Document Type
Article
Publication Date
3-11-2010
Publication Title
Polymer
Abstract
Perfluorosulfonic acid (PFSA) ionomer membranes are ion-conducting polymers with high water sorption capacity and thermo-mechanical stability. The morphology of PFSA changes during sorption affecting the mechanical and physical properties of the membrane. In this work, we investigate the structure-property relationship in swollen PFSA membranes using three proposed nanostructural descriptions and determine Young's modulus of the membrane at a wide range of temperatures (−20–85°C) and water volume fractions (0–0.5) for these configurations. Comparing the mechanics-based models with experimental data we propose that ion-rich water domains in PFSA membrane are spherical at low water content, spherical with connecting channels at intermediate water content and cylindrical at high water contents. Furthermore, our findings indicate that the scaling behavior for Young's modulus of PFSA ionomers is similar to that of aerogels. This suggests, from a mechanics perspective, that aerogels and ionomers may have a similar interconnected porous nanostructure where some solid regions do not contribute to the mechanical load-bearing capacity.
Recommended Citation
Kusoglu, A., Karlsson, A. M., and Santare, M. H., 2010, "Structure-Property Relationship in Ionomer Membranes," Polymer, 51(6) pp. 1457-1464.
Version
Postprint
Publisher's Statement
NOTICE: this is the author’s version of a work that was accepted for publication in Polymer. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Polymer, 51, 6, (03-11-2010);
Volume
51
Issue
6