Antibacterial Biophenol-based Nanofibrous Membranes For Protective Mask

The explosive growth and high-frequency flow of the population lead to the proliferation of various respiratory infectious diseases;meanwhile,the disease’s incidence and mortality increase year by year.To ensure the public’s health and society’s stabilization,it is urgent to do an excellent job protecting respiratory infectious diseases.Cutting off the transmission of respiratory infections by wearing a high-performance mask is the most effective means.However,the current fiber filter materials for protective masks,such as traditional textile fiber filter material,ordinary non-woven fiber filter material,molten-jet electret fiber filter material,and other protective functions,are not comprehensive.The fiber diameter and pore diameter of traditional textile fiber filter and typical non-woven fiber filter are large,which makes it challenging to filter germs and other particles efficiently,the charge of melt-blown non-woven fiber filter material dissipate as well,and the physical interception efficiency of the material is very low after the charge dissipation.Besides,the filter materials do not have bactericidal properties above all,and there is a risk of cross-infection and secondary infection.Electrospinning technology can prepare fiber filter materials with nanoscale diameter,ensuring the efficient filtration of particles.In addition,the electrospinning fiber filter material can be modified to make the material have a bactericidal property and enhance the protection ability of the material against respiratory tract infection.The current research results show that the electrospinning fiber filter material has the disadvantages of insufficient environmental protection raw materials,slow sterilization,and low efficiency,limiting the application of the material in protective masks.Therefore,the development of electrospinning fiber filter material with high filtration efficiency,low resistance pressure-drop,and strong sterilization performance is urgent.The electrospinning nanofibrous membranes to prepare protective masks is designed to the conditions of satisfaction:(1)The preparation of the fibrous membranes is based on the Green Principle to ensure that the preparation process and raw materials are environmentally harmless,and the preparation results are harmless to human body;(2)The fiber membrane has high filtration efficiency,low resistance pressure drop and long protective aging,which can effectively protect against aerosol of bacteria;(3)Fibrous membranes has the bactericidal function and can kill bacteria in aerosol quickly and efficiently.To realize the conditions,we mainly carried out research in the following four aspects and achieved certain results::(1)Polyvinyl butyral(PVB)with good spinning ability and non-toxic was selected as the polymer matrix of nanofibers;Eco-friendly biological phenolic antibacterial agents,salicylic acid,and its derivatives were selected as antibacterial additives;Choose green and safe ethanol as the single-solvent.The types and concentration of antibacterial agents were preliminarily screened by antibacterial experiments,the selected antibacterial agent type was determined to be 5-bromosalicylic acid(BSA)antibacterial agent,and the added concentration was 1wt%.(2)The preparation of BSA/PVB nanofibrous membranes with high filtration performance was realized by adjusting the experimental parameters.By adjusting polymer concentration,fiber base weight,and spinning humidity,different fibrous membranes were prepared.Moreover,the relationship between fiber structure and membrane filtration performance was analyzed by scanning electron microscope,aperture analyzer,and other characterization methods to realize the optimization of membrane filtration performance.The results showed that the fiber membrane prepared with a polymer concentration of 8wt%,fiber substrate weight of 2.5g m-2,and spinning humidity ≤35% had the best performance.The filtration efficiency of the fiber membrane was99.11%,the resistance pressure drop was 175 Pa,and the filtration efficiency was still more than 95%after using for more than 8 hours.(3)The fast and efficient bactericidal performance of the BSA/PVB nanofiber membrane was verified by controlling the contact time.The fiber membrane prepared with the best experimental parameters was taken as the experimental sample,Gram-positive bacteria and Gram-negative bacteria were used as test bacteria,the antibacterial properties of the fiber membrane were measured by controlling the contact time between the sample and the liquid in the antibacterial process.The results showed that BSA/PVB antibacterial nanofiber film had a broad-spectrum bactericidal effect,and when the contact time exceeded 10 minutes,the fiber film could kill 99.999% of bacteria.(4)The actual performance of the fiber membrane was verified by preparing a three-layer protective mask.The BSA/PVB nanofiber membrane is used as the core functional layer of the mask,and a homemade three-layer protective mask was prepared by selecting non-woven fabrics for masks sold in the market.The protective mechanism of the mask was analyzed,and the actual performance of the mask was verified by the bacterial filter according to the national standard.The results showed that the bacterial filtration efficiency of the composite mask was >99.9%,exceeding the highest standard.The preparation of BSA/PVB nanofibrous membranes provide a practical basis for the development of masks with durable and efficient filtration performance,rapid and efficient sterilization function,fill the vacancy of the filter material of the electrospinning antibacterial mask.