氢键结合超分子水凝胶的形成与结构调控

近年来,依靠单体单元间可逆和高度取向的非共价作用力形成超分子聚合物(supramolecularpolymer)得到广泛关注1,2].在溶液中,超分子单体单元之间通过非共价键相互作用,形成三维网络结构并将有机溶剂或水包裹形成超分子凝胶3,4].相对于聚合物凝胶,超分子凝胶具有以下优点.(1)生

FORMATION AND STRUCTURAL REGULATION OF HYDROGEN-BONDED SUPRAMOLECULAR HYDROGELS

A kind of supramolecular building unit,2,6-diN-(carboxyethyl carbonyl)amino] pyridine(defined as DAP) was synthesized from 2,6-diaminopyridine and succinic anhydride by a simple procedure.The structure of DAP was confirmed by()~1H-NMR,IR and elemental analysis.Supramolecular hydrogels were formed during the cooling of DAP aqueous solutions at a concentration range of 3 wt%～10 wt%.As observed by scanning electron microscopy,supramolecular fibers were noticed in the hydrogels and their dimensions can be regulated by the concentration of DAP.At higher concentrations of DAP,larger fibers and lower hydrogel strengths were resulted.Based on the formation of hydrogen bonds of the molecules an assembling process for supramolecular hydrogels was proposed.