High-temperature-resistant building anticorrosive coating and preparation method thereof

Abstract

The application discloses a high-temperature-resistant building anticorrosive coating and a preparation method thereof. The A component is prepared from the following raw materials in parts by weight: carboxyl-modified organic silicon resin 50-60 parts, nano silicon sol 5-15 parts, ceramic microbead 20-30 parts, inert filler 5-10 parts, graphene oxide 0.5-2 parts, and functional additive 5-10 parts. The B component is prepared from the following raw materials in parts by weight: modified polysilazane 30-50 parts and latent curing agent 5-10 parts. In the application, the organic silicon resin is modified by carboxylation. The carboxyl group can react with the amino group (-NH-) in the modified polysilazane in the B component to generate an amide bond, and simultaneously forms a hydrogen bond with the silicon hydroxyl group (-SiOH) in the nano silicon sol, so that the crosslinking point density of the coating is increased by 30%, the water absorption rate is reduced from 1.2% of the ordinary coating to 0.8%, and the penetration of corrosion ions such as Cl ‑ , SO4 2‑ , etc. is effectively inhibited, so that the corrosion resistance of the coating is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of architectural coatings technology, and in particular to a high-temperature resistant architectural anti-corrosion coating and its preparation method. Background Technology

[0002] With the continuous development of modern industry in my country, especially in industries such as metal structure construction, petrochemicals, energy, metallurgy, road and bridge construction, railways, aerospace, and military shipbuilding, there are more and more applications of high-temperature equipment and supporting facilities. However, metal materials are prone to oxidation reactions with oxygen in the air in high-temperature environments, resulting in rust. This causes the metal materials to gradually lose strength and lead to structural defects, becoming a hidden danger for various accidents.

[0003] Commercially available high-temperature resistant building anti-corrosion coatings are mainly divided into two categories: inorganic and organosilicon. Existing organosilicon high-temperature anti-corrosion coatings generally have a heat resistance temperature below 400℃, exhibiting poor anti-corrosion performance. Furthermore, organosilicon itself has poor mechanical properties, low adhesion, abrasion resistance, and solvent resistance, increasingly failing to meet the requirements of modern motors, electrical appliances, aerospace, and applications requiring resistance to special media, making it unsuitable for harsher environments with higher temperatures. Inorganic coatings, on the other hand, have excellent heat resistance, generally withstanding temperatures from 400℃ to 1300℃, with a low film temperature. Their films possess excellent weather resistance, are highly stable under ultraviolet light, exhibit good heat resistance, are non-flammable, have good stain resistance, do not easily absorb dust, maintain a bright decorative effect, produce no volatile organic compounds during manufacturing and use, do not pollute the environment, have abundant raw material resources, and are inexpensive. These advantages have led to their widespread industrial application, and their market prospects and social and economic benefits are very attractive.

[0004] To adapt to the ever-increasing demands of modern production, on the one hand, people are constantly improving the high-temperature resistance and corrosion resistance of inorganic coatings, and on the other hand, they are constantly improving the flexibility of coatings and their adhesion to substrates such as metals and plastics, in order to solve the performance defect of poor adhesion of inorganic coatings and make them adapt to new production needs.

[0005] Chinese invention patent application number 201611162668.1 discloses a graphene-modified inorganic coating and its preparation method, which improves the wear resistance and conductivity of the coating, but its performance in terms of high pressure resistance and adhesion needs to be improved. Summary of the Invention

[0006] To address the problems mentioned in the background section, this invention provides a high-temperature resistant building anti-corrosion coating and its preparation method.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A high-temperature resistant anti-corrosion coating for buildings, comprising component A and component B, wherein component A is made from the following raw materials in parts by weight:

[0009] 50-60 parts of carboxyl-modified silicone resin, 5-15 parts of nano-silica sol, 20-30 parts of ceramic microspheres, 5-10 parts of inert filler, 0.5-2 parts of graphene oxide, and 5-10 parts of functional additives.

[0010] Component B is made from the following raw materials in parts by weight:

[0011] 30-50 parts of modified polysilazane and 5-10 parts of latent curing agent.

[0012] Preferably, the preparation method of the carboxyl-modified organosilicon resin includes the following steps:

[0013] S1. Add diphenyldihydroxysilane, methyldiethoxysilane, and cation exchange resin to a three-necked flask, and purge with nitrogen 3-5 times; heat to 90-95℃, and stir magnetically for 20-24 hours (200-300 rpm). After the reaction is complete, filter while hot to remove the resin. Distill the filtrate under reduced pressure (-0.09 MPa) to remove low-boiling substances, and collect the fraction at 180-200℃ to obtain hydrogen-containing polysiloxane.

[0014] S2. Add allyl malonic acid to the reaction flask, heat to 105-110℃ under nitrogen protection to melt, add chloroplatinic acid-isopropanol solution, and stir for 10-15 minutes until homogeneous.

[0015] S3. Slowly add hydrogen-containing polysiloxane at a rate of 2 g / min. After the addition is complete, keep the temperature at 110℃ for 5 h. Remove unreacted monomers by vacuum distillation at -0.095 MPa and 150℃ to obtain carboxyl-modified organosilicon resin (acid value 30-40 mg KOH / g, number average molecular weight 5000-8000).

[0016] Preferably, the preparation method of the nano-silica sol includes the following steps:

[0017] Add 8-10% mesoporous silica nanoparticles to the basic silica sol and disperse it evenly by ultrasonication. Then, add 3-5% ZIF-8 methanol solution (by weight of the basic silica sol) dropwise and stir continuously at 200-300 r / min for 2-3 h. Next, add 3-5% poly(N-isopropylacrylamide) aqueous solution (by weight of the basic silica sol), stir and mix well. Adjust the pH to 4-5 with hydrochloric acid, raise the temperature to 50-55℃, and react for 2-3 h. After cooling to room temperature, add 0.5-1% photoinitiator (by weight of the basic silica sol) and stir in the dark until completely dissolved. Finally, add 1.5-2% Fe3O4@SiO2 particles (by weight of the basic silica sol) and disperse evenly by ultrasonication.

[0018] Preferably, the molar concentration of the ZIF-8 methanol solution is 0.1-0.3 mol / L;

[0019] The mass fraction of the poly(N-isopropylacrylamide) aqueous solution is 10-15%;

[0020] The photoinitiator is any one of 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and α-hydroxyalkylphenyl ketone.

[0021] Preferably, the ceramic microspheres have a particle size of 50-200 μm, a sphericity >95%, and a high temperature resistance ≥1700℃.

[0022] Preferably, the inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1-1.5.

[0023] Preferably, the functional additive is a mixture of a dispersant and a rheology modifier in a mass ratio of 1:1, wherein the dispersant is polyacrylamide or fatty acid polyethylene glycol ester; and the rheology modifier is any one of fumed silica, bentonite, and hydroxyethyl cellulose.

[0024] Preferably, the method for preparing the modified polysilazane includes the following steps:

[0025] Add polysilazane, tridecafluorooctyltriethoxysilane and hexafluorobutyl methacrylate to the reaction vessel, add xylene to dissolve, heat to 60-65℃ and stir for 25-30 minutes until homogeneous;

[0026] N,N-diethylethanolamine and dibutyltin dilaurate were added, and the mixture was heated to 80-85℃ and reacted under nitrogen protection for 3-4 hours to generate the product. Xylene was removed by vacuum distillation to obtain the modified polysilazane.

[0027] Preferably, the polysilazane comprises 50-70 parts by weight, tridecafluorooctyltriethoxysilane 10-25 parts, hexafluorobutyl methacrylate 8-15 parts, xylene 30-50 parts, N,N-diethylethanolamine 2-5 parts, and dibutyltin dilaurate 0.5-1 parts.

[0028] One molecule of tridecafluorooctyltriethoxysilane can be hydrolyzed and condensed with the Si-H / NH of three polysilazane chains to form a high-density Si-O-Si / Si-N crosslinking network. The ≡Si-OC(O)-C(CH3)=CH2 group introduced by hexafluorobutyl methacrylate through transesterification undergoes free radical crosslinking during coating film formation to form a secondary CC crosslinking network, with the crosslinking density increasing by more than 40% compared to the unmodified system. Meanwhile, long-chain fluoroalkyl groups migrate to the coating surface to form a low surface energy layer, reducing the spreading rate of salt solution on the coating surface and thus delaying the wetting of corrosive media.

[0029] Preferably, the latent curing agent is diaminodiphenyl sulfone.

[0030] A method for preparing a high-temperature resistant anti-corrosion coating for buildings includes the following steps:

[0031] S1. According to the stated weight proportions, add carboxyl-modified organosilicon resin and nano-silica sol to the reactor, stir evenly at 300-500 rpm for 10-15 min, then add ceramic microspheres, graphene oxide and inert filler in sequence for high-speed dispersion at 1000-1500 rpm for 20-30 min.

[0032] S2. Add functional additives, stir for 10-15 minutes until uniformly mixed, and then grind through a sand mill to a fineness of ≤50μm to obtain component A;

[0033] S3. Add the modified polysilazane and latent curing agent to the container, stir at 200-300 rpm for 5-10 minutes until homogeneous to obtain component B.

[0034] S4. Mix component A and component B at a mass ratio of 3-5:1 to obtain a high-temperature resistant building anti-corrosion coating.

[0035] Compared with the prior art, the beneficial effects of the present invention are:

[0036] 1. In this invention, the organosilicon resin is modified by carboxylation. The carboxyl groups can undergo a condensation reaction with the amino groups (-NH-) in the modified polysilazane (component B) to form amide bonds, and simultaneously form hydrogen bonds with the silanol groups (-SiOH) in the nano-silica sol. This increases the crosslinking density of the coating by 30%, reduces the water absorption rate from 1.2% of ordinary coatings to 0.8%, and effectively inhibits Cl-. - SO4 2- Corrosion ions penetrate the coating, thereby significantly improving its corrosion resistance.

[0037] 2. In this invention, by adding nano-silica sol, a multi-level pore structure is formed between mesoporous silica and ZIF-8, increasing the specific surface area from 50 m² / s of ordinary silica sol. 2 / g increased to 200m 2 / g, adsorbs small molecule byproducts (such as water and ethanol) generated during coating curing, reducing coating porosity; Zn in ZIF-8 2+ With Cl - It has strong coordination properties and can capture Cl that has penetrated into the coating. - It delays the corrosion of the substrate.

[0038] Poly(N-isopropylacrylamide) undergoes a low critical solution temperature phase transition at 50°C, changing from a hydrophilic to a hydrophobic state. Upon curing, it forms a core-shell structure: the core of poly(N-isopropylacrylamide) encapsulates Fe3O4@SiO2 magnetic particles, while the outer shell is cross-linked silica sol. This allows the coating to rapidly form a dense film during baking at 80°C, while simultaneously endowing the coating with magnetothermal triggering repairability. Under the influence of an applied alternating magnetic field, the Fe3O4@SiO2 magnetic particles in the coating generate localized heat. This heat can trigger enhanced chain mobility in the thermosensitive poly(N-isopropylacrylamide) and may promote the reorganization of dynamic physical interactions within the coating network. This allows the coating to achieve a certain degree of self-repair at the damaged site, restoring its barrier function. Detailed Implementation

[0039] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] Unless otherwise specified, the raw materials used in this invention are all from commercially available conventional products.

[0041] The basic silica sol was sourced from DuPont (USA), Ludox CL-X;

[0042] Mesoporous silica nanoparticles were purchased from Aladdin, CAS No.: 7631-86-9;

[0043] ZIF-8 was purchased from Aladdin, CAS number: 59061-53-9;

[0044] Fe3O4@SiO2 particles were purchased from Jiangsu Xianfeng Nanomaterials Technology Co., Ltd.

[0045] The graphene oxide was purchased from Henan Wanying Refractory Materials Technology Co., Ltd., model number LG-5901.

[0046] Preparation Example 1

[0047] The preparation method of the carboxyl-modified organosilicon resin includes the following steps:

[0048] S1. Add 50g of diphenyldihydroxysilane, 30g of methyldiethoxysilane, and 5g of cation exchange resin (Amberlyst-15) to a 250mL three-necked flask. Purge the flask with nitrogen three times. Heat the flask to 90℃ and stir magnetically for 24 hours at 300rpm. After the reaction is complete, filter the flask while hot to remove the resin. Distill the filtrate under reduced pressure (-0.09MPa) to remove low-boiling substances. Collect the fraction at 185℃ to obtain hydrogen-containing polysiloxane.

[0049] S2. Add 20g of allyl malonic acid to the reaction flask, heat to 105℃ under nitrogen protection to melt, add 0.5mL of 2wt% chloroplatinic acid-isopropanol solution, and stir for 15min until homogeneous.

[0050] S3. Slowly add 50g of hydrogen-containing polysiloxane at a rate of 2g / min. After the addition is complete, keep the temperature at 110℃ for 5h. Remove unreacted monomers by vacuum distillation at -0.095MPa and 150℃ to obtain carboxyl-modified organosilicon resin with an acid value of 32mgKOH / g and a number-average molecular weight of 5560.

[0051] Preparation Example 2

[0052] The preparation method of the nano-silica sol includes the following steps:

[0053] Add 8g of mesoporous silica nanoparticles to 100g of basic silica sol, and after ultrasonic dispersion, add 3g of ZIF-8 methanol solution with a molar concentration of 0.1mol / L, and stir continuously at 200r / min for 2h. Then add 5g of 10% poly(N-isopropylacrylamide) aqueous solution, stir and mix well, adjust the pH to 4 with hydrochloric acid, heat to 50℃, react for 2h, cool to room temperature, add 1g of 1-hydroxycyclohexylphenyl ketone, stir in the dark until completely dissolved, and finally add 1.5g of Fe3O4@SiO2 particles and ultrasonically disperse evenly.

[0054] Preparation Example 3

[0055] The preparation method of the nano-silica sol includes the following steps:

[0056] Add 9g of mesoporous silica nanoparticles to 100g of basic silica sol, and after ultrasonic dispersion, add 4g of ZIF-8 methanol solution with a molar concentration of 0.2mol / L. Stir continuously at 300r / min for 3h. Then add 3g of 10% poly(N-isopropylacrylamide) aqueous solution, stir and mix well, adjust the pH to 4 with hydrochloric acid, heat to 55℃, react for 2h, cool to room temperature, add 0.5g of 2-hydroxy-2-methyl-1-phenyl-1-propanone, stir in the dark until completely dissolved, and finally add 1.5g of Fe3O4@SiO2 particles and ultrasonically disperse evenly.

[0057] Preparation Example 4

[0058] The preparation method of the nano-silica sol includes the following steps:

[0059] Add 10g of mesoporous silica nanoparticles to 100g of basic silica sol, and disperse evenly by ultrasonication. Then, add 5g of ZIF-8 methanol solution with a molar concentration of 0.3mol / L, and stir continuously at 200r / min for 2h. Then, add 3g of 10% poly(N-isopropylacrylamide) aqueous solution, stir and mix well, adjust the pH to 4 with hydrochloric acid, heat to 50℃, react for 2h, cool to room temperature, add 1g of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and stir in the dark until completely dissolved. Finally, add 2g of Fe3O4@SiO2 particles and disperse evenly by ultrasonication.

[0060] Preparation Example 5

[0061] The preparation method of the modified polysilazane includes the following steps:

[0062] Add 50g of polysilazane, 20g of tridecylfluorooctyltriethoxysilane, and 10g of hexafluorobutyl methacrylate to a reaction vessel, add 50g of xylene to dissolve, heat to 60℃ and stir for 25 minutes until homogeneous;

[0063] Add 5g of N,N-diethylethanolamine and 1g of dibutyltin dilaurate, heat to 85℃, react for 3h under nitrogen protection to generate the product, remove xylene by vacuum distillation, and obtain the modified polysilazane.

[0064] Preparation Example 6

[0065] The preparation method of the modified polysilazane includes the following steps:

[0066] Add 60g of polysilazane, 15g of tridecylfluorooctyltriethoxysilane and 8g of hexafluorobutyl methacrylate to the reaction vessel, add 40g of xylene to dissolve, heat to 62℃ and stir for 25min until homogeneous;

[0067] Add 3g of N,N-diethylethanolamine and 0.5g of dibutyltin dilaurate, heat to 80℃, and react for 3h under nitrogen protection to generate the modified polysilazane. Remove xylene by vacuum distillation to obtain the modified polysilazane.

[0068] Preparation Example 7

[0069] The preparation method of the modified polysilazane includes the following steps:

[0070] Add 70g of polysilazane, 25g of tridecylfluorooctyltriethoxysilane, and 25g of hexafluorobutyl methacrylate to a reaction vessel, add 50g of xylene to dissolve, heat to 60℃ and stir for 25 minutes until homogeneous;

[0071] 2g of N,N-diethylethanolamine and 0.5g of dibutyltin dilaurate were added, and the mixture was heated to 85℃ and reacted for 3 hours under nitrogen protection to generate the modified polysilazane. Xylene was removed by vacuum distillation.

[0072] Example 1

[0073] A method for preparing a high-temperature resistant anti-corrosion coating for buildings includes the following steps:

[0074] S1. Add 50g of the carboxyl-modified organosilicon resin prepared in Preparation Example 1 and 5g of the nano-silica sol prepared in Preparation Example 2 to the reaction vessel, stir evenly at 300 rpm for 10 min, then add 20g of ceramic microspheres with a particle size of 50μm, 0.5g of graphene oxide and 5g of inert filler in sequence for high-speed dispersion at 1500 rpm for 30 min.

[0075] The inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1.

[0076] S2. Add 3g of polyacrylamide and 3g of fumed silica, stir for 10 minutes until the mixture is uniform, and then grind it with a sand mill until the fineness is ≤50μm to obtain component A.

[0077] S3. Add 30g of the modified polysilazane prepared in Preparation Example 5 and 5g of diaminodiphenyl sulfone to a container, stir evenly at 300 rpm for 10 min to obtain component B.

[0078] S4. Mix component A and component B at a mass ratio of 3:1 to obtain a high-temperature resistant building anti-corrosion coating.

[0079] Example 2

[0080] A method for preparing a high-temperature resistant anti-corrosion coating for buildings includes the following steps:

[0081] S1. Add 55g of the carboxyl-modified organosilicon resin prepared in Preparation Example 1 and 8g of the nano-silica sol prepared in Preparation Example 3 to the reaction vessel, stir evenly at 400 rpm for 12 min, then add 25g of ceramic microspheres with a particle size of 100μm, 1g of graphene oxide and 8g of inert filler in sequence for high-speed dispersion at 1200 rpm for 25 min.

[0082] The inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1.5.

[0083] S2. Add 4g of polyacrylamide and 4g of fumed silica, stir for 15 minutes until the mixture is uniform, and then grind it with a sand mill until the fineness is ≤50μm to obtain component A.

[0084] S3. Add 45g of the modified polysilazane prepared in Preparation Example 5 and 7g of diaminodiphenyl sulfone to a container, stir evenly at 200 rpm for 10 min to obtain component B.

[0085] S4. Mix component A and component B at a mass ratio of 3:1 to obtain a high-temperature resistant building anti-corrosion coating.

[0086] Example 3

[0087] A method for preparing a high-temperature resistant anti-corrosion coating for buildings includes the following steps:

[0088] S1. Add 60g of the carboxyl-modified organosilicon resin prepared in Preparation Example 1 and 15g of the nano-silica sol prepared in Preparation Example 4 to the reaction vessel, stir evenly at 500 rpm for 10 min, then add 30g of ceramic microspheres with a particle size of 150μm, 2g of graphene oxide and 10g of inert filler in sequence for high-speed dispersion at 1000 rpm for 20 min.

[0089] The inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1.

[0090] S2. Add 5g of polyacrylamide and 5g of fumed silica, stir for 15 minutes until uniformly mixed, and then grind through a sand mill to a fineness of ≤50μm to obtain component A;

[0091] S3. Add 50g of the modified polysilazane prepared in Preparation Example 5 and 10g of diaminodiphenyl sulfone to a container, stir evenly at 300 rpm for 10 min to obtain component B.

[0092] S4. Mix component A and component B at a mass ratio of 5:1 to obtain a high-temperature resistant building anti-corrosion coating.

[0093] Example 4

[0094] A method for preparing a high-temperature resistant anti-corrosion coating for buildings includes the following steps:

[0095] S1. Add 50g of the carboxyl-modified organosilicon resin prepared in Preparation Example 1 and 5g of the nano-silica sol prepared in Preparation Example 2 to the reaction vessel, stir evenly at 500 rpm for 12 min, then add 20g of ceramic microspheres with a particle size of 180μm, 0.5g of graphene oxide and 5g of inert filler in sequence for high-speed dispersion at 1300 rpm for 25 min.

[0096] The inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1.2.

[0097] S2. Add 3g of polyacrylamide and 3g of bentonite, stir for 15 minutes until uniformly mixed, and then grind through a sand mill to a fineness of ≤50μm to obtain component A;

[0098] S3. Add 30g of the modified polysilazane prepared in Preparation Example 6 and 5g of diaminodiphenyl sulfone to a container, stir evenly at 280 rpm for 9 min to obtain component B.

[0099] S4. Mix component A and component B at a mass ratio of 4:1 to obtain a high-temperature resistant building anti-corrosion coating.

[0100] Example 5

[0101] A method for preparing a high-temperature resistant anti-corrosion coating for buildings includes the following steps:

[0102] S1. Add 50g of the carboxyl-modified organosilicon resin prepared in Preparation Example 1 and 5g of the nano-silica sol prepared in Preparation Example 2 to the reaction vessel, stir evenly at 500 rpm for 10 min, then add 20g of ceramic microspheres with a particle size of 200μm, 0.5g of graphene oxide and 5g of inert filler in sequence for high-speed dispersion at 1000 rpm for 30 min.

[0103] The inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1.5.

[0104] S2. Add 3g of polyacrylamide and 3g of hydroxyethyl cellulose, stir for 14 minutes until uniformly mixed, and then grind through a sand mill to a fineness of ≤50μm to obtain component A;

[0105] S3. Add 30g of the modified polysilazane prepared in Preparation Example 7 and 5g of diaminodiphenyl sulfone to a container, stir evenly at 200 rpm for 5 min to obtain component B.

[0106] S4. Mix component A and component B at a mass ratio of 3:1 to obtain a high-temperature resistant building anti-corrosion coating.

[0107] Example 6

[0108] A method for preparing a high-temperature resistant anti-corrosion coating for buildings includes the following steps:

[0109] S1. Add 55g of the carboxyl-modified organosilicon resin prepared in Preparation Example 1 and 8g of the nano-silica sol prepared in Preparation Example 3 to the reaction vessel, stir evenly at 300 rpm for 15 min, then add 25g of ceramic microspheres with a particle size of 50μm, 1g of graphene oxide and 8g of inert filler in sequence for high-speed dispersion at 1500 rpm for 30 min.

[0110] The inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1.5.

[0111] S2. Add 4g of fatty acid polyethylene glycol ester and 4g of fumed silica, stir for 15 minutes until uniformly mixed, and then grind through a sand mill to a fineness of ≤50μm to obtain component A;

[0112] S3. Add 45g of the modified polysilazane prepared in Preparation Example 6 and 7g of diaminodiphenyl sulfone to a container, stir at 300 rpm for 8 minutes until homogeneous to obtain component B.

[0113] S4. Mix component A and component B at a mass ratio of 3:1 to obtain a high-temperature resistant building anti-corrosion coating.

[0114] Example 7

[0115] A method for preparing a high-temperature resistant anti-corrosion coating for buildings includes the following steps:

[0116] S1. Add 55g of the carboxyl-modified organosilicon resin prepared in Preparation Example 1 and 8g of the nano-silica sol prepared in Preparation Example 3 to the reaction vessel, stir evenly at 300 rpm for 10 min, then add 25g of ceramic microspheres with a particle size of 80μm, 1g of graphene oxide and 8g of inert filler in sequence for high-speed dispersion at 1000 rpm for 20 min.

[0117] The inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1.

[0118] S2. Add 4g of fatty acid polyethylene glycol ester and 4g of hydroxyethyl cellulose, stir for 10 minutes until uniformly mixed, and then grind through a sand mill to a fineness of ≤50μm to obtain component A;

[0119] S3. Add 45g of the modified polysilazane prepared in Preparation Example 6 and 7g of diaminodiphenyl sulfone to a container, stir evenly at 300 rpm for 10 min to obtain component B.

[0120] S4. Mix component A and component B at a mass ratio of 5:1 to obtain a high-temperature resistant building anti-corrosion coating.

[0121] Example 8

[0122] A method for preparing a high-temperature resistant anti-corrosion coating for buildings includes the following steps:

[0123] S1. Add 60g of the carboxyl-modified organosilicon resin prepared in Preparation Example 1 and 15g of the nano-silica sol prepared in Preparation Example 3 to the reaction vessel, stir evenly at 500 rpm for 15 min, then add 30g of ceramic microspheres with a particle size of 200μm, 2g of graphene oxide and 10g of inert filler in sequence for high-speed dispersion at 1500 rpm for 30 min.

[0124] The inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1.5.

[0125] S2. Add 5g of polyacrylamide and 5g of hydroxyethyl cellulose, stir for 15 minutes until evenly mixed, and then grind through a sand mill to a fineness of ≤50μm to obtain component A;

[0126] S3. Add 50g of the modified polysilazane prepared in Preparation Example 7 and 10g of diaminodiphenyl sulfone to a container, stir evenly at 300 rpm for 10 min to obtain component B.

[0127] S4. Mix component A and component B at a mass ratio of 3:1 to obtain a high-temperature resistant building anti-corrosion coating.

[0128] Example 9

[0129] A method for preparing a high-temperature resistant anti-corrosion coating for buildings includes the following steps:

[0130] S1. Add 60g of the carboxyl-modified organosilicon resin prepared in Preparation Example 1 and 15g of the nano-silica sol prepared in Preparation Example 4 to the reaction vessel, stir evenly at 450 rpm for 15 min, then add 30g of ceramic microspheres with a particle size of 180μm, 2g of graphene oxide and 10g of inert filler in sequence for high-speed dispersion at 1500 rpm for 30 min.

[0131] The inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1.

[0132] S2. Add 5g of polyacrylamide and 5g of fumed silica, stir for 15 minutes until uniformly mixed, and then grind through a sand mill to a fineness of ≤50μm to obtain component A;

[0133] S3. Add 50g of the modified polysilazane prepared in Preparation Example 6 and 10g of diaminodiphenyl sulfone to a container, stir evenly at 300 rpm for 10 min to obtain component B.

[0134] S4. Mix component A and component B at a mass ratio of 3:1 to obtain a high-temperature resistant building anti-corrosion coating.

[0135] Comparative Example 1

[0136] The difference between this comparative example and Example 1 is that the carboxyl-modified silicone resin prepared in Example 1 was replaced with a commercially available silicone resin, purchased from Shanghai Huiyan New Materials Co., Ltd., model number 3074.

[0137] Comparative Example 2

[0138] The difference between this comparative example and Example 1 is that the nano-silica sol prepared in Preparation Example 2 is not added.

[0139] Comparative Example 3

[0140] The difference between this comparative example and Example 1 is that the nano-silica sol prepared in Preparation Example 2 is replaced with the basic silica sol, which was purchased from DuPont (USA), Ludox CL-X.

[0141] Comparative Example 4

[0142] The difference between this comparative example and Example 1 is that ZIF-8 methanol solution was not added during the preparation of nano-silica sol in Example 2.

[0143] Comparative Example 5

[0144] The difference between this comparative example and Example 1 is that no aqueous solution of poly-N-isopropylacrylamide was added during the preparation of nano-silica sol in Example 2.

[0145] Comparative Example 6

[0146] The difference between this comparative example and Example 1 is that the modified polysilazane prepared in Preparation Example 5 was replaced with a commercially available polysilazane purchased from Wuhan Shuer Biotechnology Co., Ltd., model XH61100PXLOT.

[0147] The performance of the building anti-corrosion coatings prepared in Examples 1-9 and Comparative Examples 1-6 was tested, and the results are shown in Table 1:

[0148] High temperature resistance: Refer to GB / T 1735-2009 "Determination of heat resistance of paints and varnishes".

[0149] Corrosion resistance: Test for resistance to acids and alkalis using the immersion method, referring to GB / T9274-1988 "Determination of resistance to liquid media for paints and varnishes".

[0150] Adhesion is determined according to GB / T1720-1979, Test Method for Adhesion of Coating Film.

[0151] Table 1

[0152]

[0153]

[0154]

[0155] In summary, the high-temperature resistant building anti-corrosion coatings prepared in Examples 1-9 of this invention exhibit significantly improved overall performance compared to the coatings prepared in Comparative Examples 1-6. Their high-temperature resistance and corrosion resistance are particularly superior. In Comparative Example 2, the lack of nano-silica sol resulted in a severe decrease in corrosion resistance and coating adhesion. This invention, by adding nano-silica sol, forms a multi-level pore structure between mesoporous silica and ZIF-8, increasing the specific surface area from 50 m² / s of ordinary silica sol. 2 / g increased to 200m 2 / g, adsorbs small molecule byproducts (such as water and ethanol) generated during coating curing, reducing coating porosity; Zn in ZIF-8 2+ With Cl - It has strong coordination properties and can capture Cl that has penetrated into the coating. - It slows down the corrosion of the substrate, thereby extending the service life of the building substrate.

[0156] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A high-temperature resistant building anti-corrosion coating, characterized in that, It includes component A and component B, wherein component A is made from the following raw materials in parts by weight: 50-60 parts of carboxyl-modified silicone resin, 5-15 parts of nano-silica sol, 20-30 parts of ceramic microspheres, 5-10 parts of inert filler, 0.5-2 parts of graphene oxide, and 5-10 parts of functional additives. Component B is made from the following raw materials in parts by weight: 30-50 parts of modified polysilazane, 5-10 parts of latent curing agent; Preparation method of the nano silica sol Includes the following steps: Add 8-10% mesoporous silica nanoparticles to the basic silica sol and disperse it evenly by ultrasonication. Then, add 3-5% ZIF-8 methanol solution (by weight of the basic silica sol) dropwise and stir continuously at 200-300 r / min for 2-3 h. Next, add 3-5% poly(N-isopropylacrylamide) aqueous solution (by weight of the basic silica sol), stir and mix well. Adjust the pH to 4-5 with hydrochloric acid, raise the temperature to 50-55℃, and react for 2-3 h. After cooling to room temperature, add 0.5-1% photoinitiator (by weight of the basic silica sol) and stir in the dark until completely dissolved. Finally, add 1.5-2% Fe3O4@SiO2 particles (by weight of the basic silica sol) and disperse evenly by ultrasonication.

2. The high-temperature resistant building anti-corrosion coating according to claim 1, characterized in that, The preparation method of the carboxyl-modified organosilicon resin includes the following steps: S1. Add diphenyldihydroxysilane, methyldiethoxysilane, and cation exchange resin to the reactor, purge with nitrogen 3-5 times, heat to 90-95℃, and stir magnetically for 20-24 hours. After the reaction is complete, filter while hot to remove the resin. Distill the filtrate under reduced pressure of -0.09MPa to remove low-boiling substances, and collect the fraction at 180-200℃ to obtain hydrogen-containing polysiloxane. S2. Add allyl malonic acid to the reaction flask, heat to 105-110℃ under nitrogen protection to melt, add 2wt% chloroplatinic acid-isopropanol solution, and stir for 10-15 minutes until homogeneous. S3. Slowly add the hydrogen-containing polysiloxane from S1 at a rate of 2 g / min. After the addition is complete, keep the temperature at 110℃ for 5 h. Remove unreacted monomers by vacuum distillation at -0.095 MPa and 150℃ to obtain carboxyl-modified organosilicon resin.

3. The high-temperature resistant building anti-corrosion coating according to claim 1, characterized in that, The molar concentration of the ZIF-8 methanol solution is 0.1-0.3 mol / L; The mass fraction of the poly(N-isopropylacrylamide) aqueous solution is 10-15%; The photoinitiator is any one of 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, and α-hydroxyalkylphenyl ketone.

4. The high-temperature resistant building anti-corrosion coating according to claim 1, characterized in that, The ceramic microspheres have a particle size of 50-200μm, a sphericity of >95%, and a high temperature resistance of ≥1700℃.

5. The high-temperature resistant building anti-corrosion coating according to claim 1, characterized in that, The inert filler is a mixture of boron nitride and aluminum oxide in a mass ratio of 1:1-1.

5.

6. The high-temperature resistant building anti-corrosion coating according to claim 1, characterized in that, The functional additive is a mixture of a dispersant and a rheology modifier in a mass ratio of 1:1, wherein the dispersant is polyacrylamide or fatty acid polyethylene glycol ester; and the rheology modifier is any one of fumed silica, bentonite, and hydroxyethyl cellulose.

7. The high-temperature resistant building anti-corrosion coating according to claim 1, characterized in that, The preparation method of the modified polysilazane includes the following steps: Add polysilazane, tridecafluorooctyltriethoxysilane and hexafluorobutyl methacrylate to a reaction vessel, add xylene to dissolve, heat to 60-65℃ and stir for 25-30 minutes until homogeneous; N,N-diethylethanolamine and dibutyltin dilaurate were added, and the mixture was heated to 80-85℃ and reacted under nitrogen protection for 3-4 hours to generate the product. Xylene was removed by vacuum distillation to obtain the modified polysilazane.

8. The high-temperature resistant building anti-corrosion coating according to claim 1, characterized in that, The latent curing agent is diaminodiphenyl sulfone.

9. A method for preparing a high-temperature resistant building anti-corrosion coating as described in any one of claims 1-8, characterized in that, It also includes the following steps: S1. According to the stated weight proportions, add carboxyl-modified organosilicon resin and nano-silica sol to the reactor, stir evenly at 300-500 rpm for 10-15 min, then add ceramic microspheres, graphene oxide and inert filler in sequence for high-speed dispersion at 1000-1500 rpm for 20-30 min. S2. Add functional additives, stir for 10-15 minutes until uniformly mixed, and then grind through a sand mill to a fineness of ≤50μm to obtain component A; S3. Add the modified polysilazane and latent curing agent to the container, stir at 200-300 rpm for 5-10 minutes until homogeneous to obtain component B. S4. Mix component A and component B at a mass ratio of 3-5:1 to obtain a high-temperature resistant building anti-corrosion coating.

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