Lynette Anne Makins Holland

Ionic liquids as modulators of fragrance release in consumer goods

When organic esters or alcohols were dissolved in each of three novel ionic liquids (which have no effective vapour pressure), the vapour–liquid equilibria (as measured by infrared spectroscopy of the gas phase) revealed significant positive deviation from Raoults law for a wide range of perfume raw materials. The addition of water amplified the repulsive effect of the ionic liquid matrix, and this was exemplified by a series of ternary phase diagrams.

Delayed release of a fragrance from novel ionic liquids

When organic molecules are dissolved in ionic liquids (which have no effective vapour pressure), the vapour–liquid equilibria (as measured by infrared spectroscopy of the gas phase) revealed significant deviation from Raoults law for a wide range of perfume raw materials. Previously, we had demonstrated a positive deviation from Raoults law, enhancing the vapour pressure of the organic components. Here we developed a designed strategy for the ionic liquids which induces a negative deviation from Raoults law, hence depressing the vapour pressure of the organic solutes.

A New Technique for Studying Vapour–liquid Equilibria of Multi-Component Systems

A Fourier transform infrared gas-phase method is described herein and capable of deriving the vapour pressure of each pure component of a poorly volatile mixture and determining the relative vapour phase composition for each system. The performance of the present method has been validated using two standards (naphthalene and ferrocene), and a Raoult’s plot surface of a ternary system is reported as proof-of-principle. This technique is ideal for studying solutions comprising two, three, or more organic compounds dissolved in ionic liquids as they have no measurable vapour pressures.