A waterproof and anticorrosive coating, its preparation method and application

Abstract

The present invention discloses a waterproof and anticorrosive coating, its preparation method and application, relating to the technical field of coatings. It is made from the following raw materials in parts by weight: 30 - 40 parts of carboxyl-terminated hyperbranched polyester resin, 20 - 30 parts of carboxyl-terminated functional polyamide, 10 - 15 parts of hyperbranched polyurethane containing epoxy groups, 15 - 20 parts of filler, 1 - 3 parts of (3,6-diaminoacridin-9-yl)boronic acid, 3 - 5 parts of 1,3,5-triglycidyl-S-triazine trione, 1 - 2 parts of coupling agent, 0.8 - 1.2 parts of leveling agent, 0.6 - 1.3 parts of defoaming agent; the carboxyl-terminated functional polyamide includes structural units introduced by the following monomers: N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone. This coating has excellent waterproof and anticorrosive properties, strong adhesion to the substrate, sufficient solvent resistance and aging resistance, and a long service life.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and particularly relates to a waterproof and anticorrosive coating, a preparation method thereof, and an application thereof. Background Art

[0002] Coatings are important chemical materials and are widely used in fields such as construction, automobiles, machinery, household appliances, light industrial instruments, durable consumer goods, aerospace, and ships. They are essential materials in the national economy. At present, most of the domestic bicycle industry still uses oil-based coatings, which contain a large amount of volatile toxic and harmful organic solvents, and their safety in use and environmental friendliness need to be further improved.

[0003] Compared with traditional oil-based coatings, waterborne coatings such as waterborne acrylic resins have the advantages of being pollution-free, environmentally friendly, and having excellent film-forming properties, and are widely used in fields such as metal corrosion prevention and wood protection; however, waterborne acrylic resin coatings have poor water resistance, poor bonding strength with metal substrates, and the paint film is prone to peeling off in the long-term state, and cannot play a role in protecting and preventing corrosion of metal substrates. It is in this situation that powder coatings emerged. The green environmental protection performance of powder coatings is more prominent and their applicability is stronger. However, powder coatings suitable for waterproof and anticorrosive applications in the bicycle industry are relatively rare, and the existing powder coatings used in the bicycle industry still have more or less technical defects such as limited waterproof and anticorrosive performance, poor adhesion to substrates, insufficient solvent resistance and aging resistance, and short service life.

[0004] In order to solve the above problems, the Chinese invention patent with the authorization announcement number CN111073470B discloses a friction-resistant and non-fading powder coating for bicycles and its application. Its composition components and their weight parts are as follows: polyester resin 63 - 69 parts; TGIC 4.2 - 5.1 parts; filler 14 - 23 parts; rutile titanium dioxide 1 - 10 parts; self-made colorant 2 - 15 parts; auxiliary agent 3.1 - 3.9 parts. The powder coating of this invention has high leveling and high gloss, and at the same time is friction-resistant and non-fading. The coating formed by coating the powder coating on a bicycle has good leveling, high gloss, and at the same time, its wear resistance is greatly improved compared with the coating of ordinary powder coatings, and it does not fade when wiped, and has excellent decorative and protective properties, providing decorative and protective performance for bicycles. However, its waterproof and anticorrosive performance and solvent resistance still need to be further improved.

[0005] It can be seen that it is particularly important to develop a waterproof and anticorrosive coating with good waterproof and anticorrosive performance, strong adhesion to substrates, sufficient solvent resistance and aging resistance, and long service life, as well as its preparation method and application. Summary of the Invention

[0006] The object of the present invention is to provide a waterproof and anti-corrosion coating with excellent waterproof and anti-corrosion performance, strong adhesion to the substrate, sufficient solvent resistance and aging resistance, and a long service life, as well as a preparation method and application thereof, in order to overcome the deficiencies of the prior art.

[0007] To achieve the above object, the technical solution adopted by the present invention is: a waterproof and anti-corrosion coating is made from the following raw materials in parts by weight: 30 - 40 parts of carboxyl-terminated hyperbranched polyester resin, 20 - 30 parts of carboxyl-terminated functional polyamide, 10 - 15 parts of hyperbranched polyurethane containing epoxy groups, 15 - 20 parts of filler, 1 - 3 parts of (3,6-diaminoacridin-9-yl)boronic acid, 3 - 5 parts of 1,3,5-triglycidyl-S-triazine trione, 1 - 2 parts of coupling agent, 0.8 - 1.2 parts of leveling agent, 0.6 - 1.3 parts of defoaming agent; the carboxyl-terminated functional polyamide includes the structural units introduced by the following monomers: N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone.

[0008] Preferably, the carboxyl-terminated hyperbranched polyester resin is carboxyl-terminated hyperbranched polyester resin Hyper C203, provided by Wuhan Hyperbranched Resin Technology Co., Ltd.

[0009] Preferably, the preparation method of the carboxyl-terminated functional polyamide includes the following steps: adding N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, and a catalyst into a high-boiling solvent and mixing evenly to obtain a mixed material, then adding the mixed material into a reaction kettle, replacing the air in the kettle with an inert gas, reacting at 120 - 130 °C under normal pressure for 3 - 5 hours, then raising the temperature to 235 - 255 °C, carrying out polycondensation reaction at 100 - 300 Pa for 18 - 22 hours, adding a chain terminator, continuing to stir and react for 1 - 2 h, then cooling to room temperature, adjusting to normal pressure, precipitating in water, washing the crude product with ethanol 3 - 6 times, and then drying in a vacuum drying oven at 85 - 95 °C to constant weight to obtain the carboxyl-terminated functional polyamide.

[0010] Preferably, the molar ratio of N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, catalyst, high-boiling solvent, and chain terminator is 1:1:(0.8 - 1):(8 - 15):0.1.

[0011] Preferably, the catalyst is at least one of thiophosphonate, phosphorous acid, and thiophosphoramide; the high-boiling solvent is dimethyl sulfoxide; the inert gas is any one of nitrogen, helium, neon, and argon.

[0012] Preferably, the chain terminator is N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid.

[0013] Preferably, there is no special requirement for the source of the hyperbranched polyurethane containing epoxy groups. In one embodiment of the present invention, the hyperbranched polyurethane containing epoxy groups is prepared according to the method of Example 3 of the Chinese invention patent with application announcement number CN105085866A.

[0014] Preferably, the filler is a mixture of high-gloss barium and precipitated barium in a mass ratio of 1:(0.8-1.2).

[0015] Preferably, the particle size of the filler is 1200-2000 mesh.

[0016] Preferably, the coupling agent is at least one of silane coupling agent KH550, silane coupling agent KH560, and silane coupling agent KH570.

[0017] Preferably, the defoaming agent is one or more of tributyl phosphate, defoaming agent Deqian 3100, and defoaming agent BYK088; the leveling agent is at least one of German BYK leveling agent BYK-333 and silicone leveling agent HY-5030.

[0018] Another object of the present invention is to provide a method for preparing a waterproof and anti-corrosion coating, comprising the following steps: mixing the raw materials uniformly by weight, feeding them into a twin-screw extruder for extrusion, crushing them, and then feeding them into a grinder for crushing and grading, separating out fine powder and impurities through a cyclone separator, and separating out the product with a powder sieve having a mesh size of 100-200, and ripening them for 1-3 days to obtain a finished waterproof and anti-corrosion coating.

[0019] Another object of the present invention is to provide an application of the waterproof and anti-corrosion coating in bicycle painting.

[0020] Due to the application of the above technical solution, the present invention has the following beneficial effects:

[0021] (1) The preparation method of the waterproof and anti-corrosion coating disclosed in the present invention has simple process, convenient operation and control, high preparation efficiency and finished product qualification rate, low dependence on equipment, suitable for continuous large-scale production, and has high promotion and application value.

[0022] (2) The waterproof and anticorrosive coating disclosed by the present invention is made from the following raw materials in parts by weight: 30 - 40 parts of carboxyl-terminated hyperbranched polyester resin, 20 - 30 parts of carboxyl-terminated functional polyamide, 10 - 15 parts of hyperbranched polyurethane containing epoxy groups, 15 - 20 parts of filler, 1 - 3 parts of (3,6-diaminoacridin-9-yl)boronic acid, 3 - 5 parts of 1,3,5-triglycidyl-s-triazinetrione, 1 - 2 parts of coupling agent, 0.8 - 1.2 parts of leveling agent, 0.6 - 1.3 parts of defoaming agent; the carboxyl-terminated functional polyamide includes the structural units introduced by the following monomers: N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone. Through the mutual cooperation and joint action of the raw materials, the prepared coating has excellent waterproof and anticorrosive properties, strong adhesion to the substrate, sufficient solvent resistance and aging resistance, and a long service life.

[0023] (3) In the waterproof and anticorrosive coating disclosed by the present invention, the raw materials containing carboxyl groups and boronic acid groups can react chemically with the raw materials containing epoxy groups to cure. At the same time, the raw materials containing amino groups can also react chemically with the raw materials containing epoxy groups. As a result, after the powder coating is cured, the formed coating film molecular structure contains multiple interpenetrating network structures. These interpenetrating network structures cooperate with each other to improve the waterproof and anticorrosive properties of the coating film; through the reasonable selection of the types and dosage ratios of the raw materials, the structures of triazolodiphenylamine, difluorodiphenyl sulfone, acridine, triazinetrione, boronic acid group, hydroxyl group, hyperbranched polyester, amide and hyperbranched polyurethane are simultaneously introduced into the coating film molecular structure. Under the multiple effects of electronic effect, steric effect and conjugate effect of these groups or structures, the prepared coating has better waterproof and anticorrosive properties, stronger adhesion to the substrate, more sufficient solvent resistance and aging resistance, and a longer service life.

[0024] (4) In the waterproof and anticorrosive coating disclosed by the present invention, the carboxyl-terminated functional polyamide includes the structural units introduced by the following monomers: N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone; by simultaneously introducing triazolyl group, difluorodiphenyl sulfone and amide group into the molecular structure of this raw material, it endows excellent film-forming property and aging resistance. After being added to the coating, it can effectively improve the waterproof and anticorrosive properties and solvent resistance in cooperation with other raw material components in the coating. Detailed Embodiments

[0025] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments in the following description are only examples, and those skilled in the art can think of other obvious variations.

[0026] Example 1

[0027] A waterproof and anticorrosive coating is made from the following raw materials in parts by weight: 30 parts of carboxyl-terminated hyperbranched polyester resin, 20 parts of carboxyl-terminated functional polyamide, 10 parts of hyperbranched polyurethane containing epoxy groups, 15 parts of filler, 1 part of (3,6-diaminoacridin-9-yl)boronic acid, 3 parts of 1,3,5-triglycidyl-S-triazine trione, 1 part of coupling agent, 0.8 part of leveling agent, 0.6 part of defoaming agent; the carboxyl-terminated functional polyamide includes structural units introduced by the following monomers: N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone.

[0028] The carboxyl-terminated hyperbranched polyester resin is carboxyl-terminated hyperbranched polyester resin Hyper C203, provided by Wuhan Hyperbranched Resin Technology Co., Ltd.

[0029] The preparation method of the carboxyl-terminated functional polyamide includes the following steps: adding N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, and catalyst into a high-boiling solvent, mixing evenly to obtain a mixed material, then adding the mixed material into a reaction kettle, displacing the air in the kettle with an inert gas, reacting at 120 °C for 3 hours under normal pressure, then heating up to 235 °C, carrying out polycondensation reaction at 100 Pa for 18 hours, adding a chain terminator, continuing to stir and react for 1 h, then cooling to room temperature, adjusting to normal pressure, precipitating in water, washing the crude product 3 times with ethanol, and then drying in a vacuum drying oven at 85 °C to constant weight to obtain the carboxyl-terminated functional polyamide; the molar ratio of N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, catalyst, high-boiling solvent, and chain terminator is 1:1:0.8:8:0.1; the catalyst is thiophosphonate; the high-boiling solvent is dimethyl sulfoxide; the inert gas is nitrogen; the chain terminator is N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid; through GPC test, the M n of the obtained carboxyl-terminated functional polyamide is measured to be 14170 g / mol, and M W / M n = 1.336; through elemental analysis and weight change calculation, the molar ratio of the structural units introduced by N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid and 3,3'-diamino-4,4'-difluorodiphenyl sulfone in the carboxyl-terminated functional polyamide is the same as the theoretical value.

[0030] The hyperbranched polyurethane containing epoxy groups is prepared by the method of Example 3 of the Chinese invention patent with the application publication number of CN105085866A; the filler is composed of high-gloss barium sulfate and precipitated barium sulfate mixed in a mass ratio of 1:0.8; the particle size of the filler is 1200 mesh; the coupling agent is silane coupling agent KH550; the defoaming agent is tributyl phosphate; the leveling agent is BYK leveling agent BYK-333 from BYK of Germany.

[0031] A preparation method of a waterproof and anticorrosive coating comprises the following steps: after mixing each raw material evenly by weight, feeding it into a twin-screw extruder for extrusion, then crushing it, and then feeding it into a grinding machine for pulverization and classification. The over-fine powder and impurities are separated by a cyclone separator, and the product is separated by a powder sieve with 100 meshes, and then aged for 1 day to obtain the finished waterproof and anticorrosive coating.

[0032] Example 2

[0033] A waterproof and anticorrosive coating is made from the following raw materials in parts by weight: 33 parts of carboxyl-terminated hyperbranched polyester resin, 23 parts of carboxyl-terminated functional polyamide, 12 parts of hyperbranched polyurethane containing epoxy groups, 17 parts of filler, 1.5 parts of (3,6-diaminoacridin-9-yl)boronic acid, 3.5 parts of 1,3,5-triglycidyl-s-triazine trione, 1.2 parts of coupling agent, 0.9 part of leveling agent, 0.8 part of defoaming agent; the carboxyl-terminated functional polyamide includes the structural units introduced by the following monomers: N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone.

[0034] The carboxyl-terminated hyperbranched polyester resin is carboxyl-terminated hyperbranched polyester resin Hyper C203 provided by Wuhan Hyperbranched Resin Technology Co., Ltd.

[0035] The preparation method of the carboxyl-terminated functional polyamide comprises the following steps: adding N-(4H-1,2,4-triazole-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone and a catalyst into a high boiling point solvent and mixing them evenly to obtain a mixed material; then adding the mixed material into a reaction kettle, replacing the air in the kettle with an inert gas, reacting at 123°C for 3.5 hours at normal pressure, then heating to 240°C, performing a polycondensation reaction at 150 Pa for 19 hours, then adding a chain terminator, continuing to stir and react for 1.2 hours, then cooling to room temperature, adjusting to normal pressure, and precipitating in water. The crude product is washed with ethanol for 4 times, and then placed in a vacuum drying oven at 87° C. to dry to constant weight to obtain a carboxyl-terminated functional polyamide; the molar ratio of N-(4H-1,2,4-triazole-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, catalyst, high boiling point solvent, and chain terminator is 1:1:0.85:10:0.1; the catalyst is phosphorous acid; the high boiling point solvent is dimethyl sulfoxide; the inert gas is helium; and the chain terminator is N-(4H-1,2,4-triazole-4-yl)diphenylamine-4,4'-dicarboxylic acid.

[0036] The hyperbranched polyurethane containing epoxy groups is made according to the method of Example 3 of the Chinese invention patent with application announcement number CN105085866A; the filler is a mixture of high-gloss barium and precipitated barium in a mass ratio of 1:0.9; the particle size of the filler is 1400 mesh; the coupling agent is silane coupling agent KH560; the defoamer is defoamer Deqian 3100; and the leveling agent is silicone leveling agent HY-5030.

[0037] A preparation method of a waterproof and anti-corrosion coating comprises the following steps: mixing raw materials uniformly by weight, feeding them into a twin-screw extruder for extrusion, crushing them, and finally feeding them into a grinder for pulverization and classification, separating out excessively fine powder and impurities through a cyclone separator, and separating out products through a powder sieve with a 130-mesh powder sieve, and aging them for 1.5 days to obtain a finished waterproof and anti-corrosion coating.

[0038] Example 3

[0039] A waterproof and anticorrosive coating is prepared from the following raw materials in parts by weight: 35 parts of carboxyl-terminated hyperbranched polyester resin, 25 parts of carboxyl-terminated functional polyamide, 13 parts of hyperbranched polyurethane containing epoxy groups, 18 parts of fillers, 2 parts of (3,6-diaminoacridine-9-yl)boric acid, 4 parts of 1,3,5-triglycidyl-S-triazinetrione, 1.5 parts of coupling agent, 1 part of leveling agent, and 0.9 part of defoaming agent; the carboxyl-terminated functional polyamide comprises structural units introduced by the following monomers: N-(4H-1,2,4-triazole-4-yl)diphenylamine-4,4'-dicarboxylic acid and 3,3'-diamino-4,4'-difluorodiphenyl sulfone.

[0040] The carboxyl-terminated hyperbranched polyester resin is carboxyl-terminated hyperbranched polyester resin Hyper C203, provided by Wuhan Hyperbranched Resin Technology Co., Ltd.

[0041] The preparation method of the carboxyl-terminated functional polyamide comprises the following steps: adding N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, and a catalyst into a high-boiling solvent, mixing evenly to obtain a mixed material, then adding the mixed material into a reaction kettle, displacing the air in the kettle with an inert gas, reacting at 125°C for 4 hours under normal pressure, then heating up to 245°C, carrying out polycondensation reaction at 200 Pa for 20 hours, adding a chain terminator, continuously stirring and reacting for 1.5 h, then cooling to room temperature, adjusting to normal pressure, precipitating in water, washing the crude product with ethanol 5 times, and then drying in a vacuum drying oven at 90°C to constant weight to obtain the carboxyl-terminated functional polyamide; the molar ratio of N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, the catalyst, the high-boiling solvent, and the chain terminator is 1:1:0.9:12:0.1; the catalyst is thiophosphoramide; the high-boiling solvent is dimethyl sulfoxide; the inert gas is neon; the chain terminator is N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid.

[0042] The epoxy group-containing hyperbranched polyurethane is prepared by the method of Example 3 of the Chinese invention patent with the application publication number CN105085866A; the filler is composed of high-gloss barium sulfate and precipitated barium sulfate mixed according to a mass ratio of 1:1; the particle size of the filler is 1900 mesh; the coupling agent is silane coupling agent KH570; the defoaming agent is defoaming agent BYK088; the leveling agent is BYK leveling agent BYK-333 of BYK of Germany.

[0043] A preparation method of a waterproof and anticorrosive coating comprises the following steps: mixing each raw material according to parts by weight evenly, feeding into a twin-screw extruder for extrusion, then crushing, then feeding into a grinding machine for pulverizing and grading, separating out fine powders and sundries through a cyclone separator, and separating out the product with a powder sieve, the powder sieve is 150 mesh, and aging for 2 days to obtain the finished waterproof and anticorrosive coating.

[0044] Example 4

[0045] A waterproof and anticorrosive coating is made from the following raw materials in parts by weight: 38 parts of carboxyl-terminated hyperbranched polyester resin, 28 parts of carboxyl-terminated functional polyamide, 14 parts of hyperbranched polyurethane containing epoxy groups, 19 parts of filler, 2.5 parts of (3,6-diaminoacridin-9-yl)boronic acid, 4.5 parts of 1,3,5-triglycidyl-s-triazine trione, 1.8 parts of coupling agent, 1.1 parts of leveling agent, and 1.2 parts of defoaming agent; the carboxyl-terminated functional polyamide includes structural units introduced by the following monomers: N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone.

[0046] The carboxyl-terminated hyperbranched polyester resin is carboxyl-terminated hyperbranched polyester resin Hyper C203, provided by Wuhan Hyperbranched Resin Technology Co., Ltd.

[0047] The preparation method of the carboxyl-terminated functional polyamide includes the following steps: adding N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, and a catalyst into a high-boiling solvent, mixing evenly to obtain a mixed material, then adding the mixed material into a reaction kettle, replacing the air in the kettle with an inert gas, reacting at 128 °C under normal pressure for 4.5 hours, then heating to 250 °C, carrying out polycondensation reaction at 250 Pa for 21 hours, adding a chain terminator, continuing to stir and react for 1.8 h, then cooling to room temperature, adjusting to normal pressure, precipitating in water, washing the crude product with ethanol 6 times, and then drying in a vacuum drying oven at 93 °C to constant weight to obtain the carboxyl-terminated functional polyamide; the molar ratio of N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, the catalyst, the high-boiling solvent, and the chain terminator is 1:1:0.95:14:0.1; the catalyst is a mixture of thiophosphonate, phosphorous acid, and thiophosphoramide in a mass ratio of 1:1:1; the high-boiling solvent is dimethyl sulfoxide; the inert gas is argon; the chain terminator is N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid.

[0048] The epoxy-containing hyperbranched polyurethane is prepared according to the method of Example 3 of the Chinese invention patent with application announcement number CN105085866A; the filler is a mixture of high-gloss barium and precipitated barium in a mass ratio of 1:1.1; the particle size of the filler is 1900 mesh; the coupling agent is a mixture of silane coupling agent KH550, silane coupling agent KH560, and silane coupling agent KH570 in a mass ratio of 1:2:3; the defoamer is a mixture of tributyl phosphate, defoamer Deqian 3100, and defoamer BYK088 in a mass ratio of 1:3:5; the leveling agent is a mixture of German BYK leveling agent BYK-333 and silicone leveling agent HY-5030 in a mass ratio of 1:2.

[0049] A preparation method of a waterproof and anti-corrosion coating comprises the following steps: mixing raw materials uniformly by weight, feeding them into a twin-screw extruder for extrusion, crushing them, and finally feeding them into a grinder for pulverization and classification, separating out excessively fine powder and impurities through a cyclone separator, and separating out products through a powder sieve with a 190-mesh powder sieve, and aging them for 2.5 days to obtain a finished waterproof and anti-corrosion coating.

[0050] Example 5

[0051] A waterproof and anticorrosive coating is prepared from the following raw materials in parts by weight: 40 parts of carboxyl-terminated hyperbranched polyester resin, 30 parts of carboxyl-terminated functional polyamide, 15 parts of hyperbranched polyurethane containing epoxy groups, 20 parts of filler, 3 parts of (3,6-diaminoacridine-9-yl)boric acid, 5 parts of 1,3,5-triglycidyl-S-triazinetrione, 2 parts of coupling agent, 1.2 parts of leveling agent, and 1.3 parts of defoaming agent; the carboxyl-terminated functional polyamide comprises structural units introduced by the following monomers: N-(4H-1,2,4-triazole-4-yl)diphenylamine-4,4'-dicarboxylic acid and 3,3'-diamino-4,4'-difluorodiphenyl sulfone.

[0052] The carboxyl-terminated hyperbranched polyester resin is carboxyl-terminated hyperbranched polyester resin Hyper C203, which is provided by Wuhan Hyperbranched Resin Technology Co., Ltd.

[0053] The preparation method of the terminal carboxyl functional polyamide comprises the following steps: adding N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone and a catalyst into a high-boiling solvent, mixing evenly to obtain a mixed material, then adding the mixed material into a reaction kettle, displacing the air in the kettle with an inert gas, reacting at 130 °C for 5 hours under normal pressure, then heating up to 255 °C, carrying out polycondensation reaction at 300 Pa for 22 hours, adding a chain terminator, continuously stirring and reacting for 2 h, then cooling to room temperature, adjusting to normal pressure, precipitating in water, washing the crude product with ethanol for 6 times, and then drying in a vacuum drying oven at 95 °C to constant weight to obtain the terminal carboxyl functional polyamide; the molar ratio of N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, the catalyst, the high-boiling solvent and the chain terminator is 1:1:1:15:0.1; the catalyst is thiophosphonate; the high-boiling solvent is dimethyl sulfoxide; the inert gas is nitrogen; the chain terminator is N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid.

[0054] The hyperbranched polyurethane containing epoxy groups is prepared by the method of Example 3 of the Chinese invention patent with the application publication number CN105085866A; the filler is composed of high-gloss barium sulfate and precipitated barium sulfate mixed according to a mass ratio of 1:1.2; the particle size of the filler is 2000 mesh; the coupling agent is silane coupling agent KH560; the defoaming agent is tributyl phosphate; the leveling agent is BYK leveling agent BYK-333 of BYK of Germany.

[0055] A preparation method of a waterproof and anticorrosive coating comprises the following steps: mixing each raw material according to parts by weight evenly, feeding into a twin-screw extruder for extrusion, then crushing, and then feeding into a grinding machine for pulverizing and classifying, separating out over-fine powder and sundries through a cyclone separator, and separating out the product with a powder sieve, the powder sieve is 200 mesh, and aging for 3 days to obtain the finished waterproof and anticorrosive coating.

[0056] Comparative Example 1

[0057] A waterproof and anticorrosive coating is basically the same as Example 1, except that an equal amount of terminal carboxyl hyperbranched polyester resin is used to replace the terminal carboxyl functional polyamide, and (3,6-diaminoacridin-9-yl)boronic acid is not added.

[0058] Comparative Example 2

[0059] A waterproof and anticorrosive coating is basically the same as Example 1, except that an equal amount of terephthalic acid is used to replace N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid, and 1,3,5-triglycidyl-S-triazine trione is not added.

[0060] To further illustrate the beneficial technical effects of the waterproof and anticorrosive coatings involved in the embodiments of the present invention, relevant performance tests were carried out on the waterproof and anticorrosive coatings involved in Examples 1-5 and Comparative Examples 1-2. The test methods and test results are shown in Table 1. The curing conditions of each coating during the test were: 200 °C, 10 min. Passing the salt spray resistance test means that the unilateral penetration corrosion width under the film on both sides of the scribe does not exceed 2 mm after 1320 h of the salt spray resistance test, otherwise it fails; passing the artificial aging test means that there are no abnormal phenomena such as powdering, cracking, and peeling after 1000 h of QUV artificial aging, otherwise it fails. The water resistance was tested in accordance with GB / T 1733-1993, and the time when rust spots began to appear on the surface was recorded, with the unit (days). The longer the time, the better the water resistance of the coating.

[0061] Table 1

[0062]

[0063]

[0064] As can be seen from Table 1, the waterproof and anticorrosive coatings involved in the embodiments of the present invention have more excellent solvent resistance, damp heat resistance, artificial aging resistance, salt spray resistance and water resistance than the products of the comparative examples, and have stronger adhesion to the substrate. The use of terminal carboxyl hyperbranched polyester resin, (3,6-diaminoacridin-9-yl)boronic acid, N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid and 1,3,5-triglycidyl-S-triazine trione is beneficial to improving the above properties.

[0065] The above embodiments are only for illustrating the technical concept and characteristics of the present invention, and the purpose is to enable those familiar with this technology to understand the content of the present invention and implement it accordingly. It cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A waterproof and anti-corrosion coating, characterized in that: The invention is prepared from the following raw materials in parts by weight: 30-40 parts of carboxyl-terminated hyperbranched polyester resin, 20-30 parts of carboxyl-terminated functional polyamide, 10-15 parts of epoxy-containing hyperbranched polyurethane, 15-20 parts of filler, 1-3 parts of (3,6-diaminoacridine-9-yl)boric acid, 3-5 parts of 1,3,5-triglycidyl-S-triazinetrione, 1-2 parts of coupling agent, 0.8-1.2 parts of leveling agent and 0.6-1.3 parts of defoaming agent; The preparation method of the carboxyl-terminated functional polyamide comprises the following steps: adding N-(4H-1,2,4-triazole-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone and a catalyst into a high boiling point solvent and mixing them evenly to obtain a mixed material; then adding the mixed material into a reaction kettle, replacing the air in the kettle with an inert gas, reacting at 120-130° C. under normal pressure for 3-5 hours, then heating to 235-255° C., and performing a polycondensation reaction at 100-300 Pa for 18-22 hours. When the reaction mixture is stirred for 1-2 hours, a chain terminator is added, and the reaction mixture is stirred for 1-2 hours. The mixture is then cooled to room temperature, adjusted to normal pressure, and precipitated in water. The crude product is washed with ethanol for 3-6 times, and then dried in a vacuum drying oven at 85-95° C. to constant weight to obtain a carboxyl-terminated functional polyamide. The molar ratio of the N-(4H-1,2,4-triazole-4-yl)diphenylamine-4,4'-dicarboxylic acid, 3,3'-diamino-4,4'-difluorodiphenyl sulfone, catalyst, high boiling point solvent, and chain terminator is 1:1:(0.8-1):(8-15):0.

1.

2. The waterproof and anticorrosive coating according to claim 1, characterized in that: The carboxyl-terminated hyperbranched polyester resin is carboxyl-terminated hyperbranched polyester resin Hyper C203.

3. The waterproof and anticorrosive coating according to claim 1, characterized in that: The catalyst is at least one of thiophosphonate, phosphorous acid, and thiophosphoramide; the high boiling point solvent is dimethyl sulfoxide; and the inert gas is any one of nitrogen, helium, neon, and argon.

4. The waterproof and anticorrosive coating according to claim 1, characterized in that: The chain terminator is N-(4H-1,2,4-triazol-4-yl)diphenylamine-4,4'-dicarboxylic acid.

5. The waterproof and anticorrosive coating according to claim 1, characterized in that: The filler is formed by mixing high-gloss barium and precipitated barium in a mass ratio of 1:(0.8-1.2); the particle size of the filler is 1200-2000 meshes; and the coupling agent is at least one of silane coupling agent KH550, silane coupling agent KH560 and silane coupling agent KH570.

6. The waterproof and anticorrosive coating according to claim 1, characterized in that: The defoaming agent is one or more of tributyl phosphate, defoaming agent Deqian 3100, and defoaming agent BYK088; the leveling agent is at least one of German BYK leveling agent BYK-333 and silicone leveling agent HY-5030.

7. A method for preparing the waterproof and anticorrosive coating according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: mixing the raw materials uniformly according to weight, sending the raw materials into a twin-screw extruder for extrusion, crushing the raw materials, and finally sending the raw materials into a grinder for pulverization and classification, separating the excessively fine powder and impurities through a cyclone separator, and separating the product through a powder sieve with a mesh size of 100-200, and aging the mixture for 1-3 days to obtain a finished waterproof and anticorrosive coating.

8. Use of the waterproof and anti-corrosion coating according to any one of claims 1 to 6 in bicycle painting.

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