JPH11106656A - Polyarylene sulfide resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyarylene sulfide resin composition that has markedly increased fluidity with extremely reduced burr occurrence and high mechanical strength as toughness at the welded part. SOLUTION: The objective polyarylene sulfide resin composition contains (A) 100 pts.wt. of polyarylene sulfide that has an extraction of <=0.7 wt.% with methylene chloride and the melt viscosity V6 of 20-15,000 poise and bears -SX group (X is an alkali metal or H) of >=15 μmol/g, (B) 0.01-5.0 pts.wt. of isocyanato-alkoxysilane and (C) 0-400 pts.wt. of inorganic filter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyarylene sulfide resin composition and a resin molded product having a weld portion obtained therefrom.

[0002]

2. Description of the Related Art In recent years, thermoplastic resins having high heat resistance and chemical resistance have been demanded as materials for electric / electronic equipment parts, automobile equipment parts, chemical equipment parts and the like. . Polyarylene sulfide (hereinafter sometimes abbreviated as PAS) represented by polyphenylene sulfide (hereinafter sometimes abbreviated as PPS)
Because of its excellent heat resistance, mechanical properties, chemical resistance, moldability, flame retardancy, dimensional stability, and electrical properties, it has recently attracted attention as one of the resins that meets this requirement.

However, the resin has extremely low mechanical strength such as toughness or the like in a portion where two or more flows of the resin flow join and fuse in the mold cavity during molding, that is, a weld portion. Disadvantage. For this reason, there has been a problem that when a thermal stress or a mechanical stress is received, the weld portion is broken. In particular, the above problem was remarkable when pins were driven into the connector. In addition, since the resin has too high a melt fluidity, there is a problem that burrs are easily generated at the time of molding the connector.

In order to improve the mechanical strength such as toughness of a weld portion, several methods have been proposed so far.

Japanese Patent Publication No. 6-39113 discloses a PA.
A resin composition containing a silane compound such as S, epoxyalkoxysilane and an inorganic filler is disclosed. JP-A-9-153383 discloses a connector obtained by injection molding a resin composition containing PAS, epoxyalkoxysilane and an inorganic filler. Tokuhei 6
JP-A-51311 discloses a resin composition containing PAS, aminoalkoxysilane, and an inorganic filler. Also, JP-A-1-193360 and 3-1-1
No. 43452 discloses a resin composition containing PAS, ureidosilane and an inorganic filler. However, the reactivity between the PAS and the silane compound was not sufficient in any case, and improvement in mechanical strength such as toughness of a weld portion and reduction in burrs could not be said to be sufficient. Further, P
Since the fluidity of AS is low, when injection molding is performed to form a molded product such as a connector, a defect due to unfilling is likely to occur. In JP-A-8-253587, in order to increase the reactivity between PAS and an epoxy-based silane coupling agent, the amount (μmol / g) of terminal SX groups (X is an alkali metal or a hydrogen atom) is determined. P specified
A resin composition using AS has been proposed. The PAS resin composition was able to achieve a remarkable improvement in mechanical strength such as impact strength, but when filled through pores of a submarine gate or the like, unfilling may occur, and further improvement in the flowability of PAS is expected. It had been.

JP-A-6-41425 and JP-A-6-41425
In order to reduce burr generation, improve mechanical strength and heat resistance, and further enhance fluidity, JP-A-414426 discloses various types of PPS having isocyanate alkylalkoxysilane in two kinds of PPS having specific properties. A PPS resin composition obtained by kneading the above-mentioned alkoxysilane compound and a fibrous or non-fibrous reinforcing material is disclosed. However, in these, it is essential to mix two types of PPS having specific properties at a predetermined ratio, which leads to an increase in cost.

In the production of PAS, a reaction is carried out in two steps and water is added in two steps, a method using an alkali metal carboxylate, such as sodium acetate or lithium acetate, as a polymerization aid in the reaction system, Alternatively, a method of producing a high molecular weight PAS or the like by crosslinking a low molecular weight PAS by thermal oxidation treatment is used. Therefore, there are also disadvantages such as an increase in the production cost of the PAS or a failure to obtain a sufficient mechanical strength of the PAS.

[0008]

SUMMARY OF THE INVENTION The present invention provides an inexpensive polyarylene sulfide resin composition having extremely high fluidity, extremely low burr formation and high mechanical strength such as weld toughness. Is what you do.

[0009]

Means for Solving the Problems The present inventors have conducted various studies to solve the above problems. As a result, with the given PAS below, unexpectedly combined with an isocyanatoalkylalkoxysilane compound and optionally an inorganic filler, the flowability is significantly improved while the formation of burrs is very low, Further, they have found that an inexpensive polyarylene sulfide resin composition having extremely high mechanical strength such as toughness in a weld portion can be produced, and have completed the present invention.

That is, according to the present invention, (A) the amount of extraction with methylene chloride is 0.7% by weight or less, and the melt viscosity V ₆ is 2%.
100 parts by weight of a polyarylene sulfide having 0 to 15000 poises and having an SX group (X is an alkali metal or a hydrogen atom) of 15 μmol / g or more,
(B) Isocyanatoalkylalkoxysilane compound
0.01 to 5.0 parts by weight, and (C) an inorganic filler 0
It is a polyarylene sulfide resin composition containing 400 parts by weight.

When the resin composition of the present invention is preferably used for a molded product having a weld portion, for example, a connector, there is no occurrence of a molded product defect due to unfilling due to very good fluidity. On the other hand, despite its high fluidity, it has an extremely unique property that burrs are very little generated.
Therefore, the step of removing the generated burrs can be omitted or greatly simplified, which is economically excellent. Furthermore, when the connector is formed, the mechanical strength such as the toughness of the weld portion generated therein is high, so that the connector is not broken from the weld portion when the pin is driven into the connector.

In a preferred embodiment, (2) the (B) isocyanatoalkylalkoxysilane compound is used in an amount of from 0.05 to
(3) The resin composition according to the above (1), which contains 3.0 parts by weight.
(B) The resin composition according to the above (1), which comprises 0.1 to 2.0 parts by weight of the isocyanatoalkylalkoxysilane compound, and (4) the (B) isocyanatoalkylalkoxysilane compound is γ-isocyanatopropyltrisilane. The resin composition according to any one of the above (1) to (3), which is ethoxysilane or γ-isocyanatopropyltrimethoxysilane, (5) the resin composition according to any one of the above (1) to (4) (6) A molded product of a polyarylene sulfide resin having a weld portion obtained by injection molding the resin composition described in (5) above, which is obtained by injection-molding one molded product from two or more gates. ), And (7) the resin molded article according to (5) or (6), wherein the resin molded article is a connector.

The above (A) PAS has many -SX groups. Therefore, it reacts well with many isocyanatoalkylalkoxysilane compounds. Further, the PAS of the present invention has a low extraction amount with methylene chloride. Therefore, there is almost no oligomer having a relatively small molecular weight, and the isocyanatoalkylalkoxysilane compound is not wasted. Further, the isocyanatoalkylalkoxysilane compound has high reactivity. From the above, the PA of the present invention
From S, a PAS resin composition having high reactivity with an isocyanatoalkylalkoxysilane compound and having each of the above properties can be produced by adding a small amount of the agent.

Further, as described below, the PAS of the present invention can be prepared by a method in which the reaction is carried out in two steps and water is added in two steps as in the above-mentioned conventional method, or a PAS using a polymerization aid in the reaction system. Do not use manufacturing methods. Therefore, the obtained P
AS is inexpensive.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The component (A) PAS of the present invention has an extraction amount with methylene chloride of 0.7% by weight or less, preferably 0.6% by weight or less. Within the above range, PA
This is preferable because there are very few oligomers having a relatively low molecular weight in S. When the extraction amount exceeds the above upper limit, the flowability of the resin composition is reduced, and the effect of improving the mechanical strength such as the toughness of a molded product such as a weld portion of a connector is reduced, and the burr is preferably increased. Absent.
Here, the amount of extraction with methylene chloride is a value determined as follows. 4 g of the PAS powder is added to 80 g of methylene chloride, soxhlet extraction is performed for 4 hours, and then cooled to room temperature, and the extracted methylene chloride solution is transferred to a weighing bottle. Further, the container used for the above extraction was placed in a methylene chloride total of 60.
g, and washing is performed in three times, and after collecting the washing solution,
Collect in the weighing bin. Next, heating to about 80 ° C. to evaporate off the methylene chloride in the weighing bin,
It is determined by weighing the residue.

(A) The PAS has a —SX group (X is an alkali metal or a hydrogen atom) of 15 μmol / g or more, preferably 18 to 35 μmol / g, particularly preferably 20 μmol / g.
３０30 mol / g. When the group is less than the above lower limit, P
The reactivity between AS and the isocyanatoalkylalkoxysilane compound is reduced. Here, the quantification of the -SX group was carried out as follows. After previously drying the PAS powder at 120 ° C. for 4 hours, 20 g of the PAS powder is added to 150 g of N-methyl-2-pyrrolidone, and vigorously stirred and mixed at room temperature for 30 minutes so as to eliminate powder agglomerates. Next, after filtering the slurry, washing is repeated seven times using 1 liter of warm water at about 80 ° C. each time. The obtained filter cake is purified water 200
g, and then adjust the pH of the slurry to 4.5 by adding 1N hydrochloric acid. Next, after stirring at 25 ° C. for 30 minutes and filtering, washing is repeated 6 times using 1 liter of hot water at about 80 ° C. each time. The obtained filter cake was slurried again in 200 g of pure water, and then 1N
And quantify with sodium hydroxide.

Further, (A) PAS has a melt viscosity V ₆ of 2
0-15000 poise, preferably 100-10000
Poise, particularly preferably 400 to 5000 poise. If it is less than the above lower limit, the PAS inherent properties such as mechanical strength cannot be obtained, and the reactivity with the isocyanatoalkylalkoxysilane compound is not sufficient, and the object of the present invention is a molded product such as the toughness of a weld portion of a connector. Cannot achieve an increase in the mechanical strength of Exceeding the above upper limit is not preferred because the moldability decreases. Here, the melt viscosity V ₆ was determined to be 300 using a flow tester.
C., a load of 20 kgf / cm ² , L / D = 10/1, measured after holding for 6 minutes.

In the present invention, (A) PAS comprises reacting an alkali metal sulfide with a dihaloaromatic compound in an organic amide solvent, and cooling the gas phase of the reactor during the reaction. The polyarylene sulfide (a) produced by condensing a part of the gas phase therein and refluxing it in the liquid phase can be obtained by washing with an organic solvent and then with water.

Here, the above PAS (a) is disclosed in
-222196.

In this polymerization method, the refluxed liquid has a higher water content than the liquid bulk because of the vapor pressure difference between water and the amide solvent. The reflux liquid having a high water content forms a layer having a high water content at the upper portion of the reaction solution. As a result, residual alkali metal sulfide (eg, Na ₂ S),
Alkali metal halides (eg, NaCl), oligomers, and the like are included in the layer in large amounts. In the conventional method, PAS and N
In a state where the raw materials such as a ₂ S and by-products are uniformly mixed, not only a high molecular weight PAS cannot be obtained, but also
Depolymerization of the produced PAS also occurs, and by-products of thiophenol are observed. However, in the present invention, the above disadvantageous phenomenon can be avoided by actively cooling the gas phase portion of the reaction vessel and returning a large amount of the water-rich reflux liquid to the upper part of the liquid phase so as to inhibit the reaction. It can be considered that such factors can be effectively eliminated and a high molecular weight PAS can be obtained. However, the present invention is not limited only by the effect of the above phenomenon, but by various effects caused by cooling the gas phase part, high molecular weight PAS
Is obtained.

In this polymerization method, it is not necessary to add water during the reaction as in the conventional method. However, this does not preclude the addition of water at all. However, if the operation of adding water is performed, some of the advantages of the present invention are lost. Therefore, preferably, the total water content in the polymerization reaction system is constant throughout the reaction.

The gas phase of the reaction vessel can be cooled either externally or internally, and can be cooled by a cooling means known per se. For example, a method of flowing a cooling medium through an internal coil installed at an upper part in a reaction can, a method of flowing a cooling medium through an external coil or a jacket wrapped around the upper part of the reaction can, and using a reflux condenser installed at the upper part of the reaction can A method such as spraying water or blowing a gas (air, nitrogen, etc.) on the upper portion of the outside of the reaction vessel is conceivable, but any method can be used as long as it has the effect of increasing the amount of reflux in the vessel as a result. May be used. If the outside air temperature is relatively low (for example, normal temperature), appropriate cooling can be performed by removing a heat insulating material conventionally provided on the upper part of the reaction vessel. In the case of external cooling, water condensed on the reactor wall
The amide-based solvent mixture enters the liquid phase along the reaction vessel wall. Thus, the water-rich mixture pools on top of the liquid phase,
Keep the water content there relatively high. For internal cooling,
The mixture condensed on the cooling surface likewise travels down the cooling device surface or the reactor wall and into the liquid phase.

On the other hand, the temperature of the liquid phase bulk is maintained at a predetermined constant temperature or controlled according to a predetermined temperature profile. 230-275 for constant temperature
It is preferred to carry out the reaction at a temperature of ° C for 0.1 to 20 hours. More preferably, the temperature is 240 to 265 ° C for 1 to 6 hours. In order to obtain a higher molecular weight PAS, it is preferable to use two or more reaction temperature profiles. This 2
When performing a step operation, the first step is preferably performed at a temperature of 195 to 240 ° C. If the temperature is low, the reaction rate is too low, which is not practical. If the temperature is higher than 240 ° C., the reaction rate is too high, so that not only a sufficiently high molecular weight PAS cannot be obtained, but also the side reaction rate is significantly increased. The end of the first phase,
The residual ratio of the dihalo aromatic compound in the polymerization reaction system is 1 mol% to 40 mol%.
It is preferable to carry out the reaction at a time point when the molar% is within the range of 3,000 to 20,000. More preferably, the residual ratio of the dihalo aromatic compound in the polymerization reaction system is in the range of 2 mol% to 15 mol%, and the molecular weight is in the range of 5,000 to 15,000. Residual rate is 40 mol%
If it exceeds 2,000, side reactions such as depolymerization are likely to occur in the second stage reaction, while if it is less than 1 mol%, high molecular weight P
It is hard to get AS. Thereafter, the temperature is raised, and the reaction in the final stage is preferably carried out at a reaction temperature of 240 to 270 ° C. for 1 to 10 hours. PAS with sufficiently high molecular weight at low temperature
When the temperature is higher than 270 ° C., side reactions such as depolymerization are liable to occur, making it difficult to stably obtain a high molecular weight product.

As an actual operation, first, under an inert gas atmosphere, dehydration or water addition is performed as necessary so that the amount of water in the alkali metal sulfide in the amide solvent becomes a predetermined amount. The water content is preferably the alkali metal sulfide 1
It is 0.5 to 2.5 mol, especially 0.8 to 1.2 mol, per mol. If it exceeds 2.5 moles, the reaction rate will be low, and the amount of by-products such as phenol will increase in the filtrate after the reaction, and the degree of polymerization will not increase. If the amount is less than 0.5 mol, the reaction rate is too high to obtain a product having a sufficient high molecular weight, and undesirable reactions such as side reactions occur.

In the case of a one-stage reaction at a constant temperature, the cooling of the gas phase during the reaction is preferably carried out from the start of the reaction, but must be carried out at least in the course of raising the temperature to 250 ° C. or lower. In the multi-stage reaction, it is preferable to perform cooling from the first-stage reaction, but it is preferable to perform cooling at the latest after the completion of the first-stage reaction. The degree of the cooling effect is usually the most suitable index of the pressure in the reactor. The absolute value of the pressure varies depending on the characteristics of the reaction vessel, the stirring state, the amount of water in the system, the molar ratio of the dihalo aromatic compound to the alkali metal sulfide, and the like. However, when the pressure in the reaction vessel is reduced as compared with the case where the reaction vessel is not cooled under the same reaction conditions, the amount of the reflux liquid increases, which means that the temperature at the gas-liquid interface of the reaction solution decreases. It is considered that the relative degree of decrease indicates the degree of separation between a layer having a high water content and a layer having no water content. Therefore, it is preferable to perform cooling to such an extent that the internal pressure of the reaction vessel is lower than that in the case where no cooling is performed. The degree of cooling can be appropriately set by those skilled in the art according to the equipment used, operating conditions, and the like.

The organic amide solvent used here is PA
Known for S polymerization, such as N-methylpyrrolidone (NMP), N, N-dimethylformamide,
N, N-dimethylacetamide, N-methylcaprolactam, and the like, and mixtures thereof can be used, with NMP being preferred. They all have a lower vapor pressure than water.

Alkali metal sulfides are also known, for example, lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide, cesium sulfide and mixtures thereof. These hydrates and aqueous solutions may be used. Hydrosulfides and hydrates corresponding to these can be used after being neutralized with the corresponding hydroxides.
Inexpensive sodium sulfide is preferred.

Dihaloaromatic compounds are described in, for example,
It can be selected from those described in JP-A-5-3368, but is preferably p-dichlorobenzene. Further, a copolymer can be obtained by using one or more kinds of para-, meta- or ortho-dihalides of diphenyl ether, diphenyl sulfone or biphenyl in a small amount (20 mol% or less). For example, m-dichlorobenzene, o-dichlorobenzene,
p, p'-dichlorodiphenylether, m, p'-dichlorodiphenylether, m, m'-dichlorodiphenylether, p, p'-dichlorodiphenylsulfone, m, p'-dichlorodiphenylsulfone, m, m '
-Dichlorodiphenyl sulfone, p, p'-dichlorobiphenyl, m, p'-dichlorobiphenyl, m, m'-
Dichlorobiphenyl.

In order to further increase the molecular weight of PAS,
For example, 1,3,5-trichlorobenzene, 1,2,4-
Polyhalo compounds such as trichlorobenzene can also be used, preferably in a concentration of 5 mol% or less, based on the total amount of the para and metadihalo aromatic compounds.

Further, as a small amount of other additives, a terminal stopper and a monohalide as a modifier may be used in combination.

Next, the washing of PAS with an organic solvent is preferably performed by the following method. That is, after filtering the slurry of PAS (a) produced in the above step, the obtained filter cake is dispersed in an organic solvent. The washing is preferable because the oligomer component having a relatively low molecular weight present in the PAS (a) can be satisfactorily removed.

In one embodiment of the washing, first, the PAS (a) slurry produced in the above step is filtered to obtain a PAS cake. Next, the PAS cake is put into an organic solvent, preferably 0.5 to 10 times by weight, and the mixture is stirred and mixed at room temperature to 180 ° C., preferably for 10 minutes to 10 hours, and then filtered. The stirring, mixing and filtration operations are preferably repeated 1 to 10 times. Examples of the organic solvent used for the washing include the organic amide solvents described in the description of the process for producing the PAS (a), xylene, and the like. Preferably, an organic amide solvent is used. The organic amide solvent may be the same as or different from the one used in the production process of PAS (a). As the organic amide solvent, N-methylpyrrolidone is particularly preferably used.

The subsequent washing with water can be performed according to a known method. However, it is preferably carried out by dispersing the filter cake obtained after washing with the above organic solvent in water. For example, the above-mentioned filter cake is poured into water, preferably 1 to 5 times in weight, and is preferably mixed at room temperature to 90 ° C., preferably for 5 minutes to 10 hours, and then filtered. The stirring, mixing and filtering operations are preferably performed for 2 hours.
By repeating 〜１０10 times, the solvent and by-product salts attached to the PAS are removed, and the water washing is completed. By performing water washing as described above, efficient washing can be performed with a smaller amount of water than in a washing method in which water is poured into a filter cake. Further, the present inventor has found that, according to the conventional solvent removal by drying, the reactivity between PAS and the isocyanatoalkylalkoxysilane compound is reduced. However, if the solvent is removed by washing with water as in the present invention, high reactivity between PAS and the isocyanatoalkylalkoxysilane compound can be maintained.

In the present invention, the PAS obtained as described above may be further subjected to an acid treatment. The acid treatment is carried out at a temperature of 100 ° C or lower, preferably at a temperature of 40 to 80 ° C. If the temperature exceeds the above upper limit, the PAS molecular weight after the acid treatment decreases, which is not preferable. On the other hand, when the temperature is lower than 40 ° C., the remaining inorganic salt precipitates out and lowers the fluidity of the slurry, which hinders the continuous treatment process, which is not preferable. The concentration of the acid solution used for the acid treatment is preferably 0.01 to 5.0% by weight. Further, the pH of the acid solution after the acid treatment is preferably 4.0 to 5.0. By adopting the above concentration and pH, most of -SY (Y represents an alkali metal) terminal in PAS to be treated can be converted to -SH terminal, and corrosion of plant equipment and the like can be achieved. This is preferable because it can prevent The time required for the acid treatment depends on the temperature of the acid treatment and the concentration of the acid solution.
Minutes or more, particularly preferably 10 minutes or more. If it is less than the above, -SY terminal in PAS cannot be sufficiently converted to -SH terminal, which is not preferable. In the acid treatment, for example, acetic acid,
Formic acid, oxalic acid, phthalic acid, hydrochloric acid, phosphoric acid, sulfuric acid, sulfurous acid, nitric acid, boric acid, carbonic acid and the like are used, and acetic acid is particularly preferred. By performing the treatment, an alkali metal such as sodium which is an impurity in the PAS can be reduced. Therefore, elution of alkali metal such as sodium during use of the product and deterioration of electrical insulation can be suppressed.

The component (B) isocyanatoalkylalkoxysilane compound used in the present invention is preferably γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropyltrimethoxysilane, γ-isocyanatopropylmethyldimethoxysilane, γ-isocyanatopropylmethyldiethoxysilane and the like. The amount of the component (B) isocyanatoalkylalkoxysilane compound is based on 100 parts by weight of the component (A) PAS.
The lower limit is 0.01 part by weight, preferably 0.05 part by weight, particularly preferably 0.1 part by weight, and the upper limit is 5.0 parts by weight.
Parts by weight, preferably 3.0 parts by weight, particularly preferably 2.
0 parts by weight. When the component (B) is less than the above lower limit, the fluidity of the resin composition cannot be increased, and the mechanical strength such as the toughness of a molded product, for example, a weld portion of a connector, becomes low, and the burr becomes long. Exceeding the above-mentioned upper limits causes a reduction in molding workability due to thickening, a reduction in mechanical strength, a poor appearance of a molded product, and an increase in cost.

In the present invention, (C) an inorganic filler can be further added as an optional component. (C) The inorganic filler is not particularly limited, and for example, a powdery / flaky filler, a fibrous filler, and the like can be used. Examples of the powdery / flaky filler include alumina, talc, mica, kaolin, clay, titanium oxide, calcium carbonate,
Calcium silicate, calcium phosphate, calcium sulfate, magnesium oxide, magnesium phosphate, silicon nitride, glass, hydrotalcite, zirconium oxide,
Glass beads, carbon black and the like can be mentioned. Examples of the fibrous filler include glass fiber, asbestos fiber, carbon fiber, silica fiber, silica / alumina fiber, potassium titanate fiber, and polyaramid fiber. In addition, a filler such as a ZnO tetrapot, a metal salt (eg, zinc chloride, lead sulfate, etc.), an oxide (eg, iron oxide, molybdenum dioxide, etc.), and a metal (eg, aluminum, stainless steel, etc.) may be used. it can. These can be used alone or in combination of two or more.

The upper limit of the amount of the component (C) inorganic filler is 400 parts by weight, preferably 200 parts by weight, particularly preferably 100 parts by weight, based on 100 parts by weight of the PAS of the component (A). If the component (C) exceeds the above upper limit, the moldability deteriorates, which is not preferable. In order to increase the mechanical strength, it is preferable to add 0.01 parts by weight or more.

Further, if necessary, in addition to the above components,
Known additives and fillers such as antioxidants, ultraviolet absorbers, release agents, heat stabilizers, lubricants, colorants, and the like can be added.

The method for mixing the above components is not particularly limited. A method generally used widely, for example, a method of mixing the components with a mixer such as a Henschel mixer can be used.

In order to produce a molded article from the resin composition of the present invention, for example, the above-mentioned mixture is melt-kneaded with a single-screw or twin-screw extruder to form a pellet-like composition, which is then injection-molded. Can be implemented easily and economically. However, the present invention is not limited to this, and a method of mixing and molding a part of the necessary components by master batch or side feed may be used.

In the present invention, the weld portion is a portion formed by an injection molding method and in which two or more flow interfaces of a resin flow merge and fuse in a mold cavity. The weld portion is likely to occur when there is a void in the molded product, or when there is a change in the wall thickness and the material cannot flow unidirectionally from the thick wall to the thin wall. In the case where there are two or more gates, or the formation of a ring, a circle, or a rectangular cylinder even with a one-point gate, the occurrence of welds cannot be avoided.
In general, the weld portion can be identified from the appearance of linear color unevenness on the surface of the molded product or the appearance of a pattern in which the resin flows merge.

The molded article of the present invention is preferably obtained by injection-molding with two or more gates provided in one mold cavity corresponding to one molded article during injection molding. . In the molded article, an interface (weld portion) for joining two or more resin flows corresponding to the number of gates is always formed, and the interface region is wide. Therefore, conventionally, the strength defect of the weld portion is remarkable. Fatal hindrance to practical strength occurred. The present invention is particularly effective in improving a significant weld defect which occurs in a molded product using two or more gates. Further, the resin composition of the present invention,
Since the fluidity is remarkably high, a molded article having such a weld portion does not cause a defect due to unfilling.

Examples of the molded product having the above-mentioned welded parts include a connector, a coil bobbin, a printed circuit board, a chassis for an electronic component, a lamp socket as an electric heating component, a dryer grill, a thermostat base, and a thermostat case. Brush holders, bearings, motor cases, etc. as motor parts, nails for copiers as precision equipment, aperture parts for cameras, etc.
Watch case, watch base plate, etc., exhaust gas circulation valve, carburetor, alternator terminal block, tachometer housing, battery housing, etc. as automobile parts, or cleansing frame, insulator, pipe bracket, pump casing, tower casing, etc. as chemical equipment parts Many functional components. Particularly preferably, it is used as a connector. Although these molded articles do not always have a welded portion, it is difficult to avoid the welded portion due to its function. Also,
The above-mentioned molded article is an example, and the molded article having a weld portion is not limited thereto.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[0045]

In the examples, melt viscosity V ₆ is a value measured using a Shimadzu Flow Tester CFT-500C.

Synthesis Example 1 In a 150-liter autoclave, 19.285 kg of flaky sodium sulfide (60.7% by weight Na ₂ S) and N
45.0 kg of -methyl-2-pyrrolidone (hereinafter abbreviated as NMP) was charged. The temperature was raised to 204 ° C. while stirring under a nitrogen stream to distill 4.757 kg of water. Thereafter, the autoclave was sealed and cooled to 180 ° C., and 22.500 kg of paradichlorobenzene (hereinafter may be abbreviated as p-DCB) and 18.0 kNMP were used.
g. 1 kg using nitrogen gas at a liquid temperature of 150 ° C
/ Cm ² G and the temperature was raised. Liquid temperature 220 ° C
While stirring for 5 hours, water was sprinkled with a sprinkler attached to the outside of the upper part of the autoclave to cool the upper part of the autoclave. Thereafter, the temperature was raised while sprinkling water, and the liquid temperature was raised to 26.
The temperature was adjusted to 0 ° C., and then the mixture was stirred at that temperature for 3 hours to proceed with the reaction.
Next, the temperature was lowered and the cooling at the top of the autoclave was stopped. During the cooling of the upper part of the autoclave, the liquid temperature was kept constant so as not to drop.

After filtering the obtained polymerization slurry, the obtained filter cake was slurried in unused NMP (slurry concentration: 15% by weight). Then at 120 ° C. for 30
The mixture was stirred for minutes, filtered to remove NMP, and then the filter cake was poured into warm water of about 80 ° C. (about twice the weight of the filter cake by weight), sufficiently stirred for about 30 minutes, and then filtered. This operation of water washing and filtration was repeated seven times. Thereafter, the obtained filter cake was dried in a hot air circulating drier at 120 ° C. for about 5 hours to obtain a white powdery PPS. PPS obtained
(P-1) V ₆ of was 630 poise.

Synthesis Example 2 After filtering the polymerization slurry obtained in the same manner as in Synthesis Example 1, the obtained filter cake was slurried in unused NMP (slurry concentration: 15% by weight). Then 120 ° C
At 30 ° C., filter to remove NMP, then filter cake at about 80 ° C. hot water (about twice the weight of filter cake by weight)
The mixture was put into the flask, stirred sufficiently for about 30 minutes, and then filtered. This operation of water washing and filtration was repeated twice. After the obtained filter cake was slurried in pure water, the slurry was adjusted to pH 5.0 by adding acetic acid and stirred at 50 ° C. for 30 minutes to perform an acid treatment. The procedure of filtration after acid treatment, addition of pure water, stirring and filtration was repeated four times. Next, the obtained filter cake was dried in a hot air circulating drier at 120 ° C. for about 5 hours to obtain PPS as a white powder. The obtained PP
V ₆ of S (P-2) was 580 poise.

Synthesis Example 3 (Used in Comparative Example) The same operation as in Synthesis Example 1 was carried out except that washing with unused NMP was not performed. V of the obtained PPS (P-3)
₆ had 520 poise.

Synthesis Example 4 (Used in Comparative Example) After filtering the polymerization slurry obtained in the same manner as in Synthesis Example 1, NMP was distilled out of the cake in an oil bath at 200 ° C. under a reduced pressure of 10 torr using an evaporator. Until it runs out
Dry for about 1 hour. Thereafter, the mixture was cooled, poured into warm water of about 80 ° C. (about twice the weight of the filter cake), sufficiently stirred for about 30 minutes, and then filtered. This operation of water washing and filtration was repeated seven times. Thereafter, the filter cake was dried in a hot air circulating drier at 120 ° C. for 5 hours to obtain a brown powdery product. V ₆ of the obtained PPS (P-4) was 780 poise.

Synthesis Example 5 (Used in Comparative Example) During the polymerization reaction, sodium acetate trihydrate was used as a polymerization aid.
The procedure was carried out under the same conditions as in Synthesis Example 1 except that 0 kg was added, 22.850 kg of p-DCB was charged, and the upper part of the autoclave was not cooled. The obtained PP
V ₆ of S (P-5) was 890 poise.

[0052]

EXAMPLES 1 TO 7 AND COMPARATIVE EXAMPLES 1 TO 11 Using the amounts (parts by weight) of each PPS, each silane compound and each filler shown in Tables 1 and 2, the mixture was preliminarily mixed with a Henschel mixer for 5 minutes and uniformly mixed. Then, using a 40 mmφ biaxial kneader, the mixture was melt-kneaded at a barrel setting temperature of 320 ° C. and a rotation speed of 200 rpm, and extruded to form pellets. When glass fiber (CS 3E-961S, trademark, manufactured by Nitto Boseki Co., Ltd.) is used as the filler, the glass fiber is introduced from the side of the twin-screw kneader by an auto feeder so as to have a predetermined compounding ratio. Kneaded. The calcium carbonate used as the filler was Whiten-SB (trademark) manufactured by Shiraishi Calcium Co., Ltd.

Further, the resulting pellets were molded by an injection molding machine set at a cylinder temperature of 320 ° C. and a mold temperature of 130 ° C., and the following flat plates and connectors were prepared and subjected to various characteristics tests. -Weld strength was determined by preparing a flat plate having a width of 80 mm, a length of 180 mm, and a thickness of 3 mm using a mold having a film gate on both sides, and then forming a plate-like shape (1/8)
', No notch) and then cut to ASTM D256
The Izod impact strength was measured and evaluated according to.・ Burr characteristics are 130mm long x 9mm wide x 14m deep
A long connector consisting of 200-m and 200-pin was prepared, and the length of a burr generated in a slit (gap of 20 μm) formed for degassing was measured and evaluated. The fluidity of each resin composition is 315.6 ° C., 5
MF under kg load condition in accordance with ASTM D1238
R was measured and evaluated.

The isocyanatoalkylalkoxysilane compound (B) can be obtained from γ-isocyanatopropyltriethoxysilane (A-1310, trademark, manufactured by Nippon Unicar Co., Ltd.) and γ-isocyanatopropyltrimethoxysilane (Y5187, trademark, Japan (Manufactured by Unicar Co., Ltd.). As comparative substances, γ-glycidoxypropyltrimethoxysilane (A-187, trademark, manufactured by Nippon Unicar Co., Ltd.), γ-aminopropyltriethoxysilane (A-1100, trademark, manufactured by Nippon Unicar Co., Ltd.) and γ-ureidopropyltriethoxysilane (A-11
60, trademark, manufactured by Nippon Unicar Co., Ltd.).

The above results are shown in Tables 1 and 2.

[0056]

[Table 1]

[0057]

[Table 2] In Tables 1 and 2, IPTES indicates γ-isocyanatopropyltriethoxysilane, IPTMS indicates γ-isocyanatopropyltrimethoxysilane, GPTMS indicates γ-glycidoxypropyltrimethoxysilane,
APTES indicates γ-aminopropyltriethoxysilane and UPTES indicates γ-ureidopropyltriethoxysilane.

Examples 1, 3 and 4 show the PPS of the present invention.
(P-1) The amount of IPTES blended in (P-1) was changed within the range of the present invention. As the amount of IPTES increases,
The Izod impact strength increases and the burr length decreases.
Although the MFR tended to decrease somewhat, the effects of the present invention could be sufficiently achieved. Example 2 contains IPTMS. Almost the same results as those obtained by blending IPTES were obtained. In Examples 5 and 6, the amount of the inorganic filler was increased and the amount was not mixed at all. It has been found that good fluidity can be maintained even when the amount of the inorganic filler is increased. Example 7 uses a different PPS (P-2) within the scope of the present invention. The same result as in the case of P-1 was obtained.

On the other hand, Comparative Example 1 does not contain the component (B) the isocyanatoalkylalkoxysilane compound. Compared to Example 1, the MFR was significantly reduced, the Izod impact strength was significantly reduced, and the burr length was significantly longer. Comparative Example 2 (corresponding to the resin composition described in JP-B-6-39113 or JP-A-9-153383) and Comparative Example 3 (corresponding to the resin composition described in JP-B-6-51311). ) And Comparative Example 4 (Japanese Unexamined Patent Publication No.
It corresponds to the resin composition described in JP-A-193360 or JP-A-3-43452. ) Are GPTMS, APTES and UPTES, respectively, in place of the isocyanatoalkylalkoxysilane compound (B) of the present invention.
Is used. In any case, compared to Example 1, M
FR significantly decreased, Izod impact strength decreased, and burr length increased. In Comparative Example 5, the amount of the IPTES compounded was beyond the range of the present invention. The melt viscosity of the resin composition was remarkably increased, and the resin composition was clogged in the kneader, and kneading was impossible. In Comparative Example 6, the blending amount of the glass fiber exceeded the range of the present invention. As in the above, clogging occurred in the kneading machine, and kneading was impossible. Comparative Example 7
Nos. And 8 do not contain any isocyanatoalkylalkoxysilane compound. In Comparative Example 7 as compared with Example 5, and in Comparative Example 8 as compared with Example 6, a remarkable increase in burr length was observed. Comparative Examples 9-1
1 is a PPS other than the PPS of the present invention (P-3, P-3, respectively)
-4 and P-5). Compared with Example 1, the MFR was significantly reduced, the Izod impact strength was significantly reduced, and the burr length was also significantly increased.

[0060]

According to the present invention, there is provided a polyarylene sulfide resin composition having extremely high fluidity, extremely low burr formation, and high mechanical strength such as toughness of a weld portion.

Claims (6)

[Claims] (1) The amount of (A) extracted with methylene chloride is 0.7
Or less by weight%, melt viscosity V ₆ is 20 to 15,000 poise, and -SX group (X is an alkali metal or a hydrogen atom) is polyarylene sulfide 100 parts by weight is 15 micromol / g or more, (B) A polyarylene sulfide resin composition comprising 0.01 to 5.0 parts by weight of an isocyanatoalkylalkoxysilane compound and 0 to 400 parts by weight of an inorganic filler (C). 2. The resin composition according to claim 1, comprising (B) 0.05 to 3.0 parts by weight of an isocyanatoalkylalkoxysilane compound. 3. The resin composition according to claim 1, comprising (B) 0.1 to 2.0 parts by weight of an isocyanatoalkylalkoxysilane compound. 4. A molded product of a polyarylene sulfide resin having a weld portion, obtained by injection-molding the resin composition according to claim 1. 5. The resin molded product according to claim 5, which is obtained by injection molding one molded product from two or more gates. 6. The resin molded product is a connector.
Or the resin molded product according to 5.