High-temperature-resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy

Abstract

The application relates to the technical field of metal surface treatment, and relates to a high-temperature-resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy, which comprises the following raw materials in parts by weight: 20-25 parts of acrylic acid modified epoxy resin, 8-10 parts of gamma-aminopropyl triethoxysilane, 4-6 parts of modified filler, 4-6 parts of modified silane, 1-2 parts of curing agent, 60-70 parts of ethanol and 20-25 parts of water; the modified filler and the modified silane are added in the film forming agent, so that the film layer formed on the surface of the high-aluminum alloy after the high-temperature-resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy is used has good high-temperature-resistant anti-oxidation performance; when the film layer encounters high temperature, the benzocyclobutene groups in the modified silane will have self-crosslinking polymerization behavior, so that the film layer has good high-temperature resistance; when the film layer is damaged, the modified filler can produce self-repairing behavior, so that the film layer has certain self-repairing ability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metal surface treatment, in particular, relates to a kind of high-temperature oxidation-resistant film forming agent for hot-dip galvanizing high-aluminum alloy. BACKGROUND

[0002] Due to the advantages of light weight, high strength, corrosion resistance and the like, aluminum alloy has been widely used in the fields of aircraft manufacturing, automobile parts manufacturing and the like. In recent years, the automobile industry has put forward more stringent requirements on the performance of aluminum alloy. Not only is it required to have higher and more durable atmospheric corrosion resistance, but also is required to have the ability to resist oxidation at a higher temperature and better coating performance. Therefore, a film forming agent is usually selected to be used to treat the surface of hot-dip galvanizing high-aluminum alloy, so as to make it have good corrosion resistance and oxidation resistance.

[0003] After the film forming agent is formed on the surface of hot-dip galvanizing high-aluminum alloy, it only plays a physical blocking role to the corrosion medium in the protection process and does not have self-repairing ability. Once the film layer is mechanically damaged, the corrosion medium will quickly penetrate into the substrate and cause corrosion. Therefore, after the film layer is damaged, the hot-dip galvanizing high-aluminum alloy will be quickly oxidized and corroded. At the same time, most of the film forming agents will have performance degradation, even thermal decomposition and peeling phenomenon under high temperature conditions. SUMMARY

[0004] The present application provides a kind of high-temperature oxidation-resistant film forming agent for hot-dip galvanizing high-aluminum alloy, solve the problems of existing hot-dip galvanizing high-aluminum alloy oxidation-resistant film forming agent without self-repairing ability and poor high-temperature resistance.

[0005] The object of the present application can be achieved by the following technical solutions:

[0006] A kind of high-temperature oxidation-resistant film forming agent for hot-dip galvanizing high-aluminum alloy is prepared by the following steps: step S1: the following weight parts of raw materials are weighed: 20-25 parts of acrylic acid modified epoxy resin, 8-10 parts of γ-aminopropyl triethoxysilane, 4-6 parts of modified filler, 4-6 parts of modified silane, 1-2 parts of curing agent, 60-70 parts of ethanol and 20-25 parts of water;

[0007] Step S2: mix the acrylic acid modified epoxy resin, ethanol and water, add γ-aminopropyl triethoxysilane, modified silane and modified filler, stir for 30-40 min, then add the curing agent and continue to stir for 5-10 min, to prepare a kind of high-temperature oxidation-resistant film forming agent for hot-dip galvanizing high-aluminum alloy;

[0008] The modified filler is prepared by the following steps:

[0009] Step A1: mixing silica, anhydrous ethanol, acetonitrile and ammonia water and ultrasonic dispersion for 30 min to prepare a silica suspension, slowly dropping zirconium n-propyl alcohol solution into the silica suspension at a stirring rate of 700-800 rpm and room temperature, and reacting for 6-8 h to prepare mesoporous zirconia, mixing the mesoporous zirconia and deionized water, stirring at a stirring rate of 300-400 rpm and a temperature of 80℃, and adding sodium hydroxide solution to prepare hollow mesoporous zirconia;

[0010] The mass fraction of ammonia water is 25%, the dosage ratio of silica and ammonia water is 3-4 g:2-3 mL, the mass fraction of zirconium n-propyl alcohol solution is 70%, the dosage ratio of zirconium n-propyl alcohol solution and silica suspension is 15-20 mL:150 mL, the molar concentration of sodium hydroxide solution is 1 mol / L, and the dosage ratio of mesoporous zirconia and sodium hydroxide solution is 4-5 g:18-20 mL;

[0011] During the reaction, by dropping zirconium n-propyl alcohol solution into the silica suspension, zirconium n-propyl alcohol is hydrolyzed and reacts with ammonia water to form zirconia wrapped silica to prepare mesoporous zirconia, which is then added to sodium hydroxide solution, and the silica in the center of the mesoporous zirconia is etched to prepare hollow mesoporous zirconia;

[0012] Step A2: mixing hollow mesoporous zirconia, 2-mercaptobenzothiazole and anhydrous ethanol, ultrasonic dispersion for 20-25 min, vacuum degree below 2.02 kPa and room temperature, reaction for 9-12 h, filtration, drying to prepare a loaded mesoporous material, mixing the loaded mesoporous material with cerium nitrate solution, stirring at a stirring rate of 200-300 rpm and room temperature for 3-5 min, suction filtration and washing to prepare a precursor;

[0013] The dosage ratio of hollow mesoporous zirconia, 2-mercaptobenzothiazole and anhydrous ethanol is 3-4 g:8-10 g:100 mL, the molar concentration of cerium nitrate solution is 0.01 mol / L, and the dosage ratio of loaded mesoporous material and cerium nitrate solution is 4-5 g:80-100 mL;

[0014] During the reaction, 2-mercaptobenzothiazole enters and is loaded in the hollow mesoporous zirconia by vacuum impregnation to prepare a loaded mesoporous material, and then the loaded mesoporous material is added to the cerium nitrate solution, and through the complexation of cerium ions and 2-mercaptobenzothiazole, a plug is formed at the port of the hollow mesoporous zirconia to encapsulate 2-mercaptobenzothiazole in the mesoporous material to prepare a precursor;

[0015] Step A3: the double-[3-(triethoxysilane)propyl]-disulfide and ethanol solution were mixed, the precursor was stirred and added at a stirring rate of 800-1000 rpm and a temperature of 50°C, reacted for 30 min, and then reacted for 2 h under the protection of nitrogen, 100 W ultraviolet light irradiation, a stirring rate of 120-180 rpm, and a temperature of 80°C to obtain a grafted precursor; the phytic acid and propylene glycol methyl ether were mixed, the glycidyl methacrylate and tetrabutylammonium bromide were stirred and added under 100 W ultraviolet light irradiation, a stirring rate of 600-700 rpm, and a temperature of 90°C, reacted for 1.5-2 h, and then the grafted precursor was added and reacted for 3-4 h to obtain a modified filler;

[0016] The mass fraction of the ethanol solution was 90%, and the amount ratio of the double-[3-(triethoxysilane)propyl]-disulfide to the precursor was 2-3 mL:2 g; the amount ratio of the phytic acid, the grafted precursor, and the tetrabutylammonium bromide was 1-2 g:2 g:0.05 g;

[0017] During the reaction, the ethoxyl groups in the double-[3-(triethoxysilane)propyl]-disulfide were first hydrolyzed to hydroxyl groups in the ethanol solution, which were then combined with the surface of the precursor; then the temperature was increased and the disulfide bond was broken to form a mercapto group under ultraviolet irradiation to obtain a grafted precursor containing a mercapto group; the phosphate groups in the phytic acid reacted with the epoxy groups in the glycidyl methacrylate to introduce a double bond; and then the grafted precursor was added and the mercapto group in the grafted precursor reacted with the double bond to obtain a modified filler;

[0018] The modified silane was prepared by the following steps:

[0019] Step B1: 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, 4-boronic acid base benzocyclobutene, potassium phosphate tribasic, ethanol, and deionized water were mixed, tetrakis(triphenylphosphine)palladium was added under the protection of nitrogen, a stirring rate of 200-300 rpm, and a temperature of 60°C, and reacted for 8-10 h to obtain an intermediate 1;

[0020] The amount ratio of 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, 4-boronic acid base benzocyclobutene, potassium phosphate tribasic, and tetrakis(triphenylphosphine)palladium was 0.1 mol:0.12-0.14 mol:0.2 mol:0.1 mol;

[0021] During the reaction, the bromo groups in the 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride underwent Suzuki-Miyaura reaction with the boronic acid groups in the 4-boronic acid base benzocyclobutene under the action of tetrakis(triphenylphosphine)palladium and potassium phosphate tribasic to obtain an intermediate 1 containing a benzocyclobutene group;

[0022] Step B2: Intermediate 1 and acetic acid were mixed, stirred at a stirring rate of 200-300 rpm and a temperature of 120 °C, and 3-buten-1-amine was added and reacted for 6-8 h to produce intermediate 2;

[0023] The amount ratio of intermediate 1 and 3-buten-1-amine was 0.1 mol: 0.2-0.22 mol;

[0024] During the reaction, the acid anhydride group in intermediate 1 reacted with the amino group in 3-buten-1-amine to form an imide group to produce intermediate 2;

[0025] Step B3: Intermediate 2 and toluene were mixed, stirred at a stirring rate of 200-300 rpm and a temperature of 70 °C under nitrogen protection, and triethoxysilane and Karstedt catalyst were added and reacted for 24 h to produce modified silane;

[0026] The amount ratio of intermediate 2, triethoxysilane and Karstedt catalyst was 0.1 mol: 0.2-0.22 mol: 1-2 mL;

[0027] During the reaction, the double bond in intermediate 2 underwent a silicon-hydrogen addition reaction with triethoxysilane to produce modified silane containing silane grafting;

[0028] The application discloses a high-temperature-resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy, and has the advantages that the high-temperature-resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy has good high-temperature-resistant anti-oxidation performance after film forming on the surface of the aluminum alloy, and when the film layer is damaged, the modified filler can produce a self-repairing behavior due to the presence of the modified filler, so that the film layer has a certain self-repairing ability; the modified filler is prepared by loading 2-mercaptobenzothiazole in hollow mesoporous zirconium oxide, sealing the pores by complexing cerium ions with 2-mercaptobenzothiazole, and introducing phytic acid on the surface of the modified filler by silane; the modified filler is added into the film forming agent, the phytic acid groups are grafted on the outside of the modified filler, the presence of the phytic acid not only improves the dispersion performance of the modified filler in the film forming agent, but also enables the phosphate groups in the phytic acid to participate in the polymerization process between silanes, so that the modified filler is better combined with the film layer; the modified filler itself is a hollow mesoporous zirconium oxide material, which can extend the dispersion path of corrosive oxidizing substances when the film layer is corroded and oxidized from the outside, thereby slowing down the corrosion and oxidation; the modified filler can also play the role of the filler itself, that is, improve the heat resistance of the film layer; the complex form of cerium ions and 2-mercaptobenzothiazole can be decomposed and react with oxidizing substances under acidic or alkaline conditions, thereby generating cerium-containing oxides, which can protect the hot-dip galvanizing high-aluminum alloy, thereby slowing down the oxidation rate of the hot-dip galvanizing high-aluminum alloy after the film layer is damaged; after the complex is decomposed, the 2-mercaptobenzothiazole in the modified filler is released, which can be complexed with metal ions on the surface of the hot-dip galvanizing high-aluminum alloy, thereby forming a new protective film layer to protect the hot-dip galvanizing high-aluminum alloy again; the modified silane is prepared by using 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride as a base, reacting with 4-boronic acid-based benzocyclobutene to obtain an intermediate 1, reacting the intermediate 1 with 3-buten-1-amine to obtain an intermediate 2, and then reacting the intermediate 2 with triethoxysilane through hydrosilylation to obtain the modified silane; the perylene structure exists in the modified silane, which is a rigid macromolecular structure, and plays a role of a connecting point when silanes in the film forming agent are hydrolyzed and condensed, thereby improving the heat resistance of the film layer; and the benzocyclobutene group exists in the modified silane, and the four-membered ring in the benzocyclobutene group is opened to generate an o-dimethyl enedione intermediate under high-temperature conditions, the o-dimethyl enedione intermediates can be self-polymerized to form a diphenyl cyclooctadiene, and then a polymer is formed through a double free radical mechanism through rearrangement; the self-polymerization of the modified silane under high-temperature conditions can effectively enhance the high-temperature resistance of the film layer under high-temperature conditions, so that the film layer will not be decomposed or fall off under high-temperature conditions. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0030] Embodiment 1

[0031] The modified filler is prepared by the following steps:

[0032] Step A1: commercially available Cabot 80 nm silica, anhydrous ethanol, acetonitrile and ammonia water are mixed and ultrasonically dispersed for 30 min to prepare a silica suspension; under the condition of a stirring rate of 700 rpm and room temperature, a zirconium n-propyl alcohol solution is slowly dropped into the silica suspension, and reacted for 6 h to prepare mesoporous zirconia; the mesoporous zirconia and deionized water are mixed, stirred at a stirring rate of 300 rpm and a temperature of 80 DEG C, and a sodium hydroxide solution is added, and reacted for 6 h to prepare hollow mesoporous zirconia;

[0033] The mass fraction of ammonia water is 25%, the dosage ratio of silica and ammonia water is 3 g:2 mL, the mass fraction of zirconium n-propyl alcohol solution is 70%, the dosage ratio of zirconium n-propyl alcohol solution and silica suspension is 15 mL:150 mL, the molar concentration of sodium hydroxide solution is 1 mol / L, and the dosage ratio of mesoporous zirconia and sodium hydroxide solution is 4 g:18 mL;

[0034] Step A2: the hollow mesoporous zirconia, 2-mercaptobenzothiazole and anhydrous ethanol are mixed and ultrasonically dispersed for 20 min, and reacted for 9 h under the condition of a vacuum degree lower than 2.02 kPa and room temperature, filtered, dried to prepare a loaded mesoporous material, and the loaded mesoporous material is mixed with a cerium nitrate solution, stirred at a stirring rate of 200 rpm and room temperature for 3 min, suction filtered, washed to prepare a precursor;

[0035] The dosage ratio of hollow mesoporous zirconia, 2-mercaptobenzothiazole and anhydrous ethanol is 3 g:8 g:100 mL, the molar concentration of cerium nitrate solution is 0.01 mol / L, and the dosage ratio of loaded mesoporous material and cerium nitrate solution is 4 g:80 mL;

[0036] Step A3: The double-[3-(triethoxysil)propyl]-disulfide and ethanol solution were mixed, stirred and the precursor was added at a stirring rate of 800 rpm and a temperature of 50℃ for 30 min, then irradiated with 100 W ultraviolet light under nitrogen protection at a stirring rate of 120 rpm and a temperature of 80℃ for 2 h to obtain a grafting precursor; the phytic acid and propylene glycol methyl ether were mixed, stirred and the glycidyl methacrylate and tetrabutylammonium bromide were added at a stirring rate of 600 rpm and a temperature of 90℃ under 100 W ultraviolet light irradiation for 1.5 h, then the grafting precursor was added and the reaction was continued for 3 h to obtain the modified filler;

[0037] The mass fraction of the ethanol solution was 90%, the amount of the double-[3-(triethoxysil)propyl]-disulfide and the precursor was 2 mL:2 g; the amount of the phytic acid, the grafting precursor and tetrabutylammonium bromide was 1 g:2 g:0.05 g.

[0038] Example 2

[0039] The modified filler was prepared by the following steps:

[0040] Step A1: Commercial Cabot 80 nm silica, anhydrous ethanol, acetonitrile and ammonia water were mixed and ultrasonically dispersed for 30 min to obtain a silica suspension, then the zirconium n-propyl alcohol solution was slowly added dropwise into the silica suspension at a stirring rate of 800 rpm and room temperature for 7 h to obtain mesoporous zirconia, then the mesoporous zirconia and deionized water were mixed, stirred and the sodium hydroxide solution was added at a stirring rate of 300 rpm and a temperature of 80℃ for 7 h to obtain hollow mesoporous zirconia;

[0041] The mass fraction of the ammonia water was 25%, the amount of the silica and the ammonia water was 3 g:3 mL, the mass fraction of the zirconium n-propyl alcohol solution was 70%, the amount of the zirconium n-propyl alcohol solution and the silica suspension was 18 mL:150 mL, the molar concentration of the sodium hydroxide solution was 1 mol / L, and the amount of the mesoporous zirconia and the sodium hydroxide solution was 4 g:20 mL;

[0042] Step A2: The hollow mesoporous zirconia, 2-mercaptobenzothiazole and anhydrous ethanol were mixed and ultrasonically dispersed for 25 min, then the reaction was carried out at a vacuum degree of less than 2.02 kPa and room temperature for 10 h, followed by filtration and drying to obtain a loaded mesoporous material, then the loaded mesoporous material was mixed with the cerium nitrate solution, stirred at a stirring rate of 280 rpm and room temperature for 3 min, followed by suction filtration and washing to obtain the precursor;

[0043] The hollow mesoporous zirconium oxide, 2-mercaptobenzothiazole and anhydrous ethanol were used in a ratio of 3 g: 10 g: 100 mL, the molar concentration of cerium nitrate solution was 0.01 mol / L, and the hollow mesoporous material and cerium nitrate solution were used in a ratio of 5 g: 100 mL;

[0044] Step A3: The bis-[3-(triethoxysilyl)propyl]-disulfide and ethanol solution were mixed, and the precursor was stirred and added at a stirring rate of 1000 rpm and a temperature of 50℃ for 30 min, and then reacted under the protection of nitrogen at a stirring rate of 180 rpm and a temperature of 80℃ for 2 h under the irradiation of 100 W ultraviolet light, to obtain a grafted precursor. The phytic acid and propylene glycol methyl ether were mixed, and the glycidyl methacrylate and tetrabutylammonium bromide were stirred and added at a stirring rate of 600 rpm and a temperature of 90℃ for 1.5 h under the irradiation of 100 W ultraviolet light, and then the grafted precursor was added and reacted for 3 h, to obtain a modified filler;

[0045] The ethanol solution had a mass fraction of 90%, and the bis-[3-(triethoxysilyl)propyl]-disulfide and the precursor were used in a ratio of 3 mL: 2 g. The phytic acid, the grafted precursor and tetrabutylammonium bromide were used in a ratio of 2 g: 2 g: 0.05 g.

[0046] Example 3

[0047] The modified filler was prepared by the following steps:

[0048] Step A1: Commercial Cabot 80 nm silica, anhydrous ethanol, acetonitrile and ammonia water were mixed and ultrasonically dispersed for 30 min to obtain a silica suspension. The zirconium n-propyl alcohol solution was slowly added dropwise into the silica suspension at a stirring rate of 800 rpm and room temperature, and reacted for 8 h to obtain mesoporous zirconium oxide. The mesoporous zirconium oxide and deionized water were mixed, and the sodium hydroxide solution was stirred and added at a stirring rate of 400 rpm and a temperature of 80℃ for 8 h to obtain hollow mesoporous zirconium oxide.

[0049] The ammonia water had a mass fraction of 25%, and the silica and ammonia water were used in a ratio of 4 g: 3 mL. The zirconium n-propyl alcohol solution had a mass fraction of 70%, and the zirconium n-propyl alcohol solution and the silica suspension were used in a ratio of 20 mL: 150 mL. The sodium hydroxide solution had a molar concentration of 1 mol / L, and the mesoporous zirconium oxide and the sodium hydroxide solution were used in a ratio of 5 g: 20 mL.

[0050] Step A2: hollow mesoporous zirconium oxide, 2-mercaptobenzothiazole and anhydrous ethanol were mixed and ultrasonically dispersed for 25 min, and then were reacted for 12 h at room temperature under a vacuum degree of less than 2.02 kPa, followed by filtration and drying to obtain a loaded mesoporous material, which was mixed with a cerium nitrate solution, stirred for 5 min at room temperature at a stirring rate of 300 rpm, and then was filtered and washed to obtain a precursor;

[0051] The hollow mesoporous zirconium oxide, 2-mercaptobenzothiazole and anhydrous ethanol were used in a ratio of 4 g: 10 g: 100 mL, the molar concentration of the cerium nitrate solution was 0.01 mol / L, and the loaded mesoporous material and the cerium nitrate solution were used in a ratio of 5 g: 100 mL;

[0052] Step A3: bis-[3-(triethoxysilyl)propyl]-disulfide and an ethanol solution were mixed, and then the precursor was added thereto and stirred for 30 min at a stirring rate of 1000 rpm and a temperature of 50℃, and then the mixture was reacted for 2 h under irradiation of 100 W ultraviolet light at a stirring rate of 180 rpm and a temperature of 80℃ to obtain a grafted precursor, and then phytic acid and propylene glycol methyl ether were mixed, and then glycidyl methacrylate and tetrabutylammonium bromide were added thereto and stirred for 2 h under irradiation of 100 W ultraviolet light at a stirring rate of 700 rpm and a temperature of 90℃, and then the grafted precursor was added thereto and the mixture was continuously reacted for 4 h to obtain a modified filler;

[0053] The ethanol solution had a mass fraction of 90%, and the bis-[3-(triethoxysilyl)propyl]-disulfide and the precursor were used in a ratio of 3 mL: 2 g; and the phytic acid, the grafted precursor and tetrabutylammonium bromide were used in a ratio of 2 g: 2 g: 0.05 g.

[0054] Example 4

[0055] The modified silane was prepared by the following steps:

[0056] Step B1: 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, 4-boronic acid phenalene, potassium phosphate tribasic, ethanol and deionized water were mixed, and then tetrakis(triphenylphosphine)palladium was added thereto and stirred for 8 h at a stirring rate of 300 rpm and a temperature of 60℃ to obtain an intermediate 1;

[0057] The 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, 4-boronic acid phenalene, potassium phosphate tribasic and tetrakis(triphenylphosphine)palladium were used in a ratio of 0.1 mol: 0.12 mol: 0.2 mol: 0.1 mol;

[0058] Step B2: Intermediate 1 and acetic acid were mixed, stirred at 200 rpm and 3-buten-1-amine was added at 120 °C for 6 h to produce Intermediate 2;

[0059] The ratio of Intermediate 1 to 3-buten-1-amine was 0.1 mol: 0.2 mol;

[0060] Step B3: Intermediate 2 and toluene were mixed, stirred at 200 rpm and triethoxysilane and Karstedt’s catalyst were added at 70 °C for 24 h to produce the modified silane;

[0061] The ratio of Intermediate 2, triethoxysilane and Karstedt’s catalyst was 0.1 mol: 0.2 mol: 1 mL.

[0062] Example 5

[0063] The modified silane was produced by the following steps:

[0064] Step B1 : 1,7-Dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, 4- boronate benzocyclobutene, potassium phosphate tribasic, ethanol and deionised water were mixed, stirred at 300 rpm and palladium tetrakis(triphenylphosphine) was added at 60 °C for 10 h to produce Intermediate 1 ;

[0065] The ratio of 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, 4- boronate benzocyclobutene, potassium phosphate tribasic and palladium tetrakis(triphenylphosphine) was 0.1 mol: 0.14 mol: 0.2 mol: 0.1 mol;

[0066] Step B2: Intermediate 1 and acetic acid were mixed, stirred at 200 rpm and 3-buten-1-amine was added at 120 °C for 6 h to produce Intermediate 2;

[0067] The ratio of Intermediate 1 to 3-buten-1-amine was 0.1 mol: 0.22 mol;

[0068] Step B3: Intermediate 2 and toluene were mixed, stirred at 200 rpm and triethoxysilane and Karstedt’s catalyst were added at 70 °C for 24 h to produce the modified silane;

[0069] The ratio of Intermediate 2, triethoxysilane and Karstedt’s catalyst was 0.1 mol: 0.22 mol: 1 mL.

[0070] Example 6

[0071] The modified silane was produced by the following steps:

[0072] Step B1: Intermediate 1 was prepared by mixing 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, 4-boronic acid phenalene, potassium phosphate tribasic, ethanol and deionized water, stirring and adding tetrakis(triphenylphosphine)palladium under nitrogen protection at a stirring rate of 300 rpm and a temperature of 60℃, and reacting for 10 h;

[0073] The amount ratio of 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, 4-boronic acid phenalene, potassium phosphate tribasic and tetrakis(triphenylphosphine)palladium was 0.1 mol:0.14 mol:0.2 mol:0.1 mol;

[0074] Step B2: Intermediate 2 was prepared by mixing Intermediate 1 and acetic acid, stirring and adding 3-buten-1-amine at a stirring rate of 300 rpm and a temperature of 120℃, and reacting for 8 h;

[0075] The amount ratio of Intermediate 1 and 3-buten-1-amine was 0.1 mol:0.22 mol;

[0076] Step B3: Modified silane was prepared by mixing Intermediate 2 and toluene, stirring and adding triethoxysilane and Karstedt catalyst under nitrogen protection at a stirring rate of 300 rpm and a temperature of 70℃, and reacting for 24 h;

[0077] The amount ratio of Intermediate 2, triethoxysilane and Karstedt catalyst was 0.1 mol:0.22 mol:2 mL.

[0078] Example 7

[0079] A high-temperature resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy was prepared by the following steps: Step S1: the following raw materials were weighed: 20 parts of commercially available KDD Keding acrylic acid modified epoxy resin, 8 parts of γ-aminopropyl triethoxysilane, 4 parts of modified filler of Example 1, 4 parts of modified silane of Example 4, 1 part of commercially available LJ810 curing agent, 60 parts of ethanol and 20 parts of water;

[0080] Step S2: The acrylic acid modified epoxy resin, ethanol and water were mixed, and the γ-aminopropyl triethoxysilane, modified silane and modified filler were added, stirred for 30 min, and then the curing agent was added and stirred for another 10 min, to obtain a high-temperature resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy;

[0081] Example 8

[0082] A high-temperature resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy is prepared by the following steps: step S1: taking the following raw materials by weight: 25 parts of commercially available KDD KeDing acrylic modified epoxy resin, 10 parts of γ-aminopropyl triethoxysilane, 6 parts of modified filler in Example 2, 4 parts of modified silane in Example 5, 1 part of commercially available LJ810 curing agent, 60 parts of ethanol and 20 parts of water;

[0083] Step S2: mixing the acrylic modified epoxy resin, ethanol and water, adding γ-aminopropyl triethoxysilane, modified silane and modified filler, stirring for 40 min, then adding the curing agent and continuing to stir for 5 min, to prepare a high-temperature resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy.

[0084] Example 9

[0085] A high-temperature resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy is prepared by the following steps: step S1: taking the following raw materials by weight: 25 parts of commercially available KDD KeDing acrylic modified epoxy resin, 8-10 parts of γ-aminopropyl triethoxysilane, 4-6 parts of modified filler in Example 3, 6 parts of modified silane in Example 6, 2 parts of commercially available LJ810 curing agent, 70 parts of ethanol and 25 parts of water;

[0086] Step S2: mixing the acrylic modified epoxy resin, ethanol and water, adding γ-aminopropyl triethoxysilane, modified silane and modified filler, stirring for 40 min, then adding the curing agent and continuing to stir for 5 min, to prepare a high-temperature resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy.

[0087] Comparative Example 1

[0088] Comparative Example 1 and Example 9 are compared, the modified filler is replaced by the precursor in Example 3, and the other steps are the same.

[0089] Comparative Example 2

[0090] Comparative Example 2 and Example 9 are compared, the precursor in the preparation process of the modified filler is replaced by the loaded mesoporous material in Example 3, and the other steps are the same.

[0091] Comparative Example 3

[0092] Comparative Example 3 and Example 9 are compared, the intermediate 1 in Example 6 in the preparation process of the modified silane is replaced by 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, and the other steps are the same.

[0093] Comparative Example 4

[0094] Comparative Example 4 and Example 9 are compared, the modified silane is replaced by γ-aminopropyl triethoxysilane, and the other steps are the same.

[0095] A high-temperature resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy was prepared from the high-temperature resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy prepared in Example 7, Example 8, Example 9, Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4. A commercially available hot-dip galvanizing high-aluminum alloy was prepared into a 50 mm x 80 mm x 1.2 mm substrate. The substrate was immersed in the high-temperature resistant anti-oxidation film forming agent for hot-dip galvanizing high-aluminum alloy at room temperature for 60 s, dried at 120°C for 20 min under light, and the sample was prepared. The adhesion was tested by the cross-cut method according to GB / T 9286-2021. The sample was subjected to temperature rise test according to GB / T 1735-2009. The sample was kept at 400°C for 2 h, taken out and cooled to room temperature. The surface of the sample was virtually divided into 8 equal parts, each part being 25 mm x 20 mm. The cracks, peeling and powdering in each area were observed. The number of occurrences was recorded as one. The high-temperature resistance was represented by the number of occurrences. The adhesion was tested again. According to GB / T 10125-2021, a scalpel was used to scratch the sample along the diagonal line to a depth of 0.1 mm. A 50 g / L NaCl solution with a pH of 7 was used for neutral salt spray corrosion test at 35°C. The sample was taken out after 72 h. The sample surface was washed with water and the dirt and residues at the scratch were removed with a soft sponge. The peeling area near the scratch was removed with adhesive tape. The corrosion resistance of the film forming agent was evaluated by the corrosion rate of the sample (the sum of the area of corrosion and film peeling divided by the total area of the sample). The test results are as follows:

[0096] Test item Example 7 Example 8 Example 9 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Adhesion (grade) 0 0 0 1 0 0 0 High temperature resistance 0 0 0 4 1 3 6 Adhesion of sample panel after temperature rise test (grade) 1 1 1 4 2 3 4 Corrosion rate (%) 18 16 17 26 34 19 18

[0097] As shown in the table, the performance of Example 7, Example 8 and Example 9 was compared with Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4. In Comparative Example 1, the modified filler was replaced by a precursor. Since the surface of the precursor was not grafted with phytic acid, it could not effectively combine with other substances in the film forming agent, resulting in a significant decrease in the performance of the film forming agent. In Comparative Example 2, the precursor was replaced by a loaded mesoporous material during the preparation of the modified filler. Since the loaded mesoporous material was not sealed, the corrosion inhibitor loaded therein was unloaded during the subsequent reaction, resulting in a significant decrease in the corrosion resistance of the film forming agent. In Comparative Example 3, the intermediate 1 was replaced by 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride during the preparation of the modified silane. Since there was no benzocyclobutene group, it could not self-crosslink under high temperature conditions, resulting in a certain decrease in the high-temperature resistance. In Comparative Example 4, the modified silane was replaced by γ-aminopropyltriethoxysilane, and the high-temperature resistance of the film forming agent decreased significantly.

[0098] In the description, references to "one embodiment," "an example," "certain examples" etc. mean that the particular feature, structure, material, or characteristic being described is included in at least one embodiment or example of the application. The appearances of an item in various examples is not necessarily indicative of several embodiments or examples, that include the item. Furthermore, the particular features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples. It will also be appreciated by those of skill in the art that references to a structure or feature that is "near" another feature can be interpreted also to include an indirect connection, where components that are not directly connected can be connected through other components or by way of an indirect communication means. It will be apparent to those skilled in the art that various modifications and variations can be made to the present application without departing from the spirit or scope of the application. Thus, it is intended that the present application cover modifications and variations of this application provided they come within the scope of the appended claims and their equivalents.

[0099] The above merely illustrates and explains the concept of the present application, and those skilled in the art can make various modifications or supplements to the described specific embodiments or adopt similar ways to replace them, as long as they do not deviate from the concept of the present application or exceed the scope defined by the claims.

Claims

1. A high-temperature-resistant anti-oxidation film forming agent for a hot-dip galvanizing high-aluminum alloy, characterized by comprising: It is prepared by the following steps: step S1: take the following weight parts of raw materials: 20-25 parts of acrylic modified epoxy resin, 8-10 parts of gamma-aminopropyl triethoxysilane, 4-6 parts of modified filler, 4-6 parts of modified silane, 1-2 parts of curing agent, 60-70 parts of ethanol and 20-25 parts of water; Step S2: mix the acrylic modified epoxy resin, ethanol and water, add gamma-aminopropyl triethoxysilane, modified silane and modified filler, stir for 30-40 min, then add curing agent, continue to stir for 5-10 min, prepare a high-temperature resistant and oxidation resistant film forming agent for hot-dip galvanizing high-aluminum alloy; The modified filler is prepared by the following steps: Step A1: mix silica, anhydrous ethanol, acetonitrile and ammonia water and ultrasonic dispersion for 30 min to prepare a silica suspension, slowly drop zirconium n-propyl alcohol solution into the silica suspension at a stirring rate of 700-800 rpm under room temperature conditions, react for 6-8 h to prepare mesoporous zirconium oxide, mix mesoporous zirconium oxide and deionized water, stir at a stirring rate of 300-400 rpm under the condition of 80℃, and add sodium hydroxide solution, react for 6-8 h to prepare hollow mesoporous zirconium oxide; Step A2: mix hollow mesoporous zirconium oxide, 2-mercaptobenzothiazole and anhydrous ethanol, ultrasonic dispersion for 20-25 min, react for 9-12 h under the condition of vacuum degree less than 2.02 kPa and room temperature, filter and dry to prepare a loaded mesoporous material, mix the loaded mesoporous material with cerium nitrate solution, stir for 3-5 min at a stirring rate of 200-300 rpm under room temperature conditions, and prepare a precursor by filtration and washing; Step A3: mix bis-[3-(triethoxysil)propyl]-disulfide and ethanol solution, stir at a stirring rate of 800-1000 rpm under the condition of 50℃, add the precursor, react for 30 min, then react for 2 h under the condition of nitrogen protection, 100W ultraviolet light irradiation, a stirring rate of 120-180 rpm and 80℃ to prepare a grafted precursor, mix phytic acid and propylene glycol methyl ether, stir at a stirring rate of 600-700 rpm under the condition of 100W ultraviolet light irradiation and 90℃, add glycidyl methacrylate and tetrabutylammonium bromide, react for 1.5-2 h, then add the grafted precursor and continue to react for 3-4 h to prepare the modified filler; The modified silane is prepared by the following steps: Step B1: mix 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, 4-boronic acid phenylcyclobutene, potassium phosphate trihydrate, ethanol and deionized water, stir under the condition of nitrogen protection, a stirring rate of 200-300 rpm and 60℃, add tetrakis(triphenylphosphine)palladium, react for 8-10 h to prepare intermediate 1; Step B2: mix intermediate 1 and acetic acid, stir at a stirring rate of 200-300 rpm and 120℃, add 3-butene-1-amine, react for 6-8 h to prepare intermediate 2; Step B3: Intermediate 2 and toluene were mixed, stirred at 70°C under nitrogen protection at a stirring rate of 200-300 rpm, and then triethoxysilane and Karstedt catalyst were added and stirred for 24 h to obtain the modified silane.

2. The high-temperature oxidation resistant film forming agent for hot-dip galvanizing high-aluminum alloy according to claim 1, characterized by comprising: In the step A1, the mass fraction of ammonia was 25%, the amount ratio of silica and ammonia was 3-4 g:2-3 mL, the mass fraction of zirconium n-propyl alcohol solution was 70%, the amount ratio of zirconium n-propyl alcohol solution and silica suspension was 15-20 mL:150 mL, the molar concentration of sodium hydroxide solution was 1 mol / L, and the amount ratio of mesoporous zirconia and sodium hydroxide solution was 4-5 g:18-20 mL.

3. The high-temperature oxidation resistant film forming agent for hot-dip galvanizing high-aluminum alloy according to claim 1, characterized by comprising: In the step A2, the amount ratio of hollow mesoporous zirconia, 2-mercaptobenzothiazole and anhydrous ethanol was 3-4 g:8-10 g:100 mL, the molar concentration of cerium nitrate solution was 0.01 mol / L, and the amount ratio of loaded mesoporous material and cerium nitrate solution was 4-5 g:80-100 mL.

4. The high-temperature oxidation resistant film forming agent for hot-dip galvanizing high-aluminum alloy according to claim 1, characterized by comprising: In the step A3, the mass fraction of ethanol solution was 90%, the amount ratio of bis-[3-(triethoxysilyl)propyl]-disulfide and precursor was 2-3 mL:2 g, the amount ratio of phytic acid, grafted precursor and tetrabutylammonium bromide was 1-2 g:2 g:0.05 g.

5. The high-temperature oxidation resistant film forming agent for hot-dip galvanizing high-aluminum alloy according to claim 1, characterized by comprising: In the step B1, the amount ratio of 1,7-dibromo-3,4,9,10-perylenetetracarboxylic dianhydride, 4-boronic acid phenylcyclobutene, potassium phosphate trihydrate and tetrakis(triphenylphosphine)palladium was 0.1 mol:0.12-0.14 mol:0.2 mol:0.1 mol.

6. The high-temperature oxidation resistant film forming agent for hot-dip galvanizing high-aluminum alloy according to claim 1, characterized by comprising: In the step B2, the amount ratio of intermediate 1 and 3-buten-1-amine was 0.1 mol:0.2-0.22 mol.

7. The high-temperature oxidation resistant film forming agent for hot-dip galvanizing high-aluminum alloy according to claim 1, characterized by comprising 0.1 to 0.5% of the element B. In the step B3, the amount ratio of intermediate 2, triethoxysilane and Karstedt catalyst was 0.1 mol:0.2-0.22 mol:1-2 mL.