JP7023723B2 - Polyamide composition and molded products - Google Patents

Description

The present invention relates to polyamide compositions and molded articles.

Polyamides typified by polyamide 6 (hereinafter, may be abbreviated as "PA6") and polyamide 66 (hereinafter, may be abbreviated as "PA66") have excellent molding processability, mechanical properties, or chemical resistance. Due to its excellent properties, it is widely used as a material for various parts such as automobiles, electric and electronic products, industrial materials, industrial materials, daily use and household products.
In recent years, the environment in which polyamide is used has become harsh thermally and mechanically, and mechanical characteristics, particularly rigidity after water absorption (hereinafter, may be referred to as "water absorption rigidity") and rigidity under high temperature use (hereinafter, may be referred to as "water absorption rigidity"). Hereinafter, there is a demand for a polyamide material having improved (sometimes referred to as "heat rigidity") and having little change in physical properties when used in all environments.
Further, in order to improve productivity, a molded product using polyamide may be molded under high cycle molding conditions in which the molding temperature is raised and the mold temperature is lowered.

On the other hand, when molding is performed under high temperature conditions, there is a problem that a molded product cannot be stably obtained due to decomposition of polyamide or change in fluidity.
In particular, a polyamide having excellent surface appearance stability of a molded product is required even under the harsh molding conditions as described above.

In order to meet such demands, a polyamide made of polyamide 66/6I into which an isophthalic acid component is introduced is disclosed as a material capable of improving the surface appearance and mechanical properties of a molded product (see, for example, Patent Document 1). ). Further, as a material capable of improving mechanical properties, fluidity, surface appearance and the like, a polyamide composition composed of a polyamide 6T / 6I in which a terephthalic acid component and an isophthalic acid component are introduced is disclosed (for example, Patent Document). See a few).

Further, in order to improve mechanical properties, particularly rigidity, polyamide compositions containing carbon fibers are disclosed (see, for example, Patent Documents 4 and 5).

Japanese Unexamined Patent Publication No. 6-032980 Japanese Unexamined Patent Publication No. 2000-154316 Japanese Unexamined Patent Publication No. 11-349806 Japanese Unexamined Patent Publication No. 2013-064106 Japanese Unexamined Patent Publication No. 2015-129271

However, in the techniques disclosed in Patent Documents 1 and 3, although the rigidity under normal use conditions is improved, there is room for improvement in water absorption rigidity and thermal rigidity.
Further, the polyamide manufactured by the manufacturing technique disclosed in Patent Document 2 is high, although the rigidity after water absorption, the rigidity under high temperature use and the surface appearance of the molded product under general molding conditions are improved. Under harsh molding conditions such as cycle molding, there is a problem that the surface appearance and stability of the molded product are deteriorated.

As described above, in the prior art, a polyamide copolymer having excellent water absorption rigidity and thermal rigidity and having little change in physical properties when used in all environments is not yet known. In addition, it is difficult to suppress the decrease in rigidity after water absorption and under high temperature use while maintaining the balance of mechanical strength and rigidity, which is a characteristic of polyamide copolymers, and it is difficult to suppress the decrease in rigidity after water absorption, and the polyamide copolymer weight having such physical properties. There is a demand for compositions and molded products containing coalesced or polyamides.

Further, in the techniques disclosed in Patent Documents 4 and 5, although the rigidity is greatly improved by containing carbon fiber, there are problems in the amount of chips generated during extrusion processing and the pellet shape. Further, particularly in the polyamide composition containing a high concentration of carbon fibers, it is also a problem that the appearance of the molded piece is deteriorated.

INDUSTRIAL APPLICABILITY The present invention has been made in view of the above circumstances, and provides a polyamide composition capable of obtaining a molded product having an excellent pellet shape, a reduced amount of chips generated, and an excellent surface appearance. Further, a molded product using the above-mentioned polyamide composition and having an excellent surface appearance is provided.

That is, the present invention includes the following aspects.
The polyamide composition according to the first aspect of the present invention is a polyamide composition containing (A) a crystalline polyamide, (B) an amorphous semi-aromatic polyamide, and (C) a carbon fiber. The (B) amorphous semi-aromatic polyamide contains 75 mol% or more of an isophthalic acid unit in the total dicarboxylic acid units constituting the (B) amorphous semi-aromatic polyamide, and the (B) non-crystal. Among all the diamine units constituting the crystalline semi-aromatic polyamide, 50 mol% or more of the diamine units having 4 or more and 10 or less carbon atoms are contained, and the molecular weight distribution Mw (B) of the (B) amorphous semi-aromatic polyamide is described above. Mn (B) is 2.1 or less .

In the polyamide composition according to the first aspect, the tan δ peak temperature may be 90 ° C. or higher.

In the polyamide composition according to the first aspect, the content of the carbon fiber (C) in the polyamide composition may be 30% by mass or more and 65% by mass or less.

In the polyamide composition according to the first aspect, the (A) crystalline polyamide is polyamide 4 (poly α-pyrrolidone), polyamide 6 (polycaproamide), polyamide 11 (polyundecaneamide), polyamide 12 (polydodecane). Amid), Polyamide 46 (Polytetramethylene adipamide), Polyamide 56 (Polypentamethylene adipamide), Polyamide 66 (Polyhexamethylene adipamide), Polyamide 610 (Polyhexamethylene sebacamide), Polyamide 612 ( Polyhexamethylene dodecamide), polyamide 6T (polyhexamethylene terephthalamide), polyamide 9T (polynonane methylene terephthalamide), and one or more selected from the group consisting of copolymerized polyamides containing these as constituents. May be good.

In the polyamide composition according to the first aspect, the content of the (B) amorphous polyamide in 100 parts by mass of the total amount of the (A) crystalline polyamide and the (B) amorphous semi-aromatic polyamide. May be 10 parts by mass or more and 50 parts by mass or less.

In the polyamide composition according to the first aspect, the content mass of the (B) amorphous semi-aromatic polyamide and the (C) carbon fiber may satisfy the relationship of the following formula (1).

In the polyamide composition according to the first aspect, the weight average molecular weight Mw of the polyamide composition may be 15,000 or more and 35,000 or less.

In the (B) amorphous semi-aromatic polyamide, the content of the isophthalic acid in the dicarboxylic acid unit may be 100 mol%.

In the polyamide composition according to the first aspect, the (B) amorphous semi-aromatic polyamide may be polyamide 6I.

The molded product according to the second aspect of the present invention is formed by molding the polyamide composition according to the first aspect.

The polyamide composition of the above aspect has an excellent pellet shape, a reduced amount of chips generated, and a molded product having an excellent surface appearance can be obtained. The molded product of the above aspect has an excellent surface appearance.

≪Polyamide composition≫
The polyamide composition of the present embodiment contains (A) crystalline polyamide, (B) amorphous semi-aromatic polyamide, and (C) carbon fiber. Further, the (B) amorphous semi-aromatic polyamide contains 75 mol% or more of isophthalic acid units in the total dicarboxylic acid units constituting the (B) amorphous semi-aromatic polyamide, and the above (B). ) Among all diamine units constituting the amorphous semi-aromatic polyamide, 50 mol% or more of diamine units having 4 or more and 10 or less carbon atoms are contained.

In the present specification, "polyamide" means a polymer having an amide (-NHCO-) bond in the main chain.

The polyamide composition of the present embodiment contains (A) crystalline polyamide, B) amorphous semi-aromatic polyamide and (C) carbon fiber having the above-mentioned composition, while maintaining good water absorption rigidity and thermal rigidity. , The shape of the pellet is excellent, and the amount of chips generated can be reduced. Further, by using the polyamide composition of the present embodiment, a molded product having an excellent surface appearance can be obtained.
The details of each component contained in the polyamide composition of the present embodiment will be described below.

<Polyamide>
The polyamide composition of the present embodiment contains (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide as a polyamide component. The details of each polyamide component will be described below.

[(A) Crystalline polyamide]
As used herein, the term "crystalline polyamide" is a polyamide having a heat of fusion of crystals of 4 J / g or more when measured at 20 ° C./min by a differential scanning calorimeter. The crystalline polyamide is not limited to the following, but is, for example, (A) a polyamide obtained by ring-opening polymerization of lactam, (Ab) a polyamide obtained by self-condensation of ω-aminocarboxylic acid, (A-). c) Polyamides obtained by condensing diamine and dicarboxylic acid, and copolymers thereof and the like can be mentioned. As the crystalline polyamide, one type may be used alone, or two or more types may be used in combination.

(A) The lactam used for producing the polyamide is not limited to the following, and examples thereof include pyrrolidone, caprolactam, undecalactam, and dodecalactam.
The ω-aminocarboxylic acid used in the production of the (Ab) polyamide is not limited to the following, and examples thereof include ω-amino fatty acid, which is a ring-opening compound of lactam with water.
Further, as the lactam or the ω-aminocarboxylic acid, two or more kinds of monomers may be used in combination and condensed.

The diamine (monomer) used in the production of (Ac) polyamide is not limited to the following, but is, for example, a linear aliphatic diamine, a branched chain aliphatic diamine, an alicyclic diamine, and an aroma. Examples include family diamines.
Examples of the linear aliphatic diamine include, but are not limited to, hexamethylenediamine and pentamethylenediamine.
The branched-chain aliphatic diamine is not limited to the following, and examples thereof include 2-methylpentanediamine and 2-ethylhexamethylenediamine.
The alicyclic diamine is not limited to the following, and examples thereof include cyclohexanediamine, cyclopentanediamine, and cyclooctanediamine.
The aromatic diamine is not limited to the following, and examples thereof include p-phenylenediamine and m-phenylenediamine.
Examples of the dicarboxylic acid (monomer) used in the production of (Ac) polyamide include, but are not limited to, aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, and aromatic dicarboxylic acids.
The aliphatic dicarboxylic acid is not limited to the following, and examples thereof include adipic acid, pimelic acid, and sebacic acid.
The alicyclic dicarboxylic acid is not limited to the following, and examples thereof include cyclohexanedicarboxylic acid.
The aromatic dicarboxylic acid is not limited to the following, and examples thereof include phthalic acid and isophthalic acid.
The above-mentioned diamine and dicarboxylic acid as monomers may be condensed alone or in combination of two or more.

The crystalline polyamide (A) may further contain a unit derived from a trivalent or higher valent carboxylic acid such as trimellitic acid, trimesic acid, and pyromellitic acid, if necessary. As the trivalent or higher-valent polyvalent carboxylic acid, only one type may be used alone, or two or more types may be used in combination.

Specific examples of the (A) crystalline polyamide contained in the polyamide composition of the present embodiment include polyamide 4 (poly α-pyrrolidone), polyamide 6 (polycaproamide), polyamide 11 (polyundecaneamide), and polyamide. 12 (Polydodecaneamide), Polyamide 46 (Polytetramethylene adipamide), Polyamide 56 (Polypentamethylene adipamide), Polyamide 66 (Polyhexamethylene adipamide), Polyamide 610 (Polyhexamethylene sebacamide) , Polyamide 612 (polyhexamethylene dodecamide), polyamide 6T (polyhexamethylene terephthalamide), polyamide 9T (polynonane methylene terephthalamide), and copolymerized polyamides containing these as constituents.
Among them, as the (A) crystalline polyamide, polyamide 66 (PA66), polyamide 46 (PA46), or polyamide 610 (PA610) is preferable. PA66 is a suitable material for automobile parts because it has excellent heat resistance, moldability, and toughness. Further, long-chain aliphatic polyamides such as PA610 are excellent in chemical resistance and are preferable.

The content of the (A) crystalline polyamide in the polyamide composition of the present embodiment can be, for example, 50% by mass or more and 99% by mass or less with respect to the total mass of all the resins contained in the polyamide composition. For example, it can be 60% by mass or more and 95% by mass or less, and can be, for example, 70% by mass or more and 85% by mass or less.

[(B) Amorphous semi-aromatic polyamide]
The (B) amorphous semi-aromatic polyamide contained in the polyamide composition of the present embodiment is a polyamide containing a diamine unit and a dicarboxylic acid unit. (B) The amorphous semi-aromatic polyamide contains 75 mol% or more of isophthalic acid units with respect to all the dicarboxylic acid units constituting (B) the amorphous semi-aromatic polyamide (BA) dicarboxylic acid units. And (B) a polyamide containing 50 mol% or more of diamine units having 4 or more and 10 or less carbon atoms with respect to all the diamine units constituting the amorphous semi-aromatic polyamide (B). It is preferable to have.
At this time, the total amount of (B) isophthalic acid units in the amorphous semi-aromatic polyamide and diamine units having 4 or more and 10 or less carbon atoms is included in all the constituent units of (B) the amorphous semi-aromatic polyamide. On the other hand, 80 mol% or more and 100 mol% or less are preferable, 90 mol% or more and 100 mol% or less are more preferable, and 100 mol% is further preferable.
In the present specification, (B) the ratio of a predetermined monomer unit constituting the amorphous semi-aromatic polyamide can be measured by nuclear magnetic resonance spectroscopy (NMR) or the like.

((BA) Dicarboxylic acid unit)
The (BA) dicarboxylic acid unit can contain 75 mol% or more of isophthalic acid, preferably 80 mol% or more and 100 mol% or less, based on the total number of moles of the (BA) dicarboxylic acid. , 90 mol% or more and 100 mol% or less is more preferable, and 100 mol% is more preferable.
(BA) A polyamide composition in which the ratio of the isophthalic acid unit to the dicarboxylic acid unit is at least the above lower limit value, thereby simultaneously satisfying mechanical properties, particularly water absorption rigidity, thermal rigidity, fluidity, surface appearance and the like. Can be obtained.

The (BA) dicarboxylic acid unit may contain an aromatic dicarboxylic acid unit, an aliphatic dicarboxylic acid unit, and an alicyclic dicarboxylic acid unit other than the isophthalic acid unit.

(1) Aromatic dicarboxylic acid unit The aromatic dicarboxylic acid constituting an aromatic dicarboxylic acid unit other than the isophthalic acid unit is not limited to the following, but is, for example, an aromatic group such as a phenyl group or a naphthyl group. Dicarboxylic acid having. The aromatic group of the aromatic dicarboxylic acid may be unsubstituted or may have a substituent.
The substituent is not particularly limited, but is, for example, an alkyl group having 1 or more and 4 or less carbon atoms, an aryl group having 6 or more and 10 or less carbon atoms, an arylalkyl group having 7 or more and 10 or less carbon atoms, a halogen group, and 1 carbon group. Examples thereof include a silyl group of 6 or less, a sulfonic acid group and a salt thereof (sodium salt, etc.).

The alkyl group having 1 or more and 4 or less carbon atoms is not limited to the following, but for example, 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. And so on.

Examples of the aryl group having 6 or more and 10 or less carbon atoms include, but are not limited to, a phenyl group, a tolyl group, a xsilyl group, a naphthyl group and the like.

Examples of the arylalkyl group having 7 or more and 10 or less carbon atoms include, but are not limited to, a benzyl group and the like.

Examples of the halogen group include, but are not limited to, a fluoro group, a chloro group, a bromo group, an iodine group and the like.

The silyl group having 1 or more and 6 or less carbon atoms is not limited to the following, and examples thereof include a trimethylsilyl group and a tert-butyldimethylsilyl group.

Among them, as the aromatic dicarboxylic acid constituting the aromatic dicarboxylic acid unit other than the isophthalic acid unit, an aromatic dicarboxylic acid having 8 or more and 20 or less carbon atoms substituted with an unsubstituted or predetermined substituent is preferable.

Specific examples of the aromatic dicarboxylic acid having 8 or more and 20 or less carbon atoms substituted with an unsubstituted or predetermined substituent are not limited to the following, but for example, terephthalic acid, naphthalenedicarboxylic acid, and 2-chloro. Examples thereof include terephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodiumsulfoisophthalic acid and the like.
As the aromatic dicarboxylic acid constituting the aromatic dicarboxylic acid unit, only one kind may be used alone, or two or more kinds may be used in combination.

(2) Acidic Dicarboxylic Acid Unit Examples of the aliphatic dicarboxylic acid constituting the aliphatic dicarboxylic acid unit include linear or branched saturated aliphatic dicarboxylic acids having 3 or more and 20 or less carbon atoms.
The linear saturated aliphatic dicarboxylic acid having 3 or more and 20 or less carbon atoms is not limited to the following, and is, for example, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, and azelaic acid. , Sevacinic acid, dodecanedioic acid, tetradecanedioic acid, hexadecanedioic acid, octadecanedioic acid, eicosandioic acid, diglycolic acid and the like.
The branched saturated aliphatic dicarboxylic acid having 3 or more and 20 or less carbon atoms is not limited to the following, and for example, dimethylmalonic acid, 2,2-dimethylsuccinic acid, 2,3-dimethylglutaric acid, and the like. Examples thereof include 2,2-diethylsuccinic acid, 2,3-diethylglutaric acid, 2,2-dimethylglutaric acid, 2-methyladipic acid, and trimethyladipic acid.

(3) Alicyclic dicarboxylic acid unit The alicyclic dicarboxylic acid constituting the alicyclic dicarboxylic acid unit (hereinafter, may be referred to as “alicyclic dicarboxylic acid unit”) is not limited to the following. However, for example, an alicyclic dicarboxylic acid having an alicyclic structure having 3 or more and 10 or less carbon atoms can be mentioned. Among them, as the alicyclic dicarboxylic acid, an alicyclic dicarboxylic acid having an alicyclic structure having 5 or more and 10 or less carbon atoms is preferable.
Examples of such an alicyclic dicarboxylic acid include, but are not limited to, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid and the like. Will be. Among them, 1,4-cyclohexanedicarboxylic acid is preferable as the alicyclic dicarboxylic acid.
As the alicyclic dicarboxylic acid constituting the alicyclic dicarboxylic acid unit, only one kind may be used alone, or two or more kinds may be used in combination.

The alicyclic group of the alicyclic dicarboxylic acid may be unsubstituted or may have a substituent. Examples of the substituent include an alkyl group having 1 or more carbon atoms and 4 or less carbon atoms. Examples of the alkyl group having 1 or more and 4 or less carbon atoms include those similar to those exemplified in the above-mentioned "aromatic dicarboxylic acid unit".

The dicarboxylic acid unit other than the isophthalic acid unit preferably contains an aromatic dicarboxylic acid unit, and more preferably contains an aromatic dicarboxylic acid having 6 or more carbon atoms.
By using such a dicarboxylic acid, the mechanical properties of the polyamide composition, particularly water absorption rigidity, thermal rigidity, fluidity, surface appearance and the like tend to be more excellent.

(B) In the amorphous semi-aromatic polyamide, the dicarboxylic acid constituting the (BA) dicarboxylic acid unit is not limited to the compound described as the dicarboxylic acid, but is a compound equivalent to the dicarboxylic acid. May be.
The term "compound equivalent to a dicarboxylic acid" as used herein refers to a compound having a dicarboxylic acid structure similar to that of the dicarboxylic acid derived from the dicarboxylic acid. Examples of such a compound include, but are not limited to, an anhydride of a dicarboxylic acid, a halide of a dicarboxylic acid, and the like.

Further, the (B) amorphous semi-aromatic polyamide may further contain a unit derived from a trivalent or higher-valent polyvalent carboxylic acid, if necessary.
Examples of the trivalent or higher-valent polyvalent carboxylic acid include trimellitic acid, trimesic acid, and pyromellitic acid. As for these trivalent or higher-valent polyvalent carboxylic acids, only one kind may be used alone, or two or more kinds may be used in combination.

((B-b) diamine unit)
The (B) diamine unit constituting the (B) amorphous semi-aromatic polyamide preferably contains a diamine unit having 4 or more and 10 or less carbon atoms, and is a linear saturated fat having 4 or more and 10 or less carbon atoms. Group diamine units are more preferable, linear saturated aliphatic diamine units having 6 or more carbon atoms and 10 or less carbon atoms are further preferable, and hexamethylene diamine units are particularly preferable.
By using such a diamine, the polyamide composition tends to be excellent in mechanical properties, particularly water absorption rigidity, rigidity under high temperature use (heat rigidity), fluidity, surface appearance and the like.
At this time, the (B) amorphous semi-aromatic polyamide has, as the (B-b) diamine unit, a diamine unit having 4 or more and 10 or less carbon atoms with respect to the total number of moles of the (B-b) diamine unit. Can be contained in an amount of 50 mol% or more.

Further, the diamine other than the diamine having 4 or more and 10 or less carbon atoms constituting the (B) amorphous semi-aromatic polyamide is not limited to the following, but is not limited to, for example, an aliphatic diamine unit or an alicyclic diamine. Units, aromatic diamine units and the like can be mentioned.

(1) Aliphatic Diamine Unit Examples of the aliphatic diamine constituting the aliphatic diamine unit include linear saturated aliphatic diamine having 4 or more and 20 or less carbon atoms.
The linear saturated aliphatic diamine having 4 or more and 20 or less carbon atoms is not limited to the following, and for example, ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, etc. Examples thereof include octamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, and tridecamethylenediamine.

(2) Alicyclic diamine unit The alicyclic diamine constituting the alicyclic diamine unit (hereinafter, may be referred to as “alicyclic diamine”) is not limited to the following, but is not limited to the following, for example. Examples thereof include 1,4-cyclohexanediamine, 1,3-cyclohexanediamine and 1,3-cyclopentanediamine.

(3) Aromatic diamine unit The aromatic diamine constituting the aromatic diamine unit is not limited to the following as long as it is a diamine containing an aromatic. Specific examples of the aromatic diamine include metaxylylenediamine and the like.

As the diamine constituting each of these diamine units, only one type may be used alone, or two or more types may be used in combination.

The (B) amorphous semi-aromatic polyamide contained in the polyamide composition of the present embodiment is preferably polyamide 6I (polyhexamethylene isophthalamide), 9I, or 10I, and more preferably polyamide 6I.

The amorphous semi-aromatic polyamide (B) may further contain a trivalent or higher polyvalent aliphatic amine, if necessary. Examples of the trivalent or higher-valent polyphatic amine include bishexamethylenetriamine and the like. The trivalent or higher polyvalent aliphatic amine may be used alone or in combination of two or more.

The content of (B) amorphous semi-aromatic polyamide in the polyamide composition of the present embodiment is 5.0% by mass or more and 45.0% by mass with respect to 100% by mass of the total resin contained in the polyamide composition. It can be as follows, preferably 10.0% by mass or more and 42.5% by mass or less, more preferably 15.0% by mass or more and 40.0% by mass or less, and 20.0% by mass or more and 37.5% by mass or less. Is more preferable, 22.5% by mass or more and 35.0% by mass or less is particularly preferable, and 22.5% by mass or more and 30.0% by mass or less is most preferable. (B) By setting the content of the amorphous semi-aromatic polyamide in the above range, a polyamide composition having excellent mechanical properties, particularly water absorption rigidity, thermal rigidity, fluidity, surface appearance and the like can be obtained.

[End sealant]
The ends of the polyamide ((A) crystalline polyamide and (B) amorphous semi-aromatic polyamide) contained in the polyamide composition of the present embodiment may be end-sealed with a known end-sealing agent.
Such a terminal encapsulant can also be used as a molecular weight modifier when producing a polyamide from the above dicarboxylic acid, the above diamine, and, if necessary, at least one of the above lactam and the above aminocarboxylic acid. Can be added.

Examples of the terminal encapsulant include, but are not limited to, monocarboxylic acid, monoamine, acid anhydride, monoisocyanate, monoacid halide, monoesters, and monoalcohols. The acid anhydride is not limited to the following, and examples thereof include phthalic anhydride and the like. These terminal encapsulants may be used alone or in combination of two or more.
Among them, monocarboxylic acid or monoamine is preferable as the terminal encapsulant. Since the ends of the polyamide are sealed with an end sealant, the polyamide composition tends to have better thermal stability.

The monocarboxylic acid that can be used as the terminal encapsulant may be any acid that has reactivity with an amino group that can be present at the terminal 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.
The aliphatic monocarboxylic acid is not limited to, but is not limited to, for example, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristyl acid, palmitic acid, and the like. Examples thereof include stearic acid, pivalic acid and isobutyl acid.
Examples of the alicyclic monocarboxylic acid include, but are not limited to, cyclohexanecarboxylic acid.
Examples of the aromatic monocarboxylic acid include, but are not limited to, benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, phenylacetic acid and the like.
These monocarboxylic acids may be used alone or in combination of two or more.

The monoamine that can be used as the terminal encapsulant may be any monoamine that has reactivity with a carboxy group that may be present at the terminal of the polyamide. Specific examples of the monoamine include, but are not limited to, aliphatic monoamines, alicyclic monoamines, aromatic monoamines, and the like.
The aliphatic amine is not limited to, but is not limited to, for example, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, and dibutylamine. And so on.
Examples of the alicyclic amine include, but are not limited to, cyclohexylamine and dicyclohexylamine.
The aromatic amine is not limited to the following, and examples thereof include aniline, toluidine, diphenylamine, and naphthylamine.
These monoamines may be used alone or in combination of two or more.

Polyamide compositions containing polyamides terminally sealed with an end sealant tend to be superior in heat resistance, fluidity, toughness, low water absorption and rigidity.

[Polyamide manufacturing method]
When producing the polyamide, the amount of the dicarboxylic acid added and the amount of the diamine added are preferably close to the same molar amount. Considering the amount of diamine escaping to the outside of the reaction system during the polymerization reaction in terms of molar ratio, the molar amount of the entire diamine is preferably 0.9 or more and 1.2 or less with respect to the molar amount of 1 of the total dicarboxylic acid. , 0.95 or more and 1.1 or less is preferable, and 0.98 or more and 1.05 or less is more preferable.
The method for producing a polyamide is not limited to the following, but for example, a dicarboxylic acid constituting a dicarboxylic acid unit, a diamine constituting a diamine unit, and if necessary, lactam and amino constituting a lactam unit. It comprises a step of polymerizing at least one of the aminocarboxylic acids constituting the carboxylic acid unit to obtain a polymer.
Further, it is preferable that the method for producing a polyamide further includes a step of increasing the degree of polymerization of the polyamide.
Further, if necessary, a sealing step of sealing the end of the obtained polymer with an end-sealing agent may be included.

Specific examples of the method for producing the polyamide include various methods as illustrated in 1) to 4) below.
1) A method of heating an aqueous solution of a dicarboxylic acid-diamine salt or a mixture of a dicarboxylic acid and a diamine, or a suspension of these waters to polymerize while maintaining the molten state (hereinafter referred to as "heat melt polymerization method"). May be referred to).
2) A method of increasing the degree of polymerization of a polyamide obtained by a hot melt polymerization method while maintaining a solid state at a temperature below the melting point (hereinafter, may be referred to as "hot melt polymerization / solid phase polymerization method").
3) A method of polymerizing a dicarboxylic acid-diamine salt or a mixture of a dicarboxylic acid and a diamine while maintaining a solid state (hereinafter, may be referred to as a "solid phase polymerization method").
4) A method of polymerizing using a dicarboxylic acid halide component and a diamine component equivalent to the dicarboxylic acid (hereinafter, may be referred to as "solution method").
Among them, as a specific method for producing polyamide, a production method including a thermal melt polymerization method is preferable. Further, when the polyamide is produced by the thermal melt polymerization method, it is preferable to maintain the molten state until the polymerization is completed. Examples of the method for maintaining the molten state include a method for producing under polymerization conditions suitable for the composition of the polyamide. Examples of the polymerization conditions include the following conditions. First, the polymerization pressure in the thermal melt polymerization method is controlled to 14 kg / cm ² or more and 25 kg / cm ² or less (gauge pressure), and heating is continued. Then, the pressure in the tank is reduced to atmospheric pressure (gauge pressure is 0 kg / cm ² ) for 30 minutes or more to obtain a polyamide having a desired composition.

In the method for producing a polyamide, the polymerization form is not particularly limited, and may be a batch type or a continuous type.
The polymerization apparatus used for producing the polyamide is not particularly limited, and known apparatus can be used, for example, an autoclave type reactor, a tumbler type reactor, an extruder type reactor such as a kneader, and the like. Can be mentioned.

Hereinafter, as a method for producing a polyamide, a method for producing a polyamide by a batch-type thermal melt polymerization method will be specifically shown, but the method for producing a polyamide is not limited to this.
First, an aqueous solution containing about 40% by mass or more and 60% by mass or less of a raw material component of polyamide (dicarboxylic acid, diamine, and, if necessary, at least one of lactam and aminocarboxylic acid) is at 110 ° C. or higher and 180. A concentrated solution is obtained by concentrating to about 65% by mass or more and 90% by mass or less in a concentrating tank operated at a temperature of ° C. or lower and a pressure of about 0.035 MPa or more and 0.6 MPa or less (gauge pressure).
Then, the obtained concentrated solution is transferred to an autoclave, and heating is continued until the pressure in the autoclave becomes about 1.2 MPa or more and 2.2 MPa or less (gauge pressure).
After that, in the autoclave, the pressure was maintained at about 1.2 MPa or more and 2.2 MPa or less (gauge pressure) while removing at least one of the water and gas components, and when the temperature reached about 220 ° C. or more and 260 ° C. or less, The pressure is reduced to atmospheric pressure (gauge pressure is 0 MPa).
By reducing the pressure in the autoclave to atmospheric pressure and then reducing the pressure as necessary, water produced as a by-product can be effectively removed.
Then, the autoclave is pressurized with an inert gas such as nitrogen, and the polyamide melt is extruded from the autoclave as a strand. The extruded strands are cooled and cut to obtain polyamide pellets.

[Polyamide polymer terminal]
The polymer terminal of the polyamide contained in the polyamide composition of the present embodiment is not particularly limited, but can be classified and defined as follows.
That is, 1) amino terminal, 2) carboxy terminal, 3) terminal by encapsulant, and 4) other terminal.
1) The amino terminus is a polymer terminus having an amino group (-NH ₂ groups) and is derived from the diamine unit of the raw material.
2) The carboxy terminal is a polymer terminal having a carboxy group (-COOH group) and is derived from the raw material dicarboxylic acid.
3) The end by the encapsulant is the end formed when the encapsulant is added at the time of polymerization. Examples of the encapsulant include the above-mentioned terminal encapsulant.
4) The other terminals are polymer ends that are not classified into 1) to 3) described above. Specific examples of the other terminal include a terminal produced by a decarboxylation reaction of an amino terminal, a terminal produced by a decarboxylation reaction from a carboxy terminal, and the like.

[(A) Characteristics of crystalline polyamide]
(A) The molecular weight, melting point Tm2 and crystallization enthalpy ΔH of the crystalline polyamide can be measured by the methods described in Examples described later.
Further, the tan δ peak temperature of (A) crystalline polyamide can be measured by the method shown below.

((A) Weight average molecular weight Mw (A) of crystalline polyamide)
(A) As an index of the molecular weight of the crystalline polyamide, a weight average molecular weight Mw (A) can be used. The weight average molecular weight Mw (A) of the crystalline polyamide is preferably 10,000 or more and 50,000 or less, more preferably 15,000 or more and 45,000 or less, further preferably 20,000 or more and 40,000 or less, and particularly preferably 25,000 or more and 35,000 or less.
When the weight average molecular weight Mw (A) is in the above range, a polyamide composition excellent in mechanical properties, particularly water absorption rigidity, thermal rigidity, fluidity, surface appearance and the like can be obtained.
The weight average molecular weight Mw (A) can be measured by using gel permeation chromatography (GPC) as described in the following examples.

((A) Molecular weight distribution of crystalline polyamide Mw (A) / Mn (A))
(A) The molecular weight distribution of the crystalline polyamide uses the weight average molecular weight Mw (A) / number average molecular weight Mn (A) as an index.
(A) The Mw (A) / Mn (A) of the crystalline polyamide can be 1.0 or more, preferably 1.8 or more and 2.2 or less, and more preferably 1.9 or more and 2.1 or less.
When Mw (A) / Mn (A) is in the above range, a polyamide composition having excellent fluidity, surface appearance and the like can be obtained.
(A) As a method for controlling Mw / Mn of the crystalline polyamide within the above range, for example, a known polycondensation catalyst such as phosphoric acid or sodium hypophosphite is used as an additive during thermal melt polymerization of the polyamide. Examples thereof include a method of adding and a method of controlling polymerization conditions such as heating conditions and depressurizing conditions.
(A) Mw (A) / Mn (A) of the crystalline polyamide is a weight average molecular weight Mw (A) and a number average molecular weight Mn (A) obtained by using GPC as described in the following examples. Can be calculated using.

((A) Melting point Tm2 of crystalline polyamide)
(A) The lower limit of the melting point Tm2 of the crystalline polyamide is preferably 220 ° C., more preferably 230 ° C., and even more preferably 240 ° C.
On the other hand, the upper limit of the melting point Tm2 of the (A) crystalline polyamide is preferably 300 ° C., more preferably 290 ° C., still more preferably 280 ° C., and particularly preferably 270 ° C.
That is, the melting point Tm2 of (A) crystalline polyamide is preferably 220 ° C. or higher and 300 ° C. or lower, more preferably 230 ° C. or higher and 290 ° C. or lower, further preferably 240 ° C. or higher and 280 ° C. or lower, and particularly preferably 240 ° C. or higher and 270 ° C. or lower. preferable.
(A) When the melting point Tm2 of the crystalline polyamide is at least the above lower limit value, the thermal rigidity of the molded product obtained from the polyamide composition tends to be more excellent.
Further, when the melting point Tm2 of (A) crystalline polyamide is not more than the above upper limit value, there is a tendency that thermal decomposition of the polyamide composition in melt processing such as extrusion and molding can be further suppressed.

((A) Crystallization enthalpy ΔH of crystalline polyamide)
(A) The lower limit of the crystallization enthalpy ΔH of the crystalline polyamide can be 4J / g, 20J / g, or 30J from the viewpoint of mechanical properties, particularly water absorption rigidity and thermal rigidity. It can be / g, it can be 40 J / g, it can be 50 J / g, it can be 60 J / g. On the other hand, the upper limit of the crystallization enthalpy ΔH of (A) crystalline polyamide is not particularly limited, and the higher the value, the more preferable.
Examples of the device for measuring the melting point Tm2 and the crystallization enthalpy ΔH of the crystalline polyamide (A) include Diamond-DSC manufactured by PERKIN-ELMER.

((A) Tanδ peak temperature of crystalline polyamide)
(A) The tan δ peak temperature of the crystalline polyamide can be 40 ° C. or higher, 50 ° C. or higher and 110 ° C. or lower, 60 ° C. or higher and 100 ° C. or lower, and 70 ° C. or higher and 95 ° C. or lower. It can be 80 ° C. or higher and 90 ° C. or lower.
(A) When the tan δ peak temperature of the crystalline polyamide is at least the above lower limit value, it tends to be possible to obtain a polyamide composition having better water absorption rigidity and thermal rigidity.
(A) The tan δ peak temperature of the crystalline polyamide can be measured by using, for example, a viscoelasticity measuring and analyzing device (manufactured by Rheology: DVE-V4).

[(B) Characteristics of amorphous semi-aromatic polyamide]
(B) The molecular weight of the amorphous semi-aromatic polyamide can be measured by the method described in Examples described later.
Further, (B) the melting point Tm2 of the amorphous semi-aromatic polyamide, the crystallization enthalpy ΔH, the tan δ peak temperature, the amino terminal amount, and the carbonic acid terminal amount can be measured by the methods shown below.

((B) Weight average molecular weight Mw (B) of amorphous semi-aromatic polyamide)
As an index of the molecular weight of (B) amorphous semi-aromatic polyamide, (B) weight average molecular weight (Mw (B)) of (B) amorphous semi-aromatic polyamide can be used.
(B) The weight average molecular weight (Mw (B)) of the amorphous semi-aromatic polyamide is preferably 10,000 or more and 25,000 or less, more preferably 13,000 or more and 24,000 or less, further preferably 15,000 or more and 23,000 or less, and 18,000 or more and 22,000 or less. It is particularly preferable, and most preferably 19000 or more and 21000 or less.
(B) Since the weight average molecular weight (Mw (B)) of the amorphous semi-aromatic polyamide is in the above range, the polyamide composition is excellent in mechanical properties, particularly water absorption rigidity, thermal rigidity, fluidity, surface appearance and the like. You get things. The weight average molecular weight (Mw (B)) of (B) amorphous semi-aromatic polyamide can be measured by using GPC as described in Examples described later.

((B) Molecular weight distribution of amorphous semi-aromatic polyamide Mw (B) / Mn (B))
The molecular weight distribution of (B) amorphous semi-aromatic polyamide is (B) weight average molecular weight of (B) amorphous semi-aromatic polyamide (Mw (B)) / (B) number average molecular weight of (B) amorphous semi-aromatic polyamide. (Mn (B)) is used as an index.
Mw (B) / Mn (B) can be 2.4 or less, preferably 1.0 or more and 2.4 or less, more preferably 1.7 or more and 2.4 or less, and 1.8 or more and 2.3. The following is more preferable, 1.9 or more and 2.2 or less are particularly preferable, and 1.9 or more and 2.1 or less are most preferable.
When Mw (B) / Mn (B) is in the above range, a polyamide composition having excellent fluidity, surface appearance and the like can be obtained.

Examples of the method for controlling Mw (B) / Mn (B) within the above range include the methods shown in 1) or 2) below.
1) A method of adding a known polycondensation catalyst such as phosphoric acid or sodium hypophosphite as an additive during thermal melt polymerization of polyamide.
2) In addition to the method of 1) above, a method of controlling polymerization conditions such as heating conditions and depressurizing conditions to complete the polycondensation reaction at the lowest possible temperature and in a short time.

In particular, since (B) amorphous semi-aromatic polyamide does not have a melting point, the reaction temperature can be lowered to control Mw (B) / Mn (B) within the above range.
Further, when the aromatic compound unit is contained in the molecular structure of the polyamide, the molecular weight distribution (Mw / Mn) tends to increase as the molecular weight increases. (B) When the molecular weight distribution (Mw (B) / Mn (B)) of the amorphous semi-aromatic polyamide is within the above range, the proportion of polyamide molecules having a three-dimensional structure of the molecule can be reduced. , It is possible to more preferably prevent the three-dimensional structuring of molecules during high-temperature processing, and it is possible to maintain better fluidity. Thereby, the surface appearance of the molded product obtained from the polyamide composition can be improved.

The measurement of Mw (B) / Mn (B) can be calculated using Mw (B) and Mn (B) obtained by using GPC as described in Examples described later.

((B) Crystallization enthalpy of amorphous semi-aromatic polyamide ΔH)
(B) The crystallization enthalpy ΔH of the amorphous semi-aromatic polyamide can be 15 J / g or less, and 10 J / g or less, from the viewpoint of mechanical properties, particularly water absorption rigidity and thermal rigidity. It can be 5 J / g or less, and can be 0 J / g.
(B) As a method for controlling the crystallization enthalpy ΔH of the amorphous semi-aromatic polyamide within the above range, for example, a method for increasing the ratio of the aromatic monomer to the dicarboxylic acid unit can be mentioned. From this point of view, the (B) amorphous semi-aromatic polyamide contains 75 mol of isophthalic acid as the (BA) dicarboxylic acid unit and (B) all the dicarboxylic acid units constituting the amorphous semi-aromatic polyamide. % Or more is preferable, and 100 mol% is more preferable.
(B) Examples of the device for measuring the crystallization enthalpy ΔH of the amorphous semi-aromatic polyamide include Diamond-DSC manufactured by PERKIN-ELMER.

((B) Tanδ peak temperature of amorphous semi-aromatic polyamide)
(B) The tan δ peak temperature of the amorphous semi-aromatic polyamide can be 90 ° C. or higher, 100 ° C. or higher and 160 ° C. or lower, 110 ° C. or higher and 150 ° C. or lower, 120. It can be ℃ or more and 145 ℃ or less, and can be 130 ℃ or more and 140 ℃ or less.
(B) As a method for controlling the tan δ peak temperature of the amorphous semi-aromatic polyamide within the above range, an increase in the ratio of the aromatic monomer to the dicarboxylic acid unit can be mentioned. From this point of view, the (B) amorphous semi-aromatic polyamide contains 75 mol of isophthalic acid as the (BA) dicarboxylic acid unit and (B) all the dicarboxylic acid units constituting the amorphous semi-aromatic polyamide. % Or more is preferable, and 100 mol% is more preferable.
(B) When the tan δ peak temperature of the amorphous semi-aromatic polyamide is at least the above lower limit value, it tends to be possible to obtain a polyamide composition having excellent water absorption rigidity and thermal rigidity. Further, when the tan δ peak temperature of the polyamide composition is not more than the above upper limit value, it tends to be possible to obtain a polyamide composition having an excellent surface appearance.
(B) The tan δ peak temperature of the amorphous semi-aromatic polyamide can be measured by using, for example, a viscoelasticity measuring and analyzing device (manufactured by Rheology: DVE-V4).

((B) Amino-terminal amount of amorphous semi-aromatic polyamide)
The amino-terminal amount of (B) amorphous semi-aromatic polyamide can be 5 μg or more and 100 μg or less, and 10 μg or more and 90 μg or less, with respect to 1 g of (B) amorphous semi-aromatic polyamide. , 20 μg or more and 80 μg or less, 30 μg or more and 70 μg or less, and 40 μg or more and 60 μg or less.
(B) When the amount of the amino terminal of the amorphous semi-aromatic polyamide is in the above range, it is possible to obtain an excellent polyamide composition due to discoloration due to heat or light.
The amount of amino terminal can be measured by neutralization titration.

((B) Amorphous semi-aromatic polyamide carboxy-terminal amount)
The amount of carboxy terminal of (B) amorphous semi-aromatic polyamide can be 50 μg or more and 300 μg or less, and 100 μg or more and 280 μg or less with respect to 1 g of (B) amorphous semi-aromatic polyamide. , 150 μg or more and 260 μg or less, 180 μg or more and 250 μg or less, and 200 μg or more and 240 μg or less.
(B) When the amount of the carboxy terminal of the amorphous semi-aromatic polyamide is in the above range, a polyamide composition having better fluidity and the like can be obtained. In addition, the surface appearance of the molded product obtained from the polyamide composition becomes more excellent.
The amount of carboxy terminal can be measured by neutralization titration.

[Total amount of amino-terminal amount and carboxy-terminal amount of polyamide]
The total amount of the amino-terminal amount and the carboxy-terminal amount of the polyamide ((A) crystalline polyamide and (B) amorphous semi-aromatic polyamide) is 150 μg or more and 350 μg or less, and 160 μg or more and 300 μg with respect to 1 g of polyamide. The following is preferable, 170 μg or more and 280 μg or less is more preferable, 180 μg or more and 270 μg or less is further preferable, and 190 μg or more and 260 μg or less is particularly preferable.
When the total amount of the amino-terminal amount and the carboxy-terminal amount of the polyamide ((A) crystalline polyamide and (B) amorphous semi-aromatic polyamide) is in the above range, a polyamide composition having better fluidity and the like can be obtained. can get. In addition, the surface appearance of the molded product obtained from the polyamide composition becomes more excellent.

[Mass ratio of (B) amorphous semi-aromatic polyamide to (A) total mass of crystalline polyamide and (B) amorphous semi-aromatic polyamide]
The content of (B) amorphous semi-aromatic polyamide with respect to 100 parts by mass of the total amount of (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide is preferably 10 parts by mass or more and 50 parts by mass or less. It is more preferably 15 parts by mass or more and 40 parts by mass or less, and further preferably 20 parts by mass or more and 30 parts by mass or less. When the mass ratio of (B) amorphous semi-aromatic polyamide to the total mass of (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide is in the above range, the strength and water absorption at 23 ° C. An excellent polyamide composition can be obtained by balancing with the strength at high temperature.

<(C) Carbon fiber>
The carbon fiber (C) contained in the polyamide composition of the present embodiment may have a perfect circular cross section or a flat cross section. Examples of such a flat cross section include, but are not limited to, a rectangle, an oval shape close to a rectangle, an ellipse shape, and a cocoon shape having a central portion in the longitudinal direction. Here, the "flattening ratio" in the present specification means a value represented by d2 / d1 when the major axis of the fiber cross section is d2 and the minor axis of the fiber cross section is d1. For example, a perfect circle has a flattening ratio of about 1.

Above all, from the viewpoint of imparting excellent mechanical strength to the polyamide composition, the number average fiber diameter is 3 μm or more and 30 μm or less, the weight average fiber length is 100 μm or more and 750 μm or less, and the weight average fiber length (l). A carbon fiber having an aspect ratio (l / d) of 10 or more and 100 or less with the number average fiber diameter (d) is preferably used.

Here, the "number average fiber diameter (d)" and the "weight average fiber length (l)" in the present specification can be obtained by the following methods. First, the polyamide composition is placed in an electric furnace to incinerate the contained organic matter. From the residue after the treatment, 100 or more carbon fibers are arbitrarily selected, observed with a scanning electron microscope (SEM), and the fiber diameters of these carbon fibers are measured to obtain the number average fiber diameter. Can be done. In addition, the weight average fiber length can be obtained by measuring the fiber length using SEM photographs of the above 100 or more carbon fibers taken at a magnification of 1000 times.

Further, the carbon fiber may further contain a sizing agent.
As the focusing agent, for example, a copolymer or an epoxy compound containing an unsaturated vinyl monomer containing a carboxylic acid anhydride and an unsaturated vinyl monomer excluding the unsaturated vinyl monomer containing a carboxylic acid anhydride as a constituent unit. , Polyurethane resins, homopolymers of acrylic acid, copolymers of acrylic acid with other copolymerizable monomers, and salts with these primary, secondary and tertiary amines. These sizing agents may be used alone or in combination of two or more.
Above all, from the viewpoint of the mechanical strength of the obtained polyamide composition, as the sizing agent, a single amount of unsaturated vinyl excluding the carboxylic acid anhydride-containing unsaturated vinyl monomer and the carboxylic acid anhydride-containing unsaturated vinyl monomer. One or more selected from the group consisting of a copolymer containing a body as a constituent unit, an epoxy compound, and a polyurethane resin is preferable. Further, it is selected from the group consisting of a copolymer and a polyurethane resin containing an unsaturated vinyl monomer containing a carboxylic acid anhydride and an unsaturated vinyl monomer excluding the unsaturated vinyl monomer containing a carboxylic acid anhydride as a constituent unit. More than one kind is more preferable.

The carbon fiber is continuously reacted by applying the above-mentioned sizing agent to the fiber and drying the fiber strand produced by using a known method such as a roller type applicator in the known manufacturing process of the fiber. It is obtained by letting.
The fiber strand may be used as it is as a roving, or may be further obtained in a cutting step and used as a chopped glass strand.

The sizing agent preferably imparts (adds) about 0.2% by mass or more and 3% by mass or less as a solid content to the total mass of carbon fibers, and preferably about 0.3% by mass or more and 2% by mass or less. It is more preferable to add (add). When the amount of the sizing agent added is equal to or more than the above lower limit as the solid content ratio with respect to the total mass of the carbon fibers, the sizing of the fibers can be maintained more effectively. On the other hand, when the amount of the sizing agent added is not more than the above upper limit value as the solid content ratio with respect to the total mass of the carbon fibers, the thermal stability of the obtained polyamide composition is further improved.
The strands may be dried after the cutting step or after the strands have been dried.

The number average fiber diameter of the carbon fibers is preferably 3 μm or more and 30 μm or less, more preferably 3 μm or more and 20 μm or less, further preferably 3 μm or more and 12 μm or less, and 3 μm or more and 9 μm or less, from the viewpoint of improving toughness and the surface appearance of the molded product. Is particularly preferable, and 4 μm or more and 6 μm or less are most preferable.
By setting the number average fiber diameter of the carbon fibers to the above upper limit value or less, a polyamide composition having better toughness and surface appearance of the molded product can be obtained. On the other hand, by setting the number average fiber diameter of the carbon fibers to the above lower limit value or more, an excellent polyamide composition can be obtained in terms of cost and balance between the handling surface of the powder and the physical properties (fluidity and the like). Further, by setting the number average fiber diameter of the carbon fibers to 3 μm or more and 9 μm or less, a polyamide composition having excellent vibration fatigue characteristics and slidability can be obtained.

[Inorganic fillers other than carbon fiber]
The polyamide composition of the present embodiment may further contain an inorganic filler other than the carbon fibers in addition to the carbon fibers (C).
As inorganic fillers other than carbon fiber, wollastonite, kaolin, mica, talc, calcium carbonate, magnesium carbonate, potassium titanate fiber, aluminum borate fiber from the viewpoint of improving the strength, rigidity and surface appearance of the molded product. Alternatively, clay is preferable. Wollastonite, kaolin, mica, talc, calcium carbonate or clay are more preferred. Wollastonite, kaolin, mica or talc are more preferred. Wollastonite, mica or talc are particularly preferred. These inorganic fillers may be used alone or in combination of two or more.

The average particle size of the inorganic filler other than the carbon fiber is preferably 0.01 μm or more and 38 μm or less, more preferably 0.03 μm or more and 30 μm or less, and 0.05 μm or more and 25 μm from the viewpoint of improving the toughness and the surface appearance of the molded product. The following is even more preferable, 0.10 μm or more and 20 μm or less is even more preferable, and 0.15 μm or more and 15 μm or less is particularly preferable.
By setting the average particle size of the inorganic filler other than the carbon fiber to the above upper limit value or less, a polyamide composition having better toughness and surface appearance of the molded product can be obtained. On the other hand, by setting the average particle size to the above lower limit value or more, an excellent polyamide composition can be obtained in terms of cost, handling surface of powder, and physical properties (fluidity, etc.).

Here, among the inorganic fillers, those having a needle-like shape such as wollastonite have a number average particle diameter (hereinafter, may be simply referred to as “average particle diameter”) as the average particle diameter. .. If the cross section is not a circle, the maximum value of the length is the (number average) fiber diameter.

Regarding the number average particle length of the needle-shaped inorganic filler described above (hereinafter, may be simply referred to as “average particle length”), the above-mentioned preferable range of the number average particle diameter and the following number average particle diameter (hereinafter, may be simply referred to as “average particle length”). A numerical range calculated from a preferable range of the aspect ratio (l / d) of the number average particle length (l) with respect to d) is preferable.

Although it has a needle-like shape, the aspect ratio (l / d) of the number average particle length (l) to the number average particle diameter (s) improves the surface appearance of the molded product and is used in injection molding machines and the like. From the viewpoint of preventing wear of the metallic parts, 1.5 or more and 10 or less are preferable, 2.0 or more and 5 or less are more preferable, and 2.5 or more and 4 or less are further preferable.

Further, the inorganic filler other than the carbon fiber may be surface-treated with a silane coupling agent, a titanate-based coupling agent, or the like.
Examples of the silane coupling agent include, but are not limited to, aminosilanes, mercaptosilanes, epoxysilanes, vinylsilanes and the like.
Examples of aminosilanes include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane and the like.
Examples of the mercaptosilanes include γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane.
These silane coupling agents may be used alone or in combination of two or more.
Among them, aminosilanes are preferable as the silane coupling agent.
Such a surface treatment agent may be treated in advance on the surface of the inorganic filler, or may be added when the polyamide and the inorganic filler are mixed. The amount of the surface treatment agent added is preferably 0.05% by mass or more and 1.5% by mass or less with respect to the total mass of the inorganic filler.

The total content of the inorganic filler is 5 parts by mass or more and 250 parts by mass or less with respect to 100 parts by mass of the total polyamide ((A) crystalline polyamide and (B) amorphous semi-aromatic polyamide) in the polyamide composition. Is preferable, 30 parts by mass or more and 250 parts by mass or less is more preferable, 50 parts by mass or more and 240 parts by mass or less is further preferable, 50 parts by mass or more and 200 parts by mass or less is particularly preferable, and 50 parts by mass or more and 150 parts by mass or less is most preferable. ..
By setting the total content of the inorganic filler to 100 parts by mass or more of the total polyamide in the polyamide composition, the effect of further improving the strength and rigidity of the obtained polyamide composition is exhibited. .. On the other hand, by setting the total content of the inorganic filler to 100 parts by mass or less of the above upper limit with respect to 100 parts by mass of the total polyamide in the polyamide composition, a polyamide composition having excellent extrudability and moldability can be obtained. ..

The content of the carbon fiber (C) is preferably 30% by mass or more and 65% by mass or less, more preferably 30% by mass or more and 60% by mass or less, and 35% by mass or more and 60% by mass, based on the total mass of the polyamide composition. More preferably, it is by mass or less.
By setting the content of the carbon fiber (C) to be equal to or higher than the above lower limit with respect to the total mass of the polyamide composition, the effect of further improving the strength and rigidity of the obtained polyamide composition is exhibited. On the other hand, by setting the content of the carbon fiber (C) to be equal to or lower than the above upper limit with respect to the total mass of the polyamide composition, a polyamide composition having excellent extrudability and moldability can be obtained.

Further, it is preferable that the contents of (B) amorphous semi-aromatic polyamide and (C) carbon fiber in the polyamide composition of the present embodiment satisfy the relationship of the following formula (1).

By satisfying the relationship of the above formula (1), the content mass of the (B) amorphous semi-aromatic polyamide and (C) carbon fiber in the polyamide composition of the present embodiment has good water absorption rigidity and thermal rigidity. A polyamide composition having an excellent surface appearance and pellet shape and a reduced amount of chips generated can be obtained.

<(D) Nucleating agent>
The polyamide composition of the present embodiment may further contain (D) a nucleating agent in addition to the above-mentioned components (A) to (C).

The nucleating agent means a substance that can obtain at least one of the following effects (1) to (3) by addition.
(1) The effect of raising the crystallization peak temperature of the polyamide composition.
(2) The effect of reducing the difference between the extrapolation start temperature and the extrapolation end temperature of the crystallization peak.
(3) The effect of making the spherulites of the obtained molded product finer or uniform in size.

Examples of the nucleating agent include, but are not limited to, talc, boron nitride, mica, kaolin, silicon nitride, carbon black, potassium titanate, molybdenum disulfide and the like. As the nucleating agent, only one type may be used alone, or two or more types may be used in combination.
Among them, talc or boron nitride is preferable as the nucleating agent from the viewpoint of the effect of the nucleating agent.

Further, since the effect of the nucleating agent is high, the number average particle size of the nucleating agent is preferably 0.01 μm or more and 10 μm or less.
The number average particle size of the nucleating agent can be measured by the following method. First, the molded product is dissolved in a solvent in which polyamide such as formic acid is soluble. Then, for example, 100 or more nucleating agents are arbitrarily selected from the obtained insoluble components. Then, it can be obtained by observing with an optical microscope, a scanning electron microscope, or the like and measuring the particle size.

The content of the nucleating agent in the polyamide composition of the present embodiment is 100 parts by mass with respect to 100 parts by mass of the total polyamide ((A) crystalline polyamide and (B) amorphous semi-aromatic polyamide) in the polyamide composition. It is preferably 0.001 part by mass or more and 1 part by mass or less, more preferably 0.001 part by mass or more and 0.5 part by mass or less, and further preferably 0.001 part by mass or more and 0.09 part by mass or less.
By setting the content of the nucleating agent to 100 parts by mass of the polyamide to be equal to or higher than the above lower limit, the heat resistance of the polyamide composition tends to be further improved, and the content of the nucleating agent is set to the polyamide. When the value is not more than the above upper limit with respect to 100 parts by mass, a polyamide composition having better toughness can be obtained.

<(E) Lubricant>
The polyamide composition of the present embodiment may further contain (E) a lubricant in addition to each of the above components (A) to (C).

The lubricating material contained in the polyamide composition of the present embodiment is not particularly limited, and examples thereof include higher fatty acids, higher fatty acid metal salts, higher fatty acid esters, higher fatty acid amides, and the like.

[Higher fatty acids]
Examples of the higher fatty acid include linear or branched chain-like saturated or unsaturated aliphatic monocarboxylic acids having 8 or more and 40 or less carbon atoms.
Examples of the saturated or unsaturated aliphatic monocarboxylic acid having 8 or more carbon atoms and 40 or less carbon atoms include lauric acid, palmitic acid, stearic acid, behenic acid, and montanic acid.
Examples of the branched chain saturated aliphatic monocarboxylic acid having 8 or more carbon atoms and 40 or less carbon atoms include isopalmitic acid and isostearic acid.
Examples of the linear unsaturated aliphatic monocarboxylic acid having 8 or more carbon atoms and 40 or less carbon atoms include oleic acid and erucic acid.
Examples of the branched chain unsaturated aliphatic monocarboxylic acid having 8 or more carbon atoms and 40 or less carbon atoms include isooleic acid and the like.
One type of each of these higher fatty acids may be used alone, or two or more types may be used in combination.
Among them, stearic acid or montanic acid is preferable as the higher fatty acid.

[Higher fatty acid metal salt]
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 and Group 3 elements, zinc, aluminum and the like in the Periodic Table of the Elements.
Examples of Group 1 elements in the Periodic Table of the Elemental Period include sodium, potassium and the like.
Examples of Group 2 elements in the Periodic Table of the Elements include calcium and magnesium.
Examples of Group 3 elements in the Periodic Table of the Elements include scandium and yttrium.
Among them, as the metal element, the first and second group elements of the Periodic Table of the Elemental Period or aluminum is preferable, and sodium, potassium, calcium, magnesium, or aluminum is more preferable.

Specific examples of the higher fatty acid metal salt include calcium stearate, aluminum stearate, zinc stearate, magnesium stearate, calcium montanate, sodium montanate, calcium palmitate and the like.
Each of these higher fatty acid metal salts may be used alone or in combination of two or more.
Among them, as the higher fatty acid metal salt, a metal salt of montanic acid or a metal salt of stearic acid is preferable.

[Higher fatty acid ester]
The higher fatty acid ester is an esterified product of a higher fatty acid and an alcohol.
As the higher fatty acid ester, an ester of an aliphatic carboxylic acid having 8 or more and 40 or less carbon atoms and an aliphatic alcohol having 8 or more and 40 or less carbon atoms is preferable.
Examples of the aliphatic alcohol having 8 or more carbon atoms and 40 or less carbon atoms include stearyl alcohol, behenyl alcohol, and lauryl alcohol.
Specific examples of the higher fatty acid ester include stearyl stearate and behenic behenate.
Each of these higher fatty acid esters may be used alone or in combination of two or more.

[Higher fatty acid amide]
The higher fatty acid amide is an amide compound of a higher fatty acid.
Examples of the higher fatty acid amide include stearate amide, oleic acid amide, erucate amide, ethylene bisstearyl amide, ethylene bisoleyl amide, N-stearyl steayl amide, N-stearyl erucate amide and the like.
Each of these higher fatty acid amides may be used alone or in combination of two or more.

The content of the lubricant in the polyamide composition of the present embodiment is 0.001 with respect to 100 parts by mass of the polyamide ((A) crystalline polyamide and (B) amorphous aromatic polyamide) in the polyamide composition. It is preferably by mass or more and 1 part by mass or less, and more preferably 0.03 part by mass or more and 0.5 part by mass or less.
When the content of the lubricant is within the above range, a polyamide composition having excellent releasability and plasticization time stability and having excellent toughness can be obtained. In addition, it is possible to more effectively prevent an extreme decrease in the molecular weight of the polyamide due to the cleavage of the molecular chain.

<(F) Heat stabilizer>
The polyamide composition of the present embodiment may further contain (F) a heat stabilizer in addition to the above-mentioned components (A) to (C).

The heat stabilizer is not limited to the following, but is not limited to, for example, a phenol-based heat stabilizer, a phosphorus-based heat stabilizer, an amine-based heat stabilizer, Group 3 and Group 4 and Groups 11 to 14 of the Periodic Table of the Elements. Examples include metal salts of the elements of the above, halides of alkali metals and alkaline earth metals.

[Phenolic heat stabilizer]
Examples of the phenolic heat stabilizer include, but are not limited to, hindered phenol compounds. The hindered phenol compound has a property of imparting excellent heat resistance and light resistance to resins and fibers such as polyamide.

The hindered phenol compound is not limited to the following, and is, for example, N, N'-hexane-1,6-diylbis [3- (3,5-di-t-butyl-4-hydroxyphenylpropi). Onamide), pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], N, N'-hexamethylenebis (3,5-di-t-butyl-) 4-Hydroxy-hydrocinnamamide), triethyleneglycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 3,9-bis {2- [3- (3) -T-butyl-4-hydroxy-5-methylphenyl) propynyloxy] -1,1-dimethylethyl} -2,4,8,10-tetraoxaspiro [5,5] undecane, 3,5-di-t -Butyl-4-hydroxybenzylphosphonate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 1,3,5 -Tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanuric acid and the like can be mentioned.
These hindered phenol compounds may be used alone or in combination of two or more.
In particular, from the viewpoint of improving heat-resistant aging properties, the hindered phenol compound includes N, N'-hexane-1,6-diylbis [3- (3,5-di-t-butyl-4-hydroxyphenylpropionamide). )] Is preferable.

When a phenol-based heat stabilizer is used, the content of the phenol-based heat stabilizer in the polyamide composition is preferably 0.01% by mass or more and 1% by mass or less, preferably 0.1% by mass, based on the total mass of the polyamide composition. More preferably, it is by mass% or more and 1% by mass or less.
When the content of the phenolic heat stabilizer is within the above range, the heat-resistant aging property of the polyamide composition can be further improved, and the amount of gas generated can be further reduced.

[Phosphorus heat stabilizer]
The phosphorus-based heat stabilizer is not limited to, but is not limited to, for example, pentaerythritol type phosphite compound, trioctylphosphite, trilaurylphosphite, tridecylphosphite, octyldiphenylphosphite, trisisodecyl. Phenyl diisodecyl phosphite, phenyldi (tridecyl) phosphite, diphenylisooctylphosphite, diphenylisodecylphosphite, diphenyl (tridecyl) phosphite, triphenylphosphite, tris (nonylphenyl) phosphite, tris (2) , 4-di-t-butylphenyl) phosphite, tris (2,4-di-t-butyl-5-methylphenyl) phosphite, tris (butoxyethyl) phosphite, 4,4'-butylidene-bis ( 3-Methyl-6-t-butylphenyl-tetra-tridecyl) diphosphite, tetra (C12-C15 mixed alkyl) -4,4'-isopropylidene diphenyldiphosphite, 4,4'-isopropylidenebis (2-t) -Butylphenyl) -di (nonylphenyl) phosphite, tris (biphenyl) phosphite, tetra (tridecyl) -1,1,3-tris (2-methyl-5-t-butyl-4-hydroxyphenyl) butanji Phosphite, Tetra (Tridecyl) -4,4'-Butylidenebis (3-Methyl-6-t-Butylphenyl) Diphosphite, Tetra (C1-C15 mixed alkyl) -4,4'-Isopropyridene diphenyldiphosphite, Tris (Mono, di-mixed nonylphenyl) phosphite, 4,4'-isopropylidenebis (2-t-butylphenyl) -di (nonylphenyl) phosphite, 9,10-di-hydro-9-oxa-9- Oxa-10-phosphaphenanthrene-10-oxide, tris (3,5-di-t-butyl-4-hydroxyphenyl) phosphite, hydride-4,4'-isopropyridene diphenylpolyphosphite, bis (Octylphenyl) -bis (4,4'-butylidenebis (3-methyl-6-t-butylphenyl))-1,6-hexanoldiphosphite, hexatridecyl-1,1,3-tris (2-) Methyl-4-hydroxy-5-t-butylphenyl) diphosphite, tris (4,4'-isopropylidenebis (2-t-butylphenyl)) phosphite, tris (1,3-stearoyloxyisopropyl) ) Phosphite, 2,2-methylenebis (4,6-di-t-butylphenyl) octylphosphite, 2,2-methylenebis (3-methyl-4,6-di-t-butylphenyl) 2-ethylhexylphos Fight, Tetrakiss (2,4-di-t-butyl-5-methylphenyl) -4,4'-biphenylenediphosphite, Tetrakiss (2,4-di-t-butylphenyl) -4,4'-bipheni Examples include range phosphite.
These phosphorus-based heat stabilizers may be used alone or in combination of two or more.
Among them, as phosphorus-based heat stabilizers, pentaerythritol-type phosphite compounds and tris (2,4-di-t-butylphenyl) are used from the viewpoint of further improving the heat-resistant aging property of the polyamide composition and reducing the amount of gas generated. ) One or more selected from the group consisting of phosphite is preferable.

The pentaerythritol-type phosphite compound is not limited to the following, and is, for example, 2,6-di-t-butyl-4-methylphenyl-phenyl-pentaerythritol diphosphite, 2,6-di-. t-butyl-4-methylphenyl-methyl-pentaerythritol diphosphite, 2,6-di-t-butyl-4-methylphenyl-2-ethylhexyl-pentaerythritol diphosphite, 2,6-di-t- Butyl-4-methylphenyl-isodecyl-pentaerythritol diphosphite, 2,6-di-t-butyl-4-methylphenyl-lauryl-pentaerythritol diphosphite, 2,6-di-t-butyl-4- Methylphenyl-isotridecyl-pentaerythritol diphosphite, 2,6-di-t-butyl-4-methylphenyl-stearyl pentaerythritol diphosphite, 2,6-di-t-butyl-4-methylphenyl cyclohexyl -Pentaerythritol diphosphite, 2,6-di-t-butyl-4-methylphenyl-benzyl-pentaerythritol diphosphite, 2,6-di-t-butyl-4-methylphenyl ethylcellosolve-pentaerythritol Diphosphite, 2,6-di-t-butyl-4-methylphenyl-butylcarbitol-pentaerythritol diphosphite, 2,6-di-t-butyl-4-methylphenyl-octylphenyl-pentaerythritol di Phosphite, 2,6-di-t-butyl-4-methylphenyl-nonylphenyl pentaerythritol diphosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite, Bis (2,6-di-t-butyl-4-ethylphenyl) pentaerythritol diphosphite, 2,6-di-t-butyl-4-methylphenyl-2,6-di-t-butylphenyl-penta Ellisritol diphosphite, 2,6-di-t-butyl-4-methylphenyl-2,4-di-t-butylphenyl-pentaerythritol diphosphite, 2,6-di-t-butyl-4-methyl Phenyl-2,4-di-t-octylphenyl-pentaerythritol diphosphite, 2,6-di-t-butyl-4-methylphenyl-2-cyclohexylphenyl-pentaerythritol diphosphite, 2,6-di -T-Amil-4-methylphenyl-phenyl pentaeris Tritoll diphosphite, bis (2,6-di-t-amyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,6-di-t-octyl-4-methylphenyl) pentaerythritol diphos Fight etc. can be mentioned.
These pentaerythritol-type phosphite compounds may be used alone or in combination of two or more.

Among them, as the pentaerythritol type phosphite compound, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite and bis (2) are used from the viewpoint of reducing the amount of gas generated in the polyamide composition. , 6-di-t-butyl-4-ethylphenyl) pentaerythritol diphosphite, bis (2,6-di-t-amyl-4-methylphenyl) pentaerythritol diphosphite, and bis (2,6) One or more selected from the group consisting of -di-t-octyl-4-methylphenyl) pentaerythritol diphosphite is preferable, and bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphos is preferable. Fight is more preferred.

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, preferably 0.1% by mass, based on the total mass of the polyamide composition. More preferably, it is by mass% or more and 1% by mass or less.
When the content of the phosphorus-based heat stabilizer is within the above range, the heat-resistant aging property of the polyamide composition can be further improved, and the amount of gas generated can be further reduced.

[Amine-based heat stabilizer]
The amine-based heat stabilizer is not limited to the following, and is, for example, 4-acetoxy-2,2,6,6-tetramethylpiperidine, 4-stearoyloxy-2,2,6,6-tetra. Methylpiperidine, 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, 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-tetra Methyl-4-piperidyl) -malonate, bis (2,2,6,6-tetramethyl-4-piperidyl) -sevacate, 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, bis (2,2,6,6-tetramethyl-4-piperidyltrilen-2,4-dicarbamate, bis (2,2,6,6-tetramethyl-4-piperidyloxy) 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) -T-butyl-4-hydroxyphenyl) propionyloxy} butyl] -4- [3- (3,5-di-t-butyl-4-hydroxyphenyl) Enyl) propionyloxy] 2,2,6,6-tetramethylpiperidin, 1,2,3,4-butanetetracarboxylic acid and 1,2,2,6,6-pentamethyl-4-piperidinol and β, β, Examples thereof include β', β'-tetramethyl-3,9- [2,4,8,10-tetraoxaspiro (5,5) undecane] condensate with diethanol.
These amine-based heat stabilizers may be used alone or in combination of two or more.

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, preferably 0.1% by mass, based on the total mass of the polyamide composition. More preferably, it is by mass% or more and 1% by mass or less.
When the content of the amine-based heat stabilizer is within the above range, the heat-resistant aging property of the polyamide composition can be further improved, and the amount of gas generated can be further reduced.

[Metal salts of Group 3 and Group 4 and Group 11-14 elements of the Periodic Table of the Elements]
The metal salts of the elements of the 3rd group, the 4th group and the 11th to 14th groups of the Periodic Table of the Elemental Periodic Table are not limited as long as they are the salts of the metals belonging to these groups.
Above all, a copper salt is preferable from the viewpoint of further improving the heat-resistant aging property of the polyamide composition. The copper salt is not limited to the following, and is, for example, copper halide, copper acetate, copper propionate, copper benzoate, copper adipate, copper terephthalate, copper isophthalate, copper salicylate, copper nicotinate, stearic acid. Examples thereof include copper and a copper complex salt in which copper is coordinated with a chelating agent.
Examples of the copper halide include copper iodide, cuprous bromide, cupric bromide, and cuprous chloride.
Examples of the chelating agent include ethylenediamine and ethylenediaminetetraacetic acid.
These copper salts may be used alone or in combination of two or more.
Among them, as the copper salt, one or more selected from the group consisting of copper iodide, cupric bromide, cupric bromide, cupric chloride and copper acetate is preferable, and the copper salt is made of copper iodide and copper acetate. One or more selected from the group is more preferable. When the above-mentioned preferable copper salts are used, they are superior in heat-resistant aging property and more effectively suppress metal corrosion of screws and cylinders during extrusion (hereinafter, may be simply referred to as "metal corrosion"). A possible polyamide composition is obtained.

When a copper salt is used as the heat stabilizer, the content of the copper salt in the polyamide composition is 0 with respect to the total mass of the polyamide ((A) crystalline polyamide and (B) amorphous semi-aromatic polyamide). It is preferably 0.01% by mass or more and 0.60% by mass or less, and more preferably 0.02% by mass or more and 0.40% by mass or less.

When the content of the copper salt is within the above range, the heat-resistant aging property of the polyamide composition can be further improved, and copper precipitation and metal corrosion can be more effectively suppressed.

Further, the content concentration of the copper element derived from the copper salt is the polyamide ((A) crystalline polyamide and (B) amorphous semi-aromatic polyamide) 10 from the viewpoint of improving the heat-resistant aging property of the polyamide composition. With respect to ⁶ parts by mass (1 million parts by mass), 10 parts by mass or more and 2000 parts by mass or less are preferable, 30 parts by mass or more and 1500 parts by mass or less are more preferable, and 50 parts by mass or more and 500 parts by mass or less are further preferable.

[Halogens of alkali metals and alkaline earth metals]
Examples of the halides of the alkali metal and the alkaline earth metal include, but are not limited to, potassium iodide, potassium bromide, potassium chloride, sodium iodide, sodium chloride and the like.
As the halides of these alkali metals and alkaline earth metals, one type may be used alone, or two or more types may be used in combination.
Among them, as the halide of the alkali metal and the alkaline earth metal, one or more selected from the group consisting of potassium iodide and potassium bromide is preferable from the viewpoint of improving heat aging property and suppressing metal corrosion, and iodide is preferable. Potassium is more preferred.

When alkali metal and alkaline earth metal halides are used, the content of the alkali metal and alkaline earth metal halides in the polyamide composition is determined by the polyamide ((A) crystalline polyamide and (B) amorphous semi-crystalline). Aromatic polyamide) With respect to 100 parts by mass, 0.05 parts by mass or more and 20 parts by mass or less are preferable, and 0.2 parts by mass or more and 10 parts by mass or less are more preferable.
When the content of the halide of the alkali metal and the alkaline earth metal is within the above range, the heat-resistant aging property of the polyamide composition can be further improved, and copper precipitation and metal corrosion can be suppressed more effectively. can.

As the component of the heat stabilizer described above, only one kind may be used alone, or two or more kinds may be used in combination.
Among them, as the heat stabilizer, a mixture of a copper salt and a halide of an alkali metal and an alkaline earth metal is preferable from the viewpoint of further improving the heat aging property of the polyamide composition.

The content ratio of the copper salt to the halides of the alkali metal and the alkaline earth metal is preferably 2/1 or more and 40/1 or less as the molar ratio of halogen to copper (halogen / copper), 5/1 or more and 30 /. 1 or less is more preferable.
When the molar ratio of halogen to copper (halogen / copper) is within the above range, the heat aging property of the polyamide composition can be further improved.
Further, when the molar ratio of halogen to copper (halogen / copper) is at least the above lower limit value, precipitation of copper and metal corrosion can be suppressed more effectively. On the other hand, when the molar ratio of halogen to copper (halogen / copper) is not more than the above upper limit value, corrosion of screws and the like of the molding machine can be more effectively prevented without impairing mechanical properties (toughness and the like).

<(G) Other resin>
The polyamide composition of the present embodiment may further contain (G) and other resins in addition to the above-mentioned components (A) to (C).

Other resins contained in the polyamide composition of the present embodiment are not limited to the following, and examples thereof include polyester, liquid crystal polyester, polyphenylene sulfide, polycarbonate, polyarylate, phenol resin, and epoxy resin.

[polyester]
Examples of the polyester include, but are not limited to, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene terephthalate, polyethylene naphthalate and the like.

The content of the other resin in the polyamide composition of the present embodiment is preferably 1 part by mass or more and 200 parts by mass or less, preferably 5 parts by mass or more and 100 parts by mass with respect to 100 parts by mass of the total resin components in the polyamide composition. It is more preferably 5 parts by mass or more and 50 parts by mass or less.
When the content of the other resin in the polyamide composition of the present embodiment is within the above range, the polyamide composition having better heat resistance and releasability can be obtained.

<At least one selected from the group consisting of (H) phosphite metal salt and hypophosphorous acid metal salt>
In the polyamide composition of the present embodiment, in addition to the above components (A) to (C), at least one selected from the group consisting of (H) phosphite metal salt and hypophosphorous acid metal salt is further added. It may be contained.

Examples of the phosphorous acid metal salt and the hypophosphorous acid metal salt contained in the polyamide composition of the present embodiment include phosphorous acid, hypophosphorous acid, pyrophosphorous acid or diphosphorous acid, and a periodic table. Examples thereof include salts with Group 1 and Group 2 elements, manganese, zinc, aluminum, ammonia, alkylamines, cycloalkylamines or diamines.
Among them, as the phosphorous acid metal salt and the hypophosphite metal salt, sodium hypophosphite, calcium hypophosphite, or magnesium hypophosphite is preferable.
By containing at least one selected from the group consisting of these phosphite metal salts and hypophosphorous acid metal salts, a polyamide composition having excellent extrusion processability and molding process stability can be obtained.

<(I) Phosphite ester compound>
The polyamide composition of the present embodiment may further contain (I) a phosphite ester compound in addition to each of the above components (A) to (C).

Examples of the phosphite ester compound contained in the polyamide composition of the present embodiment include triphenyl phosphite and tributyl phosphite.
By adding the phosphite ester compound, a polyamide composition having better extrusion processability and molding process stability can be obtained.

Specific examples of the phosphite compound include trioctylphosphite, trilaurylphosphite, tridecylphosphite, octyl-diphenylphosphite, trisisodecylphosphite, phenyldiisodecylphosphite, and phenyldi (tridecyl) phos. Fight, diphenylisooctylphosphite, diphenylisodecylphosphite, diphenyltridecylphosphite, triphenylphosphite, tris (nonylphenyl) phosphite, tris (2,4-di-t-butylphenyl) phosphite, bis [2,4-bis (1,1-dimethylethyl) -6-methylphenyl] ethyl phosphite, bis (2,4-di-t-butylphenyl) pentaerythritol-di-phosphite, bis (2,6) -Di-t-butyl-4-methylphenyl) pentaerythritol-di-phosphite, 2,2-methylenebis (4,6-di-t-butylphenyl) octylphosphite, 4,4'-butylidene-bis (4,6-di-t-butylphenyl) 3-Methyl-6-t-butylphenyl-di-tridecyl) phosphite, 1,1,3-tris (2-methyl-4-ditridecylphosphite-5-t-butyl-phenyl) butane, 4,4 '-Isopropylidenebis (phenyl-dialkylphosphite), Tris (2,4-di-t-butylphenyl) phosphite, 2,2-methylenebis (4,6-di-t-butylphenyl) octylphosphite, Examples thereof include bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-di-phosphite.
These phosphite ester compounds may be used alone or in combination of two or more.

<(J) Other additives>
In addition to the components (A) to (C) above, the polyamide composition of the present embodiment is conventionally used for polyamide (J) and others as long as the effects of the polyamide composition of the present embodiment are not impaired. Additives can also be included. (J) Other additives include, for example, colorants such as pigments and dyes (including colored master batches), flame retardants, fibrillating agents, fluorescent bleaching agents, plasticizers, antioxidants, ultraviolet absorbers, and charging. Examples thereof include an inhibitor, a fluidity improver, a spreading agent, and an elastomer.

The content of (J) and other additives in the polyamide composition of the present embodiment varies depending on the type, use of the polyamide composition, etc., as long as the effect of the polyamide composition of the present embodiment is not impaired. There are no particular restrictions.

<Manufacturing method of polyamide composition>
As a method for producing the polyamide composition of the present embodiment, the above-mentioned (A) crystalline polyamide, the above-mentioned (B) amorphous semi-aromatic polyamide, the above-mentioned (C) carbon fiber, and the raw material components contained therein are melt-kneaded. The manufacturing method includes the process, and the method is not particularly limited.
For example, the setting of the extruder includes a step of melting and kneading the raw material components containing the (A) crystalline polyamide, the (B) amorphous semi-aromatic polyamide, and the (C) carbon fiber contained in the extruder. A method in which the temperature is preferably Tm2 + 30 ° C. or lower, which is the melting peak temperature of the polyamide composition described later, is preferable.

Examples of the method of melt-kneading the raw material component containing the polyamide include the following methods (1) and (2).
(1) A method in which polyamide and other raw materials are mixed using a tumbler, a Henschel mixer, etc., and supplied to a melt kneader for kneading.
(2) A method of blending other raw materials from a side feeder into a polyamide melted by a single-screw or twin-screw extruder.

In the method of supplying the components constituting the polyamide composition to the melt kneader, all the components may be supplied to the same supply port at once, or the components may be supplied from different supply ports.

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 apparatus for performing melt-kneading is not particularly limited, and known apparatus such as a single-screw or twin-screw extruder, a Banbury mixer, a melt-kneader (mixing roll, etc.) and the like can be used.

The blending amount of each component in producing the polyamide composition of the present embodiment is the same as the content of each component in the above-mentioned polyamide composition.

<Physical characteristics of polyamide composition>
Specifically, the tan δ peak temperature of the polyamide composition of this embodiment can be measured by the method described in Examples described later.
The molecular weight, melting point Tm2, crystallization enthalpy ΔH, crystallization peak temperature Tc, amino terminal amount / (amino terminal amount + carboxy terminal amount), and gloss value of the obtained molded product of the polyamide composition of the present embodiment are as follows. It can be measured by the method shown in.

[Weight average molecular weight (Mw) of polyamide composition]
A weight average molecular weight (Mw) can be used as an index of the molecular weight of the polyamide composition.
The weight average molecular weight (Mw) of the polyamide composition is preferably 15,000 or more and 35,000 or less, more preferably 17,000 or more and 35,000 or less, further preferably 20,000 or more and 35,000 or less, particularly preferably 22,000 or more and 34,000 or less, and most preferably 24,000 or more and 33,000 or less. ..
When the weight average molecular weight (Mw) of the polyamide composition is in the above range, a polyamide excellent in mechanical properties, particularly water absorption rigidity, thermal rigidity, fluidity and the like can be obtained. Further, the molded product obtained from the polyamide composition has a better surface appearance.
Examples of the method for controlling the Mw of the polyamide composition within the above range include the use of (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide having a weight average molecular weight within the above range. Be done.
The Mw of the polyamide composition can be measured using GPC.

[Total content of total polyamide in the polyamide composition having a number average molecular weight Mn of 500 or more and 2000 or less]
Among the total polyamides in the polyamide composition, the total content of those having a number average molecular weight Mn of 500 or more and 2000 or less is 0.5% by mass or more and 2.5% by mass with respect to the total mass of the polyamides in the polyamide composition. %, 0.8% by mass or more and less than 2.5% by mass, 1.0% by mass or more and less than 2.5% by mass, 1.2% by mass or more. It can be less than 2.5% by mass, and can be 1.4% by mass or more and less than 2.5% by mass.
Among the total polyamides in the polyamide composition, those having a number average molecular weight Mn of 500 or more and 2000 or less and having a content of not more than the above lower limit value are more excellent in fluidity, and the molded product obtained from the polyamide composition is The surface appearance is better. Further, when it is less than the above upper limit value, gas generation during molding can be suppressed more effectively.

As a method for controlling the total content of the total polyamide in the polyamide composition having a number average molecular weight Mn of 500 or more and 2000 or less within the above range, for example, (B) the molecular weight of the amorphous semi-aromatic polyamide is used. There is a method of adjusting. At this time, the weight average molecular weight (Mw (B)) of the (B) amorphous semi-aromatic polyamide is preferably 10,000 or more and 25,000 or less.
The total content of the total polyamide in the polyamide composition having a number average molecular weight Mn of 500 or more and 2000 or less can be determined from the elution curve obtained by using GPC.
Further, in the GPC measurement, the composition containing (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide contains other components that are soluble in the solvent that dissolves the polyamide. In this case, GPC measurement can be performed after extracting and removing the other components using a solvent in which the polyamide is insoluble but the other components are soluble. Further, the inorganic filler such as (C) carbon fiber, which is insoluble in the solvent for dissolving the polyamide, is dissolved in the solvent for dissolving the polyamide composition, and then filtered to remove the insoluble matter, and then GPC measurement is performed. It can be carried out.

[Difference between (A) weight average molecular weight Mw (A) of crystalline polyamide and (B) weight average molecular weight Mw (B) of (B) amorphous semi-aromatic polyamide {Mw (A) -Mw (B)}]
The difference between (A) the weight average molecular weight Mw (A) of the crystalline polyamide and the weight average molecular weight Mw (B) of the (B) amorphous semi-aromatic polyamide {Mw (A) -Mw (B)} is 2000 or more. It can be 5000 or more, it can be 8000 or more, it can be 10,000 or more, and it can be 12000 or more. When {Mw (A) -Mw (B)} is at least the above lower limit value, (B) amorphous semi-aromatic polyamide forms a micro-sized domain, and the polyamide composition is superior in water absorption rigidity and thermal rigidity. It can be a thing.

[Molecular weight distribution of polyamide composition]
The molecular weight distribution of the polyamide composition of the present embodiment uses the weight average molecular weight (Mw) / number average molecular weight (Mn) as an index.
The lower limit of the weight average molecular weight (Mw) / number average molecular weight (Mn) of the polyamide composition of the present embodiment can be 1.0, 1.7, or 1.8. Can be set to 1.9.
On the other hand, the upper limit of Mw / Mn of the polyamide composition of the present embodiment can be 2.4, 2.3, or 2.2.
That is, the Mw / Mn of the polyamide composition of the present embodiment can be 2.4 or less, 1.0 or more and 2.4 or less, and 1.7 or more and 2.3 or less. It can be 1.8 or more and 2.3 or less, and can be 1.9 or more and 2.1 or less.
When Mw / Mn is in the above range, a polyamide composition having better fluidity and the like tends to be obtained. Further, the molded product obtained from the polyamide composition tends to have a better surface appearance.

Examples of the method for controlling Mw / Mn of the polyamide composition within the above range include (B) a method of setting Mw (B) / Mn (B) of the amorphous semi-aromatic polyamide within the above range.
When an aromatic compound unit is contained in the molecular structure of the polyamide composition, the molecular weight distribution (Mw / Mn) tends to increase as the molecular weight increases. When the molecular weight distribution is within the above range, the proportion of polyamide molecules having a three-dimensional structure of the molecule can be further lowered, and the three-dimensional structure of the molecule can be more preferably prevented during high-temperature processing, and the fluidity can be improved. Can be kept better. This tends to improve the surface appearance of the molded product obtained from the polyamide composition.
The Mw / Mn of the polyamide composition can be calculated using the weight average molecular weight (Mw) and the number average molecular weight (Mn) obtained by using GPC.

[Melting point Tm2 of polyamide composition]
The melting point Tm2 of the polyamide composition can be 200 ° C. or higher, 220 ° C. or higher and 270 ° C. or lower, 230 ° C. or higher and 265 ° C. or lower, and 240 ° C. or higher and 260 ° C. or lower. The temperature can be 250 ° C or higher and 260 ° C or lower.
When the melting point Tm2 of the polyamide composition is at least the above lower limit value, it tends to be possible to obtain a polyamide composition having superior thermal rigidity and the like.
On the other hand, when the melting point Tm2 of the polyamide composition is not more than the above upper limit value, there is a tendency that thermal decomposition of the polyamide composition in melt processing such as extrusion and molding can be further suppressed.

[Crystallization Enthalpy ΔH of Polyamide Composition]
The lower limit of the crystallization enthalpy ΔH of the polyamide composition can be 10 J / g, 14 J / g, and 18 J / g from the viewpoint of mechanical properties, particularly water absorption rigidity and thermal rigidity. It can be 20 J / g. On the other hand, the upper limit of the crystallization enthalpy ΔH is not particularly limited, and the higher the value, the more preferable.
Examples of the method for controlling the crystallization enthalpy ΔH of the polyamide composition within the above range include a method for controlling the contents of (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide within the above range. Can be mentioned.
Examples of the device for measuring the melting point Tm2 and the crystallization enthalpy ΔH of the polyamide composition include Diamond-DSC manufactured by PERKIN-ELMER.

[Tanδ peak temperature of polyamide composition]
The lower limit of the tan δ peak temperature of the polyamide composition is preferably 90 ° C, more preferably 100 ° C, further preferably 110 ° C, and particularly preferably 120 ° C.
The upper limit of the tan δ peak temperature of the polyamide composition is preferably 150 ° C, more preferably 140 ° C, and even more preferably 130 ° C.
That is, the tan δ peak temperature of the polyamide composition is preferably 90 ° C. or higher and 150 ° C. or lower, more preferably 100 ° C. or higher and 140 ° C. or lower, further preferably 110 ° C. or higher and 130 ° C. or lower, and particularly preferably 120 ° C. or higher and 130 ° C. or lower.
When the tan δ peak temperature of the polyamide composition is at least the above lower limit value, it tends to be possible to obtain a polyamide composition having higher water absorption rigidity and thermal rigidity. Further, when the tan δ peak temperature of the polyamide composition is not more than the above upper limit value, the molded product obtained from the polyamide composition has a better surface appearance.
As a method of controlling the tan δ peak temperature of the polyamide composition within the above range, for example, a method of controlling the blending ratio of (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide within the above range is used. Can be mentioned.

[Crystallization peak temperature Tc obtained when the polyamide composition is cooled at 20 ° C./min]
The crystallization peak temperature Tc (° C.) obtained when the polyamide composition is cooled at 20 ° C./min can be 160 ° C. or higher and 240 ° C. or lower, 170 ° C. or higher and 230 ° C. or lower, 180 ° C. or higher. The temperature can be ℃ or higher and 225 ° C or lower, 190 ° C or higher and 220 ° C or lower, and 200 ° C or higher and 215 ° C or lower.
When the crystallization peak temperature Tc (° C.) of the polyamide composition is at least the above lower limit value, a polyamide composition having better releasability during molding can be obtained.
On the other hand, when the crystallization peak temperature Tc (° C.) of the polyamide composition is not more than the above upper limit value, the surface appearance of the molded product obtained from the polyamide composition becomes more excellent.

The melting point crystallization peak temperature Tc of the polyamide composition of the present embodiment can be measured according to JIS-K7121.
Examples of the device for measuring the crystallization peak temperature Tc include Diamond-DSC manufactured by PERKIN-ELMER.
Examples of the method for controlling the crystallization peak temperature Tc of the polyamide within the above range include a method for controlling the blending ratio of (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide within the above range. Be done.

[Ratio of amino-terminal mass to total mass of amino-terminal amount and carboxy-terminal amount in polyamide composition {amino-terminal amount / (amino-terminal amount + carboxy-terminal amount)}]
The ratio of the amount of amino-terminal to the total mass of the amount of amino-terminal and the amount of carboxy-terminal in the polyamide composition {amino-terminal amount / (amino-terminal amount + carboxy-terminal amount)} shall be 0.25 or more and less than 0.4. It can be 0.35 or more and less than 0.4, and 0.25 or more and less than 0.35. When the ratio of the mass of the amino terminal to the total mass of the amount of the amino terminal and the amount of the carboxy terminal is at least the above lower limit value, corrosion of the extruder or the molding machine can be suppressed more effectively. When the ratio of the mass of the amino terminal to the total mass of the amount of the amino terminal and the amount of the carboxy terminal is less than the above upper limit value, a polyamide composition excellent in discoloration with respect to heat or light can be obtained.
The amount of amino terminal and the amount of carboxy terminal can be measured by neutralization titration, and the ratio of the mass of amino terminal to the total mass of the amount of amino terminal and the amount of carboxy terminal based on the measured amount of amino terminal and carboxy terminal {amino terminal. Amount / (amino terminal amount + carboxy terminal amount)} can be calculated.

[Gloss value of molded product obtained from polyamide composition]
The surface gloss value of the molded product obtained from the polyamide composition can be 50 or more, 55 or more, and 60 or more. When the surface gloss value of the polyamide composition is at least the above lower limit value, it is more suitable as a molding material for various parts such as automobiles, electric and electronic, industrial materials, industrial materials, daily use and household products. Can be used.
The surface gloss value can be measured by the method shown in Examples described later.

≪Molded product≫
The molded product of this embodiment is formed by molding the polyamide composition of the above embodiment.
The molded product of this embodiment is excellent in mechanical properties, particularly water absorption rigidity, thermal rigidity, and surface appearance.

The molded product of this embodiment can be obtained by molding the above-mentioned polyamide composition using a known molding method.
Known molding methods are not limited to the following, but are, for example, press molding, injection molding, gas-assisted injection molding, welding molding, extrusion molding, blow molding, film molding, hollow molding, multi-layer molding, and melt spinning. Etc., generally known plastic molding methods can be mentioned.

<Use>
Since the molded product of the present embodiment is obtained from the above-mentioned polyamide composition, it is excellent in water absorption rigidity, thermal rigidity and surface appearance. Therefore, the molded product of the present embodiment can be used as various parts such as automobile parts, electric and electronic parts, home appliance parts, OA (Office Automation) equipment parts, portable equipment parts, industrial equipment parts, daily necessities and household goods. It can be suitably used for extrusion applications and the like. Above all, the molded product of the present embodiment is suitably used as an automobile part, an electric and electronic part, a home electric appliance part, an OA equipment part, or a mobile equipment part.

The automobile parts are not particularly limited, and examples thereof include intake system parts, cooling system parts, fuel system parts, interior parts, exterior parts, electrical component parts, and the like.

The automobile intake system component is not particularly limited, and examples thereof include an air intake manifold, an intercooler inlet, an exhaust pipe cover, an inner bush, a bearing retainer, an engine mount, an engine head cover, a resonator, and a throttle body.
The automobile cooling system component is not particularly limited, and examples thereof include a chain cover, a thermostat housing, an outlet pipe, a radiator tank, an alternator, a delivery pipe, and the like.
The automobile fuel system parts are not particularly limited, and examples thereof include fuel delivery pipes and gasoline tank cases.
The automobile interior parts are not particularly limited, and examples thereof include an instrumental panel, a console box, a glove box, a steering wheel, and a trim.
The automobile exterior parts are not particularly limited, and examples thereof include moldings, lamp housings, front grills, mudguards, side bumpers, door mirror stays, roof rails, and the like.
The automobile electrical components are not particularly limited, and examples thereof include connectors, wire harness connectors, motor components, lamp sockets, sensor in-vehicle switches, combination switches, and the like.

The electric and electronic components are not particularly limited, and examples thereof include connectors, reflectors for light emitting devices, switches, relays, printed wiring boards, electronic component housings, outlets, noise filters, coil bobbins, motor end caps, and the like.
Reflectors for light emitting devices include optical semiconductors such as laser diodes (LDs) in addition to light emitting diodes (LEDs), fott diodes, charge-coupled devices (CCDs), complementary metal oxide semiconductors (CMOS), and other semiconductor packages. Can be widely used in.

The portable device component is not particularly limited, and examples thereof include a housing and a structure of a mobile phone, a smartphone, a personal computer, a portable game device, a digital camera, and the like.

The industrial equipment parts are not particularly limited, and examples thereof include gears, cams, insulating blocks, valves, power tool parts, agricultural machinery parts, engine covers, and the like.

Examples of daily necessities and household items include, but are not limited to, buttons, food containers, office furniture, and the like.

The extrusion application is not particularly limited, but is used, for example, in films, sheets, filaments, tubes, rods, hollow molded products and the like.

Among these various uses, the molded product of the present embodiment is particularly suitable for an exterior structural material. The exterior structural material is a mechanical part or structural part that is required to have surface workability (for example, grain workability, high surface glossiness, etc.) of a molded product and relatively large strength and rigidity.
Specific examples of the structural material for the exterior include OA equipment field supplies, automobile parts, electrical field supplies, and other field supplies.
Examples of OA equipment field supplies include furniture supplies such as desk legs, chair legs, seats, cabins, and wagon parts, notebook computer housings, and the like.
Examples of automobile parts include door mirror stays, wheel rims, wheel caps, wipers, motor fans, seat lock parts, gears, lamp housings, wheel rims, wheel spokes, saddles, saddle posts, handles, stands, loading platforms and the like. ..
Examples of electrical products include pulleys, gears, hot air blower housings, and the like.
Examples of other field products include valve housings, nails, screws, bolts, bolts and nuts.

Further, since the molded product of the present embodiment has an excellent surface appearance, it is also preferably used as a molded product having a coating film formed on the surface of the molded product.
The method for forming the coating film is not particularly limited as long as it is a known method, and for example, coating such as a spray method or an electrostatic coating method can be used.
The paint used for painting is not particularly limited as long as it is known, and for example, a melamine crosslinked type polyester polyol resin paint, an acrylic urethane paint, or the like can be used.
Above all, the molded product of the present embodiment is excellent in mechanical strength, toughness, heat resistance, and vibration fatigue resistance, so that it is more suitable as a component material for automobiles, and further, it is excellent in slidability. , Especially suitable as a component material for gears and bearings. Further, since it is excellent in mechanical strength, toughness, and heat resistance, it is more suitable as a component material for electricity and electronics.

Hereinafter, the present invention will be described in detail 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.
Hereinafter, (A) crystalline polyamide, (B) amorphous semi-aromatic polyamide and (C) carbon fiber used in Examples and Comparative Examples will be described. Example 8 is a reference example.

<Components>
[(A) Crystalline polyamide]
A-1 to A-5: Polyamide 66 (The manufacturing method is as described later)
A-6: Polyamide MXD6 resin "Lenny" (registered trademark) # 6002 (manufactured by Mitsubishi Engineering Plastics Co., Ltd.) (Tm: 238 ° C, Tc: 161 ° C)
A-7: Polyamide 6 SF1013A (manufactured by Ube Industries) (Tm 224 ° C)

[(B) Amorphous semi-aromatic polyamide]
B-1: Polyamide 6I Mw (B) = 35000, Mw (B) / Mn (B) = 2
B-2: Polyamide 6IT-40 (manufactured by LANXESS) Mw (B) = 44000, Mw (B) / Mn (B) = 2.8

[(C) Carbon fiber]
C-1: Carbon fiber HTC413 (manufactured by Toho Tenax)
C-2: Carbon fiber TR60NE (manufactured by Mitsubishi Rayon)

<Method for producing (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide>
[material]
The (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide used in Examples and Comparative Examples were produced by appropriately using the following (a) and (b).
((A) Dicarboxylic acid)
a-1: Adipic acid (ADA) (manufactured by Wako Pure Chemical Industries, Ltd.)
a-2: Isophthalic acid (IPA) (manufactured by Wako Pure Chemical Industries, Ltd.)
((B) Diamine)
b-1: 1,6-diaminohexane (hexamethylenediamine) (C6DA) (manufactured by Tokyo Chemical Industry)

[Synthesis Example 1] Synthesis of Crystalline Polyamide A-1 (Polyamide 66) The polymerization reaction of the polyamide was carried out as follows by the "hydrothermal fusion polymerization method".
First, 1500 g of an equimolar salt of adipic acid and hexamethylenediamine was dissolved in 1500 g of distilled water to prepare an equimolar 50% by mass uniform aqueous solution of the raw material monomer. This aqueous solution was placed in an autoclave having an internal volume of 5.4 L and substituted with nitrogen.
While stirring at a temperature of 110 ° C. or higher and 150 ° C. or lower, water vapor was gradually removed and concentrated to a solution concentration of 70% by mass. After that, the internal temperature was raised to 220 ° C. At this time, the autoclave was boosted to 1.8 MPa. The reaction was carried out for 1 hour as it was until the internal temperature reached 245 ° C., while the water vapor was gradually removed and the pressure was maintained at 1.8 MPa.
Next, the pressure was reduced over 1 hour. Then, the inside of the autoclave was maintained in a vacuum device under a reduced pressure of 650 torr for 10 minutes. At this time, the final internal temperature of the polymerization was 265 ° C.
Then, it was pressurized with nitrogen to form a strand from the lower spun (nozzle), water-cooled, cut, discharged in pellet form, and dried at 100 ° C. in a nitrogen atmosphere for 12 hours to obtain crystalline polyamide A-1. ..
The obtained crystalline polyamide A-1 (polyamide 66) had a weight average molecular weight (Mw) = 35,000 and a weight average molecular weight (Mw (A)) / number average molecular weight (Mn (A)) = 2. The amino terminal group concentration of polyamide A-1 (polyamide 66) was 45 μmol / g, and the carboxy terminal group concentration was 60 μmol / g.

[Synthesis Example 2] Synthesis of Crystalline Polyamide A-2 (Polyamide 66) Same as Synthesis Example 1 except that 900 g of adipic acid is further added to an equimolar 50% by mass uniform aqueous solution of the raw material monomer produced in Synthesis Example 1. The method was used to obtain crystalline polyamide A-2.
The obtained crystalline polyamide A-2 (polyamide 66) had Mw (A) = 35000 and Mw (A) / Mn (A) = 2. The concentration of the amino-terminal group of the crystalline polyamide A-2 (polyamide 66) was 33 μmol / g, and the concentration of the carboxy-terminal group was 107 μmol / g.

[Synthesis Example 3] Synthesis of Crystalline Polyamide A-3 (Polyamide 66) Same as Synthesis Example 1 except that 900 g of hexamethylenediamine is further added to an equimolar 50% by mass uniform aqueous solution of the raw material monomer produced in Synthesis Example 1. To obtain a crystalline polyamide A-3 using the above method.
The obtained crystalline polyamide A-3 (polyamide 66) had Mw = 35000 and Mw / Mn = 2. The concentration of the amino-terminal group of the crystalline polyamide A-3 (polyamide 66) was 78 μmol / g, and the concentration of the carboxy-terminal group was 52 μmol / g.

[Synthesis Example 4] Synthesis of Crystalline Polyamide A-4 (Polyamide 66) The polymerization reaction of the polyamide was carried out as follows by the "hydrothermal fusion polymerization method".
First, 1500 g of an equimolar salt of adipic acid and hexamethylenediamine was dissolved in 1500 g of distilled water to prepare an equimolar 50% by mass uniform aqueous solution of the raw material monomer. This aqueous solution was placed in an autoclave having an internal volume of 5.4 L and substituted with nitrogen.
While stirring at a temperature of 110 ° C. or higher and 150 ° C. or lower, water vapor was gradually removed and concentrated to a solution concentration of 70% by mass. After that, the internal temperature was raised to 220 ° C. At this time, the autoclave was boosted to 1.8 MPa. The reaction was carried out for 1 hour as it was until the internal temperature reached 245 ° C., while the water vapor was gradually removed and the pressure was maintained at 1.8 MPa.
Next, the pressure was reduced over 1 hour. Then, the inside of the autoclave was maintained in a vacuum device under a reduced pressure of 650 torr for 10 minutes. At this time, the final internal temperature of the polymerization was 265 ° C.
Then, it was pressurized with nitrogen to form a strand from the lower spun (nozzle), water-cooled, cut and discharged as a pellet, and dried at 100 ° C. in a nitrogen atmosphere for 12 hours to obtain a polyamide. The obtained polyamide had Mw = 35000 and Mw / Mn = 2. Then, the pellet was solid-phase polymerized at 200 ° C. for 6 hours to obtain a crystalline polyamide A-4.
The obtained crystalline polyamide A-4 (polyamide 66) had Mw (A) = 70000 and Mw (A) / Mn (A) = 3.0. The concentration of the amino-terminal group of the crystalline polyamide A-4 (polyamide 66) was 45 μmol / g, and the concentration of the carboxy-terminal group was 60 μmol / g.

[Synthesis Example 5] Synthesis of Crystalline Polyamide A-5 (Polyamide 66) The polymerization reaction of the polyamide was carried out as follows by the "hydrothermal fusion polymerization method".
First, 1500 g of an equimolar salt of adipic acid and hexamethylenediamine was dissolved in 1500 g of distilled water to prepare an equimolar 50% by mass uniform aqueous solution of the raw material monomer. This aqueous solution was placed in an autoclave having an internal volume of 5.4 L and substituted with nitrogen.
While stirring at a temperature of 110 ° C. or higher and 150 ° C. or lower, water vapor was gradually removed and concentrated to a solution concentration of 70% by mass. After that, the internal temperature was raised to 220 ° C. At this time, the autoclave was boosted to 1.8 MPa. The reaction was carried out for 1 hour as it was until the internal temperature reached 245 ° C., while the water vapor was gradually removed and the pressure was maintained at 1.8 MPa.
Next, the pressure was reduced over 1 hour. Then, the inside of the autoclave was maintained in a vacuum device under a reduced pressure of 650 torr for 5 minutes. At this time, the final internal temperature of the polymerization was 265 ° C.
Then, it was pressurized with nitrogen to form a strand from the lower spun (nozzle), water-cooled, cut and discharged as a pellet, and dried at 100 ° C. in a nitrogen atmosphere for 12 hours to obtain crystalline polyamide A-5. ..
The obtained crystalline polyamide A-5 (polyamide 66) had Mw (A) = 25,000 and Mw (A) / Mn (A) = 2. The concentration of the amino-terminal group of the crystalline polyamide A-5 (polyamide 66) was 60 μmol / g, and the concentration of the carboxy-terminal group was 80 μmol / g.

[Synthesis Example 6] Synthesis of Amorphous Semi-Aromatic Polyamide B-1 (Polyamide 6I) The polymerization reaction of the polyamide was carried out as follows by the "heat melt polymerization method".
First, 1500 g of isophthalic acid and hexamethylenediamine and adipic acid in an excess of 1.5 mol% with respect to the total isophthalic salt component are dissolved in 1500 g of distilled water, and 50% by mass of the raw material monomer is equal. A homogeneous aqueous solution was prepared.
While stirring at a temperature of 110 ° C. or higher and 150 ° C. or lower, water vapor was gradually removed and concentrated to a solution concentration of 70% by mass. After that, the internal temperature was raised to 220 ° C. At this time, the autoclave was boosted to 1.8 MPa. The reaction was carried out for 1 hour as it was until the internal temperature reached 245 ° C., while the water vapor was gradually removed and the pressure was maintained at 1.8 MPa.
Next, the pressure was reduced over 30 minutes. Then, the inside of the autoclave was maintained in a vacuum device under a reduced pressure of 650 torr for 10 minutes. At this time, the final internal temperature of the polymerization was 265 ° C.
After that, it is pressurized with nitrogen to form a strand from the lower spun (nozzle), water-cooled, cut, discharged in pellet form, dried at 100 ° C. in a nitrogen atmosphere for 12 hours, and atypical semi-aromatic polyamide B-. I got 1.
The obtained amorphous semi-aromatic polyamide B-1 (polyamide 6I) had Mw (B) = 35000 and Mw (B) / Mn (B) = 2.

<Physical characteristics and evaluation>
The physical properties of the crystalline polyamides A-1 to A-7, the amorphous aromatic polyamides B-1 to B-2, and each polyamide composition were measured by using the following methods.
In addition, various evaluations were carried out by the following methods using each polyamide composition and each molded product obtained in Examples and Comparative Examples.

[Various properties of (A) crystalline polyamide and (B) amorphous aromatic polyamide]
[Physical characteristics 1] Melting peak temperature Tm2 (melting point), crystallization peak temperature Tc, crystallization enthalpy ΔH
The measurement was performed using a Diamond-DSC manufactured by PERKIN-ELMER according to JIS-K7121. Specifically, the measurements were made as follows.
First, in a nitrogen atmosphere, about 10 mg of each polyamide was heated from room temperature to about 300 ° C. or higher and 350 ° C. or lower depending on the melting point of the sample at a heating rate of 20 ° C./min. The maximum temperature of the endothermic peak (melting peak) that appears at this time was set to Tm1 (° C.). Next, it was kept at the maximum temperature of the temperature rise for 2 minutes. At this maximum temperature, the polyamide was in a molten state. Then, the temperature was lowered to 30 ° C. at a temperature lowering rate of 20 ° C./min. The exothermic peak appearing at this time was defined as the crystallization peak, the crystallization peak temperature was defined as Tc, and the crystallization peak area was defined as the crystallization enthalpy ΔH (J / g). Then, after holding at 30 ° C. for 2 minutes, the temperature was raised from 30 ° C. to about 280 ° C. or higher and 300 ° C. or lower depending on the melting point of the sample at a heating rate of 20 ° C./min. The maximum temperature of the endothermic peak (melting peak) that appears at this time was defined as the melting point Tm2 (° C.).

[Physical characteristics 2] Weight average molecular weight (Mw), number average molecular weight (Mn), molecular weight distribution Mw / Mn
The weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured using gel permeation chromatography (GPC). The measurement conditions were as follows.
(Measurement condition)
Equipment: Tosoh Corporation, HLC-8020,
Solvent: Hexafluoroisopropanol Measured value: PMMA (polymethylmethacrylate) standard sample (manufactured by Polymer Laboratory) conversion

Moreover, the molecular weight distribution Mw / Mn was calculated from the obtained values.

[Physical characteristics 3] Amino-terminal group concentration and carboxy-terminal group concentration of polyamide (1) Amino-terminal group concentration ([NH ₂ ])
The amount of amino terminal bound to the polymer terminal was measured by neutralization titration as follows.
3.0 g of polyamide was dissolved in 100 mL of a 90 mass% phenol aqueous solution, and the obtained solution was titrated with 0.025 N hydrochloric acid to determine the amino terminal amount (μe equivalent / g). The end point was determined from the indicated value of the pH meter.

(2) Carboxylic acid terminal group concentration ([COOH])
The amount of carboxy terminal bound to the polymer terminal was measured by neutralization titration as follows.
4.0 g of polyamide was dissolved in 50 mL of benzyl alcohol, and the obtained solution was titrated with 0.1 N NaOH to determine the carboxy terminal amount (μ equivalent / g). The end point was determined from the discoloration of the phenolphthalein indicator.

[Physical characteristics of polyamide composition]
[Physical characteristics 4] Using a tan δ peak temperature viscoelasticity measurement and analysis device (manufactured by Rheology: DVE-V4) of the polyamide composition, the parallel portion of the ASTM D1822 TYPE L test piece prepared from each polyamide composition was cut into strips. The temperature dispersion spectrum of the dynamic viscoelasticity of the test piece was measured under the following conditions. The dimensions of the test piece were 3.1 mm (width) × 2.9 mm (thickness) × 15 mm (length: distance between gripping tools). The ratio E2 / E1 of the storage elastic modulus E1 and the loss elastic modulus E2 was defined as tan δ, and the highest temperature was defined as the tan δ peak temperature.
(Measurement condition)
Measurement mode: Tensile waveform: Sine wave Frequency: 3.5Hz
Temperature range: 0 ° C or higher and 180 ° C or lower Temperature rise step: 2 ° C / min
Static load: 400g
Displacement amplitude: 0.75 μm

[Evaluation of polyamide composition and molded products]
[Evaluation 1] Surface gloss value The central portion of the flat plate plate molded pieces obtained in Examples and Comparative Examples was measured for 60 degree gloss according to JIS-K7150 using a gloss meter (IG320 manufactured by HORIBA). It was evaluated that the larger the measured value, the better the surface appearance.

[Evaluation 2] Pellet shape The pellet shape of the polyamide compositions obtained in Examples and Comparative Examples was visually confirmed. The evaluation criteria for the pellet shape are as follows. It was evaluated that obtaining pellets with a good shape would lead to an improvement in productivity.
(Evaluation criteria)
5: Pellet with no fluff and substantially uniform shape of columnar 4: Pellet with no fluff and majority of columnar shape with uniform shape 3: Pellet with slight fluff and majority of columnar shape is uniform Shaped pellets 2: Fluffy, columnar, non-uniformly shaped pellets 1: Fluffy, amorphous pellets

[Evaluation 3] Amount of chips The amount of chips in the production of the polyamide composition in Examples and Comparative Examples was visually confirmed. The evaluation criteria for the amount of chips are as follows. It was evaluated that the small amount of chips leads to the improvement of productivity.
(Evaluation criteria)
5: Almost no chips 4: There are some fine chips 3: Fine chips are conspicuous but there are no large chips 2: There are quite a few fine chips and there are some large chips 1: There are quite a few fine chips and large chips

[Evaluation 4] Tensile strength Using the multipurpose test piece A type molded pieces obtained in Examples and Comparative Examples, a tensile test was performed at a tensile speed of 50 mm / min under ISO 527 temperature conditions at 80 ° C. , The tensile yield stress was measured and used as the tensile strength.

[Evaluation 5] Bending strength The multipurpose test piece A type molded pieces obtained in Examples and Comparative Examples were cut to obtain test pieces having a length of 80 mm, a width of 10 mm, and a thickness of 4 mm. Bending strength was measured according to ISO178.

[Evaluation 6] Charpy Impact Strength with Notch The molded pieces of the multipurpose test piece A type obtained in Examples and Comparative Examples were cut to obtain test pieces having a length of 80 mm, a width of 10 mm, and a thickness of 4 mm. Using the test piece, the notched Charpy impact strength (kJ / m ² ) was measured while complying with ISO 179.

<Manufacturing of polyamide composition>
[Examples 1 to 11 and Comparative Examples 1 to 5]
(1) Production of Polyamide Composition Using the above (A) crystalline polyamide, the above (B) amorphous semi-aromatic polyamide, and the above (C) carbon fibers in the types and proportions shown in Table 1 below. , Each polyamide composition was produced by the following method.
The crystalline polyamides A-1 to A-5 and the amorphous aromatic polyamide B-1 synthesized above are dried in a nitrogen stream to adjust the water content to about 0.2% by mass, and then the water content is adjusted to about 0.2% by mass. It was used as a raw material for a polyamide composition.

A twin-screw extruder [ZSK-26MC: manufactured by Coperion (Germany)] was used as an apparatus for producing the polyamide composition.
The twin-screw extruder has an upstream supply port in the first barrel from the upstream side of the extruder, a downstream first supply port in the sixth barrel, and a downstream second supply port in the ninth barrel. Had. Further, in the twin-screw extruder, the extruder length (L1) / screw diameter (D1) 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 the melting point Tm2 + 20 ° C. of each polyamide, the screw rotation speed was set to 250 rpm, and the discharge rate was set to 25 kg / h.

As a specific manufacturing method using the above manufacturing apparatus, (A) crystalline polyamide and (B) amorphous semi-aromatic polyamide are dry-blended and then supplied from the upstream side supply port of the twin-screw extruder. (C) Carbon fiber was supplied from the first supply port on the downstream side of the twin-screw extruder, and the melt-kneaded product extruded from the die head was cooled in a strand shape and pelletized to obtain pellets of each polyamide composition. The obtained pellets of the polyamide composition were dried in a nitrogen stream to reduce the water content in the polyamide composition to 500 ppm or less.

(2) Production of Molded Product 1 (Flat Plate Molded Piece) Next, the pellets of each obtained polyamide composition were subjected to the following conditions using an injection molding machine (NEX50III-5EG, manufactured by Nissei Plastic Industry Co., Ltd.). The injection pressure and injection speed were appropriately adjusted so that the filling time was in the range of 1.6 ± 0.1 seconds, and a flat plate molded piece (6 cm × 9 cm, thickness 2 mm) was manufactured. The surface gloss value of each of the obtained flat plate plate molded pieces was evaluated by the above method. The results are shown in Tables 1 and 2.
(Manufacturing conditions)
Cooling time: 25 seconds Screw rotation speed: 200 rpm
Mold temperature: Tanδ peak temperature + 5 ℃
Cylinder temperature: (Tm2 + 10) ° C or higher (Tm2 + 30) ° C or lower

(3) Production of molded product 2 (molded piece of multipurpose test piece A type) Next, for the pellets of each obtained polyamide composition, an injection molding machine (PS-40E, manufactured by Nissei Plastic Industry Co., Ltd.) was used. According to ISO 3167, each was molded into a multipurpose test piece A type molded piece. Specific molding conditions were set to injection + holding time 25 seconds, cooling time 15 seconds, mold temperature 80 ° C., and molten resin temperature set to the melting peak temperature (Tm2) + 20 ° C. on the high temperature side of the polyamide. The tensile strength, bending strength, and notched Charpy impact strength of each of the obtained multipurpose test piece A-type molded pieces were evaluated by the above method. The results are shown in Tables 1 and 2. Regarding "weight average molecular weight Mw" in Tables 1 and 2, "-" indicates that the measurement has not been performed.

From Tables 1 and 2, the polyamide composition containing (A) crystalline polyamide, (B) amorphous aromatic polyamide and (C) carbon fiber, and (B) amorphous aromatic polyamide is described above (B). B) Carbon contains 75 mol% or more of isophthalic acid units in the total dicarboxylic acid units constituting the amorphous semi-aromatic polyamide, and carbon in the total diamine units constituting the (B) amorphous semi-aromatic polyamide. Polyamide compositions containing 50 mol% or more of diamine units having a number of 4 or more and 10 or less (Examples 1 to 11) have various mechanical properties (tensile strength) as compared with polyamide compositions having no above constitution (Comparative Examples 1 to 5). , Bending strength and notched charmy strength) were excellent, the surface appearance and the shape of the pellets were excellent, and the amount of chips generated was reduced.

Further, from the comparison of polyamide compositions having different contents of crystalline polyamide A-1 (Examples 1 and 9 to 11), as the content of crystalline polyamide A-1 increases, the pellet shape and chips are reduced. The properties and the surface gloss of the molded product tended to be better.

The polyamide composition of the present embodiment has an excellent pellet shape, a reduced amount of chips generated, and a molded product having an excellent surface appearance can be obtained. The molded product of the present embodiment can be suitably used as a molding material for various parts such as for automobiles, electric and electronic products, industrial materials, industrial materials, daily use and household products.

Claims (10)

(A) Crystalline polyamide and
(B) Amorphous semi-aromatic polyamide and
(C) Carbon fiber and
A polyamide composition containing
The (B) amorphous semi-aromatic polyamide contains 75 mol% or more of isophthalic acid units in the total dicarboxylic acid units constituting the (B) amorphous semi-aromatic polyamide, and the (B) non-carbonate. Among all diamine units constituting the crystalline semi-aromatic polyamide, 50 mol% or more of diamine units having 4 or more and 10 or less carbon atoms are contained.
(B) A polyamide composition having a molecular weight distribution Mw (B) / Mn (B) of 2.1 or less for the amorphous semi-aromatic polyamide . The polyamide composition according to claim 1, wherein the tan δ peak temperature is 90 ° C. or higher. The polyamide composition according to claim 1 or 2, wherein the content of the carbon fiber (C) in the polyamide composition is 30% by mass or more and 65% by mass or less. The (A) crystalline polyamide is polyamide 4 (poly α-pyrrolidone), polyamide 6 (polycaproamide), polyamide 11 (polyundecane amide), polyamide 12 (polydodecane amide), polyamide 46 (polytetramethylene adipa). Mid), Polyamide 56 (Polypentamethylene adipamide), Polyamide 66 (Polyhexamethylene adipamide), Polyamide 610 (Polyhexamethylene sebacamide), Polyamide 612 (Polyhexamethylene dodecamide), Polyamide 6T (Poly) The invention according to any one of claims 1 to 3, which is one or more selected from the group consisting of (hexamethylene terephthalamide), polyamide 9T (polynonane methylene terephthalamide), and a copolymerized polyamide containing these as constituents. Polyamide composition. The claim that the content of the (B) amorphous polyamide is 10 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the total amount of the (A) crystalline polyamide and the (B) amorphous semi-aromatic polyamide. The polyamide composition according to any one of 1 to 4. The polyamide composition according to any one of claims 1 to 5, wherein the content mass of the (B) amorphous semi-aromatic polyamide and the (C) carbon fiber satisfies the relationship of the following formula (1).

The polyamide composition according to any one of claims 1 to 6, wherein the polyamide composition has a weight average molecular weight Mw of 15,000 or more and 35,000 or less. The polyamide composition according to any one of claims 1 to 7, wherein the content of the isophthalic acid in the dicarboxylic acid unit in the (B) amorphous semi-aromatic polyamide is 100 mol%. The polyamide composition according to any one of claims 1 to 8, wherein the (B) amorphous semi-aromatic polyamide is polyamide 6I. A molded product obtained by molding the polyamide composition according to any one of claims 1 to 9 .