Experimental And Simulation Study On Melt Electrospun Process And Fiber Performance

Electrospinning is a method of fabricating superfine fibers included solution electrospinning and melt electrospinning. Solvent-free and product of high purity make melt electrospinning become an important part of electrospinning. And it has gained wide attention among scientists. However, the complication of melt electrospinning setup and the relative thick fiber severely prevent the industrialization process of this method. In order to solve those problems, this study focuses on the experimental and simulation research of melt electrospun process and fiber performance to provide a way for melt electrospinning industrialization. The main contents are as follows:(1) With the self-made melt electrospinning setup, the effects of uniformity of the distribution of electric field on the instability appearing in the process of melt electrospinning were studied. By installing a circular plate paralleled with the collective plate on the spinneret the parallel electric field was formed. The influences of the size and location of the two plates on the instability of jets were studied by experiments and simulations. The outcomes show that the more uniform of the distribution of electric field is, the less the instability is.(2) With the self-made melt electrospinning setup assisting with hot airflow, the effects of hot airflow on the crystallization of electrospun fibers were studied. And the effects of annealing on the crystallization of electrospun fibers were explored. The important part of this setup is a heat gun. By changing the strength and temperature of the heat gun, the influences of different strength and temperature of hot airflow on the crystallization of electrospun fibers were studied. The results show that the strong strength and high temperature of hot airflow can improve the crystallization of electrospun fibers. By changing the time and temperature of annealing, it finds that the long time and high temperature can enhance the crystallization of electrospun fibers. However when the time and temperature reach a point, the crystallization of the electrospun fibers does not change any more.(3) With the self-made two centrifugal melt electrospinning setups, the differences between them were compared, the effects of centrifugal electrospinning on the fibers were studied. Using the first type of setup the effects of centrifugal electrospinning on the crystallization of fibers were studied. The experimental results demonstrate that this method can increase the crystallization of fibers. Using the second type of setup the effects of centrifugal electrospinning on the diameter of fibers were studied. The experiments show that this means can obtain superfine fibers in yield.