Figure 4.

Coaxial electrospinning schematic diagram: Polymer solution 2 is passed through the inner capillary tube, while polymer solution 1 is passed through the outer capillary tube. The Taylor cone is formed where the inner solution (polymer solution 2) is surrounded by the outer solution. The jet erupts from the Taylor cone, and during that process, the polymer in the inner layer is coated with the polymer in the outer layer. The dried fiber with a core-shell design is then deposited on the collector.