Investigation of Dielectric Constant and Electrical Conductivity of Poly(MA-co-MMA)/Ce(NO3)3 Composites by Response Surface Methodology for Advanced Dielectric Applications

In this study, poly(maleic anhydride-co-methyl methacrylate) [poly(MA-co-MMA)] copolymer and their Ce(NO3)3-filled composites were synthesized and systematically investigated. The copolymer was prepared via free radical polymerization using azobisisobutyronitrile (AIBN) as the initiator in 1,4-dioxane medium. Poly(MA-co-MMA)/Ce(NO3)3 composites were fabricated through a solution mixing technique in accordance with the response surface methodology (RSM) design. Fourier transform infrared spectroscopy (FTIR) results indicated that no significant chemical interaction occurred between the polymer molecule and Ce(NO3)3 particles. Scanning electron microscopy (SEM) images revealed a relatively uniform dispersion of Ce(NO3)3 particles within the polymer, resulting in a rougher surface with increasing filler content and that aggregation occurs at 20 wt%. The presence of Ce(NO3)3 particles in the polymer was confirmed by x-ray diffraction (XRD) analysis. The effects of frequency, applied voltage, and Ce(NO3)3 content on dielectric constant (epsilon) and electrical conductivity (sigma) were optimized using RSM, and the significance of these parameters was evaluated by analysis of variance (ANOVA). An increase in Ce(NO3)3 content significantly enhanced the electrical conductivity, while the applied voltage exhibited no statistically significant effect on dielectric properties. ANOVA results identified Ce(NO3)3 content as the most influential parameter in the developed model.