화학공학소재연구정보센터
Macromolecules, Vol.46, No.11, 4235-4246, 2013
Chiral Packing of Cholesteryl Group as an Effective Strategy To Get Low Molecular Weight Supramolecular Hydrogels in the Absence of Intermolecular Hydrogen Bond
Although the most commonly reported low molecular weight hydrogelators (LMWG) are based on the strong and highly directional hydrogen bond between polar groups, the expansion of novel species of LMWG is quite necessary to fulfill different requirements of practical applications. Herein, we demonstrated that using an inherently chiral group-cholesterol as the hydrophobic part is a quite effective strategy to get phosphocholine-based LMWG, in which strong hydrogen bonds cannot be directly formed. A series of phospholipid hydrogelators, in which hydrophilic phosphocholine was connected to the chiral hydrophobic cholesteryl group through an alkyl chain, were designed and synthesized. Cholesteryl group greatly promoted the formation of one-dimensional supramolecular structures: helical nanofibril, twisted nanoribbon, helical nanotube, and spindle shaped vesicles were formed, and they showed drastic variation with just simple minor change on the molecular structures. All of them can further organize into cross-linked three-dimensional-networks and form hydrogels. The hydrophobic interaction between cholesteryl groups also greatly improved the performance of hydrogel.