in 150 ml of a 3 0 mol liter potassium chloride aqueous solution and titrated with 0 01 mol liter potassium hydroxide aqueous solution for 24 hours at room temperature from the measured volume v liter of the potassium hydroxide aqueous solution required for the neutralization titration the ion exchange capacity e of the membrane was calculated according to the following expression for sample c the measurement of the ion exchange capacity is 0 05 milliequivalent g the above measured ion exchange capacity of the membrane indicates that not all u2014 so 3 h groups available from the sulfonating agent are effective in bonding to the syndiotactic polystyrene through the sulfonation this is however advantageous since according to the invention the ionic groups u2014 so 3 h groups are introduced and regularly spaced into the crystalline regions only along the pathways interested by the ion transport this results in good electrical conductivity of the membrane to measure the electrical conductivity of the membrane the membrane sample c was immersed in distilled water for 2 hours at room temperature and then after water attached on surface of the membrane it was wiped off and the electrical conductivity of membrane was measured membrane conductivity was determined from a lateral resistance of the membrane that was measured using a four point probe electrochemical impedance spectroscopy technique a bekktech conductivity cell was used to.