| 摘要 |
Microfiltration membranes achieve high retention of bacteria and viruses by pore-size exclusion by the diameters of the fibers in the scaffold layer. The membranes have a high permeation flux as compared with conventional commercial micro filtration membranes under the same applied pressure. Ultra-fine nanofibers (fiber diameters from 3 nanometers to 50 nanometers and lengths from about 100 nanometers to about 5000 nanometers) are infused into, or deposited onto the surface of fibrous filtration media. Negatively charged ultra-fine nanofibers can include polysaccharide nanofibers prepared by a 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)INaBrINaCIO oxidation system in aqueous solution. Ultra-fine polysaccharide nanofibers having a large number of carboxylate groups are produced. (0.7-1.0 mmol/g cellulose) The carboxylate groups are negatively charged, and can interact with positively charged polymers/molecules by forming a complex. Such ultra-fine polysaccharide nanofibers have positive charges, that are effective for the removal of bacteria and viruses through adsorption.
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