JP2021031613A - Polyphenylene sulfide resin composition and molded article - Google Patents

Abstract

To provide a PPS resin composition that is extremely excellent in weld strength and cold thermal shock resistance while maintaining high mechanical strength and dimensional accuracy, and to provide a molded article that is obtained by injection molding.SOLUTION: Provided is a polyphenylene sulfide resin composition obtained by incorporating, to (A) polyphenylene sulfide resin 100 pts.wt., (B) glass fiber by 60 to 100 pts.wt., and (C) calcium carbonate by 80 to 120 pts.wt., and in which (B) glass fiber is obtained by incorporating (B-1) glass fiber by 30 to 50 pts.wt. and (B-2) milled glass fiber by 30 to 50 pts.wt., and the number average fiber length of the glass fiber is 100 to 200 μm.SELECTED DRAWING: None

Description

The present invention provides a PPS resin composition having extremely excellent weld strength and cold-heat impact resistance while maintaining high mechanical strength and dimensional accuracy, and an injection-molded molded product.

Polyphenylene sulfide resin (hereinafter abbreviated as PPS resin) has a good balance of rigidity, heat resistance, heat resistance, water resistance, chemical resistance and molding processability, and is therefore widely used in electrical / electronic parts, water-related parts and automobile parts. It is used.

In addition to mechanical strength, dimensional accuracy is required for these applications. So far, PPS resin has been reinforced with glass fiber, and if necessary, non-fibrous inorganic filler such as calcium carbonate has been added. PPS resin compositions and the like have been proposed.

For example, Patent Document 1 discloses a PPS resin composition in which a PPS resin is reinforced with glass fibers and has an excellent balance of strength, size, and fluidity. Further, Patent Documents 2, 4, 5, 7, and 8 disclose a PPS resin composition containing glass fibers crushed by a ball mill, a cutter mill, or the like, or glass fiber powder. Further, Patent Documents 6 and 9 disclose PPS resin compositions containing mineral fibers and a powder-granular filler such as calcium carbonate. Further, Patent Document 3 contains a PPS resin composition in which a granular filler harder than glass fiber is blended to forcibly break the glass fiber during melt-kneading, and Patent Document 10 crushes and melts a molded product. A PPS resin composition obtained by kneading and forcibly breaking glass fibers is disclosed.

Japanese Unexamined Patent Publication No. 2019-52323 Japanese Unexamined Patent Publication No. 2018-168330 Japanese Unexamined Patent Publication No. 2013-155310 Japanese Unexamined Patent Publication No. 2013-216003 Japanese Unexamined Patent Publication No. 2015-74674 Japanese Unexamined Patent Publication No. 5-70688 Japanese Unexamined Patent Publication No. 8-217975 Japanese Unexamined Patent Publication No. 10-21902 Japanese Unexamined Patent Publication No. 11-116804 Japanese Unexamined Patent Publication No. 2001-81336

In recent years, as the number of parts mounted on automobiles has increased, there is a growing need for space saving in the engine room. Therefore, the product has been downsized, and the development has shifted to a module that integrates multiple functions by combining multiple components instead of one component. Along with this, a thinner wall and a more complicated shape are required, so that high mechanical strength is required.

In particular, in an automobile charging starter, a PPS resin having excellent heat resistance and dimensional accuracy is used because a plurality of parts are combined and mounted in an engine room.

In addition, as the performance of products has improved, the resin parts used have become smaller, more complex, and thinner, so high weld strength and excellent fluidity are also important issues.

Furthermore, insert metals such as collars and busbars are included, and a large number of resin welds are formed in the resin parts due to the increase in the number of gates. It may cause cracks in the resin weld due to the difference in the coefficient of linear expansion of the metal.

Therefore, there is a demand for a PPS resin having heat resistance and dimensional accuracy in addition to mechanical strength, and also having high weld strength, fluidity, and cold thermal impact resistance.

However, in Patent Document 1, although there is a description of tensile strength, there is no description regarding dimensional accuracy and thermal impact resistance, and the dimensional accuracy in the present invention is not satisfied. In Patent Documents 2, 4, 5, 7, and 8, although there is a description of tensile strength, weld strength, etc., there is no description of dimensional accuracy and thermal impact resistance, and the dimensional accuracy in the present invention is not satisfied. .. Further, although Patent Documents 6 and 9 describe the tensile strength, no specific study on dimensional accuracy and thermal impact resistance has been carried out. Further, in Patent Documents 3 and 10, although there is a description about the glass fiber length, specific studies on tensile strength, dimensional accuracy, and thermal impact resistance have not been carried out.

The present invention provides a PPS resin composition having extremely excellent weld strength and cold-heat impact resistance while maintaining high mechanical strength and dimensional accuracy, and an injection-molded molded product.

The present inventors have reached the present invention as a result of repeated diligent studies in order to solve the above problems. That is, the present invention provides the following.
(1) A polyphenylene sulfide resin composition comprising 100 parts by weight of (A) polyphenylene sulfide resin, (B) 60 to 100 parts by weight of glass fiber, and (C) 80 to 120 parts by weight of calcium carbonate. As for (B) glass fiber, 30 to 50 parts by weight of (B-1) glass fiber and 30 to 50 parts by weight of milled glass fiber are blended, and (B) the number average of glass fibers is averaged. A polyphenylene sulfide resin composition having a fiber length of 100 to 200 μm.
(2) The polyphenylene sulfide resin composition according to (1), wherein the fiber diameter of the glass fiber (B) is 9.0 to 14.0 μm.
(3) The polyphenylene sulfide resin composition according to (1) or (2), wherein the weight ratio of the blending amount of the (B) glass fiber and (C) calcium carbonate is 1: 1 to 1: 1.25.
(4) A molded product comprising the polyphenylene sulfide resin composition according to any one of (1) to (3).
(5) The molded product according to (4), wherein the molded product is a molded product containing a metal insert.

In the present invention, a PPS resin composition in which PPS resin, glass fiber, milled glass fiber and calcium carbonate are blended and the number average fiber length of the glass fiber is 100 to 200 μm provides high mechanical strength and dimensional accuracy. It has been found that it has both high weld strength and excellent fluidity, and is suitable for a compact, complicated, and thin-walled insert metal-encapsulated molded product. The PPS resin composition of the present invention is useful for automobile parts in general, and is particularly useful for small, complicated, and thin-walled insert metal-encapsulated molded products in which a plurality of parts are combined.

It is the schematic front view (a) and schematic side view (b) of the molded article for dimensional accuracy evaluation. It is the schematic of the metal insert molded article used for the evaluation of the cold thermal shock resistance. (A) is a view seen from above, and (b) is a view seen from the side.

Hereinafter, embodiments of the present invention will be described. In the present invention, "weight" means "mass".

Since the resin composition of the present invention is required to have heat resistance, it is a composition containing a polyphenylene sulfide resin (hereinafter referred to as PPS resin).

The (A) PPS resin used in the present invention is a polymer having a repeating unit represented by the following structural formula, and is a polymer.

From the viewpoint of heat resistance, a polymer containing 70 mol% or more, more preferably 90 mol% or more of the polymer containing the repeating unit represented by the above structural formula is preferable. Further, less than 30 mol% of the repeating unit of the PPS resin may be composed of a repeating unit having the following structure or the like.

The contents of the polyhalogenated aromatic compound, the sulfidizing agent, the polymerization solvent, the molecular weight modifier, the polymerization aid and the polymerization stabilizer used in the production method of the present invention will be described below.

[Polyhalogenated aromatic compounds]
The polyhalogenated aromatic compound is a compound having two or more halogen atoms in one molecule. Specific examples include p-dichlorobenzene, m-dichlorobenzene, o-dichlorobenzene, 1,3,5-trichlorobenzene, 1,2,4-trichlorobenzene, 1,2,4,5-tetrachlorobenzene, and hexa. Polyhalogenated aromatics such as chlorobenzene, 2,5-dichlorotoluene, 2,5-dichloro-p-xylene, 1,4-dibromobenzene, 1,4-diiodobenzene, 1-methoxy-2,5-dichlorobenzene. Group compounds are mentioned, and p-dichlorobenzene is preferably used. It is also possible to combine two or more different polyhalogenated aromatic compounds to form a copolymer, but it is preferable that the p-dihalogenated aromatic compound is the main component.

The amount of the polyhalogenated aromatic compound used is 0.9 to 2.0 mol, preferably 0.95 to 1.5 mol, per 1 mol of the sulfidizing agent, from the viewpoint of obtaining a PPS resin having a viscosity suitable for processing. More preferably, the range of 1.005 to 1.2 mol can be exemplified.

[Sulfidating agent]
Examples of the sulfidizing agent include alkali metal sulfides, alkali metal hydrosulfides, and hydrogen sulfides.

Specific examples of the alkali metal sulfide include lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide, cesium sulfide, and a mixture of two or more of these, and sodium sulfide is preferably used. These alkali metal sulfides can be used as hydrates or aqueous mixtures, or in the form of anhydrides.

Specific examples of the alkali metal hydrosulfide include sodium hydrosulfide, potassium hydrosulfide, lithium hydrosulfide, rubidium hydrosulfide, cesium hydrosulfide, and a mixture of two or more of these, and among them, sodium hydrosulfide. Is preferably used. These alkali metal hydrosulfides can be used as hydrates or aqueous mixtures, or in the form of anhydrides.

Further, a sulfidizing agent prepared in situ in the reaction system from alkali metal hydrosulfide and alkali metal hydroxide can also be used. Further, a sulfidizing agent can be prepared from alkali metal hydrosulfide and alkali metal hydroxide, and this can be transferred to a polymerization tank for use.

Alternatively, a sulfidizing agent prepared in situ in the reaction system from alkali metal hydroxides such as lithium hydroxide and sodium hydroxide and hydrogen sulfide can also be used. Further, a sulfidizing agent can be prepared from alkali metal hydroxides such as lithium hydroxide and sodium hydroxide and hydrogen sulfide, and the sulfidizing agent can be transferred to a polymerization tank for use.

The amount of the charged sulfidating agent shall mean the residual amount obtained by subtracting the lost amount from the actual charged amount when a partial loss of the sulfidizing agent occurs before the start of the polymerization reaction due to a dehydration operation or the like.

It is also possible to use an alkali metal hydroxide and / or an alkaline earth metal hydroxide in combination with the sulfide agent. Specific examples of the alkali metal hydroxide include sodium hydroxide, potassium hydroxide, lithium hydroxide, rubidium hydroxide, cesium hydroxide, and a mixture of two or more of these as preferable, and alkaline soil. Specific examples of the metal hydroxide include calcium hydroxide, magnesium hydroxide, strontium hydroxide, barium hydroxide and the like, and sodium hydroxide is preferably used.

When alkali metal hydrosulfide is used as the sulfidizing agent, it is particularly preferable to use alkali metal hydroxide at the same time, but the amount used is 0.95 to 1. per 1 mol of alkali metal hydrosulfide. The range of 20 mol, preferably 1.00 to 1.15 mol, more preferably 1.005 to 1.100 mol can be exemplified.

[Polymerization solvent]
It is preferable to use an organic polar solvent as the polymerization solvent. Specific examples include N-alkylpyrrolidones such as N-methyl-2-pyrrolidone and N-ethyl-2-pyrrolidone, caprolactams such as N-methyl-ε-caprolactam, and 1,3-dimethyl-2-imidazolidi. Examples thereof include aprotic organic solvents typified by non-, N, N-dimethylacetamide, N, N-dimethylformamide, hexamethylphosphate triamide, dimethylsulfone, tetramethylenesulfocide, and mixtures thereof, all of which are used. It is preferably used because of its high reaction stability. Among these, N-methyl-2-pyrrolidone (hereinafter, may be abbreviated as NMP) is particularly preferably used.

The amount of the organic polar solvent used is selected in the range of 2.0 to 10 mol, preferably 2.25 to 6.0 mol, more preferably 2.5 to 5.5 mol, per 1 mol of the sulfidizing agent. ..

[Molecular weight regulator]
A monohalogenated compound (not necessarily an aromatic compound) is used in combination with the above-mentioned polyhalogenated aromatic compound in order to form the terminal of the PPS resin to be produced, or to adjust the polymerization reaction or molecular weight. be able to.

[Polymerization aid]
It is also one of the preferable embodiments to use a polymerization aid in order to obtain a PPS resin having a relatively high degree of polymerization in a shorter time. Here, the polymerization aid means a substance having an action of increasing the viscosity of the obtained PPS resin. Specific examples of such polymerization aids include, for example, organic carboxylic acid metal salts, water, alkali metal chlorides, organic sulfonates, alkali metal sulfates, alkaline earth metal oxides, alkali metal phosphates and Alkaline earth metal phosphate and the like can be mentioned. These may be used alone or in combination of two or more. Of these, organic carboxylic acid metal salts and / or water are preferably used.

The organic carboxylic acid metal salt is a general formula R (COMM) _n (in the formula, R is an alkyl group, a cycloalkyl group, an aryl group, an alkylaryl group or an arylalkyl group having 1 to 20 carbon atoms. M is an alkali metal selected from lithium, sodium, potassium, rubidium and cesium. N is an integer of 1 to 3). The organic carboxylic acid metal salt can also be used as a hydrate, an anhydride or an aqueous solution. Specific examples of the organic carboxylate metal salt include lithium acetate, sodium acetate, potassium acetate, sodium propionate, lithium valerate, sodium benzoate, sodium phenylacetate, potassium p-toluic acid, and mixtures thereof. Can be mentioned.

The organic carboxylic acid metal salt is a reaction in which an organic acid and one or more compounds selected from the group consisting of alkali metal hydroxides, alkali metal carbonates and alkali metal bicarbonates are added in approximately equal chemical equivalents and reacted. May be formed by. Among the above organic carboxylic acid metal salts, the lithium salt has high solubility in the reaction system and has a large auxiliary effect, but is expensive, and the potassium, rubidium and cesium salts have insufficient solubility in the reaction system. Therefore, sodium acetate, which is inexpensive and has an appropriate solubility in a polymerization system, is most preferably used.

When these polymerization aids are used, the amount used is usually in the range of 0.01 mol to 0.7 mol with respect to 1 mol of the charged alkali metal sulfide, and is 0.1 to 1 in the sense of obtaining a higher degree of polymerization. The range of 0.6 mol is preferable, and the range of 0.2 to 0.5 mol is more preferable.

Further, using water as a polymerization aid is one of the effective means for obtaining a resin composition having a highly balanced fluidity and high toughness. In that case, the amount to be added is usually in the range of 0.5 mol to 15 mol, preferably in the range of 0.6 to 10 mol in order to obtain a higher degree of polymerization, with respect to 1 mol of the charged alkali metal sulfide. The range of 1-5 mol is more preferred.

The timing of addition of these polymerization aids is not particularly specified, and may be added at any time of the pre-process, the start of polymerization, and the middle of polymerization, which will be described later, or may be added in a plurality of times. When an organic carboxylic acid metal salt is used as the polymerization aid, it is more preferable to add it at the same time as the start of the previous step or the start of polymerization because it is easy to add. When water is used as a polymerization aid, it is effective to add the polyhalogenated aromatic compound in the middle of the polymerization reaction after charging it.

[Polymerization stabilizer]
A polymerization stabilizer can also be used to stabilize the polymerization reaction system and prevent side reactions. The polymerization stabilizer contributes to the stabilization of the polymerization reaction system and suppresses undesired side reactions. One guideline for the side reaction is the production of thiophenol, and the production of thiophenol can be suppressed by adding a polymerization stabilizer. Specific examples of the polymerization stabilizer include compounds such as alkali metal hydroxides, alkali metal carbonates, alkaline earth metal hydroxides, and alkaline earth metal carbonates. Among them, alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, and lithium hydroxide are preferable. Since the above-mentioned organic carboxylic acid metal salt also acts as a polymerization stabilizer, it is one of the polymerization stabilizers used in the present invention. Further, when an alkali metal hydrosulfide is used as the sulfide agent, it is particularly preferable to use the alkali metal hydroxide at the same time, but here, the alkali metal water which is excessive with respect to the sulfide agent. Oxides can also be polymerization stabilizers.

These polymerization stabilizers can be used alone or in combination of two or more. The ratio of the polymerization stabilizer to 1 mol of the charged alkali metal sulfide is usually 0.02 to 0.2 mol, preferably 0.03 to 0.1 mol, and more preferably 0.04 to 0.09 mol. It is preferable to use in. If this ratio is small, the stabilizing effect is insufficient, and if it is too large, it is economically disadvantageous and the polymer yield tends to decrease.

The timing of addition of the polymerization stabilizer is not particularly specified, and it may be added at any time of the pre-process, the start of polymerization, and the middle of polymerization, which will be described later, or it may be added in a plurality of times. It is more preferable because it is easy to add at the same time at the start of the process or the start of polymerization.

Next, the pre-step, the polymerization reaction step, and the recovery step will be specifically described step by step.

[pre-process]
The sulfidating agent is usually used in the form of a hydrate, but before adding the polyhalogenated aromatic compound, the mixture containing the organic protic solvent and the sulfidizing agent is heated to remove an excess amount of water. It is preferable to remove it. If too much water is removed by this operation, it is preferable to add the insufficient water to replenish the water.

Further, as described above, as the sulfidizing agent, an alkali metal sulfide prepared from alkali metal hydrosulfide and alkali metal hydroxide in situ in the reaction system or in a tank separate from the polymerization tank is also used. be able to. Although this method is not particularly limited, it is desirable to use alkali metal hydrosulfide and alkali metal hydroxide as an organic polar solvent in a temperature range of room temperature to 150 ° C., preferably room temperature to 100 ° C. in an inert gas atmosphere. In addition, a method of distilling off water by raising the temperature to at least 150 ° C. or higher, preferably 180 to 260 ° C. under normal pressure or reduced pressure can be mentioned. A polymerization aid may be added at this stage. Further, in order to promote the distillation of water, toluene or the like may be added to carry out the reaction.

The amount of water in the polymerization system in the polymerization reaction is preferably 0.5 to 10.0 mol per 1 mol of the charged sulfidizing agent. Here, the amount of water in the polymerization system is the amount obtained by subtracting the amount of water removed from the polymerization system from the amount of water charged in the polymerization system. Further, the water to be charged may be in any form such as water, an aqueous solution, and water of crystallization.

[Polymerization reaction step]
It is preferable to produce a PPS resin by reacting a sulfidizing agent and a polyhalogenated aromatic compound in an organic polar solvent within a temperature range of 200 to 290 ° C.

When starting the polymerization reaction step, a sulfidizing agent and a polyhalogenated aromatic compound are added to the organic polar solvent in a temperature range of preferably room temperature to 220 ° C., preferably 100 to 220 ° C. in an inert gas atmosphere. A polymerization aid may be added at this stage. The order in which these raw materials are charged is not particularly limited and may be at the same time.

Such a mixture is usually heated to the range of 200 ° C to 290 ° C. The rate of temperature rise is not particularly limited, but a rate of 0.01 to 5 ° C./min is usually selected, and a range of 0.1 to 3 ° C./min is more preferable.

In general, the temperature is finally raised to a temperature of 250 to 290 ° C., and the reaction is carried out at that temperature for usually 0.25 to 50 hours, preferably 0.5 to 20 hours.

A method of reacting at 200 ° C. to 260 ° C. for a certain period of time and then raising the temperature to 270 to 290 ° C. before reaching the final temperature is effective in obtaining a higher degree of polymerization. At this time, the reaction time at 200 ° C. to 260 ° C. is usually selected in the range of 0.25 hours to 20 hours, preferably in the range of 0.25 to 10 hours.

In order to obtain a polymer having a higher degree of polymerization, it is effective to carry out the polymerization in a plurality of steps. When polymerizing in a plurality of steps, it is effective to move to the next step when the conversion rate of the polyhalogenated aromatic compound in the system at 245 ° C. reaches 40 mol% or more, preferably 60 mol%. Is.

[Recovery process]
After completion of the polymerization, a solid substance is recovered from the polymerization reaction product containing a polymer, a solvent and the like.

The preferred recovery method for the PPS resin is to carry out under quenching conditions, and one preferred recovery method is the flash method. In the flash method, the polymerization reaction product is flushed from a high temperature and high pressure (usually 250 ° C. or higher, 8 kg / cm ² or higher) into an atmosphere of normal pressure or reduced pressure, and the polymer is made into powder or granular material at the same time as the solvent is recovered. This is a recovery method, and the term “flash” as used herein means that the polymerization reaction product is ejected from a nozzle. Specific examples of the flashing atmosphere include nitrogen or water vapor under normal pressure, and the temperature thereof is usually selected in the range of 150 ° C. to 250 ° C.

The flash method is an economical recovery method because the solid matter can be recovered at the same time as the solvent is recovered and the recovery time can be relatively short. In this recovery method, ionic compounds typified by Na and organic low-degree-of-polymerization substances (oligomers) tend to be easily incorporated into the polymer during the solidification process.

However, the method for recovering the PPS resin used in the production method of the present invention is not limited to the flash method, and any method that satisfies the requirements of the present invention is a method of slowly cooling to recover the particulate polymer. (Quench method) may be used. However, from the viewpoint of economy and performance, it is more preferable to use the PPS resin recovered by the flash method.

[Washing process]
The present invention preferably includes a step of washing the polymer obtained through the above-mentioned pre-step, polymerization reaction step, and recovery step under specific conditions. The washing steps are (1) washing the polymer obtained by polymerization with hot water at 80 to 200 ° C. at least once, (2) separating the filtrate and the polymer by filtering, and (3) separation. This is a step of immersing the polymer in one or more aqueous solutions selected from an aqueous solution containing an alkali metal, an aqueous solution containing an alkaline earth metal, or hot water, and washing the polymer at 80 to 200 ° C. at least once. Each step will be described in detail below.

(1) Step of washing the polymer obtained by polymerization with hot water at 80 to 200 ° C. at least once. The water used for the hot water treatment in the present invention is preferably distilled water or deionized water, but hot water. Alkaline metal hydroxide or the like may be added so that the pH after the treatment becomes alkaline. In particular, when the pH during hot water treatment is 10 or more, the removal rate of impurities having a carboxylic acid terminal is high, and it is easy to reduce volatile components during heat treatment, which is preferable. Further, the hot water treatment temperature needs to be 80 to 200 ° C., preferably 120 to 200 ° C., more preferably 150 to 200 ° C. If the temperature is lower than 80 ° C, the effect of hot water treatment is small and the amount of volatile components increases, and if the temperature exceeds 200 ° C, the pressure becomes too high, which is not preferable for safety.

The hot water treatment time is preferably a time when the extraction treatment with PPS resin and hot water is sufficient, for example, 2 to 24 hours when the treatment is performed at 80 ° C., and 0.01 to 0.01 when the treatment is performed at 200 ° C. 5 hours is preferred.

The ratio of PPS resin to water in the hot water treatment is preferably treated in a state where the PPS resin is sufficiently immersed in water, and 0.5 to 500 L of water is preferably 1 to 100 L with respect to 500 g of PPS resin. Is more preferable, and 2.5 to 20 L is further preferable. If the amount of water is less than 0.5 L with respect to 500 g of the PPS resin, the PPS resin is not sufficiently immersed in the water, resulting in poor cleaning and an increase in volatile components, which is not preferable. Further, if the amount of water exceeds 500 L with respect to 500 g of the PPS resin, the amount of water with respect to the PPS resin becomes large and the production efficiency is significantly lowered, which is not preferable.

The operation of these hot water treatments is not particularly limited, and is carried out by a method of adding a predetermined amount of PPS resin to a predetermined amount of water, heating and stirring in a pressure vessel, a method of continuously performing hot water treatment, and the like. ..

Further, it is also one of the preferable embodiments that impurities are reduced in advance by washing with water of less than 80 ° C. and filtering before hot water treatment.

(2) Step of separating the filtrate and the polymer by filtering In the present invention, it is indispensable to perform filtration after washing with hot water in the above step (1) to separate the filtrate and the polymer. The filtration method is not particularly limited, but filtration using a sieve or a filter is convenient, and methods such as natural filtration, pressure filtration, vacuum filtration, and centrifugal filtration can be exemplified. Further, in order to remove impurities remaining on the surface of the PPS resin separated by filtration, it is preferable to wash with water or warm water several times. The cleaning method is not particularly limited, but the aqueous solution and the PPS resin can be filtered by sprinkling water on the PPS resin on the filtration device, or by adding the separated PPS resin to the water prepared in advance and then filtering again. The method of separating the above can be exemplified. The water used for washing is preferably distilled water or deionized water.

(3) A step of immersing the separated polymer in one or more aqueous solutions selected from an aqueous solution containing an alkali metal, an aqueous solution containing an alkaline earth metal, or hot water and washing the separated polymer at 80 to 200 ° C. at least once. Then, after the separation in the above step (2) is performed, the separated polymer is immersed in one or more aqueous solutions selected from an aqueous solution containing an alkali metal, an aqueous solution containing an alkaline earth metal, or hot water for 80 to 200. It is necessary to wash at least once at ° C. The cleaning temperature is preferably 120 to 200 ° C, more preferably 150 to 200 ° C. By going through this step, impurities in the polymer can be reduced to an extremely low level, and volatile components generated during molding can be significantly reduced. Further, in cleaning with hot water, more stable moldability can be ensured by introducing I-valent metal ions into PPS, which is a more preferable cleaning method. If the cleaning temperature is less than 80 ° C., the removal of volatile components becomes insufficient, and when cleaning with hot water, the introduction of metal ions into the PPS becomes insufficient. If the temperature exceeds 200 ° C., the pressure becomes too high, which is not preferable for safety.

The cleaning treatment time is, for example, preferably 2 to 24 hours when the treatment is performed at 80 ° C., and 0.01 to 5 hours when the treatment is performed at 200 ° C.

The ratio of the PPS resin to water during the cleaning treatment is preferably treated in a state where the PPS resin is sufficiently immersed in water, and 0.5 to 500 L of water is preferable with respect to 500 g of the PPS resin, and 1 to 1 100 L is more preferable, and 2.5 to 20 L is even more preferable. If the amount of water is less than 0.5 L with respect to 500 g of the PPS resin, the PPS resin is not sufficiently immersed in the water, resulting in poor cleaning. Further, if the amount of water exceeds 500 L with respect to 500 g of the PPS resin, the amount of water with respect to the PPS resin becomes large and the production efficiency is significantly lowered, which is not preferable.

These cleaning treatment operations are not particularly limited, and are carried out by a method of adding a predetermined amount of PPS resin to a predetermined amount of aqueous solution or water, heating and stirring in a pressure vessel, a method of continuously performing the treatment, and the like. The water used for washing is preferably distilled water or deionized water.

Examples of the alkali metal in the aqueous solution containing the alkali metal used for the cleaning treatment include Li, Na, and K, and examples of the alkaline earth metal in the aqueous solution containing the alkaline earth metal include Ca, Mg, and Ba. These metal components are dispersed in an aqueous solution as metal ions, and are added to water in the form of water-soluble salts having acetate ions, halide ions, hydroxide ions and carbonate ions as counter anions to form an aqueous solution. It is preferable to do so. Specific suitable water-soluble salts include Ca acetate, Mg acetate, Ca chloride, Ca bromide, Ca carbonate, Ca hydroxide, Na acetate, K acetate, Na carbonate, K carbonate and the like, which are inexpensive and good. Ca acetate and Na acetate are more preferable as the water-soluble salt capable of obtaining a sufficient antifreeze resistance. The concentration of the water-soluble salt with respect to water is preferably about 0.001 to 5% by weight.

After the main step (3), it is preferable to separate the filtrate and the polymer by filtration in the same manner as in the step (2), and several times with water or warm water to remove impurities remaining on the surface of the PPS resin after the separation. It is preferable to wash.

In all of the above-mentioned cleaning steps (1) to (3) in the present invention, it is preferable that the place where the PPS is treated exceeds pH 8 in order to obtain excellent heat-resistant water and antifreeze resistance. When the pH is 8 or less, the melt crystallization temperature of the PPS resin exceeds 210 ° C., and therefore, due to the high melt crystallization temperature, problems such as unfilling are likely to occur during molding of thin-walled molded products. If the pH exceeds 8, excellent heat-resistant water and antifreeze resistance can be ensured. Therefore, if the place where PPS is treated is within the range exceeding pH 8, acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, silicic acid, carbonic acid and propionic acid There is no problem even if the treatment is carried out by appropriately adding an acid such as, or an aqueous solution containing an acid. Further, since decomposition of the PPS terminal group is not preferable in the above steps (1) to (3), it is desirable to set the atmosphere in the step to an inert atmosphere. Examples of the inert atmosphere include nitrogen, helium, and argon, but a nitrogen atmosphere is preferable from the viewpoint of economy.

The present invention may include a step of washing with an organic solvent before the step (1), the method of which is as follows. The organic solvent used for cleaning the PPS resin in the present invention is not particularly limited as long as it does not have an action of decomposing the PPS resin. For example, N-methyl-2-pyrrolidone, dimethylformamide, dimethylacetamide, 1, Nitrogen-containing polar solvents such as 3-dimethylimidazolidinone, hexamethylphosphorasamide, and piperazinones, sulfoxide-sulfone solvents such as dimethyl sulfoxide, dimethyl sulfone, and sulfolane, and ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, and acetophenone. , Dimethyl ether, dipropyl ether, dioxane, tetrahydrofuran and other ether solvents, chloroform, methylene chloride, trichloroethylene, ethylene dichloride, perchlorethylene, monochloroethane, dichloroethane, tetrachloroethane, perchlorethane, chlorobenzene and other halogen-based solvents. Solvents, alcohol / phenol solvents such as methanol, ethanol, propanol, butanol, pentanol, ethylene glycol, propylene glycol, phenol, cresol, polyethylene glycol, polypropylene glycol and aromatic hydrocarbon solvents such as benzene, toluene and xylene. Can be mentioned. Among these organic solvents, the use of N-methyl-2-pyrrolidone, acetone, dimethylformamide, chloroform and the like is particularly preferable. Moreover, these organic solvents are used in one kind or a mixture of two or more kinds.

As a method of cleaning with an organic solvent, there is a method of immersing the PPS resin in the organic solvent, and it is also possible to appropriately stir or heat as necessary. The cleaning temperature when cleaning the PPS resin with an organic solvent is not particularly limited, and any temperature of about room temperature to 300 ° C. can be selected. The higher the cleaning temperature, the higher the cleaning efficiency tends to be, but usually, a sufficient effect can be obtained at a cleaning temperature of room temperature to 150 ° C. It is also possible to wash under pressure in a pressure vessel at a temperature higher than the boiling point of the organic solvent. In addition, there is no particular limitation on the cleaning time. Although it depends on the cleaning conditions, in the case of batch-type cleaning, a sufficient effect is usually obtained by cleaning for 5 minutes or more. It is also possible to wash continuously.

[Heat treatment process]
In the present invention, it is preferable to perform heat treatment after the above cleaning step because a PPS resin having high mechanical strength and excellent antifreeze resistance can be obtained. The heat treatment process will be specifically described below.

In the present invention, it is preferable to perform heat treatment in order to obtain a PPS resin having high mechanical strength, but excessive heat treatment causes unfilling during molding due to a decrease in melt fluidity and an increase in gelled product in the resin. It is not preferable because it causes the above. However, if the heat treatment is too light, the effect of reducing volatile components is small, and the strength of the resin tends to decrease. According to the heat treatment of the present invention, it is possible to obtain a PPS resin having improved mechanical strength while suppressing the generation of gelled products without impairing the melt fluidity.

The heat treatment may be performed in a high oxygen concentration atmosphere or a low oxygen concentration atmosphere as long as the heat treatment temperature and the heat treatment time are set within a specific range, but the heat treatment in a low oxygen concentration atmosphere is preferable.

As a condition of a high oxygen concentration atmosphere, the oxygen concentration is preferably a concentration exceeding 2% by volume, the heat treatment temperature is 160 to 270 ° C., and the heat treatment time is preferably 0.1 to 17 hours. However, under the condition of high oxygen concentration, the reduction rate of the volatile component is fast, but at the same time, the oxidative cross-linking progresses rapidly, so that gelled products are likely to be generated. Therefore, it is generally preferable to perform the heat treatment at a low temperature for a long time or at a high temperature for a short time. Specific conditions for low-temperature and long-term heat treatment are preferably 160 ° C. or higher and 210 ° C. or lower for 1 hour or longer and 17 hours or lower, and more preferably 170 ° C. or higher and 200 ° C. or lower for 1 hour or longer and 10 hours or lower. Even if the heat treatment is performed at a temperature below 160 ° C., the effect of reducing volatile components is small and the effect of improving mechanical strength is small. Further, even at a low temperature, under the condition of an oxygen concentration of more than 2% by volume, if the heat treatment time exceeds 17 hours, oxidative cross-linking proceeds and gelled products are likely to be generated. Specific conditions for high-temperature and short-time heat treatment are preferably 0.1 hour or more and less than 1 hour at 210 ° C. or higher and 270 ° C. or lower, and more preferably 0.2 to 0.8 hours at 220 ° C. or higher and 260 ° C. or lower. .. When the heat treatment temperature exceeds 270 ° C., oxidative cross-linking progresses rapidly and gelled products are likely to be generated. Further, even at a high temperature, if the heat treatment time is less than 0.1 hour, the effect of reducing volatile components is small and the effect of improving mechanical strength is small.

As a condition of a low oxygen concentration atmosphere, the oxygen concentration is preferably 2% by volume or less, the heat treatment temperature is preferably 210 to 270 ° C., and the heat treatment time is preferably 0.2 to 50 hours. When the oxygen concentration is low, the effect of reducing volatile components tends to be small, so it is generally preferable to carry out the heat treatment at a high temperature for a long time, and it is possible to carry out the heat treatment under the heat treatment temperature condition of 220 ° C. to 260 ° C. for 2 to 20 hours. More preferred. When the heat treatment time is less than 210 ° C., the volatile components are not reduced and the effect of improving the mechanical strength is small, and when the heat treatment time exceeds 50 hours, the productivity is lowered.

The heating device for the heat treatment of the present invention may be a normal hot air dryer or a rotary type or a heating device with a stirring blade, but in the case of efficient and more uniform treatment, the rotary type or the heating device may be used. It is more preferable to use a heating device with a stirring blade, and examples thereof include a paddle type dryer, a fluidized layer dryer, a KID dryer, a steam tube dryer, an inclined disc dryer, a hopper dryer, and a vertical stirring dryer. Of these, paddle type dryers, fluidized bed dryers, and KID dryers are preferable for uniform and efficient heating. In order to adjust the oxygen concentration of the heat treatment, there is no problem even if a non-oxidizing inert gas such as nitrogen, argon, helium or steam is mixed with an oxidizing gas such as oxygen, air or ozone. As long as the heat treatment can be performed in the heating device, there is no particular limitation on introducing the oxidizing gas or the inert gas from any position on the upper, lower or side surface of the heating device, but a simpler method is the upper part of the heating device. Introducing gas from. Further, the oxidizing gas and the inert gas may be mixed before the introduction of the heating device and then introduced into the device, or the oxidizing gas and the inert gas may be separately mixed from different places in the heating device. .. It is considered that the structure of the PPS resin has changed through the heat treatment step, but there are circumstances in which it is not practical to specify the structure of the PPS resin. By going through the heat treatment step, volatile components and water can be removed, and a PPS resin having excellent mechanical strength and weld strength can be obtained.

The melt flow rate (hereinafter, sometimes abbreviated as MFR) of the PPS resin obtained through the polymerization reaction step, the recovery step, preferably the washing step, and the heat treatment step is preferably 500 g / 10 minutes or less. It is 400 g / 10 minutes or less, more preferably 300 g / 10 or less. If the MFR exceeds 500 g / 10 minutes, the degree of polymerization is too low and the mechanical strength is lowered. The lower limit is preferably in the range of more than 80 g / 10 minutes, preferably 100 g / 10 minutes or more from the viewpoint of moldability. Here, MFR is a value measured according to ASTM-D1238-70 at a measurement temperature of 315.5 ° C. and a load of 5000 g.

The PPS resin obtained through the heat treatment is a polymer having a complicated and diverse structure, and it is impossible or impractical to directly specify it by a general formula (structure) or characteristics. It becomes possible to specify for the first time by a manufacturing method (heat treatment) for obtaining a PPS resin such as.

Above all, the PPS resin having the following characteristics (1) and (2) is preferable in the sense of obtaining high weld strength.

(1) The amount of gas generated when heated and melted at 320 ° C. for 2 hours under vacuum is 0.3% by weight or less, preferably 0.28% by weight or less, and more preferably 0.22% by weight or less. It is desirable to have. A PPS resin having such properties can be obtained by appropriately applying the above-mentioned cleaning and thermal oxidation treatment. It is preferable to reduce the amount of gas generated to 0.3% by weight or less because the volatile components are reduced and the weld strength and antifreeze resistance are improved. The lower limit of the amount of gas generated after the thermal oxidation treatment is preferably small, but the preferable lower limit is 0.01% by weight. By setting it to 0.01% by weight or more, it is possible to prevent the thermal oxidation treatment time from becoming too long and to prevent it from becoming economically disadvantageous. Further, it is also preferable in the sense of preventing the gelled product from being easily formed due to the prolongation of the thermal oxidation treatment time, which is one of the causes of molding defects.

The amount of gas generated means the amount of the adhesive component in which the gas volatilized when the PPS resin is heated and melted under vacuum is cooled and liquefied or solidified, and the glass in which the PPS resin is vacuum-sealed. It is measured by heating the ample in a tubular furnace. The shape of the glass ampoule is 100 mm × 25 mm for the abdomen, 255 mm × 12 mm for the neck, and 1 mm for the wall thickness. As a specific measurement method, only the body of a glass ampoule vacuum-sealed with PPS resin is inserted into a tube furnace at 320 ° C. and heated for 2 hours, so that the ampoule is volatile at the neck of the ampoule that is not heated by the tube furnace. The gas is cooled and adheres. After cutting out the neck and weighing it, the adhering gas is dissolved in chloroform and removed. The neck is then dried and then weighed again. The amount of gas generated is calculated from the weight difference between the ampoule necks before and after the gas is removed.

(2) The amount of residue when dissolved in 20 times by weight of 1-chloronaphthalene at 250 ° C. for 5 minutes and subjected to hot pressure filtration with a PTFE membrane filter having a pore size of 1 μm is 4.0% by weight or less, preferably 3. It is preferably 5.5% by weight or less, more preferably 3.0% by weight or less. It is preferable that the amount of the residue is 4.0% by weight or less because the volatile components are reduced and the weld strength is improved. The lower limit of the residual amount is not particularly limited, but is preferably 1.5% by weight or more, preferably 1.7% by weight or more. By setting the amount of the residue to 1.5% by weight or more, it is possible to obtain the effect of advancing the cross-linking by the thermal oxidation treatment and reducing the volatile components at the time of melting. A PPS resin having such properties can be obtained by appropriately applying the above thermal oxidation treatment.

The amount of the residue is measured by using a PPS resin pressed film having a thickness of about 80 μm as a sample and using a SUS test tube equipped with a high-temperature filtration device, a pneumatic cap and a collection funnel. Specifically, first, a membrane filter having a pore size of 1 μm is set in a SUS test tube, and then a press film-formed PPS resin having a thickness of about 80 μm and 1-chloronaphthalene having a weight of 20 times are weighed and sealed. This is set in a high temperature filtration device at 250 ° C. and heated and shaken for 5 minutes. Next, a syringe containing air is connected to the pneumatic cap, and then the piston of the syringe is pushed out to perform thermal filtration by pneumatic pressure. As a specific method for quantifying the amount of residue, it is determined from the weight difference between the membrane filter before filtration and the membrane filter vacuum dried at 150 ° C. for 1 hour after filtration.

For example, by adopting the above-mentioned production method, it is possible to obtain a PPS resin suitable for a PPS resin composition having excellent mechanical strength and fluidity, and the heat treatment according to the present invention. It is preferable to use the PPS resin obtained. It is preferable to blend such a (A) PPS resin as a PPS resin to be blended in the PPS resin composition of the present invention, but by using at least 20% by weight of the PPS resin as such a PPS resin, PPS The resin composition can be provided with excellent mechanical strength and fluidity. It is preferable that at least 30% by weight of the PPS resin blended in the PPS resin composition is such a PPS resin, and more preferably 50% by weight or more.

The PPS resin composition of the present invention comprises 60 to 100 parts by weight of (B) glass fiber, and (B) glass fiber (B-1) and (B-2) milled glass fiber are used as the glass fiber. Mix. The blending amount of (B-1) glass fiber and (B-2) milled glass fiber in the PPS resin composition of the present invention is (B-1) glass with respect to 100 parts by weight of (A) polyphenylene sulfide resin. The fiber is 30 to 50 parts by weight, and the (B-2) milled glass fiber is 30 to 50 parts by weight. By blending (B-1) glass fiber and (B-2) milled glass fiber in this ratio, it is preferable in terms of obtaining excellent mechanical strength, weld strength, and dimensional accuracy, and more preferably (B-). 1) The glass fiber is 35 to 45 parts by weight, and (B-2) the milled glass fiber is 35 to 45 parts by weight.

The number average fiber length of the glass fibers in the PPS resin composition of the present invention is 100 to 200 μm, more preferably 110 to 190 μm. When the thickness is 100 μm or more, excellent mechanical strength can be obtained. Further, when the thickness is 200 μm or less, both excellent weld strength and fluidity can be achieved at the same time. The method for adjusting the number average fiber length of the glass fibers in the PPS resin composition is not particularly limited, and for example, (B-1) glass fibers and (B-2) milled glass fibers are used in the above proportions. Examples thereof include a method of blending in and supplying the mixture to a twin-screw extruder for kneading. The number average fiber length of the glass fibers can be calculated by the following method. First, the polyphenylene sulfide resin composition is heated in a muffle furnace at 600 ° C. for 1 to 3 hours to decompose organic substances. The remaining glass fibers are then transferred to a glass petri dish and water is used to disperse the glass fibers on the surface of the petri dish. Next, the fiber lengths of 500 or more glass fibers dispersed on the surface of the petri dish are measured using a stereomicroscope and averaged to calculate the number average fiber length of the glass fibers.

Specific examples of the (B-1) glass fiber include glass fiber, glass flat fiber, irregular cross-section glass fiber, glass cut fiber, flat glass fiber, and the like, and two or more of these may be used in combination. It is possible. Of these, glass fiber is preferable. Further, when these glass fibers are pretreated with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organic borane compound and an epoxy compound, more excellent mechanical strength is obtained. It is preferable in terms of meaning, and it is particularly preferable to treat with a converging agent containing an epoxy group.

Specific examples of the glass fiber used for the (B-2) milled glass fiber include glass fiber, glass flat fiber, irregular cross-section glass fiber, glass cut fiber, flat glass fiber, and the like. It is also possible to use two or more types together. Of these, glass fiber is preferable. Further, when these glass fibers are pretreated with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organic borane compound and an epoxy compound, more excellent mechanical strength is obtained. It is preferable in terms of meaning, and it is particularly preferable to treat with a converging agent containing an epoxy group.

The (B-2) milled glass fiber can be obtained by pulverizing the glass fiber exemplified above by a known pulverization method. The production method is not particularly limited, but it can be obtained by, for example, crushing with a crusher such as a fret mill, a jet mill, or a ball mill, and classifying by a sieve or the like.

The fiber diameter of the glass fiber (B) is preferably 9.0 to 14.0 μm. Within this range, excellent mechanical strength and dimensional accuracy can be obtained.

The blending amount of (C) calcium carbonate in the PPS resin composition of the present invention is (C) 80 to 120 parts by weight of calcium carbonate with respect to 100 parts by weight of (A) PPS resin. With such a blending amount, excellent fluidity and dimensional accuracy can be made parallel.

If the amount of calcium carbonate (C) is less than 80 parts by weight with respect to 100 parts by weight of the (A) PPS resin, appropriate dimensional accuracy as a composition cannot be obtained, which is not preferable. If the amount of calcium carbonate (C) exceeds 120 parts by weight, the melt fluidity of the composition is lowered, appropriate molding processability cannot be obtained, and mechanical strength cannot be obtained, which is not preferable.

Specific examples of (C) calcium carbonate include heavy calcium carbonate and synthetic calcium carbonate, with heavy calcium carbonate being preferable. Further, these calcium carbonates may be pretreated with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organic borane compound and an epoxy compound before use.

Further, in the present invention, it is preferable to use (B) glass fiber and (C) calcium carbonate in combination in order to achieve both excellent mechanical strength, dimensional accuracy, and cold thermal impact resistance. The ratio of these blending amounts is in the range of (B) / (C) = 1/1 (weight ratio) to 1 / 1.25 (weight ratio), which has excellent mechanical strength, dimensional accuracy, and cold thermal impact resistance. It is more preferable to achieve both.

In the PPS resin composition of the present invention, an elastomer may be added for the purpose of improving the thermal impact resistance as long as the effects of the present invention are not impaired. As the (D) elastomer, α-olefins such as ethylene, propylene, 1-butene, 1-pentene, 1-octene, 4-methyl-1-pentene, and isobutylene can be obtained by copolymerizing one or two or more kinds of α-olefins (1). Co) Copolymers, for example, ethylene / propylene copolymers (“/” represents copolymers, the same applies hereinafter), ethylene / 1-butene copolymers, ethylene / 1-hexene copolymers, ethylene / 1-octenes. Copolymers can be mentioned. Further, α-olefin and α, β-unsaturated acid such as acrylate, methyl acrylate, ethyl acrylate, butyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate and its alkyl ester are used. Copolymers such as ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / butyl acrylate copolymer, ethylene / methyl methacrylate copolymer, ethylene / ethyl methacrylate copolymer , Ethylene / butyl methacrylate copolymer, etc., can be obtained by introducing a monomer component having an epoxy group (functional group-containing component). Examples of the functional group-containing component include glycidyl acrylate and methacrylic acid. Examples thereof include monomers containing an epoxy group such as glycidyl, glycidyl etacrylate, glycidyl itacone, and glycidyl citracone. The method for introducing these functional group-containing components is not particularly limited, and the olefin-based (co) polymer may be copolymerized when (co-) polymerized, or the olefin-based (co) polymer may be graft-introduced using a radical initiator. You can use a method such as making it. The amount of the functional group-containing component introduced is preferably in the range of 0.001 to 40 mol%, preferably 0.01 to 35 mol%, based on all the monomers constituting the modified olefin-based (co) polymer. Appropriate. Specific examples of the olefin-based copolymer having a glycidyl group obtained by introducing a monomer component having an epoxy group into a particularly useful olefin polymer include an ethylene / propylene-g-glycidyl methacrylate copolymer ("". "G" represents a graft, the same applies hereinafter), ethylene / 1-butene-g-glycidyl methacrylate copolymer, ethylene / glycidyl methacrylate copolymer, ethylene / glycidyl methacrylate copolymer, ethylene / methyl acrylate / In addition to glycidyl methacrylate copolymers, ethylene / methyl methacrylate / glycidyl methacrylate copolymers, or glycidyl esters of α-olefins such as ethylene and propylene and α, β-unsaturated acids, and other monomers. An epoxy group-containing olefin-based copolymer containing the above as an essential component is also preferably used.

Preferred examples include ethylene / glycidyl methacrylate copolymer, ethylene / methyl acrylate / glycidyl methacrylate copolymer, ethylene / methyl methacrylate / glycidyl methacrylate copolymer and the like. Particularly preferred are ethylene / methyl acrylate / glycidyl methacrylate copolymers.

The blending amount of the elastomer (D) is preferably 1 to 10 parts by weight, and more preferably 2 to 8 parts by weight in order to achieve both excellent mechanical strength, cold and thermal impact resistance, and moldability.

Further, the PPS resin composition of the present invention contains an epoxy group, an amino group, an isocyanate group, a hydroxyl group, a mercapto group and a ureido group for the purpose of improving mechanical strength, toughness and the like without impairing the effects of the present invention. A silane compound having at least one functional group selected from the above may be added. Specific examples of such compounds include epoxy group-containing alkoxysilane compounds such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. , Γ-Mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane and other mercapto group-containing alkoxysilane compounds, γ-ureidopropyltriethoxysilane, γ-ureidopropyltrimethoxysilane, γ- (2-ureidoethyl) amino Ureid group-containing alkoxysilane compounds such as propyltrimethoxysilane, γ-isocyanatepropyltriethoxysilane, γ-isocyanatepropyltrimethoxysilane, γ-isocyanatepropylmethyldimethoxysilane, γ-isocyanatepropylmethyldiethoxysilane, γ-isocyanatepropyl Isocyanate group-containing alkoxysilane compounds such as ethyldimethoxysilane, γ-isocyanatepropylethyldiethoxysilane, γ-isocyanatepropyltrichlorosilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) Contains amino group-containing alkoxysilane compounds such as aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane and γ-aminopropyltriethoxysilane, and hydroxyl groups such as γ-hydroxypropyltrimethoxysilane and γ-hydroxypropyltriethoxysilane. Examples thereof include alkoxysilane compounds. Of these, an epoxysilane having an epoxy group, an amino group, an isocyanate group, and a hydroxyl group is particularly suitable for obtaining excellent weld strength. The suitable amount of the silane compound added is selected in the range of 0.05 to 3 parts by weight with respect to 100 parts by weight of the PPS resin.

Further, the PPS resin composition of the present invention may be further blended with other resins as long as the effects of the present invention are not impaired. The blendable resin is not particularly limited, and specific examples thereof include polyamide resins such as nylon 6, nylon 66, nylon 610, nylon 11, nylon 12, and aromatic nylon, polyethylene terephthalate, and polybutylene terephthalate. Polycyclohexyl dimethylene terephthalate, polyester resin such as polynaphthalene terephthalate, polyamide-imide, polyacetal, polyimide, polyetherimide, polyethersulfone, modified polyphenylene ether resin, polysulfone resin, polyallyl sulfone resin, polyketone resin, polyallylate resin, Examples thereof include liquid crystal polymers, polyether ketone resins, polythioether ketone resins, polyether ether ketone resins, polyamide-imide resins, and tetrafluoride polyethylene resins. In the present invention, other resin components that also correspond to the (D) elastomer are treated as the (D) elastomer.

The PPS resin composition of the present invention contains other components, for example, antistatic agents and heat-resistant stabilizers (hindered phenol-based, hydroquinone-based, phosphorus-based, phos) other than the above, as long as the effects of the present invention are not impaired. Fight-based, amine-based, sulfur-based and their substitutes, etc.), weather-resistant agents (resorcinol-based, salicylate-based, benzotriazole-based, benzophenone-based, hindered amine-based, etc.), mold release agents and lubricants (montanoic acid and metal salts thereof, etc.) The ester, its half ester, stearyl alcohol, stearamide, stealth, bisurea, polyethylene wax, etc.), pigments (cadmium sulfide, phthalocyanine, carbon black for coloring, etc.), dyes (niglosin, etc.), crystal nucleating agents (talc, silica) , Kaolin, clay, etc.), plasticizers (octyl p-oxybenzoate, N-butylbenzenesulfonamide, etc.), antistatic agents (alkylsulfate-type anionic antistatic agents, quaternary ammonium salt-type cationic antistatic agents, etc. Nonionic antistatic agents such as polyoxyethylene sorbitan monostearate, betaine amphoteric antistatic agents, flame retardants (eg, red phosphorus, phosphoric acid esters, melamine cyanurates, magnesium hydroxide, aluminum hydroxide, etc.) Hydroxide, ammonium polyphosphate, brominated polystyrene, brominated polyphenylene ether, brominated polycarbonate, brominated epoxy resin or a combination of these brominated flame retardants and antimony trioxide, etc.), heat stabilizer, calcium stearate, stearer Lubricants such as aluminum acetate and lithium stearate, bisphenol epoxy resins such as bisphenol A type, strength improvers such as novolak phenol type epoxy resin, cresol novolac type epoxy resin, antistatic agents, colorants, flame retardants and foaming agents Ordinary additives can be added.

The PPS resin composition of the present invention may be used by further adding other inorganic fillers other than (B) glass fiber and (C) calcium carbonate as long as the effects of the present invention are not impaired. The inorganic filler that can be added is not particularly limited, and specific examples of the fibrous filler as the inorganic filler include stainless fibers, aluminum fibers, brass fibers, rock wool, PAN-based and pitch-based carbon fibers. Carbon nanotubes, carbon nanofibers, calcium carbonate whisker, wallastenite whisker, potassium titanate whisker, barium titanate whisker, aluminum borate whisker, silicon nitride whisker, aramid fiber, alumina fiber, silicon carbide fiber, asbestos fiber, gypsum fiber, ceramic Examples thereof include fibers, zirconia fibers, silica fibers, titanium oxide fibers, silicon carbide fibers, and the like, and two or more of these can be used in combination. Further, it is more excellent mechanical strength to use these fibrous fillers by pretreating them with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organic borane compound and an epoxy compound. It is preferable in the sense of obtaining.

Specific examples of the non-fibrous filler as the inorganic filler include talc, wallastenite, zeolite, sericite, mica, kaolin, clay, pyrophyllite, bentonite, asbestos, alumina silicate, and hydrotalcite. Silate, silicon oxide, magnesium oxide, aluminum oxide (alumina), silica (crushed / spherical), quartz, glass beads, glass flakes, crushed / amorphous glass, glass microballoons, molybdenum disulfide, aluminum oxide (crushed) (Shape), translucent alumina (fibrous / plate / scale / granular / amorphous / crushed), titanium oxide (crushed), zinc oxide (fibrous / plate / scale / granular / amorphous / Oxides such as crushed products), carbonates such as magnesium carbonate and zinc carbonate, sulfates such as calcium sulfate and barium sulfate, hydroxides such as calcium hydroxide, magnesium hydroxide and aluminum hydroxide, silicon carbide, carbon black And silica, graphite, aluminum oxide, translucent aluminum nitride (fibrous / plate / scaly / granular / amorphous / crushed), calcium polyphosphate, graphite, metal powder, metal flakes, metal ribbon, metal oxide, etc. Here, specific examples of metal powders, metal flakes, and metal types of metal ribbons include silver, nickel, copper, zinc, aluminum, stainless steel, iron, brass, chromium, and tin. Further, carbon powder, graphite, carbon flakes, scaly carbon, fullerene, graphene and the like may be mentioned, and these may be hollow, and two or more kinds of these fillers can be used in combination. Further, these inorganic fillers may be pretreated with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organic borane compound and an epoxy compound before use.

The method for preparing the PPS resin composition of the present invention is not particularly limited, but each raw material is supplied to a commonly known melt mixer such as a single-screw or twin-screw extruder, a Banbury mixer, a kneader and a mixing roll, and is 280 to 280. A typical example is a method of kneading at a temperature of 380 ° C. The mixing order of the raw materials is not particularly limited, and all the raw materials are blended and then melt-kneaded by the above method, some raw materials are blended and then melt-kneaded by the above method, and the remaining raw materials are blended and melt-kneaded. Any method may be used, such as a method of mixing a part of the raw materials and then mixing the remaining raw materials with a side feeder during melt-kneading with a single-screw or twin-screw extruder. Further, as for the small amount additive component, it is of course possible to knead other components by the above method or the like to pelletize them, and then add them before molding and use them for molding.

The PPS resin composition of the present invention thus obtained can be used for various moldings such as injection molding, extrusion molding, blow molding, and transfer molding, and is particularly suitable for injection molding applications.

As described above, the PPS resin composition of the present invention is not only excellent in mechanical strength, but also excellent in dimensional accuracy, weld strength, and cold thermal impact resistance in a balanced manner. That is, the PPS resin composition of the present invention has properties of high mechanical strength, dimensional accuracy, weld strength, and excellent cold and thermal impact resistance, and is therefore useful for all automobile parts, and in particular, a plurality of PPS resin compositions. It is useful for small, complicated, and thin-walled insert metal-encapsulated molded products that combine parts.

Other applicable uses of the PPS resin composition of the present invention include, for example, sensors, LED lamps, consumer connectors, sockets, resistors, relay cases, switches, coil bobbins, capacitors, variable condenser cases, oscillators, and various terminal boards. , Transformers, plugs, printed circuit boards, tuners, speakers, microphones, headphones, small motors, magnetic head bases, semiconductors, liquid crystal, FDD carriages, FDD chassis, motor brush holders, parabolic antennas, computer-related parts, etc.・ Electronic parts: VTR parts, TV parts, irons, hair dryers, rice cooker parts, microphone parts, acoustic parts, audio / laser discs (registered trademark) ・ Audio equipment parts such as compact discs, lighting parts, refrigerator parts, air conditioners It can also be applied to household and office electrical product parts such as parts, typewriter parts, and word processor parts. Other machine-related parts such as office computer-related parts, telephone equipment-related parts, facsimile-related parts, copying machine-related parts, cleaning jigs, motor parts, writers, typewriters, etc .: microscopes, binoculars, cameras, watches, etc. Optical equipment represented by, precision machinery related parts; water faucet tops, mixing faucets, pump parts, pipe joints, water volume control valves, relief valves, hot water temperature sensors, water volume sensors, water meter housings and other water-related parts; valves Alternator terminal, alternator connector, IC regulator, potentiometer base for light deer, various valves such as exhaust gas valve, various fuel-related / exhaust system / intake system pipes, air intake nozzle snorkel, intake manifold, fuel pump, engine cooling water Joint, carburetor main body, carburetor spacer, exhaust gas sensor, cooling water sensor, oil temperature sensor, throttle position sensor, crank shaft position sensor, air flow meter, brake pad wear sensor, thermostat base for air conditioner, heating hot air flow control valve , Brush holder for radiator motor, Water pump impeller, Turbine vane, Wiper motor related parts, Dustributor, Starter switch, Starter relay, Wire harness for transmission, Window washer nozzle, Air conditioner panel switch board, Fuel related electromagnetic valve coil, Automotive / vehicle related products such as fuse connectors, horn terminals, insulation plates for electrical components, step motor rotors, lamp sockets, lamp reflectors, lamp housings, brake pistons, solenoid bobbins, engine oil filters, ignition device cases, vehicle speed sensors, cable liners, etc. Various uses such as parts can be exemplified.

Examples will be shown below and the present invention will be described in more detail, but the present invention is not limited to the description of these examples.

[Measuring method of PPS resin]
(1) Gas generation amount
3 g of PPS resin was weighed into a glass ampoule having an abdomen of 100 mm × 25 mm, a neck of 255 mm × 12 mm, and a wall thickness of 1 mm, and then vacuum-sealed. Only the body of this glass ampoule was inserted into a ceramic electric tube furnace ARF-30K manufactured by Asahi Rika Seisakusho and heated at 320 ° C. for 2 hours. After removing the ampoule, the neck of the ampoule, which was not heated by the tube furnace and had volatile gas attached, was cut out with a file and weighed. Then, the adhering gas was dissolved in 5 g of chloroform to remove it, dried in a glass dryer at 60 ° C. for 1 hour, and then weighed again. The difference in weight of the ampoule neck before and after removing the gas was defined as the amount of gas generated (% by weight).

(2) Amount of residue A PTFE membrane filter with a pore size of 1 μm, which was weighed in advance, was set in a SUS test tube manufactured by Senshu Kagaku equipped with a pneumatic cap and a collecting funnel, and 100 mg of PPS resin made into a press film to a thickness of about 80 μm And 1-chloronaphthalene (2 g) were weighed and sealed. This was inserted into a high-temperature filtration device SSC-9300 manufactured by Senshu Kagaku, and the PPS resin was dissolved in 1-chloronaphthalene by heating and shaking at 250 ° C. for 5 minutes. After connecting a 20 mL syringe containing air to the pneumatic cap, the piston was extruded and the solution was filtered through a membrane filter. The membrane filter was taken out, vacuum dried at 150 ° C. for 1 hour, and then weighed. The difference in the weight of the membrane filter before and after filtration was defined as the residual amount (% by weight).

(3) Melt flow rate (MFR)
The measurement temperature was 315.5 ° C. and the load was 5000 g, and the measurement was performed according to ASTM-D1278-70.

[Reference Example 1] Polymerization of PPS (PPS-1)
In a stirrer and an autoclave with a valve on the bottom, 8267.4 g (70.0 mol) of 47.5% sodium hydrosulfide, 2925.0 g (70.2 mol) of 96% sodium hydroxide, N-methyl-2- 13860.0 g (140.0 mol) of pyrrolidone (NMP), 1894.2 g (23.1 mol) of sodium acetate, and 10500.0 g of ion-exchanged water were charged, and it took about 3 hours to reach 240 ° C. through nitrogen at normal pressure. After gradual heating to distill out 14772.1 g of water and 280.0 g of NMP, the reaction vessel was cooled to 160 ° C. The amount of residual water in the system per 1 mol of the charged alkali metal sulfide was 1.08 mol including the water consumed for the hydrolysis of NMP. The amount of hydrogen sulfide scattered was 0.023 mol per mol of the charged alkali metal sulfide.

Next, 10646.7 g (72.4 mol) of p-dichlorobenzene (p-DCB) and 6444.9 g (65.1 mol) of NMP were added, the reaction vessel was sealed under nitrogen gas, and the mixture was stirred at 240 rpm. The temperature was raised from 200 ° C. to 270 ° C. at a rate of 0.6 ° C./min and maintained at 270 ° C. for 70 minutes. The extraction valve at the bottom of the autoclave was opened, the contents were flushed into a container with a stirrer for 15 minutes while pressurizing with nitrogen, and the mixture was stirred at 250 ° C. for a while to remove most of NMP.

The obtained solid matter and 53 liters of ion-exchanged water were placed in an autoclave equipped with a stirrer, washed at 70 ° C. for 30 minutes, and then suction-filtered with a glass filter having a pore size of 10 to 16 μm. Next, 60 liters of ion-exchanged water heated to 70 ° C. was poured into a glass filter having a pore size of 10 to 16 μm, and suction filtration was performed to obtain 18,000 g of PPS resin cake (including 7550 g of PPS resin).

18,000 g of the PPS resin cake, 40 liters of ion-exchanged water, and 43 g of acetic acid were charged into an autoclave equipped with a stirrer, the inside of the autoclave was replaced with nitrogen, the temperature was raised to 192 ° C., and the temperature was maintained for 30 minutes for acid treatment. The pH at the time of acid treatment was 7. After autoclave cooling, the contents were filtered through a glass filter with a pore size of 10-16 μm. Then, 60 liters of ion-exchanged water heated to 70 ° C. was poured into a glass filter and suction filtered to obtain a cake. The obtained cake was dried at 120 ° C. for 4 hours under a nitrogen stream to obtain an acid-treated PPS resin powder. Next, this PPS resin powder was placed in a heating device with a stirrer having a volume of 100 liters and subjected to thermal oxidation treatment at 220 ° C. and an oxygen concentration of 2% for 2 hours to obtain a crosslinked PPS-1. The gas generation amount of the obtained polymer was 0.16% by weight, the residue amount was 1.9% by weight, and the MFR was 554 g / 10 minutes.

[Reference Example 2] Polymerization of PPS (PPS-2)
8.27 kg (70.00 mol) of 47.5% sodium hydrosulfide, 2.91 kg (69.80 mol) of 96% sodium hydroxide, N-methyl-2 in a 70 liter autoclave with a stirrer and bottom plug valve. -Pyrrolidone (NMP) 11.45 kg (115.50 mol) and ion-exchanged water 10.5 kg were charged and gradually heated to 245 ° C. over about 3 hours while passing nitrogen under normal pressure to 14.78 kg of water and NMP0. After distilling .28 kg, the reaction vessel was cooled to 200 ° C. The amount of residual water in the system per 1 mol of the charged alkali metal sulfide was 1.06 mol including the water consumed for the hydrolysis of NMP. The amount of hydrogen sulfide scattered was 0.02 mol per mol of the charged alkali metal sulfide.

After that, the mixture was cooled to 200 ° C., 10.48 kg (71.27 mol) of p-dichlorobenzene and 9.37 kg (94.50 mol) of NMP were added, the reaction vessel was sealed under nitrogen gas, and the reaction vessel was stirred at 240 rpm. The temperature was raised from 200 ° C. to 270 ° C. at a rate of 6 ° C./min. After reacting at 270 ° C. for 100 minutes, the bottom valve of the autoclave was opened, the contents were flushed into a container with a stirrer for 15 minutes while pressurizing with nitrogen, and the contents were stirred at 250 ° C. for a while to remove most of NMP. ..

The obtained solid matter and 76 liters of ion-exchanged water were placed in an autoclave equipped with a stirrer, washed at 70 ° C. for 30 minutes, and then suction-filtered with a glass filter. Then, 76 liters of ion-exchanged water heated to 70 ° C. was poured into a glass filter and suction filtered to obtain a cake.

The obtained cake and 90 liters of ion-exchanged water were placed in an autoclave equipped with a stirrer, and acetic acid was added so that the pH became 7. After replacing the inside of the autoclave with nitrogen, the temperature was raised to 192 ° C. and held for 30 minutes. After that, the autoclave was cooled and the contents were taken out.

After suction-filtering the contents with a glass filter, 76 liters of ion-exchanged water at 70 ° C. was poured into the contents and suction-filtered to obtain a cake. The obtained cake was dried at 120 ° C. under a nitrogen stream to obtain a dried PPS. This was heat-treated at 200 ° C. under an oxygen stream until the MFR value reached 500 g / 10 minutes to obtain a crosslinked PPS-2. The amount of gas generated by the obtained polymer was 0.39% by weight, and the amount of residue was 4.3% by weight.

[Formulations used in Examples and Comparative Examples]
The formulations used in this example and comparative examples are as follows.
(A) PPS resin PPS-1: PPS resin polymerized by the method described in Reference Example 1 PPS-2: PPS resin polymerized by the method described in Reference Example 2 (B) Glass fiber B-1: Chopped strand (Japan) T-760H manufactured by Denki Glass Co., Ltd. 3 mm long Average fiber diameter 10.5 μm)
B-2: Milled fiber (EPH80M-10A manufactured by Nippon Electric Glass Co., Ltd., average fiber length 80 μm, single fiber diameter 10.5 μm)
(C) Calcium carbonate C: Heavy calcium carbonate (KSS-1000 manufactured by Calfine Co., Ltd., average particle size 4.2 μm)
(D) Elastomer D: Ethylene, glycidyl methacrylate, methyl acrylate copolymer (Bond First 7M manufactured by Sumitomo Chemical Co., Ltd.).

[Measurement evaluation method]
The measurement and evaluation methods in this example and the comparative example are as follows.

(1) Tensile strength The measurement was performed in accordance with ISO 527-1, 2 (2012). Specifically, the measurement was performed as follows. An injection molding machine manufactured by Sumitomo Heavy Industries, Ltd., in which the PPS resin composition pellet of the present invention was dried at 130 ° C. for 3 hours using a hot air dryer, and then the cylinder temperature was set to 310 ° C. and the mold temperature was set to 145 ° C. Using a mold of type A1 test piece shape (4 mm thickness) supplied to (SE-50D) and specified in ISO20753 (2008), the average velocity of the molten resin passing through the cross-sectional area of the central parallel portion is 400 ±. Injection molding was performed under the condition of 50 mm / s to obtain a test piece. After adjusting the state of this test piece for 16 hours under the conditions of 23 ° C. and 50% relative humidity, the distance between grippers: 115 mm and the test speed: 5 mm / min under the atmosphere of 23 ° C. and 50% relative humidity. Then, the tensile strength was measured in accordance with ISO 527-1, -2 (2012).

(2) Weld strength An ATM4 dumbbell piece (1.6 mmt) 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 and a mold temperature of 135 ° C using an injection molding machine. Molded under the conditions. Ten samples for measurement were obtained, and the tensile strength was measured under the conditions of a test speed of 10 mm / min and a distance between grippers: 64 mm.

(3) Fluidity Using a spiral flow mold having a thickness of 1 mm, molding was performed under the conditions of a cylinder temperature of 320 ° C., a mold temperature of 140 ° C., an injection speed of 230 mm / sec, an injection pressure of 98 MPa, an injection time of 5 sec, and a cooling time of 15 sec. The flow length was measured (injection molding machine used: "SE-30D" manufactured by Sumitomo Heavy Industries). The larger this value, the better the fluidity.

(4) Dimensional Accuracy Using an injection molding machine (SE-100DU) manufactured by Sumitomo Heavy Industries, the molded product 1 for dimensional accuracy evaluation shown in FIG. 1 was molded. The molded product 1 is a molded product molded through a gate 2 for molding. The molding conditions were a cylinder temperature of 320 ° C., a mold temperature of 130 ° C., and other conditions were general molding conditions. The MD direction (vertical direction in the figure) and the TD direction (direction orthogonal to the MD direction) of the molded product 1 were measured at three points, and the average value was calculated. The average value measured from the actual size of the mold was subtracted, and the value divided by the actual size of the mold was used as the molding shrinkage rate. The measurement was performed using a three-dimensional dimension measuring machine manufactured by Mitutoyo Co., Ltd. in accordance with JIS B0621. The value obtained by subtracting the molding shrinkage rate in the MD direction from the molding shrinkage rate in the TD direction was defined as the dimensional accuracy. If it is smaller than 0.6%, it can be said that there is no problem in practical use, but the smaller this value is, the better the dimensional accuracy is, which is preferable. Those having a molding shrinkage of 0.5% or more and less than 0.6% were evaluated as ◯, those having a molding shrinkage of less than 0.5% were evaluated as ⊚, and those having a molding shrinkage of 0.6% or more were evaluated as x.

(5) A metal insert-molded product shown in FIG. 2 was used in which a cold-heat impact resistant metal block was installed in advance in a mold and insert-molded under the conditions of a cylinder temperature of 320 ° C. and a mold temperature of 140 ° C. After treating this at 130 ° C. × 1 hour, the treatment at −40 ° C. × 1 hour was performed once, and the cold heat treatment was repeated, and the presence or absence of cracks was visually confirmed every 5 times. The number of cold heat treatments in which cracks were observed was defined as cold thermal shock resistance. If cracks do not occur 30 times or more, it can be said that there is no problem in practical use, but the more the number of treatments until cracks occur, the better the cold and thermal impact resistance, which is preferable.

(6) Number of glass fibers Average fiber length The obtained PPS resin composition was heated in a muffle furnace at 600 ° C. for 1 to 3 hours to decompose organic substances. The remaining glass fibers were then transferred to a glass petri dish and water was used to disperse the glass fibers on the surface of the petri dish. The number average fiber length of the glass fibers in the PPS resin composition was calculated by measuring the fiber lengths of 500 or more glass fibers dispersed on the surface of the petri dish using a stereomicroscope and taking an average.

[Production of PPS Resin Composition] (Examples 1 to 3, Comparative Examples 1 and 2)
PPS obtained in Reference Examples 1 to 6 using a twin-screw extruder (TEM-26 manufactured by Toshiba Machine Co., Ltd.) having an intermediate addition port with a diameter of 26 mm, in which the cylinder temperature is set to 320 ° C. and the screw rotation speed is set to 400 rpm. 100 parts by weight of the resin (A) is added from the raw material supply port at the weight ratio shown in Table 1 to make it in a molten state, and (B) the inorganic filler is supplied from the intermediate addition port at the weight ratio shown in Table 1 and the discharge amount is 30 kg. Pellets were obtained by melt-kneading at / hour. Each of the above characteristics was evaluated using this pellet. The results are shown in Table 1.

The PPS resin composition thus obtained has unknown properties of high mechanical strength and excellent dimensional accuracy, weld strength, and cold and thermal impact resistance in a well-balanced manner, and is therefore useful for all automobile parts, and in particular, a plurality of parts. It is usefully used for small, complicated, and thin-walled insert metal-encapsulated molded products that combine the above.

1. 1. Molded product for dimensional accuracy evaluation 2. Gate 3. Insert metal 4. Gate 5. Metal insert molded product

Claims (5)

A polyphenylene sulfide resin composition comprising (A) 100 parts by weight of polyphenylene sulfide resin, (B) 60 to 100 parts by weight of glass fiber, and (C) 80 to 120 parts by weight of calcium carbonate. The (B) glass fiber is a mixture of (B-1) 30 to 50 parts by weight of glass fiber and (B-2) 30 to 50 parts by weight of milled glass fiber, and (B) the number average fiber length of the glass fiber is A polyphenylene sulfide resin composition having a size of 100 to 200 μm. The polyphenylene sulfide resin composition according to claim 1, wherein the fiber diameter of the glass fiber (B) is 9.0 to 14.0 μm. The polyphenylene sulfide resin composition according to claim 1 or 2, wherein the weight ratio of the blended amount of the (B) glass fiber and the (C) calcium carbonate is 1: 1 to 1: 1.25. A molded product comprising the polyphenylene sulfide resin composition according to any one of claims 1 to 3. The molded product according to claim 4, wherein the molded product is a molded product including a metal insert.