JP4884779B2 - Method for producing phosphate ester polymer - Google Patents

Description

  The present invention relates to a method for producing a phosphate ester polymer. 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 mold form 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.

Against this background, Patent Document 1 discloses a concrete admixture containing a vinyl copolymer containing a high-chain-length oxyalkylene group and a specific monomer as essential components. Further, Patent Document 2 discloses a monoester or monoether having a polyalkylene glycol chain in order to obtain a cement dispersant capable of exhibiting excellent flow characteristics, high dispersion effect and quick setting regardless of the mixing ratio of water. And a polymer of a monomer having an unsaturated bond and a phosphate group. Patent Document 3 discloses a dispersant for a hydraulic composition having a low mortar viscosity, which contains a copolymer having a monomer unit containing an alkylene glycol ether and a maleic acid monomer unit.
JP 11-79811 A JP 2000-327386 A JP 2004-168635 A

  However, the polymer of Patent Document 1 has a limit in viscosity reduction, and the polymer production method described in Patent Document 2 obtains a polymer having a target molecular weight by using a specific monomer. However, in order to further improve the fluidity and viscosity reduction, a production method with a higher degree of freedom in the structure of the obtained polymer is desired.

  An object of the present invention is to provide an excellent dispersion effect or viscosity reduction effect to a hydraulic composition containing a hydraulic powder, and further to provide both excellent effects, and the dispersion for a hydraulic composition having good performance. Another object of the present invention is to provide a method capable of producing a phosphoric ester polymer that can be used as an agent at an industrially practical level.

  The present invention includes 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”) at a pH of 7 or less. Also referred to as a manufacturing method).

[Wherein R ¹ and R ² are each a hydrogen atom or a methyl group, R ³ is a hydrogen atom or —CH ₂ O (AO) _n X, AO is an oxyalkylene group or oxystyrene group having 2 to 4 carbon atoms, n is the average addition 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 method for producing a phosphate ester copolymer (second phosphorus) obtained by reacting the following (X) and (Y) with a phosphorylating agent (Z). Also referred to as a method for producing an acid ester polymer).
(X) Monomer 1 represented by the following general formula (1)
(Y) Organic hydroxy compound represented by the following general formula (4)

[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. ]

  Moreover, this invention relates to the dispersing agent for hydraulic compositions containing the phosphate ester type polymer obtained by the manufacturing method of the said invention, and the said polymer. 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. A method for producing a polymer is provided. Moreover, the production method of the present invention does not impair the properties 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.

  Even if the phosphate ester polymer of the present invention is a highly durable high-strength hydraulic composition having a low water content and a large amount of hydraulic powder, it has a fluidity equal to or higher than that of a conventional polycarboxylic acid-based water reducing agent. / Or develops low viscosity. As a result, it is possible to impart workability and workability such as excellent pumping, driving and filling into a mold.

<< Production Method of First Phosphate Ester Polymer >>
The present invention relates to a method for producing a phosphate ester polymer in which monomer 1, monomer 2, and monomer 3 are copolymerized at a pH of 7 or less. 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 monomer 2 which is a phosphate ester monomer, and the monomer 3 are copolymerized at a pH of 7 or less. 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, and further preferably 90 mol% or more, and particularly preferably all AO are EO groups. 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.

  As the monomer 1, etherified product of one-end alkyl-blocked polyalkylene glycol such as methoxypolyethylene glycol, methoxypolypropylene glycol, methoxypolybutylene glycol, methoxypolystyrene glycol, ethoxypolyethylenepolypropyleneglycol and (meth) allyl alcohol, and ( An alkylene oxide adduct adduct having 2 to 4 carbon atoms to (meth) allyl alcohol is preferably used. Specific examples include polyoxyethylene allyl ether and methoxypolyethylene glycol allyl ether. Here, n in the formula (1) is 3 to 200, preferably 4 to 120, from the viewpoint of the dispersibility of the polymer in the hydraulic composition and the effect of imparting viscosity. 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, from the viewpoint of reactivity (polymerization) with monomer 1, phosphoric acid mono-[(2-hydroxyethyl) acrylic acid] ester is preferable.

[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, from the viewpoint of reactivity (polymerization) with the monomer 1, di-[(2-hydroxyethyl) acrylic acid] ester is preferable.

  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 (Daihachi Chemical), Kayamar (Nippon Kayaku), Ethyleneglycol methacrylate Available as phosphate (Aldrich reagent).

Moreover, the mixed monomer containing the monomer 2 and the monomer 3 is, for example, an organic hydroxy compound represented by the general formula (4), phosphoric anhydride (P ₂ O ₅ ), and water in a predetermined charging ratio. Can be produced as a reaction product.

[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. ]

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

  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 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 described below [hereinafter referred to as phosphorylating agent (Z ′)] 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.

  In the phosphate ester, the ratio of the organic hydroxy compound and the phosphorylating agent defined by the following formula (I) is 2.0 to 4.0, more preferably 2.5 to 3.5, and particularly 2.8 to 3. What was obtained by making it react on condition of 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 is preferably phosphorous pentoxide (Z-1) and phosphorylating agent (Z) containing at least one (Z-2) selected from the group consisting of water, phosphoric acid and polyphosphoric acid. In the formula (I), a phosphorylating agent (Z ′) containing phosphorus pentoxide (Z-1) and at least one (Z-2) selected from the group consisting of water, phosphoric acid and polyphosphoric acid is used. For convenience, it will be treated as P ₂ O ₅ · n (H ₂ O).

The number of moles of the phosphorylating agent defined by the formula (I) is the amount of P ₂ O ₅ unit derived from the phosphorylating agent introduced into the reaction system as a raw material, particularly the phosphorylating agent (Z ′) ( Mol). 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.

  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.

  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 charged 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, 20/80-80/20 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 (total Is 100). 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, by reacting at a pH of 7 or less, gelation is suppressed, and a phosphate ester polymer suitable as a dispersant for a hydraulic composition is stably and industrially practical with good reproducibility. Can be manufactured at a certain 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 such a viewpoint, in the present invention, it is preferable to use a chain transfer agent of 1 mol% or more, further 3 mol% or more with respect to the total number of moles of monomers 1 to 3 in the copolymerization. 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 3 to 3 in relation to the monomers 1 to 3. It is preferable to use 100 mol%,
(1-2) When the molar ratio of the monomer 2 to the monomer 3 in the monomers 1 to 3 is less than 50 mol%, the chain transfer agent is 1 to 1 with respect to the monomers 1 to 3. 60 mol% is preferably used,
(2) When n of monomer 1 exceeds 30, the chain transfer agent is preferably used in an amount of 3 to 50 mol% with respect to 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 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 mounted on the coalescence, it is more than 95 mol% to 100 mol%, and more preferably 97 to 100 mol%.

  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 present invention, a chelating agent is preferably used, and a phosphonic acid chelating agent is preferable from the viewpoint of high chelating ability even in a small amount and capable of capturing a transition metal ion in the polymerization reaction system.

  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. Is copolymerized at a pH of 7 or less. 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 from the viewpoint of uniformity of the monomer solution, prevention of gelation, and suppression of performance degradation. In the present invention, 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 defined as the pH during the reaction. 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 is preferably 7 or less) is dropped into the reaction system.
(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 the monomer 3 (pH is arbitrary but is preferably 7 or less) are separately added dropwise to the reaction system.
(Iv) Reaction is carried out in a polymerization solvent by appropriately combining the above. 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 preferable 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 is preferably used in an amount of 1 mol% or more, and more preferably 3 mol% or more based on the total number of moles of monomers 1 to 3 from the viewpoint of suppressing gelation and adjusting the suitable molecular weight.

  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.

[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 3 mol% or more, more preferably 5 to 50 mol%, particularly preferably 7 to 30 mol%.

  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 first production method of the present invention can be carried out by a solution 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.

  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 this invention, it is preferable to have the process of post-processing a copolymerization reaction material with hydrogen peroxide. As described above, in particular, when a chain transfer agent such as a water-soluble thiol compound is used, it is preferable for inactivating the compound. The amount of hydrogen peroxide used is preferably 50 to 3000 mg / kg, more preferably 100 to 1800 mg / kg, based on the copolymerization reaction product (approximate to the polymerization reaction system).

  An example of the 1st manufacturing method of this invention is shown. A predetermined amount of water is charged into a reaction vessel, the atmosphere is replaced with an inert gas such as nitrogen, and the temperature is raised. 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, after completion of ripening, the solution is further neutralized with an alkali agent (sodium hydroxide or the like), and after-treatment with hydrogen peroxide is performed 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 said phosphate ester type polymer.

<< Method for Producing Second Phosphate Ester Polymer >>
From the viewpoint of fluidity and low viscosity, which are functions of a dispersant for hydraulic composition, a polymer composed of monomer 1 and monomer 2 is preferable, but industrially, usually a single amount. It is currently available as a mixture containing the body 2 and the monomer 3. According to the first production method of the present invention, a phosphate ester polymer suitable as a dispersant can be obtained from such a mixture.

On the other hand, according to the second production method of the present invention, it is possible to provide a copolymer mainly composed of monomer 1 and monomer 2 and having a very small ratio of monomer 3. Specifically, after the following (X) and (Y) are copolymerized, the phosphoric acid ester copolymer can be obtained by reacting with the phosphorylating agent (Z). In the second production method, since there is no bifunctional monomer that leads to a high molecular weight of the polymer during copolymerization, it is easy to control the molecular weight of the resulting copolymer. Moreover, since phosphoric acid diesters are not easily formed by phosphorylation of the obtained copolymer, a phosphoric acid ester polymer having a small composition ratio of structural units corresponding to the structure derived from the monomer 3 is obtained as a result.
(X) Monomer 1 represented by the following general formula (1)
(Y) Organic hydroxy compound represented by the following general formula (4) (hereinafter referred to as monomer 4)

[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 copolymerization of (X) and (Y) is preferably carried out at a pH of 7 or less.

  The phosphorylating agent (Z) is not particularly specified as long as it can phosphorylate a hydroxyl group, but includes orthophosphoric acid, phosphorous pentoxide (anhydrous phosphoric acid), polyphosphoric acid, phosphorous oxychloride and the like.

  In the copolymerization of the monomers, the charged molar ratio of the monomer 1 and the monomer 4 is as follows: monomer 1 / monomer 4 = 5/95 to 95/5, and further 10/90 to 90/10 is preferred.

  Hereinafter, more preferable production conditions in the second production method will be described from the viewpoint of adjusting the suitable molecular weight and designing the performance of the dispersant for hydraulic composition.

  In the second production method, the polymerization initiator is preferably 15 mol% or more, more preferably 50 to 100 mol%, based on the total number of moles of the monomer 1 and the monomer 4. When the amount of the polymerization initiator is 15 mol% or more based on the total number of moles of the monomer 1 and the monomer 4, the unreacted monomer 1 and the monomer 4 are reduced, and the dispersion for the hydraulic composition is performed. The performance as an agent is improved.

  As a polymerization initiator, persulfuric acid ammonium salt or alkali metal salt or hydrogen peroxide, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis (2-methylpropionamide) dihydrate, etc. Is mentioned.

  In addition, an accelerator such as sodium bisulfite and an amine compound can be used in combination with the polymerization initiator. A chain transfer agent can also be added depending on the purpose such as molecular weight control. Examples of chain transfer agents include thiol chain transfer agents and halogenated hydrocarbon chain transfer agents.

  In addition, as the polymerization apparatus and the solvent, those described in the production of the first phosphate polymer can be used.

  In the second production method of the present invention, the polymerization temperature of the monomer 1 and the monomer 4 is preferably 60 ° C. or higher, and more preferably 80 to 120 ° C.

  In the phosphorylation of the obtained copolymer, there is no particular designation as long as the hydroxyl group in the polymer can be phosphorylated, but orthophosphoric acid, phosphorous pentoxide (anhydrous phosphoric acid), polyphosphoric acid, phosphorous oxychloride, etc. Among them, polyphosphoric acid is preferable. These may be used alone or in combination of two or more. Further, the phosphorylating agent (Z ′) shown in the first production method is also preferable.

  The amount of the phosphorylating agent (Z) can be appropriately determined according to the intended copolymer composition, and is preferably 1.0 equivalent or more based on the hydroxyl group of the charged monomer (monomer 4). More preferably, it is 2.0 equivalents or more, and still more preferably 4.0 equivalents or more. When the amount of the phosphorylating agent is 1.0 equivalent or more, the phosphorylation rate of the hydroxyl group in the copolymer is improved, and the performance as a dispersant for a hydraulic composition is improved.

  In the production of the first or second phosphate ester polymer of the present invention, in addition to the above monomers 1 to 3 or monomers 1 and 4, other monomers that can be copolymerized are used. You can also. Examples of other copolymerizable monomers include allyl sulfonic acid, methallyl sulfonic acid, any of these alkali metal salts, alkaline earth metal salts, ammonium salts, and amine salts. 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 and 2 in all monomers is preferably 30 to 100 mol%, more preferably 50 to 100 mol%, and particularly preferably 75 to 100 mol%. Further, as a dispersant for a hydraulic composition From the viewpoint of achieving the above performance, it is more than 95 mol% to 100 mol%, more preferably 97 to 100 mol%, particularly 100 mol%.

  By the manufacturing method of the 1st or 2nd phosphate ester polymer of this invention, the structural unit derived from General formula (1), the structural unit derived from General formula (2), and General formula (3) A phosphate ester polymer containing the derived structural unit is obtained.

  The phosphate ester 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. It is preferable to have Mw in this range, and the ratio Mw / Mn of Mw to number average molecular weight (Mn) is 1.0 to 2.6. Here, the value of Mw / Mn is the degree of dispersion. The closer the value is to 1, the closer the molecular weight distribution is to the monodispersion, and the farther from 1 (the larger) the wider the molecular weight distribution.

  The phosphate ester polymer of the present invention having the Mw / Mn value as described above is a polymer having a branched structure based on a diester structure, but has a great feature that the molecular weight distribution is very narrow. Such a phosphoric ester polymer of the present invention can be suitably produced by the production method of the present invention described later.

  Mw / Mn of the phosphoric ester polymer of the present invention as described above is 1.0 or more from the viewpoint of ensuring practical production ease, dispersibility, viscosity reduction effect, and versatility with respect to materials and temperature. From the viewpoint of achieving both dispersibility and viscosity reduction effect, it is preferably 2.6 or less, more preferably 2.4 or less, more preferably 2.2 or less, still more preferably 2.0 or less, and particularly preferably 1 From the viewpoint of combining the above two points, it is preferably 1.0 to 2.4, more preferably 1.0 to 2.2, more preferably 1.0 to 2.0, and particularly preferably. 1.0 to 1.8.

Mw and Mn of the phosphate ester polymer of the present invention are those measured by gel permeation chromatography (GPC) method under the following conditions. In addition, Mw / Mn of the phosphate ester type polymer in the present invention is calculated based on the peak of the polymer.
[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

  The phosphate ester polymer satisfying Mw / Mn as described above has an appropriate branched structure by suppressing cross-linking by the monomer 3 which is a diester, and has a structure in which adsorbing groups are closely present in the molecule. It is thought to form. Further, since the degree of dispersion Mw / Mn is controlled within a predetermined range, it approaches a system in which molecules of the same size are monodispersed, so that it is considered possible to increase the amount of adsorption on the adsorption target substance (for example, cement particles). Satisfying both of these conditions makes it possible to densely pack the substance to be adsorbed, such as cement particles, and is estimated to be effective in achieving both a dispersibility and a viscosity reducing effect.

  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.

<< 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 >>
The hydraulic composition of this invention contains the said dispersing agent for hydraulic compositions, hydraulic powder, and water. The hydraulic composition of the present invention has an unprecedented low viscosity, and is excellent in workability such as pumping, driving and filling into a mold, and workability.

  The hydraulic composition 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]. Indicated as / P. ] Is 65% or less, more preferably 10 to 60%, still more preferably 12 to 57%, particularly preferably 15 to 55%, and further preferably 20 to 55%.

  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 hydraulic composition of the present invention can be used for buildings such as buildings, secondary concrete products, civil engineering applications and the like.

<Examples 1-1 to 1-3 and Comparative Example 1-1>
70.9 g of water was charged into a glass reaction vessel (four-necked flask) equipped with a stirrer, purged with nitrogen while stirring, and heated to 80 ° C. in a nitrogen atmosphere. 130 g of methoxypolyethylene glycol allyl ether (average added mole number of ethylene oxide 32.5: AG-325M manufactured by Nippon Emulsifier Co., Ltd.) and mono-[(2-hydroxyethyl) acrylic acid] ester (hereinafter, hydroxyethyl acrylate) 43.4 g and 3 of a mixture (Ethyleneglycol acrylate phosphate: light acrylate P1A) of phosphoric acid di-[(2-hydroxyethyl) acrylic acid] ester (hereinafter also referred to as hydroxyethyl acrylate diphosphate ester) -A monomer solution prepared by adding a predetermined amount of 20% aqueous sodium hydroxide to a solution obtained by mixing and dissolving 0.26 g (or 0.79 g) of mercaptopropionic acid in 130 g of water, and adjusting the pH (Table 1); 2.82g sodium disulfate into 45g water To that solution, the two parties which were mixed and dissolved 2.40g of 35% hydrogen peroxide were each added dropwise for 2.0 hours. After aging for 1 hour, a solution prepared by dissolving 1.41 g of sodium peroxodisulfate in 15 g of water and a solution prepared by mixing and dissolving 1.20 g of 35% hydrogen peroxide over 30 minutes were added dropwise over a period of 1.5 hours. Aging at temperature (80 ° C.). After completion of aging, the copolymer was neutralized with 20% sodium hydroxide solution.

<Comparative Example 1-2>
70.9 g of water was charged into a glass reaction vessel (four-necked flask) equipped with a stirrer, purged with nitrogen while stirring, and heated to 80 ° C. in a nitrogen atmosphere. 130 g of methoxypolyethylene glycol allyl ether (average added mole number of ethylene oxide: 32.5: AG-325M manufactured by Nippon Emulsifier Co., Ltd.), mono-[(2-hydroxyethyl) acrylic acid] ester and di- [ (2-hydroxyethyl) a mixture of acrylic acid] ester (Ethyleneglycol acrylate phosphate: light acrylate P1A) and 43.4g adding a predetermined amount of a 20% sodium hydroxide aqueous solution of a mixture dissolved in water 130 g, adjusting the pH (Table 1) The monomer solution, 2.82 g of sodium peroxodisulfate dissolved in 45 g of water, and the mixture of 2.40 g of 35% hydrogen peroxide mixed and dissolved for 2 hours each. It was dripped. During the addition, the reaction product gelled.

  Table 1 summarizes the above examples and comparative examples. In Table 1, Mw is the weight average molecular weight, EO is ethylene oxide, and the number is the average number of moles added (the same applies hereinafter). Moreover, the chain transfer agent and polymerization initiator of the raw material used were used in the molar ratios in the table with respect to a total of 100 moles of monomer components such as monomers 1 to 3 (the same applies hereinafter).

<Test Example 1>
Using the copolymers of Table 1 obtained in Examples 1-1 to 1-3 and Comparative Examples 1-1 to 1-2, a test was conducted on the mortar having the composition shown in Table 2. The results are shown in Table 3. Evaluation was performed by the following methods for dispersibility and viscosity.
(1) Mortar combination

The materials used in Table 2 are as follows.
C: Ordinary cement (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
W / C: percentage by weight (% by weight) of water (W) and cement (C) (the same applies hereinafter)

(2) Preparation of mortar Into a container (1 L stainless beaker: inner diameter 120 mm), about 1/2 amount of S of the composition shown in Table 2 is added, then C is added, and the remaining S is further added as a stirrer. Mixing of dispersant and water mixed in advance after 25 seconds of air kneading at 200 rpm using EYELA Z-2310 (Tokyo Rika Instruments, stirring rod: height 50 mm, inner diameter 5 mm × 6 pieces / length 110 mm) The solution was added over 5 seconds, the material between the wall and the stirring bar was scraped off for 30 seconds after the addition, and water was added and kneaded for 3 minutes 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) Evaluation (3-1) Dispersibility Use of a cone having an upper opening diameter of 70 mm, a lower opening diameter of 100 mm, and a height of 60 mm, and an addition amount of a copolymer necessary for a mortar flow value to be 200 mm ( Dispersibility was evaluated based on the effective weight% of cement (% 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.

(3-2) Viscosity A recorder is connected to the torque tester shown in FIG. 1, and the torque of the mortar is 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.

  From the results in Table 3, the phosphate ester polymers of Examples 1-1 to 1-3 were copolymerized with the monomer solution containing monomer 2 and / or monomer 3 having a pH of 7 or less. Then, it can be seen that the dispersibility is stronger. On the other hand, when the solution containing the monomers 2 and 3 is copolymerized at a pH of 7 or more, even if it is gelled or a copolymer is obtained, the dispersibility is weak. In the copolymer of the example, the mortar viscosity is also lower than that of the comparative example, and it becomes a dispersant with good vanlas.

<Examples 2-1 to 2-15, Comparative Example 2-1>
(1) Manufacture of phosphoric acid ester product In a reaction vessel, cool 2 g of 2-hydroxyethyl acrylate to 83.2 g of phosphorous pentoxide (anhydrous phosphoric acid) (P ₂ O ₅ ) so that the temperature does not exceed 60 ° C. While adding gradually. After completion, the reaction temperature was set to 80 ° C., the reaction was performed for 6 hours, and after cooling, phosphoric acid mono-[(2-hydroxyethyl) acrylic acid] ester and phosphoric acid di-[(2-hydroxyethyl) acrylic acid] A phosphate esterified product, which is a mixture containing an ester, was obtained. The total concentration of mono- and di-forms of the resulting phosphoric acid ester was about 75%. In addition, the preparation ratio of 2-hydroxyethyl acrylate and phosphoric anhydride (P ₂ O ₅ ) was changed to obtain phosphoric acid ester products having different compositions. For convenience, these are collectively referred to as phosphate esterified product (A). This was used for the production of the following phosphate ester polymers.

(2) Production of phosphate ester polymer (2-1) Examples 2-1 to 2-12, 2-14, 2-15 and Comparative Example 2-1
76.3 g of water was charged into a glass reaction vessel (four-necked flask) equipped with a stirrer, purged with nitrogen while stirring, and heated to 80 ° C. in a nitrogen atmosphere. 130 g of methoxypolyethylene glycol allyl ether (average added mole number of EO: 32.5: AG-325M manufactured by Nippon Emulsifier Co., Ltd.), 51.1 g of phosphoric ester (A) and 0.79 g of 3-mercaptopropionic acid A monomer solution mixed and dissolved in 130 g (pH as shown in Table 4), a solution obtained by dissolving 2.82 g of sodium peroxodisulfate in 45 g of water, and 2.40 g of 35% hydrogen peroxide were mixed and dissolved. The two were added dropwise over 2.0 hours. After aging for 1 hour, a solution prepared by dissolving 1.41 g of sodium peroxodisulfate in 15 g of water and a solution prepared by mixing and dissolving 1.20 g of 35% hydrogen peroxide over 30 minutes were added dropwise over a period of 1.5 hours. Aging at temperature (80 ° C.). After completion of aging, the copolymer was neutralized with 20% sodium hydroxide solution to obtain a copolymer of Example 2-1. In the same manner, copolymers of Examples 2-2 to 2-12, 2-14, 2-15, and Comparative Example 2-1 were produced.

(2-2) Example 2-13
70.9 g of water was charged into a glass reaction vessel (four-necked flask) equipped with a stirrer, purged with nitrogen while stirring, and heated to 55 ° C. in a nitrogen atmosphere. 131 g of polyoxyethylene allyl ether (average added mole number of EO 10.0: AG-110 manufactured by Nippon Emulsifier Co., Ltd.), 33.6 g of phosphoric acid ester (A) and 1.17 g of 3-mercaptopropionic acid are mixed with water. A monomer solution mixed and dissolved in 131 g (pH is as shown in Table 5) and 2,2′-azobis (2-amidinopropane) dihydrochloride (Wako Pure Chemical Industries, Ltd .: V-50 (2, 2′-Azobis (2-methylpropionamidine) dihydrochloride) 9.94 g dissolved in 45 g of water were added dropwise over 2.0 hours, and after aging for 1 hour, 2,2′-azobis (2- Amidinopropane) dihydrochloride (4.97 g) dissolved in water (15 g) was added dropwise over 30 minutes, followed by aging at the same temperature (55 ° C.) for 1.5 hours. To give the copolymer of Example 2-13.

  Tables 4 and 5 summarize Examples 2-1 to 2-15 and Comparative Example 2-1. In addition, pH at the time of reaction (20 degreeC) is a thing at the time of completion | finish of reaction.

<Test Example 2>
Dispersibility and viscosity were evaluated in the same manner as in Example 1 using the copolymers of Tables 4 and 5 obtained in Examples 2-1 to 2-15 and Comparative Example 2-1. The results are shown in Table 6.

  From the results of Table 6, in the phosphate ester polymers of Examples 2-1 to 2-15 copolymerized using a monomer solution having a pH of 7 or less containing monomer 2 and / or monomer 3, It becomes a dispersant excellent in the effect of reducing the viscosity. The monomer 1 / (monomer 2 + monomer 3) charge molar ratio is 5 to 95/95 to 5 with a good balance between dispersibility and viscosity reducing effect, and 20 to 80/80. -20 showed the tendency for a balance to improve further.

<Examples 3-1 to 3-10>
A 300 mL separable flask equipped with a condenser, a stirrer, and a dropping funnel was charged with 120 g (85.9 mmol) of methoxypolyethylene glycol allyl ether (average number of moles of EO added 30 moles), followed by nitrogen substitution. After the temperature was raised to 110 ° C., stirring was started, and after about 10 minutes, 10.4 g of 35% hydrogen peroxide aqueous solution and 23.2 g (20.0 mmol) of 2-hydroxyethyl acrylate (hereinafter also referred to as hydroxyethyl acrylate) ) Was started and added dropwise over 3 hours. After heating for 1 hour, 10.4 g of 35% aqueous hydrogen peroxide was added dropwise over 1 hour. After heating for 1 hour, the mixture was allowed to cool and 65.75 g of polyphosphoric acid was added over 1 hour, followed by stirring at 40 ° C. for 2 hours. 20 mL of water was added, and the mixture was heated and stirred at 80 ° C. for 2 hours to synthesize the copolymer of Example 3-1. In the same manner, Examples 3-2 to 3-6 and Examples 3-8 to 3-10 were synthesized. Further, a part of Example 3-6 was collected and diluted with an appropriate amount of water, and then packed in a cellulose tube (fractional molecular weight: 12000 to 14000). The dialysis was performed while changing the external solution to about 10 L and about every 12 hours. The treatment was performed every day, and the inorganic phosphoric acid contained in Example 3-3 was removed. Then, it concentrated with the evaporator and made pale yellow aqueous solution into Example 3-7.

  The results of Examples 3-1 to 3-10 are summarized in Table 7. The polymerization initiator was used in the molar ratio shown in Table 7 with respect to 100 mol in total of monomer 1 and monomer 4.

<Test Example 3>
Using the copolymer obtained in Example 3, dispersibility and viscosity were evaluated in the same manner as in Example 1 and the like. The results are shown in Table 8.

  From the results in Table 8, it was found that the performance as a dispersant of the phosphate ester polymer obtained by the second production method was obtained and the viscosity reduction effect was excellent. Further, in order to obtain the dispersion performance and the viscosity reduction effect, the polymerization initiator is 15 mol or more, the polymerization temperature is 60 ° C. or more, and the amount of the phosphorylating agent is 1.0 equivalent to the hydroxyl group in the reaction system. It turns out that the above is suitable.

<Test Example 4>
The following concrete test was conducted using a part of the copolymer of the above Example (as shown in Table 10). The results are shown in Table 10. In addition, the sample number in Table 10 shows the number of the said Example.

[Concrete test]
(1) Concrete mix The concrete mix is as shown in Table 9.

The materials used in Table 9 are as follows.
C: Ordinary Portland cement (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: Fine aggregate, mountain sand from Kimitsu, Chiba G: Coarse aggregate, lime crushed stone from Mt. Torigata, Kochi

(2) Preparation of concrete Using a forced biaxial mixer manufactured by IHI as a mixer to be used, concrete was prepared in a concrete volume of 30 liters, stirring time for 10 seconds, and 90 seconds after adding kneaded water. At that time, the addition amount of the copolymer was adjusted so that the slump flow value was 35.0 to 42.0 cm. The slump flow value is an average value of the maximum slump flow value and the slump flow value measured in a direction perpendicular to the length of a half of the line segment giving the maximum value. Table 10 shows the amount of copolymer added necessary to achieve this slump flow. In addition, the slump flow test of concrete is JIS A 1150 (maximum size of coarse aggregate (G) 20 mm, concrete temperature 20-22 ° C., how to pack samples: packed in 3 layers, and each layer with 25 push rods. ). Moreover, the slump test (JIS A 1101) was done about the concrete in the addition amount of the copolymer. Further, the amount of concrete air (JIS A 1128) was adjusted by adding an antifoaming agent or an AE agent so that the amount of entrained air was 3.5 to 5.5% by volume.

(3) Concrete evaluation Concrete compressive strength test method (JIS A 1108, underwater curing, strength for 7 days) was performed. The results are shown in Table 10.

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

Claims (3)

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), pH 7 The manufacturing method of the phosphate ester type polymer copolymerized below.

[Wherein R ¹ and R ² are each a hydrogen atom or a methyl group, R ³ is a hydrogen atom or —CH ₂ O (AO) _n X, AO is an oxyalkylene group or oxystyrene group having 2 to 4 carbon atoms, n is the average addition 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 phosphate ester polymer according to claim 1, wherein the monomer 2 and the monomer 3 are obtained by reacting an organic hydroxy compound represented by the following general formula (4) with a phosphorylating agent. Manufacturing method.

[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 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.

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