Electrospinning Composite Nanofibers. Conductive materials are used as collectors in the fabrication of nanofibers by electrospinning. Most non-conductive surfaces can be covered with aluminum foil. A stable potential difference is provided through the use of conductive materials. Fiber production is increased by using a conductive collector.
Due to the rapid accumulation of charge in non-conductive collectors, fewer fibers are collected and there is less coverage compared to conductive materials. The use of a porous collector also affects the properties of the fiber. Rotating rolls can be used to produce oriented fibers, giving the solvent more time to evaporate.
preparation of core-sheath composite nanofibers by emulsion electrospinning
It has been shown that the distance between the manifold and the tip of the syringe needle can also affect fiber diameter and fiber structure. If the distance between the needle and the collector is too small, the fiber will not have time to cure before reaching the collector. If the distance is too long, a vortex fiber structure may be obtained. Therefore, determining the optimum spacing is an important point in fiber manufacture.
Other factors affecting the diameter and morphology of electrospun nanofibers are environmental parameters. These are parameters such as humidity, pressure and temperature in the environment where the beam is located.
electrospinning nanofibers composites
High ambient humidity is an important parameter for fibers produced by electrospinning from solutions made with volatile solvents. Since the solvent evaporates quickly in a low-humidity environment, the solution always appears at the tip of the needle, causing the needle tip to clog.
As the ambient pressure decreases, the desire for the solution to flow into the syringe increases. This will start an unstable jet. Under low atmospheric pressure, the polymer solution tends to flow more. This causes an unstable jet to form. At higher pressure drops, the polymer jet creates bubbles. When the pressure is reduced to a certain level, electrospinning cannot take place as the charge sinks to the surface of the collector.