Characterization of porous structure through the dynamical properties of ions confined in sulfonated polyimide ionomers films

• Published in: The European physical journal. E, Soft matter and biological physics Vol. 12 Suppl 1; no. S1; pp. S131 - 134
• Main Authors: Rollet, A-L, Blachot, J-F, Delville, A, Diat, O, Guillermo, A, Porion, P, Rubatat, L, Gebel, G
• Format: Journal Article
• Language: English
• Published: France 01.11.2003
• ISSN: 1292-8941; 1292-895X
• DOI: 10.1140/epjed/e2003-01-030-4

The structure of sulfonated PolyImide (sPI) ionomer membrane has been investigated via the transport properties of ions confined inside. Transport coefficients of N(CH(3))(4)(+) and Na(+) ions have been determined by several techniques in order to get a range of time/space scale as wide as possible: a method using radiotracers, conductivity, pulsed field gradient NMR and NMR quadrupolar relaxation rates determination. For N(CH(3))(4)(+), the self-diffusion has been measured in the direction of membrane plan (parallel) and in the perpendicular direction (transverse), whereas for Na(+) only transverse self-diffusion has been measured. The conductivity of both ions has been measured in the transverse direction. The results show a anisotropic and multiscale structure with a separation phase between hydrophilic and hydrophobic domains that is not well-defined.