Flame-retardant modified asphalt waterproof coiled material and preparation method thereof
By using a five-layer flame-retardant modified bitumen waterproof membrane, which combines styrene-butadiene-styrene copolymer and composite flame retardant, the problem of insufficient flame-retardant and mechanical properties of existing flame-retardant modified bitumen waterproof membranes is solved, achieving efficient flame-retardant effect and excellent aging resistance.
Patent Information
- Application Number
- CN202511168433.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-20
- Publication Date
- 2025-11-07
AI Technical Summary
Existing flame-retardant modified bitumen waterproof membranes have shortcomings in terms of flame retardant performance and mechanical properties. In particular, the inorganic flame retardants have poor compatibility and the organic flame retardants are prone to migration, resulting in poor long-term flame retardant effect and insufficient aging resistance.
The flame-retardant modified bitumen waterproof membrane adopts a five-layer structure. By adding styrene-butadiene-styrene copolymer, carbon nanotubes and composite flame retardants to the 70# bitumen matrix, and treating the inorganic flame retardant with a bio-based silane coupling agent, a multi-flame-retardant system is formed, which enhances compatibility and dispersibility. Furthermore, the mechanical properties and high-temperature stability are improved by constructing a cross-linked network through isocyanate.
It improves the limiting oxygen index to 33.6-34.1%, tensile strength to 597-606 N/mm, elongation at break to 475-486%, tear strength to 181-187 N/mm, and seam peel strength to 3.76-3.93 N/mm. It has excellent aging resistance, does not flow or drip at high temperatures, and does not crack at low temperatures.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of waterproofing membranes, and particularly relates to a flame-retardant modified bitumen waterproofing membrane and a preparation method thereof. BACKGROUND
[0002] Waterproofing membranes are mainly used for building walls, roofs, tunnels, highways, landfills, etc., and are a flexible building material product that can be rolled into a roll to resist external rainwater and groundwater seepage. As the impermeable connection between the engineering foundation and the building, waterproofing membranes are the first barrier of the entire engineering waterproofing and play a crucial role in the entire project.
[0003] Currently, waterproofing membranes mainly include modified bitumen waterproofing membranes, self-adhesive waterproofing membranes, and high polymer waterproofing membranes, etc. Among them, modified bitumen waterproofing membranes are widely used due to their good flexibility, weather resistance, and waterproofing performance. However, bitumen itself is a flammable material. During combustion, bitumen will first melt, drip, and flow, and then the molten beads will start to burn. The burning molten beads will continue to drip and flow, causing the fire to spread rapidly. In addition, bitumen releases a large amount of toxic gas during combustion, which can fuel the fire and produce a large amount of smoke, making it difficult to extinguish the fire. Therefore, it is of great significance to research modified bitumen waterproofing membranes with excellent flame-retardant performance.
[0004] In the prior art, when preparing flame-retardant modified bitumen waterproofing membranes, a method of adding flame retardants is usually used. Common flame retardants include inorganic flame retardants and organic flame retardants. Inorganic flame retardants include aluminum hydroxide, magnesium hydroxide, etc., and organic flame retardants include halogen-based flame retardants, nitrogen-based flame retardants, etc. However, the following problems may exist: Inorganic flame retardants have poor compatibility with bitumen. During the preparation and use process, phase separation may occur, which may reduce the mechanical properties such as tensile strength of the waterproofing membrane. Moreover, the single flame-retardant mechanism has limited flame-retardant effect. Although organic flame retardants have relatively good compatibility with the bitumen matrix, they are prone to migration. With the passage of time, the flame retardant may migrate from the bitumen, thereby reducing the flame-retardant performance of the waterproofing membrane and failing to meet the long-term flame-retardant effect.
[0005] CN118496779A discloses a kind of flame-retardant asphalt-based waterproofing membrane, the preparation steps of the flame-retardant asphalt-based waterproofing membrane are as follows: heating asphalt to 190-200℃, after stirring uniformly, cooling to 180-190℃, adding styrene-butadiene-styrene block copolymer, heating to 190-200℃, stirring, adding tackifying resin and waste rubber powder, after heat preservation and stirring, adding modified hexagonal boron nitride, continue heat preservation and stirring, to get mixed material;Mixed material is extruded after melting, then it is pressed into sheet, then it is cooled, trimmed, pulled and rolled to get the flame-retardant asphalt-based waterproofing membrane;Among them, the modified hexagonal boron nitride is treated on the surface of boron nitride by using silane coupling agent kH550 and phytic acid, then titanium dioxide is obtained by chemical reaction of ammonium hexafluorotitanate and boric acid, which is attached to the surface of boron nitride by chelation, so as to improve the flame-retardant performance and reduce the smoke generated during combustion.
[0006] The waterproofing membrane has excellent flame-retardant performance, high peel strength, and certain antifouling and sterilization effect, and the oxygen index is 28-31%, and the peel strength is 2.3-2.5 N / mm, but the oxygen index is still low, and the tensile strength and other mechanical properties are poor, and the aging resistance is poor. SUMMARY
[0007] To solve the technical problems existing in the prior art, the present application provides a flame-retardant modified asphalt waterproofing membrane, which improves the flame-retardant performance, ensures the mechanical properties, enhances the waterproofing performance, and improves the aging resistance of the waterproofing membrane.
[0008] The present application provides a flame-retardant modified asphalt waterproofing membrane and a preparation method thereof, which are as follows: A preparation method of a flame-retardant modified asphalt waterproofing membrane is to coat flame-retardant modified asphalt material on both sides of a base layer to obtain an upper flame-retardant modified asphalt layer and a lower flame-retardant modified asphalt layer, cover polyethylene film on both sides of the flame-retardant modified asphalt layer to obtain an upper protective layer and a lower protective layer, and obtain the flame-retardant modified asphalt waterproofing membrane by hot pressing and cooling. The flame-retardant modified asphalt waterproofing membrane has an upper protective layer, an upper flame-retardant modified asphalt layer, a base layer, a lower flame-retardant modified asphalt layer, and a lower protective layer from top to bottom. The base layer is a polyester fiber non-woven fabric with a thickness of 0.20-0.25 mm. The coating thickness of the flame-retardant modified asphalt material is 1.2-1.4 mm. The thickness of the polyethylene film is 0.18-0.23 mm.
[0009] The preparation method of the flame-retardant modified asphalt material is that 70# asphalt is added into a closed container, the temperature is raised to 162-167℃, stirring is carried out at 280-310 rpm for 27-32 min, styrene-butadiene-styrene copolymer is added, the temperature is raised to 175-180℃, shear dispersion is carried out at 2000-2300 rpm for 18-22 min, naphthenic oil is added for the first time, shear dispersion is continuously carried out for 23-27 min, carbon nanotubes are added, the temperature is reduced to 168-172℃, stirring is carried out at 1100-1300 rpm for 37-45 min, then the temperature is reduced to 140-144℃, asphalt modifier is added, stirring is carried out at 610-640 rpm for 38-45 min, composite flame retardant is added, heat preservation stirring is carried out for 32-40 min, naphthenic oil is added for the second time, heat preservation stirring is carried out for 27-32 min, isophorone diisocyanate is finally added, stirring is carried out at 128-133℃ for 38-43 min, and the flame-retardant modified asphalt material is obtained; The particle size of the carbon nanotubes is 80-110 nm; The mass ratio of the 70# asphalt, styrene-butadiene-styrene copolymer, naphthenic oil added for the first time, carbon nanotubes, asphalt modifier, composite flame retardant, naphthenic oil added for the second time, and isophorone diisocyanate is 100:4.0-4.5:1.8-2.2:4.8-5.3:8.7-9.2:6.2-6.7:1.8-2.2:2.4-2.6.
[0010] The preparation method of the asphalt modifier is that epoxy soybean oil is added into a closed container, then methyl tetrahydrophthalic anhydride is added, after uniform stirring, under a nitrogen atmosphere, tetrabutylammonium bromide is added while stirring, the stirring speed is 280-310 rpm, after the addition is completed, the temperature is raised to 82-87℃, stirring is carried out at 460-510 rpm for 78-83 min of reaction, after the reaction is completed, after cooling and filtration, the asphalt modifier is obtained; The mass ratio of the epoxy soybean oil, methyl tetrahydrophthalic anhydride, and tetrabutylammonium bromide is 18-23:3.7-4.0:0.10-0.14.
[0011] The preparation method of the composite flame retardant comprises mixing and compounding steps; The mixing step is that magnesium hydroxide and ammonium polyphosphate are added into anhydrous ethanol, the temperature is raised to 48-52℃, stirring is carried out for 27-32 min, then bio-based silane coupling agent is added, heat preservation stirring is carried out for 58-65 min, and the flame retardant is obtained; The mass ratio of the magnesium hydroxide, sodium polyphosphate, anhydrous ethanol, and bio-based silane coupling agent is 4.0-4.4:6.0-6.5:100:1.5-1.8.
[0012] The compounding step is that deionized water is added to graphene, ultrasonic dispersion is carried out, the ultrasonic power is controlled to be 360-380 W, the ultrasonic frequency is controlled to be 27-32 kHz, the ultrasonic time is controlled to be 25-35 min, after the ultrasonic ends, a flame retardant is added, the temperature is increased to 48-52 DEG C, stirring is carried out at 670-720 rpm for 1.8-2.2 h, the temperature is increased to 70-75 DEG C, then the temperature of the maleic anhydride grafted polyethylene solution is reduced to 70-75 DEG C, the maleic anhydride grafted polyethylene solution is added, and stirring is carried out at 240-260 rpm for 1.0-1.3 h, to obtain a composite flame retardant; The mass ratio of the graphene, the deionized water, the flame retardant, the maleic anhydride grafted polyethylene solution is 6.2-6.5:68-75:10.2-10.7:3.0-3.4; The maleic anhydride grafted polyethylene solution is a mixed solution of maleic anhydride grafted polyethylene and dimethylbenzene at 112-117 DEG C, and the mass ratio of the maleic anhydride grafted polyethylene and dimethylbenzene is 5.5:24.5-28.5; The maleic anhydride grafted polyethylene has a melt index of 10-13 g / 10 min under the condition of 180 DEG C and 2.16 kg.
[0013] The preparation method of the bio-based silane coupling agent is that castor oil acid and gamma-aminopropyl triethoxysilane are added to a closed container, stirring is carried out at 330-370 rpm for 13-20 min under nitrogen protection, then amino sulfonic acid is added, the temperature is increased to 78-82 DEG C at a rate of 1.8-2.2 DEG C / min, and stirring is carried out under heat preservation for 18-25 min, then the temperature is increased to 102-107 DEG C at a rate of 0.8-1.2 DEG C / min, and reaction is carried out under heat preservation for 1.7-2.2 h, after the reaction ends, filtration, washing and drying are carried out, and the bio-based silane coupling agent is obtained; The mass ratio of the castor oil acid, the gamma-aminopropyl triethoxysilane and the amino sulfonic acid is 8.2-8.6:3.8-4.2:0.13-0.16.
[0014] A flame-retardant modified asphalt waterproof coiled material is prepared by the foregoing preparation method.
[0015] The structure of the fire-retardant modified asphalt waterproof coiled material of the present application is five layers, and through the synergistic effect between the components, the mechanical properties are ensured while the fire-retardant properties are improved, and the waterproof performance and aging resistance are enhanced; wherein the upper and lower fire-retardant modified asphalt layers are mainly formed by the fire-retardant modified asphalt material, the fire-retardant modified asphalt material is based on 70# asphalt as the base body, through the addition of styrene-butadiene-styrene copolymer, the rigid structure and flexible structure are introduced at the same time, the low-temperature flexibility is ensured while the high-temperature resistance is enhanced, the compatibility of the asphalt modifier and the asphalt system is good, the balance of the flexible chain segment and the rigid chain segment is further optimized, the synergistic composite fire-retardant agent is ensured, the dispersion performance in the asphalt system is ensured, through the addition of naphthenic oil twice, the viscosity of the system is effectively adjusted, the isocyanate can be firmly combined with the asphalt, the crosslinking network is constructed, the waterproof performance is enhanced, the fire-retardant properties of the fire-retardant modified asphalt material are improved, and the mechanical properties and high-temperature stability are improved.
[0016] Specifically, the asphalt modifier is combined by epoxy soybean oil and methyl tetrahydrophthalic anhydride under the action of tetrabutylammonium bromide to introduce flexible long-chain to enhance low-temperature flexibility, and the anhydride can improve high-temperature stability as a rigid structure, and the compatibility of the anhydride and the styrene-butadiene-styrene copolymer is good, which promotes the formation of interpenetrating network structure and enhances aging resistance. Specifically, the composite fire-retardant agent is obtained by compounding magnesium hydroxide and ammonium polyphosphate as the fire-retardant agent, then treated by the bio-based organosilane coupling agent, and then compounded with graphene; in the mixing step, the bio-based silane coupling agent is combined with the fire-retardant agent components, the bio-based silane coupling agent is chemically combined by using amino silane coupling agent and castor oil acid as raw materials under the catalytic action, the obtained bio-based silane coupling agent is used as a bridging agent to enhance the compatibility of magnesium hydroxide, ammonium polyphosphate and the like with asphalt, improve the dispersibility in the asphalt system, and further improve the fire-retardant properties while ensuring the mechanical properties; in the compounding step, the sheet structure of graphene can form a physical barrier layer to better play the fire-retardant properties, the combination of maleic anhydride grafted polyethylene, the combination of maleic anhydride and graphene hydroxyl, and the good compatibility of the polyethylene segment with asphalt further enhance the dispersibility in the asphalt system, and finally the obtained composite fire-retardant agent forms a multiple fire-retardant system, which can not only enhance the fire-retardant properties, but also improve the mechanical properties and stability. Compared with the prior art, the present application has the following beneficial effects:
[0017] 1. The fire-retardant modified asphalt waterproof coiled material prepared by the present application has a water pressure of 0.2 MPa, and is maintained for 2 hours, and is maintained for 30 minutes every 0.01 MPa, and water permeation occurs at 0.64-0.67 MPa; 2. The fire-retardant modified asphalt waterproof coiled material prepared by the present application has an ultimate oxygen index of 33.6-34.1%; 3. The prepared flame-retardant modified asphalt waterproofing membrane has a tensile strength of 597-606 N / mm, an elongation at break of 475-486%, a tear strength of 181-187 N, a seam peeling strength of 3.76-3.93 N / mm, no flow and no dripping for 2.0 h at 118-123℃, and no cracks at -32.0 to -33.4℃. 3. The prepared flame-retardant modified asphalt waterproofing membrane has a tensile strength of 572-584 N / mm, an elongation at break of 456-471%, a tear strength of 173-180 N, a seam peeling strength of 3.58-3.76 N / mm, and no cracks at -30.3 to -31.9℃ after being placed in an environment with a temperature of 70℃ and a humidity of 65% for 10 d, and then being irradiated with a UV irradiation intensity of 0.8 W / cm 2 , a temperature of 40℃ for 10 d. DETAILED DESCRIPTION
[0018] In order to more clearly understand the technical features, objectives and effects of the present application, the specific embodiments of the present application will be described below. Example 1
[0019] A preparation method of a flame-retardant modified asphalt waterproofing membrane comprises the following steps: coating a flame-retardant modified asphalt material on both sides of a base layer to obtain an upper flame-retardant modified asphalt layer and a lower flame-retardant modified asphalt layer, covering a polyethylene film on both sides of the flame-retardant modified asphalt layers to obtain an upper protective layer and a lower protective layer, and obtaining the flame-retardant modified asphalt waterproofing membrane through hot pressing and cooling. The flame-retardant modified asphalt waterproofing membrane has an upper protective layer, an upper flame-retardant modified asphalt layer, a base layer, a lower flame-retardant modified asphalt layer, and a lower protective layer from top to bottom. The base layer is a polyester fiber non-woven fabric with a thickness of 0.20 mm. The coating thickness of the flame-retardant modified asphalt material is 1.2 mm. The thickness of the polyethylene film is 0.18 mm.
[0020] The preparation method of the flame-retardant modified asphalt material is as follows: 100 g of 70# asphalt is added into a closed container, the temperature is raised to 162 DEG C, stirring is carried out at 280 rpm for 27 min, 4.0 g of styrene-butadiene-styrene copolymer is added, the temperature is raised to 175 DEG C, shearing dispersion is carried out at 2000 rpm for 22 min, 1.8 g of naphthenic oil is added, shearing dispersion is continuously carried out for 23 min, 4.8 g of carbon nanotubes is added, the temperature is reduced to 168 DEG C, stirring is carried out at 1100 rpm for 45 min, then the temperature is reduced to 140 DEG C, 8.7 g of asphalt modifier is added, stirring is carried out at 610 rpm for 45 min, 6.2 g of composite flame retardant is added, temperature-stirring is carried out for 40 min, then 1.8 g of naphthenic oil is added, temperature-stirring is carried out for 32 min, finally 2.4 g of isofuroate diisocyanate is added, stirring is carried out at 128 DEG C for 43 min, and the flame-retardant modified asphalt material is obtained; The particle size of the carbon nanotubes is 80 nm.
[0021] The preparation method of the asphalt modifier is as follows: 18 g of epoxy soybean oil is added into a closed container, then 3.7 g of methyl tetrahydrophthalic anhydride is added, after uniform stirring, 0.10 g of tetrabutylammonium bromide is added under nitrogen atmosphere while stirring, the stirring speed is 280 rpm, after the addition is completed, the temperature is raised to 82 DEG C, and stirring is carried out at 460 rpm for 78 min, after the reaction is completed, filtration is carried out after cooling, and the asphalt modifier is obtained.
[0022] The preparation method of the composite flame retardant comprises mixing and compounding steps. The mixing step is as follows: 4.0 g of magnesium hydroxide and 6.0 g of ammonium polyphosphate are added into 100 g of anhydrous ethanol, the temperature is raised to 48 DEG C, stirring is carried out for 32 min, then 1.5 g of bio-based silane coupling agent is added, and temperature-stirring is carried out for 65 min, and the flame retardant is obtained. The compounding step is as follows: 68 g of deionized water is added into 6.2 g of graphene, ultrasonic dispersion is carried out, the ultrasonic power is controlled to be 360 W, the ultrasonic frequency is 32 kHz, the ultrasonic time is 35 min, after the ultrasonic is completed, 10.2 g of the flame retardant is added, the temperature is raised to 48 DEG C, and stirring is carried out at 670 rpm for 2.2 h, the temperature is raised to 70 DEG C, then the temperature of the maleic anhydride grafted polyethylene solution is reduced to 70 DEG C, 3.0 g of maleic anhydride grafted polyethylene solution is added, and stirring is carried out at 240 rpm for 1.3 h, and the composite flame retardant is obtained. The maleic anhydride grafted polyethylene solution is a mixed solution of maleic anhydride grafted polyethylene and xylene at 112 DEG C, and the mass ratio of the maleic anhydride grafted polyethylene to xylene is 5.5:24.5. The melt index of the maleic anhydride grafted polyethylene is 10 g / 10 min under the condition of 180 DEG C and 2.16 kg. The preparation method of the bio-based silane coupling agent is that 8.2 g of castor oil acid and 3.8 g of gamma-aminopropyl triethoxysilane are added into a closed container, stirred at 330 rpm for 20 min under nitrogen protection, then 0.13 g of sulfamic acid is added, the temperature is increased to 78 ℃ at a rate of 1.8 ℃ / min, and stirred for 25 min, then the temperature is increased to 102 ℃ at a rate of 0.8 ℃ / min, and reacted for 2.2 h, after the reaction is completed, filtration, washing and drying are carried out, and the bio-based silane coupling agent is obtained. Example 2
[0023] A preparation method of a flame-retardant modified asphalt waterproof coiled material is that a flame-retardant modified asphalt material is coated on both sides of a base layer to obtain an upper flame-retardant modified asphalt layer and a lower flame-retardant modified asphalt layer, polyethylene films are covered on both sides of the flame-retardant modified asphalt layers to obtain an upper protective layer and a lower protective layer, and a flame-retardant modified asphalt waterproof coiled material is obtained through hot pressing and cooling. The flame-retardant modified asphalt waterproof coiled material has an upper protective layer, an upper flame-retardant modified asphalt layer, a base layer, a lower flame-retardant modified asphalt layer and a lower protective layer from top to bottom. The base layer is a polyester fiber non-woven fabric with a thickness of 0.22 mm. The coating thickness of the flame-retardant modified asphalt material is 1.3 mm. The thickness of the polyethylene film is 0.20 mm.
[0024] The preparation method of the flame-retardant modified asphalt material is that 100 g of 70# asphalt is added into a closed container, the temperature is increased to 165 ℃, and stirred at 300 rpm for 30 min, then 4.2 g of styrene-butadiene-styrene copolymer is added, the temperature is increased to 178 ℃, and shearing dispersion is carried out at 2200 rpm for 20 min, then 2.0 g of naphthenic oil is added, and shearing dispersion is carried out for another 25 min, then 5.0 g of carbon nanotubes is added, the temperature is decreased to 170 ℃, and stirred at 1200 rpm for 40 min, then the temperature is decreased to 142 ℃, 9.0 g of asphalt modifier is added, and stirred at 620 rpm for 40 min, then 6.5 g of composite flame retardant is added, and stirred for 35 min, then 2.0 g of naphthenic oil is added, and stirred for 30 min, finally 2.5 g of isophorone diisocyanate is added, and stirred at 132 ℃ for 40 min to obtain the flame-retardant modified asphalt material. The particle size of the carbon nanotubes is 100 nm.
[0025] The preparation method of the asphalt modifier is that 20 g of epoxy soybean oil is added to a closed container, then 3.8 g of methyl tetrahydrophthalic anhydride is added, after uniform stirring, 0.12 g of tetrabutylammonium bromide is added under nitrogen atmosphere while stirring, the stirring speed is 300 rpm, after the addition is completed, the temperature is raised to 85℃, and the stirring is carried out at 500 rpm for 80 min, after the reaction is completed, it is filtered after cooling to obtain the asphalt modifier.
[0026] The preparation method of the composite flame retardant comprises mixing and compounding steps; The mixing step is that 4.1 g of magnesium hydroxide and 6.3 g of ammonium polyphosphate are added to 100 g of anhydrous ethanol, the temperature is raised to 50℃, and stirring is carried out for 30 min, then 1.7 g of bio-based silane coupling agent is added, and the temperature is maintained and stirred for 60 min to obtain the flame retardant; The compounding step is that 70 g of deionized water is added to 6.4 g of graphene, ultrasonic dispersion is carried out, the ultrasonic power is controlled to be 370 W, the ultrasonic frequency is 30 kHz, the ultrasonic time is 30 min, after the ultrasonic is completed, 10.5 g of the flame retardant is added, the temperature is raised to 50℃, and stirring is carried out at 700 rpm for 2.0 h, the temperature is raised to 72℃, then the temperature of the maleic anhydride grafted polyethylene solution is reduced to 72℃, 3.3 g of the maleic anhydride grafted polyethylene solution is added, and stirring is carried out at 250 rpm for 1.2 h to obtain the composite flame retardant; The maleic anhydride grafted polyethylene solution is a mixed solution of maleic anhydride grafted polyethylene and xylene at 115℃, and the mass ratio of the maleic anhydride grafted polyethylene to xylene is 5.5:27.5; The maleic anhydride grafted polyethylene has a melt index of 12 g / 10 min under the condition of 180℃ and 2.16 kg; The preparation method of the bio-based silane coupling agent is that 8.3 g of castor oil acid and 4.0 g of γ-aminopropyl triethoxysilane are added to a closed container, stirring is carried out at 350 rpm for 15 min under nitrogen protection, then 0.15 g of sulfamic acid is added, the temperature is raised to 80℃ at a rate of 2.0℃ / min, and temperature-maintained stirring is carried out for 20 min, then the temperature is raised to 105℃ at a rate of 1.0℃ / min, and temperature-maintained reaction is carried out for 2.0 h, after the reaction is completed, it is filtered, washed and dried to obtain the bio-based silane coupling agent. Example 3
[0027] A preparation method of the flame-retardant modified asphalt waterproof coiled material is that the flame-retardant modified asphalt material is respectively coated on both sides of the base layer to obtain an upper flame-retardant modified asphalt layer and a lower flame-retardant modified asphalt layer, polyethylene films are respectively covered on both sides of the flame-retardant modified asphalt layers to obtain an upper protective layer and a lower protective layer, and the flame-retardant modified asphalt waterproof coiled material is obtained after heat pressing and cooling; The fire-retardant modified asphalt waterproof coiled material has an upper protective layer, an upper fire-retardant modified asphalt layer, a base layer, a lower fire-retardant modified asphalt layer and a lower protective layer from top to bottom. The base layer is a polyester fiber non-woven fabric with a thickness of 0.25 mm. The coating thickness of the fire-retardant modified asphalt material is 1.4 mm. The thickness of the polyethylene film is 0.23 mm.
[0028] The preparation method of the fire-retardant modified asphalt material is as follows: 100 g of 70# asphalt is added to a closed container, the temperature is raised to 167℃, and stirring is carried out at 310 rpm for 32 min, 4.5 g of styrene-butadiene-styrene copolymer is added, the temperature is raised to 180℃, and shearing dispersion is carried out at 2300 rpm for 18 min, 2.2 g of naphthenic oil is added, and shearing dispersion is continued for 27 min, 5.3 g of carbon nanotubes is added, the temperature is reduced to 172℃, stirring is carried out at 1300 rpm for 37 min, then the temperature is reduced to 144℃, 9.2 g of asphalt modifier is added, stirring is carried out at 640 rpm for 38 min, 6.7 g of composite flame retardant is added, and heat preservation stirring is carried out for 32 min, then 2.2 g of naphthenic oil is added, and heat preservation stirring is carried out for 27 min, finally 2.6 g of isophorone diisocyanate is added, and stirring is carried out at 133℃ for 38 min, to obtain the fire-retardant modified asphalt material. The particle size of the carbon nanotubes is 110 nm.
[0029] The preparation method of the asphalt modifier is as follows: 23 g of epoxy soybean oil is added to a closed container, then 4.0 g of methyl tetrahydrophthalic anhydride is added, after uniform stirring, 0.14 g of tetrabutylammonium bromide is added under a nitrogen atmosphere while stirring, the stirring speed is 310 rpm, after the addition is completed, the temperature is raised to 87℃, and stirring is carried out at 510 rpm for 83 min, after the reaction is completed, cooling and filtration are carried out, to obtain the asphalt modifier.
[0030] The preparation method of the composite flame retardant comprises a mixing step and a compounding step. The mixing step is as follows: 4.4 g of magnesium hydroxide and 6.5 g of ammonium polyphosphate are added to 100 g of anhydrous ethanol, the temperature is raised to 52℃, and stirring is carried out for 27 min, then 1.8 g of bio-based silane coupling agent is added, and heat preservation stirring is carried out for 58 min, to obtain the flame retardant. The compounding step is that 74 g of deionized water is added to 6.5 g of graphene, ultrasonic dispersion is performed, the ultrasonic power is controlled to be 380 W, the ultrasonic frequency is 27 kHz, the ultrasonic time is 25 min, after the ultrasonic ends, 10.7 g of the flame retardant is added, the temperature is increased to 52 ℃, stirring is performed at 720 rpm for 1.8 h, the temperature is increased to 75 ℃, then the temperature of the maleic anhydride grafted polyethylene solution is reduced to 75 ℃, 3.4 g of the maleic anhydride grafted polyethylene solution is added, and stirring is performed at 260 rpm for 1.0 h to obtain the compounded flame retardant; The maleic anhydride grafted polyethylene solution is a mixture of maleic anhydride grafted polyethylene and xylene at 117 ℃, and the mass ratio of the maleic anhydride grafted polyethylene to xylene is 5.5:28.5; The maleic anhydride grafted polyethylene has a melt index of 13 g / 10 min under the condition of 180 ℃ and 2.16 kg; The preparation method of the bio-based silane coupling agent is that 8.6 g of ricinoleic acid and 4.2 g of γ-aminopropyl triethoxysilane are added to a closed container, stirring is performed at 370 rpm for 13 min under nitrogen protection, then 0.16 g of sulfamic acid is added, the temperature is increased to 82 ℃ at a rate of 2.2 ℃ / min, and stirring is performed for 25 min, then the temperature is increased to 107 ℃ at a rate of 1.2 ℃ / min, and reaction is performed for 1.7 h, after the reaction ends, filtration, washing and drying are performed to obtain the bio-based silane coupling agent.
[0031] Comparative Example 2-1 On the basis of Example 2, the following changes are made: 1. In the preparation method of the compounded flame retardant, the preparation of the bio-based silane coupling agent is omitted, and the bio-based silane coupling agent is replaced by an equal amount of γ-aminopropyl triethoxysilane; 2. The preparation method of the asphalt modifier is omitted, and the asphalt modifier is replaced by an equal amount of epoxy soybean oil; The remaining operations are exactly the same.
[0032] Comparative Example 2-2 On the basis of Example 2, the following changes are made: 1. In the preparation method of the flame-retardant modified asphalt material, the operation step of “finally, 2.5 g of isophorone diisocyanate is added, and stirring is performed at 132 ℃ for 40 min” is omitted; and the operation step of “then, 2.0 g of naphthenic oil is added, and stirring is performed for 30 min” is omitted, and the first addition amount of naphthenic oil is modified to 4.0 g; 2. In the compounding step of the preparation method of the compounded flame retardant, the operation step of “then, 3.3 g of the maleic anhydride grafted polyethylene solution is added, the temperature is increased to 75 ℃, and stirring is performed at 250 rpm for 1.2 h” is omitted; The remaining operations are exactly the same.
[0033] Test test 1. Waterproof performance The flame-retardant modified asphalt waterproofing membranes prepared from Examples 1-3, Comparative Example 2-1, Comparative Example 2-2 were tested for waterproof performance according to the method in GB / T23457-2009, the pressure of the water-facing surface of the waterproofing membrane was controlled at 0.2 MPa, maintained for 2 h, and every 0.01 MPa was maintained for 30 min until water penetration occurred, and the pressure at the time of water penetration was recorded. The results are as follows:
[0034] 2. Flame-retardant performance The flame-retardant modified asphalt waterproofing membranes prepared from Examples 1-3, Comparative Example 2-1, Comparative Example 2-2 were tested for limiting oxygen index according to the methods in GB18242-2008 “Elastomer modified asphalt waterproofing membrane” and GB / T2408-2021 “Determination of the ignition behavior of plastics - Horizontal and vertical method”. The test results are as follows:
[0035] 3. Physical performance The flame-retardant modified asphalt waterproofing membranes prepared from Examples 1-3, Comparative Example 2-1, Comparative Example 2-2 were tested for tensile properties, tear strength, joint peel strength, heat resistance, and low-temperature flexibility according to GB / T328-2007 “Test methods for building waterproofing materials”. The test results are as follows:
[0036] 4. Aging resistance The flame-retardant modified asphalt waterproofing membranes prepared from Examples 1-3, Comparative Example 2-1, Comparative Example 2-2 were placed in an environment with a temperature of 70°C and a humidity of 65% for 10 days, and then placed in an environment with an ultraviolet radiation intensity of 0.8 W / cm 2 , a temperature of 40°C for 10 days. After the radiation ended, the tensile properties, tear strength, joint peel strength, and low-temperature flexibility were tested according to GB / T328-2007 “Test methods for building waterproofing materials”. The test results are as follows:
[0037] The structure of the fire-retardant modified asphalt waterproof coiled material is five layers, through the synergistic effect between the components, the mechanical properties are ensured while the fire-retardant properties are improved, and the waterproof performance and aging resistance are enhanced, wherein the upper and lower fire-retardant modified asphalt layers are formed by the fire-retardant modified asphalt material, the fire-retardant modified asphalt material is based on 70# asphalt as a matrix, through the addition of styrene-butadiene-styrene copolymer, the rigid structure and flexible structure are introduced, the low-temperature flexibility is ensured while the high-temperature resistance is enhanced, the compatibility of the asphalt modifier and the asphalt system is good, the balance of the flexible chain segment and the rigid chain segment is further optimized, the synergistic composite fire-retardant agent is ensured, the dispersion performance in the asphalt system is ensured, through twice addition of naphthenic oil, the viscosity of the system is effectively adjusted, the isocyanate can be firmly combined with the asphalt, the crosslinking network is constructed, the waterproof performance is enhanced, the fire-retardant properties of the fire-retardant modified asphalt material are improved, and the mechanical properties and high-temperature stability are improved.
[0038] Specifically, the asphalt modifier is combined by epoxy soybean oil and methyl tetrahydrophthalic anhydride under the action of tetrabutylammonium bromide to introduce a flexible long chain to enhance low-temperature flexibility, and the anhydride can improve high-temperature stability as a rigid structure, and the compatibility of the anhydride and the styrene-butadiene-styrene copolymer is good, promoting the formation of an interpenetrating network structure and enhancing aging resistance. Specifically, the composite fire-retardant agent is prepared by compounding magnesium hydroxide and ammonium polyphosphate as a fire-retardant agent, then treated by a bio-based organosilane coupling agent, and then compounded with graphene; in the mixing step, the bio-based silane coupling agent is combined with the fire-retardant agent components, the bio-based silane coupling agent is chemically combined by using amino silane coupling agent and castor oil acid as raw materials under the catalytic action, the obtained bio-based silane coupling agent is used as a bridging agent to enhance the compatibility of magnesium hydroxide, ammonium polyphosphate and the like with asphalt, improve the dispersibility in the asphalt system, and further improve the fire-retardant properties while ensuring the mechanical properties; in the compounding step, the sheet structure of graphene can form a physical barrier layer to better play the fire-retardant properties, the maleic anhydride grafted polyethylene is combined, the maleic anhydride is combined with the hydroxyl group of graphene, the polyethylene chain segment has good compatibility with asphalt, and the dispersibility in the asphalt system is further enhanced, and finally the obtained composite fire-retardant agent forms a multiple fire-retardant system, which can not only enhance the fire-retardant properties, but also improve the mechanical properties and stability.
[0039] The comparative example 2-1 directly uses γ-aminopropyl triethoxysilane as a silane coupling agent to treat magnesium hydroxide and ammonium polyphosphate, and only uses epoxy soybean oil as a bitumen modifier when modifying bitumen. The treatment effect of the silane coupling agent is poor, which leads to poor dispersibility in the bitumen system, and further affects the flame retardancy and mechanical properties, and reduces the aging resistance; the comparative example 2-2 omits the isophorone diisocyanate component in the preparation of the flame-retardant modified bitumen material, and adds naphthenic oil at one time, which cannot fully play the role of viscosity adjustment, leading to uneven dispersibility of the bitumen system, and cannot realize the crosslinking network, reducing the mechanical properties, heat resistance and aging resistance of the waterproof roll material. In the preparation method of the composite flame retardant, the maleic anhydride grafted polyethylene component is omitted, further reducing the overall performance of the waterproof roll material.
[0040] Unless otherwise specified, the proportions described in the present application are mass proportions, and the percentages described are mass percentages.
[0041] Finally, it should be noted that: the above only describes the preferred embodiments of the present application, and is not used to limit the present application, although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.
Claims
1. A method for preparing a flame-retardant modified asphalt waterproofing membrane, characterized in that, The flame-retardant modified asphalt material is coated on both sides of the tire base layer to obtain an upper flame-retardant modified asphalt layer and a lower flame-retardant modified asphalt layer. The preparation method of the flame-retardant modified asphalt material comprises the following steps: adding 70# asphalt, styrene-butadiene-styrene copolymer, naphthenic oil, carbon nanotubes, an asphalt modifier, and a composite flame retardant into a closed container in sequence, stirring, then adding naphthenic oil and isophorone diisocyanate to obtain the flame-retardant modified asphalt material; The preparation method of the asphalt modifier comprises the following steps: adding methyl tetrahydrophthalic anhydride into epoxy soybean oil, adding tetrabutylammonium bromide under a nitrogen atmosphere, and stirring at 82-87 ℃ and 460-510 rpm for 78-83 min to obtain the asphalt modifier; The preparation method of the composite flame retardant comprises mixing and compounding steps. The mixing step comprises the following steps: adding magnesium hydroxide and ammonium polyphosphate into anhydrous ethanol, heating to 48-52 ℃, and adding a bio-based silane coupling agent to obtain the flame retardant. The preparation method of the bio-based silane coupling agent comprises the following steps: mixing castor oil acid and γ-aminopropyl triethoxysilane, adding sulfamic acid under nitrogen protection, and stirring at 78-82 ℃ for 18-25 min and at 102-107 ℃ for 1.7-2.2 h to obtain the bio-based silane coupling agent. The compounding step comprises the following steps: adding deionized water to graphene, performing ultrasonic dispersion, adding the flame retardant, stirring at 48-52 ℃ and 670-720 rpm for 1.8-2.2 h, heating to 70-75 ℃, adding a maleic anhydride grafted polyethylene solution, and stirring at 240-260 rpm for 1.0-1.3 h to obtain the composite flame retardant.
2. The preparation method of the flame-retardant modified asphalt waterproof coiled material according to claim 1, characterized in that, The preparation method of the flame-retardant modified asphalt material comprises the following steps: adding 70# asphalt into a closed container, heating to 162-167 ℃, and stirring at 280-310 rpm for 27-32 min, adding styrene-butadiene-styrene copolymer, heating to 175-180 ℃, and shearing and dispersing at 2000-2300 rpm for 18-22 min, adding naphthenic oil for the first time, continuing shearing and dispersing for 23-27 min, adding carbon nanotubes, reducing the temperature to 168-172 ℃, and stirring at 1100-1300 rpm for 37-45 min, then reducing the temperature to 140-144 ℃, adding the asphalt modifier, stirring at 610-640 rpm for 38-45 min, adding the composite flame retardant, and heat-stirring for 32-40 min, adding naphthenic oil for the second time, heat-stirring for 27-32 min, finally adding isophorone diisocyanate, and stirring at 128-133 ℃ for 38-43 min to obtain the flame-retardant modified asphalt material; The particle size of the carbon nanotubes is 80-110 nm. The mass ratio of the 70# asphalt, styrene-butadiene-styrene copolymer, naphthenic oil first added, carbon nanotube, asphalt modifier, composite flame retardant, naphthenic oil second added, isophorone diisocyanate is 100:4.0-4.5:1.8-2.2:4.8-5.3:8.7-9.2:6.2-6.7:1.8-2.2:2.4-2.
6.
3. The preparation method of the flame-retardant modified asphalt waterproof coiled material according to claim 1, characterized in that, In the preparation method of the asphalt modifier, the mass ratio of the epoxy soybean oil, methyl tetrahydrophthalic anhydride and tetrabutylammonium bromide is 18-23:3.7-4.0:0.10-0.
14.
4. The preparation method of the flame-retardant modified asphalt waterproof coiled material according to claim 1, characterized in that, In the mixing step, the mass ratio of the magnesium hydroxide, sodium polyphosphate, anhydrous ethanol and bio-based silane coupling agent is 4.0-4.4:6.0-6.5:100:1.5-1.
8.
5. The preparation method of the flame-retardant modified asphalt waterproof coiled material according to claim 1, characterized in that, In the compounding step, the ultrasonic dispersion has an ultrasonic power of 360-380 W, an ultrasonic frequency of 27-32 kHz and an ultrasonic time of 25-35 min; The mass ratio of the graphene, deionized water, flame retardant and maleic anhydride grafted polyethylene solution is 6.2-6.5:68-75:10.2-10.7:3.0-3.4; The maleic anhydride grafted polyethylene solution is a mixture of maleic anhydride grafted polyethylene and xylene at 112-117℃, and the mass ratio of the maleic anhydride grafted polyethylene and xylene is 5.5:24.5-28.5; The maleic anhydride grafted polyethylene has a melt index of 10-13 g / 10 min at 180℃ and under a load of 2.16 kg.
6. The preparation method of the flame-retardant modified asphalt waterproof coiled material according to claim 1, characterized in that, In the preparation method of the bio-based silane coupling agent, the mass ratio of the ricinoleic acid, γ-aminopropyl triethoxysilane and sulfamic acid is 8.2-8.6:3.8-4.2:0.13-0.
16.
7. The preparation method of the flame-retardant modified asphalt waterproof coiled material according to claim 1, characterized in that, The preparation method of the flame-retardant modified asphalt waterproof coiled material is to coat the flame-retardant modified asphalt material on both sides of the base layer respectively to obtain an upper flame-retardant modified asphalt layer and a lower flame-retardant modified asphalt layer, cover polyethylene films on both sides of the flame-retardant modified asphalt layer respectively to obtain an upper protective layer and a lower protective layer, and obtain the flame-retardant modified asphalt waterproof coiled material through hot pressing and cooling; The flame-retardant modified asphalt waterproof coiled material has an upper protective layer, an upper flame-retardant modified asphalt layer, a base layer, a lower flame-retardant modified asphalt layer and a lower protective layer from top to bottom; The base layer is a polyester fiber non-woven fabric with a thickness of 0.20-0.25 mm; The coating thickness of the flame-retardant modified asphalt material is 1.2-1.4 mm; The polyethylene film has a thickness of 0.18-0.23 mm.
8. The flame-retardant modified asphalt waterproofing membrane prepared by the method according to any one of claims 1-7.