JP3452469B2 - Polyamide resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention comprises a reinforced polyamide resin (A) in which 0.1 to 20 parts by weight of a swelling fluoromica mineral is uniformly dispersed and a fibrous reinforcing material (B), and has high rigidity and heat resistance. TECHNICAL FIELD The present invention relates to a polyamide resin composition which has excellent properties and impact resistance and can be formed into a molded article having low warpage.

[0002]

2. Description of the Related Art Polyamide resins are widely used as injection molding materials for parts such as automobiles and home electric appliances, because the molded products have excellent mechanical properties. When imparting high rigidity and heat resistance to a polyamide molded product, a polyamide resin composition reinforced with a fibrous reinforcing material is usually used. For example, glass fibers were mixed in a specific amount as the fibrous reinforcing material. A polyamide resin composition has been proposed (JP-A-51-50960, JP-A-54-188).
54, 59-168058). However, the above-mentioned polyamide resin composition has a problem that when molded by injection molding, the warp of the molded product is large and the dimensional stability is low.

Further, it has been proposed that glass fibers and powdered inorganic substances such as talc are added to a polyamide resin to improve warpage and deformation of molded articles (Japanese Patent Publication No. 58-47).
37, JP-A-51-7056). However, in the polyamide resin composition described here, the addition amount of the glass fiber is 15% by weight or less and the addition amount of the inorganic substance is 20% by weight or more, and since the fibrous reinforcing material is small and the inorganic substance is large, It was difficult to improve rigidity, strength, impact resistance, etc.

Further, a low warpage polyamide resin composition comprising a reinforced polyamide resin in which montmorillonite is uniformly dispersed at the molecular level and a fibrous reinforcing material has been proposed (Japanese Patent No. 2528164). However, even in this case, when the glass fiber content is large, the effect of improving warpage was not sufficient.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a polyamide resin composition having high rigidity, excellent heat resistance and impact resistance, and capable of being a molded article having low warpage.

[0006]

Therefore, as a result of intensive studies, the present inventors have found that a fibrous reinforcing material is added to a reinforced polyamide resin in which a specific amount of swellable fluoromica-based mineral is uniformly dispersed at a molecular level. It has been found that the above problems can be solved by blending a specific amount of the above, and the present invention has been achieved.

That is, the gist of the present invention is as follows. Resin composition in which 50 parts by weight or less of fibrous reinforcing material (B) is mixed with 100 parts by weight of reinforced polyamide resin (A) in which 0.1 to 20 parts by weight of swelling fluoromica mineral is uniformly dispersed at the molecular level. A polyamide resin composition, which has a warp of 2.0 mm or less when formed into a disk having a thickness of 1.6 mm and a diameter of 100 mm.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.

The swellable fluoromica-based mineral according to the present invention
A reinforced polyamide resin composition (A) in which 0.1 to 20 parts by weight is uniformly dispersed at a molecular level (hereinafter referred to as "reinforced polyamide resin composition (A)") is a swellable fluoromica-based mineral in a polyamide resin. Are uniformly dispersed at the molecular level. Here, being uniformly dispersed at the molecular level means that when the swellable fluoromica-based mineral is dispersed in the polyamide matrix, each is kept at an interlayer distance of 20 Å or more on average. Furthermore, the interlayer distance means the distance between the centers of gravity of the flat plates of the silicate layer of the swelling fluoromica-based mineral, and “evenly distributed” means that each silicate layer has 5 layers or each layer has an average overlap. It means a state in which the following multi-layered products are parallel or randomly, or a mixture of parallel and random, and 50% or more, preferably 70% or more thereof are dispersed without forming lumps. Specifically, a wide-angle X-ray diffraction measurement was performed on a test piece of the reinforced polyamide resin composition (A), and the peak due to the thickness direction of the silicate layer disappeared, or a transmission electron micrograph photograph observation Therefore, it can be confirmed from the fact that there is no lump of the swelling fluoromica-based mineral.

The polyamide resin constituting the reinforced polyamide resin (A) in the present invention means a polymer having an amide bond formed from an amino acid, a lactam or a diamine and a dicarboxylic acid (including a pair of salts thereof). To do.

Examples of monomers forming such a polyamide resin are as follows. Examples of amino acids include 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and para-aminomethylbenzoic acid. As lactam, ε-caprolactam, ω
-Laurolactam, etc. As diamine, tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4-
/ 2,4,4-Trimethylhexamethylenediamine, 5-methylnonamethylenediamine, 2,4-dimethyloctamethylenediamine, meta-xylylenediamine, para-xylylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1 -Amino-3-aminomethyl-3,5,5-trimethylcyclohexane, bis (4-aminocyclohexyl)
Methane, bis (3-methyl-4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl)
Examples include propane, bis (aminopropyl) piperazine and aminoethylpiperazine. Examples of the dicarboxylic acid include adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, 2-chloroterephthalic acid, 2-
There are methyl terephthalic acid, 5-methyl isophthalic acid, 5-sodium sulfoisophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, diglycolic acid and the like. Further, these diamine and dicarboxylic acid 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), polyhexamethylene sebacamide (nylon 610). ), Polyhexamethylene dodecamide (nylon 612), polyundecamethylene adipamide (nylon)
116), polyundecane amide (nylon 11), polydodecane amide (nylon 12), polytrimethylhexamethylene terephthalamide (nylon TMDT), polyhexamethylene isophthalamide (nylon 6I), polyhexamethylene terephthal / isophthalamide (nylon 6T) /
6I), polybis (4-aminocyclohexyl) methandodecamide (nylon PACM12), polybis (3-methyl-
4-aminocyclohexyl) methandodecamide (nylon dimethyl PACM12), polymetaxylylene adipamide (nylon MDX6), polyundecamethylene terephthalamide (nylon 11T), polyundecamethylene hexahydroterephthalamide [nylon 11T (H) ] Or a copolymerized polyamide or a mixed polyamide thereof. Of these, nylon 6, nylon 46, nylon 66, nylon 11, nylon 12 or copolyamides or mixed polyamides thereof are preferable, and nylon 6 or nylon 12 or copolyamides thereof are particularly preferable.

The swellable fluoromica-based mineral constituting the reinforced polyamide resin (A) in the present invention is represented by the following formula and can be easily synthesized. α (MF) · β (aMgF ₂ · bMgO) · γSiO ₂ (In the formula, M represents sodium or lithium, and α, β,
γ, a, and b each represent a coefficient, and 0.1 ≤ α ≤ 2, 2 ≤ β
≦ 3.5, 3 ≦ γ ≦ 4, 0 ≦ a ≦ 1, 0 ≦ b ≦ 1, a + b
= 1. )

As a method for producing such a swellable fluoromica-based mineral, for example, silicon oxide, magnesium oxide, and various fluorides are mixed, and the mixture is heated in an electric furnace or a gas furnace at a temperature of 1400 to 1500 ° C. There is a so-called melting method in which a fluorinated mica-based mineral is crystallized in the reaction vessel during the cooling process by completely melting it.

There is also a method in which talc is used as a starting material and alkali metal ions are intercalated into the starting material to obtain a swelling fluoromica-based mineral (Japanese Patent Laid-Open No. 2-1494).
15 publication). In this method, talc contains a fluorosilicate and / or
Alternatively, a swellable fluoromica-based mineral can be obtained by mixing a fluoride and heat-treating at 700 to 1200 ° C for a short time in a magnetic crucible. The swellable fluoromica-based mineral used in the present invention is particularly preferably one produced by this method.

At this time, the amount of alkali silicofluoride or alkali fluoride mixed with talc is 10 to 35 of the total mixture.
It is preferable to set the content in the range of wt%, and if it is out of this range, the production yield of the swelling fluoromica-based mineral is lowered, which is not preferable.

In order to obtain the above-mentioned swellable fluoromica-based mineral, it is necessary that the alkali metal silicofluoride or alkali metal fluoride is sodium or lithium. These alkali metals may be used alone or in combination. Further, of the alkali metals, potassium does not give a swelling fluoromica-based mineral, but it can be used in combination with sodium or lithium, and can be used for the purpose of adjusting the swelling property in a limited amount. Is.

Further, in the step of producing the swellable fluoromica-based mineral, it is possible to blend a small amount of alumina to adjust the swellability of the swellable fluoromica-based mineral produced.

The blending amount of the swelling fluoromica-based mineral is based on the amount of the monomers forming 100 parts by weight of the polyamide resin.
It is necessary to use 0.1 to 20 parts by weight. This blended amount
If the amount is less than 0.1 parts by weight, a resin composition that has high rigidity, excellent heat resistance and impact resistance, and can be formed into a molded article having low warpage cannot be obtained. On the other hand, if the blending amount exceeds 20 parts by weight, the toughness of the molded product is greatly deteriorated, which is not preferable.

Next, a method for producing the reinforced polyamide resin (A) will be described. For that purpose, first, the swelling fluoromica-based mineral is mixed with the amount of the monomer forming 100 parts by weight of the polyamide resin, and the monomer is polymerized under pressure. At this time, the polymerization is preferably carried out at a temperature of 240 to 300 ° C. and a pressure of ^{2 to} 30 kg / cm ² for 1 to 5 hours.

Next, the reinforced polyamide resin (A) is pelletized by maintaining the above temperature, returning to normal pressure, discharging the produced reinforced polyamide resin in a strand form, cooling, solidifying and cutting. And

An acid may be added during the above-mentioned polymerization, and by adding the acid, a molded product having higher rigidity and higher heat resistance can be obtained.

The above-mentioned acid may be either an organic acid or an inorganic acid as long as it has a pKa (value in water at 25 ° C., water) of 0 to 4 or a negative acid. For example, benzoic acid, sebacic acid, Formic acid, acetic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, trifluoroacetic acid, nitrous acid, nitric acid, phosphoric acid, phosphorous acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, perchloric acid, fluorosulfonic acid -Pentafluoroantimony (1: 1) [Aldrich's "Magic Acid"
(Registered trademark)], fluoroantimonic acid, and the like.

The relative viscosity of the polyamide resin constituting the reinforced polyamide resin (A) of the present invention is a value obtained by using 96% by weight concentrated sulfuric acid as a solvent at a temperature of 25 ° C. and a concentration of 1 g / dl.
It is preferably in the range of 1.5 to 5.0. When the relative viscosity is less than 1.5, the mechanical properties of the molded product deteriorate. On the other hand, when the relative viscosity is more than 5.0, the moldability of the resin composition is rapidly lowered, which is not preferable.

The fibrous reinforcing material (B) in the present invention is a component which, when mixed with the reinforced polyamide resin (A), can be a molded product having high rigidity, excellent heat resistance and low warpage. . The amount of the fibrous reinforcing material (B) blended should be 50 parts by weight or less with respect to 100 parts by weight of the reinforced polyamide resin (A). If the blending amount exceeds 50 parts by weight, the fluidity of the resin composition is lowered, the surface of the molded product is not finished smoothly, and a molded product having an excellent appearance cannot be obtained.

As the fibrous reinforcing material (B), glass fiber,
Carbon fibers, ceramic whiskers such as wollastonite, silicon nitride, potassium titanate, basic magnesium sulfate, sepiolite, zonotlite, aluminum borate, etc. can be mentioned, among which glass fiber, carbon fiber, potassium titanate whiskers are preferable. Glass fiber is particularly preferable.

The above fibrous reinforcing material has an average diameter (D) of 0.2 in the polyamide resin composition after melt kneading.
~ 20 μm and the ratio of average length (L) to average diameter (D),
It is preferable that L / D is 10 to 90. If the average diameter (D) is less than 0.2 μm, it is difficult to mass-produce industrially, and if the average diameter (D) exceeds 20 μm, a molded article having low warpage cannot be obtained. If the L / D is less than 10, it is difficult to obtain a molded product with high rigidity and excellent heat resistance, and if the L / D is more than 90, it is difficult to obtain a molded product with low warpage.

At this time, when the fibrous reinforcing material is glass fiber or carbon fiber, the glass fiber and the carbon fiber are broken in the extruder when melt-kneading with the reinforced polyamide resin, so that the fiber-reinforced material is melt-kneaded. Prior to, a preliminary test is performed in consideration of the extruder and its screw shape, and L / D in the polyamide resin composition after melt kneading is 10 to
The length of the glass fiber or carbon fiber may be appropriately determined so as to be 90. Further, when the fibrous reinforcing material is a ceramic whisker such as potassium titanate, it is not necessary to perform such a test because breakage rarely occurs during melt kneading.

In order to produce the polyamide resin composition of the present invention, a pellet of the reinforced polyamide resin (A) and the fibrous reinforcement (B) are usually used by using a twin-screw extruder equipped with a screw. After melt-kneading and are extruded into strands, a method of forming pellets is adopted.

Further, the thermoplastic resin composition of the present invention may be mixed with another thermoplastic polymer, and in this case also, a twin-screw extruder equipped with a screw is used for mixing and alloying. It is preferable. In such a resin composition, since the swellable fluoromica-based mineral is uniformly dispersed in the polyamide resin at the molecular level, mechanical strength and heat resistance are improved as compared with an alloy with a non-reinforced polyamide resin.

Examples of the above-mentioned thermoplastic polymers include polybutadiene, butadiene / styrene copolymer, acrylic rubber, ethylene / propylene copolymer, ethylene / propylene / diene copolymer, natural rubber, chlorinated butyl rubber, chlorinated. Elastomers such as polyethylene or acid modified products of these with maleic anhydride, styrene / maleic anhydride copolymer, styrene / phenylmaleimide copolymer, polyethylene, polypropylene, butadiene /
Acrylonitrile copolymer, polyvinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyacetal, polyvinylidene fluoride, polysulfone,
Polyphenylene sulfide, polyether sulfone,
Examples thereof include phenoxy resin, polyphenylene ether, polymethylmethacrylate, polyetherketone, polycarbonate, polytetrafluoroethylene, polyarylate and the like. At this time, the thermoplastic polymer is preferably mixed in a ratio of 60 parts by weight or less with respect to 100 parts by weight of the reinforced polyamide resin (A).

The polyamide resin composition of the present invention contains a pigment, a heat stabilizer, an antioxidant, a deterioration inhibitor, a weatherproofing agent, a flame retardant, a plasticizer, a release agent, etc., unless the characteristics are significantly impaired. May be added, these are reinforced polyamide resins
It is added during the polymerization of (A) or during the melt kneading or melt molding of the obtained polyamide resin composition.

As the heat stabilizer, antioxidant and deterioration inhibitor, for example, hindered phenols, phosphorus compounds, hindered amines, sulfur compounds, copper compounds, alkali metal halides or mixtures thereof can be used. .

The polyamide resin composition of the present invention can be made into a desired molded product by an ordinary molding method, and various molded products can be obtained by a hot melt molding method such as injection molding, extrusion molding, blow molding or the like. A thin film can be formed by a casting method using an organic solvent solution.

Molded articles obtained by using the polyamide resin composition of the present invention have a small warpage, mechanical strength, heat resistance and dimensional stability are remarkably improved as compared with the case where the polyamide resin is used alone. Since there are few mechanical properties and dimensional changes, various molded products can be obtained.

The above-mentioned molded products include pipes, hollow pipes, handles, ink containers, curtain rails, gear parts,
Bearing retainers, brushes, reels, breaker covers, switches, connectors, automobile exterior parts, automobile interior parts, light covers, intake manifolds, timing belt covers, wheels, engine covers, cylinder head covers and the like can be mentioned. However, it is not limited to these, excellent low warpage characteristic which is a characteristic of the polyamide resin composition of the present invention,
It can be widely used in fields where mechanical strength and heat resistance can be utilized.

[0037]

EXAMPLES Next, the present invention will be described more specifically by way of examples. The raw materials used in the examples and comparative examples and the measurement methods for the physical property tests are as follows. 1. Raw material (1) Talc crushed to an average particle size of 4 μm by a swelling fluoromica-based mineral ball mill was mixed with sodium fluorinated silica having an average particle size of 4 μm to 15% by weight of the total amount. This was placed in a magnetic crucible and reacted in an electric furnace at 850 ° C for 1 hour for synthesis. Wide-angle X-ray diffraction measurement of this powder showed that the thickness of the raw talc was 9.2 in the c-axis direction.
The peak corresponding to Å disappeared, and peaks corresponding to 12 to 13 Å indicating the formation of swelling fluoromica minerals were observed. (2) Montmorillonite Commercially available montmorillonite (Kunipia F, manufactured by Kunimine Industries Co., Ltd.) was swelled with 12-aminododecanoic acid hydrochloride in water, filtered, washed with water, dried and pulverized.
As a result of wide-angle X-ray diffraction measurement of this powder, it was confirmed that the thickness of montmorillonite in the c-axis direction increased from 12Å to 17Å, and that 12-aminododecanoic acid was inserted between the layers of montmorillonite.

2. Measurement method (a) using a dispersive wide-angle X-ray diffractometer (RAD-rB type manufactured by Rigaku Corporation) of a swelling fluoromica-based mineral or montmorillonite in a polyamide resin composition,
Wide-angle X-ray diffraction measurement was performed on a test piece for bending strength measurement, and the dispersibility of the swelling fluoromica-based mineral or montmorillonite was measured. (b) The polymer component in the relative viscosity test piece of the polyamide resin is 96 wt% concentrated sulfuric acid,
The solution was prepared to have a concentration of 1 g / dL. The swelling fluoromica-based mineral or montmorillonite in the test piece was determined by burning the test piece at 500 ° C for 24 hours and then measuring the ash content. The solution prepared above is
After centrifugation at rpm for 2 hours, the supernatant was filtered through a G-3 glass filter and subjected to viscosity measurement. The measurement was performed at 25 ° C. (c) Size of fibrous reinforcing material in polyamide resin composition (L, D, L / D) Average length of fibrous reinforcing material in polyamide resin composition (L)
, Average diameter (D) and its ratio (L / D) were determined as follows. That is, a total of 1 g of the molded product was sampled from three locations, dissolved in formic acid, sandwiched with a slide glass, and taken with a microscope magnification photograph of 30 times for glass fiber and carbon fiber and 300 times for potassium titanate whiskers. n number
The length of the fibrous reinforcement was measured at 200. Its average length L
25 μm for glass fiber and carbon fiber
For the intervals and potassium titanate whiskers, a frequency distribution table was prepared at intervals of 1 μm, and (central value of each grade) × (frequency)
Was calculated, and the value obtained by adding this was divided by the total frequency. Therefore, it is represented by L = Σ [(central value of each class) × (frequency)] / total frequency. In the same manner, 300 times of magnified micrographs of glass fibers and carbon fibers and 10000 times of electron micrographs of potassium titanate whiskers were taken.
The diameter of the fibrous reinforcing material was measured by the number 10, and the average diameter D was calculated by the arithmetic mean. L / D is the ratio of L and D described above. (d) A disk having a thickness of 1.6 mm and a diameter of 100 mm obtained by warpage injection molding of a disk was placed under the horizontal plane, and the maximum clearance between the disk and the horizontal plane was shown. (e) Tensile strength and tensile breaking elongation of the test piece were measured based on ASTM D-638. (f) Bending strength and flexural modulus of the test piece It was measured based on ASTM D-790. (g) Izod impact strength of test piece Based on ASTM D-256, a 3.2 mm-thick test piece was measured with a notch having a predetermined depth. (h) The heat distortion temperature of the test piece was measured at a load of 1.86 MPa based on ASTM D-648.

Example 1 ε-caprolactam 10 kg, swelling fluoromica mineral 0.5 k
g and 1 kg of water were placed in a reactor having an internal capacity of 30 liters, and the pressure was raised to 15 kg / cm ² with stirring. Then, while gradually releasing the pressure of steam, the pressure was kept at 15 kg / cm ² and the temperature was 260 ° C. for polymerization for 2 hours, and then the pressure was released to normal pressure over 1 hour.
Then, after leaving it at 260 ° C. for 30 minutes under normal pressure, it was discharged in a strand form, cooled, solidified, and cut to obtain pellets of a reinforced polyamide resin (A) composed of a swellable fluoromica-based mineral and a nylon 6 polymer. . Then, this pellet
Scouring was carried out with hot water at 95 ° C. for 8 hours, this operation was repeated twice, and vacuum drying was performed. And this dried pellet 100
A twin-screw extruder with an inner diameter of 35 mm (made by Ikegai Iron Works Co., Ltd.), in which 25 parts by weight of glass fiber (manufactured by Nippon Electric Glass Co., Ltd., T-289, average diameter: 13 μm, average length: 3000 μm) were set at a cylinder temperature of 260 ° C. , PCM-45) and melt-kneaded at 260 ° C., and then extruded in the form of strands to form pellets and vacuum-dried. The glass fiber is a molten reinforced polyamide resin.
(A) was added from a popper. Then, using an injection molding machine (manufactured by Mitsubishi Heavy Industries, Ltd., 125 / 75MS type), the dry pellets were subjected to a cylinder temperature of 260 ° C, a mold temperature of 70 ° C, and an injection time of 6
Seconds, cooling time was 6 seconds, injection molding was carried out, various test pieces having a thickness of 3.2 mm were prepared, and physical properties were tested.

Example 2 Except that 50 parts by weight was used instead of 25 parts by weight of glass fiber,
Dry pellets and various test pieces were prepared in the same manner as in Example 1, and the physical properties were tested.

Example 3 Instead of 25 parts by weight of glass fiber, potassium titanate whiskers (manufactured by Otsuka Chemical Co., Tismo D102, average diameter 0.3 μm)
m, average length 13 μm) except that 25 parts by weight was used.
Dry pellets and various test pieces were prepared in the same manner as above, and the physical properties were tested.

Example 4 Instead of 25 parts by weight of glass fiber, potassium titanate whiskers (manufactured by Otsuka Chemical Co., Ltd., Tismo D102, average diameter 0.3 μm)
m, average length 13 μm) except that 50 parts by weight was used.
Dry pellets and various test pieces were prepared in the same manner as above, and the physical properties were tested.

Example 5 Instead of 25 parts by weight of glass fiber, carbon fiber (M-102S manufactured by Kureha Chemical Co., Ltd., average diameter 14.5 μm, average length 200 μm) 25
Dry pellets and various test pieces were prepared in the same manner as in Example 1 except that parts by weight were used, and a physical property test was conducted.

Example 6 Instead of 25 parts by weight of glass fiber, carbon fiber (M-102S manufactured by Kureha Chemical Co., Ltd., average diameter 14.5 μm, average length 200 μm) 50
Dry pellets and various test pieces were prepared in the same manner as in Example 1 except that parts by weight were used, and a physical property test was conducted.

Table 1 shows the blending ratios of polyamide resin compositions, relative viscosities, sizes of fibrous reinforcing materials, disk warpage and physical properties of various test pieces in Examples 1 to 6.

[0046]

[Table 1]

Comparative Example 1 10 kg of ε-caprolactam, 0.5 kg of montmorillonite with 12-aminododecanoic acid inserted between layers and 1 kg of water
The mixture was put into a 30-liter reaction can and the pressure was raised to 15 kg / cm ² while stirring. And gradually releasing the steam,
After polymerizing for 2 hours at a pressure of 15kg / cm ² and a temperature of 260 ℃,
The pressure was released to normal pressure over 1 hour. Then, under normal pressure, 260
After leaving at 30 ° C. for 30 minutes, it was discharged in a strand form, cooled, solidified, and cut to obtain pellets of a reinforced polyamide resin (A) composed of montmorillonite and nylon 6 polymer. Next, the pellets were scoured with hot water at 95 ° C. for 8 hours, this operation was repeated twice, and then vacuum dried. And 100 parts by weight of the dried pellets and glass fiber (T-289, manufactured by Nippon Electric Glass Co., average diameter 13 μm, average length 3000)
μm) 25 parts by weight using a twin-screw extruder (PCM-45 manufactured by Ikegai Tekko Co., Ltd.) with an inner diameter of 35 mm and a cylinder temperature set to 260 ° C., melt-kneaded at 260 ° C., and then extruded in a strand form. Pelletized and vacuum dried. The glass fibers were added to the molten reinforced polyamide resin (A) from the popper. After that, using an injection molding machine (Mitsubishi Heavy Industries Ltd., 125 / 75MS type), the dry pellets were heated to a cylinder temperature of 260 ° C,
Injection molding was performed at a mold temperature of 70 ° C., an injection time of 6 seconds, and a cooling time of 6 seconds to prepare various test pieces having a thickness of 3.2 mm, and the physical properties were tested.

Comparative Example 2 Instead of 25 parts by weight of glass fiber, potassium titanate whiskers (manufactured by Otsuka Chemical Co., Ltd., Tismo D102, average diameter 0.3 μm)
m, average length 13 μm) Comparative Example 1 except that 25 parts by weight was used.
Dry pellets and various test pieces were prepared in the same manner as above, and the physical properties were tested.

Comparative Example 3 Instead of 25 parts by weight of glass fiber, carbon fiber (M-102S, manufactured by Kureha Chemical Co., Ltd., average diameter 14.5 μm, average length 200 μm) 25
Dry pellets and various test pieces were prepared in the same manner as in Comparative Example 1 except that parts by weight were used, and a physical property test was conducted.

Comparative Example 4 Dry pellets and various test pieces were prepared in the same manner as in Comparative Example 1 except that a nylon 6 resin having a relative viscosity of 2.6 (A1030BRL manufactured by Unitika Ltd.) was used in place of the reinforced nylon 6 resin (A). Was prepared and a physical property test was conducted.

Comparative Example 5 Nylon 6 resin (A1030BRL manufactured by Unitika Ltd.) having a relative viscosity of 2.6 was used instead of the reinforced nylon 6 resin (A), and potassium titanate whiskers (Tismo D102 manufactured by Otsuka Chemical Co., Ltd.) were used instead of the glass fiber. , Average diameter 0.3μm, average length 13μ
Dry pellets and various test pieces were prepared in the same manner as in Comparative Example 1 except that m) was used, and the physical properties were tested.

Comparative Example 6 Nylon 6 resin having a relative viscosity of 2.6 (A1030BRL manufactured by Unitika Ltd.) was used instead of the reinforced nylon 6 resin (A), and carbon fiber (M-102S manufactured by Kureha Chemical Co., Ltd.) was used instead of the glass fiber. Dry pellets and various test pieces were prepared in the same manner as in Comparative Example 1 except that an average diameter of 14.5 μm and an average length of 200 μm) were used, and a physical property test was performed.

Table 2 shows the blending ratios of the polyamide resin compositions, relative viscosities, sizes of fibrous reinforcing materials, disk warpage and physical properties of various test pieces in Comparative Examples 1 to 6.

[0054]

[Table 2]

In Examples 1 to 6 and Comparative Examples 1 to 3, wide angle X-ray diffraction measurement was performed on the test pieces for measuring bending strength. As a result, the peaks in the thickness direction of the swelling fluoromica-based mineral or montmorillonite were completely It was found that the swellable fluoromica mineral or montmorillonite was uniformly dispersed in nylon 6 at the molecular level.

[0056]

EFFECTS OF THE INVENTION According to the present invention, it is possible to obtain a polyamide resin composition having high rigidity, excellent heat resistance and impact resistance, and capable of forming a molded article having low warpage.

Claims (3)

(57) [Claims] 1. A reinforced polyamide resin in which 0.1 to 20 parts by weight of a swelling fluoromica-based mineral is uniformly dispersed at a molecular level.
(A) 100 parts by weight, fibrous reinforcing material (B) is a resin composition containing 50 parts by weight or less, thickness 1.6 mm, diameter 1
A polyamide resin composition having a warp of 2.0 mm or less when formed into a disk of 00 mm. 2. The average diameter (D) of the fibrous reinforcement is 0.2 to 20.
μm and the ratio of average length (L) to average diameter (D), L / D
Is 10 to 90, The polyamide resin composition according to claim 1, wherein 3. The polyamide resin composition according to claim 1, wherein the fibrous reinforcing material is glass fiber.