Geopolymer-based anticorrosive paint as well as preparation method and application thereof

Abstract

The invention discloses a geopolymer-based anticorrosive coating, which is prepared from the following components in parts by mass: 30 to 50 parts of mineral powder material, 1 to 10 parts of zinc phosphate, 1 to 10 parts of aluminum triphosphate, 1 to 10 parts of water glass curing agent, 0.01 to 0.5 part of condensed aluminum phosphate, 0.01 to 0.5 part of dispersing agent, 0.01 to 0.5 part of thickening agent, 0.01 to 0.2 part of water reducing agent, 0.01 to 0.3 part of coupling agent, 10 to 50 parts of water glass and 5 to 20 parts of deionized water, the invention also discloses a preparation method of the geopolymer-based anticorrosive paint. The invention also discloses application of the geopolymer-based anticorrosive paint. The paint has the advantages of being good in corrosion resistance, high in surface hydrophobic capacity, good in weather resistance, resistant to corrosion, long in service life and high in adhesive force.

Description

Technical Field

[0001] The present invention relates to the technical field of anti-corrosion coatings, and in particular to a geopolymer-based anti-corrosion coating and a preparation method and application thereof. Background Art

[0002] Steel is widely used in the construction of factory buildings and other building structures due to its advantages such as low price and easy processing. However, steel itself easily reacts with oxygen and water vapor in the air, causing corrosion. Corrosion is a complex physical and chemical interaction between metal and its environment, which causes changes in metal properties. If not prevented in time, it may cause a series of damages due to steel fracture, which has a significant impact on the company's economic and production safety. Traditional anti-corrosion mainly relies on organic coatings. However, traditional organic coatings use organic matter as film-forming agents, which are often accompanied by the volatilization of organic compounds such as VOCs, formaldehyde, and benzene, which seriously affects construction workers and the environment. At the same time, organic coatings have poor weather resistance, and after the coating falls off, it needs to be repeatedly sprayed, resulting in high anti-corrosion costs for enterprises. Summary of the Invention

[0003] To solve the above technical problems, the present invention aims to provide a geopolymer-based anticorrosive coating comprising a mineral powder material as a matrix, zinc phosphate and aluminum tripolyphosphate as anticorrosive pigments, and water glass as an alkali activator, a method for preparing the geopolymer-based anticorrosive coating, and an application of the geopolymer-based anticorrosive coating. The geopolymer-based anticorrosive coating has the advantages of good corrosion resistance, strong surface hydrophobicity, good weather resistance, corrosion resistance, long service life, and strong adhesion.

[0004] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is as follows:

[0005] A geopolymer-based anticorrosive coating, comprising, by mass fraction:

[0006] 30-50 parts of mineral powder materials, 1-10 parts of zinc phosphate, 1-10 parts of aluminum tripolyphosphate, 1-10 parts of water glass curing agent, 0.01-0.5 parts of condensed aluminum phosphate, 0.01-0.5 parts of dispersant, 0.01-0.5 parts of thickener, 0.01-0.2 parts of water reducer, 0.01-0.3 parts of coupling agent, 10-50 parts of water glass, and 5-20 parts of deionized water. The mineral powder materials include one or more of metakaolin, mineral powder, wollastonite powder, talc powder and quartz powder, and the water glass includes one or more of potassium water glass, sodium water glass and lithium water glass.

[0007] Preferably, the mineral powder is S95 grade or above, and the wollastonite powder, talc powder, quartz powder, zinc phosphate, and aluminum tripolyphosphate are all powders with a mesh size of 200 or above.

[0008] Preferably, the water glass curing agent is one or more of silicon phosphate, silicon tripolyphosphate, sodium fluorosilicate, calcium oxide and inorganic acid.

[0009] Preferably, the dispersant includes an inorganic dispersant and / or an organic dispersant, the inorganic dispersant includes one or more of silicates and phosphates; the organic dispersant includes one or more of triethylhexyl phosphate, sodium lauryl sulfate, methyl amyl alcohol, cellulose derivatives, polyacrylamide, guar gum and fatty acid polyethylene glycol esters.

[0010] Preferably, the thickener includes an organic thickener and / or an inorganic thickener, wherein the organic thickener includes one or more of carboxymethyl cellulose, carboxyethyl cellulose, hydroxypropyl methyl cellulose, xanthan gum, dextrin and polyacrylamide; and the inorganic thickener includes one or more of bentonite, attapulgite and aluminum silicate.

[0011] Preferably, the water reducer includes one or more of calcium lignin sulfonate, sodium lignin sulfonate, naphthalene-based water reducer, polycarboxylic acid-based water reducer, aliphatic water reducer and aminosulfonate-based water reducer.

[0012] Preferably, the coupling agent includes one or more of silane coupling agent KH-550, silane coupling agent KH-560, silane coupling agent KH-570 and titanate coupling agent;

[0013] Preferably, the modulus of the potassium water glass and the sodium water glass is 1.2-3.5, and the Baume degree (20° C.) is 38.4-48.3 Bé, and the modulus of the lithium water glass is 2.6-5.0.

[0014] A method for preparing the geopolymer-based anticorrosive coating as described above is characterized by comprising the following steps:

[0015] S1. Grind and mix metakaolin, mineral powder, wollastonite powder, talc powder, quartz powder, zinc phosphate, aluminum tripolyphosphate, condensed aluminum phosphate, polyaluminum phosphate, water glass curing agent, dispersant, and thickener to obtain a mixed powder;

[0016] S2. Mixing a water reducer, a coupling agent and deionized water to obtain a mixed solution, and then mixing the mixed solution with water glass to obtain an alkali-activated mixed solution;

[0017] S3. Evenly mix the mixed powder and the alkali-activated mixed solution to obtain a geopolymer-based anticorrosive coating.

[0018] An application of the geopolymer-based anticorrosive coating as described above, wherein the geopolymer-based anticorrosive coating is sprayed on a steel surface and dried to obtain a geopolymer-based anticorrosive coating; the diameter of the spray nozzle is 1 to 5 mm; the spray pressure is 2 to 6 MPa; the distance between the spray nozzle and the steel is 60 to 100 cm; the spray thickness is 500 μm to 1 mm; the spray coating amount is 1.8 to 2.0 kg / m 2 .

[0019] Compared with the prior art, the present invention has achieved beneficial technical effects:

[0020] Using water glass as both an alkaline activator and film-forming agent, a hydrophobic material primarily composed of inorganic film-forming substances effectively isolates moisture, creating a physical barrier. Combined with high-quality anti-corrosion materials such as zinc phosphate and aluminum tripolyphosphate, this electrochemically protects against corrosion, achieving a dual mechanism of physical and electrochemical protection, significantly enhancing corrosion resistance. The coating's strong surface hydrophobicity reduces droplets adhering to the coating surface, further reducing corrosion to the coating and underlying steel. It contains less than 1% organic matter and emits no toxic or hazardous substances such as VOCs, formaldehyde, and benzene. It is heat-resistant (showing no bubbles, cracks, or flaking after 10 cycles of 600°C temperature denaturation testing), exhibits excellent weather resistance, and offers corrosion resistance (acid, alkali, and salt), a long service life, and strong adhesion. It maintains its corrosion resistance over time without requiring repeated re-application, thus reducing the cost of repeated re-applications over the long term.

[0021] The biggest advantage of zinc phosphate as an anti-rust pigment is that it is non-toxic and has good anti-rust performance; aluminum tripolyphosphate can dissociate into tripolyphosphate ions in the coating film, which has a strong chelating ability. It contacts the surface of the steel substrate to form a complex protective film with iron tripolyphosphate as the main component. This phosphate protective film is difficult to dissolve in water, has high hardness, and has strong adhesion to the base metal. It can prevent further corrosion and has long-term effectiveness, enhancing the anti-corrosion performance of the coating.

[0022] During application, only loose rust on the steel structure needs to be removed. The coating itself blends seamlessly with the rust, using it as a component of the anti-corrosion coating, ensuring strong adhesion to the steel structure. The coating's drying time can be adjusted based on the amount of curing agent used, allowing for precise control of the application timeframe, allowing for application in areas with specific timeframes and facilitating coating application. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the embodiments, but the scope of protection claimed in the present invention is not limited to the following specific embodiments.

[0024] Example 1:

[0025] A geopolymer-based anti-corrosion coating comprises, by mass fraction, 34.95 parts of metakaolin, 8.74 parts of wollastonite powder, 1.75 parts of zinc phosphate, 6.99 parts of aluminum tripolyphosphate, 6.29 parts of water glass curing agent, 0.31 parts of condensed aluminum phosphate, 0.26 parts of dispersant, 0.17 parts of thickener, 0.17 parts of water reducer, 0.17 parts of coupling agent, 31.45 parts of potassium water glass, and 8.74 parts of deionized water.

[0026] Metakaolin is kaolin ore powder with a mesh size of 300 or larger, or kaolin powder after water washing and prior selection, which is heated to 600-900°C, calcined in air for 2 hours, and then cooled, and then ground to a mesh size of 200 or larger. In this embodiment, the kaolin powder is heated to 700-900°C, calcined in air for 2 hours, and then cooled, and then ground to a mesh size of 200 or larger. The kaolin powder has a silica content of 52%, an alumina content of 45%, and a calcium oxide content of 0.26%.

[0027] Wollastonite powder, zinc phosphate and aluminum tripolyphosphate are all powders with a size of 200 mesh or more.

[0028] The water glass curing agent is silicon tripolyphosphate.

[0029] The dispersant is a mixture of sodium tripolyphosphate and sodium dodecylbenzene sulfate in a ratio of 1:1.

[0030] The thickener is obtained by mixing carboxymethyl cellulose and polyacrylamide in a ratio of 1:1.

[0031] The water reducer is a polycarboxylic acid high-efficiency water reducer.

[0032] The coupling agent is silane coupling agent KH-550.

[0033] The modulus of potassium water glass is 3.07 and the Baume degree (20℃) is 40Bé.

[0034] A method for preparing a geopolymer-based anticorrosive coating, characterized by comprising the following steps:

[0035] S1. Prepare metakaolin, wollastonite powder, zinc phosphate, aluminum tripolyphosphate, condensed aluminum phosphate, polyaluminum phosphate, water glass curing agent, dispersant, and thickener in proportion, grind and mix them in a ball mill, and grind them to a powder content of more than 95% under a 200-mesh sieve to obtain a mixed powder; the number of steel balls and steel forgings in the ball mill is as follows: 13 ∅50mm steel balls, 30 ∅40mm steel balls, 40 ∅35X25mm steel forgings, and 17 ∅30mm steel balls, all of which are made of cast steel; the mill speed is 48 r / min, and 5 kg of material is loaded each time. After grinding, the mixture is sieved through a 200-mesh sieve using a vibrating screen to ensure that the content under the sieve is more than 95%;

[0036] S2. Mixing a water reducer, a coupling agent and deionized water to obtain a mixed solution, and then mixing the mixed solution with water glass to obtain an alkali-activated mixed solution;

[0037] S3. Evenly mix the mixed powder and the alkali-activated mixed solution to obtain a geopolymer-based anti-corrosion coating.

[0038] A geopolymer-based anticorrosive coating is applied by spraying the geopolymer-based anticorrosive coating onto a steel surface and drying the coating to obtain a geopolymer-based anticorrosive coating. The diameter of the spray nozzle is 1 to 5 mm, the spray pressure is 2 to 6 MPa, the distance between the spray nozzle and the steel is 60 to 100 cm, the spray thickness is 500 μm to 1 mm, and the spray coating amount is 1.8 to 2.0 kg / m2. In this embodiment, the diameter of the spray nozzle is 3 to 5 mm, and the spray pressure is 3 to 5 MPa.

[0039] Example 2:

[0040] A geopolymer-based anti-corrosion coating comprises, by mass fraction, 27.49 parts of metakaolin, 6.87 parts of mineral powder, 5.15 parts of talc, 3.44 parts of quartz powder, 2.58 parts of zinc phosphate, 8.59 parts of aluminum tripolyphosphate, 5.15 parts of water glass curing agent, 0.26 part of condensed aluminum phosphate, 0.34 part of dispersant, 0.26 part of thickener, 0.09 part of water reducer, 0.26 part of coupling agent, 25.77 parts of sodium water glass, and 13.75 parts of deionized water.

[0041] The metakaolin is a kaolin ore powder with a mesh size of 300 or more or a kaolin powder after washing and selection, which is heated to 600-900°C, calcined in air for 2 hours, cooled, and then ground to a mesh size of 200 or more. In this embodiment, the kaolin powder is heated to 700-900°C, calcined in air for 2 hours, cooled, and then ground to a mesh size of 200 or more, wherein the silica content is 52%, the alumina content is 45%, and the calcium oxide content is 0.26%.

[0042] The mineral powder is S95 grade, with a 7-day activity greater than 84%, a 28-day activity greater than 98%, a chloride ion content less than 0.01%, a silicon dioxide content greater than 33%, and a calcium oxide content greater than 40%. Talc, quartz powder, zinc phosphate, and aluminum tripolyphosphate are all powders with a mesh size of 200 or above.

[0043] The water glass curing agent is a mixture of silicon phosphate and sodium fluorosilicate in a ratio of 1:1.

[0044] The dispersant is a mixture of sodium hexametaphosphate and sodium pyrophosphate in a ratio of 1:3.

[0045] The thickener is a mixture of hydroxypropyl methylcellulose and bentonite in a ratio of 2:1.

[0046] The water reducer is a mixture of calcium lignin sulfonate and sodium lignin sulfonate in a ratio of 3:1.

[0047] The coupling agent is silane coupling agent KH-560.

[0048] The modulus of sodium water glass is 2.2 and the Baume degree (20℃) is 40Bé.

[0049] A method for preparing a geopolymer-based anticorrosive coating, characterized by comprising the following steps:

[0050] S1. Mix metakaolin, mineral powder, talc, quartz powder, zinc phosphate, aluminum tripolyphosphate, condensed aluminum phosphate, polyaluminum phosphate, water glass curing agent, dispersant, and thickener in proportion, grind and mix them using a ball mill, and grind them until the particle size under a 200-mesh sieve is greater than 95% to obtain a mixed powder; the number of steel balls and steel forgings in the ball mill is as follows: 13 ∅50mm steel balls, 30 ∅40mm steel balls, 40 ∅35X25mm steel forgings, and 17 ∅30mm steel balls, all of which are made of cast steel; the mill speed is 48 r / min, and 5 kg of material is loaded each time. After grinding, the mixture is sieved through a 200-mesh sieve using a vibrating screen to ensure that the particle size under the sieve is greater than 95%;

[0051] S2. Mixing a water reducer, a coupling agent and deionized water to obtain a mixed solution, and then mixing the mixed solution with water glass to obtain an alkali-activated mixed solution;

[0052] S3. Evenly mix the mixed powder and the alkali-activated mixed solution to obtain a geopolymer-based anti-corrosion coating.

[0053] A geopolymer-based anticorrosive coating is applied by spraying the geopolymer-based anticorrosive coating onto a steel surface and drying the coating to obtain a geopolymer-based anticorrosive coating. The diameter of the spray nozzle is 1 to 5 mm, the spray pressure is 2 to 6 MPa, the distance between the spray nozzle and the steel is 60 to 100 cm, the spray thickness is 500 μm to 1 mm, and the spray coating amount is 1.8 to 2.0 kg / m2. In this embodiment, the diameter of the spray nozzle is 3 to 5 mm, and the spray pressure is 3 to 5 MPa.

[0054] Example 3:

[0055] A geopolymer-based anti-corrosion coating comprises, by mass fraction, 17.77 parts of metakaolin, 8.88 parts of mineral powder, 4.44 parts of wollastonite powder, 4.44 parts of talc, 8.88 parts of quartz powder, 4.44 parts of zinc phosphate, 8.88 parts of aluminum tripolyphosphate, 5.69 parts of water glass curing agent, 0.28 part of condensed aluminum phosphate, 0.27 part of dispersant, 0.21 part of thickener, 0.09 part of water reducer, 0.18 part of coupling agent, 14.21 parts of sodium water glass, 14.21 parts of lithium water glass, and 7.11 parts of deionized water.

[0056] The metakaolin is a kaolin ore powder with a mesh size of 300 or more or a kaolin powder after washing and selection, which is heated to 600-900°C, calcined in air for 2 hours, cooled, and then ground to a mesh size of 200 or more. In this embodiment, the kaolin powder is heated to 700-900°C, calcined in air for 2 hours, cooled, and then ground to a mesh size of 200 or more, wherein the silica content is 52%, the alumina content is 45%, and the calcium oxide content is 0.26%.

[0057] 30-50 parts of mineral powder materials, 1-10 parts of zinc phosphate, 1-10 parts of aluminum tripolyphosphate, 1-10 parts of water glass curing agent, 0.01-0.5 parts of condensed aluminum phosphate, 0.01-0.5 parts of dispersant, 0.01-0.5 parts of thickener, 0.01-0.2 parts of water reducer, 0.01-0.3 parts of coupling agent, 10-50 parts of water glass, and 5-20 parts of deionized water. The mineral powder materials include one or more of metakaolin, mineral powder, wollastonite powder, talc powder and quartz powder, and the water glass includes one or more of potassium water glass, sodium water glass and lithium water glass.

[0058] The mineral powder is S95 grade, with a 7-day activity greater than 84%, a 28-day activity greater than 98%, a chloride ion content less than 0.01%, a silicon dioxide content greater than 33%, and a calcium oxide content greater than 40%. Wollastonite powder, talc powder, quartz powder, zinc phosphate, and aluminum tripolyphosphate are all powders with a mesh size of 200 or above.

[0059] The water glass curing agent is a mixture of silicon phosphate, silicon tripolyphosphate, sodium fluorosilicate and calcium oxide in the ratio of 1:1:1:1.

[0060] The dispersant is triethylhexyl phosphate.

[0061] The thickener is a mixture of xanthan gum, dextrin and attapulgite in a ratio of 3:2:1.

[0062] The water reducer is a mixture of sodium lignin sulfonate and naphthalene-based water reducer in a ratio of 1:1.

[0063] The coupling agent is a mixture of silane coupling agent KH-550 and titanate coupling agent in a ratio of 1:1.

[0064] The modulus of sodium water glass is 1.2 and the Baume degree (20℃) is 40Bé, while the modulus of lithium water glass is 4.8 and the Baume degree (20℃) is 40Bé.

[0065] A method for preparing a geopolymer-based anticorrosive coating, characterized by comprising the following steps:

[0066] S1. Mix metakaolin, mineral powder, wollastonite powder, talc powder, quartz powder, zinc phosphate, aluminum tripolyphosphate, condensed aluminum phosphate, polyaluminum phosphate, water glass curing agent, dispersant, and thickener in proportion, grind and mix them using a ball mill, and grind them until the particle size under a 200-mesh sieve is greater than 95% to obtain a mixed powder; the number of steel balls and steel forgings in the ball mill is as follows: 13 ∅50mm steel balls, 30 ∅40mm steel balls, 40 ∅35X25mm steel forgings, and 17 ∅30mm steel balls, all of which are made of cast steel; the mill speed is 48 r / min, and 5 kg of material is loaded each time. After grinding, the mixture is sieved through a 200-mesh sieve using a vibrating screen to ensure that the particle size under the sieve is greater than 95%;

[0067] S2. Mixing a water reducer, a coupling agent and deionized water to obtain a mixed solution, and then mixing the mixed solution with water glass to obtain an alkali-activated mixed solution;

[0068] S3. Evenly mix the mixed powder and the alkali-activated mixed solution to obtain a geopolymer-based anti-corrosion coating.

[0069] A geopolymer-based anticorrosive coating is applied by spraying the geopolymer-based anticorrosive coating onto a steel surface and drying the coating to obtain a geopolymer-based anticorrosive coating. The diameter of the spray nozzle is 1 to 5 mm, the spray pressure is 2 to 6 MPa, the distance between the spray nozzle and the steel is 60 to 100 cm, the spray thickness is 500 μm to 1 mm, and the spray coating amount is 1.8 to 2.0 kg / m2. In this embodiment, the diameter of the spray nozzle is 3 to 5 mm, and the spray pressure is 3 to 5 MPa.

[0070] Application examples:

[0071] An application of a geopolymer-based anticorrosive coating comprises spraying the geopolymer-based anticorrosive coatings prepared in Examples 1, 2, and 3 onto a steel surface, drying the coating, and obtaining a geopolymer-based anticorrosive coating. The diameter of the spray nozzle is 1 to 5 mm, the spray pressure is 2 to 6 MPa, the distance between the spray nozzle and the steel is 60 to 100 cm, the spray thickness is 500 μm to 1 mm, and the spray coating amount is 1.8 to 2.0 kg / m2. Preferably, the diameter of the spray nozzle is 3 to 5 mm, and the spray pressure is 3 to 5 MPa.

[0072] The performance test results of the geopolymer-based anticorrosive coatings in Example 1, Example 2, and Example 3 are shown in Table 1 and Table 2 respectively:

[0073] Table 1 Performance test of geopolymer-based anticorrosive coatings

[0074] Test items Technical indicators Example 1 Example 2 Example 3 Material status No lumps, even after stirring qualified qualified qualified Construction performance Barrier-free application qualified qualified qualified Storage stability (90d) No caking, coagulation, mildew, etc. qualified qualified qualified Paint film appearance Normal, no cracking or falling off qualified qualified qualified Tack-free time ≤1h 0.8h 0.7h 0.8h Working time ≤6h 5h 4.5h 4h Adhesion ≥3MPa 6.2MPa 7.6MPa 5.9MPa Water resistance (168h) No bubbles, cracks or peeling, slight powder loss is allowed qualified qualified qualified Alkali resistance (saturated Ca(OH)2, 168h) No bubbles, cracks or peeling, slight powder loss is allowed qualified qualified qualified Impact resistance (1kg) 50cm 53cm 54cm 52cm Temperature change resistance (600℃) (10 times) No bubbles, cracks or peeling, slight powder loss is allowed qualified qualified qualified flexibility ≤4mm 3.6mm 3.5mm 3.7mm Salt spray resistance After 1000h, the unidirectional corrosion expansion at the scratch is ≤2.0mm, and there is no blistering, rust, cracking, peeling, etc. in the unscratched area qualified qualified qualified Dry film density <![CDATA[≥3300kg / m 3 ]]> <![CDATA[4530kg / m 3 ]]> <![CDATA[3910kg / m 3 ]]> <![CDATA[3830kg / m 3 ]]> Flame retardant properties Level A1 Level A1 Level A1

[0075] Table 2 Test results of harmful substances in geopolymer-based anti-corrosion coatings

[0076] Test items Technical indicators Example 1 Example 2 Example 3 VOC ≤120g / L Not detected Not detected Not detected Formaldehyde content ≤50 mg / kg Not detected Not detected Not detected Total BTEX ≤300 mg / kg Not detected Not detected Not detected Total lead ≤90 mg / kg Not detected Not detected Not detected Cadmium content ≤75 mg / kg Not detected Not detected Not detected Chromium content ≤60 mg / kg Not detected Not detected Not detected Mercury content ≤60 mg / kg Not detected Not detected Not detected

[0077] Using water glass as both an alkaline activator and film-forming agent, a hydrophobic material primarily composed of inorganic film-forming substances effectively isolates moisture, creating a physical barrier. Combined with high-quality anti-corrosion materials such as zinc phosphate and aluminum tripolyphosphate, this electrochemically protects against corrosion, achieving a dual mechanism of physical and electrochemical protection, significantly enhancing corrosion resistance. The coating's strong surface hydrophobicity reduces droplets adhering to the coating surface, further reducing corrosion to the coating and underlying steel. It contains less than 1% organic matter and emits no toxic or hazardous substances such as VOCs, formaldehyde, and benzene. It is heat-resistant (showing no bubbles, cracks, or flaking after 10 cycles of 600°C temperature denaturation testing), exhibits excellent weather resistance, and offers corrosion resistance (acid, alkali, and salt), a long service life, and strong adhesion. It maintains its corrosion resistance over time without requiring repeated re-application, thus reducing the cost of repeated re-applications over the long term.

[0078] The biggest advantage of zinc phosphate as an anti-rust pigment is that it is non-toxic and has good anti-rust performance; aluminum tripolyphosphate can dissociate into tripolyphosphate ions in the coating film, which has a strong chelating ability. It contacts the surface of the steel substrate to form a complex protective film with iron tripolyphosphate as the main component. This phosphate protective film is difficult to dissolve in water, has high hardness, and has strong adhesion to the base metal. It can prevent further corrosion and has long-term effectiveness, enhancing the anti-corrosion performance of the coating.

[0079] During application, only loose rust on the steel structure needs to be removed. The coating itself blends seamlessly with the rust, using it as a component of the anti-corrosion coating, ensuring strong adhesion to the steel structure. The coating's drying time can be adjusted based on the amount of curing agent used, allowing for precise control of the application timeframe, allowing for application in areas with specific timeframes and facilitating coating application.

[0080] On the one hand, ball mill grinding can utilize the principle of mechanical excitation to activate potentially active materials such as metakaolin and mineral powder, thereby completely exposing the Si-O tetrahedrons therein, which is beneficial to accelerate the alkali excitation reaction; on the other hand, using a ball mill for grinding is conducive to the uniform mixing of various components;

[0081] Coupling agents can enhance the adhesion between the coating and the metal substrate, improve the corrosion resistance and aging resistance of the coating, form stable complexes with rust, and delay the corrosion of steel.

[0082] Based on the disclosure and teachings of the above description, those skilled in the art may also make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and any modifications and variations of the invention should also fall within the scope of protection of the claims of the present invention. In addition, although certain specific terms are used in this description, these terms are for convenience of description only and do not constitute any limitation to the invention.

Claims

1. A geopolymer-based anticorrosive coating, characterized in that: Measured by mass fraction, including: 30-50 parts of mineral powder materials, 1-10 parts of zinc phosphate, 1-10 parts of aluminum tripolyphosphate, 1-10 parts of water glass curing agent, 0.01-0.5 parts of condensed aluminum phosphate, 0.01-0.5 parts of dispersant, 0.01-0.5 parts of thickener, 0.01-0.2 parts of water reducer, 0.01-0.3 parts of coupling agent, 10-50 parts of water glass, and 5-20 parts of deionized water. The mineral powder materials include one or more of metakaolin, mineral powder, wollastonite powder, talc powder and quartz powder, and the water glass includes one or more of potassium water glass, sodium water glass and lithium water glass.

2. The geopolymer-based anticorrosive coating according to claim 1, characterized in that: The mineral powder is of S95 grade or above, and the wollastonite powder, talc powder, quartz powder, zinc phosphate and aluminum tripolyphosphate are all powders of 200 mesh or above.

3. The geopolymer-based anticorrosive coating according to claim 1, characterized in that: The water glass curing agent is one or more of silicon phosphate, silicon tripolyphosphate, sodium fluorosilicate, calcium oxide and inorganic acid.

4. The geopolymer-based anticorrosive coating according to claim 1, characterized in that: The dispersant includes an inorganic dispersant and / or an organic dispersant, wherein the inorganic dispersant includes one or more of silicates and phosphates; and the organic dispersant includes one or more of triethylhexyl phosphate, sodium lauryl sulfate, methyl amyl alcohol, cellulose derivatives, polyacrylamide, guar gum and fatty acid polyethylene glycol esters.

5. The geopolymer-based anticorrosive coating according to claim 1, characterized in that: The thickener includes an organic thickener and / or an inorganic thickener, wherein the organic thickener includes one or more of carboxymethyl cellulose, carboxyethyl cellulose, hydroxypropyl methyl cellulose, xanthan gum, dextrin and polyacrylamide; and the inorganic thickener includes one or more of bentonite, attapulgite and aluminum silicate.

6. The geopolymer-based anticorrosive coating according to claim 1, characterized in that: The water reducer includes one or more of calcium lignin sulfonate, sodium lignin sulfonate, naphthalene-based water reducer, polycarboxylic acid-based water reducer, aliphatic water reducer and aminosulfonate-based water reducer.

7. The geopolymer-based anticorrosive coating according to claim 1, characterized in that: The coupling agent includes one or more of silane coupling agent KH-550, silane coupling agent KH-560, silane coupling agent KH-570 and titanate coupling agent.

8. The geopolymer-based anticorrosive coating according to claim 1, characterized in that: The modulus of the potassium water glass and the sodium water glass is 1.2-3.5, and the Baume degree (20° C.) is 38.4-48.3 Bé. The modulus of the lithium water glass is 2.6-5.

0.

9. A method for preparing a geopolymer-based anticorrosive coating according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Grind and mix metakaolin, mineral powder, wollastonite powder, talc powder, quartz powder, zinc phosphate, aluminum tripolyphosphate, condensed aluminum phosphate, polyaluminum phosphate, water glass curing agent, dispersant, and thickener to obtain a mixed powder; S2. Mixing a water reducer, a coupling agent and deionized water to obtain a mixed solution, and then mixing the mixed solution with water glass to obtain an alkali-activated mixed solution; S3. Evenly mix the mixed powder and the alkali-activated mixed solution to obtain a geopolymer-based anticorrosive coating.

10. A use of the geopolymer-based anticorrosive coating according to any one of claims 1 to 8, characterized in that: The geopolymer-based anticorrosive coating is sprayed on the surface of the steel and dried to obtain the geopolymer-based anticorrosive coating; the diameter of the spray nozzle is 1 to 5 mm; the spray pressure is 2 to 6 MPa; the distance between the spray nozzle and the steel is 60 to 100 cm; the spray thickness is 500 μm to 1 mm; the spray coating amount is 1.8 to 2.0 kg / m 2 .