JPH0616935A - Polyphenylene sulfide resin composition - Google Patents

Abstract

PURPOSE:To obtain a polyphenylene sulfide resin composition useful as precision molded article, etc., having excellent fluidity and mold release characteristics, showing low barrier properties by blending specific amounts of a specific polyphenylene sulfide resin, a mold release agent such as polyethylene wax and an inorganic filler. CONSTITUTION:The composition comprises (A) 100 pts.wt. polyphenylene sulfide resin having 50-150g/10 minutes melt flow rate measured under a condition with an orifice having 0.0825 + or - 0.0002 inch, 1.250+ or -0.001 inch orifice length under 1,270g load at 600+ or -1 deg.F and >=1wt.% low-molecular weight component extracted in a suspension state at normal temperature by using methylene chloride, (B) 0.1-3 pts.wt. mold release agent composed of polyethylene wax, ethylene-propylene copolymer wax, a compound of formula I [X is CO-R (R is 6-24C alkyl or alkenyl)] or a compound of formula II (n is l-3) and (C) 20-300 pts.wt. filler such as glass fibers, talc or glass powder.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polyphenylene sulfide resin composition having improved injection molding processability,
It provides materials suitable for precision molded product applications such as electric / electronic parts, automobiles, and mechanical parts.

[0002]

2. Description of the Related Art Polyphenylene sulfide resin is usually provided as a glass fiber reinforced compound, and due to its excellent heat resistance, flame retardancy, chemical resistance and dimensional stability,
It is widely used for electric / electronic equipment parts materials, automobiles, machine parts materials and precision equipment parts materials.

Parts in these fields are made lighter (thinner,
(Reduction, reduction), precision, complicated shapes, etc. are progressing, and along with this, demands for improvement in strength, heat resistance, and moldability of materials are also increasing.

[0004]

As the reinforced polyphenylene sulfide resin used in these applications, a linear type polyphenylene sulfide resin having improved strength and toughness has been used. However, although the linear polyphenylene sulfide resin has excellent mechanical properties, it has a drawback in that burrs are likely to occur during molding.

An improved linear type polyphenylene sulfide reinforced resin has been developed and put to practical use in order to suppress the generation of burrs, but this resin has a poor fluidity and therefore has a limited range of applications for molded articles. ing. Therefore, it has been desired to develop a polyphenylene sulfide resin composition having excellent fluidity, low burr, and having no problem in mold releasability for obtaining a molded product having a complicated shape.

[0006]

Means for Solving the Problems The present inventors have conducted various studies to improve the above-mentioned problems and obtain a resin composition having good fluidity, low burr, and good mold releasability. It has been found that this object can be achieved by combining a low-viscosity polyphenylene sulfide resin, a specific silane compound, glass fiber and the like and a specific release agent, and completed the present invention.

That is, the gist of the present invention is (A) an orifice having an orifice diameter of 0.0825 ± 0.0002 inches and an orifice length of 1.250 ± 0.001 inches, a load of 1270 g, and a resin temperature of 600 ± 1 ° F. 100 parts by weight of a polyphenylene sulfide resin having a melt flow rate measured under the conditions of 50 to 150 g / 10 minutes and a low molecular weight component suspended and extracted with methylene chloride at room temperature of 1% by weight or less; B) at least one silane compound selected from the group consisting of epoxyalkoxysilanes and aminoalkoxysilanes;
2 parts by weight, (C) polyethylene wax, ethylene-propylene copolymer wax, at least one releasing agent selected from the compound represented by the following formula (1) and the compound represented by the following formula (2); 0 1-3 parts by weight

[0008]

[Chemical 7]

[In the formula (1), X is —CO—R (R represents an alkyl group or an alkenyl group having 6 to 24 carbon atoms)]

[0010]

[Chemical 8]

[In the formula (2), X is the same as above. n is 1 to 3
Is. (D) Inorganic filler; a polyphenylene sulfide resin composition comprising 20 to 300 parts by weight and a method for producing the same.

The polyphenylene sulfide resin used in the present invention is a substantially linear thermoplastic polymer represented by the following structural formula, which is usually produced by polycondensation of sodium sulfide and p-dichlorobenzene. Specifically, it is manufactured by the manufacturing method shown in Japanese Patent Publication No. 52-12240.

[0013]

[Chemical 9]

The polyphenylene sulfide resin used in the present invention has a lower molecular weight than that shown in Japanese Patent Publication No. 52-12240, and it is necessary to make the polyphenylene sulfide resin satisfying the following characteristics depending on the production conditions selected. . That is, the polyphenylene sulfide resin suitable for the present invention has an orifice diameter of 0.0825 ±
0.0002 inch, orifice length 1.250 ± 0.0
With an orifice that is 01 inch, the load is 1270g,
The melt flow rate measured under the condition of the resin temperature of 600 ± 1 ° F. is 50 to 150 g / 10 min, preferably 50 to 150 g / 10 min.
120 g / 10 minutes, more preferably 60-90 g / 10
And a low molecular weight component suspended and extracted with methylene chloride is 1% by weight or less, preferably 0.3.
It is less than or equal to wt. If the amount of the low molecular weight component is large, the fluidity is apparently good, but it is not preferable because it causes gas generation during molding, deteriorates the filling of details, and causes gas burn and mold corrosion.

The release agent which is the component (B) of the composition of the present invention is an essential component for releasing the molded product from the mold during the injection molding process. The mold release agent is an essential component especially when the molded product is complicated and has a large mold release resistance, but as a harmful effect of the addition of the mold release agent, there is generation of thermal decomposition gas due to insufficient heat resistance against the molding processing temperature. This generated gas has a bad appearance,
It causes burn due to high temperature due to compression heat insulation at the flow end. In addition, this may cause defective filling of details.
In addition, it accumulates in the welded part of the molded product, causing defective welding and gas burning, which impairs the strength of the product. A polyethylene wax or an ethylene-propylene copolymer wax is useful as a mold release agent having good heat resistance that does not cause these harmful effects as much as possible. Those waxes having a low acid value are suitable, and those having an acid value of 2 or less, preferably 1 or less are suitable. The molecular weight of these waxes is 20.
00 to 15000 is preferable. If the molecular weight is lower than this, a large amount of gas is generated, and if the molecular weight is too high, the releasing effect is insufficient.

Further, as a release agent, the following formula (1) or (2)
The compounds shown in 1) are excellent in heat resistance and releasing effect, and can be applied to the composition of the present invention.

[0017]

[Chemical 10]

[In the formula (1), X is -CO-R (R represents an alkyl group or an alkenyl group having 6 to 24 carbon atoms)]

[0019]

[Chemical 11]

[In the formula (2), X is the same as above. n is 1
3, preferably 2. Among the releasing agents represented by the formula (1), those in which R is an alkyl group having 17 carbon atoms are most preferable, and among the releasing agents represented by the formula (2), R is Most preferably has 17 carbon atoms and n is 2.

The amount of the release agent added is 0.1 to 3 parts by weight, preferably 0.2 to 2 parts by weight. As the component (C) inorganic filler in the composition of the present invention, glass fiber, glass flake, glass powder, talc, mica and the like are used, and glass fiber is most preferable. As this glass fiber, a chopped strand which is usually provided for an injection molding compound is used and has a diameter of 3 μ to 2 μm.
0μ, preferably 6μ-13μ, strand length 3mm
From 6 mm is preferable.

The glass fiber is produced by adding a small amount of a silane coupling agent to a urethane resin, an epoxy resin or a mixture thereof, and converging the glass fiber so that the basis weight is from 0.2 wt% to 1 wt%. What is suitable is. Moreover, it is preferable that the glass fibers have a number average fiber length of 150 μ to 400 μ by kneading and crushing at the time of preparing the composition.

Glass fiber is most suitable as an inorganic filler from the viewpoint of improving heat resistance, strength, and moldability of a molded product, and the glass fiber content of the composition is 15 to 5.
It is good to set it to 0 wt%, preferably 20 to 40 wt%. As the inorganic filler of the component (C) used in the composition of the present invention, in addition to the above-mentioned glass fibers, glass powder, glass flakes, talc, mica, etc. described below are preferably used, but other than these glass fibers. It is preferable to use the inorganic filler (1) in combination with glass fiber rather than using it alone.

The effects of the combined use are reduction of molding shrinkage, improvement of warpage of a molded product due to relaxation of glass fiber orientation, and reduction of burrs. Use of an inorganic filler other than glass fiber alone may be insufficient in terms of strength and heat resistance (heat distortion temperature). Of such inorganic fillers other than glass fiber,
What is glass powder? E-glass crushed with an average particle size of 10
It is a powder of about 50 μ or a milled fiber having a fiber length of 30 to 300 μ obtained by crushing glass fibers having a diameter of 3 μ to 13 μ, and includes those which have been previously treated with a silane coupling agent, an epoxy resin or the like as necessary.

The glass flakes are glass flakes having a thickness of 2 to 7 μm and a particle diameter of 0.3 to 3 mm, and include those pretreated with a silane coupling agent or the like. Types of glass include C glass and E glass, but E glass is suitable. As talc (basic magnesium silicate), there are various types of talc depending on the place of production, but those having an average particle size of 2 to 20 μ which are crushed and refined and classified for plastics regardless of the place of production are suitable.

Suitable mica is muscovite, phlogopite or the like, and the powder having a flake diameter average of 20 μm to 1500 μm prepared for plastic reinforcement is suitable. The amount of these inorganic fillers used is 20 to 300 parts, preferably 30 to 150 parts, relative to 100 parts by weight of the polyphenylene sulfide resin. When glass fibers and other inorganic fillers are used in combination, the amount of the inorganic material to the glass fibers is The proportion of the filler is preferably about 10 wt% to 50 wt%.
When the glass fiber and the above-mentioned other inorganic filler are used in combination, 30 to 80 parts by weight of the glass fiber and 5 to 50 parts by weight of the other inorganic filler are mixed with 100 parts by weight of the polyphenylene sulfide resin. Preferably.

The inorganic filler used in combination with the glass fiber is crushed to a size of about 30 μ or less when kneading and preparing the composition of the present invention. For milled fiber, the length is about 150
Let μ. The polyphenylene sulfide resin composition of the present invention is best manufactured by melt-kneading with a kneading extruder for preparing a plastic composition, preferably by melt-kneading at 280 to 400 ° C. for 1 to 10 minutes. is there. The extruder is preferably a single-screw extruder or a twin-screw extruder equipped with a constant amount of resin and a constant amount of glass fiber. Further, it is preferable to control the cylinder temperature of the extruder within the range of 280 to 330 ° C.

The kneading and extruding are carried out by the processes of weighing, mixing, feeding, melt-kneading and pelletizing raw materials.
When producing the composition of the present invention, it is preferable to use a specific silane compound (D) in addition to the above-mentioned components. The silane compound used in the composition of the present invention is one or more selected from the group consisting of epoxyalkoxysilane and aminoalkoxysilane.
It is preferable to avoid using the epoxyalkoxysilane and the aminoalkoxysilane together because the epoxy group in the epoxyalkoxysilane reacts with the amino group in the aminoalkoxysilane.

The epoxyalkoxysilane is preferably γ-glycidoxypropyltrimethoxysilane,
γ-glycidoxytriethoxysilane, β- (3,4-
Epoxycyclohexyl) ethyltrimethoxysilane,
β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and the aminoalkoxysilane preferably includes γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and the like. The epoxy silane and amino silane described above can also be used.

The amount of component (D) used is 0.1 to 3 parts by weight, preferably 0.3 to 2.0 parts by weight. If the amount used is less than this range, the desired low burr property does not appear, and if it is too large, the thickening is too great and good flowability is impaired. This silane compound is one that reacts with an inorganic filler such as polyphenylene sulfide resin and glass fiber,
Usually, after the composition is prepared, it is not substantially present in the form of the silane compound itself.

Further, the silane compound not consumed in such a reaction is substantially removed and does not remain. In preparing the composition of the present invention, a composition having excellent strength can be obtained because the glass fiber length can be increased by supplying the glass fiber into the molten resin, as compared with the method of mixing and kneading all the raw materials all at once.

First, a polyphenylene sulfide resin is mixed with a silane compound, a release agent, a filler and the like (colorant, heat stabilizer, etc.) with a Henschel mixer, a tumbler or the like. Then, the mixture was quantitatively supplied to the extruder, melt-kneaded,
Glass fiber is supplied and kneaded from the middle of the cylinder. The kneaded mixture is degassed by a vacuum vent and then extruded from a die to obtain the present composition in the form of cooling, cutting and pellets.

The silane compound (liquid) is preliminarily uniformly dispersed in the polyphenylene sulfide resin (powder), or is supplied from the cylinder supply port so as to have a predetermined ratio by a liquid quantitative feeder. It is preferable that the release agent, the inorganic filler, and the like are uniformly mixed and supplied with polyphenylene sulfide. The composition of the present invention thus obtained is a material having excellent moldability and meeting the intended purpose. Therefore, various precision parts (eg, IC connectors, electronic parts such as clay)
Suitable for

[0034]

EXAMPLES The present invention will now be described in more detail with reference to examples, but the present invention is not limited to these without departing from the gist thereof. <Description of Materials Used> (1) Polyphenylene sulfide resin (PPS) The following polyphenylene sulfide resin was obtained according to the method described in JP-B-52-12240.

That is, sodium sulfide and p-dichlorobenzene are mixed in the presence of an alkali metal carboxylate (lithium acetate or sodium acetate) as a solvent (N-methyl-
2-pyrrolidone) Medium temperature 240 to 270 ° C., time 1 to 4
Polymerization was carried out for a period of time, and after the polymerization reaction was completed, the product was washed with water to remove the generated salt and the like and then dried to obtain the following PPS. By appropriately selecting the polymerization temperature and time, PPS having a desired melt flow rate can be obtained.

[0036]

[Table 1]

(2) Silane compound The following compounds were used as silane compounds.

A1; γ-aminopropyltriethoxysilane E1; β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane E2; γ-glycidoxypropyltrimethoxysilane

(3) Release agent R-1; High-density polyethylene wax (molecular weight 4000, acid value 1.0 or less) R-2; 〃 〃 (〃 8000, 〃 〃) R-3; the following formula (3) Compound represented by the formula R-4; a compound represented by the following formula (4)

[0040]

[Chemical 12]

[0041]

[Chemical 13]

(4) Glass Fiber Glass Fiber J: Wire diameter 13 μ, cut length 3 mm, epoxy-urethane type binder resin 0.8% converged product. 〃 K; Wire diameter 10μ, Cut length 3mm, Epoxy-urethane type binder resin 0.4% converged product. (Note that J and K both contain about 10% of aminosilane coupling agent in the binder resin.)

(5) Filler F1; Milled fiber having a diameter of 9 μ and fiber length of 70 μ F2; Glass powder having an average of 20 μ obtained by crushing E glass marble F3; Thickness 4 μ, particle diameter 600 μ: Urethane-epoxy binder 0.6 % Treated glass flake F4; 1% urethane epoxy with talc having an average particle size of 6μ
Treated product F5; Mica powder with an average particle size of 6μ integrated with an epoxy binder of 1%

<Preparation of Composition>
D = 28, twin screw extruder with screw diameter 30 mm, cylinder temperature 320 ° C., screw rotation speed 25
After extruding at 0 rpm, cooling, and cutting with a pelletizer, pellets of the compositions shown in the following Examples and Comparative Examples were obtained. All glass fibers are in cylinder construction 9
It was supplied by a side feeder from the 6th zone in the zone.

<Molding evaluation test> 12
It was dried at 0 ° C. for 5 hours or more, molded by a model connector mold, and evaluated. The model connector A type was arranged with square holes 2 mm, pitch interval 2.5 mm, 24-pole double, wall thickness 1.0 mmt, 0.8 mmφ submarine gate, and protrusion pin clearance average 10 μ. The model connector B type has a wall thickness of 0.6 mmt. The molding machine used was a servo motor driven molding machine with a screw diameter of 28 mm and a mold clamping pressure of 50T.

<Evaluation Test Items and Evaluation Method> (1) Fluidity Model connector type B was used, and the cylinder temperature of the molding machine was 3
Maximum injection speed setting (280 ml / min)
Was molded, and the fluidity was judged by whether or not it could be filled. (Fillable: ○, non-fillable: ×)

(2) Evaluation of burrs Using a model connector type A, a cylinder temperature of 310
Molding was carried out at a temperature of 200 ° C. and an injection speed of 200 ml / min, and protrusion pin mark burrs were measured by a projection type dimension measuring machine. In addition, for a material having a poor mold release, the silicon-based mold release agent was sprayed and then molded, and the burr of the obtained molded product was measured.

(3) Evaluation of releasability Molding was performed by using the model connector A type, and it was determined whether the releasability was possible or continuous molding was possible.

<Examples 1 to 4 and Comparative Examples 1 to 5> PPS resin and silane compound having the compositions shown in Table 1 and 1.0 part by weight of the release agent R-1 and 67 parts by weight of glass fiber K were used. A molding test of fluidity and burrability was conducted on the compounded composition. The results are shown in Table-1.

[0050]

[Table 2]

As described above, the composition of the present invention has excellent fluidity,
Moreover, it is shown that the molding material has less burr. With the compositions shown in Examples 1 to 4, if a product is obtained with a mold accurately manufactured with an assembly accuracy of 5 μ or less, burrs are practically at a level at which there is no problem.

<Examples 5 to 15> 100 parts by weight of the silane compound and glass fiber having the composition shown in Table 2 and 100 parts by weight of the polyphenylene sulfide resin B and the release agent R-1 were added.
Molding tests of fluidity and burrability were conducted with a composition containing 1 part by weight. The results are shown in Table-2.

[0053]

[Table 3]

As described above, proper use of the silane compound makes it possible to maintain fluidity and achieve low flashiness.

<Examples 16 to 23> 10 parts of the releasing agent and the polyphenylene sulfide resin B having the compositions shown in Table 3 were used.
A moldability test of a composition in which 0 parts by weight, 0.8 parts by weight of the silane compound A1, and 67 parts by weight of the glass fiber K are blended,
The releasability and the burr property were evaluated. The results are shown in Table-3.

[0056]

[Table 4]

As described above, it was impossible to release the mold without the release agent, and continuous moldability could not be obtained with the release agent in a small amount.

<Examples 24 to 30> 1 part by weight of PPS resin, glass fiber, other inorganic filler and release agent R1 having the composition shown in Table 4 and 0.8 part by weight of silane compound A1 were blended. Moldability was evaluated using the composition. The results are shown in Table-4.

[0059]

[Table 5]

As described above, when a filler is used in combination with glass fiber, a low burr effect is exhibited.

[0061]

The resin composition of the present invention has excellent fluidity,
In addition, it has low burr and has good releasability even when molding a molded product having a complicated shape, and is useful for precision molded products (IC connectors and the like).

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display area // (C08L 81/02 23:04 23:16)

Claims (3)

[Claims] 1. (A) Orifice diameter 0.0825 ± 0.
0002 inch, orifice length 1.250 ± 0.001
The low-molecular weight component was 50-150g / 10 minutes in melt flow rate measured under conditions of load of 1270g and resin temperature of 600 ± 1 ° F by an orifice of inch, and was suspended and extracted with methylene chloride at room temperature. Is 1
Polyphenylene sulfide resin having a weight% or less; 1
00 parts by weight, (B) polyethylene wax, ethylene-
Propylene copolymer wax, at least one releasing agent selected from the compounds represented by the following formula (1) and the compound represented by the following formula (2); 0.1 to 3 parts by weight [In the formula (1), X represents —CO—R (R represents an alkyl group or an alkenyl group having 6 to 24 carbon atoms)] [In the formula (2), X is the same as above. n is 1 to 3. ] (C) Inorganic filler; Polyphenylene sulfide resin composition consisting of 20 to 300 parts by weight. 2. (A) Orifice diameter 0.0825 ± 0.
0002 inch, orifice length 1.250 ± 0.001
Melt flow rate measured under conditions of load of 1270 g, resin temperature of 600 ± 1 ° F by an inch orifice is 50 to 150 g / 10 minutes, and low molecular weight obtained by suspension extraction with methylene chloride at room temperature. A polyphenylene sulfide resin having a content of 1% by weight or less;
100 parts by weight, (B) polyethylene wax, ethylene-propylene copolymer wax, at least one releasing agent selected from the compound represented by the following formula (1) and the compound represented by the following formula (2); 0 1-3 parts by weight [In the formula (1), X represents —CO—R (R represents an alkyl group or an alkenyl group having 6 to 24 carbon atoms)] [In the formula (2), X is the same as above. n is 1 to 3. ] (C) (a) Glass fiber; 30 to 80 parts by weight (b) At least one inorganic filler selected from glass powder, glass flakes, talc and mica;
A polyphenylene sulfide resin composition comprising 5 to 50 parts by weight. 3. (A) Orifice diameter 0.0825 ± 0.
0002 inch, orifice length 1.250 ± 0.001
The low-molecular weight component was 50-150g / 10 minutes in melt flow rate measured under conditions of load of 1270g and resin temperature of 600 ± 1 ° F by an orifice of inch, and was suspended and extracted with methylene chloride at room temperature. Is 1
Polyphenylene sulfide resin having a weight% or less; 1
At least one release agent selected from the group consisting of (B) polyethylene wax, ethylene-propylene copolymer wax, a compound represented by the following formula (1) and a compound represented by the following formula (2) per 100 parts by weight. 0.1 to 3 parts by weight [In the formula (1), X represents —CO—R (R represents an alkyl group or an alkenyl group having 6 to 24 carbon atoms)] [In the formula (2), X is the same as above. n is 1 to 3. ] (C) Inorganic filler; 20 to 300 parts by weight (D) At least one silane compound selected from the group consisting of epoxyalkoxysilane and aminoalkoxysilane; A method for producing a polyphenylene sulfide resin composition, comprising: