Polysulfone Hybrid Ulyrafiltration Membrane Prepared With Cu₂O-g-?L-DOPA?-Ag/PSF And Its Antibacterial Properties

Polysulfone(PSF)is widely used for the preparation of ultrafiltration(UF)membranes due to its excellent chemical resistance,good mechanical properties and thermal stability.However,the hydrophobic nature of PSF often causes fouling of microorganism?cell secretions?protein and organic matters,leading to a reduction of separation performance?efficiency and operating life.Aiming at solving these problems,in this thesis,physical blending with Cu20-g-(L-DOPA)-Ag and Cu2O NWs was used to construct antibiofouling PSF UF membranes to improve the separation effect and antibacterial properties.The main contents are as follows:(1)The screw dislocation-driven Cu2O nano wires were synthesized in Fehling's solution by reducing Cu2+ to Cu+ in the role of glucose.L-Dopa was grafted on the Cu2O NWs by self-polymerization in aqueous solution.Cu2O NWs could fix Ag+ because of the adhesion layer of poly-L-Dopa;then,Ag+ was reduced to Ag0;finally,Cu2O-g-(L-DOPA)-Ag/PSF was prepared.(2)The hybrid polysulfone(PSF)membranes blending with different ratios of nanoparticles were prepared via phase inversion induced by immersion precipitation technique.The morphology and performance of the membranes were characterized by the tests of SEM?flux and metal ion leakage.Cu2O NWs and Cu2O-g-(L-DOPA)-Ag were uniformly dispersed in membrane;The highest pure water flux were 131.3 L m-2 h-1 and 178.0 L m-2 h-1,which were 225.0%and 266.3%higher than the PSF membrane;the mean pore size and porosity were 10.6 nm 81.0%and 28.5 nm?74.4%;lower ion leakage was existed in Cu2O NWs/PSF and Cu2O-g-(L-DOPA)-Ag/PSF,the leakage of Cu2+ and Ag+ after about 200 hours were 0.630%?0.423%and 1.533%?0.027%.The nanowires in the hybrid membranes had better stability.(3)The hybrid membranes showed antibacterial properties against Escherichia coli.The bacteriostatic circle diameters of Cu2O/PSF and Cu2O-g-(L-DOPA)-Ag/PSF against E.Coli were 12 mm and 28 mm.And the inhibitory rate of Cu2O-g-(L-DOPA)-Ag/PSF reached 100%.The experimental results showed that Cu2O-g-(L-DOPA)-Ag is a kind of successful fungicide.