Synthesis and Mechanism of Electronic Calcium Carbonate

With the breakthrough of electronic information industry, new requirements were proposed for the development of electronic information materials. As one of the raw materials of electronic components, calcium carbonate (CaCO₃) has the characteristics of reducing the dependence of the dielectric constant on the temperature, changing the Curie temperature, improving the resistance to voltage and ferroelectric properties. CaCO₃ with high purity, small particle size, uniform particle size distribution and calcite crystal type present excellent characteristics, and its preparation technology has attracted much attention. In this paper, electronic CaCO₃ was prepared by decomposition reaction. The morphology and structure of CaCO₃ were analyzed by scanning electron microscope, X-ray diffraction etc. Moreover, the effects of the key parameters, such as temperature and additive amount on the morphology of CaCO₃, were discussed. The results showed that the nearly spherical CaCO₃ with a particle size of 2.5 μm, uniform distribution particle size and purity of 99.86% was obtained when the decomposition reaction temperature was 30 ℃, the addition mass fraction of tartaric acid was 1.0% and the mole ratio of refined calcium chloride, ammonium bicarbonate and ammonia water was 1∶1∶1. The aim of addition of tartaric acid is to form calcium tartrate with calcium ion. The complexation and spatial structure of calcium tartrate promote the nucleation of calcium carbonate and inhibit its growth.