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Organic Structure-directing Agent-free Synthesis for *BEA-type Zeolite Membrane
Published on: February 22, 2020
Phosphonium-functionalized polyethylene: a new class of base-stable alkaline anion exchange membranes
Kevin J T Noonan1, Kristina M Hugar, Henry A Kostalik
1Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, USA.
Abstract:
A tetrakis(dialkylamino)phosphonium cation was evaluated as a functional group for alkaline anion exchange membranes (AAEMs). The base stability of [P(N(Me)Cy)(4)](+) was directly compared to that of [BnNMe(3)](+) in 1 M NaOD/CD(3)OD. The high base stability of [P(N(Me)Cy)(4)](+) relative to [BnNMe(3)](+) inspired the preparation of AAEM materials composed of phosphonium units attached to polyethylene. The AAEMs (hydroxide conductivity of 22 ± 1 mS cm(-1) at 22 °C) were prepared using ring-opening metathesis polymerization, and their stabilities were evaluated in 15 M KOH at 22 °C and in 1 M KOH at 80 °C.
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