Transformation from a heat-set organogel to a room-temperature organogel induced by alcohols

A unique transformation from a heat-set organogel to a room-temperature organogel induced by ethanol (EtOH) was reported here. When the system containing beta-cyclodextrin, 4,4'-isopropylidenediphenol, N, N-dimethylacetamide and LiCl was heated to the gelling temperature (T-gel), a heat-set organogel would be formed. In contrast, a semitransparent organogel (room-temperature organogel) could be obtained by injecting EtOH into the system at ambient temperature. In this transformation process, EtOH played a role in the formation of hydrogen bonds, which was critical for the self-assembly. The influence of other guest molecules, solvents and alcohols on this transformation was also investigated. These organogels were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction, thermal gravity analysis and differential thermal gravity. Further, the formation mechanism of the organogels was proposed based on the above measurements.