JP3079923B2 - Polyphenylene 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 polyphenylene sulfide resin composition useful for applications requiring low burr and thin fluidity, such as connectors, electronic sealing parts and coil sealing parts. is there.

[0002]

2. Description of the Related Art Polyphenylene sulfide resin (hereinafter referred to as P
Abbreviated as PS resin. ) Is suitable for engineering plastics, such as excellent heat resistance, flame retardancy, rigidity, and electrical insulation, so it is used for various electric parts, machine parts, and automobile parts mainly for injection molding. Used in

However, the PPS resin generates burrs at the time of molding relatively frequently, and particularly in applications requiring strong thin-wall fluidity, for example, connectors, electronic parts sealing, coil sealing and the like, remarkable burrs are generated. Therefore, its use is restricted.

[0004] Under such circumstances, several studies have been made for the purpose of reducing burrs of the PPS resin. For example, a method of blending a highly crosslinked PPS resin as a property improving agent (Japanese Patent Application Laid-Open No. 64-9266),
A method of adding a silane compound to a PPS resin (JP-A-63
JP-A-251430), a method of using a specific linear PPS resin and a cross-linked PPS resin in combination as a base polymer, and further using a silane coupling agent (Japanese Patent Laid-Open No. 3-19).
No. 7562).

[0005]

However, conventional burring reduction techniques such as addition of a highly cross-linked PPS resin or addition of a silane compound have the problem of reducing the fluidity of the composition as a whole, In injection molding of precision parts, there have been problems such as poor filling and partial overfilling.

The inventors of the present invention have conducted intensive studies for the purpose of developing a PPS resin which is excellent in all of the above-mentioned properties required for the PPS resin, that is, excellent in thin-wall fluidity and low burr. Specific molecular weight fruit
The use of a PPS resin qualitatively having no crosslinked structure and a linear PPS resin having a specific lower molecular weight than this in a fixed ratio, and further adding a specific alkoxysilane compound to achieve the above object. The present inventors have found that a high-performance PPS resin composition satisfying all of the various properties described above can be obtained, and have reached the present invention.

[0007]

That is, the present invention provides:
(A) The number average molecular weight determined by gel permeation chromatography using 1-chloronaphthalene as a solvent is from 7000 to 1
5000, 5% by weight of a substantially non-crosslinked polyphenylene sulfide resin having a total ash content of 0.3% by weight or less
A polyphenylene sulfide resin mixture 100 comprising at least 50% by weight and (B) a polyphenylene sulfide resin having a number average molecular weight of 3000 to 6000 and having substantially no cross-linked structure and having a number average molecular weight of more than 50% by weight and less than 95% by weight. (C) 0 to 150 parts by weight of at least one kind of fibrous or non-fibrous reinforcing material,
(D) an alkoxysilane compound having at least one functional group selected from an epoxy group, an amino group, a ureido group, an isocyanate group, a hydroxyl group, and a mercapto group.
An object of the present invention is to provide a polyphenylene sulfide resin composition obtained by melt-kneading 1 to 5 parts by weight.

The PPS resin used in the present invention is a repeating unit represented by the following structural formula.

Embedded image It is a polymer containing 70 mol% or more, more preferably 90 mol% or more. When the repeating unit is less than 70 mol%, heat resistance is unfavorably deteriorated. Also PPS
Less than 30 mol% of the repeating unit of the resin can be composed of a repeating unit having the following structure.

[0009]

Embedded image

The PPS resin used as the component (A) in the present invention has a number average molecular weight of 7 determined by gel permeation chromatography using 1-chloronaphthalene as a solvent.
000 to 15,000, having a total ash content of 0.3% by weight or less, has substantially no crosslinked structure, that is, needs to have a linear structure. When a PPS resin that does not satisfy such conditions is used as the component (A), it is difficult to simultaneously obtain a sufficient burr reduction effect and sufficient mechanical strength and weld strength. The total ash content is 1 at 150 ° C.
5 g of the resin dried for 5 hours is placed in a crucible, and the residue weight obtained by burning at 540 ° C. for 6 hours is measured, and the resin after drying (5 g) is dried.
The ratio of the weight of the residue to the weight of the residue was calculated. Typical examples of the PPS resin satisfying the above conditions include M2888 and M2588 manufactured by Toray Industries, Inc.

The PPS resin used as the component (B) in the present invention, unlike the component (A), must have a number average molecular weight of 3,000 to 6,000 and have substantially no crosslinked structure. . When the number average molecular weight is less than 3,000, it is difficult to obtain sufficient mechanical strength and weld strength. The number average molecular weight is 6000
When the ratio exceeds, it is difficult to obtain excellent fluidity and a sufficient burr reduction effect at the same time.

The method for producing the PPS resin of the present invention is not particularly limited as long as the above-mentioned necessary conditions are satisfied, and is generally known, that is, the method described in JP-B-45-3368 or JP-B-52-12240. And the like. In the present invention, the PPS resin obtained as described above is subjected to various treatments such as washing with an organic solvent, hot water, an aqueous acid solution and the like, and activation with a functional group-containing compound such as an acid anhydride group, an epoxy group and an isocyanate group. It is also possible to use after doing.

The mixing of the PPS resin of the component (A) and the component (B) is more than 5% by weight and less than 50% by weight of the PPS resin of the component (A) and more than 95% by weight of the PPS resin of the component (B). %, Preferably component (A) 2
The content of component (B) is more than 50% by weight and not more than 80% by weight with respect to 0% by weight or more and less than 50% by weight, and more preferably 30 to 49% by weight of component (A) and 51 to 50% by weight of component (A).
70% by weight. If the PPS resin of the component (A) is at least 50% by weight, the fluidity will be low. PPS of component (A)
If the resin content is less than 5% by weight, the mechanical strength and the weld strength are undesirably deteriorated.

The fibrous or non-fibrous reinforcing material (C) in the present invention is a PPS comprising component (A) and component (B) for the purpose of improving the heat resistance and strength of the PPS resin.
0 to 150 parts by weight is blended with respect to 100 parts by weight of the resin.

As such a fiber reinforcing material, glass fiber,
Examples thereof include alumina fibers, silicon carbide fibers, ceramic fibers, asbestos fibers, stone fibers, metal fibers, inorganic fibers such as potassium whisker, and carbon fibers. Examples of the non-fibrous reinforcing material include silicates such as wollastenite, sericite, kaolin, mica, clay, bentonite, asbestos, talc, and alumina silicate, alumina, silicon chloride, magnesium oxide, zirconium oxide, and titanium oxide. Examples include metal compounds, carbonates such as calcium carbonate, magnesium carbonate and dolomite, sulfates such as calcium sulfate and barium sulfate, glass beads, boron nitride, silicon carbide and silica, and these may be hollow.

These reinforcing materials can be used in combination of two or more, and if necessary, can be used after being pretreated with a silane-based or titanium-based coupling agent. Particularly preferred reinforcements are glass fibers and carbon fibers for fibrous reinforcements, and walasteinite, talc and calcium carbonate for non-fibrous reinforcements.

The amount of the reinforcing material (C) is in the range of 0 to 150 parts by weight based on 100 parts by weight of the PPS resin comprising the components (A) and (B). From the balance between the properties and mechanical strength,
A blending amount of the reinforcing material of 100 parts by weight is preferable. If the amount of the reinforcing material is more than 150 parts by weight, the fluidity of the composition is significantly impaired, which is not preferable.

Next, the alkoxysilane compound used as the component (D) in the present invention is an alkoxysilane compound having at least one epoxy group, amino group, ureide group, isocyanate group, hydroxyl group or mercapto group in the molecule. Specifically, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-glycidoxypropylmethyldiethoxysilane, (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N-
(2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldiethoxysilane, N-phenylaminomethyltrimethoxysilane, N -Phenylaminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, γ-ureidopropyltrimethoxysilane, γ- (2-ureidoethyl) aminopropyltrimethoxysilane, dimethoxymethyl-3-piperazinopropylsilane, 3 -Piperazinopropyltrimethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3
-Isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldimethoxysilane, 3-isocyanatopropylmethyldiethoxysilane, 3-isocyanatopropylethyldimethoxysilane, 3-hydroxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxy Examples include silane, 3-mercaptopropyltriethoxysilane, and 3-mercaptomethyldimethoxysilane.

These alkoxysilane compounds can be used alone or in the form of a mixture of two or more. Among the above-mentioned alkoxysilane compounds, a particularly preferred alkoxysilane compound is 3-glycidoxypropyltrimethoxysilane. , N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, γ-ureidopropyltrimethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-hydroxypropyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane And the like.

The amount of the alkoxysilane compound (D) used in the present invention is 0.1 to 5 parts by weight, preferably 0.3 to 3 parts by weight, per 100 parts by weight of the PPS resin.
Parts by weight. If the addition amount is less than 0.1 parts by weight, the effect of improving mechanical strength and weld strength is not sufficiently exhibited,
If the amount exceeds 5 parts by weight, the fluidity and mechanical strength of the composition are impaired, which is not preferable.

The PPS resin composition of the present invention contains a releasing agent, an antioxidant, a heat stabilizer, a lubricant, a crystal nucleating agent, a UV inhibitor, a coloring agent, a flame retardant as long as the effects of the present invention are not impaired. Conventional additives such as and small amounts of other polymers can be added. For example, examples of the release agent include polyolefins such as polyethylene and polypropylene, montanic acid waxes, and metal soaps such as lithium stearate and aluminum stearate. Also,
Examples of the crystal nucleating agent include a polyether-terketone resin, a nylon resin, and talc.

The method for preparing the PPS resin composition of the present invention is not particularly limited, but the mixture of the raw materials is usually known in the art such as a single-screw or twin-screw extruder, a Banbury mixer, a kneader, and a mixin roll. 280 to 3
A typical example is a method of kneading at a temperature of 80 ° C., and the order of mixing the raw materials is not particularly limited. In addition, as for the small amount additive component, other components can be added before kneading after kneading and pelletizing other components by the above method or the like.

The PPS resin composition obtained according to the present invention is a resin composition which is less likely to generate burrs and has excellent thin-wall fluidity and excellent molding processability. It is useful for applications such as connectors, electronic sealing parts and coil sealing parts.

[0024]

The present invention will be described in more detail with reference to the following examples.

The number average molecular weight, weld strength, molding minimum pressure and burr length described in the examples and comparative examples were evaluated and measured according to the following methods.

Number average molecular weight: The number average molecular weight was measured using a gel permeation chromatograph manufactured by Waters, according to the method disclosed in the Journal of Polymers, Vol. 44 (1987), February, pp. 139-141.

Measurement of weld strength: AST having gates at both ends and a weld line near the center of the test piece
M4 dumbbell pieces were molded using an injection molding machine with a mold clamping force of 20 tons at a cylinder temperature of 320 ° C. and a mold temperature of 135 ° C., and the tensile strength was measured at a strain rate of 5 mm / min and a fulcrum distance of 64 mm. Was performed.

Evaluation of minimum molding pressure: The minimum injection pressure required to prevent poor filling during the injection molding of the flat molded product was defined as the minimum molding pressure. The lower the lower molding pressure, the better the fluidity.

Measurement of the burr length: The length of the burr generated in the degassing gap of the above flat plate was measured. The shorter the burr length, the better the burr characteristics.

Reference Example 1 In this Example and Comparative Examples, as the PPS resin of the component (A), M2888 (PPS-1) and M25 manufactured by Toray Industries, Ltd., which are PPS resins having substantially no crosslinked structure.
88 (PPS-2) was used. The PPS resin had a number average molecular weight of 10,000 and 9000, respectively, and the total ash content was 0.07 and 0.08% by weight, respectively. Further, the ratio Mw / Mn of the number average molecular weight (Mn) to the weight average molecular weight (Mw) of M2888 (PPS-1) was 4.99.

Reference Example 2 (Polymerization of PPS) A 30% aqueous solution of sodium hydrosulfide 4.6 was placed in an autoclave.
7 kg (25 mol of sodium hydrosulfide), 2.00 kg of 50% sodium hydroxide (25 mol of sodium hydroxide) and 8 kg of N-methyl-2-pyrrolidone (hereinafter abbreviated as NMP) are charged and gradually stirred to 205 ° C. while stirring. The temperature was raised, and 4.1 l of distillate containing 3.8 kg of water was removed. 3.75 k of 1,4-dichlorobenzene was added to the residual mixture.
g (25.5 mol) and 2 kg of NMP to add
The mixture was heated at 0 ° C. for 1 hour and further at 260 ° C. for 30 minutes. The reaction product was washed five times with warm water and dried under reduced pressure at 80 ° C. for 24 hours to obtain a powder having a number average molecular weight of 3,700 and having substantially no crosslinked structure (PPS-3). The PPS resin was used in Examples and Comparative Examples.

Reference Example 3 (Polymerization of PPS) A 30% aqueous sodium hydrosulfide solution 4.6 was placed in an autoclave.
7 kg, 2.00 kg of 50% sodium hydroxide and 8 kg of NMP were charged, and the temperature was gradually raised to 205 ° C. while stirring to remove 4.1 l of distillate containing 3.8 kg of water. 3.75 k of 1,4-dichlorobenzene was added to the residual mixture.
g and 2 kg of NMP were added, and the mixture was heated at 230 ° C. for 1 hour and further at 260 ° C. for 2 hours. The reaction product was washed five times with warm water and dried under reduced pressure at 80 ° C. for 24 hours to obtain a powder having a number average molecular weight of 5,400 and having substantially no crosslinked structure (PPS-4). The PPS resin was used in Examples and Comparative Examples.

Reference Example 4 As a PPS resin, ASTM D1238-86 (31
M having a crosslinked structure having a melt flow rate value of 70% at a retention time of 5 minutes at a retention time of 15 minutes specified at 5.5 ° C. and a load of 5000 g) manufactured by Toray Industries, Inc.
2100 (PPS-5) was used. The ratio Mw / Mn of the number average molecular weight (Mn) to the weight average molecular weight of the PPS resin was 50, and the melt viscosity (300 ° C., 200 / sec) was 300 poise.

Example 1 PPS-1, PPS-3, 3-isocyanatopropyltrimethoxysilane and glass fiber were dry-blended in the proportions shown in Table 1, and then set to a screw condition of 320 ° C. The mixture was melt-kneaded and pelletized.
Using the obtained pellets, the above-mentioned ASTM No. 4 dumbbell pieces and the flat plate molded product were molded under the conditions of a cylinder temperature of 320 ° C. and a mold temperature of 135 ° C. using an injection molding machine having a mold clamping force of 20 tons.

Table 2 shows the weld strength, minimum molding pressure, and burr length measured for the obtained test pieces.

Comparative Example 1 Dry blending, melt kneading, pelletizing, molding, and evaluation of physical properties were carried out in the same manner as in Example 1 except that PPS-3 was not used. The results are also shown in Table 2.

When a low-molecular-weight linear PPS resin was not blended, the fluidity was low, and no sufficient burr reduction effect was obtained.

Comparative Example 2 Dry blending, melt kneading, pelletizing, molding, and evaluation of physical properties were performed at the ratios shown in Table 1 in the same manner as in Example 1 except that PPS-1 was not used. The results are also shown in Table 2.

When a high-molecular-weight linear PPS resin was not blended, sufficient mechanical strength could not be obtained.

Comparative Example 3 Dry blending, melt kneading, and mixing at the ratios shown in Table 1 were carried out in the same manner as in Example 1 except that no silane compound was added.
Pelletizing, molding, and physical property evaluation were performed. Table 2 shows the results.

It can be seen that when no silane compound is added, a sufficient mechanical strength and a deburring effect cannot be obtained.

Comparative Example 4 Dry blending, melt kneading and pelletizing were performed in the same manner as in Example 1 except that PPS-1, PPS-5, glass fiber and 3-mercaptopropyltrimethoxysilane were blended in the proportions shown in Table 1. , Molding and physical properties were evaluated. Table 2 shows the results.

Examples 2 to 14 Dry blending, melt kneading, pelletizing, pelletizing, and the like shown in Table 1 were carried out in the same manner as in Example 1 by changing the types and blending ratios of the PPS resin, reinforcing material, and alkoxysilane compound used. Molding and physical property evaluation were performed. Table 2 shows the results.

Each of the resin compositions obtained here was excellent in strength, thin-wall fluidity, and low burr and of high practical value.

[0045]

[Table 1]

[0046]

[Table 2]

[0047]

The polyphenylene sulfide resin composition of the present invention has less burrs generated during molding and is excellent in thin-wall fluidity, and is particularly useful for applications such as injection molded connectors, electronic sealing parts, and coil sealing parts. It is.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI H01B 3/30 H01B 3/30 J H01F 41/12 H01F 41/12 B H01L 23/29 H01R 13/46 Z 23/31 H01L 23 / 30 R H01R 13/46 (56) References JP-A-62-197451 (JP, A) JP-A-64-89208 (JP, A) JP-A-64-87659 (JP, A) JP-A-63-19759 225656 (JP, A) JP-A-61-87752 (JP, A) JP-A-3-12453 (JP, A) JP-A-3-43452 (JP, A) JP-A-3-255162 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 81/00-81/10 CA (STN) REGISTRY (STN)

Claims (4)

(57) [Claims] (A) A substantially crosslinked structure having a number average molecular weight of 7000 to 15000 and a total ash content of 0.3% by weight or less, determined by gel permeation chromatography using 1-chloronaphthalene as a solvent. 95% by weight or more and less than 50% by weight of a polyphenylene sulfide resin having no, and (B) more than 50% by weight of a polyphenylene sulfide resin having a number-average molecular weight of 3000 to 6000 and having substantially no crosslinked structure 95 (C) at least one kind of fibrous or non-fibrous reinforcing material (0-15) per 100 parts by weight of the polyphenylene sulfide resin mixture consisting of
0 parts by weight, (D) epoxy group, amino group, ureide group,
A polyphenylene sulfide resin composition obtained by melt-kneading 0.1 to 5 parts by weight of an alkoxysilane compound having at least one functional group selected from an isocyanate group, a hydroxyl group and a mercapto group. 2. A polyphenylene sulfide resin composition for a connector comprising the polyphenylene sulfide resin composition according to claim 1. 3. A polyphenylene sulfide resin composition for electronic sealing parts, comprising the polyphenylene sulfide resin composition according to claim 1. 4. A polyphenylene sulfide resin composition for coil sealing parts, comprising the polyphenylene sulfide resin composition according to claim 1.