JPH10212408A - Polyphenylene sulfide resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition improved in moldability, processability and solder heat resistance, comprising a specific compound, a crystalline polymide resin, a prescribed metal salt and a fibrous filler. SOLUTION: This polyphenylene sulfide resin is obtained by compounding 100 pts.wt. of a blend of (A) 70-95wt.% of a polyphenylene sulfide having 10-50,000 poise melt viscosity and (B) 30-5wt.% of a crystalline polymide resin, preferably a polyamide 6, a polyamide 46 or a polymide 66 with (C) 0.05-5 pts.wt. of (i) a fatty acid metal salt having >=280 deg.C decomposition temperature, preferably a metal stearate or a metal montanate or (ii) a metal diarylphosphate of the formula (R1 a H or a 1-4C alkyl; R2 and R3 are each a 1-9C alkyl; M is an alkali metal) and (D) 25-100 pts.wt. of a fibrous filler as a reinforcing material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel polyphenylene sulfide resin composition. More specifically, the present invention relates to a polyphenylene sulfide resin composition having excellent solder heat resistance and excellent properties such as flame retardancy, moldability, mechanical strength, and chemical resistance, and is particularly preferably used for surface mount components. I can do it.

[0002]

2. Description of the Related Art Polyphenylene sulfide resin is an engineering plastic excellent in heat resistance, flame retardancy, chemical resistance, etc., and can be molded into various parts by injection molding, extrusion molding, etc., and makes use of these characteristics. Electric
It is applied to electronic equipment parts, automobile equipment parts and precision machine parts. In particular, polyphenylene sulfide resin is excellent in molding flow characteristics in injection molding and has a small shrinkage, so that it is suitable for thin-wall molding and precision molding.

[0003] However, recently, higher functionality, lighter weight,
Reflecting social needs such as cost reduction, molded parts in these fields tend to be required to be thinner, smaller, and more plural than before.

[0004] Therefore, the polyphenylene sulfide resin as a material needs to have sufficient fluidity in a thin portion at the time of molding and a phenomenon that the resin flows out to a parting surface of a mold, that is, so-called burr generation is extremely small. In order to perform thin-wall molding with polyphenylene sulfide resin, it is common to use a polymer with a relatively low molecular weight and low melt viscosity, or to set the injection molding temperature higher than normal conditions and lower the melt viscosity of the polymer to perform molding. Is being done.

[0005] However, these methods have a disadvantage that the amount of burrs generated increases as the melt viscosity decreases. Further, there are problems such as a decrease in mechanical properties and dimensional accuracy of the molded product.

[0006]

SUMMARY OF THE INVENTION The present inventors have found that while maintaining the excellent properties of polyphenylene sulfide resin,
A study was made on a method of compounding a material having high moldability, especially high fluidity and excellent burr properties.

Conventionally, as a method for improving the moldability of polyphenylene sulfide resin, JP-A-55-135160 has been disclosed.
JP-A No. 3-6, a composition comprising a polyphenylene sulfide resin disclosed in Japanese Patent Application Laid-open No.
Japanese Patent No. 4358 discloses a composition comprising a polyarylene thioether resin mixed with a nylon 46 resin. However, it has been found that in order to simultaneously satisfy high fluidity and excellent burr properties in these compositions, heat resistance, which is one of the excellent properties of polyphenylene sulfide resin, is sacrificed. In particular, when a composition composed of polyphenylene sulfide resin and nylon is used for surface mount components, the water in the nylon resin evaporates during soldering using a reflow bath because the nylon resin absorbs much water. In addition, there has been a problem that blisters are generated on the product surface and solder heat resistance is remarkably reduced.

[0008] The object of the present invention is based on the above problems,
An object of the present invention is to provide a resin composition having both excellent moldability and solder heat resistance while maintaining excellent heat resistance, mechanical properties, dimensional stability and the like of polyphenylene sulfide resin.

[0009]

SUMMARY OF THE INVENTION In view of the above situation, the present inventors have attempted to solve the problems of the conventional composition comprising polyphenylene sulfide and polyamide resin by using a melt viscosity of 10 to 50,000 poise. Solder heat resistance of a composition comprising a polyphenylene sulfide resin and a nylon resin by mixing a fatty acid metal salt or a specific diaryl phosphate metal salt having a decomposition temperature of 280 ° C. or higher with a composition comprising a certain polyphenylene sulfide resin and a polyamide resin Has been found to be significantly improved, and it has been found that a highly practical polyphenylene sulfide resin having both excellent moldability and soldering heat resistance can be provided, and the present invention has been accomplished.

That is, according to the present invention, (a) the melt viscosity is 10
Polyphenylene sulfide 7 with ~ 50,000 poise
0 to 95% by weight, and (b) 30 to 30% by weight of the crystalline polyamide resin.
5% by weight of a metal salt of a fatty acid having a decomposition temperature of 280 ° C. or more or a metal salt of a diaryl phosphate represented by the following general formula (1) with respect to 100 parts by weight of the total of component (a) and component (b): (D) a polyphenylene sulfide resin composition comprising 25 to 100 parts by weight of a fibrous filler as a reinforcing material.

[0011]

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(Wherein R ₁ is a hydrogen atom or a group having 1 carbon atom)
And R ₂ and R ₃ represent 1 to 4 carbon atoms.
9 represents an alkyl group, and M represents an alkali metal. Hereinafter, the present invention will be described in detail.

The polyphenylene sulfide resin used in the present invention has, as a structural unit,

[0014]

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Is preferably 70 mol% or more, more preferably 90 mol% or more. In addition, when the constituent unit is less than 30 mol%, preferably less than 10 mol%, the m-phenylene sulfide unit is used.

[0016]

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O-phenylene sulfide unit,

[0018]

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A phenylene sulfide sulfone unit,

[0020]

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A phenylene sulfide ketone unit,

[0022]

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Phenylene sulfide ether unit,

[0024]

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Diphenylene sulfide unit,

[0026]

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Phenylene sulfide units having various functional groups,

[0028]

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(Where R is an alkyl group, a phenyl group, a nitro group, a carboxyl group, a nitrile group, an amino group, an alkoxyl group, a hydroxyl group or a sulfonic acid group). It may not be contained.

Further, even if the polyphenylene sulfide resin used in the present invention is linear, it is cured by heat treatment in an oxygen atmosphere or heat treatment with the addition of a peroxide or the like. Even if the degree of polymerization is increased,
Further, it may be subjected to heat treatment in a non-oxidizing inert gas, or may be a mixture of these structures. Further, the polyphenylene sulfide resin may be one in which ions are reduced by performing a deionization treatment (acid washing, hot water treatment, or the like).

The melt viscosity of the polyphenylene sulfide resin used in the present invention was measured at a temperature of 315 ° C. under a load of 10 k.
g, a melt viscosity measured by a Koka type flow tester using a die having a diameter of 1 mm and a length of 2 mm is 10 to 50.
000 poise, preferably 100 to 10,000 poise,
More preferably, those having 250 to 6000 poise can be suitably used. If the melt viscosity exceeds 50,000 poise, the moldability during injection molding deteriorates, which is not preferable. If the melt viscosity is less than 10 poise, the mechanical strength decreases, which is not preferable. The amount of the polyphenylene sulfide resin used in the present invention is 70 to 95% by weight. If the amount is less than 70% by weight, heat resistance and water absorption are undesirably reduced. On the other hand, if it exceeds 95% by weight, the effect of improving the moldability is poor, which is not preferable. When the compounding amount is in the range of 70 to 95% by weight, it has both excellent heat resistance and moldability.

The crystalline polyamide resin used in the present invention is a polymer having an amide bond (—NH—CO—) in the main chain, and among these, usually polycaproamide (nylon 6) and polyundecaneamide ( Known materials such as nylon 11), polydodecaneamide (nylon 12), polytetramethylene adipamide (nylon 46), polyhexamethylene adipamide (nylon 66), polyhexamethylene sepacamide (nylon 610) are used. it can.

As the polymerization method of the crystalline polyamide resin, a generally known method can be adopted. Specifically, ring-opening polymerization of ε-caprolactam, 6-aminocaproic acid, ω-laurolactam, etc., polycondensation of 11-aminoundecanoic acid, hexamethylenediamine and dicarboxylic acid such as adipic acid, sebacic acid, dodecadioic acid, etc. It is obtained by polycondensation, polycondensation of diaminobutane and adipic acid, and the like.

Of these crystalline polyamide resins, nylon 6, nylon 66 and nylon 46 have a melting point of 220.
Since the temperature is not less than ° C, it is suitably used in order to obtain a polyphenylene sulfide resin composition having both excellent moldability and solder heat resistance, which is the object of the present invention.

The degree of polymerization of the crystalline polyamide resin is not particularly limited, and the relative viscosity (1 g of the polymer dissolved in 100 ml of 98% concentrated sulfuric acid and measured at 25 ° C.) is 1.0 to 5.
The crystalline polyamide resin in the range of 0 can be arbitrarily selected according to the purpose. The compounding amount of the crystalline polyamide resin to the composition of the present invention is 5 to 30% by weight. When the amount of the crystalline polyamide resin is 5% by weight or less, the effect of improving the fluidity is poor, and when the amount is 30% by weight or more, the heat resistance of the composition is significantly deteriorated.

The fatty acid metal salts used in the present invention include saturated fatty acids having 16 to 38 carbon atoms, such as metal salts of palmitic acid, stearic acid, oleic acid, arachiic acid, behenic acid, montanic acid and the like. Examples of the metal salt include zinc, aluminum, calcium, potassium, sodium, magnesium, iron, cobalt, lithium, nickel, copper, and lead.

The fatty acid metal salt has a decomposition temperature of 280 ° C. or higher,
Preferably, it is 300 ° C. or higher, which is a general processing temperature of polyphenylene sulfide. If the decomposition temperature is lower than 280 ° C., the polyphenylene sulfide composition is thermally decomposed in a processing machine such as an extruder in the production stage, and the object of the present invention cannot be achieved. The decomposition temperature is measured by a differential thermal balance (TGA) method, and is the temperature at which the weight loss is 5%.

Of these metal salts of fatty acids, metal salts of stearic acid and montanic acid are preferred because of their high decomposition temperature, and specifically zinc stearate, potassium stearate and stearate having a decomposition temperature of 280 ° C. or higher. Calcium phosphate, zinc montanate, calcium montanate, sodium montanate and the like are preferred.

The diaryl phosphate metal salt used in the present invention is a compound represented by the general formula (1).

[0040]

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(Wherein R ₁ is a hydrogen atom or a group having 1 carbon atom)
And R ₂ and R ₃ represent 1 to 4 carbon atoms.
9 represents an alkyl group, and M represents an alkali metal. In the general formula (1), examples of the alkyl group having 1 to 4 carbon atoms represented by R ₁ include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl,
Examples of the alkyl group having 1 to 9 carbon atoms represented by R ₂ and R ₃ include, in addition to the alkyl group having 1 to 4 carbon atoms represented by R ₁ , amyl and tertiary amyl. , Hexyl, heptyl, octyl, isooctyl,
Tertiary octyl, 2-hexylhexyl, nonyl and the like can be exemplified. Examples of the alkali metal represented by M include lithium, sodium, and potassium.

In the compound represented by the general formula (1), R ₁ is a hydrogen atom or a methyl group, and R ₂ is a compound having 1 to 1 carbon atoms.
Particularly preferred are compounds wherein the alkyl group of 4, R ₃ is a tertiary alkyl group such as tert-butyl or tertiary amyl, and M is lithium or sodium, and commercially available products include 2,2′-methylenebisphosphate (4,6-di-t-
Butylphenyl) sodium (trade name NA-11, manufactured by Adeka Argus).

These fatty acid metal salts, or a compound represented by the general formula (1)
The amount of the diaryl phosphate metal salt represented by
It is 0.05 to 5 parts by weight, preferably 0.1 to 3 parts by weight, based on 100 parts by weight of the polyphenylene sulfide / crystalline polyamide resin composition. When the addition amount is less than 0.05 parts by weight, the effect of adding the fatty acid metal salt or the diaryl phosphate metal salt is not sufficient.
If the amount exceeds 5 parts by weight, an improvement in solder heat resistance is observed, but it is not preferable because mechanical strength, particularly, weld strength and electrical characteristics are reduced. When the amount of addition is within this range, when the composition of the present invention is used for a surface mount component, blistering does not occur on the product surface even when soldering is performed using a reflow bath, and the solder has heat resistance. The composition which is excellent in is obtained.

These metal salts of fatty acids or metal salts of diaryl phosphates may be used alone or in combination of two or more.
Mixtures of more than one type can also be used.

Examples of the fibrous filler usable in the present invention include glass fibers, carbon fibers, metal fibers, and potassium titanate whiskers. Of these, glass fibers are preferred. Roving, chopped strand, milled fiber or the like having a fiber diameter of 3 to 20 μm is used as the glass fiber. Glass fibers are usually treated with a binder in order to improve the adhesiveness with the resin.Examples of the binder include a urethane-based, epoxy-based or urethane-epoxy combined system or a silane-based coupling agent. Can be

The amount of the fibrous filler used in the present invention is from 25 to 100 parts by weight based on 100 parts by weight of the composition comprising the polyphenylene sulfide resin and the crystalline polyamide resin.
Parts by weight, preferably 30 to 70 parts by weight. If the amount is less than 25 parts by weight, the mechanical strength and heat resistance of the molded product may not be sufficient, which is not preferable. On the other hand, if it exceeds 100 parts by weight, the fluidity and the toughness are significantly reduced, and sufficient characteristics cannot be obtained.

The resin composition of the present invention may be any of various thermosetting resins and thermoplastic resins, for example, epoxy resin, cyanate ester resin, phenol resin, polyimide, silicone resin, polyester resin, without departing from the object of the present invention. ,
Polyphenylene oxide, polycarbonate, polysulfone, polyethersulfone, polyetherketone,
One or more of polyether ether ketone, polyphenylene sulfide sulfone, polyphenylene sulfide ketone and the like can be used as a mixture.

The resin composition of the present invention may contain inorganic fillers such as calcium carbonate, mica, calcium sulfate, kaolin, clay, silica, talc, glass beads, glass powder, etc., without departing from the object of the present invention. One or more whiskers such as potassium titanate, aluminum borate, and zinc oxide can be used as a mixture.

Further, the composition of the present invention may contain a small amount of a heat stabilizer, an antioxidant, a flame retardant, a flame retardant auxiliary, a mold release agent, a lubricant, a dye, a pigment, etc. as long as the object of the present invention is not impaired. Coloring agents, ultraviolet absorbers, antistatic agents, ion trapping agents, and the like may be added as necessary.

The polyphenylene sulfide resin composition of the present invention can be produced by various methods using the above-mentioned components. For example, a heat-melt kneading method using a single-screw extruder, a twin-screw extruder, a kneader, a Brabender or the like can be mentioned, and among them, a melt-kneading method using a twin-screw extruder is most preferable. The kneading temperature at this time is not particularly limited, but can be arbitrarily selected from 280 to 400 ° C.

The composition of the present invention thus obtained is
Conventionally known methods can be used to form various connector parts, various switch parts, thin-walled molded articles, and other various shapes, and processing methods such as injection molding are possible. As a specific application field, it can be widely used as a molding material having excellent heat resistance, dimensional stability, molding workability, etc. in the field of industrial materials such as automobiles, electrics, electronics, and machines.

[0052]

EXAMPLES The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

The melt viscosity of the polyphenylene sulfide produced in the following Reference Examples was measured at 300 ° C. with a load of 10 kg using a Koka type flow tester (die; φ = 1.0 mm, L = 2 mm). .

The flow length and burr length in the examples are values obtained by the following measuring methods.

As shown in FIG. 1, A: a bar flow (10 × 0.5 mmt) mold having a clearance of 10 μm was used, and the resin composition of the present invention was injected into an injection molding machine (Sumitomo Heavy Industries, SY).
Using CAP S-165 / 75), an injection pressure of 120
When molded at 0 kg / cm ^2, the distance filled with the resin was determined as the flow length, and the burr generated in the clearance portion of A was measured using a universal projector to determine the burr length.

[0056] Reference Example 1 (polyphenylene sulfide) 15 l autoclave, the temperature was raised to N- methyl-2-pyrrolidone 5 l was charged in 120 ℃, Na ₂ S ·
2.8H ₂ O (1866 g) was charged, and the temperature was gradually raised to 205 ° C. while stirring over about 2 hours, and 407 g of water was added.
Distilled. After the system was cooled to 140 ° C., 2150 g of p-dichlorobenzene was added, the temperature was raised to 225 ° C., and polymerization was performed for 3 hours.
Polymerization was performed at 50 ° C. for 3 hours.

After completion of the polymerization, the remaining slurry was poured into a large amount of water to precipitate a polymer, separated by filtration, washed with pure water, and then heated and vacuum-dried overnight to convert the polymer into a simple substance. Released. The melt viscosity of the obtained polyphenylene sulfide (measured by a Koka type flow tester) was 280 poise. The polymer thus obtained was further treated at 235 ° C. in an air atmosphere to obtain polyphenylene sulfide having a melt viscosity of 1540 poise. This polymer is referred to as PPS.

Reference Example 2 (Nylon 66) UBE nylon 2020H (manufactured by Ube Industries) was used as nylon 66. This polymer is designated as PA66.

Examples 1 and 2 and Comparative Examples 1 to 5 The PPS and PA66 obtained in Reference Example 1 and sodium montanate as the fatty acid metal salt were uniformly mixed in advance in a mixing ratio shown in Table 1 using a tumbler. Was mixed.

Then, using a twin screw extruder having a screw diameter of 37 mmφ, glass fibers (diameter 13
While chopped strands (μm, length 3 mm) were supplied from a side feeder, the mixture was melt-kneaded at a cylinder temperature of 300 ° C. and pelletized. Pellets obtained are 1
After drying at 20 ° C. for 10 hours, an injection molding machine (Sumitomo Heavy Industries, SYCAP S-165) equipped with the mold shown in FIG.
/ 75), cylinder temperature 310 ° C, injection pressure 1
10 kg under conditions of 200 kg / cm ² and mold temperature of 135 ° C.
Shot injection molded. The flow length and burr length of the obtained molded product were measured. Table 1 shows the results.

Using the same injection molding machine, a cylinder temperature of 310 ° C., a mold temperature of 135 ° C., and an injection pressure of 500 to 500 ° C.
A card edge type connector was molded at 1200 kg / cm ^{2 at} a medium injection speed. The obtained connector was immersed in pure water at 25 ° C. for 24 hours, and then evaluated for solder resistance (blister resistance) using a solder reflow device (SMIC SF-2506HB manufactured by Senju Metal Industry Co., Ltd.). ,
Peak temperature 260 ° C, conveyor speed 300mm / m
When set to in, blisters (blisters) generated in the connector after passing through the reflow device were visually observed. Table 1 shows the results.

As is evident from Table 1, the composition of the present invention is excellent in fluidity, less burrs, and excellent in solder resistance (blister resistance).

[0063]

[Table 1]

Examples 3 to 5 Melting and kneading were performed in the same manner as in Example 1 except that zinc montanate, calcium montanate, and calcium stearate were used in the compounding ratio shown in Table 2 as metal salts of organic fatty acids. , Flow length, burr length, and blister resistance were evaluated. Table 2 shows the results. As is clear from Table 2,
The composition of the present invention has excellent fluidity, less burr,
It turns out that it is excellent in soldering resistance (blister resistance).

[0065]

[Table 2]

Example 6 As a diarylphosphate metal salt, NA-11 (2,2-methylenebis (4,6,2-phosphate) manufactured by Adeka Argus Co., Ltd.
-Di-t-butylphenyl) sodium) was melt-kneaded in the same manner as in the Example except that the compounding ratio shown in Table 2 was used, and the flow length, burr length, and blister resistance were evaluated. Table 2 shows the results. As is clear from Table 2, it is understood that the composition of the present invention has excellent fluidity, less burrs, and excellent solder resistance (blister resistance).

[0067]

The polyphenylene sulfide resin composition of the present invention provides a resin composition excellent in heat resistance, dimensional stability, moldability, etc., and is therefore required to have high fluidity and low burr. It is suitable for components, and particularly suitable for surface mount components due to its excellent solder heat resistance.

[Brief description of the drawings]

FIG. 1 is a bar flow mold used to measure the flow length and burr length of the composition of the present invention.

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Claims (3)

[Claims] (1) 70-95% by weight of a polyphenylene sulfide having a melt viscosity of 10 to 50,000 poise;
(B) 30 to 5% by weight of a crystalline polyamide resin, (c)
Decomposition temperature 2 with respect to the total of 100 parts by weight of the components a and b
A fatty acid metal salt having a temperature of 80 ° C. or higher or a diaryl phosphate metal salt represented by the following general formula (1) is used in an amount of 0.05 to 5:
Parts by weight, (d) 25 to 10 fibrous fillers as reinforcing material
A polyphenylene sulfide resin composition comprising 0 parts by weight. Embedded image (In the formula, R ₁ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ₂ and R ₃ represent an alkyl group having 1 to 9 carbon atoms, and M represents an alkali metal.) 2. The polyphenylene sulfide resin composition according to claim 1, wherein the crystalline polyamide resin is at least one selected from the group consisting of polyamide 6, polyamide 46, and polyamide 66. 3. The polyphenylene sulfide resin composition according to claim 1, wherein the fatty acid metal salt is at least one selected from the group consisting of metal stearate and metal montanate.