Release Time:2019-03-09  Hits:

Indexed by: Journal Article

Date of Publication: 2014-06-01

Journal: JOURNAL OF MEMBRANE SCIENCE

Included Journals: Scopus、EI、SCIE

Volume: 459

Page Number: 86-95

ISSN: 0376-7388

Key Words: Hydroxide exchange membrane; 1,4-diazabicyclo [2,2,2] octane; Crosslinking; Ion concentration; Hydroxide conductivity

Abstract: Crosslinked poly (ether ether ketone) (PEEK) hydroxide exchange membranes are prepared using bifunctional cyclic ammonium, 1,4-diazabicyclo [2,2,2] octane (DABCO), as simultaneous quaternization and crosslinking reagent. Hydroxide conductivity and ion mobility are evaluated as a function of ion concentration, which integrates the counteracting effects of the hydroxide ion amount and crosslinking degree. With the increase of ion concentration, effective mobility of hydroxide ion increases to a high level and then levels off or slightly goes down, suggesting a balance existed between ion concentration and mobility in the crosslinked membranes. As a result, hydroxide conductivity increases rapidly to a high stable level, indicating the applicable range of ion concentration (up to 1.0 mol L-1) for improving hydroxide conductivity. The crosslinked membranes exhibit high hydroxide conductivity of 33.4 mS cm(-1) at 25 degrees C and low swelling ratio of 48.2% at 60 degrees C. Thermal stability (T-onset: 176 degrees C) of the crosslinked membranes is better as compared with the non-crosslinked (T-onset : 165 degrees C) and trimethylamine quaternized PEEK membranes., (C) 2014 Elsevier B.V. All rights reserved.