Fluorine-free strongly dipolar polymers exhibit tunable ferroelectricity
- Jiahao Huang
- Guanchun Rui
- Yueming Yan
- Elshad Allahyarov
- Man-Hin Kwok
- Wenyi Zhu
- Li Li
- Shixian Zhang
- Zhiliang Pan
- Deyu Li
- Honghu Zhang
- Richard R. Mu
- Bin Zhao
- Qing Wang
- Philip L. Taylor
- Richard F. Haglund
- Q. M. Zhang
- Lei Zhu
2025-07-03
Current research on ferroelectric polymers centers predominantly on poly(vinylidene fluoride) (PVDF)–based fluoropolymers because of their superior performance. However, they are considered “forever chemicals” with environmental concerns. We describe a family of rationally designed fluorine-free ferroelectric polymers, featuring a polyoxypropylene main chain and disulfonyl alkyl side chains with a C3 spacer: −SO 2 CH 2 CHRCH 2 SO 2 − (R = −H or −CH 3 ). Both experimental and simulation results demonstrate that strong dipole-dipole interactions between neighboring disulfonyl groups induce ferroelectric ordering in the condensed state, which can be tailored by changing the R group: ferroelectric for R = −H or relaxor ferroelectric for R = −CH 3 . At low electric fields, the relaxor polymer exhibits electroactuation and electrocaloric performance comparable with those of state-of-the-art PVDF-based tetrapolymers.