阅读说明：本技术 制备疏水涂料的方法和疏水涂料 (Method for producing hydrophobic coating and hydrophobic coating ) 是由 林晨 肖鹏飞 于 2019-07-23 设计创作，主要内容包括：本发明公开了制备疏水涂料的方法和疏水涂料。所述方法包括：在40～70℃下向正硅酸乙酯在有机溶剂的溶液中加入氨水进行水解,生成纳米二氧化硅粒子；向水解后的溶液依次添加单氨基烷氧基硅烷、多氨基烷氧基硅烷、草酸溶液,并且升温至80～100℃,进行第一疏水改性处理；向第一疏水改性处理后的溶液添加疏水改性剂和水,进行第二疏水改性处理,制得所述疏水涂料。所述方法制得的涂层对绝缘子表面具有优异的附着力和疏水效果。(The invention discloses a method for preparing a hydrophobic coating and the hydrophobic coating. The method comprises the following steps: adding ammonia water into a solution of tetraethoxysilane in an organic solvent at 40-70 ℃ for hydrolysis to generate nano silicon dioxide particles; sequentially adding monoamino alkoxy silane, polyamino alkoxy silane and oxalic acid solution into the hydrolyzed solution, heating to 80-100 ℃, and performing first hydrophobic modification treatment; and adding a hydrophobic modifier and water into the solution subjected to the first hydrophobic modification treatment, and performing second hydrophobic modification treatment to obtain the hydrophobic coating. The coating prepared by the method has excellent adhesive force and hydrophobic effect on the surface of an insulator.)

1. a method of preparing a hydrophobic coating, comprising the steps of:

Adding ammonia water into a solution of tetraethoxysilane in an organic solvent at 40-70 ℃ for hydrolysis to generate nano silicon dioxide particles;

Sequentially adding monoamino alkoxy silane, polyamino alkoxy silane and oxalic acid solution into the hydrolyzed solution, heating to 80-100 ℃, and performing first hydrophobic modification treatment;

And adding a hydrophobic modifier and water into the solution subjected to the first hydrophobic modification treatment, and performing second hydrophobic modification treatment to obtain the hydrophobic coating.

2. the process according to claim 1 or 2, wherein the monoaminoalkoxysilane is monoaminomethoxysilane or monoaminoethoxysilane and the polyaminoalkoxysilane is polyaminomethoxysilane or polyaminoethoxysilane.

3. The method of claim 1, the hydrophobic modifier is a long chain alkyl trialkoxysilane.

4. The method of claim 3, the long chain alkyltrialkoxysilane being a long chain alkyltrimethoxysilane or a long chain alkyltriethoxysilane.

5. the method of claim 4, the long chain alkyltrialkoxysilane being hexadecyltrimethoxysilane.

6. The method of claim 2, the monoamino alkoxysilane is gamma-aminopropyltriethoxysilane; the polyamino alkoxy silane is gamma-diethylenetriamine propyl methyl dimethoxy silane.

7. the process of claim 1 or 2, the weight ratio of monoamino alkoxysilane to polyaminoalkoxysilane is from 3:7 to 7: 3.

8. The method of claim 1 or 2, wherein the weight ratio of the hydrophobic modifier to the silica nanoparticles is 1: 6.

9. the method of claim 1 or 2, wherein the molar concentration of the oxalic acid solution is 0.5-1 mol/L, and the weight ratio of oxalic acid to silica nanoparticles is 2: 25.

10. a hydrophobic coating prepared according to the method of any one of claims 1 to 9.

Technical Field

The invention relates to a hydrophobic coating and a preparation method thereof, in particular to a super-hydrophobic coating suitable for the surface of an insulator and a preparation method thereof.

Background

after the material is formed into a film, the contact angle is more than 150 degrees and the sliding angle is less than 10 degrees, which is called super-hydrophobic phenomenon. In nature, water drops on the surface of lotus leaves can freely fall, the water strider can freely walk on the water surface, and the surfaces of cicada wings, rice leaves and the like are natural super-hydrophobic phenomena. The lotus leaves are discharged to be sludge without polluting the special self-cleaning effect, so that the lotus leaves are greatly interested in research by scientists and have wide application value in life. The super-hydrophobic surface is covered on the surface of the material, and the effects of water resistance, freeze prevention and corrosion prevention are achieved. The ultra-sparse surface is used on an outdoor antenna, so that accumulated snow can be prevented, and smooth communication signals can be guaranteed; the coating is used on the inner wall of a pipeline for conveying petroleum or textile clothes, and can prevent water and dirt.

The insulator is a frequently used device in industrial production and life power supply. After the surface of the insulator becomes dirty, an electrical breakdown "smudge" phenomenon easily occurs. The existing solution is manual monthly cleaning, and the problem of insulator surface dirt cannot be thoroughly solved by using the existing ordinary RTV anti-pollution flashover coating. The super-hydrophobic technology can be potentially applied to the insulator, and if the adhesion problem can be solved, the pollution flashover problem can be effectively solved, so that the surface of the insulator can be kept clean for a long time. It is urgent to provide a high-adhesion super-hydrophobic coating suitable for use on the surface of an insulator and a preparation method thereof.

At present, the application of super-hydrophobicity on coating has been greatly developed, but a plurality of problems still exist, for example, the cost is high, the requirement on equipment is high, the reaction is harsh, and the long time influences the industrialization of the super-hydrophobic coating, and secondly, from the aspect of practical application, the prepared super-hydrophobic surface has good hydrophobic effect, but the adhesion is poor, the durability is poor, the fine structure of the coating surface is easily damaged, and the super-hydrophobicity of the coating is greatly reduced and even lost. In the prior art, the high adhesive force of the top surface on the stone is ensured through the matching effect of silicon atoms and siloxane, and compared with the condition that the stone is easily bonded with the similar siloxane, the common non-stone base material does not contain the siloxane which is easily bonded, so that the adhesive force of the coating is difficult to improve. The super-hydrophobic coating capable of acting on the surface of a common non-stone base material provided by the invention can play a super-hydrophobic effect when being applied to the surface of an insulator, and meanwhile, the coating is long-acting and wear-resistant and has strong adhesive force.

disclosure of Invention

in view of the above, the main object of the present invention is to provide a method for preparing a hydrophobic coating and a hydrophobic coating prepared by the method, wherein the hydrophobic coating comprises nano-silica powder with high adhesion and super-hydrophobicity as a hydrophobic modifier, and can act on the surface of a common non-stone substrate, especially the surface of an insulator, so as to achieve a super-hydrophobic effect, and the coating has long-term wear resistance and strong adhesion.

According to one aspect of the present invention, there is provided a method of preparing a hydrophobic coating, comprising the steps of:

Adding ammonia water into a solution of tetraethoxysilane in an organic solvent at 40-70 ℃ for hydrolysis to generate nano silicon dioxide particles,

Sequentially adding monoamino alkoxy silane, polyamino alkoxy silane and oxalic acid solution into the hydrolyzed solution, heating to 80-100 ℃, and performing first hydrophobic modification treatment;

And adding a hydrophobic modifier and water into the solution subjected to the first hydrophobic modification treatment, and performing second hydrophobic modification treatment to obtain the hydrophobic coating.

The monoamino alkoxy silane is monoamino methoxy silane or monoamino ethoxy silane, and the polyamino alkoxy silane is polyamino methoxy silane or polyamino ethoxy silane.

The hydrophobic modifier is long-chain alkyl trialkoxysilane.

The long-chain alkyl trialkoxysilane is long-chain alkyl trimethoxysilane or long-chain alkyl triethoxysilane.

The long-chain alkyl trialkoxysilane is hexadecyl trimethoxy silane.

The monoamino alkoxy silane is gamma-aminopropyl triethoxysilane; the polyamino alkoxy silane is gamma-diethylenetriamine propyl methyl dimethoxy silane.

The weight ratio of the monoamino alkoxysilane to the polyaminoalkoxysilane is 3:7 to 7: 3.

The weight ratio of the hydrophobic modifier to the silica nanoparticles is 1: 6.

The molar concentration of the oxalic acid solution is 0.5-1 mol/L, and the mass ratio of oxalic acid to the silicon dioxide nano particles is 2: 25.

According to another aspect of the present invention, there is provided a hydrophobic coating, prepared according to the above method.

therefore, according to the method for preparing the hydrophobic coating, the ethyl orthosilicate is prepared in the ethanol/water mixed solvent to obtain the nano-silica particles containing alkyl and amino, so that the hydrophobic coating containing the nano-silica particles can be self-assembled on the surface of the insulator to form a concave-convex micro-nano structure, and the lotus leaf-like hydrophobic effect is realized. The contact angle of the coating of the hydrophobic coating prepared by the method is 150-160 degrees, and the hydrophobic coating has 90-100% of adhesive force to the surface of the insulator.

Detailed Description

According to the present invention, there is provided a method for preparing a hydrophobic coating, comprising the steps of:

Adding ammonia water into a solution of tetraethoxysilane in an organic solvent at 40-70 ℃ for hydrolysis to generate nano silicon dioxide particles,

sequentially adding monoamino alkoxy silane, polyamino alkoxy silane and oxalic acid solution into the hydrolyzed solution, heating to 80-100 ℃, and performing first hydrophobic modification treatment;

and adding a hydrophobic modifier and water into the solution subjected to the first hydrophobic modification treatment, and performing second hydrophobic modification treatment to obtain the hydrophobic coating.

In the first hydrophobic modification treatment, the monoamino alkoxysilane may be monoamino methoxysilane or monoamino ethoxysilane, and the polyaminoalkoxysilane may be polyaminomethoxysilane or polyaminoethoxysilane. And the weight ratio of the monoamino alkoxysilane to the polyaminoalkoxysilane is 3:7 to 7: 3. The total adding proportion of the monoamino alkoxy silane and the polyamino alkoxy silane is one sixth of the mass of the silicon dioxide nano particles.

Preferably, the monoamino alkoxysilane is γ -aminopropyltriethoxysilane; the polyamino alkoxy silane is gamma-diethylenetriamine propyl methyl dimethoxy silane.

The molar concentration of the oxalic acid solution can be 0.5-1.5 mol/L, preferably 1mol/L, and the mass ratio of oxalic acid to the silica nanoparticles is 2: 25.

And forming the nano silicon dioxide spherical particles with rich amino groups on the surface after the first hydrophobic modification treatment.

Further, in the second hydrophobic modification treatment, the hydrophobic modifier used in the above method may be a long-chain alkyltrialkoxysilane, for example, a long-chain alkyltrimethoxysilane or a long-chain alkyltriethoxysilane, preferably, hexadecyltrimethoxysilane. The hydrophobic modifier may be used in an amount of one sixth of the mass of the silica nanoparticles.

the silicon dioxide particles treated by the second hydrophobic modification, long-chain alkyl trialkoxysilane as a hydrophobic modifier and other silane coupling agents are subjected to synergistic hydrolysis, and are embedded into an alkane chain, so that the silicon dioxide particles have low surface energy, and a good hydrophobic effect is achieved.

Preferably, both the above hydrolysis and hydrophobic modification processes are carried out under stirring, for example at a speed of 400 to 500rpm, preferably 450 rpm. The stirring time is determined according to the progress of the reaction process. Specifically, in the hydrolysis process of the tetraethoxysilane, the stirring time is about 60-90 min, and then ammonia gas is discharged until no ammonia gas taste exists. In the first hydrophobic treatment process, the stirring time is about 30-60 min. In the second hydrophobic treatment process, the stirring time is about 3-6 h.

the above preparation method according to the present invention further comprises placing the mixture in ice water until completely cooled after the second hydrophobic treatment is performed.

The organic solvent may be an alcohol solvent, such as ethanol.

According to one embodiment of the present invention, there is provided a hydrophobic coating, prepared according to the above method.