Water-based paint anti-flash-rust agent and preparation method and application thereof

Abstract

The invention discloses a water-based paint anti-flash-rust agent and a preparation method and application thereof, and relates to the technical field of preparation of anti-flash-rust agents, the water-based paint anti-flash-rust agent comprises the following components by mass: 40-55% of a corrosion inhibitor; 30%-50% of a solvent; 5%-10% of a dispersant; 2%-5% of a wetting agent; the corrosion inhibitor is n-dodecyl hexaphytate, the solvent is an ethanol aqueous solution, the dispersing agent is polyacrylate, the antirust effect of the water-based paint flash-rust inhibitor is improved, the antirust capacity of the water-based paint flash-rust inhibitor is prolonged, phytic acid and n-dodecanol belong to natural materials, the prepared n-dodecyl hexaphytate is free of pollution to the environment, and the anti-rust effect of the water-based paint flash-rust inhibitor is improved. The paint is nontoxic to human body, safe and environment-friendly.

Description

Technical Field

[0001] The invention relates to the technical field of flash rust prevention agent preparation, and in particular to a water-based paint flash rust prevention agent and a preparation method and application thereof. Background Art

[0002] The flash rust preventer for water-based paint is an anti-rust additive for adding to water-based paint. It is a chemical preparation used to prevent metal surfaces from rusting quickly in a humid environment, especially used in water-based paint or coating processes. Current water-based paint flash rust preventers include a water-based industrial paint high-efficiency flash rust preventer and its application in a Chinese patent application with publication number CN115895318A and a flash rust preventer and its preparation method and application in a Chinese patent application with authorization announcement number CN108192088B.

[0003] Although the corrosion inhibitors in this type of flash rust inhibitor can chelate with metal ions to form stable complexes and inhibit the redox reactions of metal ions, the components in the corrosion inhibitor are not hydrophobic. As a result, after the water-based paint using this type of flash rust inhibitor is applied to the metal surface, the anti-rust effect of the flash rust inhibitor will be greatly weakened when the metal is in a humid environment for a long time. Summary of the invention

[0004] In order to overcome the above-mentioned technical problems, the purpose of the present invention is to provide a water-based paint flash rust inhibitor and a preparation method and application thereof, so as to solve the problem in the prior art that the corrosion inhibitor constituting the flash rust inhibitor is not hydrophobic, and after the water-based paint using this type of flash rust inhibitor is coated on the metal surface, when the metal is in a humid environment for a long time, the anti-rust effect of the flash rust inhibitor will be greatly weakened, resulting in the problem that the metal cannot be rust-proofed for a long time.

[0005] The purpose of the present invention can be achieved through the following technical solutions: The first aspect of the present invention is to provide a water-based paint anti-flash rust agent, the mass percentage of the water-based paint anti-flash rust agent comprises: Corrosion inhibitor, 40%-55%; Solvent, 30%-50%; Dispersant, 5%-10%; Wetting agent, 2%-5%; The corrosion inhibitor is n-dodecyl hexaphytate, the solvent is ethanol aqueous solution, the dispersant is polyacrylate, and the wetting agent is a non-ionic surfactant.

[0006] As a further solution of the present invention: the n-dodecyl hexaphytate is prepared by esterification of phytic acid and n-dodecyl alcohol, and the preparation chemical reaction equation of n-dodecyl hexaphytate is: C6H6(OP(OH)3)6+12C 12 H 21OH→C6H6(OPO3(C 12 H 21 )2)6+12H20.

[0007] As a further embodiment of the present invention: the nonionic surfactant includes polyethylene glycol, polypropylene glycol, coconut glucoside or decyl glucoside.

[0008] As a further solution of the present invention: the molecular structural formula of the n-dodecyl hexaphytate is: .

[0009] The second aspect of the present invention is to provide a method for preparing a water-based paint flash rust inhibitor, comprising the following steps: S1: dissolving phytic acid in anhydrous dichloromethane, and using a reaction flask and a magnetic stirrer to uniformly stir the phytic acid and anhydrous dichloromethane to form a reactant solution; S2: adding dicyclohexylcarbodiimide and N,N-dimethylaminopyridine to the reactant solution; S3: Add n-dodecanol to the reaction flask under stirring conditions, maintain the solution temperature at 25°C-40°C, and stir for 24h-48h; S4: filtering the solution in the reaction flask using a filter, and evaporating dichloromethane using a rotary evaporator to obtain a product solution; S5: extracting the product solution using an organic solvent to obtain an extract; S6: drying the extract under reduced pressure to obtain product crystals; S7: adding ethanol aqueous solution into the reaction kettle and heating to 45°C-55°C; S8: adding the product crystals into the heated ethanol aqueous solution and stirring evenly until completely dissolved; S9: adding polyacrylate and nonionic surfactant into the reaction kettle, and continuing to stir to form a mixed solution; S10: Cool the mixed solution to room temperature, and obtain an anti-flash rust agent solution after filtering.

[0010] As a further solution of the present invention: the mass ratio of phytic acid to n-dodecyl alcohol is 1:3.5.

[0011] As a further solution of the present invention: S3 comprises the following steps: S3.1: Add n-dodecyl alcohol to the reaction flask while stirring the reactant solution; S3.2: Maintain the temperature of the solution in the reaction flask at 25°C-40°C; S3.3: After adding n-dodecyl alcohol and stirring for 12 h, add silica to the reaction flask; S3.4: Continue stirring for 12h-36h.

[0012] As a further solution of the present invention: S6 comprises the following steps: S6.1: Place the extract into a vacuum drying oven; S6.2: Control the vacuum degree of the vacuum drying oven between 0.08MPa-0.1MPa; S6.3: Heat the temperature of the vacuum drying oven uniformly to 40°C-50°C within 10min-15min; S6.4: Continue heating until the extract is completely evaporated, leaving product crystals.

[0013] As a further solution of the present invention: S8 comprises the following steps: S8.1: adding corundum to the product crystals to form mixed crystals; S8.2: putting the mixed crystals into a grinder for grinding, and passing through a 100-mesh filter to obtain crystal powder; S8.3: Add the crystalline powder to an ethanol-water solution at 45°C-55°C and stir evenly until completely dissolved; S8.4: Filter the ethanol-water solution through filter paper to remove the corundum.

[0014] The third aspect of the present invention is to provide an application of a water-based paint flash rust preventer in the preparation of a water-based paint, wherein the mass percentage content of the water-based paint flash rust preventer in the water-based paint is 0.03%-0.20%.

[0015] Beneficial effects of the present invention: In the present invention, phytic acid and n-dodecyl alcohol undergo an esterification reaction under the action of a catalyst to generate n-dodecyl hexaphytate. The n-dodecyl hexaphytate, as a flash rust preventer for water-based paint, has an excellent anti-rust effect. Since the n-dodecyl hexaphytate contains an organic phosphoric acid group and a long alkyl group, the organic phosphoric acid group is complexed with a metal ion to form a stable complex, thereby inhibiting the redox reaction of the metal ion. The long alkyl group is hydrophobic and forms a hydrophobic film on the surface of the metal in a humid environment, so that the metal ions cannot contact water molecules, thereby greatly improving the anti-rust effect of the water-based paint flash rust preventer and extending the anti-rust ability of the water-based paint flash rust preventer. Phytic acid and n-dodecyl alcohol are both natural materials. The prepared n-dodecyl hexaphytate is non-polluting to the environment, non-toxic to the human body, safe and environmentally friendly, and very suitable for promotion and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the accompanying drawings: Figure 1 It is a flow chart of the preparation method of the water-based paint flash rust preventer of the present invention; Figure 2 The chemical equation diagram of the esterification reaction of phytic acid and n-dodecyl alcohol of the present invention; Figure 3 Schematic diagram of round iron sheets No. 1 to No. 4 in Examples 1 to 4 of the present invention placed for 28 days; Figure 4 It is a schematic diagram of No. 5 round iron sheet in the comparative example of the present invention being placed for 28 days. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] The ways to obtain the various components in the water-based paint anti-rust agent are: Phytic acid—Jiangsu Caiwei Biotechnology Co., Ltd.; n-Dodecanol (lauryl alcohol)—Jiangsu Bosite Chemical Technology Co., Ltd.; Polyacrylate—Shanghai Hongzhuang Chemical Technology Co., Ltd.; Polyethylene glycol—Zhengzhou Huixi Chemical Products Co., Ltd.; Polypropylene glycol - Jiangsu Hai'an Petrochemical Plant; Coco-glucoside—Jining Tangyi Chemical Co., Ltd. Decyl glucoside—Zhonghe Chemical (Shandong) Co., Ltd.; Dicyclohexylcarbodiimide—Jinan Jumeihui Chemical Co., Ltd. N, N-dimethylaminopyridine—Guangzhou Bailing Biotechnology Co., Ltd.; Dichloromethane—Suzhou Qianan Chemical Raw Materials Co., Ltd.

[0019] The above is only one way to obtain the components and does not represent the best way. Those skilled in the art can select an appropriate way to obtain the components according to the specific components in the actual production of the water-based paint flash rust inhibitor.

[0020] Example 1 like Figure 1 and Figure 2As shown, the present invention discloses a water-based paint flash rust preventer, and the mass percentage of the water-based paint flash rust preventer includes a corrosion inhibitor of 50%; a solvent of 40%; a dispersant of 8%; and a wetting agent of 2%. The corrosion inhibitor is n-dodecyl hexaphytate, the solvent is an ethanol aqueous solution, the dispersant is a polyacrylate, and the wetting agent is a non-ionic surfactant, and the non-ionic surfactant includes polyethylene glycol, polypropylene glycol, coconut oil glucoside or decyl glucoside. In this embodiment, polyethylene glycol is used, and n-dodecyl hexaphytate is prepared by esterification reaction of phytic acid and n-dodecyl alcohol, and the mass ratio of phytic acid to n-dodecyl alcohol is 1:3.5. The preparation chemical reaction equation of n-dodecyl hexaphytate is: C6H6(OP(OH)3)6+12C 12 H 21 OH→C6H6(OPO3(C 12 H 21 )2)6+12H20.

[0021] The molecular structure of n-dodecyl hexaphytate is: .

[0022] According to the above ratio, select the corresponding components and follow the following steps to produce water-based paint flash rust inhibitor: S1: dissolving the prepared phytic acid in anhydrous dichloromethane, and using a reaction flask and a magnetic stirrer to evenly stir the phytic acid and anhydrous dichloromethane to form a reactant solution. It should be noted that the amount of anhydrous dichloromethane is determined according to the amount of phytic acid to ensure that the phytic acid can be completely dissolved in the anhydrous dichloromethane. The specific amount is selected by a person skilled in the art according to the room temperature on site; S2: adding dicyclohexylcarbodiimide and N,N-dimethylaminopyridine to the reactant solution. It should be noted that dicyclohexylcarbodiimide and N,N-dimethylaminopyridine are catalysts for the esterification reaction of phytic acid. The amounts of dicyclohexylcarbodiimide and N,N-dimethylaminopyridine are adaptively selected by those skilled in the art according to the amount of phytic acid. The addition ratio of dicyclohexylcarbodiimide and N,N-dimethylaminopyridine is also adjusted by those skilled in the art according to the reaction rate of phytic acid. S3: under stirring conditions, add n-dodecyl alcohol to the reaction flask, keep the solution temperature at 25°C-40°C, and stir for 24h-48h. It should be noted that n-dodecyl alcohol is also called lauryl alcohol. Lauryl alcohol is named because it was originally extracted from laurel bark. It has the chemical reactivity of higher primary alcohols, is almost non-toxic, and is an environmentally friendly additive with no pollution to the environment. Phytic acid and n-dodecyl alcohol will undergo esterification reaction under the catalysis of dicyclohexylcarbodiimide and N, N-dimethylaminopyridine. The chemical reaction equation is: C6H6(OP(OH)3)6+12C12 H 21 OH→C6H6(OPO3(C 12 H 21 ) 2) 6+12H20; Finally, the product n-dodecyl hexaphytate is generated. n-dodecyl hexaphytate is used as a corrosion inhibitor to produce water-based paint flash rust inhibitors. The organic phosphate groups in n-dodecyl hexaphytate complex with metal ions to form stable complexes, which inhibit the redox reactions of metal ions. The long alkyl groups in n-dodecyl hexaphytate are hydrophobic, and can still ensure the anti-rust effect of metals even in a humid environment, greatly improving the anti-rust effect of water-based paint flash rust inhibitors and prolonging the anti-rust ability of water-based paint flash rust inhibitors.

[0023] The specific process is: S3.1: Add n-dodecyl alcohol to the reaction flask while stirring the reactant solution; S3.2: Maintain the temperature of the solution in the reaction flask at 35°C; S3.3: After adding n-dodecyl alcohol and stirring for 12 hours, add silica to the reaction flask. The silica is mainly used to absorb the water generated during the reaction, reduce the amount of water, ensure that the esterification reaction proceeds toward the formation of n-dodecyl hexaphytate, and increase the yield of n-dodecyl hexaphytate; S3.4: Continue stirring for 24h.

[0024] S4: filtering the solution in the reaction flask using a filter, and evaporating dichloromethane using a rotary evaporator after filtering to obtain a product solution. It should be noted that the specifications of the filter and the rotary evaporator are adaptively selected by those skilled in the art according to the properties of n-dodecyl hexaphytate to ensure that the filter can remove silicon dioxide in n-dodecyl hexaphytate; S5: extracting the product solution using an organic solvent to obtain an extract; S6: drying the extract under reduced pressure to obtain product crystals, specifically: firstly putting the extract into a vacuum drying oven, the specification of which is adaptively selected by a person skilled in the art according to the on-site conditions, controlling the vacuum degree of the vacuum drying oven to 0.08 MPa, and then uniformly heating the temperature of the vacuum drying oven to 45° C. within 15 minutes, and continuing heating until the extract is completely evaporated to dryness, leaving product crystals; S7: adding ethanol aqueous solution into the reaction kettle and heating to 50°C; S8: Add the product crystals to the heated ethanol aqueous solution and stir evenly until completely dissolved, specifically: First, corundum is added to the product crystal to form a mixed crystal, and then the mixed crystal is put into a grinder for grinding and passed through a 100-mesh filter to obtain a crystal powder, and then the crystal powder is added to an ethanol aqueous solution at 50° C. and stirred evenly until completely dissolved, and the ethanol aqueous solution is filtered through filter paper to remove the corundum therein; S9: adding polyacrylate and polyethylene glycol into the reaction kettle, and continuing to stir to form a mixed solution; S10: Cool the mixed solution to room temperature, and obtain an anti-flash rust agent solution after filtering. It should be noted that the prepared anti-flash rust agent solution and water-based paint are prepared in a ratio of 0.10% by mass of the water-based paint anti-flash rust agent in the water-based paint. Then, the water-based paint is applied on a round iron sheet to test its anti-flash rust effect, and the round iron sheet is marked as No. 1.

[0025] Example 2 like Figure 1 and Figure 2 As shown, the present invention discloses a water-based paint flash rust preventer, and the mass percentage of the water-based paint flash rust preventer includes a corrosion inhibitor of 55%; a solvent of 30%; a dispersant of 10%; and a wetting agent of 5%. The corrosion inhibitor is n-dodecyl hexaphytate, the solvent is an ethanol aqueous solution, the dispersant is a polyacrylate, and the wetting agent is a non-ionic surfactant, and the non-ionic surfactant includes polyethylene glycol, polypropylene glycol, coconut oil glucoside or decyl glucoside. In this embodiment, polypropylene glycol is used, and n-dodecyl hexaphytate is prepared by esterification reaction of phytic acid and n-dodecyl alcohol, and the mass ratio of phytic acid to n-dodecyl alcohol is 1:3.5. The preparation chemical reaction equation of n-dodecyl hexaphytate is: C6H6(OP(OH)3)6+12C 12 H 21 OH→C6H6(OPO3(C 12 H 21 )2)6+12H20.

[0026] The molecular structure of n-dodecyl hexaphytate is: .

[0027] According to the above ratio, select the corresponding components and follow the following steps to produce water-based paint flash rust inhibitor: S1: dissolving the prepared phytic acid in anhydrous dichloromethane, and using a reaction flask and a magnetic stirrer to evenly stir the phytic acid and anhydrous dichloromethane to form a reactant solution. It should be noted that the amount of anhydrous dichloromethane is determined according to the amount of phytic acid to ensure that the phytic acid can be completely dissolved in the anhydrous dichloromethane. The specific amount is selected by a person skilled in the art according to the room temperature on site; S2: adding dicyclohexylcarbodiimide and N,N-dimethylaminopyridine to the reactant solution. It should be noted that dicyclohexylcarbodiimide and N,N-dimethylaminopyridine are catalysts for the esterification reaction of phytic acid. The amounts of dicyclohexylcarbodiimide and N,N-dimethylaminopyridine are adaptively selected by those skilled in the art according to the amount of phytic acid. The addition ratio of dicyclohexylcarbodiimide and N,N-dimethylaminopyridine is also adjusted by those skilled in the art according to the reaction rate of phytic acid. S3: under stirring conditions, add n-dodecyl alcohol to the reaction flask, keep the solution temperature at 25°C, and stir for 24 hours. It should be noted that n-dodecyl alcohol is also called lauryl alcohol. Lauryl alcohol is named because it was originally extracted from laurel bark. It has the chemical reactivity of higher primary alcohols, is almost non-toxic, and is an environmentally friendly additive with no pollution to the environment. Phytic acid and n-dodecyl alcohol will undergo esterification reaction under the catalysis of dicyclohexylcarbodiimide and N, N-dimethylaminopyridine. The chemical reaction equation is: C6H6(OP(OH)3)6+12C 12 H 21 OH→C6H6(OPO3(C 12 H 21 ) 2) 6+12H20; Finally, the product n-dodecyl hexaphytate is generated. n-dodecyl hexaphytate is used as a corrosion inhibitor to produce water-based paint flash rust inhibitors. The organic phosphate groups in n-dodecyl hexaphytate complex with metal ions to form stable complexes, which inhibit the redox reactions of metal ions. The long alkyl groups in n-dodecyl hexaphytate are hydrophobic, and can still ensure the anti-rust effect of metals even in a humid environment, greatly improving the anti-rust effect of water-based paint flash rust inhibitors and prolonging the anti-rust ability of water-based paint flash rust inhibitors.

[0028] The specific process is: S3.1: Add n-dodecyl alcohol to the reaction flask while stirring the reactant solution; S3.2: Maintain the temperature of the solution in the reaction flask at 35°C; S3.3: After adding n-dodecyl alcohol and stirring for 12 hours, add silica to the reaction flask. The silica is mainly used to absorb the water generated during the reaction, reduce the amount of water, ensure that the esterification reaction proceeds toward the formation of n-dodecyl hexaphytate, and increase the yield of n-dodecyl hexaphytate; S3.4: Continue stirring for 24h.

[0029] S4: filtering the solution in the reaction flask using a filter, and evaporating dichloromethane using a rotary evaporator after filtering to obtain a product solution. It should be noted that the specifications of the filter and the rotary evaporator are adaptively selected by those skilled in the art according to the properties of n-dodecyl hexaphytate to ensure that the filter can remove silicon dioxide in n-dodecyl hexaphytate; S5: extracting the product solution using an organic solvent to obtain an extract; S6: drying the extract under reduced pressure to obtain product crystals, specifically: firstly putting the extract into a vacuum drying oven, the specification of which is adaptively selected by a person skilled in the art according to the on-site conditions, controlling the vacuum degree of the vacuum drying oven to 0.08 MPa, and then uniformly heating the temperature of the vacuum drying oven to 45° C. within 15 minutes, and continuing heating until the extract is completely evaporated to dryness, leaving product crystals; S7: adding ethanol aqueous solution into the reaction kettle and heating to 50°C; S8: Add the product crystals to the heated ethanol aqueous solution and stir evenly until completely dissolved, specifically: First, corundum is added to the product crystal to form a mixed crystal, and then the mixed crystal is put into a grinder for grinding and passed through a 100-mesh filter to obtain a crystal powder, and then the crystal powder is added to an ethanol aqueous solution at 50° C. and stirred evenly until completely dissolved, and the ethanol aqueous solution is filtered through filter paper to remove the corundum therein; S9: adding polyacrylate and polypropylene glycol into the reaction kettle, and continuing to stir to form a mixed solution; S10: Cool the mixed solution to room temperature, and obtain an anti-flash rust agent solution after filtering. It should be noted that the prepared anti-flash rust agent solution and water-based paint are prepared in a ratio of 0.10% by mass of the water-based paint anti-flash rust agent in the water-based paint. Then, the water-based paint is applied on a round iron sheet to test its anti-flash rust effect. The round iron sheet is marked as No. 2.

[0030] Example 3 like Figure 1 and Figure 2 As shown, the present invention discloses a water-based paint flash rust preventer, and the mass percentage of the water-based paint flash rust preventer includes a corrosion inhibitor of 50%; a solvent of 40%; a dispersant of 8%; and a wetting agent of 2%. The corrosion inhibitor is n-dodecyl hexaphytate, the solvent is an ethanol aqueous solution, the dispersant is a polyacrylate, and the wetting agent is a non-ionic surfactant, and the non-ionic surfactant includes polyethylene glycol, polypropylene glycol, coconut glucoside or decyl glucoside. In this embodiment, coconut glucoside is used, and n-dodecyl hexaphytate is prepared by esterification reaction of phytic acid and n-dodecyl alcohol, and the mass ratio of phytic acid to n-dodecyl alcohol is 1:3.5. The preparation chemical reaction equation of n-dodecyl hexaphytate is: C6H6(OP(OH)3)6+12C 12 H 21 OH→C6H6(OPO3(C 12 H 21 )2)6+12H20.

[0031] The molecular structure of n-dodecyl hexaphytate is: .

[0032] According to the above ratio, select the corresponding components and follow the following steps to produce water-based paint flash rust inhibitor: S1: dissolving the prepared phytic acid in anhydrous dichloromethane, and using a reaction flask and a magnetic stirrer to evenly stir the phytic acid and anhydrous dichloromethane to form a reactant solution. It should be noted that the amount of anhydrous dichloromethane is determined according to the amount of phytic acid to ensure that the phytic acid can be completely dissolved in the anhydrous dichloromethane. The specific amount is selected by a person skilled in the art according to the room temperature on site; S2: adding dicyclohexylcarbodiimide and N,N-dimethylaminopyridine to the reactant solution. It should be noted that dicyclohexylcarbodiimide and N,N-dimethylaminopyridine are catalysts for the esterification reaction of phytic acid. The amounts of dicyclohexylcarbodiimide and N,N-dimethylaminopyridine are adaptively selected by those skilled in the art according to the amount of phytic acid. The addition ratio of dicyclohexylcarbodiimide and N,N-dimethylaminopyridine is also adjusted by those skilled in the art according to the reaction rate of phytic acid. S3: under stirring conditions, add n-dodecyl alcohol to the reaction flask, keep the solution temperature at 30°C, and stir for 36 hours. It should be noted that n-dodecyl alcohol is also called lauryl alcohol. Lauryl alcohol is named because it was originally extracted from laurel bark. It has the chemical reactivity of higher primary alcohols, is almost non-toxic, and is an environmentally friendly additive with no pollution to the environment. Phytic acid and n-dodecyl alcohol will undergo esterification reaction under the catalysis of dicyclohexylcarbodiimide and N, N-dimethylaminopyridine. The chemical reaction equation is: C6H6(OP(OH)3)6+12C 12 H 21 OH→C6H6(OPO3(C 12 H 21 ) 2) 6+12H20; Finally, the product n-dodecyl hexaphytate is generated. n-dodecyl hexaphytate is used as a corrosion inhibitor to produce water-based paint flash rust inhibitors. The organic phosphate groups in n-dodecyl hexaphytate complex with metal ions to form stable complexes, which inhibit the redox reactions of metal ions. The long alkyl groups in n-dodecyl hexaphytate are hydrophobic, and can still ensure the anti-rust effect of metals even in a humid environment, greatly improving the anti-rust effect of water-based paint flash rust inhibitors and prolonging the anti-rust ability of water-based paint flash rust inhibitors.

[0033] The specific process is: S3.1: Add n-dodecyl alcohol to the reaction flask while stirring the reactant solution; S3.2: Maintain the temperature of the solution in the reaction flask at 35°C; S3.3: After adding n-dodecyl alcohol and stirring for 12 hours, add silica to the reaction flask. The silica is mainly used to absorb the water generated during the reaction, reduce the amount of water, ensure that the esterification reaction proceeds toward the formation of n-dodecyl hexaphytate, and increase the yield of n-dodecyl hexaphytate; S3.4: Continue stirring for 24h.

[0034] S4: filtering the solution in the reaction flask using a filter, and evaporating dichloromethane using a rotary evaporator after filtering to obtain a product solution. It should be noted that the specifications of the filter and the rotary evaporator are adaptively selected by those skilled in the art according to the properties of n-dodecyl hexaphytate to ensure that the filter can remove silicon dioxide in n-dodecyl hexaphytate; S5: extracting the product solution using an organic solvent to obtain an extract; S6: drying the extract under reduced pressure to obtain product crystals, specifically: firstly putting the extract into a vacuum drying oven, the specification of which is adaptively selected by a person skilled in the art according to the on-site conditions, controlling the vacuum degree of the vacuum drying oven to 0.08 MPa, and then uniformly heating the temperature of the vacuum drying oven to 45° C. within 15 minutes, and continuing heating until the extract is completely evaporated to dryness, leaving product crystals; S7: adding ethanol aqueous solution into the reaction kettle and heating to 50°C; S8: Add the product crystals to the heated ethanol aqueous solution and stir evenly until completely dissolved, specifically: First, corundum is added to the product crystal to form a mixed crystal, and then the mixed crystal is put into a grinder for grinding and passed through a 100-mesh filter to obtain a crystal powder, and then the crystal powder is added to an ethanol aqueous solution at 50° C. and stirred evenly until completely dissolved, and the ethanol aqueous solution is filtered through filter paper to remove the corundum therein; S9: adding polyacrylic acid salt and coco-glucoside into the reaction kettle, and continuing to stir to form a mixed solution; S10: Cool the mixed solution to room temperature, and obtain an anti-flash rust agent solution after filtering. It should be noted that the prepared anti-flash rust agent solution and water-based paint are prepared in a ratio of 0.10% by mass of the water-based paint anti-flash rust agent in the water-based paint. Then, the water-based paint is applied on a round iron sheet to test its anti-flash rust effect. The round iron sheet is marked as No. 3.

[0035] Example 4 like Figure 1 and Figure 2 As shown, the present invention discloses a water-based paint flash rust preventer, and the mass percentage of the water-based paint flash rust preventer includes a corrosion inhibitor of 40%; a solvent of 50%; a dispersant of 8%; and a wetting agent of 2%. The corrosion inhibitor is n-dodecyl hexaphytate, the solvent is an ethanol aqueous solution, the dispersant is a polyacrylate, and the wetting agent is a non-ionic surfactant, and the non-ionic surfactant includes polyethylene glycol, polypropylene glycol, coconut oil glucoside or decyl glucoside. Decyl glucoside is used in this embodiment, and n-dodecyl hexaphytate is prepared by esterification reaction of phytic acid and n-dodecyl alcohol, and the mass ratio of phytic acid to n-dodecyl alcohol is 1:3.5. The preparation chemical reaction equation of n-dodecyl hexaphytate is: C6H6(OP(OH)3)6+12C 12 H 21 OH→C6H6(OPO3(C 12 H 21 )2)6+12H20.

[0036] The molecular structure of n-dodecyl hexaphytate is: .

[0037] According to the above ratio, select the corresponding components and follow the following steps to produce water-based paint flash rust inhibitor: S1: dissolving the prepared phytic acid in anhydrous dichloromethane, and using a reaction flask and a magnetic stirrer to evenly stir the phytic acid and anhydrous dichloromethane to form a reactant solution. It should be noted that the amount of anhydrous dichloromethane is determined according to the amount of phytic acid to ensure that the phytic acid can be completely dissolved in the anhydrous dichloromethane. The specific amount is selected by a person skilled in the art according to the room temperature on site; S2: adding dicyclohexylcarbodiimide and N,N-dimethylaminopyridine to the reactant solution. It should be noted that dicyclohexylcarbodiimide and N,N-dimethylaminopyridine are catalysts for the esterification reaction of phytic acid. The amounts of dicyclohexylcarbodiimide and N,N-dimethylaminopyridine are adaptively selected by those skilled in the art according to the amount of phytic acid. The addition ratio of dicyclohexylcarbodiimide and N,N-dimethylaminopyridine is also adjusted by those skilled in the art according to the reaction rate of phytic acid. S3: under stirring conditions, add n-dodecyl alcohol to the reaction flask, keep the solution temperature at 40°C, and stir for 48 hours. It should be noted that n-dodecyl alcohol is also called lauryl alcohol. Lauryl alcohol is named because it was originally extracted from laurel bark. It has the chemical reactivity of higher primary alcohols, is almost non-toxic, and is an environmentally friendly additive with no pollution to the environment. Phytic acid and n-dodecyl alcohol will undergo esterification reaction under the catalysis of dicyclohexylcarbodiimide and N, N-dimethylaminopyridine. The chemical reaction equation is: C6H6(OP(OH)3)6+12C 12 H 21 OH→C6H6(OPO3(C 12 H 21 ) 2) 6+12H20; Finally, the product n-dodecyl hexaphytate is generated. n-dodecyl hexaphytate is used as a corrosion inhibitor to produce water-based paint flash rust inhibitors. The organic phosphate groups in n-dodecyl hexaphytate complex with metal ions to form stable complexes, which inhibit the redox reactions of metal ions. The long alkyl groups in n-dodecyl hexaphytate are hydrophobic, and can still ensure the anti-rust effect of metals even in a humid environment, greatly improving the anti-rust effect of water-based paint flash rust inhibitors and prolonging the anti-rust ability of water-based paint flash rust inhibitors.

[0038] The specific process is: S3.1: Add n-dodecyl alcohol to the reaction flask while stirring the reactant solution; S3.2: Maintain the temperature of the solution in the reaction flask at 35°C; S3.3: After adding n-dodecyl alcohol and stirring for 12 hours, add silica to the reaction flask. The silica is mainly used to absorb the water generated during the reaction, reduce the amount of water, ensure that the esterification reaction proceeds toward the formation of n-dodecyl hexaphytate, and increase the yield of n-dodecyl hexaphytate; S3.4: Continue stirring for 24h.

[0039] S4: filtering the solution in the reaction flask using a filter, and evaporating dichloromethane using a rotary evaporator after filtering to obtain a product solution. It should be noted that the specifications of the filter and the rotary evaporator are adaptively selected by those skilled in the art according to the properties of n-dodecyl hexaphytate to ensure that the filter can remove silicon dioxide in n-dodecyl hexaphytate; S5: extracting the product solution using an organic solvent to obtain an extract; S6: drying the extract under reduced pressure to obtain product crystals, specifically: firstly putting the extract into a vacuum drying oven, the specification of which is adaptively selected by a person skilled in the art according to the on-site conditions, controlling the vacuum degree of the vacuum drying oven to 0.08 MPa, and then uniformly heating the temperature of the vacuum drying oven to 45° C. within 15 minutes, and continuing heating until the extract is completely evaporated to dryness, leaving product crystals; S7: adding ethanol aqueous solution into the reaction kettle and heating to 50°C; S8: Add the product crystals to the heated ethanol aqueous solution and stir evenly until completely dissolved, specifically: First, corundum is added to the product crystal to form a mixed crystal, and then the mixed crystal is put into a grinder for grinding and passed through a 100-mesh filter to obtain a crystal powder, and then the crystal powder is added to an ethanol aqueous solution at 50° C. and stirred evenly until completely dissolved, and the ethanol aqueous solution is filtered through filter paper to remove the corundum therein; S9: adding polyacrylic acid salt and decyl glucoside into the reaction kettle, and continuing to stir to form a mixed solution; S10: The mixed solution is cooled to room temperature, and an anti-flash rust agent solution is obtained after filtering. It should be noted that the prepared anti-flash rust agent solution and the water-based paint are prepared in a ratio of 0.10% by mass of the water-based paint anti-flash rust agent in the water-based paint, and then the water-based paint is applied on a round iron sheet to test its anti-flash rust effect, and the round iron sheet is marked as No. 4.

[0040] Comparative Example In the comparative example, the existing water-based paint flash rust inhibitor was used, and the corrosion inhibitor n-dodecyl hexaphytate in Example 1 was replaced by sodium nitrate. Then, the flash rust inhibitor was prepared according to the subsequent steps of Example 1, and the prepared flash rust inhibitor solution was prepared with the water-based paint according to the ratio that the mass percentage of the water-based paint flash rust inhibitor in the water-based paint was 0.10%. Then, the water-based paint was applied on a round iron sheet to test its flash rust prevention effect, and the round iron sheet was marked as No. 5.

[0041] Place the round iron sheets No. 1 to No. 5 in air with a humidity of 80% and observe their changes, and obtain Table 1: Table 1 Round iron sheet placement test table

[0042] Combining the data in Table 1 and Figure 3 and Figure 4 It can be seen that the prepared n-dodecyl hexaphytate is used as a corrosion inhibitor for the flash rust inhibitor. Since n-dodecyl hexaphytate contains organic phosphate groups and long alkyl groups, the organic phosphate groups are complexed with metal ions to form stable complexes, which inhibit the redox reactions of metal ions. The long alkyl groups are hydrophobic and form a hydrophobic film on the surface of the metal in a humid environment, making it impossible for the metal ions to contact water molecules, thereby greatly improving the anti-rust effect of the water-based paint flash rust inhibitor and prolonging the anti-rust ability of the water-based paint flash rust inhibitor.

[0043] It should also be noted that phytic acid and n-dodecyl alcohol are both natural materials. The resulting n-dodecyl hexaphytate is environmentally friendly, non-toxic to the human body, safe and environmentally friendly, and very suitable for promotion and use.

[0044] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A water-based paint flash rust preventer, characterized in that: The components of the water-based paint flash rust preventer by mass percentage include: Corrosion inhibitor, 40%-55%; Solvent, 30%-50%; Dispersant, 5%-10%; Wetting agent, 2%-5%; The corrosion inhibitor is n-dodecyl hexaphytate, the solvent is ethanol aqueous solution, the dispersant is polyacrylate, and the wetting agent is a non-ionic surfactant.

2. The water-based paint flash rust preventer according to claim 1, characterized in that: The n-dodecyl hexaphytate is prepared by esterification of phytic acid and n-dodecyl alcohol. The chemical reaction equation for the preparation of n-dodecyl hexaphytate is: C6H6(OP(OH)3)6+12C 12 H 21 OH→C6H6(OPO3(C 12 H 21 )2)6+12H20。 3. The water-based paint flash rust preventer according to claim 1, characterized in that: The nonionic surfactant includes polyethylene glycol, polypropylene glycol, coconut glucoside or decyl glucoside.

4. The water-based paint flash rust preventer according to claim 1, characterized in that: The molecular structural formula of the n-dodecyl hexaphytate is: 。 5. The method for preparing the water-based paint flash rust preventer according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1: dissolving phytic acid in anhydrous dichloromethane, and using a reaction flask and a magnetic stirrer to uniformly stir the phytic acid and anhydrous dichloromethane to form a reactant solution; S2: adding dicyclohexylcarbodiimide and N,N-dimethylaminopyridine to the reactant solution; S3: Add n-dodecanol to the reaction flask under stirring conditions, maintain the solution temperature at 25°C-40°C, and stir for 24h-48h; S4: filtering the solution in the reaction flask using a filter, and evaporating dichloromethane using a rotary evaporator to obtain a product solution; S5: extracting the product solution using an organic solvent to obtain an extract; S6: drying the extract under reduced pressure to obtain product crystals; S7: adding ethanol aqueous solution into the reaction kettle and heating to 45°C-55°C; S8: adding the product crystals into the heated ethanol aqueous solution and stirring evenly until completely dissolved; S9: adding polyacrylate and nonionic surfactant into the reaction kettle, and continuing to stir to form a mixed solution; S10: Cool the mixed solution to room temperature, and obtain an anti-flash rust agent solution after filtering.

6. The method for preparing the water-based paint flash rust preventer according to claim 5, characterized in that: The mass ratio of the phytic acid to n-dodecanol is 1:3.

5.

7. The method for preparing the water-based paint flash rust preventer according to claim 5, characterized in that: The S3 comprises the following steps: S3.1: Add n-dodecyl alcohol to the reaction flask while stirring the reactant solution; S3.2: Maintain the temperature of the solution in the reaction flask at 25°C-40°C; S3.3: After adding n-dodecyl alcohol and stirring for 12 h, add silica to the reaction flask; S3.4: Continue stirring for 12h-36h.

8. The method for preparing the water-based paint flash rust preventer according to claim 7, characterized in that: The S6 comprises the following steps: S6.1: Place the extract into a vacuum drying oven; S6.2: Control the vacuum degree of the vacuum drying oven between 0.08MPa-0.1MPa; S6.3: Heat the temperature of the vacuum drying oven uniformly to 40°C-50°C within 10min-15min; S6.4: Continue heating until the extract is completely evaporated, leaving product crystals.

9. The method for preparing the water-based paint flash rust preventer according to claim 8, characterized in that: The S8 comprises the following steps: S8.1: adding corundum to the product crystals to form mixed crystals; S8.2: putting the mixed crystals into a grinder for grinding, and passing through a 100-mesh filter to obtain crystal powder; S8.3: Add the crystalline powder to an ethanol-water solution at 45°C-55°C and stir evenly until completely dissolved; S8.4: Filter the ethanol-water solution through filter paper to remove the corundum.

10. Use of the water-based paint flash rust preventer according to any one of claims 1 to 4 in the preparation of water-based paint, characterized in that: The mass percentage content of the water-based paint anti-flash rust agent in the water-based paint is 0.03%-0.20%.

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