Stability of Properties of a Modified Anion-Exchange Membrane Obtained by Treating the Surface of a Commercial Sample with Bifunctional Polymer Containing Quaternary Amino Groups

Modification of commercial ion-exchange membranes is the easiest and cheapest way to improve their properties. It has been shown that the treatment of the surface of the MA-41P membrane with a bifunctional polymer (copolymer based on polydiallyldimethylammonium chloride) not only reduces the generation of H+ and OH- ions but also contributes to an increase in the limiting current density and a reduction in the length of the current-voltage curve plateau compared to the initial membrane. These changes are signs of increased electroconvection at the surface of the modified membrane (MA-41PM). It has been found that the modified membrane exhibits stability for at least 100 h of operation in an overlimiting current mode. In an electric field, a partial separation of the modifier from the MA-41PM surface takes place as a result of which the rate of generation of H+/OH- ions gradually increases.