A corrosion protection and thermal insulation coating composition and method of making the same

Abstract

The present application relates to the field of paint, and discloses a kind of anticorrosive thermal insulation paint composition and paint and the preparation method of coating thereof.The anticorrosive thermal insulation paint composition contains microbead layered composite metal hydroxide composite material, epoxy resin and curing agent, the microbead layered composite metal hydroxide composite material includes microbead and layered composite metal hydroxide coated on the surface of the microbead;The microbead is glass microbead and / or ceramic microbead;The interlayer anion of the layered composite metal hydroxide is corrosion-inhibiting anion.The paint prepared using the anticorrosive paint composition has good anticorrosive thermal insulation effect.

Description

Technical Field

[0001] This invention relates to the field of coatings, and more specifically to an anti-corrosion and heat-insulating coating composition and a method for preparing the coating and its coating layer. Background Technology

[0002] Layered metal hydroxides (LDHs), also known as hydrotalcites, possess a three-dimensional crystal structure formed by the longitudinally ordered extension of octahedral two-dimensional layers at the nanoscale. These layers are composed of two or more divalent and trivalent metal hydroxides. Anions between the layers compensate for the charge balance. The interlayer anions in LDHs are exchangeable and can be replaced by other anions during the preparation process, thus serving as a carrier for corrosion inhibitors. The corrosion inhibitor anions contained within the LDH layers are released upon stimulation by external corrosive media, and can simultaneously capture corrosive anionic substances such as Cl-. - SO4 2- Such as, thus playing a role in corrosion prevention, but the currently prepared layered composite metal hydroxides all have serious stacking, resulting in a small specific surface area, which inhibits their effect of capturing corrosive anions; ceramic and glass microspheres have light weight, low thermal conductivity, thermal insulation properties and good dispersibility, and can be used as thermal insulation fillers.

[0003] Patent application CN104877484B discloses a water-based energy-saving thermal insulation coating for petrochemical tanks, prepared from a modified polymer emulsion compound of silica sol and polymer emulsion. This coating primarily functions as thermal insulation, but it does not address the issue of under-insulation corrosion that easily occurs in steel structures below 200℃. Patent application CN111534131B discloses a SiO2 aerogel-modified thermal insulation coating, which similarly does not provide a targeted solution for under-insulation corrosion. Patent application CN111019424B discloses an epoxy-silicone resin thermal insulation coating based on polymer structure design principles. This coating achieves thermal insulation performance while also possessing certain anti-corrosion properties; however, its synthesis process is relatively complex and costly. The petrochemical industry requires large-scale use of thermal insulation coatings, and economic viability limits the coating's application. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems of existing anti-corrosion and thermal insulation coatings, such as complex synthesis processes, high costs, and easy corrosion of steel structures such as petrochemical and thermal pipelines under the coating at temperatures below 200°C. This invention provides an anti-corrosion and thermal insulation coating that can improve the corrosion protection performance of steel structures while meeting thermal insulation requirements. At the same time, its preparation process is simple and environmentally friendly.

[0005] To achieve the above objectives, the present invention provides an anti-corrosion and thermal insulation coating composition, wherein the anti-corrosion and thermal insulation coating composition comprises a microsphere layered composite metal hydroxide composite material, an epoxy resin and a curing agent, wherein the microsphere layered composite metal hydroxide composite material includes microspheres and layered composite metal hydroxides coated on the surface of the microspheres;

[0006] The microspheres are glass microspheres and / or ceramic microspheres;

[0007] The interlayer anions of the layered composite metal hydroxide are corrosion-inhibiting anions.

[0008] Preferably, the weight ratio of the epoxy resin to the curing agent is 1:0.3-0.5.

[0009] Preferably, the weight ratio of the epoxy resin and the microsphere layered composite metal hydroxide is 1:0.01-0.2.

[0010] Preferably, the epoxy resin is an aqueous epoxy resin.

[0011] Preferably, the curing agent is a water-based epoxy curing agent and / or an organosilicon-modified curing agent.

[0012] Preferably, the microspheres have a particle size of 0.1-500 μm, more preferably 50-150 μm.

[0013] Preferably, the corrosion-inhibiting anion is selected from MoO4. 2- PO4 3- HCOO - CH3(CH2) 11 OSO3 - NO3 - and NO2 - One or more of them.

[0014] Preferably, the metal elements in the layered composite metal hydroxide are metal M and metal N; metal M is selected from one or more of Mg, Ni, Cu, Zn and Ca, and metal N is selected from one or more of Al, Co, Fe, Cr and Ga.

[0015] Preferably, the preparation method of the microbead layered composite metal hydroxide composite material includes the following steps:

[0016] (1) Mix microbeads, metal precursor, solvent and substances that can form carbonate ions in solution to obtain a mixture, adjust the pH of the mixture to >7, and then carry out the reaction.

[0017] (2) Perform solid-liquid separation and heat treatment on the material obtained in step (1);

[0018] (3) Mix the material obtained by heat treatment in step (2) with a solution containing corrosion inhibitory compound, adjust the pH value of the solution to >7, and then carry out the reaction.

[0019] Preferably, the metal precursor is a metal M precursor and a metal N precursor; the molar ratio of the metal M precursor to the metal N precursor is 1:0.2-5, based on the metal content.

[0020] Preferably, the weight ratio of the microspheres to the metal M precursor is 1:0.5-5.

[0021] Preferably, the anti-corrosion and heat-insulating coating composition further contains functional pigments.

[0022] Preferably, the weight ratio of the epoxy resin to the functional pigment is 1:0.1-0.3.

[0023] Preferably, the functional pigment is selected from one or more of titanium dioxide, ultrafine heavy calcium carbonate, calcium carbonate, barium sulfate, talc, bentonite, and quartz powder.

[0024] Preferably, the anti-corrosion and thermal insulation coating composition further contains additives.

[0025] Preferably, the weight ratio of the epoxy resin to the additive is 1:0.05-0.1.

[0026] Preferably, the additive is selected from one or more of dispersants, defoamers, thickeners, antifungals, and aerogels.

[0027] A second aspect of the present invention provides an anti-corrosion and thermal insulation coating, which is obtained by mixing the above-mentioned anti-corrosion and thermal insulation coating composition with water.

[0028] Preferably, the weight ratio of the epoxy resin to water is 1:0.3-0.5.

[0029] The third aspect of the present invention provides a method for preparing an anti-corrosion and heat-insulating coating, wherein the anti-corrosion and heat-insulating coating is obtained by applying the above-mentioned anti-corrosion and heat-insulating coating to the surface of a substrate and then curing it.

[0030] Preferably, the curing conditions include a temperature of 30-60°C and a time of 24-60 hours.

[0031] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0032] (1) In this invention, the microbead layered composite metal hydroxide composite material has good dispersion performance and good performance in capturing corrosive anions such as chloride ions. At the same time, the glass microbeads or ceramic microbeads also have heat preservation performance. Therefore, when the microbead layered composite metal hydroxide composite material is used in coatings, it can not only improve the anti-corrosion performance of the coatings, but also the coatings have a heat preservation effect.

[0033] (2) The anti-corrosion and heat-insulating coating of the present invention has good corrosion protection performance for steel materials such as petrochemical and heat pipelines at temperatures below 200℃;

[0034] (3) The technical solution described in this invention is green and environmentally friendly, with a simple process and low cost. Attached Figure Description

[0035] Figure 1 The image shows the test results of a neutral salt spray test conducted on a 5cm×2.5cm×0.2cm 20# steel sheet using the coating prepared in Example 1.

[0036] Figure 2 The figure shows the test results of a neutral salt spray test on a 20# steel sheet measuring 5cm×2.5cm×0.2cm, with the coating prepared in Comparative Example 1 applied to the sheet.

[0037] Figure 3 The image shows the electrochemical impedance spectroscopy results of the coating prepared in Example 1 applied to a 1cm×1cm×0.5cm Q235 carbon steel electrode at an artificial defect on the Q235 carbon steel electrode. Detailed Implementation

[0038] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0039] The endpoints and any values ​​of the ranges 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 endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0040] The present invention provides an anti-corrosion and thermal insulation coating composition, wherein the anti-corrosion and thermal insulation coating composition comprises a microsphere layered composite metal hydroxide composite material, an epoxy resin and a curing agent, wherein the microsphere layered composite metal hydroxide composite material comprises microspheres and layered composite metal hydroxides coated on the surface of the microspheres;

[0041] The microspheres are glass microspheres and / or ceramic microspheres;

[0042] The interlayer anions of the layered composite metal hydroxide are corrosion-inhibiting anions.

[0043] In this invention, there are no special requirements for the "microbeads"; either "hollow microbeads" or "solid microbeads" are acceptable.

[0044] In a preferred embodiment, the microspheres are glass microspheres and / or ceramic microspheres.

[0045] In a preferred embodiment, in order to further improve the dispersion performance of the layered composite metal hydroxide, the particle size of the microspheres is 0.1-500 μm, more preferably 50-150 μm.

[0046] In this invention, the term "corrosion-inhibiting anion" refers to "an ion that can undergo ion exchange with corrosive anions (such as chloride ions) and capture corrosive anions in the environment."

[0047] In a preferred embodiment, to further improve the performance of the layered composite metal hydroxide in capturing corrosive anions (e.g., chloride ions), the corrosion-inhibiting anion is selected from MoO4. 2- PO4 3- HCOO - CH3(CH2) 11 OSO3 - NO3 - and NO2 - One or more of them.

[0048] In a preferred embodiment, the weight ratio of the epoxy resin to the curing agent is 1:0.3-0.5; specifically, it can be 1:0.3, 1:0.4 or 1:0.5.

[0049] In a preferred embodiment, the weight ratio of the epoxy resin and the microsphere layered composite metal hydroxide material is 1:0.01-0.2; specifically, it can be 1:0.01, 1:0.05, 1:0.1, 1:0.12, 1:0.15 or 1:0.2.

[0050] In a preferred embodiment, to improve the compatibility between the anti-corrosion and thermal insulation coating compositions, the epoxy resin is a water-based epoxy resin.

[0051] In a preferred embodiment, the curing agent is a water-based epoxy curing agent and / or an organosilicon-modified curing agent.

[0052] In a preferred embodiment, the waterborne epoxy curing agent is selected from one or more of polyamide curing agents, fatty amine curing agents, and acid anhydride curing agents.

[0053] In a preferred embodiment, the organosilicon-modified curing agent is a siloxane coupling type organosilicon-modified curing agent and / or a siloxane-substituted side-group type organosilicon-modified curing agent.

[0054] In a preferred embodiment, the metal elements in the layered composite metal hydroxide are metal M and metal N; metal M is selected from one or more of Mg, Ni, Cu, Zn and Ca, and metal N is selected from one or more of Al, Co, Fe, Cr and Ga.

[0055] In a preferred embodiment, the preparation method of the microbead layered composite metal hydroxide composite material includes the following steps:

[0056] (1) Mix microbeads, metal precursor, solvent and substances that can form carbonate ions in solution to obtain a mixture, adjust the pH of the mixture to >7, and then carry out the reaction.

[0057] (2) Perform solid-liquid separation and heat treatment on the material obtained in step (1);

[0058] (3) Mix the material obtained by heat treatment in step (2) with a solution containing corrosion inhibitory compound, adjust the pH value of the solution to >7, and then carry out the reaction.

[0059] In a preferred embodiment, the preparation method of the microbead layered composite metal hydroxide composite material further includes pretreatment of the microbeads to remove grease from the surface of the microbeads.

[0060] In a specific embodiment, the microbeads and ethanol are mixed, stirred, and then filtered, washed, and dried.

[0061] In this invention, there are no special requirements for the "substance capable of forming carbonate ions in solution", as long as it can provide carbonate ions in solution.

[0062] In a preferred embodiment, in step (1), the substance capable of forming carbonate ions in the solution can be a carbonate, a bicarbonate, or carbonic acid; specifically, it can be one or more of sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, and potassium bicarbonate.

[0063] In this invention, there are no special requirements for the amount of the substance that can form carbonate ions in the solution, as long as microsphere layered composite metal hydroxide can be obtained after solid-liquid separation in step (2) and the interlayer anion is carbonate.

[0064] In a preferred embodiment, in step (1), the metal precursor is a metal M precursor and a metal N precursor; the molar ratio of the metal M precursor to the metal N precursor is 1:0.2-5, calculated as metals; specifically, the molar ratio of the metal M precursor to the metal N precursor can be 1:0.2, 1:0.5, 1:1, 1:2, 1:3, 1:4 or 1:5.

[0065] In a preferred embodiment, in order to further improve the dispersion performance of the layered composite metal hydroxide, in step (1), the weight ratio of the microspheres to the metal M precursor is 1:0.5-5. Specifically, the weight ratio of the microspheres to the metal M precursor can be 1:0.5, 1:1, 1:2, 1:3, 1:4 or 1:5.

[0066] In a preferred embodiment, in order to improve the efficiency of the reaction, in step (1), the pH value of the mixture is adjusted to ≥8, and more preferably, the pH value of the mixture is adjusted to 9-10.

[0067] In a preferred embodiment, the heat treatment conditions in step (2) include: a temperature of 550-650°C and a time of 3-8 hours; specifically, the temperature can be 550°C, 600°C or 650°C; and the time can be 3 hours, 5 hours or 8 hours.

[0068] In this invention, the "corrosion-inhibiting compound" refers to a substance capable of providing corrosion-inhibiting anions.

[0069] In this invention, there are no special requirements for the amount of the corrosion inhibitory compound, as long as a micro-bead layered composite metal hydroxide is obtained after the reaction in step (3) and the interlayer anion is a corrosion inhibitory anion.

[0070] In a preferred embodiment, in order to improve the efficiency of the reaction, in step (3), the pH value of the solution is adjusted to ≥8, more preferably, the pH value of the solution is adjusted to 9-10; specifically, it can be 9, 9.5 or 10.

[0071] The microsphere layered composite metal hydroxide prepared by the method of this invention has an intermediate product obtained by solid-liquid separation in step (2) that is a microsphere layered composite metal hydroxide with carbonate ions as the interlayer anion. After heat treatment, the carbonate ions in the interlayer decompose and leave cavities, thereby introducing any desired corrosion-inhibiting anion into the layered composite metal hydroxide. Since the bonding force between carbonate ions and the cation layer of the layered composite metal hydroxide is strong, the microsphere layered composite metal hydroxide composite material prepared by the method of this invention does not have special requirements for the anion of the metal precursor.

[0072] In a preferred embodiment, in order to impart color to the coating prepared using the anti-corrosion and thermal insulation coating composition and improve its performance, the anti-corrosion and thermal insulation coating composition also contains functional pigments.

[0073] In a preferred embodiment, the weight ratio of the epoxy resin to the functional pigment is 1:0.1-0.3; specifically, the weight ratio of the epoxy resin to the functional pigment can be 1:0.1, 1:0.2 or 1:0.3.

[0074] In a preferred embodiment, the functional pigment is selected from one or more of titanium dioxide, ultrafine heavy calcium carbonate, calcium carbonate, barium sulfate, talc, bentonite, and quartz powder.

[0075] In a preferred embodiment, to further improve the overall performance of the coating prepared using the anti-corrosion and thermal insulation coating composition, the anti-corrosion and thermal insulation coating composition also contains additives.

[0076] In a preferred embodiment, the weight ratio of the epoxy resin to the additive is 1:0.05-0.1; specifically, the weight ratio of the epoxy resin to the additive can be 1:0.05, 1:0.08, or 1:0.1.

[0077] In a preferred embodiment, the additive is selected from one or more of dispersants, defoamers, thickeners, fungicides, and aerogels.

[0078] According to some embodiments of the present invention, the additives are dispersants, defoamers, thickeners, antifungals, and aerogels.

[0079] In a specific implementation, based on the weight of the additives as 100%, the amount of dispersant is 20wt%, the amount of defoamer is 3wt%, the amount of thickener is 20wt%, the amount of mildew inhibitor is 7wt%, and the amount of aerogel is 50wt%.

[0080] A second aspect of the present invention provides an anti-corrosion and thermal insulation coating, which is obtained by mixing the above-mentioned anti-corrosion and thermal insulation coating composition with water.

[0081] The anti-corrosion and thermal insulation coating of the present invention is obtained by mixing the anti-corrosion and thermal insulation coating composition of the present invention with water, and has good thermal insulation and anti-corrosion properties. The anti-corrosion and thermal insulation coating composition contains microsphere layered composite metal hydroxide. The microsphere layered composite metal hydroxide composite material has good dispersion properties and the ability to capture corrosive anions (such as chloride ions) by coating the microspheres with layered composite metal hydroxide, making the anti-corrosion and thermal insulation coating of the present invention even more superior in terms of thermal insulation and anti-corrosion properties.

[0082] In a preferred embodiment, in order to better integrate the epoxy resin and the curing agent and to make the viscosity of the anti-corrosion and thermal insulation coating more suitable for preparing the anti-corrosion and thermal insulation coating, the weight ratio of the epoxy resin to water is 1:0.3-0.5; specifically, the weight ratio of the epoxy resin to water can be 1:0.3, 1:0.4 or 1:0.5.

[0083] In a preferred embodiment, the preparation method of the anti-corrosion and thermal insulation coating includes the following steps:

[0084] A1: Mix the additives and water under the following conditions: stirring speed of 500-800 r / min and stirring time of 5-10 min;

[0085] A2: Mix the microsphere layered composite metal hydroxide composite material, epoxy resin and functional pigment with the material obtained in step A1. The mixing conditions include: stirring speed of 200-500 r / min and stirring time of 20-30 min.

[0086] The third aspect of the present invention provides a method for preparing an anti-corrosion and heat-insulating coating, wherein the anti-corrosion and heat-insulating coating is obtained by applying the above-mentioned anti-corrosion and heat-insulating coating to the surface of a substrate and then curing it.

[0087] In a preferred embodiment, the curing conditions include: a temperature of 30-60°C and a time of 24-60 hours; specifically, the temperature can be 30°C, 40°C, 50°C, or 60°C; and the time can be 24 hours, 36 hours, 48 ​​hours, or 60 hours.

[0088] The following examples further illustrate the anti-corrosion and thermal insulation coating composition, coating, and preparation method of the coating thereof according to the present invention. The examples are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following examples.

[0089] Table 1

[0090]

[0091]

[0092]

[0093] Example 1

[0094] The specific selection and dosage of raw materials are shown in Table 1;

[0095] Preparation of microbead layered composite metal hydroxide composite material M1:

[0096] (1) Mix ceramic microspheres and ethanol and stir. After stirring for 30 min, filter, wash and dry. Disperse 100 mg of dried ceramic microspheres with a particle size of 100-150 μm in 50 mL of water and stir at 150 r / min for 30 min. After uniform dispersion, add 0.1 g of anhydrous sodium carbonate and sonicate at 500 W for 5 min to obtain solution A1. Disperse 0.25 g of magnesium nitrate hexahydrate and 0.18 g of aluminum nitrate nonahydrate in 20 mL of water and sonicate at 500 W for 10 min to obtain solution B1. Slowly add solution B1 to solution A1 over a period of 20 min. At the same time, add 1 M sodium hydroxide solution to adjust the pH of the mixture to 9. Then react. After the addition is complete, stir at 150 r / min for 60 min.

[0097] (2) The material obtained in step (1) is filtered and washed to obtain intermediate material S1 (SiO2@Mg-Al CO3), and then intermediate material S1 is heat-treated under vacuum at 550℃ for 6h.

[0098] (3) Disperse the material obtained in step (2) in 50 mL of sodium nitrite solution with a concentration of 3 mg / mL, adjust the pH value of the solution to 9, and then carry out the reaction. Stir at 150 r / min for 5 h, and then filter, wash and dry to obtain the final product microbead layered composite metal hydroxide composite material M1 (SiO2@Mg-Al NO2).

[0099] Preparation of anti-corrosion and thermal insulation coating S1:

[0100] A1: Mix the additives and water under the following conditions: stirring speed of 500 r / min and stirring time of 8 min;

[0101] A2: Add the microsphere layered composite metal hydroxide composite material, epoxy resin and functional pigment to the mixture in step A1 and mix them. The mixing conditions include: stirring speed of 200 r / min and stirring time of 30 min.

[0102] Example 2

[0103] Preparation of microbead layered composite metal hydroxide composite material M2:

[0104] The microsphere layered composite metal hydroxide composite material M2 was prepared according to the method of Example 1. The difference is that in step (1), the pH value of the mixture was adjusted to 10 to obtain the final product microsphere layered composite metal hydroxide composite material M2 (SiO2@Mg-Al NO2).

[0105] The specific selection and dosage of raw materials are shown in Table 1;

[0106] Preparation of anti-corrosion and thermal insulation coating S2:

[0107] A1: Mix the additive with 20 parts by weight of water under the following conditions: stirring speed of 600 r / min and stirring time of 5 min;

[0108] A2: Add the microsphere layered composite metal hydroxide material, epoxy resin and functional pigment to the mixture in step A1 and mix them. The mixing conditions include: stirring speed of 300 r / min and stirring time of 30 min.

[0109] Example 3

[0110] The specific selection and dosage of raw materials are shown in Table 1;

[0111] Preparation of anti-corrosion and thermal insulation coating S3:

[0112] A1: Mix the additives and water under the following conditions: stirring speed of 700 r / min and stirring time of 8 min;

[0113] A2: Add the microsphere layered composite metal hydroxide composite material, epoxy resin and functional pigment to the mixture in step A1 and mix them. The mixing conditions include: stirring speed of 400 r / min and stirring time of 30 min.

[0114] Example 4

[0115] Preparation of microbead layered composite metal hydroxide composite material M3:

[0116] The microsphere layered composite metal hydroxide composite material M3 was prepared according to Example 1, except that in step (1), ferric nitrate nonahydrate was used instead of aluminum nitrate nonahydrate to obtain the final product microsphere layered composite metal hydroxide composite material M3 (SiO2@Mg-Fe NO2).

[0117] The specific selection and dosage of raw materials are shown in Table 1;

[0118] Preparation of anti-corrosion and thermal insulation coating S4:

[0119] A1: Mix the additives and water under the following conditions: stirring speed of 800 r / min and stirring time of 5 min;

[0120] A2: Add the microsphere layered composite metal hydroxide composite material, epoxy resin and functional pigment to the mixture in step A1 and mix them. The mixing conditions include: stirring speed of 500 r / min and stirring time of 20 min.

[0121] Example 5

[0122] Preparation of microbead layered composite metal hydroxide composite material M4:

[0123] The microsphere layered composite metal hydroxide composite material M4 was prepared according to Example 1, except that in step (1), nickel nitrate hexahydrate was used instead of magnesium nitrate hexahydrate to obtain the final product microsphere layered composite metal hydroxide composite material M4 (SiO2@Ni-Al NO2).

[0124] The specific selection and dosage of raw materials are shown in Table 1;

[0125] Preparation of anti-corrosion and thermal insulation coating S5:

[0126] A1: Mix the additives and water under the following conditions: stirring speed of 500 r / min and stirring time of 8 min;

[0127] A2: Add the microsphere layered composite metal hydroxide material, epoxy resin and functional pigment to the mixture in step A1 and mix them. The mixing conditions include: stirring speed of 200 r / min and stirring time of 40 min.

[0128] Example 6

[0129] Preparation of microbead layered composite metal hydroxide composite material M5:

[0130] The microsphere layered composite metal hydroxide composite material M5 was prepared according to Example 1, except that in step (3), 50 mL of sodium molybdate solution with a concentration of 3 mg / mL was used instead of 50 mL of sodium nitrite solution with a concentration of 3 mg / mL to obtain the final product microsphere layered composite metal hydroxide composite material M5 (SiO2@Mg-Al MoO4).

[0131] The specific selection and dosage of raw materials are shown in Table 1;

[0132] Preparation of anti-corrosion and thermal insulation coating S6:

[0133] A1: Mix the additives and water under the following conditions: stirring speed of 600 r / min and stirring time of 15 min;

[0134] A2: Add the microsphere layered composite metal hydroxide material, epoxy resin and functional pigment to the mixture in step A1 and mix them. The mixing conditions include: stirring speed of 300 r / min and stirring time of 10 min.

[0135] Example 7

[0136] Preparation of microbead layered composite metal hydroxide composite material M6:

[0137] The microsphere layered composite metal hydroxide composite material M6 was prepared according to Example 1, except that in step (3), the pH value of the solution was adjusted to 10, and 50 mL of sodium phosphate solution with a concentration of 5 mg / mL was used instead of 50 mL of sodium nitrite solution with a concentration of 3 mg / mL to obtain the final product microsphere layered composite metal hydroxide composite material M6 (SiO2@Mg-AlPO4).

[0138] The specific selection and dosage of raw materials are shown in Table 1;

[0139] Preparation of anti-corrosion and thermal insulation coating S7:

[0140] A1: Mix the additives and water under the following conditions: stirring speed of 700 r / min and stirring time of 30 min;

[0141] A2: Add the microsphere layered composite metal hydroxide composite material, epoxy resin and functional pigment to the mixture in step A1 and mix them. The mixing conditions include: stirring speed of 400 r / min and stirring time of 20 min.

[0142] Example 8

[0143] The specific selection and dosage of raw materials are shown in Table 1;

[0144] Preparation of anti-corrosion and thermal insulation coating S8:

[0145] A1: Mix the additives and water under the following conditions: stirring speed of 800 r / min and stirring time of 10 min;

[0146] A2: Add the microsphere layered composite metal hydroxide material, epoxy resin and functional pigment to the mixture in step A1 and mix them. The mixing conditions include: stirring speed of 500 r / min and stirring time of 60 min.

[0147] Example 9

[0148] Preparation of microbead layered composite metal hydroxide material M7:

[0149] The microbead layered composite metal hydroxide composite material M7 was prepared according to the method of Example 1. The difference is that in step (3), the pH value of the solution was adjusted to 8 to obtain the final product microbead layered composite metal hydroxide composite material M7 (SiO2@Mg-Al NO2).

[0150] The specific selection and dosage of raw materials are shown in Table 1;

[0151] Preparation of anti-corrosion and thermal insulation coating S9:

[0152] A1: Mix the additives and water under the following conditions: stirring speed of 500 r / min and stirring time of 20 min;

[0153] A2: Add the microsphere layered composite metal hydroxide material, epoxy resin and functional pigment to the mixture in step A1 and mix them. The mixing conditions include: stirring speed of 200 r / min and stirring time of 50 min.

[0154] Example 10

[0155] Preparation of microbead layered composite metal hydroxide composite material M8:

[0156] The microbead layered composite metal hydroxide composite material M8 was prepared according to Example 1. The difference is that in step (1), the pH value of the mixture was adjusted to 10, nickel nitrate hexahydrate was used instead of magnesium nitrate hexahydrate, and ferric nitrate nonahydrate was used instead of aluminum nitrate nonahydrate. In step (3), the pH value of the solution was adjusted to 10 to obtain the final product ceramic microbead Mg-Al layered composite metal hydroxide composite material M8 (SiO2@Ni-Fe NO2).

[0157] The specific selection and dosage of raw materials are shown in Table 1;

[0158] Preparation of anti-corrosion and thermal insulation coating S10:

[0159] A1: Mix the additives and water under the following conditions: stirring speed of 600 r / min and stirring time of 30 min;

[0160] A2: Add the microsphere layered composite metal hydroxide material, epoxy resin and functional pigment to the mixture in step A1 and mix them. The mixing conditions include: stirring speed of 300 r / min and stirring time of 30 min.

[0161] Comparative Example 1

[0162] Preparation of anti-corrosion and thermal insulation coating S11:

[0163] The implementation was carried out in accordance with Example 1, except that the raw materials did not contain the microbead layered composite metal hydroxide composite material M1.

[0164] Comparative Example 2

[0165] Preparation of anti-corrosion and thermal insulation coating S12:

[0166] The implementation was carried out in accordance with Example 1, except that ceramic microspheres were used instead of the microsphere layered composite metal hydroxide composite material M1 with the same weight.

[0167] Comparative Example 3

[0168] Preparation of anti-corrosion and thermal insulation coating S13:

[0169] The implementation was carried out in accordance with Example 1, except that the same weight of Mg-Al layered composite metal hydroxide was used instead of the microbead layered composite metal hydroxide composite material M1.

[0170] Test case

[0171] (1) The coatings prepared in Example 1 and Comparative Example 1 were coated on a 20# steel sheet measuring 5cm × 2.5cm × 0.2cm and cured at 30°C for 48 hours. Then, the sheet was immersed in a 5wt% sodium chloride solution for a neutral salt spray test. Figure 1 This is a graph showing the test results of a neutral salt spray test conducted on a 5cm × 2.5cm × 0.2cm 20# steel sheet using the coating prepared in Example 1. Figure 2 The image shows the test results of a neutral salt spray test conducted on a 5cm × 2.5cm × 0.2cm 20# steel sheet using the coating prepared in Comparative Example 1. Figure 1 (a) is a graph showing the test results after soaking for 100 hours. Figure 1 (b) is a graph showing the test results after soaking for 300 hours. Figure 1 (c) is a graph showing the test results after soaking for 1000 hours; Figure 2 (a) is a graph showing the test results after soaking for 100 hours. Figure 2 (b) is a graph showing the test results after soaking for 300 hours. Figure 2 (c) is a graph showing the test results after soaking for 1000 hours;

[0172] Depend on Figure 1 and Figure 2 It can be seen that the coating prepared by adding microbead layered composite metal hydroxide in Example 1 has better anti-corrosion performance on metals than the coating prepared by not adding microbead layered composite metal hydroxide in Comparative Example 1.

[0173] (2) The anti-corrosion performance of the coatings prepared in Examples 1-10 and Comparative Examples 1-3 was tested. The test method was as follows: the sample to be tested was coated on a Q235 carbon steel electrode with a diameter of 1 cm × 1 cm × 0.5 cm, cured at 30°C for 48 h, and then immersed in a sodium chloride solution with a concentration of 3.5 wt%. The electrochemical impedance at the artificial defects was characterized. The test results are shown in Table 2. Figure 3 The image shows the electrochemical impedance spectroscopy results at the artificial defects on a 1cm × 1cm × 0.5cm Q235 carbon steel electrode after the coating prepared in Example 1 was applied. Figure 3 (a) shows the electrochemical impedance spectroscopy results at the artificial defect on the Q235 carbon steel electrode after soaking for 2 hours. Figure 3(b) shows the electrochemical impedance spectroscopy results at the artificial defect on the Q235 carbon steel electrode after immersion for 12 hours. Figure 3 (c) shows the electrochemical impedance test results at the artificial defect of the Q235 carbon steel electrode after soaking for 24 hours.

[0174] Depend on Figure 3 (a) It can be seen that the minimum impedance at the artificial defect after soaking for 2 hours is 2.15 × 10⁻⁶. 5 Ω; by Figure 3 (b) It can be seen that the minimum resistance value after soaking for 12 hours is 2.29 × 10⁻⁶. 5 Ω; by Figure 3 (c) It can be seen that the minimum resistance value after soaking for 24 hours is 2.38 × 10⁻⁶. 5 Ω; This indicates that as time goes on, the impedance at the artificial defect of the Q235 carbon steel electrode increases, suggesting that the nitrite ions released by the micro-bead layered composite metal hydroxide in the coating can promote the formation of a dense oxide layer on the steel surface and prevent further severe corrosion of the Q235 carbon steel electrode.

[0175] (3) The thermal conductivity of the coatings prepared in Examples 1-10 and Comparative Examples 1-3 was tested. The test method was as follows: the sample to be tested was coated on a Q235 carbon steel electrode with a diameter of 1 cm × 1 cm × 0.5 cm and cured at 30°C for 48 h. Then it was immersed in a sodium chloride solution with a concentration of 3.5 wt% for 24 h. After drying, the thermal conductivity of the coating was tested using a thermal conductivity meter. The test results are shown in Table 2.

[0176] Table 2

[0177]

[0178]

[0179] As can be seen from the results in Table 2, the coatings prepared by the anti-corrosion and heat-insulating coatings of the present invention have good heat-insulating and anti-corrosion properties. In particular, the coatings prepared by the coatings prepared in Examples 1-3 have even better heat insulation and anti-corrosion functions.

[0180] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A corrosion-resistant and thermal insulation coating composition, characterized in that, The anti-corrosion and thermal insulation coating composition contains a microsphere layered composite metal hydroxide composite material, epoxy resin and curing agent, wherein the microsphere layered composite metal hydroxide composite material includes microspheres and layered composite metal hydroxides coated on the surface of the microspheres; The microspheres are glass microspheres and / or ceramic microspheres; The interlayer anions of the layered composite metal hydroxide are corrosion-inhibiting anions, and these corrosion-inhibiting anions are selected from MoO4. 2- PO4 3- HCOO - CH3(CH2) 11 OSO3 - NO3 - and NO2 - One or more of the following; The preparation method of the microsphere layered composite metal hydroxide material includes the following steps: (1) Mix microbeads, metal precursor, solvent and substances that can form carbonate ions in solution to obtain a mixture, adjust the pH of the mixture to >7, and then carry out the reaction; (2) Perform solid-liquid separation and heat treatment on the material obtained in step (1); (3) Mix the material obtained by heat treatment in step (2) with a solution containing corrosion inhibitory compound, adjust the pH value of the solution to >7, and then carry out the reaction.

2. The anti-corrosion and thermal insulation coating composition according to claim 1, characterized in that, The weight ratio of the epoxy resin to the curing agent is 1:0.3-0.

5.

3. The anti-corrosion and thermal insulation coating composition according to claim 1 or 2, characterized in that, The weight ratio of the epoxy resin and the microsphere layered composite metal hydroxide is 1:0.01-0.

2.

4. The anti-corrosion and thermal insulation coating composition according to claim 3, characterized in that, The epoxy resin is a water-based epoxy resin.

5. The anti-corrosion and thermal insulation coating composition according to any one of claims 1-2 and 4, characterized in that, The curing agent is a water-based epoxy curing agent and / or an organosilicon-modified curing agent.

6. The anti-corrosion and thermal insulation coating composition according to any one of claims 1-2 and 4, characterized in that, The microspheres have a particle size of 0.1-500 μm.

7. The anti-corrosion and thermal insulation coating composition according to claim 6, characterized in that, The microspheres have a particle size of 50-150 μm.

8. The anti-corrosion and thermal insulation coating composition according to any one of claims 1-2, 4 and 7, characterized in that, The metal elements in the layered composite metal hydroxide are metal M and metal N; The metal M is selected from one or more of Mg, Ni, Cu, Zn and Ca, and the metal N is selected from one or more of Al, Co, Fe, Cr and Ga.

9. The anti-corrosion and thermal insulation coating composition according to claim 8, characterized in that, The metal precursor is a metal M precursor and a metal N precursor; The molar ratio of the metal M precursor to the metal N precursor is 1:0.2-5, calculated as metals.

10. The anti-corrosion and thermal insulation coating composition according to claim 8 or 9, characterized in that, The weight ratio of the microspheres to the metal M precursor is 1:0.5-5.

11. The anti-corrosion and thermal insulation coating composition according to any one of claims 1-2 and 9, characterized in that, The anti-corrosion and heat-insulating coating composition also contains functional pigments.

12. The anti-corrosion and thermal insulation coating composition according to claim 11, characterized in that, The weight ratio of the epoxy resin to the functional pigment is 1:0.1-0.

3.

13. The anti-corrosion and thermal insulation coating composition according to claim 12, characterized in that, The functional pigments are selected from one or more of titanium dioxide, calcium carbonate, barium sulfate, talc, bentonite, and quartz powder.

14. The anti-corrosion and thermal insulation coating composition according to any one of claims 1-2 or 11, characterized in that, The anti-corrosion and thermal insulation coating composition also contains additives.

15. The anti-corrosion and thermal insulation coating composition according to claim 14, characterized in that, The weight ratio of the epoxy resin to the additive is 1:0.05-0.

1.

16. The anti-corrosion and thermal insulation coating composition according to claim 15, characterized in that, The additives are selected from one or more of the following: dispersants, defoamers, thickeners, and fungicides.

17. A corrosion-resistant and heat-insulating coating, characterized in that, The anti-corrosion and thermal insulation coating is obtained by mixing the anti-corrosion and thermal insulation coating composition according to any one of claims 1-16 with water.

18. The anti-corrosion and thermal insulation coating according to claim 17, characterized in that, The weight ratio of epoxy resin to water is 1:0.3-0.

5.

19. A method for preparing an anti-corrosion and heat-insulating coating, characterized in that, The anti-corrosion and thermal insulation coating is obtained by applying the anti-corrosion and thermal insulation coating of claim 17 or 18 to the surface of the substrate and then curing it.

20. The method according to claim 19, characterized in that, The curing conditions include a temperature of 30-60℃ and a time of 24-60h.

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