Enhancement of Styrene Adsolubilization and Solubilization by Rhamnolipid Biosurfactant‐Linker Mixtures onto an Aluminum Oxide Surface

Abstract

The polarity of rhamnolipid, a relatively hydrophilic biosurfactant, can be enhanced by the addition of linker molecules. In this work, rhamnolipid biosurfactant-modified surfaces were prepared with and without a combination of linkers (1-butanol, 1-octanol, and 1-dodecanol) to investigate effects of linker molecules on styrene adsolubilization and solubilization. Results showed that styrene adsolubilization increased with increasing carbon chain lengths of the linker molecules whereas the solubilization of styrene exhibited the opposite effect. Decreasing the carbon atoms in the linker molecules resulted in higher styrene solubilization capacity because of the change in polarity of the three-dimensional surfactant aggregates. The higher adsolubilization capacity indicated the enlargement of surfactant tails that was created a larger adsolubilization region in the admicelle while the lesser solubilization of styrene indicated the decreasing of affective area per molecule of the surfactant-linker system (butanol [ octanol [ dodecanol).

Anionic and Cationic Surfactant Synergism: Minimizing Precipitation, Microemulsion Formation, and Enhanced Solubilization and Surface Modification

“…When surfactant concentration exceeds its CMC, the surfactant monomer concentration becomes constant and no additional adsorption occurs with further increasing surfactant concentrations as a result of the plateau adsorption (Region IV). Partitioning of the compounds into the admicelle can be quantitatively described by the admicellar partition coefficient (K adm ) through adsolubilzation studies, as described elsewhere (Charoensaeng et al, 2008;Fuangswasdi et al, 2006;Rosen and Kunjappu, 2004).…”