ES2362018T3 - DISPERSING AGENT FOR HYDRAULIC COMPOSITION. - Google Patents

Abstract

A dispersant for a hydraulic composition, comprising a polymer obtained by copolymerization of monomer 1 represented by the following formula (1), monomer 2 represented by the following formula (2), monomer 3 represented by the following formula (3) and monomer 4 represented by the following formula (4), at pH 7 or less, in which the proportion (Pm / Mn) of the average molecular weight by weight (Pm) with respect to the number average molecular weight (Mn) of the Polymer is 1.0 to 2.6: where each of R 1 and R 2 represents a hydrogen atom or a methyl group, R 3 represents a hydrogen atom or - (CH2) q (CO) pO ( AO) rR 4 in which AO represents an oxyalkylene group having 2 to 4 carbon atoms or an oxstyrene group, p represents a number of 0 or 1, q represents a number of 0 to 2, p and q are not simultaneously 0, r represents the molar number of the AO units added above the average per molecule and represents a number of 3 at 300, and R 4 represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms; wherein R 11 represents a hydrogen atom or a methyl group, R 12 represents an alkylene group having 2 to 12 carbon atoms, m1 represents a number from 1 to 30, and each of M 3 and M 4 represents a hydrogen atom, an alkali metal or an alkaline earth metal; in which each of R 13 and R 15 represents a hydrogen atom or a methyl group, each of R 14 and R 16 represents an alkylene group having 2 to 12 carbon atoms, each of m2 and m3 represents a number from 1 to 30, and M 5 represents a hydrogen atom, an alkali metal or an alkaline earth metal; and wherein each of R 17 to R 19 represents a hydrogen atom or a methyl group, (CH2) 5COOM 7 being optionally combined with COOM 6 or another (CH2) 5COOM 7 to form an anhydride without M 6 and M 7 in the groups, s represents a number from 0 to 2, and each of M 6 and M 7 represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an alkylammonium group, a substituted alkylammonium group, a alkyl group, a hydroxyalkyl group or an alkenyl group.

Description

Field of the Invention

The present invention relates to a dispersant for a hydraulic composition and a hydraulic composition.

Background of the invention

Among the additives of hydraulic composition there are the so-called high-performance water reducing agents that have a high effect to impart fluidity. Typical examples thereof include a condensate salt of naphthalenesulfonic acid / formaldehyde (based on naphthalene), a condensate salt of melamine sulfonic acid / formaldehyde (based on melamine), and a polycarboxylic acid having a polyoxyalkylene chain . However, when preparing concrete with a very small amount of water using a cement dispersant, the loss of settlement is significant and there is a problem of deterioration in the functionality with respect to the landfill property and applicability.

Accordingly, it has been proposed that a water-soluble vinyl copolymer that has loss of settlement be used while avoiding functionality itself in the form of a cement dispersant.

Concrete prepared using, as hydraulic powder, high-belite cement (cement with a high C2S content as a cement component), such as moderately thermal Portland cement or Low thermal Portland cement or slag cement prepared with Blast furnace slag cement may decrease settlement flow over time due to a reduced amount of a cement dispersant added to achieve the necessary fluidity.

High strength concrete has a problem, such as high viscosity concrete, since this concrete is prepared by kneading in a lower proportion of water / hydraulic powder (hereinafter referred to as water / cement ratio) than in the normal strength concrete (general strength).

This problem of viscosity increase has not yet been sufficiently resolved, even by the water reducing agent based on polycarboxylic acid, so an additive having a greater effect on reducing the viscosity of concrete is demanded.

In this background, JP-A 11-157897 describes an excellent additive with the ability to reduce the viscosity of high strength concrete and suppress the delay in setting of concrete, which contains as an essential component a vinyl copolymer that it contains a long chain oxyalkylene group, a short chain oxyalkylene group and a specific monomer.

JP-A 2000-327386 proposes that a polymer having both a monoester or a monoether having a polyalkylene glycol chain and a monomer having an unsaturated bond and a phosphate group are used to obtain a cement dispersant capable of showing excellent flow characteristics, a high dispersant effect and rapid setting, regardless of the proportion of water used to prepare the concrete.

WO-A 2006/006732 distributed on January 17, 2006 describes a polymer obtained from 3 types of monomers and the use thereof in a hydraulic composition.

Summary of the invention

The present invention relates to a dispersant for a hydraulic composition containing a polymer obtained by copolymerizing the monomer 1 represented by the following formula (1), the monomer 2 represented by the following formula (2), the monomer 3 represented by the following formula (3) and monomer 4 represented by the following formula (4), a pH 7 or less, in which the proportion (Pm / Mn) of the average molecular weight by weight (Pm) with respect to the average molecular weight in Number (Mn) of the polymer is 1.0 to 2.6:

image 1

wherein each of R1 and R2 represents a hydrogen atom or a methyl group, R3 represents a hydrogen atom or - (CH2) q (CO) pO (AO) rR4 in which AO represents an oxyalkylene group having 2 to 4 atoms of

5 carbon or an oxystyrene group, p represents a number of 0 or 1, q represents a number from 0 to 2, p and q are not simultaneously 0, r represents the molar number of AO units added above the average per molecule and represents a number from 3 to 300, and R4 represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms;

image2

wherein R11 represents a hydrogen atom or a methyl group, R12 represents an alkylene group having 2 to 12 carbon atoms, m1 represents a number from 1 to 30, and each of M3 and M4 represents a hydrogen atom , an alkali metal or an alkaline earth metal;

fifteen

image 1

in which each of R13 and R15 represents a hydrogen atom or a methyl group, each of R14 and R16 represents an alkylene group having 2 to 12 carbon atoms, each of m2 and m3 represents a number 20 of 1 to 30, and M5 represents a hydrogen atom, an alkali metal or an alkaline earth metal; Y

image 1

wherein each of R17 to R19 represents a hydrogen atom or a methyl group, (CH2) 5COOM7 being optionally combined with COOM6 or another (CH2) 5COOM7 to form an anhydride without M6 and M7 in the groups, s represents a number from 0 to 2, and each of M6 and M7 represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroxyalkyl group or an alkenyl group .

The present invention also provides a process for producing a phosphate based polymer, which includes the copolymerization of the monomer 1 represented by the above formula (1), the monomer 2 represented by the above formula (2), the monomer 3 represented by the formula (3) above, and the monomer 4 represented by the formula (4) above, at pH 7 or less in the presence of a chain transfer agent.

In addition, the present invention provides the use of the polymer described above or a polymer obtained in the process described above as a dispersant for a hydraulic composition.

Detailed description of the invention

In the hydraulic compositions, such as concrete in a region of ultra-high strength, the polymers of JP-A 11-157897 and JP-A 2000-327386 are desired to further improve fluidity and viscosity reduction. From the viewpoint of expanding the general versatility of materials, such as cement and aggregate, it is desired that polymers having structures other than those shown in JP-A 11-157897 can be used.

Many types of cements are currently used in hydraulic compositions represented by concrete, and not only cements of different mineral composition are used, but also cements with high belite content, such as moderately thermal Portland cement and low thermal Portland cement , or special cements, such as composite slag cement with blast furnace slag. Concrete with a proportion of water / hydraulic dust that varies over a wide range, particularly high strength concrete with a proportion of water / hydraulic dust that varies from 20 to 35% by weight, and general concrete that has a proportion of water / hydraulic dust greater than that of high strength concrete, are different from each other in the characteristics demanded. For manufacturers of hydraulic compositions, it is problematic that the dispersants used in the hydraulic compositions to be manufactured change depending on the compositions and materials thereof, and several tanks must be installed for various types of dispersants (2 to 10 m3 tank for each type) on the same floor. With this background, it is desirable that a dispersant used in hydraulic compositions show its universally necessary effect on hydraulic compositions having said variable formulation and materials.

In order to satisfy said demand, it is conceivable that in consideration of the characteristics of the components to be added, a plurality of components are combined to constitute a dispersant or additive for a hydraulic composition. In this case, it is conceivable that an excellent component is combined in the initial dispersant functionality (initial dispersant component), an excellent component in the dispersibility retention (dispersion retention component) is combined, and a component that entails some delay in the proper setting (retarding component) to achieve the effect of conferring dispersibility, fluidity and retention of fluidity with a good balance. However, the additives in JP-A 11-157897 and JP-A 2000327386 hardly show a sufficient effect for use from such a point of view.

The present invention provides a dispersant for a hydraulic composition that shows an excellent effect on dispersibility, fluidity and fluid retention for hydraulic compositions having various formulations and materials.

The present invention also provides a hydraulic composition containing the dispersant for a hydraulic composition of the present invention, hydraulic powder and water, in which the hydraulic powder is at least one member selected from the group having normal Portland cement, moderate Portland cement thermal, low thermal Portland cement and blast furnace slag cement.

Furthermore, the present invention provides a hydraulic composition containing the dispersant for a hydraulic composition of the present invention, hydraulic powder, fine aggregate, coarse aggregate and water, in which the water / hydraulic powder ratio is 20 to 60% by weight. , and the unit amount of water is 120 to 185 kg / m3.

According to the present invention, a dispersant is provided for a hydraulic composition that shows an excellent effect on dispersibility, fluidity and fluid retention for hydraulic compositions having various formulations and materials.

The polymer of the present invention is a polymer obtained by copolymerizing, at a pH of 7 or less, of the monomer 1 represented by the formula (1) above, the monomer 2 represented by the formula (2) above, the monomer 3 represented by the formula (3) above and the monomer 4 represented by the formula (4) above as the essential components. It is estimated that the carboxyl group in the formula (4) and the phosphate groups in the formulas

(2) and (3) to be introduced into the polymeric function as adsorption groups on hydraulic powder, and the oxyalkylene groups in the formula (1) function as groups for repulsion between hydraulic powder particles.

The characteristics of the carboxyl group and the phosphate group for adsorption on hydraulic powder are not evident, but they are estimated as follows:

Generally, a cement dispersant is composed of an "initial dispersion component" that shows dispersibility just after kneading and a "dispersion retention component" that shows dispersibility after a period of time. In the conventional polycarboxylic acid based dispersant, the proportion of the compound of the initial dispersion component with respect to the dispersion retention component varies depending on the desired composition (water / cement ratio) and the material (type of cement). That is, normal Portland cement and high-strength concrete that require a relatively large amount of the added dispersant satisfy retention by increasing the initial dispersion component, while slag cement, the high-belite cement (with a high C2S content) and the general strength concrete to which the dispersant is added in a relatively small amount, satisfies the retention of the dispersion by increasing the dispersion retention component. Therefore, the amount of each component in the cement dispersant varies depending on the desired composition and the material so that the different dispersants must be used to adapt to them.

In consideration of the amount of additive that is a variable factor depending on the type of cement, the chemical components contained in the cement are compounds, such as tricalcium silicate (C3S), dicalcium silicate (C2S), tricalcium aluminate (C3A) and aluminate ferrite tetracalcic (C4AF), depending on the burner. The initial dispersion component in a dispersant based on polycarboxylic acid tends to adsorb specifically on C3A contained in a relatively large amount in normal Portland cement. It follows that when a dispersant based on polycarboxylic acid in which the composition ratio of the initial dispersion component with respect to the dispersion retention component is optimized for cement with a relatively small amount of C3A, such as slag cement and cement with a high content of belite, which is used in normal Portland cement, the initial dispersion component in the polycarboxylic acid-based dispersant is specifically adsorbed in C3A undergoing a vigorous initial hydration reaction, and therefore, a considerable amount of the Initial dispersion component disappears in a few minutes in the initial phase of hydration (because the dispersant burns in hydrates), and therefore the dispersant does not reach the initial fluidity and tends to show fluidity over time through the component of dispersion retention (when the amount of the initial dispersion component added is increased to show initial fluidity, the dispersion retention component becomes excessive to show additional fluidity over time). On the other hand, when the dispersant in which the preparation ratio of the compound of the initial dispersion component with respect to the dispersion retention component is optimized for the normal Portland cement used in the slag cement or the cement with high content in belita, the amount of the dispersant added thereto is insufficient, therefore resulting in not achieving a fluid retention effect.

The phosphate group, in comparison with the carboxyl group, is not specifically adsorbed on cement minerals, but, due to a lower water solubility, they can be influenced by the concentration of a salt that accompanies a cement hydration reaction. That is, normal Portland cement that contains a large amount of C3A undergoes a vigorous initial hydration reaction, the adsorption rate of the phosphate group tends to increase in the cement with a higher concentration of a salt in water, while the speed of Adsorption thereof tends to decrease in slag cement and cement with a high content of belite with a smaller amount of C3A.

Accordingly, it is estimated that containing an optimized proportion of the carboxyl group and the phosphate group having different adsorption characteristics, the dispersant may also show its necessary effect on hydraulic compositions having various formulations and materials.

(Monomer 1)

In monomer 1, each of R1 and R2 in formula (1) represents a hydrogen atom or a methyl group. R3 represents a hydrogen atom or - (CH2) q (CO) pO (AO) rR4 and is preferably a hydrogen atom. Examples of the alkenyl in the formula (1) include an allyl group, a metal group, etc. AO is linked with (CH2) q through an ether bond when p is 0 and with an ester bond when p is 1. q represents a number from 0 to 2, preferably 0 or 1 and more preferably 0. p and q are not simultaneously 0. AO is an oxyalkylene group having 2 to 4 carbon atoms or an oxstyrene group. AO is preferably an oxyalkylene group having 2 to 4 carbon atoms and more preferably containing an ethyleneoxy group (hereinafter referred to as the EO group) in which the amount of the EO group is preferably 70% by mol or more, more preferably 80% in mol or more, and even more preferably 90% in mol or more. It is even more preferred that AO be all EO groups. r is the number of AO units added on the average per molecule and represents a number from 3 to 300, and with respect to the dispersive effect of the dispersibility and viscosity of the polymer in the hydraulic composition, r is from 3 to 300, preferably of 4 to 120, even more preferably from 4 to 80, even more preferably from 4 to 50 and even more preferably from 4 to 30. AO may be different from each other in the unit repeated by r on the average, which contains a random addition, a block addition or a combination of random addition and block addition. For example, AO may contain a propyleneoxy group or the like, in addition to the EO group.

R4 represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms, preferably an alkyl group having 1 to 12, preferably 1 to 4 and more preferably 1 or 2 carbon atoms and is even more preferably a methyl group.

Preferred examples of monomer 1 include an esterified compound or a semi-esterified compound of a polyalkylene glycol protected by an alkyl terminal, such as methoxypolyethylene glycol, methoxypolypropylene glycol, methoxy polybutylene glycol, methoxy polystyrene glycol or ethoxypolyethylene polypropylene glycols or acidic acidic compounds of these glycols with (meth) allyl alcohols, and adducts obtained by adding alkylene oxides having 2 to 4 carbon atoms to (meth) acrylic acid, maleic acid or (meth) allyl alcohol. The term "(meth) acrylic acid" refers to acrylic acid and / or methacrylic acid, and the term "(meth) allyl" refers to allyl and / or metalyl (this is used hereafter).

More preferred are alkoxy compounds, especially esterified compounds of methoxypolyethylene glycol and (meth) acrylic acid. Specific examples of these esterified compounds may include methoxypolyoxyalkylene methacrylate and -methoxypolyoxyalkylene acrylate. Among these compounds, -methoxypolyoxyalkylene methacrylate is more preferred.

The monomer 1 used in the production of the polymer of the present invention can be obtained, for example, by an esterification reaction of an alkoxypolyalkylene glycol with a (meth) acrylic acid. The unreacted (meth) acrylic acid in the esterified product can be used as monomer 4. The amount of unreacted (meth) acrylic acid in the esterified product is preferably 5% by weight or less, more preferably 3% by weight. or less, even more preferably 1.5% by weight or less and even more preferably 1% by weight or less based on the monomer 1 converted into a type of acid, from the viewpoint of the reduction in quantity variation of monomer 4 and the preparation of its constant necessary amount when used as a concrete dispersant. Examples of a process that reduces the amount of (meth) acrylic acid that remains uncapped in the production of monomer 1 include finishing, water vapor and solvent extraction.

(Monomer 2)

In monomer 2, R11 in formula (2) is a hydrogen atom or a methyl group, and R12 is an alkylene group

5 which has 2 to 12 carbon atoms. m1 is a number from 1 to 30, and M3 and M4 are respectively a hydrogen atom, an alkali metal or an alkaline earth metal. m1 in the formula (2) is preferably from 1 to 20, more preferably from 1 to 10 and even more preferably from 1 to 5.

Specific examples of monomer 2 including monoester phosphate of organic hydroxy compounds. Specific examples include polyalkylene glycol mono (meth) acrylate acid phosphate. Examples include mono (2-hydroxyethyl) methacrylic acid phosphate and mono (2-hydroxyethyl) acrylic acid phosphate. Among these compounds, mono (2-hydroxyethyl) methacrylic acid phosphate is preferred from the viewpoint of ease of production and product quality stability. Monomer 2 may be an alkali metal salt, an alkaline earth metal salt, an ammonium salt or an alkylammonium salt of such a compound.

fifteen

(Monomer 3)

In formula (3) of monomer 3, each of R13 and R15 represents a hydrogen atom or a methyl group, and each of R14 and R16 represents an alkylene group having 2 to 12 carbon atoms. Each of m2 and m3 represents a number from 1 to 30, and M5 is a hydrogen atom, an alkali metal or an alkaline earth metal. Each of m2 and m3 in the formula (3) is preferably from 1 to 20, more preferably from 1 to 10 and even more preferably from 1 to 5.

Specific examples of monomer 3 include diester phosphates of organic hydroxy compounds. The

Specific examples include polyalkylene glycol di (meth) acrylate diester phosphate. Examples include di- [(2-hydroxyethyl) methacrylic acid phosphate] and di- [(2-hydroxyethyl) acrylic acid phosphate]. Among these compounds, di- [(2-hydroxyethyl) acrylic acid phosphate] is preferred from the viewpoint of ease of production and stability of product quality. The monomer 3 may be an alkali metal salt, an alkaline earth metal salt, an ammonium salt or an alkylammonium salt of said compound.

Monomers 2 and 3 can be used as a monomeric mixture containing monomers 2 and 3. Like monomer 2 and monomer 3, a phosphate obtained by reacting an organic hydroxy compound represented by formula (5) can be used with an agent of phosphorylation

The monomer mixture of monomers 2 and 3 can be produced as a reaction product by reacting an organic hydroxy compound represented by the formula (5) with a phosphorylation agent at a predetermined loading ratio.

image 1

wherein R20 represents a hydrogen atom or a methyl group, R23 represents an alkylene group having 2 to 12 carbon atoms and m4 represents a number from 1 to 30.

m4 in the formula (5) is preferably from 1 to 20, more preferably from 1 to 10 and even more preferably from 1 to 5.

The phosphorylation agent includes orthophosphoric acid, phosphorus pentoxide (phosphoric anhydride), polyphosphoric acid, phosphorus oxychloride and the like, among which orthophosphoric acid and phosphorus pentoxide are preferred. These can be used alone or as a mixture of two or more thereof. The amount of the phosphorylation agent when reacting with the organic hydroxy compound can be suitably determined depending on the desired phosphate composition.

When a mixture of mono (2-hydroxyethyl) methacrylic acid phosphate and di- [(2-hydroxyethyl) methacrylic acid] phosphate It is produced in the form of phosphate, it can be synthesized by known technological procedures (for example, JP-A 57-180618). As the monomer mixture containing monomers 2 and 3, a product available in the market that contains a monoester and a diester. These products are available under the name of Phosmer M, Phosmer PE and Phosmer P (Unichemical), JAMP514, JAMP514P and JMP100 (all these products are manufactured by Johoku Chemical Co., Ltd.), Light Ester P-1M, Light Acrylate P-1A (all these products are manufactured by Kyoelsha Formula Kogyo), MR200 (Dalhachi Chemical Industry Co., Ltd.), Kayamer (Nippon Kayaku Co., Ltd.) and phosphate from ethylene glycol methacrylate (Aldrich reagent).

Monomers 2 and 3 are phosphate monomers having an unsaturated bond and a hydroxyl group and it has been confirmed that commercially available products and the above reaction products contain products other than a monoester (monomer 2) and a diester (monomer 3). Although it is considered that polymerizable compounds and non-polymerizable compounds are to be mixed in these other compounds, such a mixture (monomeric mixture) can be used as such in the present invention.

(Monomer 4)

In monomer 4, each of R17 to R19 in formula (4) represents a hydrogen atom, a methyl group or (CH2) sCOOM7 that can be combined with COOM6 or another (CH2) sCOOM7 to form an anhydride. In this case, M6 and M7 in these groups are not present. s represents a number from 0 to 2. R17 is preferably a hydrogen atom and R18 is preferably a methyl group. R19 is preferably a hydrogen atom or (CH2) sCOOM7.

each of M6 and M7 represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroxyalkyl group or an alkenyl group. Each of M6 and M7 is preferably a hydrogen atom or an alkali metal.

Specific examples of monomer 4 include monomers based on monocarboxylic acid, such as (meth) acrylic acid and crotonic acid, monomers based on dicarboxylic acid, such as maleic acid, itaconic acid and fumaric acid, or anhydrides or salts (eg, salts of alkali metals, alkaline earth metal salts or ammonium salts, mono, di or trialkyl ammonium salts (from 2 to 8 carbon atoms) whose hydroxyl group may be substituted) or esters. Preferred examples of monomer 4 include (meth) acrylic acids, maleic acid and maleic acid anhydrides. The most preferred examples of monomer 4 include (meth) acrylic acids or alkali metal salts of these acids. The (meth) acrylic acid refers to acrylic acid and / or methacrylic acid (this is used hereinafter).

The polymer according to the present invention is a complex polymer of phosphate group / carboxyl group obtained by copolymerizing monomers 1, 2, 3 and 4 at pH 7 or less. It is preferred to use a monomer mixture containing monomers 2 and 3.

Preferred compounds such as monomers 1, 2, 3 and 4 are those described above. In addition, the commercially available products and reaction products mentioned above can be used.

In the copolymerization of monomers, the proportion of monomer 1 in the total monomers used in the polymerization is preferably 60 to 98% by weight, more preferably 70 to 95% by weight, even more preferably 70 to 90% by weight. The total sum of monomers 2 and 3 is preferably 1 to 39% by weight, more preferably 2 to 28% by weight, even more preferably 5 to 25% by weight. The proportion of monomer 4 is preferably from 1 to 39% by weight, more preferably from 1 to 28% by weight, even more preferably from 1 to 15% by weight.

The molar ratio of monomer 1 with respect to monomers 2, 3 and 4 (ie, monomer 1 / (monomer 2 + monomer 3 + monomer 4)) is preferably 5/95 to 95/5, more preferably 10 / 90 to 90/10. The molar ratio of monomers 2 and 3 with respect to monomer 4 (ie, (monomer 2 + monomer 3) / monomer 4) is preferably 5/95 to 95/5, more preferably 10/90 to 90/10 . With respect to monomers 2, 3 and 4 in the invention, each proportion by weight,% by weight, molar ratio and% by mole is calculated based on the acid-based compounds, which are used hereafter.

In the production of the polymer, the proportion of monomer 3 in all monomers used in the reaction is preferably 1 to 15% by weight, more preferably 1 to 12% by weight, even more preferably 2 to 10% by weight and even more preferably 3 to 6% by weight. Monomer 3 gives a branched structure to the resulting polymer. The polymer of the present invention has a suitable branched structure so that after adsorption on hydraulic powder, the polymer can reduce its space in the hydraulic powder. Therefore, a large number of polymers can be adsorbed on the hydraulic powder, and when the Pm / Mn value is in a specific range and the molecular weight distribution is narrow, a large additional number of polymers can be adsorbed on the hydraulic powder. As a result, they will be considered to show excellent dispersibility, fluidity and fluid retention.

In addition, the molar ratio of monomer 2 with respect to monomer 3 (monomer 2 / monomer 3) is preferably 99/1 to 4/96 and more preferably 99/1 to 5/95.

From the point of view of suppression gelation, the monomer solution containing monomer 3 is preferably used at pH 7 or less in the reaction.

The most preferred production conditions will be explained from the point of view of gelation and the limiting control of the preferred molecular weight and also from the point of view of the design of functionality of the dispersant for a hydraulic composition. From these points of view, a chain transfer agent is used in an amount of preferably 4% in mol or more, more preferably 6% in mol or more and even more preferably 8% in mol or more, based to the total number of moles of monomers 1, 2, 3 and 4 in the copolymerization. In addition, the upper limit of the amount of the chain transfer agent to be used is preferably 100% mol or less, more preferably 60% mol or less, even more preferably 30% mol or less and even more preferably 15% by mole or less based on the number of total moles of monomers 1, 2, 3 and 4. The amount of the chain transfer agent is preferably from 4 to 60% by mole, more preferably from 6 30% in mol and even more preferably 8 to 15% in mol.

The reaction of monomers 2, 3 and 4 is carried out at a target index of, preferably, 60% or more, more preferably 70% or more, even more preferably 80% or more, even more preferably 90% or more and even more preferably 95% or more. The amount of the chain transfer agent to be used can be selected from the previous point of view. In this document, the reaction rate of monomers 2, 3 and 4 is calculated by the following equation.

Reaction Speed (%) = (1 - Q / P) x 100

Q: Proportion of unsaturated ethylenic bonds of monomers 2, 3 and 4 with respect to R4 obtained from monomer 1 in the reaction system after the reaction has ended

P: Proportion of unsaturated ethylenic bonds of monomers 2, 3 and 4 with respect to R4 obtained from monomer 1 in the reaction system at the start of the reaction.

The proportions (mol%) of unsaturated ethylenic bonds of monomers 2, 3 and 4 in a phosphorus-containing compound in the reaction system at the beginning and at the end of the reaction can be calculated based on the result of the following 1H measurement NMR

(1H-NMR condition)

A material obtained under reduced pressure by drying the polymer dissolved in water is dissolved in a concentration of 3 to 4% by weight in heavy methanol for the measurement of 1 H-NMR. The residual rate of unsaturated ethylenic bonds is measured by calculating an integral value in the range of 5.5 to 6.2 ppm. The 1H-NMR measurement is performed using "Mercury 400 NMR" manufactured by Varian Company under the following conditions: the number of data points: 42052, measurement range: 6410.3 Hz, pulse width: 4.5 s , pulse waiting time: 10 x and measurement temperature: 25.0ºC.

In polymer production, other polymerizable monomers may be used in addition to the monomers 1, 2, 3 and 4 mentioned above. Examples of the other polymerizable monomers may include allylsulfonic acid, metalylsulfonic acid or alkali metal salts, alkaline earth metal salts, ammonium salts or amine salts of any of these acids. In addition, examples of the other polymerizable monomers may include acrylic acid monomers, such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid and citraconic acid. The other polymerizable monomers may be alkali metal salts, alkaline earth metal salts, ammonium salts, amine salts, methyl esters, ethyl ester or anhydrides, such as maleic anhydride, of at least one acid. Examples of the other polymerizable monomers also include (meth) acrylamide, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, 2- (meth) acrylamide-2-metasulfonic acid, 2- (meth) acid acrylamide-2-ethanesulfonic acid, 2- (meth) acrylamide-2-propane sulfonic acid, styrene and styrenesulfonic acid. The total proportion of monomers 1, 2 and 3 is preferably from 30 to 100% by mole, more preferably from 50 to 100% by mole, even more preferably from 75 to 100% by mole, even more preferably from 95 to 100% in mol, even more preferably from 97 to 100% in mol and even more preferably 100% in mol in all monomers.

In polymer production, the above monomers are preferably copolymerized in the presence of a predetermined amount of a chain transfer agent. In addition, other copolymerizable monomers, a polymerization initiator and the like can be used.

The reaction temperature between monomers 1, 2, 3 and 4 is preferably from 40 to 100 ° C and more preferably from 60 to 90 ° C and the reaction pressure is a reaction as a manometric pressure is preferably from 101.3 to 111, 5 kPa (from 1 to 1.1 atm) and more preferably from 101.3 to 106.4 kPa (from 1 to 1.05 atm).

The pH of the reaction system can be adjusted using inorganic acids (for example, phosphoric acid, hydrochloric acid, nitric acid and sulfuric acid) and NaOH, KOH, triethanolamine and the like as necessary.

In this document, a monomer solution containing monomer 3 is preferably a system containing water (specifically, the solvent contains water) in view of the pH measurement. In the case of a non-aqueous system, a necessary amount of water can be added to perform the measurement. The pH of the monomer solution is preferably 7 or less, more preferably 0.1 to 6, even more preferably 0.2 to 4.5 and even more preferably 0.5 to 3 from the point of view of uniformity. of the monomer solution, prevention of gelation and restriction in the reduction of functionalities. In addition, monomer 1 is preferably used in the form of a monomer solution having a pH of 7 or less. This pH is one measured at 20 ° C.

In the present invention, the pH of a reaction solution at 20 ° C sampled during the course of the reaction (from the beginning of the reaction to the end of the reaction) is the pH during the reaction. It is preferable to start the reaction in such a condition so that the pH of the solution during the reaction is clearly 7 or less (proportion of the monomers, solvent and other components).

When the reaction system is non-aqueous type, water in a measurable amount of pH can be added to the reaction system to measure its pH.

If the reaction of monomers 1, 2, 3 and 4 is carried out under the conditions shown in the following points (1) and (2) in the polymer production process, the reaction pH is normally considered to be 7 or minor in consideration of other conditions.

(one)

 A monomer solution containing all monomers 1, 2, 3 and 4 and having a pH of 7 or less is used for the copolymerization reaction of monomers 1, 2, 3 and 4.

(2)

 The copolymerization reaction of monomers 1, 2, 3 and 4 begins at a pH of 7 or less. Specifically, after the reaction system containing monomers 1, 2, 3 and 4 is lowered to a pH of 7 or less, the reaction begins.

(Chain transfer agent)

The chain transfer agent is a material that has the function of initiating a chain transfer reaction (a reaction in which the growing polymer radicals are reacted with other molecules to cause the active points of radicals that will be transferred) and added with the intention of transferring a chain unit.

Examples of the chain transfer agent include thiol-based chain transfer agents and hydrocarbon halide-based chain transfer agents. Among these agents, thiol-based chain transfer agents are preferred.

As the thiol-based chain transfer agent, preferably those having a -SH group and, especially, those represented by the formula HS-R-Eg (in which R represents a group obtained from a hydrocarbon having 1 to 4 carbon atoms, E represents a group -OH, -COOM, -COOR 'or -SO3M, in which M represents a hydrogen atom, a monovalent metal, a divalent metal, an ammonium group or an amine group organic, R 'represents an alkyl group having 1 to 10 carbon atoms and g represents an integer from 1 to 2). Examples of the thiol-based chain transfer agent include mercaptoethanol, thioglycerol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, octyl thioglycolate and octyl 3-mercaptopropionate. Mercaptopropionic acid and mercaptoethanol are preferred and mercaptopropionic acid is more preferred from the viewpoint of a chain transfer effect in the copolymerization reaction of the system containing monomers 1 to 3. One or two or more of these compounds may be used.

Examples of hydrocarbon halide based chain transfer agent include carbon tetrachloride and carbon tetrabromide.

Examples of other chain transfer agents may include -methylstyrene, terpinolene, terpinen, -terpinen, dipentene and 2-aminopropane-1-ol dimer. These chain transfer agents can be used alone or in combinations of two or more.

(Polymerization Initiator)

In the polymer production process, it is preferred to use a polymerization initiator, and particularly the polymerization initiator is preferably used in an amount of preferably 5% by mol or more, more preferably from 7 to 50% by mol and even more preferably from 10 to 30% in mol based on the number of total moles of monomers 1, 2, 3 and 4.

As an aqueous type initiator, ammonium persulfate or an alkali metal salt, hydrogen peroxide or a water soluble azo compound, such as 2,2'-azobis (2-amidinopropane) dihydrochloride and 2,2'azobis may be used. (2-Methylapropanoamide) dihydrate. In addition, a promoter, such as sodium hydrogen sulphite or an amine compound may be used together with the polymerization initiator.

(Solvent)

In the polymer production a solution polymerization process can be carried out. Examples of the solvent used in this case include water or solvents such as those containing water containing water and methyl alcohol, ethyl alcohol, acetone isopropyl alcohol, methyl ethyl ketone or the like. Water is preferred in consideration of the handling characteristics and the reaction equipment. In the case where, in particular, an aqueous solvent is used, the pH of the monomer solution containing 3 is preferably 7 or less, more preferably 0.1 to 6 and even more preferably 0.2 to 4 to perform the copolymerization reaction at the point of uniformity (handling characteristics) of the solution of the monomer mixture, the reaction rate of the monomers and from the point of view of limiting cross-linking by hydrolysis of a pyro form of a compound based in phosphoric acid.

An example of the polymer production process will be explained. A reactor is charged with a predetermined amount of water, the atmosphere in the reactor is replaced with inert gas, such as nitrogen, and the reactor temperature rises. A mixture obtained by mixing and dissolving monomers 1, 2, 3 and 4 and the chain transfer agent in water and a mixture obtained by dissolving the polymerization initiator in water are prepared in advance and added dropwise in the reactor for 0 , 5 to 5 hours. At this time, each monomer, the chain transfer agent and the polymerization initiator can be added dropwise separately. In addition, a process can be adopted in which a reactor is charged with a monomeric mixture solution to which only the polymerization initiator is added dropwise. Specifically, the chain transfer agent, the polymerization initiator and other additives may be added as a solution of additives separately from the monomer solution or composing them in the monomer solution. However, they are preferably administered to the reaction system as the solution of additives separately from the monomer solution in view of the polymerization stability. In any case, the pH of the solution containing monomer 3 is preferably 7 or less. In addition, a copolymerization reaction is carried out maintaining a pH of preferably 7 or less using an acidic agent, etc. and the reaction solution is preferably matured for a predetermined time. In this case, the polymerization initiator can be added dropwise throughout its amount simultaneously with the monomers or in batches. However, it is preferred to add the batch polymerization initiator in order to reduce unreacted monomers. For example, it is preferred to add the polymerization initiator in an amount of 1/2 to 2/3 with respect to the total amount to be added simultaneously with the monomers and add the remaining initiator successively for maturation for 1 2 hours after the dropwise addition of the monomers ends. After maturation ends, the matured solution is neutralized by an alkaline agent (for example, sodium hydroxide) as necessary to obtain the polymer of the present invention. This production example is preferred according to the production process of polymer A according to the present invention.

The total amount of monomers 1, 2, 3 and 4 and the other copolymerizable monomers is preferably 5 to 80% by weight, more preferably 10 to 65% by weight and even more preferably 20 to 50% by weight.

The weight average molecular weight (Pm) of the polymer is preferably 10,000 to 100,000. Polymer A has a Pm of 10,000 or more, preferably 12,000 or more, more preferably 13,000 or more, even more preferably 14,000 or more and even more preferably 15,000 or more from the viewpoint of the dispersing effect and the effect. viscosity reducer, and 100,000 or less, preferably 95,000 or less, more preferably 90,000 or less, even more preferably 85,000 or less and even more preferably 80,000 or less from the point of view of suppressing an increase in Molecular weight due to crosslinking and limitation of gelation and from the point of view of improving yields, include a dispersing effect and a viscosity reducing effect. The polymer Pm is preferably of

12,000 to 950,000, more preferably from 13,000 to 90,000, even more preferably from 14,000 to 85,000 and even more preferably from 15,000 to 80,000. The Pm is even more preferably from 20,000 to 60,000 and even more preferably from 30,000 to 50,000 from both of the points of view mentioned above. The polymer preferably has a Pm in this range.

In the present invention, the Pm / Mn is 1.0 to 2.6, in which the Mn is the number average molecular weight. Pm / Mn is the degree of dispersion, and since Pm / Mn is closer to 1, the molecular weight distribution focuses on monodispersity, and as Pm / Mn is increased (made from 1), the distribution of molecular weight is extended.

The Pm / Mn of the polymer is preferably 1.0 to 2.4, more preferably 1.0 to 2.2, even more preferably 1.0 to 2.0 and even more preferably 1.0 to 1, 8, from the point of view of dispersibility and the viscosity reducing effect.

The polymer of the present invention having the value of Pm / Mn described above is mainly characterized as being a polymer, although it has a branched structure based on the structure of the monomer 3 ester, which has a molecular weight distribution very limited The polymer of the present invention can preferably be produced by regulating, for example, the amount of a chain transfer agent. As the amount of a chain transfer agent increases, the value of Pm / Mn decreases.

The Pm and Mn of the polymer are values measured by gel permeation chromatography (GPC) under the following conditions. It should be appreciated that the Pm / Mn of the polymer in the present invention is calculated based on polymer peaks.

(Condition of the GPC Analysis)

Columns: G4000PWXL + G2500PWXL (Tosoh)

Eluent: 0.2 M phosphoric acid buffer / CH3CN = 9/1

Flow rate: 1.0 ml / min

Column temperature: 40ºC

Detection: Rl

Sample size: 0.2 mg / ml Conventional material: Polyethylene glycol

In addition, in the pattern of a graph showing the distribution of molecular weights obtained by a GPC procedure under the above conditions, it is more preferred that the area of molecular weight distribution of 100,000 or more be 5% or less of the entire area in view of dispersibility (reduction in the amount required) and the viscosity reducing effect.

<Dispersant for a hydraulic composition>

From the viewpoint of showing the fluidity and the viscosity reducing effect, the dispersant for a hydraulic composition of the present invention is used in an amount of preferably 0.1 to 5 parts by weight in terms of a solid content, more preferably 0.2 to 3 parts by weight, based on 100 parts of hydraulic powder, particularly cement.

The dispersant for a hydraulic composition of the present invention may contain other additives (materials). Examples of these additives include AE agents, such as resin soap, saturated or unsaturated fatty acid, sodium hydroxystearate, lauryl sulfate, alkylbenzenesulfonic acid (salt), alkanesulfonate, polyoxyalkylene alkyl (phenyl) ether, polyoxyalkylene alkyl (phenyl) ether sulfate (salt), polyoxyalkylene alkyl (phenyl) ether phosphate (salt), protein material, alkenyl succinic acid and -olefin sulfonate; foaming agents; thickeners; silica sand; AE water reducing agents; initial resistance agents or promoters, such as soluble calcium salts, for example, calcium chloride, calcium nitrite, calcium nitrate, calcium bromide and calcium iodide, chlorides, for example, iron chloride and magnesium chloride, sulfates, potassium hydroxide, hydroxide sodium, carbonates, thiosulfates, formic acid (salt) and alkanolamine; foaming agents; waterproofing agents, such as resinous acid (salt), esters of fatty acids, fatty acids, silicone, paraffin, asphalt and wax; blast furnace slag; fluidizing agents; antifoaming agents, such as a type of dimethylpolysiloxane, a type of polyalkylene glycol fatty acid esters, a type of mineral oil, a type of fatty acid, a type of oxyalkylene, a type of alcohol and a type of amide; defoamers; fly ash; high-performance water reducing agents, such as a type of condensate of melamine sulfonic acid formalin, a type of aminosulfonic acid and a type of polymaleic acid; silica smoke; antioxidants, such as nitrites, phosphates and zinc oxide; water soluble polymers, such as those of the synthetic type, for example, polyacrylic acid amide, polyethylene glycol and EO adducts for oleyl alcohol or reaction products of EO adducts and vinylcyclohexene diepoxide; and emulsions of polymers, such as alkyl (meth) acrylates. The concentration of the polymer is 20 to 100% by weight, preferably 20 to 80% by weight, more preferably 25 to 70% by weight and even more preferably 30 to 70% by weight in the total solid of the concrete dispersant. of the present invention.

The polymer of the present invention can be used individually, but is preferably used together with the "dispersion retention component" (hereinafter referred to as a retention agent) from the viewpoint of improving the performance of retention In this case, the polymer of the invention / the retention agent is preferably from 20/80 to 90/10, more preferably from 25/75 to 80/20. The retention agent is not limited, but is preferably a polymer that does not contain monomer 4 and is obtained by copolymerization at pH 7 or less of monomers 1, 2 and 3.

The retention agent is an agent that adsorbs onto the hydraulic powder with time to exhibit the fluidity of a hydraulic composition. Using the polymer of the present invention together with the retention agent, the fluidity of the hydraulic composition can be maintained even if the time has elapsed after they have been kneaded.

When the polymer of the present invention is used together with the retention agent, the hydraulic composition has fluidity even if the time has elapsed after they have been kneaded, and therefore, the composition is useful in the event that time since the freshly prepared concrete (the concrete is not yet solidified) is produced in a factory until when the freshly prepared concrete is transported to a place where the concrete is going to be formwork is long, for example 30 minutes or more.

On the other hand, the polymer of the present invention is preferably used only in the case that freshly prepared concrete is produced on the same floor or that the time from when freshly prepared concrete is produced until when freshly prepared concrete is transported to the place of application be short, for example less than 30 minutes.

As described above, the retention agent is not limited since the polymer of the present invention is adsorbed onto hydraulic powder during the initial hydration reaction immediately after kneading the hydraulic powder with water, thus showing the effect of the The present invention, and therefore, it is estimated that the retention agent that adsorbs on hydration powder with time to show fluidity does not affect adsorption during the initial hydration reaction just after the polymer of the present invention is Knead with hydraulic dust and water.

In order for the polymer to adsorb on hydraulic powder with time to express the fluidity of the hydraulic composition, the phosphate-based polymer obtained by copolymerizing monomers 1, 2 and 3 at pH 7 or less is a polymer that uses the monomers in which the The proportion of monomer 1 in the total monomers used in the polymerization is preferably 60 to 90% in mol, more preferably 60 to 85% in mol and even more preferably 65 to 80% in mol, and the total sum of monomers 2 and 3 is preferably from 10 to 40% by mole, more preferably from 15 to 40% by mole and even more preferably from 20 to 35% by mole. The proportion of monomers 2 and 3 may be the same molar ratio as used in the polymer of the present invention.

The simultaneous use of a retention agent for the dispersant based on polycarboxylic acid is also effective. Examples of the retention agent for the polycarboxylic acid-based dispersant include a polymer obtained by copolymerizing monomer 1 with monomer 4. For the retention agent to be adsorbed on hydraulic powder in time to express the fluidity of the hydraulic composition, the polymer uses the monomers in which the proportion of monomer 1 in the monomers used in the polymerization is preferably from 20 to 70% by mole, more preferably from 25 to 60% by mole and even more preferably from 30 to 50% by mole, and the proportion of monomer 4 is preferably from 30 to 80% by mole, more preferably from 40 to 75% by mole and even more preferably from 50 to 70% by mole. Among these, a phosphate-based polymer retention people is preferable from the viewpoint of suppressing the thickness of the hydraulic composition over time.

<Hydraulic composition>

The hydraulic composition as the object of the present invention is a hydraulic composition containing hydraulic powder and water, and the hydraulic powder is a powder that has physical properties such that it matures by a hydration reaction. Examples of hydraulic dust include cement and plaster. Preferred examples of hydraulic powder include cements, such as normal Portland cement, belite cement, moderately thermal cement, rapid initial strength cement, super fast initial strength cement and sulfuric acid anti-cement. In addition, blast furnace slag, flying ash, silica smoke, stone dust (calcium carbonate powder) or the like can be added to these cements. The hydraulic compositions that are finally obtained by adding sand or sand and ballast as aggregates (fine aggregates, coarse aggregates) to these powders are called mortar or concrete. The dispersant and hydraulic composition of the present invention are useful in the fields of freshly mixed concrete products and concrete vibration and also in all other fields of various concretes, such as self-leveling concrete, retardant concrete products to fire, mortar concrete, gypsum suspension concrete, light weight concrete or heavy concrete, AE concrete, repair concrete, preloaded concrete, tremie concrete, white cement concrete, foundation improvement concrete, and concrete used in Frost times

The proportion of the proportion by weight of water / hydraulic dust (percentage of water / hydraulic dust in the suspension, usually abbreviated as A / P, or sometimes as A / C when the dust is cement) in the hydraulic composition (particularly concrete) as the subject of the present invention is 65% or less, preferably 10 to 60%, more preferably 12 to 57%, even more preferably 15 to 55% and even more preferably 20 to 55%. Particularly, when incorporated at a high intensity of 20 to 35%, the effect of the dispersant of the present invention is significantly shown in various cements.

From the point of view of the suppression of the amount of cement (economic efficiency), the amount of water per m3 of the hydraulic composition of the present invention, that is, the unit amount of water, is preferably 120 to 185 kg / m3. When the A / P ratio is 20 to 60% by weight, the unit amount of water is particularly preferably in this range.

Examples

Hereinafter, the present invention is described by reference to the Examples, but the scope of the present invention is not limited to the following examples.

Production Example (R-1) A glass reactor (four-mouth flask) equipped with a stirrer was charged with 367 g of water, the reactor atmosphere was replaced with nitrogen with stirring, and the water temperature rose to 80 ° C in an atmosphere of nitrogen. Two solutions were added dropwise to the water, that is, a monomer solution prepared by mixing 426 g (effective content, 60.8% by weight; water content, 35% by weight) of -methoxypolyethylene glycol monomethacrylate ( number of ethylene oxide units added on average per molecule, 23), 64.2 g of methacrylic acid and 3.2 g of 3-mercaptopropionic acid and then adjusting the mixture to pH 2.0 with 85% phosphoric acid , and a solution prepared by adding 11.4 g of ammonium persulfate in 64 g of water, respectively for 1.5 hours. After the mixture matured for 1 hour, a solution prepared by dissolving 5.7 g of ammonium persulfate persulfate in 32 g of water was added to the resulting mixture for 30 minutes, which was then ripened at the same temperature (80 ° C ) for 1.5 hours. After the mixture matured for 1 hour, a solution prepared by dissolving 5.7 g of ammonium persulfate in 32 g of water was added to the resulting mixture for 30 minutes. Then, the mixture was ripened at the same temperature (80 ° C) for 1.5 hours. After the maturation of the mixture ended, the mixture was neutralized to pH 6.0 by adding a 32% aqueous solution of sodium hydroxide dropwise to obtain an R-1 polymer having a weight average molecular weight of 48000 (coefficient reaction: 100%).

The types of the monomers, the% by mole and the% by weight thereof, the proportion of monomer 3 in the total monomers, the pH during the reaction, the average molecular weight and the proportion (Pm / Mn) of the molecular weight Average by weight with respect to the number average molecular weight of the resulting polymer are shown in Table 1.

Production Example (R-2)

A glass reactor (four-mouth flask) equipped with an agitator was charged with 352 g of water, the atmosphere in the reactor was replaced with nitrogen with stirring, and the temperature of the water was raised to 80 ° C under a nitrogen atmosphere. Two solutions were added dropwise to the water, that is, a mixture prepared by mixing 397 g (effective content, 60.8% by weight; water content, 35% by weight) of methoxypolyethylene glycol monomethacrylate (number of ethylene oxide units added on average per molecule, 23), 123.4 g of a phosphate (A) of a mixture of mono- [2-hydroxyethyl) methacrylic acid phosphate ester and di- [ (2-hydroxyethyl) methacrylic acid], and 6.1 g of 3-mercaptopropionic acid, and a solution prepared by dissolving 11.9 g of ammonium persulfate in 67 g of water, respectively for 1.5 hours. After the mixture matured for 1 hour, a solution prepared by dissolving 2.6 g of ammonium persulfate in 15 g of water was added to the resulting mixture for 30 minutes, which was then ripened at the same temperature (80 ° C) for 1.5 hours After the maturation of the mixture ended, the mixture was neutralized to pH 6.0 by adding a 32% aqueous solution of sodium hydroxide dropwise to obtain an R-2 polymer having a weight average molecular weight of 36000 (coefficient reaction: 99%).

The phosphate (A) used in this example is obtained by the following production process. A reactor was charged with 200 g of 2-hydroxyethyl methacrylate and 36.0 g of 85% phosphoric acid (H3PO4). To the mixture was gradually added 89.1 g of phosphorus pentoxide (P2O5) with cooling of the mixture such that the temperature did not exceed 60 ° C. After the addition was completed, the temperature reaction was adjusted to 80 ° C to perform the reaction for 6 hours and the reaction solution was cooled to obtain phosphate (A). In some of the following production examples, phosphate (A) was used.

Production Example (A-1)

A glass reactor (four-mouth flask) equipped with an agitator was charged with 346 g of water, the atmosphere in the reactor was replaced with nitrogen with stirring, and the temperature of the water was raised to 80 ° C under a nitrogen atmosphere. Two solutions were added dropwise to the water, that is, a mixture prepared by mixing 391 g (effective content, 60.8% by weight; water content, 35% by weight) of methoxypolyethylene glycol monomethacrylate (number of units of ethylene oxide added on average per molecule, 23), 64.9 g of a phosphate (A) having a stress mixture of mono- [2-hydroxyethyl methacrylic acid] phosphate and phosphate esters of di- [(2-hydroxyethyl) methacrylic acid], 43.2 g of methacrylic acid and 4.9 g of 3-mercaptopropionic acid, and a solution prepared by dissolving 14.6 g of ammonium persulfate in 83 g of water, respectively for 1.5 hours After the mixture was ripened for 1 hour, a solution prepared by dissolving 4.2 g of ammonium persulfate in 24 g of water for 30 minutes was added dropwise to the resulting mixture, which was then ripened at the same temperature ( 80 ° C) for 1.5 hours. After the maturation of the mixture was finished, the mixture was neutralized to pH 6.0 by dropping a 32% aqueous solution of sodium hydroxide to obtain an A-1 polymer having a weight average molecular weight of 42000 (coefficient reaction: 100%).

Polymer No.

Production Example (A-2)

A polymer A-2 was prepared in the same manner as for polymer A-1, with the exception that the 5 monomers shown in Table 1 were used in the proportion of Table 1.

The proportion of monomeric load, etc., is shown together. in the production examples of Table 1.

Table 1

10

Loaded material Proportion of

pH

monomer 3 in Pm / Mn

during

all Pm

the

monomers (% in

Type (top row) / load ratio (row

reaction

weight)

central:% in mol), (bottom row:% by weight) Monomer Monomer Monomer Monomer 1 2 3 4

MEPEG

--MAA

E (23)

R-1 0 2.0 48000 1.51

25 --75 81 --19 MEPEG-HEMA-HEMA

-

E (23) MPE MPE

R-2 5.7 1.1 36000 1.29

40 4218 - 76 24 - MEPEG-HEMA-HEMA

MAA

E (23) MPE MPE

A-1 3.0 1.5 42000 1.40

25 14 6 55 74 13 13 MEPEG-HEMA-HEMA

MAA

E (23) MPE MPE

A-2 4.9 1.2 38000 1.28

40 35 15 10 77.5 21 1.5

The symbols in the table are as indicated below. In the table, the numbers in brackets are the numbers of EO units added above the average per molecule (this is used hereafter in this document).

15 • MEPEG-E: -Methoxypolyethylene glycol monomethacrylate

•

 MAA: Methacrylic Acid

•

HEMA-MPE: 2-hydroxyethyl methacrylate monophosphate

twenty

•

HEMA-DPE: 2-hydroxyethyl methacrylate diphosphate

•

 Pm: Weight average molecular weight

25 Production Examples (B-1 and B-2)

Polymers B-1 and B-2 were prepared in the same manner as for polymer R-2, with the exception that the monomers shown in Table 2 were used in the proportions of Table 2. The proportion of monomeric charge , etc. in the production examples they are shown together in Table 2.

30

Table 2

Polymer No.

Raw material to be loaded pH during the reaction P.m

Type (upper row) / load ratio (lower row:% in mol)

Monomer 1

Monomer 2 Monomer 3

B-l

MEPEG-E (9) HEMA-MPE HEMA-DPE 1.1  24000

75

 17 8

B-2

MEPEG-E (23) HEMA-MPE HEMA-DPE 1.2  39000

75

 17 8

<Test example> Concrete test

5

(1) Cement Dispersants

Polymers, etc. in Tables 1 and 2 they were used in the proportions by weight of Tables 4 to 6 to prepare cement dispersants. Each of the cement dispersants was used in an assay on the preparation of 10 concrete compounds as shown in Table 3. The results are shown in Tables 4 to 6. S-1 is sucrose (retardant).

(2) Concrete Compositions

15 Concrete compositions are as shown in Table 3. Table 3

Composition

A / C (% by weight) Unit Quantity (kg / m3) Amount of air (% by volume)

TO

C1 C2 S1 S2 S3 G

I

30 175 583  - 304 191 266 868 3.0

II

30 175 - 583 307 191 269 868 3.0

III

Four. Five 170 378  - 335 210 292 933 4,5

20 The materials used in Table 3 are as follows:

A: Deionized water C1: Normal Portland cement (mixture of normal Portland cement manufactured by Taiheiyo Cement Corporation and 25 normal Portland cement manufactured by Sumitomo Osaka Cement Co., Ltd. (1: 1)). C2: Low thermal Portland cement (low thermal Portland cement manufactured by Taiheiyo Cement Corporation).

30 S1: Fine aggregate, earth sand from Kodama-gun, Saitama Pref. (Density: 2.62 g / cm3) S2: Fine aggregate, crushed sand from Aso-gun, Tochigi Pref. (Density: 2.62 g / cm3) S3: Fine aggregate, crumb sand (moderate size) from Kimitsu, Ciba Pref. (density: 2.61 g / cm3)

35

G: Coarse aggregate, crushed stone from 2005 by Aso-gun, Tochigi Pref. (Density: 2.70 g / cm3)

(3) Preparation of Concrete

The concrete was prepared using a two-axis forced mixer manufactured by IHI with the following conditions:

5 concrete capacity: 30 liters, stirring time, dry mix for 10 seconds, and 90 seconds after pouring the kneading water. In the case of Compositions I and II, the amount of the dispersant (polymer composition) to be added was controlled such that the value of the settlement flow was 600 to 680 mm after 30 minutes of preparation. In the case of Composition III, the amount of cement dispersant that was added was controlled so that the settlement was just 20 to 22 cm.

10 after preparation. The settlement flow value in Compositions I and II is the mean of the maximum settlement flow value and a settlement flow value measured in a perpendicular direction, at a length of 1/2 of the segment giving the maximum value, in the address in which the maximum value was obtained. The concrete settlement flow test was performed in the same manner as in JIS A 1150, with the exception that each layer was uniformly inserted 5 times with a compaction rod (maximum dimension

15 of the coarse aggregates (G), 20 mm; concrete temperature from 20 to 22ºC; sample compaction procedure: the sample was compacted into three divided layers). The settlement value in Composition III was examined according to a settlement test (document JIS A 1101). In addition, the amount of air in the cement (JIS A 1128) was controlled so that the amount of air entering was 3.0% by volume or less for Compositions I and II or 4.0 to 5 , 0% by volume for Composition III by adding an agent

20 antifoam.

(4) Concrete Evaluation

The prepared concrete to which dispersant had been added was measured by its fluidity (settlement flow or

25 settlement) just after kneading and 15 or 30 minutes after kneading and by its fluidity (settlement flow or settlement) after kneading with a shovel. The results are shown in Tables 4 to 6. Table 4 shows the results of Composition I (normal Portland cement, A / C = 30% by weight), Table 5 shows the results of Composition II (Portland cement low thermal, A / C = 30% by weight), and Table 6 shows the results of Composition III (normal Portland cement, A / C = 45% by weight). In the

Compositions I and II, settlement flow was measured for high strength concrete, and in Composition III, settlement was measured for general strength concrete.

Table 4

Dispersant Preparation Ratio (weight ratio)

Concrete test (Composition I)

Just after kneading

After 15 minutes

Dosage (%)

Settlement flow (mm) Settlement flow (mm) Difference in Settlement Flow (mm)

Test Example 1

R-1 / B-2 = 70/30 0,180 480 620 +140

Test Example 2

R-2 / B-2 = 70/30 0,170 620 610 -10

Test Example 3

A-1 / B-2 = 70/30 0.174 610 625 +15

Test Example 4

A-2 / B-2 = 70/30 0.172 620 615 -5

Test Example 5

A-1 / B-1 / B-2 / S-1 = 30/30/30/10 0.352  600 615 +15

In Table 4, the amount of additive is the amount (solid content,% by weight) of the dispersant with respect to the weight of the cement (this is used hereafter).

Table 5

Dispersant Preparation Ratio (weight ratio)

Concrete test (Composition II)

Just after kneading

Just after kneading

After 15 minutes

 Dosage (%)

Settlement flow (mm) Settlement flow (mm) difference in settlement flow (mm)

Test Example 6

R-1 / B-2 = 70/30 0.171  670 640 -30

Test Example 7

R-2 / B-2 = 70/30 0.171  540 650 +110

Test Example 8

A-1 / B-2 = 70/30 0.171 650 645 -5

Test Example 9

A-2- / B-2 = 70/30 0.171  630 645 +15

Test Example 10

A-1 / B-1 / B-2 / S1 = 30/30/30/10 0.345  650 645 -5

Table 6

Dispersant Preparation Ratio (weight ratio)

Concrete test (Composition III)

Right after the reaction

After 30 minutes

Dosage (%)

settlement (cm) settlement (cm) difference in settlement (cm)

Test Example 11

A-2 / B-1 / B-2 / S-1 = 30/30/30/10 0.235  2,1,0 20.0 -1.0

Test Examples 1 and 6 are tests on dispersants using acid-based polymers

5 polycarboxylic acid, and Test Examples 3 and 8, Test Examples 4 and 9 and Test Examples 5, 10 and 11 are assays on dispersants using the polymers of the present invention. In all test examples, the phosphate based polymer was used simultaneously.

It can be seen that in the test examples using the polymers of the present invention, any

10 composition just after kneading and 15 minutes or 30 minutes after kneading shows less change in fluidity and also shows its necessary effect on hydraulic compositions with a wide range of formulations (water / cement ratio) and materials (cement type) . On the other hand, it can be seen that the settling flow value of Composition I (Table 4) using normal Portland cement with A / C = 30% by weight in the system in which polycarboxylic acid based polymer was used simultaneously ( Test example

15 1) It is small just after kneading and tends to increase 15 minutes after kneading. It can be seen that in Test Example 7, the settling flow value of Composition II (Table 5) using low thermal Portland cement with A / C = 30% by weight is small just after kneading and tends to increase 15 minutes after kneading.

The polymer R-2 according to the present invention, and A-2 without using monomer 4, has almost the same weight average molecular weight and Pm / Mn. Test Examples 4 and 2 using the respective polymers in Composition I are not significantly different from those in the settlement flow 15 minutes after kneading, while Test Examples 9 and 7 using Composition II are significantly different with respect to the difference in settlement flow 15 minutes after settlement. From this result,

It can be seen that the polymers of the present invention are superior in general versatility for different hydraulic powders in composition and material.

Test Example 12

Polymer B-3 was prepared according to Production Example (R-1) using 40% methoxypolyethylene glycol monomethacrylate in mol (number of ethylene oxide units added on average per molecule: 5 23) as monomer 1 and 60% methacrylic acid in mol as monomer 4.

Polymer B-3 was used instead of polymer B-2 in Test Example 3 and evaluated in the same way. The hydraulic composition 15 minutes after kneading has more viscosity than in Test Example 3, but it is estimated that with respect to settlement flow, almost the same result is obtained as in the Example of

10 essay 3.

Claims (13)

1. A dispersant for a hydraulic composition, comprising a polymer obtained by copolymerization of monomer 1 represented by the following formula (1), monomer 2 represented by the 5 following formula (2), monomer 3 represented by the following formula (3) and monomer 4 represented by the following formula (4), at pH 7 or less, in which the proportion (Pm / Mn) of molecular weight Average by weight (Pm) with respect to the number average molecular weight (Mn) of the polymer is 1.0 to 2.6: image 1 In which each of R1 and R2 represents a hydrogen atom or a methyl group, R3 represents a hydrogen atom or - (CH2) q (CO) pO (AO) rR4 in which AO represents an oxyalkylene group having from 2 to 4 carbon atoms or an oxystyrene group, p represents a number of 0 or 1, q represents a number from 0 to 2, p and q are not simultaneously 0, r represents the molar number of AO units added over the mean by molecule and 15 represents a number from 3 to 300, and R4 represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms; image 1 In which R11 represents a hydrogen atom or a methyl group, R12 represents an alkylene group having 2 to 12 carbon atoms, m1 represents a number from 1 to 30, and each of M3 and M4 represents an atom of hydrogen, an alkali metal or an alkaline earth metal; image 1 in which each of R13 and R15 represents a hydrogen atom or a methyl group, each of R14 and R16 represents an alkylene group having 2 to 12 carbon atoms, each of m2 and m3 represents a number of 1 at 30, and M5 represents a hydrogen atom, an alkali metal or an alkaline earth metal; Y image 1 wherein each of R17 to R19 represents a hydrogen atom or a methyl group, (CH2) 5COOM7 being optionally combined with COOM6 or another (CH2) 5COOM7 to form an anhydride without M6 and M7 in the groups, s represents a number from 0 to 2, and each of M6 and M7 represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group, an alkylammonium group, a substituted alkylammonium group, an alkyl group, a hydroxyalkyl group or an alkenyl group .

2.

The dispersant for a hydraulic composition according to claim 1, wherein the polymer is obtained by copolymerizing the monomers, wherein the proportion of monomer 1 is from 60 to 98% by weight, the total proportion of monomers 2 and 3 is 1 to 39% by weight, and the proportion of monomer 4 is 1 to 39% by weight, based on the total monomers that constitute the polymer.

3.

The dispersant for a hydraulic composition according to claim 1 or 2, wherein the weight average molecular weight (Pm) of the polymer is 15,000 to 80,000.

Four.

The dispersant for a hydraulic composition according to any one of claims 1 to 3, further comprising a retention agent.

5.

A hydraulic composition comprising the dispersant of a hydraulic composition of any one of claims 1 to 4, a hydraulic powder and water, wherein the hydraulic powder is at least one member selected from the group consisting of normal Portland cement, moderately thermal Portland cement, low thermal Portland cement and blast furnace slag cement.

6.

A hydraulic composition comprising the dispersant for a hydraulic composition of any one of claims 1 to 4, a hydraulic powder, fine aggregates, coarse aggregates and water, wherein the weight ratio of water / hydraulic powder is from 10 to 60 %, and the unit amount of water is 120 to 185 kg / m3.

7.

A process for producing a phosphate-based polymer, which comprises the copolymerization of monomer 1 represented by formula (1) in claim 1, monomer 2 represented by formula

(2) in claim 1, the monomer 3 represented by the formula (3) in claim 1, and the monomer 4 represented by the formula (4) in claim 1, at pH 7 or less in the presence of an agent of chain transfer

8.

The process for producing a phosphate based polymer according to claim 7, wherein the ratio (Pm / Mn) of the weight average molecular weight (Pm) with respect to the number average molecular weight (Mn) of the polymer obtained is 1 , 0 to 2.6.

9.

The process for producing a phosphate based polymer according to claim 7 or 8, wherein the weight average molecular weight (Pm) of the polymer obtained is 15,000 to 80,000.

10.

The process for producing a phosphate based polymer according to any one of claims 7 to 9, wherein the chain transfer agent is a thiol-based chain transfer agent.

eleven.

The process for producing a phosphate based polymer according to any one of claims 7 to 10, wherein the proportion of monomer 1 is 60 to 98% by weight, the total proportion of monomers 2 and 3 is 1 to 39 % by weight, and the proportion of monomer 4 is 1 to 39% by weight, based on the total monomers used in the polymer.

12.

The process for producing a phosphate based polymer according to any one of the

claims 7 to 11, wherein the proportion of monomer 3 is 1 to 15% by weight based on the total monomers used in the polymer.

13.

Use of the polymer of any one of claims 1 to 4 or a polymer obtained in the

The method of any one of claims 7 to 12 in the form of a dispersant for a hydraulic composition.