Dielectric Properties of PVDF/MgO Nanocomposites Thin Film with Various Annealing Temperatures

摘要

Poly(vinylideneflouride)/nano-magnesium oxide (PVDF/MgO) nanocomposites with MgO loading percentage of 7% were annealed with various annealing temperatures ranging from 70°C to 170°C. The PVDF/MgO(7%) thin films were fabricated using spin coating technique with MIM structure. The dielectric constant of PVDF/MgO(7%) was studied over a wide range of annealing temperatures with rapid removal from the oven once the annealing was utilized. The nanocomposites thin films annealed at temperature of 70°C (AN70) shows an improvement in the dielectric constant of 23 at 10~3 Hz compared to unannealed sample (UN), which was 21 at the same frequency. However, as the annealing temperatures were increased from 90°C (AN90) to 170°C(AN170), the dielectric constant of PVDF/MgO(7%) were found to decrease from 16 to 7 respectively, which were lower than the UN thin films. AN70 also produced low value of tangent loss at low frequency, (tan δ) indicating that, annealing at temperatures 70°C is favourable temperature used to improve the dielectric constant of PVDF/MgO(7%).