New bisamides gelators:: relationship between chemical structure and fiber morphology

Different dialkoxybenzoic acid derivatives with identical alkyl chain lengths were synthesized and their properties as organogelators evaluated. Only the compounds bearing amide groups behave like gelators. Their gelation abilities and phase diagrams were described. A structural study was conducted by freeze-fracture electron microscopy and showed that the methyl ester formed platelet-like aggregates whereas the corresponding free acid formed thin fibers in the gel. (C) 2003 Elsevier Science Ltd. All rights reserved.