Hydrogen-Bond-Free Piperazine Polyamides with Ultralow Dielectric Loss

Polyamide, as a polar polymer, possesses a large intrinsic dipole moment and excellent mechanical properties, making it a highly promising dielectric material. Nevertheless, the dipoles in traditional polyamides are constrained by hydrogen bonding, resulting in a diminished capacity for dielectric polarization and significant dielectric losses. In this study, traditional diamine was replaced with piperazine to fabricate a hydrogen-bond-free polyamide by employing structural design, which alleviated the limitation of hydrogen bonding on dipole polarization and considerably reduced the dielectric loss of the polyamide. The results demonstrated that the piperazine-12 polyamide prepared with piperazine and adipic acid exhibited a low dielectric loss of 0.0027 at 103 Hz, a dielectric constant of 4.38 at 103 Hz, and a breakdown strength exceeding 149 MV/m. The approach outlined in this paper offers an effective method for designing and improving the dielectric performance of polyamides. This piperazine polyamide is expected to be an emerging organic dielectric material for applications in thin-film capacitor volumes.