Research On The Preparation And Application Of Polyphenylene Sulfide-based Microporous Membrane

Membrane science and technology,which developed in recent years,has been widely applied in many fields.With the rapid development of membrane science and technology,the multifunctional and high-performance membranes are highly desired.Poly?phenylene sulfide??PPS?is a kind of high-performance thermoplastic polymer which possesses an excellent thermal property and good chemical and solvent resistance.On one hand,it can expand the application range of the membrane technology,such as the applications in acid,alkali and high-temperature environments.On the other hand,it can be used as a matrix for preparing functionalized membranes via harsh reactions.In this study,the performances of PPS microporous membrane were improved,and the functionalization and application of the PPS based membrane were explored.Filtration membranes have been successfully employed to treat water/oil emulsions.However,poor chemical and solvent resistance of general polymeric membranes limits the membranes for application in some harsh conditions.In this study,a porous PPS membrane with a rough concave topographic feature was fabricated,which exhibited excellent superoleophilicity and under-oil superhydrophobicity.The membrane was capable of separating both surfactant-free and surfactant-stabilized emulsions with a high flux.All of the water contents of the filtrates were below 300 ppm.The water droplets on the PPS membrane are in a stable Cassie state,which makes the membrane possesses excellent water resistance and superior reusability.The successful application of the thermally induced phase separation?TIPS?method may provide a new approach to fabricate the PPS membrane and improve its structure and properties.The coupling of membrane technology and the catalytic process is an important research direction for applications of membranes.In this study,nanosized titanium dioxide?TiO₂?with high crystallinity was synthesized on the surface of the PPS microporous membrane by the in-situ hydrothermal method.The conjugate structure was created on the membrane surface via a pretreatment.It is helpful to improve the drawbacks of TiO₂,including the wide band gap,the high electron/hole recombination rate,the low chemisorption to organic pollutants,and the agglomeration.There was a strong interaction between TiO₂ and the membrane matrix,leading to the effective migration and separation of electron-hole pairs.The band gap and electron/hole recombination rate were sharply decreased.Additionally,the chemisorption of the composite photocatalytic membrane was?3 times compared with the powdery TiO₂.The TiO₂@PPS membrane exhibited high photocatalytic activity and efficiency.Rhodamine?RhB?,methyl orange?MO?,and methylene blue?MB?can be degraded almost completely after being irradiated for 90 min under visible light.Furthermore,the water contact angle of the TiO₂@PPS membrane was 0°,and the membrane displayed superior anti-fouling and self-cleaning performances.