Novel thermotropic gels composed of only ions

摘要

Novel thermotropic physical gels were synthesized by mixing different ionic liquids without reduction of ion density due to addition of no other additives such as polymer materials or gelators.rnRoom-temperature ionic liquids are attracting considerable attention as novel solvents for wide applications due to such properties as negligible vapour pressure, high thermal stability, and high ionic conductivity. Additionally, RTILs were expected as "designer solvents", because their properties such as viscosity, density, polarity and miscibility are tuneable by ion design. We have previously reported that amino acids can be used as anions by coupling with cations for ionic liquid preparation. Most of the 20 different amino acids became liquid at room temperature (R.T.) by coupling them with imidazolium cations or phosphonium cations. Since amino acid ionic liquids (AAILs) are halogen-free, having a chiral center and a variety of side chains, AAILs are expected to emerge as novel functional materials.