Electrospinning (ES) is a process for fabricating polymer fibers that have diameters that range from tens of nanons to hundreds of microns, which has been studied for over 100 years. These fibers have been studied in applications such as: the enhancement of mechanical properties including increased sensor sensitivity and increased tensile strength, filtration enhancement, drug delivery systems, and as a lithography masking material.
In order to increase the effectiveness of ES, a real time feedback control mechanism to measure fiber diameters is needed. Currently only post-process methods of measuring fiber morphology, such as scanning electron microscopy or transmission electron microscopy, are used to measure ES fibers. Many parameters including: separation distance, applied voltage, polymer viscosity, polymer molecular weight, and flow rates are used to control fiber morphology.
Using these parameters in combination with a feedback control mechanism, a multiple-input multiple-output control mechanism could be developed. By using laser extinction tomography, a device was built to measure fiber diameters during deposition. The laser diagnostic device (LaD) has been able to measure the laser extinction while scanning through fiber depositions with limited repeatability.
Source: Montana Tech
Authors: Joshua Beisel