Modified asphalt waterproofing membrane and method for preparing the same
By introducing organic ammonium salt-modified layered silicates, surface-treated magnesium hydroxide with silane, and composite metal oxide fillers into modified bitumen waterproof membranes, a multiphase synergistic structure is constructed, which solves the problem of insufficient durability of existing modified bitumen waterproof membranes in salt spray and chemical media environments, and achieves long-term stability and waterproof performance in harsh environments.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- QINGDAO ORIENTAL YUHONG BUILDING MATERIALS CO LTD
- Filing Date
- 2026-04-14
- Publication Date
- 2026-06-30
AI Technical Summary
Existing SBS modified bitumen waterproof membranes lack durability in salt spray and chemical media environments, are prone to performance degradation, lack effective barrier against chloride ions, acid and alkali media, and inhibit chemical media migration. The elastomeric modified system also lacks stability in chemical media environments.
A functional filler system is adopted, including organic ammonium salt modified layered silicate, surface silane treated magnesium hydroxide and composite metal oxide filler, to form a multiphase synergistic structure. Through ion adsorption, passivation and barrier mechanisms, the stability of the asphalt resin phase and the interfacial bonding performance are enhanced. Combined with polar modified components and stabilizing additives, a multi-protection mechanism is constructed.
It significantly improves the waterproof and mechanical properties of modified bitumen waterproof membranes in salt spray and chemical media environments, extends service life, effectively inhibits the penetration of corrosive media, and maintains the long-term stability of the material.
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Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of asphalt waterproof membranes, and relates to a modified asphalt waterproof membrane and its preparation method. Background Technology
[0002] In coastal areas, saline-alkali regions, and engineering environments such as chemical plants, sewage treatment plants, and underground utility tunnels, waterproof membranes are frequently exposed to salt spray, high humidity, and chemical media such as acids, alkalis, and salts, which can easily lead to performance degradation. Corrosive media such as chloride and sulfate ions can penetrate the asphalt system, causing an imbalance in the ratio of asphalt binder to asphaltenes, resulting in material softening, embrittlement, or bonding failure. Existing SBS modified bitumen waterproof membranes are mainly designed for temperature adaptability, lacking specific formulation control for salt spray and chemical resistance, resulting in a significantly shortened service life in these harsh environments.
[0003] Existing asphalt waterproof membranes have the following defects: (1) The asphalt matrix has limited barrier ability against chloride ions and acid and alkali media, and is prone to penetration and erosion; (2) Conventional fillers are mostly inert fillers, which are difficult to suppress the migration of chemical media; (3) The elastomer-modified system is not stable enough in a chemical medium environment and is prone to aging and failure; (4) Lack of synergistic protection mechanisms under the dual effects of salt spray and chemical media. Summary of the Invention
[0004] In view of this, the present invention provides a modified bitumen waterproof membrane and its preparation method, aiming to construct a modified bitumen system with multiple protection mechanisms of "barrier-passivation-stabilization-synergy", so that the waterproof membrane can maintain long-term stable waterproof and mechanical properties in salt spray and chemical media environments.
[0005] To achieve the above objectives, the present invention adopts the following technical solution.
[0006] In a first aspect, the present invention provides a modified bitumen waterproof membrane, comprising a base layer and a modified bitumen layer, wherein the modified bitumen layer comprises the following components: Base bitumen: 40-55 parts; Elastomer: 6-10 parts; Polar modification component: 2-6 parts; Functional filler: 5-10 parts; Stabilizing agent: 0.5~1.5 parts; wherein, The elastomer includes at least one of SBS and SEBS; The polar modification component includes at least one of maleic anhydride-grafted polyolefin resin and polar rubber. The functional filler includes or is selected from one or more of the following: organoammonium salt modified layered silicates, surface-treated magnesium hydroxide, and composite metal oxide fillers; The stabilizing agent includes at least one of antioxidants and chemical stabilizers.
[0007] The modified bitumen waterproof membrane provided by this invention comprises a functional filler forming an "adsorption-barrier" dual pathway in the bitumen system, reducing the effective diffusion of corrosive media; a polar modified component enhancing the bitumen resin phase, improving the system's resistance to chemical media; an elastomer maintaining structural integrity in corrosive environments, preventing the propagation of microcracks; and a multiphase synergistic structure in the modified bitumen waterproof membrane complicates the erosion path, prolonging the media penetration time.
[0008] Optionally, the base asphalt is at least one of 70# petroleum asphalt and 90# petroleum asphalt.
[0009] Preferably, the maleic anhydride-grafted polyolefin resin in the polar modification component includes one or a combination of several of maleic anhydride-grafted polyethylene (PE-g-MAH) resin, maleic anhydride-grafted polypropylene (PP-g-MAH) resin, maleic anhydride-grafted SEBS (SEBS-g-MAH) resin, and maleic anhydride-grafted EVA (EVA-g-MAH) resin.
[0010] More preferably, the maleic anhydride-grafted polyolefin resin includes at least one of maleic anhydride-grafted SEBS resin and maleic anhydride-grafted polypropylene resin.
[0011] More preferably, the grafting rate of maleic anhydride in the maleic anhydride-grafted polyolefin resin is 0.5% to 2.0% (e.g., 0.8%, 1.0%, 1.5% or 1.8%).
[0012] Preferably, the polar rubber is a rubber material containing polar functional groups, including one or a combination of several of nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), chloroprene rubber (CR), carboxylated nitrile rubber (XNBR), and acrylate rubber (ACM).
[0013] More preferably, the polar rubber is at least one of nitrile butadiene rubber (NBR) and hydrogenated nitrile butadiene rubber (HNBR).
[0014] Optionally, in the organic ammonium salt modified layered silicate, the layered silicate includes montmorillonite, and the montmorillonite includes sodium-based montmorillonite (e.g., natural sodium-based montmorillonite).
[0015] In this invention, the organoammonium salt modified layered silicate is essentially similar to organomontmorillonite or organobentonite, and has the following mechanism of action: (1) Ion exchange / ion adsorption in layered structures, for example, layered silicate crystal layers carry a negative charge, and cations can be exchanged between the layers, which is beneficial for Cl. - SO4 2- Corrosion ions have adsorption and retention effects; (2) Constructing a “tortuous diffusion path”: Because the nanosheets are dispersed in the asphalt, the diffusion path of the corrosive medium is lengthened, thereby improving the barrier to the corrosive medium.
[0016] Preferably, in the organic ammonium salt modified layered silicate, the organic ammonium salt is selected from quaternary ammonium salts, and more preferably long-chain alkyl quaternary ammonium salts.
[0017] More preferably, the quaternary ammonium salt includes or is selected from at least one of hexadecyltrimethylammonium bromide (CTAB), octadecyltrimethylammonium chloride (OTAC), dioctadecyldimethylammonium chloride (DODAC), dimethyldistearate ammonium chloride, and octadecyldimethylbenzylammonium chloride.
[0018] More preferably, the quaternary ammonium salt is at least one of hexadecyltrimethylammonium bromide (CTAB) and dioctadecyldimethylammonium chloride.
[0019] In this invention, the organic ammonium salt modified layered silicate is preferably a long-chain alkyl quaternary ammonium salt because long-chain alkyl groups can increase the interlayer spacing of the modified layered silicate and improve organic compatibility.
[0020] Optionally, the interlayer spacing of the organoammonium salt modified layered silicate is ≥1.8 nm, and the specific surface area is ≥200 m². 2 / g.
[0021] Optionally, the surface-treated magnesium hydroxide has an average particle size of 1-3 μm and a pH value of 9.5-10.5 (e.g., 10).
[0022] In this invention, the surface-treated magnesium hydroxide with silane mainly serves as a barrier and protective agent, as detailed below: (1) Neutralization effect: Mg(OH)2 can neutralize acidic corrosive media and provide an alkaline environment; (2) Barrier filler function: Magnesium hydroxide is filled into the modified bitumen waterproof membrane in the form of particles to improve the density of the material; (3) Improve resistance to chemical corrosion; (4) Magnesium hydroxide is surface-treated with silane to improve its compatibility with asphalt, prevent filler agglomeration, and improve interfacial bonding ability.
[0023] Optionally, the composite metal oxide filler includes at least one of the ZnO–Al2O3 system and the MgO–Al2O3 system, used to adsorb and passivate corrosive ions.
[0024] In this invention, the composite metal oxide filler is added to the modified bitumen waterproof membrane to slowly release Zn metal ions. 2+ Al 3+ Mg 2+ These ions can react with corrosive media to form stable salts, thereby slowing down the corrosion process. In addition, composite metal oxide fillers passivate the material surface, forming a protective deposition layer, such as Zn(OH)2 and Al(OH)3, to prevent the material surface from being corroded.
[0025] In this invention, the functional filler comprises or is selected from one or a combination of the following: ① Organic ammonium salt modified layered silicates with interlayer spacing ≥ 1.8 nm and specific surface area ≥ 200 m² 2 / g; ② Surface-treated magnesium hydroxide with silane, average particle size 1~3 μm, pH value 9.5~10.5; ③ Composite metal oxide fillers (ZnO–Al2O3 or MgO–Al2O3 system) are used to adsorb and passivate corrosive ions. The functional fillers are chemically resistant inorganic fillers and have the following functions: (1) Formation of nano barrier structure: After the layered silicate is modified by organic ammonium salt, the interlayer spacing increases, which can form a peeling or intercalation structure in the asphalt system, thereby constructing a nanoscale sheet barrier network; this nano barrier structure can prolong the chloride ion diffusion path and reduce the medium permeation rate; (2) Improve the stability of asphalt phase: Layered silicates have a high specific surface area, which can adsorb the gum and aromatics in asphalt, thereby stabilizing the asphalt colloidal structure; (3) Enhanced interfacial bonding: After organic modification, the surface of layered silicates exhibits organic affinity, making them more uniformly dispersed in asphalt and improving the overall stability of the material.
[0026] Optionally, the antioxidant includes or is selected from at least one of hindered phenolic antioxidants 1010 and 1076.
[0027] Optionally, the chemical stabilizer includes or is selected from at least one of metal passivators and phosphate ester stabilizers, for inhibiting chemically induced oxidative degradation.
[0028] Preferably, the phosphate ester stabilizer comprises or is selected from one or more of the following compounds: Triphenyl phosphate (TPP), Tricresyl phosphate (TCP), Trinonylphenyl phosphate (TNPP), Tripropylphenyl phosphate, Bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphate, Tri(2,4-di-tert-butylphenyl) phosphite, and Trinonylphenyl phosphite.
[0029] More preferably, the phosphate ester stabilizer includes one or a combination of two of trinonylphenyl phosphate (TNPP) and bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphate to obtain better processing stability and long-term antioxidant properties.
[0030] Optionally, the preparation method of the organoammonium salt modified layered silicate includes the following steps: Step 1: Disperse the layered silicate in deionized water to prepare a suspension with a mass fraction of 3-5 wt% (e.g., 3.5 wt%, 4 wt%, or 4.5 wt%). Step 2: Heat the suspension to 70-80°C and stir to allow the layered silicates to fully expand; Step 3: Add an organic ammonium salt solution to the heated suspension and react at 70℃~80℃ for 2~4 h to carry out cation exchange; Step 4: Filter and wash the reaction system after cation exchange (until no Cl is visible). - After drying and pulverizing, organic ammonium salt modified layered silicate powder is obtained.
[0031] Preferably, in step 3, the mass of the organic ammonium salt in the organic ammonium salt solution is 1.0 to 1.5 times (e.g., 1.2 times or 1.4 times) the cation exchange capacity (CEC) of the layered silicate.
[0032] Preferably, in step 4, the drying temperature is 70~85℃ (e.g., 75℃ or 80℃) and the time is 10~15 h (e.g., 12 h).
[0033] In this invention, the effect of surface silane treatment on magnesium hydroxide is as follows: (1) Neutralize acidic media; Magnesium hydroxide has weak alkalinity and can neutralize acidic corrosive media, for example, H2SO4 + Mg(OH)2 → MgSO4 + 2H2O, thereby reducing acid corrosion; (2) Improve interfacial compatibility; Surface-treated magnesium hydroxide obtained by treating magnesium hydroxide with silane coupling agent can improve the compatibility between inorganic fillers and asphalt and reduce interfacial defects; (3) Improve the aging resistance of materials; magnesium hydroxide can absorb heat and release moisture during thermal decomposition, for example, Mg(OH)2→ MgO + H2O, thereby delaying thermal oxidative aging.
[0034] Preferably, the surface-treated magnesium hydroxide is prepared by using a silane coupling agent to treat magnesium hydroxide powder; the silane coupling agent is one or more of aminosilane, epoxysilane, or methacryloxysilane.
[0035] More preferably, the silane coupling agent includes at least one of γ-aminopropyltriethoxysilane (KH-550), γ-glycidoxypropyltrimethoxysilane (KH-560), and γ-methacryloyloxypropyltrimethoxysilane (KH-570).
[0036] More preferably, the mass of the silane coupling agent is 0.5 to 2 wt% (e.g., 1 wt% or 1.5 wt%) of the mass of magnesium hydroxide.
[0037] More preferably, the method for preparing the surface-silane-treated magnesium hydroxide includes the following steps: Step 1, Hydrolysis of coupling agent: The silane coupling agent was added to an ethanol / water mixed solution, and glacial acetic acid was added under stirring to adjust the pH of the system to 4-5, so that the silane coupling agent would undergo a hydrolysis reaction to obtain a hydrolyzed silane solution. Step 2, Surface modification treatment of magnesium hydroxide: Under heating and stirring, the hydrolyzed silane solution from step 1 is sprayed onto the surface of magnesium hydroxide powder to cause the silane coupling agent to undergo a condensation reaction with the hydroxyl groups on the surface of magnesium hydroxide. Then, the powder is dried, pulverized, and sieved to obtain surface silane-treated magnesium hydroxide powder.
[0038] Preferably, in the method for preparing surface-treated magnesium hydroxide with silane, in step 1, the volume ratio of ethanol to water in the ethanol / water mixed solution is 3:1 to 5:1 (e.g., 3.5:1, 4:1 or 4.5:1), and the hydrolysis reaction time is 20 to 40 min. Preferably, in the method for preparing surface-treated magnesium hydroxide with silane, in step 2, the heating and stirring temperature is 60-80°C (e.g., 70°C), and the heating and stirring reaction time is 30-60 min.
[0039] Preferably, in the method for preparing surface-treated magnesium hydroxide, step 2, the heating and stirring are carried out in a high-speed stirring reactor or a high-speed mixer.
[0040] Preferably, in the method for preparing surface-treated magnesium hydroxide with silane, in step 2, the drying temperature is 90-110°C (e.g., 95°C, 100°C, or 105°C) and the time is 2-4 h to remove solvent and unreacted substances.
[0041] Preferably, in step 2, the average particle size of the magnesium hydroxide powder is 0.8–3 μm.
[0042] In this invention, magnesium hydroxide powder is added to a high-speed stirred reactor or a high-speed mixer and stirred and dispersed at 60-80°C. Then, the above-mentioned hydrolyzed silane solution is slowly sprayed in to uniformly coat the surface of the magnesium hydroxide particles. The reaction is continued for 30-60 minutes to allow the silane coupling agent to undergo a condensation reaction with the hydroxyl groups on the surface of the magnesium hydroxide.
[0043] Preferably, in the preparation method of the surface silane-treated magnesium hydroxide, in step 2, the dried material is pulverized by air jet milling or mechanical milling and then passed through a 325-mesh sieve to obtain surface silane-treated magnesium hydroxide powder.
[0044] In this invention, an organosilane modified layer is formed on the surface of magnesium hydroxide particles after surface silane treatment, which can significantly improve the interfacial compatibility and dispersion stability between the particles and the asphalt matrix and polymer modifier, thereby improving the salt spray resistance, chemical corrosion resistance and long-term stability of the waterproof membrane.
[0045] Secondly, the present invention provides a method for preparing a modified bitumen waterproof membrane, comprising the following steps: Step 1: Heat the base asphalt to melt, add the elastomer and shear mix to form a modified asphalt matrix; Step 2: Add polar modifying components to the modified asphalt matrix and continue shearing and mixing; then cool down and add functional fillers and stabilizing agents for mixing to obtain modified asphalt; Step 3: Combine the modified bitumen with the base material, cool and mold to obtain the modified bitumen waterproof membrane.
[0046] Optionally, in step 1, the temperature at which the material is heated to the melting point is 160~170°C (e.g., 165°C).
[0047] Optionally, in step 1, the shearing temperature of the shear mixing is 165~180℃ (e.g., 170℃ or 175℃), and the shearing speed is 1200~1800 rpm (e.g., 1400 rpm, 1500 rpm or 1600 rpm).
[0048] Optionally, in step 1, the shearing time for shear mixing is 10-15 min (e.g., 12 min).
[0049] Optionally, in step 2, the shearing time for shear mixing is 10-15 min (e.g., 12 min).
[0050] Optionally, in step 2, the functional filler and stabilizing agent are added and mixed after the temperature is lowered by 145~155℃ (e.g., 150℃); the mixing speed is lower than the shear speed in step 1.
[0051] Optionally, in step 3, the modified bitumen is combined with the base material by dip coating or calendering, and then cooled and molded to obtain a modified bitumen waterproof membrane.
[0052] Optionally, in step 3, the thickness of the modified bitumen waterproof membrane is 3.0~4.0 mm, wherein the thickness of the base material is 0.8~1.2 mm (e.g., 1 mm), and the thickness of the coating on both sides of the base material is 1.0-2.0 mm.
[0053] In this invention, the above-mentioned technical features can be freely combined to form new technical solutions, provided they do not conflict with each other.
[0054] Compared with the prior art, the technical solution provided by the present invention has the following beneficial technical effects: (1) The modified bitumen waterproof membrane provided by the present invention adopts a chemical erosion resistant functional filler system. By introducing functional fillers with ion adsorption and / or slow release passivation capabilities, the migration rate of chloride ions and acid and alkali media in bitumen is reduced. (2) The modified bitumen waterproof membrane provided by the present invention adopts a polar-enhanced modified bitumen matrix. The polar modified components regulate the asphalt colloidal structure and improve the stability of asphalt relative to chemical media. In addition, the polar modified components combine with the organic ammonium salt modified layered silicate in the functional filler to form an interfacial synergistic effect: the polar functional groups can generate hydrogen bonding and polar interaction with the surface of layered silicate, thereby improving the dispersibility of the filler, improving the interfacial bonding performance, and improving the chemical erosion resistance. (3) The modified bitumen waterproof membrane provided by the present invention adopts an elastomer-stabilizer synergistic anti-erosion mechanism. The elastomer modification and the anti-chemical aging additive work together to slow down the structural deterioration caused by chemical media. (4) The modified bitumen waterproof membrane provided by the present invention adopts a multi-phase barrier synergistic structure design, which forms a multi-scale barrier network with functional fillers, elastomers and bitumen matrix to synergistically improve the ability to resist salt spray and chemical media. (5) The modified bitumen waterproof membrane provided by the present invention effectively inhibits the penetration of corrosive media through a multi-phase synergistic barrier mechanism. Its formulation design takes into account both chemical resistance and mechanical properties without sacrificing construction adaptability. The modified bitumen waterproof membrane has a multi-protection mechanism of "barrier-passivation-stabilization-synergy". It has a high performance retention rate in salt spray and acid and alkali environments, and significantly extends its service life. It is suitable for harsh service environments such as coastal areas, chemical plants and underground engineering. Detailed Implementation
[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0056] Unless otherwise specified, the terminology used herein should be understood as having the meaning commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In the event of any conflict, this specification shall prevail.
[0057] Some specific embodiments of the present invention provide a modified bitumen waterproof membrane, comprising the following components: Base bitumen: 40 to 55 parts (e.g., 42, 45, 48, 50, or 53 parts); Elastomer: 6 to 10 parts (e.g., 7, 8 or 9 parts); Polar modification component: 2 to 6 parts (e.g., 3 parts, 3.5 parts, 4 parts, 4.5 parts or 5 parts); Functional filler: 5 to 10 parts (e.g., 6, 7, 8, 8.5 or 9 parts); Stabilizing agent: 0.5 to 1.5 parts (e.g., 0.6 parts, 0.8 parts, 1.0 parts, 1.2 parts or 1.4 parts); The elastomer includes at least one of SBS and SEBS; The polar modification component includes at least one of maleic anhydride-grafted polyolefin resin and polar rubber. The functional filler includes or is selected from one or more of the following: organoammonium salt modified layered silicates, surface-treated magnesium hydroxide, and composite metal oxide fillers; The stabilizing agent includes at least one of antioxidants and chemical stabilizers.
[0058] In some embodiments of the present invention, the functional filler comprises or is selected from one or more of the following: ① Organic ammonium salt modified layered silicates with interlayer spacing ≥ 1.8 nm and specific surface area ≥ 200 m² 2 / g; ② Surface-treated magnesium hydroxide with silane, average particle size 1~3 μm, pH value 9.5~10.5; ③ Composite metal oxide fillers (ZnO–Al2O3 or MgO–Al2O3 system) are used to adsorb and passivate corrosive ions.
[0059] In some embodiments of the present invention, the chemical stabilizer includes or is selected from metal passivators or phosphate ester stabilizers, for inhibiting chemically induced oxidative degradation.
[0060] In the following embodiments, the 70# / 90# petroleum asphalt is from Shandong Jingbo Petrochemical; the number-average molecular weight (Mn) of the SBS elastomer is 8×10 4 ~12×10 4 Weight-average molecular weight (Mw): 1.5 × 10⁻⁶ 5 ~2.5×10 5 Styrene content: 28–32 wt%; Number average molecular weight (Mn) of SEBS elastomer: 9 × 10⁻⁶ 4 ~13×10 4 Weight-average molecular weight (Mw): 1.8 × 10⁻⁶ 5 ~3.0×10 5 Styrene content: 30-35 wt%; maleic anhydride grafted resin type is PE-g-MAH, brand name is MaterChemM167; hydrogenated nitrile butadiene rubber (HNBR) brand name is Zetpol HNBR-2345; stabilizing agents include antioxidant 1010 (manufactured by BASF) and antioxidant 168 (manufactured by BASF), which are compounded in a 1:1 ratio.
[0061] The modified layered silicates have an interlayer spacing (d001) of 2.2–3.5 nm and a specific surface area of 220–350 m². 2 / g, its preparation method is as follows: Natural sodium-based montmorillonite was dispersed in deionized water to prepare a 4 wt% suspension. The suspension was heated to 70°C and stirred to allow the layered silicates to fully expand. Then, an organic ammonium salt solution (1.25 times the cation exchange capacity (CEC) of montmorillonite) was added, and the reaction was maintained at 70°C for 3 h to carry out cation exchange. The mixture was then filtered and washed until Cl-free. - The solid product was dried at 80℃ for 12 h and then pulverized to obtain organic ammonium salt modified montmorillonite powder.
[0062] Surface-treated magnesium hydroxide is prepared using the following method: Step 1: Select magnesium hydroxide powder with an average particle size of 0.8–3 μm as the matrix material; select γ-aminopropyltriethoxysilane (KH-550) as the silane coupling agent. Step 2, Coupling agent hydrolysis: The silane coupling agent was added to an ethanol / water mixed solution at 1 wt% of magnesium hydroxide mass, wherein the volume ratio of ethanol to water was 4:1. A small amount of glacial acetic acid was added under stirring to adjust the pH to 4.5, so that the silane coupling agent could undergo a hydrolysis reaction. The hydrolysis time was 30 min, and a hydrolyzed silane solution was obtained. Step 3, Surface modification treatment: Magnesium hydroxide powder is added to a high-speed stirred reactor or high-speed mixer and dispersed under stirring at 60-80°C. Then, the above-mentioned hydrolyzed silane solution is slowly sprayed in to uniformly coat the surface of the magnesium hydroxide particles. The reaction is continued for 45 minutes to allow the silane coupling agent to undergo a condensation reaction with the hydroxyl groups on the surface of magnesium hydroxide. After the reaction is completed, the material is placed in a 100°C oven and dried for 3 hours to remove the solvent and unreacted substances. The dried material is then mechanically pulverized and passed through a 325-mesh sieve to obtain surface-treated magnesium hydroxide powder.
[0063] Example 1 A modified bitumen waterproof membrane comprises the following components by weight: Base asphalt: 50 parts, using 70# / 90# petroleum asphalt; SBS elastomer: 8 parts Maleic anhydride grafted resin: 4 parts Modified layered silicate: 8 parts, and Stabilizing agent: 1 part.
[0064] Example 2 A modified bitumen waterproof membrane comprises the following components by weight: Base asphalt: 45 parts, using 70# / 90# petroleum asphalt from Example 1; SEBS elastomer: 10 parts Hydrogenated nitrile butadiene rubber (HNBR, i.e., polar rubber): 3 parts, Surface treatment with magnesium hydroxide: 10 parts Stabilizing agent: 1.2 parts.
[0065] Example 3 A modified bitumen waterproof membrane comprises the following components by weight: Base asphalt: 55 parts, using 70# / 90# petroleum asphalt from Example 1; SBS elastomer: 6 parts Maleic anhydride grafted resin: 2 parts Composite metal oxide: 6 parts, wherein the composite metal oxide adopts the ZnO–Al2O3 system, and ZnO and Al2O3 are mixed in a mass ratio of approximately 2:1; Stabilizing agent: 0.8 parts.
[0066] Example 4 A modified bitumen waterproof membrane comprises the following components by weight: Base asphalt: 50 parts, using 70# / 90# petroleum asphalt from Example 1; SBS elastomer: 8 parts Maleic anhydride grafted resin: 4 parts Functional filler: 8 parts, including 4 parts modified layered silicate, 2 parts surface-treated magnesium hydroxide, 2 parts composite metal oxide, and... Stabilizing agent: 1 part.
[0067] Example 5 A modified bitumen waterproof membrane comprises the following components by weight: Base asphalt: 50 parts, using 70# / 90# petroleum asphalt from Example 1; SBS elastomer: 6 parts Maleic anhydride grafted resin: 2 parts Functional filler (modified layered silicate) 8 parts, and Stabilizing agent: 1 part.
[0068] Comparative Example 1 A modified bitumen waterproof membrane differs from Example 1 in that it does not contain functional fillers (i.e., modified layered silicates), but is otherwise identical to Example 1. Specifically, it comprises the following components by weight: Base asphalt: 50 parts, using 70# / 90# petroleum asphalt; SBS elastomer: 8 parts Maleic anhydride grafted resin: 4 parts, and Stabilizing agent: 1 part.
[0069] Comparative Example 2 A modified bitumen waterproof membrane differs from Example 1 in that it does not contain a polar modifying component (i.e., maleic anhydride grafted resin), but is otherwise identical to Example 1. Specifically, it comprises the following components by weight: A modified bitumen waterproof membrane comprises the following components by weight: Base asphalt: 50 parts, using 70# / 90# petroleum asphalt; SBS elastomer: 8 parts Modified layered silicate: 8 parts, and Stabilizing agent: 1 part.
[0070] Comparative Example 3 A modified bitumen waterproof membrane differs from Example 1 in that it uses ordinary calcium carbonate instead of functional filler to modify layered silicate; otherwise, it is the same as Example 1. Specifically, it comprises the following components by weight: Base asphalt: 50 parts, using 70# petroleum asphalt; SBS elastomer: 8 parts Maleic anhydride grafted resin: 4 parts Ordinary calcium carbonate: 8 parts, and Stabilizing agent: 1 part.
[0071] Performance of modified bitumen waterproof membrane The performance of the modified bitumen waterproof membranes in Examples 1-5 and Comparative Examples 1-3 was tested, as detailed below.
[0072] Salt spray aging test method: The test was conducted in accordance with GB / T 1771-2007 "Determination of resistance to neutral salt spray of paints and varnishes". The sample was placed in a 5% (mass fraction) NaCl solution salt spray environment at a temperature of 35±2℃ and sprayed continuously for 240 h. The change in tensile strength before and after aging was tested.
[0073] Acid and alkali immersion test method: The cut waterproof membrane samples were immersed in 5% sulfuric acid solution (pH≈1) and 5% sodium hydroxide solution (pH≈13) respectively. The immersion temperature was 25±2℃ and the immersion time was 168 h. After removal, the samples were rinsed with deionized water and air-dried for 24 h. The change in elongation before and after immersion was tested according to GB / T 328.8-2007, and the elongation retention rate was calculated.
[0074] Water absorption rate: Tested according to GB / T 328.27.
[0075] Low-temperature gentleness: Tested according to GB / T 328.14.
[0076] Table 1 lists the relevant properties of modified bitumen waterproof membranes.
[0077] Table 1 Performance of Modified Bituminous Waterproof Membrane
[0078] The above descriptions are merely some preferred embodiments of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.
Claims
1. A modified bitumen waterproof membrane, characterized in that, It includes a base course and a modified asphalt layer, wherein the modified asphalt layer comprises the following components: Base bitumen: 40-55 parts; Elastomer: 6-10 parts; Polar modification component: 2-6 parts; Functional filler: 5-10 parts; Stabilizing agent: 0.5~1.5 parts; The elastomer includes at least one of SBS and SEBS; The polar modification component includes at least one of maleic anhydride-grafted polyolefin resin and polar rubber. The functional filler includes or is selected from one or more of the following: organoammonium salt modified layered silicates, surface-treated magnesium hydroxide, and composite metal oxide fillers; The stabilizing agent includes at least one of antioxidants and chemical stabilizers.
2. The modified bitumen waterproof membrane according to claim 1, characterized in that, The base asphalt is at least one of 70# petroleum asphalt and 90# petroleum asphalt; In the polar modified component, the maleic anhydride-grafted polyolefin resin includes one or a combination of maleic anhydride-grafted polyethylene resin, maleic anhydride-grafted polypropylene resin, maleic anhydride-grafted SEBS resin, and maleic anhydride-grafted EVA resin, wherein the grafting rate of maleic anhydride in the maleic anhydride-grafted polyolefin resin is 0.5% to 2.0%; the polar rubber is a rubber material containing polar functional groups, including one or a combination of nitrile rubber, hydrogenated nitrile rubber, chloroprene rubber, carboxylated nitrile rubber, and acrylate rubber. In the organic ammonium salt modified layered silicate, the layered silicate includes montmorillonite, the montmorillonite includes sodium montmorillonite, and the organic ammonium salt is selected from quaternary ammonium salts, the quaternary ammonium salt includes or is selected from at least one of hexadecyltrimethylammonium bromide, octadecyltrimethylammonium chloride, dioctadecyldimethylammonium chloride, dimethyldistearate ammonium chloride, and octadecyldimethylbenzylammonium chloride. The surface-treated magnesium hydroxide is prepared by using a silane coupling agent to react with magnesium hydroxide powder; the silane coupling agent is one or more of aminosilanes, epoxysilanes, or methacryloxysilanes; the mass of the silane coupling agent is 0.5–2 wt% of the mass of magnesium hydroxide. The antioxidant includes or is selected from at least one of hindered phenolic antioxidants 1010 and 1076; The chemical stabilizer includes or is selected from at least one of metal passivators and phosphate ester stabilizers.
3. The modified bitumen waterproof membrane according to claim 1, characterized in that, The interlayer spacing of the organoammonium salt-modified layered silicate is ≥1.8 nm, and the specific surface area is ≥200 m². 2 / g; The surface-treated magnesium hydroxide has an average particle size of 1-3 μm and a pH value of 9.5-10.
5. The composite metal oxide filler includes at least one of the ZnO–Al2O3 system and the MgO–Al2O3 system.
4. The modified bitumen waterproof membrane according to claim 2, characterized in that, The maleic anhydride-grafted polyolefin resin includes at least one of maleic anhydride-grafted SEBS resin and maleic anhydride-grafted polypropylene resin. The polar rubber is at least one of nitrile rubber and hydrogenated nitrile rubber; The phosphate ester stabilizers include or are selected from one or more of the following compounds: Triphenyl phosphate, trimethylbenzyl phosphate, trinonylphenyl phosphate, triisopropylphenyl phosphate, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphate, tri(2,4-di-tert-butylphenyl) phosphate and trinonylphenyl phosphate.
5. The modified bitumen waterproof membrane according to any one of claims 2-4, characterized in that, The preparation method of the organic ammonium salt modified layered silicate includes the following steps: Step 1: Disperse the layered silicate in deionized water to prepare a suspension with a mass fraction of 3-5 wt%; Step 2: Heat the suspension to 70-80°C and stir to allow the layered silicates to fully expand; Step 3: Add an organic ammonium salt solution to the heated suspension and react at 70℃~80℃ for 2~4 h to carry out cation exchange; Step 4: After cation exchange, the reaction system is filtered, washed, dried, and pulverized to obtain organic ammonium salt modified layered silicate powder; The method for preparing the surface-treated magnesium hydroxide includes the following steps: Step 1, Hydrolysis of coupling agent: The silane coupling agent was added to an ethanol / water mixed solution, and glacial acetic acid was added under stirring to adjust the pH of the system to 4-5, so that the silane coupling agent would undergo a hydrolysis reaction to obtain a hydrolyzed silane solution. Step 2, Surface modification treatment of magnesium hydroxide: Under heating and stirring, the hydrolyzed silane solution from step 1 is sprayed onto the surface of magnesium hydroxide powder to cause the silane coupling agent to undergo a condensation reaction with the hydroxyl groups on the surface of magnesium hydroxide. Then, the powder is dried, pulverized, and sieved to obtain surface silane-treated magnesium hydroxide powder.
6. The modified bitumen waterproof membrane according to claim 5, characterized in that, In the preparation method of the modified layered silicate by the organic ammonium salt, in step 3, the mass of the organic ammonium salt in the organic ammonium salt solution is 1.0 to 1.5 times the cation exchange capacity of the layered silicate; in step 4, the drying temperature is 70 to 85°C and the time is 10 to 15 h. In the preparation method of the surface-treated magnesium hydroxide, in step 1, the volume ratio of ethanol to water in the ethanol / water mixed solution is 3:1 to 5:1, and the hydrolysis reaction time is 20 to 40 min; in step 2, the heating and stirring temperature is 60 to 80℃, and the heating and stirring reaction time is 30 to 60 min; the average particle size of the magnesium hydroxide powder is 0.8 to 3 μm.
7. A method for preparing a modified bitumen waterproof membrane resistant to salt spray and chemical media erosion, characterized in that, Includes the following steps: Step 1: Heat the base asphalt to melt, add the elastomer and shear mix to form a modified asphalt matrix; Step 2: Add polar modifying components to the modified asphalt matrix and continue shearing and mixing; then cool down and add functional fillers and stabilizing agents for mixing to obtain modified asphalt; Step 3: Combine the modified bitumen with the base material, cool and mold to obtain the modified bitumen waterproof membrane.
8. The method for preparing the modified bitumen waterproof membrane according to claim 7, characterized in that, In step 1, the heating temperature to melt is 160~170℃; the shearing temperature for shearing and mixing is 165~180℃, the shearing speed is 1200~1800 rpm, and the shearing time is 10~15 min. In step 2, the shearing time for shear mixing is 10-15 min.
9. The method for preparing the modified bitumen waterproof membrane according to claim 7, characterized in that, In step 2, the functional filler and stabilizing agent are added and mixed after the temperature is lowered to 145~155℃; the mixing speed is lower than the shear speed of the shear mixing in step 1. In step 3, the modified bitumen is combined with the base material by dip coating or calendering, and then cooled and molded to obtain the modified bitumen waterproof membrane.
10. A method for preparing the modified bitumen waterproof membrane according to any one of claims 7-9, characterized in that, In step 3, the thickness of the modified bitumen waterproof membrane is 3.0~4.0 mm, of which the thickness of the base is 0.8~1.2 mm and the thickness of the coating on both sides of the base is 1.0-2.0 mm.