Waterproof and anticorrosive two-component cyanogen setting composite coating and preparation method thereof

Abstract

The invention belongs to the technical field of coatings, and particularly relates to a waterproof and anticorrosive two-component cyanogen setting composite coating and a preparation method thereof. Comprising the following steps: preparing anti-corrosion functional alcohol ether; a dynamic hydrophobic migration microsphere filler; carrying out hydrophilic modification on isocyanate; and blending prepolymers. In the preparation process of preparing the dynamic hydrophobic migration microspheres and then adding the waterproof and anticorrosive bi-component cyanogen setting composite coating, the composite coating has stable dispersity and can form a uniform phase, and in the process of heating and curing after coating, hydrophobic components can be released to migrate to the surface of the coating, so that the waterproof and anticorrosive bi-component cyanogen setting composite coating is formed. Therefore, a hydrophobic layer is formed on the surface, the waterproof performance of the coating after film formation is improved, substances in the inner layer can react better, and the adhesive force of the coating is enhanced.

Description

Technical Field

[0001] The present invention belongs to the technical field of coatings, and particularly relates to a two-component cyanate ester composite coating with waterproof and anticorrosive properties and a preparation method thereof. Background Art

[0002] The cyanate ester prepolymer is a high molecular prepolymer with cyanate ester and isocyanate as reaction groups, having excellent chemical corrosion resistance, high adhesion and low temperature curing characteristics, and is widely used in the coating field. The traditional cyanate ester coating forms a polyurethane network through the stepwise addition polymerization of isocyanate and polyol. Although the cured coating has certain waterproof and anticorrosive properties, with the extensive application, higher requirements are put forward for the performance of the cyanate ester coating.

[0003] In order to prevent moisture in the air from penetrating into building materials, the existing cyanate ester coatings often add hydrophobic modified materials such as talcum powder to the coating, so as to provide better waterproof performance for building materials when the coating is formed. However, the hydrophobic modified materials are usually evenly distributed inside the coating forming film layer, and the hydrophobic modified materials cannot be completely distributed on the surface of the substrate, resulting in low material utilization rate, and often affecting the crosslinking density of the polymer during film formation, thus leading to a decrease in the mechanical properties of the film layer after film formation. Summary of the Invention

[0004] In order to solve the above technical defects, the present invention has developed a preparation method of a two-component cyanate ester composite coating with waterproof and anticorrosive properties. By preparing an anticorrosive functionalized alcohol ether and prepolymerizing it with toluene diisocyanate, and then blending it with a dynamic hydrophobic migration microsphere filler and a hydrophilic TDI curing agent, a cyanate ester composite coating with high stability, high adhesion and high tensile strength is prepared, and it has excellent waterproof and anticorrosive properties.

[0005] A preparation method of a two-component cyanate ester composite coating with waterproof and anticorrosive properties includes the following steps: S1: Preparation of anticorrosive functionalized alcohol ether Pentaerythritol, cholesteryl chloride and pyridine are mixed and subjected to a high-temperature reaction. After removing impurities and dehydrating, a mono-armed substituted pentaerythritol ether is obtained. Then it is subjected to a high-temperature reaction with triphenyl thiophosphate, anhydrous potassium carbonate and potassium iodide, and a modified substituted alcohol ether is obtained after extraction. Then it is modified with 2-chloromethyl benzimidazole to obtain an anticorrosive functionalized alcohol ether; S2: Dynamic hydrophobic migration microsphere filler N-vinyl pyrrolidone and itaconic acid are mixed and reacted to obtain a carboxyl-functionalized copolymer, and then reacted with octadecylamine to obtain a migration promoter. Cardanol glycidyl ether and liquid paraffin are melted together, and the migration promoter and nano-cerium oxide are added. After high-speed shearing, it is encapsulated with sodium alginate and CaCl 2 to obtain a dynamic hydrophobic migration microsphere filler; S3: Hydrophilic Modification of Isocyanate and Blending of Prepolymers Toluene diisocyanate and 3 - cyclohexylaminopropylsulfonic acid are dehydrated and then heated for condensation reflux reaction to obtain a hydrophilic TDI curing agent. Then, an anticorrosive functionalized alcohol ether and toluene diisocyanate are co - heated for prepolymerization to obtain a prepolymer dispersion. Then, a dynamic hydrophobic migration microsphere filler, a film - forming agent, and the hydrophilic TDI curing agent are mixed evenly, filtered, and packaged to obtain a waterproof and anticorrosive two - component cyanogel composite coating.

[0006] Further, the preparation of the anticorrosive functionalized alcohol ether in step S1 includes the following steps: S1.1: Pentaerythritol and cholesteryl chloride are placed in a high - pressure reactor at a molar ratio of 1:(1 - 1.5), 30 - 35 parts of pyridine are added, and then nitrogen is introduced to displace the air in the high - pressure reactor. The temperature is raised to 40 - 45°C, and the reaction is stirred at a speed of 450 - 500 rpm for 10 - 12 hours. Then, pyridine is recovered by vacuum distillation to obtain a reaction product. The reactant is extracted 3 - 4 times with saturated NaHCO 3 - ethyl acetate solution to obtain an organic phase, and anhydrous MgSO 4 is added and stirred for 1 - 1.5 hours and then filtered to obtain a single - arm substituted pentaerythritol ether; S1.2: Under nitrogen protection, 18 - 20 parts of triphenyl thiophosphate, 6 - 8 parts of anhydrous potassium carbonate, and 0.3 - 0.4 parts of potassium iodide are placed in a container, 160 - 200 parts of anhydrous acetonitrile are added, and the mixture is activated at 50 - 55°C for 25 - 30 minutes. Then, 80 - 100 parts of the single - arm substituted ether are slowly added, the temperature is raised to 60 - 65°C, and the mixture is kept warm for 10 - 12 hours. After filtering to remove salts, extraction is carried out to obtain a modified substituted alcohol ether; S1.3: 10 - 12 parts of the modified substituted alcohol ether and 15 - 20 parts of N, N - dimethylformamide are placed in a container, stirred evenly, and then placed in an environment of 0 - 2°C. 10 - 12 parts of 2 - chloromethylbenzimidazole are slowly added to the container, and then the temperature is raised to 40 - 45°C and kept warm for 8 - 10 hours. The mixture in the container is placed in a dialysis bag and dialyzed with deionized water for 30 - 40 hours, and then freeze - dried to obtain the anticorrosive functionalized alcohol ether.

[0007] Further, the dynamic hydrophobic migration microsphere filler in step S2 includes the following steps: S2.1: 20 - 25 parts of N - vinylpyrrolidone and 6 - 8 parts of itaconic acid are placed in a container, 0.5 - 0.6 wt% of AIBN initiator is added, and the reaction is carried out at 60 - 65°C for 1.5 - 2 hours to obtain a carboxyl - functionalized copolymer. The carboxyl - functionalized copolymer is mixed with 3 - 5 parts of octadecylamine and then added to 40 - 45 parts of N, N - dimethylformamide, and kept warm at 120 - 130°C for 3.5 - 4 hours to obtain a migration promoter; S2.2: Melt and mix 25 - 30 parts of cardanol glycidyl ether and 10 - 15 parts of liquid paraffin at 80 - 85 °C. After adding 4 - 6 parts of migration promoter and stirring evenly, add 5 - 8 parts of nano - cerium oxide and 4 - 5 wt% of Tween - 80. Then place it in a high - speed shearing machine and shear at a speed of 2000 - 2500 rpm for 8 - 10 minutes to obtain a homogeneous emulsion; S2.3: Add the homogeneous emulsion to 100 - 120 parts of sodium alginate solution with a concentration of 1 - 2%. Stir ultrasonically at a frequency of 30 - 35 kHz for 15 - 20 minutes. Then add 60 - 80 parts of CaCl 2 solution, stir at a speed of 300 - 400 rpm for 30 - 35 minutes, let it stand for 10 - 15 minutes, then add 50 - 60 parts of perfluorooctyltriethoxysilane / acetone solution and stir evenly. The mass fraction of perfluorooctyltriethoxysilane is 14 - 16%. Continue to let it stand for 25 - 30 minutes. Finally, centrifuge at a speed of 6000 - 8000 rpm for 18 - 20 minutes, discard the upper liquid, retain the lower - layer microcapsules, and place the microcapsules in an environment of - 40 °C to - 35 °C for freeze - drying for 6 - 8 hours to obtain dynamic hydrophobic migration microsphere fillers.

[0008] Further, the hydrophilic modification of isocyanate and the blending of prepolymers in step S3 include the following steps: S3.1: Add 5 - 6 wt% of activated molecular sieve to toluene diisocyanate, stir evenly, soak for 7 - 8 d, and store it sealed to obtain anhydrous toluene diisocyanate. Place 3 - cyclohexylaminopropanesulfonic acid in a vacuum drying oven and dry it to constant weight. After cooling to room temperature, store it in a dry environment to obtain anhydrous 3 - cyclohexylaminopropanesulfonic acid; S3.2: Mix 10 - 15 parts of anhydrous toluene diisocyanate and 4 - 5 parts of butyl acetate and add them to a container equipped with a stirrer, a condensing device, and a thermometer. Heat it to 80 - 85 °C under a nitrogen - protection atmosphere, then add 0.8 - 1 part of anhydrous 3 - cyclohexylaminopropanesulfonic acid and 0.8 - 1 part of dimethylcyclohexylamine, keep it warm and condense and reflux for 8 - 10 hours, and obtain a hydrophilic TDI curing agent after cooling; S3.3: Place the anticorrosive functionalized alcohol ether in a container equipped with a stirrer, a condensing device, and a thermometer. Heat it to 80 - 85 °C in a nitrogen atmosphere, then add toluene diisocyanate according to the NCO - OH ratio of 1:(0.85 - 0.9), keep it warm and react for 3 - 4 hours. When the temperature is lowered to 35 - 40 °C, add 25 - 30 wt% of acetone, and let it cool naturally to room temperature to obtain a prepolymer dispersion; S3.4: Place the prepolymer dispersion in a dry container, add 4 - 6 wt% of dynamic hydrophobic migration microsphere filler and 3 - 5 wt% of film-forming agent, and then add hydrophilic TDI curing agent according to the content of OH in the prepolymer dispersion with an NCO-OH ratio of 1:(0.9 - 0.92). After stirring evenly, filter, measure and package to obtain a two-component cyanate ester composite coating with waterproof and anticorrosive properties.

[0009] Further, the saturated NaHCO 3 -ethyl acetate solution in step S1.1 has a volume ratio of saturated NaHCO 3 solution to ethyl acetate of 1:(2.5 - 3).

[0010] Further, the extraction method in step S1.2 is supercritical CO 2 extraction.

[0011] Further, the cut-off molecular weight of the dialysis bag in step S1.3 is 1000 - 1200 Da.

[0012] Further, the particle size of nano-ceria in step S2.2 is 30 - 50 nm.

[0013] Further, the film-forming agent in step S3.4 is dodecyl alcohol ester.

[0014] A two-component cyanate ester composite coating with waterproof and anticorrosive properties is prepared by the preparation method of the above-mentioned two-component cyanate ester composite coating with waterproof and anticorrosive properties.

[0015] Beneficial effects are: 1. By preparing dynamic hydrophobic migration microspheres and then adding them to the preparation process of the two-component cyanate ester composite coating with waterproof and anticorrosive properties, the composite coating not only has stable dispersibility and can form a homogeneous phase, but also during the heating and curing process after coating, the hydrophobic components can be released and migrate to the surface of the coating, thus forming a hydrophobic layer on the surface, improving the waterproof performance of the coating after film formation, and enabling the substances in the inner layer to react better, enhancing the adhesion and mechanical properties of the coating.

[0016] 2. By carrying out a substitution reaction of cholesterol chloride on pentaerythritol to obtain a single-arm substituted pentaerythritol ether, and then modifying it successively with triphenyl thiophosphate and 2-chloromethyl benzimidazole to obtain an alcohol ether with anticorrosive function, and through a stepwise addition polymerization reaction with toluene diisocyanate to obtain a polyurethane prepolymer, the resulting coating can provide excellent anticorrosive performance after film formation and can also endow the coating with better stability.

[0017] 3. In the present invention, toluene diisocyanate, 3 - cyclohexylaminopropanesulfonic acid are dehydrated and then heated with dimethylcyclohexylamine for condensation reflux reaction. During this process, dimethylcyclohexylamine acts as a catalyst to accelerate the addition reaction of -NCO and -NH 2 and at the same time neutralize the sulfonic acid group, forming an ion pair with the -SO 3 H group of 3 - cyclohexylaminopropanesulfonic acid, improving water solubility and storage stability. Then, under the action of dimethylcyclohexylamine, -SO 3 H group is introduced. The prepared hydrophilic TDI curing agent has better hydrophilicity and stability, can enhance the stability and dispersibility of the entire composite coating system, and can form a film layer with a large cross - link density and better tensile strength during coating and curing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flowchart of the preparation method of the two - component cyanogel composite coating with waterproof and anticorrosive functions adopted in the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0020] It should be noted that, unless otherwise specified, the parts in the following embodiments are all in weight parts.

[0021] Example 1 A two - component cyanogel composite coating with waterproof and anticorrosive functions and its preparation method, as Figure 1 shown, includes the following steps: S1: Preparation of anticorrosive functionalized alcohol ether S1.1: Pentaerythritol and cholesteryl chloride are placed in a high - pressure reaction kettle in a molar ratio of 1:1, 30 parts of pyridine are added, and then nitrogen is introduced to displace the air in the high - pressure reaction kettle. After that, the temperature is raised to 40 °C, and the reaction is stirred at a speed of 450 rpm for 10 hours. Then, pyridine is recovered by vacuum distillation to obtain the reaction product. The reactant is extracted 3 times with saturated NaHCO 3 -ethyl acetate solution. The volume ratio of saturated NaHCO 3 in the saturated NaHCO 3 -ethyl acetate solution to ethyl acetate is 1:2.5 to obtain the organic phase. Anhydrous MgSO 4 is added and stirred for 1 hour and then filtered to obtain single - arm substituted pentaerythritol ether; S1.2: Under nitrogen protection, place 18 parts of triphenyl thiophosphate, 6 parts of anhydrous potassium carbonate, and 0.3 part of potassium iodide in a container, add 160 parts of anhydrous acetonitrile, activate at 50 °C for 25 minutes, then slowly add 80 parts of monoarm substituted ether, raise the temperature to 60 °C, keep warm for 10 hours, filter to remove the salt, and then carry out supercritical CO 2 extraction at 140 MPa and 45 °C to obtain the modified substituted alcohol ether; S1.3: Take 10 parts of the modified substituted alcohol ether and 15 parts of N,N-dimethylformamide and place them in a container. After stirring evenly, place them in an environment at 0 °C, slowly add 10 parts of 2-chloromethylbenzimidazole to the container, then raise the temperature to 40 °C and keep warm for 8 hours. Place the mixture in the container into a dialysis bag with a cut-off molecular weight of 1000 Da and carry out dialysis with deionized water for 30 hours, and then carry out freeze-drying to obtain the anti-corrosion functionalized alcohol ether.

[0022] S2: Dynamic hydrophobic migration microsphere packing S2.1: Place 20 parts of N-vinylpyrrolidone and 6 parts of itaconic acid in a container, add 0.5 wt% of AIBN initiator, react at 60 °C for 1.5 hours to obtain the carboxyl-functionalized copolymer. After mixing the carboxyl-functionalized copolymer with 3 parts of octadecylamine, add them to 40 parts of N,N-dimethylformamide, and keep warm at 120 °C for 3.5 hours to obtain the migration promoter; S2.2: Melt and mix 25 parts of cardanol glycidyl ether and 10 parts of liquid paraffin at 80 °C, add 4 parts of the migration promoter, stir evenly, then add 5 parts of nano cerium oxide with a particle size of 30 nm and 4 wt% of Tween-80, and then place them in a high-speed shear machine and shear at a speed of 2000 rpm for 8 minutes to obtain a uniform emulsion; S2.3: Add the uniform emulsion to 100 parts of a 1% sodium alginate solution, stir ultrasonically at a frequency of 30 kHz for 15 minutes, then add 60 parts of a 3% CaCl 2 solution, stir at a speed of 300 rpm for 30 minutes, let stand for 10 minutes, then add 50 parts of a perfluorooctyltriethoxysilane / acetone solution and stir evenly, where the mass fraction of perfluorooctyltriethoxysilane is 14%, continue to let stand for 25 minutes, and finally centrifuge at a speed of 6000 rpm for 18 minutes, discard the upper layer liquid and retain the lower layer microcapsules. Place the microcapsules in an environment at -40 °C and freeze-dry for 6 hours to obtain the dynamic hydrophobic migration microsphere packing.

[0023] S3: Hydrophilic modification of isocyanate and blending of prepolymers S3.1: Add 5 wt% of activated molecular sieve to toluene diisocyanate, stir evenly, soak for 7 days, and store in a sealed manner to obtain anhydrous toluene diisocyanate. Place 3-cyclohexylaminopropanesulfonic acid in a vacuum drying oven and dry it to a constant weight. After cooling to room temperature, store it in a dry environment to obtain anhydrous 3-cyclohexylaminopropanesulfonic acid; S3.2: Mix 10 parts of anhydrous toluene diisocyanate and 4 parts of butyl acetate and add them to a container equipped with a stirrer, a condensing device, and a thermometer. Heat to 80 °C under a nitrogen protection atmosphere, then add 0.8 part of anhydrous 3-cyclohexylaminopropanesulfonic acid and 0.8 part of dimethylcyclohexylamine, keep warm and condense and reflux for 8 hours, and obtain a hydrophilic TDI curing agent after cooling; S3.3: Place the anti-corrosion functionalized alcohol ether in a container equipped with a stirrer, a condensing device, and a thermometer. Heat to 80 °C in a nitrogen atmosphere, then add toluene diisocyanate according to the NCO-OH ratio of 1:0.85, keep warm and react for 3 hours, cool to 35 °C, add 25 wt% of acetone, and naturally cool to room temperature to obtain a prepolymer dispersion; S3.4: Place the prepolymer dispersion in a dry container, add 4 wt% of dynamic hydrophobic migration microsphere filler and 3 wt% of dodecyl acetate, then according to the OH content in the prepolymer dispersion, add the hydrophilic TDI curing agent according to the NCO-OH ratio of 1:0.9, stir evenly and then filter, measure and package to obtain a waterproof and anti-corrosion two-component cyanogel composite coating.

[0024] Example 2 A waterproof and anti-corrosion two-component cyanogel composite coating and its preparation method, as Figure 1 shown, including the following steps: S1: Preparation of anti-corrosion functionalized alcohol ether S1.1: Place pentaerythritol and cholesteryl chloride in a high-pressure reaction kettle at a molar ratio of 1:1.5, add 35 parts of pyridine, then introduce nitrogen to displace the air in the high-pressure reaction kettle, heat to 40 °C, stir and react at a speed of 450 rpm for 10 hours, then distill under reduced pressure to recover pyridine to obtain a reaction product. Extract the reactant 3 times with a saturated NaHCO 3 -ethyl acetate solution, and the volume ratio of saturated NaHCO 3 in the saturated NaHCO 3 solution to ethyl acetate is 1:2.5 to obtain an organic phase. Add anhydrous MgSO 4 and stir for 1 hour, then filter to obtain a single-arm substituted pentaerythritol ether; S1.2: Under nitrogen protection, 20 parts of triphenyl thiophosphate, 8 parts of anhydrous potassium carbonate and 0.4 part of potassium iodide are placed in a container, 200 parts of anhydrous acetonitrile are added, activated at 50 °C for 25 minutes, then 100 parts of mono-arm substituted ether are slowly added, the temperature is raised to 60 °C, and kept warm for 10 hours. After filtering off the salt, supercritical CO 2 extraction is carried out at 140 MPa and 45 °C to obtain modified substituted alcohol ether; S1.3: Take 12 parts of modified substituted alcohol ether and 20 parts of N,N-dimethylformamide and place them in a container. After stirring evenly, place them in an environment of 0 °C. Slowly add 12 parts of 2-chloromethylbenzimidazole to the container, then raise the temperature to 40 °C and keep warm for 8 hours. The mixture in the container is filled into a dialysis bag with a molecular weight cut-off of 1000 Da and dialyzed with deionized water for 30 hours, and then freeze-dried to obtain anti-corrosion functionalized alcohol ether.

[0025] S2: Dynamic hydrophobic migration microsphere packing S2.1: Place 25 parts of N-vinylpyrrolidone and 8 parts of itaconic acid in a container, add 0.6 wt% of AIBN initiator, react at 60 °C for 1.5 hours to obtain carboxyl-functionalized copolymer. After mixing the carboxyl-functionalized copolymer with 5 parts of octadecylamine, add them to 45 parts of N,N-dimethylformamide, and keep warm at 120 °C for 3.5 hours to obtain a migration promoter; S2.2: Melt and mix 30 parts of cardanol glycidyl ether and 15 parts of liquid paraffin at 80 °C, add 6 parts of migration promoter, stir evenly, then add 8 parts of nano-ceria with a particle size of 30 nm and 4 wt% of Tween-80, and then place them in a high-speed shear machine and shear at a speed of 2000 rpm for 8 minutes to obtain a uniform emulsion; S2.3: Add the uniform emulsion to 120 parts of a 1% sodium alginate solution, stir ultrasonically at a frequency of 30 kHz for 15 minutes, then add 80 parts of a 3% CaCl 2 solution, stir at a speed of 300 rpm for 30 minutes, let stand for 10 minutes, then add 60 parts of perfluorooctyltriethoxysilane / acetone solution and stir evenly, where the mass fraction of perfluorooctyltriethoxysilane is 14%, continue to let stand for 25 minutes, and finally centrifuge at a speed of 6000 rpm for 18 minutes, discard the upper layer liquid and retain the lower layer microcapsules. Place the microcapsules in an environment of -40 °C and freeze-dry for 6 hours to obtain dynamic hydrophobic migration microsphere packing.

[0026] S3: Hydrophilic modification of isocyanate and blending of prepolymers S3.1: Add 6 wt% activated molecular sieve to toluene diisocyanate, stir evenly, soak for 7 days, seal and store to obtain anhydrous toluene diisocyanate. Place 3-cyclohexylaminopropanesulfonic acid in a vacuum drying oven and dry it to constant weight. After cooling to room temperature, store it in a dry environment to obtain anhydrous 3-cyclohexylaminopropanesulfonic acid; S3.2: Mix 15 parts of anhydrous toluene diisocyanate and 5 parts of butyl acetate and add them to a container equipped with a stirrer, a condensing device and a thermometer. Heat to 80 °C under a nitrogen protection atmosphere, then add 1 part of anhydrous 3-cyclohexylaminopropanesulfonic acid and 1 part of dimethylcyclohexylamine, keep warm and carry out condensation reflux for 8 hours. After cooling and cooling down, obtain a hydrophilic TDI curing agent; S3.3: Place the anti-corrosion functionalized alcohol ether in a container equipped with a stirrer, a condensing device and a thermometer. Heat up to 80 °C in a nitrogen atmosphere, then add toluene diisocyanate according to the NCO-OH ratio of 1:0.9, keep warm and react for 3 hours. When the temperature is cooled down to 35 °C, add 25 wt% of acetone and naturally cool down to room temperature to obtain a prepolymer dispersion; S3.4: Place the prepolymer dispersion in a dry container, add 6 wt% of dynamic hydrophobic migration microsphere filler and 5 wt% of dodecyl acetate, then according to the OH content in the prepolymer dispersion, add the hydrophilic TDI curing agent according to the NCO-OH ratio of 1:0.92. After stirring evenly, filter, measure and package to obtain a waterproof and anti-corrosion two-component cyanogel composite coating.

[0027] Example 3 A waterproof and anti-corrosion two-component cyanogel composite coating and its preparation method, as Figure 1 shown, including the following steps: S1: Preparation of anti-corrosion functionalized alcohol ether S1.1: Place pentaerythritol and cholesteryl chloride in a molar ratio of 1:1 in a high-pressure reaction kettle, add 30 parts of pyridine, then introduce nitrogen to displace the air in the high-pressure reaction kettle, heat up to 45 °C, stir and react at a speed of 500 rpm for 12 hours, then carry out vacuum distillation to recover pyridine to obtain a reaction product. Extract the reactant 4 times with saturated NaHCO 3 -ethyl acetate solution. The volume ratio of saturated NaHCO 3 in the -ethyl acetate solution to saturated NaHCO 3 solution and ethyl acetate is 1:2.5 to obtain an organic phase. Add anhydrous MgSO 4 and stir for 1.5 hours, then filter to obtain a single-arm substituted pentaerythritol ether; S1.2: Under nitrogen protection, place 18 parts of triphenyl thiophosphate, 6 parts of anhydrous potassium carbonate, and 0.3 part of potassium iodide in a container, add 160 parts of anhydrous acetonitrile, activate at 55 °C for 30 minutes, then slowly add 80 parts of mono-arm substituted ether, raise the temperature to 65 °C, keep warm for 12 hours, filter to remove salts, and then carry out supercritical CO 2 extraction at 150 MPa and 50 °C to obtain modified substituted alcohol ether; S1.3: Take 10 parts of modified substituted alcohol ether and 15 parts of N,N-dimethylformamide and place them in a container. After stirring evenly, place them in an environment at 2 °C, slowly add 10 parts of 2-chloromethylbenzimidazole to the container, then raise the temperature to 45 °C and keep warm for 10 hours. Place the mixture in the container into a dialysis bag with a cut-off molecular weight of 1200 Da and carry out dialysis with deionized water for 40 hours, and then carry out freeze-drying to obtain anti-corrosion functionalized alcohol ether.

[0028] S2: Dynamic hydrophobic migration microsphere packing S2.1: Place 20 parts of N-vinylpyrrolidone and 6 parts of itaconic acid in a container, add 0.5 wt% of AIBN initiator, react at 65 °C for 2 hours to obtain carboxyl-functionalized copolymer. After mixing the carboxyl-functionalized copolymer with 3 parts of octadecylamine, add them to 40 parts of N,N-dimethylformamide and keep warm at 130 °C for 4 hours to obtain a migration promoter; S2.2: Melt and mix 25 parts of cardanol glycidyl ether and 10 parts of liquid paraffin at 85 °C, add 4 parts of migration promoter, stir evenly, then add 5 parts of nano-ceria with a particle size of 50 nm and 5 wt% of Tween-80, and then place them in a high-speed shear machine and shear at a speed of 2000 rpm for 10 minutes to obtain a uniform emulsion; S2.3: Add the uniform emulsion to 100 parts of a 2% sodium alginate solution, stir ultrasonically at a frequency of 35 kHz for 20 minutes, then add 60 parts of a 5% CaCl 2 solution, stir at a speed of 400 rpm for 35 minutes, let stand for 15 minutes, then add 50 parts of perfluorooctyltriethoxysilane / acetone solution and stir evenly, where the mass fraction of perfluorooctyltriethoxysilane is 16%, continue to let stand for 30 minutes, and finally centrifuge at a speed of 8000 rpm for 20 minutes, discard the upper layer liquid and retain the lower layer microcapsules. Place the microcapsules in an environment at -35 °C and carry out freeze-drying for 8 hours to obtain dynamic hydrophobic migration microsphere packing.

[0029] S3: Hydrophilic modification of isocyanate and blending of prepolymers S3.1: Add 5 wt% activated molecular sieve to toluene diisocyanate, stir evenly, soak for 8 days, seal and store to obtain anhydrous toluene diisocyanate. Place 3-cyclohexylaminopropanesulfonic acid in a vacuum drying oven and dry to constant weight. After cooling to room temperature, store it in a dry environment to obtain anhydrous 3-cyclohexylaminopropanesulfonic acid; S3.2: Mix 10 parts of anhydrous toluene diisocyanate and 4 parts of butyl acetate and add them to a container equipped with a stirrer, a condensing device and a thermometer. Heat to 85 °C under a nitrogen protection atmosphere, then add 0.8 part of anhydrous 3-cyclohexylaminopropanesulfonic acid and 0.8 part of dimethylcyclohexylamine, keep warm and carry out condensation reflux for 8 hours. After cooling down, obtain a hydrophilic TDI curing agent; S3.3: Place the anti-corrosion functionalized alcohol ether in a container equipped with a stirrer, a condensing device and a thermometer. Heat up to 85 °C in a nitrogen atmosphere, then add toluene diisocyanate according to the NCO-OH ratio of 1:0.85, keep warm and react for 4 hours. When the temperature is cooled down to 40 °C, add 25 wt% acetone and let it cool naturally to room temperature to obtain a prepolymer dispersion; S3.4: Place the prepolymer dispersion in a dry container, add 4 wt% dynamic hydrophobic migration microsphere filler and 3 wt% dodecyl alcohol ester, then according to the OH content in the prepolymer dispersion, add the hydrophilic TDI curing agent according to the NCO-OH ratio of 1:0.9. After stirring evenly, filter, measure and package to obtain a waterproof and anti-corrosion two-component cyanogel composite coating.

[0030] Comparative Example 1 A preparation method of a waterproof and anti-corrosion two-component cyanogel composite coating, which is different from Example 1 in that Comparative Example 1 removes step S2, replaces the dynamic hydrophobic migration microsphere filler with talc powder of equal mass in step S3.4, and the remaining steps are the same as those in Example 1, to obtain a waterproof and anti-corrosion two-component cyanogel composite coating, denoted as Comparative Example 1.

[0031] Comparative Example 2 A preparation method of a waterproof and anti-corrosion two-component cyanogel composite coating, which is different from Example 1 in that Comparative Example 2 removes step S1, replaces the anti-corrosion functionalized alcohol ether in step S3.3 with poly(ethylene glycol) of equal mass, and the remaining steps are the same as those in Example 1, to obtain a waterproof and anti-corrosion two-component cyanogel composite coating, denoted as Comparative Example 2.

[0032] Comparative Example 3 A preparation method of a waterproof and anti-corrosion two-component cyanogel composite coating, which is different from Example 1 in that Comparative Example 3 replaces the hydrophilic TDI curing agent in step S3.4 with Bayhydur 3100 aqueous isocyanate curing agent of equal mass, and the remaining steps are the same as those in Example 1, to obtain a waterproof and anti-corrosion two-component cyanogel composite coating, denoted as Comparative Example 3.

[0033] Examples 1 - 3 and Comparative Examples 1 - 3 were evenly sprayed on a polytetrafluoroethylene plate with a thickness of 1 mm. After drying at room temperature for 3 days, they were placed in a drying oven at a constant temperature of 45 °C and dried to a constant weight. Then, they were cut into dumbbell-shaped specimen strips of the same size on a punching machine to obtain film samples.

[0034] Mechanical property test: Three film samples of Examples 1 - 3, Comparative Example 1, and Comparative Example 3 were taken respectively to measure the tensile strength and elongation at break on a microcomputer-controlled electronic universal testing machine. The tensile speed was 200 mm / min, and the test results were averaged. Adhesion strength: Referring to GB / T19250 - 2013 "Polyurethane Waterproof Coating", the adhesion strength of the film samples was tested. Three samples were taken for testing respectively, and the test results were averaged. Water resistance test: Water absorption of the outer layer of the film: For the film samples of Examples 1 - 3, Comparative Example 1, and Comparative Example 3, six samples were taken for each. Two inner layers of the same film sample were bonded together, and the bonded film was weighed, and the mass was recorded as m1. Then it was immersed in distilled water, taken out after 48 hours, the surface moisture was blotted dry with absorbent paper, and then the film mass was weighed again, recorded as m2. The water absorption rate was calculated 外 = (m2 - m1) / m1 × 100%, and the calculation results were averaged; Water absorption of the inner layer of the film: For the film samples of Examples 1 - 3, Comparative Example 1, and Comparative Example 3, six samples were taken for each. Two outer layers of the same film sample were bonded together, and the bonded film was weighed, and the mass was recorded as m3. Then it was immersed in distilled water, taken out after 48 hours, the surface moisture was blotted dry with absorbent paper, and then the film mass was weighed again, recorded as m4. The water absorption rate was calculated 内 = (m4 - m3) / m3 × 100%, and the calculation results were averaged. The greater the water absorption rate, the worse the water resistance. The above data were recorded and made into a table, and the results are shown in Table 1.

[0035] Table 1: Properties of the film formed by the two-component cyanate ester composite coating with waterproof and anticorrosive properties

[0036] It can be seen from Table 1 that the tensile strength and elongation at break of Examples 1 - 3 are higher than those of Comparative Example 1 and Comparative Example 3, while the water absorption rates are lower than those of Comparative Example 1 and Comparative Example 3. It can be proved that the dynamic hydrophobic migration microsphere filler can endow the coating with better mechanical properties, adhesion and waterproof properties after film formation. At the same time, it can be proved that the prepared hydrophilic TDI curing agent can better improve the crosslinking density and tensile strength of the film layer. From the water absorption rate in Table 1 外 and water absorption rate 内It can be seen from the data that the water resistance of the outer surfaces of the thin film samples prepared in Examples 1-3 and Comparative Example 3 is higher than that of the inner surfaces. The reason is that the hydrophobic components in the dynamic hydrophobic migration microsphere fillers migrate to the outer surfaces, resulting in a decrease in the hydrophobic performance of the inner surfaces. However, at the same time, the mechanical properties and adhesion of the thin films are improved. The difference between the inner and outer surfaces of the thin film sample prepared in Comparative Example 1 is small because talcum powder is evenly dispersed inside the film layer, but this will affect the mechanical properties and adhesion of the film layer.

[0037] Experiment 2: Corrosion resistance test: Evenly spray Examples 1-3 and Comparative Example 2 on a stainless steel substrate with a thickness of 100 μm. After drying at room temperature for 3 days, place it in a drying oven at a constant temperature of 45 °C and dry until constant weight. Take three samples each and conduct neutral salt spray tests according to GB / T 10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test", record the number of days of rusting, and the observed results are shown in Table 2.

[0038] Table 2: Observation results of corrosion treatment

[0039] It can be seen from the data of Examples 1-3 and Comparative Example 2 in Table 2 that preparing a polyurethane prepolymer by stepwise addition polymerization of a corrosion-resistant functionalized alcohol ether and toluene diisocyanate can provide excellent corrosion resistance after film formation.

[0040] The above examples are only illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Any person familiar with this technology can modify or change the above examples without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present invention should still be covered by the claims of the present invention.

Claims

1. A method for preparing a waterproof and anticorrosive two-component cyanocondensate composite coating, characterized in that: The following steps are involved: S1: Preparation of anticorrosive functionalized alcohol ethers Pentaerythritol, cholesteryl chloride and pyridine are mixed and reacted at high temperature, and then the single-arm substituted pentaerythritol ether is obtained after impurity removal and dehydration, and then the single-arm substituted pentaerythritol ether is reacted with triphenyl thiophosphate, anhydrous potassium carbonate and potassium iodide at high temperature, and then the modified substituted alcohol ether is obtained after extraction, and then the anti-corrosion functionalized alcohol ether is obtained by modification with 2-chloromethylbenzimidazole; S2: Dynamic Hydrophobic Migration Microsphere Packing N-vinyl pyrrolidone and itaconic acid are mixed to obtain a carboxyl functional copolymer, which is then mixed with octadecylamine to obtain a migration promoter, cardanol glycidyl ether and liquid paraffin are co-melted, the migration promoter and nano-cerium oxide are added, and after high-speed shearing, sodium alginate and CaCl2 are used for encapsulation to obtain a dynamic hydrophobic migration microsphere filler; S3: Hydrophilic modification of isocyanate and blending of prepolymers Toluene diisocyanate and 3-cyclohexylaminopropanesulfonic acid are dehydrated and heated for condensation reflux reaction to obtain a hydrophilic TDI curing agent, and then the anti-corrosion functionalized alcohol ether and toluene diisocyanate are co-heated for prepolymerization to obtain a prepolymer dispersion, and then dynamic hydrophobic migration microsphere filler, film-forming agent and hydrophilic TDI curing agent are added and mixed, and filtered and packaged to obtain a waterproof and anti-corrosion two-component cyanocondensate composite coating.

2. The method for preparing a waterproof and anticorrosive two-component cyanide coagulation composite coating according to claim 1, characterized in that: Step S1: Preparation of antiseptic functionalized alcohol ether, comprising the following steps: S1.1: Pentaerythritol and cholesteryl chloride are placed in a high pressure reactor at a molar ratio of 1:(1-1.5), 30-35 parts of pyridine are added, and nitrogen is introduced, the air in the high pressure reactor is replaced, and the temperature is raised to 40-45°C, and the reaction is stirred at a speed of 450-500 rpm for 10-12 hours, and then the pyridine is recovered by vacuum distillation to obtain a reaction product, and the reactant is extracted 3-4 times with a saturated NaHCO3-ethyl acetate solution to obtain an organic phase, anhydrous MgSO4 is added, stirred for 1-1.5 hours, and then filtered to obtain a single-arm substituted pentaerythritol ether; S1.2: Under nitrogen protection, 18-20 parts of triphenyl thiophosphate, 6-8 parts of anhydrous potassium carbonate and 0.3-0.4 parts of potassium iodide are placed in a container, 160-200 parts of anhydrous acetonitrile are added, activated at 50-55°C for 25-30 minutes, then 80-100 parts of single-arm substituted ether are slowly added, the temperature is raised to 60-65°C, and the temperature is kept for 10-12 hours. After filtering to remove salt, supercritical CO2 extraction is performed to obtain a modified substituted alcohol ether; S1.3: Take 10-12 parts of modified substituted alcohol ether and 15-20 parts of N, N-dimethylformamide and put them in a container. After stirring evenly, place it in an environment of 0-2°C. Slowly add 10-12 parts of 2-chloromethylbenzimidazole into the container, and then raise the temperature to 40-45°C and keep it warm for 8-10 hours. Put the mixture in the container into a dialysis bag and dialyze it with deionized water for 30-40 hours, and then freeze-dry it to obtain a preservative functionalized alcohol ether.

3. The method for preparing a waterproof and anticorrosive two-component cyanide coagulation composite coating according to claim 2, characterized in that: Step S2: Dynamic hydrophobic migration microsphere filler, comprising the following steps: S2.1: 20-25 parts of N-vinyl pyrrolidone and 6-8 parts of itaconic acid are placed in a container, 0.5-0.6wt% of AIBN initiator is added, and the mixture is reacted at 60-65°C for 1.5-2 hours to obtain a carboxyl functional copolymer, the carboxyl functional copolymer is mixed with 3-5 parts of octadecylamine, and then the mixture is added to 40-45 parts of N,N-dimethylformamide, and the mixture is kept at 120-130°C for 3.5-4 hours to obtain a migration promoter; S2.2: 25-30 parts of cardanol glycidyl ether and 10-15 parts of liquid paraffin are melt-mixed at 80-85° C., 4-6 parts of migration promoter are added, stirred evenly, 5-8 parts of nano cerium oxide and 4-5wt% of Tween-80 are added, and then placed in a high-speed shearing machine and sheared at a speed of 2000-2500rpm for 8-10 minutes to obtain a uniform emulsion; S2.3: Add the uniform emulsion to 100-120 parts of 1-2% sodium alginate solution, ultrasonically stir at a frequency of 30-35kHz for 15-20 minutes, then add 60-80 parts of 3-5% CaCl2 solution, stir at a speed of 300-400rpm for 30-35 minutes, let it stand for 10-15 minutes, add 50-60 parts of perfluorooctyl triethoxysilane / acetone solution and stir evenly, wherein the mass fraction of perfluorooctyl triethoxysilane is 14-16%, continue to stand for 25-30 minutes, and finally centrifuge at a speed of 6000-8000rpm for 18-20 minutes, discard the upper layer of liquid and retain the lower layer of microcapsules, and freeze-dry the microcapsules at an environment of minus 40℃-minus 35℃ for 6-8 hours to obtain dynamic hydrophobic migration microsphere filler.

4. The method for preparing a waterproof and anticorrosive two-component cyanide coagulation composite coating according to claim 3, characterized in that: Step S3: hydrophilic modification of isocyanate and blending of prepolymers, comprising the following steps: S3.1: Add 5-6 wt% of activated molecular sieves to toluene diisocyanate, stir evenly and soak for 7-8 days, seal and store to obtain anhydrous toluene diisocyanate, dry 3-cyclohexylaminopropanesulfonic acid in a vacuum drying oven to constant weight, cool to room temperature and store in a dry environment to obtain anhydrous 3-cyclohexylaminopropanesulfonic acid; S3.2: 10-15 parts of anhydrous toluene diisocyanate and 4-5 parts of butyl acetate are mixed and added into a container equipped with a stirrer, a condenser and a thermometer, and heated to 80-85°C under a nitrogen atmosphere, and then 0.8-1 parts of anhydrous 3-cyclohexylaminopropanesulfonic acid and 0.8-1 parts of dimethylcyclohexylamine are added, and the mixture is kept warm and refluxed for 8-10 hours, and then cooled to obtain a hydrophilic TDI curing agent; S3.3: Place the anticorrosive functionalized alcohol ether in a container equipped with a stirrer, a condensing device and a thermometer, heat it to 80-85°C in a nitrogen atmosphere, then add toluene diisocyanate according to an NCO-OH ratio of 1:(0.85-0.9), keep the temperature for reaction for 3-4 hours, add 25-30wt% of acetone when the temperature drops to 35-40°C, and naturally cool to room temperature to obtain a prepolymer dispersion; S3.4: Place the prepolymer dispersion in a dry container, add 4-6wt% of dynamic hydrophobic migration microsphere filler and 3-5wt% of film-forming agent, and then add hydrophilic TDI curing agent according to the NCO-OH ratio of 1: (0.9-0.92) based on the OH content in the prepolymer dispersion. After stirring, filter, measure and package to obtain a waterproof and anti-corrosion two-component cyanoacrylate composite coating.

5. The method for preparing a waterproof and anticorrosive two-component cyanide coagulation composite coating according to claim 2, characterized in that: The volume ratio of the saturated NaHCO3 solution to ethyl acetate in the saturated NaHCO3-ethyl acetate solution in step S1.1 is 1:(2.5-3).

6. The method for preparing a waterproof and anticorrosive two-component cyanide coagulation composite coating according to claim 2, characterized in that: The extraction method in step S1.2 is supercritical CO2 extraction.

7. The method for preparing a waterproof and anticorrosive two-component cyanide coagulation composite coating according to claim 2, characterized in that: The molecular weight cut-off of the dialysis bag in step S1.3 is 1000-1200 Da.

8. The method for preparing a waterproof and anticorrosive two-component cyanide coagulation composite coating according to claim 3, characterized in that: The particle size of nano-cerium oxide in step S2.2 is 30-50 nm.

9. The method for preparing a waterproof and anticorrosive two-component cyanide coagulation composite coating according to claim 4, characterized in that: The film-forming agent in step S3.4 is dodecyl alcohol ester.

10. A waterproof and anti-corrosion two-component cyanide-coagulated composite coating, characterized in that: The coating is prepared by the method for preparing a waterproof and anticorrosive two-component cyanide-coating composite coating as described in any one of claims 1 to 9.

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