Flame-retardant and tear-resistant coating for airbag and preparation method thereof

Abstract

This application relates to the field of coatings, specifically disclosing a flame-retardant and tear-resistant coating for airbags and its preparation method. The flame-retardant and tear-resistant coating comprises the following raw materials in parts by weight: 50-80 parts polyurethane, 20-30 parts polysiloxane, 10-30 parts deionized water, 1.0-5.0 parts matting powder, 0.1-1.0 parts defoaming agent, 0.3-0.5 parts leveling agent, 1.0-5.0 parts dispersant, 5-15 parts flame retardant, 5-15 parts emulsifier, 0.5-2.5 parts anti-settling agent, and 5-15 parts filler, which includes intumescent flame retardant-coated hollow microspheres and coarsened thermal insulation fibers.

Description

Technical Field

[0001] The present application relates to the field of coatings, and more specifically, to a flame retardant and tear resistant coating for airbags and a preparation method thereof. Background Art

[0002] Airbags are passive safety devices installed in the driver's and passenger's seats, as well as in the front and rear seats, on the roof, and on the sides of the vehicle. In the event of a collision, a controller receives and processes signals from sensors, triggering an ignition signal to rapidly inflate and deploy the airbags, mitigating the impact on the driver and passengers. Therefore, airbags must possess excellent flame retardancy and tear resistance to provide reliable protection.

[0003] Existing airbag coatings typically use chloroprene rubber, but its flame retardancy is limited. Furthermore, it decomposes under high heat, producing toxic chloride gases. This creates an acidic environment for the base fabric, causing it to become brittle. Furthermore, chloroprene rubber is susceptible to aging in high-temperature environments due to reactions with strong oxidants. This can cause tears during rapid airbag deployment, rendering it ineffective in protecting the airbag. The development of a flame-retardant and tear-resistant coating to enhance the flame retardancy and tear resistance of airbags remains an unresolved issue. Summary of the Invention

[0004] In order to solve the problem of coatings being both flame retardant and tear resistant, the present application provides a flame retardant and tear resistant coating for airbags and a preparation method thereof.

[0005] In the first aspect, the present application provides a flame retardant and tear resistant coating for airbags, comprising the following raw materials in parts by weight: 50-80 parts of polyurethane dispersion, 20-30 parts of polysiloxane, 10-30 parts of deionized water, 1.0-5.0 parts of matting powder, 0.1-1.0 parts of defoaming agent, 0.3-0.5 parts of leveling agent, 1.0-5.0 parts of dispersant, 5-15 parts of flame retardant, 5-15 parts of emulsifier, 0.5-2.5 parts of anti-settling agent, and 5-15 parts of filler, wherein the filler includes intumescent flame retardant-coated hollow microspheres and coarsened thermal insulation fibers.

[0006] By adopting the above technical solution, the polyurethane has good adhesion, and the prepared coating is tightly adhered to the base fabric, which is conducive to fully exerting the performance of the flame-retardant and tear-resistant coating; polysiloxane can reduce the surface energy of the cured coating and also has good flame retardant properties. By adding a certain amount of polysiloxane, the prepared coating has soft and hard chain segments that are matched, has good adhesion to the base fabric, and is tear-resistant; by adding a certain amount of matting powder, defoaming agent, leveling agent, dispersant, emulsifier, and anti-settling agent, the prepared coating is more uniform and smooth; by adding a certain amount of flame retardant, the flame retardant properties of the coating are improved; the hollow microspheres have low thermal conductivity, light weight, and high specific strength, and are suitable for flame-retardant and tear-resistant coatings for airbags. They can provide good insulation, protect the base fabric, and ensure the stable use of the airbag. The thermal insulation fiber has good thermal insulation performance, high strength, and can conduct stress well. The resulting coating has good tear resistance. By coarsening the thermal insulation fiber, the surface of the fiber is rougher, forming a mechanical lock with the coating system, which is not easy to pull out, and the resulting coating is more tear-resistant. In addition, the coating will produce a certain amount of shrinkage during the curing process. The rough thermal insulation fiber can drive the coating matrix to move together. After curing, the resulting coating is smoother and denser, less likely to conduct heat, and has a good flame retardant effect. By adding a certain mass of intumescent flame retardant-coated hollow microspheres and coarsened thermal insulation fibers, the coarsened thermal insulation fibers are interspersed in the coating to form an insulation network. The intumescent flame retardant-coated hollow microspheres further provide insulation for the base fabric in the gaps between the coarsened thermal insulation fibers. The flame-retardant and tear-resistant coating provides more uniform and comprehensive protection for the base fabric. After the airbag is heated, the intumescent flame retardant expands into a porous foam coke layer, further filling the gap between the thermal insulation fibers and the hollow microspheres, isolating the transfer of heat from the outside. Moreover, the expanded intumescent flame retardant further fixes the adjacent crossed thermal insulation fibers together through the foam coke layer, making the thermal insulation fibers more difficult to pull out. The flame-retardant and tear-resistant coating obtained has good flame retardant and tear-resistant effects through the joint cooperation of thermal insulation fibers, hollow microspheres, and intumescent flame retardants.

[0007] Preferably, the silicon-oxygen bond content of the polysiloxane is 65-70%. At this time, the coating prepared has better adhesion, the components are more tightly combined, the shrinkage rate after curing is low, the thermal insulation network of the coating is more complete, the toughness is better and the tensile strength is higher, and it is not easy to crack during use.

[0008] In a specific embodiment, the mass ratio of the intumescent flame retardant coated hollow microspheres to the coarsened thermal insulation fibers is 1:(1.2-1.5).

[0009] By adopting the above technical solution, the cross-insulating network formed by the coarsened thermal insulation fibers in the prepared coating is evenly and tightly arranged, the hollow microbeads are fully filled in the pores formed by the intersection of the coarsened thermal insulation network, and the prepared coating insulation network has good thermal insulation effect. The hollow microbeads coated with the intumescent flame retardant can better fill the cross-spaces of the coarsened thermal insulation fibers, and the intumescent flame retardant can better coat the coarsened thermal insulation fibers. The prepared flame-retardant and tear-resistant coating has good flame retardant and tear-resistant performance.

[0010] In a specific embodiment, the hollow microspheres include one or more of fly ash hollow microspheres, glass hollow microspheres, and carbon hollow microspheres.

[0011] By adopting the above technical solution, the preparation of hollow microspheres is relatively convenient and simple, the thermal insulation effect is good, the heat resistance is good, the use effect is relatively stable, the weight is light, and it is suitable for use in flame retardant and tear resistant coatings.

[0012] In a specific embodiment, the roughened thermal insulation fibers are one or more of silicate fibers or glass fibers.

[0013] By adopting the above technical solution, the fiber has better heat resistance and heat insulation effects, is not easy to produce toxic gases after being heated, is beneficial to the health of users, and is suitable for use as a component of airbag coating.

[0014] In a specific embodiment, the intumescent flame retardant includes ammonium polyphosphate, melamine cyanuric acid and dipentaerythritol in a mass ratio of 7:4:3.

[0015] By adopting the above technical solution, the expansion and carbonization effects are good, the flame retardant performance is good, and the fixation effect on the insulation fibers and hollow microspheres is good. The prepared coating can stably maintain the insulation network after heating, has good flame retardant effect, the insulation fibers are not easy to pull out, and has good tear resistance.

[0016] In a specific embodiment, the steps of preparing the roughened thermal insulation fiber include:

[0017] S1: Add 35-45% of hydrogen fluoride to water, stir evenly, then add sodium sulfate, magnesium fluoride, and the balance of water, stir evenly to obtain a coarsening solution;

[0018] S2: Add the thermal insulation fiber to the roughening liquid prepared in S1, stir evenly, take out after 2-3 minutes, wash and dry to obtain roughened thermal insulation fiber.

[0019] By adopting the above technical solution, the thermal insulation fiber has a good coarsening effect, and the strength of the thermal insulation fiber is not significantly reduced. At the same time, uniform corrosion sites are formed on the surface of the thermal insulation fiber, and the prepared thermal insulation fiber is not easy to be pulled out in the system.

[0020] In a specific embodiment, the steps for preparing the intumescent flame retardant coated hollow microspheres include:

[0021] The hollow microspheres are added into 0.5-1 mol / L nitric acid and stirred for 0.5-1 hour, and vacuum filtered to obtain acidified hollow microspheres. The acidified hollow microspheres are added into a mixture of 2-3.5 wt% epoxy resin and 0.1-0.3 wt% epoxy resin curing agent, ultrasonically dispersed for 0.5-1.5 hours, vacuum filtered, and cured at room temperature for 8-24 hours to obtain pretreated hollow microspheres. The pretreated hollow microspheres are added into an intumescent flame retardant and stirred evenly to obtain intumescent flame retardant-coated hollow microspheres.

[0022] By adopting the above technical solution, the preparation process is simple, the intumescent flame retardant has a good coating effect on the hollow microspheres, the two are not easy to separate during the coating mixing process, and the hollow microspheres and the coarsened thermal insulation fibers can be fully fixed after expansion and carbonization.

[0023] In a specific embodiment, the intumescent flame retardant is organically modified.

[0024] By adopting the above technical solution, the compatibility of the intumescent flame retardant with the coating system is better, and the compatibility of the prepared intumescent flame retardant-coated hollow microspheres with the coating system is also better. They are evenly dispersed in the coating system and fully filled into the gaps formed by the intersection of the coarsened thermal insulation fibers. The flame retardant and tear-resistant coating obtained has more stable performance.

[0025] In a specific embodiment, the particle size of the hollow microbeads is 10-25 μm.

[0026] By adopting the above technical solution, the air cavity of the hollow microspheres is of moderate size and has low thermal conductivity. At the same time, at this particle size, they can be evenly distributed in the system and have good compatibility. The surface of the prepared coating is smooth and flat, and has a good filling effect on the thermal insulation network.

[0027] In a second aspect, the present application provides a method for preparing a flame retardant and tear resistant coating for an airbag, characterized in that the preparation method comprises the following steps:

[0028] S1: Stir polyurethane, defoamer, leveling agent, dispersant, and 60% of the formula amount of deionized water for 10-20 minutes at 300-500 rpm;

[0029] S2: Add the remaining ingredients in the formula and stir at a speed of 1500-2000 rpm for 30-35 minutes, then continue stirring at a low speed of 300-500 rpm for 10-20 minutes.

[0030] By adopting the above scheme, the preparation method is relatively simple, the components of the flame-retardant and tear-resistant coating are distributed more evenly, the formed coarsened thermal insulation fibers, hollow microspheres, and expandable flame retardant thermal insulation network work together effectively, the coarsened thermal insulation fibers are fully crossed, and the expandable flame retardant can effectively fix the coarsened thermal insulation fibers and hollow microspheres after expansion, so that the flame-retardant and tear-resistant coating has good flame retardant and tear-resistant effects.

[0031] In summary, this application has the following beneficial effects:

[0032] 1. The present application forms an insulation network by adding a certain mass of intumescent flame retardant-coated hollow microspheres and coarsened thermal insulation fibers as fillers. The intumescent flame retardant expands to further fill the gaps between the fibers and the hollow microspheres. The distribution of the insulation network is uniform and reasonable, and a better flame retardant effect can be obtained by adding less filler. The insulation network is fixed by coarsening the thermal insulation fibers and expanding the intumescent flame retardant. The fibers are not easily pulled out of the coating. The resulting coating has good tear resistance and can maintain good tear resistance even at high temperatures.

[0033] 2. In this application, by organically modifying the intumescent flame retardant and limiting the particle size of the hollow microspheres, the obtained intumescent flame retardant-coated hollow microspheres are better dispersed in the coating, more evenly distributed, and the formed insulation network has better insulation effect.

[0034] 3. The flame-retardant and tear-resistant coating prepared in this application is a water-based coating with low VOC, green and environmentally friendly, which can meet the health needs of users. It is suitable for use in airbags and can be directly sprayed on airbags. It is simple and convenient to use. DETAILED DESCRIPTION

[0035] The following is a more specific description of the technical solution of the present invention in combination with several specific implementation examples. The embodiments are only part of the embodiments of the present invention, not all of them. The following specific embodiments can be combined with each other, and the same or similar concepts or processes therein may not be repeated in some embodiments.

[0036] Unless otherwise specified, the experimental reagents in the preparation examples, embodiments, and comparative examples are conventional commercial brands or obtained through conventional preparation processes.

[0037] In the preparation examples, embodiments, and comparative examples: polyurethane was purchased from BASF; polysiloxane was MSE100 from Wacker, Germany; the defoamer was BYK-093; the leveling agent was BYK-348; the dispersant was SP-762 from Dongguan Xinbocheng Environmental Protection Materials; the matting powder was ED-30 from Nanofang Engineering Plastics; the flame retardant was JWN-MH-H02 from Ultra-Micro Nano New Materials; the emulsifier was Tween-80 from Haian Petrochemical; the anti-settling agent was fumed silica, purchased from Hubei Huifu Nano Materials HL380; the hollow microspheres were HN15HS from Hainuo Technology; and the polyoxypropylene diamine was D230.

[0038] Preparation Example

[0039] Preparation Example 1

[0040] Preparation of coarsened thermal insulation fibers

[0041] S1: Add 200 ml of hydrogen fluoride to 400 ml of water and stir evenly, then add 1.1 g of sodium sulfate, 1 g of magnesium fluoride, and 600 ml of water and stir evenly to obtain a coarsening solution;

[0042] S2: Add 200 g of glass fiber to the roughening solution prepared in S1, stir evenly, take out after 2 minutes, wash and dry to obtain roughened thermal insulation fiber.

[0043] Preparation Example 2

[0044] Preparation of roughened thermal conductive fibers

[0045] S1: Add 200 ml of hydrogen fluoride to 400 ml of water and stir evenly, then add 1.1 g of sodium sulfate, 1 g of magnesium fluoride, and 600 ml of water and stir evenly to obtain a coarsening solution;

[0046] S2: Add 200 g of carbon fiber to the roughening solution prepared in S1, stir evenly, take out after 2 minutes, wash and dry to obtain roughened thermal conductive fiber.

[0047] Preparation Example 3

[0048] Preparation of intumescent flame retardant coated hollow microspheres (25 μm)

[0049] S1: 70g of ammonium polyphosphate, 40g of melamine cyanuric acid, and 30g of dipentaerythritol were mixed to obtain an intumescent flame retardant. S2: 150g of hollow microspheres were added to 1000ml of 0.5mol / L nitric acid for 1 hour, vacuum filtered to obtain acidified hollow microspheres, the acidified hollow microspheres were added to 500ml of a mixture of 3.5wt% epoxy resin and 0.2wt% polyoxypropylene diamine, ultrasonically dispersed for 1 hour, vacuum filtered, and cured at room temperature for 24 hours to obtain pretreated hollow microspheres. The pretreated hollow microspheres were added to the intumescent flame retardant prepared in S1 and stirred to obtain intumescent flame retardant-coated hollow microspheres. The hollow microspheres in this preparation example were D10 from Hainuo Technology HN15HS, with a particle size of 25μm.

[0050] Preparation Example 4

[0051] Preparation of intumescent flame retardant coated hollow microspheres (55 μm)

[0052] The only difference between this preparation example and preparation example 3 is that the hollow microspheres are D50 of Hainuo Technology HN15HS, with a particle size of 55 μm.

[0053] Preparation Example 5

[0054] Preparation of hollow microspheres (25 μm) coated with organic intumescent flame retardant

[0055] S1: Add 250g of ethylene glycol to 100g of 0.1mol / L sodium hydroxide aqueous solution, stir evenly, add 140g of ammonium polyphosphate, then add 100g of 3-aminopropyltrimethoxysilane, stir evenly, heat to 100℃, react for 2 hours, filter, wash, and vacuum dry to obtain modified ammonium polyphosphate. The obtained modified ammonium polyphosphate is mixed evenly with 80g of melamine cyanuric acid and 60g of dipentaerythritol to obtain an organic flame retardant.

[0056] S2: 150g of hollow microspheres were placed in 1000ml of 0.5mol / L nitric acid for 1 hour, vacuum filtered to obtain acidified hollow microspheres, and the acidified hollow microspheres were placed in 500ml of a mixture of 3.5wt% epoxy resin and 0.2wt% polyoxypropylene diamine, ultrasonically dispersed for 1 hour, vacuum filtered, and cured at room temperature for 24 hours to obtain pretreated hollow microspheres. The pretreated hollow microspheres were placed in 140g of the organic flame retardant prepared in S1 and stirred to obtain intumescent flame retardant-coated hollow microspheres. The hollow microspheres in this preparation example were D10 from Hainuo Technology HN15HS, with a particle size of 25μm.

[0057] Example

[0058] Example 1

[0059] This preparation example includes the following raw materials by weight: 500g of polyurethane, 300g of polysiloxane, 300g of deionized water, 30g of matting powder, 10g of defoaming agent, 3g of leveling agent, 20g of dispersant, 60g of emulsifier, 10g of anti-settling agent, 50g of flame retardant, and 132g of filler, wherein the filler includes 60g of intumescent flame retardant-coated hollow microspheres prepared in Preparation Example 3 and 72g of roughened thermal insulation fiber prepared in Preparation Example 1.

[0060] S1: Stir polyurethane, defoamer, leveling agent, dispersant, and 60% of the formula amount of deionized water for 15 minutes at 300 rpm;

[0061] S2: Add the remaining ingredients, stir at 1500 rpm for 30 minutes, and then continue stirring at a low speed of 500 rpm for 10 minutes.

[0062] Example 2

[0063] The difference between this preparation example and preparation example 1 is that it includes the following raw materials by weight: 700g of polyurethane, 300g of polysiloxane, 300g of deionized water, 50g of matting powder, 10g of defoaming agent, 5g of leveling agent, 50g of dispersant, 60g of emulsifier, 10g of anti-settling agent, 100g of flame retardant, and 66g of filler, wherein the filler includes 30g of intumescent flame retardant-coated hollow microspheres prepared in preparation example 3 and 36g of roughened thermal insulation fiber prepared in preparation example 1.

[0064] Example 3

[0065] The difference between this preparation example and preparation example 1 is that it includes the following raw materials by weight: 800g of polyurethane, 200g of polysiloxane, 300g of deionized water, 50g of matting powder, 10g of defoaming agent, 5g of leveling agent, 50g of dispersant, 60g of emulsifier, 10g of anti-settling agent, 100g of flame retardant, and 66g of filler, wherein the filler includes 30g of intumescent flame retardant-coated hollow microspheres prepared in preparation example 3 and 36g of roughened thermal insulation fiber prepared in preparation example 1.

[0066] Example 4

[0067] The difference between this preparation example and preparation example 1 is that it includes the following raw materials by weight: 500g of polyurethane, 300g of polysiloxane, 300g of deionized water, 30g of matting powder, 10g of defoaming agent, 3g of leveling agent, 20g of dispersant, 60g of emulsifier, 10g of anti-settling agent, 50g of flame retardant, and 132g of filler, wherein the filler includes 52.8g of intumescent flame retardant-coated hollow microspheres prepared in preparation example 3 and 79.2g of roughened thermal insulation fiber prepared in preparation example 1.

[0068] Example 5

[0069] This preparation example includes the following raw materials in parts by weight: 500g of polyurethane, 300g of polysiloxane, 300g of deionized water, 30g of matting powder, 10g of defoaming agent, 3g of leveling agent, 20g of dispersant, 60g of emulsifier, 10g of anti-settling agent, 50g of flame retardant, and 132g of filler, wherein the filler includes 66g of intumescent flame retardant-coated hollow microspheres prepared in Preparation Example 3 and 66g of roughened thermal insulation fiber prepared in Preparation Example 1.

[0070] Example 6

[0071] This preparation example includes the following raw materials in parts by weight: 500g of polyurethane, 300g of polysiloxane, 300g of deionized water, 30g of matting powder, 10g of defoaming agent, 3g of leveling agent, 20g of dispersant, 60g of emulsifier, 10g of anti-settling agent, 50g of flame retardant, and 132g of filler, wherein the filler includes 60g of intumescent flame retardant-coated hollow microspheres prepared in Preparation Example 4 and 72g of roughened thermal insulation fiber prepared in Preparation Example 1.

[0072] Example 7

[0073] This preparation example includes the following raw materials in parts by weight: 500g of polyurethane, 300g of polysiloxane, 300g of deionized water, 30g of matting powder, 10g of defoaming agent, 3g of leveling agent, 20g of dispersant, 60g of emulsifier, 10g of anti-settling agent, 50g of flame retardant, and 132g of filler, wherein the filler includes 60g of organic intumescent flame retardant-coated hollow microspheres prepared in Preparation Example 5 and 72g of roughened thermal insulation fiber prepared in Preparation Example 1.

[0074] Comparative Example

[0075] Comparative Example 1

[0076] This comparative example includes the following raw materials in parts by weight: 400g of polyurethane, 400g of polysiloxane, 300g of deionized water, 30g of matting powder, 10g of defoaming agent, 3g of leveling agent, 20g of dispersant, 60g of emulsifier, 10g of anti-settling agent, 180g of flame retardant, and 132g of filler, wherein the filler includes 60g of intumescent flame retardant-coated hollow microspheres prepared in Preparation Example 3 and 72g of roughened thermal insulation fiber prepared in Preparation Example 1.

[0077] S1: Stir polyurethane, defoamer, leveling agent, dispersant, and 60% of the formula amount of deionized water for 15 minutes at 300 rpm;

[0078] S2: Add the remaining ingredients, stir at 1500 rpm for 30 minutes, and then continue stirring at a low speed of 500 rpm for 10 minutes.

[0079] Comparative Example 2

[0080] This comparative example includes the following raw materials in parts by weight: 500g of polyurethane, 300g of polysiloxane, 300g of deionized water, 30g of matting powder, 10g of defoaming agent, 3g of leveling agent, 20g of dispersant, 60g of emulsifier, 10g of anti-settling agent, 50g of flame retardant, and 132g of filler, wherein the filler includes 60g of intumescent flame retardant-coated hollow microspheres prepared in Preparation Example 3 and 72g of roughened thermal conductive fibers prepared in Preparation Example 2.

[0081] S1: Stir polyurethane, defoamer, leveling agent, dispersant, and 60% of the formula amount of deionized water for 15 minutes at 300 rpm;

[0082] S2: Add the remaining ingredients, stir at 1500 rpm for 30 minutes, and then continue stirring at a low speed of 500 rpm for 10 minutes.

[0083] Performance testing

[0084] The coatings prepared in the examples and comparative examples were tested in the first test: with reference to the standard "GB / T8626-88 Test method for flammability of building materials", the flame retardant and tear resistant coatings prepared in each example and comparative example were coated with a 200 μm thick film cured at 70°C and the combustion performance was tested. The grades obtained were A (non-combustible), B1 (difficult to burn), B2 (combustible) and B3 (combustible) from high to low; the test results are shown in Table 1.

[0085] Test 2: Referring to the standard "GB / T 10654 Determination of tensile strength and elongation at break of polymer porous elastic materials", the flame retardant and tear resistant coatings prepared in each embodiment and comparative example were coated with a 200 μm thick film cured at 70°C and subjected to a tensile strength test; the test results are shown in Table 1.

[0086] Table 1

[0087] Flame retardant grade Tensile strength (MPa) Example 1 B1 (flame retardant) 1.84 Example 2 B1 (flame retardant) 1.81 Example 3 B1 (flame retardant) 1.80 Example 4 B1 (flame retardant) 1.97 Example 5 B2(flammable) 1.92 Example 6 B1 (flame retardant) 1.82 Example 7 A (non-flammable) 1.95 Comparative Example 1 B2(flammable) 1.74 Comparative Example 2 B3 (flammable) 1.85

[0088] In combination with Examples 1-3 and Comparative Examples 1-2, the present application adds intumescent flame retardant-coated hollow microspheres and coarsened thermal insulation fibers to the polyurethane and polysiloxane system and limits the mass ratio of each component, so that the coating obtained has good flame retardant properties and high tensile strength.

[0089] In combination with Example 1 and Implementations 4-5, the present application limits the mass of the intumescent flame retardant-coated hollow microspheres and the coarsened thermal insulation fibers to a certain ratio, so that the obtained coating has a better thermal insulation network construction effect, and the thermal insulation fibers are more tightly bonded, and the flame retardant level and tensile strength of the obtained coating are better.

[0090] In combination with Example 1 and Example 6, this application limits the particle size of the hollow microspheres, so that the obtained coating is more evenly dispersed, fully exerts the thermal insulation effect of the hollow microspheres and the thermal insulation fibers, and better conducts the stress of the fibers, so that the obtained coating has a better flame retardant level and tensile strength.

[0091] In combination with Example 1 and Example 7, the present application makes the intumescent flame retardant organic, so that the flame retardant drives the coated hollow microspheres to be more evenly dispersed and has better compatibility, and the prepared coating has better flame retardancy and tensile strength.

[0092] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A flame retardant and tear resistant coating for airbags, characterized by: The flame retardant and tear resistant coating comprises the following raw materials in parts by weight: 50-80 parts of polyurethane, 20-30 parts of polysiloxane, 10-30 parts of deionized water, 1.0-5.0 parts of matting powder, 0.1-1.0 parts of defoaming agent, 0.3-0.5 parts of leveling agent, 1.0-5.0 parts of dispersant, 5-15 parts of flame retardant, 5-15 parts of emulsifier, 0.5-2.5 parts of anti-settling agent, and 5-15 parts of filler, wherein the filler comprises hollow microspheres coated with intumescent flame retardant and roughened thermal insulation fiber; The particle size of the hollow microspheres is 10-25 μm; The preparation steps of the roughened thermal insulation fiber include: S1: Add hydrogen fluoride to 35-45% of the formula amount of water, stir evenly, then add sodium sulfate, magnesium fluoride, and the balance of water, stir evenly to obtain a coarsening solution; S2: Add the thermal insulation fiber to the roughening liquid prepared in S1, stir evenly, take out after 2-3 minutes, wash and dry to obtain roughened thermal insulation fiber; The preparation steps of the intumescent flame retardant coated hollow microspheres include: The hollow microspheres are added into 0.5-1 mol / L nitric acid and stirred for 0.5-1 hour, and vacuum filtered to obtain acidified hollow microspheres. The acidified hollow microspheres are added into a mixture of 2-3.5 wt% epoxy resin and 0.1-0.3 wt% epoxy resin curing agent, ultrasonically dispersed for 0.5-1.5 hours, vacuum filtered, and cured at room temperature for 8-24 hours to obtain pretreated hollow microspheres. The pretreated hollow microspheres are added into an intumescent flame retardant and stirred evenly to obtain intumescent flame retardant-coated hollow microspheres.

2. The flame retardant and tear resistant coating for airbags according to claim 1, characterized in that: The mass ratio of the intumescent flame retardant coated hollow microspheres to the coarsened thermal insulation fibers is 1:(1.2-1.5).

3. The flame retardant and tear resistant coating for airbags according to claim 1, characterized in that: The hollow microspheres include one or more of fly ash hollow microspheres, glass hollow microspheres, and carbon hollow microspheres.

4. The flame retardant and tear resistant coating for airbags according to claim 1, characterized in that: The roughened thermal insulation fibers are one or more of silicate fibers and glass fibers.

5. The flame retardant and tear resistant coating for airbags according to claim 1, characterized in that: The intumescent flame retardant comprises ammonium polyphosphate, melamine cyanuric acid and dipentaerythritol in a mass ratio of 7:4:

3.

6. The flame retardant and tear resistant coating for airbags according to claim 5, characterized in that: The ammonium polyphosphate is organically modified.

7. A method for preparing the flame-retardant and tear-resistant coating for airbags according to any one of claims 1 to 6, characterized in that: The preparation method comprises the following steps: S1: Stir polyurethane, defoamer, leveling agent, dispersant, and 60% of the formula amount of deionized water for 10-20 minutes at 300-500 rpm; S2: Add the remaining ingredients in the formula and stir at a speed of 1500-2000 rpm for 30-35 minutes, then continue stirring at a low speed of 300-500 rpm for 10-20 minutes.