# Extension rate of the straight jet in electrospinning of poly(N-isopropyl acrylamide) solutions in dimethylformamide: Influences of flow rate and applied voltage

Yu Wang, Takeji Hashimoto, Chang Chou Li, Yang Cheng Li, Chi Wang

11 引文 斯高帕斯（Scopus）

## 摘要

In the electrospinning process, the measurement of extension rate of the straight jet is not an easy task. In this study, the diameter profile of the tapering straight jet is determined with a laser light-scattering technique. Afterwards, the jet extension rate ɛ is derived and used to compare with the solution-intrinsic rates, for example, the terminal relaxation rate and the Rouse relaxation rate. The extension rate of the straight jet depends on position: it is highest near the cone apex (region I) and decays to a constant value in the major jet (region II) until approaching the jet end (region III), at which the extension rate abruptly drops to nearly zero, that is, ɛI > ɛII ≫ ɛIII ∼ 0. The jet diameter in region III is independent of solution concentration and applied voltage, but is scaled to the flow rate with an exponent of ∼0.37. The derived exponent is consistent with a simple prediction based on the counterbalance between the stretching electric force and the compressive force induced by the air drag force. Provided that air friction becomes overwhelming at the straight jet end, the long electrified jet is likely to buckle, thereby triggering the instability of jet whipping.

原文 English 319-329 11 Journal of Polymer Science, Part B: Polymer Physics 56 4 https://doi.org/10.1002/polb.24544 Published - 2018 二月 15

• 凝聚態物理學
• 物理與理論化學
• 聚合物和塑料
• 材料化學