Method for producing aromatic thioether sulfone polymer, composition and molded article

Abstract

Provided are methods for producing an aromatic thioether sulfone polymer, an aromatic thioether sulfone polymer composition, and an aromatic thioether sulfone polymer molded article, which all have a high refractive index and have less coloring and high transparency. In further detail, this method for manufacturing an aromatic thioether sulfone polymer is characterized by polymerizing, in a hydrous sulfone-based solvent, a dihalo aromatic compound and (i) an alkali metal sulfide or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide.

Description

Technical Field

[0001] The present invention relates to a method for producing an aromatic thioether sulfone polymer, a composition, and a molded article.

Background Art

[0002] In recent years, resin materials have been widely used for optical materials such as optical lenses, prism sheets, and components for organic light-emitting diode devices (OLEDs) because of their excellent processability and productivity. Further, due to the trend of miniaturization and weight reduction of optical members, resin materials having a high refractive index are required. The general refractive index of conventional resins is 1.30 to 1.70, and there are almost no general-purpose materials having a refractive index exceeding 1.70.

[0003] A general approach for increasing the refractive index of a resin is to introduce a substituent having a high molar refraction, a small molar volume, and a large specific gravity into the molecule according to the Lorentz-Lorenz equation. That is, the introduction of a halogen atom or a sulfur atom is considered effective. Sulfur atoms have a high polarizability, stability, and ease of introduction into polymers, and various sulfur-containing resins for optical materials have been reported so far. For example, a compound having a thiourethane skeleton is disclosed as a sulfur-containing resin. However, this compound has low heat resistance and has problems in use under high-temperature conditions (Patent Documents 1, 2, and 3).

[0004] On the other hand, aromatic polythioethers are promising high-refractive materials because they have a high sulfur content in the resin skeleton and a very high density. In particular, an aromatic thioether sulfone polymer is an amorphous resin, so it has high transparency, and further has a high glass transition temperature of about 220°C, so it is expected to be an optical material that can be used even under high-temperature conditions. However, in the conventional production methods of aromatic thioether sulfone polymers reported so far, the obtained resins are colored and lack transparency, so their use as optical materials has been avoided (Patent Documents 4 and 5).

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Laid-Open No. 09-324023 [Patent Document 2] Japanese Patent Laid-Open No. 2006-003624 [Patent Document 3] Japanese Patent Laid-Open No. 2009-256692 [Patent Document 4] Japanese Patent Laid-Open No. 4-275335 [Patent Document 5] Pamphlet of International Publication No. 90 / 03210 [Summary of the Invention] [Problems to be Solved by the Invention]

[0006] Therefore, the problem to be solved by the present invention is to provide an aromatic thioether sulfone polymer, a composition, and a method for producing a molded article, which have a high refractive index, little coloring, and high transparency. [Means for Solving the Problems]

[0007] As a result of intensive studies to solve the above problems, the present inventors have found that an aromatic thioether sulfone polymer having a high refractive index, little coloring, and high transparency can be provided by polymerizing a dihalo aromatic compound with (i) an alkali metal sulfide or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in the presence of a hydrous sulfone-based solvent.

[0008] That is, the present disclosure relates to a method for producing an aromatic thioether sulfone polymer, which comprises polymerizing a dihalo aromatic compound with (i) an alkali metal sulfide or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in a hydrous sulfone-based solvent.

[0009] In the present disclosure, a polymer having repeating units 2 to 40 (a mixture of dimers to 40-mers) may be referred to as an "oligomer". [Advantages of the Invention]

[0010] According to the present invention, it is possible to provide a method for producing an aromatic thioether sulfone polymer having a high refractive index, little coloring, and high transparency.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention (hereinafter referred to as "the present embodiment") will be described in detail. However, the present invention is not limited to the following description and can be variously modified and implemented within the scope of the gist thereof.

[0012] <Method for Producing Aromatic Thioether Sulfone Polymer> The method for producing an aromatic thioether sulfone polymer according to the first embodiment of the present disclosure is characterized in that a dihaloaromatic compound and (i) an alkali metal sulfide or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide are polymerized in a water-containing sulfone-based solvent.

[0013] Further, the method for producing an aromatic thioether sulfone polymer according to the second embodiment of the present disclosure is as follows. A step (1) of polymerizing a dihaloaromatic compound and (i) an alkali metal sulfide or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in a water-containing sulfone-based solvent to obtain a crude reaction mixture. A step (2) of crushing the crude reaction mixture. It has a step (3) of bringing the crushed crude reaction mixture into contact with a polar organic solvent and then performing solid-liquid separation to obtain a solid-phase component (A). This will be described in detail below.

[0014] Step (1) The water-containing sulfone-based solvent used in this embodiment is a mixture of water and a sulfone-based solvent. The sulfone-based solvent is a compound having one or more sulfone groups. Examples thereof include diphenyl sulfone (DPS), dimethyl sulfoxide, diethyl sulfone, diisopropyl sulfone, sulfolane (1,1-dioxothiolane), and the like. Particularly, DPS is preferable from the viewpoints of thermal stability, smoothness of the polymerization reaction, and economy. From the viewpoint of the reaction rate of polymerization, the water content of the water-containing sulfone solvent is preferably 1 mol / kg or more, more preferably 3 mol / kg or more, preferably 20 mol / kg or less, and more preferably 10 mol / kg or less with respect to the sulfone-based solvent.

[0015] The dihaloaromatic compound used in this embodiment is, for example, a halogenated aromatic compound having two halogen atoms directly bonded to an aromatic ring. Specifically, p-dichlorodiphenyl sulfone, o-dichlorodiphenyl sulfone, m-dichlorodiphenyl sulfone, p-dibromodiphenyl sulfone, o-dibromodiphenyl sulfone, m-dibromodiphenyl sulfone, p-diiododiphenyl sulfone, o-diiododiphenyl sulfone, m-diiododiphenyl sulfone, p-dichlorobenzene, o-dichlorobenzene, m-dichlorobenzene, dibromobenzene, diiodobenzene, tribromobenzene, dibromonaphthalene, dichlorodiphenylbenzene, dibromodiphenylbenzene, dichlorobenzophenone, dibromobenzophenone, dichlorodiphenyl ether, dibromodiphenyl ether, dichlorodiphenyl sulfide, dibromodiphenyl sulfide, dichlorobiphenyl, dibromobiphenyl and other dihaloaromatic compounds and mixtures thereof may be mentioned, and these compounds may be block copolymerized. Among these, dihalogenated diphenyl sulfones are preferable, and those containing 80 mol% or more of p-dichlorodiphenyl sulfone are particularly preferable.

[0016] Furthermore, dihaloaromatic compounds having a functional group with active hydrogen such as an amino group, a thiol group, a hydroxyl group, etc. can be mentioned. Specifically, dihaloanilines such as 2,6-dichloroaniline, 2,5-dichloroaniline, 2,4-dichloroaniline, 2,3-dichloroaniline, etc.; dihaloaminodiphenyl ethers such as 2,2'-diamino-4,4'-dichlorodiphenyl ether, 2,4'-diamino-2',4-dichlorodiphenyl ether, etc. and compounds in which the amino group in these mixtures is replaced by a thiol group or a hydroxyl group, etc. are exemplified.

[0017] In addition, active hydrogen-containing dihaloaromatic compounds in which the hydrogen atom bonded to the carbon atom forming the aromatic ring in these active hydrogen-containing dihaloaromatic compounds is substituted with another inert group, for example, a hydrocarbon group such as an alkyl group, can also be used.

[0018] Among these various active hydrogen-containing dihaloaromatic compounds, preferred are active hydrogen-containing dihaloaromatic compounds, and particularly preferred is dichloroaniline.

[0019] Examples of the dihaloaromatic compound having a nitro group include dihalonitrobenzenes such as 2,4-dinitrochlorobenzene and 2,5-dichloronitrobenzene; dihalonitrodiphenyl ethers such as 2-nitro-4,4'-dichlorodiphenyl ether; dihalonitrodiphenyl sulfones such as 3,3'-dinitro-4,4'-dichlorodiphenyl sulfone; mono- or dihalonitropyridines such as 2,5-dichloro-3-nitropyridine and 2-chloro-3,5-dinitropyridine; or various dihalonitronaphthalenes; dihalofluorenes such as 9,9-bis(4-chlorophenyl)fluorene, 9,9-bis(4-bromophenyl)fluorene, 9,9-bis(4-iodophenyl)fluorene, 9,9-bis(4-chloro-3-methylphenyl)fluorene, 9,9-bis(4-bromo-3-methylphenyl)fluorene, 9,9-bis(4-iodo-3-methylphenyl)fluorene, 9,9-bis(4-chloro-3-ethylphenyl)fluorene, 9,9-bis(4-bromo-3-ethylphenyl)fluorene, 9,9-bis(4-iodo-3-ethylphenyl)fluorene, 9,9-bis(4-chloro-3-isopropylphenyl)fluorene, 9,9-bis(4-bromo-3-isopropylphenyl)fluorene, 9,9-bis(4-iodo-3-isopropylphenyl)fluorene, 9,9-bis(4-chloro-3,5-dimethylphenyl)fluorene, 9,9-bis(4-bromo-3,5-dimethylphenyl)fluorene, and 9,9-bis(4-iodo-3,5-dimethylphenyl)fluorene.

[0020] In this embodiment, an alkali metal sulfide, or an alkali hydrosulfide and an alkali metal hydroxide (hereinafter sometimes referred to as a sulfidizing agent) are used as raw materials.

[0021] In this embodiment, examples of the alkali metal sulfide include lithium sulfide, sodium sulfide, rubidium sulfide, cesium sulfide, and mixtures thereof. Such alkali metal sulfides can be used as hydrates, aqueous mixtures, or anhydrides. Further, the alkali metal sulfide can also be obtained by reacting an alkali metal hydrosulfide with an alkali metal hydroxide. Usually, a small amount of an alkali metal hydroxide may be added to react with trace amounts of alkali metal hydrosulfide and alkali metal thiosulfate present in the alkali metal sulfide.

[0022] Examples of the alkali metal hydrosulfide include lithium hydrosulfide, sodium hydrosulfide, rubidium hydrosulfide, cesium hydrosulfide, and mixtures thereof. Such alkali metal hydrosulfides can be used as hydrates, aqueous mixtures, or anhydrides.

[0023] The alkali metal hydrosulfide is used together with an alkali metal hydroxide. Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, etc. These may be used alone or in combination of two or more. Among these, lithium hydroxide, sodium hydroxide, and potassium hydroxide are preferred because they are easily available, and sodium hydroxide is particularly preferred.

[0024] The amount of the sulfidizing agent used in this step is preferably 0.1 mol / kg, more preferably 0.3 mol / kg, preferably 20 mol / kg or less, and more preferably 10 mol / kg or less, relative to the sulfone-based solvent. When it is less than 0.1 mol / kg, the productivity of the polymer decreases, which is disadvantageous from an economic perspective. On the other hand, when it is more than 20 mol / kg, the viscosity of the system during the reaction increases, making stirring difficult and potentially reducing the yield.

[0025] In this process, the molar ratio of the dihaloaromatic compound to the sulfidizing agent is preferably in the range of 0.95 to 1.2 (mol / mol), more preferably in the range of 1.00 to 1.10 (mol / mol). When it is less than 0.95 (mol / mol), decomposition reaction may occur or the thermal stability of the resulting aromatic copolymer may become poor. When it is greater than 1.2 (mol / mol), the polymerization reaction may hardly proceed and it may be difficult to increase the molecular weight.

[0026] In the presence of the above-mentioned water-containing sulfone-based solvent, the polymerization conditions of the above-mentioned sulfidizing agent and the dihaloaromatic compound are generally a temperature of 150 to 330 °C, and the pressure should be in a range that can substantially retain the polymerization solvent and the dihaloaromatic compound as the polymerization monomer in the liquid layer. Generally, it is selected from the range of 0.1 to 20 MPa, preferably 0.1 to 2 MPa. The reaction time varies depending on the temperature and pressure, but generally it is in the range of 10 minutes to 72 hours, preferably in the range of 1 hour to 10 hours. To obtain an aromatic thioether sulfone polymer with a higher molecular weight, it is preferable to use a two-stage or more reaction temperature profile. When performing this two-stage operation, the first stage is preferably carried out at 90 °C or higher because the reaction rate is not too small and it is practical. It is preferably carried out at a temperature of 180 °C or lower because a sufficiently high molecular weight aromatic thioether sulfone polymer can be obtained and the side reaction rate does not increase. Furthermore, 120 to 160 °C is particularly preferable. Then, the temperature is raised, and the final stage of the reaction is preferably carried out at 180 to 300 °C for 1 to 50 hours. The above temperature range is preferably such that the reaction temperature is 180 °C or higher because it is easy to obtain an aromatic thioether sulfone polymer with a sufficiently high molecular weight, and it is preferably to react at 300 °C or lower because side reactions such as depolymerization hardly occur and it is easy to stably obtain a high molecular weight product.

[0027] This embodiment also includes a form in which the crude reaction product is obtained by reacting while continuously or intermittently adding the dihaloaromatic compound and the water-containing sulfone-based solvent in the presence of the sulfidizing agent and the water-containing sulfone-based solvent.

[0028] Thus, in a hydrous sulfonic solvent, by subjecting a dihalo aromatic compound and a sulfidizing agent to a polymerization reaction, an aromatic thioether sulfone polymer is obtained as a product, and in addition, oligomers are also by-produced. As substances contained in the crude reaction mixture after the reaction, there may also be contained, for example, by-products such as alkali metal-containing inorganic salts and terminal SH group-containing compounds, and unreacted raw materials.

[0029] Step (2) Step (2) is a step of crushing the crude reaction mixture obtained in step (1).

[0030] The method for crushing the crude reaction mixture in this step is not particularly limited, and known methods and apparatuses can be used. For example, known crushing means such as a cutter mill, a comb-blade crusher, a hammer mill, a jaw crusher, a rotor mill, a cutting mill, a knife mill, a disk mill, a cryogenic crusher, etc. can be used. Further, after crushing by these means, sieving may be performed using a filter having a specific mesh size.

[0031] The size of the crushed product obtained in this step is not particularly limited as long as the effects of the present invention are not impaired. For example, the average particle diameter (D 50 ) is preferably 1 μm or more, more preferably 10 μm or more, preferably 2000 μm or less, more preferably 1000 μm or less, and even more preferably 500 μm or less. If it is above such a range, the washing efficiency may deteriorate in subsequent steps. Also, if it is below such a range, it may adhere during washing in subsequent steps, or the workability may decrease during filtration or drying. The average particle diameter (D 50 ) is a value determined based on the particle size distribution measured according to a conventional method using a laser diffraction / scattering particle size distribution analyzer (Microtrac MT3300EXII).

[0032] Step (3) Step (3) is a step of bringing the crushed crude reaction mixture into contact with a polar organic solvent and then performing solid-liquid separation to obtain a solid phase component (A).

[0033] Examples of polar organic solvents that can be used in this process include alcohols having 10 or fewer carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, t-butyl alcohol, ethylene glycol, propylene glycol, trimethylolpropane, benzyl alcohol; alcohols having 10 or fewer carbon atoms containing an ether bond such as 2-methoxyethyl alcohol, 2-ethoxyethyl alcohol, 1-methoxy-2-propyl alcohol, 1-ethoxy-2-propyl alcohol, 3-methoxy-1-butyl alcohol, 2-isopropoxyethyl alcohol; alcohols having 10 or fewer carbon atoms containing a ketone group such as 3-hydroxy-2-butanone; alcohols having 10 or fewer carbon atoms containing an ester group such as methyl hydroxyisobutyrate; ketones such as methyl phenyl ketone; amides, ureas and lactams such as formamide, acetamide, N-methylformamide, N,N-dimethylacetamide, tetramethylurea, N-methyl-2-pyrrolidone, 2-pyrrolidone, N-methyl-ε-caprolactam, ε-caprolactam, hexamethylphosphoramide, N-dimethylpropyleneurea, 1,3-dimethyl-2-imidazolidinone; sulfolanes such as sulfolane, dimethyl sulfolane; nitriles such as benzonitrile and mixtures thereof. Further, mixtures of two or more of the above organic solvents may be used. Furthermore, the polar organic solvent may contain water.

[0034] In the present embodiment, from the viewpoint of efficiently removing impurities such as remaining oligomers, it is preferable to use alcohols or ketones as the polar organic solvent, and particularly preferably acetone. Also, from the same viewpoint, it is more preferable to use water-containing alcohol because salts generated during polymerization can be efficiently removed. When using water-containing alcohol, the concentration of the alcohol solvent in the aqueous solution is not particularly limited, but the amount of the alcohol solvent is preferably in the range of 1000 parts by mass or less, more preferably in the range of 500 parts by mass or less, preferably 25 parts by mass or more, and more preferably 45 parts by mass or more with respect to 100 parts by mass of water.

[0035] When contacting the crushed crude reaction mixture with the polar organic solvent in this step, the conditions are not particularly limited, but are preferably in the range of 10°C or higher, more preferably 20°C or higher, to preferably 100°C or lower, more preferably 70°C or lower, and the pressure (gauge pressure) is less than 0.1 MPa, preferably in the range of 0.05 MPa or lower, and more preferably under atmospheric pressure.

[0036] There is no particular limitation on the amount of the polar organic solvent used in this step. However, from the viewpoint of achieving suitable washing efficiency, based on 100 parts by mass of the aromatic thioether sulfone polymer (theoretical yield) contained in the crushed crude reaction mixture, it is preferably 50 parts by mass or more, more preferably 100 parts by mass or more, still more preferably 200 parts by mass or more, to preferably 10,000 parts by mass or less, more preferably 5,000 parts by mass or less, and still more preferably 2,000 parts by mass or less.

[0037] The method for solid-liquid separation in this step is not particularly limited, and known apparatuses and methods can be used. For example, appropriate methods such as vacuum distillation, centrifugation, screw decanter, vacuum filtration, and pressure filtration can be selected. Further, these methods can be combined or repeated. Additionally, this step of solid-liquid separation after contacting with the polar organic solvent can be repeated two or more times.

[0038] The degree of separation and removal of the water-containing sulfone-based solvent is not particularly limited, but the proportion of the solid content (solid content concentration) in the solid phase component (A) is preferably 40 parts by mass or more, more preferably 50 parts by mass or more, still more preferably 55 parts by mass or more, based on 100 parts by mass of the solid phase component (A). The upper limit is not limited, but is preferably 100 parts by mass or less, more preferably less than 100 parts by mass, and still more preferably 99 parts by mass or less.

[0039] The amount of oligomer contained in the solid component (A) is preferably 3.5 parts by mass or less, more preferably 2 parts by mass or less, and even more preferably 1.8 parts by mass or less with respect to 100 parts by mass of the solid component (A). In such a range, the resulting aromatic thioether sulfone polymer is excellent in melt stability. The measurement method of the oligomer content can be measured by the method described in the examples.

[0040] The filtered aromatic thioether sulfone polymer is recovered, and then it may be directly dried and used as an aromatic thioether sulfone polymer powder, or it may be further washed with warm water, hot water, etc., followed by solid-liquid separation and drying to prepare a powdery or granular aromatic thioether sulfone polymer. Furthermore, the obtained powdery or granular aromatic thioether sulfone polymer can be heat-treated to obtain a crosslinked aromatic thioether sulfone polymer.

[0041] The aromatic thioether sulfone polymer obtained by the above production method is excellent in refractive index. Specifically, the refractive index is preferably in the range of 1.65 or more, more preferably 1.7 or more, and preferably 1.8 or less. In the present disclosure, the refractive index is a value measured at room temperature (23 °C) and 589 nm by a method in accordance with JIS K 7142 using an aromatic thioether sulfone polymer melt-molded to a thickness of 40 μm as a test piece.

[0042] In addition, the aromatic thioether sulfone polymer obtained by the above production method is excellent in transparency. Specifically, the lightness is preferably in the range of 85 or more, more preferably 90 or more, and preferably 99.9 or less, and the transmittance is preferably in the range of 70% or more, more preferably 80% or more, and preferably 99.9% or less. In the present disclosure, the lightness is the L value obtained by reflection measurement using a colorimetric difference meter in accordance with JIS Z 8781-4 with a white plate as the background using an aromatic thioether sulfone polymer melt-molded to a thickness of 40 μm as a test piece, and the transmittance is the transmittance measured at a wavelength of 450 nm using an ultraviolet-visible spectrophotometer with the same test piece. * value, and the transmittance is the transmittance measured at a wavelength of 450 nm using the same test piece with an ultraviolet-visible spectrophotometer.

[0043] In addition, the aromatic thioether sulfone polymer obtained by the above production method has a low oligomer content. Specifically, the oligomer content per 100 parts by mass is preferably 3.5 parts by mass or less, more preferably 2 parts by mass or less, and even more preferably 1.8 parts by mass or less. In such a range, the amount of gas generated when the polymer is heated and melted can be reduced. The oligomer content of the polymer in the present disclosure can be measured by the method described in the examples.

[0044] In addition, the aromatic thioether sulfone polymer obtained by the above production method is excellent in melt stability, and thus has a small viscosity change rate when staying. Specifically, the viscosity change rate is preferably 10% or less, more preferably 8% or less. The viscosity change rate in the present disclosure can be measured by the method described in the examples.

[0045] <Method for producing a composition> The method for producing the composition according to the present embodiment includes a step of blending the aromatic thioether sulfone polymer produced by the above method with other substances and melt-kneading them.

[0046] The aromatic thioether sulfone polymer obtained by the production method according to this embodiment can contain additives such as a release agent, a colorant, a heat stabilizer, an ultraviolet stabilizer, a foaming agent, a rust preventive agent, a flame retardant, a lubricant, a coupling agent, and a filler as other substances within the range not impairing the effects of the present invention, and can be used as a composition. As the filler, known and commonly used materials can be used as long as they do not impair the effects of the present invention, and examples include inorganic fillers in various shapes such as fibrous ones and non-fibrous ones such as granular and plate-like ones. 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, and natural fiber can be used, and non-fibrous fillers such as glass beads, glass flakes, barium sulfate, clay, pyrophyllite, bentonite, sericite, mica, talc, attapulgite, ferrite, calcium silicate, calcium carbonate, glass beads, zeolite, milled fiber, and calcium sulfate can also be used.

[0047] The aromatic thioether sulfone polymer obtained by the production method according to this embodiment can further be used as a composition by mixing the following synthetic resins and elastomers as other substances within the range not impairing the effects of the present invention. Examples of these synthetic resins include polyester, polyamide, polyimide, polyetherimide, polycarbonate, polyphenylene ether, polysulfone, polyethersulfone, polyetheretherketone, polyetherketone, polyarylene, polyarylene sulfide, polyethylene, polypropylene, polytetrafluoroethylene, polyvinylidene fluoride, polystyrene, ABS resin, epoxy resin, silicone resin, phenol resin, urethane resin, liquid crystal polymer, etc., and examples of the elastomer include polyolefin rubber, fluororubber, silicone rubber, etc.

[0048] As a method for blending and kneading the above components with the aromatic thioether sulfone polymer obtained by the production method according to the present embodiment, there is no particular limitation. However, a method of blending the aromatic thioether sulfone polymer and optional components as necessary and melt-kneading them, more specifically, a method of uniformly dry-blending with a tumbler, a Henschel mixer, etc. as necessary, and then charging into a twin-screw extruder and melt-kneading can be mentioned.

[0049] From the viewpoints of dispersibility and productivity, a twin-screw kneading extruder is preferable as the melt-kneader. For example, it is preferable to perform melt-kneading while appropriately adjusting the range of the discharge amount of the resin component of 5 to 500 (kg / hr) and the range of the screw rotation speed of 50 to 500 (rpm). It is more preferable to perform melt-kneading under the condition that the ratio (discharge amount / screw rotation speed) is in the range of 0.02 to 5 (kg / hr / rpm). In addition, the addition and mixing of each component to the melt-kneader may be performed simultaneously or separately. For example, when adding an additive among the above components, it is preferable from the viewpoint of dispersibility to charge it into the extruder from the side feeder of the twin-screw kneading extruder. The position of such a side feeder is preferably such that the ratio of the distance from the resin charging part (top feeder) of the twin-screw kneading extruder to the side feeder to the total length of the screw of the twin-screw kneading extruder is 0.1 or more, and more preferably 0.3 or more. Also, it is preferable that such a ratio is 0.9 or less, and more preferably 0.7 or less.

[0050] The aromatic thioether sulfone polymer composition according to the present embodiment obtained by melt-kneading in this way has a morphology in which the aromatic thioether sulfone polymer forms a continuous phase and other essential components and optional components are dispersed. The aromatic thioether sulfone polymer composition according to the present embodiment, after the melt-kneading, is processed into a form such as pellets, chips, granules, powders, etc. by a known method, for example, by extruding the polymer composition in a molten state into strands, and then it is preferably pre-dried in the temperature range of 100 to 150°C as necessary.

[0051] <Method for manufacturing a molded article> The manufacturing method of the molded article according to this embodiment includes a step of melt-molding the aromatic thioether sulfone polymer composition obtained by the manufacturing method of the aromatic thioether sulfone polymer composition according to this embodiment described above.

[0052] The molding of the aromatic thioether sulfone polymer composition can be used for various moldings such as injection molding, compression molding, composite, sheet, pipe extrusion molding, drawing molding, blow molding, transfer molding, etc. When molding by injection molding, various molding conditions are not particularly limited and can be molded by a generally common method.

[0053] The uses of the aromatic thioether sulfone polymer and polymer composition according to this embodiment are not particularly limited and can be used as various products. For example, it can be widely used as electrical and electronic components such as connectors, printed circuit boards, and encapsulated molded products, automotive parts such as lamp reflectors and various electrical equipment parts, interior materials for various buildings, aircraft, and automobiles, or precision parts such as OA equipment parts, camera parts, and watch parts. In particular, due to its excellent refractive index and transparency, it is suitable for various optical materials such as plastic lenses such as spectacle lenses, camera lenses, and prism lenses, hard coat agents, antireflection films, prism lenses, and LED encapsulation materials.

Examples

[0054] The present invention will be specifically described below with reference to examples. These examples are illustrative and not limiting.

[0055] <Evaluation>

[0056] (1) Measurement of oligomer content The polymers obtained in each example and comparative example were weighed into a 10.0000 g flask using an analytical balance. After extraction with acetone for 1 hour using a Soxhlet extractor, the oligomer amount of each sample was calculated from the residue amount obtained by drying the acetone solution in an oven at 50°C. The measurement results are shown in Table 1. (Weight of the remaining residue after drying)÷(Weight of the polymer used in extraction)×100

[0057] (2) Measurement of refractive index The polymers obtained in each example and comparative example were melt-molded into films with a thickness of 40 μm and used as test pieces. The refractive index at a wavelength of 589 nm was measured using a "prism coupler" manufactured by Metricon according to the method specified in JIS K 7142. The measurement results are shown in Table 1.

[0058] (3) Measurement of lightness (L * value) The polymers obtained in each example and comparative example were melt-molded into films with a thickness of 40 μm and used as test pieces. The lightness was measured using a colorimetric color difference meter "ZE 6000" manufactured by Nippon Denshoku Industries Co., Ltd. The measurement was carried out in accordance with JIS Z 8781-4, and the lightness (L * value) was measured by reflection measurement using a white plate as the background. The larger the value, the less coloring in the polymer. The measurement results are shown in Table 1.

[0059] (4) Measurement of transmittance The polymers obtained in each example and comparative example were melt-molded into films with a thickness of 40 μm and used as test pieces. The transmittance at 450 nm was measured using an ultraviolet-visible spectrophotometer "UV-3150" manufactured by Shimadzu Corporation. The measurement results are shown in Table 1.

[0060] (5) Measurement of the amount of generated gas The polymers obtained in each example and comparative example were weighed into an aluminum petri dish with a precision balance to 4.0000 g. After the sample was left standing in a dryer set at 150 °C for 1 hour, the petri dish was taken out, allowed to cool to room temperature, and then weighed. Next, the same petri dish was left standing in a dryer set at 370 °C for 1 hour, the petri dish was taken out, allowed to cool to room temperature, and then weighed. The weight loss of each sample was calculated from the following formula. The measurement results are shown in Table 1. {(Weight after heating at 150 °C) - (Weight after heating at 370 °C)}÷(Weight after heating at 150 °C)×100

[0061] (6) Evaluation of melt viscosity and melt stability Regarding the viscosity change rate of the polymers obtained in each example and comparative example, it was calculated from the values measured using a flow tester "CFT-500D" manufactured by Shimadzu Corporation, at a temperature of 300 °C, a load of 1.96 MPa, and an orifice with a ratio of orifice length to orifice diameter of 10 / 1, according to the following formula. The viscosity change rate is an absolute value. The measurement results are shown in Table 1. Viscosity change rate (%) = |(Melt viscosity Pa·s measured after holding for 30 minutes / Melt viscosity Pa·s measured after holding for 6 minutes)| × 100

[0062] <Example 1, Comparative Examples 1 and 2>

[0063] · Example 1 - Step (1) A 1 L autoclave made of titanium was charged with 4,4-dichlorodiphenyl sulfone (0.51 mol, 145.01 g), sodium acetate (0.50 mol, 41.02 g), diphenyl sulfone (2.00 mol, 436.54 g), deionized water (2.22 mol, 39.96 g), sodium sulfide (47.8%, 0.50 mol, 59.02 g), and sodium hydroxide (48.7%, 0.50 mol, 41.09 g), heated to 200 °C, and heated under sealed conditions at 200 °C for 3 hours.

[0064] · Example 1 - Step (2) After the polymerization was completed, the reaction solution was cooled to room temperature and solidified. The solidified crude reaction mixture was collected in a mixer ("Sample Mill" manufactured by Kyoritsu Riko Co., Ltd.) and crushed. The D of the crushed crude reaction mixture 50 was 40 μm.

[0065] · Example 1 - Step (3) The crushed crude reaction mixture was collected in a container, and washing with a mixed solvent of acetone and methanol (mass ratio 1:1) and washing with warm water (70 °C) were repeated 3 times. Then, the solid phase component recovered by filtration was dried at 120 °C for 2 hours under normal pressure, and then further dried at 150 °C for 5 hours under reduced pressure to obtain Polymer (1). The properties of the obtained polymer are shown in Table 1.

[0066] · Comparative Example 1 A 1 L titanium autoclave was charged with 4,4-dichlorodiphenyl sulfone (0.54 mol, 154.70 g), sodium carbonate (0.53 mol, 56.60 g), sodium acetate (0.53 mol, 43.70 g), sodium hydrosulfide (0.53 mol, 62.82 g), N-methyl-2-pyrrolidone (hereinafter referred to as NMP) (2.13 mol, 221.70 g), and deionized water (0.13 mol, 2.27 g), heated to 200 °C, and heated under seal at 200 °C for 3 hours. Subsequently, a mixed solvent of 160 mL of NMP and 26.7 mL of deionized water was injected, and stirring was continued until the temperature reached 150 °C. After the polymerization was completed, the reaction solution was cooled to room temperature and solidified. The solidified crude reaction mixture was taken out of the reaction vessel, and the liquid was removed by suction. The obtained crude reaction mixture was washed with hot deionized water (about 90 °C, about 600 mL) and filtered, and this operation was repeated twice. Subsequently, it was washed with deionized water at room temperature to remove water-soluble impurities. 40 g of the mixture purified and recovered as described above was separated and placed in a 1 L autoclave, 400 g of deionized water and 4.0 g of zinc acetate were added, heated to 185 °C, and heated and stirred for 1 hour for washing. After cooling to room temperature, it was further washed with hot water (about 90 °C, about 400 mL) while stirring. Subsequently, it was dried under reduced pressure at 160 °C to obtain a brown polymer. The properties of the obtained polymer are shown in Table 1.

[0067] · Comparative Example 2 To a 1 L titanium autoclave, sodium hydrosulfide (47.6%, 0.50 mol, 58.87 g), sodium hydroxide (48.8%, 0.45 mol, 36.89 g), sodium acetate anhydrous (0.25 mol, 20.51 g), sodium carbonate (0.06 mol, 6.36 g), and NMP (4.00 mol, 396.72 g) were added, and the mixture was heated at 130 °C for 3 hours under sealing. Then, it was cooled to 70 °C, NMP (0.50 mol, 49.59 g) and 4,4-dichlorodiphenyl sulfone (0.51 mol, 146.45 g) were added, and the mixture was heated at 260 °C for 2 hours. Then, the autoclave was gradually cooled to 120 °C at a rate of 1 °C / min. The obtained crude reaction mixture was recovered, N-methyl-2-pyrrolidone (1.5 mol, 148.77 g) was added, and then the mixture was filtered at 70 °C using a 200-mesh wire mesh. The obtained polymer was washed 5 times with 250 mL of warm water at 70 °C, and finally 5 mL of acetic acid was added. The properties of the polymer obtained by drying the solid component after filtration at 120 °C for 2 hours and at 150 °C for 5 hours are shown in Table 1.

[0068]

Table 1

[0069] From Table 1, it is recognized that the aromatic thioether sulfone polymer obtained by the production method of the example has a high refractive index, little coloring, and high transparency. Furthermore, since the amount of generated gas and the viscosity change rate are small, it was shown to be excellent in thermal stability.

Claims

1. A method for producing an aromatic thioether sulfone polymer, comprising polymerizing a dihaloaromatic compound with (i) an alkali metal sulfide or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in a water-containing sulfone-based solvent.

2. Step (1) of obtaining a crude reaction mixture by polymerizing a dihaloaromatic compound with (i) an alkali metal sulfide or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide in a water-containing sulfone-based solvent, Step (2) of crushing the crude reaction mixture, Step (3) of bringing the crushed crude reaction mixture into contact with a polar organic solvent and then performing solid-liquid separation to obtain a solid phase component (A), and The molar ratio of the dihaloaromatic compound in step (1) to (i) an alkali metal sulfide or (ii) an alkali metal hydrosulfide and an alkali metal hydroxide is 0.95 to 1.2, and The oligomer content of the solid phase component (A) is 3.5 parts by mass or less with respect to 100 parts by mass of the solid phase component (A). The method for producing an aromatic thioether sulfone polymer according to Claim 1, characterized by the above.

3. The method for producing an aromatic thioether sulfone polymer according to Claim 1 or 2, wherein the refractive index of the obtained polymer is 1.65 or more, the lightness is 85% or more, and the transmittance is 70% or more. (However, the lightness and transmittance are values measured for a film-like test piece having a thickness of 40 μm. Also, the lightness is a value of reflection measurement using a white plate as a background in accordance with JIS Z 8781-4, and the transmittance is a value measured at a wavelength of 450 nm.)

4. The method for producing an aromatic thioether sulfone polymer according to Claim 1 or 2, wherein the viscosity change rate of the obtained polymer is 0 to 10%. (However, the viscosity change rate is calculated from the following formula based on the value measured using an orifice having a ratio of orifice length to orifice diameter of 10 / 1 at a temperature of 300 ° C. and a load of 1.96 MPa using a flow tester.) Viscosity change rate [%] = |(Melt viscosity [Pa·s] measured after holding for 30 minutes / Melt viscosity [Pa·s] measured after holding for 6 minutes)| × 100

5. A method for producing an aromatic thioether sulfone polymer composition, comprising a step of blending an aromatic thioether sulfone polymer produced by the method according to Claim 1 or 2 with another substance and performing melt kneading.

6. A method for manufacturing a molded article, comprising a step of melt-molding an aromatic thioether sulfone polymer composition produced by the method according to claim 5.

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