Influences of casting solvents on proton dynamics within sulfonated polyether ether ketones (S-PEEKs) studied using high-resolution solid-state NMR

Proton mobilities of S-PEEK membranes with variable degrees of sulfonation (DS), and of S-PEEK membranes cast from different solvents were studied using high-resolution solid-state 1H MAS NMR. In the hydrated S-PEEKs, a single resonance for water-associated sulfonic acid protons was observed for S-PEEK with DS=58 and 95%, which indicates that the acid protons in either of these S-PEEK samples have similar environments, suggesting a similar …