β-2) is a polymer obtained by polymerizing a vinyl monomer (b2) containing a (meth)acrylate component, and has units based on the vinyl monomer.

The vinyl monomer component (b2) constituting the poly(meth)acrylate (β-2) comprises one or more vinyl monomers and includes a (meth)acrylate monomer (hereinafter also referred to as "monomer (b2-1)").
The vinyl monomer component (b2) may further contain, in addition to the monomer (b2-1), at least one selected from the group consisting of a monofunctional monomer copolymerizable with the monomer (b2-1) (hereinafter also referred to as "monomer (b2-2)") and a polyfunctional monomer copolymerizable with the monomer (b2-1) (hereinafter also referred to as "monomer (b2-3)").
The composition ratio of each monomer may be selected so that the Tg of the resulting polymer is 0° C. or less.

Examples of the monomer (b2-1) include alkyl acrylates such as methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, and n-octyl acrylate; and alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, t-butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, tridecyl methacrylate, and stearyl methacrylate.
Among these, since the impact resistance of the molded article becomes better, it is preferable to contain at least one monomer selected from the group consisting of ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, and n-octyl acrylate, and it is more preferable to contain n-butyl acrylate.
These monomers (b2-1) can be used alone or in combination of two or more.

Examples of the monomer (b2-2) include aromatic vinyl monomers such as styrene and α-methylstyrene, cyanide vinyl monomers such as acrylonitrile and methacrylonitrile, and various vinyl monomers such as (meth)acrylic group-modified silicones. These monomers (b2-2) can be used alone or in combination of two or more.

Examples of the monomer (b2-3) include ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, ethylene glycol diacrylate, propylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, divinylbenzene, polyfunctional (meth)acrylic group-modified silicone, allyl methacrylate, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, and the like.
Among these, at least one selected from the group consisting of allyl methacrylate, triallyl cyanurate and triallyl isocyanurate is preferred, and allyl methacrylate is more preferred, since the impact resistance of the molded article is improved.
These monomers (b2-3) can be used alone or in combination of two or more.

When the polymer (β) contains both polyorganosiloxane (β-1) and poly(meth)acrylate polymer (β-2), the method of production is not particularly limited. In a latex containing either polyorganosiloxane (β-1) or poly(meth)acrylate polymer (β-2), the monomer component constituting the other polymer may be polymerized, or the polymer latexes of polyorganosiloxane (β-1) and poly(meth)acrylate polymer (β-2) obtained by polymerizing each separately may be mixed. However, a method of polymerizing vinyl monomer component (b2) constituting poly(meth)acrylate polymer (β-2) in the presence of latex containing polyorganosiloxane (β-1) is preferred because it results in better impact strength of the molded product.

The method of polymerizing the vinyl monomer component (b2) in the presence of a latex containing polyorganosiloxane (β-1) is not particularly limited, and examples thereof include (i) a method of adding the vinyl monomer component (b2) dropwise to a latex containing polyorganosiloxane (β-1) and polymerizing it, (ii) a method of adding a part of the vinyl monomer component (b2) to a latex containing polyorganosiloxane (β-1) under conditions in which polymerization does not start, impregnating the particles of polyorganosiloxane (β-1), initiating polymerization, and then adding the remaining part of the vinyl monomer component (b2) dropwise or all at once and polymerizing it, and (iii) a method of adding the entire amount of the vinyl monomer component (b2) to a latex containing polyorganosiloxane (β-1) under conditions in which polymerization does not start, impregnating the particles of polyorganosiloxane (β-1), and then polymerizing it.

As a method for producing polymer (A), among the above, a method in which the entire amount of vinyl monomer component (b2) is added to a latex containing polyorganosiloxane (β-1) under conditions in which polymerization does not start, and the polyorganosiloxane (β-1) particles are impregnated with the vinyl monomer component (b2), and then polymerized, is preferred, because this method results in superior impact strength of the molded article.

From the viewpoint of impact resistance of the molded article, the proportion of monomer (b2-1) is preferably 60 to 100 mass% relative to 100 mass% of vinyl monomer component (b2), more preferably 70 to 99.9 mass%, even more preferably 80 to 99.9 mass%, and particularly preferably 90 to 99.9 mass%.

From the viewpoint of impact resistance of the molded article, the proportion of monomer (b2-2) is preferably 0 to 40% by mass, more preferably 0 to 30% by mass, even more preferably 0 to 20% by mass, and particularly preferably 0 to 10% by mass, relative to 100% by mass of vinyl monomer component (b2).

The proportion of the monomer (b2-3) is preferably 0.1 to 4% by mass based on 100% by mass of the vinyl monomer component (b2).
From the viewpoint of further increasing the impact resistance of the molded article, the proportion of the monomer (b2-3) is more preferably 0.1 to 2 mass%, and even more preferably 0.1 to 1 mass%, based on 100 mass% of the vinyl monomer component (b2).
From the viewpoint of further improving the colored appearance of the molded article, the proportion of the monomer (b2-3) is more preferably 0.5 to 4 mass%, and even more preferably 1 to 4 mass%, based on 100 mass% of the vinyl monomer component (b2).
From the viewpoint of the melt flowability during molding and the balance between the colored appearance and impact resistance of the molded article, the proportion of the monomer (b2-3) is more preferably 0.3 to 3 mass%, and even more preferably 0.5 to 2.5 mass%, relative to 100 mass% of the vinyl monomer component (b2).

The content of polymer (β) in 100% by mass of graft polymer (B) is not particularly limited, but is preferably 10 to 95% by mass, more preferably 20 to 95% by mass, even more preferably in the range of 30 to 93% by mass, and most preferably in the range of 50 to 90% by mass.

By making the content of polymer (β) 10% by mass or more, the impact strength improving effect when graft polymer (B) is added becomes better, and by making it 95% by mass or less, the dispersibility of graft polymer (B) in the molded product becomes better, and the appearance of the obtained molded product becomes good.

The content of polyorganosiloxane (β-1) in 100% by mass of polymer (β) is 0 to 100% by mass, more preferably 1 to 90% by mass, even more preferably 1 to 80% by mass, particularly preferably 2 to 50% by mass, and most preferably 3 to 30% by mass.

By containing polyorganosiloxane (β-1) in graft polymer (B), the effect of improving low-temperature impact strength when graft polymer (B) is added is excellent.

The content of poly(meth)acrylate polymer (β-2) in 100% by mass of polymer (β) is 0 to 100% by mass, more preferably 10 to 99% by mass, even more preferably 20 to 99% by mass, particularly preferably 50 to 98% by mass, and most preferably 70 to 97% by mass.

By containing polyorganosiloxane (β-2) in graft polymer (B), a good balance between the impact strength improvement effect and pigment colorability is achieved when graft polymer (B) is added.

(Vinyl Monomer (b))
The vinyl monomer component (b) includes a vinyl monomer (b-1) having an epoxy group.

Examples of the vinyl monomer (b-1) having an epoxy group include glycidyl (meth)acrylate, vinyl glycidyl ether, allyl glycidyl ether, glycidyl ether of a hydroxyalkyl (meth)acrylate, glycidyl ether of a polyalkylene glycol (meth)acrylate, and glycidyl itaconate.
Of these, glycidyl methacrylate is preferred.

Furthermore, the vinyl monomer (b) may contain another vinyl monomer (b-2) that is copolymerizable with the vinyl monomer (b-1) having an epoxy group.

The vinyl monomer (b-2) is not particularly limited, but examples thereof include various vinyl monomers such as (meth)acrylate monomers having no epoxy groups, aromatic vinyl monomers having no epoxy groups, and cyanide vinyl monomers having no epoxy groups.

Examples of (meth)acrylate monomers that do not have an epoxy group include alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, and i-butyl methacrylate; and alkyl acrylates such as methyl acrylate, ethyl acrylate, and n-butyl acrylate.

Examples of aromatic vinyl monomers that do not have an epoxy group include styrene, alkyl-substituted styrenes (p-methylstyrene, m-methylstyrene, o-methylstyrene, 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,4-dimethylstyrene, 3,5-dimethylstyrene, p-ethylstyrene, m-ethylstyrene, o-ethylstyrene, etc.), alkyl-substituted isopropenylbenzenes (isopropenylbenzene (α-methylstyrene), isopropenyltoluene, isopropenylethylbenzene, isopropenylpropylbenzene, isopropenylbutylbenzene, isopropenylpentylbenzene, isopropenylhexylbenzene, isopropenyloctylbenzene, etc.), and 1,1-diphenylethylene. Among these, styrene and α-methylstyrene are preferred because they can suppress the generation of cullets.

Examples of vinyl cyanide monomers having no epoxy group include acrylonitrile, methacrylonitrile, ethacrylonitrile, and fumaronitrile.
These may be used alone or in combination of two or more.

In 100% by mass of the vinyl monomer component (b), the content of the vinyl monomer (b-1) having an epoxy group is preferably 1% by mass or more, more preferably 3% by mass or more, while it is preferably 80% by mass or less, more preferably 50% by mass or less, particularly preferably 30% by mass or less, and most preferably 20% by mass or less. By making the content of the vinyl monomer (b-1) having an epoxy group 1% by mass or more, when added to a polyamide resin, it reacts with the polyamide resin (A) and the polymer (C) containing a carboxy group and its derivative described below, improving the interfacial strength with the polyamide resin (A), and providing an excellent effect of improving impact strength. Furthermore, if the content is 80% by mass or less, the presence of the vinyl monomer (b-2) or (b-3) makes it easier to seal the ends of the polyamide resin (A), providing an excellent effect of improving heat deterioration resistance.

The vinyl monomer constituting the vinyl monomer component (b) is preferably selected so that the glass transition temperature of the graft component (polymer obtained by polymerizing the vinyl monomer component (b)) is 70°C or higher. The Tg of the graft component is more preferably 80°C or higher, and even more preferably 90 to 105°C. If the Tg of the graft component is 70°C or higher, the powder properties (powder fluidity and particle size) of the graft polymer (B) obtained by carrying out the powder recovery process after graft polymerization of the vinyl monomer component (b) will be good.

The Tg of the graft component can be predicted in advance using the FOX formula. In this case, the Tg value of each homopolymer obtained by polymerizing each monomer unit constituting the vinyl monomer component (b) can be, for example, the value described in "POLYMER HANDBOOK" (Wiley Interscience, 1999). In addition, the Tg value of a monomer component not described can be calculated using Bicer Ano's method "Prediction of Polymer Properties" (MARCEL DEKKER, 2002).

(Method for Producing Graft Polymer (B))
The graft polymer (B) can be produced by graft polymerizing the vinyl monomer component (b) onto the polymer (β).

A preferred method for producing the graft polymer (B) is to add the vinyl monomer component (b) to the latex of the polymer (β) and graft polymerize the vinyl monomer component (b) in the latex. In this case, if the vinyl monomer component (b) contains multiple monomer components, the components may be mixed uniformly and then added, or each component may be added individually, or multiple solutions with different mixing ratios of each component may be added in sequence.

The latex of polymer (β) is preferably produced by polymerizing vinyl monomer component (b2) constituting poly(meth)acrylate (β-2) in the presence of latex containing polyorganosiloxane (β-1).

The vinyl monomer component (b) can form a graft polymer with the polymer (β) by chemically bonding with the crosslinking agent (b1-3) contained in the polyorganosiloxane (β-1) and/or the unsaturated component (vinyl component) derived from the multifunctional monomer (b2-3) contained in the poly(meth)acrylate (β-2).

To improve the efficiency of this grafting, polyfunctional monomers such as ethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, ethylene glycol diacrylate, propylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, divinylbenzene, polyfunctional (meth)acrylic group-modified silicone, allyl methacrylate, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, etc. can be polymerized in advance before adding the vinyl monomer component (b).

When the vinyl monomer component (b) is polymerized, a chain transfer agent may be used for the purpose of adjusting the molecular weight of the THF-soluble portion.
Examples of the chain transfer agent include mercaptans such as n-dodecyl mercaptan, t-dodecyl mercaptan, n-octyl mercaptan, n-tetradecyl mercaptan, n-hexyl mercaptan, and n-butyl mercaptan; halogen compounds such as carbon tetrachloride and ethylene bromide; α-methylstyrene dimer, etc. These chain transfer agents may be used alone or in combination of two or more.

The amount of the chain transfer agent used is preferably 0 to 2.0% by mass relative to 100% by mass of the vinyl monomer component (b). By using an amount of the chain transfer agent of 2.0% by mass or less, the impact resistance of the resulting molded article is superior.

After the vinyl monomer component (b) is graft polymerized, the graft polymer (B) may be recovered as a powder from the resulting latex of the graft polymer (B).
When the graft polymer (B) is recovered as a powder, a direct drying method such as a spray drying method or a coagulation method can be used. In the coagulation method, the amount of polymerization aid residues contained in the obtained powder, such as the emulsifier used during polymerization and its coagulation salt, initiator, etc., can be reduced in the washing step after coagulation. On the other hand, in the direct drying method, the aids added during polymerization can be generally allowed to remain in the obtained powder. These powder recovery methods can be appropriately selected to make the graft polymer (B) remain in a preferable state when added to a thermoplastic resin.

The spray drying method is a method in which the latex of the graft polymer (B) is sprayed in the form of fine droplets in a dryer and then dried by applying a heated gas for drying. Methods for generating fine droplets include, for example, a rotating disk type, a pressure nozzle type, a two-fluid nozzle type, and a pressurized two-fluid nozzle type. The capacity of the dryer may be anything from a small capacity for laboratory use to a large capacity for industrial use. The temperature of the heating gas for drying is preferably 200°C or less, more preferably 120 to 180°C. Two or more types of graft copolymer latexes produced separately can also be spray-dried together. Furthermore, in order to improve powder properties such as blocking during spray drying and bulk density, optional components such as silica can be added to the latex of the graft polymer (B) and then spray-dried.

The coagulation method involves coagulating the latex of the graft polymer (B), separating the graft polymer (B), recovering it, and drying it. First, the latex of the graft polymer (B) is poured into hot water in which a coagulant has been dissolved, and the graft polymer (B) is separated by salting out and coagulating it. Next, the separated wet graft polymer (B) is dehydrated, etc., and the graft polymer (B) with a reduced water content is recovered. The recovered graft polymer (B) is dried using a squeeze dehydrator or a hot air dryer.

Examples of coagulants include inorganic salts such as aluminum chloride, aluminum sulfate, sodium sulfate, magnesium sulfate, sodium nitrate, and calcium acetate, and acids such as sulfuric acid, with calcium acetate being particularly preferred. These coagulants can be used alone or in combination of two or more.

It is also possible to directly send the graft polymer (B) discharged from the squeeze dehydrator or extruder to an extruder or molding machine that produces a resin composition without recovering it, and mix it with a thermoplastic resin to obtain a molded product.

[Polymer (C) containing a carboxy group or a derivative thereof]
The resin composition according to the present embodiment includes a polymer (C) containing a carboxy group and/or a derivative thereof. Examples of the derivative of the carboxy group include a halogenated acyl group, a dicarboxylic anhydride group, an ester group, an amide group, and a nitrile group.

Among them, the polymer (C) preferably contains a carboxy group and/or a dicarboxylic anhydride group, and particularly preferably contains a dicarboxylic anhydride group, because it has excellent quality stability during storage, excellent reactivity with the polyamide resin (A) and the graft polymer (B), excellent effect of improving the heat deterioration resistance of the resin composition, and excellent impact resistance.

The carboxy group or a derivative thereof may be present in either the main chain or the side chain of the polymer (C).
In producing the polymer (C), a monomer (c-1) containing a carboxy group or a derivative thereof and another copolymerizable monomer (c-2) are used and copolymerized to obtain the polymer (C) containing a carboxy group or a derivative thereof in the main chain. Alternatively, a polymer (γ) serving as a base material is prepared in advance, radicals are generated by an organic peroxide or a thermal decomposition method, etc., and the monomer (c-1) containing a carboxy group or a derivative thereof is reacted with the polymer (γ) to obtain the polymer (C) containing a carboxy group or a derivative thereof in the side chain.

Among these, it is preferable that the main chain of the polymer (C) contains a carboxy group or a derivative thereof, since this has excellent reactivity with the polyamide resin (A) and the graft polymer (B), is effective in improving the heat deterioration resistance of the resin composition, and also has excellent impact resistance.

The monomer (c-1) containing a carboxy group or a derivative thereof is not particularly limited, but examples thereof include carboxy group-containing monomers such as (meth)acrylic acid, maleic acid, methylmaleic acid, fumaric acid, methylfumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, glutaconic acid, and norbornane-5-ene-2,3-dicarboxylic acid, and acid anhydride group-containing monomers such as maleic anhydride, itaconic anhydride, citraconic anhydride, and 5-norbornene-2,3-dicarboxylic anhydride. These may be used alone or in combination of two or more.

Among these, as the acid anhydride group-containing monomer, since it has excellent reactivity with the polyamide resin (A) and the graft polymer (B), it is effective in improving the heat deterioration resistance of the resin composition, and also has excellent impact resistance. Therefore, it is preferable that the monomer (c-1) is an acid anhydride group-containing monomer having 4 or more carbon atoms, while it is preferable that the monomer has 15 or less carbon atoms, and it is even more preferable that the monomer has 10 or less carbon atoms, and maleic anhydride is preferable.

The copolymerizable monomer (c-2) is not particularly limited, and examples thereof include aliphatic olefin monomers such as ethylene, propylene, 1-butene, 2-methyl-1-butene, pentene, hexene, and 4-methyl-1-pentene; alicyclic olefin monomers such as cyclohexene, vinylcyclohexane, and norbornene; diene monomers such as butadiene, isoprene, hexadiene, cyclopentadiene, dicyclopentadiene, and divinylbenzene; alkyl methacrylate monomers such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, and i-butyl methacrylate; alkyl acrylate monomers such as methyl acrylate, ethyl acrylate, and n-butyl acrylate; aromatic vinyl monomers such as styrene, alkyl-substituted styrene, and alkyl-substituted isopropenylbenzene; and cyanide vinyl monomers such as acrylonitrile and methacrylonitrile.
These may be used alone or in combination of two or more.

Among these, since the compatibility with the polyamide resin (A) is excellent and the thermal decomposition resistance when made into the polymer (C) is also excellent, it is preferable that the monomer (c-2) contains an aliphatic olefin monomer, and it is even more preferable that it contains an α-olefin monomer. Among these, the number of carbon atoms of the α-olefin is preferably 10 or more, more preferably 16 or more, and even more preferably 24 or more, while it is preferably 80 or less, more preferably 72 or less, and even more preferably 64 or less.

By including an α-olefin monomer having 10 to 80 carbon atoms, the reactivity between the polymer (C) and the polyamide resin (A) is further increased, making it easier to control the melt viscosity of the resin composition.

Examples of components constituting the polymer (γ) serving as the base material include aliphatic olefins such as ethylene, propylene, 1-butene, 2-methyl-1-butene, pentene, hexene, and 4-methyl-1-pentene; alicyclic olefins such as cyclohexene, vinylcyclohexane, and norbornene; dienes such as butadiene, isoprene, hexadiene, cyclopentadiene, dicyclopentadiene, and divinylbenzene; alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, and i-butyl methacrylate; alkyl acrylates such as methyl acrylate, ethyl acrylate, and n-butyl acrylate; aromatic vinyls such as styrene, alkyl-substituted styrene, and alkyl-substituted isopropenylbenzene; and vinyl cyanides such as acrylonitrile and methacrylonitrile.
These may be one kind of homopolymer or two or more kinds of copolymers. Furthermore, the obtained polymer may be subjected to a post-treatment such as hydrogenation.

Among these, since the polymer (γ) has excellent compatibility with the polyamide resin (A) and has excellent thermal decomposition resistance when made into the polymer (C), it is preferable that the polymer (γ) contains a polymer derived from a monomer group containing an aliphatic olefin monomer, and it is even more preferable that the polymer (γ) contains a polymer derived from a monomer group containing ethylene or propylene.

From the viewpoint of ease of handling, the melting point of polymer (C) is preferably 40°C or higher and 170°C or lower. If it is 40°C or higher, the heat deformation resistance of the resin composition is unlikely to be impaired, and if it is 170°C or lower, it can be melted quickly during the melt-kneading process and mixed well with polyamide resin (A). From the viewpoint of handling, it is preferably 50°C or higher and 130°C or lower, and more preferably 60°C or higher and 90°C or lower.

The acid value of the polymer (C) can be adjusted by the ratio of the monomer (c-1) containing a carboxy group or a derivative thereof used, and is not particularly limited, but is preferably 1 mgKOH/g or more, more preferably 10 mgKOH/g or more, particularly preferably 15 mgKOH/g or more, and most preferably 20 mgKOH/g or more, while it is preferably 2500 mgKOH/g or less, more preferably 1000 mgKOH/g or less, particularly preferably 500 mgKOH/g or less, and most preferably 200 mgKOH/g or less. By adjusting the acid value to 1 mgKOH/g or more, the reactivity with the polyamide resin (A) becomes good, and the melt viscosity adjustment effect when the polymer (C) is added is easily obtained. In addition, by adjusting the acid value to 2500 mgKOH/g or less, the melt viscosity increase effect due to the addition of the polymer (C) can be moderated, and the influence on the molding flowability due to a slight uncontrollable change in the amount of addition such as a measurement error can be suppressed, and the handling is excellent.

The acid value of polymer (C) can be determined by neutralization titration or potentiometric titration, but neutralization titration is particularly preferred. In neutralization titration, polymer (C) is dissolved in chloroform, phenolphthalein is added as an indicator, and the acid value is determined by titrating with an ethanolic solution of potassium hydroxide.

The molecular weight of the polymer (C) is not particularly limited, but the mass average molecular weight is preferably from 1,000 to 200,000, more preferably from 1,000 to 150,000, even more preferably from 3,000 to 100,000, and most preferably from 10,000 to 50,000.
By making the mass average molecular weight 1,000 or more, the thermal decomposition resistance of the polymer (C) is improved and gas generation during molding can be suppressed. Also, by making the mass average molecular weight 200,000 or less, the dispersibility of the polymer (C) in the molded article is improved and the molded article has excellent external smoothness.

The mass average molecular weight can be calculated using gel permeation chromatography (GPC). Specifically, a solvent in which the compound dissolves, such as hexafluoroisopropanol, is used as the mobile phase, and polymethyl methacrylate (PMMA) or polystyrene with a known molecular weight is used as the standard substance. The column is matched to the solvent. For example, when hexafluoroisopropanol is used, the mass average molecular weight can be measured using "Shodex GPC HFIP-806M" and/or "Shodex GPC HFIP-LG" manufactured by Shimadzu GLC Co., Ltd. and a differential refractometer as the detector.

There are no particular limitations on the form of the polymer (C), but from the viewpoint of ease of handling during kneading, it is preferable for it to be in a solid form that can be handled, such as rubber, wax, or clay, and it is even more preferable for it to be in a powder form obtained by finely crushing these.

[Resin composition]
The resin composition according to this embodiment contains a polyamide resin (A), a graft polymer (B), and a polymer (C).

The graft polymer (B) can improve the impact resistance and heat deterioration resistance by reacting with the polyamide resin (A) and the polymer (C) during melt-kneading, and the degree of improvement can be freely controlled by the content of the graft polymer (B).
In addition, the polymer (C) can improve the heat deterioration resistance and impact resistance by reacting with the polyamide resin (A) and the graft polymer (B) during melt-kneading, and the degree of improvement can be freely controlled by the content of the polymer (C).

The ratio of the graft polymer (B) to 100 parts by mass of the polyamide resin (A) is not particularly limited, but is preferably 0.1 parts by mass or more, preferably 0.5 parts by mass or more, and particularly preferably 1 part by mass or more, while being preferably 30 parts by mass or less, preferably 25 parts by mass or less, and particularly preferably 20 parts by mass or less.
By setting the content of the graft polymer (B) to 0.1 parts by mass or more, the impact resistance of the resin composition can be further improved. Also, by setting the content of the graft polymer (B) to 30 parts by mass or less, the decrease in the rigidity of the resin composition can be suppressed.

The ratio of polymer (C) to 100 parts by mass of polyamide resin (A) is not particularly limited, but is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, and particularly preferably 0.3 parts by mass or more, while being preferably 10 parts by mass or less, preferably 8 parts by mass or less, and particularly preferably 5 parts by mass or less.
By making the content of the polymer (C) 0.1 parts by mass or more, the heat deterioration resistance of the resin composition can be further improved, and by making the content of the polymer (C) 10 parts by mass or less, the decrease in melt fluidity of the resin composition can be suppressed.

Other additives may be added to the resin composition as long as they do not impair the effects of the present invention. Examples of such additives include fillers, heat stabilizers, antioxidants, dyes, pigments, etc.

Examples of fillers that can be used include fibrous fillers such as glass fiber, carbon fiber, alumina fiber, and ceramic fiber; whisker fillers such as calcium carbonate, zinc oxide, aluminum borate, and potassium titanate; and non-fibrous fillers such as talc, mica, clay, zeolite, glass flakes, glass beads, silica, montmorillonite, and wollastonite. Of these, glass fiber is particularly preferred.

These fillers may also be pretreated with a coupling agent such as an epoxy compound, an isocyanate compound, or an organic silane compound.

These fillers can be used alone or in combination and are selected appropriately depending on the application.

There are no particular limitations on the amount of filler used, but in general, 5 parts by mass or more and 50 parts by mass or less per 100 parts by mass of the resin composition is preferred. If the amount is 5 parts by mass or more, an improvement in rigidity is likely to be observed, and if the amount is 50 parts by mass or less, it is easy to avoid a decrease in moldability due to a significant increase in viscosity. From the viewpoint of achieving both rigidity and moldability, 10 parts by mass or more and 35 parts by mass or less is more preferred, and 15 parts by mass or less and 30 parts by mass or less is even more preferred.

As the heat stabilizer, a copper compound is preferred from the viewpoint of long-term resistance to thermal decomposition. Specific examples of copper compounds include copper chloride, copper bromide, copper iodide, copper sulfate, copper nitrate, copper phosphate, copper acetate, copper stearate, etc. From the viewpoint of the effect of long-term resistance to thermal decomposition, monovalent copper compounds are preferred.

Conventional antioxidants such as hindered phenol compounds and phosphorus compounds are used. In order to prevent volatilization and decomposition during melt kneading, those with a high melting point are preferred.

As the coloring matter or pigment, inorganic pigments include, for example, iron oxide, ultramarine, titanium oxide, carbon black, etc. Organic pigments include, for example, blue pigments of phthalocyanine or anthraquinone, red pigments of perylene or quinacridone, and yellow pigments of isoindolinone. Special pigments include fluorescent pigments, metal powder pigments, and pearl pigments. Dyes include nigrosine, perinone, and anthraquinone dyes. These coloring matter and pigments are commercially available in various grades according to the required color, and these can be used. These can be used alone or in combination of two or more. There is no particular limit to the amount of these coloring agents to be added, but in order to provide excellent appearance, it is preferable to add 0.01 to 3 parts by mass, more preferably 0.05 to 2 parts by mass, and even more preferably 0.1 to 2 parts by mass, per 100 parts by mass of the resin composition.

In addition to additives, the composition may contain flame retardants (phosphorus-based, bromine-based, silicone-based, organometallic salt-based, etc.), anti-drip agents (e.g., fluorinated polyolefin, silicone, and aramid fiber), lubricants (e.g., long-chain fatty acid metal salts such as magnesium stearate), release agents (e.g., pentaerythritol tetrastearate), nucleating agents, antistatic agents, ultraviolet absorbers, amine-based light stabilizers, plasticizers, etc.

(Method for producing resin composition)
The resin composition can be produced by mixing the polyamide resin (A), the graft polymer (B), the polymer (C), and, if necessary, additives.
The method for mixing the materials is not particularly limited and may be any known blending method, such as a method of mixing and kneading the materials using a tumbler, a V-type blender, a super mixer, a Nauta mixer, a Banbury mixer, a kneading roll, a single-screw extruder, or a twin-screw extruder.
An example of the method for producing the resin composition of the present invention is a method in which the polyamide resin (A), the graft polymer (B), and the polymer (C), and optionally additives, are mixed using a twin-screw extruder, extruded into a strand shape, and cut into pellets using a rotary cutter, etc. By this method, a pellet-shaped resin composition can be obtained.

[Molded body]
A molded article can be produced by molding the resin composition according to this embodiment.
The molded article contains the resin composition according to this embodiment.
The molding method of the resin composition is not particularly limited, but specific examples include extrusion molding, injection molding, blow molding, press molding, insert molding, suction blow molding, three-dimensional blow molding, multi-color molding, etc. The resin composition of the present invention is particularly suitable for extrusion molding, blow molding, suction blow molding, and three-dimensional blow molding because the melt viscosity of the composition is easy to control.

The molded articles can be widely used industrially as various materials in the fields of automobiles, office equipment, home appliances, electrical and electronics, lifestyle and cosmetics, medical products, etc. More specifically, they can be used as automobile parts such as intake manifolds, radiator tanks, transmission mounts, fuel tubes, air brake tubes, ducts, exhaust gas tubes, etc., electrical and electronic parts such as gears, hubs, bushes, connectors, machine parts such as bearing retainers, fans, impellers, etc., lifestyle products such as food packaging films, fishing lines, sports shoe soles, etc., medical products such as medical packs, medical catheters and pipes, etc.

The present invention will be described in more detail below with reference to Production Examples and Examples, but the present invention is not limited to these Examples. Production Examples 1 to 4 are production examples of the graft polymer (B). In addition, "parts" means "parts by mass" and "%" means "% by mass". Examples 9 to 12 are reference examples.

[Measurement of solid content]
A polymer latex having a mass w1 is dried in a hot air dryer at 180° C. for 30 minutes, and the mass w2 of the residue after drying is measured, and the solid content [%] is calculated by the following formula (E).
Solid content [%] = w2 / w1 × 100 ... (E)

[Method for measuring particle size of graft polymer (B)]
The polymer latex to be measured is diluted with deionized water to a solid content concentration of about 3% to prepare a sample, and the number average particle diameter Dn and the mass average particle diameter Dw are measured using the above-mentioned particle size distribution meter CHDF2000 manufactured by MATEC Corporation, USA, under the following conditions.
Cartridge: a dedicated capillary cartridge for particle separation (product name: C-202),
Carrier liquid: Dedicated carrier liquid (product name: 2XGR500),
Carrier liquid: neutral,
Carrier liquid flow rate: 1.4 mL/min,
Carrier fluid pressure: 4,000 psi (2,600 kPA);
Measurement temperature: 35℃,
Sample volume used: 0.1 mL.

[Method for measuring Tg of polymer]
The Tg of the polymer was evaluated by using a dynamic viscoelasticity measuring device (DMS) (Seiko Instruments Inc., DMS6100) according to the following method.
The graft polymer (B) is compression molded at 160° C. and 5 MPa for 10 minutes to prepare a test piece having a thickness of 2 mm, which is then measured in a bending mode at a frequency of 1 Hz in a temperature range of −150° C. to 180° C. The peak temperature of the obtained tan δ is taken as Tg.

[Method for measuring acid value of polymer (C)]
About 0.2 g of polymer (C) was collected in a 250 ml Erlenmeyer flask, the mass was measured, and then the polymer was dissolved in 20 ml of chloroform and titrated with a 0.1 N (normal) potassium hydroxide ethanol solution using phenolphthalein as an indicator to calculate the acid value [mg KOH/g].

[Method of measuring melting point of polymer (C)]
The melting point of the polymer (C) was evaluated by using a differential scanning calorimeter (DSC) (DSC6200, manufactured by Seiko Instruments Inc.) according to the following method.
About 10 mg of polymer (C) was placed in an aluminum sample container, heated to 200° C. at a heating rate of 10° C./min, held for 5 minutes, and then cooled to 0° C. at a heating rate of 10° C./min. The temperature was then increased again at a heating rate of 10° C./min, held for 5 minutes, and cooled at a rate of 10° C./min. The maximum point of the crystal melting peak observed at this time was taken as the melting point of polymer (C).

[Raw materials]
The raw materials used in the examples and comparative examples are shown below.
(1) Polyamide resin (A)
PA6 (Nylon 6): Manufactured by Ube Industries, Ltd., Product name: UBE Nylon 1022B
PA66 (Nylon 66): manufactured by Toyobo Co., Ltd., product name: Glamid T-662
PA66+GF (glass fiber-containing nylon 66): manufactured by Toyobo Co., Ltd., product name: Glamid T-663G30 (containing 30% glass fiber)
(2) Polymer (C)
30M: Mitsubishi Chemical Corporation, product name: Diacalna 30M (a copolymer of α-olefin and maleic anhydride containing multiple types of α-olefins having 28 to 58 carbon atoms as copolymerization components, acid value: 90 mg KOH/g, melting point 72° C.)
CE2: Clariant Chemicals, product name: Lycorb CE2 (a copolymer of α-olefin and maleic anhydride containing multiple α-olefins having 28 to 58 carbon atoms as copolymerization components, acid value: 81 mg KOH/g, melting point: 74°C)
1105A: Mitsui Chemicals, Inc., product name: Hiwax 1105A (maleic anhydride modified polyethylene, acid value: 60 mg KOH/g, melting point 104°C)
2203A: Mitsui Chemicals, Inc., product name: Hiwax 2203A (maleic anhydride modified polyethylene, acid value: 30 mg KOH/g, melting point 107°C)
U1001: Sanyo Chemical Industries, Ltd., product name: Umex 1001 (maleic anhydride modified polypropylene, acid value: 26 mg KOH/g, melting point: 142° C.)
H12: Clariant Chemicals, product name: Lycorb H12 (carboxyl group-containing oxidized polyethylene, acid value: 17 mg KOH/g, melting point: 104° C.)
VPN233: Manufactured by Emery Oleochemicals, product name: Roxiol VPN233 (polyethylene, acid value: 0 mgKOH/g, melting point: 110°C)

<Production Example 1-1> (Production of polyorganosiloxane (β-1-1))
98 parts of a cyclic organosiloxane mixture (manufactured by Shin-Etsu Silicone Co., Ltd., product name: DMC, a mixture of cyclic organosiloxanes having 3 to 6 membered rings) and 2 parts of 3-methacryloxypropylmethyldimethoxysilane (KBM-502) were mixed to obtain 100 parts of an organosiloxane mixture. An aqueous solution of 0.7 parts of sodium dodecylbenzenesulfonate (DBSNa) dissolved in 350 parts of deionized water was added to the mixture, and the mixture was stirred at 10,000 rpm for 5 minutes with a homomixer, and then passed through a homogenizer twice at a pressure of 20 MPa to obtain a stable premixed emulsion.
Next, an aqueous solution of 10 parts of dodecylbenzenesulfonic acid (DBSH) dissolved in 40 parts of deionized water was placed in a 5-liter separable flask equipped with a cooling condenser, and the aqueous solution was heated to a temperature of 80°C. The above emulsion was then continuously added over a period of 240 minutes to cause a polymerization reaction, and the mixture was cooled to 25°C. A 5% aqueous sodium hydroxide solution was added to neutralize the reaction liquid to a pH of 7.5, thereby obtaining a polyorganosiloxane latex (β-1-1).
The polyorganosiloxane latex (β-1-1) had a solid content of 18%. The number average particle diameter (Dn) of this latex measured by a capillary particle size distribution analyzer was 46 nm, the mass average particle diameter (Dw) was 75 nm, and Dw/Dn was 1.63.

<Production Example 1-2> (Production of polyorganosiloxane (β-1-2))
96 parts of a cyclic organosiloxane mixture (manufactured by Shin-Etsu Silicone Co., Ltd., product name: DMC, a mixture of cyclic organosiloxanes having 3 to 6 membered rings), 2.0 parts of tetraethoxysilane (TEOS), and 2.0 parts of 3-methacryloxypropylmethyldimethoxysilane (KBM-502) were mixed to obtain 100 parts of an organosiloxane mixture. An aqueous solution of 1.0 part of sodium dodecylbenzenesulfonate (DBSNa) dissolved in 250 parts of deionized water was added to the mixture, and the mixture was stirred at 10,000 rpm for 5 minutes with a homomixer, and then passed through a homogenizer twice at a pressure of 20 MPa to obtain a stable premixed emulsion.

Next, the mixed emulsion was placed in a 5-liter separable flask equipped with a cooling condenser, and the aqueous solution was heated to a temperature of 80° C., and then a mixture of 0.20 parts of sulfuric acid and 49.8 parts of distilled water was continuously added over a period of 3 minutes. The state of being heated to a temperature of 80° C. was maintained for 7 hours to carry out a polymerization reaction, and then the mixture was cooled to 25° C., and a 5% aqueous sodium hydroxide solution was added to neutralize the reaction liquid to a pH of 7.0, to obtain a polyorganosiloxane latex (β-1-2).
The solid content of the polyorganosiloxane latex (β-1-2) was 28% by mass. The number average particle diameter (Dn) of this latex measured by a capillary particle size distribution analyzer was 380 nm, the mass average particle diameter (Dw) was 407 nm, and Dw/Dn was 1.07.

<Production Example 2-1> (Production of Rubber-Containing Graft Polymer (B-1))
60 parts of the polyorganosiloxane latex (β-1-1) obtained in Production Example 1-1 (10 parts in terms of polymer) was collected in a 5-liter separable flask, and 160 parts of deionized water was added and mixed. Next, 69.9 parts of n-butyl acrylate (nBA), 0.1 parts of allyl methacrylate (AMA), and 0.15 parts of t-butyl hydroperoxide were added to the separable flask, and the atmosphere in the flask was replaced with nitrogen by passing a nitrogen stream through it, and the liquid temperature was raised to 50°C and stirred for 1 hour.

Next, 5 parts of deionized water containing 0.0005 parts of ferrous sulfate heptahydrate, 0.0015 parts of ethylenediaminetetraacetic acid disodium salt dihydrate, and 0.2 parts of sodium formaldehyde sulfoxylate (SFS) was added to initiate radical polymerization. The mixture was then held for 1 hour to complete the polymerization, yielding a composite rubber latex.

While maintaining the liquid temperature of this latex at 50°C, a mixture of 16.1 parts of methyl methacrylate (MMA), 0.9 parts of n-butyl acrylate (nBA), 3.0 parts of glycidyl methacrylate (GMA), and 0.05 parts of t-butyl hydroperoxide (t-BH) was added dropwise to the latex at a rate of 0.5 parts/min to carry out a graft polymerization reaction. After completion of the addition, the mixture was held at 50°C for 1 hour and then cooled to 25°C to obtain a latex of polyorganosiloxane-containing graft copolymer (B-1).

The solid content of the latex was 32% by mass, and the polymerization rate was 99.9% or more.
The number average particle diameter (Dn) measured by a capillary particle size distribution analyzer was 102 nm, the mass average particle diameter (Dw) was 107 nm, and Dw/Dn was 1.05.

Next, 630 parts of an aqueous solution with a calcium acetate concentration of 0.8% by mass was heated to 50°C, and the obtained graft copolymer latex was gradually dropped into the aqueous solution while stirring to coagulate. The obtained graft copolymer was filtered, washed, dehydrated, and then dried to obtain a powder of graft copolymer (B-1) containing epoxy groups.

The graft copolymer (B-1) had a Tg derived from the polyorganosiloxane of -118°C, a Tg derived from the poly(meth)acrylate polymer of -27°C, and a Tg derived from the graft polymer made of the vinyl monomer component (b) of 111°C.

<Production Example 2-2> (Production of Rubber-Containing Graft Polymer (B-2))
Except for changing the polyorganosiloxane latex used to the polyorganosiloxane latex (β-1-2) obtained in Production Example 1-2, the same procedure as in Production Example 2-1 (production of rubber-containing graft polymer (B-1)) was performed to obtain a latex of polyorganosiloxane-containing graft copolymer (B-2).

The solid content of the latex was 32% by mass, and the polymerization rate was 99.9% or more.
The number average particle diameter (Dn) measured by a capillary particle size distribution analyzer was 306 nm, the mass average particle diameter (Dw) was 521 nm, and Dw/Dn was 1.70.

Next, 630 parts of an aqueous solution with a calcium acetate concentration of 0.8% by mass was heated to 60°C, and the obtained graft copolymer latex was gradually dropped into the aqueous solution while stirring to coagulate it. The obtained graft copolymer was filtered, washed, dehydrated, and then dried to obtain a powder of graft copolymer (B-2) containing epoxy groups.

The graft copolymer (B-2) had a Tg derived from the polyorganosiloxane of -118°C, a Tg derived from the poly(meth)acrylate polymer of -27°C, and a Tg derived from the graft polymer made of the vinyl monomer component (b) of 112°C.

<Production Example 2-3> (Production of Rubber-Containing Graft Polymer (B-3))
Except for using the vinyl monomer component (b) in the graft polymerization in the ratio shown in Table 1, the same procedure as in Production Example 2-1 (production of rubber-containing graft polymer (B-1)) was carried out to obtain a latex of polyorganosiloxane-containing graft copolymer (B-3).

The solid content of the latex was 32% by mass, and the polymerization rate was 99.9% or more.
The number average particle diameter (Dn) measured by a capillary particle size distribution analyzer was 103 nm, the mass average particle diameter (Dw) was 107 nm, and Dw/Dn was 1.04.

Next, 630 parts of an aqueous solution with a calcium acetate concentration of 0.8% by mass was heated to 50°C, and the obtained graft copolymer latex was gradually dropped into the aqueous solution while stirring to coagulate. The obtained graft copolymer was filtered, washed, dehydrated, and then dried to obtain a powder of graft copolymer (B-3) containing epoxy groups.

The graft copolymer (B-3) had a Tg derived from the polyorganosiloxane of -115°C, a Tg derived from the poly(meth)acrylate polymer of -26°C, and a Tg derived from the graft polymer made of the vinyl monomer component (b) of 114°C.

<Production Example 2-4> (Production of Rubber-Containing Graft Polymer (B-4))
Except for the vinyl monomer component (b) used in the graft polymerization being in the ratio shown in Table 1, the same procedure as in Production Example 2-1 (production of rubber-containing graft polymer (B-1)) was carried out to obtain a latex of polyorganosiloxane-containing graft copolymer (B-4).

The solid content of the latex was 32% by mass, and the polymerization rate was 99.9% or more.
The number average particle diameter (Dn) measured by a capillary particle size distribution analyzer was 101 nm, the mass average particle diameter (Dw) was 107 nm, and Dw/Dn was 1.06.

Next, 630 parts of an aqueous solution with a calcium acetate concentration of 0.8% by mass was heated to 55°C, and the obtained graft copolymer latex was gradually dropped into the aqueous solution while stirring to coagulate. The obtained graft copolymer was filtered, washed, dehydrated, and then dried to obtain a powder of graft copolymer (B-4). Graft copolymer (B-4) does not contain epoxy groups.

The graft copolymer (B-4) had a Tg derived from the polyorganosiloxane of -118°C, a Tg derived from the poly(meth)acrylate polymer of -27°C, and a Tg derived from the graft polymer made of the vinyl monomer component (b) of 116°C.

<Examples 1 to 12 and Comparative Examples 1 to 11>
A mixture was obtained by adding the rubber-containing graft polymer (B) and the polymer (C) in the amounts shown in Tables 2 and 3 to 100 parts by mass of polyamide resin PA6. This mixture was fed to a devolatilizing twin-screw extruder (PCM-30 (trade name), manufactured by Ikegai Corporation) heated to a barrel temperature of 250° C. and kneaded to prepare pellets of each resin composition.

Each of the obtained resin composition pellets was dried at 80° C. for 10 hours and then injection molded under the following conditions to prepare test pieces for evaluation.
Injection molding machine: SE100DU (product name), manufactured by Sumitomo Heavy Industries, Ltd.
Cylinder temperature: 250°C, mold temperature: 80°C
Specimen specifications: Length 80 mm x Width 10 mm x Thickness 4 mm

[Impact resistance evaluation]
The obtained test pieces were notched with TYPE A notches according to ISO 179-1, and the Charpy impact strength was measured at 23°C and -40°C. The obtained results are shown in Tables 2 and 3. The higher the value, the better the impact resistance, which is preferable. In addition, those marked with N.B. in the tables indicate that the test pieces did not break completely in the Charpy impact test, and are preferable because they have better impact resistance than those marked with a numerical value.

[Evaluation of heat deterioration resistance]
Each resin composition pellet obtained by kneading with the twin-screw extruder was left to stand for 60 hours in an unsaturated type ultra-accelerated life tester (PC-422R7, manufactured by Hirayama Seisakusho Co., Ltd.) set at a temperature of 110°C and a humidity of 100% RH, and subjected to a wet heat treatment.

Each of the resin composition pellets obtained by kneading with the twin-screw extruder and each of the resin composition pellets after the moist heat treatment was dried at 80° C. for 10 hours, and then the melt mass flow rate (MFR) value was measured using a melt indexer (Tateyama Scientific Industry Co., Ltd., L227-42 (L220 type)) at a measurement temperature of 250° C. and a load of 2.16 kg in accordance with JIS K 7210. The obtained results are shown in Tables 2 and 3.
The smaller the difference in MFR value before and after the wet heat treatment, the better the heat deterioration resistance, which is preferable.

Comparing Examples 1 to 12 with Comparative Examples 1 to 11, it can be seen that only when the polyamide resin (A) contains both the epoxy group-containing rubber-containing graft polymer (B) and the polymer (C) containing a carboxy group or a derivative thereof, the Charpy impact strength and heat degradation resistance are excellent.

<Example 13, Comparative Examples 12 to 14>
A mixture was obtained by adding the rubber-containing graft polymer (B) and the polymer (C) in the amounts shown in Table 4 to 100 parts by mass of polyamide resin PA66. This mixture was fed to a devolatilizing twin-screw extruder (PCM-30 (product name), manufactured by Ikegai Corporation) heated to a barrel temperature of 285°C and kneaded to prepare pellets of each resin composition.

Each of the obtained resin composition pellets was dried at 80° C. for 10 hours and then injection molded under the following conditions to prepare test pieces for evaluation.
Injection molding machine: SE100DU (product name), manufactured by Sumitomo Heavy Industries, Ltd.
Cylinder temperature: 285°C, mold temperature: 80°C
Specimen specifications: Length 80 mm x Width 10 mm x Thickness 4 mm

[Impact resistance evaluation]
The obtained test pieces were notched with a TYPE A notch in accordance with ISO 179-1, and the Charpy impact strength was measured at 23° C. and −40° C. The results are shown in Table 4. Note that the higher the value, the better the impact resistance, which is preferable.

[Evaluation of heat deterioration resistance]
Each resin composition pellet obtained by kneading with the twin-screw extruder was left to stand for 60 hours in an unsaturated type ultra-accelerated life tester (PC-422R7, manufactured by Hirayama Seisakusho Co., Ltd.) set at a temperature of 110°C and a humidity of 100% RH, and subjected to a wet heat treatment.

Each of the resin composition pellets obtained by kneading with the twin-screw extruder and each of the resin composition pellets after the moist heat treatment was dried at 80° C. for 10 hours, and then the melt mass flow rate (MFR) value was measured using a melt indexer (Tateyama Scientific Industry Co., Ltd., L227-42 (L220 type)) at a measurement temperature of 285° C. and a load of 2.16 kg in accordance with JIS K 7210. The obtained results are shown in Table 4.
The smaller the difference in MFR value before and after the wet heat treatment, the better the heat deterioration resistance, which is preferable.

Comparing Example 13 with Comparative Examples 12 to 14, it can be seen that only when the polyamide resin (A) contains both the epoxy group-containing rubber-containing graft polymer (B) and the polymer (C) containing a carboxy group and/or its derivative, the Charpy impact strength and heat degradation resistance are excellent.

<Example 14, Comparative Examples 15 to 17>
Mixtures were obtained by adding the polyamide resin PA66, the glass fiber-containing polyamide resin PA66+GF, the rubber-containing graft polymer (B) and the polymer (C) in the amounts shown in Table 5. In each mixture, the polyamide resin content was 100 parts by mass and the GF content was 20 wt %.
This mixture was fed to a devolatilizing twin-screw extruder (PCM-30 (trade name), manufactured by Ikegai Corporation) heated to a barrel temperature of 285° C. and kneaded to prepare pellets of each resin composition.

Each of the obtained resin composition pellets was dried at 80° C. for 10 hours and then injection molded under the following conditions to prepare test pieces for evaluation.
Injection molding machine: SE100DU (product name), manufactured by Sumitomo Heavy Industries, Ltd.
Cylinder temperature: 285°C, mold temperature: 80°C
Specimen specifications: Length 80 mm x Width 10 mm x Thickness 4 mm

[Impact resistance evaluation]
The obtained test pieces were notched with a TYPE A notch in accordance with ISO 179-1, and the Charpy impact strength was measured at 23° C. and −40° C. The results are shown in Table 5. Note that the higher the value, the better the impact resistance, which is preferable.

[Evaluation of heat deterioration resistance]
Each resin composition pellet obtained by kneading with the twin-screw extruder was left to stand for 60 hours in an unsaturated type ultra-accelerated life tester (PC-422R7, manufactured by Hirayama Seisakusho Co., Ltd.) set at a temperature of 110°C and a humidity of 100% RH, and subjected to a wet heat treatment.

Each of the resin composition pellets obtained by kneading with the twin-screw extruder and each of the resin composition pellets after the moist heat treatment was dried at 80°C for 10 hours, and then the melt mass flow rate (MFR) value was measured using a melt indexer (Tateyama Scientific Industry Co., Ltd., L227-42 (L220 type)) in accordance with JIS K 7210 under conditions of a measurement temperature of 285°C and a load of 2.16 kg. The results are shown in Table 5.
The smaller the difference in MFR value before and after the wet heat treatment, the better the heat deterioration resistance, which is preferable.

Comparing Example 14 with Comparative Examples 15 to 17, it can be seen that only when the polyamide resin (A) contains both the epoxy group-containing rubber-containing graft polymer (B) and the polymer (C) containing a carboxy group and/or its derivative, the Charpy impact strength and heat degradation resistance are excellent.

Claims (8)

The resin composition comprises a polyamide resin (A), a rubber-containing graft polymer (B) having an epoxy group, and a polymer (C) containing a carboxy group and/or a derivative thereof , wherein the polymer (C) has a carboxy group and/or a dicarboxylic anhydride group and contains an α-olefin monomer unit having 24 or more carbon atoms . The resin composition according to claim 1, wherein the ratio of the rubber-containing graft polymer (B) to 100 parts by mass of the polyamide resin (A) is 0.1 to 30 parts by mass, and the ratio of the polymer (C) is 0.1 to 10 parts by mass. The resin composition according to claim 1 or 2, wherein the rubber-containing graft polymer (B) contains at least one of polyorganosiloxane and polyalkyl(meth)acrylate as a rubber component. The resin composition according to any one of claims 1 to 3, wherein the polymer (C) contains a dicarboxylic acid anhydride group. The resin composition according to any one of claims 1 to 4, wherein the acid value of the polymer (C) is 1 to 2500 mg KOH/g. The resin composition according to any one of claims 1 to 5, wherein the acid value of the polymer (C) is 20 to 200 mg KOH/g. The resin composition according to any one of claims 1 to 6, wherein the polymer (C) contains an α-olefin monomer unit having 24 to 80 carbon atoms. A molded article containing the resin composition according to any one of claims 1 to 7.