The biophysical properties of films prepared from polymethyl methacrylate (PMMA) blended with maleated castor oil (COMA) with composition 70/30 wt% filled with different concentrations of calcium carbonate (CaCO₃) in the micro and nano scales have been studied. The incorporation of the filler in the polymeric matrix exhibits remarkable improvement in its properties. The prepared films were characterized through different techniques such as, thermo gravimetric analysis TGA, scanning electron microscope SEM, differential scanning calorimetry DSC, in addition to dielectric properties which were carried out at range of frequency from 0.1 Hz to 5 MHz and temperature range from 30 to 90 ^oC. The data obtained for the two investigated systems indicate that the dielectric permittivity ε' and dielectric loss ε" increased by increasing either the concentration of the filler or the temperature. The analysis of the imaginary part of the electric modulus M" which was carried out using Havriliak-Negami function revealed three relaxation times characterizing the conductivity relaxation, segmental molecular motion and the local motion of the side groups attached to the main polymer chain. The slight decrease in such relaxations noticed above 60^oC (Tg) could be attributed to the cooperative reorientation motion of the polymeric segments, while that happened at concentration above 30 wt % from the micro and above 10 wt % from the nano filler could be attributed to the retardation of the dipole matrix which become weak.This result is supported by the calculations of the activation energies carried out using Arrhenius equation.The electrical conductivity σ were studied over frequency range (0.1Hz to 5 MHz) indicated that COMA is recommended to be used for electrostatic dissipation applications. Moreover the enzymatic degradation was carried out by immersing the prepared films in phosphate buffer solution. The weight remaining was found to decrease with the increase in either the time of immersing or the concentration of the filler added.