CN112266649A

CN112266649A - Cyan material and preparation method thereof, near-infrared high-reflection blue coating and preparation method thereof

Info

Publication number: CN112266649A
Application number: CN202011149995.XA
Authority: CN
Inventors: 祖梅; 吕呈龙; 程海峰
Original assignee: National University of Defense Technology
Current assignee: National University of Defense Technology
Priority date: 2020-10-23
Filing date: 2020-10-23
Publication date: 2021-01-26
Anticipated expiration: 2040-10-23
Also published as: CN112266649B

Abstract

The invention discloses a green material which comprises the following raw materials in parts by weight: 30-40 parts of a 4A molecular sieve; 40-50 parts of sulfur powder; 5-10 parts of quartz powder; 4-10 parts of rosin; 4-10 parts of sodium carbonate. The invention also discloses a preparation method of the ultramarine material, which comprises the following steps: (1) mixing and compacting a 4A molecular sieve, quartz powder, sulfur powder, anhydrous sodium carbonate and rosin to obtain a mixture; (2) and performing first-stage low-temperature heat treatment and second-stage high-temperature heat treatment on the mixture, and then purifying to obtain the ultramarine blue material. The invention also discloses a near-infrared high-reflection blue coating and a preparation method thereof. The ultramarine blue material synthesized by the method has high reflectivity in a near infrared band, can reflect 75-90% of the energy of the sun in the near infrared band, can reduce the absorption of the coating to the solar heat to the maximum extent, and achieves the purpose of reducing energy consumption.

Description

Cyan material and preparation method thereof, near-infrared high-reflection blue coating and preparation method thereof

Technical Field

The invention belongs to the field of materials, and particularly relates to a pigment, a preparation method of the pigment, a coating and a preparation method of the coating.

Background

To meet the aesthetic needs of people, more and more architectural and equipment surfaces are painted with colored coatings. However, in hot summer, the surface of the building is heated up due to the action of solar radiation, and the environmental comfort of indoor workers is reduced. The common solution is to use a cooling device such as an air conditioner to cool, but this will cause a large amount of energy consumption. The energy of solar radiation is 52% distributed in the near infrared band (780-2500 nm). For a colored coating, if the energy of the near infrared band can be reflected to the maximum extent, the absorption of the building to the solar energy can be effectively reduced, and the energy consumption is reduced.

As a widely used coating, a blue coating is related to a material with high reflectivity in a near infrared band, but the problems of low reflectivity, complex preparation process, high cost and the like generally exist, and the blue coating is not suitable for large-scale popularization and application.

Disclosure of Invention

The invention aims to overcome the defects and shortcomings in the background technology and provide an ultramarine blue material with high reflectivity in a near-infrared band, a preparation method thereof, a near-infrared high-reflection blue coating and a preparation method thereof, wherein the ultramarine blue material is simple in preparation process and low in cost. In order to solve the technical problems, the technical scheme provided by the invention is as follows:

an ultramarine material for preparing a near-infrared high-reflection blue coating comprises the following raw materials in parts by weight:

in the ultramarine material, preferably, the mass ratio of the sulfur powder to the anhydrous sodium carbonate is 1: (0.1-0.2), wherein the mass ratio of the 4A molecular sieve to the quartz powder is (4-8): 1. in the invention, the ratio of sodium carbonate to S is the key for preparing the ultramarine material, and preferably, the mass ratio of the sulfur powder to the anhydrous sodium carbonate is 1: (0.1-0.2). In the invention, in order to achieve the purpose of high reflectivity of the ultramarine blue material in a near infrared band, quartz powder is required to be added to regulate and control the components, the size and the morphology of the ultramarine blue material. Controlling the mass ratio of the 4A molecular sieve to the quartz powder to be (4-8): 1, the raw materials of the ultramarine blue material can meet the requirements.

In the above ultramarine material, preferably, the ultramarine material has an ellipsoidal shape and a size distribution of 1 to 3 μm.

The crystal grain shape of the ultramarine blue material is regular and the size distribution range is narrow, and compared with the conventional commercial ultramarine blue material, the reflectivity of the ultramarine blue material in a near infrared band is obviously improved.

As a general technical concept, the present invention also provides a method for preparing the ultramarine material, comprising the steps of:

(1) mixing and compacting a 4A molecular sieve, quartz powder, sulfur powder, anhydrous sodium carbonate and rosin to obtain a mixture;

(2) and (2) carrying out first-stage low-temperature heat treatment and second-stage high-temperature heat treatment on the mixture obtained in the step (1), and then cooling and purifying to obtain the ultramarine blue material.

In the preparation method, preferably, the temperature of the first-stage low-temperature heat treatment is 400-; the temperature of the two-stage high-temperature heat treatment is 950-. The two-stage heat treatment process is favorable for more complete reaction of reaction raw materials, the product is more pure, the impurity content is less, the obtained ultramarine materials are ellipsoidal, the size distribution is narrow, and the reflectivity of the ultramarine materials in a near infrared band is higher. The temperature of the two-stage heat treatment needs to be strictly controlled, and particularly, when the two-stage high-temperature heat treatment is carried out, the reflectivity of the product in a near infrared band is greatly influenced by overhigh or overlow temperature.

In the preparation method, preferably, a sodium sulfite boiling solution is used for purification during purification, and the mass ratio of sodium sulfite to deionized water in the sodium sulfite boiling solution is 1: (30-50). In the present invention, further purification is required due to the presence of more impurities in the primary product. The boiling liquid of sodium sulfite can achieve better purification effect.

As a general technical concept, the invention also provides a near-infrared high-reflection blue coating, which mainly comprises an ellipsoidal ultramarine material and a film forming agent, and the reflectivity of the blue coating in a near-infrared band is 75-90%. The ellipsoidal ultramarine material is the ultramarine material described above. The reflectivity of the existing conventional blue coating in a near-infrared band is 60-70%, and the ultramarine blue coating can reflect most of the energy of the sun in the near-infrared band by optimizing and improving the components, the size and the appearance of the ultramarine blue material, so that the cooling effect is more obvious.

As a general technical concept, the present invention also provides a method for preparing the near-infrared high-reflection blue coating, comprising the steps of:

(1) dissolving the film forming agent, adding the ellipsoidal ultramarine material, and stirring to obtain a uniformly mixed solution;

(2) and (2) blade-coating the uniformly mixed solution obtained in the step (1) to form a film, and then drying and curing (preferably under a vacuum condition) to obtain the near-infrared high-reflection blue coating.

In the preparation method, preferably, the film forming agent is polyvinylidene fluoride, and the mass ratio of the ellipsoidal ultramarine blue material to the film forming agent is controlled to be 1: (0.1-0.5); the dissolving of the film forming agent is to add the film forming agent into 98 percent of N-methyl pyrrolidone solution to be stirred and dissolved, the stirring temperature is controlled to be 20-40 ℃, the stirring time is 3-6h, and the mass ratio of the N-methyl pyrrolidone to the 4A molecular sieve is controlled to be (1.5-3): 1. the ellipsoidal ultramarine material and the film forming agent are controlled in the proportion, so that the film forming efficiency can be ensured, the appearance is neat and available, and the film is uniform and easy to dry after film forming.

In the preparation method, preferably, when the uniformly mixed solution is obtained by stirring, the stirring temperature is controlled to be 20-50 ℃, and the stirring time is 3-10 hours; and controlling the heating temperature to be 50-130 ℃ during drying and curing.

The invention is based on the following principle: 1) materials or colored coatings are widely used on the surfaces of walls and members with color requirements to meet the requirements of people. However, the reflectivity of the commonly used materials is low in the solar spectrum band, and the materials can absorb solar radiation heat (5% of solar radiation energy is distributed in the ultraviolet band (200-. The invention provides an ellipsoidal ultramarine material, which can reflect 75-90% of the energy of the sun in a near infrared band to the maximum, so as to achieve the purposes of cooling and reducing energy consumption. 2) The reflectivity of the material in the near infrared band is mainly influenced by the composition, the size and the shape. In the invention, the synthesized ultramarine blue material is ellipsoidal, the size distribution is narrow, and the reflectivity of the ultramarine blue material to the near infrared band solar spectrum is higher compared with the reflectivity of the commercial ultramarine blue material in the shape and size. The ultramarine material is prepared by taking a 4A molecular sieve as a raw material, the internal structure of the 4A molecular sieve is changed after high-temperature heat treatment, an alpha cage structure with strong water absorption capacity originally existing in the structure disappears, and in addition, the material does not contain functional groups with energy absorption in near-infrared bands such as-CH, -NH and-OH bonds, so that the ultramarine material has no absorption in the near-infrared bands and has high reflectivity. 3) The polyvinylidene fluoride is used as a film forming material, and the polyvinylidene fluoride has a small number of C-H bonds in the interior, so that the polyvinylidene fluoride has weak solar spectrum absorption capacity in a near infrared band, has certain thermal stability and environmental applicability, and can be mixed with a molecular sieve to prepare a cooling coating.

Compared with the prior art, the invention has the advantages that:

1. the ultramarine blue material synthesized by the method has high reflectivity in a near infrared band, can reflect 75-90% of the energy of the sun in the near infrared band, can reduce the absorption of the coating to the solar heat to the maximum extent, and achieves the purpose of reducing energy consumption.

2. The forming method of the near-infrared high-reflection blue coating provided by the invention is simple, convenient and efficient, can form a film through simple blade coating, and can be attached to the surfaces of walls and various components after being dried, so that the aesthetic requirements of people can be met, and the purposes of cooling and reducing energy consumption are achieved.

Drawings

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

Fig. 1 is a visible light image and values of L, a, b of the ellipsoidal ultramarine material of example 1.

FIG. 2 is an SEM photograph of an ellipsoidal ultramarine material in example 1.

FIG. 3 is a graph showing the distribution of the particle size of the ellipsoidal ultramarine material in example 1.

FIG. 4 is a graph of the reflectivity of the ellipsoidal ultramarine material in example 1 in the solar spectral band.

FIG. 5 is an SEM photograph of an ellipsoidal ultramarine material in example 2.

FIG. 6 is a graph of the reflectivity of the ellipsoidal ultramarine material in example 2 in the solar spectral band.

FIG. 7 is an SEM photograph of an ellipsoidal ultramarine material in example 3.

FIG. 8 is a graph of the reflectivity of the ellipsoidal ultramarine material in example 3 in the solar spectral band.

Fig. 9 is a visible light picture of the composite material of comparative example 1.

Fig. 10 is an SEM image of the synthesized material in comparative example 1.

FIG. 11 is a graph showing the reflectance of the composite material of comparative example 1 in the solar spectrum band.

Fig. 12 is a visible light picture of the composite material of comparative example 2.

Fig. 13 is a graph showing the reflectance of the composite material of comparative example 2 in the solar spectral band.

Fig. 14 is a graph comparing the reflectance of the synthetic ultramarine material and the commercial ultramarine material in the solar spectral band in example 1.

FIG. 15 is a diagram of an embodiment of a temperature measuring device.

FIG. 16 is a graph showing the temperature change of the inner wall of an aluminum plate in the case of a coating prepared by synthesizing an ultramarine material and a commercial ultramarine material in example 1 under irradiation of an infrared lamp for 30 minutes.

Fig. 17 is the difference between the two temperature profiles shown in fig. 16.

Detailed Description

In order to facilitate an understanding of the invention, the invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of the invention is not limited to the specific embodiments below.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.

Example 1:

a near-infrared high-reflection blue coating mainly comprises an ellipsoidal ultramarine material and a film forming agent, wherein the mass ratio of the ellipsoidal ultramarine material to polyvinylidene fluoride is 8.5: 1.5.

the raw materials of the ellipsoidal ultramarine material comprise 2.5g of 4A molecular sieve, 3g of sulfur powder, 0.6g of sodium carbonate, 0.5g of quartz powder and 0.3g of rosin.

The synthetic method of the ellipsoidal ultramarine material comprises the following steps: 2.5g of 4A molecular sieve, 3g of sulfur powder, 0.6g of sodium carbonate, 0.5g of quartz powder and 0.3g of rosin were ground and mixed. Pouring the uniformly mixed materials into a quartz crucible with a cover, compacting, and then putting the quartz crucible into a muffle furnace for heat treatment, wherein the heat treatment procedure is as follows: heating to 450 ℃ from room temperature, preserving heat for 30 minutes, then continuing to heat to 980 ℃ and preserving heat for 2 hours, controlling the heating rate to be 5 ℃/min, and then cooling the crucible along with the furnace to obtain a primary product. Then, the obtained product needs to be purified, and the purification process comprises the following steps: the primary product is added into boiling sodium sulfite solution, washing and filtering are carried out, and then deionized water is used for washing a sample until the pH value of a filtrate is less than 9. The obtained material was put into an oven to be dried at 100 ℃ for 6 hours to obtain the ellipsoidal ultramarine blue material in the present example.

The preparation method of the near-infrared high-reflection blue coating comprises the following steps:

(1) adding 1.5g of powdered polyvinylidene fluoride into 20mL of 98% N-methylpyrrolidone solution, carrying out magnetic stirring until a uniformly mixed solution is formed, then adding 8.5g of ellipsoidal ultramarine blue material, and stirring for 5 hours at 25 ℃ to obtain a uniformly mixed solution;

(2) and (3) coating the uniformly mixed solution obtained in the step (1) on an aluminum plate by using a film scraper, placing the aluminum plate in a vacuum drying oven, and performing vacuum drying for 6 hours at 70 ℃ to obtain the near-infrared high-reflection blue coating.

Fig. 1 shows a picture of the synthesized ellipsoidal ultramarine material in the visible light, the color of the material is dark blue, L is 39.4, a is 11.5, and b is-30.5.

The SEM images and the sample size distributions of the ultramarine materials synthesized in this example are shown in fig. 2 and 3, and it can be seen from the images that the morphology of the synthesized material is ellipsoidal, and the sizes are mainly distributed in the interval of 1-3 μm. The method shows that the synthesized material has uniform size under the guidance of the experimental method.

The reflectivity curve of the near-infrared high-reflectivity coating in the embodiment in the solar spectrum band (0.25-2.5 μm) is shown in fig. 4, and it can be known from the figure that the material is blue, so that the reflectivity of the material in the visible light band is low, and the reflectivity of the material in the near-infrared band (780-2500nm) is high, and the reflectivity of the material in the near-infrared band of the solar spectrum reaches 80.7% by calculation, which indicates that the material can be prepared into a coating with high reflectivity in the near-infrared band.

Example 2:

the raw materials of the ellipsoidal ultramarine material comprise 2.5g of 4A molecular sieve, 3g of sulfur powder, 0.3g of sodium carbonate, 0.5g of quartz powder and 0.3g of rosin.

The synthetic method of the ellipsoidal ultramarine material comprises the following steps: 2.5g of 4A molecular sieve, 3g of sulfur powder, 0.3g of sodium carbonate, 0.5g of quartz powder and 0.3g of rosin were ground and mixed. Pouring the uniformly mixed materials into a quartz crucible with a cover, compacting, and then putting the quartz crucible into a muffle furnace for heat treatment, wherein the heat treatment procedure is as follows: heating to 450 ℃ from room temperature, preserving heat for 30 minutes, then continuing to heat to 950 ℃ and preserving heat for 1 hour, controlling the heating rate to be 5 ℃/min, and then cooling the crucible along with the furnace to obtain a primary product. Then, the obtained product needs to be purified, and the purification process comprises the following steps: the primary product is added into boiling sodium sulfite solution, washing and filtering are carried out, and then deionized water is used for washing a sample until the pH value of a filtrate is less than 9. The obtained material was put into an oven to be dried at 100 ℃ for 6 hours to obtain the ellipsoidal ultramarine blue material in the present example.

The SEM image of the ultramarine material synthesized in this example is shown in FIG. 5, and it can be seen that the morphology of the synthesized material is ellipsoidal, and the size is mainly distributed in the interval of 1-3 μm. The method shows that the synthesized material has uniform size under the guidance of the experimental method.

The reflectivity curve of the near-infrared high-reflectivity coating in the embodiment in the solar spectrum band (0.25-2.5 μm) is shown in fig. 6, and it can be known from the figure that the material is blue, so that the reflectivity of the material in the visible light band is low, and the reflectivity of the material in the near-infrared band (780-2500nm) is high, and the reflectivity of the material in the near-infrared band of the solar spectrum reaches 76.9% by calculation, which indicates that the material can be prepared into a coating with high reflectivity in the near-infrared band.

Example 3:

the raw materials of the ellipsoidal ultramarine material comprise 2.5g of 4A molecular sieve, 3g of sulfur powder, 0.5g of sodium carbonate, 0.5g of quartz powder and 0.3g of rosin.

The synthetic method of the ellipsoidal ultramarine material comprises the following steps: 2.5g of 4A molecular sieve, 3g of sulfur powder, 0.5g of sodium carbonate, 0.5g of quartz powder and 0.3g of rosin were ground and mixed. Pouring the uniformly mixed materials into a quartz crucible with a cover, compacting, and then putting the quartz crucible into a muffle furnace for heat treatment, wherein the heat treatment procedure is as follows: heating to 450 ℃ from room temperature, preserving heat for 30 minutes, then continuing to heat to 950 ℃ and preserving heat for 2 hours, controlling the heating rate to be 5 ℃/min, and then cooling the crucible along with the furnace to obtain a primary product. Then, the obtained product needs to be purified, and the purification process comprises the following steps: the primary product is added into boiling sodium sulfite solution, washing and filtering are carried out, and then deionized water is used for washing a sample until the pH value of a filtrate is less than 9. The obtained material was put into an oven to be dried at 100 ℃ for 6 hours to obtain the ellipsoidal ultramarine blue material in the present example.

The SEM photograph of the ultramarine material synthesized in this example is shown in FIG. 7, and it can be seen from the figure that the morphology of the synthesized material is ellipsoidal, and the size is mainly distributed in the interval of 1-3 μm. The method shows that the synthesized material has uniform size under the guidance of the experimental method.

The reflectivity curve of the near-infrared high-reflectivity coating in the embodiment in the solar spectrum band (0.25-2.5 μm) is shown in fig. 8, and it can be known from the figure that the material is blue, so that the reflectivity of the material in the visible light band is low, and the reflectivity of the material in the near-infrared band (780-2500nm) is high, and the reflectivity of the material in the near-infrared band of the solar spectrum reaches 75.3% by calculation, which indicates that the material can be prepared into a coating with near-infrared band high reflectivity.

Comparative example 1:

in this comparative example, the amount of sodium carbonate used in the raw material was changed to 0.2g, and the other conditions were the same as in example 1.

A picture of the ultramarine material synthesized in this comparative example in visible light is shown in fig. 9, the material being green in color.

The SEM image of the ultramarine material synthesized in this example is shown in fig. 10, and it can be seen that the morphology of the synthesized material is a mixture of spherical and square structures.

The reflectance curve of the near-infrared high reflectance coating prepared using the ultramarine blue material of the present comparative example in the near-infrared band (0.25 to 2.5 μm) is shown in fig. 11, and it can be seen from the graph that when the content of sodium carbonate does not satisfy the ratio of sodium ions to sulfur ions, the reflectance of the synthesized material is lower than expected, and the reflectance in the near-infrared band is 73.6%.

Comparative example 2:

in this comparative example, the temperature of the two-stage high-temperature heat treatment was changed to 700 ℃. The other conditions were the same as in example 1.

A picture of the ultramarine material synthesized in this comparative example in visible light is shown in fig. 12, the material color being black and gray.

The reflectance curve of the near-infrared high reflectance coating prepared using the ultramarine blue material of the present comparative example in the near-infrared band (0.25-2.5 μm) is shown in fig. 13, and it can be seen from the graph that when the two-stage high temperature heat treatment temperature is too low, the reflectance in the near-infrared band is 43.5%.

The application example is as follows:

the ellipsoidal ultramarine blue material synthesized in example 1 was compared with commercially purchased ultramarine blue material, the reflectivity of the ultramarine blue material in the solar spectral band is shown in fig. 14, the coating was prepared by the method provided in example 1, an aluminum plate covered with the ultramarine blue material was placed on the upper part of a box having a heat-insulating effect, and the temperature of the back surface of the aluminum plate was measured by a temperature sensor to test the cooling effect of the two different materials. The test apparatus is shown in fig. 15.

The two groups of samples are placed under an infrared lamp for 30 minutes, the test cooling effect is shown in fig. 16, and it can be seen from the graph that in the 30 minutes, in the first 10 minutes, the temperature of the two materials rises relatively fast, in the last 10 minutes, the temperature tends to be stable, and the surfaces of the two materials have obvious temperature difference. The temperature difference is shown in fig. 17, and it can be seen that the maximum temperature difference reaches 2 ℃, and the average temperature difference is about 1 ℃.

The result shows that the coating prepared by using the ellipsoidal ultramarine blue material obtained in the embodiment 1 has high reflectivity in the near infrared band of the solar spectrum, can achieve the purposes of cooling and saving energy, and has better effect than commercial ultramarine blue materials.

Claims

1. The ultramarine material for preparing the near-infrared high-reflection blue coating is characterized by comprising the following raw materials in parts by weight:

2. the ultramarine material according to claim 1, wherein the mass ratio of the sulfur powder to the anhydrous sodium carbonate is 1: (0.1-0.2), wherein the mass ratio of the 4A molecular sieve to the quartz powder is (4-8): 1.

3. ultramarine material according to claim 1 or 2, characterized in that the ultramarine material is ellipsoidal with a size distribution of between 1 and 3 microns.

4. A method for preparing an ultramarine material according to any one of claims 1 to 3, comprising the steps of:

(2) and (2) carrying out first-stage low-temperature heat treatment and second-stage high-temperature heat treatment on the mixture obtained in the step (1), and then purifying to obtain the ultramarine blue material.

5. The method as claimed in claim 4, wherein the temperature of the first-stage low-temperature heat treatment is 400-500 ℃, the temperature rising speed is 5-8 ℃/min, and the time is 20-60 min; the temperature of the two-stage high-temperature heat treatment is 950-.

6. The preparation method according to claim 4 or 5, wherein the purification is carried out by using a sodium sulfite boiling solution, and the mass ratio of sodium sulfite to deionized water in the sodium sulfite boiling solution is 1: (30-50).

7. The near-infrared high-reflection blue coating is characterized by mainly comprising an ellipsoidal ultramarine material and a film forming agent, and the reflectivity of the blue coating in a near-infrared band is 75-90%.

8. The blue coating according to claim 7, wherein said ellipsoidal ultramarine material is an ultramarine material produced according to any one of claims 1 to 3 or according to the production method of any one of claims 4 to 6.

9. A method for preparing a near-infrared highly reflective blue coating according to claim 7 or 8, comprising the steps of:

(2) and (2) blade-coating the uniformly mixed solution obtained in the step (1) to form a film, and then drying and curing to obtain the near-infrared high-reflection blue coating.

10. The preparation method of claim 9, wherein the film forming agent is polyvinylidene fluoride, and the mass ratio of the ellipsoidal ultramarine material to the film forming agent is controlled to be 1: (0.1-0.5);

the dissolving of the film forming agent is to add the film forming agent into 98 percent of N-methyl pyrrolidone solution to be stirred and dissolved, the stirring temperature is controlled to be 20-40 ℃, the stirring time is 3-6h, and the mass ratio of the N-methyl pyrrolidone to the 4A molecular sieve is controlled to be (1.5-3): 1;

when the uniformly mixed solution is obtained by stirring, the stirring temperature is controlled to be 20-50 ℃, and the stirring time is 3-10 h; and controlling the heating temperature to be 50-130 ℃ during drying and curing.