阅读说明：本技术 一种双液态磷酸镁材料及其制备方法 (Double-liquid magnesium phosphate material and preparation method thereof ) 是由 钱觉时 张艺 汪宏涛 秦继辉 李振 王帆 于 2020-06-15 设计创作，主要内容包括：本发明公开了一种双液态磷酸镁材料及其制备方法。所述双液态磷酸镁材料包括A液和B液,其中A液由重烧氧化镁、减水剂、增稠剂、超细粉体和水组成；B液由磷酸盐、缓凝剂和水组成。制备方法为：将组成A液和B液的原料分别按照配比称量好,然后分别搅拌均匀制备成A液和B液并密封保存,使用时根据工程需求按不同的A液与B液体积比混合,混合后能发生反应,硬化后形成强度。本发明采用能较长时间保持稳定状态的两个液相,可解决粉体磷酸镁水泥易受潮导致性能下降和失效的问题；能节省粉体磷酸镁水泥现场使用时需准确称量用水的工序,使得施工速度更快；采用双液体可使得混合效率更高,解决粉体磷酸镁水泥需要搅拌时间长而凝结时间过快的不便。(The invention discloses a double-liquid magnesium phosphate material and a preparation method thereof. The double-liquid magnesium phosphate material comprises a solution A and a solution B, wherein the solution A consists of dead burned magnesium oxide, a water reducing agent, a thickening agent, superfine powder and water; the liquid B consists of phosphate, retarder and water. The preparation method comprises the following steps: the raw materials for preparing the liquid A and the liquid B are respectively weighed according to the proportion, then are respectively stirred uniformly to prepare the liquid A and the liquid B, and are stored in a sealed manner. The invention adopts two liquid phases which can keep a stable state for a long time, and can solve the problems of performance reduction and failure caused by the fact that the powder magnesium phosphate cement is easy to be affected with damp; the process of accurately weighing water when the powder magnesium phosphate cement is used on site can be saved, so that the construction speed is higher; the adoption of double liquids can lead the mixing efficiency to be higher, and solve the inconvenience that the powder magnesium phosphate cement needs long stirring time and the setting time is too fast.)

1. A double-liquid magnesium phosphate material is characterized in that the double-liquid magnesium phosphate material is formed by mixing liquid A and liquid B according to a certain volume ratio; wherein the solution A is obtained by weighing and mixing the dead burned magnesium oxide, the water reducing agent, the thickening agent and water according to a ratio, uniformly stirring and sealing; and the liquid B is obtained by weighing and mixing phosphate, retarder and water according to a ratio, uniformly stirring and sealing.

2. The dual-liquid magnesium phosphate material of claim 1, wherein the ratio of the solution A comprises: the water-solid ratio is 0.1-0.6, the addition amount of the water reducing agent is 0-5% of the mass of the dead burned magnesia, and the addition amount of the thickening agent is 0.01-2% of the mass of the dead burned magnesia; the proportion of the solution B comprises: the water-solid ratio is 0.05-0.6, and the addition amount of the retarder is 0-50% of the mass of the phosphate; the volume ratio of the solution A to the solution B is (0.5-4): 1.

3. the dual-liquid magnesium phosphate material of claim 1 or 2, wherein the solution A is further doped with ultrafine powder, the doping amount of the ultrafine powder is 0-20% of the mass of the dead burned magnesium oxide, the ultrafine powder is at least one of nano silica, nano clay minerals, ultrafine fly ash and finely-ground calcined kaolin, and the particle size of at least 80% of the ultrafine powder is less than 10 μm.

4. The dual liquid magnesium phosphate material of claim 1 or 2, wherein the dead burned magnesium oxide has a particle size of less than 100 μm, and wherein at least 40% of the dead burned magnesium oxide has a particle size of less than 50 μm.

5. The biliquid magnesium phosphate material of claim 1 or claim 2, wherein the water reducing agent is at least one of a polycarboxylic acid water reducing agent, a naphthalene water reducing agent, and a lignosulfonate water reducing agent.

6. The biliquid magnesium phosphate material of claim 1 or 2, wherein the thickener is at least one of hydroxypropyl methylcellulose and hydroxyethyl cellulose.

7. The dual liquid magnesium phosphate material of claim 1 or 2, wherein the phosphate is at least one of monoammonium phosphate, monopotassium phosphate, monosodium phosphate, diammonium phosphate, dipotassium phosphate, disodium phosphate.

8. The biliquid magnesium phosphate material of claim 1 or 2, wherein the retarder is at least one of borax, boric acid or sodium tripolyphosphate.

9. A preparation method of a double-liquid magnesium phosphate material is characterized in that the preparation method of the double-liquid magnesium phosphate material as claimed in any one of claims 1 to 8 comprises the following steps:

(1) preparation of solution A: firstly, uniformly dispersing the weighed dead burned magnesium oxide, the water reducing agent and water in a high-speed stirring manner, then adding the thickening agent, stirring at a low speed until suspension is prepared, and then sealing and storing;

(2) and (3) preparation of a liquid B: mixing the weighed phosphate, retarder and water at the temperature of 10 ℃ or higher, stirring at a high speed, standing for not less than 1 hour, and then stirring at a low speed until suspension is prepared, and then sealing and storing.

10. The method for preparing a biliquid magnesium phosphate material of claim 9, wherein the ultrafine powder is added to the weighed dead burned magnesium oxide, the water reducing agent and water, and then mixed, and uniformly dispersed by high-speed stirring.

Technical Field

The invention relates to the technical field of building materials, in particular to a double-liquid magnesium phosphate material and a preparation method thereof.

Background

Magnesium Phosphate Cement (MPC) is a special cementing material which is prepared by mixing re-burned Magnesium oxide, phosphoric acid or acid Phosphate and retarder according to a proper proportion, adding water to make acid-alkali neutralization reaction, coagulating and hardening to produce strength. The dead burned magnesia is usually sintered magnesia obtained by calcining magnesite at a high temperature of 1300-1700 ℃. The phosphate salts generally include monohydrogen and dihydrogen phosphate salts, which primarily provide phosphate and hydrogen ions for the reaction, which can react with magnesium oxide to form struvite. Commonly used retarders are boron compounds such as borax, boric acid, and the like. The magnesium phosphate cement is used as a cementing material, has the property of chemically combined ceramic, has a series of performances such as good fluidity, fast setting and hardening, high early strength, good bonding property, good volume stability, excellent wear resistance and salt erosion resistance and the like compared with common portland cement, is widely applied to the fast repair of roads, bridges and airport runways, the solidification of harmful and radioactive substances and the like, and has important civil and military applications. The MPC has excellent performance, has unique advantages in the aspects of rapid first-aid repair, engineering repair and rush-construction, has very important application value and military significance in the aspects of rapid construction of national defense engineering and military airports and first-aid repair and recovery of engineering facilities, and also has wide application prospect in the aspects of rapid repair of projects such as bridge wharfs, civil house buildings, civil airport runways, factory building facilities, municipal arterial roads, expressways and the like.

However, in the practical application of the existing magnesium phosphate cement, a series of problems still remain to be solved. The short setting time of MPC is both an advantage and a disadvantage, especially the setting time of MPC is faster under high temperature environment and there is a problem of insufficient operation time of site construction. Magnesium phosphate cement is usually in the form of single-component powder or double-component powder products, and magnesium phosphate cement powder is easy to damp and agglomerate when stored, so that the product performance is influenced, and even the magnesium phosphate cement powder fails; when the powder magnesium phosphate cement is used, water needs to be added, but the water consumption needs to be strictly controlled, the flowability and the strength of the magnesium phosphate cement are greatly influenced due to the small change of the water consumption, the construction speed is influenced due to the increase of the working procedure caused by weighing the water when the powder magnesium phosphate cement is used on site, and the fluctuation of the actual water consumption is easily caused.

The powder magnesium phosphate cement, including the bi-component powder magnesium phosphate cement, is added with water when in use, and the uniformity and the quality of the magnesium phosphate cement when in use are difficult to ensure under many conditions, because acid-base components forming the magnesium phosphate cement need to be dissolved for a certain time and then participate in the reaction, but the magnesium phosphate cement reacts quickly, and the dissolution degree of main components of the magnesium phosphate cement after the magnesium phosphate cement is coagulated and hardened is reduced quickly. Therefore, when the powder magnesium phosphate cement is used, the problem that the construction operation time is insufficient due to long time and short setting time for uniformly stirring and mixing after adding water is often encountered.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a double-liquid magnesium phosphate material, which adopts a double-liquid mode to solve the problems that the powdery magnesium phosphate cement has harsh storage conditions, more preparation procedures, large water consumption fluctuation, long stirring time and difficulty in adapting to a rapid setting and hardening place in the practical application process.

The invention also provides a preparation method of the double-liquid magnesium phosphate material, which can ensure that the double-liquid magnesium phosphate material which has a suspended state and can be stored for a long time is prepared.

In order to achieve the purpose, the invention adopts the following technical scheme: a double-liquid magnesium phosphate material is prepared by mixing liquid A and liquid B according to a certain volume ratio; wherein the solution A is obtained by weighing and mixing the dead burned magnesium oxide, the water reducing agent, the thickening agent and water according to a ratio, uniformly stirring and sealing; and the liquid B is obtained by weighing and mixing phosphate, retarder and water according to a ratio, uniformly stirring and sealing.

Further, the solution A is prepared by mixing the dead burned magnesium oxide, the water reducing agent, the thickening agent, the superfine powder and water according to the proportion. The liquid A is added with the thickening agent and is also doped with the superfine powder to form fine particle suspension, which is beneficial to keeping the suspension of thicker magnesium oxide particles, and then the uniformity of the liquid A is improved by fully stirring, so that the liquid A can keep a suspension state for a long time without sedimentation and hardening. Retarder, phosphate and water are uniformly stirred and mixed at a high speed according to a specific proportion to prepare liquid B, the phosphate, the retarder and the water are uniformly stirred at a high speed at a temperature of more than or equal to 10 ℃, the phosphate and borax are partially dissolved in the water, the phosphate and borax particles are thinned, the solid-liquid density difference is greatly reduced, and meanwhile, the dissolved phosphate and borax serve as thickener and dispersant, so that the liquid B can be stored for a long time in a stable suspension state. When the double-liquid magnesium phosphate material is used on site, the double-liquid magnesium phosphate material is mixed according to a certain volume ratio of the liquid A to the liquid B, the volume ratio of the liquid A to the liquid B is usually (0.5-4): 1, and the use requirements of most practical projects can be met.

The solution A used in the invention is prepared by mixing heavy calcined magnesia powder, superfine powder, a water reducing agent, a thickening agent and water in proportion. The particle size of the dead burned magnesia is less than 100 mu m, wherein at least 40% of the dead burned magnesia has a particle size of less than 50 mu m, the water-solid ratio of the prepared solution A is 0.1-0.6, the addition amount of the water reducing agent is 0-5% of the mass of the dead burned magnesia, the addition amount of the thickening agent is 0.01-2% of the mass of the dead burned magnesia, the addition amount of the superfine powder is 0-20% of the mass of the dead burned magnesia, and the prepared solution A can keep the stable state of the suspension for a long time under normal temperature and pressure.

The particle size of the dead burned magnesia is preferably 10-75 mu m when the liquid A is prepared, wherein the particle size of at least 80% of the dead burned magnesia is less than 50 mu m, the water-solid ratio of the prepared liquid A is preferably 0.18-0.4, the doping amount of the water reducing agent is preferably 0.2-1% of the mass of the dead burned magnesia, the doping amount of the thickening agent is preferably 0.01-1% of the mass of the dead burned magnesia, the doping amount of the superfine powder is preferably 1-3% of the mass of the dead burned magnesia, the liquid A prepared by the mixture ratio is further preferably good in flowability and stability, and finally the prepared liquid A is stored in a sealed mode.

The preparation method of the solution A comprises the following steps: firstly, grinding and screening the dead burned magnesia, then mixing the screened dead burned magnesia, the water reducing agent, the superfine powder and water, uniformly stirring the mixture by using a high-speed stirrer (the high-speed stirring rotating speed is more than 300 r/min), then adding the thickening agent, uniformly stirring the mixture at a low speed (the low-speed stirring rotating speed is less than 100 r/min) to obtain a magnesia suspension liquid with good fluidity and stability, and finally, sealing and storing the prepared liquid A.

The liquid B used by the invention is prepared by mixing phosphate powder, a retarder and water in proportion, wherein the water-solid ratio of the liquid B is 0.05-0.6, the addition amount of the retarder is 0-50% of the mass of phosphate, and the prepared liquid B can keep the stable state of a suspension for a long time at normal temperature and normal pressure.

When the liquid B is prepared, the phosphate can be preferably compounded by ammonium dihydrogen phosphate and potassium dihydrogen phosphate, the water-solid ratio can be preferably 0.15-0.3, the retarder can be preferably borax, the doping amount of the borax is preferably 6-20% of the mass of the phosphate, the liquid B obtained by further preferably proportioning is good in fluidity and stability, and finally the prepared liquid B is stored in a sealed manner.

The preparation method of the solution B comprises the following steps: the finely ground phosphate, the retarder and water are mixed in proportion at the temperature of more than or equal to 10 ℃, stirred at high speed (the high-speed stirring rotating speed is more than 300 r/min) uniformly, kept stand for not less than 1 hour, and stirred at low speed (the low-speed stirring rotating speed is less than 100 r/min) uniformly to obtain the phosphate suspension with better fluidity and stability.

The invention can adjust the volume ratio of the liquid A to the liquid B according to different environmental conditions, different positions and different performance requirements of actual engineering to obtain the magnesium phosphate material with excellent flow property, mechanical property and bonding property, thereby meeting the use requirements of different actual engineering.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention creatively provides the double-liquid magnesium phosphate material, so that the main components forming the magnesium phosphate cement are fully dissolved to form very fine suspended particles, and the two liquid components can fully react when being slightly mixed, thereby being beneficial to the improvement of the performance of the magnesium phosphate material and the reduction of the dosage of the effective components of the magnesium phosphate material. The double-liquid magnesium phosphate material does not need to measure moisture when in use, only needs to mix A, B two liquid components, and the time for mixing powder to reach a sufficient degree is shorter because A, B two liquid components are suspension liquid with fine particles.

2. The invention is stored in a double-liquid form of the liquid A and the liquid B before use, is formed by mixing the liquid A and the liquid B according to a certain volume ratio when in use, and can be mixed and used according to the volume ratio of required performance when in actual engineering application. Wherein, A liquid and B liquid are the tiny suspension of granule liquid state, and not only the short time just can stir fully to it is more abundant to take place the reaction degree in the short time, satisfies early strength requirement, and adds water again when powder magnesium phosphate cement uses, need longer churning time just can the misce bene, and ambient temperature is higher and use very inconveniently when the construction volume is big. The liquid A and the liquid B can be uniformly mixed within 30s, the subsequent sufficient construction operation time of practical engineering application can be fully ensured, and the problem that the construction operation time is insufficient due to the overlong stirring time required by the powder magnesium phosphate cement is solved.

3. In the invention, the liquid A and the liquid B can be used only by mixing according to the volume ratio during construction, the use is more convenient, and the problems of multiple on-site preparation procedures and inconvenient construction operation of the powdery magnesium phosphate cement are avoided.

4. The liquid A and the liquid B have good stability, can be stored for a long time at normal temperature and normal pressure without changing the basic properties, have long storage period, and avoid the problems that the magnesium phosphate cement is easy to damp and agglomerate during storage and the product performance is influenced.

5. The magnesium phosphate material prepared by mixing the solution A and the solution B greatly shortens the time required by uniformly stirring the magnesium phosphate cement, and the setting time can be controlled to be very short, so that the magnesium phosphate material is suitable for the actual engineering use requirement with high early strength.

6. The magnesium phosphate material prepared by mixing the solution A and the solution B is also suitable for grouting, grouting and other modes, can be used along with mixing, and can realize continuous mixed pouring.

Detailed Description

The present invention will be further described with reference to the following examples.