High-performance flexible explosion-proof coating based on nanofibers and preparation method of high-performance flexible explosion-proof coating

Abstract

The invention relates to the field of coatings, and provides a nanofiber-based high-performance flexible explosion-proof coating and a preparation method thereof.The nanofiber-based high-performance flexible explosion-proof coating is prepared from the following raw materials in parts by weight: 60-80 parts of polyurethane, 4-10 parts of composite nanofibers, 5-15 parts of modified carbon nanotubes, 1-5 parts of an adhesion promoter, 0.5-2 parts of a defoaming agent, 0.5-1.5 parts of a flatting agent and 0.5-2 parts of a dispersing agent. And 100 to 120 parts of a mixed solvent. The coating provided by the invention has the characteristics of good explosion-proof, heat-resistant and antistatic properties, and has better commercial application value.

Description

Technical Field

[0001] The invention relates to the field of coatings, and in particular to a high-performance flexible explosion-proof coating based on nanofibers and a preparation method thereof. Background Art

[0002] Explosion-proof coating is a special protective material, which is mainly used to prevent or reduce the damage to personnel and equipment caused by explosion shock waves and fragments. It can be widely used in flammable and explosive places such as petrochemical, coal mines, oil fields, and power equipment. In addition, explosion-proof coating can not only be used in industrial fields, but also in building materials such as homes and commercial places, which can provide comprehensive safety protection for people's production and life.

[0003] Polyurethane has high impact strength and good toughness and flexibility. It can be used as the main component of flexible explosion-proof coatings. However, polyurethane still has certain limitations when used alone as an explosion-proof coating. For example, polyurethane has limited heat resistance. It often faces high temperature environments in the explosion-proof field, and polyurethane may soften or deform at high temperatures, limiting its application in some extreme environments. In addition, polyurethane as a polymer itself does not have antistatic properties, and there may be hidden dangers of fire caused by static electricity.

[0004] Patent CN 114149730B discloses a flame-retardant and anti-fragmentation protective coating, a preparation method thereof and a coating prepared therefrom. The protective coating includes an A component composed of polyether polyol and isocyanate and a B component composed of amino-terminated polyether, amino-functionalized nano-carbon fiber, nano-ceramics, antistatic agent, etc., and has good anti-explosion and flame-retardant properties. However, the nano-ceramics are any one or more of aluminum oxide, silicon oxide, zirconium oxide, silicon carbide, boron carbide, tungsten carbide, silicon nitride and boron nitride, and have a problem of poor dispersibility, which makes it impossible to improve the impact resistance and wear resistance of the coating.

[0005] Therefore, there is an urgent need in the market for a high-performance flexible explosion-proof coating based on nanofibers with good explosion-proof, heat-resistant and antistatic properties. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention uses polyurethane as the main component of the coating, adds composite nanofibers, modified carbon nanotubes, adhesion promoters, defoaming agents, leveling agents, dispersants and mixed solvents to synthesize a high-performance flexible explosion-proof coating based on nanofibers, which has the characteristics of good explosion-proof, heat-resistant and antistatic properties.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] On the one hand, the present invention provides a high-performance flexible explosion-proof coating based on nanofibers. The coating comprises the following raw materials, measured by weight: 60-80 parts of polyurethane, 4-10 parts of composite nanofibers, 5-15 parts of modified carbon nanotubes, 1-5 parts of adhesion promoter, 0.5-2 parts of defoaming agent, 0.5-1.5 parts of leveling agent, 0.5-2 parts of dispersant, and 100-120 parts of mixed solvent.

[0009] In some embodiments of the present invention, the polyurethane is a mixture of an aromatic polyester polyurethane and an aromatic polyether polyurethane.

[0010] Preferably, the mass ratio of the aromatic polyester polyurethane to the aromatic polyether polyurethane is 1:(0.2-0.4).

[0011] Aromatic polyester polyurethane has the characteristics of high strength and high adhesion, and aromatic polyether polyurethane has good processing performance. The applicant mixes the two in a specific mass ratio to form a polyurethane main body, which can make the coating have excellent mechanical properties, adhesion and processing performance.

[0012] In some embodiments of the present invention, the method for preparing the composite nanofiber comprises the following steps:

[0013] Aluminum chloride and tin chloride are added to 1-hexadecyl-3-methylimidazole chloride, stirred, anhydrous ethanol is added, stirred, volatilized at 40-50°C for 47-49h, and then calcined at 500-600°C for 5-7h to obtain composite nanofibers.

[0014] In some embodiments of the present invention, the molar ratio of 1-hexadecyl-3-methylimidazolium chloride, aluminum chloride and tin chloride is 1:(0.4-0.6):(0.1-0.3).

[0015] Preferably, the molar ratio of 1-hexadecyl-3-methylimidazolium chloride, aluminum chloride and tin chloride is 1:0.5:0.2.

[0016] Polyurethane can be used as the main component of flexible explosion-proof coatings due to its excellent tensile strength, high impact strength and high toughness. However, polyurethane itself has limited heat resistance. In high temperature environments, polyurethane may soften or deform. In addition, polyurethane has certain flammability, so there are still certain application limitations in the field of explosion-proof coatings.

[0017] The applicant uses ionic liquid 1-hexadecyl-3-methylimidazolium chloride as a template, aluminum chloride as an aluminum source, and tin chloride as a tin source, and synthesizes composite nanofibers composed of aluminum oxide nanofibers and tin oxide nanofibers by a sol-gel method. On the one hand, the aluminum oxide nanofibers have good flame retardancy, high temperature resistance and impact resistance, which can effectively improve the explosion-proof performance of the coating, while the tin oxide nanofibers have high conductivity, weather resistance and stability, which can further improve the durability and antistatic properties of the coating; on the other hand, the sol-gel method selected by the applicant has mild reaction conditions and a simple synthesis process, and the applicant controls the reaction ratio between 1-hexadecyl-3-methylimidazolium chloride and aluminum chloride and tin chloride so that the hydrogen bonds and association effects formed by the anionic structure obtained by the reaction and the hydrogen atoms in the imidazole ring are stronger, thereby making the prepared composite nanofibers more orderly stacked and having good thermal stability and good dispersibility, thereby effectively improving the explosion-proof performance of the coating.

[0018] In some embodiments of the present invention, the method for preparing the modified carbon nanotubes comprises the following steps:

[0019] 1) adding single-walled carbon nanotubes to an aqueous hydrogen peroxide solution, ultrasonicating, adding an aqueous sulfuric acid solution, refluxing at 100-110° C. for 50-70 min, filtering, washing until the filtrate is neutral, transferring the solid on the filter membrane to deionized water, ultrasonicating, centrifuging, washing, and drying to obtain carboxylated carbon nanotubes for use;

[0020] 2) taking the carboxylated carbon nanotubes from step 1) and adding them into deionized water, adding aniline and itaconic acid, stirring, adding sodium dodecyl diphenyl ether disulfonate and sodium polynaphthaldehyde sulfonate, sonicating, adding sulfuric acid aqueous solution to adjust the pH to 1-2, sonicating, cooling to 0-4° C., and obtaining an intermediate product for use;

[0021] 3) adding ammonium persulfate to a sulfuric acid aqueous solution, stirring, and then adding to the intermediate product of step 2), stirring, centrifuging, washing, and drying to obtain modified carbon nanotubes.

[0022] Wherein, in the step 2), the mass ratio of carboxylated carbon nanotubes, sodium dodecyl diphenyl oxide disulfonate and sodium polynaphthaldehyde sulfonate is 1:(0.7-0.9):(0.2-0.4).

[0023] In some embodiments of the present invention, in step 1), the mass ratio of the single-walled carbon nanotubes to the hydrogen peroxide in the aqueous hydrogen peroxide solution is 1:(38-42).

[0024] Preferably, in step 1), the mass ratio of the single-walled carbon nanotubes to the hydrogen peroxide in the aqueous hydrogen peroxide solution is 1:40.

[0025] In some embodiments of the present invention, in step 2), the mass ratio of carboxylated carbon nanotubes, aniline and itaconic acid is 1:(7.5-8.5):(9-11).

[0026] Preferably, in step 2), the mass ratio of carboxylated carbon nanotubes, aniline and itaconic acid is 1:8:10.

[0027] In addition to high impact strength, good toughness, and high temperature resistance, explosion-proof coatings also need to have good antistatic properties in certain flammable and explosive environments to reduce the risk of fire caused by static electricity. The antistatic properties of polyurethane itself are limited, while carbon nanotubes are a material with excellent electrical conductivity and a very low surface charge density, which can effectively prevent static electricity accumulation. However, the huge aspect ratio of carbon nanotubes and the van der Waals force between the tube bundles make the carbon nanotubes have a strong attraction, which makes them prone to agglomeration, and thus their antistatic properties cannot be well exerted in the coating.

[0028] The applicant firstly adopts hydrogen peroxide oxidation method to prepare carboxylated carbon nanotubes. Compared with the mixed acid acidification method to prepare carboxylated carbon nanotubes, this method is safer, more environmentally friendly, and the reaction process is more gentle; further, the applicant adopts itaconic acid as a dopant, ammonium persulfate as an initiator, and introduces aniline to modify the carboxylated carbon nanotubes. On the one hand, the applicant obtains a composite material of carboxylated carbon nanotubes and polyaniline by controlling the ratio of aniline monomer and carboxylated carbon nanotubes, which effectively improves the heat resistance and antistatic properties of the carbon nanotubes, and there is a certain π-π conjugation and hydrogen bonding between polyaniline and carboxylated carbon nanotubes, which can further improve the heat resistance and stability of the modified carbon nanotubes; on the other hand, the applicant selects itaconic acid as a dopant, and selects sodium dodecyl diphenyl ether disulfonate and sodium polynaphthaldehyde sulfonate as surfactants to act synergistically, so that polyaniline is evenly coated on the surface of the carboxylated carbon nanotubes and the obtained modified carbon nanotube particles are uniform, thereby effectively improving the dispersibility of the modified carbon nanotubes.

[0029] In some embodiments of the present invention, the adhesion promoter is aminophenyltrimethoxysilane or 3-(phenylamino)propyltrimethoxysilane.

[0030] In some embodiments of the present invention, the mixed solvent is a mixture of dimethylformamide and butyl acetate.

[0031] Preferably, the mass ratio of dimethylformamide to butyl acetate is 1:(0.15-0.35).

[0032] Another aspect of the present invention further provides a method for preparing the high-performance flexible explosion-proof coating based on nanofibers as described in the above technical solution, comprising the following steps:

[0033] S1, adding polyurethane, composite nanofibers, modified carbon nanotubes, adhesion promoter, defoamer, leveling agent and dispersant into a mixed solvent, raising the temperature to 60-80° C. while stirring, and continuing to stir to obtain a coating for use;

[0034] S2, coating the coating of step S1 on the tinplate sheet and curing it to obtain a high-performance flexible explosion-proof coating based on nanofibers.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] (1) The present invention uses polyurethane as the main component of the coating, and adds composite nanofibers, modified carbon nanotubes, adhesion promoters, defoaming agents, leveling agents, dispersants and mixed solvents to synthesize a high-performance flexible explosion-proof coating based on nanofibers. Through the synergistic effect of the various components, the high-performance flexible explosion-proof coating based on nanofibers has the characteristics of good explosion-proof, heat-resistant and antistatic properties.

[0037] (2) The present invention uses ionic liquid 1-hexadecyl-3-methylimidazolium chloride as a template, aluminum chloride as an aluminum source, and tin chloride as a tin source, and synthesizes composite nanofibers composed of aluminum oxide nanofibers and tin oxide nanofibers through a sol-gel method. The composite nanofibers have good heat resistance, flame retardancy, impact resistance and dispersibility, thereby effectively improving the explosion-proof performance of the coating.

[0038] (3) The present invention first adopts hydrogen peroxide oxidation method to prepare carboxylated carbon nanotubes, then adopts itaconic acid as a dopant, ammonium persulfate as an initiator, and introduces aniline to modify the carboxylated carbon nanotubes, and selects sodium dodecyl diphenyl ether disulfonate and sodium polynaphthaldehyde sulfonate as surfactants to synergistically improve the antistatic property and dispersibility of the carbon nanotubes, thereby making the coating have good antistatic property.

[0039] (4) The coating prepared by the present invention has the characteristics of good explosion-proof, heat-resistant and antistatic properties, can be widely used in the field of flexible explosion-proof coatings, and has good commercial application value. DETAILED DESCRIPTION

[0040] The present invention will be described below in conjunction with specific embodiments. It should be noted that the following embodiments are examples of the present invention and are only used to illustrate the present invention, but not to limit the present invention. Other combinations and various modifications within the concept of the present invention may be performed without departing from the spirit or scope of the present invention.

[0041] In the following embodiments and comparative examples, except for the composite nanofibers and modified carbon nanotubes, the other compound monomers and related reagents used can be purchased from the market. Among them, the aromatic polyester polyurethane was purchased from Dongguan Jiurui Plastic Raw Materials Co., Ltd.; the aromatic polyether polyurethane was purchased from Dongguan Zhangmutou Hongyun Plastic Raw Materials Business Department; the sodium salt of polynaphthalene formaldehyde sulfonate was purchased from Jining Changsheng New Materials Co., Ltd.; the defoaming agent was defoaming agent BYK-1711, purchased from Guangzhou Si Tuyuan Chemical Co., Ltd.; the leveling agent was leveling agent PV88, purchased from Foshan Jie Ke New Materials Co., Ltd.; the dispersant was BASF Disponil A 1080, purchased from Shanghai Zhenli Shi Network Technology Co., Ltd.

[0042] Preparation Example 1

[0043] The synthesis method of composite nanofiber A comprises the following steps:

[0044] 0.05 mol aluminum chloride and 0.02 mol tin chloride were added to 0.1 mol 1-hexadecyl-3-methylimidazolium chloride, stirred for 1.5 h, 40 ml anhydrous ethanol was added, stirred for 30 min, evaporated at 45° C. for 48 h, and then calcined at 550° C. for 6 h to obtain composite nanofiber A.

[0045] Preparation Example 2

[0046] The specific implementation of composite nanofiber B is the same as that of composite nanofiber A, except that the molar number of aluminum chloride is replaced with 0.03 mol.

[0047] Preparation Example 3

[0048] The specific implementation manner of composite nanofiber C is the same as that of composite nanofiber A, except that the molar number of tin chloride is replaced by 0.008 mol.

[0049] Preparation Example 4

[0050] The synthesis method of modified carbon nanotube A comprises the following steps:

[0051] 1) 1.5 g of single-walled carbon nanotubes were added to 200 ml of 30 wt% hydrogen peroxide aqueous solution, ultrasonicated for 60 min, 40 ml of 0.6 mol / L sulfuric acid aqueous solution was added, refluxed at 105° C. for 60 min, filtered with a 0.45 μm microporous filter membrane, washed with deionized water until the filtrate was neutral, and then the solid on the filter membrane was transferred to 100 ml of deionized water, ultrasonicated for 30 min, centrifuged, washed with deionized water 3 times, and dried at 50° C. to constant weight to obtain carboxylated carbon nanotubes for use;

[0052] 2) Take 1.5g of the carboxylated carbon nanotubes prepared in step 1) and add them to 300ml of deionized water, add 12g of aniline and 15g of itaconic acid, stir for 1h, add 1.2g of sodium dodecyl diphenyl ether disulfonate and 0.5g of sodium polynaphthaldehyde sulfonate, sonicate for 30min, add 30wt% aqueous sulfuric acid solution to adjust the pH to 1.5, sonicate for 30min, cool to 0°C, and obtain an intermediate product for use;

[0053] 3) 30 g of ammonium persulfate and 150 ml of 0.05 mol / L sulfuric acid solution were added, stirred for 30 min, and then added to the intermediate product of step 2), stirred for 6 h, centrifuged, washed with deionized water until pH = 7, and vacuum dried at 60°C for 12 h to obtain modified carbon nanotubes A.

[0054] Preparation Example 5

[0055] The specific implementation method of modified carbon nanotube B is the same as that of modified carbon nanotube A, except that in step 1), the volume of the hydrogen peroxide aqueous solution is replaced with 185 ml.

[0056] Preparation Example 6

[0057] The specific implementation manner of modified carbon nanotube C is the same as that of modified carbon nanotube A, except that in step 2), the mass of aniline is replaced with 10.6 g.

[0058] Preparation Example 7

[0059] The specific implementation method of modified carbon nanotube D is the same as that of modified carbon nanotube A, except that in step 2), the mass of itaconic acid is replaced with 13 g.

[0060] Example 1

[0061] A high-performance flexible explosion-proof coating based on nanofibers. The coating comprises the following raw materials, measured by weight: 70 parts of polyurethane, 7 parts of composite nanofiber A, 10 parts of modified carbon nanotube A, 3 parts of aminophenyltrimethoxysilane, 1.25 parts of defoamer BYK-1711, 1 part of leveling agent PV88, 1.25 parts of dispersant BASF Disponil A 1080, and 110 parts of mixed solvent.

[0062] The polyurethane is a mixture of aromatic polyester polyurethane and aromatic polyether polyurethane, with a mass ratio of 1:0.3.

[0063] The mixed solvent is a mixture of dimethylformamide and butyl acetate, with a mass ratio of 1:0.25.

[0064] The preparation method of the high-performance flexible explosion-proof coating based on nanofibers in this embodiment includes the following steps:

[0065] S1, adding polyurethane, composite nanofiber A, modified carbon nanotube A, aminophenyltrimethoxysilane, defoamer BYK-1711, leveling agent PV88 and dispersant BASF Disponil A 1080 into a mixed solvent, heating to 70° C. while stirring, and continuing stirring for 2 h to obtain a coating for standby use;

[0066] S2. Apply the coating of step S1 on a tinplate sheet with a thickness of 20 μm and cure at 60° C. for 12 h to obtain a high-performance flexible explosion-proof coating based on nanofibers.

[0067] Example 2

[0068] A high-performance flexible explosion-proof coating based on nanofibers. The coating comprises the following raw materials, measured by weight: 60 parts of polyurethane, 7 parts of composite nanofiber A, 5 parts of modified carbon nanotube A, 1 part of 3-(phenylamino)propyltrimethoxysilane, 0.5 parts of defoamer BYK-1711, 0.5 parts of leveling agent PV88, 0.5 parts of dispersant BASF Disponil A 1080, and 100 parts of mixed solvent.

[0069] The polyurethane is a mixture of aromatic polyester polyurethane and aromatic polyether polyurethane, with a mass ratio of 1:0.2.

[0070] The mixed solvent is a mixture of dimethylformamide and butyl acetate, with a mass ratio of 1:0.15.

[0071] The preparation method of the high-performance flexible explosion-proof coating based on nanofibers in this embodiment includes the following steps:

[0072] S1, adding polyurethane, composite nanofiber A, modified carbon nanotube A, 3-(phenylamino)propyltrimethoxysilane, defoamer BYK-1711, leveling agent PV88 and dispersant BASF Disponil A 1080 into a mixed solvent, heating to 60° C. while stirring, and continuing stirring for 2 h to obtain a coating for standby use;

[0073] S2. Apply the coating of step S1 on a tinplate sheet with a thickness of 20 μm and cure at 60° C. for 12 h to obtain a high-performance flexible explosion-proof coating based on nanofibers.

[0074] Example 3

[0075] A high-performance flexible explosion-proof coating based on nanofibers. The coating comprises the following raw materials, measured by weight: 80 parts of polyurethane, 7 parts of composite nanofiber A, 15 parts of modified carbon nanotube A, 5 parts of aminophenyltrimethoxysilane, 2 parts of defoamer BYK-1711, 1.5 parts of leveling agent PV88, 2 parts of dispersant BASF Disponil A 1080, and 120 parts of mixed solvent.

[0076] The polyurethane is a mixture of aromatic polyester polyurethane and aromatic polyether polyurethane, with a mass ratio of 1:0.4.

[0077] The mixed solvent is a mixture of dimethylformamide and butyl acetate, with a mass ratio of 1:0.35.

[0078] The preparation method of the high-performance flexible explosion-proof coating based on nanofibers in this embodiment includes the following steps:

[0079] S1, adding polyurethane, composite nanofiber A, modified carbon nanotube A, aminophenyltrimethoxysilane, defoamer BYK-1711, leveling agent PV88 and dispersant BASF Disponil A 1080 into a mixed solvent, heating to 80° C. while stirring, and continuing stirring for 2 h to obtain a coating for standby use;

[0080] S2. Apply the coating of step S1 on a tinplate sheet with a thickness of 20 μm and cure at 60° C. for 12 h to obtain a high-performance flexible explosion-proof coating based on nanofibers.

[0081] Example 4

[0082] A high-performance flexible explosion-proof coating based on nanofibers. The coating comprises the following raw materials, measured by weight: 65 parts of polyurethane, 4 parts of composite nanofiber A, 10 parts of modified carbon nanotube A, 2 parts of aminophenyltrimethoxysilane, 1 part of defoamer BYK-1711, 0.7 parts of leveling agent PV88, 1 part of dispersant BASF Disponil A 1080, and 105 parts of mixed solvent.

[0083] The polyurethane and the mixed solvent are the same as those in Example 1.

[0084] The preparation method of the high-performance flexible explosion-proof coating based on nanofibers in this embodiment is the same as that in Example 1.

[0085] Example 5

[0086] A high-performance flexible explosion-proof coating based on nanofibers. The coating comprises the following raw materials, measured by weight: 75 parts of polyurethane, 10 parts of composite nanofiber A, 10 parts of modified carbon nanotube A, 4 parts of 3-(phenylamino)propyltrimethoxysilane, 1.5 parts of defoamer BYK-1711, 1.2 parts of leveling agent PV88, 1.5 parts of dispersant BASF Disponil A 1080, and 115 parts of mixed solvent.

[0087] The polyurethane and the mixed solvent are the same as those in Example 1.

[0088] The preparation method of the high-performance flexible explosion-proof coating based on nanofibers in this embodiment is the same as that in Example 1.

[0089] Example 6

[0090] This embodiment provides a high-performance flexible explosion-proof coating based on nanofibers and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the composite nanofibers B replace the composite nanofibers A in equal amounts.

[0091] Example 7

[0092] This embodiment provides a high-performance flexible explosion-proof coating based on nanofibers and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the composite nanofibers C replace the composite nanofibers A in equal amounts.

[0093] Example 8

[0094] This embodiment provides a high-performance flexible explosion-proof coating based on nanofibers and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified carbon nanotubes B replace the modified carbon nanotubes A in equal amounts.

[0095] Example 9

[0096] This embodiment provides a high-performance flexible explosion-proof coating based on nanofibers and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified carbon nanotubes A are replaced by modified carbon nanotubes C in equal amounts.

[0097] Example 10

[0098] This embodiment provides a high-performance flexible explosion-proof coating based on nanofibers and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified carbon nanotubes A are replaced by modified carbon nanotubes D in equal amounts.

[0099] Comparative Example 1

[0100] This comparative example provides a high-performance flexible explosion-proof coating based on nanofibers and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the composite nanofiber A is replaced by alumina nanofibers.

[0101] The synthesis method of aluminum oxide nanofibers comprises the following steps:

[0102] 0.05 mol of aluminum chloride was added to 0.1 mol of 1-hexadecyl-3-methylimidazolium chloride, stirred for 1.5 hours, 40 ml of anhydrous ethanol was added, stirred for 30 minutes, evaporated at 45°C for 48 hours, and then calcined at 550°C for 6 hours to obtain aluminum oxide nanofibers.

[0103] Comparative Example 2

[0104] This comparative example provides a high-performance flexible explosion-proof coating based on nanofibers and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that the composite nanofiber A is replaced by tin oxide nanofibers.

[0105] The synthesis method of tin oxide nanofibers comprises the following steps:

[0106] 0.02 mol of tin chloride was added to 0.1 mol of 1-hexadecyl-3-methylimidazolium chloride, stirred for 1.5 h, 40 ml of anhydrous ethanol was added, stirred for 30 min, evaporated at 45° C. for 48 h, and then calcined at 550° C. for 6 h to obtain tin oxide nanofibers.

[0107] Comparative Example 3

[0108] This comparative example provides a high-performance flexible explosion-proof coating based on nanofibers and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that single-walled carbon nanotubes are used to replace the modified carbon nanotubes A in equal amounts.

[0109] The synthesis method of single-walled carbon nanotubes is the same as that of Preparation Example 4.

[0110] Performance Testing

[0111] The explosion-proof, heat-resistant and antistatic properties of the high-performance flexible explosion-proof coatings based on nanofibers of the above Examples 1-10 and Comparative Examples 1-3 were tested, and the test results are shown in Table 1.

[0112] (1) Explosion-proof and heat-resistant performance

[0113] In order to simultaneously test the explosion-proof and heat-resistant properties of the coatings, the explosion-proof properties of the coatings obtained in the examples and comparative examples were tested at 200°C.

[0114] 1) Tensile strength

[0115] Reference standard GB / T 528-2009.

[0116] 2) Tear strength

[0117] Reference standard GB / T 528-2008.

[0118] 3) Impact strength

[0119] Reference standard GB / T 20624.2-2006.

[0120] (2) Antistatic properties

[0121] Test the surface resistivity of the coating. The smaller the surface resistivity, the better the antistatic performance. Refer to standard ASTM D 257.

[0122] Table 1

[0123]

[0124]

[0125] It can be seen from the data in Table 1 that the high-performance flexible explosion-proof coating based on nanofibers in Examples 1-5 of the present invention has good explosion-proof, heat-resistant and antistatic properties as a whole. Among them, Examples 6-7 change the addition ratio of aluminum oxide and tin oxide in the synthesis process of composite nanofibers, so that the heat resistance and explosion-proof performance of the composite nanofibers are not well improved, which leads to a significant decrease in the tensile strength, tear strength and impact strength of the coating, but has little effect on the antistatic performance of the coating; Examples 8-10 change the addition ratio of the main components in the modified carbon nanotubes, so that the dispersibility of the modified carbon nanotubes decreases, which leads to a significant decrease in the antistatic property of the coating, and the explosion-proof performance also decreases accordingly; Comparative Examples 1-3 respectively use aluminum oxide nanofibers and tin oxide nanofibers to replace composite nanofibers A in equal amounts and single-walled carbon nanotubes to replace modified carbon nanotubes A in equal amounts. Tests show that the explosion-proof, heat-resistant and antistatic properties of the high-performance flexible explosion-proof coating based on nanofibers all show poor results.

[0126] The above implementation modes are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-performance flexible explosion-proof coating based on nanofibers, characterized in that: The coating comprises the following raw materials by weight: 60-80 parts of polyurethane, 4-10 parts of composite nanofibers, 5-15 parts of modified carbon nanotubes, 1-5 parts of adhesion promoter, 0.5-2 parts of defoamer, 0.5-1.5 parts of leveling agent, 0.5-2 parts of dispersant and 100-120 parts of mixed solvent.

2. The high-performance flexible explosion-proof coating based on nanofibers according to claim 1, characterized in that: The polyurethane is a mixture of aromatic polyester polyurethane and aromatic polyether polyurethane.

3. The high-performance flexible explosion-proof coating based on nanofibers according to claim 1, characterized in that: The preparation method of the composite nanofiber comprises the following steps: Aluminum chloride and tin chloride are added to 1-hexadecyl-3-methylimidazole chloride, stirred, anhydrous ethanol is added, stirred, volatilized at 40-50°C for 47-49h, and then calcined at 500-600°C for 5-7h to obtain composite nanofibers.

4. The high-performance flexible explosion-proof coating based on nanofibers according to claim 3 is characterized in that: The molar ratio of 1-hexadecyl-3-methylimidazolium chloride, aluminum chloride and tin chloride is 1:(0.4-0.6):(0.1-0.3).

5. The high-performance flexible explosion-proof coating based on nanofibers according to claim 1, characterized in that: The preparation method of the modified carbon nanotubes comprises the following steps: 1) adding single-walled carbon nanotubes to an aqueous hydrogen peroxide solution, ultrasonicating, adding an aqueous sulfuric acid solution, refluxing at 100-110° C. for 50-70 min, filtering, washing until the filtrate is neutral, transferring the solid on the filter membrane to deionized water, ultrasonicating, centrifuging, washing, and drying to obtain carboxylated carbon nanotubes for use; 2) taking the carboxylated carbon nanotubes from step 1) and adding them into deionized water, adding aniline and itaconic acid, stirring, adding sodium dodecyl diphenyl ether disulfonate and sodium polynaphthaldehyde sulfonate, sonicating, adding sulfuric acid aqueous solution to adjust the pH to 1-2, sonicating, cooling to 0-4° C., and obtaining an intermediate product for use; 3) adding ammonium persulfate to a sulfuric acid aqueous solution, stirring, and then adding to the intermediate product of step 2), stirring, centrifuging, washing, and drying to obtain modified carbon nanotubes.

6. The high-performance flexible explosion-proof coating based on nanofibers according to claim 5, characterized in that: In the step 1), the mass ratio of the single-walled carbon nanotubes to the hydrogen peroxide in the hydrogen peroxide aqueous solution is 1:(38-42).

7. The high-performance flexible explosion-proof coating based on nanofibers according to claim 5, characterized in that: In the step 2), the mass ratio of carboxylated carbon nanotubes, aniline and itaconic acid is 1:(7.5-8.5):(9-11).

8. The high-performance flexible explosion-proof coating based on nanofibers according to claim 1, characterized in that: The adhesion promoter is aminophenyltrimethoxysilane or 3-(phenylamino)propyltrimethoxysilane.

9. The high-performance flexible explosion-proof coating based on nanofibers according to claim 1, characterized in that: The mixed solvent is a mixture of dimethylformamide and butyl acetate.

10. A method for preparing a high-performance flexible explosion-proof coating based on nanofibers according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, adding polyurethane, composite nanofibers, modified carbon nanotubes, adhesion promoter, defoamer, leveling agent and dispersant into a mixed solvent, raising the temperature to 60-80° C. while stirring, and continuing to stir to obtain a coating for use; S2, coating the coating of step S1 on the tinplate sheet and curing it to obtain a high-performance flexible explosion-proof coating based on nanofibers.

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