Preparation and dielectric properties of nano BaTiO₃-SiC_w/poly(vinylidene fluoride) ternary composite films

With poly(vinylidene fluoride) (PVDF) as matrix, 15wt% of CTAB modified silicon carbide nanowhisker (SiC_w) and nano BaTiO₃ (BT) particles modified by KH550 as fillers, the BT-SiC_w/PVDF ternary composite film was prepared. The composition and the micro-morphology of the samples were investigated by FTIR, XRD and SEM, respectively. It was illustrated that modified BT could be well dispersed in PVDF matrix by SEM analysis. The results show that KH550 particles can be successfully modified BT and BT does not change the crystal structure, SiC_w and BT can be well dispersed in the PVDF matrix. The dielectric constant of the BT-SiC_w/PVDF composite film is as high as 33 while the dielectric loss is only 0.154 correspondingly at the frequency of 500 Hz with loading of 10wt% BT at room temperature and reach optimal. The dielectric constant and dielectric loss of the composite film increase with increasing the temperature and reach the maximum value (freqyency f=500 Hz, dielectric constant ε_rmax=110, dielectric loss tanδ_max=1.3) at 120℃, which provide a strategy to find application in the buried capacitor that the results for research ternary ceramic material having a high dielectric constant dielectric material.