The Effect of ZnO nanoparticles Filler on Complex Permittivity of ZnO-PCL Nanocomposite at Microwave Frequency

ZnO Nanoparticle was succesfully prepared by microwave irradiation method. The nano particles were then used as filler in the ZnO-PCL nanocomposites. The composites were prepared via the melt blend technique. The effect of the different percentages of the ZnO nanoparticles filler on the complex permittivity of the ZnO-PCL nanocomposite was investigated using themagnitudes of the reflection coefficient from the open ended coaxial sensors to determine complex permittivity of a sample under test.The different percentages used are 25%, 35%, 45%, 50% and 70% ZnO nano fillers. The result from the measurement showed that the nano filler significantly affected the value of the complex permittivity of the ZnO-PCL nanocomposites. Amongst other observations, its was found that the dielectric constant of the material under test (MUT) increases as the filler content increases. The result also showed that the dielectric constant at 8 GHz is higher than the dielectric constant at 12 GHz for all samples used. Measurement result showed that the 70% ZnO nano filler produced a mean complex permittivity of (Ɛr=4.07-j0.71).