WO2002053835A1

WO2002053835A1 - Papermaking additive, process for producing papermaking additive, and paper containing papermaking additive

Info

Publication number: WO2002053835A1
Application number: PCT/JP2001/011467
Authority: WO
Inventors: Akihiro Sato; Masayuki Hiroi; Masatomi Ogawa
Original assignee: Japan Pmc Corporation
Priority date: 2000-12-27
Filing date: 2001-12-26
Publication date: 2002-07-11
Also published as: JPWO2002053835A1; JP4158145B2

Abstract

A papermaking additive which brings about excellent drainage, excellent yield, and enhanced paper strength even when the effect of enhancing paper strength is difficult to obtain because the pH of the pulp slurry to be subjected to sheet formation fluctuates due to fluctuations in feed material quality, and because of impurity inclusion due to feed material deterioration and of an increase in the amount of fine fibers, etc.; and a process for producing the papermaking additive. The process comprises adding a polymerization initiator to a monomer mixture (A) comprising (a) a (meth)acrylamide, (b) a vinyl monomer having a carboxyl group and/or a sulfo group and a salt of the monomer, (c) a vinyl monomer having a tertiary or quaternary amino group, and (d) a crosslinking monomer to initiate polymerization and, at the time when 20 to 96% of the monomer mixture (A) has reacted, dropping a monomer solution (B) containing at least one of the monomers (a), (b), (c), and (d) to further conduct polymerization.

Description

Description Papermaking additives, manufacturing method of papermaking additives, and paper containing papermaking additives

The present invention relates to a papermaking additive, a method for producing the papermaking additive, and a paper containing the papermaking additive.Specifically, the present invention relates to a papermaking system in the acidic, neutral, or alkaline region, and excellent drainage. , A paper additive of a polyacrylamide copolymer capable of enhancing the yield and paper strength, a method for producing the paper additive, and various strengths such as burst strength and internal bond strength using the paper additive. About high paper. Background art

Conventionally, in the papermaking process, various papermaking additives have been used in order to improve productivity due to speeding up of a paper machine or to improve paper quality. Above all, paper strength agents are important chemicals for improving paper quality and productivity, and the range of their use is expanding more and more, and chemicals are being improved. Polyacrylamide copolymers are widely used as paper strength agents, and are classified into anionic, cationic and amphoteric copolymers from the viewpoint of their ionicity. First, in the 1960s, anionic polyacrylamide copolymers began to be used in combination with sulfate bands. Then, in the 1970's and 80's, Mannich-modified acrylamide-based polymers and Hoffman-modified acrylamide-based polymers into which cationic properties were introduced came to be used for the purpose of improving drainage and yield. However, these modified acrylamide-based polymers have poor product stability, and the Mannich-modified acrylamide-based polymer has a problem that the product contains formalin. Then, from the 1980s, anionic and cationic vinyl compounds were added. Amphoteric polyacrylamide copolymers copolymerized with acrylamide have been used (Japanese Patent Application Laid-Open No. 60-94697). The amphoteric polyacrylamide-based copolymer is used alone or in combination with an anionic polyacrylamide-based copolymer. The polyacrylamide-based copolymer has been produced by adding a polymerization initiator to a monomer solution at a predetermined temperature and performing polymerization. In recent years, polymerization methods have been improved to enhance the paper strength of polyacrylamide copolymers. For example, a method in which polyacrylamide is synthesized in advance and a monomer solution of acrylamide is polymerized in the presence of the polyacrylamide (Japanese Patent Application Laid-Open No. 3-224845), or a method in which polyacrylamide is added to a monomer such as acrylamide A method of introducing a graft structure by dropping and polymerizing (JP-A-5-195485) is disclosed. These methods have the disadvantage that productivity is poor because polyacrylamide is synthesized in advance and then acrylamide is further polymerized. Further, a method is disclosed in which a monomer containing a monomer having a crosslinkable substituent in a side chain is dropped and polymerized to promote branching / crosslinking in a polymer, thereby increasing the molecular weight and improving paper strength. (Japanese Unexamined Patent Publication Nos. Hei 7-13359-99, Hei 7-188531, Japanese Unexamined Patent Publication No. 11-228641, Hei 8-6771 No. bulletin). Furthermore, a method for improving the performance by continuously synthesizing an anionic polyacrylamide copolymer and a cationic polyacrylamide copolymer by two-stage drop polymerization to form a so-called ion complex is disclosed. (Japanese Unexamined Patent Publication No. Hei 6-199795, Japanese Unexamined Patent Publication No. Hei 7-199797). However, in recent years, fluctuations in the pH of pulp slurry during papermaking due to fluctuations in the quality of papermaking raw materials, an increase in the amount of waste paper used, the contamination of contaminants with the progress of closed systems, and an increase in fine fibers For this reason, conventional polyacrylamide-based copolymer papermaking additives cannot provide sufficient effects. Under these circumstances, further improvement of papermaking additives is required to improve productivity and paper strength. The present invention relates to fluctuations in pH of pulp slurry during papermaking and deterioration of papermaking raw materials. Papermaking additives that exhibit an excellent paper strength enhancement effect even in situations where it is difficult to obtain a paper strength enhancement effect due to the inclusion of contaminants accompanying the above, an increase in the conductivity of papermaking white water, and an increase in fine fibers, etc. It is intended to provide a manufacturing method. Disclosure of the invention

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, when producing a paper additive of a polyacrylamide copolymer, after starting the polymerization of monomers, a specific reaction was started. When the rate reached the rate, it was found that the remaining monomers were added and polymerized to obtain a papermaking additive excellent in paper strength enhancing effect, and the present invention was completed. That is, the present invention, which is means for solving the above problems, comprises (1) (a) (meth) acrylamide, (b) a vinyl monomer having a carboxylic acid group and a 7 or sulfonic acid group and salts thereof, and (c) 3 A polymerization initiator is added to a vinyl monomer having a quaternary amino group or a quaternary ammonium salt, and (d) a monomer containing a crosslinkable monomer, and after polymerization is initiated, the monomer (A) When the conversion reaches 20 to 96.5%, (a) (meth) acrylamide, (b) a vinyl monomer having a carboxyl group and a Z or sulfonic acid group and salts thereof, and (c) a tertiary amino A vinyl monomer having a group or a quaternary ammonium salt, and (d) a monomer (B) containing at least one kind of a crosslinkable monomer, a method for producing a papermaking additive by dropping and polymerizing,

(2) The method for producing the papermaking additive according to the above (1), wherein the monomer (B) to be dropped in the above (1) comprises (b) a vinyl monomer having a hydroxyl group and / or a sulfonic acid group and salts thereof. ,

(3) The method for producing a papermaking additive according to (1), wherein the monomer (B) to be dropped in (1) is a vinyl monomer having (c) a tertiary amino group or a quaternary ammonium salt.

(4) The monomer (B) dropped in (1) is (b) a carboxyl A vinyl monomer having a group and / or a sulfonic acid group and salts thereof, and (c) a method for producing the papermaking additive according to the above (1), which comprises a vinyl monomer having a tertiary amino group or a quaternary ammonium salt,

(5) The monomer (B) to be dropped in the above (1) is (a) a (meth) acrylamide, (b) a vinyl monomer having a carbonyl group and / or a sulfonic acid group and salts thereof, A) a vinyl monomer having a tertiary amino group or a quaternary ammonium salt, and (d) a method for producing the papermaking additive according to (1) above, which comprises a crosslinkable monomer;

(6) Papermaking according to any one of (1) to (5), wherein the monomer (B) is dropped and polymerized when the reaction rate of the monomer (A) reaches 30 to 90%. Manufacturing method of additives for

(7) The method for producing a papermaking additive according to any one of (1) to (6), wherein the polymerization is performed in the presence of a urea compound.

(8) a papermaking additive comprising the copolymer produced by the production method according to any one of (1) to (7),

And (9) a paper containing the papermaking additive of (8). BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail. The present invention relates to a method for adding a polymerization initiator to a monomer (A) containing the monomers (a) to (d),

When the conversion of (A) reaches 20 to 96.5%, a monomer (B) containing at least one monomer of the components (a) to (d) is further added dropwise. The present invention relates to a method for producing a papermaking additive to be polymerized. (A) The (meth) acrylamide that can be used in the present invention is acrylamide or methacrylamide, and these can be used in the form of a powder or an aqueous solution. Examples of (b) vinyl monomers having a hydroxyl group that can be used in the present invention include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, fumaric acid, maleic acid, and itacone. Unsaturated dicarboxylic acids such as acid, citraconic acid and muconic acid, unsaturated tricarboxylic acids such as aconitic acid, 3-butene-1,2,3-tricarboxylic acid and 4-pentene-1,2,4-tricarboxylic acid; No. Examples of the vinyl monomer having a sulfonic acid group include vinyl sulfonic acid, styrene sulfonic acid, (meth) aryl sulfonic acid, 2-acrylamide-2-methylpropanesulfonic acid, and 2-acrylamide-2-phenylpropanesulfonic acid. Fonic acid and the like. Examples of the salt of a vinyl monomer having a carboxylic acid group and a salt of a vinyl monomer having a sulfonic acid group include a vinyl monomer having a carboxyl group, an alkali metal salt of a vinyl monomer having a sulfonic acid group, and an alkaline earth. Metal salts and ammonium salts. These may be used alone or in combination of two or more. Examples of (c) vinyl monomers having a tertiary amino group that can be used in the present invention include dimethylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, and the like. And dialkylaminoalkyl (meth) acrylates such as dimethylaminopropyl (meth) acrylate, and dialkylaminoalkyl (meth) acrylamides such as dimethylaminopropyl (meth) acrylamide and dimethylaminopropyl (meth) acrylamide And the inorganic acid salts such as hydrochloride and sulfate of the vinyl monomer having a tertiary amino group, and the organic acid salts such as formate and acetate of the vinyl monomer having a tertiary amino group. Examples of the vinyl monomer having a quaternary ammonium salt include a vinyl monomer obtained by reacting the vinyl monomer having a tertiary amino group with a quaternizing agent. Examples of the quaternizing agent include alkyl halides such as methyl chloride and methyl bromide, benzyl chloride, and benzyl bromide. Aralkyl halide, dimethyl sulfate, getyl sulfate, epichlorohydrin, 3-chloro-2-hydroxypropyltrimethylammonium chloride, glycidyltrialkylammonium chloride and the like. These vinyl monomers having a tertiary amino group or a quaternary ammonium salt may be used alone or in combination of two or more. In the present invention, (d) the crosslinkable monomer includes, for example, difunctional (meth) acrylates, bis (meth) acrylamides, divinyl esters, and other difunctional monomers, trifunctional monomers, and tetrafunctional monomers. And polyfunctional monomers such as monomers. These may be used alone or in combination of two or more. As the component (d), other than the above, a water-soluble aziridinyl compound, a water-soluble polyfunctional epoxy compound, a silicon-based compound, and the like can also be used. These may be used alone or in combination of two or more. May be used in combination. Examples of the di (meth) acrylates include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, and glycerin diacrylate. Examples thereof include (meth) acrylates, which may be used alone or in combination of two or more. Examples of the bis (meth) acrylamides include Ν, Ν′-methylenebis (meth) acrylamide, ethylenebis (meth) acrylamide, hexamethylenebis (meth) acrylamide, and Ν, N′-bisacrylamideacetic acid , Ν, N'-methyl bisacrylamidoacetate, Ν, Ν-benzylidenebisacrylamide, N, N'-bis (acrylamidomethylene) urea and the like. These may be used alone. Alternatively, two or more kinds may be used in combination. Examples of the divinyl esters include divinyl adipate, divinyl sebacate, diaryl phthalate, diaryl maleate, and diaryl succinate, and these may be used alone. Two or more kinds may be used in combination. Other bifunctional monomers include: For example, acryl (meth) acrylate, dibibenzene, diisopropenylbenzene, N-methylolacrylamide, N, N-dimethyl (meth) acrylamide, N, N-getyl (meth) acrylamide, diaryldimethylammonium Plume salt, diarylamine, diarylchlorendate, glycidyl (meth) acrylate, silicon compounds, etc., may be used alone or in combination of two or more. Is also good. Examples of the trifunctional monomer include triacryl formal, triaryl isocyanurate, N, N-diarylacrylamide, N, N-diaryl methacrylamide, triallylamine, triallyl trimellitate, and the like. May be used alone or in combination of two or more. Examples of the tetrafunctional monomer include tetramethylol methane tetraacrylate, tetraaryl pyromellitate, N, N, N ', N'-tetraaryl-1,4-diaminobutane, tetraarylamine salt, and tetraaryl And the like. These may be used alone or in combination of two or more. Examples of the water-soluble aziridinyl compound include tetramethylolmethane tri-β-aziridinylpropionate, trimethylolpropane monotree aziridinylpropionate, 4,4′-bis (ethyleneiminecarbonylamino Diphenylmethane and the like can be mentioned, and these may be used alone or in combination of two or more. Examples of the water-soluble polyfunctional epoxy compound include (poly) ethylene glycol diglycidyl ether, (poly) propylene glycol diglycidyl ether, (poly) glycerin diglycidyl ether,

(Poly) glycerin triglycidyl ether and the like can be mentioned. These may be used alone or in combination of two or more. Examples of the silicon-based compound include 3- (meth) acryloxypropyltrimethoxysilane and 3- (meth) acryloxypropyltrimethoxysilane. (Meth) acryloxypropyldimethoxymethylsilane, 3- (meth) acryloxypropyltrimethoxysila

Chlorosilane, 3- (meth) a

3 — (Meth) acryloxy 2

And vinyldimethylacetoxysilane. These may be used alone or in combination of two or more. In the present invention, the monomer (A) or the monomer (B) may be a monomer other than the above-mentioned monomers (a) to (d) (hereinafter referred to as “component (e)”). ) Can also be used. Examples of the component (e) include a nonionic vinyl monomer. Examples of the nonionic vinyl monomer include N-substituted (meth) acrylamide, (meth) acrylic ester, (meth) acrylonitrile, styrene, styrene derivative, biel acetate, pinyl propionate, and methyl vinyl ether. These may be used alone or in combination of two or more. Examples of the N-substituted (meth) acrylamide include N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-dimethyl-methacrylacrylamide, N —Isopropyl (meth) acrylamide and N-t-octyl (meth) acrylamide. Examples of the urea compound in the present invention include urea, guanidyl urea phosphate, sulfate and the like. These may be used alone or in combination of two or more. Among them, urea is preferred. Urea compounds are polymerized in addition to monomers (A), monomers (B) or both. Some of the urea compounds may be added after polymerization. Further, the entire amount of the urea compound may be added after the completion of the polymerization, but it is desirable to add the urea compound to the monomer (A) in view of the paper strength enhancing effect. New The amount of each of the components (a) to (d) in the monomers (A) is determined based on the amount of paper used when paper is manufactured using the paper additive containing the obtained polyacrylamide copolymer. The paper strength, such as internal bond strength and burst strength, and the performance of drainage, fine fibers, fillers, and other properties during papermaking can be sufficiently considered. From the viewpoint of paper strength, the component (a) is usually 99.795 to 55% by mole, preferably 97.9 to 79% by mole, and (b) to 100% by mole of the total of (a) to (d). Component power 0.1 to 20% by mole, preferably 1 to 10% by mole, component (c) is usually 0.1 to 20% by mole, preferably 1 to 10% by mole, and component (d) is usually 0.005%. 55 mol%, preferably 0.01-1 mol%. The other monomer (e) which can be copolymerized with the monomers (a) to (d) can be used in an amount of 5 mol% or less. The monomer (B) to be dropped during the polymerization may be a monomer containing at least one of the components (a) to (d). Among them, a monomer solution containing the component (b) alone, a monomer solution containing the component (c) alone, a monomer solution containing the components (b) and (c), the above (a) and (b) ), And a monomer solution containing the components (c), and a monomer solution containing the components (a) to (d) are preferable. The amount of the urea compound to be added is preferably not more than 30% by weight, more preferably not more than 10% by weight, based on the weight of all monomers. By carrying out the polymerization of the present invention in the presence of a urea compound, a polyacrylamide copolymer having more excellent effects such as paper strength can be synthesized. Further, the present invention also has a feature that by adding these urea compounds, the viscosity stability of the papermaking additive is improved. As the polymerization initiator used in the present invention, conventionally known and commonly used polymerization initiators can be used. Specifically, persulfates such as sodium persulfate, potassium persulfate, ammonium persulfate, etc .; peroxides such as benzoyl peroxide, hydrogen peroxide, tert-butyl hydroperoxide, g-tert-butyl peroxide; Bromates such as sodium bromate and potassium bromate, perborates such as sodium perborate and ammonium perborate, and percarbonates such as sodium percarbonate, potassium percarbonate and ammonium percarbonate Superphosphates such as sodium, potassium and ammonium perphosphates can be used. In this case, one kind may be used alone, or two or more kinds may be used in combination. Further, it may be used in combination with a reducing agent to be used as a redox polymerizing agent. Examples of the reducing agent include sulfites such as sodium sulfite, bisulfites such as sodium bisulfite, organic amines such as Ν, ,, Ν ′, Ν′-tetramethylethylenediamine, and reducing sugars such as aldose. Can be mentioned. One of these reducing agents may be used alone, or two or more thereof may be used in combination. In addition to the above, azobisisobutyronitrile, 2,2'-azobis-1-amidinopropane hydrochloride, 2,2'-azobis-1,2,4'-dimethylvaleronitrile, 4,4: azobis-4 —Azo-based polymerization initiators such as cyanovaleric acid and salts thereof can also be used. Usually, a polymerization initiator is added to a monomer solution (で) to start polymerization. However, a part of the polymerization initiator may be added during the polymerization for the purpose of reducing the residual monomer. If necessary, a conventionally known chain transfer agent can be appropriately used in combination with the monomers (Α) and the monomers (Β). Conventionally known chain transfer agents include compounds having one or more hydroxyl groups in the molecule, such as ethanol, isopropyl alcohol, butanol, ethylene glycol, glycerin alcohols, polyethylene oxide, polyglycerin, etc. Examples include oligomers and polymers, sugars such as glucose, ascorbic acid, and sucrose, and vitamins. Compounds containing one or more mercapto groups in the molecule include, for example, butylmercaptan, butane, mercaptoethanol, thioglycolic acid and esters thereof, and mercapto. Examples include topropionic acid and its esters, thioglycerin, cysteamine and its salts. Compounds having one or more carbon-carbon unsaturated bonds in the molecule include, for example, (meth) aryl alcohol and its ester derivative, (meth) arylamine, diarylamine, dimethallylamine and its amide derivative, Examples thereof include triarylamine, trimethallylamine, (meth) arylsulfonic acid and salts thereof, arylsulfides, and arylmercaptans. Furthermore, hypophosphorous acid can be mentioned. The synthesis of the polyacrylamide copolymer in the present invention is usually carried out as follows. First, in an atmosphere of an inert gas such as nitrogen, a monomer (A), water as a solvent (an organic solvent may be used in combination), and the above-mentioned chain transfer agent if necessary in a predetermined reaction vessel. Under charging and stirring, the polymerization initiator is added to initiate polymerization. Next, when the reaction rate of the monomer (A) (hereinafter, sometimes referred to as “comparison”) reaches 20 to 96.5%, preferably 30 to 90%. When reaching, drop monomer (B). After the addition, the mixture is further heated and polymerized to obtain the polyacrylamide copolymer of the present invention. The conversion is carried out using the type and amount of each of the components (a) to (d) in the monomer (A) and the monomer (B), and a papermaking additive containing the obtained polyacrylamide copolymer. When paper is manufactured by using paper, the paper strength is determined within the above range, taking into account the paper strength such as internal bond strength and bursting strength, and the performance such as drainage during papermaking and the yield of fine fibers and fillers. be able to. When the conversion is not within the above range, the above-mentioned performance in the case where paper is produced using the obtained papermaking additive containing the polyacrylamide copolymer is not sufficient. Assuming that the total of the monomer (A) and the monomer (B) is 100 mol%, the amount of the monomer (B) to be dropped is usually when the monomer (B) does not contain the component (a). 0.1 to 40 mol%, preferably 1 to 20 mol%, and the monomers (B) When it contains the component (a), it is usually from 10 to 70 mol%, preferably from 20 to 60 mol%. The dropping time is usually 5 to 60 minutes, preferably 10 to 30 minutes. When the monomers (B) are composed of a plurality of monomer components, they may be dropped as a mixture of a plurality of monomers, or each monomer may be dropped individually. The polymerization temperature is not particularly limited as long as it is within a range where ordinary radical polymerization occurs, but is usually performed in the range of 50 to 95 ° C. As a method of measuring the conversion, a conventionally known technique, for example, as described in “Experimental method of polymer synthesis, (Takayuki Otsu, Masayoshi Kinoshita)” can be used. Is the value measured by ¹ H-NMR

The solids content of the polyacrylamide-based copolymer synthesized by polymerization is usually 5 to 30% by weight, and the viscosity at 25 ° C. measured with a Brookfield rotational viscometer is usually 20. O mP a · s or less. In the present invention, since the monomers (B) are dropped and polymerized during the polymerization of the monomers (A), a method of polymerizing a monomer solution of acrylamides in the presence of a polyacrylamide-based copolymer is used. It is possible to produce a polyacrylamide-based copolymer in a shorter time as compared with a conventional method such as a method of dropping and polymerizing the entire amount of a monomer. It is unknown why the polyacrylamide-based copolymer produced according to the present invention is superior to the polyacrylamide-based copolymer produced by a conventional method, such as paper strength, but it is dropped during the polymerization. Therefore, first, a relatively low-molecular-weight acrylamide-based polymer is formed, and then the polyacrylamide-based copolymer is increased in molecular weight by abstraction of hydrogen in the polymer by a polymerization initiator radical remaining in the polymerization system. This may be because the branched polymer is easily formed and the ion balance can be optimized. The papermaking additive containing the polyacrylamide-based copolymer produced by the present invention exerts a paper strength enhancing effect by being added to the pulp slurry when producing paper. Pulp raw materials such as kraft pulp and sulfite pulp, or bleached unbleached chemical pulp, shredded pulp, mechanical pulp and thermomechanical pulp, or unbleached high-yield pulp, and used newspapers, magazines, and corrugated paper Both recycled paper pulp such as recycled paper and deinked waste paper can be used. The papermaking additive containing the polyacrylamide-based copolymer produced according to the present invention is less affected by the conductivity of the parv slurry than the conventional papermaking additive, and especially the conductivity of the parv slurry is 800 ^. There is a large difference in performance from conventional papermaking additives at S / cm or more. Further, in order to express physical properties required for each paper type, other papermaking additives can be used in combination with the papermaking additive produced by the present invention. Other papermaking additives to be used in combination include, for example, fillers, dyes, rosin-based sizing agents for acidic papermaking, mouth gin-based sizing agents for neutral papermaking, alkylketene dimer-based sizing agents, and alkenylsuccinic anhydride-based sizing agents. Acid, neutral and alkaline papermaking sizing agents such as specially modified rosin-based sizing agents, wet paper strength improvers, retention improvers, drainage improvers, bulking agents, defoamers, etc. . These may be used alone or in combination of two or more. Examples of the filler include clay, talc, titanium oxide, heavy or light calcium carbonate, and the like. The papermaking additive of the present invention may contain the polyacrylamide-based copolymer synthesized according to the present invention alone, or may be an anionic polyacrylamide-based copolymer or a Mannich-modified acrylamide-based polymer. , A Hoffman-modified acrylamide-based polymer, a sulfate band, and the like. The papermaking additive of the present invention may be used alone, or may be an anionic polyacrylamide copolymer. Or a Mannich-modified acrylamide-based polymer, a Hoffman-modified acrylamide-based polymer, or a sulfate band. Paper containing the polyacrylamide-based copolymer of the present invention can be obtained by, for example, papermaking using the above-described papermaking additive of the present invention. Examples of the obtained paper include PPC paper and inkjet recording paper. , Laser printer paper, foam paper, art paper, cast paper, high quality coated paper and other printing information paper, photographic paper, kraft paper, packaging paper such as pure white roll paper, other note paper, book paper, printing Paper, paperboard such as newsprint, paperboard for paper containers such as manila pole, white ball, chipball, high-grade whiteboard, liner, core paper, paper core paper, etc.

(Example)

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. In addition,% is based on weight unless otherwise indicated. Unless otherwise indicated, the mol% indicates a value when the total of the monomers (A) and the monomers (B) is 100 mol%.

(Synthesis of polyacrylamide copolymer)

Example 1 (Synthesis method in which monomer B is composed of component (b))

In a 1-liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 413.36 g of water and 305.39 g of a 50% aqueous solution of acrylamide as a monomer (A) (89.62 mol) %), 11.30 g (3.0 mol%) of dimethylaminoethyl methacrylate, 26.85 g (3.0 mol%) of a 76% aqueous solution of methacryloyloxyshetyl dimethyl pentane ammonium chloride, and 1.87 g (0.6 mol%) of conic acid, 28.05 g (0.37 mol%) of 5% aqueous sodium methallylsulfonate, 2.38 g (1.0 mol) of N, Ν'-dimethylacrylamide %) And 11.95 g (0.01 mol%) of 0.5% triacrylformal, and adjusted to pH 2.5 with a 30% aqueous sulfuric acid solution. Then, nitrogen gas The temperature was raised to 60 ° C. in a gas atmosphere, 5.77 g of a 5% aqueous solution of ammonium persulfate was added, and the temperature was raised to 80 ° C. in 20 minutes. When the conversion of these first-stage monomers (monomer (A)) reached 33%, an aqueous monomer solution (B) consisting of 179.24 g of water and 7.48 g (2.4 mol%) of itaconic acid was converted to an aqueous monomer solution (B). It was added dropwise over 20 minutes, and polymerization was carried out at 80 ° C. When the estimated viscosity at 25 ° C reached 6,000 to 8,000 mPa · s, the reaction was stopped by cooling. A polymer solution with a solid content of 20.3%, a pH of 3.3, and a viscosity (25 ° C, using a Brookfield rotational viscometer) of 7,300 mPa's was obtained. In this example, ^ H-NMR measurement was performed on the copolymer sampled immediately before the dropping of the monomer (B), and the conversion was calculated from the intensity ratio of the peak derived from the monomer and the polymer. Examples 2 to 6 (Synthesis method in which monomer B is composed of component (b))

The conversion of monomer (A) and dropping ratio of itaconic acid (in monomer (A) and in Z monomer (B)) when dropping monomer solution (B) were changed. Except for this, the procedure was the same as in Example 1. Table 1 shows the conversion, the method of adding itaconic acid (divisional addition ratio), and the properties of the obtained polyacrylamide copolymer. Comparative Example 1

In a 1 liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 592.26 g of water, 305.39 g of 50% aqueous acrylamide solution (89.62 mol%), dimethylaminoethyl 1.30 g (3.0 mol%) of methacrylic acid, 26.85 g (3.0 mol%) of a 76% aqueous solution of methacryloyloxetyl dimethylbenzylammonium chloride, itaconic acid 9. 35 g (3.0 mol%), 5% aqueous sodium methallylsulfonate solution 28.05 g (0.37 mol%), N, N'-dimethylacrylamide 2.38 g (1.0 mol%), 0. 11.95 g (0.01 mol%) of 5% triacryl formal was charged and adjusted to PH 2.5 with a 30% aqueous sulfuric acid solution. Then, the temperature was raised to 60 ° C. in a nitrogen gas atmosphere, 5.77 g of a 5% aqueous solution of ammonium persulfate was added, the temperature was raised to 80 ° C. in 20 minutes, and polymerization was carried out at 80 ° C. as it was. When the estimated viscosity at 25 ° C reached 6,000 to 8,000 OmPa · s, the reaction was stopped by cooling. A polymer solution having a solid content of 20.2%, a pH of 3.4, and a viscosity of 7,120 mPa · s (at 25 ° C., using a Brookfield rotational viscometer) was obtained.

(Monomer: Synthetic method in which B is composed of component ( _b ))

Example 7

In a 1-liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 413.40 g of water, 60.0 g of isopropyl alcohol, and 346.96 g of a 50% aqueous solution of acrylamide (9 1.29 mol%), 76% methacryloyloxyshethyl dimethyl pendant ammonium chloride aqueous solution 1.3.9 g (1.4 mol%), fumaric acid 4.03 g (1.3 mol%), 0.5 % Triacrylic formal 13.33 g (0.01 mol%) was charged. Then, the temperature was raised to 60 ° C in a nitrogen gas atmosphere, 4.88 g of a 5% aqueous solution of ammonium persulfate was added, and the temperature was raised to 80 ° C in 20 minutes. When the conversion of the first-stage monomer (monomer (A)) reaches 35%, a monomer aqueous solution consisting of 128.79 g of water and 14.45 g (6. Omol%) of 80% acrylylic acid is added. It was added dropwise over 20 minutes, and polymerization was carried out at 80 ° C for 2 hours. When the estimated viscosity at 25 ° C reached 5, OOO to 7,000 mPas, the reaction was stopped by cooling. Solid content 20.3%, DH3.3, viscosity (Using a Brookfield rotational viscometer at 25 ° C.) A polymer solution of 6, 36 OmPa · s was obtained. Examples 8 to 11 (Synthesis of monomer (B) consisting of component (b))

A synthesis reaction was carried out in the same manner as in Example 7, except that the monomers (A), the monomers (B), and the chain transfer agent were changed as shown in Table 2. Table 3 shows the properties of the obtained polyacrylamide copolymer. Comparative Examples 2, 3

A synthesis reaction was carried out in the same manner as in Comparative Example 1, except that the monomers (A) and the chain transfer agent were changed as shown in Table 2. Table 3 shows the properties of the obtained polyacrylamide copolymer.

Two

(Synthesis method in which monomer (B) is composed of component (b))

The numbers in the table are ¾%

'Acid, i A ... acid,

TAF- · -Triacryl forma ■ IPA… iso 7 ° ϋP)) 1'co-] MET… Met

Table 3

(Synthesis method in which monomer (B) is composed of component (b))

Example 12 (Synthesis method in which monomer B is composed of component (c))

In a 1-liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 494.15 g of water and 305.06 g of a 50% aqueous solution of acrylamide as a monomer (A) (90.62 mol) %), 76% aqueous solution of acryloyloxyshethyl dimethyl pendant ammonium chloride 25.22 g (3.0 mol%), itaconic acid 9.24 g (3.0 mol%), 5% methallyl Sodium sulfonate aqueous solution 27.71 g (0.37 mol%), N, N'-dimethylacrylamide 2.35 g (1.0 mol%), 0.5% triacrylformal 11.81 g (0.01 Mol%). Then, the temperature was raised to 60 ° C. in a nitrogen gas atmosphere. 10.80 g of a 5% aqueous solution of ammonium persulfate was added, polymerization was started, and the temperature was raised to 85 ° C. When the conversion of these first-stage monomers (monomer (A)) reaches 20.4%, 90.08 g of water and 76% acryloyloxyethyl dimethyl pendant ammonium chloride aqueous solution are added. An aqueous monomer solution (B) consisting of 81 g (2.0 mol%) was added dropwise over 20 minutes, and the temperature was maintained at 80 ° C. When the estimated viscosity at 25 ° C reaches 6,000-9,000 mPa's, The reaction was stopped by cooling. A polymer solution with a solid content of 20.4%, pH 3.2, and viscosity (25 ° C, using a Brookfield rotational viscometer) of 6, 24 OmPas was obtained. Examples 13 to 20 (Synthesis method in which monomer B comprises component (c))

Conversion of monomer (A) when dropping monomer solution (B), and split addition ratio of 76% acryloyloxhetyldimethylbenzylammonium chloride (in monomer (A) / monomer (In (B)), except that Example 7 was changed. Table 4 shows the conversion, the split addition ratio of 76% acryloyloxyshethyl dimethyl pendant ammonium chloride, and the properties of the obtained polyacrylamide copolymer. Comparative Example 4

In a 1-liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 536.89 g of water, 305.06 g of a 50% aqueous acrylamide solution (90.62 mol%), 76% 42.03 g (5.0 mol%) of an aqueous solution of cryloyloxetyldimethylbenzylammonium chloride, 9.24 g (3.0 mol%) of itaconic acid, 27.71 g of a 5% aqueous solution of sodium methallylsulfonate ( 0.37 mol%), 2.35 g (1.0 mol%) of N, N, -dimethylacrylamide, and 11.81 g (0.01 mol%) of 0.5% triacrylformal were charged. Otherwise, the synthesis reaction was carried out in the same manner as in Comparative Example 1 to obtain a polymer solution having a solid content of 20.2%, a pH of 3.3, and a viscosity (25 ° C, using a Brookfield rotational viscometer) of 8,20 OmPa · s. Was.

Table 4

(Synthesis method where monomer is composed of component (c))

DABz- ■■ ϋ ϋ ^^) W me 1 '>

Example 21 (Synthesis method in which monomer is composed of components (b) and (c))

In a 1-liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 603.53 g of water and 266.43 g of a 50% aqueous solution of acrylamide as a monomer (A) (94.28 mol %), Dimethylaminoethyl methacrylate 8.44 g (2.7 mol%), itaconic acid 4.97 g (1.92 mol%), 5% sodium methallylsulfonate aqueous solution 18.55 g ( (0.30 mol%) and 19.82 g (0.02 mol%) of 0.5% triacrylformal were adjusted to pH 2.5 with 30% sulfuric acid. Next, the temperature was raised to 60 ° C. in a nitrogen gas atmosphere. 4.54 g of a 5% aqueous solution of ammonium persulfate was added, polymerization was started, and the temperature was raised to 85 ° C. When the concentration of these first-stage monomers (monomer (A)) reaches 30.2%, 73.79 g of water and dimethylaminoethyl methacrylate A monomer aqueous solution (B) consisting of 0.94 g (0.30 mol%) of relate and 1.24 g (0.48 mol%) of itaconic acid was added dropwise over 20 minutes, and the temperature was maintained at 80 ° C.

When the estimated viscosity at 25 ° C became 7,000 to 8,000 mPa · s, the reaction was stopped by cooling. A polymer solution having a solid content of 15.4%, pH of 3.5, and viscosity (25 ° C, using a Brookfield rotational viscometer) of 7,90 OmPa · s was obtained. Examples 22 to 23 (Synthesis method in which monomer B is composed of components (b) and (c)) Except that the conversion of monomer (A) when dropping monomer (B) was changed, Performed as in Example 21. Table 5 shows the compatibility of the monomer (A) at the time of dropping and the properties of the obtained polyacrylamide copolymer. Comparative Example 5

In a 1-liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 675.32 g of water, 266.46 g of a 50% aqueous acrylamide solution (9.4.28 mol%), dimethylaminoethyl Methacrylate 9.38 g (3.0 mol%), itaconic acid 6.21 g (2.4 mol%), 5% sodium methallylsulfonate aqueous solution 18.55 g (0.30 mol%), 0 .82 g (0.02 mol%) of 5% triacryl formal was charged and adjusted to 1 12.5 with 30% sulfuric acid. Otherwise, the synthesis reaction was performed in the same manner as in Comparative Example 1. Table 5 shows the properties of the obtained polyacrylamide copolymer.

Table 5

(Monomer: Synthesis method in which B is composed of components (b) and (c))

Example 24 (Synthesis method in which monomer より comprises components (a), (b), (c), and (d))

In a 1-liter four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen gas inlet tube, 382.80 g of water and 198.60 g of a 50% aqueous acrylamide aqueous solution (56.24 mol %), Dimethylaminoethyl methyl acetate 4.69 g (1.2 mol%), itaconic acid 7.27 g (2.25 mol%), 5% sodium methallylsulfonate aqueous solution 23.57 g ( (0.30 mol%) and 3.83 g (0.01 mol%) of 1% N, N methylenebisacrylamide were adjusted to pH 3.0 with 30% sulfuric acid. Next, the temperature was raised to 60 ° C. in a nitrogen gas atmosphere. 4.54 g of a 5% aqueous solution of ammonium persulfate was added, polymerization was started, and the temperature was raised to 85 ° C. When the conversion of these first-stage monomers (monomer (A)) reaches 21.0%, 196.63 g of water, 130.27 g (36.89 mol%) of 50% aqueous acrylamide solution, 76% 25.97 g (2.8 mol%) of methacryloyloxydimethyldimethylbenzylammonium chloride aqueous solution, 0.81 g (0.25 mol%) of itaconic acid, 5% aqueous solution of sodium methallylsulfonic acid 3 A monomer aqueous solution (B) consisting of 93 g (0.05 mol%) and 3.83 g (0.01 mol%) of 1% N, N methylenebisacrylamide was added dropwise over 20 minutes, and 80 ° C For 20 minutes. In addition, a 5% aqueous solution of ammonium persulfate 9. 06 g was added, and the mixture was kept at 80 ° C as it was. When the estimated viscosity at 25 ° C reached 6,000 to 9,000 mPa's, the reaction was stopped by cooling. A polymer solution having a solid content of 20.4%, a pH of 3.6, and a viscosity (25 ° C., using a Brookfield rotational viscometer) of 6,50 OmPa · s was obtained. Examples 25 to 29 (Synthesis method in which monomer B comprises components (a), (b), (c), and (d))

Example 24 was carried out in the same manner as in Example 24 except that the conversion of the monomer (A) at the time of dropping the monomer (B) was changed. Table 6 shows the conversion of the monomers (A) at the time of dropping and the properties of the obtained polyacrylamide copolymer. Comparative Example 6

In a 1-liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 579.43 g of water, 328.87 g of a 50% aqueous acrylamide solution (9.3.13 mol%), dimethylaminoethyl Methacrylate 4.69 g (1.2 mol%), 76% aqueous acryloyloxhetyl dimethylbenzylammonium chloride aqueous solution 25.97 g (2.8 mol%), itaconic acid 8.08 g ( 2.5 mol%), 5% aqueous sodium methallylsulfonate solution 27.50 g (0.35 mol%), 1% N, N methylenebisacrylamide 7.66 g (0.02 mol%) The pH was adjusted to 3.0 with 30% sulfuric acid. Otherwise, the synthesis reaction was performed in the same manner as in Comparative Example 1. Table 6 shows the properties of the obtained polyacrylamide copolymer. Comparative example Ί

Example 24 was carried out in the same manner as in Example 24 except that the conversion of the monomer (A) at the time of dropping the monomer (B) was changed to 15%. Table 6 shows the conversion of monomer (A) at the time of dropping and the properties of the obtained polyacrylamide copolymer. Example 30 (Synthesis method containing urea)

In a 1-liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 382.80 g of water, 9.96 g of urea as a monomer (A), and 188.68 of a 50% aqueous acrylamide solution g (56.24 mol%), dimethylaminoethyl methacrylate 4.69 g (1.2 mol%), itaconic acid 7.27 g (2.25 mol%), 5% aqueous sodium methallylsulfonate solution 23.57 g (0.30 mol%) and 3.83 g (0.01 mol%) of 1% N, N methylenebisacrylamide were added, and the pH was adjusted to 3.0 with 30% sulfuric acid. Next, the temperature was raised to 60 ° C. in a nitrogen gas atmosphere. 5.38 g of a 5% aqueous solution of ammonium persulfate was added, polymerization was started, and the temperature was raised to 85 ° C. When the conversion of these first-stage monomers (monomer class (A)) reaches 90.3%, 227.12 g of water, 123.77 g (36.89 mol%) of 50% aqueous acrylamide solution, 76% 25.97 g (2.8 mol%) of methacryloyloxetyl dimethylbenzylammonium chloride aqueous solution, 0.81 g (0.25 mol%) of itaconic acid, 3.93 g of 5% aqueous solution of sodium methallyl sulfonate (0.05 mol%) and 3.83 g (0.01 mol%) of a monomer aqueous solution containing 1% N, N-methylenebisacrylamide were cooled to 80 ° C and kept at 80 ° C. When the estimated viscosity at 25 ° C reached 6,000 to 9,000 mPa's, the reaction was stopped by cooling. Solid content: 20.3%, pH: 3.6, viscosity (25 ° (using a Brookfield rotational viscometer): 6, 45 OmPa · s polymer solution was obtained. Example 31 (Synthesis method containing urea)

Example 30 was carried out in the same manner as in Example 30, except that the conversion of the monomer (A) at the time of dropping the monomer (B) was changed. Table 6 shows the conversion of the monomers (A) at the time of dropping and the properties of the obtained polyacrylamide copolymer. Comparative Example 8

4-liter 1-liter port with stirrer, thermometer, reflux condenser, and nitrogen gas inlet In a flask, 418.35 g of water, 197.64 g (56.24 mol%) of a 50% aqueous acrylamide solution as monomer (A), 4.66 g (1.2 mol%) of dimethylaminoethyl methacrylate, Itaconic acid 7.24 g (2.25 mol%), 5% sodium methallylsulfonate aqueous solution 23.57 g (0.30 mol%), 1% N, N methylenebisacrylamide 3.81 g (0.01 Mol%) and adjusted to pH 3.0 with 30% sulfuric acid. Next, the temperature was raised to 40 ° C. in a nitrogen gas atmosphere. 7.90 g of a 10% aqueous solution of ammonium persulfate and 4.63 g of a 10% aqueous solution of sodium bisulfite were added, and the polymerization was started and the temperature was raised to 85 ° C. After polymerization at 85 ° C for 2 hours, separately charged water 127.60 g 50% aqueous acrylamide solution 129.64 g (36.89 mol%), 76% methacryloyloxydimethyldimethylbenzylammonium chloride Aqueous solution 25.85 g (2.8 mol%), itaconic acid 0.80 g (0.25 mol%), 5% sodium methallylsulfonate aqueous solution 3.91 g (0.05 mol%), 1% 3.81 g (0.01 mol%) of N, N methylenebisacrylamide and 44.57 g of a 3% aqueous solution of potassium persulfate were added dropwise over 1 hour. After completion of dropping, keep the temperature at 85 ° C for 1 hour, and solid polymer 20.4%, pH 4.3, viscosity (25 ° (: using Brookfield rotational viscometer) 5,50 OmPa · s polymer One solution was obtained Comparative Example 9

In a beaker, 310.55 g (93.13 mol%) of a 50% aqueous solution of acrylamide, 4.42 g (1.2 mol%) of dimethylaminoethyl methacrylate, 76% aqueous solution of methacryloyloxetyl dimethylbenzylammonium chloride 24.52 g (2.8 mol%), itaconic acid 7.64 g (2.5 mol%), 5% sodium methallylsulfonate aqueous solution 25.97 g (0.35 mol%), 1% N, N 7.24 g (0.02 mol%) of methylenebisacrylamide was charged and adjusted to pH 4.5 to prepare a monomer A solution. In a 1-liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 496.85 g of water was charged, and adjusted to pH 4.5 with 1% sulfuric acid. The temperature was raised to C. Then, the monomer The 1A solution, 61.55 g of a 1% aqueous solution of ammonium persulfate, and 61.27 g of a 0.2% aqueous solution of sodium bisulfite were continuously dropped into the reaction vessel over 70 minutes. During dropping, the internal temperature was kept at 50 ° C. After completion of the dropwise addition, a polymerization reaction was further performed at 50 ° C for 110 minutes. Solid content 20.4%, ρΗ3.8, viscosity (25 ° C, using Brookfield rotary viscometer) 5, 05 OmPas Was obtained. Comparative Example 10

In a beaker, 49.65 g of water, 19.42 g (5.82 mol%) of 50% aqueous acrylamide solution, 7.63 g (2.5 mol%) of itaconic acid, 5% aqueous solution of sodium methallylsulfonate 25. 99 g (0.35 mol%) was charged, and the pH was adjusted to 4.5 with a 30% aqueous sodium hydroxide solution to obtain a first-stage monomer solution. In addition, 291.25 g (87.29 mol%) of a 50% aqueous acrylamide solution, 4.43 g (1.2 mol%) of dimethylaminoethyl methacrylate, 76% methacryloxyl dimethyl benzyl Ammonium chloride aqueous solution (24.54 g, 2.8 mol%) and 1% N, N methylenebisacrylamide (7.24 g, 0.02 mol%) were charged, and the pH was adjusted to 4.5 with 30% sulfuric acid. And a second monomer solution. In a 1 liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 446.85 g of water, 5.55 g of 1% N, N methylenebisacrylamide (0.02 mol% ), Adjusted to pH 4.5 with 1% sulfuric acid, and heated to 50 ° C under a nitrogen gas atmosphere. Then, the first-stage monomer solution, 61.60 g of a 0.2% aqueous solution of ammonium persulfate and 61.30 g of a 1% aqueous solution of sodium hydrogen sulfite were respectively continuously dropped into the reaction vessel over 14 minutes. During dropping, the internal temperature was kept at 50 ° C. After completion of the dropwise addition, the mixture was maintained at 50 ° C. for 10 minutes, and then the monomer solution (B) was added dropwise over 56 minutes. After completion of the dropwise addition, the polymerization reaction was carried out at 50 ° C for 100 minutes to obtain a polymer solution with a solid content of 20.4%, pH 4.6, and viscosity (25, using a Brookfield rotational viscometer) of 5,76 OmPa · s. Was. Table 6

(Synthesis method where monomer B consists of components (a), (b), (c) and (d))

Example 32 (Synthesis method in which monomer B is composed of components (a), (b), and (c)) One-liter four-neck water equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube g, 50% acrylamide aqueous solution 277.05 g (81.10 mol%), 76% acryloyloxhetyldimethylbenzylammonium chloride aqueous solution 29.85 g (3.5 mol %), 6.25 g (2.0 mol%) of itaconic acid, 29.64 g (0.39 mol%) of a 5% aqueous solution of sodium methallylsulfonate, 2.38 g of NN, -dimethylacrylamide (1. (0 mol%) and 0.5% triacrylformal (11.98 g, 0.01 mol%), and adjusted to pH 3.0 with 30% sodium hydroxide. Then The temperature was raised to 60 ° C in a nitrogen gas atmosphere. 5.48 g of a 5% aqueous solution of ammonium persulfate was added, polymerization was started, and the temperature was raised to 85 ° C. When the conversion of these first-stage monomers (monomers (A)) reaches about 50%, 93.31 g of separately charged water and 34.16 g of a 50% aqueous acrylamide solution (10.0 mol%) , 76% acryloyloxetyldimethylbenzylammonium chloride aqueous solution (12.79 g, 1.5 mol%) and itaconic acid (1.56 g, 0.50 mol%) were added dropwise over 20 minutes. It was kept at 80 ° C for 20 minutes. Further, 9.06 g of a 5% aqueous solution of ammonium persulfate was added, and the mixture was kept at 80 ° C as it was. When the estimated viscosity at 25 ° C reached 6,000 to 9,000 mPa's, the reaction was stopped by cooling. A solid solution having a solid content of 20.5%, a pH of 3.7, and a viscosity (using a Brookfield rotational viscometer at 25 ° C) of 6,05 OmPa · s was obtained. Examples 33 to 34 (Synthesis method in which monomer B is composed of components (a), (b), and (c))

Example 32 was carried out in the same manner as in Example 32 except that the conversion of the monomer (A) at the time of dropping the monomer (B) was changed. Table 7 shows the conversion of the monomers (A) at the time of dropping and the properties of the obtained polyacrylamide copolymer. Comparative Example 11-; L 2

Example 32 was carried out in the same manner as in Example 32 except that the conversion of the monomer (A) at the time of dropping the monomer (B) was changed. Table 7 shows the compatibility of the monomers (A) at the time of dropping and the properties of the obtained polyacrylamide-based copolymer.

Table 7

(Synthesis method where monomer B is also a component of (a), (b) and (c))

Example 35 (Synthesis method containing urea)

In a 1-liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 439.66 g of water, 10.00 g of urea, 50% aqueous acrylamide solution as monomers (A) 239. 39 g (56.275 mol%), dimethylaminoethyl methacrylate 5.65 g (1.2 mol%), itaconic acid 7.79 g

(2.0 mol%), 47.32 g (0.50 mol%) of a 5% aqueous solution of sodium methallylsulfonate, and 11.53 g (0-025 mol%) of 1% N, N methylenebisacrylamide The pH was adjusted to 2.5 with 30% sulfuric acid. Then, the temperature was raised to 60 ° C. in a nitrogen gas atmosphere. 6.82 g of a 5% aqueous solution of ammonium persulfate was added, polymerization was started, and the temperature was raised to 85 ° C. When the conversion of these first-stage monomers (Monomers (A)) reached 89.2%, 33.46 g of water, 155.68 g (36.60 mol%) of 50% aqueous acrylamide solution, and 76% Aqueous solution of methacryloyloxyshethyl dimethylbenzylammonium chloride 3 1.29 g (2.8 mol%), itaconic acid 1.95 g (0.50 mol%), and 5% aqueous solution of sodium methallyl sulfonate 9. The mixture was cooled to 80 ° C while adding a monomer aqueous solution consisting of 46 g (0.10 mol%), and kept at 80 ° C. When the estimated viscosity at 25 ° C reaches 6,000 to 9,000 mPas, cool the reaction Stopped. A polymer solution having a solid content of 25.2%, pH 4.1, and viscosity (25 ° C, using a Brookfield rotational viscometer) of 8,82 OmPas was obtained. Comparative Example 13 (Synthesis method containing urea)

In a 1 liter four-necked flask equipped with a stirrer, thermometer, reflux condenser, and nitrogen gas inlet tube, 473.12 water, urea 10, 505.07 g (92.875 mol%) of 50% aqueous acrylamide solution, dimethylamino Ethyl methacrylate 5.6 aqueous ammonium chloride solution 31.29 g (2.8 mol%), itaconic acid 9.74 g (2.5 mol%), 5% sodium methallylsulfonate aqueous solution 56.78 g (0.60 mol%) and 1 1.53 g (0.025 mol%) of 1% N, N methylene bisacrylamide were adjusted to pH 2.5 with 30% sulfuric acid. Otherwise, the synthesis reaction was carried out in the same manner as in Comparative Example 1, and a polymer solution having a solid content of 25.5%, pH 4.2, and viscosity (25 ° C, using a Brookfield rotational viscometer) of 8, 11 OmPa · s was used. Obtained.

(Paper preparation and physical property measurement)

Application example 1

Sulfuric acid band was added to pulp slurry with a concentration of 2.4% adjusted to Canadian Standard Freeness (CSF) 411 and electric conductivity of 1500 ^ SZcm by beaten cardboard waste paper, and 1.0% of pulp solid content was added. Thereafter, the polyacrylamide-based copolymer produced in Example 1 was added at 0.5% based on the pulp solid content, and the mixture was further stirred for 1 minute. After the stirring, the pulp slurry was diluted to 0.8% with water having an electric conductivity of 3000 zS / cm, and then made into paper using a Noble Andud sheet machine to obtain wet paper. The wet paper was pressed and dried with a drum dryer to obtain 80 g / m ² handmade paper. After the obtained handmade paper was conditioned for 24 hours under the conditions of 20 ° C and 65% RH, various measurements were performed. Table 8 shows the measurement results. Physical properties were measured according to the following methods. Specific burst strength '''Based on JISP-8112.

Internal bond strength ··· JAPAN- TAPP I Paper pulp test method No. 54

Breaking length · · Ι Ι Ι 3 Ρ—Compliant with 8113.

DDT · * Using a device similar to that for “Dynamic Drainage Jar” described on page 46 of Tappi, Vol. 56, No. 10, (1973). Pour the diluted pulp slurry (concentration 0.8%) into a jar with a diameter of 7.5 cm, open the lower cock while stirring at 600 rpm, filter through a 100 mesh wire mesh, It measures the time required to reach the filtrate volume and can be used to evaluate drainage

. The time until the filtrate reached 250 g was measured. A smaller value indicates better drainage. Application Examples 2 to 6, Comparative Application Example 1

The same operations as in Application Example 1 were performed, except that in Example 1, the polyacrylamide-based copolymers produced in Examples 2 to 6 and Comparative Example 1 were used. Table 8 shows the measurement results. Comparative application example 2

The same operation as in Application Example 1 was performed, except that the polyacrylamide-based copolymer was not used in Application Example 1. Table 8 shows the measurement results.

Table 8

Application examples 7 to 8, Comparative application example 3

In the application example 1, the polyacrylamide copolymer prepared in the examples 7 to 8 and the comparative example 2 was added to the CSF 360 obtained by beating a dumpling waste paper, the slurry obtained in the examples 7 to 8 and the comparative example 2 to a conductivity of 1 500 liS / cm. The same operation as in Application Example 1 was performed except that 6% was used. Table 9 shows the measurement results. Table 9 Polyacrylamide specific burst strength DDT

Copolymer (seconds)

Application. Recitation 7 2.76 42.0

Application Example 8 2.82 43.5

Comparative application 3 Comparative example 2 2.40 45.8 Application 9

The polyacrylamide copolymer produced in Example 9 is pulp-pulled with 2.4% pulp slurry prepared by beating a corrugated pole waste paper and adjusting to Canadian Standard Freeness (CSF) 363, conductivity 1500 SZcm. A solid content of 0.15% was added, and the mixture was further stirred for 1 minute. After stirring, the pulp slurry was diluted to 0.8% with water having a pH of 7.5 and an electric conductivity of 1000 S / cm, and 0.03% of a retention agent Himoloc NR-12MLS (manufactured by Himo Co., Ltd.) was added. Paper was made with a Noble & Wood sheet machine to obtain wet paper. The wet paper was pressed and dried with a drum dryer to obtain a hand-made paper of 80 g / m ² . After the obtained handmade paper was conditioned for 24 hours at 20 ° C and 65% RH, various measurements were performed. Table 10 shows the measurement results. Application Examples 10-11, Comparative Application Example 4

The same operation as in Application Example 9 was performed, except that in Example 9, the polyacrylamide-based copolymer produced in Examples 10 to 11 and Comparative Example 3 was used. Table 10 shows the measurement results. Table 10

Application Examples 12 to 20, Comparative Application Example 5

Beating old corrugated paper, Canadian Standard Freeness (CSF) 3 A sulfuric acid band was added at 3.0% to the pulp solid content to a 2.4% pulp slurry adjusted to 80, conductivity 150 S / C HK pH 7.1. Thereafter, the polyacrylamide-based copolymers produced in Examples 12 to 20 and Comparative Example 4 were added in an amount of 0.45% based on the solid content of the pulp, and further stirred for 1 minute. After stirring, the pulp slurry was diluted to 0.8% with water having an electric conductivity of 500 S / cm and pH 6.0, and then made into paper using a Noble and Wood sheet machine to obtain wet paper. Was. The wet paper was pressed and dried with a drum dryer to obtain a hand-made paper of 80 g / m ² . The obtained handmade paper was conditioned for 24 hours at 20 ° C. and 65% RH, and then the specific burst strength was measured. Table 11 shows the measurement results together with the DDT results. table 1

Application Examples 2 1 to 23, Comparative Application Example 6

BKP (L / N = 8/2) adjusted to Canadian Standard Freeness (CSF) 402 2.4% pulp slurry Calcium carbonate (Tamapearl 121S: Okutama Kogyo Co., Ltd.) 10%, Examples 21-23, 0.8% of polyacrylamide copolymer produced in Comparative Example 5 and 2.0% of band sulfate were stirred. Below, it was added sequentially at one minute intervals. Pulp slurry was diluted to 0.8% with water of pH 7 and 0.015% of the retention agent HiMoloc NR-12MLS (manufactured by Himo Co., Ltd.) was added, followed by papermaking using a Noble and Wood sheet machine. Then, a wet paper was obtained. The wet paper was pressed and dried with a drum dryer to obtain a hand-made paper of 60 g / m. After the obtained handmade paper was conditioned for 24 hours at 20 ° C and 65% RH, the specific burst strength, internal bond strength, and breaking length were measured. Table 12 shows the obtained results. Comparative application example 7

The same operations as in Application Example 21 were performed except that the polyacrylamide-based copolymer was not used in Application Example 21. Table 12 shows the measurement results. Table 12

Application examples 24 to 31, Comparative application examples 8 to 12

Recovered corrugated paper and beaten Canadian Standard Freeness (CSF) 378, conductivity adjusted to 1500 SZ cm with calcium sulfate 2.4% pulp slurry, sulfuric acid band 1. 0% was added. Thereafter, the polyacrylamide-based copolymers produced in Examples 24 to 31 and Comparative Examples 6 to 10 were added in an amount of 0.4% based on the solid content of pulp, and the mixture was further stirred for 1 minute. After stirring, the pulp slurry was diluted to 0.8% with water adjusted to an electric conductivity of 1500 zS / cm with calcium sulfate at pH 5, and then made into a paper with a Noble & Wood sheet machine to obtain a wet paper. Was. The wet paper was pressed and dried with a drum dryer to obtain 80 g / m ² handmade paper. After the obtained handmade paper was conditioned for 24 hours at 23 ° C and 50% RH, the internal bond strength was measured. Table 13 shows the measurement results together with the DDT results. Comparative application example 13

The same operations as in Application Example 24 were performed, except that the polyacrylamide-based copolymer was not used in Application Example 24. Table 13 shows the measurement results. Table 13

Polyacrylamide internal bond strength DDT

Copolymer (mJ) (sec)

Application Example 24 Example 24 285 51.3

Application 25 Example 25 292 50.0

Application Example 26 Example 26 2S5 49.5

Application Example 27 Example 27 295 49.0

Application Example 28 Example 28 308 48.6

Application Row 29 Example 29 290 45.8

Application 30 Implementation ί Row 30, 313 49.2

Application 31 Example 3Ί 306 47.2

Comparative application ί Row 8 Comparative example 6 260 60.2

Comparative application example 3 Comparative 1 'row 7 283 57.4

Comparative application ί Row 10 Comparative example 8 265 69.0

Comparative application example 11 Comparative 1 3 262 66.7

Comparative application 1 'row 12 Comparative example 10 267 63.9

Comparative application ί Row 13 190 150 Application Examples 32-34, Comparative Application Examples 14-: L5

In Application Example 1, the polyacrylamide copolymers produced in Examples 32 to 34 and Comparative Examples 1 to 12 were added in an amount of 0.4% based on the solid content of pulp, and 2.0% of a sulfate band was added. Except for, the same operation as in application example 1 was performed. Table 14 shows the measurement results of the specific burst strength. Comparative application example 16

In Application Example 32, the same operation as in Application Example 32 was performed, except that the polyacrylamide-based copolymer was not used. Table 14 shows the measurement results. Table 14

Application 35, Comparative application 17

To the deinked pulp (DIP), a sulfuric acid band was added at 3.0% based on the pulp solid content, followed by stirring for 1 minute. Thereafter, the polyacrylamide-based copolymers produced in Example 35 and Comparative Example 13 were added in an amount of 0.2% based on the pulp solid content, and further stirred for 1 minute.

The pulp slurry was diluted to 0.8% with water adjusted to an electric conductivity of 2000 SZcm with pH 4.5 and calcium sulfate, and then made into paper using a Noble and Wood sheet machine to obtain wet paper. After pressing the wet paper, dry it with a drum dryer To obtain a 4 3 g Roh m ² of hand-made paper Te. After the obtained handmade paper was conditioned for 24 hours at 23 ° C and 50% RH, the internal bond strength and the breaking length were measured. Table 15 shows the measurement results. Comparative application example 1 8

In Application Example 35, the same operation as in Application Example 35 was performed except that the polyacrylamide-based copolymer was not used. Table 15 shows the measurement results.

Table 15

Industrial applicability

As shown in Tables 7 to 15, the papermaking additives manufactured according to the present invention were compared with polyacrylamide copolymers manufactured by a conventionally known manufacturing method.

The effect of enhancing paper strength and drainage can be provided.

Claims

The scope of the claims

1. (a) (meth) acrylamide, (b) vinyl monomer having carboxylic acid group and Z or sulfonic acid group and salts thereof, (c) vinyl monomer having tertiary amino group or quaternary ammonium salt, and ( d) After the polymerization initiator is added to the monomer (A) containing the crosslinkable monomer and polymerization is started, when the reaction rate of the monomer (A) reaches 20 to 96.5%, (A) (meth) acrylamide,

(b) a vinyl monomer having a carboxyl group and a Z or sulfonic acid group and salts thereof; (c) a vinyl monomer having a tertiary amino group or a quaternary ammonium salt; and (d) at least one monomer of a crosslinking monomer. A class of monomers containing

A method for producing a papermaking additive, comprising polymerizing (B) dropwise.

2. The papermaking additive according to claim 1, wherein the monomer (B) to be dropped in claim 1 comprises (b) a vinyl monomer having a hydroxyl group and / or a sulfonic acid group and a salt thereof. Method of manufacturing the agent.

3. The papermaking additive according to claim 1, wherein the monomer (B) to be dropped in claim 1 comprises (c) a vinyl monomer having a tertiary amino group or a quaternary ammonium salt. Production method.

4. The monomer (B) to be dropped in claim 1 is (b) a bimer monomer having a carboxyl group and Z or a sulfonic acid group and a salt thereof, and (c) a tertiary amino group or a quaternary ammonium salt. The method for producing a papermaking additive according to claim 1, wherein the method comprises a bimer monomer having the same.

5. The monomer (B) to be dropped in claim 1 is (a) (meth) acrylamide, (b) a pinyl monomer having a carboxyl group and / or a sulfonic acid group and salts thereof, (c) a tertiary amino group, Or a vinyl monomer having a quaternary ammonium salt, and (d) a crosslinkable monomer. A method for producing a papermaking additive.

6. The method according to any one of claims 1 to 5, wherein the monomer (B) is dropped and polymerized when the reaction rate of the monomer (A) reaches 30 to 90%. The method for producing a papermaking additive according to claim 1.

7. The method for producing a papermaking additive according to any one of claims 1 to 6, wherein the polymerization is carried out in the presence of a urea compound.

8. A papermaking additive comprising the copolymer produced by the method for producing a papermaking additive according to any one of claims 1 to 7.

9. A paper containing the papermaking additive according to claim 8.