Light-assisted electrospinning monitoring for soft polymeric nanofibers

Abstract

A real-time tool to monitor the electrospinning process is fundamental to improve the reproducibility and quality of the resulting nanofibers. Hereby, a novel optical system integrated through coaxial needle is proposed as monitoring tool for electrospinning process. An optical fiber (OF) is inserted in the inner needle, while the external needle is used to feed the polymeric solution (PEO/water) drawn by the process. The light exiting the OF passes through the solution drop at the needle tip and gets coupled to the electrospun fiber (EF) while travelling towards the nanofibers collector. Numerical and analytical models were developed to assess the feasibility and robustness of the light coupling. Experimental tests demonstrated the influence of the process parameters on the EF waveguide properties, in terms of waveguide length (L), and on the nanofibers diameter distribution, in terms of mean $$\widehat{D}$$ D ^ and normalized standard deviation $$\chi$$ χ . Data analysis reveals good correlation between L and $$\widehat{D}, \chi$$ D ^ , χ (respectively maximum correlation coefficients of $${\rho }_{L,\widehat{D}}$$ ρ L , D ^ = 0.88 and $${\rho }_{L,\chi }$$ ρ L , χ = 0.84), demonstrating the potential for effectively using the proposed light-assisted technology as real-time visual feedback on the process. The developed system can provide an interesting option for monitoring industrial electrospinning systems using multi- or moving needles with impact in the scaling-up of innovative nanofibers for soft systems.

Comparison of the mechanical characteristics of produced nanofibers by electrospinning process based on different collectors

“…Electrospinning is fast developing from a single-fluid process [ 6 , 7 ] to coaxial [ 8 ], tri-axial [ 9 ], side-by-side [ 10 ], and other complicated processes [ 11 ]. Correspondingly, uniaxial [ 12 ], core-shell [ 13 ], Janus [ 14 ], tri-layer core-shell nanostructures [ 15 ] have been reported for a wide variety of functional applications. However, one of the most important properties of mechanical performance is often ignored in literature, which is vital for functional applications regardless of the complexity [ 16 ].…”