Research On Janus PTPS And PSA/PAN@SiO₂ Nanofiber Membranes In The Fields Of Air Filtration And Oil-water Separatio

With the development of economy and society,the mass discharge of industrial waste gas and oily wastewater seriously endangers the ecological environment and human health.In recent years,membrane filtration technology with high efficiency,low cost and low pollution has been widely concerned.The nanofiber membrane prepared by electrospinning technology has high specific surface area,high porosity and flexible surface structure,and has high application value in water treatment and air filtration.However,the structural stability,the complexity of the preparation process and the recyclability of the fiber membrane materials must be considered.Therefore,in the face of the actual harsh environment,how to develop powerful filters to control air pollution and purify oily wastewater is still a huge challenge for researchers.Based on the above problems,the research content of this paper is as follows:（1）The polyacrylonitrile@TiO₂/polyvinylidene fluoride-hexafluoropropylene@SiO₂（PTPS）nanofiber membranes were prepared by sequential electrospinning technology.Due to its unique double-layer structure and the synergistic effect of multiple components,the composite filter can overcome the tradeoff effect between high filtration efficiency and low air resistance,achieving a filtration efficiency of99.7%(removal of PM_0.3)at a pressure drop of 27 Pa.The combination of the hygroscopic PAN@Ti O₂ layer and the self-cleaning PVDF-HFP@SiO₂ layer gives Janus filters a distinct advantage in the field of personal protection.In addition,due to its asymmetric wettability,the Janus membrane has a switchable oil-water separation capability and can efficiently separate different oil-water mixtures and emulsions with high throughput and separation efficiency.This powerful Janus nanofiber filter has broad application prospects in air filtration and oil-water separation.（2）We successfully developed a polysulfonamide/polyacrylonitrile@silica（PSA/PAN@SiO₂）nanofibrous membrane,which was used for air filtration in the actual complex environment.In the process of air purification,the synergistic action of multiple components can effectively overcome the conflict between the removal efficiency of pollution particles and the high resistance.At the low pressure of 30±2 Pa,the air purification efficiency(PM_0.3)of PSA/PAN@SiO₂ composite membrane can reach 99.05±0.13%.Due to the excellent stability of PSA and SiO₂,the composite membrane still has stable air filtration performance in complex environments（strong acid,strong alkali and high temperature）.In addition,PSA/PAN@SiO₂ composite membrane can effectively filtration the smoke produced by cigarettes for a long time,which has practical application value.