Hetero-functionalization of polyitaconates for developing improved polymer dielectrics: Merging sulfones with bulky/rigid cycles

Abstract

This work addresses the preparation of new polymer dielectrics working under the dipolar glass polymer (DGP) concept. Herein, we report the synthesis and characterization of four hetero-functionalized polyitaconates bearing sulfones as high dipole moment entities and norbornane or adamantane structures responsible for increasing the glass transition temperature (Tg) and thus the range of temperatures where they can work without degrading or showing high energy dissipation. As a result, all obtained polymers exhibited dielectric constants (εr’) between 5.1 and 6.2 while presenting low loss factors (Tan(δ) < 0.01), reaching the status of high-dielectric polymers with a low dissipative behavior. In addition, it was demonstrated that including bulky structures into their polymer backbone allows for an increase of up to 80 °C in their working temperature ranges, expanding the temperature range where they behave as DGPs in an outstanding manner. A complete structural, thermal and dielectric characterization was carried out in terms of infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), thermogravimetry (TGA), differential scanning calorimetry (DSC) and broad dielectric spectroscopy (BDS). Overall, these materials seem to fulfill the basic requirements to be considered good candidates for dielectric applications such as energy storage, confirming the versatility of polyitaconate-based materials.