Fabrication and formation mechanism of closed-loop fibers by electrospinning with a tip collector
Yan Xu1, †, 
, Yu Miao1, †, , Han Wen-Peng1, You Ming-Hao1, Zhang Jun-Cheng1, Dong Rui-Hua1, Zhang Hong-Di1, Long Yun-Ze1, 3, ‡,
, Yu Miao1, †, , Han Wen-Peng1, You Ming-Hao1, Zhang Jun-Cheng1, Dong Rui-Hua1, Zhang Hong-Di1, Long Yun-Ze1, 3, ‡, Schematic illustration of electrospinning segment with closed-loop fiber and the model for formation of closed-loop structure. During the bending flight, the jet (a) is charged in the intensive electric field and the mutual repulsion is involved (b), the increasing Coulomb repulsion splits the jet in the middle, and then a closed-loop is formed (c). The closed-loop fibers are obtained on the collector (d).
