الفهرس 
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Abstract
Membranes have wide uses in industry and medicine applications. Polymer membranes are important materials because of their high chemical resistance, but they are of weak mechanical resistance against high pressures during applications or permeability measurements. Therefore, it was essential to modify a permeability measuring technique free from application of high pressure. The current work represents a modification for the permeability measuring technique of membranes, where ionic salt has been added with known concentration to water as common solvent and the electrolyte current has been measured behind the membrane. The electrolysis current has been correlated to the flow rate of water across a polyvinyl alcohol (PVA) membrane. When some problems have been raised such as polarization on electrodes and changes in electrolyte contents during the long time of the slow process; pulsed potential on electrodes has been used to resolve these problems .Other emerged problems such as rush in current and the double layer capacitance effect have been solved by software control of pulse amplitude and duration. An empirical equation was suggested to evaluate the permeability of polymer membranes by this modified method. Moreover, easy and accurate measurement of permeability have facilitated the study of changing the permeability of PVA membranes by adding copper nano-particles (5% to 20%) in membrane to reduce its permeability, and adding silicone dioxide micro particles (5% and 10 %) to the PVA membranes to increase its permeability. It’s worth noting that the addition of silicon dioxide micro-particles more than 10% has reduced the permeability. The mechanism for this behaviour has been suggested and verified from images by the scanning electron microscope (SEM).