Tunable pore size micro/submicron-sieve membranes by soft lithography

Membrane filtration is widely used for advanced water and wastewater treatments because of many favorable features it offers. Critical issues in membrane processes are membrane fouling as well as tortuous and broad size distribution of membrane pores. In this study, micro- and submicron-sieve membranes with uniform, non-tortuous pores were fabricated using a soft-lithographic technique. Due to the precisely controlled pore size, spatial distribution and non-tortuous quality, the membrane flux per surface porosity was shown to be greatly enhanced in comparison with conventional membranes with a tortuous pore structure. Furthermore, the solventless UV-curable polyurethane acrylate (PUA), employed as the membrane material, has lower surface energy leading to much better anti-biofouling performance than other commercial membrane materials. The soft-lithographic technique and UV-curable polyurethane acrylate (PUA) introduced here would open a horizon to a new generation of membranes with anti-fouling capability.