Modified silica sol, preparation method and catalyst slurry thereof
By preparing modified silica sol and catalyst slurry, the environmental hazards of traditional coatings and the performance defects of nano-SiO2 were solved, thereby improving the stability and compatibility of coatings and reducing the powdering rate.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-04-03
AI Technical Summary
Traditional solvent-based coatings are harmful to the environment and waste resources. The performance defects of nano-SiO2 in coatings need to be modified to improve performance.
Modified silica sol was prepared by mixing silica sol with an ionic liquid, adding a silane coupling agent and adjusting the pH value. This modified silica sol was then used to prepare a catalyst slurry, which included modified silica sol, deionized water, catalyst and dispersant.
It improves the stability of silica sol and its compatibility with other materials, enhances the dispersion uniformity and adhesion of coatings, and reduces powder shedding.
Smart Images
Figure CN121775829A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of inorganic nanomaterials technology, specifically to a modified silica sol, its preparation method, and its catalyst slurry. Background Technology
[0002] Traditional solvent-based coatings cause enormous damage and harm to the ecological environment and human health, and also waste resources and energy. With increasing attention to environmental pollution and the improvement of living standards in my country, people have high hopes for environmentally friendly water-based coatings. Water-based coatings have excellent advantages such as environmental friendliness, good film-forming properties, and high weather resistance, and have been widely used in architectural decoration, wood coatings, and metal coatings.
[0003] Silica sol is an aqueous solution of SiO2, a green material. It is a colloidal solution of nanoscale high-molecular inorganic polysilicic acid with water as the dispersion medium. It is a thermodynamically unstable system that relies on charge or other stabilizers for dispersion. During the composite process, changes in environmental conditions may cause flocculation, agglomeration or gelation.
[0004] Currently, nano-SiO2 has been added to coatings as an additive, but due to its inherent performance defects, it needs to be modified to improve various aspects of the coating's properties. Therefore, it is necessary to conduct research on silica sol and develop novel modified silica sols, which is crucial for the industrial production and application of coatings. Summary of the Invention
[0005] In view of the deficiencies in the prior art, the purpose of this invention is to provide a modified silica sol, a preparation method thereof, and a catalyst slurry thereof.
[0006] A method for preparing a modified silica sol according to the present invention is characterized by comprising: S1, mix silica sol and ionic liquid at a mass ratio of 1:0.001-0.02, and stir at 200-600 rpm for 30-90 min at a temperature of 30-60℃ to obtain a preliminary mixture; S2, add a predetermined amount of silane coupling agent to the silica sol in the initial mixture, wherein the silane coupling agent and the silica sol in the initial mixture are mixed at a mass ratio of 1:0.01-0.1, and stirred at a temperature of 30-60℃ and a speed of 200-400rpm for 60-120min to obtain the intermediate mixture; S3. Add a pH adjuster to the intermediate mixture to adjust the pH value of the solution to 7-9, and then obtain the modified silica sol.
[0007] In some embodiments, in step S1, the solid content of the silica sol is 20%-50%.
[0008] In some embodiments, in step S1, the ionic liquid is a quaternary ammonium ionic liquid or an imidazole ionic liquid.
[0009] In some embodiments, in step S1, the ionic liquid is one of 1-butyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium tetrafluoroborate, 2-hydroxyethyltrimethylammonium acetate, and tetrabutylammonium carboxylate.
[0010] In some embodiments, in step S2, the silane coupling agent is any one of γ-aminopropyltriethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, and vinyltrimethoxysilane.
[0011] In some embodiments, in step S3, the pH adjustment reagent is hydrochloric acid or ammonia.
[0012] The present invention also provides a modified silica sol, obtained by the preparation method of the modified silica sol.
[0013] The present invention also provides a catalyst slurry, comprising the following components by weight percentage: Modified silica sol 10-40% 30-50% deionized water catalyst 1-10% Dispersant 0.1-1%.
[0014] In some embodiments, the catalyst is one of sodium vanadate, ammonium molybdate, and cobalt molybdate.
[0015] In some embodiments, the dispersant is one of sodium polyacrylate, hexadecyltrimethylammonium bromide, and alkylphenol polyoxyethylene ether.
[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. The method for preparing modified silica sol according to the present invention introduces an ionic liquid with diverse functional groups. The abundant hydroxyl, amino, and carboxyl groups in the ionic liquid and the silanol groups in the silica sol can jointly enhance the adhesion effect of the silica sol. The ionized anions and cations in the ionic liquid increase the electron cloud density on the surface of the silica sol particles, thereby improving the stability of the silica sol. At the same time, the added silane coupling agent can further enrich the number of silanol groups and improve the compatibility of the silica sol with other inorganic materials.
[0017] 2. The catalyst slurry prepared by the modified silica sol in this invention can be used for coating or modifying inorganic materials, which can effectively improve the dispersion uniformity and adhesion of the materials and reduce the powder loss rate of the materials. Attached Figure Description
[0018] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a magnified view of a portion of the structure of the catalyst slurry of the present invention applied to glass fiber mat. Detailed Implementation
[0019] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.
[0020] Example 1 1 kg of silica sol with a solid content of 30% and a particle size of approximately 10 nm was placed in a beaker. 1 g of 1-ethyl-3-methylimidazolium tetrafluoroborate was added to the beaker, and a magnetic stirrer was turned on. The mixture was stirred at 300 rpm for 60 min at 30°C. 10 g of vinyltrimethoxysilane was then weighed and added to the mixture, and stirring was continued at 300 rpm for 60 min at 30°C. The pH of the mixture was adjusted to 7 using a 1 mol / L hydrochloric acid solution, with continuous stirring throughout the process, to obtain the modified silica sol.
[0021] Example 2 1 kg of silica sol with a solid content of 30% and a particle size of approximately 10 nm was placed in a beaker. 10 g of 1-ethyl-3-methylimidazolium tetrafluoroborate was added to the beaker, and a magnetic stirrer was turned on. The mixture was stirred at 300 rpm for 60 min at 30°C. 50 g of vinyltrimethoxysilane was then weighed and added to the mixture, and stirring was continued at 300 rpm for 60 min at 30°C. The pH of the mixture was adjusted to 8 using a 1 mol / L hydrochloric acid solution, with continuous stirring throughout the process, until the modified silica sol was obtained.
[0022] Example 3 1 kg of silica sol with a solid content of 30% and a particle size of approximately 10 nm was placed in a beaker. 20 g of 1-ethyl-3-methylimidazolium tetrafluoroborate was added to the beaker, and a magnetic stirrer was turned on. The mixture was stirred at 300 rpm for 60 min at 30°C. 100 g of vinyltrimethoxysilane was then weighed and added to the mixture, and stirring was continued at 300 rpm for another 60 min at 30°C. The pH of the mixture was adjusted to 7 using a 1 mol / L hydrochloric acid solution, with continuous stirring throughout the process, until the modified silica sol was obtained.
[0023] Application Example 1 Prepare 1 kg of deionized water. Weigh 300 g of the modified silica sol prepared in the above example and add it to the deionized water. Stir for 30 min, then add 5 g of sodium vanadate and stir for 10 min. Add 1.5 g of sodium polyacrylate and continue stirring for 60 min to obtain the catalyst slurry. Take a glass fiber mat of appropriate size, immerse it in the above slurry, and after it is fully soaked, remove the glass fiber mat, drain off the excess slurry, and dry it in an 80℃ oven to obtain the catalyst glass fiber mat. See [link to relevant documentation]. Figure 1 Here is a magnified view of a portion of it.
[0024] Application Example 2 Prepare 1 kg of deionized water, weigh 400 g of the modified silica sol prepared in the above example, add it to the deionized water and stir. After stirring for 30 min, add 10 g of sodium vanadate and stir for 10 min. Then add 5 g of hexadecyltrimethylammonium bromide and continue stirring for 60 min to obtain the catalyst slurry. Take a glass fiber mat of appropriate size, immerse it in the above slurry, and after it is fully soaked, take out the glass fiber mat, drain off the excess slurry, and dry it in an 80℃ oven to obtain the catalyst glass fiber mat.
[0025] Application Example 3 Prepare 1 kg of deionized water, weigh 350 g of unmodified ordinary silica sol and add it to the deionized water. Stir for 30 min, then add 5 g of sodium vanadate and stir for 10 min. Add 1.5 g of sodium polyacrylate and continue stirring for 60 min to obtain the catalyst slurry. Take a glass fiber mat of appropriate size, immerse it in the above slurry, and after it is fully soaked, remove the glass fiber mat, drain off the excess slurry, and dry it in an 80℃ oven to obtain the catalyst glass fiber mat for comparison.
[0026] Catalyst glass fiber mats with the same area of 5*5 cm from Application Examples 1-3 were selected as Sample 1, Sample 2, and Sample 3, respectively. After weighing and recording the weight, they were fixed in a shaker. The shaker frequency was adjusted to 200 Hz to simulate the actual usage environment of the catalyst glass fiber mat. After a period of time, the fiber mat was removed and weighed, and the material dust loss rate was calculated (material dust loss rate = 1 - sample weight after test / initial sample weight before test). The dust loss rates of catalyst glass fiber mats prepared with different silica sols are shown in Table 1. Table 1 Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.
Claims
1. A method for preparing modified silica sol, characterized in that, include: S1, mix silica sol and ionic liquid at a mass ratio of 1:0.001-0.02, and stir at 200-600 rpm for 30-90 min at a temperature of 30-60℃ to obtain a preliminary mixture; S2, add a predetermined amount of silane coupling agent to the silica sol in the initial mixture, wherein the silane coupling agent and the silica sol in the initial mixture are mixed at a mass ratio of 1:0.01-0.1, and stirred at a temperature of 30-60℃ and a speed of 200-400rpm for 60-120min to obtain the intermediate mixture; S3. Add a pH adjuster to the intermediate mixture to adjust the pH value of the solution to 7-9, and then obtain the modified silica sol.
2. The method for preparing modified silica sol according to claim 1, characterized in that, In step S1, the solid content of the silica sol is 20%-50%.
3. The method for preparing modified silica sol according to claim 1, characterized in that, In step S1, the ionic liquid is a quaternary ammonium ionic liquid or an imidazole ionic liquid.
4. The method for preparing the modified silica sol according to claim 3, characterized in that, In step S1, the ionic liquid is one of 1-butyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium tetrafluoroborate, 2-hydroxyethyltrimethylammonium acetate, and tetrabutylammonium carboxylate.
5. The method for preparing modified silica sol according to claim 1, characterized in that, In step S2, the silane coupling agent is any one of γ-aminopropyltriethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, and vinyltrimethoxysilane.
6. The method for preparing the modified silica sol according to claim 1, characterized in that, In step S3, the pH adjustment reagent is hydrochloric acid or ammonia.
7. A modified silica sol, obtained by the preparation method according to any one of claims 1-6.
8. A catalyst slurry, characterized in that, By weight percentage, it includes the following components: Modified silica sol 10-40% 30-50% deionized water catalyst 1-10% Dispersant 0.1-1%.
9. The catalyst slurry according to claim 8, characterized in that, The catalyst is one of sodium vanadate, ammonium molybdate, and cobalt molybdate.
10. The catalyst slurry according to claim 8, characterized in that, The dispersant is one of sodium polyacrylate, hexadecyltrimethylammonium bromide, and alkylphenol polyoxyethylene ether.