Approaches to the Modification of Perfluorosulfonic Acid Membranes.

Polymer ion-exchange membranes are featured in a variety of modern technologies including separation, concentration and purification of gases and liquids, chemical and electrochemical synthesis, and hydrogen power generation. In addition to transport properties, the strength, elasticity, and chemical stability of such materials are important characteristics for practical applications. Perfluorosulfonic acid (PFSA) membranes are characterized by an optimal combination of these properties.

Correlation between Nafion Morphology in Various Dispersion Liquids and Properties of the Cast Membranes.

Nafion is a perfluorosulfonic acid polymer that is most commonly used in proton-exchange membrane fuel cells. The processes of pretreatment and formation of such membranes strongly affect their properties. In this work, dispersions of Nafion in various ionic forms and dispersing liquids (ethylene glycol, -dimethylformamide, -methyl-2-pyrrolidone and isopropyl alcohol-water mixtures in different ratios) were obtained and studied.

On the Properties of Nafion Membranes Recast from Dispersion in -Methyl-2-Pyrrolidone.

Perfluorosulfonic acid Nafion membranes are widely used as an electrolyte in electrolysis processes and in fuel cells. Changing the preparation and pretreatment conditions of Nafion membranes allows for the optimization of their properties. In this work, a Nafion-NMP membrane with a higher conductivity than the commercial Nafion 212 membrane (11.

Membranes Based on Polyvinylidene Fluoride and Radiation-Grafted Sulfonated Polystyrene and Their Performance in Proton-Exchange Membrane Fuel Cells.

Proton-exchange membranes based on gamma-irradiated films of PVDF and radiation-grafted sulfonated polystyrene with an ion-exchange capacity of 1.8 meq/g and crosslinking degrees of 0 and 3% were synthesized. A solvent-free, environmentally friendly method of styrene grafting from its aqueous emulsion, with a styrene content of only 5 vol.