JP5806558B2 - Dispersant - Google Patents

Description

The present invention relates to a dispersant using kraft lignin.

So far, lignin, which is one of the main components of wood, has been used in many applications in the form of lignin derivatives by applying various modifications. For example, lignin sulfonic acid is widely used as a cement dispersant. Further, for example, Patent Document 1 discloses that when lignin sulfonic acid is used as a cement dispersant, a derivative modified with an acrylic or vinyl monomer is used. On the other hand, Patent Document 2 discloses a resin composition obtained by further crosslinking a polymer obtained by grafting acrylic acid to kraft lignin with an aldehyde, mainly for a binder. Furthermore, Patent Document 3 discloses a resin composition particularly suitable as a dispersant or a scale inhibitor obtained by grafting a vinyl monomer to lignin, for example, lignin sulfonic acid.
Furthermore, Patent Document 4 contains a lignin derivative having at least one structural unit derived from kraft lignin and / or a salt thereof and at least one structural unit derived from at least one water-soluble monomer. Dispersants characterized by are disclosed.

JP-A-1-145358 US 2002/0065400 US Pat. No. 4,891,415 Special table 2008-514402 gazette

However, the conventional lignin derivatives such as lignin sulfonic acid have a problem that, for example, the ability to disperse cement is not so high when used as a dispersant. Therefore, it is required to effectively enhance the dispersion performance inherent to the lignin skeleton by chemical modification and effectively utilize the lignin derivative as a dispersant exhibiting high dispersion performance. There is also a need to develop new lignin derivatives from kraft lignin, which is only used as a pulp mill fuel.
Under the circumstances described above, the problem to be solved by the present invention is to provide a dispersant exhibiting high dispersion performance using a lignin derivative obtained from kraft lignin discharged during pulp production.

As a result of various studies, the present inventors have found that a specific lignin derivative obtained from kraft lignin exhibits high dispersion performance, and have completed the present invention.

That is, the present invention provides at least one structural unit (A) derived from kraft lignin and / or a salt thereof, a structural unit derived from a polyalkylene oxide chain (B), and a structural unit derived from a monomer having an anionic functional group. (C), the ratio of (A) / {(B) + (C)} is 100 / 0.1 to 100/1000 wt% (mass%) and the ratio of (B) / (C) is A dispersing agent characterized by containing a lignin derivative that is 100/0 to 95/5 wt% (mass%) is provided. In the dispersant of the present invention, the lignin derivative is preferably a monomer having a polyalkylene oxide chain and / or an alkylene oxide and an anionic functional group in the presence of kraft lignin and / or a salt thereof. Obtained by reacting the body. The dispersant of the present invention is suitable as a cement dispersant, for example.
The present invention is described in detail below.
A combination of two or more preferred embodiments of the present invention described below is also a preferred embodiment of the present invention.

≪Dispersant≫
The dispersant of the present invention is a composition derived from a monomer having at least one structural unit (A) derived from kraft lignin and / or a salt thereof, a structural unit (B) derived from a polyalkylene oxide chain, and an anionic functional group. The unit (C) has a ratio of (A) / {(B) + (C)} of 100 / 0.1 to 100/1000 wt% and a ratio of (B) / (C) of 100/0. It is characterized by containing a lignin derivative which is ˜95 / 5 wt%. Here, “kraft lignin” is a water-insoluble compound obtained by allowing a mixed aqueous solution of sodium hydroxide and sodium sulfide to act on wood, having hydroxyphenylpropane as a basic unit, phenolic hydroxy group and It means a compound having a functional group such as alcoholic hydroxy group or thiol group. In addition, the “structural unit derived from kraft lignin and / or a salt thereof” means a portion derived from kraft lignin and / or a salt thereof as a raw material in the molecular structure of the lignin derivative. Furthermore, the “structural unit (B) derived from a polyalkylene oxide chain” refers to a monomer having a polyalkylene oxide chain to be reacted with kraft lignin and / or a salt thereof as a raw material in the molecular structure of a lignin derivative and / or Or the part derived from the alkylene oxides made to react is meant. Further, the “structural unit (C) derived from a monomer having an anionic functional group” has an anionic functional group that reacts with kraft lignin and / or a salt thereof as a raw material in the molecular structure of the lignin derivative. The part derived from a monomer (C) is meant.

<Lignin derivative>
The “lignin derivative” is a monomer having a polyalkylene oxide chain and / or reacted with a functional group such as a phenolic hydroxy group, an alcoholic hydroxy group or a thiol group contained in kraft lignin and / or a salt thereof. A monomer having a polyalkylene oxide chain after reacting with an alkylene oxide and a monomer having an anionic functional group or by generating a radical by reacting kraft lignin and / or a salt thereof with a radical initiator And a compound obtained by reacting a monomer having an anionic functional group, the monomer having a structural unit (A) derived from kraft lignin and / or a salt thereof and a polyalkylene oxide chain (B) and A structural unit derived from a monomer (C) having an anionic functional group The ratio (A) / {(B) + (C)} is 100 / 0.1 to 100/1000 wt% and the ratio (B) / (C) is 100/0 to 95/5 wt%. It means a certain compound. In addition, when the monomer having a polyalkylene oxide chain and the monomer having an anionic functional group have a polymerizable double bond, the structural unit derived from these monomers is the polymerization of each monomer. This corresponds to a structure in which a sex double bond is opened (a structure in which a double bond (C═C) is a single bond (—C—C—)).

The mass average molecular weight of the lignin derivative is not particularly limited, but is preferably 1,000 or more in terms of polyethylene glycol as a value measured by gel permeation chromatography (hereinafter sometimes referred to as “GPC”). It is 500,000 or less, More preferably, it is 5,000 or more and 300,000 or less, More preferably, it is 10,000 or more and 150,000 or less. If a lignin derivative having such a mass average molecular weight is used, a dispersant exhibiting higher dispersion performance can be obtained.

The blending amount of the lignin derivative in the dispersant of the present invention is preferably 50% by mass or more and 100% by mass or less, more preferably 70% by mass or more and 100% by mass or less, more preferably with respect to the total mass of the dispersant. It is 90 mass% or more and 100 mass% or less. When the blending amount of the lignin derivative is less than 50% by mass, the high dispersion performance of the lignin derivative may not be sufficiently exhibited.

<Production of lignin derivative>
Kraft lignin and / or a salt thereof as a raw material for the lignin derivative is not particularly limited as long as it is obtained by allowing a mixed aqueous solution of sodium hydroxide and sodium sulfide to act on wood. Examples of wood used as a raw material for kraft lignin and / or its salts include conifers such as spruce, red pine, cedar and cypress, and broad-leaved trees such as birch and beech. These woods may be used alone or in combination of two or more.

In order to produce a lignin derivative, as described above, for example, a monomer having a polyalkylene oxide chain in a functional group such as a phenolic hydroxy group, an alcoholic hydroxy group or a thiol group contained in kraft lignin and / or a salt thereof. And / or an alkylene oxide and a monomer having an anionic functional group may be reacted. Thus, kraft lignin and / or a salt-derived constituent unit and a polyalkylene oxide chain-containing monomer and / or an alkylene oxide and a monomer-containing constituent unit derived from an anionic functional group are introduced into the lignin derivative. The

Of the functional groups contained in kraft lignin and / or its salts, it reacts with a phenolic hydroxy group or an alcoholic hydroxy group, and examples of the alkylene oxides include alkylene oxides such as ethylene oxide and propylene oxide. These alkylene oxides may be used alone or in combination of two or more.

Alternatively, a monomer having a radically polymerizable polyalkylene oxide chain and an anionic functional group are included in a functional group such as a phenolic hydroxy group, an alcoholic hydroxy group or a thiol group contained in kraft lignin and / or a salt thereof. Monomers may be reacted. As the monomer having a radically polymerizable polyalkylene oxide chain and the monomer having an anionic functional group, for example, those listed below can be used. These monomers having a radically polymerizable polyalkylene oxide chain and monomers having an anionic functional group may be used alone or in combination of two or more.

The monomer having a polyalkylene oxide chain is an alkyl (poly) obtained by adding 1 to 500 moles of an alkylene oxide having 2 to 18 carbon atoms to an alcohol having 1 to 30 carbon atoms or an amine having 1 to 30 carbon atoms. an alkylene glycol, maleic acid, fumaric acid, itaconic acid, di-esters of unsaturated dicarboxylic acids such as citraconic acid; maleic acid, fumaric acid, itaconic acid, and unsaturated dicarboxylic acids such as citraconic acid, 2 carbon atoms to 18 glycol or di esters of polyalkylene glycols of the addition mole number 2 to 500 of these glycols; 1-500 mols of alkylene oxide having 2 to 18 carbon atoms in the alcohol carbon atom number of 1 to 30 Alkoxy (poly) alkylene glycol, and (meth) acrylic acid, crotonic acid To unsaturated monocarboxylic acids such as (meth) acrylic acid, such as (poly) ethylene glycol monomethacrylate, (poly) propylene glycol monomethacrylate, (poly) butylene glycol monomethacrylate, etc. 1-500 mol adducts of alkylene oxides of 2-18 carbon atoms.
An alkylene oxide addition compound of an unsaturated alcohol obtained by adding 2 to 300 mol of alkylene oxide to an unsaturated alcohol such as allyl alcohol, methallyl alcohol, or 3-methyl-3-buten-1-ol.

As monomers having an anionic functional group, as carboxyl group-containing monomers, unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid, and their monovalent metal salts, divalent metal salts, ammonium Salts, organic ammonium salts; unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid, and anhydrides thereof, monovalent metal salts, divalent metal salts, ammonium salts, organic ammonium salts; maleic acid, Half esters of unsaturated dicarboxylic acids such as fumaric acid, itaconic acid, citraconic acid and alcohols having 1 to 30 carbon atoms; unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid, and carbon atoms Half amides with amines of 1 to 30;
As sulfonic acid group-containing monomers, vinyl sulfonate, (meth) allyl sulfonate, 2- (meth) acryloxyethyl sulfonate, 3- (meth) acryloxypropyl sulfonate, 3- (meth) acryloxy-2-hydroxypropyl sulfonate 3- (meth) acryloxy-2-hydroxypropylsulfophenyl ether, 3- (meth) acryloxy-2-hydroxypropyloxysulfobenzoate, 4- (meth) acryloxybutylsulfonate, (meth) acrylamidomethylsulfonic acid, ( Unsaturated sulfonic acids such as (meth) acrylamidoethylsulfonic acid, 2-methylpropanesulfonic acid (meth) acrylamide, styrenesulfonic acid, sodium 2-hydroxy-3-allyloxy-1-propanesulfonate; Each time, their monovalent metal salts, divalent metal salts, ammonium salts and organic ammonium salts.
As phosphoric acid group-containing monomers, 3- (meth) acryloyloxypropylphosphonic acid, 4- (meth) acryloyloxybutylphosphonic acid, 5- (meth) acryloyloxypentylphosphonic acid, 6- (meth) acryloyloxyhexyl Phosphonic acid, 7- (meth) acryloyloxyheptylphosphonic acid, 8- (meth) acryloyloxyoctylphosphonic acid, 9- (meth) acryloyloxynonylphosphonic acid, 10- (meth) acryloyloxydecylphosphonic acid, 4- ( (Meth) acryloyloxy-2-methylbutylphosphonic acid, 4- (meth) acryloyloxy-2-methylbutylphosphonic acid, and monovalent metal salts, divalent metal salts, ammonium salts and organic ammonium salts thereof.
3- (meth) allyloxypropylphosphonic acid, 4- (meth) allyloxybutylphosphonic acid, 5- (meth) allyloxypentylphosphonic acid, 6- (meth) allyloxyhexylphosphonic acid, 7- (meth) allyl Oxyheptylphosphonic acid, 8- (meth) allyloxyoctylphosphonic acid, 9- (meth) allyloxynonylphosphonic acid, 10- (meth) allyloxydecylphosphonic acid, 4- (meth) allyloxy-2-methylbutylphosphone Acids, 4- (meth) allyloxy-2-methylbutylphosphonic acid, and their monovalent, divalent, ammonium and organic ammonium salts.
3-vinyloxypropylphosphonic acid, 4-vinyloxybutylphosphonic acid, 5-vinyloxypentylphosphonic acid, 6-vinyloxyhexylphosphonic acid, 7-vinyloxyheptylphosphonic acid, 8-vinyloxyoctylphosphonic acid, 9- Vinyloxynonylphosphonic acid, 10-vinyloxydecylphosphonic acid, 4-vinyloxy-2-methylbutylphosphonic acid, 4-vinyloxy-2-methylbutylphosphonic acid, and monovalent metal salts, divalent metal salts thereof, Ammonium salts and organic ammonium salts.

In addition, other water-soluble monomers as described below may be copolymerized. Unsaturated amides such as (meth) acrylamide, (meth) acrylalkylamide, N-methylol (meth) acrylamide, N, N-dimethyl (meth) acrylamide; unsaturated cyanides such as (meth) acrylonitrile and α-chloroacrylonitrile Unsaturated esters such as vinyl acetate and vinyl propionate; aminoethyl (meth) acrylate, methylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, Unsaturated amines such as (meth) acrylic acid dibutylaminoethyl and vinylpyridine; Allyls such as (meth) allyl alcohol and glycidyl (meth) allyl ether; N-vinylsuccinimide, N-vinylcarbazole and 1-vinylimidazole , N-vinyl Caprolactam, N- vinyl oxazolidone, N- vinylpyrrolidone, N- vinylformamide, N- methyl -N- vinylformamide, N- vinylacetamide, N- vinyl compounds such as N- methyl -N- vinylacetamide;
Vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether.

The reaction point for introducing the structural unit (B) derived from the polyalkylene oxide chain and the structural unit (C) derived from the monomer having an anionic functional group into the lignin derivative is kraft lignin and / or a salt thereof. In addition to the phenolic hydroxy group, alcoholic hydroxy group, and thiol group contained in the above, a portion where a hydrogen radical is extracted and a radical is generated when a radical initiator is allowed to act is also included. A monomer having a polyalkylene oxide chain and a monomer having an anionic functional group that can be reacted after a radical initiator is caused to act on a kraft lignin include the radical polymerizable polyalkylene listed above. A monomer having an alkylene oxide chain and a monomer having an anionic functional group can be used.

Monomers having polyalkylene oxide chains and / or alkylene oxides and anionic functional groups that react with kraft lignin and / or its salts (or react in the presence of kraft lignin and / or its salts) The total use amount of the monomer should be 0.1 to 1000% by weight with respect to kraft lignin and / or a salt thereof. Preferably, it is 5 to 200% by weight, more preferably 10.0 to 100.0% by weight. When the total amount of monomers used is less than 0.1% by weight, the resulting lignin derivative is not sufficiently water-soluble, for example, when water is used as a dispersion medium, the dispersion performance may be inferior. . Conversely, when the total amount of monomers used exceeds 1000% by weight, the performance of the lignin skeleton, that is, the effect of improving dispersibility, and the effect of reducing the viscosity of concrete when used as a cement dispersant are manifested. There are things that do not.

Monomer and / or alkylene oxides (B) and anionic functional group having a polyalkylene oxide chain to be reacted with kraft lignin and / or a salt thereof (or reacted in the presence of kraft lignin and / or a salt thereof) The ratio of the used amount of the monomer (C) having a ratio of (B) / (C) must be 100/0 to 95/5 wt%. The proportion of the monomer (C) having an anionic functional group should be small, preferably 98/2 wt% or less, more preferably 99/1 wt% or less, and still more preferably 100/0 wt%. When the amount of the monomer (C) having an anionic functional group is larger than 95/5 wt% in the ratio (B) / (C), the dispersion performance as a dispersant is inferior.

For example, when alkylene oxide is reacted with kraft lignin and / or a salt thereof, a solvent may be used as necessary. When a solvent is used for this reaction, the solvent that can be used is not particularly limited. For example, water; alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol; benzene, toluene, xylene, cyclohexane, n -Aromatic or aliphatic hydrocarbons such as hexane; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; cyclic ethers such as tetrahydrofuran and dioxane; These solvents may be used alone or in combination of two or more.

Moreover, you may use a catalyst for the said reaction as needed. When a catalyst is used for the above reaction, either an acid catalyst or a base catalyst may be used. For example, sodium hydroxide or potassium hydroxide is suitable. The amount of the catalyst used is not particularly limited, but is preferably 0.001% by mass or more and 20% by mass or less, for example, based on the total mass of kraft lignin and / or a salt thereof and an alkylene oxide. More preferably, it is 0.01 mass% or more and 10 mass% or less.

The reaction temperature of the above reaction may be appropriately set according to the type of solvent used, and is not particularly limited, but is usually 0 ° C. or higher and 200 ° C. or lower. In particular, when a low-boiling compound such as ethylene oxide or propylene oxide is reacted, the reaction may be performed under pressure using an autoclave in order to improve the reaction rate.

When using a monomer having a radically polymerizable polyalkylene oxide chain and a monomer having an anionic functional group, the monomer component containing the monomer is graft-polymerized using a polymerization initiator. Just do it. Graft polymerization can be performed by methods such as solution polymerization and bulk polymerization. The solution polymerization can be performed either batchwise or continuously.

The solvent used for the graft polymerization is not particularly limited. For example, water; alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; aromatics such as benzene, toluene, xylene, cyclohexane, and n-hexane. Or, aliphatic hydrocarbons; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; cyclic ethers such as tetrahydrofuran and dioxane; These solvents may be used alone or in combination of two or more.

When maleic anhydride is used as the maleic monomer, aromatic or aliphatic hydrocarbons such as benzene, toluene, xylene, cyclohexane and n-hexane; acetic acid to avoid cleavage of the acid anhydride group; It is preferable to use an inert solvent such as esters such as ethyl; ketones such as acetone and methyl ethyl ketone. On the other hand, when maleic acid and / or a salt thereof is used as the maleic monomer, it is preferable to use at least one solvent selected from the group consisting of water and a lower alcohol having 1 to 4 carbon atoms. . In particular, it is more preferable to use water as a solvent in that the solvent removal step can be omitted.

When solution polymerization is performed using water as a solvent, a water-soluble polymerization initiator, for example, a persulfate such as ammonium persulfate, sodium persulfate, or potassium persulfate; hydrogen peroxide; 2 , 2′-azobis (2-methylpropionamidine) dihydrochloride and other cyclic azoamidine compounds such as 2,2′-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2 A water-soluble azo initiator such as an azonitrile compound such as carbamoylazoisobutyronitrile; These polymerization initiators may be used alone or in combination of two or more. The amount of the polymerization initiator used may be appropriately adjusted according to the type and amount of the monomer having a polyalkylene oxide chain and the monomer having an anionic functional group, and is not particularly limited. For example, it is preferably 0.01 mol% or more and 50 mol% or less, more preferably 1 mol% or more and 20 mol% or less with respect to the monomer used.

In this case, alkali metal sulfite such as sodium bisulfite, metabisulfite, sodium hypophosphite, Fe (II) salt such as molle salt, hydroxymethanesulfinate sodium dihydrate, hydroxylamine hydrochloride, thio Accelerators (reducing agents) such as urea, L-ascorbic acid or a salt thereof, erythorbic acid or a salt thereof may be used in combination. These accelerators (reducing agents) may be used alone or in combination of two or more. In particular, a combination of hydrogen peroxide and an organic reducing agent is preferable. As the organic reducing agent, L-ascorbic acid or a salt thereof, L-ascorbic acid ester, erythorbic acid or a salt thereof, erythorbic acid ester or the like is preferable. is there. The amount of the accelerator (reducing agent) used is not particularly limited. For example, it is preferably 0.1 mol% or more and 500 mol% or less, more preferably, relative to the polymerization initiator used. 1 mol% or more and 200 mol% or less, more preferably 10 mol% or more and 100 mol% or less.

When solution polymerization is performed using lower alcohols, aromatic or aliphatic hydrocarbons, esters or ketones as a solvent, or bulk polymerization is performed, benzoyl peroxide, lauroyl peroxide, sodium Peroxides such as peroxides; hydroperoxides such as t-butyl hydroperoxide and cumene hydroperoxide; azo compounds such as azobisisobutyronitrile; and the like are used as radical polymerization initiators. These radical polymerization initiators may be used alone or in combination of two or more. The amount of the radical polymerization initiator used may be appropriately adjusted according to the type and amount of the water-soluble monomer, and is not particularly limited. On the other hand, it is preferably 0.01 mol% or more and 50 mol% or less, more preferably 1 mol% or more and 20 mol% or less.

In this case, an accelerator such as an amine compound can be used in combination. Furthermore, when a mixed solvent of water and a lower alcohol is used, it can be appropriately selected from the radical polymerization initiator or a combination of the radical polymerization initiator and an accelerator. The amount of the accelerator used is not particularly limited. For example, it is preferably 0.1 mol% or more and 500 mol% or less, more preferably 1 mol%, based on the radical polymerization initiator used. As mentioned above, it is 200 mol% or less, More preferably, it is 10 mol% or more and 100 mol% or less.

The polymerization temperature of the graft polymerization may be appropriately set according to the type of solvent and polymerization initiator used, and is not particularly limited, but is preferably 0 ° C. or higher and 150 ° C. or lower, more preferably 30 ° C. The temperature is 120 ° C. or lower, more preferably 50 ° C. or higher and 100 ° C. or lower.

The method of charging each monomer into the reaction vessel is not particularly limited, a method in which the entire amount is initially charged into the reaction vessel at once, a method in which the entire amount is divided or continuously charged into the reaction vessel, and a part of the reaction vessel Any of the methods may be used, in which the initial amount is charged and the remainder is divided into reaction vessels or continuously charged. The radical polymerization initiator may be charged into the reaction vessel from the beginning, may be dropped into the reaction vessel, or may be combined according to the purpose.

In order to adjust the molecular weight of the obtained lignin derivative, a chain transfer agent may be used as necessary. When a chain transfer agent is used for the polymerization reaction, examples of usable chain transfer agents include thiols such as mercaptoethanol, thioglycerol, thioglycolic acid, 3-mercaptopropionic acid, thiomalic acid, and 2-mercaptoethanesulfonic acid. Chain transfer agents; secondary alcohols such as isopropyl alcohol; phosphorous acid, hypophosphorous acid and salts thereof (sodium hypophosphite, potassium hypophosphite, etc.), sulfurous acid, hydrogen sulfite, dithionite, meta Examples of conventionally known hydrophilic chain transfer agents include lower oxides of bisulfite and salts thereof (sodium sulfite, sodium hydrogen sulfite, sodium dithionite, sodium metabisulfite, and the like) and salts thereof. Furthermore, when a hydrophobic chain transfer agent is used, it is effective for improving the viscosity of the concrete composition when used as a cement dispersant. Hydrophobic chain transfer agents include 3 or more carbon atoms such as butanethiol, octanethiol, decanethiol, dodecanethiol, hexadecanethiol, octadecanethiol, cyclohexyl mercaptan, thiophenol, octyl thioglycolate, octyl 3-mercaptopropionate, etc. A thiol chain transfer agent having the following hydrocarbon group is preferred. These hydrophilic chain transfer agents and hydrophobic chain transfer agents may be used alone or in combination of two or more. Moreover, you may use combining a hydrophilic chain transfer agent and a hydrophobic chain transfer agent. Furthermore, in order to adjust the molecular weight, it is also effective to use a monomer having a high chain transfer property such as (meth) allylsulfonic acid and its salts. The amount of chain transfer agent used may be appropriately adjusted according to the type and amount of the water-soluble monomer, and is not particularly limited. For example, for the total water-soluble monomer used. , Preferably 0.1 mol% or more and 50 mol% or less, more preferably 1 mol% or more and 20 mol% or less.

In the graft polymerization, in order to obtain a graft polymer having a predetermined molecular weight with good reproducibility, it is necessary to allow the polymerization reaction to proceed stably. Therefore, in the case of solution polymerization, the dissolved oxygen concentration at 25 ° C. of the solvent used is preferably 5 ppm or less, more preferably 0.01 ppm or more and 4 ppm or less, further preferably 0.01 ppm or more and 2 ppm or less. Preferably it is 0.01 ppm or more and 1 ppm or less. When nitrogen substitution or the like is performed after the monomer is added to the solvent, the dissolved oxygen concentration of the system including the monomer is set to the above concentration.

The adjustment of the dissolved oxygen concentration of the solvent may be performed in a polymerization reaction tank, or a solution in which the amount of dissolved oxygen is adjusted in advance may be used. As a method for expelling oxygen in the solvent, for example, the following (1) The method of (5) is mentioned.

(1) After pressure-filling an inert gas such as nitrogen in a sealed container containing a solvent, the partial pressure of oxygen in the solvent is lowered by lowering the pressure in the sealed container. You may reduce the pressure in an airtight container under nitrogen stream.

(2) The liquid phase portion is vigorously stirred for a long time while the gas phase portion in the container containing the solvent is replaced with an inert gas such as nitrogen.

(3) An inert gas such as nitrogen is bubbled in the solvent in the container for a long time.

(4) The solvent is once boiled and then cooled in an inert gas atmosphere such as nitrogen.

(5) A static mixer (static mixer) is installed in the middle of the pipe, and an inert gas such as nitrogen is mixed in the pipe for transferring the solvent to the polymerization reaction tank.

When using the lignin derivative obtained by the graft polymerization, for example, as a cement dispersant, it is preferable to adjust to a pH of weak acid or higher in an aqueous solution state, more preferably pH 4 or higher, from the viewpoint of handleability. More preferably, the pH is 5 or more, and particularly preferably 6 or more. The pH can be adjusted using, for example, an alkaline substance such as inorganic salt such as hydroxide or carbonate of monovalent metal or divalent metal; ammonia; organic amine; These alkaline substances may be used alone or in combination of two or more. When pH needs to be lowered, especially when pH adjustment is required during polymerization, phosphoric acid, sulfuric acid, nitric acid, alkyl phosphoric acid, alkyl sulfuric acid, alkyl sulfonic acid, (alkyl) benzene sulfonic acid, etc. The pH can be adjusted using an acidic substance. These acidic substances may be used alone or in combination of two or more. Of these acidic substances, phosphoric acid is particularly preferred because it has a pH buffering action. Moreover, after completion | finish of reaction, a density | concentration adjustment can also be performed as needed.

In addition, in order to produce a lignin derivative, in the above method, a kraft lignin and / or a salt thereof is reacted with a monomer having a polyalkylene oxide chain and / or an alkylene oxide and a monomer having an anionic functional group. For kraft lignin and / or its salts chemically modified by methods such as alkylation, alkoxylation, sulfonation, sulfation, alkoxysulfation, sulfomethylation, aminomethylation, etc. A monomer having an alkylene oxide chain and / or a monomer having an alkylene oxide and an anionic functional group may be reacted, and a monomer having a polyalkylene oxide chain in kraft lignin and / or a salt thereof, and And / or a single molecule having an alkylene oxide and an anionic functional group After reacting the body may be subjected to the chemical modification. Further, after reacting the water-soluble monomer, crosslinking may be performed using formaldehyde or a polyfunctional crosslinking agent.

<Antifoaming agent>
Conventionally known additives may be blended with the dispersant of the present invention as long as the dispersion performance is not impaired. Specific examples of conventionally known additives include antifoaming agents, air entraining agents, wetting agents, waterproofing agents, viscosity modifiers and the like. These additives may be used alone or in combination of two or more.

Hereinafter, the antifoaming agent which is a typical additive will be described.

When an antifoaming agent is added to the dispersant of the present invention, the antifoaming agent may be added after the lignin derivative is produced, or before the kraft lignin and / or salt thereof and the water-soluble monomer are reacted. Alternatively, it may be added during the reaction. Examples of usable antifoaming agents include polyoxyalkylenes such as (poly) oxyethylene (poly) oxypropylene adducts; diethylene glycol heptyl ether, polyoxyethylene oleyl ether, polyoxypropylene butyl ether, polyoxyethylene polyoxy Polyoxyalkylene alkyl ethers such as propylene 2-ethylhexyl ether and oxyethyleneoxypropylene adducts to higher alcohols having 12 to 14 carbon atoms; polyoxyalkylenes such as polyoxypropylene phenyl ether and polyoxyethylene nonylphenyl ether ( Alkyl) aryl ethers; 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 3-methyl Acetylene ethers obtained by addition polymerization of alkylene oxide to acetylene alcohol such as ru-1-butyn-3-ol; (poly) oxyalkylene fatty acid esters such as diethylene glycol oleate, diethylene glycol laurate, ethylene glycol distearate Polyoxyalkylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate and polyoxyethylene sorbitan trioleate; polyoxyalkylene alkyls such as sodium polyoxypropylene methyl ether sulfate and sodium polyoxyethylene dodecyl phenyl ether sulfate ( Aryl) ether sulfates; polyoxyethylene stearyl phosphates and other poly Xyloxyalkylene alkyl phosphates; polyoxypropylene polyoxyethylene laurylamine (1-20 mol addition of propylene oxide, 1-20 mol addition product of ethylene oxide, etc.), cured beef tallow amine added with alkylene oxide (1-20 propylene oxide) Polyoxyalkylene alkylamines such as a mole addition, an ethylene oxide 1-20 mole adduct, and the like; a polyoxyalkylene amide; and the like. These antifoaming agents may be used alone or in combination of two or more.

The blending amount of the antifoaming agent is preferably 0.0001% by mass or more and 10% by mass or less, more preferably 0.001% by mass or more and 8% by mass or less with respect to the mass of the lignin derivative. If the blending amount of the antifoaming agent is less than 0.0001% by mass, the defoaming effect may not be sufficiently exhibited. On the contrary, if the blending amount of the antifoaming agent exceeds 20% by mass, the effect of defoaming is substantially saturated, and the defoaming agent is used more than necessary, which increases the production cost. There is.

<To be dispersed>
The dispersion to be dispersed using the dispersant of the present invention is not particularly limited, and examples thereof include various organic substances and inorganic substances. The shape of the dispersion target is not particularly limited, and examples thereof include powder, particles, granules, fibers, and flat plates.

Specific examples of the organic substance include, for example, phospho yellow, disazo yellow, disazo orange, naphthol red, copper phthalocyanine pigment, phosphomolybdenum tungstate, tannate, katanol, tamol lake, isoindolinone ero greenish, iso Organic pigments such as indolineine ethoredish, quinacridone, dioxazine violet, perinone orange, perylene vermilion, perylene cullet, perylene red, perylene maroon; synthesis of polycarbonate, polyvinyl chloride, polymethyl methacrylate, fluororesin, etc. Resin: Aluminum stearate, zinc stearate, calcium stearate, magnesium stearate, zinc stearate / calcium stearate composite, stearic acid , Cadmium stearate, barium stearate, calcium laurate, and metal soaps such as zinc laurate and the like. These organic substances generally have an average particle size of 100 μm or less, preferably 0.1 μm or more and 50 μm or less. These organic substances may be used alone or in combination of two or more.

Specific examples of inorganic substances include, for example, silicates such as kaolin, aluminum silicate, clay, talc, mica, calcium silicate, sericite, bentonite; calcium carbonate, magnesium carbonate, barium carbonate, basic lead carbonate, etc. Carbonates; sulfates such as calcium sulfate and barium sulfate; chromates such as strontium chromate and pigment yellow; molybdates such as zinc molybdate, calcium molybdate and magnesium molybdate; alumina, antimony oxide, titanium oxide, Metal oxides such as cobalt oxide, ferric tetroxide, ferric trioxide, trilead tetroxide, lead monoxide, chromium oxide green, tungsten trioxide, yttrium oxide; aluminum hydroxide, magnesium hydroxide, calcium hydroxide, Iron hydroxide, metatitanium Metal hydroxides such as silicon carbide, tungsten carbide, boron carbide, titanium carbide, etc .; aluminum nitride, silicon nitride, boron nitride, zirconia, barium titanate, satin white, carbon black, graphite, chrome yellow, sulfide Examples include mercury, ultramarine, Paris blue, titanium yellow, chrome vermilion, lithopone, copper acetoarsenite, nickel, silver, palladium, and lead zirconate titanate. These inorganic substances generally have an average particle size of 100 μm or less, preferably 0.1 μm or more and 50 μm or less. These inorganic substances may be used alone or in combination of two or more.

The dispersion medium for dispersing the organic substance and / or inorganic substance using the dispersant of the present invention is not particularly limited, and examples thereof include water; fuel oils such as kerosene, light oil, and kerosene; hexane Aliphatic hydrocarbons such as benzene, toluene, xylene and cresol; alcohols such as ethanol, methanol, isopropyl alcohol, butyl alcohol and pentyl alcohol; acetic acid Esters such as ethyl and dioctyl phthalate; ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, ethylene glycol mono Ethers such as chill ether, carbitol, monoglyme, diglyme, tetraglyme, methyl cellosolve, butyl cellosolve; diols such as butanediol, pentanediol, hexanediol; 1,1,1-trichloroethane, trichloroethylene, dichloroethylene, chloro Halogenated hydrocarbons such as difluoromethane; ketones such as methyl isoamyl ketone, methyl isobutyl ketone, acetone and methyl ethyl ketone; terpineol, liquid paraffin, mineral spirit, N- (2-hydroxyethyl) pyrrolidone, glycerin and the like. Of these dispersion media, water is particularly preferred. These dispersion media may be used alone or in combination of two or more.

When using the dispersing agent of this invention, the method of mixing with a dispersion medium is not specifically limited. For example, the dispersant may be added after mixing the dispersant of the present invention with a dispersion medium, or the dispersant of the present invention may be added to the dispersion medium simultaneously or sequentially. Alternatively, the dispersant of the present invention may be added later after the dispersion medium is mixed with the dispersion medium in advance.

The amount of the dispersing agent of the present invention may be appropriately adjusted according to the type and amount of the dispersion, and is not particularly limited. For example, preferably, for 100 parts by mass of the dispersion It is 0.01 mass part or more and 10 mass parts or less, More preferably, it is 0.1 mass part or more and 5 mass parts or less. The dispersion medium is usually used in an amount of 20 to 1,000 parts by mass with respect to 100 parts by mass of the dispersion.

≪Cement dispersant≫
The dispersant of the present invention can be used for various applications, but is particularly suitable as a cement dispersant. Therefore, the case where the dispersant of the present invention is used as a cement dispersant will be described in detail below.

When the dispersant of the present invention is used as a cement dispersant, it may be used in the form of an aqueous solution, or it may be neutralized with a divalent metal hydroxide such as calcium or magnesium after the reaction to obtain a polyvalent metal. It is dried after being made into salt, supported on inorganic powder such as silica-based fine powder, and dried in a thin film form on a support using a drum-type drying device, a disk-type drying device or a belt-type drying device. After solidifying, it may be pulverized or dried and solidified by a spray dryer to be used as a powder. Alternatively, the powdered dispersant of the present invention may be blended in advance with a water-free cement composition such as cement powder or dry mortar and used as a premix product for plastering, floor finishing, grout, etc. It may be added at the time of kneading the cement composition.

The dispersant of the present invention is useful as a cement dispersant, and can be used for various hydraulic materials, that is, cement compositions such as cement and gypsum and other hydraulic materials. Specific examples of a hydraulic composition containing such a hydraulic material, water, and the cement dispersant of the present invention, and further containing fine aggregate (such as sand) and coarse aggregate (such as crushed stone) as necessary. Examples thereof include cement paste, mortar, concrete, and plaster.

Among the hydraulic compositions, a cement composition that uses cement as the hydraulic material is the most common, and the cement composition contains the dispersant of the present invention, cement, and water as essential components. Such a cement composition is one of the preferred embodiments of the present invention.

The cement used in the cement composition is not particularly limited, and specific examples include, for example, Portland cement (ordinary, early strength, very early strength, moderate heat, sulfate resistance, and respective low alkalis). ), Various mixed cements (blast furnace cement, silica cement, fly ash cement), white Portland cement, alumina cement, super fast cement (1 clinker fast cement, 2 clinker fast cement, magnesium phosphate cement), grout cement , Oil well cement, low exothermic cement (low exothermic blast furnace cement, fly ash mixed low exothermic blast furnace cement, high content belite cement), ultra high strength cement, cement-based solidified material, eco-cement (city waste incineration ash, sewage sludge) Cement produced from one or more types of incinerated ash) And the like. Furthermore, fine powder such as blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, limestone powder, or gypsum may be added to the cement composition. Aggregates include gravel, crushed stone, granulated slag, recycled aggregate, etc., as well as silica, clay, zircon, high alumina, silicon carbide, graphite, chrome, chromia, magnesia Refractory aggregates such as can be used.

In the above cement composition, unit water per Part 1 m ^3, the cement usage and water / cement ratio (mass ratio), unit water is preferably 100 kg / ^{m 3} or more, 185 kg / ^{m 3} or less, more preferably 120kg / M ³ or more and 175 kg / m ³ or less, and the amount of cement used is preferably 200 kg / m ³ or more and 800 kg / m ³ or less, more preferably 250 kg / m ³ or more and 800 kg / m ³ or less, The cement ratio (mass ratio) is preferably 0.1 or more and 0.7 or less, more preferably 0.2 or more and 0.65 or less, and it can be used widely from poor blending to rich blending. The dispersant of the present invention has a high water reduction rate region, that is, a water / cement ratio such as a water / cement ratio (mass ratio) of 0.15 or more and 0.5 or less (preferably 0.15 or more and 0.4 or less). Can be used even in a low region, and is effective for both high-strength concrete having a large unit cement amount and a small water / cement ratio, and poor-mixed concrete having a unit cement amount of 300 kg / m ³ or less.

In the above cement composition, the amount of the dispersant of the present invention is preferably set to 0. 0 relative to the cement mass in terms of solid content when used for mortar, concrete, or the like using hydraulic cement. 01% by mass or more and 10.0% by mass or less, more preferably 0.02% by mass or more and 5.0% by mass or less, further preferably 0.05% by mass or more and 3.0% by mass or less, particularly preferably 0%. It is 1 mass% or more and 2.0 mass% or less. Such a blending amount brings various preferable effects such as a reduction in unit water amount, an increase in strength, and an improvement in durability. When the blending amount of the dispersant of the present invention is less than 0.01% by mass, the dispersion performance may not be fully exhibited. On the contrary, when the blending amount of the dispersant of the present invention exceeds 10.0% by mass, the effect of improving the dispersibility is substantially saturated, and the dispersant of the present invention is used more than necessary. Therefore, the manufacturing cost may increase.

The cement composition has high dispersibility and dispersion retention performance even in a high water reduction rate region, and exhibits sufficient initial dispersibility and viscosity reduction even at low temperatures, and has excellent workability. To ready mixed concrete, concrete for concrete secondary products (precast concrete), concrete for centrifugal molding, concrete for vibration compaction, steam-cured concrete, shotcrete, etc. Is required to have high fluidity such as high-fluidity concrete (slump value of 25 cm or more, slump flow value of 50 cm or more and 70 cm or less), self-filling concrete, self-leveling material, etc. Mortar or concrete It is also effective.

Furthermore, conventionally known cement dispersants can be used in combination with the cement dispersant of the present invention. For example, the following can be used.

Lignin sulfonate; polyol derivative; naphthalene sulfonic acid formalin condensate; melamine sulfonic acid formalin condensate; polystyrene sulfonate; aminoaryl sulfonic acid-phenol-formaldehyde condensate as described in JP-A-1-113419 As a component (a) as described in JP-A-7-267705, co-polymerization of a polyalkylene glycol mono (meth) acrylic acid ester compound and a (meth) acrylic acid compound A copolymer and / or a salt thereof, and as a component (b), a copolymer of a polyalkylene glycol mono (meth) allyl ether compound and maleic anhydride and / or a hydrolyzate thereof, and / or a salt thereof, (C) As a component, polyalkylene glycol A cement dispersant containing a copolymer of a (meth) allyl ether compound and a maleic ester of a polyalkylene glycol compound and / or a salt thereof; as component A as described in Japanese Patent No. 2508113, Copolymer of (meth) acrylic acid polyalkylene glycol ester and (meth) acrylic acid (salt), B component as a specific polyethylene glycol polypropylene glycol compound, C component as a specific surfactant Admixture; polyethylene (propylene) glycol ester of (meth) acrylic acid or polyethylene (propylene) glycol mono (meth) allyl ether, (meth) allylsulfonic acid (salt) as described in JP-A-62-216950 ), And (meth) acrylic A copolymer comprising (salt); polyethylene (propylene) glycol ester of (meth) acrylic acid, (meth) allylsulfonic acid (salt), and (meth) as described in JP-A-1-226757 Copolymer comprising acrylic acid (salt); polyethylene (propylene) glycol ester of (meth) acrylic acid, (meth) allylsulfonic acid (salt) or p- (as described in JP-B-5-36377 A copolymer comprising (meth) allyloxybenzenesulfonic acid (salt) and (meth) acrylic acid (salt); polyethylene glycol mono (meth) allyl ether and malein as described in JP-A-4-149056 Copolymer with acid (salt); polyethylene glycol of (meth) acrylic acid as described in JP-A-5-170501 Recall ester, (meth) allylsulfonic acid (salt), (meth) acrylic acid (salt), alkanediol mono (meth) acrylate, polyalkylene glycol mono (meth) acrylate, and α having an amide group in the molecule Copolymers comprising β-unsaturated monomers; polyethylene glycol mono (meth) allyl ether, polyethylene glycol mono (meth) acrylate, (meth) acrylic acid alkyl ester as described in JP-A-6-191918 , (Meth) acrylic acid (salt), and a copolymer comprising (meth) allylsulfonic acid (salt) or p- (meth) allyloxybenzenesulfonic acid (salt); described in JP-A-5-43288 Such as alkoxypolyalkylene glycol monoallyl ether and maleic anhydride Copolymer, or a hydrolyzate thereof, or a salt thereof; as described in JP-B-58-38380, can be copolymerized with polyethylene glycol monoallyl ether, maleic acid, and monomers thereof. Copolymer consisting of various monomers, salts thereof, or esters thereof; polyalkylene glycol mono (meth) acrylate ester monomers as described in JP-B-59-18338; ) A copolymer comprising acrylic acid monomers and monomers copolymerizable with these monomers; having a sulfonic acid group as described in JP-A-62-1119147 (meta) ) A copolymer comprising an acrylate ester and, if necessary, a monomer copolymerizable therewith, or a salt thereof; alkoxy as described in JP-A-6-271347 Esterification reaction product of copolymer of realkylene glycol monoallyl ether and maleic anhydride and polyoxyalkylene derivative having an alkenyl group at the terminal; alkoxy polyalkylene as described in JP-A-6-298555 Esterification reaction product of a copolymer of glycol monoallyl ether and maleic anhydride and a polyoxyalkylene derivative having a hydroxy group at the terminal; 3-methyl-, as described in JP-A-62-68806 An alkenyl ether monomer obtained by adding ethylene oxide or the like to a specific unsaturated alcohol such as 3-buten-1-ol, an unsaturated carboxylic acid monomer, and a monomer copolymerizable with these monomers Or a polycarboxylic acid (salt) such as a salt thereof. These conventionally known cement dispersants may be used alone or in combination of two or more.

The dispersant of the present invention can be used in combination with an oxycarboxylic acid-based compound in addition to the conventionally known cement dispersant. By containing the oxycarboxylic acid-based compound, higher dispersion retention performance can be exhibited even in a high-temperature environment. As the oxycarboxylic acid compound, an oxycarboxylic acid having 4 to 10 carbon atoms or a salt thereof is preferable, and specifically, for example, gluconic acid, glucoheptonic acid, alabonic acid, malic acid, citric acid, and sodium thereof. Inorganic salts or organic salts such as potassium, calcium, magnesium, ammonium, triethanolamine, and the like. These oxycarboxylic acid compounds may be used alone or in combination of two or more. Of these oxycarboxylic acid compounds, gluconic acid or a salt thereof is particularly suitable. In particular, in the case of poor blended concrete, a lignin sulfonate-based dispersant is used as a sulfonic acid-based dispersant having a sulfonic acid group in the molecule, and gluconic acid or a salt thereof is used as an oxycarboxylic acid-based compound. It is preferable.

When the dispersant of the present invention and a conventionally known cement dispersant are used in combination, the blending ratio of the dispersant of the present invention and the conventionally known cement dispersant (that is, the dispersant of the present invention in terms of solid content / the conventionally known cement dispersant). The cement dispersant: mass ratio) is preferably 1 to 99/99 to 1, more preferably 5 to 95/95 to 5, still more preferably 10 to 90/90 to 10, particularly preferably 20 to 80/80 to. 20. When the dispersant of the present invention and the oxycarboxylic acid compound are used in combination, the blending ratio of the dispersant of the present invention and the oxycarboxylic acid compound (that is, the dispersant / oxycarboxylic acid of the present invention in terms of solid content) System compound: mass ratio) is preferably 1 to 99/99 to 1, more preferably 5 to 95/95 to 5, still more preferably 10 to 90/90 to 10, particularly preferably 20 to 80/80 to 20. It is. Further, when the dispersant of the present invention, the conventionally known cement dispersant and the oxycarboxylic acid compound are used in combination, the mixing ratio of the dispersant of the present invention, the conventionally known cement dispersant and the oxycarboxylic acid compound ( That is, the dispersant of the present invention / conventionally known cement dispersant / oxycarboxylic acid compound: mass ratio) in terms of solid content is preferably 1 to 98/1 to 98/1 to 98, more preferably 5 to 90. / 5 to 90/5 to 90, more preferably 10 to 90/5 to 85/5 to 85, and particularly preferably 20 to 80/10 to 70/10 to 70.

Moreover, the said cement composition can contain the other conventionally well-known cement additive (material) which is illustrated to following (1)-(11).

(1) Water-soluble polymer substance: unsaturated carboxylic acid polymer such as polyacrylic acid (sodium), polymethacrylic acid (sodium), polymaleic acid (sodium), sodium salt of acrylic acid / maleic acid copolymer; methylcellulose Nonionic cellulose ethers such as ethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, hydroxypropyl cellulose; alkylated or hydroxyalkylated derivatives of polysaccharides such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose A part or all of the hydrogen atoms of the hydroxy group have a hydrophobic substituent having a hydrocarbon chain having 8 to 40 carbon atoms as a partial structure; Polysaccharide derivatives substituted with an ionic hydrophilic substituent having a phonic acid group or a salt thereof as a partial structure; yeast glucan, xanthan gum, β-1.3 glucans (both linear and branched) , For example, polysaccharides produced by microbial fermentation such as curdlan, paramylon, pachyman, scleroglucan, laminaran); polyacrylamide; polyvinyl alcohol; starch; starch phosphate; sodium alginate; gelatin; A copolymer of acrylic acid having an amino group therein and its quaternary compound.

(2) Polymer emulsion: Copolymers of various vinyl monomers such as alkyl (meth) acrylate.

(3) Curing retarders other than oxycarboxylic acid compounds: monosaccharides such as glucose, fructose, galactose, saccharose, xylose, apiose, ribose, isomerized sugar, oligosaccharides such as disaccharide and trisaccharide, or dextrin Oligosaccharides or polysaccharides such as dextran, sugars such as molasses containing them; sugar alcohols such as sorbitol; magnesium fluorosilicate; phosphoric acid and its salts or boric acid esters; aminocarboxylic acid and its salts; Protein; Humic acid; Tannic acid; Phenol; Polyhydric alcohol such as glycerol; Aminotri (methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephos Phosphate) and alkali metal salts thereof, such as phosphonic acid and derivatives thereof such as alkaline earth metal salts.

(4) Early strengthening agents / accelerators: soluble calcium salts such as calcium chloride, calcium nitrite, calcium nitrate, calcium bromide and calcium iodide; chlorides such as iron chloride and magnesium chloride; sulfates; potassium hydroxide; Sodium hydroxide; carbonate; thiosulfate; formate such as formic acid and calcium formate; alkanolamine; alumina cement; calcium aluminate silicate.

(5) Antifoaming agents other than oxyalkylene-based: mineral oil-based antifoaming agents such as coconut oil and liquid paraffin; fat and oil-based antifoaming agents such as animal and vegetable oils, sesame oil, castor oil, and these alkylene oxide adducts; oleic acid and stearic acid Fatty acid-based antifoaming agents such as these alkylene oxide adducts; Fatty acid ester-based antifoaming agents such as glycerin monoricinoleate, alkenyl succinic acid derivatives, sorbitol monolaurate, sorbitol trioleate, natural wax; octyl alcohol, hexadecyl Alcohol defoamers such as alcohol, acetylene alcohol and glycols; Amide defoamers such as acrylate polyamines; Phosphate ester defoamers such as tributyl phosphate and sodium octyl phosphate; Aluminum stearate, calcium oleate, etc. Metal soap base defoaming agents; dimethylsilicone oils, silicone pastes, silicone emulsions, organic modified polysiloxanes (polyorganosiloxanes such as dimethylpolysiloxane), and silicone-based antifoaming agent such as fluorosilicone oils.

(6) AE agent: resin soap, saturated or unsaturated fatty acid, sodium hydroxystearate, lauryl sulfate, ABS (alkyl benzene sulfonic acid), LAS (linear alkyl benzene sulfonic acid), alkane sulfonate, polyoxyethylene alkyl (phenyl) ether , Polyoxyethylene alkyl (phenyl) ether sulfate or a salt thereof, polyoxyethylene alkyl (phenyl) ether phosphate or a salt thereof, protein material, alkenyl sulfosuccinic acid, α-olefin sulfonate, and the like.

(7) Other surfactants: aliphatic monohydric alcohols having 6 to 30 carbon atoms in the molecule such as octadecyl alcohol and stearyl alcohol, and those having 6 to 30 carbon atoms in the molecule such as abiethyl alcohol Intramolecular such as alicyclic monohydric alcohol, monodecyl mercaptan having 6 to 30 carbon atoms in the molecule such as dodecyl mercaptan, etc. Intramolecular such as alkylphenol having 6 to 30 carbon atoms in the molecule such as nonylphenol, dodecylamine 10 mol or more of an alkylene oxide such as ethylene oxide and propylene oxide was added to a carboxylic acid having 6 to 30 carbon atoms in the molecule such as an amine having 6 to 30 carbon atoms, lauric acid or stearic acid. Polyalkylene oxide derivatives; alkyl or alkoxy groups Alkyl diphenyl ether sulfonates, which may have as a group, two phenyl groups having a sulfone group ether-bonded; various anionic surfactants; various cationic surfactants such as alkylamine acetate and alkyltrimethylammonium chloride Agents; various nonionic surfactants; various amphoteric surfactants;

(8) Waterproofing agent: fatty acid (salt), fatty acid ester, fats and oils, silicone, paraffin, asphalt, wax and the like.

(9) Rust preventive: nitrite, phosphate, zinc oxide and the like.

(10) Crack reducing agent: polyoxyalkyl ether and the like.

(11) Expansion material: Ettlingite, coal, etc.

Other conventionally known cement additives (materials) include cement wetting agents, thickeners, separation reducing agents, flocculants, drying shrinkage reducing agents, strength enhancers, self-leveling agents, rust preventives, colorants, anti-corrosion agents. Examples include mold agents. These conventionally known cement additives (materials) may be used alone or in combination of two or more.

In the cement composition, the following (1) to (4) may be mentioned as particularly preferred embodiments for components other than cement and water.

(1) A combination comprising two components of the dispersant of the present invention and an oxyalkylene antifoaming agent. Examples of the oxyalkylene antifoaming agent include polyoxyalkylenes, polyoxyalkylene alkyl ethers, polyoxyalkylene acetylene ethers, polyoxyalkylene alkylamines and the like. These oxyalkylene antifoaming agents may be used alone or in combination of two or more. Of these oxyalkylene antifoaming agents, polyoxyalkylene alkylamines are particularly preferred. The amount of the oxyalkylene antifoaming agent is preferably 0.01% by mass or more and 20% by mass or less with respect to the mass of the lignin derivative contained in the dispersant of the present invention.

(2) A combination comprising two components of the dispersant of the present invention and a material separation reducing agent as essential. Examples of the material separation reducing agent include various thickeners such as nonionic cellulose ethers, a hydrophobic substituent composed of a hydrocarbon chain having 4 to 30 carbon atoms as a partial structure, and an alkylene having 2 to 18 carbon atoms. Examples thereof include compounds having a polyoxyalkylene chain in which an oxide is added in an average addition mole number of 2 to 300. These material separation reducing agents may be used alone or in combination of two or more. The blending mass ratio of the dispersant of the present invention to the material separation reducing agent is preferably 10/90 to 99.99 / 0.01, more preferably 50/50 to 99.9 / 0.1. The cement composition of this combination is suitable as a high fluidity concrete, a self-filling concrete, and a self-leveling material.

(3) A combination comprising two components of the dispersant of the present invention and an accelerator as essential. Examples of the accelerator include soluble calcium salts such as calcium chloride, calcium nitrite, and calcium nitrate; chlorides such as iron chloride and magnesium chloride; thiosulfate; formate salts such as formic acid and calcium formate; . These accelerators may be used alone or in combination of two or more. The blending mass ratio of the dispersant and the accelerator of the present invention is preferably 10/90 to 99.9 / 0.1, more preferably 20/80 to 99/1.

(4) A combination comprising essentially three components of the dispersant of the present invention, an oxyalkylene antifoaming agent and an AE agent. Examples of the oxyalkylene antifoaming agent include polyoxyalkylenes, polyoxyalkylene alkyl ethers, polyoxyalkylene acetylene ethers, polyoxyalkylene alkylamines and the like. These oxyalkylene antifoaming agents may be used alone or in combination of two or more. Of these oxyalkylene antifoaming agents, polyoxyalkylene alkylamines are particularly preferred. The blending amount of the oxyalkylene antifoaming agent is preferably 0.01% by mass or more and 20% by mass or less with respect to the mass of the lignin derivative contained in the dispersant of the present invention. On the other hand, the blending amount of the AE agent is preferably 0.001% by mass or more and 2% by mass or less with respect to the mass of the cement.

The dispersant of the present invention can exhibit high dispersion performance as compared with conventional dispersants such as lignin sulfonic acid. Therefore, for example, when used as a cement dispersant, the viscosity of kneaded mortar or concrete is lowered, and workability can be improved. The novel lignin derivative of the present invention can similarly exhibit high dispersion performance, for example, dispersant, chelating agent, cleaning agent, flocculant, thickener, coating agent, paint, adhesive, water-absorbing resin. It can be used widely.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, but may be appropriately modified within a range that can meet the purpose described above and below. It is also possible to implement, and they are all included in the technical scope of the present invention. Unless otherwise specified, “part” means “part by weight” and “%” means “mass%”.

The molecular weight of the lignin derivative was measured in Example 1 and Comparative Example 1 using the following measurement conditions.

<Measurement conditions (b)>
Column used: manufactured by Tosoh Corporation, TSK guard column α, TSKgel α-5000, α-4000, and α-3000 connected in this order;
Eluent: A solution prepared by dissolving 44.5 g of boric acid in a solution of 1,800 g of acetonitrile and 7141.1 g of water and adjusting the pH to 10.0 with 30% aqueous NaOH solution was used;
Sample injection amount: 100 μL;
Flow rate: 1.0 mL / min;
Column temperature: 40 ° C .;
Detector: manufactured by Japan Waters, 2414 differential refraction detector;
Analysis software: Empower2 Software, manufactured by Waters, Japan;
Calibration curve standard material: polyethylene glycol [peak top molecular weight (Mp) 300
, 200,000, 101,000, 50,000, 27,700, 11,840, 6,450, 4,020, 1,010, 400];
Calibration curve: Created by cubic equation based on Mp value and elution time of polyethylene glycol;
A sample prepared by dissolving a polymer (aqueous solution) with the eluent so that the polymer concentration was 0.5% by mass was used.

Example 1
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introducing tube and a reflux cooling device, 30.0 g of water, 6.67 g of Kraft lignin (manufactured by Aldrich, product number 471003), and methoxypolyethylene glycol # 1000 3.35 g of methacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., M-230G) was charged, the inside of the reaction apparatus was purged with nitrogen under stirring, and heated to 80 ° C. under a nitrogen atmosphere. After the liquid temperature reached 80 ° C., 0.667 g of 2,2′-azobis (2-methylpropionamidine) dihydrochloride (manufactured by Wako Pure Chemical Industries, V-50, product number 017-21332) was added to 9.33 g of water. The aqueous solution dissolved in was added and allowed to stand at 80 ° C. for 4 hours to complete the polymerization reaction. As a new ligurin derivative (1) of the present invention, a mass average molecular weight of 34,000 was obtained.

≪Comparative example 1≫
A glass reactor equipped with a thermometer, a stirrer, a dripping device, a nitrogen introducing tube and a reflux cooling device, 29.7 g of water, 6.67 g of kraft lignin (manufactured by Aldrich, product number 471003), methoxypolyethylene glycol # 1000 methacrylate (Manufactured by Shin-Nakamura Chemical Co., Ltd., M-230G) 3.08 g, 0.209 g of acrylic acid and 0.390 g of 30% aqueous sodium hydroxide solution were charged, and the inside of the reactor was purged with nitrogen under stirring. Heated. After the liquid temperature reached 80 ° C., 0.667 g of 2,2′-azobis (2-methylpropionamidine) dihydrochloride (manufactured by Wako Pure Chemical Industries, V-50, product number 017-21332) was added to 9.33 g of water. The aqueous solution dissolved in was added and allowed to stand at 80 ° C. for 4 hours to complete the polymerization reaction. A mass average molecular weight of 33,700 was obtained as a comparative product (1) of the ligurin derivative of the present invention.

<< Test Example 1 >>
<Mortar blending and kneading method>
The mortar kneading was performed as follows.

In a Hobart mortar mixer (model number N-50, manufactured by Hobart), 450 g of ordinary Portland cement manufactured by Taiheiyo Cement Co., Ltd. was added. 13.5 g of a 1% aqueous solution of the name “MA404” is weighed and diluted with water, and 225 g is added at low speed. After charging, knead at low speed for 30 seconds, and then add 1,350 g of standard sand for cement strength test (as defined in 5.1.3 of JIS R 5201-1997 Annex 2) at low speed for 30 seconds and rotate at high speed. And kneading for 30 seconds to stop the rotation. After 1 minute and 30 seconds, the mixture is scraped off and allowed to stand, and then kneaded at a high speed for 1 minute. Six minutes after the start, the flow cone (described in JIS R 5201-1997) was filled with mortar that had been kneaded in two layers, the cone was pulled up, and immediately, 15 drops were given to the mortar for 15 seconds. The flow was measured and this was taken as the 15-stroke flow value. The flow was measured according to JIS R 5201-1997. In addition, the value of the flow indicates that the greater the numerical value, the higher the dispersibility. The results of the mortar test are shown in Table 1.

As is apparent from Table 1, when the lignin derivative (1) of the present invention is compared with the lignin derivative comparative product (1), the mortar flow of the novel ligrin derivative (1) of the present invention at the same addition amount. The value is large. That is, it can be seen that the novel lignin derivative (1) of the present invention is superior in dispersion performance for cement.

The dispersant of the present invention can exhibit high dispersion performance as compared with conventional dispersants such as lignin sulfonic acid. Therefore, the dispersant of the present invention is useful for dispersing various dispersions. The novel lignin derivative of the present invention can similarly exhibit high dispersion performance, for example, dispersant, chelating agent, cleaning agent, flocculant, thickener, coating agent, paint, adhesive, water-absorbing resin. It can be used widely.

Claims (3)

A structural unit derived from kraft lignin and / or a salt thereof (A), a structural unit derived from a polyalkylene oxide chain (B), and a structural unit derived from a monomer having an anionic functional group (C); / {(B) + (C)} has a ratio of 100 / 0.1 to 100/1000 wt% and (B) / (C) has a ratio of 100/0 to 95/5 wt%,
The structural unit (B) derived from the polyalkylene oxide chain is an alkyl obtained by adding 1 to 500 mol of an alkylene oxide having 2 to 18 carbon atoms to an alcohol having 1 to 30 carbon atoms or an amine having 1 to 30 carbon atoms. Diesters of (poly) alkylene glycols and unsaturated dicarboxylic acids; diesters of unsaturated dicarboxylic acids and glycols having 2 to 18 carbon atoms or polyalkylene glycols having 2 to 500 addition moles of these glycols; Esters of alkoxy (poly) alkylene glycols obtained by adding 1 to 500 moles of an alkylene oxide having 2 to 18 carbon atoms to an alcohol having 1 to 30 carbon atoms and unsaturated monocarboxylic acids; to unsaturated monocarboxylic acids 1 to 500 moles of adducts of alkylene oxides of 2 to 18 carbon atoms; Dispersing agent characterized by containing the lignin derivative is a structural unit formed by any of the alkylene oxide addition compounds of the unsaturated alcohol obtained by 2-300 mols of alkylene oxide to the sum alcohol. The dispersant, dispersing agent according to claim 1 which is a cement dispersing agent. A method for producing the dispersant according to claim 1 or 2, wherein the production method comprises:
A step of obtaining a lignin derivative contained in a dispersant by reacting kraft lignin and / or a salt thereof with a monomer having a polyalkylene oxide chain and / or an alkylene oxide, and a monomer having an anionic functional group. The manufacturing method of the dispersing agent characterized by including.