Time and poling history dependent energy storage and discharge behaviors in poly(vinylidene fluoride-<Emphasis Type="Italic">co</Emphasis>-hexafluoropropylene) random copolymers |
| |
Authors: | Fang-xiao Guan Jing Wang Ji-lin Pan Qing Wang Lei Zhu |
| |
Institution: | (1) Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, Xi’an Jiaotong University, Xi’an, 710049, China |
| |
Abstract: | We studied cycle time (0.01–10 s with triangular input waves) and poling history (continuous versus fresh poling) dependent
electric energy storage and discharge behaviors in poly(vinylidene fluoride-co-hexafluoropropylene) P(VDF-HFP)] films using the electric displacement — the electric field (D–E) hysteresis loop measurements. Since the permanent dipoles in PVDF are orientational in nature, it is generally considered
that both charging and discharging processes should be time and poling history dependent. Intriguingly, our experimental results
showed that the charging process depended heavily on the cycle time and the prior poling history, and thus the D–E hysteresis loops had different shapes accordingly. However, the discharged energy density did not change no matter how the
D–E loop shape varied due to different measurements. This experimental result could be explained in terms of reversible and irreversible
polarizations. The reversible polarization could be charged and discharged fairly quickly (< 5 ms for each process), while
the irreversible polarization depended heavily on the poling time and the prior poling history. This study suggests that it
is only meaningful to compare the discharged energy density for PVDF and its copolymer films when different cycle times and
poling histories are used. |
| |
Keywords: | P(VDF-HFP) random copolymer Charging and discharging behaviors Time and poling history dependence Dipole switching Compensation polarization |
本文献已被 CNKI 万方数据 SpringerLink 等数据库收录! |
| 点击此处可从《高分子科学》浏览原始摘要信息 |
| 点击此处可从《高分子科学》下载免费的PDF全文 |