Preparation method of full-dimensional cement-based super-infiltration insulator material

Abstract

The invention discloses a preparation method of a full-dimensional cement-based super-infiltration insulator material. The preparation method comprises the following steps: obtaining Portland cement slurry; sequentially adding a silane coupling agent and an ultra-infiltration modifier into the Portland cement slurry to obtain first mixed slurry; compounding calcium carbonate particles, diatomite and hydrophobic silicon dioxide particles with different particle sizes in the first mixed slurry, uniformly stirring, and then adding an active mineral admixture to obtain second mixed slurry; and carrying out compression molding and curing treatment on the second mixed slurry, and demolding and curing to obtain the full-dimensional cement-based super-infiltration insulator material. The full-dimensional insulator does not depend on a surface functional coating, a low-temperature compression molding process is adopted, a super-hydrophobic block material with a compact interior and a multi-stage rough surface structure is formed, the material body has super-infiltration, high mechanical strength and high electrical insulation performance, and then the problem of pollution flashover prevention of electrical equipment is fundamentally solved.

Description

Technical Field

[0001] This invention relates to the field of insulator technology, and in particular to a method for preparing a full-dimensional cement-based superwetting insulator material. Background Technology

[0002] Insulators are key components in power systems, providing electrical isolation and mechanical support. Their surface properties directly affect the safe operation of the power grid under high voltage and harsh environments. Pollution flashover is one of the major faults threatening the safe and stable operation of the power grid. It refers to the phenomenon where contaminants adhering to the insulator surface form a conductive film under humid conditions (such as fog, dew, or drizzle), leading to a decrease in insulation performance and ultimately flashover discharge. Statistics show that under specific environmental conditions, pollution flashover faults account for a significant proportion of high-voltage line faults, causing substantial economic losses.

[0003] To improve the anti-flashover capability of insulators, current technical approaches mainly focus on surface functionalization modification, namely, constructing superhydrophobic or super-dual-hydrophobic (hereinafter collectively referred to as "superwetting") coatings on the surface of traditional insulators (such as ceramic and glass insulators). These technologies typically apply low surface energy materials or nanoparticles (such as nano-silica) containing fluorine / silanes through spraying or dip coating to form a lotus leaf-like micro / nano structure on the surface, achieving waterproofing and oil resistance. However, this surface coating-dependent approach has inherent and insurmountable limitations: First, poor interface reliability and rapid performance degradation: The coating and substrate are essentially physically bonded, with a clear heterogeneous interface. Under the complex operating conditions faced by power equipment over long periods, the coating is prone to peeling and cracking due to insufficient interfacial adhesion, leading to a rapid decline in superwetting performance. Second, it introduces weak points in the insulation, increasing the risk of breakdown: The interface between the coating and the substrate may contain microscopic defects or discontinuities. These areas are prone to forming electric field concentrations or water bridges in humid or high-voltage environments, which may induce partial discharge or even breakdown, increasing the overall insulation safety risks of the insulator. Third, the process is complex and the life-cycle cost is high: Existing coating technologies (including some improved coatings and their application devices) typically rely on fine multi-layer spraying or complex surface treatment processes, which are complex. More importantly, once the coating is damaged during use, on-site repair is extremely difficult and maintenance costs are high, failing to meet the requirements of long life and high reliability for power equipment. In recent years, some research has attempted to develop composite insulators by modifying materials (such as adding modified fillers to silicone rubber) to improve hydrophobicity and corona resistance. However, such methods can still be regarded as a "surface functionalization" approach (functional layer coated on the substrate), or there are problems such as difficulty in balancing mechanical and electrical properties, without fundamentally changing the "functional layer depends on the substrate" model. In summary, current superwetting insulator technology has failed to break through the inherent paradigm of "substrate + functional coating," and its core contradiction lies in the reliability, lifespan, and insulation safety issues brought about by the coating-substrate interface.

[0004] Therefore, developing a fully solid-state functional material that possesses superwetting properties, high mechanical strength, and stable electrical insulation properties in its bulk (rather than its surface) to achieve true "structure-function" integration is a key direction for solving the problem of flashover prevention in power equipment and promoting technological innovation. Summary of the Invention

[0005] In view of this, this application provides a method for preparing a full-dimensional cement-based super-wetting insulator material to solve the problem of anti-pollution flashover in solid insulators for power equipment.

[0006] To achieve the above technical objectives, this application adopts the following technical solution: In a first aspect, this application provides a method for preparing a multidimensional cement-based superwetting insulator material, comprising the following steps: Obtain silicate cement slurry; A silane coupling agent and a super-wetting modifier are added sequentially to the silicate cement slurry to obtain a first mixed slurry; Different particle sizes of calcium carbonate particles, diatomaceous earth and hydrophobic silica particles are compounded in the first mixed slurry. After stirring evenly, active mineral admixtures are added to obtain the second mixed slurry. The second mixed slurry is molded and cured, and after demolding and curing, the all-dimensional cement-based super-wetted insulator material is obtained.

[0007] Preferably, the water-cement ratio of the silicate cement slurry is 0.25-0.4:1.

[0008] Preferably, the superwetting modifier is one or more of fluorinated silanes and fluorine-free silanes.

[0009] Preferably, the ratio of the super-wetting modifier to the silicate cement slurry is 0.025-0.05 ml / g.

[0010] Preferably, the active mineral admixture includes one or more of fly ash and slag powder.

[0011] Preferably, the ratio of the active mineral admixture to the silicate cement slurry is 0.05-0.15 g / g.

[0012] Preferably, the calcium carbonate particles include micron-sized calcium carbonate particles and nano-sized calcium carbonate particles; the ratio of the calcium carbonate particles to the silicate cement slurry is 0.05-0.15 g / g.

[0013] Preferably, the diatomite is micron-sized diatomite; the ratio of the diatomite to the silicate cement slurry is 0.05-0.15 g / g.

[0014] Preferably, the hydrophobic silica particles are nano-sized hydrophobic silica particles; the ratio of the hydrophobic silica particles to the silicate cement slurry is 0.025-0.05 g / g.

[0015] Preferably, the temperature of the molding and curing process is 5-10℃, and the time is 1-2 days. The beneficial effects of this application are as follows: The all-dimensional insulator of this application does not rely on surface functional coatings. It adopts a low-temperature molding process and utilizes multi-component and size synergistic control of the chemical composition and microstructure of the material to form a superhydrophobic bulk material with a dense internal structure and a multi-level rough surface. The material body has superwetting (the water and oil contact angles on its surface and any cross-section are all above 150°), high mechanical strength and high electrical insulation performance, thus fundamentally solving the problem of pollution flashover prevention in power equipment. Attached Figure Description

[0016] Figure 1 Photographs of the static contact angles of water and oil in the all-solid superhydrophobic cement-based material prepared in Example 1.

[0017] Figure 2 Photographs of water and oil on any cross-section after the all-solid superhydrophobic cement-based material prepared in Example 1 was destroyed.

[0018] Figure 3 Photographs of the static contact angles of water and oil after 720 hours of immersion in water for the all-solid superhydrophobic cement-based material prepared in Example 1.

[0019] Figure 4 , Figure 5 and Figure 6 The images show the static contact angles of the all-solid superhydrophobic cement-based material prepared in Example 1 after being immersed in 5% hydrochloric acid, sodium hydroxide, and sodium chloride solutions for 24 hours at 25°C, respectively, for water and oil.

[0020] Figure 7 Photographs showing the static contact angles of water and oil in the all-solid superhydrophobic cement-based material prepared in Example 1 after a 720-hour artificial climate aging test.

[0021] Figure 8 Photographs showing the static contact angles of water and oil on the all-solid superhydrophobic cementitious material prepared in Example 1 after 150 cycles of wear.

[0022] Figure 9 The images show surface and cross-sectional SEM images of the all-solid superhydrophobic cementitious material prepared in Example 2.

[0023] Figure 10 Photographs of the static contact angles of water and oil in the all-solid superhydrophobic cement-based material prepared in Example 2.

[0024] Figure 11 Photographs of water and oil on any cross-section after the all-solid superhydrophobic cement-based material prepared in Example 2 was destroyed.

[0025] Figure 12 Photographs of the static contact angles of water and oil after 720 hours of immersion in water for the all-solid superhydrophobic cement-based material prepared in Example 2.

[0026] Figure 13 , Figure 14 and Figure 15 The images show the static contact angles of the all-solid superhydrophobic cement-based material prepared in Example 2 after being immersed in 5% hydrochloric acid, sodium hydroxide, and sodium chloride solutions for 24 hours at 25°C, respectively, for water and oil.

[0027] Figure 16 Photographs showing the static contact angles of water and oil in the all-solid superhydrophobic cement-based material prepared in Example 2 after a 720-hour artificial climate aging test.

[0028] Figure 17 Photographs showing the static contact angles of water and oil on the all-solid superhydrophobic cementitious material prepared in Example 2 after 150 cycles of wear.

[0029] Figure 18 Photograph of the static water contact angle of the all-solid superhydrophobic cementitious material prepared in Example 3.

[0030] Figure 19 The image shows water on any cross-section after the all-solid superhydrophobic cementitious material prepared in Example 3 was destroyed.

[0031] Figure 20 Photograph of the static water contact angle of the all-solid superhydrophobic cement-based material prepared in Example 3 after 720 hours of water immersion.

[0032] Figure 21 , Figure 22 and Figure 23 The images show the static water contact angles of the all-solid superhydrophobic cementitious material prepared in Example 3 after being immersed in 5% hydrochloric acid, sodium hydroxide, and sodium chloride solutions for 24 hours at 25°C.

[0033] Figure 24 Photograph of the static contact angle of water after 720 hours of artificial climate aging test on the all-solid superhydrophobic cement-based material prepared in Example 3.

[0034] Figure 25 Photographs showing the static contact angle of water after 150 cycles of wear on the all-solid superhydrophobic cement-based material prepared in Example 3.

[0035] Figure 26Photographs of the static contact angles of water and oil in the all-solid superhydrophobic cement-based material prepared for Comparative Example 1.

[0036] Figure 27 Photographs of the static contact angles of water and oil after 720 hours of immersion in water for the all-solid superhydrophobic cement-based material prepared for Comparative Example 1.

[0037] Figure 28 , Figure 29 and Figure 30 The images show the static contact angles of the all-solid superhydrophobic cementitious material prepared in Comparative Example 1 after being immersed in 5% hydrochloric acid, sodium hydroxide, and sodium chloride solutions for 24 hours at 25°C, respectively, for water and oil.

[0038] Figure 31 Photographs of the static contact angles of water and oil in the all-solid superhydrophobic cement-based material prepared for Comparative Example 1 after 720 hours of artificial climate aging test.

[0039] Figure 32 Photographs showing the static contact angles of water and oil after 150 cycles of wear on the all-solid superhydrophobic cement-based material prepared for Comparative Example 1.

[0040] Figure 33 Photographs of the static contact angles of water and oil in the all-solid superhydrophobic cement-based material prepared for Comparative Example 2.

[0041] Figure 34 Photographs of the static contact angles of water and oil after 720 hours of immersion in water for the all-solid superhydrophobic cement-based material prepared for Comparative Example 2.

[0042] Figure 35 , Figure 36 and Figure 37 The static contact angles of the all-solid superhydrophobic cementitious material prepared in Comparative Example 2 after being immersed in 5% hydrochloric acid, sodium hydroxide, and sodium chloride solutions for 24 hours at 25℃ are shown in the photographs.

[0043] Figure 38 Photographs of the static contact angles of water and oil in the all-solid superhydrophobic cement-based material prepared for Comparative Example 2 after 720 hours of artificial climate aging test.

[0044] Figure 39 Photographs showing the static contact angles of water and oil after 150 cycles of wear on the all-solid superhydrophobic cement-based material prepared for Comparative Example 2.

[0045] Figure 40 The graph shows the relationship between wear quality and wear cycle number for Examples 1, 2, 3, Comparative Example 1, and Comparative Example 2.

[0046] Figure 41The graph shows the relationship between water absorption rate and time for Examples 1, 2, 3, Comparative Example 1, and Comparative Example 2.

[0047] Figure 42 This is a physical image of the insulator prepared for the application example of Example 2. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0049] This application provides a method for preparing a full-dimensional cement-based superwetting insulator material, comprising the following steps: S1. Obtain silicate cement slurry; S2. A silane coupling agent and a super-wetting modifier are added sequentially to the silicate cement slurry to obtain a first mixed slurry; S3. Calcium carbonate particles, diatomaceous earth and hydrophobic silica particles of different particle sizes are compounded in the first mixed slurry, and after being stirred evenly, active mineral admixtures are added to obtain the second mixed slurry. S4. The second mixed slurry is subjected to molding and curing treatment, and after demolding and curing, the all-dimensional cement-based super-wetting insulator material is obtained.

[0050] The all-dimensional insulator of this application does not rely on surface functional coatings. It adopts a low-temperature molding process and utilizes multi-component and size synergistic control of the chemical composition and microstructure of the material to form a superhydrophobic bulk material with a dense internal structure and a multi-level rough surface. The material body has superwetting (the water and oil contact angles on its surface and any cross-section are all above 150°), high mechanical strength and high electrical insulation performance, thus fundamentally solving the problem of pollution flashover prevention in power equipment.

[0051] Specifically, this application, firstly, introduces silane coupling agents and low surface energy materials (fluorinated or non-fluorinated silanes) to perform superwetting modification on all solid components, including cement particles, calcium carbonate particles, diatomaceous earth, and silica, during the material preparation stage. This allows the modified particles to possess low surface energy characteristics on their surfaces while forming a microstructure during cement hydration, thus exhibiting superwetting performance on any cross-section of the material. This improvement in superwetting performance is achieved without relying on any surface functional coatings. Superwetting modification of all solid components also simultaneously enhances the material's properties. Firstly, regarding surface resistivity, this application optimizes the water-cement ratio and incorporates active mineral admixtures to optimize hydration products through pozzolanic reaction. This reduces the porosity of the hydration products, improves the microstructure, and increases the bulk resistivity of the material, thereby enhancing its electrical insulation. Simultaneously, the reduced porosity also improves its mechanical strength. Secondly, by utilizing the different particle sizes of calcium carbonate particles, diatomaceous earth, and hydrophobic silica particles, multi-scale particle packing is achieved. These cross-size particles form mechanical interlocking and interlocking effects during hydration, directly enhancing the material's compressive strength. Furthermore, the three particle sizes are modified by a modifier, resulting in superwetting properties. The hydrophobic effect of the particles themselves improves the interfacial transition zone in the cement block, allowing for a more complete cement hydration reaction and reducing the presence of free water within the material, thus improving electrical insulation.

[0052] The above processes are all integrated in situ during mixing and cement hydration. Unlike the technical approach of functional coating on the substrate load surface, the all-dimensional insulator of this application realizes the integrated manufacturing of function and structure. It not only has super-wetting, high mechanical strength and high electrical insulation performance, but also these properties remain stable under high voltage or humid environments, and even if damaged, it does not need to be repaired.

[0053] In existing technologies, superwetting insulator materials heavily rely on surface functional coatings, resulting in performance, lifespan, and reliability limited by the interfacial bonding quality between the coating and the substrate. This application directly prepares a fully solid-state material with superwetting, high mechanical strength, and electrical insulation properties from the material body itself (rather than the conventional surface), thereby fundamentally avoiding interfacial failure problems such as coating peeling and cracking. In existing technologies, because the coating and substrate are heterogeneous materials, microscopic defects and discontinuities are prone to exist at their interface, becoming weak points of electric field concentration and increasing the risk of moisture penetration and breakdown. The fully solid-state material of this application has a uniform and dense microstructure, high mechanical properties, and electrical insulation properties, ensuring that its intrinsic electrical insulation properties remain stable and reliable under high voltage or humid environments. In existing technologies, the multi-layer spraying functionalization process is cumbersome, requires strict process control, and is difficult to repair on-site after damage, resulting in high production costs and difficulties in large-scale application. The fully solid-state material of this application has a simple process flow, is easy to integrate and mold, and is suitable for large-scale manufacturing.

[0054] In step S1, the step of obtaining silicate cement slurry is to stir at high speed within a limited water-cement ratio range to obtain silicate cement slurry. The stirring time is 5-10 minutes to ensure that the system is evenly dispersed and without obvious agglomeration.

[0055] In step S2, under high-speed stirring conditions, a silane coupling agent is first added and stirred for 5-10 minutes. Then, a superwetting modifier, either fluorinated or non-fluorinated silane, is added and stirred for 2-5 minutes to form a first mixed slurry with superwetting function. The purpose of adding the silane coupling agent first in this step is to improve the compatibility of the components within the cement slurry and to create active sites for the subsequent reaction between the modifier and cement particles. Controlling the dosage of the silane coupling agent and the superwetting modifier can enable some cement particles to possess superwetting properties. Cement particles with superwetting properties can improve cement fluidity, promote hydration reactions, reduce internal free water, and enhance electrical insulation.

[0056] In step S3, the compounding of calcium carbonate particles, diatomaceous earth, and hydrophobic silica particles of different particle sizes refers to the compounding of micron-sized and nano-sized calcium carbonate particles, micron-sized diatomaceous earth, and nano-sized hydrophobic silica particles, adding them to the first slurry, stirring at high speed for 5-10 minutes, and then adding active mineral admixtures to form a second slurry with electrical insulation and superwetting functions. The addition of these particle sizes fills the pores, improves mechanical properties (compressive strength), and enhances electrical insulation. In terms of material types, in this step, calcium carbonate particles are used to increase the density of the material and enhance mechanical strength; diatomaceous earth is used to improve the pore system; and hydrophobic silica is used to participate in the construction of low specific surface energy microstructures and improve compactness.

[0057] In step S4, the second slurry is poured into a container with a volume of 2x2x2cm. 3 In the mold, after low-temperature molding and curing, the sample is demolded and then wet-cured for 7 days at 20-25℃ and relative humidity ≥95%, followed by dry curing at room temperature for 28 days. This yields a multi-dimensional cement-based super-wetting material with high insulation, super-wetting properties, and high mechanical strength. Step S4 involves low-temperature molding to reduce water evaporation and ensure the accuracy of the water-cement ratio. Molding also densifies the cement slurry, reducing large pores and increasing compressive strength.

[0058] In some embodiments, the water-cement ratio of the silicate cement slurry is 0.25-0.4:1.

[0059] In this embodiment, if the slurry is too dry and thick, it will have poor fluidity, making it difficult to stir and form, and it will be prone to internal defects and low density. Conversely, if the slurry is too dry and thick, the material porosity will increase, the structure will be loose, and the mechanical strength and electrical insulation properties (such as volume resistivity and dielectric strength) will decrease significantly.

[0060] In some embodiments, the silane coupling agent includes one or more of γ-aminopropyltriethoxysilane KH550, γ-methacryloxypropyltrimethoxysilane KH-570, and γ-(2,3-epoxypropoxy)propyltrimethoxysilane KH-560; the amount of silane coupling agent used is 0.5 ml, and the ratio of the ash cement used is 0.02-0.03 mL / g.

[0061] In this embodiment, if there is too little silane coupling agent, it will not be able to fully coat inorganic particles such as cement, which will weaken the bridging effect between the silane and the superwetting modifier such as fluorinated silane added later, affecting the stability of the superwetting function. If there is too much, it may introduce too much organic matter, interfere with the cement hydration process, have an adverse effect on the mechanical strength of the material, and may also cause self-agglomeration, affecting the dispersion effect.

[0062] In some embodiments, the superwetting modifier is one or more of fluorinated silanes and fluorine-free silanes.

[0063] In this embodiment, the superwetting modifier includes fluorinated silanes and fluorine-free silanes, specifically including, but not limited to, one or more of the following: perfluorodecyltrimethoxysilane (1H,1H,2H,2H-Perfluorodecyltrimethoxysilane), perfluorodecyltriethoxysilane (1H,1H,2H,2H-Perfluorodecyltriethoxysilane), perfluorooctyltriethoxysilane (1H,1H,2H,2H-Perfluorooctyltriethoxysilane), nonafluorohexyltrimethoxysilane ((1,1,2,2-Tetrahydrononafluorohexyl)trimethoxysilane), hexamethyldisilazane, methyltrimethoxysilane, chlorotrimethylsilane, and n-octyltriethoxysilane.

[0064] In this embodiment, the wetting modifier is a substance containing low surface energy groups - methyl and carbon-fluorine bonds, which can improve the superwetting (superhydrophobic or superamphophobic) properties of the material.

[0065] In some embodiments, the ratio of the super-wetting modifier to the silicate cement slurry is 0.025-0.05 ml / g.

[0066] In this embodiment, if the amount of superwetting modifier is too small, the surface energy of the material will not be reduced sufficiently, and the superwetting property cannot be effectively constructed, resulting in the contact angle not meeting the standard. If the amount is too large, the excess modifier may not be able to bond completely and effectively, forming a weak layer, or hindering the normal hydration of cement, affecting the integrity and strength of the material.

[0067] In some embodiments, the active mineral admixture includes one or more of fly ash and slag powder.

[0068] In some embodiments, the ratio of the active mineral admixture to the silicate cement slurry is 0.05-0.15 g / g.

[0069] In this embodiment, if the amount of active mineral admixture is too small, the volcanic ash reaction will be insufficient, the filling effect on harmful pores and the optimization effect on hydration products will be limited, and the improvement of microstructure will not be obvious. If the amount is too large, the excessive admixture may cause the cementitious system to become unbalanced, affecting the hydration of the main cementitious materials, which is not conducive to the development of early strength.

[0070] In some embodiments, the calcium carbonate particles include micron-sized calcium carbonate particles and nano-sized calcium carbonate particles (mass ratio of 1:1); the ratio of the calcium carbonate particles to the silicate cement slurry is 0.05-0.15 g / g.

[0071] In this embodiment, if the amount of calcium silicate particles is too small, the filling and reinforcing effect on the cement matrix will be insufficient, the microstructure will not be dense enough, and the improvement of mechanical properties will be limited. If the amount is too large, the particles are prone to agglomeration, forming stress concentration points in the matrix, which may reduce the strength and affect the workability of the slurry.

[0072] In some embodiments, the diatomite is micron-sized diatomite; the ratio of the diatomite to the silicate cement slurry is 0.05-0.15 g / g.

[0073] In this embodiment, weather resistance and mechanical properties are related to water erosion. If there is too little diatomite, its filling and structural adjustment effects on pores will be weak, and the improvement in the weather resistance of the material will not be significant. If there is too much diatomite, its porous nature will adsorb a large amount of water, which may increase the porosity of the material and have a negative impact on its density and electrical insulation.

[0074] In some embodiments, the hydrophobic silica particles are nano-sized hydrophobic silica particles; the ratio of the hydrophobic silica particles to the silicate cement slurry is 0.025-0.05 g / g.

[0075] In this embodiment, if there are too few hydrophobic silica particles, the nanofilling effect and pozzolanic activity will not be fully realized, and the improvement of material densification and superwetting will be limited. If too many particles are used, the extremely high specific surface area will result in a large water requirement, which will easily lead to viscous slurry, poor workability, and easy agglomeration of nanoparticles, affecting uniformity.

[0076] In some embodiments, the temperature of the molding curing process is 5-10°C, the time is 1-2 days, and the curing pressure is 1-2 MPa.

[0077] In this embodiment, low temperature reduces water evaporation in the system, ensuring the accuracy of the water-cement ratio; molding is used to compact the cement slurry, reducing the presence of large pores to increase compressive strength.

[0078] The following specific embodiments further illustrate this solution.

[0079] Example 1 A method for preparing a full-dimensional cement-based superwetting insulator material includes the following steps: S1. Add 20g of lime cement and 6g of deionized water to a beaker, and stir at 800r / min for 8min to make silicate cement slurry; S2. Under high-speed stirring conditions of 800 r / min, add 0.5 mL of KH-560 silane coupling agent to silicate cement slurry, stir for 8 min, then add 0.75 mL of super hydrophobic modifier perfluorodecyltriethoxysilane, stir for 3 min, and obtain the first mixed slurry; S3. Add 1g of calcium carbonate particles with a mixed micron and nano particle size (mass ratio of 1:1, nano-sized particles are 20-100nm; micron-sized particles are 1-5μm) to the first mixed slurry, 1g of diatomaceous earth with a micron particle size (2-5μm) and 0.75g of hydrophobic silica particles with a nano particle size (15±5nm), stir at high speed of 800r / min for 8min, and then add 2g of fly ash to obtain the second mixed slurry; S4. Pour the slurry into a 2x2x2cm3 mold, and use low-temperature molding to cure for 1 day. Then demold and cure. The low-temperature molding process conditions are: temperature controlled at 5℃ and pressure at 1MPa. The curing conditions are: wet curing the demolded sample at 20℃ and relative humidity ≥95% for 7 days, and then transferring it to room temperature dry curing conditions for 28 days to obtain the all-dimensional cement-based super-wet insulator material.

[0080] Example 2 A method for preparing a full-dimensional cement-based superwetting insulator material is the same as in Example 1, except that 1 mL of the superhydrophobic modifier perfluorodecyltriethoxysilane is added.

[0081] Example 3 A method for preparing a full-dimensional cement-based superwetting insulator material is the same as in Example 1, except that 1 mL of the superhydrophobic modifier n-octyltriethoxysilane is added.

[0082] Comparative Example 1 A method for preparing a full-dimensional cement-based superwetting insulator material includes the following steps: S1. Add 20g of lime cement and 6g of deionized water to a beaker, stir at high speed for 8 minutes to make silicate cement slurry; S2. Under high-speed stirring conditions, add 0.5 mL of KH-560 silane coupling agent to silicate cement slurry, stir for 8 min, then add 1 mL of super hydrophobic modifier perfluorodecyltriethoxysilane, stir for 3 min, and obtain the first mixed slurry; S3. Pour the first mixed slurry into a container with a volume of 2x2x2cm. 3 The sample is placed in a mold and cured at room temperature (25℃) for 1 day in the absence of air. Then it is demolded and cured. The curing conditions are as follows: the demolded sample is wet cured at 20℃ and relative humidity ≥95% for 7 days, and then transferred to room temperature dry curing conditions for 28 days to obtain the all-dimensional cement-based super-wet insulator material.

[0083] Comparative Example 2 A method for preparing a full-dimensional cement-based superwetting insulator material includes the following steps: S1. Add 20g of lime cement and 6g of deionized water to a beaker, and stir at 800r / min for 8min to make silicate cement slurry; S2. Under high-speed stirring conditions of 800 r / min, add 0.5 mL of KH-560 silane coupling agent to silicate cement slurry, stir for 8 min, then add 1 mL of super hydrophobic modifier perfluorodecyltriethoxysilane, stir for 3 min, and obtain the first mixed slurry; S3. Add 1g of calcium carbonate particles with a mixed micron and nano particle size (mass ratio of 1:1, nano-sized particles are 20-100nm; micron-sized particles are 1-5μm) to the first mixed slurry, 1g of diatomaceous earth with a micron particle size (2-5μm) and 0.75g of hydrophobic silica particles with a nano particle size (15±5nm), stir at high speed of 800r / min for 8min, and then add 2g of fly ash to obtain the second mixed slurry; S4. Pour the slurry into a container with a volume of 2x2x2cm. 3 The sample is placed in a mold and cured at room temperature (25℃) for 1 day in the absence of air. Then it is demolded and cured. The curing conditions are as follows: the demolded sample is wet cured at 20℃ and relative humidity ≥95% for 7 days, and then transferred to room temperature dry curing conditions for 28 days to obtain the all-dimensional cement-based super-wet insulator material.

[0084] Comparative Example 3 A method for preparing a full-dimensional cement-based superwetted insulator material is the same as in Example 1, except that no silane coupling agent is added.

[0085] Comparative Example 4 A method for preparing a full-dimensional cement-based superwetting insulator material is the same as in Example 1, except that no low surface energy material is added.

[0086] Comparative Example 5 A method for preparing a full-dimensional cement-based superwetted insulator material is described, which is the same as in Example 1 except that no active mineral admixtures are added.

[0087] Testing and Evaluation Take a volume of 2x2x2cm 3 For the cement specimen, place it centered on the lower platen of the compression testing machine. Note that the side of the specimen should be the pressure-bearing surface (i.e., the side facing upwards and downwards during molding), and use a ball seat between the specimen and the upper platen to assist in leveling. Ensure uniform pressure distribution. Set the test bench movement speed to 5 mm / min to start the test, and record the pressure at maximum as the compressive strength.

[0088] Artificial climate aging test: A xenon arc lamp capable of simulating the full spectrum of the sun was used as the light source, with irradiance controlled at 550±50W / m²; the temperature was controlled at a blackboard temperature of 63±3°C (to monitor the surface temperature of the sample) and an air temperature inside the chamber of approximately 50°C; the relative humidity was set within the range of 50% to 70% to simulate the annual average humidity conditions of the material's location; in addition, the test employed periodic spraying (spraying water for 18 minutes and stopping spraying for 102 minutes), with deionized water used for the spraying.

[0089] Water absorption test Sample preparation: Drill or cut cylindrical samples with a diameter of approximately 100 mm and a thickness of approximately 50 mm from the cured cement specimens. Pretreatment and drying: Place the samples in an oven and dry them at 100°C to constant weight, then place them in a desiccator to cool to room temperature. (This step is to ensure that the initial state of the samples is consistent and completely dry).

[0090] Sealing and initial weighing: Immediately after cooling, weigh the dried mass of the sample. Then, completely seal the circumferential and bottom surfaces of the sample with epoxy resin, leaving only the test surface exposed.

[0091] Immersion and water absorption: Place the sample with the exposed surface facing down, slightly above the bottom of the water tank. Add deionized water to the tank until the water surface touches the exposed surface of the sample and start timing. Quickly remove the sample at different time intervals, gently blot dry the water outside the exposed surface with a damp cloth, weigh immediately, and quickly put it back. Record the mass increment for each weighing. The water absorption rate (i) is usually calculated using the formula i=Δm / (A×d), where Δm is the mass change (g), A is the area exposed in water (mm²), and d is the density of water (g / mm³).

[0092] Performance of the sample obtained in Example 1: Contact angle testing showed that the static water contact angle of the all-solid superhydrophobic cement-based material reached 165.0°, and the static oil contact angle was 152.0°. Figure 1 The cross-section also exhibits super-dual hydrophobic properties. Figure 2 The compressive strength is 34.0779 MPa; after 720 hours of water immersion testing, the static water contact angle of the all-solid super-hydrophobic cement-based material remains at 162.0°, and the static oil contact angle is 151.0°. Figure 3 At 25°C, after immersing the material in 5% hydrochloric acid, sodium hydroxide, and sodium chloride solutions for 24 hours, the static water contact angles were 160.7°, 165.5°, and 164.7°, respectively, and the static oil contact angles were 149.1°, 152.4°, and 154.1°, respectively. Figures 4-6 After 720 hours of artificial climate aging test, the static water contact angle of the all-solid superhydrophobic cement-based material remained at 165.0°, and the static oil contact angle was 152.1°. Figure 7 Using 80-grit sandpaper as the grinding media and applying a pressure of 50 kPa, after 150 rotations of a 10cm diameter rotary abrasion surface, the static water contact angle was 156.3° and the static oil contact angle was 138.4°. Figure 8 It loses its superoleophobic properties; the wear weight is 3.9117g ( Figure 40 The water absorption rate test results showed that after 720 hours, its water absorption rate was 0.3073% ( ); Figure 41 ).

[0093] Performance of the sample obtained in Example 2: SEM image of the obtained product (Figure 9) and contact angle test ( Figure 10 This indicates that the obtained bulk material has a rough surface, a static water contact angle of 167.2°, and a static oil contact angle of 157.0°. The cross-section also exhibits the same rough structure and superhydrophobic properties. Figure 11 The compressive strength is 43.9602 MPa; after 720 hours of water immersion testing, the static water contact angle of the all-solid super-hydrophobic cement-based material remains at 166.5°, and the static oil contact angle is 159.6°. Figure 12At 25°C, after immersing the material in 5% hydrochloric acid, sodium hydroxide, and sodium chloride solutions for 24 hours, the static water contact angles were 162.0°, 166.6°, and 167.4°, respectively, and the static oil contact angles were 155.0°, 156.8°, and 154.5°, respectively. Figures 13-15 After 720 hours of artificial climate aging test, the static water contact angle of the all-solid super-hydrophobic cement-based material remained at 166.0°, and the static oil contact angle was 153.6°. Figure 16 Using 80-grit sandpaper as the grinding media and applying a pressure of 50 kPa, after 150 rotations of a 10cm diameter rotary abrasion surface, the static water contact angle was 153.3° and the static oil contact angle was 143.8°. Figure 17 It loses its superoleophobic properties; the wear weight is 3.4077g ( Figure 40 The water absorption rate test results showed that after 720 hours, its water absorption rate was 0.2507% ( ); Figure 41 ).

[0094] Performance of the sample obtained in Example 3: Contact angle test showed that the static water contact angle reached 172.0° ( Figure 18 This endows the material with excellent superhydrophobic properties, and the cross-section also exhibits superhydrophobic properties. Figure 19 The compressive strength is 48.1406 MPa; after 720 hours of water immersion testing, the static water contact angle of the all-solid superhydrophobic cement-based material remains at 168.0°. Figure 20 Under conditions of 25℃, after immersing the material in 5% hydrochloric acid, sodium hydroxide, and sodium chloride solutions for 24 hours, the static water contact angles were 163.3°, 165.3°, and 170.4°, respectively. Figures 21-23 After 720 hours of artificial climate aging test, the static water contact angle of the all-solid super-hydrophobic cement-based material remained at 171.6°. Figure 24 Using 80-grit sandpaper as the grinding surface and applying a pressure of 50 kPa, after 150 rotations with a diameter d = 10 cm, the static water contact angle was 165.0°. Figure 25 It still exhibits excellent superhydrophobic properties; the wear mass is 3.0672g ( Figure 40 The water absorption rate test results showed that after 720 hours, its water absorption rate was 0.2052% ( ); Figure 41 ).

[0095] The performance of the sample obtained in Comparative Example 1 was tested under the same conditions as in Example 2. The prepared sample underwent contact angle testing, showing that the static water contact angle of the all-solid superhydrophobic cement-based material reached 160.0°, and the static oil contact angle was 130.2°. Figure 26The compressive strength is 24.5942 MPa; after 720 hours of water immersion testing, the static water contact angle of the all-solid superhydrophobic cement-based material remains at 156.6°, and the static oil contact angle is 127.1°. Figure 27 At 25°C, after immersing the material in 5% hydrochloric acid, sodium hydroxide, and sodium chloride solutions for 24 hours, the static water contact angles were 155.4°, 156.6°, and 158.6°, respectively, and the static oil contact angles were 124.0°, 126.5°, and 125.3°, respectively. Figures 28-30 After 720 hours of artificial climate aging test, the static water contact angle of the all-solid super-hydrophobic cement-based material remained at 158.0°, and the static oil contact angle was 128.3°. Figure 31 Using 80-grit sandpaper as the grinding media and applying a pressure of 50 kPa, after 150 rotations of a 10cm diameter rotary abrasion surface, the static water contact angle was 119.6° and the static oil contact angle was 85.5°. Figure 32 The wear mass is 5.0769g. Figure 40 The water absorption rate test results showed that after 720 hours, its water absorption rate was 0.3543% ( ); Figure 41 ).

[0096] The performance of the sample obtained in Comparative Example 2 was tested under the same conditions as in Example 2. The prepared sample underwent contact angle testing, showing that the static water contact angle of the all-solid superhydrophobic cement-based material reached 163.2°, and the static oil contact angle was 143.8°. Figure 33 The compressive strength is 27.3605 MPa; after 720 hours of water immersion testing, the static water contact angle of the all-solid super-hydrophobic cement-based material remains at 161.8°, and the static oil contact angle is 142.0°. Figure 34 At 25°C, after immersing the material in 5% hydrochloric acid, sodium hydroxide, and sodium chloride solutions for 24 hours, the static water contact angles were 159.6°, 160.3°, and 162.0°, respectively, and the static oil contact angles were 138.9°, 140.0°, and 142.5°, respectively. Figures 35-37 After 720 hours of artificial climate aging test, the static water contact angle of the all-solid super-hydrophobic cement-based material remained at 160.0°, and the static oil contact angle was 140.0°. Figure 38 Using 80-grit sandpaper as the grinding surface and applying a pressure of 50 kPa, after 150 rotations of a 10cm diameter abrasive, the static water contact angle was 148.0° and the static oil contact angle was 112.6°. Figure 39 The wear mass was 4.8321g. Figure 40 The water absorption rate test results showed that after 720 hours, its water absorption rate was 0.3155% ( ); Figure 41 ).

[0097] The performance of the sample obtained from Comparative Example 3 was tested as follows: static water contact angle was 135.1°, static oil contact angle was 112.2°, and compressive strength was 33.0799 MPa.

[0098] The performance of the sample obtained from Comparative Example 4 was tested as follows: static water contact angle was 97.8°, static oil contact angle was 69.5°, and compressive strength was 42.6489 MPa.

[0099] The performance of the sample obtained from Comparative Example 5 was tested as follows: static water contact angle was 150.8°, static oil contact angle was 131.8°, and compressive strength was 32.7452 MPa.

[0100] The slurry obtained by scaling up the dosage of all embodiments and comparative examples proportionally was used to prepare insulators using a low-temperature molding process. The surface resistivity, volume resistivity, and dielectric strength obtained after testing are shown in Table 1. The slurry obtained by scaling up the dosage of Example 2 proportionally was used to prepare insulators using a low-temperature molding process. Figure 42 Its surface resistivity is 0.56 × 10⁻⁶. 11 Ω, volume resistivity 0.34×10 11 It has a dielectric strength of 17.36 kV / mm and an Ω·m, exhibiting excellent electrical properties (electrical insulation).

[0101] Table 1 Test Results

[0102] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a multidimensional cement-based superwetting insulator material, characterized in that, Includes the following steps: Obtain silicate cement slurry; A silane coupling agent and a super-wetting modifier are added sequentially to the silicate cement slurry to obtain a first mixed slurry; Different particle sizes of calcium carbonate particles, diatomaceous earth and hydrophobic silica particles are compounded in the first mixed slurry. After stirring evenly, active mineral admixtures are added to obtain the second mixed slurry. The second mixed slurry is molded and cured, and after demolding and curing, the all-dimensional cement-based super-wetted insulator material is obtained.

2. The method for preparing the all-dimensional cement-based superwetting insulator material according to claim 1, characterized in that, The water-cement ratio of the silicate cement slurry is 0.25-0.4:

1.

3. The method for preparing the all-dimensional cement-based superwetting insulator material according to claim 1, characterized in that, The superwetting modifier is one or more of fluorinated silanes and fluorine-free silanes.

4. The method for preparing the all-dimensional cement-based superwetting insulator material according to claim 1, characterized in that, The ratio of the super-wetting modifier to the silicate cement slurry is 0.025-0.05 ml / g.

5. The method for preparing the all-dimensional cement-based superwetting insulator material according to claim 1, characterized in that, The active mineral admixture includes one or more of fly ash and slag powder.

6. The method for preparing the all-dimensional cement-based superwetting insulator material according to claim 1, characterized in that, The ratio of the active mineral admixture to the silicate cement slurry is 0.05-0.15 g / g.

7. The method for preparing the all-dimensional cement-based superwetting insulator material according to claim 1, characterized in that, The calcium carbonate particles include micron-sized calcium carbonate particles and nano-sized calcium carbonate particles; the ratio of the calcium carbonate particles to the silicate cement slurry is 0.05-0.15 g / g.

8. The method for preparing the all-dimensional cement-based superwetting insulator material according to claim 1, characterized in that, The diatomite is micron-sized diatomite; the ratio of the diatomite to the silicate cement slurry is 0.05-0.15 g / g.

9. The method for preparing the all-dimensional cement-based superwetting insulator material according to claim 1, characterized in that, The hydrophobic silica particles are nano-sized hydrophobic silica particles; the ratio of the hydrophobic silica particles to the silicate cement slurry is 0.025-0.05 g / g.

10. The method for preparing the all-dimensional cement-based superwetting insulator material according to claim 1, characterized in that, The temperature for the molding and curing process is 5-10℃, and the time is 1-2 days.

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