Changing the dielectric properties of BaTiO3 filled poly(phenylene oxide) composites by control of their structure

The dielectric properties of BaTiO3 (BT) filled poly(phenylene oxide) (PPO) composites are investigated according to their structure, which is modified by filling the matrix with PPO-encapsulated BT particles and forming the semi-interpenetrating polymer network with triallyl isocyanurate (TAIC). Polymer encapsulation is most effective in lowering the permittivity and tan δ of the composite by suppressing the interface polarization. The copolymerization effect of TAIC is ignorable for a low dielectric matrix such as PPO. However, the dielectric values of the composites with low molecular weight-sized PPO, as the matrix, are decreased significantly by TAIC due to the constrained orientation polarization of the matrix.