M. Ingratta, E. P. Jutemar, P. Jannasch
Mar 14, 2011
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0
Influential Citations
48
Citations
Journal
Macromolecules
Abstract
Graft copolymers with ionic backbones and hydrophobic fluorinated side chains have been prepared by using lithiated poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) as a macroinitiator for anionic polymerization of 4-fluorostyrene. After grafting of the poly(4-fluorostyrene) (PFS) side chains, the PPO backbone was selectively sulfonated using trimethylsilylchlorosulfonate under mild and controlled conditions. Microscopy of solvent cast membranes revealed copolymer self-assembly into remarkably regular and well-ordered morphologies which, depending on the molecular structure, included lamellar and cylindrical arrangements of the proton conducting ionic nanophases. Thermal analysis indicated separate glass transitions of the PFS and PPO phases, and high thermal degradation temperatures of the membranes at approximately 220 and 300 °C for the H+ and the Na+ forms, respectively. The proton conductivity of fully hydrated acidic membranes was similar to that of Nafion, reaching above 0.2 S cm−1 at 120 °C. Compared ...