Fire-resistant and flame-retardant coating type silicon-based cladding material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of fire resistance and flame retardance, in particular to a fire-resistant and flame-retardant coating type silicon-based cladding material as well as a preparation method and application thereof. The invention provides a fire-resistant and flame-retardant coating type silicon-based cladding material. The coating type silicon-based cladding material comprises high-temperature-resistant fiber base material cloth, a first coating and a second coating, wherein the surfaces of the two sides of the high-temperature-resistant fiber base material cloth are coated with the first coating and the second coating; wherein raw materials of the first coating comprise silica gel, aluminum oxide, glass powder or glass beads, calcium aluminate and a curing agent, raw materials of the second coating comprise silica gel or polyurea or polyurethane, expanded graphite, a curing material, ammonium molybdate and a curing agent, and the curing material comprises acrylamide, pentaerythritol and melamine. The fire-resistant and flame-retardant coating type silicon-based cladding material provided by the invention has good fire-resistant and flame-retardant functions at the same time, is not easy to combust in a fire disaster, has low smoke toxicity and extremely low smoke yield, can realize live-line construction, and brings great convenience to transformation of existing projects.

Description

Technical Field

[0001] The present invention relates to the technical field of fireproof and flame-retardant technologies, and particularly relates to a fireproof and flame-retardant coated silicon-based coating material, a preparation method thereof, and an application thereof. Background Art

[0002] A cable is a device for transmitting electric energy or signals, usually composed of several or several groups of wires. There are generally two different requirements for cable fire protection. One is cable flame retardancy, that is, the cable itself does not participate or participates as little as possible in combustion under the action of a fire or a fire source, and the influence on the expansion and spread of the fire is reduced as much as possible; the other is cable fire resistance, that is, under certain external fire conditions, the basic function of the cable to be energized can still be maintained.

[0003] At present, cable flame retardancy is generally carried out by adding flame retardant materials to the cable outer skin or applying cable fireproof coatings, etc. Cable fire resistance is generally achieved by changing the cable structure, adding fireproof materials, etc. However, there are still the following problems: 1. For cable flame retardancy, whether it is through cable outer skin flame retardancy or applying cable fireproof coatings, only the flame retardant function of the cable can be achieved, and for cable fire resistance, only the fire resistance function can be achieved. Therefore, at present, it is impossible to simultaneously achieve the flame retardant and fire resistance functions of the cable. 2. According to the current national standards, the detection cost of cable fireproof coating products or cable outer skin is relatively high, the detection cycle is relatively long, and it is difficult to screen unqualified products, resulting in unqualified products flooding the market; at the same time, due to the overly complex formula of material products, it is difficult to control product consistency. 3. As a key product for current cable flame retardancy, the flame retardant performance of cable fireproof coatings is highly correlated with the construction quality, and due to external environmental factors such as humidity, ultraviolet radiation, and alternating hot and cold, problems such as cracking and peeling are likely to occur, and the actual use effect and sustainability of the service life are extremely low. 4. Due to the low compatibility between coatings applied at different times or coatings with different formulas, it is very difficult to perform live operations without damaging the cable or replacing the cable in the case of engineering repairs for problems with cable fireproof coating layers or situations where the cable fire protection level needs to be improved. 5. The current cable flame retardant and cable fire resistance schemes and materials, whether it is the cable itself material or structure design, or applying cable fireproof coatings, the materials are not recyclable and cannot be recycled. 6. The smoke toxicity of existing materials or coatings is relatively large, and the smoke production amount (smoke density) is relatively large, and once a fire occurs, it is easy to cause the risk of suffocation for personnel. 7. When a fire occurs outside the cable coating body, existing products cannot achieve "non-destructive" protection of the internal cable for a certain period of time, and the post-disaster repair cost is relatively high; when a fire occurs inside the coating body, existing products cannot also achieve the internal "fire extinguishing" function. Summary of the Invention

[0004] In view of this, the present invention provides a fire-resistant and flame-retardant coated silicon-based cladding material, a preparation method thereof and an application thereof. The fire-resistant and flame-retardant coated silicon-based cladding material has good fire-resistant and flame-retardant functions at the same time, is not easy to burn in a fire, has low smoke toxicity and extremely low smoke production.

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

[0006] The fire-resistant and flame-retardant coated silicon-based cladding material provided by the present invention coats coatings with specific compositions on both side surfaces of the high-temperature resistant fiber base cloth, and forms a first coating and a second coating respectively.

[0007] Among them, the first coating has properties such as ultraviolet resistance, cold and heat alternation resistance and waterproofness, and can achieve the blocking of heat absorption and heat convection through chemical-physical combination reactions in the high-temperature scenario of a fire.

[0008] The matrix material of the first coating is silica gel, and its main function is to bond and cure other active ingredients. Silica gel has good ultraviolet resistance, cold and heat alternation resistance and water resistance, and excellent elasticity, and can firmly adhere to the surface of the high-temperature resistant fiber base cloth. When a fire occurs, the silica gel component pyrolyzes at high temperature to form amorphous SiO2. Alumina can react with SiO2 formed by the thermal decomposition of silica gel at high fire temperature to form ceramic phase substances. These ceramic phase substances can not only provide structural strength for the cladding material in the high-temperature fire, but also block heat convection and reduce radiant heat, thereby reducing the transfer of heat generated by the fire source to the objects inside the cladding material. Glass powder or glass microspheres can achieve ceramization or pseudo-ceramization reactions at lower temperatures through physical-chemical synergistic reactions such as melting within 300 - 800°C, filling the temperature difference between the ceramic phase substances formed by silica gel and alumina at high temperature and the high-temperature resistant fiber base cloth in the later stage of the fire, and realizing the fire protection of the object covered by the cladding material in the medium-term of the fire or in the fire scenario with lower load.

[0009] Calcium aluminate is the core additive of the first coating. One of its functions is to lower the starting temperature of the ceramization of the first coating. The addition of calcium aluminate can reduce the starting temperature of the ceramization of the first coating from 600 °C to 500 °C. Moreover, calcium aluminate can reduce the porosity of the porcelain-forming layer from 12% - 15% to less than 8%. Since the porcelain-forming layer is relatively thin and its main functions are to reflect radiant heat and reduce convective heat, a lower porosity will improve its fire resistance and flame retardancy effects on the entire structure. In addition, calcium aluminate can also increase the high-temperature strength of the porcelain-forming layer. After adding calcium aluminate, the flexural strength of the porcelain-forming layer at 800 - 1000 °C (cast iron blocks are added to the porcelain-forming shell at high temperature until the porcelainized layer is damaged) increases by about 40%.

[0010] Specifically, the main mechanism by which calcium aluminate plays a role in the first coating is as follows: (1) Eutectic reaction at low temperature: Calcium aluminate starts to react with glass powder or glass microspheres at 450 °C to form a microscopic network structure. Compared with the coating without the addition of calcium aluminate, the addition can reduce the reaction temperature of glass powder or glass microspheres by about 100 °C, and at the same time promote the thermal decomposition of silica gel to generate SiO2 for rapid melting and infiltration, thus forming a dense ceramic layer. Through observation, it is found that at the same temperature, such as 600 °C, the porcelainized layer formed by the material with the addition of calcium aluminate is more obvious and has a better luster than that without the addition, which verifies that the quality of the ceramic layer obtained by adding calcium aluminate is higher.

[0011] (2) Interface strengthening and crystal phase regulation: Ca 2+ and Al 3+ in calcium aluminate react with the decomposition product of silica gel (SiO2) to form calcium aluminosilicate (CaAl2SiO2), filling the gaps between alumina particles and enhancing the flexural strength of the ceramic layer. By preparing samples without the addition of calcium aluminate and samples with the addition of calcium aluminate, and conducting a comparative test by forming a porcelainized layer under the action of a high temperature of 600 °C. After cooling, weights are added to the surface of the porcelainized layer of the sample until it breaks. It is calculated that the structural flexural strength of the sample without the addition of calcium aluminate is about 3.25 MPa, while the structural flexural strength of the sample with the addition of calcium aluminate is about 4.33 MPa, and the structural flexural strength increases by 33.2%.

[0012] (3) Thermal expansion coefficient matching: The thermal expansion coefficient of calcium aluminate is between that of the silica gel matrix and alumina, which alleviates the interfacial stress under high temperature gradients and avoids cracking of the ceramic layer. By preparing samples with and without calcium aluminate respectively, and forming a porcelainized layer under the action of a high temperature of 600 °C for comparative testing, when observing the cracking situation on the ceramic surface after cooling, a 50 mm × 50 mm area at the center of the sample was selected for observation. It was found that the sample without calcium aluminate had 6 cracks, with the longest crack being 22 mm; the sample with calcium aluminate had 2 cracks, with the longest crack being 19 mm, indicating that the incorporation of calcium aluminate alleviated the interfacial stress at high temperatures, avoided cracking of the ceramic layer, and significantly reduced the number and length of the cracks.

[0013] The second coating has the function of generating a physical-chemical synergistic change at high fire temperatures to form an expandable body with a large number of pores and excellent thermal stability, which can achieve heat insulation protection for the objects inside the coated material under an external fire, and can also achieve a fire extinguishing function through the suffocation effect of the expandable body when a fire occurs inside the coated material.

[0014] The matrix material of the second coating can be silica gel, polyurea, polyurethane or other materials with certain thermal stability, easy to apply, and having a certain surface strength and elasticity after curing. Taking a fire-resistant cable as an example, the coated material provided by the present invention is different from the formula with the matrix material as the main component in the fire-resistant design of the cable outer skin. In the present invention, the main function of the matrix is to cure the active ingredients, and it has a certain ductility and weather resistance. At high fire temperatures, expanded graphite forms a structure with high porosity, low thermal conductivity and excellent thermal stability in the cavity between the high-temperature resistant fiber base cloth and the objects inside the coated material through the synergistic action of intercalation reaction and high-temperature thermal decomposition. The curing materials include acrylamide, pentaerythritol and melamine, and their function is to enable the expandable body to have a certain mechanical strength through carbonization (synergistic action of acrylamide, pentaerythritol and melamine), thereby preventing the expandable body from falling off. Ammonium molybdate, as an innovative additive for the second coating, has the effect of inhibiting the generation of smoke.

[0015] Ammonium molybdate has a catalytic effect. It decomposes into nano-MoO3 particles at 200 - 400 °C. 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 the smoke. When different matrix materials are used for the second coating (such as silica gel, polyurea or polyurethane), the mechanism of the smoke inhibition effect of ammonium molybdate is as follows: When silica gel is selected as the matrix material, the SiO2 generated by the high-temperature decomposition of silica gel reacts with MoO3 to form silicomolybdate (MoSi2O7), enhancing the high-temperature stability of the carbon layer and improving the smoke inhibition efficiency at the same time; When polyurethane is selected as the matrix material, ammonium molybdate decomposes into nano-MoO3 particles at 200 - 400 °C. Through acid catalysis, it promotes the dehydrogenation crosslinking of polyurethane to form a dense graphitized carbon layer, thereby isolating oxygen and reducing the release of volatile combustibles, reducing the amount of smoke generated; When polyurea is selected as the matrix material, ammonium molybdate decomposes into nano-MoO3 particles at 200 - 400 °C, and reacts with the siloxane fragments (Si-O-Si) generated by the high-temperature decomposition of polyurea to form a silicomolybdate ceramic layer. This ceramic layer has both high reflectivity and low thermal conductivity (0.1 W / m·K), which can reduce the heat transfer to the substrate and inhibit the pyrolysis and smoke generation of organic substances.

[0016] Preferably, when the matrix material in the second coating is silica gel, addition-type silica gel or condensation-type silica gel or other types of silica gel can be selected.

[0017] Preferably, when the matrix material in the second coating is polyurea, polyurea coatings can be selected.

[0018] Combined with the first aspect, the curing material further includes at least one of alumina and zinc borate. When the curing material also contains at least one of alumina and zinc borate, alumina and / or zinc borate can play the role of ceramicizing the expandable body, so as to jointly make the expandable body have a certain mechanical strength with the carbonization effect generated by acrylamide, pentaerythritol and melamine, and further prevent the expandable body from falling off.

[0019] Combined with the first aspect, the thicknesses of the first coating and the second coating are both 0.2 - 5 mm. In practical applications, the thicknesses of the first coating and the second coating can be arbitrarily selected between 0.2 - 5 mm according to the actual application scenario. For example, the thickness of the first coating is 0.2 - 3 mm, and the thickness of the second coating is 2 - 4 mm; or the thickness of the first coating is 3.5 - 4.5 mm, and the thickness of the second coating is 0.5 - 3 mm.

[0020] Combined with the first aspect, the particle size of the expanded graphite is 30 - 1000 mesh, and the expansion ratio is 50 - 500 times.

[0021] In combination with the first aspect, the high-temperature resistant fiber base cloth is selected from at least one of ceramic fiber fireproof cloth, fiberglass cloth, high-silica cloth, and basalt fiber cloth. The high-temperature resistant fiber base cloth selected in the present invention has the characteristics of being not easily combustible, with an oxygen index ≥ 40%, good thermal stability, a long-term heat resistance ≥ 400 °C, high tensile strength, good toughness, and good surface adhesion, enabling the coating to adhere more firmly to the surface of the base cloth.

[0022] In combination with the first aspect, 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 .

[0023] The second aspect of the present invention provides a preparation method for the above-mentioned fireproof and flame-retardant coated silicon-based cladding material, and the steps include: adding one of the glass powder or glass microbeads, alumina, and calcium aluminate into the silica gel according to a preset ratio, and at the same time, colorants and fillers can be added as needed, stirring to make them uniformly dispersed in the silica gel matrix, adding a curing agent and stirring evenly to obtain the first coating; adding expanded graphite, a curing material, and ammonium molybdate into the silica gel or polyurea or polyurethane according to a preset ratio, and at the same time, colorants and fillers can be added as needed, stirring to make them uniformly dispersed in the silica gel or polyurea or polyurethane, adding a curing agent and stirring evenly to obtain the second coating; respectively coating the first coating and the second coating on both side surfaces of the high-temperature resistant fiber base cloth, and obtaining the fireproof and flame-retardant coated silicon-based cladding material after the coating is cured.

[0024] In combination with the second aspect, the curing agent used can be adaptively selected according to the different types of matrices.

[0025] In combination with the second aspect, the first coating and the second coating are respectively coated on both side surfaces of the high-temperature resistant fiber base cloth by means of roll coating, knife coating, brush coating, or roll pressing to obtain a first coating and a second coating respectively.

[0026] The third aspect of the present invention provides an application of the above-mentioned fireproof and flame-retardant coated silicon-based cladding material in the fire protection of steel cables, the fire protection of cable trays, the fire protection of steel structures, the fire protection of aluminum alloy structures, the fire protection of concrete structures, the flame retardant and fire protection of wooden structures, fireproof plugging, the fire protection of lithium batteries, the fire protection of new energy vehicles, and the fire protection of energy storage facilities. Specifically: the fireproof and flame-retardant coated silicon-based cladding material is used to wrap the object to be fire protected by means of bundling and fixing, Velcro fixing, button fixing, or mechanical fixing.

[0027] The present invention has developed a flexible high-performance fireproof and flame-retardant material. In addition to being applied in the field of cable fire protection, this material can also be applied to fields such as building fire separation, fireproof plugging of holes in power facilities, and fire separation of new energy vehicles and facilities, which require fire zoning and fire separation.

[0028] Preferably, for the bundling and fixing method, metal material straps such as stainless steel or non-metal material straps such as high-temperature resistant fibers can be used to bundle the composite fireproof material cladding on the surface of the object to be fireproof protected. For the Velcro fixing method, the composite fireproof material with an appropriate width can be cut according to the engineering requirements, and the A and B sides of the flame-retardant Velcro are respectively sewn at both ends of the composite fireproof material with high-temperature resistant threads, and an enclosing structure for the protected object is formed through the Velcro. For the button fixing method, the composite fireproof material with an appropriate width is cut according to the engineering requirements, and both ends are fixed through buttons (such as disc buttons, snap buttons, etc.) to form an enclosing structure for the protected object. For the mechanical fixing method, the composite fireproof material with an appropriate width is cut according to the engineering requirements, and the composite fireproof material is directly fixed on the surface of the protected object through mechanical fixing methods such as pressing strips and screws.

[0029] Combined with the third aspect, when performing the cladding, the cladding direction is: the second coating of the cladding material is close to the object to be fireproof protected, and the first coating is away from the object to be fireproof protected, that is, the second coating directly faces inwards and directly contacts the object to be clad, and the first coating faces outwards and contacts the fire source or smoke.

[0030] The beneficial effects of the present invention: Through the specific selection of the coating components and the combination with a high-adhesion high-temperature resistant fiber base cloth, the present invention obtains a coated silicon-based cladding material that simultaneously has fireproof and flame-retardant functions. The smoke toxicity of this cladding material can reach ZA1 level, and the optimal smoke density grade is SDR≤3. It is not easy to burn, has low smoke toxicity, and extremely low smoke production in a fire, and at the same time has excellent weather resistance and environmental adaptability; at the same time, this cladding material also has excellent insulation performance, with a withstand voltage ≥1 kV, and live construction can be carried out when the voltage meets the conditions, which is very suitable for the fireproof upgrade and transformation projects of existing projects. After the cladding material is clad on the object to be protected, such as the surface of a base cable, the flame-retardant grade is significantly improved compared with before cladding (from B3 level to B1 level), the fireproof time is significantly extended (from 6 minutes of the base cable to continuously fireproof for 105 minutes), and the fireproof limit is at least 125 minutes. In addition, this cladding material can not only be used for the flame retardancy and fireproof protection of cables in new projects, but also for the fireproof upgrade of existing projects or flexible fire partitions in new energy scenarios, etc., and has broad application prospects. Description of the Drawings

[0031] Figure 1 It is a photo of the physical object of the fireproof and flame-retardant coated silicon-based cladding material obtained in Example 1 of the present invention; Figure 2 It is a photo of the physical object of the fireproof and flame-retardant coated silicon-based cladding material obtained in Example 2 of the present invention; Figure 3This is a photo of the physical object of the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 3 of the present invention; Figure 4 This is a photo of the physical object of the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 4 of the present invention; Figure 5 This is a on-site photo at the ignition moment when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 1 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 6 This is a on-site photo at the fire resistance limit moment (191 min) when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 1 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 7 This is a photo of the monitoring equipment at the fire resistance limit moment (191 min) when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 1 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 8 This is a on-site photo at the ignition moment when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 2 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 9 This is a on-site photo at the fire resistance limit moment (188 min) when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 2 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 10 This is a photo of the monitoring equipment at the fire resistance limit moment (188 min) when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 2 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 11 This is a on-site photo at the ignition moment when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 3 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 12 This is a on-site photo at the fire resistance limit moment (128 min) when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 3 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 13 This is a photo of the monitoring equipment at the fire resistance limit moment (128 min) when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 3 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 14 This is a on-site photo at the ignition moment when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 4 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 15The on-site photo at the fire resistance limit moment (133 min) when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 4 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out; Figure 16 The photo of the monitoring equipment at the fire resistance limit moment (133 min) when the fire-resistant and flame-retardant coated silicon-based cladding material obtained in Example 4 of the present invention is coated on the surface of a substrate cable and a fire resistance test is carried out. Detailed implementation manners

[0032] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be 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 used to limit the present invention.

[0033] Those skilled in the art of the present technology can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of those of ordinary skill in the art in the field to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and will not be interpreted with an idealized or overly formal meaning unless specifically defined.

[0034] Currently, products for cable fire protection cannot simultaneously take into account both flame retardancy and fire resistance functions, and it is difficult to ensure the consistency of product quality. The flame retardant effect of fireproof coatings is easily affected by construction quality and environmental factors, and the coating is prone to cracking and peeling, with a relatively short actual service life. Moreover, the compatibility of coatings of different batches or formulations is poor, resulting in difficulties in live working when repairing the coating or improving the fire protection level, and it is necessary to replace the cable or shut down the operation; existing flame retardant / fire resistant materials (such as cable bodies or coatings) are not recyclable, which does not conform to the concept of circular economy; in addition, existing flame retardant or fire resistant materials mostly use organic substances as carriers, with the disadvantages of large smoke generation and high toxicity during combustion, which is prone to cause asphyxiation of personnel in a fire and serious secondary hazards; and current fireproof materials cannot protect cables from high temperature loss, with a relatively high cost for post-disaster repair, and lack an "active" fire extinguishing function, and cannot effectively suppress the spread of fire.

[0035] Currently, existing "cable flame retardant tapes" mainly select substrates such as PVC, EVA or ethylene propylene diene monomer rubber, with relatively high smoke toxicity and large smoke generation; and they can only be used for cable flame retardancy and cannot achieve cable fire protection. At the same time, they require winding construction, with a relatively high risk of live working, and it is difficult to move cables for existing projects.

[0036] In view of this, the present invention provides a fire-resistant and flame-retardant coated silicon-based cladding material, which has both flame-retardant and fire-resistant functions, has the advantages of high oxygen index, low smoke production, and low smoke toxicity, and also has excellent weather resistance and insulation performance. It can upgrade other objects such as cables without fire protection functions to a higher flame-retardant grade and fire-resistant grade, and at the same time has a great cost advantage. Moreover, for cables with existing fireproof coatings, this cladding material will not be incompatible with the existing coatings, and is very suitable for the fireproof upgrading and renovation projects of existing projects.

[0037] Unless otherwise specified, the chemical reagents, raw materials, and mechanical equipment used in the following examples and comparative examples are all conventional commercially available products.

[0038] Example 1 This example provides a fire-resistant and flame-retardant coated silicon-based cladding material, which includes a ceramic fiber fireproof cloth (thickness 0.5 - 1 mm) and a first coating and a second coating coated on both surfaces of the ceramic fiber fireproof cloth. Among them, the raw materials of the first coating include 45 wt% silica gel, 30 wt% alumina, 23 wt% glass powder, 1.7 wt% calcium aluminate, and 0.3 wt% curing agent. The raw materials of the second coating include 40 wt% addition-cured silicone rubber, 40 wt% expanded graphite (particle size 100 mesh, expansion ratio 50 times), 18 wt% curing material, 1.8 wt% ammonium molybdate, and 0.2 wt% curing agent. The curing material includes acrylamide, pentaerythritol, melamine, alumina, and zinc borate (the weight ratios in the second coating are 5 wt%, 5 wt%, 3 wt%, 2 wt%, and 3 wt% in sequence).

[0039] The physical picture of this cladding material is as Figure 1 shown.

[0040] Example 2 This example provides a fire-resistant and flame-retardant coated silicon-based cladding material, which includes a glass fiber cloth (thickness 1 - 3 mm) and a first coating and a second coating coated on both surfaces of the glass fiber cloth. Among them, the raw materials of the first coating include 30 wt% silica gel, 40 wt% alumina, 26 wt% glass powder, 1 wt% calcium aluminate, and 3 wt% curing agent. The raw materials of the second coating include 25 wt% condensation-cured silicone rubber, 63 wt% expanded graphite (particle size 50 mesh, expansion ratio 200 times), 9 wt% curing material, 1 wt% ammonium molybdate, and 2 wt% curing agent. The curing material includes acrylamide, pentaerythritol, melamine, and alumina (the weight ratios in the second coating are 5 wt%, 2 wt%, 1 wt%, and 1 wt% in sequence).

[0041] The physical picture of this cladding material is as Figure 2 shown.

[0042] Example 3 This example provides a fire-resistant and flame-retardant coated silicon-based cladding material. The cladding material includes basalt fiber cloth (with a thickness of 3 - 5 mm) and a first coating and a second coating applied to both surfaces of the basalt fiber cloth. Among them, the raw materials of the first coating include 60 wt% silica gel, 21 wt% alumina, 15.5 wt% glass microspheres, 1.5 wt% calcium aluminate, and 2 wt% curing agent. The raw materials of the second coating include 48.5 wt% polyurethane, 15 wt% expanded graphite (with a particle size of 100 mesh and an expansion ratio of 50 times), 33 wt% curing material, 2 wt% ammonium molybdate, and 1.5 wt% curing agent. The curing material includes acrylamide, pentaerythritol, melamine, alumina, and zinc borate (with weight ratios in the second coating being 5 wt%, 10 wt%, 8 wt%, 3 wt%, and 7 wt% respectively).

[0043] The physical picture of this cladding material is as Figure 3 shown.

[0044] Example 4 This example provides a fire-resistant and flame-retardant coated silicon-based cladding material. The cladding material includes high-silica cloth (with a thickness of 2 - 4 mm) and a first coating and a second coating applied to both surfaces of the high-silica cloth. Among them, the raw materials of the first coating include 50 wt% silica gel, 20 wt% alumina, 28 wt% glass microspheres, 1 wt% calcium aluminate, and 1 wt% curing agent. The raw materials of the second coating include 20 wt% polyurea coating (containing silicon oxide filler in the composition), 65.5 wt% expanded graphite (with a particle size of 30 mesh and an expansion ratio of 500 times), 10 wt% curing material, 2 wt% ammonium molybdate, and 2.5 wt% curing agent. The curing material includes acrylamide, pentaerythritol, melamine, and zinc borate (with weight ratios in the second coating being 4 wt%, 2 wt%, 2 wt%, and 2 wt% respectively).

[0045] The physical picture of this cladding material is as Figure 4 shown.

[0046] Example 5 This example provides a preparation method of a fire-resistant and flame-retardant coated silicon-based cladding material with a formula as in Example 1. The steps include: S1. Stretching of the high-temperature resistant fiber base cloth before coating: Lay the ceramic fiber fireproof cloth flat on the coating platform (for the base cloth in roll form, one end can be fixed at the feeding port, and a certain reverse torque can be applied to the roll to stretch the base cloth into a flat surface).

[0047] S2. Prepare the coating: Add alumina, glass powder, and calcium aluminate into the silicone matrix, stir well to ensure that each raw material is evenly distributed in the silicone, add a curing agent and stir evenly to obtain the first coating; Add expanded graphite, curing material, and ammonium molybdate into the silicone matrix, stir well to ensure that each raw material is evenly distributed in the silicone, add a curing agent and stir evenly to obtain the second coating.

[0048] S3. Coat the layer: Apply the first coating and the second coating obtained in step S2 evenly on both sides of the ceramic fiber fireproof cloth by roll coating successively, let it stand naturally, so that the coating fully reacts and cures on the ceramic fiber fireproof cloth, and the fireproof and flame-retardant coated silicone-based coating material is obtained after drying.

[0049] Example 6 This example provides a preparation method of a fireproof and flame-retardant coated silicone-based coating material with a formula as in Example 2. The steps include: S1. Stretch the high-temperature resistant fiber base cloth before coating: Lay the fiberglass cloth flat on the coating platform (for the base cloth in roll form, one end can be fixed at the feeding port, and a certain reverse torque is applied to the roll to stretch the base cloth into a flat surface).

[0050] S2. Prepare the coating: Add alumina, glass powder, and calcium aluminate into the silicone matrix, stir well to ensure that each raw material is evenly distributed in the silicone, add a curing agent and stir evenly to obtain the first coating; Add expanded graphite, curing material, and ammonium molybdate into the silicone matrix, stir well to ensure that each raw material is evenly distributed in the silicone, add a curing agent and stir evenly to obtain the second coating.

[0051] S3. Coat the layer: Apply the first coating and the second coating obtained in step S2 evenly on both sides of the fiberglass cloth by brushing successively, let it stand naturally, so that the coating fully reacts and cures on the fiberglass cloth, and the fireproof and flame-retardant coated silicone-based coating material is obtained after drying.

[0052] Example 7 This example provides a preparation method of a fireproof and flame-retardant coated silicone-based coating material with a formula as in Example 3. The steps include: S1. Stretch the high-temperature resistant fiber base cloth before coating: Lay the basalt fiber cloth flat on the coating platform (for the base cloth in roll form, one end can be fixed at the feeding port, and a certain reverse torque is applied to the roll to stretch the base cloth into a flat surface).

[0053] S2. Preparation of coatings: Alumina, glass microspheres, and calcium aluminate are added to the silicone matrix, and stirred thoroughly to ensure that all raw materials are evenly distributed in the silicone. A curing agent is added and stirred evenly to obtain the first coating; expanded graphite, curing materials, and ammonium molybdate are added to the polyurethane matrix, and stirred thoroughly to ensure that all raw materials are evenly distributed in the polyurethane. A curing agent is added and stirred evenly to obtain the second coating.

[0054] S3. Coating application: The first coating and the second coating obtained in step S2 are successively and evenly applied to both sides of the basalt fiber cloth by scraping, and left to stand naturally to allow the coatings to fully react and cure on the basalt fiber cloth. After drying, a fire-resistant and flame-retardant coated silicon-based cladding material is obtained.

[0055] Example 8 This example provides a method for preparing a fire-resistant and flame-retardant coated silicon-based cladding material with a formulation as in Example 4. The steps include: S1. Pre-extension of the high-temperature resistant fiber base cloth before coating: The high-silica cloth is laid flat on the coating platform (for a roll-mounted base cloth, one end can be fixed at the feeding port, and a certain reverse torque is applied to the roll to stretch the base cloth into a flat surface).

[0056] S2. Preparation of coatings: Alumina, glass microspheres, and calcium aluminate are added to the silicone matrix, and stirred thoroughly to ensure that all raw materials are evenly distributed in the silicone. A curing agent is added and stirred evenly to obtain the first coating; expanded graphite, curing materials, and ammonium molybdate are added to the polyurea coating matrix, and stirred thoroughly to ensure that all raw materials are evenly distributed in the polyurea coating matrix. A curing agent is added and stirred evenly to obtain the second coating.

[0057] S3. Coating application: The first coating and the second coating obtained in step S2 are successively and evenly applied to both sides of the high-silica cloth by roll pressing, and left to stand naturally to allow the coatings to fully react and cure on the high-silica cloth. After drying, a fire-resistant and flame-retardant coated silicon-based cladding material is obtained.

[0058] Comparative Example 1 This comparative example provides a fire-resistant and flame-retardant coated silicon-based cladding material. The composition of this cladding material is basically similar to that of Example 1, except that the first coating does not contain calcium aluminate but is replaced with an equal amount of glass powder, and the composition of the remaining raw materials is the same as that of Example 1. The preparation method is similar to that of Example 4, except that calcium aluminate is replaced with an equal amount of glass powder when preparing the first coating.

[0059] Comparative Example 2 This comparative example provides a fire-resistant and flame-retardant coated silicon-based cladding material. The composition of this cladding material is basically similar to that of Example 1, except that the second coating does not contain ammonium molybdate, but is replaced with an equal amount of expanded graphite. 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, except that ammonium molybdate is replaced with an equal amount of expanded graphite when preparing the second coating.

[0060] Comparative Example 3 This comparative example provides a fire-resistant and flame-retardant coated silicon-based cladding material. The composition of this cladding 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 with an equal amount of pentaerythritol. 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, except that melamine is replaced with an equal amount of pentaerythritol when preparing the second coating.

[0061] Comparative Example 4 This comparative example provides a cable with a fireproof coating on its surface. 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. The components of the fireproof coating applied on the surface of this base cable include 10wt% - 40wt% ammonium polyphosphate, 5wt% - 20wt% melamine, 2wt% - 12wt% pentaerythritol, and 10wt% - 30wt% acrylic emulsion, and the balance is a mixed solution of ethanol and water. The coating thickness is 1mm.

[0062] Comparative Example 5 This comparative example provides a cable sleeved with a protective sleeve. 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. The material of the used protective sleeve is glass fiber with a silicone coating on the surface and a ceramic fiber cloth lining, and the thickness is 3 - 4mm.

[0063] Inspection Example The cladding materials obtained in Examples 1 - 4 and Comparative Examples 1 - 3 were respectively bundled and coated on the surface of a cross-linked polyethylene insulated polyethylene sheathed power cable YJV22 - 0.6 / 1kV - 3*50 + 1*25 without flame-retardant function, which is commonly used in engineering, using cable ties made of high-temperature resistant fiber materials, and the fire resistance and flame retardancy were actually 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 - 5 were tested.

[0064] Among them, the flame retardant grades of the cable before and after coating are tested according to GB 31247-2014 "Classification of the burning performance of cables and optical cables"; the fire resistance grades of the cable before and after coating are tested according to GB / T 19216.21-2003 "Circuit integrity test of cables or optical cables under fire conditions - Part 21: Test procedures and requirements - Cables with rated voltage 0.6 / 1.0 kV and below"; the weather resistance test 1 includes corrosiveness, water resistance, oil resistance, acid resistance, water resistance, damp heat resistance, freeze-thaw cycle test carried out according to GB 23864-2023 "Fireproof sealing materials"; the weather resistance test 2 includes heat resistance to exposure, damp heat resistance, freeze-thaw cycle resistance, acid resistance, alkali resistance, salt spray corrosion resistance, ultraviolet radiation resistance carried out according to GB 14907-2018 "Fireproof coatings for steel structures"; oil resistance, brine resistance, damp heat resistance, freeze-thaw cycle test are carried out according to GB 28374-2012 "Cable fireproof coatings", the smoke toxicity of the material is tested according to GB / T 20285-2006 "Hazard classification of smoke toxicity of materials", the oxygen index of the material is tested according to GB / T 2406.2-2009 "Plastics - Determination of burning behavior by the oxygen index method - Part 2: Room temperature test", the smoke density grade of the material is tested according to GB / T 20284-2006 "Single burning test of building materials or products", and the insulation performance of the material is tested with a multimeter. The test results are shown in Table 1.

[0065] Table 1

[0066] As can be seen from Table 1, compared with the non-fire-resistant base cable, 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 requirement that the fire-resistant cable remains energized for 90 minutes + 15 minutes of fire outage, and the fire resistance limits all exceed 125 minutes; the flame retardant performance is improved from Class B3 to Class B1; while the fire resistance and flame retardant performance of the coating material are significantly improved, its weather resistance and actual withstand voltage are basically not reduced compared with the base cable, while the smoke density is significantly reduced and the safety grade of smoke toxicity is significantly improved. It can be seen that after the non-fire-resistant base cable is coated and protected with the coating material provided in the embodiments of the present invention, the fire-related performances such as the fire resistance performance, flame retardant performance, smoke toxicity, and smoke density grade of the obtained coating material-cable combination structure are all significantly and beneficially improved.

[0067] Comparing Example 1 with Comparative Examples 1 to 3, it can be seen that after adjusting the formulations of the first coating or the second coating, the synergistic effect between the active ingredients is weakened to varying degrees, and the indicators such as the fire resistance, flame retardancy, smoke toxicity or smoke density grade of the combined structure after the coated material coats the base material cable deteriorate to varying degrees. This shows that there is a specific mutual synergistic effect between the components of the present invention, thus forming a stable heat insulation protection layer, realizing the protection of the base material cable under combustion conditions, and at the same time having important significance for suppressing the occurrence of adverse situations such as smoke and toxicity during the combustion process.

[0068] Comparing Examples 1 to 4 with Comparative Example 4, which is a common cable fire protection method at present - coating a cable fire protection paint on the surface of the base material cable, it can be seen that in addition to solving the problems of difficult construction of the cable fire protection paint and inability to work live, the present invention also solves the problem of poor weather resistance of the cable fire protection paint. At the same time, the present invention has a greater improvement than Comparative Example 4 in terms of fire resistance limit, smoke toxicity and smoke density grade.

[0069] Comparing Examples 1 to 4 with Comparative Example 5, which is a common cable protection and fire prevention method at present - covering a cable protection sleeve on the outer surface of the base material cable, it can be seen that the flame retardancy of Comparative Example 5 is poorer than that of the present invention. At the same time, although the fire resistance limit is improved compared with the base material cable, it still cannot meet the performance indicators of fire-resistant cables, and there is a large gap in fire resistance and flame retardancy compared with the present invention.

[0070] Among the embodiments of the present invention, due to the different types of the gluing matrix of the second coating, there are also differences in terms of fire resistance and other aspects. Among them, in Examples 1 and 2, silica gel is used as the main binder, which is a silicon-based organic compound, and its flame retardancy is better than that of the carbon-based organic compounds polyurethane and polyurea. Therefore, its fire resistance limit is much better than that of Example 3 with a polyurethane binder as the main body of the second coating and Example 4 with a polyurea binder as the main body of the second coating. Similarly, the smoke density grade indicators of Examples 1 and 2 are also significantly better than those of Examples 3 and 4. During the fire resistance test, local visible flame combustion phenomena occurred in Examples 3 and 4. However, upon observation, the combustion focused on the gaps of the formed coating structure, and the combustion process did not affect the protection effect of the coating material on the internal base material cable. For Example 3, since the molecular structure of polyurethane will be damaged by ultraviolet radiation, although it meets the weather resistance test 1 in the cable application field, in the fire-resistant test 2 with ultraviolet radiation and the evaluation indicators of outdoor steel structure fire protection coatings, the ultraviolet attenuation is relatively obvious. Nevertheless, since the second coating containing polyurethane faces the cable and is not affected by ultraviolet radiation during daily use, it does not affect its actual use effect.

[0071] Moreover, the coating material provided by the present invention has good insulation performance, with a withstand voltage ≥ 1 kV, and can be applied for construction coating under the energized state of the base cable, which is of great significance for the fire prevention renovation of existing projects.

[0072] In addition, Figures 5 to 16 The following are the on-site photos at different times during the fire resistance performance test and the on-site photos of the monitoring equipment. It can be seen that when the coating materials obtained from Examples 1 to 4 provided by the present invention are coated on the base cable and the fire resistance performance test is carried out, large-scale self-combustion of the coating material does not occur during the fire resistance test. Although local open flames appear in Examples 3 to 4, they are actually the combustion at the gaps of the coating structure and do not affect the protected objects inside the coating structure. And during the fire resistance test, through the monitoring of the monitoring equipment (in sequence Figure 7 , Figure 10 , Figure 13 and Figure 16 ), the base cable protected by the coating material can always maintain the energized state (the full brightness of the 4 red light bulbs in the top row represents that the cable still maintains the energized state), indicating that after the non-fire-resistant base cable is coated with the coating material, even in case of a fire, the base cable can maintain the normal working state for a long time, reducing the losses caused by power failure due to the fire.

[0073] The above is only the preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and all should be covered within the protection scope of the present invention.

Claims

1. A refractory and flame-retardant coated silicon-based cladding material, characterized in that, The coated silicon-based coating material includes a high-temperature resistant fiber base cloth, and a first coating and a second coating coated on both surfaces of the high-temperature resistant fiber base cloth; Among them, the raw materials of the first coating include 30wt% - 60wt% of silica gel, 20wt% - 40wt% of alumina, 15wt% - 30wt% of glass powder or glass microspheres, 1wt% - 2wt% of calcium aluminate, and 0.3wt% - 3wt% of 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 curing material, 1wt% - 2wt% of ammonium molybdate, and 0.2wt% - 2.5wt% of curing agent, and the curing material includes acrylamide, pentaerythritol, and melamine.

2. The fire-resistant and flame-retardant coated silicon-based cladding material according to claim 1, characterized in that, The curing material also includes at least one of alumina and zinc borate.

3. The fireproof and flame-retardant coating type silicon-based coating material according to claim 1, characterized in that, The thicknesses of the first coating and the second coating are both 0.2 - 5mm.

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 mesh, and the expansion ratio is 50 - 500 times.

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

6. The fire-resistant and flame-retardant coating type 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 preparation method of the fire-resistant and flame-retardant coated silicon-based cladding material according to any one of claims 1 to 6, characterized in that the steps Including: Adding one of the glass powder or glass microspheres, alumina, and calcium aluminate into the silica gel according to a preset ratio, and stirring until evenly dispersed to obtain a first coating material; Adding the expanded graphite, curing material, and ammonium molybdate into the silica gel or polyurea or polyurethane according to a preset ratio, and stirring until evenly dispersed to obtain a second coating material; Coating the first coating material and the second coating material on both surfaces of the high-temperature resistant fiber base cloth respectively, and obtaining the fireproof and flame-retardant coated silicon-based coating material after the coating materials are cured.

8. The preparation method of the refractory and flame-retardant coated silicon-based coating material according to claim 7, characterized in that, Coating the first coating material and the second coating material on both surfaces of the high-temperature resistant fiber base cloth respectively by means of roll coating, scraping coating, brush coating, or roll pressing.

9. Use of the refractory and flame-retardant coated silicon-based cladding material according to any one of claims 1 to 6 in fire protection of steel cables, fire protection of cable trays, 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, Coating the object to be fireproof protected with the fireproof and flame-retardant coated silicon-based coating material by means of bundling and fixing, Velcro fixing, button fixing, or mechanical fixing.

10. The application according to claim 9, wherein When performing the coating, the coating direction is: the second coating of the coating material is close to the object to be fireproof protected, and the first coating is far from the object to be fireproof protected.

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