Release Time:2019-03-12  Hits:

Indexed by: Journal Article

Date of Publication: 2017-08-07

Journal: JOURNAL OF MATERIALS CHEMISTRY A

Included Journals: Scopus、EI、SCIE

Volume: 5

Issue: 29

Page Number: 15038-15047

ISSN: 2050-7488

Abstract: A novel alkaline group, hexamethylenetetramine (HMTA) with four tertiary amine groups and beta-hydrogenabsent structure, has been employed as mono-quaternization reagent to prepare HMTA mono-quaternized polysulfone anion exchange membranes (PSF-QuOH AEMs). Analyzed by molecular dynamics simulations, mono-quaternized HMTA shows a superior aggregating ability by strong electrostatic interaction with hydroxide to suppress water swelling even at high IECs. In particular, the PSF-QuOH membrane with a high IEC of 2.23 mmol g(-1) exhibits a low swelling ratio of 21% even at 60 degrees C. The resulting high concentration of cationic groups and the interactions between multiple hydrogen atoms in HMTA and hydroxide/water are helpful to induce the formation of the continuous and efficient hydrogen-bond networks, promoting ionic transport. High hydroxide conductivity of 35 mS cm(-1) is achieved at 20 degrees C. Excellent swelling resistance also benefits the mechanical and chemical stabilities of the PSF-QuOH membranes. A considerable mechanical strength of 17.7 MPa is observed in the fully hydrated membrane. The hydroxide conductivity is stable at around 86% of the initial value after 1 M KOH immersion at 60 degrees C for 168 h.