Appears in Journal of Physical Chemistry
MURRAY, Ky. (Sept. 19, 2014) — Researchers in the chemistry department at Murray State University recently published a paper describing the essential physical and thermal properties of a new class of ionic liquids.
Traditional ionic materials, such as sodium chloride (table salt), exist as solids at room temperature and display high melting points. Ionic liquids, however, rely on larger positively charged species called cations and negatively-charged species called anions. Cations and anions do not “pack” effectively into a crystalline lattice, which is the arrangement of atoms that are found in crystals. The result of not “packing” effectively is a material that prevails as a liquid at or near room temperature and has the potential to store or conduct an electrical current.
Over the last 15 years, ionic liquid research has increased in popularity with applications ranging from “green” reaction solvent replacements to conducting devices such as transducers and actuators, which are devices or motors that are operated by an electrical current. Materials containing ionic liquids have been used as components in these devices. Several ionic liquids have in fact been used as precursors for polymeric drug-delivery vehicles. Polymers are large molecules, many of which have the ability to coordinate with drugs and effectively “deliver” them into the body and/or into cells.
Senior chemistry major student Andreah De La Hoz and chemistry graduate student Ulises Gonzalez-Brauer are researching the ionic liquids under the direction of Dr. Kevin Miller, assistant professor in the department of chemistry at Murray State University.
As part of the study, a series of ionic liquids that contain a triazolium cation were prepared and their physical properties (density, viscosity and conductivity) were determined over a wide temperature range. Thermal properties such as melting points and thermal stabilities were also determined using instrumentation in the Polymer and Materials Characterization Lab in the Jesse D. Jones Chemistry Building at Murray State.
The results of the study found a direct correlation between the trizolium cation structure and many of these physical and/or thermal properties. The publication explains in-depth the first study of this class of ionic liquids. The research article can be found in the Journal of Physical Chemistry, Part B.
Miller hopes that this research will catalyze additional studies in his lab as well as collaborations with other research groups. “Research projects such as this one are giving students like Andreah and Ulises the opportunity to engage in ‘hands-on’ laboratory training that will be valuable in their careers beyond graduation,” said Miller. “Research experience is becoming a requirement for many graduate and medical schools as well as for prospective employers, so having students get their hands wet in a research lab makes them more competitive than students at larger institutions where such experiences are often not available. Additionally, since ionic liquid research is very popular and robust, publication of this work will give our program and Murray State the necessary visibility to develop collaborations with other scientists as well as attract additional funding.”
De La Hoz and Brauer plan on presenting their findings at the Southeast Regional Meeting of the American Chemical Society in October. Miller noted that acknowledgement is made to the donors of the American Chemical Society Petroleum Research Fund as well as the department of chemistry at Murray State University for financial support of this research.