High dielectric constant and low-loss, carbon black/CaCu3Ti4O12/epoxy composites for embedded capacitor applications

The growing demand for miniaturization and increased functionality of electronic devices has accelerated the research for materials with high dielectric constants, low dielectric losses, and good mechanical properties. In this study, a low-cost three-phase epoxy resin composite using calcium copper titanate (CCTO) and carbon black (CB) as fillers was developed, and its dielectric, mechanical, and dynamic mechanical properties were studied in detail. The composites were prepared using solution casting method and characterized by scanning electron microscopy and X-ray diffraction analysis. The dielectric properties of the composites were investigated over a frequency range of 100 Hz–1 MHz. At 60 wt% CCTO and 3 wt% CB loading, they exhibited a maximum dielectric constant of 60 and loss of 0.092. The optimized composites exhibited a tensile strength of 38 MPa and Young's modulus of 2.5 GPa. The dynamic mechanical analysis showed that the glass transition temperature improved in the composites.