CN114561111A

CN114561111A - Preparation method of high-blackness and high-temperature-resistant coating

Info

Publication number: CN114561111A
Application number: CN202210019212.9A
Authority: CN
Inventors: 张昕; 赵娟; 石思宇; 仲莹莹; 赵昆雨; 李辰; 唐源; 杨洋
Original assignee: CASIC Defense Technology Research and Test Center
Current assignee: CASIC Defense Technology Research and Test Center
Priority date: 2022-01-07
Filing date: 2022-01-07
Publication date: 2022-05-31
Anticipated expiration: 2042-01-07
Also published as: CN114561111B

Abstract

The application provides a preparation method of a high-blackness and high-temperature-resistance coating, which comprises the following steps: heating and stirring the dihydric phosphate aqueous solution until the solution is transparent, adding an oxalic acid solution, and cooling to obtain a viscous aluminophosphate adhesive aqueous solution; stirring and mixing ethyl orthosilicate, water, alkaline metal oxide, a coating and a solvent, simultaneously dropwise adding a supplement liquid to obtain a mixed liquid, and continuously stirring, aging, filtering, washing and drying the mixed liquid to obtain a coating curing agent; adding graphite powder and ferric oxide powder into the coated curing agent, and uniformly stirring to obtain a filled curing agent; and stirring and mixing the filling curing agent and the aluminum phosphate adhesive aqueous solution to obtain the high-blackness high-temperature-resistant coating. The coating prepared by the application has the advantages of short curing time, high blackness, strong temperature resistance, small blackness change at the high temperature of 1200 ℃, difficult fading, no smoke, no pungent smell during coating, safety and environmental protection.

Description

Preparation method of high-blackness and high-temperature-resistant coating

Technical Field

The application relates to the technical field of paint preparation, in particular to a preparation method of a high-blackness and high-temperature-resistance paint.

Background

In the heating process of an aircraft heat insulation ground test and a boiler heating transmission and distribution system, a heat transfer surface needs to be treated, and a black heat absorption coating is usually coated on the heat transfer surface to control heat flow so as to enable the temperature of a sample to respond quickly, avoid the low heat transfer efficiency and consume a large amount of energy, and achieve the purpose of saving energy. The coating needs to have good high-temperature resistance, avoids the blackness from being greatly reduced due to high-temperature volatilization, simultaneously avoids ablation smoke from blocking the stability of radiation heat energy, and even can generate open fire when the smoke is serious to form a hazard source.

At present, the self-drying organic high-temperature resistant spray paint composed of an ethyl acetate film-forming agent, a heat-resistant pigment, an auxiliary agent, a solvent and the like is commonly used for absorbing irradiation energy. In practical application, the blackness of the paint meets the conditions, but the paint is easy to fade and generate smoke under the high-temperature condition of about 900 ℃, the paint has strong smell during spraying, the light transmittance is strong after one-time spraying, and multiple times of spraying are needed. Therefore, a coating with strong adhesion, high blackness, high temperature resistance, safety and environmental protection is needed to reduce the loss of irradiation energy.

Disclosure of Invention

In view of the above, the present application aims to provide a method for preparing a high-blackness and high-temperature-resistant coating.

Based on the above purpose, the present application provides a preparation method of a high-blackness and high-temperature-resistant coating, comprising:

heating and stirring the dihydric phosphate aqueous solution until the solution is transparent, adding oxalic acid solution, and cooling to obtain viscous aluminophosphate adhesive aqueous solution;

stirring and mixing ethyl orthosilicate, water, alkaline metal oxide, a coating and a solvent, simultaneously dropwise adding a supplement liquid to obtain a mixed liquid, and continuously stirring, aging, filtering, washing and drying the mixed liquid to obtain a coating curing agent;

adding graphite powder and ferric oxide powder into the coated curing agent, and uniformly stirring to obtain a filled curing agent;

and stirring and mixing the filling curing agent and the aluminum phosphate adhesive aqueous solution to obtain the high-blackness high-temperature-resistant coating.

Further, the heating and stirring of the dihydrogen phosphate aqueous solution until the solution is transparent comprises: dissolving dihydrogen phosphate in water, heating at 100 deg.C under stirring to dissolve, heating to 150 deg.C under stirring to obtain milky solution, and heating to obtain transparent solution.

Further, the mass ratio of the ethyl orthosilicate, the water, the alkaline metal oxide, the coating and the solvent is as follows: 20-50: 20-30: 10-30: 20-50: 1 to 5.

Further, the mass ratio of the tetraethoxysilane to the water to the alkali metal oxide to the coating to the solvent is as follows: 30-40: 23-28: 15-25: 20-40: 2 to 4.

Further, the mass ratio of the ethyl orthosilicate, the water, the alkaline metal oxide, the coating and the solvent is as follows: 35: 25: 20: 30: 3.

further, the mass ratio of the coating curing agent to the graphite powder to the iron oxide powder is as follows: 5-15: 0.7-5: 20 to 60.

Further, the mass ratio of the coating curing agent to the graphite powder to the iron oxide powder is as follows: 8-13: 1-4: 30 to 50.

Further, the mass ratio of the coating curing agent to the graphite powder to the iron oxide powder is as follows: 14: 2.4: 40.

further, the mass ratio of the filling curing agent to the aluminum phosphate adhesive aqueous solution is as follows: 2.5-4: 1.

further, the mass ratio of the filling curing agent to the aluminum phosphate adhesive aqueous solution is as follows: 3.2: 1.

further, the mass ratio of the dihydrogen phosphate aqueous solution to the oxalic acid solution is: 30-50: 1.

further, the mass ratio of the dihydrogen phosphate aqueous solution to the oxalic acid solution is: 40: 1.

further, the heating and stirring temperature is 140-160 ℃.

Further, the temperature of the heating and stirring was 150 ℃.

Further, the dihydrogen phosphate is aluminum dihydrogen phosphate.

Further, the basic metal oxide is one or more of magnesium oxide, chromium oxide and iron oxide; the coating is graphite powder.

Further, the solvent is a mixture of a cosolvent and ammonia water, and the cosolvent is one or more of ethanol, isopropanol, formamide, pyridine, acetone and methanol.

Further, the supplementary liquid is a mixed solution of ethanol and ethyl orthosilicate.

Further, the volume ratio of ethanol to ethyl orthosilicate in the supplementary liquid is 1: 1.

wherein the replenisher is used for complementing the mass loss of the tetraethoxysilane caused by hydrolysis.

The aluminum phosphate adhesive aqueous solution is used as a substrate in the preparation of the coating and plays a role in adhesion, so that the prepared coating can be well adhered to a heat transfer surface. The oxalic acid solution is added to prevent the dehydration and recrystallization of the phosphate.

Wherein, graphite powder is used for coating the alkaline metal oxide, and SiO generated by hydrolyzing tetraethoxysilane₂As a connecting framework between the graphite powder and the alkaline metal oxide, the graphite powder can be better coated on the outer wall of the alkaline metal oxide.

Because the activity of the alkali metal oxide is strong, and the crosslinking speed of the alkali metal oxide and the aluminum phosphate adhesive is too high, the curing speed is too high, and finally, a loose and porous gelatinous structure is formed on the surface of the coating, even a film cannot be formed. Therefore, it is necessary to coat the basic metal oxide with graphite powder to form a coated curing agent, which can delay the release of the basic metal oxide, inhibit the activity of the curing agent, and improve the blackness of the coating. The alkaline metal oxide coated by the graphite has non-uniformity and non-compactness, and the aluminum phosphate adhesive can slowly enter the alkaline metal oxide through the gaps and the defects of the coating layer to delay the reaction, so that the curing temperature and the curing time of the coating are remarkably reduced, and the normal-temperature curing is realized.

Wherein, iron oxide powder is added into the coating curing agent to play a role in improving the thermal conductivity and increasing the blackness of the coating. In addition, the acidic aqueous solution of the aluminum phosphate adhesive can corrode ferric oxide to generate insoluble ferric phosphate to cause the surface of ferric oxide to be phosphorized, and meanwhile, aluminum ions in aluminum dihydrogen phosphate can undergo hydrolytic polycondensation to form a film together with the ferric phosphate generated after the surface of ferric oxide is phosphorized, so that the curing time is shortened, and the normal-temperature curing is further accelerated.

The graphite powder and the iron oxide powder can be combined with a coating curing agent or an aqueous solution substrate of an aluminum phosphate adhesive while playing a role of high absorption of irradiation energy, so that the curing is accelerated, and the finally formed coating has good adhesiveness and high blackness, is free from odor during coating, is environment-friendly and safe, does not generate smoke, and reduces the irradiation heat attenuation.

From the above, the paint prepared by the preparation method of the high-blackness high-temperature-resistant paint provided by the application has the advantages of short curing time, high blackness, strong temperature resistance, small blackness change at a high temperature of 1200 ℃, difficulty in fading, no smoke, no pungent smell generated during coating, safety and environmental friendliness.

Drawings

In order to more clearly illustrate the technical solutions in the present application or the related art, the drawings needed to be used in the description of the embodiments or the related art will be briefly introduced below, and it is obvious that the drawings in the following description are only embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a photograph of the coated curing agent prepared in comparative example 6 observed under a body microscope;

FIG. 2 is a photograph of the coated curing agent prepared in example 5 observed under a stereomicroscope;

FIG. 3 is a pictorial representation of an adhesion test for the coating prepared in example 5;

FIG. 4 is a physical representation of the temperature resistance test prepared in example 5.

Detailed Description

For the purpose of promoting a better understanding of the objects, aspects and advantages of the present disclosure, reference is made to the following detailed description taken in conjunction with the accompanying drawings.

It is to be noted that, unless otherwise defined, technical terms used in the following examples have the same meanings as commonly understood by one of ordinary skill in the art to which the present invention belongs. The test reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the experimental methods are conventional methods unless otherwise specified.

Example 1

The application provides a preparation method of a high-blackness and high-temperature-resistance coating, which comprises the following steps:

(1) 100g of aluminum dihydrogen phosphate is dissolved in 100g of water, and the solution is heated and stirred at 100 ℃ until the aluminum dihydrogen phosphate is dissolved, so that an aluminum dihydrogen phosphate aqueous solution is obtained, and the solution is milky white. Continuing heating, stirring and heating to 140 ℃ until the solution becomes transparent, adding 4g of oxalic acid solution, and cooling to obtain a viscous aluminum phosphate adhesive aqueous solution;

(2) stirring and mixing 20g of ethyl orthosilicate, 20g of water, 10g of magnesium oxide, 20g of graphite powder, 1g of mixed solvent of ethanol and ammonia water, and simultaneously dropwise adding a solvent with a volume ratio of 1: 1 to obtain a mixed solution, and continuously stirring, aging, filtering, washing and drying the mixed solution to obtain a coating curing agent;

(3) adding 0.7g of graphite powder and 20g of iron oxide powder into 5g of the coating curing agent, and uniformly stirring to obtain 25.7g of filling curing agent;

(4) and (3) stirring and mixing 25g of the filling curing agent obtained in the step (3) and 10g of the aqueous solution of the aluminum phosphate adhesive obtained in the step (1) to obtain the high-blackness and high-temperature-resistant coating.

Example 2

(1) 100g of aluminum dihydrogen phosphate is dissolved in 100g of water, and the solution is heated and stirred at 100 ℃ until the aluminum dihydrogen phosphate is dissolved, so that an aluminum dihydrogen phosphate aqueous solution is obtained, and the solution is milky white. Continuing heating, stirring and heating to 160 ℃ until the solution becomes transparent, adding 6.6g of oxalic acid solution, and cooling to obtain viscous aluminum phosphate adhesive aqueous solution;

(2) stirring and mixing 50g of ethyl orthosilicate, 30g of water, 30g of chromium oxide, 50g of graphite powder, 5g of isopropanol and a mixed solvent of ammonia water, and simultaneously dropwise adding a solvent with a volume ratio of 1: 1 to obtain a mixed solution, and continuously stirring, aging, filtering, washing and drying the mixed solution to obtain a coating curing agent;

(3) adding 5g of graphite powder and 60g of iron oxide powder into 15g of the coated curing agent, and uniformly stirring to obtain 80g of filling curing agent;

(4) and (2) stirring and mixing 80g of the filling curing agent obtained in the step (3) and 20g of the aluminophosphate adhesive aqueous solution obtained in the step (1) to obtain the high-blackness high-temperature-resistant coating.

Example 3

(1) 100g of aluminum dihydrogen phosphate is dissolved in 100g of water, and the solution is heated and stirred at 100 ℃ until the aluminum dihydrogen phosphate is dissolved, so that an aluminum dihydrogen phosphate aqueous solution is obtained, and the solution is milky white. Continuing heating, stirring and heating to 150 ℃ until the solution becomes transparent, adding 5g of oxalic acid solution, and cooling to obtain a viscous aqueous solution of the aluminum phosphate adhesive;

(2) stirring and mixing 30g of tetraethoxysilane, 23g of water, 15g of ferric oxide, 20g of graphite powder, 2g of formamide, pyridine and mixed solvent of ammonia water, and simultaneously dropwise adding a solvent mixture with a volume ratio of 1: 1 to obtain a mixed solution, and continuously stirring, aging, filtering, washing and drying the mixed solution to obtain a coating curing agent;

(3) adding 1g of graphite powder and 30g of iron oxide powder into 8g of the coating curing agent, and uniformly stirring to obtain 39g of filling curing agent;

(4) and (3) stirring and mixing 39g of the filling curing agent obtained in the step (3) and 12g of the aqueous solution of the aluminum phosphate adhesive obtained in the step (1) to obtain the high-blackness and high-temperature-resistant coating.

Example 4

(1) 100g of aluminum dihydrogen phosphate was dissolved in 100g of water, and the mixture was heated and stirred at 100 ℃ to dissolve it, thereby obtaining an aqueous aluminum dihydrogen phosphate solution which was milky white. Continuing heating, stirring and heating to 150 ℃ until the solution becomes transparent, adding 5g of oxalic acid solution, and cooling to obtain a viscous aqueous solution of the aluminum phosphate adhesive;

(2) stirring and mixing 40g of ethyl orthosilicate, 28g of water, 25g of a mixture of magnesium oxide and chromium oxide, 40g of graphite powder, 4g of ethanol, isopropanol and ammonia water, and simultaneously dropwise adding a solvent mixture with a volume ratio of 1: 1 to obtain a mixed solution, and continuously stirring, aging, filtering, washing and drying the mixed solution to obtain a coating curing agent;

(3) adding 4g of graphite powder and 50g of iron oxide powder into 13g of the coating curing agent, and uniformly stirring to obtain 67g of filling curing agent;

(4) and (3) stirring and mixing 67g of the filling curing agent obtained in the step (3) and 21g of the aqueous solution of the aluminum phosphate adhesive obtained in the step (1) to obtain the high-blackness and high-temperature-resistant coating.

Example 5

(2) stirring and mixing 35g of tetraethoxysilane, 25g of water, 20g of magnesium oxide, 30g of graphite powder, 3g of mixed solvent of ethanol and ammonia water, and simultaneously dropwise adding a solvent mixture with the volume ratio of 1: 1 to obtain a mixed solution, and continuously stirring, aging, filtering, washing and drying the mixed solution to obtain a coating curing agent;

(3) adding 2.4g of graphite powder and 40g of iron oxide powder into 14g of the coating curing agent, and uniformly stirring to obtain 56.4g of filling curing agent;

(4) and (3) stirring and mixing 56g of the filling curing agent obtained in the step (3) and 17.5g of the aqueous solution of the aluminum phosphate adhesive obtained in the step (1) to obtain the high-blackness and high-temperature-resistant coating.

Comparative example 1

The preparation method of the high-blackness and high-temperature-resistance coating is different from the embodiment 5 in that the mass of the aluminum phosphate adhesive aqueous solution added in the step (4) is 28g, and the mass of the rest preparation steps and the mass of each component are the same as the embodiment 5.

Comparative example 2

The preparation method of the high-blackness and high-temperature-resistance coating is different from the embodiment 5 in that the mass of the aluminum phosphate adhesive aqueous solution added in the step (4) is 11.2g, and the mass of the rest preparation steps and the mass of each component are the same as the embodiment 5.

Comparative example 3

The preparation method of the high-blackness and high-temperature-resistance coating is different from the embodiment 5 in that the mass of the iron oxide powder added in the step (3) is 10g, and the rest of the preparation steps and the mass of each component are the same as the embodiment 5.

Comparative example 4

The preparation method of the high-blackness and high-temperature-resistance coating is different from the embodiment 5 in that the mass of the iron oxide powder added in the step (3) is 70g, and the rest of the preparation steps and the mass of each component are the same as the embodiment 5.

Comparative example 5

The preparation method of the high-blackness and high-temperature-resistance coating is different from the embodiment 5 in that no iron oxide powder is added in the step (3), and the rest preparation steps and the mass of each component are the same as the embodiment 5.

Comparative example 6

The preparation method of the high-blackness and high-temperature-resistance coating is different from that of the example 5 in that no graphite powder is added in the step (2), and the rest preparation steps and the mass of each component are the same as those of the example 5.

Comparative example 7

The preparation method of the high-blackness and high-temperature-resistance coating is different from the embodiment 5 in that ethyl acetate is used for replacing a mixed solvent of ethanol and ammonia water in the step (2), and the rest preparation steps and the mass of each component are the same as the embodiment 5.

Comparative example 8

A preparation method of a high-blackness high-temperature-resistance coating is different from that of example 5 in that ethanol is used in the step (2) to replace a mixed solvent of ethanol and ammonia water, and the rest of preparation steps and the quality of each component are the same as those of example 5.

The coatings prepared in examples 1 to 5 and comparative examples 1 to 8 were applied to the surface of the sample, and the coatings were cured. The cure time of the coating was recorded and the surface of the cured coating was observed, as detailed in table 1 below.

TABLE 1 test data tabulation of example 5 and comparative examples 1 to 8

As shown in table 1 above, when the coating prepared in examples 1 to 5 is coated on the surface of a sample, the curing time of the coating is 25 to 35min, and the coating formed after the coating is cured has a smooth surface, uniform color, no delamination or cracking, and good coating effect.

The coating prepared in comparative example 1 was coated on the surface of the sample, and the curing time of the coating was 90 min. Compared with example 5, the mass of the aqueous solution of the aluminum phosphate adhesive added in step (4) of comparative example 1 is higher, so that the prepared coating is thinner and has better fluidity, so that the coating is difficult to coat on the surface of a sample, the curing time after coating is increased, and the time cost for using the coating is increased.

The coating prepared in comparative example 2 was coated on the surface of a sample, the curing time of the coating was 15min, and the surface of the coating formed after the coating was cured was not smooth. Compared with example 5, the quality of the aqueous solution of the aluminum phosphate adhesive added in step (4) of comparative example 1 is low, so that the prepared coating has poor adhesion and is difficult to uniformly coat on the surface of a sample; meanwhile, the coating is viscous, so that the curing time of the coating is short, the surface of the coated coating is not smooth and the coated coating is easy to fall off.

The coating prepared in comparative example 3 was coated on the surface of the sample, and the curing time of the coating was 120 min. The iron oxide powder added in step (3) of comparative example 3 was lower in mass than example 5. Because the acidic aqueous solution of the aluminum phosphate adhesive can corrode ferric oxide to generate insoluble ferric phosphate, and meanwhile, aluminum ions in aluminum dihydrogen phosphate can be subjected to hydrolytic polycondensation to form a film together with the ferric phosphate generated by corroding the surface of the ferric oxide, the curing time is shortened. Since the addition amount of iron oxide was reduced in comparative example 3, less iron phosphate, which is an insoluble substance, was generated, so that the curing time was increased, and the time cost for using the coating was increased.

The coating prepared in comparative example 4 was coated on the surface of the sample, and the curing time of the coating was 10 min. Compared with example 5, the iron oxide powder added in step (3) of comparative example 4 has higher quality, resulting in more iron phosphate, which is an insoluble substance, and greatly reduced curing time. However, the addition of too much iron oxide powder causes too much insoluble substances in the prepared coating, and finally causes the surface of the coating formed after the coating is cured to be granular and the coating to be uneven.

The coating prepared in comparative example 5 was coated on the surface of the sample, and the curing time of the coating was 240 min. Compared with example 5, in the step (3) of comparative example 5, iron oxide powder is not added, so that indissolvable substance iron phosphate cannot be generated, the curing time is greatly increased, and the time cost for using the coating is increased.

The coating obtained in comparative example 6 was coated on the surface of the sample, and the curing time of the coating was 9 min. Compared with the embodiment 5, in the step (2) of the comparative example 6, the graphite powder is not added, so that the alkaline metal oxide is not coated by the graphite powder, the activity of the alkaline metal oxide is not inhibited, the activity of the alkaline metal oxide is stronger, the crosslinking speed with the aluminum phosphate adhesive is too high, the curing speed is too high, a loose and porous gelatinous structure is formed on the surface of the coating, and the coating at a part of the position is not completely cured.

Referring to FIGS. 1 and 2, FIG. 1 is a photograph of the coated curing agent prepared in comparative example 6 observed under a microscope, and it can be seen that there are many white spots in FIG. 1, which are locations where the basic metal oxide magnesia aggregates; FIG. 2 is a photograph of the coated curing agent prepared in example 5 observed under a stereomicroscope, and it can be seen that there are no obvious white spots and no obvious boundaries in FIG. 2, demonstrating that the magnesium oxide in example 5 is coated with graphite powder and cannot be aggregated to generate white spots.

The coating obtained in comparative example 7 was applied to the surface of a sample, and the curing time of the coating was 20 min. Compared with example 5, in step (2) of comparative example 7, ethyl acetate is used instead of a mixed solvent of ethanol and ammonia water, and an organic solvent ethyl acetate is used as a solvent, so that the volatilization of the coating can be accelerated, the film forming speed is increased, and the curing time is reduced, but the lack of ammonia water causes poor solubility of each component in the coating, the components are difficult to uniformly mix, and finally, a coating formed after the coating is cured has an obvious layering phenomenon, and cracks are generated on the surface of the coating.

The coating obtained in comparative example 8 was applied to the surface of a sample, and the curing time of the coating was 22 min. Compared with example 5, in step (2) of comparative example 7, ethanol is used instead of a mixed solvent of ethanol and ammonia water, and ammonia water is not added, so that the solubility of each component in the coating is poor, the components are difficult to uniformly mix, and finally, a coating formed after the coating is cured has an obvious layering phenomenon, and the surface color of the coating is not uniform.

Further, the coatings prepared in example 5 and comparative examples 1 to 8 were applied to the surface of a sample, and after the coatings were cured, the coatings or the coatings formed after the coatings were cured were subjected to the following performance tests.

(1) Adhesion test

The adhesion of the coating is characterized by reference to the GB/T9286-1998 test for the marking of paint and varnish on a glass plate, the coating is applied to the glass plate, the coating is cut in a rectangular grid pattern and penetrates into the glass plate to assess the resistance of the coating to detachment from the glass plate and to observe whether the coating has detached. The observation results are detailed in the following table 2 and fig. 3.

(2) Temperature resistance test

Burning the surface of the coating for 3min by using an alcohol blast lamp (the temperature is about 1000 ℃ generally), and observing the surface state of the coating. The observation results are shown in table 2 below and fig. 4. And coating the coating on the crucible, calcining the crucible coated with the coating at the high temperature of 1200 ℃ for 5min by using a muffle furnace, and measuring the mass loss of the crucible before and after calcination.

The results show that in example 5, the mass loss part is substantially the same as the mass of the solvent, and it is proved that the mass loss of the coating is only solvent volatilization under the high-temperature calcination at 1200 ℃, the coating has no mass loss, and the coating can resist the high temperature of 1200 ℃, and has very good high-temperature resistance.

(3) Blackness test

The surface of the coating is burned for 3min by using an alcohol blast lamp (the temperature is generally about 1000 ℃), and the blackness of the coating on the surface of the crucible is tested by using a blackness meter with a range of 0-4.5, and the test data are detailed in the following table 2.

Table 2 performance test data list

Comparative examples 1 to 4 only change the mass ratio of each component in the preparation process without changing the kind of the components used in the preparation process, and compared to example 5, the change of the mass ratio does not cause a very significant difference in the presence or absence of smoke during firing at 1000 c of the paint, the surface condition of the coating after firing at 1000 c, the blackness before and after firing, and the resistance, and thus table 2 above only lists the data relating to example 5 and comparative examples 5 to 8.

Referring to table 2, comparative example 5, in comparison with example 5, in which no iron oxide powder was added during the preparation, resulted in a significant decrease in the blackness of the prepared coating (3.02) so that the blackness requirement of the daily coating could not be satisfied.

Compared with example 5, comparative example 6 does not add graphite powder in the preparation process, so that a loose and porous gelatinous structure is formed on the surface of the prepared coating, and a part of the coating is not completely cured, so that the coating slips off frequently in the cutting process, the resistance of the coating is poor, and the blackness of the coating is reduced.

Compared with the comparative example 5, the organic solvents of ethyl acetate and ethanol are used in the comparative examples 7 and 8 to replace the mixed solvent of ethanol and ammonia water in the example 5, so that the solubility of each component in the coating is poor, the cutting edge of the coating is rough, the coating has more cracks, a large amount of smoke is generated in the process of high-temperature ignition at 1000 ℃, and the blackness after ignition is obviously reduced.

In conclusion, the paint prepared by the preparation method of the high-blackness and high-temperature-resistance paint provided by the application has the advantages of short curing time, high blackness, strong temperature resistance, small blackness change at a high temperature of 1200 ℃, difficulty in fading, no smoke, no pungent smell generated during coating, safety and environmental protection.

Those of ordinary skill in the art will understand that: the discussion of any embodiment above is meant to be exemplary only, and is not intended to intimate that the scope of the disclosure, including the claims, is limited to these examples; within the idea of the present disclosure, also technical features in the above embodiments or in different embodiments may be combined, steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present disclosure as described above, which are not provided in detail for the sake of brevity.

The disclosed embodiments are intended to embrace all such alternatives, modifications and variances which fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalents, improvements, and the like that may be made within the spirit and principles of the embodiments of the disclosure are intended to be included within the scope of the disclosure.

Claims

1. A preparation method of a high-blackness and high-temperature-resistance coating is characterized by comprising the following steps:

2. The preparation method according to claim 1, wherein the mass ratio of the tetraethoxysilane, the water, the alkali metal oxide, the coating and the solvent is as follows: 20-50: 20-30: 10-30: 20-50: 1 to 5.

3. The preparation method according to claim 1, wherein the coating curing agent, the graphite powder and the iron oxide powder are mixed in a mass ratio of: 5-15: 0.7-5: 20 to 60.

4. The preparation method of claim 1, wherein the mass ratio of the filling curing agent to the aluminum phosphate adhesive aqueous solution is as follows: 2.5-4: 1.

5. the method according to claim 1, wherein the mass ratio of the dihydrogen phosphate aqueous solution to the oxalic acid solution is: 30-50: 1.

6. the method according to claim 1, wherein the temperature of the heating and stirring is 140 to 160 ℃.

7. The method according to claim 1, wherein the dihydrogen phosphate is aluminum dihydrogen phosphate.

8. The preparation method according to claim 1, wherein the basic metal oxide is one or more of magnesium oxide, chromium oxide, and iron oxide; the coating is graphite powder.

9. The preparation method of claim 1, wherein the solvent is a mixture of a cosolvent and ammonia water, and the cosolvent is one or more of ethanol, isopropanol, formamide, pyridine, acetone and methanol.

10. The method according to claim 1, wherein the replenishment solution is a mixed solution of ethanol and ethyl orthosilicate.