All-Organic Polymer Dielectrics Containing Sulfonyl Dipolar Groups and π–π Stacking Interaction in Side-Chain Architectures
Haoran Xu, Guanghu He, Sheng Chen, Sheng Chen, Shaonan Chen, Shaonan Chen, Rui Qiao, Hang Luo, Dou Zhang
Abstract
Although polymer dielectrics show wide application prospects in electronic and electrical fields, a low relative dielectric constant and a low energy density restrict their rapid developments. To overcome these shortcomings, a strategy is proposed to facilitate orientational polarization through the incorporation of the π–π stacked biphenyl side groups in dipolar polymers. In this study, sulfonyl-containing poly(norbornene)s with and without biphenyl groups were synthesized by ring-opening metathesis polymerization, denoted as PBTMD-SO2 and PTMD-SO2, respectively. Their dielectric behaviors and energy-storage properties were investigated. The dielectric constant of PBTMD-SO2 with the biphenyl side groups was as high as 11.1 at 25 °C and 1 kHz, which was nearly 35% higher than that of PTMD-SO2 due to the stronger orientational polarization. In addition, the dielectric loss in the range of 1 kHz to 1 MHz increased from 0.061 to 0.172 for PTMD-SO2 and from 0.075 to 0.110 for PBTMD-SO2. Electric displacement–electric field loops studies indicated that the discharge energy density of PBTMD-SO2 reached 1.69 J/cm3 at 180 MV/m with a high efficiency of 87.1%, which exceeded the discharge energy density of 1.29 J/cm3 for PTMD-SO2 at 200 MV/m. This work offers a new idea for the design of high-performance dielectric polymers.