A facile method to modify polypropylene membrane by polydopamine coating via inkjet printing technique for superior performance

Membrane surface functionalization based on mussel-inspired polydopamine (PDA) deposition for enhancing antifouling ability has attracted considerable attention. However, high cost of dopamine (DA) and long-time of reaction during self-polymerization of DA in aqueous solution remain the major problems impeding its practical application. This study provided a first report on a low-cost and facile membrane modification approach based on inkjet printing of DA and sodium periodate (SP) to rapidly deposit PDA on polypropylene (PP) membrane. Compared with the pristine PP membrane and DA printed PP membrane, the PDA-SP coated PP membrane demonstrated superior hydrophilicity (67.2°), high pure water permeability (2156.8 L·m^-2·h^-1) and antifouling property, due to the improved oxidation degree of PDA. Moreover, the modified membrane possesses good chemical stability in aqueous solution over the wide range of pH 2-9. The inkjet printing integrated oxidant-induced mussel-inspired modification proposed in this study is substrate-independent, and can be applied to various geometries and materials, showing broad application prospects in membrane fabrication.