Electrochemical behavior of a new type of perfluorinated carboxylate membrane/platinum composite

A new type of ionomeric polymer-metal composite (IPMC) based on various compositions of perfluoroalkylacrylate-acryl acid copolymer with different types of counter cation has been synthesized by a radical copolymerization of fluoroalkylacrylate (FA) and acrylic acid (AA). Swelling behavior of the membranes was studied in deionized water as well as in aqueous single salt solutions (LiCl and NaCl). Swell of membrane increased with the increase in ionic content of the copolymer. Swell in deionized water was much higher than in aqueous single salt solution. To examine its performance as a new electroactive polymer, actuation force and displacement responses to DC and step voltage across the IPMC were measured. Results indicated that membranes prepared from 75/25 (FA/AA) (FA25) gave an adequate flexibility and proper hydrated state, allowing easy deflection toward the applied voltage. Surface morphology measurements (atomic force microscopy and scanning electron microscopy) showed that platinum particles are predominantly located at the surfaces. (c) 2005 Wiley Periodicals, Inc.