The study of electrospun nanofibers and the application of electrospinning in engineering education
Abstract
During electrospinning, a polymer solution becomes an electrically driven jet as it travels to a grounded plate. While the behavior of pressure-driven liquid jets has been extensively studied in fluid mechanics, none of the characteristics of fluid jet break up have been applied to electrospinning. Calculating Weber number can describe what type of breakup occurs as the polymer jet travels to the plate, which could also predict the surface morphology of electrospun fibers. Polyethylene oxide (PEO) solution was electrospun at different voltages to test whether the morphology of the electrospun fibers can be predicted through calculating Weber number. While the continuing research of electrospinning is important, the subject of electrospinning can be used as a course to teach students engineering principals over a semester. Due to the vast interdisciplinary subjects associated with electrospinning, teaching the subject as a course will give students an understanding of critical thinking skills as well as first hand accounts of research. Four weight percent PEO solution was electrospun at a range of testing parameters until the desired results were achieved, beaded or non-beaded fibers. The Weber numbers were calculated and compared to the electrospun material created. Analyzing the surface morphology revealed a beaded to non-beaded trend in nanofibers corresponding to high-to-low Weber numbers. The same trend continued for higher weight percents of PEO solutions electrospun. The course will have many learning objectives the instructor is expected to have the students achieve, building the objectives to help the students become better researchers and to learn the material. Splitting the course into three five week sections will help students understand each component of the electrospinning process, as well as fundamental engineering equations and theories. The students at the end of the semester should be able to recreate the electrospinning process on their own and create nanofibers of varying sizes. The course should also excite students about pursuing more advanced degrees in scientific fields.