聚合物分子链取向度是决定纤维机械性质和物理性能的关键结构参数。然而，理解和大幅调控纤维大分子链取向仍面临巨大挑战。本文提出一种新型的静电纺丝方法，通过控制纺丝过程中的电场来有效调节分子链取向。与典型的静电纺丝相比，新型静电纺丝通过将电场施加在圆环上而非针头上来分离控制电场。得益于这一变化，实现了一种新的电场分布，从而产生非单调变化的牵伸作用力。结果表明，聚环氧乙烷（PEO）纳米纤维的大分子链取向得到显著改善，实现了超高红外二向色性比。与此同时，PEO射流细度可有效降低80%左右，纳米纤维直径从约298 nm降低至约114 nm。并且，与普通材料中高取向导致的高结晶度不同，该方法在提高纤维分子链取向度的同时使结晶度从74.9%显著降低至31.7%。这项工作为制备具有优化取向-结晶度特性的先进电纺纳米纤维提供了新的认识。

The degree of polymer chain orientation is a key structural parameter that determines the mechanical and physical properties of fibers. However, understanding and significantly tuning the orientation of fiber macromolecular chains remain elusive. Herein, we propose a novel electrospinning technique that can efficiently modulate molecular chain orientation by controlling the electric field. In contrast to the typical electrospinning method, this technique can piecewise control the electric field by applying high voltage to the metal ring instead of the needle. Benefiting from this change, a new electric field distribution can be realized, leading to a non-monotonic change in the drafting force. As a result, the macromolecular chain orientation of polyethylene oxide (PEO) nanofibers was significantly improved with a record-high infrared dichroic ratio. This was further confirmed by the sharp decrease in the PEO jet fineness of approximately 80% and the nanofiber diameter from 298 to 114 nm. Interestingly, the crystallinity can also be adjusted, with an obvious drop from 74.9% to 31.7%, which is different from the high crystallinity caused by oriented chains in common materials. This work guides a new perspective for the preparation of advanced electrospun nanofibers with optimal orientation-crystallinity properties, a merited feature for various applications.