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CN-122011826-A - Nano silicon dioxide filler, nano composite anticorrosive paint containing nano silicon dioxide filler and preparation method of anticorrosive paint

CN122011826ACN 122011826 ACN122011826 ACN 122011826ACN-122011826-A

Abstract

The invention discloses a nano silicon dioxide filler, a nano composite anticorrosive paint containing the nano silicon dioxide filler and a preparation method of the anticorrosive paint, wherein the nano silicon dioxide filler is prepared by a low-temperature molten salt method and is treated by a surface modifier; the low-temperature molten salt method comprises the steps of preparing a molten salt medium, mixing a silicon source, the molten salt medium and a precipitator to obtain a reaction precursor, reacting the reaction precursor at 150-350 ℃ for 2-24 hours to generate nano silicon dioxide, cooling a reaction product, dissolving and removing the soluble salt, separating and drying to obtain the nano silicon dioxide filler. The invention aims to construct a physical shielding, cathodic protection and interface enhanced multiple synergistic anti-corrosion system, thereby remarkably improving the corrosion resistance, mechanical property and storage stability of the coating and obtaining a technical scheme suitable for industrial production.

Inventors

  • ZHAN WEN
  • SHI TONG
  • HU XINGLONG
  • Shen Erbo
  • LI HONGJUN
  • YANG RUXIAN
  • SUN YUQIU
  • LI JIAZHI
  • ZHANG SI
  • TANG KAI

Assignees

  • 中交二航武汉港湾新材料有限公司
  • 中交武汉港湾工程设计研究院有限公司

Dates

Publication Date
20260512
Application Date
20251231

Claims (9)

  1. 1. The nano silica filler for the anticorrosive paint is characterized by being prepared by a low-temperature molten salt method and treated by a surface modifier, wherein the low-temperature molten salt method comprises the following steps of: s1, preparing a molten salt medium, wherein the molten salt medium consists of one or more soluble inorganic salts; S2, mixing a silicon source, the molten salt medium and a precipitator to obtain a reaction precursor; s3, reacting the reaction precursor for 2-24 hours at 150-350 ℃ to generate nano silicon dioxide; And S4, cooling the reaction product, dissolving and removing soluble salt, separating and drying to obtain the nano silicon dioxide filler.
  2. 2. The nano-silica filler of claim 1, wherein the surface modifier is a silane coupling agent.
  3. 3. The nano silica filler according to claim 1 or 2, wherein the specific surface area of the nano silica is 200 to 800 m2/g, the average particle diameter is 10 to 100 nm, and the variation coefficient of the particle diameter distribution is <20%.
  4. 4. A nanocomposite anticorrosive coating comprising a nanosilica filler according to any one of claims 1 to 3, a film-forming resin and an anticorrosive pigment.
  5. 5. The nanocomposite anticorrosive paint according to claim 4, wherein the film-forming resin is 20-40 parts by mass, the anticorrosive pigment is 20-60 parts by mass, and the nano silica filler is 1-10 parts by mass.
  6. 6. The nanocomposite, corrosion resistant coating according to claim 4 or 5, wherein said film forming resin is an epoxy resin and said corrosion resistant pigment is zinc powder.
  7. 7. The nanocomposite, corrosion resistant coating according to any one of claims 4 to 6, wherein the coating is a two-component system comprising a component a and a component B; The component A comprises the film-forming resin, the anti-corrosion pigment, the nano silicon dioxide filler, a solvent and an auxiliary agent, wherein the auxiliary agent comprises a dispersing agent, a defoaming agent and a leveling agent; the component B is a curing agent matched with the film-forming resin.
  8. 8. A method of preparing the nanocomposite anticorrosive coating according to claim 7, wherein the preparation of the a component comprises the steps of: 1) Mixing nano silicon dioxide filler, solvent, dispersant and part of film-forming resin, and pre-dispersing; 2) Grinding the pre-dispersed slurry until the fineness is less than or equal to 30 mu m; 3) Adding the rest film-forming resin, the anti-corrosion pigment and other auxiliary agents into the ground slurry, and uniformly stirring to obtain a coating A component; before construction, the component A and the component B are mixed and cured for use.
  9. 9. The method according to claim 8, wherein the pre-dispersing in the step 1) is performed by stirring at a high speed of 1000-1500 r/min for 15-30 minutes, and the grinding in the step 2) is performed by sand milling or ball milling.

Description

Nano silicon dioxide filler, nano composite anticorrosive paint containing nano silicon dioxide filler and preparation method of anticorrosive paint Technical Field The invention relates to the technical field of anticorrosive paint. More particularly, the invention relates to a nano silicon dioxide filler, a nano composite anticorrosive paint containing the nano silicon dioxide filler and a preparation method of the anticorrosive paint. Background Metal corrosion is a global economic problem, and in marine environments, the corrosion rate of steel structures can reach 0.1-0.3 mm/year, which seriously threatens engineering safety. The coating protection is used as the most economical and effective anti-corrosion means, and the service life of the metal structure is directly determined by the performance of the coating. The main current anticorrosive paint system mainly comprises 1 an epoxy zinc-rich primer system, a polyurethane paint system, a fluorocarbon paint system, a high-cost and severe construction requirement, wherein the epoxy zinc-rich primer system relies on the cathodic protection effect of zinc powder, but has the problems of large zinc powder consumption, over 50 percent in general, easy embrittlement of a coating, high zinc powder consumption and the like, and 2 the polyurethane paint system has excellent weather resistance and insufficient chemical resistance. The specific defects in the prior art are 1, the compactness of the coating is insufficient, the porosity of the traditional coating is usually 5-10%, the water vapor permeability reaches 10 -9~10-11 g/(m2.s.Pa), and the corrosive medium is difficult to effectively block. 2. The nanomaterial application bottleneck is that although there are already nanomaterialsThe application of the nano-powder in the anticorrosive paint reports that commercial nano-powder is adopted, so that the problems of serious agglomeration, uneven dispersion, poor compatibility with resin and the like exist, and the improvement of practical performance is limited. 3. The function is single, the existing paint is mostly dependent on a single corrosion prevention mechanism, and the synergistic effect is lacked. Therefore, developing a novel coating system with high compactness, strong adhesive force and long-acting corrosion resistance is a technical problem to be solved in the field. Disclosure of Invention The invention aims to provide a nano silicon dioxide filler synthesized and modified by a low-temperature molten salt method, so as to solve the technical bottlenecks of easy agglomeration, poor dispersion and limited performance improvement of commercial nano materials in anticorrosive paint. The invention further provides a nano composite anticorrosive paint containing the filler and a preparation method thereof, and aims to construct a physical shielding, cathodic protection and interface enhancement multi-synergistic anticorrosive system, so that the corrosion resistance, mechanical property and storage stability of the coating are obviously improved, and a technical scheme suitable for industrial production is obtained. The invention solves the technical problem by adopting the technical scheme that the nano silicon dioxide filler for the anti-corrosion coating is prepared by a low-temperature molten salt method and is treated by a surface modifier, wherein the low-temperature molten salt method comprises the following steps of: s1, preparing a molten salt medium, wherein the molten salt medium consists of one or more soluble inorganic salts; Preferably, in the step S1, the soluble inorganic salt comprises at least one of nitrate, chloride and acetate, and more preferably, the molten salt medium is a mixture of lithium nitrate and potassium nitrate according to the mass ratio of (40-60) (60-40). S2, mixing a silicon source, the molten salt medium and a precipitator to obtain a reaction precursor; preferably, in step S2, the silicon source is at least one of methyl orthosilicate, ethyl orthosilicate, and sodium silicate. Preferably, in step S2, the precipitating agent is a compound that can decompose under heating to produce an alkaline substance, preferably urea or hexamethylenetetramine. Preferably, in the step S2, the mass ratio of the silicon source, the molten salt medium and the precipitant is 1 (2-10): 0.5-3. S3, reacting the reaction precursor for 2-24 hours at 150-350 ℃ to generate nano silicon dioxide; preferably, in the step S3, the reaction temperature is 180 ℃ to 250 ℃ and the reaction time is 4 to 12 hours. Preferably, in step S3, the reaction precursor mixture is placed in a closed reactor for reaction, and the closed reactor is a ceramic crucible with a cover or a stainless steel reaction kettle with a polytetrafluoroethylene lining. And S4, cooling the reaction product, dissolving and removing soluble salt, separating and drying to obtain the nano silicon dioxide filler. As a further scheme of the invention, the surface modifier is a sil