Dye, fluorophores and pigment coloration of nanofibers produced by electrospinning

Polymeric nanofibers produced by the electrospinning technique are widely used in industrial scale production. Nanofibers chiefly find applications in filtration media and active-barrier surfaces for medical, biological, and military applications. In such applications, the quantity and the uniformity of the nanofibers distribution play a leading role in the product characteristics. For this reason, there is considerable interest regarding the nanofibers recovering quantification and simplification of the qualitative analysis. With the aim to improve and simplify the nanofibers relevability, a coloration approach for nanofibers has been designed and tested. The coloration has been carried out by organic dyes, pigments, and organic fluorophores and the consequent nanofibers' color has been analyzed by optical analysis, colorimetry, and spectroscopy. The coloration obtained by different dyes has been compared and their effect on the nanofibers relevability has been investigated. Moreover, the leading role of the light scattering phenomenon on the nanofiber coloration efficacy has been investigated by comparing the coloration response of nanofibers and film samples on equal terms of dye content. The study has been carried out using polyamide-6 (PA6) as the testing polymer but the recovering quantification, the coloration approach, and the interaction between light and nanofibers can be extended to all the electrospinnable polymers. Copyright (C) 2008 John Wiley & Sons, Ltd.