Dielectric analysis of poly(methyl methacrylate) zinc(II) mono-pinacolborane diphenylporphyrin composites

Poly(methyl methacrylate) (PMMA) composites were made from a polar metalloporphyrin 5-(4′,4′,5′,5′-tetramethyl1′,3′,2′]dioxaborolan-2′-yl)-10,20-diphenylporphyrinato]zinc(II) (Zn(II)Bpin-DPP) in select weight % (wt%). Differential Scanning Calorimetry (DSC) showed that porphyrin acted as an antiplasticizer raising the glass transition (Tg) from 105 °C to 123 °C. Dielectric Analysis (DEA) was performed in the frequency range of 0.3 Hz to 100 kHz between −150 and 270 °C. Permittivity (?′), loss factor (?″) and dielectric response of beta (β), alpha beta (αβ), and conductivity relaxations were studied. Previous DEA data was limited to 190 °C. This study brings analysis to 270 °C which is start point for the first part of PMMA degradation. Thus forwarding DEA can be used to evaluate PMMA degradation. The electric modulus formalism is used to reveal the β and conductivity relaxations. The apparent activation energies (E_a) for the molecular relaxations are presented. AC (σ_AC) and DC (σ_DC) conductivity are also evaluated.