JP4535826B2 - Powder dispersant and cement dispersant - Google Patents

Description

  The present invention relates to a dispersant for powder comprising a water-soluble lignophenol compound derivative, and a cement dispersant comprising the dispersant.

  Conventionally, lignin has been recovered from pulp effluent, and a method for obtaining a lignin derivative by modifying the lignin has been reported. Lignin sulfonic acid, a kind of such modified lignin, is obtained by treating wood with an aqueous sulfite solution and has been used as a cement dispersant for many years.

  In addition to the above as modified lignin, for example, an alcoholic or phenolic hydroxyl group contained in natural lignin is treated with alkali, dispersed in a solvent, and then reacted with a monohalogenoalkylcarboxylic acid to produce a carboxyalkylated lignin derivative. A method is disclosed (Patent Document 1). According to this method, the alkali treatment increases the polarization of the alcoholic or phenolic hydroxyl group and can enhance the carboxyalkylation. By dispersing in the solvent, the hydrolysis of the monohalogenoalkylcarboxylic acid is suppressed and the lignin in the lignin. The carboxyalkylation reaction of the alcoholic and / or phenolic hydroxyl groups can be sufficiently performed. The derivative is useful as a dispersant for powder because it has a steric hindrance due to the network structure of the molecule inherent to lignin and an adsorption and repulsion effect due to the carboxyl group, thereby suppressing aggregation of hydrophilic powder. The lignin used as a raw material is acetic acid-digested lignin obtained by cooking wood chips at high temperature using acetic acid and hydrochloric acid, and steaming explosion obtained by instantaneously releasing high-pressure saturated steam pressure and crushing wood. Kraft lignin obtained by cooking wood chips at high temperature using lignin or a mixed aqueous solution of sodium hydroxide and sodium sulfide as the cooking liquid.

There are also modified products of acetic acid digested lignin and steamed crushed lignin that are soluble in aqueous solutions in a wide pH range. Specifically, it is a carboxyalkylated product of acetic acid digested lignin and / or steamed crushed lignin, showing water solubility at pH 3 to 13, and absorption of carboxylate anion in the vicinity of 1,750 cm ⁻¹ by measurement of infrared absorption spectrum. It is a carboxyalkylated lignin derivative having increased strength and relatively reduced absorption strength of an alcoholic hydroxyl group near 1,050 cm ⁻¹ (Patent Document 2). The alcoholic or phenolic hydroxyl group of acetic acid-exploded lignin or steamed explosive lignin is carboxylalkylated to obtain a lignin derivative that is excellent in water solubility even in the range of pH 3-13.

On the other hand, there is a method in which lignophenol obtained from plant resources and derivatives thereof are converted into a crosslinked polymer using a water-soluble crosslinking agent and used as a hydrogel having high water absorption properties (Non-patent Document 1). The report was developed as part of the effective utilization of plant resources, and because it is entangled with cellulose three-dimensionally, it is difficult to extract. Therefore, lignin that has been used infrequently is used effectively, and as a product. We propose a resource recycling system that creates new products by converting resources to the molecular level after primary use and before disposal. A hydrogel having excellent water absorption properties is formed by crosslinking the lignophenol obtained in this step. In addition, paying attention to the fact that the plant is constructed as a complex of hydrophilic carbohydrates such as cellulose and hydrophobic lignin, set up another solvent system that does not mix with each other for the constituent carbohydrate and lignin, Lignin is separated by a so-called phase separation system that converts the structure individually in different phases.
JP-A-5-302097 JP-A-6-49223 Research Report of Gifu Life Technology Research Institute No. 2002 5, pp. 26-33, Norio Seki, etc.

  Plants are valuable natural resources, and it is preferable that cellulose and lignin as main components can be easily separated and both can be efficiently used. However, since the methods described in Patent Document 1 and Patent Document 2 are based on lignin previously isolated from plants such as acetic acid digested lignin, there is no description regarding the separation efficiency from cellulose contained in wood chips. .

  Further, in the method described in Non-Patent Document 1, since a so-called phase separation system is adopted, the separation between cellulose and lignin is excellent. However, since the obtained lignophenol derivative is limited to water absorption properties, development of other applications is possible. Is desired.

  The inventors of the present invention have made it possible to allow phenols to act on plant resources to phenolize lignin, thereby facilitating separation of lignin and cellulose, so that the plant resources can be effectively used by a so-called phase separation system, and the obtained lignophenol is a derivative. Can be used to synthesize lignophenol-based compound derivatives with excellent water solubility, especially when aqueous solutions of lignophenol-based compound derivatives and powders of such water-soluble lignophenol-based compound derivatives are added to other powders. It was found that the dispersibility of the resin can be improved, and the present invention has been completed.

  The powder dispersant of the present invention can be prepared using a lignophenol compound isolated in a separation step with cellulose as a raw material. The powdery dispersant of the present invention can be used as a solution by dissolving a lignophenol-based compound derivative in an aqueous solution, and can be used as a dispersant for powdered powder by pulverizing a dried product, It can be used as a dispersibility for powders in various forms. In particular, when used as a cement dispersant, not only can the flowability of cement powder be secured, but also a cement admixture with excellent flowability can be prepared by preparing a cement admixture with a small amount of water. The effect makes it possible to shorten the cement setting time and add strength.

  The first of the present invention is a powder dispersant comprising a water-soluble lignophenol compound derivative. The dispersant for powders of the present invention has lignophenols as a basic skeleton and is derivatized by introducing a substituent etc. into this, and is excellent in water solubility and when mixed with powders, The dispersibility of the body can be improved.

  Lignin is a useful component contained in forest resources together with cellulose and hemicellulose, and is a component that fills cell gaps and acts as an adhesive substance between cells. Although it is a natural product, its chemical structure is not clear, but it is generally a network polymer compound formed by condensation of structural units having phenylpropane as a skeleton. The benzene ring contained in the natural lignin may have a phenolic hydroxyl group and / or an alkoxy group. FIG. 1 shows an example of a structural unit of natural lignin, and FIG. 2 shows the manner of introduction of phenols into the lignophenol basic skeleton. FIG. 3 shows a schematic structural diagram of lignocresol as an example of a lignophenol compound.

  In the present invention, the “lignophenol compound derivative” is a compound containing a lignophenol compound as a part of its structure. Therefore, the thing which introduce | transduced the substituent into the lignophenol type compound, the crosslinked body of a lignophenol type compound, etc. are contained. The “lignophenol compound” is a compound in which phenols are bound to lignin. The bonding position, the number of bonds, the bonding form, etc. of phenols are not limited. “Water-soluble” means that 0.01 to 1,900 g is dissolved in 100 g of ion-exchanged water at a temperature of 25 ° C. within a pH range of 3 to 13.

  The phenols in the present invention are compounds in which at least one phenolic hydroxyl group is bonded. Examples of the monovalent phenol include phenol, o-cresol, m-cresol, p-cresol, 3,5-xylenol, carvacrol, thymol, α-naphthol, β-naphthol and the like. Examples of the divalent phenol include catechol, resorcin, and hydroquinone. Examples of the trivalent phenol that can be suitably used include pyrogallol and phloroglucin. The lignophenol compounds include lignophenol, lignocresol, ligno-2,4-xylenol, ligno-2,6-xylenol, ligno-2-methoxy-4-methylphenol, lignocatechol, lignoresorcin, lignopyroganol. and so on. In the present invention, one or more of these may be bound to lignin. Therefore, lignophenol compounds include compounds in which two or more phenols are added, such as lignophenol cresol, in addition to compounds in which one phenol is added to lignin, such as lignophenol and lignocresol. There may be. The amount of phenols introduced relative to natural lignin is preferably 1 to 60% by mass, more preferably 1 to 55% by mass, and particularly preferably 1 to 50% by mass. If the amount is less than 1% by mass, the amount of functional groups introduced may be reduced, resulting in poor powder dispersibility. On the other hand, when it exceeds 60 mass%, it is disadvantageous in that unreacted phenols remain. The weight average molecular weight of the lignophenol compound can be appropriately selected depending on the type of functional group to be introduced thereafter, but is preferably 1,000 to 1,000,000, more preferably 1,000 to 1,000. 500,000, in particular 2,000 to 100,000. If it is less than 1,000, the dispersibility may be inferior. On the other hand, if it exceeds 1,000,000, it may act as a flocculant, which is disadvantageous. The weight average molecular weight is a value in terms of polyethylene glycol by gel permeation chromatography (hereinafter referred to as GPC).

Column used for GPC measurement conditions: TSK guard column SWXL + TSKgel G4000SWXL + G3000SWXL + G2000SWXL manufactured by Tosoh Corporation
Eluent: A solution prepared by dissolving 115.6 g of sodium acetate trihydrate in a mixed solvent of 10999 g of water and 6001 g of acetonitrile, and adjusting the pH to 6.0 with 30% sodium hydroxide is used.

Implanted amount: 100 μL of 0.5% eluent solution
Eluent flow rate: 0.8 mL / min
Column temperature: 40 ° C
Standard substance: polyethylene glycol, weight average molecular weight (Mw) 272500, 219300, 85000, 46000, 24000, 12600, 4250, 7100, 1470.
Calibration curve order: Tertiary detector: 410 manufactured by Waters, Japan 410 Differential refraction detector analysis software: MILRENNIUM Ver. Manufactured by Waters, Japan 3.21

  The lignophenol compound derivative suitable as the powder dispersant of the present invention includes a compound obtained by introducing various functional groups and long-chain hydrophilic substituents into the above lignophenol compound, a lignophenol compound and / or a lignophenol compound. There are polymers of compound derivatives and cross-linked products thereof.

Examples of functional groups that can be introduced include anionic substituents such as carboxyl groups, sulfonyl groups, and phosphate groups; cationic substituents such as amino groups and amide groups; alkoxy groups, carboxylate esters, phosphate esters, sulfate esters, Nonionic substituents such as a hydroxyl group, a nitrile group, and a thiol group; and an anionic substituent, a cationic substituent, and an organic group partially including the nonionic substituent. In addition, examples of the organic group partially containing the anionic substituent include a carboxyalkyl group, a sulfonylalkyl group, and a phosphoalkyl group, and examples of the organic group partially containing the cationic substituent include an aminoalkyl group. Similarly, as an organic group partially containing a nonionic substituent, when an alkyl group is represented by R, a carboxylate ester-containing group such as —OCH ₂ CH ₂ COOR, —OCH ₂ CH ₂ CN There are carbonitrile groups shown.

In addition, the display of the said functional group shows the case where it substitutes for the hydrogen atom of a lignophenol type compound, and it couple | bonds directly with either. Since the lignophenol compound has at least a phenolic hydroxyl group, various functional groups and / or long-chain hydrophilic substituents can be introduced by reacting with the hydroxyl group. These may be introduced by reacting with a group, and these can also be introduced by the action of a compound capable of reacting with a hydroxyl group or an alkoxy group derived from natural lignin. Therefore, in the case of bonding via a phenolic hydroxyl group (Ph-OH) contained in the lignophenol compound, the functional group is bonded via an oxygen atom. For example, when a carboxymethyl group (—CH ₂ COOH), which is a carboxyalkyl group, is bonded via a phenolic hydroxyl group (Ph—OH), it becomes Ph—OCH ₂ COOH. In addition, the water-soluble lignophenol-type compound derivative may neutralize the acid group contained and may form the salt. Such salts include group 1 elements such as lithium, sodium and potassium; group 2 elements such as magnesium, calcium and barium; protons such as alkanol ammonium and triethylammonium such as ethanolammonium, diethanolammonium and triethanolammonium. Organic ammonium which is a converted organic amine; further ammonium can be used.

  The introduction amount of the anionic substituent described above varies depending on the kind of powder added as a dispersant for powder, but is generally 0.1 to 100 mol% with respect to the hydroxyl group per molecule of lignophenol. Is preferable, more preferably 1 to 100 mol%, particularly 5 to 100 mol%. If it is less than 0.1 mol%, it may be inferior in water solubility.

  In general, the amount of the cationic substituent introduced is preferably from 0.1 to 100 mol%, more preferably from 1 to 100 mol%, particularly from 5 to 100 mol%, based on the hydroxyl group per molecule of lignophenol. It is. If it is less than 0.1 mol%, it may be inferior in water solubility.

  In general, the introduction amount of the nonionic substituent is preferably 0.1 to 100 mol%, more preferably 1 to 100 mol%, particularly 5 to 100 mol%, based on the hydroxyl group per molecule of lignophenol. It is. If it is less than 0.1 mol%, it may be inferior in water solubility.

  Examples of the long-chain hydrophilic substituent that can be introduced into the lignophenol compound used in the present invention include a polyalkylene oxide chain, a homopolymer of a polymerizable monomer or two or more copolymer chains, and a water-soluble polysaccharide. Chain, polyamino acid chain, polyacetal and the like. As the polyalkylene oxide chain introduced into the lignophenol-based compound derivative, those represented by —O— (YO) n—R are suitable. Here, YO represents oxyalkylene, n represents the degree of polymerization of oxyalkylene, and R represents a hydrogen atom or an alkyl group having 1 to 30 carbon atoms. In the present invention, YO is preferably an oxyalkylene having 2 to 4 carbon atoms, and the n oxyalkylenes may be the same or different, and in the case of two or more types, they may be added in a block form and randomly. It may be added to the shape. n is preferably 1 to 200.

  The polymerizable monomer constituting the long-chain hydrophilic substituent includes acrylic acid, methacrylic acid, acrylic ester, methacrylic ester, acrolein, methacrolein, acronitrile, methacrylamide, acrylamide, maleic acid, maleic anhydride , Crotonic acid, isocrotonic acid, fumaric acid, citraconic acid, mesaconic acid and other α, β-unsaturated carbonyl compounds and derivatives thereof. For example, α, β-unsaturated carbonyl compounds and derivatives thereof, unsaturated alcohols having 1 to 30 carbon atoms such as 3-methyl-3-buten-1-ol, (meth) allyl alcohol, and 3-buten-1-ol and so on. In the present invention, in addition to the homopolymer chain of these polymerizable monomers, these two or more copolymer chains may be used. Among these, in the present invention, it is preferable to add a polymer chain containing at least one of acrylic acid, methacrylic acid, (meth) allyl alcohol, and 3-methyl-3-buten-1-ol. The long-chain hydrophilic group introduced into the ligphenol-based compound preferably has a derived compound solubility of 0.01 to 95% by mass, more preferably 0.01 to 70% by mass.

  Water-soluble polysaccharide chains include cellulose, cellulose acetate, methyl cellulose, ethyl cellulose, methyl ethyl cellulose, hemicellulose, starch, methyl starch, ethyl starch, methyl ethyl starch, agar, carrageenan, alginic acid, pectic acid, guar gum, tamarind gum, locust bean There are gum, konjac mannan, dextran, xanthan gum, pullulan, gellan gum, chitin, chitosan, chondroitin sulfate, heparin, hyaluronic acid and the like, and water-soluble polysaccharides include compounds obtained by carboxyalkylating and hydroxyalkylating polysaccharides. Specific examples include carboxymethyl cellulose, hydroxyethyl cellulose, starch glycolic acid, agar derivatives, carrageenan derivatives and the like. These water-soluble polysaccharides may be used alone or in combination of two or more. The water-soluble polysaccharide chain introduced into the ligphenol-based compound preferably has a solubility of the derived compound of 0.01 to 95% by mass, more preferably 0.01 to 70% by mass.

  The polyamino acid chain is composed of a polypeptide obtained by dehydration condensation of amino acids. The amino acids that can be used are alanine, valine, leucine, isoleucine, methionine, tryptophan, phenylalanine, proline, glycine, serine, threonine, cysteine, tyrosine, asparagine, glutamine, lysine, histidine, arginine, aspartic acid, glutamic acid, phenylalanine, proline. , Serine, cystine, aspartic acid, glutamic acid, L-cysteic acid, L-ornithine, γ-aminobutyric acid, ω-esters of acidic amino acids, and N-substituted products of basic amino acids. These amino acids and derivatives thereof may be optically active (L-form, D-form) or racemic. Examples of amino acid derivatives further include amino groups, carboxyl groups, phosphate groups, nitro groups, hydroxyl groups, sulfone groups and other functional groups, ester bonds, amide bonds, thioester bonds, imides, and the like. These amino acids and derivatives thereof may be used alone or in combination of two or more.

  The polyamino acid chain used in the present invention may be one in which a monomer component of another copolymer is bound in addition to the monomer component. Examples of such other monomer components include aminocarboxylic acid, succinimide, aminosulfonic acid, aminophosphonic acid, hydroxycarboxylic acid, mercaptocarboxylic acid, mercaptosulfonic acid, mercaptophosphonic acid, and the like. Furthermore, polyvalent amine, polyhydric alcohol, polyvalent thiol, polyvalent carboxylic acid, polyvalent sulfonic acid, polyvalent phosphonic acid, polyvalent hydrazine compound, polyvalent carbamoyl compound, polyvalent sulfonamide compound, polyvalent phosphonamide compound Polyvalent epoxy compounds, polyvalent isocyanate compounds, polyvalent isothiocyanate compounds, polyvalent aziridine compounds, polyvalent carbamate compounds, polyvalent carbamic acid compounds, polyvalent oxazoline compounds, polyvalent reactive unsaturated bond compounds, A valent metal etc. are also mentioned. In the present invention, it is preferable to use a crosslinked body of polyaspartic acid, a crosslinked body of polyglutamic acid, or a crosslinked body of polylysine. The polyamino acid chain introduced into the ligphenol-based compound preferably has a solubility of the derived compound of 0.01 to 95% by mass, more preferably 0.01 to 70% by mass.

  The polyacetal is a polymer having an acetal bond as a main chain, and is a polymer of aldehydes such as formaldehyde and acetaldehyde, and α-polyoxymethylene, β-polyoxymethylene, γ-polyoxymethylene, δ-poly Examples include oxymethylene, ε-polyoxymethylene, and polyglyoxylic acid. In the present invention, polyglyoxylic acid can be preferably used. The solubility of the derived compound in the polyacetal chain introduced into the ligphenol-based compound is preferably 0.01 to 95% by mass, more preferably 0.01 to 70% by mass.

  In addition, the anionic functional group, nonionic functional group, and cationic functional group may be further bonded to the long-chain hydrophilic substituent.

  The lignophenol-based compound derivative may be a cross-linked product of a lignophenol-based compound, for example, one obtained by acting a compound having at least two functional groups capable of reacting with the lignophenol-based compound. In addition, the crosslinked body of a lignophenol type compound derivative may be sufficient.

  For use as a dispersant for powders in the present invention, a lignophenol-based compound preferably having an anionic functional group such as a carboxyl group or a sulfonic acid group introduced therein, a carboxylic acid that can be hydrolyzed to generate an acid group Those into which a long-chain hydrophilic substituent such as a polyalkylene oxide chain is introduced, such as an ester group, a phosphate ester group and a sulfate ester group, are preferred. When the lignophenol compound derivative has an anionic group when added to the hydrophilic powder, the anionic group is adsorbed on the surface of the hydrophilic powder particles, and the aggregation of the particles is suppressed and excellent dispersion is achieved. It is because it can exhibit sex. A derivative in which a long-chain hydrophilic substituent is introduced to ensure water solubility is preferable because it has excellent powder dispersibility and also ensures dispersibility of the powder and powder composition in an aqueous solution. In particular, when the above water-soluble lignophenol compound derivative is used as a cement dispersant, a uniform cement composition can be prepared even when mixed with a small amount of water at the time of cement use. The fluidity can be secured, and the cement setting time can be shortened by the water reducing effect after the cement is buried. Similarly, carboxylic acid ester groups, phosphoric acid ester groups, and sulfuric acid ester groups that can be hydrolyzed to generate acid groups are rapidly hydrolyzed by the addition of an alkaline substance under an aqueous medium, and are hydrophilic. Since the carboxy ions are expressed, when used as a dispersant in alkaline materials such as cement, the dispersibility and fluidity of the cement composition can be secured, and the hardening time of the cement composition can be shortened by the water reducing effect. preferable. In addition, as a dispersant for powder blended in a cement composition, depending on the combined effect, it is called a cement dispersant, a cement water reducing agent, a cement thickener, a cement separation reducing agent, a drying shrinkage reducing agent, etc. Is done. In this invention, it can use suitably for any use by selecting the characteristic of this derivative.

  In the present invention, the functional group, long-chain hydrophilic group and the like may be substituted with any of lignophenol compounds as described above. Below, an example of the structure of the water-soluble lignophenol-type compound derivative which can be used conveniently by this invention is shown. These can be suitably used particularly as a cement dispersant.

  The powder dispersant of the present invention may be in any dosage form. Therefore, it may be a solution in which the water-soluble lignophenol compound derivative is dissolved, or the water-soluble lignophenol compound derivative may be dried and sized to form a powder or granule. In the case of a liquid preparation, the concentration of the water-soluble lignophenol compound derivative contained is not limited, and can be appropriately selected depending on the type of derivative, viscosity after dissolution, stability in solution, and the like. Generally, it is 0.01-95 mass%. When it exceeds 95% by mass, the viscosity becomes too high, and it may be difficult to mix with powder.

  On the other hand, in the case of a powder agent, the average particle size is generally 10 to 1,000 μm, preferably 20 to 500 μm, more preferably 50 to 100 μm, although it varies depending on the kind of powder to be mixed and its particle size. . When the average particle size is out of the above range, the mixing property with the powder may be lowered. The lignophenol compound derivative used in the present invention can bind 1 to 6 moles of phenols with respect to 1 mole of phenylpropane constituting the natural lignin, and the bound phenols are substituted with a high yield. Groups can be introduced. For this reason, the dispersibility is higher than that of the conventional lignin compound derivative.

  In the powder dispersant of the present invention, the above-mentioned water-soluble lignophenol compound derivative can be used as it is as a dispersant for powder, but other known cement dispersants and Other additives can be blended. Examples of such additives include air entraining agents, cement wetting agents, swelling agents, waterproofing agents, retarders, quick setting agents, water-soluble polymer substances, thickeners, flocculants, drying shrinkage reducing agents, and strength enhancers. , Curing accelerators, antifoaming agents, polymer emulsions, waterproofing agents, rustproofing agents and the like.

  The amount of the dispersant for powder of the present invention used may be 0.1 to 50% by mass, more preferably 0, in terms of water-soluble lignophenol compound derivative, based on 100 parts by mass of the powder. 0.1 to 25% by mass, particularly preferably 0.1 to 10% by mass. If it is less than 0.1% by mass, it may be difficult to exhibit dispersibility. On the other hand, if it exceeds 50% by mass, the dispersibility will not change, but the addition of a large amount will affect the powder dispersant itself. There is a case.

  The dispersant for powder of the present invention can be suitably used as a cement dispersant, a pigment dispersant, a dye dispersant, and a paint dispersant.

  The cement dispersant of this invention can be mix | blended with a general hydraulic cement. Therefore, special Portland cements such as early-strength Portland cement, low heat generation Portland cement, high iron oxide Portland cement, white Portland cement, ordinary Portland cement, natural cement, Roman cement, hydraulic lime, lime mixed cement, mixed Portland cement Can be blended with cement, alumina cement, cement with high belite content, various mixed cements, and the like.

  The addition amount of the cement dispersant of the present invention is preferably 0.1 to 20% by mass, more preferably 0.1 to 10% by mass, in terms of solid content with respect to cement. Moreover, when using the cement dispersant of this invention as a hardening accelerator or a quick setting agent, it is preferable that it is 0.1-20 mass% in solid content conversion value with respect to cement, More preferably, it is 0.1 10% by mass. When cement and water are added to the cement dispersant of the present invention, a cement paste is obtained, and this is combined with sand as a fine aggregate or pebbles as a coarse aggregate, and a cement composition such as mortar or concrete. Can be prepared.

  There is no limitation on the method for producing the powder dispersant of the present invention and the water-soluble lignophenol compound derivative used in the present invention, and any method can be used. Hereinafter, a production method suitable for the present invention will be described.

(1) Synthesis of lignophenol compound The lignophenol compound used as a raw material is a compound in which phenols are bound to lignin. The production method may be any, and it may be produced by a conventionally known method, and a commercially available product may be purchased. In order to produce such a lignophenol compound, for example, acetone defatted pulverized plant is allowed to sorb 1 to 10 mole times cresol per lignin, then sulfuric acid is added to the sorbed sample and stirred. Add cresol to the hydroxyl group of lignin. As a result, generally, phenols are bonded to the α-position, β-position, and γ-position as shown in FIG. A large excess of water is added thereto, the insoluble precipitate is centrifuged, and sulfuric acid and unreacted cresol are washed away with water and dried. After adding acetone to this and stirring for a whole day and night, the insoluble matter is centrifuged, then concentrated with an evaporator, dripped into a large excess of diethyl ether, and the insoluble precipitate is centrifuged and washed to obtain lignocresol. it can. If other phenols such as phenol, 3,5-xylenol, naphthol, catechol, pyrogallol are used instead of cresol, the corresponding lignophenols can be obtained. In addition, when an alkaline aqueous solution such as sodium hydroxide is allowed to act on lignophenol and allowed to act at a temperature of 140 ° C. or higher for 0.5 to 12 hours, the molecular weight of lignocresol can be reduced. If the reaction time or alkali concentration is adjusted, the molecular weight can also be adjusted.

  The present invention is characterized in that a lignophenol compound is used as a raw material for the derivative. However, the lignophenol compound is easy to prepare a derivative having excellent dispersibility, and a natural lignin is produced by acting phenols on plant resources. This is because the lignophenol compound can be easily separated from cellulose. Moreover, since phenols having excellent reactivity are added, lignophenol compound derivatives having different characteristics can be easily synthesized. In the present invention, it has been found that among such lignophenol compound derivatives, those having excellent water solubility can be suitably used as a powder dispersant. Natural lignin also contains a phenolic hydroxyl group, but the present invention is characterized in that the above functional group is introduced into the phenolic hydroxyl group added in a large amount to natural lignin, thereby forming a derivative having excellent powder dispersibility. is there.

(2) Carboxyalkylation Taking carboxymethylation as an example, a lignophenol compound or an alkali-treated lignophenol compound is dispersed in a solvent such as isopropyl alcohol, and an aqueous sodium hydroxide solution is added and allowed to stand. Add isopropyl alcohol to this and leave it still. This heterogeneous mixed solution is maintained at a temperature of 20 to 90 ° C. with stirring, a liquid obtained by dissolving monochloroacetic acid in isopropyl alcohol is gradually added, and further stirred at a temperature of 20 to 90 ° C. for 1 to 10 hours. The reaction solution is separated into a massive precipitate of a lignin derivative containing sodium hydroxide and an alcohol solution containing a partially dissolved lignin derivative. The alcohol solution is distilled off with an evaporator or the like, and the dissolved product is dried. The precipitate formed by neutralizing the dried solid with hydrochloric acid is removed by centrifugation or the like, and the supernatant is recovered to obtain a carboxymethylated form of a lignophenol compound.

(3) Addition of alkylene oxide When alkylene oxide is added to a lignophenol compound to which a catalytic amount of base has been added, ring-opening polymerization of alkylene oxide proceeds from the alkoxide moiety generated by the hydroxyl group and base, and a polyalkylene oxide chain is added. Is done. Further, a compound having an epoxy and an unsaturated bond bifunctional group in a substrate such as allyl glycidyl ether or glycidyl (meth) acrylylate is added to a lignophenol compound to which a catalytic amount of a base has been added, There is a method in which ring-opening addition is performed with an epoxy group to add a reactive unsaturated bond to lignophenol, and then copolymerized with a polymerizable monomer having a long-chain hydrophilic substituent.

(4) Introduction of a sulfonyl group into a lignophenol compound To introduce a sulfonyl group into a lignophenol compound, the lignophenol compound is heated at 130 to 170 ° C in a bisulfite solution having a pH of 1-2. Moreover, after dissolving lignophenol in alkaline aqueous solution, persulfate, such as ammonium persulfate and potassium persulfate, is added and a sulfonyl group can be introduce | transduced even if it heats at 50-100 degreeC for 1 to 10 hours.

(5) Other functional groups For example, to produce a derivative containing a carboxylate ester-containing organic group, a sulfate ester-containing organic group, a phosphate ester-containing organic group, etc., for example, lignophenol according to the above (3) Acrylic acid is allowed to act on a compound, and a polymerizable monomer containing a carboxylic acid ester, a polymerizable monomer containing a sulfate ester, and a polymerizability containing a phosphate ester via a double bond of the acrylic acid It can be prepared by polymerizing or adding monomers. Further, a compound having an epoxy and an unsaturated bond bifunctional group in a substrate such as allyl glycidyl ether or glycidyl (meth) acrylylate is added to a lignophenol compound to which a catalytic amount of a base has been added, Perform ring-opening addition with an epoxy group to add a reactive unsaturated bond to lignophenol, and then react with a polymerizable monomer containing a carboxylate ester or sulfate ester or a polymerizable monomer containing a phosphate ester Then, these groups can be introduced.

  Examples of such polymerizable monomers include sulfonic acid group-containing polymerizable monomers such as vinyl sulfonic acid, styrene sulfonic acid, sulfoethyl (meth) acrylate, allyl sulfonic acid, and methallyl sulfonic acid, methyl acrylate, acrylic Carboxylic acid ester group-containing polymerizable monomers such as ethyl acrylate and hydroxyethyl acrylate, 2- (meth) acryloyloxyethyl acid phosphate, 2- (meth) acryloyloxypropyl acid phosphate, 2- (meth) acryloyloxy- Examples thereof include acidic phosphate group-containing polymerizable monomers such as 3-chloropropyl acid phosphate and 2- (meth) acryloyloxyethyl phenyl phosphate. In the present invention, one of these can be used alone, or two or more can be used in combination.

(6) Crosslinked product of lignophenol compound and / or lignophenol compound derivative An alkaline solution such as sodium hydroxide is allowed to act on the crosslinked product of lignophenol compound and / or lignophenol compound derivative to dissolve completely. When a crosslinking agent is added to this solution and reacted at a temperature of 0 to 100 ° C., a gelled product is obtained. As the cross-linking agent, compounds having two or more functional groups capable of reacting with functional groups contained in the cross-linked product of lignophenol compound and / or lignophenol compound derivative can be widely used. Polyalkylene glycol diglycidyl ether such as glycol diglycidyl ether, polypropylene glycol diglycidyl ether, diethylene glycol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di ( (Meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythrito Lutri (meth) acrylate, pentaerythritol tetra (meth) acrylate, (poly) propylene glycol di (meth) acrylate, glycerin tri (meth) acrylate, glycerin acrylate methacrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, pentaerythritol Tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, triallyl cyanurate, triallyl isocyanurate, triallyl phosphate, triallylamine, poly (meth) allyloxyalkane, glycerol diglycidyl ether, ethylene glycol, polyethylene glycol , Propylene glycol, glycerin, pentaerythritol, ethylenediamine, polyethyleneimi , Glycidyl (meth) acrylate, triallyl isocyanurate, trimethylolpropane di (meth) allyl ether, tetraallyloxyethane, glycerol propoxy triacrylate and the like. Two or more of these crosslinking agents may be used. The amount used is preferably 0.1 to 10,000% by mass, more preferably 10 to 10,000% by mass, and most preferably 10 to 5,000% by mass with respect to the lignophenol compound.

(7) Powder Dispersant To obtain a liquid powder dispersant from the above lignophenol compound derivative, the reaction solution may be used as a powder dispersant as it is. At this time, a viscosity adjusting agent, a pH adjusting agent and the like may be added.

  On the other hand, in order to obtain powders and granules, the obtained lignophenol-based compound derivatives include ACM pulverizer (Hosokawa Micron Corporation), turbo mill (Turbo Industry Co., Ltd.), Fitzmill (Hosokawa Micron Corporation), roll granulator ( It can be pulverized by pulverization into powder, granule, etc. by a pulverizer such as Nippon Granulator Co., Ltd. In addition, when mix | blending another additive with the dispersing agent for powders, you may add by a grinding | pulverization process or a sizing process, and may add after pulverization.

  Next, an Example is given and this invention is demonstrated concretely. However, these examples do not limit the present invention.

Example 1
3.48 g of 48 mass% sodium hydroxide was added to 1 g of lignocresol, and stirring was continued until a uniform slurry was formed. To the resulting slurry, 20 g of 1,4-dioxane was added as a solvent to disperse the slurry. The slurry dispersion was heated to 70 ° C., and 2 g of 1,4-dioxane in which 1.3 g of chloroacetic acid was dissolved was added dropwise over 30 minutes. As the reaction progressed, the slurry agglomerated, but when the agglomeration was severe, the dripping was stopped, the agglomerate was broken, and the dripping was resumed. After dropping, the mixture was aged at 70 ° C. for 2 hours. After cooling, 1,4-dioxane as a solvent was filtered off. The remaining solid was washed with cyclohexane and 100 g of water was added. Since the pH was alkaline, it was neutralized with 10% by mass of diluted hydrochloric acid. Since the reaction product was soluble in water even under neutral conditions, the insoluble matter contained was removed to obtain a water-soluble reaction product.

  After condensing the reaction product solution with an evaporator, desalting was performed using a dialysis membrane having a molecular weight of 1,000 in order to remove NaCl remaining in the system. The solution after desalting was concentrated to obtain a black-brown aqueous solution containing modified lignophenol. This is designated as powder dispersant (1). The solubility of the dispersant (1) was 0.01 to 95% by mass, and the molecular weight was MW; 10,000 to 100,000.

(Example 2)
To 2 g of lignocresol, 2 g of 30% by mass sodium hydroxide and 20 g of ion-exchanged water were added, and stirring was continued until a uniform aqueous solution was obtained. To the resulting aqueous solution, 0.5 g of ammonium persulfate was added and heated to 60 ° C., followed by stirring for 6 hours.

The reaction product solution was condensed with an evaporator, and then desalted using a dialysis membrane having a molecular weight of 1,000 in order to remove sodium sulfate remaining in the system. The solution after desalting was concentrated to obtain a black-brown aqueous solution containing modified lignophenol. Let aqueous solution after reaction be the dispersing agent for powders (2). The solubility of the dispersant (2) was 0.01 to 95% by mass, and the molecular weight was MW; 10,000 to 100,000.

(Example 3, Comparative Example 1, Comparative Example 2)
The amount of water added to the cement composition of the powder dispersants (1) and (2) obtained in Example 1 and Example 2, the flow value, the water reduction rate, and the amount of air in the cement composition were measured. For comparison, the same operation was performed by adding lignophenol before modification (Comparative Example 1) and lignin sulfonic acid (Comparative Example 2) instead of the powder dispersant (1). The results are shown in Table 1. In addition, the measuring method of each item followed the following method.

(1) Flow value The flow value is an index indicating the water reducing performance of the cement dispersant, and was evaluated by the flow value of the cement composition after kneading for 3 minutes and 30 seconds under the condition of 20 ° C.

(I) Cement test material Adjustment of the cement composition required for the flow test was performed using the following materials.

Normal Portland cement (made by Taiheiyo Cement); 200g
Fine aggregate (Toyoura standard sand: JIS R 5201); 400 g
Ion-exchanged water containing 0.3% by mass of cement dispersant (1) and 2% by mass of antifoaming agent (using the trade name “MA404” (polyalkylene glycol derivative) of NMB) based on cement; 130 g

(Ii) Method for preparing cement composition To a Hobart type mortar mixer (model number N-50, manufactured by Hobart), 200 g of ordinary Portland cement and 400 g of fine aggregate were added and kneaded at a low speed for 25 seconds. Between 25 seconds and 30 seconds from the start of kneading, 130 g of ion-exchanged water containing the cement dispersant (1) and the antifoaming agent was added, and after 30 seconds from the start of kneading, the mixture was kneaded at a medium speed. The cement composition attached to the wall of the ball was kneaded at a medium speed for 1 minute (1 minute and a half from the start of kneading) (15 seconds), and kneaded again at a medium speed. A cement composition was obtained 3 minutes and 45 seconds after the start of kneading (kneading time 3 minutes and a half).

(Iii) Method for measuring flow value After the obtained cement composition was put into a stainless steel cylinder having a height of 5 cm and an inner diameter of 5.4 cm in two portions, and 10 times with a glass rod each time, The cement composition at the top of the cylinder was leveled. The cylinder was lifted over 2-3 seconds. Since the cement composition spreads naturally, the longest part of the spread cement composition and the length of the position perpendicular to the longest part were measured to obtain a flow value.

(2) Measurement of air amount The weight when the volume of the adjusted cement composition was 500 ml was measured, and the air amount was measured from the specific gravity of the material used.

(3) Amount of water added The amount of ion-exchanged water added so that the flow value of the cement composition was 100 mm without using the cement dispersant (1) was determined.

  To a Hobart type mortar mixer (model number N-50, manufactured by Hobart), 200 g of ordinary Portland cement, 400 g of fine aggregate, and 4 g of an antifoaming agent were added and kneaded at a low speed for 25 seconds. Between 25 seconds and 30 seconds from the start of kneading, ion exchange water was added, and after 30 seconds from the start of kneading, the mixture was kneaded at a medium speed. The cement composition attached to the wall of the ball was kneaded at a medium speed for 1 minute (1 minute and a half from the start of kneading) (15 seconds), and kneaded again at a medium speed. A cement composition was obtained 3 minutes and 45 seconds after the start of kneading (kneading time 3 minutes and a half). Using this cement composition, the amount of ion-exchanged water added was adjusted, and the amount of water at which the flow value of the cement composition reached 100 mm was determined.

(4) Method for measuring water reduction performance The cement dispersant (1) prepared in Example 1 is contained in an amount of 0.3% by mass with respect to cement, and the flow value of the cement composition is 100 mm in the same manner as in (3) above. The amount of added water was determined.

  To a Hobart type mortar mixer (model No. N-50, manufactured by Hobart), 200 g of ordinary Portland cement, 400 g of fine aggregate, 0.6 g of the cement dispersant (1), and 4 g of the antifoaming agent are added and kneaded at a low speed for 25 seconds. did. Between 25 seconds and 30 seconds from the start of kneading, ion exchange water was added, and after 30 seconds from the start of kneading, the mixture was kneaded at a medium speed. The cement composition attached to the wall of the ball was kneaded at a medium speed for 1 minute (1 minute and a half from the start of kneading) (15 seconds), and kneaded again at a medium speed. A cement composition was obtained 3 minutes and 45 seconds after the start of kneading (kneading time 3 minutes and a half). Using this cement composition, the amount of ion-exchanged water added was adjusted, and the amount of water at which the flow value of the cement composition reached 100 mm was determined. This is the amount of water after water reduction. On the other hand, the amount of water obtained in (3) above and the amount of water before water reduction are used. The water reduction rate was calculated according to the following formula using the water amount before water reduction and the water amount after water reduction.

Example 4
When dispersed (1) for powder obtained in Example 1 was dehydrated with an evaporator, a blackish brown powder was obtained. After drying under reduced pressure, it was made into fine powder in a mortar. The particle size of the obtained powder was measured in a batch system using a laser diffraction / scattering type particle size distribution apparatus LA-910 (Horiba, Ltd.), using ethanol as a dispersion solution and ultrasonically dispersing. The obtained particle size was 19.2 μm in terms of average particle size (volume basis). In addition, the dispersion | distribution solvent at the time of a measurement should just be a thing which does not melt | dissolve a lignophenol type compound derivative, Since the disperse | distributed for powder (1) is lignophenol insoluble in water, water was utilized for the solvent.

  The dispersant for powder comprising the water-soluble lignophenol compound derivative of the present invention is excellent in dispersibility and is particularly useful as a cement dispersant.

It is a figure which shows an example of the structural unit of natural lignin. It is a figure which shows (alpha) -position, (beta) -position, and (gamma) -position in case cresol substitutes. It is a figure which shows the schematic structure figure of a conifer lignocresol.

Claims (6)

A powder dispersant comprising a water-soluble lignophenol compound derivative having an anionic functional group . The dispersant for powder according to claim 1, wherein the anionic functional group is a carboxyl group, a sulfonyl group, a phosphate group, a carboxyalkyl group, a sulfonylalkyl group, or a phosphoalkyl group. The derivative is represented by the following formula:
-O- (YO) n-R
In the formula, YO is oxyalkylene having 2 to 4 carbon atoms, R is a hydrogen atom or an alkyl group having 1 to 30 carbon atoms, n represents the degree of polymerization of oxyalkylene, and is 1 to 200.
The dispersing agent for powders of Claim 1 or 2 which has a polyalkylene oxide chain represented by these.   The powder dispersant according to any one of claims 1 to 3, wherein the solvent contains 0.1 to 95% by mass of the lignophenol compound derivative.   The dispersant for powder according to any one of claims 1 to 3, wherein the lignophenol compound derivative has an average particle size of 10 to 1,000 µm.   A cement dispersant comprising the dispersant for powder according to any one of claims 1 to 5.

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