1.Select the appropriate dispersion equipment
In different viscosities and systems, it is necessary to select the appropriate dispersion equipment. In coating systems with lower viscosity, high-speed shear dispersers can be selected for the dispersion of fumed silica.
In silicone rubber with high viscosity, it is necessary to choose kneaders or open mills, etc. for the dispersion of powder. In powder systems, it is necessary to choose dispersion methods such as three-dimensional high-speed dispersion or grinding dispersion. In addition, the characteristics of the equipment also need to be considered, such as for the speed range, for power demand, for the type of stirring blades, for cooling or heating functions, etc. Youdaoplaceholder4 ensure that the equipment has the functions and performance to meet the requirements of the dispersion task.
2.Select an appropriate dispersion process
Different dispersion intensities, dispersion times, and the amount of dispersed materials all have a significant impact on the dispersion of powder. It is not the case that the longer the time or the greater the intensity, the more conducive it is to dispersion. Here, we need to take into account energy efficiency and whether there is an issue of over-dispersion. Over-dispersion can also cause particle re-agglomeration or structural damage, resulting in the performance of fumed silica not being well demonstrated. Therefore, choosing an appropriate dispersion process is of vital importance.
3.Select the appropriate dispersion aid
Dispersion AIDS are conducive to reducing the surface tension between fumed silica and the liquid interface, which is more beneficial for the wetting of fumed silica and the dissolution of agglomerated particles, thereby achieving the purpose of reducing viscosity. Meanwhile, the dispersing agent will form a double electric layer on the surface of the fumed silica particles. This double electric layer will generate electrostatic repulsion, making it difficult for the particles to aggregate and thus maintaining a dispersed state. The selection of appropriate additives is an extremely important factor in dispersion and is closely related to its storage performance.