Greatly enhanced permittivity in BaTiO_(3)-epoxy dielectric composites with improved connectivity of ceramic phase

BaTiO_(3)-epoxy dielectric composites were prepared by curing the liquid epoxy monomer that infiltrated into the partially-sintered BaTiO_(3)porous ceramics.The BaTiO_(3)volume fraction of the composites maintained around 58.6%with increasing the sintering temperature from 600℃to 1000°C,while the significant microstructure evolution,improved connectivity of BaTiO_(3)phase and dramatical increase in permittivity from 102 to 697 were observed.The permittivity and BaTiO_(3)volume fraction further increased to 2328 and 83.5%for the sintering temperature of 1250℃.The present composites had the permittivity 102 orders of magnitude higher than the 0-3 type ones,and the extraordinary results were mainly attributed to the improved connectivity of BaTiO_(3)phase that benefited from partial sintering.The connectivity also had a significant effect on the temperature dependence of permittivity,and good combination of temperature-stable high permittivity,low dielectric loss and relatively low ceramic fraction could be obtained by regulating the connectivity of BaTiO_(3)ceramic phase.