CN113461357B - Retarding type efficient dispersant for phosphorus-magnesium material and preparation method thereof - Google Patents

Retarding type efficient dispersant for phosphorus-magnesium material and preparation method thereof Download PDF

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CN113461357B
CN113461357B CN202110744804.2A CN202110744804A CN113461357B CN 113461357 B CN113461357 B CN 113461357B CN 202110744804 A CN202110744804 A CN 202110744804A CN 113461357 B CN113461357 B CN 113461357B
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water
phosphorus
dispersing
water reducing
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CN113461357A (en
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高育欣
余保英
孔亚宁
刘明
杨文�
程宝军
祝小靓
李毅
周建伟
王军
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Building Materials Science Research Institute Co Ltd of China West Construction Group Co Ltd
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Building Materials Science Research Institute Co Ltd of China West Construction Group Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
    • C04B40/0028—Aspects relating to the mixing step of the mortar preparation
    • C04B40/0039—Premixtures of ingredients
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
    • C04B2103/20—Retarders
    • C04B2103/22—Set retarders
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
    • C04B2103/40—Surface-active agents, dispersants
    • C04B2103/408—Dispersants

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Colloid Chemistry (AREA)

Abstract

The invention discloses a retarding high-efficiency dispersing agent for phosphorus-magnesium materials and a preparation method thereof, wherein the dispersing agent comprises a coagulation regulating component, a dispersing component, a water reducing component and water, and the mass ratio of the coagulation regulating component to the dispersing component to the water is (1-0.5-2); the coagulation regulating component is small molecular boric acid inorganic salt or citric acid; the dispersed component is macromolecular organic polyelectrolyte; the water reducing component is at least one of sorbitol, glyceryl hydroxystearate, glyceryl monostearate, glyceryl distearate and glyceryl tristearate. The dispersing agent can effectively solve the problems of poor regulating and controlling effect on the setting time of the phosphorus-magnesium material and poor water reducing effect of the existing dispersing agent.

Description

Retarding type efficient dispersing agent for phosphorus-magnesium material and preparation method thereof
Technical Field
The invention relates to the technical field of dispersing agents, and particularly relates to a retarding type efficient dispersing agent for a phosphorus-magnesium material and a preparation method thereof.
Background
The phosphorus-magnesium material is based on magnesium-containing alkaline oxide and phosphorus-containing inorganic salt, is quickly coagulated and hardened in water environment to form a high-early-strength cementing material, has the excellent characteristics of good bonding strength, small shrinkage deformation, high durability and the like, and has wide prospects in the fields of road repair, material packaging, metal corrosion prevention and the like.
However, the water cement ratio of the existing phosphorus-magnesium material is relatively fixed, and in order to improve the fluidity, the water cement ratio is usually improved, and the condensation hardening time of the existing phosphorus-magnesium material is too fast, particularly the condensation time is even less than 10 minutes at high temperature in summer, so that the operational time of construction is too short, and the popularization and application of the phosphorus-magnesium material are limited. In order to improve the working performance of the mixture of the phosphorus and magnesium materials and adjust the setting time of the mixture, researchers at home and abroad carry out researches on the aspects of a water reducing agent and a performance adjusting additive of the phosphorus and magnesium materials.
The prior dispersing agent has poor regulation and control effect on the retarding time of the phosphorus-magnesium material and poor water reducing effect.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a retarding type efficient dispersant for a phosphorus-magnesium material and a preparation method thereof, and the dispersant can effectively solve the problems of poor regulating and controlling effect on the setting time of the phosphorus-magnesium material and poor water reducing effect of the existing dispersant.
In order to achieve the purpose, the technical scheme adopted by the invention for solving the technical problems is as follows:
a retarding high-efficiency dispersing agent for phosphorus-magnesium materials comprises a coagulation adjusting component, a dispersing component, a water reducing component and water, wherein the mass ratio of the coagulation adjusting component to the dispersing component to the water reducing component to the water is 1.5-2;
the coagulation regulating component is micromolecular boric acid inorganic salt or citric acid;
the dispersed component is macromolecular organic polyelectrolyte;
the water reducing component is at least one of sorbitol, glyceryl hydroxystearate, glyceryl monostearate, glyceryl distearate and glyceryl tristearate.
Further, the mass ratio of the coagulation regulating component to the dispersing component to the water reducing component to water is 1.2.
According to the scheme, the coagulation regulating component, the dispersing component and the water reducing component are arranged and are used in a composite mode according to the mass ratio, the retarding effect is achieved, the good dispersing effect of the phosphorus-magnesium material is achieved, sufficient operable time is provided for construction, and the uniform dispersing effect is achieved.
Further, the set adjusting component comprises at least one of sodium tetraborate, potassium citrate and sodium citrate.
Further, the coagulation regulating component comprises sodium tetraborate and potassium tetraborate, and the mass ratio of the sodium tetraborate to the potassium tetraborate is 1.
Further, the dispersing component includes at least one of sodium polyacrylate and sodium polymethacrylate.
Further, the dispersing component is sodium polyacrylate and sodium polymethacrylate, and the mass ratio of the sodium polyacrylate to the sodium polymethacrylate is 1.
Further, the water reducing component comprises sorbitol, glyceryl hydroxystearate, glyceryl monostearate, glyceryl distearate and glyceryl tristearate, wherein the mass ratio of the sorbitol to the glyceryl hydroxystearate to the glyceryl monostearate to the glyceryl distearate to the glyceryl tristearate is 1:0.5-2.
Further, the preparation method of the retarding high-efficiency dispersing agent for the phosphorus-magnesium material comprises the following steps:
(1) Heating water to 55-65 deg.C, adding coagulation regulating component, and stirring to dissolve;
(2) Adding the dispersing component into the solution obtained in the step (1), stirring and dissolving, and standing for 20-40min at constant temperature;
(3) And (3) adding a water reducing component into the solution obtained in the step (2), and carrying out ultrasonic treatment for 5-10min to obtain the water reducing agent.
Further, the preparation method of the retarding high-efficiency dispersing agent for the phosphorus-magnesium material comprises the following steps:
(1) Fully emulsifying the dispersed components and water in water bath environment at 55-65 deg.C for 25-35min;
(2) Adding a water reducing component into the solution obtained in the step (1), and carrying out ultrasonic treatment for 5-10min;
(3) And (3) adding the coagulation regulating component into the solution in the step (2), and stirring until the coagulation regulating component is dissolved to obtain the product.
The beneficial effects brought by the invention are as follows:
because the phosphorus-magnesium material contains a large amount of Mg 2+ ，Mg 2+ With B in the coagulation-regulating component 4 O 7 2- The combination of the amorphous substance on the surface of the magnesium oxide particles of the phosphorus-magnesium material prevents the magnesium oxide from hydrolyzing to release Mg 2+ And the temperature of the system is reduced and the pH value is increased by adjusting, so that the hydration reaction is delayed. The use of the coagulation regulating component adjusts the hydration rate, is more beneficial to the exertion of the effect of the dispersing agent, provides sufficient time for the forming of the phosphorus-magnesium material, is beneficial to the effects of sufficient dispersion and uniform system of the phosphorus-magnesium material particles, achieves better water reducing effect and provides more operable time for the construction stirring.
The macromolecular organic polyelectrolytes in the dispersing component all contain carboxyl groups, and the carboxyl groups can absorb the charges on the surface of the phosphorus-magnesium material, prevent the material from aggregating, facilitate the particle dispersion and improve the dispersing effect.
The esters in the water reducing component have a hydrophobic function, so that the surface tension of the slurry can be reduced, the frictional resistance among the phosphorus-magnesium material particles can be reduced, and the function of reducing the viscosity of the slurry can be realized.
The coagulation regulating component, the dispersing component and the water reducing component are used in a composite mode according to the mass ratio, so that the retarding effect is achieved, the good dispersing effect of the phosphorus-magnesium material is achieved, sufficient operable time is provided for construction, and the uniform dispersing effect is achieved.
Detailed Description
Example 1
A retarding high-efficiency dispersing agent for phosphorus-magnesium materials comprises a coagulation adjusting component, a dispersing component, a water reducing component and water, wherein the mass ratio of the coagulation adjusting component to the dispersing component to the water reducing component to the water is 1.5; the coagulation regulating component is sodium citrate, the dispersing component is sodium polyacrylate, and the water reducing component is sorbitol.
The preparation method of the retarding type efficient dispersant for the phosphorus-magnesium material comprises the following steps:
(1) Heating water to 60 deg.C, adding sodium citrate, and dissolving completely;
(2) Adding sodium polyacrylate into sodium citrate solution, stirring thoroughly, dissolving, and keeping constant temperature for 30 min;
(3) And (3) adding sorbitol into the mixture obtained in the step (2), and performing ultrasonic treatment for 10 minutes to obtain the retarding efficient dispersing agent for the phosphorus-magnesium material.
Example 2
The retarding efficient dispersing agent for the phosphorus-magnesium material comprises a coagulation adjusting component, a dispersing component, a water reducing component and water, wherein the mass ratio of the coagulation adjusting component to the dispersing component to the water reducing component to the water is 1; the coagulation regulating component is potassium citrate, the dispersing component is sodium polymethacrylate, and the water reducing component is glyceryl hydroxystearate.
The preparation method of the retarding type efficient dispersant for the phosphorus-magnesium material comprises the following steps:
(1) Heating water to 60 ℃, adding potassium citrate, and fully dissolving;
(2) Adding sodium polymethacrylate into the potassium citrate solution, fully stirring and dissolving, and keeping the temperature for 30 minutes;
(3) And (3) adding the hydroxystearic acid glyceride into the mixture obtained in the step (2), and performing ultrasonic treatment for 10 minutes to obtain the retarding efficient dispersing agent for the phosphorus-magnesium material.
Example 3
A retarding type efficient dispersing agent for phosphorus-magnesium materials comprises a coagulation regulating component, a dispersing component, a water reducing component and water, wherein the mass ratio of the coagulation regulating component to the dispersing component to the water reducing component to the water is 1; the coagulation regulating component is sodium tetraborate, the dispersing component is sodium gluconate, and the water reducing component is glyceryl monostearate.
The preparation method of the retarding type efficient dispersant for the phosphorus-magnesium material comprises the following steps:
(1) Fully dispersing sodium gluconate in a water bath environment at 60 ℃ for about 30 minutes;
(2) Adding glyceryl monostearate into the mixture obtained in the step (1), and jointly performing ultrasonic treatment for 10 minutes;
(3) And (3) adding sodium tetraborate into the mixture obtained in the step (2), and fully dissolving to obtain the retarding type efficient dispersing agent for the phosphorus-magnesium material.
Example 4
A retarding type efficient dispersant for phosphorus-magnesium materials comprises a coagulation adjusting component, a dispersing component, a water reducing component and water, wherein the mass ratio of the coagulation adjusting component to the dispersing component to the water reducing component to the water is 1.5; the coagulation regulating component is potassium tetraborate, the dispersing component is sodium polyacrylate, and the water reducing component is glyceryl distearate.
The preparation method of the retarding type efficient dispersant for the phosphorus-magnesium material comprises the following steps:
(1) Fully dispersing sodium polyacrylate in a water bath environment at 60 ℃ for about 30 minutes;
(2) The glyceryl distearate is added into the mixture in the step (1), and the mixture is subjected to ultrasonic treatment for 10 minutes;
(3) And (3) adding potassium tetraborate into the mixture obtained in the step (2), and fully dissolving to obtain the retarding type efficient dispersing agent for the phosphorus-magnesium material.
Example 5
A retarding type efficient dispersant for phosphorus-magnesium materials comprises a coagulation adjusting component, a dispersing component, a water reducing component and water, wherein the mass ratio of the coagulation adjusting component to the dispersing component to the water reducing component to the water is 1.5; the coagulation regulating component is potassium tetraborate, the dispersing component is sodium polyacrylate, and the water reducing component is tristearin.
The preparation method of the retarding type efficient dispersant for the phosphorus-magnesium material comprises the following steps:
(1) Fully dispersing sodium polyacrylate in a water bath environment at 60 ℃ for about 30 minutes;
(2) The glyceryl tristearate is mixed in the step (1) and the mixture is subjected to common ultrasonic treatment for 10 minutes;
(3) And (3) adding potassium tetraborate into the mixture obtained in the step (2), and fully dissolving to obtain the retarding type efficient dispersing agent for the phosphorus-magnesium material.
Example 6
A retarding type efficient dispersant for phosphorus-magnesium materials comprises a coagulation adjusting component, a dispersing component, a water reducing component and water, wherein the mass ratio of the coagulation adjusting component to the dispersing component to the water reducing component to the water is 1.2; the coagulation regulating component is prepared by compounding sodium citrate, potassium citrate, sodium tetraborate and potassium tetraborate according to a mass ratio of 1.
The preparation method of the retarding type efficient dispersant for the phosphorus-magnesium material comprises the following steps:
(1) Fully dispersing the three components in a water bath environment at 60 ℃ for about 30 minutes;
(2) Adding a water reducing component into the mixture obtained in the step (1), and carrying out ultrasonic treatment for 10 minutes together;
(3) And (3) adding the coagulation regulating component into the mixture obtained in the step (2), and fully dissolving to obtain the retarding type efficient dispersing agent for the phosphorus-magnesium material.
Test examples
The performance of the dispersants prepared in examples 1-6 were tested separately, the specific test procedure was as follows:
the experimental method comprises the following steps:
the setting time test refers to GBT1346-2019 inspection method for water consumption, setting time and stability of standard consistency of cement;
in the mortar fluidity test, a glass plate is adopted to replace a jumping table, jumping and leveling are not needed, the mortar is allowed to expand freely, the maximum expansion diameters of two vertical aspects of the mortar are tested by referring to GB/T2419 'Cement mortar flow determination method', and the average value is calculated;
and (3) testing mechanical properties: the compressive strength and the flexural strength of the cement of a prism entity with the size of 40mm multiplied by 160mm are determined, and reference is made to GB/T1767 'cement mortar strength test method'. The specific test results are shown in tables 1-3.
Table 1: comparison of the Effect of the dispersant in the application of phosphorus-magnesium neat paste Material
Figure SMS_1
Figure SMS_2
As can be seen from the data in the table above, when the fluidity of the phosphorus-magnesium material net slurry reaches about 150/mm, the water-cement ratio of the dispersant added in the examples 1-6 is lower than that of the dispersant not added, which proves that the water addition amount can be effectively reduced after the dispersant is added.
Table 2: comparison of the effects of the dispersant in phosphorus-magnesium neat paste materials
Figure SMS_3
Figure SMS_4
As can be seen from the data in the table above, the water reducing rate of the phosphorus-magnesium neat paste added with the dispersant in the examples 1-6 reaches 11% -30%, the initial setting time is prolonged by 2-15 minutes relative to the initial setting time without the dispersant, and the compressive strength after 2 hours, 1 day and 28 days is equivalent to or even greater than that without the dispersant.
Table 3: comparison of effects of the dispersant in phosphorus-magnesium mortar materials
Figure SMS_5
Figure SMS_6
As can be seen from the data in the table above, when the fluidity of the phosphorus-magnesium material mortar reaches about 220/mm, the water-cement ratio of the dispersant added in the examples 1-6 is lower than that of the dispersant not added, which proves that the water addition amount can be effectively reduced after the dispersant is added.
Table 4|: comparison of effects of dispersing agent in phosphorus-magnesium mortar material
Figure SMS_7
As can be seen from the data in the table above, the water reducing rate of the phosphorus-magnesium neat paste added with the dispersing agent in the examples 1-6 reaches 10% -30%, the initial setting time is prolonged by 2-12 minutes relative to the initial setting time without the dispersing agent, and the compressive strength after 2 hours, 1 day and 28 days is equivalent to or even greater than that without the dispersing agent.

Claims (3)

1. The retarding type efficient dispersing agent for the phosphorus-magnesium material is characterized by comprising a coagulation regulating component, a dispersing component, a water reducing component and water, wherein the mass ratio of the coagulation regulating component to the dispersing component to the water reducing component to the water is 1.2;
the coagulation regulating component is at least one of potassium citrate and sodium citrate;
the dispersion component is macromolecular organic matter polyelectrolyte; the dispersion component comprises sodium polyacrylate and sodium polymethacrylate, and the mass ratio of the sodium polyacrylate to the sodium polymethacrylate is 1;
the water reducing component comprises sorbitol, glyceryl hydroxystearate, glyceryl monostearate, glyceryl distearate and glyceryl tristearate, wherein the mass ratio of the sorbitol to the glyceryl hydroxystearate to the glyceryl monostearate to the glyceryl distearate to the glyceryl tristearate is 1.5-2.
2. The preparation method of the retarding efficient dispersant for phosphorus-magnesium materials as claimed in claim 1, characterized by comprising the following steps:
(1) Heating water to 55-65 deg.C, adding coagulation regulating component, and stirring to dissolve;
(2) Adding the dispersing component into the solution obtained in the step (1), stirring and dissolving, and standing for 20-40min at constant temperature;
(3) And (3) adding a water reducing component into the solution obtained in the step (2), and carrying out ultrasonic treatment for 5-10min to obtain the water reducing agent.
3. The preparation method of the retarding efficient dispersant for phosphorus-magnesium materials as claimed in claim 1, characterized by comprising the following steps:
(1) Fully emulsifying the dispersed components and water in water bath environment at 55-65 deg.C for 25-35min;
(2) Adding a water reducing component into the solution obtained in the step (1), and carrying out ultrasonic treatment for 5-10min;
(3) And (3) adding the coagulation regulating component into the solution in the step (2), and stirring until the coagulation regulating component is dissolved to obtain the composite material.
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US20080139701A1 (en) * 2004-12-02 2008-06-12 Sika Ltd Powdered Polycarboxylic Acid-Based Cement Dispersant and Dispersant Composition Containing the Dispersant
CN101215116A (en) * 2007-12-27 2008-07-09 同济大学 Retardation setting type polycarboxylic acids series water reducing agent
US10155209B2 (en) * 2013-08-01 2018-12-18 Nippon Paper Industries Co., Ltd. Dispersant
CN109020419B (en) * 2018-08-20 2020-10-09 湖北大学 Tunnel inverted arch superfine inorganic grouting material and preparation method thereof
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