Polymeric and activated carbon composite membranes were prepared and their morphology quantitatively, tensile properties and performance (flux and cut-off) were characterized. Both types of membranes were prepared by using polysulfone and di-methyl formamide as polymer and solvent, respectively. In order to obtain a wide range of morphologies, two non-solvents were used (water and iso-propanol) and eight coagulation baths were produced by using the non-solvents alone, by mixing them and by mixing each one with the solvent. Numerical values for the main morphological properties of the membrane were determined from micrographs obtained by scanning electron microscopy, atomic force microscopy and IFME (R) software. The tensile properties were also determined. Finally, the performance of the membranes in terms of flux and cut-off was determined. Results show that varying the coagulation bath can lead to a wide range of morphologies and cut-off. In the range studied, the presence of activated carbon on the membranes does not significantly change the properties studied. Neither the morphology nor the tensile properties are significantly modified. Finally, the presence of water in the coagulation bath very clearly determines the tensile properties of membranes. (c) 2006 Elsevier B.V. All rights reserved.