6 key parameters of calcium carbonate in plastic filling-3
Effect of particle size distribution on the quality of calcium carbonate
The particle size distribution of calcium carbonate is an important quality control indicator for modified masterbatch, and its detection methods mainly include screening method and particle size measurement method. The screening method uses "mesh number" to represent the particle size, which is a traditional and simple analysis method. The number of mesh holes per inch of the sieve is the mesh number. For example, a 500-mesh sieve corresponds to 25μm, while a finer electrodeposition sieve can be screened to 5μm (2500 mesh). However, the screening method is difficult to apply to ultrafine powders (less than 10μm) because the screening time is long and it is easy to clog.
In contrast, it is more scientific and accurate to use the actual particle size (micrometer μm) for particle size distribution analysis. The size of the particle size distribution range directly affects the processing performance of calcium carbonate and the quality of the final product. The narrower the particle size distribution, the more stable the material performance; the wider the particle size distribution, the greater the performance fluctuation. For example, the target particle size of 1250 mesh calcium carbonate is about 10μm, but if the particle size distribution range is 5-38μm, the following problems may occur:
1. Too small particle size: the specific surface area increases, it is easy to agglomerate, affecting the dispersion.
2. Too large particle size: the surface of the product is rough, affecting the appearance and performance.
Therefore, in practical applications, it is very important to control the particle size distribution range of calcium carbonate to ensure that its processing performance and mechanical properties meet the requirements of modified masterbatch and plastic products.
