The capability of modifying ultrafiltration (UF) membranes with different base-polymers using a newly synthesized hydrophilic additive was investigated in this study. Five typical base-polymers were tested: cellulose acetate (CA), polyetherimide (PEI), polyethersulfone (PE-S), polysulfone (PS), and polyvinylidene fluoride (PVDF). The changes in characteristics mid performance of the membranes were analyzed using scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle analysis, mid solute transport tests. It was found that the effect of the hydrophilic additive was different for each polymer. Higher additive contents resulted in higher permeation flux. A visible effect oil water content mid permeability was obtained but the impact was not shown clearly in contact angles, possibly the additive's concentration was not sufficiently high at the surface. In term of flux enhancement the PES mid PVDF membranes benefited Hie most by the addition of the hydrophilic additive. (C) 2010 Wiley Periodicals Inc. J Appl Polym Sci 116: 2205-2215, 2010