Flexible composites with a high electrical permittivity are pursued in materials research, due to their potential applications in electrical devices. We synthesized such ceramic-polymer composites from BaTiO3 and epoxidized natural rubber. The influence of BaTiO3 concentration on cure characteristics, mechanical (static dynamic), dielectric, and morphological properties of the composites was investigated. The tensile strength and elongation at break decreased with BaTiO3 loading, while the storage modulus and permittivity of composites increased. As for dynamic electrical properties, the dielectric loss factor and tan delta of the composites showed a maximum peak within the frequency range extending up to 10(5) Hz, reflecting the relaxation process of the polymer matrix. All of the composites showed two peaks in the frequency dependence of electric modulus, due to conductivity and molecular relaxation. Scanning electron microscopy micrographs confirmed the 0-3 structure of composites, with isolated BaTiO3 particles.
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