Study of ac conductivity and Dielectric Properties of PMMA with Fe_2O_3+ Al_2O_3 Composite films

摘要

The PMMA with Fe_2O_3+ Al_2O_3 films at different weight percent have been used for measurement of dielectric properties such as dielectric constant, dielectric loss and ac conductivity as a function of frequency over the range 50 Hz - 5 MHz at room temperature. The dielectric constant and the dielectric loss (tan 8) of the polymer composite films decreases exponentially at lower frequencies over the range 100 Hz-1 KHz, where as above 1 KHz the values of dielectric constant remains same. But, it has been observed that the value of dielectric constant of PMMA composite films with Fe_2O_3+ Al_2O_3 increases as weight percent of Fe_2O_3+ Al_2O_3 increases. The ac conductivity of the polymer composite films remains constant over the frequency range 50 Hz to 300 KHz and afterwards it increases exponentially. Further, PMMA with Fe_2O_3+ Al_2O_3 have been characterized using X-Ray diffractometer for the crystallinity. The morphological studies have been made using the FESEM.