Enhanced thermal stability of organogels through self-reinforcing supramolecular assembly of a cholesterol–polyoxomatalate–cholesterol hybrid gelator
Enhanced thermal stability of organogels through self-reinforcing supramolecular assembly of a cholesterol–polyoxomatalate–cholesterol hybrid gelator
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DOI：
10.1039/c3ra45550e
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发表时间：
2014
期刊：
影响因子：
3.9
通讯作者：
Haikuan Yang;Mingxing Su;Li-jun Ren;Ping Zheng;Wei Wang
中科院分区：
文献类型：
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作者：
Haikuan Yang;Mingxing Su;Li-jun Ren;Ping Zheng;Wei Wang
我们报告了通过形成含有多金属氧酸盐（POM）的杂化胶凝剂的自增强超分子组装体来增强有机凝胶热稳定性的研究。设计合成的凝胶剂具有胆固醇-POM-胆固醇的分子结构。在我们的实验中，我们发现了一个有趣的现象：混合胶凝剂可以在80℃下溶解在甲苯中，当冷却到室温时溶液变得固定，即形成有机凝胶。然而，当将甲苯有机凝胶重新加热到80℃或更高的温度（例如120℃）时，甲苯有机凝胶无法转化为溶液。比甲苯的沸点（110.8℃）高10℃。该结果表明混合凝胶剂的有机凝胶具有高热稳定性。我们证明了合理设计的混合胶凝剂在其甲苯有机凝胶中组装成单分子层纳米带，其中有序的 POM 层夹在两个胆固醇层之间。这种有序结构可以最大化POM簇的相互作用，因此发现POM层可以深刻地增强纳米带，而胆固醇层被认为可以产生与甲苯具有良好相容性的纳米带。通过这种方式，这种杂化有机凝胶在甲苯中的热稳定性大大增强。
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.