Process for producing sulfur-containing polymer

Abstract

To provide a production method of a sulfur-containing polymer excellent in transmittance after heating.SOLUTION: A production method of a sulfur-containing polymer having a sulfoxide skeleton in the main chain includes an oxidation step for oxidize a sulfur-containing polymer having a sulfoxide skeleton in the main chain with at least one kind of compound selected from the group consisting of hypochlorous acid, a hypochlorite, and a compound capable of producing hypochlorous acid.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a method for producing a sulfur-containing polymer. More specifically, the present invention relates to a method for producing a sulfur-containing polymer, which includes an oxidation step of oxidizing using a specific compound.

Background Art

[0002] As high refractive index materials, polycarbonates having aromatic rings and polymer materials having fluorene skeletons are known. As refractive index adjustment materials for improving the light extraction efficiency of LEDs and lens materials for imaging systems, materials having a large Abbe number, that is, small light dispersion, are required. As such materials having a high refractive index and small light dispersion, materials into which sulfur molecules or halogen molecules are introduced, materials containing metal oxide nanoparticles, and the like have been developed.

[0003] As a material containing sulfur, for example, polyarylene sulfide is known. For example, a method for producing polyarylene sulfide by polymerizing diphenyl disulfide and / or thiophenol using a vanadium compound as an oxidative polymerization catalyst is known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] As a result of investigations by the present inventors, it has been found that polyarylene sulfide obtained by oxidative polymerization using a vanadium compound as an oxidative polymerization catalyst has a problem in transmittance after heating. Therefore, an object of the present invention is to provide a method for producing a sulfur-containing polymer having excellent transmittance after heating.

Means for Solving the Problems

[0006] As a result of the present inventors' detailed study on a method for oxidizing a sulfide group in a polyarylene sulfide to a sulfinyl group, it was found that when a specific compound was used, the transmittance of the resulting polymer after heating was improved, leading to the present invention. That is, the present invention is a method for producing a sulfur-containing polymer having a sulfoxide skeleton in the main chain, comprising an oxidation step of oxidizing a sulfur-containing polymer having a sulfide skeleton in the main chain using at least one compound selected from the group consisting of hypochlorous acid, hypochlorite, and a compound capable of generating hypochlorous acid, and is characterized by being a method for producing a sulfur-containing polymer.

Advantages of the Invention

[0007] The method for producing a sulfur-containing polymer of the present invention includes a step of oxidizing a sulfur-containing polymer having a sulfide skeleton in the main chain using a specific compound. Therefore, the sulfur-containing polymer obtained by the production method and having a sulfoxide skeleton in the main chain has excellent transmittance after heating. As a result, a material using the polymer has excellent transmittance after heating and is thus useful as an optical material such as a lens.

Embodiments for Carrying Out the Invention

[0008] Hereinafter, the present invention will be described in detail. Note that a combination of two or more of the individual preferred forms of the present invention described below is also a preferred form of the present invention. In addition, in this specification, “(meth)acrylate” means “acrylate” or “methacrylate”, “(meth)acrylic” means “acrylic” or “methacrylic”, and “(meth)acryloyl” means “acryloyl” or “methacryloyl”. Also, (meth)acrylate is sometimes referred to as (meth)acrylic acid ester.

[0009] 1. Method for Producing Sulfur-Containing Polymer The method for producing a sulfur-containing polymer of the present invention is a method for producing a sulfur-containing polymer having a sulfoxide skeleton in the main chain, and includes an oxidation step of oxidizing a sulfur-containing polymer having a sulfide skeleton in the main chain using at least one compound selected from the group consisting of hypochlorous acid, hypochlorite, and a compound capable of generating hypochlorous acid.

[0010] In the following description, the method for producing a sulfur-containing polymer of the present invention is also simply referred to as the production method of the present invention. In the present invention, having a sulfide skeleton in the main chain means having a structure containing at least one sulfide group (-S-) on the main chain of the polymer, and having a sulfoxide skeleton in the main chain means having a structure containing at least one sulfinyl group (-S(=O)-) on the main chain of the polymer.

[0011] The production method of the present invention includes an oxidation step of oxidizing a sulfur-containing polymer having a sulfide skeleton in the main chain. By the above oxidation step, at least a part of the sulfide skeleton in the sulfur-containing polymer having a sulfide skeleton in the main chain is oxidized to a sulfoxide skeleton, and a sulfur-containing polymer having a sulfoxide skeleton in the main chain is obtained. In the present invention, the sulfur-containing polymer having a sulfide skeleton in the main chain used in the oxidation step may also be referred to as a sulfide-containing polymer, and the sulfur-containing polymer having a sulfoxide skeleton in the main chain may also be referred to as a sulfoxide-containing polymer.

[0012] <Sulfide-containing polymer> The sulfur-containing polymer having a sulfide skeleton in the main chain, that is, the sulfide-containing polymer is preferably a sulfur-containing polymer having a structural unit (A) represented by the following general formula (1), for example.

[0013] [Chemical formula]

[0014] (In formula (1), X 1 represents a divalent aromatic hydrocarbon group which may have a substituent.) Examples of the divalent aromatic hydrocarbon group include a phenylene group, a naphthylene group, an anthrylene group, a triphenylene group, a biphenylene group, a phenanthrylene group, and the like. Among them, in terms of further reducing the light dispersion of the polymer, the divalent aromatic hydrocarbon group is preferably a phenylene group, a naphthylene group, an anthrylene group, a biphenylene group, or a triphenylene group, and more preferably a phenylene group.

[0015] Examples of the substituent that the divalent aromatic hydrocarbon group may have (also referred to as "substituent A") preferably include a reactive functional group, a halogen atom, or an alkyl group, an alkoxy group, an aryl group, an aralkyl group, or a sulfur-containing substituent that may have a substituent (also referred to as "substituent B").

[0016] Examples of the reactive functional group include acidic functional groups such as a carboxy group (-COOH), a phosphoric acid group (-OPO(OH)3), a hydroxy group (-OH), a sulfo group (-SO3H), a sulfuric acid group (-OSO3H), a phosphonic acid group (-PO(OH)3), a phosphinic acid group (-PO(OH)-), and a mercapto group (-SH); basic functional groups such as an amino group, an ammonium group, an imino group, an amide group, an imide group, a maleimide group, and a cyano group; curable functional groups such as a group having a reactive unsaturated bond (for example, a group having a reactive double bond such as a vinyl group, a (meth)acryloyl group, an allyl group, and a methallyl group), and a group having a reactive ionic bond (for example, a group having a reactive cyclic ether group such as an epoxy group and an oxetane group); and a group containing these functional groups.

[0017] Examples of the group containing these functional groups include groups having an acidic functional group, a basic functional group, or a curable functional group described above, and a hydrocarbon chain or a linking group, etc. That is, in the present invention, the reactive functional group includes not only the acidic functional group, the basic functional group, and the curable functional group described above, but also a group containing a linking chain with these functional groups. Examples of the linking chain include a divalent hydrocarbon group such as an alkylene group and an arylene group, a linking group such as an ether, an ester, a carbonyl, and an amide, and combinations thereof. For example, when a carboxy group is preferable as the reactive functional group, it means that the reactive functional group is preferably a carboxy group and / or a group containing a carboxy group.

[0018] The preferred form of the reactive functional group differs from the viewpoint of various physical properties in the sulfoxide-containing polymer obtained by the production method of the present invention. For example, from the viewpoint of improving the dispersibility of inorganic particles, an acidic functional group, a basic functional group, or a group containing these functional groups is preferable, and a carboxy group, a phosphoric acid group, a phosphonic acid group, a hydroxyl group, or a group containing these functional groups is more preferable. From the viewpoint of low linear expansion coefficient, a carboxy group, a phosphoric acid group, a phosphonic acid group, a hydroxyl group, or a group containing these functional groups is preferable, and a hydroxyl group or a group containing a hydroxyl group is more preferable. From the viewpoint of improving the adhesion to the substrate, a carboxy group, a phosphoric acid group, a phosphonic acid group, or a group containing these functional groups is preferable, and a phosphoric acid group, a phosphonic acid group, or a group containing these functional groups is more preferable. Examples of the substrate on which the adhesion can be improved include inorganic substrates such as an inorganic particle substrate (coating), a metal oxide particle substrate (coating), a glass substrate, a silicone substrate, and a copper substrate, and organic substrates such as an organic particle substrate (coating) and a polymer film substrate. From the viewpoint of improving heat resistance, mechanical strength, and solvent resistance, a carboxy group, a hydroxyl group, an amino group, a maleimide group, a curable functional group, or a group containing these functional groups is preferable, and a carboxy group, a hydroxyl group, an amino group, a maleimide group, a vinyl group, a (meth)acryloyl group, an allyl group, a methallyl group, an epoxy group, an oxetane group, or a group containing these functional groups is more preferable.

[0019] Among them, in terms of being able to provide a higher refractive index along with excellent physical properties, the reactive functional group is preferably a carboxy group, a phosphoric acid group, a phosphonic acid group, a hydroxyl group, a curable functional group, or a group containing these functional groups, more preferably a carboxy group, a phosphoric acid group, a hydroxyl group, a vinyl group, an epoxy group, or a group containing these functional groups, and still more preferably a phosphoric acid group, a hydroxyl group, a vinyl group, or a group containing these functional groups. Further, in addition to a high refractive index, in terms of being able to improve the adhesion to the base material with a low coefficient of linear expansion, the reactive functional group is preferably a carboxy group, a phosphoric acid group, or a group containing these functional groups.

[0020] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Among them, a bromine atom is preferable.

[0021] Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an s-butyl group, a t-butyl group, a pentyl group, an isopentyl group, a neopentyl group, a hexyl group, a 2-methylpentyl group, a 3-methylpentyl group, a 2,2-dimethylbutyl group, a 2,3-dimethylbutyl group, a heptyl group, etc. Among them, an alkyl group having 1 to 18 carbon atoms is preferable, an alkyl group having 1 to 6 carbon atoms is more preferable, and a methyl group is still more preferable.

[0022] Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an s-butoxy group, a t-butoxy group, a pentyloxy group, a phenoxy group, a cyclohexyloxy group, a benzyloxy group, etc. Among them, an alkoxy group having 1 to 18 carbon atoms is preferable, an alkoxy group having 1 to 6 carbon atoms is preferable, and a methoxy group is more preferable.

[0023] Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, a triphenyl group, etc. Among them, a phenyl group is preferable. The number of carbon atoms of the aryl group is preferably 6 to 30, more preferably 6 to 18, and still more preferably 6 to 12.

[0024] Examples of the above aralkyl group include benzyl group, phenethyl group, phenylpropyl group, phenylpentyl group, phenylhexyl group, phenyloctyl group and the like. The number of carbon atoms of the above aralkyl group is preferably 7 to 14, and more preferably 7 to 9.

[0025] Examples of the above sulfur-containing substituent include thioalkyl group, thioaryl group and the like. Among them, thioalkyl group is preferred. The number of carbon atoms of the above sulfur-containing substituent is preferably 1 to 8, more preferably 1 to 6, and still more preferably 1 to 4.

[0026] The above alkyl group, alkoxy group, aryl group, aralkyl group, and sulfur-containing substituent may further have a substituent (substituent B). Examples of the substituent (substituent B) include an alkyl group, a halogen atom, and a hydroxyl group. Among them, from the viewpoint of the solubility of the above polymer, an alkyl group is preferred, and from the viewpoint of the dispersibility of inorganic particles, a hydroxyl group is preferably mentioned.

[0027] Among them, from the viewpoint of further increasing the refractive index and Abbe number, as the substituent (substituent A) that the above divalent aromatic hydrocarbon group may have, the above alkyl group having 1 to 18 carbon atoms and sulfur-containing substituent are more preferred, methyl group and thioalkyl group are still more preferred, and methyl group is particularly preferred. Also, from the viewpoint of improving the dispersibility of inorganic particles, as the substituent that the above divalent aromatic hydrocarbon group may have, a hydroxyl group and a sulfur-containing substituent are more preferred, a hydroxyl group, thioalkyl group, and thioaryl group are still more preferred, and a hydroxyl group is particularly preferred.

[0028] The number of the substituent A that the above divalent aromatic hydrocarbon group may have is not particularly limited, but from the viewpoint of further increasing the refractive index of the polymer, a smaller number is preferred. Specifically, it is preferably 1 to 6, more preferably 1 to 3, and still more preferably 1.

[0029] In the above divalent aromatic hydrocarbon group, the position to which the substituent A binds is not particularly limited. The same applies when the divalent aromatic hydrocarbon group is a phenylene group, and even when the substituent A is, for example, an alkyl group, the binding position is not particularly limited. However, from the viewpoints of the solubility of the resulting sulfoxide-containing polymer in a solvent and light resistance, it is preferably bonded to the 4-position of the phenylene group.

[0030] The above structural unit (A) is preferably a structural unit (A-1) represented by the following general formula (1-1) in that the refractive index becomes higher.

[0031]

Chemical formula

[0032] (In the formula, R 1 represents, independently or differently, a reactive functional group, a halogen atom, or an alkyl group, an alkoxy group, an aryl group, an aralkyl group, or a sulfur-containing substituent which may have a substituent. a represents the number of R 1 and is an integer from 0 to 4.) R 1 When there are a plurality of them, they may be the same or different from each other.

[0033] R 1 The reactive functional group, halogen atom, or alkyl group, alkoxy group, aryl group, aralkyl group, or sulfur-containing substituent which may have a substituent represented by is preferably the same as the substituent which the divalent aromatic hydrocarbon group in the above general formula (1) may have. Among them, as R 1 , a methyl group and a thioalkyl group are more preferable, and a methyl group is particularly preferable. In the above general formula (1-1), a represents the number of the substituent R 1 and is an integer from 0 to 4. a is preferably 1 to 3, more preferably 1 or 2, and still more preferably 1 in that the refractive index becomes even higher.

[0034] In a preferred embodiment, the sulfide-containing polymer is a sulfur-containing polymer having the above structural unit (A), and is not further limited, but may further contain a structural unit (B) represented by the following general formula (2) and / or a structural unit (C) represented by the following general formula (3).

[0035]

Chemical formula

[0036]

Chemical formula

[0037] (In formulas (2) and (3), X 2 and X 3 each independently represent a divalent aromatic hydrocarbon group which may have a substituent.) In the structural unit (B) represented by the general formula (2), in the formula, X 2 represents a divalent aromatic hydrocarbon group which may have a substituent. Examples of the divalent aromatic hydrocarbon group represented by X 2 are preferably the same groups as those of the divalent aromatic hydrocarbon group represented by X 1 described above. Examples of the substituent which the divalent aromatic hydrocarbon group represented by X 2 may have are preferably the same groups as those of the substituent which the divalent aromatic hydrocarbon group represented by X 1 described above may have. The divalent aromatic hydrocarbon group represented by X 2 and its substituent may be the same as or different from the divalent aromatic hydrocarbon group represented by X 1 and its substituent.

[0038] The structural unit (B) is preferably a structural unit (B-1) represented by the following general formula (2-1) in terms of high polarity due to solubility and the like.

[0039]

Chemical formula

[0040] (In the formula, R 2 represents, independently or differently, a reactive functional group, a halogen atom, or an alkyl group, an alkoxy group, an aryl group, an aralkyl group, or a sulfur-containing substituent which may have a substituent. b represents the number of R 2 and is an integer from 0 to 4.) R 2 When there are a plurality of them, they may be the same or different from each other.

[0041] R 2 Examples of the reactive functional group, halogen atom, or alkyl group, alkoxy group, aryl group, aralkyl group, or sulfur-containing substituent which may have a substituent represented by are the same groups as those represented by the above-mentioned R 1 . Among them, in terms of further increasing the refractive index, as the above R 2 , a methyl group and a thioalkyl group are more preferable, and a methyl group is particularly preferable. In the general formula (2-1), b represents the number of the substituent R 2 and is an integer from 0 to 4. b is preferably 1 to 3, more preferably 1 or 2, and still more preferably 1 in terms of further increasing the refractive index.

[0042] In the structural unit (C) represented by the general formula (3), in the formula, X 3 represents a divalent aromatic hydrocarbon group which may have a substituent. Examples of the divalent aromatic hydrocarbon group represented by X 3 are preferably the same groups as the divalent aromatic hydrocarbon group represented by the above-mentioned X 1 . Examples of the substituent which the divalent aromatic hydrocarbon group represented by X 3 may have are preferably the same groups as the substituent which the divalent aromatic hydrocarbon group represented by the above-mentioned X 1 may have. The divalent aromatic hydrocarbon group represented by X 3 and its substituent are X 1 or X 2It may be the same as or different from the divalent aromatic hydrocarbon group represented by and its substituent.

[0043] In terms of high transparency, the above structural unit (C) is preferably a structural unit (C-1) represented by the following general formula (3-1).

[0044] [Chemical formula]

[0045] (In the formula, R 3 represents, independently or identically, a reactive functional group, a halogen atom, or an alkyl group, an alkoxy group, an aryl group, an aralkyl group, or a sulfur-containing substituent which may have a substituent. c represents the number of R 3 and is an integer from 0 to 4.) R 3 When there are a plurality of R 3 they may be the same or different from each other. Examples of the reactive functional group, halogen atom, or alkyl group, alkoxy group, aryl group, aralkyl group, or sulfur-containing substituent which may have a substituent represented by R 1 are the same groups as those represented by the above-mentioned R 3 respectively. Among them, in terms of further increasing the refractive index, as the above R 3 , a methyl group and a thioalkyl group are more preferable, and a methyl group is particularly preferable. In the above general formula (3-1), c represents the number of the substituent R 3 and is an integer from 0 to 4. c is preferably 1 to 3, more preferably 1 or 2, and still more preferably 1 in terms of further increasing the refractive index.

[0046] The above sulfide-containing polymer may be a polymer containing only the above structural unit (A), or may be a copolymer containing structural unit (A) and structural unit (B) and / or structural unit (C). When it is the above copolymer, its form is not particularly limited. For example, it may be an alternating copolymer, a block copolymer, or a random copolymer. The above sulfide-containing polymer may have one or more of the above structural units (A), (B), or (C).

[0047] In the above sulfide-containing polymer, the content ratio of the above structural unit (A) is preferably 50 to 100 mol%, more preferably 80 to 100 mol%, and still more preferably 95 to 100 mol% with respect to 100 mol% of all the structural units of the polymer. The total content ratio of the above structural unit (B) and structural unit (C) is preferably 0 to 50 mol%, more preferably 0 to 20 mol%, and still more preferably 0 to 5 mol% with respect to 100 mol% of all the structural units.

[0048] In the above sulfide-containing polymer, the total content ratio of the above structural units (A), (B), and (C) is preferably 50 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, even more preferably 95 mol% or more, and particularly preferably 100 mol% with respect to 100 mol% of all the structural units of the polymer.

[0049] The above sulfide-containing polymer may have another structural unit (D) other than the above structural units (A), (B), and (C). Examples of the above structural unit (D) include structural units having at least the above-described reactive functional groups.

[0050] Examples of the monomer capable of introducing the above structural unit (D) include monomers having a polymerizable double bond and the above reactive functional group. Examples of the polymerizable double bond include a vinyl group, a (meth)acryloyl group, an allyl group, a methallyl group, etc. Among them, a (meth)acryloyl group is preferable. Examples of the monomer having a polymerizable double bond and the above reactive functional group include carboxy group-containing (meth)acrylates such as 2-carboxyethyl (meth)acrylate, 2-carboxypropyl (meth)acrylate, 3-carboxypropyl (meth)acrylate, 4-carboxybutyl (meth)acrylate; phosphate group-containing (meth)acrylates such as 2-(meth)acryloyloxyethyl acid phosphate; epoxy group-containing (meth)acrylates such as glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate; vinyl ether group-containing (meth)acrylates such as 2-(2-vinyloxyethoxy)ethyl (meth)acrylate, etc.

[0051] The content ratio of the above structural unit (D) is preferably 0 to 50 mol%, more preferably 0 to 20 mol%, and still more preferably 0 to 5 mol% with respect to 100 mol% of all the structural units of the polymer.

[0052] The above sulfide-containing polymer preferably has the above reactive functional group at the main chain terminal and / or side chain. By having the above reactive functional group at least at the main chain terminal or side chain, the sulfoxide-containing polymer obtained after the oxidation reaction can exhibit excellent physical properties due to the above reactive functional group. The case where the reactive functional group is present in the side chain includes not only the case where the reactive functional group is present in the side chain of the above sulfide-containing polymer, but also the case where the substituent in the structural units (A) to (C) represented by the above general formulas (1) to (3) is the above reactive functional group or a group containing the above reactive functional group.

[0053] The weight average molecular weight (Mw) of the above sulfide-containing polymer is not particularly limited, but is preferably 500 to 10,000,000. When the weight average molecular weight is within the above range, the sulfoxide-containing polymer obtained by the production method of the present invention can be suitably used as an optical material. The above weight average molecular weight is more preferably 1,000 or more, still more preferably 3,000 or more, still more preferably 10,000 or more. On the other hand, it is more preferably 1,000,000 or less, still more preferably 100,000 or less.

[0054] The dispersity (weight average molecular weight / number average molecular weight) of the above sulfide-containing polymer is preferably 1 or more and 10 or less. When the dispersity is within the above range, the moldability of the sulfoxide-containing polymer obtained by the production method of the present invention is good. In terms of further improving the moldability, the dispersity is more preferably 5 or less, still more preferably 3 or less.

[0055] The above weight average molecular weight and number average molecular weight can be determined by measurement by gel permeation chromatography (GPC) method, specifically, by the method described in the examples below. The dispersity can be determined by dividing the weight average molecular weight by the number average molecular weight.

[0056] The above sulfide-containing polymer preferably has a glass transition temperature (Tg) of 80 to 250°C. When the glass transition temperature is within the above range, the molding process of the sulfoxide-containing polymer obtained by the production method of the present invention can be easily performed. From the viewpoint of increasing the heat resistance of the sulfoxide-containing polymer obtained by the production method of the present invention, the above glass transition temperature is more preferably 90°C or higher, still more preferably 100°C or higher. From the viewpoint of easily performing the molding process, it is more preferably 200°C or lower.

[0057] The glass transition temperature can be determined by a method of evaluation based on the intersection point of the baseline and the tangent line at the inflection point from a DSC curve obtained by heating from room temperature to 250 °C (heating rate: 10 °C / min) in a nitrogen gas atmosphere using a differential scanning calorimeter (DSC).

[0058] <Compound> In the above oxidation step, at least one compound selected from the group consisting of hypochlorous acid, hypochlorites, and compounds capable of generating hypochlorous acid is used. At least one compound selected from the group consisting of hypochlorous acid, hypochlorites, and compounds capable of generating hypochlorous acid is also collectively referred to as compound (Z).

[0059] The above hypochlorite is not particularly limited, but alkali metal salts such as potassium hypochlorite and sodium hypochlorite; alkaline earth metal salts such as calcium hypochlorite are preferred.

[0060] Examples of the compound capable of generating hypochlorous acid include trichloroisocyanuric acid (TCCA), trichloroisocyanurate salts such as sodium trichloroisocyanurate, N-chlorosuccinimide, N-chlorophthalimide, alkali metal salts such as sodium hypochlorite, alkaline earth metal salts such as calcium hypochlorite, chlorous acid, alkali metal salts such as sodium chlorite, alkaline earth metal salts such as calcium chlorite, chlorine dioxide, chlorine, etc. Among them, trichloroisocyanuric acid (TCCA) is preferred. Only one kind of the above compound (Z) may be used, or two or more kinds may be used in combination. Among the above compound (Z), hypochlorous acid, hypochlorite, or trichloroisocyanuric acid (TCCA) is more preferred, and trichloroisocyanuric acid (TCCA) is even more preferred.

[0061] <Oxidation reaction> The oxidation reaction in the above oxidation step is preferably carried out in a solvent. The solvent used in the oxidation reaction is also referred to as the oxidation reaction solvent. Examples of the oxidation reaction solvent include, for example, chlorinated hydrocarbons such as chloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, tetrachloroethylene, 1,1,2,2-tetrachloroethane, chlorobenzene, 1,2-dichlorobenzene, 1,3-dichlorobenzene; ethers such as tetrahydrofuran, diethyl ether, cyclopentyl methyl ether; amide solvents such as N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide; organic solvents such as esters such as ethyl acetate, and water. One or more of these can be used. Among these, ethers are more preferable, and tetrahydrofuran is even more preferable.

[0062] On the other hand, the oxidation reaction is preferably carried out in the coexistence of water. The presence of water promotes the oxidation reaction, and the oxidation reaction can be completed in a short time even at low temperatures. Therefore, the oxidation reaction solvent is preferably a mixed solvent of an organic solvent and water. The water content is not particularly limited, but the water content is preferably 1 to 30% by mass based on 100% by mass of the total amount of the oxidation reaction solvent (mixed solvent). More preferably, it is 2% by mass or more, even more preferably 5% by mass or more, more preferably 20% by mass or less, and even more preferably 15% by mass or less.

[0063] In the above oxidation step, it is preferable to mix the compound (Z) with the sulfide-containing polymer. When mixing, the compound (Z) may be used in its original form or in a form dissolved or dispersed in a solvent.

[0064] For example, when using hypochlorous acid or a hypochlorite as the compound (Z), it is preferably used as an aqueous solution containing these. As the aqueous solution of hypochlorous acid (salt), hypochlorous acid water mainly composed of hypochlorous acid obtained by electrolyzing an aqueous sodium chloride solution, hydrochloric acid water, or a mixed solution of hydrochloric acid and sodium chloride can also be used.

[0065] Also, regarding the compound capable of generating the above hypochlorous acid, when mixing with the sulfide-containing polymer, the compound may be used as it is, or a solution or dispersion in which the compound is dissolved or dispersed in a solvent may be used.

[0066] When mixing with the above compound (Z), it is preferable that the sulfide-containing polymer is previously in a state of being dispersed or dissolved in a solvent. That is, it is preferable to mix a solution or dispersion in which the above sulfide-containing polymer is dissolved or dispersed in a solvent with the above compound (Z). As the solvent, the same solvent as the oxidation reaction solvent used in the above oxidation reaction can be used.

[0067] In the above dispersion, the average particle diameter of the sulfide-containing polymer is preferably 100 μm or less in terms of easily obtaining a sulfoxide-containing polymer with a uniform degree of oxidation. The above average particle diameter is more preferably 10 μm or less, and even more preferably 1 μm or less. The upper limit is not particularly limited, but is preferably 0.001 μm or more, and more preferably 0.01 μm or more. The above average particle diameter is the 50% particle diameter in the volume-based particle size distribution and can be measured by the dynamic light scattering method or the static light scattering method.

[0068] When water is contained in the above oxidation reaction solvent, the sulfide-containing polymer may be added and mixed with a mixed solvent of an organic solvent and water to disperse or dissolve the sulfide-containing polymer in the mixed solvent, or the sulfide-containing polymer may be added and mixed with an organic solvent to disperse or dissolve it, and then water may be added.

[0069] The concentration of the sulfide-containing polymer in the above solution is not particularly limited, but the content of the sulfide-containing polymer with respect to 100% by mass of the above solution is preferably 0.01 to 99.9% by mass, more preferably 0.1 to 80% by mass, and even more preferably 1 to 50% by mass. The same applies to the concentration of the sulfide-containing polymer in the above dispersion.

[0070] The mixing ratio of the above compound (Z) to the above sulfide-containing polymer is not particularly limited, but is usually preferably 0.01 to 100 moles, more preferably 0.1 to 10 moles, and even more preferably 0.1 to 3 moles, expressed as the amount (moles) of compound (Z) per mole of sulfur atom in the sulfide-containing polymer.

[0071] Also, hypochlorous acid generated from the above compound (Z) is preferably 0.01 to 100 moles, more preferably 0.1 to 10 moles, and even more preferably 0.1 to 3 moles, expressed as the amount (moles) of hypochlorous acid generated from compound (Z) per mole of sulfur atom in the sulfide-containing polymer.

[0072] The reaction temperature of the above oxidation reaction is not particularly limited as long as the desired oxidation reaction proceeds, but from the viewpoint of facilitating the progress of the above oxidation reaction, it is preferably -20 to 200 °C, more preferably 0 °C or higher, even more preferably 5 °C or higher. Also, from the viewpoint of suppressing side reactions, it is more preferably 100 °C or lower, even more preferably 50 °C or lower. The reaction time of the above oxidation reaction is not particularly limited, but is usually 0.1 to 100 hours, preferably 0.5 to 20 hours, more preferably 1 hour or more. Also, from the viewpoint of excellent productivity, it is more preferably 10 hours or less, even more preferably 5 hours or less.

[0073] When oxidizing a part of the sulfide group (-S-) in the sulfide-containing polymer to a sulfonyl group (-SO2-), the reaction may be carried out for a longer time than the above-mentioned reaction time. Also, the amount of compound (Z) used in this case is not particularly limited as long as the desired oxidation reaction of sulfur atoms proceeds, but is usually preferably 1.5 to 100 moles, more preferably 2 to 50 moles, and even more preferably 2 to 10 moles, per mole of sulfur atom in the sulfide-containing polymer.

[0074] Since the sulfoxide-containing polymer obtained by the above oxidation step may contain residues of an acid or the like, it is preferably washed. The washing method is not particularly limited, and examples thereof include washing with water, an acid, a base, or the like. Further, in order to remove unreacted substances, the polymer may be passed through a filter or washed with a solvent. The solvent is not particularly limited, but the same solvent as the reaction solvent can be used.

[0075] In the above oxidation step, using the above compound (Z) as an oxidizing agent is also one of the preferred embodiments in the production method of the present invention. In addition, in the above oxidation step, an oxidizing agent other than the compound (Z) can also be used. The oxidizing agent is not particularly limited as long as it is a substance having oxidizing properties, but nitric acid, dinitrogen tetroxide, nitrogen dioxide, sulfuric acid, hydrogen peroxide, ozone, or a mixture thereof is preferably exemplified, and one or more of them can be appropriately selected and used.

[0076] When using an oxidizing agent other than the above compound (Z), its usage amount is preferably in a range that does not impair the effects of the present invention. For example, the total amount of the oxidizing agent other than the compound (Z) is preferably 0 to 20% by mass, more preferably 0 to 5% by mass, and still more preferably 0 to 1% by mass with respect to 100% by mass of the usage amount of the compound (Z) in the above oxidation step. Also, when it is desired to exhibit the effect of using an oxidizing agent other than the compound (Z), the total amount of the oxidizing agent other than the compound (Z) may exceed 20% by mass with respect to 100% by mass of the usage amount of the compound (Z).

[0077] <Polymer terminal control step> The production method of the present invention preferably further includes a terminal control step of performing a reaction for controlling the polymer terminal. The sulfoxide-containing polymer obtained by the above oxidation step has a terminal, for example, a sulfonyl chloride structure (-S(=O)2-Cl). By chemically modifying or modifying the structure of the terminal, the solubility and permeability can be improved, or a new function can be imparted to the terminal. Controlling the polymer end means controlling the end of the sulfoxide-containing polymer obtained in the above oxidation reaction to an arbitrary structure. The reaction for controlling the polymer end is sometimes referred to as an end control reaction.

[0078] The above end control step may be carried out on the above sulfide-containing polymer, on the above sulfoxide-containing polymer, or during the above oxidation step. That is, it may be carried out before the above oxidation step, after the above oxidation step, or simultaneously with the above oxidation step.

[0079] Among them, it is preferable to carry out the above polymer end control step after the above oxidation step or simultaneously with the above oxidation step, and it is preferable to start the end control reaction in the polymer end control step after the oxidation reaction in the above oxidation step has started. That is, it is preferable to start the above oxidation reaction first, and then carry out the end control reaction after the above oxidation reaction is completed or after the above oxidation reaction has proceeded to a certain extent. The above end control reaction is preferably carried out in a solvent. As the solvent, the same solvent as the above oxidation reaction solvent can be used.

[0080] The above end control step is preferably a step using a reducing substance. By using a reducing substance, for example, at least one end of the sulfoxide-containing polymer can be controlled to a structure having a thiol group. Furthermore, by making the end a thiol group, it can be modified with a compound containing an ethylenically unsaturated double bond and various functional groups can be introduced.

[0081] The reducing agent is not particularly limited, and examples thereof include metal or metalloid hydrides and their complex compounds (art complexes) such as sodium hydride, sodium borohydride, lithium aluminum hydride, butyllithium, diborane, sodium cyanoborohydride, lithium triethylborohydride, lithium tri(sec-butyl)borohydride, potassium tri(sec-butyl)borohydride, diisobutylaluminum hydride, sodium bis(2-methoxyethoxy)aluminum hydride, tributyltin hydride, lithium hexamethyldisilazide, and lithium diisopropylamide; metals such as metallic tin and metallic zinc; low-valent metal ion-containing compounds such as divalent iron ions and divalent tin ions; acid-based organic compounds such as formic acid and oxalic acid; phosphine-based organic compounds such as triphenylphosphine; and inorganic compounds such as hydrazine. One or more of these can be used. Among these, metals are preferred, and zinc is more preferred. When zinc is used, even if heavy metals used as catalysts or the like remain in the process of producing a sulfoxide-containing polymer, for example, in the process of producing a sulfide-containing polymer, the heavy metals can be removed, and a sulfoxide-containing polymer with suppressed coloring can be easily obtained. When a metal is used as the reducing agent, its form is not particularly limited, but it is preferably in the form of fine particles.

[0082] The end-capping reaction using the above reducing agent is preferably carried out in the presence of an acid. By carrying out the reaction in the presence of an acid, the end-capping reaction of the terminal structure to thiol can be promoted. This effect is particularly remarkable when a metal is used as the reducing agent, especially when zinc is used. Examples of the acid include hydrohalic acids such as hydrochloric acid, hydrobromic acid, hydroiodic acid, and hydrofluoric acid, inorganic acids such as sulfuric acid and nitric acid; carboxylic acids such as formic acid, acetic acid, propionic acid, lauric acid, stearic acid, and benzoic acid; and sulfonic acids such as p-toluenesulfonic acid. Among them, hydrochloric acid is preferred.

[0083] The amount of the reducing substance used is not particularly limited, but it is preferably 0.01 to 1000% by mass based on 100% by mass of the sulfide-containing polymer. More preferably, it is 0.1% by mass or more, still more preferably 5% by mass or more, and also more preferably 100% by mass or less, still more preferably 50% by mass or less.

[0084] The amount of the acid used is not particularly limited, but it is preferably 0.01 to 5000% by mass based on 100% by mass of the sulfide-containing polymer. More preferably, it is 0.5% by mass or more, still more preferably 10% by mass or more, and also more preferably 500% by mass or less, still more preferably 100% by mass or less.

[0085] By the terminal control reaction using a reducing substance, for example, a sulfoxide-containing polymer having a thiol group at the polymer terminal can be obtained, and the polymer can, for example, undergo an enethiol reaction with a compound containing an ethylenically unsaturated double bond. By this reaction, a sulfoxide-containing polymer into which the functional group of the compound is introduced can be obtained.

[0086] The compound containing an ethylenically unsaturated double bond is not particularly limited, and preferably includes (meth)acrylic monomers such as (meth)acrylic acid and (meth)acrylic acid esters; vinyl monomers such as vinyl acetate, vinyl chloride, and vinylidene fluoride; allyl monomers such as allyl acetate, allyl chloride, allyl alcohol, allyl ether, and allyl cyanide; olefin monomers such as ethylene, propylene, pentene, hexene, cycloheptene, cyclohexene, 2-norbornene, and 2-cyclohexene-1-one; and styrene monomers such as styrene and divinylbenzene. One or more of these can be used. Among them, (meth)acrylic monomers are preferable in terms of excellent industrial availability of compounds having various functional groups.

[0087] For example, by using (meth)acrylic acid as the compound containing an ethylenically unsaturated double bond, a carboxy group can be introduced to the polymer terminal. By using an alkyl (meth)acrylate, an alkyl group can be introduced to the polymer terminal. By using a polyfunctional alkyl (meth)acrylate, an ethylenically unsaturated double bond ((meth)acryloyl group) can be introduced to the polymer terminal.

[0088] The above terminal control step is also preferably a step of using ammonia, a primary amine or a secondary amine. By using ammonia, a primary amine or a secondary amine, at least one terminal of the sulfoxide-containing polymer can be controlled to "-S(=O)2-R". Here, R is NH2 when ammonia is used, and is an amine residue in which hydrogen of the amino group in the used amine has been eliminated when an amine is used.

[0089] In the above terminal control step, it is also preferable to coexist a basic substance. That is, in the above terminal control step, it is preferable to react ammonia, a primary amine or a secondary amine with the sulfoxide-containing polymer in the presence of a basic substance.

[0090] The above basic substance is not particularly limited. For example, it may be ammonia, a primary amine or a secondary amine, or it may be a basic substance other than these. For example, ammonia, a primary amine or a secondary amine in an amount exceeding the equivalent for modifying the terminal can also be used as the basic substance. However, for the reason that side reactions can be suppressed, substances other than ammonia, primary amines or secondary amines are preferred as the basic substance. For example, tertiary amines, alkali metal hydroxides, alkali metal carbonates, etc. are preferred. Preferred examples of the tertiary amine include aliphatic tertiary amines such as triethylamine, tributylamine, diisopropylethylamine, and aromatic amines such as pyridine and dimethylaminopyridine. Preferred examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, cesium hydroxide, etc. Preferred examples of the alkali metal carbonate include lithium carbonate, sodium carbonate, potassium carbonate, cesium carbonate, lithium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, cesium hydrogen carbonate, etc.

[0091] <Polymerization step> The production method of the present invention preferably includes a polymerization step of polymerizing a monomer component containing a sulfur-containing monomer to obtain a sulfur-containing polymer (sulfide-containing polymer) having a sulfide skeleton in the main chain. That is, as the sulfide-containing polymer used in the above oxidation step in the production method of the present invention, it is preferable to use a sulfide-containing polymer obtained by polymerizing a monomer component containing a sulfur-containing monomer. The above polymerization step is usually preferably carried out before the above oxidation step.

[0092] The above sulfur-containing monomer is not particularly limited as long as it can polymerize to give a sulfur-containing polymer having a sulfide skeleton in the main chain as described above, but disulfide compounds and thiol compounds are preferably mentioned, and more preferably, diaryl disulfide compounds represented by the following general formula (4) and thioaryl compounds represented by the following general formula (5) are mentioned.

[0093]

Chemical formula

[0094] [Chemical formula]

[0095] (In formulas (4) and (5), A 1 and A 2 each independently represent a monovalent aromatic hydrocarbon group which may have a substituent.) A 1 and A 2 The monovalent aromatic hydrocarbon group represented by the above is a monovalent aromatic hydrocarbon group obtained by making the divalent aromatic hydrocarbon group represented by X 1 in the general formula (1) monovalent, and examples thereof include a phenyl group, a naphthyl group, an anthryl group, a triphenyl group, a biphenyl group, a phenanthryl group, etc. Among them, a phenyl group, a naphthyl group, an anthryl group, a biphenyl group, or a triphenyl group is preferable, and a phenyl group is more preferable.

[0096] A 1 and A 2 The substituent and the number thereof that the monovalent aromatic hydrocarbon group represented by may have are the same as those of the substituent that the divalent aromatic hydrocarbon group represented by X 1 in the general formula (1) may have.

[0097] The above diaryl disulfide compound is preferably a compound represented by the following general formula (4-1). The above thioaryl compound is preferably a compound represented by the following general formula (5-1).

[0098] [Chemical formula]

[0099] [Chemical formula]

[0100] (In formulas (4-1) and (5-1), R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 and R 11 are the same or different and each represents a hydrogen atom, a halogen atom, a reactive functional group, or an alkyl group, an alkoxy group, an aryl group, an aralkyl group, or a sulfur-containing substituent which may have a substituent.) The above halogen atom, reactive functional group, or alkyl group, alkoxy group, aryl group, aralkyl group, or sulfur-containing substituent which may have a substituent is each the same as each group represented by R 1 in the general formula (1-1) described above. Further, examples of the substituent which these groups may have include the same substituents as the above-described substituent B, and among them, an alkyl group, a halogen atom, and a hydroxyl group are preferable.)

[0101] Specific examples of the diphenyl sulfide compound include, for example, 3,3'-dimethyl diphenyl disulfide, 2,2'-dimethyl diphenyl disulfide, 2,2',3,3'-tetramethyl diphenyl disulfide, 2,2',5,5'-tetramethyl diphenyl disulfide, 2,2',6,6'-tetramethyl diphenyl disulfide, 3,3',5,5'-tetramethyl diphenyl disulfide, 2,2',3,3',5,5'-hexamethyl diphenyl disulfide, 2,2',3,3',6,6'-hexamethyl diphenyl disulfide, 2,2',3,3',5,5',6,6'-octamethyl diphenyl disulfide, 2,2'-diethyl diphenyl disulfide, 3,3'-diethyl diphenyl disulfide, 2,2',6,6'-tetraethyl diphenyl disulfide, 2,2',3,3'-tetraethyl diphenyl disulfide, 2,2',5,5'-tetraethyl diphenyl disulfide, 3,3',5,5'-tetraethyl diphenyl disulfide, 2,2',3,3',5,5'-hexaethyl diphenyl disulfide, 2,2',3,3',6,6'-hexaethyl diphenyl disulfide, 2,2',3,3',5,5',6,6'-octaethyl diphenyl disulfide, 2,2'-dipropyl diphenyl disulfide, 3,3'-dipropyl diphenyl disulfide, 2,2',6,6'-tetrapropyl diphenyl disulfide, 2,2',3,3'-tetrapropyl diphenyl disulfide, 2,2',5,5'-tetrapropyl diphenyl disulfide, 3,3',5,5'-tetrapropyl diphenyl disulfide, 2,2',3,3',5,5'-hexapropyl diphenyl disulfide, 2,2',3,3',6,6'-hexapropyl diphenyl disulfide, 2,2',3,3',5,5',6,6'-octapropyl diphenyl disulfide, 2,2'-diisopropyl diphenyl disulfide, 3,3'-diisopropyl diphenyl disulfide, 2,2',6,6'-tetraisopropyl diphenyl disulfide, 2,2',3,3'-tetraisopropyl diphenyl disulfide, 2,2',5,5'-tetraisopropyl diphenyl disulfide, 3,3',5,5'-tetraisopropyl diphenyl disulfide, 2,2',3,3',5,Examples include 5'-hexaisopropyldiphenyldisulfide, 2,2',3,3',6,6'-hexaisopropyldiphenyldisulfide, 2,2',3,3',5,5',6,6'-octaisopropyldiphenyldisulfide, etc.

[0102] Specific examples of the thiol compound include, for example, 3-methylbenzenethiol, 2-methylbenzenethiol, thiophenol (benzenethiol), 2,3-dimethylbenzenethiol, 2,5-dimethylbenzenethiol, 2,6-dimethylbenzenethiol, 3,5-dimethylbenzenethiol, etc.

[0103] The above disulfide compound can also be prepared by oxidizing the thiol compound. Therefore, in the above polymerization step, a thiol compound can also be used as a precursor of the disulfide compound. A disulfide compound can be obtained by oxidatively bonding two molecules of the thiol compound. The method for the oxidative bonding is not particularly limited, and a known method can be used.

[0104] The above polymerization is preferably oxidative polymerization. The oxidative polymerization is not particularly limited, and oxidative polymerization using a quinone-based compound, oxidative polymerization using a catalyst, etc. can be used. In the production method of the present invention, from the viewpoint of reducing the amount of waste liquid, oxidative polymerization using a catalyst is preferred. Even when oxidative polymerization using a quinone-based compound is carried out, or when oxidative polymerization using a catalyst is carried out, the resulting sulfide-containing polymer is subjected to the production method of the present invention described above, and the resulting sulfoxide-containing polymer has excellent transmittance after heating.

[0105] For example, when oxidative polymerization is carried out using a quinone compound as a raw material with a monomer composition containing a diaryl disulfide compound represented by the above general formula (4) or a thioaryl compound represented by the above general formula (5), the resulting sulfide-containing polymer has a problem with the transmittance after heating. Although the cause is not clear, the sulfide-containing polymer obtained by oxidative polymerization using the above quinone compound has a disulfide bond at its terminal, and it is considered that the disulfide bond generates radicals upon heating, causing the coloring of the polymer. However, when the above sulfide-containing polymer is subjected to the production method (the above oxidation step) of the present invention described above, the resulting sulfoxide-containing polymer has excellent transmittance after heating. It is considered that this is because the structure at the terminal of the polymer has changed due to the above oxidation step.

[0106] Also, when oxidative polymerization is carried out using a catalyst with a monomer composition containing a diaryl disulfide compound represented by the above general formula (4) or a thioaryl compound represented by the above general formula (5) as a raw material, although there are differences depending on the composition of the catalyst used, the resulting sulfide-containing polymer has a problem with the transmittance after heating. The same is true even when purified by methods such as reprecipitation and filtration. Although the cause is not clear, the sulfide-containing polymer obtained by oxidative polymerization using a catalyst has a disulfide bond at its terminal, and it is considered that a metal component derived from the catalyst is strongly bonded (coordinated) to the disulfide bond, making it likely to contribute to coloring upon heating.

[0107] However, when the above sulfide-containing polymer is subjected to the production method (the above oxidation step) of the present invention described above, the resulting sulfoxide-containing polymer has excellent transmittance after heating. It is considered that the structure at the terminal of the polymer has changed due to the above oxidation step, and although it is not certain, it may be because the metal component derived from the catalyst has become free from the sulfoxide-containing polymer or has changed into a form that is less likely to contribute to coloring upon heating.

[0108] The oxidative polymerization using a quinone compound will be described. The quinone compounds that can be used in the oxidative polymerization using a quinone compound are not particularly limited. For example, 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), 2,3,5,6-tetrachloro-p-benzoquinone, 2,3,5,6-tetrabromo-benzoquinone, 2,3,5,6-tetrafluoro-p-benzoquinone, anthraquinone, 1,4-naphthoquinone, 2,3-dichloro-1,4-naphthoquinone, 2,3-dibromo-1,4-naphthoquinone, 2,3-dicyano-1,4-naphthoquinone, 3,4,5,6-tetrachloro-ortho-benzoquinone, 3,4,5,6-tetrabromo-ortho-benzoquinone, 3,4,5,6-tetrafluoro-benzoquinone, etc. can be mentioned. Among them, DDQ is preferable in terms of its high oxidizing power and easy availability. The above quinone compounds may be used alone or in combination of two or more.

[0109] In addition, when using the above quinone compound, it is also preferable to further use an acid. When the acid is used in combination with the quinone compound, the oxidizing power of the quinone compound can be maintained. The above acid is not particularly limited. For example, sulfuric acid, acetic acid, methanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, trifluoromethanesulfonic acid, 1,1,2,2-tetrafluoroethanesulfonic acid, trifluoroacetic acid, perfluoropropionic acid, perfluorobutyric acid, etc. can be mentioned. Among them, 1,1,2,2-tetrafluoroethanesulfonic acid is preferable in terms of increasing the acidity. The above acid may be used alone or in combination of two or more.

[0110] When the above quinone compound and acid are used in combination, the addition amount of the acid is preferably 10 to 1000 moles, more preferably 50 to 500 moles, and even more preferably 80 to 120 moles, based on 100 moles of the total amount of the above quinone compound to be added. The addition amount of the above quinone compound is preferably 0.1 to 3 moles, more preferably 0.8 to 1.5 moles, and even more preferably 0.9 to 1.1 moles, based on 1 mole of the monomer component to be used.

[0111] In the above polymerization step, the polymerization temperature is not particularly limited as long as it is a temperature at which oxidative polymerization proceeds. However, in terms of facilitating the progress of oxidative polymerization, it is preferably 0 to 200 °C, more preferably 10 °C or higher, still more preferably 15 °C or higher. Also, in terms of suppressing side reactions, it is more preferably 180 °C or lower, still more preferably 150 °C or lower. The polymerization time is not particularly limited, but is usually 0.1 to 100 hours, preferably 1 to 80 hours, more preferably 5 to 50 hours, and still more preferably 10 to 24 hours.

[0112] In the above polymerization, a solvent may be used. Preferred solvents include, for example, dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, tetrachloroethylene, 1,1,2,2-tetrachloroethane, nitromethane, nitrobenzene, chlorobenzene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, N-methylpyrrolidone, tetrahydrofuran, ethyl acetate, cyclopentyl methyl ether, and the like.

[0113] As the above solvent, it is preferable to reduce halogen-based solvents such as chloroform and chlorobenzene, which are highly environmentally harmful, especially halogens containing chlorine and bromine. The usage amount of these solvents is preferably 100% by mass or less, more preferably 50% by mass or less, still more preferably 10% by mass or less, and even more preferably 1% by mass or less, based on the polymer after the step of synthesizing the polymer.

[0114] The oxidative polymerization using a catalyst will be described. In the above polymerization step, the above monomer components are polymerized in the presence of a catalyst. For example, it is more preferable to carry out the polymerization reaction by heating a composition containing the above monomer components and the catalyst. A composition containing monomer components and a catalyst is also referred to as a raw material composition, and a composition from the start to the end of the polymerization reaction is also referred to as a reaction composition. Also, a composition obtained by the polymerization reaction is also referred to as a polymer composition.

[0115] As the above-mentioned catalyst, a catalyst having an oxidative polymerization activity with respect to a monomer component containing the above-mentioned disulfide compound and / or thiol compound (oxidative polymerization catalyst) is preferable. The above-mentioned catalyst is not particularly limited, but substances containing metal elements such as vanadium (V), zirconium (Zr), titanium (Ti), cobalt (Co), nickel (Ni), manganese (Mn), iron (Fe), etc. are preferable. As the substance containing a metal, its form is not particularly limited, and examples include metals, metal compounds, and other forms containing the metal element.

[0116] Examples of the above-mentioned metal include metals consisting only of the metal (simple substance) and alloys having the metal as a main component. The above-mentioned metal compound is not particularly limited as long as it is a compound containing a metal, and examples include inorganic compounds, organic acid salts, complexes (coordination compounds), etc. Examples of the above-mentioned inorganic compounds include halides, sulfates, nitrates, phosphates, silicates, carbonates, hydroxides, oxides, sulfides, tellurides, intermetallic compounds, etc. Among them, halides are preferable. As the above-mentioned halides, fluorides, chlorides, bromides, and iodides are preferable, and chlorides are more preferable. The above-mentioned organic acid salts are not particularly limited as long as they are organic acid salts containing a metal element, and examples include carboxylates, sulfonates, etc. As the above-mentioned carboxylates, acetates, oxalates, etc. are preferable. As the above-mentioned sulfonates, paratoluenesulfonates, trifluoromethanesulfonates, etc. are preferable. The above-mentioned complexes are not particularly limited as long as they are complexes containing a metal element, and examples include ammine complexes, cyano complexes, halogeno complexes, hydroxy complexes, phthalocyanine complexes, porphyrin complexes, carbonyl complexes, salen complexes, ethylenediamine complexes, β-diketone complexes, β-diketoester complexes, etc.

[0117] Examples of the above-mentioned other forms as the substance containing the above-mentioned metal element include forms in which metal ions such as monovalent ions and trivalent ions of the metal are contained as cations in cation exchangers such as zeolites and micas.

[0118] The substance containing the above metal element may be used alone or in combination of two or more. In the above raw material composition, the form of existence of the substance containing the above metal element is not particularly limited. For example, it may be dispersed in the form of particles or the like in the above raw material composition, or may exist in the form of a monomer component or in a state dissolved in the solvent when a solvent is used. The solvent will be described later. The same applies to the form of existence of the substance containing the above metal element in the above reaction composition.

[0119] Among the substances containing the above metal element, a substance containing vanadium as a metal element and a substance containing iron (these are also referred to as vanadium-containing substance and iron-containing substance respectively) are each preferable in terms of high catalytic activity for oxidative polymerization.

[0120] As the above iron-containing substance, it is preferable to mainly contain iron as a metal element. Specifically, the content of iron with respect to the total content of metal elements contained in the iron-containing substance is preferably 50 mol% or more, more preferably 80 mol% or more, further preferably 95 mol% or more, still more preferably 98 mol% or more, and particularly preferably 100 mol% based on 100 mol%.

[0121] As the above vanadium-containing substance, it is preferable to mainly contain vanadium as a metal element, and the preferable content of vanadium with respect to the total amount of metal elements is the same as the content of iron in the iron-containing substance. The specific forms and preferable forms of the vanadium-containing substance and the iron-containing substance conform to the respective forms described above for the substance containing the above metal element.

[0122] As the above iron-containing substance, an iron compound having chlorine in the molecule is preferable. Also, a compound containing iron with an oxidation number of 3 or more is preferable. Examples of such iron-containing substances include ferric chloride (Fe(Cl)3), 5,10,15,20-tetraphenyl-21H,23H-porphine iron(III), iron(III) trifluoromethanesulfonate, etc., and are particularly preferable.

[0123] As the above vanadium-containing substance, a metal containing vanadium and an oxovanadium compound having a V=O bond in the vanadium compound molecule are preferable. As the above oxovanadium compound, for example, vanadyl acetylacetonate, oxovanadium salen complex, N,N'-bis(salicylidene)ethylenediamine oxovanadium, phthalocyanine oxovanadium, tetraphenylporphyrin oxovanadium, etc. can be mentioned. The amount of the above catalyst used in the above polymerization is not particularly limited, but the total content of the metal elements contained in the above catalyst with respect to 100 mol% of the above monomer component is preferably in the range of 0.001 to 50 mol%. From the viewpoint of easily obtaining a sulfur-containing polymer having a high molecular weight and / or from the viewpoint of easily achieving a purification process for easily removing catalyst residues, 30 mol% or less is preferable, 10 mol% or less is more preferable, 5 mol% or less is further preferable, and from the viewpoint of enhancing the polymerization reactivity, 0.01 mol% or more is more preferable, 0.1 mol% or more is further preferable, and 1 mol% or more is particularly preferable.

[0124] The above polymerization is preferably carried out in the presence of oxygen. By carrying out in the presence of oxygen, the oxidative polymerization reaction is further promoted. As a specific embodiment, a method of supplying an oxygen-containing gas during the above polymerization reaction is preferable. That is, the above polymerization is preferably carried out under the supply of an oxygen-containing gas. For example, a method of supplying an oxygen-containing gas to the gas phase portion during the polymerization reaction, a method of bubbling an oxygen-containing gas into the reaction composition during the polymerization reaction, etc. are adopted.

[0125] By carrying out the above polymerization reaction in the presence of oxygen gas, it is considered that the dehydrogenation reaction of hydrogen from the carbon constituting the aromatic ring contained in the monomer component can be promoted. Also, in the above polymerization step, usually, the oxidation number of the metal contained in the catalyst can change, but by carrying out the polymerization reaction in the presence of oxygen gas, the valence of the metal contained in the above catalyst can be maintained at a high oxidation number, so it is considered that the oxidative polymerization can be further promoted. From such a viewpoint, a method of continuously supplying an oxygen-containing gas to the reaction composition during the polymerization reaction is preferable, and among them, the bubbling method is preferable.

[0126] The above oxygen-containing gas is preferably a gas containing oxygen molecules (O2). The oxygen-containing gas may contain gas components other than oxygen molecules (O2). The gas components other than oxygen molecules (O2) contained in the oxygen-containing gas are not particularly limited, but preferably include noble gases such as helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn); and inert gases such as nitrogen (N2). In addition to the above inert gases, carbon dioxide (CO2), water vapor, etc. may be contained.

[0127] The content rate of oxygen molecules (O2) in the above oxygen-containing gas is not particularly limited, but at normal temperature (25 °C) and under 1 atm, the volume ratio of oxygen molecules (O2) in the oxygen-containing gas is preferably 0.1 to 100% by volume with respect to 100% by volume of the oxygen-containing gas. More preferably, it is 1% by volume or more, and still more preferably 10% by volume or more. The upper limit is more preferably 60% by volume or less, and still more preferably 30% by volume or less.

[0128] The total content of oxygen molecules (O2) and inert gas in the above oxygen-containing gas is not particularly limited, but at normal temperature (25 °C) and under 1 atm, the total volume ratio of oxygen molecules (O2) and inert gas in the oxygen-containing gas is preferably 80 to 100% by volume with respect to 100% by volume of the oxygen-containing gas. More preferably, it is 95% by volume or more, and still more preferably 98% by volume or more.

[0129] The above oxygen-containing gas is not particularly limited, and examples include oxygen gas, a mixed gas of oxygen and nitrogen, air, etc. From the viewpoint of excellent economy, it is preferable to use air. The water vapor concentration in the above oxygen-containing gas is not particularly limited, but it is preferably 1000 g / m 3 or less, more preferably 10 g / m 3 or less, still more preferably 1 g / m 3 or less, most preferably 0.1 g / m 3 or less, and dry air is most preferable.

[0130] The supply amount of the above oxygen-containing gas is not particularly limited, but per 1 m 3 of the total volume of the reaction composition, the supply amount (supply rate) per minute is 0.0001 m 3 / min to 10 m 3 / min is preferable. From the viewpoint of increasing the reaction rate, more preferably, it is 0.0005 m 3 / min or more, and even more preferably 0.001 m 3 / min or more. The upper limit is more preferably 1 m 3 / min or less, and even more preferably 0.1 m 3 / min or less.

[0131] The supply amount of the above oxygen-containing gas is not particularly limited, but per 1 m 3 of the total volume of the reaction composition, the supply amount (supply rate) of oxygen (O2) per minute is 0.00002 m 3 / min to 2 m 3 / min is preferable. From the viewpoint of increasing the reaction rate, more preferably, it is 0.0001 m 3 / min or more, and even more preferably 0.0002 m 3 / min or more. The upper limit is more preferably 0.2 m 3 / min or less, and even more preferably 0.02 m 3 / min or less.

[0132] In the above polymerization step, it is preferable to further use an acid and / or its salt. By using an acid and / or its salt in combination with the above catalyst, it becomes easier to control the molecular weight of the polymer obtained by the polymerization reaction to a high range, and it becomes easier to obtain a high molecular weight sulfide-containing polymer even in a short time.

[0133] As the above acid, a Bronsted acid is preferred. For example, inorganic acids such as phosphoric acid, phosphonic acid, nitric acid, hydrochloric acid, hydrobromic acid, sulfuric acid, persulfuric acid, sulfurous acid; sulfonic acids such as methanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, 10-camphorsulfonic acid, trifluoromethanesulfonic acid, 1,1,2,2-tetrafluoroethanesulfonic acid; carboxylic acids such as acetic acid, trifluoroacetic acid, perfluoropropionic acid, perfluorobutyric acid, benzoic acid, etc. can be mentioned.

[0134] As the above acid, an acid with an acid dissociation constant of -19 to 4 is preferred. More preferably, the acid dissociation constant is 3 or less and -8 or more.

[0135] The salt of the above acid is not particularly limited as long as it is a salt of the above acid. For example, salts of Group 1 metal elements of the periodic table such as sodium and potassium, Group 2 metal elements of the periodic table such as magnesium and calcium, ammonium, etc. with the above acid are preferred. Among them, for example, sodium persulfate, ammonium persulfate, sodium toluenesulfonate, sodium trifluoromethanesulfonate, etc. are preferred. As the salt with the above acid, the pH at 25 °C when dissolved in pure water is preferably 1 to 6.9, and more preferably 2 to 6.

[0136] Examples of acids with an acid dissociation constant of -19 to 4 include inorganic acids such as phosphoric acid, nitric acid, sulfuric acid, persulfuric acid, sulfurous acid, hydrochloric acid, hydrobromic acid; sulfonic acids such as methanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, 10-camphorsulfonic acid, trifluoromethanesulfonic acid, 1,1,2,2-tetrafluoroethanesulfonic acid; chlorocarboxylic acids such as chloroacetic acid, dichloroacetic acid, trichloroacetic acid; fluorocarboxylic acids such as fluoroacetic acid, difluoroacetic acid, trifluoroacetic acid, perfluoropropionic acid, perfluorobutyric acid, 4-fluorobenzoic acid, etc. Among them, 10-camphorsulfonic acid, trifluoromethanesulfonic acid, and persulfuric acid are preferred. The above acid and / or its salt may be used alone or in combination of two or more.

[0137] The amount of the acid and / or its salt is preferably 0.01 to 100 mol%, more preferably 0.1 to 10 mol%, and still more preferably 0.5 to 5 mol% based on 100 mol% of the monomer component. Also, the amount of the acid and / or its salt is preferably 0.1 to 1000 mol%, more preferably 1 to 100 mol%, and still more preferably 5 to 50 mol% based on 100 mol% of the total amount of the metal elements contained in the substance containing the metal element.

[0138] From the viewpoint of improving the reaction efficiency, the pH of the entire reaction system (raw material composition containing the acid and / or its salt) to which the above acid and / or its salt is added is preferably pH 0.1 to 7, more preferably 1 to 6, and most preferably 2 to 5. The pH is the value measured when the reaction system (raw material composition containing the acid and / or its salt) is measured as it is, and is measured with pH test paper or a pH meter.

[0139] In the above polymerization step, the polymerization temperature is not particularly limited as long as polymerization, preferably oxidative polymerization, proceeds, but from the viewpoint of facilitating oxidative polymerization, it is preferably 0 to 300 °C, more preferably 10 °C or higher, still more preferably 100 °C or higher, and from the viewpoint of suppressing side reactions, it is more preferably 200 °C or lower, still more preferably 180 °C or lower. The polymerization time is not particularly limited, but is usually 0.1 to 300 hours, preferably 1 to 200 hours, more preferably 5 to 100 hours, and still more preferably 10 to 50 hours.

[0140] The above polymerization reaction can be carried out in a molten state of the monomer component, or can also be carried out in a state where the monomer component is dissolved or dispersed in a solvent. When carried out in a molten state, it is preferable to set the polymerization temperature to a temperature equal to or higher than the melting point of the monomer component. In that case, it is preferable to heat the above raw material composition and carry out the polymerization reaction while maintaining the temperature of the above reaction composition at a temperature equal to or higher than the melting point of the monomer component.

[0141] When the monomer component is dissolved or dispersed in a solvent, the polymerization may be carried out at a temperature below the boiling point of the solvent, or may be carried out under reflux conditions, or may be carried out under pressure while heating to a temperature above the boiling point.

[0142] The above solvent is not particularly limited, but preferred solvents include, for example, dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, tetrachloroethylene, 1,1,2,2-tetrachloroethane, nitromethane, nitrobenzene, chlorobenzene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, N-methylpyrrolidone, tetrahydrofuran, ethyl acetate, cyclopentyl methyl ether and the like. The amount of the above solvent used is not particularly limited, but it is preferably 1 to 10,000 parts by mass, more preferably 10 to 1,000 parts by mass, based on 100 parts by mass of the above monomer component as a raw material.

[0143] In the above polymerization, the monomer component may be sequentially added during the polymerization reaction. In the above polymerization step, after oxidatively polymerizing the above thiol compound to obtain a disulfide compound, polymerization may be carried out in multiple stages such as oxidatively polymerizing the obtained disulfide compound.

[0144] By holding the composition (raw material composition) containing the above monomer component and the above catalyst at the above polymerization temperature for the above polymerization time, a polymerization reaction of the above monomer component occurs, and a sulfur-containing polymer (sulfide-containing polymer) is generated, and a polymer composition containing at least the above polymer (sulfide-containing polymer) and the above catalyst is obtained.

[0145] The production method of the present invention is characterized by having the above oxidation step. As described above, it preferably has the above polymer terminal control step and preferably has the above polymerization step. The most preferred embodiment of the production method of the present invention includes a production method comprising the above polymerization step, the above oxidation step, and the above polymer terminal control step. For example, it is a production method comprising the following steps (1) to (3). (1) Polymerization step: Polymerize a monomer component containing a sulfur-containing monomer to obtain a sulfur-containing polymer (sulfide-containing polymer) having a sulfide skeleton in the main chain. (2) Oxidation step: Oxidize the sulfide-containing polymer to obtain a sulfoxide-containing polymer. (3) Polymer terminal control step: Perform a reaction to control the polymer terminal.

[0146] Here, as described above, it is preferable to perform the above polymerization step (1) before the above oxidation step (2), and the timing of performing the above polymer terminal control step (3) is as described above. Among them, the above polymer terminal control step (3) is preferably performed after the above oxidation step (2) or simultaneously with the above oxidation step (2), and it is preferable to start the terminal control reaction in the polymer terminal control step after the oxidation reaction in the above oxidation step has started. That is, it is preferable to start the above oxidation reaction first, and then perform the terminal control reaction after the above oxidation reaction is completed or after the above oxidation reaction has proceeded to a certain extent.

[0147] <Purification step> The production method of the present invention preferably has a purification step in addition to the above oxidation step, and more preferably has a purification step in addition to the above oxidation step, the above polymer terminal control step, and the above polymerization step. When oxidative polymerization using a catalyst is performed in the above polymerization step, the metal component contained in the metal compound used as the catalyst is likely to cause coloring depending on the type of metal, and it is desirable to remove it. However, since the above metal component is strongly coordinated to the terminal of the polymer (sulfide-containing polymer), it has been difficult to remove.

[0148] Even if the polymer (sulfide-containing polymer) is a polymer (sulfide-containing polymer) containing a metal component, by subjecting it to the oxidation step in the present invention, not only the oxidation of sulfur atoms in the main chain skeleton of the polymer but also the terminal structure changes, so it is considered that the coordination force of sulfur atoms in the polymer to the metal component decreases and it becomes easier to remove.

[0149] Therefore, as the above purification method, a conventionally known purification method can be used. For example, it is preferable to use the reprecipitation method. The reprecipitation method is not particularly limited. For example, a composition containing a polymer such as a sulfide-containing polymer or a sulfoxide-containing polymer is dropped into hydrochloric acid-acidic methanol to precipitate the polymer, which is then filtered to obtain a precipitate, and the obtained precipitate is washed with a lower alcohol such as water or methanol. It is also preferable to remove components derived from the compound (Z) used in the oxidation step by the above purification method.

[0150] As the above purification step, a method using a conventionally known adsorbent such as activated carbon can also be used to remove components derived from the compound (Z) used in the oxidation step and impurity components derived from the polymerization step. It is also preferable to use the reprecipitation method and the method using an adsorbent in combination. The timing of performing the above purification step is not particularly limited, and it may be performed before the oxidation step, after the oxidation step, or after the polymer terminal control step. That is, the sulfide-containing polymer obtained after performing the above purification step may be subjected to the oxidation step, or the composition containing the polymer (sulfoxide-containing polymer) obtained in the oxidation step or the polymer terminal control step may be subjected to the purification step.

[0151] Among them, it is preferable to perform the above purification step on the composition containing the polymer obtained after performing any of the above polymerization step, oxidation step, and polymer terminal control step, because a sulfoxide-containing polymer with fewer impurities derived from the raw materials used in each step can be obtained. For example, when the production method of the present invention has a polymer terminal control step, it is preferable to perform purification on the composition containing the polymer (sulfoxide-containing polymer) obtained after performing the oxidation step and the polymer terminal control step. When the production method of the present invention does not have a polymer terminal control step, it is preferable to perform purification on the composition containing the polymer (sulfoxide-containing polymer) obtained after performing the oxidation step.

[0152] In addition to the above polymerization step, oxidation step, polymer terminal control step, and purification step, the production method of the present invention may have other steps. Examples of the above other steps include an aging step, a neutralization step, a dilution step, a drying step, a concentration step, a solvent replacement step, a dissolution step, and the like. These steps can be carried out by known methods.

[0153] 2. Regarding the sulfur-containing polymer obtained by the production method of the present invention The sulfur-containing polymer obtained by the above-described production method of the present invention is a sulfur-containing polymer having a sulfoxide skeleton in the main chain (sulfoxide-containing polymer). Among the sulfur-containing polymers obtained by the production method of the present invention, preferred sulfoxide-containing polymers will be described below.

[0154] The above sulfoxide-containing polymer has excellent transmittance after heating. The transmittance after heating can be determined, for example, by the visible light transmittance after heating at 260 °C. Specifically, a sample containing a sulfoxide-containing polymer is heated in air at 260 °C for 10 minutes, and the transmittance Ta (%) after heating is measured.

[0155] As the above sample, a laminate of a colorless transparent glass substrate and a thin film made of a 1-μm-thick sulfoxide-containing polymer formed on one surface thereof is used. The above sample can be prepared, for example, by dissolving a sulfoxide-containing polymer in a solvent, applying the solution to one surface of a colorless transparent glass substrate, and drying it. As a preferred specific example, a solution in which a sulfoxide-containing polymer is dissolved to a concentration of 5% by mass in hexafluoro-2-propanol is prepared, and the obtained solution is spin-coated on one surface of a glass substrate (manufactured by Matsunami Glass Industry Co., Ltd., S1111) having excellent visible light transmittance at about 500 rpm × 60 s and dried at 100 °C for 10 minutes to form a thin film (thickness: 1 μm).

[0156] The measurement of visible light transmittance can be carried out using a commercially available spectrophotometer. For example, a spectrophotometer (Ultraviolet-Visible-Infrared Spectrophotometer V-700 series manufactured by JASCO Corporation) can be used. As the visible light transmittance for determining the transmittance after heating, usually, the transmittance at a wavelength of 400 nm is adopted. Also, parallel line transmittance is adopted as the transmittance.

[0157] In the above sulfoxide-containing polymer, the transmittance (Ta) after heating obtained by the above evaluation method is preferably 81% or more, more preferably 82% or more, and even more preferably 85% or more.

[0158] Also, in the above sulfoxide-containing polymer, in the above evaluation method, the transmittance (Tb) before heating at 260 °C is preferably 82% or more, more preferably 83% or more, and even more preferably 85% or more. The above transmittance (Tb) can be measured in the same manner as the transmittance (Ta). In the above sulfoxide-containing polymer, the absolute value of the difference between the transmittance (Ta) and the transmittance (Tb) is preferably 5% or less, more preferably 3% or less, even more preferably 2% or less, and particularly preferably 1% or less.

[0159] The above sulfoxide-containing polymer is preferably a sulfur-containing polymer having at least the structural unit (B) represented by the above general formula (2) as described in the description of the sulfide-containing polymer, and for the substituents that X 2 and X 2 may have, including these preferred embodiments, it is as described in the description of the sulfide-containing polymer. Further, the above sulfoxide-containing polymer is preferably a sulfur-containing polymer having at least the structural unit (B-1) represented by the above general formula (2-1), and for the substituents that R 2 and R 2 may have, including these preferred embodiments, it is as described in the description of the sulfide-containing polymer.

[0160] The above-mentioned sulfoxide-containing polymer is not further limited as long as it is a sulfur-containing polymer having a sulfoxide skeleton in the main chain, preferably a sulfur-containing polymer having the above-mentioned structural unit (B), but it may further contain other structural units. For example, it may further contain the structural unit (A) represented by the above general formula (1) and / or the structural unit (C) represented by the above general formula (3) described in the description of the sulfide-containing polymer.

[0161] In the above-mentioned sulfoxide-containing polymer, the structural unit (A) is preferably the structural unit (A-1) represented by the above general formula (1-1), and the structural unit (C) is preferably the structural unit (C-1) represented by the above general formula (3-1). X 1 and X 1 substituents that may be possessed, X 3 and X 3 substituents that may be possessed, R 1 and R 1 substituents that may be possessed, R 3 and R 3 For the substituents that may be possessed by R, including these preferred embodiments, it is as described in the description of the sulfide-containing polymer.

[0162] The above-mentioned sulfoxide-containing polymer may be a polymer containing only the above-mentioned structural unit (B), or may be a copolymer further containing the structural unit (A) and / or the structural unit (C). In the case of the above copolymer, its form is not particularly limited. For example, it may be an alternating copolymer, a block copolymer, or a random copolymer. The above-mentioned sulfoxide-containing polymer may have one or more of the above-mentioned structural units (A), (B), or (C).

[0163] The content ratio of the above-mentioned structural unit (B) in the above-mentioned sulfoxide-containing polymer is preferably higher than the content ratio of the structural unit (B) in the sulfide-containing polymer subjected to the oxidation step. In the above-mentioned sulfoxide-containing polymer, the content ratio of the above-mentioned structural unit (B) is preferably 10 to 99 mol%, more preferably 30 to 97 mol%, and still more preferably 60 to 95 mol% with respect to 100 mol% of all the structural units of the polymer. The total content ratio of the above-mentioned structural unit (A) and structural unit (C) is preferably 1 to 90 mol%, more preferably 3 to 70 mol%, and still more preferably 5 to 40 mol% with respect to 100 mol% of all the structural units. The content ratio of the above-mentioned structural unit (A) is preferably 1 to 90 mol%, more preferably 3 to 70 mol%, and still more preferably 5 to 40 mol% with respect to 100 mol% of all the structural units.

[0164] In the above-mentioned sulfoxide-containing polymer, the total content ratio of the above-mentioned structural units (A), (B) and (C) is preferably 50 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, still more preferably 95 mol% or more, and particularly preferably 100 mol% with respect to 100 mol% of all the structural units of the polymer.

[0165] The above-mentioned sulfoxide-containing polymer may have another structural unit (D) other than the above-mentioned structural units (A), (B) and (C). Examples of the above-mentioned structural unit (D) include structural units having at least the above-mentioned reactive functional groups. The monomers into which the above-mentioned structural unit (D) can be introduced are as described in the description of the sulfide-containing polymer. The content ratio of the above-mentioned structural unit (D) is preferably 0 to 50 mol%, more preferably 0 to 20 mol%, and still more preferably 0 to 5 mol% with respect to 100 mol% of all the structural units of the polymer.

[0166] The above-mentioned sulfoxide-containing polymer preferably has the above-mentioned reactive functional groups at the main chain terminals and / or side chains. By having the above-mentioned reactive functional groups at least at the main chain terminals or side chains, the sulfoxide-containing polymer obtained after the oxidation reaction can exhibit excellent physical properties due to the above-mentioned reactive functional groups. The case where the above-mentioned reactive functional groups are present in the side chains includes not only the case where the above-mentioned reactive functional groups are present in the side chains of the above-mentioned sulfoxide-containing polymer, but also the case where the substituents in the structural units (A) to (C) represented by the above general formulas (1) to (3) are the above-mentioned reactive functional groups or groups containing the above-mentioned reactive functional groups.

[0167] The above-mentioned sulfoxide-containing polymer preferably has a heavy metal content of 0.0001 ppm or more and 1200 ppm or less based on the sulfur-containing polymer. The above-mentioned sulfoxide-containing polymer has a high refractive index and excellent light transmittance. Also, it has excellent transmittance after heating. The heavy metal content is more preferably 500 ppm or less, still more preferably 200 ppm or less, and even more preferably 100 ppm or less based on the polymer (solid content). Also, from the viewpoint that the molded article using the above-mentioned sulfoxide-containing polymer is likely to have excellent toughness, the heavy metal content is more preferably 0.001 ppm or more, still more preferably 0.01 ppm or more based on the sulfoxide-containing polymer (solid content). The heavy metal content can be determined by the above-mentioned ICP emission spectrometry.

[0168] The above-mentioned sulfoxide-containing polymer preferably has an element content ratio (O / S) of the oxygen atom O bonded to the sulfur atom S in the main chain and the sulfur atom S in the main chain of 0.1 to 1.5. When the above-mentioned element content ratio is within the above range, the transparency and refractive index become higher. The sulfur atom S in the above main chain specifically means, for example, in the structural unit (B) represented by the above general formula (2), the sulfur atom S of -SO- in the main chain. In the structural unit (A) represented by the above general formula (1), it means the sulfur atom S of -S- in the main chain, and in the structural unit (C) represented by the above general formula (3), it means the sulfur atom S of -SO2- in the main chain. The oxygen atom bonded to the sulfur atom S in the above main chain specifically means, for example, in the structural unit (B) represented by the above general formula (2), the oxygen atom O of -SO- in the main chain, and in the structural unit (C) represented by the above general formula (3), it means the oxygen atom O of -SO2- in the main chain.

[0169] The above element content ratio (O / S) is more preferably 0.3 or more, still more preferably 0.5 or more, in terms of further improving transparency, and more preferably 1.3 or less, still more preferably 1.1 or less, in terms of further increasing the refractive index. The above element content ratio can be determined by evaluating and measuring the peak intensities of the 1s orbital of oxygen atoms (O1s), the 1s orbital of carbon atoms (C1s), and the 2p orbital of sulfur atoms (S2p) using an X-ray photoelectron spectrometer (XPS).

[0170] The weight average molecular weight (Mw) of the above sulfoxide-containing polymer is preferably 500 to 10,000,000. When the weight average molecular weight is within the above range, it can be suitably used as an optical material. From the perspective of improving mechanical properties, the above weight average molecular weight is more preferably 1000 or more, still more preferably 3000 or more, still more preferably 10,000 or more, and from the perspective of reducing the melt viscosity, it is more preferably 1,000,000 or less, still more preferably 100,000 or less.

[0171] The dispersity (weight-average molecular weight / number-average molecular weight) of the above-mentioned sulfoxide-containing polymer is preferably 1 or more and 10 or less. When the dispersity is within the above range, molding becomes easy. In terms of further improving the moldability, the dispersity is more preferably 5 or less, and even more preferably 3 or less. The above weight-average molecular weight and number-average molecular weight can be determined by measuring with gel permeation chromatography (GPC) method, specifically, by the method described in the examples below. The dispersity can be determined by dividing the weight-average molecular weight by the number-average molecular weight.

[0172] The above-mentioned sulfoxide-containing polymer preferably has a glass transition temperature (Tg) of 80 to 250 °C. When the glass transition temperature is within the above range, molding processing can be easily performed. From the viewpoint of increasing the heat resistance, the above glass transition temperature is more preferably 90 °C or higher, even more preferably 100 °C or higher, and from the viewpoint of easily performing molding processing, it is more preferably 200 °C or lower. The above glass transition temperature can be determined by a method of evaluating from the intersection of the baseline and the tangent at the inflection point from the DSC curve obtained by heating from room temperature to 250 °C (heating rate 10 °C / min) in a nitrogen gas atmosphere using a differential scanning calorimeter (DSC).

[0173] The above-mentioned sulfoxide-containing polymer preferably has a refractive index of 1.69 or more. When the refractive index is within the above range, it can be widely and preferably used for various applications such as optical materials (components), mechanical part materials, electrical and electronic part materials, automotive part materials, civil engineering and construction materials, molding materials, etc., as well as materials for paints and adhesives. The above refractive index is more preferably 1.7 or more, and even more preferably 1.71 or more. The above refractive index can be determined by forming a film with a thickness of 50 nm using the above polymer as a measurement sample, using a spectroscopic ellipsometer UVISEL (manufactured by HORIBA Scientific), and measuring using the Na D line (589 nm).

[0174] The above-mentioned sulfoxide-containing polymer preferably has an Abbe number of 10 or more. When the Abbe number is within the above range, light dispersion is small, and it can be used as an optical material suitable for lenses. The above Abbe number is more preferably 15 or more, still more preferably 18 or more, and even more preferably 20 or more. From the viewpoint of adjusting light dispersibility, the above Abbe number is preferably 60 or less, and more preferably 55 or less. The above Abbe number can be obtained by forming a film using the above polymer in the same manner as when measuring the refractive index, measuring the refractive indices at the D line (589.3 nm), F line (486.1 nm), and C line (656.3 nm) using the above spectroscopic ellipsometer, and using the following calculation formula. Abbe number (vD) = (nD - 1) / (nF - nC) In the formula, nD, nF, and nC represent the refractive indices at the Fraunhofer D line (589.3 nm), F line (486.1 nm), and C line (658.3 nm), respectively.

[0175] The sulfoxide-containing polymer obtained by the production method of the present invention is excellent in transmittance after heating. Further, according to a preferred embodiment, since it is a polymer having a sulfoxide skeleton in the main chain, it has a high refractive index and is excellent in optical visible light transmittance. According to that preferred embodiment, it is also excellent in solubility and processability. Moreover, the polymer obtained in a preferred embodiment in the production method of the present invention has few impurities used in the polymerization step or the like, and the material using the polymer is excellent in colorless transparency and suppresses coloring over time. Therefore, the sulfur-containing polymer (sulfoxide-containing polymer) obtained by such a production method of the present invention can be used alone or as a composition combined with other components for various applications such as optical materials.

[0176] 3. Composition containing the sulfoxide-containing polymer obtained by the production method of the present invention The composition containing the sulfoxide-containing polymer obtained by the production method of the present invention will be described. This composition is also referred to as a sulfoxide-containing polymer composition or a polymer composition. The content of the sulfoxide-containing polymer in the sulfoxide-containing polymer composition is preferably 1 to 100% by mass, more preferably 10 to 50% by mass, and still more preferably 30 to 70% by mass based on 100% by mass of the total solid content of the sulfoxide-containing polymer composition.

[0177] The above-mentioned other components are not particularly limited and can be appropriately selected from known components according to the purpose and use of the sulfoxide-containing polymer composition. For example, by selecting an inorganic substance as the other component, transparency and refractive index can be controlled. The sulfoxide-containing polymer composition containing the above-mentioned sulfoxide-containing polymer and an inorganic substance is also one of the embodiments of the sulfoxide-containing polymer obtained by the production method of the present invention.

[0178] Examples of the above-mentioned inorganic substances include metals, inorganic oxides, inorganic nitrides, inorganic carbides, inorganic sulfides, inorganic hydroxides, etc. The above-mentioned inorganic substances may be used alone or in combination of two or more. Examples of the above-mentioned metals include lithium (Li), sodium (Na), potassium (K), boron (B), magnesium (Mg), calcium (Ca), manganese (Mn), strontium (Sr), barium (Ba), titanium (Ti), zirconium (Zr), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), aluminum (Al), tin (Sn), silicon (Si), cesium (Ce), indium (In), etc.

[0179] As the inorganic oxide, a metal oxide containing a metal element is preferred. Examples of the metal oxide include a single metal oxide composed of one kind of metal element, a composite oxide which is an oxide composed of two or more kinds of metal elements, and a solid solution oxide in which a foreign element is solid-solved in the single metal oxide or the composite oxide. The foreign element may be a metal element or a non-metal element such as nitrogen or fluorine other than oxygen. Examples of the metal element include the metal elements described above. Examples of the single metal oxide include magnesium oxide, calcium oxide, strontium oxide, barium oxide, titanium oxide, zinc oxide, cerium oxide, silicon oxide, tin oxide, zirconium oxide, aluminum oxide, indium oxide, and the like. Examples of the composite oxide include perovskite-type composite oxides such as barium titanate, barium strontium titanate, strontium titanate, barium zirconium strontium titanate, barium zirconium titanate, and lead titanate zirconate; spinel-type composite oxides such as spinel and lithium titanate; and composite oxides such as aluminum titanate. Examples of the solid solution oxide include a solid solution oxide in which a foreign metal element and / or a non-metal element other than oxygen, such as nitrogen or fluorine, is solid-solved in the single metal oxide or the composite oxide.

[0180] As the inorganic nitride, a metal nitride is preferred, and examples thereof include boron nitride, carbon nitride, aluminum nitride, and the like. As the inorganic carbide, a metal carbide is preferred, and examples thereof include silicon carbide, calcium carbide, titanium carbide, boron carbide, and the like. As the inorganic sulfide, a metal sulfide is preferred, and examples thereof include copper sulfide, zinc sulfide, cadmium sulfide, and the like. As the inorganic hydroxide, a metal hydroxide is preferred, and examples thereof include aluminum hydroxide, magnesium hydroxide, barium hydroxide, and the like.

[0181] Among them, the inorganic substance is preferably an inorganic oxide and more preferably a metal oxide in that it has a wide band gap (visible light transparent). Further, among the above inorganic substances, since there is no absorption or little absorption in the visible light region, a colorless and transparent composition with suppressed coloring by the inorganic substance is easily obtained. Oxides mainly composed of metal elements such as Ti, Zr, Ce, Zn, In, Al, Si, and Sn are more preferable, and titanium oxide (TiO2), zirconium oxide (ZrO2), cerium oxide (CeO2), zinc oxide (ZnO), indium oxide (In2O3), aluminum oxide (Al2O3), silicon oxide (SiO2), and tin oxide (SnO2) are particularly preferable.

[0182] Among the above inorganic substances, zirconium oxide, titanium oxide, and silicon dioxide are more preferable in terms of further improving the transparency of the sulfoxide-containing polymer composition and reducing the linear expansion of the composition. From the viewpoint of improving the refractive index of the sulfoxide-containing polymer composition, zirconium oxide and titanium oxide are more preferable. Further, perovskite-type composite oxides are preferable in that they have a high relative dielectric constant and can be suitably used as ferroelectric materials and piezoelectric materials for the sulfoxide-containing polymer composition. Boron nitride, aluminum hydroxide, and aluminum titanate are preferable in that they have a high thermal conductivity and can be suitably used as heat dissipation materials for the sulfoxide-containing polymer composition.

[0183] From the viewpoint of imparting antistatic or conductive properties while suppressing coloring due to the addition of an inorganic substance to the sulfoxide-containing polymer composition, solid solution oxides in which a foreign metal element or an additive element such as fluorine is solid-dissolved in zinc oxide (ZnO), indium oxide (In2O3), or tin oxide (SnO2) are preferable. For example, zinc oxide in which In, Al, or Ga is solid-dissolved, indium oxide in which Sn or Ti is solid-dissolved, and tin oxide in which Sb or F is solid-dissolved are more preferable.

[0184] The shape of the above-mentioned inorganic substance is not particularly limited and may be any of amorphous, granular, plate-like, fibrous, block-like, etc., but granular is preferred. The above-mentioned inorganic substance may be surface-treated. The above-mentioned surface treatment is not particularly limited as long as it does not affect the effects of the present invention, and known methods such as a method using a silane coupling agent, a method of reacting a compound having a phosphate group, and a method of reacting a compound having a carboxylic acid group can be mentioned.

[0185] The average particle diameter of the above-mentioned inorganic substance is preferably 1 nm or more and 1000 nm or less. When the average particle diameter of the above-mentioned inorganic substance is within the above range, the light transmittance in the visible light region and the infrared region can be improved. The average particle diameter of the above-mentioned inorganic substance is more preferably 5 nm or more, further preferably 10 nm or more, more preferably 100 nm or less, and further preferably 50 nm or less. The above average particle diameter is obtained by observing the above-mentioned inorganic substance with SEM (magnification 1000 to 100,000 times, preferably 10,000 times), analyzing the obtained image, obtaining the particle diameters (equivalent diameters of circular areas) of about 10 to 1000 individual particles (primary particles), and evaluating the 50% particle diameter according to the particle size distribution based on the number. For image analysis, known image analysis software (for example, Mac-View manufactured by Mountech) can be used.

[0186] The content of the above-mentioned inorganic substance is not particularly limited and can be appropriately set according to the purpose and use of the above-mentioned sulfoxide-containing polymer composition. For example, the content of the above-mentioned inorganic substance is preferably 10 parts by mass or more, more preferably 30 parts by mass or more, even more preferably 50 parts by mass or more, particularly preferably 70 parts by mass or more, and most preferably 80 parts by mass or more with respect to 100 parts by mass of the above-mentioned sulfoxide-containing polymer in terms of further improving transparency and reducing the linear expansion coefficient. Also, from the viewpoint of reducing the melt viscosity during the production of the resin molded product, the content of the above-mentioned inorganic substance is preferably 90 parts by mass or less, more preferably 80 parts by mass or less, further preferably 70 parts by mass or less, and even more preferably 50 parts by mass or less with respect to 100 parts by mass of the above-mentioned sulfoxide-containing polymer.

[0187] In addition to the above-mentioned sulfoxide-containing polymer and inorganic substance, the sulfoxide-containing polymer composition may contain, for example, pigments, dyes, antioxidants, ultraviolet absorbers, resins, reactive diluents, light stabilizers, plasticizers, non-reactive compounds, chain transfer agents, thermal polymerization initiators, anaerobic polymerization initiators, polymerization inhibitors, inorganic fillers, organic fillers, adhesion improvers such as coupling agents, thermal stabilizers, antibacterial and antifungal agents, flame retardants, matting agents, defoaming agents, leveling agents, wetting and dispersing agents, anti-settling agents, thickening and anti-sagging agents, color separation preventers, emulsifiers, slip and skid preventers, anti-blocking agents, desiccants, antifouling agents, antistatic agents, conductive agents (electrostatic aids), solvents and other components. These components may be used alone or in combination of two or more. These components can be appropriately selected from known ones for use. Also, the blending amounts of these can be set as appropriate.

[0188] Further, when the above sulfoxide-containing polymer composition is for optical materials, other components may be appropriately included according to the use of the optical materials. Specific examples of the above other components preferably include ultraviolet absorbers, IR cut agents, reactive diluents, pigments, dyes, antioxidants, light stabilizers, plasticizers, non-reactive compounds, defoaming agents and the like.

[0189] The sulfoxide-containing polymer composition preferably has a glass transition temperature (Tg) of 80 to 250°C. When the glass transition temperature is within the above range, molding processing can be easily performed. From the viewpoint of increasing heat resistance, the above glass transition temperature is more preferably 90°C or higher, still more preferably 100°C or higher, and from the viewpoint of easily performing molding processing, it is more preferably 200°C or lower. The above glass transition temperature can be determined by the same method as the method for measuring the glass transition temperature of the above-mentioned polymer.

[0190] The above sulfoxide-containing polymer composition preferably has a refractive index of 1.69 or more. When the refractive index is within the above range, it can be suitably applied as an optical material or the like. The above refractive index is more preferably 1.70 or more, and still more preferably 1.71 or more. The above refractive index can be determined by the same method as the method for measuring the refractive index of the polymer described above.

[0191] The above sulfoxide-containing polymer composition preferably has an Abbe number of 10 or more. When the Abbe number is within the above range, the light dispersion is small, and it can be an optical material suitable for lenses. The above Abbe number is more preferably 15 or more, still more preferably 18 or more, and even more preferably 20 or more. From the viewpoint of adjusting the light dispersibility, the above Abbe number is more preferably 60 or less, and still more preferably 55 or less. The above Abbe number can be determined by the same method as the method for measuring the Abbe number of the polymer described above.

[0192] The above sulfoxide-containing polymer composition preferably has a visible light transmittance of 70% or more. When the above visible light transmittance is within the above range, it can be suitably used for optical materials. The above visible light transmittance is more preferably 80% or more, still more preferably 85% or more, and even more preferably 88% or more. The above visible light transmittance is the parallel line transmittance, and can be determined by the same method as the method for measuring the visible light transmittance of the above sulfoxide-containing polymer.

[0193] The method for producing the above sulfoxide-containing polymer composition is not particularly limited, and it can be prepared by mixing the above sulfoxide-containing polymer, the above inorganic substance, and other components as necessary. Examples of the above mixing include known means such as bead mills, roll mills, ball mills, jet mills, kneaders, and blenders.

[0194] Further, the sulfoxide-containing polymer and the sulfoxide-containing polymer composition of the present invention are preferably thermoplastic. When they are thermoplastic, the molding process is easy and the productivity is excellent.

[0195] The sulfoxide-containing polymer and the sulfoxide-containing polymer composition of the present invention can also be suitably used as molding materials. The molding method is not particularly limited, and examples include methods generally known as processing methods for thermoplastic resins, such as injection molding, extrusion molding, T-die method, inflation method, etc. Further, it may be molded into a desired shape by a method such as a casting method or coating. The above shape is not particularly limited, and various known shapes such as lenses, sheets, and films can be mentioned.

[0196] 4. Applications The sulfoxide-containing polymer and the sulfoxide-containing polymer composition obtained by the production method of the present invention are suitably used for optical materials, opto-device members, display device members, etc. Specific examples of such applications include, for example, spectacle lenses, imaging lenses for cameras such as (digital) cameras, mobile phone cameras, in-vehicle cameras, etc., light beam condensing lenses, light diffusing lenses, etc., lens materials for LEDs, optical adhesives, optical bonding materials, optical transmission joining materials, filters, diffraction gratings, diffractive optical elements, prisms, optical waveguides, watch glasses, transparent glasses such as cover glasses for display devices, etc., and optical applications such as cover glasses; opto-device applications such as photosensors (optical sensors (CMOS sensors, TOF sensors, etc.)), photoswitches, LEDs, micro-LEDs, light-emitting elements, optical waveguides, multiplexers, demultiplexers, circuit breakers, optical splitters, optical fiber adhesives, etc.; display device applications such as substrates for display elements such as LCDs, organic ELs, PDPs, etc., substrates for color filters, substrates for touch panels, index matching materials used for touch panels, etc., display protective films, display backlights, light guide plates, anti-reflection films, anti-fogging films, light extraction improvers for LEDs, organic ELs, etc.

[0197] Among these, an imaging lens, a filter, a diffraction grating, a diffractive optical element, a prism, an optical waveguide, an LED, a micro-LED, a light-emitting element, a color filter, and a touch panel are more preferable. Further, the sulfoxide-containing polymer obtained by the production method of the present invention usually tends to have a wide region having no absorption in the visible region and the infrared region. Such a polymer is also preferably used as an optical material in the visible region and the infrared region.

[0198] The sulfoxide-containing polymer and the sulfoxide-containing polymer composition obtained by the production method of the present invention are used in various applications such as mechanical part materials, electrical and electronic part materials, automotive part materials, civil engineering and construction materials, molding materials, etc., as well as materials for paints and adhesives, etc., in addition to optical applications. For example, the sulfoxide-containing polymer obtained by the production method of the present invention usually tends to have excellent heat resistance, and such a polymer having excellent heat resistance can also be used for heat-resistant materials, ferroelectric materials, heat dissipation materials, separators for battery materials, filters such as gas separation membranes and liquid separation membranes, electrode materials for fuel cells, Li batteries, etc., and battery members such as electrolyte materials. Further, it can also be preferably used as an insulating material and an antenna material utilizing low dielectric properties.

[0199] The sulfoxide-containing polymer and the sulfoxide-containing polymer composition obtained by the production method of the present invention can be preferably used as molding materials. Examples of the molding method include molding using a mold or a resin mold such as a conventionally known injection molding, T-die method, inflation method, imprint molding, nanoimprint molding, etc. You may shape | mold into a desired shape by methods, such as a casting method and application | coating. The said shape is not specifically limited, A various well-known shape, such as a lens, a sheet | seat, and a film, is mentioned.

[0200] In addition, the sulfoxide-containing polymer and the sulfoxide-containing polymer composition obtained by the production method of the present invention can be suitably used for processing by an etching process such as conventionally known plasma etching and a resist process utilizing conventionally known solubility differences. Further, it can also be suitably used for coating by spin coating, bar coating, squeegee coating, inkjet coating, or the like. The composition containing the sulfoxide-containing polymer obtained by the production method of the present invention is preferably a thermoplastic resin composition in terms of good processability, and is preferably a curable resin composition in terms of low viscosity and good followability to a fine mold or resin mold during molding. As described above, the sulfoxide-containing polymer and the sulfoxide-containing polymer composition obtained by the production method of the present invention can be suitably used for a wide range of applications including optical applications.

Examples

[0201] Examples are given below to explain the present invention in more detail, but the present invention is not limited only to these examples. Unless otherwise specified, "parts" means "parts by mass" and "%" means "% by mass". The evaluation of each polymer obtained in the examples and comparative examples and the sulfide-containing polymer used in the examples was carried out according to the following methods.

[0202] <Measurement of heavy metal content> Using an ICP emission spectroscopic analyzer ICP-8100 (manufactured by Shimadzu Corporation), measurement was carried out under appropriate plasma conditions (high-frequency output 1.4 kW, coolant gas 20.0 L / min, plasma gas 1.40 L / min, carrier gas 0.60 L / min, plasma light source), and the heavy metal content (iron content) in the polymer was evaluated based on the calibration curve, and the heavy metal content (ppm) relative to the polymer was determined. As the measurement sample, a sample appropriately diluted with a solvent so that the polymer concentration was 0.1 to 10% by mass was used. As the solvent, N-methylpyrrolidone was used for the polymer whose main chain was not oxidized, and dimethylformamide was used for the polymer whose main chain was oxidized and the oxidation rate was 90% or more.

[0203] <Weight average molecular weight (Mw)> The weight average molecular weight of the polymer was determined by gel permeation chromatography (GPC) under the following conditions. Apparatus 1: SHIMAZU, CBM-20A. Apparatus 2: Agilent Technologies 1260 Infinity. Detector: Differential refractive index detector (RI) (SHIMAZU, SPD-20MA), and ultraviolet-visible-infrared spectrophotometer (SHIMAZU, SPD-20MA). Column: TOSOH, TSKgel SuperHM-N. Column temperature: 40 °C. Flow rate: 0.3 ml / min. Calibration curve: Polystyrene Standards. Eluent: Chloroform, tetrahydrofuran.

[0204] <MALDI (time-of-flight mass spectrometry)> The obtained polymer was subjected to MALDI measurement under the following conditions. Apparatus: Time-of-flight mass spectrometer (Bruker AutoflexIII) Sample preparation: Approximately 2 mg of the measurement sample was dissolved in 1.0 g of tetrahydrofuran, 20 mg of 2,5-dihydroxybenzoic acid as a matrix agent, and 2.0 mg of sodium iodide as an ionizing agent were dissolved, and the adjusted solution was applied to a measurement target plate and dried at room temperature for about 100 minutes.

[0205] < 1 H-NMR> The obtained polymer was subjected to 1 1H-NMR measurement under the following conditions. Apparatus: Nuclear magnetic resonance apparatus (400 MHz) manufactured by JEOL Ltd. Measurement solvent: deuterated dichloromethane, deuterated chloroform. Sample preparation: Several mg to several tens of mg of the obtained polymer was dissolved in the measurement solvent.

[0206] <ir> For the obtained polymer, IR measurement was carried out under the following conditions. Apparatus: Fourier transform infrared spectrophotometer (FT / IR-6100) manufactured by JASCO Sample preparation: About 2 mg of the sample was diluted with about 300 mg of dry potassium bromide (KBr). The mixture was ground with a mortar and pestle and molded.

[0207] <Elemental content ratio O / S ratio> Using a sample prepared by spin-coating 0.25 ml of the polymer solution onto a silicon wafer, a photoelectron spectrometer (JPS-9010TR, XPS apparatus, light source: Mg, X-ray output: 400 W) manufactured by JEOL was used to measure the peak intensity derived from the 2p orbital of sulfur atoms and the peak intensity derived from the 1s orbital of oxygen atoms, and the O / S ratio was calculated by calculating their integral ratio. If necessary, the peak intensity derived from the 1s orbital of carbon atoms was also measured, and the O / S ratio was calculated taking the result into account. The measurement method, the position of the binding energy, etc. were referred to the Handbook of X-ray Photoelectron Spectroscopy (JEOL, published in March 1991). For those in which the peaks of sulfide and sulfoxide could be separated by 1H-NMR measurement, the O / S ratio was calculated by calculating their respective integral ratios.

[0208] <Binding energy> Using a sample prepared by spin-coating 0.25 ml of the polymer solution onto a silicon wafer, a photoelectron spectrometer (JPS-9010TR, XPS apparatus) manufactured by JEOL was used to measure the binding energy from the peak position of the 2p3 / 2 orbital of sulfur atoms.

[0209] <Organic elemental analysis> For the obtained polymer, elemental analysis measurement was carried out with the following apparatus. Apparatus: J·Science·Lab JM10.

[0210] <Transmittance> (Sample preparation) Regarding the polymer to be subjected to the oxidation reaction in the examples (the sulfide-containing polymer obtained in the production examples), a solution in which the polymer was dissolved was prepared such that the concentration was 5% by mass in chloroform for the polymers obtained in the examples and comparative examples (the polymers after the oxidation reaction), and the concentration was 5% by mass in hexafluoro-2-propanol, respectively. The obtained solution was spin-coated on a glass substrate (manufactured by Matsunami Glass Industry Co., Ltd., S1111) that hardly absorbs visible light at about 500 rpm × 60 s and dried at 100 °C for 10 minutes to form a thin film (thickness 1 μm). (Measurement) The transmittance of the obtained thin film was measured using a spectrophotometer (Ultraviolet-Visible-Infrared Spectrophotometer V-700 series manufactured by JASCO Corporation). To evaluate the visible light transmittance, comparison was made at a transmittance of 400 nm. Air was used as a control sample. The above transmittance is the parallel-line transmittance.

[0211] [Transmittance after heating] The thin film used in the evaluation of the transmittance of the above thin film was heated at 260 °C for 10 minutes, and the transmittance was measured using the heated thin film as a sample. The measurement method and conditions were the same as those in the above <Transmittance of the thin film>.

[0212] (Synthesis of monomers) [Synthesis Example 1] To a 500 mL three-necked flask, water (98 mL), o-toluenethiol (2-methylbenzenethiol) (18.2 g, 0.147 mol), tetrabutylammonium iodide (54.3 mg, 0.147 mmol) were added, and further, 30% hydrogen peroxide solution (15.2 mL, 0.147 mol) was added dropwise at 1 mL / min and stirred at 60 °C for 2 hours. After cooling to room temperature, the supernatant (aqueous layer) was removed, then an aqueous sodium thiosulfate solution was added, and the mixture was stirred at room temperature for 2 hours, and the supernatant (aqueous layer) was removed. The reaction solid was filtered, washed in the order of pure water and methanol, and bis(2-methylphenyl) disulfide was recovered through vacuum drying. The yield was 98%. 1 H-NMR, 13 By means of 13C-NMR and FAB-MS, it was confirmed to be bis(2-methylphenyl) disulfide (2,2'-dimethyldiphenyl disulfide).

[0213] [Synthesis Example 2] A synthesis reaction was carried out under the same conditions as in Synthesis Example 1, except that the raw material in Synthesis Example 1 was changed to p-toluenethiol (4-methylbenzenethiol) instead of o-toluenethiol, and bis(4-methylphenyl) disulfide was obtained in a yield of 98%. 1 1H-NMR, 13 By means of 13C-NMR and FAB-MS, it was confirmed to be bis(4-methylphenyl) disulfide (4,4'-dimethyldiphenyl disulfide).

[0214] (Synthesis of sulfide-containing polymer) [Production Example 1] To a 500 mL three-necked flask, iron(III) chloride (6.05 g, 37.30 mmol), (+)-CSA (1.73 g, 7.46 mmol), and Na2S2O8 (1.78 g, 7.46 mmol) were added to diphenyl disulfide (131.00 g, 0.6 mol) and the bis(2-methylphenyl) disulfide (36.01 g, 0.15 mol) obtained in the above Synthesis Example 1, and oxidative polymerization was carried out by air bubbling (100 mL / min) and stirring the reaction solution at 160 °C for 40 hours. After cooling to room temperature, a polymer (Ps1) in the form of a black solid was obtained in a yield of 92%. Regarding the structure of the obtained polymer (Ps1), 1 It was identified by 1H-NMR, GPC, ICP, XPS, and MALDI. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.18 (m, 23H), 2.25 (m, 3H). The weight average molecular weight (Mw) was 2400. From ICP analysis, the iron content was 21500 ppm. From XPS measurement, peaks were observed at 160.3 - 164.9 eV, and by peak separation, the peaks could be separated into 160.3 - 164.9 eV (sulfide) and 163.5 - 164.9 eV (disulfide), and the peak area ratio of sulfide to disulfide was 93:7. Also, by MALDI measurement, repeating peaks of m / z 107.98 and m / z 122.04 were recognized, and it was confirmed that the polymer contains -C6H4S- and -C6H3(CH3)S- as component (A).

[0215] [Production Example 2] The monomer in Production Example 1 was changed to bis(4-methylphenyl) disulfide obtained in Synthesis Example 2 instead of bis(2-methylphenyl) disulfide, and the polymerization reaction was carried out under the same conditions as in Production Example 1 except that the reaction time was 60 hours, and a polymer (Ps2) was obtained in a yield of 94%. Regarding the structure of the obtained polymer (Ps2), 1 it was identified by 1H-NMR, GPC, ICP, XPS, and MALDI. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.20 (m, 23H), 2.25 (m, 3H). The weight average molecular weight was 3040. From ICP analysis, the iron content was 22500 ppm. From XPS measurement, peaks were observed at 160.1 - 164.8 eV, and by peak separation, the peaks could be separated into 160.1 - 164.8 eV (sulfide) and 163.5 - 164.8 eV (disulfide), and the peak area ratio of sulfide to disulfide was 95:5. Also, by MALDI measurement, repeating peaks of m / z 107.95 and m / z 122.02 were observed, and it was confirmed that the polymer contains -C6H4S- and -C6H3(CH3)S- as component (A).

[0216] [Example 1] In a 100 ml eggplant flask, 1.1 g of the polymer (Ps1) obtained in Production Example 1 and THF (1.0 M, 10 mL) as a solvent were added. After stirring for 10 minutes, 1.0 mL of pure water (THF: water = 10:1) was added and stirred for 5 minutes. Then, while cooling the eggplant flask in an ice bath, trichloroisocyanuric acid (TCCA) (0.369 g) was added and stirred for 2 hours. After completion of the reaction, methanol (40 mL) was gradually added to the reaction solution to precipitate the product, and the precipitate in the reaction solution was filtered through a Kiriyama filter and washed with methanol and pure water. Next, the obtained powder was vacuum dried at room temperature to obtain a polymer (Po1) powder. Regarding the structure of the obtained polymer (Po1), 1 It was identified by 1H-NMR, XPS, ICP, IR, and elemental analysis. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.19 (m, 15H) δ = 7.56 (m, 8H), 2.35 (m, 3H). From IR, peaks derived from sulfone were observed around 1350 cm -1 and around 1170 cm -1 and a peak derived from sulfoxide was observed around 1050 cm -1 . From elemental analysis, it was estimated that the polymer contained 1.35% chlorine atoms by weight ratio and the terminal structure was -S(=O2)Cl.

[0217] [Example 2] In a 100 ml eggplant flask, 1.1 g of the polymer (Ps2) obtained in Production Example 2 and THF (1.0 M, 10 mL) as a solvent were added. After stirring for 10 minutes, 1.0 mL of pure water (THF: water = 10:1) was added and stirred for 5 minutes. Then, while cooling the eggplant flask in an ice bath, TCCA (0.369 g) was added and stirred for 2 hours. After that, zinc powder (0.131 g) was added and stirred at room temperature for 16 hours. After completion of the reaction, methanol (40 mL) was gradually added to the reaction solution to precipitate the product, and the precipitate in the reaction solution was filtered through a Kiriyama filter and washed with methanol and pure water. Next, the obtained powder was vacuum dried at room temperature to obtain a polymer (Po2) powder. Regarding the structure of the obtained polymer (Po2), 1 It was identified by 1H-NMR, XPS, ICP, IR, and elemental analysis. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.19 (m, 9H), δ = 7.56 (m, 14H), 2.35 (m, 3H). From IR, a peak derived from mercapto was observed near 2570 cm -1 and the chlorine atom content in the polymer was below the detection limit by elemental analysis, confirming that the terminal structure was -SH.

[0218] [Example 3] Into a 100 mL eggplant flask, the polymer (Ps1) (1.1 g) obtained in Production Example 1 and THF (1.0 M, 10 mL) as a solvent were added. After stirring for 10 minutes, 0.5 mL of pure water was added and stirred for 5 minutes. Then, while cooling the eggplant flask in an ice bath, NaClO·5H2O (0.987 g) was added, concentrated hydrochloric acid (0.5 mL) was gradually added, and after stirring for 2 hours, zinc powder (0.131 g) was added and stirred at room temperature for 16 hours. After completion of the reaction, methanol (40 mL) was gradually added to the reaction solution to precipitate the product, and the precipitate in the reaction solution was filtered through a Kiriyama filter and washed with methanol and pure water. Then, the obtained powder was vacuum dried at room temperature to obtain a polymer (Po3) powder. Regarding the structure of the obtained polymer (Po3), 1 it was identified by 1H-NMR, XPS, ICP, and IR. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.19 (m, 7H), δ = 7.56 (m, 12H), 2.35 (m, 3H). From IR, a peak derived from mercapto was observed near 2570 cm -1 and it was confirmed that the terminal structure was -SH.

[0219] [Example 4] In a 100 mL eggplant flask, the polymer (Ps1) obtained in Production Example 1 (1.1 g) and THF (1.0 M, 10 mL) as a solvent were added. After stirring for 10 minutes, 1.0 mL of pure water (THF: water = 10:1) was added and stirred for 5 minutes. Next, while cooling the eggplant flask in an ice bath, TCCA (0.369 g) was added. After stirring for 2 hours, triethylamine (TEA) (0.506 g) was added and stirred at room temperature for 30 minutes. Further, 1 mL of aqueous ammonia (25%) as the introduced amine was added and stirred for 2 hours. After completion of the reaction, the product was precipitated by gradually adding 5% hydrochloric acid in methanol (40 mL) to the reaction solution. The precipitate in the reaction solution was filtered through Kiriyama filter and washed with methanol and pure water. Next, the obtained powder was vacuum dried at room temperature to obtain a polymer (Po4) powder. Regarding the structure of the obtained polymer (Po4), 1 It was identified by 1H-NMR, XPS, ICP, and elemental analysis. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.19 (m, 5H) δ = 7.56 (m, 14H), 2.35 (m, 3H). From XPS measurement, peaks were observed at 160.5 - 168.8 eV. By peak separation, peaks could be separated into 160.5 - 163.8 eV (sulfide), 160.9 - 168.8 eV (sulfoxide), and 166.0 - 168.8 eV (sulfone). The peak area ratio of sulfide, sulfoxide, and sulfone was 22:72:6. It was confirmed by elemental analysis that the chlorine atom content in the polymer was below the detection limit and the nitrogen atom content was 0.77%, and it was confirmed that the terminal structure was -S(=O2)NH2.

[0220] [Example 5] Into a 100 ml eggplant flask, the polymer (Ps2) (1.1 g) obtained in Production Example 2 and THF (1.0 M, 10 mL) as a solvent were added. After stirring for 10 minutes, 1.0 mL of pure water (THF: water = 10:1) was added and stirred for 5 minutes. Next, while cooling the eggplant flask in an ice-cooled bath, TCCA (0.369 g) was added. After stirring for 2 hours, zinc powder (0.131 g) was added and stirred at room temperature for 30 minutes. Further, acrylic acid (AA) (0.144 g) was added dropwise as an alkyne reactant for the enethiol reaction and stirred for 16 hours. After completion of the reaction, methanol (40 mL) was gradually added to the reaction solution to precipitate the product, and the precipitate in the reaction solution was filtered through a Kiriyama filter and washed with methanol and pure water. Next, the obtained powder was dried in vacuo at room temperature to obtain a polymer (Po5) powder. Regarding the structure of the obtained polymer (Po5), 1 It was identified by 1H-NMR, XPS, ICP, and IR. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.19 (m, 29H) δ = 7.56 (m, 32H), 2.35 (m, 8H), 2.52 (m, 2H), 3.11 (m, 2H). From IR, a peak derived from a carboxy group was observed near 1690 cm -1 and it was confirmed that the terminal structure was -SCH2CH2COOH.

[0221] [Example 6] Into a 100 ml eggplant flask, the polymer (Ps1) (1.1 g) obtained in Production Example 1 and THF (1.0 M, 10 mL) as a solvent were added. After stirring for 10 minutes, 1.0 mL of pure water (THF: water = 10:1) was added and stirred for 5 minutes. Next, while cooling the eggplant flask in an ice-cooled bath, TCCA (0.369 g) was added. After stirring for 2 hours, 10 mL of NMP was added as a solvent, and then K2CO3 (0.691 g) was added and stirred at room temperature for 30 minutes. After stirring, diallylamine (DAA) was added dropwise as an amine and stirred at room temperature for 16 hours. After completion of the reaction, 5% hydrochloric acid-methanol (40 mL) was gradually added to the reaction solution to precipitate the product, and the precipitate in the reaction solution was filtered through a Kiriyama filter and washed with methanol and pure water. Next, the obtained powder was dried in vacuo at room temperature to obtain a polymer (Po6) powder. Regarding the structure of the obtained polymer (Po6), 1 It was identified by 1H-NMR, XPS, ICP, IR, and elemental analysis. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.19 (m, 35H) δ = 7.56 (m, 26H), 2.35 (m, 8H), 3.81 (m, 4H), 5.09 (m, 4H), 5.57 (m, 2H). From IR, a peak derived from an allyl group was observed near 990 cm -1 and peaks derived from sulfone were observed near 1350 cm -1 and 1170 cm -1 and a peak derived from sulfoxide was observed near 1050 cm -1 It was confirmed by elemental analysis that the chlorine atom content in the polymer was below the detection limit and the nitrogen atom content was 0.48%, and that a part of the terminal structure was -S(=O2)N(CH2CH=CH2)2.

[0222] [Example 7] To a 100 mL eggplant flask, the polymer (Ps1) (1.1 g) obtained in Production Example 1 and THF (1.0 M, 10 mL) as a solvent were added. After stirring for 10 minutes, 1.0 mL of pure water (THF: water = 10:1) was added and stirred for 5 minutes. Next, while cooling the eggplant flask in an ice bath, TCCA (1.38 g) was added and stirred for 2 hours. Further, 1 mL of aqueous ammonia (25%) was added and stirred for 2 hours. After completion of the reaction, the product was precipitated by gradually adding 5% hydrochloric acid in methanol (40 mL) to the reaction solution. The precipitate in the reaction solution was filtered through Kiriyama filter and washed with methanol and pure water. Next, the obtained powder was vacuum dried at room temperature to obtain a polymer (Po7) powder. Regarding the structure of the obtained polymer (Po7), 1 It was identified by 1H-NMR, XPS, ICP, and elemental analysis. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.56 (m, 19H), 2.35 (m, 3H). From XPS measurement, peaks were observed at 160.8 - 168.9 eV. By peak separation, peaks could be separated into 160.8 - 163.6 eV (sulfide), 160.8 - 168.9 eV (sulfoxide), and 166.0 - 168.9 eV (sulfone). The peak area ratio of sulfide, sulfoxide, and sulfone was 2:92:6. Elemental analysis confirmed that the chlorine atom content in the polymer was below the detection limit and the nitrogen atom content was 0.80%. It was confirmed that a part of the terminal structure was -S(=O2)NH2.

[0223] [Comparative Example 1] In a 50 ml eggplant flask, 0.33 g of the polymer (Ps1) obtained in Production Example 1 was added and dissolved in 3.0 mL of chloroform. Then, 65% meta-chloroperbenzoic acid (mCPBA) (0.796 g) was gradually added to the eggplant flask and stirred at room temperature for 16 hours. Thereafter, the reaction solution was dropped into 20 mL of hydrochloric acid-acidic methanol solution to precipitate the oxidized product. After filtering the precipitate through Kiriyama filter, it was washed with methanol and water in that order and dried in vacuo to obtain a brown polymer (PoC1). The structure of the obtained polymer (PoC1) was 1 identified by 1H-NMR, XPS, and ICP. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.56 (m, 19H), 2.35 (m, 3H). From XPS measurement, peaks were observed at 161.8 - 168.5 eV. By peak separation, peaks could be separated into 161.8 - 168.5 eV (sulfoxide) and 161.8 - 163.5 eV (sulfide). The peak area of sulfoxide and sulfide was 97:3.

[0224] [Comparative Example 2] In a 300 ml eggplant flask, 6.73 g of the polymer (Ps1) obtained in Production Example 1 was added and dissolved in 60.9 mL of cyclopentyl methyl ether (CPME) at 70 °C. To the obtained polymer solution, a solution prepared by adding 66.7 mg of 1,1,1-trifluoroacetone to 6.12 mL of 60% hydrogen peroxide solution was added, and the mixture was stirred at 60 °C for 18 hours. To the polymer solution after stirring, a mixed solvent of 122 mL of methanol and 122 mL of water was added. After filtering the solid, it was washed with water and methanol and then dried under vacuum to obtain a brown polymer (PoC2). The structure of the obtained polymer (PoC2) was 1 identified by 1H-NMR, XPS, and ICP. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.56 (m, 19H), 2.35 (m, 3H),... Peaks were observed at 161.2 - 168.9 eV, and by peak separation, the peaks could be separated into 161.2 - 168.9 eV (sulfoxide) and 161.2 - 163.8 eV (sulfide). The peak area ratio of sulfoxide to sulfide was 96:4.

[0225] [Comparative Example 3] In a 50 mL eggplant flask, 1.10 g of the polymer (Ps1) obtained in Production Example 1 was added, dissolved in a mixed solvent of 10 mL of tetrahydrofuran and 0.5 mL of methanol, sodium borohydride (0.151 g) was added, and the mixture was stirred at room temperature for 6 hours. After stirring, the solvent was removed under reduced pressure. Next, 10 mL of cyclopentyl methyl ether (CPME) was added and dissolved at 70 °C. To the obtained polymer solution, a solution prepared by adding 12.3 mg of 1,1,1-trifluoroacetone to 0.030 mL of 60% hydrogen peroxide solution was added, and the mixture was stirred at 60 °C for 18 hours. The polymer solution after stirring was dropped into 400 mL of a 3% hydrochloric acid-methanol solution to precipitate, and after filtering the solid, it was washed with water and methanol and then dried under vacuum to obtain a polymer (PoC3). The structure of the obtained polymer (PoC3) was 1 identified by 1H-NMR, XPS, and ICP. As a result, 1 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.19 (m, 13H) δ = 7.56 (m, 6H), 2.35 (m, 3H). From XPS measurement, peaks were observed at 160.3 - 168.1 eV, and by peak separation, the peaks could be separated into 160.3 - 167.8 eV (sulfide) and 164.6 - 167.8 eV (sulfoxide). The peak area ratio of sulfoxide to sulfide was 30:70.

[0226] [Comparative Example 4] In a 50 mL eggplant flask, 1.10 g of the polymer (Ps1) obtained in Production Example 1 was added, dissolved in a mixed solvent of 10 mL of tetrahydrofuran and 0.5 mL of methanol, sodium borohydride (0.151 g) was added, and the mixture was stirred at room temperature for 6 hours. After stirring, 1 mL of a hydrochloric acid-methanol solution was added dropwise and stirred for 30 minutes. The polymer solution after stirring was precipitated by dropping it into 400 mL of a 3% hydrochloric acid-methanol solution, and the solid was filtered, washed with water and methanol, and dried under vacuum to obtain a polymer (PoC4). The structure of the obtained polymer (PoC4) was identified by 1H-NMR, XPS, ICP, and IR. As a result, 1H-NMR (CD2Cl2, 400 MHz, ppm): δ = 7.19 (m, 19H), 2.35 (m, 3H). From XPS measurement, only a peak of 160.1 - 163.7 eV (sulfide) was observed. From IR, a peak derived from a mercapto group was observed near 2570 cm -1 and it was confirmed that the terminal structure was -SH.

[0227] The evaluation results of the polymers (Po1) to (Po7), (PoC1) to (PoC4) obtained in Examples 1 to 7 and Comparative Examples 1 to 4 are shown in Table 1. From Table 1, the polymers obtained in the comparative examples had a low transmittance after heating, while all of the polymers obtained in the examples had a high transmittance after heating.

[0228] [Table 1]

[0229] < / ir>

Claims

Claim 1 A method for producing a sulfur-containing polymer having a sulfoxide skeleton in the main chain, comprising: an oxidation step of oxidizing a sulfur-containing polymer having a sulfide skeleton in the main chain in a mixed solvent of an organic solvent and water using at least one compound selected from the group consisting of hypochlorous acid, hypochlorite, and a compound capable of generating hypochlorous acid The method for producing a sulfur-containing polymer, characterized by the above. Claim 2 The method for producing a sulfur-containing polymer according to claim 1, further comprising a polymer terminal control step. Claim 3 The method for producing a sulfur-containing polymer according to claim 2, wherein the polymer terminal control step uses a reducing substance or a basic substance. Claim 4 The method for producing a sulfur-containing polymer according to any one of claims 1 to 3, further comprising a polymerization step of polymerizing a monomer component containing a sulfur-containing monomer to obtain a sulfur-containing polymer having a sulfide skeleton in the main chain.

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