JPH05331369A - Polyamide resin composition - Google Patents

Abstract

PURPOSE:To obtain a polyamide resin compsn. useful for producing a molded article which simultaneously satisfies the requirements for strengths, stiffness, elongation, impact resistance, and heat resistance. CONSTITUTION:The compsn. contains a polyamide resin, a reinforcement together with or pretreated with a coupling agent, and another thermoplastic resin having reactive groups. The reinforcement and the thermoplastic resin are each independently dispersed homogeneously in the polyamide resin, the mean particle size of the dispersed thermoplastic resin being about 2mum or lower.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyamide resin composition, and more particularly to a polyamide resin composition useful for the production of a molded product that simultaneously satisfies strength, rigidity, elongation, impact resistance and heat resistance. Regarding

[0002]

2. Description of the Related Art Polyamide resin moldings have excellent mechanical properties,
Since it has thermal, chemical, and electrical properties, it has been widely used for applications such as automobile parts, electrical parts, and industrial parts, but it has poor impact properties at low temperatures, so various impact improving resins should be added. Is well known (for example, JP-A-60
-238360). However, this method has a drawback that the impact strength is improved but the strength, rigidity and heat resistance are lowered.
It is possible to add a reinforcing agent to improve the strength, rigidity, and heat resistance in order to prevent the above-mentioned defects, but the effect of improving them is not always sufficient.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides a molded product which simultaneously satisfies strength, rigidity, elongation, impact resistance and heat resistance by specifying the composition and morphology structure of a polyamide resin composition. It tries to make it possible.

[0004]

Means for Solving the Problems As a result of various studies to achieve the above object, the present inventors have found that a polyamide resin, a reinforcing agent and a coupling agent or a reinforcing agent treated with a coupling agent and the above-mentioned polyamide resin are used. Containing a thermoplastic resin having a reactive group, a thermoplastic resin having a reactive functional group other than the reinforcing agent and the polyamide resin are uniformly dispersed in the polyamide resin substantially independently of each other,
The present invention has been completed by finding that a molded product of a polyamide resin composition in which the thermoplastic resin has a dispersed average particle size of about 2 μm or less simultaneously satisfies strength, rigidity, elongation, impact resistance, and heat resistance.

The proportion of components in the polyamide resin composition of the present invention is preferably 2 to 70 parts by weight, more preferably polyamide, with respect to 98 to 30 parts by weight of the polyamide resin, and a thermoplastic resin having a reactive group other than the polyamide resin. The thermoplastic resin having a reactive group other than the polyamide resin is 3 to 45 parts by weight with respect to 97 to 55 parts by weight of the resin, and the total of the polyamide resin and the thermoplastic resin having a reactive group other than the polyamide resin is 95 to 35 parts by weight. 5% toughening agent
It is 65% by weight, preferably 10 to 50% by weight.

The reinforcing agent may be used in combination with the coupling agent or may be treated with the coupling agent.
The amount of coupling agent is 0.05 with respect to 100 parts by weight of the reinforcing agent.
It is preferable that the amount is not less than 0.1 part by weight, preferably not less than 0.1 part by weight.

Further, the composition of the present invention has the following morphology structure. That is, the reinforcing agent and the thermoplastic resin other than the polyamide resin are uniformly dispersed in the polyamide resin substantially independently of each other, and the dispersed average particle diameter of the thermoplastic resin is about 2 μm or less, preferably 0 μm or less. It is less than or equal to 5μ. The reinforcing agent and the thermoplastic resin having a reactive group other than the polyamide resin are dispersed independently of each other. These particles may be partially or locally adhered to each other, but the adhesion in which the thermoplastic resin envelops the periphery of the reinforcing agent is not good.

When the resin composition has such a composition and such a morphology structure, the resin composition can be a molded product which simultaneously satisfies strength, rigidity, elongation, impact resistance and heat resistance.

Since the molded product of the polyamide resin composition of the present invention simultaneously satisfies strength, rigidity, elongation, impact resistance and heat resistance, it is preferably used in application fields where these properties are particularly required. For example, it is used for outer coating of automobiles, outer panels, interior parts, specifically for fenders, air intiques, foil caps, spoilers, door handles, etc., and also for electric tool parts, electric parts, industrial parts, etc. It is not limited to these.

The polyamide resin in the present invention has an acid amide bond (-CONH-) in the molecule, and more specifically, ε-caprolactam, 6-aminocaproic acid, ω-enanthlactam, 7-amino. Heptanoic acid, 11-aminoundecanoic acid, 9-aminononanoic acid,
Polymers or copolymers obtained from α-pyrrolidone, α-piperidone, etc .: Hexamethylenediamine, nonamethylenediamine, undecamethylenediamine, dodecamethylenediamine, metaxylylenediamine and other diamines and terephthalic acid, isophthalic acid, adipine Examples thereof include polymers or copolymers obtained by polycondensing an acid or a dicarboxylic acid such as sebacic acid, or blends thereof, but are not limited thereto.

Of the above polyamide resins, those having an average molecular weight of 9000 to 30,000 are preferred. Also, the amino terminal group and the carboxyl terminal group of the polyamide resin react with the coupling agent of the reinforcing agent and the polymer having a reactive group other than the polyamide resin to bond with each other, so that the amino terminal group amount and the carboxyl terminal group amount are preferably large. .. Further, the balance of the amount of both terminal groups may be changed depending on the type and amount of the coupling agent used and the type and amount of the reactive group of the polymer having a reactive group other than the polyamide resin.

The reinforcing agents used in the present invention include fibrous reinforcing agents and filler-like reinforcing agents. The fibrous reinforcing agents include glass fiber, and the filler-like reinforcing agents include talc, mica, wollastonite, calcium carbonate and whiskers. ,
Examples thereof include silica, kaolin, montmorillonite, clay and the like, but the present invention is not particularly limited thereto. These reinforcing agents are 95% to 35% by weight of a polyamide resin and a thermoplastic resin having a reactive group other than the polyamide resin.
5 to 65% by weight, preferably 10 to 50% by weight. When the amount of the reinforcing agent is 5% by weight or less, the reinforcing effect is small, and when it is 65% by weight or more, the molded product becomes sloppy, the fluidity at the time of molding is poor, and the appearance of the molded product is poor, which is not preferable.

In order to improve the bond between the reinforcing agent and the polyamide resin, the reinforcing agent may be used in combination with the coupling agent or may be treated with the coupling agent. The coupling agent may be a silane coupling agent or a titanate type coupling agent. Any of a coupling agent, an aluminum-based coupling agent and the like may be used, and among these, an aminosilane coupling agent and an epoxysilane coupling agent are particularly preferable. These silane coupling agents react with the carboxyl terminal group of the polyamide resin, or the amino terminal group to chemically bond the reinforcing agent and the polyamide resin, strength, elastic modulus, elongation,
It works to improve impact resistance. The amount of the coupling agent added is 0.05 parts by weight or more, preferably 0.1 parts by weight or more, based on 100 parts by weight of the reinforcing agent.

As the thermoplastic resin having a reactive group other than the polyamide resin in the present invention, polyethylene (P
E), polypropylene (PP), polymethylpentene (TPX), ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), ethylene-ethyl acrylate copolymer (EEA), ethylene-
Polyolefin resins such as methyl acrylate copolymer (EMA), ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ethylene-vinyl acetate copolymer (EVA); AS resin , AB
S resin, polystyrene (PS), acrylic ester copolymer, styrene-butadiene-styrene block copolymer (SBS), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-isoprene-styrene block copolymer Vinyl polymer resins such as polymer (SIS) and styrene-acrylonitrile copolymer; polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polycarbonate (P
C), polyacrylate (PAR), block copolymer of polybutylene terephthalate (PBT) and polytetramethylene glycol (PTMG), polyester resin such as block copolymer of polybutylene terephthalate (PBT) and polycaprolactone; poly There are resins such as phenylene oxide (PPO), but the resin is not limited to these. Two or more of these thermoplastic resins may be used in combination.

The reactive group contained in the thermoplastic resin other than the polyamide resin in the present invention is a group capable of reacting with the amino group, the carboxyl group and the main chain amide group which are the terminal groups of the polyamide resin. Examples thereof include an acid group, an acid anhydride group, an epoxy group, an oxazoline group, an amino group, and an isocyanate group. Among these, the acid anhydride group has the highest reactivity. There is also a report that the thermoplastic resin having a reactive group that reacts with the polyamide resin is finely dispersed in the polyamide and the distance between the particles is shortened due to the fine dispersion, which greatly improves the impact resistance. S,
Wu: Polymer 26, 1855 (1985)].

As the morphology structure of the composition of the present invention, the reinforcing agent and the thermoplastic resin having a reactive group other than the polyamide resin are substantially independent of each other and uniformly finely dispersed in the polyamide resin (almost all particles are present). Diameter is about 2μ
It is necessary that the thermoplastic resin having a reactive group other than the polyamide resin is in an adhesive state in which the periphery of the reinforcing agent is directly dented.

Unless the reinforcing agent is uniformly dispersed in the polyamide resin, the strength, rigidity, elongation and impact resistance are lowered, which is not preferable. The finely dispersed particle size of the thermoplastic resin having a reactive group other than the polyamide resin in the polyamide resin is about 2 μm or less on average, and preferably 0.5 μ or less. If it is about 2 μm or more, the distance between particles becomes long, and the strength, elongation, and impact resistance decrease, which is not preferable. A thermoplastic resin having a reactive group other than the reinforcing agent and the polyamide resin has good partial or local adhesion, but adhesion with the reinforcing agent embedded therein is not preferable. If adhesion that encloses the reinforcing agent occurs, the purpose of adding the reinforcing agent is to weaken the effect of improving strength, rigidity and heat resistance. Also, a thermoplastic resin having a reactive group other than the polyamide resin being added is incorporated into the polyamide resin. There is a drawback that the amount and number of finely dispersed particles are small (they are taken around the reinforcing agent), the distance between the particles is large, and the impact resistance is lowered.

The resin composition having the morphology structure as described above is simply extruded after blending a polyamide resin, a reinforcing agent and a coupling agent or a coupling agent-treated reinforcing agent, and a thermoplastic resin having a reactive group other than the polyamide resin. It is difficult to obtain by the usual method of melt-kneading with a machine, and it is recommended to use a special method. That is, a polyamide resin and a thermoplastic resin having a reactive group other than the polyamide resin are uniformly melt-kneaded in a melt kneader (for example, a melt extruder or a melting reaction kettle), and the thermoplastic resin is uniformly finely dispersed in the polyamide resin. After that, a reinforcing agent (and a coupling agent) or a coupling agent-treated reinforcing agent is added to uniformly disperse the reinforcing agent in the polyamide resin. Alternatively, after the polyamide resin and the reinforcing agent (and the coupling agent) or the coupling agent-treated reinforcing agent are melt-kneaded by a melt-kneading machine and the reinforcing agent is uniformly dispersed in the polyamide resin, a reactive group other than the polyamide resin is contained. A thermoplastic resin is added and the thermoplastic resin is finely dispersed uniformly in the polyamide resin. However, the preparation of the polyamide composition of the present invention is not limited to such a specific blending method, and other blending methods can of course be used as long as the above composition and morphology structure are obtained.

The polyamide resin composition of the present invention contains a flame retardant, a release agent, a light or heat stabilizer, and a stabilizer according to various purposes.
A colorant or the like can be added. The flame retardant is preferably a combination of a halogen-based flame retardant and antimony trioxide, and the halogen-based flame retardant is preferably brominated polystyrene, polydibromophenylene oxide, decabromodiphenyl ether or the like. As the non-halogen flame retardant, melamine cyanurate, red phosphorus and the like are preferable. As the release agent, a metal salt of stearic acid or the like is preferable. As the light or heat stabilizer, carbon black, a combination of copper halide and potassium halide, a hindered phenol type stabilizer, a phosphorus type stabilizer and a combination thereof are preferable. However, it is not limited to these.

[0020]

EXAMPLES Next, the present invention will be described more specifically by showing Examples and Comparative Examples, but it goes without saying that the present invention is not limited to these Examples.・ Resin used Polyamide resin: Nylon 6 Toyobo Co., Ltd., brand T
-803 (molecular weight = 16000, amino terminal weight = 58me
q / Kg, carboxy terminal amount = 58 meq / Kg) Polyamide resin: Nylon 66 Toyobo Co., Ltd., brand T-662 (amino terminal amount 48 meq / Kg, carboxyl terminal amount 48 meq / Kg) Polyolefin resin: polypropylene (PP) Vinyl polymer resin: SEBS Asahi Kasei Corporation
Brand Tuftec H1052 Introducing reactive groups: To 100 parts by weight of PP and SEBS respectively, 1.5 parts by weight of maleic anhydride and 0.3 parts by weight of Perkmill D (F) as a peroxide were added respectively, and the mixture of the two kinds was added. The mixture was extruded with a 35φ twin-screw extruder, cooled, and then cut to prepare pellets of acid-modified PP and acid-modified SEBS.・ Use strengthening agent Wollastonite: Kinsei Kogyo Co., Ltd., brand KTK, average particle size D ₅₀ ≈ 3 μ (0.5 to 8 μ) Talc: Hayashi Kasei Co., Ltd., brand micron 406, average particle size D ₅₀ = 4 ~ 6μ Glass fiber: Asahi Fiber Glass Co., Ltd., brand CS03
MA-411 (Aminosilane surface-treated product) -Coupling agent: Aminosilane: Nippon Yunika Co., Ltd., brand A-1100-Physical property evaluation method: Tensile elongation conforms to ASTM D-638, flexural strength flexural modulus is ASTMD- According to 790. Izod impact strength (with notch) is ASTM D-
According to 256. Heat distortion temperature (4.6 Kg / m ² load)
Conforms to ASTM D-648.・ Morphology observation method for molded products Observation of cross section of tensile test piece Device: Field emission scanning electron microscope (Hitachi S-800
Type) Measuring conditions: Accelerating voltage 6KV Sample preparation: Polishing method, Phosphotungstic acid (PTA) staining

Comparative Examples 1-8, Examples 1-2 As the polyamide resin, Toyobo nylon 6T-803 or nylon 66T-662 (abbreviation PA) is used, and as the thermoplastic resin other than the polyamide resin, SEBS (abbreviation P) is used.
, Acid-modified SEBS (abbreviation MP) or acid-modified PP as a thermoplastic resin having a reactive group other than polyamide resin, and wollastonite (abbreviation KW) as a reinforcing agent,
Talc or glass fiber (abbreviation GF) is used, and the coupling agent is an aminosilane coupling agent (abbreviation C)
Using a Toshiba twin-screw extruder, pellets of a polyamide composition having the composition shown in Table 1 were obtained. The pellets were dried in a vacuum dryer at 80 ° C. for 16 hours and injection-molded to prepare test pieces. Using this test piece, the morphology morphology of the molded product was observed and the relationship between the resin properties [flexural strength, flexural modulus, tensile elongation, Izod impact strength (with notch), heat distortion temperature] was investigated and the results are shown in Table 1. It was shown to.

In Comparative Example 1, PA was charged from the extruder hopper port and melt-kneaded.

In Comparative Example 2, PA and MP were simultaneously blended and then charged from the extruder hopper port to carry out melt-kneading. Compared with Comparative Example 1, the resin characteristic values were improved in Izod impact and elongation, but were decreased in strength, elastic modulus and heat deformation temperature.
Regarding the morphology structure of the molded product, MP was finely dispersed (about 0.1 μ) in PA and adhered.

In Comparative Example 3, PA, KW and C were blended at the same time and then charged from the hopper port of the extruder to carry out melt-kneading.
Compared with Comparative Example 1, the resin characteristic values were significantly improved in strength, elastic modulus and heat distortion temperature, but elongation and Izod impact were lowered. In the morphology structure of the molded product, KW was uniformly dispersed and adhered in PA.

In Comparative Example 4, PA, KW, C and P were blended at the same time and then charged from the hopper port of the extruder to carry out melt-kneading. This resin property value improves the elastic modulus and heat distortion temperature due to the addition of the reinforcing agent, but the Izod impact and the elongation are decreased despite the addition of P. As for the morphology structure of the molded product, KW is dispersed and adhered in PA, but P is finely dispersed (2
The particle size was 5 μm to 70 μm. It is considered that the reason for this is that P does not finely disperse because it does not contain a reactive group that reacts with PA, and elongation and Izod impact are reduced because it does not finely disperse.

In Example 1, PA and MP were blended at the same time, charged from the extruder hopper port, PA and MP were melt-kneaded, and MP was finely dispersed in PA (dispersion average particle size = 0.1 μ). KW and C were added from the middle, and melt kneading was carried out and extruded. The resin characteristic values are strength, elastic modulus, elongation,
It had excellent properties in all of Izod impact and heat distortion temperature. The strength, elastic modulus, and heat distortion temperature retain almost the characteristics of KW addition (Comparative Example 3), and the Izod impact is MP.
Characteristic of addition (comparative example 2) It shows the above effects, KW, MP
Addition (Comparative Examples 2 and 3) maintained excellent characteristics of both.
As shown in the photograph of FIG. 1, the morphology structure of the molded product was such that MP was finely dispersed and adhered in PA with a particle diameter of about 0.1 μ, and the distance between MP particles was about 0.1 to 0.3 μ. .. KW in PA was directly dispersed and adhered to PA, and MP was not adhered around KW. In the photograph of FIG. 1, the white part is PA of the matrix, the black part (dots) is SEBS (MP), and the intermediate color part is wollastonite (KW) of the reinforcing agent.

In Example 2, PA, KW and C were blended at the same time, charged from the extruder hopper port, PA, KW and C were melted and kneaded to disperse and bond KW in PA, and then MP was applied from the middle of the extruder.
Was added, melt kneading was performed, and the mixture was extruded. The resin characteristics and the morphology structure of the molded product were almost the same as those of Example 1.

In Comparative Example 5, all of PA, KW, MP and C were blended at the same time and then charged from the extruder hopper port,
PA, KW, MP and C were melt-kneaded and extruded. With respect to the resin characteristic values, the strength, elastic modulus and heat distortion temperature were significantly lowered, and the Izod impact was slightly lowered. The morphology structure of the molded product is MP in PA as shown in the photographs of FIGS. 2 and 3.
The particle size was about 0.1 to 0.5 .mu., Which was finely dispersed and adhered, but was slightly larger than in Examples 1 and 2. Further, the distance between particles was around 0.2 to 1 μm, which was about three times wider than in Examples 1 and 2. As a cause of this, MP around the KW
It is conceivable that the particle size was increased due to the uneven distribution of the squid crust MP. It is considered that the strength, elastic modulus, and heat distortion temperature were significantly lowered because MP, which surrounds KW, lowered the original purpose of KW addition, that is, the effect of improving strength, elastic modulus, and heat distortion temperature.

In Comparative Example 6, PA, MP and C were blended at the same time and then charged from the hopper port of the extruder, and PA, MP and C were melt-kneaded, and then KW was charged from the middle of the extruder to further melt-knead and extrude. With respect to the resin characteristic values, strength, elongation, and Izod impact were considerably lowered, and elastic modulus and heat deformation temperature were slightly lowered. As for the morphology structure of the molded product, as shown in the photograph of FIG. 4, the particle size of MP in PA is often around 0.2 to 0.4 μm, in which a coarse particle size of around 15 μm is also observed. It was considerably larger than that of 2. The distance between particles is 1
It was about 2 μ, which was about 10 times wider than in Examples 1 and 2. KW in PA is dispersed but K
A void is formed around W, and the adhesiveness is poor. Such a morphological structure was obtained by blending PA, MP, and C at the same time, and then adding and kneading them from the extruder hopper to carry out melt-kneading, and a non-hydroxyl group which is a reactive group of MP and an amino group which is a reactive group of C It is considered that the two react with each other and do not achieve their original purpose (reaction with PA) and are considerably deactivated. Originally, the acid anhydride group, which is a reactive group of MP, reacts with the amino terminal group of PA, MP is finely dispersed and adhered in PA, and it functions to improve elongation and Izod impact. The amino group, which is a reactive group in C, reacts with the carboxyl terminal groups of KW and PA to chemically bond (bond with each other) PA and KW to improve strength, elastic modulus and elongation.

In Comparative Example 7, after MP and C were blended at the same time, they were charged from the extruder hopper port, MP and C were melted and kneaded, PA and KW were charged from the middle of the extruder, and further melt kneaded and extruded. With respect to this resin characteristic value, strength, elongation, and Izod impact were significantly reduced. The morphology structure of the molded product is good as in Comparative Example 6, but the KW-PA adhesion is even worse, and many KW dropouts are observed during morphology observation.

In the composition of Comparative Example 8, the morphology structure of the molded product was such that the reinforcing agent was dispersed in PA, but the surrounding area was covered with a large amount of SEBS (particle size 10 to 70 μ), which was finely dispersed. There was almost no SEBS. Therefore, the resin characteristic value was inferior.

[0032]

[Table 1]

Examples 3 to 5 and Comparative Examples 9 to 10 As a polyamide resin, Toyobo nylon 6T-803 (abbreviation PA) and Toyobo nylon 66T-662 (abbreviation PA,
NY-66, Example 3 only), polypropylene (abbreviation P)
P), acid-modified PP, talc or glass fiber (abbreviated as GE) as a reinforcing agent, and a coupling agent, and using the Toshiba twin-screw extruder having the composition shown in Table 2, pellets of the polyamide resin composition are prepared. Obtained. The pellets were dried in a vacuum dryer at 80 ° C. for 16 hours and injection-molded to prepare test pieces. Using this test piece, the morphology morphology of the molded product was observed and the resin properties were evaluated. The results are shown in Table 2.

In Examples 3, 4 and 5, Example 1 was used.
According to the blending method according to. Regarding the morphology structure, in all of the examples, the reinforcing agent was uniformly dispersed and adhered in the polyamide resin, and PP was also fine particles (Example 3).
And 5, the average is about 0.3 μ, and in Example 4, the average is about 0.5 μ.
μ) was uniformly dispersed in the polyamide resin, and PP was hardly present around the reinforcing agent.

In Comparative Example 9, the blending method according to Comparative Example 4 was used. Regarding the morphology structure, the reinforcing agent was dispersed in the polyamide resin, but PP was overlaid around it and was not in a state of being directly bonded to the polyamide resin. The PP particles are about 0.5
It was dispersed and adhered in a polyamide resin with a particle size of ˜2 μm.

In Comparative Example 10, the blending method according to Example 4 was used (however, acid-modified PP was not used). Regarding the morphology structure, the reinforcing agent was dispersed and adhered in the polyamide resin, but PP was not finely dispersed and was present in the polyamide resin as coarse particles having a particle size of 10 to 80 μm.

[0037]

[Table 2]

As is clear from the results shown in Tables 1 and 2, the molded products obtained from the polyamide resin composition of the present invention are excellent in strength, rigidity, elongation, impact resistance and heat resistance. I know that there is.

[0039]

As described above, the polyamide resin composition of the present invention contains a polyamide resin, a reinforcing agent and a coupling agent or a coupling agent-treated reinforcing agent, and a thermoplastic resin having a reactive group other than the polyamide resin. The specific morphology in which the reinforcing agent and the thermoplastic resin are substantially finely dispersed in the polyamide resin substantially independently of each other, and the dispersion average particle size of the thermoplastic resin is about 2 μm or less. Since it has a structure, the molded product produced from it has
Excellent in strength, rigidity, elongation, impact resistance and heat resistance.

[Brief description of drawings]

FIG. 1 is an electron micrograph (magnification × 10000) showing a cross-sectional structure of a molded product obtained from the resin composition of Example 1.

FIG. 2 is an electron micrograph (magnification × 10000) showing a cross-sectional structure of a molded product obtained from the resin composition of Comparative Example 5.

3 is an electron micrograph (magnification × 100) showing the cross-sectional structure of the other part of the molded article obtained from the resin composition of Comparative Example 5.
00).

FIG. 4 is an electron micrograph (magnification × 10000) showing a cross-sectional structure of a molded product obtained from the resin composition of Comparative Example 6.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location C08L 101/00 LTA 7242-4J

Claims (1)

[Claims] 1. A composition comprising a polyamide resin, a reinforcing agent and a coupling agent or a coupling agent-treated reinforcing agent, and a thermoplastic resin having a reactive functional group other than the polyamide resin, the reinforcing agent comprising: A thermoplastic resin having a reactive functional group other than the polyamide resin is uniformly dispersed in the polyamide resin substantially independently of each other, and the dispersion average particle diameter of the thermoplastic resin is about 2 μm or less. And a polyamide resin composition.