Strategies to Improve the Water Resistance of Nanofibers Obtained by Suspension Electrospinning

ABSTRACT Suspension Electrospinning involves electrospinning a latex (an aqueous dispersion of polymer particles) with the help of a water‐soluble template polymer. This method is promising as it enables the spinning of hydrophobic polymers using water as an electrospinning medium, thereby eliminating the need for toxic organic solvents. However, Suspension Electrospinning presents some challenges, as the use of a template polymer is necessary to form continuous fibers, but increasing its amount reduces the fibers´ water resistance. This work focuses on producing water‐resistant nanofibers by optimizing template concentration and exploring new strategies. The minimum template concentration needed to produce uniform, water‐resistant nanofibers from a monomodal acrylic latex is identified. Additionally, a high solids content bimodal acrylic latex is spun for the first time, enhancing process productivity and allowing a 50% reduction in the template polymer compared to the monomodal system. Two additional novel strategies are employed to increase the water resistance of the nanofibers: thermal cross‐linking of a carboxylic acid functionalized latex with polyvinyl alcohol (PVA) and spinning a high glass transition temperature latex followed by its coalescence before the template removal. Finally, the effectiveness of PVA and polyethylene oxide (PEO) as template polymers is compared.