Epoxy resin-based hydrogen-resistant coating, preparation method and application thereof, hydrogen-resistant coating and preparation method thereof

Abstract

The invention relates to the technical field of hydrogen-resistant materials, and discloses an epoxy resin-based hydrogen-resistant coating and a preparation method and application thereof, and a hydrogen-resistant coating and a preparation method thereof. The method comprises the following steps: (1) carrying out mixed reaction I on a mixed solution containing carboxymethyl chitosan and a dispersion solution containing graphene oxide to obtain modified graphene oxide; (2) mixing the modified graphene oxide, waterborne epoxy resin and a curing agent for reaction I I to obtain the epoxy resin-based hydrogen-resistant coating. By adopting the method for preparing the epoxy resin-based hydrogen-resistant coating provided by the invention, the prepared epoxy resin-based hydrogen-resistant coating is applied to a hydrogen-resistant coating, has good adhesiveness with a substrate and is not easy to fall off, and the surface of the hydrogen-resistant coating is smooth and has excellent corrosion resistance and hydrogen barrier property; the effect is obviously better than that of pure steel plates and raw material water-borne epoxy resin.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen barrier materials, and in particular to an epoxy resin-based hydrogen barrier coating and a preparation method and application thereof, a hydrogen barrier coating and a preparation method thereof. Background Art

[0002] Hydrogen transportation is a crucial component of the industrialization of hydrogen energy. Hydrogen damage is a significant challenge currently facing hydrogen infrastructure development. One of the most critical and challenging issues in hydrogen-blended natural gas pipeline transportation is ensuring high compatibility between the pipeline material and hydrogen. Hydrogen damage can lead to reduced ductility, fracture resistance, and fatigue performance, causing material degradation and shortening service life, even leading to hazardous accidents. This severely restricts the future application and development of the hydrogen energy industry.

[0003] To address the issue of hydrogen damage, hydrogen barrier coating technology has emerged. Hydrogen barrier coatings can slow or prevent hydrogen penetration without damaging the material's mechanical properties, thus preventing hydrogen damage to metal materials at the source. Currently, common hydrogen barrier coatings, such as metal and metal oxide hydrogen barrier coatings and carbon / nitride hydrogen barrier coatings, each have limitations due to differences in material composition and structure. These limitations include, but are not limited to, easy coating shedding, high costs, and complex preparation processes. Therefore, continuous exploration of new materials and processes is necessary to overcome these limitations.

[0004] Therefore, it is necessary to develop a coating suitable for hydrogen transport pipelines that is both resistant to hydrogen permeation and corrosion-resistant, and suitable for hydrogen-rich environments. This is crucial to ensuring the safety and service life of hydrogen transport pipelines and meeting industrial needs. Epoxy resin coatings have excellent chemical stability, corrosion resistance, wear resistance, and good adhesion. They are not only simple to prepare but also meet environmental requirements, making them widely used in the pipeline field. The cured network formed within epoxy resin increases the complexity of the internal channels, enabling them to partially block the movement of hydrogen. Under certain conditions, they generally exhibit good hydrogen barrier properties. Therefore, epoxy resin has broad application prospects as a hydrogen barrier coating in hydrogen pipelines.

[0005] For example, CN117050611A discloses a method for preparing a novel anti-corrosion and high-temperature resistant coating. This method uses a water-based epoxy resin as the base component of the coating, an aqueous graphene oxide solution as a reinforcing agent and a conductive agent, a modified chitosan emulsion as a flexibilizer and an antibacterial agent, and a modified nano-silica emulsion as a filler and a brightener. This technical solution solves the problem of dispersing nanoparticles in the water-based epoxy resin and improves the high-temperature stability of the water-based epoxy resin. However, this method still suffers from poor compactness and the inability to achieve long-term service. Summary of the Invention

[0006] The purpose of the present invention is to solve the problems of poor density and poor long-term service effect of the hydrogen barrier coating in the prior art.

[0007] In order to achieve the above object, the first aspect of the present invention provides a method for preparing an epoxy resin-based hydrogen barrier coating, the method comprising:

[0008] (1) performing a mixing reaction I on a mixed solution containing carboxymethyl chitosan and a dispersion containing graphene oxide to obtain modified graphene oxide;

[0009] (2) mixing the modified graphene oxide, water-based epoxy resin, and curing agent to react ⅠⅠ to obtain the epoxy resin-based hydrogen barrier coating;

[0010] Wherein, in step (1), the mass ratio of the carboxymethyl chitosan to the graphene oxide is 1-2:1;

[0011] In step (2), the mass ratio of the modified graphene oxide to the waterborne epoxy resin is 1:200-2000.

[0012] The second aspect of the present invention provides an epoxy resin-based hydrogen barrier coating prepared by the method described in the first aspect.

[0013] The third aspect of the present invention provides use of the epoxy resin-based hydrogen barrier coating described in the second aspect in a hydrogen barrier coating.

[0014] A fourth aspect of the present invention provides a hydrogen barrier coating, comprising a substrate and an epoxy resin-based hydrogen barrier coating coated on a surface of the substrate;

[0015] The epoxy resin-based hydrogen barrier coating is the epoxy resin-based hydrogen barrier coating described in the second aspect.

[0016] The fifth aspect of the present invention provides a method for preparing the hydrogen barrier coating described in the fourth aspect, the method comprising: coating an epoxy resin-based hydrogen barrier coating on a substrate, and curing the substrate to obtain the hydrogen barrier coating.

[0017] Through the above technical solution, the present invention has at least the following advantages:

[0018] (1) The method for preparing epoxy resin-based hydrogen barrier coating provided by the present invention has a simple preparation process and a wide range of raw material sources, and has broad application prospects.

[0019] (2) The epoxy resin-based hydrogen barrier coating provided by the present invention exhibits good hydrogen ion corrosion and barrier properties when applied to hydrogen barrier coatings. The epoxy resin-based hydrogen barrier coating can form a uniformly distributed barrier structure, which can, on the one hand, extend the hydrogen permeation path, and on the other hand, allow a portion of the hydrogen atoms that penetrate into the coating to be chemically absorbed by the CH sp3 bonds in the coating structure, thereby preventing hydrogen from entering the substrate.

[0020] (3) In the hydrogen barrier coating provided by the present invention, the epoxy resin-based hydrogen barrier coating has good adhesion to the substrate and is not easy to fall off. In addition, the surface of the hydrogen barrier coating is smooth and has excellent corrosion resistance and hydrogen barrier properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a flow chart of the method for preparing the hydrogen barrier coating provided by the present invention;

[0022] Figure 2 1 is an infrared spectrum of the modified graphene oxide and the raw graphene oxide according to Example 1 of the present invention;

[0023] Figure 3 1 is a Raman spectrum of the modified graphene oxide and the raw graphene oxide according to Example 1 of the present invention;

[0024] Figure 4 This is a microscopic SEM image of the hydrogen barrier coating prepared from the epoxy resin-based hydrogen barrier coating of Example 1 of the present invention and the raw material water-based epoxy resin coating;

[0025] Figure 5 1 is a Nyquist plot of the epoxy resin-based hydrogen barrier coating of Example 1 of the present invention and the raw waterborne epoxy resin after being immersed in a 3.5 wt % NaCl solution for different times;

[0026] Figure 6 Graphs of hydrogen permeation current density of a hydrogen barrier coating made from the epoxy resin-based hydrogen barrier coating of Example 1 of the present invention, pure X80 steel, and a raw material water-based epoxy resin coating;

[0027] Figure 7 This is a graph showing the hydrogen content of the hydrogen barrier coating made from the epoxy resin-based hydrogen barrier coating of Example 1 of the present invention, pure X80 steel, and raw material water-based epoxy resin coating. DETAILED DESCRIPTION

[0028] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0029] In the present invention, the normal temperature refers to a temperature of 23±2°C.

[0030] As mentioned above, the first aspect of the present invention provides a method for preparing an epoxy resin-based hydrogen barrier coating, the method comprising:

[0031] (1) performing a mixing reaction I on a mixed solution containing carboxymethyl chitosan and a dispersion containing graphene oxide to obtain modified graphene oxide;

[0032] (2) mixing the modified graphene oxide, water-based epoxy resin, and curing agent to react ⅠⅠ to obtain the epoxy resin-based hydrogen barrier coating;

[0033] Wherein, in step (1), the mass ratio of the carboxymethyl chitosan to the graphene oxide is 1-2:1;

[0034] In step (2), the mass ratio of the modified graphene oxide to the waterborne epoxy resin is 1:200-2000.

[0035] The inventors of the present invention discovered that the dispersibility and compatibility of graphene oxide (GO) with specific parameters in epoxy resin-based hydrogen barrier coatings directly affect their performance and applications. By utilizing the hydrogen bonds formed by specific groups of specific graphene oxide (GO) and carboxymethyl chitosan (CMCS) and the electrostatic attraction between molecules, it is possible to adsorb CMCS on GO. The resulting modified graphene oxide has a layered structure. When mixed with a water-based epoxy resin and a curing agent, not only is its dispersion stability significantly increased, but the cross-linking density of the polymer chains is also enhanced, thereby further enhancing the compatibility and stability of the water-based epoxy resin. The resulting epoxy resin-based hydrogen barrier coating exhibits excellent hydrogen ion corrosion and barrier properties.

[0036] Preferably, in step (1), the average sheet diameter of the graphene oxide is 0.2-8 μm, and the specific surface area is 2-15 cm 2 / g, and an average thickness of 0.3-2nm. In this preferred embodiment, the technical solution of the present invention can obtain a hydrogen barrier coating with better corrosion resistance and hydrogen barrier properties.

[0037] Preferably, in step (1), the solvent in the mixed liquid and the dispersion liquid is water.

[0038] Preferably, in step (1), the mixed solution is obtained by dissolving carboxymethyl chitosan and water and performing ultrasonic treatment I; the conditions of the ultrasonic treatment I include: power of 100-500W, time of 5-10min.

[0039] Preferably, in step (1), the dispersion is obtained by dissolving graphene oxide and water and ultrasonically treating ⅠI; the conditions of the ultrasonic treatment ⅠI include: power of 100-500W, time of 30-60min.

[0040] In step (1), the present invention has no particular restriction on the order of adding the mixed solution and the dispersion solution in the mixing reaction process. However, in order to better disperse the graphene oxide in the mixed solution, the present invention preferably adds the dispersion solution containing graphene oxide to the mixed solution containing carboxymethyl chitosan to carry out mixing reaction I to obtain modified graphene oxide.

[0041] Preferably, in step (2), the mass ratio of the modified graphene oxide to the waterborne epoxy resin is 1:400-2000. In this preferred embodiment, the technical solution of the present invention can obtain a hydrogen barrier coating with better corrosion resistance and hydrogen barrier properties.

[0042] Preferably, in step (2), the mass ratio of the waterborne epoxy resin to the curing agent is 2-5:1.

[0043] Preferably, the curing agent is Budford GF-G1 and / or CA8113.

[0044] Preferably, in step (1), the mixing reaction I is carried out at room temperature.

[0045] Preferably, in step (1), the conditions of the mixing reaction I include: a rotation speed of 200-400 rpm and a time of 5-30 min.

[0046] Preferably, the method further comprises: in step (1), subjecting the product of the mixed reaction I to ultrasonic treatment III to obtain the modified graphene oxide; the conditions of the ultrasonic treatment III include: power of 100-500W, time of 30-60min.

[0047] The method for preparing the epoxy resin-based hydrogen barrier coating of the present invention may further include post-processing methods known in the art, such as filtration and drying. For example, the product obtained from the mixing reaction I is filtered, rinsed with distilled water, and then freeze-dried to obtain the epoxy resin-based hydrogen barrier coating. This invention will not be described in detail herein, and persons skilled in the art should not be construed as limiting the present invention.

[0048] Preferably, in step (2), the modified graphene oxide is provided in the form of a modified graphene oxide dispersion.

[0049] More preferably, the modified graphene oxide dispersion is obtained by contacting the modified graphene oxide with water and performing ultrasonic treatment IV; the conditions of the ultrasonic treatment IV include: power of 100-500W, time of 20-40min.

[0050] Preferably, in step (2), the mixing reaction Ⅰ is carried out at room temperature.

[0051] Preferably, in step (2), the conditions of the mixing reaction Ⅱ include: a rotation speed of 200-400 rpm and a time of 2-7 min.

[0052] As mentioned above, the second aspect of the present invention provides an epoxy resin-based hydrogen barrier coating prepared by the method described in the first aspect.

[0053] As mentioned above, the third aspect of the present invention provides the use of the epoxy resin-based hydrogen barrier coating described in the second aspect in a hydrogen barrier coating.

[0054] As mentioned above, the fourth aspect of the present invention provides a hydrogen barrier coating, which includes a substrate and an epoxy resin-based hydrogen barrier coating coated on the surface of the substrate;

[0055] The epoxy resin-based hydrogen barrier coating is the epoxy resin-based hydrogen barrier coating described in the second aspect.

[0056] As mentioned above, the fifth aspect of the present invention provides a method for preparing the hydrogen barrier coating described in the fourth aspect, the method comprising: coating an epoxy resin-based hydrogen barrier coating on a substrate and performing a curing treatment to obtain the hydrogen barrier coating.

[0057] Preferably, the coating has a thickness of 100-120 μm.

[0058] Preferably, the coating tool is selected from at least one of a four-sided film coater, a wire rod coater, a frame coater and a spin coater.

[0059] Preferably, the curing treatment conditions include: a temperature of 40-80° C., preferably 50-80° C.; and a curing time of 12-36 hours, preferably 12-24 hours.

[0060] Preferably, the present invention Figure 1 A flow chart of the preparation method of the hydrogen barrier coating is provided, specifically:

[0061] (1) CMCS was placed in deionized water and ultrasonically dispersed in an ultrasonic device to form a mixed solution containing CMCS;

[0062] GO is dispersed in deionized water and ultrasonically dispersed in an ultrasonic device to form a dispersion containing GO;

[0063] The GO dispersion and the CMCS mixture were mixed and stirred to form a stable CMCS-GO solution. The modified graphene oxide was then obtained by filtration, washing, and freeze-drying.

[0064] (2) taking the modified graphene oxide obtained in step (1) and adding it to deionized water. Ultrasonicating the modified graphene oxide in an ultrasonic device to obtain an aqueous solution of the modified graphene oxide;

[0065] adding a water-based epoxy resin and a curing agent to the prepared modified graphene oxide aqueous solution, and stirring the mixture to obtain an epoxy resin-based hydrogen barrier coating;

[0066] (3) Take the prepared epoxy resin-based hydrogen barrier coating, place it flat on the pretreated steel plate, and evenly apply the epoxy resin-based hydrogen barrier coating to obtain a hydrogen barrier coating.

[0067] In the following examples, unless otherwise specified, the instruments, reagents, materials, etc. involved are conventional instruments, reagents, materials, etc., which can be obtained through conventional commercial channels. In addition, unless otherwise specified, the reagents used are commercially available analytical grade products.

[0068] Graphene oxide (GO-1): purchased from Shenzhen Hongdachang Evolution Technology Co., Ltd., with a sheet diameter of 0.5-5 μm and a specific surface area of ​​5-10 cm 2 / g, thickness is 0.335-1nm.

[0069] Graphene oxide (GO-2): purchased from Suzhou Tanfeng Technology Co., Ltd., with a sheet diameter of 10-50 μm and a specific surface area of ​​5-8 cm 2 , with a thickness of 1nm.

[0070] Example 1

[0071] (1) 0.4 g of CMCS was slowly added to 100 mL of deionized water and ultrasonically dispersed in a 400 W ultrasonic device for 10 min until a uniform mixture containing CMCS was formed;

[0072] GO was dispersed in 100 mL of deionized water and ultrasonically dispersed in a 400 W ultrasonic device for 60 min to ensure that GO was evenly dispersed in the deionized water to form a stable dispersion containing GO;

[0073] At room temperature, the GO dispersion was gradually added to the CMCS mixture, stirring at 200 rpm for 30 minutes to ensure thorough mixing of the two solutions and form a stable CMCS-GO solution. The modified graphene oxide was then obtained through filtration, multiple water washings, and freeze-drying.

[0074] (2) Take the modified graphene oxide prepared in step (1) and add it to 20 mL of deionized water. Ultrasonicate for 30 minutes in a 400 W ultrasonic device to obtain a uniformly dispersed modified graphene oxide aqueous solution;

[0075] At room temperature, water-based epoxy resin (4 g) and curing agent (CA8113, 1 g) were added to the prepared modified graphene oxide aqueous solution, and stirred at a stirring speed of 200 rpm for 5 minutes until a uniform epoxy resin-based hydrogen barrier coating was obtained.

[0076] The materials, their proportions, and reaction conditions of this embodiment are shown in Table 1.

[0077] Example 2 and Example 3 were prepared using the same method as Example 1, except that the materials, their ratios, and reaction conditions were different, as shown in Table 1.

[0078] Table 1

[0079]

[0080] Example 4

[0081] A method similar to that of Example 1 was used, except that GO-2 of equal mass was used to replace GO-1, to obtain an epoxy resin-based hydrogen barrier coating.

[0082] Example 5

[0083] A method similar to that of Example 1 was adopted, except that the amount of the waterborne epoxy resin in this example was kept unchanged, and the mass ratio of the modified graphene oxide to the waterborne epoxy resin was adjusted to 1:200 to obtain an epoxy resin-based hydrogen barrier coating.

[0084] Comparative Example 1

[0085] A method similar to that of Example 1 was adopted, except that the amount of carboxymethyl chitosan in this comparative example was kept unchanged, and the mass ratio of carboxymethyl chitosan to graphene oxide was adjusted to 0.5:1 to obtain an epoxy resin-based hydrogen barrier coating.

[0086] Comparative Example 2

[0087] A method similar to Example 1 was adopted, except that the amount of waterborne epoxy resin in this comparative example was kept unchanged, and the mass ratio of modified graphene oxide and waterborne epoxy resin was adjusted to 1:100 to obtain an epoxy resin-based hydrogen barrier coating.

[0088] Application Examples

[0089] Take an appropriate amount of the epoxy resin-based hydrogen barrier coating prepared in the example, place it evenly and flatly on the pretreated steel plate, and use a 40μm wire rod coater to evenly apply the epoxy resin-based hydrogen barrier coating to ensure that the coating thickness is consistently 120μm; then place the coated steel plate in an oven and cure it at a constant temperature of 70°C for 24h to ensure that the epoxy resin-based hydrogen barrier coating is completely cured on the surface of the steel plate to obtain a hydrogen barrier coating.

[0090] The cured hydrogen barrier coating was taken out and the coating thickness and coating quality (including corrosion resistance and hydrogen barrier performance) were accurately measured using a thickness gauge. The test results are shown in the table below.

[0091] The test methods involved are as follows:

[0092] Corrosion Resistance: The hydrogen barrier coating was immersed in a 3.5wt% NaCl solution and subjected to electrochemical impedance spectroscopy (EIS) testing using a CHI660E electrochemical workstation produced by Shanghai Zhenhua Instrument Co., Ltd. The coating sample served as the working electrode, a saturated calomel electrode served as the reference electrode, and a platinum sheet served as the counter electrode. The EIS test frequency range was set from 100kHz to 10mHz, with a perturbation voltage of 20mV / s. The corrosion resistance of the coating under immersion conditions was analyzed based on the modulus values.

[0093] Hydrogen barrier performance: The hydrogen permeation current density and hydrogen content of the hydrogen barrier coating were tested. The electrochemical hydrogen permeation test was performed using a Devanathan-Stachurski double electrolytic cell device. The specific operation was as follows: the sample to be tested was fixed between the hydrogen charging end and the hydrogen permeation end, using a three-electrode system; the hydrogen charging solution was 3g / L thiourea + 0.2mol / L NaOH solution, and the hydrogen permeation solution was 0.2mol / L NaOH solution; the steel surface of the hydrogen permeation end was pre-polished with 1500# sandpaper. At a current density of 20mA / cm 2 Nickel plating was performed for 4 minutes under 40°C conditions to prevent the iron specimen from self-dissolution or passivation in a strong alkaline solution, which could affect the accurate measurement of the anodic current. This process also catalyzes the atomic hydrogen discharge reaction, thereby improving the measurement sensitivity. Finally, Squidstat User Interface software was used to measure and record the ip (permeation current density)-t (permeation time) curve. After hydrogen charging, the diffusible hydrogen and dissolved hydrogen contents were measured using a BRUKER G4 PHOENIX DH hydrogen meter. The instrument's sample tube had a diameter of 30 mm, and the system used a 10-point gas calibration. The diffusible hydrogen content was measured by heating to 300°C, while the dissolved hydrogen content was measured by heating to 900°C.

[0094] Table 2

[0095]

[0096] The present invention is exemplified in Figure 2 Provided are infrared spectra of the modified graphene oxide and raw graphene oxide of Example 1 of the present invention. Figure 2 It can be found that the graphene oxide powder sample has a peak at about 1603 cm -1 Nearby carboxyl groups (-C=O) and at 3200 cm -1 The obvious asymmetric stretching vibration of hydroxyl (-OH) near the surface of graphene oxide indicates that the surface of graphene oxide is rich in hydroxyl and carboxyl groups. The attraction between these groups and the environment in aqueous solution makes graphene oxide more likely to aggregate and accumulate. The characteristic peaks of epoxy resin-based hydrogen barrier coatings can be seen at 3000cm -1 -3500cm -1 A broad peak appears, representing the overlapping characteristic absorption peaks of OH and NH. This peak is broadened due to hydrogen bonding between the OH and NH groups, resulting in the overlap of the two vibrational peaks. This indicates that specific groups of carboxymethyl chitosan form hydrogen bonds with hydroxyl groups on the graphene oxide surface, enabling adsorption of carboxymethyl chitosan onto the graphene oxide. This demonstrates that the preparation method of the epoxy resin-based hydrogen barrier coating provided by the present invention successfully modifies graphene oxide.

[0097] The present invention is exemplified in Figure 3 The Raman spectra of the modified graphene oxide and the raw graphene oxide of Example 1 of the present invention are provided. Figure 3 It can be found that 1350cm -1 D band at 1590cm -1 The G band is clearly present at the lattice depth. The D band is typically attributed to edge or lattice defects, and its intensity is related to the defect density in the sample. The G band intensity, on the other hand, is generally related to the structural quality of the material. The calculated ID / IG ratio (the ratio of the D-band to the G-band intensities) for graphene oxide is 0.87, while that for epoxy-based hydrogen barrier coatings is 0.73. A decrease in the ID / IG value generally indicates improved crystallinity or a reduction in the number of defects in graphene-based materials, further confirming the successful modification of graphene oxide with carboxymethyl chitosan.

[0098] The present invention is exemplified in Figure 4 Provided are microscopic SEM images of a hydrogen barrier coating made from an epoxy resin-based hydrogen barrier coating according to Example 1 of the present invention and a raw water-based epoxy resin coating; wherein the raw water-based epoxy resin coating is formed by coating the raw water-based epoxy resin on pure X80 steel; (a) refers to a microscopic SEM image of the raw water-based epoxy resin coating, and (b) refers to a microscopic SEM image of the hydrogen barrier coating. Figure 4It can be seen that the interface of the raw water-based epoxy resin coating is relatively smooth, while an obvious flaky layered distribution phenomenon is observed at the interface of the epoxy resin-based hydrogen barrier coating. The presence of carboxymethyl functional groups provides more adsorption sites on the surface of graphene oxide. The interaction between the functional groups enhances the cross-linking density of the polymer chain, and the compatibility between the two components is enhanced.

[0099] The present invention is exemplified in Figure 5 Provided are the Nyquist plots of a hydrogen barrier coating made from an epoxy resin-based hydrogen barrier coating according to Example 1 of the present invention and a raw water-based epoxy resin coating after being immersed in a 3.5wt% NaCl solution for different times; wherein the raw water-based epoxy resin coating is formed by coating the raw water-based epoxy resin on pure X80 steel; a larger impedance arc indicates that the coating has a higher real impedance value (i.e., the value corresponding to the horizontal axis), indicating better corrosion resistance. Figure 5 It can be seen that the actual impedance value of the raw water-based epoxy resin coating at the beginning of immersion (0h) is 8.4×10 7 Ω·cm 2 Observing the Nyquist plot of the hydrogen barrier coating made of epoxy resin-based hydrogen barrier coating, it can be found that the real impedance value of 0h is 1.1×10 8 Ω·cm 2 , which is one order of magnitude higher than the raw water-based epoxy resin. This shows that the modified graphene oxide is uniformly dispersed in the raw water-based epoxy resin and can greatly improve the corrosion resistance of the hydrogen barrier coating.

[0100] The present invention is exemplified in Figure 6 The hydrogen permeation current density diagram of the hydrogen barrier coating prepared by the epoxy resin-based hydrogen barrier coating of Example 1 of the present invention and pure X80 steel and raw material water-based epoxy resin coating is provided, as well as Figure 7 Provided are hydrogen content graphs for a hydrogen barrier coating made from the epoxy resin-based hydrogen barrier coating of Example 1 of the present invention, pure X80 steel, and a raw water-based epoxy resin coating; wherein the raw water-based epoxy resin coating is formed by coating pure X80 steel with a raw water-based epoxy resin; the left graph is a hydrogen permeation current density graph, and the right graph is a hydrogen content graph; a smaller hydrogen permeation current density indicates better hydrogen barrier properties of the coating, indicating a slower hydrogen permeation rate within the coating, and effectively suppressing hydrogen permeation.

[0101] Depend on Figure 6 and Figure 7As can be seen, pure X80 steel exhibited the highest hydrogen permeation current density, at 9.2 μA. In comparison, the sample coated with the raw water-based epoxy resin exhibited a permeation current density of only 3.6 μA, while the hydrogen barrier coating exhibited the lowest permeation current density, at 0.6 μA, representing a 93.49% reduction compared to pure X80 steel. Regarding dissolved hydrogen content, the pure X80 steel sample had a dissolved hydrogen content of 3.7 ppm, while the sample coated with the raw water-based epoxy resin had a dissolved hydrogen content of approximately 2.5 ppm. The hydrogen barrier coating exhibited the lowest hydrogen content, at 0.4 ppm. Lower hydrogen content indicates less hydrogen permeating into the substrate and concentrating in specific traps within the material, resulting in a stronger hydrogen barrier. The uniform dispersion of modified graphene oxide within the epoxy resin maximizes the hydrogen diffusion path, reducing hydrogen permeability, demonstrating that the modified graphene oxide effectively enhances the hydrogen barrier properties of the hydrogen barrier coating.

[0102] The above results show that the epoxy resin-based hydrogen barrier coating prepared by the method of the present invention is applied to the hydrogen barrier coating, and exhibits good corrosion resistance and hydrogen barrier properties, which are significantly better than those of pure steel plates and raw water-based epoxy resin.

[0103] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A method for preparing an epoxy resin-based hydrogen barrier coating, characterized in that: The method includes: (1) performing a mixing reaction I on a mixed solution containing carboxymethyl chitosan and a dispersion containing graphene oxide to obtain modified graphene oxide; (2) mixing the modified graphene oxide, water-based epoxy resin, and curing agent to react ⅠⅠ to obtain the epoxy resin-based hydrogen barrier coating; Wherein, in step (1), the mass ratio of the carboxymethyl chitosan to the graphene oxide is 1-2:1; In step (2), the mass ratio of the modified graphene oxide to the waterborne epoxy resin is 1:200-2000.

2. The method according to claim 1, wherein In step (1), the average sheet diameter of the graphene oxide is 0.2-8 μm and the specific surface area is 2-15 cm 2 / g, with an average thickness of 0.3-2nm.

3. The method according to claim 1, wherein In step (2), the mass ratio of the modified graphene oxide to the waterborne epoxy resin is 1:400-2000; And / or, the mass ratio of the waterborne epoxy resin to the curing agent is 2-5:1; And / or, the curing agent is Budford GF-G1 and / or CA8113.

4. The method according to any one of claims 1 to 3, wherein: In step (1), the conditions of the mixing reaction I include: a rotation speed of 200-400 rpm and a time of 5-30 min.

5. The method according to any one of claims 1 to 3, wherein: In step (2), the conditions of the mixing reaction Ⅱ include: a rotation speed of 200-400 rpm and a time of 2-7 min.

6. An epoxy resin-based hydrogen barrier coating prepared by the method according to any one of claims 1 to 5.

7. Use of the epoxy resin-based hydrogen barrier coating according to claim 6 in hydrogen barrier coatings.

8. A hydrogen barrier coating, characterized in that: The hydrogen barrier coating comprises a substrate and an epoxy resin-based hydrogen barrier coating coated on the surface of the substrate; The epoxy resin-based hydrogen barrier coating is the epoxy resin-based hydrogen barrier coating according to claim 6.

9. A method for preparing the hydrogen barrier coating according to claim 8, characterized in that: The method comprises: coating an epoxy resin-based hydrogen barrier coating on a substrate, and performing a curing treatment to obtain the hydrogen barrier coating.

10. The method according to claim 9, wherein: The coating has a thickness of 100-120 μm; And / or, the curing treatment conditions include: temperature of 40-80° C. and time of 12-36 hours.

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