Morphological and permeable properties of antibacterial double-layered composite nonwovens consisting of microfibers and nanofibers

Melt-blown nonwovens consisting of only micron-sized fibers were not sufficient to completely prevent bacterial invasion using a structure property of filter media composed of micro pore size alone. To improve the percent filtration efficiency (E) and antibacterial activity of nonwovens, a novel type of polyurethane (PU) composite nonwovens composed of double layers was fabricated using a combination of melt-blowing and electrospinning. In this study, melt-blown thermoplastic polyurethane (TPU) nonwovens were used to support the mechanical property to act as a substrate layer. In addition, the electrospun PU nanofibrous layer containing the AgCl nanoparticles (NPs) as an antibacterial agent provided antibacterial activity and filtration efficiency. Double-layered composite nonwovens were characterized in terms of pore structure and antibacterial activity. The filtration efficiency of PU composite nonwovens containing an AgCl NPs was improved in comparison with PU composite nonwovens, and their antibacterial activity against three micro-organisms was 99.9%.