JP2007023146A - Ionic fine particle and application of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide ionic fine particles having characteristics of both of water-insoluble ionic particles and a water-soluble crosslinked polymer, invisible by an ordinary optical microscope and visible by a phase contrast microscope and having ionic character of cationic or amphoteric character, and to provide application of the same. <P>SOLUTION: The ionic fine particles are prepared by polymerizing a water-soluble vinyl monomer in a condition in which the monomer concentration is set at 15-60% by mass in initiation of the polymerization. The ionic fine particles manifests excellent performance in sludge dehydrating agents, yield enhancers and water filtering property-improving agents. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to ionic fine particles and uses thereof, and more specifically, cationic or amphoteric ionicity comprising a radical (co) polymer obtained by polymerizing a water-soluble vinyl monomer at a monomer concentration of 15 to 60% by mass at the start. The present invention relates to an ionic fine particle characterized by being able to be confirmed for the first time with a phase-contrast microscope, which cannot be confirmed with a normal microscope, and its use.

Conventionally, ionic water-soluble polymers have been used as a polymer flocculant for various applications. However, many water-insoluble and water-swellable ionic polymer fine particles have been developed and used with many problems aiming at further functions.

These water-insoluble and water-swellable ionic polymer fine particles are produced by water-in-oil reverse-phase emulsion polymerization in the presence of a crosslinkable monomer, and can usually be observed with an optical microscope, and their particle size is easy. Has been measured.

On the other hand, a method of using an ionic vinyl polymer having a water-soluble cross-linked structure using a cross-linkable monomer as a sludge dehydrating agent has been shown, but it is naturally observed with a normal optical microscope because it is water-soluble. I can't do it. It is water soluble and different from the particles of the present invention.

As described above, it is known that water insolubility and a water-soluble crosslinked structure are characteristic and effective in various applications of the polymer flocculant. However, ionic fine particles having both characteristics of being water-insoluble and water-soluble and having a crosslinked structure have not yet been disclosed.

Patent No. 2135284 Japanese Patent No. 2575692 Patent No. 321857 JP-A 64-085199 JP 2000-024700 A

The problem to be solved by the present invention is to provide an ionic fine particle characterized by having a cationic property or an amphoteric property and its use, which is a fine particle that cannot be confirmed with a normal optical microscope but can be confirmed with a phase contrast microscope. That is.

As a result of detailed studies to solve the above-mentioned problems, by proceeding the reaction under specific polymerization conditions, particles that cannot be confirmed with a normal optical microscope but can be confirmed for the first time with a phase contrast microscope, It has been found that the fine particles can be produced. Furthermore, it has been discovered that the ionic fine particles exhibit excellent performance in the aggregating action of suspended solids.

That is, the invention of claim 1 is a cationic or amphoteric ionic fine particle comprising a radical (co) polymer obtained by polymerizing a water-soluble vinyl monomer at a starting monomer concentration of 15 to 60% by mass, It is an ionic fine particle characterized by being a particle that cannot be confirmed with an optical microscope and can only be confirmed with a phase contrast microscope.

一般式（１）
Ｒ１は水素又はメチル基、Ｒ２〜Ｒ４はベンジル基あるいは炭素数１〜３のアルキル基であり同種でも異種でも良い、Ａは酸素又はＮＨ、Ｂは炭素数２〜４のアルキレン基又はアルコキシレン基、Ｘ１は陰イオンをそれぞれ表わす。

一般式（２）
Ｒ５は水素、メチル基又はカルボキシメチル基、ＡはＳＯ３、Ｃ６Ｈ４ＳＯ３、ＣＯＮＨＣ（ＣＨ３）２ＣＨ２ＳＯ３、Ｃ６Ｈ４ＣＯＯあるいはＣＯＯ、Ｒ６は水素又はＣＯＯＹ２、Ｙ１あるいはＹ２は水素又は陽イオンをそれぞれ表わす。 The invention of claim 2 is characterized in that the ionic particles have a structure of a cationic water-soluble vinyl monomer represented by the following general formula (1) or an anionic water-soluble vinyl monomer represented by the following general formula (2) as appropriate. The ionic microparticle according to claim 1, wherein the ionic microparticle is a radical copolymer contained in a unit.

General formula (1)
R1 is hydrogen or methyl group, R2 to R4 are benzyl group or alkyl group having 1 to 3 carbon atoms, which may be the same or different, A is oxygen or NH, B is alkylene group or alkoxylene group having 2 to 4 carbon atoms , X1 each represents an anion.

General formula (2)
R5 represents hydrogen, methyl group or carboxymethyl group, A represents SO3, C6H4SO3, CONHC (CH3) 2CH2SO3, C6H4COO or COO, R6 represents hydrogen or COOY2, Y1 or Y2 represents hydrogen or a cation, respectively.

According to a third aspect of the present invention, the ionic fine particles include a cationic water-soluble vinyl monomer represented by the general formula (1) or an anionic water-soluble vinyl monomer represented by the general formula (3) as appropriate. The ionic fine particles according to claim 1 or 2, wherein the monomer mixture aqueous solution is produced by a dispersion polymerization method in which a soluble polymer dispersant coexists in the salt aqueous solution in the salt aqueous solution.

The invention of claim 4 is characterized in that the particle size of the ionic fine particles is in the range of 800 nm to 100 μm in a 4% by mass sodium chloride aqueous solution. It is.

The invention of claim 5 is a sludge dewatering agent comprising the ionic fine particles according to any one of claims 1 to 4.

The invention of claim 6 is a yield improver comprising the ionic fine particles according to any one of claims 1 to 4.

A seventh aspect of the present invention is a drainage improver comprising the ionic fine particles according to any one of the first to fourth aspects.

The cationic or amphoteric fine particles (hereinafter referred to as ionic fine particles) of the present invention are fine particles having the characteristics of a water-insoluble ionic fine particle and a water-soluble ionic polymer having a crosslinked structure. The generation of the fine particles is estimated as follows. That is, it is considered that by performing a polymerization reaction at a high concentration, a part of the produced polymer is entangled or crystallized, or particles are produced by a combined action thereof. In dispersion polymerization in an aqueous salt solution, the polymerized polymer undergoes a process of shrinking and precipitating. However, since the density of the polymer in the precipitation system is significantly higher than that in the aqueous solution, ionic particles can be produced even at relatively low concentrations. It is thought to generate. Since it is a fine particle having the characteristics of a water-insoluble ionic fine particle and a water-soluble ionic polymer having a crosslinked structure, the following usage can be expected. That is, there are a wide variety of uses as a polymer flocculant, in particular, a wastewater treatment agent, a sludge dehydrating agent, a yield improving agent, and a drainage improving agent. Therefore, it greatly contributes to the industry.

The present invention will be specifically described below. The ionic fine particles of the present invention are fine particles that cannot be confirmed with a normal optical microscope but can be confirmed for the first time with a phase contrast microscope, and are characterized in that they are cationic or amphoteric. Water-soluble cationic or amphoteric crosslinked polymers have improved suspension agglomeration performance, such as floc-forming performance, compared to uncrosslinked cationic or amphoteric polymers, but there is a tendency for the optimum addition amount to increase slightly. On the other hand, water-insoluble cationic or amphoteric fine particles form strong flocs and are stable against shearing force, but have a feature that the optimum addition amount tends to increase. The ionic fine particles of the present invention are characterized by having the above-mentioned performance.

The details of the reaction that the ionic microparticles produce are still unknown, but are estimated as follows. That is, it is considered that by performing a polymerization reaction at a high concentration, a part of the produced polymer is entangled or crystallized, or particles are produced by a combined action thereof. In dispersion polymerization in an aqueous salt solution, the polymerized polymer undergoes a process of shrinking and precipitating. However, since the density of the polymer in the precipitation system is significantly higher than that in the aqueous solution, ionic particles can be produced even at relatively low concentrations. It is thought to generate. That is, the concentration of the water-soluble vinyl monomer at the start of polymerization is in the range of 15 to 60% by weight with respect to the monomer dissolved phase. In particular, in the polymerization method in the presence of a polymer dispersant that is soluble in the aqueous salt solution in the aqueous salt solution, the content is preferably in the range of 15 to 40% by weight.

The ionic fine particles of the present invention can be produced by polymerization of a water-soluble vinyl monomer. The polymerization method is not particularly limited, but in consideration of the properties of the polymer, reaction control, etc., a water-in-oil reverse phase emulsion polymerization method or a dispersion polymerization method in the presence of a water-soluble polymer dispersant in a salt solution is preferable. A dispersion polymerization method in an aqueous salt solution in which the density of the polymer produced through a phase separation process during the polymerization is high is more preferable.

The water-in-oil inverse emulsion polymerization method is effective for forming a water-in-oil emulsion, an oily substance composed of water-soluble vinyl monomer mixture and a crosslinking component as water, an oily substance composed of at least water-immiscible hydrocarbon as a dispersion medium. It can be synthesized by mixing at least one surfactant having an amount and HLB, followed by vigorous stirring to form a water-in-oil emulsion, followed by polymerization.

In dispersion polymerization in an aqueous salt solution, a water-soluble vinyl monomer mixture is mixed with water, a salt, a polymer dispersant that is soluble in an aqueous salt solution, and in some cases, a crosslinking component, and the polymer is precipitated while being polymerized and dispersed in the aqueous solution. Can be synthesized.

As the water-soluble vinyl monomer, a cationic water-soluble vinyl monomer alone or a nonionic water-soluble vinyl monomer, or an anionic vinyl monomer is used. Examples of the cationic water-soluble vinyl monomer include tertiary amyl group-containing monomers such as dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylamide, and methyldiallylamine, and salts thereof. Further, (meth) acryloyloxyethyltrimethylammonium chloride, (meth) acryloyloxyethyldimethylethylammonium chloride (meth) acryloylaminopropyltrimethyl, which is a quaternized product of the above tertiary amino group-containing monomer with methyl chloride or the like. Ammonium chloride, (meth) acryloyloxyethyldimethylbenzylammonium chloride, (meth) acryloyloxy 2-hydroxypropyldimethylbenzylammonium chloride, (meth) acryloylaminopropyldimethylbenzylammonium chloride, dimethyldiallylammonium chloride, etc. It is possible to use one type or two or more types together.

Examples of nonionic water-soluble vinyl monomers include (meth) acrylamide, N, N-dimethylacrylamide, acrylonitrile, 2-hydroxyethyl (meth) acrylate, diacetone acrylamide, N-vinylpyrrolidone, N-vinylformamide, N-vinylacetamide and the like can be raised, and one or more of these can be used in combination.

Examples of anionic water-soluble vinyl monomers include vinyl sulfonic acid, vinyl benzene sulfonic acid, 2-acrylamido 2-methylpropane sulfonic acid, (meth) acrylic acid, itaconic acid, maleic acid, p-carboxystyrene, and the like. . One or more of these can be used in combination.

The composition of the monomer to be polymerized (mixture) is 5 to 100 mol% of the monomer represented by the general formula (1) and / or (2), and the monomer 0 to 0 represented by the general formula (3). Monomers (mixtures) comprising 50 mol%, (meth) acrylamide and 0 to 95 mol% of other copolymerizable nonionic water-soluble monomers are preferred. Further preferable monomer (mixture) composition is 5 to 50 mol% of the monomer represented by the general formula (1) and / or (2), and the monomer 0 to 0 represented by the general formula (3). 30 mol%, (meth) acrylamide and 50 to 95 mol% of other nonionic water-soluble monomers copolymerizable. Further preferred monomers are methacryloyloxyethyltrimethylammonium chloride or acryloyloxyethyltrimethylammonium chloride, and the most preferred monomer combinations are methacryloyloxyethyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride. Each combination of chloride and acrylamide, or methacryloyloxyethyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride, acrylic acid and acrylamide.

Salts used in the dispersion polymerization method in the presence of a water-soluble polymer dispersant in an aqueous salt solution include cations such as alkali metal ions and ammonium ions such as sodium and potassium, halides, sulfate ions, nitrate ions, and phosphoric acid. Salts in combination with anions such as ions, acetate ions and citrate ions are raised. These salts can be used alone or in combination, and the concentration ranges from 10% by weight to the saturated concentration.

As the polymer dispersing agent to be coexisted, either ionic or nonionic can be used, but ionic is preferable, and cationic is more preferable. As the cationic polymer dispersant, a (co) polymer of a cationic monomer such as (meth) acryloyloxyethyltrimethylammonium chloride or dimethyldiallylammonium chloride is used, but the cationic monomer and the nonionic monomer are used. These copolymers can also be used. Examples of nonionic monomers include acrylamide, N-vinylformamide, N-vinylacetamide, N-vinylpyrrolidone, N, N-dimethylacrylamide, acrylonitrile, diacetone acrylamide, 2-hydroxyethyl (meth) acrylate, etc. It is done.

The water-soluble polymer dispersant has a molecular weight of 1,000 to 2,000,000, preferably in the range of 5,000 to 1,000,000. The addition amount of the water-soluble polymer dispersant is in the range of 1 to 20% by weight with respect to the weight of the monomer, and preferably in the range of 2 to 15% by weight in consideration of the dispersion effect and practicality.

In the present invention, in order to produce ionic fine particles, it is not essential that the monomer mixture contains a covalent cross-linking component, but it can be used in combination. At this time, the presence of the crosslinking component promotes the formation of the particles and the stabilization of the presence.

There is no particular limitation on the covalently crosslinking component, and it is also possible to copolymerize a polyfunctional vinyl monomer having a plurality of vinyl groups with a monomer mixture, or an active group in a polymer obtained by copolymerizing the monomer mixture. It is also possible to crosslink after polymerization with a crosslinking component having a plurality of reactive functional groups. Furthermore, although crosslinking by radiation, plasma, oxidizing agent, etc. is possible, it is preferable to copolymerize with a polyfunctional vinyl monomer in view of ease of production, cost and the like. Examples of polyfunctional vinyl monomers include N, N′-methylenebis (meth) acrylamide, triallylamine, ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and 1,3-butylene glycol di (meth) acrylate. N-vinyl (meth) acrylamide and the like.

An appropriate addition amount of the covalent crosslinking component needs to be appropriately determined in consideration of the efficiency of the crosslinking agent, the molecular weight, the reaction conditions, etc., but generally 0.5 to It is in the range of 50,000 ppm. A chain transfer agent such as isopropyl alcohol or sodium methallyl sulfonate can also be used in the range of 1 to 50,000 ppm based on the weight of the monomer mixture.

Examples of oily substances consisting of hydrocarbons used as dispersion media when polymerized by water-in-oil emulsion polymerization include paraffins, mineral oils such as kerosene, light oil, and middle oil, or boiling points in substantially the same range as these. And hydrocarbon-based synthetic oils having characteristics such as viscosity and mixtures thereof. As content, it is the range of 20 mass%-50 mass% with respect to the water-in-oil type emulsion whole quantity, Preferably it is the range of 20 mass%-35 mass%.

Examples of at least one surfactant having an amount effective to form a water-in-oil emulsion and HLB are HLB 3-11 nonionic surfactants, specific examples of which include sorbitan monooleate Sorbitan monostearate, sorbitan monopalmitate and the like. The addition amount of these surfactants is 0.5 to 10% by weight, preferably 1 to 5% by weight, based on the total amount of the water-in-oil emulsion.

After the polymerization of the water-in-oil emulsion, a hydrophilic interfacial modifier called a phase inversion agent is added to make the emulsion particles covered with the oil film easy to become familiar with water, and the water-soluble polymer inside is easily dissolved. Treat, dilute with water and use for each application. Examples of hydrophilic interfacial chemicals are cationic interfacial chemicals and nonionic interfacial chemicals of HLB 9-15, such as polyoxyethylene polyoxypropylene alkyl ether systems and polyoxyethylene alcohol ether systems. is there.

The polymerization reaction can be performed by radical (co) polymerization of the monomer mixture in the presence of a polymerization initiator. The polymerization initiator is not particularly limited as long as it is a general radical polymerization initiator, and azo, peroxide, redox polymerization initiators, photopolymerization initiators, and the like can be used. Examples of system initiators are 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexanecarbonitrile), 2,2′-azobis (2-methylbutyronitrile), 2,2 '-Azobis (2-methylpropionate), 4,4-azobis (4-methoxy-2,4dimethyl) valeronitrile, and the like. Examples of water-soluble azo initiators include 2,2'-azobis. (Amidinopropane) dihydrochloride, 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride, 4,4′-azobis (4-cyanovaleric acid )etc It is below.

Examples of redox systems include a combination of ammonium peroxodisulfate and sodium sulfite, sodium hydrogen sulfite, trimethylamine, tetramethylethylenediamine, and the like. Further examples of peroxides include ammonium or potassium peroxodisulfate, hydrogen peroxide, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, succinic peroxide, t-butylperoxy 2-ethylhexanoate, and the like. I can give you. Examples of the photopolymerization initiator include benzoin ethyl ester and benzoin isopropyl ester. The addition amount of these polymerization initiators varies depending on the purpose of the product and the reaction temperature, but is in the range of 10 to 10,000 ppm with respect to the monomer weight, and can be added all at once or in multiple portions. It is also possible.

The temperature of the polymerization reaction varies depending on the selected initiator and the purpose of the cation particles, but is generally in the range of 5 to 100 ° C. In consideration of the efficiency of the polymerization initiator and the control of the reaction rate, When applying the water-type emulsion polymerization method, it is in the range of 20 to 80 ° C., preferably in the range of 20 to 60 ° C., and in the polymerization reaction in the presence of the water-soluble polymer dispersant in the aqueous salt solution, it is in the range of 20 to 60 ° C. preferable.

The ionic fine particles of the present invention thus produced have a particle diameter in the range of 800 nm to 100 μm in a 4% by mass aqueous sodium chloride solution. Particles smaller than 800 nm are unrealistic with manufacturing difficulties, and particles larger than 100 μm do not exhibit characteristic performance.

When ionic fine particles in such a state are used as a sludge dewatering agent, strong flocs are formed with a small addition amount compared to water-insoluble ionic fine particles and water-soluble ionic polymers having a crosslinked structure. Furthermore, there is a merit that the dehydrated cake is less sticky and the moisture content is lowered. Further, it can be used in combination with one or more selected from inorganic flocculants, cationic / anionic and amphoteric water-soluble polymers.

Similarly, when the ionic fine particles in such a state are used as a yield improver in the paper industry, the paper-making raw material flocs do not become enormous and are tightened to a small size, which is strong in market share. Accordingly, not only the yield is improved, but also paper having a good texture can be produced. Further, it can be used in combination with one or more selected from inorganic flocculants, cationic / anionic and amphoteric water-soluble polymers.

Furthermore, when the ionic fine particles in such a state are used as a drainage improver in the paper industry, in addition to the drainage improvement effect due to the formation of flocs in the papermaking raw material, the moisture content of the flocs is reduced, so drying in the dryer part Improves.

Examples of the inorganic flocculant used in combination include aluminum sulfate, polyaluminum chloride, and polyiron sulfate. Examples of the condensed cationic water-soluble polymer among the cationic polymers include amine / epichlorohydrin condensate. Examples of the anionic water-soluble polymer include homopolymers such as (meth) acrylic acid, itaconic acid, maleic acid, and acrylamide 2-methylpropanesulfonic acid, or copolymers selected from two or more of the above monomers, or ( And copolymers with (meth) acrylamide. An example of the amphoteric water-soluble polymer is a copolymer of a monomer mixture comprising a cationic monomer and an anionic monomer, and optionally a nonionic monomer such as (meth) acrylamide. Examples of cationic water-soluble polymers are polymers of one or more cationic monomers, or copolymers with nonionic monomers such as (meth) acrylamide.

Examples of the cationic monomer include dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylamide, and methyl diallylamine. Examples of the quaternary ammonium group-containing monomer include (meth) acryloyloxyethyltrimethylammonium chloride and (meth) acryloyloxy 2-hydroxy which are quaternized products of the tertiary amino-containing monomer with methyl chloride or benzyl chloride. Propyltrimethylammonium chloride, (meth) acryloylaminopropyltrimethylammonium chloride, (meth) acryloyloxyethyldimethylbenzylammonium chloride, (meth) acryloyloxy 2-hydroxypropyldimethylbenzylammonium chloride, (meth) acryloylaminopropyl Dimethylbenzylammonium chloride, dimethyldiallylammonium chloride and the like.

The molecular weight of the condensed cationic water-soluble polymer or the anionic, cationic or amphoteric water-soluble polymer used in combination is preferably in the following range. In the case of the condensation system, it is several thousand to several hundred thousand, and the anionic, cationic or amphoteric water-soluble polymer is 1,000,000 to 20 million, preferably 5 million to 15 million.

When used in combination with the ionic fine particles of the present invention, the amount of the inorganic flocculant added is in the range of 0.1 to 5%, preferably 0.5 to 3% per papermaking raw material (hereinafter the same). It is a range. The addition amount of the condensed cationic aqueous polymer is in the range of 50 to 2000 ppm, preferably in the range of 50 to 500 ppm. The addition amount of the anionic, cationic or amphoteric water-soluble polymer is in the range of 20 ppm to 5000 ppm, preferably in the range of 50 ppm to 1000 ppm.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples.

A four-necked 500 ml separable flask equipped with a stirrer, reflux condenser, thermometer and nitrogen inlet tube was charged with 205.8 g of deionized water, 148.8 g of ammonium sulfate, and 80 wt% acryloyloxyethyltrimethylammonium chloride as a cationic vinyl monomer. (Hereinafter referred to as DMQ) 18.7 g and 80 wt% methacryloyloxyethyldimethylbenzylammonium chloride (hereinafter DMC) 20.1 g, 50 wt% acrylamide (hereinafter AAM) 87.9 g, acryloyloxyethyltrimethylammonium chloride heavy as a dispersant 18.8 g (20% by weight aqueous solution, 20% by weight aqueous solution viscosity 6450 mPa · s) of each compound (hereinafter pDM) was charged. Thereafter, nitrogen was introduced from the nitrogen introduction tube while stirring to remove dissolved oxygen. During this time, the internal temperature was adjusted to 35 ± 2 ° C. using a constant temperature water bath. 40 minutes after the introduction of nitrogen, 0.75 g of a 1% by weight aqueous solution of 2,2′-azobis [2- (5-methyl-2-imidazolin-2-yl) propane] dihydrochloride as an initiator was added to conduct polymerization. Started. The internal temperature was kept at 35 ± 2 ° C., and 6 hours after the start of polymerization, 0.75 g of the initiator was added, and the reaction was further completed for 10 hours. This obtained dispersion is designated as prototype 1. Table 1 shows the preparation amount of the prototype 1 and Table 3 shows physical properties.

The reaction was carried out in the same manner as in Example 1 except that acrylic acid (hereinafter AAC) was added as an anionic vinyl monomer and the charged weight was changed as shown in Table 1. The obtained dispersion is referred to as prototype 2. Table 1 shows the preparation amount of this prototype, and Table 3 shows the physical properties.

The reaction was performed in the same manner as in Example 1 or 2 except that the charged weight was changed as shown in Table 1. The obtained dispersions are designated as prototypes 3 to 6, and the amounts charged for these prototypes are shown in Table 1, and the physical properties are shown in Table 3.

The reaction was carried out in the same manner as in Example 1 except that methylenebisacrylamide (hereinafter referred to as MBA) was added as a crosslinking component in the amount shown in Table 1. The obtained dispersions are designated as prototype 7 and prototype 8, and the amounts charged in these prototypes are shown in Table 1 and the physical properties are shown in Table 3.

In a reaction vessel equipped with a stirrer and a temperature controller, 15.0 g of sorbitan monooleate (SOL) was charged and dissolved in 140 g of isoparaffin (hereinafter referred to as ISP) having a boiling point of 190 ° C. to 230 ° C. Separately, 46.2 g of DMQ 80% by weight aqueous solution, 49.5 g of DMC 80% by weight aqueous solution 216.9 g of AAM 50% by weight aqueous solution, 1.8 g of MBA 0.1% by weight aqueous solution, and 30.6 g of ion-exchanged water were collected, mixed and completely dissolved. It was. Thereafter, the oil and the aqueous solution were mixed, and stirred and emulsified with a homogenizer at 1000 rpm for 15 minutes. After maintaining the temperature of the monomer solution in the range of 46 to 50 ° C. and performing nitrogen substitution for 30 minutes, 0.7 g of dimethyl-2,2-azobisisobutyrate was added to start the polymerization reaction. It was. The reaction was completed at a reaction temperature of 46 to 50 ° C. for 12 hours to complete the reaction. After polymerization, 5.0 g of polyoxyethylene polyoxypropylene alkyl ether was added to and mixed with the resulting water-in-oil emulsion as a phase inversion agent. This water-in-oil emulsion thus obtained is designated as prototype 9. Table 2 shows the preparation table of this prototype 9, and Table 3 shows the physical properties.

The reaction was performed in the same manner as in Example 9 except that the charged weight was changed as shown in Table 2. The obtained water-in-oil emulsions were designated as prototype 10 and prototype 11, and the amounts charged in these prototypes are shown in Table 2, and the physical properties are shown in Table 3.

(Comparative Synthesis Example 1) The reaction was carried out in the same manner as in Example 1 except that the amount charged was changed as shown in Table 1 and the concentration of the water-soluble monomer was 10% by weight. The obtained dispersions are referred to as comparisons 1 to 6, respectively, and the amounts charged in these comparisons are shown in Table 1, and the physical properties are shown in Table 3.

(Comparative Synthesis Example 2) The reaction was carried out in the same manner as in Examples 5-6 except that MBA was not added as shown in Table 2. The obtained water-in-oil emulsions were set as Comparative Examples 7 to 9, Table 2 shows the preparation amounts for these comparisons, and Table 3 shows the physical properties.

ＤＭＱ：アクリロイルオキシエチルトリメチルアンモニウム塩化物（８０重量％水溶液）
ＤＭＣ：メタクリロイルオキシエチルトリメチルアンモニウム塩化物（８０重量％水溶液）
ＡＡＣ：アクリル酸（６０重量％水溶液）、ＡＡＭ：アクリルアミド（５０重量％水溶液）、ＭＢＡ：Ｎ，Ｎ−メチレンビスアクリルアミド（０．１重量％水溶液）ｐＤＭ：アクリロイルオキシエチルトリメチルアンモニウム塩化物重合体（２０重量％水溶液）、ＡＳＴ：硫酸アンモニウム
数値の単位：質量ｇ Table 1

DMQ: acryloyloxyethyltrimethylammonium chloride (80% by weight aqueous solution)
DMC: Methacryloyloxyethyltrimethylammonium chloride (80% by weight aqueous solution)
AAC: acrylic acid (60 wt% aqueous solution), AAM: acrylamide (50 wt% aqueous solution), MBA: N, N-methylenebisacrylamide (0.1 wt% aqueous solution) pDM: acryloyloxyethyltrimethylammonium chloride polymer ( 20% by weight aqueous solution), AST: ammonium sulfate unit: mass g

ＤＭＱ：アクリロイルオキシエチルトリメチルアンモニウム塩化物（８０重量％水溶液）
ＤＭＣ：メタクリロイルオキシエチルトリメチルアンモニウム塩化物（８０重量％水溶液）、ＡＡＭ：アクリルアミド（５０重量％水溶液）
ＭＢＡ：Ｎ，Ｎ−メチレンビスアクリルアミド（０．１重量％水溶液）
ＩＳＰ：沸点１９０°Ｃないし２３０°Ｃのイソパラフィン
ＳＯＬ：ソルビタンモノオレート
数値の単位、質量：ｇ Table 2

DMQ: acryloyloxyethyltrimethylammonium chloride (80% by weight aqueous solution)
DMC: methacryloyloxyethyltrimethylammonium chloride (80 wt% aqueous solution), AAM: acrylamide (50 wt% aqueous solution)
MBA: N, N-methylenebisacrylamide (0.1 wt% aqueous solution)
ISP: isoparaffin SOL having a boiling point of 190 ° C to 230 ° C: unit of sorbitan monooleate numerical value, mass: g

数値の単位
モノマー濃度：質量％、顕微鏡観察結果：μｍ、カチオン当量値：ｍｅｑ／ｇ、
カチオン当量値はｐＨ１０．０におけるコロイド滴定法での測定による。 Table 3

Numerical unit monomer concentration: mass%, microscopic observation result: μm, cation equivalent value: meq / g,
The cation equivalent value is determined by measurement with a colloid titration method at pH 10.0.

As can be seen from Table 3, in the examples, as a result of observation with a phase contrast microscope, ionic fine particles that could not be confirmed with an optical microscope were observed. In the comparative example, particles were not observed in both the phase contrast microscope and the optical microscope. In particular, as a feature of dispersion polymerization in an aqueous salt solution, ionic fine particles were confirmed regardless of whether or not a crosslinking agent was used.

A sludge dewatering test was conducted using ionic fine particle prototypes 3, 4, 10 and 11 synthesized in Examples 3, 4, 10 and 11. Human waste surplus sludge (pH 6.50, total ss content 20,500 mg / L) was collected in a 200 mL poly beaker, and prototypes 3, 4, 10 and 11 were added as sludge dehydrating agents to the total weight of 150 ppm, and the beaker was transferred and stirred 20 times. After performing, it filtered with the T-1178L nylon filter cloth, and measured the filtrate amount 45 seconds afterward. Moreover, after observing the cake supportability (hardness of the dehydrated cake) of the filtered sludge, it was dehydrated at a press pressure of 2 kg / m ² for 1 minute to confirm the filter cloth peelability, and the moisture content of the cake (105 ° C., dried for 20 hours) Was measured. The results are shown in Table 4.

(Comparative Test 1) Using Comparative Examples 4 to 6 and Comparative Examples 8 and 9, a sludge dewatering test was conducted in the same manner as in Example 7, and the filtrate amount, cake supportability, filter cloth peelability, and cake moisture content were measured after 45 seconds. did. The results are shown in Table 4.

４５秒後濾液量単位：ｍＬ、ケーキ支持性、濾布剥離性、良：○、やや不良：△、不良：×、ケーキ含水率：重量％ Table 4

After 45 seconds, filtrate unit: mL, cake support, filter cloth peelability, good: ○, slightly bad: Δ, bad: ×, cake moisture content: wt%

As is apparent from Table 4, the prototypes 3, 4, 10 and 11 of the present invention have a filtered water amount, cake supportability, filter cloth peelability and cake moisture content in comparisons 4 to 6, and prototypes 10 and 11. The amount of drainage is increased, the cake supportability and the filter cloth peelability are good, the cake moisture content is reduced, and the effect is excellent.

Papermaking raw materials mainly composed of LBKP, pH 6.34, total ss content 2.67%, ash content 0.47% as samples, pulp concentration was diluted to 0.5% by weight with tap water, Yield rate was measured. Additives include: cationic starch to papermaking raw material 0.5% by weight, light calcium carbonate to papermaking raw material 20% by weight, neutral rosin size to papermaking raw material 0.5% by weight, sulfuric acid band 0.5% by weight, yield Prototypes 1, 2 and 5-9 of the present invention as improvers are 0.01% by weight of raw materials for papermaking, and anionic polyacrylimide (weight average molecular weight 12.4 million) having an anionic degree of 25 mol% as an anionic polymer 0.01% by weight of the raw material was added to the papermaking raw material, which was put into a bullet type dynamic jar tester in this order and stirred, at intervals of 15 seconds. White water was drained for 10 seconds after 30 seconds to 40 seconds, and the white water was collected for 30 seconds thereafter, and the total yield rate and the ash yield rate were measured. The stirring condition of the Brit type dynamic jar tester is 1000 rpm, wire 125P screen, white water is ADVANTEC No. It filtered with 2 filter paper, and dried at 105 degreeC, and the total yield was measured. The dried filter paper was incinerated at 525 ° C. for 2 hours, and the ash yield was measured. The results are shown in Table 5.

(Comparative Test 2) Using Comparative Examples 1 to 3 and Comparative Example 7, a pulp yield test was conducted in the same manner as in Example 8, and the total yield rate and the ash content yield rate were measured. The results are shown in Table 5.

総歩留率、灰分歩留率の単位：％ Table 5

Unit of total yield rate and ash yield rate:%

As is apparent from Table 5, the trial productions 1 and 2 and the trial productions 5 to 9 of the present invention have a high total yield rate and an ash content yield rate as compared with Comparative Examples 1 to 3 and Comparative Example 7, and a yield improving agent. It can be seen that the effect is excellent.

The cardboard waste paper was disaggregated into a 2% dispersion, and then beaten to 180 mL with a Canadian Standard Freeness (CSF) value. This dispersion was diluted to 0.4% by weight and subjected to a drainage test. The adjusted 0.4 wt% dispersion was collected in a 1000 mL graduated cylinder and used as sulfate band vs. ss 2.0 wt% (pure aluminum oxide) and neutral rosin sizing agent vs. ss 0.1 wt% and freeness improver. Trials 3, 4, 10 and 11 were added to the ss weight of 400 ppm. The graduated cylinder was stirred by inverting it 5 times, put into a CSF tester, and the amount of drainage was measured. After measuring the drainage amount, the pulp remaining on the mesh of the CSF tester was put into a double bottom centrifuge tube having a filter cloth of 100 mesh in the lower part, and dewatered under conditions of 3000 rpm for 5 minutes. . The moisture content of the pulp was measured by measuring the weight of the dehydrated pulp and the dry weight. The results are shown in Table 6.

(Comparative Test 3) Using Comparative Examples 4 to 6 and Comparative Examples 8 and 9, drainage was performed in the same manner as in Example 9, and the amount of filtrate and the moisture content of dehydrated pulp were measured. The results are shown in Table 6.

濾水量：ＣＳＦ値ｍＬ
パルプ含水率：重量％
Table 6

Flow rate: CSF value mL
Pulp moisture content:% by weight

As is apparent from Table 6, the prototypes 3, 4, 10 and 11 of the present invention have a larger drainage amount and a lower pulp moisture content than those of Comparative Examples 4 to 6 and Comparative Examples 8 and 9, and are effective as a drainage improver. It is understood that is superior.

Claims (7)

Cationic or amphoteric ionic fine particles composed of a radical (co) polymer obtained by polymerizing a water-soluble vinyl monomer at a starting monomer concentration of 15 to 60% by mass, which cannot be confirmed with a normal optical microscope Ionic fine particles characterized by being particles that can be confirmed for the first time with a phase contrast microscope. A radical copolymer in which the ionic particles contain a cationic water-soluble vinyl monomer represented by the following general formula (1) or an anionic water-soluble vinyl monomer represented by the following general formula (2) as a structural unit. The ionic microparticle according to claim 1, wherein

General formula (1)
R1 is hydrogen or methyl group, R2 to R4 are benzyl group or alkyl group having 1 to 3 carbon atoms, which may be the same or different, A is oxygen or NH, B is alkylene group or alkoxylene group having 2 to 4 carbon atoms , X1 each represents an anion.

General formula (2)
R5 represents hydrogen, methyl group or carboxymethyl group, A represents SO3, C6H4SO3, CONHC (CH3) 2CH2SO3, C6H4COO or COO, R6 represents hydrogen or COOY2, Y1 or Y2 represents hydrogen or a cation, respectively. A monomer aqueous solution in which the ionic fine particles contain the cationic water-soluble vinyl monomer represented by the general formula (1) or the anionic water-soluble vinyl monomer represented by the general formula (2) as appropriate. The ionic microparticle according to claim 1 or 2, wherein the ionic microparticle is produced by a dispersion polymerization method in which a soluble polymer dispersant coexists in the aqueous salt solution. The ionic fine particles according to any one of claims 1 to 3, wherein the ionic fine particles have a particle size in a range of 800 nm to 100 µm in a 4 mass% sodium chloride aqueous solution. A sludge dewatering agent comprising the ionic fine particles according to any one of claims 1 to 4. A yield improver comprising the ionic fine particles according to any one of claims 1 to 4. A drainage improver comprising the ionic fine particles according to any one of claims 1 to 4.