Aramid fiber aerogel mobile phone fireproof and explosion-proof bag material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of composite materials, in particular to an aramid fiber aerogel mobile phone fireproof and explosion-proof bag material and a preparation method and application thereof.The fireproof and explosion-proof bag material comprises a fireproof layer, a heat insulation layer and a supporting layer from inside to outside; the fireproof layer is selected from at least one of meta-aramid and para-aramid; the heat insulation layer is silicon dioxide-hydroxyl functional polyimide aerogel; the supporting layer is selected from at least one of meta-aramid and para-aramid; an isocyanate curing agent solution is coated among the layers of the fireproof and explosion-proof bag material, and the fireproof and explosion-proof bag material is obtained by heating and drying after the materials of the layers are compounded. The mass concentration of the isocyanate curing agent in the isocyanate curing agent solution is 15%-30%. According to the flexible aramid fiber aerogel fire-proof and explosion-proof bag material and the preparation method thereof, the bag body strength and the flame-retardant and heat-insulating capacity of a fire-proof and explosion-proof bag can be effectively improved.

Description

Technical Field

[0001] The invention relates to an aramid aerogel mobile phone fireproof and explosion-proof bag material, a preparation method and an application thereof, and belongs to the technical field of composite materials. Background Art

[0002] Mobile phones on the market generally use lithium-ion batteries, which can enable mobile phones to support multiple functions such as games, videos, and online shopping. This requires the lithium-ion batteries used in mobile phones to have extreme performance such as fast charging and discharging, long cycle performance, etc., which greatly increases the risk of smoke, fire and explosion of lithium-ion batteries during charging, discharging or storage. In order to deal with possible safety issues of mobile phones and protect user safety, mobile phone explosion-proof bags are designed to limit the scope of battery explosion or fire through special materials and structural designs.

[0003] Chinese patent CN213487400U proposes a structure that is a fireproof cloth fireproof layer and an aramid fiber cloth explosion-proof layer from the inside to the outside. However, the fireproof layer has low mechanical strength and limited bonding strength with the explosion-proof layer. The surface is easily worn or even torn during the fire and explosion of the lithium-ion battery, and cannot provide sufficient support and protection, and cannot play an excellent explosion-proof function. At the same time, the fireproof layer does not have the function of absorbing heat, so the large amount of heat generated during the thermal failure process poses a risk of heat spread. Chinese patent CN215751248U discloses an aerogel foam gasket for thermal insulation and fire prevention of power batteries, including a packaging film layer I, a fireproof layer I, an aerogel insulation layer, a fireproof layer II and a packaging film layer II; the aerogel insulation layer is located between the fireproof layer I and the fireproof layer II; the outer side of the fireproof layer I is provided with a packaging film layer I, and the outer side of the fireproof layer II is provided with a packaging film layer II, and each layer is compounded together by hot pressing. The layer structure of this patent is relatively complex, and the interlayer peeling strength is low. Chinese patent CN 218985997 U discloses a composite fabric for fire blanket for new energy vehicles, including a surface layer, an intermediate layer, and an inner layer, wherein the surface layer and the inner layer are made of organic flame retardant materials, and the intermediate layer is made of inorganic flame retardant materials, and a layered structure is formed by woven or non-woven methods. Since it adopts an organic-inorganic-organic three-layer composite structure, and the layers are bonded by hot melt adhesive, the organic-inorganic interface has low compatibility, and it is difficult to obtain good bonding and heat insulation effects. Therefore, it is of great value to develop a mobile phone fireproof and explosion-proof bag material with excellent fireproof and explosion-proof performance, simple structure, and high interlayer peeling strength. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides an aramid aerogel mobile phone fireproof and explosion-proof bag material, a preparation method and an application thereof. The aramid aerogel mobile phone fireproof and explosion-proof bag material can effectively reduce the thermal conductivity of the bag body, and improve the fire resistance, thermal insulation performance and the bonding strength between layers.

[0005] The technical solution of the present invention to solve the above technical problems is as follows: an aramid aerogel mobile phone fireproof and explosion-proof bag material, the fireproof and explosion-proof bag material comprises a fireproof layer, a heat insulation layer and a support layer from the inside to the outside; The fireproof layer is selected from at least one of meta-aramid and para-aramid; the heat insulation layer is silica-hydroxyl functionalized polyimide aerogel; the support layer is selected from at least one of meta-aramid and para-aramid; An isocyanate curing agent solution is coated between the layers of the fireproof and explosion-proof bag material. After the layers of material are compounded, they are heated and dried to obtain the fireproof and explosion-proof bag material.

[0006] Furthermore, the preparation method of the silica-hydroxyl functionalized polyimide aerogel comprises the following steps: The aromatic dianhydride, the hydroxyl-functionalized aromatic diamine and the N-methylpyrrolidone solution are mixed to obtain a mixture, and the molar ratio of the aromatic dianhydride to the hydroxyl-functionalized diamine is controlled to be 10:(9-9.5); Adding an N-methylpyrrolidone solution of an aromatic triamine and a silica aerogel powder to the mixture, mixing them evenly, adding a dehydrating agent and a catalyst, mixing them evenly, processing and shaping them, and standing them to gel; the molar ratio of the aromatic triamine to the aromatic dianhydride is (0.35-0.7):10, and the molar ratio of the dehydrating agent to the aromatic dianhydride is (7-8):1; The gel is solvent exchanged in N-methylpyrrolidone and / or acetone solution for 1-5 days, dried by supercritical carbon dioxide, and vacuum dried at 40-80° C. to obtain a silicon dioxide-hydroxyl functionalized polyimide aerogel.

[0007] Further, the aromatic dianhydride is selected from one or more of 3,3',4,4'-biphenyltetracarboxylic dianhydride, pyromellitic dianhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-dibenzophenone tetracarboxylic dianhydride, 3,3',4,4'-triphenyl diether tetracarboxylic dianhydride, and 4,4'-(hexafluoroisopropyl) diphthalic dianhydride; The hydroxyl-functionalized aromatic diamine is 3,3'-dihydroxybenzidine; The aromatic triamine is selected from one or more of 1,3,5-triaminophenoxybenzene and 1,3,5-triaminobenzene; The dehydrating agent is acetic anhydride or propionic anhydride; The catalyst is selected from one or more of pyridine, isoquinoline and β-picoline; The silica aerogel powder has a particle size of 1-20 μm and a density of 0.1-0.12 g / cm 3; In the silica-hydroxyl functionalized polyimide aerogel, the mass proportion of silica aerogel powder is 10-40%, and the mass proportion of polyimide is 60-90%.

[0008] Furthermore, the isocyanate curing agent solution is a solution formed by dissolving an isocyanate curing agent in an organic solvent, the mass concentration of the isocyanate curing agent in the isocyanate curing agent solution is 15%-30%, and the functionality of the isocyanate group in the isocyanate curing agent is not less than 2.

[0009] Furthermore, the organic solvent is any one of benzene, toluene, chlorobenzene, nitrobenzene and acetone.

[0010] Furthermore, the isocyanate curing agent is selected from at least one of diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, toluene diisocyanate, isophorone diisocyanate, and triphenylmethane triisocyanate.

[0011] Furthermore, the thickness of the fireproof layer is 0.5-5 mm, the thickness of the heat insulation layer is 0.02-2 mm, and the thickness of the support layer is 0.5-5 mm.

[0012] Furthermore, based on the total mass of the fireproof and explosion-proof bag material being 100%, the mass of the isocyanate curing agent is 0.1-5%.

[0013] Furthermore, the process conditions of heating and drying are: heating temperature is 40-120° C., and vacuum drying is 12-48 hours.

[0014] Preferably, the fireproof layer is meta-aramid; and the supporting layer is para-aramid.

[0015] The present invention also discloses a method for preparing an aramid aerogel mobile phone fireproof and explosion-proof bag material, the preparation method comprising: coating an isocyanate curing agent solution on the support layer, and placing the heat insulating layer on the support layer coated with the isocyanate curing agent solution; Then, coating the isocyanate curing agent solution on the thermal insulation layer, placing the fireproof layer on the thermal insulation layer, and preparing a composite of the fireproof layer-thermal insulation layer-support layer; The composite of the fireproof layer-heat-insulating layer-support layer is heated and dried to obtain the aramid aerogel mobile phone fireproof and explosion-proof bag material.

[0016] The present invention also discloses an application of an aramid aerogel mobile phone fireproof and explosion-proof bag material. The aramid aerogel mobile phone fireproof and explosion-proof bag material is applied in a mobile phone fireproof and explosion-proof bag. The fireproof layer is used as the inner layer of the mobile phone fireproof and explosion-proof bag, and the support layer is used as the outer layer of the mobile phone fireproof and explosion-proof bag.

[0017] The beneficial effects of the present invention are: The innermost fireproof layer of the fireproof and explosion-proof bag material of the present invention is meta-aramid or para-aramid, which has excellent flame retardancy, high temperature resistance, insulation and chemical stability, can effectively prevent the fire from spreading after the mobile phone catches fire and explodes, and provides a good buffering effect; the heat insulation layer adopts silica-hydroxy modified polyimide aerogel, which has obvious advantages over single inorganic materials or organic polymer aerogels. First, the large specific surface area of ​​silica-hydroxy modified polyimide aerogel can effectively absorb the heat released by thermal failure and reduce the temperature outside the explosion-proof bag. Secondly, polyimide is an organic structure and has good compatibility with the organic fireproof layer and the supporting layer. Thirdly, after polyimide is compounded with silica, it can overcome its high temperature working conditions (such as more than 2 00°C) has the disadvantage of high volume shrinkage, and the heat resistance is further improved. Finally, the rich hydroxyl structure provides more bonding sites for the curing agent, so that a large number of chemical bonds are generated between the fireproof layer and the thermal insulation layer, and between the support layer and the thermal insulation layer, and the interlayer bonding force is significantly improved; the support layer is made of para-aramid or meta-aramid, and the aramid fiber has the advantages of fire retardancy, heat resistance and wear resistance, providing excellent support and fire retardancy for mobile phone fireproof and explosion-proof bags; isocyanate curing agent is coated between the fireproof layer, the thermal insulation layer and the support layer. After vacuum heat treatment, chemical bonds are formed between the isocyanate and the terminal carboxyl / terminal amino group of the aramid, and the terminal amino group and hydroxyl group of the polyimide, so that the bonding force between the fireproof layer, the thermal insulation layer and the support layer is improved, and the mechanical strength of the bag is further improved.

[0018] The fireproof and explosion-proof bag for mobile phones prepared with the fireproof and explosion-proof bag material of the present invention is a portable device with dual functions of fireproof and explosion-proof. On the one hand, the bonding ability between materials such as the fireproof layer, the heat insulation layer, and the support layer is improved through chemical bonding, thereby ensuring the mechanical strength of the bag body, and can effectively suppress the impact caused by the thermal failure of the mobile phone, and control the explosion impact within the explosion-proof bag; on the other hand, the heat generated during the thermal failure process can be absorbed by the heat insulation layer, and the temperature outside the explosion-proof bag can be reduced to achieve a heat insulation effect, thereby reducing the property loss and casualties caused by the fire and explosion of lithium-ion batteries, and improving the safety of mobile phones during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the structure of the fireproof and explosion-proof bag for mobile phones described in the embodiment; Figure 2 Schematic diagram of the layered structure of the fireproof and explosion-proof bag material described in the embodiment; In the figure, 1. fireproof layer; 2. heat insulation layer; 3. support layer; 4. bag body; 5. first-layer aramid flame-retardant Velcro; 6. second-layer aramid flame-retardant Velcro; 7. hand ring. DETAILED DESCRIPTION

[0020] The specific implementation of the present invention is described in detail below. The present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used are only for describing specific embodiments and are not intended to limit the present invention.

[0022] An aramid aerogel mobile phone fireproof and explosion-proof bag material, the fireproof and explosion-proof bag material comprising a fireproof layer, a heat insulation layer and a support layer from the inside to the outside; The fireproof layer is selected from at least one of meta-aramid and para-aramid; the heat insulation layer is silica-hydroxyl functionalized polyimide aerogel; the support layer is selected from at least one of meta-aramid and para-aramid; An isocyanate curing agent solution is coated between the layers of the fireproof and explosion-proof bag material. After the layers of material are compounded, they are heated and dried to obtain the fireproof and explosion-proof bag material.

[0023] Specifically, the preparation method of the silica-hydroxyl functionalized polyimide aerogel comprises the following steps: The aromatic dianhydride, the hydroxyl-functionalized aromatic diamine and the N-methylpyrrolidone solution are mixed to obtain a mixture, and the molar ratio of the aromatic dianhydride to the hydroxyl-functionalized diamine is controlled to be 10:(9-9.5); N-methylpyrrolidone solution of aromatic triamine and silica aerogel powder are added to the mixture, mixed evenly, and a dehydrating agent and a catalyst are added. After mixing evenly, the mixture is processed into a shape and allowed to stand to gel. The molar ratio of the aromatic triamine to the aromatic dianhydride is (0.35-0.7):10, and the molar ratio of the dehydrating agent to the aromatic dianhydride is (7-8):1; the molar amount of the catalyst and the dehydrating agent is equal.

[0024] The gel is solvent exchanged in N-methylpyrrolidone and / or acetone solution for 1-5 days, dried by supercritical carbon dioxide, and vacuum dried at 40-80° C. to obtain a silicon dioxide-hydroxyl functionalized polyimide aerogel.

[0025] Specifically, the aromatic dianhydride is selected from one or more of 3, 3', 4, 4'-biphenyltetracarboxylic dianhydride, pyromellitic dianhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-dibenzophenone tetracarboxylic dianhydride, 3,3',4,4'-triphenyl diether tetracarboxylic dianhydride, and 4,4'-(hexafluoroisopropyl) diphthalic dianhydride; The hydroxyl-functionalized aromatic diamine is 3,3'-dihydroxybenzidine; The aromatic triamine is selected from one or more of 1,3,5-triaminophenoxybenzene and 1,3,5-triaminobenzene; The dehydrating agent is acetic anhydride or propionic anhydride; The catalyst is selected from one or more of pyridine, isoquinoline and β-picoline; The silica aerogel powder has a particle size of 1-20 μm and a density of 0.1-0.12 g / cm 3 ; In the silica-hydroxyl functionalized polyimide aerogel, the mass proportion of silica aerogel powder is 10-40%, and the mass proportion of polyimide is 60-90%.

[0026] Specifically, the isocyanate curing agent solution is a solution formed by dissolving an isocyanate curing agent in an organic solvent, the mass concentration of the isocyanate curing agent in the isocyanate curing agent solution is 15%-30%, and the functionality of the isocyanate group in the isocyanate curing agent is not less than 2.

[0027] Specifically, the organic solvent is any one of benzene, toluene, chlorobenzene, nitrobenzene and acetone.

[0028] Specifically, the isocyanate curing agent is selected from at least one of diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, toluene diisocyanate, isophorone diisocyanate, and triphenylmethane triisocyanate.

[0029] Specifically, the thickness of the fireproof layer is 0.5-5 mm, the thickness of the heat insulation layer is 0.02-2 mm, and the thickness of the support layer is 0.5-5 mm. The fireproof and explosion-proof bag material obtained within this thickness range has moderate hardness and softness, which is more conducive to the processing and preparation of explosion-proof bags.

[0030] More preferably, the thickness of the thermal insulation layer is h , unit is mm; the mass concentration of the isocyanate curing agent in the isocyanate curing agent solution is c , the unit is %; then the relationship between the thickness of the thermal insulation layer and the concentration of the isocyanate curing agent solution is: c = c 0 ±1, c 0 =2.5 h +15; Under this condition, a fireproof and explosion-proof bag material with better mechanical properties and thermal insulation properties can be obtained.

[0031] More preferably, when the mass proportion of polyimide in the thermal insulation layer is relatively large, a relatively thick thermal insulation layer can be used, so that the thermal insulation layer can maintain good viscosity performance and have good thermal insulation effect.

[0032] Specifically, based on the total mass of the fireproof and explosion-proof bag material being 100%, the mass of the isocyanate curing agent is 0.1-5%.

[0033] Specifically, the heating and drying process conditions are: heating temperature is 40-120° C., and vacuum drying is 12-48 hours.

[0034] Preferably, in the fireproof and explosion-proof bag material, the isocyanate curing agent between the heat insulation layer and the support layer (hereinafter referred to as the first curing agent) is 0.05-3% of the total mass of the fireproof and explosion-proof bag material, and the isocyanate curing agent between the fireproof layer and the heat insulation layer (hereinafter referred to as the second curing agent) is 0.05-2% of the total mass of the fireproof and explosion-proof bag material; and the difference between the mass content of the first curing agent and the mass content of the second curing agent is not greater than 1%.

[0035] More preferably, when the mass of the isocyanate curing agent (the total amount of the first curing agent and the second curing agent) accounts for ≥0.1% and <1.5% of the total mass of the fireproof and explosion-proof bag material, the heating temperature is ≥40°C and <60°C; when the mass of the isocyanate curing agent (the total amount of the first curing agent and the second curing agent) accounts for ≥1.5% and ≤5% of the total mass of the fireproof and explosion-proof bag material, the heating temperature is ≥60°C and ≤120°C. When the coating mass of the isocyanate curing agent is small, heating and drying at a relatively low temperature is conducive to the full reaction of the isocyanate curing agent, avoiding the denaturation of the isocyanate curing agent due to excessive heat, thereby affecting the quality of the final product; when the coating mass of the isocyanate curing agent is large, heating and drying at a relatively high temperature is conducive to the rapid reaction of the isocyanate curing agent and improving the production and processing efficiency.

[0036] Preferably, the fireproof layer is meta-aramid and the support layer is para-aramid. Because the fireproof layer is the innermost layer, meta-aramid has higher fireproof and corrosion resistance. If there is a problem with the battery and the electrolyte leaks out, the meta-aramid material can play a good barrier role; the outermost support layer is made of para-aramid material, which has higher wear resistance and is more conducive to the long-term use of the mobile phone fireproof and explosion-proof bag.

[0037] A method for preparing an aramid aerogel mobile phone fireproof and explosion-proof bag material, the preparation method comprising: coating an isocyanate curing agent solution on the support layer, and placing the heat insulating layer on the support layer coated with the isocyanate curing agent solution; Then, coating the isocyanate curing agent solution on the thermal insulation layer, placing the fireproof layer on the thermal insulation layer, and preparing a composite of the fireproof layer-thermal insulation layer-support layer; The composite of the fireproof layer-heat-insulating layer-support layer is heated and dried to obtain the aramid aerogel mobile phone fireproof and explosion-proof bag material.

[0038] The invention discloses an application of an aramid aerogel fireproof and explosion-proof bag material for mobile phones. The aramid aerogel fireproof and explosion-proof bag material for mobile phones is applied in fireproof and explosion-proof bags for mobile phones. The fireproof layer is used as an inner layer of the fireproof and explosion-proof bag for mobile phones, and the support layer is used as an outer layer of the fireproof and explosion-proof bag for mobile phones.

[0039] The sources of raw materials in the following examples and comparative examples of the present invention are as follows. Unless otherwise specified, all other raw materials were obtained from common commercial channels.

[0040] 1. Related raw materials involved in the examples and comparative examples: (1) Meta-aramid: Suzhou Hengsi'an Protection Technology Co., Ltd., meta-aramid fabric.

[0041] (2) Para-aramid: Yantai Taihexing Materials Technology Co., Ltd., para-aramid woven fabric, product number TH5301.

[0042] (3) Diphenylmethane diisocyanate: Shanghai Aladdin Biochemical Technology Co., Ltd., catalog number M106783.

[0043] (4) Polymethylene polyphenyl polyisocyanate: Shanghai Aladdin Biochemical Technology Co., Ltd., product number P304914.

[0044] (5) Toluene diisocyanate: Shanghai Aladdin Biochemical Technology Co., Ltd., product number T135411.

[0045] (6) Triphenylmethane triisocyanate (20% solution, solvent: chlorobenzene): Shanghai Aladdin Biochemical Technology Co., Ltd., catalog number M303165.

[0046] 2. The relevant test standards for materials in the embodiments and comparative examples of the present invention are as follows: (1) Tensile strength: refer to GB / T 34219-2017; (2) Fire resistance: Burn at 1000℃ for 10 minutes and observe whether it burns through; (3) Thermal insulation properties: Burn at 1000°C and test its surface temperature; (4) Thermal conductivity at 200℃, 400℃, 600℃, and 800℃: refer to ASTM C-201; (5) Thermal shrinkage: The residual expansion or contraction of the length after being kept at 200°C for 1 hour and cooled to room temperature; (6) Peel strength test: Refer to GB / T 2791-1995 to test the peel strength between the fireproof layer and the support layer.

[0047] In the present invention, unless otherwise specified, reference may be made to the prior art, such as the coating of the isocyanate curing agent between the layers of materials, and the connection method between the bag body and the hand strap and Velcro. Example 1

[0048] like Figure 1 As shown, the mobile phone fireproof and explosion-proof bag includes: a bag body 4 for accommodating a mobile phone, an opening on the right side of the mobile phone fireproof and explosion-proof bag, and the opening and closing of the mobile phone fireproof and explosion-proof bag are achieved through a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the mobile phone fireproof and explosion-proof bag, and the bag body 4 of the mobile phone fireproof and explosion-proof bag is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0049] like Figure 2 As shown, the fireproof and explosion-proof bag material for making the bag body 4 is a three-layer structure, which is a fireproof layer 1, a heat insulation layer 2 and a support layer 3 from the inside to the outside, and meta-aramid fiber (thickness 0.5mm), silica-hydroxyl functionalized polyimide aerogel (thickness 0.02mm), and para-aramid fiber (thickness 5mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat a diphenylmethane diisocyanate curing agent solution on the support layer 3 (the mass of the curing agent accounts for 0.05% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with the isocyanate curing agent; wherein the diphenylmethane diisocyanate curing agent solution is an acetone solution of diphenylmethane diisocyanate curing agent, and the mass concentration is 15%.

[0050] Step 2: Coat the thermal insulation layer 2 with a diphenylmethane diisocyanate curing agent solution (the mass of the curing agent accounts for 0.05% of the mass of the fireproof and explosion-proof bag material), and place the fireproof layer 1 thereon to prepare a composite of the fireproof layer 1-thermal insulation layer 2-support layer 3. The diphenylmethane diisocyanate curing agent solution is an acetone solution of diphenylmethane diisocyanate curing agent, and the mass concentration is 15%.

[0051] Step 3: vacuum-dry the fireproof layer 1 - heat insulation layer 2 - support layer 3 composite at 40° C. for 48 hours to obtain the fireproof and explosion-proof bag material.

[0052] In this embodiment, the preparation method of silicon dioxide-hydroxyl functionalized polyimide aerogel is: Mixing aromatic dianhydride, hydroxyl-functionalized aromatic diamine and N-methylpyrrolidone solution to obtain a mixture, wherein the molar ratio of aromatic dianhydride to hydroxyl-functionalized diamine is controlled to be 10:9; N-methylpyrrolidone solution of aromatic triamine and silica aerogel powder are added to the mixture, mixed evenly, and a dehydrating agent and a catalyst are added. After mixing evenly, the mixture is processed into a shape and allowed to stand to gel. The molar ratio of the aromatic triamine to the aromatic dianhydride is 0.5:10, and the molar ratio of the dehydrating agent to the aromatic dianhydride is 8:1. The molar amounts of the catalyst and the dehydrating agent are equal.

[0053] The gel was solvent exchanged in N-methylpyrrolidone for 2 days, dried using supercritical carbon dioxide, and vacuum dried at 80° C. to prepare a silica-hydroxyl functionalized polyimide aerogel.

[0054] The aromatic dianhydride is 3,3',4,4'-biphenyltetracarboxylic dianhydride; The hydroxyl-functionalized aromatic diamine is 3,3'-dihydroxybenzidine; The aromatic triamine is 1,3,5-triaminophenoxybenzene; The dehydrating agent is acetic anhydride; The catalyst is pyridine; In the silica-hydroxyl functionalized polyimide aerogel, the mass proportion of silica aerogel powder is 40%, and the mass proportion of polyimide is 60%. Example 2

[0055] like Figure 1 As shown, the mobile phone fireproof and explosion-proof bag includes: a bag body 4 for accommodating a mobile phone, an opening on the right side of the mobile phone fireproof and explosion-proof bag, and the opening and closing of the mobile phone fireproof and explosion-proof bag are achieved through a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the mobile phone fireproof and explosion-proof bag, and the bag body 4 of the mobile phone fireproof and explosion-proof bag is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0056] like Figure 2 As shown, the fireproof and explosion-proof bag material for making the bag body 4 is a three-layer structure, which is a fireproof layer 1, a heat insulation layer 2 and a support layer 3 from the inside to the outside, and meta-aramid fiber (thickness 5mm), silica-hydroxyl functionalized polyimide aerogel (thickness 1mm), and para-aramid fiber (thickness 0.5mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat the support layer 3 with a toluene diisocyanate curing agent solution (the mass of the curing agent accounts for 1% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with the isocyanate curing agent; wherein the toluene diisocyanate curing agent solution is a benzene solution of toluene diisocyanate curing agent, and the mass concentration is 18%.

[0057] Step 2: Coat the thermal insulation layer 2 with a toluene diisocyanate curing agent solution (the mass of the curing agent accounts for 0.5% of the mass of the fireproof and explosion-proof bag material), and place the fireproof layer 1 thereon to prepare a composite of the fireproof layer 1-thermal insulation layer 2-support layer 3. The toluene diisocyanate curing agent solution is a benzene solution of toluene diisocyanate curing agent, and the mass concentration is 18%.

[0058] Step 3: vacuum-dry the fireproof layer 1 - heat insulation layer 2 - support layer 3 composite at 60° C. for 24 hours to obtain the fireproof and explosion-proof bag material.

[0059] In this embodiment, the preparation method of silicon dioxide-hydroxyl functionalized polyimide aerogel is: The aromatic dianhydride, the hydroxyl-functionalized aromatic diamine and the N-methylpyrrolidone solution are mixed to obtain a mixture, wherein the molar ratio of the aromatic dianhydride to the hydroxyl-functionalized diamine is controlled to be 10:9.5; N-methylpyrrolidone solution of aromatic triamine and silica aerogel powder are added to the mixture, mixed evenly, a dehydrating agent and a catalyst are added, mixed evenly, processed into a shape and allowed to stand to gel; the molar ratio of the aromatic triamine to the aromatic dianhydride is 0.35:10, and the molar ratio of the dehydrating agent to the aromatic dianhydride is 7:1; the molar amounts of the catalyst and the dehydrating agent are equal.

[0060] The gel was solvent exchanged in an acetone solution for 5 days, dried using supercritical carbon dioxide, and vacuum dried at 40° C. to prepare a silica-hydroxyl functionalized polyimide aerogel.

[0061] The aromatic dianhydride is pyromellitic dianhydride; The hydroxyl-functionalized aromatic diamine is 3,3'-dihydroxybenzidine; The aromatic triamine is 1,3,5-triaminobenzene; The dehydrating agent is propionic anhydride; The catalyst is isoquinoline; In the silica-hydroxyl functionalized polyimide aerogel, the mass proportion of silica aerogel powder is 25%, and the mass proportion of polyimide is 75%. Example 3

[0062] like Figure 1 As shown, the mobile phone fireproof and explosion-proof bag includes: a bag body 4 for accommodating a mobile phone, an opening on the right side of the mobile phone fireproof and explosion-proof bag, and the opening and closing of the mobile phone fireproof and explosion-proof bag are achieved through a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the mobile phone fireproof and explosion-proof bag, and the bag body 4 of the mobile phone fireproof and explosion-proof bag is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0063] like Figure 2 As shown, the fireproof and explosion-proof bag material for making the bag body 4 is a three-layer structure, which is a fireproof layer 1, a heat insulation layer 2 and a support layer 3 from the inside to the outside, and meta-aramid fiber (thickness 2mm), silica-hydroxyl functionalized polyimide aerogel (thickness 2mm), and para-aramid fiber (thickness 2mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat a polymethylene polyphenyl polyisocyanate curing agent solution on the support layer 3 (the mass of the curing agent accounts for 0.5% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with the isocyanate curing agent; wherein the polymethylene polyphenyl polyisocyanate curing agent solution is a toluene solution of the polymethylene polyphenyl polyisocyanate curing agent, and the mass concentration is 20%.

[0064] Step 2: Coat the thermal insulation layer 2 with a polymethylene polyphenyl polyisocyanate curing agent (the mass of the curing agent accounts for 1% of the mass of the fireproof and explosion-proof bag material), and place the fireproof layer 1 thereon to prepare a composite of the fireproof layer 1-thermal insulation layer 2-support layer 3. The polymethylene polyphenyl polyisocyanate curing agent solution is a toluene solution of the polymethylene polyphenyl polyisocyanate curing agent, and the mass concentration is 20%.

[0065] Step 3: vacuum drying the fireproof layer 1-heat insulation layer 2-support layer 3 composite at 100° C. for 20 hours to obtain the fireproof and explosion-proof bag material.

[0066] In this embodiment, the preparation method of silicon dioxide-hydroxyl functionalized polyimide aerogel is: Mixing aromatic dianhydride, hydroxyl-functionalized aromatic diamine and N-methylpyrrolidone solution to obtain a mixture, wherein the molar ratio of aromatic dianhydride to hydroxyl-functionalized diamine is controlled to be 10:9; Adding an N-methylpyrrolidone solution of an aromatic triamine and a silica aerogel powder to the mixture, mixing them evenly, adding a dehydrating agent and a catalyst, mixing them evenly, processing and shaping them, and standing them to gel; the molar ratio of the aromatic triamine to the aromatic dianhydride is 0.7:10, and the molar ratio of the dehydrating agent to the aromatic dianhydride is 8:1; The gel was solvent exchanged in an N-methylpyrrolidone solution for 1 day, dried using supercritical carbon dioxide, and vacuum dried at 80° C. to obtain a silica-hydroxyl functionalized polyimide aerogel.

[0067] Further, the aromatic dianhydride is 3,3',4,4'-benzophenone tetracarboxylic dianhydride; The hydroxyl-functionalized aromatic diamine is 3,3'-dihydroxybenzidine; The aromatic triamine is 1,3,5-triaminophenoxybenzene; The dehydrating agent is propionic anhydride; The catalyst is β-picoline; In the silica-hydroxyl functionalized polyimide aerogel, the mass proportion of silica aerogel powder is 10%, and the mass proportion of polyimide is 90%. Example 4

[0068] like Figure 1 As shown, the mobile phone fireproof and explosion-proof bag includes: a bag body 4 for accommodating a mobile phone, an opening on the right side of the mobile phone fireproof and explosion-proof bag, and the opening and closing of the mobile phone fireproof and explosion-proof bag are achieved through a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the mobile phone fireproof and explosion-proof bag, and the bag body 4 of the mobile phone fireproof and explosion-proof bag is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0069] like Figure 2 As shown, the fireproof and explosion-proof bag material for making the bag body 4 is a three-layer structure, which is a fireproof layer 1, a heat insulation layer 2 and a support layer 3 from the inside to the outside, and meta-aramid fiber (thickness 2mm), silica-hydroxyl functionalized polyimide aerogel (thickness 2mm), and para-aramid fiber (thickness 2mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat a triphenylmethane triisocyanate curing agent solution on the support layer 3 (the mass of the curing agent accounts for 3% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with the isocyanate curing agent; wherein the triphenylmethane triisocyanate curing agent solution is a chlorobenzene solution of triphenylmethane triisocyanate curing agent, and the mass concentration is 20%.

[0070] Step 2: Coat triphenylmethane triisocyanate curing agent on the thermal insulation layer 2 (the mass of the curing agent accounts for 2% of the mass of the fireproof and explosion-proof bag material), place the fireproof layer 1 thereon, and prepare a composite of fireproof layer 1-thermal insulation layer 2-support layer 3. The triphenylmethane triisocyanate curing agent solution is a chlorobenzene solution of triphenylmethane triisocyanate curing agent, and the mass concentration is 20%.

[0071] Step 3: vacuum-dry the fireproof layer 1 - heat insulation layer 2 - support layer 3 composite at 120° C. for 12 hours to obtain the fireproof and explosion-proof bag material.

[0072] In this embodiment, the preparation method of silicon dioxide-hydroxyl functionalized polyimide aerogel is: Mixing aromatic dianhydride, hydroxyl-functionalized aromatic diamine and N-methylpyrrolidone solution to obtain a mixture, wherein the molar ratio of aromatic dianhydride to hydroxyl-functionalized diamine is controlled to be 10:9.5; Adding an N-methylpyrrolidone solution of an aromatic triamine and a silica aerogel powder to the mixture, mixing them evenly, adding a dehydrating agent and a catalyst, mixing them evenly, processing and shaping them, and standing them to gel; the molar ratio of the aromatic triamine to the aromatic dianhydride is 0.6:10, and the molar ratio of the dehydrating agent to the aromatic dianhydride is 8:1; The gel was solvent exchanged in an N-methylpyrrolidone solution for 1 day, dried using supercritical carbon dioxide, and vacuum dried at 80° C. to obtain a silica-hydroxyl functionalized polyimide aerogel.

[0073] Further, the aromatic dianhydride is 3,3',4,4'-benzophenone tetracarboxylic dianhydride; The hydroxyl-functionalized aromatic diamine is 3,3'-dihydroxybenzidine; The aromatic triamine is 1,3,5-triaminophenoxybenzene; The dehydrating agent is propionic anhydride; The catalyst is β-picoline; In the silica-hydroxyl functionalized polyimide aerogel, the mass proportion of silica aerogel powder is 10%, and the mass proportion of polyimide is 90%. Example 5

[0074] like Figure 1 As shown, the mobile phone fireproof and explosion-proof bag includes: a bag body 4 for accommodating a mobile phone, an opening on the right side of the mobile phone fireproof and explosion-proof bag, and the opening and closing of the mobile phone fireproof and explosion-proof bag are achieved through a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the mobile phone fireproof and explosion-proof bag, and the bag body 4 of the mobile phone fireproof and explosion-proof bag is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0075] like Figure 2 As shown, the fireproof and explosion-proof bag material for making the bag body 4 is a three-layer structure, which is a fireproof layer 1, a heat insulation layer 2 and a support layer 3 from the inside to the outside, and meta-aramid fiber (thickness 2mm), silica-hydroxyl functionalized polyimide aerogel (thickness 2mm), and para-aramid fiber (thickness 2mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat a polymethylene polyphenyl polyisocyanate curing agent solution on the support layer 3 (the mass of the curing agent accounts for 0.5% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with the isocyanate curing agent; wherein the polymethylene polyphenyl polyisocyanate curing agent solution is a toluene solution of the polymethylene polyphenyl polyisocyanate curing agent, and the mass concentration is 30%.

[0076] Step 2: Coat the thermal insulation layer 2 with a polymethylene polyphenyl polyisocyanate curing agent (the mass of the curing agent accounts for 1% of the mass of the fireproof and explosion-proof bag material), and place the fireproof layer 1 thereon to prepare a composite of the fireproof layer 1-thermal insulation layer 2-support layer 3. The polymethylene polyphenyl polyisocyanate curing agent solution is a toluene solution of the polymethylene polyphenyl polyisocyanate curing agent, and the mass concentration is 30%.

[0077] Step 3: vacuum drying the fireproof layer 1-heat insulation layer 2-support layer 3 composite at 100° C. for 20 hours to obtain the fireproof and explosion-proof bag material.

[0078] In this embodiment, the preparation method of the silica-hydroxyl functionalized polyimide aerogel is the same as that of Embodiment 3. Example 6

[0079] like Figure 1 As shown, the mobile phone fireproof and explosion-proof bag includes: a bag body 4 for accommodating a mobile phone, an opening on the right side of the mobile phone fireproof and explosion-proof bag, and the opening and closing of the mobile phone fireproof and explosion-proof bag are achieved through a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the mobile phone fireproof and explosion-proof bag, and the bag body 4 of the mobile phone fireproof and explosion-proof bag is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0080] like Figure 2 As shown, the fireproof and explosion-proof bag material for making the bag body 4 is a three-layer structure, which is a fireproof layer 1, a heat insulation layer 2 and a support layer 3 from the inside to the outside, and meta-aramid fiber (thickness 0.5mm), silica-hydroxyl functionalized polyimide aerogel (thickness 0.02mm), and para-aramid fiber (thickness 5mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat a diphenylmethane diisocyanate curing agent solution on the support layer 3 (the mass of the curing agent accounts for 0.05% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with the isocyanate curing agent; wherein the diphenylmethane diisocyanate curing agent solution is an acetone solution of diphenylmethane diisocyanate curing agent, and the mass concentration is 15%.

[0081] Step 2: Coat the thermal insulation layer 2 with a diphenylmethane diisocyanate curing agent solution (the mass of the curing agent accounts for 0.05% of the mass of the fireproof and explosion-proof bag material), and place the fireproof layer 1 thereon to prepare a composite of the fireproof layer 1-thermal insulation layer 2-support layer 3. The diphenylmethane diisocyanate curing agent solution is an acetone solution of diphenylmethane diisocyanate curing agent, and the mass concentration is 15%.

[0082] Step 3: vacuum-dry the fireproof layer 1 - heat insulation layer 2 - support layer 3 composite at 80° C. for 24 hours to obtain the fireproof and explosion-proof bag material.

[0083] In this embodiment, the preparation method of the silica-hydroxyl functionalized polyimide aerogel is the same as that in Embodiment 1.

[0084] Comparative Example 1

[0085] The fireproof and explosion-proof bag material is prepared by the same method as in Example 1, except that: there is no heat insulation layer 2 in this comparative example 1. The specific preparation process is as follows: The fireproof and explosion-proof bag for mobile phones comprises: a bag body 4 for accommodating mobile phones, an opening on the right side of the fireproof and explosion-proof bag for mobile phones, and the opening and closing of the fireproof and explosion-proof bag for mobile phones are realized by means of a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the fireproof and explosion-proof bag for mobile phones, and the bag body 4 of the fireproof and explosion-proof bag for mobile phones is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0086] The fireproof and explosion-proof bag material used to make the bag body 4 is a two-layer structure, which is a fireproof layer 1 and a support layer 3 from the inside to the outside. Meta-aramid fiber (thickness 0.5 mm) and para-aramid fiber (thickness 5 mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat a layer of diphenylmethane diisocyanate curing agent solution on the support layer 3 (the mass of the curing agent accounts for 0.1% of the mass of the fireproof and explosion-proof bag material), place the fireproof layer 1 thereon, and prepare a fireproof layer 1-support layer 3 composite; wherein the diphenylmethane diisocyanate curing agent solution is an acetone solution of diphenylmethane diisocyanate curing agent, and the mass concentration is 15%.

[0087] Step 2: vacuum-dry the fireproof layer 1-support layer 3 composite at 40° C. for 48 hours to obtain the flexible aramid aerogel fireproof and explosion-proof bag.

[0088] Comparative Example 2

[0089] The fireproof and explosion-proof bag material is prepared by the same method as in Example 1, except that the materials of the fireproof layer 1 and the support layer 3 are changed in this comparative example 2. The specific preparation process is as follows: The fireproof and explosion-proof bag for mobile phones comprises: a bag body 4 for accommodating mobile phones, an opening on the right side of the fireproof and explosion-proof bag for mobile phones, and the opening and closing of the fireproof and explosion-proof bag for mobile phones are realized by means of a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the fireproof and explosion-proof bag for mobile phones, and the bag body 4 of the fireproof and explosion-proof bag for mobile phones is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0090] The fireproof and explosion-proof bag material used to make the bag body 4 is a three-layer structure, which includes a fireproof layer 1, a heat insulation layer 2, and a support layer 3 from the inside to the outside. Acrylic fiber (thickness 0.5 mm), silica-hydroxyl functionalized polyimide aerogel (thickness 0.02 mm), and acrylic fiber (thickness 5 mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat a diphenylmethane diisocyanate curing agent solution on the support layer 3 (the mass of the curing agent accounts for 0.05% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with the isocyanate curing agent; wherein the diphenylmethane diisocyanate curing agent solution is an acetone solution of diphenylmethane diisocyanate curing agent, and the mass concentration is 15%.

[0091] Step 2: Coat the thermal insulation layer 2 with a diphenylmethane diisocyanate curing agent solution (the mass of the curing agent accounts for 0.05% of the mass of the fireproof and explosion-proof bag material), and place the fireproof layer 1 thereon to prepare a composite of the fireproof layer 1-thermal insulation layer 2-support layer 3. The diphenylmethane diisocyanate curing agent solution is an acetone solution of diphenylmethane diisocyanate curing agent, and the mass concentration is 15%.

[0092] Step 3: vacuum-dry the fireproof layer 1 - heat insulation layer 2 - support layer 3 composite at 40° C. for 48 hours to obtain the fireproof and explosion-proof bag material.

[0093] Comparative Example 3

[0094] The fireproof and explosion-proof bag material is prepared by the same method as in Example 1, except that the isocyanate curing agent is replaced with a PVDF binder in this comparative example 3. The specific preparation process is as follows: The fireproof and explosion-proof bag for mobile phones comprises: a bag body 4 for accommodating mobile phones, an opening on the right side of the fireproof and explosion-proof bag for mobile phones, and the opening and closing of the fireproof and explosion-proof bag for mobile phones are realized by means of a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the fireproof and explosion-proof bag for mobile phones, and the bag body 4 of the fireproof and explosion-proof bag for mobile phones is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0095] The fireproof and explosion-proof bag material used to make the bag body 4 is a three-layer structure, which includes a fireproof layer 1, a heat insulation layer 2 and a support layer 3 from the inside to the outside. Meta-aramid fiber (thickness 0.5 mm), silica-hydroxyl functionalized polyimide aerogel (thickness 0.02 mm), and para-aramid fiber (thickness 5 mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat the support layer 3 with a PVDF binder solution (the mass of the PVDF binder accounts for 0.05% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with an isocyanate curing agent; wherein the PVDF binder solution is an NMP solution of a PVDF binder with a mass concentration of 20%.

[0096] Step 2: Coat the thermal insulation layer 2 with a PVDF binder solution (the mass of the PVDF binder accounts for 0.05% of the mass of the fireproof and explosion-proof bag material), and place the fireproof layer 1 thereon to prepare a composite of the fireproof layer 1-thermal insulation layer 2-support layer 3. The PVDF binder solution is a NMP solution of PVDF binder, and the mass concentration is 20%.

[0097] Step 3: vacuum-dry the fireproof layer 1 - heat insulation layer 2 - support layer 3 composite at 40° C. for 48 hours to obtain the fireproof and explosion-proof bag material.

[0098] Comparative Example 4

[0099] The fireproof and explosion-proof bag material is prepared by the same method as in Example 3, except that the mass concentration of the isocyanate curing agent solution is reduced in this comparative example 4, and the mass concentration of the isocyanate curing agent solution in this comparative example 4 is 10% (lower than the mass concentration specified in the present invention). The specific preparation process is as follows: The fireproof and explosion-proof bag for mobile phones comprises: a bag body 4 for accommodating mobile phones, an opening on the right side of the fireproof and explosion-proof bag for mobile phones, and the opening and closing of the fireproof and explosion-proof bag for mobile phones are realized by means of a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the fireproof and explosion-proof bag for mobile phones, and the bag body 4 of the fireproof and explosion-proof bag for mobile phones is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0100] The fireproof and explosion-proof bag material used to make the bag body 4 is a three-layer structure, which includes a fireproof layer 1, a heat insulation layer 2, and a support layer 3 from the inside to the outside. Meta-aramid fiber (thickness 2 mm), silica-hydroxyl functionalized polyimide aerogel (thickness 2 mm), and para-aramid fiber (thickness 2 mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat a polymethylene polyphenyl polyisocyanate curing agent solution on the support layer 3 (the mass of the curing agent accounts for 0.5% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with the isocyanate curing agent; wherein the polymethylene polyphenyl polyisocyanate curing agent solution is a toluene solution of the polymethylene polyphenyl polyisocyanate curing agent, and the mass concentration is 10%.

[0101] Step 2: Coat the thermal insulation layer 2 with a polymethylene polyphenyl polyisocyanate curing agent (the mass of the curing agent accounts for 1% of the mass of the fireproof and explosion-proof bag material), and place the fireproof layer 1 thereon to prepare a composite of the fireproof layer 1-thermal insulation layer 2-support layer 3. The polymethylene polyphenyl polyisocyanate curing agent solution is a toluene solution of the polymethylene polyphenyl polyisocyanate curing agent, and the mass concentration is 10%.

[0102] Step 3: vacuum drying the fireproof layer 1-heat insulation layer 2-support layer 3 composite at 100° C. for 20 hours to obtain the fireproof and explosion-proof bag material.

[0103] Comparative Example 5

[0104] The fireproof and explosion-proof bag material is prepared by the same method as in Example 3, except that: the mass concentration of the isocyanate curing agent solution is increased in this comparative example 5, and the mass concentration of the isocyanate curing agent solution in this comparative example 5 is 35% (higher than the mass concentration specified in the present invention). The specific preparation process is as follows: The fireproof and explosion-proof bag for mobile phones comprises: a bag body 4 for accommodating mobile phones, an opening on the right side of the fireproof and explosion-proof bag for mobile phones, and the opening and closing of the fireproof and explosion-proof bag for mobile phones are realized by means of a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the fireproof and explosion-proof bag for mobile phones, and the bag body 4 of the fireproof and explosion-proof bag for mobile phones is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0105] The fireproof and explosion-proof bag material used to make the bag body 4 is a three-layer structure, which includes a fireproof layer 1, a heat insulation layer 2, and a support layer 3 from the inside to the outside. Meta-aramid fiber (thickness 2 mm), silica-hydroxyl functionalized polyimide aerogel (thickness 2 mm), and para-aramid fiber (thickness 2 mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat a polymethylene polyphenyl polyisocyanate curing agent solution on the support layer 3 (the mass of the curing agent accounts for 0.5% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with the isocyanate curing agent; wherein the polymethylene polyphenyl polyisocyanate curing agent solution is a toluene solution of the polymethylene polyphenyl polyisocyanate curing agent, and the mass concentration is 35%.

[0106] Step 2: Coat the thermal insulation layer 2 with a polymethylene polyphenyl polyisocyanate curing agent (the mass of the curing agent accounts for 1% of the mass of the fireproof and explosion-proof bag material), and place the fireproof layer 1 thereon to prepare a composite of the fireproof layer 1-thermal insulation layer 2-support layer 3. The polymethylene polyphenyl polyisocyanate curing agent solution is a toluene solution of the polymethylene polyphenyl polyisocyanate curing agent, and the mass concentration is 35%.

[0107] Step 3: vacuum drying the fireproof layer 1-heat insulation layer 2-support layer 3 composite at 100° C. for 20 hours to obtain the fireproof and explosion-proof bag material.

[0108] The tensile strength, fire resistance, thermal insulation, thermal conductivity and peel strength of the mobile phone explosion-proof bags of the embodiment and the comparative example were tested respectively. The specific results are shown in Table 1.

[0109] Comparative Example 6

[0110] The fireproof and explosion-proof bag material is prepared by the same method as in Example 1, except that the material of the heat insulation layer 2 is changed in this comparative example 6. The specific preparation process is as follows: The fireproof and explosion-proof bag for mobile phones comprises: a bag body 4 for accommodating mobile phones, an opening on the right side of the fireproof and explosion-proof bag for mobile phones, and the opening and closing of the fireproof and explosion-proof bag for mobile phones are realized by means of a first meta-aramid flame-retardant Velcro 5 and a second meta-aramid flame-retardant Velcro 6, a hand ring 7 made of meta-aramid fiber is added to the upper right corner of the fireproof and explosion-proof bag for mobile phones, and the bag body 4 of the fireproof and explosion-proof bag for mobile phones is fixed between the meta-aramid flame-retardant yarn and the hand ring 7.

[0111] The fireproof and explosion-proof bag material used to make the bag body 4 is a three-layer structure, which includes a fireproof layer 1, a heat insulation layer 2 and a support layer 3 from the inside to the outside. Meta-aramid fiber (thickness 0.5 mm), polyimide aerogel (thickness 0.02 mm), and para-aramid fiber (thickness 5 mm) are selected respectively. The fireproof and explosion-proof bag material is prepared by the following method: Step 1: Coat a diphenylmethane diisocyanate curing agent solution on the support layer 3 (the mass of the curing agent accounts for 0.05% of the mass of the fireproof and explosion-proof bag material), and place the thermal insulation layer 2 on the support layer 3 coated with the isocyanate curing agent; wherein the diphenylmethane diisocyanate curing agent solution is an acetone solution of diphenylmethane diisocyanate curing agent, and the mass concentration is 15%.

[0112] Step 2: Coat the thermal insulation layer 2 with a diphenylmethane diisocyanate curing agent solution (the mass of the curing agent accounts for 0.05% of the mass of the fireproof and explosion-proof bag material), and place the fireproof layer 1 thereon to prepare a composite of the fireproof layer 1-thermal insulation layer 2-support layer 3. The diphenylmethane diisocyanate curing agent solution is an acetone solution of diphenylmethane diisocyanate curing agent, and the mass concentration is 15%.

[0113] Step 3: vacuum-dry the fireproof layer 1 - heat insulation layer 2 - support layer 3 composite at 40° C. for 48 hours to obtain the fireproof and explosion-proof bag material.

[0114] Comparative Example 7

[0115] The fireproof and explosion-proof bag material was prepared by the same method as in Example 1, except that: when preparing the silica-hydroxyl functionalized polyimide aerogel in this comparative example 7, no aromatic triamine was added. The specific preparation process is as follows: Mixing aromatic dianhydride, hydroxyl-functionalized aromatic diamine and N-methylpyrrolidone solution to obtain a mixture, wherein the molar ratio of aromatic dianhydride to hydroxyl-functionalized diamine is controlled to be 10:9; Add silica aerogel powder to the mixture, mix evenly, add dehydrating agent and catalyst, mix evenly, process into shape and let stand to gel; the molar ratio of the dehydrating agent to the aromatic dianhydride is 8:1; the molar amount of the catalyst and the dehydrating agent is equal.

[0116] The gel was solvent exchanged in N-methylpyrrolidone for 2 days, dried using supercritical carbon dioxide, and vacuum dried at 80° C. to prepare a silica-hydroxyl functionalized polyimide aerogel.

[0117] The aromatic dianhydride is 3,3',4,4'-biphenyltetracarboxylic dianhydride; The hydroxyl-functionalized aromatic diamine is 3,3'-dihydroxybenzidine; The dehydrating agent is acetic anhydride; The catalyst is pyridine; In the silica-hydroxyl functionalized polyimide aerogel, the mass proportion of silica aerogel powder is 40%, and the mass proportion of polyimide is 60%.

[0118] Comparative Example 8

[0119] The fireproof and explosion-proof bag material was prepared by the same method as in Example 1, except that: when preparing the thermal insulation layer material in this comparative example 8, no silica aerogel powder was added, which was equivalent to preparing: hydroxyl functionalized polyimide aerogel, and the specific preparation process was as follows: Mixing aromatic dianhydride, hydroxyl-functionalized aromatic diamine and N-methylpyrrolidone solution to obtain a mixture, wherein the molar ratio of aromatic dianhydride to hydroxyl-functionalized diamine is controlled to be 10:9; Adding an N-methylpyrrolidone solution of an aromatic triamine to the mixture, mixing evenly, adding a dehydrating agent and a catalyst, mixing evenly, processing and shaping, and standing to gel; the molar ratio of the aromatic triamine to the aromatic dianhydride is 0.5:10, and the molar ratio of the dehydrating agent to the aromatic dianhydride is 8:1; the molar amounts of the catalyst and the dehydrating agent are equal.

[0120] The gel was solvent exchanged in N-methylpyrrolidone for 2 days, dried using supercritical carbon dioxide, and vacuum dried at 80° C. to obtain a hydroxyl-functionalized polyimide aerogel.

[0121] The aromatic dianhydride is 3,3',4,4'-biphenyltetracarboxylic dianhydride; The hydroxyl-functionalized aromatic diamine is 3,3'-dihydroxybenzidine; The aromatic triamine is 1,3,5-triaminophenoxybenzene; The dehydrating agent is acetic anhydride; The catalyst is pyridine.

[0122] Comparative Example 9

[0123] The fireproof and explosion-proof bag material is prepared by the same method as in Example 1, except that: when preparing the thermal insulation layer material in this comparative example 9, 3,3'-dihydroxybenzidine is replaced with 3,3'-dimethoxybenzidine, which is equivalent to preparing: silica-polyimide aerogel, and the specific preparation process is as follows: Mixing aromatic dianhydride, diamine and N-methylpyrrolidone solution to obtain a mixture, wherein the molar ratio of aromatic dianhydride to hydroxyl functionalized diamine is controlled to be 10:9; N-methylpyrrolidone solution of aromatic triamine and silica aerogel powder are added to the mixture, mixed evenly, and a dehydrating agent and a catalyst are added. After mixing evenly, the mixture is processed into a shape and allowed to stand to gel. The molar ratio of the aromatic triamine to the aromatic dianhydride is 0.5:10, and the molar ratio of the dehydrating agent to the aromatic dianhydride is 8:1. The molar amounts of the catalyst and the dehydrating agent are equal.

[0124] The gel was solvent exchanged in N-methylpyrrolidone for 2 days, dried using supercritical carbon dioxide, and vacuum dried at 80° C. to prepare a silica-polyimide aerogel.

[0125] The aromatic dianhydride is 3,3',4,4'-biphenyltetracarboxylic dianhydride; The diamine is 3,3'-dihydroxybenzidine; The aromatic triamine is 1,3,5-triaminophenoxybenzene; The dehydrating agent is acetic anhydride; The catalyst is pyridine; In the silica-polyimide aerogel, the mass proportion of silica aerogel powder is 40%, and the mass proportion of polyimide is 60%.

[0126] Table 1 Test data of embodiments and comparative examples

[0127] From the above table data, it can be seen that the fireproof and explosion-proof bag materials prepared by the preparation method of the present invention in Examples 1 to 6 can effectively reduce the thermal conductivity of the bag body and improve the fire resistance, thermal insulation performance and the bonding strength between each layer when used in fireproof and explosion-proof bags. In addition, from the comparison of the data of Example 3 and Example 5, it can be seen that when the relationship between the thickness of the thermal insulation layer and the concentration of the isocyanate curing agent solution is c = c 0 ±1 and c 0 =2.5 h +15, the fire-resistant, heat-insulating and strength properties of the obtained bag are even better; from the comparison of the data in Example 1 and Example 6, it can be seen that: when the mass proportion of the isocyanate curing agent in the total mass of the fire-proof and explosion-proof bag material is ≥0.1% and <1.5%, the heating temperature is ≥40°C and <60°C, which is more conducive to obtaining a product with excellent fire-resistant, heat-insulating and mechanical properties.

[0128] From the data comparison between Comparative Example 1 and Example 1, it can be seen that if the aerogel insulation layer 2 is not added to the fireproof and explosion-proof bag, the thermal insulation performance of the fireproof and explosion-proof bag will be significantly reduced. Therefore, the layer structure of the fireproof and explosion-proof bag material of the present invention is more conducive to obtaining a fireproof and explosion-proof bag with excellent fire resistance and thermal insulation performance.

[0129] From the data comparison between Comparative Example 2 and Example 1, it can be seen that if the materials of the fireproof layer 1 and the support layer 3 are replaced with acrylic fiber, the interlayer peel strength and the fire-resistant and heat-insulating properties of the fireproof and explosion-proof bag are significantly reduced. Therefore, the mutual cooperation of the fireproof layer 1, the heat-insulating layer 2, the support layer 3 and the diisocyanate curing agent in the preparation method of the present invention is more conducive to obtaining a fireproof and explosion-proof bag with excellent performance.

[0130] From the data comparison between Comparative Example 3 and Example 1, it can be seen that if the diisocyanate curing agent is replaced with PVDF adhesive, the interlayer peel strength, fire resistance and heat insulation, and strength properties of the fireproof and explosion-proof bag will be significantly reduced. The fireproof layer, heat insulation layer, and support layer of the bag body of the present invention are coated with an isocyanate curing agent. After vacuum heat treatment, chemical bonds are formed between the isocyanate and the terminal carboxyl / terminal amino groups of the aramid, and the terminal amino groups and hydroxyl groups of the polyimide, so that the bonding force between the fireproof layer, the heat insulation layer, and the support layer is improved, and the mechanical strength of the bag is further improved. Moreover, the silica-hydroxyl functionalized polyimide aerogel can maximize the thermal insulation performance, and the para-aramid and meta-aramid can maximize the flame retardancy and strength properties.

[0131] From the comparison of the data of Comparative Example 4 and Example 3, it can be seen that: if the concentration of the diisocyanate curing agent solution is too low, the interlayer peel strength of the fireproof and explosion-proof bag will be significantly reduced. Because the concentration of the diisocyanate curing agent solution is too low, during the coating process, more diisocyanate curing agent solution will be infiltrated into the fireproof layer, the thermal insulation layer, and the support layer, thereby affecting the adhesion effect between the layers. In addition, since the diisocyanate curing agent has infiltrated into the fireproof layer, the thermal insulation layer, and the support layer, the contribution of the para-aramid, silica-hydroxyl functionalized polyimide aerogel, and meta-aramid to flame retardancy and thermal insulation will also be reduced, ultimately affecting the comprehensive performance of the fireproof and explosion-proof bag.

[0132] From the comparison of the data of Comparative Example 5 and Example 3, it can be seen that if the concentration of the diisocyanate curing agent solution is too high, the thermal insulation performance of the fireproof and explosion-proof bag will be significantly reduced, because the high concentration of diisocyanate curing agent will block the holes in the silica-hydroxyl functionalized polyimide aerogel, which will eventually lead to the reduction of the flame retardant and thermal insulation performance of the fireproof and explosion-proof bag. Therefore, the use of the diisocyanate curing agent solution concentration defined in the present invention is more conducive to obtaining a fireproof and explosion-proof bag product with excellent fire resistance, thermal insulation, and interlayer bonding strength.

[0133] From the comparison of the data of Comparative Example 6 and Example 1, it can be seen that if the silica-hydroxyl functionalized polyimide aerogel is replaced with polyimide aerogel, the interlayer peel strength of the fire and explosion resistant bag is significantly reduced, the thermal shrinkage is significantly increased, and the high specific area structure cannot be effectively maintained at high temperature, thereby affecting the fire and explosion resistance of the fire and explosion resistant bag.

[0134] From the comparison of the data of Comparative Example 7 and Example 1, it can be seen that if no aromatic triamine is added during the preparation of the silica-hydroxyl functionalized polyimide aerogel, the thermal insulation performance and peel strength of the fireproof and explosion-proof bag will be significantly reduced, the high specific surface area will disappear, the heat cannot be effectively absorbed, and the contact points between the curing agent and the insulation layer will be sharply reduced, thereby affecting the thermal insulation performance and mechanical stability of the fireproof and explosion-proof bag.

[0135] From the comparison of the data of Comparative Example 8 and Example 1, it can be seen that if the silica-hydroxyl functionalized polyimide aerogel is replaced with hydroxyl functionalized polyimide aerogel, the thermal shrinkage of the fire and explosion resistant bag will increase significantly, and the high specific area structure cannot be effectively maintained at high temperature, thereby affecting the fire and explosion resistance of the fire and explosion resistant bag.

[0136] From the comparison of the data of Comparative Example 9 and Example 1, it can be seen that if the silica-hydroxyl functionalized polyimide aerogel is replaced with silica-polyimide aerogel, the reaction sites between the thermal insulation layer and the curing agent are reduced, and the interlayer peel strength of the fire and explosion resistant bag is significantly reduced, thereby affecting the fire and explosion resistant performance of the fire and explosion resistant bag.

[0137] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0138] For those skilled in the art, several modifications and improvements may be made without departing from the concept of the present invention, all of which belong to the protection scope of the present invention. The protection scope of the present invention shall be based on the attached claims.

Claims

1. A kind of aramid aerogel mobile phone fireproof and explosion-proof bag material, characterized in that: The fireproof and explosion-proof bag material comprises a fireproof layer, a heat insulation layer and a support layer from the inside to the outside; The fireproof layer is selected from at least one of meta-aramid and para-aramid; the heat insulation layer is silica-hydroxyl functionalized polyimide aerogel; the support layer is selected from at least one of meta-aramid and para-aramid; An isocyanate curing agent solution is coated between the layers of the fireproof and explosion-proof bag material. After the layers of material are compounded, they are heated and dried to obtain the fireproof and explosion-proof bag material.

2. According to claim 1, an aramid aerogel mobile phone fireproof and explosion-proof bag material is characterized in that: The preparation method of the silica-hydroxyl functionalized polyimide aerogel comprises the following steps: The aromatic dianhydride, the hydroxyl-functionalized aromatic diamine and the N-methylpyrrolidone solution are mixed to obtain a mixture, and the molar ratio of the aromatic dianhydride to the hydroxyl-functionalized diamine is controlled to be 10:(9-9.5); Adding an N-methylpyrrolidone solution of an aromatic triamine and a silica aerogel powder to the mixture, mixing them evenly, adding a dehydrating agent and a catalyst, mixing them evenly, processing and shaping them, and standing them to gel; the molar ratio of the aromatic triamine to the aromatic dianhydride is (0.35-0.7):10, and the molar ratio of the dehydrating agent to the aromatic dianhydride is (7-8):1; The gel is solvent exchanged in N-methylpyrrolidone and / or acetone solution for 1-5 days, dried by supercritical carbon dioxide, and vacuum dried at 40-80° C. to obtain a silicon dioxide-hydroxyl functionalized polyimide aerogel.

3. The silicon dioxide-hydroxyl functionalized polyimide aerogel according to claim 2, characterized in that: The aromatic dianhydride is selected from one or more of 3,3',4,4'-biphenyltetracarboxylic dianhydride, pyromellitic dianhydride, 3,3',4, 4'-diphenyl ether tetracarboxylic dianhydride, 3,3',4, 4'-dibenzophenone tetracarboxylic dianhydride, 3,3',4, 4'-triphenyl diether tetracarboxylic dianhydride, and 4,4'-(hexafluoroisopropyl) diphthalic dianhydride; The hydroxyl-functionalized aromatic diamine is 3,3'-dihydroxybenzidine; The aromatic triamine is selected from one or more of 1,3,5-triaminophenoxybenzene and 1,3,5-triaminobenzene; The dehydrating agent is acetic anhydride or propionic anhydride; The catalyst is selected from one or more of pyridine, isoquinoline and β-picoline; The silica aerogel powder has a particle size of 1-20 μm and a density of 0.1-0.12 g / cm 3 ; In the silica-hydroxyl functionalized polyimide aerogel, the mass proportion of silica aerogel powder is 10-40%, and the mass proportion of polyimide is 60-90%.

4. The aramid aerogel mobile phone fireproof and explosion-proof bag material according to claim 1, characterized in that: The isocyanate curing agent solution is a solution formed by dissolving an isocyanate curing agent in an organic solvent, the mass concentration of the isocyanate curing agent in the isocyanate curing agent solution is 15%-30%, and the functionality of the isocyanate group in the isocyanate curing agent is not less than 2; The organic solvent is any one of benzene, toluene, chlorobenzene, nitrobenzene and acetone.

5. The aramid aerogel mobile phone fireproof and explosion-proof bag material according to claim 1, characterized in that: The isocyanate curing agent is selected from at least one of diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, toluene diisocyanate, isophorone diisocyanate and triphenylmethane triisocyanate.

6. The aramid aerogel mobile phone fireproof and explosion-proof bag material according to claim 1, characterized in that: The thickness of the fireproof layer is 0.5-5 mm, the thickness of the heat insulation layer is 0.02-2 mm, and the thickness of the support layer is 0.5-5 mm.

7. The aramid aerogel mobile phone fireproof and explosion-proof bag material according to claim 1, characterized in that: The total mass of the fireproof and explosion-proof bag material is 100%, and the mass of the isocyanate curing agent is 0.1-5%.

8. The aramid aerogel mobile phone fireproof and explosion-proof bag material according to claim 1, characterized in that: The heating and drying process conditions are: heating temperature is 40-120° C., and vacuum drying is 12-48 hours.

9. A method for preparing an aramid aerogel mobile phone fireproof and explosion-proof bag material according to any one of claims 1 to 8, characterized in that: The preparation method is: coating an isocyanate curing agent solution on the support layer, and placing the heat insulating layer on the support layer coated with the isocyanate curing agent solution; Then, coating the isocyanate curing agent solution on the thermal insulation layer, placing the fireproof layer on the thermal insulation layer, and preparing a composite of the fireproof layer-thermal insulation layer-support layer; The composite of the fireproof layer-heat-insulating layer-support layer is heated and dried to obtain the aramid aerogel mobile phone fireproof and explosion-proof bag material.

10. An application of an aramid aerogel mobile phone fireproof and explosion-proof bag material according to any one of claims 1 to 8, characterized in that: The aramid aerogel mobile phone fireproof and explosion-proof bag material is used in the mobile phone fireproof and explosion-proof bag, the fireproof layer is used as the inner layer of the mobile phone fireproof and explosion-proof bag, and the support layer is used as the outer layer of the mobile phone fireproof and explosion-proof bag.

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