1. A preparation method of BTA silicon oxide composite spherical superfine powder is characterized by comprising the following steps:

1) mixing 300 parts by mass of deionized water, 0.5-1 part by mass of benzotriazole BTA and 0.6-1 part by mass of cetyl trimethyl ammonium bromide CTAB, uniformly stirring, adding 1-4 parts by mass of sodium hydroxide NaOH, and stirring in a water bath at 78-83 ℃ until the mixture is completely dissolved;

2) adding 5-8 parts by mass of tetraethoxysilane TEOS into 12 parts by mass of absolute ethyl alcohol, and uniformly dispersing to obtain a TEOS ethanol solution;

3) dropwise adding the TEOS ethanol solution obtained in the step 2) into the solution obtained in the step 1) at a speed of 0.4-0.6ml/min under a stirring speed of 400rpm, and stirring for at least 2 hours to obtain a mixed solution of BTA silicon oxide composite spherical superfine powder;

4) separating the mixed solution obtained in the step 3) by using a centrifugal separator, and centrifugally washing the obtained precipitate by using deionized water;

5) and drying the precipitate in an oven at 80-100 ℃ to obtain the BTA silicon oxide composite spherical superfine powder.

2. The method for preparing BTA-silica composite spherical ultrafine powder according to claim 1, wherein in step 1), the purity of BTA is at least 99%, the purity of CTAB is at least 99%, and the purity of NaOH is at least 98%.

3. The method for preparing BTA-silica composite spherical ultrafine powder according to claim 1, wherein in step 2), the purity of TEOS is at least 98%, and the purity of absolute ethanol is at least 99.7%.

4. The method for preparing BTA-silica composite spherical ultrafine powder according to claim 1, wherein in step 4), the speed of the mixed solution is at least 10000rpm and the time is at least 10 min; the precipitate is washed centrifugally with deionized water at a speed of at least 0000rpm for a period of at least 10 min.

Background

BTA is benzotriazole, is a corrosion inhibitor material, is widely applied to metal anticorrosive coatings, but excessive (generally within three thousandths) BTA cannot be directly added into the metal anticorrosive coatings, and excessive addition easily causes the density reduction of the coatings, but causes the corrosion resistance of the coatings to be poor. Generally, BTA is coated in silica microspheres to prepare a slow release capsule, and the slow release capsule is put into a coating to achieve the corrosion inhibition effect, and the membrane layer cannot be damaged due to excessive input of the BTA (for example, in literature, corrosion inhibitor loaded hollow SiO₂Preparation and Properties of microspheres, Proc. silicate Proc. 2020,48(04), P584-588); however, the process for preparing the hollow silica microspheres to support BTA is complicated.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a preparation method of BTA silicon oxide composite spherical superfine powder. According to the preparation method disclosed by the invention, the silicon oxide and the BTA are prepared in a composite manner to obtain the BTA silicon oxide composite particles, so that the instability of a coating caused by direct input into a coating is avoided, the silicon dioxide BTA loading process is simplified, and the application range of the BTA material can be expanded. On the other hand, the spherical BTA composite silicon oxide superfine powder is not easy to agglomerate and is easier to store.

The technical scheme adopted by the invention is as follows:

a method for preparing BTA silicon oxide composite spherical superfine powder comprises the following steps:

1. under the stirring condition of 400r/min, 300 parts by mass of deionized water, 0.5-1 part by mass of benzotriazole BTA and 0.6-1 part by mass of cetyl trimethyl ammonium bromide CTAB are added into a three-neck flask and then uniformly stirred, 1-4 parts by mass of sodium hydroxide NaOH is added, and the mixture is stirred in a water bath at the temperature of 80 ℃ until the mixture is completely dissolved.

2. Adding 5-8 parts by mass of tetraethoxysilane TEOS into 12 parts by mass of absolute ethyl alcohol, and uniformly dispersing to obtain a TEOS ethanol solution;

3. dropping the TEOS ethanol solution obtained in the step (2) into the solution obtained in the step (1) at a speed of 0.5ml/min at a stirring speed of 400rpm, and stirring for 2 hours to obtain a mixed solution of BTA silicon oxide composite spherical superfine powder;

4. separating the mixed solution obtained in the step 3 by using a centrifugal separator (10000rpm, 10min), and centrifugally washing the obtained precipitate twice by using deionized water (10000rpm, 10 min);

5. drying the precipitate in an oven at 80 ℃ for 2h to obtain the BTA silicon oxide composite spherical superfine powder.

In the present invention, in step 1, BTA is 99% from Aladdin industries, Inc.

In the present invention, in step 1, CTAB is 99% of the industrial company alatin.

In the invention, in step 1, NaOH is 98% of Aladdin industries.

In the invention, in step 2, TEOS is 98% of the national drug group chemical reagent company Limited.

In the invention, in the step 2, the absolute ethyl alcohol is 99.7 percent of the chemical reagent of the national drug group.

Compared with the existing preparation method, the invention has the following beneficial effects:

the BTA silicon oxide composite spherical superfine powder has simple preparation process. Because BTA is electrolyte, excessive addition can influence the hydrolytic polymerization process, it is apt to produce and precipitate, the invention through surfactant active (CTAB) add until BTA molecule disperse in precursor solution (ethyl silicate solution) of the silicon oxide evenly after coating, control the proportion of BTA and ethyl silicate at the same time, avoid causing the problem of precipitating fast in the course that ethyl silicate hydrolytic polymerization forms the silicon oxide, participate in ethyl silicate hydrolytic polymerization process and form the compound spherical particle, said method has avoided the hollow silicon oxide microballoons to impregnate the complicated process of loading BTA, and the powder is difficult to agglomerate. According to the method, the silicon oxide and the BTA are compounded to prepare the BTA silicon oxide composite particles, so that the silicon dioxide BTA loading process is simplified, and the application range of the BTA material can be expanded. On the other hand, the spherical BTA composite silicon oxide superfine powder is not easy to agglomerate and is easier to store. And the BTA load rate is higher and reaches 50%.

Drawings

FIG. 1 is a scanning electron microscope (20000 times left and 80000 times right) with different times for BTA silicon oxide composite spherical superfine powder;

FIG. 2 is a transmission electron micrograph (50000 times) of BTA silicon oxide composite spherical ultrafine powder;

FIG. 3 is the differential heat-thermogravimetric curve of BTA silicon oxide composite spherical ultrafine powder.

Detailed Description

The invention is further illustrated by the following specific examples and figures:

example 1

1. Under the stirring condition of 400r/min, 300 parts by mass of deionized water, 0.5 part by mass of benzotriazole BTA and 1 part by mass of hexadecyl trimethyl ammonium bromide CTAB are added into a three-neck flask, then the mixture is uniformly stirred, 1 part by mass of sodium hydroxide NaOH is added, and the mixture is stirred in a water bath at the temperature of 80 ℃ until the mixture is completely dissolved.

2. Adding 8 parts by mass of tetraethoxysilane TEOS into 12 parts by mass of absolute ethyl alcohol, and uniformly dispersing to obtain a TEOS ethanol solution;

3. dropping the TEOS ethanol solution obtained in the step (2) into the solution obtained in the step (1) at a speed of 0.5ml/min at a stirring speed of 400rpm, and stirring for 2 hours to obtain a mixed solution of BTA silicon oxide composite spherical superfine powder;

4. separating the mixed solution obtained in the step 3 by using a centrifugal separator (10000rpm, 10min), and centrifugally washing the obtained precipitate twice by using deionized water (10000rpm, 10 min);

5. drying the precipitate in an oven at 80 ℃ for 2h to obtain the BTA silicon oxide composite spherical superfine powder.

Example 2

1. Under the stirring condition of 400r/min, 300 parts by mass of deionized water, 1 part by mass of benzotriazole BTA and 0.6 part by mass of hexadecyl trimethyl ammonium bromide CTAB are added into a three-neck flask, then the mixture is uniformly stirred, 4 parts by mass of sodium hydroxide NaOH is added, and the mixture is stirred in a water bath at the temperature of 80 ℃ until the mixture is completely dissolved.

2. Adding 5 parts by mass of tetraethoxysilane TEOS into 12 parts by mass of absolute ethyl alcohol, and uniformly dispersing to obtain a TEOS ethanol solution;

3. dropping the TEOS ethanol solution obtained in the step (2) into the solution obtained in the step (1) at a speed of 0.5ml/min at a stirring speed of 400rpm, and stirring for 2 hours to obtain a mixed solution of BTA silicon oxide composite spherical superfine powder;

4. separating the mixed solution obtained in the step 3 by using a centrifugal separator (10000rpm, 10min), and centrifugally washing the obtained precipitate twice by using deionized water (10000rpm, 10 min);

5. drying the precipitate in an oven at 80 ℃ for 2h to obtain the BTA silicon oxide composite spherical superfine powder.

Example 3

1. Under the stirring condition of 400r/min, 300 parts by mass of deionized water, 0.8 part by mass of benzotriazole BTA and 0.9 part by mass of hexadecyl trimethyl ammonium bromide CTAB are added into a three-neck flask, then the mixture is uniformly stirred, 2 parts by mass of sodium hydroxide NaOH is added, and the mixture is stirred in a water bath at the temperature of 80 ℃ until the mixture is completely dissolved.

2. Adding 6 parts by mass of tetraethoxysilane TEOS into 12 parts by mass of absolute ethyl alcohol, and uniformly dispersing to obtain a TEOS ethanol solution;

3. dropping the TEOS ethanol solution obtained in the step (2) into the solution obtained in the step (1) at a speed of 0.5ml/min at a stirring speed of 400rpm, and stirring for 2 hours to obtain a mixed solution of BTA silicon oxide composite spherical superfine powder;

4. separating the mixed solution obtained in the step 3 by using a centrifugal separator (10000rpm, 10min), and centrifugally washing the obtained precipitate twice by using deionized water (10000rpm, 10 min);

5. drying the precipitate in an oven at 80 ℃ for 2h to obtain the BTA silicon oxide composite spherical superfine powder.

FIG. 1 is a scanning electron micrograph of BTA-silica composite spherical ultrafine powder prepared by the method of the present invention, wherein it can be seen that the BTA-silica composite spherical ultrafine powder has a spherical shape and a particle size of about 100 to 150 nm. FIG. 2 is a transmission electron microscope photograph of BTA silica composite spherical ultrafine powder, and it can be seen from FIG. 2 that the BTA silica composite spherical ultrafine powder prepared by the method of the present invention has good dispersibility and is not easy to agglomerate. FIG. 3 is the differential thermal weight curve of BTA-silica composite spherical superfine powder, and it can be seen that the BTA loading rate of the powder is greatly improved at 50%.