Preparation method of light-weight thermal insulation cement aerogel material and application thereof

Abstract

The application belongs to the technical field of material engineering, and more particularly relates to a preparation method of light heat-insulating cement aerogel material and application thereof, wherein the preparation method comprises the following steps: dissolving a binder in water, then cooling the solution to room temperature; adding a dispersing agent into the solution, then adding cement, stirring uniformly, adding a hydrophobic component, and stirring uniformly; adding reinforcing fibers, stirring uniformly, wherein the reinforcing fibers are at least one of polymer fibers, carbon fibers and glass fibers; adding a foaming component, and stirring uniformly; pouring the solution into a mold, using liquid nitrogen to freeze and form pores, and restoring to room temperature after completion; then drying, and obtaining the cement aerogel material after completion of the drying. The cement aerogel material prepared by the application has excellent properties such as high strength, light weight and non-flammability, and can be used as a buffer layer of an explosion-proof box to improve the performance of the explosion-proof box as a whole.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material engineering, more particularly, it relates to a preparation method of light thermal insulation cement aerogel material and application thereof. BACKGROUND

[0002] In the complex system of modern industry, explosion-proof boxes occupy a pivotal position and are widely distributed in many key industries such as petroleum and chemical industry, coal mining, pharmaceutical industry, and power industry. The petroleum and chemical industry is full of flammable gases and liquids, such as gasoline vapor in oil refineries and various flammable and explosive chemicals in chemical plants; the coal mine is always filled with gas, which is a highly dangerous flammable gas; the pharmaceutical factory often has volatile organic solvents, and the combustible mixture formed after volatilization is everywhere; and the power system may also have combustible dust environment due to dust accumulation. In such a high-risk environment, the explosion-proof box acts as a solid safety barrier to protect the internal electrical equipment, precision instruments and other equipment, avoid the contact between the internal electrical element faults, such as electric spark and electric arc, or high temperature caused by current overload, and the external flammable and explosive substances, thereby preventing the occurrence of catastrophic explosion accidents, and also maximizing the resistance to shock wave and high temperature radiation when the explosion occurs outside to ensure the relative safety of the equipment in the box.

[0003] However, with the rapid progress of industrial production technology and the continuous strictness of safety production standards, explosion-proof boxes are facing unprecedented performance challenges, and the thermal insulation performance is the core concern. In many actual industrial scenes, explosion-proof boxes are often placed in high-temperature harsh environments. For example, in the core production area of the oil refinery, the ambient temperature around various high-temperature reaction devices is high all year round, and the continuous high-temperature heat radiation is like an invisible killer, which threatens the normal operation of the explosion-proof box and its internal equipment at any time. For another example, when a fire or other unexpected disaster occurs, the explosion-proof box becomes the direct target of the high-temperature flame, and must withstand the high-temperature roasting of the external flame of thousands of degrees Celsius in a short time.

[0004] Looking back at the traditional thermal insulation materials of explosion-proof boxes, such as common glass fiber cotton and rock wool, they have played a certain role in thermal insulation in the past period of time, but their defects are exposed under today's high standards. The thermal insulation efficiency of these traditional materials is relatively low, and it is difficult to build a solid and reliable thermal resistance line under long-term high-temperature attack. Taking a chemical production workshop as an example, in a continuous high-temperature operating environment, the internal temperature of the explosion-proof box using traditional thermal insulation materials will gradually rise over time, and eventually may exceed the temperature threshold allowed for the normal operation of the equipment in the box, causing the equipment to malfunction due to overheating, and then triggering a series of chain reactions, such as electric spark caused by electrical short circuit, which is undoubtedly a major hidden danger of explosion in the explosion-proof area.

[0005] Moreover, the physical properties of traditional thermal insulation materials also bring many inconveniences to the application of explosion-proof boxes. Their density is generally large, which significantly increases the overall weight of the explosion-proof box. In some special application scenarios, such as offshore oil drilling platforms, space is limited and the stability and weight control of the equipment are extremely high, and the heavy explosion-proof box will affect the overall structural balance and safety of the platform; in high-altitude operation equipment, heavy explosion-proof boxes will increase the load of the equipment, reduce operation efficiency and increase safety risks.

[0006] More seriously, when traditional thermal insulation materials encounter extremely high temperatures or direct flame impact, they often undergo a series of undesirable physical or chemical changes. Shrinkage deformation may occur, causing gaps in the thermal insulation layer and allowing large amounts of heat to enter; or melting may occur, causing the thermal insulation function to be lost instantly; or even harmful gases may be released, which not only corrode the equipment inside the box and reduce its service life, but also mix with external flammable materials when an explosion occurs, further exacerbating the power and harm range of the explosion.

[0007] In summary, in the face of increasingly complex industrial production environments and rising safety needs, as well as the backdrop of the booming development of new material technology, it is imperative to develop new explosion-proof box thermal insulation materials with excellent thermal insulation efficiency, lightweight, excellent high-temperature stability, and green environmental protection. This is an important research topic in the field of industrial safety that needs to be tackled, which has immeasurable significance for ensuring the stability, safety, and sustainable development of industrial production. SUMMARY

[0008] The present application provides a preparation method of a lightweight thermal insulation cement aerogel material and its application. The cement aerogel material prepared by the present application has excellent properties such as high strength, light weight, and non-flammability, and can improve the performance of the explosion-proof box as a buffer layer.

[0009] In a first aspect, the present application provides a preparation method of a lightweight thermal insulation cement aerogel material, which adopts the following technical solution:

[0010] A preparation method of a lightweight thermal insulation cement aerogel material, comprising the following steps:

[0011] S1: Dissolve the binder in water, and the mass ratio of the binder to water is (0.4-0.6):(14-18), then cool the solution to room temperature;

[0012] S2: Add a dispersing agent to the solution of S1, then add cement, and stir uniformly, the mass ratio of cement to water is (1-1.25):(14-18);

[0013] S3: Add a hydrophobic component and stir uniformly;

[0014] S4: adding reinforcing fibers, stirring evenly, the reinforcing fibers being at least one of polymer fibers, carbon fibers and glass fibers, the reinforcing fibers having a length of 10-20 mm and a diameter of 10-15 μm, the mass ratio of the reinforcing fibers to the cement being 0.2: (1-1.25);

[0015] S5: adding a foaming component, stirring evenly;

[0016] S6: pouring the solution of S5 into a mold, using liquid nitrogen to freeze-pore, and returning to room temperature after the freeze-pore is completed;

[0017] S7: placing the mold and the product after the freeze-pore of S6 into an oven to dry, and obtaining the cement aerogel material after the drying is completed.

[0018] Further, the adhesive includes at least one of agarose, sodium alginate, chitosan, hyaluronic acid, polyacrylic acid derivative, sodium polyacrylate, polyethylene glycol, polyacrylamide and polyurethane.

[0019] Further, in the step S2, the cement is added in at least two times.

[0020] Further, the dispersant includes at least one of sulfonate water reducer, naphthalene water reducer and polycarboxylic acid water reducer, and the mass ratio of the dispersant to the cement is 0.03: (1-1.25).

[0021] Further, the cement is sulphoaluminate cement or a mixture of sulphoaluminate cement and Portland cement.

[0022] Further, the hydrophobic component includes at least one of trimethoxysilane and triethoxysilane, and the mass ratio of the hydrophobic component to the cement is 0.12: (1-1.25).

[0023] Further, the foaming component is one of hydrogen peroxide, sodium bicarbonate, ammonium carbonate and ammonium bicarbonate, and the mass ratio of the foaming component to the cement is 0.5: (1-1.25).

[0024] Further, in the step S6, the freeze-pore is directional freezing, the freezing temperature is -120 to -180 ℃, and the time is 30-60 min.

[0025] Further, in the step S7, the drying temperature is 50-80 ℃.

[0026] In a second aspect, the application provides an application of the lightweight thermal insulation cement aerogel material, and adopts the following technical scheme:

[0027] The application relates to an application of a light-weight heat-insulating cement aerogel material to a heat-insulating material of an explosion-proof box.

[0028] In summary, the application has the following beneficial effects:

[0029] The application adopts fast-hardening cement as a framework to ensure the strength of the whole material, so that the structure is not easily damaged when subjected to external force impact. In addition, the cement has chemical inertness, corrosion resistance, combustion resistance, and penetration resistance, and can be used as a good protective material. However, the water-binder ratio of general cement materials is too low, although the strength can be ensured, the density is relatively high, and the light-weight requirement cannot be met. Therefore, the application adopts a higher water-binder ratio to meet the light-weight requirement of the aerogel material, and in order to avoid the problem of strength reduction caused by the too high water-binder ratio, the application further adds reinforcing fibers.

[0030] In terms of light-weight requirement, the application increases the water-binder ratio of the material, and combines pore-forming by a foaming agent and pore-forming by directional freezing technology to improve the porosity of the material and reduce the total mass. Compared with conventional explosion-proof boxes which are generally heavy and not easy to carry, the application can make the explosion-proof box convenient to carry and transport.

[0031] In terms of strength requirement, the application adds reinforcing fibers, but the use of reinforcing fibers often has the problem of uneven dispersion, which may reduce the material performance and affect the foaming of the aerogel itself. Therefore, the application optimizes the size parameters of the reinforcing fibers, and further adds an adhesive to uniformly disperse the reinforcing fibers and not affect the pore-forming by the foaming component and the pore-forming by directional freezing, so that the pore structure of the application is uniform and ordered, the density is further reduced, and the strength of the material is further improved.

[0032] Finally, the preparation method of the application has the advantages of low cost, simplicity and environmental protection. The raw materials are widely available and easy to obtain, which reduces the production cost. At the same time, the whole preparation process is safe and environmentally friendly, in line with the concept of sustainable development. The preparation process is simple and easy to control, which is conducive to large-scale industrial production, thereby promoting the wide application of the technology in the field of construction. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 Picture of the sample obtained in Example 1.

[0034] Figure 2 Compressive strength curve of the sample obtained in Example 1.

[0035] Figure 3 Microstructure diagram of the sample obtained in Example 1. DETAILED DESCRIPTION

[0036] The application will be further described in detail below in combination with the drawings and examples.

[0037] The application first provides a preparation method of a light thermal insulation cement aerogel material, comprising the following steps:

[0038] S1: Dissolve the binder in water, the mass ratio of the binder to water is (0.4-0.6):(14-18), and then cool the solution to room temperature;

[0039] S2: Add a dispersing agent to the solution of S1, and then add cement, the cement is added at least twice, and stir uniformly, the mass ratio of the cement to water is (1-1.25):(14-18);

[0040] S3: Add a hydrophobic component and stir uniformly;

[0041] S4: Add a reinforcing fiber, stir uniformly, the reinforcing fiber is at least one of a polymeric fiber, a carbon fiber and a glass fiber, the length of the reinforcing fiber is 10-20 mm, the diameter of the reinforcing fiber is 10-15 μm, and the mass ratio of the reinforcing fiber to cement is 0.2:(1-1.25); the polymeric fiber can be one of a polypropylene fiber, a polyethylene fiber, a polystyrene fiber, a polyester fiber, a polyamide fiber and a polyvinyl alcohol fiber, and the molecular weight of the polymer is 300-500.

[0042] S5: Add a foaming component and stir uniformly;

[0043] S6: Pour the solution of S5 into a mold, use liquid nitrogen to freeze and form pores, the freezing and pore forming is directional freezing, the freezing temperature is -120--180℃, the time is 30-60 min, and after the freezing and pore forming is completed, the mold and the product are taken out and restored to room temperature;

[0044] S7: Put the mold and the product after the freezing and pore forming of S6 into an oven to dry, the temperature is 50-80℃, and after the drying is completed, the cement aerogel material is obtained.

[0045] Further, the binder comprises at least one of agarose, sodium alginate, chitosan, hyaluronic acid, a polyacrylic acid derivative, sodium polyacrylate, polyethylene glycol, polyacrylamide and polyurethane.

[0046] Further, the dispersing agent comprises at least one of a sulfonate water reducing agent, a naphthalene water reducing agent and a polycarboxylic acid water reducing agent, and the mass ratio of the dispersing agent to cement is 0.03:(1-1.25).

[0047] Further, the cement is sulphoaluminate cement or a mixture of sulphoaluminate cement and Portland cement. Specifically, in the embodiments of the present application, the sulphoaluminate cement is sulphoaluminate white cement Polar Bear 62.5 grade, and the Portland cement is Portland (Hulin 62.5) cement

[0048] Further, the hydrophobic component includes at least one of trimethoxysilane and triethoxysilane, and the mass ratio of the hydrophobic component to the cement is 0.12:(1-1.25).

[0049] Further, the foaming component is one of hydrogen peroxide, sodium bicarbonate, ammonium carbonate, and ammonium bicarbonate, and the mass ratio of the foaming component to the cement is 0.5:(1-1.25).

[0050] The cement aerogel material prepared as described above can be used as a heat insulation material for an explosion-proof box.

[0051] The following is described by specific embodiments.

[0052] Embodiment 1

[0053] S1, 0.48 parts of polyethylene glycol 400 were weighed and dissolved in 14 parts of water, and the solution was restored to room temperature.

[0054] S2, 0.03 parts of Suobote polycarboxylic acid water reducer 801 were added, and then 0.5 parts of sulphoaluminate white cement Polar Bear 62.5 grade were slowly added, the stirring time was 30 min, and the stirring speed was 500 r / min. Then 0.5 parts of sulphoaluminate white cement were slowly added, and the stirring was continued.

[0055] S3, 0.12 parts of hydrophobic component methyltrimethylsilane were added, and stirred for 30 minutes.

[0056] S4, 0.2 parts of glass fiber were added, and stirred for 30 minutes.

[0057] S5, 0.5 parts of foaming component hydrogen peroxide were added, and stirred for 1 minute.

[0058] S6, the solution was immediately poured into a prepared mold, and liquid nitrogen was used to freeze pore forming at-150℃ for 45 minutes. After freezing, the solution was thawed and restored to room temperature.

[0059] S7, after being restored to room temperature, the mold was placed in an oven for drying, the oven temperature was set to 80°, and after the drying was completed, the cement aerogel material sample S1 was obtained.

[0060] Embodiment 2

[0061] S1, 0.48 parts of polyacrylic acid sodium (molecular weight 2100) were weighed and dissolved in 14 parts of water, and the solution was restored to room temperature.

[0062] S2, add 0.03 parts of polycarboxylic acid water reducer Subote 801, then slowly add 0.625 parts of cement, the cement is a mixture of sulphoaluminate cement and portland cement (Hulin 62.5) with a mass ratio of 1:1, the stirring time is 30 min, and the stirring speed is 500 r / min. Slowly add 0.625 parts of the above cement again, and continue to stir.

[0063] S3, add 0.12 parts of hydrophobic component, and stir for 30 minutes.

[0064] S4, add 0.2 parts of glass fiber, and stir for 30 minutes.

[0065] S5, add 0.5 parts of foaming component hydrogen peroxide, and stir for 1 minute.

[0066] S6, immediately pour the solution into a prepared mold, use liquid nitrogen to freeze pore forming at -150 DEG C for 60 minutes. After freezing, thaw and recover to room temperature.

[0067] S7, after recovering to room temperature, put the mold into an oven for drying, and the oven temperature is set to 80 DEG C. After drying, the cement aerogel material sample S2 is obtained.

[0068] Example 3

[0069] S1, weigh 0.48 parts of sodium alginate into 14 parts of water, and recover the solution to room temperature.

[0070] S2, add 0.03 parts of naphthalene water reducer Subote (SBT-JM-A), then slowly add 0.625 parts of sulphoaluminate cement, the stirring time is 30 min, and the stirring speed is ~ 500 r / min. Slowly add 0.625 parts of sulphoaluminate cement again, and continue to stir.

[0071] S3, add 0.12 parts of hydrophobic component methyltrimethylsilane, and stir for 30 minutes.

[0072] S4, add 0.2 parts of glass fiber, and stir for 30 minutes.

[0073] S5, add 0.5 parts of foaming component hydrogen peroxide, and stir for 1 minute.

[0074] S6, immediately pour the solution into a prepared mold, use liquid nitrogen to freeze pore forming at -150 DEG C for 30 minutes. After freezing, thaw and recover to room temperature.

[0075] S7, after recovering to room temperature, put the mold into an oven for drying, and the oven temperature is set to 80 DEG C. After drying, the cement aerogel material sample S3 is obtained.

[0076] Example 4

[0077] S1, 0.48 parts of polyacrylamide (molecular weight 5 million) was weighed into 14 parts of water, and the solution was brought to room temperature.

[0078] S2, 0.03 parts of naphthalene-based water reducer Sobot (SBT-JM-A) was added, and then 0.625 parts of sulphoaluminate cement was slowly added, the stirring time was 30 min, and the stirring speed was ~ 500 r / min. 0.625 parts of sulphoaluminate cement was slowly added, and the stirring was continued.

[0079] S3, 0.12 parts of hydrophobic component methyltrimethylsilane was added, and stirred for 30 minutes.

[0080] S4, 0.2 parts of glass fiber was added, and stirred for 30 minutes.

[0081] S5, 0.5 parts of foaming component hydrogen peroxide was added, and stirred for 1 minute.

[0082] S6, immediately pour the solution into the prepared mold, use liquid nitrogen to freeze pore at -150℃ for 45 minutes. After freezing, thaw and restore to room temperature.

[0083] S7, after restoring to room temperature, the whole mold was put into an oven for drying, the oven temperature was set to 80°. After drying, the cement aerogel material sample S4 was obtained.

[0084] Example 5

[0085] S1, 0.6 parts of polyethylene glycol 400 was weighed into 14 parts of water, and the solution was brought to room temperature.

[0086] S2, 0.03 parts of naphthalene-based water reducer Sobot (SBT-JM-A) was added, and then 0.5 parts of sulphoaluminate cement was slowly added, the stirring time was 30 min, and the stirring speed was ~ 500 r / min. 0.5 parts of sulphoaluminate cement was slowly added, and the stirring was continued.

[0087] S3, 0.12 parts of hydrophobic component methyltrimethylsilane was added, and stirred for 30 minutes.

[0088] S4, 0.2 parts of glass fiber was added, and stirred for 30 minutes.

[0089] S5, 0.5 parts of foaming component hydrogen peroxide was added, and stirred for 1 minute

[0090] S6, immediately pour the solution into the prepared mold, use liquid nitrogen to freeze pore at -150℃ for 45 minutes. After freezing, thaw and restore to room temperature.

[0091] S7, after recovering to room temperature, the whole mold is put into the oven for drying, and the oven temperature is set to 80°. After drying is completed, the cement aerogel material sample S5 can be obtained.

[0092] Example 6

[0093] S1, 0.6 parts of polyethylene glycol 400 is weighed and dissolved in 18 parts of water, and the solution is recovered to room temperature.

[0094] S2, 0.03 parts of naphthalene water reducer Sobot (SBT-JM-A) is added, and then 0.5 parts of sulphoaluminate cement is slowly added, the stirring time is 30 min, and the stirring speed is ~ 500 r / min. Then 0.5 parts of sulphoaluminate cement is slowly added, and the stirring is continued.

[0095] S3, 0.12 parts of hydrophobic component methyltrimethylsilane is added, and stirred for 30 minutes.

[0096] S4, 0.2 parts of glass fiber is added, and stirred for 30 minutes.

[0097] S5, 0.5 parts of foaming component hydrogen peroxide is added, and stirred for 1 minute.

[0098] S6, immediately pour the solution into the prepared mold, use liquid nitrogen to freeze pore forming at-150℃ for 45 minutes. After freezing is completed, thawing is recovered to room temperature.

[0099] S7, after recovering to room temperature, the whole mold is put into the oven for drying, and the oven temperature is set to 80°. After drying is completed, the cement aerogel material sample S5 can be obtained.

[0100] Example 7

[0101] S1, 0.48 parts of polyethylene glycol 400 is weighed and dissolved in 14 parts of water, and the solution is recovered to room temperature.

[0102] S2, 0.03 parts of Sobot polycarboxylic acid water reducer 801 is added, and then 0.5 parts of sulphoaluminate white cement polar bear 62.5 grade is slowly added, the stirring time is 30 min, and the stirring speed is 500 r / min. Then 0.5 parts of sulphoaluminate white cement is slowly added, and the stirring is continued.

[0103] S3, 0.12 parts of hydrophobic component methyltrimethylsilane is added, and stirred for 30 minutes.

[0104] S4, 0.2 parts of carbon fiber is added, and stirred for 30 minutes.

[0105] S5, 0.5 parts of foaming component hydrogen peroxide is added, and stirred for 1 minute.

[0106] S6, immediately pour the solution into the prepared mold, use liquid nitrogen to freeze pore at -180℃ for 30 minutes. After freezing is completed, thaw to room temperature.

[0107] S7, after recovering to room temperature, put the mold as a whole into an oven for drying, the oven temperature is set to 80°, after drying is completed, the cement aerogel material sample S7 can be obtained.

[0108] Example 8

[0109] S1, weigh 0.48 parts of polyethylene glycol 400 into 14 parts of water, and recover the solution to room temperature.

[0110] S2, add 0.03 parts of Sobotec polycarboxylic acid water reducer 801, then slowly add 0.5 parts of sulphoaluminate white cement polar bear 62.5 grade, the stirring time is 30 min and the stirring speed is 500 r / min. Then slowly add 0.5 parts of sulphoaluminate white cement and continue stirring.

[0111] S3, add 0.12 parts of hydrophobic component methyltrimethylsilane and stir for 30 minutes.

[0112] S4, add 0.2 parts of polypropylene fiber with a molecular weight of 300-500 and stir for 30 minutes.

[0113] S5, add 0.5 parts of foaming component hydrogen peroxide and stir for 1 minute.

[0114] S6, immediately pour the solution into the prepared mold, use liquid nitrogen to freeze pore at -120℃ for 60 minutes. After freezing is completed, thaw to room temperature.

[0115] S7, after recovering to room temperature, put the mold as a whole into an oven for drying, the oven temperature is set to 80°, after drying is completed, the cement aerogel material sample S8 can be obtained.

[0116] Comparative Example

[0117] The difference between Comparative Example 1 and Example 1 is that polyethylene glycol is not added.

[0118] The difference between Comparative Example 2 and Example 1 is that reinforcing fiber is not added.

[0119] The difference between Comparative Example 3 and Example 1 is that Portland cement is used instead of sulphoaluminate cement.

[0120] The difference between Comparative Example 4 and Example 1 is that liquid nitrogen is used for freezing pore, the freezing temperature is -80℃ and the freezing time is 30 min.

[0121] The difference between Comparative Example 5 and Example 1 is that the amount of polyethylene glycol is 0.25 parts.

[0122] The difference between Comparative Example 6 and Example 1 is that the amount of polyethylene glycol is 0.65 parts

[0123] The difference between Comparative Example 7 and Example 1 is that the amount of reinforcing fiber is 0.25 parts.

[0124] The difference between Comparative Example 8 and Example 1 is that the length of the reinforcing fiber is 25-35 mm and the diameter is 10-15 μm.

[0125] The difference between Comparative Example 9 and Example 1 is that the length of the reinforcing fiber is 1-10 mm and the diameter is 1-10 μm.

[0126] The difference between Comparative Example 10 and Example 1 is that the amount of water is 10 parts.

[0127] Performance test

[0128] The samples obtained from the examples and comparative examples were subjected to performance test, and the test results are shown in Table 1. The compressive strength test method refers to GB / T 34336-2017, and the thermal conductivity refers to GB / T 10295. The control sample is a commercially available porous silica-calcium board HCS-20 from Hebei Huajun Thermal Insulation Material Co., Ltd.

[0129] Table 1 Performance test results

[0130] Compressive strength (MPa) Thermal conductivity (W / (m・K)) Density (kg / m 3 ) Comparative Example 0.54 0.063 220 Example 1 0.86 0.038 92 Example 2 0.87 0.043 106 Example 3 0.93 0.042 118 Example 4 0.91 0.041 112 Example 5 0.72 0.039 97 Example 6 0.87 0.037 89 Example 7 0.88 0.039 94 Example 8 0.85 0.038 90 Comparative Example 1 - - - Comparative Example 2 0.58 0.038 89 Comparative Example 3 0.28 0.091 185 Comparative Example 4 0.36 0.067 166 Comparative Example 5 0.68 0.047 118 Comparative Example 6 0.67 0.038 93 Comparative Example 7 0.63 0.044 105 Comparative Example 8 0.65 0.046 102 Comparative Example 9 0.59 0.041 97 Comparative Example 10 0.92 0.051 132

[0131] By comparing and analyzing the performance of the examples and the control example, it can be known that the thermal insulation material obtained by the application has more excellent thermal insulation performance, and at the same time the density is reduced, and it has good compressive strength, so that the sample has great advantages as a light-weight explosion-proof box thermal insulation filling material. Figures 1 to 3 As shown in the product-related performance diagram of Example 1, the pore structure of the product of Example 1 is uniform and orderly, which reduces the density and improves the strength of the material.

[0132] Further, by analyzing the performance of Comparative Example 1, it is found that Comparative Example 1 lacks a binding component and cannot be formed, and is a powder after freeze-drying. Further analysis of the performance of Comparative Example 5 shows that the amount of adhesive in Comparative Example 5 is reduced, and the performance of each phase is poor, which shows that the use of the adhesive in the application not only plays a role in adhesion, but also helps to disperse the reinforcing fiber and form an ordered pore structure. However, the further increase of the adhesive in Comparative Example 6 still results in poor performance, which shows that the amount of adhesive should be reasonably controlled to balance the performance of each phase, so as to achieve excellent comprehensive performance of the product.

[0133] Further, analyzing the performance of Comparative Example 2, it is found that Comparative Example 2 lacks reinforcing fibers, and the density and thermal conductivity are reduced, and the compressive strength is significantly reduced. In addition, in combination with the performance of Comparative Example 7, it is known that the use of reinforcing fibers cannot be too much, otherwise the negative impact on the product is greater. In addition, in combination with the performance of Comparative Example 8 and Comparative Example 9, it is known that the size of the reinforcing fibers has a certain influence on the product, because the reinforcing fibers not only improve the strength of the product, but the use of reinforcing fibers also has a certain influence on the pore structure of the product. The length of the reinforcing fibers used in the present application is 10-20mm, and the diameter is 10-15μm, which can better play a role in the system of the present application and improve the performance of the product.

[0134] Further, analyzing the performance of Comparative Example 3, it is found that Comparative Example 3 uses Portland cement, which has no support for strength, resulting in shrinkage of the sample during drying. In combination with the performance of Comparative Example 10, it is found that the control of the water-binder ratio is very important to the performance of the product.

[0135] Further, analyzing the performance of Comparative Example 4, it is found that the freezing temperature of Comparative Example 4 is low, the freezing speed is slow, and the freezing is not directional, and the strength of the sample after drying is greatly reduced, and the shrinkage is serious.

[0136] The specific embodiments are only an explanation of the present application, and are not a limitation of the present application. Those skilled in the art can make modifications to the embodiments without creative contribution after reading the present specification, as long as the modifications are within the scope of the claims of the present application.

Claims

1. A process for the preparation of a lightweight insulating cement aerogel material, characterized in that, The method comprises the following steps: S1: taking a binder and dissolving it in water, the mass ratio of the binder to water being (0.4-0.6):(14-18), and then cooling the solution to room temperature; the binder comprises at least one of agarose, sodium alginate, chitosan, hyaluronic acid, a polyacrylic acid derivative, sodium polyacrylate, polyethylene glycol, polyacrylamide, and polyurethane; S2: adding a dispersing agent to the solution of S1, and then adding cement, stirring uniformly, the mass ratio of the cement to water being (1-1.25):(14-18); the cement is sulphoaluminate cement or a mixture of sulphoaluminate cement and Portland cement; S3: adding a hydrophobic component and stirring uniformly; S4: adding a reinforcing fiber, stirring uniformly, the reinforcing fiber being at least one of a polymer fiber, a carbon fiber, and a glass fiber, the length of the reinforcing fiber being 10-20 mm, the diameter of the reinforcing fiber being 10-15 μm, and the mass ratio of the reinforcing fiber to cement being 0.2:(1-1.25); S5: adding a foaming component and stirring uniformly; S6: pouring the solution of S5 into a mold, using liquid nitrogen to freeze and form pores, and recovering to room temperature after the freezing and pore-forming is completed; S7: placing the mold and the product after the freezing and pore-forming is completed in an oven to dry, and obtaining a cement aerogel material after the drying is completed; in the step S6, the freezing and pore-forming is directional freezing, the freezing temperature is -120--180℃, and the time is 30-60 min.

2. A process for the preparation of a lightweight insulating cement aerogel material according to claim 1, characterized in that, In the step S2, the cement is added in at least two times.

3. A process for the preparation of a lightweight insulating cement aerogel material according to claim 1, characterized in that, The dispersing agent comprises at least one of a sulfonate water reducer, a naphthalene water reducer, and a polycarboxylic acid water reducer, and the mass ratio of the dispersing agent to cement is 0.03:(1-1.25).

4. A process for the preparation of a lightweight insulating cement aerogel material according to claim 1, characterized in that, The hydrophobic component comprises at least one of trimethoxysilane and triethoxysilane, and the mass ratio of the hydrophobic component to cement is 0.12:(1-1.25).

5. A process for the preparation of a lightweight insulating cement aerogel material according to claim 1, characterized in that, The foaming component is one of hydrogen peroxide, sodium bicarbonate, ammonium carbonate, and ammonium bicarbonate, and the mass ratio of the foaming component to cement is 0.5:(1-1.25).

6. A process for the preparation of a lightweight insulating cement aerogel material according to claim 1, characterized in that, In the step S7, the drying temperature is 50-80℃.

7. Use of a lightweight thermal insulation cement aerogel material prepared according to the process of any one of claims 1 to 6, characterized in that, The cement aerogel material is used as a heat insulation material for an explosion-proof box.

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