JP4726474B2 - Manufacturing method of polyamide composite injection molded article - Google Patents

Description

  The present invention relates to a method for injection molding a polyamide composite material containing a swellable layered silicate.

  A polyamide resin composition in which a silicate layer of a swellable layered silicate is dispersed in a polyamide resin at a molecular level is excellent in heat resistance and dimensional stability with low specific gravity, high strength, and high elastic modulus (Patent Document 1). Already used for various purposes. However, the conventional polyamide resin composition containing the swellable layered silicate has insufficient impact resistance, and various attempts to improve impact resistance have been proposed.

  For example, according to a mixture (see Patent Document 2) with an impact resistance improving material made of an olefinic copolymer, the impact resistance of the polyamide resin composition can be greatly improved. In addition, the matrix resin has a high molecular weight during the production of the polyamide resin composition (see Patent Document 3), or the cation exchange capacity and initial particle diameter of the swellable layered silicate are optimized (see Patent Document 4). There is an impact improvement method. In addition to impact resistance, there is also a method of adding a fibrous reinforcing material or an inorganic filler to a polyamide resin composition for the purpose of further improving strength and elastic modulus (Patent Document 5). It has also been found that a further advanced polyamide composite material can be obtained by combining the good moldability and material properties of the polyamide resin with the characteristics of other polymers. For example, Patent Document 6 proposes a polyamide composite material composed of a polyamide resin composition composed of a swellable layered silicate and a polyamide resin and a polyphenylene ether-based resin. Such a composite material has moldability and heat resistance. The balance of impact resistance is excellent.

However, a general method for producing these polyamide composite materials is that a polyamide resin composition comprising a swellable layered silicate and a polyamide resin and a second component (polymer, reinforcing material and various kinds of materials for the purpose of improving the performance thereof). Improvement material) is melt-kneaded using an extruder. However, the provision of such a melt-kneading step makes the manufacturing process complicated and causes an increase in production cost.
Patent No. 2941159 Japanese Patent No. 2528163 JP 11-172100 A WO98 / 49235 Japanese Patent No. 2528163 Japanese Patent No. 21407779 JP-A-8-302062

  An object of the present invention is to provide a molded article made of a polyamide resin composition in which a silicate layer of a swellable layered silicate is dispersed at a molecular level without undergoing a step of melt-kneading using an extruder in advance. The object of the present invention is to provide a molded article made of a polyamide resin composition excellent in mechanical properties such as elastic modulus and excellent in toughness, durability, frictional wear resistance and low water absorption by injection molding.

  As a result of diligent research to solve the above-mentioned problems, the present inventor has obtained a polyamide resin composition (A) in which a silicate layer of a swellable layered silicate is dispersed in a polyamide resin at a molecular level and a polyamide resin ( By subjecting B) to a specific blending ratio and injection molding using a mixture in which the volume ratio of each pellet of the polyamide resin composition (A) and the polyamide resin (B) is within a specific range, the present invention The present inventors have found that the above problem can be solved, and have reached the present invention.

  That is, the gist of the present invention is as follows.

95-50 parts by mass of a polyamide resin composition (A) pellet in which a silicate layer of a swellable layered silicate is dispersed in a polyamide resin at a molecular level, and 5-50 parts by mass of a polyamide resin (B) pellet In the method for producing an injection-molded article of a polyamide composite material (C) made of a mixture, the pellets of the polyamide resin (B) constituting the polyamide composite material (C) are pellets 1 with respect to the pellets of the polyamide resin composition (A). A method for producing a polyamide composite material injection-molded product , wherein the volume ratio per grain is in the range of 0.2 to 0.9.

  According to the present invention, mechanical properties such as strength and elastic modulus are excellent without passing through a melt-kneading step using an extruder in advance, and also excellent in toughness, durability, friction wear resistance, and low water absorption. Moreover, the molded article which consists of a polyamide resin composition by which the silicate layer of a swelling layered silicate is disperse | distributed at a molecular level can be provided at low cost.

  Hereinafter, the present invention will be described in detail.

  The polyamide resin composition (A) in the present invention is a polyamide resin matrix in which a silicate layer of a swellable layered silicate is dispersed at a molecular level. Here, the silicate layer is a basic unit constituting the swellable layered silicate, and is a plate-like inorganic crystal obtained by breaking the layer structure of the swellable layered silicate (hereinafter referred to as “cleavage”). . In the present invention, the silicate layers dispersed in the polyamide resin matrix do not necessarily have to be separated one by one. In addition, when dispersed in the polyamide resin matrix, the swellable layered silicate silicate layer has an average distance of 1 nm or more, and does not form a lump with each other. The state that is. Here, the lump refers to a state where the swellable layered silicate as a raw material is not cleaved. The interlayer distance is the distance of the silicate layer. The dispersion state of the silicate layer in the polyamide resin matrix can be confirmed by, for example, observation with a transmission electron microscope.

  The swellable layered silicate used in the present invention has a structure composed of a negatively charged crystal layer mainly composed of silicate and a cation having an ion exchange ability interposed between the layers, and will be described later. It is desirable that the cation exchange capacity determined in (1) is 50 meq / 100 g or more. When the cation exchange capacity is less than 50 meq / 100 g, the swelling ability is low, so that the polyamide composite material remains substantially in an uncleaved state, and an improvement in the performance of the resulting polyamide composite material is recognized. Absent. In the present invention, the upper limit of the value of the cation exchange capacity is not particularly limited, and an appropriate one may be selected from swellable layered silicates that can be actually prepared.

  The swellable layered silicate may be naturally occurring, artificially synthesized or modified, for example, smectite group (montmorillonite, beidellite, hectorite, soconite, etc.), vermiculite group (vermiculite, etc.), mica group (Fluorine mica, muscovite, paragonite, phlogopite, lepidrite, etc.), brittle mica family (margarite, clintonite, anandite, etc.), chlorite family (donbasite, sudite, kukeite, clinochlore, chamonite, nimite, etc.) In the present invention, Na-type or Li-type swellable fluorinated mica and montmorillonite are particularly preferably used.

  The swellable fluorine mica preferably used in the present invention generally has a structural formula represented by the following formula.

M ((Mg _x Li () Si ₄ O _y F _z
(In the formula, M represents an ion-exchangeable cation, and specific examples include sodium and lithium. Further, (, (, X, Y, and Z represent coefficients, respectively, and 0 ≦ (≦ 0.5, 0 ≦ (≦ 0.5, 2.5 ≦ X ≦ 3, 10 ≦ Y ≦ 11, 1.0 ≦ Z ≦ 2.0)
As a method for producing such a swellable fluorine mica, for example, silicon oxide, magnesium oxide and various fluorides are mixed, and the mixture is completely melted in a temperature range of 1400 to 1500 ° C. in an electric furnace or a gas furnace. A melting method in which a crystal of swellable fluorinated mica grows in the reaction vessel during the cooling process.

On the other hand, there is also a method of using talc [Mg ₃ Si ₄ O ₁₀ (OH) ₂ ] as a starting material and intercalating alkali metal ions to impart swellability to obtain a swellable fluorinated mica (Japanese Patent Laid-Open No. Hei. No. 2-149415). In this method, swellable fluoromica can be obtained by heat-treating talc and alkali silicofluoride mixed at a predetermined blending ratio in a magnetic crucible at a temperature of 700 to 1200 ° C. for a short time.

  At this time, the amount of alkali silicofluoride mixed with talc is preferably in the range of 10 to 35% by mass of the entire mixture. If it is out of this range, the yield of swellable fluorinated mica tends to decrease.

  The montmorillonite used in the present invention is represented by the following formula, and can be obtained by refining a naturally produced product using a water syrup treatment or the like.

_{M a Si (Al 2-a} Mg) O 10 (OH) 2 · nH 2 O
(In the formula, M represents a cation such as sodium, and 0.25 ≦ a ≦ 0.6. The number of water molecules bound to the ion-exchangeable cation between layers varies depending on conditions such as cation species and humidity. Therefore, it is expressed in nH ₂ O in the formula)
In addition, montmorillonite is known to have isomorphic ion substitution products such as magnesia montmorillonite, iron montmorillonite, iron magnesia montmorillonite, and these may be used.

  In the present invention, there is no particular limitation on the initial particle size of the swellable layered silicate. Here, the initial particle size is the particle size of the swellable layered silicate as a raw material used in the production of the (A) polyamide resin composition used in the present invention, and is different from the size of the silicate layer in the composite material. It is. However, this particle size also has a considerable influence on the physical properties of the obtained polyamide composite material, in particular the rigidity and heat resistance. Therefore, it is desirable to take this point into consideration when selecting the mixing ratio of the above-mentioned swellable layered silicate, and it is preferable to control the particle size by pulverizing with a jet mill or the like as necessary.

  Here, when the swellable fluoromica mineral is synthesized by the intercalation method, the initial particle size can be changed by appropriately selecting the particle size of talc as a raw material. This is a preferable method in that the initial particle diameter can be adjusted in a wider range by using in combination with pulverization.

  The polyamide resin matrix of the polyamide resin composition (A) in the present invention and the polyamide in the polyamide resin (B) are mainly raw materials of aminocarboxylic acid, lactam or diamine and dicarboxylic acid (including a pair of salts thereof). A polymer having an amide bond in the main chain. Specific examples of the raw material include aminocarboxylic acid such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, paraaminomethylbenzoic acid and the like. Examples of the lactam include ε-caprolactam, ω-undecanolactam, and ω-laurolactam. Examples of diamines include tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4- / 2,4,4-trimethylhexamethylenediamine, 5-methylnonamethylenediamine, 2,4- Dimethyloctamethylenediamine, metaxylylenediamine, paraxylylenediamine, 1,3-bis (aminomethyl) cyclohexane, bis (4-aminocyclohexyl) methane, bis (3-methyl-4-aminocyclohexyl) methane, 2, There are 2-bis (4-aminocyclohexyl) propane, bis (aminopropyl) piperazine, aminoethylpiperazine and the like. Examples of dicarboxylic acids include adipic acid, speric acid, azelaic acid, sebacic acid, dodecanedioic acid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium sulfo Examples include isophthalic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid. These diamines and dicarboxylic acids can also be used as a pair of salts.

  Preferred examples of the polyamide resin include polycaproamide (nylon 6), polytetramethylene adipamide (nylon 46), polyhexamethylene adipamide (nylon 66), polycaproamide / polyhexamethylene adipamide copolymer ( Nylon 6/66), polyundecamide (nylon 11), polycaproamide / polyundecamide copolymer (nylon 6/11), polydodecamide (nylon 12), polycaproamide / polydodecamide copolymer (nylon 6/12), poly Hexamethylene sebacamide (nylon 610), polyhexamethylene dodecamide (nylon 612), polyundecamethylene adipamide (nylon 116), polyhexamethylene isophthalamide (nylon 6I), polyhexamethylene terephthalamide (nylon) T), polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), polycaproamide / polyhexamethylene terephthalamide copolymer (nylon 6 / 6T), polycaproamide / polyhexamethylene isophthalamide copolymer ( Nylon 6 / 6I), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (nylon 66 / 6T), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6I), polytrimethylhexamethylene Terephthalamide (nylon TMDT), polybis (4-aminocyclohexyl) methane dodecamide (nylon PACM12), polybis (3-methyl-4-aminocyclohexyl) methane dodecamide (Nai Njimechiru PACM12), poly-m-xylylene terephthalamide (nylon MXD6), polyundecamethylene terephthalamide (nylon 11T), and mixtures thereof or copolymers thereof. Of these, nylon 6 and nylon 66 are particularly preferable.

  The method for producing the polyamide resin composition (A) of the present invention basically uses an initiator such as water after charging a predetermined amount of monomer in an autoclave in the presence of an appropriately selected swellable layered silicate. The melt polycondensation method may be performed within the range of a temperature of 240 to 300 ° C., a pressure of 0.2 to 3 MPa, and a time of 1 to 15 hours. When nylon 6 is used as the resin matrix, it is preferable to polymerize at a temperature of 250 to 280 ° C., a pressure of 0.5 to 2 MPa, and a range of 3 to 5 hours.

  In order to remove the polyamide monomer remaining in the polyamide resin composition after polymerization, it is preferable to scour the pellets of the polyamide resin composition with hot water. In this case, the treatment is preferably performed in hot water at 90 to 100 ° C. for 8 hours or more.

  At this time, the compounding amount of the swellable layered silicate is preferably 0.5 to 20% by mass and more preferably 0.5 to 10% by mass with respect to the monomer forming the polyamide resin. When the blending amount is less than 0.5% by mass, the reinforcing effect of the polyamide resin matrix by the silicate layer of the swellable layered silicate is poor. On the other hand, when the blending amount of the swellable layered silicate exceeds 20% by mass, it is difficult to dispense the polyamide composite material produced from the autoclave, which is not preferable because the yield is greatly reduced.

  It is also desirable to provide a step of mixing the swellable layered silicate and a part of the polyamide monomer required for the polymerization of the polyamide resin in a dispersion medium such as water, methanol, ethanol, ethylene glycol or the like. In general, the temperature condition in this step is preferably room temperature or, if necessary, room temperature or higher and below the boiling point of the dispersion medium, and it is desirable to use a homomixer, an ultrasonic dispersing machine, a high-pressure dispersing machine, or the like.

  In producing the polyamide resin composition (A), an acid may be added. The addition of an acid is preferable because cleavage of the swellable layered silicate is promoted and the dispersion of the silicate layer in the polyamide resin matrix further proceeds.

  As the acid, if pKa (25 ° C., value in water) is 0-6 or a negative acid, it may be an organic acid or an inorganic acid. Specifically, benzoic acid, sebacic acid, formic acid, acetic acid, chloroacetic acid, Examples include trichloroacetic acid, trifluoroacetic acid, nitrous acid, phosphoric acid, phosphorous acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, nitric acid, sulfuric acid, perchloric acid and the like.

  The amount of acid added is about 1.0 to 5.0 moles relative to the total cation exchange capacity of the swellable layered silicate used, and the cleavage of the swellable layered silicate and the polymerization in the polyamide resin matrix It is preferable from the point of action as a catalyst.

  The polyamide resin (B) used in the present invention may be a conventional melt polymerization method regardless of batch type or continuous type. The production method is as follows. After a predetermined amount of monomer is charged into an autoclave, an initiator such as water is used, and melt polycondensation is performed within a temperature range of 240 to 300 ° C., a pressure of 0.2 to 3 MPa, and a pressure range of 1 to 15 hours. Good. When nylon 6 is used as the resin matrix, it is preferable to polymerize at a temperature of 250 to 280 ° C., a pressure of 0.5 to 2 MPa, and a range of 3 to 5 hours.

  In order to remove the polyamide monomer remaining in the polyamide resin after polymerization, it is preferable to scour the polyamide resin pellets with hot water. In this case, hot water at 90 to 100 ° C. The process for 8 hours or more may be performed.

  In the present invention, the polyamide resin composition (A) and the polyamide resin (B) are mixed with each other. That is, in the present invention, the polyamide composite material (C) composed of the polyamide resin composition (A) and the polyamide resin (B) is melt-kneaded in a plasticizing process at the time of injection molding, and extruded in advance. The step of melt-kneading using a machine is omitted.

In the present invention, it is necessary that the polyamide resin (B) pellets have a volume ratio per pellet of 0.2 to 0.9 as compared with the polyamide resin composition (A) pellets. Desirably, it is preferably in the range of 0.3 to 0.7. By setting it as such a pellet volume ratio, the uniform dispersibility of the silicate layer in the molded article which consists of a polyamide composite material obtained can be improved. When the volume ratio is less than 0.2, the polyamide resin (B) pellets are too small. For example, they are separated from the polyamide resin composition (A) pellets in a hopper of an injection molding machine, and the uniform dispersibility is obtained. descend. On the other hand, even if the volume ratio exceeds 0.9, the uniform dispersibility decreases.

  In the present invention, it is necessary to mix 95 to 50 parts by mass of the polyamide resin composition (A) pellets and 5 to 50 parts by mass of the polyamide resin (B) pellets.

  When the ratio of the polyamide resin composition (A) exceeds 95 parts by mass, the effect of modification by the polyamide resin (B) becomes poor, and when the ratio of the polyamide resin (B) exceeds 50 parts by mass, rigidity, heat resistance, etc. descend. A more desirable mixing ratio is 90 to 60 parts by mass of the polyamide resin composition (A) pellets and 10 to 40 parts by mass of the polyamide resin (B) pellets.

  The polyamide resin (B) in the present invention can be blended with a fibrous reinforcing material, a particulate reinforcing material, a plate-like reinforcing material, and the like as necessary.

  Examples of such reinforcing materials include clay, talc, calcium carbonate, zinc carbonate, wollastonite, silica, alumina, magnesium oxide, calcium silicate, sodium aluminate, sodium aluminosilicate, magnesium silicate, glass balloon, carbon black, Zeolite, hydrotalcite, metal fiber, metal whisker, ceramic whisker, potassium titanate whisker, boron nitride, graphite, glass fiber, carbon fiber and the like can be mentioned.

  In addition, the polyamide resin (B) in the present invention includes a heat stabilizer, an antioxidant, a reinforcing material, a pigment, an anti-coloring agent, a weathering agent, a flame retardant, a plasticizer, a crystal nucleating agent, and a release agent as necessary. Etc. may be added.

  In the present invention, the polyamide resin composition (A) and the polyamide resin (B) pellets may be mixed by injection molding using a tumbler or the like according to a predetermined ratio. Absent.

  Furthermore, other thermoplastic resins may be mixed in the polyamide composite material in the present invention. Examples of the thermoplastic resin include polybutadiene, butadiene / styrene copolymer, acrylic rubber, ethylene / propylene copolymer, ethylene / propylene / diene copolymer, natural rubber, chlorinated butyl rubber, elastomer such as chlorinated polyethylene, and the like. Modified with maleic anhydride, styrene / maleic anhydride copolymer, styrene / phenylmaleimide copolymer, polyethylene, polypropylene, butadiene / acrylonitrile copolymer, polyvinyl chloride, polyethylene terephthalate, polyacetal, polyvinylidene fluoride, Polysulfone, polyphenylene sulfide, polyether sulfone, phenoxy resin, polyphenylene ether, polymethyl methacrylate, polyether ketone, polycarbonate, polytetrafluoroethylene Ren, polyarylate and the like can be mentioned. These resins are desirably mixed with the polyamide resin (B) in advance.

    Next, the present invention will be described more specifically with reference to examples.

In addition, the measurement method of the material used in the Example and a physical property test is as follows.
1. Material (1) Polyamide resin composition (P-1)
To talc pulverized so as to have an average particle size of 4.0 μm by a ball mill, sodium silicofluoride having an average particle size of 10 μm was mixed so as to be 15% by mass of the total amount. This was put in a magnetic crucible and reacted at 850 ° C. for 1 hour in an electric furnace to obtain a swellable fluorine mica having an average particle size of 4.0 μm. The composition of this swellable fluorine mica was Na _0.60 Mg _2.63 Si ₄ O ₁₀ F _1.77 , and the cation exchange capacity obtained by the measurement method described later was 110 meq / 100 g.

  Add 400 g of this swellable fluorinated mica (total cation exchange capacity is equivalent to 0.44 mol), 1 kg of ε-caprolactam and 1 kg of water, and add it at room temperature using a homomixer. Stir for 1.5 hours. The total amount of this swellable fluorinated mica dispersion was previously charged in 9 kg of ε-caprolactam and 50.7 g (0.44 mol) of 85 mass% phosphoric acid aqueous solution, and these were melted at 95 ° C., 30 liters in internal volume Was added to an autoclave, heated to 260 ° C. with stirring, and the pressure was increased to 0.7 MPa. Thereafter, while gradually releasing water vapor, the temperature of 260 ° C. and the pressure of 0.7 MPa were maintained for 1 hour, and the pressure was released to normal pressure over 1 hour, followed by polymerization for 30 minutes in a nitrogen stream.

  When the polymerization was completed, the reaction product was discharged into a strand, cooled and solidified, and then cut to obtain a pellet made of the polyamide resin composition (P-1). Next, the pellets were refined with hot water at 95 ° C. for 8 hours and then dried.

Content of the silicate layer in P-1 by ash measurement was 4.2 mass%. Moreover, as a result of the pellet size measurement mentioned later, the average dimension was 2.4 mm in diameter and 1.9 mm in length (height).
(2) Polyamide resin (P-2)
“A1030BRT” manufactured by Unitika Ltd. was used. In order to change the pellet size, pellets having three types of sizes were obtained using a small twin screw extruder (PCM30 type, manufactured by Ikekai Tekko Co., Ltd.) under a barrel temperature condition of 250 ° C. The average dimensions of the obtained pellets are 1.5 mm in diameter and 1.8 mm in length (hereinafter referred to as “small-diameter pellet”), 2.4 mm in diameter and 1.9 mm in length (hereinafter “standard”). Pellets)) and a diameter of 2.8 mm and a length of 3.4 mm (hereinafter “large-diameter pellet”).
2. Measurement Method (1) Cation Exchange Capacity The cation exchange capacity was determined based on the bentonite (powder) cation exchange capacity measurement method (JBAS-106-77) according to the standard test method of the Japan Bentonite Industry Association.

That is, using a device in which a leachate container, a leach tube, and a receiver are connected in a vertical direction, first, all of the ion-exchangeable cations between the layers are made with a 1N ammonium acetate aqueous solution in which layered silicate is adjusted to pH = 7 Is replaced with NH ₄ ⁺ . Then, after thoroughly washing with water and ethyl alcohol, the NH ₄ ⁺ type layered silicate is immersed in a 10% by mass potassium chloride aqueous solution, and NH ₄ ⁺ in the sample is exchanged for K ⁺ . To do. Subsequently, the NH ₄ ⁺ leached with the above-described ion exchange reaction was neutralized and titrated with a 0.1N aqueous sodium hydroxide solution to obtain a cation exchange capacity (milli equivalent / capacity of the swellable layered silicate as a raw material). 100 g).
(2) Inorganic ash content of polyamide resin composition Residue after polyamide resin composition dried pellets or polyamide composite material molded pieces are precisely weighed in a magnetic crucible and incinerated for 15 hours in an electric furnace maintained at 500 ° C. The inorganic ash content was determined according to the following formula.

Inorganic ash (mass%) = {inorganic ash mass (g)} / {total mass of sample before incineration (g)} × 100
(3) Pellet size of polyamide resin and polyamide resin composition 100 pellets of polyamide resin and polyamide resin composition used in the test were extracted, and the diameter and length using calipers on the assumption that the shape was a cylinder. The average volume was calculated from the measurement of (height), and the volume ratio of the polyamide resin and the polyamide resin composition pellets was calculated using the calculated value.
(4) Rigidity of polyamide composite material (flexural modulus)
Measured according to ASTM D-790.
(5) Heat resistance of polyamide composite material (deflection temperature under load)
Based on ASTM D-648, the load was measured at 0.45 MPa.
(6) Impact resistance (surface impact strength) of polyamide composite material
The impact strength was evaluated by dropping a weight from a predetermined height onto a molded product as shown in FIG. 1 using a DuPont impact tester. At this time, the portion directly giving an impact force to the molded product was a disk having a diameter of 30 mm and a thickness of 5 mm, and surface impact was applied. The impact resistance was quantified by calculating the maximum applied energy G (J) at which the molded product did not break under an atmosphere of −30 ° C. under a condition consisting of a combination of a predetermined height and a weight load.

G (J) = (maximum height at which the test piece does not break (m)) × (gravity acceleration (m / sec ² ) × (weight load (g))
Examples 1-3
Using the polyamide composite material having the composition shown in Table 1, various test pieces were injection-molded with an IS-100 molding machine manufactured by Toshiba Machine Co., Ltd., and subjected to tests.

  Table 1 shows the results of measuring various physical properties of the obtained molded product.

In Examples 1 to 3, it can be seen that a polyamide composite material having an excellent balance of impact resistance, rigidity, and heat resistance is obtained, and is sufficiently effective as an improvement of the polyamide resin composition.
Comparative Examples 1-9
Using the polyamide composite material having the composition shown in Table 2, various test pieces were injection-molded with an IS-100 type molding machine manufactured by Toshiba Machine Co., Ltd., and were used for the respective tests.

  The results of measuring various physical properties of the obtained molded product are shown in Table 2.

Comparative Examples 1, 8 and 9 show cases of the polyamide resin composition alone or the polyamide resin alone, respectively, but all tend to lack a balance of material properties. On the other hand, when “standard pellet” or “large-diameter pellet” is used, the effect of improving impact resistance is poor compared to the case of using the above-mentioned “small-diameter pellet”, and the purpose is to improve the polyamide resin composition. It can be said that the effect of the present invention is not exhibited.

It is a perspective view which shows the shape of the test piece used for the impact resistance evaluation test.

Claims (1)

95-50 parts by mass of a polyamide resin composition (A) pellet in which a silicate layer of a swellable layered silicate is dispersed in a polyamide resin at a molecular level, and 5-50 parts by mass of a polyamide resin (B) pellet In the method for producing an injection molded article of a polyamide composite material (C) made of a mixture, the polyamide resin (B) pellets constituting the polyamide composite material per pellet of the polyamide resin composition (A) pellets A method for producing a polyamide composite material injection-molded article , wherein the volume ratio is in the range of 0.2 to 0.9.