Abstract:
As a type of polymeric membrane with excellent comprehensive performance, polyether sulfone (PES) membrane is widely applied in many fields, including blood purification and water treatment fields. However, there are still some drawbacks exist during the current application of PES membranes: the main disadvantage is related to its relatively hydrophobic character. Membrane fouling is directly related to the hydrophobicity, which is caused by adsorption of nonpolar solutes, hydrophobic particles or bacteria. Meanwhile, when contacting with blood, proteins will rapidly adsorb onto the surface of the PES membrane and the adsorbed protein layer may lead to further undesirable results, such as platelet adhesion, aggregation and coagulation. As the consequence, the antifouling property and blood compatibility of PES membranes need to be improved. In addition, PES membrane is stable in water. Being an inert membrane, PES membrane acts only as a barrier in the separation process. Thus, the performances of PES membrane would be weakened upon unavoidable membrane fouling, and they cannot be applied in cases where self-regulated permeability and selectivity are required. As a result, smart PES membrane which can self-regulate their permeability and selectivity via the flexible adjustment of pore sizes and surface properties also needs to be developed. With the aim of achieving these purposes, endowing the PES membranes with special functions by various modification methods has aroused more and more attention. In this review, the widely used modification methods for functionalized PES membranes were briefly introduced. Meanwhile, the recent studies of design and fabrication of PES membranes with various functions were summarized, including: (1) the anticoagulation, antifouling and antibacterial membranes for blood purification and biomedical engineering; (2) the stimuli-responsive membranes with switchable permeability and selectivity; (3) the modified membranes with improved adsorption performance for wastewater treatment. Finally, we give the future perspective of the research and development directions of the functionalized PES membranes.