JP7087716B2 - Polyamide resin composite molded product and its manufacturing method - Google Patents

Description

The present invention relates to a polyamide resin composite molded product having a fiber-reinforced polyamide resin base material and a polyamide resin molded product, and a method for producing the same.

Polyamide resins have excellent mechanical properties, heat resistance, and chemical resistance, and are therefore preferably used in automobiles and electric / electronic component applications. In particular, fiber-reinforced polyamide resins reinforced with glass fibers, carbon fibers, etc. can significantly improve their mechanical properties as compared with other thermoplastic resins, and development of metal alternative applications is underway. Further, in recent years, it is expected to be applied to structural members having a large contribution to the vehicle weight, and further improvement of mechanical characteristics is required.

As a technique for further improving the mechanical properties of a thermoplastic resin molded product such as a polyamide resin, there is a method of combining a fiber reinforced resin base material containing continuous reinforcing fibers and an injection molded product.

From the viewpoint of lowering the molding processing temperature and shortening the molding cycle, it is required to develop a polyamide resin material for continuously reinforced base materials, which has excellent molding processability and mechanical properties, which contributes to reduction of environmental load and energy cost. ing. Generally, it is known that the mechanical properties improve as the molecular weight of the polyamide resin increases, but at the same time, the melt fluidity of the polyamide resin also decreases, so that the molding processability deteriorates. rice field. Although the melt fluidity can be improved by raising the molding temperature, the thermal stability is lowered, and the molecular weight is lowered and the thermal decomposition accompanied by gas generation occurs during the molding, so that the mechanical properties and the appearance of the molded product are obtained. There was a problem such as a decrease in.

So far, as a method for improving the thermal stability of the polyamide resin, for example, by sealing the amino-terminal group and the carboxyl-terminal group of the polyamide resin with acetic acid and diazomethane, respectively, thermal decomposition from the polyamide resin terminal is suppressed. A method has been proposed (see, for example, Non-Patent Document 1). Although it is possible to improve the thermal stability and raise the molding processing temperature by such a technique, the melt viscosity is still high, and the molding processing is made in response to the recent demands for miniaturization, complexity, thinning, and weight reduction of molded products. There was a problem of insufficient sex.

As a composite material for structural materials having excellent formability and mechanical properties, for example, a carbon fiber reinforced polyamide resin prepreg (for example, Patent Document 1) containing carbon fibers in a polyamide resin is known.

Further, as a polyamide resin having excellent mechanical properties and fluidity, a polyamide resin having a hydrocarbon group having 6 to 22 carbon atoms and having a relative viscosity of 2 or more and less than 2.5 has been proposed (for example, Patent Document 2). reference). However, the polyamide resin still has a high melt viscosity, and there is a problem that the molding processability is insufficient in response to the recent demands for miniaturization, complexity, thinning, and weight reduction of molded products. On the other hand, as a high molecular weight terminal-modified polyamide resin having excellent formability and crystallinity, it contains 0.5 to 4.5% by mass of a specific terminal structure and has a relative viscosity ηr of 2.1 to 2. A terminal-modified polyamide resin of No. 10 has been proposed (see, for example, Patent Document 3).

Japanese Unexamined Patent Publication No. 2013-159675 Japanese Unexamined Patent Publication No. 6-145345 International Publication No. 2015/182693

"Journal of Science (J. Polymer. Sci.)", PRAGUE SYSTEMSIUM, 1958, Vol. 30, p. 459-478

Although the solidification can be delayed only by controlling the crystallinity described in Patent Document 1, the viscosity of the resin cannot be lowered, and the improvement effect is limited.

Further, although the terminal-modified polyamide resin described in Patent Document 3 has excellent melt fluidity, the polyalkylene oxide structure is introduced into the polyamide resin and at the same time the carboxyl terminal group is blocked by the monoamine compound having a polyalkylene oxide structure. On the other hand, since the amino terminal group is not sealed at all, thermal decomposition from the amino terminal group and thermal decomposition of the polyalkylene oxide structure are promoted during melt retention such as during molding, and the effect of melt fluidity due to polyalkylene oxide modification is achieved. There was a problem that the

An object of the present invention is to provide a polyamide resin composite molded body having excellent melt fluidity and thermal stability during melt retention and having little variation in characteristics.

In order to solve the above problems, the present invention mainly has the following configurations.
[1] A composite molded product obtained by bonding a fiber-reinforced polyamide resin base material obtained by impregnating a reinforcing fiber base material with a polyamide resin for impregnation and a polyamide resin molded product containing the polyamide resin at least in part.
The terminal-modified polyamide resin in which the impregnating polyamide resin has a structure in which at least a part of the polymer constituting the polyamide resin is composed of structural units different from the repeating structural units constituting the main chain of the polymer at the terminal group of the polymer. And
A composite molded product made of a polyamide resin, wherein the melting point of the polyamide resin for impregnation is equal to or lower than the melting point of the polyamide resin in the polyamide resin molded product.
[2] The polyamide resin composite molded product according to [1], wherein the terminal-modified polyamide resin contains 1 to 20% by mass of a terminal structure represented by the following general formula (I).
-X- (R ¹ -O) _m -R ² (I)
In the above general formula (I), m represents a range of 2 to 100. R ¹ represents a divalent hydrocarbon group having 2 to 10 carbon atoms, and R ² represents a monovalent hydrocarbon group having 1 to 30 carbon atoms. -X- represents -NH-, -N (CH ₃ )-or-(C = O)-. The m R1s included in the general formula ( ^I ) may be the same or different.
[3] The polyamide resin composite molded product according to [2], wherein the terminal-modified polyamide resin further contains 0.1 to 5% by mass of the terminal structure represented by the following general formula (II).
-YR ³ (II)
In the above general formula (II), R ³ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms. When X in the general formula (I) is -NH- or -N (CH ₃ )-, -Y- in the general formula (II) represents-(C = O)-, and the general formula (I) When X in-(C = O)-, Y in the above general formula (II) represents -NH- or -N (CH ₃ )-.
[4] The composite molded product made of a polyamide resin according to any one of [1] to [3], wherein the melting point of the terminal-modified polyamide resin is 15 degrees or more lower than the melting point of the polyamide resin in the polyamide resin molded product.
[5] The polyamide resin molded product contains at least a polyamide resin and a filler, and the content thereof is any one of [1] to [4], wherein the content is 10 to 250 parts by weight of the filler with respect to 100 parts by weight of the polyamide resin. The polyamide resin composite molded product described in 1.
[6] The composite molded product made of a polyamide resin according to any one of [1] to [5], which comprises continuous reinforcing fibers in which the reinforcing fiber base materials are arranged in one direction.
[7] The polyamide resin composite molded product according to [6], wherein the reinforcing fiber is a carbon fiber and the fiber content in the fiber-reinforced polyamide resin base material is 10 to 70% by volume.
[8] Made of a polyamide resin in which a fiber-reinforced polyamide resin base material in which a reinforcing fiber base material is impregnated with an impregnating polyamide resin is placed in a mold in advance, and a polyamide resin composition is injection-molded into the mold to be melt-bonded. In the method for producing a composite molded product, a structure in which at least a part of the polymer constituting the polyamide resin for impregnation is composed of structural units different from the repeating structural units constituting the main chain of the polymer is used as the terminal group of the polymer. A method for producing a composite molded product made of a polyamide resin, which is a terminal-modified polyamide resin and has a melting point of the polyamide resin for impregnation lower than the melting point of the polyamide resin in the polyamide resin composition.
[9] The method for producing a composite molded product made of a polyamide resin according to [8], wherein the polyamide resin composition contains 10 to 250 parts by weight of a filler with respect to 100 parts by weight of the polyamide resin.
[10] The method for producing a polyamide resin composite molded product according to [8] or [9], wherein the melting point of the terminal-modified polyamide resin is 15 degrees or more lower than the melting point of the polyamide resin in the polyamide resin composition.
[11] The method for producing a composite molded product made of a polyamide resin according to any one of [8] to [10], which comprises continuous reinforcing fibers in which the reinforcing fiber base materials are arranged in one direction.
[12] The method for producing a polyamide resin composite molded product according to [11], wherein the reinforcing fiber is a carbon fiber and the fiber content in the fiber-reinforced polyamide resin base material is 10 to 70% by volume.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a polyamide resin composite molded product having high mechanical properties and little variation in the properties, and a method for producing the same.

Hereinafter, embodiments of the present invention will be described in detail.

The polyamide resin composite molded product according to the embodiment of the present invention includes a fiber-reinforced polyamide resin base material and a polyamide resin molded product. The fiber-reinforced polyamide resin base material is obtained by impregnating a reinforced fiber base material with a polyamide resin for impregnation.

[Fiber reinforced polyamide resin base material]
The fiber-reinforced polyamide resin base material of the embodiment of the present invention has one of the following two aspects. The first aspect is a fiber-reinforced polyamide resin base material obtained by impregnating continuous reinforcing fibers with a polyamide resin for impregnation described later, and the second aspect is a reinforcing fiber base material in which reinforcing fibers of discontinuous fibers are dispersed. , A fiber-reinforced polyamide resin base material impregnated with a polyamide resin for impregnation, which will be described later.

The impregnating polyamide resin in the present invention has a terminal having a structure in which at least a part of the polymer constituting the polyamide resin is composed of structural units different from the repeating structural units constituting the main chain of the polymer at the end of the polymer. It is a modified polyamide resin. Hereinafter, the polyamide resin for impregnation may be referred to as a terminal-modified polyamide resin.

In the embodiment of the present invention, the continuous reinforcing fiber in the first aspect means that the reinforcing fiber is continuous in the fiber-reinforced polyamide resin base material. Examples of the form and arrangement of the reinforcing fibers in the embodiment of the present invention include those aligned in one direction, woven fabric (cloth), knitting, braid, tow and the like. Above all, it is preferable that the reinforcing fibers are arranged in one direction because the mechanical properties in a specific direction can be efficiently enhanced.

The reinforcing fiber base material in which the discontinuous fibers are dispersed in the second aspect means a mat-like material in which the reinforcing fibers are cut and dispersed in the fiber-reinforced polyamide resin base material. The reinforcing fiber base material according to the embodiment of the present invention can be obtained by an arbitrary method such as a wet method in which the fibers are dispersed in a solution and then produced in the form of a sheet, or a dry method using a carding device or an airlaid device. can. From the viewpoint of productivity, a dry method using a carding device or an air-laid device is preferable.

The number average fiber length of the discontinuous fibers in the reinforcing fiber base material according to the embodiment of the present invention is preferably 3 to 100 mm. When the number average fiber length of the discontinuous fibers is 3 mm or more, the reinforcing effect of the discontinuous fibers is sufficiently exhibited, and the mechanical strength of the obtained fiber-reinforced polyamide resin base material can be further improved. 5 mm or more is preferable. On the other hand, when the number average fiber length of the discontinuous fibers is 100 mm or less, the fluidity at the time of molding can be further improved. The number average fiber length of the discontinuous fibers is more preferably 50 mm or less, further preferably 30 mm or less.

The number average fiber length of the discontinuous fibers in the fiber-reinforced polyamide resin base material of the embodiment of the present invention can be obtained by the following method. First, a 100 mm × 100 mm sample is cut out from a fiber-reinforced polyamide resin base material, and the cut out sample is heated in an electric furnace at 600 ° C. for 1.5 hours to burn off the matrix resin. From the fiber-reinforced polyamide resin base material thus obtained, 400 discontinuously reinforced fiber bundles are randomly collected. The fiber length of the discontinuous reinforcing fiber bundle taken out can be measured in units of 1 mm using a caliper, and the number average fiber length (Ln) can be calculated by the following equation.

Ln = ΣLi / 400
(Li: Measured fiber length (i = 1, 2, 3, ... 400) (Unit: mm))

The number average fiber length of the discontinuous fibers can be adjusted to the above range by cutting the fibers to a desired length during the production of the reinforcing fiber base material. The orientation of the discontinuous fiber mat is not particularly limited, but it is preferable that the discontinuous fiber mat is isotropically dispersed from the viewpoint of moldability.

The type of the reinforcing fiber in the first and second forms is not particularly limited, and examples thereof include carbon fiber, metal fiber, organic fiber, and inorganic fiber. Two or more of these may be used.

Examples of the carbon fiber include PAN-based carbon fiber made from polyacrylonitrile (PAN) fiber, pitch-based carbon fiber made from petroleum tar or petroleum pitch, and cellulose-based carbon made from viscose rayon or cellulose acetate. Examples thereof include vapor-phase growth-based carbon fibers made from fibers and hydrocarbons, and these graphitized fibers. Among these carbon fibers, PAN-based carbon fibers are preferably used because they have an excellent balance between strength and elastic modulus.

Examples of the metal fiber include fibers made of a metal such as iron, gold, silver, copper, aluminum, brass, and stainless steel.

Examples of the organic fiber include fibers made of an organic material such as aramid, polybenzoxazole (PBO), polyphenylene sulfide, polyester, polyamide, and polyethylene. Examples of the aramid fiber include a para-based aramid fiber having excellent strength and elastic modulus, and a meta-based aramid fiber having excellent flame retardancy and long-term heat resistance. Examples of the para-aramid fiber include polyparaphenylene terephthalamide fiber and copolyparaphenylene-3,4'-oxydiphenylene terephthalamide fiber, and examples of the meta-based aramid fiber include polymethaphenylene isophthalamide fiber. Can be mentioned. As the aramid fiber, a para-type aramid fiber having a higher elastic modulus than the meta-type aramid fiber is preferably used.

Examples of the inorganic fiber include fibers made of an inorganic material such as glass, basalt, silicon carbide, and silicon nitride. Examples of the glass fiber include E glass fiber (for electricity), C glass fiber (for corrosion resistance), S glass fiber, and T glass fiber (high strength and high elasticity). Basalt fiber is a fiber made from basalt, which is a mineral, and has extremely high heat resistance. Basalt generally contains 9-25% by weight of the iron compound FeO or FeO ₂ and 1-6% by weight of the titanium compound TiO or TiO ₂ , but the amount of these components is increased in the molten state. It is also possible to make it into fibers.

Since the fiber-reinforced polyamide resin base material in the first and second embodiments of the present invention is often expected to serve as a reinforcing material, it is desirable to exhibit high mechanical properties, and therefore, to exhibit high mechanical properties. It is preferable that the reinforcing fiber contains carbon fiber.

In the fiber-reinforced polyamide resin base material according to the first and second embodiments of the present invention, the reinforcing fiber is usually composed of one or a plurality of reinforcing fiber bundles in which a large number of single fibers are bundled. The total number of filaments (number of single fibers) of the reinforcing fibers when one or a plurality of reinforcing fiber bundles are arranged is preferably 1,000 to 2,000,000. From the viewpoint of productivity, the total number of filaments of the reinforcing fiber is more preferably 1,000 to 1,000,000, further preferably 1,000 to 600,000, and 1,000 to 300,000. Especially preferable. The upper limit of the total number of filaments of the reinforcing fiber may be such that productivity, dispersibility, and handleability can be kept good in consideration of the balance between dispersibility and handleability.

One reinforcing fiber bundle in the first and second embodiments of the present invention is composed of 1,000 to 50,000 single fibers of reinforcing fibers having an average diameter of 5 to 10 μm.

In the fiber-reinforced polyamide resin base material according to the present invention, the polyamide resin for impregnation impregnated in the reinforced fiber base material of a sheet-like material or a mat-like material satisfies the requirements described later, and is formed by a polyamide resin composition. It can be well welded to the product.

The fiber-reinforced polyamide resin base material according to the first embodiment of the present invention is characterized in that the polyamide resin impregnated in the continuous reinforcing fibers is a terminal-modified polyamide resin. Further, the fiber-reinforced polyamide resin base material according to the second embodiment of the present invention is characterized in that the polyamide resin impregnated in the reinforced fiber base material in which the reinforcing fibers of discontinuous fibers are dispersed is a terminal-modified polyamide resin.

Here, the "terminal-modified polyamide resin" in the present invention is a structure in which at least a part of the polymer constituting the polyamide resin is composed of structural units different from the repeating structural units constituting the main chain of the polymer (hereinafter, Refers to a polyamide resin having a modified structure) at the end group of the polymer. By having a modified structure at the terminal group of the polymer, at least a part of the polymer constituting the polyamide resin reduces the melt viscosity of the polyamide resin while maintaining mechanical properties such as tensile strength and impact resistance. Can be done. Therefore, the impregnation property can be improved even when the processing temperature is moderately low, and the generation of voids in the fiber-reinforced polyamide resin base material can be significantly suppressed. The reason for this is that by having a structure in which at least a part of the polymer constituting the polyamide resin is modified at the end group of the polymer, the polymer has effects such as reduction of intramolecular interaction of polymer chains and increase of free volume. It is thought that this is because the molecular motility of the chain is greatly increased.

The terminal-modified polyamide resin in the embodiment of the present invention is a polyamide resin that can be obtained as a main raw material from one or more selected from amino acids, lactams and "mixtures of diamine and dicarboxylic acid", and constitutes a polyamide resin. At least a portion of the polymer has a modified structure at the end group of the polymer. In other words, the terminal-modified polyamide resin in the present invention is a polyamide resin polymerized using at least one selected from the group consisting of a combination of diamine and dicarboxylic acid, an amino acid, and lactam as a main raw material, and is a polyamide resin. At least a part of the constituent polymer has a modified structure at the terminal group of the polymer. When the amino acid or lactam is used as a raw material, the chemical structure constituting the main structural unit of the polyamide resin is preferably in the range of 4 to 20 carbon atoms. When a diamine and a dicarboxylic acid are used as raw materials, the carbon number of the diamine is preferably in the range of 2 to 20, and the carbon number of the dicarboxylic acid is preferably in the range of 2 to 20. Typical examples of raw materials include the following.

Specifically, amino acids such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, and paraaminomethylbenzoic acid. Lactams such as ε-caprolactam, ω-undecane lactam, and ω-laurolactam. Ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decanediamine, undecanediamine, dodecanediamine, tridecanediamine, tetradecanediamine, pentadecanediamine, hexadecane Diamines such as diamine, heptadecanediamine, octadecanediamine, nonadecandiamine, eikosandiamine, 2-methyl-1,5-diaminopentane, 2-methyl-1,8-diaminooctane; cyclohexanediamine, bis- ( Alicyclic diamines such as 4-aminocyclohexyl) methane and bis (3-methyl-4-aminocyclohexyl) methane; diamines such as aromatic diamines such as xylylene diamine. Aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid; terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, Aromatic dicarboxylic acids such as 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium sulfoisophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid; alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid; Examples thereof include dialkyl esters and dichlorides.

In the embodiment of the present invention, polyamide homopolymers or copolymers derived from these raw materials can be used as the polyamide resin into which the terminal structure is introduced. Two or more kinds of such polyamides may be mixed to form a polyamide resin. In the embodiment of the present invention, the structural unit derived from the raw material exemplified above is modified from the viewpoint of further improving the mechanical properties and thermal stability during melt retention and further reducing the voids caused by the generated gas. It is preferable to have 80 mol% or more, more preferably 90 mol% or more, still more preferably 100 mol%, out of 100 mol% of all structural units constituting the polyamide resin excluding the above-mentioned structure. Further, the polymerization structure derived from the raw material exemplified above is preferably linear.

The melting point (Tm) of the terminal-modified polyamide resin according to the embodiment of the present invention is preferably 190 ° C. or higher. Here, the melting point of the terminal-modified polyamide resin can be determined by differential scanning calorimetry (DSC). The measurement method is as follows. Weigh 5 to 7 mg of the terminal-modified polyamide resin. In a nitrogen atmosphere, the temperature is raised from 20 ° C. to Tm + 30 ° C. at a heating rate of 20 ° C./min. Subsequently, the temperature is lowered to 20 ° C. at a temperature lowering rate of 20 ° C./min. The temperature at the apex of the endothermic peak that appears when the temperature is raised again from 20 ° C. to Tm + 30 ° C. at a heating rate of 20 ° C./min is defined as the melting point (Tm).

Examples of the terminal-modified polyamide resin having a melting point of 190 ° C. or higher include the following polyamides and those having a modified structure at the ends of their copolymers. Two or more of these may be used depending on the required properties such as heat resistance, toughness, and surface properties. Examples of polyamides include polycaproamide (polyamide 6), polyundecaneamide (polyamide 11), polydodecaneamide (polyamide 12), polyhexamethylene adipamide (polyamide 66), polytetramethylene adipamide (polyamide 46), and the like. Polypentamethylene adipamide (polyamide 56), polytetramethylene sebacamide (polyamide 410), polypentamethylene sebacamide (polyamide 510), polyhexamethylene sebacamide (polyamide 610), polyhexamethylene dodecamide (polyhexamethylene dodecamide) Polyamide 612), polydecamethylene sebacamide (nylon 1010), polydecamethylene dodecamide (nylon 1012), polymethoxylylene adipamide (MXD6), polymethoxylylene sevacamide (MXD10), polyparaxylylene Bacamide (PXD10), Polynonamethylene terephthalamide (Nylon 9T), Polydecamethylene terephthalamide (Polyamide 10T), Polyundecamethylene terephthalamide (Polyamide 11T), Polydodecamethylene terephthalamide (Polyamide 12T), Polypentamethylene Telephthalamide / Polyhexamethylene terephthalamide copolymer (polyamide 5T / 6T), poly-2-methylpentamethylene terephthalamide / polyhexamethylene terephthalamide (polyamide M5T / 6T), polyhexamethylene adipamide / polyhexamethylene terephthalamide Copolymer (Polyamide 66 / 6T), Polyhexamethylene adipamide / Polyhexamethylene terephthalamide / Polyhexamethylene isophthalamide (Polyamide 66 / 6T / 6I), Polyhexamethylene adipamide / Polyhexamethylene isophthalamide copolymer (Polyamide) 66 / 6I), polycaproamide / polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (polyamide 6/66 / 6I), polybis (3-methyl-4-aminocyclohexyl) methaneterephthalamide (polyamide MACMT), Polybis (3-methyl-4-aminocyclohexyl) methaneisophthalamide (polyamide MACMI), polybis (3-methyl-4-aminocyclohexyl) methadodecamide (polyamide MACM12), polybis (4-aminocyclohexyl) methaneterephthalamide (polyamide) PACMT), Polybis (4-aminocyclohexyl) methane Examples thereof include isophthalamide (polyamide PACMI) and polybis (4-aminocyclohexyl) methanedodecamide (polyamide PACM12).

Particularly preferred are the ends of polyamide 6, polyamide 66, polyamide 56, polyamide 410, polyamide 510, polyamide 610, polyamide 6/66, polyamide 6/12, polyamide 9T, polyamide 10T, polyamide 6/66 / 6I and the like. , Those having a modified structure can be mentioned.

In the embodiment of the present invention, the modified structure contained in the terminal group of the terminal-modified polyamide is different from the structure derived from the repeating structural unit constituting the main chain of the polymer of the polyamide resin. Examples of the modified structure include structures derived from saturated aliphatic compounds, unsaturated aliphatic compounds, aromatic compounds and the like. Two or more of these may be used. From the viewpoint of further improving the impregnation property and the surface quality, the structure derived from the saturated aliphatic compound or the aromatic compound is more preferable, and the structure derived from the saturated aliphatic compound is further preferable.

Examples of the modified structure in the embodiment of the present invention include residues of the terminal modification compound described later.

The terminal-modified polyamide resin of the embodiment of the present invention preferably has a terminal structure represented by the following general formula (I). Since the terminal structure represented by the following general formula (I) has an alkylene oxide structure, the obtained polymer has high molecular mobility and has excellent affinity with an amide group. The structure represented by the following general formula (I) at the end of the polyamide resin is interposed between the polyamide molecular chains to further increase the free volume of the polymer and further reduce the entanglement. As a result, the molecular mobility of the polymer can be further increased to reduce the melt viscosity, and the impregnation property and the surface quality can be further improved. Such an effect is extremely high as compared with the case where the polyalkylene oxide structure is mainly contained in the main chain of the polyamide resin.

-X- (R ¹ -O) _m -R ² (I)

In the general formula (I), m represents a range of 2 to 100 (2 or more and 100 or less). The larger m is, the more effectively the effect of reducing the melt viscosity is exhibited. The m is preferably 5 or more, more preferably 8 or more, and even more preferably 16 or more. On the other hand, the smaller m is, the higher the heat resistance can be maintained. m is preferably 70 or less, more preferably 50 or less. From the viewpoint of maintaining the characteristics derived from the main structural unit of the polyamide resin, the terminal-modified polyamide resin in the present invention preferably has the structure represented by the above general formula (I) only at the end of the polymer.

In the above general formula (I), R ¹ represents a divalent hydrocarbon group having 2 to 10 carbon atoms (2 or more and 10 or less). From the viewpoint of compatibility with the main structural unit of the polyamide resin, a hydrocarbon group having 2 to 6 carbon atoms is more preferable, and a hydrocarbon group having 2 to 4 carbon atoms is more preferable.

Saturated hydrocarbon groups are more preferred from the viewpoint of thermal stability and color prevention of the terminal-modified polyamide resin. Examples of R ¹ include an ethylene group, a 1,3-trimethylene group, an isopropylene group, a 1,4-tetramethylene group, a 1,5-pentamethylene group, a 1,6-hexamethylene group, and the like. The R ¹ may be a combination of hydrocarbon groups having different carbon atoms. R ¹ is preferably composed of at least a divalent saturated hydrocarbon group having 2 carbon atoms and a divalent saturated hydrocarbon group having 3 carbon atoms. It is more preferably composed of an ethylene group having an excellent affinity with the main structural unit of the polyamide resin and an isopropylene group having a large free volume, and the effect of reducing the melt viscosity can be more effectively exhibited. In this case, the terminal structure represented by the general formula (I) preferably contains 10 or more ethylene groups and 6 or less isopropylene groups, and the terminal structure in an amount close to a desired amount is introduced into the polyamide resin. And the effect of reducing the melt viscosity can be further enhanced. Further, R ² represents a monovalent hydrocarbon group having 1 to 30 carbon atoms (1 or more and 30 or less). Since the smaller the number of carbon atoms in ^R2 , the better the affinity with the main structural unit of the polyamide resin, a hydrocarbon group having 1 to 20 carbon atoms is preferable, and a hydrocarbon group having 1 to 10 carbon atoms is more preferably used. Further, from the viewpoint of thermal stability and color prevention of the terminal-modified polyamide resin, it is more preferable that R ² is a monovalent saturated hydrocarbon group. Examples of R ² include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group and the like, and among them, the main structural unit of the polyamide resin. Methyl and ethyl groups, which have excellent affinity with the above, are more preferable.

In the above general formula (I), -X- represents -NH-, -N (CH ₃ )-or-(C = O)-. Of these, -NH-, which has an excellent affinity with the main structural unit of the polyamide resin, is more preferable.

The terminal-modified polyamide resin of the embodiment of the present invention preferably has a terminal structure represented by the general formula (I) in at least a part of the terminal groups of the polymer constituting the terminal-modified polyamide resin. In other words, the terminal-modified polyamide resin of the present invention preferably has the terminal structure represented by the general formula (I) at at least one end of the polymer constituting the terminal-modified polyamide resin.

The terminal-modified polyamide resin of the embodiment of the present invention contains the terminal structure represented by the general formula (I) in an amount of 1 to 20% by mass (1% by mass or more and 20% by mass or less) in 100% by mass of the terminal-modified polyamide resin. Is preferable. When the content of the terminal structure represented by the general formula (I) is 1% by mass or more, the melt viscosity of the terminal-modified polyamide resin is further reduced, the impregnation property and the surface quality are further improved, and the voids are further reduced. be able to. The content of the terminal structure represented by the general formula (I) is more preferably 3% by mass or more, further preferably 5% by mass or more. On the other hand, when the content of the terminal structure represented by the general formula (I) is 20% by mass or less, the increase in the gas component due to the thermal decomposition of the structure represented by the general formula (I) is suppressed during melting retention. It is possible to further improve the thermal stability during melt retention, further reduce the voids caused by the generated gas, and improve the surface quality. Further, since the molecular weight of the terminal-modified polyamide resin can be increased, the mechanical properties can be further improved. The content of the terminal structure represented by the general formula (I) is more preferably 15% by mass or less, further preferably 10% by mass or less.

In the embodiment of the present invention, the content of the terminal structure represented by the general formula (I) in the terminal-modified polyamide resin is, for example, the general formula (III) described later used when producing the terminal-modified polyamide resin. By adjusting the blending amount of the represented terminal modification compound, it can be adjusted to a desired range.

Further, it is preferable that the terminal-modified polyamide resin of the embodiment of the present invention further has a terminal structure represented by the following general formula (II). As described above, by introducing the terminal structure represented by the general formula (I), the melt viscosity of the terminal-modified polyamide resin can be reduced, and the impregnation property and the surface quality can be improved. During the period of melt retention, the thermal decomposition of the terminal structure represented by the general formula (I) tends to proceed easily. In particular, since the amino terminal group and the carboxyl terminal group of the polyamide resin act as a thermal decomposition catalyst of the terminal structure represented by the general formula (I), the amount of the amino terminal group and the carboxyl terminal group in the polyamide resin should be reduced. As a result, the thermal decomposition of the terminal structure represented by the general formula (I) is suppressed, and the effect of reducing the melt viscosity by the terminal structure represented by the general formula (I) is maintained, while the thermal stability during melt retention is further improved. Can be improved. Therefore, the impregnation property and surface quality can be further improved, and voids can be further reduced. For example, as compared with the case where only the terminal structure represented by the general formula (I) is introduced by reacting the carboxyl terminal group of the polyamide resin with the terminal modification compound represented by the general formula (III) described later. Further, by introducing the terminal structure represented by the following general formula (II) into the amino terminal group, thermal decomposition of the structure represented by the general formula (I) is suppressed, and melting is performed while maintaining the effect of reducing the melt viscosity. The thermal stability during residence can be further improved, voids can be reduced, and surface quality can be improved.

A more specific explanation will be given. For example, by reacting the carboxyl terminal group of the polyamide resin with the compound for terminal modification represented by the general formula (III) described later, a polyamide resin having only the terminal structure represented by the general formula (I) can be obtained. Can be done. However, although one end of the polyamide resin is modified by the terminal structure represented by the general formula (I), the other end is not modified and remains an amino terminal group or a carboxyl group. Therefore, the amino-terminal group or the carboxyl-terminal group acts as a thermal decomposition catalyst of the terminal structure represented by the general formula (I), and the thermal decomposition of the structure represented by the general formula (I) is likely to proceed. Therefore, for example, the polyamide resin (that is, the polyamide resin in which only one end is modified by the structure represented by the general formula (I)) is combined with the terminal modification compound represented by the general formula (IV) described later. By further reacting with the above, the other end can be modified to obtain a polyamide resin further having a terminal structure represented by the following general formula (II). By further introducing the terminal structure represented by the general formula (II) into the polyamide resin modified with the structure represented by the general formula (I), the above-mentioned effect can be obtained.

-YR ³ (II)

In the above general formula (II), R ³ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms (1 or more and 30 or less). The smaller the number of carbon atoms in R3 ^, the better the affinity with the main structural unit of the polyamide resin. Therefore, a hydrocarbon group having 1 to 30 carbon atoms is preferable. Specifically, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, Linear chain such as heptadecyl group, octadecyl group, nonadecil group, icosyl group, eikosyl group, henicosyl group, heneicosyl group, docosyl group, tricosyl group, tetracosyl group, pentacosyl group, hexacosyl group, heptacosyl group, octacosyl group, nonacocil group, triacontyl group. Branched chain alkyl group such as alkyl group, isopropyl group, isobutyl group, tert-butyl group, isopentyl group, neopentyl group, cycloalkyl group such as cyclopentyl group, cyclohexyl group, cycloheptyl group, aryl group such as phenyl group and trill group. , An aralkyl group such as a benzyl group and a 2-phenylethyl group. From the viewpoint of thermal stability and color prevention of the terminal-modified polyamide resin, it is more preferable that R ³ is a saturated hydrocarbon group or aryl group having a monovalent carbon number of 1 or more and 20 or less.

When X in the general formula (I) is -NH- or -N (CH ₃ )-, -Y- in the general formula (II) represents-(C = O)-, and the general formula (I) When X in-(C = O)-, Y in the above general formula (II) represents -NH- or -N (CH ₃ )-.

Usually, the terminal group of the polyamide resin whose both ends are not modified is that one terminal group is an amino terminal group and the other terminal group is a carboxyl terminal group. Here, when the terminal modification compound represented by the general formula (III) has an amino terminal group, the terminal modification compound reacts with the carboxyl terminal group of the polyamide resin, and X in the general formula (I) is -NH. -Or -N (CH ₃ )-. In this case, by reacting the amino-terminal group, which is the other terminal of the polyamide resin, with the terminal-modified compound represented by the general formula (IV), the other terminal of the polyamide resin is reacted with the general formula (II). It can be sealed by the terminal structure of. In this case, Y in the above general formula (II) is − (C = O) −. On the other hand, when the terminal modification compound represented by the general formula (III) has a carboxyl terminal group, the terminal modification compound reacts with the amino terminal group of the polyamide resin, and X in the general formula (I) is − (C). = O)-. In this case, by reacting the carboxyl-terminal group, which is the other terminal of the polyamide resin, with the compound for terminal modification represented by the general formula (IV), the other terminal of the polyamide resin is made to react with the general formula (II). It is closed by the terminal structure of, and Y in the general formula (II) becomes -NH- or -N (CH ₃ )-.

The terminal-modified polyamide resin of the present invention contains the terminal structure represented by the general formula (II) in an amount of 0.1 to 5% by mass (0.1% by mass or more and 5% by mass or less) in 100% by mass of the terminal-modified polyamide resin. Is preferable. When the content of the terminal structure represented by the general formula (II) is 0.1% by mass or more, the thermal decomposition of the structure represented by the general formula (I) in the terminal-modified polyamide resin during melt retention is suppressed. , Thermal stability during melt retention can be further improved, voids can be further reduced, and surface quality can be improved. The content of the terminal structure represented by the general formula (II) is more preferably 0.2% by mass or more, further preferably 0.4% by mass or more. On the other hand, when the content of the terminal structure represented by the general formula (II) is 5% by mass or less, the mechanical properties and the thermal stability at the time of melt retention can be further improved, and the voids can be further reduced. At the same time, the surface quality can be improved. The content of the terminal structure represented by the general formula (II) is more preferably 3% by mass or less, further preferably 1% by mass or less.

In the present invention, the content of the terminal structure represented by the general formula (II) in the terminal-modified polyamide resin is represented by, for example, the general formula (IV) described later used in producing the terminal-modified polyamide resin. By adjusting the blending amount of the terminal modification compound, it can be adjusted to a desired range.

The terminal-modified polyamide resin in the present invention has a terminal structure represented by the general formula (I) and a polyamide resin having a terminal structure represented by the general formula (II) (that is, one end is represented by the general formula (I). It is preferable that the other end is modified with the terminal structure represented by the general formula (II) and is modified with the terminal structure represented by the general formula (II). Polyamide resin having only the terminal structure represented by the general formula (I) (for example, one end is modified with the terminal structure represented by the general formula (I), but the other end is not modified polyamide. Resin) and a polyamide resin having only the terminal structure represented by the general formula (II) (for example, one end is modified with the terminal structure represented by the general formula (II), but the other end is It may be an embodiment containing an unmodified polyamide resin).

Further, in the terminal-modified polyamide resin of the present invention, the content of the terminal structure represented by the general formula (I) [mol / t] and the content of the terminal structure represented by the general formula (II) [mol / t]. It is preferable that the total amount of the above is 60 to 250 mol / t (60 mol / t or more and 250 mol / t or less). By including the terminal structure represented by the general formula (I) and the terminal structure represented by the general formula (II) in a total of 60 mol or more in 1 t of the terminal-modified polyamide resin, the melt viscosity of the terminal-modified polyamide resin is further reduced. The impregnation property can be further improved, the thermal stability during melt retention can be further improved, voids can be further reduced, and the surface quality can be improved. The total content of these terminal structures is more preferably 70 mol / t or more, further preferably 80 mol / t or more. On the other hand, by containing 250 mol or less of the terminal structure represented by the general formula (I) and the terminal structure represented by the general formula (II) in 1t of the terminal-modified polyamide resin, the mechanical properties and thermal stability during melt retention are contained. The properties can be further improved, voids can be further reduced, and surface quality can be improved. The total content of these terminal structures is more preferably 225 mol / t, further preferably 200 mol / t or less.

In the present invention, the total amount of the terminal structure represented by the general formula (I) and the terminal structure represented by the general formula (II) in the terminal-modified polyamide resin is used, for example, when producing the terminal-modified polyamide resin. The desired range can be adjusted by adjusting the blending amounts of the terminal modification compound represented by the general formula (III) described later and the terminal modification compound represented by the general formula (IV).

Further, the terminal-modified polyamide resin of the present invention has a terminal structure content [mol / t] represented by the general formula (I) with respect to the terminal structure content [mol / t] represented by the general formula (II). The ratio ((I) / (II)) of is preferably 0.3 to 2.5. When the polyamide resin is melt-retained, the molecular weight decreases due to thermal decomposition, and at the same time, the molecular weight increases due to the polymerization reaction between the amino-terminal group and the carboxyl-terminal group. It is shown that the more the molar ratio ((I) / (II)) is separated from 1, the larger the difference between the amount of amino terminal groups to be modified (blocked) and the amount of carboxyl terminal groups is, and the larger the difference is. Since the polymerization reaction during melt retention is difficult to proceed and the decrease in molecular weight due to thermal decomposition is larger, the decrease in melt viscosity and molecular weight during melt retention tends to be larger. Further, the larger the difference, the more difficult it is for the polymerization reaction to proceed during melt retention, and the terminal groups (amino terminal groups and carboxyl terminal groups) are not consumed in the polymerization reaction. Therefore, as described above, these terminal groups are represented by the general formula (I). Since it serves as a thermal decomposition catalyst of the terminal structure represented and promotes thermal decomposition of the alkylene oxide structure in the terminal structure represented by the general formula (I), the melt viscosity tends to increase. By setting the molar ratio ((I) / (II)) to 0.3 or more, the melt viscosity of the terminal-modified polyamide resin is further reduced to further improve the impregnation property, and the terminal-modified polyamide resin during melt retention is further improved. Thermal decomposition of the structure represented by the above general formula (I) can be further suppressed, thermal stability can be further improved, voids can be further reduced, and surface quality can be improved. The molar ratio ((I) / (II)) is more preferably 0.5 or more, preferably 0.6 or more, and most preferably 0.8 or more. On the other hand, by setting the molar ratio ((I) / (II)) to 2.5 or less, the thermal decomposition of the terminal structure represented by the general formula (I) in the terminal-modified polyamide resin during melt retention is further suppressed. Therefore, the thermal stability can be further improved, the voids caused by the generated gas can be further reduced, and the surface quality can be improved. The molar ratio ((I) / (II)) is more preferably 2.2 or less, and even more preferably 2.0 or less.

Here, the contents of the terminal structure represented by the general formula (I) and the terminal structure represented by the general formula (II) in the terminal-modified polyamide resin can be determined by ¹ H-NMR measurement, respectively. The measurement method and calculation method are as follows.

First, a deuterated sulfuric acid solution having a polyamide resin concentration of 50 mg / mL is prepared, and ¹ H-NMR measurement is performed by integrating 256 times. Each end structure is derived from the spectral integrated value of R ¹ , the spectral integrated value of R ² , the spectral integrated value of R ³ , and the spectral integrated value of the repeating structural unit (repeated structural unit constituting the main chain of the polymer) of the polyamide resin skeleton. Content (mass% or mol / t) of, and the ratio of the content (mol / t) of the terminal structure (I) to the content (mol / t) of the terminal structure (II) (hereinafter, "molar ratio"). ”) Can be calculated.

In the present invention, the molar ratio ((I) / (II)) in the terminal-modified polyamide resin is, for example, the terminal represented by the general formula (III) described later, which is used when producing the terminal-modified polyamide resin. The compounding ratio of the modification compound and the terminal modification compound represented by the general formula (IV) can be adjusted to a desired range.

The terminal-modified polyamide resin of the present invention preferably contains a total of 50 to 150 mol / t (50 mol / t or more and 150 mol / t or less) of amino-terminal groups and carboxyl-terminal groups. By containing 50 mol or more of these terminal groups in a total of 50 mol or more in 1 t of the terminal-modified polyamide resin, it is possible to further suppress the decrease in the molecular weight retention rate during melt retention, further improve the thermal stability, and voids caused by the generated gas. Can be further reduced and the surface quality can be improved. The total content of these terminal groups is more preferably 60 mol / t or more, further preferably 80 mol / t or more. On the other hand, by containing an amino-terminal group and a carboxyl-terminal group in a total of 150 mol / t or less in the terminal-modified polyamide resin, the structure represented by the above general formula (I) is thermally decomposed in the terminal-modified polyamide resin during melt retention. And increase in molecular weight can be further suppressed, thermal stability can be further improved, voids can be further suppressed, and surface quality can be improved. The total content of these terminal groups is more preferably 135 mol / t or less, further preferably 120 mol / t or less.

Further, the terminal-modified polyamide resin of the present invention has a ratio of the content of amino-terminal groups [mol / t] to the content of carboxyl-terminal groups [mol / t] (content of amino-terminal groups / content of carboxyl-terminal groups). ) Is preferably 0.5 to 2.5 (0.5 or more and 2.5 or less). As described above, the larger the difference between the amount of amino-terminal groups and the amount of carboxyl-terminal groups, the more difficult it is for polymerization to proceed during melt retention, and the greater the decrease in molecular weight due to thermal decomposition. There is a tendency. Further, since the polymerization does not easily proceed during the melt retention and the terminal groups (amino terminal group and carboxyl terminal group) are not consumed in the polymerization reaction, these terminal groups serve as the thermal decomposition catalyst of the general formula (I) as described above, and are generally used. Since the thermal decomposition of the alkylene oxide structure in the terminal structure represented by the formula (I) is promoted, the melt viscosity tends to increase. By setting the molar ratio (content of amino terminal group / content of carboxyl terminal group) to 0.5 or more, the heat of the structure represented by the general formula (I) in the terminal-modified polyamide resin at the time of melt retention. Decomposition and increase in molecular weight can be further suppressed, thermal stability and impregnation property can be further improved, voids can be further reduced, and surface quality can be improved. The molar ratio (amino-terminal group / carboxyl-terminal group) is more preferably 0.6 or more, and even more preferably 0.8 or more. On the other hand, by setting the molar ratio (amino-terminal group / carboxyl-terminal group) to 2.5 or less, the thermal decomposition of the structure represented by the general formula (I) in the terminal-modified polyamide resin during melt retention is further suppressed. , Thermal stability can be further improved, voids in the substrate due to generated gas can be further reduced, and surface quality can be improved. The molar ratio (content of amino-terminal group / content of carboxyl-terminal group) is more preferably 2.4 or less, further preferably 2.3 or less.

Here, for the content of the amino-terminal group in the terminal-modified polyamide resin, the terminal-modified polyamide resin is dissolved in a phenol / ethanol mixed solution (ratio: 83.5 / 16.5 weight ratio), and thymol blue is used as an indicator. Then, it can be measured by titrating with an aqueous solution of hydrochloric acid. The content of the carboxyl terminal group in the terminal-modified polyamide resin is determined by dissolving the terminal-modified polyamide resin in benzyl alcohol at 195 ° C., using phenolphthalein as an indicator, and titrating with an ethanol solution of potassium hydroxide. Can be measured.

In the present invention, the ratio of the content of the amino terminal group to the content of the carboxyl terminal group of the terminal-modified polyamide resin is represented by, for example, the general formula (III) described later used in producing the terminal-modified polyamide resin. It can be adjusted to a desired range by adjusting the compounding ratio of the terminal modification compound and the terminal modification compound represented by the general formula (IV) and the reaction time.

The terminal-modified polyamide resin of the present invention has a relative viscosity (η _r ) of 1.3 to 3.0 (1.3 or more and 3.0 or less) at 25 ° C. of a 98% sulfuric acid solution having a resin concentration of 0.01 g / mL. It is preferably in the range. By setting η _r to 1.3 or more, the toughness can be improved and the mechanical properties of the base material can be improved. 1.4 or more is preferable, and 1.5 or more is more preferable. On the other hand, by setting η _r to 3.0 or less, the impregnation property can be further improved. 2.5 or less is preferable, and 2.1 or less is more preferable. 2.05 or less is more preferable, and 2.0 or less is most preferable.

In the present invention, the relative viscosity of the terminal-modified polyamide resin is represented by, for example, the terminal modification compound represented by the general formula (III) described later and the general formula (IV) used in producing the terminal-modified polyamide resin. It can be adjusted to a desired range by adjusting the blending amount of the terminal denaturing compound and the reaction time.

The weight average molecular weight (Mw) of the terminal-modified polyamide resin of the present invention measured by gel permeation chromatography (GPC) is preferably 15,000 or more. By setting Mw to 15,000 or more, the mechanical properties can be further improved. Mw is more preferably 18,000 or more, further preferably 20,000 or more. Further, Mw is preferably 50,000 or less. By setting Mw to 50,000 or less, the melt viscosity can be further reduced and the impregnation property can be further improved. Mw is more preferably 45,000 or less, further preferably 40,000 or less. For the weight average molecular weight (Mw) in the present invention, hexafluoroisopropanol (0.005N-sodium trifluoroacetate added) was used as a solvent, and "Shodex" (registered trademark) HFIP-806M (2 bottles) and HFIP were used as columns. -It is obtained by GPC measurement at 30 ° C. using LG. Polymethylmethacrylate is used as a molecular weight reference material.

In the present invention, the weight average molecular weight of the terminal-modified polyamide resin is represented by, for example, the terminal-modifying compound represented by the general formula (III) described later and the general formula (IV) used in producing the terminal-modified polyamide resin. It can be adjusted to a desired range by adjusting the blending amount of the terminal denaturing compound to be added and the reaction time.

The terminal-modified polyamide resin of the present invention preferably has a melt viscosity of 30 Pa · s or less under the conditions of a melting point of + 60 ° C. and a shear rate of 9,728 sec ^-1 . By setting the melt viscosity under the conditions of a melting point of + 60 ° C. and a shear rate of 9,728 sec ^-1 to 30 Pa · s or less, the impregnation property can be further improved. The melt viscosity is more preferably 20 Pa · s or less, further preferably 15 Pa · s or less, still more preferably 10 Pa · s or less. On the other hand, from the viewpoint of handleability, the melt viscosity is more preferably 0.1 Pa · s or more, further preferably 0.5 or more, and most preferably 1.0 or more.

The melt viscosity is determined by a capillary flow meter under the condition of a shear rate of 9,728 sec ^-1 after allowing the terminal-modified polyamide resin to stay for 5 minutes at a temperature of + 60 ° C. at the melting point of the terminal-modified polyamide resin. Can be measured. In the present invention, as an index for evaluating the melt viscosity, a melting point of + 60 ° C. is selected as a temperature condition in which the effect of good melt fluidization is likely to appear and thermal decomposition does not easily proceed with a short residence, and resin impregnation is performed. 9,728 sec ^-1 was selected as the shear rate, which is a high shear condition assuming the time.

In the present invention, the melt viscosity of the terminal-modified polyamide resin is represented by, for example, the terminal modification compound represented by the general formula (III) described later and the general formula (IV) used in producing the terminal-modified polyamide resin. It can be adjusted to a desired range by adjusting the blending amount of the terminal denaturing compound and the reaction time.

The terminal-modified polyamide resin of the present invention has a content retention rate of the terminal structure represented by the general formula (I) before and after residence at a melting point of + 60 ° C. for 60 minutes ((content after retention / content before retention) ×. It is preferable that 100) is 80% or more. By setting the content retention rate of the terminal structure represented by the general formula (I) to 80% or more, the terminal structure represented by the general formula (I) is thermally decomposed in the terminal-modified polyamide resin during melt retention. The amount of generated gas can be further reduced to further improve the thermal stability during melt retention, the voids caused by the generated gas can be further reduced, and the surface quality can be improved. The content retention rate of the terminal structure represented by the general formula (I) is more preferably 85% or more, further preferably 90% or more. Further, from the viewpoint of mechanical properties, the content retention rate of the terminal structure represented by the general formula (I) is preferably 100% or less.

For the content retention rate, the content of the terminal structure represented by the general formula (I) was determined for the terminal-modified polyamide resin by the above ^- mentioned 1H-NMR measurement, and then the terminal-modified in the capillary flow meter. After allowing the polyamide resin to stay at a melting point of + 60 ° C. for 60 minutes, the content of the terminal structure represented by the general formula (I) is similarly determined, and the terminal structure represented by the general formula (I) before melt retention is obtained. It can be calculated by dividing by the content of and multiplying by 100. In the present invention, as an index for evaluating the melt viscosity, a melting point of + 60 ° C. was selected as a temperature condition in which the effect of good melt fluidization is likely to appear and thermal decomposition does not easily proceed with a short residence.

In the present invention, the content retention rate of the terminal structure represented by the general formula (I) in the terminal-modified polyamide resin is represented by, for example, the general formula (III) described later used when producing the terminal-modified polyamide resin. The desired range can be adjusted by adjusting the blending amount of the terminal denaturing compound and the terminal denaturing compound represented by the general formula (IV) and the reaction time.

The terminal-modified polyamide resin of the present invention has a weight average molecular weight retention rate ((weight average molecular weight after retention / weight average molecular weight before retention) × 100) before and after residence for 60 minutes under the condition of melting point + 60 ° C. of 80 to 120% (80%). More than 120% or less) is preferable. By setting the weight average molecular weight retention rate to 80% or more, the mechanical properties can be further improved. The weight average molecular weight retention rate is more preferably 85% or more, further preferably 90% or more. On the other hand, by setting the weight molecular weight retention rate to 120% or less, the melt viscosity can be further reduced and the impregnation property can be further improved. The weight average molecular weight retention rate is more preferably 115% or less, still more preferably 110% or less.

The weight average molecular weight of the terminal-modified polyamide resin was measured by the above-mentioned gel permeation chromatography (GPC) for the weight molecular weight retention rate, and then in a capillary flow meter, the melting point of the terminal-modified polyamide resin was + 60 ° C. It can be calculated by measuring the weight average molecular weight in the same manner after allowing it to stay at a temperature for 60 minutes, dividing it by the weight average molecular weight before the melt retention, and multiplying by 100. In the present invention, as an index for evaluating the melt viscosity, a melting point of + 60 ° C. was selected as a temperature condition in which the effect of good melt fluidization is likely to appear and thermal decomposition does not easily proceed with a short residence.

In the present invention, the weight average molecular weight retention rate of the terminal-modified polyamide resin is, for example, the terminal modification compound represented by the general formula (III) described later and the general formula (IV) used in producing the terminal-modified polyamide resin. It can be adjusted to a desired range by adjusting the blending amount of the terminal modification compound represented by (1) and the reaction time.

The terminal-modified polyamide resin of the present invention has a melt viscosity retention rate ((melt viscosity after retention / melt viscosity before retention) x 100) before and after staying for 60 minutes under the condition of melting point + 60 ° C. of 80 to 120% (80% or more and 120%). The following) is preferable. By setting the melt viscosity retention rate to 80% or more, the impregnation property and mechanical properties can be further improved. The melt viscosity retention rate is more preferably 85% or more, further preferably 90% or more, still more preferably 95% or more. On the other hand, by setting the melt viscosity retention rate to 120% or less, the impregnation property can be further improved. The melt viscosity retention rate is more preferably 115% or less, still more preferably 110% or less.

The melt viscosity retention rate is determined by allowing the terminal-modified polyamide resin to stay at a temperature of + 60 ° C. for 5 minutes in order to melt the terminal-modified polyamide resin, and then allowing the capillary flow under the condition of a shear rate of 9,728 sec ^-1 . After the terminal-modified polyamide resin was allowed to stay for 60 minutes at the melt viscosity (melt viscosity before residence) measured by a meter and the melting point of the terminal-modified polyamide resin + 60 ° C., under the condition of a shear rate of 9,728 sec ^-1 . From the melt viscosity (melt viscosity after retention) measured by the capillary flow meter, it can be calculated by (melt viscosity after retention / melt viscosity before retention) × 100. In the present invention, as an index for evaluating the retention rate of melt viscosity, a melting point of + 60 ° C. is selected as a temperature condition in which the effect of good melt fluidization is likely to appear and thermal decomposition does not easily proceed with a short residence. 9,728 sec ^-1 was selected as the shear rate, which is a high shear condition assuming resin impregnation.

In the present invention, the melt viscosity retention rate of the terminal-modified polyamide resin is, for example, the terminal modification compound represented by the general formula (III) described later and the general formula (IV) used in producing the terminal-modified polyamide resin. It can be adjusted to a desired range by adjusting the blending amount of the represented terminal modification compound and the reaction time.

The terminal-modified polyamide resin of the present invention preferably has a weight loss rate of 4% or less before and after staying for 40 minutes under a nitrogen atmosphere and a melting point of + 60 ° C. By setting the weight reduction rate to 4% or less, it is possible to suppress voids in the fiber-reinforced end-modified polyamide resin caused by gas generated by thermal decomposition during processing, and it is possible to further improve the mechanical properties. At the same time, deterioration of surface quality due to deterioration of the resin can be suppressed. The weight loss rate is more preferably 3% or less, further preferably 2% or less.

This weight loss rate can be measured using a thermogravimetric analyzer (TGA). In the present invention, as an index for evaluating the weight loss rate, a melting point of + 60 ° C. was selected as a temperature condition in which the effect of good melt fluidization is likely to appear and thermal decomposition does not easily proceed with a short residence.

In the present invention, the weight reduction rate of the terminal-modified polyamide resin is represented by, for example, the terminal modification compound represented by the general formula (III) described later and the general formula (IV) used in producing the terminal-modified polyamide resin. It can be adjusted to a desired range by adjusting the blending amount of the terminal denaturing compound to be added and the reaction time.

Next, a method for producing the terminal-modified polyamide resin used in the embodiment of the present invention will be described.

As a method for producing the terminal-modified polyamide resin used in the embodiment of the present invention,
(1) A method in which a polyamide resin, a compound for terminal modification, and other components, if necessary, are melt-kneaded at a temperature equal to or higher than the melting point of the polyamide resin and reacted, or these are mixed in a solution and reacted, and then a solvent is used. A method of removing, and (2) a method of adding and reacting (2) a raw material constituting the main structural unit of the polyamide resin (main raw material of the polyamide resin), a compound for terminal modification, and other components as necessary (addition method at the time of reaction). ) And so on.

Hereinafter, the case where the terminal-modified polyamide resin of the embodiment of the present invention has the terminal structure represented by the general formula (I) and the terminal structure represented by the above (II) will be described as an example. As a method for producing such a terminal-modified polyamide resin, for example, a raw material for the polyamide resin, a terminal modification compound represented by the general formula (III), and a terminal modification compound represented by the following general formula (IV) can be used. Examples thereof include a method of reacting at the time of polymerization and a method of melt-kneading a polyamide resin and a compound for terminal modification. As a method of reacting at the time of polymerization, for example, a method of mixing a raw material of a polyamide resin and a compound for terminal modification in advance and then heating to proceed with condensation, or a method of adding a compound for terminal modification during the polymerization of a raw material as a main component. And the method of combining them.

The terminal-modified polyamide resin having the terminal structure represented by the general formula (I) can be polymerized by using the terminal modification compound represented by the following general formula (III). For example, when polymerizing amino acids, lactams, and / or diamines and dicarboxylic acids (in other words, using a combination of diamines and dicarboxylic acids, amino acids, and at least one selected from the group consisting of lactams as the main raw material. During polymerization), the terminal modification compound represented by the following general formula (III) is added in an amount of 1 to 20% by mass (1% by mass or more and 20% by mass) based on the total of amino acids, lactams, diamines and dicarboxylic acids (main raw materials). % Or less), and the terminal-modified polyamide resin containing 1 to 20% by mass of the terminal structure represented by the general formula (I) can be obtained by binding the terminal-modifying compound to the terminal of the polyamide resin. can.

HX- (R ¹ -O) _n -R ² (III)

In the above general formula (III), n represents a range of 2 to 100. Similar to m in the general formula (I), 5 or more is preferable, 8 or more is more preferable, and 16 or more is further preferable. On the other hand, n is preferably 70 or less, more preferably 50 or less. R ¹ represents a divalent hydrocarbon group having 2 to 10 carbon atoms, and R ² represents a monovalent hydrocarbon group having 1 to 30 carbon atoms. Examples are given as R ¹ and R ² in the general formula (I), respectively. X-indicates -NH-, -N (CH ₃ )-or -O (C = O)-. -NH-, which has excellent reactivity with the end of the polyamide, is more preferable.

The terminal-modified polyamide resin having the terminal structure represented by the general formula (II) can be polymerized by using the terminal modification compound represented by the following general formula (IV). For example, when polymerizing amino acids, lactams, and / or diamines and dicarboxylic acids (in other words, using a combination of diamines and dicarboxylic acids, amino acids, and at least one selected from the group consisting of lactams as the main raw material. During polymerization), the terminal modification compound represented by the following general formula (IV) is added to the total of amino acids, lactams, diamines and dicarboxylic acids (main raw materials) in an amount of 0.1 to 5% by mass (0.1% by mass). % Or more and 5% by mass or less), and by binding the terminal-modifying compound to the terminal of the polyamide resin, the terminal modification containing 0.1 to 5% by mass of the terminal structure represented by the general formula (II). Polyamide resin can be obtained.

HYR ³ (IV)

In the above general formula (IV), R ³ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms. Similar to the general formula (II) ^, a monovalent saturated hydrocarbon group is more preferable for R3 from the viewpoint of thermal stability and color prevention of the terminal-modified polyamide resin. When X in the general formula (III) is -NH- or -N (CH ₃ )-, -Y- in the general formula (IV) represents -O (C = O)-and the general formula (III). ) Is −O (C = O) −, then Y in the general formula (IV) represents −NH— or −N (CH ₃ ) −.

The number average molecular weight of the terminal modification compound represented by the general formula (III) is preferably 500 to 10,000. By setting the number average molecular weight to 500 or more, the melt viscosity can be further reduced and the impregnation property can be further improved. It is more preferably 800 or more, still more preferably 900 or more. On the other hand, by setting the number average molecular weight to 10,000 or less, the affinity of the polyamide resin with the main structural unit can be further improved, and the mechanical properties of the base material can be further improved. It is more preferably 5,000 or less, still more preferably 2,500 or less, still more preferably 1,500 or less.

Specific examples of the terminal modification compound represented by the general formula (III) include methoxypoly (ethylene glycol) amine, methoxypoly (trimethylethylene glycol) amine, methoxypoly (propylene glycol) amine, and methoxypoly (tetramethylene glycol) amine. , Methoxypoly (ethylene glycol) poly (propylene glycol) amine, methoxypoly (ethylene glycol) carboxylic acid, methoxypoly (trimethylethylene glycol) carboxylic acid, methoxypoly (propylene glycol) carboxylic acid, methoxypoly (tetramethylene glycol) carboxylic acid, methoxypoly (ethylene) Glycol) poly (propylene glycol) carboxylic acid and the like can be mentioned. When two kinds of polyalkylene glycols are contained, they may have a block polymerization structure or a random copolymerization structure. Two or more of the above-mentioned compounds for terminal modification may be used.

Specific examples of the terminal modification compound represented by the general formula (IV) include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, capric acid, pelargonic acid, undecanoic acid, lauric acid and tridecane. Alicyclic monocarboxylic acids such as acids, myristoic acid, myristoleic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, araquinic acid, cellotinic acid, cyclohexanecarboxylic acid, methylcyclohexanecarboxylic acid and the like. , Aromatic monocarboxylic acids such as benzoic acid, toluic acid, ethyl benzoic acid, phenylacetic acid, methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, heptylamine, octylamine, 2-ethylhexylamine, nonylamine, Alicyclic monoamines such as decylamines, undecylamines, dodecylamines, tridecylamines, tetradecylamines, pentadecylamines, hexadecylamines, octadecylamines, nonadesylamines, icosylamines, and alicyclic monoamines such as cyclohexylamines and methylcyclohexylamines. Examples include benzylamine and aromatic monoamines such as β-phenylethylamine. Two or more of the above-mentioned terminal modification compounds can also be used.

Next, for obtaining the terminal-modified polyamide resin having the terminal structure represented by the general formula (I) and the terminal structure represented by the general formula (II) of the present invention. An example of the method will be described. The methods (1) and (2) have been described above, but will be described in more detail below.

(1) When the terminal-modified polyamide resin is produced by melt-kneading the polyamide resin and the terminal-modifying compound, the melt-kneading temperature is 10 ° C. or higher and 40 ° C. or lower higher than the melting point (Tm) of the polyamide resin. It is preferable to react. For example, in the case of melt-kneading using an extruder, it is preferable that the cylinder temperature of the extruder is in the above range. By setting the melt-kneading temperature within this range, the terminal of the polyamide resin and the compound for terminal modification can be efficiently bonded while suppressing the volatilization of the compound for terminal modification and the decomposition of the polyamide resin. Examples of the polyamide resin include the above-mentioned polyamide resins.

(2) When a terminal-modified polyamide resin is produced by a method of reacting a raw material of a polyamide resin and a compound for terminal modification at the time of polymerization, a melt polymerization method in which the reaction is carried out at a temperature equal to or higher than the melting point of the polyamide resin and a reaction at a temperature lower than the melting point of the polyamide resin. Any solid-phase polymerization method may be used. Examples of the raw material for giving the polyamide resin include the above-mentioned amino acids, lactam and "mixture of diamine and dicarboxylic acid".

Specifically, it is preferable to charge the raw material of the terminal-modified polyamide resin into a reaction vessel, replace it with nitrogen, and heat it to react. If the reaction time at this time is too short, not only the molecular weight does not increase, but also the oligomer component increases, so that the mechanical properties may deteriorate. Therefore, the nitrogen flow time in the reaction time is preferably 15 minutes or more. On the other hand, if the reaction time is too long, thermal decomposition proceeds and coloring or the like occurs. Therefore, the nitrogen flow time in the reaction time is preferably 8 hours or less.

When a terminal-modified polyamide resin is produced by a method in which a raw material for a polyamide resin and a terminal-modifying compound are reacted at the time of polymerization, a polymerization accelerator can be added as needed. As the polymerization accelerator, for example, phosphoric acid, phosphoric acid, hypophosphoric acid, pyrophosphoric acid, polyphosphoric acid and inorganic phosphorus compounds such as alkali metal salts and alkaline earth metal salts thereof are preferable, and subphosphorus is particularly preferable. Sodium acid and sodium hypophosphite are preferably used. The polymerization accelerator is preferably used in the range of 0.001 to 1 part by mass with respect to 100 parts by mass of the raw material (excluding the compound for terminal modification) of the polyamide resin. By setting the addition amount of the polymerization accelerator to 0.001 to 1 part by mass, a terminal-modified polyamide resin having an excellent balance between mechanical properties and impregnation property can be obtained.

The fiber-reinforced polyamide resin base material of the present invention is obtained by impregnating the fiber-reinforced polyamide base material with the above-mentioned terminal-modified polyamide resin, and further contains a filler, other kinds of polymers, various additives and the like, if necessary. You may.

As the filler, any material generally used as a filler for resin can be used, and the strength, rigidity, heat resistance, and dimensional stability of the fiber-reinforced polyamide resin base material and the molded product can be further improved. Examples of the filler include glass fiber, carbon fiber, potassium titanate whisker, zinc oxide whisker, aluminum borate whisker, aramid fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, stone wool fiber, metal fiber and the like. Fibrous inorganic filler, wallastenite, zeolite, sericite, kaolin, mica, talc, clay, pyrophyllite, bentonite, montmorillonite, asbestos, aluminosilicate, alumina, silicon oxide, magnesium oxide, zirconium oxide, titanium oxide, oxidation Non-fibrous inorganic fillers such as iron, calcium carbonate, magnesium carbonate, dolomite, calcium sulfate, barium sulfate, magnesium hydroxide, calcium hydroxide, aluminum hydroxide, glass beads, ceramic beads, boron nitride, silicon carbide, silica, etc. Can be mentioned. Two or more of these may be contained. These fillers may be hollow. Further, it may be treated with a coupling agent such as an isocyanate-based compound, an organic silane-based compound, an organic titanate-based compound, an organic borane-based compound, and an epoxy compound. Further, as the montmorillonite, organic montmorillonite in which the interlayer ion is cation-exchanged with an organic ammonium salt may be used. In the fiber-reinforced polyamide resin base material according to the first aspect, if the fibrous filler is made of discontinuous fibers, it functions without impairing the reinforcing effect of the reinforcing fibers in the fiber-reinforced polyamide resin base material. Can be granted. On the other hand, in the fiber-reinforced polyamide resin base material in the second aspect, the fibrous filler can be used as long as the reinforcing effect of the discontinuous fiber base material is not impaired.

Examples of other polymers include polyolefins such as polyethylene and polypropylene, polyamide-based elastomers and elastomers such as polyester-based elastomers, polyesters, polycarbonates, polyphenylene ethers, polyphenylene sulfides, liquid crystal polymers, polysulfones, polyethersulfones, ABS resins, and SANs. Examples include resin and polystyrene. Two or more of these may be contained. In order to improve the impact resistance of the fiber-reinforced polyamide resin base material, the impact resistance of modified polyolefins such as (co) polymers of olefin-based compounds and / or conjugated diene-based compounds, polyamide-based elastomers, polyester-based elastomers, etc. An improver is preferably used.

Examples of the (co) polymer of the olefin compound and / or the conjugated diene compound include an ethylene polymer, a conjugated diene polymer, and a conjugated diene-aromatic vinyl hydrocarbon polymer.

Examples of the ethylene-based copolymer include a copolymer of ethylene and an α-olefin having 3 or more carbon atoms, a non-conjugated diene, vinyl acetate, vinyl alcohol, an α, β-unsaturated carboxylic acid and a derivative thereof. Can be mentioned. Examples of the α-olefin having 3 or more carbon atoms include propylene and butene-1. Examples of the non-conjugated diene include 5-methylidene-2-norbornene, 5-ethylidene-2-norbornene, dicyclopentadiene, 1,4-hexadiene and the like. Examples of the α, β-unsaturated carboxylic acid include acrylic acid, methacrylic acid, etacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, butendicarboxylic acid and the like. Examples of the derivative of the α, β-unsaturated carboxylic acid include an alkyl ester, an aryl ester, a glycidyl ester, an acid anhydride, and an imide of the α, β-unsaturated carboxylic acid.

The conjugated diene-based polymer refers to a polymer of at least one type of conjugated diene. Examples of the conjugated diene include 1,3-butadiene, isoprene (2-methyl-1,3-butadiene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene and the like. Further, a part or all of the unsaturated bonds of these polymers may be reduced by hydrogenation.

The conjugated diene-aromatic vinyl hydrocarbon-based copolymer refers to a copolymer of a conjugated diene and an aromatic vinyl hydrocarbon, and may be a block copolymer or a random copolymer. Examples of the conjugated diene include 1,3-butadiene, isoprene and the like. Examples of the aromatic vinyl hydrocarbon include styrene and the like. Further, a part or all of unsaturated bonds other than the double bond other than the aromatic ring of the conjugated diene-aromatic vinyl hydrocarbon-based copolymer may be reduced by hydrogenation.

Specific examples of the impact resistance improving agent include ethylene / methacrylic anhydride copolymers and a salt of some or all of the carboxylic acid moieties in these copolymers with sodium, lithium, potassium, zinc, and calcium. Examples thereof include ethylene / propylene-g-maleic anhydride copolymer and ethylene / butene-1-g-maleic anhydride copolymer.

Examples of various additives include antioxidants, heat-stabilizing agents (hindered phenol-based, hydroquinone-based, phosphite-based and their substitutes, copper halides, iodine compounds, etc.), and weather-resistant agents (resorcinol-based, salicylate-based). , Benzotriazole, benzophenone, hinderedamine, etc.), antistatic agents and lubricants (aliphatic alcohol, aliphatic amide, aliphatic bisamide, bisurea, polyethylene wax, etc.), pigments (cadmium sulfide, phthalocyanine, carbon black, etc.) , Dyes (niglocin, aniline black, etc.), plasticizers (octyl p-oxybenzoate, N-butylbenzene sulfonamide, etc.), antistatic agents (alkylsulfate-type anionic antistatic agents, quaternary ammonium salt-type cationic antistatic agents) Antistatic agents, non-ionic antistatic agents such as polyoxyethylene sorbitan monostearate, betaine-based antistatic agents, etc.), flame retardant agents (melamine cyanurate, hydroxides such as magnesium hydroxide, aluminum hydroxide, polyphosphoric acid) Ammonium, brominated polystyrene, brominated polyphenylene oxide, brominated polycarbonate, brominated epoxy resin, or a combination of these brominated flame retardants and trioxide antimon, etc.) and the like. Two or more of these may be blended.

The fiber-reinforced polyamide resin base material of the embodiment of the present invention can be obtained by impregnating continuous reinforcing fibers with a terminal-modified polyamide resin (first aspect). Alternatively, it can be obtained by impregnating a reinforcing fiber base material in which reinforcing fibers of discontinuous fibers are dispersed with a terminal-modified polyamide resin (second aspect).

As a method of impregnating the continuous reinforcing fibers with the terminal-modified polyamide resin in the first aspect, for example, a film-shaped terminal-modified polyamide resin is melted and pressed to impregnate the reinforcing fiber bundle with the terminal-modified polyamide resin. Film method, after blending fibrous end-modified polyamide resin and reinforcing fiber bundle, melt the fibrous end-modified polyamide resin and pressurize to impregnate the end-modified polyamide resin in the reinforcing fiber bundle, powder. After dispersing the terminal-modified polyamide resin in the form of a terminal-modified polyamide resin in the gaps between the fibers in the reinforced fiber bundle, the powder-like terminal-modified polyamide resin is melted and pressed to impregnate the reinforced fiber bundle with the terminal-modified polyamide resin. Examples thereof include a drawing method in which the reinforcing fiber bundle is dipped in the terminal-modified polyamide resin and the reinforcing fiber bundle is impregnated with the terminal-modified polyamide resin by applying pressure. The extraction method is preferable because it is possible to produce a variety of fiber-reinforced polyamide resin base materials having various thicknesses and fiber volume contents.

The thickness of the fiber-reinforced polyamide resin base material in the first aspect of the present invention is preferably 0.1 to 10 mm. When the thickness is 0.1 mm or more, the strength of the molded product obtained by using the fiber-reinforced polyamide resin base material can be improved. 0.2 mm or more is more preferable. On the other hand, when the thickness is 1.5 mm or less, it is easier to impregnate the reinforcing fibers with the terminal-modified polyamide resin. 1 mm or less is more preferable, 0.7 mm or less is further preferable, and 0.6 mm or less is further preferable.

For the volume content (V _f ) of the reinforcing fiber in the fiber-reinforced polyamide resin base material, after measuring the mass _W0 of the fiber-reinforced polyamide resin base material, the fiber-reinforced polyamide resin base material is heated in air at 500 ° C. for 30 minutes. Then, the polyamide resin component is burned off, the mass W1 of the _remaining reinforcing fiber is measured, and it can be calculated by the following formula.

V _f (volume%) = (W ₁ / ρ _f ) / {W ₁ / ρ _f + (W ₀ -W ₁ ) / ρ _r } × 100
ρ _f : Density of reinforcing fibers (g / cm ³ )
ρ _r : Density of terminal-modified polyamide resin (g / cm ³ )

Further, the fiber-reinforced polyamide resin base material according to the embodiment of the present invention can select a desired impregnation property according to its usage and purpose. For example, a prepreg having a higher impregnation property, a semi-impregnated semi-preg, a fabric having a low impregnation property, and the like can be mentioned. In general, a molding material having a higher impregnation property is preferable because a molded product having excellent mechanical properties can be obtained by molding in a short time.

As a method of impregnating the reinforcing fiber base material in which discontinuous fibers are dispersed in the second aspect of the present invention, for example, the terminal-modified polyamide resin is supplied by an extruder and impregnated into the reinforcing fiber base material. Method, method of dispersing and melting the powdered terminal-modified polyamide resin in the fiber layer of the reinforcing fiber base material, method of forming a film of the terminal-modified polyamide resin and laminating it with the reinforcing fiber base material, method of dissolving the terminal-modified polyamide resin in a solvent and dissolving it in a solution. A method of impregnating the reinforcing fiber base material in the above state and then volatilizing the solvent, a method of fiberizing the terminal-modified polyamide resin into a mixed yarn with discontinuous fibers, and using a precursor of the terminal-modified polyamide resin as the reinforcing fiber base material. Examples thereof include a method of impregnating the resin and then polymerizing the resin to form a terminal-modified polyamide resin, and a method of laminating using a melt blown non-woven fabric. Any method may be used, but the method of supplying the terminal-modified polyamide resin by an extruder and impregnating the reinforcing fiber base material has an advantage that it is not necessary to process the terminal-modified polyamide resin, and the powder is terminal-modified. The method of dispersing the polyamide resin in the fiber layer of the reinforcing fiber base material and melting it has an advantage that it is easy to impregnate, and the method of forming a terminal-modified polyamide resin into a film and laminating it with the reinforcing fiber base material has relatively good quality. It has the advantage of being able to obtain things.

The thickness of the fiber-reinforced polyamide resin base material in the second aspect of the present invention is preferably 0.1 to 10 mm. When the thickness is 0.1 mm or more, the strength of the molded product obtained by using the fiber-reinforced polyamide resin base material can be improved. 1 mm or more is more preferable. On the other hand, when the thickness is 10 mm or less, it is easier to impregnate the reinforcing fibers with the terminal-modified polyamide resin. 7 mm or less is more preferable, and 5 mm or less is further preferable.

Further, the fiber-reinforced polyamide resin base material according to the second aspect of the present invention can select a desired impregnation property according to its usage and purpose. In general, a molding material having a higher impregnation property is preferable because a molded product having excellent mechanical properties can be obtained by molding in a short time.

In producing the fiber-reinforced polyamide resin base material according to the second aspect of the present invention, as a method for adjusting the base material to a desired thickness and volume content, a method of heating and pressurizing using a press machine can be mentioned. The press is not particularly limited as long as it can achieve the temperature and pressure required for impregnation of the terminal-modified polyamide resin, and a normal press with a flat platen that moves up and down or a pair of endless steel belts can be used. A so-called double belt press machine having a traveling mechanism can be used.

The volume content of the fiber-reinforced polyamide resin base material of the present invention is preferably 10 to 70% by volume. In other words, it is preferable to contain 10 to 70% by volume (10% by volume or more and 70% by volume or less) of the reinforcing fibers with respect to the entire fiber-reinforced polyamide resin base material (100% by volume). By containing 10% by volume or more of the reinforcing fiber, the strength of the molded product obtained by using the fiber-reinforced polyamide resin base material can be further improved. 20% by volume or more is preferable, 30% by volume or more is more preferable, and 40% by volume or more is further preferable. On the other hand, by containing 70% by volume or less of the reinforcing fiber, it is easier to impregnate the reinforcing fiber with the terminal-modified polyamide resin. 60% by volume or less is more preferable, and 55% by volume or less is further preferable. The volume content can be adjusted to a desired range by adjusting the input amounts of the reinforcing fiber and the terminal-modified polyamide resin. Even when the base material is impregnated with the terminal-modified polyamide resin composition containing a filler such as carbon fiber, the volume content of the reinforcing fibers in the base material specified in the present invention is before the terminal-modified polyamide resin composition is impregnated. It refers to the volume content of the reinforcing fibers contained in the base material of.

In the present invention, the fiber-reinforced polyamide resin base material is obtained by laminating one or more fiber-reinforced polyamide resin base materials in the above-mentioned first and second embodiments with an arbitrary configuration, and then applying heat and / or pressure as necessary. It may be a base material obtained by molding while applying.

As a method of applying heat and / or pressure, for example, a press molding method in which a fiber-reinforced terminal-modified polyamide resin laminated in an arbitrary configuration is placed in a mold or on a press plate, and then the mold or press plate is closed and pressed. , Autoclave molding method in which the molded material laminated with an arbitrary configuration is put into an autoclave and pressurized and heated. Bagging molding method that heats in an oven, fiber-reinforced end-modified polyamide that is laminated in an arbitrary configuration, wrapping tape method that wraps tape while applying tension to a resin, and heats in an oven, fiber-reinforced end-modified polyamide that is laminated in an arbitrary configuration. Examples thereof include an internal pressure molding method in which a resin is placed in a mold and a gas or liquid is injected into a core also placed in the mold to pressurize the resin. In particular, since a molded product having few voids in the obtained molded product and having excellent appearance quality can be obtained, a molding method of pressing using a die is preferably used.

As a press molding method, a fiber-reinforced polyamide resin base material is placed in advance in a mold, pressure is applied and heated together with mold clamping, and then the fiber-reinforced polyamide resin base is cooled by cooling the mold while the mold is compacted. A hot press method in which the material is cooled to obtain a molded product, or a heating device such as a far-infrared heater, a heating plate, a high-temperature oven, or a dielectric heating device is used to heat the fiber-reinforced polyamide resin base material in advance to a temperature higher than the melting temperature of the terminal-modified polyamide resin. Then, in a state where the terminal-modified polyamide resin is melted and softened, it is placed on the mold which is the lower surface of the molding mold, then the mold is closed, the mold is fastened, and then stamping molding is performed. Can be adopted. The press molding method is not particularly limited, but stamping molding is desirable from the viewpoint of accelerating the molding cycle and increasing productivity.

[Polyamide resin molded product]
The present invention is a composite molded product in which the fiber-reinforced polyamide resin base material in the first and second forms and the polyamide resin molded product containing the polyamide resin are bonded at least in part.

The polyamide resin molded product bonded to the fiber-reinforced polyamide resin base material in the first and second embodiments of the present invention may contain a polyamide resin. By using a molded product containing a polyamide resin, the adhesive strength with the fiber-reinforced polyamide resin base material in the present invention is improved, and a composite molded product made of a polyamide resin having less mechanical properties and variations thereof can be obtained.

The polyamide resin composite molded product of the present invention has a fiber-reinforced polyamide resin substrate having a melting point of the impregnating polyamide resin (terminal-modified polyamide resin) impregnated in the fiber-reinforced polyamide resin substrate in the first and second embodiments. It is equal to or lower than the melting point of the polyamide resin in the polyamide resin molded product integrally molded with. When the melting point of the polyamide resin for impregnation is higher than the melting point of the polyamide resin in the polyamide resin composition, welding becomes insufficient at the interface between the base material and the molded product, and the mechanical properties of the polyamide resin composite molded product cannot be sufficiently obtained. Or, the variation in mechanical characteristics becomes large. Further, when the melting point of the polyamide resin for impregnation is 15 degrees or more lower than the melting point of the polyamide resin in the polyamide resin composition, the uniformity of the adhesive interface is further increased, the characteristics of the obtained polyamide resin composite molded product are enhanced, and the machine is used. This is preferable because the variation in characteristics is reduced. The melting point of the polyamide resin in the polyamide resin molded product can be measured by the same measuring method as the measuring method of the melting point of the terminal-modified polyamide resin. That is, the melting point of the polyamide resin in the polyamide resin molded product can be measured by cutting out a part of the molded product obtained by molding the polyamide resin composition and using differential scanning calorimetry (DSC).

For example, in the case of the terminal-modified polyamide resin, when the repeating structural unit constituting the main chain of the polymer is the structural unit constituting the main chain of the polyamide 6, the linear expansion coefficient is small as the polyamide resin molded product, and accordingly. Since the dimensional stability is high, the moldability is excellent, and the mechanical strength is high, it is preferable to include the polyamide 6 and the polyamide 66.

In general, a fiber-reinforced polyamide resin substrate containing fibers that are relatively long compared to the short fibers used in the injection molding material has a low coefficient of linear expansion. Therefore, the composite molded product obtained by joining the fiber-reinforced polyamide resin base material and the polyamide resin molded product may undergo dimensional changes such as warpage. Therefore, in order to improve the dimensional stability of the polyamide resin composite molded product, it is effective to reduce the difference in linear expansion coefficient between the polyamide resin molded product and the fiber-reinforced polyamide resin base material, and it is effective to reduce the difference in linear expansion coefficient between the polyamide resin molded product and the fiber-reinforced polyamide resin base material. However, it is preferable to contain at least a polyamide resin and a filler. As the filler, either an organic filler or an inorganic filler may be used, and either a fibrous filler or a non-fibrous filler may be used.

Examples of the fibrous filler include glass fibers, PAN (polyacrylonitrile) or pitch-based carbon fibers, stainless fibers, metal fibers such as aluminum fibers and brass fibers, organic fibers such as aromatic polyamide fibers, and gypsum fibers. Ceramic fiber, asbestos fiber, zirconia fiber, alumina fiber, silica fiber, titanium oxide fiber, silicon carbide fiber, rock wool, potassium titanate whisker, zinc oxide whisker, calcium carbonate whisker, wallastenite whisker, aluminum borate whisker, silicon nitride whisker Examples include fibrous or whisker-like fillers such as. As the fibrous filler, glass fiber is particularly preferable.

The type of glass fiber is not particularly limited as long as it is generally used for reinforcing the resin, and for example, it can be selected from long fiber type, short fiber type chopped strand, milled fiber and the like. Further, the glass fiber may be coated or bundled with a thermoplastic resin such as an ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin. Further, the cross section of the glass fiber is not limited to a circular shape, a flat gourd type, an eyebrows type, an oval shape, an elliptical shape, a rectangular shape, or similar products thereof. From the viewpoint of reducing the warp peculiar to the molded product, the cross section of the glass fiber is preferably a flat fiber having a major axis / minor axis ratio of 1.5 or more, more preferably 2 or more, and more preferably 10 or less. , 6 or less is more preferable. If the major axis / minor axis ratio is less than 1.5, the effect of flattening the cross section is small.

Examples of the non-fibrous filler include non-swellable silicates such as talc, warastenite, zeolite, sericite, mica, kaolin, clay, pyrophyllite, bentonite, asbestos, alumina silicate, and calcium silicate, and Li-type fluorine. Swellable layered silicate represented by teniolite, Na-type fluorine teniolite, Na-type tetrasilicon fluorine mica, and swellable mica of Li-type tetrasilicon fluorine mica, silicon oxide, magnesium oxide, alumina, silica, diatomaceous earth, zirconium oxide, oxidation. Metal oxides such as titanium, iron oxide, zinc oxide, calcium oxide, tin oxide, antimony oxide, metal carbonates such as calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, dolomite, hydrotalcite, calcium sulfate, barium sulfate Metal sulfates such as magnesium hydroxide, calcium hydroxide, aluminum hydroxide, metal hydroxides such as basic magnesium carbonate, smectite clay minerals such as montmorillonite, biderite, nontronite, saponite, hectrite, and soconite. Various clay minerals such as vermiculite, halloysite, kanemite, keniyaite, zirconium phosphate, titanium phosphate, glass beads, glass flakes, ceramic beads, boron nitride, aluminum nitride, silicon carbide, calcium phosphate, carbon black, graphite and the like can be mentioned. In the above-mentioned swellable layered silicate, exchangeable cations existing between layers may be exchanged with organic onium ions, and examples of the organic onium ions include ammonium ions, phosphonium ions, and sulfonium ions. Further, two or more kinds of these fillers may be contained.

The surface of the non-fibrous filler may be treated with a known coupling agent (for example, a silane-based coupling agent, a titanate-based coupling agent, etc.), and in this case, the machine of the molded product. The characteristics and surface appearance can be further improved. For example, a method in which the filler is surface-treated with a coupling agent in advance according to a conventional method and then melt-kneaded with the polyamide resin is preferably used. However, the filler and the polyamide resin are melt-kneaded without the surface treatment of the filler in advance. In the case of this, an integrable blending method in which a coupling agent is added may be used. The amount of the coupling agent to be treated is preferably 0.05 parts by weight or more, more preferably 0.5 parts by weight or more with respect to 100 parts by weight of the filler. On the other hand, the amount of the coupling agent to be treated is preferably 10 parts by weight or less, more preferably 3 parts by weight or less, based on 100 parts by weight of the filler.

The polyamide resin molded product according to the embodiment of the present invention preferably contains a polyamide resin and a filler, and in that case, the content of the filler is preferably 10 to 250 parts by weight with respect to 100 parts by weight of the polyamide resin. When the content of the filler is 10 parts by weight or more, the dimensional stability of the molded product can be further improved. The content of the filler is more preferably 20 parts by weight or more, further preferably 30 parts by weight or more. On the other hand, when the content of the filler is 250 parts by weight or less, the dimensional stability of the molded product is improved while maintaining the weldability. The content of the filler is more preferably 150 parts by weight or less, further preferably 100 parts by weight or less.

The polyamide resin molded product according to the embodiment of the present invention can contain a resin other than the polyamide resin and various additives depending on the purpose, as long as the effect of the present invention is not impaired. At this time, the preferable range of the amount of the filler is the ratio to the composition including the resin other than the polyamide resin and various additives.

Specific examples of resins other than polyamide resin include polyester resin, polyolefin resin, modified polyphenylene ether resin, polysulfone resin, polyketone resin, polyetherimide resin, polyarylate resin, polyether sulfone resin, polyether ketone resin, and polythioether. Examples thereof include a ketone resin, a polyether ether ketone resin, a polyimide resin, a polyamide imide resin, and a tetrafluoride polyethylene resin. When these resins are blended, the content thereof is preferably 30 parts by weight or less, and more preferably 20 parts by weight or less with respect to 100 parts by weight of the polyamide resin in order to fully utilize the characteristics of the polyamide resin.

Specific examples of various additives include heat stabilizers other than copper compounds, isocyanate compounds, organic silane compounds, organic titanate compounds, organic borane compounds, coupling agents such as epoxy compounds, and polyalkylene oxide oligomas. Plastics such as system compounds, thioether compounds, ester compounds, crystal nucleating agents such as polyether ether ketone, metal soaps such as montanic acid waxes, lithium stearate, aluminum stearate, ethylenediamine, stearic acid, sebacic acid weight Examples thereof include a condensate, a release agent such as a silicone-based compound, a lubricant, an ultraviolet inhibitor, a colorant, a flame retardant, an impact resistance improver, and a foaming agent. When these additives are contained, the content thereof is preferably 10 parts by weight or less, more preferably 1 part by weight or less, based on 100 parts by weight of the polyamide resin, in order to fully utilize the characteristics of the polyamide resin.

Examples of the heat stabilizer other than the copper compound include phenol-based compounds, sulfur-based compounds, amine-based compounds and the like. As the heat stabilizer other than the copper compound, two or more of these may be used.

As the phenolic compound, a hindered phenolic compound is preferably used, and N, N'-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamide), tetrakis [methylene-3- (3). ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] Methane and the like are preferably used.

Examples of the sulfur-based compound include an organic thioic acid-based compound, a mercaptobenzimidazole-based compound, a dithiocarbamic acid-based compound, and a thiourea-based compound. Among these sulfur-based compounds, mercaptobenzimidazole-based compounds and organic thioic acid-based compounds are preferable. In particular, a thioether-based compound having a thioether structure receives oxygen from an oxidized substance and reduces it, so that it can be suitably used as a heat stabilizer. Specific examples of the thioether compound include 2-mercaptobenzoimidazole, 2-mercaptomethylbenzoimidazole, ditetradecylthiodipropionate, dioctadecylthiodipropionate, and pentaerythritol tetrakis (3-dodecylthiopropionate). ), Pentaerythritol tetrakis (3-laurylthiopropionate) is preferable, and pentaerythritol tetrakis (3-dodecylthiopropionate) and pentaerythritol tetrakis (3-laurylthiopropionate) are more preferable. The molecular weight of the sulfur-based compound is usually 200 or more, preferably 500 or more, and the upper limit thereof is usually 3,000.

As the amine-based compound, a compound having a diphenylamine skeleton, a compound having a phenylnaphthylamine skeleton and a compound having a dinaphthylamine skeleton are preferable, and a compound having a diphenylamine skeleton and a compound having a phenylnaphthylamine skeleton are further preferable. Among these amine compounds, 4,4'-bis (α, α-dimethylbenzyl) diphenylamine, N, N'-di-2-naphthyl-p-phenylenediamine and N, N'-diphenyl-p-phenylenediamine are included. More preferably, N, N'-di-2-naphthyl-p-phenylenediamine and 4,4'-bis (α, α-dimethylbenzyl) diphenylamine are particularly preferable.

As the combination of the sulfur-based compound or the amine-based compound, a combination of pentaerythritol tetrakis (3-laurylthiopropionate) and 4,4'-bis (α, α-dimethylbenzyl) diphenylamine is more preferable.

The method for producing a polyamide resin molded product according to the embodiment of the present invention will be described below. As the polyamide resin molded product, a molded product obtained by molding pellets containing a polyamide resin using a known molding method can be used. The method for producing pellets containing a polyamide resin is not particularly limited, but production in a molten state, production in a solution state, or the like can be used, and production in a molten state can be preferably used from the viewpoint of improving reactivity. For production in the molten state, melt-kneading by an extruder, melt-kneading by a kneader, or the like can be used, but from the viewpoint of productivity, melt-kneading by an extruder capable of continuously producing is preferable. For melt kneading with an extruder, one or more extruders such as a single-screw extruder, a twin-screw extruder, a multi-screw extruder such as a four-screw extruder, and a twin-screw single-screw compound extruder can be used, but kneading property is possible. From the viewpoint of improving reactivity and productivity, a multi-screw extruder such as a twin-screw extruder or a four-screw extruder is preferable, and a method by melt-kneading using a twin-screw extruder is most preferable.

The polyamide resin molded product according to the embodiment of the present invention can be obtained by molding pellets containing the polyamide resin produced by the above method by any molding method. Examples of the molding method include injection molding, injection compression molding, extrusion molding, compression molding, blow molding, press molding and the like. Injection molding is preferable from the viewpoint of productivity and easy molding of a molded product having a complicated shape. The shape of the resin molded product includes, for example, a sheet, a film, a fiber, and the like, and is not particularly limited.

As described above, the composite molded product of the present invention may be a method in which a fiber-reinforced polyamide resin base material and a polyamide resin molded product are separately manufactured and partially bonded to each other. It is also possible to integrally mold a reinforced polyamide resin base material and a polyamide resin molded product to obtain a composite molded product.

The composite molded product of the embodiment of the present invention has a fiber-reinforced polyamide resin base material and a polyamide resin molded product, and can be obtained by joining at least a part of the fiber-reinforced polyamide resin base material and the polyamide resin molded product. .. Examples of the method for partially joining the fiber-reinforced polyamide resin base material and the polyamide resin molded product include various welding methods such as laser welding, vibration welding, ultrasonic welding, and injection welding, and bonding with an adhesive. .. Among them, injection welding is particularly preferable. More specifically, in injection welding, a fiber-reinforced polyamide resin base material impregnated with an impregnating polyamide resin is placed in a mold in advance, and the polyamide resin (or polyamide resin composition) is injected into the mold. This is a method of joining a fiber-reinforced polyamide resin base material and a polyamide resin molded product in the process of molding, melting the polyamide resin (or polyamide resin composition) by heat, and then resolidifying, and the productivity of the composite molded product. Can be improved.

The polyamide resin composite molded product according to the embodiment of the present invention is used for various purposes such as aircraft parts, automobile parts, electric / electronic parts, building parts, various containers, daily necessities, household goods and sanitary goods by utilizing its excellent characteristics. can do. The polyamide resin composite molded product according to the embodiment of the present invention is, among other things, aircraft parts, automobile body parts, automobile underhood parts, automobile gear parts, automobile interior parts, which are required to have weldability, rigidity and dimensional stability. It is particularly preferably used for automobile exterior parts, automobile electrical parts, and electric / electronic parts. Specifically, the polyamide resin composite molded product according to the embodiment of the present invention includes aircraft-related parts such as landing gear pods, winglets, spoilers, edges, ladders, elevators, failing, ribs, front bodies, under bodies, and the like. Various pillars, various members, various frames, various beams, various supports, various rails, various hinges and other automobile body parts, cooling fans, radiator tank tops and bases, cylinder head covers, oil pans, brake pipes, fuel pipe tubes, Automotive underhood components such as waste gas system components, automotive gear components such as gears, actuators, bearing retainers, bearing cages, chain guides, chain tensioners, shift lever brackets, steering lock brackets, key cylinders, door inner handles, door handle cowls. , Interior mirror bracket, air conditioner switch, instrument panel, console box, glove box, steering wheel, trim and other automobile interior parts, front fender, rear fender, fuel lid, door panel, cylinder head cover, door mirror stay, tailgate panel, license garnish , Roof rails, engine mount brackets, rear garnishes, rear spoilers, trunk lids, rocker moldings, moldings, lamp housings, front grilles, mudguards, side bumpers and other automobile exterior parts, connectors and wire harness connectors, motor parts, lamp sockets, sensors Automotive electrical components such as in-vehicle switches and combination switches, as well as electrical and electronic components, include, for example, generators, motors, transformers, current transformers, voltage regulators, rectifiers, resistors, inverters, relays, power contacts, open / close. Vessels, breakers, switches, knife switches, other pole rods, motor cases, TV housings, laptop housings and internal parts, CRT display housings and internal parts, printer housings and internal parts, mobile phones, mobile PCs, handheld mobiles, etc. Mobile terminal housing and internal parts, IC and LED compatible housing, condenser seat plate, fuse holder, various gears, various cases, cabinets and other electrical parts, connectors, SMT compatible connectors, card connectors, jacks, coils, coil bobbins, Speakers, LED lamps, sockets, resistors, relays, relay cases, reflectors, small switches, power supply parts, coil bobbins, capacitors, variable condenser cases, optical pickup chassis, oscillators, various terminal boards, transformers, plugs, printed boards, tuners. , Speakers, microphones, headphones, small motors, magnetic head bases, power modules, Si power modules and SiC power modules, semiconductors, liquid crystal, FDD carriages, FDD chassis, motor brush holders, transformer members, parabolic antennas, computer-related parts, etc. It is preferably used for electronic parts and the like.

Examples are shown below, and the present invention will be described in more detail, but the present invention is not limited to the description of these examples. The characteristic evaluation in each Example and Comparative Example was performed according to the following method.

[Volume content (V _f )] "
After measuring the mass W0 of the fiber-reinforced polyamide resin base material obtained in each Example and Comparative Example, the fiber-reinforced polyamide resin base material was heated in air at 500 ° C. for 30 minutes to burn off the polyamide resin component and remain. The mass W1 of the reinforcing fiber was measured, and the volume content (V _f ) of the fiber-reinforced polyamide resin base material was calculated by the following formula (VI).

V _f (volume%) = (W ₁ / ρ _f ) / {W ₁ / ρ _f + (W ₀ -W ₁ ) / ρ _r } × 100
ρ _f : Density of reinforcing fibers (g / cm ³ )
ρ _r : Density of terminal-modified polyamide resin (g / cm ³ )

[Relative viscosity (η _r )]
The relative viscosities of the terminal-modified polyamide resin or the polyamide resin obtained in each Example and Comparative Example were measured at 25 ° C. using an Ostwald viscometer with respect to a 98% sulfuric acid solution having a resin concentration of 0.01 g / mL.

[Molecular weight]
The terminal-modified polyamide resin or the polyamide resin 2.5 mg obtained in each Example and Comparative Example was dissolved in 4 ml of hexafluoroisopropanol (with 0.005N-sodium trifluoroacetate), and the obtained solution was 0.45 μm. Filtered with a filter. Using the obtained solution, the number average molecular weight (Mn) and the weight average molecular weight (Mw) (weight average molecular weight before melt retention) were measured by GPC measurement. The measurement conditions are shown below.

Pump: e-Alliance GPC system (manufactured by Waters)
Detector: Differential Refractometer Waters 2414 (manufactured by Waters)
Column: Shodex HFIP-806M (2) + HFIP-LG
Solvent: Hexafluoroisopropanol (with 0.005N-sodium trifluoroacetate added)
Flow velocity: 1 mL / min
Sample injection volume: 0.1 mL
Temperature: 30 ° C
Molecular weight standard substance: polymethylmethacrylate.

[Amino-terminal group amount [NH ₂ ]]
Weigh accurately 0.5 g of the terminal-modified polyamide resin or polyamide resin obtained in each Example and Comparative Example, add 25 mL of a phenol / ethanol mixed solution (ratio: 83.5 / 16.5 mass ratio), and dissolve at room temperature. Then, using thymol blue as an indicator, the mixture was titrated with 0.02 specified hydrochloric acid to determine the amount of amino terminal groups (mol / t).

[Carboxylic acid terminal group amount [COOH]]
0.5 g of the terminal-modified polyamide resin or polyamide resin obtained in each Example and Comparative Example was precisely weighed, 20 mL of benzyl alcohol was added and dissolved at a temperature of 195 ° C., and then 0.02 using phenolphthalein as an indicator. Using the specified ethanol solution of potassium hydroxide, titration was performed at 195 ° C. to determine the amount of carboxyl terminal groups (mol / t).

[Identification of terminal structure and quantification of content of terminal structure of general formula (I) and content of terminal structure of general formula (II)]
With respect to the terminal-modified polyamide resin or the polyamide resin obtained in Examples and Comparative Examples, ¹ H-NMR measurement was carried out using FT-NMR: JNM-AL400 manufactured by JEOL Ltd. First, a solution having a sample concentration of 50 mg / mL was prepared using sulfuric acid deuterated as a measurement solvent. ¹ H-NMR measurement of the polyamide resin was carried out at 256 times of integration. The peak derived from R ¹ and R ² in the terminal structure represented by the general formula (I), the peak derived from the R ³ portion in the terminal structure represented by the general formula (II), and the repeating structural unit of the polyamide resin skeleton. The peak was identified. The integrated intensity of each peak is calculated, and from the calculated integrated intensity and the number of hydrogen atoms in each structural unit, the content of the terminal structure represented by the general formula (I) in the terminal-modified polyamide resin [I] ( The mol / t, mass%) (content before retention) and the content [II] (mol / t, mass%) of the terminal structure represented by the general formula (II) were calculated, respectively.

[Melting point]
Using a differential scanning calorimeter (DSC Q20) manufactured by TA Instruments, weigh 5 to 7 mg of the terminal-modified polyamide resin or polyamide resin obtained in each Example and Comparative Example, and raise the temperature from 20 ° C. in a nitrogen atmosphere. The temperature was raised to 250 ° C. at a temperature rate of 20 ° C./min. The apex of the endothermic peak that appears when the temperature is raised is defined as Tm (melting point).

[Melting viscosity]
The terminal-modified polyamide resin or polyamide resin obtained in each Example and Comparative Example was dried in a vacuum dryer at 80 ° C. for 12 hours or more. Using a capillary flow meter (Capillograph 1C type manufactured by Toyo Seiki Seisakusho Co., Ltd.) as a measuring device for melt viscosity, a melting point of + 60 ° C. and a shear rate of 9,728 sec- at an orifice with a diameter of 0.5 mm ^and a length of 5 mm. The melt viscosity (melt viscosity before retention) was measured under the condition of ¹ . However, in order to melt the terminal-modified polyamide resin or the polyamide resin, the measurement was carried out after allowing the resin to stay for 5 minutes. The smaller the value of the melt viscosity, the higher the fluidity.

[Melting viscosity retention rate]
The terminal-modified polyamide resin or polyamide resin obtained in each Example and Comparative Example was dried in a vacuum dryer at 80 ° C. for 12 hours or more. Using a capillary flow meter (Capillograph 1C type manufactured by Toyo Seiki Seisakusho Co., Ltd.), melt and stay for 60 minutes at a melting point of + 60 ° C. at an orifice with a diameter of 0.5 mm and a length of 5 mm, and then a shear rate of 9,728 sec ^-1 . The melt viscosity (melt viscosity after retention) was measured under the conditions of. From the melt viscosity (melt viscosity before retention) and melt viscosity (melt viscosity after retention) measured by the above method, the melt viscosity retention rate [%] was calculated by (melt viscosity after retention / melt viscosity before retention) × 100.

[Weight average molecular weight retention rate]
The terminal-modified polyamide resin or polyamide resin obtained in each Example and Comparative Example was dried in a vacuum dryer at 80 ° C. for 12 hours or more. Using a capillary flow meter (Capillary Graph 1C type, manufactured by Toyo Seiki Seisakusho Co., Ltd.), melt retention was performed for 60 minutes at a melting point of + 60 ° C. at an orifice having a diameter of 0.5 mm and a length of 5 mm. With respect to the terminal-modified polyamide resin or the polyamide resin after melt retention, the weight average molecular weight (Mw) (weight average molecular weight after retention) was measured by the same GPC measurement as the above-mentioned molecular weight measuring method. From the weight average molecular weight (weight average molecular weight before melting and retention) and weight average molecular weight (weight average molecular weight after retention) measured by the above method, the weight average molecular weight is maintained by (weight average molecular weight after retention / weight average molecular weight before retention) × 100. The rate [%] was calculated.

[Content retention rate]
The terminal-modified polyamide resin or polyamide resin obtained in each Example and Comparative Example was dried in a vacuum dryer at 80 ° C. for 12 hours or more. Using a capillary flow meter (Capillary Graph 1C type, manufactured by Toyo Seiki Seisakusho Co., Ltd.), melt retention was performed for 60 minutes at a melting point of + 60 ° C. at an orifice having a diameter of 0.5 mm and a length of 5 mm. For the terminal-modified polyamide resin or polyamide resin after melt retention, the content of the terminal structure represented by the general formula (I) in the terminal-modified polyamide resin by ¹ H-NMR measurement in the same manner as the above-mentioned terminal structure content measurement method [ I] (mol / t) (content after retention) was calculated. The content of the terminal structure represented by the general formula (I) [I] (mol / t) (content before retention) measured by the above method and the content of the terminal structure represented by the general formula (I) [ I] From (mol / t) (content after retention), the content retention rate was calculated by (content after retention / content before retention) × 100.

[Weight loss rate]
The terminal-modified polyamide resin or polyamide resin obtained in each Example and Comparative Example was dried in a vacuum dryer at 80 ° C. for 12 hours or more. Cut out 20 mg of an arbitrary portion, and use a thermogravimetric analyzer (TGA7, manufactured by PerkinElmer) to hold the terminal-modified polyamide resin or polyamide resin at the melting point of + 60 ° C for 40 minutes in a nitrogen gas atmosphere to reduce the weight before and after heat treatment. The rate [%] was measured.

[Tension breaking elongation]
The terminal-modified polyamide resin or polyamide resin obtained in each Example and Comparative Example was dried in a vacuum dryer at 80 ° C. for 12 hours or more. Using an IS55EPN injection molding machine manufactured by Toshiba Machinery Co., Ltd., the cylinder temperature is set to the melting point (Tm) + 60 ° C of the terminal-modified polyamide resin or polyamide resin, the mold temperature is set to 80 ° C, and the injection time and the holding pressure time are combined. Under the molding cycle conditions of 10 seconds and a cooling time of 10 seconds, an evaluation test piece of an ASTM No. 4 dumbbell having a test piece thickness of 1/25 inch (about 1.0 mm) was injection-molded. The obtained ASTM No. 4 dumbbell type test piece was subjected to "Tencilon" (registered trademark) UTA-2.5T (manufactured by Orientec), and according to ASTM-D638, in an atmosphere of 23 ° C. and 50% humidity. A tensile test was performed at a strain rate of 10 mm / min, and the tensile elongation at break was measured.

[Immersion and thermal stability]
The cross section in the thickness direction of the fiber-reinforced polyamide resin base material obtained in each Example and Comparative Example was observed as follows. A sample in which the fiber-reinforced terminal-modified polyamide resin was embedded in an epoxy resin was prepared, and the sample was polished until the cross section of the fiber-reinforced terminal-modified polyamide resin in the thickness direction could be observed well. The polished sample was photographed at a magnification of 400 times using an ultra-depth color 3D shape measuring microscope VHX-9500 (controller unit) / VHZ-100R (measurement unit) (manufactured by KEYENCE CORPORATION). The imaging range was the range of the thickness of the fiber-reinforced terminal-modified polyamide resin × the width of 500 μm. In the photographed image, the area of the part occupied by the resin and the area of the part having voids were obtained, and the impregnation rate was calculated by the following formula.

Impregnation rate (%) = 100 x (total area of the part occupied by the resin) / {(total area of the part occupied by the resin) + (total area of the part that is a void)}

The impregnation property and thermal stability of the fiber-reinforced polyamide resin substrate are determined by the fact that voids are reduced when the impregnation property and thermal stability are high, and voids are increased when at least one of the impregnation property or thermal stability is low. Using this impregnation rate as a criterion, evaluation was made in the following two stages, and good was regarded as acceptable. The fiber-reinforced polyamide resin base material in the first aspect was produced at a processing temperature of a melting point of + 30 ° C. The fiber-reinforced polyamide resin base material in the second aspect was produced at a processing temperature of melting point + 30 ° C.
Good: The impregnation rate is 98% or more.
Defective: Impregnation rate is less than 98%.

[Surface quality]
The surface quality of the fiber-reinforced terminal-modified polyamide resin or the fiber-reinforced polyamide resin substrate obtained in each Example and Comparative Example was visually observed. The surface quality was evaluated in the following two stages, and good was accepted.
Good: Surface scratches, discoloration of matrix resin, no exposure of reinforcing fibers Defective: Surface scratches, discoloration of matrix resin, exposure of reinforcing fibers

The fiber-reinforced polyamide resin base material in the first aspect was produced at a processing temperature of melting point + 30 ° C. The fiber-reinforced polyamide resin base material in the second aspect was produced at a processing temperature of melting point + 30 ° C.

[material]
In Examples and Comparative Examples, the raw materials shown below were used.
-Carbon fiber bundle: T700S-12K manufactured by Toray Industries, Inc.
-Glass fiber: T-275H manufactured by Nippon Electric Glass Co., Ltd.
・ Ε-Caprolactam: Wako Pure Chemical Industries, Ltd., Wako special grade.
-Hexamethylenediamine: Wako Pure Chemical Industries, Ltd., Wako First Class.
-Adipic acid: Wako Pure Chemical Industries, Ltd., Wako special grade.
-Sebacic acid: Wako Pure Chemical Industries, Ltd., Wako first grade.

[Compound for terminal modification represented by the general formula (III)]
Methoxypoly (ethylene glycol) poly (propylene glycol) amine represented by the following structural formula (chemical formula 1): "JEFFAMINE" (registered trademark) M1000 (number average molecular weight Mn1,000) manufactured by HUNTSMAN.

Methoxypoly (ethylene glycol) poly (propylene glycol) amine represented by the following structural formula (chemical formula 2): "JEFFAMIN" (registered trademark) M2070 (number average molecular weight Mn2,000) manufactured by HUNTSMAN.

[Compound for terminal modification represented by the general formula (IV)]
-Benzoic acid: Made by Wako Pure Chemical Industries, Ltd., special grade reagent.

[Polyamide resin composition (for polyamide resin molded products)]
The polyamide resin shown in each of the following examples is supplied from the first supply port of the Werner-Pfleidere twin-screw extruder ZSK57, and the content of glass fiber as a filler is as shown in the table from the second supply port. The mixture was melt-kneaded at a melting point of + 25 ° C., a discharge rate of 60 kg / hr, and a screw rotation speed of 200 rpm to obtain pellets of a polyamide resin composition.

[Bending strength]
The composite molded product made of polyamide resin was cut into 50 mm × 10 mm with the reinforced fiber axial direction of the fiber reinforced polyamide resin base material as the long side, and 10 bending test pieces were produced. This test piece was subjected to a bending test at a crosshead speed of 2 mm / min using a "Instron" (registered trademark) universal testing machine type 5566 (manufactured by Instron) in accordance with JIS K7171-2008. The average value of 10 measurements was taken as the bending strength, and the difference between the maximum value and the minimum value (absolute value) was taken as the variation.

[Example 1]
20 g of ε-caprolactam, 20 g of ion-exchanged water, 1.6 g of "JEFFAMIN" M1000, and 0.14 g of benzoic acid were placed in a reaction vessel, sealed, and replaced with nitrogen. The set temperature of the heater on the outer periphery of the reaction vessel was set to 290 ° C., and heating was started. After the pressure inside the can reached 1.0 MPa, the pressure inside the can was maintained at 1.0 MPa while releasing water to the outside of the system, and the temperature was raised until the temperature inside the can reached 240 ° C. After the temperature inside the can reached 240 ° C, the set temperature of the heater was changed to 270 ° C, and the pressure inside the can was adjusted so that the pressure became normal over 1 hour (the temperature inside the can when the normal pressure was reached: 243 ° C). .. Subsequently, the can was held for 240 minutes while flowing nitrogen (nitrogen flow) to obtain a terminal-modified polyamide 6 resin (maximum temperature reached: 253 ° C.). Subsequently, the obtained terminal-modified polyamide 6 resin was subjected to Soxhlet extraction with ion-exchanged water to remove unreacted terminal-modifying compounds. The terminal-modified polyamide 6 resin thus obtained had a relative viscosity of 1.81, a weight average molecular weight of 30,000, a melting point (Tm) of 220 ° C., and a melt viscosity of 5.5 Pa · s. Further, the obtained terminal-modified polyamide 6 resin contained a terminal-modified polyamide 6 resin having a structure represented by the following chemical formula 3 and a structure represented by the following chemical formula 4 at the ends. Other physical characteristics are shown in the table.

Sixteen bobbins wrapped with carbon fiber bundles were prepared, and carbon fiber bundles were continuously sent out from each bobbin through a thread guide. The continuously delivered carbon fiber bundle was impregnated with the terminal-modified polyamide 6 resin obtained by the above-mentioned method, which was quantitatively supplied from the filled feeder in the impregnated die. The carbon fibers impregnated with the terminal-modified polyamide 6 resin in the impregnated die were continuously drawn from the nozzle of the impregnated die at a pulling speed of 1 m / min using a take-up roll. The temperature at which carbon fiber is pulled out is called the processing temperature. The extracted carbon fiber bundle passed through a cooling roll to cool and solidify the terminal-modified polyamide 6 resin, and was taken up by a winder as a continuous fiber-reinforced polyamide resin base material. The obtained fiber-reinforced polyamide resin base material had a thickness of 0.3 mm and a width of 50 mm, and was arranged in one direction in the reinforcing fiber direction to obtain a fiber-reinforced polyamide resin base material having a volume content of 50% by volume. .. The obtained fiber-reinforced polyamide resin base material was subjected to the above evaluation. The evaluation results are shown in the table.

As the polyamide resin for the polyamide resin molded product, Amylan (registered trademark) CM1011G-30 manufactured by Toray Co., Ltd. was used, and a polyamide resin composition was obtained according to the above-mentioned [Polyamide resin composition (for polyamide resin molded product)].

Using the fiber-reinforced polyamide resin base material obtained above and the polyamide resin composition, a polyamide resin composite molded product was obtained by the following method. In the obtained composite molded product made of polyamide resin, the fiber-reinforced polyamide resin base material and the polyamide resin molded product were partially bonded. The obtained physical properties are shown in the table.

[Polyamide resin composite molded product]
The polyamide resin composition was vacuum-dried at 80 ° C. for 12 hours, and used with an injection molding machine (J1000EL III-3900H manufactured by Japan Steel Works, Ltd.) under the conditions of a cylinder temperature of 300 ° C. and a mold temperature of 120 ° C. The fiber-reinforced polyamide resin base material shown in the table, which was cut to an appropriate size, was placed on both sides of a flat plate mold with a length of 500 mm, a width of 50 mm, and a thickness of 3 mm. A polyamide composite molded product having a sandwich structure having a base material was obtained. The fiber-reinforced polyamide resin base material was arranged so that the axial direction of the reinforced fiber was substantially parallel to the longitudinal direction of the composite molded product made of polyamide resin.

[Example 2]
A polyamide resin composite molded product was obtained in the same manner as in Example 1 except that the terminal-modified polyamide 6 resin obtained in Example 1 was used as the polyamide resin composition. The obtained physical properties are shown in the table.

[Example 3]
A polyamide resin composite molded product was obtained in the same manner as in Example 1 except that "Amilan" (registered trademark) CM3006G-30 manufactured by Toray Industries, Inc. was used as the polyamide resin composition. The obtained physical properties are shown in the table.

[Example 4]
A polyamide resin composite molded product was obtained in the same manner as in Example 1 except that "Amilan" (registered trademark) CM2006 manufactured by Toray Industries, Inc. was used as the polyamide resin composition. The obtained physical properties are shown in the table.

[Example 5]
Example 1 except that the raw material was changed to the composition shown in the table, the pressure inside the can was set to normal pressure, and then the time for holding the can while flowing nitrogen (nitrogen flow time) was changed to the time shown in the table. In the same manner as above, a terminal-modified polyamide 6 resin was obtained. The obtained terminal-modified polyamide 6 resin contained a terminal-modified polyamide 6 resin having a structure represented by the following chemical formula 5 and a structure represented by the above chemical formula 4 at the ends.

A composite molded product made of a polyamide resin was obtained in the same manner as in Example 1 except that the terminal-modified polyamide 6 resin obtained above was used instead of the terminal-modified polyamide 6 resin obtained in Example 1. The obtained physical properties are shown in the table.

[Example 6]
9.46 g of hexamethylenediamine, 11.92 g of adipic acid, 20 g of ion-exchanged water, 1.6 g of "JEFFAMIN" (registered trademark) M1000 and 0.14 g of benzoic acid were placed in a reaction vessel, sealed, and replaced with nitrogen. The set temperature of the heater on the outer periphery of the reaction vessel was set to 290 ° C., and heating was started. After the pressure inside the can reached 1.75 MPa, the pressure inside the can was maintained at 1.75 MPa while releasing water to the outside of the system, and the temperature was raised until the temperature inside the can reached 260 ° C. After the temperature inside the can reached 260 ° C, the set temperature of the heater was changed to 290 ° C, and the pressure inside the can was adjusted so that the pressure became normal over 1 hour (the temperature inside the can when the normal pressure was reached: 270 ° C). .. Subsequently, the can was held for 240 minutes while flowing nitrogen (nitrogen flow) to obtain a terminal-modified polyamide 66 resin (maximum temperature reached: 275 ° C.). Here, the obtained polyamide resin contained the terminal-modified polyamide 66 resin having the structure shown in Example 1 at the end.

A fiber-reinforced polyamide 66 resin base material was obtained using the obtained terminal-modified polyamide 66 resin in the same manner as in Example 1 except that the processing temperature was set to 320 ° C. The physical characteristics of the obtained terminal-modified polyamide 66 resin and the physical properties of the fiber-reinforced polyamide 66 resin base material are shown in the table.

A polyamide resin composite molded product was obtained in the same manner as in Example 3 except that the fiber-reinforced polyamide resin base material obtained above was used. The obtained physical properties are shown in the table.

[Example 7]
Hexamethylenediamine (7.74 g), sebacic acid (13.46 g), ion-exchanged water (20 g), "JEFFAMIN" (registered trademark) M1000 (1.6 g) and benzoic acid (0.14 g) were placed in a reaction vessel, sealed, and replaced with nitrogen. The set temperature of the heater on the outer periphery of the reaction vessel was set to 290 ° C., and heating was started. After the pressure inside the can reached 1.0 MPa, the pressure inside the can was maintained at 1.0 MPa while releasing water to the outside of the system, and the temperature was raised until the temperature inside the can reached 240 ° C. After the temperature inside the can reached 240 ° C, the set temperature of the heater was changed to 290 ° C, and the pressure inside the can was adjusted so that the pressure became normal over 1 hour (the temperature inside the can when the normal pressure was reached: 243 ° C). .. Subsequently, the can was held for 240 minutes while flowing nitrogen (nitrogen flow) to obtain a terminal-modified polyamide 610 resin (maximum temperature reached: 253 ° C.). Here, the obtained polyamide resin contained the terminal-modified polyamide 610 resin having the structure shown in Example 1 below at the end.

A fiber-reinforced polyamide 610 resin base material was obtained using the obtained terminal-modified polyamide 610 resin in the same manner as in Example 1 except that the processing temperature was set to 280 ° C. The physical characteristics of the obtained terminal-modified polyamide 610 resin and the physical properties of the fiber-reinforced polyamide 610 resin base material are shown in the table.

A polyamide resin composite molded product was obtained in the same manner as in Example 4 except that the fiber-reinforced polyamide resin base material obtained above was used. The obtained physical properties are shown in the table.

[Example 8]
A composite molded product made of a polyamide resin was obtained in the same manner as in Example 1 except that the blending amount in the polyamide resin composition was changed. The obtained physical properties are shown in the table.

[Example 9]
Example 1 except that the raw material was changed to the composition shown in the table, the pressure inside the can was set to normal pressure, and then the time for holding the can while flowing nitrogen (nitrogen flow time) was changed to the time shown in the table. In the same manner as above, a terminal-modified polyamide 6 resin was obtained.

[Comparative Example 1]
Example 1 except that the raw material was changed to the composition shown in the table, the pressure inside the can was set to normal pressure, and then the time for holding the can while flowing nitrogen (nitrogen flow time) was changed to the time shown in the table. The polyamide 6 resin was obtained in the same manner as above. A fiber-reinforced polyamide resin base material was obtained in the same manner as in Example 1 except that the obtained polyamide 6 resin was used instead of the terminal-modified polyamide 6 resin obtained in Example 1. The physical properties of the obtained terminal-modified polyamide 6 resin and the physical properties of the fiber-reinforced polyamide resin base material are shown in the table.

[Comparative Example 2]
A polyamide resin composite molded product was obtained in the same manner as in Comparative Example 1 except that Toray's "Amilan" CM3006G-30 was used as the polyamide resin composition. The obtained physical properties are shown in the table.

Claims (11)

A composite molded product obtained by bonding a fiber-reinforced polyamide resin base material obtained by impregnating a reinforcing fiber base material with a polyamide resin for impregnation and a polyamide resin molded product containing the polyamide resin at least in part.
The terminal-modified polyamide resin in which the impregnating polyamide resin has a structure in which at least a part of the polymer constituting the polyamide resin is composed of structural units different from the repeating structural units constituting the main chain of the polymer at the terminal group of the polymer. And
The melting point of the polyamide resin for impregnation is equal to or lower than the melting point of the polyamide resin in the polyamide resin molded product, and the terminal-modified polyamide resin contains 1 to 20% by mass of the terminal structure represented by the following general formula (I). Polyamide resin composite molded product characterized by
-X- (R ¹ - O) _m - R ² (I)
In the above general formula (I), m represents a range of 2 to 100. R ¹ represents a divalent hydrocarbon group having 2 to 10 carbon atoms, and R ² represents a monovalent hydrocarbon group having 1 to 30 carbon atoms. -X- represents -NH-, -N (CH ₃ )-or-(C = O)-. The m R1s included in the general formula (I) ^may be the same or different. The composite molded product made of a polyamide resin according to claim 1 , wherein the terminal-modified polyamide resin further contains a terminal structure represented by the following general formula (II) in an amount of 0.1 to 5% by mass.
-YR ³ (II)
In the above general formula (II), R ³ represents a monovalent hydrocarbon group having 1 to 30 carbon atoms. When X in the general formula (I) is -NH- or -N (CH ₃ )-, -Y- in the general formula (II) represents-(C = O)-, and the general formula (I) When X in-(C = O)-, Y in the above general formula (II) represents -NH- or -N (CH ₃ )-. The composite molded product made of a polyamide resin according to claim 1 or 2 , wherein the melting point of the terminal-modified polyamide resin is 15 degrees or more lower than the melting point of the polyamide resin in the polyamide resin molded product. The polyamide resin according to any one of claims 1 to 3 , wherein the polyamide resin molded product contains at least a polyamide resin and a filler, and the content thereof is 10 to 250 parts by weight of the filler with respect to 100 parts by weight of the polyamide resin. Made of composite molded product. The composite molded product made of a polyamide resin according to any one of claims 1 to 4 , which comprises continuous reinforcing fibers in which the reinforcing fiber base materials are arranged in one direction. The composite molded product made of a polyamide resin according to claim 5 , wherein the reinforcing fibers are carbon fibers and the fiber content in the fiber-reinforced polyamide resin base material is 10 to 70% by volume. A fiber-reinforced polyamide resin base material in which a reinforcing fiber base material is impregnated with an impregnating polyamide resin is placed in a mold in advance, and a polyamide resin composition is injection-molded into the mold to be melt-bonded. The terminal modification of the polymer, wherein at least a part of the polymer constituting the impregnating polyamide resin has a structure composed of structural units different from the repeating structural units constituting the main chain of the polymer at the terminal group of the polymer. It is a polyamide resin, and the melting point of the impregnating polyamide resin is lower than the melting point of the polyamide resin in the polyamide resin composition, and the terminal-modified polyamide resin has a terminal structure represented by the following general formula (I) of 1 to 20. A method for manufacturing a composite molded product made of polyamide resin , which contains% by mass .
-X- (R ¹ - O) _m - R ² (I)
In the above general formula (I), m represents a range of 2 to 100. R ¹ represents a divalent hydrocarbon group having 2 to 10 carbon atoms, and R ² represents a monovalent hydrocarbon group having 1 to 30 carbon atoms. -X- represents -NH-, -N (CH ₃ )-or-(C = O)-. The m R1s included in the general formula (I) ^may be the same or different. The method for producing a composite molded product made of a polyamide resin according to claim 7 , wherein the polyamide resin composition contains 10 to 250 parts by weight of a filler with respect to 100 parts by weight of the polyamide resin. The method for producing a composite molded product made of a polyamide resin according to claim 7 or 8 , wherein the melting point of the terminal-modified polyamide resin is 15 degrees or more lower than the melting point of the polyamide resin in the polyamide resin composition. The method for producing a composite molded product made of a polyamide resin according to any one of claims 7 to 9 , wherein the reinforcing fiber base material is composed of continuous reinforcing fibers arranged in one direction. The method for producing a polyamide resin composite molded product according to claim 10 , wherein the reinforcing fibers are carbon fibers and the fiber content in the fiber-reinforced polyamide resin base material is 10 to 70% by volume.