Environment-friendly anticorrosive paint and preparation method thereof

Abstract

The invention belongs to the technical field of corrosion prevention, and particularly relates to environment-friendly anticorrosive paint and a preparation method thereof. According to the environment-friendly anticorrosive paint provided by the invention, the corrosion inhibitor loaded by Ce-MOF can play a good barrier effect in the paint, the corrosion inhibitor can be released in time when later corrosion occurs, an active anticorrosive function is achieved, and the corrosion inhibitor can be well dispersed into the paint through L-cysteine modified boron nitride, so that the corrosion resistance of the paint is improved, and the corrosion resistance of the paint is improved. L-cysteine can reduce the rate of metal corrosion and can play a role in protection, boron nitride can play a very good barrier effect, through cooperation of the components, a very good anti-corrosion effect of the paint can be achieved, and the prepared environment-friendly anti-corrosion paint is good in anti-corrosion performance and wide in application.

Description

An environmentally friendly anti-corrosion paint and its preparation method Technical Field

[0001] This invention belongs to the field of corrosion protection technology. More specifically, it relates to an environmentally friendly anti-corrosion paint and its preparation method. Background Technology

[0002] Metals are widely used in industrial production and daily life. They are easily corroded in environments such as air and water, and the mechanisms of corrosion are highly complex. The resulting material changes and structural damage are irreversible, causing serious harm to the environment and the economy. Current main methods of corrosion prevention include corrosion inhibitors, electrochemical corrosion protection, and coating corrosion protection. Among these, coating corrosion protection is widely used due to its advantages such as ease of application and good protective performance.

[0003] L-cysteine ​​molecules possess both a basic amino group and an acidic carboxyl group, acting as corrosion inhibitors to reduce the rate of metal corrosion and form a protective film. L-cysteine ​​can dissociate in solution, producing charged ions. These ions can react chemically with the metal surface to form protective compounds, slowing down metal dissolution. In neutral solutions, L-cysteine ​​molecules primarily bind H+ via the -NH2 group. + Adsorbed on the electrode surface (cathode region of localized corrosion cell), it reduces the cathode reaction rate.

[0004] Boron nitride nanosheets (BNNs) are one or more two-dimensional nanomaterials formed by exfoliating hexagonal boron nitride (h-BN). They are chemically stable and have insulating properties. Introducing them into anti-corrosion coating systems can improve the barrier effect against corrosive media entering the coating. However, their low surface functional groups and high surface energy result in poor dispersibility in paints, which affects their effectiveness.

[0005] Metal-organic frameworks (MOFs) are a new type of nanocontainer with advantages such as high porosity, adjustable pore size, and large specific surface area. They can play a role in corrosion inhibition in the field of corrosion protection.

[0006] CN115926592A discloses an environmentally friendly paint for automotive exterior parts, comprising the following components in parts by weight: 40-60 parts of soybean medium-oil alkyd resin, 20-35 parts of cottonseed oil medium-oil alkyd resin, 26-32 parts of polyurea-modified polyamide polyamine epichlorohydrin, 15-22 parts of organic pigment, 35-54 parts of environmentally friendly high-boiling-point aromatic solvent, 25-30 parts of carbodiimide-modified isocyanate, 0.1-0.3 parts of dispersant, 0.2-0.6 parts of defoamer, and 0.1-0.5 parts of leveling agent. This paint is less prone to fading and loss of gloss, exhibits less yellowing, better color retention, better corrosion resistance, better water resistance and weather resistance, greater performance selectivity, better overall performance, and a wide range of applications, meeting the needs of long-term use.

[0007] CN105713457A discloses an environmentally friendly paint with high corrosion resistance. Its raw materials include modified chlorinated rubber resin, organic fluorinated epoxy resin, acrylic resin, alkyd resin, silicone-acrylic emulsion, 52# chlorinated paraffin, iron oxide red, zinc phosphate, bentonite, antimony trioxide, weathered coal, seaweed powder, zeolite powder, diatomaceous earth, silicates, zirconium oxide, acrylonitrile, ethyl propionate, glycerin, benzoic acid, diacetanilide, preservatives, ammonium polyphosphate, and limonene. The paint of this invention exhibits excellent corrosion resistance and excellent environmental performance.

[0008] Adding corrosion-inhibiting components can improve corrosion resistance, but the corrosion resistance is insufficient, the durability is poor, or the hardness is poor, which cannot meet market demands. Summary of the Invention

[0009] The technical problem this invention aims to solve is to overcome the defects and shortcomings of existing technologies and provide an environmentally friendly anti-corrosion paint and its preparation method. The environmentally friendly anti-corrosion paint provided by this invention utilizes a Ce-MOF-loaded corrosion inhibitor, which effectively acts as a barrier in the paint and releases the inhibitor promptly when corrosion occurs later, thus providing active corrosion protection. L-cysteine-modified boron nitride is well dispersed in the paint, and L-cysteine ​​reduces the rate of metal corrosion while providing protection, while boron nitride provides a good barrier effect. The combination of these components achieves excellent anti-corrosion properties. The environmentally friendly anti-corrosion paint prepared by this invention has good anti-corrosion performance and wide application.

[0010] The purpose of this invention is to provide an environmentally friendly anti-corrosion paint.

[0011] Another objective of this invention is to provide a method for preparing an environmentally friendly anti-corrosion paint.

[0012] The above-mentioned objective of this invention is achieved through the following technical solution:

[0013] An environmentally friendly anti-corrosion paint, comprising the following components by weight:

[0014] 60-100 parts of alkyd resin;

[0015] 10-15 parts of dimethyl sulfide;

[0016] 5-10 parts of diethylene glycol butyl ether;

[0017] 20-30 parts of corrosion inhibitor@Ce-MOF composite material;

[0018] 10-20 parts of L-cysteine-modified boron nitride;

[0019] 1-2 parts leveling agent;

[0020] Dispersant 0.1~0.3 parts;

[0021] Defoamer 0.2~0.4 parts;

[0022] 0.5-1.5 parts of drying agent;

[0023] Preferably, the corrosion inhibitor is 2-mercaptobenzothiazole and aminomercaptothiadiazole, and the molar ratio of 2-mercaptobenzothiazole to aminomercaptothiadiazole is 0.5-1:1-1.5. More preferably, the molar ratio of 2-mercaptobenzothiazole to aminomercaptothiadiazole is 0.8:1.2.

[0024] In a further technical solution of this invention, the preparation method of the corrosion inhibitor@Ce-MOF composite material includes the following steps:

[0025] 2-Methylimidazole, 2-mercaptobenzothiazole and aminomercaptothiadiazole were ultrasonically dispersed in DMF, then cerium salt was added and ultrasonication was continued; then a solvothermal reaction was carried out, cooled to room temperature, filtered, washed and dried to constant weight to obtain the corrosion inhibitor@Ce-MOF composite material.

[0026] Preferably, the molar ratio of 2-methylimidazole, 2-mercaptobenzothiazole, aminomercaptothiadiazole and cerium salt is 2-4:0.5-1:1-1.5:1-3. More preferably, the molar ratio of 2-methylimidazole, 2-mercaptobenzothiazole, aminomercaptothiadiazole and cerium salt is 3:0.8:1.2:2. The cerium salt is one of cerium nitrate, cerium acetate and cerium chloride.

[0027] Preferably, the ultrasonic time is 20-40 min, the solvothermal reaction conditions are 110-130℃ for 8-14 h, and the drying time is 60-80℃; more preferably, the ultrasonic time is 30 min, the solvothermal reaction conditions are 120℃ for 12 h, and the drying time is 70℃.

[0028] In a further embodiment of the present invention, the method for preparing L-cysteine-modified boron nitride includes the following steps:

[0029] Hexagonal boron nitride nanosheets and L-cysteine ​​were added to deionized water, ultrasonically dispersed, and then vigorously stirred at room temperature and under a protective atmosphere. The mixture was then filtered, washed, and vacuum dried to constant weight to obtain L-cysteine-modified boron nitride.

[0030] Preferably, the mass ratio of the hexagonal boron nitride nanosheets to L-cysteine ​​is 1:1~2.

[0031] Preferably, the ultrasonic dispersion time is 10-20 min; the vigorous stirring time is 15-25 h.

[0032] Preferably, the protective atmosphere is nitrogen or argon, and the vacuum drying temperature is 60-80°C, more preferably 70°C.

[0033] The preparation method of the environmentally friendly anti-corrosion paint described above includes the following steps:

[0034] Alkyd resin, dimethyl sulfide, and diethylene glycol butyl ether are stirred and mixed at a speed of 3000-4000 rpm for 5-15 minutes. Then, the remaining raw materials are added, and stirring is continued at a speed of 2500-3500 rpm for 20-40 minutes to obtain an environmentally friendly anti-corrosion paint.

[0035] The present invention has the following beneficial effects:

[0036] This invention provides an environmentally friendly anti-corrosion paint. The Ce-MOF-loaded corrosion inhibitor effectively acts as a barrier in the paint and releases promptly when corrosion occurs later, providing active corrosion protection. L-cysteine-modified boron nitride is well dispersed in the paint, and L-cysteine ​​reduces the rate of metal corrosion while providing protection, while boron nitride provides a good barrier effect. This invention utilizes the interaction between these components to improve the anti-corrosion ability and performance of the paint. The environmentally friendly anti-corrosion paint prepared by this invention has good anti-corrosion performance and wide application. Detailed Implementation

[0037] The present invention will be further illustrated below with reference to specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in this technical field.

[0038] The alkyd resin is JC115 from Shaoguan Derui Chemical Industry Co., Ltd.; the leveling agent is BYK333; the dispersant is Efka-4310; the defoamer is F-2561; and the drying agent is cobalt naphthenate.

[0039] Unless otherwise specified, all reagents and materials used in the following examples are commercially available.

[0040] Example 1

[0041] An environmentally friendly anti-corrosion paint, comprising the following components by weight:

[0042] 100 parts alkyd resin;

[0043] 10 parts of dimethyl sulfide;

[0044] 10 parts of diethylene glycol butyl ether;

[0045] 20 parts of corrosion inhibitor@Ce-MOF composite material;

[0046] 20 parts of L-cysteine-modified boron nitride;

[0047] 1 part leveling agent;

[0048] 0.3 parts dispersant;

[0049] 0.2 parts of defoamer;

[0050] 1.5 parts of drying agent;

[0051] The preparation method of corrosion inhibitor@Ce-MOF composite material includes the following steps:

[0052] 4 mol of 2-methylimidazole, 0.5 mol of 2-mercaptobenzothiazole and 1.5 mol of aminomercaptothiadiazole were ultrasonically dispersed in 280 mL of DMF, and then 3 mol of cerium nitrate was added. The mixture was ultrasonically dispersed for another 40 min. The mixture was then solvothermal reacted at 130 °C for 8 h, cooled to room temperature, filtered, washed and dried at 80 °C to constant weight to obtain the corrosion inhibitor @Ce-MOF composite material.

[0053] The preparation method of L-cysteine-modified boron nitride includes the following steps:

[0054] 10g of hexagonal boron nitride nanosheets and 20g of L-cysteine ​​were added to 200mL of deionized water and ultrasonically dispersed for 20min. Then, the mixture was vigorously stirred for 25h at room temperature and under a nitrogen atmosphere. After filtration and washing, the mixture was vacuum dried at 80℃ to constant weight to obtain L-cysteine-modified boron nitride.

[0055] A method for preparing an environmentally friendly anti-corrosion paint includes the following steps:

[0056] Alkyd resin, dimethyl sulfide, and diethylene glycol butyl ether are stirred and mixed at a speed of 3500 rpm for 10 minutes. Then, the remaining raw materials are added, and stirring is continued at a speed of 3000 rpm for 30 minutes to obtain an environmentally friendly anti-corrosion paint.

[0057] Example 2

[0058] An environmentally friendly anti-corrosion paint, comprising the following components by weight:

[0059] 80 parts of alkyd resin;

[0060] 13 parts of dimethyl sulfide;

[0061] 8 parts of diethylene glycol butyl ether;

[0062] 25 parts of corrosion inhibitor@Ce-MOF composite material;

[0063] 15 parts of L-cysteine-modified boron nitride;

[0064] 1.5 parts leveling agent;

[0065] 0.2 parts dispersant;

[0066] 0.3 parts of defoamer;

[0067] One part of drying agent;

[0068] The preparation method of corrosion inhibitor@Ce-MOF composite material includes the following steps:

[0069] 3 mol of 2-methylimidazole, 0.8 mol of 2-mercaptobenzothiazole and 1.2 mol of aminomercaptothiadiazole were ultrasonically dispersed in 280 mL of DMF, and then 2 mol of cerium acetate was added. The mixture was ultrasonically dispersed for another 30 min. The mixture was then solvothermal reacted at 120 °C for 12 h, cooled to room temperature, filtered, washed and dried at 70 °C to constant weight to obtain the composite material.

[0070] The preparation method of L-cysteine-modified boron nitride includes the following steps:

[0071] 10g of hexagonal boron nitride nanosheets and 1.5g of L-cysteine ​​were added to 200mL of deionized water and ultrasonically dispersed for 15min. Then, the mixture was vigorously stirred for 20h at room temperature and under an argon atmosphere. After filtration and washing, the mixture was vacuum dried at 70℃ to constant weight to obtain L-cysteine-modified boron nitride.

[0072] The preparation method of an environmentally friendly anti-corrosion paint is the same as that of Example 1.

[0073] Example 3

[0074] An environmentally friendly anti-corrosion paint, comprising the following components by weight:

[0075] 60 parts of alkyd resin;

[0076] 15 parts of dimethyl sulfide;

[0077] 5 parts of diethylene glycol butyl ether;

[0078] 30 parts of corrosion inhibitor@Ce-MOF composite material;

[0079] 10 parts of L-cysteine-modified boron nitride;

[0080] 2 parts leveling agent;

[0081] 0.1 parts dispersant;

[0082] 0.4 parts of defoamer;

[0083] 0.5 parts of drying agent;

[0084] The preparation method of corrosion inhibitor@Ce-MOF composite material includes the following steps:

[0085] 2 mol of 2-methylimidazole, 1 mol of 2-mercaptobenzothiazole and 1 mol of aminomercaptothiadiazole were ultrasonically dispersed in 280 mL of DMF, and then 1 mol of cerium chloride was added. The mixture was ultrasonically dispersed for another 20 min. The mixture was then solvothermal reacted at 110 °C for 14 h, cooled to room temperature, filtered, washed and dried at 60 °C to constant weight to obtain the composite material.

[0086] The preparation method of L-cysteine-modified boron nitride includes the following steps:

[0087] 10g of hexagonal boron nitride nanosheets and 10g of L-cysteine ​​were added to 200mL of deionized water and ultrasonically dispersed for 10min. Then, the mixture was vigorously stirred for 15h at room temperature and under a nitrogen atmosphere. After filtration and washing, the mixture was vacuum dried at 60℃ to constant weight to obtain L-cysteine-modified boron nitride.

[0088] The preparation method of an environmentally friendly anti-corrosion paint is the same as that of Example 1.

[0089] Comparative Example 1

[0090] Except for the differences, Comparative Example 1 is exactly the same as Example 2, except that the preparation method of the corrosion inhibitor@Ce-MOF composite material includes the following steps:

[0091] 3 mol of 2-methylimidazole and 2 mol of 2-mercaptobenzothiazole were ultrasonically dispersed in 280 mL of DMF, and then 2 mol of cerium acetate was added. The mixture was ultrasonically dispersed for another 30 min. The mixture was then solvothermal reacted at 120 °C for 12 h. After cooling to room temperature, the mixture was filtered, washed, and dried at 70 °C to constant weight to obtain the composite material.

[0092] Comparative Example 2

[0093] Except for the differences, Comparative Example 2 is exactly the same as Example 2, except that Ce-MOF is used instead of the corrosion inhibitor@Ce-MOF composite material, and the preparation method of the Ce-MOF includes the following steps:

[0094] 3 mol of 2-methylimidazole was ultrasonically dispersed in 280 mL of DMF, then 2 mol of cerium acetate was added, and the mixture was ultrasonicated for another 30 min. The mixture was then solvothermal reacted at 120 °C for 12 h, cooled to room temperature, filtered, washed, and dried at 70 °C to constant weight to obtain Ce-MOF.

[0095] Comparative Example 3

[0096] Except for the differences, Comparative Example 3 is exactly the same as Example 2, except that an equal amount of hexagonal boron nitride nanosheets are used to replace L-cysteine-modified boron nitride.

[0097] Comparative Example 4

[0098] Except for the differences, Comparative Example 4 is exactly the same as Example 2, except that: 40 parts of corrosion inhibitor@Ce-MOF composite material; 0 parts of L-cysteine-modified boron nitride.

[0099] The paints prepared in Examples 1-3 and Comparative Examples 1-4 were subjected to performance tests. The specific test results are shown in Table 1.

[0100] Hardness was tested according to GB / T 1730-2007B method;

[0101] The drying time was tested according to the method of GB / T 1728-1979;

[0102] The salt spray test shall be conducted in accordance with the method of GB / T 1771-2007;

[0103] Resistance to damp heat was tested according to GB / T 1771-2007.

[0104] Table 1

[0105]

[0106] As shown in Table 1, the environmentally friendly anti-corrosion paint prepared by this invention has excellent corrosion resistance. A comparison of Example 2 with Comparative Examples 1-4 shows that by adding Ce-MOF-loaded corrosion inhibitors and L-cysteine-modified boron nitride, the interaction of these components results in the paint prepared by this invention exhibiting excellent anti-corrosion performance, good hardness, and a short surface drying time.

[0107] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. An environmentally friendly anti-corrosion paint, characterized in that: By weight, it includes the following components: 60-100 parts alkyd resin; 10-15 parts dimethyl sulfide; 5-10 parts diethylene glycol butyl ether; Corrosion inhibitor @Ce-MOF composite material 20~30 parts; L-cysteine ​​modified boron nitride 10~20 parts; leveling agent 1~2 parts; dispersant 0.1~0.3 parts; defoamer 0.2~0.4 parts; drying agent 0.5~1.5 parts.

2. The environmentally friendly anti-corrosion paint according to claim 1, characterized in that: The corrosion inhibitor is 2-mercaptobenzothiazole and aminomercaptothiadiazole, and the molar ratio of 2-mercaptobenzothiazole and aminomercaptothiadiazole is 0.5-1:1-1.

5.

3. The environmentally friendly anti-corrosion paint according to claim 1, characterized in that: The preparation method of the corrosion inhibitor @Ce-MOF composite material includes the following steps: ultrasonically dispersing 2-methylimidazole, 2-mercaptobenzothiazole and aminomercaptothiadiazole into DMF, then adding cerium salt and continuing ultrasonication; then carrying out a solvothermal reaction, cooling to room temperature, filtering, washing, and drying to constant weight to obtain the corrosion inhibitor @Ce-MOF composite material.

4. The environmentally friendly anti-corrosion paint according to claim 3, characterized in that: The molar ratio of the 2-methylimidazolium, 2-mercaptobenzothiazole, aminomercaptothiadiazole and cerium salt is 2-4:0.5-1:1-1.5:1-3; the cerium salt is one of cerium nitrate, cerium acetate, and cerium chloride.

5. The environmentally friendly anti-corrosion paint according to claim 3, characterized in that: The ultrasonic time is 20-40 min, the solvothermal reaction conditions are 110-130℃ for 8-14 h, and the drying time is 60-80℃.

6. The environmentally friendly anti-corrosion paint according to claim 1, characterized in that: The preparation method of L-cysteine-modified boron nitride includes the following steps: adding hexagonal boron nitride nanosheets and L-cysteine ​​to deionized water, ultrasonically dispersing, then vigorously stirring at room temperature and under a protective atmosphere, filtering, washing, and vacuum drying to constant weight to obtain L-cysteine-modified boron nitride.

7. The environmentally friendly anti-corrosion paint according to claim 6, characterized in that: The mass ratio of the hexagonal boron nitride nanosheets to L-cysteine ​​is 1:1~2.

8. The environmentally friendly anti-corrosion paint according to claim 6, characterized in that: The ultrasonic dispersion time is 10-20 min; the vigorous stirring time is 15-25 h.

9. The environmentally friendly anti-corrosion paint according to claim 6, characterized in that: The protective atmosphere is nitrogen or argon, and the vacuum drying temperature is 60-80℃.

10. A method for preparing an environmentally friendly anti-corrosion paint according to any one of claims 1-9, characterized in that: The preparation method includes the following steps: mixing alkyd resin, dimethyl sulfide and diethylene glycol butyl ether at a stirring speed of 3000~4000 rpm for 5~15 min, then adding the remaining raw materials and continuing to stir at a speed of 2500~3500 rpm for 20~40 min to obtain environmentally friendly anti-corrosion paint.

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