JP2015038191A - Composition and insulated wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composition capable of forming a molded article having a low dielectric constant and a high partial discharge starting voltage.SOLUTION: The composition contains a polyarylene sulfide (I) and a fluororesin (II) which is a tetrafluoroethylene/hexafluoropropylene copolymer. The average dispersed particle diameter of the fluororesin (II) in the composition is 0.1 μm or more and less than 2.5 μm.

Description

The present invention relates to a composition and an insulated wire.

Patent Document 1 discloses a material comprising a polyphenylene sulfide polymer matrix (PPS polymer matrix) produced by melt modification, and a modified (per) fluoropolymer dispersed in (poly) dispersibility in the matrix. A polyphenylene sulfide (per) fluoropolymer material is described.

Patent Document 2 is characterized by comprising a polyarylene sulfide resin, a crystalline thermoplastic fluororesin obtained by copolymerizing tetrafluoroethylene, vinylidene fluoride, and an asymmetric fluoromonomer having a specific structure. A thermoplastic resin composition is described.

Patent Document 3 describes a fluorine-containing polymer thermoplastic resin composition containing a mixture obtained by blending a fluorine-containing polymer having a functional group and a heat-resistant polyarylene sulfide resin.

Patent Document 4 describes a fluorine-containing polymer alloy containing a graft fluorine-containing polymer and a non-fluorine-containing polymer.

JP 2010-535922 gazette JP-A-8-176390 US Pat. No. 6,054,537 European Patent Publication No. 0761757

Excellent insulation, excellent heat resistance, and wear resistance are required for coating materials for wires used in automobiles and robots, and windings for coils used in motors. In recent years, the trend toward higher voltages and higher currents has accelerated, and studies have been made on compositions that can form molded articles having a low relative dielectric constant and a high partial discharge voltage.

An object of the present invention is to provide a composition capable of forming a molded article having a low relative dielectric constant and a high partial discharge starting voltage.

The inventors of the present invention have made extensive studies in order to obtain a composition that can form a molded article having a low relative dielectric constant and a high partial discharge starting voltage, and have focused on a mixture of a fluororesin and polyarylene sulfide. . Then, by setting the average dispersed particle size of the fluororesin dispersed in the polyarylene sulfide within a specific range, a composition having a low relative dielectric constant and a high partial discharge starting voltage can be obtained. As a result, the present invention has been completed.

That is, the present invention is a composition comprising polyarylene sulfide (I) and a fluororesin (II) which is a tetrafluoroethylene / hexafluoropropylene copolymer, wherein the average dispersion of the fluororesin (II) in the composition A composition having a particle size of 0.1 μm or more and less than 2.5 μm.

The fluororesin (II) preferably has 80 or more carbonyl groups per 10 ⁶ carbon atoms at the main chain terminal or side chain.

Carbonyl group is carbonate group, haloformyl group, formyl group, the following formula:
^{-R 4 -C (= O) -R} 5
(Wherein R ⁴ is a divalent organic group having 1 to 20 carbon atoms, and R ⁵ is a monovalent organic group having 1 to 20 carbon atoms), the following formula:
-O-C (= O) -R ⁶
Wherein R ⁶ is an alkyl group having 1 to 20 carbon atoms or an alkyl group having 2 to 20 carbon atoms containing an etheric oxygen atom, a carboxy group, an alkoxycarbonyl group, or a carbamoyl group. It is preferably a part of at least one organic group selected from the group consisting of a group, an acid anhydride bond, and an isocyanate group.

In the composition of the present invention, the mass ratio (I) :( II) of polyarylene sulfide (I) to fluororesin (II) is preferably 98: 2 to 10:90.

The present invention is also an insulated wire comprising a core wire and a covering material made of the above composition coated around the core wire.

Since the composition of this invention has the said structure, it can form a molded article which has a low dielectric constant and a high partial discharge start voltage.

The composition of the present invention comprises a fluororesin (II) which is polyarylene sulfide (I) (hereinafter also referred to as “PAS (I)”) and a tetrafluoroethylene (TFE) / hexafluoropropylene (HFP) copolymer (FEP). ) (Hereinafter also referred to as “fluororesin (II)”).

The fluororesin (II) preferably has a relative dielectric constant of less than 3.0. By forming from a composition containing a fluororesin having a relative dielectric constant of less than 3.0, a composition having a lower relative dielectric constant can be obtained. More preferably, it is 2.8 or less. Although a minimum is not specifically limited, For example, it is 2.0.
The relative dielectric constant of the fluororesin (II) is a value obtained by measurement at 25 ° C. and a measurement frequency of 10 kHz. The relative dielectric constant can be measured with an LCR meter using, for example, a measurement sample obtained by depositing aluminum on both surfaces of a film in a vacuum.

The fluororesin (II) is a copolymer of TFE and HFP. By using the fluororesin (II), the fluororesin (II) is efficiently dispersed with respect to PAS (I), the composition of the present invention exhibits more excellent mechanical properties, and is excellent in insulation properties and low. The dielectric constant is shown. Moreover, when the composition of this invention is used for the coating | covering material in an insulated wire, adhesion | attachment with a coating | covering material and a core wire will become stronger.

The fluororesin (II) preferably has a carbonyl group (—C (═O) —) at the main chain terminal or side chain. Conventionally, it has been difficult to disperse a fluororesin in polyarylene sulfide (I) due to low compatibility with each other. When the present inventors diligently studied about dispersing the fluororesin in the polyarylene sulfide (I), by using the fluororesin (II) having a specific functional group, the polyarylene sulfide (I) It has been found that an alloyed composition can be obtained by finely dispersing the fluororesin (II).
Since the composition of the present invention has a carbonyl group at the end of the main chain or a side chain, the fluororesin (II) can be finely dispersed in PAS (I), and the average dispersed particles of the fluororesin (II) The diameter can be 0.1 μm or more and less than 2.5 μm.
In the present invention, the carbonyl group may be part of a functional group having —C (═O) —.

As the functional group having a carbonyl group, for example,
Carbonate group [—O—C (═O) —OR ³ (wherein R ³ is an alkyl group having 1 to 20 carbon atoms or an alkyl group having 2 to 20 carbon atoms including an etheric oxygen atom) ],
A haloformyl group [—C (═O) X ¹ , X ¹ is a halogen atom],
Formyl group [—C (═O) H],
Formula: —R ⁴ —C (═O) —R ⁵ (wherein R ⁴ is a divalent organic group having 1 to 20 carbon atoms, and R ⁵ is a monovalent group having 1 to 20 carbon atoms. An organic group of
Formula: —O—C (═O) —R ⁶ (wherein R ⁶ is an alkyl group having 1 to 20 carbon atoms or an alkyl group having 2 to 20 carbon atoms including an etheric oxygen atom) A group represented by
A carboxy group [—C (═O) OH],
An alkoxycarbonyl group [—C (═O) OR ⁷ (wherein R ⁷ is a monovalent organic group having 1 to 20 carbon atoms)],
Carbamoyl group [—C (═O) NR ⁸ R ⁹ (wherein R ⁸ and R ⁹ may be the same or different and each represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms) )],
Acid anhydride bond [—C (═O) —O—C (═O) —],
An isocyanate group [—N═C═O],
Etc. can be mentioned as preferred functional groups.

Specific examples of R ³ include a methyl group, an ethyl group, a propyl group, an isopropyl group, and a butyl group. Specific examples of R ⁴ include a methylene group, —CF ₂ — group, —C ₆ H ₄ — group, and specific examples of R ⁵ include a methyl group, an ethyl group, a propyl group, an isopropyl group, Examples thereof include a butyl group. Specific examples of R ⁷ include methyl group, ethyl group, propyl group, isopropyl group, butyl group and the like. Specific examples of R ⁸ and R ⁹ include a hydrogen atom, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a phenyl group.

Among these, from the viewpoint of ease of introduction into the fluororesin (II) and reactivity with PAS (I), the carbonyl group is a carbonate group, a haloformyl group, a formyl group, the following formula:
^{-R 4 -C (= O) -R} 5
(Wherein R ⁴ is a divalent organic group having 1 to 20 carbon atoms, and R ⁵ is a monovalent organic group having 1 to 20 carbon atoms), the following formula:
-O-C (= O) -R ⁶
Wherein R ⁶ is an alkyl group having 1 to 20 carbon atoms or an alkyl group having 2 to 20 carbon atoms containing an etheric oxygen atom, a carboxy group, an alkoxycarbonyl group, or a carbamoyl group. It is preferably a part of at least one organic group selected from the group consisting of a group, an acid anhydride bond, and an isocyanate group.

The fluororesin (II) preferably has 80 or more carbonyl groups with respect to 1 × 10 ⁶ carbon atoms. More preferably, it is 100-5000 pieces, More preferably, it is 200-3000 pieces, Especially preferably, it is 300-1000 pieces. The number of carbonyl groups is also preferably 500 or more per 1 × 10 ⁶ carbon atoms.
When the number of carbonyl groups is within the above range, a composition capable of forming a molded article having a high partial discharge starting voltage is obtained. Moreover, when the composition of this invention is used for the coating | covering material in an insulated wire, adhesion | attachment with a coating | covering material and a core wire will become stronger.
The number of carbonyl groups is calculated from the functional group amount (number of functional groups containing a carbonyl group) determined from the absorbance of the carbonyl group by an infrared spectrometer (IR spectrometer).
More specifically, a white powder of fluororesin (II) or a cut piece of a melt-extruded pellet of fluororesin (II) is compression-molded at room temperature to prepare a film having a thickness of 50 to 200 μm. The absorbance of the peak derived from the functional group containing the carbonyl group was measured by external absorption spectrum analysis, and the functional group containing a carbonyl group per 10 ⁶ main chain carbon atoms of the polymer forming the fluororesin (II) by the following formula The number N of groups is calculated.
N = 500 AW / εdf
A: Absorbance of peak derived from functional group containing carbonyl group ε: Molar absorbance coefficient of peak derived from functional group containing carbonyl group W: Average molecular weight d of monomer calculated from composition of fluororesin (II) : Film density (g / cm ³ )
f: Film thickness (mm)

The fluororesin (II) preferably has 80 mol% or more of polymerized units based on TFE with respect to a total of 100 mol% of polymerized units based on TFE and polymerized units based on HFP. More preferably, it is 85 mol% or more, More preferably, it is 87 mol% or more, Especially preferably, it is 90 mol% or more, Most preferably, it is 93 mol% or more. Further, the polymerized unit based on TFE is preferably 99 mol% or less, more preferably 97 mol% or less, more preferably 100 mol% based on the total of the polymerized units based on TFE and the polymerized units based on HFP. Preferably it is 95 mol% or less.
The fluororesin (II) may have a polymer unit based on a monomer copolymerizable with TFE and HFP, and the polymer unit based on a monomer copolymerizable with TFE and HFP is fluorine The content is preferably 0 to 25 mol%, more preferably 8 to 20 mol%, based on 100 mol% of all polymerized units constituting the resin (II). Moreover, 0.1-5 mol% may be sufficient as the polymer unit based on the monomer copolymerizable with TFE and HFP.
The monomer copolymerizable with TFE and HFP is preferably a perfluoromonomer, for example, a perfluoroalkyl vinyl ether monomer. Examples of perfluoroalkyl vinyl ethers include perfluoro (methyl vinyl ether), perfluoro (ethyl vinyl ether), and perfluoro (propyl vinyl ether).

The fluororesin (II) preferably has a melt flow rate (MFR) measured at 372 ° C. under a load of 5000 g of 0.1 to 100 g / 10 minutes, preferably 0.1 to 40 g / 10 minutes. It is more preferable. When the MFR is in the above range, the processing characteristics of the composition of the present invention are improved. Moreover, when the composition of this invention is used for the coating | covering material in an insulated wire, adhesion | attachment with a coating | covering material and a core wire will become stronger.
The more preferable lower limit of MFR is 12 g / 10 minutes, and the particularly preferable lower limit is 15 g / 10 minutes. Since the processing characteristics are further improved, the more preferable upper limit of MFR is 38 g / 10 minutes, and the particularly preferable upper limit is 30 g / 10 minutes.
The MFR of the fluororesin (II) is measured using a melt indexer based on ASTM D 3307-01.

The melting point of the fluororesin (II) is not particularly limited. However, since it is preferable that the fluororesin (II) is already melted at a temperature at which the PAS (I) used in molding is melted, the PAS (I It is preferable that the temperature be equal to or lower than the melting point. For example, the melting point of the fluororesin (II) is preferably 230 to 350 ° C., and more preferably 250 to 340 ° C., more preferably 265 to 320 ° C., since heat resistance, wear resistance, and moldability are more excellent. Is more preferable. The melting point of the fluororesin (II) is determined as a temperature corresponding to the maximum value in the heat of fusion curve when the temperature is raised at a rate of 10 ° C./min using a differential scanning calorimetry (DSC) apparatus.

The composition of the present invention comprises PAS (I). By including the PAS (I), the resulting molded article has a high continuous use temperature and excellent heat resistance. In addition, wear resistance and moldability are excellent.

Examples of PAS (I) include the following formula:
-(Ar-S)-
(Wherein Ar represents an arylene group and S represents sulfur), and the content of the repeating unit in the resin is preferably 70 mol% or more.
Arylene groups include p-phenylene, m-phenylene, o-phenylene, alkyl-substituted phenylene, phenyl-substituted phenylene, halogen-substituted phenylene, amino-substituted phenylene, amide-substituted phenylene, p, p'-diphenylenesulfone, p, p '. -Biphenylene, p, p'-biphenylene ether, etc. can be mentioned.
Polyarylene sulfide (I) can be broadly classified into resins having a crosslinked or branched structure (crosslinked type) and resins having substantially no crosslinked or branched structure (linear type). Either a crosslinked type or a linear type can be used without any problem.
As PAS (I), for example, polyphenylene sulfide is preferably exemplified.

PAS (I) preferably has a relative dielectric constant of 3.0 to 4.0. By using PAS (I) having a relative dielectric constant of 3.0 to 4.0, a composition having a low relative dielectric constant can be formed. Furthermore, the heat resistance and wear resistance of the composition are also excellent. The relative dielectric constant of PAS (I) is more preferably 3.8 or less, and still more preferably 3.6 or less.
The relative dielectric constant of PAS (I) is a value obtained by measurement at 25 ° C. and a measurement frequency of 10 kHz. The relative dielectric constant can be measured with an LCR meter using, for example, a measurement sample obtained by depositing aluminum on both surfaces of a film in a vacuum.

PAS (I) preferably has a glass transition temperature of 70 ° C. or higher. More preferably, it is 80 degreeC or more, More preferably, it is 90 degreeC or more. When the glass transition temperature is in the above range, the heat resistance of the composition can be improved. Further, the glass transition temperature of PAS (I) is preferably 300 ° C. or lower, and more preferably 250 ° C. or lower. The glass transition temperature is measured by a differential scanning calorimetry (DSC) apparatus.

PAS (I) preferably has a melting point of 180 ° C. or higher. More preferably, it is 190 ° C. or higher. When the melting point is within the above range, the heat resistance of the composition can be improved. Further, the melting point of PAS (I) is preferably 380 ° C. or lower, and more preferably 350 ° C. or lower. The melting point is measured by a differential scanning calorimetry (DSC) apparatus.

In the composition of the present invention, the average dispersed particle size of the fluororesin (II) is 0.1 μm or more and less than 2.5 μm. When the average dispersed particle size is in the above range, the composition of the present invention is a composition that can form a molded article having a low relative dielectric constant and a high partial discharge starting voltage.
Furthermore, since the composition which can form a uniform thin film molded object is obtained, the said average dispersed particle diameter is preferable 2.0 micrometers or less, and 1.0 micrometer or less is more preferable. The lower limit of the average dispersed particle size may be, for example, 0.5 μm.

The average dispersed particle size is obtained by observing a cross section of a section cut out from a strand of the composition of the present invention with a confocal laser microscope and binarizing the obtained image with an optical analyzer. Can do.

In the composition of the present invention, the mass ratio (I) :( II) of PAS (I) to fluororesin (II) is preferably 98: 2 to 10:90. By setting to the above range, the composition has excellent insulating properties and heat resistance, and exhibits a low relative dielectric constant. Moreover, when the composition of this invention is used for the coating | covering material in an insulated wire, adhesion | attachment with a coating | covering material and a core wire will become stronger.
If the content of the fluororesin (II) exceeds 90 by mass ratio with PAS (I), the partial discharge starting voltage of the molded product obtained from the composition tends to be low, and if it is less than 2, the relative dielectric constant The rate may increase. A more preferable range of the mass ratio (I) :( II) is 90:10 to 40:60. Since the partial discharge starting voltage of the molded product obtained from the composition can be increased and the relative dielectric constant can be decreased, a more preferable range of the mass ratio (I) :( II) is 70:30 to 40:60. There is an even more preferred range of 60:40 to 40:60.
Further, when the content of the fluororesin (II) is less than that of PAS (I), the matrix of the composition tends to be PAS (I), and the content of the fluororesin (II) is PAS (I ), The composition matrix tends to be fluororesin (II).

In the composition of the present invention, the total of the PAS (I) and the fluororesin (II) is preferably 90% by mass or more, more preferably 95% by mass or more of the entire resin component, and the resin component is More preferably, it consists essentially of the PAS (I) and the fluororesin (II).

Although the composition of this invention contains PAS (I) and fluororesin (II), it may contain the other component as needed. Although it does not specifically limit as said other component, For example, a titanium oxide, a silica, an alumina, barium sulfate, a calcium carbonate, aluminum hydroxide, a potassium titanate, a magnesium oxide, a calcium oxide, clay, a talc etc. are mentioned. The insulating layer (B) may also contain a filler, an adhesion promoter, an antioxidant, a lubricant, a processing aid, a colorant, and the like.

The production of the composition of the present invention is carried out by using a mixing machine such as a compounding mill, a Banbury mixer, a pressure kneader, an extruder or the like that is usually used for mixing a resin composition such as a molding composition. It can be performed depending on conditions.
Since the average dispersed particle size of the fluororesin (II) can be reduced, the mixer is preferably a twin screw extruder, and the screw configuration of the twin screw extruder is preferably L / D = 35 or more, more preferably L / D = 40 or more, particularly preferably L / D = 45 or more. L / D is the effective length of the screw (L) / screw diameter (D).
From the above, the composition of the present invention is obtained by mixing polyarylene sulfide (I) and fluororesin (II) with a twin-screw extruder having a screw configuration with an L / D of 35 or more. Preferably there is.

As a method for producing the composition of the present invention, for example, a method in which PAS (I) and fluororesin (II) are mixed in a molten state is preferable.
By sufficiently kneading PAS (I) and fluororesin (II), the composition of the present invention having a desired dispersion state can be obtained. Since the dispersion state affects the partial discharge start voltage of the molded product and the moldability (formation of coating material, formation of a thin film), so that a desired dispersion state can be obtained in the molded product obtained from the resin composition. The selection of the kneading method should be made appropriately.

The method for producing the composition of the present invention includes, for example, putting PAS (I) and fluororesin (II) into a mixer at an appropriate ratio, adding the above-mentioned other components as desired, and adding PAS (I) and fluorine. A method of producing by melting and kneading at a melting point or higher of the resin (II) is preferable.
The temperature at the time of melt kneading may be appropriately set depending on the type of PAS (I) and fluororesin (II) to be used, but is preferably 320 to 360 ° C, for example. The kneading time is usually 1 minute to 1 hour.
The other components may be added in advance to PAS (I) and fluororesin (II) and mixed, or may be added when blending PAS (I) and fluororesin (II). .

The shape of the composition of this invention is not specifically limited, For example, it can be set as various shapes, such as a sheet form; a film form; a rod form;
The composition of the present invention is particularly suitable for a sheet-like or film-like molded article because of its excellent tensile strength. Sheet-like and film-like molded articles are suitable for applications such as electric wires, conductor covers, toilet articles, and water-related articles.

The molded product obtained by molding the composition of the present invention has a low relative dielectric constant and a high partial discharge starting voltage, as well as excellent strength and water repellency, as well as heat resistance and chemical resistance. Excellent solvent resistance, strength, rigidity, low chemical permeability, dimensional stability, flame retardancy, electrical properties and durability. Therefore, it can be used for various applications that require the above characteristics.
For example, in the electrical / electronics / semiconductor field, CMP retainer ring, etching ring, silicon wafer carrier, semiconductor / liquid crystal manufacturing equipment parts such as IC chip tray, insulation film, small button battery, cable connector, aluminum electrolytic capacitor body case; In the field, thrust washers, oil filters, automatic air conditioner control unit gears, throttle body gears, ABS parts, AT seal rings, MT shift fork pads, bearings, seals, clutch rings; Cables for transportation systems, conveyor belt chains, connectors for oilfield development machinery, pump parts for hydraulic drive systems (bearings, port plates, ball joints for pistons); Check machine cabin interior parts, fuel line protective material; and food and beverage manufacturing equipment parts, medical instrument parts (sterilizing instruments, gas liquid chromatography) it can be used, for example.
Moreover, since the said molded object is excellent in intensity | strength, it is suitable also as a solar cell backsheet. It can also be used as a water-repellent film.

The composition of the present invention can form a molded article having a high partial discharge starting voltage by having the above-described configuration, and the composition exhibits a low relative dielectric constant. Can be suitably used.

The insulated wire of this invention consists of a coating | covering material which consists of a core wire and said composition coat | covered around the said core wire. By having the above-mentioned configuration, the insulated wire of the present invention has a high partial discharge starting voltage and a low dielectric constant of the coating material.
The covering material formed on the outer periphery of the core wire may be in contact with the core wire, or may be formed between the core wire and another layer, for example, another resin layer.
The covering material is preferably in contact with the core wire, and in that case, an insulated electric wire with strong adhesion between the core wire and the covering material is obtained.

Although the film thickness of a coating | covering material is not limited, For example, it can be set as 1-200 micrometers. The film thickness of the covering material can be 100 μm or less, or 75 μm or less. Further, the thickness can be reduced to 50 μm or less. It is advantageous to reduce the thickness of the coating material in terms of excellent heat dissipation performance.

The said coating | covering material can be obtained by shape | molding the said composition and coat | covering the outer periphery of a core wire.

The method for forming the covering material is not particularly limited, and various conditions can be used as conventionally known. Further, the covering material may be formed directly on the core wire, or may be formed through another layer, for example, another resin layer.

The coating material can be formed by melt-extrusion of the above composition on the surface of the core wire or the surface of the resin layer of the core wire on which another resin layer has been formed in advance, or by pre-melting the resin composition to produce a film. Then, after slitting the film to a predetermined size, it can be formed by a method of winding the film around the surface of the core wire or the surface of the resin layer of the core wire on which another resin layer has been formed in advance. it can.

When the coating material is molded by melt extrusion, the molding temperature is usually preferably a temperature equal to or higher than the melting point of the PAS (I) used. The molding temperature is preferably a temperature lower than the lower one of the decomposition temperature of the fluororesin (II) and the decomposition temperature of the PAS (I). Such a molding temperature may be, for example, 250 to 400 ° C. The molding temperature is preferably 280 to 400 ° C.

In the coated electric wire of the present invention, when the coating material is in contact with the core wire, the adhesive strength between the coating material obtained from the composition and the core wire can be 10 N / cm or more by using the above composition. . Due to the adhesive strength within the above range, it is particularly suitable for use in automobile electric wires and motor coil windings. The adhesive strength is more preferably 15 N / cm or more, and further preferably 20 N / cm or more.

The insulated wire of the present invention may be heated after forming a covering material. The heating may be performed at a temperature near the melting point of the fluororesin (II).

The material for forming the core wire is not particularly limited as long as the material has good conductivity, and examples thereof include copper, copper alloy, copper clad aluminum, aluminum, silver, gold, and galvanized iron.

The shape of the core wire is not particularly limited, and may be circular or flat. In the case of a circular conductor, the core wire may have a diameter of 0.3 to 2.5 mm.

The insulated wire of the present invention can be suitably used for wrapping wires, automotive wires, robot wires, and the like. Moreover, it can be used conveniently also as a coil winding (magnet wire), and if it uses the electric wire of this invention, it will be hard to produce the damage by winding processing. The above winding is suitable for motors, rotating electrical machines, compressors, transformers, etc., requires high voltage, high current and high thermal conductivity, requires high-density winding processing, and is downsized. -It has the characteristics that it can sufficiently withstand the use with high output motors. Moreover, it is suitable also as an electric wire for power distribution, power transmission, or communication.

Next, the present invention will be described with reference to examples, but the present invention is not limited to such examples.

<Calculation of average dispersed particle size>
A strand of the resin composition obtained by melt-kneading was fixed to a microtome (manufactured by Micro Edge Instruments) sample holder, and a section having a thickness of about 30 μm was cut out. The cross section of the obtained slice was observed using a laser microscope (manufactured by Keyence Corporation). The obtained image was binarized using an image analysis software (WinROOF v6.3, manufactured by Mitani Corporation) to determine the average dispersed particle size of the dispersed phase.

<Production of film>
Pellets of the resin composition are transferred to a T-die extruder for film molding (φ20 mm, L / D = 25, die width 150 mm, lip width 0.4 mm; Labo plast mill T die extrusion apparatus manufactured by Toyo Seiki Seisakusho). A film having a thickness of 100 μm was formed under the conditions of a cylinder temperature of 325 to 345 ° C., a die temperature of 330 ° C., and a screw rotation speed of 40 to 60 rpm.

<Measurement of relative permittivity>
A film prepared by the above-described method (thickness: 100 μm) is vacuum-deposited on both sides in a vacuum to obtain a measurement sample. The measurement sample is measured for capacitance and dielectric loss tangent at a frequency of 10 kHz using an LCR meter (ZM2353 manufactured by NF Circuit Design Block Co., Ltd.) at 25 ° C. in a dry air atmosphere. The relative dielectric constant was calculated from each obtained capacitance and the film thickness.

<Partial discharge start voltage>
The partial discharge start voltage was measured at a frequency of 100 kHz and a charge amount of 10 pC using a Soken Denki Co., Ltd. DAC-PD-3 for the twist piece.

<Number of functional groups having a carbonyl group>
A piece of white powder of fluororesin (II) or a melt-extruded pellet of fluororesin (II) is compression molded at room temperature to produce a film having a thickness of 50 to 200 μm. By infrared absorption spectrum analysis of this film, The absorbance of the peak derived from the functional group containing the carbonyl group is measured, and the number N of functional groups containing the carbonyl group per 10 ⁶ main chain carbon atoms of the polymer forming the fluororesin (II) is calculated by the following formula. To do.
N = 500 AW / εdf
A: Absorbance of peak derived from functional group containing carbonyl group ε: Molar absorbance coefficient of peak derived from functional group containing carbonyl group W: Average molecular weight d of monomer calculated from composition of fluororesin (II) : Film density (g / cm ³ )
f: Film thickness (mm)
In addition, Perkin-Elmer FTIR spectrometer 1760X (made by Perkin Elmer) was used for the infrared absorption spectrum analysis. The thickness of the film was measured with a micrometer.

In the examples and comparative examples, the following materials were used.
Polyarylene sulfide (1): Polyphenylene sulfide (Fortron (registered trademark) PPS, grade 0220A, relative dielectric constant 3.5, melting point 280 ° C., glass transition temperature 90 ° C.)
Fluororesin (1): Tetrafluoroethylene / hexafluoropropylene copolymer (composition weight ratio; tetrafluoroethylene / hexafluoropropylene / perfluoro (propyl vinyl ether) = 87.5 / 11.5 / 1.0, MFR; .. 23 g / 10 min melt viscosity; 0.55kNsm ^-2 mp 255 ° C., relative dielectric constant: 2.1, number of functional groups having a carbonyl group: 31 carboxy groups per 10 ⁶ carbon, 10 haloformyl )
Fluororesin (2): Tetrafluoroethylene / hexafluoropropylene copolymer (composition weight ratio; tetrafluoroethylene / hexafluoropropylene / perfluoro (propyl vinyl ether) = 87.5 / 11.5 / 1.0, MFR; .. 23 g / 10 min melt viscosity; 0.55kNsm ^-2 mp 255 ° C., relative dielectric constant: 2.1, number of functional groups having a carbonyl group: 707 amino carboxy groups per 10 ⁶ carbon atoms)
Fluororesin (3): Tetrafluoroethylene / perfluoro (propyl vinyl ether) copolymer (composition ratio (weight ratio); tetrafluoroethylene / perfluoro (propyl vinyl ether) = 94.5 / 5.5, MFR; 25 g / 10 min, melting point 300 ° C., the dielectric constant 2.1, the melt viscosity 0.80KNsm ^-2, number of functional groups having a carbonyl group: 28 carboxy groups per 10 ⁶ carbon atoms, a haloformyl group 23)
Fluororesin (4): Tetrafluoroethylene / hexafluoropropylene copolymer (composition weight ratio; tetrafluoroethylene / hexafluoropropylene = 89.5 / 10.5, MFR; 20 g / 10 min. Melt viscosity; 0.53 kNsm . ^-2 mp 255 ° C., relative dielectric constant: 2.1, number of functional groups having a carbonyl group: 208 amino carboxy groups per 10 ⁶ carbon atoms)

<Example 1>
Polyarylene sulfide (1) and fluororesin (2) were premixed at the ratio (parts by mass) shown in Table 1, and the cylinder temperature was 310 ° C. using a twin-screw extruder (φ15 mm, L / D = 60). The resin composition pellets (and strands) were manufactured by melt-kneading under conditions of a screw rotation speed of 300 rpm.

The obtained pellets of the resin composition were melt-extruded on the conductor at a die temperature of 330 ° C. and a molding speed of 30 m / min to form an insulating coating having a thickness of 100 μm on the conductor.

<Examples 2 to 5>
Resin composition pellets (and strands) in the same manner as in Example 1 except that the ratio (parts by mass) of polyarylene sulfide (1) and fluororesin (2) or screw rotation speed was changed as shown in Table 1. Manufactured.
Next, an insulated wire was produced in the same manner as in Example 1 except that the obtained resin composition pellets were used.
Thereafter, the average dispersed particle size, relative dielectric constant, and partial discharge starting voltage were evaluated by the above methods. The results are shown in Table 1.

<Examples 6 to 7>
Example 1 except that the fluororesin (4) was used instead of the fluororesin (2), and the ratio (parts by mass) of the polyarylene sulfide (1) and the fluororesin (4) was changed as shown in Table 1. Resin composition pellets (and strands) were produced in the same manner.
Next, an insulated wire was produced in the same manner as in Example 1 except that the obtained resin composition pellets were used.
Thereafter, the average dispersed particle size, relative dielectric constant, and partial discharge starting voltage were evaluated by the above methods. The results are shown in Table 1.

<Comparative Example 1>
Using only polyarylene sulfide (1), a film and an insulated wire were produced in the same manner as in Example 1. Thereafter, the dielectric constant and the partial discharge starting voltage were evaluated by the above methods. The results are shown in Table 1.

<Comparative Examples 2-4>
Other than using fluororesin (1) instead of fluororesin (2), changing the ratio (parts by mass) of polyarylene sulfide (1) and fluororesin (1), and screw rotation speed as shown in Table 1. Produced pellets (and strands) of the resin composition in the same manner as in Example 1.
Next, the film and the insulated wire were produced by the same method as Example 1 except having used the pellet of the obtained resin composition.
Thereafter, the average dispersed particle size, relative dielectric constant, and partial discharge starting voltage were evaluated by the above methods. The results are shown in Table 1.

<Comparative Example 5>
Implemented except that the fluororesin (3) was used instead of the fluororesin (2), and the ratio (parts by mass) of the polyarylene sulfide (1) and each fluororesin (3) was changed as shown in Table 1. In the same manner as in Example 1, pellets (and strands) of the resin composition were produced.
Next, production of a film was attempted in the same manner as in Example 1 except that the obtained resin composition pellets were used, but polyphenylene sulfide and fluororesin were separated to produce a uniform film. It was not possible to measure the relative permittivity and the partial discharge start voltage.

The composition of the present invention is particularly suitably used as a covering material for insulated wires.

Claims (5)

A composition comprising polyarylene sulfide (I) and a fluororesin (II) which is a tetrafluoroethylene / hexafluoropropylene copolymer,
An average dispersed particle size of the fluororesin (II) in the composition is 0.1 μm or more and less than 2.5 μm. The composition according to claim 1, wherein the fluororesin (II) has 80 or more carbonyl groups per 10 ⁶ carbon atoms at the main chain terminal or side chain. Carbonyl group is carbonate group, haloformyl group, formyl group, the following formula:
^{-R 4 -C (= O) -R} 5
(Wherein R ⁴ is a divalent organic group having 1 to 20 carbon atoms, and R ⁵ is a monovalent organic group having 1 to 20 carbon atoms), the following formula:
-O-C (= O) -R ⁶
Wherein R ⁶ is an alkyl group having 1 to 20 carbon atoms or an alkyl group having 2 to 20 carbon atoms containing an etheric oxygen atom, a carboxy group, an alkoxycarbonyl group, or a carbamoyl group. The composition according to claim 1 or 2, which is a part of at least one organic group selected from the group consisting of a group, an acid anhydride bond, and an isocyanate group. The composition according to claim 1, 2 or 3, wherein the mass ratio (I) :( II) of the polyarylene sulfide (I) and the fluororesin (II) is 98: 2 to 10:90. Core wire, and
A coating material comprising the composition according to claim 1, 2, 3, or 4 coated around the core wire,
An insulated wire comprising: