JPH10237301A - Polyphenylene sulfide resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject composition useful for a use requiring low burring property and fluidity through a thin cross section, such as a connector, an electronic sealing member or a coil sealing member by compounding a reinforcing material and a highly polymerized fluorine-based polymer with a polyphenylene sulfide resin. SOLUTION: This composition useful for an injection-molded product such as a connector or a sealing member is obtained by compounding (A) 100 pts.wt. of a polyphenylene sulfide resin with (B) 0-400 pts.wt., preferably 40-200 pts.wt. of a reinforcing material of a fibrous reinforcing material such as glass fibers or carbon fibers, or a non-fibers reinforcing material such as wollastonite, talc or calcium carbonate, (C) 0.1-5 pts.wt., preferably 0.3-3 pts.wt. of a fluorine-based polymer such as polytetrafluoroethylene having >=1×10<6> , preferably 4×10<6> -3×10<8> number-average molecular weight and preferably further (D) 0.1-5 pts.wt. of an organic silane compound.

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 which is useful in applications requiring low burr and thin fluidity, such as connectors or sealing parts such as electronic sealing parts and coil sealing parts. It relates to a composition.

[0002]

2. Description of the Related Art Polyphenylene sulfide resin (hereinafter referred to as P
PS resin) is suitable for engineering plastics, such as excellent heat resistance, flame retardancy, rigidity, and electrical insulation. Therefore, various electric parts, machine parts, and automobiles are mainly used for injection molding. Used for parts and other applications.

[0003] However, the use of PPS resin is severely restricted in burrs, for example, in parts sealing applications such as connector or electronic parts sealing and coil sealing.

[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. 3-1).
97562).

[0005]

However, conventional burr reduction techniques such as addition of a highly cross-linked PPS resin or addition of a silane compound have the problems of reducing the fluidity of the composition as a whole, In particular, in the application of injection molding of thin precision parts, there have been problems such as poor filling and gas burning.

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, and as a result, a specific molecular weight By adding a fluorine-based polymer such as polytetrafluoroethylene (hereinafter abbreviated as PTFE) to a PPS resin, it has been found that a high-performance PPS resin composition that satisfies all of the above-mentioned desired properties can be obtained. Reached the present invention.

[0007]

That is, the present invention provides: (A) 100 parts by weight of polyphenylene sulfide resin, (B) 0 to 400 parts by weight of reinforcing material, and (C) fluoropolymer having a number average molecular weight (Mn) of 1,000,000 or more.
1. a polyphenylene sulfide resin composition containing 1 to 5 parts by weight; The polyphenylene sulfide resin composition according to claim 1, wherein (C) the fluorine-based polymer is polytetrafluoroethylene.

[0008] 3. Further, (D) 0.1 parts by weight of the organosilane compound is added to 100 parts by weight of the polyphenylene sulfide resin.
3. The polyphenylene sulfide resin composition according to the above 1 or 2, which is blended in an amount of from 5 to 5 parts by weight. 4. The polyphenylene sulfide resin composition according to any one of the above 1 to 3, wherein the polyphenylene sulfide resin composition is for a connector molded product; 5. The polyphenylene sulfide resin composition according to any one of the above items 1 to 3, wherein the polyphenylene sulfide resin composition is for sealing electronic parts. 6. A molded product for a connector obtained by injection molding the polyphenylene sulfide resin composition according to any one of the above items 1 to 4, and A molded article for a sealing part obtained by injection molding the polyphenylene sulfide resin composition according to any one of the above 1 to 3 or 5.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The PPS resin used in the present invention is a polymer having a repeating unit represented by the structural formula (1),

Embedded image 70 mol% of the repeating unit represented by the above structural formula (1)
From the viewpoint of heat resistance, a polymer containing 90 mol% or more is particularly preferable. Further, the PPS resin can constitute less than 30 mol% of the repeating unit with a repeating unit having the following structure.

[0010]

Embedded image

The melt viscosity of the PPS resin used in the present invention is not particularly limited as long as melt kneading is possible.
5 to 2000 Pa · s (320 ° C, shear rate 1000 sec
c ^-1 ) is used, and a range of 10 to 300 Pa.s is more preferable.

The production can be carried out by a generally known method, for example, the method described in JP-B-45-3368 or the method described in JP-B-52-12240. In the present invention, the PPS resin obtained as described above is crosslinked / polymerized by heating in air, heat-treated under an atmosphere of an inert gas such as nitrogen or under reduced pressure, or with an organic solvent, hot water, an acid aqueous solution or the like. It is also possible to use after washing. When washing with an organic solvent, the organic solvent to be used is not particularly limited as long as it does not have an action of decomposing PPS. For example, N-methylpyrrolidone, dimethylformaldehyde, dimethylacetamide, 1,3-dimethylimidazolidinone , Hexamethylphosphorasamide, nitrogen-containing polar solvents such as piperazinones, sulfoxide / sulfone solvents such as dimethyl sulfoxide, dimethyl sulfone, sulfolane, ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, acetophenone, dimethyl ether, dipropyl ether , Dioxane, ether solvents such as tetrahydrofuran, chloroform, methylene chloride, trichloroethylene, ethylene chloride, perchlorethylene, monochloroethane, dichloroethane,
Halogen-based solvents such as tetrachloroethane, perchloreethane, and chlorobenzene; alcohol and phenol-based solvents such as methanol, ethanol, propanol, butanol, pentanol, ethylene glycol, propylene glycol, phenol, cresol, polyethylene glycol, and polypropylene glycol; And aromatic hydrocarbon solvents such as benzene, toluene and xylene. There is no particular limitation on the washing temperature,
Usually, room temperature to about 300 ° C. is selected. When washing with an aqueous acid solution, the acid used is not particularly limited as long as it does not have the action of decomposing PPS. For example, acetic acid,
Examples include hydrochloric acid, sulfuric acid, phosphoric acid, silicic acid, carbonic acid and propyl acid. It is also possible to use the product after performing various treatments such as activation with a compound containing a functional group such as an acid anhydride group, an epoxy group, and an isocyanate group.

The component (B) reinforcing material of the present invention is used for improving the heat resistance and strength of the PPS resin.
It is blended at a ratio of 0 to 400 parts by weight with respect to 100 parts by weight of the PS resin, and may be either fibrous or non-fibrous, or may be used in combination.

Examples of the fibrous reinforcing material include glass fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, stone fiber, metal fiber, inorganic fiber such as potassium titanate whisker, and carbon fiber. 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. Metal compounds, carbonates such as calcium carbonate, magnesium carbonate, dolomite,
Examples thereof include sulfates such as calcium sulfate and barium sulfate, glass beads, boron nitride, silicon carbide, and silica, which 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 wollastenite, talc and calcium carbonate for non-fibrous reinforcements.

The amount of the reinforcing material (B) is in the range of 0 to 400 parts by weight based on 100 parts by weight of the component (A) PPS resin. From the viewpoint of balance, the amount is preferably 40 parts by weight or more, and particularly preferably 40 to 200 parts by weight of the reinforcing material. If the compounding amount of the reinforcing material exceeds 400 parts by weight, the fluidity of the composition is significantly impaired, which is not preferable.

The component (C) fluorine-based polymer used in the present invention is a polymer containing a fluorine atom in the molecule.

The number average molecular weight (Mn) of the fluoropolymer used in the present invention is 1,000,000 or more, preferably 40
It is more than 100,000. There is no particular upper limit, but usually 5 × 1
0 ⁸ or less, particularly preferably 3 × 10 ⁸ or less. Such a number average molecular weight can be determined by a known method.

The fluoropolymer used in the present invention is PPS
It is preferable that the resin does not substantially melt at the molding temperature of the resin.

As such a fluorine-based polymer, polytetrafluoroethylene (PTFE) is exemplified.

It is known that the number average molecular weight (Mn) of PTFE satisfies the following relational expression with the specific gravity d.

[0022]

## EQU1 ## d = −0.0579 log (Mn) +2.6113

When PTFE is used as the fluorine-based polymer, its number average molecular weight can be determined by this relational expression.

The production method is not particularly limited, and it can be produced by generally known emulsion polymerization or suspension polymerization.

Examples of commercially available PTFE include "Teflon 6J" (manufactured by Dupont), "Polyflon F201" (manufactured by Daikin Industries), and "Hostaflon TF1620" (manufactured by Hoechst).

The compounding amount of PTFE is 0.1 to 5 parts by weight, preferably 0.3 to 3 parts by weight based on 100 parts by weight of the component (A) PPS resin. If the amount is less than 0.1 part by weight, the desired effect of improving low burr may not be sufficiently exhibited, and if it exceeds 5 parts by weight, the fluidity and mechanical strength of the composition may be impaired.

Next, the organosilane 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, specifically, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2- ( 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-hydroxypropyltrimethoxy Examples include silane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and 3-mercaptomethyldimethoxysilane.

The amount of the organic silane compound (D) is usually in the range of 100 parts by weight of the component (A) PPS resin.
It is 0.1 to 5 parts by weight, preferably 0.3 to 3 parts by weight. Preferred organic silane compounds include one or more selected from epoxy group-containing alkoxysilane compounds, amino group-containing alkoxysilane compounds, ureido group-containing alkoxysilane compounds, isocyanate group-containing alkoxysilane compounds, and mercapto group-containing alkoxysilane compounds. Can be

The PPS resin composition of the present invention contains a releasing agent, an antioxidant, a heat stabilizer, a lubricant, a crystal nucleating agent, an ultraviolet absorber, a coloring agent, a flame retardant, etc. as long as the effects of the present invention are not impaired. The usual additives and small amounts of other polymers can be added. For example, as the release agent, polyethylene,
Examples thereof include polyolefins such as polypropylene, montanic acid waxes, metal soaps such as lithium stearate and aluminum stearate, and polycondensates of ethylenediamine / stearic acid / sebacic acid. As a nucleating agent, polyether ether ketone resin,
Talc and the like can be mentioned.

The method for producing the PPS resin composition of the present invention is not particularly limited, but the mixture of the raw materials is supplied to a generally known melt mixer such as a single-screw or twin-screw extruder, a Banbury mixer, a kneader and a mixing roll. 280
A typical example is a method of melting and kneading at a temperature of 380 ° C. 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-described method or the like.

The resin composition of the present invention is generally molded by a known thermoplastic resin molding method such as injection molding, extrusion molding, blow molding, transfer molding, and vacuum molding. In particular, injection molding is preferred.

The PPS resin composition obtained according to the present invention is a resin composition having less burrs and excellent flowability and excellent molding processability.・ Useful for office electrical product parts, machine related parts, optical equipment / precision machine related parts, automobile / vehicle related parts, and various other uses. Among them, it is particularly suitable for applications requiring low burr and thin fluidity, and specifically includes connectors, motors, coil sealing parts such as coils, sealing parts such as electronic sealing parts, and the like. .

[0033]

The present invention will be described in more detail with reference to the following examples. The weld strength, the minimum molding pressure, the loss on heating and the burr length described in the examples and comparative examples were evaluated and measured according to the following methods.

(1) Measurement of Weld Strength An ASTM No. 4 dumbbell piece having gates at both ends and a weld line near the center of the test piece was placed at a cylinder temperature of 320 ° C. using an injection molding machine having a mold clamping force of 75 tons. Molding was performed at a mold temperature of 135 ° C., and tensile strength was measured at a strain rate of 5 mm / min and a distance between fulcrums of 64 mm.

(2) Evaluation of molding lower limit pressure In injection molding of the above flat molded article, the minimum injection pressure necessary to prevent poor filling was defined as the molding lower limit pressure. The lower the minimum molding pressure, the better the fluidity.

(3) Measurement of loss on heating 10 g of a pellet of the resin composition is placed in an aluminum cup, and
Predry for 1 hour in an atmosphere of 50 ° C. The weight of the pellet is measured, and after treatment in an atmosphere at 320 ° C. for 2 hours, the weight of the pellet is measured again. The weight loss by heating is expressed as a percentage by dividing the weight loss by the treatment at 320 ° C. by the weight of the pellet before the treatment. It can be said that the resin composition having a smaller loss on heating has a smaller outgas during molding.

(4) Measurement of Burr Length An ASTM No. 4 dumbbell piece having a gate at one end and a gap for venting at the other end was measured at a resin temperature of 290
Injection molding was performed under the conditions of 330 ° C. and a mold temperature of 120 to 150 ° C., and the length of a burr generated in a degassing gap of the obtained dumbbell piece was measured. The shorter the burr length, the better the burr characteristics.

Example 1 PPS resin (L2120 manufactured by Toray), PTFE (“Teflon 6J” manufactured by DuPont, number average molecular weight: about 8,000,000) and glass fiber were dry-blended at the ratios shown in Table 1, and then subjected to a temperature condition of 320 ° C. The mixture was melt-kneaded with a screw extruder set as described above and pelletized. Using the obtained pellets, using an injection molding machine with a mold clamping force of 75 tons, the above-mentioned AST under the conditions of a cylinder temperature of 320 ° C. and a mold temperature of 135 ° C.
Molding of M4 dumbbell pieces was performed.

Table 1 shows the measured weld strength, minimum molding pressure, loss on heating, and burr length of the obtained pellets and 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 PTFE was not used. Table 1 shows the results.

It can be seen that the burr reduction effect cannot be obtained when PTFE is not blended.

Comparative Example 2 Dry blending, melt kneading, and mixing were performed in the proportions shown in Table 1 in the same manner as in Example 1 except that "Lubron L5" (number average molecular weight: about 200,000) manufactured by Daikin Industries, Ltd. was used as the PTFE. Pelletizing, molding, and physical property evaluation were performed. Table 1 shows the results.

When PTFE having a molecular weight of 1,000,000 or less was used, no burr reduction effect was obtained.

Comparative Example 3 Dry blending, melt kneading, pelletizing, molding, and evaluation of physical properties were performed in the same manner as in Example 1 except that PTFE ("Teflon 6J") was blended at the ratio shown in Table 1. Table 1 shows the results.

Although excellent in low burr, the weld strength was low and the minimum molding pressure was high.

Example 2 PPS resin, glass fiber, PTFE and 2- (3,4-
Dry blending, melt kneading, pelletizing, molding, and evaluation of physical properties were performed in the same manner as in Example 1 except that (epoxycyclohexyl) ethyltrimethoxysilane was blended in the ratio shown in Table 1. Table 1 shows the results.

The obtained resin composition was excellent in low burr property, high weld strength and good fluidity.

Comparative Example 4 Dry blending and melt kneading were carried out in the same manner as in Example 1 except that the PPS resin, glass fiber and 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane were blended in the proportions shown in Table 1. , Pelletizing, molding, and physical properties were evaluated. Table 1 shows the results.

Although the low burr property and the weld strength were excellent, the molding lower limit pressure was high and the loss on heating was large.

Example 3 "Hostaflon TF162" manufactured by Hoechst was used as the PTFE.
Using "0" (number average molecular weight of about 10,000,000), dry blending, melt kneading, pelletizing, molding, and evaluation of physical properties were performed in the same manner as in Example 1 at the ratios shown in Table 1. Table 1 shows the results.

The obtained resin composition was excellent in low burr, high weld strength and good fluidity.

[0052]

[Table 1]

[0053]

Industrial Applicability 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 connectors formed by injection molding, electronically sealed parts, coil sealed parts and the like. Useful for sealing parts.

Claims (7)

[Claims] 1. A polyphenylene sulfide resin (A)
(B) 0 to 400 parts by weight of reinforcing material with respect to 0 parts by weight,
(C) A polyphenylene sulfide resin composition comprising 0.1 to 5 parts by weight of a fluoropolymer having a number average molecular weight (Mn) of 1,000,000 or more. 2. The polyphenylene sulfide resin composition according to claim 1, wherein (C) the fluoropolymer is polytetrafluoroethylene. 3. An organic silane compound (D) in an amount of 0.1 to 5 parts by weight per 100 parts by weight of polyphenylene sulfide resin.
3. The polyphenylene sulfide resin composition according to claim 1, which is blended by weight. 4. The polyphenylene sulfide resin composition according to claim 1, wherein the polyphenylene sulfide resin composition is for a connector molded article. 5. The polyphenylene sulfide resin composition according to claim 1, wherein the polyphenylene sulfide resin composition is for sealing electronic parts. 6. A molded article for a connector obtained by injection molding the polyphenylene sulfide resin composition according to claim 1. 7. A molded article for a sealing part obtained by injection molding the polyphenylene sulfide resin composition according to claim 1.