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Pulsed-UV light in the continuous flow of a photo-crosslinkable liquid can result in gelation and is a useful method to produce soft microfibers with uniform sizes. With modeling and experiments, we characterize some aspects of this fiber fabrication process. We model the spatial concentration profiles of radical species and molecular oxygen in the flow direction during light exposure, and predict the critical conditions for the onset of fiber formation and compare these predictions with experimental observations. We also characterize the different regimes of microfiber production (no polymerization, non-uniform fibers, and uniform microfibers), qualitatively characterize the rigidity of the fibers, and demonstrate that we can predictably control the length of the produced microfibers for a range of process parameters.
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This content will become publicly available on September 1, 2026
Magnetic torque-based method for quantifying the flexural rigidity of microfibers
Probing the flexural rigidity of micropillars and microfibers is challenging as they are short and difficult to handle. We developed a magnetic torque methodology where a coil-generated uniform magnetic field acts on a magnetic microrod attached to the fiber end, forcing it to turn. It is shown that magnetic torque bends microfibers in a circular arc, whose radius depends on the flexural rigidity. Magnetic microrods were fabricated by electroplating nickel on tungsten microwires. The methodology was validated with synthetic microfibers. Available magnetic stages for optical microscopes offering uniform magnetic fields within a millimeter-wide spot can be implemented to study a variety of beam-like microstructures.
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- Award ID(s):
- 2422802
- PAR ID:
- 10637673
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of Science: Advanced Materials and Devices
- Volume:
- 10
- Issue:
- 3
- ISSN:
- 2468-2179
- Page Range / eLocation ID:
- 100942
- Subject(s) / Keyword(s):
- Magnetic torque, Flexural rigidity, Microfibers, Electrochemical polishing, Electroplating, Magnetic probe, Biofibers
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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