Nanofibrous mats were obtained from electrospinning Nylon-6 solutions with concentrations of 30 and 35 wt% and were tested for filtration of polystyrene particles in suspension. Some experimental results were compared with the simulated ones. In the simulation, the two-dimensional structures were constructed by randomly depositing a nanofiber, which was assumed as an ellipse with an aspect ratio of 100, one by one. The nanofiber size is assumed to be polydisperse. The results showed that simulated configurations resembled real nanofibers with polydisperse diameters. Fibers from higher solution concentration were larger, resulting in larger pore size, which was confirmed with simulations. Varying the size distribution around the same average value did not make any difference to the surface coverage but it affected 2D pore areas for the systems at low fiber density. In addition, the probability for a particle to pass through the porous structure was less when the fiber density was higher and the particle diameter was larger, which was consistent with the filtration test. Lastly, water flux measurement could yield the void volume fraction as well as the volume-averaged pore diameter, which was found to be greater than the averaged 2D pore diameter from SEM micrographs by the quantity related to the fiber size. 1. Introduction Electrospinning technique is an easy method to produce nanofibers with size in submicron or nanometer range, by applying the electrical force generated by the electric field between the end of the metal needle and the ground collector. The liquid source for spinning fibers may be a polymer melt or a polymer solution. A polymer melt or a polymer solution is placed in a syringe. Once the applied electrical force is greater than the surface tension of the hanging hemisphere drop at the end of the syringe needle, the liquid is pulled out of the needle and swirled onto the collector surface. Continuous fibers are produced in this manner. While the solvent evaporates, the final nonwoven nanofibrous structure is solidified. A large number of papers discussing the production of nanofibers from various polymer systems and their applications have been published [1–5]. The research on nanofibers is still receiving more and more attention. Indeed, the benefit of large surface area to volume ratio of nanofibrous structures improves their performance in many aspects including higher mechanical strength, an increase in surface activity, and an increase in adsorption capacity. Therefore, nanofibers were widely studied for use as sensors [1],
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