JPH11302539A - Resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition excellent in various characteristics such as heat resistance, melt moldability, tenacity, light weight, etc., and molded products thereof. SOLUTION: This resin composition comprises compounding 50-2,000 pts.wt. of powdery ferrite with 100 pts.wt. of a polyamide which consists of a carboxylic acid unit containing 60-100 mole% of terephthalic acid unit and a diamine unit containing 60-100 mole% of a 6-18C aliphatic diamine unit. The molded products comprise the resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition having excellent properties such as heat resistance, melt moldability, toughness and light weight. A molded article made of the resin composition is useful as a magnetic material.

[0002]

2. Description of the Related Art A resin composition in which a magnetic powder is blended with a thermoplastic resin is excellent in toughness, light weight, melt moldability, etc., and is used in various fields including the electronics field such as magnet rolls, transformers, motors, and speakers. Used for applications. For example, a resin composition in which a magnetic powder is blended with an aliphatic polyamide (see JP-A-6-287445) or a resin composition in which a ferrite powder is blended with a polyphenylene sulfide resin having a different melt viscosity (see JP-A-6-350284) Gazettes) are known.

[0003]

The above-mentioned JP-A-6-28
As described in JP-A-7445, a resin composition in which a magnetic powder is blended with an aliphatic polyamide is relatively excellent in melt moldability, mechanical strength, and the like, and thus is used as a magnetic material such as a plastic magnet. Although used, in recent years, higher performance has been demanded for magnetic materials, and materials having more excellent properties such as heat resistance, melt moldability, toughness, and strength have been strongly desired. Further, polyphenylene sulfide resin has poor melt moldability, and has a disadvantage that the resin is hard and brittle. Therefore, as described in JP-A-6-350284, ferrite powder is added to polyphenylene sulfide resin. For example, when a chip-type coil element is externally molded using the compounded resin composition, cracks may occur in the resin due to thermal stress generated between the ferrite core and the resin inside.

An object of the present invention is to provide a resin composition having excellent properties such as heat resistance, melt moldability, toughness and light weight, and a molded article comprising the resin composition.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, a polyamide containing terephthalic acid units and aliphatic diamine units having 6 to 18 carbon atoms as main components has been obtained. By compounding ferrite powder,
A resin composition having excellent properties such as heat resistance, melt moldability, toughness, and light weight was obtained, and a molded article made of the resin composition was found to be useful as a magnetic material. Completed the invention.

That is, the present invention provides a dicarboxylic acid unit containing 60 to 100 mol% of a terephthalic acid unit and a 60 to 100 mol% of an aliphatic diamine unit having 6 to 18 carbon atoms.
The present invention relates to a resin composition comprising 50 to 2,000 parts by weight of a ferrite powder with respect to 100 parts by weight of a polyamide comprising a diamine unit. Further, the present invention relates to a molded article comprising the resin composition.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The polyamide used in the present invention contains 60 to 10 terephthalic acid units as dicarboxylic acid units.
Must contain 0 mol%, 75-100 mol%
It is preferably contained, more preferably 90 to 100 mol%. When the content of the terephthalic acid unit is less than 60 mol%, various properties such as heat resistance and chemical resistance of the obtained resin composition are reduced.

The dicarboxylic acid units other than the terephthalic acid unit include malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid Aliphatic dicarboxylic acids such as 3,3,3-diethylsuccinic acid, azelaic acid, sebacic acid and suberic acid; 1,3
Alicyclic dicarboxylic acids such as -cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; isophthalic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid;
1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, diphenic acid, dibenzoic acid, 4,4 ′
Units derived from aromatic dicarboxylic acids such as -oxydibenzoic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, and 4,4'-biphenyldicarboxylic acid. ,
One or more of these can be used. Among these, a unit derived from an aromatic dicarboxylic acid such as isophthalic acid is preferably used. Further, a unit derived from a polycarboxylic acid such as trimellitic acid, trimesic acid, and pyromellitic acid can be used within a range where the obtained resin composition can be melt-molded.

The polyamide used in the present invention must contain 60 to 100 mol% of an aliphatic diamine unit having 6 to 18 carbon atoms as a diamine unit.
The content is preferably 00 mol%, more preferably 90 to 100 mol%. 6-18 carbon atoms
Examples of the aliphatic diamine unit include 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, and 1,11-
Linear aliphatic diamines such as undecanediamine, 1,12-dodecanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl -1,6-hexanediamine, 2-methyl-1,8-octanediamine, 5
Branched aliphatic diamines such as -methyl-1,9-nonanediamine; alicyclics such as cyclohexanediamine, methylcyclohexanediamine, isophoronediamine, bis (4-aminocyclohexyl) methane, norbornanedimethylamine and tricyclodecanedimethylamine; Examples include units derived from diamines, and one or more of these units can be used. Among these, 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,11-undecane, because various properties of the obtained resin composition are excellent. Units derived from diamine, 1,12-dodecanediamine, 2-methyl-1,8-octanediamine are preferred. Furthermore, it is composed of 1,9-nonanediamine unit and 2-methyl-1,8-octanediamine unit, and 1,9-nonanediamine unit:
The molar ratio of 2-methyl-1,8-octanediamine units is preferably from 100: 0 to 10:90, and 99: 1.
The ratio is more preferably from 10:90 to 95: 5-2.
More preferably, it is 0:80. As other diamine units other than the aliphatic diamine unit having 6 to 18 carbon atoms,
For example, a unit derived from an aromatic diamine such as p-phenylenediamine, m-phenylenediamine, xylenediamine, 4,4′-diaminodiphenylsulfone, and 4,4′-diaminodiphenylether can be exemplified. One or more kinds can be used.

When a polyamide is polymerized from the above dicarboxylic acids and diamines, phosphoric acid, phosphorous acid, hypophosphorous acid, and the like are used for the purpose of increasing the rate of polycondensation and preventing the polyamide produced during the polymerization from deteriorating. Alternatively, a phosphorus-based catalyst such as a salt thereof or an ester thereof is preferably added to the reaction system. Among these, a hypophosphorous acid derivative is preferred from the viewpoint that the quality of the produced polyamide is excellent, and sodium hypophosphite is particularly preferred from the viewpoint of cost and ease of handling. The addition amount of these phosphorus-based catalysts is 0.01 to 0.01% based on the total weight of dicarboxylic acid and diamine.
It is preferably 5% by weight, more preferably 0.05 to 2% by weight, and even more preferably 0.07 to 1% by weight.

For the purpose of controlling the molecular weight and improving the melt stability of the polyamide used in the present invention, it is preferable that the molecular terminal of the polyamide is blocked with a terminal blocking agent. The terminal capping agent is not particularly limited as long as it is a monofunctional compound having reactivity with the amino group or carboxyl group at the polyamide terminus. Acids or monoamines are preferred, and monocarboxylic acids are more preferred from the viewpoint of easy handling. In addition, acid anhydrides such as phthalic anhydride, monoisocyanates, monoacid halides, monoesters, and monoalcohols can also be used.

The monocarboxylic acid which can be used as a terminal blocking agent is not particularly limited as long as it has reactivity with an amino group. For example, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid Aliphatic monocarboxylic acids such as acids, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, and isobutylic acid; alicyclic monocarboxylic acids such as cyclohexanecarboxylic acid; benzoic acid, toluic acid, α- Naphthalene carboxylic acid, β-naphthalene carboxylic acid, methyl naphthalene carboxylic acid, aromatic monocarboxylic acids such as phenylacetic acid,
Alternatively, an arbitrary mixture thereof can be mentioned.
Among these, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, etc. And benzoic acid are particularly preferred.

The monoamine used as a terminal blocking agent is not particularly limited as long as it has reactivity with a carboxyl group. Examples thereof include methylamine, ethylamine, propylamine, butylamine, hexylamine and octylamine. Aliphatic monoamines such as decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine and dibutylamine; cycloaliphatic monoamines such as cyclohexylamine and dicyclohexylamine; aniline, toluidine, diphenylamine,
An aromatic monoamine such as naphthylamine, or an arbitrary mixture thereof can be mentioned. Of these,
From the viewpoints of reactivity, boiling point, stability of the sealed terminal and price, butylamine, hexylamine, octylamine,
Decylamine, stearylamine, cyclohexylamine, aniline are particularly preferred.

The amount of the terminal blocking agent that can be used in producing the polyamide varies depending on the reactivity of the terminal blocking agent used, the boiling point, the reaction apparatus, the reaction conditions, and the like. Can be used in the range of 0.1 to 15 mol% based on the total number of moles of the above.

The polyamide used in the present invention can be produced by using any known method for producing a crystalline polyamide. For example, a solution polymerization method or an interfacial polymerization method using acid chloride and diamine as raw materials; a melt polymerization method using dicarboxylic acid and diamine as raw materials;
It can be produced by a method such as solid phase polymerization. Hereinafter, an example of a method for producing a polyamide will be described.

The end-capping agent and, if necessary, a catalyst are first added to the diamine and the dicarboxylic acid in a lump to prepare a nylon salt, and once at a temperature of 200 to 250 ° C. in concentrated sulfuric acid at 30 ° C. The intrinsic viscosity [η] is 0.
A polyamide can be easily obtained by using a prepolymer of 15 to 0.25 dl / g and further performing solid phase polymerization or performing polymerization using a melt extruder. When the intrinsic viscosity of the prepolymer is in the range of 0.15 to 0.25 dl / g, a shift in the molar balance between carboxyl groups and amino groups and a decrease in the polymerization rate in the post-polymerization stage are small, and the molecular weight distribution is small. And a polyamide excellent in various performances and moldability can be obtained. When the final stage of the polymerization is carried out by solid phase polymerization, it is preferable to carry out under reduced pressure or under an inert gas flow. It is preferable because coloring and gelation can be effectively suppressed. When the final stage of the polymerization is carried out by a melt extruder, the polymerization temperature is 37
When the temperature is 0 ° C. or lower, the polyamide is hardly decomposed, and a polyamide without deterioration is obtained.

The intrinsic viscosity [η] of the polyamide used in the present invention measured at 30 ° C. in concentrated sulfuric acid is 0.4 to 3.0 d.
1 / g, more preferably 0.6 to 2.0 dl / g, even more preferably 0.8 to 1.8 dl / g. It is preferable to use a polyamide having an intrinsic viscosity [η] in this range, since a resin composition having more excellent mechanical performance and moldability can be obtained.

The ferrite powder used in the present invention may be any ferrite powder commonly used in magnetic resin compositions, such as Mn-Zn ferrite powder, Ni-Zn ferrite powder, Mn-Mg Ferrite powder, strontium ferrite powder, barium ferrite powder, and the like.
More than one species can be used. The average particle size of the ferrite powder used in the present invention is preferably 1 mm or less, and more preferably 0.6 mm or less.

The mixing ratio of the polyamide and the ferrite powder used in the present invention is such that the ferrite powder is 50 to 2000 parts by weight with respect to 100 parts by weight of the polyamide, and 100 to 15 parts by weight.
It is preferably 00 parts by weight. When the compounding amount of the ferrite powder is less than 50 parts by weight based on 100 parts by weight of the polyamide, the magnetic properties of the obtained resin composition deteriorate. On the other hand, when the amount of the ferrite powder exceeds 2,000 parts by weight with respect to 100 parts by weight of the polyamide, the resulting resin composition has poor melt fluidity and poor melt moldability.

The resin composition of the present invention may further comprise a thermoplastic resin such as polyolefin, polyphenylene ether, liquid crystal polymer, polyphenylene sulfide, etc .; Various fillers such as glass fibers, carbon fibers, inorganic powdery fillers, organic powdery fillers and the like can be blended as needed within a range not to impair the effects of the present invention.

The resin composition of the present invention can be obtained by, for example, mixing polyamide and ferrite powder with a Henschel mixer or the like and then melt-kneading the mixture with a single-screw extruder or a twin-screw extruder. Furthermore, molded articles of various shapes can be easily produced by, for example, injection molding, blow molding, extrusion molding, compression molding, and vacuum molding of the resin composition.

The molded article made of the resin composition of the present invention is, for example, a plastic magnet constituting a magnet roll, a transformer, a motor, a speaker, etc .; an electromagnetic wave shielding material constituting a noise filter, a deflection yoke, a magnetic needle core, an inductance element, etc. It can be used as a magnetic material for various purposes such as the electronics field.

[0023]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited by these examples. The penetration test, the outgassing test at the time of melting, and the solder heat resistance test in the examples were measured by the following methods.

[Penetration test] 40 × 100 × obtained by injection molding at a cylinder temperature of 330 ° C. and a mold temperature of 150 ° C.
Using 10 injection-molded pieces of 1 mm, at the center of the molded piece, when a drill having a diameter of 2 mm was rotated at 500 rpm and penetrated at a speed of 5 cm / min. Was visually observed, and the number of cracked molded articles was evaluated. This test was performed on the molded pieces immediately after molding and on the molded pieces left in a hot-air dryer at 150 ° C. for 60 hours.

[Melting Outgas Test] After melt-kneading polyamide and ferrite powder with a twin-screw extruder, 10 g of a pelletized sample was put into a 100 cc flask.
A 1 × 1 cm copper foil was suspended from above in the space of the flask. While immersing the flask prepared in the above manner in a bath at 340 ° C. for 120 minutes while flowing nitrogen at a flow rate of 50 cc / min, the presence or absence of coloring of the copper foil was visually evaluated.
The case where no coloring was observed was evaluated as ○, the case where a part was colored was evaluated as △, and the case where the entire color was colored was evaluated as x. The less the copper foil is colored, that is, the smaller the outgassing at the time of melting, the better the melt formability.

[Solder heat resistance test] Cylinder temperature 330
40 × 1 obtained by injection molding at 150 ° C. and a mold temperature of 150 ° C.
The injection molded piece of 00 × 1 mm was placed in a solder bath at 280 ° C.
After being immersed for 1 minute at an angle of 5 degrees for a length of about 40 mm,
The deformation of the molded piece was observed. The case where the molded piece was not deformed was evaluated as ○, and the case where it was deformed was evaluated as x.

Example 1 3272.9 g (19.70 mol) of terephthalic acid, 1,9
-2690.9 g (17.00 mol) of nonanediamine, 2
-Methyl-1,8-octanediamine 474.9 g
(3.00 mol), 73.27 g (0.60 mol) of benzoic acid, 6.5 g (0.1% by weight based on the raw material) of sodium hypophosphite monohydrate and 6 liters of distilled water 2
It was placed in a 0 liter autoclave and purged with nitrogen. 2
The internal temperature was raised to 210 ° C. over time. At this time, the pressure in the autoclave was increased to 22 kg / cm ² . After continuing the reaction for 1 hour, the temperature was raised to 230 ° C.
During the time, the temperature was maintained at 230 ° C., and the reaction was carried out while gradually removing water vapor and maintaining the pressure at 22 kg / cm ² . Next, the pressure was reduced to 10 kg / cm ² over 30 minutes, and the reaction was further performed for 1 hour, so that the intrinsic viscosity [η] was 0.25 dl /
g of prepolymer was obtained. Further, it was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a size of 2 mm or less. This was subjected to solid-phase polymerization at 230 ° C. and 0.1 mmHg for 10 hours to obtain a polyamide having an intrinsic viscosity [η] of 1.35 dl / g. After dry blending 900 parts by weight of Mn—Zn ferrite powder (average particle size: 2 μm) with 100 parts by weight of this polyamide, the resin composition is melt-kneaded using a twin-screw extruder with a cylinder temperature of 330 ° C. I got something. The results of the evaluation using the obtained resin composition by the above method are shown in Table 1 below.

Example 2 Mn-Zn ferrite powder (average particle size: 2 μm)
A resin composition was obtained in accordance with the method of Example 1 except that parts by weight were used. The results of the evaluation using the obtained resin composition by the above method are shown in Table 1 below.

Example 3 Ni—Zn ferrite powder (average particle size: 150 μm) was mixed with 9
A resin composition was obtained according to the method of Example 1 except that 00 parts by weight was used. The results of the evaluation using the obtained resin composition by the above method are shown in Table 1 below.

Example 4 3165.8 1,9-nonanediamine as a diamine
A polyamide was obtained according to the method of Example 1 except that g (20.00 mol) was used. To 100 parts by weight of this polyamide, 900 parts by weight of strontium ferrite powder (average particle size: 1.3 μm) were blended according to the method of Example 1 to obtain a resin composition. The results of the evaluation using the obtained resin composition by the above method are shown in Table 1 below.

Example 5 2290.9 g (13.79 mol) of terephthalic acid, 981.8 g (5.91 mol) of isophthalic acid, 2324.2 g (20.00 mol) of 1,6-hexanediamine, 73. A polyamide was prepared according to the method of Example 1 except that 27 g (0.60 mol), 6.5 g of sodium hypophosphite monohydrate (0.1% by weight based on the raw material), and 6 L of distilled water were used. Obtained. The intrinsic viscosity of the prepolymer [η]
Was 0.22 dl / g, and the intrinsic viscosity [η] of the polyamide after the solid phase polymerization was 1.21 dl / g. Using this polyamide, a resin composition was obtained with the same composition as in Example 1. The results of the evaluation using the obtained resin composition by the above method are shown in Table 1 below.

[0032]

[Table 1]

Comparative Example 1 Nylon 6 (“1013B” manufactured by Ube Industries, Ltd.) 10
A resin composition was obtained by dry-blending 900 parts by weight of Mn-Zn ferrite powder (average particle size: 2 µm) with respect to 0 parts by weight and melt-kneading using a twin-screw extruder with a cylinder temperature of 250 ° C. . Table 2 below shows the results of evaluation using the obtained resin composition by the above method.

Comparative Example 2 900 parts by weight of M with respect to 100 parts by weight of polyphenylene sulfide (“Torelina A604” manufactured by Toray Industries, Inc.)
n-Zn ferrite powder (average particle size: 2 μm) was dry-blended and melt-kneaded using a twin-screw extruder at a cylinder temperature of 320 ° C. to obtain a resin composition. Table 2 below shows the results of evaluation using the obtained resin composition by the above method.

[0035]

[Table 2]

[0036]

The resin composition of the present invention is excellent in various properties such as heat resistance, melt moldability, toughness, light weight, and the like, and a molded article made of the resin composition includes a magnet roll, a transformer, a motor, It can be suitably used for various applications in the field of electronics as a magnetic material such as a plastic magnet constituting a speaker or the like; an electromagnetic wave shielding material constituting a noise filter, a deflection yoke, a magnetic needle core, an inductance element, or the like.

Claims (3)

[Claims] 1. A terephthalic acid unit having a content of 60 to 100 mol%
A resin obtained by blending 50 to 2,000 parts by weight of ferrite powder with respect to 100 parts by weight of a polyamide comprising a dicarboxylic acid unit to be contained and a diamine unit having 60 to 100 mol% of an aliphatic diamine unit having 6 to 18 carbon atoms. Composition. 2. 60-100 mol% of the diamine unit is
1,9-nonanediamine unit and 2-methyl-1,8
2. The composition of claim 1, wherein the molar ratio of 1,9-nonanediamine unit to 2-methyl-1,8-octanediamine unit is from 100: 0 to 10:90.
The resin composition as described in the above. 3. A molded article comprising the resin composition according to claim 1.