Membranes M1 and M2 were individually used to separate an oil-in-water emulsion using a crossflow-filtration setup. The initial permeate fluxes through the membranes are 326 L m -2 h -1 (M1) and 348 L m -2 h -1 (M2) at 0.35 bar (Fig. ). After filtering the oil-in-water emulsion, M1 shows ~16% FR and >99% FRR, while M2 shows ~22% FR and ~ 99% FRR (Fig. ). Thus, both membranes perform comparable oil-water separation. The low FR of M1 results from its hierarchical globular surface morphology and the high grafting density of PEI; the hydrated PEI chains and rough surface morphology render the M1 surface superhydrophilic . The low FR of M2 could be due to a partially crosslinked network of dangling PDMSlinked PEG on its surface. Fouling release by the low-surface-energy PDMS reduces the van der Waals interaction between the foulants and the M2 surface, while the hydrated PEG chains minimise hydrophobic interactions, enhancing the cleaning effect .