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CN-121975360-A - Water-based inorganic coating for concrete structure and preparation method thereof

CN121975360ACN 121975360 ACN121975360 ACN 121975360ACN-121975360-A

Abstract

The application discloses a water-based inorganic coating for a concrete structure and a preparation method thereof. The application provides a water-based inorganic coating for a concrete structure, which comprises a component A and a component B, wherein the component A comprises, by weight, 20-30 parts of modified water glass, 8-12 parts of fine filler, 6-10 parts of ultrafine filler, 0.5-1 part of fluorosilicate, 50-60 parts of silicate cement, 2-4 parts of a retarding type water reducer and 25-35 parts of water, and the component B comprises, by weight, 30-40 parts of polybutadiene type silane end-capped polyurethane prepolymer, 50-60 parts of silicate cement, 18-24 parts of nano titanium dioxide, 1-1.5 parts of a polycarboxylic acid water reducer and 35-45 parts of water. On the other hand, the application also provides a preparation method of the water-based inorganic coating for the concrete structure. The application has excellent deep penetration crystallization performance and strong waterproof performance and impermeability.

Inventors

  • ZHOU HENG
  • ZHENG JIANG
  • LI JUN
  • LIU WULIN

Assignees

  • 湖北黄鹰岩新材料科技有限公司

Dates

Publication Date
20260505
Application Date
20260407

Claims (9)

  1. 1. The water-based inorganic coating for the concrete structure is characterized by comprising, by mass, 20-30 parts of modified water glass, 8-12 parts of micron-sized fine fillers, 6-10 parts of nano-sized ultrafine fillers, 0.5-1 part of fluorosilicate, 50-60 parts of Portland cement, 2-4 parts of retarded water reducer and 25-35 parts of water, wherein the weight parts of the components B comprise 30-40 parts of polybutadiene-type silane-terminated polyurethane prepolymer, 50-60 parts of Portland cement, 18-24 parts of nano titanium dioxide, 1-1.5 parts of polycarboxylic water reducer and 35-45 parts of water, the modified water glass is sodium lithium water glass, the mass ratio of sodium silicate to lithium silicate is 1-4:1, and the nano-sized ultrafine fillers are nano kaolin.
  2. 2. The aqueous inorganic coating for concrete structures according to claim 1, wherein the raw materials of the component a further comprise 8-10 parts of basalt short fibers, the length of the basalt short fibers is 0.1-0.5 mm, and the fiber diameter is 7-14 μm.
  3. 3. The aqueous inorganic coating for concrete structures according to claim 2, wherein the mass ratio of sodium silicate to lithium silicate in the modified water glass is 2-3:1.
  4. 4. The aqueous inorganic coating for concrete structures according to claim 1, wherein the fine filler of micrometer size is selected from exhaust glass micropowder.
  5. 5. The aqueous inorganic coating for concrete structures according to claim 1, wherein the preparation of the polybutadiene-type silane-terminated polyurethane prepolymer comprises the steps of: S1-1, fully mixing monoisocyanate grafted silane and hydroxyl-terminated polybutadiene according to a molar ratio of 1:1 to prepare a mixture; s1-2, adding dibutyl tin dilaurate accounting for 0.08% of the total mass of the mixture into the mixture obtained in the step S1-1, fully mixing, heating to 60-65 ℃, reacting for 4-4.5 h, and cooling to obtain the polybutadiene silane end-capped polyurethane prepolymer.
  6. 6. The aqueous inorganic coating for concrete structures according to claim 5, wherein in the step S1-1, 3-isocyanatopropyl trimethoxy silicon is selected as the monoisocyanate grafted silane.
  7. 7. The aqueous inorganic coating for concrete structures according to claim 5, wherein in the step S1-1, the hydroxyl-terminated polybutadiene is hydrogenated hydroxyl-terminated polybutadiene.
  8. 8. The aqueous inorganic coating for concrete structures according to claim 7, wherein the preparation of the hydrogenated hydroxyl-terminated polybutadiene comprises the steps of: Sa, dissolving hydroxyl-terminated polybutadiene in cyclohexane to prepare a solution with the concentration of 5%, adding a mixed catalyst prepared by copper chromite powder and copper oxide powder with the mass ratio of 1:1 into a pressure reaction container; Sb, continuously introducing hydrogen into a container, maintaining the pressure in the reaction container at 1.2-1.4 MPa, heating to 55-60 ℃ for reaction for 2h, heating to 75-80 ℃ for reaction for 6h, and filtering out a mixed catalyst to obtain a reaction mixed solution; and (3) steaming the reaction mixture at the temperature of 80-85 ℃ in a rotary way, and steaming to remove the cyclohexane solvent to obtain the hydrogenated hydroxyl-terminated polybutadiene.
  9. 9. A method for preparing the aqueous inorganic coating for concrete structures according to any one of claims 1 to 8, characterized by comprising the following steps: s1, preparing polybutadiene silane end-capped polyurethane prepolymer; s2, mixing the raw materials of the component A according to the formula amount, shearing and stirring at a high speed of 2000-2500 rpm for more than 30min, and standing for defoaming to obtain the component A; S3, mixing silicate cement, nano titanium dioxide and a polycarboxylic acid water reducer according to the formula amount, adding water according to the formula amount, fully stirring and mixing to prepare slurry, adding polybutadiene silane end-capped polyurethane prepolymer into the slurry, shearing and stirring at a high speed of 2000-2500 rpm for more than 30min, and standing for defoaming to prepare the component B.

Description

Water-based inorganic coating for concrete structure and preparation method thereof Technical Field The application relates to the technical field of waterproof materials, in particular to a water-based inorganic coating for a concrete structure and a preparation method thereof. Background Concrete is the most commonly used building material in present buildings, and is widely applied to buildings, bridges, tunnels, culverts and the like. The concrete of these buildings is exposed to the outside environment for a long period of time, and is susceptible to damage caused by chemical reactions or physical actions with certain corrosive media in the environment. According to the prior studies, water, oxygen, carbon dioxide and chloride ions in the environment are main factors causing corrosion damage of concrete, and water is a key core factor. Under the action of moisture, carbon dioxide easily permeates into the concrete to form carbonic acid, so that the concrete is carbonized to cause corrosion damage of the concrete, the corroded and damaged concrete cannot effectively protect the internal steel bars, and under the condition of moisture and oxygen permeation, electrochemical reaction of the steel bars can be initiated to cause corrosion of the steel bars. Therefore, waterproofing of concrete buildings is a key to ensure durability thereof. At present, the main means for concrete waterproofing is to construct a waterproof coating layer on the surface of concrete, and the existing waterproof coating is divided into two types, namely organic coating and inorganic coating. The organic waterproof coating has flexibility after film formation, is not easy to crack after long-term use, has excellent water blocking effect after film formation, and is wide in application. However, the hydrophobic nature of the organic waterproof paint causes poor compatibility with concrete, and the heat expansion coefficient and the cold contraction coefficient of the organic waterproof paint and the concrete have great difference, so that the service life is generally shorter, and the problems of bulge, falling and the like are easy to occur. The inorganic waterproof coating takes the inorganic gel material as the main component, has good compatibility with concrete, and has the advantages of environmental protection, weather resistance and the like. In particular to a permeable crystallization type inorganic waterproof coating taking silicate gel materials as main components, which can permeate into concrete from concrete gaps to crystallize, can deeply repair damaged concrete, and is widely applied to repair and waterproof of concrete buildings. The existing permeable crystallization type inorganic waterproof coating is generally high in rigidity and easy to crack after long-term use. Although the problem of easy cracking can be relieved to a certain extent by mixing the anti-cracking fiber, the existing permeable crystalline inorganic waterproof coating also has the problems of insufficient penetration depth, insufficient overall waterproof performance, poor impermeability and the like. Disclosure of Invention In order to solve at least one technical problem, the application provides a water-based inorganic coating for a concrete structure and a preparation method thereof, wherein the water-based inorganic coating has relatively low cost, excellent deep penetration crystallization performance and strong waterproof performance and impermeability. The application provides a water-based inorganic coating for a concrete structure, which comprises, by mass, 20-30 parts of modified water glass, 8-12 parts of micron-sized fine fillers, 6-10 parts of nano-sized ultrafine fillers, 0.5-1 part of fluorosilicate, 50-60 parts of silicate cement, 2-4 parts of retarded water reducer and 25-35 parts of water, wherein the weight parts of the raw materials of the component B comprise 30-40 parts of polybutadiene-type silane-terminated polyurethane prepolymer, 50-60 parts of silicate cement, 18-24 parts of nano titanium dioxide, 1-1.5 parts of polycarboxylic acid water reducer and 35-45 parts of water, the mass ratio of sodium silicate to lithium silicate is 2-3:1, and the nano-sized ultrafine fillers are nano kaolin. Optionally, the raw materials of the component A further comprise 8-10 parts of basalt short fibers, the length of the basalt short fibers is 0.1-0.5 mm, and the fiber diameter is 7-14 mu m. Optionally, in the modified water glass, the mass ratio of sodium silicate to lithium silicate is 2-3:1. Optionally, the micron-sized fine filler is waste gas glass micropowder. Optionally, the preparation of the polybutadiene silane end capped polyurethane prepolymer comprises the following steps: S1-1, fully mixing monoisocyanate grafted silane and hydroxyl-terminated polybutadiene according to a molar ratio of 1:1 to prepare a mixture; s1-2, adding dibutyl tin dilaurate accounting for 0.08% of the total mass of the mixture into the mixture ob