JP2023163928A - Injection molding method, manufacturing method of molding, and manufacturing method of metal resin composite - Google Patents

Abstract

To provide an injection molding method for a resin composition containing a PAS resin and a thermoplastic elastomer, the method capable of reducing molding defects and the frequency of mold maintenance.SOLUTION: An injection molding method using an injection unit 100 provided with: a cylinder 2; a screw 3 arranged in the cylinder 2 and capable of compressing and melting, measuring, and injecting a resin supplied from a root portion; and a vent port 20 arranged midway in a longitudinal direction of the cylinder 3 comprises: a supplying step for supplying a resin composition containing a PAS resin and a thermoplastic elastomer to the cylinder 2 of the injection unit 100; a plasticizing step for keeping the cylinder 2 at 290°C or more to plasticize the resin composition in the cylinder 2; an injection step for injecting the resin composition from the cylinder 2 with the screw 3; an exhausting step for exhausting a component vaporized from the resin composition in the plasticizing step or the injection step from the vent port 20; and a molding step for molding the resin composition injected in the injection step using a mold 9.SELECTED DRAWING: Figure 1

Description

The present invention relates to an injection molding method, a method for manufacturing a molded article, and a method for manufacturing a metal-resin composite.

Engineering plastics have excellent productivity, moldability, etc., and are also lightweight, so they are widely used as materials for electrical and electronic equipment, automobiles, etc. as materials that can replace metal materials. Among engineering plastics, polyarylene sulfide resins (hereinafter sometimes referred to as PAS resins), such as polyphenylene sulfide resins (hereinafter sometimes referred to as PPS resins), have excellent mechanical strength, heat resistance, It is known for its excellent chemical properties, moldability, dimensional stability, and flame retardancy. For this reason, PAS resin is increasingly being used in electrical and electronic equipment parts and automobile parts. As described above, as the adoption of PAS resin is progressing, demands for quality and processability of PAS resin are increasing year by year. For example, PAS resin has a high melting point and processing temperature is high, so low molecular weight components derived from PAS resin and low boiling point compounds derived from olefin polymers that are blended to improve the performance of PAS resin are injection molded. Sometimes these components volatilize, and these volatilized components may cause molding defects that impair the appearance and performance of the resulting molded product. Furthermore, these volatilized components may cause mold stains, which may increase the frequency of maintenance. Further, these volatilized components may clog the gas vent, causing molding defects.

Patent Document 1 describes a metal/resin composite structure obtained by joining a metal member and a molded product of a polyarylene sulfide resin composition (hereinafter sometimes referred to as a resin composition), and a method for manufacturing the same. has been done. Patent Document 1 describes that PAS resin is represented by PPS resin, exhibits excellent heat resistance capable of maintaining a melting point of 270°C or higher, and has excellent mechanical strength, chemical resistance, moldability, and dimensions. It is described that it has excellent stability. Furthermore, Patent Document 1 describes a PAS resin in which additives such as fillers and elastomers are blended with the PAS resin, and these are melt-kneaded to be dispersed in a matrix made of the PAS resin to form a resin composition. It is described that it can be melt-molded and processed into various molded products such as electric/electronic equipment parts, automobile parts, etc.

Patent Document 2 describes a vent-type injection molding device and an injection molding method using the injection molding device. The vented injection molding apparatus includes a cylinder, a screw, a screw drive device, a raw material supply device, a heating device, and a control device. A vent port is provided in the middle of the cylinder in the longitudinal direction to communicate the inside of the cylinder with the outside. The raw material supplied from the raw material supply device melts inside the cylinder before reaching the vent port, and unnecessary gases and the like are discharged from the vent port. As an example of the raw material, an alloy resin containing polycarbonate and ABS resin is exemplified.

Patent Document 3 describes a thermoplastic resin molded product and a method for manufacturing the thermoplastic resin molded product. Examples of the thermoplastic resin include polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyamide, polyacetal, polyphenylene ether, or compositions thereof. In the method for manufacturing a thermoplastic resin molded article described in Patent Document 3, a resin mixture that is a raw material for a thermoplastic resin molded article is directly molded using an injection molding machine without going through an extrusion melt-kneading process. In a method for manufacturing a thermoplastic resin molded article, a vent-type injection molding machine is used as an injection molding machine. Patent Document 3 states that the resin mixture that is the raw material for thermoplastic resin molded products contains water and various low molecular weight substances, and when molded using a normal injection molding machine, decomposition and foaming occur, resulting in poor appearance and It is described that a vent-type injection molding machine is used to remove moisture and low molecular weight substances since this is disadvantageous as it causes a decrease in mechanical strength.

JP 2019-10816 Publication JP2017-81088A Japanese Patent Application Publication No. 6-32912

As mentioned above, PAS resin has excellent mechanical strength, heat resistance, chemical resistance, moldability, dimensional stability, and flame retardancy, but the processing temperature is high and the low molecular weight derived from PAS resin during injection molding. The components and low boiling point compounds blended to improve the performance of the PAS resin volatilize, and these volatilized components may cause molding defects in molded products and an increase in the frequency of mold maintenance. Therefore, an injection molding method for a resin composition, a method for manufacturing a molded article, and a metal resin that can reduce molding defects of a molded article of a resin composition containing a PAS resin and the frequency of maintenance of a mold for molding this resin composition. It would be desirable to provide a method for producing a composite.

The present invention has been made in view of the above circumstances, and its purpose is to reduce molding defects and mold maintenance frequency in an injection molding method for a resin composition containing a PAS resin and a thermoplastic elastomer. It is an object of the present invention to provide an injection molding method, a method for manufacturing a molded article, and a method for manufacturing a metal-resin composite, which can be used.

The injection molding method according to the present invention for achieving the above object includes:
A cylinder having a nozzle at its tip and capable of heating control divided into at least two blocks in the longitudinal direction; a screw placed within the cylinder and capable of compressing and melting, metering and injecting resin supplied from the base; and the cylinder. In an injection molding method using an injection unit equipped with a vent port disposed in the middle of the longitudinal direction,
a supplying step of supplying a resin composition containing a PAS resin and a thermoplastic elastomer to the cylinder of the injection unit;
a plasticizing step of plasticizing the resin composition in the cylinder by maintaining the cylinder at 290° C. or higher;
a discharge step of discharging the components volatilized from the resin composition in the plasticizing step from the vent port;
an injection step of injecting the resin composition from the cylinder with the screw;
The method includes a molding step of molding the resin composition injected in the injection step using a mold.

A method for manufacturing a molded article according to the present invention for achieving the above object is a method for manufacturing a molded article of the above-mentioned resin composition using the above-mentioned injection molding method.

A method for manufacturing a metal-resin composite according to the present invention for achieving the above object is a method for manufacturing a metal-resin composite of the above-mentioned resin composition and a metal member using the above-mentioned injection molding method, comprising:
The method includes a step of arranging the metal member within the mold.

An injection molding method for a resin composition containing a PAS resin and a thermoplastic elastomer, which can reduce molding defects and the frequency of maintenance of a mold, a method for producing a molded article of the resin composition, and a metal-resin composite Provides a manufacturing method.

1 is a diagram showing the basic configuration of an injection molding apparatus that implements an injection molding method according to the present embodiment. It is a figure showing an example of a mold. FIG. 3 is a schematic diagram of a second test piece.

An injection molding method according to an embodiment of the present invention will be described with reference to the drawings.

(Explanation of overview)
FIG. 1 shows an injection unit 100 and a mold 9 connected to the downstream side of the injection unit 100 as an example of an injection molding apparatus that implements the injection molding method according to the present embodiment.

The injection unit 100 includes a cylinder 2 which has a nozzle 22 at its tip and which can be divided into at least two blocks in the longitudinal direction and which can be heated and controlled, and a cylinder 2 which is arranged in the cylinder 2 and which compresses, melts, meters and injects the resin supplied from the base. The cylinder 2 is provided with a screw 3 that can be opened, and a vent port 20 disposed midway in the longitudinal direction of the cylinder 2.

The injection molding method according to the present embodiment includes a supply step of supplying a resin composition containing a PAS resin and a thermoplastic elastomer to a cylinder 2 of an injection unit 100, and a step of supplying a resin composition containing a PAS resin and a thermoplastic elastomer to a cylinder 2 while maintaining the cylinder 2 at a temperature of 290°C or higher. a plasticizing step in which the resin composition is plasticized, a discharge step in which the components volatilized from the resin composition in the plasticizing step are discharged from the vent port 20, and an injection step in which the resin composition is injected from the cylinder 2 with the screw 3. , a molding step of molding the resin composition injected in the injection step using a mold 9.

According to the injection molding method according to the present embodiment, molding defects and the frequency of maintenance of the mold 9 can be reduced in the injection molding method of a resin composition containing a PAS resin and a thermoplastic elastomer.

(Detailed explanation)
Below, each component constituting the resin composition according to the present embodiment will be explained, and subsequently, the injection molding method according to the present embodiment will be explained.

<Resin composition>
The resin composition according to this embodiment includes a PAS resin and a thermoplastic elastomer. The resin composition may further contain an inorganic filler, a mold release agent, or other components.

(Polyarylene sulfide resin)
The resin composition according to this embodiment includes a PAS resin. PAS resin has a resin structure in which the repeating unit is a structure in which an aromatic ring and a sulfur atom are bonded. Specifically, the PAS resin has a structural part represented by the following general formula (1) and Furthermore, it is a resin having a trifunctional structural moiety represented by the following general formula (2) as a repeating unit.

In addition, in formula (1), R ¹ and R ² each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a nitro group, an amino group, a phenyl group, a methoxy group, or an ethoxy group. .

The trifunctional structural moiety represented by the above general formula (2) preferably ranges from 0.001 to 3 mol%, particularly from 0.01 to 1 mol%, based on the total number of moles with other structural moieties. The preferred range is mole %.

Here, the structural moiety represented by the above general formula (1), especially R ¹ and R ² in formula (1), is preferably a hydrogen atom from the viewpoint of mechanical strength of the PAS resin, and in that case, , those bonded at the para position represented by the following formula (3), and those bonded at the meta position represented by the following formula (4).

Among these, it is particularly preferable that the sulfur atom is bonded to the aromatic ring in the repeating unit in a structure in which it is bonded at the para position represented by the above general formula (3) from the viewpoint of heat-and-moisture resistance and crystallinity of the PAS resin. .

In addition, PAS resin has not only the structural parts represented by general formulas (1) and (2), but also the structural parts represented by the following structural formulas (5) to (8) as shown in general formula (1). It may be contained in an amount of 30 mol% or less of the total amount with the structural moiety represented by general formula (2).

Further, it is preferable that the content of the structural moieties represented by the above general formulas (5) to (8) is 10 mol % or less from the viewpoint of heat-and-moisture resistance and mechanical strength of the PAS resin. When the PAS resin contains structural moieties represented by the above general formulas (5) to (8), their bonding mode may be either a random copolymer or a block copolymer.

Furthermore, the PAS resin may have a naphthyl sulfide bond or the like in its molecular structure, but it is preferably 3 mol% or less, particularly 1 mol% or less, based on the total number of moles with other structural parts. It is preferable that

Further, the physical properties of the PAS resin are not particularly limited as long as they do not impair the effects of this embodiment, but are as follows.

(melt viscosity)
The melt viscosity of the PAS resin used in the present invention is not particularly limited, but the melt viscosity (V6) measured at 300°C is preferably in the range of 2 Pa·s or more because it provides a good balance between fluidity and mechanical strength. It is preferably in the range of 1000 Pa·s or less, more preferably in the range of 500 Pa·s or less, still more preferably in the range of 200 Pa·s or less. The most suitable range of melt viscosity (V6) measured at 300° C. is 5 Pa·s or more and 100 Pa·s or less. When the melt viscosity becomes high, gas is generated due to shear heat generation within the mold, and the gas generated within the mold may cause molding defects. However, the melt viscosity (V6) of the PAS resin was measured using a Shimadzu flow tester, CFT-500D, at 300°C, load: 1.96 x 10 ⁶ Pa, L/D = 10 (mm)/ This is the measured value of melt viscosity measured after holding at 1 (mm) for 6 minutes.

(non-Newtonian index)
The non-Newtonian index of the PAS resin used in the present invention is not particularly limited, but is preferably in the range of 0.90 or more and 2.00 or less. When using a linear PAS resin, the non-Newtonian index is preferably in the range of 0.90 or more, more preferably in the range of 0.95 or more, and preferably in the range of 1.50 or less, more preferably 1.20. The range is as follows. Such PAS resins have excellent mechanical properties, fluidity, and abrasion resistance. However, in the present invention, the non-Newtonian exponent (N value) is determined using a capillograph under the conditions of melting point +20°C, ratio of orifice length (L) to orifice diameter (D), and shear rate (SR) of 40. ) and shear stress (SS) were measured and calculated using the following formula. The closer the non-Newtonian index (N value) is to 1, the more linear the structure is, and the higher the non-Newtonian index (N value) is, the more branched the structure is. In the formula below, SR is shear rate (sec ^-1 ), SS is shear stress (dynes/cm ² ), and K is a constant.

The method for producing PAS resin is not particularly limited, but for example (Production method 1) a dihalogeno aromatic compound is polymerized in the presence of sulfur and sodium carbonate, and if necessary, a polyhalogeno aromatic compound or other copolymerization component is added. (Manufacturing method 2) A method of polymerizing a dihalogeno aromatic compound in the presence of a sulfidating agent, etc. in a polar solvent, adding a polyhalogeno aromatic compound or other copolymerization components if necessary, (Manufacturing method 3) A method in which p-chlorothiophenol is self-condensed by adding other copolymerization components if necessary, (Production method 4) A method in which a diiodo aromatic compound and an elemental sulfur are combined with a functional group such as a carboxy group or an amino group. Examples include a method of performing melt polymerization under reduced pressure in the presence of a polymerization inhibitor that may be included.

Among these manufacturing methods, the method (manufacturing method 2) is preferred because it is versatile. During the reaction, an alkali metal salt of carboxylic acid or sulfonic acid, or an alkali hydroxide may be added to adjust the degree of polymerization.

In addition, in the method (Production method 2), a hydrous sulfidating agent is introduced into a heated mixture containing an organic polar solvent and a dihalogeno aromatic compound at a rate that allows water to be removed from the reaction mixture, and the dihalogeno aromatic compound is introduced in the organic polar solvent. The aromatic compound and the sulfidating agent are added and reacted with the polyhalogeno aromatic compound as needed, and the amount of water in the reaction system is adjusted to 0.02 to 0.5 mol per mol of the organic polar solvent. A method for producing PAS resin by controlling the range (see Japanese Patent Application Laid-Open No. 07-228699), or a method for producing PAS resin by controlling the amount within a range of A polyhalogeno aromatic compound or other copolymerization components are added, and an alkali metal hydrosulfide and an alkali metal salt of an organic acid are added in an amount of 0.01 to 0.9 mol per mol of the sulfur source. Particularly preferred are those obtained by a method in which the reaction is carried out while controlling the amount of water in the reaction system within a range of 0.02 mol or less per 1 mol of the aprotic polar organic solvent (see WO2010/058713 pamphlet).

Specific examples of dihalogeno aromatic compounds include p-dihalobenzene, m-dihalobenzene, o-dihalobenzene, 2,5-dihalotoluene, 1,4-dihalonaphthalene, 1-methoxy-2,5-dihalobenzene, 4, 4'-dihalobiphenyl, 3,5-dihalobenzoic acid, 2,4-dihalobenzoic acid, 2,5-dihalonitrobenzene, 2,4-dihalonitrobenzene, 2,4-dihaloanisole, p,p '-Dihalodiphenyl ether, 4,4'-dihalobenzophenone, 4,4'-dihalodiphenylsulfone, 4,4'-dihalodiphenylsulfoxide, 4,4'-dihalodiphenylsulfide, and each of the above compounds Examples of polyhalogeno aromatic compounds include 1,2,3-trihalobenzene, 1,2,4-trihalobenzene, 1,3, Examples include 5-trihalobenzene, 1,2,3,5-tetrahalobenzene, 1,2,4,5-tetrahalobenzene, and 1,4,6-trihalonaphthalene. Note that the halogen atom contained in each of the above compounds is preferably a chlorine atom or a bromine atom.

Furthermore, there are no particular limitations on the method for post-treatment of the reaction mixture containing the PAS resin obtained in the polymerization step. For example, (post-treatment 1) after the polymerization reaction is completed, firstly, the reaction mixture is used as it is, or after adding an acid or a base, the solvent is distilled off under reduced pressure or normal pressure, and then the solid after the solvent distillation is washed with water. , washed once or twice or more with a reaction solvent (or an organic solvent with equivalent solubility for the low-molecular polymer), acetone, methyl ethyl ketone, alcohol, etc., and then neutralized, washed with water, filtered, and dried. Method: (Post-treatment 2) After the polymerization reaction is completed, add a solvent such as water, acetone, methyl ethyl ketone, alcohols, ethers, halogenated hydrocarbons, aromatic hydrocarbons, aliphatic hydrocarbons (the polymerization solvent used) to the reaction mixture. A solvent that is soluble in PAS and is at least a poor solvent for PAS is added as a precipitant to precipitate solid products such as PAS and inorganic salts, which are then filtered, washed, and dried. Method: (Post-treatment 3) After the polymerization reaction is completed, a reaction solvent (or an organic solvent having an equivalent solubility for the low-molecular-weight polymer) is added to the reaction mixture, stirred, and then filtered to remove the low-molecular-weight polymer. After that, the polymer is washed once or twice or more with a solvent such as water, acetone, methyl ethyl ketone, alcohol, etc., and then neutralized, washed with water, filtered, and dried; (Post-treatment 4) After the polymerization reaction is completed, the reaction mixture is A method of adding water, washing with water, filtration, adding an acid at the time of washing with water as necessary, acid treatment, and drying; or; (Post-treatment 5) After the completion of the polymerization reaction, the reaction mixture is filtered, and the reaction mixture is filtered as necessary. Depending on the situation, examples include washing with a reaction solvent once or twice or more, followed by washing with water, filtration, and drying.

In addition, in the post-treatment methods exemplified in (Post-treatment 1) to (Post-treatment 5) above, the PAS resin may be dried in vacuum, in air or in an inert gas atmosphere such as nitrogen. You can also do it with

(thermoplastic elastomer)
The resin composition according to this embodiment contains a thermoplastic elastomer as an essential component. Examples of the thermoplastic elastomer include polyolefin elastomers, fluorine elastomers, and silicone elastomers, and among these, polyolefin elastomers are preferred. When adding these elastomers, the blending amount is not particularly limited as long as it does not impair the effects of the present invention, but it is preferably 0.5 parts by mass or more, more preferably 1.0 parts by mass, based on 100 parts by mass of the PAS resin. The amount ranges from at least 20 parts by mass, preferably at most 20 parts by mass, and more preferably at most 15 parts by mass. This range is preferable because the impact resistance of the resulting PAS resin composition is improved.

(Release agent)
The resin composition according to the present embodiment may contain a mold release agent in order to improve mold release properties from a mold during injection molding. Examples of the mold release agent include known ones such as metal salts and esters of fatty acids having 18 to 30 carbon atoms, including stearic acid and montanic acid, and polyolefin waxes such as polyethylene. In the present invention, the term "mold release agent" refers to a low molecular weight resin that is normally solid at 25° C. and exhibits a mold release effect, for example, within a mold during melt molding as an additive to the PAS resin composition.

The mold release agent in the resin composition is an optional component, but when blending these mold release agents, the ratio of the blend is not particularly limited as long as it does not impair the effects of this embodiment, but it is not limited to 100 parts by mass of PAS resin. , preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, preferably 5 parts by mass or less, more preferably 4.5 parts by mass or less. , more preferably 4 parts by mass or less. Within the above range, the molded product has excellent mold releasability from the mold. Furthermore, it is possible to suppress staining of the mold during molding and deterioration of the appearance of the molded product, thereby reducing molding defects and the frequency of maintenance of the mold.

(filler)
The resin composition according to the present embodiment may contain an organic or inorganic filler as an optional component, if necessary. As these fillers, known and commonly used materials can be used as long as they do not impair the effects of this embodiment. fillers, etc. Specifically, fibrous fillers such as glass fiber, carbon fiber, silane glass fiber, ceramic fiber, aramid fiber, metal fiber, potassium titanate, silicon carbide, calcium silicate, wollastonite, natural fiber, etc. Can also be used for glass beads, glass flakes, barium sulfate, clay, pyrophyllite, bentonite, sericite, mica, mica, talc, attapulgite, ferrite, calcium silicate, calcium carbonate, glass beads, zeolite, milled fiber, calcium sulfate Non-fibrous fillers can also be used.

In this embodiment, the filler is not an essential component, and when blended, its content is not particularly limited as long as it does not impair the effects of this embodiment. The blending amount of the filler is, for example, preferably 1 part by mass or more, more preferably 10 parts by mass or more, preferably 600 parts by mass or less, more preferably 200 parts by mass or less, per 100 parts by mass of the PAS resin. range. This range is preferable because the resin composition exhibits good mechanical strength and moldability.

When the filler is an inorganic filler such as glass fiber or glass flakes, the resin composition preferably contains 50 parts by mass or more and 150 parts by mass or less of the inorganic filler based on 100 parts by mass of the PAS resin. As a result, in the injection molding method according to the present embodiment, when the resin composition contains an inorganic filler, the resin composition exhibits better mechanical strength and moldability, and reduces molding defects and mold maintenance frequency. can be reduced.

(Silane coupling agent)
The resin composition according to the present embodiment may contain a silane coupling agent as an optional component, if necessary. The silane coupling agent is not particularly limited as long as it does not impair the effects of this embodiment, but silane coupling agents having a functional group that reacts with a carboxy group, such as an epoxy group, an isocyanato group, an amino group, or a hydroxyl group, are preferred. It is mentioned as. Examples of such silane coupling agents include epoxy groups such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. Containing alkoxysilane compounds, γ-isocyanatopropyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropylmethyldimethoxysilane, γ-isocyanatopropylmethyldiethoxysilane, γ-isocyanatopropylethyldimethoxysilane , γ-isocyanatopropylethyldiethoxysilane, γ-isocyanatopropyltrichlorosilane and other isocyanato group-containing alkoxysilane compounds, γ-(2-aminoethyl)aminopropylmethyldimethoxysilane, γ-(2-aminoethyl)amino Examples include amino group-containing alkoxysilane compounds such as propyltrimethoxysilane and γ-aminopropyltrimethoxysilane, and hydroxyl group-containing alkoxysilane compounds such as γ-hydroxypropyltrimethoxysilane and γ-hydroxypropyltriethoxysilane. In this embodiment, the silane coupling agent is not an essential component, but if it is blended, the amount added is not particularly limited as long as it does not impair the effects of this embodiment, but it can be added to 100 parts by mass of PAS resin. , preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, preferably 10 parts by mass or less, more preferably 5 parts by mass or less. This range is preferable because the resin composition has good corona resistance and moldability, especially mold releasability, and the molded product exhibits excellent adhesion to the epoxy resin while further improving mechanical strength.

(Other resin components)
Furthermore, in addition to the above-mentioned components, the resin composition according to the present embodiment may further contain polyester resin, polyamide resin, polyimide resin, polyetherimide resin, polycarbonate resin, polyphenylene ether resin, polysulfone resin, as appropriate depending on the application. , polyether sulfone resin, polyether ether ketone resin, polyether ketone resin, polyarylene resin, polyethylene resin, polypropylene resin, polytetrafluoroethylene resin, polydifluoroethylene resin, polystyrene resin, ABS resin, phenol resin, Synthetic resins (hereinafter simply referred to as synthetic resins) such as urethane resins and liquid crystal polymers can be blended as optional components. In this embodiment, the above-mentioned synthetic resin is not an essential component, but if it is blended, the proportion of the blend is not particularly limited as long as it does not impair the effects of this embodiment, and may vary depending on the purpose. Although it cannot be unconditionally defined, the proportion of the synthetic resin blended into the resin composition according to the present embodiment is, for example, in the range of 5 parts by mass or more and 15 parts by mass or less with respect to 100 parts by mass of the PAS resin. Examples include degrees of range. In other words, the ratio of PAS resin to the total of PAS resin and synthetic resin is preferably in the range of (100/115) or more, and more preferably in the range of (100/105) or more, based on mass. .

(Other additives)
In addition, the resin composition according to the present embodiment can also be used as a colorant, an antistatic agent, an antioxidant, a heat stabilizer, an ultraviolet stabilizer, an ultraviolet absorber, a foaming agent, a flame retardant, a flame retardant aid, and a rust preventive agent. Known and commonly used additives such as agents and coupling agents may be included as optional components, if necessary. These additives are not essential components, and for example, preferably in an amount of 0.01 parts by mass or more, and preferably in a range of 1000 parts by mass or less, per 100 parts by mass of the PAS resin, they can achieve the effects of this embodiment. It may be used by adjusting it as appropriate depending on the purpose and use so as not to damage it.

<Method for manufacturing resin composition>
The method for producing a resin composition according to the present embodiment includes a step of blending a PAS resin and a thermoplastic elastomer as essential components, and melting and kneading the mixture at a temperature range equal to or higher than the melting point of the PAS resin.

The resin composition according to the present embodiment is formed by blending each essential component and other optional components as necessary. Methods for producing the resin composition used in the present invention include, but are not particularly limited to, a method of blending essential components and optional components as necessary, and melting and kneading, more specifically, using a tumbler or Henschel as necessary. Examples include a method of uniformly dry mixing using a mixer or the like, and then charging the mixture into a twin-screw extruder and melt-kneading it.

The melt kneading is carried out in a temperature range in which the resin temperature is equal to or higher than the melting point of the PAS resin, preferably in a temperature range in which the melting point is equal to or higher than the melting point +10 °C, more preferably at the melting point +10 °C or higher, still more preferably at the melting point +20 °C or higher, preferably at the melting point +100 °C or higher. It can be carried out by heating to a temperature in the range of 0.degree. C. or lower, more preferably 50.degree. C. or lower than the melting point.

As the melt-kneading machine, a twin-screw kneading extruder is preferable from the viewpoint of dispersibility and productivity. It is preferable to melt and knead while adjusting the range as appropriate, and it is preferable to melt and knead under conditions such that the ratio (discharge amount/screw rotation speed) is in the range of 0.02 to 5 (kg/hr/rpm). More preferred. Further, the addition and mixing of each component to the melt-kneading machine may be performed simultaneously or may be performed separately. For example, when adding additives, it is preferable to introduce them into the extruder from the side feeder of a twin-screw kneading extruder from the viewpoint of dispersibility. The position of the side feeder is such that the ratio of the distance from the extruder resin input part (top feeder) to the side feeder to the total screw length of the twin-screw kneading extruder is preferably 0.1 or more, and preferably 0.3 or more. It is more preferable that Moreover, it is preferable that this ratio is 0.9 or less, and it is more preferable that it is 0.7 or less.

The resin composition according to the present invention obtained by melt-kneading in this way is a molten mixture containing essential components, optional components added as necessary, and components derived from these components, and after melt-kneading, the resin composition is prepared by a known method, For example, a molten resin composition is extruded into a strand shape, processed into pellets, chips, granules, powder, etc., and then pre-dried at a temperature of 100°C or more and 150°C or less, if necessary. You may.

The resin composition according to the present embodiment can be used for various molding processes such as injection molding, compression molding, extrusion molding such as composites, sheets, and pipes, pultrusion molding, blow molding, and transfer molding. It is also suitable for injection molding applications, which will be described later.

<Injection molding method>
FIG. 1 shows an example of an injection unit 100 and a mold 9 that constitute an injection molding apparatus that implements the injection molding method according to the present embodiment.

As shown in FIG. 1, the injection unit 100 includes a cylinder 2 that conveys the resin composition to be injected, a screw 3 disposed inside the cylinder 2 that melts, measures, and injects the resin composition, and a raw material in the cylinder 2. a nozzle 22 that supplies the resin from the cylinder 2 to the mold 9; a heating device 4 that heats the cylinder 2; The control unit C controls the entire operation of the injection unit 100, such as the temperature of the injection unit 100.

In the injection unit 100 , the resin composition supplied from the supply mechanism 1 is plasticized inside the cylinder 2 , and the resin composition is injected from the base end of the cylinder 2 to the distal end side using the screw 3 and is injected from the nozzle 22 . It is poured into a mold 9.

The control unit C is a functional unit realized by a CPU, a control device such as a sequencer or a personal computer having a built-in CPU, or the above-mentioned CPU by executing software. The control unit C controls the operation of the injection unit 100 based on a predetermined program or operation command. In the following description, a case will be described in which the operation of each part of the injection unit 100 is controlled by the control section C, unless otherwise specified.

The cylinder 2 is a cylindrical member in which a space is formed along its longitudinal direction to allow the resin composition to flow therethrough. The cylinder 2 is made of metal such as an iron alloy. For example, a metal screw 3 is inserted into the cylinder 2 . A supply mechanism 1 is connected to a side portion of the cylinder 2 on the base end side. A nozzle 22 is connected to the tip of the cylinder 2. A plurality of heating devices 4 such as electric heaters are attached to the body of the cylinder 2 at predetermined intervals in the longitudinal direction, and heating can be controlled by dividing into at least two blocks (parts) in the longitudinal direction. It looks like this. In this embodiment, the cylinder 2 can be heated and controlled in two blocks: a block upstream from the vent port and a block downstream from the vent port. An opening communicating with the inside of the cylinder 2 is formed in the body of the cylinder 2 as a vent port 20 .

The temperature of the cylinder 2 can be maintained at a predetermined temperature by heating with the heating device 4. The temperature of each part of the cylinder 2 may be arbitrarily adjustable by adjusting the output of the heating device 4 at each part in the longitudinal direction of the cylinder 2.

At least a portion of the cylinder 2 has a temperature range above the melting point of the PAS resin, preferably a temperature range above the melting point +10°C, more preferably a temperature range from above the melting point +10°C to below the melting point +100°C, even more preferably above the melting point +20°C. to melting point +50°C or less. In this embodiment, at least a portion of the cylinder 2 is maintained at 290° C. or higher. By maintaining the cylinder 2 at such a temperature, the resin composition can be heated to this temperature range and plasticized.

The temperature upstream of the vent port 20 in the cylinder 2 is preferably in a temperature range equal to or higher than the melting point of the PAS resin, preferably in a temperature range equal to or higher than the melting point +10 °C, more preferably in a temperature range from the melting point +10 °C or higher to the melting point +100 °C or lower, More preferably, the temperature is maintained within the range of melting point +20°C or higher to melting point +50°C or lower. Thereby, the resin composition can be plasticized on the upstream side of the vent port 20. In addition, plasticization of the resin composition is a state in which the temperature of the resin composition reaches a temperature range equal to or higher than the melting point of the PAS resin, and the resin composition supplied in the form of solid powder or granules undergoes a phase transition to a viscous liquid state. say something

The vent port 20 removes components volatilized within the cylinder 2, such as water contained in the resin composition, low molecular weight components derived from PAS resin, and low boiling point compounds derived from olefin polymers blended to improve the performance of PAS resin. , etc., can be discharged from the cylinder 2 to the outside of the cylinder 2 (outside the system) through the vent port 20. Thereby, as will be described later, it is possible to reduce molding defects of the molded body 5 and the frequency of maintenance of the mold 9. That is, molding defects that impair the appearance and performance of the molded body 5 can be reduced. Further, staining of the mold 9 due to these volatilized components can be suppressed, and the frequency of maintenance of the mold 9 can be reduced. In addition, it is possible to suppress clogging of the gas vent slit 97 (see FIG. 2) of the mold 9 due to these volatilized components, thereby reducing molding defects.

The vent port 20 is preferably arranged downstream of the region where the resin composition is plasticized (the region where the resin composition is melted) in the cylinder 2 . That is, the vent port 20 is preferably provided in the cylinder 2 at a position where the above-described discharge step is performed after the resin composition is plasticized. Thereby, the components volatilized when the resin composition is plasticized can be appropriately discharged from the vent port 20, and the molding defects of the molded body 5 and the maintenance frequency of the mold 9 can be appropriately reduced.

The vent port 20 may be opened to the atmosphere to discharge components that have evaporated from the resin composition when the resin composition is plasticized, but it is also possible to use a suction device such as a fan or blower to suck and discharge the components that have evaporated from the resin composition. It's okay. Thereby, the components volatilized when the resin composition is plasticized can be reliably discharged from the vent port 20, and it may be possible to further reduce molding defects of the molded body 5 and maintenance frequency of the mold 9.

In the injection unit 100, for example, the temperature of the portion of the cylinder 2 on the downstream side of the vent port 20 can be maintained lower than the temperature of the portion of the cylinder 2 on the upstream side of the vent port 20. For example, the temperature of the portion of the cylinder 2 on the downstream side can be maintained lower than the temperature of the portion of the cylinder 2 upstream of the vent port 20 by 10° C. or more and 60° C. or less. Thereby, it may be possible to reduce gas generation from the resin composition after plasticization and to perform stable injection of the resin composition.

The screw 3 may be, for example, a rod-shaped main body in which a typical flight is spirally formed, and which has a supply section, a compression section, and a metering section with different pitches and groove depths. . In the injection unit 100, the screw 3 is rotated by a drive unit such as an electric motor, thereby transporting the resin composition in the cylinder 2 from the proximal end to the distal end of the cylinder 2, while plasticizing and melting the resin composition in the compression unit. The resin composition can be measured and injected into the mold 9 through the nozzle 22 .

In the screw 3, the root side 31, which is the part upstream of the vent port 20 in the longitudinal direction of the screw 3, is the supply part and the compression part, and the tip side, which is the part downstream of the vent port 20. 32 is a measuring section. In other words, the vent port 20 is installed between the upstream part of the cylinder 2 that accommodates the root side 31 of the screw 3 and the downstream part of the cylinder 2 that accommodates the tip side 32 of the screw 3. In the screw 3, the pitch of the screw becomes narrower from the middle part of the root side 31 to the tip side 32 in the longitudinal direction than the root side, and the groove of the screw gradually becomes shallower.

The supply mechanism 1 is a mechanism for supplying the resin composition to the cylinder 2. In FIG. 1, as an example of the supply mechanism 1, a hopper equipped with a supply speed control mechanism 10 such as an opening adjustment valve is connected to the base end side of the cylinder 2. A hopper serving as the supply mechanism 1 is capable of supplying the resin composition into the cylinder 2 through an opening communicating with the space inside the cylinder on the base end side of the cylinder 2 . The supply mechanism 1 is not limited to this example, and may include a quantitative supply machine such as a screw feeder or a vibration feeder. Further, the supply speed control mechanism 10 may be provided with a valve body such as a rotary valve instead of the opening adjustment valve.

In this embodiment, the supply mechanism 1 can adjust the supply rate of the resin composition to the cylinder 2 so that the cylinder 2 is in a starvation state. By bringing the cylinder 2 into a starvation state and maintaining the cylinder 2 in a starvation state, vent-up can be avoided and discharge of components volatilized within the cylinder 2 can be promoted. By maintaining the cylinder 2 in a starvation state, components volatilized within the cylinder 2 are easily discharged from the vent port 20 and the opening of the cylinder 2 to which the hopper as the supply mechanism 1 is connected. Note that the starvation state in this embodiment indicates that the amount of resin composition conveyed by the screw 3 in the cylinder 2 is less than the material conveyance capacity of the screw 3. That is, it shows that the cylinder 2 is not saturated with the resin composition supplied by its own weight from the hopper.

The resin composition injected from the injection unit 100 is molded in a mold 9. The mold 9 includes, for example, a first mold 91 and a second mold 92, and the resin composition injected from the injection unit 100 into the space formed between the first mold 91 and the second mold 92. Objects can be supplied through the gate 90. Thereby, a molded body 5 having a shape corresponding to the space (hereinafter sometimes referred to as a cavity) formed between the first mold 91 and the second mold 92 can be obtained. When the mold 9 is supplied with the resin composition injected from the cylinder 2 by a heating device (for example, a heating device of a mold clamping device that clamps the mold 9) (not shown), the temperature is, for example, 120° C. or higher and 200° C. It is maintained at a temperature of 130°C or higher and 180°C or lower, preferably 130°C or higher and 180°C or lower.

FIG. 2 shows an example of a mold 9 suitable for evaluation of injection molding methods. The mold 9 shown in FIG. 2 has, for example, slit pieces 95 and 96 that form a slit-like gas vent slit 97 that communicates the cavity with the outside. The gas vent slit 97 is a gap formed between the slit pieces 95 and 96 that are in contact with each other. The gas vent slit 97 functions as a gas flow path for discharging gas in the cavity to the outside by communicating the cavity with the outside. In addition, in FIG. 2, the case where the metal mold|die 9 is for molding the cup-shaped molded object 51 is illustrated.

<Method for manufacturing molded products>
In the method for manufacturing a molded article according to the present embodiment, a molded article of a resin composition is manufactured using the injection molding method described above. That is, the method for manufacturing a molded product according to the present embodiment includes a cylinder that has a nozzle at its tip and can be heated by dividing it into at least two blocks in the longitudinal direction, and a resin that is placed inside the cylinder and is supplied from the base. A molded product of a resin composition containing a PAS resin and a thermoplastic elastomer is produced using an injection unit equipped with a screw capable of compressing, melting, metering, and injecting PAS resin, and a vent port placed halfway in the longitudinal direction of the cylinder. The manufacturing method includes a supply step of supplying a resin composition to a cylinder of an injection unit, a plasticization step of maintaining the cylinder at 290° C. or higher and plasticizing the resin composition in the cylinder, and a step of plasticizing the resin composition in the cylinder. A discharge step for discharging volatile components from the composition from a vent port, an injection step for injecting the resin composition from a cylinder with a screw, and a molding step for molding the resin composition injected in the injection step with a mold. include.

The molded article according to this embodiment has a morphology in which the PAS resin forms a continuous phase and the thermoplastic elastomer and optional components are dispersed. When a PAS resin molded article has such a morphology, a molded article with excellent chemical resistance, heat resistance, and mechanical strength can be obtained.

The application of the molded product according to this embodiment is not particularly limited and can be used as various products, but in particular, the molded product can be used in various products after placing the metal member in the mold and then placing the resin composition in the mold. Because it exhibits stable performance in the molding of metal-resin composites (composite molded products) obtained by insert molding that is injection molded, and parts that are molded by secondary molding on primary resin molded products. It can be preferably used.

<Method for manufacturing metal resin composite>
The method for manufacturing a metal-resin composite according to the present embodiment is a method for manufacturing a metal-resin composite of a resin composition and a metal member using the above-described injection molding method, the metal member being placed in a mold. Including process. In other words, the method for manufacturing a metal-resin composite consists of a cylinder that has a nozzle at its tip and can be divided into at least two blocks in the longitudinal direction and can be heated and controlled; , a resin composition containing a PAS resin and a thermoplastic elastomer, and a metal member, using an injection unit equipped with a screw capable of metering and injection, and a vent port disposed midway in the longitudinal direction of the cylinder. A method for producing a metal-resin composite, comprising: a supply step of supplying a resin composition to a cylinder of an injection unit; a plasticizing step of maintaining the cylinder at 290° C. or higher and plasticizing the resin composition in the cylinder; A discharge process in which components volatilized from the resin composition are discharged from a vent port during the plasticization process, an injection process in which the resin composition is injected from a cylinder with a screw, a placement process in which a metal member is placed in a mold, and an injection process. A molding step of molding the injected resin composition in a mold. Note that the placement step is performed before the resin composition injected from the cylinder is cast into a mold.

The metal member used in this embodiment can be a metal member cut into a predetermined shape and used as it is, but by roughening at least a part of the joint surface with the resin member, a roughened surface can be formed. It is also possible to use a metal member. When a metal member having a roughened surface on at least a portion of the surface is used, the molten resin member can more reliably penetrate deeper into the roughened surface of the metal member, which has an expanded surface area due to surface roughening. As a result, the anchor effect improves the bonding strength between the resin member and the metal member, which is preferable.

Any known metal parts can be used regardless of the type of metal parts used in this embodiment. That is, examples include aluminum, copper, stainless steel, magnesium, iron, titanium, and alloys containing these. More specifically, iron, for example, stainless steel, steel, etc., has iron as the main component, that is, 20% by mass or more, more preferably 50% by mass or more, still more preferably 80% by mass, and carbon, silicon, etc. , alloys containing manganese, chromium, tungsten, molybdenum, phosphorus, titanium, vanadium, nickel, zirconium, boron, etc. (hereinafter referred to as iron alloys), aluminum, and alloys containing aluminum as a main component, as well as copper, manganese, silicon, and magnesium. , alloys containing zinc, nickel (hereinafter referred to as aluminum alloys), magnesium, alloys containing magnesium as a main component and also containing zinc, aluminum, zirconium, etc. (hereinafter referred to as magnesium alloys), copper, and alloys containing copper as a main component In addition, alloys containing zinc, tin, phosphorus, nickel, magnesium, silicon, and chromium (hereinafter referred to as copper alloys), titanium, and alloys containing titanium as a main component, as well as copper, manganese, silicon, magnesium, zinc, and nickel. (hereinafter referred to as titanium alloy). Among these, more preferred are iron, iron alloys, aluminum alloys, magnesium alloys, copper alloys, and titanium alloys, and even more preferred are iron alloys, aluminum alloys, and magnesium alloys.

Known methods can be used to roughen the surface of a metal member, such as (1) dipping in an erosive aqueous solution or suspension, (2) anodizing, (3) blasting, and Mechanical cutting by laser processing is an example. Of these, (1) immersion in an erosive aqueous solution or suspension or (2) anodization are particularly preferred as methods for roughening the surface of a metal member.

Before forming the finely uneven surface described above, the metal member is processed into a predetermined shape by plastic processing such as cutting, pressing, punching, cutting, grinding, and thinning processing such as electrical discharge machining. is preferred.

Note that a primer layer may be formed on the surface of a metal member that has been subjected to metal surface treatment. Although the material constituting the primer layer is not particularly limited, it is usually made of a primer resin material containing a resin component. The primer resin material is not particularly limited, and known materials can be used. Specifically, known polyolefin primers, epoxy primers, urethane primers, and the like can be mentioned. Although the method for forming the primer layer is not particularly limited, it can be formed, for example, by applying a solution of the above primer resin material or an emulsion of the above primer resin material to the metal member that has undergone the above surface treatment. Examples of the solvent used when preparing the solution include toluene, methyl ethyl ketone (MEK), dimethylphosphoramide (DMF), and the like. Examples of emulsion media include aliphatic hydrocarbon media and water.

The method for manufacturing a molded article and metal-resin composite according to the present embodiment may include a step of annealing the molded article and metal-resin composite. The optimum conditions for the annealing treatment are selected depending on the use or shape of the molded product and metal-resin composite, but the annealing temperature is within a temperature range of at least the glass transition temperature of the PAS resin, preferably at a temperature at least 10°C above the glass transition temperature. The temperature range is more preferably the glass transition temperature +30°C or higher. On the other hand, it is preferably in a range of 260°C or less, more preferably in a range of 240°C or less. Although the annealing time is not particularly limited, it is preferably in a range of 0.5 hours or more, and more preferably in a range of 1 hour or more. On the other hand, the duration is preferably 10 hours or less, and more preferably 8 hours or less. This range is preferable because the strain of the resulting molded product and metal-resin composite is reduced, and the crystallinity of the resin is improved, thereby further improving mechanical properties and chemical resistance. Although the annealing treatment may be performed in air, it is preferably performed in an inert gas such as nitrogen gas.

Applications of the molded product of the resin composition and the product of the metal-resin composite according to the present embodiment are not particularly limited, but include, for example, protection and support members for box-shaped electric/electronic component integrated modules, multiple individual semiconductors, Modules, sensors, LED lamps, connectors, sockets, resistors, relay cases, switches, coil bobbins, capacitors, variable capacitor cases, optical pickups, resonators, various terminal boards, transformers, plugs, printed circuit boards, tuners, speakers, microphones, Electrical and electronic parts such as headphones, small motors, magnetic head bases, power modules, terminal blocks, semiconductors, liquid crystals, FDD carriages, FDD chassis, motor brush holders, parabolic antennas, computer-related parts, etc.; VTR parts, TV parts , irons, hair dryers, rice cooker parts, microwave oven parts, audio parts, audio/visual equipment parts such as audio/laser discs, compact discs, DVD discs, Blu-ray discs, lighting parts, refrigerator parts, air conditioner parts, typewriter parts. , word processor parts, and parts for household and office appliances such as water heaters, bath water volume and temperature sensors; office computer-related parts, telephone-related parts, facsimile-related parts, and copying machine-related parts. , cleaning jigs, motor parts, lighters, typewriters, etc. Machine-related parts; microscopes, binoculars, cameras, clocks, etc. and other optical instruments, precision machinery-related parts; alternator terminals, alternator connectors, brush holders , slip rings, IC regulators, potentiometer bases for light dimmers, relay blocks, inhibitor switches, various valves such as exhaust gas valves, various pipes for fuel-related/exhaust systems/intake systems, air intake nozzles snorkels, intake manifolds, fuel pumps, engines. Cooling water joint, carburetor main body, carburetor spacer, exhaust gas sensor, cooling water sensor, oil temperature sensor, brake pad wear sensor, throttle position sensor, crankshaft position sensor, air flow meter, brake pad wear sensor, air conditioner thermostat base, Heating hot air flow control valve, brush holder for radiator motor, water pump impeller, turbine vane, wiper motor related parts, dust tributer, starter switch, ignition coil and its bobbin, motor insulator, motor rotor, motor core, starter relay, Transmission wire harnesses, window washer nozzles, air conditioner panel switch boards, fuel-related electromagnetic valve coils, fuse connectors, horn terminals, electrical component insulation boards, step motor rotors, lamp sockets, lamp reflectors, lamp housings, brake pistons, solenoids Examples include automobile/vehicle related parts such as bobbins, engine oil filters, and ignition device cases, and can also be applied to various other uses.

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to the Examples below.

<Examples 1 and 2 and Comparative Examples 1 and 2>
According to the composition components and amounts (all parts by mass) listed in Table 1, each material except glass fiber was uniformly mixed in a tumbler to obtain a compounded material. After that, this compounded material was introduced into the input port (top feeder) of a vented twin-screw extruder (Japan Steel Works, TEX30α), glass fiber was introduced from the side feeder, and the resin component output rate was 30 kg/hr, and the screw rotation The mixture was melt-kneaded at several 220 rpm and the resin temperature set at 320° C., and the strand-like material discharged from the discharge port was cut to obtain pellets.

In Table 1, a linear polyphenylene sulfide resin (melt viscosity (V6): 7 Pa·s) was used as the PPS resin (an example of a PAS resin).

In addition, the said PPS resin was manufactured by performing the following process 1 to process 3.

[Step 1]
Into a 150L autoclave equipped with stirring blades connected to a pressure gauge, a thermometer, a condenser, a decanter, and a rectification column, 35.868 parts by mass (244 parts by mole) of p-dichlorobenzene (hereinafter abbreviated as p-DCB) and 3.8 parts by mass of NMP. 420 parts by mass (34.5 parts by mole), 27.300 parts by mass of a 47.23 mass% NaSH aqueous solution (230 parts by mass as NaSH), and 18.533 parts by mass of a 49.21 mass% NaOH aqueous solution (228 parts by mass as NaOH). ) was charged, and the temperature was raised to 173° C. over 5 hours under a nitrogen atmosphere while stirring to distill off 27.300 parts by mass of water, and then the autoclave was sealed. p-DCB distilled azeotropically during dehydration was separated in a decanter and returned to the autoclave as needed. After the dehydration was completed, the inside of the autoclave was in a state where fine particulate anhydrous sodium sulfide composition was dispersed in p-DCB. Since the NMP content in this composition was 0.079 parts by mass (0.8 mol parts), 98 mol% (33.7 mol parts) of the charged NMP was the ring-opened form of NMP (4- It was shown that the sodium salt of (methylamino)butyric acid) (hereinafter abbreviated as "SMAB") was hydrolyzed. The amount of SMAB in the autoclave was 0.147 mole parts per mole of sulfur atoms present in the autoclave. Since the theoretical dehydration amount when all of the charged NaSH and NaOH are converted to anhydrous Na ₂ S is 27.921 parts by mass, of the 0.878 parts by mass (48.8 mol parts) of the remaining water in the autoclave, 0.609 parts by mass (33.8 parts by mole) is consumed in the hydrolysis reaction between NMP and NaOH and does not exist in the autoclave as water, and the remaining 0.269 parts by mass (14.9 parts by mole) is This indicated that the substance remained in the autoclave in the form of water or crystallized water. The amount of water in the autoclave was 0.065 mol per mol of sulfur atoms present in the autoclave.

[Step 2]
After the completion of the dehydration step, the internal temperature was cooled to 160°C, 46.343 parts by mass (467.5 mol parts) of NMP was charged, and the temperature was raised to 185°C. The amount of water in the autoclave was 0.025 mol per mol of NMP charged in step 2. When the gauge pressure reached 0.00 MPa, the valve connected to the rectification column was opened, and the internal temperature was raised to 200° C. over 1 hour. At this time, cooling and valve opening were controlled so that the temperature at the outlet of the rectifying column was 110° C. or less. The distilled mixed vapor of p-DCB and water was condensed in a condenser and separated in a decanter, and the p-DCB was returned to the autoclave. The amount of distilled water was 0.228 parts by mass (12.7 parts by mole).

[Step 3]
The moisture content in the autoclave at the start of step 3 was 0.041 parts by mass (2.3 parts by mole), 0.005 mol per mol of NMP charged in step 2, and 0.005 mol per mol of sulfur atoms present in the autoclave. It was 0.010 mol. As in Step 1, the amount of SMAB in the autoclave was 0.147 mol per mol of sulfur atoms present in the autoclave. Next, the internal temperature was raised from 200°C to 230°C over 3 hours, stirred at 230°C for 1 hour, then heated to 250°C, and stirred for 1 hour. The gauge pressure at the internal temperature of 200°C was 0.03 MPa, and the final gauge pressure was 0.40 MPa. After cooling, 0.650 parts by mass of the obtained slurry was poured into 3 parts by mass (3 L parts) of water, stirred at 80° C. for 1 hour, and then filtered. This cake was stirred again for 1 hour with 3 parts by mass (3 L parts) of warm water, washed, and then filtered. This operation was repeated four times. To this cake, 3 parts by mass (3 liters) of warm water and acetic acid were added again to adjust the pH to 4.0, stirred for 1 hour, washed, and filtered. This cake was again stirred for 1 hour with 3 parts by mass (3 liters) of warm water, washed, and then filtered. This operation was repeated twice. The mixture was dried overnight at 120° C. using a hot air dryer to obtain a white powdery PPS resin. The melt viscosity of this PPS resin at 300°C was 7 Pa·s. The non-Newtonian index was 1.07.

In the manner described above, PPS resins used in Examples and Comparative Examples were manufactured.

As the thermoplastic elastomer, "Bond First-7L" (ethylene-glycidyl dimethacrylate-vinyl acetate) manufactured by Sumitomo Chemical Co., Ltd. was used.

Glass fiber and calcium carbonate were used as inorganic fillers. As the glass fiber, "T-717H" manufactured by Nippon Electric Glass Co., Ltd. (fiber length 3 mm, average diameter 10 μm) was used. As the calcium carbonate, "Grade 1 calcium carbonate" manufactured by Sankyo Seifun Co., Ltd. (average particle size 6.4 μm) was used.

As the mold release agent, high-density polyethylene wax "LUWAX AH-6" manufactured by BASF was used.

As shown in Table 1, compared to Example 1 and Comparative Example 1, Example 2 and Comparative Example 2 differ in that the prescribed amount (blended amount) of the thermoplastic elastomer is larger. Furthermore, compared to Example 1 and Comparative Example 1, Example 2 and Comparative Example 2 differ in that the prescribed amount (compounding amount) of the mold release agent is larger.

In the example, the pellets of the above resin composition were molded into an injection molding machine (SE75-DZU C110) manufactured by Sumitomo Heavy Industries, Ltd. using a vent type injection molding unit (screw diameter: 28 mmΦ, equipped with a vent port) manufactured by Nihon Yuki without pre-drying. ), and in the comparative example, an injection molding machine manufactured by Sumitomo Heavy Industries, Ltd. (SE75-DZU C110, screw diameter: 28 mmΦ, no vent port) was used to produce a molded product. In Examples 1 and 2, the resin composition was supplied to the cylinder by pouring it into a hopper from a screw feeder, thereby providing starvation supply.

Note that, as described above, the vent port is installed between the upstream part of the cylinder and the downstream part of the cylinder.

The test pieces are a cup-shaped first test piece (see molded body 51 shown in FIG. 2) molded from a resin composition by injection molding using separate molds, and a metal molded by insert injection molding as injection molding. A second test piece (see metal-resin composite 7 shown in FIG. 3) which is a resin composite (composite molded product) was created. As shown in FIG. 3, the second test piece (metal-resin composite 7) is placed in a metal piece of a predetermined size (an example of a metal member, see metal piece 6 in FIG. 3) placed in a predetermined mold. On the other hand, a resin composition is injection molded, and a plate-shaped molded body of the resin composition (see molded body 52 in FIG. 3) is bonded to a metal piece. In the present Examples and Comparative Examples, the second test piece was produced using a mold conforming to the ISO19095 Type B mold. In the second test piece, the metal piece 6 is an alumite-treated plate-shaped aluminum piece. The gate of the mold used to manufacture the second test piece is provided with pin gates 98 of 1 mmΦ in two places on the sides of the overlapping part of the metal piece 6 and molded body 52 in FIG. 3, and the shape of the gas vent slit 99 is The land length is 10 mm, and the thickness is 5 μm. As shown in FIG. 2, the gates 90 of the mold used to manufacture the first test piece were pin gates with a diameter of 1 mm at four locations at 90° intervals in the circumferential direction of the cup-shaped opening edge of the molded body 51. 90a, and the shape of the gas vent slit 97 is 10 mm in width and land length, and 5 μm in thickness.

When molding the first test piece and the second test piece, in order to strictly evaluate the influence of gas contamination on the mold, in the mold used for each mold, the gas inside the mold was To prevent leakage from the gaps (parting lines) around the mold insert, these gaps were sealed to prevent gas from escaping.

When molding the first test piece and the second test piece, evaluations were made regarding molding defects and mold maintenance frequency. The evaluation results are shown in Table 3.

In Table 3, the "number of continuous shots that can be molded" is the number of times the first test piece can be successfully molded without mold maintenance without molding defects after repeated injection molding. .

In Table 3, "flow end density of molded article" is the density of the molded article in the portion immediately before the gas vent slit in the first test piece.

In Table 3, "Gas vent stain" is the result of visually inspecting the gas vent slit of the mold after molding the first test piece 50 times (after 50 shots). In the row of "Gas vent dirt", "A" is a state in which no deposits (dirt) are visible, "B" is a state in which minute viscous liquid adhesion is visible, and "C" is a state in which colored viscous liquid or part of it is visible. Indicates that it has been determined that carbonization is visible. These judgment results mean good to bad in the order of A, B, and C.

In Table 3, "Gas vent oligomer adhesion amount" refers to the amount of adhesion on the gas vent slit of the mold after molding the first test piece 50 times (after 50 shots), which is collected by washing with a solvent (tetrahydrofuran (THF) 2 mL). This is the GPC area value of the total amount of retention time deposits equivalent to a polystyrene equivalent molecular weight of 400 to 8000, determined by analyzing the cleaning solution by gel permeation chromatography (GPC).The larger the value, the more deposits are on the gas vent slit. , which means the gas vent slit is dirtier.

The GPC measurement conditions are as follows. Two ShodexGPC KF-G+LF-804 columns were used. The column temperature was 40°C. THF was used as the solvent, and the eluent rate was 1 mL/min. Ultraviolet light with a wavelength of 254 nm was used for detection.

In Table 3, "insert metal bonding strength average (1st to 10th shots)" refers to the bonding strength in the tensile shear test between the metal piece and the resin composition in the 10 second test pieces from the 1st to 10th shots. This is the average value (arithmetic mean) of intensity. Note that the metal bonding strength was evaluated in accordance with ISO19095. Similarly, "insert metal bonding strength average (1000th to 1009th shot)" is the bonding strength in the tensile shear test between the metal piece and the resin composition in the 10 second test pieces from 1000th to 1009th shot. is the average value of "Insert metal bonding strength standard deviation (1st to 10th shot)" and "Insert metal bonding strength standard deviation (1000 to 1009th shot)" are the standard deviations of the bonding strength of the 10 second test pieces, respectively. . It is preferable that the insert metal bonding strength has a large average value and a small standard deviation.

From the results shown in Table 3, the injection molding method of the example has a larger number of continuous shots that can be molded than the injection molding method of the comparative example. Therefore, it is considered that molding defects can be reduced. There is no significant difference in the density at the flow end of the molded product between Examples and Comparative Examples, and when the components volatilized from the resin composition in the cylinder are discharged from the vent port as in the injection molding method of this embodiment. Even if it is, it is thought that it will not cause any defects that would reduce the density of the molded product.

Regarding gas vent stains and gas vent oligomer adhesion amount, the injection molding method of the example is better than the comparative example, and therefore, as mentioned above, the injection molding method of the example is considered to increase the number of continuous shots. . That is, in the injection molding method of the embodiment, the gas vent slit of the mold is less likely to become contaminated, and therefore the gas vent slit of the mold is less likely to be clogged (hardly blocked), making it possible to increase the number of consecutive shots. The reason why the gas vent slit in the mold is less likely to become dirty is because the volatile components from the resin composition inside the cylinder are discharged from the vent port, and the volatile components can be sufficiently removed from the resin composition inside the cylinder. It is possible to suppress the supply of gas into the mold (injection together with the resin composition), and also to reduce the amount of gas generated from the resin composition in the mold (hereinafter referred to as the effect of exhaust from the vent port). This is thought to be due to the following: That is, in the injection molding method of this embodiment, dirt on the mold can be reduced and the frequency of maintenance of the mold can be reduced. Furthermore, by reducing the frequency of mold maintenance, molding defects can also be reduced.

Regarding the insert metal bonding strength, the strength of Example 1 is higher than that of Comparative Example 1, and the strength of Example 2 is higher than that of Comparative Example 2. That is, if the formulation (mixing) of the resin composition is similar, the strength of the insert molded product manufactured by the injection molding method of this embodiment will be high. This is because the gas generation and amount inside the mold are reduced due to the effect of exhaust from the vent port as described above, and the metal-resin composition interface is free from water and PAS contained in the resin composition. This is thought to be due to the fact that contamination by low molecular weight components derived from the resin can be suppressed. That is, in the insert molding method as the injection molding method of the present embodiment, it is possible to suppress contamination at the interface of the metal-resin composition and increase the bonding strength of the metal-resin composition. Note that the standard deviation from the 1st to the 10th shot or from the 1000th to the 1009th shot is also better in the example than in the comparative example. From this point of view as well, it can be said that the injection molding method of this embodiment enables the production of molded products with little variation in quality, that is, it is possible to reduce molding defects.

As described above, the injection molding method according to the present embodiment reduces molding defects of molded products and maintenance frequency of molding molds in a method of injection molding a resin composition containing a PAS resin and a thermoplastic elastomer. It is possible. Further, by using the injection molding method according to the present embodiment, it is possible to realize a method for manufacturing a molded article of a resin composition containing a PAS resin and a thermoplastic elastomer. Further, by using the injection molding method according to the present embodiment, it is possible to realize a method for manufacturing a metal resin composite of a metal member and a resin composition containing a PAS resin and a thermoplastic elastomer.

As described above, in the injection molding method of a resin composition containing a PAS resin, an injection molding method that can reduce molding defects and the frequency of mold maintenance, a method for manufacturing a molded product of a resin composition, and a metal-resin composite A method for manufacturing a body can be provided.

Note that the embodiments and examples disclosed in this specification are illustrative, and the embodiments of the present invention are not limited thereto, and can be modified as appropriate without departing from the purpose of the present invention. .

The present invention is applicable to injection molding methods, molded article manufacturing methods, and metal resin composite manufacturing methods.

1 : Supply mechanism 10 : Supply speed control mechanism 2 : Cylinder 20 : Vent 21 : Mixing part 22 : Nozzle 3 : Screw 31 : First screw part 32 : Second screw part 4 : Heater 5 : Molded object 51 : Molded object 52 : Molded object 6 : Metal piece (metal member)
7: Metal resin composite 9: Mold 90: Gate 90a: Pin gate 91: First mold 92: Second mold 95: Slit piece 96: Slit piece 97: Gas vent slit 98: Pin gate 99: Vent slit C: Control Department

Claims (10)

A cylinder having a nozzle at its tip and capable of heating control divided into at least two blocks in the longitudinal direction; a screw placed within the cylinder and capable of compressing and melting, metering and injecting resin supplied from the base; and the cylinder. In an injection molding method using an injection unit equipped with a vent port disposed in the middle of the longitudinal direction,
a supply step of supplying a resin composition containing a polyarylene sulfide resin and a thermoplastic elastomer to the cylinder of the injection unit;
a plasticizing step of plasticizing the resin composition in the cylinder by maintaining the cylinder at 290° C. or higher;
a discharge step of discharging the components volatilized from the resin composition in the plasticizing step from the vent port;
an injection step of injecting the resin composition from the cylinder with the screw;
a molding step of molding the resin composition injected in the injection step with a mold;
Injection molding methods, including: The injection molding method according to claim 1, wherein in the molding step, the mold is maintained at a temperature of 100° C. or higher when receiving the resin composition injected from the cylinder. The injection molding method according to claim 1 or 2, wherein the resin composition contains the thermoplastic elastomer in an amount of 0.5 parts by mass or more and 20 parts by mass or less based on 100 parts by mass of the polyarylene sulfide resin. The injection molding method according to claim 1 or 2, wherein the resin composition further contains an inorganic filler of 50 parts by mass or more and 150 parts by mass or less based on 100 parts by mass of the polyarylene sulfide resin. The injection molding method according to claim 1 or 2, wherein the resin composition further contains 0.01 parts by mass or more and 5 parts by mass or less of a mold release agent based on 100 parts by mass of the polyarylene sulfide resin. The injection molding method according to claim 1 or 2, wherein the supplying step is performed so that the inside of the cylinder is starved. 3. The injection molding method according to claim 1, wherein in the plasticizing step, the temperature of the cylinder downstream of the vent port is maintained lower than the temperature of the cylinder upstream of the vent port. The injection molding method according to claim 1 or 2, wherein the volatilized component is sucked and discharged from the vent port. A method for producing a molded article of the resin composition using the injection molding method according to claim 1 or 2. A method for producing a metal-resin composite of the resin composition and a metal member using the injection molding method according to claim 1 or 2, comprising:
A method for manufacturing a metal-resin composite including a step of arranging the metal member in the mold.

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