Abstract：Calcium carbonate (CaCO₃) was successfully coated by SiO₂, then pol yaniline (PANI) was in situ polymerized to form a novel CaCO₃-SiO₂-PANI conductivity composite powders. The samples were characterized by the means of SEM, XRD, TG and resistivity meter, the effects of mass ratio m (CaCO₃-SiO₂) : m (An) on the morphology, structure and conductivity of CaCO₃-SiO₂-PANI powders were studied. The results shows that conductivity of CaCO₃-SiO₂/PANI powders decrease from 5.6 ×10^-2 to 5.7 ×10^-3 S·cm^-1with increasing mass ratio m (CaCO₃-SiO₂) : m (An) from 1:1 to 3:1. The morphology of CaCO₃-SiO₂-PANI changes obviously when mass ratio was 3:1 and CaSO₄ formed, coating with PANI did not change the structure of CaCO₃. The conductivity composite powders show good heat resistance and excellent conductivity when the temperature below 200 ℃.

Keywords: conductivity composite powders; calcium carbonate; morphology; structure; conductivity