A series of multiblock copolymers including poly(arylene ether)s and poly(norbornenes) with long head-group tethers were synthesized for use in AEM fuel cells and electrolyzers. In this study, the number of head-groups per block and resulting conductivity, domain size and water uptake was studied. The improvement in performance (increased conductivity and reduced water uptake) was correlated with domain size, bound and unbound water content, and ion channel configuration.
Financial support for L.L. and J.M.A. from US Office of the Deputy Assistant Secretary of the Army for Defense Exports and Cooperation (DASA-DE&C) is gratefully acknowledged. Financial support for M.M. from ARPA-E Ionics program is gratefully acknowledged.