JP2018035012A - Additive for cement and cement composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an additive for cement capable of remarkably improving a strength of a cured product of a cement composition for a long period of time, and to provide a cement composition capable of remarkably improving a strength of the cured product over a long period of time.SOLUTION: An additive for cement contains at least one (component A) selected from polyethylene glycol (component a1) having a weight average molecular weight of 150,000 or more and a component (component a2) having such a structure that alkylene oxide is added to a tri- or higher polyhydric alcohol, and at least one (component B) selected from an oxycarboxylic acid or its salt, a keto acid or its salt, sugar and sugar alcohol.SELECTED DRAWING: None

Description

  The present invention relates to a cement additive and a cement composition.

  Cement compositions such as mortar and concrete generally include cement, aggregate, and water, and preferably further include a cement admixture to increase fluidity and reduce water.

  Recently, there has been an increasing demand for cement compositions to improve the strength performance of cured products in addition to the improvement of water reduction performance. For example, depending on the use of the cement composition, early strength development is desired, and various studies have been made (for example, Patent Document 1).

  On the other hand, depending on the use of the cement composition, an improvement in the strength of the cured product of the cement composition over a long period of time (for example, an improvement in strength at the 4-week level) has been required.

JP 2011-84459 A

  The subject of this invention is providing the additive for cement which can improve the intensity | strength of the hardened | cured material of a cement composition notably over a long period of time. Moreover, it is providing the cement composition which the intensity | strength of hardened | cured material can improve notably over a long term.

The cement additive of the present invention is
At least one (component A) selected from a polyethylene glycol having a weight average molecular weight of 150,000 or more (component a1) and a compound having a structure in which an alkylene oxide is added to a trihydric or higher polyhydric alcohol (component a2);
And at least one (component B) selected from oxycarboxylic acid or a salt thereof, keto acid or a salt thereof, sugar, and sugar alcohol.

  In one embodiment, the ratio of the mass of the B component to the A component is 10% to 500%.

  In one embodiment, the a1 component has a weight average molecular weight of 300,000 to 600,000.

  In one embodiment, the a2 component is an alkylene oxide adduct of glycerin, an alkylene oxide adduct of erythritol, a copolymer having a structural unit derived from an alkylene oxide adduct of methacrylic acid, an alkylene oxide adduct of sorbitol, It is at least one selected from a copolymer having a structural unit derived from an alkylene oxide adduct of 3-methyl-3-butenyl alcohol, and an alkylene oxide adduct to active hydrogen bonded to an amino group of polyethyleneimine. .

The cement composition of the present invention comprises:
At least one (component A) selected from a polyethylene glycol having a weight average molecular weight of 150,000 or more (component a1) and a compound having a structure in which an alkylene oxide is added to a trihydric or higher polyhydric alcohol (component a2);
At least one (component B) selected from oxycarboxylic acid or a salt thereof, keto acid or a salt thereof, sugar, sugar alcohol;
Cement.

  In one embodiment, the content of the component A in the cement composition is 0.001% by mass / cement to 1% by mass / cement with respect to the cement, and the B in the cement composition The content of the component is 0.001% by mass / cement to 1% by mass / cement with respect to the cement.

  In one embodiment, the ratio of the mass of the B component to the A component is 10% to 500%.

  In one embodiment, the a1 component has a weight average molecular weight of 300,000 to 600,000.

  In one embodiment, the a2 component is an alkylene oxide adduct of glycerin, an alkylene oxide adduct of erythritol, a copolymer having a structural unit derived from an alkylene oxide adduct of methacrylic acid, an alkylene oxide adduct of sorbitol, It is at least one selected from a copolymer having a structural unit derived from an alkylene oxide adduct of 3-methyl-3-butenyl alcohol, and an alkylene oxide adduct to active hydrogen bonded to an amino group of polyethyleneimine. .

  ADVANTAGE OF THE INVENTION According to this invention, the additive for cement which can improve the intensity | strength of the hardened | cured material of a cement composition notably over a long term can be provided. Moreover, the cement composition which can improve the intensity | strength of hardened | cured material notably over a long term can be provided.

  In the present specification, the expression “(meth) acryl” means “acryl and / or methacryl”, and the expression “(meth) acrylate” means “acrylate and / or methacrylate”. Means “allyl and / or methallyl”, and “(meth) acrolein” means “acrolein and / or methacrole”. It means "rain". Further, in the present specification, the expression “acid (salt)” means “acid and / or salt thereof”. Examples of the salt include alkali metal salts and alkaline earth metal salts. Specific examples include sodium salts and potassium salts.

≪Cement additive≫
The cement additive of the present invention is at least one selected from polyethylene glycol having a weight average molecular weight of 150,000 or more (a1 component) and a compound having a structure in which an alkylene oxide is added to a trihydric or higher polyhydric alcohol (a2 component). Species (component A) and at least one (component B) selected from oxycarboxylic acids or salts thereof, keto acids or salts thereof, sugars, sugar alcohols.

  A component may be 1 type and 2 or more types may be sufficient as it.

  B component may be 1 type and 2 or more types may be sufficient as it.

  By including both the A component and the B component, the cement additive of the present invention exhibits the effect that the strength of the cured product of the cement composition can be remarkably improved over a long period of time. Specifically, the effect of improving the long-term strength of the cured product of the cement composition that can be manifested by the present invention is the effect of improving the long-term strength of the cured product of the cement composition resulting from only the component A and the cement composition resulting from only the component B Compared with the effect expected from the sum of the effect of improving the long-term strength of the cured product, the synergistic effect is remarkably high.

  The content ratio of the total amount of the component A and the component B in the cement additive of the present invention is preferably 50% by mass to 100% by mass. If the content ratio of the total amount of the A component and the B component in the cement additive of the present invention is within the above range, the cement additive of the present invention makes the strength of the cured cement composition more prominent over a long period of time. Can be improved. When the content ratio of the total amount of component A and component B in the cement additive of the present invention is less than 50% by mass, the cement additive of the present invention improves the strength of the cured product of the cement composition over a long period of time. May be difficult.

  In one embodiment of the cement additive of the present invention, the cement additive of the present invention comprises an A component and a B component. In this case, the content ratio of the total amount of the component A and the component B in the cement additive of the present invention is 100% by mass.

  In another embodiment of the cement additive of the present invention, the cement additive of the present invention comprises an A component, a B component, and another component. 1 type may be sufficient as another component, and 2 or more types may be sufficient as it. In this case, the content ratio of the total amount of the component A and the component B in the cement additive of the present invention is preferably 50% by mass to 99.9% by mass, more preferably 55% by mass to 95% by mass. More preferably, it is 60 mass%-90 mass%, Most preferably, it is 62 mass%-90 mass%.

  The ratio of the mass of the B component to the A component (the mass of the B component / the mass of the A component) in the cement additive of the present invention is preferably 10% to 500%, more preferably 10% to 200%. More preferably, it is 10% to 100%, particularly preferably 10% to 80%, and most preferably 10% to 50%. If the ratio of the B component to the A component in the cement additive of the present invention is within the above range, the cement additive of the present invention can significantly improve the strength of the cured product of the cement composition over a long period of time. .

<A component>
The component A is at least one selected from a polyethylene glycol (a1 component) having a weight average molecular weight of 150,000 or more and a compound (a2 component) having a structure in which an alkylene oxide is added to a trihydric or higher polyhydric alcohol. By adopting such a component as the A component, the cement additive of the present invention can remarkably improve the strength of the cured product of the cement composition over a long period of time.

  If both the a1 component and the a2 component have the same weight average molecular weight, the a1 component having a linear structure has a higher viscosity than the a2 component having a branched structure. However, it is easy to handle.

(A1 component)
The a1 component is polyethylene glycol having a weight average molecular weight of 150,000 or more. When the weight average molecular weight of the a1 component is 150,000 or more, the cement additive of the present invention can remarkably improve the strength of the cured product of the cement composition over a long period of time.

  The a1 component may be one type or two or more types.

  The weight average molecular weight of the a1 component is preferably 150,000 to 5000000, more preferably 150,000 to 3000000, further preferably 180000 to 1000000, particularly preferably 200000 to 800000, and most preferably 300000 to 600000. is there. If the weight average molecular weight of the a1 component is within the above range, the cement additive of the present invention can remarkably improve the strength of the cured product of the cement composition over a long period of time.

(A2 component)
The a2 component is a compound having a structure in which an alkylene oxide is added to a trihydric or higher polyhydric alcohol. Since the a2 component is a compound having a structure in which an alkylene oxide is added to a trihydric or higher polyhydric alcohol, the cement additive of the present invention remarkably improves the strength of the cured cement composition over a long period of time. obtain.

  1 type may be sufficient as a2 component and 2 or more types may be sufficient as it.

  The trihydric or higher polyhydric alcohol may be a compound having three or more hydroxyl groups, and may be a low molecular compound or polymer, and any appropriate trihydric or higher polyhydric alcohol can be adopted. Such a trihydric or higher polyhydric alcohol is preferably a trivalent to 500 valent alcohol, more preferably a trivalent to 100 valent alcohol, and even more preferably a trivalent to 50 valent alcohol. . Examples of such polyhydric alcohols include glycerin, erythritol, sorbitol, and the like.

  Examples of the polyhydric alcohol include those obtained by polymerizing a monomer having a hydroxyl group. Examples of the monomer having a hydroxyl group include vinyl alcohol, allyl alcohol, methallyl alcohol, butenyl alcohol, 3-methyl-3-butenyl alcohol, 3-methyl-2-butenyl alcohol, 2-methyl-3-butyl. Examples include tenenyl alcohol. These may be polymerized alone or may be copolymerized with other polymerizable monomers. Polyhydric alcohols include those obtained by adding an alkylene oxide to active hydrogen bonded to the amino group of polyethyleneimine.

  The alkylene oxide is preferably an alkylene oxide having 2 to 10 carbon atoms, more preferably an alkylene oxide having 2 to 8 carbon atoms, more preferably 2 carbon atoms from the viewpoint that the effects of the present invention can be more manifested. -6 alkylene oxide, particularly preferably an alkylene oxide having 2 to 4 carbon atoms, and most preferably an alkylene oxide having 2 to 3 carbon atoms (that is, ethylene oxide, propylene oxide). Moreover, 1 type may be sufficient as alkylene oxide, and 2 or more types may be sufficient as it.

  The number of moles of alkylene oxide added per mole of polyhydric alcohol is preferably 5 moles or more, more preferably from 10 moles to 100,000 moles, still more preferably from 20 moles to 50,000 moles, still more preferably from 30 moles to It is 10,000 moles, particularly preferably 40 moles to 5000 moles, and most preferably 50 moles to 1000 moles. If the number of added moles of alkylene oxide per mole of polyhydric alcohol is within the above range, the cement additive of the present invention can significantly improve the strength of the cured product of the cement composition over a long period of time.

  The weight average molecular weight of the component a2 is preferably 3000 or more, more preferably from 4000 to 5000000, still more preferably from 5000 to 1000000, still more preferably from 8000 to 500000, still more preferably from 10000 to 300000. Especially preferably, it is 12000-150000, Most preferably, it is 13000-50000. If the weight average molecular weight of a2 component exists in the said range, the additive for cement of this invention can improve the intensity | strength of the hardened | cured material of a cement composition more notably over a long period of time.

  The a2 component may have any appropriate functional group. However, it is preferable that a2 component does not have a carboxyl group at the point which can fully express the effect of this invention.

  As a method for synthesizing the a2 component, any appropriate method such as a known method can be adopted as long as the effects of the present invention are not impaired. Examples of such a method include a method in which a monomer having a hydroxyl group is polymerized and then alkylene oxide is added, and a method in which alkylene oxide is first added to the monomer having a hydroxyl group and then polymerized.

  Specific examples of the component a2 include, for example, an alkylene oxide adduct of glycerin, an alkylene oxide adduct of erythritol, a copolymer having a structural unit derived from an alkylene oxide adduct of methacrylic acid, an alkylene oxide adduct of sorbitol, A copolymer having a structural unit derived from an alkylene oxide adduct of 3-methyl-3-butenyl alcohol, at least one selected from an alkylene oxide adduct to active hydrogen bonded to an amino group of polyethyleneimine, and the like Can be mentioned. Here, “an alkylene oxide adduct to an active hydrogen bonded to an amino group of polyethyleneimine” means any suitable alkylene oxide (such as ethylene oxide) is added to the active hydrogen bonded to the amino group of polyethyleneimine. This means an adduct added with an additional number of moles.

  When the a2 component is a copolymer having a structural unit derived from an alkylene oxide adduct of 3-methyl-3-butenyl alcohol, the copolymer may be a carboxyl group or It is preferable not to contain a salt (such as an alkali metal salt or an alkaline earth metal salt).

<B component>
The component B is at least one selected from oxycarboxylic acids or salts thereof, keto acids or salts thereof, sugars, and sugar alcohols.

  Any appropriate oxycarboxylic acid can be adopted as the oxycarboxylic acid. As such oxycarboxylic acid, for example, gluconic acid, tartaric acid, citric acid, malic acid, glucoheptonic acid, arabonic acid and the like can be mentioned, and preferably gluconic acid, It is at least one selected from tartaric acid, citric acid, and malic acid.

  Examples of the salt that can be employed as the salt of oxycarboxylic acid include inorganic salts or organic salts such as sodium, potassium, calcium, magnesium, ammonium, triethanolamine, and the like.

  Arbitrary appropriate keto acids can be employ | adopted as a keto acid. Examples of such keto acids include pyruvic acid, oxoglutaric acid, and the like, and pyruvic acid is preferred from the viewpoint that the effects of the present invention can be more manifested.

  Examples of the salt that can be adopted as the keto acid salt include inorganic salts and organic salts such as sodium, potassium, calcium, magnesium, ammonium, triethanolamine, and the like.

  Any appropriate sugar can be adopted as the sugar. Examples of such sugars include monosaccharides such as glucose, fructose, galactose, mannose, xylose, arabinose, ribose and isomerized sugar; disaccharides such as maltose, sucrose and lactose; trisaccharides such as raffinose; dextrin and the like Among them, glucose is preferable in that the effects of the present invention can be more manifested.

  Any appropriate sugar alcohol can be adopted as the sugar alcohol. As such a sugar alcohol, sorbitol is preferable in that the effect of the present invention can be expressed more.

<Other ingredients>
Any appropriate other component can be adopted as the other component that can be included in the cement additive of the present invention. As such other components, an alkanolamine compound is preferably used from the viewpoint that the effects of the present invention can be more manifested.

  Any appropriate alkanolamine compound can be adopted as the alkanolamine compound as long as the effects of the present invention are not impaired. Examples of such alkanolamine compounds include low molecular alkanolamine compounds and high molecular alkanolamine compounds.

  Examples of the low molecular alkanolamine compound include monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine (sometimes referred to as TIPA), methylethanolamine, methylisopropanolamine, Methyldiethanolamine, methyldiisopropanolamine, diethanolisopropanolamine, tetrahydroxyethylethylenediamine, N, N-bis (2-hydroxyethyl) 2-propanolamine, N, N-bis (2-hydroxypropyl) -N- (hydroxyethyl) ) Amine (sometimes referred to as hydroxyethyldiisopropanolamine (EDIPA)), N, N-bis (2-hydroxyethyl) -N- 2-hydroxypropyl) amine, N, N, N ', N'-tetrakis (2-hydroxypropyl) ethylenediamine (also referred to as Theda), tris (2-hydroxybutyl) amine, and the like. Among these, as a low molecular type alkanolamine compound, preferably, triisopropanolamine, N, N, N ′, N′-tetrakis (2-hydroxypropyl) ethylenediamine, N, N-bis (2-hydroxypropyl) are used. ) -N- (hydroxyethyl) amine. Other low molecular alkanolamine compounds include, for example, monomers having a triisopropanolamine skeleton.

  Examples of the polymer type alkanolamine compound include alkanolamines having a structure in which a part of alkanolamine is bonded to a polymer. Examples of such a high molecular alkanolamine compound include a polymer having a triisopropanolamine skeleton.

≪Cement composition≫
The cement composition of the present invention is at least one selected from a polyethylene glycol (a1 component) having a weight average molecular weight of 150,000 or more and a compound (a2 component) having a structure in which an alkylene oxide is added to a trihydric or higher polyhydric alcohol. (A component), at least 1 sort (B component) chosen from oxycarboxylic acid or its salt, keto acid or its salt, saccharide | sugar, and sugar alcohol, and a cement are included.

  The cement composition of the present invention preferably contains water and aggregate in addition to the A component, B component and cement, more preferably, the A component, B component, cement, water, aggregate and cement admixture. Including.

  As long as the cement composition of this invention contains A component, B component, and cement, as the preparation method, arbitrary appropriate preparation methods can be employ | adopted. For example, the A component and the B component may be blended as the form of the cement additive of the present invention to prepare the cement composition of the present invention, or the A component and the B component may be the form of the cement additive of the present invention. The cement composition of the present invention may be prepared by blending (for example, blending the A component and the B component separately) without adopting the above.

  Any appropriate aggregate such as fine aggregate (sand, etc.) or coarse aggregate (crushed stone, etc.) can be adopted as the aggregate. Examples of such aggregates include gravel, crushed stone, granulated slag, and recycled aggregate. Examples of such aggregates include refractory aggregates such as siliceous, clay, zircon, high alumina, silicon carbide, graphite, chromic, chromic, and magnesia.

  The content of the component A in the cement composition of the present invention is preferably 0.001% by mass / percent as a content (mass% / cement) with respect to the cement in that the effects of the present invention can be expressed more effectively. Cement to 1% by weight / cement, more preferably 0.003% by weight / cement to 0.50% by weight / cement, and even more preferably 0.005% by weight / cement to 0.30% by weight / cement. Yes, particularly preferably 0.007% by mass / cement to 0.15% by mass / cement, and most preferably 0.01% by mass / cement to 0.05% by mass / cement.

  The content of the component B in the cement composition of the present invention is preferably 0.001% by mass /% as a content (mass% / cement) with respect to the cement in that the effects of the present invention can be expressed more effectively. Cement to 1% by weight / cement, more preferably 0.002% by weight / cement to 0.50% by weight / cement, and even more preferably 0.003% by weight / cement to 0.30% by weight / cement. Yes, particularly preferably 0.004% by mass / cement to 0.15% by mass / cement, and most preferably 0.005% by mass / cement to 0.05% by mass / cement.

  When the A component and the B component are blended in the form of the cement additive of the present invention to form the cement composition of the present invention, the content of the cement additive of the present invention in the cement composition of the present invention is: The content (mass% / cement) with respect to the cement is preferably 0.001 mass% / cement to 1 mass% / cement, more preferably 0. 003 mass% / cement to 0.7 mass% / cement, more preferably 0.005 mass% / cement to 0.5 mass% / cement, and particularly preferably 0.007 mass% / cement to 0. 3% by mass / cement, most preferably 0.01% by mass / cement to 0.1% by mass / cement.

  In the cement composition of the present invention, the ratio of the mass of the B component to the A component (the mass of the B component / the mass of the A component) is preferably 10% to 500%, more preferably 10% to 200%. More preferably, it is 10% to 100%, particularly preferably 10% to 80%, and most preferably 10% to 50%. If the ratio of the B component to the A component in the cement composition of the present invention is within the above range, the strength of the cured product of the cement composition can be significantly improved over a long period of time.

  The cement admixture preferably contains a polymer for cement admixture in that the effects of the present invention can be expressed more effectively.

  Examples of the cement admixture polymer include a cement dispersant. Only one cement dispersant may be used, or two or more cement dispersants may be used.

  Examples of the cement dispersant include a sulfonic acid-based dispersant having a sulfonic acid group in the molecule, a polycarboxylic acid-based dispersant, and the like.

  Examples of the sulfonic acid-based dispersant include polyalkylaryl sulfonate-based sulfonic acid-based dispersants such as naphthalene sulfonic acid formaldehyde condensate, methyl naphthalene sulfonic acid formaldehyde condensate and anthracene sulfonic acid formaldehyde condensate; melamine sulfonic acid Melamine formalin sulfonate-based sulfonic acid dispersants such as formaldehyde condensates; Aromatic amino sulfonate-based sulfonic acid dispersants such as aminoaryl sulfonic acid-phenol-formaldehyde condensates; lignin sulfonates, Examples thereof include lignin sulfonate sulfonic acid dispersants such as modified lignin sulfonate; polystyrene sulfonate sulfonic acid dispersants;

  The cement admixture can contain any appropriate other cement additive (material) as long as the effects of the present invention are not impaired. Examples of such other cement additives (materials) include other cement additives (materials) exemplified in the following (1) to (11). The mixing ratio of the polymer for cement admixture that can be included in the cement admixture and such other cement additives (materials) is arbitrarily appropriate depending on the type and purpose of the other cement additives (materials) to be used. Various mixing ratios can be employed.

(1) Water-soluble polymer substances: nonionic cellulose ethers such as methylcellulose, ethylcellulose, carboxymethylcellulose; polysaccharides produced by microbial fermentation such as yeast glucan, xanthan gum, β-1.3 glucans; polyacrylamide, etc. .

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

(3) Early strengthening agent / accelerator: 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.

(4) Oxyalkylene antifoaming agents: polyoxyalkylene alkyl ethers such as diethylene glycol heptyl ether; polyoxyalkylene acetylene ethers; (poly) oxyalkylene fatty acid esters; polyoxyalkylene sorbitan fatty acid esters; polyoxyalkylene alkyl (Aryl) ether sulfate ester salt; polyoxyalkylene alkyl phosphate ester; polyoxypropylene polyoxyethylene laurylamine (1-20 mol addition of propylene oxide, 1-20 mol addition product of ethylene oxide, etc.), alkylene oxide was added Polyoxyalkylene alkyl amines such as amines derived from fatty acids obtained from cured beef tallow (propylene oxide 1-20 mol addition, ethylene oxide 1-20 mol addition products, etc.) S; polyoxyalkylene amide.

(5) Antifoaming agents other than oxyalkylene type: Mineral oil type, fat type, fatty acid type, fatty acid ester type, alcohol type, amide type, phosphate ester type, metal soap type, silicone type and the like.

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

(7) Other surfactants: various anionic surfactants; various cationic surfactants such as alkyltrimethylammonium chloride; various nonionic surfactants; various amphoteric surfactants.

(8) Waterproofing agent: fatty acid (salt), fatty acid ester, oil and fat, silicon, paraffin, asphalt, wax and the like.

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

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

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

  Other known cement additives (materials) include cement wetting agents, thickeners, separation reducing agents, flocculants, drying shrinkage reducing agents, strength enhancers, self-leveling agents, colorants, fungicides, and the like. be able to. These known cement additives (materials) may be only one kind or two or more kinds.

  Arbitrary appropriate cement can be employ | adopted as a cement contained in the cement composition of this invention. Examples of such cements include Portland cement (ordinary, early strength, ultra-early strength, moderate heat, sulfate resistance and low alkali types thereof), 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, Low Fly Ash Mixing) Exothermic blast furnace cement, belite high-content cement), ultra-high strength cement, cement-based solidified material, eco-cement (cement produced from one or more of municipal waste incineration ash and sewage sludge incineration ash). Furthermore, fine powders and gypsum such as blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica powder, and limestone powder may be added to the cement composition of the present invention. The cement contained in the cement composition of the present invention may be only one type or two or more types.

In the cement composition of the present invention, any appropriate value can be set as the unit water amount per 1 m ³ , the amount of cement used, and the water / cement ratio. Such values, preferably, unit water is ^{100kg / m 3 ~185kg / m 3} , the amount of cement used is ^{250kg / m 3 ~800kg / m 3} , water / cement ratio (mass ratio) = is 0.1 to 0.7, more preferably, a unit water amount is ^{120kg / m 3 ~175kg / m 3} , the amount of cement used is ^{270kg / m 3 ~800kg / m 3} , water / cement ratio ( (Mass ratio) = 0.12 to 0.65. As described above, the cement composition of the present invention can be widely used from poor blending to rich blending, and can be used for both high-strength concrete with a large amount of unit cement and poor blended concrete with a unit cement amount of 300 kg / m ³ or less. It is valid.

  When the cement composition of the present invention contains a polymer for cement admixture, any appropriate content ratio may be adopted as the content of the polymer for cement admixture in the cement composition of the present invention depending on the purpose. obtain. As such a content ratio, when used for mortar or concrete using hydraulic cement, the content ratio of the polymer for cement admixture with respect to 100 parts by mass of cement is preferably 0.01 parts by mass to 10 parts by mass. More preferably, it is 0.02 mass part-5 mass parts, More preferably, it is 0.05 mass part-3 mass parts. By setting it as such a content rate, various favorable effects, such as reduction of unit water amount, an increase in intensity | strength, and an improvement in durability, are brought about. When the content ratio is less than 0.01 parts by mass, sufficient performance may not be exhibited. When the content ratio exceeds 10 parts by mass, the effect that can be achieved substantially reaches its peak and also from the economical aspect. May be disadvantageous.

  As a content ratio of the cement admixture in the cement composition of the present invention, any appropriate content ratio can be adopted depending on the purpose. As such a content ratio, the content ratio of the cement admixture with respect to 100 parts by mass of cement is preferably 0.01 parts by mass to 10 parts by mass, more preferably 0.05 parts by mass to 8 parts by mass, More preferably, it is 0.1 mass part-5 mass parts. When the content ratio is less than 0.01 parts by mass, sufficient performance may not be exhibited. When the content ratio exceeds 10 parts by mass, the effect that can be achieved substantially reaches its peak and also from the economical aspect. May be disadvantageous.

  The cement composition of the present invention can be effective for ready-mixed concrete, concrete for concrete secondary products, concrete for centrifugal molding, concrete for vibration compaction, steam-cured concrete, shotcrete, and the like. The cement composition of the present invention includes medium-fluidity concrete (concrete with a slump value of 22 to 25 cm), high-fluidity concrete (concrete with a slump value of 25 cm or more and a slump flow value of 50 to 70 cm), self-filling concrete, self It can also be effective for mortar and concrete that require high fluidity, such as leveling materials.

  The cement composition of the present invention may be prepared by blending the constituent components by any appropriate method. For example, the method etc. which knead | mix a structural component in a mixer are mentioned.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these Examples. Unless otherwise specified, the term “part” means mass part, and the term “%” means mass%.

<Conditions for weight average molecular weight analysis>
Regarding the weight average molecular weight of polyethylene glycol, if it is a commercially available product and is disclosed on the catalog or website, its value is used unless otherwise specified in the examples and comparative examples (for example, “measured value” etc.). Adopted (in case of other expressions such as “average molecular weight” published on the catalog or homepage, the value was adopted).
Columns used: TSK guard column α + TSK gel α-5000 + TSK gel α-4000 + TSK gel α-3000, manufactured by Tosoh Corporation and used one by one.
Eluent: sodium dihydrogen phosphate · 2H ₂ O: 62.4 g, disodium hydrogen phosphate · 12H ₂ O: 143.3 g dissolved in ion-exchanged water: 774.3 g, acetonitrile: 2000 g A mixed solution was used.
Detector: Triple detector “Model 302 light scattering detector” manufactured by Viscotek, 90 ° scattering angle for right angle light scattering, 7 ° scattering angle for low angle light scattering, 18 μL for cell capacity, and 670 nm for wavelength.
Standard sample: Polyethylene glycol SE-8 (Mw = 107000) manufactured by Tosoh Corporation was used, its dn / dC was 0.135 ml / g, and the refractive index of the eluent was determined to be 1.333 to determine the apparatus constant.
-Injection amount standard sample: 100 μL of the solution dissolved in the eluent so as to have a polymer concentration of 0.2 vol% was injected.
Sample: 100 μL of a solution dissolved in the eluent so that the polymer concentration was 1.0 vol% was injected.
・ Flow rate: 0.8ml / min
-Column temperature: 40 ° C

<Measurement of 28-day compressive strength>
(Measurement of flow value and air volume)
Ordinary Portland cement (made by Taiheiyo Cement) as cement, Oikawa water-based land sand as fine aggregate, Aomi crushed stone as coarse aggregate, A component and / or B component, water reducing agent, tap water as kneading water, cement : 382 kg / m ³ , water: 172 kg / m ³ , fine aggregate: 796 kg / m ³ , coarse aggregate: 930 kg / m ³ , fine aggregate rate (fine aggregate / fine coarse aggregate + coarse aggregate) ( Volume ratio): A cement composition was prepared with a composition of 47% and water / cement ratio (mass ratio) = 0.45.
In addition, the temperature of the material used for the measurement, the forced kneading mixer, and the measuring instruments are adjusted in the above measurement temperature atmosphere so that the temperature of the cement composition is 20 ° C. The kneading and each measurement are performed as described above. The measurement was performed under an atmosphere of the temperature. Further, in order to avoid the influence of bubbles in the cement composition on the fluidity of the cement composition, an oxyalkylene-based antifoaming agent is used as necessary so that the air amount becomes 1.0 ± 0.5%. Adjusted.
Concrete was produced in a kneading time of 90 seconds using a forced kneading mixer under the above conditions, and the flow value and the amount of air were measured. In addition, the measurement of the flow value and the air amount was performed based on Japanese Industrial Standards (JIS-A-1101, 1128). Moreover, the addition amount of A component and / or B component, and a water reducing agent was made into the addition amount used as the flow value of 37.5-42.5 cm.
(28 days compression strength)
After measuring the flow value and the air amount, a sample for compressive strength test was prepared, and the compressive strength after 28 days was measured under the following conditions.
Specimen creation: 100mm x 200mm
Specimen curing (28 days): Temperature of about 20 ° C, humidity 60%, constant temperature and humidity air curing for 24 hours, then curing the specimen in water for 27 days: Specimen surface polishing (use of specimen polishing finish machine)
Compressive strength measurement: Automatic compressive strength meter (Maekawa Seisakusho)
In the examples and comparative examples, “strength (%) vs. comparative example 28 or comparative example 29 ^* ” means that the example using the copolymer (1) as a water reducing agent and the comparative example is comparative example 28 (copolymerization). About the ratio and the strength ratio when the 28-day compressive strength measured in the blank test using the coalescence (1) is 100 (%), Examples using the copolymer (2) as a water reducing agent, Comparative Examples Is the strength ratio when the 28-day compressive strength measured in Comparative Example 29 (corresponding to a blank test using the copolymer (2)) is taken as 100. In addition, the “strength (%) synergistic effect component” means “strength (%) − 100 (% ) "And" Strength (%)-100 (%) in the corresponding comparative example when only the used B component is used "is X (%), and" the A component and the B component are used in combination. " “Y (%) − X (%)” when “strength (%) − 100 (%)” in the examples is Y (%). The larger this value, the greater the A component and the B component. It shows that the synergistic effect on simple sum by using together is great.

[Production Example 1]: Manufacture of polymer for cement admixture Ion exchange in a glass reaction vessel equipped with a Jimroth condenser, a Teflon (registered trademark) stirring blade and stirrer with stirring seal, a nitrogen introduction tube, and a temperature sensor 80.0 parts of water was charged and the mixture was heated to 70 ° C. while stirring at 250 rpm and introducing nitrogen at 200 mL / min. Next, a mixed solution of 133.4 parts of methoxypolyethyleneglycol monomethacrylate (average number of added moles of ethylene oxide 9), 26.6 parts of methacrylic acid, 1.53 parts of mercaptopropionic acid and 106.7 parts of ion-exchanged water Was added dropwise over 4 hours, and simultaneously, a mixed solution of 1.19 parts of ammonium persulfate and 50.6 parts of ion-exchanged water was added dropwise over 5 hours. The polymerization reaction was completed by maintaining at 70 ° C. for 1 hour after completion of the dropping. And it neutralized with sodium hydroxide aqueous solution, and obtained the aqueous solution of the copolymer (1) of the weight average molecular weight 100000.

[Production Example 2]: Production of polymer for cement admixture Jimroth cooling tube, Teflon (registered trademark) stirring blade and stirrer with stirring seal, nitrogen introduction tube, glass reaction vessel equipped with temperature sensor, 3 -Methyl-3-buten-1-ol (isoprenol) added with ethylene oxide (average number of moles of ethylene oxide added 50) (hereinafter referred to as IPN-50) (80% aqueous solution) 198.2 parts, Charge 0.32 parts of acrylic acid, 12.47 parts of hydrogen peroxide (2% aqueous solution), 44.75 parts of ion-exchanged water, and warm to 58 ° C while introducing nitrogen at 200 mL / min while stirring at 250 rpm. did. Next, a mixed solution composed of 27.12 parts of acrylic acid and 108.5 parts of ion-exchanged water was dropped over 3 hours, and at the same time 0.74 parts of L-ascorbic acid, 1.61 parts of 3-mercaptopropionic acid, ions A mixed solution consisting of 86.31 parts of exchange water was added dropwise over 3 hours and 30 minutes. The polymerization reaction was completed by maintaining at 58 ° C. for 1 hour after the completion of the dropping. And it neutralized with sodium hydroxide aqueous solution, and obtained the aqueous solution of the copolymer (2) of the weight average molecular weight 140000.

[Production Example 3]
Dimroth condenser, Teflon (registered trademark) stirring blade and stirrer with stirring seal, nitrogen introduction tube, glass reaction vessel equipped with temperature sensor, charged with 103.7 parts of ion-exchanged water, stirred at 250 rpm, The mixture was heated to 70 ° C. while introducing nitrogen at 200 mL / min. Next, a mixed solution consisting of 188 parts of IPN-50 (80% aqueous solution), 9.6 parts of acrylamide, and 53.07 parts of ion-exchanged water was dropped over 4 hours, and at the same time, 0.13 part of 3-mercaptopropionic acid, A mixed solution consisting of 29.47 parts of ion-exchanged water, 0.48 part of ammonium persulfate and 15.55 parts of ion-exchanged water were added dropwise over 5 hours. The polymerization reaction was completed by maintaining at 70 ° C. for 1 hour after completion of the dropping. And it neutralized with sodium hydroxide aqueous solution, and obtained the aqueous solution of the copolymer (3) of the weight average molecular weight 130000.

[Production Example 4]
Dimroth condenser, Teflon (registered trademark) stirring blade and stirrer with stirring seal, nitrogen introduction tube, 117.3 parts of ion-exchanged water in a glass reaction vessel equipped with a temperature sensor, with stirring at 250 rpm, The mixture was heated to 70 ° C. while introducing nitrogen at 200 mL / min. Next, a mixed solution consisting of 188 parts of IPN-50 (80% aqueous solution), 9.6 parts of acrylamide, and 53.07 parts of ion-exchanged water was dropped over 4 hours, and at the same time, 0.48 parts of ammonium persulfate and ion-exchanged water were added. 31.59 parts of the mixed solution was added dropwise over 5 hours. The polymerization reaction was completed by maintaining at 70 ° C. for 1 hour after completion of the dropping. And it neutralized with sodium hydroxide aqueous solution, and obtained the aqueous solution of the copolymer (4) of the weight average molecular weight 210000.

[Production Example 5]
Dimroth cooling tube, Teflon (registered trademark) stirring blade and stirrer with stirring seal, nitrogen introduction tube, and glass reaction vessel equipped with a temperature sensor were charged with 103.7 parts of ion-exchanged water and stirred at 250 rpm. The mixture was heated to 70 ° C. while introducing nitrogen at 200 mL / min. Next, a mixed solution consisting of 180 parts of IPN-50 (80% aqueous solution), 16.0 parts of hydroxyethyl acrylate, and 44.0 parts of ion-exchanged water was added dropwise over 4 hours, and simultaneously, 3-mercaptopropionic acid 0 A mixed solution composed of 0.06 part and 40.2 parts of ion-exchanged water and a mixed solution composed of 1.98 parts of ammonium persulfate and 64.05 parts of ion-exchanged water were added dropwise over 5 hours. After completion of the dropwise addition, the polymerization reaction was completed by maintaining at 70 ° C. for 1 hour. And it neutralized with sodium hydroxide aqueous solution, and obtained the aqueous solution of the copolymer (5) of the weight average molecular weight 350,000.

[Production Example 6]
Dimroth condenser, Teflon (registered trademark) stirring blade and stirrer with stirring seal, nitrogen introduction tube, and glass reaction vessel equipped with a temperature sensor were charged with 143.97 parts of ion-exchanged water and stirred at 250 rpm. The mixture was heated to 70 ° C. while introducing nitrogen at 200 mL / min. Next, a mixed solution consisting of 180 parts of IPN-50 (80% aqueous solution), 16.0 parts of hydroxyethyl acrylate, and 44.0 parts of ion-exchanged water was dropped over 4 hours, and at the same time, 1.98 parts of ammonium persulfate. And a mixed solution consisting of 64.05 parts of ion-exchanged water was added dropwise over 5 hours. After completion of the dropwise addition, the polymerization reaction was completed by maintaining at 70 ° C. for 1 hour. And it neutralized with sodium hydroxide aqueous solution, and obtained the aqueous solution of the copolymer (6) of the weight average molecular weight 740000.

[Example 1]
PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000 (described in http://www.wako-chem.co.jp/siyaku/qa/ccn/pdf/ccn52.pdf) Average molecular weight value), the same applies hereinafter) and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) under the conditions shown in Table 1 to prepare a cement additive (1).

[Example 2]
PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000), tartaric acid (manufactured by Wako Pure Chemical Industries, Ltd.) are blended under the conditions shown in Table 1, and cement additive (2) Was prepared.

Example 3
PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000) and citric acid (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and an additive for cement (3 ) Was prepared.

Example 4
PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000), malic acid (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and an additive for cement (4 ) Was prepared.

Example 5
A cement additive (5) was prepared in the same manner as in Example 1 except that the amount of PEG 500,000 was changed as shown in Table 1.

Example 6
A cement additive (6) was prepared in the same manner as in Example 2 except that the amount of PEG 500,000 was changed as shown in Table 1.

Example 7
A cement additive (7) was prepared in the same manner as in Example 3 except that the blending amount of PEG 500,000 was changed as shown in Table 1.

Example 8
A cement additive (8) was prepared in the same manner as in Example 4 except that the amount of PEG 500,000 was changed as shown in Table 1.

Example 9
PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000) and glucose (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and an additive for cement (9) Was prepared.

Example 10
A cement additive (10) was prepared in the same manner as in Example 1 except that the amount of PEG 500,000 was changed as shown in Table 1.

Example 11
A cement additive (11) was prepared in the same manner as in Example 5 except that the blending amount of sodium gluconate was changed as shown in Table 1.

Example 12
A cement additive (12) was prepared in the same manner as in Example 5 except that the blending amount of sodium gluconate was changed as shown in Table 1.

Example 13
A cement additive (13) was prepared in the same manner as in Example 6 except that the amount of tartaric acid was changed as shown in Table 1.

Example 14
PEG 2 million (polyethylene glycol 2,000,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 2 million (http://www.wako-chem.co.jp/siyaku/qa/ccn/pdf/ccn52.pdf) The average molecular weight value described in 1), the same applies hereinafter) and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1 to prepare a cement additive (14).

Example 15
The copolymer (3) obtained in Production Example 3 and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1 to prepare a cement additive (15).

Example 16
A cement additive (16) was prepared in the same manner as in Example 14 except that the blending amounts of the copolymer (3) and sodium gluconate were changed as shown in Table 1.

Example 17
The copolymer (3) obtained in Production Example 3 and tartaric acid (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1 to prepare a cement additive (17).

Example 18
The copolymer (4) obtained in Production Example 4 and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1 to prepare a cement additive (18).

Example 19
A cement additive (19) was prepared in the same manner as in Example 17 except that the amount of sodium gluconate was changed as shown in Table 1.

Example 20
The copolymer (4) obtained in Production Example 4 and citric acid (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1 to prepare a cement additive (20).

Example 21
The copolymer (5) obtained in Production Example 5 and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1 to prepare a cement additive (21).

[Example 22]
A cement additive (22) was prepared in the same manner as in Example 20 except that the amount of sodium gluconate was changed as shown in Table 1.

Example 23
The copolymer (5) obtained in Production Example 5 and sorbitol (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1 to prepare a cement additive (23).

Example 24
The copolymer (6) obtained in Production Example 6 and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1 to prepare a cement additive (24).

Example 25
The copolymer (6) obtained in Production Example 6 and malic acid (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1 to prepare a cement additive (25).

Example 26
ESP (weight average molecular weight = 23,000, polyethyleneimine (weight average molecular weight = 600) with 20 mol of ethylene oxide added to 1 mol of active hydrogen of amino group), sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) The cement additive (26) was prepared by blending under the conditions of 1.

Example 27
A cement additive (27) was prepared in the same manner as in Example 25 except that the blending amounts of ESP and sodium gluconate were changed as shown in Table 1.

Example 28
SB300 (weight average molecular weight = 13000, 300 mol of ethylene oxide added to 1 mol of sorbitol), sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and an additive for cement (28 ) Was prepared.

Example 29
A cement additive (29) was prepared in the same manner as in Example 27 except that the blending amount of sodium gluconate was changed as shown in Table 1.

Example 30
PEG200,000 (polyethylene glycol, manufactured by Aldrich, weight average molecular weight = 313000 (actual value)), sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and EDIPA (hydroxyethyldiisopropanolamine) , Manufactured by Aldrich) in an amount of 0.02% by mass / cement to prepare a cement additive (30).

Example 31
PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000) and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and TIPA (triisopropanol) was added. Amine (manufactured by Wako Pure Chemical Industries, Ltd.) was added in an amount of 0.005% by mass / cement to prepare a cement additive (31).

[Example 32]
PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000) and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and EDIPA (hydroxyethyl) Diisopropanolamine (manufactured by Aldrich) was added in an amount of 0.01% by mass / cement to prepare a cement additive (32).

Example 33
PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000), sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and further, THEDA (N, N, N ′, N′-tetrakis (2-hydroxypropyl) ethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd.) was added in an amount of 0.005% by mass / cement to prepare a cement additive (33).

Example 34
ESP (weight average molecular weight = 23,000, polyethyleneimine (weight average molecular weight = 600) with 20 mol of ethylene oxide added to 1 mol of active hydrogen of amino group), sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) 1 was further added, and TIPA (triisopropanolamine, manufactured by Wako Pure Chemical Industries, Ltd.) was added in an amount of 0.02% by mass / cement to prepare a cement additive (34).

Example 35
SB300 (weight average molecular weight = 13,000, 300 mol of ethylene oxide added to 1 mol of sorbitol), sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and TIPA (triisopropanolamine) was added. , Manufactured by Wako Pure Chemical Industries, Ltd.) was added in an amount of 0.01% by mass / cement to prepare a cement additive (35).

Example 36
The copolymer (3) obtained in Production Example 3 and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and further, THEDA (N, N, N ′, N′-tetrakis ( 2-hydroxypropyl) ethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd.) was added in an amount of 0.01% by mass / cement to prepare a cement additive (36).

Example 37
The copolymer (4) obtained in Production Example 4 and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and TIPA (triisopropanolamine, manufactured by Wako Pure Chemical Industries, Ltd.) was further added. Cement additive (37) was prepared by adding 0.01% by mass / cement.

Example 38
The copolymer (5) obtained in Production Example 5 and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and EDIPA (hydroxyethyl diisopropanolamine, manufactured by Aldrich) was added to 0. Addition was made in an amount of 0.005% by mass / cement to prepare a cement additive (38).

Example 39
The copolymer (6) obtained in Production Example 6 and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended under the conditions shown in Table 1, and further, THEDA (N, N, N ′, N′-tetrakis ( 2-hydroxypropyl) ethylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd.) was added in an amount of 0.005% by mass / cement to prepare a cement additive (39).

[Comparative Example 1]
As shown in Table 2, PEG 20,000 (polyethylene glycol 20,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 15000 to 25000 (http://www.wako-chem.co.jp/siyaku/qa/ccn/ The average molecular weight value described in pdf / ccn52.pdf, the same applies hereinafter) was used as the cement additive (C1).

[Comparative Example 2]
As shown in Table 2, PEG 100,000 (polyethylene glycol, manufactured by Aldrich, weight average molecular weight = 148000 (actual value)) was used as the additive for cement (C2).

[Comparative Example 3]
As shown in Table 2, PEG 200,000 (polyethylene glycol, manufactured by Aldrich, weight average molecular weight = 313000 (actual value)) was used as the cement additive (C3).

[Comparative Example 4]
As shown in Table 2, PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000) was used as an additive for cement (C4).

[Comparative Example 5]
As shown in Table 2, PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000) was used as the cement additive (C5).

[Comparative Example 6]
As shown in Table 2, PEG 500,000 (polyethylene glycol 500,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 500,000) was used as the cement additive (C6).

[Comparative Example 7]
As shown in Table 2, PEG 2 million (polyethylene glycol 2,000,000, manufactured by Wako Pure Chemical Industries, Ltd., weight average molecular weight = 2 million) was used as an additive for cement (C7).

[Comparative Example 8]
As shown in Table 2, the copolymer (3) obtained in Production Example 3 was used as an additive for cement (C8).

[Comparative Example 9]
As shown in Table 2, the copolymer (3) obtained in Production Example 3 was used as an additive for cement (C9).

[Comparative Example 10]
As shown in Table 2, the copolymer (4) obtained in Production Example 4 was used as an additive for cement (C10).

[Comparative Example 11]
As shown in Table 2, the copolymer (5) obtained in Production Example 5 was used as an additive for cement (C11).

[Comparative Example 12]
As shown in Table 2, the copolymer (6) obtained in Production Example 6 was used as an additive for cement (C12).

[Comparative Example 13]
As shown in Table 2, the copolymer (6) obtained in Production Example 6 was used as an additive for cement (C13).

[Comparative Example 14]
As shown in Table 2, ESP (weight average molecular weight = 23000, polyethyleneimine (weight average molecular weight = 600) with 20 mol of ethylene oxide added to 1 mol of active hydrogen of amino group) Cement additive (C14) It was.

[Comparative Example 15]
As shown in Table 2, ESP (weight average molecular weight = 23000, polyethyleneimine (weight average molecular weight = 600) with 20 mol of ethylene oxide added to 1 mol of active hydrogen of amino group) Cement additive (C15) It was.

[Comparative Example 16]
As shown in Table 2, SB300 (weight average molecular weight = 13000, 300 mol of ethylene oxide added to 1 mol of sorbitol) was used as an additive for cement (C16).

[Comparative Example 17]
As shown in Table 2, SB300 (weight average molecular weight = 13000, 300 mol of ethylene oxide added to 1 mol of sorbitol) was used as an additive for cement (C17).

[Comparative Example 18]
As shown in Table 2, sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the cement additive (C18).

[Comparative Example 19]
As shown in Table 2, sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the cement additive (C19).

[Comparative Example 20]
As shown in Table 2, sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the cement additive (C20).

[Comparative Example 21]
As shown in Table 2, tartaric acid (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the cement additive (C21).

[Comparative Example 22]
As shown in Table 2, tartaric acid (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the cement additive (C22).

[Comparative Example 23]
As shown in Table 2, tartaric acid (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the cement additive (C23).

[Comparative Example 24]
As shown in Table 2, citric acid (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the cement additive (C24).

[Comparative Example 25]
As shown in Table 2, malic acid (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the cement additive (C25).

[Comparative Example 26]
As shown in Table 2, glucose (manufactured by Wako Pure Chemical Industries, Ltd.) was used as an additive for cement (C26).

[Comparative Example 27]
As shown in Table 2, sorbitol (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the cement additive (C27).

[Examples 40 to 78]
28 days using a water reducing agent, component A and component B (in Examples 69 to 78, other components other than component A and component B used in Examples 30 to 39) under the conditions shown in Table 3 The compressive strength was measured. That is, the cement composition was prepared and the compressive strength was measured on the 28th. In addition, the mixture ratio with respect to the cement of other components was made the same as that of Examples 30-40.
In preparing the cement composition, as components A and B (in Examples 69 to 78, other components other than the components A and B used in Examples 30 to 39) were used. Even when the cement additives (1) to (39) obtained in 39 are used, the A component and the B component (in Examples 69 to 78, the A component used in Examples 30 to 39) The same result was obtained even when the other components other than the component B and the component B) were added independently.
The results are shown in Table 3.

[Comparative Examples 28-56]
Under the conditions shown in Table 4, the 28-day compressive strength was measured using the water reducing agent and the cement additives (C1) to (C27) obtained in Comparative Examples 1 to 27. That is, the cement composition was prepared and the compressive strength was measured on the 28th.
The results are shown in Table 4.

As shown in Tables 3 and 4, the strength ratio of the 28-day compression strength in Examples 40 to 78 using both the A component and the B component was “in the corresponding comparative example using only the A component used in each example. Compared to the simple sum of “strength (%) − 100 (%)” and “strength (%) − 100 (%) in the corresponding comparative example using only the B component used in each example”, “Example Strength (%) − 100 (%) ”(“ Strength (%) vs. Comparative Example 28 or Comparative Example 29 ^* ”in Table 3) was significantly increased, and a remarkable synergistic effect was observed.

The cement additive of the present invention is suitably used for cement compositions such as mortar and concrete.

Claims (9)

At least one (component A) selected from a polyethylene glycol having a weight average molecular weight of 150,000 or more (component a1) and a compound having a structure in which an alkylene oxide is added to a trihydric or higher polyhydric alcohol (component a2);
Oxycarboxylic acid or a salt thereof, keto acid or a salt thereof, at least one selected from sugar and sugar alcohol (component B),
Additive for cement.   The additive for cement according to claim 1, wherein a ratio of the mass of the B component to the A component is 10% to 500%.   The additive for cement according to claim 1 or 2, wherein the a1 component has a weight average molecular weight of 300,000 to 600,000.   The a2 component is an alkylene oxide adduct of glycerin, an alkylene oxide adduct of erythritol, a copolymer having a structural unit derived from an alkylene oxide adduct of methacrylic acid, an alkylene oxide adduct of sorbitol, 3-methyl-3-butyl A copolymer having a structural unit derived from an alkylene oxide adduct of tenenyl alcohol, and at least one selected from an alkylene oxide adduct to active hydrogen bonded to an amino group of polyethyleneimine, The additive for cement according to any one of the above. At least one (component A) selected from a polyethylene glycol having a weight average molecular weight of 150,000 or more (component a1) and a compound having a structure in which an alkylene oxide is added to a trihydric or higher polyhydric alcohol (component a2);
At least one (component B) selected from oxycarboxylic acid or a salt thereof, keto acid or a salt thereof, sugar, sugar alcohol;
Cement, and
Cement composition.   The content of the component A in the cement composition is 0.001% by mass / cement to 1% by mass / cement with respect to the cement, and the content of the component B in the cement composition is The cement composition according to claim 5, which is 0.001% by mass / cement to 1% by mass / cement with respect to cement.   The cement composition of Claim 6 whose ratio of the mass of the said B component with respect to the said A component is 10%-500%.   The cement composition according to claim 6 or 7, wherein the a1 component has a weight average molecular weight of 300,000 to 600,000. The a2 component is an alkylene oxide adduct of glycerin, an alkylene oxide adduct of erythritol, a copolymer having a structural unit derived from an alkylene oxide adduct of methacrylic acid, an alkylene oxide adduct of sorbitol, 3-methyl-3-butyl A copolymer having a structural unit derived from an alkylene oxide adduct of tenenyl alcohol, and at least one selected from an alkylene oxide adduct to an active hydrogen bonded to an amino group of polyethyleneimine, The cement composition according to any one of the above.