JPH11279402A - Fibrous xonotlite-reinforced polyamide resin composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a fibrous xonotlite-reinforced polyamide resin composition good in dispersion of the fibrous xonotlite after melt kneading and having a controlled aspect ratio and to provide a method for producing the polyamide resin composition. SOLUTION: A fibrous xonotlite in an amount so as to provide a volume fraction ϕ of 0<ϕ<=0.310 can be compounded with a polyamide resin and the melt kneading can then be carried out at a specific energy ratio within the range represented by A<Esp(ϕ)/Esp(0)<=B [A=1+1.028ϕ/(1-3.058ϕ); B=1+3.391ϕ/(1-2.921ϕ); ϕ denotes the volume fraction of the fibrous xonotlite in a polyamide resin composition; 0<ϕ<=0.310; Esp(ϕ) denotes the specific energy of the polyamide resin composition containing the fibrous xonotlite in the volume fraction ϕ at the time of melt kneading; Esp(0) denotes the specific energy of the simple polyamide resin at the time of melt kneading] to thereby produce the fibrous xonotlite-reinforced polyamide resin composition containing the fibrous xonotlite uniformly dispersed therein, having an aspect ratio within the range of 7-20 and good in mechanical strengths with good reproducibility.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin composition obtained by melt-kneading a polyamide resin and a fibrous zonotolite, and a method for producing the same. More particularly, the present invention relates to a polyamide resin composition containing a specific amount of a fibrous zonotlite having a specific aspect ratio obtained by melt-kneading and having excellent mechanical properties, and a method for producing the same. The fibrous zonotolite-reinforced polyamide resin composition obtained by melt-kneading has excellent mechanical strength and is used for applications such as automobile parts, electric / electronic parts, construction parts, and mechanical parts.

[0002]

2. Description of the Related Art A resin composition comprising a thermoplastic resin such as a polyamide resin and fibrous zonotolite is disclosed in, for example, JP-A-6-128412 and JP-A-7-216.
No. 133 and Japanese Patent Application No. 8-170015 disclose a resin composition having excellent mechanical strength and heat resistance. According to these, the fibrous zonotolite has a large effect of improving the mechanical strength of the polyamide resin as compared with a glass fiber as a typical fibrous reinforcing material.

In general, a resin composition comprising a resin and a fibrous reinforcing material has properties such as mechanical strength and the like, as the content of the fibrous reinforcing material increases, the dispersibility improves, and the aspect ratio increases. Is known to be better. However, it is very difficult to simultaneously optimize the content, dispersibility, and aspect ratio of the fibrous reinforcement. For example, when melt-kneading a resin and a fibrous reinforcing material, the melt viscosity increases when the content of the fibrous reinforcing material increases, and the dispersibility of the fibrous reinforcing material deteriorates, or the aspect ratio decreases. . Further, when melt-kneading under conditions that improve dispersibility, the content of the fibrous reinforcing material is limited, and the aspect ratio is reduced. Usually, the melt-kneading conditions of the fiber-reinforced resin are often determined empirically, and if the melt-kneading apparatus is different, the optimum melt-kneading conditions are different, and the mechanical strength of the obtained fiber-reinforced resin composition is also different.

[0004] In the melt-kneading of a polyamide resin and a fibrous zonotolite, in many cases, experiments have been repeated, and the melt-kneading conditions considered to be optimal from experience have been determined.
The fibrous zonotolite is mainly composed of an aggregate in which a plurality of fibers are gathered in a bundle, and since the aggregate has a strong cohesive force between the fibers and exists in a relatively stable state,
Usually, agglomerates are handled as a single fiber. But,
When a large shear force is applied during melt kneading or the like, the aggregate is decomposed or cut, and the diameter or length of the aggregate changes. Therefore, it is difficult to control the dispersibility and aspect ratio of the fibrous zonotolite after melt-kneading as compared with other fibrous reinforcing materials such as glass fibers, and the mechanical strength of the obtained fiber-reinforced resin composition tends to have a large variation width. ,
There was a problem with reproducibility. Therefore, it has been required to clarify the optimum aspect ratio of the fibrous zonotolite in the resin composition comprising the polyamide resin obtained by melt-kneading and the fibrous zonotolite and to establish a control method thereof.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a fibrous zonotolite-reinforced polyamide resin composition having a good dispersion of fibrous zonotolite after melt-kneading and having a controlled aspect ratio, and a process for producing the same. .

[0006]

Means for Solving the Problems In order to solve the problems of the present invention, the relationship between the dispersibility and aspect ratio of the fibrous zonotolite in the melt-kneaded product comprising a polyamide resin and fibrous zonotolite and the conditions of the melt-kneading are described in detail. As a result of the examination,
As a specific amount of the content of the fibrous zonotolite in the melt-kneaded material, by melt-kneading at a specific specific energy, the fibrous zonotolite after melt-kneading is uniformly dispersed,
The inventors have found that the aspect ratio can be controlled to a specific range, and have reached the present invention.

That is, the first invention of the present invention is a melt-kneaded product of a polyamide resin and a fibrous zonotolite, wherein the volume fraction of the fibrous zonotolite in the melt-kneaded material is φ
Is 0 <φ ≦ 0.310 and the aspect ratio is 7
A fibrous zonotolite-reinforced polyamide resin composition in the range of -20 to 20.

According to a second aspect of the present invention, there is provided a fibrous zonotlite melt-kneaded with a polyamide resin, wherein (a) 0.1 μm ≦
d <0.5 μm, (b) 1 μm ≦ l <5 μm and
(C) 10 ≦ l / d <20 (where d and l indicate the average fiber diameter and average fiber length of the fibrous zonotolite before melt kneading, respectively), and the fibrous zonotolite Is the specific energy Esp (φ) of the polyamide resin composition containing φ in a volume fraction at the time of melt-kneading and the specific energy Esp (0) of the polyamide resin alone at the time of melt-kneading, which is Esp (φ) / Esp (0). Is the equation (1)

A <Esp (φ) / Esp (0) ≦ B (1) (where A = 1 + 1.028φ / (1-3.058φ), B = 1 +
3.391φ / (1-2.921φ), φ represents the volume fraction of fibrous zonotolite in the polyamide resin composition, and 0 <φ ≦ 0.3
The value is in the range of 10. This is a method for producing a fibrous zonotolite-reinforced polyamide resin composition according to the first invention, which is melt-kneaded under the conditions satisfying (1).

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The fibrous zonotolite used in the present invention is zonotolite (having a chemical formula: Ca ₆ Si ₆ O ₁₇ (OH) ₂ , a chemical formula:
6CaO · 6SiO ₂ · H ₂ O)
For example, a method described in JP-A-6-128412, a method in which a calcareous material such as quicklime and a siliceous material such as silicic acid are mixed at a weight ratio of calcium / silane of 0.8 to 0.99 and water It can be produced by a thermal synthesis reaction.

In the present invention, the fibrous zonotolite melt-kneaded with the polyamide resin has an average fiber diameter d of 0.1 μm ≦ d <
0.5 μm, the average fiber length l is 1 μm ≦ l <5 μm, and the aspect ratio l / d satisfies the condition of 10 ≦ l / d <20 at the same time.

[0011] As described above, fibrous zonotolite is mainly composed of aggregates in which a plurality of fibers are gathered in a bundle, and the aggregates of the fibers are strong, and the aggregates have an external force of a certain magnitude or more. Unless added, exists in a stable state. Therefore, the average fiber diameter d and the average fiber length 1 used in the present invention, the aggregate diameter is regarded as one fiber, the apparent diameter and length of the aggregate, the fiber diameter and the fiber length of one fiber, respectively It is a value that is measured and determined as long.

When the aspect ratio of the fibrous zonotolite melt-kneaded with the polyamide resin is smaller than 10, the aspect ratio of the fibrous zonotolite in the obtained melt-kneaded product becomes excessively small, and the effect of improving the mechanical strength becomes insufficient. . On the other hand, if the aspect ratio is larger than 20, the melt viscosity becomes high, and melt kneading becomes difficult.
When the average fiber diameter d is less than 0.1 μm or 0.5 μm or more and the average fiber length 1 is less than 1 μm or 5 μm or more, the fibrous zonotolite is easily broken at the time of melt-kneading the polyamide resin and the fibrous zonotolite, Many of the fibrous zonotolites after melt-kneading have an aspect ratio of less than 7.

The fibrous zonotolite used in the present invention comprises:
Known surfactants such as anionic surfactants, cationic surfactants, amphoteric surfactants and nonionic surfactants, and silane-based surfactants are used to increase the affinity with the polyamide resin. Coupling agents, titanate-based coupling agents, aluminum-based coupling agents, chromium-based coupling agents, those that have been surface-treated with a known coupling agent such as a boron-based coupling agent are preferable,
used.

The amount of these surfactants and coupling agents used is 0.1 to 10% by weight, preferably 0.5 to 8% by weight, based on the fibrous zonotolite (dry matter weight basis). In addition, for the purpose of facilitating melt-kneading with a polyamide resin, fibrous zonotolite obtained by granulating into granules can also be used.

The fibrous zonotolite in the fibrous zonotolite-reinforced polyamide resin composition obtained by melt-kneading of the present invention has a volume fraction φ of 0 <φ ≦ 0.310, preferably
0.005 <φ ≦ 0.310, more preferably 0.01
4 <φ ≦ 0.230, and the aspect ratio of the fibrous zonotolite is in the range of 7 to 20, preferably 8 to 18. The volume fraction φ of the present invention is a value obtained by dividing the volume of the fibrous zonotolite used by the total volume, that is, the sum of the volume of the polyamide and the volume of the fibrous zonotolite. For example, the volume fraction of the fibrous zonotolite in the melt-kneaded product obtained by melt-kneading nylon 6 and the fibrous zonotolite is as follows. Is measured, and the specific gravity of the fibrous zonotolite is set to 2.48, and the specific gravity of nylon 6 is set to 1.14.

[Equation 3] Volume fraction (%) = (X / 2.48) / ((X / 2.48) + (C−X) /1.14) (2) (where X is the weight of the fibrous zonotolite (g) ) And C are the weight (g) of the resin composition.) When the volume fraction of the fibrous zonotolite is within the above range, the dispersibility of the fibrous zonotolite in the polyamide resin composition kneaded under the melt-kneading conditions of the present invention. Is good. Further, when the volume fraction is more than 0.310, the melt viscosity of the resin composition becomes high, and the dispersibility of the fibrous zonotolite tends to deteriorate,
The mechanical properties of the resulting fibrous zonotolite-reinforced polyamide resin composition are reduced or reproducibility is poor.

The volume fraction φ of the fibrous zonotolite is 0
Even if <φ ≦ 0.310, if the aspect ratio is smaller than 7, the mechanical strength is low. On the other hand, when the aspect ratio is larger than 20, the melt viscosity of the polyamide resin composition becomes high, and the dispersibility of the fibrous zonotolite tends to be deteriorated even when melt-kneaded under the specific energy conditions of the present invention.

The polyamide resin used in the present invention is a known one, and is a polyamide obtained by ring-opening polymerization of a cyclic aliphatic lactam having three or more rings, and a polyamide obtained by polycondensing a diamine and a dicarboxylic acid. And polyamides obtained by polycondensation of ω-amino acids, and copolymerized polyamides obtained by copolymerizing two or more of the above polyamides. Further, the above polyamide resins may be used alone or in combination of two or more.

Specific examples of the cyclic aliphatic lactam having three or more rings include ε-caprolactam, ω-enantholactam, α-pyrrolidone, δ-methylpyrrolidone, α-piperidone, ω-undecanelactam and ω-dodecalactam. Can be mentioned. These cycloaliphatic lactams may be used alone or in combination of two or more.

Specific examples of the diamine include hydrazine,
Ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexa Methylene diamine,
2,4,4-trimethylhexamethylenediamine, 2-
Aliphatic diamines such as methylhexamethylenediamine, 3-methylhexamethylenediamine, 2-ethyloctamethylenediamine and 3-t-butylhexamethylenediamine; 1,3-diaminocyclohexane;
Diaminocyclohexane, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, isophoronediamine, piperazine, N-
Diamines such as aminoethylpiperazine, 2,5-dimethylpiperazine, bis (p-aminocyclohexyl) methane and 2,2-bis- (4-aminocyclohexyl) propane, and m-xylylenediamine;
-Aromatic diamines such as xylylenediamine. The above diamine may be used alone,
Two or more kinds may be used in combination.

Specific examples of dicarboxylic acids include oxalic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, 3-methyladipic acid, 3-t-butyladipic acid, pimelic acid, suberic acid, azelaic acid Acid, sebacic acid, nonandionic acid, decanedioic acid, undecandioic acid, dodecandionic acid, tridecandionic acid, tetradecandionic acid, pentadecandionic acid, hexadecandionic acid, dimeric dicarboxylic acid of eicosandioic acid, lindelic acid and Aliphatic dicarboxylic acids such as dicarboxylic acid of dimer of oleic acid, alicyclic dicarboxylic acids such as 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid, terephthalic acid, Isophthalic acid, 5-t
-Butyl isophthalic acid, 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid,
1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,
3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,3-
Anthracene dicarboxylic acid, 1,4-anthracene dicarboxylic acid, 1,5-anthracene dicarboxylic acid, 1,9
-Anthracene dicarboxylic acid, 2,3-anthracene dicarboxylic acid, 9,10-anthracene dicarboxylic acid, biphenyl-2,2-dicarboxylic acid, biphenyl-2,3
-Dicarboxylic acid and 3- (4-carboxyphenyl)
Examples thereof include aromatic dicarboxylic acids such as 1,1,3-indanecarboxylic acid. These dicarboxylic acids may be used alone or in combination of two or more.

Specific examples of the salt obtained from the above diamine and dicarboxylic acid include ethylene diammonium adipate, tetramethylene diammonium adipate, tetramethylene diammonium pimerate, tetramethylene diammonium azelate, and pentamethylene diammonium sebacate. Kate, hexamethylene diammonium adipate, hexamethylene diammonium sebacate, hexamethylene diammonium succinate, octamethylene diammonium adipate, octamethylene diammonium sebacate, nonamethylene diammonium adipate, octamethylene diammonium sebacate, deca Methylene diammonium adipate, undecamethylene diammonium sebacate, dodecamethylene diammonium adipate, It can be mentioned the diamine and equimolar salt obtained from the above dicarboxylic acids such as decamethylene diammonium sebacate and m- xylylene ammonium adipate.

Specific examples of the ω-aminocarboxylic acid include:
ε-aminocaproic acid, ω-aminoheptanoic acid, ω-aminononanoic acid, ω-aminoundecanoic acid, ω-aminododecanoic acid, and the like. These ω-
Only one aminocarboxylic acid may be used alone,
Two or more kinds may be used in combination.

Specific examples of the polyamide resin include nylon 4, nylon 6, nylon 9, nylon 11, nylon 12,
Aliphatic polyamides such as nylon 46, nylon 66, nylon 610, and nylon 612, polyhexamethylene terephthalamide (nylon 6T), polyhexamethylene isophthalamide (nylon 6I), polymethaxylene adipamide (nylon MXD6); Semi-aromatic polyamides such as polymetaxylene veramide (nylon MXD8), polymetaxylene sebacamide (nylon MXD10), polyparaxylene adipamide (nylon PXD6), polyparaxyleneazeramide (nylon PXD9), Examples thereof include copolymers and mixtures of polyamides. Among these, nylon 6, nylon 6
6, a copolymer of nylon 12, nylon 6, and nylon 66, a terpolymer of nylon 6, nylon 66, and nylon 12, a copolymer of nylon 66 and nylon 6T, and the like can be preferably used. Further, the nylon resin used in the present invention has no particular restrictions on the type and concentration of the terminal group, the molecular weight and the molecular weight distribution.

Further, various sub-materials usually added to the resin for improving the properties and the production of the polyamide resin composition comprising the polyamide resin and the fibrous zonotolite as long as the effects of the present invention are not impaired, , Heat stabilizers, ultraviolet absorbers, light stabilizers, antioxidants, antistatic agents, lubricants, antiblocking agents, tackifiers, sealability improvers, antifoggants, crystal nucleating agents, mold release agents, In addition to additives and modifiers such as impact modifiers, plasticizers, crosslinking agents, foaming agents, flame retardants, flame retardant aids, pigments, dyes, and fragrances, fillers and reinforcing materials can be added. .

If necessary, a thermoplastic resin other than the polyamide resin, a thermoplastic elastomer, and rubbers may be added in an amount of up to 40% by weight based on the polyamide resin. Specific examples of the thermoplastic resin include polyethylene, polypropylene-based polymer, polybutene-1,
Examples include poly-4-methylpentene-1, an ABS resin, and polyphenylene ether. Examples of the thermoplastic elastomer and rubbers include ethylene propylene rubber, ionomer, styrene / butadiene / styrene elastomer, styrene / ethylene / butadiene / styrene elastomer, and the like.

The volume fraction φ of the fibrous zonotolite of the present invention
Is 0 <φ ≦ 0.31, the dispersibility is good, and the aspect ratio is in the range of 7 to 20. For example, a polyamide resin and a fibrous zonotolite will be described below. It can be produced by melt-kneading under the conditions.

That is, a polyamide resin composition containing fibrous zonotolite in a range where the volume fraction φ is 0 <φ ≦ 0.31 is heated to a temperature equal to or higher than the melting point of the polyamide resin composition, and the volume of the fibrous zonotolite is reduced. Specific energy Esp during melt-kneading of polyamide resin composition containing φ in fraction
The ratio Esp (φ) / Esp (0) between (φ) and the specific energy Esp (0) during melt-kneading of the polyamide resin alone is given by the following equation (1).

A <Esp (φ) / Esp (0) ≦ B (1) (where A = 1 + 1.028φ / (1-3.058φ), B = 1 +
3.391φ / (1-2.921φ), φ represents the volume fraction of fibrous zonotolite in the polyamide resin composition, and 0 <φ ≦ 0.3
It is 10. 1), that is, a fiber excellent in mechanical properties, in which the dispersibility of the fibrous zonotolite is good and the aspect ratio can be controlled in the range of 7 to 20 by melt-kneading in the range of the hatched portion in FIG. Zonotorite reinforced polyamide resin composition can be obtained with good reproducibility.

The specific energy Esp is represented by a value obtained by dividing the shear deformation energy per unit volume by the material density, and is the energy per unit weight of the material required for melt-kneading.
One of the features of the present invention is that by melt-kneading at a specific energy, the dispersibility of the fibrous zonotolite in the obtained polyamide resin composition is good, and the aspect ratio can be controlled to a specific range. It is.

When Esp (φ) / Esp (0) is larger than B, the dispersibility tends to deteriorate. On the other hand, Esp (φ) / Esp
When (0) is A or less, the fibrous zonotolite tends to be cut, the aspect ratio becomes too small, and the effect of improving the mechanical strength becomes insufficient.

Usually, when the polyamide resin and the fibrous zonotolite are melt-kneaded under conditions that improve the dispersibility, the fibrous zonotolite aggregates are decomposed or cut, and the aspect ratio is often smaller than 7. Even in the case of melt-kneading in the specific energy range of the present invention, decomposition or cutting of aggregates occurs. However, by setting the volume content of the fibrous zonotolite and the specific energy during melt-kneading within the range of the present invention, the average fiber diameter and the average fiber length can be controlled to a specific size, and the aspect ratio ranges from 7 to 20. Become.

Examples of the kneading machine that can be used for producing the fibrous zonotolite-reinforced polyamide resin composition of the present invention include extruders such as a single screw extruder and a twin screw extruder, a Banbury mixer, a kneader, a continuous mixer, and the like. There are known kneading devices such as mixing rolls. The polyamide resin composition of the present invention is generally obtained in the form of pellets using these kneaders. Among these kneaders, a twin-screw extruder in which the specific energy can be easily controlled and which has a good kneading effect and workability can be most preferably used.

The temperature at the time of melt-kneading differs depending on kneading factors such as the kind of polyamide resin and specific energy, but usually a temperature range that is higher by 5 to 80 ° C. than the melting point of the polyamide resin to be used is preferably used.

The fibrous zonotolite-reinforced polyamide resin composition of the present invention can be obtained by a known molding method such as injection molding, extrusion molding, compression molding, hollow molding, etc., for automobile parts, electric / electronic parts, machine parts, building materials, etc. Can be used for molded products.

[0034]

The present invention will be described more specifically with reference to the following Examples and Comparative Examples. The methods for evaluating the physical properties of molded articles obtained from the polyamide resin compositions shown in the examples and comparative examples are described below.

(1) Specific energy Esp The Esp in the twin-screw extruder is a value obtained by the following formula: Esp = (kneading torque) × (screw rotation speed) / (extrusion speed). The kneading torque at the time of melt-kneading the fibrous zonotolite-reinforced polyamide resin composition or the polyamide resin alone is a value measured using a torque meter.

(2) Evaluation of fibrous zonotolite dispersibility in resin composition The cut surface of the pellet obtained by kneading was polished, and the polished surface was observed by an optical microscope to evaluate.

(3) Average fiber diameter d, average fiber length 1 and aspect ratio 1 / d of fibrous zonotolite in the resin composition
Measurement of Ultrathin sections were cut out from the pellets obtained by melt-kneading and determined by image analysis from a transmission electron microscope photograph taken as a sample.

(4) Tensile properties Using the pellets obtained by melt-kneading, AS
A test piece was prepared according to TM D638, and the tensile strength and the tensile modulus were measured.

Example 1 Average fiber diameter of 0.2% treated with 0.5% by weight of a nonionic surfactant (polyoxyethylene lauryl ether)
5 μm, average fiber length 1.85 μm and aspect ratio 1
A fibrous zonotolite of 0.1 (manufactured by Ube Materials Co., Ltd., trade name: Zonoheidi) has a volume fraction of 0.101 and a polyamide resin (Nylon 6, manufactured by Ube Industries, Ltd., trade name: UBE nylon 1013B) has a volume fraction of 0. .899 with a 30 mm deep groove meshing co-rotating twin-screw extruder (manufactured by Ikegai Iron Works Co., Ltd.
(PCM30 type), melt kneading at a barrel temperature of 260 ° C., a screw rotation speed of 200 rpm, and an extrusion speed of 4.2 kg / h. The kneading torque at this time was 21.0 N · m, and the kneading torque of the nylon resin alone containing no fibrous zonotolite was 15.1 N · m, and Esp (φ) / Esp
(0) was 1.25. Table 1 shows the evaluation results of the obtained melt-kneaded product. Further, a test piece was prepared from the pellet of the melt-kneaded product by injection molding at a nozzle temperature of 240 ° C. and a mold temperature of 80 ° C., and the tensile properties were measured. Table 1 shows the measurement results.

Comparative Example 1 Example 1 was repeated except that the screw speed was changed to 50 rpm.
Was performed in the same manner as described above. The kneading torque at this time is 19.3 N
m, and Esp (φ) / Esp (0) was 1.71. Many agglomerates were observed in the obtained pellets, the dispersibility of the fibrous zonotolite was poor, and the average fiber length and average fiber diameter could not be measured accurately. Test pieces were prepared in the same manner as in Example 1, and the measured tensile properties are shown in Table 1.

Comparative Example 2 The same operation as in Example 1 was carried out except that the screw rotation speed was changed to 400 rpm. The kneading torque at this time is 23.5N
M, and Esp (φ) / Esp (0) was 1.01. Table 1 shows the evaluation results of the obtained pellets and test pieces prepared in the same manner as in Example 1 and the measured tensile properties.

Example 2 Example 2 was carried out in the same manner as in Example 1 except that the screw rotation speed was changed to 100 rpm. The kneading torque at this time is 22.3N
M, the kneading torque of the nylon resin alone containing no fibrous zonotolite is 0.037 N · m,
(Φ) / Esp (0) was 1.52. Table 1 shows the evaluation results of the obtained pellets and test pieces prepared in the same manner as in Example 1 and the measured tensile properties.

Example 3 Example 3 was carried out in the same manner as in Example 1 except that the screw rotation speed was changed to 300 rpm. The kneading torque at this time is 21.3 N
M, and Esp (φ) / Esp (0) was 1.09. Table 1 shows the evaluation results of the obtained pellets and test pieces prepared in the same manner as in Example 1 and the measured tensile properties.

Example 4 Example 4 was carried out in the same manner as in Example 1 except that the volume fraction φ of zonotolite was changed to 0.048. The kneading torque at this time is 1
8.4 N · m, and Esp (φ) / Esp (0) is 1.1
It was 0. Table 1 shows the evaluation results of the obtained pellets and test pieces prepared in the same manner as in Example 1 and the measured tensile properties.
It was shown to.

Example 5 The same operation as in Example 1 was carried out except that the volume fraction φ of zonotolite was changed to 0.161. The kneading torque at this time is 2
5.9 N · m, and Esp (φ) / Esp (0) is 1.
55. Evaluation result of obtained pellet and Example 1
A test piece was prepared in the same manner as described above, and the measured tensile properties are shown in Table 1.

Example 6 The same operation as in Example 1 was carried out except that the volume fraction φ of zonotolite was changed to 0.230. The kneading torque at this time is 3
8.7 N · m, and Esp (φ) / Esp (0) is 2.
It was 31. Evaluation result of obtained pellet and Example 1
A test piece was prepared in the same manner as described above, and the measured tensile properties are shown in Table 1.

[0047]

[Table 1]

[0048]

According to the present invention, a fibrous zonotolite is blended with a polyamide resin at a ratio such that the volume fraction φ is 0 <φ ≦ 0.310,
By melting and kneading within the range of the specific energy ratio represented by the formula (1), the fibrous zonotolite is uniformly dispersed,
A fibrous zonotolite-reinforced polyamide resin composition having good mechanical strength and an aspect ratio in the range of 7 to 20 can be obtained with good reproducibility.

A <Esp (φ) / Esp (0) ≦ B (1) (where A = 1 + 1.028φ / (1-3.058φ), B = 1 +
3.391φ / (1-2.921φ), φ represents the volume fraction of fibrous zonotolite in the polyamide resin composition, and 0 <φ ≦ 0.3
It is 10. )

[Brief description of the drawings]

FIG. 1 is a view showing the relationship between the volume fraction φ of fibrous zonotolite and the specific energy ratio Esp (φ) / Esp (0) when melt-kneading a polyamide resin and fibrous zonotolite. The shaded area in FIG. 1 is the range in which the fibrous zonotolite-reinforced nylon resin composition of the present invention is obtained.

[Explanation of symbols]

φ is the volume fraction of the fibrous zonotolite, Esp (φ) is the specific energy during melt-kneading of the polyamide resin composition containing φ in the volume fraction of the fibrous zonotolite, and Esp (0) is the melting of the polyamide resin alone. Indicates the specific energy during kneading.

Claims (4)

[Claims] 1. A melt-kneaded product of a polyamide resin and a fibrous zonotolite, wherein the volume fraction φ of the fibrous zonotolite in the melt-kneaded product is 0 <φ ≦ 0.310, and Characterized by having an aspect ratio of 7 to 20. 2. In producing a melt-kneaded product of a polyamide resin and a fibrous zonotolite, (a) 0.1 μm ≦ d <0.5 μm, (b)
1 μm ≦ l <5 μm and (c) 10 ≦ l / d <20
(However, d and l indicate the average fiber diameter and average fiber length of the fibrous zonotolite before melt-kneading, respectively), and the fibrous zonotolite is used in a volume fraction. Specific energy Esp (φ) during melt-kneading of φ-containing polyamide resin composition
Energy Esp during melt-kneading of polyamide and polyamide resin alone
The ratio Esp (φ) / Esp (0) to (0) is expressed by the following equation (1): A <Esp (φ) / Esp (0) ≦ B (1) (where A = 1 + 1.028φ / (1-3.058φ), B = 1 +
3.391φ / (1-2.921φ), φ represents the volume fraction of fibrous zonotolite in the polyamide resin composition, and 0 <φ ≦ 0.3
It is 10. 2. The method for producing a fibrous zonotolite-reinforced polyamide resin composition according to claim 1, wherein the melt kneading is carried out under the conditions satisfying (1). 3. The fibrous zonotolite reinforcement according to claim 1, wherein melt kneading is performed in a range of Esp (φ) / Esp (0) according to claim 2 using a twin screw extruder. A method for producing a polyamide resin composition. 4. An automotive component, an electric or electronic component comprising the fibrous zonotolite-reinforced polyamide resin composition according to claim 1.
Electronic parts, architectural parts and mechanical parts.