JP2007092061A - Method for producing phosphate polymer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a dispersant for a hydraulic composition imparting an excellent dispersing effect and viscosity reducing effect to the hydraulic composition, in a practical industrial level with a good reproducibility. <P>SOLUTION: The method for producing the phosphate polymer suitable for the dispersant for a hydraulic composition comprises a copolymerization of a specific monomer 1 having a polyoxyalkylene group, a phosphoric monoester monomer 2, and a phosphoric diester monomer 3 in a polymerization solvent having 0.01-4.0 mg/kg of dissolved oxygen concentration at 25°C and setting pH at less than 7. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a phosphate ester polymer and a method for producing a dispersant for a hydraulic composition. Furthermore, the present invention relates to a phosphate ester polymer, a dispersant for a hydraulic composition containing the same, and a hydraulic composition containing the same.

  Among the admixtures for hydraulic compositions, there is one called a high-performance water reducing agent having a large fluidity-imparting effect. Typical examples include naphthalene sulfonic acid formaldehyde condensate salt (naphthalene type), melamine sulfonic acid formaldehyde condensate salt (melamine type), polycarboxylic acid type having a polyoxyalkylene chain, and the like.

  In recent years, concrete, which is a typical hydraulic composition, has become more durable. For example, the amount of water used in concrete has been reduced to increase its strength. Are also expected to increase. In order to reduce the amount of water, it is mainstream to use a polycarboxylic acid-based water reducing agent that is excellent in water reduction and fluidity retention. However, as the amount of water decreases, fresh concrete viscosity (hereinafter also referred to as concrete viscosity) increases, and there is a problem that workability and workability such as pumping, driving and filling into a formwork are lowered. This viscosity increase problem has not been sufficiently solved even with a polycarboxylic acid-based water reducing agent, and an additive having a higher concrete viscosity reducing effect is desired.

For example, Patent Document 1 discloses a method for producing a cement dispersant by radical polymerization reaction in the presence of a solvent. Polyalkylene glycol (meth) acrylate and / or polyalkylene glycol (meth) allyl ether and (meth) acrylic acid and A copolymer produced by reacting maleic acid with a polymerization solvent having a dissolved oxygen concentration of 0.01 to 4.0 mg / kg is disclosed, and Patent Document 2 discloses a polyalkylene glycol chain. What contains the polymer of the monoester or monoether which has this, and the monomer which has an unsaturated bond and a phosphoric acid group is disclosed. Patent Document 3 discloses a method of copolymerizing unsaturated polyalkylene glycol and unsaturated polycarboxylic acid at a dissolved oxygen concentration of 5 ppm.
JP 2001-146447 A JP 2000-327386 A JP 2001-31722 A

  However, the methods of Patent Documents 1 to 3 are all related to a so-called polycarboxylic acid polymer, and have an excellent dispersion effect or viscosity reduction effect for a hydraulic composition containing hydraulic powder. Furthermore, a phosphoric acid ester-based polymer that can provide both of these excellent effects and can be used as a dispersant for a hydraulic composition with good performance is stable with good reproducibility at an industrially practical level (depending on the production lot). No mention is made of a process that can be produced with a small variation in molecular weight.

  An object of the present invention is to provide a copolymer that can impart an excellent dispersion effect and viscosity reduction effect to a hydraulic composition containing a hydraulic powder, and serves as a dispersant for a hydraulic composition with good performance. An object is to provide a method that can be produced stably and reproducibly (with little variation in molecular weight depending on the production lot) at an industrially practical level.

  The present invention relates to a monomer 1 represented by the following general formula (1) (hereinafter referred to as monomer 1) and a monomer 2 represented by the following general formula (2) (hereinafter referred to as monomer 2). And a monomer 3 represented by the following general formula (3) (hereinafter referred to as monomer 3) is a polymerization solvent having a dissolved oxygen concentration at 25 ° C. of 0.01 to 4.0 mg / kg. In particular, the present invention relates to a method for producing a phosphate ester polymer copolymerized at pH 7 or lower.

[Wherein R ¹ and R ² are each a hydrogen atom or a methyl group, R ³ is a hydrogen atom or —COO (AO) _n X, AO is an oxyalkylene group or oxystyrene group having 2 to 4 carbon atoms, n is It is the average added mole number of AO, the number of 3-200, X represents a hydrogen atom or a C1-C18 alkyl group. ]

[Wherein, R ⁴ represents a hydrogen atom or a methyl group, R ⁵ represents an alkylene group having 2 to 12 carbon atoms, m1 represents a number of 1 to 30, and M represents a hydrogen atom, an alkali metal or an alkaline earth metal. ]

[Wherein R ⁶ and R ⁸ are each a hydrogen atom or a methyl group, R ⁷ and R ⁹ are each an alkylene group having 2 to 12 carbon atoms, m2 and m3 are each a number from 1 to 30 and M is hydrogen. Represents an atom, an alkali metal or an alkaline earth metal. ]

  The present invention also relates to a monomer 1 represented by the general formula (1), a monomer 2 represented by the general formula (2), and a single monomer represented by the general formula (3). It is related with the manufacturing method of the dispersing agent for hydraulic compositions which copolymerizes the body 3 at pH 7 or less in the polymerization solvent whose dissolved oxygen concentration in 25 degreeC is 0.01-4.0 mg / kg.

  The present invention also relates to the monomer 1 represented by the general formula (1), the monomer 2 represented by the general formula (2), and the monomer represented by the general formula (3). 3 is a phosphate ester polymer (hereinafter, referred to as “polyester”) obtained by copolymerization at 25 ° C. in a polymerization solvent having a dissolved oxygen concentration of 0.01 to 4.0 mg / kg at a pH of 7 or less. The first phosphate ester polymer).

In addition, the present invention provides a phosphor obtained by copolymerizing the following (X) and (Y) at a pH of 7 or less in a polymerization solvent having a dissolved oxygen concentration at 25 ° C. of 0.01 to 4.0 mg / kg. The present invention relates to an acid ester copolymer (hereinafter referred to as a second phosphate ester polymer).
(X) Monomer 1 represented by the general formula (1).
(Y) Phosphate ester obtained by reacting an organic hydroxy compound represented by the following general formula (4) with a phosphorylating agent.

[Wherein, R ¹⁰ represents a hydrogen atom or a methyl group, R ¹¹ represents an alkylene group having 2 to 12 carbon atoms, and m4 represents a number of 1 to 30. ]

  Moreover, this invention relates to the dispersing agent for hydraulic compositions containing the phosphate ester type polymer of the said invention. Furthermore, this invention relates to the hydraulic composition containing hydraulic powder, water, and the dispersing agent for hydraulic compositions of the said invention.

  According to the present invention, even when a monomer containing a phosphate ester having a large amount of diester is used, a phosphate ester type suitable as a dispersant for a hydraulic composition capable of suppressing high molecular weight and performance degradation due to crosslinking. Provided is a method capable of stably producing a polymer with good reproducibility. Moreover, the production method of the present invention does not impair the properties of the phosphate ester polymer as a dispersant for a hydraulic composition. The dispersant containing the phosphate ester polymer obtained by the production method of the present invention can impart an excellent dispersion effect and viscosity reduction effect to a hydraulic composition containing hydraulic powder, and has performance. It is good.

<< Production Method of Phosphate Ester Polymer >>
In the present invention, monomer 1, monomer 2 and monomer 3 are copolymerized at a pH of 7 or less in a polymerization solvent having a dissolved oxygen concentration at 25 ° C. of 0.01 to 4.0 mg / kg. The present invention relates to a method for producing a phosphate ester polymer. Any of the phosphate ester polymers of the present invention can be produced by this production method. It is also preferable to use a mixed monomer containing monomer 2 and monomer 3.

  The present inventors have found that a polymer derived from a specific phosphate ester is useful for reducing the viscosity of a hydraulic composition which is one of the problems of the present invention. Furthermore, the manufacturing method suitable for industrialization of this polymer was discovered.

  Hereinafter, the manufacturing method of the phosphate ester type polymer using the monomers 1-3 is demonstrated.

  Industrially, the phosphate ester monomer is usually obtained as a mixture containing a monoester (monomer 2) and a diester (monomer 3). Among these, since diesters are likely to have a high molecular weight (gelation) by crosslinking, such a mixture is restricted in production in fields using the properties, for example, thickeners, adhesives, coatings, etc. Can be used suitably without receiving much. On the other hand, for admixtures for hydraulic compositions (dispersants, water reducing agents, etc.), copolymers containing phosphate groups are preferred because of their excellent adsorptive power to hydraulic substances, but dispersibility and viscosity are reduced by increasing the molecular weight. This is not preferable from the viewpoint of handleability. However, it is industrially disadvantageous to separate the monoester form and the diester form from the mixture of phosphate esters as raw materials from the application and economical properties of the hydraulic composition. In the production method of the present invention, the monomer 1, the phosphate ester monomer 2 and the monomer 3 have a dissolved oxygen concentration of 0.01 to 4.0 mg / kg at 25 ° C. Copolymerization is carried out at a pH of 7 or less in a polymerization solvent. By this production method, a polymer can be stably produced with good reproducibility without occurrence of cross-linking (high molecular weight, gelation) even when a raw material containing a diester is used, and for a hydraulic composition of a phosphate ester polymer. This production method is extremely advantageous in the field of hydraulic compositions because it can maintain excellent performance as a dispersant.

  The phosphoric acid ester polymer according to the present invention is represented by the monomer 1 having an oxyalkylene group represented by the general formula (1) and the general formulas (2) and (3) having a phosphoric acid group. It is a polymer obtained by copolymerizing the monomers 2 and 3 to be produced.

  Preferable monomers 1 to 3 used in the present invention are as follows, and commercially available products and reaction products can also be used.

[Monomer 1]
For monomer 1, R ³ in general formula (1) is preferably a hydrogen atom, and AO is preferably an oxyalkylene group having 2 to 4 carbon atoms, and more preferably contains an ethyleneoxy group (hereinafter referred to as EO group). The EO group is 70 mol% or more, more preferably 80 mol% or more, more preferably 90 mol% or more, and particularly preferably all AO is an EO group in the total AO. X is preferably a hydrogen atom or an alkyl group having 1 to 18, more preferably 1 to 12, further 1 to 4, and 1 or 2 carbon atoms, and particularly preferably a methyl group. Specific examples include ω-methoxypolyoxyalkylene methacrylate and ω-methoxypolyoxyalkylene acrylate, and ω-methoxypolyoxyalkylene methacrylate is more preferable. Here, n in the formula (1) is the average added mole number. In terms of dispersibility of the polymer in the hydraulic composition and the effect of imparting viscosity, n is 3 to 200, preferably 4 to 120. In addition, AO is different among n repeating units on average, and random addition, block addition, or a mixture thereof may be included. AO can also contain a propyleneoxy group etc. besides EO group.

[Monomer 2]
Examples of the monomer 2 include phosphoric acid monoesters of organic hydroxy compounds. Specific examples include polyalkylene glycol mono (meth) acrylate acid phosphates. For example, phosphoric acid mono-[(2-hydroxyethyl) methacrylic acid] ester, phosphoric acid mono-[(2-hydroxyethyl) acrylic acid ester] and the like can be mentioned. Among these, phosphoric acid mono-[(2-hydroxyethyl) methacrylic acid] ester is preferable from the viewpoint of ease of production and product quality stability.

[Monomer 3]
Examples of the monomer 3 include phosphoric acid diesters of organic hydroxy compounds. Specific examples include polyalkylene glycol di (meth) acrylate acid phosphoric acid diester. Examples include phosphoric acid di-[(2-hydroxyethyl) methacrylic acid] ester, phosphoric acid di-[(2-hydroxyethyl) acrylic acid] ester, and the like. Among these, di-[(2-hydroxyethyl) methacrylic acid] ester phosphate is preferable from the viewpoint of ease of production and quality stability of the product.

  Any of the monomers 2 and 3 may be a salt, and may be an alkali metal salt, alkaline earth metal salt, ammonium salt, alkylammonium salt or the like of these compounds.

  M1 of the monomer 2 and m2 and m3 of the monomer 3 are each preferably 1 to 20, more preferably 1 to 10, and particularly preferably 1 to 5.

  Moreover, in the manufacturing method of this invention, the mixed monomer containing the monomer 2 and the monomer 3 can be used.

  As the mixed monomer containing the monomer 2 and the monomer 3, a commercial product containing a monoester and a diester can be used. For example, Phosmer M, Phosmer PE, Phosmer P ( Unichemical), JAMP514, JAMP514P, JMP100 (all Johoku Chemical), light ester P-1M, light acrylate P-1A (all Kyoeisha Chemical), MR200 (Daiha Chemical), Kayamar (Nippon Kayaku), Ethyleneglycolmethacrylate phosphate (Aldrich reagent).

Moreover, the mixed monomer containing the monomer 2 and the monomer 3 is, for example, phosphorylated with an organic hydroxy compound represented by the general formula (4), phosphoric anhydride (P ₂ O ₅ ), orthophosphoric acid, and the like. It can also be produced as a reaction product by reacting an agent and water at a predetermined charge ratio.

  That is, a phosphoric acid ester obtained by reacting the organic hydroxy compound represented by the general formula (4) with a phosphorylating agent can be used.

  Examples of the phosphorylating agent include orthophosphoric acid, phosphorus pentoxide (anhydrous phosphoric acid), polyphosphoric acid, phosphorus oxychloride and the like, and orthophosphoric acid and phosphorus pentoxide are preferable. These may be used alone or in combination of two or more. Further, the phosphorylating agent (Z) described later is also preferable. In this invention, the quantity of the phosphorylating agent at the time of making an organic hydroxy compound and a phosphorylating agent react can be determined timely according to the target phosphate ester composition.

  Monomers 2 and 3 are phosphoric acid esters of monomers having unsaturated bonds and hydroxyl groups, and the above-mentioned commercially available products and reaction products include monoester (monomer 2) and diester ( It has been confirmed that it contains compounds other than monomer 3). These other compounds are considered to be a mixture of polymerizable and non-polymerizable compounds, but in the present invention, such a mixture (mixed monomer) can be used as it is.

The contents of monomers 2 and 3 in the mixed monomer can be calculated based on ³¹ P-NMR measurement results.
< ³¹ P-NMR measurement conditions>
・ Inverse-gated-decoupling method
・ Measurement range: 6459.9Hz
・ Pulse delay time 30sec
Observation data point 10336
・ Pulse width (5.833μsec) 35 ° pulse ・ Solvent CD ₃ OH (deuterated methanol) (30% by weight)
・ Number of integration 128

  Under these conditions, the signal of the obtained chart belongs to the following compound, so that it is possible to determine the relative quantitative ratio from the area ratio.

For example, when the organic hydroxy compound is a phosphorous oxide of “2-hydroxyethyl methacrylate”, it can be assigned as follows.
・ 1.8ppm to 2.6ppm: phosphoric acid ・ 0.5ppm to 1.1ppm: Monomer 2 (monoester)
-0.5 ppm to 0.1 ppm: monomer 3 (diester form)
-1.0 ppm to -0.6 ppm: Triester form -11.1 ppm to -10.9 ppm, -12.4 ppm to -12.1 ppm: Pyrophosphate monoester --12.0 ppm to -11.8 ppm: Pyrophosphate diester -11.2 ppm to -11.1ppm: pyrophosphoric acid, other peaks: unknown

  In the present invention, the phosphoric acid content in the mixed monomer is quantified to determine the ratio of the monomer 2 and the monomer 3 in the mixed monomer. Specifically, the calculation is performed as follows.

The absolute amount (% by weight) of the phosphoric acid content in the sample is determined by gas chromatography. ^Since the relative molar ratio of phosphoric acid, mono-isomer, and di-isomer in the sample can be obtained from the ³¹ P-NMR result, the absolute amount of mono-isomer and di-isomer is calculated based on the absolute amount of phosphoric acid.

[Phosphoric acid content]
The conditions for gas chromatography are as follows.
Sample: Methylation with diazomethane Example) Methylation by adding 1 to 1.5 cc of diazomethane in diethyl ether to 0.1 g of sample Column: Ultra ALLOY, 15 m × 0.25 mm (inner diameter) × 0.15 μmdf
Carrier gas: He, split ratio 50: 1
Column temperature: 40 ° C. (5 min) (hold) → 10 ° C./min (temperature rise) → 15 min after reaching 300 ° C. Hold inlet temperature: 300 ° C.
Detector temperature: 300 ° C
Under the above conditions, a phosphate-derived peak is detected around 9 minutes, and the phosphate content in the unknown sample can be calculated by a calibration curve method.

[Content of mono- and di-form]
Based on the phosphoric acid content determined above, the total amount of mono- and di-isomers in the reagents used in Examples and the like described below was calculated as follows. The pyrophosphoric acid monoester, pyrophosphoric acid diester, and pyrophosphoric acid were calculated by assigning the decomposition products to phosphoric acid and the monoester compound in consideration of hydrolysis during the polymerization process.
・ Hosmer M: 81.8% by weight

When the charge molar ratio of the monomer is calculated based on the breakdown of the mono- and di-forms from the above results and the NMR results, it is as follows in the case of Example 1-1.
Ω-methoxypolyethyleneglycol monomethacrylate (addition mole number of ethylene oxide 9: NK ester M90G made by Shin-Nakamura Chemical) = 34 mol%
-Mono (2-hydroxyethyl) phosphate ester = 46 mol%
-Di- (2-hydroxyethyl) phosphate ester = 20 mol%

  From the viewpoint of fluidity and viscosity reduction, it is better to use a mixture of phosphate esters containing a large amount of monoester, but even if it contains a large amount of diester, By controlling the polymerization molar ratio, fluidity and viscosity reduction can be adjusted.

  In the copolymerization of the monomers, the molar ratio between the monomer 1 and the monomers 2 and 3 is as follows: monomer 1 / (monomer 2 + monomer 3) = 5/95 to 95/5 Furthermore, 10/90 to 90/10 are preferable. The molar ratio of monomer 1, monomer 2 and monomer 3 is as follows: monomer 1 / monomer 2 / monomer 3 = 5 to 95/3 to 90/1 to 80 / 5 to 96/3 to 80/1 to 60 (however, the total is 100) is preferable. In addition, about the monomer 2 and the monomer 3, the molar ratio and mol% shall be calculated based on an acid type compound (hereinafter the same).

Moreover, in this invention, the ratio of the monomer 3 can be 1-60 mol% in all the monomers used for reaction, and also can be 1-30 mol%.
Further, the molar ratio of the monomer 2 and the monomer 3 can be set to monomer 2 / monomer 3 = 99/1 to 4/96, and more preferably 99/1 to 5/95.
Since the monomer raw material containing the monomer 3 in such a range is generally expected to be gelled, it is usually not suitable as a raw material for producing a polymer for a dispersant for a hydraulic composition. it is conceivable that. However, in the present invention, gelation is suppressed by reacting the monomer at a pH of 7 or less in a polymerization solvent having a dissolved oxygen concentration of 0.01 to 4.0 mg / kg at 25 ° C., which is hydraulic. A phosphate ester polymer suitable as a dispersant for the composition can be produced stably and reproducibly at an industrially practical level.

Hereinafter, more preferable production conditions will be described from the viewpoints of gelation suppression, adjustment of a suitable molecular weight, and performance design of a dispersant for hydraulic composition. From this point of view, in the present invention, at the time of copolymerization, 4 mol% or more, further 6 mol% or more, particularly 8 mol% or more of the chain transfer agent is added to the total number of moles of monomers 1 to 3. It is preferable to use it. Further, the upper limit of the amount of chain transfer agent used is preferably 100 mol% or less, more preferably 60 mol% or less, still more preferably 30 mol% or less, particularly preferably based on the total number of moles of monomers 1 to 3. May be 15 mol% or less. For more details,
(1) When n of monomer 1 is 3 to 30,
(1-1) When the molar ratio of the monomer 2 and the monomer 3 in the monomers 1 to 3 is 50 mol% or more, the chain transfer agent is 6 to It is preferable to use 100 mol%, in particular 8 to 60 mol%,
(1-2) When the molar ratio of the monomer 2 and the monomer 3 in the monomers 1 to 3 is less than 50 mol%, the chain transfer agent is 4 to 4 with respect to the monomers 1 to 3. It is preferable to use 60 mol%, in particular 5 to 30 mol%,
(2) When n of monomer 1 exceeds 30, the chain transfer agent is preferably used in an amount of 6 to 50 mol%, particularly 8 to 40 mol%, based on monomers 1 to 3.

  In the production method of the present invention, the reaction rate of the monomers 2 and 3 is preferably 60% or more, more preferably 70% or more, further 80% or more, further 90% or more, and particularly preferably 95% or more. The amount of transfer agent used can be selected from this viewpoint. Here, the reaction rate of the monomers 2 and 3 is calculated by the following equation.

In addition, the ratio (mol%) of the monomer 2 and the monomer 3 in the phosphorus-containing compound in the reaction system at the start of the reaction and at the end of the reaction can be calculated based on the measurement result of ¹ H-NMR. .

The first phosphate polymer of the present invention, by ¹ H-NMR under the following conditions, since the double bond derived from the monomer has disappeared, to monomeric 1,2,3 It is suggested that each have a derived unit.
[ ¹ H-NMR conditions]
A polymer dissolved in water and dried under reduced pressure is dissolved in deuterated methanol at a concentration of 3 to 4% by weight, and ¹ H-NMR is measured. The residual rate of double bonds is measured by an integrated value of 5.5 to 6.2 ppm. In addition, the measurement of ¹ H-NMR uses “Mercury 400 NMR” manufactured by Varian, the number of data points is 42052, the measurement range is 6410.3 Hz, the pulse width is 4.5 μs, the pulse waiting time is 10 S, and the measurement temperature is 25.0 ° C. Perform under conditions.

  That is, the first phosphate ester polymer of the present invention having Mw as described above has, as its constituent units, a constituent unit derived from monomer 1, a constituent unit derived from monomer 2, and monomer 3. Includes derived structural units. These structural units are structural units derived from the respective monomers incorporated into the polymer by cleavage of the ethylenically unsaturated bonds of the monomers 1, 2 and 3 and addition polymerization. The ratio of these structural units in the polymer depends on the charging ratio, and when the monomers used for copolymerization are only monomers 1 to 3, the molar ratio of each structural unit is the monomer charging molar ratio. It is thought that it is almost the same.

  From the viewpoint of expressing dispersibility, the content of unreacted monomer 2 and monomer 3 in the reaction product is 5 mol% or less based on the total amount of monomers 2 and 3 charged. Preferably, it is 3 mol% or less, more preferably 2 mol% or less.

  In the production of the phosphate ester polymer according to the present invention, in addition to the monomers 1 to 3, other monomers capable of copolymerization may be used. Examples of the other copolymerizable monomer include sulfonic acid or carboxylic acid having an unsaturated group, and salts thereof. For example, allyl sulfonic acid, methallyl sulfonic acid, alkali metal salt, alkaline earth metal salt, ammonium salt, or amine salt of any of these can be mentioned. In addition, acrylic monomers such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, and the like, and any one or more of alkali metal salts, alkalis Anhydrous compounds such as earth metal salts, ammonium salts, amine salts, methyl esters, ethyl esters and maleic anhydride may also be used. Furthermore, (meth) acrylamide, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, 2- (meth) acrylamide-2-metasulfonic acid, 2- (meth) acrylamide-2-ethanesulfonic acid, Examples include 2- (meth) acrylamide-2-propanesulfonic acid, styrene, styrenesulfonic acid and the like. The total proportion of monomers 1 to 3 in all monomers is preferably 30 to 100 mol%, more preferably 50 to 100 mol%, and particularly preferably 75 to 100 mol%. From the viewpoint of achieving the performance as a dispersant described in the phosphoric acid ester polymer, it is more than 95 mol% to 100 mol%, and more preferably 97 to 100 mol%.

  Other monomers that can be copolymerized can be contained in the mixed solution and introduced into the reaction system, introduced into the reaction system separately from the mixed solution, or further combined into the reaction system. Also, any of them may be used.

  The total amount of the monomers 1, 2, 3 in the reaction system and other monomers copolymerizable is preferably 5 to 80% by weight, more preferably 10 to 65% by weight in the reaction system, and 20 to 50% by weight. Is particularly preferred.

  In the production method of the present invention, the reaction temperature of the monomers 1 to 3 is preferably 40 to 100 ° C., more preferably 60 to 90 ° C., and the reaction pressure is 101.3 to 111.5 kPa (1 to 1.1 atm) as a gauge pressure. ) And 101.3-106.4 kPa (1-1.05 atm).

  In the production method of the present invention, the monomer solution containing the monomer 2 and / or the monomer 3 prepared with an appropriate solvent is preferably added to the monomer 1 in the presence of a predetermined amount of chain transfer agent. Are copolymerized at 25 ° C. or lower in a polymerization solvent having a dissolved oxygen concentration of 0.01 to 4.0 mg / kg. Moreover, you may use the other monomer, polymerization initiator, etc. which can be copolymerized.

  In the present invention, monomer 1, monomer 2, and monomer 3 are reacted at a pH of 7 or less in a polymerization solvent having a dissolved oxygen concentration at 25 ° C. of 0.01 to 4.0 mg / kg. In the present invention, the dissolved oxygen concentration at 25 ° C. is that at the start of the reaction, and the pH at 20 ° C. of the reaction solution collected during the reaction (from the start of the reaction to the end of the reaction) is the pH during the reaction. And Usually, the reaction may be started under conditions that clearly show that the pH during the reaction is 7 or less (monomer ratio, solvent, other components, etc.).

  When the reaction system is non-aqueous, it can be measured by adding an amount of water capable of measuring pH to the reaction system.

In the case of the monomers 1 to 3 that are the subject of the present invention, if the reaction is carried out under the conditions exemplified in the following (1) and (2), the pH during the reaction is usually adjusted under consideration of other conditions. It is considered to be 7 or less. Further, the pH may temporarily exceed 7 in the initial stage of the reaction as long as it does not affect the entire reaction, such as no gel is formed.
(1) A monomer solution having a pH of 7 or less containing all of monomers 1 to 3 is used for the copolymerization reaction of monomers 1 to 3.
(2) The copolymerization reaction of monomers 1 to 3 is started at pH 7 or less. That is, the reaction is started after the reaction system containing the monomers 1 to 3 is brought to pH 7 or lower.

In particular,
(I) The pH of the monomer solution containing the monomers 1 to 3 is adjusted to 7 or less to initiate the copolymerization reaction. (Ii) A monomer solution containing the monomers 1 to 3 (pH is arbitrary but preferably 7 or less) is added to the reaction system (the dissolved oxygen concentration at 25 ° C. is 0.01 to 4.0 mg / kg). A certain polymerization solvent).
(Iii) A monomer solution containing monomer 1 (pH is arbitrary but preferably 7 or less) and a monomer solution containing monomer 2 (pH is arbitrary but 7 or less are preferred). ) And a monomer solution containing monomer 3 (pH is arbitrary but preferably 7 or less) are separately prepared in a reaction system (dissolved oxygen concentration at 25 ° C. is 0.01 to 4.0 mg / kg). A certain polymerization solvent).
(Iv) The above is appropriately combined and the reaction is carried out in a polymerization solvent having a dissolved oxygen concentration at 25 ° C. of 0.01 to 4.0 mg / kg. For example, a part of a monomer solution containing the monomers 1 to 3 (pH is arbitrary but preferably 7 or less) is charged into the reaction system, and the remaining monomer solution is dropped into the reaction system. .

  In the above (iii) and (iv), it is necessary to control the dropping conditions of the monomer solution to be dropped so as not to deviate from the set monomer molar ratio. Moreover, in said (ii)-(iv), other reaction conditions are considered so that pH of the reaction system containing the dripped monomers 1-3 may be 7 or less, Preferably it is 4 or less.

  The pH of the reaction system can be adjusted with an inorganic acid (phosphoric acid, hydrochloric acid, nitric acid, sulfuric acid, etc.), NaOH, KOH, triethanolamine, or the like, if necessary.

As described above, in the present invention, in order to make the pH of the reaction system during the reaction 7 or less, the monomer solution containing at least one of the monomer 2 and the monomer 3 in the monomer solution used for the reaction. It is preferable that the pH of the body solution is 7 or less. The monomer solution having a pH of 7 or lower contains at least one of monomer 2 and monomer 3, and contains monomer 1, and further contains a chain transfer agent and other monomers. It may be. Here, the monomer solution containing the monomer 2 and / or the monomer 3 is preferably a water-containing system (that is, the solvent contains water) for pH measurement. May be measured by adding the required amount of water. From the viewpoint of uniformity of the monomer solution, prevention of gelation, and suppression of performance degradation, the pH is 7 or less, preferably 0.1 to 6, and more preferably 0.2 to 4.5. Monomer 1 is also preferably used as a monomer solution having a pH of 7 or less. This pH is at 20 ° C.

  The pH of the reaction system (polymerization system) before the reaction in which the monomer is finally charged is 20 ° C. from the viewpoint of stability when controlling the molecular weight of the polymer and ease of pH control during the reaction. It is preferably 6 or less, more preferably 5 or less, still more preferably 4 or less, and particularly preferably 2 or less. Preferably, the pH of the monomer solution containing monomer 2 and / or monomer 3 (pH of the reaction system at the start of the reaction), the pH of the reaction system during the reaction, and the pH of the reaction system at the end of the reaction are Both are 7 or less.

  In addition, when these monomers 1 to 3 are not used in a water-containing state (that is, dropped as a liquid component as they are), the pH of the polymerization system is inevitably 7 or less, and such a method is also suitable. The pH of the final polymerization system before neutralization is preferably 6 or less, more preferably 5 or less, further 4 or less, and particularly preferably 2 or less.

[Chain transfer agent]
The chain transfer agent has a function of causing a chain transfer reaction in radical polymerization (a reaction in which a growing polymer radical reacts with another molecule to move a radical active site). It is a substance to be added.

  The chain transfer agent should be used in an amount of 4 mol% or more, more 6 mol% or more, particularly 8 mol% or more based on the total number of moles of monomers 1 to 3 from the viewpoint of gelation suppression and adjustment of the preferred molecular weight. Is preferred.

  Examples of chain transfer agents include thiol chain transfer agents and halogenated hydrocarbon chain transfer agents, and thiol chain transfer agents are preferred.

As the thiol chain transfer agent, those having a —SH group are preferable, and in particular, the general formula HS—R—Eg (wherein R represents a hydrocarbon-derived group having 1 to 4 carbon atoms, and E is − OH, —COOM, —COOR ′ or —SO ₃ M group, M represents a hydrogen atom, monovalent metal, divalent metal, ammonium group or organic amine group, and R ′ represents an alkyl having 1 to 10 carbon atoms. In which g represents an integer of 1 to 2, for example, mercaptoethanol, thioglycerol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, thiomalic acid, Examples include octyl thioglycolate, octyl 3-mercaptopropionate, and the like from the viewpoint of chain transfer effect in a copolymerization reaction including monomers 1 to 3. Mercaptoethanol are preferable, more preferably mercaptopropionic acid. These 1 type (s) or 2 or more types can be used.

  Examples of the halogenated hydrocarbon chain transfer agent include carbon tetrachloride and carbon tetrabromide.

  Examples of other chain transfer agents include α-methylstyrene dimer, terpinolene, α-terpinene, γ-terpinene, dipentene, 2-aminopropan-1-ol and the like. A chain transfer agent can use 1 type (s) or 2 or more types.

  The chain transfer agent is preferably used as a solution, but it is more preferable to keep the temperature of the solution in the range of 10 to 50 ° C. until the polymerization is started. In particular, the chain transfer agent is allowed to coexist in a monomer solution containing monomer 2 and / or monomer 3 or a mixed solution of monomers 1 to 3, and the temperature of the solution is changed until polymerization is started. It is preferable to hold in the range of 10-50 ° C.

[Polymerization initiator]
In the production method of the present invention, it is preferable to use a polymerization initiator from the viewpoint of polymerization efficiency such as initiation of polymerization, improvement of reaction rate, shortening of polymerization time and the like. The polymerization initiator is preferably used in an amount of 5 mol% or more, more preferably 7 to 50 mol%, particularly preferably 10 to 30 mol%. The polymerization initiator is preferably introduced into the reaction system separately from the monomer solution containing monomer 2 and / or monomer 3.

  As an aqueous polymerization initiator, persulfuric acid ammonium salt or alkali metal salt or hydrogen peroxide, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis (2-methylpropionamide) Water-soluble azo compounds such as dihydrate are used. In addition, an accelerator such as sodium bisulfite and an amine compound can be used in combination with the polymerization initiator.

[solvent]
The production method of the present invention is carried out by a solvent polymerization method. Examples of the solvent used at that time include water-soluble organic solvents such as water, methyl alcohol, ethyl alcohol, isopropyl alcohol acetone, and methyl ethyl ketone. In view of handling and reaction equipment, water is preferred. In particular, when an aqueous solution is used, a monomer solution containing monomer 2 and / or monomer 3 is used for the reaction at a pH of 7 or less, further 0.1 to 6, particularly 0.2 to 4, and a copolymerization reaction is performed. It is preferable to perform it from the viewpoint of uniformity (handleability) of the monomer mixture, monomer reaction rate, and crosslinking by hydrolysis of the pyro compound of the phosphoric acid compound. In the production method of the present invention, the polymerization solvent is preferably used in a ratio of 0.1 to 5 times by weight, particularly 0.5 to 4 times by weight, based on the total weight of the monomers.

  Here, the aqueous solution is water or a solution containing 50% by weight or more of water, and may be mixed with lower alcohols such as methanol and isopropanol that can be uniformly mixed with water, and ketones such as acetone and methyl ethyl ketone. .

  In the present invention, a polymerization solvent having a dissolved oxygen concentration at 25 ° C. of 0.01 to 4.0 mg / kg, preferably 0.05 to 2.5 mg / kg is used. Here, the dissolved oxygen concentration refers to that measured at 25 ° C. by a fluorescence oximeter (FO-960: manufactured by A.S.R Co., Ltd.). In addition, when performing nitrogen substitution etc. after adding a monomer to a polymerization solvent, it is set as the dissolved oxygen concentration of the system also including a monomer. The aqueous solution is water or a solution containing 50% by weight or more of water, and may be mixed with lower alcohols such as methanol and isopropanol that can be uniformly mixed with water, and ketones such as acetone and methyl ethyl ketone. .

  The dissolved oxygen concentration of the polymerization solvent may be adjusted in a polymerization reaction tank, or a dissolved oxygen amount adjusted in advance may be used. In these cases, a sufficient amount of nitrogen is circulated with stirring. It can be performed by a method such as sufficiently repeating the substitution. From the viewpoint of operating efficiency, it is preferable to adjust the dissolved oxygen concentration by mixing nitrogen in a pipe for transferring the polymerization solvent to the polymerization tank, and it is particularly preferable to install a static mixer in the middle of the pipe. As this static mixer, commercially available ones such as New Static Mixer (manufactured by Tokyo Nisshin Jabara Co., Ltd.), Lamond Super Mixer (manufactured by Environmental Science Industrial Co., Ltd.), Noritake Static Mixer (manufactured by Noritake Limited), etc. are used. be able to.

  Until the polymerization reaction is completed, the dissolved oxygen concentration corresponding to 25 ° C. is preferably maintained at 0.01 to 4.0 mg / kg by nitrogen substitution or the like.

  In the present invention, the reaction is started using a polymerization solvent having a dissolved oxygen concentration of 0.01 to 4.0 mg / kg at 25 ° C., and in order to maintain the dissolved oxygen concentration during the reaction, It is preferable to carry out the reaction under a nitrogen atmosphere. Moreover, it is preferable to replace the atmosphere before the reaction with an inert gas. When nitrogen gas is used as the inert gas, nitrogen gas is introduced into the reaction vessel at a rate of 0.01 to 0.3 L / hr per 1 L of gas phase during the reaction, so that the dissolved oxygen concentration in the polymerization solvent is Maintained in range. Such an operation suppresses the occurrence of cross-linking (high molecular weight, gelation) even when a raw material containing a diester is used, and has excellent performance as a dispersant for a hydraulic composition of a phosphate ester polymer. This is more preferable in the production method of the present invention.

  Note that the dissolved oxygen concentration in the polymerization solvent during the reaction is almost the same as that at the start of the reaction under the introduction of the inert gas as described above, so no special detection is required. It is also possible to directly measure the dissolved oxygen concentration of the polymerization solvent during the reaction. For example, if the apparatus is equipped with an acid-resistant dissolved oxygen meter electrode, the dissolved oxygen concentration of the polymerization solvent during the reaction can be measured even in the pH range of the present invention.

  An example of the manufacturing method of this invention is shown. A predetermined amount of water is charged into the reaction vessel, and nitrogen is sufficiently circulated with stirring, and the dissolved oxygen concentration at 25 ° C. of water is 0.01-4. The temperature is raised to 0 mg / kg, and the atmosphere is replaced with an inert gas such as nitrogen. Prepare monomer 1, monomer 2, monomer 3, chain transfer agent mixed and dissolved in water, and polymerization initiator dissolved in water, and take 0.5 to 5 hours. Drip into the reaction vessel. At that time, each monomer, chain transfer agent and polymerization initiator may be dropped separately, or a mixed solution of monomers can be charged in a reaction vessel in advance and only the polymerization initiator can be dropped. is there. That is, the chain transfer agent, the polymerization initiator, and other additives may be added as an additive solution separately from the monomer solution, or may be added to the monomer solution after being added. From the viewpoint of stability, it is preferable to supply the reaction system as an additive solution separately from the monomer solution. In any case, the pH of the solution containing the monomer 2 and / or the monomer 3 is preferably 7 or less. Further, the copolymerization reaction is carried out with acid or the like while maintaining the pH at 7 or less, and preferably aging is carried out for a predetermined time. The polymerization initiator may be added dropwise at the same time as the monomer, or may be added in portions, but it is preferable to add in portions in terms of reducing unreacted monomers. For example, in the total amount of the polymerization initiator to be finally used, 1/2 to 2/3 of the polymerization initiator is added simultaneously with the monomer, and after aging for 1 to 2 hours after completion of the monomer dropping, the remainder is It is preferable to add. If necessary, it is further neutralized with an alkali agent (such as sodium hydroxide) after completion of ripening to obtain the phosphate ester polymer according to the present invention. The manufacturing method of this invention is suitable as a manufacturing method of the dispersing agent for hydraulic compositions containing the phosphate ester type polymer of the said invention.

  The phosphate ester polymer obtained by the production method of the present invention can be used as a dispersant for a hydraulic composition even in an acid form, but from the viewpoint of suppressing hydrolysis of an ester due to acidity, it is based on an alkali. Preference is given to the salt form by neutralization. Examples of the alkali include alkali metal salts or hydroxides of alkaline earth metals, ammonia, mono-, di-, and trialkanol (preferably having 2 to 6 carbon atoms) amines.

  By the production method of the present invention, the following first phosphate ester polymer and second phosphate ester polymer can be obtained.

<< first phosphate ester polymer >>
The first phosphoric acid ester-based polymer of the present invention comprises a monomer 1 and a mixed monomer containing the monomer 2 and the monomer 3 having a dissolved oxygen concentration of 0.01 to 4 at 25 ° C. It is a phosphate ester polymer obtained by copolymerization at a pH of 7 or less in a polymerization solvent of 0.0 mg / kg. Preferred structures of the monomers 1 to 3 are as described above.

  The first phosphate polymer of the present invention preferably has a weight average molecular weight (hereinafter referred to as Mw) of 10,000 to 150,000. Mw is 10,000 or more, preferably 12,000 or more, more preferably 13,000 or more, more preferably 14,000 or more, and particularly preferably 15,000 from the viewpoint of the expression of the dispersion effect and the viscosity reduction effect. From the viewpoints of high molecular weight by crosslinking, suppression of gelation and performance, from the viewpoint of dispersion effect and viscosity reduction effect, it is 150,000 or less, preferably 130,000 or less, more preferably 120,000 or less, more Preferably it is 110,000 or less, Especially preferably, it is 100,000 or less, From the both viewpoints, Preferably it is 12,000-130,000, More preferably, it is 13,000-120,000, More preferably, it is 14,000. To 110,000, particularly preferably 15,000 to 100,000.

The Mw of the first phosphate ester polymer of the present invention is measured by gel permeation chromatography (GPC) method under the following conditions.
[GPC conditions]
Column: G4000PWXL + G2500PWXL (Tosoh)
Eluent: 0.2M phosphate buffer / CH ₃ CN = 9/1
Flow rate: 1.0mL / min
Column temperature: 40 ° C
Detection: RI
Sample size: 0.2mg / mL
Reference material: Polyethylene glycol equivalent

  Further, in the chart pattern showing the molecular weight distribution obtained by the GPC method under the above conditions, the area having a molecular weight of 100,000 or more is 5% or less of the total area of the chart, so that dispersibility (required addition amount reduction) It is more preferable in terms of the viscosity reducing effect.

<< second phosphate ester polymer >>
The present invention is a phosphate ester obtained by copolymerizing the following (X) and (Y) at a pH of 7 or less in a polymerization solvent having a dissolved oxygen concentration at 25 ° C. of 0.01 to 4.0 mg / kg. A copolymer (second phosphate ester polymer) is provided. The above description can be referred to for the preferable structure of the monomer 1 and the preferable structure of the phosphate ester (Y). Also, the second phosphate ester polymer preferably has the same Mw as described above.
(X) Monomer 1 represented by the general formula (1).
(Y) Phosphate ester obtained by reacting the organic hydroxy compound represented by the general formula (4) with a phosphorylating agent.

  1-20 are preferable, as for m4 in General formula (4), 1-10 are more preferable, and 1-5 are especially preferable.

  This phosphate ester (Y) is obtained by phosphorylating the organic hydroxy compound represented by the general formula (4) with a phosphorylating agent.

  Examples of the phosphorylating agent include orthophosphoric acid, phosphorus pentoxide (anhydrous phosphoric acid), polyphosphoric acid, phosphorus oxychloride and the like, and orthophosphoric acid and phosphorus pentoxide are preferable. These may be used alone or in combination of two or more. Further, the phosphorylating agent (Z) described later is also preferable. In this invention, the quantity of the phosphorylating agent at the time of making an organic hydroxy compound and a phosphorylating agent react can be determined timely according to the target phosphate ester composition.

  Phosphoric acid ester (Y) has an organic hydroxy compound and a phosphorylating agent in a ratio defined by the following formula (I) of 2.0 to 4.0, more preferably 2.5 to 3.5, particularly 2.8. What was obtained by making it react on the conditions of -3.2 is preferable.

In the present invention, in the formula (I), the phosphorylating agent is treated as P ₂ O ₅ .n (H ₂ O) for convenience.

In particular, the phosphorylating agent includes phosphorous pentoxide (Z-1) and at least one selected from the group consisting of water, phosphoric acid and polyphosphoric acid (Z-2) [hereinafter, phosphorylating agent (Z). In this case, too, the formula (I) includes phosphorus pentoxide (Z-1) and at least one selected from the group consisting of water, phosphoric acid and polyphosphoric acid (Z-2). For the sake of convenience, the phosphorylating agent (Z) is treated as P ₂ O ₅ .n (H ₂ O).

Further, the number of moles of the phosphorylating agent defined by the formula (I) means the amount of phosphorous agent introduced into the reaction system as a raw material, particularly the amount of P ₂ O ₅ units derived from the phosphorylating agent (Z) (mole). ). The number of moles of water indicates the amount (mole) of water (H ₂ O) derived from the phosphorylating agent (Z) introduced into the reaction system as a raw material. That is, the reaction system includes water when polyphosphoric acid is represented as (P ₂ O ₅ .xH ₂ O) and orthophosphoric acid is represented as [1/2 (P ₂ O ₅ .3H ₂ O)]. It will contain all the water present in it.

  Moreover, 20-100 degreeC is preferable and, as for the temperature at the time of adding a phosphorylating agent to an organic hydroxy compound, 40-90 degreeC is more preferable. The time required for adding the phosphorylating agent to the reaction system (the time from the start of addition to the end of addition) is preferably 0.1 hour to 20 hours, and more preferably 0.5 hour to 10 hours.

  The temperature of the reaction system after adding the phosphorylating agent is preferably 20 to 100 ° C, more preferably 40 to 90 ° C. The copolymerization can be performed based on the above-described method for producing a phosphate ester polymer.

  After completion of the phosphorylation reaction, the resulting phosphoric acid condensate (an organic compound or a phosphoric acid having a pyrophosphate bond) may be reduced by hydrolysis, or even without hydrolysis, the phosphoric acid of the present invention. It is suitable as a monomer for producing an ester polymer.

<< Dispersant for hydraulic composition >>
The phosphate ester polymer of the present invention can be used as a dispersant for a hydraulic composition in various inorganic hydraulic powders that exhibit curability by a hydration reaction, including various cements. The dispersant for a hydraulic composition containing the polymer of the present invention may be powdery or liquid. In the case of a liquid form, those using water as a solvent or a dispersion medium (such as an aqueous solution) are preferable from the viewpoint of workability and reduction of environmental load. In the dispersant of the present invention, the content of the polymer of the present invention is preferably 10 to 100% by weight, more preferably 15 to 100% by weight, and still more preferably 20 to 100% by weight in the solid content. In the case of a liquid, the solid content concentration is preferably 5 to 40% by weight, more preferably 10 to 40% by weight, and still more preferably 20 to 35% by weight, from the viewpoints of manufacturability and workability. Further, the dispersant of the present invention may be used in a ratio of 0.02 to 1 part by weight and 0.04 to 0.4 part by weight in solid content concentration of the polymer with respect to 100 parts by weight of the hydraulic powder. From the viewpoint of dispersion effect.

  Examples of the cement include ordinary Portland cement, early-strength Portland cement, ultra-early-strength Portland cement, and eco-cement (for example, JIS R5214). As hydraulic powder other than cement, blast furnace slag, fly ash, silica fume and the like may be included, and non-hydraulic limestone fine powder and the like may be included. Silica fume cement or blast furnace cement mixed with cement may be used.

  The dispersant for hydraulic composition of the present invention can also contain other additives (materials). For example, resin soap, saturated or unsaturated fatty acid, sodium hydroxystearate, lauryl sulfate, alkylbenzene sulfonic acid (salt), alkane sulfonate, polyoxyalkylene alkyl (phenyl) ether, polyoxyalkylene alkyl (phenyl) ether sulfate (salt) ), Polyoxyalkylene alkyl (phenyl) ether phosphates (salts), protein materials, AE agents such as alkenyl succinic acid and α-olefin sulfonate; oxy such as gluconic acid, glucoheptonic acid, alabonic acid, malic acid, citric acid Delayers such as carboxylic acids, dextrins, monosaccharides, oligosaccharides, polysaccharides, etc .; foaming agents; thickeners; silica sand; AE water reducing agents; calcium chloride, calcium nitrite, calcium nitrate , Cal bromide Soluble calcium salts such as um, calcium iodide, chlorides such as iron chloride and magnesium chloride, sulfates, potassium hydroxide, sodium hydroxide, carbonates, thiosulfates, formic acid (salts), alkanolamines, etc. Strongening agent or accelerator; foaming agent; waterproofing agent such as resin acid (salt), fatty acid ester, oil, fat, silicone, paraffin, asphalt, wax; blast furnace slag; fluidizing agent; dimethylpolysiloxane, polyalkylene glycol fatty acid ester Anti-foaming agents such as mineral oils, oils and fats, oxyalkylenes, alcohols, amides, etc .; antifoaming agents; fly ash; melamine sulfonic acid formalin condensates, aminosulfonic acids, polymaleic acids and other polycarboxylic acids High-performance water-reducing agent such as silica; Silica fume; Rust inhibitor such as nitrite, phosphate, zinc oxide; Methyl cellulose , Celluloses such as hydroxyethyl cellulose, natural products such as β-1,3-glucan and xanthan gum, polyacrylic acid amide, polyethylene glycol, ethylene oxide adduct of oleyl alcohol or a reaction product thereof with vinylcyclohexene diepoxide, etc. Water-soluble polymers such as synthetic systems; polymer emulsions such as alkyl (meth) acrylates.

  Moreover, the dispersing agent for hydraulic compositions of the present invention is not only for ready-mixed concrete and concrete vibration products, but also for self-leveling, for refractories, for plaster, for gypsum slurry, for lightweight or heavy concrete, for AE, for repair. It is useful in any field of various concrete such as prepacked, trayy, ground improvement, grout, and cold.

<< Hydraulic composition >>
In addition, the hydraulic composition that is the target of the dispersant of the present invention has a water / hydraulic powder ratio [weight percentage (% by weight) of water and hydraulic powder in the hydraulic composition, hereinafter referred to as W / P. Is written. ] Is 65% or less, more preferably 10 to 60%, still more 12 to 57%, and particularly 15 to 55% and further 20 to 55% in that the low-viscosity effect is exhibited.

  Moreover, although the hydraulic composition of this invention is a paste, mortar, concrete, etc. containing water and hydraulic powder (cement), you may contain an aggregate. Examples of the aggregate include fine aggregate and coarse aggregate. The fine aggregate is preferably mountain sand, land sand, river sand and crushed sand, and the coarse aggregate is preferably mountain gravel, land gravel, river gravel and crushed stone. Depending on the application, lightweight aggregates may be used. The term “aggregate” is based on “Concrete Overview” (published on June 10, 1998, published by Technical Shoin).

  The monomer composition of Table 1 and the following synthesis examples were combined as shown in Table 3 to produce phosphate ester polymers. About one combination, it superposed | polymerized 3 times, respectively, and the dispersion | variation in the performance as a dispersing agent for hydraulic compositions of a phosphate ester polymer was evaluated.

(1) Production method (1-1) Composition No. Synthesis Examples A1 to A4 by A
Synthesis example A1
A glass reaction vessel (four-necked flask) equipped with a stirrer was charged with 197 g of water, and reduced pressure and nitrogen substitution were repeated while stirring, so that the dissolved oxygen concentration of water was 0.2 mg / kg at 25 ° C. Next, the temperature was raised to 80 ° C. in a nitrogen atmosphere while introducing 3 ml / min of nitrogen per 1000 parts by weight of the total charge. 38 g of ω-methoxypolyethylene glycol monomethacrylate (addition mole number of ethylene oxide 9: NK ester M90G manufactured by Shin-Nakamura Chemical Co., Ltd.), mono (2-hydroxyethyl) methacrylate ester and di [(2-hydroxyethyl) methacrylate phosphate Acid] ester mixture (Fosmer M: Unichemical Co., Ltd.) 41.6 g and 3-mercaptopropionic acid 6.0 g in water 38 g and ammonium persulfate. Two of 5.1 g dissolved in 59 g of water were added dropwise over 1.5 hours. After aging for 1 hour, 2.6 g of ammonium persulfate dissolved in 30 g of water was added dropwise over 30 minutes, and then aging was performed at the same temperature (80 ° C.) for 1.5 hours. After completion of aging, the mixture was neutralized with 51.7 g of a 20% aqueous sodium hydroxide solution to obtain a phosphate ester polymer (pH during monomer polymerization was 1.2).

Synthesis example A2
A phosphate ester polymer was obtained in the same manner as in Synthesis Example A1 except that the dissolved oxygen concentration of water was 2.1 mg / kg (pH during monomer polymerization was 1.2).

Synthesis example A3
A phosphate ester polymer was obtained in the same manner as in Synthesis Example A1 except that the dissolved oxygen concentration of water was 3.8 mg / kg (pH during monomer polymerization was 1.2).

Synthesis example A4
A phosphate ester polymer was obtained in the same manner as in Synthesis Example A1 except that the dissolved oxygen concentration of water was 4.5 mg / kg (pH during monomer polymerization was 1.2).

(1-2) Composition No. Synthesis examples B1-B2 by B
Synthesis example B1
A glass reaction vessel (four-necked flask) equipped with a stirrer was charged with 366 g of water, and reduced pressure and nitrogen substitution were repeated while stirring, so that the dissolved oxygen concentration of water was 0.2 mg / kg at 25 ° C. Next, the temperature was raised to 80 ° C. in a nitrogen atmosphere while introducing 3 ml / min of nitrogen per 1000 parts by weight of the total charge. 450 g of ω-methoxypolyethylene glycol monomethacrylate (average number of added moles of ethylene oxide 23) (effective content 60.8%, moisture 35%), mono (2-hydroxyethyl) methacrylate phosphate and di [(2 -Hydroxyethyl) Methacrylic acid] ester mixture (A) 71.6 g and 3-mercaptopropionic acid 4.5 g mixed with ammonium persulfate. Two of 8.4 g dissolved in 48 g of water were added dropwise over 1.5 hours. After aging for 1 hour, 1.8 g of ammonium persulfate dissolved in 10 g of water was added dropwise over 30 minutes, and then aging was carried out at the same temperature (80 ° C.) for 1.5 hours. After completion of aging, the mixture was neutralized with 44.4 g of a 32% aqueous sodium hydroxide solution to obtain a phosphate ester polymer (pH during monomer polymerization was 1.0).

The phosphoric acid ester (A) used here was charged with 200 g of 2-hydroxyethyl methacrylate and 85% phosphoric acid (H ₃ PO ₄ ) 36.0 in a reaction vessel, and phosphorous pentoxide (anhydrous phosphoric acid) (P ₂ O ₅ ) 89.1 g was gradually added while cooling so that the temperature did not exceed 60 ° C., the reaction temperature was set to 80 ° C., the mixture was reacted for 6 hours and cooled.

Synthesis example B2
A phosphate ester polymer was obtained in the same manner as in Synthesis Example B1 except that the dissolved oxygen concentration of water was 4.5 mg / kg (pH during monomer polymerization was 1.0).

(1-3) Composition No. Synthesis examples C1 to C2 by C
Synthesis example C1
A glass reaction vessel (four-necked flask) equipped with a stirrer was charged with 218 g of water, and reduced pressure and nitrogen substitution were repeated while stirring, so that the dissolved oxygen concentration of water was 0.2 mg / kg at 25 ° C. Next, the temperature was raised to 80 ° C. in a nitrogen atmosphere while introducing 3 ml / min of nitrogen per 1000 parts by weight of the total charge. ω-methoxypolyethyleneglycol monomethacrylate (addition mole number of ethylene oxide 23: NK ester M230G manufactured by Shin-Nakamura Chemical Co., Ltd., mono 2-hydroxyethyl phosphate) methacrylate ester and di [(2-hydroxyethyl) methacrylic acid phosphate ] A mixture of ester (Phosmer M: Unichemical Co., Ltd.) 32.3 g and 3-mercaptopropionic acid 1.1 g in water 55 g and ammonium persulfate. Two of 3.8 g dissolved in 43 g of water were added dropwise over 1.5 hours. After aging for 1 hour, 1.9 g of ammonium persulfate dissolved in 22 g of water was added dropwise over 30 minutes, and then aging was performed at the same temperature (80 ° C.) for 1.5 hours. After completion of the aging, the mixture was neutralized with 40.1 g of a 20% aqueous sodium hydroxide solution to obtain a phosphate ester polymer (pH during monomer polymerization was 1.3).

Synthesis example C2
A phosphoric ester polymer was obtained in the same manner as in Synthesis Example C1 except that the dissolved oxygen concentration of water was 4.5 mg / kg (pH during monomer polymerization was 1.3).

(2) Monomer composition Table 1 shows the charged raw materials and charged ratios of monomers 1 to 3.

The symbols in the table are as follows.
MEPEG-E: ω-methoxypolyethylene glycol monomethacrylate HEMA-MPE: phosphoric acid mono-[(2-hydroxyethyl) methacrylic acid] ester HEMA-DPE: phosphoric acid di-[(2-hydroxyethyl) methacrylic acid ] Ester / Mw: Weight average molecular weight of phosphate ester polymer

(3) Evaluation method The mortar of the mixing | blending of Table 2 was tested using the phosphate ester type polymer obtained by the said manufacturing method. The results are shown in Table 3. Evaluation was performed by the following methods for dispersibility and viscosity.
(3-1) Mixing mortar

The materials used in Table 2 are as follows.
C: Ordinary cement (a 1: 1 mixture of ordinary Portland cement manufactured by Taiheiyo Cement Co., Ltd. and ordinary Portland cement manufactured by Sumitomo Osaka Cement Co., Ltd.)
W: Ion exchange water S: Mountain sand from Kimitsu, Chiba Prefecture

(3-2) Preparation of mortar In a container (1 L stainless beaker: inner diameter 120 mm), about 1/2 amount of S shown in Table 2 was added, then C was added, and the remaining S was further added and stirred. Dispersant and water mixed in advance after 25 seconds of air kneading at 200 rpm using a Z-2310 manufactured by EYELA (Tokyo Rika Kikai Co., Ltd., stirring rod: height 50 mm, inner diameter 5 mm × 6 pieces / length 110 mm) The mixed solution was added over 5 seconds, and the material between the wall surface and the stirring bar was scraped off for 30 seconds after the addition, and kneaded at 200 rpm for 3 minutes after the water was added to prepare a mortar. In addition, an antifoamer was added as needed, and it adjusted so that entrained air amount might be 2% or less.

(3-3) Evaluation (3-3-1) Dispersibility Phosphate ester necessary for a mortar flow value of 200 mm using a cone having an upper opening diameter of 70 mm, a lower opening diameter of 100 mm, and a height of 60 mm The dispersibility immediately after kneading was evaluated by the addition amount of the polymer (based on the effective weight% of cement, expressed in% in the table). In addition, 200 mm of this mortar flow value is an average value of the maximum value of the mortar flow value and the mortar flow value measured in the direction perpendicular to the length of ½ of the line segment that gives the maximum value. The smaller the amount added, the stronger the dispersibility.

(3-3-2) Viscosity A recorder was connected to the torque tester shown in FIG. 1, and the torque of the mortar immediately after kneading was measured. The viscosity was calculated from the torque of the mortar based on the torque-viscosity relational expression created in advance with polyethylene glycol (Mw20,000) shown in FIG. At the time of creating the torque-viscosity relational expression of polyethylene glycol, the torque output voltage value (mV) is recorded from the recorder by the monitor output 60W and the output signal DC0-5V.

  The polymerization reaction in Table 3 was carried out by changing the day without continuously performing the first to third times, and different raw materials were used for each monomer lot. In Examples 1 to 5, the molecular weight variation was small, and the performance (resulting addition amount, mortar viscosity) obtained as a result was the same with good reproducibility.

Schematic diagram of torque tester and recorder used for viscosity measurement in Examples and Comparative Examples Torque-viscosity relational expression with polyethylene glycol (Mw 20,000) used for viscosity calculation in Examples and Comparative Examples

Claims (11)

A monomer 1 represented by the following general formula (1), a monomer 2 represented by the following general formula (2), and a monomer 3 represented by the following general formula (3): 25 A method for producing a phosphate ester polymer, which is copolymerized at a pH of 7 or less in a polymerization solvent having a dissolved oxygen concentration at 0.01 ° C. of 0.01 to 4.0 mg / kg.

[Wherein R ¹ and R ² are each a hydrogen atom or a methyl group, R ³ is a hydrogen atom or —COO (AO) _n X, AO is an oxyalkylene group or oxystyrene group having 2 to 4 carbon atoms, n is It is the average added mole number of AO, the number of 3-200, X represents a hydrogen atom or a C1-C18 alkyl group. ]

[Wherein, R ⁴ represents a hydrogen atom or a methyl group, R ⁵ represents an alkylene group having 2 to 12 carbon atoms, m1 represents a number of 1 to 30, and M represents a hydrogen atom, an alkali metal or an alkaline earth metal. ]

[Wherein R ⁶ and R ⁸ are each a hydrogen atom or a methyl group, R ⁷ and R ⁹ are each an alkylene group having 2 to 12 carbon atoms, m2 and m3 are each a number from 1 to 30 and M is hydrogen. Represents an atom, an alkali metal or an alkaline earth metal. ] The production method according to claim 1, wherein the polymerization solvent is one in which the dissolved oxygen concentration is adjusted by mixing the polymerization solvent and nitrogen gas using a static mixer.   The method for producing a phosphate ester polymer according to claim 1 or 2, wherein the monomers 1 to 3 are copolymerized in the presence of a chain transfer agent.   The manufacturing method of the phosphate ester type | system | group polymer of Claim 3 which uses the said chain transfer agent 4 mol% or more with respect to the total mole number of the monomers 1-3.   The said monomers 1-3 are copolymerized in presence of a 5 mol% or more polymerization initiator with respect to the total mole number of the said monomers 1-3, The any one of Claims 1-4. A method for producing a phosphate ester polymer.   The production according to any one of claims 1 to 5, wherein the content of unreacted monomers 1 to 3 in the reaction product is 5 mol% or less based on the total amount of monomers 1 to 3 charged. Method. A monomer 1 represented by the following general formula (1), a monomer 2 represented by the following general formula (2), and a monomer 3 represented by the following general formula (3): 25 The manufacturing method of the dispersing agent for hydraulic compositions which copolymerizes at pH 7 or less in the polymerization solvent whose dissolved oxygen concentration in 0.01 degreeC-4.0 mg / kg.

[Wherein R ¹ and R ² are each a hydrogen atom or a methyl group, R ³ is a hydrogen atom or —COO (AO) _n X, AO is an oxyalkylene group or oxystyrene group having 2 to 4 carbon atoms, n is It is the average added mole number of AO, the number of 3-200, X represents a hydrogen atom or a C1-C18 alkyl group. ]

[Wherein, R ⁴ represents a hydrogen atom or a methyl group, R ⁵ represents an alkylene group having 2 to 12 carbon atoms, m1 represents a number of 1 to 30, and M represents a hydrogen atom, an alkali metal or an alkaline earth metal. ]

[Wherein R ⁶ and R ⁸ are each a hydrogen atom or a methyl group, R ⁷ and R ⁹ are each an alkylene group having 2 to 12 carbon atoms, m2 and m3 are each a number from 1 to 30 and M is hydrogen. Represents an atom, an alkali metal or an alkaline earth metal. ] Monomer 1 containing monomer 1 represented by the following general formula (1), monomer 2 represented by the following general formula (2) and monomer 3 represented by the following general formula (3) A phosphoric ester polymer obtained by copolymerizing the body at a pH of 7 or less in a polymerization solvent having a dissolved oxygen concentration at 25 ° C. of 0.01 to 4.0 mg / kg.

[Wherein R ¹ and R ² are each a hydrogen atom or a methyl group, R ³ is a hydrogen atom or —COO (AO) _n X, AO is an oxyalkylene group or oxystyrene group having 2 to 4 carbon atoms, n is It is the average added mole number of AO, the number of 3-200, X represents a hydrogen atom or a C1-C18 alkyl group. ]

[Wherein, R ⁴ represents a hydrogen atom or a methyl group, R ⁵ represents an alkylene group having 2 to 12 carbon atoms, m1 represents a number of 1 to 30, and M represents a hydrogen atom, an alkali metal or an alkaline earth metal. ]

[Wherein R ⁶ and R ⁸ are each a hydrogen atom or a methyl group, R ⁷ and R ⁹ are each an alkylene group having 2 to 12 carbon atoms, m2 and m3 are each a number from 1 to 30 and M is hydrogen. Represents an atom, an alkali metal or an alkaline earth metal. ] Phosphate ester copolymer obtained by copolymerizing the following (X) and (Y) at a pH of 7 or less in a polymerization solvent having a dissolved oxygen concentration at 25 ° C. of 0.01 to 4.0 mg / kg: .
(X) Monomer 1 represented by the following general formula (1).
(Y) Phosphate ester obtained by reacting an organic hydroxy compound represented by the following general formula (4) with a phosphorylating agent.

[Wherein R ¹ and R ² are each a hydrogen atom or a methyl group, R ³ is a hydrogen atom or —COO (AO) _n X, AO is an oxyalkylene group or oxystyrene group having 2 to 4 carbon atoms, n is It is the average added mole number of AO, the number of 3-200, X represents a hydrogen atom or a C1-C18 alkyl group. ]

[Wherein, R ¹⁰ represents a hydrogen atom or a methyl group, R ¹¹ represents an alkylene group having 2 to 12 carbon atoms, and m4 represents a number of 1 to 30. ]   The dispersing agent for hydraulic compositions containing the phosphate ester polymer of Claim 8 or 9.   A hydraulic composition comprising hydraulic powder, water, and the dispersant for hydraulic composition according to claim 10.

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