Patent ID: 6514561
Filing Date: 2003-02-04
Classification: C08J

Abstract:
Method of manufacturing an electrolytic membrane comprising:a) forming a solution by dissolving an ion-conducting polymer in a solvent, at least 25% by weight of which is composed of a component having a boiling point higher than 125Â° C., b) applying an amount of the solution prepared under (a) to a horizontal polyalkene membrane having an upper side and an underside stretched in at least one direction and having a pore volume of 30-90% of the total volume of the membrane, the amount of the solution being chosen in such a way that the volume of the ion-conducting polymer present therein is more than 60% of the pore volume, and the membrane being sealed at the underside, c) evaporating the solvent at a temperature which is at least 80Â° C. and which is lower than the melting point of the polyalkene membrane; wherein said electrolytic membrane comprises the ion-conducting polymer fixed in pores of the polyalkene membrane whose porosity is 30-90% by volume, wherein the polyalkene membrane is stretched in at least one direction, has a mean pore size between 0.1 and 5 &mgr;m, and has a current density of at least 0.5 A/cm2 at a cell voltage of 0.6 V using air as oxidant.