JP6974410B2 - Aqueous polystyrene sulfonic acid curable composition and a cured product formed from the composition. - Google Patents

Description

The present invention relates to an aqueous polystyrene sulfonic acid curable composition useful as an antistatic coating film and a fiber treatment agent, and a cured product formed from the composition.

Polystyrene sulfonic acid (or a salt thereof) is an aromatic water-soluble polymer and has excellent heat resistance, chemical stability, and adsorptivity. Therefore, it disperses carbon materials, various cleaning agents, antistatic agents, and fibers. It is used in a wide range of industrial fields such as treatment agents and synthetic glues.

There are some improvements to polystyrene sulfonic acid (or salts thereof), but there is a strong demand for crosslinkable polystyrene sulfonic acid (and salts thereof), for example, in fiber treatment agents, dispersion of carbon materials, and antistatic agents. .. For example, it is known that by immersing viscose rayon having a cationic group in a polymer in an aqueous solution of sodium polystyrene sulfonate, an anti-allergen fiber in which sodium polystyrene sulfonate is retained on the surface of viscose rayon can be produced. (See, for example, Patent Document 1).

However, since sodium polystyrene sulfonate is retained on the surface of viscose rayon only by electrostatic interaction, there is a problem that water-soluble sodium polystyrene sulfonate is shed by washing or the like.

Further, for example, it is known that graphitic particles whose surface is coated with sodium polystyrene sulfonate can be used as a carbon material for a negative electrode of a non-aqueous secondary battery (see, for example, Patent Document 2).

However, since the film of sodium polystyrene sulfonate is uncrosslinked and swelling due to the electrolytic solution solvent is unavoidable, there is a problem that a side reaction between the surface of the graphite particles and the electrolytic solution cannot be sufficiently suppressed.

Further, for example, when preparing an antistatic thin film using sodium polystyrene sulfonate having a specific reactive group introduced therein, a water-soluble epoxy resin is added as a cross-linking agent, and the mixture is heated and dried at 130 ° C. to withstand a solvent. It is known that an antistatic thin film of polystyrene sulfonic acid (or a salt thereof) having excellent properties and water resistance can be formed (see, for example, Patent Document 3).

However, in order to introduce a reactive group into sodium polystyrene sulfonate, it is possible to copolymerize special monomers such as 4-vinylbenzoic acid, 4-aminostyrene and 4-hydroxystyrene, which have extremely low versatility, and to use a large amount of epoxy as a cross-linking agent. There are problems such as the need to add a resin and the need for long-term heating at a high temperature. In order to solve the problems in the above applications, polystyrene sulfonic acid (or a salt thereof) that can be easily and efficiently crosslinked has been strongly demanded.

Japanese Patent No. 5385692 Japanese Unexamined Patent Publication No. 2014-186955 Japanese Unexamined Patent Publication No. 2016-204646

Little is known about water-soluble polystyrene sulfonic acid (or a salt thereof) that can be easily and efficiently crosslinked, and water-based polystyrene sulfonic acid (or a salt thereof) that is simple, has high crosslinking efficiency, and has excellent coatability (fluidity). The salt) curable composition has been strongly sought.

As a result of diligent research to solve the above problems, the present inventors have made polystyrene sulfonic acid (or a salt thereof) modified with a general-purpose monomer such as (meth) acrylic acid, and a polymer containing a plurality of oxazoline groups. , And a polystyrene sulfonic acid curable composition containing a hydrophilic solvent having a specific structure, which has excellent coatability (fluidity) and can be easily and efficiently crosslinked, was found to complete the present invention. It came.

That is, the present invention
The present invention relates to an aqueous polystyrene sulfonic acid curable composition containing the following components (A) to (D).
(A) Including the structural unit (a) represented by the following general formula (1) and the structural unit (b) represented by the general formula (2), with respect to the total of the structural unit (a) and the structural unit (b). Polystyrene sulfonic acid structural unit (a) in which the molar ratio of the structural unit (b) is 2 mol% to 60 mol%;
General formula (1)

(In the formula (1), M ₁ represents a proton, an ammonium ion, a quaternary ammonium cation, a quaternary phosphonium cation, an alkali metal cation or an alkaline earth metal cation). And structural unit (b);
General formula (2)

(Equation (2), Q ₁ represents a radical polymerizable monomer residue having a carboxyl group.) A carboxyl group-containing monomer structural unit represented by,
(B) A polymer containing a plurality of oxazoline groups,
(C) A hydrophilic solvent selected from the group consisting of glycol ethers and alcohols having 1 to 4 carbon atoms, or a combination of two or more kinds, and (D) water (provided that the above component (A) and (B) are used. The compounding ratio of the components is 10: 2 to 2:10 in terms of the equivalent ratio of the carboxyl group and the oxazoline group, and the compounding ratio of the components (A) and (B) to the total amount of the components (A) to (D) is It is 0.5 wt% to 30 wt%, and the blending ratio of the component (C) to the total amount of the component (C) and the component (D) is 10 wt% to 70 wt%). )

The present invention also relates to an aqueous polystyrene sulfonic acid curable composition containing the following components (A'), (B), (C) and (D).
(A') The structural unit (a) represented by the following general formula (3), the structural unit (b) represented by the general formula (4), and the structural unit (c) represented by the general formula (5). Including, the molar ratio of the structural unit (b) to the total of the structural unit (a), the structural unit (b) and the structural unit (c) is 2 mol% to 60 mol%, and the structural unit (a) and the structural unit ( The polystyrene sulfonic acid structural unit (a) in which the molar ratio of the structural unit (c) to the sum of b) and the structural unit (c) is 1 mol% to 30 mol%;
General formula (3)

(In the formula (3), M ₁ represents a proton, an ammonium ion, a quaternary ammonium cation, a quaternary phosphonium cation, an alkali metal cation or an alkaline earth metal cation).
Structural unit (b);
General formula (4)

(. Equation (4), Q ₁ is representative of the radical polymerizable monomer residue having a carboxyl group) carboxyl group-containing monomer structural units represented by, and the structural unit (c);
General formula (5)

(Equation (5) in, Q ₂ represents. A radical polymerizable monomer residues containing no carboxyl group) structure units of a monomer containing no carboxyl group represented by,
(B) A polymer containing a plurality of oxazoline groups,
(C) A hydrophilic solvent selected from the group consisting of glycol ethers and alcohols having 1 to 4 carbon atoms, or a combination of two or more kinds, and (D) water (provided that the above (A') component and (B). The blending ratio of the component) is 10: 2 to 2:10 in terms of the equivalent ratio of the carboxyl group to the oxazoline group, with respect to the total amount of the component (A'), the component (B), the component (C) and the component (D). The blending ratio of the component (A') and the component (B) is 0.5 wt% to 30 wt%, and the blending ratio of the component (C) to the total amount of the components (C) and (D) is 10 wt% to 70 wt%. ). )

The present invention, Q ₁ is methacrylic acid (salt) residues, acrylic acid (salt) residue, maleic acid (salt) residue, the group consisting of citraconic acid (salt) residues and itaconic acid (salt) residues The present invention relates to the above-mentioned aqueous polystyrene sulfonic acid curable composition which is a radically polymerizable monomer residue which is a combination of at least one kind or a combination of two or more kinds selected.

Further, the present invention, Q ₂ is styrene residue, methyl methacrylate residues, 2-hydroxyethyl residues methacrylate, methacrylamide residue, at least one selected from the group consisting of N- phenylmaleimide residue or 2 The present invention relates to the above-mentioned aqueous polystyrene sulfonic acid curable composition which is a radically polymerizable monomer residue which is a combination of species or more.

The present invention also relates to the above-mentioned aqueous polystyrene sulfonic acid curable composition having a weight average molecular weight of 5000 daltons (Da) to 4000 thousand daltons (Da) determined by gel permeation chromatography of polystyrene sulfonic acid.

Further, in the present invention, the glycol ether is methoxyethanol, ethoxyethanol, ethylene glycol monopropyl ether, 1-methoxy-2-propanol, 1,2-dimethoxypropane, 2-methoxy-1-methylethyl acetate, 2-methoxy acetate. Methyl, propylene glycol monomethyl ether, 3-methoxy-3-methyl-1-butanol, 1 (or 2)-[2-methoxy (methyl) ethoxy] propanol, bis (3-hydroxypropyl) ether, bis (2-hydroxy) The present invention relates to the above-mentioned aqueous polystyrene sulfonic acid curable composition, which is at least one selected from the group consisting of propyl) ether and dipropylene glycol monomethyl ether.

The present invention also relates to the above-mentioned aqueous polystyrene sulfonic acid curable composition, wherein the alcohol is at least one selected from the group consisting of methanol, ethanol, 1-propanol, 2-propanol, ethylene glycol, propylene glycol and butanol. Related.

The present invention also relates to a water-insoluble polystyrene sulfonic acid cured product formed from the above-mentioned aqueous polystyrene sulfonic acid curable composition and represented by the following general formula (6).
General formula (6)

(In the formula (6), M ₁ is the same as the above formula (1), Q ₁ is the same as the above formula (4), and Q ₃ is a polymer having a plurality of oxazoline groups which is a component of the above (B). Represents the main chain of. N, m and k represent integers greater than or equal to 1.)

The aqueous polystyrene sulfonic acid curable composition of the present invention comprises polystyrene sulfonic acid (or a salt thereof) modified with a general-purpose monomer such as (meth) acrylic acid, a polymer containing a plurality of oxazoline groups, and hydrophilicity having a specific structure. It is an aqueous curable composition containing a sex solvent and has excellent coatability (fluidity) and curability, so that it is extremely useful in a wide range of industrial fields such as fiber treatment, antistatic agents, and coating of carbon materials.

Hereinafter, embodiments for carrying out the present invention will be described in detail. The present invention is not limited to the following embodiments. The present invention can be appropriately modified and carried out within the scope of the gist thereof.

The polystyrene sulfonic acid (or a salt thereof) used in the present invention is a polystyrene sulfonic acid having a plurality of carboxyl groups as cross-linking sites (hereinafter referred to as carboxyl-modified PSS). A polymer containing a plurality or a plurality of oxazolines (hereinafter referred to as polyoxazoline) is mixed with an aqueous solution containing a carboxyl-modified PSS, the mixed solution is spread in a container such as a chalet, and when heated and dried, the carboxyl-modified is insoluble in water. A cured product of PSS is formed. It is known that a polymer modified with a carboxyl group can be crosslinked with polyoxazoline (see, for example, Japanese Patent No. 3191978 and Japanese Patent No. 3259147).

However, when the present inventors mixed polyoxazoline in an aqueous solution of a polymer containing a styrene sulfonic acid structural unit as a main component, such as carboxyl-modified PSS, the viscosity was violently increased and the fluidity was impaired, so that the coating on the substrate was applied. Turned out to be difficult.

The present inventors have found that by adding a hydrophilic solvent having a specific structure to the mixed solution, thickening is suppressed, fluidity is restored, and good coatability is exhibited, leading to the present invention. rice field.

First, the carboxyl-modified PSS of the present invention will be described.

The carboxyl-modified PSS is a polystyrene sulfonic acid (or a salt thereof) containing 2 mol% to 60 mol% of a carboxylic acid monomer structural unit with respect to the total of the styrene sulfonic acid structural unit and the carboxylic acid monomer structural unit contained in the polymer. Is. From the viewpoint of maintaining the original properties of polystyrene sulfonic acid and crosslinkability, the structural unit of the carboxylic acid monomer in the carboxylic acid-modified PSS is more preferably 5 mol% to 50 mol%.

The method for producing a carboxylic acid-modified PSS can be roughly divided into two.

<First manufacturing method>
The first production method is a method of radically copolymerizing styrene sulfonic acid and a carboxylic acid monomer.

Examples of the styrene sulfonic acid used include sodium styrene sulfonate, potassium styrene sulfonate, ammonium styrene sulfonate, lithium styrene sulfonate, styrene sulfonic acid ester and the like, and examples of the carboxylic acid monomer include methacrylic acid and acrylic acid. Examples thereof include vinyl benzoic acid, (anhydrous) maleic acid, (anhydrous) citraconic acid, itaconic acid, and fumaric acid. Among these, sodium styrene sulfonate or lithium styrene sulfonate is preferable, and sodium styrene sulfonate, which is versatile, is more preferable from the viewpoint of availability.

As the carboxylic acid monomer used, methacrylic acid, acrylic acid or maleic acid is more preferable from the viewpoint of copolymerizability and availability. These carboxylic acid monomers may be neutralized with bases such as ammonia, amines and metal oxides, but are neutralized with unneutralized or low boiling point bases such as ammonia in consideration of reactivity with polyoxazoline. Alternatively, it is preferably partially neutralized. Neutralization or partial neutralization may be carried out during or after the polymerization of the styrene sulfonic acid and the carboxylic acid monomer.

In the second production method, after copolymerizing styrene with the above-mentioned carboxylic acid monomer, a sulfonate agent such as sulfur trioxide or fuming sulfuric acid is used in a solvent inert to the sulfonate reaction such as a halogenated solvent. This is a method of sulfonation of styrene units.

Hereinafter, a method for producing a carboxylic acid-modified PSS will be described, but first, the first method will be described in detail.

Regarding the method for producing a carboxylic acid-modified PSS, the first production method is a method for radically copolymerizing a styrene sulfonic acid and a carboxylic acid monomer. The method for radically copolymerizing the styrene sulfonic acid and the carboxylic acid monomer is not particularly limited.

For example, a batch addition polymerization method in which a monomer used for a reaction, a polymerization initiator, a polymerization solvent, and if necessary, a molecular weight adjuster or a chain transfer agent are collectively charged into a polymerization container and polymerized, a monomer or a monomer and a molecular weight adjuster are used. Examples thereof include a sequential addition polymerization method in which the mixed solution of the above and the polymerization initiator are sequentially added to the polymerization vessel to polymerize. Among these, the sequential addition polymerization method, in which the heat of polymerization can be easily removed, is preferably used. However, when the living radical polymerization method is used, the total batch addition polymerization may be preferable to the sequential addition polymerization method in terms of the polymerization conversion rate and the molecular weight controllability.

The polystyrene sulfonic acid used in the present invention is basically a copolymer having the above-mentioned styrene sulfonic acid structural unit as a main component and a carboxylic acid monomer structural unit as a cross-linking site, but does not impair the characteristics of the polystyrene sulfonic acid. as long as it and does not impair the crosslinking reaction of the carboxyl group and an oxazoline group, a monomer other than the above, i.e. may be copolymerized a monomer corresponding to the monomer to form the Q ₂ to which represented in the general formula (5).

In the present invention, examples of the comonomer used for copolymerization include N-cyclohexylmaleimide, N-methylmaleimide, N-ethylmaleimide, N-phenylmaleimide, N- (chlorophenyl) maleimide, N- (methylphenyl) maleimide, and N. -(Isopropylphenyl) maleimide, N- (sulfophenyl) maleimide, N-methylphenylmaleimide, N-bromophenylmaleimide, N-naphthylmaleimide, N-hydroxyphenylmaleimide, N-methoxyphenylmaleimide, N-carboxyphenylmaleimide , N- (nitrophenyl) maleimide, N-benzylmaleimide, N- (4-acetoxy-1-naphthyl) maleimide, N- (4-oxy-1-naphthyl) maleimide, N- (3-fluoranchil) maleimide, N -(5-Fluoresenyl) maleimide, N- (1-pyrenyl) maleimide, N- (2,3-xylyl) maleimide, N- (2,4-xsilyl) maleimide, N- (2,6-xsilyl) maleimide, N- (aminophenyl) maleimide, N- (tribromophenyl) maleimide, N- [4- (2-benzoimidazolyl) phenyl] maleimide, N- (3,5-dinitrophenyl) maleimide, N- (9-acrydinyl) Maleimides such as maleimide, dibutyl fumarate, dipropyl fumarate, diethyl fumarate, dicyclohexyl fumarate and other fumarate diesters, butyl fumarate, propyl fumarate, ethyl fumarate and other fumarate monoesters, dibutyl maleate , Maleic acid diesters such as dipropyl maleate, diethyl maleate, butyl maleate, propyl maleate, ethyl maleate, dicyclohexyl maleic acid and other maleic acid monoesters, fumaric acid, dibasic acid such as mesaconic acid, styrene , Chlorostyrene, dichlorostyrene, bromostyrene, dibromostyrene, fluorostyrene, trifluorostyrene, nitrostyrene, cyanostyrene, α-methylstyrene, p-chloromethylstyrene, p-cyanostyrene, p-acetoxystyrene, p-chloride Stylylsulfonyl, ethyl p-styrenesulfonyl, methylp-styrenesulfonyl, propyl p-styrenesulfonyl, p-butoxystyrene, 2-vinylpyridine, 4-vinylpyridine, 3-isopropenyl-α, α'-dimethylbenzyl isocyanate, etc. Stylines, butyl vinyl ether, ethyl vinyl ether, 2-phenylvinyl alkyl ether, nitrophenyl vinyl ether, cyanophenyl vinyl ether, vinyl ethers such as chlorophenyl vinyl ether, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, acrylic acid. Pentyl, hexyl acrylate, decyl acrylate, lauryl acrylate, octyl acrylate, dodecyl acrylate, stearyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, bornyl acrylate, 2-ethoxyethyl acrylate, 2 acrylate -Butoxyethyl, 2-hydroxyethyl acrylate, tetrahydrofurfuryl acrylate, methoxyethylene glycol acrylate, ethyl carbitol acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 3- (trimethoxy) acrylate Cyril) propyl, polyethylene glycol acrylate, glycidyl acrylate, 2- (acryloyloxy) ethyl phosphate, 2,2,3,3-tetrafluoropropyl acrylate, 2,2,2-trifluoroethyl acrylate, acrylic acid Acrylic acid esters such as 2,2,3,3,3-pentafluoropropyl, acrylic acid 2,2,3,4,4,4-hexafluorobutyl, methyl methacrylate, t-butyl methacrylate, methacrylic acid s e c-butyl, i-butyl methacrylate, i-propyl methacrylate, decyl methacrylate, lauryl methacrylate, octyl methacrylate, dodecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, Bornyl methacrylate, benzyl methacrylate, Phenyl methacrylate, glycidyl methacrylate, polyethylene glycol methacrylate, 2-hydroxyethyl methacrylate, tetrahydrofurfuryl methacrylate, methoxyethylene glycol methacrylate, ethyl carbitol methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate , 2- (methacryloyloxy) ethyl phosphate, 2- (dimethylamino) ethyl methacrylate, 2- (diethylamino) ethyl methacrylate, 3- (dimethylaminopropyl, 2- (isocyanato) ethyl methacrylate) methacrylic Acrylic acid 2,4,6-tribromophenyl, me Tacrylate 2,2,3,3-tetrafluoropropyl, methacrylate 2,2,2-trifluoroethyl, methacrylate 2,2,3,3,3-pentafluoropropyl, methacrylate 2,2,3 Methacrylate esters such as 4,4,4-hexafluorobutyl, 1,3-butadiene, 2-methyl-1,3-butadiene, 2-chloro-1,3-butadiene, 2,3-dichloro-1, 3-butadiene, 2-cyano-1,3-butadiene, 1-chloro-1,3-butadiene, 2- (N-piperidylmethyl) -1,3-butadiene, 2-triethoxymethyl-1,3-butadiene , 2- (N, N-dimethylamino) -1,3-butadiene, N- (2-methylene-3-butenoyl) morpholine, 1,3-butadienes such as 2-methylene-3-butenylphosphonate diethyl, etc. , Acrylamide, methacrylic acid, sulfophenylacrylamide, sulfophenylitaconimide, acrylonitrile, methacrylonitrile, fumaronitrile, vinyl chloride, α-cyanoethyl acrylate, citraconic acid anhydride, vinyl acetic acid, vinyl propionate, vinyl pivalate, versamic acid Vinyl, acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, mono2- (methacryloyloxy) ethylphthalate, mono2- (methacryloyloxy) ethylsuccinate, mono2- (acryloyloxy) ethylsuccinate, methacryl Loxypropyltrimethoxysilane, methacryloxypropyldimethoxysilane, acrolein, diacetoneacrylamide, vinylmethylketone, vinylethylketone, diacetonemethacrylate, vinylsulfonic acid, isoprene sulfonic acid, allylsulfonic acid, 2-acrylamide-2-methylpropane Sulfonic acid, 2-acrylamide-1-methylsulfonic acid, 2-methacrylamide-2-methylpropanesulfonic acid, vinylpyrrolidone, dehydroalanine, sulfur dioxide, isobutene, N-vinylcarbazole, vinylidene dicyanide, paraquinodimethane, chlorotri Fluoroethylene, tetrafluoroethylene, norbornene, N-vinylcarbazole and the like can be mentioned. Among these, styrenes, acrylic acid esters, methacrylic acid esters, and N-substituted maleimides are preferable in consideration of copolymerizability with styrene sulfonate and availability.

The polymerization solvent used in the present invention is not particularly limited as long as it can uniformly dissolve the above-mentioned monomer mixture, but for example, water, methanol, ethanol, methoxyethanol, ethoxyethanol, propanol, 1-propanol, 2-. Alcohols such as propanol and ethylene glycol, methoxyethanol, ethoxyethanol, ethylene glycol monopropyl ether, 1-methoxy-2-propanol, 1,2-dimethoxypropane, propylene glycol monomethyl ether, 3-methoxy-3-methyl-1 -Butanol, 1 (or 2)-[2-methoxy (methyl) ethoxy] propanol, bis (3-hydroxypropyl) ether, bis (2-hydroxypropyl) ether, glycol ethers such as dipropylene glycol monomethyl ether, tetrahydrofuran , Ethers such as dioxane, esters such as 2-methoxy-1-methylethyl acetate and ethyl acetate, acetonitrile, acetone, N-methylpyrrolidone, dimethylformamide, dimethylsulfoxide, dimethylacetamide and the like, as well as mixed solvents thereof. Can be mentioned.

Examples of the radical polymerization initiator used in the present invention include di-t-butyl peroxide, dicumyl peroxide, t-butyl cumyl peroxide, benzoyl peroxide, dilauryl peroxide, cumene hydroperoxide, and t-. Butylhydroperoxide, 1,1-bis (t-butylperoxy) -3,5,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) -cyclohexane, cyclohexanone peroxide, t-butylper Oxybenzoate, t-butylperoxyisobutyrate, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisopropylcarbonate, Peroxide compounds such as cumyl peroxyoctate, potassium persulfate, ammonium persulfate, hydrogen peroxide, 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis ( 2,4-dimethylvaleronitrile), 2,2'-azobis (2-methylpropionitrile), 2,2'-azobis (2-methylbutyronitrile), 1,1'-azobis (cyclohexane-1- Carbonitrile), 1-[(1-cyano-1-methylethyl) azo] formamide, dimethyl 2,2'-azobis (2-methylpropionate), 4,4'-azobis (4-cyanovaleric acid) ), 2,2'-azobis (2,4,4-trimethylpentane), 2,2'-azobis {2-methyl-N- [1,1'-bis (hydroxymethyl) -2-hydroxyethyl] propion Amid}, 2,2'-azobis {2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2'-azobis {2- (2-imidazolin-2-yl) propane] disulfatedi Hydrate, 2,2'-azobis {2- [1- (2-hydroxyethyl) -2-imidazolin-2-yl) propane]} dihydrochloride, 2,2'-azobis (1-imino-1-) Pyrrolidino-2-methylpropane) dihydrochloride, 2,2'-azobis (2-methylpropionamidine) dihydrochloride, 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] Tetrahydrate, 1,1'-azobis (1-acetoxy-1-phenylmethane), 4,4'-dia Examples thereof include azo compounds such as Zendiylbis (4-cyanopentanoic acid) and α-hydro-ω-hydroxypoly (oxyethylene) polycondensate. Among these, when the living radical polymerization method is used, an azo-based initiator is preferable to a peroxide-based initiator from the viewpoint of controllability. When the above-mentioned peroxide-based polymerization initiator is used from the viewpoint of economy, ascorbic acid, erythorbic acid, aniline, tertiary amine, longalit, hydrosulfite, sodium sulfite, sodium hydrogen sulfite, and thiosulfite are used, if necessary. A reducing agent such as sodium or sodium hypophosphate can be used in combination.

The amount of the radical polymerization initiator used is usually 0.01 to 10 mol% with respect to all the monomers, and 0.01 to 5 mol% is more preferable in consideration of the purity of the target product.

The molecular weight regulator (chain transfer agent) used in the present invention is not particularly limited, and is, for example, thioglycolic acid, thioapple acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiosalicylic acid, 3-. Mercapto benzoic acid, 4-mercapto benzoic acid, thiomalonic acid, dithiosuccinic acid, thiomaleic acid, thiomaleic acid anhydride, dithiomaleic acid, thioglutaric acid, cysteine, homocysteine, 5-mercaptotetrazole acetate, 3-mercapto-1-propanesulfone Acid, 3-mercaptopropane-1,2-diol, mercaptoethanol, 1,2-dimethylmercaptoethane, 2-mercaptoethylamine hydrochloride, 6-mercapto-1-hexanol, 2-mercapto-1-imidazole, 3-mercapto -1,2,4-triazole, cysteine, N-acylcysteine, glutathione, N-butylaminoethanethiol, N, N-diethylaminoethanethiol and other mercaptans, diisopropylxanthogen disulfide, diethylxantogen disulfide, diethylthiuram disulfide, 2 , 2'-dithiodipropionic acid, 3,3'-dithiodipropionic acid, 4,4'-dithiodibutanoic acid, 2,2'-dithiobisbenzoic acid and other disulfides, iodoform and other halogenated hydrocarbons, benzyldithio Benzoate, 2-cyanoprop-2-yldithiobenzoate, 4-cyano-4- (thiobenzoylthio) pentanoic acid, 4-cyano-4- (dodecylsulfanylthiocarbonyl) sulfanylpentanoic acid, S, S-dibenzyltrithio Thiocarbonylthio compounds such as carbonate, 3-((((1-carboxyethyl) thio) carbonothio oil) thio) propanoic acid, cyanomethyl (3,5-dimethyl-1H-pyrazole) carbodithioate, α-iodobenzyl Alkiolated alkyl compounds such as cyanide, 1-iodoethylbenzene, ethyl2-iodo-2-phenylacetate, 2-iodo-2-phenylacetic acid, 2-iodopropanoic acid, 2-iodoacetic acid, diphenylethylene, p-chloro Examples thereof include diphenylethylene, p-cyanodiphenylethylene, α-methylstyrene dimer, organic tellurium compound, and sulfur. Among these, when it is desired to narrow the molecular weight distribution by living radical polymerization, a thiocarbonylthio compound or an alkyl iodide compound is preferable as a chain transfer agent from the viewpoint of controllability.

In the present invention, the polymerization temperature is 10 ° C. to 100 ° C., more preferably 40 ° C. to 90 ° C., and further preferably 60 ° C. to 90 ° C. from the viewpoint of the polymerization conversion rate, as in the case of ordinary radical polymerization.

The polymerization time is preferably 2 hours to 30 hours, more preferably 2 hours to 10 hours. In the case of polymerization by the sequential addition method, the time for continuous addition of the monomer mixture containing the molecular weight modifier and the polymerization initiator is usually 1 hour to 4 hours.

In the case of the above-mentioned living radical polymerization method, the polymerization proceeds while reversibly generating radicals from the Dormant species, and a runaway reaction is unlikely to occur. In some cases, it is preferable in terms of molecular weight controllability.

<Second manufacturing method>
Next, a second method for producing polystyrene sulfonic acid (or a salt thereof) will be described in detail.

In the second production method, for example, styrene and the above-mentioned carboxylic acid monomer are used in a non-halogen solvent such as toluene, benzene, xylene, methylcyclohexane, acetone, dioxane, methylethylketone, ethyl acetate, and tetrahydrofuran, 1,2-dichloroethane, chloroform, etc. This is a method for producing a carboxylic acid-modified polystyrene by dissolving a monomer mixture in a solvent capable of dissolving the monomer mixture, such as a halogen-based solvent such as 1,1,2-trichloroethane, and the above-mentioned radical polymerization method.

Since an organic solvent is used as the polymerization solvent in the second production method, a carboxylic acid anhydride monomer such as maleic anhydride or citraconic anhydride, which is difficult to use due to hydrolysis in an aqueous solvent, can also be used.

When a non-halogen solvent is used as the polymerization solvent, the polymer is isolated by forced drying of the polymerization solution or addition of a poor solvent, redissolved in the halogen-based solvent described above, and then with a sulfonate such as anhydrous sulfuric acid or fuming sulfuric acid. By sulfonated the styrene moiety in the polymer, a solution of the halogenated solvent containing the carboxylic acid-modified polystyrene sulfonic acid is obtained. An aqueous solution of carboxyl-modified polystyrene can be produced by injecting water into this and extracting the water-soluble carboxyl-modified polystyrene into the aqueous phase.

<Polystyrene sulfonic acid (or salt thereof) of the present invention>
The polystyrene sulfonic acid (or a salt thereof) of the present invention preferably has a weight average molecular weight of 5000 daltons (Da) to 4000 thousand daltons (Da) as measured by gel permeation chromatography (GPC). Further, considering the balance between curability and coatability, 20,000 Dalton (Da) to 1,000,000 Dalton (Da) are more preferable.

Next, polyoxazoline, which is a cross-linking agent of the present invention, will be described.

The polyoxazoline compound used in the present invention is a polymer containing a plurality of or a plurality of oxazoline groups in the polymer, and is particularly limited as long as it dissolves or disperses in the aqueous polystyrene sulfonic acid curable composition of the present invention. There is no.

For example, radically polymerizable oxazolines such as 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-isopropenyl-2-oxazoline and (meth) methoxypolyethylene glycol, (meth) acrylamide. , Polymers with (meth) acrylic monomers such as sodium (meth) acrylate (see, for example, JP-A-6-32844), oxazoline group-containing polymers (eg, manufactured by Nippon Catalyst Co., Ltd .; trade name Epocross (registered) See (trademark)).

Next, a hydrophilic solvent for suppressing thickening of the composition containing carboxyl-modified PSS and polyoxazoline and restoring fluidity will be described.

As described above, when a polymer containing a styrene sulfonic acid structural unit as a main component and a polyoxazoline compound are mixed as an aqueous solution, the viscosity is significantly increased and the fluidity is lost, which makes coating difficult. For unknown reasons, it is speculated that the viscosity is increased by the strong interaction between the benzenesulfonic acid (or salt thereof) structural unit of polystyrene sulfonic acid and the oxazoline structural unit. It is presumed that the hydrophilic solvent used in the present invention weakens the interaction and restores the fluidity.

Examples of the hydrophilic solvent used in the present invention include methoxyethanol, ethoxyethanol, ethylene glycol monopropyl ether, 1-methoxy-2-propanol, 1,2-dimethoxypropane, 2-methoxy-1-methylethyl acetate, and 2 acetate. -Methoxymethyl, propylene glycol monomethyl ether, 3-methoxy-3-methyl-1-butanol, 1 (or 2)-[2-methoxy (methyl) ethoxy] propanol, bis (3-hydroxypropyl) ether, bis (2) -Hydroxypropyl) ethers, glycol ethers such as dipropylene glycol monomethyl ether, methanol, ethanol, 1-propanol, 2-propanol, 1-methoxy-2-propanol, 1,2-propanediol, 1,3-propanediol , Alcohols such as 1,2-butanediol, and hydrophilic solvents such as tetrahydrofuran and acetone. Among these, ethanol, methoxyethanol, ethoxyethanol, 1-propanol, 1-methoxy-2-propanol, propylene glycol monomethyl ether, and 1,2-dimethoxypropane are more preferable from the viewpoint of fluidity and transparency of the composition.

In the present invention, the concentration of the hydrophilic solvent in the polystyrene sulfonic acid curable composition is 10 wt% to 70 wt% with respect to the total solvent. If it is less than 10 wt%, the effect of suppressing thickening may not be sufficiently obtained, and if it is more than 70 wt%, the solubility of polystyrene sulfonic acid (or a salt thereof) may decrease, and problems such as clouding of the composition may occur. .. Further, from the viewpoint of the thickening suppressing effect and the transparency of the composition, 20 wt% to 50 wt% is more preferable.

Further, in order to promote the cross-linking reaction of carboxyl-modified PSS by polyoxazoline, the polystyrene sulfonic acid curable composition of the present invention is catalyzed with an amine salt of an acidic compound such as diammonium phosphate, ammonium chloride or ammonium paratoluenesulfonate. May be added as. The amount of the catalyst added is usually preferably 0.1 wt% to 5 wt% with respect to the carboxyl-modified PSS.

The polystyrene sulfonic acid curable composition of the present invention is applied to the surface of various substrates or coated on the surface of fibers, and then the solvent is removed by air drying, vacuum drying or heat drying, and then the temperature is 60 ° C to 150 ° C. By heating, a cured film of polystyrene sulfonic acid can be formed on the surface of the base material or the fiber. Since water inhibits the cross-linking reaction at high temperature, when the polymer content in the composition is low, it is preferable to remove the water to some extent at low temperature and then heat the composition.

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

<Analysis of Polymer by Gel Permeation Chromatography (GPC)>
The raw material monomer and the polymer were quantified (area%) using HLC-8320 manufactured by Tosoh Corporation. The sample was dissolved in water or acetonitrile or a mixed solvent thereof to prepare a 0.1 wt% solution, and GPC measurement was performed under the following conditions. From the peak area (a) derived from the monomer and the peak area (b) derived from the polymer, the conversion rate of the polymer was calculated by the following formula.
Polymer conversion rate (% of area) = 100 × [1- {a / (a + b)}]
Column = TSK Guard column AW-H + TSK AW6000 + TSK AW3000
Eluent = sodium sulfate aqueous solution (0.05 mol / L) / acetonitrile = 90/10 (Vol ratio) solution Flow velocity / injection amount / column temperature = 0.6 ml / min, injection amount = 10 μl, column temperature = 40 ° C.
Detector = UV detector (wavelength 230 nm)
Calibration curve = standard polystyrene sulfonate (manufactured by Sowa Kagaku) was used to prepare from the peak top molecular weight and elution time.

<Viscosity measurement of polystyrene sulfonic acid curable composition>
The measurement was performed at room temperature using a Brookfield viscometer LVDV2T (manufactured by Eiko Seiki Co., Ltd.).

<Evaluation of curability of polystyrene sulfonic acid>
By collecting 4 to 5 g of the polystyrene sulfonic acid curable composition on an aluminum plate (diameter 13 cm) of an infrared moisture meter (FD-720 manufactured by Kett Science Institute Co., Ltd.), spreading it thinly, and heating and drying it at 120 ° C. for 30 minutes. A dried product of the polystyrene sulfonic acid composition was obtained.
0.4 to 0.5 g of the dried product was precisely weighed in a 100 ml glass standard bottle (= weight A), about 90 ml of pure water was added, and the mixture was sealed and shaken at room temperature for 3 days using a shaker.
The solution shaken for 3 days was filtered off with a 100-mesh SUS wire mesh (= weight B) whose weight was measured in advance, and then 100 ml of pure water was poured into the gel on the wire mesh for washing. The excess water was wiped off with an industrial paper wiper, and the weight (= weight C) of the wire mesh containing the water swelling gel was measured.
The wire mesh containing the water swelling gel was air-dried for 3 days, and then vacuum-dried at 110 ° C. for 5 hours using a vacuum dryer to measure the weight (= weight D).
The gel content and water swelling degree of polystyrene sulfonic acid were calculated from the following formula.
Gel content (wt%) = 100 × (DB) / A
Water swelling degree (wt%) = 100 × (CB) / (DB)

<Reagents used>
The compounds described in the examples used the following, but the present invention is not limited by these examples.
Sodium parastyrene sulfonate; manufactured by Tosoh Finechem Co., Ltd. (purity 89.1%)
Lithium parastyrene sulfonate; manufactured by Toso Finechem Co., Ltd. Ammonium parastyrene sulfonate; manufactured by Toso Finechem Co., Ltd. Methacrylic acid; manufactured by Fujifilm Wako Junyaku Co., Ltd., special grade acrylic acid; manufactured by Fujifilm Wako Junyaku Co., Ltd., special grade 2-Hydroxyethyl methacrylate; manufactured by Fujifilm Wako Junyaku Co., Ltd., first-class 2,2'-azobis- (2-amidinopropane) dihydrochloride; manufactured by Fujifilm Wako Junyaku Co., Ltd. (trade name V-50)
3-Mercapto-1,2-propanediol; Wako Pure Chemical Industries, Ltd. Epocross (registered trademark) WS-700 (Nippon Shokubai Co., Ltd. water-soluble polyoxazoline, non-volatile content 24.9 wt%, functional group concentration 4. 5 mmol / g-resin content)
Epocross (registered trademark) WS-500 (water-soluble polyoxazoline manufactured by Nippon Shokubai Co., Ltd., non-volatile content 38.9 wt%, functional group concentration 4.5 mmol / g-resin content)
Epocross (registered trademark) WS-300 (water-soluble polyoxazoline manufactured by Nippon Shokubai Co., Ltd., non-volatile content 10.2 wt%, functional group concentration 7.7 mmol / g-resin content)

Synthesis Example 1 Production of polystyrene sulfonic acid (PSS-1) 52.00 g of pure water was charged into a 1 L glass four-necked flask equipped with a reflux condenser, a nitrogen introduction tube, and a paddle-type stirrer, and 85 in a nitrogen atmosphere. Heated in an oil bath at ° C. Here, a separately prepared sodium parastyrene sulfonate aqueous solution [100.00 g of sodium parastyrene sulfonate and 4.15 g of methacrylic acid were dissolved in 451.66 g of pure water, and deoxidized treatment was repeated by repeating depressurization and introduction of nitrogen by an aspirator. Initiator aqueous solution [2,2'-azobis- (2-amidinopropane) dihydrochloride 0.19 g dissolved in 30.20 g of pure water] is added dropwise over 200 minutes for 180 minutes. went. After the completion of dropping the initiator, the bath temperature was raised to 90 ° C. and aged for 2 hours as it was to obtain an aqueous solution of sodium polystyrene sulfonate (PSS-1) containing a carboxyl group. The polymerization conversion rate of each monomer was 100%.

The polymer concentration in the aqueous solution calculated from the charge was 14.61 wt%, and the content of the carboxylic acid monomer structural unit with respect to the total of the sulfonic acid monomer structural unit and the carboxylic acid monomer structural unit in the polymer was 10.1 mol%, which was determined by GPC. The number average molecular weight of the polymer was 242,500 (Da), the weight average molecular weight was 586200 (Da), the pH (normal temperature) was 5.4, and the solution viscosity measured by the B-type viscometer was 460 mPa · s.

Synthesis Example 2 Production of polystyrene sulfonic acid (PSS-2) 61.00 g of pure water was charged into a 2 L glass four-necked flask equipped with a reflux condenser, a nitrogen introduction tube, and a paddle-type stirrer, and 85 in a nitrogen atmosphere. Heated in an oil bath at ° C. Here, a separately prepared sodium parastyrene sulfonate aqueous solution [270.00 g of sodium parastyrene sulfonate and 102.50 g of methacrylic acid was dissolved in 1101.70 g of pure water, and deoxidized treatment was repeated by repeating depressurization and introduction of nitrogen by an aspirator. Initiator aqueous solution [2,2'-azobis- (2-amidinopropane) dihydrochloride in 5.64 g dissolved in pure water 39.77 g] was added dropwise over 200 minutes for 180 minutes. went. After completion of the dropping of the initiator, the bath temperature was raised to 90 ° C. and aged for 2 hours as it was to obtain an aqueous solution of sodium polystyrene sulfonate (PSS-2) containing a carboxyl group. The polymerization conversion rate of each monomer was 100%.

The polymer concentration in the aqueous solution calculated from the charge was 21.70 wt%, and the content of the carboxylic acid monomer structural unit with respect to the total of the sulfonic acid monomer structural unit and the carboxylic acid monomer structural unit in the polymer was 50.62 mol%, which was determined by GPC. The number average molecular weight of the polymer was 75100 (Da), the weight average molecular weight was 164200 (Da), the pH (normal temperature) was 4.3, and the solution viscosity measured by the B-type viscometer was 78 mPa · s.

Synthesis Example 3 Production of polystyrene sulfonic acid (PSS-3) 52.00 g of pure water was charged into a 1 L glass four-necked flask equipped with a reflux condenser, a nitrogen introduction tube, and a paddle-type stirrer, and 85 in a nitrogen atmosphere. Heated in an oil bath at ° C. Here, a separately prepared sodium parastyrene sulfonate aqueous solution [100.00 g of sodium parastyrene sulfonate and 5.60 g of acrylic acid were dissolved in 451.66 g of pure water, and deoxidation treatment was performed by repeating depressurization and introduction of nitrogen by an aspirator. Initiator aqueous solution [2,2'-azobis- (2-amidinopropane) dihydrochloride 0.19 g dissolved in pure water 30.50 g] is added dropwise over 200 minutes for 180 minutes. went. After completion of the dropping of the initiator, the bath temperature was raised to 90 ° C. and aged for 2 hours as it was to obtain an aqueous solution of sodium polystyrene sulfonate (PSS-3) containing a carboxyl group. The polymerization conversion rate of each monomer was 100%.

The polymer concentration in the aqueous solution calculated from the charge was 16.08 wt%, and the content of the carboxylic acid monomer structural unit with respect to the total of the sulfonic acid monomer structural unit and the carboxylic acid monomer structural unit in the polymer was 15.11 mol%, which was determined by GPC. The number average molecular weight of the polymer was 261200 (Da), the weight average molecular weight was 605600 (Da), the pH (normal temperature) was 4.6, and the solution year measured with a B-type viscometer was 650 mPa · s.

Synthesis Example 4 Production of polystyrene sulfonic acid (PSS-4) 52.00 g of pure water was charged into a 1 L glass four-necked flask equipped with a reflux condenser, a nitrogen introduction tube, and a paddle-type stirrer, and 85 in a nitrogen atmosphere. Heated in an oil bath at ° C. Here, a separately prepared aqueous solution of sodium parastyrene sulfonate [100.00 g of sodium parastyrene sulfonate, 4.15 g of methacrylic acid, and 3.15 g of 2-hydroxyethyl methacrylate are dissolved in 465.00 g of pure water, and the pressure is reduced by an aspirator. Deoxidized by repeating introduction of nitrogen] for 180 minutes, an aqueous initiator solution [0.12 g of 2,2'-azobis- (2-amidinopropane) dihydrochloride dissolved in 30.21 g of pure water] The polymerization was carried out while dropping the mixture over 200 minutes. After completion of the dropping of the initiator, the bath temperature was raised to 90 ° C. and aged for 2 hours as it was to obtain an aqueous solution of sodium polystyrene sulfonate (PSS-4) containing a carboxyl group. The polymerization conversion rate of each monomer was 100%.

The polymer concentration in the aqueous solution calculated from the charge is 14.73 wt%, and the carboxyl group-containing monomer structural unit relative to the total of the sulfo group-containing monomer structural unit, the carboxyl group-containing monomer structural unit and the carboxyl group-free monomer structural unit in the polymer. The content is 9.56 mol%, and the content of the carboxyl group-free monomer structural unit is 4 with respect to the total of the sulfo group-containing monomer structural unit, the carboxyl group-containing monomer structural unit and the carboxyl group-free monomer structural unit in the polymer. It was .80 mol%.

The number average molecular weight of the polymer determined by GPC was 324,000 (Da), the weight average molecular weight was 759000 (Da), the pH (normal temperature) was 5.3, and the solution viscosity measured by a B-type viscometer was 690 mPa · s. ..

Comparative Example 1 Preparation and evaluation of PSS-1 curable composition 51.12 g (carboxyl group content 3.87 mmol) of PSS-1 (solution viscosity 460 mPa · s) obtained in Synthesis Example 1 and aqueous polyoxazoline (Nippon Catalyst Co., Ltd.) 3.63 g (oxazoline group content 3.28 mmol) manufactured by Epocross (registered trademark) WS-700 was collected in 100 and 200 ml glass standard bottles and stirred vigorously with a spatula to prepare an aqueous polystyrene sulfonate curable composition. This composition was vigorously thickened and had poor fluidity (solution viscosity 74,300 mPa · s) so that it could be wrapped around a spatula (Weissenberg effect).

Pure water was added to the composition to dilute it (the resin content decreased), but no significant decrease in viscosity was observed, and the fluidity did not recover (see Table 1). Although the composition after heat-drying was gelled (cured), it is difficult to apply it to various substrates, and it is clear that the composition is not suitable as the curable composition of the present invention.
Only PPS-1 was dried under the same conditions, and the gel content was measured and found to be 0%.

Example 1 Preparation and evaluation of PSS-1 curable composition 51.12 g (carboxyl group content 3.87 mmol) of PSS-1 (aqueous solution) obtained in Synthesis Example 1 and aqueous polyoxazoline (Epocross manufactured by Nippon Catalyst Co., Ltd. (registered) 3.63 g (oxazoline group content 3.28 mmol) of WS-700) was collected in 100 and 200 ml glass standard bottles and stirred vigorously with a spatula to prepare an aqueous polystyrene sulfonate curable composition. This composition had a high viscosity and poor fluidity as it wrapped around the spatula (Weisenberg effect), but when 1-propanol, which is a kind of hydrophilic solvent, was added instead of water (the resin content decreased). , The ratio of hydrophilic solvent in all solvents increased), the viscosity decreased, and the fluidity was greatly restored.

As a result of evaluating the curability of the polystyrene sulfonic acid composition containing 1-propanol, a water-insoluble gel was obtained in high yield. It was also confirmed that the curability did not change even after at least 7 hours had passed since the composition was prepared. It is clear that the composition is a polystyrene sulfonic acid composition having good coatability and curability on various substrates (see Table 1).

Example 2 Preparation and evaluation of PSS-1 curable composition In Example 1, even if 1-methoxy-2-propanol was added instead of 1-propanol, the viscosity was similarly reduced and the fluidity was greatly restored.
As a result of evaluating the curability of the polystyrene sulfonic acid composition containing 1-methoxy-2-propanol, a water-insoluble gel was obtained in high yield. It was also confirmed that the curability did not change even after at least 7 hours had passed since the composition was prepared. It is clear that the composition is a polystyrene sulfonic acid composition having good coatability and curability on various substrates (see Table 1).

Example 3 Preparation and evaluation of PSS-1 curable composition In Example 1, even if 1,2-dimethoxypropane was added instead of 1-propanol, the viscosity was similarly reduced and the fluidity was greatly restored.
As a result of evaluating the curability of the polystyrene sulfonic acid composition containing 1,2-dimethoxypropane, a water-insoluble gel was obtained in high yield. It was also confirmed that the curability did not change even after at least 7 hours had passed since the composition was prepared. It is clear that the composition is a polystyrene sulfonic acid composition having good coatability and curability on various substrates (see Table 1).

Comparative Example 2 Preparation and evaluation of PSS-2 curable composition 51.12 g (carboxyl group content 38.55 mmol) of PSS-2 (solution viscosity 78 mPa · s) obtained in Synthesis Example 2 and aqueous polyoxazoline (Nippon Catalyst Co., Ltd.) 10.00 g (oxazoline group content 24.90 mmol) manufactured by Epocross (registered trademark) WS-700 was collected in 100 and 200 ml glass standard bottles and stirred vigorously with a spatula to prepare an aqueous polystyrene sulfonate curable composition. This composition was vigorously thickened and had poor fluidity (solution viscosity 23,100 mPa · s) so that it could be wrapped around a spatula (Weissenberg effect).

Pure water was added to the composition to dilute it, but no significant decrease in viscosity was observed, and the fluidity did not recover (see Table 1). Although the composition after heat-drying was gelled (cured), it is difficult to apply it to various substrates, and it is clear that the composition is not suitable as the curable composition of the present invention.
Only PPS-2 was dried under the same conditions, and the gel content was measured and found to be 0%.

Example 4 Preparation and evaluation of PSS-2 curable composition 51.12 g (carboxyl group content 38.55 mmol) of PSS-2 (aqueous solution) obtained in Synthesis Example 2 and aqueous polyoxazoline (Epocross manufactured by Nippon Catalyst Co., Ltd. (registered) 10.00 g (oxazolline group content 24.90 mmol) of WS-700) was collected in 100 and 200 ml glass standard bottles and stirred vigorously with a spatula to prepare an aqueous polystyrene sulfonic acid curable composition. This composition was so viscous that it wrapped around a spatula (Weisenberg effect) and had poor fluidity, but when 1-methoxy-2-propanol, which is a kind of hydrophilic solvent, was added instead of water, the viscosity became high. Decreased and liquidity recovered significantly.

As a result of evaluating the curability of the polystyrene sulfonic acid composition containing 1-methoxy-2-propanol, a water-insoluble gel was obtained in high yield. It was also confirmed that the curability did not change even after at least 7 hours had passed since the composition was prepared. It is clear that the composition is a polystyrene sulfonic acid composition having good coatability and curability on various substrates (see Table 1).

Comparative Example 3 Preparation and evaluation of PSS-3 curable composition 51.12 g (carboxyl group content 6.75 mmol) of PSS-3 (solution viscosity 650 mPa · s) obtained in Synthesis Example 3 and aqueous polyoxazoline (Nippon Catalyst Co., Ltd.) 4.50 g (oxazoline group content 74.76 mmol) manufactured by Epocross (registered trademark) WS-700 was collected in 100 and 200 ml glass standard bottles and stirred vigorously with a spatula to prepare an aqueous polystyrene sulfonate curable composition. This composition was vigorously thickened and had poor fluidity (solution viscosity 88,700 mPa · s) so that it could be wrapped around a spatula (Weissenberg effect).

Pure water was added to the composition to dilute it, but no significant decrease in viscosity was observed, and the fluidity did not recover (see Table 1). Although the composition after heat-drying was gelled (cured), it is difficult to apply it to various substrates, and it is clear that the composition is not suitable as the curable composition of the present invention.
Only PPS-3 was dried under the same conditions, and the gel content was measured and found to be 0%.

Example 5 Preparation and evaluation of PSS-3 curable composition 51.12 g (carboxyl group content 6.75 mmol) of PSS-3 (aqueous solution) obtained in Synthesis Example 3 and aqueous polyoxazoline (Epocross manufactured by Nippon Catalyst Co., Ltd. (registered) 4.50 g (oxazoline group content 74.76 mmol) of WS-700) was collected in 100 and 200 ml glass standard bottles and stirred vigorously with a spatula to prepare an aqueous polystyrene sulfonic acid curable composition. This composition was so viscous that it wrapped around a spatula (Weisenberg effect) and had poor fluidity, but when 1,2-dimethoxypropane, which is a kind of hydrophilic solvent, was added instead of water, the viscosity became high. It declined and liquidity recovered significantly.

As a result of evaluating the curability of the polystyrene sulfonic acid composition containing 1,2-dimethoxypropane, a water-insoluble gel was obtained in high yield. It was also confirmed that the curability did not change even after at least 7 hours had passed since the composition was prepared. It is clear that the composition is a polystyrene sulfonic acid composition having good coatability and curability on various substrates (see Table 1).

Example 6
In Example 4, even if ethoxyethanol was added instead of 1,2-dimethoxypropane, the viscosity was similarly reduced and the fluidity was greatly restored.
As a result of evaluating the curability of the polystyrene sulfonic acid composition containing ethoxyethanol, a water-insoluble gel was obtained in high yield. It was also confirmed that the curability did not change even after at least 7 hours had passed since the composition was prepared. It is clear that the composition is a polystyrene sulfonic acid composition having good coatability and curability on various substrates (see Table 1).

Comparative Example 4 Preparation and evaluation of PSS-4 curable composition 51.12 g (carboxyl group content 3.77 mmol) of PSS-4 (solution viscosity 690 mPa · s) obtained in Synthesis Example 4 and aqueous polyoxazoline (Nippon Catalyst Co., Ltd.) 3.15 g (oxazoline group content 3.53 mmol) manufactured by Epocross (registered trademark) WS-700 was collected in 100 and 200 ml glass standard bottles and stirred vigorously with a spatula to prepare an aqueous polystyrene sulfonate curable composition. This composition was vigorously thickened and had poor fluidity as it wrapped around the spatula (Weisenberg effect) (solution viscosity 101,300 mPa · s).

Pure water was added to the composition to dilute it, but no significant decrease in viscosity was observed, and the fluidity did not recover (see Table 1). Although the composition after heat-drying was gelled (cured), it is difficult to apply it to various substrates, and it is clear that the composition is not suitable as the curable composition of the present invention.
Only PPS-4 was dried under the same conditions, and the gel content was measured and found to be 0%.

Example 7 Preparation and evaluation of PSS-4 curable composition 51.12 g (carboxyl group content 3.77 mmol) of PSS-4 (aqueous solution) obtained in Synthesis Example 4 and aqueous polyoxazoline (Epocross manufactured by Nippon Catalyst Co., Ltd. (registered) 3.15 g (oxazoline group content 3.53 mmol) of WS-700) was collected in 100 and 200 ml glass standard bottles and stirred vigorously with a spatula to prepare an aqueous polystyrene sulfonic acid curable composition. This composition had a high viscosity and poor fluidity as it wrapped around a spatula (Weisenberg effect), but when ethanol, which is a kind of hydrophilic solvent, was added instead of water, the viscosity decreased and the fluidity decreased. Has recovered significantly.

As a result of evaluating the curability of the polystyrene sulfonic acid composition containing ethanol, a water-insoluble gel was obtained in high yield. It was also confirmed that the curability did not change even after at least 7 hours had passed since the composition was prepared. It is clear that the composition is a polystyrene sulfonic acid composition having good coatability and curability on various substrates (see Table 1).

The aqueous polystyrene sulfonic acid curable composition of the present invention comprises polystyrene sulfonic acid (or a salt thereof) modified with a general-purpose monomer such as (meth) acrylic acid, a polymer containing a plurality of oxazoline groups, and hydrophilicity having a specific structure. It is an aqueous curable composition containing a sex solvent, and has excellent coatability (fluidity) and curability. The formed polystyrene sulfonic acid cured film is an anionic electrolyte membrane, and is extremely useful in a wide range of industrial fields such as modification of the surface of various equipment and coating of carbon materials.

Claims (6)

An aqueous polystyrene sulfonic acid curable composition containing the following components (A) to (D).
(A) Including the structural unit (a) represented by the following general formula (1) and the structural unit (b) represented by the general formula (2), with respect to the total of the structural unit (a) and the structural unit (b). molar ratio of 2 mol% to 60 mol% der of the structural unit (b) is, weight average molecular weight determined by gel permeation chromatography 160,000 daltons (Da) ~4000000 daltons (Da) a is polystyrene sulfonic acid structural units ( a);
General formula (1)

(In the formula (1), M ₁ represents a proton, an ammonium ion, a quaternary ammonium cation, a quaternary phosphonium cation, an alkali metal cation or an alkaline earth metal cation). And structural unit (b);
General formula (2)

(Equation (2), Q ₁ represents a radical polymerizable monomer residue having a carboxyl group.) A carboxyl group-containing monomer structural unit represented by,
(B) A polymer containing a plurality of oxazoline groups,
(C) A hydrophilic solvent selected from the group consisting of glycol ethers and alcohols having 1 to 4 carbon atoms, or a combination of two or more kinds, and (D) water (provided that the above component (A) and (B) are used. The compounding ratio of the components is 10: 2 to 2:10 in terms of the equivalent ratio of the carboxyl group and the oxazoline group, and the compounding ratio of the components (A) and (B) to the total amount of the components (A) to (D) is It is 0.5 wt% to 30 wt%, and the blending ratio of the component (C) to the total amount of the component (C) and the component (D) is 10 wt% to 70 wt%). ) An aqueous polystyrene sulfonic acid curable composition containing the following components (A'), (B), (C) and (D).
(A') The structural unit (a) represented by the following general formula (3), the structural unit (b) represented by the general formula (4), and the structural unit (c) represented by the general formula (5). Including, the molar ratio of the structural unit (b) to the total of the structural unit (a), the structural unit (b) and the structural unit (c) is 2 mol% to 60 mol%, and the structural unit (a) and the structural unit ( The molar ratio of the structural unit (c) to the total of b) and the structural unit (c) is 1 mol% to 30 mol%, and the weight average molecular weight determined by gel permeation chromatography is 160000 daltons (Da) to 4000 thousand daltons (Da) to 4000 thousand daltons (da). Da) Polystyrene sulfonic acid structural unit (a);
General formula (3)

(In the formula (3), M ₁ represents a proton, an ammonium ion, a quaternary ammonium cation, a quaternary phosphonium cation, an alkali metal cation or an alkaline earth metal cation).
Structural unit (b);
General formula (4)

(. Equation (4), Q ₁ is representative of the radical polymerizable monomer residue having a carboxyl group) carboxyl group-containing monomer structural units represented by, and the structural unit (c);
General formula (5)

(Equation (5) in, Q ₂ represents. A radical polymerizable monomer residues containing no carboxyl group) polymers comprising structural units (B) a plurality of oxazoline groups in the monomers that do not contain a carboxyl group represented by,
(C) A hydrophilic solvent selected from the group consisting of glycol ethers and alcohols having 1 to 4 carbon atoms, or a combination of two or more kinds, and (D) water (provided that the above (A') component and (B). The blending ratio of the component) is 10: 2 to 2:10 in terms of the equivalent ratio of the carboxyl group to the oxazoline group, with respect to the total amount of the component (A'), the component (B), the component (C) and the component (D). The blending ratio of the component (A') and the component (B) is 0.5 wt% to 30 wt%, and the blending ratio of the component (C) to the total amount of the components (C) and (D) is 10 wt% to 70 wt%. ). ) Q ₁ is methacrylic acid (salt) residues, acrylic acid (salt) residue, maleic acid (salt) residues, citraconic acid (salt) residue, at least one selected from the group consisting of itaconic acid (salt) residues The aqueous polystyrene citraconic acid curable composition according to claim 1 or claim 2, which is a radically polymerizable monomer residue which is a species or a combination of two or more kinds. Q ₂ is a styrene residue, consisting of methyl methacrylate residues, 2-hydroxyethyl residues methacrylate, and at least one or more combinations selected from the group consisting of methacrylamide residues and N- phenyl maleimide residue The aqueous polystyrene sulfonic acid curable composition according to claim 2, which is a radically polymerizable monomer residue. Glycol ethers are methoxyethanol, ethoxyethanol, ethylene glycol monopropyl ether, 1-methoxy-2-propanol, 1,2-dimethoxypropane, 2-methoxy-1-methylethyl acetate, 2-methoxymethyl acetate, propylene glycol monomethyl. Ether, 3-methoxy-3-methyl-1-butanol, 1 (or 2)-[2-methoxy (methyl) ethoxy] propanol, bis (3-hydroxypropyl) ether, bis (2-hydroxypropyl) ether and di The aqueous polystyrene sulfonic acid curable composition according to claim 1 or 2, which is at least one selected from the group consisting of propylene glycol monomethyl ether. A water-insoluble polystyrene sulfonate cured product represented by the following general formula (6), which is formed from the aqueous polystyrene sulfonic acid curable composition according to any one of claims 1 to 5.
General formula (6)

(In the formula (6), M ₁ is the same as the above formula (1), Q ₁ is the same as the above formula (4), and Q ₃ is a polymer having a plurality of oxazoline groups which is the above component (B). Represents the main chain of. N, m and k represent integers greater than or equal to 1.)