High-strength antifouling porcelain insulator and preparation method thereof

Abstract

The invention discloses a preparation method of a high-strength antifouling porcelain insulator. The preparation method comprises the following steps: (1) preparing doped powder; (2) preparing modified powder; (3) heating toluene diisocynate in a water bath to 82 + / -2 DEG C, preserving heat, then adding dehydrated polyether polyol, stirring for 3 hours, then naturally cooling to normal temperature, adding the modified powder, gamma-glycidyl ether oxypropyl trimethoxy silane, polymethylene polyphenyl polyisocyanate, acetone, 2, 4-diaminotoluene and deionized water, adding materials, stirring and mixing to obtain a coating; and (4) spraying the coating on the surface of a porcelain insulator substrate, drying, and placing at room temperature to obtain the high-strength antifouling porcelain insulator. The porcelain insulator coating prepared by the method has good hydrophobicity and scratch resistance, the water contact angle is larger, sewage is not easy to adhere, the anti-pollution capability is strong, the coating strength is higher, the adhesive force is strong, the coating is not easy to fall off, and the durability of the porcelain insulator is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of insulator coatings, and particularly relates to a high-strength anti-pollution porcelain insulator and a preparation method thereof. Background Art

[0002] As one of the components widely used in the power grid, insulators are affected by different pollution sources such as dust or air pollution, which will cause the surface of the insulators of outdoor transmission lines to be contaminated. Especially for porcelain insulators, due to their inherent surface hydrophilicity, their pollution resistance is weaker than that of composite insulators. When encountering humid weather such as rain or fog, the soluble electrolytes in the surface contamination of porcelain insulators absorb moisture to form a conductive water film, which may reduce the resistance of the contamination layer by several orders of magnitude compared with that in the dry state, resulting in an increase in leakage current, a decrease in its insulation performance, and a significant increase in the probability of pollution discharge and flashover. Summary of the Invention

[0003] For this reason, the present invention provides a preparation method of a high-strength anti-pollution porcelain insulator, and the steps include:

[0004] (1) Prepare an aqueous solution of cerium nitrate; prepare an ethanol solution of tetrabutyl titanate; prepare an ethanol solution of tetraethoxysilane; while stirring, add the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane to the aqueous solution of cerium nitrate at the same time. After the addition is completed, continue to stir the solution for more than 6 hours, then add ammonia water to adjust the pH of the solution to 9-10, and then stir the solution for more than 2 hours. After stirring is completed, perform solid-liquid separation. The solid phase is washed with deionized water for more than 3 times, dried, and calcined at 500-550 °C for more than 2 hours to obtain a doped powder;

[0005] (2) Prepare an ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in a reaction kettle; add the doped powder to Tris-HCl buffer solution, and stir for more than 30 minutes under an ultrasonic environment to obtain a suspension. Stir the suspension, and then add dopamine to the suspension while stirring. After the addition is completed, continue to stir the suspension for more than 40 hours. Perform solid-liquid separation. The solid phase is washed with deionized water for more than 3 times, dried, and the dried solid phase is immersed in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in the reaction kettle, and stirred for more than 10 minutes. Then, add mercaptoacetic acid while stirring. After the addition, continue to stir for more than 30 minutes. Seal the reaction kettle, heat it to 140±5 °C and keep it warm for more than 60 minutes, and then naturally cool it to room temperature. Open the reaction kettle, perform solid-liquid separation. The solid phase is washed with ethanol for more than 2 times, and then washed with deionized water for more than 2 times, and dried to obtain a modified powder;

[0006] (3) Heat toluene diisocyanate in a water bath to 82 ± 2 °C and keep it warm, then add the dehydrated polyether polyol. After the feeding is completed, continue to stir at a constant temperature of 82 ± 2 °C for more than 3 h, then naturally cool to room temperature, add the modified powder, γ-glycidoxypropyltrimethoxysilane, polymethylene polyphenyl polyisocyanate, acetone, 2,4-diaminotoluene and deionized water. After feeding, stir and mix for more than 2 h to obtain the coating;

[0007] (4) Spray the coating on the surface of the porcelain insulator substrate, then heat it to 60 ± 5 °C in a nitrogen atmosphere and dry for more than 5 h, then place it at room temperature for more than 12 h to obtain the high-strength anti-pollution porcelain insulator.

[0008] Further, in the step (1), in the aqueous solution of cerium nitrate, the concentration of cerium nitrate is 20 - 25 g / L, and the solvent is water; in the ethanol solution of tetrabutyl titanate, the mass percentage of tetrabutyl titanate is 16% - 18%, and the solvent is ethanol; in the ethanol solution of tetraethoxysilane, the mass percentage of tetraethoxysilane is 8% - 10%, and the solvent is ethanol; the volume ratio of the aqueous solution of cerium nitrate, the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane is aqueous solution of cerium nitrate:ethanol solution of tetrabutyl titanate:ethanol solution of tetraethoxysilane = 3 - 5:10:4 - 7.

[0009] Further, in the step (1), the mass percentage of the solute in the ammonia water is 10%.

[0010] Further, in the step (2), the amount ratio of the doped powder added to the Tris-HCl buffer solution is doped powder:Tris-HCl buffer solution = 8 - 10 g:1 L; the mass ratio of the added dopamine to the mass of the doped powder added to prepare the suspension is doped powder:dopamine = 8 - 10 g:15 - 18 g.

[0011] Further, in the step (2), in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol, the concentration of 1H,1H,2H,2H-perfluorodecanethiol is 20 - 30 g / L, and the solvent is ethanol; the amount ratio of the dried solid phase, mercaptoacetic acid added to the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol is dried solid phase:mercaptoacetic acid:ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol = 2 - 3 g:7 - 9 g:200 mL.

[0012] Further, in the step (3), the raw materials used are as follows by weight: 30 parts of dehydrated polyether polyol, 50 parts of toluene diisocyanate, 15 - 18 parts of modified powder, 8 - 10 parts of γ - glycidoxypropyltrimethoxysilane, 8 - 10 parts of polymethylene polyphenyl polyisocyanate, 40 - 50 parts of acetone, 5 - 6 parts of 2,4 - diaminotoluene, and 100 - 120 parts of deionized water.

[0013] The beneficial effects of the present invention are as follows: The porcelain insulator coating prepared by the method of the present invention has good hydrophobicity and scratch resistance, a large water contact angle, is not easily attached to sewage, has strong anti - pollution ability, and the coating has high strength, strong adhesion, is not easily peeled off, and improves the durability of the porcelain insulator. By adding the modified powder prepared in the present invention, the hydrophobicity and adhesion of the coating can be significantly improved. This is mainly because: the present invention first obtains the doped cerium titanium - silicon composite oxide powder by the doping thermal decomposition method. By doping cerium to partially replace the position of Ti 4+ ions, it can increase the micro - nano structures such as "concave - angle structure" or "hierarchical structure" on the particle surface. The curvature radians formed by these structures can generate an upward Laplace pressure, improving the liquid - repellency of the material surface and showing a higher contact angle. Subsequently, through polydopamine modification, on the one hand, a large number of amino groups are formed on the particle surface, preparing for the subsequent modification process; on the other hand, the particles modified by polydopamine can form a network - like porous structure in the coating. The porous structure can make more air stay in the coating to form an "air cushion layer", improving the hydrophobicity of the coating. At the same time, the network structure improves the strength of the coating, manifested as an increase in scratch resistance. Subsequently, graft modification with 1H,1H,2H,2H - perfluorodecanethiol and mercaptoacetic acid endows the coating surface with more excellent hydrophobicity through the perfluoroalkyl chain, and the terminal carboxyl group improves the dispersibility of the particles and at the same time improves the binding force between the particles and other components in the coating. Specific embodiments

[0014] The following further illustrates the present invention with reference to the embodiments.

[0015] Example 1

[0016] A preparation method of a high - strength anti - pollution porcelain insulator, the steps include:

[0017] (1) Prepare an aqueous solution of cerium nitrate; in the aqueous solution of cerium nitrate, the concentration of cerium nitrate is 20 g / L and the solvent is water; prepare an ethanol solution of tetrabutyl titanate; in the ethanol solution of tetrabutyl titanate, the mass percentage of tetrabutyl titanate is 16%, and the solvent is ethanol; prepare an ethanol solution of tetraethoxysilane; in the ethanol solution of tetraethoxysilane, the mass percentage of tetraethoxysilane is 8%, and the solvent is ethanol; while stirring, add the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane to the aqueous solution of cerium nitrate at the same time. The volume ratio of the aqueous solution of cerium nitrate, the ethanol solution of tetrabutyl titanate, and the ethanol solution of tetraethoxysilane is aqueous solution of cerium nitrate:ethanol solution of tetrabutyl titanate:ethanol solution of tetraethoxysilane = 3:10:4; after the addition is completed, continue to stir the solution for 6 h, then add ammonia water to adjust the pH of the solution to 9, and the mass percentage of the solute in the ammonia water is 10%; stir the solution for another 2 h, after the stirring is completed, perform solid-liquid separation, wash the solid phase with deionized water 3 times, dry it at 60 °C for 4 h, and calcine it at 500 °C for 2 h; obtain the doped powder;

[0018] (2) Prepare an ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in a reaction kettle; in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol, the concentration of 1H,1H,2H,2H-perfluorodecanethiol is 20 g / L and the solvent is ethanol; add the doped powder to Tris-HCl buffer solution (10 mmol / L, pH = 8.5). The amount ratio of the doped powder added to the Tris-HCl buffer solution is doped powder:Tris-HCl buffer solution = 8 g:1 L; stir and disperse for 30 min in an ultrasonic environment to obtain a suspension. Stir the suspension, and then add dopamine to the suspension while stirring. The mass ratio of the added dopamine to the mass of the doped powder added to prepare the suspension is doped powder:dopamine = 8 g:15 g; after the addition is completed, continue to stir the suspension for 40 h, perform solid-liquid separation, wash the solid phase with deionized water 3 times, dry it at 60 °C for 4 h, soak the dried solid phase in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in the reaction kettle, stir for 10 min, and then add mercaptoacetic acid while stirring. The amount ratio of the dried solid phase, mercaptoacetic acid, and the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol added to the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol is dried solid phase:mercaptoacetic acid:ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol = 2 g:7 g:200 mL; after the addition, continue to stir for 30 min, seal the reaction kettle, heat it to 140 °C and keep it warm for 60 min, then naturally cool it to room temperature, open the reaction kettle, perform solid-liquid separation, wash the solid phase with ethanol 2 times, then wash it with deionized water 2 times, and dry it at 60 °C for 4 h to obtain the modified powder;

[0019] (3) Heat toluene diisocyanate in a water bath to 82 °C and keep it warm. Then add the dehydrated polyether polyol (DJ-12). After the addition is completed, continue stirring at a constant temperature of 82 °C for 3 h, and then naturally cool to room temperature. Add the modified powder, γ-glycidoxypropyltrimethoxysilane, polymethylene polyphenyl polyisocyanate, acetone, 2,4-diaminotoluene, and deionized water. After the addition, stir and mix for 2 h to obtain the coating. The amounts of each raw material used are as follows by weight: 30 parts of dehydrated polyether polyol, 50 parts of toluene diisocyanate, 15 parts of modified powder, 8 parts of γ-glycidoxypropyltrimethoxysilane, 8 parts of polymethylene polyphenyl polyisocyanate, 40 parts of acetone, 5 parts of 2,4-diaminotoluene, and 100 parts of deionized water;

[0020] (4) Spray the coating on the surface of the porcelain insulator substrate with a film thickness of 500 μm. Then heat it to 60 °C in a nitrogen atmosphere and dry for 5 h, and then place it at room temperature for 12 h to obtain the high-strength anti-pollution porcelain insulator.

[0021] Example 2

[0022] A preparation method of a high-strength anti-pollution porcelain insulator, the steps include:

[0023] (1) Prepare an aqueous solution of cerium nitrate; in the aqueous solution of cerium nitrate, the concentration of cerium nitrate is 20 g / L and the solvent is water; prepare an ethanol solution of tetrabutyl titanate; in the ethanol solution of tetrabutyl titanate, the mass percentage of tetrabutyl titanate is 17% and the solvent is ethanol; prepare an ethanol solution of tetraethoxysilane; in the ethanol solution of tetraethoxysilane, the mass percentage of tetraethoxysilane is 9% and the solvent is ethanol; while stirring, add the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane to the aqueous solution of cerium nitrate at the same time. The volume ratio of the aqueous solution of cerium nitrate, the ethanol solution of tetrabutyl titanate, and the ethanol solution of tetraethoxysilane is aqueous solution of cerium nitrate:ethanol solution of tetrabutyl titanate:ethanol solution of tetraethoxysilane = 4:10:5; after the addition is completed, continue stirring the solution for 6 h, and then add ammonia water to adjust the pH of the solution to 9. The mass percentage of the solute in the ammonia water is 10%; then stir the solution for 2 h. After the stirring is completed, perform solid-liquid separation. The solid phase is washed 3 times with deionized water, dried at 60 °C for 4 h, and calcined at 500 °C for 2 h; obtain the doped powder;

[0024] (2) Prepare an ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in a reaction kettle; in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol, the concentration of 1H,1H,2H,2H-perfluorodecanethiol is 20 g / L, and the solvent is ethanol; add the doped powder to Tris-HCl buffer solution (10 mmol / L, pH = 8.5), and the dosage ratio of the doped powder to Tris-HCl buffer solution is doped powder:Tris-HCl buffer solution = 9 g:1 L; stir and disperse for 30 min in an ultrasonic environment to obtain a suspension, stir the suspension, and then add dopamine to the suspension under stirring. The mass ratio of the added dopamine to the doped powder added to prepare the suspension is doped powder:dopamine = 9 g:16 g; after the feeding is completed, continue to stir the suspension for 40 h, perform solid-liquid separation, wash the solid phase with deionized water 3 times, dry at 60 °C for 4 h, soak the dried solid phase in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in the reaction kettle, stir for 10 min, and then add mercaptoacetic acid under stirring. The dosage ratio of the dried solid phase, mercaptoacetic acid, and the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol added to the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol is dried solid phase:mercaptoacetic acid:ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol = 2 g:8 g:200 mL; after feeding, continue to stir for 30 min, seal the reaction kettle, heat to 140 °C and keep warm for 60 min, then naturally cool to room temperature, open the reaction kettle, perform solid-liquid separation, wash the solid phase with ethanol 2 times, then wash with deionized water 2 times, and dry at 60 °C for 4 h to obtain a modified powder;

[0025] (3) Heat toluene diisocyanate in a water bath to 82 °C and keep warm, then add dehydrated polyether polyol (DJ-12). After the feeding is completed, continue to stir at 82 °C for 3 h, then naturally cool to room temperature, add the modified powder, γ-glycidoxypropyltrimethoxysilane, polymethylene polyphenyl polyisocyanate, acetone, 2,4-diaminotoluene, and deionized water. After feeding, stir and mix for 2 h to obtain a coating; the amounts of each raw material used are as follows by weight: 30 parts of dehydrated polyether polyol, 50 parts of toluene diisocyanate, 16 parts of modified powder, 9 parts of γ-glycidoxypropyltrimethoxysilane, 9 parts of polymethylene polyphenyl polyisocyanate, 45 parts of acetone, 5 parts of 2,4-diaminotoluene, and 110 parts of deionized water;

[0026] (4) Spray the coating on the surface of the porcelain insulator substrate, and the coating thickness is 500 μm; then heat to 60 °C in a nitrogen atmosphere and dry for 5 h, and then place at room temperature for 12 h to obtain the high-strength anti-fouling porcelain insulator.

[0027] Example 3

[0028] A preparation method of a high-strength anti-fouling porcelain insulator, the steps including:

[0029] (1) Prepare an aqueous solution of cerium nitrate; in the aqueous solution of cerium nitrate, the concentration of cerium nitrate is 25 g / L, and the solvent is water; prepare an ethanol solution of tetrabutyl titanate; in the ethanol solution of tetrabutyl titanate, the mass percentage of tetrabutyl titanate is 17%, and the solvent is ethanol; prepare an ethanol solution of tetraethoxysilane; in the ethanol solution of tetraethoxysilane, the mass percentage of tetraethoxysilane is 9%, and the solvent is ethanol; while stirring, add the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane to the aqueous solution of cerium nitrate at the same time, and the volume ratio of the aqueous solution of cerium nitrate, the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane is aqueous solution of cerium nitrate:ethanol solution of tetrabutyl titanate:ethanol solution of tetraethoxysilane = 4:10:6; after the feeding is completed, continue to stir the solution for 6 h, then add ammonia water to adjust the pH of the solution to 9, and the mass percentage of the solute in the ammonia water is 10%; stir the solution for another 2 h, after the stirring is completed, perform solid-liquid separation, wash the solid phase with deionized water 3 times, dry it at 60 °C for 4 h, and calcine it at 550 °C for 2 h; obtain doped powder;

[0030] (2) Prepare an ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in a reaction kettle; in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol, the concentration of 1H,1H,2H,2H-perfluorodecanethiol is 30 g / L, and the solvent is ethanol; add the doped powder to Tris-HCl buffer solution (10 mmol / L, pH = 8.5), and the ratio of the doped powder added to the Tris-HCl buffer solution is doped powder:Tris-HCl buffer solution = 9 g:1 L; stir and disperse in an ultrasonic environment for 30 min to obtain a suspension, stir the suspension, and then add dopamine to the suspension while stirring, and the mass ratio of the added dopamine to the doped powder added to prepare the suspension is doped powder:dopamine = 9 g:17 g; after the feeding is completed, continue to stir the suspension for 40 h, perform solid-liquid separation, wash the solid phase with deionized water 3 times, dry it at 60 °C for 4 h, soak the dried solid phase in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in the reaction kettle, stir for 10 min, and then add mercaptoacetic acid while stirring. The ratio of the dried solid phase, mercaptoacetic acid added to the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol is dried solid phase:mercaptoacetic acid:ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol = 3 g:8 g:200 mL; after the feeding, continue to stir for 30 min, seal the reaction kettle, heat it to 140 °C and keep it warm for 60 min, then naturally cool it to room temperature, open the reaction kettle, perform solid-liquid separation, wash the solid phase with ethanol 2 times, then wash it with deionized water 2 times, and dry it at 60 °C for 4 h to obtain modified powder;

[0031] (3) Heat toluene diisocyanate in a water bath to 82 °C and keep it warm, then add the dehydrated polyether polyol (DJ-12). After the feeding is completed, continue stirring at 82 °C for 3 h, then naturally cool to room temperature. Add the modified powder, γ-glycidoxypropyltrimethoxysilane, polymethylene polyphenyl polyisocyanate, acetone, 2,4-diaminotoluene and deionized water. After feeding, stir and mix for 2 h to obtain the coating. The amounts of each raw material used are as follows by weight: 30 parts of dehydrated polyether polyol, 50 parts of toluene diisocyanate, 17 parts of modified powder, 9 parts of γ-glycidoxypropyltrimethoxysilane, 9 parts of polymethylene polyphenyl polyisocyanate, 45 parts of acetone, 6 parts of 2,4-diaminotoluene, and 110 parts of deionized water;

[0032] (4) Spray the coating on the surface of the porcelain insulator matrix with a coating thickness of 500 μm; then heat it to 60 °C in a nitrogen atmosphere and dry for 5 h, and then place it at room temperature for 12 h to obtain the high-strength anti-pollution porcelain insulator.

[0033] Example 4

[0034] A preparation method of a high-strength anti-pollution porcelain insulator, the steps include:

[0035] (1) Prepare an aqueous solution of cerium nitrate; in the aqueous solution of cerium nitrate, the concentration of cerium nitrate is 25 g / L and the solvent is water; prepare an ethanol solution of tetrabutyl titanate; in the ethanol solution of tetrabutyl titanate, the mass percentage of tetrabutyl titanate is 18%, and the solvent is ethanol; prepare an ethanol solution of tetraethoxysilane; in the ethanol solution of tetraethoxysilane, the mass percentage of tetraethoxysilane is 10%, and the solvent is ethanol; while stirring, add the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane to the aqueous solution of cerium nitrate at the same time. The volume ratio of the aqueous solution of cerium nitrate, the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane is aqueous solution of cerium nitrate:ethanol solution of tetrabutyl titanate:ethanol solution of tetraethoxysilane = 5:10:7; after the feeding is completed, continue stirring the solution for 6 h, then add ammonia water to adjust the pH of the solution to 9, and the mass percentage of the solute in the ammonia water is 10%; then stir the solution for 2 h. After the stirring is completed, perform solid-liquid separation. The solid phase is washed 3 times with deionized water, dried at 60 °C for 4 h, and calcined at 550 °C for 2 h; obtain the doped powder;

[0036] (2) Prepare an ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in a reaction kettle; in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol, the concentration of 1H,1H,2H,2H-perfluorodecanethiol is 30 g / L, and the solvent is ethanol; add the doped powder into Tris-HCl buffer solution (10 mmol / L, pH = 8.5), and the dosage ratio of the doped powder added into Tris-HCl buffer solution is doped powder:Tris-HCl buffer solution = 10 g:1 L; stir and disperse for 30 min in an ultrasonic environment to obtain a suspension, stir the suspension, and then add dopamine to the suspension under stirring, and the mass ratio of the added dopamine to the doped powder added to prepare the suspension is doped powder:dopamine = 10 g:18 g; after the feeding is completed, continue to stir the suspension for 40 h, perform solid-liquid separation, wash the solid phase with deionized water 3 times, dry at 60 °C for 4 h, soak the dried solid phase in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in the reaction kettle, stir for 10 min, and then add thioglycolic acid under stirring. The dosage ratio of the dried solid phase, thioglycolic acid and the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol added into the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol is dried solid phase:thioglycolic acid:1H,1H,2H,2H-perfluorodecanethiol ethanol solution = 3 g:9 g:200 mL; continue to stir for 30 min after feeding, seal the reaction kettle, heat to 140 °C and keep warm for 60 min, then naturally cool to room temperature, open the reaction kettle, perform solid-liquid separation, wash the solid phase with ethanol 2 times, then wash with deionized water 2 times, and dry at 60 °C for 4 h to obtain a modified powder;

[0037] (3) Heat toluene diisocyanate in a water bath to 82 °C and keep warm, then add dehydrated polyether polyol (DJ-12), continue to stir at 82 °C for 3 h after the feeding is completed, then naturally cool to room temperature, add the modified powder, γ-glycidoxypropyltrimethoxysilane, polymethylene polyphenyl polyisocyanate, acetone, 2,4-diaminotoluene and deionized water, stir and mix for 2 h after feeding to obtain a coating; the amounts of each raw material used are as follows by weight: 30 parts of dehydrated polyether polyol, 50 parts of toluene diisocyanate, 18 parts of modified powder, 10 parts of γ-glycidoxypropyltrimethoxysilane, 10 parts of polymethylene polyphenyl polyisocyanate, 50 parts of acetone, 6 parts of 2,4-diaminotoluene, and 120 parts of deionized water;

[0038] (4) Spray the coating on the surface of the porcelain insulator matrix, and the coating thickness is 500 μm; then heat to 60 °C and dry for 5 h in a nitrogen atmosphere, and then place at room temperature for 12 h to obtain the high-strength anti-fouling porcelain insulator.

[0039] Comparative Example 1

[0040] A preparation method of an insulator for comparison, the steps include:

[0041] (1) Prepare an ethanol solution of tetrabutyl titanate; in the ethanol solution of tetrabutyl titanate, the mass percentage of tetrabutyl titanate is 17%, and the solvent is ethanol; prepare an ethanol solution of tetraethoxysilane; in the ethanol solution of tetraethoxysilane, the mass percentage of tetraethoxysilane is 9%, and the solvent is ethanol; while stirring, add the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane to deionized water at the same time. The volume ratio of deionized water, the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane is deionized water: ethanol solution of tetrabutyl titanate: ethanol solution of tetraethoxysilane = 4:10:6; after the feeding is completed, continue to stir the solution for 6 h, then add ammonia water to adjust the pH of the solution to 9, and the mass percentage of the solute in the ammonia water is 10%; then stir the solution for 2 h, after the stirring is completed, perform solid-liquid separation, wash the solid phase with deionized water 3 times, dry at 60 °C for 4 h, and calcine at 550 °C for 2 h; obtain the doped powder of this comparative example;

[0042] (2) Prepare an ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in a reaction kettle; in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol, the concentration of 1H,1H,2H,2H-perfluorodecanethiol is 30 g / L, and the solvent is ethanol; add the doped powder to Tris-HCl buffer solution (10 mmol / L, pH = 8.5), and the ratio of the doped powder added to the Tris-HCl buffer solution is doped powder: Tris-HCl buffer solution = 9 g: 1 L; stir and disperse for 30 min in an ultrasonic environment to obtain a suspension, stir the suspension, and then add dopamine to the suspension while stirring. The mass ratio of the added dopamine to the doped powder added to prepare the suspension is doped powder: dopamine = 9 g: 17 g; after the feeding is completed, continue to stir the suspension for 40 h, perform solid-liquid separation, wash the solid phase with deionized water 3 times, dry at 60 °C for 4 h, soak the dried solid phase in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in the reaction kettle, stir for 10 min, and then add mercaptoacetic acid while stirring. The ratio of the dried solid phase, mercaptoacetic acid and the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol added to the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol is dried solid phase: mercaptoacetic acid: ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol = 3 g: 8 g: 200 mL; after the feeding, continue to stir for 30 min, seal the reaction kettle, heat to 140 °C and keep warm for 60 min, then naturally cool to room temperature, open the reaction kettle, perform solid-liquid separation, wash the solid phase with ethanol 2 times, then wash with deionized water 2 times, and dry at 60 °C for 4 h to obtain the modified powder;

[0043] (3) Heat toluene diisocyanate in a water bath to 82 °C and keep it warm. Then add the dehydrated polyether polyol (DJ-12). After the addition is completed, continue to stir at a constant temperature of 82 °C for 3 h, and then naturally cool to room temperature. Add the modified powder, γ-glycidoxypropyltrimethoxysilane, polymethylene polyphenyl polyisocyanate, acetone, 2,4-diaminotoluene, and deionized water. After the addition, stir and mix for 2 h to obtain the coating. The amounts of each raw material used are as follows by weight: 30 parts of dehydrated polyether polyol, 50 parts of toluene diisocyanate, 17 parts of modified powder, 9 parts of γ-glycidoxypropyltrimethoxysilane, 9 parts of polymethylene polyphenyl polyisocyanate, 45 parts of acetone, 6 parts of 2,4-diaminotoluene, and 110 parts of deionized water;

[0044] (4) Spray the coating on the surface of the porcelain insulator substrate with a film thickness of 500 μm. Then heat it to 60 °C in a nitrogen atmosphere and dry for 5 h, and then place it at room temperature for 12 h to obtain the insulator of this comparative example.

[0045] Comparative Example 2

[0046] A preparation method of an insulator for comparison, the steps include:

[0047] (1) Prepare an aqueous solution of cerium nitrate; in the aqueous solution of cerium nitrate, the concentration of cerium nitrate is 25 g / L and the solvent is water; prepare an ethanol solution of tetrabutyl titanate; in the ethanol solution of tetrabutyl titanate, the mass percentage of tetrabutyl titanate is 17% and the solvent is ethanol; prepare an ethanol solution of tetraethoxysilane; in the ethanol solution of tetraethoxysilane, the mass percentage of tetraethoxysilane is 9% and the solvent is ethanol; while stirring, add the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane to the aqueous solution of cerium nitrate at the same time. The volume ratio of the aqueous solution of cerium nitrate, the ethanol solution of tetrabutyl titanate, and the ethanol solution of tetraethoxysilane is aqueous solution of cerium nitrate:ethanol solution of tetrabutyl titanate:ethanol solution of tetraethoxysilane = 4:10:6; after the addition is completed, continue to stir the solution for 6 h, and then add ammonia water to adjust the pH of the solution to 9. The mass percentage of the solute in the ammonia water is 10%; then stir the solution for 2 h. After the stirring is completed, perform solid-liquid separation. The solid phase is washed 3 times with deionized water, dried at 60 °C for 4 h, and calcined at 550 °C for 2 h; obtain the doped powder;

[0048] (2) Prepare an ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in a reaction kettle; in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol, the concentration of 1H,1H,2H,2H-perfluorodecanethiol is 30 g / L, and the solvent is ethanol; immerse the doped powder in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in the reaction kettle, stir for 10 min, and then add thioglycolic acid under stirring. The dosage ratio of the doped powder, thioglycolic acid and the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol added to the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol is doped powder:thioglycolic acid:ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol = 3 g:8 g:200 mL; continue to stir for 30 min after feeding, seal the reaction kettle, heat to 140 °C and keep warm for 60 min, then naturally cool to room temperature, open the reaction kettle, separate the solid and liquid, wash the solid phase with ethanol twice, then wash it with deionized water twice, and dry it at 60 °C for 4 h to obtain the modified powder;

[0049] (3) Heat toluene diisocyanate in a water bath to 82 °C and keep warm, then add dehydrated polyether polyol (DJ-12). After the feeding is completed, continue to stir at 82 °C for 3 h, then naturally cool to room temperature, and add the modified powder, γ-glycidoxypropyltrimethoxysilane, polymethylene polyphenyl polyisocyanate, acetone, 2,4-diaminotoluene and deionized water. After feeding, stir and mix for 2 h to obtain the coating; the amounts of each raw material used are as follows by weight: 30 parts of dehydrated polyether polyol, 50 parts of toluene diisocyanate, 17 parts of modified powder, 9 parts of γ-glycidoxypropyltrimethoxysilane, 9 parts of polymethylene polyphenyl polyisocyanate, 45 parts of acetone, 6 parts of 2,4-diaminotoluene, and 110 parts of deionized water;

[0050] (4) Spray the coating on the surface of the porcelain insulator substrate, and the coating thickness is 500 μm; then heat it to 60 °C in a nitrogen atmosphere and dry for 5 h, and then place it at room temperature for 12 h to obtain the insulator of this comparative example.

[0051] Comparative Example 3

[0052] A preparation method of an insulator for comparison, the steps include:

[0053] (1) Prepare an aqueous solution of cerium nitrate; in the aqueous solution of cerium nitrate, the concentration of cerium nitrate is 25 g / L and the solvent is water; prepare an ethanol solution of tetrabutyl titanate; in the ethanol solution of tetrabutyl titanate, the mass percentage of tetrabutyl titanate is 17% and the solvent is ethanol; prepare an ethanol solution of tetraethoxysilane; in the ethanol solution of tetraethoxysilane, the mass percentage of tetraethoxysilane is 9% and the solvent is ethanol; while stirring, add the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane to the aqueous solution of cerium nitrate at the same time. The volume ratio of the aqueous solution of cerium nitrate, the ethanol solution of tetrabutyl titanate and the ethanol solution of tetraethoxysilane is aqueous solution of cerium nitrate:ethanol solution of tetrabutyl titanate:ethanol solution of tetraethoxysilane = 4:10:6; after the addition is completed, continue to stir the solution for 6 h, then add ammonia water to adjust the pH of the solution to 9. The mass percentage of the solute in the ammonia water is 10%; stir the solution for another 2 h, after the stirring is completed, perform solid-liquid separation, wash the solid phase with deionized water 3 times, dry it at 60 °C for 4 h, and calcine it at 550 °C for 2 h; obtain the doped powder;

[0054] (2) Add the doped powder to Tris-HCl buffer solution (10 mmol / L, pH = 8.5). The amount ratio of the doped powder added to Tris-HCl buffer solution is doped powder:Tris-HCl buffer solution = 9 g:1 L; stir and disperse it for 30 min under ultrasonic environment to obtain a suspension. Stir the suspension, and then add dopamine to the suspension while stirring. The mass ratio of the added dopamine to the doped powder used to prepare the suspension is doped powder:dopamine = 9 g:17 g; after the addition is completed, continue to stir the suspension for 40 h, perform solid-liquid separation, wash the solid phase with deionized water 3 times, and dry it at 60 °C for 4 h to obtain the modified powder of this comparative example;

[0055] (3) Heat toluene diisocyanate in a water bath to 82 °C and keep it warm, then add dehydrated polyether polyol (DJ-12). After the addition is completed, continue to stir at 82 °C for 3 h, then naturally cool to room temperature, add the modified powder, γ-glycidyl ether oxypropyltrimethoxysilane, polymethylene polyphenyl polyisocyanate, acetone, 2,4-diaminotoluene and deionized water. After the addition, stir and mix for 2 h to obtain the coating; the amounts of each raw material used are as follows by weight: 30 parts of dehydrated polyether polyol, 50 parts of toluene diisocyanate, 17 parts of modified powder, 9 parts of γ-glycidyl ether oxypropyltrimethoxysilane, 9 parts of polymethylene polyphenyl polyisocyanate, 45 parts of acetone, 6 parts of 2,4-diaminotoluene, and 110 parts of deionized water;

[0056] (4) Spray the coating on the surface of the porcelain insulator substrate, and the coating thickness is 500 μm; then heat it to 60 °C in a nitrogen atmosphere and dry it for 5 h, and then place it at room temperature for 12 h to obtain the insulator of this comparative example.

[0057] Example 5

[0058] The dropwise method of a contact angle measuring instrument was used to measure the water contact angle of the insulator coatings obtained in the above examples and comparative examples at room temperature. Five specimens were measured in each group, and the average value was taken; then, in accordance with the requirements of Standard GBT9286-2021, the adhesion of the insulator coatings obtained in the above examples and comparative examples was tested, and the results are shown in Table 1.

[0059] As can be seen from Table 1, the porcelain insulator coating prepared by the method of the present invention has good hydrophobicity and scratch resistance, a large water contact angle, is not easily adhered by sewage, has strong anti-pollution ability, and the coating has high strength, strong adhesion, is not easily peeled off, and improves the durability of the porcelain insulator. Comparing Example 3 of the present invention with each comparative example, it can be seen that by adding the modified powder prepared by the present invention, the hydrophobicity and adhesion of the coating can be significantly improved. This is mainly because: the present invention first obtains a cerium-doped titanium-silicon composite oxide powder by a doping thermal decomposition method. By doping cerium to partially replace the position of Ti 4+ ions, it is possible to increase micro-nano structures such as "concave angle structures" or "hierarchical structures" on the particle surface. The curvature radians formed by these structures can generate an upward Laplace pressure, improving the liquid repellency of the material surface and showing a higher contact angle; subsequently, through polydopamine modification, on the one hand, a large number of amino groups are formed on the particle surface, preparing for subsequent modification processes; on the other hand, the particles modified by polydopamine can form a network porous structure in the coating. The porous structure can allow more air to stay in the coating to form an "air cushion layer", improving the hydrophobicity of the coating. At the same time, the network structure improves the strength of the coating, manifested as an increase in scratch resistance. Subsequently, graft modification with 1H,1H,2H,2H-perfluorodecanethiol and mercaptoacetic acid endows the coating surface with more excellent hydrophobicity through perfluoroalkyl chains, and the terminal carboxyl groups improve the dispersibility of the particles and at the same time improve the binding force between the particles and other components in the coating.

[0060] Table 1

[0061] Test group Water contact angle (°) Adhesion test result grade Example 1 150.7 Grade 0 Example 2 151.9 Grade 0 Example 3 152.6 Grade 0 Example 4 152.1 Grade 0 Comparative example 1 149.2 Grade 0 Comparative example 2 147.7 Grade 1 Comparative example 3 146.8 Grade 1

[0062] The technical solutions provided by the present invention have been introduced in detail above. For those of ordinary skill in the art, based on the ideas of the embodiments of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A method for preparing a high-strength anti-fouling porcelain insulator, characterized in that the steps include: (1) preparing an aqueous solution of cerium nitrate; preparing an ethanol solution of n-butyl titanate; preparing an ethanol solution of tetraethoxysilane; adding the ethanol solution of n-butyl titanate and the ethanol solution of tetraethoxysilane to the aqueous solution of cerium nitrate while stirring, stirring the solution for more than 6 hours after the addition is completed, then adding ammonia water to adjust the pH of the solution to 9-10, stirring the solution for more than 2 hours, separating the solid and the liquid after the stirring is completed, washing the solid phase with deionized water for more than 3 times, drying, and calcining at 500-550° C. for more than 2 hours to obtain a doped powder; (2) preparing an ethanol solution of 1H, 1H, 2H, 2H-perfluorodecanethiol in a reactor; adding the doped powder to a Tris-HCl buffer, stirring for more than 30 minutes under an ultrasonic environment to obtain a suspension, stirring the suspension, and then adding dopamine to the suspension under stirring. After the addition is completed, the suspension is continuously stirred for more than 40 hours, solid-liquid separation is performed, the solid phase is washed with deionized water for more than 3 times, and dried. The dried solid phase is immersed in the ethanol solution of 1H, 1H, 2H, 2H-perfluorodecanethiol in the reactor, stirred for more than 10 minutes, and then thioglycolic acid is added under stirring. After the addition, stirring is continued for more than 30 minutes, the reactor is closed, heated to 140±5° C. and kept warm for more than 60 minutes, and then naturally cooled to room temperature, the reactor is opened, solid-liquid separation is performed, the solid phase is washed with ethanol for more than 2 times, and then washed with deionized water for more than 2 times, and dried to obtain a modified powder; (3) heating the toluene diisocyanate in a water bath to 82±2° C. and then adding the dehydrated polyether polyol, stirring at a constant temperature of 82±2° C. for more than 3 h after the addition is completed, and then naturally cooling to room temperature, adding the modified powder, γ-glycidyloxypropyltrimethoxysilane, polymethylene polyphenyl polyisocyanate, acetone, 2,4-diaminotoluene and deionized water, stirring and mixing for more than 2 h after the addition, to obtain a coating; (4) The coating is sprayed on the surface of the porcelain insulator substrate, and then heated to 60±5° C. in a nitrogen atmosphere and dried for more than 5 hours, and then placed at room temperature for more than 12 hours to obtain the high-strength anti-fouling porcelain insulator.

2. The method for preparing a high-strength anti-pollution porcelain insulator according to claim 1, characterized in that: In the step (1), the concentration of cerium nitrate in the aqueous solution is 20-25 g / L, and the solvent is water; the mass percentage of n-butyl titanate in the ethanol solution of n-butyl titanate is 16%-18%, and the solvent is ethanol; the mass percentage of tetraethoxysilane in the ethanol solution of tetraethoxysilane is 8%-10%, and the solvent is ethanol; the volume ratio of the aqueous solution of cerium nitrate, the ethanol solution of n-butyl titanate and the ethanol solution of tetraethoxysilane is cerium nitrate aqueous solution: ethanol solution of n-butyl titanate: ethanol solution of tetraethoxysilane = 3-5:10:4-7.

3. The method for preparing a high-strength anti-pollution porcelain insulator according to claim 1, characterized in that: In the step (1), the mass percentage of the solute in the ammonia water is 10%.

4. The method for preparing a high-strength anti-pollution porcelain insulator according to claim 1, characterized in that: In the step (2), the ratio of the amount of the doping powder added to the Tris-HCl buffer is doping powder: Tris-HCl buffer = 8-10 g: 1 L; the ratio of the added mass of dopamine to the mass of the doping powder added to prepare the suspension is doping powder: dopamine = 8-10 g: 15-18 g.

5. The method for preparing a high-strength anti-pollution porcelain insulator according to claim 1, characterized in that: In the step (2), in the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol, the concentration of 1H,1H,2H,2H-perfluorodecanethiol is 20-30 g / L, and the solvent is ethanol; the dried solid phase and thioglycolic acid are added to the ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol in a ratio of dried solid phase:thioglycolic acid: ethanol solution of 1H,1H,2H,2H-perfluorodecanethiol = 2-3 g:7-9 g:200 mL.

6. The method for preparing a high-strength anti-pollution porcelain insulator according to claim 1, characterized in that: In the step (3), the raw materials used are calculated by weight as follows: 30 parts of dehydrated polyether polyol, 50 parts of toluene diisocyanate, 15-18 parts of modified powder, 8-10 parts of γ-glycidyloxypropyltrimethoxysilane, 8-10 parts of polymethylene polyphenyl polyisocyanate, 40-50 parts of acetone, 5-6 parts of 2,4-diaminotoluene, and 100-120 parts of deionized water.