CN-121991530-A - Modified calcium silicate, preparation method and application thereof, and paint

Abstract

The invention provides modified calcium silicate, a preparation method and application thereof, and a coating, and belongs to the technical field of coatings. The invention mixes Na 2 SiO 3 solution, ca (OH) 2 solution, modifier and water to carry out hydrothermal modification to obtain the modified calcium silicate. According to the invention, the modifying agent increases the lipophilicity and dispersibility of calcium silicate, improves the compatibility of the calcium silicate with the coating, and further optimizes the mechanical properties of the coating, so that the prepared coating has good adhesion and mechanical properties. The parameters of hydrothermal modification are further limited, the crystallization degree and deagglomeration of the modified calcium silicate are improved by increasing the temperature, the crystal growth can be optimized by prolonging the reaction time of the hydrothermal modification, but secondary agglomeration can be caused by overlong reaction time, the uniform mixing is ensured by rotating speed, and the composition of a product phase is influenced by the molar ratio of Ca/Si. The invention limits that Na 2 SiO 3 solution is obtained from high-silicon solid waste, and realizes the dual purposes of high-value utilization of the solid waste and reduction of the coating cost.

Inventors

• ZHANG YONGFENG
• LIU GANG
• WANG WEIJIANG
• MA HAOYUAN

Assignees

• 内蒙古工业大学

Dates

Publication Date

20260508

Application Date

20260227

Claims (8)

1. 1. The preparation method of the modified calcium silicate is characterized by comprising the following steps of: Mixing Na 2 SiO 3 solution, ca (OH) 2 solution, a modifier and water for hydrothermal modification to obtain modified calcium silicate, wherein the modifier comprises one or more of polyethylene glycol, stearic acid, sodium stearate, triethanolamine and liquid paraffin; The hydrothermal modification time is 35-70 min, and the temperature is 80-95 ℃; the mass of the modifier is 1-1.7wt% of Na 2 SiO 3 in the Na 2 SiO 3 solution.
2. 2. The method according to claim 1, wherein the molar ratio of Ca in the Ca (OH) 2 solution to Si in the Na 2 SiO 3 solution is 0.8-1.8:1.
3. 3. The preparation method according to claim 1, wherein the hydrothermal modification is performed under stirring, and the stirring speed is 500-800 r/min.
4. 4. The method of claim 1, wherein the Na 2 SiO 3 solution is obtained from high-silicon solid waste comprising one or more of microsilica, high-silicon coal ash, and gangue.
5. 5. The modified calcium silicate produced by the production method according to any one of claims 1 to 4.
6. 6. Use of the modified calcium silicate of claim 5 in the field of coatings.
7. 7. A coating is characterized by comprising the modified calcium silicate, titanium dioxide, heavy calcium, kaolin, styrene-acrylic emulsion, an auxiliary agent and water according to claim 5, wherein the auxiliary agent comprises a dispersing agent, a wetting agent, propylene glycol, a leveling agent, a film-forming auxiliary agent, an antifoaming agent, a preservative, a thickening agent and cellulose.
8. 8. The coating according to claim 7, wherein the modified calcium silicate in the coating is 11.3-30.1% by mass based on the wetting modified calcium silicate.

Description

Modified calcium silicate, preparation method and application thereof, and paint Technical Field The invention relates to the technical field of coatings, in particular to modified calcium silicate, a preparation method and application thereof, and a coating. Background The inorganic environment-friendly coating has become a research hot spot in the field of coating in recent years due to the characteristics of low VOC (volatile organic compound), non-toxicity, strong weather resistance and the like. The inorganic environment-friendly paint development technology system is mature gradually at present, and comprises an aqueous inorganic paint synthesized by silicate, silica sol, phosphate and other film forming substances, which is widely applied to the outer wall of a building, and an inorganic-organic hybrid system combining the durability of inorganic materials and the flexibility of organic materials (such as silicone-acrylate emulsion composite paint) by adding nano SiO 2、TiO2 and the like to improve the antibacterial property, self-cleaning and wear resistance of the paint, wherein the proportion of organic components is strictly controlled to keep the environment-friendly property. The inorganic coating does not need an organic solvent in terms of environmental protection performance, meets environmental protection standards, is resistant to high temperature, ultraviolet rays and acid and alkali, has a service life of 15-20 years (about 5-10 years of traditional emulsion paint), can be suitable for scenes such as tunnels and steel structures, can replace part of epoxy resin coating, and can be used for ships and bridges (such as water-based inorganic zinc-rich coating functional coating, radiation refrigeration coating and mildew-proof coating). Calcium silicate is an inorganic compound composed of calcium, silicon and oxygen, exists in a large amount in the natural world (such as minerals), and meanwhile, calcium silicate products with various performances are also prepared in the industry, so that the calcium silicate has been widely applied to industries of cement, paint, heat insulation materials and the like. The structural unit of the calcium silicate is a silicon oxygen tetrahedron and is in a chain structure, and a plurality of micropores are formed in the calcium silicate, so that the calcium silicate has a loose and porous structure and high specific surface area, and has good thermal stability and mechanical properties, and is widely focused at home and abroad. And the calcium silicate has excellent biocompatibility, chemical stability and mechanical property, and has wide application in the fields of building materials, biomedicine, environmental management and the like. However, the calcium silicate in the prior art has the problems of easy agglomeration and poor compatibility with an organic matrix, and limits the application of the calcium silicate. Disclosure of Invention In view of the above, the invention aims to provide modified calcium silicate, and a preparation method, application and paint thereof. The modified calcium silicate prepared by the invention has good dispersibility, good compatibility with an organic matrix, and good adhesion and mechanical properties of a coating formed by the prepared coating. In order to achieve the above object, the present invention provides the following technical solutions: The invention provides a preparation method of modified calcium silicate, which comprises the following steps: Mixing Na 2SiO3 solution, ca (OH) 2 solution, a modifier and water for hydrothermal modification to obtain the modified calcium silicate, wherein the modifier comprises one or more of polyethylene glycol (PEG), stearic acid, sodium stearate, triethanolamine and liquid paraffin. Preferably, the hydrothermal modification time is 35-70 min, and the temperature is 80-95 ℃. Preferably, the molar ratio of Ca in the Ca (OH) 2 solution to Si in the Na 2SiO3 solution (Ca/Si molar ratio) is 0.8-1.8:1. Preferably, the mass of the polyethylene glycol is 1-1.7wt% of Na 2SiO3 in the Na 2SiO3 solution. Preferably, the hydrothermal modification is performed under stirring, and the stirring speed is 500-800 r/min. Preferably, the Na 2SiO3 solution is obtained from high-silicon solid waste, and the high-silicon solid waste comprises one or more of silica fume, high-silicon coal ash and coal gangue. The invention also provides the modified calcium silicate prepared by the preparation method. The invention also provides application of the modified calcium silicate in the field of paint. The invention also provides a coating, which comprises the modified calcium silicate, titanium dioxide, heavy calcium, kaolin, styrene-acrylic emulsion, an auxiliary agent and water, wherein the auxiliary agent comprises a dispersing agent, a wetting agent, propylene glycol, a leveling agent, a film-forming auxiliary agent, a defoaming agent, a preservative, a thickening agent and cellulose. Preferably