Tensile, dielectric, and thermal properties of epoxy composites filled with silica, mica, and calcium carbonate

• Published in: Journal of materials science. Materials in electronics 2014-05, Vol.25 (5), p.2111-2119
• Main Authors: Poh, C. L., Mariatti, M., Ahmad Fauzi, M. N., Ng, C. H., Chee, C. K., Chuah, T. P.
• Format: Article
• Language: English
• Subjects: Calcium carbonate; Characterization and Evaluation of Materials; Chemistry and Materials Science; Dielectric properties; Fillers; Materials Science; Mica; Minerals; Optical and Electronic Materials; Polymer matrix composites; Silicon dioxide; Thin films
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-014-1847-9

The minerals silica, mica, and calcium carbonate (CaCO 3 ) were used as fillers to produce epoxy thin film composites for capacitor application. The effects of filler loading and type on the morphology, tensile, dielectric, and thermal properties of the epoxy thin film composites were determined. Results showed that epoxy thin films with 20 vol% filler loading showed good dielectric properties, thermal conductivity, and thermal stability. However, the tensile properties of the thin films were reduced as the filler loading was increased due to brittleness. Dielectric constant and dielectric loss of epoxy/inorganic composite films generally increased with increasing mineral filler loading. Meanwhile, the presence of mineral filler improved the thermal stability of the thin film composites. The highest dielectric constant of 5.75 with 20 vol% filler loading at a frequency of 1 MHz was exhibited by the epoxy/CaCO 3 composite, followed by epoxy/mica and epoxy/silica. Therefore, the epoxy/CaCO 3 composite is the most potential candidate for capacitor application. Moreover, precipitated CaCO 3 provided better tensile properties and slightly improved the dielectric properties compared with mineral CaCO 3 .