What causes the low viscosity of ether-functionalized ionic liquids? Its dependence on the increase of free volume
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...
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sg-ntu-dr.10356-972402020-03-07T11:35:37Z What causes the low viscosity of ether-functionalized ionic liquids? Its dependence on the increase of free volume Chen, Zhengjian Xue, Tong Lee, Jong-Min School of Chemical and Biomedical Engineering 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. 2013-06-25T02:06:48Z 2019-12-06T19:40:30Z 2013-06-25T02:06:48Z 2019-12-06T19:40:30Z 2012 2012 Journal Article 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. 2046-2069 https://hdl.handle.net/10356/97240 http://hdl.handle.net/10220/10573 10.1039/c2ra21772d en RSC advances © 2012 The Royal Society of Chemistry. |
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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. |
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School of Chemical and Biomedical Engineering |
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School of Chemical and Biomedical Engineering Chen, Zhengjian Xue, Tong Lee, Jong-Min |
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Chen, Zhengjian Xue, Tong Lee, Jong-Min |
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Chen, Zhengjian Xue, Tong Lee, Jong-Min What causes the low viscosity of ether-functionalized ionic liquids? Its dependence on the increase of free volume |
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Chen, Zhengjian |
title |
What causes the low viscosity of ether-functionalized ionic liquids? Its dependence on the increase of free volume |
title_short |
What causes the low viscosity of ether-functionalized ionic liquids? Its dependence on the increase of free volume |
title_full |
What causes the low viscosity of ether-functionalized ionic liquids? Its dependence on the increase of free volume |
title_fullStr |
What causes the low viscosity of ether-functionalized ionic liquids? Its dependence on the increase of free volume |
title_full_unstemmed |
What causes the low viscosity of ether-functionalized ionic liquids? Its dependence on the increase of free volume |
title_sort |
what causes the low viscosity of ether-functionalized ionic liquids? its dependence on the increase of free volume |
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2013 |
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https://hdl.handle.net/10356/97240 http://hdl.handle.net/10220/10573 |
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