阅读说明：本技术 一种疏水涂层材料及其制备方法 (Hydrophobic coating material and preparation method thereof ) 是由 鱼银虎 沈妙荣 李若琳 崔海婷 杨斌武 刘赵荣 于 2019-12-02 设计创作，主要内容包括：本发明公开了一种疏水涂层材料及其制备方法,包括以下步骤：正硅酸乙酯与水的体积比为4:1,无水乙醇与正硅酸乙酯的体积比为10:1,通过恒温磁力搅拌器在水解温度50℃-60℃搅拌混合；取正硅酸乙酯、水、四氢呋喃、无水乙醇的体积比为4:1:0.65:10,先把无水乙醇、水和正硅酸乙酯放入烧杯中在恒温磁力搅拌器中50℃-60℃搅拌30min,随后加入四氢呋喃后搅拌15min得透明疏水溶胶,使用提拉膜法制备疏水涂层；薄膜静态接触角θ＝54.5°,不用达到理论接触角θ＝90°的临界点,即可疏水；不需要在使接触角增大而达到疏水的目的；形成溶胶时即可使用于反光镜或玻璃上,不影响视线且溶胶形成凝胶的时间变长,溶胶不用一次性全使用完,可分批使用,节省成本。(The invention discloses a hydrophobic coating material and a preparation method thereof, and the hydrophobic coating material comprises the following steps: stirring and mixing ethyl orthosilicate and water in a volume ratio of 4:1 and absolute ethyl alcohol and ethyl orthosilicate in a volume ratio of 10:1 at a hydrolysis temperature of 50-60 ℃ by a constant-temperature magnetic stirrer; taking ethyl orthosilicate, water, tetrahydrofuran and absolute ethyl alcohol according to the volume ratio of 4:1:0.65:10, firstly putting the absolute ethyl alcohol, the water and the ethyl orthosilicate into a beaker, stirring for 30min at 50-60 ℃ in a constant-temperature magnetic stirrer, then adding the tetrahydrofuran, stirring for 15min to obtain transparent hydrophobic sol, and preparing a hydrophobic coating by using a pulling membrane method; the static contact angle theta of the film is 54.5 degrees, and the film can be hydrophobic without reaching the critical point of the theoretical contact angle theta of 90 degrees; the purpose of hydrophobic property can be achieved without increasing the contact angle; when the sol is formed, the sol can be used on a reflector or glass, the sight is not affected, the time for forming the gel by the sol is prolonged, the sol is not used up at one time, the sol can be used in batches, and the cost is saved.)

1. A hydrophobic coating material, comprising the following ingredients: ethyl orthosilicate, water, absolute ethyl alcohol and tetrahydrofuran.

2. A preparation method of a hydrophobic coating material comprises the following steps:

s1, stirring and mixing the ethyl orthosilicate and the water according to the volume ratio of 4:1 and the volume of the absolute ethyl alcohol being 10 times of that of the ethyl orthosilicate in a constant-temperature magnetic stirrer at the hydrolysis temperature of 50-60 ℃;

s2, stirring for 30-35min, adding tetrahydrofuran, and continuing stirring for 15-20min, wherein the volume ratio of absolute ethyl alcohol to tetrahydrofuran is 15: 1;

s3, placing the glass slide into the sol, slowly pulling out the glass slide, and naturally airing the glass slide to form a film;

s4, drop water on the slide glass, and measure the contact angle using a contact angle measuring instrument.

3. The method for preparing a hydrophobic coating material according to claim 2, wherein: in S1, the ethyl orthosilicate and water are hydrolyzed at 50-60 ℃ to generate silanol and ethanol, then the silanol is condensed, the ethyl orthosilicate is slightly soluble in water, and alcohols or ethers are used as a cosolvent to assist the ethyl orthosilicate and the water in hydrolysis.

4. The method for preparing a hydrophobic coating material according to claim 2, wherein: in S2, the alcohol and ether do not normally undergo any chemical reaction, the tetrahydrofuran does not affect the role of ethanol throughout the reaction, and the tetrahydrofuran and anhydrous ethanol together act to promote hydrolysis.

5. The method for preparing a hydrophobic coating material according to claim 2, wherein: the tetrahydrofuran is ether of five-membered ring, the three-membered ring and the four-membered ring are easy to open at low temperature, the five-membered ring and the six-membered ring are not easy to open, the tetrahydrofuran is difficult to open at the temperature of 50-60 ℃ in the preparation process, and the tetrahydrofuran and the silanol are subjected to substitution reaction.

6. The method for preparing a hydrophobic coating material according to claim 2, wherein: the tetrahydrofuran serves as a co-solvent and a modification modifier in the preparation reaction.

7. The method for preparing a hydrophobic coating material according to claim 2, wherein: the tetrahydrofuran modification is from Si-OH to Si-CH ₃And is converted from a hydrophilic group to a hydrophobic group.

8. The method for preparing a hydrophobic coating material according to claim 2, wherein: and in S2, adding tetrahydrofuran, and continuing stirring for 15-20min, wherein the hydrophobic sol is formed quickly by stirring quickly or slowly, and the preparation time is shortened.

9. The method for preparing a hydrophobic coating material according to claim 2, wherein: the tetrahydrofuran is added in a proper amount, and the excessive tetrahydrofuran is added, so that the sol is formed too fast, and the particle size of the sol is easy to change.

Technical Field

The invention relates to the technical field of hydrophobic coating preparation, in particular to a hydrophobic coating material and a preparation method thereof.

Background

The hydrophobic coating has the functions of dust prevention, self cleaning, corrosion prevention, fog prevention, drag reduction and the like, can be applied to various fields, and to prepare the hydrophobic coating, theoretically, a contact angle theta is more than 90 degrees and generally has certain hydrophobic performance, and the contact angle theta is more than 150 degrees and has super-hydrophobic performance, so that the contact angle theta is 90 degrees and is a hydrophobic critical angle, the contact angle theta is 150 degrees and is a super-hydrophobic critical angle, and the ethyl orthosilicate is a precursor for preparing hydrophobic sol and also can be used for preparing inorganic materials and organic materials which are integrated with high and low temperature resistance, electrical insulation, ozone resistance, radiation resistance, flame resistance, hydrophobicity, corrosion resistance and the like, so the hydrophobic coating can be widely applied to various industries; in addition to tetraethoxysilane to prepare hydrophobic films, methyl silicate (TMOS) can also be used to prepare hydrophobic films, but because it is toxic and difficult to make films, Tetraethoxysilane (TEOS) is easier to prepare hydrophobic sol than methyl silicate (TMOS), so this experiment uses tetraethoxysilane to prepare hydrophobic coatings, and the methods for preparing hydrophobic coatings/materials are mainly as follows: the method for preparing the hydrophobic coating/material comprises a sol-gel method, a chemical etching method, an electrochemical deposition method, a self-loading method, a spraying method and a laser method, but the hydrophobic coating and the hydrophobic material are researched by taking a contact angle theta of more than 90 degrees as a critical point and a contact angle theta of more than 150 degrees, most of the preparation conditions are harsh, the cost is high, large-scale industrial production cannot be realized, and a plurality of limitations exist.

Disclosure of Invention

The invention aims to provide a hydrophobic coating material and a preparation method thereof, so as to solve the problems in the background technology.

In order to achieve the purpose, the invention provides the following technical scheme: a hydrophobic coating material comprising the following ingredients: ethyl orthosilicate, water, absolute ethyl alcohol and tetrahydrofuran.

In addition, the invention also provides a preparation method of the hydrophobic coating material, which comprises the following steps:

s1, stirring and mixing the ethyl orthosilicate and the water in a volume ratio of 4:1, wherein the volume of the absolute ethyl alcohol is 10 times that of the ethyl orthosilicate in a constant-temperature magnetic stirrer at a hydrolysis temperature of 50-60 ℃;

s2, stirring for 30-35min, adding tetrahydrofuran, and continuing stirring for 15-20min, wherein the volume ratio of absolute ethyl alcohol to tetrahydrofuran is 15: 1;

s3, placing the glass slide into the sol, slowly pulling out the glass slide, and naturally airing the glass slide to form a film;

s4, drop water on the slide glass, and measure the contact angle using a contact angle measuring instrument.

As further preferable in the present technical solution: in S1, the ethyl orthosilicate and water are hydrolyzed at 50-60 ℃ to generate silanol and ethanol, then the silanol is condensed, the ethyl orthosilicate is slightly soluble in water, and alcohols or ethers are used as a cosolvent to assist the ethyl orthosilicate and the water in hydrolysis.

As further preferable in the present technical solution: in S2, the alcohol and ether do not normally undergo any chemical reaction, the tetrahydrofuran does not affect the role of ethanol throughout the reaction, and the tetrahydrofuran and anhydrous ethanol together act to promote hydrolysis.

As further preferable in the present technical solution: the tetrahydrofuran is ether of five-membered ring, the three-membered ring and the four-membered ring are easy to open at low temperature, the five-membered ring and the six-membered ring are not easy to open, the tetrahydrofuran is difficult to open at the temperature of 50-60 ℃ in the preparation process, and the tetrahydrofuran and the silanol are subjected to substitution reaction.

As further preferable in the present technical solution: the tetrahydrofuran serves as a co-solvent and a modification modifier in the preparation reaction.

As further preferable in the present technical solution: the tetrahydrofuran modification is from Si-OH to Si-CH ₃And is converted from a hydrophilic group to a hydrophobic group.

As further preferable in the present technical solution: and in S2, adding tetrahydrofuran, and continuing stirring for 15-20min, wherein the hydrophobic sol is formed quickly by stirring quickly or slowly, and the preparation time is shortened.

As further preferable in the present technical solution: the tetrahydrofuran is added in a proper amount, and the excessive tetrahydrofuran is added, so that the sol is formed too fast, and the particle size of the sol is easy to change.

Compared with the prior art, the invention has the beneficial effects that: taking ethyl orthosilicate, water, tetrahydrofuran and absolute ethyl alcohol according to the volume ratio of 4:1:0.65:10, firstly placing the absolute ethyl alcohol, the water and the ethyl orthosilicate into a beaker, stirring for 30min in a constant-temperature magnetic stirrer at 50-60 ℃, then adding the tetrahydrofuran, stirring for 15min to obtain transparent hydrophobic sol, and preparing a hydrophobic coating by using a pulling membrane method; the static contact angle theta of the film is 54.5 degrees, and the film can be hydrophobic without reaching the critical point of the theoretical contact angle theta of 90 degrees; the purpose of hydrophobic property can be achieved without increasing the contact angle; when the sol is formed, the sol can be used on a reflector or glass, the sight is not influenced, the time for forming the gel by the sol is prolonged, the sol is not used up at one time, and the sol can be used in batches, so that the cost is saved; the process is simple, the preparation time is short, and the cost is low.

Drawings

FIG. 1 is a flow diagram of the present invention;

FIG. 2 is a graph of the hydrophobic effect of a sample of the present invention;

FIG. 3 is a diagram of the trajectory of the water droplets of the present invention;

FIG. 4 is a schematic diagram illustrating the calculation of contact angle for a sample according to the present invention;

FIG. 5 is an infrared spectrum of the present invention in a liquid state (sol state);

FIG. 6 is an infrared spectrum in the solid state (gel state) of the present invention;

figure 7 is an XRD diffraction pattern of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.