Preparation method of low-permeability lightweight flexible fireproof material

Abstract

The present invention provides a method for preparing a low-permeability, lightweight, flexible fireproof material, which relates to the field of fireproof materials and includes: step S1, preparing a mixed mesh with different surface densities; step S2, forming a mixed layer with the mixed mesh and an inorganic fiber reinforcement, and performing non-linear phase needle punching on the mixed layer to prepare an intermediate layer; step S3, subjecting the intermediate layer to low-temperature, low-pressure molding and compounding; step S4, arranging an outer layer and an inner layer, and performing layer laying and sewing to obtain a low-permeability, lightweight, flexible fireproof material. The fireproof material prepared by this method has excellent fireproofing properties and does not generate smoke or gas during combustion. At the same time, the fireproof material combines the characteristics of low permeability, good flexibility, and low density, and is easy to combine with other structural components, which can greatly reduce the overall weight of the firewall structure.

Description

Technical Field

[0001] The invention relates to the technical field of fireproof materials, and in particular to a method for preparing a low-air-permeability, lightweight, flexible fireproof material. Background Art

[0002] With the rapid development of high-performance aircraft, the operating gas temperature of aircraft power units has greatly increased, making the environment around the power units increasingly harsh. To ensure the normal use of functional areas such as the power unit, a firewall structure is usually installed between the power unit and the passenger compartment or other functional areas. Traditional firewall structures mainly include metal material structures formed by stainless steel and titanium alloys, ablative fiber-reinforced composite materials, metal + ablative coatings, etc. However, typical firewall structures composed of metal materials have problems such as heavy weight and easy heat conduction. New fiber-reinforced resin-based composite materials have problems such as difficulty in providing long-term effective protection and will produce smoke and gas. Firewall structures composed of metal + ablative coatings have complex manufacturing processes and problems such as smoke and slag when the coating absorpts, which is not conducive to the subsequent cleaning and replacement of the firewall structure.

[0003] In addition, with the popularization of the demand for lightweight materials, when installing fireproof materials on future new energy-powered aircraft (such as flying cars), in addition to meeting the requirements of effectively preventing fire within a certain period of time and achieving the thermal insulation protection function of functional areas, the overall weight of the fireproof materials also needs to be limited to meet the overall lightweight requirements of the aircraft. Summary of the Invention

[0004] In response to the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a method for preparing a low-permeability, lightweight, flexible fireproof material. The fireproof material prepared by this method has excellent fire-resistant performance, does not produce smoke or gas during the burning process, and is more environmentally friendly and safe. At the same time, the fireproof material prepared by this method has the characteristics of low permeability, good flexibility, and low density. It is easy to be combined with other structural parts in a flexible manner, and can greatly reduce the overall weight of the firewall structure.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A method for preparing a low-permeability, lightweight, flexible fireproof material, comprising:

[0007] Step S1, preparing a mixed web with different surface densities by needle punching inorganic chopped fiber yarn;

[0008] Step S2: First, the mixed web is stacked and laid in layers according to the surface density from high to low. During the stacking process, inorganic fiber reinforcements are inserted between the layers of the mixed web and the inorganic fiber reinforcements are evenly distributed between the layers of the mixed web to form a mixed layer; then, the mixed layer is subjected to non-linear phase needle punching to form an intermediate layer;

[0009] Step S3, performing low-temperature and low-pressure molding and compounding on the middle layer;

[0010] Step S4: an outer layer and an inner layer are respectively arranged on both sides of the molded composite middle layer, and the layers are laid and sewn to obtain a low-permeability, lightweight, flexible fireproof material.

[0011] Based on further optimization of the above scheme, the inorganic chopped fiber yarn includes quartz fiber, basalt fiber and mixed fiber, wherein the fiber diameter is 4 to 9 μm and the fiber length is 50 to 80 mm; at the same time, the mass of quartz fiber and basalt fiber accounts for 80% to 92% of the total mass of the mixed web, and the rest is mixed fiber, wherein the mass of basalt fiber accounts for 20% to 65% of the total mass of the mixed web, and the mass of quartz fiber accounts for 25% to 72% of the total mass of the mixed web.

[0012] Based on further optimization of the above solution, the hybrid fiber adopts one or more of silicon carbide fiber, alumina fiber and mullite fiber.

[0013] Based on the further optimization of the above scheme, the surface density of the mixed web is in the range of 10 to 80 g / m 2 By adjusting the content of basalt fiber and quartz fiber, the preparation of mixed mesh with different surface densities can be achieved.

[0014] Based on the further optimization of the above scheme, the inorganic fiber reinforcement adopts either inorganic fiber continuous yarn or mesh cloth; if the inorganic fiber reinforcement adopts inorganic fiber continuous yarn, a 0° / 90° laying structure is adopted, and the laying distance between adjacent yarns is 5 to 28 mm; if the inorganic fiber reinforcement adopts mesh cloth, its surface density is 40 to 88 g / m 2 .

[0015] Preferably, if the inorganic fiber reinforcement is a mesh cloth, its surface density is 44 g / m 2 , 54 g / m 2 , 64 g / m 2 , 74g / m 2 , 84 g / m 2 Any of .

[0016] Based on further optimization of the above solution, the material of the inorganic fiber reinforcement is woven from one or both of quartz fiber and basalt fiber.

[0017] Based on further optimization of the above scheme, the needling angle of the non-illegal phase needling (i.e. the angle formed by the needling direction and the normal phase) is 15°~40°, and the needling direction of the non-illegal phase needling is from the high-density side to the low-density side of the mixed layer.

[0018] The use of illegal phase needling can, firstly, extend the heat transfer path in the middle layer, thereby reducing the heat transfer efficiency in the thickness direction of the middle layer; secondly, dissipate the heat transferred perpendicular to the thickness direction of the middle layer layer by layer, thereby effectively improving the fire prevention and heat insulation effect of the middle layer.

[0019] Based on the further optimization of the above scheme, the relationship between the surface density of the middle layer, the number of mixed mesh layers, the number of inorganic fiber reinforcement layers, and the needle density is as follows: when the surface density of the middle layer is not greater than 280g / m 2 The number of mixed web layers is 3 to 28, the inorganic fiber reinforcement uses inorganic fiber continuous yarn, the number of layers is 1 to 5 and is evenly distributed between the mixed webs (that is, the number of layers of the inorganic fiber reinforcement is less than the number of layers of the mixed web), and the needle density is 33 to 65 needles / cm 2 ; When the surface density of the middle layer is greater than 280 g / m 2 And not more than 450 g / m 2 The number of layers of the mixed web is 5 to 45, the inorganic fiber reinforcement is either inorganic fiber continuous yarn or mesh cloth, the number of layers of the inorganic fiber continuous yarn is 3 to 8 or the number of layers of the mesh cloth is 1 to 5 and is evenly distributed between the mixed webs (i.e., the number of layers of the inorganic fiber reinforcement is less than the number of layers of the mixed web), and the needle density is 55 to 95 needles / cm 2 ; When the surface density of the middle layer is greater than 450 g / m 2 and not more than 780 g / m 2 The number of layers of the mixed web is 9 to 60, the inorganic fiber reinforcement is either inorganic fiber continuous yarn or mesh cloth, the number of layers of the inorganic fiber continuous yarn is 7 to 16 or the number of layers of the mesh cloth is 5 to 10 and is evenly distributed between the mixed webs (i.e., the number of layers of the inorganic fiber reinforcement is less than the number of layers of the mixed web), and the needle punching density is 85 to 105 needles / cm 2 .

[0020] Based on further optimization of the above scheme, the temperature of the low-temperature and low-pressure molding compound is 150-220°C, the pressure is 0.04-0.1 MPa, and the time is 6-24 hours.

[0021] Low temperature and low pressure molding is used to compress the middle layer formed by the stacking of mixed mesh and inorganic fiber reinforcement through illegal phase needle punching. Firstly, the thickness of the middle layer is effectively squeezed and the volume of the middle layer is reduced to ensure that the overall thickness of the fireproof material is thin and uniform. Secondly, during the compression process, the displacement effect of the fiber is used to seal the puncture holes formed during the puncture process, thereby generating closed puncture cavities to avoid the formation of heat conduction paths in the middle layer, thereby effectively reducing the thermal conductivity and air permeability of the middle layer. At the same time, it is also beneficial for heat to dissipate in the middle layer, avoiding the formation of local temperature concentration, and ensuring the overall fireproof and heat-resistant performance of the middle layer.

[0022] Based on the further optimization of the above scheme, the outer layer and the inner layer are woven by any one of quartz fiber cloth and alumina fiber cloth or a mixture of the two fibers (i.e. quartz fiber and alumina fiber), and the surface density of the outer layer and the inner layer fiber cloth is 70-110g / m 2 The outer layer, middle layer and inner layer are sewn together with high temperature resistant fiber thread.

[0023] The following are the effects of the technical solution of the present invention:

[0024] This application uses inorganic fiber continuous yarn or mesh cloth as a reinforcement for the hybrid web, and combines it with the gradient formed by the stacking of the hybrid web to effectively improve the transverse / longitudinal mechanical properties of the middle layer and reduce the overall density. Secondly, it largely avoids damage to the fiber woven fabric during the needling process. Thirdly, it effectively improves the interlayer bonding strength during the needling process, avoiding the formation of interlayer gaps that lead to temperature convergence and the formation of convergence points. Fourthly, it dissipates the temperature layer by layer, improving the overall fireproof and heat-resistant performance of the middle layer. At the same time, this application further improves the fireproof and heat-resistant performance of the middle layer by combining the non-linear needling method with low-temperature and low-pressure molding of the middle layer formed by the stacked hybrid web and inorganic fiber reinforcement, while sealing the needle holes, thereby preventing air heat convection in the middle layer and reducing the heat transfer efficiency and air permeability of the middle layer along the thickness direction, thereby effectively isolating the high-temperature gas from escaping to the protected surface, and having the effects of low air permeability, light weight, and high-efficiency thermal insulation protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the stacking structure of the middle layer of the fireproof material in an embodiment of the present invention.

[0026] Figure 2 This is a schematic diagram of illegal phase needling of the middle layer of the fireproof material in an embodiment of the present invention.

[0027] Among them, 11. mixed mesh; 12. inorganic fiber reinforcement. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly described below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0029] Example 1:

[0030] A method for preparing a low-permeability, lightweight, flexible fireproof material, comprising:

[0031] Step S1: Needle-punch a mixture of inorganic chopped fiber yarns to form a mixed web 11 with different surface densities. The inorganic chopped fiber yarns include quartz fiber, basalt fiber, and hybrid fiber, with the hybrid fiber being silicon carbide fiber. The fiber diameter (i.e., quartz fiber, basalt fiber, and silicon carbide fiber) is 4 μm and the fiber length is 50 mm. The quartz fiber and basalt fiber account for 80% of the total mass of the mixed web 11, with the remainder being hybrid fiber (i.e., the mass percentage of hybrid fiber-silicon carbide fiber is 20%). The basalt fiber accounts for 20% to 65% of the total mass of the mixed web 11, and the quartz fiber accounts for 25% to 72% of the total mass of the mixed web 11. The surface density of the mixed web 11 ranges from 20 to 30 g / m 2 By adjusting the content of basalt fiber and quartz fiber, the preparation of mixed mesh 11 with different surface densities can be achieved (because the surface density of quartz fiber is lower than that of basalt fiber, the surface density of the mixed mesh 11 can be increased by gradually reducing the content of quartz fiber. During this process, the content of mixed fibers remains unchanged).

[0032] Step S2: First, the mixed web 11 is stacked and laid in layers according to the surface density from high to low (i.e., the basalt fiber content is stacked and laid in layers from high to low). During the stacking process, the inorganic fiber reinforcement 12 is inserted between the layers of the mixed web 11 and the inorganic fiber reinforcement 12 is evenly distributed between the layers of the mixed web 11 to form a mixed layer (for specific structure, see Figure 1 The inorganic fiber reinforcement 12 is made of continuous inorganic fiber yarns, using a 0° / 90° layup structure, with a layup distance of 8 mm between adjacent yarns. The inorganic fiber reinforcement 12 is made of woven quartz fiber.

[0033] Then, the mixed layer is subjected to illegal phase needle punching to form the middle layer; Figure 2 As shown, the puncture angle θ of the non-linear phase puncture (i.e., the angle formed by the puncture direction and the normal phase) is 15°, and the puncture direction of the non-linear phase puncture is from the high-density side to the low-density side of the mixed layer (i.e., Figure 2 from top to bottom as shown).

[0034] The relationship among the surface density of the middle layer, the number of layers of the mixed web 11, the number of layers of the inorganic fiber reinforcement 12, and the needle punching density is as follows: In this embodiment, the total surface density of the middle layer is not more than 280 g / m 2 (ie ≤280g / m 2 ), the mixed web 11 has 6 layers, the inorganic fiber reinforcement 12 uses inorganic fiber continuous yarn, has 2 layers and is evenly distributed between the mixed webs 11 (that is, a layer of inorganic fiber reinforcement 12 is inserted between every two layers of mixed webs 11), and the needle density is 35 needles / cm 2 .

[0035] Step S3, subjecting the intermediate layer to low-temperature and low-pressure molding and compounding; the temperature of the low-temperature and low-pressure molding and compounding is 150° C., the pressure is 0.04 MPa, and the time is 18 hours.

[0036] Step S4: arrange outer layers and inner layers on both sides of the molded composite middle layer, and perform layer sewing to obtain a low-permeability, lightweight, flexible fireproof material; the outer and inner layers are made of quartz fiber cloth, and the surface density of the outer and inner fiber cloths is 70g / m 2 The outer layer, the middle layer and the inner layer are sewn together by high temperature resistant fiber thread (the high temperature resistant fiber thread can be conventional high temperature resistant fiber thread in the art, and is not specifically limited in this embodiment).

[0037] Example 2:

[0038] A method for preparing a low-permeability, lightweight, flexible fireproof material, comprising:

[0039] Step S1: Needle-punch a mixture of inorganic chopped fiber yarns to form a mixed web 11 with different surface densities. The inorganic chopped fiber yarns include quartz fiber, basalt fiber, and hybrid fiber, and the hybrid fiber is a mixture of alumina fiber and mullite fiber. The fiber diameter (i.e., quartz fiber, basalt fiber, and hybrid fiber) is 6μm and the fiber length is 65mm. At the same time, the mass of the quartz fiber and basalt fiber accounts for 86% of the total mass of the mixed web 11, and the remainder is hybrid fiber (i.e., the mass percentage of hybrid fiber is 14%). The mass of basalt fiber accounts for 20% to 65% of the total mass of the mixed web 11, and the mass of quartz fiber accounts for 25% to 72% of the total mass of the mixed web 11. The surface density of the mixed web 11 is 40 to 50g / m 2 By adjusting the content of basalt fiber and quartz fiber, the preparation of mixed mesh 11 with different surface densities can be achieved (because the surface density of quartz fiber is lower than that of basalt fiber, the surface density of the mixed mesh 11 can be increased by gradually reducing the content of quartz fiber. During this process, the content of mixed fibers remains unchanged).

[0040] Step S2: First, the mixed web 11 is stacked and laid in layers according to the surface density from high to low (i.e., the basalt fiber content is stacked and laid in layers from high to low). During the stacking process, the inorganic fiber reinforcement 12 is inserted between the layers of the mixed web 11 and the inorganic fiber reinforcement 12 is evenly distributed between the layers of the mixed web 11 to form a mixed layer (for specific structure, see Figure 1 The inorganic fiber reinforcement 12 is made of mesh cloth with a surface density of 40 to 88 g / m 2 (The surface density of the mesh is preferably 44 g / m 2 , 54 g / m 2 , 64 g / m 2 , 74 g / m 2 , 84 g / m 2 In this embodiment, the surface density of the mesh cloth is preferably 64 g / m 2 The inorganic fiber reinforcement 12 is made of a mixture of quartz fiber and basalt fiber.

[0041] Then, the mixed layer is subjected to illegal phase needle punching to form the middle layer; Figure 2 As shown, the acupuncture angle θ of the non-linear phase acupuncture (i.e., the angle formed by the acupuncture direction and the normal phase) is 30°, and the acupuncture direction of the non-linear phase acupuncture is from the high-density side to the low-density side of the mixed layer (i.e., Figure 2 from top to bottom as shown).

[0042] The relationship among the surface density of the middle layer, the number of layers of the mixed web 11, the number of layers of the inorganic fiber reinforcement 12, and the needle punching density is as follows: In this embodiment, the total surface density of the middle layer is greater than 280 g / m 2 And not more than 450 g / m 2 (i.e. >280 g / m 2 , ≤450 g / m 2 ), the mixed mesh 11 has 16 layers, the inorganic fiber reinforcement 12 is a mesh cloth, which has 3 layers and is evenly distributed between the mixed mesh 11 (that is, a layer of inorganic fiber reinforcement 12 is inserted between every four layers of mixed mesh 11), and the needle density is 65 needles / cm 2 .

[0043] Step S3, subjecting the intermediate layer to low-temperature and low-pressure molding and compounding; the temperature of the low-temperature and low-pressure molding and compounding is 185° C., the pressure is 0.07 MPa, and the time is 15 hours.

[0044] Step S4: Arrange outer layers and inner layers on both sides of the molded composite middle layer, and perform layer sewing to obtain a low-permeability, lightweight, flexible fireproof material; the outer layer and the inner layer are woven from a mixture of quartz fiber and alumina fiber, and the surface density of the outer and inner fiber cloths is 90g / m 2The outer layer, the middle layer and the inner layer are sewn together by high temperature resistant fiber thread (the high temperature resistant fiber thread can be conventional high temperature resistant fiber thread in the art, and is not specifically limited in this embodiment).

[0045] Example 3:

[0046] A method for preparing a low-permeability, lightweight, flexible fireproof material, comprising:

[0047] Step S1: Needle-punch a mixture of inorganic chopped fiber yarns to form a mixed web 11 with different surface densities. The inorganic chopped fiber yarns include quartz fiber, basalt fiber, and hybrid fiber, and the hybrid fiber is mullite fiber. The fiber diameter (i.e., quartz fiber, basalt fiber, and mullite fiber) is 9μm and the fiber length is 80mm. At the same time, the mass of quartz fiber and basalt fiber accounts for 92% of the total mass of the mixed web 11, and the remainder is hybrid fiber (i.e., the mass percentage of hybrid fiber-mullite fiber is 8%). The mass of basalt fiber accounts for 20% to 65% of the total mass of the mixed web 11, and the mass of quartz fiber accounts for 25% to 72% of the total mass of the mixed web 11. The surface density of the mixed web 11 ranges from 60 to 70g / m 2 By adjusting the content of basalt fiber and quartz fiber, the preparation of mixed mesh 11 with different surface densities can be achieved (because the surface density of quartz fiber is lower than that of basalt fiber, the surface density of the mixed mesh 11 can be increased by gradually reducing the content of quartz fiber. During this process, the content of mixed fibers remains unchanged).

[0048] Step S2: First, the mixed web 11 is stacked and laid in layers according to the surface density from high to low (i.e., the basalt fiber content is stacked and laid in layers from high to low). During the stacking process, the inorganic fiber reinforcement 12 is inserted between the layers of the mixed web 11 and the inorganic fiber reinforcement 12 is evenly distributed between the layers of the mixed web 11 to form a mixed layer (for specific structure, see Figure 1 The inorganic fiber reinforcement 12 is made of continuous inorganic fiber yarns, laid out in a 0° / 90° pattern with a 10 mm distance between adjacent yarns. The inorganic fiber reinforcement 12 is woven from basalt fibers.

[0049] Then, the mixed layer is subjected to illegal phase needle punching to form the middle layer; Figure 2 As shown, the puncture angle θ of the non-linear phase puncture (i.e., the angle formed by the puncture direction and the normal phase) is 40°, and the puncture direction of the non-linear phase puncture is from the high-density side to the low-density side of the mixed layer (i.e., Figure 2 from top to bottom as shown).

[0050] The relationship between the surface density of the middle layer, the number of layers of the mixed web 11, the number of layers of the inorganic fiber reinforcement 12, and the needle density is as follows: In this embodiment, the total surface density of the middle layer is greater than 450 g / m 2 and not more than 780 g / m 2 (i.e. >450 g / m 2 、≤780 g / m 2 ), the mixed web 11 has 40 layers, the inorganic fiber reinforcement 12 uses inorganic fiber continuous yarn, and has 9 layers and is evenly distributed between the mixed webs 11 (that is, a layer of inorganic fiber reinforcement 12 is inserted between every four layers of mixed webs 11), and the needle density is 95 needles / cm 2 .

[0051] Step S3, subjecting the intermediate layer to low-temperature and low-pressure molding and compounding; the temperature of the low-temperature and low-pressure molding and compounding is 220° C., the pressure is 0.1 MPa, and the time is 12 hours.

[0052] Step S4: an outer layer and an inner layer are respectively provided on both sides of the molded composite middle layer, and the layers are laid and sewn to obtain a low-permeability, lightweight, flexible fireproof material; the outer layer and the inner layer are woven with alumina fiber cloth, and the surface density of the outer layer and the inner layer fiber cloth is 110g / m 2 The outer layer, the middle layer and the inner layer are sewn together by high temperature resistant fiber thread (the high temperature resistant fiber thread can be conventional high temperature resistant fiber thread in the art, and is not specifically limited in this embodiment).

[0053] Comparative Example 1:

[0054] A method for preparing a fireproof material, comprising:

[0055] Step S1 is completely consistent with step S1 in embodiment 2.

[0056] Step S2: First, the mixed mesh is stacked and laid in layers according to the surface density from high to low (i.e., the basalt fiber content is stacked and laid in layers from high to low). During the stacking process, inorganic fiber reinforcements are inserted between the layers of the mixed mesh and the inorganic fiber reinforcements are evenly distributed between the layers of the mixed mesh to form a mixed layer. The inorganic fiber reinforcement is a mesh cloth with a surface density of 40 to 88 g / m 2 (The surface density of the mesh is preferably 44 g / m 2 , 54 g / m 2 , 64 g / m 2 , 74g / m 2 , 84 g / m 2 In this comparative example, the surface density of the mesh is preferably 64 g / m 2 The inorganic fiber reinforcement is made of a mixture of quartz fiber and basalt fiber.

[0057] Then, the mixed layer is subjected to phase needle punching, that is, the mixed layer is subjected to phase needle punching perpendicular to the surface of the mixed layer (that is, along the thickness direction of the mixed layer) from the high-density layer to the low-density side to form an intermediate layer;

[0058] The relationship between the surface density of the middle layer, the number of mixed mesh layers, the number of inorganic fiber reinforcement layers, and the needle density is as follows: In this comparative example, the total surface density of the middle layer is greater than 280 g / m 2 And not more than 450 g / m 2 (i.e. >280 g / m 2 、≤450 g / m 2 ), the number of mixed mesh layers is 16, the inorganic fiber reinforcement is a mesh cloth, the number of layers is 3 and evenly distributed between the mixed mesh (that is, a layer of inorganic fiber reinforcement is inserted between every four layers of mixed mesh), and the needle density is 65 needles / cm 2 .

[0059] Step S3 is completely consistent with step S3 in embodiment 2.

[0060] Step S4 is completely consistent with step S4 in embodiment 2.

[0061] Comparative Example 2:

[0062] A method for preparing a fireproof material, comprising:

[0063] Step S1 is completely consistent with step S1 in embodiment 2.

[0064] Step S2 is completely consistent with step S2 in embodiment 2.

[0065] Step S3, the middle layer is subjected to molding and compounding; the molding and compounding temperature is 300° C., the pressure is 0.2 MPa, and the time is 15 hours.

[0066] Step S4 is completely consistent with step S4 in embodiment 2.

[0067] Comparative Example 3:

[0068] A method for preparing a fireproof material, comprising:

[0069] Step S1 is completely consistent with step S1 in embodiment 2.

[0070] Step S2: First, the mixed mesh is stacked and laid in layers according to the surface density from high to low (i.e., the basalt fiber content is stacked and laid in layers from high to low). During the stacking process, inorganic fiber reinforcements are inserted between the layers of the mixed mesh to form a mixed layer. The inorganic fiber reinforcement is a mesh cloth with a surface density of 40 to 88 g / m 2 (The surface density of the mesh is preferably 44 g / m2 , 54 g / m 2 , 64 g / m 2 , 74 g / m 2 , 84 g / m 2 In this comparative example, the surface density of the mesh is preferably 64 g / m 2 The inorganic fiber reinforcement is made of a mixture of quartz fiber and basalt fiber.

[0071] Then, the mixed layer is subjected to non-normal phase needling to form an intermediate layer; the needling angle θ of the non-normal phase needling (i.e., the angle formed by the needling direction and the normal phase) is 30°, and the needling direction of the non-normal phase needling is from the high-density side to the low-density side of the mixed layer.

[0072] The relationship between the surface density of the middle layer, the number of mixed mesh layers, the number of inorganic fiber reinforcement layers, and the needle density is as follows: In this comparative example, the total surface density of the middle layer is greater than 280 g / m 2 And not more than 450 g / m 2 (i.e. >280 g / m 2 、≤450 g / m 2 ), the mixed mesh layer has 16 layers, the inorganic fiber reinforcement adopts mesh cloth, the number of layers is 3, and the three layers of inorganic fiber reinforcement are all inserted in the middle of the mixed mesh layer (that is, the 16 layers of mixed mesh are divided into two parts according to every 8 layers, and three layers of inorganic fiber reinforcement are set between the two parts), and the needle density is 65 needles / cm 2 .

[0073] Step S3 is completely consistent with step S3 in embodiment 2.

[0074] Step S4 is completely consistent with step S4 in embodiment 2.

[0075] The fireproof materials obtained in Examples 1 to 3 and Comparative Examples 1 to 3 were respectively tested for fireproof performance (i.e., burning for 20 minutes under a flame of 1150°C, observing the burning situation and testing the cold surface temperature), thermal conductivity (at 25°C), and air permeability under the same conditions (i.e., the same environment, including but not limited to ambient temperature, humidity, etc.). The test results are shown in the following table:

[0076]

[0077] As shown in the table above: The technical means of non-linear needling and low-temperature low-pressure molding and the structure of staggered stacking of mixed mesh and inorganic fiber reinforcement adopted in this application can obtain lower thermal conductivity and air permeability, thereby effectively improving the overall fireproof performance of the fireproof material and isolating high-temperature gas from escaping to the cold surface of the fireproof material.

Claims

1. A method for preparing a low-permeability, lightweight, flexible fireproof material, characterized by: include: Step S1, preparing a mixed web with different surface densities by needle punching inorganic chopped fiber yarns; Step S2: First, the mixed web is stacked and laid in layers according to the surface density from high to low. During the stacking process, inorganic fiber reinforcements are inserted between the layers of the mixed web and the inorganic fiber reinforcements are evenly distributed between the layers of the mixed web to form a mixed layer; then, the mixed layer is subjected to non-linear phase needle punching to form an intermediate layer; Step S3, subjecting the intermediate layer to low-temperature and low-pressure molding and compounding; the temperature of the low-temperature and low-pressure molding and compounding is 150-220° C., the pressure is 0.04-0.1 MPa, and the time is 6-24 hours; Step S4: an outer layer and an inner layer are respectively arranged on both sides of the molded composite middle layer, and the layers are laid and sewn to obtain a low-permeability, lightweight, flexible fireproof material.

2. The method for preparing a low-permeability, lightweight, flexible fireproof material according to claim 1, characterized in that: The inorganic chopped fiber yarn includes quartz fiber, basalt fiber and mixed fiber, wherein the fiber diameter is 4-9 μm and the fiber length is 50-80 mm; at the same time, the mass of quartz fiber and basalt fiber accounts for 80%-92% of the total mass of the mixed web, and the rest is mixed fiber, wherein the mass of basalt fiber accounts for 20%-65% of the total mass of the mixed web, and the mass of quartz fiber accounts for 25%-72% of the total mass of the mixed web.

3. The method for preparing a low-permeability, lightweight, flexible fireproof material according to claim 2, characterized in that: The hybrid fibers are selected from silicon carbide fibers, alumina fibers, and mullite fibers.

4. The method for preparing a low-permeability, lightweight, flexible fireproof material according to any one of claims 1 to 3, characterized in that: The surface density of the mixed web is in the range of 10 to 80 g / m 2 By adjusting the content of basalt fiber and quartz fiber, the preparation of mixed mesh with different surface densities can be achieved.

5. The method for preparing a low-permeability, lightweight, flexible fireproof material according to any one of claims 1 to 3, characterized in that: The inorganic fiber reinforcement adopts either inorganic fiber continuous yarn or mesh cloth; if the inorganic fiber reinforcement adopts inorganic fiber continuous yarn, a 0° / 90° laying structure is adopted, and the laying distance between adjacent yarns is 5 to 28 mm; if the inorganic fiber reinforcement adopts mesh cloth, its surface density is 40 to 88 g / m 2 .

6. The method for preparing a low-permeability, lightweight, flexible fireproof material according to any one of claims 1 to 3, characterized in that: The needling angle of the non-illegal phase needling is 15° to 40°, and the needling angle is the angle between the needling direction and the normal phase. The needling direction of the non-illegal phase needling is from the high-density side to the low-density side of the mixed layer.

7. The method for preparing a low-permeability, lightweight, flexible fireproof material according to claim 6, characterized in that: The relationship among the surface density of the middle layer, the number of mixed web layers, the number of inorganic fiber reinforcement layers, and the needle punching density is as follows: when the surface density of the middle layer is not greater than 280g / m 2 The number of mixed web layers is 3 to 28, the inorganic fiber reinforcement is made of inorganic fiber continuous yarn, the number of layers is 1 to 5 and is evenly distributed between the mixed webs, and the needle density is 33 to 65 needles / cm 2 ; When the surface density of the middle layer is greater than 280 g / m 2 And not more than 450 g / m 2 The number of layers of the mixed web is 5 to 45, the inorganic fiber reinforcement is either inorganic fiber continuous yarn or mesh cloth, the number of layers of the inorganic fiber continuous yarn is 3 to 8 or the number of layers of the mesh cloth is 1 to 5 and is evenly distributed between the mixed webs, and the needle density is 55 to 95 needles / cm 2 ; When the surface density of the middle layer is greater than 450 g / m 2 and not more than 780 g / m 2 The number of layers of the mixed web is 9 to 60, the inorganic fiber reinforcement is either inorganic fiber continuous yarn or mesh cloth, the number of layers of the inorganic fiber continuous yarn is 7 to 16 or the number of layers of the mesh cloth is 5 to 10 and is evenly distributed between the mixed webs, and the needle density is 85 to 105 needles / cm 2 .

Images