WO2020076138A1 - Complex coating solution, metal substrate structure manufactured using same, and manufacturing method therefor - Google Patents

Abstract

A method for manufacturing a complex coating solution may comprise the steps of: preparing a base solution containing a metal salt; preparing a graphite intercalation compound by providing graphite to the base solution to intercalate an anion of the metal salt between layers of the graphite; forming an expandable graphite by thermally treating the graphite intercalation compound; preparing a graphite nanoplate by dispersing the expandable graphite; and preparing a complex coating solution by mixing the graphite nanoplate and a polymer.

Description

Composite coating solution, metal substrate structure manufactured using the same, and method for manufacturing same

The present application relates to a composite coating solution, a metal substrate structure manufactured using the same, and a method for manufacturing the same, more specifically, a composite coating solution comprising a graphite nanoplate and a silicon-based inorganic polymer, a metal substrate structure produced using the same, And a method of manufacturing the same.

Metals have high electrical conductivity and mechanical properties, and are used in various industrial fields. However, the metal can also be oxidized by moisture in the atmosphere, and thus improving the corrosion resistance and oxidation resistance of the metal is an important issue.

Accordingly, materials being studied for improving corrosion resistance and oxidation resistance include non-oxidizing metals or metal compounds, and non-metal compounds, and electrochemical deposition, physical vapor deposition, chemical vapor deposition on the metal surface to be protected. It is manufactured by a method such as dip coating.

However, ceramic materials such as metal oxides require high vacuum and high temperature processes, and thus require high process costs. In addition, in the case of an organic polymer, the process cost may be reduced, but at a high temperature, the inherent properties of the material may be lost and carbonized, and cracks may occur in the coating layer.

Accordingly, a coating liquid material in which a ceramic material such as an organic polymer and a metal oxide is mixed has been studied. For example, the Republic of Korea Patent Publication No. 10-1081988 (Application No. 10-2008-0132540) is selected from the group consisting of polyester resin, epoxy resin, polyurethane resin, acrylic resin, fluororesin, polycarbonate resin and phenol resin. 100 parts by weight of one or more main resins, 1 to 20 parts by weight of a melamine-based curing agent, 1 to 20 parts by weight of one or more of carbon black and carbon nanotubes, 1 to 40 parts by weight of metal powder, and 0.001 to 20 parts of organic clay Disclosed is a coating composition comprising parts by weight and having excellent conductivity and corrosion resistance.

One technical problem to be solved by the present application is to prepare a coating layer containing a metal oxide and a graphite nanoplate by curing a composite coating solution containing a polymer and a graphite nanoplate, and a composite coating solution having improved oxidation resistance and corrosion resistance, and using the same It is to provide a metal substrate structure, and a method for manufacturing the same.

Another technical problem to be solved by the present application is to provide a composite coating solution having electrical conductivity, including a graphite nanoplate, a metal substrate structure manufactured using the same, and a method of manufacturing the same.

The technical problem to be solved by the present application is not limited to the above.

In order to solve the above technical problem, the present application provides a method for producing a composite coating solution.

According to one embodiment, the method for preparing the composite coating solution comprises: preparing a base solution containing a metal salt, providing graphite to the base solution, providing graphite to the base solution, and anion of the metal salt to the graphite Inserting into the interlayer of, preparing a graphite interlayer compound, heat-treating the graphite interlayer compound to form expanded graphite, dispersing the expanded graphite to prepare a graphite nanoplate, and the graphite nanoplate, and By mixing the polymer, it may include the step of preparing a composite coating solution.

According to one embodiment, the step of heat-treating the graphite interlayer compound, the thermal decomposition of the anion of the metal salt contained in the graphite interlayer compound, and the expansion force of the gas formed by the thermal decomposition of the anion, the graphite interlayer compound It may include the step of manufacturing the expanded graphite is increased interlayer distance.

According to an embodiment, as the process temperature or the process pressure of the step of heat-treating the graphite interlayer compound increases, the amount of defects provided in the graphite nanoplate may be increased.

According to one embodiment, according to the polarity of the polymer, including adjusting the amount of defects provided in the graphite nanoplate, as the polarity of the polymer increases, the amount of defects provided in the graphite nanoplate increases It can include.

According to one embodiment, the polymer is polysilazane, and the solvent of the composite coating solution may include a non-polar solvent.

According to an embodiment, the polymer is polysiloxane, and the solvent of the composite coating solution may include a polar solvent.

According to one embodiment, the metal salt may include at least one of azide salt, carbonate, nitrate, sulfate, or phosphate.

In order to solve the above technical problem, the present application provides a composite coating solution.

According to an embodiment, the composite coating solution includes a graphite nanoplate and a polymer, and with respect to 100 parts by weight of the total of the graphite nanoplate and the polymer, the graphite nanoplate is 10 parts by weight or more and 50 parts by weight or less , And the polymer may include 50 parts by weight or more and 90 parts by weight or less.

According to an embodiment, the polymer may include either an organic polymer or an inorganic polymer.

According to an embodiment, the organic polymer may include at least one of an epoxy polymer, a cellulose polymer, a vinyl polymer, an acrylic polymer, a fluorine polymer, an amide polymer, an imide polymer, or an acetate polymer. .

According to one embodiment, the inorganic polymer may include at least one of polysiloxane, polysilazane, or polysilicate.

In order to solve the above technical problem, the present application provides a coating method using a composite coating solution.

According to one embodiment, in the coating method using the composite coating solution, when the polymer of the composite coating solution is polysilazane, the composite coating solution is coated on a metal substrate by either a spray coating method or a spin coating method. It may include.

According to an embodiment, the coating method using the composite coating solution, when the polymer of the composite coating solution is polysiloxane, coats the composite coating solution on a metal substrate by either a bar coating method or a doctor blade coating method It may include.

According to one embodiment, the step of preparing a coating layer by hot pressing the pre-coating layer prepared by the coating method using the composite coating solution, the amount of the graphite nanoplate in the pre-coating layer increases, reducing the process pressure It may include.

In order to solve the above technical problem, the present application provides a metal substrate structure.

According to one embodiment, the metal substrate structure, a metal substrate, and disposed on the metal substrate, comprises a graphite nanoplate, and a coating layer comprising silicon oxide, the coating layer, the silicon-carbon bond in the IR analysis method It does not include, it may include a higher oxidation resistance and stone resistance than the metal substrate.

According to an embodiment, the metal substrate structure may include that as the amount of the silicon oxide in the coating layer increases, corrosion resistance increases.

Method of manufacturing a composite coating solution according to an embodiment of the present invention, preparing a base solution containing a metal salt, providing graphite to the base solution, inserting anions of the metal salt into the interlayer of the graphite, graphite interlayer compound The step of preparing, forming the expanded graphite by heat-treating the graphite interlayer compound, dispersing the expanded graphite, preparing a graphite nanoplate, and mixing the graphite nanoplate and the polymer to prepare a composite coating solution It may include the steps.

In the step of heat-treating the graphite interlayer compound, the anion inserted between the graphite interlayers may be thermally decomposed. Accordingly, a gas may be formed, and the expanded graphite may be generated by the expanding force of the gas. At this time, the expansion force of the gas is directly received, the carbon-carbon bond is broken, and the expanded graphite having defects can be produced. Therefore, the more the anions inserted, the more defects can be increased in the expanded graphite. In particular, when the anion contains oxygen, the oxidizing gas may be formed, and accordingly, an oxygen-based functional group may be formed on the expanded graphite. In addition, as the process time and process temperature of the heat treatment step increase, the defects may increase. That is, according to the above, the amount of the defect in the expanded graphite can be adjusted.

The step of preparing the composite coating solution may include mixing the graphite nanoplate with 10 to 50 parts by weight, and the polymer with the remaining parts by weight, compared to 100 parts by weight of the total of the graphite nanoplate and the polymer. Accordingly, a composite coating solution in which the graphite nanoplate and the polymer are uniformly dispersed without aggregation, and the adhesion between the metal substrate and the metal is improved may be prepared.

The composite coating solution prepared according to the above may be coated on the metal substrate and then cured to form a coating layer. The composite coating solution may include a silicon-based inorganic polymer, and the coating layer prepared accordingly may include the graphite nanoplate and silicon oxide prepared by curing the silicon-based inorganic polymer.

The silicon oxide may exhibit corrosion resistance and oxidation resistance, and the graphite nanoplate may exhibit electrical conductivity. Accordingly, the metal substrate on which the coating layer is formed can be improved in corrosion resistance and oxidation resistance, and also has electrical conductivity, so that it can be easily used in an industrial field where electrical conductivity of the metal is required.

1 is a flow chart for explaining a method of manufacturing a composite coating solution according to an embodiment of the present invention.

2 to 4 are views for explaining a method of manufacturing a composite coating solution according to an embodiment of the present invention.

5 to 6 are views for explaining a method of manufacturing a metal substrate structure according to an embodiment of the present invention.

7 to 10 are views showing a scanning electron microscope (SEM) image of a graphite interlayer compound and expanded graphite in a method of manufacturing a composite coating solution according to an embodiment of the present invention.

11 to 12 are views showing an atomic force microscope (AFM) image, particle size distribution, and particle thickness distribution of a graphite nanoplate in a method of manufacturing a composite coating solution according to an embodiment of the present invention.

13 is a view illustrating a transmission electron microscope (TEM), a high resolution transmission electron microscope (HRTEM), and a fast Fourier transform (FFT) image of a graphite nanoplate in a method of manufacturing a composite coating solution according to an embodiment of the present invention.

14 is a view showing an image photographed while irradiating light to a composite coating solution according to an embodiment of the present invention.

15 is a view showing a scanning electron microscope (SEM) image of a coating layer of a metal substrate structure according to an embodiment of the present invention.

16 to 17 are views showing an infrared (IR) spectrum of a coating layer of a metal substrate structure according to an embodiment of the present invention.

18 to 19 are views showing resistance before and after heat treatment of the metal substrate structure according to the embodiment of the present invention.

20 to 21 are views showing a scanning electron microscope (SEM) image before and after heat treatment of a metal substrate structure according to an embodiment of the present invention.

22 is a view showing an X-ray diffraction pattern (XRD) before and after heat treatment of a metal substrate structure according to an embodiment of the present invention.

23 to 24 are diagrams showing sample images before and after brine treatment of a metal substrate structure according to Comparative Example 3 and Experimental Example 2-1 of the present invention, and scanning electron microscope (SEM) images.

25 to 26 are views showing a sample image and a scanning electron microscope (SEM) image after saline treatment of the metal substrate structure according to Comparative Example 4 and Experimental Example 2-1 of the present invention.

27 to 28 are views showing a sample image after sulfuric acid treatment and a scanning electron microscope (SEM) image of the metal substrate structure according to Comparative Example 4 and Experimental Example 2-1 of the present invention.

29 to 30 are diagrams showing a polarization curve and an impedance of a metal substrate structure according to an embodiment of the present invention.

31 is a view showing the electrical conductivity and adhesion test results according to the graphite nanoplate mass ratio of the metal substrate structure according to Experimental Example 2-2 of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the technical spirit of the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed contents are thorough and complete and that the spirit of the present invention is sufficiently conveyed to those skilled in the art.

In the present specification, when a component is referred to as being on another component, it means that it may be formed directly on another component, or a third component may be interposed between them. In addition, in the drawings, the thickness of the films and regions are exaggerated for effective description of the technical content.

Further, in various embodiments of the present specification, terms such as first, second, and third are used to describe various components, but these components should not be limited by these terms. These terms are only used to distinguish one component from another component. Therefore, what is referred to as the first component in one embodiment may be referred to as the second component in another embodiment. Each embodiment described and illustrated herein also includes its complementary embodiment. Also, in this specification, 'and / or' is used to mean including at least one of the components listed before and after.

In the specification, a singular expression includes a plural expression unless the context clearly indicates otherwise. Also, terms such as “include” or “have” are intended to indicate the presence of features, numbers, steps, elements or combinations thereof described in the specification, and one or more other features, numbers, steps, or configurations. It should not be understood as excluding the possibility of the presence or addition of elements or combinations thereof.

In addition, in the following description of the present invention, when it is determined that detailed descriptions of related well-known functions or configurations may unnecessarily obscure the subject matter of the present invention, detailed descriptions thereof will be omitted.

1 is a flow chart for explaining a method of manufacturing a composite coating solution according to an embodiment of the present invention, FIGS. 2 to 4 are views for explaining a method of manufacturing a composite coating solution according to an embodiment of the present invention.

Referring to Figure 1, a base solution containing a metal salt may be prepared (S110).

For example, the metal salt may include at least one of azide salt, carbonate, nitrate, sulfate, or phosphate, and specifically, the metal salt may be sodium azide (NaN ₂ ).

1 and 2, by providing graphite 100 in the base solution, the anion 210 of the metal salt is inserted between the layers of the graphite 100, the graphite interlayer compound 200 can be prepared Yes (S120).

According to one embodiment, the graphite 100 may be provided in the base solution. The graphite interlayer compound 200 in which the anion 210 of the metal salt is inserted between the layers of the graphite 100 is prepared by stirring the base solution provided with the graphite 100, as shown in FIG. 2. Can be.

Specifically, for example, when the metal salt is the sodium azide, the base solution may be prepared by mixing the sodium azide and distilled water. After mixing the graphite (100) in the base solution, stirred and layers the azide Chemistry azide anion of sodium (N ₃ ^-) in the graphite 100 is the above-graphite intercalation compound (200) inserted into a prepared Can be.

1 to 3, expanded graphite 300 may be formed by heat-treating the graphite interlayer compound 200 (S130).

According to an embodiment, the expanded graphite 300 may be prepared by thermally decomposing the anion 210 in the graphite interlayer compound 200. That is, the anion 210 provided between the layers of the graphite 100 is thermally decomposed, and gas may be formed. Accordingly, as illustrated in FIG. 3, the interlayer distance of the graphite 100 is increased. The expanded graphite 300 may be manufactured, and the expanded graphite 300 may include residues or impurities 310 by thermal decomposition of the anion 210 between layers.

That is, the expanded graphite 300 manufactured according to the above-described method may have a larger interlayer distance than the graphite interlayer compound 200. That is, as shown in FIG. 3, the expanded graphite 300 may have an interlayer distance indicated by l ₂ , and as shown in FIG. 2, the graphite interlayer compound 200 is indicated by l ₁ When having an interlayer distance, the interlayer distance l ₂ of the expanded graphite 300 may have a larger value than the interlayer distance l ₁ of the graphite interlayer compound 200.

According to an embodiment, as described above, the anion 210 is thermally decomposed and the gas generated may rapidly expand in volume. At this time, when the expansion force of the gas is directly applied between the layers of the graphite, the carbon-carbon bond may be broken, and accordingly, the expanded graphite 300 provided with voids or defects may be manufactured.

At this time, as the process temperature or process time of the heat treatment process increases, the amount of gas generated increases, and accordingly, the amount of defects provided to the expanded graphite 300 may increase.

According to another embodiment, the expanded graphite 300 may be manufactured by at least one method among acid treatment, plasma treatment, or microwave in addition to the heat treatment process.

Specifically, for example, when the expanded graphite 300 is manufactured by plasma treatment of the graphite interlayer compound 200, as described above, as the plasma pressure increases, defects provided to the expanded graphite 300 The amount of can be increased.

In addition, depending on the type of the metal salt 200 and the mixing ratio of the metal salt 200 and the graphite 100, the amount of defects provided to the expanded graphite 300 may be controlled.

According to an embodiment, the mixing ratio of the metal salt and the graphite is the same, but different metal salts may be mixed. In this case, depending on the presence or absence of oxygen in the anion 210 of the metal salt, the amount of defects provided to the expanded graphite 300 may be determined.

For example, when the anion 210 contains the oxygen, an oxidizing gas may be generated by thermal decomposition of the anion 210. Accordingly, the expanded graphite 300 in which the amount of defects is increased by oxidation is formed by the oxidizing gas. At this time, the metal salt may be at least one of sulfate, nitrate, or carbonate.

For another example, the anion 210 may not include the oxygen. In this case, unlike the case where the anion 210 contains oxygen, the gas may provide only an expansion force. Accordingly, the amount of defects provided in the expanded graphite 300 may be relatively small compared to the case where the anion 210 contains oxygen. In this case, the metal salt may be an azide salt.

According to one embodiment, the type of the metal salt is the same, but the mixing ratio of the metal salt and the graphite 100 may be changed. In this case, as the mixing ratio of the metal salt to the graphite 100 increases, the amount of gas generated may increase, and accordingly, the amount of defects provided to the expanded graphite 300 may increase.

1 and 4, the expanded graphite 300 is dispersed to prepare a graphite nanoplate 400 (S140).

According to an embodiment, as shown in FIG. 4, the graphite nanoplate 400 may be manufactured by providing and expanding the expanded graphite 300 in a solvent.

For example, the solvent may be at least one of a fatty solvent, an aromatic solvent, a polar solvent, or a non-polar solvent. In addition, for example, the expanded graphite 300 may be dispersed by at least one of a stirrer, an ultrasonic disperser, a vibration mixer, a share mixer, a ball mill, an attraction mill, or a planetary mill.

Specifically, for example, after providing the expanded graphite 300 to xylene, which is a non-polar solvent, the graphite nanoplate 400 may be manufactured by dispersing it using an ultrasonic disperser.

Referring to FIG. 1, a composite coating solution may be prepared by mixing the graphite nanoplate 400 and a polymer (S150).

According to one embodiment, the polymer may be an organic polymer or an inorganic polymer.

For example, the organic polymer may be at least one of an epoxy polymer, a cellulose polymer, a vinyl polymer, an acrylic polymer, a fluorine polymer, an amide polymer, an imide polymer, or an acetate polymer.

For another example, the inorganic polymer may be at least one of polysiloxane, polysilazane, or polysilicate.

According to an embodiment, the graphite nanoplate 400 may include defects, and the polymer may be selected according to the amount of defects in the graphite nanoplate 400.

As described above, the expanded graphite 300 may include the defect. Accordingly, by dispersing the expanded graphite 300, defects may be distributed in the manufactured graphite nanoplate 400. For example, as described above, the expanded graphite 300 may be oxidized by the oxidizing gas, and accordingly, the graphite nanoplate may further include an oxygen-based functional group. Specifically, for example, the oxygen-based functional group may be at least one of a hydroxy group (hydroxyl) or a carboxyl group (carboxyl).

Accordingly, as the amount of defects in the graphite nanoplate 400 increases, it may be mixed with the polymer 1120 that exhibits relatively polarity.

Specifically, for example, when the defects in the graphite nanoplate 400 are relatively small, the polymer 1120 may be polysilazane represented by <Formula 1> below, and also, the The composite coating solution can be prepared using a non-polar solvent. For example, the non-polar solvent may be at least one selected from xylene, dibutyl ether, and the like.

<Formula 1>

For another example, when the defects in the graphite nanoplate 400 are relatively large, the polymer 1120 may be polysiloxane represented by <Formula 2> below, and the composite coating solution may also be It can be prepared using a polar solvent. For example, the polar solvent may be at least one selected from isopropyl alcohol and the like.

<Formula 2>

According to one embodiment, the composite coating solution may include 10 to 50 parts by weight of the graphite nanoplate 400, compared to 100 parts by weight of the total of the graphite nanoplate 400 and the polymer 1120, and the polymer (1120) may be included as the remaining weight parts.

If, unlike the above, the composite coating solution contains less than 10 parts by weight of the graphite nanoplate 400, the electrical conductivity of the coating layer manufactured using the composite coating solution may be reduced. In addition, when the composite coating solution contains more than 50 parts by weight of the graphite nanoplate 400, adhesive strength of the composite coating solution may be reduced, and accordingly, it is easy to manufacture the coating layer using the composite coating solution. You may not.

However, according to one embodiment, as described above, the composite coating solution may include 10 to 50 parts by weight of the graphite nanoplate 400, and accordingly, the coating layer on the metal substrate using the composite coating solution This can be easily manufactured.

5 to 6 are views for explaining a method of manufacturing a metal substrate structure according to an embodiment of the present invention.

5 to 6, the coating layer 1200 is a step of preparing a pre-coating layer 1100 by coating a composite coating solution on the metal substrate 1000, and curing the pre-coating layer 1100 Can be manufactured.

Referring to FIG. 5, a method of coating the composite coating solution on the metal substrate 1000 may be selected according to the viscosity of the composite coating solution.

Specifically, for example, when the composite coating solution includes polysilazane, the viscosity of the composite coating solution may be relatively low. In this case, the composite coating solution does not maintain the shape of droplets on the metal substrate 1000, and spreading may occur. Accordingly, the composite coating solution is any one selected from spray coating, spin coating, etc. It can be coated with.

For another example, when the composite coating solution includes polysiloxane, the viscosity of the composite coating solution may be relatively high. In this case, the spray nozzle is clogged in the process of spraying the composite coating solution on the metal substrate 1000. Or, it may be aggregated on the metal substrate 1000. Accordingly, the composite coating solution may be coated by any one method selected from a bar coating method, a doctor blade coating method, and the like.

Referring to FIG. 6, a method of curing the pre-coating layer 1100 may be selected according to the viscosity of the composite coating solution, as described above.

For example, as described above, when the composite coating solution includes the polysilazane, a spreading phenomenon of droplets may occur, and accordingly, photocuring in which pressure is not directly applied to the pre-coating layer 1100. Alternatively, the coating layer 1200 may be manufactured by any one process among heat treatments. Specifically, for example, the coating layer 1200 may be manufactured by photocuring the preliminary coating layer 1100. Alternatively, for example, the coating layer 1200 may be manufactured by heat-treating the pre-coating layer 1100 in a water vapor or ammonia gas atmosphere.

For another example, when the pre-coating layer 1100 includes polysiloxane, unlike the case where the polysiloxane is included, a droplet shape may be maintained, and accordingly, the coating layer 1200 may include the pre-coating layer 1100. ) Can be prepared by hot pressing. Therefore, the coating layer 1200 may be formed in a shorter time than the photocuring method. Specifically, for example, the coating layer 1200 may be manufactured by applying a pressure of 5 ton to the pre-coating layer 1100 and performing it at a temperature of 200 ° C. for 10 minutes.

At this time, as described above, as the amount of the graphite nanoplate 1110 in the composite coating solution increases, adhesion to the metal substrate 1000 may decrease. Accordingly, as the amount of the graphite nanoplate 1110 in the pre-coating layer 1100 increases, the process pressure of the hot press process decreases, thereby reducing the loss of the pre-coating layer 1100 on the metal substrate 1000. Can be prevented.

According to an embodiment, the coating layer 1200 manufactured as described above may include an inorganic material formed by curing the polymer 1120 in the pre-coating layer 1100, and the graphite nanoplate 1110.

Specifically, for example, when the pre-coating layer 1100 includes polysiloxane, the inorganic material 1220 may be silicon oxide. In addition, the inorganic material 1220 may not include the silicon-carbon bond indicated in <Formula 2>, and accordingly, the coating layer 1200 with improved heat resistance may be manufactured.

In this case, as the amount of the silicon oxide is increased, the corrosion resistance may be improved, and as the amount of the graphite nanoplate 1110 is increased, the electrical conductivity of the coating layer 1200 may be improved.

Therefore, the metal substrate structure may have improved oxidation resistance and corrosion resistance than the metal substrate 1000. In addition, the metal substrate structure may have electrical conductivity, and thus, corrosion of the metal substrate 1000 may be prevented, and at the same time, electrical conductivity characteristics of the metal substrate 1000 may be maintained. Accordingly, a coating method using a composite coating solution according to an embodiment of the present invention may be easily used in various industrial fields having oxidation resistance and corrosion resistance, but requiring electrical conductivity of the metal substrate 1000.

Hereinafter, a method for manufacturing a composite coating solution according to a specific experimental example of the present invention, and a coating layer using the same, and a characteristic evaluation result are described.

Preparation of composite coating solution according to Experimental Example 1-1

200 g of sulfate was added to 1.5 kg of distilled water, followed by stirring for 1 hour to prepare a base solution.

After adding 100 g of graphite to the base solution, after stirring for 3 hours, the residue was washed with 3 kg of distilled water to prepare a graphite interlayer compound.

After filtering the graphite interlayer compound, it was dried at a temperature of 60 ° C. for 24 hours to obtain a graphite interlayer compound powder.

After providing 2.5 g of the graphite interlayer compound powder to an alumina container, the alumina container was charged to a heat treatment equipment.

The heat treatment equipment was maintained at a temperature of 500 ° C. for 20 minutes to prepare expanded graphite from the graphite interlayer compound powder.

A dispersion solution was prepared by providing the expanded graphite to xylene.

The dispersion solution was dispersed with an ultrasonic disperser for 1 hour to prepare a graphite nanoplate.

After adding a polysilazane or polysiloxane solution to the dispersion solution containing the graphite nanoplate, and dispersing for 1 hour using an ultrasonic disperser, a composite coating solution according to Experimental Example 1-1 was prepared.

Preparation of composite coating solution according to Experimental Example 1-2

Prepared in the same manner as the method for preparing the composite coating solution according to Experimental Example 1-1 described above, 200 g of azide salt was added instead of 200 g of the sulfate to prepare a composite coating solution according to Experimental Example 1-2.

Preparation of composite coating solution according to Experimental Example 1-3

Prepared in the same manner as the method for preparing the composite coating solution according to Experimental Example 1-1 described above, 500 g of azide salt was added instead of 200 g of the sulfate to prepare a composite coating solution according to Experimental Example 1-3.

The mixing ratio of the metal salt to the graphite of the composite coating solution according to Experimental Examples 1-1 to 1-3 was prepared in Table 1 below.

	Type of metal salt	Metal salt: graphite (w / w)
Experimental Example 1-1	sulfate	2: 1
Experimental Example 1-2	Azide salt	2: 1
Experimental Example 1-3	Azide salt	5: 1

7 to 10 are views showing a scanning electron microscope (SEM) image of a graphite interlayer compound and expanded graphite in a method of manufacturing a composite coating solution according to an embodiment of the present invention.

Referring to FIG. 7, a surface image of a graphite interlayer compound prepared in a method of preparing a composite coating solution according to Experimental Examples 1-1 to 1-3 of the present invention was photographed.

In addition, referring to FIGS. 8 to 10, surface images of the expanded graphite produced in the method of preparing the coating solution according to Experimental Examples 1-1 to Experimental Example 1-3 of the present invention were photographed.

Accordingly, as described above with reference to FIGS. 1 to 3, it can be seen that, compared to the graphite interlayer compound, the interlayer spacing of the expanded graphite is further increased.

8 to 10, it can be seen that the expanded graphite has a structure that changes depending on the type of the metal salt inserted between the layers of the graphite.

Referring to <Table 1>, as shown above with reference to Figures 1 to 3, compared to the expanded graphite prepared in the composite coating solution according to Experimental Example 1-2 shown in Figure 9, the experiment shown in Figure 10 It can be seen that the expanded graphite prepared in the composite coating solution according to Examples 1-3 has a wider interlayer spacing.

 In addition, the expanded graphite prepared in the composite coating solution according to Experimental Example 1-1 shown in FIG. 8 and the expanded graphite prepared in the composite coating solution according to FIGS. 1-2 are made of different metal salts, and accordingly, different It was confirmed to have a structure.

G peak, D peak, and 2D using Raman spectroscopy to confirm the oxidation degree and particle thickness of the expanded graphite prepared in the above-described Experimental Example 1-1 to the manufacturing method of the composite coating solution according to Experimental Example 1-3 The value of the peak was measured. Here, the G peak is a peak observed in the graphite-based material, the D peak is a peak indicating a defect in the structure, and the 2D peak is a peak related to thickness. Accordingly, for the measured G peak, D peak, and 2D peak, the values of the D peak compared to the G peak and the 2D peak compared to the G peak were prepared in <Table 2> below.

	D peak / G peak	2D peak / G peak
Experimental Example 1-1	0.033	0.35
Experimental Example 1-2	0.081	0.37
Experimental Example 1-3	0.181	0.38

Referring to <Table 2>, as described above with reference to FIGS. 1 to 3, the higher the mixing ratio of the metal salt to the graphite, the greater the defects of the expanded graphite prepared, and accordingly, the experiment It can be seen that the expanded graphite prepared in the composite coating solution according to Examples 1-3 has the largest D peak / G peak value.

In addition, as described above with reference to FIGS. 8 to 10, it can be seen that the expanded graphite prepared in the composite coating solution according to Experimental Examples 1-3 has the largest interlayer spacing. However, the thickness of the expanded graphite prepared as described above may be thin, and accordingly, the value of the 2D peak / G peak of the expanded graphite prepared in the composite coating solution according to Experimental Examples 1-1 to Experimental Examples 1-3. It can be seen that these are substantially similar to each other.

11 to 12 are views showing an atomic force microscope (AFM) image, particle size distribution, and particle thickness distribution of a graphite nanoplate in a method of manufacturing a composite coating solution according to an embodiment of the present invention.

Referring to FIG. 11, the size and thickness of the graphite nanoplates prepared according to Experimental Examples 1-1 to 1-3 of the present invention were confirmed.

As shown in Figure 11, it was confirmed that the graphite nanoplate has a size of 2um x 2um and a thickness of 6nm.

Referring to FIG. 12, as shown in FIG. 11, about 100 of the graphite nanoplates prepared with reference to FIGS. 1 to 4, an atomic force microscope image was measured, and the particle size of the 100 graphite nanoplates was measured. The distribution of and the distribution of particle thickness are summarized and shown.

12, it was confirmed that the graphite nanoplate has an average size of 2 to 3 um and a thickness of 10 to 20 nm.

13 is a view showing a transmission electron microscope (TEM), a high resolution transmission electron microscope (HRTEM), and a fast Fourier transform (FFT) image of a graphite nanoplate in a method of manufacturing a composite coating solution according to an embodiment of the present invention.

13, the thickness and structure of the graphite nanoplates prepared according to Experimental Examples 1-1 to 1-3 of the present invention were confirmed.

As shown in FIG. 13B, it can be seen that the graphite nanoplate has a stacked structure of about 15 graphite monolayers of about 0.34 nm.

In addition, referring to (c) of FIG. 13, it can be seen that the graphite nanoplate has a (100) plane and a (006) plane.

14 is a view showing an image photographed while irradiating light to a composite coating solution according to an embodiment of the present invention.

14, a composite coating solution according to Experimental Examples 1-1 to Experimental Example 1-3 of the present invention, and a comparative example of the composite coating solution were taken as a dispersion containing the graphite nanoplate alone.

14 (a) and (c), the composite coating solution is the graphite nanoplate and the polymer are relatively uniformly dispersed, and accordingly, when irradiating light to the composite coating solution, the light It was confirmed that the course was not visible.

14 (b), and (d), unlike the above-mentioned with reference to FIGS. 14 (a) and 14 (c), the dispersion containing the graphite nanoplate alone without the polymer is relatively As a result, dispersibility may decrease, and accordingly, a tindle phenomenon in which the path of light irradiated to the dispersion is confirmed is observed.

Preparation of metal substrate structure according to Experimental Example 2-1

The composite coating solution according to Experimental Example 1-3 was used, but the composite coating solution was prepared to include the polysilazane in the polysilazane or the polysiloxane.

After spray coating the composite coating solution on the surface of a copper substrate or an aluminum substrate, heat treatment was performed for 24 hours at a temperature of 180 ° C. in a water vapor or ammonia gas atmosphere to prepare a metal substrate structure according to Experimental Example 2-1.

Preparation of metal substrate structure according to Experimental Example 2-2

The composite coating solution according to Experimental Example 1-3 was used, but the composite coating solution was prepared to include the polysiloxane in the polysilazane or the polysiloxane.

The composite coating solution was coated on the surface of a copper substrate or an aluminum substrate at a rate of 1 cm / s, and then dried at a temperature of 160 ° C. for 5 minutes to prepare a pre-coating layer.

A metal substrate structure according to Experimental Example 2-2 was prepared by hot pressing the pre-coated layer at a pressure of 5 tons and a temperature of 200 ° C. for 10 minutes.

The manufacturing process of the metal substrate structure according to the above-described Experimental Examples 2-1 to 2-2 was prepared in <Table 3> below.

	Polymer type in the composite coating solution	Curing process
Experimental Example 2-1	Polysilazane	Heat treatment or photocuring
Experimental Example 2-2	Polysiloxane	Hot press or heat treatment

15 is a view showing a scanning electron microscope (SEM) image of a coating layer of a metal substrate structure according to an embodiment of the present invention.

15, a comparative example of the coating layer prepared according to Experimental Example 2-1 and Experimental Example 2-2 of the present invention, Comparative Example 2-1 using the same polymer as the polymer used in the manufacturing process of the coating layer And a metal substrate structure according to Comparative Example 2-2. Accordingly, the coating layer prepared according to Experimental Example 2-1 and Experimental Example 2-2 (FIG. 15 (b)) and the coating layer prepared according to Comparative Example 2-1 and Comparative Example 2-2 (FIG. 15) (a)) was photographed.

That is, referring to (a) of Figure 15, after coating the polysilazane or polysiloxane, the surface of the coating layer prepared by curing, that is, prepared according to Comparative Example 2-1 or 2-2 of the present invention Was confirmed.

It was confirmed that the polymer coating layer shown in FIG. 15 (a) had cracks compared to the coating layer shown in FIG. 15 (b).

16 to 17 are views showing an infrared (IR) spectrum of a coating layer of a metal substrate structure according to an embodiment of the present invention.

Referring to FIG. 16, as described above with reference to FIG. 15, it was confirmed that the coating layer prepared according to Comparative Example 2-1 prepared using the polysilazane had a silicon-oxygen-silicon peak.

On the other hand, it was confirmed that the coating layer prepared according to Comparative Example 2-2 prepared using the polysiloxane had the silicon-oxygen-silicon peak and the silicon-carbon peak.

That is, it can be seen that the coating layer prepared according to Comparative Example 2-1 and Comparative Example 2-2 contains silicon oxide.

In addition, it was confirmed that the coating layer prepared according to Comparative Example 2-2 further had a silicon-carbon bond compared to the coating layer according to Comparative Example 2-1.

Accordingly, it can be seen that the coating layer prepared according to Comparative Example 2-1 has a comparatively higher heat resistance than the coating layer prepared according to Comparative Example 2-2.

Referring to FIG. 17, compared to the coating layer prepared according to Comparative Example 2-1, the coating layer prepared according to Experimental Example 2-1 further includes the graphite nanoplate, which is a graphite-based material that absorbs light, Accordingly, it was confirmed that the intensity of the peak of the infrared spectrum was reduced.

18 to 19 are views showing resistance before and after heat treatment of the metal substrate structure according to the embodiment of the present invention.

18 and 19, after preparing a metal substrate structure according to Experimental Example 2-1 of the present invention and a comparative example of the metal substrate structure (Comparative Example 3), Comparative Example 3 and Experimental Example 2- The surface image and resistance of the metal substrate structure according to 1 were measured before and after heat treatment at a temperature of 400 ° C. for 3 hours.

As shown in Fig. 18 (a), it was confirmed that the copper substrate, which is a metal substrate structure according to Comparative Example 3 of the present invention, exhibits the color of copper before the heat treatment and the resistance value is measured to be 0.0 Ω. On the other hand, as shown in Fig. 19 (a), it was confirmed that the surface of the copper substrate was oxidized after heat treatment to lose the color of copper, and the resistance value was also increased to 34.7 kΩ.

However, as shown in Figure 18 (b), the metal substrate structure according to Experimental Example 2-1 of the present invention further comprises the coating layer comprising the silicon oxide and the graphite nanoplate on the surface of the copper substrate It was made to. Accordingly, it was confirmed that the electrical conductivity was reduced than the copper substrate shown in FIG. 18 (a), and the resistance value was increased to 92.8 Ω. On the other hand, as shown in Figure 19 (b), it was confirmed that the metal substrate structure according to Experimental Example 2-1 of the present invention, unlike the copper substrate shown in Figure 19 (a), does not oxidize, The resistance value was also confirmed to have a relatively low value of 0.8Ω.

20 to 21 are views showing a scanning electron microscope (SEM) image before and after heat treatment of a metal substrate structure according to an embodiment of the present invention.

20 to 21, surface images of a metal substrate structure according to Comparative Example 3 and Experimental Example 2-1 described above with reference to FIGS. 18 to 19 were photographed.

20 (a), it can be seen that the copper metal before heat treatment has a smooth surface. On the other hand, as shown in Fig. 21 (a), it was confirmed that after the heat treatment of the copper metal, spherical copper oxide was generated.

However, as shown in Figure 20 (b) and Figure 21 (b), the metal substrate structure according to Experimental Example 2-1 further comprising the coating layer on the copper substrate, regardless of before and after heat treatment, substantially It was confirmed to have the same surface.

22 is a view showing an X-ray diffraction pattern (XRD) before and after heat treatment of a metal substrate structure according to an embodiment of the present invention.

Referring to FIG. 22, as described above with reference to FIGS. 20 to 21, the metal substrate structure according to Comparative Example 3 was confirmed to exhibit a copper oxide peak unlike heat treatment after heat treatment.

In addition, it was confirmed that the copper oxide peak did not appear after the heat treatment of the metal substrate structure according to Experimental Example 2-1.

Accordingly, it can be seen that the coating layer prevents oxidation of the copper substrate by heat treatment.

23 to 24 are diagrams showing sample images before and after brine treatment of a metal substrate structure according to Comparative Example 3 and Experimental Example 2-1 of the present invention, and scanning electron microscope (SEM) images.

23 and 24, corrosion of the metal substrate structure according to Comparative Example 3 and Experimental Example 2-1 of the present invention was confirmed by salt water treatment.

23, it was confirmed that the metal substrate structure according to Comparative Example 3 ((a) of FIG. 23) was corroded by salt water treatment. On the other hand, the metal substrate structure according to Experimental Example 2-1 (Fig. 23 (b)) was not substantially confirmed corrosion by salt water treatment.

Specifically, as shown in Figure 24, the metal substrate structure according to Comparative Example 3 (FIG. 24 (a)) was confirmed that copper oxide is formed on the surface over time, after 72 hours of brine treatment It was confirmed that the size of the copper oxide was increased. On the other hand, it was confirmed that the metal substrate structure according to Experimental Example 2-1 (FIG. 24 (b)) had substantially no change in surface structure even after 72 hours of brine treatment. .

25 to 26 are views showing a sample image after the saline treatment of the metal substrate structure according to Comparative Example 4 and Experimental Example 2-1 of the present invention, and a scanning electron microscope (SEM) image.

25 and 26, a comparative example of the metal substrate structure according to Experimental Example 2-1, using an aluminum substrate, the brine treatment described above with reference to FIGS. 23 to 24 was performed.

25 (a), it was confirmed that the color of the surface of the aluminum substrate, which is a metal substrate structure according to Comparative Example 4, was changed after brine treatment. On the other hand, referring to Fig. 25 (b), as described above with reference to Fig. 23 (b), the metal substrate structure according to Experimental Example 2-1 is that the surface change is not substantially observed after the salt water treatment Confirmed.

26 (a), it was confirmed that the surface of the aluminum substrate was corroded. On the other hand, referring to (b) of FIG. 26, it can be seen that the metal substrate structure according to Experimental Example 2-1 does not substantially cause corrosion, as shown in FIG. 24 (b).

27 to 28 are views showing a sample image after sulfuric acid treatment and a scanning electron microscope (SEM) image of the metal substrate structure according to Comparative Example 4 and Experimental Example 2-1 of the present invention.

27 and 28, the metal substrate structure according to Comparative Example 4 and Experimental Example 2-1 of the present invention was confirmed whether the surface was oxidized according to sulfuric acid treatment.

As shown in FIG. 27 (a), it can be seen that the aluminum substrate is oxidized by the sulfuric acid. On the other hand, as shown in Figure 27 (b), it can be seen that the metal substrate structure according to Experimental Example 2-1 is not substantially oxidized by sulfuric acid.

Specifically, as shown in Fig. 28 (a), it was confirmed that the aluminum substrate was treated with sulfuric acid and the surface roughness was increased. On the other hand, as shown in Figure 28 (b), it was confirmed that the metal substrate structure according to Experimental Example 2-1 has a surface similar to the surface image shown in Figure 26 (b), and accordingly, the Experimental Example It can be seen that the metal substrate structure according to 2-1 is substantially not corroded by sulfuric acid.

Accordingly, it can be seen that the coating layer prevents corrosion of the copper substrate and the aluminum substrate by brine treatment and sulfuric acid.

29 to 30 are diagrams showing a polarization curve and an impedance of a metal substrate structure according to an embodiment of the present invention.

29 and 30, polarization curves and impedances of the metal substrate structures according to Comparative Example 3 and Experimental Example 2-1 were confirmed.

As shown in FIG. 29, compared to the copper substrate, which is the metal substrate structure according to Comparative Example 3, the metal substrate structure according to Experimental Example 2-1 increases the amount of current of the graphite nanoplate to 1 to 10 quills, increasing the current. It can be seen that the density value is reduced. Accordingly, it was confirmed that the metal substrate structure according to Experimental Example 2-1 had a corrosion rate about 40 times slower than that of the copper substrate.

Referring to FIG. 30, it was confirmed that the metal substrate structure according to Experimental Example 2-1 is increased in resistance by about 200 times compared to the copper substrate, and accordingly, the metal substrate structure according to Experimental Example 2-1 is the copper substrate. It can be seen that it has a corrosion efficiency of about 99% or more.

31 is a view showing the electrical conductivity and adhesion test results according to the graphite nanoplate mass ratio of the metal substrate structure according to Experimental Example 2-2 of the present invention.

Referring to Figure 31, the metal substrate structure according to Experimental Example 2-2 was confirmed that the higher the mass ratio of the graphite nanoplate, the higher the electrical conductivity. In particular, it was confirmed that when the graphite nanoplate is included in 50 parts by weight, it has the highest electrical conductivity, and when the graphite nanoplate exceeds 50 parts by weight, the value of electrical conductivity is reduced again.

On the other hand, in the metal substrate structure according to Experimental Example 2-2, it can be seen that as the mass ratio of the graphite nanoplate increases, the adhesive force decreases. That is, it can be seen that as the mass ratio of the graphite nanoplate increases, the mass ratio of the polymer in the composite coating solution decreases, and accordingly, the graphite nanoplate aggregates. Therefore, as shown in FIG. 31, when the graphite nanoplate exceeds 50 parts by weight, it can be seen that the adhesion between the metal substrate and the coating layer of the metal substrate structure according to Experimental Example 2-2 is reduced.

According to the mixing amount of the graphite nanoplate in the composite coating solution among the methods for manufacturing the metal substrate structure according to Experimental Example 2-1, to Experimental Example 2-2 of the present invention described above, chemical resistance and electrical conductivity of the metal substrate structure It was prepared in <Table 4> below.

	Weight part of graphite nanoplate in composite coating solution	Chemical resistance (1M sulfuric acid)	Electrical conductivity (S / cm)
Experimental Example 2-1	2	3000 h	0.0021
	25	1300 h	0.12
	50	500 h	12
Experimental Example 2-2	2	300 h	0.25
	25	120 h	17
	50	72 h	300

At this time, the metal substrate structure should be able to provide electrical conductivity to the metal substrate in the metal substrate structure, and accordingly, it can be seen that the graphite nanoplate is included in 10 to 50 parts by weight.

As described above, the present invention has been described in detail using preferred embodiments, but the scope of the present invention is not limited to specific embodiments, and should be interpreted by the appended claims. In addition, those skilled in the art should understand that many modifications and variations are possible without departing from the scope of the present invention.

Composite coating solution according to an embodiment of the present application, a metal substrate structure manufactured using the same, and a method of manufacturing the electrical conductivity, such as an electrically conductive material, a secondary battery material, a building material, a field for detecting destruction and deformation inside a building structure , It can be applied to various industrial fields that require oxidation resistance and corrosion resistance.

Claims (16)

1. Preparing a base solution containing a metal salt;

   Providing graphite to the base solution, and inserting anions of the metal salt into the graphite interlayer to prepare a graphite interlayer compound;

   Heat-treating the graphite interlayer compound to form expanded graphite;

   Dispersing the expanded graphite to prepare a graphite nanoplate; And

   A method of producing a composite coating solution comprising the step of preparing a composite coating solution by mixing the graphite nanoplate and the polymer.
2. According to claim 1,

   The step of heat-treating the graphite interlayer compound,

   Pyrolyzing the anion of the metal salt contained in the graphite interlayer compound;

   A method for producing a composite coating solution comprising the step of preparing the expanded graphite having an increased interlayer distance than the graphite interlayer compound, with an expansion force of a gas formed by thermal decomposition of the anions.
3. According to claim 1,

   A method of manufacturing a composite coating solution comprising increasing the amount of defects provided in the graphite nanoplate as the process temperature or process pressure of the step of heat-treating the graphite interlayer compound increases.
4. According to claim 1,

   According to the polarity of the polymer, including adjusting the amount of defects provided in the graphite nanoplate,

   The method of manufacturing a composite coating solution comprising increasing the polarity of the polymer, the amount of defects provided in the graphite nanoplate increases.
5. According to claim 1,

   The polymer is polysilazane,

   The method for producing a composite coating liquid, wherein the solvent of the composite coating liquid is a non-polar solvent.
6. According to claim 1,

   The polymer, polysiloxane (polysiloxane),

   The solvent of the composite coating solution, a method for producing a composite coating solution comprising a polar solvent.
7. According to claim 1,

   The metal salt, azide salt, carbonate, nitrate, sulfate, or a method for producing a composite coating solution containing at least one of phosphate.
8. Graphite nanoplates; And

   Contains polymers,

   With respect to the total weight of 100 parts of the graphite nanoplate and the polymer,

   The graphite nanoplate, 10 parts by weight or more and 50 parts by weight or less,

   The polymer is a composite coating solution containing 50 parts by weight or more and 90 parts by weight or less.
9. The method of claim 8,

   The polymer, a composite coating solution containing any one of an organic polymer or an inorganic polymer.
10. The method of claim 8,

    The organic polymer is a composite coating solution containing at least one of an epoxy-based polymer, a cellulose-based polymer, a vinyl-based polymer, an acrylic-based polymer, a fluorine-based polymer, an amide-based polymer, an imide-based polymer, or an acetate-based polymer.
11. The method of claim 8,

    The inorganic polymer is a composite coating solution containing at least one of polysiloxane, polysilazane, or polysilicate.
12. When the polymer of the composite coating solution according to claim 8 is polysilazane,

    A coating method using a composite coating solution comprising coating the composite coating solution on a metal substrate by any one of a spray coating method and a spin coating method.
13. When the polymer of the composite coating solution according to claim 8 is polysiloxane,

    A coating method using a composite coating solution comprising coating the composite coating solution on a metal substrate by any one of a bar coating method and a doctor blast coating method.
14. Claim 12 or 13 comprises the step of preparing a coating layer by hot pressing the pre-coating layer prepared by any one of the coating method,

    A coating method using a composite coating solution comprising reducing the process pressure as the amount of the graphite nanoplate increases in the preliminary coating layer.
15. Metal substrates; And

    Is disposed on the metal substrate, comprises a graphite nanoplate, and a coating layer comprising silicon oxide,

    The coating layer, a metal substrate structure that does not contain a silicon-carbon bond in the IR analysis method, and includes a higher oxidation resistance and stone resistance than the metal substrate.
16. The method of claim 15,

    A metal substrate structure comprising increasing corrosion resistance as the amount of the silicon oxide in the coating layer increases.

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