Research On Preparation And Properties Of Polyether Sulfone Thermo-responsive Ultrafiltration Membrane

As a highly efficient means of separation, ultrafiltration membrane separation technology has been widely used, especially in the field of water treatment. However, with the development of science and technology, the existing ultrafiltration membrane materials can not meet the more complex environmental requirements. “Smart” membrane material with the characteristics of environmental stimuli response emerged. As the most common environmental factors, temperature can be artificially controlled and designed. Therefore, the preparation of thermo-responsive ultrafiltration membrane is becoming the focus of current research.In this paper, thermo-responsive ultrafiltration membrane was prepared by blending polyether sulfone(PES) and the graphene oxide grafted with poly N-isopropylacrylamide(GO-g-PNIPAAm). It can not only improve the hydrophilicity and anti-pollution ability of PES ultrafiltration membrane, but also give the membranes for the temperature-sensitive nature to achieve specific separation goals.Ultrafiltration Membranes was prepared by immersion precipitation phase inversion process, using N,N-dimethylacetamide(DMAc) as solvent, polyvinyl pyrrolidone(PVP) as an additive, and the coagulation bath is distilled water. Taking three levels of PES content, PVP content and coagulation bath temperature into account, the orthogonal experiment was designed to prepare a series of PES ultrafiltration membranes. The optimum preparation parameters were obtained by the characteristic study of ultrafiltration membrane, such as permeability, morphology, chemical stability and anti-pollution ability etc. The optimum condition to prepare ultrafiltration membranes are those, the content of PES is 14 wt%, PVP content is 8 wt%, and coagulation bath at a temperature of 30 oC.Thermo-responsive nano material(GO-g-PNIPAAm) was synthesized via atom transfer radical polymerization(ATRP). And it was characterized by FTIR, SEM, EDS methods. The results confirmed the expected nano material synthesis.Thermo-responsive ultrafiltration membranes were prepared by blending different content of GO-g-PNIPAAm with PES. Temperature sensitivity, porosity, hydrophilicity, mechanical strength, thermal stability and other properties of modified membrane were studied to obtain the optimum dosage. The modified membrane showed excellent performance when the addition amount of GO-g-PNIPAAm is 0.5 wt%, and it can be applied in separation process of different temperatures intelligently.