A method for producing Nafion(R) powder from commercially available pellets, and using this powder to produce membranes, is described. A description of particle size distribution, chemical composition, and thermal properties of Nafion(R) powders prepared by high-energy ball milling of pellets is given. Nafion(R) powders prepared in this manner exhibit thermal behavior similar to that of the precursor pellets; however, traces of iron from the milling materials are shown to be present through transmission electron microscopy analysis of the particles. The membranes prepared by hot pressing of the Nafion(R) powders also show thermal behavior similar to that of the precursor pellet materials. (C) 2004 Wiley Periodicals, Inc.