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Title: A vertically translating collection system to facilitate roll-to-roll centrifugal spinning of highly aligned polyacrylonitrile nanofibers

Centrifugal spinning is a fiber spinning method capable of producing fibers in the nanoscale diameter range from a multitude of polymers, including polyacrylonitrile (PAN). With a traditional centrifugal spinner, fiber can be rapidly spun and collected on static collection posts. However, the use of posts inevitably forms a dense fiber “ring” that is incompatible with roll-to-roll manufacturing processes. In this work, factors that influence throughput and scalability of highly aligned centrifugally spun PAN fibers are explored. A custom centrifugal setup is used to vertically translate collected fibers during the spinning process to distribute them over a large surface area. In addition, factors that affect PAN fiber diameter during the spinning process are investigated, including spinneret to collector distance, rotational speed, and humidity. Resulting data demonstrates that these factors can be independently optimized to reliably produce quality PAN fiber in the nanoscale diameter range. Furthermore, the fiber mass collection rate can be increased without affecting sample quality when the vertical translation speed is increased. This work demonstrates the potential scalability of centrifugal spinning to quickly produce large amounts of highly aligned nanofiber in a cheap, efficient, and reliable manner, and also lends the ability to be collected in a roll-to-roll fashion.

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Author(s) / Creator(s):
Publisher / Repository:
Springer Science + Business Media
Date Published:
Journal Name:
Discover Materials
Medium: X
Sponsoring Org:
National Science Foundation
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