A fire-resistant and flame-retardant coated silicon-based coating material and its preparation method and application

Abstract

The present invention relates to the field of fire-resistant and flame-retardant technology, and specifically to a fire-resistant and flame-retardant coated silicon-based coating material, and its preparation method and application. The present invention provides a fire-resistant and flame-retardant coated silicon-based coating material, the coated silicon-based coating material includes a high-temperature resistant fiber substrate cloth and a first coating and a second coating coated on both sides of the high-temperature resistant fiber substrate cloth; wherein the raw materials of the first coating include silica gel, aluminum oxide, glass powder or glass microbeads, calcium aluminate, and a curing agent, and the raw materials of the second coating include silica gel or polyurea or polyurethane, expanded graphite, a curing material, ammonium molybdate, and a curing agent, and the curing material includes acrylamide, pentaerythritol, and melamine. The fire-resistant and flame-retardant coated silicon-based coating material provided by the present invention has both good fire-resistant and flame-retardant functions, is not easy to burn in a fire, and produces low smoke toxicity and very little smoke, and can realize live construction, which brings great convenience to the transformation of existing projects.

Description

Technical Field

[0001] The present invention relates to the technical field of fire resistance and flame retardancy, and in particular to a fire resistant and flame retardant coated silicon-based coating material, a preparation method thereof, and an application thereof. Background Art

[0002] A cable is a device that transmits electrical energy or signals, typically consisting of several conductors or groups of conductors. Cable fire protection generally has two distinct requirements: flame retardancy, which means the cable itself should not, or should participate as little as possible in combustion under fire or ignition sources, minimizing its impact on the expansion and spread of the fire; and fire resistance, which means the cable should maintain its basic function of carrying electricity under certain external fire conditions.

[0003] Currently, cable flame retardancy is generally achieved by adding flame-retardant materials to the cable sheath or applying fire-retardant coatings. Cable fire resistance is generally achieved by modifying the cable structure or adding fire-resistant materials. However, the following issues remain: 1. Whether flame-retardant or fire-resistant, cable fire retardancy only achieves flame retardancy, while fire resistance only achieves fire resistance. Therefore, it is currently impossible to achieve both flame retardancy and fire resistance simultaneously. 2. According to current national standards, the testing costs and cycle times for cable fire retardant coatings or cable sheaths are high, making it difficult to screen out substandard products, leading to a flood of substandard products on the market. Furthermore, due to the complex formulations of these materials, product consistency control is difficult. 3. As a key component of cable flame retardancy, cable fire retardant coatings are highly dependent on construction quality, and are prone to cracking and shedding due to environmental factors such as humidity, ultraviolet radiation, and alternating hot and cold temperatures. Consequently, their actual performance and service life are extremely low. 4. Due to the low compatibility between paints applied at different times or with different formulas, it is difficult to perform live operations without damaging or replacing the cables when repairing problems with cable fire retardant coatings or when the cable fire rating needs to be upgraded. 5. The current solutions and materials used for cable flame retardancy and cable fire resistance, whether it is the cable's own materials or structural design, or the cable fire retardant coating, are not recyclable and cannot be recycled. 6. The smoke toxicity of existing materials or coatings is relatively high, and the smoke production (smoke density) is relatively high. Once a fire occurs, it is easy to cause the risk of suffocation to people. 7. When a fire occurs outside the cable sheath, existing products cannot achieve "non-destructive" protection of the internal cables for a certain period of time, and the post-disaster repair cost is high; when a fire occurs inside the sheath, existing products cannot achieve internal "fire extinguishing" function. Summary of the Invention

[0004] In view of this, the present invention provides a fire-resistant, flame-retardant coated silicon-based coating material and its preparation method and application. The fire-resistant, flame-retardant coated silicon-based coating material has both good fire-resistant and flame-retardant functions, is not easy to burn in a fire, and produces low smoke toxicity and very little smoke.

[0005] To solve the above technical problems, the present invention provides a fire-resistant, flame-retardant coated silicon-based coating material, which includes a high-temperature resistant fiber substrate cloth and a first coating and a second coating coated on both sides of the high-temperature resistant fiber substrate cloth; wherein the raw materials of the first coating include 30wt%~60wt% of silica gel, 20wt%~40wt% of alumina, 15wt%~30wt% of glass powder or glass microbeads, 1wt%~2wt% of calcium aluminate, and 0.3wt%~3wt% of a curing agent; the raw materials of the second coating include 20wt%~50wt% of silica gel or polyurea or polyurethane, 8wt%~70wt% of expanded graphite, 2wt%~40wt% of a curing material, 1wt%~2wt% of ammonium molybdate, and 0.2wt%~2.5wt% of a curing agent, and the curing material includes acrylamide, pentaerythritol, and melamine.

[0006] The fire-resistant and flame-retardant coated silicon-based covering material provided by the present invention is coated with a coating having a specific composition on both sides of the high-temperature resistant fiber substrate cloth, and forms a first coating and a second coating respectively.

[0007] Among them, the first coating has the properties of UV resistance, resistance to alternating hot and cold, and waterproof. At the same time, in the high-temperature scenario of a fire, it can achieve the barrier to heat absorption and heat convection through a chemical-physical combined reaction.

[0008] The base material of the first coating is silicone, which primarily serves to bond and solidify the other active ingredients. Silicone exhibits excellent resistance to UV rays, alternating heat and cold, and water, and possesses excellent elasticity, allowing it to firmly adhere to the surface of the heat-resistant fiber substrate. In the event of a fire, the silicone component pyrolyzes at high temperatures to form amorphous SiO2. Aluminum oxide reacts with the SiO2 formed by the thermal decomposition of silicone under the intense heat of a fire to form a ceramic phase. This ceramic phase not only provides structural strength to the encapsulation material exposed to the intense heat of a fire, but also blocks convection and reduces radiant heat, thereby reducing the transfer of heat generated by the fire source to the objects within the encapsulation material. Glass powder or glass microbeads, through a physico-chemical synergistic reaction between 300 and 800°C, achieve ceramicization or quasi-ceramicization at lower temperatures. This bridges the temperature gap between the ceramic phase formed by the silicone and alumina at high temperatures in the later stages of a fire and the heat-resistant fiber substrate, ensuring fire protection for the encapsulated object in mid-fire or low-load fire scenarios.

[0009] Calcium aluminate, as a core additive in the first coating, has one function: to lower the initial temperature of the first coating's ceramicization. This addition can reduce the initial temperature from 600°C to 500°C. Furthermore, calcium aluminate reduces the porosity of the ceramic layer from 12%-15% to below 8%. Because the ceramic layer is thin and primarily functions to reflect radiant heat and reduce convective heat, its lower porosity enhances its fire resistance and flame retardancy for the entire structure. Furthermore, calcium aluminate improves the high-temperature strength of the ceramic layer. The addition of calcium aluminate increases the flexural strength of the ceramic layer at 800-1000°C (at high temperatures, cast iron blocks are added to the ceramic shell until the ceramic layer is broken) by approximately 40%.

[0010] Specifically, the main mechanism by which calcium aluminate plays a role in the first coating is:

[0011] (1) Low-temperature eutectic reaction: Calcium aluminate begins to react with glass powder or glass beads at 450°C to form a microscopic grid structure. Compared with the coating without calcium aluminate, the addition of calcium aluminate can reduce the reaction temperature of glass powder or glass beads by about 100°C, while promoting the thermal decomposition of silica gel to generate SiO2 to achieve rapid melting and infiltration, thus forming a dense ceramic layer. Through observation, it was found that at the same temperature, such as 600°C, the ceramic layer formed by the material with calcium aluminate added was more obvious and had a better gloss than that without calcium aluminate, which confirmed that the ceramic layer obtained by adding calcium aluminate was of higher quality.

[0012] (2) Interface enhancement and crystal phase regulation: Ca in calcium aluminate 2+ and Al 3+ It reacts with silica gel decomposition products (SiO2) to form calcium aluminum silicate (CaAl2SiO2), which fills the gaps between alumina particles and improves the flexural strength of the ceramic layer. Comparative testing was conducted by preparing samples without and with calcium aluminate, forming a ceramic layer at 600°C. After cooling, weights were added to the ceramic layer until it broke. The calculated structural flexural strength of the sample without calcium aluminate was approximately 3.25 MPa, while that of the sample with calcium aluminate was approximately 4.33 MPa, a 33.2% increase in structural flexural strength.

[0013] (3) Thermal expansion coefficient matching: The thermal expansion coefficient of calcium aluminate is between that of the silica gel matrix and alumina, which relieves the interfacial stress under high temperature gradient and prevents the ceramic layer from cracking. By preparing samples without adding calcium aluminate and adding calcium aluminate, and forming a ceramic layer at a high temperature of 600℃ for comparative testing, the cracking of the ceramic surface was observed after cooling. A 50mm×50mm area at the center of the sample was selected for observation. It was found that the sample without adding calcium aluminate had 6 cracks, the longest of which was 22mm; the sample with adding calcium aluminate had 2 cracks, the longest of which was 19mm. This shows that the addition of calcium aluminate relieves the interfacial stress under high temperature, prevents the ceramic layer from cracking, and significantly reduces the number and length of cracks.

[0014] The second coating has the function of producing physical and chemical synergistic changes under high temperature of fire, generating an expanded body with a large number of pores and excellent thermal stability. It can achieve thermal insulation protection for objects inside the coating material under external fire, and can also achieve fire extinguishing function through the suffocating effect of the expanded body when a fire occurs inside the coating material.

[0015] The base material for the second coating can be silicone, polyurea, polyurethane, or other materials with a certain degree of thermal stability, easy application, and sufficient surface strength and elasticity after curing. Taking fire-resistant cables as an example, the coating material provided by the present invention differs from the base material-based formulations used in fire-resistant cable sheath designs. In this invention, the base material primarily serves to solidify the active ingredients, providing a certain degree of ductility and weather resistance. Expanded graphite, through intercalation reactions and high-temperature thermal decomposition under the high temperatures of a fire, forms a structure with high porosity, low thermal conductivity, and high thermal stability within the cavity between the heat-resistant fiber substrate and the inner portion of the coating. The curing material, including acrylamide, pentaerythritol, and melamine, imparts mechanical strength to the expanded material through carbonization (the synergistic effect of acrylamide, pentaerythritol, and melamine), thereby preventing the expanded material from falling off. Ammonium molybdate, an innovative additive to the second coating, suppresses smoke production.

[0016] Ammonium molybdate has a catalytic effect and decomposes at 200-400°C to form nano-MoO3 particles. Through redox catalysis, it converts incompletely burned carbon particles into CO2. At the same time, it catalytically decomposes nitrogen-containing compounds (such as HCN) into N2 and H2O, reducing the toxicity of smoke. When the second coating uses a different substrate material (such as silicone, polyurea, or polyurethane), the smoke suppression mechanism of ammonium molybdate is as follows: When silicone is used as the substrate material, SiO2 generated by the high-temperature decomposition of silicone reacts with MoO3 to form molybdenum silicic acid (MoSi2O7), enhancing the high-temperature stability of the carbon layer and improving smoke suppression efficiency. When polyurethane is used as the substrate material, ammonium molybdate decomposes at 200-400°C to form nano-MoO3 particles. These particles, through acid catalysis, promote the dehydrogenation and cross-linking of the polyurethane, forming a dense graphitized carbon layer, thereby isolating oxygen, reducing the release of volatile combustibles, and lowering smoke production. When polyurea is used as the substrate material, ammonium molybdate decomposes at 200-400°C to form nano-MoO3 particles. These particles react with siloxane fragments (Si-O-Si) generated by the high-temperature decomposition of polyurea to form a molybdenum silicic acid ceramic layer. This ceramic layer has both high reflectivity and low thermal conductivity (0.1 W / m·K), reducing heat transfer to the substrate and inhibiting smoke production from the pyrolysis of organic matter.

[0017] Preferably, when the matrix material in the second coating layer is silicone, addition-type silicone, condensation-type silicone or other types of silicone can be selected.

[0018] Preferably, when the base material in the second coating layer is polyurea, a polyurea coating can be selected.

[0019] In conjunction with the first aspect, the curing material further comprises at least one of aluminum oxide and zinc borate. When the curing material further comprises at least one of aluminum oxide and zinc borate, the aluminum oxide and / or zinc borate can ceramicize the expanded body, thereby synergistically generating carbonization with acrylamide, pentaerythritol, and melamine to impart a certain mechanical strength to the expanded body, further preventing the expanded body from falling off.

[0020] In combination with the first aspect, the thickness of the first coating and the second coating are both 0.2~5mm. In actual applications, the thickness of the first coating and the second coating can be arbitrarily selected between 0.2~5mm according to the actual application scenario, for example, the thickness of the first coating is 0.2~3mm, and the thickness of the second coating is 2~4mm; or the thickness of the first coating is 3.5~4.5mm, and the thickness of the second coating is 0.5~3mm.

[0021] In combination with the first aspect, the particle size of the expanded graphite is 30-1000 mesh, and the expansion ratio is 50-500 times.

[0022] In conjunction with the first aspect, the high-temperature-resistant fiber substrate fabric is selected from at least one of ceramic fiber fireproof fabric, glass fiber fabric, high-silica fabric, and basalt fiber fabric. The high-temperature-resistant fiber substrate fabric selected in the present invention is non-flammable, has an oxygen index of 40% or higher, exhibits excellent thermal stability, has a long-term temperature resistance of 400°C or higher, and possesses high tensile strength, excellent toughness, and good surface adhesion, enabling the coating to adhere more firmly to the substrate fabric surface.

[0023] In combination with the first aspect, the thickness of the high temperature resistant fiber substrate cloth is 0.2-5 mm, and the mass per unit area is 20-5000 g / m 2 .

[0024] The second aspect of the present invention provides a method for preparing the above-mentioned refractory and flame-retardant coated silicon-based coating material, the steps comprising: adding one of the glass powder or glass microbeads and alumina and calcium aluminate to the silica gel in a preset proportion, and adding a colorant and filler as needed, stirring to make it evenly dispersed in the silica gel matrix, adding a curing agent and stirring evenly to obtain a first coating; adding the expanded graphite, curing material and ammonium molybdate to the silica gel or polyurea or polyurethane in a preset proportion, and adding a colorant and filler as needed, stirring to make it evenly dispersed in the silica gel or polyurea or polyurethane, adding a curing agent and stirring evenly to obtain a second coating; applying the first coating and the second coating to the two side surfaces of the high-temperature resistant fiber substrate cloth respectively, and obtaining the refractory and flame-retardant coated silicon-based coating material after the coating is cured.

[0025] In conjunction with the second aspect, the curing agent used can be adaptively selected according to different types of substrates.

[0026] In combination with the second aspect, the first coating and the second coating are respectively applied to both sides of the high temperature resistant fiber substrate cloth by roller coating, knife coating, brush coating or roller pressing to obtain a first coating and a second coating respectively.

[0027] The third aspect of the present invention provides an application of the above-mentioned fire-resistant, flame-retardant coated silicon-based coating material in fire-resistant protection of steel cables, fire-resistant protection of cable trough boxes, fire-resistant protection of steel structures, fire-resistant protection of aluminum alloy structures, fire-resistant protection of concrete structures, flame retardant and fire-resistant protection of wooden structures, fireproof sealing, fire-resistant protection of lithium batteries, fire protection of new energy vehicles and energy storage facilities, specifically: the fire-resistant, flame-retardant coated silicon-based coating material is used to coat the object to be fire-protected by bundling, Velcro, button fixation or mechanical fixation.

[0028] The present invention has developed a flexible, high-performance fire-resistant and flame-retardant material. In addition to its application in the field of cable fire protection, this material can also be used in areas requiring fire zoning and fire-resistant separation, such as building fire separation, fire sealing of power facility holes, and fire-resistant separation of new energy vehicles and facilities.

[0029] Preferably, for the bundling fixing method, metal cable ties such as stainless steel or non-metal cable ties such as high-temperature resistant fiber can be used to bundle the composite fireproof material coating on the surface of the object to be fire-protected. For the Velcro fixing method, the composite fireproof material can be cut to a suitable width according to the needs of the project, and the A and B sides of the flame-retardant Velcro can be sewn to the two ends of the composite fireproof material with high-temperature resistant thread respectively, and the Velcro can be used to form an enclosure structure for the protected object. For the button fixing method, the composite fireproof material can be cut to a suitable width according to the needs of the project, and the two ends can be fixed with buttons (such as buttons, snaps, etc.) to form an enclosure structure for the protected object. For the mechanical fixing method, the composite fireproof material can be cut to a suitable width according to the needs of the project, and the composite fireproof material can be directly fixed to the surface of the protected object by mechanical fixing methods such as strips and screws.

[0030] In combination with the third aspect, when the coating is performed, the coating direction is: the second coating layer of the coating material is close to the object to be protected from fire, and the first coating layer is away from the object to be protected from fire, that is, the second coating layer directly contacts the object to be coated directly inward, and the first coating layer contacts the fire source or smoke outward.

[0031] The present invention produces beneficial effects: Through the specific selection of coating components and combining them with a high-adhesion, high-temperature-resistant fiber substrate cloth, a coated silicon-based coating material is produced that is both fire-resistant and flame-retardant. This coating material achieves smoke toxicity levels of ZA1, with an optimal smoke density rating of SDR ≤ 3. It is non-combustible in fires, produces low smoke toxicity, and produces minimal smoke. It also exhibits excellent weather resistance and environmental adaptability. Furthermore, this coating material exhibits excellent insulation properties, with a withstand voltage of ≥1kV. Live construction is possible when voltage conditions are met, making it ideal for fireproofing upgrades in existing projects. When applied to the surface of a protected object, such as a base cable, this coating material significantly improves its flame retardancy (from B3 to B1) and significantly extends its fire resistance (from 6 minutes for the base cable to 105 minutes of continuous fire resistance), resulting in a fire resistance limit of at least 125 minutes. In addition, the coating material can not only be used for flame retardant and fire-resistant protection of cables in new construction projects, but can also be used for fire protection upgrades of existing projects or flexible fireproof partitions in new energy scenarios, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a photo of the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 1 of the present invention;

[0033] Figure 2 This is a photo of the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 2 of the present invention;

[0034] Figure 3This is a photo of the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 3 of the present invention;

[0035] Figure 4 This is a photo of the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 4 of the present invention;

[0036] Figure 5 This is a photo of the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 1 of the present invention being coated on the surface of a base cable and ignited during a fire test;

[0037] Figure 6 This is a photograph of the fire resistance limit moment (191 minutes) when the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 1 of the present invention was coated on the surface of a base cable and subjected to a fire resistance test;

[0038] Figure 7 This is a photograph of monitoring equipment showing the fire resistance limit moment (191 minutes) when the fire-resistant, flame-retardant coated silicon-based coating material obtained in Example 1 of the present invention was coated on the surface of a base cable and a fire resistance test was carried out;

[0039] Figure 8 This is a photo of the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 2 of the present invention being coated on the surface of a base cable and ignited during a fire test;

[0040] Figure 9 This is a photograph of the fire resistance limit moment (188 minutes) when the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 2 of the present invention was coated on the surface of a base cable and subjected to a fire resistance test;

[0041] Figure 10 This is a photograph of monitoring equipment showing the fire resistance limit moment (188 minutes) when the fire-resistant, flame-retardant coated silicon-based coating material obtained in Example 2 of the present invention was coated on the surface of a base cable and subjected to a fire resistance test;

[0042] Figure 11 This is a photo of the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 3 of the present invention being coated on the surface of a base cable and ignited during a fire resistance test;

[0043] Figure 12 This is a photograph of the fire resistance limit moment (128 minutes) when the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 3 of the present invention was coated on the surface of a base cable and subjected to a fire resistance test;

[0044] Figure 13 This is a photograph of monitoring equipment showing the fire resistance limit moment (128 minutes) when the fire-resistant, flame-retardant coated silicon-based coating material obtained in Example 3 of the present invention was coated on the surface of a base cable and a fire resistance test was carried out;

[0045] Figure 14 This is a photo of the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 4 of the present invention being coated on the surface of a base cable and ignited during a fire test;

[0046] Figure 15 This is a photograph of the fire resistance limit moment (133 minutes) when the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 4 of the present invention was coated on the surface of a base cable and subjected to a fire resistance test;

[0047] Figure 16 This is a photograph of monitoring equipment showing the fire resistance limit moment (133 minutes) when the fire-resistant and flame-retardant coated silicon-based coating material obtained in Example 4 of the present invention was coated on the surface of a base cable and a fire resistance test was carried out. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0049] Those skilled in the art will understand that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by those skilled in the art in the art to which the present invention pertains. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with those in the context of the prior art and, unless specifically defined, will not be interpreted in an idealized or overly formal sense.

[0050] At present, the products used for cable fire protection cannot take into account both flame retardancy and fire resistance at the same time, and the consistency of product quality is difficult to ensure. The flame retardant effect of fire retardant coatings is easily affected by construction quality and environmental factors. The coatings are prone to cracking and falling off, and the actual service life is short. Moreover, the compatibility of coatings from different batches or formulas is poor, which makes it difficult to perform live operations when repairing the coating or improving the fire protection level, and the cable needs to be replaced or shut down. Existing flame retardant / fire resistant materials (such as cable bodies or coatings) are not recyclable and do not conform to the concept of a circular economy. In addition, existing flame retardant or fire resistant materials are mostly based on organic matter as a carrier, which has the disadvantages of large smoke production and high toxicity during combustion. They can easily cause suffocation in fires and cause serious secondary hazards. Moreover, current fire retardant materials cannot protect cables from high-temperature losses, and the cost of post-disaster repair is high. At the same time, they lack "active" fire extinguishing functions and cannot effectively suppress the spread of fire.

[0051] The currently available "cable flame retardant tape" products mainly use PVC, EVA or EPDM rubber as base materials, which have high smoke toxicity and large smoke production. They can only be used for cable flame retardancy and cannot achieve cable fire protection. At the same time, they require winding construction, and the risk of live construction is relatively high. For existing projects, cables need to be moved, which makes construction difficult.

[0052] In view of this, the present invention provides a fire-resistant, flame-retardant coated silicon-based coating material, which has both flame-retardant and fire-resistant functions, and has the advantages of high oxygen index, low smoke production, and low smoke toxicity. It also has excellent weather resistance and insulation performance, and can upgrade other objects such as cables that do not have fire-proof functions to higher flame retardant and fire-resistant levels, while having greater cost advantages; moreover, for cables that already have fire-retardant coatings, the coating material will not be incompatible with the existing coatings, and is very suitable for fire-proof upgrade and renovation projects of existing projects.

[0053] Unless otherwise specified, the chemical reagents, raw materials, and mechanical equipment used in the following examples and comparative examples are conventional commercially available products.

[0054] Example 1

[0055] This embodiment provides a fire-resistant, flame-retardant coated silicon-based coating material, which includes a ceramic fiber fireproof cloth (thickness 0.5-1 mm) and a first coating layer and a second coating layer coated on both sides of the ceramic fiber fireproof cloth; wherein the raw materials of the first coating layer include 45 wt % of silica gel, 30 wt % of aluminum oxide, 23 wt % of glass powder, 1.7 wt % of calcium aluminate, and 0.3 wt % of a curing agent; the raw materials of the second coating layer include 40 wt % of addition-type silica gel, 40 wt % of expanded graphite (particle size 100 mesh, expansion ratio 50 times), 18 wt % of a curing material, 1.8 wt % of ammonium molybdate, and 0.2 wt % of a curing agent; and the curing material includes acrylamide, pentaerythritol, melamine, aluminum oxide, and zinc borate (the weight proportions in the second coating layer are 5 wt %, 5 wt %, 3 wt %, 2 wt %, and 3 wt %, respectively).

[0056] The actual picture of the coating material is as follows Figure 1 shown.

[0057] Example 2

[0058] This embodiment provides a fire-resistant, flame-retardant coated silicon-based coating material, which includes glass fiber cloth (thickness 1-3 mm) and a first coating layer and a second coating layer applied to both sides of the glass fiber cloth. The raw materials for the first coating layer include 30 wt % silica gel, 40 wt % alumina, 26 wt % glass powder, 1 wt % calcium aluminate, and 3 wt % curing agent. The raw materials for the second coating layer include 25 wt % condensed silica gel, 63 wt % expanded graphite (50 mesh particle size, 200-fold expansion ratio), 9 wt % curing material, 1 wt % ammonium molybdate, and 2 wt % curing agent. The curing material includes acrylamide, pentaerythritol, melamine, and alumina (the weight proportions of the second coating layer are 5 wt %, 2 wt %, 1 wt %, and 1 wt %, respectively).

[0059] The actual picture of the coating material is as follows Figure 2 shown.

[0060] Example 3

[0061] This embodiment provides a fire-resistant and flame-retardant coated silicon-based coating material, which includes a basalt fiber cloth (thickness 3-5 mm) and a first coating layer and a second coating layer applied to both sides of the basalt fiber cloth. The first coating layer comprises 60 wt % silica gel, 21 wt % aluminum oxide, 15.5 wt % glass microspheres, 1.5 wt % calcium aluminate, and 2 wt % curing agent. The second coating layer comprises 48.5 wt % polyurethane, 15 wt % expanded graphite (100 mesh particle size, 50 times expansion ratio), 33 wt % curing material, 2 wt % ammonium molybdate, and 1.5 wt % curing agent. The curing material comprises acrylamide, pentaerythritol, melamine, aluminum oxide, and zinc borate (the weight proportions of the second coating layer are 5 wt %, 10 wt %, 8 wt %, 3 wt %, and 7 wt %, respectively).

[0062] The actual picture of the coating material is as follows Figure 3 shown.

[0063] Example 4

[0064] This embodiment provides a fire-resistant, flame-retardant coated silicon-based coating material, which includes a high-silica cloth (thickness 2-4 mm) and a first coating layer and a second coating layer applied to both sides of the high-silica cloth. The first coating layer comprises 50 wt% silica gel, 20 wt% alumina, 28 wt% glass microbeads, 1 wt% calcium aluminate, and 1 wt% curing agent. The second coating layer comprises 20 wt% polyurea coating (containing a silicon oxide filler), 65.5 wt% expanded graphite (30 mesh particle size, 500-fold expansion ratio), 10 wt% curing material, 2 wt% ammonium molybdate, and 2.5 wt% curing agent. The curing material comprises acrylamide, pentaerythritol, melamine, and zinc borate (the weight proportions of which in the second coating layer are 4 wt%, 2 wt%, 2 wt%, and 2 wt%, respectively).

[0065] The actual picture of the coating material is as follows Figure 4 shown.

[0066] Example 5

[0067] This embodiment provides a method for preparing a fire-resistant and flame-retardant coated silicon-based coating material having a formula as in Example 1, the steps comprising:

[0068] S1. Stretching of high temperature resistant fiber base cloth before coating: Lay the ceramic fiber fireproof cloth flat on the coating platform (for reel-loaded base cloth, one end can be fixed on the feed port and a certain reverse torque can be applied to the reel to make the base cloth stretch out to a plane).

[0069] S2. Prepare the coating: add alumina, glass powder and calcium aluminate to the silica gel matrix, stir thoroughly to ensure that the raw materials are evenly distributed in the silica gel, add a curing agent and stir thoroughly to obtain a first coating; add expanded graphite, curing material and ammonium molybdate to the silica gel matrix, stir thoroughly to ensure that the raw materials are evenly distributed in the silica gel, add a curing agent and stir thoroughly to obtain a second coating.

[0070] S3. Applying coating: The first coating and the second coating obtained in step S2 are evenly applied to both sides of the ceramic fiber fireproof cloth by roller coating, and left to stand naturally to allow the coating to fully react and solidify on the ceramic fiber fireproof cloth. After drying, a fire-resistant and flame-retardant coated silicon-based coating material is obtained.

[0071] Example 6

[0072] This embodiment provides a method for preparing a fire-resistant and flame-retardant coated silicon-based coating material having a formula as in Example 2, the steps comprising:

[0073] S1. Stretching of high temperature resistant fiber substrate cloth before coating: Lay the glass fiber cloth flat on the coating platform (for reel-loaded substrate cloth, one end can be fixed on the feed port and a certain reverse torque can be applied to the reel to make the substrate cloth stretch out to a plane).

[0074] S2. Prepare the coating: add alumina, glass powder and calcium aluminate to the silica gel matrix, stir thoroughly to ensure that the raw materials are evenly distributed in the silica gel, add a curing agent and stir thoroughly to obtain a first coating; add expanded graphite, curing material and ammonium molybdate to the silica gel matrix, stir thoroughly to ensure that the raw materials are evenly distributed in the silica gel, add a curing agent and stir thoroughly to obtain a second coating.

[0075] S3. Applying coatings: The first coating and the second coating obtained in step S2 are evenly applied to both sides of the glass fiber cloth by brushing, and left to stand naturally to allow the coatings to fully react and solidify on the glass fiber cloth. After drying, a fire-resistant and flame-retardant coated silicon-based coating material is obtained.

[0076] Example 7

[0077] This embodiment provides a method for preparing a fire-resistant and flame-retardant coated silicon-based coating material having a formula as in Example 3, the steps comprising:

[0078] S1. Stretching of high temperature resistant fiber substrate cloth before coating: Lay the basalt fiber cloth flat on the coating platform (for reel-loaded substrate cloth, one end can be fixed on the feed port and a certain reverse torque can be applied to the reel to make the substrate cloth stretch out to a plane).

[0079] S2. Prepare the coating: add alumina, glass beads and calcium aluminate to a silica gel matrix, stir thoroughly to ensure that the raw materials are evenly distributed in the silica gel, add a curing agent and stir thoroughly to obtain a first coating; add expanded graphite, curing material and ammonium molybdate to a polyurethane matrix, stir thoroughly to ensure that the raw materials are evenly distributed in the polyurethane, add a curing agent and stir thoroughly to obtain a second coating.

[0080] S3. Coating: The first coating and the second coating obtained in step S2 are uniformly applied to both sides of the basalt fiber cloth by scraping, and left to stand naturally to allow the coatings to fully react and solidify on the basalt fiber cloth. After drying, a fire-resistant and flame-retardant coated silicon-based coating material is obtained.

[0081] Example 8

[0082] This embodiment provides a method for preparing a fire-resistant, flame-retardant coated silicon-based coating material having a formulation as in Example 4, the steps comprising:

[0083] S1. Stretching of high-temperature resistant fiber substrate cloth before coating: Lay the high-silica cloth flat on the coating platform (for reel-loaded substrate cloth, one end can be fixed on the feed port and a certain reverse torque can be applied to the reel to make the substrate cloth stretch out to a plane).

[0084] S2. Prepare the coating: add alumina, glass beads and calcium aluminate to a silica gel matrix, stir thoroughly to ensure that the raw materials are evenly distributed in the silica gel, add a curing agent and stir thoroughly to obtain a first coating; add expanded graphite, curing material and ammonium molybdate to a polyurea coating matrix, stir thoroughly to ensure that the raw materials are evenly distributed in the polyurea coating matrix, add a curing agent and stir thoroughly to obtain a second coating.

[0085] S3. Applying coating: The first coating and the second coating obtained in step S2 are evenly applied to both sides of the high-silica cloth by roller pressing, and left to stand naturally to allow the coating to fully react and solidify on the high-silica cloth. After drying, a fire-resistant and flame-retardant coated silicon-based coating material is obtained.

[0086] Comparative Example 1

[0087] This comparative example provides a fire-resistant, flame-retardant coated silicon-based coating material. The composition of the coating material is basically similar to that of Example 1, with the only difference being that the first coating does not contain calcium aluminate but is replaced by an equal amount of glass powder. The composition of the remaining raw materials is the same as that of Example 1, and the preparation method is similar to that of Example 4, with the only difference being that calcium aluminate is replaced by an equal amount of glass powder when preparing the first coating.

[0088] Comparative Example 2

[0089] This comparative example provides a fire-resistant, flame-retardant coated silicon-based coating material. The composition of the coating material is basically similar to that of Example 1, except that the second coating does not contain ammonium molybdate, but is replaced by an equal amount of expanded graphite. The remaining raw material composition is the same as that of Example 1, and the preparation method is similar to that of Example 4, except that ammonium molybdate is replaced by an equal amount of expanded graphite when preparing the second coating.

[0090] Comparative Example 3

[0091] This comparative example provides a fire-resistant, flame-retardant coated silicon-based coating material. The composition of the coating material is basically similar to that of Example 1, except that the curing material of the second coating does not contain melamine, but is replaced by an equal amount of pentaerythritol. The remaining raw material composition is the same as that of Example 1, and the preparation method is similar to that of Example 4, except that melamine is replaced by an equal amount of pentaerythritol when preparing the second coating.

[0092] Comparative Example 4

[0093] This comparative example provides a cable with a surface coated with a fire retardant coating, wherein the base cable is a cross-linked polyethylene insulated and polyethylene sheathed power cable YJV22-0.6 / 1kV-3*50+1*25 commonly used in engineering projects, and the components of the fire retardant coating coated on the surface of the base cable include 10wt%~40wt% of ammonium polyphosphate, 5wt%~20wt% of melamine, 2wt%~12wt% of pentaerythritol and 10wt%~30wt% of acrylic emulsion, and the balance is a mixture of ethanol and water, and the coating thickness is 1mm.

[0094] Comparative Example 5

[0095] This comparative example provides a cable provided with a protective sheath, wherein the base cable is a cross-linked polyethylene insulated polyethylene sheathed power cable YJV22-0.6 / 1kV-3*50+1*25 commonly used in engineering projects, and the material of the protective sheath used is glass fiber with a silicone coating on the surface and a ceramic fiber cloth lining, with a thickness of 3~4mm.

[0096] Test Example

[0097] The coating materials obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were respectively bundled and coated on the surface of a base cable having no flame retardant function and cross-linked polyethylene insulated polyethylene sheathed power cable YJV22-0.6 / 1kV-3*50+1*25 commonly used in engineering projects using cable ties made of high-temperature resistant fiber. The fire resistance and flame retardant properties were measured. At the same time, the uncoated base cable was used as a control, and the following properties of the different cables provided in Comparative Examples 4 to 5 were tested.

[0098] Among them, the flame retardant grade of the cable before and after coating is tested according to GB 31247-2014 "Classification of Fire Performance of Electric Cables and Optical Fiber Cables"; the fire resistance grade of the cable before and after coating is tested according to GB / T 19216.21-2003 "Line integrity test of electric or optical cables under flame conditions Part 21: Test procedures and requirements - Cables with rated voltage of 0.6 / 1.0kV and below"; Weathering test 1 includes corrosion resistance, water resistance, oil resistance, acid resistance, water resistance, moisture and heat resistance, and freeze-thaw cycle resistance tests according to GB 23864-2023 "Fireproof sealing materials"; Weathering test 2 includes heat exposure resistance, moisture and heat resistance, freeze-thaw cycle resistance, acid resistance, alkali resistance, salt spray corrosion resistance, and ultraviolet radiation resistance according to GB 14907-2018 "Fire retardant coatings for steel structures"; The oil resistance, salt water resistance, moisture and heat resistance, and freeze-thaw cycle resistance tests were carried out in accordance with GB / T 20285-2006 "Hazard Classification of Toxicity of Smoke Generation of Materials", the oxygen index of the material was tested in accordance with GB / T 2406.2-2009 "Determination of Combustion Behavior of Plastics by the Oxygen Index Method - Part 2: Room Temperature Test", and the smoke density level of the material was tested in accordance with GB / T 20284-2006 "Single-Unit Combustion Test for Building Materials or Products". The insulation performance of the material was tested using a multimeter. The test results are shown in Table 1.

[0099] Table 1

[0100]

[0101] As can be seen from Table 1, compared with non-fire-resistant base cables, the fire resistance limits of the cables protected by the coating materials obtained in Examples 1 to 4 are significantly increased from 6 minutes of the base cable to more than 125 minutes, and all meet the requirements that the fire-resistant cable can remain energized after 90 minutes of fire supply and 15 minutes of fire suspension, and the fire resistance limits are all over 125 minutes; the flame retardant performance is improved from B3 level to B1 level; while the fire resistance and flame retardant properties of the coating material are greatly improved, its weather resistance and actual withstand voltage are basically not reduced compared to the base cable, while the smoke density is greatly reduced and the smoke toxicity safety level is significantly improved. It can be seen that after the non-fire-resistant base cable is coated with the coating material provided by the embodiment of the present invention, the fire resistance, flame retardant performance, smoke toxicity, smoke density level and other combustion-related properties of the combined structure of the obtained coating material-cable are significantly improved.

[0102] Comparing Example 1 with Comparative Examples 1 to 3, it can be seen that after adjusting the formula of the first coating or the second coating, the synergistic effect between the effective ingredients is weakened to varying degrees, and the fire resistance, flame retardancy, smoke toxicity or smoke density level of the combined structure after the obtained coating material is coated on the base cable are deteriorated to varying degrees. This shows that there is a specific mutual synergistic effect between the components of the present invention, thereby forming a stable thermal insulation protective layer, which realizes the protection of the base cable under combustion conditions and is of great significance for suppressing the occurrence of adverse conditions such as smoke and toxicity during the combustion process.

[0103] Comparing Examples 1-4 with Comparative Example 4, a commonly used cable fire protection method—coating a cable fire retardant coating on the base cable surface—suggests that the present invention not only addresses the difficulties of cable fire retardant coating application and the impossibility of live work, but also addresses the poor weather resistance of cable fire retardant coatings. Furthermore, the present invention significantly improves fire resistance, smoke toxicity, and smoke density compared to Comparative Example 4.

[0104] Comparing Examples 1 to 4 with Comparative Example 5, which is a commonly used cable protection and fire prevention method at present, in which a cable protection sleeve is coated on the outer surface of the base cable, it can be seen that the flame retardant performance of Comparative Example 5 is worse than that of the present invention. At the same time, although the fire resistance limit is improved compared with the base cable, it still cannot meet the performance indicators of the fire-resistant cable, and the gap in fire resistance and flame retardant performance is large compared with the present invention.

[0105] Since the types of adhesive bases of the second coating differ among the various embodiments of the present invention, there are also differences in fire resistance and other aspects. Among them, Examples 1 and 2 use silica gel as the main adhesive, which is a silicon-based organic matter and has better flame retardant properties than carbon-based organic matter polyurethane and polyurea. Therefore, their fire resistance limits are significantly better than those of Example 3, in which the main body of the second coating is a polyurethane adhesive, and Example 4, in which the main body of the second coating is a polyurea adhesive. Similarly, the smoke density level indicators of Examples 1 and 2 are also significantly better than those of Examples 3 and 4. During the fire resistance test, Examples 3 and 4 experienced local visible flame combustion, but it was observed that the combustion was focused on the gaps in the formed coating structure, and the combustion process did not affect the protective effect of the coating material on the internal base cable. For Example 3, since the molecular structure of polyurethane will be destroyed by ultraviolet radiation, although it meets the weather resistance test 1 in the cable application field, in the fire resistance test 2 with ultraviolet radiation and the evaluation index of outdoor steel structure fire retardant coating, the ultraviolet attenuation is more obvious. Nevertheless, since the second coating containing polyurethane faces the cable, it is not affected by ultraviolet radiation in daily use, and therefore does not affect its actual use effect.

[0106] Moreover, the coating material provided by the present invention has good insulation properties and a withstand voltage of ≥1kV. It can be coated when the base cable is energized, which is of great significance to the fire protection engineering renovation of existing projects.

[0107] also, Figures 5 to 16 The following are on-site photos and monitoring equipment photos taken at different times during the fire resistance test. It can be seen that when the coating materials obtained in Examples 1 to 4 of the present invention were coated on the base cable and subjected to fire resistance testing, the coating material did not burn on a large scale during the fire resistance test. Although localized open flames occurred in Examples 3 and 4, they were actually burning in the gaps of the coating structure and did not affect the protected objects inside the coating structure. In addition, during the fire resistance test, the monitoring equipment found that (in order: Figure 7 、 Figure 10 、 Figure 13 and Figure 16 ), the base cable protected by the coating material can always remain energized (the four red bulbs in the top row are all lit, indicating that the cable is still energized), indicating that after the non-fire-resistant base cable is coated with the coating material, even if a fire occurs, the base cable can maintain normal working condition for a long time, reducing the losses caused by power outages due to fire.

[0108] The above is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solutions and inventive concepts of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A fire-resistant, flame-retardant coated silicon-based coating material, characterized in that: The coated silicon-based coating material comprises a high-temperature resistant fiber substrate cloth and a first coating and a second coating applied to both sides of the high-temperature resistant fiber substrate cloth; The raw materials of the first coating layer include 30wt%~60wt% of silica gel, 20wt%~40wt% of alumina, 15wt%~30wt% of glass powder or glass microbeads, 1wt%~2wt% of calcium aluminate, and 0.3wt%~3wt% of a curing agent; the raw materials of the second coating layer include 20wt%~50wt% of silica gel or polyurea or polyurethane, 8wt%~70wt% of expanded graphite, 2wt%~40wt% of a curing material, 1wt%~2wt% of ammonium molybdate, and 0.2wt%~2.5wt% of a curing agent, and the curing material includes acrylamide, pentaerythritol, and melamine.

2. The fire-resistant and flame-retardant coated silicon-based coating material according to claim 1, characterized in that: The solidification material further includes at least one of aluminum oxide and zinc borate.

3. The fire-resistant and flame-retardant coated silicon-based coating material according to claim 1, characterized in that: The thickness of the first coating layer and the second coating layer are both 0.2-5 mm.

4. The fire-resistant and flame-retardant coated silicon-based coating material according to claim 1, characterized in that: The particle size of the expanded graphite is 30-1000 meshes, and the expansion ratio is 50-500 times.

5. The fire-resistant and flame-retardant coated silicon-based coating material according to any one of claims 1 to 4, characterized in that: The high temperature resistant fiber substrate cloth is selected from at least one of ceramic fiber fireproof cloth, glass fiber cloth, high silica cloth and basalt fiber cloth.

6. The fire-resistant and flame-retardant coated silicon-based coating material according to claim 5, characterized in that: The thickness of the high temperature resistant fiber base cloth is 0.2-5 mm, and the mass per unit area is 20-5000 g / m 2 .

7. The method for preparing the fire-resistant and flame-retardant coated silicon-based coating material according to any one of claims 1 to 6, characterized in that the steps include: Adding one of the glass powder or glass microbeads, aluminum oxide, and calcium aluminate to the silica gel in a preset ratio, stirring until uniformly dispersed, adding a curing agent, and stirring evenly to obtain a first coating; Adding the expanded graphite, curing material and ammonium molybdate to the silica gel or polyurea or polyurethane in a preset ratio, stirring until uniformly dispersed, adding a curing agent and stirring evenly to obtain a second coating; The first coating and the second coating are respectively applied to both side surfaces of the high temperature resistant fiber substrate cloth, and the fire resistant and flame retardant coated silicon-based covering material is obtained after the coatings are cured.

8. The method for preparing a fire-resistant and flame-retardant coated silicon-based coating material according to claim 7, characterized in that: The first coating and the second coating are respectively applied to both sides of the high-temperature resistant fiber substrate cloth by roller coating, blade coating or brush coating.

9. Use of the fire-resistant, flame-retardant coated silicon-based coating material according to any one of claims 1 to 6 in fire protection of steel cables, fire protection of cable trough boxes, fire protection of steel structures, fire protection of aluminum alloy structures, fire protection of concrete structures, flame retardant and fire protection of wooden structures, fireproof sealing, fire protection of lithium batteries, fire protection of new energy vehicles and energy storage facilities, characterized in that: The fire-resistant, flame-retardant coated silicon-based covering material is used to cover the object to be fire-protected by bundling, Velcro, button or mechanical fixing.

10. The use according to claim 9, characterized in that During the coating process, the coating direction is: the second coating layer of the coating material is close to the object to be fire-protected, and the first coating layer is away from the object to be fire-protected.

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