High-temperature-resistant waterproof coating and preparation method thereof

Abstract

The invention relates to the technical field of coatings, and discloses a high-temperature-resistant waterproof coating and a preparation method thereof. The preparation method comprises the following steps: introducing a hydroxyl-terminated nitrile rubber / montmorillonite composite material, 4-(4-hydroxyphenyl) phthalazine-1-ol, N-(4-hydroxyphenyl) maleimide and a perfluorinated chain extender into waterborne polyurethane acrylate; and then free radical polymerization is carried out on the modified starch, carbon-carbon double bond-containing monomer oxazolidinone acrylate, gamma-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate and styrene under the condition of an initiator, and the obtained coating is excellent in high temperature resistance and waterproof performance and good in mechanical property.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to a high temperature resistant waterproof coating and a preparation method thereof. Background Art

[0002] Polyurethane waterproof coatings are highly favored for their excellent performance and are one of the key waterproof materials to be developed. Waterborne polyurethane is an environmentally friendly product that uses water as a solvent. Compared with traditional solvent-based polyurethane coatings, it has the advantages of safety, greenness, and environmental protection. However, due to the introduction of a large number of hydrophilic segments or hydrophilic groups, the water resistance of waterborne polyurethane coatings decreases after coating. In addition, due to the insufficient high temperature resistance of traditional polyurethane-based coatings, they need to be modified.

[0003] Existing technologies such as Chinese patent CN101265318A disclose a high-performance waterborne polyurethane dispersion and its application, which improves the comprehensive properties of waterborne polyurethane such as water resistance and heat resistance by introducing a ring structure into the molecular chain of waterborne polyurethane. However, the heat resistance of the waterborne polyurethane prepared therefrom can still be further improved. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a high temperature resistant waterproof coating and a preparation method thereof, wherein the coating has excellent heat resistance, waterproof properties and good mechanical properties.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A method for preparing a high temperature resistant waterproof coating comprises the following steps:

[0007] Step (1), diphenylmethane diisocyanate and N,N-dimethylformamide are mixed and dissolved, 4-(4-hydroxyphenyl)phthalazine-1-ol and stannous octoate are added, and the reaction is carried out. After the reaction is completed, the temperature is lowered, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material and 2,2-dihydroxymethylpropionic acid are added, and the reaction is continued. After the reaction is completed, a perfluoro chain extender is added, and the reaction is repeated. After the reaction is completed, N-(4-hydroxyphenyl)maleimide is added, and a blocking reaction is carried out. After the reaction is completed, triethylamine is added for neutralization. After neutralization, the temperature is lowered, water is added, and emulsification is carried out to obtain an aqueous polyurethane acrylate emulsion;

[0008] Step (2), dividing the aqueous polyurethane acrylate emulsion into a first emulsion and a second emulsion, mixing the first emulsion, initiator, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene, and reacting. After the reaction is completed, slowly adding the second emulsion, and after the addition is completed, continuing the reaction. After the reaction is completed, a high temperature resistant waterproof coating is obtained.

[0009] Preferably, in the step (1), the mass ratio of diphenylmethane diisocyanate, 4-(4-hydroxyphenyl)phthalazine-1-ol, stannous octoate, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material, 2,2-dihydroxymethylpropionic acid, perfluoro chain extender, and N-(4-hydroxyphenyl)maleimide is 2-3:1.1-1.3:0.05-0.1:20-22:60-65:10-20:2-3:2-3:1-2.

[0010] Preferably, in step (1), the reaction conditions are: reacting in a nitrogen atmosphere at a temperature of 100-110°C for 4-5 hours; continuing the reaction conditions are: continuing the reaction in a nitrogen atmosphere at a temperature of 70-80°C for 2-3 hours; and re-reacting conditions are: reacting again in a nitrogen atmosphere at a temperature of 70-80°C for 1-2 hours.

[0011] Preferably, in step (1), the capping reaction conditions are: in a nitrogen atmosphere at 50-60° C. for 1-2 h; and the neutralization conditions are: at 40-50° C. for 0.5-1 h.

[0012] Preferably, in step (1), the solid content of the aqueous polyurethane acrylate emulsion is 38-44%.

[0013] Preferably, in step (1), the perfluoro chain extender is prepared by mixing 3-perfluoro-n-hexyl-1,2-propylene oxide and ethanolamine in a molar ratio of 2-2.5:1 and reacting them at a temperature of 105-115° C. for 8-9 hours.

[0014] Preferably, the hydroxy-terminated nitrile rubber / montmorillonite composite material in step (1) is prepared by the following steps:

[0015] S11, mixing concentrated sulfuric acid and water evenly, adding montmorillonite, and performing activation treatment. After the treatment, filtering, washing, and drying are completed to obtain acidified montmorillonite;

[0016] S12, mixing the acidified montmorillonite, ethanol and water, performing ultrasonic dispersion, and dropping 3-mercaptopropyltrimethoxysilane. After the dropping is complete, reacting, filtering, washing and drying after the reaction is complete to obtain mercapto-functionalized montmorillonite;

[0017] S13, mixing and stirring the hydroxyl-terminated liquid nitrile rubber, mercapto-functionalized montmorillonite and dichloromethane evenly, adding a photoinitiator, reacting, and after the reaction, removing the solvent dichloromethane by rotary evaporation, washing, and drying to obtain a hydroxyl-terminated nitrile rubber / montmorillonite composite material.

[0018] Preferably, when preparing the hydroxy-terminated nitrile rubber / montmorillonite composite material in step (1), in S11: the mass ratio of concentrated sulfuric acid, water, and montmorillonite is 100:50-60:35-45, and the concentrated sulfuric acid is 98wt% concentrated sulfuric acid; the activation conditions are: stirring and activating at 85-95°C for 3-4h.

[0019] Preferably, when preparing the hydroxy-terminated nitrile rubber / montmorillonite composite material in step (1), in S12: the mass ratio of acidified montmorillonite, ethanol, water, and 3-mercaptopropyltrimethoxysilane is 1:20-25:20-25:0.8-1; and the reaction conditions are: stirring the reaction at room temperature for 6-8 hours.

[0020] Preferably, when preparing the hydroxy-terminated nitrile rubber / montmorillonite composite material in step (1), in S13: the mass ratio of the hydroxy-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite, the dichloromethane, and the photoinitiator is 10:4-5:40-50:0.4-0.5; and the reaction conditions are: stirring the reaction at room temperature in an ultraviolet lamp environment with a wavelength of 365 nm for 10-14 hours.

[0021] Preferably, the photoinitiator comprises alpha-hydroxyisobutyrophenone.

[0022] Preferably, in step (2), the mass ratio of the first emulsion, the second emulsion, the initiator, the oxazolidinone acrylate, the γ-methacryloxypropyltrimethoxysilane, the hexafluorobutyl methacrylate and the styrene is 30-40:65-75:2-3:20-25:1-2:5-10:3-5; the reaction conditions are: reacting at a temperature of 60-70°C for 0.5-1h; the addition time of the second emulsion is 1.5-2h; and the continued reaction conditions are: continuing the reaction at a temperature of 65-75°C for 3-4h.

[0023] Preferably, the initiator comprises azobisisobutyronitrile.

[0024] Preferably, the oxazolidinone acrylate in step (2) is prepared by the following steps:

[0025] Neopentyl glycol diacrylate, 3-(2-hydroxyethyl)-2-oxazolidinone and potassium carbonate are mixed and reacted. After the reaction is completed, the temperature is lowered, the mixture is filtered, and the filtrate is collected and dried to obtain oxazolidinone acrylate.

[0026] Preferably, when preparing oxazolidinone acrylate in step (2), the mass ratio of neopentyl glycol diacrylate, 3-(2-hydroxyethyl)-2-oxazolidinone and potassium carbonate is 42-48:26-30:3.4-3.9; and the reaction conditions are: reacting at a temperature of 45-55° C. for 16-18 hours.

[0027] Preferably, a high temperature resistant waterproof coating is prepared using the method for preparing the high temperature resistant waterproof coating as described above.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The present invention prepares a heat-resistant and water-resistant terminal hydroxyl nitrile rubber / montmorillonite composite material, introduces the composite material into waterborne polyurethane acrylate with 4-(4-hydroxyphenyl)phthalazine-1-ol having a phthalazinyl biphenyl structure, N-(4-hydroxyphenyl)maleimide having a maleimide group, and a perfluorinated chain extender, and then free radical polymerizes the composite material with carbon-carbon double bond-containing monomers oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene under initiator conditions, so that the obtained coating has excellent high temperature resistance and waterproof performance, and good mechanical properties.

[0030] The hydroxyl-terminated liquid nitrile rubber is a liquid synthetic rubber containing hydroxyl functional groups at both ends, which is prepared by copolymerizing butadiene and acrylonitrile. The molecular chain has both non-polar and highly polar segments, and has excellent oil resistance, water resistance, aging resistance and bonding properties. Introducing the hydroxyl-terminated liquid nitrile rubber into waterborne polyurethane acrylate can improve the mechanical properties, water resistance and bonding properties of the coating. The present invention treats the surface of montmorillonite with 3-mercaptopropyltrimethoxysilane after acid treatment to obtain mercapto-functionalized montmorillonite. The mercapto groups on the surface of the mercapto-functionalized montmorillonite and the unsaturated double bonds in the hydroxyl-terminated liquid nitrile rubber are activated under the action of a photoinitiator. The thiol-olefin click chemistry reaction connects the hydroxyl-terminated liquid nitrile rubber and the thiol-functionalized montmorillonite through chemical bonds. Since the hydroxyl-terminated liquid nitrile rubber has terminal hydroxyl groups, the obtained hydroxyl-terminated nitrile rubber / montmorillonite composite material can be used as a polyhydroxy polymer to participate in the polymerization reaction of waterborne polyurethane acrylate, thereby improving the dispersibility and compatibility of montmorillonite in the waterborne polyurethane acrylate matrix. In addition, since the lamellar structure of montmorillonite can be evenly dispersed in the matrix, it has a certain shielding effect on water and heat, and can delay the aging and chain breaking of the polyurethane acrylate molecular chain, thereby further improving the heat-resistant and waterproof properties of the matrix.

[0031] The invention introduces 4-(4-hydroxyphenyl)phthalazine-1-ol, terminal hydroxyl nitrile rubber / montmorillonite composite material and N-(4-hydroxyphenyl)maleimide into polyurethane acrylate, and then the prepared aqueous polyurethane acrylate emulsion and acrylate monomer undergo free radical polymerization under the condition of an initiator, thereby increasing the crosslinking degree of the base material and obtaining a high temperature resistant waterproof coating.

[0032] Among them, the perfluorinated chain extender is prepared by the ring-opening reaction of 3-perfluoro-n-hexyl-1,2-propylene oxide and ethanolamine. Introducing it into the matrix material can improve the hydrophobicity of the material; 4-(4-hydroxyphenyl)phthalazine-1-ol has a rigid heterocyclic naphthalene biphenyl structure, and N-(4-hydroxyphenyl) maleimide contains hydroxyl and vinyl imide rings, which can react with the terminal isocyanate group of the polyurethane prepolymer and copolymerize with the acrylate monomer. Introducing the two into the matrix can synergistically improve the high temperature resistance and mechanical properties of the material;

[0033] Among the acrylic ester monomers, oxazolidinone acrylate contains an oxazolidinone heterocyclic structure and a carbon-carbon double bond. It is prepared by the Michael addition reaction between neopentyl glycol diacrylate and 3-(2-hydroxyethyl)-2-oxazolidinone using the carbon-carbon double bond and the hydroxyl group. Introducing it into the matrix material can further improve the heat resistance of the material; γ-methacryloxypropyltrimethoxysilane as a tackifier can improve the adhesion of the coating; hexafluorobutyl methacrylate as a fluorine-containing compound, together with the perfluorinated chain extender, improves the waterproof and hydrophobic properties of the coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a process flow chart for preparing high temperature resistant waterproof coating in the present invention;

[0035] Figure 2 It is a histogram of impact strength of the embodiments and comparative examples of the present invention in performance tests;

[0036] Figure 3 It is a bar graph of water absorption rate of the embodiments and comparative examples in the performance test of the present invention. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0038] Example 1

[0039] This embodiment discloses a method for preparing a high temperature resistant waterproof coating, comprising the following steps:

[0040] Step (1), diphenylmethane diisocyanate and N,N-dimethylformamide are mixed and dissolved in a mass ratio of 1:4, 4-(4-hydroxyphenyl)phthalazine-1-ol and a catalyst stannous octoate are added, and the mixture is reacted at a temperature of 100° C. for 5 hours in a nitrogen atmosphere. After the reaction is completed, the temperature is lowered, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material and 2,2-dihydroxymethylpropionic acid are added, and the reaction is continued at a temperature of 70° C. for 3 hours. After the reaction is completed, a perfluoro chain extender is added, and the mixture is reacted again at a temperature of 70° C. for 2 hours. After the reaction is completed, a blocking agent N-(4-hydroxyphenyl)maleimide is added, and the blocking reaction is carried out at a temperature of 50° C. for 2 hours. After the blocking reaction is completed, triethylamine is added, and the mixture is neutralized at a temperature of 40° C. for 1 hour. After neutralization to neutrality, the mixture is cooled to room temperature, water is added, and the mixture is dispersed and emulsified with high-speed stirring for 1 hour to obtain an aqueous polyurethane acrylate emulsion with a solid content of 38%;

[0041] The mass ratio of diphenylmethane diisocyanate, 4-(4-hydroxyphenyl)phthalazine-1-ol, stannous octoate, isophorone diisocyanate, polytetramethylene ether diol, hydroxy-terminated nitrile rubber / montmorillonite composite material, 2,2-dihydroxymethylpropionic acid, perfluorinated chain extender, and N-(4-hydroxyphenyl)maleimide is 2:1.1:0.05:20:65:10:2:2:1;

[0042] The perfluoro chain extender is prepared by mixing 3-perfluoro-n-hexyl-1,2-propylene oxide and ethanolamine in a molar ratio of 2:1 and reacting at a temperature of 105°C for 9 hours;

[0043] The hydroxy-terminated nitrile rubber / montmorillonite composite material is prepared by the following steps:

[0044] S11, 98wt% concentrated sulfuric acid and water are mixed evenly, and montmorillonite is added, the mass ratio of 98wt% concentrated sulfuric acid, water, and montmorillonite is 100:55:40, and the mixture is stirred and activated at 90°C for 3.5h. After the treatment, the mixture is filtered, the filter cake is taken, and water 7 times the mass of the filter cake is added to wash the mixture until it is neutral, and the mixture is dried at 105°C for 10h to obtain acidified montmorillonite;

[0045] S12, the acidified montmorillonite, ethanol and water were mixed, ultrasonically dispersed for 1.5 hours, 3-mercaptopropyltrimethoxysilane was added dropwise, the addition time was 15 minutes, the mass ratio of the acidified montmorillonite, ethanol, water and 3-mercaptopropyltrimethoxysilane was 1:23:22:0.9, after the addition was completed, the reaction was stirred at room temperature for 7 hours, after the reaction was completed, the filter cake was taken, ethanol and water with a mass of 6 times the mass of the filter cake were added in turn, washed until neutral, and dried at 75°C for 16 hours to obtain mercapto-functionalized montmorillonite;

[0046] S13, mixing and stirring the hydroxyl-terminated liquid nitrile rubber, mercapto-functionalized montmorillonite, and dichloromethane, adding a photoinitiator α-hydroxyisobutyrophenone, the mass ratio of hydroxyl-terminated liquid nitrile rubber, mercapto-functionalized montmorillonite, dichloromethane, and α-hydroxyisobutyrophenone being 10:4:40:0.4, stirring and reacting for 10 hours at room temperature in an ultraviolet lamp environment with a wavelength of 365nm, after the reaction is completed, removing the solvent dichloromethane by rotary evaporation at a temperature of 20°C to obtain a reaction product, adding ethanol 5 times the mass of the reaction product to wash three times, and drying at a temperature of 50°C for 24 hours to obtain a hydroxyl-terminated nitrile rubber / montmorillonite composite material;

[0047] Step (2), dividing the aqueous polyurethane acrylate emulsion into a first emulsion and a second emulsion, mixing the first emulsion, initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene, and reacting at 60° C. for 1 hour. After the reaction is completed, slowly adding the second emulsion for 1.5 hours. After the addition is completed, continuing the reaction at 65° C. for 4 hours. After the reaction is completed, a high temperature resistant waterproof coating is obtained;

[0048] The mass ratio of the first emulsion, the second emulsion, the initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene is 30:75:2:20:1:5:3;

[0049] Oxazolidinone acrylate is prepared by the following steps:

[0050] Neopentyl glycol diacrylate, 3-(2-hydroxyethyl)-2-oxazolidinone and potassium carbonate were mixed in a mass ratio of 45:28:3.6, and reacted at 50°C for 17 hours. After the reaction, the mixture was cooled to room temperature, filtered, and the filtrate was dried at 55°C for 16 hours to obtain oxazolidinone acrylate.

[0051] Example 2

[0052] This embodiment discloses a method for preparing a high temperature resistant waterproof coating, comprising the following steps:

[0053] Step (1), diphenylmethane diisocyanate and N,N-dimethylformamide are mixed and dissolved in a mass ratio of 1:4, 4-(4-hydroxyphenyl)phthalazine-1-ol and a catalyst stannous octoate are added, and the mixture is reacted in a nitrogen atmosphere at a temperature of 100° C. for 4.5 hours. After the reaction is completed, the temperature is lowered, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material and 2,2-dihydroxymethylpropionic acid are added, and the reaction is continued at a temperature of 70° C. for 2.5 hours. After the reaction is completed, a perfluoro chain extender is added, and the mixture is reacted again at a temperature of 70° C. for 1.5 hours. After the reaction is completed, a blocking agent N-(4-hydroxyphenyl)maleimide is added, and the blocking reaction is carried out at a temperature of 50° C. for 1.5 hours. After the blocking reaction is completed, triethylamine is added, and the mixture is neutralized at a temperature of 40° C. for 0.5 hours. After neutralization to neutrality, the mixture is cooled to room temperature, water is added, and the mixture is dispersed and emulsified with high-speed stirring for 1 hour to obtain an aqueous polyurethane acrylate emulsion with a solid content of 39%;

[0054] Among them, the mass ratio of diphenylmethane diisocyanate, 4-(4-hydroxyphenyl)phthalazine-1-ol, stannous octoate, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material, 2,2-dihydroxymethylpropionic acid, perfluorinated chain extender, and N-(4-hydroxyphenyl)maleimide is 2.3:1.15:0.08:20.5:64:13:2.3:2.3:1.3;

[0055] The perfluoro chain extender is prepared by mixing 3-perfluoro-n-hexyl-1,2-propylene oxide and ethanolamine in a molar ratio of 2.2:1 and reacting at a temperature of 105°C for 8.5 hours;

[0056] The hydroxy-terminated nitrile rubber / montmorillonite composite material is prepared by the following steps:

[0057] The hydroxyl-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite and dichloromethane were mixed and stirred uniformly, and a photoinitiator α-hydroxyisobutyrophenone was added, and the mass ratio of the hydroxyl-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite, the dichloromethane and the α-hydroxyisobutyrophenone was 10:4.3:42:0.42, and the reaction was stirred for 12 hours at room temperature in an ultraviolet lamp environment with a wavelength of 365nm. After the reaction was completed, the solvent dichloromethane was removed by rotary evaporation at a temperature of 20°C to obtain a reaction product, and ethanol 6 times the mass of the reaction product was added for washing three times, and the product was dried at a temperature of 55°C for 22 hours to obtain a hydroxyl-terminated nitrile rubber / montmorillonite composite material; wherein the preparation of the mercapto-functionalized montmorillonite is the same as that in Example 1;

[0058] Step (2), dividing the aqueous polyurethane acrylate emulsion into a first emulsion and a second emulsion, mixing the first emulsion, initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene, and reacting at 65° C. for 0.5 h. After the reaction is completed, slowly adding the second emulsion for 2 h. After the addition is completed, continuing the reaction at 70° C. for 3 h. After the reaction is completed, a high temperature resistant waterproof coating is obtained;

[0059] Among them, the mass ratio of the first emulsion, the second emulsion, the initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene is 33:72:2.3:22:1.3:6:3.5; the preparation of oxazolidinone acrylate is the same as that in Example 1.

[0060] Example 3

[0061] This embodiment discloses a method for preparing a high temperature resistant waterproof coating, comprising the following steps:

[0062] Step (1), diphenylmethane diisocyanate and N,N-dimethylformamide are mixed and dissolved in a mass ratio of 1:4.5, 4-(4-hydroxyphenyl)phthalazine-1-ol and a catalyst stannous octoate are added, and the mixture is reacted at a temperature of 105° C. for 4.5 hours in a nitrogen atmosphere. After the reaction is completed, the temperature is lowered, and isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material and 2,2-dihydroxymethylpropionic acid are added, and the reaction is continued at a temperature of 75° C. After the reaction is completed, a perfluoro chain extender is added, and the reaction is continued at 75°C for 1.5h. After the reaction is completed, a capping agent N-(4-hydroxyphenyl)maleimide is added, and the capping reaction is carried out at 55°C for 1.5h. After the capping reaction is completed, triethylamine is added, and the neutralization reaction is carried out at 45°C for 0.5h. After neutralization to neutrality, the temperature is lowered to room temperature, water is added, and the mixture is dispersed and emulsified with high-speed stirring for 1h to obtain an aqueous polyurethane acrylate emulsion with a solid content of 40%;

[0063] Among them, the mass ratio of diphenylmethane diisocyanate, 4-(4-hydroxyphenyl)phthalazine-1-ol, stannous octoate, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material, 2,2-dihydroxymethylpropionic acid, perfluorinated chain extender, and N-(4-hydroxyphenyl)maleimide is 2.5:1.2:0.08:21:63:15:2.5:2.5:1.5;

[0064] The perfluoro chain extender is prepared by mixing 3-perfluoro-n-hexyl-1,2-propylene oxide and ethanolamine in a molar ratio of 2.3:1 and reacting at a temperature of 110°C for 8.5 hours;

[0065] The hydroxy-terminated nitrile rubber / montmorillonite composite material is prepared by the following steps:

[0066] The hydroxyl-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite and dichloromethane were mixed and stirred evenly, and a photoinitiator α-hydroxyisobutyrophenone was added, and the mass ratio of the hydroxyl-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite, the dichloromethane and the α-hydroxyisobutyrophenone was 10:4.5:45:0.45, and the mixture was stirred and reacted for 12 hours at room temperature in an ultraviolet lamp environment with a wavelength of 365nm. After the reaction was completed, the solvent dichloromethane was removed by rotary evaporation at a temperature of 25°C to obtain a reaction product, and ethanol 6 times the mass of the reaction product was added for washing three times, and the mixture was dried at a temperature of 55°C for 22 hours to obtain a hydroxyl-terminated nitrile rubber / montmorillonite composite material; wherein the preparation of the mercapto-functionalized montmorillonite was the same as that in Example 1;

[0067] Step (2), dividing the aqueous polyurethane acrylate emulsion into a first emulsion and a second emulsion, mixing the first emulsion, initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene, and reacting at 65° C. for 0.5 h. After the reaction is completed, slowly adding the second emulsion for 2 h. After the addition is completed, continuing the reaction at 70° C. for 3.5 h. After the reaction is completed, a high temperature resistant waterproof coating is obtained;

[0068] Among them, the mass ratio of the first emulsion, the second emulsion, the initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene is 35:70:2.5:23:1.5:8:4; the preparation of oxazolidinone acrylate is the same as that in Example 1.

[0069] Example 4

[0070] This embodiment discloses a method for preparing a high temperature resistant waterproof coating, comprising the following steps:

[0071] Step (1), diphenylmethane diisocyanate and N,N-dimethylformamide are mixed and dissolved in a mass ratio of 1:5, 4-(4-hydroxyphenyl)phthalazine-1-ol and a catalyst stannous octoate are added, and the mixture is reacted in a nitrogen atmosphere at a temperature of 110° C. for 4.5 hours. After the reaction is completed, the temperature is lowered, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material and 2,2-dihydroxymethylpropionic acid are added, and the reaction is continued at a temperature of 80° C. for 2.5 hours. After the reaction is completed, a perfluoro chain extender is added, and the mixture is reacted again at a temperature of 80° C. for 1.5 hours. After the reaction is completed, a blocking agent N-(4-hydroxyphenyl)maleimide is added, and the blocking reaction is carried out at a temperature of 60° C. for 1.5 hours. After the blocking reaction is completed, triethylamine is added, and the mixture is neutralized at a temperature of 50° C. for 0.5 hours. After neutralization to neutrality, the mixture is cooled to room temperature, water is added, and the mixture is dispersed and emulsified with high-speed stirring for 1 hour to obtain an aqueous polyurethane acrylate emulsion with a solid content of 42%;

[0072] Among them, the mass ratio of diphenylmethane diisocyanate, 4-(4-hydroxyphenyl)phthalazine-1-ol, stannous octoate, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material, 2,2-dihydroxymethylpropionic acid, perfluorinated chain extender, and N-(4-hydroxyphenyl)maleimide is 2.8:1.25:0.08:21.5:62:18:2.8:2.8:1.8;

[0073] The perfluoro chain extender is prepared by mixing 3-perfluoro-n-hexyl-1,2-propylene oxide and ethanolamine in a molar ratio of 2.4:1 and reacting at a temperature of 115°C for 8.5 hours;

[0074] The hydroxy-terminated nitrile rubber / montmorillonite composite material is prepared by the following steps:

[0075] The hydroxyl-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite and dichloromethane were mixed and stirred uniformly, and a photoinitiator α-hydroxyisobutyrophenone was added, and the mass ratio of the hydroxyl-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite, the dichloromethane and the α-hydroxyisobutyrophenone was 10:4.8:48:0.48, and the reaction was stirred for 12 hours at room temperature in an ultraviolet lamp environment with a wavelength of 365nm. After the reaction was completed, the solvent dichloromethane was removed by rotary evaporation at a temperature of 30°C to obtain a reaction product, and ethanol 6 times the mass of the reaction product was added for washing three times, and dried at a temperature of 55°C for 22 hours to obtain a hydroxyl-terminated nitrile rubber / montmorillonite composite material; wherein the preparation of the mercapto-functionalized montmorillonite is the same as that in Example 1;

[0076] Step (2), dividing the aqueous polyurethane acrylate emulsion into a first emulsion and a second emulsion, mixing the first emulsion, initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene, and reacting at 70° C. for 0.5 h. After the reaction is completed, slowly adding the second emulsion for 2 h. After the addition is completed, continuing the reaction at 75° C. for 3.5 h. After the reaction is completed, a high temperature resistant waterproof coating is obtained;

[0077] Among them, the mass ratio of the first emulsion, the second emulsion, the initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene is 38:67:2.8:24:1.8:9:4.5; the preparation of oxazolidinone acrylate is the same as that in Example 1.

[0078] Example 5

[0079] This embodiment discloses a method for preparing a high temperature resistant waterproof coating, comprising the following steps:

[0080] Step (1), diphenylmethane diisocyanate and N,N-dimethylformamide are mixed and dissolved in a mass ratio of 1:5, 4-(4-hydroxyphenyl)phthalazine-1-ol and a catalyst stannous octoate are added, and the mixture is reacted in a nitrogen atmosphere at a temperature of 110° C. for 4 hours. After the reaction is completed, the temperature is lowered, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material and 2,2-dihydroxymethylpropionic acid are added, and the reaction is continued at a temperature of 80° C. for 2 hours. After the reaction is completed, a perfluoro chain extender is added, and the mixture is reacted again at a temperature of 80° C. for 1 hour. After the reaction is completed, a blocking agent N-(4-hydroxyphenyl)maleimide is added, and the blocking reaction is carried out at a temperature of 60° C. for 1 hour. After the blocking reaction is completed, triethylamine is added, and the mixture is neutralized at a temperature of 50° C. for 0.5 hour. After neutralization to neutrality, the mixture is cooled to room temperature, water is added, and the mixture is dispersed and emulsified with high-speed stirring for 1.5 hours to obtain an aqueous polyurethane acrylate emulsion with a solid content of 44%;

[0081] The mass ratio of diphenylmethane diisocyanate, 4-(4-hydroxyphenyl)phthalazine-1-ol, stannous octoate, isophorone diisocyanate, polytetramethylene ether diol, hydroxy-terminated nitrile rubber / montmorillonite composite material, 2,2-dihydroxymethylpropionic acid, perfluorinated chain extender, and N-(4-hydroxyphenyl)maleimide is 3:1.3:0.1:22:60:20:3:3:2;

[0082] The perfluoro chain extender is prepared by mixing 3-perfluoro-n-hexyl-1,2-propylene oxide and ethanolamine in a molar ratio of 2.5:1 and reacting at a temperature of 115°C for 8 hours;

[0083] The hydroxy-terminated nitrile rubber / montmorillonite composite material is prepared by the following steps:

[0084] The hydroxyl-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite and dichloromethane were mixed and stirred uniformly, and a photoinitiator α-hydroxyisobutyrophenone was added, and the mass ratio of the hydroxyl-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite, the dichloromethane and the α-hydroxyisobutyrophenone was 10:5:50:0.5. The mixture was stirred and reacted for 14 hours at room temperature in an ultraviolet lamp environment with a wavelength of 365 nm. After the reaction was completed, the solvent dichloromethane was removed by rotary evaporation at a temperature of 30° C. to obtain a reaction product, and ethanol 8 times the mass of the reaction product was added for washing three times, and the mixture was dried at a temperature of 60° C. for 20 hours to obtain a hydroxyl-terminated nitrile rubber / montmorillonite composite material; wherein the preparation of the mercapto-functionalized montmorillonite was the same as that in Example 1;

[0085] Step (2), dividing the aqueous polyurethane acrylate emulsion into a first emulsion and a second emulsion, mixing the first emulsion, initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene, and reacting at 70° C. for 0.5 h. After the reaction is completed, slowly adding the second emulsion for 2 h. After the addition is completed, continuing the reaction at 75° C. for 3 h. After the reaction is completed, a high temperature resistant waterproof coating is obtained;

[0086] Among them, the mass ratio of the first emulsion, the second emulsion, the initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene is 40:65:3:25:2:10:5; the preparation of oxazolidinone acrylate is the same as that in Example 1.

[0087] Comparative Example 1

[0088] This comparative example discloses a method for preparing a coating, comprising the following steps:

[0089] Step (1), diphenylmethane diisocyanate and N,N-dimethylformamide are mixed and dissolved in a mass ratio of 1:4, 4-(4-hydroxyphenyl)phthalazine-1-ol and a catalyst stannous octoate are added, and the mixture is reacted at a temperature of 100° C. for 5 hours in a nitrogen atmosphere. After the reaction is completed, the temperature is lowered, isophorone diisocyanate, polytetramethylene glycol and 2,2-dihydroxymethylpropionic acid are added, and the reaction is continued at a temperature of 70° C. for 3 hours. After the reaction is completed, a perfluoro chain extender is added, and the mixture is reacted again at a temperature of 70° C. for 2 hours. After the reaction is completed, a blocking agent N-(4-hydroxyphenyl)maleimide is added, and the blocking reaction is carried out at a temperature of 50° C. for 2 hours. After the blocking reaction is completed, triethylamine is added, and the mixture is neutralized at a temperature of 40° C. for 1 hour. After neutralization to neutrality, the mixture is cooled to room temperature, water is added, and the mixture is dispersed and emulsified with high-speed stirring for 1 hour to obtain an aqueous polyurethane acrylate emulsion with a solid content of 38%;

[0090] The mass ratio of diphenylmethane diisocyanate, 4-(4-hydroxyphenyl)phthalazine-1-ol, stannous octoate, isophorone diisocyanate, polytetramethylene glycol, 2,2-dihydroxymethylpropionic acid, perfluorinated chain extender, and N-(4-hydroxyphenyl)maleimide is 2:1.1:0.05:20:75:2:2:1;

[0091] The perfluoro chain extender is prepared by mixing 3-perfluoro-n-hexyl-1,2-propylene oxide and ethanolamine in a molar ratio of 2:1 and reacting at a temperature of 105°C for 9 hours;

[0092] Step (2), dividing the aqueous polyurethane acrylate emulsion into a first emulsion and a second emulsion, mixing the first emulsion, initiator azobisisobutyronitrile, methyl methacrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene, and reacting at 60° C. for 1 hour. After the reaction is completed, slowly adding the second emulsion for 1.5 hours. After the addition is completed, continuing the reaction at 65° C. for 4 hours. After the reaction is completed, a coating is obtained;

[0093] Among them, the mass ratio of the first emulsion, the second emulsion, the initiator azobisisobutyronitrile, methyl methacrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene is 30:75:2:20:1:5:3.

[0094] Comparative Example 2

[0095] This comparative example discloses a method for preparing a coating, comprising the following steps:

[0096] Step (1), diphenylmethane diisocyanate and N,N-dimethylformamide are mixed and dissolved in a mass ratio of 1:4, 4-(4-hydroxyphenyl)phthalazine-1-ol and a catalyst stannous octoate are added, and the mixture is reacted at a temperature of 100° C. for 5 hours in a nitrogen atmosphere. After the reaction is completed, the temperature is lowered, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material and 2,2-dihydroxymethylpropionic acid are added, and the reaction is continued at a temperature of 70° C. for 3 hours. After the reaction is completed, 1,4-ethylene glycol is added, and the mixture is reacted again at a temperature of 70° C. for 2 hours. After the reaction is completed, a blocking agent N-(4-hydroxyphenyl)maleimide is added, and the blocking reaction is carried out at a temperature of 50° C. for 2 hours. After the blocking reaction is completed, triethylamine is added, and the mixture is neutralized at a temperature of 40° C. for 1 hour. After neutralization to neutrality, the mixture is cooled to room temperature, water is added, and the mixture is dispersed and emulsified with high-speed stirring for 1 hour to obtain an aqueous polyurethane acrylate emulsion with a solid content of 38%;

[0097] The mass ratio of diphenylmethane diisocyanate, 4-(4-hydroxyphenyl)phthalazine-1-ol, stannous octoate, isophorone diisocyanate, polytetramethylene ether diol, hydroxy-terminated nitrile rubber / montmorillonite composite material, 2,2-dihydroxymethylpropionic acid, 1,4-ethylene glycol, and N-(4-hydroxyphenyl)maleimide is 2:1.1:0.05:20:65:10:2:2:1;

[0098] The hydroxy-terminated nitrile rubber / montmorillonite composite material is prepared by the following steps:

[0099] The hydroxyl-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite and dichloromethane were mixed and stirred uniformly, and a photoinitiator α-hydroxyisobutyrophenone was added, and the mass ratio of the hydroxyl-terminated liquid nitrile rubber, the mercapto-functionalized montmorillonite, the dichloromethane and the α-hydroxyisobutyrophenone was 10:4:40:0.4, and the mixture was stirred and reacted for 10 hours at room temperature in an ultraviolet lamp environment with a wavelength of 365nm. After the reaction was completed, the solvent dichloromethane was removed by rotary evaporation at a temperature of 20°C to obtain a reaction product, and ethanol 5 times the mass of the reaction product was added for washing three times, and the mixture was dried at a temperature of 50°C for 24 hours to obtain a hydroxyl-terminated nitrile rubber / montmorillonite composite material; wherein the preparation of the mercapto-functionalized montmorillonite was the same as that in Example 1;

[0100] Step (2), dividing the aqueous polyurethane acrylate emulsion into a first emulsion and a second emulsion, mixing the first emulsion, initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, methyl methacrylate, and styrene, and reacting at 60° C. for 1 hour. After the reaction is completed, slowly adding the second emulsion for 1.5 hours. After the addition is completed, continuing the reaction at 65° C. for 4 hours. After the reaction is completed, a coating is obtained;

[0101] Among them, the mass ratio of the first emulsion, the second emulsion, the initiator azobisisobutyronitrile, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, methyl methacrylate, and styrene is 30:75:2:20:1:5:3; the preparation of oxazolidinone acrylate is the same as that in Example 1.

[0102] In the above examples and comparative examples: 4-(4-hydroxyphenyl)phthalazin-1-ol is from Chongqing Futeng Pharmaceutical Co., Ltd., CAS No.: 152594-70-2; polytetrahydrofuran ether glycol is from Shanghai Aladdin Biochemical Technology Co., Ltd., Mn = 2900; N-(4-hydroxyphenyl) maleimide is from Shanghai MacLean Biochemical Technology Co., Ltd., CAS No.: 7300-91-6; 3-perfluoro-n-hexyl-1,2-epoxypropane is from Wuhan Kemik Biopharmaceutical Technology Co., Ltd., CAS No.: 38565-52-5; montmorillonite is from Zhejiang Lin'an Qishi Bentonite Chemical Co., Ltd., product name sodium montmorillonite, particle size 50μm; 3-mercaptopropyltrimethoxysilane is from AlfaAesar , CAS number: 4420-74-0; hydroxyl-terminated liquid nitrile rubber comes from Zibo Qilong Chemical Co., Ltd., product name hydroxyl-terminated polybutadiene acrylonitrile HTBN, hydroxyl value 0.62mmol / g, number average molecular weight 2000; γ-methacryloxypropyltrimethoxysilane comes from Hangzhou Jessica Chemical Co., Ltd., product name silane coupling agent KH-570; hexafluorobutyl methacrylate comes from Wuhan Lanabai Pharmaceutical Chemical Co., Ltd., CAS number: 36405-47-7; neopentyl glycol diacrylate comes from Guangdong Fangxin Biotechnology Co., Ltd., CAS number: 2223-82-7; 3-(2-hydroxyethyl)-2-oxazolidinone comes from Xi'an Qiyue Biotechnology Co., Ltd., CAS number: 3356-88-5.

[0103] Test example

[0104] The coatings prepared in the above embodiments and comparative examples were tested for performance, and the specific test results are shown in Table 1:

[0105] Table 1

[0106]

[0107]

[0108] The detection of each index in Table 1 is based on the following standards: adhesion is measured with reference to GB / T1720-1989 "Determination of paint film adhesion"; impact strength is measured with reference to GB / T1732-2020 "Determination of paint film impact resistance"; water absorption is measured with reference to HGT3344-1985 "Determination of paint film water absorption"; heat resistance is represented by thermal weight loss temperature and paint film surface phenomenon, wherein the thermal weight loss temperature is measured by STA449F3 synchronous thermal analyzer in a nitrogen atmosphere, the test temperature is 50-600°C, the heating rate is 20K / min, and the weight loss rate is 5%; the paint film surface phenomenon is measured by observing the paint film surface phenomenon after drying the embodiment and comparative example coatings at 300°C for a certain period of time.

[0109] It can be seen from the test results in Table 1 that the coating prepared by the present invention has excellent high temperature resistance and waterproof performance, and good mechanical properties.

[0110] In the present invention, the hydroxyl-terminated liquid nitrile rubber has excellent oil resistance, water resistance, aging resistance and bonding properties, and can improve the mechanical properties, water resistance and bonding properties of the coating. The hydroxyl-terminated nitrile rubber / montmorillonite composite material in the present invention can participate in the polymerization reaction of waterborne polyurethane acrylate as a polyhydroxy polymer, thereby improving the dispersibility and compatibility of montmorillonite in the waterborne polyurethane acrylate matrix. In addition, since the lamella structure of montmorillonite can be evenly dispersed in the matrix, it has a certain shielding effect on water and heat, and can delay the aging and chain breaking of the polyurethane acrylate molecular chain, thereby further improving the heat resistance and waterproof performance of the matrix.

[0111] 4-(4-Hydroxyphenyl)phthalazin-1-ol has a rigid heterocyclic naphthalene biphenyl structure, and N-(4-hydroxyphenyl)maleimide contains a vinylimide ring. Introducing the two into the matrix can synergistically improve the high temperature resistance and mechanical properties of the material; among the acrylic ester monomers, oxazolidinone acrylate contains an oxazolidinone heterocyclic structure and a carbon-carbon double bond, and introducing it into the matrix material can further improve the heat resistance of the material; γ-methacryloxypropyltrimethoxysilane as a tackifier can improve the adhesion performance of the coating; hexafluorobutyl methacrylate as a fluorine-containing compound, together with the perfluorinated chain extender, improves the waterproof and hydrophobic properties of the coating.

[0112] In Comparative Example 1, no hydroxy-terminated nitrile rubber / montmorillonite composite material is added, and oxazolidinone acrylate is replaced by methyl methacrylate. The montmorillonite lamellar structure lacks the effect of improving the heat resistance and water resistance of the coating, and the hydroxy-terminated nitrile rubber lacks the effect of improving the adhesion of the coating; the oxazolidinone acrylate lacks the effect of improving the heat resistance of the coating, so the adhesion, mechanical properties, heat resistance and water resistance of Comparative Example 1 are all reduced;

[0113] In Comparative Example 2, the perfluoro chain extender is replaced by 1,4-ethylene glycol, and hexafluorobutyl methacrylate is replaced by methyl methacrylate. The fluorinated compounds are lacking in improving the hydrophobic properties of the coating, so the waterproof performance of Comparative Example 2 is reduced.

[0114] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a high temperature resistant waterproof coating, characterized in that: The following steps are involved: Step (1), diphenylmethane diisocyanate and N,N-dimethylformamide are mixed and dissolved, 4-(4-hydroxyphenyl)phthalazine-1-ol and stannous octoate are added, and the reaction is carried out. After the reaction is completed, the temperature is lowered, isophorone diisocyanate, polytetramethylene glycol, hydroxy-terminated nitrile rubber / montmorillonite composite material and 2,2-dihydroxymethylpropionic acid are added, and the reaction is continued. After the reaction is completed, a perfluoro chain extender is added, and the reaction is repeated. After the reaction is completed, N-(4-hydroxyphenyl)maleimide is added, and a blocking reaction is carried out. After the reaction is completed, triethylamine is added for neutralization. After neutralization, the temperature is lowered, water is added, and emulsification is carried out to obtain an aqueous polyurethane acrylate emulsion; Step (2), dividing the aqueous polyurethane acrylate emulsion into a first emulsion and a second emulsion, mixing the first emulsion, initiator, oxazolidinone acrylate, γ-methacryloxypropyltrimethoxysilane, hexafluorobutyl methacrylate, and styrene, and reacting. After the reaction is completed, slowly adding the second emulsion, and after the addition is completed, continuing the reaction. After the reaction is completed, a high temperature resistant waterproof coating is obtained.

2. The method for preparing a high temperature resistant waterproof coating according to claim 1, characterized in that: In the step (1), the mass ratio of diphenylmethane diisocyanate, 4-(4-hydroxyphenyl)phthalazine-1-ol, stannous octoate, isophorone diisocyanate, polytetramethylene glycol, terminal hydroxyl nitrile rubber / montmorillonite composite material, 2,2-dihydroxymethylpropionic acid, perfluoro chain extender, and N-(4-hydroxyphenyl)maleimide is 2-3:1.1-1.3:0.05-0.1:20-22:60-65:10-20:2-3:2-3:1-2; and the solid content of the aqueous polyurethane acrylate emulsion is 38-44%.

3. The method for preparing a high temperature resistant waterproof coating according to claim 1, characterized in that: In the step (1), the reaction conditions are: reacting in a nitrogen atmosphere at a temperature of 100-110° C. for 4-5 hours; continuing the reaction conditions are: continuing the reaction in a nitrogen atmosphere at a temperature of 70-80° C. for 2-3 hours; re-reacting conditions are: reacting again in a nitrogen atmosphere at a temperature of 70-80° C. for 1-2 hours; end-capping reaction conditions are: end-capping reaction in a nitrogen atmosphere at a temperature of 50-60° C. for 1-2 hours; and neutralization conditions are: neutralization reaction at a temperature of 40-50° C. for 0.5-1 hour.

4. The method for preparing a high temperature resistant waterproof coating according to claim 1, characterized in that: In the step (1), the perfluoro chain extender is prepared by mixing 3-perfluoro-n-hexyl-1,2-propylene oxide and ethanolamine in a molar ratio of 2-2.5:1 and reacting them at a temperature of 105-115° C. for 8-9 hours.

5. The method for preparing a high temperature resistant waterproof coating according to claim 1, characterized in that: The hydroxy-terminated nitrile rubber / montmorillonite composite material in step (1) is prepared by the following steps: S11, mixing concentrated sulfuric acid and water evenly, adding montmorillonite, and performing activation treatment. After the treatment, filtering, washing, and drying are completed to obtain acidified montmorillonite; S12, mixing the acidified montmorillonite, ethanol and water, performing ultrasonic dispersion, and dropping 3-mercaptopropyltrimethoxysilane. After the dropping is complete, reacting, filtering, washing and drying after the reaction is complete to obtain mercapto-functionalized montmorillonite; S13, mixing and stirring the hydroxyl-terminated liquid nitrile rubber, mercapto-functionalized montmorillonite and dichloromethane evenly, adding a photoinitiator, reacting, and after the reaction, removing the solvent dichloromethane by rotary evaporation, washing, and drying to obtain a hydroxyl-terminated nitrile rubber / montmorillonite composite material.

6. The method for preparing a high temperature resistant waterproof coating according to claim 5, characterized in that: When preparing the hydroxy-terminated nitrile rubber / montmorillonite composite material, in S11: the mass ratio of concentrated sulfuric acid, water, and montmorillonite is 100:50-60:35-45, and the concentrated sulfuric acid is 98wt% concentrated sulfuric acid; the activation conditions are: stirring and activating at a temperature of 85-95°C for 3-4h; In S12, the mass ratio of acidified montmorillonite, ethanol, water, and 3-mercaptopropyltrimethoxysilane is 1:20-25:20-25:0.8-1; the reaction conditions are: stirring the reaction at room temperature for 6-8 hours; In S13, the mass ratio of hydroxyl-terminated liquid nitrile rubber, mercapto-functionalized montmorillonite, dichloromethane and photoinitiator is 10:4-5:40-50:0.4-0.5; the reaction conditions are: stirring the reaction at room temperature under an ultraviolet lamp environment with a wavelength of 365nm for 10-14h.

7. The method for preparing a high temperature resistant waterproof coating according to claim 1, characterized in that: In the step (2), the mass ratio of the first emulsion, the second emulsion, the initiator, the oxazolidinone acrylate, the γ-methacryloxypropyltrimethoxysilane, the hexafluorobutyl methacrylate and the styrene is 30-40:65-75:2-3:20-25:1-2:5-10:3-5.

8. The method for preparing a high temperature resistant waterproof coating according to claim 1, characterized in that: In the step (2), the reaction conditions are: reacting at a temperature of 60-70°C for 0.5-1h; adding the second portion of the emulsion for 1.5-2h; and continuing the reaction conditions are: continuing the reaction at a temperature of 65-75°C for 3-4h.

9. The method for preparing a high temperature resistant waterproof coating according to claim 1, characterized in that: The oxazolidinone acrylate in step (2) is prepared by the following steps: Neopentyl glycol diacrylate, 3-(2-hydroxyethyl)-2-oxazolidinone and potassium carbonate are mixed and reacted. After the reaction is completed, the temperature is lowered, the mixture is filtered, and the filtrate is collected and dried to obtain oxazolidinone acrylate; The mass ratio of neopentyl glycol diacrylate, 3-(2-hydroxyethyl)-2-oxazolidinone and potassium carbonate is 42-48:26-30:3.4-3.9; the reaction conditions are: reacting at a temperature of 45-55° C. for 16-18 hours.

10. A high temperature resistant waterproof coating prepared by the method for preparing a high temperature resistant waterproof coating as described in any one of claims 1 to 9.

Images