Bhugra Vaibhav Singh, Maddah Mohsen, Williams Grant V, Plank Natalie, Nann Thomas
School of Chemical and Physical Sciences, Victoria University of Wellington Kelburn Parade Wellington 6012 New Zealand.
School of Mathematical and Physical Sciences, University of Newcastle University Drive, Callaghan NSW 2308 Australia
RSC Adv. 2019 Oct 2;9(54):31233-31240. doi: 10.1039/c9ra06470b. eCollection 2019 Oct 1.
Diisopropylammonium bromide (DIPAB) doped poly(vinylidene difluoride) (PVDF) nanofibers (5, 10 and 24 wt% DIPAB doping) with improved and tunable dielectric properties were synthesised electrospinning. DIPAB nanoparticles were grown during the nanofiber formation. X-Ray diffraction (XRD) patterns and Fourier transform infrared spectroscopy (FTIR) proved that electrospinning of DIPAB doped PVDF solutions led to the formation of a highly electro-active β-phase in the nanofibers. Electrospinning in the presence of DIPAB inside PVDF led to very well aligned nanofibers with preferred (001) orientation that further enhanced the effective dipole moments in the nanofiber structures. The dielectric properties of the composite nanofibers were significantly enhanced due to the improved orientation, ionic and interfacial polarisation upon the applied electrospinning process, ionic nature of DIPAB and the interface between the PVDF nanofibers and equally dispersed DIPAB nanoparticles inside them, respectively. The relative dielectric constant of the PVDF nanofibers was improved from 8.5 to 102.5 when nanofibers were doped with 5% of DIPAB. Incorporating DIPAB in PVDF nanofibers has been shown to be an effective way to improve the structural and dielectric properties of PVDF.
通过静电纺丝合成了掺杂二异丙基溴化铵（DIPAB）的聚偏氟乙烯（PVDF）纳米纤维（DIPAB掺杂量为5%、10%和24%（重量）），其介电性能得到改善且可调节。在纳米纤维形成过程中生长出了DIPAB纳米颗粒。X射线衍射（XRD）图谱和傅里叶变换红外光谱（FTIR）证明，对掺杂DIPAB的PVDF溶液进行静电纺丝会导致纳米纤维中形成高电活性的β相。在PVDF内部存在DIPAB的情况下进行静电纺丝，会得到排列非常整齐、具有择优（001）取向的纳米纤维，这进一步增强了纳米纤维结构中的有效偶极矩。复合纳米纤维的介电性能显著增强，这分别归因于在施加的静电纺丝过程中取向改善、离子和界面极化、DIPAB的离子性质以及PVDF纳米纤维与其中均匀分散的DIPAB纳米颗粒之间的界面。当纳米纤维掺杂5%的DIPAB时，PVDF纳米纤维的相对介电常数从8.5提高到了102.5。已证明在PVDF纳米纤维中掺入DIPAB是改善PVDF结构和介电性能的有效方法。
