| 摘要 |
<p>A composite ionomeric membrane comprising a layer or film of a porous inert material on which a (per)fluorinated sulphonic ionomer is deposited wherein the sulphonic groups are at the end of short side chains (SSC), said ionomer having: equivalent weight comprised between 280 and 1,700 g/eq; side chains of formula: -O-CF 2 -CF 2 -SO 3- M + , wherein M is hydrogen or an alkaline metal;
said membrane having in each of the two orthogonal directions xy of the plane, after dipping in demineralized water at 100°C for 30 minutes and preliminary drying at 105°C under vacuum for one hour, the following size variations: in one direction, size variation lower than 25%; in the other direction, size variation lower than 20%.</p> |
