JP3501165B2 - Polyarylene sulfide resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyarylene sulfide resin composition, and more specifically, it retains excellent heat resistance and flame retardancy of polyarylene sulfide resin, and has a linear expansion coefficient close to that of metal and toughness. , A polyarylene sulfide resin composition having excellent fluidity and chemical resistance.

[0002]

2. Description of the Related Art In recent years, polyarylene sulfide resins have excellent chemical resistance, mechanical properties, heat resistance, flame retardancy, etc.
In a wide range of fields such as electric and electronic fields and automobile parts,
It is used as an excellent engineering plastic.

Thermosetting resins have hitherto been used as sealing resins for electronic parts and the like, but thermoplastic resins have recently attracted attention because of their low productivity and difficulty in recycling. Has been done. Among them, polyarylene sulfide resins have been extensively studied because of their excellent heat resistance and flame retardancy.

When such a thermoplastic resin is used for encapsulating a transistor, an IC or the like, in order to form the lead wire, the bonding wire, etc. without cutting or deforming the resin, the molecular weight of the resin is lowered and the linear expansion is performed. It is important that the coefficient be close to the metal.

Therefore, it is known that the linear expansion coefficient is made to be close to that of a metal by mixing a large amount of filler, but on the other hand, the fluidity is lowered and the mechanical strength of a molded article is lowered. New problems such as cracks occurred.

In order to solve such a problem, for example, Japanese Patent Publication No. 5-18351 discloses a polyarylene sulfide resin (hereinafter sometimes referred to as PAS) containing a modified vinyl aromatic compound and an olefin compound. By adding the copolymer and the silane coupling agent of
Methods for improving mechanical strength have been proposed. However, although it has some effect of improving the toughness, it cannot be said to be sufficient.

Further, in Japanese Patent Laid-Open No. 63-17549, an olefin-based copolymer containing an α-olefin and an α, β-unsaturated acid glycidyl ester in a polyphenylene sulfide resin (hereinafter sometimes referred to as PPS). A method of adding coalescence has been proposed. However, in this olefin-based copolymer, heat resistance and chemical resistance are lowered due to insufficient compatibility with PPS, and the element and sealing are caused due to insufficient bonding force with the element. There is a problem of peeling from the resin for use.

Further, JP-A-4-153262 discloses that PPS containing an amino group (hereinafter, aminated PPS).
Sometimes called. ) And an ethylene copolymer composed of ethylene, an α, β-unsaturated carboxylic acid alkyl ester and maleic anhydride, have been proposed. However, when the aminated PPS used has a melt viscosity of 400 poise or more, there is a problem that the resin composition has poor fluidity and poor moldability. That is,
When the resin composition was used for IC encapsulation, the bonding wire was deformed and was unsuitable as an encapsulating material.

The present invention aims to solve the above problems. That is, an object of the present invention is to provide a polyarylene sulfide resin composition which is particularly suitable for sealing electronic parts such as ICs and which has excellent heat resistance and flame retardancy, and further has excellent mechanical strength and solvent resistance. Another object is to provide a polyarylene sulfide resin composition having a small coefficient of linear expansion anisotropy.

[0010]

The invention according to claim 1 for solving the above-mentioned problems is a polyarylene.
Ruffido resin, silica, ethylene, α, β-unsaturation
From carboxylic acid alkyl esters and maleic anhydride
Has a three-dimensional structure
Poly containing zinc oxide whiskers
An arylene sulfide resin composition, the invention according to claim 2, wherein the polyarylene sulfide resin is a polyarylene sulfide resin composition according to claim 1 is a polyarylene sulfide of the amino group-containing, according invention according to claim 3, wherein the polyarylene sulfide resin composition is an IC encapsulating resin composition wherein 請
The polyarylene sulfide resin composition according to claim 1 or 2 .

The polyarylene sulfide resin composition of the present invention will be described in detail below.

—Polyarylene Sulfide Resin— The polyarylene sulfide fide (hereinafter sometimes referred to as PAS) resin in the present invention is a compound represented by the general formula — (Ar—S—) _n — and known per se. Can be mentioned. Here, -Ar- is, for example, a divalent aromatic residue containing at least one carbon 6-membered ring as shown in the following (Chemical formula 1), and further, in each aromatic ring, F, Cl, Atoms such as halogen atoms such as Br,
Alternatively, a substituent such as an alkyl group such as a methyl group, a nitro group, a carboxylic acid / metal salt, an amino group or a phenyl group may be introduced.

[0013]

[Chemical 1]

The PAS resin can be obtained, for example, by subjecting a dihaloaromatic compound and a sulfur source to a polycondensation reaction in an organic polar solvent by a method known per se.

Examples of the dihalo aromatic compound include dihalobenzenes such as m-dihalobenzene and p-dihalobenzene; 2,3-dihalotoluene, 2,5-dihalotoluene, 2,6-dihalotoluene, 3,4-dihalotoluene, 2, 5-dihaloxylene, 1-ethyl-2,5-
Dihalobenzene, 1,2,4,5-tetramethyl-3,
6-dihalobenzene, 1-normalhexyl-2,5-
Alkyl-substituted dihalobenzenes such as dihalobenzene, 1-cyclohexyl-2,5-dihalobenzene or cycloalkyl-substituted dihalobenzenes; 1-phenyl-2,
Aryl-substituted dihalobenzenes such as 5-dihalobenzene, 1-benzyl-2,5-dihalobenzene, 1-p-toluyl-2,5-dihalobenzene; dihalobiphenyls such as 4,4′-dihalobiphenyl, 1,4 Examples thereof include dihalonaphthalene, dihalonaphthalene, 1,6-dihalonaphthalene, and 2,6-dihalonaphthalene. The two halogen elements in these dihalo-aromatic compounds are respectively fluorine, chlorine, bromine or iodine, which may be the same or different from each other.

As the sulfur source, alkali metal sulfides such as lithium sulfide and sodium sulfide, calcium sulfide,
Examples thereof include alkaline earth metal sulfides such as barium sulfide. Further, the alkali metal sulfide or alkaline earth metal sulfide is an alkali metal hydrosulfide such as lithium hydrosulfide or sodium hydrosulfide, or an alkaline earth metal hydrosulfide such as calcium hydrosulfide or barium hydrosulfide. It may be obtained by reacting each with a base such as an alkali metal hydroxide.

Examples of the organic polar solvent include organic solvents such as amide compounds, lactam compounds, urea compounds, cyclic organic phosphorus compounds and sulfone compounds. Preferred examples of these are N-alkyl lactams, especially N-alkyl pyrrolidone and sulfolane.

In the present invention, in the polycondensation reaction, a branching agent such as an active hydrogen-containing haloaromatic compound, a polyhaloaromatic compound having 3 or more halogen atoms in one molecule, a haloaromatic nitro compound, etc. Alternatively, the PAS resin may be a PAS resin obtained by appropriately adding a molecular weight modifier such as a monohalo aromatic compound to the reaction system. By using the branching agent, the molecular weight modifier, etc., the PAS resin produced by the polycondensation reaction can be increased in the degree of branching, further increased in the molecular weight, or reduced in the residual salt content.
The properties of the S resin are improved.

A preferred example of the PAS resin is a polyphenylene sulfide (hereinafter sometimes referred to as PPS) resin represented by the following (Chemical formula 2).

[0020]

[Chemical 2]

The PPS resin is generally commercially available under the trademark "Ryton" from Phillips Petroleum Company, USA. Its manufacturing method is described in US Pat. No. 3,354,12.
No. 9 specification and Japanese Patent Publication No. 45-3368 corresponding thereto
Japanese Patent Laid-Open Publication No. S60-25029 discloses that paradichlorobenzene and sodium sulfide (Na ₂ S · H ₂₎ are heated under pressure in an N-methylpyrrolidone solvent at 160 to 250 ° C.
It can be produced by reacting with O).
In addition, Japanese Examined Patent Publication No. 52-12240 and Japanese Examined Patent Publication No. 53-2
When a catalyst such as lithium acetate or lithium chloride is used in combination as disclosed in JP-A-5588 and JP-B-53-25589, a PPS resin having a higher degree of polymerization can be produced.

The PAS resin in the present invention is an amino group-containing polyarylene sulfide containing an arylene sulfide unit containing an amino group, which is represented by the following formula (Formula 3) (hereinafter referred to as aminated PAS). It is preferable that it is a resin. By using the aminated PAS resin, the compatibility with the specific elastomer is improved.

[0023]

[Chemical 3]

However, in the formula, Ar represents an aromatic residue as in formula 1. Further, the position where the amino group in the above formula is bonded to the aromatic ring is arbitrary. In the above formula, R ¹ and R ² represent a hydrogen atom and a hydrocarbon group, respectively, and R ¹ and R ² may be the same as or different from each other. When R ¹ and R ² are hydrocarbon groups, examples of the hydrocarbon group include lower saturated hydrocarbon groups such as methyl group, ethyl group and propyl group, and aromatic hydrocarbon groups such as phenyl group. be able to. Preferred as R ¹ and R ² is a hydrogen atom. In the above formula, n represents a positive number, and is specifically determined according to the structure of the aromatic nucleus to which the amino group is bonded 1
Is any positive number from ˜8.

In the amino group-containing polyarylene sulfide resin, the content of the amino group-containing arylene sulfide unit is usually 0.1 mol% or more, preferably 0.1 to 30 mol%, more preferably 0.1. It is 3 to 10 mol%, particularly preferably 0.3 to 2 mol%.

When the content is less than 0.1 mol%, the amount of introduced amino groups is small, and therefore the effect of improving the physical properties such as strength is the same as in the case of using the amino group-free PAS resin. If the amount exceeds 30 mol%, the crystallinity of the PAS resin is reduced and the physical properties such as heat resistance are deteriorated, which is not preferable.

The aminated PAS resin can be obtained by blending a halogenated aromatic compound having an amino group during the polycondensation reaction of the PAS resin and subjecting it to a polycondensation reaction.

Examples of the halogenated aromatic compound containing an amino group include chloro-substituted anilines such as monochloroaniline, N-alkylmonochloroaniline, dichloroaniline and N-alkyldichloroaniline. . The halogenated aromatic compound containing an amino group is not limited to such anilines and may be any substance containing an amino group in the aromatic ring. The halogenated aromatic compounds containing an amino group may be used alone or in combination of two or more.

The polyarylene sulfide resin in the present invention is preferably uncrosslinked or partially crosslinked PAS resin.

The melt viscosity of PAS in this invention at 300 ° C. and a shear rate of 200 S ⁻¹ is usually 5 to 30 Pa · s.
And preferably 7 to 27 Pa · s, especially 10 to 25 P
a · s is preferable. If the melt viscosity is less than 5 Pa · s, the strength will be poor, and if it exceeds 30 Pa · s, the moldability will be poor, and when used for IC encapsulation, problems such as deformation of the bonding wire during molding will occur. In addition, P
The sodium content of AS is preferably 150 ppm or less. If it exceeds 150 ppm, it is not preferable because corrosion of wires and the like is likely to occur.

The blending amount of the PAS resin in the present invention is usually 30 to 60% by weight, preferably 35 to 55% by weight, particularly 40% by weight based on the total amount of the PAS resin, the silica and the specific elastomer. -50% by weight is preferred. If the content is less than 30% by weight, the viscosity will be high and the moldability will be poor. On the other hand, if it exceeds 60% by weight, the linear expansion coefficient becomes large.

-Silica- As the silica in the present invention, fused silica and / or
Alternatively, crystalline silica can be used. The silica may or may not be surface-treated with a silane coupling agent such as epoxysilane or aminosilane. The average particle size of the silica is preferably 50 μm or less. If the average particle size of silica exceeds 50 μm, the fluidity of the resin composition may decrease. The sodium content of the silica is preferably 5 ppm or less, and particularly preferably 3 ppm or less.
If it exceeds 5 ppm, Na ⁺ may be eluted into the element such as IC to reduce the reliability of the element.

The blending amount of the silica is the PAS
40 to 70% by weight, based on the total amount of the resin, the silica and the specific elastomer, and 45 to 65% by weight.
Is preferable, and particularly 50 to 60% by weight is preferable. If the content is less than 40% by weight, the compounding effect cannot be obtained, while if it exceeds 70% by weight, the fluidity may be poor.

-Ternary Copolymer Elastomer- The elastomer in the present invention is ethylene, α, β-
It is a terpolymer elastomer composed of an unsaturated carboxylic acid alkyl ester and maleic anhydride.

The α, β-unsaturated carboxylic acid alkyl ester is preferably an alkyl ester of an unsaturated carboxylic acid having 3 to 8 carbon atoms such as acrylic acid and methacrylic acid, and among them, ethyl acrylate and acryl N-butyl acid and methyl methacrylate are preferred.

The proportion of the monomer component in this elastomer is 50 to 90% by weight of ethylene, preferably 60 to 85% by weight, and 5 to 49% by weight of α, β-unsaturated carboxylic acid alkyl ester. And preferably 7
-45% by weight, maleic anhydride is 0.5-10% by weight, preferably 1-8% by weight. When the ratio of the monomer component is within this range, the mechanical strength such as excellent toughness and the fluidity are excellent.

This specific elastomer is preferably blended in an amount of 3 to 30 parts by weight with respect to the PAS resin. Three
If the amount is less than parts by weight, the compounding effect may not be obtained, and excellent toughness and fluidity may not be achieved. On the other hand, 30
If it exceeds the weight part, the rigidity, heat resistance and flame retardancy may be impaired.

—Zinc Oxide Whiskers— The polyarylene sulfide resin composition in the present invention is a resin composition containing at least the PAS resin, particularly the aminated PAS resin, silica, and a specific elastomer. By blending zinc oxide whiskers having a three-dimensional structure, a resin composition having a particularly small anisotropy of linear expansion coefficient can be obtained.

The zinc oxide whiskers having this three-dimensional structure are roughly shaped like tetrapots having linear portions extending from the center of a regular tetrahedron to each vertex. Thus, the zinc oxide whiskers according to the present invention have a three-dimensional peculiar structure, so that the coefficient of linear expansion of the resin composition has no anisotropy and the mechanical strength has no anisotropy.

As the material of the zinc oxide whiskers, at least the surface of the whiskers may be made of zinc oxide, or the whiskers themselves may be made of zinc oxide. The zinc oxide whiskers used in the present invention can be obtained by heating and oxidizing metallic zinc in an oxygen atmosphere. The bulk specific gravity of the zinc oxide whiskers is preferably 0.02 to 0.5 g / cm ² .

The zinc oxide whisker content is preferably 10 parts by weight or more based on the silica content. If it is less than 10 parts by weight, the effect of reducing the anisotropy of the coefficient of linear expansion may not be obtained.

-Other Components-In the polyarylene sulfide resin composition according to the present invention, in addition to the above-mentioned components, other components may be added / blended as necessary within the range not impairing the object of the present invention. Good.

Examples of the other components include inorganic fillers, various additives such as antioxidants, heat stabilizers, lubricants, coloring agents, thermoplastic resins such as polyamide, epoxy resin, silicone resin, polyolefin and / or the like. Examples thereof include thermosetting resins, hydrogenated SBS, hydrogenated NBR, rubbers such as silicone rubber and fluororubber, and pigments.

Examples of the inorganic filler include oxides such as calcium oxide, magnesium oxide, titanium oxide and alumina oxide, hydroxides such as aluminum hydroxide, magnesium hydroxide and calcium hydroxide, magnesium carbonate, calcium carbonate and dolomite. Such as carbonates, barium sulfate, calcium sulfate, magnesium sulfate, and other sulfates,
Sulfites such as calcium sulfite, silicates such as calcium silicate, silicon carbide, silicon nitride, ceramics such as boron nitride, calcium titanate whiskers, alumina whiskers, magnesia whiskers, graphite whiskers, silicon carbide whiskers and other whiskers, glass Inorganic fibers such as fibers, aramid fibers and carbon fibers, as well as talc, clay, mica, glass beads, carbon black, diatomaceous earth, asbestos and zeolite can be mentioned.

The contents of the other components described above can be appropriately selected within a range that does not impair the object of the present invention.

—Preparation of Polyarylene Sulfide Resin Composition— The polyarylene sulfide resin composition according to the present invention comprises the PAS resin, the silica, the terpolymer elastomer, and other components selected as necessary. Or blending the PAS resin, the silica, the terpolymer elastomer, the zinc oxide whiskers having a three-dimensional structure, and other components selected as necessary, which are, for example, melt-kneaded. It can be prepared by

The melt-kneading can be carried out by an ordinary known method, but in any case, by uniformly mixing and dispersing the respective components in the resin,
It is a predetermined resin composition.

For the melt-kneading, a usual twin-screw extruder, a single-screw extruder or the like can be preferably used.

The conditions for the melt-kneading are not particularly limited, but extremely high temperatures and extremely long residence times are avoided in order to limit decomposition or foaming of other components added as necessary. Is preferred. The specific temperature is usually 280 to 350 ° C, preferably 285 to 330 ° C.

The thus-prepared polyarylene sulfide resin composition is usually granulated into a shape and size suitable for secondary processing materials such as pellets, particularly for mold molding materials and injection molding materials. Or it is cut and acquired.

[0051]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited to these examples. In the following examples and comparative examples,
Fused silica FB35 (manufactured by Denki Kagaku Kogyo KK), FB74 (manufactured by Denki Kagaku Kogyo KK) whose surface is not treated as silica
And FS784 (manufactured by Denki Kagaku Kogyo Co., Ltd.) were used.
Their average particle size and sodium content are as follows.

FB35; average particle size 11.8 μm, Na content 1.0 ppm FB74; average particle size 31.5 μm, Na content 0.7 p
pm FS784; average particle size 12.5 μm, Na content 1.1
As the ppm elastomer, M191 manufactured by Asahi Kasei Corporation
3 (hydrogenated styrene butadiene block copolymer),
Bondine-AX8390 (a terpolymer of 68% by weight of ethylene, 30% by weight of ethyl acrylate and 2% by weight of maleic anhydride) manufactured by Sumitomo Chemical Co., Ltd. was used. As whiskers, Panatetra (bulk specific gravity 0.3 g / cm ³ , surface untreated) manufactured by Matsushita Amtec Co., Ltd., which is a zinc oxide whisker having a three-dimensional structure, and potassium titanate whiskers manufactured by Otsuka Chemical Co., Ltd. Tismo D
101 (not having a three-dimensional structure) was used.

[0053] -PPS1 preparation of (linear PPS resin) - to the polymerization reactor fitted with a stirrer, hydrated sodium sulfide _{(Na 2 S · 5H 2 O} ) 840 mol of LiCl830 moles N- methylpyrrolidone (hereinafter , NMP.)
Then, 510 liter of water was added thereto, and dehydration treatment was performed for 1 hour while maintaining the temperature at 145 ° C. under reduced pressure. Then, the reaction system is at 45 ° C.
After cooling to room temperature, p-dichlorobenzene 89 was added to the polymerization reaction tank.
8 mol was added and a polymerization reaction was carried out at 260 ° C. for 3 hours. The polymerization reaction product thus obtained was washed 5 times with hot water, then once with NMP, and finally 3 times with water. Then, by drying at 185 ° C., 300
The melt viscosity at 20 ° C. and a shear rate of 200 S ⁻¹ is 20 Pa · s,
A linear PPS resin having a sodium content of 95 ppm was obtained.

-Production of PPS2 (aminated PPS resin) -In the dehydration treatment, the compounding amount of LiCl was 833 mol, and the polymerization reaction was carried out by adding 912 mol of p-dichlorobenzene and 41.5 mol of dichloroaniline, and adding 240 An aminated PPS resin was obtained in the same manner as in the case of PPS1 except that the polymerization reaction was carried out at 5 ° C. for 5 hours. The resulting aminated PPS resin has a melt viscosity of 19 P at 300 ° C. and a shear rate of 200 S ^−1.
The a · s and sodium content were 90 ppm.

Reference Examples 1 to 6 and Comparative Examples 1 to 4 The linear PPS resin or aminated P obtained as described above
The PS resin and the silica and elastomer shown in Table 1 were dry-blended with the composition and compounding ratio shown in Table 1. This dry blended product was melt-kneaded and granulated at a resin temperature of 290 ° C. using a twin-screw extruder to obtain pellets of the PPS resin composition. Next, a test piece was prepared by molding the obtained pellet at a cylinder temperature of 290 ° C. and a mold temperature of 135 ° C.

[0056]

[Table 1]

The test pieces of the obtained PPS resin composition were used to evaluate the Izod strength, flexural bending amount, melt viscosity and solvent resistance, and the results are shown in Table 1. Izod strength and flexural deflection are measured by ASTM D256
And according to ASTM D790. In addition,
The flexural bending amount was measured for the purpose of evaluating toughness, and the bending amount up to the breaking point in bending evaluation was measured.

The solvent resistance was evaluated by immersing the test piece in trichlene at room temperature, immersing it for 120 hours, and then observing the appearance of the test piece. The solvent resistance is shown in Table 1 as ◯ when there was no change in the test piece, Δ when there was slight swelling, and x when there was obvious swelling.

The melt viscosity of the compound product was measured by using a capillary viscometer at a resin temperature of 310 ° C. and a shear rate of 1,20.
It was measured under the condition of 0 S ^-1 . ( Examples 1 and 2 , Comparative Example 5) Silica, an elastomer, and whiskers were dry blended with the PPS1 or the PPS2 in the composition and the compounding ratio shown in Table 2. Then, a test piece was prepared in the same manner as above.

[0060]

[Table 2]

The test pieces of the obtained PPS resin composition were used to measure the ratio of Izod strength, bending strength, melt viscosity and linear expansion coefficient, and the results are shown in Table 2.

Izod strength and flexural strength measurements are made according to ASTM D256 and ASTM D790, respectively.
The melt viscosity is measured in Reference Examples 1 to 6 and Comparative Examples 1 to
The same procedure as 4 was performed.

Further, in order to evaluate the anisotropy of the coefficient of linear expansion, a sample obtained by cutting from the center of the test piece was heated at a heating rate of 5
The temperature was raised at 0 ° C./min, the linear expansion coefficient of MD and TD at 40 ° C. was measured, and the ratio of linear expansion coefficients (TD / MD) was calculated. The results are shown in Table 2.

[0064]

According to the present invention, it is possible to provide a resin composition having a small coefficient of linear expansion anisotropy, excellent fluidity, toughness, heat resistance and flame retardancy. Further, by using aminated PAS as PAS, it is possible to improve the fluidity and the toughness, among these properties. Further, by blending a zinc oxide whisker having a three-dimensional structure, it is possible to provide a resin composition having particularly small anisotropy of linear expansion coefficient and improved strength. Since the resin composition of the present invention has the above-mentioned features, it can be particularly suitably used for sealing electronic parts such as ICs.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-179791 (JP, A) JP-A-4-123461 (JP, A) JP-A-4-153262 (JP, A) JP-A-5- 127470 (JP, A) JP 62-151460 (JP, A) JP 61-207462 (JP, A) JP 5-140452 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 81/00-81/10 C08K 3/00-13/08

Claims (3)

(57) [Claims] 1. A polyarylene sulfide resin and a silicone
Mosquitoes and ethylene, α, β-unsaturated carboxylic acid alkyl ethers
The terpolymer ella consisting of steal and maleic anhydride.
Storm and zinc oxide whiskers having a three-dimensional structure
Containing polyarylene sulfide
Resin composition. 2. The polyarylene sulfide resin,
The polyarylene sulfide resin composition according to claim 1, which is a polyarylene sulfide having an amino group. 3. The polyarylene sulfide resin composition according to claim 1 or 2 , wherein the polyarylene sulfide resin composition is an IC encapsulating resin composition.