电纺丝方法是一种成本低廉，装置简单，适用材料广泛的微纳米纤维制备方法，也是目前唯一能够大量连续制造微纳米纤维的方法，具有良好的工业应用潜力。传统的电纺丝方法得到的纤维为随机排列的无纺布形态，纤维排列的无序性大大限制了其在某些领域的应用，所以，研究获得有序排列的电纺丝纤维的方法具有十分重要的意义。本文主要研究射流受力的改变对约束电纺丝射流弯曲运动的影响，致力于实现电纺丝纤维的可控沉积和单方向有序排列。本文在传统电纺丝装置中添加上平板和带电压偏置的聚焦圆环以构建收敛的外电场分布，从而获得收敛的外电场力以约束射流的扩散运动，实现电纺丝纤维的可控沉积。实验证明得到的电场分布有利于减小纤维的沉积范围。当喷射装置与收集板相对移动时，微观呈螺旋结构的纤维就可以在有限的扩散宽度内定向沉积；收集速度的变化只改变纤维的形态，并不影响纤维的沉积落点和扩散宽度。通过对获得的纤维形貌和纤维直径的分析可以推断：同时引入上平板和聚焦圆环的装置可以完全抑制射流的弯曲甩动，使之沿着中心轴运动。为了长时间的获得有序排列的连续电纺丝纤维，本文采用双喷丝头对喷方法来进行纤维的单方向有序排列。使用分别接正、负电压的相对放置的两个喷丝头喷出的射流在空中吸引、碰撞，形成整体呈电中性的纤维束，然后卷绕至高速旋转的收集圆筒上就可以实现纤维的有序排列。实验证明对喷电纺丝方法可以获得良好的单方向排列的微纳米纤维。增加收集速度可以提高纤维排列的有序度，而增加溶液浓度可以提高纤维所能承受的拉伸速度；此外，喷丝头间距和装置电场分布也会对排列效果产生影响。另外，通过提高聚合物溶液的浓度，可以在合适的速度下完全抑制射流的弯曲甩动。通过无弯曲甩动的对喷电纺丝方法可以制备排列有序度十分理想的纤维，而且收集过程变得十分稳定。本文利用对喷电纺丝方法分别制备了包裹纳米颗粒的复合纤维，珠-丝状结构的复合纤维以及双组份的复合纤维，这些不同结构的纤维均可以得到比较好的有序排列效果。

The electrospinning technique is a low-cost, simple and flexible method to manufacture mico- and nanofibers from various polymer materials. It is also considered as the only method which is applicable for the mass production of continuous nanofibers and accomplished for potential industrial applications. However, the nanofibers generated from the conventional electrospinning setups are randomly aligned in form of nonwovens. The inability of fiber alignment limits the applications of electrospun fibers and mats, so it is of significance to control the orientation of fibers. In this study, the ways of assisted electric field focusing and opposite jetting are respectively developed to control the electrospinning jet trajectory and achieve the fixed and uniaxial alignment of electrospun fibers.In this study, an upper metal plate and a series of bias focusing rings are introduced to the conventional electrospinning setup to form convergent electric field distribution, which can promote the restraint of electrospun jet trajectory and the achievement of controllable deposition of electrospun fibers. It is demonstrated that the modified electric field distribution is benefit to the reduction of the diffusion area of fibers in experiments. The fibers with helical structures are deposited along the same direction by varying the relative position of spinneret and collecting plate. The variety of collecting velocity only affects the structures of helical fibers and has little influence on the depositing position and diffusion range. Through the analysis of morphologies and diameters of fibers, it is concluded that the modified electric field distribution may completely restrict the bending instability of jet and make the fibers move along a straight line.The opposite jetting method is also presented to produce continuous and uniaxially aligned electrospun fibers for a long time. Two stainless steel spinnerets are assembled in opposite directions and respectively connected to the opposite electrical potentials provided by high voltage power supplies. Jets are ejected from the two spinnerets and collide at the middle of the setup because of the attraction of opposite charges. So an electrically neutral yarn consisted of multi fibers is formed and aligned by the stretching of rotating cylinder. The experimental results reveal that well alignment of fibers is achieved by the opposite jetting method. The increase of collecting velocity is helpful for the ordered alignment and the increase of solution concentration improves the ultimate collecting velocity. The influence of interval of spinnerets and electric field distribution on the fiber alignment is also studied. Besides, the bending instability of jet can be totally restricted at a proper collecting velocity when the solution concentration is increased to a critical value. When the bending instability is suppressed, fibers with almost perfect alignment can be generated by the opposite jetting method and the collecting process is very steady.The opposite jetting method is also used to fabricate composite fibers encapsulating nanoparticles, beaded fibers and side-by side bicomponent fibers. Well alignment of composite fibers is also achieved in all these manufacturing processes.