Preparation of electrospun PVA@Ls@BAC@PDMS composite nanofibrous air filtration membrane with high efficiency removal for PM2.5 and excellent heat resistance

Development of water-soluble polymer air filtration materials attracts considerable attentions due to their environmentally friendly performance and high efficiency, but the balance of mechanical strength, efficiency and pressure drop still is a severe challenge. Focusing on this issue, polyvinyl alcohol (PVA), bamboo activated carbon (BAC) and sodium lignosulfonate (Ls) were combined to construct an electrospinning system with two filtration functions. In the PVA@Ls@BAC system, the 3D network constructed by the electrospun PVA based nanofibrous could effectively intercept PM2.5, and the introduced Ls enhanced the mechanical strength of PVA nanofibrous due to its good rigidity. In addition, the added negatively charged BAC facilitated the electrostatic adsorption of PM2.5 while also improved the heat resistance of the system. Moreover, polydimethylsiloxane (PDMS) was introduced to enhance the water resistance of the system. The resulting electrospun PVA@Ls@BAC@PDMS composite nanofibrous air filtration membrane exhibited excellent air filtration performance (98.67%), water repellency (123.7° of WCA), and reusable performance, as well as having good mechanical property and the tensile fracture strain reaching 112%. Because of its good performance and simple preparation process, the electrospun PVA@Ls@BAC@PDMS composite nanofibrous air filtration membrane has great application space.