Preparation method of suspending agent and application of suspending agent in magnesium oxide modified cement

Abstract

The invention discloses a preparation method of a suspending agent and application of the suspending agent in magnesium oxide modified cement, a foaming agent and water are mixed, magnesium sulfate is added into the mixed solution, and the suspending agent is obtained after the solution is fully fused by stirring. The prepared suspending agent has excellent temperature response performance, conversion between a suspended state and a gel state can be achieved through simple heating or cooling operation, and great convenience is brought to accurate regulation and control of the material state in practical application; a highly dispersed state of insoluble solid particles in water can be maintained at normal temperature, agglomeration and rapid precipitation of the particles are effectively prevented, and it is ensured that suspension liquid keeps uniformity and stability for a long time; in the application in the field of cement modification, magnesium oxide can be highly uniformly distributed in a cement matrix, the basic performance of cement is kept stable, the mass of the cement is remarkably reduced, the consumption cost of raw materials is directly reduced, and excellent heat insulation performance is shown.

Description

Technical Field

[0001] The invention relates to the field of chemical technology, and in particular to a preparation method of a suspending agent and application of the suspending agent in magnesium oxide modified cement. Background Art

[0002] Effective dispersion of poorly soluble solid particles in water has always been a critical and complex challenge in the fields of chemistry, materials science and industrial applications. Due to strong interactions between particles, such as van der Waals forces, electrostatic effects and hydrophobic effects, these particles tend to spontaneously agglomerate, making it difficult to form a stable and uniform suspension system in aqueous media. This agglomeration phenomenon not only limits the effective surface area of ​​the particles, reduces the reactivity and performance, but also accelerates the sedimentation rate of the particles, seriously restricting the long-term stability of the suspension.

[0003] In the field of building materials, cement modification technology is crucial to promoting a leap in concrete performance. As a core element in this process, the introduction of admixtures has opened up new ways to comprehensively improve cement performance, especially in terms of enhancing mechanical properties, extending durability, and optimizing working performance.

[0004] Magnesium oxide powder, as a typical insoluble particulate admixture, forms agglomerates that are difficult to break in water and quickly settles to the bottom over time. This phenomenon not only greatly limits the effective amount of magnesium oxide added, resulting in a significant reduction in its actual contribution to the cement matrix, but also causes unstable fluctuations in the performance of cement-based materials, posing a severe challenge to product quality control.

[0005] What is more serious is that the uneven distribution of magnesium oxide particles in cement can also trigger a series of chain reactions. These agglomerates are like "islands" in the cement paste, which not only weaken the internal bonding of the material, but also leave potential defects during the curing process, becoming a key factor in reducing mechanical properties and durability. During long-term use, these defects may gradually expand, eventually leading to a decline in the overall performance of cement-based materials.

[0006] Therefore, it is particularly important to develop an efficient and stable suspension technology for insoluble solid particles such as magnesium oxide. Summary of the invention

[0007] In view of the technical problems existing in the prior art, the purpose of the present invention is to provide a suspending agent, which can significantly optimize the dispersion effect of insoluble solid particles in water, effectively avoid the performance limitation caused by agglomeration and rapid precipitation, thereby ensuring that the prepared suspension has long-term optical transmittance and stability. At the same time, in the application of magnesium oxide modified cement, the suspending agent can promote the highly uniform distribution of magnesium oxide particles in the cement matrix, thereby improving the thermal insulation performance of the cement material.

[0008] A method for preparing a suspension agent is characterized in that a foaming agent is mixed with water, magnesium sulfate is added to the mixed solution, and the mixture is stirred sufficiently to obtain the suspension agent.

[0009] Furthermore, the method further comprises the following steps: adding sodium chloride to the mixed solution after adding magnesium sulfate, wherein the amount of sodium chloride added is 5-7% of the mass of the mixed solution.

[0010] Furthermore, the mass ratio of the foaming agent to water is 1 to 2:1.

[0011] Furthermore, the amount of magnesium sulfate added is 30-40% of the mass of the mixed solution.

[0012] Furthermore, the magnesium sulfate is added to the mixed solution in multiple times, and is quickly stirred for uniformity after each addition; more preferably, the magnesium sulfate is added to the mixed solution three times, with 45% of the magnesium sulfate added in the first addition, 30% in the second and third additions, and 25% in the third addition, respectively, and is quickly stirred for 1 minute after each addition.

[0013] Furthermore, the foaming agent is a plant protein foaming agent.

[0014] Furthermore, the foaming power of the foaming agent is greater than 150 mL.

[0015] The present invention also provides a method for applying a suspending agent in magnesium oxide modified cement, which is characterized by comprising the following steps:

[0016] S1: Preparation of intermediate solution: adding magnesium oxide to the suspending agent at a mass ratio of 1:1-2 and stirring evenly, and maintaining for 24-48 hours to obtain an intermediate solution;

[0017] S2: Preparation of magnesium oxide suspension, adding the intermediate solution into the dispersion solvent at a volume ratio of 1:1 to 10 and stirring evenly to obtain a colloidal fluid liquid, namely, magnesium oxide suspension;

[0018] S3: adding magnesium oxide externally, adding the magnesium oxide suspension into the cement mixing process.

[0019] Furthermore, the dispersing solvent is water or 5-7% sodium chloride solution.

[0020] Furthermore, the amount of magnesium oxide added is 5% to 10% of the mass of cement.

[0021] In summary, the present invention has the following beneficial effects:

[0022] First, the suspension prepared by the present invention exhibits excellent temperature response performance, can maintain a stable dispersed suspension state at room temperature, and transform into a colloidal state when the temperature drops below 20°C. The reversible conversion between these two states can be easily achieved through simple heating or cooling operations, which greatly facilitates the precise regulation of the material state in practical applications.

[0023] Second, the suspension prepared by the present invention can maintain a highly dispersed state of insoluble solid particles in water at room temperature, effectively preventing the agglomeration and rapid precipitation of particles, and ensuring that the suspension maintains uniformity and stability for a long time. This feature enables the suspension to be efficiently applied in many fields and scenarios. For example, its good dispersibility can significantly improve the quality of products such as coatings and paints; by optimizing the dispersion state of reactants, it accelerates the chemical reaction process and promotes efficient and controllable production processes; in the field of electronic materials, it helps to evenly distribute the internal structure of electronic materials, thereby significantly improving the electrical conductivity and thermal conductivity of the materials.

[0024] Third, in the application of cement modification, the use of the suspending agent enables the magnesium oxide particles to be highly evenly distributed in the cement matrix, while maintaining the basic properties of cement, it also achieves a significant reduction in the weight of the cement sample, which helps to reduce the cost of raw materials, improve production efficiency, and significantly reduce carbon emissions in the cement production process. In particular, in the heat transfer effect test, the cement sample prepared by adding magnesium oxide using the method of the present invention showed excellent thermal insulation performance, and has broad application prospects in the development of new energy-saving building materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0026] Figure 1 The suspending agent prepared in Example 1 of the present invention is in a colloidal state (a) and a dispersed suspension state (b).

[0027] Figure 2(a) is a cement sample prepared in Comparative Example 1 of the present invention; (b) is a cement sample prepared in Example 2. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] The invention provides a method for preparing a suspension agent, which comprises mixing a foaming agent with water, adding magnesium sulfate into the mixed solution, and fully stirring the solution to obtain the suspension agent.

[0030] The suspension prepared in this scheme exhibits excellent temperature responsiveness, can maintain a stable dispersed suspension state at room temperature, and transform into a colloidal state when the temperature drops below 20°C. The reversible conversion between these two states can be easily achieved through simple heating or cooling operations, which greatly facilitates the precise regulation of the material state in practical applications. In addition, the suspension can maintain a highly dispersed state of insoluble solid particles in water at room temperature, effectively preventing the agglomeration and rapid precipitation of the particles, and ensuring that the suspension remains uniform and stable for a long time.

[0031] Furthermore, the method further comprises the following steps: adding sodium chloride to the mixed solution after adding magnesium sulfate, wherein the amount of sodium chloride added is 5-7% of the mass of the mixed solution.

[0032] The addition of sodium chloride in this solution can increase the concentration of the solution, making the externally added suspending agent more stable and further optimizing the dispersing effect of the inorganic dispersant.

[0033] Furthermore, the mass ratio of the foaming agent to water is 1 to 2:1.

[0034] This solution optimizes the addition ratio of foaming agent to water, aiming to balance the foaming effect and the stability of the solution, ensuring that the foaming agent can fully exert its foaming potential in water while avoiding performance degradation caused by over-concentration or over-dilutement.

[0035] Furthermore, the amount of magnesium sulfate added is 30-40% of the mass of the mixed solution.

[0036] This solution optimizes the amount of magnesium sulfate added. As an important component of the suspension agent, precise control of its addition is crucial to improving the overall performance of the suspension agent. Within this range, magnesium sulfate can not only effectively promote the dispersion and stability of solid particles in the suspension system, but also have a positive impact on the rheology and storage stability of the suspension through its unique chemical properties.

[0037] Furthermore, the magnesium sulfate is added to the mixed solution in multiple times, and is quickly stirred for uniformity after each addition; more preferably, the magnesium sulfate is added to the mixed solution three times, with 45% of the magnesium sulfate added in the first addition, 30% in the second and third additions, and 25% in the third addition, respectively, and is quickly stirred for 1 minute after each addition.

[0038] In this scheme, the method of adding magnesium sulfate is adjusted and optimized. Specifically, magnesium sulfate is not added to the mixed solution all at once, but is added in batches and gradually. This strategy aims to effectively manage the heat released during the dissolution of magnesium sulfate and avoid the adverse effects of a large amount of heat release on the reaction system at one time, thereby ensuring the smooth progress of the suspension preparation process and safe operation.

[0039] More specifically, magnesium sulfate is added to the mixed solution three times. The first addition accounts for 45% of the total addition, followed by two additions of 30% and 25% respectively, to ensure that each addition can be quickly and evenly dispersed in the system. After each addition of magnesium sulfate, a quick stirring operation for 1 minute is immediately performed. This step is crucial to promote the rapid dissolution and uniform distribution of magnesium sulfate, and also helps to effectively dissipate heat and prevent the occurrence of local overheating.

[0040] Furthermore, the foaming agent is a plant protein foaming agent.

[0041] In this scheme, the type of foaming agent optimized is plant protein foaming agent, which shows obvious advantages in environmental protection, performance stability, foaming effect and economy, especially in the process of magnesium oxide dispersion and suspension, it shows better performance than other suspending agents.

[0042] Furthermore, the foaming power of the foaming agent is greater than 150 mL.

[0043] This solution optimizes the foaming power of the foaming agent, which is strictly defined in accordance with the national standard "GB / T7462 Method for Determining Foaming Power of Surfactants". When the foaming power of the foaming agent reaches and exceeds 150mL, it can more effectively promote the uniform dispersion of insoluble solid particles in the solvent system under the action of the suspending agent. This optimization not only improves the dispersion effect, but also ensures that the dispersion system has good light transmittance and stability.

[0044] The present invention also provides a method for applying a suspending agent in magnesium oxide modified cement, which is characterized by comprising the following steps:

[0045] S1: Preparation of intermediate solution: adding magnesium oxide to the suspending agent at a mass ratio of 1:1-2 and stirring evenly, and maintaining for 24-48 hours to obtain an intermediate solution;

[0046] S2: Preparation of magnesium oxide suspension, adding the intermediate solution into the dispersion solvent at a volume ratio of 1:1 to 10 and stirring evenly to obtain a colloidal fluid liquid, namely, magnesium oxide suspension;

[0047] S3: adding magnesium oxide externally, adding the magnesium oxide suspension into the cement mixing process.

[0048] The use of a suspending agent in this solution enables the magnesium oxide particles to be highly evenly distributed in the cement matrix, thereby improving the overall homogeneity of the cement material as well as its mechanical properties, durability and working performance. This improvement not only maintains the basic properties of cement, but also significantly reduces the weight of the cement sample, helps reduce the cost of raw materials, improves production efficiency, and significantly reduces carbon emissions during cement production. In particular, in the heat transfer effect test, the cement sample prepared by adding magnesium oxide using the method of the present invention exhibits excellent thermal insulation performance, and has broad application prospects in the development of new energy-saving building materials.

[0049] Furthermore, the dispersing solvent is water or 5-7% sodium chloride solution.

[0050] The dispersing solvent used in this scheme is water or sodium chloride solution, wherein the sodium chloride solution can make the added external suspending agent disperse more stably, improve the dispersion effect, and can also prolong the suspension time of the product to be dispersed in the solution, so that the dispersion state can be maintained longer.

[0051] Furthermore, the amount of magnesium oxide added is 5% to 10% of the mass of cement.

[0052] This solution defines the optimal range of magnesium oxide addition, aiming to maximize the balance and improvement of the comprehensive properties of cement, including but not limited to mechanical strength, durability and significant thermal insulation properties introduced by magnesium oxide.

[0053] Specifically, when the amount of magnesium oxide added is in this optimized range, it can effectively play its mechanism of action: the appropriate amount of magnesium oxide can react with the components in the cement matrix to form stable hydration products, which not only enhance the microstructure of the cement matrix, but also improve the density and impermeability of concrete by filling pores and refining the pore structure, thereby significantly enhancing its durability. At the same time, the specific thermal properties of magnesium oxide are fully demonstrated within this dosage range, bringing additional thermal insulation effects to cement-based materials.

[0054] If the amount of magnesium oxide added is too low, the expected performance improvement effect such as heat resistance will not be fully achieved due to insufficient addition, resulting in limited modification benefits. On the contrary, if the amount added is too much, the volume expansion characteristics of magnesium oxide will gradually appear, causing adverse effects on the internal structure of the cement matrix, such as reducing compressive strength and increasing the risk of cracking, thereby weakening the overall project quality and safety.

[0055] Example 1

[0056] Preparation of suspension

[0057] Weigh 100g of a vegetable protein foaming agent with a foaming power of more than 150mL (determined according to GB / T 7462), and mix it with 100g of water. Weigh 70g of magnesium sulfate and add it to the mixed solution three times, with the amount added each time being 31.5g, 21.0g and 17.5g respectively. After each addition of magnesium sulfate, stir it clockwise for 1min with a stirring rod to gradually transform the foaming agent and water from a fluid state to a colloidal state. A large amount of heat will be released during the process to obtain a colloidal suspension. Place it in an environment below 20°C, and the suspension will gradually transform into a colloidal state and then be stored for later use.

[0058] Example 2

[0059] Application of suspending agent in magnesium oxide modified cement, external magnesium oxide suspension

[0060] Preparation of intermediate solution: Add 20 g of magnesium oxide powder to 20 g of the suspension prepared in Example 1, stir evenly, and keep for 24 hours to obtain an intermediate solution.

[0061] Preparation of magnesium oxide suspension: Add the intermediate liquid into 40g of 6% NaCl aqueous solution, stir quickly and evenly to obtain a colloidal liquid, which is the magnesium oxide suspension.

[0062] Adding magnesium oxide suspension: Add magnesium oxide suspension into 380g cement for mixing, and adjust the water-cement ratio to 0.4 with water. At this time, the addition ratio of magnesium oxide is 5%.

[0063] Example 3

[0064] Application of suspending agent in magnesium oxide modified cement, external magnesium oxide suspension

[0065] Preparation of intermediate solution: 40 g of magnesium oxide powder was added to 40 g of the suspension prepared in Example 1, stirred evenly, and maintained for 24 hours to obtain an intermediate solution.

[0066] Preparation of magnesium oxide suspension: Add the intermediate liquid into 80g of 6% NaCl aqueous solution, stir quickly and evenly to obtain a colloidal liquid, which is the magnesium oxide suspension.

[0067] Adding magnesium oxide suspension: Add magnesium oxide suspension into 360g cement for mixing, and adjust the water-cement ratio to 0.4 with water. At this time, the addition ratio of magnesium oxide is 10%.

[0068] Comparative Example 1

[0069] The blank control group was not doped with magnesium oxide.

[0070] 400g of cement was mixed with water at a water-cement ratio of 0.4, and the addition ratio of magnesium oxide was 0%.

[0071] Comparative Example 2

[0072] Control group, external magnesium oxide water suspension

[0073] Preparation of magnesium oxide aqueous suspension: Add 20 g of magnesium oxide powder into 40 g of water and stir evenly to obtain magnesium oxide aqueous suspension.

[0074] Addition of magnesium oxide aqueous suspension: Stir the magnesium oxide aqueous suspension evenly and add it into 380g cement paste with a water-cement ratio of 0.4. At this time, the addition ratio of magnesium oxide is 5%.

[0075] Comparative Example 3

[0076] Control group, suspension without magnesium oxide

[0077] Preparation of a suspension free of magnesium oxide: Add 20 g of the suspension prepared in Example 1 to 40 g of a 6% NaCl aqueous solution, and stir rapidly to obtain a colloidal fluid liquid, which is a suspension free of magnesium oxide;

[0078] No magnesium oxide suspension is added: magnesium oxide suspension is added into 380g cement paste with a water-cement ratio of 0.4. At this time, the addition ratio of magnesium oxide is 0%.

[0079] The specific experimental conditions of each embodiment are shown in Table 1:

[0080] Table 1 List of experimental conditions corresponding to each embodiment

[0081] Sample No. Cement modified admixtures Magnesium oxide addition% Sample size Water-cement ratio Comparative Example 1 / 0 40mm×40mm×40mm 0.4 Comparative Example 2 Magnesium oxide aqueous suspension 5 40mm×40mm×40mm 0.4 Comparative Example 3 Suspension without magnesium oxide 0 40mm×40mm×40mm 0.4 Example 2 Magnesium oxide suspension 5 40mm×40mm×40mm 0.4 Example 3 Magnesium oxide suspension 10 40mm×40mm×40mm 0.4

[0082] Test results and analysis

[0083] (1) Performance and Effect of the Suspension Prepared in Example 1

[0084] like Figure 1 As shown, the state of the suspension prepared in Example 1 at room temperature is Figure 1 b shows the dispersed suspension state, while below 20℃ Figure 1 The colloidal state shown in a can be converted into each other by heating and cooling. This transformation not only reflects the sensitivity of the suspending agent to temperature changes, but also reveals the adjustment of its internal structure - the interaction between particles is enhanced, forming a tighter network structure, thereby restricting the free movement of particles, resulting in reduced fluidity of the system and presenting a gel-like physical state. What is particularly important is that the conversion between this colloidal state and the dispersed suspension state is reversible and can be achieved by simple heating or cooling operations, which provides great flexibility for regulating the state of the material according to needs in practical applications.

[0085] In contrast, magnesium oxide powder is directly added to water. Due to the strong interaction between particles and the large specific surface area, magnesium oxide powder without special treatment is very easy to agglomerate and precipitate quickly in water, resulting in uneven light transmittance of the solution, and almost all of it is precipitated at the bottom of the container after standing for a while. This not only limits the scope of application of magnesium oxide, but also affects its performance as a functional material; the suspending agent prepared using Example 1 successfully overcomes the above problems, and magnesium oxide is expanded and dispersed under its action, and the prepared magnesium oxide suspension shows good optical transmittance, and light can pass evenly without significant scattering or blocking, which reflects the uniformity of particle dispersion and the stability of the system. Because the internal magnesium oxide particles achieve highly uniform dispersion, not only the agglomeration and precipitation of particles are avoided, but also the stability and optical consistency of the suspension for a long time (at least more than 24 hours) are guaranteed.

[0086] (2) Comparison of the morphology and weight of cement samples prepared in Example 2 and Comparative Example 1

[0087] In the comparative test, Example 2 used 5% magnesium oxide as a cement admixture and was systematically evaluated with Comparative Example 1 without any substitution. Figure 2 a and Figure 2As shown in Figure b, the comparison results show that the magnesium oxide modified cement sample prepared in Example 2 forms a porous structure composed of magnesium oxide and other materials, and the pores and interfaces inside it will significantly increase the thermal resistance, thereby reducing the overall thermal conductivity and playing a heat-resistant effect; in addition, the volume expansion effect of magnesium hydroxide generated during the hydration of magnesium oxide effectively compensates for the common shrinkage problem of cement paste. More importantly, since the magnesium oxide external addition process in Example 2 uses the suspending agent prepared by the present invention, its uniform dispersion further amplifies the above-mentioned enhancement effect.

[0088] After the same pouring, curing and drying treatment, the quality difference between the two is obvious. Specifically, the mass of the cement sample in Example 2 is 77.1307g, which is much lower than 119.1374g in Comparative Example 1. This result directly shows that the method of adding magnesium oxide to cement modification in the present invention not only maintains the basic properties of the cement sample, but also significantly improves its physical and mechanical performance indicators such as crack resistance and shrinkage rate and durability, while effectively reducing the amount of cement used, thereby reducing the cost of raw materials and improving production efficiency.

[0089] In addition, cement production is a high-energy consumption and high-emission process, and about 0.8 tons of carbon dioxide are produced for every ton of cement produced. According to the results of this experiment, when preparing cement of similar volume or function, the external admixture method of the present invention saves about 38.5% of cement usage. This means that in larger-scale production, the consumption of cement can be significantly reduced, thereby reducing carbon dioxide emissions.

[0090] (3) Comparison of Density Uniformity of Cement Samples Prepared in Example 2 and Comparative Example 2

[0091] The test was conducted by randomly selecting positions on the cement samples prepared in Example 2 and Comparative Example 2 and accurately cutting out small samples of the same volume, and weighing the samples using an electronic balance with an accuracy of 0.0001 grams. The results showed that the masses of the cement samples prepared in Comparative Example 2 were 10.3502 g and 11.0452 g, respectively, and the mass difference between the two was significant, reaching 6.71%. This significant difference may reflect the inhomogeneity of the internal composition or structure of the sample, which has a potential impact on the overall performance of the cement.

[0092] In contrast, the cement samples prepared in Example 2 were cut out under the same conditions, and their masses were 10.4012g and 10.4677g respectively, and the mass difference between the two was very small, only 0.64%, which supported the effectiveness of the suspending agent in the present invention. The suspending agent can significantly promote the highly uniform dispersion of magnesium oxide in the suspension, and then in the cement modification process, when used as an admixture, it can ensure that magnesium oxide is highly uniformly distributed in the cement matrix.

[0093] (4) Comparison of heat transfer effects of cement samples prepared in various embodiments and comparative examples

[0094] Heat transfer test: The test simulated the heat transfer process of cement samples at room temperature. A uniform standard heating surface was used to ensure that the heating surface temperature gradually decreased from 34.4°C to 26.4°C and finally stabilized at 25.8°C to simulate the complexity of temperature changes in the actual use environment. To ensure the fairness of the experimental results, all test samples were heated under the same heating contact surface area to reduce the interference of external conditions on the heat transfer performance. The experiment set five key timing points within 0 to 160 minutes, and accurately measured and recorded the surface temperature of the heating surface of each cement sample at each time point. The detailed time interval setting aims to fully capture the subtle changes in the heat transfer process, so as to more accurately evaluate the effect of magnesium oxide on the heat transfer performance of cement under different incorporation methods.

[0095] Table 2 Sample heat transfer record

[0096]

[0097] As shown in the test data of Table 2, compared with Comparative Example 1 (pure cement sample), Comparative Example 2 (adding magnesium oxide in the form of magnesium oxide aqueous suspension) and Comparative Example 3 (adding a suspension without magnesium oxide) did not show significant differences in the test temperatures at the five timing points. This result shows that simply adding magnesium oxide in the form of an aqueous suspension cannot effectively improve the thermal insulation performance of cement if the magnesium oxide particles are not evenly distributed in the cement matrix.

[0098] However, Example 2 (using the magnesium oxide suspension prepared by the suspension agent of the present invention and cement) showed a completely different effect. The test lasted only 33 minutes at the first timing point, and the measured temperature was significantly different from that of the other three samples, and the average temperature difference was maintained at about 1°C during the entire test period, which directly proved that the method of the present invention can significantly improve the thermal insulation performance of cement.

[0099] The cement sample prepared by this method significantly improves the thermal insulation performance while maintaining the original performance, providing a solution for new energy-saving building materials in the field of civil engineering, and is particularly suitable for wall structures with high requirements for thermal insulation performance, which helps to reduce heat energy loss and achieve low-carbon environmental protection. The core of the present invention is to use a suspending agent to achieve a highly uniform dispersion of magnesium oxide particles in the cement matrix, which not only overcomes the disadvantage of uneven distribution of magnesium oxide under the traditional external admixture method, but also effectively improves the heat transfer performance control ability of cement paste by optimizing the particle distribution structure, thereby enhancing its thermal insulation effect.

[0100] In summary, the suspension prepared by the present invention exhibits excellent temperature response performance, can maintain a stable dispersed suspension state at room temperature, and transform into a colloidal state when the temperature drops below 20°C. The conversion between these two states can be easily achieved through simple heating or cooling operations, which greatly facilitates the precise regulation of the material state in practical applications. In addition, the suspension significantly optimizes the dispersion effect of magnesium oxide particles in water, effectively avoids the performance limitation of traditional magnesium oxide powder caused by agglomeration and rapid precipitation, and ensures that the suspension has long-term optical transmittance and stability.

[0101] In the application of cement modification, the use of the suspending agent enables the magnesium oxide particles to be highly evenly distributed in the cement matrix, while maintaining the basic properties of cement, and also significantly reducing the weight of the cement sample, which helps to reduce the cost of raw materials, improve production efficiency, and significantly reduce carbon emissions in the cement production process. In particular, in the heat transfer effect test, the cement sample prepared by adding magnesium oxide using the method of the present invention showed excellent thermal insulation performance, and has broad application prospects in the development of new energy-saving building materials.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a suspension concentrate, characterized in that: Mix the foaming agent with water, add magnesium sulfate into the mixed solution, stir thoroughly to make the mixture uniform, and obtain a suspension.

2. The method for preparing a suspension concentrate according to claim 1, wherein: The following steps are also included: After adding magnesium sulfate, sodium chloride is added to the mixed solution, and the amount of sodium chloride added is 5-7% of the mass of the mixed solution.

3. The method for preparing a suspension concentrate according to claim 1, characterized in that: The mass ratio of the foaming agent to water is 1 to 2:

1.

4. The method for preparing a suspension concentrate according to claim 1, characterized in that: The amount of magnesium sulfate added is 30-40% of the mass of the mixed solution.

5. The method for preparing a suspension concentrate according to claim 1, characterized in that: The magnesium sulfate is added to the mixed solution in multiple times, and is quickly stirred for uniformity after each addition; more preferably, the magnesium sulfate is added to the mixed solution three times, and the adding method is 45% of the magnesium sulfate addition amount is added in the first time, 30% in the second time, and 25% in the third time, respectively, and is quickly stirred for 1 minute after each addition.

6. The method for preparing a suspension concentrate according to claim 1, characterized in that: The foaming agent is a vegetable protein foaming agent.

7. The method for preparing a suspension concentrate according to claim 1, characterized in that: The foaming power of the foaming agent is greater than 150 mL.

8. The method for using the suspending agent in magnesium oxide modified cement according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1: Preparation of intermediate solution: adding magnesium oxide into the suspending agent at a mass ratio of 1:1-2 and stirring evenly, and maintaining for 24-48 hours to obtain an intermediate solution. S2: Preparation of magnesium oxide suspension, adding the intermediate solution into the dispersion solvent at a volume ratio of 1:1 to 10 and stirring evenly to obtain a colloidal fluid liquid, namely, magnesium oxide suspension; S3: adding magnesium oxide externally, adding the magnesium oxide suspension into the cement mixing process.

9. The method for applying the suspending agent in magnesium oxide modified cement according to claim 8, characterized in that: The dispersing solvent is water or 5-7% sodium chloride solution.

10. The method for applying the suspending agent according to claim 9 in magnesium oxide modified cement, characterized in that: The added amount of magnesium oxide is 5-10% of the cement mass.

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