title: Anion conductive block poly(arylene ether)s: synthesis, properties, and application in alkaline fuel cells.
abstract: Anion conductive aromatic multiblock copolymers, poly(arylene ether)s containing quaternized ammonio-substituted fluorene groups, were synthesized via block copolycondensation of fluorene-containing (later hydrophilic) oligomers and linear hydrophobic oligomers, chloromethylation, quaternization, and ion-exchange reactions. The ammonio groups were selectively introduced onto the fluorene-containing units. The quaternized multiblock copolymers (QPEs) produced ductile, transparent membranes. A well-controlled multiblock structure was responsible for the developed hydrophobic/hydrophilic phase separation and interconnected ion transporting pathway, as confirmed by scanning transmission electron microscopic (STEM) observation. The ionomer membranes showed considerably higher hydroxide ion conductivities, up to 144 mS/cm at 80 °C, than those of existing anion conductive ionomer membranes. The durabilities of the QPE membranes were evaluated under severe, accelerated-aging conditions, and minor degradation was recognized by (1)H NMR spectra. The QPE membrane retained high conductivity in hot water at 80 °C for 5000 h. A noble metal-free direct hydrazine fuel cell was operated with the QPE membrane at 80 °C. The maximum power density, 297 mW/cm(2), was achieved at a current density of 826 mA/cm(2).
authors.affiliation: Fuel Cell Nanomaterials Center, University of Yamanashi, 4 Takeda, Kofu 400-8510, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Tanaka
authors.forename: Keita
authors.initials: K
authors.lastname: Fukasawa
authors.forename: Eriko
authors.initials: E
authors.lastname: Nishino
authors.forename: Susumu
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Koji
authors.initials: K
authors.lastname: Yamada
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Tanaka
authors.forename: Byungchan
authors.initials: B
authors.lastname: Bae
authors.forename: Kenji
authors.initials: K
authors.lastname: Miyatake
authors.forename: Masahiro
authors.initials: M
authors.lastname: Watanabe