The membrane was modified using a sequential two-step procedure. In the first step, the membrane was made hydrophobic by treatment with NH2-PDMS-NH2 (3% w/v) solution in an isopropanol-DMF mixture (95:5 v/v). In the second step, the hydrophobic membrane was treated with H3CO-PEG-NCO (5%, w/v, in isopropanol) for 48 h at 50 °C. H3CO-PEG-NCO was synthesized beforehand. Its synthetic procedure and life cycle inventory are shown in Fig. and Table . Sequential surface modification formed a partially crosslinked amphiphilic network on the membrane.