JP7027105B2 - Cement composition - Google Patents

Description

The present invention relates to cement strength enhancers, cement additives, and cement compositions.

Cement compositions generally contain cement, aggregates and water, and are usually required to increase fluidity and reduce water.

Recently, there have been increasing demands for cement compositions to improve the strength performance of cured products of cement compositions. For example, depending on the use of the cement composition, early development of strength 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, it is required to improve the strength of the cured product of the cement composition over a long period of time (for example, to improve the strength at the level of 4 weeks).

Japanese Unexamined Patent Publication No. 2011-84459

An object of the present invention is to provide a cement strength improver and a cement additive capable of significantly improving the strength of a cured product of a cement composition over a long period of time. Another object of the present invention is to provide a cement composition containing such a cement strength improver.

The cement strength improver in one embodiment of the present invention contains a polysaccharide having a gel-forming ability to gel in alkaline water.

In one preferred embodiment, the polysaccharide is at least one selected from the group consisting of alginic acid or a salt thereof, an alginic acid ester, and glucomannan.

The cement additive in one embodiment of the present invention has the above-mentioned cement strength improving agent and at least one selected from the group consisting of the following A component, B component, and C component.
Component A: A compound having a structure in which 5 mol or more of alkylene oxide is added to 1 mol of alcohol.
Component B: Alkanolamine compound.
Component C: At least one selected from the group consisting of oxycarboxylic acid or a salt thereof, keto acid or a salt thereof, sugar, and sugar alcohol.

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

In one preferred embodiment, the component B is at least one selected from the group consisting of triisopropanolamine, N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine, and diisopropanolethanolamine. Is.

The cement composition in one embodiment of the present invention contains the above-mentioned cement strength improver.

In one preferred embodiment, the cement composition further comprises at least one selected from the group consisting of the following A, B, and C components.
Component A: A compound having a structure in which 5 mol or more of alkylene oxide is added to 1 mol of alcohol.
Component B: Alkanolamine compound.
Component C: At least one selected from the group consisting of oxycarboxylic acid or a salt thereof, keto acid or a salt thereof, sugar, and sugar alcohol.

According to the present invention, it is possible to provide a cement strength improver and a cement additive that can significantly improve the strength of a cured product of a cement composition over a long period of time. Further, it is possible to provide a cement composition containing such a cement strength improver.

In the present specification, the expression "(meth) acrylic" means "acrylic and / or methacrolein", and the expression "(meth) acrylate" means "acrylate and / or methacrylate". When the expression "(meth) allyl" is used, it means "allyl and / or methacrolein", and when the expression "(meth) acrolein" is used, "acrolein and / or methacrolein" is used. It means "rain". Further, when the expression "acid (salt)" is used in the present specification, it means "acid and / or a salt thereof". Examples of the salt include alkali metal salts and alkaline earth metal salts, and specific examples thereof include sodium salts, potassium salts, calcium salts and the like.

≪1. Cement strength improver ≫
The cement strength improver contains a polysaccharide having a gel-forming ability to gel in alkaline water.

The cement strength improver can significantly improve the strength of the cured product of the cement composition over a long period of time. That is, the cement strength improver is a specific agent for improving the strength of mortar containing cement and concrete, and exhibits an excellent effect of significantly improving the strength of a cured product of a cement composition over a long period of time. sell.

As used herein, the term "gel-forming ability to gel in alkaline water" refers to, for example, in an alkaline water such as gelling via the metal ion in a liquid containing a metal ion such as calcium ion to form a gel. It means the ability to gel and form a gel.

The content of the polysaccharide having a gel-forming ability to gel in alkaline water is preferably 50% by mass to 100% by mass, and more preferably 70% by mass to 100% by mass in the cement strength improving agent. It is more preferably 90 to 100% by mass, particularly preferably 95% by mass to 100% by mass, and most preferably substantially 100% by mass. When the content ratio of the polysaccharide having a gel-forming ability to gel in alkaline water in the cement strength improving agent 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 strength improver may contain any suitable component other than a polysaccharide having a gel-forming ability to gel in alkaline water, as long as the effect of the present invention is not impaired.

Examples of the polysaccharide having a gel-forming ability to gel in alkaline water include at least one selected from the group consisting of alginic acid or a salt thereof, alginic acid ester, and glucomannan.

Preferred examples of alginic acid or a salt thereof include sodium alginate. Examples of the alginic acid ester include propylene glycol alginate and lauroyl alginate, and propylene glycol alginate is preferable. Alginic acid or a salt thereof, alginic acid ester, is typically a polysaccharide having a gel-forming ability to gel via calcium ions.

Glucomannan is a polysaccharide capable of gelling in alkaline water.

The cement strength improver can be used in any suitable embodiment. Examples of such an embodiment include an embodiment in which the cement strength improver is blended with cement as it is and used, and an embodiment in which the cement strength improver is blended with other components and used in cement. Can be mentioned.

The amount of the cement strength improving agent used is preferably 0.001% by mass to 0.5% by mass, more preferably 0.002% by mass to 0.1% by mass, still more preferably, with respect to the cement. Is 0.003% by mass to 0.05% by mass, particularly preferably 0.004% by mass to 0.02% by mass, and most preferably 0.005% by mass to 0.01% by mass. By adjusting the amount of the cement strength improving agent used within the above range, the strength of the cured product of the cement composition can be significantly improved over a long period of time.

≪2. One Embodiment of Cement Additives ≫
One embodiment of the cement additive has the cement strength improver and at least one selected from the group consisting of the following A component, B component, and C component.
Component A: A compound having a structure in which 5 mol or more of alkylene oxide is added to 1 mol of alcohol.
Component B: Alkanolamine compound.
Component C: At least one selected from the group consisting of oxycarboxylic acid or a salt thereof, keto acid or a salt thereof, sugar, and sugar alcohol.

The cement strength improver may be only one kind or two or more kinds.

The A component may be only one kind or two or more kinds. The B component may be only one kind or two or more kinds. The C component may be only one kind or two or more kinds.

The cement additive has the above-mentioned cement strength improver and at least one selected from the group consisting of the A component, the B component, and the C component, whereby the strength of the cured product of the cement composition is remarkably increased over a long period of time. It exerts the effect that it can be improved.

Specifically, the effect of improving the long-term strength of the cured product of the cement composition developed by the cement additive is
(I) The effect expected from the sum of the long-term strength improving effect of the cured product of the cement composition caused only by the cement strength improving agent and the long-term strength improving effect of the cured product of the cement composition caused only by the component A. In comparison, it shows a significantly higher synergistic effect,
(Ii) The effect expected from the sum of the long-term strength improving effect of the cured product of the cement composition caused only by the cement strength improving agent and the long-term strength improving effect of the cured product of the cement composition caused only by the B component. In comparison, it shows a significantly higher synergistic effect,
(Iii) The effect expected from the sum of the long-term strength improving effect of the cured product of the cement composition caused only by the cement strength improving agent and the long-term strength improving effect of the cured product of the cement composition caused only by the C component. Compared with, it shows a remarkably high synergistic effect.

The content ratio of the total amount of the cement strength improver and at least one selected from the group consisting of A component, B component, and C component in the cement additive is preferably 50% by mass to 100% by mass. It is more preferably 70% by mass to 100% by mass, further preferably 90% by mass to 100% by mass, particularly preferably 95% by mass to 100% by mass, and most preferably substantially 100% by mass. %. That is, most preferably, the cement additive of the present invention comprises the above-mentioned cement strength improving agent and at least one selected from the group consisting of the A component, the B component, and the C component.

The content ratio of the above-mentioned cement strength improver in the additive for cement is preferably 0.001% by mass to 0.5% by mass, and more preferably 0.002% by mass to 0.1% by mass with respect to the cement. %, More preferably 0.002% by mass to 0.05% by mass, particularly preferably 0.003% by mass to 0.02% by mass, and most preferably 0.005% by mass to 0.01. It is mass%. By adjusting the content ratio of the cement strength improver in the cement additive 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 content ratio of the component A in the additive for cement is preferably 0.001% by mass to 0.5% by mass, and more preferably 0.002% by mass to 0.1% by mass with respect to the cement. It is more preferably 0.002% by mass to 0.05% by mass, particularly preferably 0.005% by mass to 0.02% by mass, and most preferably 0.01% by mass to 0.02% by mass. be. By adjusting the content ratio of the component A in the cement additive 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 content ratio of the B component in the additive for cement is preferably 0.001% by mass to 0.5% by mass, and more preferably 0.002% by mass to 0.1% by mass with respect to the cement. It is more preferably 0.002% by mass to 0.05% by mass, particularly preferably 0.005% by mass to 0.02% by mass, and most preferably 0.01% by mass to 0.02% by mass. be. By adjusting the content ratio of the B component in the cement additive 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 content ratio of the C component in the additive for cement is preferably 0.001% by mass to 0.5% by mass, and more preferably 0.002% by mass to 0.3% by mass with respect to the cement. It is more preferably 0.003% by mass to 0.1% by mass, particularly preferably 0.005% by mass to 0.05% by mass, and most preferably 0.01% by mass to 0.05% by mass. be. By adjusting the content ratio of the C component in the cement additive within the above range, the strength of the cured product of the cement composition can be significantly improved over a long period of time.

Ratio ratio of at least one selected from the group consisting of A component, B component, and C component to the cement strength improving agent in the cement additive (selected from the group consisting of A component, B component, and C component). At least one kind / the above-mentioned cement strength improver) is preferably 0.05 to 20, more preferably 0.1 to 15, still more preferably 0.1 to 10, and particularly preferably 0. It is 1 to 5, and most preferably 0.2 to 1. Ratio ratio of at least one selected from the group consisting of A component, B component, and C component to the cement strength improving agent in the cement additive (selected from the group consisting of A component, B component, and C component). By adjusting at least one of these / the cement strength improver) 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 additives include any suitable cement strength improver and at least one selected from the group consisting of A component, B component, and C component, as long as the effects of the present invention are not impaired. May contain the components of.

<2-1. A component>
The component A is a compound having a structure in which 5 mol or more of alkylene oxide is added to 1 mol of alcohol.

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, and more preferably 2 carbon atoms, in that the effects of the present invention can be more exhibited. It is an alkylene oxide having 6 to 6, 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 or propylene oxide). Further, the alkylene oxide may be only one kind or two or more kinds.

The number of moles of alkylene oxide added to 1 mol of alcohol is preferably 10 mol or more, more preferably 20 mol or more, still more preferably 30 mol or more, still more preferably 40 mol or more, as a lower limit. More preferably 50 mol or more, further preferably 100 mol or more, particularly preferably 500 mol or more, most preferably 1000 mol or more, and as an upper limit value, preferably 100,000 mol or less. It is preferably 50,000 mol or less, more preferably 40,000 mol or less, further preferably 30,000 mol or less, further preferably 20,000 mol or less, still more preferably 10,000 mol or less, and particularly preferably 7,000 mol or less. Most preferably, it is 5000 mol or less. By adjusting the number of moles of alkylene oxide added to 1 mole of alcohol 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 weight average molecular weight of the compound as the component A is preferably 4000 or more, more preferably 5000 or more, further preferably 10000 or more, particularly preferably 20000 or more, and most preferably 100,000 as the lower limit value. As described above, the upper limit value is preferably 10,000,000 or less, more preferably 5,000,000 or less, further preferably 1,000,000 or less, particularly preferably 700,000 or less, and most preferably 300,000 or less. By adjusting the weight average molecular weight of the compound as the component A 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 method for measuring the weight average molecular weight will be described later.

Examples of the alcohol include methanol, ethanol, propanol and butanol as the monohydric alcohol, and the polyhydric alcohol may be a compound having two or more hydroxyl groups, and may be a low molecular weight compound or a polymer. Any suitable polyhydric alcohol may be adopted as long as the effect of the present invention is not impaired. The polyhydric alcohol is preferably a divalent to 500-valent alcohol, more preferably a divalent to 100-valent alcohol, and further preferably a trivalent to 50-valent alcohol. Examples of such polyhydric alcohols include ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, neopentyl glycol, pentandiol, butanediol, glycerin, and sorbitol.

Examples of the 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, and 2-methyl-3-bu. Examples include tenyl alcohol. These may be polymerized alone or copolymerized with other polymerizable monomers.

The compound as the component A may have any suitable functional group as long as the effect of the present invention is not impaired. However, the compound as the component A preferably does not have a carboxyl group in that the effect of the present invention can be sufficiently exhibited.

As a method for synthesizing the compound as the component A, any suitable method such as a known method can be adopted as long as the effect of the present invention is not impaired. Examples of such a method include a method of polymerizing a monomer having a hydroxyl group and then adding an alkylene oxide, a method of first adding an alkylene oxide to a monomer having a hydroxyl group, and then polymerizing.

Specific examples of the compound as the component A include polyethylene glycol, a copolymer having a structural unit derived from an alkylene oxide adduct of methacrylic acid, an alkylene oxide adduct of sorbitol, and 3-methyl-3-butenyl. Examples thereof include a copolymer having a structural unit derived from an alkylene oxide adduct of an alcohol, an alkylene oxide adduct to an active hydrogen bonded to an amino group of polyethyleneimine, and the like. Here, the "alkylene oxide adduct to the active hydrogen bonded to the amino group of polyethyleneimine" means that alkylene oxide (ethylene oxide or the like) is arbitrarily appropriate for the active hydrogen bonded to the amino group of polyethyleneimine. An adduct added with a large number of added moles.

When the compound as component A is a copolymer having a structural unit derived from an alkylene oxide adduct of 3-methyl-3-butenyl alcohol, the copolymer is carboxyl in that the effect of the present invention can be more exhibited. It is preferable that the group or a salt thereof (such as an alkali metal salt or an alkaline earth metal salt) is not contained.

<2-2. B component>
As the alkanolamine compound, any suitable alkanolamine compound may be adopted as long as the effects of the present invention are not impaired. Examples of such an alkanolamine compound include a low molecular weight alkanolamine compound and a high molecular weight alkanolamine compound.

Examples of the low molecular weight alkanolamine compound include monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, methylethanolamine, methylisopropanolamine, methyldiethanolamine, and methyldiisopropanolamine. Diethanolisopropanolamine, diisopropanolethanolamine, tetrahydroxyethylethylenediamine, N, N-bis (2-hydroxyethyl) 2-propanolamine, N, N-bis (2-hydroxypropyl) -N- (hydroxyethyl) amine, N, N-bis (2-hydroxyethyl) -N- (2-hydroxypropyl) amine, N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine, tris (2-hydroxybutyl) amine, And so on. Among these, preferred examples of the low-molecular-weight alkanolamine compound include triisopropanolamine, N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine, and diisopropanolethanolamine. Examples of other small molecule alkanolamine compounds include monomers having a skeleton of triisopropanolamine.

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

<2-3. C component>
The C component is at least one selected from oxycarboxylic acid or a salt thereof, keto acid or a salt thereof, sugar, and sugar alcohol.

As the oxycarboxylic acid, any suitable oxycarboxylic acid may be adopted. Examples of such oxycarboxylic acids include gluconic acid, tartrate acid, citric acid, malic acid, glucoheptonic acid, alabonic acid and the like, and gluconic acid is preferable in that the effects of the present invention can be more exhibited. It is at least one selected from tartrate acid, citric acid, and malic acid.

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

As the keto acid, any suitable keto acid may be adopted. Examples of such keto acids include pyruvic acid, oxoglutaric acid, and the like, and pyruvic acid is preferable in that the effects of the present invention can be more exhibited.

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

As the sugar, any suitable sugar may be adopted. Examples of such sugars include monosaccharides such as glucose, fructose, galactose, mannose, xylose, arabinose, ribose and isomerized sugars; disaccharides such as maltose, shoe cloth and lactose; trisaccharides such as raffinose; dextrin and the like. Oligosaccharides; and the like, and glucose is preferable in that the effects of the present invention can be more exhibited.

As the sugar alcohol, any suitable sugar alcohol may be adopted. Such sugar alcohols are preferably sorbitol, mannitol, xylitol, and galactitol in that the effects of the present invention can be more exhibited.

≪3. Another Embodiment of Cement Additives »
As another embodiment of the cement additive capable of exhibiting the effect of the present invention, a polysaccharide (component X) having a gel-forming ability to gel in alkaline water, and the following components A, B, and C are described below. It has at least one species selected from the group consisting of.
Component A: A compound having a structure in which 5 mol or more of alkylene oxide is added to 1 mol of alcohol.
Component B: Alkanolamine compound.
Component C: At least one selected from the group consisting of oxycarboxylic acid or a salt thereof, keto acid or a salt thereof, sugar, and sugar alcohol.

The X component may be only one kind or two or more kinds.

The A component may be only one kind or two or more kinds. The B component may be only one kind or two or more kinds. The C component may be only one kind or two or more kinds.

The cement additive has at least one selected from the group consisting of the X component and the A component, the B component, and the C component, so that the strength of the cured product of the cement composition can be significantly improved over a long period of time. The effect is expressed.

Specifically, the effect of improving the long-term strength of the cured product of the cement composition developed by the cement additive is
(I) Compared with the effect expected from the sum of the effect of improving the long-term strength of the cured product of the cement composition caused only by the component X and the effect of improving the long-term strength of the cured product of the cement composition caused only by the component A. Remarkably high synergistic effect,
(Ii) Compared with the effect expected from the sum of the long-term strength improving effect of the cured product of the cement composition caused only by the X component and the long-term strength improving effect of the cured product of the cement composition caused only by the B component. Remarkably high synergistic effect,
(Iii) Compared with the effect expected from the sum of the effect of improving the long-term strength of the cured product of the cement composition caused only by the component X and the effect of improving the long-term strength of the cured product of the cement composition caused only by the component C. , Shows a remarkably high synergistic effect.

The content ratio of the total amount of the X component and at least one selected from the group consisting of the A component, the B component, and the C component in the additive for cement is preferably 50% by mass to 100% by mass. It is more preferably 70% by mass to 100% by mass, further preferably 90% by mass to 100% by mass, particularly preferably 95% by mass to 100% by mass, and most preferably substantially 100% by mass. .. That is, most preferably, the cement additive of the present invention comprises at least one selected from the group consisting of the X component, the A component, the B component, and the C component.

The content ratio of the X component in the additive for cement is preferably 0.001% by mass to 0.5% by mass, and more preferably 0.002% by mass to 0.1% by mass with respect to the cement. It is more preferably 0.002% by mass to 0.05% by mass, particularly preferably 0.003% by mass to 0.02% by mass, and most preferably 0.005% by mass to 0.01% by mass. be. By adjusting the content ratio of the X component in the cement additive 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 content ratio of the component A in the additive for cement is preferably 0.001% by mass to 0.5% by mass, and more preferably 0.002% by mass to 0.1% by mass with respect to the cement. It is more preferably 0.002% by mass to 0.05% by mass, particularly preferably 0.005% by mass to 0.02% by mass, and most preferably 0.01% by mass to 0.02% by mass. be. By adjusting the content ratio of the component A in the cement additive 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 content ratio of the B component in the additive for cement is preferably 0.001% by mass to 0.5% by mass, and more preferably 0.002% by mass to 0.1% by mass with respect to the cement. It is more preferably 0.002% by mass to 0.05% by mass, particularly preferably 0.005% by mass to 0.02% by mass, and most preferably 0.01% by mass to 0.02% by mass. be. By adjusting the content ratio of the B component in the cement additive 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 content ratio of the C component in the additive for cement is preferably 0.001% by mass to 0.5% by mass, and more preferably 0.002% by mass to 0.3% by mass with respect to the cement. It is more preferably 0.003% by mass to 0.1% by mass, particularly preferably 0.005% by mass to 0.05% by mass, and most preferably 0.01% by mass to 0.05% by mass. be. By adjusting the content ratio of the C component in the cement additive within the above range, the strength of the cured product of the cement composition can be significantly improved over a long period of time.

Ratio ratio of at least one selected from the group consisting of A component, B component, and C component to X component in the cement additive (at least 1 selected from the group consisting of A component, B component, and C component). The seed / X component) is preferably 0.05 to 20, more preferably 0.1 to 15, still more preferably 0.1 to 10, and particularly preferably 0.1 to 5. Most preferably, it is 0.2 to 1. Ratio ratio of at least one selected from the group consisting of A component, B component, and C component to X component in the cement additive (at least 1 selected from the group consisting of A component, B component, and C component). By adjusting the seed / X component) within the above range, the strength of the cured product of the cement composition can be significantly improved over a long period of time.

In the cement additive, any appropriate component other than the X component and at least one selected from the group consisting of the A component, the B component, and the C component can be contained as long as the effect of the present invention is not impaired. It may be included.

<3-1. X component>
The X component is a polysaccharide having a gel-forming ability to gel in alkaline water.

Examples of such an X component include at least one selected from the group consisting of alginic acid or a salt thereof, an alginic acid ester, and glucomannan.

Preferred examples of alginic acid or a salt thereof include sodium alginate. Examples of the alginic acid ester include propylene glycol alginate and lauroyl alginate, and propylene glycol alginate is preferable. Alginic acid or a salt thereof, alginic acid ester, is typically a polysaccharide having a gel-forming ability to gel via calcium ions.

Glucomannan is a polysaccharide capable of gelling in alkaline water.

<3-2. A component, B component, C component>
Regarding the A component, B component, and C component, the above-mentioned << 2. <2-1. In the item of "One Embodiment of Cement Additives". Explanation of component A in the item of component A, <2-2. Explanation of B component in the item of B component>, <2-3. The explanation about the C component in the item of C component> can be used as it is.

≪4. Cement composition ≫
The cement composition comprises at least cement, water, and a polysaccharide capable of gelling in alkaline water. The polysaccharide having a gel-forming ability to gel in alkaline water may be the above-mentioned cement strength improving agent.

The cement composition may further contain at least one selected from the group consisting of the above A component, B component, and C component. For the A component, the B component, and the C component, the description of the A component, the B component, and the C component in the above-mentioned << Cement additive >> can be used as it is.

When the cement composition has a polysaccharide having a gel-forming ability to gel in alkaline water and at least one selected from the group consisting of the above A component, B component, and C component, the blending of these components is performed. , A polysaccharide having a gel-forming ability to gel in alkaline water, and at least one selected from the group consisting of the above A component, B component, and C component are blended in the form of an additive for cement. However, the polysaccharide having a gel-forming ability to gel in alkaline water and at least one selected from the group consisting of the above A component, B component, and C component are the additives for cement. It may be a form in which it is blended without taking a form (for example, each is blended separately).

The cement composition preferably contains an aggregate and a water reducing agent in addition to a polysaccharide having a gel-forming ability to gel in alkaline water and at least one selected from the above-mentioned components A, B and C.

The cement may be of only one type or of two or more types. As the cement, any suitable cement may be adopted. Examples of such cement include Portoland cement (ordinary, early-strength, ultra-fast-strength, moderate heat-resistant, sulfate-resistant and each low-alkali form), various mixed cements (blast furnace cement, silica cement, fly ash cement), and the like. White Portoland Cement, Alumina Cement, Ultra Fast Hard Cement (1 Clinker Fast Hard Cement, 2 Clinker Fast Hard Cement, Magnesium Phosphate Cement), Grout Cement, Oil Well Cement, Low Heat Cement (Low Heat Heat Type High Furnace Cement, Fly Ash Mixed Low) Heat-generating blast furnace cement, belite-rich cement), ultra-high-strength cement, cement-based solidifying material, and eco-cement (cement manufactured from one or more of municipal waste incineration ash and sewage sludge incineration ash) can be mentioned.

The cement composition may contain fine powder such as blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica powder, limestone powder and gypsum.

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

The aggregate may be only one kind or two or more kinds. As the aggregate, any suitable aggregate such as fine aggregate (sand or the like) or coarse aggregate (crushed stone or the like) can be adopted. Examples of such aggregates include gravel, crushed stone, granulated slag, and recycled aggregate. In addition, examples of such aggregates include refractory aggregates such as silica stone, clay, zircon, high alumina, silicon carbide, graphite, chromium, chromog, and magnesia.

The water reducing agent may be only one kind or two or more kinds. Preferred examples of the water reducing agent include a polycarboxylic acid-based dispersant having a polyoxyalkylene chain and a carboxyl group in the molecule, and a sulfonic acid-based dispersant having a sulfonic acid group in the molecule.

As the polycarboxylic acid-based dispersant, for example, a polyalkylene glycol mono (meth) acrylic acid ester-based monomer having a polyoxyalkylene chain to which an alkylene oxide having 2 to 18 carbon atoms is added in an average number of moles of 2 to 300 is added. A copolymer obtained by copolymerizing a monomer component containing (meth) acrylic acid-based monomer as an essential component; an alkylene oxide having 2 to 18 carbon atoms was added in an average number of moles of 2 to 300. Contains three types of monomers, a polyalkylene glycol mono (meth) acrylic acid ester-based monomer having a polyoxyalkylene chain, a (meth) acrylic acid-based monomer, and a (meth) acrylic acid alkyl ester as essential components. Polymer obtained by copolymerizing a monomer component; a polyalkylene glycol mono (meth) acrylic acid ester having a polyoxyalkylene chain to which an alkylene oxide having 2 to 18 carbon atoms is added in an average number of moles of 2 to 300. System monomer and (meth) acrylic acid system monomer and (meth) allylsulfonic acid (salt) (or either vinylsulfonic acid (salt) or p- (meth) allyloxybenzenesulfonic acid (salt)) A copolymer obtained by copolymerizing a monomer component containing the above three types of monomers as essential components; a polyoxyalkylene having 2 to 300 alkylene oxides having 2 to 18 carbon atoms added in an average number of moles. Contains three types of monomers, a polyalkylene glycol mono (meth) acrylic acid ester-based monomer having a chain, a (meth) acrylic acid-based monomer, and a (meth) allylsulfonic acid (salt) as essential components. A copolymer obtained by copolymerizing a monomer component and further graft-polymerizing (meth) acrylamide and / or 2- (meth) acrylamide-2-methylpropanesulfonic acid; a copolymer having 2 to 18 carbon atoms. A polyalkylene glycol mono (meth) acrylic acid ester-based monomer having a polyoxyalkylene chain to which alkylene oxide is added by an average number of moles of 2 to 300 and an alkylene oxide having 2 to 18 carbon atoms are added by an average number of moles of 2 to Polyalkylene glycol mono (meth) allyl ether-based monomer, (meth) acrylic acid-based monomer and (meth) allylsulfonic acid (salt) (or p- (meth) allyl having 300 added polyoxyalkylene chains. A copolymer obtained by copolymerizing a monomer component containing four kinds of monomers with oxybenzenesulfonic acid (salt) as an essential component; an alkylene oxide having 2 to 18 carbon atoms in an average number of moles added. Polyoxyacrylic acid with 2 to 300 added A copolymer obtained by copolymerizing a monomer component containing a polyalkylene glycol mono (meth) allyl ether-based monomer having a len chain and a maleic acid-based monomer as essential components; A polyalkylene glycol mono (meth) allyl ether-based monomer having a polyoxyalkylene chain to which 2 to 300 alkylene oxides are added in an average number of moles and a polyalkylene glycol ester-based monomer of maleic acid are essential components. Copolymer obtained by copolymerizing a monomer component containing; An esterification reaction product of a copolymer of a system monomer and maleic anhydride and a polyoxyalkylene derivative having a hydroxyl group at the terminal; a poly having 2 to 300 alkylene oxides having 2 to 18 carbon atoms added in an average number of moles. A copolymer obtained by copolymerizing a polyalkylene glycol mono (3-methyl-3-butenyl) ether-based monomer having an oxyalkylene chain and a monomer component containing a (meth) acrylic acid-based monomer as an essential component. Polymer: Polyalkylene glycol mono (3-methyl-3-butenyl) ether-based monomer and maleic acid-based polymer having a polyoxyalkylene chain to which an alkylene oxide having 2 to 18 carbon atoms is added in an average number of moles. Examples thereof include a copolymer obtained by copolymerizing a monomer component containing a monomer as an essential component.

Examples of the sulfonic acid-based dispersant include polyalkylaryl sulfonate-based sulfonic acid-based dispersants such as naphthalene sulfonic acid formaldehyde condensate, methylnaphthalene sulfonic acid formaldehyde condensate, and anthracene sulfonic acid formaldehyde condensate; melamine sulfonic acid. Melamine formalin resin sulfonate-based sulfonic acid-based dispersants such as formaldehyde condensates; aromatic aminosulfonate-based sulfonic acid-based dispersants such as aminoaryl sulfonic acid-phenol-formaldehyde condensates; lignin sulfonates, Examples thereof include a lignin sulfonate-based sulfonic acid-based dispersant such as a modified lignin sulfonate; a polystyrene sulfonate-based sulfonic acid-based dispersant;

When the cement composition contains a water reducing agent, any appropriate content ratio may be adopted as the content ratio of the water reducing agent in the cement composition, depending on the purpose. Such a content ratio is preferably 0.01% by mass to 10% by mass, more preferably 0.02% by mass to 5% by mass, and further preferably 0.05% by mass with respect to the cement. It is about 3% by mass, particularly preferably 0.07% by mass to 1% by mass, and most preferably 0.1% by mass to 0.7% by mass. By adjusting the content ratio of the water reducing agent in the cement composition within the above range, various preferable effects such as reduction of unit water amount, increase of strength, and improvement of durability are brought about.

The cement composition may contain any suitable additional ingredients. Such additional components may be only one kind or two or more kinds. Such additional components include, for example, water-soluble polymer substances, polymer emulsions, fast-strengthening agents / accelerators, AE agents, defoaming agents, crack reducing agents, surfactants, waterproofing materials, rust preventives, and swelling agents. Examples thereof include materials, cement wetting agents, thickening agents, separation reducing agents, flocculants, drying shrinkage reducing agents, strength enhancing agents, self-leveling agents, coloring agents, antifungal agents and the like.

Examples of the water-soluble polymer substance include nonionic cellulose ethers such as methyl cellulose, ethyl cellulose and carboxymethyl cellulose; polysaccharides produced by microbial fermentation such as yeast glucan, xanthan gum and β-1.3 glucan; polyethylene glycol. Etc., Polyoxyalkylene glycols; polyacrylamide; and the like.

Examples of the polymer emulsion include copolymers of various vinyl monomers such as alkyl (meth) acrylate.

Examples of the fast-strengthening agent / accelerator include 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;

Examples of the AE agent include resin soap, saturated or unsaturated fatty acids, sodium hydroxystearate, lauryl sulfate, ABS (alkylbenzene sulfonic acid), alkanesulfonate, polyoxyethylene alkyl (phenyl) ether, and polyoxyethylene alkyl (phenyl). Examples thereof include ether sulfate ester or a salt thereof, polyoxyethylene alkyl (phenyl) ether phosphate ester or a salt thereof, protein material, alkenyl sulfosuccinic acid, and α-olefin sulfonate.

Examples of the defoaming agent include oxyalkylene-based defoaming agent, mineral oil-based defoaming agent, oil-based defoaming agent, fatty acid-based defoaming agent, fatty acid ester-based defoaming agent, alcohol-based defoaming agent, and amide-based defoaming agent. Examples thereof include agents, phosphate ester-based defoamers, metal soap-based defoamers, and silicone-based defoamers. Examples of the oxyalkylene-based defoaming agent include 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 salts; polyoxyalkylene alkyl phosphate esters; polyoxypropylene polyoxyethylene laurylamine (addition of 1 to 20 mol of propylene oxide, addition of 1 to 20 mol of ethylene oxide, etc.) and alkylene oxide are added. Examples thereof include polyoxyalkylene alkyl amines such as amines derived from fatty acids obtained from hardened beef fat (addition of 1 to 20 mol of propylene oxide, adduct of 1 to 20 mol of ethylene oxide, etc.); polyoxyalkylene amide;

Examples of the crack reducing agent include polyoxyalkyl ethers.

Examples of the surfactant include various anionic surfactants; various cationic surfactants such as alkyltrimethylammonium chloride; various nonionic surfactants; and various amphoteric surfactants.

Examples of the waterproofing agent include fatty acids (salts), fatty acid esters, fats and oils, silicones, paraffins, asphalts, and waxes.

Examples of the rust preventive include nitrite, phosphate and zinc oxide.

Examples of the expanding material include an ettringite-based expanding material and a coal-based expanding material.

The types, combinations, blending amounts, etc. of the additional components can be appropriately set according to the purpose.

The content ratio of the additional component in the cement composition is preferably 0% by mass to 50% by mass, more preferably 0% by mass to 10% by mass, and further preferably 0% by mass to 1 as a solid content ratio. It is by mass, and particularly preferably 0% by mass to 0.1% by mass.

The cement composition may be effective for ready-mixed concrete, concrete for secondary concrete products, concrete for centrifugal molding, concrete for vibration compaction, steam curing concrete, sprayed concrete and the like.

Cement compositions include 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-leveling material, etc. It can also be effective for mortar and concrete that require high fluidity.

The cement composition may be prepared by blending the constituent components by any appropriate method. For example, a method of kneading the constituents in a mixer may be mentioned.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples. Unless otherwise specified, the term "parts" means parts by mass, and the term "%" means% by mass.

<Weight average molecular weight analysis conditions>
-Column used: Tosoh Corporation, TSKguardcolumnα + TSKgelα-5000 + TSKgelα-4000 + TSKgelα-3000 were connected and used one by one.
-Eluent: Sodium dihydrogen phosphate, 2H ₂ O: 62.4 g, disodium hydrogen phosphate, 12H ₂ O: 143.3 g in a solution of ion-exchanged water: 7794.3 g, acetonitrile: 2000 g. Was used as a mixed solution.
-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 cell capacity, 670 nm wavelength.
-Standard sample: Polyethylene glycol SE-8 (Mw = l07000) manufactured by Tosoh Corporation was used, the dn / dC was 0.135 ml / g, and the refractive index of the eluent was 1.333 to determine the device constant.
-Driving amount Standard sample: 100 μL of the solution dissolved in the above eluent was injected so that the polymer concentration was 0.2 vol%.
Sample: 100 μL of the solution dissolved in the above eluent was injected so that the polymer concentration became 1.0 vol%.
・ Flow velocity: 0.8 ml / min
-Column temperature: 40 ° C

<Concrete test>
(Manufacturing of cement composition)
Ordinary Portoland cement (manufactured by Pacific Cement Co., Ltd.) as cement, land sand from Oigawa water system as fine aggregate, crushed stone from Qinghai as coarse aggregate, 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 , water reducing agent: amount shown in Table 2, cement strength improver or cement additive or comparative additive: amount shown in Table 2, fine A cement composition was prepared with a composition of aggregate ratio (fine aggregate / fine coarse aggregate + coarse aggregate) (volume ratio): 47% and water / cement ratio (mass ratio) = 0.45.
The materials used for the test, the forced kneading mixer, and the measuring instruments were adjusted under the above test temperature atmosphere so that the temperature of the cement composition became the test temperature of 20 ° C., and the kneading and each measurement were performed as described above. The test was performed in a test temperature atmosphere.
Further, in order to avoid the influence of air bubbles in the cement composition on the fluidity of the cement composition, an oxyalkylene defoaming agent is used as necessary so that the amount of air becomes 1.0 ± 0.5%. Adjusted to.
A cement composition was produced under the above conditions with a kneading time of 90 seconds using a forced kneading mixer, and the slump value, the flow value, and the amount of air were measured. The slump value, flow value, and air volume were measured in accordance with Japanese Industrial Standards (JIS-A-1101, 1128). The amount of the water reducing agent added was such that the flow value was 37.5 to 42.5 cm.

(Measurement of compressive strength)
After kneading, the flow value and the amount of air were measured, a sample for a compressive strength test was prepared, and the compressive strength after 28 days was measured under the following conditions.
Specimen preparation: 100 mm x 200 mm
Specimen curing (28 days): Temperature approx. 20 ° C, humidity 60%, constant temperature and humidity constant air curing for 24 hours, then curing in water for 27 days Specimen polishing: Specimen surface polishing (using specimen polishing finishing machine)
Compressive strength measurement: Automatic compressive strength measuring instrument (Maekawa Mfg. Co., Ltd.)

[Production Example 1]: Production of the copolymer (1) Ions in a glass reaction vessel equipped with a Dimroth condenser, a stirrer with a stirring blade and a stirring seal made of Teflon (registered trademark), a nitrogen introduction tube, and a temperature sensor. 80.0 parts of the exchanged 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 methoxypolyethylene glycol monomethacrylic acid ester (average number of moles of ethylene oxide added), 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 at the same time, 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 keeping the temperature at 70 ° C. for 1 hour after the dropping was completed. Then, it was neutralized with an aqueous solution of sodium hydroxide to obtain an aqueous solution of the copolymer (1) having a weight average molecular weight of 100,000.

[Example 1]
Sodium alginate (manufactured by Wako Pure Chemical Industries, Ltd.) was used as the cement strength improver (1). The results are shown in Table 1.

[Example 2]
Glucomannan (trade name "Propol A", manufactured by Shimizu Chemical Co., Ltd.) was used as the cement strength improver (2). The results are shown in Table 1.

[Example 3]
Sodium alginate (manufactured by Wako Pure Chemical Industries, Ltd.) and PEG200,000 (polyethylene glycol, manufactured by Aldrich, weight average molecular weight = 200,000) were blended in a mass ratio of 1: 1 to prepare an additive (1) for cement. The results are shown in Table 1.

[Example 4]
20 mol of ethylene oxide added to 1 mol of active hydrogen of amino group of sodium alginate (manufactured by Wako Pure Chemical Industries, Ltd.) and ESP (weight average molecular weight = 23000, polyethyleneimine (weight average molecular weight = 600), manufactured by Nippon Catalyst) ) Was compounded at a mass ratio of 1: 1 to prepare an additive for cement (2). The results are shown in Table 1.

[Example 5]
Sodium alginate (manufactured by Wako Pure Chemical Industries, Ltd.) and EDIPA (hydroxyethyldiisopropanolamine, manufactured by Aldrich) were blended at a mass ratio of 1: 1 to prepare an additive for cement (3). The results are shown in Table 1.

[Example 6]
Sodium alginate (manufactured by Wako Pure Chemical Industries, Ltd.) and TIPA (triisopropanolamine, manufactured by Wako Pure Chemical Industries, Ltd.) were blended at a mass ratio of 1: 1 to prepare an additive for cement (4). The results are shown in Table 1.

[Example 7]
Sodium alginate (manufactured by Wako Pure Chemical Industries, Ltd.) and sorbitol (manufactured by Wako Pure Chemical Industries, Ltd.) were blended at a mass ratio of 1: 5 to prepare an additive for cement (5). The results are shown in Table 1.

[Example 8]
Sodium alginate (manufactured by Wako Pure Chemical Industries, Ltd.) and sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) were blended at a mass ratio of 1: 5 to prepare an additive for cement (6). The results are shown in Table 1.

[Comparative Example 1]
PEG 200,000 (polyethylene glycol, manufactured by Aldrich, weight average molecular weight = 200,000) was used as the comparative additive (C1). The results are shown in Table 1.

[Comparative Example 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, manufactured by Nippon Shokubai) was used as a comparative additive (C2). .. The results are shown in Table 1.

[Comparative Example 3]
EDIPA (hydroxyethyldiisopropanolamine, manufactured by Aldrich) was used as a comparative additive (C3). The results are shown in Table 1.

[Comparative Example 4]
TIPA (triisopropanolamine, manufactured by Wako Pure Chemical Industries, Ltd.) was used as a comparative additive (C4). The results are shown in Table 1.

[Comparative Example 5]
Sorbitol (manufactured by Wako Pure Chemical Industries, Ltd.) was used as a comparative additive (C5). The results are shown in Table 1.

[Comparative Example 6]
Sodium gluconate (manufactured by Wako Pure Chemical Industries, Ltd.) was used as a comparative additive (C6). The results are shown in Table 1.

[Example 9]
The cement composition (1) was prepared and compressed by using the copolymer (1) obtained in Production Example 1 and the cement strength improving agent (1) obtained in Example 1 in the blending amounts shown in Table 2. The intensity was measured. The results are shown in Table 2.

[Example 10]
The cement composition (2) was prepared and compressed by using the copolymer (1) obtained in Production Example 1 and the cement strength improving agent (1) obtained in Example 1 in the blending amounts shown in Table 2. The intensity was measured. The results are shown in Table 2.

[Example 11]
The cement composition (3) was prepared and compressed by using the copolymer (1) obtained in Production Example 1 and the cement strength improving agent (1) obtained in Example 1 in the blending amounts shown in Table 2. The intensity was measured. The results are shown in Table 2.

[Example 12]
The cement composition (4) was prepared and compressed by using the copolymer (1) obtained in Production Example 1 and the cement strength improving agent (2) obtained in Example 2 in the blending amounts shown in Table 2. The intensity was measured. The results are shown in Table 2.

[Example 13]
The cement composition (5) is adjusted by using the copolymer (1) obtained in Production Example 1 and the cement additive (1) obtained in Example 3 in the blending amounts shown in Table 2. And the compressive strength was measured. The results are shown in Table 2.
In preparing the cement composition (5), instead of adding and using the cement additive (1) obtained in Example 3, sodium alginate and PEG 200,000 were blended in the amounts shown in Table 2. Similar results were obtained when each was added independently and used.

[Example 14]
The cement composition (6) is adjusted by using the copolymer (1) obtained in Production Example 1 and the cement additive (2) obtained in Example 4 in the blending amounts shown in Table 2. And the compressive strength was measured. The results are shown in Table 2.
In preparing the cement composition (6), instead of adding and using the cement additive (2) obtained in Example 4, sodium alginate and ESP are blended in the amounts shown in Table 2, respectively. Similar results were obtained when used independently.

[Example 15]
The cement composition (7) is adjusted by using the copolymer (1) obtained in Production Example 1 and the cement additive (3) obtained in Example 5 in the blending amounts shown in Table 2. And the compressive strength was measured. The results are shown in Table 2.
In preparing the cement composition (7), instead of adding and using the cement additive (3) obtained in Example 5, sodium alginate and EDIPA were added in the amounts shown in Table 2, respectively. Similar results were obtained when used independently.

[Example 16]
The cement composition (8) is adjusted by using the copolymer (1) obtained in Production Example 1 and the cement additive (4) obtained in Example 6 in the blending amounts shown in Table 2. And the compressive strength was measured. The results are shown in Table 2.
In preparing the cement composition (8), instead of adding and using the cement additive (4) obtained in Example 6, sodium alginate and TIPA were blended in the amounts shown in Table 2, respectively. Similar results were obtained when used independently.

[Example 17]
The cement composition (9) is adjusted by using the copolymer (1) obtained in Production Example 1 and the cement additive (5) obtained in Example 7 in the blending amounts shown in Table 2. And the compressive strength was measured. The results are shown in Table 2.
In preparing the cement composition (9), instead of adding and using the cement additive (5) obtained in Example 7, sodium alginate and sorbitol were added in the amounts shown in Table 2, respectively. Similar results were obtained when used independently.

[Example 18]
The cement composition (10) was prepared by using the copolymer (1) obtained in Production Example 1 and the cement additive (6) obtained in Example 8 in the blending amounts shown in Table 2. And the compressive strength was measured. The results are shown in Table 2.
In preparing the cement composition (10), instead of adding and using the cement additive (6) obtained in Example 8, sodium alginate and sodium gluconate were added to the blending amounts shown in Table 2. Similar results were obtained even when they were added independently and used.

[Comparative Example 7]
The copolymer (1) obtained in Production Example 1 was used in the blending amounts shown in Table 2 to prepare the cement composition (C1), and the compressive strength was measured. The results are shown in Table 2.

[Comparative Example 8]
Using the copolymer (1) obtained in Production Example 1 and the comparative additive (C1) obtained in Comparative Example 1 in the blending amounts shown in Table 2, the cement composition (C2) was adjusted to obtain compressive strength. Was measured. The results are shown in Table 2.

[Comparative Example 9]
The cement composition (C3) was adjusted by using the copolymer (1) obtained in Production Example 1 and the comparative additive (C2) obtained in Comparative Example 2 in the blending amounts shown in Table 2 to adjust the compressive strength. Was measured. The results are shown in Table 2.

[Comparative Example 10]
The cement composition (C4) was adjusted by using the copolymer (1) obtained in Production Example 1 and the comparative additive (C3) obtained in Comparative Example 3 in the blending amounts shown in Table 2 to adjust the compressive strength. Was measured. The results are shown in Table 2.

[Comparative Example 11]
The cement composition (C5) was adjusted by using the copolymer (1) obtained in Production Example 1 and the comparative additive (C4) obtained in Comparative Example 4 in the blending amounts shown in Table 2 to adjust the compressive strength. Was measured. The results are shown in Table 2.

[Comparative Example 12]
The cement composition (C6) was adjusted by using the copolymer (1) obtained in Production Example 1 and the comparative additive (C5) obtained in Comparative Example 5 in the blending amounts shown in Table 2 to adjust the compressive strength. Was measured. The results are shown in Table 2.

[Comparative Example 13]
The cement composition (C7) was adjusted by using the copolymer (1) obtained in Production Example 1 and the comparative additive (C6) obtained in Comparative Example 6 in the blending amounts shown in Table 2 to adjust the compressive strength. Was measured. The results are shown in Table 2.

In the technical field of the present invention, it is not easy to achieve an improvement of several percent in the 28-day compressive strength of concrete at present, and it is recognized that if an improvement of several percent can be achieved, a significant long-term strength improvement is achieved. ..

As shown in Table 2, none of Comparative Example 7 (cement strength improving agents (1) to (2), cement additives (1) to (6), and comparative additives (C1) to (C6) is added. When the 28-day compression strength of Example) is 100, the cement strength improver (2) obtained in Examples 9 to 11 and Example 2 to which the cement strength improver (1) obtained in Example 1 is added. The 28-day compression strength of Example 12 to which was added was 101 to 105, and a remarkable strength improving effect was observed.

Example 13 is an embodiment in which sodium alginate (0.01% by mass / cement) and PEG200,000 (0.01% by mass / cement) are used in combination, and as shown in Table 2, 28 of Comparative Example 7 The 28-day compressive strength of Example 13 when the daily compressive strength is 100 is 110 (that is, +10). On the other hand, as shown in Table 2, the 28-day compressive strength in Example 11 to which only sodium alginate (0.01% by mass / cement) was added was 105 when the 28-day compressive strength of Comparative Example 7 was 100. (That is, +5), and the 28-day compressive strength in Comparative Example 8 to which only PEG 200,000 (0.01% by mass / cement) is added is 102 (that is, when the 28-day compressive strength of Comparative Example 7 is 100). That is, it is +2), and these simple sums are +7 when the 28-day compressive strength of Comparative Example 7 is 100. Therefore, as shown in Table 2, in Example 13 in which sodium alginate (0.01% by mass / cement) and PEG 200,000 (0.01% by mass / cement) are used in combination, sodium alginate (0.01% by mass / cement) is used. +3 compared to the simple sum of the long-term strength improving effect in Example 11 to which only (/ cement) was added and the long-term strength improving effect in Comparative Example 8 to which only PEG 200,000 (0.01% by mass / cement) was added. The synergistic effect of the above was exhibited, and a remarkable effect of improving the strength was observed.

Example 14 is an embodiment in which sodium alginate (0.01% by mass / cement) and ESP (0.01% by mass / cement) are used in combination, and as shown in Table 2, 28th day of Comparative Example 7. The 28-day compressive strength of Example 14 when the compressive strength is 100 is 111 (that is, +11). On the other hand, as shown in Table 2, the 28-day compressive strength in Example 11 to which only sodium alginate (0.01% by mass / cement) was added was 105 when the 28-day compressive strength of Comparative Example 7 was 100. (Ie, +5), and the 28-day compressive strength in Comparative Example 9 to which only ESP (0.01% by mass / cement) is added is 103 (that is, when the 28-day compressive strength of Comparative Example 7 is 100). , +3), and these simple sums are +8 when the 28-day compressive strength of Comparative Example 7 is 100. Therefore, as shown in Table 2, in Example 14 in which sodium alginate (0.01% by mass / cement) and ESP (0.01% by mass / cement) are used in combination, sodium alginate (0.01% by mass / cement) is used. A synergistic effect of +3 compared to the simple sum of the long-term strength improving effect in Example 11 in which only cement) is added and the long-term strength improving effect in Comparative Example 9 in which only ESP (0.01% by mass / cement) is added. The effect was exhibited, and a remarkable effect of improving strength was observed.

Example 15 is an embodiment in which sodium alginate (0.01% by mass / cement) and EDIPA (0.01% by mass / cement) are used in combination, and as shown in Table 2, 28th day of Comparative Example 7. The 28-day compressive strength of Example 15 when the compressive strength is 100 is 112 (that is, +12). On the other hand, as shown in Table 2, the 28-day compressive strength in Example 11 to which only sodium alginate (0.01% by mass / cement) was added was 105 when the 28-day compressive strength of Comparative Example 7 was 100. (Ie, +5), and the 28-day compressive strength in Comparative Example 10 to which only EDIPA (0.01% by mass / cement) is added is 105 (that is, when the 28-day compressive strength of Comparative Example 7 is 100). , +5), and these simple sums are +10 when the 28-day compressive strength of Comparative Example 7 is 100. Therefore, as shown in Table 2, in Example 15 in which sodium alginate (0.01% by mass / cement) and EDIPA (0.01% by mass / cement) are used in combination, sodium alginate (0.01% by mass / cement) is used. A synergistic effect of +2 compared to the simple sum of the long-term strength improving effect in Example 11 in which only cement) is added and the long-term strength improving effect in Comparative Example 10 in which only EDIPA (0.01% by mass / cement) is added. The effect was exhibited, and a remarkable effect of improving strength was observed.

Example 16 is an embodiment in which sodium alginate (0.01% by mass / cement) and TIPA (0.01% by mass / cement) are used in combination, and as shown in Table 2, 28th day of Comparative Example 7. The 28-day compressive strength of Example 16 when the compressive strength is 100 is 113 (that is, +13). On the other hand, as shown in Table 2, the 28-day compressive strength in Example 11 to which only sodium alginate (0.01% by mass / cement) was added was 105 when the 28-day compressive strength of Comparative Example 7 was 100. (Ie, +5), and the 28-day compressive strength in Comparative Example 11 to which only TIPA (0.01% by mass / cement) is added is 105 (that is, when the 28-day compressive strength of Comparative Example 7 is 100). , +5), and these simple sums are +10 when the 28-day compressive strength of Comparative Example 7 is 100. Therefore, as shown in Table 2, in Example 16 in which sodium alginate (0.01% by mass / cement) and EDIPA (0.01% by mass / cement) are used in combination, sodium alginate (0.01% by mass / cement) is used. A synergistic effect of +3 compared to the simple sum of the long-term strength improving effect in Example 11 in which only cement) is added and the long-term strength improving effect in Comparative Example 11 in which only EDIPA (0.01% by mass / cement) is added. The effect was exhibited, and a remarkable effect of improving strength was observed.

Example 17 is an embodiment in which sodium alginate (0.01% by mass / cement) and sorbitol (0.05% by mass / cement) are used in combination, and as shown in Table 2, 28th day of Comparative Example 7. The 28-day compressive strength of Example 17 when the compressive strength is 100 is 112 (that is, +12). On the other hand, as shown in Table 2, the 28-day compressive strength in Example 11 to which only sodium alginate (0.01% by mass / cement) was added was 105 when the 28-day compressive strength of Comparative Example 7 was 100. (Ie, +5), and the 28-day compressive strength in Comparative Example 12 to which only sorbitol (0.05 mass% / cement) is added is 104 (that is, when the 28-day compressive strength of Comparative Example 7 is 100). , +4), and these simple sums are +9 when the 28-day compressive strength of Comparative Example 7 is 100. Therefore, as shown in Table 2, in Example 17 in which sodium alginate (0.01% by mass / cement) and sorbitol (0.05% by mass / cement) are used in combination, sodium alginate (0.01% by mass / cement) is used. A synergistic effect of +3 compared to the simple sum of the long-term strength improving effect in Example 11 in which only cement) is added and the long-term strength improving effect in Comparative Example 12 in which only sorbitol (0.05% by mass / cement) is added. The effect was exhibited, and a remarkable effect of improving strength was observed.

Example 18 is an embodiment in which sodium alginate (0.01% by mass / cement) and sodium gluconate (0.05% by mass / cement) are used in combination, and as shown in Table 2, of Comparative Example 7. When the 28-day compressive strength is 100, the 28-day compressive strength of Example 18 is 112 (that is, +12). On the other hand, as shown in Table 2, the 28-day compressive strength in Example 11 to which only sodium alginate (0.01% by mass / cement) was added was 105 when the 28-day compressive strength of Comparative Example 7 was 100. (That is, +5), and the 28-day compressive strength in Comparative Example 13 to which only sodium gluconate (0.05 mass% / cement) is added is 103 when the 28-day compressive strength of Comparative Example 7 is 100. (That is, +3), and these simple sums are +8 when the 28-day compressive strength of Comparative Example 7 is 100. Therefore, as shown in Table 2, in Example 18 in which sodium alginate (0.01% by mass / cement) and sodium gluconate (0.05% by mass / cement) are used in combination, sodium alginate (0.01% by mass / cement) is used. Compared to the simple sum of the long-term strength improving effect in Example 11 in which only% / cement) is added and the long-term strength improving effect in Comparative Example 13 in which only sodium gluconate (0.05% by mass / cement) is added. A synergistic effect of +4 was exhibited, and a remarkable effect of improving strength was observed.

The cement strength improver and cement additive of the present invention are suitably used for cement compositions.

Claims (4)

With cement,
Containing additives for cement,
The cement additive is
A cement strength improver containing a polysaccharide having a gel-forming ability to gel in alkaline water,
It has at least one selected from the group consisting of the following A component, B component, and C component.
The content ratio of the following component A is 0.001% by mass to 0.5% by mass with respect to the cement.
The cement composition in which the content ratio of the following B component is 0.001% by mass to 0.5% by mass with respect to the cement.
Component A: A compound having a structure in which 5 mol or more of alkylene oxide is added to 1 mol of alcohol.
Component B: Alkanolamine compound.
Component C: At least one selected from the group consisting of keto acid or a salt thereof, and sugar alcohol. The cement composition according to claim 1, wherein the polysaccharide is at least one selected from the group consisting of alginic acid or a salt thereof, alginic acid ester, and glucomannan. The cement additive has the A component and has.
The component A is a polymer having a structural unit derived from polyethylene glycol or an alkylene oxide adduct of methacrylic acid, an alkylene oxide adduct of sorbitol, or a structural unit derived from an alkylene oxide adduct of 3-methyl-3-butenyl alcohol. The cement composition according to claim 1 or 2, which is at least one selected from the group consisting of a copolymer having, and an alkylene oxide adduct to active hydrogen bonded to an amino group of polyethyleneimine. The cement additive has the B component and has.
Claims 1 to 3 wherein the component B is at least one selected from the group consisting of triisopropanolamine, N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine, and diisopropanolethanolamine. The cement composition according to any of the above.