Star product! As a commonly used filler, what are the characteristics of calcium carbonate?
Calcium carbonate: a multifunctional star filler in the plastics industry
Calcium carbonate (CaCO₃), as an indispensable filler in the plastics industry, has become a key component in plastic products with its excellent performance and economy. It not only improves the performance of plastics, but also effectively reduces production costs, so it plays a vital role in the field of plastic processing.
Types and characteristics of calcium carbonate
Calcium carbonate is mainly divided into light calcium carbonate (PCC) and heavy calcium carbonate (GCC). Heavy calcium carbonate comes from natural minerals such as calcite, marble, and limestone. It is processed by mechanical grinding and has a large bulk density, generally 0.8 to 1.3 grams per cubic centimeter, and a low oil absorption value, usually 40 to 60. Light calcium carbonate is prepared by chemical methods. The raw material is limestone. It is obtained through calcination, digestion, carbonization and other processes. The bulk density is relatively low, generally 0.5 to 0.7 grams per cubic centimeter. In terms of cost, GCC has a large price difference due to different particle sizes and origins, while PCC has a low cost due to its simple production process and wide sources.
Effect of particle size and distribution on plastic performance
The particle size and distribution of calcium carbonate have a significant effect on plastic performance. Generally speaking, the finer the particle size of GCC, the better the performance of the filled plastic. PCC has excellent filling performance due to its small particle size. In terms of processing performance, GCC has good fluidity and is suitable for plastic products that require high fluidity; PCC may require more sophisticated temperature control and longer plasticizing time. PCC-filled plastic products have good surface gloss and are suitable for products with high appearance requirements. Although GCC can also improve surface quality after treatment, PCC usually performs better.
Application of calcium carbonate in the field of plastics
The application range of calcium carbonate is very wide, and its role in plastic products cannot be underestimated. For example, in soft polyvinyl chloride (PVC), the addition of calcium carbonate can not only increase the hardness of the plastic, but also enhance the dimensional stability. As the amount of calcium carbonate added increases, the hardness increases and the elongation decreases.
PVC profiles and pipes: The use of calcium carbonate can significantly improve the dimensional stability and hardness of the product.
Wire and cable sheath: In the production of wire and cable sheath, calcium carbonate improves the processing performance and physical properties of the material, meeting the needs for good processing adaptability and suitable physical properties.
PVC calendering film: The use of calcium carbonate improves the gloss of the product, improves the surface quality, and effectively reduces the specific gravity, making the product lighter.
PVC soles and decorative patches: The addition of calcium carbonate effectively improves the hardness and wear resistance of these parts, enhances the durability of the soles and patches, and meets the needs of shoe use.
