WO2007135749A1

WO2007135749A1 - Resin composition of high heat conduction

Info

Publication number: WO2007135749A1
Application number: PCT/JP2006/310821
Authority: WO
Inventors: Takayuki Miyashita; Satomi Nakada; Takashi Usami
Original assignee: Polyplastics Co., Ltd.
Priority date: 2006-05-24
Filing date: 2006-05-24
Publication date: 2007-11-29
Also published as: CN101448899A; CN101448899B

Abstract

A polyarylene sulfide resin material that being free from the problem of wear of screws, etc., excels in moldability and resistance to heat and humidity and exhibits a high thermal conductivity. In particular, there is provided a resin composition of high heat conduction comprising 100 parts by weight of polyarylene sulfide resin, 100 to 500 parts by weight of magnesium oxide with phosphorous coating and 0.1 to 5 parts by weight of alkoxysilane compound.

Description

Description Highly thermally conductive resin composition Technical Field

The present invention relates to a highly heat conductive resin composition having excellent moldability and heat and heat resistance. Background art

Polyphenylene sulfide (hereinafter may be abbreviated as PPS) Polyarylene sulfide represented by resin (hereinafter may be abbreviated as PAS) Resin has high heat resistance, mechanical properties, chemical resistance, dimensions Because of its stability and flame retardancy, it is widely used in electrical / electronic equipment parts materials, automotive equipment parts materials, chemical equipment parts materials, etc. In recent years, these parts have become lighter, thinner, and smaller, and heat radiation inside the parts has become a problem, and there has been a demand for materials with heat dissipation.

For this reason, a method has been proposed in which alumina with a specific particle size is added to PPS resin to improve moldability and thermal conductivity (JP-A 2002-146187). Although improved, the Mohs hardness of alumina is high, so there was a problem that the extruder, the screw of the molding machine, the cylinder and the molding die were severely worn and mixed with the metal during kneading and molding with the resin.

On the other hand, a method of adding thermal conductivity to graphite by blending graphite with PPS resin has been proposed (JP-A 2003-41 1 1 9), but this method has the problem of wear of screw etc. due to the filler. Although there is no electrical conductivity at the same time as thermal conductivity, it cannot be used in fields where electrical insulation is required. Therefore, as a thermal conductive filler for resin addition, magnesium oxide, which is insulating but has relatively high thermal conductivity and lower Mohs hardness than alumina, is used to improve its moisture resistance. A coated filler has been proposed (JP-A 2003-34523). However, when this filler is used, the humidity resistance at normal temperature is improved, but the humidity resistance at high temperature and high humidity (humidity heat resistance) is inferior. In tests such as a pressure-cushing force test (hereinafter sometimes abbreviated as PCT), magnesium oxide changed to magnesium hydroxide, causing problems such as resin whitening, expansion, and a significant decrease in mechanical properties. Disclosure of the invention

An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a material having high thermal conductivity that is free from problems such as screw wear and that is excellent in moldability and wet heat resistance.

As a result of intensive studies to achieve the above object, the present inventors have found that when a specific phosphorus-containing coated magnesium oxide and an alkoxysilane compound are combined with a PAS resin, there is no problem of wear such as screw and molding. As a result, the present invention has been completed.

That is, the present invention is a highly heat conductive resin composition comprising 100 to 500 parts by weight of a polyarylene sulfide resin and 100 to 500 parts by weight of a phosphorus-containing coated magnesium oxide and 0.1 to 5 parts by weight of an alkoxysilane compound. is there. Detailed Description of the Invention

Hereinafter, the present invention will be described in detail. The PAS resin used in the present invention has a repeating unit of — (Ar—S) — (wherein Ar is an arylene group), and the _c arylene group is, for example, a p-phenylene group. , M-phenylene group, _Phenylene group, substituted phenyl group, p, p '— diphenylsulfone group, p, p' — biphenylene group, p, p '-diphenylene ether group, p, p' — diphenylene A carbonyl group, a naphthalene group, etc. can be used. In this case, in the arylene sulfide group composed of the above-mentioned arylene group, in addition to the polymer using the same repeating unit, that is, the homopolymer, in terms of the processability of the composition, Copolymers containing heterogeneous repeat units may be preferred.

As the homopolymer, those having p-phenylene sulfide group as a repeating unit, in which p-phenylene group is used as the arylene group, are particularly preferably used. As the copolymer, two or more different combinations of the arylene sulfide groups consisting of the above-mentioned arylene groups can be used, and among them, p_phenylene sulfide groups and m-phenolic groups can be used. A combination containing a lensulfide group is particularly preferably used. In this, p- phenylene sulfide group of 70 mole ⁰ /. As mentioned above, those containing 80 mol% or more are suitable from the viewpoint of physical properties such as heat resistance, fluidity (moldability) and mechanical properties.

Further, among these PAS resins, a high molecular weight polymer having a substantially linear structure obtained by condensation polymerization from a monomer mainly composed of a bifunctional halogen aromatic compound can be particularly preferably used. In addition to the chain-structured PAS resin, a partially branched or crosslinked structure is formed by using a small amount of a monomer such as a polyhaloaromatic compound having three or more halogen substituents when polycondensation is performed. A polymer with a relatively low molecular weight is heated at a high temperature in the presence of oxygen or an oxidant to increase the melt viscosity by oxidative crosslinking or thermal crosslinking. It is also possible to use polymers with improved or mixtures thereof.

The PAS resin used in the present invention is mainly composed of the linear PAS resin (310 ° C. Shear rate ^ OOsec- ^{1 having} a viscosity of 10 to 300 Pa · s), and a part thereof (1 to 30 weight ⁰ / ₀ , preferably 2 to 25% by weight) Force A mixed system with a branched or crosslinked PAS resin having a relatively high viscosity (300 to 3000 Pa · s, preferably 500 to 2000 Pa · s) may be used. In addition, the PAS resin used in the present invention is preferably one that has been purified by removing acid by-products, hot water washing, organic solvent washing (or a combination thereof), etc. after polymerization to remove by-product impurities.

Next, the high thermal conductive resin composition of the present invention is obtained by blending phosphorus-containing coated magnesium oxide and an alkoxysilane compound with the PAS resin.

The phosphorus-containing coated magnesium oxide used in the present invention includes magnesium oxide having a coating layer made of a magnesium phosphate compound, and a covering layer made of a double oxide on the surface, and at least a part of the surface thereof. A magnesium oxide further having a coating layer made of a magnesium phosphate compound.

Here, magnesium oxide having a coating layer made of a double oxide means that at least one element of aluminum, iron, silicon, and titanium and a matrix are formed on the surface of the magnesium oxide. Includes Gnesium. Specific examples the mixed oxide, Fuorusuterai preparative (M g S i _4), spinel (A 1 ₂ M g J, magnesium Blow wells (F e ₂ M g O, magnesium titanate (M g T I_〇 ₃ Etc., preferably forsterite.

Next, a method for producing the phosphorus-containing coated magnesium oxide used in the present invention will be described.

First, a description will be given of a method for producing magnesium oxide, which is a magnesium oxide having a coating layer made of magnesium oxide and a double oxide, which is used for producing phosphorus-containing coated magnesium oxide. Magnesium oxide having the characteristics of the present invention can be produced using a known method such as an electrofusion method or a sintering method.

Next, a method for producing magnesium oxide having a coating layer made of a double oxide is to melt at a high temperature in the presence of a compound that forms a double oxide on the surface of the magnesium oxide produced by the above method. The surface is coated with a double oxide. Specifically, a compound that forms a double oxide is wet-added to the magnesium oxide powder, and then mixed and stirred, or a compound that forms a double oxide is present on the surface of the magnesium oxide. It can be produced by a method of firing at a temperature higher than the melting point of the coating material.

The compound used to form the double oxide is preferably one or more compounds selected from the group consisting of aluminum compounds, iron compounds, silicon compounds and titanium compounds. The form of the compound is not limited, but nitrates, sulfates, chlorides, oxynitrates, oxysulfates, oxychlorides, hydroxides, oxides and the like are used. Specific examples of this compound include fumed silica, aluminum nitrate, and iron nitrate.

The method for producing a phosphorus-containing coated magnesium oxide is a method in which a magnesium oxide having a coating layer made of magnesium oxide or a double oxide produced by the above method is subjected to a surface treatment with a phosphorus compound, and the surface thereof is converted into a magnesium phosphate compound. A covering layer is formed.

Phosphorus compounds used for this surface treatment include phosphoric acid, phosphate, and acidic phosphoric acid. An ester etc. can be mentioned, These may be used individually or may use 2 or more types simultaneously. Examples of the phosphate include sodium phosphate, potassium phosphate, and ammonium phosphate. Examples of the acidic phosphate ester include isopropyl acid phosphate, methenorea acid phosphate, etheno rare acid phosphate, propyl acid phosphate, and butyl acid. Examples include dophosphate, lauryl urea acid phosphate, stearino rare acid phosphate, 2-ethynolehexyl acid phosphate, and oleyl acid phosphate. Of these, isopropyl acid phosphate is preferred because a coating layer having excellent water resistance can be easily formed.

As a specific method of surface treatment of phosphorus-containing coated magnesium oxide with a phosphorus compound, a predetermined amount of phosphorus compound is added to magnesium oxide having a coating layer made of magnesium oxide or a double oxide, and stirred for 5 to 60 minutes, for example. Thereafter, it is baked at a temperature of 300 ° C. or more for 0.5 to 5 hours.

Phosphorus-containing coated magnesium oxide produced by such a method is generally available as COOLFILER 1 C F 2-10 O A (Tateho Chemical Co., Ltd.).

In the present invention, the addition amount of the phosphorus-containing coated magnesium oxide is important. If the addition amount is too small, the desired thermal conductivity does not appear, and conversely if the addition amount is too large, the moldability is deteriorated. . Therefore, the addition amount of the phosphorus-containing coated magnesium oxide is 100 to 500 parts by weight, preferably 150 to 400 parts by weight with respect to 100 parts by weight of the PAS resin. In addition, the particle size distribution of the phosphorus-containing coated magnesium oxide is also important. If the average particle size is too small, when it is kneaded with a resin, there is a problem that the viscosity is severely increased and the moldability is remarkably lowered. On the other hand, if it is too large, the thermal conductivity is improved, but the mechanical properties are degraded. Also, if the maximum particle size is too large, a single particle of filler fills the mold gate during injection molding, causing problems such as short shots. Therefore, the average particle size and to the 10~50 _{μ πι,} preferably 15~30 μ ιτι, and the maximum particle size is 300 mu m or less, preferably 150 μ πι below.

Next, the alkoxysilane compound used in the present invention is aminoalkoxysilane, vinylanoloxysilane, epoxyanoloxysilane, menolecaptoanoloxysilane. It may be at least one selected from the group consisting of lan and arylalkoxysilanes.

As an aminoalkoxysilane, a silane compound having one or more amino groups in one molecule and two or three alkoxy groups is also effective. For example, γ-aminopropyltrimethyl Xysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyljetoxysilane, Ν — (/ 3_aminoethyl) γ-aminopropyl trimethoxysilane, Ν-phenol Examples include γ-aminopropyl trimethoxysilane;

As the vinyl alkoxysilane, any silane compound having one or more vinyl groups in one molecule and having two or three alkoxy groups is effective. For example, vinyltrimethoxysilane, butyltriethoxysilane, Vinyl tris

(/ 3-methoxyethoxy) silane and the like.

As the epoxyalkoxysilane, any silane compound having one or more epoxy groups in one molecule and two or three alkoxy groups is effective, for example, γ-glycidoxypropyl trimethyl. Toxisilane, β- (3,4-epoxycyclohexyl) ethyltrimethylsilane, γ-glycidoxypropyl triethoxysilane, and the like.

As a mercaptoalkoxysilane, a silane compound having one or more mercapto groups in one molecule and having two or three alkoxy groups is also effective. For example, γ-mercaptopropyl trimethoxysilane , Γ-mercaptopropyltriethoxysilane and the like.

As the arylalkoxysilane, any silane compound having one or more aryl groups and two or three alkoxy groups in one molecule is effective. For example, γ-diarylaminopro Examples thereof include biltrimethoxysilane, γ-arylaminopropyl trimethoxysilane, and γ-arylthiopropyl trimethoxysilane.

For the purpose of the present invention, among the above alkoxysilane compounds, aminoalkoxy Sisilane is most preferred.

In the present invention, the addition amount of the alkoxysilane compound is important. If the amount of the alkoxysilane compound is small, the mechanical properties after the PCT are significantly decreased. Therefore, the addition amount of the alkoxysilane compound is 0.1-5 parts by weight, preferably 0.5-4 parts by weight with respect to 100 parts by weight of the PAS resin.

In addition, the present invention is a method for producing a highly thermally conductive resin composition. (1) A method in which all raw materials are mixed and kneaded. The effect of the present invention is exhibited by any method, such as a method of adding a coated magnesium oxide, (3) a method of adding a alkoxysilane compound to a phosphorus-containing coated magnesium oxide after the PAS resin is melted, and the like. However, since the mechanical strength is improved by the reaction between the PAS resin and the alkoxysilane compound, the (2) alkoxysilane compound is added to the PAS resin and melted so that the PAS resin and the alkoxysilane compound react more efficiently. After kneading, it is preferable to produce by a method of adding phosphorus-containing coated magnesium oxide.

In addition, the high thermal conductive resin composition of the present invention is within the object range of the present invention, and is used for improving the performance such as mechanical strength, heat resistance, dimensional stability (deformation resistance, warpage) and electrical properties. 'May be a mixture of organic fillers. For this purpose, fibrous, granular or plate-like fillers are used depending on the purpose.

Examples of the fibrous filler include inorganic fibrous materials such as glass fiber, asbestos fiber, boron fiber, and titanic acid lithium fiber. A particularly typical fibrous filler is glass fiber. High melting point organic fiber materials such as polyamide, fluorine resin, and acrylic resin can also be used.

On the other hand, the granular fillers include quartz powder, glass beads, glass powder, calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth, silicates such as wollastonite, iron oxide, titanium oxide, zinc oxide. Examples include metal oxides such as calcium carbonate, metal carbonates such as magnesium carbonate, calcium sulfate, and metal sulfates such as barium sulfate. Examples of the plate-like filler include My strength and glass flakes.

These inorganic fillers can be used alone or in combination of two or more.

In addition, known substances generally added to thermoplastic resins, that is, flame retardants, colorants such as dyes and pigments, stabilizers such as antioxidants and ultraviolet absorbers, lubricants, crystallization accelerators, crystal nucleating agents, etc. In addition, those appropriately added according to the required performance can also be used as the composition of the present invention.

Molded products obtained by injection molding, extrusion molding, blow molding, etc. using the high thermal conductive resin composition of the present invention thus obtained have high moisture and heat resistance, chemical resistance, dimensional stability, Shows flame retardancy and excellent heat dissipation. Taking advantage of this advantage, it can be suitably used for components that radiate heat generated internally, such as heat exchangers, heat sinks, and optical pickups.

Other applications include, for example, LEDs, sensors, connectors, sockets, terminal blocks, printed circuit boards, motor parts, ECU cases, and other electrical and electronic parts, lighting parts, TV parts, rice cooker parts, microwave oven parts, irons, etc. It can be used for household and office electrical product parts such as parts, copier-related parts, printer-related parts, facsimile-related parts, heaters, and air conditioner parts. Example

Next, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to these. In addition, the method of the physical-property measurement in an Example is as follows.

(1) Thermal conductivity

The thermal conductivity was measured by the hot disk method using a sample with a disk-shaped molded product with a diameter of 30 mm and a thickness of 2 mm.

(2) Liquidity

A rod-shaped product having a width of 20 mm and a thickness of 1 mm was molded under the conditions of a cylinder temperature of 340 ° C and an injection pressure of lOOMPa, and the flow distance was measured.

(3) Bending test

Using 80 x 10 x 4 mm IS standard test piece, bending strength and strength according to ISO 1 78 The bending elastic modulus was measured.

(4) Moist heat resistance

Using a standard 80 x 10 x 4 mm ISO test piece, perform a pressure cooker test for 48 hours at 121 ° C, 100% humidity and 2 atm. The test piece is subjected to bending strength according to ISO 1 78 The retention rate relative to the initial value was determined. In addition, the specimen after the pressure cooker test was confirmed by X-ray diffraction analysis for the change of magnesium oxide to magnesium hydroxide.

Examples 1-6, Comparative Examples 1-5

Using a twin-screw extruder (TEX 30 _α type, manufactured by Nippon Steel Works) with the composition and the alkoxysilane compound addition method shown in Table 1, the polyphenylene sulfide resin, the filler and the alkoxysilane compound. After kneading to form pellets, the above-mentioned test pieces were molded using an injection molding machine and subjected to various evaluations. The results are shown in Table 1.

The components used and the method of adding alkoxysilane compounds are as follows: 'Polyphenylene sulfide resin (PPS resin); Pho-Tron w 202 A manufactured by Kureha Chemical Industry Co., Ltd.

-Filler 1; Phosphorus-containing coated magnesium oxide, average particle size 27μιπ, maximum particle size 100μm (cool filler CF 2-10 OA manufactured by Tateho Chemical Co., Ltd.)

• Filler 2 (comparative product): Silica-coated magnesium oxide, average particle size 27 μm, maximum particle size 100 / xm (Categote Cf 2-100 manufactured by Tateho Chemical Co., Ltd.)

• Alkoxysilane; γ-Aminopropyltriethoxysilane

(Method of adding alkoxysilane compound)

-Method Α; After melt-kneading PPS resin and alkoxysilane, add filler with side feed

'Method B: After melt-kneading the PPS resin, add a filler containing alkoxysilane with side feed Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5

PPS resin parts by weight 100 100 100 100 100 100 100 100 100 100 100 filler 1 potato 300 300 300 300 150 400 600 300 300

Filler 2 parts by weight 300 300 alkoxysilane parts by weight 0.6 3 0.6 3 1.5 4 1 6 3 Addition method of alkoxysilane-A A B B B B A A A Moisture and heat resistance retention% 73 76 75 79 77 73 * 1 49 * 2 1 1 32

Chemical change ― No * 1 氺 2 Yes Yes Bending strength M Pa 127 145 82 121 134 102 * 1 78 * 2 93 138 Flexural modulus M Pa 20500 19700 21200 20400 1 1700 26700 * 1 21400 氺 2 21600 20200 Fluidity mm 62 49 63 5.8 135 35 * 1 65 12 4.7 42 Thermal conductivity W / m-K 1.7 1.7 1.7 1.7 0.9 2.5 * 1 1.8 * 2 1.9 1.7

* 1; Cannot be evaluated due to increased viscosity during melt kneading.

* 2; Cannot create specimen due to increased viscosity.

Claims

The scope of the claims

1. A highly thermally conductive resin composition comprising 100 to 500 parts by weight of a phosphorus-containing coated magnesium oxide and 0.1 to 5 parts by weight of an alkoxysilane compound per 100 parts by weight of a polyarylene sulfide resin.

2. The highly thermally conductive resin composition according to claim 1, wherein the phosphorus-containing coated magnesium oxide has a coating layer made of a magnesium phosphate compound.

3. The phosphorus-containing coated magnesium oxide has a coating layer made of a double oxide on the surface, and further has a coating layer made of a magnesium phosphate compound on at least a part of the surface. High thermal conductive resin composition.

4. The highly thermally conductive resin composition according to claim 3, wherein the double oxide contains one or more elements selected from the group consisting of aluminum, iron, silicon and titanium and magnesium.

5. The high thermal conductivity resin according to any one of claims 1 to 4, wherein the phosphorus-containing coated magnesium oxide has a particle size distribution with an average particle size of 10 to 50 zm and a maximum particle size of 300 / i in or less. Composition.

6. The high thermal conductive resin according to any one of claims 1 to 4, wherein the alkoxysilane compound is added to the polyarylene sulfide resin, and after melt-kneading, the phosphorus-containing coated magnesium oxide is added. A method for producing the composition.