Abstract

'This project ultimately targets the application of polymer nanofibers in new, cavity-free lasers. To this aim, it wants to tackle the still unsolved problems of the process of electrospinning in terms of product control by the parameters affecting the dynamics of electrified jets. The electrospinning is based on the uniaxial elongation of polymeric jets with sufficient molecular entanglements, in presence of an intense electric field. It is a unique approach to produce nanofibers with high throughput. However, the process is still largely suboptimal, the most of nanofiber production being still carried out on an empirical basis. Though operationally simple, electrospinning is indeed complex as the behavior of electrified jets depends on many experimental variables making fully predictive approaches still missing. This project aims to elucidating and engineering the still unclear working principles of electrospinning by solutions incorporating active materials, with a tight synergy among modeling, fast-imaging characterization of electrified jets, and process engineering. Once optimized, nanofibers will offer an effective, well-controllable and cheap material for building new, cavity-free random laser systems. These architectures will enable enhanced miniaturization and portability, and enormously reduced realization costs. Electrospun nanofibers will offer a unique combination of optical properties, tuneable topography and light scattering effectiveness, thus being an exceptional bench tool to realize such new low-cost lasers, which is the second project goal. The accomplishment of these ambitious but well-defined objectives will have a groundbreaking, interdisciplinary impact, from materials science to physics of fluid jets in strong elongational conditions, from process to device engineering. The project will set-up a new, internationally-leading laboratory on polymer processing, making a decisive contribution to the establishment of scientific independence.'