Preparation method of corrosion-resistant conductive material and application of corrosion-resistant conductive material in automobile primer

Abstract

The invention belongs to the technical field of conductive material preparation, and particularly relates to a preparation method of a corrosion-resistant conductive material and application of the corrosion-resistant conductive material in the aspect of automobile primer. Rutile phase titanium dioxide is used as a base material, band gaps of titanium dioxide are reduced through coated modified aluminum oxide, then graphene is compounded through an ultrasonic method, and the corrosion-resistant conductive material is obtained. And finally, centrifuging, drying and grinding to obtain a target product. According to the application in the aspect of automobile primer, polyvinylidene fluoride and N-methyl pyrrolidone are stirred under the constant-temperature water bath condition to prepare a glue solution; and dispersing a corrosion-resistant conductive material into the glue solution, stirring to obtain slurry, and uniformly spraying the slurry on the automobile base material foamed nickel through a spray gun. The method is easy to operate, low in cost and long in service life, electrostatic discharge harm can be inhibited, environmental pollution is prevented, the conductivity of the material is improved, and meanwhile the problem that the surface of the material is prone to corrosion can be solved.

Description

Technical Field

[0001] This invention belongs to the technical field of conductive material preparation, specifically to a method for preparing a corrosion-resistant conductive material and its application in automotive primers. This method helps improve the material's conductivity while addressing the issue of surface corrosion, thereby reducing the hazards of electrostatic discharge and alleviating environmental pollution caused by material corrosion. Background Art

[0002] Conductive materials are functional materials used on non-conductive substrates to enable them to conduct current and dissipate static charge. Most commercially available materials have improved conductivity after modification, but their performance is unstable and easily affected by temperature and humidity. They also have significant disadvantages such as high preparation cost, complex process, susceptibility to corrosion, and lack of environmental friendliness. As an important inorganic raw material, rutile phase TiO2 has excellent properties such as high temperature resistance, low temperature resistance, corrosion resistance, high strength, and low specific gravity. It is widely used in military aviation, aerospace, navigation, machinery, chemical industry, seawater desalination and other aspects. However, pure rutile phase TiO2 as a conductive coating not only has poor light absorption and stability, but also has relatively weak antibacterial properties.

[0003] Conductive fillers are conductive carriers for composite conductive coatings. In the 1990s, the United States, Japan, Germany and other countries developed metal oxide-based conductive fillers, mainly antimony-doped tin oxide, zinc oxide, antimony trioxide, etc., and some products have been commercialized. However, these traditional conductive fillers not only have unstable conductive properties and are easily affected by temperature and humidity, but also have significant disadvantages such as high preparation costs and lack of environmental friendliness.

[0004] Conductivity refers to a material's ability to conduct an electric current, typically described as conductivity or resistivity. High conductivity means a material can effectively conduct current, which is crucial in many applications, such as electronics, circuit boards, and anti-static coatings. Corrosion resistance refers to a material's ability to withstand the effects of corrosive environments, such as chemicals, moisture, and salt water. Materials with high corrosion resistance maintain their performance and appearance, extending their service life and reducing maintenance costs. Summary of the Invention

[0005] The present invention aims to overcome the shortcomings of the existing technology and provide a method for preparing a corrosion-resistant conductive material that is simple to operate, low in cost, has a long service life, can suppress the hazards of electrostatic discharge, prevent environmental pollution, and improve the conductive properties of the material while solving the problem of the material surface being easily corroded.

[0006] Another object of the present invention is to provide a method for preparing a corrosion-resistant conductive material and to use the product obtained in automobile primer.

[0007] To solve the above-mentioned technical problems, the present invention is achieved as follows:

[0008] A method for preparing a corrosion-resistant conductive material comprises the following steps: using rutile phase titanium dioxide as a base material, coating the rutile phase titanium dioxide with modified alumina, ultrasonically compounding the rutile phase titanium dioxide with graphene, and finally centrifuging, washing, drying and grinding to obtain a target product.

[0009] As a preferred solution, the method for preparing the corrosion-resistant conductive material comprises the following specific steps:

[0010] (1) Alumina, boric acid and nanodiamonds are mixed and then ball-milled to obtain modified alumina powder;

[0011] (2) mixing the product obtained in step (1) with rutile phase titanium dioxide and ball milling the mixture again to obtain a powder of modified alumina-coated titanium dioxide;

[0012] (3) adding the product obtained in step (2) to a cetyltrimethylammonium bromide solution under stirring;

[0013] (4) adding the ultrasonically dispersed graphene to the product obtained in step (3) and performing ultrasonic dispersion again;

[0014] (5) The product obtained in step (4) is centrifuged, and then washed twice with anhydrous ethanol and distilled water respectively and centrifuged again. The centrifuged product is then dried and ground to obtain the desired product.

[0015] Furthermore, in step (1), 2 g of aluminum oxide, 4 g of nanodiamond and 2 g of boric acid are put into a ball mill for ball milling, the ball mill speed is set to 50 Or / min, and the ball milling time is set to 5 h.

[0016] Furthermore, in the step (2), the modified alumina powder and rutile phase titanium dioxide are mixed in a mass ratio of 1:1 to 3 and then placed in a ball mill for ball milling again. The ball mill speed is set to 300 r / min and the ball milling time is set to 3 h.

[0017] Furthermore, in step (3), 0.2 g of hexadecyltrimethylammonium bromide was dissolved in 30 mL of deionized water in a constant temperature water bath at 40° C., 1 g of the product obtained in step (2) was weighed, and slowly added to the above hexadecyltrimethylammonium bromide solution under constant temperature stirring.

[0018] Furthermore, in the step (4), 0.06-0.07 g of graphene is dissolved in 20 mL of deionized water and ultrasonically dispersed for 1 hour to obtain a graphene suspension; the solution obtained in step (3) is slowly added dropwise to the graphene suspension, and then ultrasonicated again for 1 hour.

[0019] Furthermore, in step (5), the product obtained in step (4) is centrifuged, then washed twice with anhydrous ethanol and deionized water respectively, placed in an oven at 80° C. and dried for 12 hours, and the dried product is ground to obtain the target product.

[0020] The product obtained by the preparation method of the corrosion-resistant conductive material is used in automobile primer. Polyvinylidene fluoride and nitrogen methyl pyrrolidone are stirred in a constant temperature water bath to prepare a glue solution; the corrosion-resistant conductive material is dispersed in the glue solution and stirred to obtain a slurry, and then the slurry is evenly sprayed on the automobile substrate foam nickel through a spray gun.

[0021] Alumina is a commonly used material. By coating titanium dioxide, it can effectively improve the stability, optical properties, catalytic activity and weather resistance of the coating. In addition, the use of ultrasonic composite graphene as a conductive agent not only enhances the electrical conductivity of the composite material, but also greatly improves the corrosion resistance of the coating and enhances its protection efficiency. The present invention mainly uses planetary ball milling as the main experimental method, and uses ultrasonic composite method to assist in the preparation of composite materials. The activity of alumina purchased on the market is relatively low. After being ball milled in a ball mill at a suitable speed and time, it can play the role of modified alumina. Not only will the crystal form of alumina change, becoming an α-type alumina that is more suitable for modifying titanium dioxide, but the active sites on its surface will also increase. The above material processing method is to prepare the composite material by ball milling, but the ball mill parameter setting is complicated. The ball milling time and ball milling speed are both single factors that should be considered, and the ratio of alumina and titanium dioxide, as well as the ball milling time and speed of the two cannot be ignored.

[0022] The present invention uses rutile titanium dioxide as a base material. The band gap of titanium dioxide is reduced by coating it with modified alumina. Graphene is then composited with it using an ultrasonic method. Finally, the process is centrifuged, dried, and ground to obtain the desired product. Experiments have demonstrated that the present invention not only significantly improves the electrical conductivity of the composite material, thereby reducing the hazards of electrostatic discharge, but also addresses the problem of the material's surface being susceptible to corrosion in air, mitigating the risk of environmental pollution following corrosion. The present invention not only significantly enhances the composite material's electrical conductivity, reducing the resistivity to below 0.1 Ω·cm, but also significantly improves the coating's protective efficiency, raising it to over 95%. Even after 10 days of immersion in salt water, the coating maintains an efficiency of over 85%. Furthermore, the preparation method of the present invention does not produce highly toxic intermediates, providing a material with excellent performance for applications in composite conductive coatings.

[0023] Compared with the prior art, the present invention has the following characteristics:

[0024] 1. The present invention mainly adopts the ball milling method, the planetary ball milling method, which can quickly and effectively achieve crushing and mixing, and is more suitable for large-scale application in laboratories and industrial production; the aluminum oxide used to modify titanium dioxide is low in price and adaptable to industrial production;

[0025] 2. The present invention uses ultrasonic method to help remove surface attachments, oxides, etc., improve the cleanliness and activity of the material surface. In addition, it can also break up and disperse particles, helping to improve the uniformity and stability of the material.

[0026] 3. The present invention has a simple operation method and excellent electrical conductivity and corrosion resistance. It not only has the advantages of low price, simple operation and long service life, but can also be used in photovoltaic power generation brackets, petrochemical equipment and aerospace equipment. The application range of the product is relatively wide.

[0027] 4. The present invention adopts ball milling method to pre-treat alumina, which can not only improve the surface activity and specific surface area of alumina, improve particle morphology and dispersibility, but also enhance the chemical stability of alumina and improve mechanical properties.

[0028] 5. The present invention can be widely used in the fields of electronic information, aerospace, marine engineering, automobile industry, chemical industry, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be described in detail below through specific examples. These examples are provided in order to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art. As mentioned throughout the specification and claims, "including" or "comprising" is an open-ended term and is interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the present invention. The scope of protection of the present invention shall be determined by the appended claims. Unless otherwise specified, the various reagents and materials used in the present invention can be purchased from the market.

[0030] Figure 1 This is the SEM spectrum of the alumina-coated titanium dioxide composite graphene material of the present invention.

[0031] Figure 2 This is a test of the sedimentation effect of the modified alumina of the present invention.

[0032] Figure 3 This is the Tafel corrosion curve test of the alumina-coated titanium dioxide composite graphene material of the present invention. DETAILED DESCRIPTION

[0033] Example 1

[0034] (1) Take 2 g of aluminum oxide, 2 g of nanodiamond, and 2 g of boric acid, put them into a planetary ball mill and mill them to obtain modified aluminum oxide; the ball milling speed is set to 500 r / min, and the ball milling time is set to 5 h.

[0035] (2) The ball-milled product was subjected to XRD testing, and it was found that the alumina was not successfully modified.

[0036] Example 2

[0037] (1) 2 g of alumina, 6 g of nanodiamond, and 2 g of boric acid were placed in a planetary ball mill and milled to obtain modified alumina; the ball milling speed was set to 500 r / min and the ball milling time was set to 5 h.

[0038] (2) The ball milled product was subjected to XRD testing and dispersion test, and it was found that the alumina modification effect was not good. Figure 2 As shown in the figure, excessive diamond will reduce the dispersibility of modified alumina.

[0039] Example 3

[0040] (1) 2 g of alumina, 4 g of nanodiamond, and 2 g of boric acid were placed in a planetary ball mill and milled to obtain modified alumina; the ball milling speed was set to 500 r / min and the ball milling time was set to 5 h.

[0041] (2) The ball-milled product was subjected to XRD testing, and it was found that the alumina modification was successful.

[0042] (3) Collect the product in step (1), take 1 g of rutile phase titanium dioxide and 4 g of modified alumina obtained in step (1), and put them into the planetary ball mill again. The ball milling speed is 300 r / min and the ball milling time is set to 3 h.

[0043] (4) The product in step (3) was collected, 0.2 g of CTAB was weighed and added to 30 mL of deionized water, dissolved in a water bath at 40° C., and 1 g of the product in step (3) was added thereto under stirring to obtain solution (4).

[0044] (5) 0.06 g of graphene was dissolved in 20 mL of deionized water and ultrasonically dispersed for 1 hour to obtain a graphene suspension. Solution (4) was then slowly dripped into the graphene suspension, and the resulting solution was ultrasonically dispersed for 1 hour.

[0045] (6) The obtained solid product was centrifuged and washed twice with anhydrous ethanol and distilled water respectively, placed in an oven and dried at 80° C. for 12 hours, and the dried product was ground to obtain a titanium dioxide-doped aluminum oxide composite graphene composite coating.

[0046] (7) The product collected in step (6) is pressed into a sheet and its resistivity is measured using a four-probe tester. The sample is then made into a slurry and coated on nickel foam. The Tafel curve is measured using an electrochemical workstation. The protective efficiency of the coating can be calculated based on the Tafel curve.

[0047] The experimental results show that the Al2O3@T / G composite material has a good coating state, a fast electrochemical response speed, and a uniform graphene composite. The resistivity of the Al2O3@T / G composite material prepared above was measured by a four-probe tester to be 1.59Ω·cm. Figure 1 As shown in the figure, the corrosion current of Al2O3@T / G composite material was measured by electrochemical workstation to be -4.044A / cm2 and the corrosion potential was -0.037V. The protection efficiency was calculated to be 85.78%.

[0048] Example 4

[0049] (1) 2 g of alumina, 4 g of nanodiamond, and 2 g of boric acid were placed in a planetary ball mill and milled to obtain modified alumina; the ball milling speed was set to 50 Or / min, and the ball milling time was set to 5 h.

[0050] (2) Collect the product in step (1), take 3 g of rutile phase titanium dioxide and 4 g of modified alumina obtained in step (1), and put them into the planetary ball mill again. The ball milling speed is 300 r / min and the ball milling time is set to 3 h.

[0051] (3) The product in step (2) was collected, 0.2 g of CTAB was weighed and added to 30 mL of deionized water, dissolved in a water bath at 40° C., and 1 g of the product in step (2) was added thereto under stirring to obtain solution (3).

[0052] (4) 0.06 g of graphene was dissolved in 20 mL of deionized water and ultrasonically dispersed for 1 hour to obtain a graphene suspension. Solution (3) was then slowly dripped into the graphene suspension, and the resulting solution was ultrasonically dispersed for 1 hour.

[0053] (5) The obtained solid product was centrifuged and washed twice with anhydrous ethanol and distilled water respectively, placed in an oven and dried at 80° C. for 12 hours, and the dried product was ground to obtain a titanium dioxide-doped aluminum oxide composite graphene composite coating.

[0054] Table 1 Comparison of the contents of components in Example 3 and Example 4

[0055] Example 3 Example 4 Alumina: nanodiamond: boric acid = 1:2:1 Alumina: nanodiamond: boric acid = 1:2:1 Titanium dioxide: modified alumina = 1:1 Titanium dioxide: modified alumina = 3:1 Graphene addition 6% Graphene addition 6%

[0056] (6) The product collected in step (5) is pressed into a sheet and its resistivity is measured using a four-probe tester. The sample is then made into a slurry and coated on nickel foam. The Tafel curve is measured using an electrochemical workstation. The protective efficiency of the coating can be calculated based on the Tafel curve.

[0057] Table 2 Comparison of the effects of Example 3 and Example 4

[0058] Example 3 Example 4 Average resistivity: 1.59Ω·cm Average resistivity: 1.01Ω·cm Protection efficiency: 89.8% Protection efficiency: 90.9%

[0059] Example 5

[0060] (1) 2 g of alumina, 4 g of nanodiamond, and 2 g of boric acid were placed in a planetary ball mill and milled to obtain modified alumina; the ball milling speed was set to 500 r / min and the ball milling time was set to 5 h.

[0061] (2) Collect the product in step (1), take 2 g of rutile phase titanium dioxide and 4 g of modified alumina obtained in step (1), and put them into the planetary ball mill again at a ball milling speed of 300 r / min and a ball milling time of 3 h.

[0062] (3) The product in step (2) was collected, 0.2 g of CTAB was weighed and added to 30 mL of deionized water, dissolved in a water bath at 40° C., and 1 g of the product in step (2) was added thereto under stirring to obtain solution (3).

[0063] (4) 0.06 g of graphene was dissolved in 20 mL of deionized water and ultrasonically dispersed for 1 hour to obtain a graphene suspension. Solution (3) was then slowly dripped into the graphene suspension, and the resulting solution was ultrasonically dispersed for 1 hour.

[0064] (5) The obtained solid product was centrifuged and washed twice with anhydrous ethanol and distilled water respectively, placed in an oven and dried at 80° C. for 12 hours, and the dried product was ground to obtain a titanium dioxide-doped aluminum oxide composite graphene composite coating.

[0065] Table 3 Comparison of the contents of each component in Examples 3-5

[0066]

[0067] (6) The product collected in step (5) is pressed into a sheet and its resistivity is measured using a four-probe tester. The sample is then made into a slurry and coated on nickel foam. The Tafel curve is measured using an electrochemical workstation. The protective efficiency of the coating can be calculated based on the Tafel curve.

[0068] Table 4 Comparative table of effects of Examples 3-5

[0069]

[0070] Example 6

[0071] (1) 2 g of alumina, 4 g of nanodiamond, and 2 g of boric acid were placed in a planetary ball mill and milled to obtain modified alumina; the ball milling speed was set to 500 r / min and the ball milling time was set to 5 h.

[0072] (2) Collect the product in step (1), take 2 g of rutile phase titanium dioxide and 4 g of modified alumina obtained in step (1), and put them into the planetary ball mill again at a ball milling speed of 300 r / min and a ball milling time of 3 h.

[0073] (3) The product in step (2) was collected, 0.2 g of CTAB was weighed and added to 30 mL of deionized water, dissolved in a water bath at 40° C., and 1 g of the product in step (2) was added thereto under stirring to obtain solution (3).

[0074] (4) 0.07 g of graphene was dissolved in 20 mL of deionized water and ultrasonically dispersed for 1 hour to obtain a graphene suspension. Solution (3) was then slowly dripped into the graphene suspension, and the resulting solution was ultrasonically dispersed for 1 hour.

[0075] (5) The obtained solid product was centrifuged and washed twice with anhydrous ethanol and distilled water respectively, placed in an oven and dried at 80° C. for 12 hours, and the dried product was ground to obtain a titanium dioxide-doped aluminum oxide composite graphene composite coating.

[0076] Table 5 Comparative table of the contents of each component in Examples 3-6

[0077]

[0078]

[0079] (6) The product collected in step (5) is pressed into a sheet and its resistivity is measured using a four-probe tester. The sample is then made into a slurry and coated on nickel foam. The Tafel curve is measured using an electrochemical workstation. The protective efficiency of the coating can be calculated based on the Tafel curve.

[0080] Table 6 Comparative table of effects of Examples 3-6

[0081]

[0082] Example 7

[0083] (1) 2 g of alumina, 4 g of nanodiamond, and 2 g of boric acid were placed in a planetary ball mill and milled to obtain modified alumina; the ball milling speed was set to 500 r / min and the ball milling time was set to 5 h.

[0084] (2) Collect the product in step (1), take 2 g of rutile phase titanium dioxide and 4 g of modified alumina obtained in step (1), and put them into the planetary ball mill again at a ball milling speed of 500 r / min and a ball milling time of 5 h.

[0085] (3) The product in step (2) was collected, 0.2 g of CTAB was weighed and added to 30 mL of deionized water, dissolved in a water bath at 40° C., and 1 g of the product in step (2) was added thereto under stirring to obtain solution (3).

[0086] (4) 0.07 g of graphene was dissolved in 20 mL of deionized water and ultrasonically dispersed for 1 hour to obtain a graphene suspension. Solution (3) was then slowly dripped into the graphene suspension, and the resulting solution was ultrasonically dispersed for 1 hour.

[0087] (5) The obtained solid product was centrifuged and washed twice with anhydrous ethanol and distilled water respectively, placed in an oven and dried at 80° C. for 12 hours, and the dried product was ground to obtain a titanium dioxide-doped aluminum oxide composite graphene composite coating.

[0088] Table 7 Comparative table of the contents of each component in Examples 3-7

[0089]

[0090] (6) The product collected in step (5) was pressed into a sheet and its resistivity was measured using a four-probe tester. The sample was then made into a slurry and coated on nickel foam, and its impedance spectrum was measured using an electrochemical workstation. Figure 3 And Tafel curve, the protective efficiency of the coating can be calculated according to the Tafel curve.

[0091] Table 8 Comparative table of effects of Examples 3-7

[0092]

[0093] Experimental results

[0094] The alumina-coated titanium dioxide composite graphene material prepared in Example 7 was subjected to scanning electron microscopy, and the results are as follows: Figure 1 As shown in the figure, it can be seen that the prepared composite material has a graphene sheet structure and metal oxide-coated titanium dioxide particles, and the degree of metal oxide coating is good.

[0095] The electrical conductivity and corrosion resistance of the materials of Examples 3 to 7 were compared, and it was found that the electrical conductivity and corrosion resistance of Example 5 were the highest, and the protection efficiency of the coating could still be maintained above 85% after immersion in 3.5% wt sodium chloride for 10 days, indicating that the corrosion resistance of the coating is still very good after long-term immersion in concentrated salt water.

[0096] It can be understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents to achieve the same technical effects; as long as the use requirements are met, they are within the scope of protection of the present invention.

Claims

1. A method for preparing a corrosion-resistant conductive material, characterized in that: The method uses rutile phase titanium dioxide as a base material, uses modified alumina to coat the rutile phase titanium dioxide, and then ultrasonically composites it with graphene. Finally, it is centrifuged, washed, dried and ground to obtain the target product.

2. The method for preparing the corrosion-resistant conductive material according to claim 1, characterized in that: The specific steps include: (1) Alumina, boric acid and nanodiamonds are mixed and then ball-milled to obtain modified alumina powder; (2) mixing the product obtained in step (1) with rutile phase titanium dioxide and ball milling the mixture again to obtain a powder of modified alumina-coated titanium dioxide; (3) adding the product obtained in step (2) to a cetyltrimethylammonium bromide solution under stirring; (4) adding the ultrasonically dispersed graphene to the product obtained in step (3) and performing ultrasonic dispersion again; (5) The product obtained in step (4) is centrifuged, then washed twice with anhydrous ethanol and distilled water respectively and centrifuged again. The centrifuged product is then dried and ground to obtain the target product.

3. The method for preparing the corrosion-resistant conductive material according to claim 2, wherein: In the step (1), 2 g of aluminum oxide, 4 g of nanodiamond and 2 g of boric acid are put into a ball mill for ball milling. The ball mill speed is set to 500 r / min and the ball milling time is set to 3 to 5 h.

4. The method for preparing the corrosion-resistant conductive material according to claim 3, wherein: In the step (2), the modified alumina powder and rutile phase titanium dioxide are mixed in a mass ratio of 1:1 to 3 and then placed in a ball mill for ball milling again. The ball mill speed is set to 300 r / min and the ball milling time is set to 3 h.

5. The method for preparing the corrosion-resistant conductive material according to claim 4, characterized in that: In the step (3), 0.2 g of hexadecyltrimethylammonium bromide was dissolved in 30 mL of deionized water in a constant temperature water bath at 40° C., 1 g of the product obtained in the step (2) was weighed, and slowly added to the above hexadecyltrimethylammonium bromide solution under constant temperature stirring.

6. The method for preparing the corrosion-resistant conductive material according to claim 5, characterized in that: In the step (4), 0.06-0.07 g of graphene is dissolved in 20 mL of deionized water and ultrasonically dispersed for 1 hour to obtain a graphene suspension; the solution obtained in step (3) is slowly added dropwise to the graphene suspension, and then ultrasonicated again for 1 hour.

7. The method for preparing the corrosion-resistant conductive material according to claim 6, characterized in that: In the step (5), the product obtained in the step (4) is centrifuged, and then washed twice with anhydrous ethanol and deionized water respectively, and dried in an oven at 80° C. for 12 h. The dried product is ground to obtain the target product.

8. Use of the product obtained by the method for preparing the corrosion-resistant conductive material according to any one of claims 1 to 7 in automobile primer, characterized in that: Polyvinylidene fluoride and nitrogen methyl pyrrolidone are stirred in a constant temperature water bath to prepare a glue solution; a corrosion-resistant conductive material is dispersed in the glue solution and stirred to obtain a slurry, which is then evenly sprayed on the automobile substrate foam nickel through a spray gun.

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