JP2001288363A - Reinforced polyarylene sulfide resin composition having good tracking resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforced polyarylene sulfide resin composition which has improved tracking resistance without deteriorating the original physical properties, such as heat resistance, electric insulating property and low water absorbency, of the polyarylene sulfide resin. SOLUTION: This reinforced polyarylene sulfide resin composition comprising (A) 100 pts.wt. of a polyarylene sulfide resin, (B) 50 to 300 pts. wt. of magnesium hydroxide which has an average particle diameter of <=1 μm and containing particles having particle diameters of <=1 μm in an accumulated weight of >=70% in a particle size distribution, and (C) 0 to 350 pts.wt. of a fibrous filler and/or a nonfibous filler except the magnesium hydroxide, and having a ΔY satisfying the following expression (1): ΔY>b/(a+b+c)×(18/58)×90 (1) [ΔY is a thermal weight change (%) measured with a thermogravimetric analyzer in a nitrogen atmosphere, when heated from 350 deg.C to 450 deg.C at a heating speed of 10 deg.C/min; and (a), (b) and (c) are the parts by weight of the components (A), (B) and (C), respectively].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a reinforced polyarylene sulfide resin composition having good tracking resistance. The molded article made of the resin composition of the present invention is suitably used for electric / electronic parts, automobile electric parts and the like.

[0002]

2. Description of the Related Art Polyphenylene sulfide (hereinafter sometimes abbreviated as PPS)
Polyarylene sulfide represented by resin (hereinafter P
AS may be abbreviated as AS) resin has high heat resistance, mechanical properties, chemical resistance, dimensional stability, and flame retardancy. Widely used for chemical equipment parts materials. However, PAS resins have a drawback in that tracking resistance is significantly inferior to other engineering plastics such as polyamide resins. For this reason, PAS resins have excellent properties as electrical component materials such as high heat resistance, mechanical properties, dimensional stability, and flame retardancy, but they are used for applications that are exposed to relatively high voltages. The fact is that the application is restricted.

Attempts have been made to improve the tracking resistance of PAS resins. However, in systems in which magnesium hydroxide is blended with PAS resins, magnesium hydroxide decomposes when the cylinder temperature during melt-kneading is high. Therefore, there is a problem that sufficient tracking resistance cannot be obtained. JP-A-5-271542 discloses that the tracking resistance is improved by blending a polyamide resin and magnesium hydroxide with a PAS resin, but since a large amount of polyamide is used, the resulting composition The dimensional change upon water absorption is large, and the strength is significantly reduced under an aqueous solution containing an electrolyte such as calcium chloride. The tracking resistance test is a test that evaluates the likelihood of dielectric breakdown in a bad environment in the presence of moisture and electrolytes.Therefore, the application of such a composition to applications requiring high tracking resistance requires long-term reliability. Problems remain in terms.

On the other hand, Japanese Patent Application Laid-Open No. Hei 8-291253 discloses that the tracking resistance is improved by blending a polyolefin copolymer and magnesium hydroxide with a PAS resin. And a mixture of olefin-based copolymer containing glycidyl ester of α, β-unsaturated acid as a main component is PAS
Since the processing temperature of the resin is 300 ° C. or higher, the olefin-based copolymer is thermally degraded, decomposes at the time of molding and generates gas, and thus has a problem that the moldability is significantly reduced.

[0005] In view of the above situation, the present invention provides a PAS resin having the inherent toughness and mold releasability without deteriorating the inherent properties of the PAS resin such as heat resistance, electrical insulation and low water absorption. An object of the present invention is to provide a reinforced PAS resin composition having excellent tracking properties.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that magnesium hydroxide having a specific particle size distribution in PAS resin, and fibrous and / or non-fibrous By mixing resin filler and controlling the resin temperature during melt-kneading, the tracking resistance is dramatically improved, and it also has other excellent physical properties such as moldability, mechanical properties, heat resistance, etc. The present inventors have found that the following PAS resin composition can be obtained, and have completed the present invention.

That is, the present invention relates to (A) 100 parts by weight of a polyarylene sulfide resin, (B) an average particle diameter of 1 μm or less, and a cumulative weight of particle diameter of 1 μm or less as a particle size distribution is 70% or more. 50 to 300 parts by weight of magnesium hydroxide (C) A polyarylene sulfide resin composition containing 0 to 350 parts by weight of a fibrous and / or non-fibrous filler other than magnesium hydroxide, wherein the polyarylene sulfide is The present invention relates to a reinforced polyarylene sulfide resin composition in which ΔY of the resin composition satisfies the following formula (1).

ΔY> b / (a + b + c) × (18/58) × 90 (1) (Here, ΔY is measured from 350 ° C. at a rate of 10 ° C./min in a nitrogen atmosphere using a thermogravimetric analyzer. Thermogravimetric change (%) when heated to 450 ° C, where a, b, and c are components (A)
, (B), and (C). )

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the components of the present invention will be described in detail. PA as component (A) used in the present invention
The S resin is mainly composed of-(Ar-S)-(where Ar is an arylene group) as a repeating unit. Examples of the arylene group include p-phenylene group, m-phenylene group, o-phenylene group, substituted phenylene group, p, p ′
-Diphenylene sulfone group, p, p'-biphenylene group,
A p, p'-diphenylene ether group, a p, p'-diphenylenecarbonyl group, a naphthalene group and the like can be used. In this case, among the arylene sulfide groups composed of the above-mentioned arylene groups, in addition to a polymer using the same repeating unit, that is, a homopolymer, a copolymer containing a heterogeneous repeating unit from the viewpoint of processability of the composition Is sometimes preferred. As the homopolymer, one having a p-phenylene sulfide group as a repeating unit using a p-phenylene group as an arylene group is particularly preferably used. Further, as the copolymer, among the arylene sulfide groups consisting of the above-described arylene groups, two or more different combinations can be used. Among them, a combination containing a p-phenylene sulfide group and an m-phenylene sulfide group is particularly preferably used. Can be In this, p
Those containing a phenylene sulfide group in an amount of 70 mol% or more, preferably 80 mol% or more, are suitable in terms of physical properties such as heat resistance, moldability, and mechanical properties. In addition, these P
Among the AS resins, a high molecular weight polymer having a substantially linear structure obtained by condensation polymerization from a monomer mainly containing a bifunctional halogen aromatic compound can be particularly preferably used. Other than the above, when a polycondensation is carried out, a polymer having a partially branched or cross-linked structure formed by using a small amount of a monomer such as a polyhalo aromatic compound having three or more halogen substituents can be used. It is also possible to use a polymer in which a linear polymer having a low molecular weight is heated at a high temperature in the presence of oxygen or an oxidizing agent to increase the melt viscosity by oxidative crosslinking or thermal crosslinking, thereby improving moldability.

The component (A) PAS resin is mainly composed of the linear PAS (having a viscosity of 10 to 300 Pa · s at a temperature of 310 ° C. and a shear rate of 1200 sec ⁻¹ ).
30% by weight, preferably 2 to 25% by weight) has a relatively high viscosity (300 to 3000 Pa · s, preferably 500 to 2
A mixed system with a branched or crosslinked PAS resin of 000 Pa · s) is also suitable. Also, the PAS resin used in the present invention, after polymerization,
It is preferable to use acid washing, hot water washing, or organic solvent washing (or a combination thereof) to remove and purify by-product impurities and the like.

Next, as the magnesium hydroxide of the component (B) of the present invention, a highly pure magnesium hydroxide containing at least 80% by weight of an inorganic substance represented by the chemical formula Mg (OH) ₂ can be mentioned. For expression, those containing 80% by weight or more of an inorganic substance represented by Mg (OH) ₂ and having a CaO content of 5% by weight or less and a chlorine content of 1% by weight or less, more preferably
Mg (OH) ₂ of 95% by weight or more, CaO content of 1% by weight or less, chlorine content of 0.5% by weight or less, more preferably Mg
High-purity magnesium hydroxide containing 98% by weight or more of (OH) ₂ and having a CaO content of 0.1% by weight or less and a chlorine content of 0.1% by weight or less is suitable.

In the present invention, it is essential to use magnesium hydroxide having an average particle size of 1 μm or less as measured by a laser diffraction scattering method and a particle size distribution of 70% or more of the cumulative weight of the particle size of 1 μm or less. I do. Sufficient tracking resistance cannot be obtained with magnesium hydroxide having an average particle size exceeding 1 μm. Even if the average particle size is 1 μm or less, magnesium hydroxide having a particle size distribution of less than 70% with a particle size of 1 μm or less does not show a sufficient tracking resistance improving effect.

The use of the magnesium hydroxide after surface treatment with a silane coupling agent or a phosphate ester is desirable in that tracking resistance is improved while maintaining mechanical strength.

The silane coupling agent used herein includes vinyl silane compounds such as vinyl ethoxy silane, vinyl triethoxy silane, vinyl trichloro silane, γ-glycidoxy propyl trimethoxy silane, γ
-Glycidoxypropyltriethoxysilane, β-
Epoxysilane compounds such as (3,4-epoxycyclohexyl) ethylmethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ- (2
-Aminoethyl) aminopropyltrimethoxysilane,
Aminosilane compounds such as γ-aminopropyltrimethoxysilane, γ-methacryloxypropylmethylmethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, etc. Acrylic silane compounds and the like can be mentioned.

The phosphoric esters used herein include those represented by the following general formula (2).

[0016]

Embedded image

(Wherein, R is an alkyl or alkylene group having 10 to 30 carbon atoms, M is an atom of Group 1A of the periodic table or H ₄
^{+ And} n represent 1 or 2. Of the above surface treatment agents, particularly preferred in the effect of improving tracking resistance are acrylic silane compounds and phosphoric esters. The acrylic silane compound has a good melt-kneading extrudability and is a particularly preferred surface treatment agent.
The amount of the surface treating agent to be treated with respect to magnesium hydroxide is appropriately 0.1 to 10% by weight, preferably about 1 to 5% by weight, based on magnesium hydroxide.

The amount of the magnesium hydroxide (B) is 50 to 300 parts by weight, preferably 70 to 150 parts by weight, per 100 parts by weight of the PAS resin (A). If the compounding amount is less than 50 parts by weight, the effect of improving tracking resistance is insufficient, which is not preferable.If the compounding amount exceeds 300 parts by weight, adverse effects on the mechanical strength, fluidity, etc. of the resin composition become unfavorable. .

In the present invention, a fibrous and / or non-fibrous filler other than magnesium hydroxide is used as a component (C), if necessary, in order to improve strength and dimensional stability. Examples of the fibrous filler of the component (C) include glass fiber, asbestos fiber, carbon fiber, silica fiber, silica-alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, and potassium titanate fiber. And inorganic fibrous substances. Particularly typical fibrous fillers are glass fibers and carbon fibers. Non-fibrous fillers include silicates such as carbon black, silica, quartz powder, glass beads, glass powder, calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth, and wollastonite. Metal oxides such as iron oxide, titanium oxide, zinc oxide and alumina; metal carbonates such as calcium carbonate and magnesium carbonate; metal sulfates such as calcium sulfate and barium sulfate; and other silicon carbide, silicon nitride and nitride Examples include powdery and granular fillers such as boron and various metal powders, and plate-like fillers such as mica and glass flake. These fillers can be used alone or in combination of two or more.

When using these fillers, it is desirable to use a sizing agent or a surface treatment agent if necessary.
Examples of the treating agent include functional compounds such as an epoxy compound, an isocyanate compound, a silane compound and a titanate compound. These compounds may be used after being subjected to a surface treatment or a convergence treatment in advance, or may be added simultaneously with the preparation of the material.

(C) The amount of the filler is (A) PAS resin 1
The range of 0 to 350 parts by weight is selected with respect to 00 parts by weight, and from the viewpoint of the balance between melt fluidity and mechanical strength, (A)
The amount is preferably 30 to 150 parts by weight based on 100 parts by weight of the PAS resin.

Further, in the present invention, if necessary, an olefin polymer and / or an olefin copolymer can be blended as the component (D). Examples of the olefin polymer include α, such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, and 1-decene.
-Olefins, butadiene, conjugated diene compounds such as isoprene, acrylonitrile, and the like, and homopolymers obtained by polymerizing unsaturated monomers such as olefin-based copolymers, Random, block, other than the graft copolymer, the above monomers and monomers other than the above, for example, acrylic acid, methacrylic acid, ethacrylic acid and their metal salts, methyl acrylate, methyl methacrylate, methyl ethacrylate, Glycidyl acrylate,
Unsaturated organic acids and derivatives thereof such as glycidyl methacrylate, glycidyl ethacrylate, maleic acid, and maleic anhydride; vinyl esters such as vinyl acetate; vinyl silanes such as vinyl trimethyltrimethoxysilane and γ-methacryloyloxypropyl methoxysilane; vinyl ethers , Block, and graft copolymers such as Among these olefin polymers and / or olefin copolymers, ethylene / hexene copolymers,
Particularly preferred are ethylene / octene copolymers, high density polyethylene, low density polyethylene, and linear low density polyethylene.

The amount of the (D) olefin polymer and / or olefin copolymer is as follows: (A) PAS resin 100
It is 1 to 50 parts by weight, preferably 1 to 30 parts by weight based on parts by weight. If the amount is more than 50 parts by weight, the amount of deposits on the mold during molding (mold deposit) becomes extremely large, which is not preferable.

In addition, a silane compound may be added to the resin composition of the present invention in addition to the above-mentioned surface treating agent for the purpose of suppressing generation of burrs and the like, as long as the effects of the present invention are not impaired. . Such silane compounds include vinyl silane, methacryloxy silane, epoxy silane,
Various types such as aminosilane and mercaptosilane are included, for example, vinyltrichlorosilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-mercaptopropyltri Examples include, but are not limited to, methoxysilane. (A) PAS resin 10
0.1 to 3 parts by weight, preferably 0.3 to 2 parts by weight per 0 parts by weight
Parts by weight.

Further, the resin composition of the present invention may contain known substances generally added to thermoplastic resins, that is, flame retardants, coloring agents such as dyes and pigments, stabilizers such as antioxidants and ultraviolet absorbers, A lubricant, a release agent, a crystallization accelerator, a crystal nucleating agent, and the like can be appropriately added according to required performance.

In particular, there are various release agents to be added to improve the release of the molded product from the mold at the time of injection molding. For example, polyolefin wax or pentaerythritol type fatty acid ester is added. It is particularly preferred to blend a polyolefin wax as the component (E). The amount of the release agent to be added is preferably 0.1 to 2.5 parts by weight based on 100 parts by weight of the polyarylene sulfide resin (A) because excessive addition of the release agent causes problems such as oozing out on the surface of the molded piece.

The resin composition of the present invention can be prepared by equipment and a method generally used for preparing a synthetic resin composition. Generally, necessary components are mixed, melt-kneaded using a single-screw or twin-screw extruder, and extruded to form molding pellets. The temperature of the resin at the time of melt-kneading is preferably 350 ° C. or lower to prevent the thermal decomposition of magnesium hydroxide.

The polyarylene sulfide resin composition prepared as described above must have ΔY satisfying the following formula (1).

ΔY> b / (a + b + c) × (18/58) × 90 (1) (Here, ΔY is measured from 350 ° C. at a rate of 10 ° C./min in a nitrogen atmosphere using a thermogravimetric analyzer. Thermogravimetric change (%) when heated to 450 ° C, where a, b, and c are components (A)
, (B), and (C). If magnesium hydroxide undergoes significant thermal decomposition during melt-kneading, ΔY becomes a small value, and sufficient tracking resistance cannot be obtained. When the above formula (1) is satisfied, sufficient (90% or more) magnesium hydroxide remains in the resin composition, and good tracking resistance is obtained. Especially when the remaining magnesium hydroxide is less than 90%,
The balance between mechanical strength and tracking resistance is very poor.

The material pellets thus obtained can be molded by a generally known thermoplastic resin molding method such as injection molding, extrusion molding, vacuum molding, compression molding or the like. Molding.

[0031]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
The evaluation methods evaluated in Examples and Comparative Examples are as follows. (Tracking Resistance Test) CTI (Comparative Tracking Index) was measured according to IEC 112 Third Edition. (TGA Heat Loss) Using a thermogravimetric analyzer (TGA) under a nitrogen atmosphere with TGA7 manufactured by PerkinElmer, Inc.
The thermogravimetric change (%) when the temperature was raised from 350 ° C. to 450 ° C. at a rate of 10 ° C./min was measured to determine ΔY. As a sample, 10 mg of powder obtained by grinding each pellet was used. (Tensile test) Tensile strength and tensile elongation were measured according to ISO527. (Release Resistance of Molded Piece) The molded piece shown in FIG. 1 was molded under the following conditions by an injection molding machine, the force when the molded piece was extruded from the mold was measured, and the measured value was used as the mold release resistance. Value (N).

Release resistance measuring machine; MOBAC cavity pressure sensor Injection molding machine; Nikko J75SSII-A Cylinder temperature; 310 ° C Injection time; 12 seconds Cooling time; 45 seconds Mold temperature; 140 ° C Examples 1-7 and comparison Examples 1 to 6 The components shown in Table 1 were mixed in a Henschel mixer for 5 minutes, and the mixture was subjected to a twin-screw extruder in Examples 1 to 7 and Comparative Examples 1 to 4 at a resin temperature of 340 ° C. and Comparative Examples 5 to 6 Was melt-kneaded at a resin temperature of 360 ° C. to form pellets of the resin composition. Then, the tracking resistance test piece and the tensile test piece were molded at a cylinder temperature of 320 ° C. and a mold temperature of 150 ° C. using an injection molding machine and evaluated. Table 1 shows the results. Examples 8 to 9 The components shown in Table 2 were mixed with a Henschel mixer for 5 minutes, and the mixture was melted and kneaded at a resin temperature of 340 ° C. in a twin-screw extruder to prepare pellets of a resin composition. Then, the tracking resistance test piece and the tensile test piece were molded at a cylinder temperature of 320 ° C. and a mold temperature of 150 ° C. using an injection molding machine and evaluated. In addition, release resistance evaluation was also performed. Table 2 shows the results.

The specific substances of each component used in Examples and Comparative Examples are as follows.・ (A) Polyphenylene sulfide (PPS) resin; Fortron KPS, manufactured by Kureha Chemical Industry Co., Ltd. ・ (B) Magnesium hydroxide B-1; average particle diameter 0.83 μm, cumulative weight 83% with particle diameter of 1 μm or less, surface Treatment agent [A-174 (γ-
(Methacryloxypropyltrimethoxysilane)] 3% by weight B'-2; average particle diameter 0.84 μm, cumulative weight 50% with a particle diameter of 1 μm or less, surface treatment agent [A-174 (γ-
(Methacryloxypropyltrimethoxysilane)] 3% by weight B'-3: average particle diameter 0.84 μm, cumulative weight 65% with a particle diameter of 1 μm or less, surface treatment agent [A-174 (γ-
Methacryloxypropyltrimethoxysilane)] 3% by weight B'-4; average particle diameter 1.05 μm, cumulative weight 72% with a particle diameter of 1 μm or less, surface treatment agent [A-174 (γ-
Methacryloxypropyltrimethoxysilane)] 3% by weight B-5; average particle diameter 0.83 μm, cumulative weight 83% with a particle diameter of 1 μm or less, 3% by weight of a surface treating agent (sodium salt of distearyl phosphate) Treated B-6: average particle size 0.83 μm, cumulative weight 83% with particle size 1 μm or less, surface treatment agent (glycerin monostearate) 3
(C) Inorganic filler Glass fiber with an average fiber diameter of 13 μm and a fiber length of 3 mm (D) Olefin-based copolymer Ethylene / octene copolymer ・ (E) Release agent E-1; Pentaerythritol tristearate E-2; polyethylene wax (Sun wax 165P manufactured by Sanyo Chemical)

[0034]

[Table 1]

[0035]

[Table 2]

[Brief description of the drawings]

FIG. 1 is a diagram showing the shape of a molded product for evaluating release resistance used in Examples, (a) is a top view, and (b) is a front view.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) C08K 9/06 C08K 9/06 // (C08L 81/02 (C08L 81/02 23:00) 23:00 (72) Inventor Hidemi Kondo 973 Miyajima, Fuji-shi, Shizuoka Prefecture F-term within Polyplastics Co., Ltd. DE076 DE097 DE107 DE117 DE137 DE147 DE187 DE237 DG057 DJ007 DJ017 DJ037 DJ047 DJ057 DK007 DL007 FA047 FA087 FB086 FB106 FB116 FB136 FB146 FD017 FD206 GQ01

Claims (5)

[Claims] (A) Polyarylene sulfide resin 100
(B) 50 to 300 parts by weight of magnesium hydroxide having an average particle size of 1 μm or less and a cumulative weight of 70% or more having a particle size of 1 μm or less as a particle size distribution. A polyarylene sulfide resin composition containing 0 to 350 parts by weight of a fibrous and / or non-fibrous filler, wherein the polyarylene sulfide resin composition has ΔY satisfying the following formula (1): A sulfide resin composition. ΔY> b / (a + b + c) × (18/58) × 90 (1) (Here, ΔY is measured from 350 ° C. to 450 ° C. at a rate of 10 ° C./min in a nitrogen atmosphere using a thermogravimetric analyzer. The thermogravimetric change (%) when the temperature is raised, where a, b, and c are components (A)
, (B), and (C). ) 2. The polyarylene sulfide resin composition according to claim 1, wherein (B) magnesium hydroxide is surface-treated with an acrylic silane compound. 3. The composition according to claim 1, further comprising 1 to 50 parts by weight of (D) an olefin polymer and / or an olefin copolymer based on 100 parts by weight of the polyarylene sulfide resin (A). The polyarylene sulfide resin composition according to the above. 4. The method according to claim 1, further comprising the step of:
(A) 100 parts by weight of polyarylene sulfide resin
4. The method according to claim 1, wherein the composition is 0.1 to 2.5 parts by weight.
Item 7. The polyarylene sulfide resin composition according to Item 1. 5. A molded product obtained by injection molding the polyarylene sulfide resin composition according to claim 1.