Effect of polymers blend ratio binder on electrochemical and morphological properties of PC/S‐PVC‐based heterogeneous cation‐exchange membranes

In this research, heterogeneous cation exchange membranes were prepared by the casting‐solution technique using polycarbonate (PC) and S‐polyvinylchloride (S‐PVC) as binders along with cation exchange resin as functional group agent. The effect of blend ratio (PC to S‐PVC) of polymer binder on structure and electrochemical properties of the prepared membranes were elucidated. The morphology of the prepared membranes was investigated by scanning electron microscopy (SEM) and scanning optical microscopy (SOM). The images show that the addition of PC ratio in the casting solution results in formation of a membrane with more inner cavities and micro voids. The electrochemical properties and mechanical strength tests were conducted. Water content, ion exchange capacity, ion permeability, flux, current efficiency, and oxidative stability of the prepared membranes initially were decreased by increasing the PC ratio in the casting solution and then it began to increase. The blending of S‐PVC and PC polymers results in membranes with lower mechanical strength. Membrane potential, surface charge density, perm‐selectivity, cationic transport number, electrical resistance, and energy consumption were initially improved by the increment of PC ratio in the casting solution and then it decreased. The membrane with 70% PC exhibited the highest flux, maximum current efficiency, and minimum energy consumption. However, the selectivity of this membrane was low compared with the other prepared membranes. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011