In the current research, polyvinylchloride (PVC)/styrene-Butadiene-Rubber (SBR) blend heterogeneous cation exchange membranes were prepared by solution casting technique using tetrahydrofuran as solvent and cation exchange resin powder as functional groups agent. Potassium perchlorate was also employed as an additive in membrane fabrication. The effect of additive concentration in the casting solution on physicochemical properties of home-made membranes was studied. Sonication was used to help in appropriate dispersion of particles in the membranes matrix. SEM images showed uniform particles distribution and also relatively uniform surfaces for the membranes. Moreover, images revealed that addition of KClO4 in the casting solution led to an improvement in resin particles distribution in the membranes matrix. The increase of KClO4 loading in casting solution caused the increase of membranes water content. The ion exchange capacity, membrane potential, permselectivity and transport number of the membranes all were increased initially by the increase of additive concentration up to 8 wt.% and then they showed decreasing trend with higher additive content. Conversely, the ionic permeability and flux showed opposite trends. The areal electrical resistance of the membranes was initially enhanced with increase in additive concentration to 16 wt.% and then it began to decrease by more additive loading. (C) 2011 Elsevier B.V. All rights reserved.