High-dielectric-constant ceramic-powder polymer composites

A ceramic-powder polymer composite, making use of a relaxor ferroelectric polymer that has a high room-temperature dielectric constant as the matrix, is developed. The experimental data show that the dielectric constant of the composites with Pb(Mg1/3Nb2/3)O-3-PbTiO3 powders can reach more than 250 with weak temperature dependence. In addition, the composites under a proper preparation procedure exhibit a high breakdown field strength (> 120 MV/m), leading to a maximum energy storage density of more than 15 J/cm(3). Experimental results also indicate that the high electron irradiation does not have much effect on the dielectric behavior of Pb(Mg1/3Nb2/3)O-3-PbTiO3 powders, possibly due to the relaxor nature of the ceramic. (C) 2000 American Institute of Physics. [S0003-6951(00)04925-1].