In this study, the key factors for controlling the average fiber diameter and diameter distribution of fibers made via simultaneous centrifugal spinning and UV initiated polymerization are elucidated. Through systematic investigation, it was found that the average fiber diameter has a strong dependence on monomer delivery rate through the orifice, which can be intuitively linked to both the orifice diameter and monomer mixture viscosity. On the other hand, the breadth of the fiber diameter distribution can be controlled by the spin speed of the rotating spinneret. Carefully tuning these process parameters allows near independent control of average fiber diameter and its distribution, which could provide access to a widely tailorable range of fibers appropriate for different applications. Finally, under optimized process conditions, crosslinked fibers with average diameters of approximately 1.5 μm can be produced, which are one to two orders of magnitude smaller than photocured fibers fabricated in previous reports and comparable with the smallest melt blown nonwoven fibers produced commercially. Coupled with the advantages of cross-linked fibers made by in-situ photopolymerization, the capability to produce small fibers with tailored diameter distributions by centrifugal spinning could further establish this technology as a competitive alternative to existing approaches.
Bibliographical noteFunding Information:
We gratefully acknowledge partial financial support from the Welch Foundation (grant #F-1709 ) and the National Science Foundation through the CLiPs NSF-STC , DMR-0423914 . CJE gratefully acknowledges partial financial support from the DuPont Young Professor Award and 3M Non-Tenured Faculty Award. We also gratefully acknowledge help from Andrew Worthen and Prof. Keith Johnston for their help in taking surface tension measurements.
- Centrifugal spinning
- Reactive processing