Please use this identifier to cite or link to this item: https://hdl.handle.net/10356/97240
Title: What causes the low viscosity of ether-functionalized ionic liquids? Its dependence on the increase of free volume
Authors: Chen, Zhengjian
Xue, Tong
Lee, Jong-Min
Issue Date: 2012
Source: Chen, Z., Xue, T., & Lee, J.-M. (2012). What causes the low viscosity of ether-functionalized ionic liquids? Its dependence on the increase of free volume. RSC advances, 2(28), 10564-10574.
Series/Report no.: RSC advances
Abstract: A series of 12 ether-functionalized room temperature ionic liquids (RTILs) and their alkyl counterparts (short of an oxygen atom) were prepared and characterized to investigate the reason for the alkoxy chain effect on decreasing viscosity and how to best apply it. In addition to the ability of the alkoxy chains to decrease viscosity (ηO/η, as low as 0.594) and its activation energy (ΔEη, as low as -4.14 kJ mol−1), they were also found to be able to increase the total free volume (ΔFVO, up to 4.93 mL mol−1), by using density and surface tension. Furthermore, both the obtained ηO/η and ΔEη values for the 12 pairs of RTILs show a strong decreasing dependence on ΔFVO. Accordingly, the reason for the alkoxy chain effect on decreasing viscosity was proposed to be due to the ability of the highly flexible alkoxy chains to increase the total free volume, which offers the convenience of transport for the adjacent molecules. To maximize this effect, the alkoxy groups were supposed to contain a rod-like alkyl tail and a short –CH2– spacer between the ether O atom and the cationic N atom, and be in an environment without hydrogen bond donors. Generally, the ether-functionalized pyrrolidinium and ammonium RTILs possess high conductivity (up to 4.97 mS cm−1 at 25 °C) and wide electrochemical windows (~5.75 V), indicating their significant promise for electrochemical applications.
URI: https://hdl.handle.net/10356/97240
http://hdl.handle.net/10220/10573
ISSN: 2046-2069
DOI: 10.1039/c2ra21772d
Rights: © 2012 The Royal Society of Chemistry.
Fulltext Permission: none
Fulltext Availability: No Fulltext
Appears in Collections:SCBE Journal Articles

Google ScholarTM

Check

Altmetric


Plumx

Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.