Epoxy anticorrosive paint and preparation method thereof

Abstract

The invention discloses an epoxy anticorrosive coating and a preparation method thereof in the technical field of epoxy coatings. The epoxy anticorrosive coating comprises the following components in parts by weight: 110-130 parts of modified epoxy resin, 19-22 parts of a diluent, 0.9-1.2 parts of a composite nano filler, 10-12 parts of an auxiliary agent and 8-10 parts of a curing agent. The epoxy resin is subjected to blending modification through the modified resveratrol, so that the thermal stability of a matrix material is enhanced; meanwhile, the mica iron oxide filler is subjected to organic modification treatment, the dispersion effect of the filler in a resin system is optimized, epoxy group ring opening is initiated through imidazole, efficient combination of a resin matrix and the functional filler is achieved, the heat resistance limit of the epoxy coating is improved, meanwhile, the mechanical property and corrosion resistance of the coating are improved, and the service life of the coating is prolonged. The anticorrosive paint with excellent comprehensive performance is obtained.

Description

Technical Field

[0001] The present invention belongs to the technical field of epoxy coatings, and specifically refers to an epoxy anti-corrosion coating and a preparation method thereof. Background Art

[0002] Epoxy anti-corrosion coatings are high-performance protective coatings made mainly from epoxy resins, combined with curing agents and other auxiliary additives. The core lies in the chemical reaction between the epoxy resin and the curing agent to form a three-dimensional cross-linked network, endowing the coating film with excellent physical and chemical properties. As the base material, epoxy resin has a relatively high molecular weight and multiple active oxygen ring groups, which can undergo cross-linking reactions under the action of the curing agent to generate a coating film with chemical corrosion resistance, wear resistance, aging resistance, and high strength. Commonly used curing agents include amines, anhydrides, and polyamides, etc. These curing agents build the structural foundation of the coating film by undergoing ring-opening reactions with epoxy resins. The main characteristics of epoxy anti-corrosion coatings are their excellent adhesion, chemical resistance, and durability, which can effectively protect the base material from corrosion in harsh environments. Their application scope is extensive, covering fields such as petrochemical, ocean engineering, water treatment, and construction. For example, in the marine environment, epoxy anti-corrosion coatings can be used to prevent the corrosion of ship hulls and marine equipment. In industrial equipment, epoxy coatings can resist the erosion of acids, alkalis, and organic solvents. With the increasing environmental protection requirements, the non-toxic, low volatility, and environmental protection properties of epoxy anti-corrosion coatings have also become an important development trend. By continuously optimizing the ratio of epoxy resin to curing agent, improving the leveling and adhesion of the coating film, and developing new functional additives, the position of epoxy anti-corrosion coatings in the field of anti-corrosion technology will become more important.

[0003] Currently, the existing technologies mainly have the following problems: the poor thermal stability, mechanical properties, and corrosion resistance of epoxy coatings. Summary of the Invention

[0004] In view of the above situation, to overcome the defects of the existing technologies, the present invention provides an epoxy anti-corrosion coating and a preparation method thereof. To solve the problem of poor thermal stability of epoxy coatings, the present invention proposes to carry out blending modification of epoxy resin with modified resveratrol to enhance the thermal stability of the matrix material. At the same time, the mica iron oxide filler is subjected to organic modification treatment to optimize the dispersion effect of the filler in the resin system, and the epoxy ring is opened by imidazole to achieve the efficient combination of the resin matrix and the functional filler, while improving the heat resistance limit of the epoxy coating, enhancing the mechanical properties and corrosion resistance of the coating, and obtaining an anti-corrosion coating with excellent comprehensive performance.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows: The present invention provides an epoxy anti-corrosion coating, and the epoxy anti-corrosion coating comprises the following components in parts by weight: 110-130 parts of modified epoxy resin, 19-22 parts of diluent, 0.9-1.2 parts of composite nano filler, 10-12 parts of additive, and 8-10 parts of curing agent.

[0006] Preferably, the diluent comprises one of dodecyl glycidyl ether, epoxypropane benzyl ether, and ethylene glycol glycidyl ether.

[0007] Preferably, the additive is obtained by uniformly mixing defoaming agent BYK-A530 and toughening agent D-1217 in a mass ratio of 1:80-100.

[0008] Further, the additive is obtained by uniformly mixing defoaming agent BYK-A530 and toughening agent D-1217 in a mass ratio of 1:90.

[0009] Preferably, the curing agent comprises one of polyamide 651, polyamide 650, and polyamide 400.

[0010] Preferably, the modified epoxy resin is prepared from the following components in parts by weight: 16-18 parts of resveratrol, 1.2-1.4 parts of benzyltriethylammonium chloride, 210-220 parts of epichlorohydrin, 28-30 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and 86-92 parts of epoxy resin E51.

[0011] Preferably, the preparation method of the modified epoxy resin specifically comprises the following steps:

[0012] (1) Add resveratrol to a reactor, then add benzyltriethylammonium chloride and epichlorohydrin, mix evenly, and under nitrogen protection, heat and stir to react to obtain a mixed solution;

[0013] (2) Drop 40wt% sodium hydroxide solution into the mixed solution obtained in step (1), continue to react for 1 h, filter, separate liquid, take the organic layer, and dry to obtain epoxidized resveratrol. Add the epoxidized resveratrol to 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, heat and react at 120-130 °C for 1-2 h, cool down to 80-90 °C and react for 4-5 h to obtain a reaction product. Then add the reaction product to a mixed solution of tetrahydrofuran and toluene with a volume ratio of 1:1 at an addition amount of 0.1 g / mL, heat and reflux at 70-80 °C for 30-40 min, filter and dry to obtain modified resveratrol. Add the modified resveratrol to epoxy resin E51 and mix evenly to obtain the modified epoxy resin.

[0014] Preferably, in step (1), the heating and stirring reaction temperature is 80 - 90 °C, the speed is 80 - 100 rpm, and the time is 2 - 3 h.

[0015] Preferably, in step (2), the addition amount of 40 wt% sodium hydroxide solution in the mixed solution obtained in step (1) is 0.7 - 0.8 g / mL.

[0016] Preferably, the composite nano - filler comprises the following components in parts by weight: 3.2 - 3.6 parts of γ - aminopropyltriethoxysilane, 4 - 5 parts of mica iron oxide, 1.2 - 1.6 parts of zinc nitrate, and 2.9 - 3.8 parts of 2 - methylimidazole.

[0017] Preferably, the preparation method of the composite nano - filler specifically comprises the following steps:

[0018] S1. Add mica iron oxide into a 95 wt% ethanol solution, add γ - aminopropyltriethoxysilane, adjust the pH to 4.5 - 5.5, and carry out a heating and stirring reaction to obtain modified mica iron oxide;

[0019] S2. Add zinc nitrate into methanol, stir at 200 - 300 rpm for 8 - 15 min to obtain a zinc nitrate dispersion liquid, and then add the modified mica iron oxide obtained in S1 into the zinc nitrate dispersion liquid, stir at 300 - 400 rpm for 2 - 3 h to obtain a modified mica iron oxide dispersion liquid;

[0020] S3. Add 2 - methylimidazole into the modified mica iron oxide dispersion liquid obtained in S2, carry out a heating and stirring reaction, stand for 12 h, filter and dry to obtain the composite nano - filler.

[0021] Preferably, in S1, the heating and stirring reaction temperature is 45 - 55 °C, the speed is 60 - 80 rpm, and the time is 10 - 16 h.

[0022] Preferably, in S3, the heating and stirring reaction temperature is 80 - 120 °C, the speed is 40 - 60 rpm, and the time is 80 - 120 min.

[0023] The present invention also provides a preparation method of an epoxy anticorrosive coating, which specifically comprises the following steps:

[0024] Mix the modified epoxy resin and the diluent, add them into a reactor, heat in a water bath at 25 - 30 °C for 20 min, add the additives, disperse at 2500 - 3000 rpm for 10 min, add the composite nano - filler, disperse at 3000 - 4000 rpm for 30 min, and finally add the curing agent and mix evenly to obtain the epoxy anticorrosive coating.

[0025] The beneficial effects achieved by the present invention are as follows: The present invention modifies resveratrol with epichlorohydrin, epoxidizes the phenolic hydroxyl group on resveratrol to obtain epoxidized resveratrol, which has both double bonds and epoxy groups. 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide has a phosphazene ring structure, and phosphorus has a pair of lone electrons, which undergoes nucleophilic addition with epoxidized resveratrol to obtain modified resveratrol. Subsequently, it is mixed with epoxy resin E51 to obtain modified epoxy resin, improving the flame retardancy and heat resistance of the resin. At the same time, mica iron oxide is modified with γ-aminopropyltriethoxysilane, and zinc ions are adsorbed on the surface of mica iron oxide, enabling 2-methylimidazole to in-situ polymerize on its surface to form an organic layer, improving the compatibility between the filler and the resin, optimizing the dispersion effect of the filler in the resin system, and realizing the covalent bonding between the resin matrix and the functional filler through the ring-opening of the epoxy group by imidazole, enhancing the adhesion strength of the interface, thereby improving the mechanical properties. At the same time, the uniformly dispersed mica iron oxide blocks the diffusion of small molecules, realizing the improvement of the excellent hygrothermal aging resistance and salt spray corrosion resistance of the epoxy resin coating, and obtaining an epoxy anti-corrosion coating with excellent comprehensive performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a graph showing the results of thermal stability tests for Examples 1-3 and Comparative Example 1 of the present invention;

[0027] Figure 2 It is a graph showing the results of salt spray tests for Examples 1-3 and Comparative Examples 1-2 of the present invention;

[0028] Figure 3 It is a graph showing the results of impact resistance tests for Examples 1-3 and Comparative Examples 1-2 of the present invention;

[0029] Figure 4 It is a graph showing the results of adhesion tests for Examples 1-3 and Comparative Examples 1-2 of the present invention;

[0030] Figure 5 It is a physical picture of the experimental steel plate before and after spraying of the present invention, where a is the physical picture of the steel plate, b is the physical picture of the steel plate after the first spraying, c is the physical picture of the steel plate after the second spraying, and d is the physical picture of the steel plate after the third spraying.

[0031] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention, and do not constitute a limitation to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0032] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0033] Unless otherwise defined, all professional and scientific terms used herein have the same meaning as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to the described content can be applied to the present invention. The preferred implementation methods and materials described herein are only for demonstration purposes and do not limit the content of this application.

[0034] The experimental methods in the following embodiments are all conventional methods unless otherwise specified; the test materials used in the following embodiments are all obtained from commercial channels unless otherwise specified.

[0035] Example 1

[0036] An epoxy anticorrosive coating comprises the following components in parts by weight: 110 parts of modified epoxy resin, 19 parts of diluent, 0.9 part of composite nano filler, 10 parts of auxiliary agent, and 8 parts of curing agent.

[0037] The modified epoxy resin is prepared from the following components in parts by weight: 16 parts of resveratrol, 1.2 parts of benzyltriethylammonium chloride, 210 parts of epichlorohydrin, 28 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and 86 parts of epoxy resin E51.

[0038] The preparation method of the modified epoxy resin specifically comprises the following steps:

[0039] (1) Add resveratrol into a reactor, then add benzyltriethylammonium chloride and epichlorohydrin, mix evenly, and under nitrogen protection, heat at 80 °C and stir at 80 rpm for 2 h to obtain a mixed solution;

[0040] (2) Drop 40 wt% sodium hydroxide solution into the mixed solution obtained in step (1) at 0.7 g / mL, continue to react for 1 h, filter, separate the liquid, take the organic layer, and dry to obtain epoxidized resveratrol. Add the epoxidized resveratrol into 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, heat and react at 120 °C for 1 h, cool down to 80 °C and react for 4 h to obtain a reactant. Then add the reactant into a mixed solution of tetrahydrofuran and toluene with a volume ratio of 1:1 at an addition amount of 0.1 g / mL, heat and reflux at 70 °C for 30 min, filter and dry to obtain modified resveratrol. Add the modified resveratrol into epoxy resin E51 and mix evenly to obtain the modified epoxy resin.

[0041] The composite nano-filler comprises components in the following parts by weight: 3.2 parts of γ-aminopropyltriethoxysilane, 4 parts of mica iron oxide, 1.2 parts of zinc nitrate, and 2.9 parts of 2-methylimidazole.

[0042] The preparation method of the composite nano-filler specifically comprises the following steps:

[0043] S1. Add mica iron oxide into a 95 wt% ethanol solution, add γ-aminopropyltriethoxysilane, adjust the pH to 4.5, heat at 45 °C and stir at 60 rpm for 10 h to obtain modified mica iron oxide;

[0044] S2. Add zinc nitrate into methanol, stir at 200 rpm for 8 min to obtain a zinc nitrate dispersion liquid. Subsequently, add the modified mica iron oxide obtained in S1 into the zinc nitrate dispersion liquid, and stir at 300 rpm for 2 h to obtain a modified mica iron oxide dispersion liquid;

[0045] S3. Add 2-methylimidazole into the modified mica iron oxide dispersion liquid obtained in S2, heat at 80 °C and stir at 40 rpm for 80 min, then let it stand for 12 h, filter and dry to obtain the composite nano-filler.

[0046] The present invention also provides a preparation method of an epoxy anti-corrosion coating, which specifically comprises the following steps:

[0047] Mix the modified epoxy resin and dodecyl glycidyl ether, add them into a reactor, heat in a water bath at 25 °C for 20 min, add an auxiliary agent obtained by uniformly mixing a defoaming agent BYK-A530 and a toughening agent D-1217 in a mass ratio of 1:90, disperse at 2500 rpm for 10 min, add the composite nano-filler, disperse at 3000 rpm for 30 min, and finally add polyamide 651 and mix evenly to obtain the epoxy anti-corrosion coating.

[0048] Example 2

[0049] An epoxy anti-corrosion coating comprises components in the following parts by weight: 130 parts of modified epoxy resin, 22 parts of diluent, 1.2 parts of composite nano-filler, 12 parts of auxiliary agent, and 10 parts of curing agent.

[0050] The modified epoxy resin is prepared from components in the following parts by weight: 18 parts of resveratrol, 1.4 parts of benzyltriethylammonium chloride, 220 parts of epichlorohydrin, 30 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and 92 parts of epoxy resin E51.

[0051] The preparation method of the modified epoxy resin specifically comprises the following steps:

[0052] (1) Resveratrol was added to a reactor, followed by the addition of benzyltriethylammonium chloride and epichlorohydrin. After mixing evenly, under nitrogen protection, the mixture was heated at 90 °C and stirred at 100 rpm for 3 h to obtain a mixed solution.

[0053] (2) A 40 wt% sodium hydroxide solution was added dropwise to the mixed solution obtained in step (1) at a rate of 0.8 g / mL, and the reaction was continued for 1 h. After filtration, liquid separation, taking the organic layer, and drying, epoxidized resveratrol was obtained. The epoxidized resveratrol was added to 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and the reaction was carried out by heating at 130 °C for 2 h and then cooling to 90 °C for 5 h to obtain a reaction product. Subsequently, the reaction product was added to a mixed solution of tetrahydrofuran and toluene with a volume ratio of 1:1 at an addition amount of 0.1 g / mL, and the mixture was heated under reflux at 80 °C for 40 min. After filtration and drying, modified resveratrol was obtained. The modified resveratrol was added to epoxy resin E51 and mixed evenly to obtain a modified epoxy resin.

[0054] The composite nano-filler comprises the following components in parts by weight: 3.6 parts of γ-aminopropyltriethoxysilane, 5 parts of micaceous iron oxide, 1.6 parts of zinc nitrate, and 3.8 parts of 2-methylimidazole.

[0055] The preparation method of the composite nano-filler specifically comprises the following steps:

[0056] S1. Micaceous iron oxide was added to a 95 wt% ethanol solution, and γ-aminopropyltriethoxysilane was added. The pH was adjusted to 5.5, and the mixture was heated at 55 °C and stirred at 80 rpm for 16 h to obtain modified micaceous iron oxide.

[0057] S2. Zinc nitrate was added to methanol and stirred at 300 rpm for 15 min to obtain a zinc nitrate dispersion. Subsequently, the modified micaceous iron oxide obtained in S1 was added to the zinc nitrate dispersion, and the mixture was stirred at 400 rpm for 3 h to obtain a modified micaceous iron oxide dispersion.

[0058] S3. 2-Methylimidazole was added to the modified micaceous iron oxide dispersion obtained in S2, and the mixture was heated at 120 °C and stirred at 60 rpm for 120 min. After standing for 12 h, filtration and drying were carried out to obtain the composite nano-filler.

[0059] The present invention also provides a preparation method of an epoxy anticorrosive coating, which specifically comprises the following steps:

[0060] Mix the modified epoxy resin and dodecyl glycidyl ether, add them to a reactor, heat them in a water bath at 30°C for 20 min, add the defoamer BYK-A530 and the toughening agent D-1217, which are uniformly mixed in a mass ratio of 1:90 to obtain an auxiliary agent, disperse it at 3000 rpm for 10 min, add the composite nano-filler, disperse it at 4000 rpm for 30 min, and finally add polyamide 651 and mix evenly to obtain the epoxy anti-corrosion coating.

[0061] Example 3

[0062] An epoxy anti-corrosion coating comprises the following components in parts by weight: 120 parts of modified epoxy resin, 20 parts of diluent, 1 part of composite nano-filler, 11 parts of auxiliary agent, and 9 parts of curing agent.

[0063] The modified epoxy resin is prepared from the following components in parts by weight: 17 parts of resveratrol, 1.3 parts of benzyltriethylammonium chloride, 215 parts of epichlorohydrin, 29 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and 90 parts of epoxy resin E51.

[0064] The preparation method of the modified epoxy resin specifically comprises the following steps:

[0065] (1) Add resveratrol to a reactor, then add benzyltriethylammonium chloride and epichlorohydrin, mix evenly, under nitrogen protection, heat at 85°C and stir at 90 rpm for 2.5 h to obtain a mixed solution;

[0066] (2) Drop 40 wt% sodium hydroxide solution into the mixed solution obtained in step (1) at 0.75 g / mL, continue to react for 1 h, filter, separate the liquid, take the organic layer, dry it to obtain epoxidized resveratrol, add the epoxidized resveratrol to 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, heat and react at 125°C for 1.5 h, cool down to 85°C and react for 4.5 h to obtain a reactant, then add the reactant to a mixed solution of tetrahydrofuran and toluene with a volume ratio of 1:1 at an addition amount of 0.1 g / mL, heat and reflux at 75°C for 35 min, filter and dry to obtain modified resveratrol, and add the modified resveratrol to epoxy resin E51 and mix evenly to obtain the modified epoxy resin.

[0067] The composite nano-filler comprises the following components in parts by weight: 3.4 parts of γ-aminopropyltriethoxysilane, 4.5 parts of mica iron oxide, 1.4 parts of zinc nitrate, and 3 parts of 2-methylimidazole.

[0068] The preparation method of the composite nano-filler specifically comprises the following steps:

[0069] S1. Add mica iron oxide into an ethanol solution with a concentration of 95 wt%, add γ-aminopropyltriethoxysilane, adjust the pH to 5, heat at 50 °C and stir at 70 rpm for 12 h to obtain modified mica iron oxide;

[0070] S2. Add zinc nitrate into methanol, stir at 250 rpm for 12 min to obtain a zinc nitrate dispersion. Subsequently, add the modified mica iron oxide obtained in S1 into the zinc nitrate dispersion, stir at 350 rpm for 2.5 h to obtain a modified mica iron oxide dispersion;

[0071] S3. Add 2-methylimidazole into the modified mica iron oxide dispersion obtained in S2, heat at 100 °C and stir at 50 rpm for 100 min, then let it stand for 12 h, filter and dry to obtain the composite nano filler.

[0072] The present invention also provides a preparation method of an epoxy anti-corrosion coating, which specifically includes the following steps:

[0073] Mix the modified epoxy resin and dodecyl glycidyl ether, add them into a reactor, heat in a water bath at 28 °C for 20 min, add an auxiliary agent obtained by uniformly mixing a defoaming agent BYK-A530 and a toughening agent D-1217 in a mass ratio of 1:90, disperse at 2800 rpm for 10 min, add the composite nano filler, disperse at 3500 rpm for 30 min, and finally add polyamide 651 and mix evenly to obtain the epoxy anti-corrosion coating.

[0074] Comparative Example 1

[0075] This comparative example provides a coating, the difference from Example 1 is only that resveratrol is used to replace the modified resveratrol in the components, and the other components and component contents are the same as those in Example 1.

[0076] Comparative Example 2

[0077] This comparative example provides a coating, the difference from Example 1 is only that 2-methylimidazole is not contained in the components, and the other components and component contents are the same as those in Example 1.

[0078] Experimental Example

[0079] 1. Stability test

[0080] Perform a thermal stability test on the epoxy anti-corrosion coatings prepared in Examples 1-3 and Comparative Example 1 of the present invention. Using a thermogravimetric analyzer, with a heating rate of 20 °C / min, heat from 20 °C to 600 °C in a nitrogen atmosphere, and record T5% (the temperature at which the mass loss is 5%) and T90% (the temperature at which the mass loss is 90%).

[0081] Figure 1This is the graph showing the results of the thermal stability tests for Examples 1-3 and Comparative Example 1 of the present invention. As shown in the figure, the T5% values of Examples 1-3 and Comparative Example 1 are 243 °C, 241 °C, 245 °C, and 193 °C respectively, and the T90% values are 656 °C, 661 °C, 653 °C, and 514 °C respectively. The modification of resveratrol improves the thermal stability of the coating.

[0082] 2. Salt spray test

[0083] Examples 1-3 and Comparative Examples 1-2 were coated on steel plates with a coating thickness of 80 μm. After drying, a cutter was used to cut through the coating film until the steel plate was exposed. The scratch was more than 20 mm away from any edge of the steel plate. A 5% NaCl solution with a pH value of 6.5 - 7.2 was used, and continuous spraying was carried out at a test temperature of 35 ± 2 °C. The corrosion situation was recorded, and the corrosion time was the time when rust spots appeared on the plate surface or the rust spread at the scratched line exceeded 3 cm.

[0084] Figure 2 This is the graph showing the results of the salt spray tests for Examples 1-3 and Comparative Examples 1-2 of the present invention. As shown in the figure, the corrosion times of Examples 1-3 and Comparative Examples 1-2 are 1216.4 h, 1223.1 h, 1235.8 h, 936.7 h, and 1016.7 h respectively. The corrosion times of Examples 1-3 are significantly longer than those of Comparative Examples 1-2, indicating that the corrosion resistance of Examples 1-3 is stronger than that of Comparative Examples 1-2. The modification of resveratrol and the use of 2-methylimidazole improve the corrosion resistance of the epoxy coating.

[0085] 3. Impact resistance test

[0086] Examples 1-3 and Comparative Examples 1-2 were coated on steel plates. After complete curing, they were placed on a film impact tester. The height of the weight was adjusted and freely dropped onto the punch head, and the coating was observed for cracks, wrinkles, and peeling phenomena. If the above phenomena were not observed, the test was repeated with a 1 cm increase in height until the above phenomena were observed, and the maximum impact height was recorded.

[0087] Figure 3 This is the graph showing the results of the impact resistance tests for Examples 1-3 and Comparative Examples 1-2 of the present invention. As shown in the figure, the maximum impact heights of Examples 1-3 and Comparative Examples 1-2 are 45 cm, 46 cm, 45 cm, 32 cm, and 36 cm respectively. The maximum impact heights of Examples 1-3 are significantly greater than those of Comparative Examples 1-2, indicating that the impact resistance of Examples 1-3 is stronger than that of Comparative Examples 1-2. The modification of resveratrol and the use of 2-methylimidazole improve the impact resistance of the epoxy coating.

[0088] 4. Adhesion test

[0089] Examples 1-3 and Comparative Examples 1-2 were coated on a steel plate. After the coating was completely cured, the adhesion test was carried out using a PosiTest adhesion tester according to the standard GB / T5210-2006. During the measurement, the pulling force was increased uniformly until the coating was pulled off, and the pulling force value displayed on the instrument at this time was recorded as the maximum adhesion force.

[0090] Figure 4 This is the graph of the adhesion test results of Examples 1-3 and Comparative Examples 1-2 of the present invention; as shown in the figure, the maximum adhesion forces of Examples 1-3 and Comparative Examples 1-2 are 17.1 MPa, 17.6 MPa, 17.3 MPa and 11.6 MPa, 13.4 MPa respectively. The maximum adhesion forces of Examples 1-3 are significantly greater than those of Comparative Examples 1-2, indicating that the adhesion ability of Examples 1-3 is stronger than that of Comparative Examples 1-2. The use of resveratrol modification and 2-methylimidazole improves the adhesion ability of the epoxy coating.

[0091] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention.

[0092] The present invention and its embodiments have been described above. Such description is not restrictive. What is shown in the drawings is only one of the embodiments of the present invention, and the actual application is not limited thereto. Generally speaking, if those of ordinary skill in the art are inspired by it and design similar ways and embodiments to this technical solution without creative work without departing from the purpose of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. An epoxy anticorrosive coating, characterized in that: The invention comprises the following components in parts by weight: 110-130 parts of modified epoxy resin, 19-22 parts of diluent, 0.9-1.2 parts of composite nano filler, 10-12 parts of auxiliary agent, and 8-10 parts of curing agent; The modified epoxy resin is prepared from the following components in parts by weight: 16-18 parts of resveratrol, 1.2-1.4 parts of benzyltriethylammonium chloride, 210-220 parts of epichlorohydrin, 28-30 parts of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, and 86-92 parts of epoxy resin E51; The composite nano filler comprises the following components in parts by weight: 3.2-3.6 parts of gamma-aminopropyltriethoxysilane, 4-5 parts of mica iron oxide, 1.2-1.6 parts of zinc nitrate, and 2.9-3.8 parts of 2-methylimidazole.

2. A method for preparing the epoxy anticorrosive coating according to claim 1, characterized in that: The specific steps include: The modified epoxy resin and the diluent are mixed, added into a reactor, heated in a water bath at 25-30°C for 20 minutes, an auxiliary agent is added, dispersed at 2500-3000rpm for 10 minutes, a composite nanofiller is added, dispersed at 3000-4000rpm for 30 minutes, and finally a curing agent is added and mixed evenly to obtain an epoxy anticorrosive coating.

3. The method for preparing the epoxy anticorrosive coating according to claim 2, characterized in that: The diluent includes one of dodecyl glycidyl ether, propylene oxide benzyl ether and ethylene glycol glycidyl ether; the auxiliary agent is a defoamer BYK-A530 and a toughening agent D-1217 uniformly mixed in a mass ratio of 1:80-100; and the curing agent includes one of polyamide 651, polyamide 650 and polyamide 400.

4. The method for preparing the epoxy anticorrosive coating according to claim 3, characterized in that: The preparation method of the modified epoxy resin specifically comprises the following steps: (1) adding resveratrol into a reactor, and then adding benzyltriethylammonium chloride and epichlorohydrin, mixing them evenly, and heating and stirring under nitrogen protection to react to obtain a mixed solution; (2) Add 40 wt % sodium hydroxide solution dropwise to the mixed solution obtained in step (1), continue the reaction for 1 h, filter, separate the liquid, take the organic layer, and dry to obtain epoxidized resveratrol, add the epoxidized resveratrol to 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, heat at 120-130° C. for reaction for 1-2 h, cool to 80-90° C. for reaction for 4-5 h, and obtain the reactant, then add the reactant in an amount of 0.1 g / mL to a mixture of tetrahydrofuran and toluene in a volume ratio of 1:1, heat under reflux at 70-80° C. for 30-40 min, filter, and dry to obtain modified resveratrol, add the modified resveratrol to epoxy resin E51 and mix evenly to obtain modified epoxy resin.

5. The method for preparing the epoxy anticorrosive coating according to claim 4, characterized in that: The preparation method of the composite nanofiller specifically comprises the following steps: S1, adding mica iron oxide to a 95wt% ethanol solution, adding γ-aminopropyltriethoxysilane, adjusting the pH to 4.5-5.5, heating and stirring to react, to obtain modified mica iron oxide; S2, adding zinc nitrate to methanol, stirring at 200-300 rpm for 8-15 min to obtain a zinc nitrate dispersion, then adding the modified mica iron oxide obtained in S1 to the zinc nitrate dispersion, stirring at 300-400 rpm for 2-3 h to obtain a modified mica iron oxide dispersion; S3. Add 2-methylimidazole to the modified mica iron oxide dispersion obtained in S2, heat and stir to react, let stand for 12 hours, filter and dry to obtain a composite nanofiller.

6. The method for preparing the epoxy anticorrosive coating according to claim 5, characterized in that: In step (1), the heating and stirring reaction temperature is 80-90°C, the speed is 80-100 rpm, and the time is 2-3 hours.

7. The method for preparing the epoxy anticorrosive coating according to claim 6, characterized in that: In step (2), the amount of 40 wt% sodium hydroxide solution added to the mixed solution obtained in step (1) is 0.7-0.8 g / mL.

8. The method for preparing the epoxy anticorrosive coating according to claim 7, characterized in that: In S1, the heating and stirring reaction temperature is 45-55°C, the speed is 60-80 rpm, and the time is 10-16 h.

9. The method for preparing the epoxy anticorrosive coating according to claim 8, characterized in that: In S3, the heating and stirring reaction temperature is 80-120°C, the speed is 40-60rpm, and the time is 80-120min.

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