Conductive anticorrosive coating on surface of cable armored aluminum material and preparation method of conductive anticorrosive coating

Abstract

The invention discloses a cable armored aluminum surface conductive anticorrosive coating and a preparation method thereof.The preparation method comprises the steps that firstly, fluorine-doped boron nitride nanosheets are prepared through high-temperature calcination of a precursor, polyaniline nanorods are constructed on the surfaces of the fluorine-doped boron nitride nanosheets through an interface induction in-situ polymerization method, F-BN-PANI composite filler of a sheet-rod synergistic structure is formed, and the conductive anticorrosive coating is prepared. And finally, introducing the F-BN-coated PANI composite filler into a flexible epoxy resin system, and uniformly coating the F-BN-coated PANI composite filler on the surface of an armored aluminum material in a traction dipping manner to prepare a functional composite coating with high conductivity, excellent corrosion resistance and good flexibility. The coating is suitable for structural protection and anti-corrosion coating of cable armored monofilaments, and has good industrial application prospects.

Description

Technical Field

[0001] The invention belongs to the field of conductive anti-corrosion coatings, and particularly relates to a conductive anti-corrosion coating on the surface of a cable armored aluminum material and a preparation method thereof. Background Art

[0002] Aluminum strip is widely used in cable armor due to its light weight, low price, and ease of processing, making it a key material choice for achieving both lightweight and high-strength cable systems. However, aluminum's inherent surface passivation, high oxide film resistance, and low electrical conductivity prevent it from establishing a continuous and effective grounding protection path during service. It also struggles to meet electrical requirements such as fault current conduction, electromagnetic signal shielding, and cable interference suppression. Furthermore, in humid, high-salt, or acidic or alkaline environments, the aluminum surface is more susceptible to electrochemical corrosion, seriously impacting the armor's protective stability and service life.

[0003] The Chinese patent "A conductive anti-corrosion coating process for aluminum flow field plates" (application number: 201710470033.6, application publication number: CN 107425209 A, publication date: 2017.12.01) is obtained by placing the pre-treated aluminum into a graphene oxide aqueous solution containing tetrahydroxyaluminate ions, and then immersing it in a sodium hypophosphite solution for treatment, washing it with water and drying it at room temperature to obtain a conductive anti-corrosion coating that meets the requirements of high corrosion resistance, high conductivity and low contact resistance of aluminum flow field plates in a fuel cell environment. Although the impregnation method has the advantage of simple processing, this solution has obvious environmental risks. The impregnation method is very likely to produce chemical waste liquid, increase the subsequent treatment process, and increase the process cost. Secondly, the coating prepared by chemical impregnation with an aqueous solution in this invention is relatively thin, and the wear resistance of the coating is greatly reduced, which reduces its service life in practical applications.

[0004] The Chinese patent "Conductive Anti-corrosion Coating, Preparation Method and Application" (application number: CN202210702259.5, application date: 2017.12.01) can effectively improve the corrosion resistance and conductivity of the coating by combining organic titanium polymer, polyphenol oxide resin, toughening agent, conductive agent and curing agent. However, the proportion of filler added in the coating is relatively high, which greatly increases the cost of the conductive anti-corrosion coating and reduces the adhesion of the coating.

[0005] The Chinese patent "A Method for Preparing a Conductive Anti-Corrosion Coating on a Magnesium Alloy Micro-Arc Oxidation Layer" (Application Number: 202210506015.X, Application Date: May 11, 2022) prepares a PPy conductive material or PPy / graphene conductive composite coating on a micro-arc oxidation surface. The coating exhibits excellent corrosion resistance and electrical conductivity, but its preparation steps are relatively complex. Furthermore, spin coating can only be applied to simple, planar surfaces, which cannot meet the conductive protection requirements of complex structural components.

[0006] Zhang Yan et al. (Zhang Yan, Kang Hailan, Fang Qinghong. Preparation and performance of conductive anti-corrosion coatings using eucommia gum / carbon nanotube-modified epoxy resin [J]. Synthetic Rubber Industry, 2022, 45(01): 54-59) prepared conductive anti-corrosion coatings using eucommia gum (EUG) and epoxy resin (E-51) as coating matrices and carbon nanotubes as conductive fillers. Although the introduction of eucommia gum and carbon nanotubes improved the brittleness and poor conductivity of epoxy coatings to a certain extent, carbon nanotubes, as one-dimensional nanomaterials, do not have advantages in corrosion resistance. Carbon nanotubes are very easy to agglomerate, not only failing to play the barrier role that coating fillers have, but their dispersion problems will also affect the original performance of the coating. Summary of the Invention

[0007] To overcome the above problems, the present invention proposes a conductive anti-corrosion coating on the surface of cable armored aluminum material and a preparation method thereof. By constructing a "sheet-rod synergistic" functional filler structure and introducing a flexible modified epoxy matrix, the coating on the surface of the aluminum strip has excellent conductivity, corrosion resistance and mechanical flexibility, adapting to the repeated winding and service environment of the armor structure, and effectively improving the overall performance and service life of the cable.

[0008] In order to achieve the above object, the technical solution adopted by the present invention is:

[0009] A method for preparing a conductive anti-corrosion coating on the surface of a cable armored aluminum material is specifically implemented according to the following steps:

[0010] Step 1: Preparation of F-doped boron nitride nanosheets

[0011] The boron source, nitrogen source and fluorine source are dissolved in a solvent in a molar ratio, heated and stirred to dissolve, and naturally cooled and recrystallized after complete dissolution. The precursor obtained by recrystallization is dried, calcined and ground to obtain F-doped boron nitride nanosheets, which are labeled as F-BNNS.

[0012] Step 2: Preparation of polyaniline-coated F-BN composite filler by in-situ polymerization

[0013] The F-BN NS obtained in step 1 is dispersed in an ethanol solution to obtain a mixed solution, an acidic solution is added to the mixed solution to keep the mixed solution acidic, and then aniline and a polymerization initiator are added to the mixed solution in sequence. The mixed solution is placed in an ice bath, and aniline is adsorbed and directionally polymerized to form polyaniline nanorods in situ on the surface of the F-BN NS. The polyaniline nanorods are then repeatedly rinsed with deionized water and ethanol, filtered until the pH is neutral, and dried at 60°C to obtain a polyaniline-coated F-BN composite filler, which is labeled as F-BN@PANI.

[0014] Step 3, preparation of F-BN@PANI conductive anti-corrosion coating

[0015] The F-BN@PANI obtained in step 2 is added to the epoxy resin and stirred, and then a curing compounding agent, an organic solvent, a defoaming agent, and a dispersant are added and stirred again to form a homogeneous emulsion. The mixture is vacuum degassed, and then the armored aluminum substrate is drawn and impregnated in the homogeneous emulsion, and dried by blast heating to obtain the F-BN@PANI conductive anti-corrosion coating on the surface of the armored aluminum material.

[0016] Furthermore, the boron source described in step 1 is any one or more of boron oxide, borax and boric acid, the nitrogen source is any one or more of urea, guanidine hydrochloride and melamine, the fluorine source is any one of triethylamine trihydrofluoride, sodium fluoride, potassium fluoride and ammonium fluoride, and the molar ratio of the boron source, the nitrogen source and the fluorine source is 1:2~5.5:0.1~0.3; the solvent is composed of deionized water and n-propanol or anhydrous ethanol, the volume ratio of deionized water to alcohol is 0~1:1, and the solvent is 200 mL; the calcination temperature is 900~1300℃, and the calcination time is 4~8h.

[0017] Furthermore, in step 2, the acidic solution is any one or more of hydrochloric acid, sulfuric acid, dodecylsulfonic acid and dodecylbenzenesulfonic acid, with a concentration of 1 mol / L; the polymerization initiator is any one or more of ammonium persulfate, benzoyl peroxide, ferric chloride and manganese dioxide; and the polymerization time is 18 to 24 hours.

[0018] Furthermore, in step 2, the dispersed mass of F-BN NS is 0.1-0.5 g, the mass fraction of the ethanol solution is 30-60 wt%, the volume is 300-500 ml, the volume of the acidic solution added is 5-8.5 mL, the amount of aniline added is 1-2.5 mL, and the amount of the polymerization initiator added is 1.2-3.6 g.

[0019] Furthermore, in step 3, the amount of F-BN@PANI added is 3.0-10.0wt%; the amount of epoxy resin and compound curing agent added is 59-66wt%, wherein the ratio between epoxy resin and curing compound is 2:1-1.5; the organic solvent is any one of DMAc, ethanol, and methanol, and the addition amount is 30wt%; the curing compound is any one of T-31 and polyamide 650 and one or more of polyetheramine D400, T403 and T-99, mixed in a mass ratio of 1:0.18-0.4; the defoamer is any one of BYK-057, BYK-088, TEGO Airex902W or DAPRO DF 900, and the addition amount is 0.5wt%; the dispersant is selected from BYK-9076, EFKA 4046 or Disperbyk-110, etc., with an addition amount of 0.5wt%, wherein the sum of the mass percentages of F-BN@PANI, epoxy resin and compound curing agent, organic solvent, defoaming agent and dispersant is 100wt%.

[0020] The conductive anti-corrosion coating is prepared according to the above-mentioned method for preparing a conductive anti-corrosion coating on the surface of cable armored aluminum material.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention grows polyaniline nanorods on the surface of F-BN through interface-induced in-situ polymerization to form a composite structural filler, achieving directional coating and cooperative assembly of conductive polymers on the surface of two-dimensional sheets, and constructing a "sheet-rod cooperative conductive network" with high order and structural stability in the epoxy coating system. This structure can effectively construct a penetrating electron migration pathway in the epoxy matrix to achieve efficient lateral electron transmission; it increases the ion transmission path and constructs a multi-faceted longitudinal ion barrier system, which significantly improves the conductivity and corrosion resistance of the coating. In addition, the use of a compound curing agent to achieve dual optimization of epoxy resin flexibility regulation and chemical cross-linking gives the coating excellent flexibility and stress release ability, which can effectively adapt to the repeated bending and winding stress generated in the process of cable aluminum armoring, and ensure the continuity of the coating and long-term service stability. It shows excellent structural integration and application promotion potential, and is suitable for the functional coating and corrosion protection of cable armor wire. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the conductive anti-corrosion coating on the surface of the cable armored aluminum material prepared by the present invention;

[0024] In the figure, 1-armored aluminum, 2-conductive anti-corrosion coating, 3-polyaniline-coated F-BN composite filler. DETAILED DESCRIPTION

[0025] The present invention will be described in detail below with reference to specific embodiments and the accompanying drawings.

[0026] Step 1: Preparation of F-doped boron nitride nanosheets (F-BN NS)

[0027] The boron source, nitrogen source and fluorine source are dissolved in 200 mL of a solvent consisting of deionized water and n-propanol or anhydrous ethanol at a molar ratio of 1:2-5.5:0.1-0.3, heated and stirred to dissolve, and naturally cooled and recrystallized after complete dissolution. The recrystallized precursor is dried and calcined in a tube furnace at a temperature of 900-1300°C under a N2 atmosphere for 4-8 hours. The final product is ground uniformly and sealed for storage to obtain F-doped boron nitride nanosheets, labeled as F-BNNS;

[0028] The boron source is any one or more of boron oxide, borax and boric acid; the nitrogen source is any one or more of urea, guanidine hydrochloride and melamine; the fluorine source is any one of triethylamine trihydrofluoride, sodium fluoride, potassium fluoride and ammonium fluoride; and the volume ratio of deionized water to alcohol is 0 to 1:1.

[0029] Step 2: Preparation of polyaniline-coated F-BN composite filler by in-situ polymerization

[0030] 0.1-0.5 g of the F-BN NS obtained in step 1 is dispersed in 300-500 ml of a 30-60 wt% ethanol solution by high-speed shear dispersion to obtain a stably dispersed mixed solution, 5-8.5 mL of an acidic solution is added to the mixed solution to keep the mixed solution acidic, and then 1-2.5 mL of aniline and 1.2-3.6 g of a polymerization initiator are added to the mixed solution in sequence. The mixed solution is placed in an ice bath, and the aniline monomer is preferentially adsorbed and directionally polymerized for 18-24 hours to form polyaniline nanorods in situ on the F-BN surface. The mixture is then repeatedly rinsed and filtered with deionized water and ethanol until the pH is neutral, and dried at 60° C. to obtain a polyaniline-coated F-BN composite filler, labeled F-BN@PANI;

[0031] The acidic solution is any one or more of hydrochloric acid, sulfuric acid, dodecylsulfonic acid and dodecylbenzenesulfonic acid, with a concentration of 1 mol / L; the polymerization initiator is any one or more of ammonium persulfate, benzoyl peroxide, ferric chloride and manganese dioxide; and the initiator is any one or more of ammonium persulfate, benzoyl peroxide, ferric chloride and manganese dioxide.

[0032] Step 3, preparation of F-BN@PANI conductive anti-corrosion coating

[0033] 3.0 to 10.0 wt% of the F-BN@PANI obtained in step 2 is added to the epoxy resin, stirred at a speed of 600 rpm for 40 minutes, and then a curing compound, an organic solvent, a defoaming agent and a dispersant are added and stirred again for 20 minutes to form a homogeneous emulsion. The mixture is vacuum degassed for 40 minutes, and then the armored aluminum substrate is drawn and impregnated in the homogeneous emulsion, and dried by blast heating to obtain an F-BN@PANI conductive anti-corrosion coating on the surface of the armored aluminum material.

[0034] Among them, the addition amount of F-BN@PANI is 3.0~10.0wt%, the addition amount of epoxy resin and compound curing agent is 59~66wt%, the ratio between epoxy resin and curing compound agent is 2:1~1.5, the addition amount of organic solvent is 30wt%, the addition amount of defoaming agent is 0.5wt%; the addition amount of dispersant is 0.5wt%, and the sum of the mass percentages of the above F-BN@PANI, epoxy resin and compound curing agent, organic solvent, defoaming agent and dispersant is 100wt%.

[0035] The organic solvent is any one of DMAc, ethanol, and methanol; the curing compound is any one of T-31 and polyamide 650 mixed with one or more of polyetheramine D400, T403, and T-99 in a mass ratio of 1:0.18-0.4; the defoaming agent is any one of BYK-057, BYK-088, TEGO Airex 902W, or DAPRO DF 900; and the dispersant is any one of BYK-9076, EFKA4046, or Disperbyk-110.

[0036] Figure 1 Schematic diagram of the conductive anti-corrosion coating on armored aluminum material prepared in this invention. A conductive anti-corrosion coating 2 is applied to the surface of armored aluminum material 1. The polyaniline-coated F-BN composite filler 3 in this coating creates a dense network structure, enabling excellent lateral electron transport and improving overall conductivity. Polyaniline nanorods grow vertically on the F-BN surface, forming multiple barriers that effectively block the longitudinal penetration of ions from the corrosive medium. This multi-scale structure synergistically enhances the coating's conductivity and corrosion resistance, providing long-term protection for the armored aluminum material.

[0037] Example 1

[0038] First, boron oxide, urea and triethylamine trihydrofluoride were added to a solution consisting of 100 mL of deionized water and 100 mL of n-propanol in a molar ratio of 1:2:0.1, stirred and dissolved at 60°C, and naturally cooled and recrystallized after complete dissolution. The recrystallized precursor was dried and calcined in a tubular furnace at 900°C under a N2 atmosphere for 8 hours. The final product was ground evenly and sealed for storage to obtain fluorine-doped boron nitride nanosheets, labeled F-BNNS.

[0039] Then, 0.1 g of F-BN NS was dispersed in 300 mL of 60 wt% ethanol solution and dispersed at high speed for 30 min to obtain a stably dispersed mixed solution. 5 mL of hydrochloric acid solution was added to the mixed solution to keep the mixed solution acidic. Then, 1 mL of aniline and 1.2 g of benzoyl peroxide were added to the mixed solution in sequence. The mixture was polymerized in an ice bath (0 ° C) for 24 h to form polyaniline nanorods in situ on the F-BN surface. The mixture was then repeatedly rinsed with deionized water and ethanol and filtered until the pH was neutral. The mixture was dried at 60 ° C to obtain a polyaniline-coated F-BN composite filler, which was labeled as F-BN@PANI.

[0040] Finally, 3.0 wt% of the F-BN@PANI obtained in step 2 was added to 44.0 wt% of epoxy resin and stirred at 600 rpm for 40 minutes. Then, 22.0 wt% of a composite curing agent, 30 wt% of DMAc solvent, 0.5 wt% of BYK-057, and 0.5 wt% of BYK-9076 were added in sequence and stirred for 20 minutes to form a homogeneous emulsion, which was then vacuum-degassed for 40 minutes. The composite curing agent was a mixture of T-31 and polyetheramine D400 in a mass ratio of 1:0.3. The armored aluminum substrate was then dipped in the homogeneous emulsion and dried with air blast heating for 40 minutes to obtain the F-BN@PANI conductive anti-corrosion coating on the armored aluminum surface.

[0041] Example 2

[0042] First, boric acid, melamine, and potassium fluoride were added to a solution consisting of 100 mL of deionized water and 100 mL of ethanol in a molar ratio of 1:4:0.3, stirred and dissolved at 60°C, and naturally cooled and recrystallized after complete dissolution. The recrystallized precursor was dried and calcined in a tubular furnace at 1250°C under a N2 atmosphere for 5 hours. The final product was ground evenly and sealed for storage to obtain fluorine-doped boron nitride nanosheets, labeled F-BNNS.

[0043] Then, 0.3 g of F-BN NS was dispersed in 400 mL of 45 wt% ethanol solution and dispersed at high speed for 30 min to obtain a stably dispersed mixed solution. 8.5 mL of dodecylsulfonic acid solution was added to the mixed solution to keep the mixed solution acidic. Then, 2 mL of aniline and 2.8 g of ammonium persulfate were added to the mixed solution in sequence. The mixture was polymerized in an ice bath (0 ° C) for 20 h to form polyaniline nanorods in situ on the F-BN surface. The mixture was then repeatedly rinsed with deionized water and ethanol and filtered until the pH was neutral. The mixture was dried at 60 ° C to obtain a polyaniline-coated F-BN composite filler, which was labeled as F-BN@PANI.

[0044] Finally, 3 wt% of the F-BN@PANI obtained in step 2 was added to 37.7 wt% of epoxy resin and stirred at 600 rpm for 40 minutes. Then, 28.3 wt% of a composite curing agent, 30 wt% of ethanol, 0.5 wt% of BYK-088, and 0.5 wt% of EFKA 4046 were added sequentially and stirred for 20 minutes to form a homogeneous emulsion, which was then vacuum-degassed for 40 minutes. The composite curing agent was composed of a mixture of polyamide 650 and polyetheramine T403 in a mass ratio of 1:0.18. The armored aluminum substrate was then dipped in the homogeneous emulsion and dried with air blast heating for 30 minutes to obtain the F-BN@PANI conductive anti-corrosion coating on the armored aluminum surface.

[0045] Example 3

[0046] First, boric acid, melamine, and potassium fluoride were added to a solution consisting of 100 mL of deionized water and 100 mL of ethanol in a molar ratio of 1:4:0.3, stirred and dissolved at 60°C, and naturally cooled and recrystallized after complete dissolution. The recrystallized precursor was dried and calcined in a tubular furnace at 1250°C under a N2 atmosphere for 5 hours. The final product was ground evenly and sealed for storage to obtain fluorine-doped boron nitride nanosheets, labeled F-BNNS.

[0047] Then, 0.3 g of F-BN NS was dispersed in 500 mL of 60 wt% ethanol solution and subjected to high shear for 30 min to obtain a stably dispersed mixed solution. 8.5 mL of dodecylsulfonic acid solution was added to the mixed solution to keep the mixed solution acidic. Then, 2 mL of aniline and 2.8 g of ammonium persulfate were added to the mixed solution in sequence. The mixture was polymerized in an ice bath (0 ° C) for 20 h to in situ form polyaniline nanorods on the F-BN surface. The mixture was then repeatedly rinsed and filtered with deionized water and ethanol until the pH was neutral and dried at 60 ° C to obtain a polyaniline-coated F-BN composite filler, labeled as F-BN@PANI.

[0048] Finally, 7.5 wt% of the F-BN@PANI obtained in step 2 was added to 38.4 wt% of epoxy resin and stirred at 600 rpm for 40 minutes. Then, 23.1 wt% of a composite curing agent, 30 wt% of methanol, 0.5 wt% of TEGOAirex 902W, and 0.5 wt% of Disperbyk-110 were added and stirred for 20 minutes to form a homogeneous emulsion, which was then vacuum degassed for 40 minutes. The composite curing agent was a mixture of T-31 and D400 in a mass ratio of 1:0.35. The armored aluminum substrate was then dipped in the homogeneous emulsion and dried with air blast heating for 1 hour to obtain a conductive anti-corrosion coating of F-BN@PANI on the surface of the armored aluminum.

[0049] Example 4

[0050] First, boron oxide, guanidine hydrochloride and ammonium fluoride were added to 200 mL of ethanol solution in a molar ratio of 1:5.5:0.2, stirred and dissolved at 60°C, and naturally cooled and recrystallized after complete dissolution. The recrystallized precursor was dried and calcined in a tubular furnace at 1300°C under N2 atmosphere for 4 hours. The final product was ground evenly and sealed for storage to obtain fluorine-doped boron nitride nanosheets, labeled F-BN NS.

[0051] Then, 0.5 g of F-BN NS was dispersed in 400 mL of 40 wt% ethanol solution and dispersed at high speed for 30 min to obtain a stably dispersed mixed solution. 6.5 mL of dodecylbenzenesulfonic acid solution was added to the mixed solution to keep the mixed solution acidic. Then, 2.5 mL of aniline and 3.6 g of manganese dioxide were added to the mixed solution in sequence. The mixture was polymerized in an ice bath (0 ° C) for 21 h to form polyaniline nanorods in situ on the F-BN surface. The mixture was then repeatedly rinsed with deionized water and ethanol and filtered until the pH was neutral. The mixture was dried at 60 ° C to obtain a polyaniline-coated F-BN composite filler, which was labeled as F-BN@PANI.

[0052] Finally, 10 wt% of the F-BN@PANI obtained in step 2 was added to 33.7 wt% of epoxy resin and stirred at 600 rpm for 40 minutes. Then, 25.3 wt% of a composite curing agent, 30 wt% of methanol, 0.5 wt% of DAPRO DF 900, and 0.5 wt% of EFKA4046 were added in sequence and stirred for 20 minutes to form a homogeneous emulsion, which was then vacuum degassed for 40 minutes. The composite curing agent was composed of a mixture of polyamide 650 and D400 in a mass ratio of 1:0.4. The armored aluminum substrate was then dipped in the homogeneous emulsion and dried with air blast heating for 20 minutes to obtain a conductive anti-corrosion coating of F-BN@PANI on the surface of the armored aluminum.

[0053] Comparative Example 1

[0054] Boric acid, melamine and potassium fluoride were added to a solution consisting of 100 mL of deionized water and 100 mL of ethanol in a molar ratio of 1:4:0.3, stirred and dissolved at 60°C, and naturally cooled and recrystallized after complete dissolution. The recrystallized precursor was dried and calcined in a tubular furnace at 1250°C for 5 hours under a N2 atmosphere. The final product was ground evenly and sealed for storage to obtain fluorine-doped boron nitride nanosheets, labeled F-BNNS.

[0055] 7.5 wt% of the fluorine-doped boron nitride nanosheets obtained in step 1 were added to 41 wt% of epoxy resin and stirred at 600 rpm for 40 minutes. Then, 20.5 wt% of a composite curing agent, 30 wt% of methanol, 0.5 wt% of BYK-088, and 0.5 wt% of Disperbyk-110 were added and stirred for 20 minutes to form a homogeneous emulsion, which was then vacuum-degassed for 40 minutes. The composite curing agent was a mixture of polyamide 650 and T403 in a mass ratio of 1:0.35. The armored aluminum substrate was then dipped in the homogeneous emulsion and dried by forced air heating for 30 minutes to form a conductive F-BN anti-corrosion coating on the armored aluminum surface.

[0056] Comparative Example 2

[0057] 0g of F-BN NS was dispersed in 500mL of ethanol solution and dispersed under high-speed shear for 30 minutes to form a homogeneous solution. 8.5mL of dodecylsulfonic acid solution was added to the solution to maintain acidity. Then, 2mL of aniline and 2.8g of ammonium persulfate were added sequentially to the solution. Polymerization was carried out in an ice bath (0°C) for 20 hours. The solution was then rinsed and filtered repeatedly with deionized water and ethanol until the pH was neutral, and dried at 60°C to obtain a polyaniline nanorod composite filler, labeled as PANI NR.

[0058] Next, 5 wt% of the PANI NR obtained in the previous step was added to 40.6 wt% of epoxy resin and stirred at 600 rpm for 40 minutes. Then, 23.4 wt% of a composite curing agent, 30 wt% of methanol, 0.5 wt% of EGO Airex 902W, and 0.5 wt% of BYK-9076 were added and stirred for 20 minutes to form a homogeneous emulsion, which was then vacuum-degassed for 40 minutes. The composite curing agent was composed of a mixture of polyamide 650 and T403 in a mass ratio of 1:0.35. The armored aluminum substrate was then dipped in the homogeneous emulsion and dried with air blast heating for 40 minutes to form a PANI conductive anti-corrosion coating on the armored aluminum surface.

[0059] Comparative Example 3

[0060] 44.5wt% epoxy resin was stirred at 600rpm for 40 minutes. Then, 24.5wt% of a composite curing agent, 30wt% DMAc, 0.5wt% BYK-057, and 0.5wt% Disperbyk-110 were added. The mixture was stirred for 20 minutes to form a homogeneous emulsion, which was then vacuum-degassed for 40 minutes. The composite curing agent was a mixture of polyamides T-31 and T-99 in a mass ratio of 1:0.2. The armored aluminum substrate was then dipped in the homogeneous emulsion and dried with forced air heating for 20 minutes to form an anti-corrosion coating.

[0061] The coating was tested on a Coster CS-310H electrochemical workstation to verify its anti-corrosion performance. The Ag / AgCl electrode was used as the reference electrode, the platinum electrode was used as the auxiliary electrode, and the aluminum electrode coated with the coating was used as the working electrode (exposed area 1cm 2 ), the test medium is 3.5% NaCl solution, the conductive anti-corrosion coating armored aluminum materials prepared in Examples 1-4 and Comparative Examples 1-3 are corroded and immersed for 15 days, the test potential range is -0.25 to 0.25 V (relative to the open circuit potential), the scan rate is 1 mV / s, and the electrochemical parameter fitting results are shown in Table 1.

[0062] Table 1 Electrochemical parameter fitting results

[0063] <![CDATA[E o / V]]> <![CDATA[i o / A·cm -2 ]]> <![CDATA[v corr / mm·a -1 ]]> Example 1 -0.5319 <![CDATA[3.858×10 -7 ]]> <![CDATA[4.53×10 -3 ]]> Example 2 -0.4381 <![CDATA[1.518×10 -7 ]]> <![CDATA[1.78×10 -3 ]]> Example 3 -0.3499 <![CDATA[2.854×10 -8 ]]> <![CDATA[3.35×10 -4 ]]> Example 4 -0.3939 <![CDATA[2.027×10 -7 ]]> <![CDATA[2.38×10 -3 ]]> Comparative Example 1 -0.4135 <![CDATA[4.460×10 -6 ]]> <![CDATA[6.40×10 -3 ]]> Comparative Example 2 -0.4857 <![CDATA[3.171×10 -6 ]]> <![CDATA[3.72×10 -2 ]]> Comparative Example 3 -0.4697 <![CDATA[1.862×10 -6 ]]> <![CDATA[2.18×10 -3 ]]>

[0064] According to the data in Table 1, each embodiment is superior to the comparative example in terms of self-corrosion potential, self-corrosion current density and corrosion rate, showing a significant protective effect. The self-corrosion potential of the samples of the embodiment is positively shifted compared with the comparative example. Among them, the self-corrosion potential of Example 3 is -0.3499V, which is 136mV positively shifted compared with -0.4857V of Comparative Example 2, indicating that the coating prepared in Example 3 can effectively improve the electrochemical stability of the substrate. In terms of self-corrosion current density, i0 of Example 3 is only 2.854×10 -8 A.cm -2 , which is significantly lower than 4.460×10 -6 A.cm -2 , the reduction rate is more than two orders of magnitude. In terms of corrosion rate, the corrosion rate of Example 3 is 3.35×10 -4 mm·a -1 , only comparative example 1 (6.40×10 -3 mm·a -1 The overall results show that the conductive anti-corrosion coating can significantly improve the corrosion resistance of aluminum in an ionic environment.

[0065] The conductivity of the samples was measured at room temperature using a four-probe tester in accordance with GB / T 2439-2001, "Rubber, vulcanized or thermoplastic — Determination of electrical conductivity and dissipative properties." The sample size was (2 × 2 × 0.5) mm. The coating thickness was measured using a high-precision coating thickness gauge. Coating adhesion was measured according to GB9286-1988, "Paint and varnish film cross-cut test." The test results are shown in Table 2.

[0066] Table 2 Comparison of the performance of the conductive anti-corrosion coatings prepared in the examples and comparative examples

[0067]

[0068]

[0069] From Table 2, it can be seen that the coatings prepared in each embodiment are superior to the comparative example samples in terms of vertical conductivity, adhesion and coating thickness. The vertical conductivity of the coatings in the embodiment is significantly higher than that in the comparative example, both at 10 -4 S cm -1 The vertical conductivity of Example 3 reaches 6.27×10 -4 S cm -1 , compared with 3.14×10 -6 S cm -1This improvement is approximately 200 times, indicating that the coating has excellent electrical conductivity. In terms of adhesion, all samples in the examples achieved levels 0 to 2, demonstrating strong substrate bonding. Example 1 achieved level 0 adhesion, the best performance. In terms of coating thickness, the example coatings ranged from 142.1 to 156.3 μm, representing a micron-level coating.

[0070] The above-described embodiments merely represent specific implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A method for preparing a conductive anti-corrosion coating on the surface of a cable armored aluminum material, characterized in that: Please follow the steps below to implement: Step 1: Preparation of F-doped boron nitride nanosheets The boron source, nitrogen source and fluorine source are dissolved in a solvent in a molar ratio, heated and stirred to dissolve, and naturally cooled and recrystallized after complete dissolution. The precursor obtained by recrystallization is dried, calcined and ground to obtain F-doped boron nitride nanosheets, which are labeled as F-BN NS; Step 2: Preparation of polyaniline-coated F-BN composite filler by in-situ polymerization The F-BN NS obtained in step 1 is dispersed in an ethanol solution to obtain a mixed solution, an acidic solution is added to the mixed solution to keep the mixed solution acidic, and then aniline and a polymerization initiator are added to the mixed solution in sequence. The mixed solution is placed in an ice bath, and aniline is adsorbed and directionally polymerized to form polyaniline nanorods in situ on the surface of the F-BN NS. The polyaniline nanorods are then repeatedly rinsed with deionized water and ethanol, filtered until the pH is neutral, and dried at 60°C to obtain a polyaniline-coated F-BN composite filler, which is labeled as F-BN@PANI. Step 3, preparation of F-BN@PANI conductive anti-corrosion coating The F-BN@PANI obtained in step 2 is added to the epoxy resin and stirred, and then a curing compounding agent, an organic solvent, a defoaming agent, and a dispersant are added and stirred again to form a homogeneous emulsion. The mixture is vacuum degassed, and then the armored aluminum substrate is drawn and impregnated in the homogeneous emulsion, and dried by blast heating to obtain the F-BN@PANI conductive anti-corrosion coating on the surface of the armored aluminum material.

2. The method for preparing a conductive anti-corrosion coating on the surface of a cable armored aluminum material according to claim 1, characterized in that: The boron source described in step 1 is any one or more of boron oxide, borax and boric acid, the nitrogen source is any one or more of urea, guanidine hydrochloride and melamine, the fluorine source is any one of triethylamine trihydrofluoride, sodium fluoride, potassium fluoride and ammonium fluoride, and the molar ratio of the boron source, the nitrogen source and the fluorine source is 1:2~5.5:0.1~0.3; the solvent is composed of deionized water and n-propanol or anhydrous ethanol, the volume ratio of deionized water to alcohol is 0~1:1, and the solvent is 200 mL; the calcination temperature is 900~1300℃, and the calcination time is 4~8h.

3. The method for preparing a conductive anti-corrosion coating on the surface of a cable armored aluminum material according to claim 1, characterized in that: In step 2, the acidic solution is any one or more of hydrochloric acid, sulfuric acid, dodecylsulfonic acid and dodecylbenzenesulfonic acid, with a concentration of 1 mol / L; the polymerization initiator is any one or more of ammonium persulfate, benzoyl peroxide, ferric chloride and manganese dioxide; and the polymerization time is 18 to 24 hours.

4. The method for preparing a conductive anti-corrosion coating on the surface of a cable armored aluminum material according to claim 1, characterized in that: In step 2, the dispersed mass of F-BN NS is 0.1-0.5 g, the mass fraction of the ethanol solution is 30-60 wt%, the volume is 300-500 ml, the volume of the acidic solution added is 5-8.5 mL, the amount of aniline added is 1-2.5 mL, and the amount of the polymerization initiator added is 1.2-3.6 g.

5. The method for preparing a conductive anti-corrosion coating on the surface of a cable armored aluminum material according to claim 1, characterized in that: In step 3, the amount of F-BN@PANI added is 3.0-10.0 wt%; the amount of epoxy resin and compound curing agent added is 59-66 wt%, wherein the ratio between epoxy resin and curing compound is 2:1-1.5; the organic solvent is any one of DMAc, ethanol, and methanol, and the addition amount is 30 wt%; the curing compound is any one of T-31 and polyamide 650 and one or more of polyetheramine D400, T403, and T-99, mixed in a mass ratio of 1:0.18-0.4; the defoamer is BYK-057, BYK-088, TEGO Airex 902W, or DAPRO DF 900, with an addition amount of 0.5wt%; the dispersant is selected from any one of BYK-9076, EFKA4046 or Disperbyk-110, etc., with an addition amount of 0.5wt%, wherein the sum of the mass percentages of F-BN@PANI, epoxy resin and composite curing agent, organic solvent, defoaming agent and dispersant is 100wt%.

6. A conductive anti-corrosion coating prepared according to the method for preparing a conductive anti-corrosion coating on the surface of a cable armored aluminum material according to any one of claims 1 to 5.

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