  Poly(Methyl Methacrylate) (PMMA) and CaCu3Ti4O12 (CCTO) composites were
fabricated via melt mixing followed by hot pressing technique. These were
characterized using X-ray diffraction (XRD), thermo gravimetric (TGA), Thermo
Mechanical (TMA), Differential scanning calorimetry (DSC), Fourier transform
infrared (FTIR), and Impedance analyser for their structural, thermal and
dielectric properties. Composites were found to have better thermal stability
than that of pure PMMA. However, there was no significant difference in the
glass transition (Tg) temperature between the polymer and the composite. The
appearance of additional vibrational frequencies in the range 400-600 cm-1 in
FTIR spectra indicated a possible interaction between PMMA and CCTO. The
composite, with 38 Vol % of CCTO (in PMMA), exhibited remarkably low dielectric
loss at high frequencies and the low frequency relaxation is attributed to the
space charge polarization/MWS effect. The origin of AC conductivity
particularly in the high frequency region was attributed to the electronic
polarization.
