Resumen de Aportacions al procés d'electrospinning per a la fabricació de nanofibres ordenades
Research in nanotechnology has recently undergone a significant interest. Nowadays it is possible to obtain nanofibers although most of parameters of the different processes to produce them remain still unknown. If fibers could be collected individually and somehow aligned, by reducing the diameter, the ratio of surface area versus fiber fineness would proportionally be increased together with the material resistance. That will spread the future applications of nanofibers to a very large range of possibilities. Electrospinning is a technique that can be used to produce nanofibers under the influence of an electrostatic field. Despite having proved that almost all polymers, either solution or melt, are able to be used in the electrospinning process, only a few of them have been tested, resulting always in a radomly oriented and nonwoven mat of fibers. The statistical tool for the design of experiments has been used first of all to check in situ which are the factors in the electrospinning process that most significantly affect the morphology of the obtained nanofibers, and secondly to be able to study quickly and easily the effect of these factors on the morphology of the resulting nanofibers, as well as the one with their interactions. The main conclusion directly drawn from the effects quantification and analysis is that the average diameter of fibers decreases with the increasing of the applied potential difference and that the diameter dispersion is smaller for both a larger concentration of the polymer solvent and a higher applied voltage. Later, a detailed study of electric field, both field lines and potential distribution, has been made by finite element simulation, obtaining the best results regarding the deposition of fibers somehow aligned when either some changes in both the electrical potential distribution and field lines refered to the elementary electrospinning assembly and/or the motion of electrical charges on the surface of the collector due to the movemnt applied to this were involved in the process.
