Migration type steel bar rust conversion material and preparation method thereof

Abstract

The invention discloses a migration type steel bar rust conversion material and a preparation method thereof. The migration type steel bar rust conversion material is obtained by mixing and stirring nano rust conversion seed crystals, a penetrating agent and an emulsifying agent; wherein the nano rust conversion seed crystal is of a three-layer coating structure and takes a nano material as a crystal nucleus, the middle layer is an activation product formed by a rust conversion component and a hydroxyl group on the surface of the nano material, and the outermost layer is coated with a mixture of a migration rust-inhibiting component, organic silicon and a derivative thereof. The prepared migration type steel bar rust conversion material can be directly applied to the metal surface and the surface of an existing concrete structure, the situation that a traditional rust conversion material chisels a concrete protection layer to expose steel bars is avoided, the construction technology is simple and easy to operate, and the migration type steel bar rust conversion material has the advantages of inhibiting ion transmission, being good in hydrophobicity and being good in rust conversion effect; the preparation process is simple and convenient, and production is easy.

Description

Technical Field

[0001] This invention belongs to the field of steel reinforcement corrosion repair technology in existing concrete structures, and specifically relates to a migratory steel reinforcement rust conversion material and its preparation method. Background Technology

[0002] The maintenance and repair of steel reinforcement corrosion damage causes considerable economic losses to various countries and regions every year. In 2015, the direct economic losses caused by corrosion in the United States reached $350 billion, accounting for 3.7% of its GDP. In 2014, the economic losses caused by steel reinforcement corrosion in my country's construction sector exceeded one trillion yuan, accounting for 1.4% of its GDP. Steel reinforcement corrosion is the main form of durability degradation in existing reinforced concrete structures. Current technologies for repairing steel reinforcement corrosion mainly focus on corrosion transformation and migration repair, which can effectively reduce the corrosion rate and even restore the steel reinforcement to a passivated state, thus extending the service life of the structure.

[0003] Electromigration repair involves rust-inhibiting cations from the electrolyte penetrating the concrete protective layer under an applied electric field and migrating towards the cathode reinforcement. Simultaneously, chloride ions in the concrete specimen migrate towards the anode, thus achieving the goal of detachment from the concrete. However, this method causes significant damage to the concrete structure, is difficult to control in terms of construction current, and can easily lead to hydrogen embrittlement of the reinforcement. Rust conversion agents are easy to apply and convenient, therefore, they have received considerable attention in recent years. However, current rust conversion technologies suffer from poor conversion efficiency, poor penetration, difficulty in application, and negative impacts on operator health, as well as corrosion of surrounding equipment and the environment.

[0004] Patent CN109295444B discloses a rust converter, its preparation method, and its application. This invention provides a rust converter prepared from glycidyl tert-carbonate, gallic acid, and dodecylbenzenesulfonic acid. The raw materials for this rust converter are simple and low-cost, and it can be directly coated onto the surface of rusted steel without any pretreatment. After conversion, the rust layer has a dense surface structure, effectively preventing rusting and exhibiting good water resistance. However, on the one hand, its direct coating onto the surface of rusted steel lacks migration properties, making it unsuitable for concrete structures; on the other hand, its synthesis process is relatively complex, and it is difficult to produce at temperatures above 100℃. This invention has limited applications.

[0005] Patent CN114835859B describes a reactive emulsion with rust conversion function and its preparation method. First, a rust conversion seed emulsion is synthesized using rust conversion functional monomers, isooctyl acrylate, acrylonitrile, acetyl methacrylate, butyl acrylate, acrylic acid, emulsifiers, and initiators as raw materials. Then, a reactive emulsion with rust conversion function is synthesized using the rust conversion seed emulsion, vinylidene chloride, styrene, isooctyl acrylate, acrylonitrile, acetyl methacrylate, butyl acrylate, acrylic acid, emulsifiers, and initiators as raw materials. The emulsion synthesized in this invention has a core-shell structure. During the emulsion film formation process, the core with rust conversion function is slowly released, reacting with rust to convert it into a stable and harmless substance. However, the preparation process of this reactive emulsion with rust conversion function is relatively complex. Low-boiling components are removed by vacuum distillation, and the remaining crude product must be recrystallized to obtain the rust conversion functional monomer, making it difficult to produce.

[0006] Patent JP1986072073A discloses a rust-converting coating and its manufacturing method, which is composed of a reaction product of alkane polyol and polyhydroxybenzoic acid, water, and a film-forming polymer. This invention, when applied to rusted metal surfaces, can transform rust into stable iron-containing substances. However, this invention requires the removal of water generated by condensation through azeotropic distillation, as well as the removal of aromatic solvents and unreacted alkane polyols through vacuum distillation. The preparation technology is complex and difficult to produce, and the rust conversion effect is generally poor, with rust still occurring afterward. Summary of the Invention

[0007] To address the issues that existing rust conversion agents have complex preparation processes, poor conversion effects, still cause rusting, act directly on metal, have a narrow range of applications, and are not suitable for existing concrete structural systems, this invention provides a migratory steel rust conversion material and its preparation method. This material can quickly penetrate to the surface of the steel bars to convert rust into a dark brown protective layer, and can also be vapor-transferred to the surface of the steel bars to inhibit rusting again.

[0008] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0009] A migratory steel rust conversion material is obtained by mixing and stirring nano-rust conversion seed crystals with a penetrant and an emulsifier. The nano-rust conversion seed crystals have a three-layer coating structure, with nanomaterials as the crystal nucleus, an intermediate layer consisting of an activation product formed by the rust conversion component and the hydroxyl groups on the surface of the nanomaterials, and an outermost layer coating a mixture of migratory rust inhibitor components and organosilicon and its derivatives. The activation product in the intermediate layer is obtained by reacting the carboxyl groups in the rust conversion component with the hydroxyl groups on the surface of the nanomaterials, and forms an interpenetrating structure with the outermost component.

[0010] The method for preparing the nano-rust conversion seed crystals is as follows: a nanomaterial aqueous dispersion, organosilicon and its derivatives, migration rust-inhibiting components, rust conversion components and water are added sequentially to a reactor, and the mixture is stirred and reacted to obtain nano-rust conversion seed crystals;

[0011] The rust-converting component is selected from any one or a mixture of more than one organic carboxylic acid and inorganic acid;

[0012] The migration-inhibiting component is an organic amine compound;

[0013] The nanomaterials in the aqueous dispersion have a particle size of 1-100 nm, preferably 1-30 nm; the aqueous dispersion is selected from any one or a mixture of nano-titanium dioxide aqueous dispersion, nano-silica aqueous dispersion, nano-calcium carbonate aqueous dispersion, nano-alumina aqueous dispersion, nano-magnesium oxide aqueous dispersion, and nano-zinc oxide aqueous dispersion.

[0014] Furthermore, the reaction conditions in the preparation method of the nano-rust conversion seed crystals of the present invention are: reaction temperature of 30-60℃ and reaction time of 2-4h.

[0015] Furthermore, the mass percentage of each raw material component in this invention is as follows:

[0016]

[0017] The remainder is water.

[0018] The sum of the mass percentages of the above components is 100%;

[0019] The mass concentration of the aqueous dispersion of the nanomaterial is 5-40%.

[0020] Furthermore, the migration rust-inhibiting component of the present invention is selected from any one or a mixture of more than one of monoethanolamine, diethanolamine, triethanolamine, triisopropanolamine, N,N-dimethylethanolamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, diethanol monoisopropanolamine, monoethanol diisopropanolamine, and N,N-diethylethanolamine.

[0021] Furthermore, the rust-converting component of the present invention is any one or a mixture of more than one of malic acid, alginic acid, citric acid, tannic acid, polyphosphoric acid, phosphoric acid, tartaric acid, gallic acid, lactic acid, benzoic acid, salicylic acid, and caffeic acid.

[0022] Furthermore, the organosilicon and its derivatives described in this invention are selected from any one or more of γ-aminopropyltriethoxysilane, 3-aminopropyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, dodecyltriethoxysilane, isobutyltriethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, mercaptopropyltrimethoxysilane, 3-[(2,3)-epoxypropoxy]propylmethyldimethoxysilane, n-octyltrimethoxysilane, and n-hexyltrimethoxysilane.

[0023] Furthermore, the penetrant of the present invention is selected from any one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, octyl alcohol polyoxyethylene ether, nonylphenol polyoxyethylene ether, hexadecyltrimethylammonium bromide, ethanol, isopropanol, diglyceride, and acetone.

[0024] Furthermore, the emulsifier of the present invention is selected from any one or more of sodium stearate, N-dodecyl dimethylamine, tributylphenol polyoxyethylene ether, benzyl dimethylphenol polyoxyethylene ether, phenylethyl naphthol polyoxyethylene ether, lauryl polyoxyethylene ether, isooctyl polyoxyethylene ether, octadecyl polyoxyethylene ether, sorbitan fatty acid ester, and polyoxyethylene stearate.

[0025] Furthermore, the present invention also provides a method for preparing the above-mentioned migratory steel rust conversion material, which specifically includes the following: adding nano-rust conversion seed crystals, penetrant and emulsifier sequentially to a reactor, mixing and stirring to react, and obtaining the migratory steel rust conversion material after stirring is completed;

[0026] The reaction conditions are as follows: reaction temperature 30-80℃, stirring speed 300-1000 r / min, and reaction time 3-10 h.

[0027] The organosilicon and its derivatives described in this invention can form silane polymers near the hydration products during the hydration of cementitious materials in concrete, thereby increasing the density of the concrete. Furthermore, organosilicon molecules undergo a dehydration reaction with silanol groups in the concrete, forming a directionally aligned organosiloxane aqueous film within the concrete and on the surface of capillary pores, giving the concrete hydrophobic properties. In addition, nanomaterials possess four major effects: size, surface, macroscopic quantum tunneling, and interface. When incorporated into concrete, they can not only fill gaps in the concrete and improve its porosity, but also reduce ion transport.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] (1) The migratory steel rust conversion material prepared by the present invention can be directly coated on the metal surface or directly coated on the surface of existing concrete structure, avoiding the traditional rust conversion material from chiseling open the concrete protective layer to expose the steel bar. The construction process is simple and easy to operate, and it has the functions of inhibiting ion transport and good hydrophobicity.

[0030] (2) When the migratory steel rust conversion material prepared by the present invention is applied to the surface of steel bars, the intermediate layer component of the nano rust conversion seed with the interpenetrating structure reacts directly with the rust products and gradually converts the rust products into a blackish-brown protective layer. At the same time, the nano rust conversion seed is also gradually released. The released rust-inhibiting groups can further prevent the steel bars from further rusting or secondary rusting. The released organosilicon is adsorbed on the surface of the steel bars, giving the steel bars hydrophobic properties.

[0031] (3) If the migratory steel rust conversion material prepared by the present invention is applied to the concrete surface, the organosilicon molecules react with the silanol groups in the concrete, making the concrete hydrophobic. The nano rust conversion seeds gradually release rust conversion substances that penetrate into the concrete and convert the rusted steel bars in the concrete into a black protective film in situ. In addition, the released rust-inhibiting groups and gas-phase rust-inhibiting substances can further prevent the steel bars from further rusting or secondary rusting.

[0032] (4) In this invention, a solution-stable migratory steel rust conversion material is obtained by preparing nano rust conversion seed crystals. The preparation process is simple, convenient, and easy to produce. Detailed Implementation

[0033] The present invention will now be described in detail with reference to specific embodiments.

[0034] Example 1

[0035] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0036] (1) Add 5g of 30nm titanium dioxide dispersion, 0.1g of 3-aminopropyltriethoxysilane, 10g of N,N-dimethylethanolamine, 15g of malic acid and 59.9g of water to the reactor in sequence, set the temperature to 30℃, and stir for 2h to finish the reaction to obtain nano rust conversion seed crystals;

[0037] (2) In the nano rust conversion seed reactor prepared in step (1), 5g sodium dodecyl sulfate and 5g sodium stearate are added sequentially, stirred evenly, and the reaction temperature is set to 80℃, the stirring speed is 300r / min, and the migratory steel rust conversion material is obtained after stirring for 8h. This migratory steel rust conversion material is denoted as M1.

[0038] Example 2

[0039] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0040] (1) Add 1g of 15nm nano calcium carbonate dispersion, 5g of isobutyltriethoxysilane, 10g of tetraethylenepentamine, 15g of tannic acid and 77.9g of water to the reactor in sequence, and set the temperature to 40℃. After stirring for 4h, the reaction is completed and nano rust conversion seed crystals can be obtained.

[0041] (2) In the nano rust conversion seed reactor prepared in step (1), 0.1g isopropanol and 1g lauryl alcohol polyoxyethylene ether are added sequentially, stirred evenly, and the reaction temperature is set to 60℃, the stirring speed is 1000r / min, and the migratory steel rust conversion material is obtained after stirring for 6h. This migratory steel rust conversion material is denoted as M2.

[0042] Example 3

[0043] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0044] (1) Add 10g of 10nm nano alumina dispersion, 1g of n-hexyltrimethoxysilane, 10g of triethylenetetramine, 5g of benzoic acid and 68g of water to the reactor in sequence, and set the temperature to 50℃. After stirring for 3h, the reaction ends and nano rust conversion seed crystals can be obtained.

[0045] (2) In the nano rust conversion seed reactor prepared in step (1), 5g of acetone and 1g of isooctyl polyoxyethylene ether are added sequentially, stirred evenly, and the reaction temperature is set to 40℃, the stirring speed is 500r / min, and the migratory steel rust conversion material is obtained after stirring for 3h. This migratory steel rust conversion material is denoted as M3.

[0046] Example 4

[0047] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0048] (1) Add 5g of 20nm nano zinc oxide dispersion, 5g of dodecyltriethoxysilane, 5g of diethanolamine, 10g of gallic acid and 70g of water to the reactor in sequence, set the temperature to 60℃, and stir for 2h to finish the reaction to obtain nano rust conversion seed crystals.

[0049] (2) In the nano rust conversion seed reactor prepared in step (1), 2g of diglyceride and 3g of dehydrated sorbitan fatty acid ester are added sequentially, stirred evenly, and the reaction temperature is set to 70℃, the stirring speed is 800r / min, and the migratory steel rust conversion material is obtained after stirring for 10h. This migratory steel rust conversion material is denoted as M4.

[0050] Example 5

[0051] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0052] (1) Add 10g of 1nm nano magnesium oxide dispersion, 3g of vinyltrimethoxysilane, 3g of N,N-diethylethanolamine, 5g of citric acid and 76g of water to the reactor in sequence, set the temperature to 35℃, and stir for 4h to finish the reaction to obtain nano rust conversion seed crystals.

[0053] (2) In the nano rust conversion seed reactor prepared in step (1), 1g of octyl alcohol polyoxyethylene ether and 2g of tributylphenol polyoxyethylene ether are added sequentially, stirred evenly, and the reaction temperature is set to 30℃, the stirring speed is 500r / min, and the migratory steel rust conversion material is obtained after stirring for 7h. This migratory steel rust conversion material is denoted as M5.

[0054] Example 6

[0055] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0056] (1) Add 3g of 5nm nano alumina dispersion, 5g of mercaptopropyltrimethoxysilane, 5g of monoethanol diisopropanolamine, 10g of phosphoric acid and 69g of water to the reactor in sequence, set the temperature to 45℃, and stir for 2 hours to finish the reaction to obtain nano rust conversion seed crystals.

[0057] (2) In the nano rust conversion seed reactor prepared in step (1), 5g of cetyltrimethylammonium bromide, 1.5g of phenylethylnaphthol polyoxyethylene ether and 1.5g of N-dodecyldimethylamine were added in sequence, stirred evenly, and the reaction temperature was set to 50℃ and the stirring speed was 700r / min. After stirring for 5h, the migratory steel rust conversion material was obtained. This migratory steel rust conversion material was denoted as M6.

[0058] Comparative Example 1

[0059] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0060] (1) Add 5g of 20nm nano zinc oxide dispersion, 5g of dodecyltriethoxysilane, 5g of diethanolamine and 80g of water to the reactor in sequence, set the temperature to 60℃, and stir for 2h to finish the reaction to obtain nano rust conversion seed crystals.

[0061] (2) In the nano rust conversion seed reactor prepared in step (1), 2g of diglyceride and 3g of dehydrated sorbitan fatty acid ester are added sequentially, stirred evenly, and the reaction temperature is set to 70℃, the stirring speed is 800r / min, and the migratory steel rust conversion material is obtained after stirring for 10h. This migratory steel rust conversion material is denoted as R1.

[0062] Comparative Example 2

[0063] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0064] (1) Add 5g of 20nm nano zinc oxide dispersion, 5g of dodecyltriethoxysilane, 10g of gallic acid and 75g of water to the reactor in sequence, set the temperature to 60℃, and stir for 2h to finish the reaction to obtain nano rust conversion seed crystals.

[0065] (2) In the nano rust conversion seed reactor prepared in step (1), 2g of diglyceride and 3g of dehydrated sorbitan fatty acid ester are added sequentially, stirred evenly, and the reaction temperature is set to 70℃, the stirring speed is 800r / min, and the migratory steel rust conversion material is obtained after stirring for 10h. This migratory steel rust conversion material is denoted as R2.

[0066] Comparative Example 3

[0067] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0068] (1) Add 5g dodecyltriethoxysilane, 5g diethanolamine, 10g gallic acid and 75g water to the reactor in sequence, set the temperature to 60℃, and stir for 2 hours to finish the reaction to obtain nano rust conversion seed crystals.

[0069] (2) In the nano rust conversion seed reactor prepared in step (1), 2g of diglyceride and 3g of dehydrated sorbitan fatty acid ester are added sequentially, stirred evenly, and the reaction temperature is set to 70℃, the stirring speed is 800r / min, and the migratory steel rust conversion material is obtained after stirring for 10h. This migratory steel rust conversion material is denoted as R3.

[0070] Comparative Example 4

[0071] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0072] 5g of 20nm nano zinc oxide dispersion, 5g of dodecyltriethoxysilane, 5g of diethanolamine, 10g of gallic acid and 70g of water were added sequentially to the reactor. Then, 2g of diglyceride and 3g of dehydrated sorbitan fatty acid ester were added. After stirring for 10 hours, the migratory steel rust conversion material was obtained. This migratory steel rust conversion material was designated as R4.

[0073] Comparative Example 5

[0074] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0075] (1) Add 5g of 20nm nano zinc oxide dispersion, 5g of dodecyltriethoxysilane, 5g of diethanolamine, 10g of gallic acid and 70g of water to the reactor in sequence, and stir for 2 hours to finish the reaction.

[0076] (2) In step (1), add 2g of diglyceride and 3g of sorbitan fatty acid ester in sequence, stir evenly, set the reaction temperature to 70℃, the stirring speed to 800r / min, and stir for 10h to obtain the migratory steel rust conversion material. This migratory steel rust conversion material is denoted as R5.

[0077] Comparative Example 6

[0078] A method for preparing a migratory steel rust conversion material specifically includes the following:

[0079] (1) Add 5g of 20nm nano zinc oxide dispersion, 5g of diethanolamine, 10g of gallic acid and 75g of water to the reactor in sequence, set the temperature to 60℃, and stir for 2h to finish the reaction to obtain nano rust conversion seed crystals.

[0080] (2) In the nano rust conversion seed reactor prepared in step (1), 2g of diglyceride and 3g of dehydrated sorbitan fatty acid ester are added sequentially, stirred evenly, and the reaction temperature is set to 70℃, the stirring speed is 800r / min, and the migratory steel rust conversion material is obtained after stirring for 10h. This migratory steel rust conversion material is denoted as R6.

[0081] Performance testing

[0082] (I) Solution Stability

[0083] Samples from each embodiment and comparative example were poured into centrifuge tubes and tested using a TG16-WS high-speed centrifuge from Changsha Xiangzhi Centrifuge Instrument Co., Ltd. The rotation speed was set to 3000 r / min and the centrifugation time was set. After centrifugation, the solution layering was observed.

[0084] Table 1 Stability

[0085] Serial Number Layering after centrifugation for 10 minutes Layering after centrifugation for 30 minutes M1 No layering No layering M2 No layering No layering M3 No layering No layering M4 No layering No layering M5 No layering No layering M6 No layering No layering R1 Layering Layering R2 No layering Layering R3 Layering Layering R4 Layering Layering R5 Layering Layering R6 No layering Layering

[0086] The stability test results show that no stratification occurred in any of the examples, indicating that the prepared migratory steel rust conversion material has good stability. However, the comparative examples show that R3 showed stratification after centrifugation for 10 minutes, indicating that it has poor stability due to the absence of nanomaterials and the failure to form nano rust conversion seeds. R4 and R5 did not form nano rust conversion seeds, indicating poor solution stability. R1 showed stratification after centrifugation for 10 minutes, while R2 and R6 showed stratification after centrifugation for 30 minutes.

[0087] (II) Rust Conversion Effect

[0088] Uniformly rusted steel bars were used as the control group. The other groups had a migratory steel bar rust conversion material coated on their surfaces. The rusted areas and secondary rust were then observed. After each coating period, the steel bars were placed in an aqueous solution to test the corresponding electrochemical parameters, specifically the corrosion current density. A lower corrosion current density indicated a better rust conversion effect. The contact angle experiment was conducted using a DSA255 contact angle meter (KRUSS GmbH, Germany) 12 hours after coating the rusted steel bar surface. The results are shown in Table 2.

[0089] Table 2 Corrosion rate of steel bars in chloride-containing concrete simulation solution

[0090]

[0091] As shown in Table 2, compared with the blank group, the embodiments of the present invention can rapidly and significantly reduce the corrosion current density of steel bars within a short period of 1 hour, indicating that the migratory steel bar rust conversion material can efficiently and quickly carry out rust conversion, and the current density drops to 0.01 μA / cm² within 12 hours. 2 Within this range, it is also indicated that there was no secondary corrosion in the rusted area. However, comparative example R3 showed the worst effect, indicating that R3 did not form nano-rust conversion seeds, resulting in poor rust conversion. R1 and R2 also indicate that they did not form more stable nano-rust conversion seeds. Although their effects were slightly better than R3, they differed significantly from the examples. R4 and R5 also did not exhibit good rust conversion performance. After coating the rusted steel bar surface for 12 hours, the contact angles of examples M1-M6 increased significantly, all exceeding 100°, indicating good hydrophobic properties. In contrast, the contact angles of comparative examples R1-R5 were smaller, indicating poor hydrophobic properties. The contact angle of R6 was only 10.5°, indicating that it had virtually no hydrophobic properties on the steel bar surface.

[0092] The water absorption and hydrophobic properties of the hydrophobic and rust-inhibiting materials in the above examples were evaluated according to GB / T 50082 "Standard for Test Methods of Long-Term Performance and Durability of Ordinary Concrete". The W / C ratio of the concrete was 0.35, the cement was Conch PO.42.5 silicate cement, the sand was river sand, and the aggregate was basalt with a particle size range of 5-15 mm and 10-25 mm and a sand ratio of 40%. The uniformly rusted steel bars were embedded in the newly formed concrete test blocks, and the thickness of the steel bar protective layer was 25 mm. After 3 days, the standard cured concrete test blocks were taken out, and a migration-type steel bar rust conversion material was uniformly coated on the concrete surface. Before the test, the test blocks were soaked in an aqueous solution for 1 day and then the corrosion current density was tested. The results are shown in Table 3.

[0093] Table 3 Corrosion current density of steel reinforcement in concrete

[0094]

[0095]

[0096] The experimental results after 3 days of coating show that, with the addition of the migratory steel rust conversion materials from Examples M1 to M6, the corrosion current density decreased to 1.25 μA / cm³ after 3 days of coating. 2 The results indicate that the migratory steel rust conversion material can quickly penetrate to the surface of concrete steel bars and efficiently convert rust products. In contrast, the corrosion current density of comparative examples R1 to R6 decreased only slightly after 3 days of coating, indicating a poor conversion effect. Furthermore, there was no significant rust conversion effect after 28 days of coating.

[0097] (III) Water absorption and hydrophobicity properties of concrete

[0098] After the above standard curing for 3 days, the concrete test blocks were taken out. The blank group consisted of untreated concrete test blocks, while the others were coated with a migratory steel rust conversion material. After standing for 7 days, the contact angle and 30-minute water absorption rate of the coated surface were tested.

[0099] Table 4 Water absorption rate and contact angle

[0100]

[0101]

[0102] As shown in Table 4, the water absorption rate of the migratory steel rust conversion material of the present invention, after being coated on the concrete surface, was significantly lower than that of the control group after 30 minutes. This indicates that adding the migratory steel rust conversion material of the present invention to concrete can reduce water absorption, inhibit water absorption, and suppress ion transport. Furthermore, Table 4 also shows that the contact angles of M1-M6 are all above 120°, indicating that the migratory steel rust conversion material of the present invention, when coated on the concrete surface, can give the concrete good hydrophobic properties. In contrast, the contact angles of R1-R6 are smaller, and they do not provide good hydrophobic properties to the concrete, especially the comparative example R6 concrete, which has virtually no hydrophobic effect.

[0103] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A migrating rebar corrosion conversion material, characterized by: The migration type rust conversion material is obtained by mixing and stirring nano rust conversion seeds and a penetrating agent and an emulsifier; wherein the nano rust conversion seeds have a three-layer coating structure, the nano material is used as a crystal nucleus, the intermediate layer is an activated product formed by rust conversion components and hydroxyl groups on the surface of the nano material, and the outermost layer is a mixture of a migration rust prevention component and organosilicon and its derivatives; the activated product of the intermediate layer is obtained by the reaction of carboxyl groups in the rust conversion components and the hydroxyl groups on the surface of the nano material, and forms an interpenetrating structure with the components in the outermost layer; The preparation method of the nano rust conversion seeds comprises the following steps: sequentially adding a nano material water dispersion, organosilicon and its derivatives, a migration rust prevention component, rust conversion components and water into a reactor, and stirring and reacting to obtain the nano rust conversion seeds; The rust conversion components are selected from any one or more of organic carboxylic acids and inorganic acids; The migration rust prevention component is an organic amine compound; The nano material in the nano material water dispersion has a particle size of 1-100 nm; and the nano material water dispersion is selected from any one or more of nano titanium dioxide water dispersion, nano silicon dioxide water dispersion, nano calcium carbonate water dispersion, nano aluminum oxide water dispersion, nano magnesium oxide water dispersion and nano zinc oxide water dispersion.

2. The migrating rebar corrosion conversion material of claim 1, wherein, The nano material in the nano material water dispersion has a particle size of 1-30 nm.

3. The migrating rebar corrosion conversion material of claim 1, wherein, The reaction conditions in the preparation method of the nano rust conversion seeds are as follows: the reaction temperature is 30-60°C, and the reaction time is 2-4 h.

4. The migrating rebar corrosion conversion material of claim 1, wherein, The mass percentage of each raw material component is as follows: The balance is water, The sum of the mass percentages of the components is 100%; The mass concentration of the nano material water dispersion is 5-40%.

5. The migrating rebar corrosion conversion material of claim 1, wherein, The migration rust prevention component is selected from any one or more of monoethanolamine, diethanolamine, triethanolamine, triisopropanolamine, N,N-dimethylethanolamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, diethanol monoisopropanolamine, monoethanol diisopropanolamine and N,N-diethylethanolamine.

6. The migrating rebar corrosion conversion material of claim 1, wherein The rust conversion components are selected from any one or more of malic acid, alginic acid, citric acid, tannic acid, polyphosphoric acid, phosphoric acid, tartaric acid, gallic acid, lactic acid, benzoic acid, salicylic acid and coffee acid.

7. The migrating rebar corrosion conversion material of claim 1, wherein The organosilicon and its derivatives are selected from any one or more of γ-aminopropyl triethoxysilane, 3-aminopropyl triethoxysilane, N-(β-aminoethyl)-γ-aminopropyl trimethoxysilane, dodecyl triethoxysilane, isobutyl triethoxysilane, vinyl triethoxysilane, vinyl trimethoxysilane, mercaptopropyl trimethoxysilane, 3-[(2,3)-epoxypropoxy]propyl methyl dimethoxysilane, n-octyl trimethoxysilane and n-hexyl trimethoxysilane.

8. The migrating rebar corrosion conversion material of claim 1, wherein, The penetrating agent is selected from any one or more of sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, octyl alcohol polyoxyethylene ether, nonyl phenol polyoxyethylene ether, cetyl trimethyl ammonium bromide, ethanol, isopropanol, diethylene glycol ether and acetone.

9. The migrating rebar corrosion conversion material of claim 1, wherein, The emulsifier is selected from any one or more than one of sodium stearate, N-dodecyl dimethylamine, tributyl phenol polyoxyethylene ether, benzyl dimethyl phenol polyoxyethylene ether, phenylethyl naphthol polyoxyethylene ether, lauryl alcohol polyoxyethylene ether, isooctyl polyoxyethylene ether, octadecanol polyoxyethylene ether, sorbitan fatty acid ester, and stearic acid polyoxyethylene ester.

10. A method of producing the migrating rebar corrosion conversion material according to any one of claims 1 to 9, characterized by, Specifically comprising the following: sequentially adding nano-rust conversion seeds, a penetrating agent and an emulsifier in a reactor, mixing and stirring to react, and obtaining the migration type steel bar rust conversion material after the stirring is completed. The reaction conditions are as follows: the reaction temperature is 30-80 DEG C, the stirring speed is 300-1000 r / min, and the reaction time is 3-10 h.

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