Fire control blanket and preparation process thereof

Abstract

The invention discloses a fire control blanket and a preparation process thereof, and the fire control blanket is characterized in that the fire control blanket comprises a base material layer formed by weaving fibers prepared by drawing, dewaxing, purifying and sintering high silica fibers, the content of silicon dioxide in the high silica fibers is greater than or equal to 96%, a flame-retardant enhancement layer formed by mixing and weaving silicon carbide fibers and basalt fibers according to the proportion of 1: 1, and the flame-retardant enhancement layer is formed by weaving silicon carbide fibers and basalt fibers according to the proportion of 1: 1. The pre-reinforced adhesive layer is embedded into the base material layer to form a three-dimensional reinforced structure, the pre-reinforced adhesive layer is formed by mixing a low-viscosity aluminum phosphate adhesive solution and chopped refractory fibers, the refractory fibers are one or a combination of ceramic fibers (Al2O3SiO2), alumina fibers (Al2O3 is greater than or equal to 95%) and alumina silicate fibers, the diameter of the fibers is 5-15 microns, the length of the fibers is 3-8 mm, and the coating amount of the pre-reinforced adhesive layer is 20-40 g / m < 2 >. The tensile fracture resistance and puncture resistance of the fire control blanket are improved, the high temperature resistance is improved, and the interface bonding force of the fireproof layer is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fire control for electric vehicles, and in particular to a fire control blanket and a preparation process thereof. Background Art

[0002] Traditional fire control materials (such as asbestos blankets and glass fiber blankets) and commercially available improved products (such as basalt fiber blankets) have the following key technical defects in actual applications, which seriously restrict their reliability in high-intensity and high-temperature scenarios: 1. Insufficient tensile and puncture resistance. The root of the problem: Traditional materials rely on the physical strength of a single fiber (such as asbestos or glass fiber) and do not design an interlayer reinforcement structure. For example, asbestos fiber is very brittle, with a tensile breaking strength of ≤500N in the warp direction and ≤400N in the weft direction (GB / T 3923.1 test). It is easy to tear under pulling or impact from sharp objects. Although commercially available basalt fiber blankets have increased their tensile strength to 600N (warp direction) through fiber modification, they still cannot meet the needs of high-intensity operations (such as covering heavy equipment); 2. The contradiction between high-temperature protection performance and structural stability. The root of the problem: In order to improve temperature resistance, traditional fire control blankets often use multi-layer dense structures, which are cumbersome to operate and have poor air permeability. At the same time, ordinary adhesives (such as silicone resins) are easily decomposed at temperatures above 800°C, and the layers separate after burning, posing a significant risk of fire. 3. The interfacial bonding strength between the fiber and the adhesive layer is low. The root cause of the problem: traditional processes use direct coating or simple impregnation. The fiber surface is smooth (roughness ≥ 2μm) and is not chemically activated. The adhesive is only attached by physical adsorption, with an interfacial bonding strength of ≤ 0.5MPa (GB / T 7124 test). At high temperatures, the shrinkage stress of the adhesive layer causes delamination, resulting in loss of blanket integrity. Lightweight and high performance are difficult to coordinate. The root cause of the problem: existing technologies require the superposition of multiple functional layers (base material + adhesive layer + reinforcement layer) to meet fire protection standards (such as GB / T 9978), with a total mass ≥ 1000g / m2, resulting in poor portability. For example, commercially available ceramic fiber blankets (temperature resistant to 1200°C) have a thickness of ≥ 3mm due to their multi-layer structure, making them difficult to quickly fold and store.

[0003] Based on the above analysis, the core contradictions that need to be urgently solved in the existing technology include: how to improve tensile and puncture strength, how to balance high temperature resistance and lightweight, and how to strengthen the fiber-adhesive interface. Therefore, a fire control blanket and its preparation process are proposed. Summary of the Invention

[0004] Based on the technical problems existing in the background technology, the present invention proposes a fire control blanket and a preparation process thereof.

[0005] The present invention provides a fire control blanket comprising: The substrate layer is woven from high-silica fiber prepared by a process of drawing, dewaxing, purification, and sintering, wherein the high-silica fiber contains silicon dioxide (SiO2 content ≥ 96%); The flame-retardant reinforcement layer is made of a 1:1 mix of silicon carbide fiber and basalt fiber, embedded in the base material layer to form a three-dimensional reinforcement structure; The pre-reinforced adhesive layer is composed of a mixture of low-viscosity aluminum phosphate adhesive and short-cut refractory fibers. The refractory fibers are one or a combination of ceramic fibers (Al2O3•SiO2), alumina fibers (Al2O3≥95%), and aluminum silicate fibers. The fiber diameter is 5-15μm and the length is 3-8mm. The coating amount of the pre-reinforced adhesive layer is 20-40g / ㎡. The high-temperature resistant adhesive layer is evenly coated on the surface of the pre-reinforced adhesive layer. It is composed of a phosphate-based inorganic binder and nano-silicon dioxide particles. The particle size of the nano-silicon dioxide particles is 50-100nm, and the coating amount of the high-temperature resistant adhesive layer is 60-90g / ㎡; Sewing structure: The edge of the blanket is sewn with flame-retardant polyimide fiber, and the four corners are equipped with aramid fiber drawstrings with a width of ≥2cm and a grippable length of ≥20cm; the unit area mass of the fire control blanket is ≤800g / ㎡, the tensile breaking strength is ≥880N in the warp direction and ≥680N in the weft direction, and there is no damage or fire after being burned at a high temperature of 1000℃ for 1 hour.

[0006] As a further optimization of the present technical solution, the chopped refractory fibers in the pre-reinforced adhesive layer of the present invention are a mixture of alumina fibers and ceramic fibers in a ratio of 2:1, and the fiber surfaces are pretreated with a silane coupling agent.

[0007] As a further optimization of the technical solution, the thickness of the substrate layer of the present invention is 0.5-1.0 mm, and the surface roughness of the fiber after dewaxing and purification is ≤1 μm.

[0008] The preparation process of the fire control blanket is characterized by comprising the following steps: S1: Preparation of high silica fiber: Wire drawing: SiO2 and Na2O are mixed in a mass ratio of 80:20, the melting temperature is 1600-1650℃, and the fiber diameter is 8-12μm; Dewaxing: immerse the fiber in an acetone solution and ultrasonically clean it for 20-30 minutes to remove surface wax. The acetone solution temperature is 40-50°C and the ultrasonic frequency is 28-40kHz. Purification: immerse the fiber in a 2 mol / L sulfuric acid solution at 60°C for 4 hours to remove sodium ions; Sintering: sintering at 700°C for 2 hours with a shrinkage of ≤15% to obtain high-silica fiber precursor; Weaving: The treated fibers are woven into cloth.

[0009] S2: Composite structure molding: Pre-gluing: low-viscosity aluminum phosphate glue and short-cut refractory fibers are mixed in a mass ratio of 5:1 and applied to the surface of the substrate layer by roller coating to form a pre-reinforced glue layer; Needle Punch Reinforcement: A double needle plate needle punching machine is used to puncture the pre-glued substrate at a density of 100-150 needles / cm², vertically implanting the refractory fibers into the interwoven interface between the substrate layer and the flame retardant reinforcement layer. Thermal activation treatment: Heat at 180-220℃ for 10-15 minutes to soften and flow the pre-reinforced adhesive layer and fill the fiber gaps; Secondary gluing A phosphate-based binder and nano-silica particles were mixed in a mass ratio of 3:1 and sprayed on the activated surface. Nano-SiC / h-BN composite particles were also added (addition amount 10%). Gradient sintering strengthening, Initially cure at 200℃ for 1h, then heat to 450℃ at a rate of 5℃ / min, keep at this temperature for 20min, and cool to 150℃ under nitrogen protection; Sewing, use flame retardant polyimide sewing thread to double-thread lock the edge of the blanket, and assemble aramid drawstrings at the four corners.

[0010] Preferably, the chopped refractory fibers are subjected to plasma treatment before pre-sizing, with a treatment power of 300 W, a mixed gas of N2 and He in a mixing ratio of 3:1, and a treatment time of 5-8 minutes.

[0011] In summary, the beneficial effects of the present invention are: 1. Comprehensive improvement of mechanical properties: The warp / weft tensile breaking strength reaches ≥880N / ≥680N respectively, which is more than 100% higher than traditional materials, meeting the needs of high-intensity fire control scenarios; The puncture strength is ≥450N, which is 50% better than commercial products, attributed to the mechanical anchoring of the chopped fibers and the toughening of the nanoparticles.

[0012] 2. Breakthrough in high temperature resistance: No damage after burning at 1000℃ for 1 hour, mass loss rate ≤5% (traditional materials ≥20%); Nano-SiO2 in the high-temperature resistant adhesive layer forms a dense ceramic protective layer to block heat penetration.

[0013] 3. Interface bonding enhancement: After the pre-reinforced adhesive layer is treated with plasma, the bonding strength between the fiber and the adhesive is increased by 30% (up to 1.2 MPa); the gradient sintering process eliminates internal stress, and the interlayer peeling strength reaches 1.5 MPa (traditional process ≤ 0.8 MPa).

[0014] 4. Balance between lightness and practicality: the total glue quantity is controlled to ≤140g / ㎡, and the mass per unit area is ≤800g / ㎡, which is easy to carry and meets the needs of firefighting operations. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is the microscopic morphology of the fiber in Example 1 after being soaked in a silane coupling agent and then subjected to heat treatment (upper layer at low magnification, lower layer at high magnification). DETAILED DESCRIPTION

[0016] The following will be combined with the contents of the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0017] Example 1: Preparation of fire control blanket 1. Preparation of substrate layer 1.1, Raw materials: SiO2 and Na2O are mixed in a mass ratio of 80:20; 1.2. Equipment: High temperature melting furnace (model HTF-1600, heating rate 10℃ / min); 1.3. Process: Melting temperature is 1625℃, drawing into fiber, fiber diameter is 10μm; 1.4. Dewaxing: Use acetone solution (temperature 45℃), ultrasonic cleaning for 25 minutes, ultrasonic frequency 35kHz, the surface roughness of the fiber after dewaxing and purification is ≤1μm; 1.5. Purification: 2 mol / L sulfuric acid solution at 60°C for 4 hours; 1.6. Sintering: sintering at 700℃ for 2 hours, shrinkage rate 10%.

[0018] 1.7. Weaving: Weaving the treated fibers into cloth.

[0019] 2. Composite structure molding: 2.1 Pre-gluing Composition: Low-viscosity aluminum phosphate glue is compounded with alumina fiber (Al2O3 ≥ 95%) and ceramic fiber (Al2O3•SiO2) in a ratio of 2:1. The fiber diameter is 10μm and the length is 5mm. It is applied to the surface of the substrate layer by roller coating to form a pre-reinforced glue layer. 2.2. Pretreatment: Silane coupling agent KH550 is soaked on the surface of the fiber cloth. The micrograph of the fiber after soaking with silane coupling agent is as follows: Figure 1 shown.

[0020] Coating amount: 30g / ㎡; 2.3. Needle punching enhancement: double needle plate needle punching machine (model DPN-200), needle punching density 130 needles / cm; 2.4. Thermal activation: heating at 200℃ for 12 minutes; 2.5 High temperature resistant adhesive layer Composition: Phosphate-based binder and nano-silica particles (particle size 75nm) are mixed in a ratio of 3:1, and 10% nano-SiC / h-BN composite particles are added; Coating amount: 75g / ㎡; 2.6 Gradient sintering: Initial curing at 200℃ for 1h → heating at 5℃ / min to 450℃ → holding for 20min → quenching to 150℃ with nitrogen; 2.7 Sewing structure The edge is made of flame-retardant polyimide fiber double-line lock-edging, the aramid drawstring width is 2cm and the grippable length is 25cm. The unit area mass of the fire control blanket is ≤800g / ㎡, the tensile breaking strength in the warp direction is ≥880N and in the weft direction is ≥680N, and there is no damage or fire penetration after being burned at a high temperature of 1000℃ for 1 hour.

[0021] Example 2: Compared with Example 1, the difference is: the drawing melting temperature is 1600°C, the drawing fiber diameter is 8μm, the dewaxing acetone temperature is 40°C, the ultrasonic frequency is 28kHz, the pre-glued short refractory fiber diameter is 5μm, the length is 3mm, the needle punching density is 100 needles / cm, the pre-reinforced glue layer coating amount is 20g / ㎡, the thermal activation temperature is 180°C, the heating time is 10 minutes, in the secondary gluing, the particle size of the nano-silica particles is 50nm, and the high-temperature resistant glue layer coating amount is 60g / ㎡.

[0022] Example 3: Compared with Example 1, the difference is that the drawing melting temperature is 1650°C, the drawing fiber diameter is 12μm, the dewaxing acetone temperature is 50°C, the ultrasonic frequency is 40kHz, the pre-gluing short chopped refractory fiber diameter is 15μm, the length is 8mm, the needle punching density is 150 needles / cm, the pre-reinforced glue layer coating amount is 40g / ㎡, the thermal activation temperature is 220°C, the heating time is 15 minutes, in the secondary gluing, the particle size of the nano-silica particles is 100nm, and the high-temperature resistant glue layer coating amount is 90g / ㎡, wherein the short chopped refractory fiber is plasma treated before pre-gluing, the processing power is 300W, N2 and He mixed gas, the mixing ratio is 3:1, and the processing time is 5-8 minutes.

[0023] Comparative Example 1: Compared with Example 1, the pre-reinforced adhesive layer was omitted: only the base material layer and the flame-retardant reinforcement layer were composited.

[0024] Comparative Example 2: Silane coupling agent treatment is canceled: the fibers are directly mixed with the adhesive.

[0025] Comparative experiment Test indicators Mass per unit area, tensile strength at break (warp / weft), and after calcination at 1000°C for 1 hour.

[0026]

[0027] Experimental equipment, tensile testing machine (ASTM D5035 standard), high temperature furnace (model HTO-1000C) For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0028] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0029] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0030] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A fire control blanket, characterized in that: include: The substrate layer is woven from high-silica fibers prepared by a process of drawing, dewaxing, purification, and sintering, wherein the silicon dioxide content of the high-silica fibers is ≥96%; The flame-retardant reinforcement layer is made of a 1:1 mix of silicon carbide fiber and basalt fiber, embedded in the base material layer to form a three-dimensional reinforcement structure; The pre-reinforced adhesive layer is composed of a mixture of low-viscosity aluminum phosphate adhesive and short-cut refractory fibers. The refractory fibers are one or a combination of ceramic fibers (Al2O3·SiO2), alumina fibers (Al2O3 ≥ 95%), and aluminum silicate fibers. The fiber diameter is 5-15μm and the length is 3-8mm. The pre-reinforced adhesive layer is applied at a rate of 20-40g / ㎡. The high-temperature resistant adhesive layer is evenly coated on the surface of the pre-reinforced adhesive layer. It is composed of a phosphate-based inorganic binder and nano-silicon dioxide particles. The particle size of the nano-silicon dioxide particles is 50-100nm, and the coating amount of the high-temperature resistant adhesive layer is 60-90g / ㎡; Sewing structure: The edge of the blanket is sewn with flame-retardant polyimide fiber, and the four corners are equipped with aramid fiber drawstrings. The width of the drawstrings is ≥2cm, and the length of the gripping part is ≥20cm.

2. The fire control blanket according to claim 1, characterized in that: The short chopped refractory fibers in the pre-reinforced adhesive layer are a mixture of alumina fibers and ceramic fibers in a ratio of 2:1, and the fiber surfaces are pre-treated with a silane coupling agent.

3. The fire control blanket according to claim 1, characterized in that: The thickness of the substrate layer is 0.5-1.0 mm, and the surface roughness of the fiber after dewaxing and purification is ≤1 μm.

4. A process for preparing a fire control blanket as claimed in claim 1, characterized in that: The following steps are involved: S1: Preparation of high silica fiber: Wire drawing: SiO2 and Na2O are mixed in a mass ratio of 80:20, the melting temperature is 1600-1650℃, and the fiber diameter is 8-12μm; Dewaxing: immerse the fiber in an acetone solution and ultrasonically clean it for 20-30 minutes to remove surface wax. The acetone solution temperature is 40-50°C and the ultrasonic frequency is 28-40kHz. Purification: immerse the fiber in a 2 mol / L sulfuric acid solution at 60°C for 4 hours to remove sodium ions; Sintering: sintering at 700°C for 2 hours with a shrinkage of ≤15% to obtain high-silica fiber precursor; Weaving: Weaving the treated fibers into cloth; S2: Composite structure molding: Pre-gluing: low-viscosity aluminum phosphate glue and short-cut refractory fibers are mixed in a mass ratio of 5:1 and applied to the surface of the substrate layer by roller coating to form a pre-reinforced glue layer; Needle Punch Reinforcement: A double needle plate needle punching machine is used to puncture the pre-glued substrate at a density of 100-150 needles / cm², vertically implanting the refractory fibers into the interwoven interface between the substrate layer and the flame retardant reinforcement layer. Thermal activation treatment: Heat at 180-220℃ for 10-15 minutes to soften and flow the pre-reinforced adhesive layer and fill the gaps between the fibers; Secondary gluing A phosphate-based binder and nano-silica particles were mixed in a mass ratio of 3:1 and sprayed onto the activated surface. Nano-SiC / h-BN composite particles (10%) were also added. Gradient sintering was used for strengthening, with initial curing at 200°C for 1 hour, followed by heating to 450°C at a rate of 5°C / min, holding for 20 minutes, and rapid cooling to 150°C under nitrogen protection. For sewing, the edges of the blanket were double-locked using flame-retardant polyimide sewing thread, and aramid drawstrings were installed at the four corners.

5. The preparation process according to claim 4, characterized in that: The short chopped refractory fibers are subjected to plasma treatment before pre-sizing, with a treatment power of 300W, a mixed gas of N2 and He at a mixing ratio of 3:1, and a treatment time of 5-8 minutes.

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