108.Enhanced thermal stability of organogels through self-reinforcing supramolecular assembly of a cholesterol–polyoxomatalate–cholesterol hybrid gelator
writer：Hai-Kuan Yang,? Ming-Ming Su,? Li-Jun Ren, Ping Zheng and Wei Wang
keywords：polyoxomatalate，cholesterol，organogel，self-reinforcing
source：期刊
specific source：RSC Adv., 2014, 4, 1138–1145
Issue time：2013年
We report our study on the enhanced thermal stability of organogels through forming self-reinforcing supramolecular assemblies of a polyoxometalate (POM)-containing hybrid gelator. The designed and synthesized gelator has a molecular structure of cholesterol–POM–cholesterol. In our experiment, we found an intriguing phenomenon: the hybrid gelator could dissolve in toluene at 80 C and the solutions became immobilized when cooled to room temperature, that is, organogels formed. However, the toluene organogels could not be converted into the solutions when they were reheated to 80 C or an even higher temperature like 120 C, which is ca. 10 C higher than the boiling point (110.8 C) of
toluene. This result reveals that the organogels of the hybrid gelator have a high thermal stability. We demonstrated that the rationally designed hybrid gelator assembled in its toluene organogel into a single-molecule-layer nanoribbon, within which an orderly POM layer was sandwiched between the two cholesterol layers. This ordered structure could maximize the interactions of the POM clusters, so the POM layer was found to profoundly reinforce the nanoribbons and the cholesterol layers were considered to produce the nanoribbons with good compatibility with toluene. In this way, the thermal stability of this hybrid organogel in toluene was greatly enhanced.