Structural variations in a family of orthodialkoxyarenes organogelators
Pierre Terech1, Gilles Clavier, Henri Bouas-Laurent
1UMR 5819 CEA-CNRS-Univ. J. Fourier, DRFMC-SI3M, CEA-Grenoble 17, rue des Martyrs, 38054 Grenoble Cedex 9, France. pierre.terech@cea.fr
Abstract:
A series of low mass organic gelators (LMOGS) 1 to 6 whose chemical structures have in common an orthodialkoxyarene feature was prepared in order to compare the shape of their fibrillar network as investigated by small-angle neutron scattering (SANS) experiments. All members of the family exhibit a pronounced tendency to bundle formation by merging isolated fibers in extended packets of average diameter >500 A. Variations of the 2D packing symmetry are observed from hexagonal to square orderings with close derivatives of the reference member 2,3-didecyloxyanthracene (DDOA). Networks in which the fraction of isolated fibers is significant enough to allow for their SANS identification are those for 6,7-dichloro-2,3-didecyloxyanthracene (Cl(2)DDOA) and 2,3-dodecyloxy-9,10-anthraquinone (5). For this latter, the monodispersity of the cross-sections (thickness=74 A) is remarkable and the rectangular shape (b/a approximately 0.12) accounts for a merging mechanism into anisotropic bundles (ribbons).
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