Powerful low-molecular-weight gelators based on l-valine and l-isoleucine with various terminal groups

Abstract

Novel L-valine and L-isoleucine gelators, which have various terminal groups, such as an ester, carboxylic acid and carboxylate as well as different alkyl chain lengths between the terminal group and L-amino acid segment, were synthesized and their organogelation properties were examined in various organic solvents and oils. The organogelation properties significantly depended on the molecular structures of the L-amino acid, the length of the alkyl chains and hydrophilic–hydrophobic balance of the gelators. The FT-IR studies demonstrated that the driving forces for the organogel formation were the hydrogen bonding and van der Waals interactions, and the aggregation modes of the nanofibers depended on the solvents. Furthermore, it was found that these gelators were useful for the selective gelation of oils or fuels from oil/water mixtures.