Please use this identifier to cite or link to this item:
|Title:||Synthesis, cross-linking modifications of 6FDA-NDA/DABA polyimide membranes for ethanol dehydration via pervaporation|
|Keywords:||6FDA-NDA/DABA polyimide membrane|
|Source:||Le, N.L., Wang, Y., Chung, T.-S. (2012-10-01). Synthesis, cross-linking modifications of 6FDA-NDA/DABA polyimide membranes for ethanol dehydration via pervaporation. Journal of Membrane Science 415-416 : 109-121. ScholarBank@NUS Repository. https://doi.org/10.1016/j.memsci.2012.04.042|
|Abstract:||A novel polyimide, copoly(1,5- naphthalene/3,5-benzoic acid-2,2'-bis(3,4-dicarboxyphenyl) hexafluoropropanedimide (6FDA-NDA/DABA), has been synthesized and modified via various cross-linking modifications for ethanol dehydration as a pervaporation membrane. Three different cross-linking approaches - thermal, diamino and diol cross-linking modifications - are employed; their effects on membrane morphology and separation performance are investigated with the help of various characterization techniques. Thermal treatment at high temperature (425 °C) facilitates the decarboxylation-induced cross-linking, therefore restricting the membrane swelling, creating a higher d-space among polymer chains, and contributing to high permeation fluxes and comparable separation factors of the resultant membranes for ethanol dehydration. Diamino cross-linking modification changes imide groups in the polyimide into amide groups but post heat-treatment converts them back. However, the interactions among polymer chains are irreversibly changed by the formation of chemical cross-linking and charge transfer complexes, as well as the enhanced hydrophilicity, which bring out the improvement in membrane performance. Diol cross-linking also constrains the membrane swelling and results in a higher d-space by the cross-linking spacer, and therefore leading to a higher flux but a lower separation factor than membranes modified by the above two other methods. This work may provide useful insights for polyimide synthesis and cross-linking modifications for biofuel separation. © 2012 Elsevier B.V.|
|Source Title:||Journal of Membrane Science|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Feb 12, 2018
WEB OF SCIENCETM
checked on Feb 12, 2018
checked on Feb 20, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.