A synchrotron small-angle X-ray scattering study on structures of 1,3:2,4-dibenzylidene sorbitol gels

作者：Takeno Hiroyuki^*; Kuribayashi Yuta

来源：Colloids and Surfaces A: Physicochemical and Engineering Aspects , 2015, 467: 173-179.

DOI：10.1016/j.colsurfa.2014.11.051

Small-angle X-ray scattering Lowmolecular weight organogelator structures of 1,3: 2,4- dibenzylidene sorbitol (DBS) gels in various solvents at temperatures above andbelow the sol- gel transition temperatures. DBS formed a transparent gel in acetophenone, while it formeda turbid gel in ionic liquids such as 1- butyl- 3- methyl- imidazolium bis(trifluoromethylsulfonyl)- imide[BMIm][TFSI] and 1- ethyl- 3- methylimidazolium bis(trifluoromethanesulfonyl) imide [EMIm][TFSI]. Synchrotron SAXS analysis reveals that the transparent gel in acetophenone forms fibrillar aggregatescomposed of circular cross- section with a radius ranging from 34 to 43 angstrom depending upon temperature, while the turbid gels in the ionic liquids form thicker nanofibrils in comparison with the transparent gel. As temperature approached the sol- gel transition temperature, the fibrillar aggregates in both gels gradually melted. As a consequence, the cross- sectional size of the fibrillar aggregates for the transparent gelbecame more homogeneous due to melting of thermodynamically unstable thinner fibrils, while the spatial inhomogeneities of the aggregates for the turbid gel became remarkable near the sol- gel transitiontemperature. c 2014 Elsevier B. V.

• 出版日期2015-2-20