Volatile surfactants: Characterization and areas of application

Investigating the Vapor-Phase Adsorption of Aroma Molecules on the Water–Vapor Interface using Molecular Dynamics Simulations

“…Conversely, volatile surfactants that can adsorb onto the V–L interface via vapor-phase diffusion have been less explored. , The ability to adsorb from the vapor-phase and tune the V–L interfacial tension is not only convenient for some applications but also has the potential to expand the use of these additives to new areas. A related application can be the Marangoni condensation , of a binary mixture of water and ethanol vapors, which yields a pseudodropwise condensation mode with high heat transfer coefficients (HTC), even on hydrophilic surfaces.…”

“…Dispensing surfactant molecules in the vapor phase can be realized conveniently with volatile surfactants, such as aroma molecules exhibiting amphiphilic properties. ,, Such behavior is primarily attributed to their polar hydrophilic group (hydroxyl, acetate) and an unsaturated hydrophobic tail comprising either a small aliphatic chain (linalool, geraniol, nerol, and citral, among others) or the aromatic ring (benzyl alcohol, benzyl acetate). These molecules have low molecular weights and are liquid at room temperature.…”

“…These molecules have low molecular weights and are liquid at room temperature. Their molecular structure enables them to have lower boiling points between ∼198 and 230 °C and high vapor pressures at room temperature between ∼1.1 and 213.3 Pa, compared to typical surfactants such as SDS with a boiling point of ∼288 °C . This relatively high vapor pressure of aroma molecules makes them suitable surfactants for fragrance manufacturing .…”

“…This relatively high vapor pressure of aroma molecules makes them suitable surfactants for fragrance manufacturing . Further, most of these molecules are nonmicellar and exhibit higher stability at the air–water interface with a sharper reduction in surface tension …”

“…A comparative study on the physical properties of different volatile aroma molecules shows that linalool, with a molecular structure C 10 H 18 O and weight 154.25 g/mol, has a relatively low boiling point and high vapor pressure at room temperature. Accordingly, linalool is often considered as the candidate volatile surfactant for tuning the water/liquid interfaces by vapor phase adsorption in envisaged applications.…”