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Co dispersant of fumed silica

In a powder system, when dry (low moisture content), particles are less than 75 μ m. The forces between the particles cause the powder to generally bond and agglomerate (especially 25 μ Particles with a size below m), which is challenging for fluidization. At this point, vapor phase silica can be added to solve this problem. The small particle size and high surface energy of fumed silica enable it to adsorb on the surface of the coating powder and form a surface layer on the powder's surface, improving the powder's dispersion. To enhance the adhesion of the dispersant aids to the powder particles, it is best to use hydrophobic white carbon black, as they can maximize the adsorption force of the powder particles within the small micron size range. At the same time, due to their hydrophobic nature, covering the powder particles can reduce water adsorption, preventing agglomeration during flow. Adding fumed silica in the same coating system can significantly shorten the dispersion time and improve production efficiency. However, it is worth noting that it is better to disperse white carbon black completely. The additional amount of white carbon black as a dispersant aid should not be too large, generally not exceeding 1%, because excessive addition will cause the thixotropic property of the system to be too strong, resulting in insufficient edge shear force during dispersion and a frozen shape, affecting dispersion efficiency. In exceptional cases, such as zinc-rich paint requiring the addition of 2%, it can be used with other rheological additives, and alcohol solvents can be used to adjust the rheological properties of fumed silica. The refractive index of the matting agent-raged silica is 1.46, which is close to the refractive index of the film-forming resin and has no effect on the color of the paint film. Migration to the surface of the paint film during film formation can produce expected roughness on the surface of the paint film, significantly reducing its surface gloss, and is an excellent matting agent. The extinction effect mainly depends on three properties of the product: pore volume ratio, particle size, and surface treatment. When using fumed silica, attention should be paid to matching the thickness of the paint film. Using fumed silica with beautiful particles in thick film paint is a delicate surface that cannot produce appropriate roughness. Conversely, if using granulated fumed silica in thin film paint, although its matting effect is perfect, the roughness of the paint film surface will not be acceptable to most users. If you are looking for high quality, high purity and cost-effective fumed silica, or if you require the latest price of fumed silica, please feel free to email contact mis-asia.

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