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N. C. Osti, T.N. Etampawala, U.M. Shrestha, D. Aryal, Madhu Sudan Tyagi, S. O. Diallo, E. Mamontov, C. J. Cornelius, D. Perahia
Abstract
The dynamics of water within ionic polymer networks formed by sulfonated poly(phenylene) (SPP), as revealed by quasi-elastic elastic neutron scattering (QENS), is presented. These polymers are distinguished from other ionic macromolecules by their rigidity and therefore in their network structure. QENS measurements as a function of temperature as the fraction of ionic groups and humidity were varied have shown that the polymer molecules are immobile where adsorbed water remain dynamic. The water molecules occupy multiple sites, either free or bound, and jump between these two types of sites. With increasing temperature and hydration levels, the system becomes more dynamic. Water remains mobile even at subzero temperatures, illustrating the applicability of SPP membrane for selective transport over a broad temperature range.
Osti, N.
, Etampawala, T.
, Shrestha, U.
, Aryal, D.
, Tyagi, M.
, Diallo, S.
, Mamontov, E.
, Cornelius, C.
and Perahia, D.
(2016),
Water Dynamics in Rigid Ionomer Networks, Journal of Chemical Physics, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=921925
(Accessed October 11, 2025)