Synthesis, characterization and physical-chemical properties of room temperature ionic liquids with a variety of cations, paired with bis(trifluoromethylsulfonyl)imide anion

This thesis contains two main parts: synthesis of ionic liquids and their precursors, and measurement of the physical-chemical properties of the ionic liquids synthesized. The first part describes a study of the successful synthesis of 22 ionic liquids and their precursors, including 12 novel compou...

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Bibliographic Details
Main Author: Ab Rani, Mohd Azri
Other Authors: Welton, Tom ; Lickiss, Paul
Published: Imperial College London 2012
Subjects:
Online Access:http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.566370
Description
Summary:This thesis contains two main parts: synthesis of ionic liquids and their precursors, and measurement of the physical-chemical properties of the ionic liquids synthesized. The first part describes a study of the successful synthesis of 22 ionic liquids and their precursors, including 12 novel compounds ([RC1im][X] and [RC1pyrr][X] where R=C4, C5, C2OC2C1, SiOSiC1, (SiO)2SiC1, X=Cl, NTf2). In this study a reliable and rigorous method for the synthesis of ionic liquids in a good yield and high quality was developed. The ionic liquids synthesized contained a variety of cations containing alkyl, ether, disiloxane and trisiloxane side chains. All the ionic liquids contained the bis(trifluoromethylsulfonyl) imide anion. The second part of the project was the study of the physical-chemical properties of the ionic liquids synthesized. Understanding these physical-chemical properties is required before any applications can proceed. The polarity, density, thermal stability, viscosity, conductivity and diffusion coefficients of the ionic liquids were measured and described. The Kamlet-Taft [Symbol appears here. To view, please open pdf attachment] values of the ionic liquids are dominated by the nature of cations whereas the β values are controlled by the nature of the anion. The polarizability values, π* were lowered by having siloxane side chains in comparison to alkyl and ether side chains. Ionic liquids with an ether side chain showed the highest density of those studied. The thermal stabilities of the ionic liquids followed the order alkane > ether > disiloxane > trisiloxane substituent. From a transport property point of view, it can be concluded that the less viscous the ionic liquids, the faster the movement and higher the diffusion coefficient of the ions.