WO1998022217A1

WO1998022217A1 - Polymeric material for water treatment, cation-exchange resin, and anion-exchange resin

Info

Publication number: WO1998022217A1
Application number: PCT/JP1997/004189
Authority: WO
Inventors: Masa-Aki Wakita; Masato Yamaguchi; Tsuneyasu Adachi; Toshihiro Ueno
Original assignee: Kurita Water Industries Ltd.
Priority date: 1996-11-18
Filing date: 1997-11-18
Publication date: 1998-05-28

Abstract

A polymeric material which has such a high resistance to oxidative decomposition that it is less apt to suffer the performance decrease caused by oxidative deterioration and to cause water pollution by oxidative decomposition products during its use, and which is usable for water treatment as a coagulant, dehydrant, dispersant, film, etc.; a cation-exchange resin which has an excellent resistance to oxidative decomposition and is reduced in the elution of resin components during use; and an anion-exchange resin which has an excellent resistance to oxidative decomposition and is reduced in the elution of resin components during use. The polymeric material is characterized by having groups which have an antioxidant function and have been covalently bonded. The cation-exchange resin is characterized in that the groups having an antioxidant function have been covalently bonded through sulfonamide bonds represented by the general formula (1): -SO2NR1-. The anion-exchange resin is characterized in that the groups having an antioxidant function have been covalently bonded through iminoalkylene bonds represented by the general formula (2): -(CH¿2)nNR?2-. In the formulae, R?1 and R2¿ each represents hydrogen or methyl and n is an integer of 1 to 4.

Description

Description Polymer water treatment material, force exchange resin and anion exchange resin

The present invention relates to a polymer water treatment material, a cation exchange resin, and an anion exchange resin. More specifically, the present invention relates to a coagulant, a dehydrating agent, and a dispersing agent, in which a group having an antioxidant function is covalently bonded, and there is little risk of deterioration in performance due to oxidative deterioration and contamination of water quality due to oxidative decomposition products during use. Polymer water treatment material that can be used for water treatment as a membrane, etc., cation exchange resin with excellent resistance to oxidative decomposition and less elution of resin components, and anion with excellent resistance to oxidative decomposition and less elution of resin components Regarding exchange resin. Background art

For water treatment, polymer materials such as ion exchange resins, flocculants, dehydrating agents, dispersants, and membranes are used. These are mostly organic macromolecules. For example, an ion exchange resin has a structure in which an ion exchange group such as a sulfonic acid group or a trimethylammonium group is bonded to a polymer matrix having a three-dimensional network structure represented by a styrene-divinylbenzene copolymer. It is an insoluble solid acid or solid base that has been widely used in the production of ultrapure water used in the manufacture of semiconductors and pharmaceuticals, and in the condensate treatment of nuclear power plants. The flocculant, dehydrating agent, and dispersant include monomers having a carboxyl group such as acrylamide, acrylic acid, and methacrylic acid, 2-acrylamide 2-methylpropanesulfonic acid, vinylsulfonic acid, and styrenesulfonic acid. Homopolymers or copolymers of monomers having a sulfonic acid group, such as dialkylaminoalkyl acrylates and dialkylaminoalkyl methacrylates, etc .; A modified polymer having a structure or the like, a natural polymer such as chitosan, starch or the like, or a modified product thereof is used. As the membrane, cellulose acetate, polyimide, polyamide, High molecular compounds such as polysulfone are used.

Organic polymers generally undergo oxidative decomposition gradually in the presence of oxygen. The conventional polymer water treatment material ion exchange resin has the following problems caused by oxidative decomposition. For example, when ion-exchange resins and membranes are used in the production of ultrapure water used in semiconductor and pharmaceutical manufacturing, if the ion-exchange resins and membranes are oxidized and decomposed to elute constituent components, the quality of treated water will decrease. Occur. Oxidative degradation products such as sulfobenzoic acid, phenolsulfonic acid, and styrenesulfonic acid polymers are eluted from the strongly acidic cation exchange resin in which sulfonic acid groups are introduced into styrene divinylbenzene crosslinked copolymer particles. . These effluents not only degrade the quality of the treated water, but also decompose during heat exchange of the condensate to produce corrosive sulfate ions. It also contaminates the anion exchange resin, which is often used simultaneously. Styrene divinylbenzene cross-linked copolymer Decomposition products such as etc. are eluted, similarly deteriorating the treated water quality and contaminating the cation exchange resin often used at the same time. In addition, as the oxidative decomposition of the ion exchange resin proceeds, the ion exchange resin itself deteriorates.

Coagulants and dehydrating agents are added to wastewater and sludge as aqueous solutions to coagulate suspended solids and perform solid-liquid separation.However, the coagulant effect of coagulants and dispersants is greatly affected by their molecular weight, so oxidation When the molecular weight is reduced by decomposition, the performance is significantly reduced. That is, in the case of the polymer water treatment material, there is a problem that even if the oxidative decomposition is slight, the function is lowered or the water quality is lowered.

In order to avoid such problems, studies have been made from three viewpoints: the method of using the polymer water treatment material, the chemical structure, and the blending of auxiliaries for the purpose of stabilization. For example, Japanese Unexamined Patent Publications Nos. 62-132585 and JP-A-11-71645 disclose that ion exchange resin is sufficiently washed prior to use to reduce elution. A method for doing so is disclosed. In addition, JP-A-1-1191345 and JP-A-2-91946 disclose that an ion-exchange resin is stored in a low-dissolved oxygen concentration water or oxygen-free atmosphere, There is disclosed a method of avoiding contact with oxygen by lowering the dissolved oxygen concentration of an elephant fluid and passing the solution. However, high-molecular-weight water treatment materials and ion-exchange resins are gradually decomposed even by a small amount of oxygen, so even if these methods can reduce the initial amount of eluted substances, they will cause long-term oxidative decomposition. It is difficult to control. In order to avoid contact with oxygen, a special device for degassing a large amount of water is required.

On the other hand, Japanese Patent Publication No. 40-239398, Japanese Patent Application Laid-Open No. 59-122520, Japanese Patent Publication No. 61-1855507, Japanese Patent Application — 1 5 3 5 4 1 and Japanese Patent Laid-Open No. 58 — 16 3 4 4 5 discloses the oxidation of polyphenylene ether, fluorine-containing polymers, polyimides, polyamideimides, etc. A method for preparing a polymer water treatment material or an ion exchanger from a special material having a chemical structure that is difficult to receive is disclosed. However, these materials are not only more expensive than conventional polymer water treatment materials and ion exchangers, but also have problems in that it is difficult to control the shape and porosity of the product.

Regarding the blending of auxiliaries for the purpose of stabilization, Japanese Patent No. 25174111 discloses a method of suppressing oxidation by bringing a cation exchange resin into contact with an antioxidant and incorporating the antioxidant. ing. In addition, Japanese Patent Publication No. 491-27622, Japanese Patent Publication No. 52-272, and Japanese Patent Publication No. 58-47414 include acrylamide-based polymers. A stabilization method is disclosed by blending thiourea, formic acid, ammonia, potassium iodide, and 2-mercaptobenzoimidazole. However, in these methods, the auxiliary compounded for stabilization is physically incorporated or mixed, so that the auxiliary compound is eluted into the treated water. is there. INDUSTRIAL APPLICABILITY The present invention has excellent resistance to oxidative decomposition, and is less likely to cause deterioration in performance due to oxidative degradation during use and to cause contamination of water quality due to oxidized decomposed substances, and is used in water treatment as a coagulant, a dehydrating agent, a dispersant, a membrane, etc. Polymer water treatment materials that can be used, cation exchange resin with excellent resistance to oxidative decomposition and low elution of resin components during use, and anion exchange with excellent resistance to oxidative decomposition and low elution of resin components during use The purpose was to provide resin. Disclosure of the invention

The present inventors have conducted intensive studies to solve the above problems, and as a result, oxidative decomposition of the polymer water treatment material has already occurred in some parts immediately after synthesis, and oxidative decomposition even under ordinary storage or use conditions. Gradually progresses, and by covalently bonding a group having an antioxidant function to the polymer matrix of the polymer water treatment material, the antioxidant is simply mixed and impregnated or bonded by ionic bonds. It is more stable against oxidation than the ones that have been made, and it has been found that the performance is stably maintained for a long time as a polymer water treatment material or ion exchange resin. However, they found that they can be stably covalently bonded via a sulfonamide bond in a cation exchange resin and via an iminoalkylene bond in an anion exchange resin. ItaruTsuta based L, Te to the completion of the present invention to knowledge.

That is, the present invention

(1) a polymer water treatment material, wherein a group having an antioxidant function is covalently bonded;

(2) The group having an antioxidant function is a hindered amine group, a monocyclic or polycyclic hindered phenol group, a thioester group, a thioether group, an amine group, a phosphorus group, a benzophenone group, a salicylate group or a triazole group. (1) the polymer water treatment material according to the above,

(3) a cation exchange resin, wherein a group having an antioxidant function is covalently bonded through a sulfonamide bond represented by the general formula [1]:

-SOzNR ^1- … [1]

(Wherein, R ¹ is hydrogen or a methyl group.)

(4) The cation exchange resin according to (3), wherein the group having an antioxidant function is a hindered amine group or a hindered phenol group.

(5) An anion exchange resin, wherein a group having an antioxidant function is covalently bonded via an iminoalkylene bond represented by the general formula [2]:

One (CH ₂ ) nNR ² —… [2] (Wherein, R ² is hydrogen or a methyl group, and n is an integer of 1 to 4.), and

(6) The anion-exchange resin according to (5), wherein the group having an antioxidant function is a hindered phenol group or a hindered phenol group.

Is provided.

Further, as a preferred embodiment of the present invention,

(7) The polymer water treatment material according to item (1) or (2), wherein the group having an antioxidant function is bonded to 0.01 to 10 mol% of the monomer units constituting the polymer. ,

(8) The polymer water according to (1), (2) or (7), wherein the group having an antioxidant function is a 2,2,6,6-tetramethyl-4-piperidinyl group. Processing materials,

(9) Item (8), wherein the 2,2,6,6-tetramethyl-4-piperidinyl group is bonded by copolymerization of 2,2,6,6-tetramethyl-4-piperidinyl methacrylate. Polymer water treatment materials,

Can be mentioned. BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 is a graph showing the change over time in the amount of eluted material from the cation exchange resin. _C The best mode for carrying out the invention

In the polymer water treatment material of the present invention, the group having an antioxidant function introduced by a covalent bond is not particularly limited. For example, 2,2,6,6-tetramethyl-4-piperidine, 1,2,2 Hindered amines such as 2,6,6-pentamethyl-1-piperidine, monocyclic phenols such as 2,6-di-t-butyl-1-p-cresol, tetrakis [methylene-1- (3 ' Polycyclic phenols such as, 5'-di-t-butyl-4'-hydroxyphenylpropionate] methane, bis [2-methyl-1- (3-n-alkylthiopropionyloxy)- thioesters such as [t-butyl phenyl] sulfide; thioethers such as dilauryl thiodipropionate; phenyl-α-naphthylamine; N, N'-diphenyl ρ_phenylene Phosphorus antioxidants such as amines such as diamine, triphenylphosphite and tris (nonylphenyl) phosphite, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, etc. Salicylates such as benzophenone, phenyl salicylate, p-t-butylphenyl salicylate, bis (2,2,6,6-tetramethyl-4-piperidinyl) sebacate, bis (1 Hindered amide-based light stabilizers such as 1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, and triazole-based heavy metals such as 3- (N-salicyloyl) amine 1,2,4-triazole Examples include groups derived from compounds having an antioxidant function, such as blocking agents.

In the polymer water treatment material of the present invention, the amount of the group having an antioxidant function that is covalently bonded is not particularly limited. It is preferably 10 mol%, more preferably 0.01 to 8 mol%, and still more preferably 0.01 to 7 mol%. If the bonding amount of the group having an antioxidant function is less than 0.01 mol% of the monomer unit, the polymer water treatment material may not be provided with sufficient oxidation stability. The amount of binding of the group having an antioxidant function is usually 10 mol% is sufficient. The amount of groups attached decreases, and in many cases, it is economically disadvantageous.

In the polymer water treatment material of the present invention, a method of covalently bonding a group having an antioxidant function is not particularly limited. For example, a method of reacting a compound having an antioxidant function with a polymer water treatment material to form a polymer water A group having an antioxidant function can be covalently bonded to the treatment material, and after copolymerizing a monomer having an antioxidant function with another monomer, a functional group having a water treatment function is introduced by reaction. Alternatively, a polymer water treatment material in which a group having an antioxidant function is covalently bonded by copolymerization of a monomer having an antioxidant function and a monomer having a water treatment function can be obtained. . Examples of the monomer having an antioxidant function include a monomer having an antioxidant function and a monomer for addition polymerization having an unsaturated bond, and a structure having an antioxidant function and two functional groups having condensation reactivity. Condensation polymerization monomer having the above structure with antioxidant function is ring-opening polymerizable Ring-opening polymerization monomers bonded to the structure can be exemplified. Among these methods, there is a method of copolymerizing a monomer for addition polymerization having a structure having an antioxidant function and an unsaturated bond with or without a water treatment function and a monomer for addition polymerization. Synthesis is easy and preferred.

Examples of the monomer for addition polymerization having a structure having an antioxidant function and an unsaturated bond include, for example, 1,2,2,6,6, -pentanomethyl-4-piperidinyl methacrylate [Asahi Denka Kogyo Co., Ltd. ), Adekastab LA-82], 2,2,6,6-tetramethyl-14-piperidinyl methacrylate [Asahi Denka Kogyo Co., Ltd., Adekastab LA-87], etc. , 2-t-butyl-4-methyl-6- (2'-hydroxy-13'-t-butyl-15'-methylbenzinole) phenylacrylate [Sumitomo Chemical Co., Ltd., Sumilizer-GM], 2- [1- ( 2'-Hydroxy-3 ', 5'-di-t-pentylphenyl) ethyl] —4,6-di-t-pentylphenyl acrylate [Sumitomo Chemical Co., Ltd., hindered phenols such as Sumilizer-GS] Monomers having a structure are commercially available.

Also, hindered drugs such as 2,6-di-t-butyl-14-vinylphenol and derivatives thereof described in Makromol. Chem., Vol. 181, p. 557 (1980). Monomers having a phenol structure, 4-aryloxy 2,2,6,6-tetramethyl, described in J. Polymer Science: Part A, Vol. 32, page 961 (1994). Biperidine and its derivatives, 4-[(bicyclo [2.2.1] hept-5-en-1-ynole) methoxy] -1,2,2,6,6-tetramethylpiperidine and its derivatives, J. Applied N—4 ′ — (2 ′, 2 ′, 6 ′, 6′—tetramethylpiperidinyl) 1-2— described in P o 1 symbol Science, vol. 61, p. 1405 (1996). Monomers having a hindered amine structure, such as hydroxy-3-aryloxypropylamine, are described in Polymethyl Journal, Vol. 28, p. 827 (1996), 3- (3 ', Five A monomer having a hindered phenol structure such as'di-t-butyl-4'-hydroxyphenyl) propyl methacrylate may be used. In addition to these, known antioxidants such as hindered amine, monocyclic or polycyclic hindered phenol, thioester, thioether, amine, phosphorus, benzophenone, salicylate, triazole, etc. Monomer into which polymerizable group having unsaturated bond such as vinyl group, aryl group, styryl group, acryloyl group, methacryloyl group, N-vinylamino group, N-arylamino group, acrylamide group, methacrylamide group is introduced. Etc. can be used. In addition, these known antioxidants have a polymerizable group capable of undergoing polycondensation or ring-opening polymerization, for example, an amino group, a carboxyl group, a hydroxyl group, ethylene oxide, / 3-propiolactone, and / 3-pro- Monomers having a structure such as piolactam or ε-force prolactam can be used.

There is no particular limitation on the method of copolymerizing these monomers having an antioxidant function. Depending on the properties of each monomer and the properties of other monomers to be copolymerized, radical polymerization and cationic polymerization may be used. Polymerization methods such as addition polymerization such as anion polymerization and condensation polymerization and ring-opening polymerization can be appropriately selected.

The method for covalently bonding a group having an antioxidant function to a polymer water treatment material having no antioxidant function is not particularly limited. For example, a functional group such as a hydroxyl group, an amino group, a carboxyl group, or a halogenated alkyl group may be used. The high-molecular-weight water treatment material and an antioxidant capable of forming a covalent bond by reacting with these functional groups can be reacted. If the high molecular weight water treatment material does not have an appropriate functional group, it can react with an antioxidant after introducing an appropriate functional group, or can be combined with an antioxidant having an appropriate functional group and a polymer water treatment. Can react with the material.

In the cation exchange resin of the present invention, a group having an antioxidant function is covalently bonded via a sulfonamide bond represented by the general formula [1].

-SO z NR ^1- … [1]

However, in the formula, R ¹ is hydrogen or a methyl group.

The method for producing the cation exchange resin of the present invention is not particularly limited. For example, a chlorosulfone group and a sulfonate group are introduced into an insoluble carrier made of a polymer having a three-dimensional network structure, Compounds with groups with antioxidant function It can be produced by reacting with a methyl sulfone group.

The structure, shape, and manufacturing method of the insoluble carrier made of a polymer having a three-dimensional network structure are not particularly limited, and examples thereof include organic polymers such as a copolymer of styrene and divinylbenzene, a cross-linked polyethylene, and a cross-linked polypropylene. Insoluble carriers such as spheres, membranes, and fibers can be used. Crosslinked particles made of a styrene-divinylbenzene copolymer are obtained by dispersing styrene and divinylbenzene in water containing a dispersant such as polyvinyl alcohol, polyvinylpyrrolidone, and calcium phosphate. Such a radical polymerization initiator can be obtained by adding the radical polymerization initiator, and heating and stirring to carry out suspension polymerization. Although the ratio of styrene to divinyl benzene is not particularly limited, it is usually preferable that the content of divinyl benzene is 6 to 20% by weight, more preferably 8 to 12% by weight.

In the present invention, the method of introducing a group having an antioxidant function into a cation exchange resin via a sulfonamide bond is not particularly limited. For example, a chlorosulfone group is introduced into an insoluble carrier, and a primary or secondary amino group is further introduced. It can be easily introduced by reacting a group with a compound having a group having an antioxidant function. For example, by reacting chlorosulfonic acid, sulfonol chloride, a mixture of sulfur dioxide and chlorine, etc. with the styrenedivinylbenzene crosslinked copolymer particles, a ketone sulfone group can be easily introduced into the styrenedivinylbenzene crosslinked copolymer particles. can do. At this time, the reaction can be promoted by using a solvent that swells the styrene-divinylbenzene crosslinked copolymer particles such as tetrachloroethane and dichloromethane. Usually, the chlorosulfonating agent is preferably used in an amount equal to or more than the amount to be introduced.In the case of styrene-divinylbenzene crosslinked copolymer particles, use 2 to 3 times the benzene ring in the particles. Is preferred. There is no particular limitation on the temperature and time for the sulphonation reaction. For example, the reaction can be carried out by immersing in an ice-water bath or stirring at room temperature for several hours. After completion of the chlorosulfonation reaction, the reaction mixture is preferably filtered and washed with a solvent that does not react with chlorosulfone groups, such as chloroform, dichloromethane, and acetone.

Styrene divinylbenzene cross-linked copolymer particles with chlorosulfone groups introduced Is dispersed in a solvent such as chloroform and dichloromethane, and reacted with a compound having a primary or secondary amino group and a group having an antioxidant function to form a group having an antioxidant function through a sulfonamide bond. They can be covalently bonded. Examples of the compound having a primary or secondary amino group and a group having an antioxidant function include, for example,

Hindered amide compounds such as 4-amino-2,2,6,6-tetramethylpiperidine, 4-amino-1,2,2,6,6-pentamethylpiperidine, and 2,6-di-t— Butyl-4-aminomethylphenol, 2,6-di-t-butyl-4-methylethylaminophenol, 2,6-di-t-butyl-4-aminophenol, 2, Hindered phenolic compounds such as 6-di-t-butyl-14-aminopropylphenol and the like can be mentioned. The amount of the group having an antioxidant function to be introduced is not particularly limited, but is usually preferably from 0.01 to 10% by weight of the cation exchange resin. When a base such as trimethylamine or pyridine coexists during the reaction, hydrochloric acid generated by the reaction can be neutralized, and the reaction can proceed efficiently. The reaction temperature and time are not particularly limited, but usually the reaction can be terminated by stirring at room temperature for several hours.

Finally, the remaining chlorosulfone group is converted to a sulfone group by hydrolysis, whereby the cation exchange resin of the present invention can be obtained. The hydrolysis method is not particularly limited. For example, a product obtained by reacting a compound having an amino group and a group having an antioxidant function can be dispersed in water to perform a hydrolysis reaction. The hydrolysis reaction usually proceeds efficiently by heating at 40 to 50 ° C. In addition, as the hydrolysis proceeds, hydrochloric acid is generated to lower the pH of the system.To prevent the decomposition of the sulfonamide bond, a compound having a buffering action, such as sodium acetate, may be coexistent, or hydroxylated. It is preferable to add an alkali such as sodium to prevent the system from becoming strongly acidic.

In the cation exchange resin of the present invention, since a group having an antioxidant function is introduced by a covalent bond, the antioxidant is more oxidatively prevented than a conventional method in which an antioxidant is ionically adsorbed or physically retained. Prevents the agent from falling off, maintains excellent antioxidant properties over a long period of time, and effectively prevents the elution of resin components during use Can be.

The anion exchange resin of the present invention is a resin in which a group having an antioxidant function is covalently bonded via an iminoalkylene bond represented by the general formula [2].

-(CH ₂ ) nN R ^2- … [2]

Here, in the formula, R ² is hydrogen or a methyl group, and n is an integer of 1 to 4.

The method for producing the anion exchange resin of the present invention is not particularly limited. For example, a halogenated alkyl group is introduced into an insoluble carrier made of a polymer having a three-dimensional network structure, and a part of the halogenated alkyl group is amino. A group having an antioxidant function is introduced by reacting the group with a compound having an antioxidant function, and an amine is reacted with the remaining alkyl halide group to form a quaternary ammonium group. Can be manufactured. Alternatively, an alkyl halide group is introduced into an insoluble carrier made of a polymer having a three-dimensional network structure, and most of the alkyl halide group is reacted with an amine to form a quaternary ammonium group, and the remaining halogen is added. It can also be produced by introducing a group having an antioxidant function by reacting a compound having an amino group with an antioxidant function with an alkyl group.

In the present invention, the structure, shape, and production method of the insoluble carrier comprising a polymer having a three-dimensional network structure are not particularly limited, and examples thereof include organic polymers such as a copolymer of styrene and divinylbenzene, a crosslinked polyethylene, and a crosslinked polypropylene. Insoluble carriers such as polymer spheres, membranes, and fibers can be used. Crosslinked particles composed of a styrene-divinylpentene copolymer are obtained by dispersing styrene and divinylbenzene in water containing a dispersant such as polyvinyl alcohol, polyvinylpyrrolidone, and calcium phosphate. Such a radical polymerization initiator can be obtained by adding the above radical polymerization initiator, heating and stirring to carry out suspension polymerization.

In the present invention, the halogenated alkyl group introduced into the insoluble carrier is a halogenated alkyl group having 1 to 4 carbon atoms, and is preferably a chloromethyl group. When the number of carbon atoms in the halogenated alkyl group is 5 or more, the ion exchange capacity per unit weight of the anion exchange resin becomes small, and the hydrophobicity of the anion exchange resin becomes too strong. There is a risk.

When the insoluble carrier is a copolymer of styrene, the chloromethyl group is reacted by reacting chloromethyl methyl ether in the presence of a catalyst such as anhydrous aluminum chloride, tin tetrachloride, stannic chloride, or anhydrous zinc chloride. Can be introduced. At this time, the reaction can be promoted by using a solvent such as tetrachloroethane or dichloromethane that swells the styrene-divinylbenzene bridge copolymer particles. Chloromethyl methyl ether is usually used in an amount equal to or greater than the amount to be introduced, and when the insoluble carrier is a styrene-divinylbenzene cross-linked copolymer particle, it is 2-3 equivalent times the benzene ring in the particle. It is preferable to use The reaction temperature and reaction time are not particularly limited, and can be appropriately set depending on the catalyst used. For example, when stannic chloride is used, the reaction may be performed at 50 to 70 ° C for 4 to 6 hours. When anhydrous aluminum chloride is used, the activity is high. The reaction may take up to 3 hours. After completion of the reaction, the reaction mixture is preferably filtered to separate chloromethylated particles, and washed with a solvent that does not react with chloromethyl groups, such as chloroform and dichloromethane.

In the present invention, particles such as styrene-divinylbenzene cross-linked copolymer particles into which a halogenated alkyl group has been introduced are dispersed in a solvent such as benzene, chloroform, and dichloromethane to form a primary or secondary amino group and an antioxidant function. By reacting a compound having a group having the following formula, a group having an antioxidant function can be covalently bonded via an iminoalkylene group. Examples of the compound having a primary or secondary amino group and a group having an antioxidant function include, for example, 4-amino-2,2,6,6-tetramethylpiperidine, 4-amino-1,2,2,6, Hindered amine compounds such as 6-pentamethylpiperidine, 2,6-di-tert-butyl-1-aminomethylphenol, 2,6-di-tert-butyl-14-methylaminomethylphenol, 2,6 Hindered phenolic compounds such as di-tert-butyl-4-aminophenol and 2,6-di-tert-butyl-4-aminopropylphenol; The amount of the group having an antioxidant function to be introduced is not particularly limited, but is usually preferably from 0.01 to 10% by weight of the anion exchange resin. Reaction temperature and anti The reaction time is not particularly limited. For example, the reaction can be completed by a reaction at room temperature for several hours.

In the present invention, there is no particular limitation on the amine that is reacted to convert the halogenated alkyl group into a quaternary ammonium group. Examples thereof include trialkylamines such as trimethylamine and dialkylmonoamines such as dimethylmonoethanolamine. Alkanolamine and the like can be mentioned. When the amine is a gas at room temperature, the ammoniating reaction can be terminated by blowing the amine into the reaction system and, for example, reacting at room temperature for 10 to 12 hours.

In the anion exchange resin of the present invention, since a group having an antioxidant function is introduced by a covalent bond, the antioxidant is more oxidized than the conventional method in which the antioxidant is ionically adsorbed or physically retained. The agent does not easily fall off, maintains excellent resistance to oxidative decomposition over a long period of time, and can effectively prevent elution of resin components and deterioration of the resin during use.

Example

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

Example 1

As a group having an antioxidant function, a dispersant composed of sodium polystyrenesulfonate having a 2,2,6,6-tetramethyl-14-piperidinyl group covalently bonded thereto was synthesized.

Sodium styrenesulfonate [Tokyo Kasei Kogyo Co., Ltd.] 13.80 g (67.0 mimol), 2,2,6,6-tetramethyl-4-piperidinyl methacrylate [Asahi Denka Kogyo Co., Ltd. ), ADK STAB LA—87] 0.68 g (3.0 millimoles) and 80 ml of water were placed in a 500 ml separable flask, and the flask was immersed in an ice water bath to keep the temperature low. Hydrochloric acid was added dropwise until 2,2,6,6-tetramethyl-4-piperidinyl methacrylate was dissolved, and 20 ml of water was further added. The pH of the resulting solution was 4.1.

Attach a lid equipped with a nitrogen gas inlet tube to the separable flask, Blowed at OmlZ minutes for 30 minutes. One milliliter of an aqueous solution obtained by dissolving 140 mg of potassium persulfate [Kishida Chemical Co., Ltd.] in 5.2 ml of water was added thereto, and the amount of nitrogen gas blown was 60 mlZ, and the mixture was heated at 45 ° C for 15.5 hours to carry out polymerization. An aqueous sodium hydroxide solution was added to the reaction mixture to adjust the pH to 8.1, and the mixture was poured into acetone, and the precipitated product was separated by filtration and vacuum-dried. 13.10 g of a white solid was obtained.

The infrared absorption spectrum of the obtained product shows an absorption band derived from the benzene ring at 3070 cm-3030 cm1 600 cm-1500 cm-835 cm- ^1.

. 5 cm ". ¹ 2850cm- absorption band derived from the methylene group in ^{^{1, 1200cm- 1130 cm" 1 1040cm}} '101 Ocnr absorption band derived from a sulfonic group in ^1, 1720 cm - ¹ to 2, 2, 6, 6- An absorption band based on the C = 〇 stretching vibration of the ester bond of tetramethyl-1-piperidinyl methacrylate was observed. From these results, it was confirmed that the product was a copolymer of sodium styrenesulfonate and 2,2,6,6-tetramethyl-14-piperidinyl methacrylate.

A 0.5% by weight aqueous solution of this copolymer was prepared, and the viscosity of the solution was measured at 20 ° C. using a B-type viscometer. Next, 200 ml of this solution was placed in a beaker, a 6% by weight aqueous solution of hydrogen peroxide was added at 50 // 1, and the mixture was placed in a 50 ° C water bath and heated for 4 days. Thereafter, when the temperature was returned to 20 ° C. and the solution viscosity was measured, it was 22 cP, and there was no change in the solution viscosity.

Comparative Example 1

A dispersant consisting of sodium polystyrene sulfonate was synthesized.

As in Example 1, except that 2, 2, 6, 6-tetramethyl_4-piperidinyl methacrylate was not used and the pH of the solution was not adjusted.

66 g of sodium polystyrene sulfonate was obtained as a white solid.

A 0.5% by weight aqueous solution of the obtained sodium polystyrene sulfonate was prepared, and in the same manner as in Example 1, the solution viscosity immediately after preparation and hydrogen peroxide were added, and the mixture was heated for 4 hours in a 50 ° C water bath. The solution viscosity afterwards was measured. The solution viscosity immediately after preparation was 56 cP, and the solution viscosity after adding a hydrogen peroxide solution and heating was 15 cP. As shown in Example 1 and Comparative Example 1, a group having an antioxidant function is covalently bonded. The solution viscosity of sodium polystyrene sulfonate does not change, whereas the solution viscosity of sodium polystyrene sulfonate, to which a group having an antioxidant function is not bonded, is greatly reduced. From these results, it is clear that oxidative decomposition of sodium polystyrene sulfonate can be prevented by covalently bonding a group having an antioxidant function.

Example 2

A powdered cation exchange resin having a 2,2,6,6-tetramethyl-14-piperidinyl group covalently bound as a group having an antioxidant function was synthesized.

Sodium styrene sulfonate 15.00 g (72.8 mimol), styrene

[Tokyo Kasei Kogyo Co., Ltd.] 1.54 g (14.8 mimol) divinylbenzene [Tokyo Kasei Kogyo Co., Ltd., 55% by weight of active ingredient] 1.75 g (7.4 mimol), 2, 2, 6, 6-tetramethyl 1.04 g (4.6 mmol) of 4-piperidinyl methacrylate and 195 ml of dimethylformamide were placed in a 50-ml separable flask. A Teflon blade for stirring and a lid equipped with a nitrogen gas inlet tube were attached, and nitrogen gas was blown in at 30 OmlZ for 1 hour while stirring at 40 rpm.

Next, 6 ml of a solution of 66 mg of 22'-azobisisobutyronitrile [Kishida Chemical Co., Ltd.] dissolved in 12 ml of dimethylformamide was added. Heated for 17 hours. The amount of nitrogen gas blown was 5 OmlZ minutes two hours after the start of heating. The formed white precipitate is filtered off, washed with dimethylformamide and acetone in that order, and dried in vacuo to obtain 13.42 g of a powdery product o

The obtained product does not dissolve in water, and the infrared absorption spectrum of the product is determined by comparing the sodium styrenesulfonate obtained in Example 1 with 2,2,6,6-tetramethyl-1-piperidine. The product obtained is sodium styrenesulfonate, styrene, divinylbenzene and 2,266-tetramethyl-14-piperidinium, since the absorption spectrum is the same as that of the methyl methacrylate copolymer. It was confirmed that it was a copolymer of nilmethacrylate.

Take 0.39 g of the obtained powdery copolymer in a 250 ml washing bottle, and add 200 ml of water. Was added. The powdery copolymer swelled to an apparent volume of about 25 ml. 31% by weight of a hydrogen peroxide solution 50a1 was added, and the mixture was heated overnight in a 70 ° C water bath. Thereafter, the amount of organic carbon (TOC) in the supernatant was measured and was found to be 18 ppm.

Comparative Example 2

A group having an antioxidant function was bonded to form an L-type powdered cation exchange resin.

As in Example 2, using 16.06 g (78.0 mimol) of sodium styrenesulfonate, 1.54 g (14.8 mimol) of styrene and 1.75 g (7.4 mimol) of divinylbenzene [55% by weight of active ingredient] The synthesis was performed to obtain 13.61 g of a copolymer of sodium styrenesulfonate, styrene and divinylbenzene.

0.43 g of the obtained powdery copolymer was placed in a 250 ml air-washing bottle, and 200 ml of water was added. The copolymer swelled to an apparent volume of about 25 ml. Then, 50/1 of 31% by weight aqueous hydrogen peroxide was added, and the mixture was heated overnight in a 70 ° C water bath. Thereafter, the amount of organic carbon in the supernatant was measured and found to be 34 ppm.

As can be seen in Example 2 and Comparative Example 2, the amount of organic carbon in the supernatant of the cation exchange resin to which a group having an antioxidant function is covalently bonded is determined by the amount of the group having an antioxidant function. Since the amount of the organic carbon in the supernatant of the cation exchange resin that has not been subjected to the reaction is smaller than that of the supernatant, it is understood that the decomposition and elution of the resin are suppressed by covalently bonding a group having an antioxidant function.

Example 3

We have synthesized a particulate cation exchange resin in which a 2,2,6,6-tetramethyl-14-piperidinyl group is covalently bonded as an antioxidant group.

Styrene 35.10 g (337.5 mmol), divinylbenzene [55% by weight of active ingredient] 7.62 g (32.2 mmol), 2,2,6,6-tetramethyl-14-piperidinyl methacrylate 4.59 g (20.4 mmol) 0.25 g of 2,2,1-azobisisobutyronitrile and 2,2,1-azobisisobutyronitrile were placed in a 500 ml separable flask, and nitrogen gas was blown in at 20 OmlZ for 30 minutes to deoxygenate. To this monomer mixture, add 0.06 g of polyvinyl alcohol [Kishida Chemical Co., Ltd., degree of polymerization 2,000, degree of saponification 78-82 mol%] and polyvinyl alcohol [Kishida Chemical Co., Ltd., degree of polymerization 2,000, degree of gentification 98.5-99.4] Mol%] was added to 500 ml of water and dissolved by heating, and then 200 ml of an aqueous polyvinyl alcohol solution prepared by filtration using No. 5A filter paper was added.

A lid equipped with a Teflon blade for stirring and a nitrogen gas inlet tube was attached, and stirring was performed at 150 rpm while blowing nitrogen gas at a rate of 15 OmlZ. The separable flask was placed in a constant temperature water bath maintained at 70 ° C., and the nitrogen gas was blown at a rate of 1 O OmlZ, and heated for 17 hours. The resulting white particles were collected by filtration through No. 5A filter paper, washed with water, methanol, chloroform, and methanol in that order, and dried in vacuo at room temperature to obtain 45.95 g of a particulate product. .

The obtained product does not dissolve in pore-form, and the infrared absorption spectrum of the product has C = 0 of the ester bond of 2,2,6,6-tetramethyl-4-piperidinyl methacrylate. Since the absorption band at 1720 cm- ¹ based on stretching vibration was observed, the obtained product was a copolymer of styrene, divinylbenzene and 2,2,6,6-tetramethyl-4-piperidinyl methacrylate. It was confirmed that there was.

35.00 g of the obtained particulate copolymer and 125 ml of tetrachloroethane were placed in a 500 ml separable flask, and heated at 60 ° C for 30 minutes. After cooling to room temperature, a Teflon blade for stirring and a lid equipped with a nitrogen gas inlet tube were attached. Nitrogen gas was blown near the liquid surface at 5 OmlZ, and 50 ml of chlorosulfonic acid [Wako Pure Chemical Industries, Ltd.] was added little by little while stirring at 8 Orpm, and the mixture was reacted at room temperature for 4 hours. After adding 15 ml of acetic acid, the product was recovered by filtration. After washing with tetrachloroethane, the product was poured into water, filtered, and washed with acetone and water in this order. The product after washing, 40.00 g of sodium acetate and 200 ml of water are placed in a 500 ml separable flask, immersed in a constant temperature water bath maintained at 40 ° C, and blown with nitrogen gas at 75 ml / min. Stirred for hours. The product was collected by filtration and washed with water.

The infrared absorption spectrum of the product, 120 Ocnr ^{1 1} derived from a sulfonic acid group An absorption band of 13 Ocm ^ 1040cm-1010cm- ¹ was observed. In addition, the absorption band of 172 Ocra- ¹ based on the C = エステル stretching vibration of the ester bond of 2,2,6,6-tetramethyl-4-piperidinyl methacrylate was also recognized, and a group having an antioxidant function was bonded. It was confirmed that.

Example 4

As a group having an antioxidant function, 2- [1- (2'-hydroxy-3 ', 5'-di-tert-pentylphenyl) ethyl] -1,4,6-di-t-pentylphenyl groups are covalently bonded to particles. A cation exchange resin was synthesized.

Styrene 26.52 g (255.0 mimol), divinylbenzene [active ingredient 55% by weight] 7.09 g (30.0 mimol), 2- [1- (2'-hydroxy-1 3 ', 5'-G-t-pentylphenyl) 1,6-di-t-pentylphenylacrylate [Sumitomo Chemical Co., Ltd., Sumilizer-GS] 8.22 g (15.0 mimol) and 2,2'-azobisisobutyronitrile 0.25 g was taken in a 500 ml separable flask and deoxygenated by blowing nitrogen gas at 200 ml / min for 30 minutes. To this monomer mixture, 0.06 g of polyvinyl alcohol [Kishida Chemical Co., Ltd., degree of polymerization: 2,000, degree of polymerization: 78 to 82 mol%] and polyvinyl alcohol [Kishida Chemical Co., Ltd., degree of polymerization: 2,000, A degree of genification of 98.5 to 99.4 mol, 1.44 g, was added to 500 ml of water, dissolved by heating, and then 200 ml of an aqueous polyvinyl alcohol solution prepared by filtration using No. 5A filter paper was added.

A lid equipped with a Teflon blade for stirring and a nitrogen gas inlet tube was attached, and the mixture was stirred at 15 Orpm while blowing nitrogen gas at 15 OmlZ. The separable flask was placed in a thermostatic water bath maintained at 70 ° C, and the nitrogen gas was blown at 10 OnilZ minutes, and heated for 17 hours. The resulting white particles were collected by filtration through a No. 5A filter paper, washed with water, methanol, chloroform, and methanol in that order, and vacuum dried at room temperature to obtain 23.76 g of a particulate product. Obtained.

The obtained product does not dissolve in black-mouthed form, and the infrared absorption spectrum of the product contains 2- [1-1 (2'-hydroquinone-3 ', 5'-t-pentylphenyl) ethyl] C = 0 stretching of ester bond of 1,4,6-di-t-pentylphenyl acrylate The absorption band of 172 Ocnr ¹ based on the vibration and the absorption band of 361 Ocm- ¹ based on the 0-H stretching vibration were observed, indicating that the obtained products were styrene, divinylbenzene and 2- [1-1 (2 , 1-hydroxy_3 ', 5'-di-t-pentylphenyl) ethyl] —4,6-di-t-pentylphenylacrylate.

20.00 g of the obtained particulate copolymer and 70 ml of tetrachloroethane were placed in a 300 ml separable flask and heated at 60 ° C for 30 minutes. After cooling to room temperature, a Teflon blade for stirring and a lid equipped with a nitrogen gas inlet tube were attached. Nitrogen gas was blown into the vicinity of the liquid surface at a volume of 50 mlZ, and 30 ml of chlorosulfonic acid [Wako Pure Chemical Industries, Ltd.] was added little by little while stirring at 8 Orpm, and the mixture was reacted at room temperature for 4 hours. After adding 10 ml of acetic acid, the product was recovered by filtration. After washing with tetrachlorene, the product was thrown into water, filtered, and washed with acetone and water in that order. Transfer the washed product, sodium acetate (25.00 g) and water (120 ml) to a 300 ml separable flask, immerse it in a constant temperature water bath maintained at 40 ° C, and blow nitrogen gas at 75 ml for 6 hours at 4 Orpm. Stirred. The product was collected by filtration and washed with water.

The infrared absorption spectrum of the product, the absorption band of ^{120 Ocnr 1 1 13 Ocnr 1040cm- 101} Ocnr 1 derived from a sulfonic acid group was observed. Also, the C = 0 stretching vibration of the ester bond of 2- [1- (2'-hydroxy_3 ', 5'_di-t-pentylphenyl) ethyl] -4,6-di-t-pentylphenylacrylate 172 Ocnr ¹ absorption band based on 0-H stretching vibration and 361 Ocnr ¹ absorption band based on 0-H stretching vibration, confirming that a group having an antioxidant function is bonded. Example 5

A cation exchange resin having a 2,2,6,6-tetramethyl-4-piberidinyl group covalently bound as a group having an antioxidant function was synthesized.

185 ml of styrene-divinylbenzene crosslinked copolymer particles [manufactured by Supe 1 c 0. Inc., specific surface area 330 m ² / g, average pore size 9 OA] are mixed with water, methanol, chloroform, and tetrachlorene. And washed in this order. The crosslinked particles and Tet 85 ml of lachlorethane was placed in a 50 Oml separable flask, fitted with a lid equipped with a Teflon blade for stirring, a nitrogen gas inlet tube, and a cooling tube, heated at 60 ° C for 30 minutes, and then returned to room temperature. Nitrogen gas was blown near the liquid surface at 60 ml / min, and while stirring at 60 rpm, 75 ml of chlorosulfonic acid [manufactured by Wako Pure Chemical Industries, Ltd.] was added little by little. . Next, 10 ml of acetic acid was added and the mixture was stirred, and the resulting chlorsulfonated particles were collected by filtration. The chlorsulfonated particles were washed with tetrachloroethane, then put in water, and further washed with acetone and chloroform.

The chlorsulfonated particles, 150 ml of black-mouthed form and 10 ml of triethylamine were placed in a 500 ml separable flask, and fitted with a Teflon blade for stirring, a nitrogen gas inlet tube, and a lid equipped with a cooling tube. Nitrogen gas was blown near the liquid surface at a rate of 60 ml / min, and while stirring at 6 O rpm, 4.58 g of 4-amino-2,2,6,6-tetramethylpiberidine was dissolved in 30 ml of Cloth form. The solution was added dropwise and reacted overnight. The generated particles were collected by filtration, and washed with port-form, acetone, and water in this order.

The obtained particles, 40 g of sodium acetate and 200 ml of water were placed in a 500 ml separable flask, and a lid equipped with a Teflon blade for stirring, a nitrogen gas inlet tube, and a cooling tube was attached. The separable flask was immersed in a thermostatic water bath maintained at 45 ° C, and stirred at 4 Orpm for 6 hours while blowing nitrogen gas at 75 mlZ. The product was collected by filtration and washed with water.

The infrared absorption spectrum of the product, 1 derived from the sulfone group, 20 Ocnr ^ 1, 130cm- 1 , 04 Ocnr 1 and 1, the absorption band of 010cm- ¹ was observed. Also, the ion exchange capacity was measured and was 1.2 meq / ml. Elemental analysis revealed 0.6% by weight of nitrogen, confirming that 4-amino-2,2,6,6-tetramethylbiperidine had been introduced. The amount of the group having an antioxidant function based on the weight of the resin was 3% by weight.

50 ml of the obtained 2,2,6,6-tetramethyl-4-pyridinyl group-covalently bound cation exchange resin (H-type) is placed in a cleansing bottle, and the total volume of ultrapure water is reduced to 200 ml. Added until it was. Oxygen gas was blown in at an amount of 1 OmlZ, and the supernatant was collected before the start of the test, after 8, 14 and 21, and subjected to size exclusion chromatography analysis. The analysis was performed at a detection wavelength of 200 nm using Shodex SB-802.5 HQ as the column and a mobile phase of acetonitrile Z2OmM lithium chloride (2Z8). Under these conditions, organic sulfonic acids such as polymers of sulfobenzoic acid, phenolsulfonic acid, and styrenesulfonic acid can be detected with high sensitivity. The amount of organic sulfonic acid dissolved in the supernatant was calculated from the calibration curve prepared in advance for the concentration of sulfobenzoic acid and the peak area in terms of the amount of sulfobenzoic acid per liter of resin.

The elution amount of sulfobenzoic acid was 0 mg before the start of the test, 10 mg after 8 days, 35 nig after 14 and 4 lmg after 21.

Comparative Example 3

The dissolution test was performed in the same manner as in Example 5 using a commercially available cation exchange resin [650-C, manufactured by Dow Chemical Co., Ltd.].

The dissolution amount of sulfobenzoic acid was 0 _mg before the start of the test, 26 mg after 8 days, 79 mg after 14 days, and 149 mg after 21 days.

FIG. 1 shows the results of the dissolution test of Example 5 and Comparative Example 3. From this figure, it can be seen that the eluate from a commercially available cation exchange resin increases with time due to oxidative decomposition, whereas the group having an antioxidant function is covalently bonded via a sulfonamide bond, and It can be seen that elution of sulfobenzoic acid and the like is suppressed in the force-exchange resin of the invention.

Example 6

We have synthesized anion-exchange resin with 2,2,6,6-tetramethyl-4-piperidinyl group covalently bound as a group with antioxidant function.

300 g of chloromethylated styrene divinylbenzene cross-linked copolymer particles [A 1 drich Chemical Co., In, cross-linking degree 2%, 1 meq C 1 / g] Place in a separable flask, attach a lid equipped with a Teflon blade for stirring, a nitrogen gas inlet tube, and a cooling tube, and at 60 ° C for 30 minutes After heating, it was cooled to room temperature. Nitrogen gas is blown near the liquid level at 6 Oml / min.

While stirring at 6 Orpm, 4-amino-1,2,2,6,6-tetramethylpiperidine 4.

A solution prepared by dissolving 7 g in 3 Oml of form-form was added dropwise and allowed to react overnight. The generated particles were collected by filtration, and washed with black form and benzene. Elementary analysis was conducted by sampling a small amount of these particles, and as a result, 88.8% by weight of carbon and 0.6% by weight of nitrogen were detected, confirming that 4-amino-2,2,6,6-tetramethylbiperidine was introduced. Was done. The amount of the group having an antioxidant function based on the weight of the resin was 3% by weight.

The particles into which 4-amino-2,2,6,6-tetramethylpiperidine has been introduced are placed in a 300 ml separable flask together with 100 ml of benzene, and a lid equipped with a Teflon blade for stirring, a nitrogen gas inlet tube, and a cooling tube is provided. After mounting and heating at 60 ° C for 30 minutes, the temperature was returned to room temperature. Next, trimethylamine gas was blown at a rate of 5 ml / min for 30 minutes, followed by reaction at room temperature overnight. The resulting anion exchange resin particles were collected by filtration, washed with acetone, and air-dried. When the ion exchange capacity of the anion exchange resin was measured, it was 1.0 meqZ g.

50 ml of the obtained anion exchange resin (OH type) to which 2,2,6,6-tetramethyl-4-piperidinyl group was covalently bonded was taken in an air-washing bottle, and ultrapure water was added until the total volume became 200 ml. Oxygen gas was blown in at an amount of 1 OmlZ, and after 14 minutes, the supernatant was collected and the organic carbon (TOC) was measured according to JIS K0101. The amount of eluted organic carbon was 2 Omg per ml of anion exchange resin.

Comparative Example 4

The same dissolution test as in Example 6 was performed using a commercially available anion exchange resin [Mitsubishi Chemical Corporation, SA10A, OH type] instead of the anion exchange resin to which a group having an antioxidant function was bonded. The amount of eluted organic carbon was 5 Omg per ml of anion exchange resin.

From the results of the dissolution tests of Example 6 and Comparative Example 4, the amount of organic carbon eluted from the anion exchange resin of the present invention in which the group having an antioxidant function was covalently bound was determined from the commercially available anion exchange resin. About 40% of the amount of organic carbon eluted, It can be seen that the resin has excellent resistance to oxidative decomposition and the elution of the resin component is suppressed. Industrial applicability

Since the polymer water treatment material of the present invention has a group having an antioxidant function covalently bonded thereto, there is little risk of deterioration in performance due to oxidative deterioration and contamination of water quality due to oxidative decomposition products during use, and a flocculant It can be suitably used for water treatment as a dehydrating agent, a dispersing agent, a membrane and the like. The cation exchange resin and the anion exchange resin of the present invention have excellent oxidation resistance and little elution of resin components because the group having an antioxidation function is covalently bonded.

Claims

The scope of the claims

1. A polymer water treatment material, characterized in that a group having an antioxidant function is covalently bonded.

2. When the group having antioxidant function is a hindered amine, monocyclic or polycyclic hindered phenol, thioester, thioether, amine, phosphorus, benzophenone, salicylate or triazole type The polymer water treatment material according to claim 1, which is a base.

3. A cation exchange resin wherein a group having an antioxidant function is covalently bonded via a sulfonamide bond represented by the general formula [1].

-SOzNR ^1- … [1]

(Wherein, R ¹ is hydrogen or a methyl group.)

4. The cation exchange resin according to claim 3, wherein the group having an antioxidant function is a hindered amine group or a hindered phenol group.

5. An anion exchange resin, wherein a group having an antioxidant function is covalently bonded via an iminoalkylene bond represented by the general formula [2].

One (CH ₂ ) nNR ^2- … [2]

(Wherein, R ² is hydrogen or a methyl group, and n is an integer of 1 to 4.)

6. The anion exchange resin according to claim 5, wherein the group having an antioxidant function is a hindered amine group or a hindered phenol group.